Role of sulfates on highway heave in Lake County, Ohio.

DOT National Transportation Integrated Search

2014-01-01

Samples from borings in areas of heave on Route 2, Lake County, OH were analyzed for the amount, mineral form, : and distribution of sulfates. In addition, samples of non-stabilized (NSS) and cement-stabilized (CSS) soils from : three stations along ...

Petrologic comparisons of Cayley and Descartes on the basis of Apollo 16 soils from stations 4 and 11

NASA Technical Reports Server (NTRS)

Basu, A.; Mckay, D. S.

1984-01-01

Petrologic aspects of the Cayley and Descartes formations are reviewed in the light of new data on Apollo 16 soils. Specific comparison of the modal abundances of lithic fragments in drive tube sample 64001/2 from the slopes of Stone Mountain (station 4) and in soil 67941 from the North Ray Crater rim (station 11) shows that melt rocks, especially poikilitic rocks, are more abundant at station 4 than at station 11; the reverse is true for fragmental breccias. Such lithologic differences suggest that stations 4 and 11 do not belong to the same geologic formation. Metamorphosed breccias are pervasive in both the formations and may represent a local component that has been reworked and diluted as fresh materials were added. Lithologic compositions inferred from the study of soil samples are different from lithologic compositions inferred from the study of rake samples or breccia clasts. This difference may be related to a mixing of material of different grain size distributions. The petrology of soils at the Apollo 16 site may not accurately reflect original material associated with either the Descartes or the Cayley formation because of extensive mixing with local material.

Estimating distribution parameters of annual maximum streamflows in Johor, Malaysia using TL-moments approach

NASA Astrophysics Data System (ADS)

Mat Jan, Nur Amalina; Shabri, Ani

2017-01-01

TL-moments approach has been used in an analysis to identify the best-fitting distributions to represent the annual series of maximum streamflow data over seven stations in Johor, Malaysia. The TL-moments with different trimming values are used to estimate the parameter of the selected distributions namely: Three-parameter lognormal (LN3) and Pearson Type III (P3) distribution. The main objective of this study is to derive the TL-moments ( t 1,0), t 1 = 1,2,3,4 methods for LN3 and P3 distributions. The performance of TL-moments ( t 1,0), t 1 = 1,2,3,4 was compared with L-moments through Monte Carlo simulation and streamflow data over a station in Johor, Malaysia. The absolute error is used to test the influence of TL-moments methods on estimated probability distribution functions. From the cases in this study, the results show that TL-moments with four trimmed smallest values from the conceptual sample (TL-moments [4, 0]) of LN3 distribution was the most appropriate in most of the stations of the annual maximum streamflow series in Johor, Malaysia.

The influence of sawmill wood wastes on the distribution and population of macroinvertebrates at Benin River, Niger Delta area, Nigeria.

PubMed

Arimoro, Francis O; Osakwe, Emeka I

2006-05-01

The impact of sawmill wood wastes on the distribution of benthic macroinvertebrates at the Sapele section of Benin River, Niger Delta, Nigeria, was investigated from March 2005 to August 2005. A total of 434 individuals were collected by kick-sampling method, representing 21 taxa of benthic macroinvertebrates. Three stations, 1, 2, and 3, were selected from upstream of the site, receiving wood wastes discharge, the impacted site and its down stream, respectively. Among the water quality variables, conductivity, dissolved oxygen, biochemical oxigen demand (BOD(5)), nitrate-nitrogen, phosphate-phosphorus, transparency, and alkalinity were significantly different (P<0.05) among the stations. Orthogonal comparison by Duncan's multiple range test showed that station 2 (the impacted site) was the cause of the difference. More sensitive species such as Ephemeroptera or Plecoptera were completely absent from station 2, the impacted site. Species abundance was similar in station 1 and 3, indicating that the wood wastes must have adversely affected the distribution of these macroinvertebrates, especially the intolerant species. The wood waste discharge not only altered the water chemistry, but also stimulated the abundance of less-sensitive macroinvertebrate species.

Relative abundance and distribution of fishes within an established Area of Critical Environmental Concern, of the Amargosa River Canyon and Willow Creek, Inyo and San Bernardino Counties, California

USGS Publications Warehouse

Scoppettone, G. Gary; Hereford, Mark E.; Rissler, Peter H.; Johnson, Danielle M.; Salgado, Antonio

2011-01-01

The Amargosa River Canyon of San Bernardino and Inyo County, California, has been designated by the Bureau of Land Management as an Area of Critical Environmental Concern, due in part to its unique flora and fauna. As a task of the Area of Critical Environmental Concern implementation plan, a survey of native fishes was conducted from June 21 to August 12, 2010. Geographic Information System tools were used to map sampling locations, which were spaced at 50-meter intervals. Global Positioning Systems were used to locate sampling stations, and stations with adequate water for successful trapping were sampled with baited minnow traps. Amargosa River pupfish (Cyprinodon nevadensis amargosae) and speckled dace (Rhinichthys osculus spp.) were widespread throughout Armargosa River Canyon. Throughout the study area 8,558 pupfish were captured at 194 stations; 3,472 speckled dace were captured at 210 stations; 238 red-swamp crayfish (Procambarus clarkia) were captured at 83 stations; and 1,095 western mosquitofish (Gambusia affinus) were captured at 110 stations. Pupfish were most abundant in open water habitat with native riparian vegetation, and they were significantly less abundant where the stream was completely covered by cattails or where saltcedar (Tamarix sp.) dominated the riparian corridor. There was no relationship between stream cover and speckled dace distribution. Non-native western mosquitofish and red-swamp crayfish densities were significantly higher in stream reaches dominated by saltcedar. The continued spread of saltcedar threatens to negatively affect pupfish and potentially reduce speckled dace abundance throughout the Amargosa River Canyon. This study can serve as baseline information for observing native fish populations in the future, as related to potential changes to the Amargosa River Canyon ecosystem.

Integrating scales of seagrass monitoring to meet conservation needs

USGS Publications Warehouse

Neckles, Hilary A.; Kopp, Blaine S.; Peterson, Bradley J.; Pooler, Penelope S.

2012-01-01

We evaluated a hierarchical framework for seagrass monitoring in two estuaries in the northeastern USA: Little Pleasant Bay, Massachusetts, and Great South Bay/Moriches Bay, New York. This approach includes three tiers of monitoring that are integrated across spatial scales and sampling intensities. We identified monitoring attributes for determining attainment of conservation objectives to protect seagrass ecosystems from estuarine nutrient enrichment. Existing mapping programs provided large-scale information on seagrass distribution and bed sizes (tier 1 monitoring). We supplemented this with bay-wide, quadrat-based assessments of seagrass percent cover and canopy height at permanent sampling stations following a spatially distributed random design (tier 2 monitoring). Resampling simulations showed that four observations per station were sufficient to minimize bias in estimating mean percent cover on a bay-wide scale, and sample sizes of 55 stations in a 624-ha system and 198 stations in a 9,220-ha system were sufficient to detect absolute temporal increases in seagrass abundance from 25% to 49% cover and from 4% to 12% cover, respectively. We made high-resolution measurements of seagrass condition (percent cover, canopy height, total and reproductive shoot density, biomass, and seagrass depth limit) at a representative index site in each system (tier 3 monitoring). Tier 3 data helped explain system-wide changes. Our results suggest tiered monitoring as an efficient and feasible way to detect and predict changes in seagrass systems relative to multi-scale conservation objectives.

Electronic resistance tomography imaging of spatial moisture distribution, moisture distribution and movement in pavements

DOT National Transportation Integrated Search

1997-07-01

Electronic resistance tomography (ERT) was used to follow the infiltration of water into a pavement section at the UC Berkeley Richmond Field Station. A volume of pavement 1 m square and 1.29 m in depth was sampled by an ERT array consisting of elect...

Microzooplankton biomass distribution in Terra Nova Bay, Ross Sea (Antarctica)

NASA Astrophysics Data System (ADS)

Fonda Umani, S.; Monti, M.; Nuccio, C.

1998-11-01

This work describes the spatial and vertical distribution of microzooplankton (20-200 μm) abundance and biomass of the upper layers (0-100 m), collected during the first oceanographic Italian expedition in Antarctica (1987/1988) in Terra Nova Bay (Ross Sea). Biomass was estimated by using biovolume calculations and literature conversion factors. Sampling was carried out at three depths, surface, 50 and 100 m. The dominant taxa were made up of tintinnid ciliates, ciliates other than tintinnids, larvae of micrometazoa and heterotrophic dinoflagellates. The abundance of the total microplankton fraction had its absolute maximum in the center of Terra Nova Bay at the surface with 31 042 ind. dm -3. The areal and vertical distribution of heterotrophic microplankton biomass differs from that of abundance. On the basis of hydrological conditions, phytoplankton composition and biomass and microzooplankton biomass and structure it is possible to identify three groups of stations: 1—northern coastal stations (intermediate chlorophyll maxima, microphytoplankton prevalence, low microzooplankton biomass); 2—central stations (high surface chlorophyll, nanoplankton prevalence, high abundance of microzooplankton); 3—northern stations (deeper pycnocline, nanoplankton prevalence, high microzooplankton biomass at intermediate depths).

Omega flight-test data reduction sequence. [computer programs for reduction of navigation data

NASA Technical Reports Server (NTRS)

Lilley, R. W.

1974-01-01

Computer programs for Omega data conversion, summary, and preparation for distribution are presented. Program logic and sample data formats are included, along with operational instructions for each program. Flight data (or data collected in flight format in the laboratory) is provided by the Ohio University Omega receiver base in the form of 6-bit binary words representing the phase of an Omega station with respect to the receiver's local clock. All eight Omega stations are measured in each 10-second Omega time frame. In addition, an event-marker bit and a time-slot D synchronizing bit are recorded. Program FDCON is used to remove data from the flight recorder tape and place it on data-processing cards for later use. Program FDSUM provides for computer plotting of selected LOP's, for single-station phase plots, and for printout of basic signal statistics for each Omega channel. Mean phase and standard deviation are printed, along with data from which a phase distribution can be plotted for each Omega station. Program DACOP simply copies the Omega data deck a controlled number of times, for distribution to users.

Spatial variability of dissolved phosphorous concentrations and alkaline phosphatase activity in the East China Sea

NASA Astrophysics Data System (ADS)

Liu, H.; Chang, J.; Ho, T.; Gong, G.

2010-12-01

The concentrations of dissolved inorganic phosphorus (DIP) and alkaline phosphatase activity (APA) have been determined at about 25 sampling stations in the East China Sea since 2003. The stations are mainly distributed from the Changjiang river mouth to northern Taiwan and east to the shelf break. In addition to the Changjiang discharge, we have found a specific nutrient source around a coastal site (122° 2’30’’ E, 28° 40’ N). Elevated DIP and nitrate concentrations have been constantly observed around the sampling station for 8 years, where the surface DIP concentrations are generally around 0.3 µM. The nutrient source may either originate from ground water discharge or coastal upwelling, where lower temperature has been observed in the water column around the station. In general, APA has been negatively correlated with DIP concentrations in the studies sites, with lowest APA around the high DIP station and the Changjiang river mouth.

Nitrate and Phosphate Contents on Sediments Related to The Density Levels of Mangrove Rhizophora Sp. in Mangrove Park Waters of Pekalongan, Central Java

NASA Astrophysics Data System (ADS)

Supriyantini, E.; Santoso, A.; Soenardjo, N.

2018-02-01

Mangrove Park waters area of Pekalongan City, Central Java, used to be an aquaculture field, now turning the function into a restoration-based mangrove area, and now it has undergone rehabilitation. The conditions may affect the distribution of nitrate and phosphate content. The objective of this study was to determine the content of nitrates and phosphates in sediments related to the density levels of mangrove Rhizophora sp. The method used in this research was a descriptive method, and sampling was done by purposive sampling method. Water and sediment sampling were conducted at three stations respectively, representing: no mangrove area but used as a residential and tourist area (station 1); less dense mangrove (station 2); and, the previously aquaculture field - or medium dense mangrove (station 3). The results showed that the content of nitrate and phosphate in the whole sediment showed a low fertility rate. Average nitrate content for station 1, station 2 and station 3 were 0.86 mg/100 g, 0.94 mg/100 g and 0.81 mg/100 g, respectively. The average phosphate content at each station were 1.14 mg/100 g, 0.04 mg/100 g and 0.05 mg/100 g, respectively. Except to the station 1 that was no vegetation anymore, the mangrove density levels at two other stations at study sites were relatively low to medium; at station 2 was 0.8 ind/10 m2 and at station 3 was 1.2 ind/10 m2. The role of nitrate and phosphate were for mangrove growth at the site.

First evaluation of neustonic microplastics in Black Sea waters.

PubMed

Aytan, Ulgen; Valente, Andre; Senturk, Yasemen; Usta, Riza; Esensoy Sahin, Fatma Basak; Mazlum, Rahsan Evren; Agirbas, Ertugrul

2016-08-01

The Black Sea has a high risk of plastic pollution given the high river discharge of several industrialized countries into this semi-enclosed sea. Here, for the first time, the occurrence and distribution of microplastics are reported for the Black Sea. Microplastics were assessed from zooplankton samples taken during two cruises along the south eastern coast of the Black Sea in the November of 2014 and February of 2015. In each cruise neuston samples were collected at 12 stations using a WP2 net with 200 μm mesh. Microplastics (0.2-5 mm) were found in 92% of the samples. The primary shapes were fibres (49.4%) followed by plastic films (30.6%) and fragments (20%), and no micro beads were found. Average microplastic concentration in November (1.2 ± 1.1 × 10(3) par. m(-3)) was higher than in February (0.6 ± 0.55 × 10(3) par. m(-3)). Reduced concentrations in February were possibly caused by increased mixing. The highest concentrations of microplastics were observed in offshore stations during November sampling. The heterogeneous spatial distribution (0.2 × 10(3)-3.3 × 10(3) par. m(-3) for all samples) and accumulation in some stations could be associated to transport and retention mechanisms linked with wind and the dynamics of the rim current, as well by different sources of plastic. There were no statistically significant differences in MP concentration between sampling stations and sampling periods (t-test, p < 0.05).The relatively high microplastic concentrations suggest that Black Sea is a hotspot for microplastic pollution and there is an urgency to understand their origins, transportation and effects on marine life. Copyright © 2016 Elsevier Ltd. All rights reserved.

Meso-zooplankton abundance and spatial distribution off Lützow-Holm Bay during austral summer 2007-2008

NASA Astrophysics Data System (ADS)

Makabe, Ryosuke; Tanimura, Atsushi; Tamura, Takeshi; Hirano, Daisuke; Shimada, Keishi; Hashihama, Fuminori; Fukuchi, Mitsuo

2017-06-01

To elucidate spatial differences in mesozooplankton community structure in local scale, vertical hauls using a 60-μm mesh closing net were carried out off Lützow-Holm Bay in January 2008. All of the zooplankton samples collected from three layers (0-100, 100-200, and 200-500 m) at seven stations were dominated by Oithona spp., Oncaea spp., Ctenocalanus citer, Microcalanus pygmaeus, and copepod nauplii. The cluster analysis of mesozooplankton abundances showed three distinct groups according to sampling depth, which appeared to be due to the preferential vertical distribution of dominant copepods. The other cluster analysis on integrated abundance upper 500 m revealed that mesozooplankton community structures at stations located on the western and eastern edges of the observation area (Cluster A) differed from those at the central stations (Cluster B). Abundance of copepod nauplii, Oithona spp., and C. citer differed between Clusters A and B, which was likely caused by differences in recruitment and early development in the dominant copepods, being associated with the timing and duration of ice edge blooms. This suggests that such heterogeneity in abundance and recruitment/development of dominant taxa was likely caused by local heterogeneity in sea ice dynamics. This may affect our understanding of zooplankton distribution.

Abundance and Distribution Characteristics of Microplastics in Surface Seawaters of the Incheon/Kyeonggi Coastal Region.

PubMed

Chae, Doo-Hyeon; Kim, In-Sung; Kim, Seung-Kyu; Song, Young Kyoung; Shim, Won Joon

2015-10-01

Microplastics in marine environments are of emerging concern due to their widespread distribution, their ingestion by various marine organisms, and their roles as a source and transfer vector of toxic chemicals. However, our understanding of their abundance and distribution characteristics in surface seawater (SSW) remains limited. We investigated microplastics in the surface microlayer (SML) and the SSW at 12 stations near-shore and offshore of the Korean west coast, Incheon/Kyeonggi region. Variation between stations, sampling media, and sampling methods were compared based on abundances, size distribution, and composition profiles of microsized synthetic polymer particles. The abundance of microplastics was greater in the SML (152,688 ± 92,384 particles/m(3)) than in SSW and showed a significant difference based on the sampling method for SSWs collected using a hand net (1602 ± 1274 particles/m(3)) and a zooplankton trawl net (0.19 ± 0.14 particles/m(3)). Ship paint particles (mostly alkyd resin polymer) accounted for the majority of microplastics detected in both SML and SSWs, and increased levels were observed around the voyage routes of large vessels. This indicates that polymers with marine-based origins become an important contributor to microplastics in coastal SSWs of this coastal region.

Temporal distribution of intertidal macrozoobenthic assemblages in a Nanozostera noltii-dominated area (Lagoon of Venice).

PubMed

Tagliapietra, D; Pessa, G; Cornello, M; Zitelli, A; Magni, P

2016-03-01

We describe the temporal distribution of intertidal macrozoobenthic assemblages in a small marsh pond of the Lagoon of Venice colonized by the seagrass Nanozostera noltii (Hornemman) Tomlinson et Posluzny. Three stations ranging in the degree of N. noltii cover were selected about 100 m apart and sampled 9 times at regular intervals from March 1996 to March 1997. We applied the concepts of resistance and resilience to "natural stress" (e.g. extent of protection from seagrass meadows, exposure of macrozoobenthic assemblages to high temperatures in summer) with the aim to assess the stability of a community along a gradient of seagrass coverage. Results showed that the most structured and taxa-rich macrozoobenthic assemblage occurred at the station covered by a continuous stand of N. noltii, where permanent taxa (i.e. found in 100% of samples) were almost double than those found at the other stations. During the annual cycle, the macrozoobenthic assemblages showed a cyclical pattern, with temporal fluctuations increasing as they moved further away from the seagrass beds. We propose the role of N. noltii offering structural complexity and stability as the more probable explanation to the observed differences between stations in the intertidal assemblages. Copyright © 2015 Elsevier Ltd. All rights reserved.

Global tropospheric experiment at the Hong Kong Atmosphere Chemistry Measurement Station

NASA Technical Reports Server (NTRS)

Carroll, Mary Ann; Wang, Tao

1995-01-01

The major activities of the Global Tropospheric Experiment at the Hong Kong Atmospheric Chemistry Measurement Station are presented for the period 1 January - 31 December 1995. Activities included data analysis, reduction, and archiving of atmospheric measurements and sampling. Sampling included O3, CO, SO2, NO, TSP, RSP, and ozone column density. A data archive was created for the surface meteorological data. Exploratory data analysis was performed, including examination of time series, frequency distributions, diurnal variations and correlation. The major results have been or will be published in scientific journals as well as presented at conferences/workshops. Abstracts are attached.

[Exploring nurse, usage effectiveness of mobile nursing station].

PubMed

Chang, Fang-Mei; Lee, Ting-Ting

2013-04-01

A mobile nursing station is an innovative cart that integrates a wireless network, information technology devices, and online charts. In addition to improving clinical work and workflow efficiencies, data is integrated among different information systems and hardware devices to promote patient safety. This study investigated the effectiveness of mobile nursing cart use. We compared different distributions of nursing activity working samples to evaluate the nursing information systems in terms of interface usability and usage outcomes. There were two parts of this study. Part one used work sampling to collect nursing activity data necessary to compare a unit that used a mobile nursing cart (mobile group, n = 18) with another that did not (traditional group, n = 14). Part two applied a nursing information system interface usability questionnaire to survey the mobile unit with nurses who had used a mobile nursing station (including those who had worked in this unit as floating nurses) (n = 30) in order to explore interface usability and effectiveness. We found that using the mobile nursing station information system increased time spent on direct patient care and decreased time spent on indirect patient care and documentation. Results further indicated that participants rated interface usability as high and evaluated usage effectiveness positively. Comments made in the open-ended question section raised several points of concern, including problems / inadequacies related to hardware devices, Internet speed, and printing. This study indicates that using mobile nursing station can improve nursing activity distributions and that nurses hold generally positive attitudes toward mobile nursing station interface usability and usage effectiveness. The authors thus encourage the continued implementation of mobile nursing stations and related studies to further enhance clinical nursing care.

Lithologic distribution and geologic history of the Apollo 17 site: The record in soils and small rock particles from the highland massifs

NASA Astrophysics Data System (ADS)

Jolliff, Bradley L.; Rockow, Kaylynn M.; Korotev, Randy L.; Haskin, Larry A.

1996-01-01

Through analysis by instrumental neutron activation (INAA) of 789 individual lithic fragments from the 2 mm-4 mm grain-size fractions of five Apollo 17 soil samples (72443, 72503, 73243, 76283, and 76503) and petrographic examination of a subset, we have determined the diversity and proportions of rock types recorded within soils from the highland massifs. The distribution of rock types at the site, as recorded by lithic fragments in the soils, is an alternative to the distribution inferred from the limited number of large rock samples. The compositions and proportions of 2 mm-4 mm fragments provide a bridge between compositions of <1 mm fines, and types and proportions of rocks observed in large collected breccias and their clasts. The 2 mm-4 mm fraction of soil from South Massif, represented by an unbiased set of lithic fragments from station-2 samples 72443 and 72503, consists of 71% noritic impact-melt breccia, 7% incompatible-trace-element-(ITE)-poor highland rock types (mainly granulitic breccias), 19% agglutinates and regolith breccias, 1% high-Ti mare basalt, and 2% others (very-low-Ti (VLT) basalt, monzogabbro breccia, and metal). In contrast, the 2 mm-4 mm fraction of a soil from the North Massif, represented by an unbiased set of lithic fragments from station-6 sample 76503, has a greater proportion of ITE-poor highland rock types and mare-basalt fragments: it consists of 29% ITE-poor highland rock types (mainly granulitic breccias and troctolitic anorthosite), 25% impact-melt breccia, 13% high-Ti mare basalt, 31% agglutinates and regolith breccias, 1% orange glass and related breccia, and 1% others. Based on a comparison of mass-weighted mean compositions of the lithic fragments with compositions of soil fines from all Apollo 17 highland stations, differences between the station-2 and station-6 samples are representative of differences between available samples from the two massifs. From the distribution of different rock types and their compositions, we conclude the following: (1) North-Massif and South-Massif soil samples differ significantly in types and proportions of ITE-poor highland components and ITE-rich impact-melt-breccia components. These differences reflect crudely layered massifs and known local geology. The greater percentage of impact-melt breccia in the South-Massif light-mantle soil stems from derivation of the light mantle from the top of the massif, which apparently is richer in noritic impact-melt breccia than are lower parts of the massifs. (2) At station 2, the 2 mm-4 mm grain-size fraction is enriched in impact-melt breccias compared to the <1 mm fraction, suggesting that the <1 mm fraction within the light mantle has a greater proportion of lithologies such as granulitic breccias which are more prevalent lower in the massifs and which we infer to be older (pre-basin) highland components. (3) Soil from station 6, North Massif, contains magnesian troctolitic anorthosite, which is a component that is rare in station-2 South-Massif soils. (4) Compositional differences between poikilitic impact-melt breccias from the two massifs suggest broad-scale heterogeneity in impact-melt breccia interpreted by most investigators to be ejecta from the Serenitatis basin. We have found rock types not previously recognized or uncommon at the Apollo 17 site. These include (1) ITE-rich impact-melt breccias that are compositionally distinct from previously recognized "aphanitic" and "poikilitic" groups at Apollo 17; (2) regolith breccias that are free of mare components and poor in impact melt of the types associated with the main melt-breccia groups, and that, if those groups derive from the Serenitatis impact, may represent the pre-Serenitatis surface; (3) several VLT basalts, including an unusual very-high-K basaltic breccia; (4) orange-glass regolith breccias; (5) aphanitic-matrix melt breccias at station 6; (6) fragments of alkali-rich composition, including alkali anorthosite, and monzogabbro; (7) one fragment of 72275-type KREEP basalt from station 3; (8) seven lithic fragments of ferroan-anorthositic-suite rocks; and (9) a fragment of metal, possibly from an L chondrite. Some of these lithologies have been found only as lithic fragments in the soils and not among the large rock samples. In contrast, we have not found among the 2 mm-4 mm lithic fragments individual samples of certain lithologies that have been recognized as clasts in breccias (e.g., dunite and spinel troctolite). The diversity of lithologic information contained in the lithic fragments of these soils nearly equals that found among large rock samples, and most information bearing on petrographic relationships is maintained, even in such small samples. Given a small number of large samples for "petrologic ground truth," small lithic fragments contained in soil "scoop" samples can provide the basis for interpreting the diversity of rock types and their proportions in remotely sensed geologic units. They should be considered essential targets for future automated sample-analysis and sample-return missions.

Characterization of the Distribution of Siderophile and Highly Siderophile Elements in the Milton and Eagle Station Pallasites

NASA Technical Reports Server (NTRS)

Hillebrand, J. T.; McDonough, W. F.; Walker, R. J.; Piccoli, P. M.

2004-01-01

We examine the partitioning characteristics of several siderophile elements and HSE in the Eagle Station and Milton pallasites to determine if the D(sup Metal/Silicate) in natural systems are comparable to the range of values determined for synthetic systems. Eagle Station and Milton are particularly appropriate for this type of study because previous studies have shown that bulk samples of these meteorites have much higher abundances of siderophile elements and HSE than bulk samples of main group pallasites or mesosiderites. Thus, the expectation that initiated this study was that the abundances of at least some elements of interest present in the silicate phases may be at levels sufficiently high to be determined via in situ spot analysis using laser ablation ICP-MS.

Assessment of trace element contamination of urban surface soil at informal industrial sites in a low-income country.

PubMed

Kanda, Artwell; Ncube, France; Hwende, Tamuka; Makumbe, Peter

2018-05-29

Trace elements released by human activity are ubiquitously detected in surface soil. The trace element contamination statuses of 20 sampling stations at two busy informal industrial sites of Harare city, Zimbabwe, were evaluated using geochemical indices. Spectrophotometric determinations of concentrations of trace elements in surface soil indicated generally higher values than the reference site and the average upper earth's crust. High contamination factors were observed for trace elements across sampling stations at Gazaland and Siyaso informal industrial sites. Concentrations exhibited heterogeneous distribution of trace elements in surface soil varying with the nature of activity at a sampling station. The pollution load index and degree of contamination suggested highly contaminated surface soil with Cd, Cu and Pb particularly where the following activities were done: (1) welding, (2) automobile maintenance and (3) waste dumping. These results may be very important to reduce soil contamination. Paving surfaces may help to reduce dispersal of trace elements deposited on surface soil to other stations and minimise human exposure via inhalation and contact.

Results of Macroinvertebrate Sampling Conducted at 33 SRS Stream Locations, July--August 1993

DOE Office of Scientific and Technical Information (OSTI.GOV)

Specht, W.L.

1994-12-01

In order to assess the health of the macroinvertebrate communities of SRS streams, the macroinvertebrate communities at 30 stream locations on SRS were sampled during the summer of 1993, using Hester-Dendy multiplate samplers. In addition, three off-site locations in the Upper Three Runs drainage were sampled in order to assess the potential for impact from off-site activities. In interpreting the data, it is important to recognize that these data were from a single set of collections. Macroinvertebrate communities often undergo considerable temporal variation, and are also greatly influenced by such factors as water depth, water velocity, and available habitat. Thesemore » stations were selected with the intent of developing an on-going sampling program at a smaller number of stations, with the selection of the stations to be based largely upon the results of this preliminary sampling program. When stations within a given stream showed similar results, fewer stations would be sampled in the future. Similarly, if a stream appeared to be perturbed, additional stations or chemical analyses might be added so that the source of the perturbation could be identified. In general, unperturbed streams will contain more taxa than perturbed streams, and the distribution of taxa among orders or families will differ. Some groups of macroinvertebrates, such as Ephemeroptera (mayflies), Plecoptera (stoneflies) and Trichoptera (caddisflies), which are collectively called EPT taxa, are considered to be relatively sensitive to most kinds of stream perturbation; therefore a reduced number of EPT taxa generally indicates that the stream has been subject to chemical or physical stressors. In coastal plain streams, EPT taxa are generally less dominant than in streams with rocky substrates, while Chironomidae (midges) are more abundant. (Abstract Truncated)« less

Coliphage and indigenous phage in Mamala Bay, Oahu, Hawaii.

PubMed

Paul, J H; Rose, J B; Jiang, S C; London, P; Xhou, X; Kellogg, C

1997-01-01

Public concern over the discharge of primarily treated sewage by two offshore outfalls in Mamala Bay, Oahu, prompted a multidisciplinary study to determine the impact of such activities on the water quality in the bay and at adjacent recreational beaches. As part of this study, we determined the abundance of coliphage as an indicator of fecal pollution along with total viral direct counts and phages infective for Vibrio parahaemoltyicus 16 at stations in Mamala Bay in four quarterly samplings over 13 months. Coliphage (< 1 to 1.2 x 10(3)/liter) were found during each quarterly sampling along an offshore transect to the Sand Island waste treatment facility outfall. The nonpoint coastal stations (Pearl Harbor, Ala Wai Canal, and Ke'ehi Lagoon) had high levels of coliphage during the storm event sampling in February 1994 but much lower levels or none when sampled during dry weather. Coliphage were absent at all samplings at Waikiki Beach and at the control station off Diamond Head. Viral direct counts in eutrophic coastal stations (Pearl Harbor, Ke'ehi Lagoon, Ala Moana Beach, and Ala Wai canal) averaged 10(9)/liter, while counts at offshore stations ranged from 9 x 10(7) to 1 x 10(9) viruses/liter, values similar to those for other marine environments. Vibriophage were found mainly in eutrophic coastal environments (Ala Wai Canal, Pearl Harbor, and Ke'ehi Lagoon) and at the Sand Island Transect stations D1 and D2. The greatest abundance was found during the storm event (February 1994) sampling. These results suggest that the Sand Island outfall influenced the water quality of the immediate surrounding waters but had little effect on the quality of the recreational beaches. Nonpoint discharge sources appeared to be more important in the distribution of fecal indicators in the coastal zone.

The ExoMars Sample Preparation and Distribution System

NASA Astrophysics Data System (ADS)

Schulte, Wolfgang; Hofmann, Peter; Baglioni, Pietro; Richter, Lutz; Redlich, . Daniel; Notarnicola, Marco; Durrant, Stephen

2012-07-01

The Sample Preparation and Distribution System (SPDS) is a key element of the ESA ExoMars Rover. It is a set of complex mechanisms designed to receive Mars soil samples acquired from the subsurface with a drill, to crush them and to distribute the obtained soil powder to the scientific instruments of the `Pasteur Payload', in the Rover Analytical Laboratory (ALD). In particular, the SPDS consists of: (1) a Core Sample Handling System (CSHS), including a Core Sample Transportation Mechanism (CSTM) and a Blank Sample Dispenser; (2) a Crushing Station (CS); (3) a Powder Sample Dosing and Distribution System (PSDDS); and (4) a Powder Sample Handling System (PSHS) which is a carousel carrying pyrolysis ovens, a re-fillable sample container and a tool to flatten the powder sample surface. Kayser-Threde has developed, undercontract with the ExoMars prime contractor Thales Alenia Space Italy, breadboards and an engineering model of the SPDS mechanisms. Tests of individual mechanisms, namely the CSTM, CS and PSDDS were conducted both in laboratory ambient conditions and in a simulated Mars environment, using dedicated facilities. The SPDS functionalities and performances were measured and evaluated. In the course of 2011 the SPDS Dosing Station (part of the PSDDS) was also tested in simulated Mars gravity conditions during a parabolic flight campaign. By the time of the conference, an elegant breadboard of the Powder Sample Handling System will have been built and tested. The next step, planned by mid of 2012, will be a complete end-to-end test of the sample handling and processing chain, combining all four SPDS mechanisms. The possibility to verify interface and operational aspects between the SPDS and the ALD scientific instruments using the available instruments breadboards with the end-to-end set-up is currently being evaluated. This paper illustrates the most recent design status of the SPDS mechanisms, summarizes the test results and highlights future development activities, including potential involvement of the ExoMars science experiments.

Sub-soil contamination due to oil spills in six oil-pipeline pumping stations in northern Mexico.

PubMed

Iturbe, Rosario; Flores, Carlos; Castro, Alejandrina; Torres, Luis G

2007-06-01

Mexico has a very important oil industry, comprehending the exploration, production, transformation, storage and distribution of crude oil and its fractions. Petroleos Mexicanos (PEMEX) is a state-owned monopoly in charge of these activities. Oil and oil-products transport is an extremely crucial operation for the cycle production-transformation-distribution. Pipeline system transport crude oil and sub-products along the country (including liquids, gases and mixtures). It has been reported that more than 30% of the oil ducts in Mexico have been operating for over 30 years, although their lifetime has been calculated in 25-30 years. This work is aimed at characterizing a zone around six oil-pipeline pumping stations located at northern Mexico. The specific places to evaluate soil contamination were (1) the distribution head of the Gomez Palacio (GOPA) pumping station; (2) the north side of the old ditch, the API oil separator and the wastewater zones of the Jimenez (JIM) pumping station; (3) the pumping stations of Ceballos (CE), Peronal (PER), Simon Bolivar (SIBO), and Mayran (MAY). The study comprehended sampling of the areas, delimitation of contamination in the vertical and horizontal extension, analysis of the sampled soils, regarding TPH and, in some cases, the 16 PAHs considered as a priority by USEPA, calculation of areas and volumes contaminated (according to the Mexican legislation, specifically NOM-EM-138-ECOL-2002) and, finally, a proposal for the best remediation techniques suitable for the encountered contamination levels and the localization of contaminants. In general, TPHs were found in all the pumping stations analyzed in this study. Regarding maximal TPHs concentrations at the stations, their order of contamination was as follows: SIBO>CE>PER>MAY>JIM>GOPA. PAHs were found only in a few points at concentrations above the detection limit. At the Jimenez, Gomez Palacio, Peronal, and Ceballos stations, only one point, with PAHs values over the detection limit was found, whereas two points were found at Mayran, and finally at the Simon Bolivar station there were four points with measurable amounts of PAHs. Given the areas and volumes that need to be treated (32835 m3), as well as the physical position of contaminants, it is considered that excavation of the contaminated soil is feasible and the cleaning process could be soil washing assisted with surfactants, though bioremediation should not been discharged as a possible remediation technique.

A climatology of ⁷Be in surface air in European Union.

PubMed

Hernández-Ceballos, M A; Cinelli, G; Ferrer, M Marín; Tollefsen, T; De Felice, L; Nweke, E; Tognoli, P V; Vanzo, S; De Cort, M

2015-03-01

This study presents a European-wide analysis of the spatial and temporal distribution of the cosmogenic isotope (7)Be in surface air. This is the first time that a long term database of 34 sampling sites that regularly provide data to the Radioactivity Environmental Monitoring (REM) network, managed by the Joint Research Centre (JRC) in Ispra, is used. While temporal coverage varies between stations, some of them have delivered data more or less continuously from 1984 to 2011. The station locations were considerably heterogeneous, both in terms of latitude and altitude, a range which should ensure a high degree of representativeness of the results. The mean values of (7)Be activity concentration presented a spatial distribution value ranging from 2.0 to 5.4 mBq/m(3) over the European Union. The results of the ANOVA analysis of all (7)Be data available indicated that its temporal and spatial distributions were mainly explained by the location and characteristic of the sampling sites rather than its temporal distribution (yearly, seasonal and monthly). Higher (7)Be concentrations were registered at the middle, compared to high-latitude, regions. However, there was no correlation with altitude, since all stations are sited within the atmospheric boundary layer. In addition, the total and yearly analyses of the data indicated a dynamic range of (7)Be activity for each solar cycle and phase (maximum or minimum), different impact on stations having been observed according to their location. Finally, the results indicated a significant seasonal and monthly variation for (7)Be activity concentration across the European Union, with maximum concentrations occurring in the summer and minimum in the winter, although with differences in the values reached. The knowledge of the horizontal and vertical distribution of this natural radionuclide in the atmosphere is a key parameter for modelling studies of atmospheric processes, which are important phenomena to be taken into account in the case of a nuclear accident. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.

Nutrients, Select Pesticides, and Suspended Sediment in the Karst Terrane of the Sinking Creek Basin, Kentucky, 2004-06

USGS Publications Warehouse

Crain, Angela S.

2010-01-01

This report presents the results of a study by the U.S. Geological Survey, in cooperation with the Kentucky Department of Agriculture, on nutrients, select pesticides, and suspended sediment in the karst terrane of the Sinking Creek Basin. Streamflow, nutrient, select pesticide, and suspended-sediment data were collected at seven sampling stations from 2004 through 2006. Concentrations of nitrite plus nitrate ranged from 0.21 to 4.9 milligrams per liter (mg/L) at the seven stations. The median concentration of nitrite plus nitrate for all stations sampled was 1.6 mg/L. Total phosphorus concentrations were greater than 0.1 mg/L, the U.S. Environmental Protection Agency's recommended maximum concentration, in 45 percent of the samples. Concentrations of orthophosphates ranged from less than 0.006 to 0.46 mg/L. Concentrations of nutrients generally were larger during spring and summer months, corresponding to periods of increased fertilizer application on agricultural lands. Concentrations of suspended sediment ranged from 1.0 to 1,490 mg/L at the seven stations. Of the 47 pesticides analyzed, 14 were detected above the adjusted method reporting level of 0.01 micrograms per liter (mug/L). Although these pesticides were detected in water-quality samples, they generally were found at less than part-per-billion concentrations. Atrazine was the only pesticide detected at concentrations greater than U.S. Environmental Protection Agency drinking water standard of 3 mug/L, and the maximum detected concentration was 24.6 mug/L. Loads and yields of nutrients, selected pesticides, and suspended sediment were estimated at two mainstream stations on Sinking Creek, a headwater station (Sinking Creek at Rosetta) and a station at the basin outlet (Sinking Creek near Lodiburg). Mean daily streamflow data were available for the estimation of loads and yields from a stream gage at the basin outlet station; however, only periodic instantaneous flow measurements were available for the headwaters station; mean daily flows at the headwater station were, therefore, estimated using a mathematical record-extension technique known as the Maintenance of Variance-Extension, type 1 (MOVE.1). The estimation of mean daily streamflows introduced a large amount of uncertainty into the loads and yields estimates at the headwater station. Total estimated loads of select (five most commonly detected) pesticides from the Sinking Creek Basin were about 0.01 to 1.2 percent of the estimated application, indicating pesticides possibly are retained within the watershed. Mean annual loads [(in/lb)/yr] for nutrients and suspended sediment were estimated at the two Sinking Creek mainstem sampling stations. The relation between estimated and measured instantaneous loads of nitrite plus nitrate at the Sinking Creek near Lodiburg station indicate a reasonably tight distribution over the range of loads. The model for loads of nitrite plus nitrate at the Sinking Creek at Rosetta station indicates small loads were overestimated and underestimated. Relations between estimated and measured loads of total phosphorus and orthophosphate at both Sinking Creek mainstem stations showed similar patterns to the loads of nitrite plus nitrate at each respective station. The estimated mean annual load of suspended sediment is about 14 times larger at the Sinking Creek near Lodiburg station than at the Sinking Creek near Rosetta station. Estimated yields of nutrients and suspended sediment increased from the headwater to downstream monitoring stations on Sinking Creek. This finding suggests that sources of nutrients and suspended sediment are not evenly distributed throughout the karst terrane of the Sinking Creek Basin. Yields of select pesticides generally were similar from the headwater to downstream monitoring stations. However, the estimated yield of atrazine was about five times higher at the downstream station on Sinking Creek than at the headwater station on Sinking Creek.

Relative abundance and distribution of fishes and crayfish at Ash Meadows National Wildlife Refuge, Nye County, Nevada, 2007-08

USGS Publications Warehouse

Scoppettone, G. Gary; Rissler, Peter; Johnson, Danielle; Hereford, Mark

2011-01-01

This study provides baseline data of native and non-native fish populations in Ash Meadows National Wildlife Refuge (NWR), Nye County, Nevada, that can serve as a gauge in native fish enhancement efforts. In support of Carson Slough restoration, comprehensive surveys of Ash Meadows NWR fishes were conducted seasonally from fall 2007 through summer 2008. A total of 853 sampling stations were created using Geographic Information Systems and National Agricultural Imagery Program. In four seasons of sampling, Amargosa pupfish (genus Cyprinodon) was captured at 388 of 659 stations. The number of captured Amargosa pupfish ranged from 5,815 (winter 2008) to 8,346 (summer 2008). The greatest success in capturing Amargosa pupfish was in warm water spring-pools with temperature greater than 25 degrees C, headwaters of warm water spring systems, and shallow (depths less than 10 centimeters) grassy marshes. In four seasons of sampling, Ash Meadows speckled dace (Rhinichthys osculus nevadesis) was captured at 96 of 659 stations. The number of captured Ash Meadows speckled dace ranged from 1,009 (summer 2008) to 1,552 (winter 2008). The greatest success in capturing Ash Meadows speckled dace was in cool water spring-pools with temperature less than 20 degrees C and in the high flowing water outflows. Among 659 sampling stations within the range of Amargosa pupfish, red swamp crayfish (Procambarus clarkii) was collected at 458 stations, western mosquitofish (Gambusia affinis) at 374 stations, and sailfin molly (Poecilia latipinna) at 128 stations. School Springs was restored during the course of this study. Prior to restoration of School Springs, maximum Warm Springs Amargosa pupfish (Cyprinodon nevadensis pectoralis) captured from the six springs of the Warm Springs Complex was 765 (fall 2007). In four seasons of sampling, Warm Springs Amargosa pupfish were captured at 85 of 177 stations. The greatest success in capturing Warm Springs Amargosa pupfish when co-occurring with red swamp crayfish and western mosquitofish was in water with temperature greater than 26 degrees C near the springhead, and in shallow (depths less than 10 centimeters) grassy marshes. Among 177 sampling stations within the range of Warm Springs Amargosa pupfish, red swamp crayfish were collected at 96 stations and western mosquitofish were collected at 49 stations. Removal of convict cichlid (Amatitlania nigrofasciata) from Fairbanks Spring was followed by a substantial increase in Ash Meadows Amargosa pupfish (Cyprinodon nevadensis mionectes) captures from 910 pre-removal to 3,056 post-removal. Red swamp crayfish was continually removed from Bradford 1 Spring, which seemed to cause an increase in the speckled dace population. Restoration of Kings Pool and Jackrabbit Springs promoted the success of native fishes with the greatest densities in restored reaches. Ongoing restoration of Carson Slough and its tributaries, as well as control and elimination of invasive species, is expected to increase abundance and distribution of Ash Meadows' native fish populations. Further analysis of data from this study will help determine the habitat characteristic(s) that promote native species and curtail non-native species.

Effects of sampling techniques on physical parameters and concentrations of selected persistent organic pollutants in suspended matter.

PubMed

Pohlert, Thorsten; Hillebrand, Gudrun; Breitung, Vera

2011-06-01

This study focusses on the effect of sampling techniques for suspended matter in stream water on subsequent particle-size distribution and concentrations of total organic carbon and selected persistent organic pollutants. The key questions are whether differences between the sampling techniques are due to the separation principle of the devices or due to the difference between time-proportional versus integral sampling. Several multivariate homogeneity tests were conducted on an extensive set of field-data that covers the period from 2002 to 2007, when up to three different sampling techniques were deployed in parallel at four monitoring stations of the River Rhine. The results indicate homogeneity for polychlorinated biphenyls, but significant effects due to the sampling techniques on particle-size, organic carbon and hexachlorobenzene. The effects can be amplified depending on the site characteristics of the monitoring stations.

Long-term monitoring of persistent organic pollutants (POPs) at the Norwegian Troll station in Dronning Maud Land, Antarctica

NASA Astrophysics Data System (ADS)

Kallenborn, R.; Breivik, K.; Eckhardt, S.; Lunder, C. R.; Manø, S.; Schlabach, M.; Stohl, A.

2013-03-01

A first long-term monitoring of selected persistent organic pollutants (POPs) in Antarctic air has been conducted at the Norwegian Research station Troll (Dronning Maud Land). As target contaminants 32 PCB congeners, a- and g-hexachlorocyclohexane (HCH), trans- and cis-chlordane, trans- and cis-nonachlor, p,p'- and o,p-DDT, DDD, DDE as well as hexachlorobenzene (HCB) were selected. The monitoring program with weekly samples taken during the period 2007-2010 was coordinated with the parallel program at the Norwegian Arctic monitoring site (Zeppelin mountain, Ny-Ålesund, Svalbard) in terms of priority compounds, sampling schedule as well as analytical methods. The POP concentration levels found in Antarctica were considerably lower than Arctic atmospheric background concentrations. Similar as observed for Arctic samples, HCB is the predominant POP compound with levels of around 22 pg m-3 throughout the entire monitoring period. In general, the following concentration distribution was found for the Troll samples analyzed: HCB > Sum HCH > Sum PCB > Sum DDT > Sum chlordanes. Atmospheric long-range transport was identified as a major contamination source for POPs in Antarctic environments. Several long-range transport events with elevated levels of pesticides and/or compounds with industrial sources were identified based on retroplume calculations with a Lagrangian particle dispersion model (FLEXPART). The POP levels determined in Troll air were compared with 1 concentrations found in earlier measurement campaigns at other Antarctic research stations from the past 18 yr. Except for HCB for which similar concentration distributions were observed in all sampling campaigns, concentrations in the recent Troll samples were lower than in samples collected during the early 1990s. These concentration reductions are obviously a direct consequence of international regulations restricting the usage of POP-like chemicals on a worldwide scale.

Étude de la variation spatio-temporelle des paramètres physico-chimiques caractérisant la qualité des eaux d'une lagune côtière et ses zonations écologiques : cas de Moulay Bousselham, Maroc

NASA Astrophysics Data System (ADS)

Labbardi, Hanane; Ettahiri, Omar; Lazar, Said; Massik, Zakia; El Antri, Said

2005-04-01

Our interest is related to the hydrological characteristics of the Moulay Bousselham lagoon. Water samples were taken monthly from July 2001 to June 2002 in 15 stations distributed along the lagoon. The various measured hydrological parameters (temperature, salinity, suspended matter, chlorophyll a) showed significant monthly variations ( p<0.001), whereas spatially among all sampled stations, only the salinity showed significant variations. The variability analysis approached by the analysis of the normalized principal components combined with discriminate analysis showed very small inter-stations variability. Its percentage is 11% and 9% of the total variance during high and low tide, respectively. To cite this article: H. Labbardi et al., C. R. Geoscience 337 (2005).

Estimation of the discharges of the multiple water level stations by multi-objective optimization

NASA Astrophysics Data System (ADS)

Matsumoto, Kazuhiro; Miyamoto, Mamoru; Yamakage, Yuzuru; Tsuda, Morimasa; Yanami, Hitoshi; Anai, Hirokazu; Iwami, Yoichi

2016-04-01

This presentation shows two aspects of the parameter identification to estimate the discharges of the multiple water level stations by multi-objective optimization. One is how to adjust the parameters to estimate the discharges accurately. The other is which optimization algorithms are suitable for the parameter identification. Regarding the previous studies, there is a study that minimizes the weighted error of the discharges of the multiple water level stations by single-objective optimization. On the other hand, there are some studies that minimize the multiple error assessment functions of the discharge of a single water level station by multi-objective optimization. This presentation features to simultaneously minimize the errors of the discharges of the multiple water level stations by multi-objective optimization. Abe River basin in Japan is targeted. The basin area is 567.0km2. There are thirteen rainfall stations and three water level stations. Nine flood events are investigated. They occurred from 2005 to 2012 and the maximum discharges exceed 1,000m3/s. The discharges are calculated with PWRI distributed hydrological model. The basin is partitioned into the meshes of 500m x 500m. Two-layer tanks are placed on each mesh. Fourteen parameters are adjusted to estimate the discharges accurately. Twelve of them are the hydrological parameters and two of them are the parameters of the initial water levels of the tanks. Three objective functions are the mean squared errors between the observed and calculated discharges at the water level stations. Latin Hypercube sampling is one of the uniformly sampling algorithms. The discharges are calculated with respect to the parameter values sampled by a simplified version of Latin Hypercube sampling. The observed discharge is surrounded by the calculated discharges. It suggests that it might be possible to estimate the discharge accurately by adjusting the parameters. In a sense, it is true that the discharge of a water level station can be accurately estimated by setting the parameter values optimized to the responding water level station. However, there are some cases that the calculated discharge by setting the parameter values optimized to one water level station does not meet the observed discharge at another water level station. It is important to estimate the discharges of all the water level stations in some degree of accuracy. It turns out to be possible to select the parameter values from the pareto optimal solutions by the condition that all the normalized errors by the minimum error of the responding water level station are under 3. The optimization performance of five implementations of the algorithms and a simplified version of Latin Hypercube sampling are compared. Five implementations are NSGA2 and PAES of an optimization software inspyred and MCO_NSGA2R, MOPSOCD and NSGA2R_NSGA2R of a statistical software R. NSGA2, PAES and MOPSOCD are the optimization algorithms of a genetic algorithm, an evolution strategy and a particle swarm optimization respectively. The number of the evaluations of the objective functions is 10,000. Two implementations of NSGA2 of R outperform the others. They are promising to be suitable for the parameter identification of PWRI distributed hydrological model.

Occurrence and Distribution of Organic Wastewater Compounds in Rock Creek Park, Washington, D.C., 2007-08

USGS Publications Warehouse

Phelan, Daniel J.; Miller, Cherie V.

2010-01-01

The U.S. Geological Survey, and the National Park Service Police Aviation Group, conducted a high-resolution, low-altitude aerial thermal infrared survey of the Washington, D.C. section of Rock Creek Basin within the Park boundaries to identify specific locations where warm water was discharging from seeps or pipes to the creek. Twenty-three stream sites in Rock Creek Park were selected based on the thermal infrared images. Sites were sampled during the summers of 2007 and 2008 for the analysis of organic wastewater compounds to verify potential sources of sewage and other anthropogenic wastewater. Two sets of stormwater samples were collected, on June 27-28 and September 6, 2008, at the Rock Creek at Joyce Road water-quality station using an automated sampler that began sampling when a specified stage threshold value was exceeded. Passive-sampler devices that accumulate organic chemicals over the duration of deployment were placed in July 2008 at the five locations that had the greatest number of detections of organic wastewater compounds from the June 2007 base-flow sampling. During the 2007 base-flow synoptic sampling, there were ubiquitous low-level detections of dissolved organic wastewater indicator compounds such as DEET, caffeine, HHCB, and organophosphate flame retardants at more than half of the 23 sites sampled in Rock Creek Park. Concentrations of DEET and caffeine in the tributaries to Rock Creek were variable, but in the main stem of Rock Creek, the concentrations were constant throughout the length of the creek, which likely reflects a distributed source. Organophosphate flame retardants in the main stem of Rock Creek were detected at estimated concentrations of 0.2 micrograms per liter or less, and generally did not increase with distance downstream. Overall, concentrations of most wastewater indicators in whole-water samples in the Park were similar to the concentrations found at the upstream sampling station at the Maryland/District of Columbia boundary. Polycyclic aromatic hydrocarbons were the dominant organic compounds found in the stormwater samples at the Joyce Road station. Polycyclic aromatic hydrocarbons were consistently found in higher concentrations either in sediment or in whole-water samples than in the dissolved samples collected during base-flow conditions at the 23 synoptic sites, or in the Joyce Road station stormwater samples.

Pacific Island landbird monitoring annual report, Haleakalā National Park, 2012

USGS Publications Warehouse

Judge, Seth W.; Camp, Richard J.; Hart, Patrick J.

2013-01-01

Haleakalā National Park (HALE) was surveyed for landbirds and habitat characteristics from March 20 through July 26, 2012. This information provides data in the time-series of landbird monitoring for long-term trends in forest bird distribution, density, and abundance. The Kīpahulu District of eastern Haleakalā Volcano was surveyed using point-transect distance sampling to estimate bird abundance. We surveyed 160 stations and detected a total of 2,830 birds from 12 species. Half of the species were native and half were non-native. Numbers of detections per species ranged from 1 to 849. There were sufficient detections of seven species to allow density estimation. Āpapane (Himatione sanguinea) was the most widely distributed and abundant native species detected in the survey. ‘Alauahio (Paroreomyza montana newtoni), Maui ‘Amakihi (Hemignathus virens wilsoni), and I‘iwi (Vestiaria coccinea) were widespread and occurred in relatively modest densities. Only eight Kiwikiu (Pseudonestor xanthophrys) and 20 ‘Ākohekohe (Palmeria dolei) were detected and were restricted to high elevation wet forest. We estimated an abundance of 495 ± 261individuals of Kiwikiu in a 2,036 ha inference area which likely includes the entire suitable habitat for this species in HALE. For ‘Ākohekohe, we estimated an abundance of 1,150 ± 389 individuals in the 1,458 ha inference area. There was a strong representation of non-native landbirds in the survey area. The Japanese White-eye (Zosterops japonicus), Japanese Bush-warbler (Cettia diphone), and Red-billed Leiothrix (Leiothrix lutea) accounted for nearly half of all landbird detections. Each species was common in predominantly native forests. Vegetation and topographic characteristics were recorded on 160 landbird monitoring stations. HALE canopy and understory composition was predominantly native, especially at elevations above 1,100 m. Much of the forest canopy was comprised of `ohi`a (Metrosideros polymorpha) interspersed with mature olapa (Cheirodendron platyphyllum). This canopy class occurred at 92.5% of the stations surveyed. More than three-quarters (77.5%) of the monitoring stations had a dense canopy with most crowns interlocking (> 60% cover). More than half (52%) of the stations surveyed had trees taller than 10 m, while almost a third (31%) had trees 5-10 m. Only 17% of the stations had a canopy shorter than 5 m. The native shrubs Vaccinium calycinum, Broussaisia arguta, and Leptecophylla tameiameae were the most common understory plants recorded, occurring at more than 30% of the stations sampled. Native mosses and ferns were also common at stations, occurring at more than 90% of the stations sampled. The invasive Psidium cattleainum, Clidemia hirta, and Hedychium gardnerianum occurred at approximately 14% of the stations sampled, predominantly at elevations below 1,100 m.

Possible health effects of liquefied petroleum gas on workers at filling and distribution stations of Gaza governorates.

PubMed

Sirdah, M M; Al Laham, N A; El Madhoun, R A

2013-03-01

Liquefied petroleum gas (LPG) is widely used in the Gaza Strip for domestic purposes, in agriculture and industry and, illegally, in cars. This study aimed to identify possible health effects on workers exposed to LPG in Gaza governorates. Data were collected by a questionnaire interview, and haematological and biochemical analyses of venous blood samples were made from 30 workers at filling and distribution stations and 30 apparently healthy controls. Statistically significant differences were found in all self-reported health-related complaints among LPG workers versus controls. LPG workers had significantly higher values of red blood cell counts, haemoglobin, haematocrit mean corpuscular haemoglobin and platelet counts. They also had significantly higher values of kidney function tests (urea, creatinine and uric acid) and liver function enzyme activities (aspartate aminotransferase and alanine aminotransferase). LPG workers at Gaza Strip petroleum stations are at higher risk for health-related symptoms and clinical abnormalities.

Areal extent of petroleum-related compounds from a gasoline and diesel-fuel leak in ground water at a site in Yakima, Washington, 1984-89

USGS Publications Warehouse

Wagner, R.J.

1995-01-01

A gasoline and diesel-fuel leak was discovered in the early 1980's at a service station in Yakima, Washington, and an attempt to recover the flee-floating petroleum product was unsuccessful. From 1984 through 1989, data were collected from observation wells drilled near the site of the leak and from nearby domestic wells during three separate studies. Between February 1985 and November 1986, benzene, toluene, xylenes, and other soluble compounds of petroleum origin were found at concentrations that exceeded standards for drinking water in all samples from observation wells within 300 feet of the service station. These compounds also were found in smaller concentrations in some samples from domestic wells as far as 1,500 feet downgradient of the service station. Concentrations of these soluble compounds in ground-water samples collected in March 1989 had decreased, and areal distribution of the compounds was smaller than when monitoring began in 1984.

A two-stage stochastic optimization model for scheduling electric vehicle charging loads to relieve distribution-system constraints

DOE PAGES

Wu, Fei; Sioshansi, Ramteen

2017-05-25

Electric vehicles (EVs) hold promise to improve the energy efficiency and environmental impacts of transportation. However, widespread EV use can impose significant stress on electricity-distribution systems due to their added charging loads. This paper proposes a centralized EV charging-control model, which schedules the charging of EVs that have flexibility. This flexibility stems from EVs that are parked at the charging station for a longer duration of time than is needed to fully recharge the battery. The model is formulated as a two-stage stochastic optimization problem. The model captures the use of distributed energy resources and uncertainties around EV arrival timesmore » and charging demands upon arrival, non-EV loads on the distribution system, energy prices, and availability of energy from the distributed energy resources. We use a Monte Carlo-based sample-average approximation technique and an L-shaped method to solve the resulting optimization problem efficiently. We also apply a sequential sampling technique to dynamically determine the optimal size of the randomly sampled scenario tree to give a solution with a desired quality at minimal computational cost. Here, we demonstrate the use of our model on a Central-Ohio-based case study. We show the benefits of the model in reducing charging costs, negative impacts on the distribution system, and unserved EV-charging demand compared to simpler heuristics. Lastly, we also conduct sensitivity analyses, to show how the model performs and the resulting costs and load profiles when the design of the station or EV-usage parameters are changed.« less

Application of spatial Poisson process models to air mass thunderstorm rainfall

NASA Technical Reports Server (NTRS)

Eagleson, P. S.; Fennessy, N. M.; Wang, Qinliang; Rodriguez-Iturbe, I.

1987-01-01

Eight years of summer storm rainfall observations from 93 stations in and around the 154 sq km Walnut Gulch catchment of the Agricultural Research Service, U.S. Department of Agriculture, in Arizona are processed to yield the total station depths of 428 storms. Statistical analysis of these random fields yields the first two moments, the spatial correlation and variance functions, and the spatial distribution of total rainfall for each storm. The absolute and relative worth of three Poisson models are evaluated by comparing their prediction of the spatial distribution of storm rainfall with observations from the second half of the sample. The effect of interstorm parameter variation is examined.

The nature of the data

NASA Technical Reports Server (NTRS)

1981-01-01

The locations of total ozone stations and of stratospheric ozone samplings were presented. The samplings are concentrated in three areas: Japan, Europe, and India. Approximately 75% of the total ozone measurements are made with Dobson instruments which offer the best international measurements. When well calibrated their accuracy is on the order of a few percent. It is found that although the total ozone percent is similar in both hemispheres, the northern hemisphere has 3 to 10% more ozone than the southern hemisphere. The close association between total ozone distribution and pressure distribution in the atmosphere is noted.

Surface-water-quality assessment of the upper Illinois River Basin in Illinois, Indiana, and Wisconsin; data on agricultural organic compounds, nutrients, and sediment in water, 1988-90

USGS Publications Warehouse

Sullivan, D.J.; Terrio, P.J.

1994-01-01

This report describes the sampling design and methods and presents data collected to determine the distribution of agricultural organic compounds, nutrients, and sediment in selected areas of the upper Illinois River Basin as part of the National Water-Quality Assessment program. Four stations in small watersheds (two urban, two agricultural) were sampled in 1988 and 1989. Seventeen stations in an agricultural subbasin were sampled in 1990. Samples were collected before, during, and after runoff events from late spring to midsummer to determine concentrations of agricultural organic compounds in surface waters resulting from storm runoff, as well as background concentrations. Over 200 water samples were analyzed for agricultural organic compound, nutrient, and suspended-sediment concentrations. The agricultural organic compounds included triazine and chlorophenoxy-acid herbicides, and organo-phosphorus insecticides.

Ground-based instruments of the PWING project to investigate dynamics of the inner magnetosphere at subauroral latitudes as a part of the ERG-ground coordinated observation network

NASA Astrophysics Data System (ADS)

Shiokawa, Kazuo; Katoh, Yasuo; Hamaguchi, Yoshiyuki; Yamamoto, Yuka; Adachi, Takumi; Ozaki, Mitsunori; Oyama, Shin-Ichiro; Nosé, Masahito; Nagatsuma, Tsutomu; Tanaka, Yoshimasa; Otsuka, Yuichi; Miyoshi, Yoshizumi; Kataoka, Ryuho; Takagi, Yuki; Takeshita, Yuhei; Shinbori, Atsuki; Kurita, Satoshi; Hori, Tomoaki; Nishitani, Nozomu; Shinohara, Iku; Tsuchiya, Fuminori; Obana, Yuki; Suzuki, Shin; Takahashi, Naoko; Seki, Kanako; Kadokura, Akira; Hosokawa, Keisuke; Ogawa, Yasunobu; Connors, Martin; Michael Ruohoniemi, J.; Engebretson, Mark; Turunen, Esa; Ulich, Thomas; Manninen, Jyrki; Raita, Tero; Kero, Antti; Oksanen, Arto; Back, Marko; Kauristie, Kirsti; Mattanen, Jyrki; Baishev, Dmitry; Kurkin, Vladimir; Oinats, Alexey; Pashinin, Alexander; Vasilyev, Roman; Rakhmatulin, Ravil; Bristow, William; Karjala, Marty

2017-11-01

The plasmas (electrons and ions) in the inner magnetosphere have wide energy ranges from electron volts to mega-electron volts (MeV). These plasmas rotate around the Earth longitudinally due to the gradient and curvature of the geomagnetic field and by the co-rotation motion with timescales from several tens of hours to less than 10 min. They interact with plasma waves at frequencies of mHz to kHz mainly in the equatorial plane of the magnetosphere, obtain energies up to MeV, and are lost into the ionosphere. In order to provide the global distribution and quantitative evaluation of the dynamical variation of these plasmas and waves in the inner magnetosphere, the PWING project (study of dynamical variation of particles and waves in the inner magnetosphere using ground-based network observations, http://www.isee.nagoya-u.ac.jp/dimr/PWING/) has been carried out since April 2016. This paper describes the stations and instrumentation of the PWING project. We operate all-sky airglow/aurora imagers, 64-Hz sampling induction magnetometers, 40-kHz sampling loop antennas, and 64-Hz sampling riometers at eight stations at subauroral latitudes ( 60° geomagnetic latitude) in the northern hemisphere, as well as 100-Hz sampling EMCCD cameras at three stations. These stations are distributed longitudinally in Canada, Iceland, Finland, Russia, and Alaska to obtain the longitudinal distribution of plasmas and waves in the inner magnetosphere. This PWING longitudinal network has been developed as a part of the ERG (Arase)-ground coordinated observation network. The ERG (Arase) satellite was launched on December 20, 2016, and has been in full operation since March 2017. We will combine these ground network observations with the ERG (Arase) satellite and global modeling studies. These comprehensive datasets will contribute to the investigation of dynamical variation of particles and waves in the inner magnetosphere, which is one of the most important research topics in recent space physics, and the outcome of our research will improve safe and secure use of geospace around the Earth.[Figure not available: see fulltext.

An analysis of annual maximum streamflows in Terengganu, Malaysia using TL-moments approach

NASA Astrophysics Data System (ADS)

Ahmad, Ummi Nadiah; Shabri, Ani; Zakaria, Zahrahtul Amani

2013-02-01

TL-moments approach has been used in an analysis to determine the best-fitting distributions to represent the annual series of maximum streamflow data over 12 stations in Terengganu, Malaysia. The TL-moments with different trimming values are used to estimate the parameter of the selected distributions namely: generalized pareto (GPA), generalized logistic, and generalized extreme value distribution. The influence of TL-moments on estimated probability distribution functions are examined by evaluating the relative root mean square error and relative bias of quantile estimates through Monte Carlo simulations. The boxplot is used to show the location of the median and the dispersion of the data, which helps in reaching the decisive conclusions. For most of the cases, the results show that TL-moments with one smallest value was trimmed from the conceptual sample (TL-moments (1,0)), of GPA distribution was the most appropriate in majority of the stations for describing the annual maximum streamflow series in Terengganu, Malaysia.

An illustrated key to the soft-bottom caprellids (Crustacea: Amphipoda) of the Iberian Peninsula and remarks to their ecological distribution along the Andalusian coast

NASA Astrophysics Data System (ADS)

Guerra-García, José M.; Navarro-Barranco, Carlos; Corzo, Juan; Cobos-Muñoz, Vanessa; García-Adiego, Emilio M.; Giménez, Francisco Sempere; García-Gómez, J. Carlos

2013-06-01

The soft-bottom caprellids of the Iberian Peninsula are revised. Nineteen species have been reported so far, 42 % being endemic to the Mediterranean Sea. The lateral view of all of them is provided, together with an illustrated key for all the species. An ecological study was also conducted during 2007-2010 along the Andalusian coast to explore the relationships of caprellids with abiotic data. A total of 90 stations (0-40 m deep) were sampled and 40 contained caprellids. Along the Atlantic, caprellids were present in only 20 % of the stations, while along the Mediterranean coast, caprellids were present in the 75 % of the sampling sites. Furthermore, the abundance of caprellids was also higher in the Mediterranean coast. The dominant species was Pseudolirius kroyeri (present in 24 stations and showing the highest abundances with 1,780 ind/m2), followed by Phtisica marina (22 stations) and Pariambus typicus (11 stations). According to CCA and BIO-ENV, sediment type, P, pH and oxygen were the parameters that better explained the distribution of caprellids. Although the three dominant species were found in all types of sediment, the univariate approach showed that P. kroyeri was significantly more abundant in fine sediments (silt-clay and very fine sands) than in gross sediments (coarse and very coarse sands). The majority of studies dealing with caprellids from the Iberian Peninsula have been focused on shallow waters and further efforts are needed to explore biodiversity of deeper areas.

Benthic Foraminifera As A Novel Bio-monitoring Tool In The Assessment Of Environmental Impacts Linked To Marine Aquaculture

NASA Astrophysics Data System (ADS)

Alammar, Montaha; Austin, William

2017-04-01

The present study represents an attempt to evaluate the impacts of marine aquaculture on benthic foraminiferal communities in order to develop an improved, quantitative understanding of their response to the variation in benthic environmental gradients associated with fish farms in Scotland. Furthermore, their performance as a bio-monitoring tool will be discussed and outlined in ongoing research to evaluate their performance alongside traditional bioecological indicators. Foraminiferal faunas offer the potential to assess ecological quality status through their response to stress gradients (e.g. organic matter enrichment), such as that caused by intensive fish farming in coastal sediments. In this study, we followed the Foraminiferal Bio-Monitoring (FOBIMO) protocol (Schönfeld. et al., 2012), which proposed a standardised methodology of using foraminifera as a bio-monitoring tool to evaluate the quality of the marine ecosystem and applied these protocols to the rapidly expanding marine aquaculture sector in Scotland, UK. Eight stations were sampled along a transect in Loch Creran, west coast of Scotland, to describe the spatial and down-core (temporal) distribution pattern of benthic foraminiferal assemblages. Triplicate, Rose-Bengal stained samples from an interval of (0-1cm) below the sediment surface were studied at each station from below the fish cages (impacted stations) to a distance from the farming sites (control stations). Morphospecies counts were conducted, and the organic carbon and the grain size distributions determined. Species richness beneath these fish farming cages were analysed and showed a reduction of foraminifera density and diversity at the impacted stations.

The distribution and diversity of benthic macroinvertebrate fauna in Pondicherry mangroves, India

PubMed Central

2013-01-01

Background Species distribution, abundance and diversity of mangrove benthic macroinvertebrate fauna and the relationships to environmental conditions are important parts of understanding the structure and function of mangrove ecosystems. In this study seasonal variation in the distribution of macrobenthos and related environmental parameters were explored at four mangrove stations along the Pondicherry coast of India, from September 2008 to July 2010. Multivariate statistical analyses, including cluster analysis, principal component analysis and non-multidimensional scales plot were employed to help define trophic status, water quality and benthic characteristic at the four monitoring stations. Results Among the 528 samples collected over 168 ha of mangrove forest 76 species of benthic macroinvertebrate fauna were identified. Macrofauna were mainly composed of deposit feeders, dominated numerically by molluscs and crustaceans. Statistical analyses yielded the following descriptors of benthic macroinvertebrate fauna species distribution: densities between 140–1113 ind. m-2, dominance 0.17-0.50, diversity 1.80-2.83 bits ind-1, richness 0.47-0.74 and evenness 0.45-0.72, equitability 0.38-0.77, berger parker 0.31-0.77 and fisher alpha 2.46-5.70. Increases of species diversity and abundance were recorded during the post monsoon season at station 1 and the lowest diversity was recorded at station 2 during the monsoon season. The pollution indicator organisms Cassidula nucleus, Melampus ceylonicus, Sphaerassiminea minuta were found only at the two most polluted regions, i.e. stations 3 and 4. Benthic macroinvertebrate fauna abundances were inversely related to salinity at the four stations, Based on Bray-Curtis similarity through hierarchical clustering implemented in PAST, it was possible to define three distinct benthic assemblages at the stations. Conclusions From a different multivariate statistical analysis of the different environmental parameters regarding species diversity and abundance of benthic macroinvertebrate fauna, it was found that benthic communities are highly affected by all the environmental parameters governing the distribution and diversity variation of the macrofaunal community in Pondicherry mangroves. Salinity, dissolved oxygen levels, organic matter content, sulphide concentration were the most significant parameters. PMID:23937801

Abundance, distribution and diversity of gelatinous predators along the northern Mid-Atlantic Ridge: A comparison of different sampling methodologies

PubMed Central

Falkenhaug, Tone; Baxter, Emily J.

2017-01-01

The diversity and distribution of gelatinous zooplankton were investigated along the northern Mid-Atlantic Ridge (MAR) from June to August 2004.Here, we present results from macrozooplankton trawl sampling, as well as comparisons made between five different methodologies that were employed during the MAR-ECO survey. In total, 16 species of hydromedusae, 31 species of siphonophores and four species of scyphozoans were identified to species level from macrozooplankton trawl samples. Additional taxa were identified to higher taxonomic levels and a single ctenophore genus was observed. Samples were collected at 17 stations along the MAR between the Azores and Iceland. A divergence in the species assemblages was observed at the southern limit of the Subpolar Frontal Zone. The catch composition of gelatinous zooplankton is compared between different sampling methodologies including: a macrozooplankton trawl; a Multinet; a ringnet attached to bottom trawl; and optical platforms (Underwater Video Profiler (UVP) & Remotely Operated Vehicle (ROV)). Different sampling methodologies are shown to exhibit selectivity towards different groups of gelatinous zooplankton. Only ~21% of taxa caught during the survey were caught by both the macrozooplankton trawl and the Multinet when deployed at the same station. The estimates of gelatinous zooplankton abundance calculated using these two gear types also varied widely (1.4 ± 0.9 individuals 1000 m-3 estimated by the macrozooplankton trawl vs. 468.3 ± 315.4 individuals 1000 m-3 estimated by the Multinet (mean ± s.d.) when used at the same stations (n = 6). While it appears that traditional net sampling can generate useful data on pelagic cnidarians, comparisons with results from the optical platforms suggest that ctenophore diversity and abundance are consistently underestimated, particularly when net sampling is conducted in combination with formalin fixation. The results emphasise the importance of considering sampling methodology both when planning surveys, as well as when interpreting existing data. PMID:29095891

Abundance, distribution and diversity of gelatinous predators along the northern Mid-Atlantic Ridge: A comparison of different sampling methodologies.

PubMed

Hosia, Aino; Falkenhaug, Tone; Baxter, Emily J; Pagès, Francesc

2017-01-01

The diversity and distribution of gelatinous zooplankton were investigated along the northern Mid-Atlantic Ridge (MAR) from June to August 2004.Here, we present results from macrozooplankton trawl sampling, as well as comparisons made between five different methodologies that were employed during the MAR-ECO survey. In total, 16 species of hydromedusae, 31 species of siphonophores and four species of scyphozoans were identified to species level from macrozooplankton trawl samples. Additional taxa were identified to higher taxonomic levels and a single ctenophore genus was observed. Samples were collected at 17 stations along the MAR between the Azores and Iceland. A divergence in the species assemblages was observed at the southern limit of the Subpolar Frontal Zone. The catch composition of gelatinous zooplankton is compared between different sampling methodologies including: a macrozooplankton trawl; a Multinet; a ringnet attached to bottom trawl; and optical platforms (Underwater Video Profiler (UVP) & Remotely Operated Vehicle (ROV)). Different sampling methodologies are shown to exhibit selectivity towards different groups of gelatinous zooplankton. Only ~21% of taxa caught during the survey were caught by both the macrozooplankton trawl and the Multinet when deployed at the same station. The estimates of gelatinous zooplankton abundance calculated using these two gear types also varied widely (1.4 ± 0.9 individuals 1000 m-3 estimated by the macrozooplankton trawl vs. 468.3 ± 315.4 individuals 1000 m-3 estimated by the Multinet (mean ± s.d.) when used at the same stations (n = 6). While it appears that traditional net sampling can generate useful data on pelagic cnidarians, comparisons with results from the optical platforms suggest that ctenophore diversity and abundance are consistently underestimated, particularly when net sampling is conducted in combination with formalin fixation. The results emphasise the importance of considering sampling methodology both when planning surveys, as well as when interpreting existing data.

Quality of stormwater runoff discharged from Massachusetts highways, 2005-07

USGS Publications Warehouse

Smith, Kirk P.; Granato, Gregory E.

2010-01-01

The U.S. Geological Survey (USGS), in cooperation with U.S. Department of Transportation Federal Highway Administration and the Massachusetts Department of Transportation, conducted a field study from September 2005 through September 2007 to characterize the quality of highway runoff for a wide range of constituents. The highways studied had annual average daily traffic (AADT) volumes from about 3,000 to more than 190,000 vehicles per day. Highway-monitoring stations were installed at 12 locations in Massachusetts on 8 highways. The 12 monitoring stations were subdivided into 4 primary, 4 secondary, and 4 test stations. Each site contained a 100-percent impervious drainage area that included two or more catch basins sharing a common outflow pipe. Paired primary and secondary stations were located within a few miles of each other on a limited-access section of the same highway. Most of the data were collected at the primary and secondary stations, which were located on four principal highways (Route 119, Route 2, Interstate 495, and Interstate 95). The secondary stations were operated simultaneously with the primary stations for at least a year. Data from the four test stations (Route 8, Interstate 195, Interstate 190, and Interstate 93) were used to determine the transferability of the data collected from the principal highways to other highways characterized by different construction techniques, land use, and geography. Automatic-monitoring techniques were used to collect composite samples of highway runoff and make continuous measurements of several physical characteristics. Flowweighted samples of highway runoff were collected automatically during approximately 140 rain and mixed rain, sleet, and snowstorms. These samples were analyzed for physical characteristics and concentrations of 6 dissolved major ions, total nutrients, 8 total-recoverable metals, suspended sediment, and 85 semivolatile organic compounds (SVOCs), which include priority polyaromatic hydrocarbons (PAHs), phthalate esters, and other anthropogenic or naturally occurring organic compounds. The distribution of particle size of suspended sediment also was determined for composite samples of highway runoff. Samples of highway runoff were collected year round and under various dry antecedent conditions throughout the 2-year sampling period. In addition to samples of highway runoff, supplemental samples also were collected of sediment in highway runoff, background soils, berm materials, maintenance sands, deicing compounds, and vegetation matter. These additional samples were collected near or on the highways to support data analysis. There were few statistically significant differences between populations of constituent concentrations in samples from the primary and secondary stations on the same principal highways (Mann-Whitney test, 95-percent confidence level). Similarly, there were few statistically significant differences between populations of constituent concentrations for the four principal highways (data from the paired primary and secondary stations for each principal highway) and populations for test stations with similar AADT volumes. Exceptions to this include several total-recoverable metals for stations on Route 2 and Interstate 195 (highways with moderate AADT volumes), and for stations on Interstate 95 and Interstate 93 (highways with high AADT volumes). Supplemental data collected during this study indicate that many of these differences may be explained by the quantity, as well as the quality, of the sediment in samples of highway runoff. Nonparametric statistical methods also were used to test for differences between populations of sample constituent concentrations among the four principal highways that differed mainly in traffic volume. These results indicate that there were few statistically significant differences (Mann-Whitney test, 95-percent confidence level) for populations of concentrations of most total-recoverable metals

Real-Time Data Management, IP Telemetry, Data Integration, and Data Center Operations for the Source Physics Experiment (SPE), Nevada National Security Site

NASA Astrophysics Data System (ADS)

Plank, G.; Slater, D.; Torrisi, J.; Presser, R.; Williams, M.; Smith, K. D.

2012-12-01

The Nevada Seismological Laboratory (NSL) manages time-series data and high-throughput IP telemetry for the National Center for Nuclear Security (NCNS) Source Physics Experiment (SPE), underway on the Nevada National Security Site (NNSS). During active-source experiments, SPE's heterogeneous systems record over 350 channels of a variety of data types including seismic, infrasound, acoustic, and electro-magnetic. During the interim periods, broadband and short period instruments record approximately 200 channels of continuous, high-sample-rate seismic data. Frequent changes in sensor and station configurations create a challenging meta-data environment. Meta-data account for complete operational histories, including sensor types, serial numbers, gains, sample rates, orientations, instrument responses, data-logger types etc. To date, these catalogue 217 stations, over 40 different sensor types, and over 1000 unique recording configurations (epochs). Facilities for processing, backup, and distribution of time-series data currently span four Linux servers, 60Tb of disk capacity, and two data centers. Bandwidth, physical security, and redundant power and cooling systems for acquisition, processing, and backup servers are provided by NSL's Reno data center. The Nevada System of Higher Education (NSHE) System Computer Services (SCS) in Las Vegas provides similar facilities for the distribution server. NSL staff handle setup, maintenance, and security of all data management systems. SPE PIs have remote access to meta-data, raw data, and CSS3.0 compilations, via SSL-based transfers such as rsync or secure-copy, as well as shell access for data browsing and limited processing. Meta-data are continuously updated and posted on the Las Vegas distribution server as station histories are better understood and errors are corrected. Raw time series and refined CSS3.0 data compilations with standardized formats are transferred to the Las Vegas data server as available. For better data availability and station monitoring, SPE is beginning to leverage NSL's wide-area digital IP network with nine SPE stations and six Rock Valley area stations that stream continuous recordings in real time to the NSL Reno data center. These stations, in addition to eight regional legacy stations supported by National Security Technologies (NSTec), are integrated with NSL's regional monitoring network and constrain a high-quality local earthquake catalog for NNSS. The telemetered stations provide critical capabilities for SPE, and infrastructure for earthquake response on NNSS as well as southern Nevada and the Las Vegas area.

Jellies under ice: ROV observations from the Arctic 2005 hidden ocean expedition

NASA Astrophysics Data System (ADS)

Raskoff, K. A.; Hopcroft, R. R.; Kosobokova, K. N.; Purcell, J. E.; Youngbluth, M.

2010-01-01

In order to provide a baseline understanding of gelatinous zooplankton biodiversity and distribution in the rapidly changing Arctic Ocean, 12 stations were sampled across the Canada Basin, Northwind Ridge, and Chukchi Plateau with detailed deep-water ROV observations and multinet tows down to 3000 m. The complex, multi-origin water layers of the Arctic Ocean provided the backdrop for examining the vertical and horizontal distributions of the poorly understood meso and bathypelagic gelatinous taxa. Over 50 different gelatinous taxa were observed across the stations, with cnidarians being the most common group. Medusae accounted for 60% of all observations, siphonophores for 24%, larvaceans for 10%, ctenophores for 5%, and numerous interesting and rarer taxa constituted the remaining 1% of observations. Several new species were found and many major range extensions were observed. Both the vertical and horizontal distribution of species appear to be linked to water mass characteristics, as well as bottom topography and geographic location within the study area. Shallow slope and ridge areas around the Canada Basin and Chukchi Plateau appear to harbor substantially lower gelatinous zooplankton biomass and diversity than the deeper locations. Shallow stations not only show reduced abundance, but also different relative abundance of the major taxa, where the shallow water stations are dominated by large numbers of siphonophores and ctenophores, the deep stations are dominated by medusae. Taxonomic issues and ecological observations of several important species are discussed, aided by the live collection of many undamaged and fragile species.

CDOM Distribution and Dynamics in a Mangrove Ecosystem along the Shark River, Florida Everglades

NASA Astrophysics Data System (ADS)

Andrew, A. A.; del Castillo, C. E.

2016-02-01

Mangrove forests, a fraction of tropical forest, are in general a disproportionately important component in the global carbon cycle. Mangroves are highly productive, sequestering CO2 at rates higher than many other ecosystems, however more than half of this fixed carbon cannot be accounted for. Additionally, as they sit at the intersection of land and ocean, it's hypothesized that a large fraction of DOC transformations occur in these ecosystems and represent a major sink of terrigenous DOM. These factors highlight the importance of understanding mangrove environments in terms of DOM optical signals as well as reactivity upon light absorption. Here, we present the CDOM dynamics and distribution for a mangrove ecosystem in the Shark River, along the Southwest coast of Florida, part of the largest contiguous mangrove forest in North America. Station sampling of the study area occurred over 4 cruises, approximately one week in length: October 2014, March 2015, July 2015 and September 2015. Most of the stations were along the Shark River, with a smaller number in the vicinity of Tarpon bay and Harney River. Optical measurements of CDOM absorption and fluorescence, fluorescence quantum yields, DOC and spectral slope were obtained for over 70 stations in the study area. The spatial distribution of these optical properties are presented including their relation to salinity and tidal patterns in the study area. Additionally, we present the wavelength dependent quantum photoproduction efficiencies of DIC obtained via irradiation experiments of selective samples in the study area.

Population fluctuation and vertical distribution of meiofauna in the Red Sea interstitial environment.

PubMed

El-Serehy, Hamed A; Al-Misned, Fahad A; Al-Rasheid, Khaled A

2015-07-01

The composition and distribution of the benthic meiofauna assemblages of the Egyptian coasts along the Red Sea are described in relation to abiotic variables. Sediment samples were collected seasonally from three stations chosen along the Red Sea to observe the meiofaunal community structure, its temporal distribution and vertical fluctuation in relation to environmental conditions of the Red Sea marine ecosystem. The temperature, salinity, pH, dissolved oxygen, and redox potential were measured at the time of collection. The water content of the sediments, total organic matters and chlorophyll a values were determined, and sediment samples were subjected to granulometric analysis. A total of 10 meiofauna taxa were identified, with the meiofauna being primarily represented by nematodes (on annual average from 42% to 84%), harpacticoids, polycheates and ostracodes; and the meiofauna abundances ranging from 41 to 167 ind./10 cm(2). The meiofaunal population density fluctuated seasonally with a peak of 192.52 ind./10 cm(2) during summer at station II. The vertical zonation in the distribution of meiofaunal community was significantly correlated with interstitial water, chlorophyll a and total organic matter values. The present study indicates the existence of the well diversified meiofaunal group which can serve as food for higher trophic levels in the Red Sea interstitial environment.

Complex depth-related patterns in taxonomic and functional diversity of polychaetes in the Gulf of Mexico

NASA Astrophysics Data System (ADS)

Carvalho, Russell; Wei, Chih-Lin; Rowe, Gilbert; Schulze, Anja

2013-10-01

Patterns of taxonomic and functional diversity in polychaete assemblages were examined in the deep northern Gulf of Mexico, including the first analysis of polychaete feeding guild distribution. An analysis of samples from a total of 51 stations located along 7 transects plus additional nearby sites, indicated that density decreased exponentially with depth, with the central locations having higher densities than the eastern and western regions. Alpha diversity was also highest at the central stations associated with the Mississippi trough. The samples can be grouped into three significant clusters based on thirty percent similarity of species composition. BIO-ENV indicated depth, sediment particle size, and export POC were most important variables explaining distributions. The diversity of polychaete feeding guilds was high in the Mississippi trough, upper and mid-slope regions but declined to a few guilds on the Sigsbee abyssal plain. Combining feeding guild analysis with traditional analysis of species diversity contributes to a clearer understanding of trophic diversity in deep-sea benthic assemblages.

Estuarine water quality in parks of the Northeast Coastal and Barrier Network: Development and early implementation of vital signs estuarine nutrient-enrichment monitoring, 2003-06

USGS Publications Warehouse

Kopp, Blaine S.; Nielsen, Martha; Glisic, Dejan; Neckles, Hilary A.

2009-01-01

This report documents results of pilot tests of a protocol for monitoring estuarine nutrient enrichment for the Vital Signs Monitoring Program of the National Park Service Northeast Coastal and Barrier Network. Data collected from four parks during protocol development in 2003-06 are presented: Gateway National Recreation Area, Colonial National Historic Park, Fire Island National Seashore, and Assateague Island National Seashore. The monitoring approach incorporates several spatial and temporal designs to address questions at a hierarchy of scales. Indicators of estuarine response to nutrient enrichment were sampled using a probability design within park estuaries during a late-summer index period. Monitoring variables consisted of dissolved-oxygen concentration, chlorophyll a concentration, water temperature, salinity, attenuation of downwelling photosynthetically available radiation (PAR), and turbidity. The statistical sampling design allowed the condition of unsampled locations to be inferred from the distribution of data from a set of randomly positioned "probability" stations. A subset of sampling stations was sampled repeatedly during the index period, and stations were not rerandomized in subsequent years. These "trend stations" allowed us to examine temporal variability within the index period, and to improve the sensitivity of the monitoring protocol to detecting change through time. Additionally, one index site in each park was equipped for continuous monitoring throughout the index period. Thus, the protocol includes elements of probabilistic and targeted spatial sampling, and the temporal intensity ranges from snapshot assessments to continuous monitoring.

An investigation of the space distribution of Ulva microscopic propagules and ship-based experiment of mitigation using modified clay.

PubMed

Li, Jing; Song, Xiuxian; Zhang, Yue; Pan, Jun; Yu, Zhiming

2017-04-15

Previous studies suggested that the removal of Ulva microscopic propagules (UMP) from cradle water might restrict the formation and expansion of green tides in the Yellow Sea, China. In this study, the distribution characteristics of UMP in the southern Yellow Sea was investigated, and then a flocculation experiment of UMP using modified clay (MC) was conducted at a selected station of the research cruise. The results indicated that the distribution of green algae thalli is one of the main factors that directly influence UMP distribution. UMP density was strongly negatively correlated with the distance between the sampling station and the centre of the area containing floating Ulva (r=-0.618***, n=83). >80% of the UMP was removed from the water column after MC application at a concentration of 0.1g/L, and MC applied at a concentration of 0.5g/L reduced the germination rate to 0.3%. Copyright © 2017 Elsevier Ltd. All rights reserved.

A distributed planning concept for Space Station payload operations

NASA Technical Reports Server (NTRS)

Hagopian, Jeff; Maxwell, Theresa; Reed, Tracey

1994-01-01

The complex and diverse nature of the payload operations to be performed on the Space Station requires a robust and flexible planning approach. The planning approach for Space Station payload operations must support the phased development of the Space Station, as well as the geographically distributed users of the Space Station. To date, the planning approach for manned operations in space has been one of centralized planning to the n-th degree of detail. This approach, while valid for short duration flights, incurs high operations costs and is not conducive to long duration Space Station operations. The Space Station payload operations planning concept must reduce operations costs, accommodate phased station development, support distributed users, and provide flexibility. One way to meet these objectives is to distribute the planning functions across a hierarchy of payload planning organizations based on their particular needs and expertise. This paper presents a planning concept which satisfies all phases of the development of the Space Station (manned Shuttle flights, unmanned Station operations, and permanent manned operations), and the migration from centralized to distributed planning functions. Identified in this paper are the payload planning functions which can be distributed and the process by which these functions are performed.

Occurrence of microbial indicators and Clostridium perfringens in wastewater, water column samples, sediments, drinking water, and Weddell seal feces collected at McMurdo Station, Antarctica

USGS Publications Warehouse

Lisle, J.T.; Smith, J.J.; Edwards, D.D.; McFeters, G.A.

2004-01-01

McMurdo Station, Antarctica, has discharged untreated sewage into McMurdo Sound for decades. Previous studies delineated the impacted area, which included the drinking water intake, by using total coliform and Clostridium perfringens concentrations. The estimation of risk to humans in contact with the impacted and potable waters may be greater than presumed, as these microbial indicators may not be the most appropriate for this environment. To address these concerns, concentrations of these and additional indicators (fecal coliforms, Escherichia coli, enterococci, coliphage, and enteroviruses) in the untreated wastewater, water column, and sediments of the impacted area and drinking water treatment facility and distribution system at McMurdo Station were determined. Fecal samples from Weddell seals in this area were also collected and analyzed for indicators. All drinking water samples were negative for indicators except for a single total coliform-positive sample. Total coliforms were present in water column samples at higher concentrations than other indicators. Fecal coliform and enterococcus concentrations were similar to each other and greater than those of other indicators in sediment samples closer to the discharge site. C. perfringens concentrations were higher in sediments at greater distances from the discharge site. Seal fecal samples contained concentrations of fecal coliforms, E. coli, enterococci, and C. perfringens similar to those found in untreated sewage. All samples were negative for enteroviruses. A wastewater treatment facility at McMurdo Station has started operation, and these data provide a baseline data set for monitoring the recovery of the impacted area. The contribution of seal feces to indicator concentrations in this area should be considered.

Reconciling Streamflow Uncertainty Estimation and River Bed Morphology Dynamics. Insights from a Probabilistic Assessment of Streamflow Uncertainties Using a Reliability Diagram

NASA Astrophysics Data System (ADS)

Morlot, T.; Mathevet, T.; Perret, C.; Favre Pugin, A. C.

2014-12-01

Streamflow uncertainty estimation has recently received a large attention in the literature. A dynamic rating curve assessment method has been introduced (Morlot et al., 2014). This dynamic method allows to compute a rating curve for each gauging and a continuous streamflow time-series, while calculating streamflow uncertainties. Streamflow uncertainty takes into account many sources of uncertainty (water level, rating curve interpolation and extrapolation, gauging aging, etc.) and produces an estimated distribution of streamflow for each days. In order to caracterise streamflow uncertainty, a probabilistic framework has been applied on a large sample of hydrometric stations of the Division Technique Générale (DTG) of Électricité de France (EDF) hydrometric network (>250 stations) in France. A reliability diagram (Wilks, 1995) has been constructed for some stations, based on the streamflow distribution estimated for a given day and compared to a real streamflow observation estimated via a gauging. To build a reliability diagram, we computed the probability of an observed streamflow (gauging), given the streamflow distribution. Then, the reliability diagram allows to check that the distribution of probabilities of non-exceedance of the gaugings follows a uniform law (i.e., quantiles should be equipropables). Given the shape of the reliability diagram, the probabilistic calibration is caracterised (underdispersion, overdispersion, bias) (Thyer et al., 2009). In this paper, we present case studies where reliability diagrams have different statistical properties for different periods. Compared to our knowledge of river bed morphology dynamic of these hydrometric stations, we show how reliability diagram gives us invaluable information on river bed movements, like a continuous digging or backfilling of the hydraulic control due to erosion or sedimentation processes. Hence, the careful analysis of reliability diagrams allows to reconcile statistics and long-term river bed morphology processes. This knowledge improves our real-time management of hydrometric stations, given a better caracterisation of erosion/sedimentation processes and the stability of hydrometric station hydraulic control.

Tsunami Size Distributions at Far-Field Locations from Aggregated Earthquake Sources

NASA Astrophysics Data System (ADS)

Geist, E. L.; Parsons, T.

2015-12-01

The distribution of tsunami amplitudes at far-field tide gauge stations is explained by aggregating the probability of tsunamis derived from individual subduction zones and scaled by their seismic moment. The observed tsunami amplitude distributions of both continental (e.g., San Francisco) and island (e.g., Hilo) stations distant from subduction zones are examined. Although the observed probability distributions nominally follow a Pareto (power-law) distribution, there are significant deviations. Some stations exhibit varying degrees of tapering of the distribution at high amplitudes and, in the case of the Hilo station, there is a prominent break in slope on log-log probability plots. There are also differences in the slopes of the observed distributions among stations that can be significant. To explain these differences we first estimate seismic moment distributions of observed earthquakes for major subduction zones. Second, regression models are developed that relate the tsunami amplitude at a station to seismic moment at a subduction zone, correcting for epicentral distance. The seismic moment distribution is then transformed to a site-specific tsunami amplitude distribution using the regression model. Finally, a mixture distribution is developed, aggregating the transformed tsunami distributions from all relevant subduction zones. This mixture distribution is compared to the observed distribution to assess the performance of the method described above. This method allows us to estimate the largest tsunami that can be expected in a given time period at a station.

Epipelagic mesozooplankton succession and community structure over a marine ouffall area in the northeastern South China Sea.

PubMed

Tseng, Li Chun; Kumar, Ram; Dahms, Hans Uwe; Chen, Chun Te; Chen, Qing Chao; Hwang, Jiang Shiou

2008-05-01

This study analyses distribution and abundance patterns of mesozooplankton communities at 13 stations in the coastal waters over a marine outfall area in the northeastern South China Sea. Cruises were conducted in March, June and September 2002, and plankton samples were collected with a 333 microm North Pacific net. The Mesozooplankton was dominated by calanoid Copepods, Cladocera, Chaetognatha and Pteropoda. Stations located near the entrance of the harbor provided a relatively higher abundance of Noctilucales and Radiolarians. In total, 20 zooplankton groups were identified in which, Calanoida, Cladocera, Chaetognatha, Pteropoda, Poecilostomatoida and Appendicularia comprised 92.77% of the total zooplankton abundance. Copepoda dominated in all three cruises, comprising 65.32% of the total mesozooplankton abundance. Samples collected in June recorded higher mesozooplankton abundance than March and September samples. Onshore stations recorded higher BOD values, higher abundance of Noctilucales and Radiolarians and a relativelylower abundance of the overall mesozooplankton. Total mesozooplankton abundance did not correlate significantly with temperature, pH, or dissolved oxygen, but correlated negatively with BOD.

Identification of a potential toxic hot spot associated with AVS spatial and seasonal variation.

PubMed

Campana, O; Rodríguez, A; Blasco, J

2009-04-01

In risk assessment of aquatic sediments, much attention is paid to the difference between acid-volatile sulfide (AVS) and simultaneously extracted metals (SEMs) as indicators of metal availability. Ten representative sampling sites were selected along the estuary of the Guadalete River. Surficial sediments were sampled in winter and summer to better understand SEM and AVS spatial and seasonal distributions and to establish priority risk areas. Total SEM concentration (SigmaSEM) ranged from 0.3 to 4.7 micromol g(-1). It was not significantly different between seasons, however, it showed a significant difference between sampling stations. AVS concentrations were much more variable, showing significant spatial and temporal variations. The values ranged from 0.8 to 22.4 micromol g(-1). The SEM/AVS ratio was found to be <1 at all except one station located near the mouth of the estuary. The results provided information on a potential pollution source near the mouth of the estuary, probably associated with vessel-related activities carried out in a local harbor area located near the station.

Transport of suspended and bedload sediment at eight stations in the Coeur d'Alene River basin, Idaho

USGS Publications Warehouse

Clark, Greg M.; Woods, Paul F.

2000-01-01

At most of the stations, and at the stream discharges sampled, the bedload was primarily composed of material greater than 2 millimeters in diameter, the break between sand and gravel. A predominance of sand-sized bedload was noted at only a few stations, and generally only during low stream discharge. The particle-size distribution of bedload sediment at most stations became proportionately coarser as stream discharge increased. During the peak of snowmelt runoff for water years 1999 and 2000, gravel-sized material between 2 and 64 millimeters in diameter comprised more than 70 percent of the bedload transport at most stations. However, at the station on the Coeur d’Alene River at Rose Lake, the bedload was predominantly composed of fine-grained material of less than 1 millimeter in diameter for all measured stream discharges. The slow water velocities at Rose Lake accounted for the predominance of fine-grained sediment transport.

Distribution of the planktonic shrimp Lucifer (Thompson, 1829) (Decapoda, Sergestoidea) off the Amazon.

PubMed

Melo, N F A C; Neumann-Leitão, S; Gusmão, L M O; Martins-Neto, F E; Palheta, G D A

2014-08-01

Lucifer faxoni (BORRADAILE, 1915) and L. typus (EDWARDS, 1837) are species first identified in the neritic and oceanic waters off the Amazon. Samplings were made aboard the vessel "Antares" at 22 stations in July and August, 2001 with a bongo net (500-µm mesh size). Hydrological data were taken simultaneously for comparative purposes. L. faxoni was present at thirteen of the fourteen neritic stations analysed, as well as at five of the eight oceanic stations. L. typus was present at three of the fourteen neritic stations and in one of the eight oceanic stations. The highest density of L. faxoni in the neritic province was 7,000 ind.m(-3) (St. 82) and 159 ind.m(-3) (St. 75) in the oceanic area. For L. typus, the highest density observed was 41 ind.m(-3) (St. 64) in the neritic province. In the oceanic province, the highest single density value was recorded at station 75 (5 ind.m(-3)). Overall, L. faxoni typically presented the highest densities.

Preliminary study of the refaunation of alkaline shale coal surface mine spoil by soil arthropods

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cross, E.A.; Wilman, J.M.

1982-12-01

Soil sampling stations were laid out on (largely) untopsoiled shale surface mine spoil in 1979. Stations were located on spoil graded in 1978-1979, in ungraded spoil cast in 1972 and aerially seeded in 1973, and in adjacent off-mine woods and an old field. Additional stations were added in 1982 on spoil graded only 3.5 weeks - 3 months prior to sampling. Stations were located to include important variables typical of the mine. Of 17 classes-orders of arthropods recovered from all sites, only Acari (78-99% of total individuals) and Collembola (2-12%) were consistently widespread and numerous, and only Acari were importantmore » in the youngest spoils. A total of 69 mite families - superfamilies - were identified during the course of the study. Low-moderate mite populations were found in bare shale spoil graded only 3.5 weeks - 3 months prior to sampling, these distributed among 4 families. Samples from 1978-79 spoil contained 13 families 3-7 months after grading and 2 years later were comparable to off-mine sites both in numbers of individuals and number of families. Spoil from 1973 was comparable to off-mine sites in these 2 respects when first sampled. Earliest pioneer species were 3 (presumably) microherbivores, these remaining dominant for several years. Predatory mites appeared early and were well established less than a year after grading. Saprovores were absent or relatively scarce in the 2 youngest spoils, but well established in the 1973 spoil at first sampling.« less

Primary Dendrite Array Morphology: Observations from Ground-based and Space Station Processed Samples

NASA Technical Reports Server (NTRS)

Tewari, Surendra; Rajamure, Ravi; Grugel, Richard; Erdmann, Robert; Poirier, David

2012-01-01

Influence of natural convection on primary dendrite array morphology during directional solidification is being investigated under a collaborative European Space Agency-NASA joint research program, "Microstructure Formation in Castings of Technical Alloys under Diffusive and Magnetically Controlled Convective Conditions (MICAST)". Two Aluminum-7 wt pct Silicon alloy samples, MICAST6 and MICAST7, were directionally solidified in microgravity on the International Space Station. Terrestrially grown dendritic monocrystal cylindrical samples were remelted and directionally solidified at 18 K/cm (MICAST6) and 28 K/cm (MICAST7). Directional solidification involved a growth speed step increase (MICAST6-from 5 to 50 micron/s) and a speed decrease (MICAST7-from 20 to 10 micron/s). Distribution and morphology of primary dendrites is currently being characterized in these samples, and also in samples solidified on earth under nominally similar thermal gradients and growth speeds. Primary dendrite spacing and trunk diameter measurements from this investigation will be presented.

Primary Dendrite Array: Observations from Ground-Based and Space Station Processed Samples

NASA Technical Reports Server (NTRS)

Tewari, Surendra N.; Grugel, Richard N.; Erdman, Robert G.; Poirier, David R.

2012-01-01

Influence of natural convection on primary dendrite array morphology during directional solidification is being investigated under a collaborative European Space Agency-NASA joint research program, Microstructure Formation in Castings of Technical Alloys under Diffusive and Magnetically Controlled Convective Conditions (MICAST). Two Aluminum-7 wt pct Silicon alloy samples, MICAST6 and MICAST7, were directionally solidified in microgravity on the International Space Station. Terrestrially grown dendritic monocrystal cylindrical samples were remelted and directionally solidified at 18 K per centimeter (MICAST6) and 28 K per centimeter (MICAST7). Directional solidification involved a growth speed step increase (MICAST6-from 5 to 50 millimeters per second) and a speed decrease (MICAST7-from 20 to 10 millimeters per second). Distribution and morphology of primary dendrites is currently being characterized in these samples, and also in samples solidified on earth under nominally similar thermal gradients and growth speeds. Primary dendrite spacing and trunk diameter measurements from this investigation will be presented.

Rupture process of the September 12, 2007 Southern Sumatra earthquake from tsunami waveform inversion

NASA Astrophysics Data System (ADS)

Lorito, S.; Romano, F.; Piatanesi, A.

2007-12-01

The aim of this work is to infer the slip distribution and mean rupture velocity along the rupture zone of the 12 September 2007 Southern Sumatra, Indonesia from available tide-gauge records of the tsunami. We select waveforms from 12 stations, distributed along the west coast of Sumatra and in the whole Indian Ocean (11 GLOSS stations and 1 DART buoy). We assume the fault plane and the slip direction to be consistent with both the geometry of the subducting plate and the early focal mechanism solutions. Then we subdivide the fault plane into several subfaults (both along strike and down dip) and compute the corresponding Green's functions by numerical solution of the shallow water equations through a finite difference method. The slip distribution and rupture velocity are determined simultaneously by means of a simulated annealing technique. We compare the recorded and synthetic waveforms in the time domain, using a cost function that is a trade-off between the L1 and L2 norms. Preliminary synthetic checkerboard tests, using the station coverage and the sampling interval of the available data, indicate that the main features of the rupture process may be robustly inverted.

Composition, abundance and distribution of macrozooplankton in Culebra Bay, Gulf of Papagayo, Pacific coast of Costa Rica and its value as bioindicator of pollution.

PubMed

Bednarski, Melinda; Morales-Ramírez, Alvaro

2004-12-01

The abundance, distribution and composition of the macrozooplankton of Culebra Bay, Costa Rica (10 degrees 38' N - 85 degrees 40' W) were studied at four stations throughout the dry (February-May) and rainy (September-November) seasons of 2000. The samples were collected at two-week intervals using a 500 microm mesh net with a 0.5 m diameter opening. Copepods (23-31%) and ostracods (20-34%) were predominant throughout the year, followed by cladocerans (2.5-14%), zoea (6.6-9.5%), and siphonophores (2.5-7.2%). High densities of zooplankton were obtained in February and March with peak abundance on March 18. The lowest densities were observed on September 3 and November 5. Significant differences in abundances at each station were observed for the groups Acartia tonsa (Copepoda), Ctenophora, Medusae, Ostracoda, Zoea, and Amphipoda. Comparison of the dry and rainy seasons revealed significantly higher zooplankton abundance in the dry season and copepod domination of all stations; during the rainy season ostracods dominated the off-shore areas. Zooplankton abundance and distribution are influenced by upwelling, which occurs during the dry season in Culebra Bay.

Impact of climate variability on ichthyoplankton communities: An example of a small temperate estuary

NASA Astrophysics Data System (ADS)

Primo, Ana Lígia; Azeiteiro, Ulisses Miranda; Marques, Sónia Cotrim; Pardal, Miguel Ângelo

2011-03-01

Recent variations in the precipitation regime across southern Europe have led to changes in river fluxes and salinity gradients affecting biological communities in most rivers and estuaries. A sampling programme was developed in the Mondego estuary, Portugal, from January 2003 to December 2008 at five distinct sampling stations to evaluate spatial, seasonal and inter-annual distributions of fish larvae. Gobiidae was the most abundant family representing 80% of total catch and Pomatoschistus spp. was the most important taxon. The fish larval community presented a clear seasonality with higher abundances and diversities during spring and summer seasons. Multivariate analysis reinforced differences among seasons but not between years or sampling stations. The taxa Atherina presbyter, Solea solea, Syngnathus abaster, Crystallogobius linearis and Platichthys flesus were more abundant during spring/summer period while Ammodytes tobianus, Callionymus sp., Echiichthys vipera and Liza ramada were more abundant in autumn/winter. Temperature, chlorophyll a and river flow were the main variation drivers observed although extreme drought events (year 2005) seemed not to affect ichthyoplankton community structure. Main changes were related to a spatial displacement of salinity gradient along the estuarine system which produced changes in marine species distribution.

American Samoa's forest resources, 2001.

Treesearch

Joseph A. Donnegan; Sheri S. Mann; Sarah L. Butler; Bruce A. Hiserote

2004-01-01

The Forest Inventory and Analysis Program of the Pacific Northwest Research Station collected, analyzed, and summarized data from field plots, and mapped land cover on four islands in American Samoa. This statistical sample provides estimates of forest area, stem volume, biomass, numbers of trees, damages to trees, and tree size distribution. The summary provides...

Mississippi Sound remote sensing study. [NASA Earth Resources Laboratory seasonal experiments

NASA Technical Reports Server (NTRS)

Atwell, B. H.; Thomann, G. C.

1973-01-01

A study of the Mississippi Sound was initiated in early 1971 by personnel of NASA Earth Resources Laboratory. Four separate seasonal experiments consisting of quasi-synoptic remote and surface measurements over the entire area were planned. Approximately 80 stations distributed throughout Mississippi Sound were occupied. Surface water temperature and secchi extinction depth were measured at each station and water samples were collected for water quality analyses. The surface distribution of three water parameters of interest from a remote sensing standpoint - temperature, salinity and chlorophyll content - are displayed in map form. Areal variations in these parameters are related to tides and winds. A brief discussion of the general problem of radiative measurements of water temperature is followed by a comparison of remotely measured temperatures (PRT-5) to surface vessel measurements.

Customer exposure to MTBE, TAME, C6 alkyl methyl ethers, and benzene during gasoline refueling.

PubMed

Vainiotalo, S; Peltonen, Y; Ruonakangas, A; Pfäffli, P

1999-02-01

We studied customer exposure during refueling by collecting air samples from customers' breathing zone. The measurements were carried out during 4 days in summer 1996 at two Finnish self-service gasoline stations with "stage I" vapor recovery systems. The 95-RON (research octane number) gasoline contained approximately 2.7% methyl tert-butyl ether (MTBE), approximately 8.5% tert-amyl methyl ether (TAME), approximately 3.2% C6 alkyl methyl ethers (C6 AMEs), and 0.75% benzene. The individual exposure concentrations showed a wide log-normal distribution, with low exposures being the most frequent. In over 90% of the samples, the concentration of MTBE was higher (range <0.02-51 mg/m3) than that of TAME. The MTBE values were well below the short-term (15 min) threshold limits set for occupational exposure (250-360 mg/m3). At station A, the geometric mean concentrations in individual samples were 3.9 mg/m3 MTBE and 2. 2 mg/m3 TAME. The corresponding values at station B were 2.4 and 1.7 mg/m3, respectively. The average refueling (sampling) time was 63 sec at station A and 74 sec at station B. No statistically significant difference was observed in customer exposures between the two service stations. The overall geometric means (n = 167) for an adjusted 1-min refueling time were 3.3 mg/m3 MTBE and 1.9 mg/m3 TAME. Each day an integrated breathing zone sample was also collected, corresponding to an arithmetic mean of 20-21 refuelings. The overall arithmetic mean concentrations in the integrated samples (n = 8) were 0.90 mg/m3 for benzene and 0.56 mg/m3 for C6 AMEs calculated as a group. Mean MTBE concentrations in ambient air (a stationary point in the middle of the pump island) were 0.16 mg/m3 for station A and 0.07 mg/m3 for station B. The mean ambient concentrations of TAME, C6 AMEs, and benzene were 0.031 mg/m3, approximately 0.005 mg/m3, and approximately 0.01 mg/m3, respectively, at both stations. The mean wind speed was 1.4 m/sec and mean air temperature was 21 degreesC. Of the gasoline refueled during the study, 75% was 95 grade and 25% was 98/99 grade, with an oxygenate (MTBE) content of 12.2%.

Customer exposure to MTBE, TAME, C6 alkyl methyl ethers, and benzene during gasoline refueling.

PubMed Central

Vainiotalo, S; Peltonen, Y; Ruonakangas, A; Pfäffli, P

1999-01-01

We studied customer exposure during refueling by collecting air samples from customers' breathing zone. The measurements were carried out during 4 days in summer 1996 at two Finnish self-service gasoline stations with "stage I" vapor recovery systems. The 95-RON (research octane number) gasoline contained approximately 2.7% methyl tert-butyl ether (MTBE), approximately 8.5% tert-amyl methyl ether (TAME), approximately 3.2% C6 alkyl methyl ethers (C6 AMEs), and 0.75% benzene. The individual exposure concentrations showed a wide log-normal distribution, with low exposures being the most frequent. In over 90% of the samples, the concentration of MTBE was higher (range <0.02-51 mg/m3) than that of TAME. The MTBE values were well below the short-term (15 min) threshold limits set for occupational exposure (250-360 mg/m3). At station A, the geometric mean concentrations in individual samples were 3.9 mg/m3 MTBE and 2. 2 mg/m3 TAME. The corresponding values at station B were 2.4 and 1.7 mg/m3, respectively. The average refueling (sampling) time was 63 sec at station A and 74 sec at station B. No statistically significant difference was observed in customer exposures between the two service stations. The overall geometric means (n = 167) for an adjusted 1-min refueling time were 3.3 mg/m3 MTBE and 1.9 mg/m3 TAME. Each day an integrated breathing zone sample was also collected, corresponding to an arithmetic mean of 20-21 refuelings. The overall arithmetic mean concentrations in the integrated samples (n = 8) were 0.90 mg/m3 for benzene and 0.56 mg/m3 for C6 AMEs calculated as a group. Mean MTBE concentrations in ambient air (a stationary point in the middle of the pump island) were 0.16 mg/m3 for station A and 0.07 mg/m3 for station B. The mean ambient concentrations of TAME, C6 AMEs, and benzene were 0.031 mg/m3, approximately 0.005 mg/m3, and approximately 0.01 mg/m3, respectively, at both stations. The mean wind speed was 1.4 m/sec and mean air temperature was 21 degreesC. Of the gasoline refueled during the study, 75% was 95 grade and 25% was 98/99 grade, with an oxygenate (MTBE) content of 12.2%. Images Figure 1 Figure 2 Figure 3 Figure 4 PMID:9924009

Effects of Geostrophic Kinetic Energy on the Distribution of Mesopelagic Fish Larvae in the Southern Gulf of California in Summer/Fall Stratified Seasons.

PubMed

Contreras-Catala, Fernando; Sánchez-Velasco, Laura; Beier, Emilio; Godínez, Victor M; Barton, Eric D; Santamaría-Del-Angel, Eduardo

2016-01-01

Effects of geostrophic kinetic energy flux on the three-dimensional distribution of fish larvae of mesopelagic species (Vinciguerria lucetia, Diogenichthys laternatus, Benthosema panamense and Triphoturus mexicanus) in the southern Gulf of California during summer and fall seasons of stronger stratification were analyzed. The greatest larval abundance was found at sampling stations in geostrophic kinetic energy-poor areas (<7.5 J/m3), where the distribution of the dominant species tended to be stratified. Larvae of V. lucetia (average abundance of 318 larvae/10m2) and B. panamense (174 larvae/10m2) were mostly located in and above the pycnocline (typically ~ 40 m depth). In contrast, larvae of D. laternatus (60 larvae/10m2) were mainly located in and below the pycnocline. On the other hand, in sampling stations from geostrophic kinetic energy-rich areas (> 21 J/m3), where mesoscale eddies were present, the larvae of the dominant species had low abundance and were spread more evenly through the water column, in spite of the water column stratification. For example, in a cyclonic eddy, V. lucetia larvae (34 larvae/10m2) extended their distribution to, at least, the limit of sampling 200 m depth below the pycnocline, while D. laternatus larvae (29 larvae/10m2) were found right up to the surface, both probably as a consequence mixing and secondary circulation in the eddy. Results showed that the level of the geostrophic kinetic energy flux affects the abundance and the three-dimensional distribution of mesopelagic fish larvae during the seasons of stronger stratification, indicating that areas with low geostrophic kinetic energy may be advantageous for feeding and development of mesopelagic fish larvae because of greater water column stability.

Effects of Geostrophic Kinetic Energy on the Distribution of Mesopelagic Fish Larvae in the Southern Gulf of California in Summer/Fall Stratified Seasons

PubMed Central

Contreras-Catala, Fernando; Beier, Emilio; Godínez, Victor M.; Barton, Eric D.; Santamaría-del-Angel, Eduardo

2016-01-01

Effects of geostrophic kinetic energy flux on the three-dimensional distribution of fish larvae of mesopelagic species (Vinciguerria lucetia, Diogenichthys laternatus, Benthosema panamense and Triphoturus mexicanus) in the southern Gulf of California during summer and fall seasons of stronger stratification were analyzed. The greatest larval abundance was found at sampling stations in geostrophic kinetic energy-poor areas (<7.5 J/m3), where the distribution of the dominant species tended to be stratified. Larvae of V. lucetia (average abundance of 318 larvae/10m2) and B. panamense (174 larvae/10m2) were mostly located in and above the pycnocline (typically ~ 40 m depth). In contrast, larvae of D. laternatus (60 larvae/10m2) were mainly located in and below the pycnocline. On the other hand, in sampling stations from geostrophic kinetic energy-rich areas (> 21 J/m3), where mesoscale eddies were present, the larvae of the dominant species had low abundance and were spread more evenly through the water column, in spite of the water column stratification. For example, in a cyclonic eddy, V. lucetia larvae (34 larvae/10m2) extended their distribution to, at least, the limit of sampling 200 m depth below the pycnocline, while D. laternatus larvae (29 larvae/10m2) were found right up to the surface, both probably as a consequence mixing and secondary circulation in the eddy. Results showed that the level of the geostrophic kinetic energy flux affects the abundance and the three-dimensional distribution of mesopelagic fish larvae during the seasons of stronger stratification, indicating that areas with low geostrophic kinetic energy may be advantageous for feeding and development of mesopelagic fish larvae because of greater water column stability. PMID:27760185

Graphical correlation of gaging-station records

USGS Publications Warehouse

Searcy, James K.

1960-01-01

A gaging-station record is a sample of the rate of flow of a stream at a given site. This sample can be used to estimate the magnitude and distribution of future flows if the record is long enough to be representative of the long-term flow of the stream. The reliability of a short-term record for estimating future flow characteristics can be improved through correlation with a long-term record. Correlation can be either numerical or graphical, but graphical correlation of gaging-station records has several advantages. The graphical correlation method is described in a step-by-step procedure with an illustrative problem of simple correlation, illustrative problems of three examples of multiple correlation--removing seasonal effect--and two examples of correlation of one record with two other records. Except in the problem on removal of seasonal effect, the same group of stations is used in the illustrative problems. The purpose of the problems is to illustrate the method--not to show the improvement that can result from multiple correlation as compared with simple correlation. Hydrologic factors determine whether a usable relation exists between gaging-station records. Statistics is only a tool for evaluating and using an existing relation, and the investigator must be guided by a knowledge of hydrology.

Cost comparison of competing local distribution systems for communication satellite traffic

NASA Technical Reports Server (NTRS)

Dopfel, F. E.

1979-01-01

The boundaries of market areas which favor various means for distributing communications satellite traffic are considered. The distribution methods considered are: control Earth station with cable access, rooftop Earth stations, Earth station with radio access, and various combinations of these methods. The least cost system for a hypothetical region described by number of users and the average cable access mileage is discussed. The region is characterized by a function which expresses the distribution of users. The results indicate that the least cost distribution is central Earth station with cable access for medium to high density areas of a region combined with rooftop Earth stations or (for higher volumes) radio access for remote users.

Locations of Sampling Stations for Water Quality Monitoring in Water Distribution Networks.

PubMed

Rathi, Shweta; Gupta, Rajesh

2014-04-01

Water quality is required to be monitored in the water distribution networks (WDNs) at salient locations to assure the safe quality of water supplied to the consumers. Such monitoring stations (MSs) provide warning against any accidental contaminations. Various objectives like demand coverage, time for detection, volume of water contaminated before detection, extent of contamination, expected population affected prior to detection, detection likelihood and others, have been independently or jointly considered in determining optimal number and location of MSs in WDNs. "Demand coverage" defined as the percentage of network demand monitored by a particular monitoring station is a simple measure to locate MSs. Several methods based on formulation of coverage matrix using pre-specified coverage criteria and optimization have been suggested. Coverage criteria is defined as some minimum percentage of total flow received at the monitoring stations that passed through any upstream node included then as covered node of the monitoring station. Number of monitoring stations increases with the increase in the value of coverage criteria. Thus, the design of monitoring station becomes subjective. A simple methodology is proposed herein which priority wise iteratively selects MSs to achieve targeted demand coverage. The proposed methodology provided the same number and location of MSs for illustrative network as an optimization method did. Further, the proposed method is simple and avoids subjectivity that could arise from the consideration of coverage criteria. The application of methodology is also shown on a WDN of Dharampeth zone (Nagpur city WDN in Maharashtra, India) having 285 nodes and 367 pipes.

Groundwater quality and occurrence and distribution of selected constituents in the Aquia and Upper Patapsco aquifers, Naval Air Station Patuxent River, St. Mary's County, Maryland, July 2008

USGS Publications Warehouse

Dieter, Cheryl A.; Campo, Kimberly W.; Baker, Anna C.

2012-01-01

The Naval Air Station Patuxent River in southern Maryland has continued to expand in the first decade of the 21st century, contributing to rapid population growth in the surrounding area. The increase in population has caused State and County water managers and others to be concerned about the impact of population growth on the quantity and quality of groundwater supplies. The U.S. Geological Survey has been investigating the groundwater resources of the air station since 1998. As part of that ongoing investigation, groundwater was sampled in 2008 in six wells in the Aquia aquifer and two wells in the Upper Patapsco aquifer in the vicinity of Naval Air Station Patuxent River and Webster Outlying Field. Groundwater samples were analyzed for basic chemistry (field parameters, major ions, and nutrients) as well as several water-quality issues of concern including the occurrence of arsenic and tungsten, and saltwater intrusion. The results of the 2008 groundwater-quality sampling indicate that the overall quality of groundwater in the Aquia aquifer has not changed since 1943; data are too limited to determine if groundwater quality has changed in the Upper Patapsco aquifer. At one well in the Aquia aquifer, the arsenic concentration exceeded the U.S. Environmental Protection Agency standard for drinking water. Arsenic was not detected in samples from the Upper Patapsco aquifer. Tungsten concentrations were detected at low concentrations near the laboratory reporting level in all eight samples. There was no evidence of saltwater intrusion in any of the wells.

Physically based method for measuring suspended-sediment concentration and grain size using multi-frequency arrays of acoustic-doppler profilers

USGS Publications Warehouse

Topping, David J.; Wright, Scott A.; Griffiths, Ronald; Dean, David

2014-01-01

As the result of a 12-year program of sediment-transport research and field testing on the Colorado River (6 stations in UT and AZ), Yampa River (2 stations in CO), Little Snake River (1 station in CO), Green River (1 station in CO and 2 stations in UT), and Rio Grande (2 stations in TX), we have developed a physically based method for measuring suspended-sediment concentration and grain size at 15-minute intervals using multifrequency arrays of acoustic-Doppler profilers. This multi-frequency method is able to achieve much higher accuracies than single-frequency acoustic methods because it allows removal of the influence of changes in grain size on acoustic backscatter. The method proceeds as follows. (1) Acoustic attenuation at each frequency is related to the concentration of silt and clay with a known grain-size distribution in a river cross section using physical samples and theory. (2) The combination of acoustic backscatter and attenuation at each frequency is uniquely related to the concentration of sand (with a known reference grain-size distribution) and the concentration of silt and clay (with a known reference grain-size distribution) in a river cross section using physical samples and theory. (3) Comparison of the suspended-sand concentrations measured at each frequency using this approach then allows theory-based calculation of the median grain size of the suspended sand and final correction of the suspended-sand concentration to compensate for the influence of changing grain size on backscatter. Although this method of measuring suspended-sediment concentration is somewhat less accurate than using conventional samplers in either the EDI or EWI methods, it is much more accurate than estimating suspended-sediment concentrations using calibrated pump measurements or single-frequency acoustics. Though the EDI and EWI methods provide the most accurate measurements of suspended-sediment concentration, these measurements are labor-intensive, expensive, and may be impossible to collect at time intervals less than discharge-independent changes in suspended-sediment concentration can occur (< hours). Therefore, our physically based multi-frequency acoustic method shows promise as a cost-effective, valid approach for calculating suspended-sediment loads in river at a level of accuracy sufficient for many scientific and management purposes.

Characteristics of Recreationists in Northeastern New Mexico. Agricultural Experiment Station Research Report 209.

ERIC Educational Resources Information Center

Gray, James R.; Blair, Thomas J.

This report investigated the characteristics of summertime recreationists in northeastern New Mexico. A description of the area was given including the physical and economic characteristics. Data were gathered through a modified random sampling procedure. A prepared questionnaire was distributed to recreationists at 13 sites in New Mexico. The…

Biodiversity of benthic macroinvertebrates in Air Terjun Asahan, Asahan, Melaka, Malaysia

NASA Astrophysics Data System (ADS)

Nurhafizah-Azwa, S.; Ahmad A., K.

2016-11-01

A study on benthic macroinvertebrate diversity was conducted at Air Terjun Asahan, Asahan, Melaka. Five stations were selected with distance intervals of approximately 500 metres. Three replicates of benthic macroinvertebrate and water samples were taken. Results classified Air Terjun Asahan in class II, which indicated good water quality based on WQI recommended by the Department of Environment. A total of 1 phylum, 2 classes, 6 order, 30 families, and 2183 individuals were successfully sampled and recorded. The analysis showed that the average value of Shannon Diversity Index, H' (2.19), Pielou Evenness Index, J' (0.30), and Margaleff Richness Index, DMG (3.77) described that Air Terjun Asahan was in moderate condition and the distribution of macroinvertebrates was uniform between stations. Correlation test showed that the WQI had a strong relationship with the diversity indices involved. BMWP, and FBI showed that Air Terjun Asahan was in good water quality. CCA test was conducted to show environmental factors towards benthic macroinvertebrate distribution. The presence of Leptophlebiidae, Baetidae, Heptageniidae and Chironomidae with high abundance of the families showed the potential as biological indicators of a clean ecosystem.

Particulate Trace Element Cycling in a Diatom Bloom at Station ALOHA

NASA Astrophysics Data System (ADS)

Weisend, R.; Morton, P. L.; Landing, W. M.; Fitzsimmons, J. N.; Hayes, C. T.; Boyle, E. A.

2014-12-01

Phytoplankton in oligotrophic marine deserts depend on remote sources to supply trace nutrients. To examine these sources, marine particulate matter samples from the central North Pacific (Station ALOHA) were collected during the July-August 2012 HOE-DYLAN cruises and analyzed for a suite of trace (e.g., Fe, Mn) and major (e.g. Al, P) elements. Daily surface SPM samples were examined for evidence of atmospheric deposition and biological uptake, while five vertical profiles were examined for evidence of surface vertical export and subsurface horizontal transport from nearby sources (e.g., margin sediments, hydrothermal plumes). Maxima in surface particulate P (a biological tracer) corresponded with a diatom bloom, and surprisingly also coincided with maxima in particulate Al (typically a tracer for lithogenic inputs). The surface particulate Al distributions likely result from the adsorption of dissolved Al onto diatom silica frustules, not from atmospheric dust deposition. In addition, a subsurface maximum in particulate Al and P was observed four days later at 75m, possibly resulting from vertical export of the surface diatom bloom. The distributions of other bioactive trace elements (e.g. Cd, Co, Cu) will be presented in the context of the diatom bloom and other biological, chemical and physical features. A second, complementary poster is also being presented which examines the cycling of trace elements in lithogenic particles (Morton et al., "Trace Element Cycling in Lithogenic Particles at Station ALOHA").

The structure of fungal biomass and diversity of cultivated micromycetes in Antarctic soils (progress and Russkaya Stations)

NASA Astrophysics Data System (ADS)

Marfenina, O. E.; Nikitin, D. A.; Ivanova, A. E.

2016-08-01

The distribution of the fungal biomass and diversity of cultivated microscopic fungi in the profiles of some soils from East (Progress Station, valleys of the Larsemann Hills oasis) and West (Russkaya Station, the Marie Byrd Land) Antarctica regions were studied. The structure of the biomass (spore/mycelium and live cells/dead cells) was analyzed by fluorescence microscopy with staining using a set of coloring agents: calcofluor white, ethidium bromide, and fluorescein diacetate. The species composition of the cultivated microscopic fungi was determined on Czapek's medium. The fungal biomass in the soils studied is not high (on the average, 0.3 mg/g of soil); the greatest biomass (0.6 mg/g) was found in the soil samples with plant residues. The fungal biomass is mainly (to 70%) represented by small (to 2.5 μm) spores. About half of the fungal biomass is composed of living cells. There are differences in the distribution of the fungal biomass within the profiles of different primitive soils. In the soil samples taken under mosses and lichens, the maximal biomass was registered in the top soil horizons. In the soils with the peat horizon under stone pavements, the greatest fungal biomass was registered in the subsurface horizons. Thirty-eight species of cultivated microscopic fungi were isolated from the soils studied. Species of the genus Penicillium and Phoma herbarum predominated.

Distribution and pollution assessment of heavy metals in surface sediments in Xiaoqing river estuary and its adjacent sea of Laizhou bay

NASA Astrophysics Data System (ADS)

Wang, Li; Luo, Xianxiang; Fan, Yuqing

2018-03-01

In this paper, the monitoring results of four heavy metals Cu, Pb, Zn and Hg at 10 sampling stations in Xiaoqing river estuary and its adjacent sea of Laizhou Bay in November 2008 were analyzed and evaluated. The results showed that the concentrations of heavy metals in the steam channel and estuary are higher than those in the adjacent sea, and the metal concentrations were below the standard for I class of marine sediment quality, excepting the station 2 in the steam channel and station 5 in the estuary. The assessment of the single-factor pollution index showed that the overall pollution level of the study area was relatively low, but there was serious pollution phenomenon in individual station. The potential ecological risk of heavy metals in the surface sediments was generally at a low level, and Hg had the highest potential risk.

The distribution of ichthyoplankton in thermal and non-thermal creeks and swamps on the Savannah River Plant, February-July 1985

DOE Office of Scientific and Technical Information (OSTI.GOV)

Paller, M.H.; Saul, B.M.; Hughes, D.W.

1986-01-01

The report deals with the distribution of ichthyoplankton in the Savannah River tributary streams and associated swamps located on the SRP during the 1985 spawning season (February-July). The 1985 sampling program was a continuation of the 1984 program and, except for the addition of seven sampling stations and minor methodological changes, incorporated the same sampling sites and procedures. The streams under study were Upper Three Runs Creek, Beaver Dam Creek, Four Mile Creek, Pen Branch, Steel Creek, Meyer's Branch and Lower Three Runs Creek. The objectives were to determine: (1) the density, distribution and species composition of ichthyoplankton at samplemore » sites in the creeks and swamps of the SRP; (2) how ichthyoplankton in SRP creeks and swamps is distributed in relation to habitat and temperature; (3) the effects of elevated temperatures on ichthyoplankton distribution and abundance and on the time of spawning; and (4) the magnitude of yearly variations in ichthyoplankton abundance in the creeks and swamps of the SRP and the reasons for these variations.« less

DNA Barcoding of Zooplankton in the Hampton Roads Area: A Biodiversity Assessment

NASA Astrophysics Data System (ADS)

Salcedo, A.; Rodríguez, Á. E.; Gibson, D. M.

2016-02-01

The study of zooplankton biodiversity and distribution is crucial to understand oceanic ecosystems and anticipate the effects of climate change. Previously, identification of zooplankton relied in morphological identification employed by expert taxonomists. DNA barcoding, a technique that uses the mitochondrial DNA (mtDNA) Cytochrome Oxidase 1 (CO1) gene is widely used for taxonomic identification. Thus, this molecular technique will be used to begin a detailed characterization of zooplankton diversity, abundance and community structure in the Hampton Roads Area (HRA). Stations 1 (Jones Creek) and 3 (lower Chesapeake Bay) were sampled in June 19, 2015. Stations 1, 2 (James River), and 3 were sampled in September 2015. Zooplankton samples were collected in triplicates with a 0.5m, 200 µm mesh net. Physical parameters (dissolved oxygen, salinity, temperature and, water transparency) were measured. Species identified as Opistonema oglinum (Atlantic Thread Herring) and Paracalanus parvus copepods were found at station 3; Anchoa mitchilli and Acartia tonsa copepods were found at stations 1 and 3. This study indicates that mtDNA-CO1 barcoding is suitable to identify zooplankton to the species level and helps validate DNA barcoding as a faster, more accurate taxonomic approach. The long term objective of this project is to provide a comprehensive assessment of zooplankton in the HRA and to generate a reference record for broad monitoring programs; vital for a better understanding and management of ecologically and commercially important species.

Survival of pathogenic bacteria under nutrient starvation conditions. [aboard orbiting space stations

NASA Technical Reports Server (NTRS)

Boyle, Michael; Ford, Tim; Mitchell, Ralph; Maki, James

1990-01-01

The survival of opportunistic pathogenic microorganisms in water, under nutrient-limiting conditions, has been investigated in order to ascertain whether human pathogens can survive within a water-distribution system of the kind proposed for the NASA Space Station. Cultures of a strain of pseudomonas aeruginosa and two strains of staphylococcus aureus were incubated at 10, 25, or 37 C, and samples at 1 day, 1 week, 1 month, and six weeks. While neither of the staphylococcus strains tested were detected after 1 week of starvation, the pseudomonas strain can survive in deionized water at all three temperatures.

[Effects of macro-jellyfish abundance dynamics on fishery resource structure in the Yangtze River estuary and its adjacent waters].

PubMed

Shan, Xiu-Juan; Zhuang, Zhi-Meng; Jin, Xian-Shi; Dai, Fang-Qun

2011-12-01

Based on the bottom trawl survey data in May 2007 and May and June 2008, this paper analyzed the effects of the abundance dynamics of macro-jellyfish on the species composition, distribution, and abundance of fishery resource in the Yangtze River estuary and its adjacent waters. From May 2007 to June 2008, the average catch per haul and the top catch per haul of macro-jellyfish increased, up to 222.2 kg x h(-1) and 1800 kg x h(-1) in June 2008, respectively. The macro-jellyfish were mainly distributed in the areas around 50 m isobath, and not beyond 100 m isobath where was the joint front of the coastal waters of East China Sea, Yangtze River runoff, and Taiwan Warm Current. The main distribution area of macro-jellyfish in June migrated northward, as compared with that in May, and the highest catches of macro-jellyfish in May 2007 and May 2008 were found in the same sampling station (122.5 degrees E, 28.5 degrees N). In the sampling stations with higher abundance of macro-jellyfish, the fishery abundance was low, and the fishery species also changed greatly, mainly composed by small-sized species (Trachurus japonicus, Harpadon nehereus, and Acropoma japonicum) and pelagic species (Psenopsis anomala, Octopus variabilis) and Trichiurus japonicus, and P. anomala accounted for 23.7% of the total catch in June 2008. Larimichthys polyactis also occupied higher proportion of the total catch in sampling stations with higher macro-jellyfish abundance, but the demersal species Lophius litulon was not found, and a few crustaceans were collected. This study showed that macro-jellyfish had definite negative effects on the fishery community structure and abundance in the Yangtze River estuary fishery ecosystem, and further, changed the energy flow patterns of the ecosystem through cascading trophic interactions. Therefore, macro-jellyfish was strongly suggested to be an independent ecological group when the corresponding fishery management measures were considered.

Bacterial Diversity and Nitrogen Utilization Strategies in the Upper Layer of the Northwestern Pacific Ocean.

PubMed

Li, Yuan-Yuan; Chen, Xiao-Huang; Xie, Zhang-Xian; Li, Dong-Xu; Wu, Peng-Fei; Kong, Ling-Fen; Lin, Lin; Kao, Shuh-Ji; Wang, Da-Zhi

2018-01-01

Nitrogen (N) is a primary limiting nutrient for bacterial growth and productivity in the ocean. To better understand bacterial community and their N utilization strategy in different N regimes of the ocean, we examined bacterial diversity, diazotrophic diversity, and N utilization gene expressions in the northwestern Pacific Ocean (NWPO) using a combination of high-throughput sequencing and real-time qPCR methods. 521 and 204 different operational taxonomic units (OTUs) were identified in the 16s rRNA and nifH libraries from nine surface samples. Of the 16s rRNA gene OTUs, 11.9% were observed in all samples while 3.5 and 15.9% were detected only in N-sufficient and N-deficient samples. Proteobacteria, Cyanobacteria and Bacteroidetes dominated the bacterial community. Prochlorococcus and Pseudoalteromonas were the most abundant at the genus level in N-deficient regimes, while SAR86, Synechococcus and SAR92 were predominant in the Kuroshio-Oyashio confluence region. The distribution of the nifH gene presented great divergence among sampling stations: Cyanobacterium_UCYN-A dominated the N-deficient stations, while clusters related to the Alpha-, Beta- , and Gamma-Proteobacteria were abundant in other stations. Temperature was the main factor that determined bacterial community structure and diversity while concentration of NO X -N was significantly correlated with structure and distribution of N 2 -fixing microorganisms. Expression of the ammonium transporter was much higher than that of urea transporter subunit A ( urtA ) and ferredoxin-nitrate reductase , while urtA had an increased expression in N-deficient surface water. The predicted ammonium transporter and ammonium assimilation enzymes were most abundant in surface samples while urease and nitrogenase were more abundant in the N-deficient regions. These findings underscore the fact that marine bacteria have evolved diverse N utilization strategies to adapt to different N habitats, and that urea metabolism is of vital ecological importance in N-deficient regimes.

Ecological risk assessment of elemental pollution in sediment from Tunku Abdul Rahman National Park, Sabah

DOE Office of Scientific and Technical Information (OSTI.GOV)

Elias, Md Suhaimi; Hamzah, Mohd Suhaimi; Rahman, Shamsiah Ab

Eleven (11) surface sediment samples were collected from Tunku Abdul Rahman National Park, Sabah. The neutron activation analysis (NAA) and inductively coupled plasma-mass spectrometry (ICP-MS) techniques were applied for the determinations metal contents and their distributions in sediment samples. The results shown that Arsenic (As) concentrations are enriched at all sampling stations except for station TAR 09, with enrichment factor (EF) values ranged from 1.1 to 7.2. The elements such as Cd, Cr, Sb and U showed enrichment at a few stations and other elements (Cr, Cu, Pb, Th, Zn) shown as background levels in all stations. Degrees of contaminationmore » in this study were calculated base on concentrations of six elements (As, Cd, Cr, Cu, Pb, and Zn). TAR 11 station can be categorized as very high degree of contamination with degree of contamination value of 43.2. TAR 07 station can be categorized as a considerable degree of contamination (contamination value of 16.9). Six stations (TAR 01, 03, 04, 05, 06, 08, 10) showed moderate degree of contamination, with contamination values ranging from 8.0 to 16.0. TAR 02 and TAR 09 stations showed low degree of contaminations (< 8.0). TAR 11 showed very high ecological risk index (R{sub I}) with RI value is 916. TAR 07 and TAR 10 showed moderate ecological risk index with R{sub I} value 263 and 213, respectively. Other stations showed low ecological risk with RI values ranging from 42.3 to 117 (< 150). Very high ecological risk index could give an adverse effect to the benthic organism. The data obtained from the enrichment factor, degree of contamination and ecological risk index provided vital information, which can be used for future comparison. Information from the present study will be useful to the relevant government agencies and authorities in preparing preventive action to control direct discharge of heavy metals from industries, agro-base activities and domestic waste to the rivers and the sea.« less

Microplastic pollution in the surface waters of the Bohai Sea, China.

PubMed

Zhang, Weiwei; Zhang, Shoufeng; Wang, Juying; Wang, Yan; Mu, Jingli; Wang, Ping; Lin, Xinzhen; Ma, Deyi

2017-12-01

The ubiquitous presence and persistency of microplastics in aquatic environments is of particular concern because these pollutants represent an increasing threat to marine organisms and ecosystems. An identification of the patterns of microplastic distribution will help to understand the scale of their potential effect on the environment and on organisms. In this study, the occurrence and distribution of microplastics in the Bohai Sea are reported for the first time. We sampled floating microplastics at 11 stations in the Bohai Sea using a 330 μm trawling net in August 2016. The abundance, composition, size, shape and color of collected debris samples were analyzed after pretreatment. The average microplastic concentration was 0.33 ± 0.34 particles/m 3 . Micro-Fourier transform infrared spectroscopy analysis showed that the main types of microplastics were polyethylene, polypropylene, and polystyrene. As the size of the plastics decreased, the percentage of polypropylene increased, whereas the percentages of polyethylene and polystyrene decreased. Plastic fragments, lines, and films accounted for most of the collected samples. Accumulation at some stations could be associated with transport and retention mechanisms that are linked to wind and the dynamics of the rim current, as well as different sources of the plastics. Copyright © 2017 Elsevier Ltd. All rights reserved.

Detection and distribution of Tris(2-chloroethyl) phosphate on the East Antarctic ice sheet.

PubMed

Cheng, Wenhan; Sun, Liguang; Huang, Wen; Ruan, Ting; Xie, Zhouqing; Zhang, Pengfei; Ding, Rui; Li, Ming

2013-08-01

Use of PBDEs (Polybrominated Diphenyl Ethers) has been restricted in Europe and North America in recent years. As substitute products with similar properties, OPEs (Organophosphate Esters) are now used as alternatives to PBDEs. Recent research has revealed that, similar to PBDEs, OPEs are also environmentally hazardous like PBDEs. Thus knowledge of their distribution and transport is needed to understand the extent of risk. However, studies on environmental OPEs mainly focus on Europe and North America. Knowledge in the southern hemisphere is very limited. In this study, we analyzed fresh snow samples collected along the transect from Zhongshan Station to Kunlun Station, East Antarctica. Several OPEs were detected in this transect, among which Tris(2-chloroethyl) phosphate (TCEP) had the highest frequency of quantification. It was quantified in most samples from the coastal half of the transect and was detected but not quantified in most samples in the inland half. We show that TCEP at this transect probably originated from the ocean around Antarctica. This study is the first to report the presence of TCEP on the Antarctica ice sheet, providing evidence of its long range transport from the source regions. This work also indicate that TCEP can transport hundreds of kilometers in the Antarctica. Copyright © 2013 Elsevier Ltd. All rights reserved.

Nitrous oxide measurements in the eastern tropical Pacific Ocean

NASA Technical Reports Server (NTRS)

Pierotti, D.; Rasmussen, R. A.

1980-01-01

The paper considers nitrous oxide measurements in the eastern tropical Pacific Ocean. The concentration of N2O in the marine air showed a direct relationship to the N2O in the surface sea water, with the highest N2O mixing ratios over highly supersaturated regions; water samples were also collected down to depths of 300 m at seven hydrocast stations. The stations showed two distribution patterns for N2O concentration vs depth for the region between the surface and 300 m; two stations in the oxygen deficient region off the coast of Peru showed considerable N2O super-saturation at all depths, and results indicate that the role of N2O in the nitrogen cycle of the ocean may be more complex than previously suggested.

Petroleum hydrocarbon pollution of urban topsoil in Ibadan city, Nigeria

DOE Office of Scientific and Technical Information (OSTI.GOV)

Onianwa, P.C.

The distribution of total petroleum hydrocarbon in topsoils from various parts of Ibadan city, Nigeria, was studied. Samples were selected from around the following zones: (a) railway tracks, (b) petrol stations, (c) refuse dumps, (d) residential areas, (e) high traffic density areas, (f) mechanical workshops, and (g) control zones. Contamination of the topsoil with hydrocarbons was significant only around petrol stations and mechanical workshops where the factors of accumulation were 10.1 and 4.72, respectively. The general trend in hydrocarbon levels was petrol station > mechanical workshop > refuse dumps > high traffic areas {ge} rail tracks > control residential areas.more » The results highlight the need to monitor urban environments that are remote from petroleum exploration activities for petroleum hydrocarbon contamination. 19 refs., 3 tabs.« less

Electric power scheduling - A distributed problem-solving approach

NASA Technical Reports Server (NTRS)

Mellor, Pamela A.; Dolce, James L.; Krupp, Joseph C.

1990-01-01

Space Station Freedom's power system, along with the spacecraft's other subsystems, needs to carefully conserve its resources and yet strive to maximize overall Station productivity. Due to Freedom's distributed design, each subsystem must work cooperatively within the Station community. There is a need for a scheduling tool which will preserve this distributed structure, allow each subsystem the latitude to satisfy its own constraints, and preserve individual value systems while maintaining Station-wide integrity.

[Study of the fluorescence characteristics of DOM from the Yangtze River and Jialing River around Chongqing's urban areas].

PubMed

Ji, Fang-ying; Li, Si; Zhou, Guang-ming; Yu, Dan-ni; Wang, Tu-jin; Cao, Lin; Tan, Xue-mei; Yang, Da-cheng; Zhou, Xiao-yi

2010-01-01

The fluorescence emission and excitation emission matrix (EEM) technologies were used to characterize the dissolved organic matter (DOM) in the water body of the Yangtze River and Jialing River around the Chongqing urban areas from April to August 2008. Concerning about the accidents of the Wenchuan's Earthquake in May and Tangjiashan Yansaihu's effects in June, and the high water period time in the summer in two months of July and August, from the EEM obtained from each sampling station and time, the composition, distribution and their changing features of the DOM in the two rivers were investigated as combined with the water samples' environmental parameters such as pH, DO, DOC with EEM's fingerprint features, f(450/500) etc; finally the bio-environment behavior effects of the three types of fluorescence peaks were elaborated, where humic-like, fulvic-like, and protein-like from the five sampling stations' EEMs during the five months were given detailed representation. From the experimental results obtained, the fluorescence peaks are mainly composed of two types of fluorophores: humic-like and protein-like in the two rivers around the Chongqing urban areas during the investigation in five months, the protein-like's peaks value in Jialing River is higher than the values in the Yangtze River, and all the fluorescence peaks in the two Rivers' water body decrease more or less after the two Rivers join in Chun Tan sampling station; the protein-like peak is notably higher after the "5 x 12" earthquake period time including May and June and high water period time, which mainly originated from terrestrial sources, but its intensities decreased observably while the water bodies of the two rivers joining together in the Chao Tianmen and Chun Tan's sampling station.

[AVS concentrations in Xinan Creek and the influencing factors].

PubMed

Liu, Xiao-Bing; Wen, Yan-Mao; Li, Feng; Wu, Chang-Hua; Duan, Zhi-Peng

2012-07-01

Sediment and overlying water samples were collected at 10 sampling stations at Xinan Creek, a tidal river in Pearl River Delta, and analyzed for physical and chemical characteristics as well as microbial incicators, in order to reveal the main factors dominating the spatial distribution of acid volatile sulfide (AVS). The effects of Eh, SRB OC and TS on the spatial distribution of AVS were investigated and the impact of AVS on the toxicity of heavy metals in the studied area was evaluated. The results showed that the range of AVS was 0.207-41.453 micromol x g(-1), with an average of 6.684 micromol x g(-1), which is relatively high compared to the results in other studies. The AVS value of the surface layer was higher than the bottom layer in 5 stations. The AVS values in both the surface layer and the bottom layer were highly variable, the coefficients of variation being 93.61% and 153.09% , respectively. The analytical results revealed that TS was the factor with the greatest impact on the spatial distribution of AVS, and the order was TS > OC > Eh > SRB. Potential ecological risk of heavy metals existed in 60% of the smpling stations based on the value of Sigma (SEM5-AVS), however, with the criterion of [Sigma(SEM5-AVS)]/foc, none of them had inacceptable ecological risk. Furthermore, in terms of single species of heavy metals, there was certain risk of toxic effect for all the five heavy metals (Cd, Ni, Cu, Zn and Pb). The above mentioned results will provide valuable data for the in-depth study of the formation mechanism of AVS and helpful reference for environmental impact assessment and scientific rehabilitation of heavy metals in polluted rivers.

Chlorination by-product concentration levels in seawater and fish of an industrialised bay (Gulf of Fos, France) exposed to multiple chlorinated effluents.

PubMed

Boudjellaba, D; Dron, J; Revenko, G; Démelas, C; Boudenne, J-L

2016-01-15

Chlorination is one of the most widely used techniques for biofouling control in large industrial units, leading to the formation of halogenated chlorination by-products (CBPs). This study was carried out to evaluate the distribution and the dispersion of these compounds within an industrialised bay hosting multiple chlorination discharges issued from various industrial processes. The water column was sampled at the surface and at 7 m depth (or bottom) in 24 stations for the analysis of CBPs, and muscle samples from 15 conger eel (Conger conger) were also investigated. Temperature and salinity profiles supported the identification of the chlorination releases, with potentially complex patterns. Chemical analyses showed that bromoform was the most abundant CBP, ranging from 0.5 to 2.2 μg L(-1) away from outlets (up to 10 km distance), and up to 18.6 μg L(-1) in a liquefied natural gas (LNG) regasification plume. However, CBP distributions were not homogeneous, halophenols being prominent in a power station outlet and dibromoacetonitrile in more remote stations. A seasonal effect was identified as fewer stations revealed CBPs in summer, probably due to the air and water temperatures increases favouring volatilisation and reactivity. A simple risk assessment of the 11 identified CBPs showed that 7 compounds concentrations were above the potential risk levels to the local marine environment. Finally, conger eel muscles presented relatively high levels of 2,4,6-tribromophenol, traducing a generalised impregnation of the Gulf of Fos to CBPs and a global bioconcentration factor of 25 was determined for this compound. Copyright © 2015 Elsevier B.V. All rights reserved.

Diversity of cyanobacteria and the presence of cyanotoxins in the epilimnion of Lake Yerevan (Armenia).

PubMed

Minasyan, Arevik; Christophoridis, Christophoros; Wilson, Alan E; Zervou, Sevasti-Kiriaki; Kaloudis, Triantafyllos; Hiskia, Anastasia

2018-04-26

This paper presents the first report of cyanobacteria and cyanotoxins from the South Caucasus region, in particular from Lake Yerevan (Armenia). Microcystis, Dolichospermum and Planktothrix were the key genera identified during the growing season. A trend of a remarkable increase in cyanobacterial densities was observed from 2012 to 2013 exhibiting bloom formation in June (by Nostoc linckia) with the highest values in June and August 2013, reaching up to 695.9*10 3  cells mL -1 . Seasonal dependence of cyanobacterial density on temperature, and temperature as a driver for cyanobacterial cells growth and development were suggested. Biogenic nutrients were identified as co-drivers determining species richness and dominance, as well as the distribution of phytoplankton in different parts of the reservoir. Cyanotoxin concentrations in the filtered biomass were reported during July 2012 for both stations of the reservoir (left and right bank). Microcystin-RR (MC-RR) was the most abundant and the most frequently observed cyanotoxin. Lower MC-LR concentrations were identified in all samples from both stations, with the highest values observed at the right bank in July 2012. [D-Asp 3 ]MC-RR, MC-YR, MC-HtyR, [D-Asp 3 ]MC-LR, MC-HilR, MC-WR, MC-LY and MC-LW were also identified in trace levels. Anatoxin-a (ANA) was reported in the samples from both stations during August 2012. Cylindrospermopsin (CYN) was present in trace concentrations in samples from both stations during July and in the sample from the left bank during September. Copyright © 2018 Elsevier Ltd. All rights reserved.

Anthropogenic radionuclide fluxes and distribution in bottom sediments of the cooling basin of the Ignalina Nuclear Power Plant.

PubMed

Marčiulionienė, D; Mažeika, J; Lukšienė, B; Jefanova, O; Mikalauskienė, R; Paškauskas, R

2015-07-01

Based on γ-ray emitting artificial radionuclide spectrometric measurements, an assessment of areal and vertical distribution of (137)Cs, (60)Co and (54)Mn activity concentrations in bottom sediments of Lake Drūkšiai was performed. Samples of bottom sediments from seven monitoring stations within the cooling basin were collected in 1988-1996 and 2007-2010 (in July-August). For radionuclide areal distribution analysis, samples from the surface 0-5 cm layer were used. Multi sample cores sliced 2 cm, 3 cm or 5 cm thick were used to study the vertical distribution of radionuclides. The lowest (137)Cs activity concentrations were obtained for two stations that were situated close to channels with radionuclide discharges, but with sediments that had a significantly smaller fraction of organic matter related to finest particles and consequently smaller radionuclide retention potential. The (137)Cs activity concentration was distributed quite evenly in the bottom sediments from other investigated monitoring stations. The highest (137)Cs activity concentrations in the bottom sediments of Lake Drūkšiai were measured in the period of 1988-1989; in 1990, the (137)Cs activity concentrations slightly decreased and they varied insignificantly over the investigation period. The obtained (238)Pu/(239,240)Pu activity ratio values in the bottom sediments of Lake Drūkšiai represented radioactive pollution with plutonium from nuclear weapon tests. Higher (60)Co and (54)Mn activity concentrations were observed in the monitoring stations that were close to the impact zones of the technical water outlet channel and industrial rain drainage system channel. (60)Co and (54)Mn activity concentrations in the bottom sediments of Lake Drūkšiai significantly decreased when operations at both INPP reactor units were stopped. The vertical distribution of radionuclides in bottom sediments revealed complicated sedimentation features, which may have been affected by a number of natural and anthropogenic factors resulting in mixing, resuspension and remobilization of sediments and radionuclides. The associated with particles (137)Cs flux was 129 Bq/(m(2) year). The (137)Cs transfer rate from water into bottom sediments was 14.3 year(-1) (or, the removal time was 25 days). The Kd value for (137)Cs in situ estimated from trap material was 80 m(3)/kg. The associated with particles (60)Co flux was 21 Bq/(m(2) year), when (60)Co activity concentration in sediment trap particles was 15.7 ± 5 Bq/kg. (60)Co activity concentration in soluble form was less than the minimum detectable activity (MDA = 1.3 Bq/m(3)). Then, the conservatively derived Kd value for (60)Co was >90 m(3)/kg. Copyright © 2015 Elsevier Ltd. All rights reserved.

Mixture distributions of wind speed in the UAE

NASA Astrophysics Data System (ADS)

Shin, J.; Ouarda, T.; Lee, T. S.

2013-12-01

Wind speed probability distribution is commonly used to estimate potential wind energy. The 2-parameter Weibull distribution has been most widely used to characterize the distribution of wind speed. However, it is unable to properly model wind speed regimes when wind speed distribution presents bimodal and kurtotic shapes. Several studies have concluded that the Weibull distribution should not be used for frequency analysis of wind speed without investigation of wind speed distribution. Due to these mixture distributional characteristics of wind speed data, the application of mixture distributions should be further investigated in the frequency analysis of wind speed. A number of studies have investigated the potential wind energy in different parts of the Arabian Peninsula. Mixture distributional characteristics of wind speed were detected from some of these studies. Nevertheless, mixture distributions have not been employed for wind speed modeling in the Arabian Peninsula. In order to improve our understanding of wind energy potential in Arabian Peninsula, mixture distributions should be tested for the frequency analysis of wind speed. The aim of the current study is to assess the suitability of mixture distributions for the frequency analysis of wind speed in the UAE. Hourly mean wind speed data at 10-m height from 7 stations were used in the current study. The Weibull and Kappa distributions were employed as representatives of the conventional non-mixture distributions. 10 mixture distributions are used and constructed by mixing four probability distributions such as Normal, Gamma, Weibull and Extreme value type-one (EV-1) distributions. Three parameter estimation methods such as Expectation Maximization algorithm, Least Squares method and Meta-Heuristic Maximum Likelihood (MHML) method were employed to estimate the parameters of the mixture distributions. In order to compare the goodness-of-fit of tested distributions and parameter estimation methods for sample wind data, the adjusted coefficient of determination, Bayesian Information Criterion (BIC) and Chi-squared statistics were computed. Results indicate that MHML presents the best performance of parameter estimation for the used mixture distributions. In most of the employed 7 stations, mixture distributions give the best fit. When the wind speed regime shows mixture distributional characteristics, most of these regimes present the kurtotic statistical characteristic. Particularly, applications of mixture distributions for these stations show a significant improvement in explaining the whole wind speed regime. In addition, the Weibull-Weibull mixture distribution presents the best fit for the wind speed data in the UAE.

Demonstration of Physical Separation/Leaching Methods for the Remediation of Heavy Metals Contaminated Soils at Small Arms Ranges.

DTIC Science & Technology

1997-09-01

8.8 WIND SOCK 8.9 SILT TRAP 8.10 BATTELLE SAMPLE PREPARATION AREA 8.11 RANGE 5 EXCAVATION PLAN 8.12 COMPONENTS THAT NEEDED MAINTENANCE, REPAIR...Pad Details 47 18 Soil Storage Bins 48 19 Power Distribution Station 49 20 Water Supply System 50 21 Wind Sock 50 22 Sample Preparation...washwater). Better process control, especially soil dewatering, would have reduced this occasional nuisance. The odor threshold for this acid is

Investigation of gasoline distributions within petrol stations: spatial and seasonal concentrations, sources, mitigation measures, and occupationally exposed symptoms.

PubMed

Sairat, Theerapong; Homwuttiwong, Sahalaph; Homwutthiwong, Kritsana; Ongwandee, Maneerat

2015-09-01

We measured levels of VOCs and determined the distributions of benzene concentrations over the area of two petrol stations in all three seasons. Using the concentrations and sampling positions, we created isoconcentration contour maps. The average concentrations ranged 18-1288 μg m(-3) for benzene and 12-81 μg m(-3) for toluene. The contour maps indicate that high-level contours of benzene were found not only at the fuel dispenser areas but also at the storage tank refilling points, open drainage areas where gasoline-polluted wastewater was flowing, and the auto service center located within the station area. An assessment of the benzene to toluene ratio contour plots implicates that airborne benzene and toluene near the fuel dispenser area were attributed to gasoline evaporation although one of the studied stations may be influenced by other VOC sources besides gasoline evaporation. Additionally, during the routine refilling of the underground fuel storage tanks by a tank truck, the ambient levels of benzene and toluene increased tremendously. The implementation of source control by replacing old dispensers with new fuel dispensers that have an efficient cutoff feature and increased delivery speed can reduce spatial benzene concentrations by 77%. Furthermore, a questionnaire survey among 63 service attendants in ten stations revealed that headache was the most reported health complaint with a response rate of 32%, followed by fatigue with 20%. These prominent symptoms could be related to an exposure to high benzene concentrations.

Population ecology and habitat preferences of juvenile flounder Platichthys flesus (Actinopterygii: Pleuronectidae) in a temperate estuary

NASA Astrophysics Data System (ADS)

Souza, Allan T.; Dias, Ester; Nogueira, Ana; Campos, Joana; Marques, João C.; Martins, Irene

2013-05-01

The European flounder Platichthys flesus is a widely distributed epibenthic species and an important component of demersal fish assemblages in the European Atlantic coastal waters. In Portuguese estuaries, this species reaches high densities, especially in Minho estuary (NW Iberian Peninsula, Europe), potentially playing an important role in the system's ecology. In this context, the population structure, production and the habitat use of juvenile P. flesus were investigated. Sampling took place monthly, from February 2009 until July 2010 along the entire estuarine gradient (5 sampling stations distributed in the first 29 km from the river mouth, with S1 located near the river mouth, S2 inside a salt marsh, S3 in a salinity transition zone, while S4 and S5 were located in the upper estuary). Flounder's density varied significantly among sampling stations and seasons (two-way PERMANOVA: p < 0.001), with the majority of the individuals being found during the spring (30.1%) and in S3 and S4 (72.6%). Males and females presented an even distribution, with a higher proportion of males observed during summer. Fish length also differed among sampling stations and seasons (two-way PERMANOVA: p < 0.001), with larger fishes being found in S1 during the autumn (168.50 ± 59.50 mm) and the smallest in S4 during the spring (33.80 ± 3.12 mm). Size classes associated differently with environmental variables, with larger juveniles being more abundant in the downstream areas of the estuary, whereas smaller juveniles were related to higher water temperatures, suggesting a habitat segregation of P. flesus of different sizes. The fish condition of P. flesus in Minho estuary was higher than in other systems, probably due to the dominance of juveniles on the population. Also, the densities found in this estuary were up to 32 times higher than in other locations, suggesting that Minho estuary is an important nursery area for the species. The estimated secondary production of P. flesus was lower than previous studies acknowledged in the system (0.037 g.WWm- 2.year- 1), indicating that the production estimates of this species in estuaries can vary considerably depending on of several factors such as the sampling year and strategy, population and fish size.

Reconstruction of far-field tsunami amplitude distributions from earthquake sources

USGS Publications Warehouse

Geist, Eric L.; Parsons, Thomas E.

2016-01-01

The probability distribution of far-field tsunami amplitudes is explained in relation to the distribution of seismic moment at subduction zones. Tsunami amplitude distributions at tide gauge stations follow a similar functional form, well described by a tapered Pareto distribution that is parameterized by a power-law exponent and a corner amplitude. Distribution parameters are first established for eight tide gauge stations in the Pacific, using maximum likelihood estimation. A procedure is then developed to reconstruct the tsunami amplitude distribution that consists of four steps: (1) define the distribution of seismic moment at subduction zones; (2) establish a source-station scaling relation from regression analysis; (3) transform the seismic moment distribution to a tsunami amplitude distribution for each subduction zone; and (4) mix the transformed distribution for all subduction zones to an aggregate tsunami amplitude distribution specific to the tide gauge station. The tsunami amplitude distribution is adequately reconstructed for four tide gauge stations using globally constant seismic moment distribution parameters established in previous studies. In comparisons to empirical tsunami amplitude distributions from maximum likelihood estimation, the reconstructed distributions consistently exhibit higher corner amplitude values, implying that in most cases, the empirical catalogs are too short to include the largest amplitudes. Because the reconstructed distribution is based on a catalog of earthquakes that is much larger than the tsunami catalog, it is less susceptible to the effects of record-breaking events and more indicative of the actual distribution of tsunami amplitudes.

Trace Element Cycling in Lithogenic Particles at Station ALOHA

NASA Astrophysics Data System (ADS)

Morton, P. L.; Weisend, R.; Landing, W. M.; Fitzsimmons, J. N.; Hayes, C. T.; Boyle, E. A.

2014-12-01

Trace element cycling in marine particles is influenced by atmospheric deposition, vertical export, biological uptake and remineralization, scavenging, and lateral transport processes. To investigate the cycling of lithogenic particles in the central North Pacific Ocean, surface and vertical profile samples of marine suspended particulate matter (SPM) were collected July-August 2012 during the HOE-DYLAN cruises at Station ALOHA. In the late summer, atmospheric dust inputs from the Gobi desert (which peak during the spring, April-May) were sparse, as indicated by low surface particulate Ti (pTi) concentrations. In contrast, surface pAl concentrations did not follow pTi trends as expected, but appear to be dominated by scavenging/uptake of dissolved Al during diatom blooms. Surface pMn concentrations were low, but vertical profiles of pMn and pMn/pTi reveal a strong sedimentary source at 200 m, originating from the Hawaiian continental shelf through a combination of redox mobilization and resuspension processes. The redox active elements Ce and Co can have chemistries similar to that of Mn, but in these samples the pCe and pCo distributions were distinct from Mn and each other in both surface trends and vertical profiles. Surface pREE (e.g., La, Ce, Pr) were highest during the earliest sampling events and quickly decreased to consistently low concentrations, while vertical distributions were characterized by scavenging onto biotic particles and mid-depth inputs. The surface particulate Co trend is similar to those of pAl and pP, while the pCo vertical profiles reflect surface enrichment but low concentrations and little variability at depth. A second, complementary poster is also being presented which examines the biological influence over particulate trace element cycling (Weisend et al., "Particulate Trace Element Cycling in a Diatom Bloom at Station ALOHA").

Technical status of the International Monitoring System for the Comprehensive Nuclear-Test-Ban Treaty

NASA Astrophysics Data System (ADS)

Grenard, P.

2009-04-01

The International Monitoring System (IMS) for the Comprehensive Nuclear Test-ban-Treaty Organization is a global Network of stations for detecting and providing evidence of possible nuclear explosions. Upon completion, the IMS will consist of 321 monitoring facilities and 16 radionuclide laboratories distributed worldwide in locations designated by the Treaty. Many of these sites are located in areas that are remote and difficult to access, posing major engineering and logistical challenges. The IMS uses seismic, hydroacoustic and infrasound monitoring waveform technologies to detect signals released from an explosion or a naturally occurring event (e.g. earthquakes) in the underground, underwater and atmospheric environments. The radionuclide technology as an integral part of the IMS uses air samples to collect particular matter from the atmosphere. Samples are then analyzed for evidence of physical products created by a nuclear explosion and carried through the atmosphere. The certification process of the IMS stations assures their compliance with the IMS technical requirements. In 2008 significant progress was made towards the completion of the IMS Network. So far 75% of the IMS stations have been built and certified.

Electric power scheduling: A distributed problem-solving approach

NASA Technical Reports Server (NTRS)

Mellor, Pamela A.; Dolce, James L.; Krupp, Joseph C.

1990-01-01

Space Station Freedom's power system, along with the spacecraft's other subsystems, needs to carefully conserve its resources and yet strive to maximize overall Station productivity. Due to Freedom's distributed design, each subsystem must work cooperatively within the Station community. There is a need for a scheduling tool which will preserve this distributed structure, allow each subsystem the latitude to satisfy its own constraints, and preserve individual value systems while maintaining Station-wide integrity. The value-driven free-market economic model is such a tool.

Location of Road Emergency Stations in Fars Province, Using Spatial Multi-Criteria Decision Making.

PubMed

Goli, Ali; Ansarizade, Najmeh; Barati, Omid; Kavosi, Zahra

2015-01-01

To locate the road emergency stations in Fars province based on using spatial multi-criteria decision making (Delphi method). In this study, the criteria affecting the location of road emergency stations have been identified through Delphi method and their importance was determined using Analytical Hierarchical Process (AHP). With regard to the importance of the criteria and by using Geographical Information System (GIS), the appropriateness of the existing stations with the criteria and the way of their distribution has been explored, and the appropriate arenas for creating new emergency stations were determined. In order to investigate the spatial distribution pattern of the stations, Moran's Index was used. The accidents (0.318), placement position (0.235), time (0.198), roads (0.160), and population (0.079) were introduced as the main criteria in location road emergency stations. The findings showed that the distribution of the existing stations was clustering (Moran's I=0.3). Three priorities were introduced for establishing new stations. Some arenas including Abade, north of Eghlid and Khoram bid, and small parts of Shiraz, Farashband, Bavanat, and Kazeroon were suggested as the first priority. GIS is a useful and applicable tool in investigating spatial distribution and geographical accessibility to the setting that provide health care, including emergency stations.

Controlling factors of harmful microalgae distribution in water column, biofilm and sediment in shellfish production area (South of Sfax, Gulf of Gabes) from southern Tunisia

NASA Astrophysics Data System (ADS)

Loukil-Baklouti, Amira; Feki-Sahnoun, Wafa; Hamza, Asma; Abdennadher, Moufida; Mahfoudhi, Mabrouka; Bouain, Abderrahmen; Jarboui, Othman

2018-01-01

The aim of this study was to investigate the spatio-temporal distribution of harmful microalgae coupled with environmental factors in the most important area for natural stocks of the grooved carpet shell Ruditapes decussatus in southern Tunisia. Sampling was performed monthly from May 2010 to April 2011 in five stations through the Tunisian National Monitoring Stations Network of Phytoplankton and Phycotoxins along the southern coasts of Sfax (Gulf of Gabes). The presence of harmful microalgae species was explored in three compartments: water column, biofilm and sediment. Our results revealed fourteen species were identified belonging to dinoflagellates and diatoms with higher densities during the summer period. The co-inertia plot analysis exhibited that the seasonal fluctuations of these species were controlled by the temperature as well as the nutrients (particularly nitrogenous). Ternary diagrams showed that biofilm was the most colonized compartment by toxic benthic dinoflagellates species, namely Amphidinium carterae, Prorocentrum rathymum, Prorocentrum concavum, Prorocentrum lima, Ostreopsis cf. ovata and Coolia monotis. In addition, these species were recorded simultaneously in the water column and the sediment, a fact that could be explained by the resuspension of these benthic dinoflagellates from the biofilm by hydrodynamics. The data suggest that harmful microalgae could be the source of toxins in the studied stations, which provide support to the implication of these results on the future sampling strategy of harmful microalgae in shellfish collecting areas in Tunisia.

Impacts on seafloor geology of drilling disturbance in shallow waters.

PubMed

Corrêa, Iran C S; Toldo, Elírio E; Toledo, Felipe A L

2010-08-01

This paper describes the effects of drilling disturbance on the seafloor of the upper continental slope of the Campos Basin, Brazil, as a result of the project Environmental Monitoring of Offshore Drilling for Petroleum Exploration--MAPEM. Field sampling was carried out surrounding wells, operated by the company PETROBRAS, to compare sediment properties of the seafloor, including grain-size distribution, total organic carbon, and clay mineral composition, prior to drilling with samples obtained 3 and 22 months after drilling. The sampling grid used had 74 stations, 68 of which were located along 7 radials from the well up to a distance of 500 m. The other 6 stations were used as reference, and were located 2,500 m from the well. The results show no significant sedimentological variation in the area affected by drilling activity. The observed sedimentological changes include a fining of grain size, increase in total organic carbon, an increase in gibbsite, illite, and smectite, and a decrease in kaolinite after drilling took place.

Distribution of agrochemicals in the lower Mississippi River and its tributaries

USGS Publications Warehouse

Pereira, W.E.; Rostad, C.E.; Leiker, T.J.

1990-01-01

The Mississippi River and its tributaries drain extensive agricultural regions of the Mid-Continental United States. Millions of pounds of herbicides are applied annually in these areas to improve crop yields. Many of these compounds are transported into the river from point and nonpoint sources, and eventually are discharged into the Gulf of Mexico. Studies being conducted by the U.S. Geological Survey along the lower Mississippi River and its major tributaries, representing a 2000 km river reach, have confirmed that several triazine and acetanilide herbicides and their degradation products are ubiquitous in this riverine system. These compounds include atrazine and its degradation products desethyl and desisopropylatrazine, cyanazine, simazine, metolachlor, and alachlor and its degradation products 2-chloro-2',6'-diethylacetanilide, 2-hydroxy-2',6-diethylacetanilide and 2,6-diethylaniline. Loads of these compounds were determined at 16 different sampling stations. Stream-load calculations provided information concerning (a) conservative or nonconservative behavior of herbicides; (b) point sources or nonpoint sources; (c) validation of sampling techniques; and (d) transport past each sampling station.

Outdoor field experience with autonomous RPC based stations

NASA Astrophysics Data System (ADS)

Lopes, L.; Assis, P.; Blanco, A.; Carolino, N.; Cerda, M. A.; Conceição, R.; Cunha, O.; Ferreira, M.; Fonte, P.; Luz, R.; Mendes, L.; Pereira, A.; Pimenta, M.; Sarmento, R.; Tomé, B.

2016-09-01

In the last two decades Resistive Plate Chambers were employed in the Cosmic Ray Experiments COVER-PLASTEX and ARGO/YBJ. In both experiments the detectors were housed indoors, likely owing to gas distribution requirements and the need to control environment variables that directly affect RPCs operational stability. But in experiments where Extended Air Shower (EAS) sampling is necessary, large area arrays composed by dispersed stations are deployed, rendering this kind of approach impossible. In this situation, it would be mandatory to have detectors that could be deployed in small standalone stations, with very rare opportunities for maintenance, and with good resilience to environmental conditions. Aiming to meet these requirements, we started some years ago the development of RPCs for Autonomous Stations. The results from indoor tests and measurements were very promising, both concerning performance and stability under very low gas flow rate, which is the main requirement for Autonomous Stations. In this work we update the indoor results and show the first ones concerning outdoor stable operation. In particular, a dynamic adjustment of the high voltage is applied to keep gas gain constant.

Polycyclic aromatic hydrocarbons in oysters and sediments from the Yatsushiro Sea, Japan: comparison of potential risks among PAHs, dioxins and dioxin-like compounds in benthic organisms.

PubMed

Nakata, Haruhiko; Uehara, Kiriko; Goto, Yuta; Fukumura, Miki; Shimasaki, Hideyuki; Takikawa, Kiyoshi; Miyawaki, Takashi

2014-01-01

Polycyclic aromatic hydrocarbons (PAHs) were analyzed in oysters collected from 18 stations in the Yatsushiro Sea, western Japan. PAHs were detected in all samples analyzed, and the highest concentration (mean 230 ng/g wet weight) was found in oysters from Tanoura Bay. The high molecular weight PAHs to low molecular weight PAHs ratios in oysters from Tanoura Bay were higher than at other stations. Sediment samples collected from 42 stations in Tanoura Bay were analyzed for PAHs to understand their concentrations and distribution. Higher concentrations were found in sediment samples at two stations in the southern inner bay (mean 30,200 ng/g dry weight), which were approximately two orders of magnitude higher than at a reference site. These observations strongly suggest severe contamination and significant sources of PAHs in Tanoura Bay. Dioxins and dioxin-like compounds (PCDFs, and non- and mono-ortho coplanar PCBs) were analyzed in sediments from eight stations in Tanoura Bay. The concentrations were comparable to, or lower than, at the reference sites, suggesting that there are no specific sources of these compounds in this bay. PAH, dioxins and dioxin-like compounds DR-CALUX relative potencies (REP) were applied to the sediment concentrations to evaluate the potential for toxicological effects on benthic organisms. PAHs made the highest contribution to the total REP concentration, supplying 99% of the total REP, followed by PCDDs (0.18%), PCDFs (0.04%), and PCBs (<0.001%). In this area, PAHs appear to be the most important Ah receptor binding chemicals for potential toxicity to benthic species. © 2013 Published by Elsevier Inc.

An assessment of the risk of element contamination of urban and industrial areas using Taraxacum sect. Ruderalia as a bioindicator.

PubMed

Fröhlichová, Alena; Száková, Jiřina; Najmanová, Jana; Tlustoš, Pavel

2018-02-19

Central Bohemia (Czech Republic) has highly developed industry and a dense rail network. Here, we aimed to determine the content of risk elements in dandelion plants (Taraxacum sect. Ruderalia) growing near train stations, industrial enterprises, and in the city parks of 16 cities in the Central Bohemian region. The highest element contents in the soils were found in industrial areas affected by the historical mining and smelting activities; contemporary industry showed no substantial effect on the soil element contents. The median values of element contents (As, Be, Cd, Co, Cr, Cu, Ni, Pb, and Zn) at the railway station sites were the highest among the monitored sites, where the differences between park and station sites were significant for Be, Co, and Zn. Although the intensity of the traffic at the individual stations differed, we found that long-term regular traffic enhanced the element contents in the soils and, subsequently, in the plants. For Cd, Co, Cr, Cu, Pb, V, and Zn, the highest median element contents were found in plant roots, regardless of the sampling site. For Cd and Zn, the contents in leaves were higher than in the inflorescences, and the opposite pattern was recorded for Co and Cu. As and Be were distributed equally among the plant parts. Among the sampling sites, the As, Be, Cd, Zn, and Pb contents in the plant roots tended to have higher median values at the station sites, confirming the results of our soil analyses. We detected a fairly good correlation between soil and plant content for cadmium, regardless of the sampling site, soil element content, or analyzed part of the plant. Thus, we propose that dandelion is a suitable bioindicator of cadmium pollution of soil.

Estimating site occupancy and abundance using indirect detection indices

USGS Publications Warehouse

Stanley, T.R.; Royle, J. Andrew

2005-01-01

Knowledge of factors influencing animal distribution and abundance is essential in many areas of ecological research, management, and policy-making. Because common methods for modeling and estimating abundance (e.g., capture-recapture, distance sampling) are sometimes not practical for large areas or elusive species, indices are sometimes used as surrogate measures of abundance. We present an extension of the Royle and Nichols (2003) generalization of the MacKenzie et al. (2002) site-occupancy model that incorporates length of the sampling interval into the, model for detection probability. As a result, we obtain a modeling framework that shows how useful information can be extracted from a class of index methods we call indirect detection indices (IDIs). Examples of IDIs include scent station, tracking tube, snow track, tracking plate, and hair snare surveys. Our model is maximum likelihood, and it can be used to estimate site occupancy and model factors influencing patterns of occupancy and abundance in space. Under certain circumstances, it can also be used to estimate abundance. We evaluated model properties using Monte Carlo simulations and illustrate the method with tracking tube and scent station data. We believe this model will be a useful tool for determining factors that influence animal distribution and abundance.

Accuracy assessment of BDS precision orbit determination and the influence analysis of site distribution

NASA Astrophysics Data System (ADS)

Chen, Ming; Guo, Jiming; Li, Zhicai; Zhang, Peng; Wu, Junli; Song, Weiwei

2017-04-01

BDS precision orbit determination is a key content of the BDS application, but the inadequate ground stations and the poor distribution of the network are the main reasons for the low accuracy of BDS precise orbit determination. In this paper, the BDS precise orbit determination results are obtained by using the IGS MGEX stations and the Chinese national reference stations，the accuracy of orbit determination of GEO, IGSO and MEO is 10.3cm, 2.8cm and 3.2cm, and the radial accuracy is 1.6cm,1.9cm and 1.5cm.The influence of ground reference stations distribution on BDS precise orbit determination is studied. The results show that the Chinese national reference stations contribute significantly to the BDS orbit determination, the overlap precision of GEO/IGSO/MEO satellites were improved by 15.5%, 57.5% and 5.3% respectively after adding the Chinese stations.Finally, the results of ODOP(orbit distribution of precision) and SLR are verified. Key words: BDS precise orbit determination; accuracy assessment；Chinese national reference stations；reference stations distribution；orbit distribution of precision

The study of Phosphorus distribution at Putrajaya Wetland

NASA Astrophysics Data System (ADS)

Mubin Zahari, Nazirul; Malek, Nur Farzana Fasiha Abdul; Fai, Chow Ming; Humaira Haron, Siti; Hafiz Zawawi, Mohd; Nazmi Ismail, Iszmir; Mohamad, Daud; Syamsir, Agusril; Sidek, Lariyah Mohd; Zakwan Ramli, Mohd; Ismail, Norfariza; Zubir Sapian, Ahmad; Noordin, Normaliza; Rahaman, Nurliyana Abdul; Muhamad, Yahzam; Mat Saman, Jarina

2018-04-01

This study is concerning phosphorus distribution in Putrajaya Wetland. Phosphorus is one of the important component in nutrients for living things be it aquatic or non – aquatic organisms. Total phosphorus (TP) results will give some information on the trophic status of surface water in water bodies. The focus of this study is to determine the total phosphorus concentration in Putrajaya Wetland which is in the inlet of the wetland then outlet of the wetland (Central Wetland Lake). The water sample is taken from Putrajaya Wetland and the test was conducted in the laboratory. The result from this study shows the results for total phosphorus according to month, sampling station and cells. Lowest total phosphate at the Central Wetland compare with all the wetland arms cells.

Occurrence, distribution and prey items of juvenile marbled sole Pseudopleuronectes yokohamae around a submarine groundwater seepage on a tidal flat in southwestern Japan

NASA Astrophysics Data System (ADS)

Hata, Masaki; Sugimoto, Ryo; Hori, Masakazu; Tomiyama, Takeshi; Shoji, Jun

2016-05-01

Occurrence, distribution and prey items of juvenile marbled sole Pseudopleuronectes yokohamae were investigated around a submarine groundwater seepage on a tidal flat in southwestern Japan. Spatial distribution of radon-222 (222Rn) concentration in water showed more submarine groundwater seepage in the offshore area. The lower salinities at offshore sampling stations corresponded with the highest 222Rn concentrations. Juvenile marbled sole were collected from March through June with seasonal peak in April in 2013 and 2014. Mean abundance of juvenile marbled sole was highest at the second most offshore station where high submarine groundwater seepage was indicated. Major prey items in the stomachs of the marbled sole at the post-settlement stage (10-40 mm) were small crustaceans such as cumaceans and gammarids, which were partially replaced with polychaetes in larger juveniles (40-50 mm). Abundance of these major prey items was also higher at offshore stations. A negative correlation between gammarid abundance and salinity indicated a higher concentration of gammarids around the area of high submarine groundwater seepage, a pattern not observed for the other major prey organisms. Stable isotope analysis showed greater dependence of post-settlement stage marbled sole on the small crustaceans with low δ13C indicating that nutrients of terrestrial origin contribute to production of the juvenile marbled sole on the tidal flat.

Further developments in cloud statistics for computer simulations

NASA Technical Reports Server (NTRS)

Chang, D. T.; Willand, J. H.

1972-01-01

This study is a part of NASA's continued program to provide global statistics of cloud parameters for computer simulation. The primary emphasis was on the development of the data bank of the global statistical distributions of cloud types and cloud layers and their applications in the simulation of the vertical distributions of in-cloud parameters such as liquid water content. These statistics were compiled from actual surface observations as recorded in Standard WBAN forms. Data for a total of 19 stations were obtained and reduced. These stations were selected to be representative of the 19 primary cloud climatological regions defined in previous studies of cloud statistics. Using the data compiled in this study, a limited study was conducted of the hemogeneity of cloud regions, the latitudinal dependence of cloud-type distributions, the dependence of these statistics on sample size, and other factors in the statistics which are of significance to the problem of simulation. The application of the statistics in cloud simulation was investigated. In particular, the inclusion of the new statistics in an expanded multi-step Monte Carlo simulation scheme is suggested and briefly outlined.

Evaluation of fisher (Pekania pennanti) restoration in Olympic National Park and the Olympic Recovery Area: 2014 annual progress report

USGS Publications Warehouse

Happe, Patricia J.; Jenkins, Kurt J.; Kay, Thomas J.; Pilgrim, Kristy L.; Schwartz, Michael K.; Lewis, Jeffrey C.; Aubry, Keith B.

2015-01-01

With the translocation and release of 90 fishers (Pekania pennanti) from British Columbia to Olympic National Park during 2008–2010, the National Park Service and Washington Department of Fish and Wildlife accomplished the first phase of fisher restoration in Washington State. Beginning in 2013, we initiated a new research project to determine the current status of fishers on Washington’s Olympic Peninsula 3–5 years after the releases and evaluate the short-term success of the restoration program. Objectives of the study are to determine the current distribution of fishers and proportion of the recovery area that is currently occupied by fishers, determine several genetic characteristics of the reintroduced population, and determine reproductive success of the founding animals through genetic studies. During 2014, we continued working with a broad coalition of cooperating agencies, tribes, and nongovernmental organizations (NGO) to collect data on fisher distribution and genetics using noninvasive sampling methods. The primary sampling frame consisted of 157 24-square-kilometer hexagons (hexes) distributed across all major land ownerships within the Olympic Peninsula target survey area. In 2014 we expanded the study by adding 58 more hexes to an expanded study area in response to incidental fisher observations outside of the target area obtained in 2013; 49 hexes were added south and 9 to the east of the target area. During 2014, federal, state, tribal and NGO biologists and volunteers established three baited motion-sensing camera stations, paired with hair snaring devices, in 80 hexes; 69 in the targeted area 11 in the expansion areas. Each paired camera/hair station was left in place for approximately 6 weeks, with three checks on 2-week intervals. We documented fisher presence in 5 of the 80 hexagons, and identified 5 different fishers through a combination of microsatellite DNA analyses and camera detections. All fisher detections were in the target area. These 5 individuals included 2 of the original founding population of 90, 1 of the 2 rescued and rehabilitated kits that were released in 2010, and 1 new recruit to the population (1 individual was not identified). Additionally, we identified more than 40 other species of wildlife at the baited camera stations. We also obtained eight incidental fisher observations through photographs and carcass retrieval. During 2015, we plan to sample 75 hexagons in the target area and 12 in the expansion area. We plan to sample all unsampled accessible hexes in the target area (26 hexes), and re-sample accessible hexes sampled in 2013 (49 hexes).

Using spatial, seasonal, and diel drift patterns of larval Lost River suckers Deltistes luxatus (Cypriniformes: Catostomidae) and shortnose suckers Chasmistes brevirostris (Cypriniformes: Catostomidae) to help identify a site for a water withdrawal structure on the Williamson River, Oregon

USGS Publications Warehouse

Ellsworth, Craig M.; Tyler, Torrey J.; VanderKooi, Scott P.

2010-01-01

A small irrigation diversion dam near Chiloquin, Oregon, was removed and replaced with a pump station to improve fish passage for Lost River suckers (Deltistes luxatus) and shortnose suckers (Chasmistes brevirostris) entering the Sprague River on their spawning migrations. During the developmental phase of the pump station, a need was identified to better understand the larval drift characteristics of these endangered catostomids in order to reduce entrainment into the irrigation system. The spatial, seasonal, and diel distribution of drifting larvae was measured during the 2004 spawning season at two proposed sites on the Williamson River where the pump station could be located. Larval drift for both species coincided with the irrigation season making them subject to entrainment into the irrigation system. Drift occurred almost exclusively at night with larvae entering the drift at sunset and exiting the drift at sunrise. Nighttime larval densities were concentrated near the surface and at midchannel at both sites. Densities were generally greater on the side of mid-channel with greater flow. During early morning sampling we detected a general shift in larval drift from surface to subsurface drift. We also observed an increase in larval densities towards the shore opposite from the proposed pump station at the upper site whereas larval densities remained high at midchannel at the lower site. During daytime sampling, the few larvae that were collected were distributed throughout the water column at both pump sites. This study found that larvae drifting during all time periods were generally distributed further across the cross section, deeper in the water column, and closer to where the proposed water withdrawal structure would be built at the downstream site when compared to the upstream site. Recommendations were provided to locate the withdrawal facility at the upstream site and operate it in a manner such that larval entrainment would likely be minimized.

Distribution of net-collected planktonic cnidarians along the northern Mid-Atlantic Ridge and their associations with the main water masses

NASA Astrophysics Data System (ADS)

Hosia, A.; Stemmann, L.; Youngbluth, M.

2008-01-01

Planktonic cnidarians and ctenophores were sampled with a multiple opening-closing net (Multinet) as well as a non-quantitative plankton net along the northern Mid-Atlantic Ridge (MAR) between Iceland and the Azores. Sixty-four species or genera of planktonic cnidarians (38 siphonophora, 21 hydromedusae, 5 scyphomedusae) and one genus of ctenophore were collected. Of these, Leuckartiara adnata and Clausophyes laetmata were new records for the area. Multinet samples collected from depths of 0-100, 100-500, 500-1000, 1000-1500 and 1500-2500 m at 11 stations were compared. Multivariate analysis of the data indicated that species composition and abundance along the ridge varied with the dominant water masses, with changes in the cnidarian zooplankton assemblage observed with regard to geographic location as well as depth. The surface waters of the two northernmost stations characterized by modified North Atlantic Water (MNAW) as well as the three southernmost stations characterized by North Atlantic Central Water (NACW) exhibited relatively high abundances (3284-13,915 individuals·1000 m -3) in the upper 100 m. No such peak was evident at the middle stations characterized by Subarctic Intermediate Water (SAIW), where the abundances in the upper three depth strata were consistently lower (57-863 individuals·1000 m -3). Across the study area, the lowest abundances were found in the 1500-2500 m stratum (0-56 ind.·1000 m -3). The main divergence in the species composition and abundance of planktonic cnidarians was observed at the Subpolar Front (SPF), which marked the boundary for the distribution of many species. The divergence at the SPF was strongest in the upper 500 m but observable down to 1500 m. Profoundly different epipelagic species assemblages were observed in SAIW and NACW on opposite sides of the SPF, with the distribution of several species of calycophoran siphonophores confined to the southern NACW. At mid-water depths, the species composition north of the SPF was possibly influenced by Labrador Sea Water (LSW). The highest diversity of planktonic cnidarians was observed in the surface waters south of the SPF and in the 100-1000 m range north of the SPF.

Distribution and sources of surfzone bacteria at Huntington Beach before and after disinfection on an ocean outfall-- a frequency-domain analysis.

PubMed

Noble, M A; Xu, J P; Robertson, G L; Rosenfeld, L K

2006-06-01

Fecal indicator bacteria (FIB) were measured approximately 5 days a week in ankle-depth water at 19 surfzone stations along Huntington Beach and Newport Beach, California, from 1998 to the end of 2003. These sampling periods span the time before and after treated sewage effluent, discharged into the coastal ocean from the local outfall, was disinfected. Bacterial samples were also taken in the vicinity of the outfall during the pre- and post-disinfection periods. Our analysis of the results from both data sets suggest that land-based sources, rather than the local outfall, were the source of the FIB responsible for the frequent closures and postings of local beaches in the summers of 2001 and 2002. Because the annual cycle is the dominant frequency in the fecal and total coliform data sets at most sampling stations, we infer that sources associated with local runoff were responsible for the majority of coliform contamination along wide stretches of the beach. The dominant fortnightly cycle in enterococci at many surfzone sampling stations suggests that the source for these relatively frequent bacteria contamination events in summer is related to the wetting and draining of the land due to the large tidal excursions found during spring tides. Along the most frequently closed section of the beach at stations 3N-15N, the fortnightly cycle is dominant in all FIBs. The strikingly different spatial and spectral patterns found in coliform and in enterococci suggest the presence of different sources, at least for large sections of beach. The presence of a relatively large enterococci fortnightly cycle along the beaches near Newport Harbor indicates that contamination sources similar to those found off Huntington Beach are present, though not at high enough levels to close the Newport beaches.

Characterization of carbon-14 generated by the nuclear power industry. Final report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Eabry, S.; Vance, J.N.; Cline, J.E.

1995-11-01

This report describes an evaluation of C-14 production rates in light-water reactors (LWRs) and characterization of its chemical speciation and environmental behavior. The study estimated the total production rate of the nuclide in operating PWRs and BWRs along with the assessment of the C-14 content of solid radwaste. The major source of production of C-14 in both PWR`s and BWRs was the activation of 0-17 in the water molecule and of N-14 dissolved in reactor coolant. The production of C-14 was estimated to range from 7 Ci/GW(e)-year to 11 Ci/GW(e)-year. The estimated range of the quantity of C-14 in LLWmore » was 1-2 Ci/ reactor-year which compares favorably with data obtained from shipping manifests. The environmental behavior of C-14 associated with low-level waste (LLW) disposal is greatly dependent upon its chemical speciation. This scoping study was performed to help identify the occurrence of inorganic and organic forms of C-14 in reactor coolant water and in primary coolant demineralization resins. These represent the major source for C-14 in LLW from nuclear power stations. Also, the behavior of inorganic and two of the organic forms of C-14 on soil uptake was determined by measuring distribution coefficients (Kd`s) on two soil types and a cement, using two different groundwater types. This study confirms that C-14 concentrations are significantly higher in the primary coolant from PWR stations compared to BWR stations. The C-14 followed trends of Co-60 generation during primary coolant demineralization at all but one of the stations examined. However, the C-14/Co-60 activity ratios measured by this study in resin samples through which samples of coolant were drawn were about 8 to 42 times higher than those reported for waste samples in the industry data base for PWR stations, and 15 to 730 times lower for the BWR stations.« less

DNA Barcoding of Ichthyoplankton in Hampton Roads Bay Estuary

NASA Astrophysics Data System (ADS)

Wilkins, N.; Rodríguez, Á. E.

2016-02-01

Zooplankton is composed of animals that drift within the water column. The study of zooplankton biodiversity and distribution is crucial to understand oceanic ecosystems and anticipate the effects of climate change. In this study our focus is on ichthyoplankton (fish eggs and larvae). Our aim is to employ molecular genetic techniques such as DNA barcoding to begin a detailed characterization of ichthyoplankton diversity, abundance and community structure in the Hampton Roads Bay Estuary (HRBE). A sampling of zooplankton was performed on June 19, 2015. Samples were taken with a 0.5m, 200 µm mesh net in triplicates at two stations: inner shore in the mouth of Jones Creek and 5 miles off Hampton in the lower part of Chesapeake Bay. Physical parameters (dissolved oxygen, salinity, and temperature and water transparency) were measured simultaneously. Species were identified by DNA barcoding using the mitochondrial DNA (mtDNA) of the Cytochrome Oxidase 1 (CO1) gene. Fish eggs were identified from Opistonema oglinum (Atlantic Thread Herring) at the offshore stations while, Anchoa mitchilli was found at both stations. These species are common to the area and as observed, differences in species between stations were found. O. oglinum eggs were found in the offshore stations, which is their reported habitat. A. mitchilli eggs were found in both stations; both known to exhibit a wider salinity tolerance. This work indicates that using mtDNA-CO1 barcoding is suitable to identify ichthyoplankton to the species level and helped validate DNA barcoding as a faster taxonomic approach. The long term objective of this project is to provide taxonomic composition and biodiversity assessment of ichthyoplankton in HRBE. This data will be a reference for broad monitoring programs; for a better understanding and management of ecologically and commercially important species in the HRBE. Monthly samplings will be performed for a year beginning September 2015.

Geochemical distribution, fractionation and contamination assessment of heavy metals in marine sediments of the Asaluyeh port, Persian Gulf.

PubMed

Delshab, Hossein; Farshchi, Parvin; Keshavarzi, Behnam

2017-02-15

In this study, total concentration and speciation of heavy metals in sediments of the Asaluyeh, one of the Iran's largest commercial ports, are investigated. 48 sediment samples were collected and analyzed for trace and major elements. Sediment quality guidelines along with calculated enrichment factors and trace metal profiles indicate that Asaluyeh port is threated by contamination, especially with respect to Hg and Cu. Normalization to Sc indicated high enrichment factors in the sediments following the decreasing order of: Hg>Cu>As>Ni>Zn>Pb≈Cr≈Mn>Co≈V≈Fe≈Al. Hg displayed the greatest potential ecological risk factor among sampling stations. The results of sequential extraction procedure revealed that in some stations >50% of Mn, V, Cu and Zn occur in potentially mobile phases and therefore are more readily mobilized in the sediments of the study area. Copyright © 2016 Elsevier Ltd. All rights reserved.

Distribution, enrichment and accumulation of heavy metals in coastal sediments of Alang-Sosiya ship scrapping yard, India.

PubMed

Reddy, M Srinivasa; Basha, Shaik; Sravan Kumar, V G; Joshi, H V; Ramachandraiah, G

2004-06-01

Since its inception in 1982, the Alang-Sosiya yard has become the largest ship scrapping works in the world. Several hundreds of ships arrive every year. The degree of heavy metal contamination has been studied in bulk and fine sediments from the intertidal zone of this ship scrapping yard, two stations, one on either side at 5 km distance and one reference station 60 km distance near Mahuva, towards the south. The samples have been subjected to a total digestion technique and analysed for elements: Cd, Co, Cu, Cr, Fe, Mn, Ni, Pb, Zn and Al, and %TOC. The absolute metal concentrations reflected variations in BF and FF sediment samples with organic matter content. Enrichment factors (EF) and geoaccumulation indices (Igeo) have been calculated and the relative contamination levels are assessed at these sites. At Alang-Sosiya, the enrichment of heavy metals has been observed to be relatively high.

47 CFR 73.626 - DTV distributed transmission systems.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 47 Telecommunication 4 2010-10-01 2010-10-01 false DTV distributed transmission systems. 73.626... RADIO BROADCAST SERVICES Television Broadcast Stations § 73.626 DTV distributed transmission systems. (a... distributed transmission system (DTS). Except as expressly provided in this section, DTV stations operating a...

US GEOLOGICAL SURVEY'S NATIONAL SYSTEM FOR PROCESSING AND DISTRIBUTION OF NEAR REAL-TIME HYDROLOGICAL DATA.

USGS Publications Warehouse

Shope, William G.; ,

1987-01-01

The US Geological Survey is utilizing a national network of more than 1000 satellite data-collection stations, four satellite-relay direct-readout ground stations, and more than 50 computers linked together in a private telecommunications network to acquire, process, and distribute hydrological data in near real-time. The four Survey offices operating a satellite direct-readout ground station provide near real-time hydrological data to computers located in other Survey offices through the Survey's Distributed Information System. The computerized distribution system permits automated data processing and distribution to be carried out in a timely manner under the control and operation of the Survey office responsible for the data-collection stations and for the dissemination of hydrological information to the water-data users.

Variation in zooplankton prey distribution determines marine foraging distributions of breeding Cassin's Auklet

NASA Astrophysics Data System (ADS)

Bertram, Douglas F.; Mackas, David L.; Welch, David W.; Boyd, W. Sean; Ryder, John L.; Galbraith, Moira; Hedd, April; Morgan, Ken; O'Hara, Patrick D.

2017-11-01

To investigate the causal basis for patterns of seabird foraging distributions during breeding we integrated data from ship-board seabird and zooplankton surveys, aerial radio telemetry, and colony-based research programs. We examined the marine distributions of Cassin's Auklet (Ptychoramphus aleuticus) breeding on Triangle Island, in the Northeast Pacific off the coast of B.C., Canada using surveys conducted in 1999, 2000, and 2001. Concurrently, we sampled zooplankton at 16 stations along a cross shelf transect in the vicinity of Triangle Island. In 1999 and 2000, when populations of the preferred copepod prey Neocalanus cristatus were available at deep-water stations (1000-2000 m), the majority of the auklets were concentrated SW of the colony 40-75 km offshore and parallel to, but 35 -50 km beyond the shelf break in deep water (1200-2000 m). Birds did not fly farther out to sea to where prey was five times more abundant when N. cristatus could be found at lower abundance levels, closer to the colony. In 2001, N. cristatus were virtually absent at the deep-water stations, likely as a result of massive salp (family Salpidae) aggregations which may have consumed and displaced the seabirds' preferred prey. We demonstrate that while birds were still able to locate and provision chicks with N. cristatus in 2001, they had to forage farther away from the colony in order to do so. Our telemetry results are generally consistent with analyses of at-sea distributions of Cassin's Auklets derived from ship-board surveys (1990-2010) both of which have contributed to the design of the proposed Scott Islands marine National Wildlife Area, the first of its kind in Canada.

Investigation of methods for hydroclimatic data homogenization

NASA Astrophysics Data System (ADS)

Steirou, E.; Koutsoyiannis, D.

2012-04-01

We investigate the methods used for the adjustment of inhomogeneities of temperature time series covering the last 100 years. Based on a systematic study of scientific literature, we classify and evaluate the observed inhomogeneities in historical and modern time series, as well as their adjustment methods. It turns out that these methods are mainly statistical, not well justified by experiments and are rarely supported by metadata. In many of the cases studied the proposed corrections are not even statistically significant. From the global database GHCN-Monthly Version 2, we examine all stations containing both raw and adjusted data that satisfy certain criteria of continuity and distribution over the globe. In the United States of America, because of the large number of available stations, stations were chosen after a suitable sampling. In total we analyzed 181 stations globally. For these stations we calculated the differences between the adjusted and non-adjusted linear 100-year trends. It was found that in the two thirds of the cases, the homogenization procedure increased the positive or decreased the negative temperature trends. One of the most common homogenization methods, 'SNHT for single shifts', was applied to synthetic time series with selected statistical characteristics, occasionally with offsets. The method was satisfactory when applied to independent data normally distributed, but not in data with long-term persistence. The above results cast some doubts in the use of homogenization procedures and tend to indicate that the global temperature increase during the last century is between 0.4°C and 0.7°C, where these two values are the estimates derived from raw and adjusted data, respectively.

Physical Habitat and Energy Inputs Determine Freshwater Invertebrate Communities in Reference and Cranberry Farm Impacted Northeastern Coastal Zone Streams

NASA Astrophysics Data System (ADS)

Lander, D. M. P.; McCanty, S. T.; Dimino, T. F.; Christian, A. D.

2016-02-01

The River Continuum Concept (RCC) predicts stream biological communities based on dominant physical structures and energy inputs into streams and predicts how these features and corresponding communities change along the stream continuum. Verifying RCC expectations is important for creating valid points of comparison during stream ecosystem evaluation. These reference expectations are critical for restoration projects, such as the restoration of decommissioned cranberry bogs. Our research compares the physical habitat and freshwater invertebrate functional feeding groups (FWIFFG) of reference, active cranberry farming, and cranberry farm passive restoration sites in Northeastern Coastal Zone streams of Massachusetts to the specific RCC FWIFFG predictions. We characterized stream physical habitat using a semi-quantitative habitat characterization protocol and sampled freshwater invertebrates using the U.S. EPA standard 20-jab multi-habitat protocol. We expected that stream habitat would be most homogeneous at active farming stations, intermediate at restoration stations, and most heterogeneous at reference stations. Furthermore, we expected reference stream FWIFFG would be accurately predicted by the RCC and distributions at restoration and active sites would vary significantly. Habitat data was analyzed using a principle component analysis and results confirmed our predictions showing more homogeneous habitat for the active and reference stations, while showing a more heterogeneous habitat at the reference stations. The FWIFFG chi-squared analysis showed significant deviation from our specific RCC FWIFFG predictions. Because published FWIFFG distributions did not match our empirical values for a least disturbed Northeastern Coastal Zone headwater stream, using our data as a community structure template for current and future restoration projects is not recommend without further considerations.

Biological community structure on patch reefs in Biscayne National Park, FL, USA

USGS Publications Warehouse

Kuffner, Ilsa B.; Grober-Dunsmore, Rikki; Brock, John C.; Hickey, T. Don

2010-01-01

Coral reef ecosystem management benefits from continual quantitative assessment of the resources being managed, plus assessment of factors that affect distribution patterns of organisms in the ecosystem. In this study, we investigate the relationships among physical, benthic, and fish variables in an effort to help explain the distribution patterns of organisms on patch reefs within Biscayne National Park, FL, USA. We visited a total of 196 randomly selected sampling stations on 12 shallow (<10 m) patch reefs and measured physical variables (e.g., substratum rugosity, substratum type) and benthic and fish community variables. We also incorporated data on substratum rugosity collected remotely via airborne laser surveying (Experimental Advanced Airborne Research Lidar—EAARL). Across all stations, only weak relationships were found between physical, benthic cover, and fish assemblage variables. Much of the variance was attributable to a “reef effect,” meaning that community structure and organism abundances were more variable at stations among reefs than within reefs. However, when the reef effect was accounted for and removed statistically, patterns were detected. Within reefs, juvenile scarids were most abundant at stations with high coverage of the fleshy macroalgae Dictyota spp., and the calcified alga Halimeda tuna was most abundant at stations with low EAARL rugosity. Explanations for the overwhelming importance of “reef” in explaining variance in our dataset could include the stochastic arrangement of organisms on patch reefs related to variable larval recruitment in space and time and/or strong historical effects due to patchy disturbances (e.g., hurricanes, fishing), as well as legacy effects of prior residents (“priority” effects).

Effect of Sampling Period on Flood Frequency Distributions in the Susquehanna Basin

NASA Astrophysics Data System (ADS)

Kargar, M.; Beighley, R. E.

2010-12-01

Flooding is a devastating natural hazard that claims many human lives and significantly impact regional economies each year. Given the magnitude of flooding impacts, significant resources are dedicated to the development of forecasting models for early warning and evacuation planning, construction of flood defenses (levees/dams) to limit flooding, and the design of civil infrastructure (bridges, culverts, storm sewers) to convey flood flows without failing. In all these cases, it is particularly important to understand the potential flooding risk in terms of both recurrence interval (i.e., return period) and magnitude. Flood frequency analysis (FFA) is a form of risk analysis used to extrapolate the return periods of floods beyond the gauged record. The technique involves using observed annual peak flow discharge data to calculate statistical information such as mean values, standard deviations, skewness, and recurrence intervals. Since discharge data for most catchments have been collected for periods of time less than 100 years, the estimation of the design discharge requires a degree of extrapolation. This study focuses on the assessment and modifications of flood frequency based discharges for sites with limited sampling periods. Here, limited sampling period is intended to capture two issues: (1) limited number of observations to adequately capture the flood frequency signal (i.e., minimum number of annual peaks needed) and (2) climate variability (i.e., sampling period contains primarily “wet” or “dry” periods only). Total of 34 gauges (more than 70 years of data) spread throughout the Susquehanna River basin (71,000 sq km) were used to investigate the impact of sampling period on flood frequency distributions. Data subsets ranging from 10 years to the total number of years available were created from the data for each gauging station. To estimate the flood frequency, the Log Pearson Type III distribution was fit to the logarithms of instantaneous annual peak flows following Bulletin 17B guidelines of the U.S. Interagency Advisory Committee on Water Data. The resulting flood frequencies from these subsets were compared to the results from the entire record at each gauge. Based on the analysis, the minimum number of years required to obtain a reasonable flood frequency distribution was determined for each gauge. In addition, a method to adjust flood frequency distribution at a given gauging station with limited data based on other locations with longer periods of records was developed.

System for Packaging Planetary Samples for Return to Earth

NASA Technical Reports Server (NTRS)

Badescu, Mircea; Bar-Cohen, Yoseph; Backes, paul G.; Sherrit, Stewart; Bao, Xiaoqi; Scott, James S.

2010-01-01

A system is proposed for packaging material samples on a remote planet (especially Mars) in sealed sample tubes in preparation for later return to Earth. The sample tubes (Figure 1) would comprise (1) tubes initially having open tops and closed bottoms; (2) small, bellows-like collapsible bodies inside the tubes at their bottoms; and (3) plugs to be eventually used to close the tops of the tubes. The top inner surface of each tube would be coated with solder. The side of each plug, which would fit snugly into a tube, would feature a solder-filled ring groove. The system would include equipment for storing, manipulating, filling, and sealing the tubes. The containerization system (see Figure 2) will be organized in stations and will include: the storage station, the loading station, and the heating station. These stations can be structured in circular or linear pattern to minimize the manipulator complexity, allowing for compact design and mass efficiency. The manipulation of the sample tube between stations is done by a simple manipulator arm. The storage station contains the unloaded sample tubes and the plugs before sealing as well as the sealed sample tubes with samples after loading and sealing. The chambers at the storage station also allow for plug insertion into the sample tube. At the loading station the sample is poured or inserted into the sample tube and then the tube is topped off. At the heating station the plug is heated so the solder ring melts and seals the plug to the sample tube. The process is performed as follows: Each tube is filled or slightly overfilled with sample material and the excess sample material is wiped off the top. Then, the plug is inserted into the top section of the tube packing the sample material against the collapsible bellowslike body allowing the accommodation of the sample volume. The plug and the top of the tube are heated momentarily to melt the solder in order to seal the tube.

Design considerations for examining trends in avian abundance using point counts: examples from oak woodlands

Treesearch

Kathryn L. Purcell; Sylvia R. Mori; Mary K. Chase

2005-01-01

We used data from two oak-woodland sites in California to develop guidelines for the design of bird monitoring programs using point counts. We used power analysis to determine sample size adequacy when varying the number of visits, count stations, and years for examining trends in abundance. We assumed an overdispersed Poisson distribution for count data, with...

Preliminary Observations of Noise Spectra at the SRO and ASRO Stations

USGS Publications Warehouse

Peterson, Jon

1980-01-01

Introduction The seismic noise spectra presented in this report were derived from SRO and ASRO station data for the purpose of evaluating the performance of the seismic instruments. They are also useful for constructing a spectral estimate of earth noise at a quiet site based on noise samples obtained from a network of globally distributed sites. It is hoped that the spectra will be usefull for other purposes as well. The term 'noise' is used here to describe the ambient signals recorded during a quiet period when earthquake signals have not been detected by visual inspectino of the analog seismogram. The total recorded noise is the sum of instrumental noise, environmental noise (such as effects of temperature, pressure, wind), earth background noise from both natural and cultural sources, and very possibly low-level signals from earthquakes that cannot be visually identified. It is not possible to separate and quantify the signals generated by these independent noise sources using a single sample of station data, although instrumental problems may be indicated by gross changes of noise levels, if the changes are not in the microseismic bands. Since seismic data at the SRO and ASRO stations are recorded in a digital format, spectral computations can be automated so that station noise levels can be monitored as part of data-review procedures. The noise spectra presented in this study are intended to serve as an initial baseline against which relative changes in noise levels can be measured. Total noise power was computed separately for the short- and long-period bands, which are recorded separately at the stations. Power spectral densities were derived by averaging the spectral estimates of a number of contiguous dat segments. The mean value and slope were removed from each segment, cosine-tapered windows were applied, and the estimates were obtained using a fast Fourier transform. In the short-period analyses 16 segments were used, each segment being 1024 samples in length. Because the sampling interval is .05 seconds, the total record length is nearly 13.7 minutes. Normally, the short-period SRO and ASRO data are recorded in an event-only mode. However, several days of continuous short-period data were acquired from most stations for the purpose of this study. Where there was appreciable diurnal variation in short-period noise, spectral data were computed for both day and night intervals. In most cases the long-period spectral densities were obtained by averagin the estimates from 16 data segments, each segment having a length of 2048 samples. Since the long-period sampling interval in 1 second, the total record length used was nearly 9.1 hours. In a few instances, a smaller number of segments was averaged. Spectral data were computed from the vertical-component short-period signals and all three components of long-period signals. All of the spectral plots have been corrected for known instrument response and presented in units of earth displacement. With a few exceptions, the samples of noise data used were acquired during the early months of 1980, winter at some of the stations and summer at others. The starting times for the intervals analyzed are listed in Table 1. A seasonal variation of noise levels in microseismic bands is to be expected. However, none of the stations were experiencing a noticeably high level of microseisms during the intervals analyzed. Weltman and others (1979) have studied and reported daily and seasonal RMS (root-mean-square) noise trends at the SRO and ASRO stations.

Spatial distribution and vertical migrations of fish larvae communities off Northwestern Iberia sampled with LHPR and Bongo nets

NASA Astrophysics Data System (ADS)

Garrido, Susana; Santos, A. Miguel P.; dos Santos, Antonina; Ré, Pedro

2009-10-01

The spatial distribution and diel vertical migration of fish larvae were studied in relation to the environmental conditions off NW Iberia during May 2002. Larvae from 23 families were identified, the most abundant were the Clupeidae, Gobiidae, Callionymidae, Blenniidae, Sparidae and Labridae. Sardina pilchardus was the most abundant species, mean concentrations 1 order of magnitude higher than the other fish larvae species. Larval horizontal distribution was mainly related to upwelling-driven circulation, resulting in an offshore increase of larval abundance while the vertical distribution was closely associated to the Western Iberia Buoyant Plume. Despite this general trend, taxon-specific relationships between the distribution of larvae and environmental variables were observed, and temperature was an important regressor explaining the distribution of most taxa. A comparison between ichthyoplankton samples collected alternatively with the LHPR and Bongo nets resulted in captures of larvae ≈1 order of magnitude higher for the LHPR, probably related to its higher towing speed. The spatial distribution and relative composition of larvae were also different for both nets, although the most frequent/abundant groups were the same. A fixed station sampled for 69-h showed diel vertical migrations performed by the larvae, with the highest larval concentrations occurring at surface layers during the night and most larvae being found in the neuston layer only during that period.

Density and white shrimp growth pattern (penaeus merguiensis) in kampung nipah waters of perbaungan north sumatera

NASA Astrophysics Data System (ADS)

Natalia Silaen, Sri; Budi Mulya, Miswar

2018-03-01

The purpose of the study was to determine the density and pattern of growth of white shrimp (Penaeus merguiensis)of the village Nipah waters. The data collection was conducted by sampling using nets and fishing gear “Langge” (a tool) to determine the density of the three observation stations. The result showed that the distribution of white shrimp in the waters of the estuary and surrounding degraded over the past ten years. The highest density at station II is 0.56 and 5/m2 and at least at the third station as much as 0.42 and 6/m2 The correlation between the density of shrimp with depth as well as the fraction of the base substrate showed that only the depth of the waters who has any significant correlation with the density of shrimp, although the closeness of the relationship is small.

Biomonitoring of marine vertebrates in Monterey Bay using eDNA metabarcoding.

PubMed

Andruszkiewicz, Elizabeth A; Starks, Hilary A; Chavez, Francisco P; Sassoubre, Lauren M; Block, Barbara A; Boehm, Alexandria B

2017-01-01

Molecular analysis of environmental DNA (eDNA) can be used to assess vertebrate biodiversity in aquatic systems, but limited work has applied eDNA technologies to marine waters. Further, there is limited understanding of the spatial distribution of vertebrate eDNA in marine waters. Here, we use an eDNA metabarcoding approach to target and amplify a hypervariable region of the mitochondrial 12S rRNA gene to characterize vertebrate communities at 10 oceanographic stations spanning 45 km within the Monterey Bay National Marine Sanctuary (MBNMS). In this study, we collected three biological replicates of small volume water samples (1 L) at 2 depths at each of the 10 stations. We amplified fish mitochondrial DNA using a universal primer set. We obtained 5,644,299 high quality Illumina sequence reads from the environmental samples. The sequence reads were annotated to the lowest taxonomic assignment using a bioinformatics pipeline. The eDNA survey identified, to the lowest taxonomic rank, 7 families, 3 subfamilies, 10 genera, and 72 species of vertebrates at the study sites. These 92 distinct taxa come from 33 unique marine vertebrate families. We observed significantly different vertebrate community composition between sampling depths (0 m and 20/40 m deep) across all stations and significantly different communities at stations located on the continental shelf (<200 m bottom depth) versus in the deeper waters of the canyons of Monterey Bay (>200 m bottom depth). All but 1 family identified using eDNA metabarcoding is known to occur in MBNMS. The study informs the implementation of eDNA metabarcoding for vertebrate biomonitoring.

Impact of organic matter source and quality on living benthic foraminiferal distribution on a river-dominated continental margin: A study of the Portuguese margin

NASA Astrophysics Data System (ADS)

Dessandier, Pierre-Antoine; Bonnin, Jérôme; Kim, Jung-Hyun; Bichon, Sabrina; Deflandre, Bruno; Grémare, Antoine; Sinninghe Damsté, Jaap S.

2016-06-01

Living (rose Bengal stained) benthic foraminifera were investigated on surface sediments from 23 stations from the river-dominated northwestern Portuguese margin. Samples were collected in March 2011, following the period of the maximum rainfall over the Iberian Peninsula, between 20 and 2000 m water depth along five cross-margin transects. Four of them are located off the Douro, Mondego, Tagus, and Sado Rivers and one off the Estremadura coast. The major objectives of this study are (1) to assess the impact of organic matter of various origin and quality on the benthic foraminifera and (2) to investigate the spatial differences of faunal distribution from coastal waters to the deep sea under river influences. To do this, sedimentological and biogeochemical characteristics of the sediments were identified by measuring grain size, oxygen penetration depth, total organic carbon (TOC) content, stable carbon isotopic composition of TOC (δ13CTOC) and concentration of pigments and amino acids. Based on the principal component and cluster analyses of the environmental data, three major geographical groups are identified: (1) deep stations, (2) coastal and middle slope stations, and (3) shelf stations under river influence. At the deepest stations, species are associated with high organic matter (OM) quantity but low OM quality, where Uvigerina mediterranea, Hoeglundina elegans, and agglutinated species such as Reophax scorpiurus or Bigenerina nodosaria are dominant. All stations off the Sado River, which is the most affected area by the anthropogenic influence, are also characterized by high quantity but low quality of OM with the minimum faunal density and diversity within the study area. Middle slope stations are associated with low OM content and coarse sediments (Q50) with the predominance of N. scaphum. Shallow shelf stations close to the Douro and Tagus River mouths show a dominance of taxa (e.g., Ammonia beccarii, Bulimina aculeata, Eggerelloides scaber, Nonion scaphum, Cancris auriculus, and Quinqueloculina seminula) adapted to environments characterized by high OM quality (high fresh chlorophyll (Chl a/Phaeo)) and available amino acids (enzymatically hydrolyzable amino acid (EHAA)/total enzymatically hydrolyzable amino acid (THAA)). The Biotic and Environmental linking analysis suggests that the benthic foraminiferal distribution is mostly controlled by three environmental parameters, i.e., TOC (quantity), EHAA/THAA (quality), and δ13CTOC (source). Hence, this study clearly highlights that the quantitative and qualitative inputs of OM and its source are the most important factors controlling the living benthic foraminiferal distribution with clear influences between the different rivers. This study also suggests a good tolerance of several species for river discharges where the OM quality is high.

Distribution and mass loss of volatile organic compounds in the surficial aquifer at sites FT03, LF13, and WP14/LF15, Dover Air Force Base, Delaware, November 2000-February 2001

USGS Publications Warehouse

Barbaro, Jeffrey R.; Neupane, Pradumna P.

2002-01-01

Ground-water and surface-water sampling was conducted in the natural attenuation study area in the East Management Unit of Dover Air Force Base, Delaware to determine the distributions of volatile organic compounds in the vicinity of four sites?Fire Training Area Three, the Rubble Area Landfill, the Receiver Station Landfill, and the Liquid Waste Disposal Landfill. This work was done by the U.S. Geological Survey, in cooperation with the U.S. Air Force, as part of an ongoing assessment of the effectiveness of natural attenuation at these sites. The specific objectives of the study were to (1) determine the areal and vertical extent of the contaminant plumes and source areas, (2) measure volatile organic compound concentrations in ground-water discharge areas and in surface water under base-flow conditions, (3) evaluate the potential for off-site migration of the mapped plumes, and (4) estimate the amount of mass loss downgradient of the Liquid Waste Disposal and Receiver Station Landfills. A direct-push drill rig and previously installed multi-level piezometers were used to determine the three-dimensional distributions of volatile organic compounds in the 30?60-foot-thick surficial aquifer underlying the natural attenuation study area. A hand -driven mini-piezometer was used to collect ground-water samples in ground-water discharge areas. A total of 319 ground-water and 4 surface-water samples were collected from November 2000 to February 2001 and analyzed for chlorinated solvents and fuel hydrocarbons. The contaminant plumes migrating from Fire Training Area Three and the Rubble Area Landfill are approximately 500 feet and 800 feet, respectively, in length. These plumes consist predominantly of cis-1,2-dichloroethene, a daughter product, indicating that extensive dechlorination of tetrachloroethene and trichloroethene has occurred at these sites. With an approximate length of 2,200 feet, the plume migrating from the Receiver Station and Liquid Waste Disposal Landfills is the largest of the three plumes in the East Management Unit. In this plume, the parent compounds, tetrachloroethene and trichloroethene, as well as cis-1,2-dichloroethene, are present downgradient of the source. Vinyl chloride was not detected in the natural attenuation study area. Vertical water-quality profiles indicate that volatile organic compounds are present mainly in the upper part of the surficial aquifer. Plumes of fuel hydrocarbon constituents were not detected in the natural attenuation study area. Volatile organic compounds were present at concentrations above detection limits in 6 of 14 samples collected from the aquifer underlying the bed of Pipe Elm Branch and the drainage ditch adjacent to Fire Training Area Three, indicating that the plumes migrating from Fire Training Area Three and the Receiver Station and Liquid Waste Disposal Landfills are reaching these ground-water discharge areas. In contrast, sampling results indicated that the plume from the Rubble Area Landfill does not reach these ground-water discharge areas. Trichloroethene was present above detection limits in one of four surface-water samples collected from Pipe Elm Branch and the drainage ditch adjacent to Fire Training Area Three. The trichloroethene concentration is below applicable Delaware Department of Natural Resources and Environmental Control surface-water-quality standards for human health. An assessment of chlorinated-solvent mass loss in the plume migrating from the Receiver Station and Liquid Waste Disposal Landfills indicates that tetrachloroethene and trichloroethene mass loss downgradient of the source is negligible. Cis-1,2-dichloroethene, however, appears to biodegrade by an unidentified reaction in the plume. Plan-view maps of the plume migrating from the Receiver Station and Liquid Waste Disposal Landfills indicate that tetrachloroethene, trichloroethene, and cis-1,2-dichloroethene may migrate off Dover Air Force Base property approximately 1,500 f

Demersal fish assemblages of the northeastern Chukchi Sea, Alaska

USGS Publications Warehouse

Barber, W.E.; Smith, R.L.; Vallarino, M.; Meyer, R.M.

1997-01-01

We documented the distribution and abundance of demersal fishes in the northeastern Chukchi Sea, Alaska, in 1990 and 1991, and described 1990 demersal fish assemblages and their relationship to general oceanographic features in the area. We collected samples using an otter trawl at 48 stations in 1990 and 16 in 1991, and we identified a total of 66 species in 14 families. Gadids made up 83% and 69% of the abundance in 1990 and 1991, respectively. Cottids, pleuronectids, and zoarcids together made up 15% of the species in 1990, 28% in 1991. The number of species, species diversity (H), and evenness (V') generally were greater inshore than offshore and greater in the south than in the north. There were significant differences in ranks of species, species diversity, and evenness at 3 of 8 stations sampled beth years. From data collected in 1990, 3 nearshore and 3 offshore station groupings were defined. The northern offshore assemblages had the fewest species, lowest diversity and evenness, and least abundance, whereas two southern assemblages had the most species, highest diversity and evenness, and greatest abundance. We determined that bottom salinity and percent gravel were probably the primary factors influencing assemblage arrangement.

Mapping underwater sound noise and assessing its sources by using a self-organizing maps method.

PubMed

Rako, Nikolina; Vilibić, Ivica; Mihanović, Hrvoje

2013-03-01

This study aims to provide an objective mapping of the underwater noise and its sources over an Adriatic coastal marine habitat by applying the self-organizing maps (SOM) method. Systematic sampling of sea ambient noise (SAN) was carried out at ten predefined acoustic stations between 2007 and 2009. Analyses of noise levels were performed for 1/3 octave band standard centered frequencies in terms of instantaneous sound pressure levels averaged over 300 s to calculate the equivalent continuous sound pressure levels. Data on vessels' presence, type, and distance from the monitoring stations were also collected at each acoustic station during the acoustic sampling. Altogether 69 noise surveys were introduced to the SOM predefined 2 × 2 array. The overall results of the analysis distinguished two dominant underwater soundscapes, associating them mainly to the seasonal changes in the nautical tourism and fishing activities within the study area and to the wind and wave action. The analysis identified recreational vessels as the dominant anthropogenic source of underwater noise, particularly during the tourist season. The method demonstrated to be an efficient tool in predicting the SAN levels based on the vessel distribution, indicating also the possibility of its wider implication for marine conservation.

Reevaluation of air surveillance station siting

DOE Office of Scientific and Technical Information (OSTI.GOV)

Abbott, K.; Jannik, T.

2016-07-06

DOE Technical Standard HDBK-1216-2015 (DOE 2015) recommends evaluating air-monitoring station placement using the analytical method developed by Waite. The technique utilizes wind rose and population distribution data in order to determine a weighting factor for each directional sector surrounding a nuclear facility. Based on the available resources (number of stations) and a scaling factor, this weighting factor is used to determine the number of stations recommended to be placed in each sector considered. An assessment utilizing this method was performed in 2003 to evaluate the effectiveness of the existing SRS air-monitoring program. The resulting recommended distribution of air-monitoring stations wasmore » then compared to that of the existing site perimeter surveillance program. The assessment demonstrated that the distribution of air-monitoring stations at the time generally agreed with the results obtained using the Waite method; however, at the time new stations were established in Barnwell and in Williston in order to meet requirements of DOE guidance document EH-0173T.« less

GIS-based assessment of cancer risk due to benzene in Tehran ambient air.

PubMed

Atabi, Farideh; Mirzahosseini, Seyed Alireza Hajiseyed

2013-10-01

The present study aimed to assess the risk of cancer due to benzene in the ambient air of gas stations and traffic zones in the north of Tehran. The cancer risk was estimated using the population distribution data for benzene levels and the unit risk for benzene proposed by the United States Environmental Protection Agency (US EPA). Sixteen sampling locations were monitored, once every week, during 5 April 2010 to 25 March 2011. The results showed that the mean annual benzene concentration was 14.51±3.17 parts per billion (ppb) for traffic zones and 29.01±1.32 ppb for outside gas stations. The risk calculated was 1026×10(-6) for gas station 27 and 955×10(-6) for gas station 139. According to our results, the annual benzene level in Tehran ambient air is 2 to 20 times higher than the respective value specified in International Standard (1.56 ppb). Moreover, the results showed a notable increase of cancer risks, ranging from 10% to 56%, for the vicinity population close to the gas stations in comparison to the vicinity population in the traffic zones.

Automation of the space station core module power management and distribution system

NASA Technical Reports Server (NTRS)

Weeks, David J.

1988-01-01

Under the Advanced Development Program for Space Station, Marshall Space Flight Center has been developing advanced automation applications for the Power Management and Distribution (PMAD) system inside the Space Station modules for the past three years. The Space Station Module Power Management and Distribution System (SSM/PMAD) test bed features three artificial intelligence (AI) systems coupled with conventional automation software functioning in an autonomous or closed-loop fashion. The AI systems in the test bed include a baseline scheduler/dynamic rescheduler (LES), a load shedding management system (LPLMS), and a fault recovery and management expert system (FRAMES). This test bed will be part of the NASA Systems Autonomy Demonstration for 1990 featuring cooperating expert systems in various Space Station subsystem test beds. It is concluded that advanced automation technology involving AI approaches is sufficiently mature to begin applying the technology to current and planned spacecraft applications including the Space Station.

Distribution of the Fukushima-derived radionuclides in seawater in the Pacific off the coast of Miyagi, Fukushima, and Ibaraki Prefectures, Japan

NASA Astrophysics Data System (ADS)

Oikawa, S.; Takata, H.; Watabe, T.; Misonoo, J.; Kusakabe, M.

2013-07-01

The activities of artificial radionuclides in seawater samples collected off the coast of Miyagi, Fukushima, and Ibaraki Prefectures were measured as part of a monitoring program initiated by the Japanese Ministry of Education, Sports, Science and Technology immediately after the Fukushima Dai-ichi Nuclear Power Plant accident. The spatial and temporal distributions of those activities are summarized herein. The activities of strontium-90, iodine-131, cesium-134 and -137 (i.e. 90Sr, 131I, 134Cs, and 137Cs) derived from the accident were detected in seawater samples taken from areas of the coastal ocean adjacent to the power plant. No 131I was detected in surface waters (≤ 5 m depth) or in intermediate and bottom waters after 30 April 2011. Strontium-90 was found in surface waters collected from a few sampling stations in mid-August 2011 to mid-December 2011. Temporal changes of 90Sr activity in surface waters were evident, although the 90Sr activity at a given time varied widely between sampling stations. The activity of 90Sr in surface waters decreased slowly over time, and by the end of December 2011 had reached background levels recorded before the accident. Radiocesium, 134Cs and 137Cs, was found in seawater samples immediately after the accident. There was a remarkable change in radiocesium activities in surface waters during the first 7 months (March through September 2011) after the accident; the activity reached a maximum in the middle of April and thereafter decreased exponentially with time. Qualitatively, the distribution patterns in surface waters suggested that in early May radiocesium-polluted water was advected northward; some of the water then detached and was transported to the south. Two water cores with high 137Cs activity persisted at least until July 2011. In subsurface waters radiocesium activity was first detected in the beginning of April 2011, and the water masses were characterized by σt (an indicator of density) values of 25.5-26.5. From 9-14 May to 5-16 December 2011, the depths of the water masses increased with time, an indication that deepening of the isopycnal surfaces with time can be an important mechanism for the transport of radiocesium downward in coastal waters. During 4-21 February 2012, the water column became vertically homogeneous, probably because of convective mixing during the winter; the result was nearly constant values of radiocesium activity throughout the water column from the surface to the bottom (~200 m depth) at each station.

Distribution of brominated flame retardants and dechloranes between sediments and benthic fish--A comparison of a freshwater and marine habitat.

PubMed

Sühring, Roxana; Busch, Friederike; Fricke, Nicolai; Kötke, Danijela; Wolschke, Hendrik; Ebinghaus, Ralf

2016-01-15

A total of 53 halogenated flame retardants (HFRs) were analysed in sediments, European eels and dabs from both freshwater and marine sampling stations in the German Bight and the river Elbe. Classic HFRs, such as polybrominated diphenylethers (PBDEs), were the highest concentrated HFRs in eels as well as in most dabs (apart from 1,2,5,6-tetrabromocyclooctane (TBCO)). In sediments, on the other hand, alternate BFRs and especially dechloranes dominated the contamination pattern. Dabs were still found to be statistically representative for the contamination patterns and relative magnitude in sediments from their respective habitats. Contamination patterns in eels seemed to be more driven by the contamination situation in the food chain or historical contamination of their habitat. Unsuspectedly the alternate flame retardant TBCO was found in comparably high concentrations (up to 12 ng g(-1) ww) in dabs from two sampling stations as well as in sediments from these stations (up to 1.2 ng g(-1) dw). It could not be detected in any other analysed fish or sediment samples, indicating a localised contamination source in the area. This study provides information on HFR contamination patterns and behaviour in both marine and freshwater sediments and their potential role as contamination source for benthic fish. Copyright © 2015 Elsevier B.V. All rights reserved.

Summer and winter living coccolithophores in the Yellow Sea and the East China Sea

NASA Astrophysics Data System (ADS)

Gu, X. Y.; Feng, Y. Y.; Jin, S. F.; Jiang, W. S.; Jin, H. Y.; Chen, J. F.; Sun, J.

2013-05-01

To date, very little information on living coccolithophores species composition and distribution, especially the vertical profile has been reported around the world. This paper tries to fill this gap by descripting on living coccolithophores (LCs) distribution in the Yellow Sea and the East China Sea in summer and winter time in detail, and its relationship among enviromental factors by canonical correspondence analysis (CCA). We carried out the investigations on LC distribution in the Yellow Sea and the East China Sea in July and December 2011. 210 samples from different depths were collected from 44 stations in summer and 217 samples were collected from 45 stations in winter. Totally 20 taxa belonging to coccolithophyceae were identified using a polarized microscope at the 1000 × magnification. The dominant species of the two seasons were Gephyrocapsa oceanica, Emiliania huxleyi, Helicosphaera carteri, and Algirosphaera robusta. In summer the abundance of cells and coccoliths ranged 0 ~ 176.40 cells mL-1, and 0 ~ 2144.98 coccoliths mL-1, with the average values of 8.45 cells mL-1, and 265.42 coccoliths mL-1, respectively. And in winter the abundance of cells and coccoliths ranged 0 ~ 71.66 cells mL-1, and 0 ~ 4698.99 coccoliths mL-1, with the average values of 13.91 cells mL-1 and 872.56 coccoliths mL-1 respectively. In summer the LCs in surface layer were mainly observed on the coastal belt and southern part of the survey area. The highest abundance was found at the bloom station. In winter the LCs in surface layer had high value in the continental shelf area of section P. The comparison among section A, section F, section P and section E indicated lower species diversity and less abundance in the Yellow Sea than those of the East China Sea in both seasons. Temperature and the nitrate concentration may be the major environmental factors controlling the distribution and species composition of LCs in the studying area based on CCA.

High-resolution probing of inner core structure with seismic interferometry

NASA Astrophysics Data System (ADS)

Huang, Hsin-Hua; Lin, Fan-Chi; Tsai, Victor C.; Koper, Keith D.

2015-12-01

Increasing complexity of Earth's inner core has been revealed in recent decades as the global distribution of seismic stations has improved. The uneven distribution of earthquakes, however, still causes a biased geographical sampling of the inner core. Recent developments in seismic interferometry, which allow for the retrieval of core-sensitive body waves propagating between two receivers, can significantly improve ray path coverage of the inner core. In this study, we apply such earthquake coda interferometry to 1846 USArray stations deployed across the U.S. from 2004 through 2013. Clear inner core phases PKIKP2 and PKIIKP2 are observed across the entire array. Spatial analysis of the differential travel time residuals between the two phases reveals significant short-wavelength variation and implies the existence of strong structural variability in the deep Earth. A linear N-S trending anomaly across the middle of the U.S. may reflect an asymmetric quasi-hemispherical structure deep within the inner core with boundaries of 99°W and 88°E.

Distribution and Habitat Associations of Billfish and Swordfish Larvae across Mesoscale Features in the Gulf of Mexico

PubMed Central

Rooker, Jay R.; Simms, Jeff R.; Wells, R. J. David; Holt, Scott A.; Holt, G. Joan; Graves, John E.; Furey, Nathan B.

2012-01-01

Ichthyoplankton surveys were conducted in surface waters of the northern Gulf of Mexico (NGoM) over a three-year period (2006–2008) to determine the relative value of this region as early life habitat of sailfish (Istiophorus platypterus), blue marlin (Makaira nigricans), white marlin (Kajikia albida), and swordfish (Xiphias gladius). Sailfish were the dominant billfish collected in summer surveys, and larvae were present at 37.5% of the stations sampled. Blue marlin and white marlin larvae were present at 25.0% and 4.6% of the stations sampled, respectively, while swordfish occurred at 17.2% of the stations. Areas of peak production were detected and maximum density estimates for sailfish (22.09 larvae 1000 m−2) were significantly higher than the three other species: blue marlin (9.62 larvae 1000 m−2), white marlin (5.44 larvae 1000 m−2), and swordfish (4.67 larvae 1000 m−2). The distribution and abundance of billfish and swordfish larvae varied spatially and temporally, and several environmental variables (sea surface temperature, salinity, sea surface height, distance to the Loop Current, current velocity, water depth, and Sargassum biomass) were deemed to be influential variables in generalized additive models (GAMs). Mesoscale features in the NGoM affected the distribution and abundance of billfish and swordfish larvae, with densities typically higher in frontal zones or areas proximal to the Loop Current. Habitat suitability of all four species was strongly linked to physicochemical attributes of the water masses they inhabited, and observed abundance was higher in slope waters with lower sea surface temperature and higher salinity. Our results highlight the value of the NGoM as early life habitat of billfishes and swordfish, and represent valuable baseline data for evaluating anthropogenic effects (i.e., Deepwater Horizon oil spill) on the Atlantic billfish and swordfish populations. PMID:22509277

Distribution and habitat associations of billfish and swordfish larvae across mesoscale features in the Gulf of Mexico.

PubMed

Rooker, Jay R; Simms, Jeff R; Wells, R J David; Holt, Scott A; Holt, G Joan; Graves, John E; Furey, Nathan B

2012-01-01

Ichthyoplankton surveys were conducted in surface waters of the northern Gulf of Mexico (NGoM) over a three-year period (2006-2008) to determine the relative value of this region as early life habitat of sailfish (Istiophorus platypterus), blue marlin (Makaira nigricans), white marlin (Kajikia albida), and swordfish (Xiphias gladius). Sailfish were the dominant billfish collected in summer surveys, and larvae were present at 37.5% of the stations sampled. Blue marlin and white marlin larvae were present at 25.0% and 4.6% of the stations sampled, respectively, while swordfish occurred at 17.2% of the stations. Areas of peak production were detected and maximum density estimates for sailfish (22.09 larvae 1000 m(-2)) were significantly higher than the three other species: blue marlin (9.62 larvae 1000 m(-2)), white marlin (5.44 larvae 1000 m(-2)), and swordfish (4.67 larvae 1000 m(-2)). The distribution and abundance of billfish and swordfish larvae varied spatially and temporally, and several environmental variables (sea surface temperature, salinity, sea surface height, distance to the Loop Current, current velocity, water depth, and Sargassum biomass) were deemed to be influential variables in generalized additive models (GAMs). Mesoscale features in the NGoM affected the distribution and abundance of billfish and swordfish larvae, with densities typically higher in frontal zones or areas proximal to the Loop Current. Habitat suitability of all four species was strongly linked to physicochemical attributes of the water masses they inhabited, and observed abundance was higher in slope waters with lower sea surface temperature and higher salinity. Our results highlight the value of the NGoM as early life habitat of billfishes and swordfish, and represent valuable baseline data for evaluating anthropogenic effects (i.e., Deepwater Horizon oil spill) on the Atlantic billfish and swordfish populations.

Clostridium perfringens in the Environment1

PubMed Central

Matches, Jack R.; Liston, John; Curran, Donald

1974-01-01

Clostridium perfringens was isolated from samples collected in Puget Sound in the state of Washington and areas considered as possible sources of these organisms to Puget Sound. The distribution of C. perfringens in the total Clostridium population was determined for fish gut contents and sediments collected in highly polluted and less polluted areas, sewage samples, freshwater sediments, and soils. The greatest numbers of C. perfringens were obtained from marine sediments collected near the sewage outfall at West Point. Fewer isolates were made from fish collected from less polluted stations, although the number of C. perfringens remained high in sediments from other Puget Sound stations. The proportion of C. perfringens in the total Clostridium populations varied between 56 and 71% for sewage samples and only 0.4 to 4.1% for freshwater sediments and soil samples. Only 25 C. perfringens isolates out of 137 from fish guts, or 18%, were identifiable serologically and these fell into 12 groups. C. perfringens were fed to fish and the fish were sacrificed after varying lengths of time. The number of C. perfringens increased slightly in the gut during the first 24 h and then the numbers decreased rapidly for the next 120 h. PMID:4371684

High Resolution Observations of Dissolved Iron Distribution Along a Coastal Offshore Transect in the Eastern North Atlantic.

NASA Astrophysics Data System (ADS)

Blain, S.; Laes, A.; Laan, P.; Achterberg, E.; de Baar, H.

2002-12-01

In order to better understand and quantify the inputs of iron from below in the water column a detailed section from the coast to offshore has been studied in the eastern North Atlantic. The section, extended from 47°36 58 N, 4°14 51 W (depth 96 m) to 46°00 00 N, 8°00 00 W (depth 4912 m). The cruise took place in March 2002, on board R/V Pelagia, as part of the European Union project IRONAGES. Fifteen stations have been sampled for dissolved iron (DFe) and nutrients analysis. Go Flo bottles mounted on a kevlar cable were used for clean seawater sampling in the water column. A torpedo fish and trace metal clean bellows pump were used for surface sampling. Sample were filtered on-line through an 0.2 μm cartridge. The DFe concentrations were measured onboard using a FIA method with on line preconcentration (8-HQ resin) and chemiluminescence detection (mean blank = 28 pM, mean limit of detection= 39 pM). The coastal stations over the shelf showed the highest concentrations of DFe. In this part of the transect, the concentration decreased from the surface to the bottom. Maxima (1-2.4 nM) were associated with increase in turbidity demonstrating the DFe inputs associated with re-suspended sediments and/or pore waters. In the eastern part of the transect, water of the Loire river has been identified has a source of iron. Close to the shelf break the two dimensional iron distribution became more complex. A tidal front, internal waves and slope currents created a patchy distribution of DFe. Evertheless the input from below was always observable at depth between 500 and 1200 m. Finally, in the western part of the transect, off the plateau, the concentration of DFe was strongly correlated with the occurrence of different water masses (see abstract by A. Laës).

Fully probabilistic seismic source inversion - Part 2: Modelling errors and station covariances

NASA Astrophysics Data System (ADS)

Stähler, Simon C.; Sigloch, Karin

2016-11-01

Seismic source inversion, a central task in seismology, is concerned with the estimation of earthquake source parameters and their uncertainties. Estimating uncertainties is particularly challenging because source inversion is a non-linear problem. In a companion paper, Stähler and Sigloch (2014) developed a method of fully Bayesian inference for source parameters, based on measurements of waveform cross-correlation between broadband, teleseismic body-wave observations and their modelled counterparts. This approach yields not only depth and moment tensor estimates but also source time functions. A prerequisite for Bayesian inference is the proper characterisation of the noise afflicting the measurements, a problem we address here. We show that, for realistic broadband body-wave seismograms, the systematic error due to an incomplete physical model affects waveform misfits more strongly than random, ambient background noise. In this situation, the waveform cross-correlation coefficient CC, or rather its decorrelation D = 1 - CC, performs more robustly as a misfit criterion than ℓp norms, more commonly used as sample-by-sample measures of misfit based on distances between individual time samples. From a set of over 900 user-supervised, deterministic earthquake source solutions treated as a quality-controlled reference, we derive the noise distribution on signal decorrelation D = 1 - CC of the broadband seismogram fits between observed and modelled waveforms. The noise on D is found to approximately follow a log-normal distribution, a fortunate fact that readily accommodates the formulation of an empirical likelihood function for D for our multivariate problem. The first and second moments of this multivariate distribution are shown to depend mostly on the signal-to-noise ratio (SNR) of the CC measurements and on the back-azimuthal distances of seismic stations. By identifying and quantifying this likelihood function, we make D and thus waveform cross-correlation measurements usable for fully probabilistic sampling strategies, in source inversion and related applications such as seismic tomography.

Surface-water-quality assessment of the upper Illinois River Basin in Illinois, Indiana, and Wisconsin; pesticides and other synthetic organic compounds in water, sediment, and biota, 1975-90

USGS Publications Warehouse

Sullivan, Daniel J.; Stinson, Troy W.; Crawford, J. Kent; Schmidt, Arthur R.; Colman, John A.

1998-01-01

The distribution of pesticides and other synthetic organic compounds in water, sediment, and biota in the upper Illinois River Basin in Illinois, Indiana, and Wisconsin was examined from 1987 through 1990 as part of the pilot National Water-Quality Assesssment Program conducted by the U.S. Geological Survey. Historical data for water and sediment collected from 1975 through 1986 were similar to data collected from 1987 through 1990. Some compounds were detected in concentrations that exceed U.S. Environmental Protection Agency water-quality criteria. Results from pesticide sampling at four stations in 1988 and 1989 identified several agricultural pesticides that were detected more frequently and at higher concentrations in urban areas than in agricultural areas. Results from herbicide sampling at 17 stations in the Kankakee and Iroquois River Basins in 1990 indicated that atrazine concentrations exceeded the U.S. Environmental Protection Agency's maximum contaminant level for drinking water during runoff periods. Results from sampling for volatile and semivolatile organic compounds in water indicate that, with one exception, all stations at which more than one compound was detected were within 2 miles downstream from the nearest point source. Detections at two stations in the Chicago urban area accounted for 37 percent of the total number of detections. Concentrations of tetrachloroethylene, trichloroethylene, and 1,2-dichlorethane from stations in the Des Plaines River Basin exceeded the U.S. Environmental Protection Agency's maximum contaminant level for drinking water in one and two samples from the two stations in the Chicago area. Phenols and pentachlorophenols were detected most frequently in the Des Plaines River Basin where point-source discharges were common. Phenol concentrations were significantly different among the Des Plaines, Kankakee, and Fox River Basins. Phenols and pentachlorophenols never exceeded the general use and secondary contact standards. Results from a 1989 synoptic survey of semivolatile organic compounds in sediment indicate that these compounds were detected most frequently at sites in the Chicago urban area. Of the 17 stations at which 10 or more compounds were detected, 14 were located in the Des Plaines River subbasin, and 1 was on the Illinois River mainstem. As was the case with organic compounds in water, each of these sites was located within 2 miles downstream from point sources. Biota samples were collected and analyzed for organochlorines and polynuclear aromatic hydrocarbons in 1989 and 1990. The most commonly detected compound in both years was p,p'-DDE. National Academy of Science recommendations for chlordane and dieldrin for protection of predators were exceeded in 19 and 10 samples, respectively, when the 1989 and 1990 data were combined. In the nine fish-fillet samples collected in 1989, concentrations exceeded U.S. Environmental Protection Agency fish-tissue criteria in nine fillets for p,p'-DDE and five fillets for dieldrin.

Tidal river sediments in the Washington, D.C. area. 11. Distribution and sources of organic containmants

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wade, T.L.; Velinsky, D.J.; Reinharz, E.

1994-06-01

Concentrations of aliphatic, aromatic, and chlorinated hydrocarbons were determined from 33 surface-sediment samples taken from the Tidal Basin, Washington Ship Channel, and the Anacostia and Potomac rivers in Washington, D.C. In conjunction with these samples, selected storm sewers and outfalls also were sampled to help elucidate general sources of contamination to the area. All of the sediments contained detectable concentrations of aliphatic and aromatic hydrocarbons, DDT (total dichlorodiphenytrichloroethande), DDE (dichlorodiphenyldichloroethene), DDD (dichlorodiphenyldichloroethane), PCBx (total polychlorinated biphenyls) and total chlordanes (oxy-, {alpha}-, and {gamma}-chlordane and cis + trans-nonachlor). Sediment concentrations of most contaminants were highest in the Anacostia River just downstreammore » of the Washington Navy Yard, except for total chlordane, which appeared to have upstream sources in addition to storm and combined sewer runoff. This area has the highest number of storm and combined sewer outfalls in the river. Potomac River stations had lower concentrations than other stations. Polycyclic aromatic hydrocarbons, saturated hydrocarbons, and the unresolved complex mixture (UCM) distributions reflect mixtures of combustion products and direct discharges of petroleum products. Sources of PCBs appear to be related to specific outfalls, while hydrocarbon inputs, especially PAHs, are diffuse, and may be related to street runoff. This study indicates that in large urban areas, nonpoint sources deliver substantial amounts of contaminants to ecosystems through storm and combined sewer systems, and control of these inputs must be addressed. 33 refs., 6 figs., 3 tabs.« less

The influence of wetting dynamics on the residual air distribution

NASA Astrophysics Data System (ADS)

Sacha, J.; Snehota, M.; Trtik, P.; Vontobel, P.

2016-12-01

The amount and distribution of the residual air during the infiltration into a porous soil system has a strong influence on the infiltration rate. Concurrently, the amount of residual air is dependent on the wetting dynamics. In the presented study, two experiments were conducted on the same sample. The first experiment was performed under the constant water level condition (CWL) and the second under the constant water flux condition (CWF) at the top of the sample. The sample that composed of coarse and medium coarse fractions of sand and fine porous ceramics was packed into the quartz glass columns of the inner diameter of 29 mm. The coarse sand represented a highly conductive region connected from the top to the bottom of the sample with the exception of three low (2-3 mm) separation layers made up of the medium coarse sand. Three discs of fine ceramic formed slow flow regions. Infiltration experiments were monitored by neutron radiography on two different beamlines to produce two-dimensional (2D) projections. The CWL experiment was monitored by NEUTRA station with an acquisition time of 16 seconds per projection and the CWF experiment was visualized at BOA station with an acquisition time of 0.25 seconds per projection. Both stations are located at the Paul Scherrer Institut, Switzerland. The acquired radiograms of the dry sample were subtracted from all subsequent radiograms to determine the water thickness in projections. From series of corrected radiograms taken at the different angles three-dimensional (3D) image was reconstructed for steady state part of the experiment CWL and for entire experiment CWF. Then the series of 3D images mapped the wetting of the porous system over the corresponding phase of infiltration process. The results showed a faster steady state infiltration rate during the CWL. In this case, the air was mostly pushed out from the sample by moving wetting front. On the contrary, during the CWF the water infiltrated into the fine ceramics first and then into the medium coarse sand attracted by stronger capillary forces in comparison to the coarse sand. Due to this effect a significant amount of air was trapped in preferential pathways, and consequently blocking the water flow. The presence of medium coarse sand regions had a crucial impact on the water flow and amount of air trapping.

On the Retrieval of Geocenter Motion from Gravity Data

NASA Astrophysics Data System (ADS)

Rosat, S.; Mémin, A.; Boy, J. P.; Rogister, Y. J. G.

2017-12-01

The center of mass of the whole Earth, the so-called geocenter, is moving with respect to the Center of Mass of the solid Earth because of the loading exerted by the Earth's fluid layers on the solid crust. Space geodetic techniques tying satellites and ground stations (e.g. GNSS, SLR and DORIS) have been widely employed to estimate the geocenter motion. Harmonic degree-1 variations of the gravity field are associated to the geocenter displacement. We show that ground records of time-varying gravity from Superconducting Gravimeters (SGs) can be used to constrain the geocenter motion. Two major difficulties have to be tackled: (1) the sensitivity of surface gravimetric measurements to local mass changes, and in particular hydrological and atmospheric variabilities; (2) the spatial aliasing (spectral leakage) of spherical harmonic degrees higher than 1 induced by the under-sampling of station distribution. The largest gravity variations can be removed from the SG data by subtracting solid and oceanic tides as well as atmospheric and hydrologic effects using global models. However some hydrological signal may still remain. Since surface water content is well-modelled using GRACE observations, we investigate how the spatial aliasing in SG data can be reduced by employing GRACE solutions when retrieving geocenter motion. We show synthetic simulations using complete surface loading models together with GRACE solutions computed at SG stations. In order to retrieve the degree-one gravity variations that are associated with the geocenter motion, we use a multi-station stacking method that performs better than a classical spherical harmonic stacking when the station distribution is inhomogeneous. We also test the influence of the network configuration on the estimate of the geocenter motion. An inversion using SG and GRACE observations is finally presented and the results are compared with previous geocenter estimates.

Pollution Characteristics and Health Risk Assessment of Airborne Heavy Metals Collected from Beijing Bus Stations

PubMed Central

Zheng, Xiaoxia; Zhao, Wenji; Yan, Xing; Shu, Tongtong; Xiong, Qiulin; Chen, Fantao

2015-01-01

Airborne dust, which contains high levels of toxic metals, is recognized as one of the most harmful environment component. The purpose of this study was to evaluate heavy metals pollution in dustfall from bus stations in Beijing, and to perform a risk assessment analysis for adult passengers. The concentrations of Cd, Co, Cr, Cu, Mo, Ni, Pb, V and Zn were determined by inductively coupled plasma mass spectroscopy (ICP-MS). The spatial distribution, pollution level and potential health risk of heavy metals were analyzed by Geographic Information System (GIS) mapping technology, geo-accumulation index and health risk assessment model, respectively. The results indicate that dust samples have elevated metal concentrations, especially for Cd, Cu, Pb and Zn. The nine metals can be divided into two categories in terms of spatial distribution and pollution level. Cd, Cr, Cu, Mo, Pb and Zn reach contaminated level and have similar spatial patterns with hotspots distributed within the Fifth Ring Road. While the hot spot areas of Co and V are always out of the Fifth Ring Road. Health risk assessment shows that both carcinogenic and non-carcinogenic risks of selected metals were within the safe range. PMID:26287229

Pollution Characteristics and Health Risk Assessment of Airborne Heavy Metals Collected from Beijing Bus Stations.

PubMed

Zheng, Xiaoxia; Zhao, Wenji; Yan, Xing; Shu, Tongtong; Xiong, Qiulin; Chen, Fantao

2015-08-17

Airborne dust, which contains high levels of toxic metals, is recognized as one of the most harmful environment component. The purpose of this study was to evaluate heavy metals pollution in dustfall from bus stations in Beijing, and to perform a risk assessment analysis for adult passengers. The concentrations of Cd, Co, Cr, Cu, Mo, Ni, Pb, V and Zn were determined by inductively coupled plasma mass spectroscopy (ICP-MS). The spatial distribution, pollution level and potential health risk of heavy metals were analyzed by Geographic Information System (GIS) mapping technology, geo-accumulation index and health risk assessment model, respectively. The results indicate that dust samples have elevated metal concentrations, especially for Cd, Cu, Pb and Zn. The nine metals can be divided into two categories in terms of spatial distribution and pollution level. Cd, Cr, Cu, Mo, Pb and Zn reach contaminated level and have similar spatial patterns with hotspots distributed within the Fifth Ring Road. While the hot spot areas of Co and V are always out of the Fifth Ring Road. Health risk assessment shows that both carcinogenic and non-carcinogenic risks of selected metals were within the safe range.

Prominent artificial radionuclide activity in the environment of coastal Karnataka on the southwest coast of India.

PubMed

Narayana, Y; Somashekarappa, H M; Karunakara, N; Avadhani, D N; Mahesh, H M; Siddappa, K

2000-09-01

Studies on radiation level and radionuclide distribution in the environment of coastal Karnataka were undertaken to provide baseline data for the future assessment of the impact of the nuclear and thermal power stations that are being set up in the region and to understand the behaviour of radionuclides in the environment. As part of the programme the concentrations of two important artificial radionuclides, namely 90Sr and 137Cs, have been measured in a number of environmental samples. The concentration of 90Sr is very low in most of the samples. Among the samples analysed for the concentration of 137Cs, soil samples showed elevated levels of activity in some sampling stations. Among the vegetables, brinjal (Solanum melongena. L) showed considerable activity. The internal dose due to intake of 90Sr through diet was 0.42 microSv year(-1) for the vegetarian population and 0.32 microSv year(-1) for the non-vegetarian population. The internal dose due to dietary intake of 137Cs was found to be 0.34 microSv year(-1) and 0.26 microSv year(-1) respectively for the vegetarian and non-vegetarian population. The results are discussed in the light of the literature values reported for other environs of India and abroad and appropriate inferences are drawn.

Spatial distribution and ecotoxicity of petroleum hydrocarbons in sediments from the Galicia continental shelf (NW Spain) after the Prestige oil spill.

PubMed

Franco, M A; Viñas, L; Soriano, J A; de Armas, D; González, J J; Beiras, R; Salas, N; Bayona, J M; Albaigés, J

2006-01-01

The distribution of aliphatic and aromatic hydrocarbons was determined in surface sediments collected at 36 stations along the Galicia continental shelf (NW Spain), following the Prestige oil spill. Sampling was performed in December 2002, just after the accident, and in February and September 2003. Concentrations of PAHs (summation operator 13 parent components) were in the range of 0.9-422 microg/kgdw, the highest values being close to coastal urban areas (e.g. Pontevedra and A Coruña), whereas in the stations of the area most heavily impacted by the spill (off Costa da Morte) concentrations were in the range of 14.8-89.6 microg/kgdw, with a certain predominance of alkylated compounds, which may suggest a mixture of petrogenic and pyrolytic sources. The detailed study of petrogenic molecular markers (e.g. steranes and triterpanes) showed the occurrence of an old (weathered) petrogenic chronic pollution in the shelf sediments but not of the Prestige oil, with the possible exception of few stations in the area of Costa da Morte. This was attributed to the heavy nature of the spilled oil that was barely dispersed in the water column and mainly stranded on the coast or sedimented in the form of oil patches. The addition of increasing amounts of fuel oil to a representative sediment sample showed that the molecular indices were indicative of the presence of the Prestige oil when the amount was above 1g/kg of sediment. The toxicity of selected samples (showing the higher PAH concentrations) was tested using the bivalve embryogenesis bioassay. Embryogenesis success reached high values in all cases (80-88%, with 86% in the control), indicating a lack of toxicity in the sediments and supporting the conclusion that the patchiness of the fuel eventually reaching the seafloor reduced its impact on the benthic communities of the Galician shelf.

The summertime plankton community at South Georgia (Southern Ocean): Comparing the historical (1926/1927) and modern (post 1995) records

NASA Astrophysics Data System (ADS)

Ward, Peter; Meredith, Michael P.; Whitehouse, Mick J.; Rothery, Peter

2008-09-01

The earliest comprehensive plankton sampling programme in the Southern Ocean was undertaken during the early part of last century by Discovery Investigations to gain a greater scientific understanding of whale stocks and their summer feeding grounds. An initial survey was carried out around South Georgia during December 1926 and January 1927 to describe the distribution of plankton during the summer, and to serve as a baseline against which to compare future surveys. We have reanalysed phytoplankton and zooplankton data from this survey and elucidated patterns of community distribution and compared them with our recent understanding of the ecosystem based on contemporary data. Analysis of Discovery data identified five groups of stations with characteristic phytoplankton communities which were almost entirely consistent with the original analysis conducted by [Hardy A.C., Gunther, E.R., 1935. The plankton of the South Georgia whaling grounds and adjacent waters 1926-1927. Discovery Report 11, 1-456]. Major groupings were located at the western end of the island and over the northern shelf where Corethron spp. were dominant, and to the south and east where a more diverse flora included high abundances of Nitzschia seriata. Major zooplankton-station groupings were located over the inner shelf which was characterised by a high abundance of Drepanopus forcipatus and in oceanic water >500 m deep that were dominated by Foraminifera, Oithona spp., Ctenocalanus vanus, and Calanoides acutus. Stations along the middle and outer shelf regions to the north and west, were characterised by low overall abundance. There was some evidence that groupings of stations to the north of the island originated in different water masses on either side of the Southern Antarctic Circumpolar Current Front, the major frontal system in the deep ocean close to South Georgia. However, transect lines during 1926/1927 did not extend far enough offshore to sample this frontal region adequately. Interannual variability of zooplankton abundance was assessed from stations which were sampled repeatedly during seven recent British Antarctic Survey cruises (1995-2005) to the region and following taxonomic harmonization and numerical standardization (ind. m -3), a subset of 45 taxonomic categories of zooplankton (species and higher taxa) from 1926/1927, were compared with similar data obtained during the BAS cruises using a linear model. Initially comparisons were restricted to BAS stations that lay within 40 km of Discovery stations although a comparison was also made using all available data. Despite low abundance values in 1926/1927, in neither comparison did Discovery data differ significantly from BAS data. Calculation of the percentage similarity index across cruises did not reveal any systematic differences in species composition between 1926 and 1927 and the present. In the light of ocean warming trends, the existence of more subtle changes in species composition is not ruled out, but an absence of finely resolved time-series data make this impossible to determine.

Evaluation of the streamflow-gaging network of Alaska in providing regional streamflow information

USGS Publications Warehouse

Brabets, Timothy P.

1996-01-01

In 1906, the U.S. Geological Survey (USGS) began operating a network of streamflow-gaging stations in Alaska. The primary purpose of the streamflow- gaging network has been to provide peak flow, average flow, and low-flow characteristics to a variety of users. In 1993, the USGS began a study to evaluate the current network of 78 stations. The objectives of this study were to determine the adequacy of the existing network in predicting selected regional flow characteristics and to determine if providing additional streamflow-gaging stations could improve the network's ability to predict these characteristics. Alaska was divided into six distinct hydrologic regions: Arctic, Northwest, Southcentral, Southeast, Southwest, and Yukon. For each region, historical and current streamflow data were compiled. In Arctic, Northwest, and Southwest Alaska, insufficient data were available to develop regional regression equations. In these areas, proposed locations of streamflow-gaging stations were selected by using clustering techniques to define similar areas within a region and by spatial visual analysis using the precipitation, physiographic, and hydrologic unit maps of Alaska. Sufficient data existed in Southcentral and Southeast Alaska to use generalized least squares (GLS) procedures to develop regional regression equations to estimate the 50-year peak flow, annual average flow, and a low-flow statistic. GLS procedures were also used for Yukon Alaska but the results should be used with caution because the data do not have an adequate spatial distribution. Network analysis procedures were used for the Southcentral, Southeast, and Yukon regions. Network analysis indicates the reduction in the sampling error of the regional regression equation that can be obtained given different scenarios. For Alaska, a 10-year planning period was used. One scenario showed the results of continuing the current network with no additional gaging stations and another scenario showed the results of adding gaging stations to the network. With the exception of the annual average discharge equation for Southeast Alaska, by adding gaging stations in all three regions, the sampling error was reduced to a greater extent than by not adding gaging stations. The proposed streamflow-gaging network for Alaska consists of 308 gaging stations, of which 32 are designated as index stations. If the proposed network can not be implemented in its entirety, then a lesser cost alternative would be to establish the index stations and to implement the network for a particular region.

Variation in the diel vertical distributions of larvae and transforming stages of oceanic fishes across the tropical and equatorial Atlantic

NASA Astrophysics Data System (ADS)

Olivar, M. Pilar; Contreras, Tabit; Hulley, P. Alexander; Emelianov, Mikhail; López-Pérez, Cristina; Tuset, Víctor; Castellón, Arturo

2018-01-01

The vertical distributions of early developmental stages of oceanic fishes were investigated across the tropical and equatorial Atlantic, from oligotrophic waters close to the Brazilian coast to more productive waters close to the Mauritanian Upwelling Region. Stratification of the water column was observed throughout the study region. Fishes were caught with a MOCNESS-1 net with mouth area of 1 m2 at 11 stations. Each station was sampled both during the day and at night within a single 24-h period. The investigation covered both larvae and transforming stages from the surface to 800 m depth. Distribution patterns were analysed, and weighted mean depths for the larvae and transforming stages of each species were calculated for day and night conditions. Forty-seven different species were found. The highest number of species occurred in the three stations south of Cape Verde Islands, characterized by a mixture of South Atlantic Central Water (SACW) and Eastern North Atlantic Central Water (ENACW). There was a marked drop in species richness in the three stations closer to the African upwelling, dominated by ENACW. The highest abundances occurred in the families Myctophidae, Sternoptychidae, Gonostomatidae and Phosichthyidae. Day and night vertical distributions of larvae and transforming stages showed contrasting patterns, both in the depths of the main concentration layers in the water column, and in the diel migration patterns (where these were observed). Larvae generally showed a preference for the upper mixed layer (ca. 0-50 m) and upper thermocline (ca. 50-100 m), except for sternoptychids, which were also abundant in the lower thermocline layer (100-200 m) and even extended into the mesopelagic zone (down to 500 m). Transforming stages showed a more widespread distribution, with main concentrations in the mesopelagic zone (200-800 m). Larvae showed peak concentrations in the more illuminated and zooplankton-rich upper mixed layers during the day and a wider distribution through the upper 100 m during the night. For most species, transforming stages were concentrated in the mesopelagic layers both day and night, although in some species (Diaphus cf. vanhoeffeni and Vinciguerria nimbaria), the transforming stages displayed vertical migration into the upper 100 m at night, in a manner similar to their adult stages.

Quantum key distribution using card, base station and trusted authority

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nordholt, Jane E.; Hughes, Richard John; Newell, Raymond Thorson

Techniques and tools for quantum key distribution ("QKD") between a quantum communication ("QC") card, base station and trusted authority are described herein. In example implementations, a QC card contains a miniaturized QC transmitter and couples with a base station. The base station provides a network connection with the trusted authority and can also provide electric power to the QC card. When coupled to the base station, after authentication by the trusted authority, the QC card acquires keys through QKD with a trust authority. The keys can be used to set up secure communication, for authentication, for access control, or formore » other purposes. The QC card can be implemented as part of a smart phone or other mobile computing device, or the QC card can be used as a fillgun for distribution of the keys.« less

Quantum key distribution using card, base station and trusted authority

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nordholt, Jane Elizabeth; Hughes, Richard John; Newell, Raymond Thorson

Techniques and tools for quantum key distribution ("QKD") between a quantum communication ("QC") card, base station and trusted authority are described herein. In example implementations, a QC card contains a miniaturized QC transmitter and couples with a base station. The base station provides a network connection with the trusted authority and can also provide electric power to the QC card. When coupled to the base station, after authentication by the trusted authority, the QC card acquires keys through QKD with a trusted authority. The keys can be used to set up secure communication, for authentication, for access control, or formore » other purposes. The QC card can be implemented as part of a smart phone or other mobile computing device, or the QC card can be used as a fillgun for distribution of the keys.« less

47 CFR 74.482 - Station identification.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 47 Telecommunication 4 2010-10-01 2010-10-01 false Station identification. 74.482 Section 74.482..., AUXILIARY, SPECIAL BROADCAST AND OTHER PROGRAM DISTRIBUTIONAL SERVICES Remote Pickup Broadcast Stations § 74.482 Station identification. (a) Each remote pickup broadcast station shall be identified by the...

47 CFR 74.582 - Station identification.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 47 Telecommunication 4 2010-10-01 2010-10-01 false Station identification. 74.582 Section 74.582..., AUXILIARY, SPECIAL BROADCAST AND OTHER PROGRAM DISTRIBUTIONAL SERVICES Aural Broadcast Auxiliary Stations § 74.582 Station identification. (a) Each aural broadcast STL or intercity relay station, when...

47 CFR 74.433 - Temporary authorizations.

Code of Federal Regulations, 2014 CFR

2014-10-01

... identification number of the associated broadcast station or stations, call letters of remote pickup station (if..., AUXILIARY, SPECIAL BROADCAST AND OTHER PROGRAM DISTRIBUTIONAL SERVICES Remote Pickup Broadcast Stations § 74.433 Temporary authorizations. (a) Special temporary authority may be granted for remote pickup station...

47 CFR 74.433 - Temporary authorizations.

Code of Federal Regulations, 2012 CFR

2012-10-01

... identification number of the associated broadcast station or stations, call letters of remote pickup station (if..., AUXILIARY, SPECIAL BROADCAST AND OTHER PROGRAM DISTRIBUTIONAL SERVICES Remote Pickup Broadcast Stations § 74.433 Temporary authorizations. (a) Special temporary authority may be granted for remote pickup station...

47 CFR 74.433 - Temporary authorizations.

Code of Federal Regulations, 2011 CFR

2011-10-01

... identification number of the associated broadcast station or stations, call letters of remote pickup station (if..., AUXILIARY, SPECIAL BROADCAST AND OTHER PROGRAM DISTRIBUTIONAL SERVICES Remote Pickup Broadcast Stations § 74.433 Temporary authorizations. (a) Special temporary authority may be granted for remote pickup station...

47 CFR 74.433 - Temporary authorizations.

Code of Federal Regulations, 2013 CFR

2013-10-01

... identification number of the associated broadcast station or stations, call letters of remote pickup station (if..., AUXILIARY, SPECIAL BROADCAST AND OTHER PROGRAM DISTRIBUTIONAL SERVICES Remote Pickup Broadcast Stations § 74.433 Temporary authorizations. (a) Special temporary authority may be granted for remote pickup station...

SOARCA Peach Bottom Atomic Power Station Long-Term Station Blackout Uncertainty Analysis: Convergence of the Uncertainty Results

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bixler, Nathan E.; Osborn, Douglas M.; Sallaberry, Cedric Jean-Marie

2014-02-01

This paper describes the convergence of MELCOR Accident Consequence Code System, Version 2 (MACCS2) probabilistic results of offsite consequences for the uncertainty analysis of the State-of-the-Art Reactor Consequence Analyses (SOARCA) unmitigated long-term station blackout scenario at the Peach Bottom Atomic Power Station. The consequence metrics evaluated are individual latent-cancer fatality (LCF) risk and individual early fatality risk. Consequence results are presented as conditional risk (i.e., assuming the accident occurs, risk per event) to individuals of the public as a result of the accident. In order to verify convergence for this uncertainty analysis, as recommended by the Nuclear Regulatory Commission’s Advisorymore » Committee on Reactor Safeguards, a ‘high’ source term from the original population of Monte Carlo runs has been selected to be used for: (1) a study of the distribution of consequence results stemming solely from epistemic uncertainty in the MACCS2 parameters (i.e., separating the effect from the source term uncertainty), and (2) a comparison between Simple Random Sampling (SRS) and Latin Hypercube Sampling (LHS) in order to validate the original results obtained with LHS. Three replicates (each using a different random seed) of size 1,000 each using LHS and another set of three replicates of size 1,000 using SRS are analyzed. The results show that the LCF risk results are well converged with either LHS or SRS sampling. The early fatality risk results are less well converged at radial distances beyond 2 miles, and this is expected due to the sparse data (predominance of “zero” results).« less

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hunter, C.; Simpson, J.; Kovats, Z.

Sediments from Soda Creek were evaluated using the Sediment Quality Triad as part of investigations being conducted at the Monsanto Company plant in Soda Springs, Idaho. Information collected by an ecological assessment included metal concentrations (arsenic, cadmium, copper, molybdenum, nickel, selenium, silver, and vanadium), benthic fauna community structure, and sediment toxicity. The collected sediments were composed of sandy-silt sized particles, with 2.4% to 9.1% organic carbon. Metal concentrations at sample stations were elevated relative to sediments collected from reference stations. For example, average cadmium concentrations ranged from 13 to 48 mg/kg at sample stations and 0.72 to 3.2 mg/kg atmore » reference stations; selenium concentrations ranged from 4.7 to 91 mg/kg at sample stations and 0.82 to 2.7 mg/kg at reference stations. Soda Creek has a relatively low flow gradient and the benthic fauna at both reference and sample stations was dominated by oligochaete worms and chironomid midge larvae. Taxonomic richness at individual sites ranged from 4.3 to 6.7 and 6 to 10.3 at reference and sample sites, respectively. There was no significant evidence of toxicity at any location sampled. Cluster analysis showed that the benthic community structure of many of the sample stations could not be distinguished from the reference stations. Canonical correlation analysis showed there was a significant relationship between benthic fauna and metal concentration, but there was not a consistent difference between sample and reference stations. For Soda Creek, local phenomena were more significant to benthic community structure than large-scale patterns of metal accumulation. Using the Triad approach, the authors concluded there has been no adverse effect of metal concentrations on the benthic community of Soda Creek.« less

The internal microstructure and fibrous mineralogy of fly ash from coal-burning power stations.

PubMed

Brown, Patrick; Jones, Tim; BéruBé, Kelly

2011-12-01

Coal fly ash (CFA) is a significant environmental pollutant that presents a respiratory hazard when airborne. Although previous studies have identified the mineral components of CFA, there is a paucity of information on the structural habits of these minerals. Samples from UK, Polish and Chinese power stations were studied to further our understanding of the factors that affect CFA geochemistry and mineralogy. ICP-MS, FE-SEM/EDX, XRD, and laser diffraction were used to study physicochemical characteristics. Analysis revealed important differences in the elemental compositions and particle size distributions of samples between sites. Microscopy of HF acid-etched CFA revealed the mullite present possesses a fibrous habit; fibres ranged in length between 1 and 10 μm. Respirable particles (<10 μm) were frequently observed to contain fibrous mullite. We propose that the biopersistence of these refractory fibres in the lung environment could be contributing towards chronic lung diseases seen in communities and individuals continually exposed to high levels of CFA. Copyright © 2011 Elsevier Ltd. All rights reserved.

Evaluation of fisher (Pekania pennanti) restoration in Olympic National Park and the Olympic Recovery Area: 2015 final annual progress report

USGS Publications Warehouse

Happe, Patricia J.; Jenkins, Kurt J.; Kay, Thomas J.; Pilgrim, Kristie; Schwartz, Michael K; Lewis, Jeffrey C.; Aubry, Keith B.

2016-01-01

With the translocation and release of 90 fishers (Pekania pennanti) from British Columbia to Olympic National Park during 2008–2010, the National Park Service (NPS) and Washington Department of Fish and Wildlife (WDFW) accomplished the first phase of fisher restoration in Washington State. Beginning in 2013, we initiated a new research project to determine the current status of fishers on Washington’s Olympic Peninsula 3–8 years after the releases and evaluate the short-term success of the restoration program. Objectives of the study are to determine the current distribution of fishers and proportion of the recovery area that is currently occupied by fishers, determine several genetic characteristics of the reintroduced population, and determine reproductive success of the founding animals through genetic studies. During 2015, we continued working with a broad coalition of cooperating agencies, tribes, and nongovernmental organizations (NGO) to collect data on fisher distribution and genetics using noninvasive sampling methods. The primary sampling frame consisted of 157 24-km2 hexagons (hexes) distributed across all major land ownerships within the Olympic Peninsula target survey area. In 2014 we expanded the study by adding 58 more hexes to an expanded study area in response to incidental fisher observations outside of the target area obtained in 2013; 49 hexes were added south and 9 to the east of the target area. During 2015, Federal, State, Tribal and NGO biologists and volunteers established three Distributioned motion-sensing camera stations, paired with hair snaring devices, in 87 hexes; 75 in the targeted area and 12 in the expansion areas. Each paired camera/hair station was left in place for approximately 6 weeks, with three checks on 2-week intervals. We documented fisher presence in 7 of the 87 hexagons. Four fishers were identified through microsatellite DNA analyses. The 4 identified fishers included 1 of the original founding population of 90 and 3 new recruits to the population. Three additional fishers were detected with cameras but not DNA, consequently their identities were unknown. All fisher detections were in the target area. Additionally, we identified 46 other species of wildlife at the baited camera stations. We also obtained 4 additional confirmed records of fishers in the study area through photographs provided by the public and incidental live capture. During 2016, we plan to resample 69 hexagons sampled in the target area in 2014 and 12 new hexes in the expansion area. In addition, we plan to sample non-selected hexes in-between hexes where we had a cluster of fishers in 2014, to provide better understanding of occupancy patterns and minimum number of individuals in an area where fishers appear to be concentrating.

Space Station power distribution and control

NASA Technical Reports Server (NTRS)

Willis, A. H.

1986-01-01

A general description of the Space Station is given with the basic requirements of the power distribution and controls system presented. The dual bus and branch circuit concepts are discussed and a computer control method presented.

Space Station Freedom power management and distribution system design

NASA Technical Reports Server (NTRS)

Teren, Fred

1989-01-01

The design is described of the Space Station Freedom Power Management and Distribution (PMAD) System. In addition, the significant trade studies which were conducted are described, which led to the current PMAD system configuration.

47 CFR 74.783 - Station identification.

Code of Federal Regulations, 2010 CFR

2010-10-01

..., AUXILIARY, SPECIAL BROADCAST AND OTHER PROGRAM DISTRIBUTIONAL SERVICES Low Power TV, TV Translator, and TV Booster Stations § 74.783 Station identification. (a) Each low power TV and TV translator station not..., whose signal is being rebroadcast, to identify the translator station by transmitting an easily readable...

Recording Fathometer Techniques for Determining Distribution and Biomass of Hydrilla verticillata Royle.

DTIC Science & Technology

1980-10-01

infestation or extent of open water was measured following the same procedures described for deter- fmination of transect percent cover. This value was...procedure where the last vegetation type ended along the transect (i.e. hydrilla, eelgrass, open water ), vegetation coverage was determined for the entire...ated open water , no measurements were made. Approximately 150 to 200 prediction stations were used per monthly sample. 61. For sparse and thick

Nonstationarity in timing of extreme precipitation across China and impact of tropical cyclones

NASA Astrophysics Data System (ADS)

Gu, Xihui; Zhang, Qiang; Singh, Vijay P.; Shi, Peijun

2017-02-01

This study examines the seasonality and nonstationarity in the timing of extreme precipitation obtained by annual maximum (AM) sampling and peak-over-threshold (POT) sampling techniques using circular statistics. Daily precipitation data from 728 stations with record length of at least 55 years across China were analyzed. In general, the average seasonality is subject mainly to summer season (June-July - August), which is potentially related to East Asian monsoon and Indian monsoon activities. The strength of precipitation seasonality varied across China with the highest strength being in northeast, north, and central-north China; whereas the weakest seasonality was found in southeast China. There are three seasonality types: circular uniform, reflective symmetric, and asymmetric. However, the circular uniform seasonality of extreme precipitation was not detected at stations across China. The asymmetric distribution was observed mainly in southeast China, and the reflective distribution of precipitation extremes was also identified the other regions besides the above-mentioned regions. Furthermore, a strong signal of nonstationarity in the seasonality was detected at half of the weather stations considered in the study, exhibiting a significant shift in the timing of extreme precipitation, and also significant trends in the average and strength of seasonality. Seasonal vapor flux and related delivery pathways and also tropical cyclones (TCs) are most probably the driving factors for the shifts or changes in the seasonality of extreme precipitation across China. Timing of precipitation extremes is closely related to seasonal shifts of floods and droughts and which means much for management of agricultural irrigation and water resources management. This study sheds new light on nonstationarity in timing of precipitation extremes which differs from existing ones which focused on precipitation extremes from perspective of magnitude and intensity.

Contaminated product water as the source of Phialemonium curvatum bloodstream infection among patients undergoing hemodialysis.

PubMed

Rao, Carol Y; Pachucki, Constance; Cali, Salvatore; Santhiraj, Mangai; Krankoski, Kathi L K; Noble-Wang, Judith A; Leehey, David; Popli, Subhash; Brandt, Mary E; Lindsley, Mark D; Fridkin, Scott K; Arduino, Matthew J

2009-09-01

We investigated a cluster of cases of bloodstream infection (BSI) due to the mold Phialemonium at a hemodialysis center in Illinois and conducted a cohort study to identify risk factors. Environmental assessment and cohort study. A hemodialysis center in a tertiary care hospital. A case patient was defined as a person who underwent dialysis at the center and had a blood sample that tested positive for Phialemonium curvatum on culture. We reviewed microbiology and medical records and tested water, surface, and dialysate samples by culture. Molds isolated from environmental and clinical specimens were identified by their morphological features and confirmed by sequencing DNA. We identified 2 case patients with BSI due to P. curvatum. Both became febrile and hypotensive while undergoing dialysis on the same machine at the same treatment station, although on different days. Dialysis machines were equipped with waste handling option ports that are used to discard dialyzer priming fluid. We isolated P. curvatum from the product water (ie, water used for dialysis purposes) at 2 of 19 treatment stations, one of which was the implicated station. The source of P. curvatum was likely the water distribution system. To our knowledge, this is the first report of patients acquiring a mold BSI from contaminated product water. The route of exposure in these cases of BSI due to P. curvatum may be related to the malfunction and improper maintenance of the waste handling option ports. Waste handling option ports have been previously implicated as the source of bacterial BSI due to the backflow of waste fluid into a patient's blood line. No additional cases of infection were noted after remediation of the water distribution system and after discontinuing use of waste handling option ports at the facility.

Joint distribution of temperature and precipitation in the Mediterranean, using the Copula method

NASA Astrophysics Data System (ADS)

Lazoglou, Georgia; Anagnostopoulou, Christina

2018-03-01

This study analyses the temperature and precipitation dependence among stations in the Mediterranean. The first station group is located in the eastern Mediterranean (EM) and includes two stations, Athens and Thessaloniki, while the western (WM) one includes Malaga and Barcelona. The data was organized in two time periods, the hot-dry period and the cold-wet one, composed of 5 months, respectively. The analysis is based on a new statistical technique in climatology: the Copula method. Firstly, the calculation of the Kendall tau correlation index showed that temperatures among stations are dependant during both time periods whereas precipitation presents dependency only between the stations located in EM or WM and only during the cold-wet period. Accordingly, the marginal distributions were calculated for each studied station, as they are further used by the copula method. Finally, several copula families, both Archimedean and Elliptical, were tested in order to choose the most appropriate one to model the relation of the studied data sets. Consequently, this study achieves to model the dependence of the main climate parameters (temperature and precipitation) with the Copula method. The Frank copula was identified as the best family to describe the joint distribution of temperature, for the majority of station groups. For precipitation, the best copula families are BB1 and Survival Gumbel. Using the probability distribution diagrams, the probability of a combination of temperature and precipitation values between stations is estimated.

Occurrence and seasonal distribution of polycyclic aromatic hydrocarbons and legacy and current-use pesticides in air from a Mediterranean coastal lagoon (Mar Menor, SE Spain).

PubMed

Carratalá, A; Moreno-González, R; León, V M

2017-01-01

The occurrence and seasonal distribution of polycyclic aromatic hydrocarbons (PAHs) and legacy and current-use pesticides (CUPs) in air were characterized around the Mar Menor lagoon using both active and passive sampling devices. The seasonal distribution of these pollutants was determined at 6 points using passive samplers. Passive sampler sampling rates were estimated for all detected analytes using an active sampler, considering preferentially winter data, due to probable losses in active sampling during summer (high temperatures and solar irradiation). The presence of 28 compounds (14 CUPs, 11 PAHs and 3 organochlorinated pesticides) were detected in air by polyurethane passive sampling. The most commonly detected contaminants (>95% of samples) in air were chlorpyrifos, chlorpyrifos-methyl and phenanthrene. The maximum concentrations corresponded to phenanthrene (6000 pg m -3 ) and chlorpyrifos (4900 pg m -3 ). The distribution of contaminants was spatially and seasonally heterogeneous. The highest concentrations of PAHs were found close to the airport, while the highest concentrations of pesticides were found in the influence area of agricultural fields (western stations). PAH and herbicide concentrations were higher in winter than in the other seasons, although some insecticides such as chlorpyrifos were more abundant in autumn. The presence of PAHs and legacy and current-use pesticides in air confirmed their transference potential to marine coastal areas such as the Mar Menor lagoon. Copyright © 2016 Elsevier Ltd. All rights reserved.

Constraining Particle Variation in Lunar Regolith for Simulant Design

NASA Technical Reports Server (NTRS)

Schrader, Christian M.; Rickman, Doug; Stoeser, Douglas; Hoelzer, Hans

2008-01-01

Simulants are used by the lunar engineering community to develop and test technologies for In Situ Resource Utilization (ISRU), excavation and drilling, and for mitigation of hazards to machinery and human health. Working with the United States Geological Survey (USGS), other NASA centers, private industry and academia, Marshall Space Flight Center (MSFC) is leading NASA s lunar regolith simulant program. There are two main efforts: simulant production and simulant evaluation. This work requires a highly detailed understanding of regolith particle type, size, and shape distribution, and of bulk density. The project has developed Figure of Merit (FoM) algorithms to quantitatively compare these characteristics between two materials. The FoM can be used to compare two lunar regolith samples, regolith to simulant, or two parcels of simulant. In work presented here, we use the FoM algorithm to examine the variance of particle type in Apollo 16 highlands regolith core and surface samples. For this analysis we have used internally consistent particle type data for the 90-150 m fraction of Apollo core 64001/64002 from station 4, core 60009/60010 from station 10, and surface samples from various Apollo 16 stations. We calculate mean modal compositions for each core and for the group of surface samples and quantitatively compare samples of each group to its mean as a measurement of within-group variance; we also calculate an FoM for every sample against the mean composition of 64001/64002. This gives variation with depth at two locations and between Apollo 16 stations. Of the tested groups, core 60009/60010 has the highest internal variance with an average FoM score of 0.76 and core 64001/64002 has the lowest with an average FoM of 0.92. The surface samples have a low but intermediate internal variance with an average FoM of 0.79. FoM s calculated against the 64001/64002 mean reference composition range from 0.79-0.97 for 64001/64002, from 0.41-0.91 for 60009/60010, and from 0.54-0.93 for the surface samples. Six samples fall below 0.70, and they are also the least mature (i.e., have the lowest I(sub s)/FeO). Because agglutinates are the dominant particle type and the agglutinate population increases with sample maturity (I(sub s)/FeO), the maturity of the sample relative to the reference is a prime determinant of the particle type FoM score within these highland samples.

Dynamics of harmful dinoflagellates driven by temperature and salinity in a northeastern Mediterranean lagoon.

PubMed

Dhib, Amel; Frossard, Victor; Turki, Souad; Aleya, Lotfi

2013-04-01

To attempt to determine the effects of temperature and salinity on the dynamics of the dinoflagellate community, a monthly sampling was carried out from October 2008 to March 2009 at eight sampling stations in Ghar El Melh Lagoon (GML; Mediterranean Sea, Northern Tunisia). Dinoflagellates were dominant among plankton, accounting for 73.9 % of the lagoon's overall plankton community, and were comprised of 25 different species among which 17 were reported in the literature as harmful. While no significant difference was found in the distribution of dinoflagellates among the stations, a strong monthly difference was observed. This temporal variability was due to an increase in the abundance of Prorocentrum micans from December to February, leading to a strong decrease in the Shannon diversity index from station to station. At the onset of P. micans development, dinoflagellate abundances reached 1.26.10(5) cells l(-1). A redundance analysis indicates that both temperature and salinity have a significant effect on the dynamics of the dinoflagellate community. Using a generalized additive model, both temperature and salinity appear to have significant nonlinear relationships with P. micans abundances. Model predictions indicate that outbreaks of P. micans may occur at a temperature below 22.5 °C and with salinity above 32.5. We discuss our results against a backdrop of climate change which, by affecting temperature and salinity, is likely to have an antagonistic impact on P. micans development and subsequently on the dinoflagellate dynamics in GML.

Elevational species shifts in a warmer climate are overestimated when based on weather station data.

PubMed

Scherrer, Daniel; Schmid, Samuel; Körner, Christian

2011-07-01

Strong topographic variation interacting with low stature alpine vegetation creates a multitude of micro-habitats poorly represented by common 2 m above the ground meteorological measurements (weather station data). However, the extent to which the actual habitat temperatures in alpine landscapes deviate from meteorological data at different spatial scales has rarely been quantified. In this study, we assessed thermal surface and soil conditions across topographically rich alpine landscapes by thermal imagery and miniature data loggers from regional (2-km(2)) to plot (1-m(2)) scale. The data were used to quantify the effects of spatial sampling resolution on current micro-habitat distributions and habitat loss due to climate warming scenarios. Soil temperatures showed substantial variation among slopes (2-3 K) dependent on slope exposure, within slopes (3-4 K) due to micro-topography and within 1-m(2) plots (1 K) as a result of plant cover effects. A reduction of spatial sampling resolution from 1 × 1 m to 100 × 100 m leads to an underestimation of current habitat diversity by 25% and predicts a six-times higher habitat loss in a 2-K warming scenario. Our results demonstrate that weather station data are unable to reflect the complex thermal patterns of aerodynamically decoupled alpine vegetation at the investigated scales. Thus, the use of interpolated weather station data to describe alpine life conditions without considering the micro-topographically induced thermal mosaic might lead to misinterpretation and inaccurate prediction.

47 CFR 25.103 - Definitions.

Code of Federal Regulations, 2012 CFR

2012-10-01

...) Communication-satellite earth station complex. The term communication-satellite earth station complex includes transmitters, receivers, and communications antennas at the earth station site together with the... communication to terrestrial distribution system(s). (e) Communication-satellite earth station complex functions...

47 CFR 25.103 - Definitions.

Code of Federal Regulations, 2011 CFR

2011-10-01

...) Communication-satellite earth station complex. The term communication-satellite earth station complex includes transmitters, receivers, and communications antennas at the earth station site together with the... communication to terrestrial distribution system(s). (e) Communication-satellite earth station complex functions...

Distribution and sources of surfzone bacteria at Huntington Beach before and after disinfection on an ocean outfall - A frequency-domain analysis

USGS Publications Warehouse

Noble, M.A.; Xu, J. P.; Robertson, G.L.; Rosenfeld, L.K.

2006-01-01

Fecal indicator bacteria (FIB) were measured approximately 5 days a week in ankle-depth water at 19 surfzone stations along Huntington Beach and Newport Beach, California, from 1998 to the end of 2003. These sampling periods span the time before and after treated sewage effluent, discharged into the coastal ocean from the local outfall, was disinfected. Bacterial samples were also taken in the vicinity of the outfall during the pre- and post-disinfection periods. Our analysis of the results from both data sets suggest that land-based sources, rather than the local outfall, were the source of the FIB responsible for the frequent closures and postings of local beaches in the summers of 2001 and 2002. Because the annual cycle is the dominant frequency in the fecal and total coliform data sets at most sampling stations, we infer that sources associated with local runoff were responsible for the majority of coliform contamination along wide stretches of the beach. The dominant fortnightly cycle in enterococci at many surfzone sampling stations suggests that the source for these relatively frequent bacteria contamination events in summer is related to the wetting and draining of the land due to the large tidal excursions found during spring tides. Along the most frequently closed section of the beach at stations 3N-15N, the fortnightly cycle is dominant in all FIBs. The strikingly different spatial and spectral patterns found in coliform and in enterococci suggest the presence of different sources, at least for large sections of beach. The presence of a relatively large enterococci fortnightly cycle along the beaches near Newport Harbor indicates that contamination sources similar to those found off Huntington Beach are present, though not at high enough levels to close the Newport beaches. ?? 2006 Elsevier Ltd. All rights reserved.

A framework for building real-time expert systems

NASA Technical Reports Server (NTRS)

Lee, S. Daniel

1991-01-01

The Space Station Freedom is an example of complex systems that require both traditional and artificial intelligence (AI) real-time methodologies. It was mandated that Ada should be used for all new software development projects. The station also requires distributed processing. Catastrophic failures on the station can cause the transmission system to malfunction for a long period of time, during which ground-based expert systems cannot provide any assistance to the crisis situation on the station. This is even more critical for other NASA projects that would have longer transmission delays (e.g., the lunar base, Mars missions, etc.). To address these issues, a distributed agent architecture (DAA) is proposed that can support a variety of paradigms based on both traditional real-time computing and AI. The proposed testbed for DAA is an autonomous power expert (APEX) which is a real-time monitoring and diagnosis expert system for the electrical power distribution system of the space station.

Polycyclic aromatic hydrocarbons in soil and surface marine sediment near Jubany Station (Antarctica). Role of permafrost as a low-permeability barrier.

PubMed

Curtosi, Antonio; Pelletier, Emilien; Vodopivez, Cristian L; Mac Cormack, Walter P

2007-09-20

Although Antarctica is still considered as one of the most pristine areas of the world, the growing tourist and fisheries activities as well as scientific operations and their related logistic support are responsible for an increasing level of pollutants in this fragile environment. Soils and coastal sediments are significantly affected near scientific stations particularly by polycyclic aromatic hydrocarbons (PAHs). In this work sediment and soil were sampled in two consecutive summer Antarctic expeditions at Potter Cove and peninsula, in the vicinity of Jubany Station (South Shetland Islands). Two- and 3-ring PAHs (methylnaphthalene, fluorene, phenanthrene and anthracene) were the main compounds found in most sites, although total PAH concentrations showed relatively low levels compared with other human-impacted areas in Antarctica. Pattern distribution of PAHs observed in samples suggested that low-temperature combustion processes such as diesel motor combustion and open-field garbage burning are the main sources of these compounds. An increase in PAH concentrations was observed from surface to depth into the active soil layer except for a unique sampling site where a fuel spill had been recently reported and where an inverted PAH concentration gradient was observed. The highest level was detected in the upper layer of permafrost followed by a sharp decrease in depth, showing this layer is acting as a barrier for downward PAH migration. When PAH levels in soil from both sampling programs were compared a significant decrease (p<0.01) was observed in summer 2005 (range at 75-cm depth: 12+/-1-153+/-22 ng/g) compared to summer 2004 (range at 75-cm depth: 162+/-15-1182+/-113 ng/g) whereas concentrations in surface sediment collected nearby the station PAHs increased drastically in 2005 (range: 36+/-3-1908+/-114 ng/g) compared to 2004 (range: 28+/-3-312+/-24 ng/g). Precipitation regime and water run off suggest that an important wash out of soil-PAHs occurred during the interval time between samplings. Results showed that the present PAH contamination level of Jubany Station is relatively low compared to other reported cases in Antarctica but also suggests that an increase in rain and in thawing processes caused by the global warming could result in an important soil-associated PAH mobilization with unpredictable consequences for the biota of Potter Cove.

Simultaneous beam sampling and aperture shape optimization for SPORT.

PubMed

Zarepisheh, Masoud; Li, Ruijiang; Ye, Yinyu; Xing, Lei

2015-02-01

Station parameter optimized radiation therapy (SPORT) was recently proposed to fully utilize the technical capability of emerging digital linear accelerators, in which the station parameters of a delivery system, such as aperture shape and weight, couch position/angle, gantry/collimator angle, can be optimized simultaneously. SPORT promises to deliver remarkable radiation dose distributions in an efficient manner, yet there exists no optimization algorithm for its implementation. The purpose of this work is to develop an algorithm to simultaneously optimize the beam sampling and aperture shapes. The authors build a mathematical model with the fundamental station point parameters as the decision variables. To solve the resulting large-scale optimization problem, the authors devise an effective algorithm by integrating three advanced optimization techniques: column generation, subgradient method, and pattern search. Column generation adds the most beneficial stations sequentially until the plan quality improvement saturates and provides a good starting point for the subsequent optimization. It also adds the new stations during the algorithm if beneficial. For each update resulted from column generation, the subgradient method improves the selected stations locally by reshaping the apertures and updating the beam angles toward a descent subgradient direction. The algorithm continues to improve the selected stations locally and globally by a pattern search algorithm to explore the part of search space not reachable by the subgradient method. By combining these three techniques together, all plausible combinations of station parameters are searched efficiently to yield the optimal solution. A SPORT optimization framework with seamlessly integration of three complementary algorithms, column generation, subgradient method, and pattern search, was established. The proposed technique was applied to two previously treated clinical cases: a head and neck and a prostate case. It significantly improved the target conformality and at the same time critical structure sparing compared with conventional intensity modulated radiation therapy (IMRT). In the head and neck case, for example, the average PTV coverage D99% for two PTVs, cord and brainstem max doses, and right parotid gland mean dose were improved, respectively, by about 7%, 37%, 12%, and 16%. The proposed method automatically determines the number of the stations required to generate a satisfactory plan and optimizes simultaneously the involved station parameters, leading to improved quality of the resultant treatment plans as compared with the conventional IMRT plans.

Simultaneous beam sampling and aperture shape optimization for SPORT

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zarepisheh, Masoud; Li, Ruijiang; Xing, Lei, E-mail: Lei@stanford.edu

Purpose: Station parameter optimized radiation therapy (SPORT) was recently proposed to fully utilize the technical capability of emerging digital linear accelerators, in which the station parameters of a delivery system, such as aperture shape and weight, couch position/angle, gantry/collimator angle, can be optimized simultaneously. SPORT promises to deliver remarkable radiation dose distributions in an efficient manner, yet there exists no optimization algorithm for its implementation. The purpose of this work is to develop an algorithm to simultaneously optimize the beam sampling and aperture shapes. Methods: The authors build a mathematical model with the fundamental station point parameters as the decisionmore » variables. To solve the resulting large-scale optimization problem, the authors devise an effective algorithm by integrating three advanced optimization techniques: column generation, subgradient method, and pattern search. Column generation adds the most beneficial stations sequentially until the plan quality improvement saturates and provides a good starting point for the subsequent optimization. It also adds the new stations during the algorithm if beneficial. For each update resulted from column generation, the subgradient method improves the selected stations locally by reshaping the apertures and updating the beam angles toward a descent subgradient direction. The algorithm continues to improve the selected stations locally and globally by a pattern search algorithm to explore the part of search space not reachable by the subgradient method. By combining these three techniques together, all plausible combinations of station parameters are searched efficiently to yield the optimal solution. Results: A SPORT optimization framework with seamlessly integration of three complementary algorithms, column generation, subgradient method, and pattern search, was established. The proposed technique was applied to two previously treated clinical cases: a head and neck and a prostate case. It significantly improved the target conformality and at the same time critical structure sparing compared with conventional intensity modulated radiation therapy (IMRT). In the head and neck case, for example, the average PTV coverage D99% for two PTVs, cord and brainstem max doses, and right parotid gland mean dose were improved, respectively, by about 7%, 37%, 12%, and 16%. Conclusions: The proposed method automatically determines the number of the stations required to generate a satisfactory plan and optimizes simultaneously the involved station parameters, leading to improved quality of the resultant treatment plans as compared with the conventional IMRT plans.« less

Nutrient concentrations, loads, and yields in the Eucha-Spavinaw Basin, Arkansas and Oklahoma, 2002-09

USGS Publications Warehouse

Esralew, Rachel A.; Tortorelli, Robert L.

2010-01-01

The city of Tulsa, Oklahoma, uses Lake Eucha and Spavinaw Lake in the Eucha-Spavinaw Basin in northwestern Arkansas and northeastern Oklahoma for public water supply. The city has spent millions of dollars over the last decade to eliminate taste and odor problems in the drinking water from the Eucha-Spavinaw system, which may be attributable to blue-green algae. Increases in the algal biomass in the lakes may be attributable to increases in nutrient concentrations in the lakes and in the waters feeding the lakes. The U.S. Geological Survey, in cooperation with the City of Tulsa, investigated and summarized total nitrogen and total phosphorus concentrations in water samples and provided estimates of nitrogen and phosphorus loads, yields, and flow-weighted concentrations during base flow and runoff for two streams discharging to Lake Eucha for the period January 2002 through December 2009. This report updates a previous report that used data from water-quality samples collected from January 2002 through December 2006. Based on the results from the Mann-Whitney statistical test, unfiltered total nitrogen concentrations were significantly greater in runoff water samples than in base-flow water samples collected from Spavinaw Creek near Maysville and near Cherokee City, Arkansas; Spavinaw Creek near Colcord, Oklahoma, and Beaty Creek near Jay, Oklahoma. Nitrogen concentrations in runoff water samples collected from all stations generally increased with increasing streamflow. Nitrogen concentrations in base-flow and runoff water samples collected in Spavinaw Creek significantly increased from the station furthest upstream (near Maysville) to the Sycamore station and then significantly decreased from the Sycamore station to the station furthest downstream (near Colcord). Nitrogen concentrations in base-flow and runoff water samples collected from Beaty Creek were significantly less than base-flow and runoff water samples collected from Spavinaw Creek. Based on the results from the Mann-Whitney statistical test, unfiltered total phosphorus concentrations were significantly greater in runoff water samples than in base-flow water samples for the entire period for most stations, except in water samples collected from Spavinaw Creek near Cherokee City, in which no significant difference was detected for the entire period nor for any season. Phosphorus concentrations in runoff water samples collected from all stations generally increased with increasing streamflow. Based on results from a multi-stage Kruskal-Wallis statistical test, phosphorus concentrations in base-flow water samples collected from Spavinaw Creek significantly increased from the Maysville station to the Cherokee City station, probably because of discharge from a municipal wastewater-treatment plant between those stations. Phosphorus concentrations significantly decreased downstream from the Cherokee City station to the Colcord station. Phosphorus concentrations in base-flow water samples collected from Beaty Creek were significantly less than phosphorus in base-flow water samples collected from Spavinaw Creek downstream from the Maysville station. View report for unabridged abstract.

Research on the optimization of air quality monitoring station layout based on spatial grid statistical analysis method.

PubMed

Li, Tianxin; Zhou, Xing Chen; Ikhumhen, Harrison Odion; Difei, An

2018-05-01

In recent years, with the significant increase in urban development, it has become necessary to optimize the current air monitoring stations to reflect the quality of air in the environment. Highlighting the spatial representation of some air monitoring stations using Beijing's regional air monitoring station data from 2012 to 2014, the monthly mean particulate matter concentration (PM10) in the region was calculated and through the IDW interpolation method and spatial grid statistical method using GIS, the spatial distribution of PM10 concentration in the whole region was deduced. The spatial distribution variation of districts in Beijing using the gridding model was performed, and through the 3-year spatial analysis, PM10 concentration data including the variation and spatial overlay (1.5 km × 1.5 km cell resolution grid), the spatial distribution result obtained showed that the total PM10 concentration frequency variation exceeded the standard. It is very important to optimize the layout of the existing air monitoring stations by combining the concentration distribution of air pollutants with the spatial region using GIS.

Leveraging EarthScope USArray with the Central and Eastern United States Seismic Network

NASA Astrophysics Data System (ADS)

Busby, R.; Sumy, D. F.; Woodward, R.; Frassetto, A.; Brudzinski, M.

2015-12-01

Recent earthquakes, such as the 2011 M5.8 Mineral, Virginia earthquake, raised awareness of the comparative lack of knowledge about seismicity, site response to ground shaking, and the basic geologic underpinnings in this densely populated region. With this in mind, the National Science Foundation, United States Geological Survey, United States Nuclear Regulatory Commission, and Department of Energy supported the creation of the Central and Eastern United States Seismic Network (CEUSN). These agencies, along with the IRIS Consortium who operates the network, recognized the unique opportunity to retain EarthScope Transportable Array (TA) seismic stations in this region beyond the standard deployment duration of two years per site. The CEUSN project supports 159 broadband TA stations, more than 30 with strong motion sensors added, that are scheduled to operate through 2017. Stations were prioritized in regions of elevated seismic hazard that have not been traditionally heavily monitored, such as the Charlevoix and Central Virginia Seismic Zones, and in regions proximal to nuclear power plants and other critical facilities. The stations (network code N4) transmit data in real time, with broadband and strong motion sensors sampling at 100 samples per second. More broadly the CEUSN concept also recognizes the existing backbone coverage of permanently operating seismometers in the CEUS, and forms a network of over 300 broadband stations. This multi-agency collaboration is motivated by the opportunity to use one facility to address multiple missions and needs in a way that is rarely possible, and to produce data that enables both researchers and federal agencies to better understand seismic hazard potential and associated seismic risks. In June 2015, the CEUSN Working Group (www.usarray.org/ceusn_working_group) was formed to review and provide advice to IRIS Management on the performance of the CEUSN as it relates to the target scientific goals and objectives. Map shows the 159 CEUSN stations (yellow) that will be operated and maintained by the IRIS Consortium through 2017. The CEUSN stations were selected for proximity to nuclear power plants (black squares) and other critical infrastructure as well as to more evenly distribute seismic stations across the central and eastern United States.

Bayesian Processor of Output for Probabilistic Quantitative Precipitation Forecasting

NASA Astrophysics Data System (ADS)

Krzysztofowicz, R.; Maranzano, C. J.

2006-05-01

The Bayesian Processor of Output (BPO) is a new, theoretically-based technique for probabilistic forecasting of weather variates. It processes output from a numerical weather prediction (NWP) model and optimally fuses it with climatic data in order to quantify uncertainty about a predictand. The BPO is being tested by producing Probabilistic Quantitative Precipitation Forecasts (PQPFs) for a set of climatically diverse stations in the contiguous U.S. For each station, the PQPFs are produced for the same 6-h, 12-h, and 24-h periods up to 84- h ahead for which operational forecasts are produced by the AVN-MOS (Model Output Statistics technique applied to output fields from the Global Spectral Model run under the code name AVN). The inputs into the BPO are estimated as follows. The prior distribution is estimated from a (relatively long) climatic sample of the predictand; this sample is retrieved from the archives of the National Climatic Data Center. The family of the likelihood functions is estimated from a (relatively short) joint sample of the predictor vector and the predictand; this sample is retrieved from the same archive that the Meteorological Development Laboratory of the National Weather Service utilized to develop the AVN-MOS system. This talk gives a tutorial introduction to the principles and procedures behind the BPO, and highlights some results from the testing: a numerical example of the estimation of the BPO, and a comparative verification of the BPO forecasts and the MOS forecasts. It concludes with a list of demonstrated attributes of the BPO (vis- à-vis the MOS): more parsimonious definitions of predictors, more efficient extraction of predictive information, better representation of the distribution function of predictand, and equal or better performance (in terms of calibration and informativeness).

KSC-99pp1376

NASA Image and Video Library

1999-12-02

KENNEDY SPACE CENTER, FLA. -- STS-102 crew member Susan J. Helms looks over a Pressurized Mating Adapter (PMA-3) in the Space Station Processing Facility. The PMA-3 is a component of the International Space Station (ISS). Helms is one of three who will be staying on the ISS as the Expedition II crew. The others are Yuriy Vladimirovich Usachev and James S. Voss. Along with the crew, Mission STS-102 also will be carrying the Leonardo Multi-Purpose Logistics Module (MPLM) to the ISS. The Leonardo will be filled with equipment and supplies to outfit the U.S. laboratory module, which will have been carried to the ISS on a preceding Shuttle flight. In order to function as an attached station module as well as a cargo transport, logistics modules (there are three) also include components that provide some life support, fire detection and suppression, electrical distribution and computer functions. Eventually, the modules also will carry refrigerator freezers for transporting experiment samples and food to and from the station. On the return of STS-102 to Earth, it will bring back the first crew on the station: Bill Shepherd, Sergei Krikalev and Yuri Gidzenko. STS-102 is scheduled to launch no earlier than Oct. 19, 2000, from Launch Pad 39A, Kennedy Space Center

KSC-99pp1375

NASA Image and Video Library

1999-12-02

KENNEDY SPACE CENTER, FLA. -- Looking over a Pressurized Mating Adapter (PMA-3) in the Space Station Processing Facility are Arne Aamodt, with Johnson Space Center, Yuriy Vladimirovich Usachev and Susan J. Helms. Usachev and Helms are two members of the STS-102 crew, who will be staying on the International Space Station (ISS). The third crew member is James S. Voss. They have been designated the Expedition II crew. Mission STS-102 also will be carrying the Leonardo Multi-Purpose Logistics Module (MPLM) to the ISS. The Leonardo will be filled with equipment and supplies to outfit the U.S. laboratory module, which will have been carried to the ISS on a preceding Shuttle flight. In order to function as an attached station module as well as a cargo transport, logistics modules (there are three) also include components that provide some life support, fire detection and suppression, electrical distribution and computer functions. Eventually, the modules also will carry refrigerator freezers for transporting experiment samples and food to and from the station. On the return of STS-102 to Earth, it will bring back the first crew on the station: Bill Shepherd, Sergei Krikalev and Yuri Gidzenko. STS-102 is scheduled to launch no earlier than Oct. 19, 2000, from Launch Pad 39A, Kennedy Space Center

KSC-99pp1378

NASA Image and Video Library

1999-12-02

KENNEDY SPACE CENTER, FLA. -- From a work stand in the Space Station Processing Facility, STS-102 crew members James S. Voss (left) and Yuriy Vladimirovich Usachev (right), of Russia, look over the Pressurized Mating Adapter (PMA-3). The PMA-3 is a component of the International Space Station (ISS). Voss and Usachev are two crew members who will be staying on the ISS as the Expedition II crew. The third is Susan J. Helms. Along with the crew, Mission STS-102 also will be carrying the Leonardo Multi-Purpose Logistics Module (MPLM) to the ISS. The Leonardo will be filled with equipment and supplies to outfit the U.S. laboratory module, which will have been carried to the ISS on a preceding Shuttle flight. In order to function as an attached station module as well as a cargo transport, logistics modules (there are three) also include components that provide some life support, fire detection and suppression, electrical distribution and computer functions. Eventually, the modules also will carry refrigerator freezers for transporting experiment samples and food to and from the station. On the return of STS-102 to Earth, it will bring back the first crew on the station: Bill Shepherd, Sergei Krikalev and Yuri Gidzenko. STS-102 is scheduled to launch no earlier than Oct. 19, 2000, from Launch Pad 39A, Kennedy Space Center

KSC-99pp1377

NASA Image and Video Library

1999-12-02

KENNEDY SPACE CENTER, FLA. -- Members of the STS-102 crew, known as the Expedition II crew, and workers from Johnson Space Center get a close look at the Pressurized Mating Adapter (PMA-3) in the Space Station Processing Facility. The PMA-3 is a component of the International Space Station (ISS). Making up the Expedition II crew are James S. Voss, Susan J. Helms and Yuriy Vladimirovich Usachev, of Russia. Along with the crew, Mission STS-102 also will be carrying the Leonardo Multi-Purpose Logistics Module (MPLM) to the ISS. The Leonardo will be filled with equipment and supplies to outfit the U.S. laboratory module, which will have been carried to the ISS on a preceding Shuttle flight. In order to function as an attached station module as well as a cargo transport, logistics modules (there are three) also include components that provide some life support, fire detection and suppression, electrical distribution and computer functions. Eventually, the modules also will carry refrigerator freezers for transporting experiment samples and food to and from the station. On the return of STS-102 to Earth, it will bring back the first crew on the station: Bill Shepherd, Sergei Krikalev and Yuri Gidzenko. STS-102 is scheduled to launch no earlier than Oct. 19, 2000, from Launch Pad 39A, Kennedy Space Center

Single-station 6C beamforming

NASA Astrophysics Data System (ADS)

Nakata, N.; Hadziioannou, C.; Igel, H.

2017-12-01

Six-component measurements of seismic ground motion provide a unique opportunity to identify and decompose seismic wavefields into different wave types and incoming azimuths, as well as estimate structural information (e.g., phase velocity). By using the relationship between the transverse component and vertical rotational motion for Love waves, we can find the incident azimuth of the wave and the phase velocity. Therefore, when we scan the entire range of azimuth and slownesses, we can process the seismic waves in a similar way to conventional beamforming processing, without using a station array. To further improve the beam resolution, we use the distribution of amplitude ratio between translational and rotational motions at each time sample. With this beamforming, we decompose multiple incoming waves by azimuth and phase velocity using only one station. We demonstrate this technique using the data observed at Wettzell (vertical rotational motion and 3C translational motions). The beamforming results are encouraging to extract phase velocity at the location of the station, apply to oceanic microseism, and to identify complicated SH wave arrivals. We also discuss single-station beamforming using other components (vertical translational and horizontal rotational components). For future work, we need to understand the resolution limit of this technique, suitable length of time windows, and sensitivity to weak motion.

Nutrient Concentrations, Loads, and Yields in the Eucha-Spavinaw Basin, Arkansas and Oklahoma, 2002-2006

USGS Publications Warehouse

Tortorelli, Robert L.

2008-01-01

The City of Tulsa, Oklahoma, uses Lake Eucha and Spavinaw Lake in the Eucha-Spavinaw basin in northwestern Arkansas and northeastern Oklahoma for public water supply. Taste and odor problems in the water attributable to blue-green algae have increased in frequency. Changes in the algae community in the lakes may be attributable to increases in nutrient levels in the lakes, and in the waters feeding the lakes. The U.S. Geological Survey, in cooperation with the City of Tulsa, investigated and summarized nitrogen and phosphorus concentrations and provided estimates of nitrogen and phosphorus loads, yields, and flow-weighted concentrations in the Eucha-Spavinaw basin for three 3-year periods - 2002-2004, 2003-2005, and 2004-2006, to update a previous report that used data from water-quality samples for a 3-year period from January 2002 through December 2004. This report provides information needed to advance knowledge of the regional hydrologic system and understanding of hydrologic processes, and provides hydrologic data and results useful to multiple agencies for interstate agreements. Nitrogen and phosphorus concentrations were significantly greater in runoff samples than in base-flow samples for all three periods at Spavinaw Creek near Maysville, Arkansas; Spavinaw Creek near Colcord, Oklahoma, and Beaty Creek near Jay, Oklahoma. Runoff concentrations were not significantly greater than base-flow concentrations at Spavinaw Creek near Cherokee, Arkansas; and Spavinaw Creek near Sycamore, Oklahoma except for phosphorus during 2003-2005. Nitrogen concentrations in base-flow samples significantly increased downstream in Spavinaw Creek from the Maysville to Sycamore stations then significantly decreased from the Sycamore to the Colcord stations for all three periods. Nitrogen in base-flow samples from Beaty Creek was significantly less than in samples from Spavinaw Creek. Phosphorus concentrations in base-flow samples significantly increased from the Maysville to Cherokee stations in Spavinaw Creek for all three periods, probably because of a wastewater-treatment plant point source between those stations, and then significantly decreased downstream from the Cherokee to Colcord stations. Phosphorus in base-flow samples from Beaty Creek was significantly less than phosphorus in base-flow samples from Spavinaw Creek downstream from the Maysville station. Nitrogen concentrations in runoff samples were not significantly different among the stations on Spavinaw Creek for most of the three periods, except during 2003-2005 when runoff samples at the Colcord station were less than at the Sycamore station; however, the concentrations at Beaty Creek were significantly less than at all other stations. Phosphorus concentrations in runoff samples were not significantly different among the three downstream stations on Spavinaw Creek and were significantly different at the Maysville station on Spavinaw Creek and the Beaty Creek station, only during 2004-2006. Phosphorus and nitrogen concentrations in runoff samples from all stations generally increased with increasing streamflow. Estimated mean annual nitrogen total loads for the three 3-year periods were substantially greater at the Spavinaw Creek stations than at Beaty Creek and increased downstream from Maysville to Colcord in Spavinaw Creek, with the load at the Colcord station about 2 times that at Maysville station. Estimated mean annual nitrogen base-flow loads at the Spavinaw Creek stations were about 5 to 11 times greater than base-flow loads at Beaty Creek. The runoff component of the annual nitrogen total load for Beaty Creek was 85 to 89 percent; whereas, the range in the runoff component at the Spavinaw Creek stations was 60 to 71 percent. Estimated mean annual phosphorus total loads for the three 3-year periods were greater at the Spavinaw Creek stations from Cherokee to Colcord than at Beaty Creek and increased downstream from Maysville to Colcord in Spavinaw Creek, wit

Hypervelocity impact facility for simulating materials exposure to impact by space debris

NASA Technical Reports Server (NTRS)

Rose, M. F.; Best, S.; Chaloupka, T.; Stephens, B.; Crawford, G.

1993-01-01

As a result of man's venturing into space, the local debris contributed by his presence exceeds, at some orbital altitudes, that of the natural component. Man's contribution ranges from fuel residue to large derelect satellites that weigh many kilograms. Current debris models are able to predict the growth of the problem and suggest that spacecraft must employ armor or bumper shields for some orbital altitudes now, and that, the problem will become worse as a function of time. The practical upper limit to the velocity distribution is on the order of 40 km/s and is associated with the natural environment. The maximum velocity of the man-made component is in the 14-16 km/s range. The Long Duration Exposure Facility (LDEF) has verified that the 'high probability of impact' particles are in the microgram to milligram range. These particles can have significant effects on coatings, insulators, and thin metallic layers. The surface of thick materials becomes pitted and the local debris component is enhanced by ejecta from the debris spectrum in a controlled environment. The facility capability is discussed in terms of drive geometry, energetics, velocity distribution, diagnostics, and projectile/debris loading. The facility is currently being used to study impact phenomena on Space Station Freedom's solar array structure, other solar array materials, potential structural materials for use in the station, electrical breakdown in the space environment, and as a means of clarifying or duplicating the impact phenomena on the LDEF surfaces. The results of these experiments are described in terms of the mass/velocity distribution incident on selected samples, crater dynamics, and sample geometry.

47 CFR 74.1201 - Definitions.

Code of Federal Regulations, 2010 CFR

2010-10-01

..., AUXILIARY, SPECIAL BROADCAST AND OTHER PROGRAM DISTRIBUTIONAL SERVICES FM Broadcast Translator Stations and FM Broadcast Booster Stations § 74.1201 Definitions. (a) FM translator. A station in the broadcasting... another FM broadcast translator station without significantly altering any characteristics of the incoming...

47 CFR 74.1290 - FM translator and booster station information available on the Internet.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 47 Telecommunication 4 2012-10-01 2012-10-01 false FM translator and booster station information... DISTRIBUTIONAL SERVICES FM Broadcast Translator Stations and FM Broadcast Booster Stations § 74.1290 FM translator and booster station information available on the Internet. The Media Bureau's Audio Division...

47 CFR 74.1290 - FM translator and booster station information available on the Internet.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 47 Telecommunication 4 2014-10-01 2014-10-01 false FM translator and booster station information... DISTRIBUTIONAL SERVICES FM Broadcast Translator Stations and FM Broadcast Booster Stations § 74.1290 FM translator and booster station information available on the Internet. The Media Bureau's Audio Division...

47 CFR 74.1290 - FM translator and booster station information available on the Internet.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 47 Telecommunication 4 2013-10-01 2013-10-01 false FM translator and booster station information... DISTRIBUTIONAL SERVICES FM Broadcast Translator Stations and FM Broadcast Booster Stations § 74.1290 FM translator and booster station information available on the Internet. The Media Bureau's Audio Division...

Micro- and mesoplastics in Northeast Levantine coast of Turkey: The preliminary results from surface samples.

PubMed

Gündoğdu, Sedat; Çevik, Cem

2017-05-15

The determination of the microplastic distribution will be beneficial as a measure of the potential effects on the environment. The Mediterranean Sea had a high risk of pollution as it was enclosed by highly populated and industrialized countries. Here, we determined the level of micro- and mesoplastic pollution in Iskenderun and Mersin Bays, located in the Northeastern Levantine coast of Turkey. The average level of both micro- and mesoplastic was determined to be 0.376 item/m 2 at seven stations. The highest level was determined in Mersin Bay at the mouth of the Seyhan river (Station no. 7, with 906 items), and the lowest level was found in Station no. 4 in Iskenderun Bay (78 items). As a result of this study, it was determined that the microplastic pollution level in the Mediterranean coast of Turkey was similar to the other regions of the Mediterranean Sea. Copyright © 2017 Elsevier Ltd. All rights reserved.

Metal (Al, Fe, Mn and Cu) distributions and origins of polycyclic aromatic hydrocarbons (PAHs) in the surface sediments of the Marmara Sea and the coast of Istanbul, Turkey.

PubMed

Taşkın, Ö S; Aksu, A; Balkıs, N

2011-11-01

In this study, total metal (Al, Fe, Mn and Cu) and PAHs analyses have been done in the surface sediments. Sediment samples have been collected from seven parts of the Marmara Sea and the coast of Istanbul during 2009. Total Al, Fe, Mn and Cu contents vary between 1.8% and 5.4%; 1.1% and 2.8%; 122 and 259 μg g(-1); 27 and 416 μg g(-1), respectively. EF and CF values of Fe and Mn are lower than 1.5 and 1, respectively, in all the stations. Total PAH contents range between 135 and 6009 ng g(-1) in the surface sediments. The origin of PAHs has been found pyrolitic according to the Phe/Ant ratio in the all stations. Contrastingly, at K0, MKC and MY1 Stations, PAH origins have been observed petrogenic according to the Flu/Pyr ratio. Copyright © 2011 Elsevier Ltd. All rights reserved.

The use of epilithic Antarctic lichens (Usnea aurantiacoatra and U. antartica) to determine deposition patterns of heavy metals in the Shetland Islands, Antarctica.

PubMed

Poblet, A; Andrade, S; Scagliola, M; Vodopivez, C; Curtosi, A; Pucci, A; Marcovecchio, J

1997-11-27

Trace-metal contents were recorded for the epilithic antarctic lichens Usnea aurantiacoatra and U. antartica, sampled close to the Argentine scientific station 'Jubany' on '25 de Mayo' (King George) Island, in the Southern Shetland Archipelago (Antarctica). The corresponding heavy-metal levels have been measured through atomic absorption spectrophotometry, following internationally accepted analytical methods. The results obtained support the hypothesis that an atmospheric circulation of trace metals exists on the assessed area, and the activities developed at the different scientific stations located on this island would be a potential source of heavy metals to the evaluated environment. The geographical distribution of trace metals atmospherically transported in the area close to 'Jubany Station' was studied through the corresponding metal contents of the assessed lichens. Finally, the suitability of both analyzed lichen species, Usnea aurantiacoatra and U. antartica, as biological indicators for quantitative monitoring of airborne metals for this antarctic environment was recognized.

Rainfall, Streamflow, and Water-Quality Data During Stormwater Monitoring, Halawa Stream Drainage Basin, Oahu, Hawaii, July 1, 2004 to June 30, 2005

USGS Publications Warehouse

Young, Stacie T.M.; Ball, Marcael T.J.

2005-01-01

Storm runoff water-quality samples were collected as part of the State of Hawaii Department of Transportation Stormwater Monitoring Program. This program is designed to assess the effects of highway runoff and urban runoff on Halawa Stream. For this program, rainfall data were collected at two stations, continuous streamflow data at two stations, and water-quality data at five stations, which include the two continuous streamflow stations. This report summarizes rainfall, streamflow, and water-quality data collected between July 1, 2004 and June 30, 2005. A total of 15 samples was collected over three storms during July 1, 2004 to June 30, 2005. In general, an attempt was made to collect grab samples nearly simultaneously at all five stations and flow-weighted time-composite samples at the three stations equipped with automatic samplers. However, all three storms were partially sampled because either not all stations were sampled or not all composite samples were collected. Samples were analyzed for total suspended solids, total dissolved solids, nutrients, chemical oxygen demand, and selected trace metals (cadmium, chromium, copper, lead, nickel, and zinc). Chromium and nickel were added to the analysis starting October 1, 2004. Grab samples were additionally analyzed for oil and grease, total petroleum hydrocarbons, fecal coliform, and biological oxygen demand. Quality-assurance/quality-control samples were also collected during storms and during routine maintenance to verify analytical procedures and check the effectiveness of equipment-cleaning procedures.

Temporal and spatial distribution of particulate carcinogens and mutagens in Bangkok, Thailand.

PubMed

Pongpiachan, Siwatt; Choochuay, C; Hattayanone, M; Kositanont, C

2013-01-01

To investigate the level of genotoxicity over Bangkok atmosphere, PM10 samples were collected at the Klongchan Housing Authority (KHA), Nonsree High School (NHS), Watsing High School (WHS), Electricity Generating Authority of Thailand (EGAT), Chokchai 4 Police Station (CPS), Dindaeng Housing Authority (DHA) and Badindecha High School (BHS). For all monitoring stations, each sample covered a period of 24 hours taken at a normal weekday every month from January-December 2006 forming a database of 84 individual air samples (i.e. 12?7=84). Atmospheric concentrations of low molecular weight PAHs (i.e. phenanthrene, anthracene, pyrene and fluoranthene) were measured in PM10 at seven observatory sites operated by the pollution control department of Thailand (PCD). The mutagenicity of extracts of the samples was compared in Salmonella according to standard Ames test method. The dependence of the effects on sampling time and on sampling location was investigated with the aid of a calculation of mutagenic index (MI). This MI was used to estimate the increase in mutagenicity above background levels (i.e. negative control) at the seven monitoring sites in urban area of Bangkok due to anthropogenic emissions within that area. Applications of the AMES method showed that the average MI of PM10 collected at all sampling sites were 1.37±0.10 (TA98; +S9), 1.24±0.08 (TA98; -S9), 1.45±0.10 (TA100; +S9) and 1.30±0.09 (TA100; -S9) with relatively less variations. Analytical results reconfirm that the particulate PAH concentrations measured at PCD air quality monitoring stations are moderately low in comparison with previous results observed in other countries. In addition, the concept of incremental lifetime particulate matter exposure (ILPE) was employed to investigate the potential risks of exposure to particulate PAHs in Bangkok atmosphere.

47 CFR 74.1234 - Unattended operation.

Code of Federal Regulations, 2011 CFR

2011-10-01

..., AUXILIARY, SPECIAL BROADCAST AND OTHER PROGRAM DISTRIBUTIONAL SERVICES FM Broadcast Translator Stations and FM Broadcast Booster Stations § 74.1234 Unattended operation. (a) A station authorized under this...

Nutrient Concentrations, Loads, and Yields in the Eucha-Spavinaw Basin, Arkansas and Oklahoma, 2002-2004

USGS Publications Warehouse

Tortorelli, Robert L.

2006-01-01

The City of Tulsa, Oklahoma, uses Lake Eucha and Spavinaw Lake in the Eucha-Spavinaw basin in northwestern Arkansas and northeastern Oklahoma for public water supply. Taste and odor problems in the water attributable to blue-green algae have increased in frequency over time. Changes in the algae community in the lakes may be attributable to increases in nutrient levels in the lakes, and in the waters feeding the lakes. The U.S. Geological Survey, in cooperation with the City of Tulsa, conducted an investigation to summarize nitrogen and phosphorus concentrations and provide estimates of nitrogen and phosphorus loads, yields, and flow-weighted concentrations in the Eucha-Spavinaw basin for a 3-year period from January 2002 through December 2004. This report provides information needed to advance knowledge of the regional hydrologic system and understanding of hydrologic processes, and provides hydrologic data and results useful to multiple parties for interstate compacts. Nitrogen and phosphorus concentrations were significantly greater in runoff samples than in base-flow samples at Spavinaw Creek near Maysville, Arkansas; Spavinaw Creek near Colcord, Oklahoma, and Beaty Creek near Jay, Oklahoma. Runoff concentrations were not significantly greater than in base-flow samples at Spavinaw Creek near Cherokee, Arkansas; and Spavinaw Creek near Sycamore, Oklahoma. Nitrogen concentrations in base-flow samples significantly increased in the downstream direction in Spavinaw Creek from the Maysville to Sycamore stations then significantly decreased from the Sycamore to the Colcord stations. Nitrogen in base-flow samples from Beaty Creek was significantly less than in those from Spavinaw Creek. Phosphorus concentrations in base-flow samples significantly increased from the Maysville to Cherokee stations in Spavinaw Creek, probably due to a point source between those stations, then significantly decreased downstream from the Cherokee to Colcord stations. Phosphorus in base-flow samples from Beaty Creek was significantly less than phosphorus in base-flow samples from Spavinaw Creek downstream from the Maysville station. Nitrogen concentrations in runoff samples were not significantly different among the stations on Spavinaw Creek; however, the concentrations at Beaty Creek were significantly less than at all other stations. Phosphorus concentrations in runoff samples were not significantly different among the three downstream stations on Spavinaw Creek, and not significantly different at the Maysville station on Spavinaw Creek and the Beaty Creek station. Phosphorus and nitrogen concentrations in runoff samples from all stations generally increased with increasing streamflow. Estimated mean annual nitrogen total loads from 2002-2004 were substantially greater at the Spavinaw Creek stations than at Beaty Creek and increased in a downstream direction from Maysville to Colcord in Spavinaw Creek, with the load at the Colcord station about 2 times that of Maysville station. Estimated mean annual nitrogen base-flow loads at the Spavinaw Creek stations were about 5 to 11 times greater than base-flow loads at Beaty Creek. The runoff component of the annual nitrogen total load for Beaty Creek was 85 percent, whereas, at the Spavinaw Creek stations, the range in the runoff component was 60 to 66 percent. Estimated mean annual phosphorus total loads from 2002-2004 were greater at the Spavinaw Creek stations from Cherokee to Colcord than at Beaty Creek and increased in a downstream direction from Maysville to Colcord in Spavinaw Creek, with the load at the Colcord station about 2.5 times that of Maysville station. Estimated mean annual phosphorus base-flow loads at the Spavinaw Creek stations were about 2.5 to 19 times greater than at Beaty Creek. Phosphorus base-flow loads increased about 8 times from Maysville to Cherokee in Spavinaw Creek; the base-flow loads were about the same at the three downstream stations. The runoff component

Rapid Regional Centroid Solutions

NASA Astrophysics Data System (ADS)

Wei, S.; Zhan, Z.; Luo, Y.; Ni, S.; Chen, Y.; Helmberger, D. V.

2009-12-01

The 2008 Wells Nevada Earthquake was recorded by 164 broadband USArray stations within a distance of 550km (5 degrees) with all azimuths uniformly sampled. To establish the source parameters, we applied the Cut and Paste (CAP) code to all the stations to obtain a mechanism (strike/dip/rake=35/41/-85) at a depth of 9km and Mw=5.9. Surface wave shifts range from -8s to 8s which are in good agreement with ambient seismic noise (ASN) predictions. Here we use this data set to test the accuracy of the number of stations needed to obtain adequate solutions (position of the compressional and tension axis) for mechanism. The stations were chosen at random where combinations of Pnl and surface waves were used to establish mechanism and depth. If the event is bracketed by two stations, we obtain an accurate magnitude with good solutions about 80% of the trials. Complete solutions from four stations or Pnl from 10 stations prove reliable in nearly all situations. We also explore the use of this dataset in locating the event using a combination of surface wave travel times and/or the full waveform inversion (CAPloc) that uses the CAP shifts to refine locations. If the mechanism is known (fixed) only a few stations is needed to locate an event to within 5km if date is available at less than 150km. In contrast, surface wave travel times (calibrated to within one second) produce amazing accurate locations with only 6 stations reasonably distributed. It appears this approach is easily automated as suggested by Scrivner and Helmberger (1995) who discussed travel times of Pnl and surface waves and the evolving of source accuracy as the various phases arrive.

Long-term monitoring of persistent organic pollutants (POPs) at the Norwegian Troll station in Dronning Maud Land, Antarctica

NASA Astrophysics Data System (ADS)

Kallenborn, R.; Breivik, K.; Eckhardt, S.; Lunder, C. R.; Manø, S.; Schlabach, M.; Stohl, A.

2013-07-01

A first long-term monitoring of selected persistent organic pollutants (POPs) in Antarctic air has been conducted at the Norwegian research station Troll (Dronning Maud Land). As target contaminants 32 PCB congeners, α- and γ-hexachlorocyclohexane (HCH), trans- and cis-chlordane, trans- and cis-nonachlor, p,p'- and o,p-DDT, DDD, DDE as well as hexachlorobenzene (HCB) were selected. The monitoring program with weekly samples taken during the period 2007-2010 was coordinated with the parallel program at the Norwegian Arctic monitoring site (Zeppelin mountain, Ny-Ålesund, Svalbard) in terms of priority compounds, sampling schedule as well as analytical methods. The POP concentration levels found in Antarctica were considerably lower than Arctic atmospheric background concentrations. Similar to observations for Arctic samples, HCB is the predominant POP compound, with levels of around 22 pg m-3 throughout the entire monitoring period. In general, the following concentration distribution was found for the Troll samples analyzed: HCB > Sum HCH > Sum PCB > Sum DDT > Sum chlordanes. Atmospheric long-range transport was identified as a major contamination source for POPs in Antarctic environments. Several long-range transport events with elevated levels of pesticides and/or compounds with industrial sources were identified based on retroplume calculations with a Lagrangian particle dispersion model (FLEXPART).

Statistical analysis of oil percolation through pressboard measured by optical recording

NASA Astrophysics Data System (ADS)

Rogalski, Przemysław; Kozak, Czesław

2017-08-01

The paper presents a measuring station used to measure the percolation of transformer oil by electrotechnical pressboard. Nytro Taurus insulating oil manufactured by Nynas company percolation rate by the Pucaro company pressboard investigation was made. Approximately 60 samples of Pucaro made pressboard, widely used for insulation of power transformers, was measured. Statistical analysis of oil percolation times were performed. The measurements made it possible to determine the distribution of capillary diameters occurring in the pressboard.

47 CFR 74.793 - Digital low power TV and TV translator station protection of broadcast stations.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 47 Telecommunication 4 2010-10-01 2010-10-01 false Digital low power TV and TV translator station... DISTRIBUTIONAL SERVICES Low Power TV, TV Translator, and TV Booster Stations § 74.793 Digital low power TV and TV translator station protection of broadcast stations. (a) An application to construct a new digital low power...

An Adjoint-Based Analysis of the Sampling Footprints of Tall Tower, Aircraft and Potential Future Lidar Observations of CO2

NASA Technical Reports Server (NTRS)

Andrews, Arlyn; Kawa, Randy; Zhu, Zhengxin; Burris, John; Abshire, Jim

2004-01-01

A detailed mechanistic understanding of the sources and sinks of CO2 will be required to reliably predict future CO2 levels and climate. A commonly used technique for deriving information about CO2 exchange with surface reservoirs is to solve an 'inverse problem', where CO2 observations are used with an atmospheric transport model to find the optimal distribution of sources and sinks. Synthesis inversion methods are powerful tools for addressing this question, but the results are disturbingly sensitive to the details of the calculation. Studies done using different atmospheric transport models and combinations of surface station data have produced substantially different distributions of surface fluxes. Adjoint methods are now being developed that will more effectively incorporate diverse datasets in estimates of surface fluxes of CO2. In an adjoint framework, it will be possible to combine CO2 concentration data from longterm surface and aircraft monitoring stations with data from intensive field campaigns and with proposed future satellite observations. We have recently developed an adjoint for the GSFC 3-D Parameterized Chemistry and Transport Model (PCTM). Here, we will present results from a PCTM Adjoint study comparing the sampling footprints of tall tower, aircraft and potential future lidar observations of CO2. The vertical resolution and extent of the profiles and the observation frequency will be considered for several sites in North America.

Large-Scale Ichthyoplankton and Water Mass Distribution along the South Brazil Shelf

PubMed Central

de Macedo-Soares, Luis Carlos Pinto; Garcia, Carlos Alberto Eiras; Freire, Andrea Santarosa; Muelbert, José Henrique

2014-01-01

Ichthyoplankton is an essential component of pelagic ecosystems, and environmental factors play an important role in determining its distribution. We have investigated simultaneous latitudinal and cross-shelf gradients in ichthyoplankton abundance to test the hypothesis that the large-scale distribution of fish larvae in the South Brazil Shelf is associated with water mass composition. Vertical plankton tows were collected between 21°27′ and 34°51′S at 107 stations, in austral late spring and early summer seasons. Samples were taken with a conical-cylindrical plankton net from the depth of chlorophyll maxima to the surface in deep stations, or from 10 m from the bottom to the surface in shallow waters. Salinity and temperature were obtained with a CTD/rosette system, which provided seawater for chlorophyll-a and nutrient concentrations. The influence of water mass on larval fish species was studied using Indicator Species Analysis, whereas environmental effects on the distribution of larval fish species were analyzed by Distance-based Redundancy Analysis. Larval fish species were associated with specific water masses: in the north, Sardinella brasiliensis was found in Shelf Water; whereas in the south, Engraulis anchoita inhabited the Plata Plume Water. At the slope, Tropical Water was characterized by the bristlemouth Cyclothone acclinidens. The concurrent analysis showed the importance of both cross-shelf and latitudinal gradients on the large-scale distribution of larval fish species. Our findings reveal that ichthyoplankton composition and large-scale spatial distribution are determined by water mass composition in both latitudinal and cross-shelf gradients. PMID:24614798

Large-scale ichthyoplankton and water mass distribution along the South Brazil Shelf.

PubMed

de Macedo-Soares, Luis Carlos Pinto; Garcia, Carlos Alberto Eiras; Freire, Andrea Santarosa; Muelbert, José Henrique

2014-01-01

Ichthyoplankton is an essential component of pelagic ecosystems, and environmental factors play an important role in determining its distribution. We have investigated simultaneous latitudinal and cross-shelf gradients in ichthyoplankton abundance to test the hypothesis that the large-scale distribution of fish larvae in the South Brazil Shelf is associated with water mass composition. Vertical plankton tows were collected between 21°27' and 34°51'S at 107 stations, in austral late spring and early summer seasons. Samples were taken with a conical-cylindrical plankton net from the depth of chlorophyll maxima to the surface in deep stations, or from 10 m from the bottom to the surface in shallow waters. Salinity and temperature were obtained with a CTD/rosette system, which provided seawater for chlorophyll-a and nutrient concentrations. The influence of water mass on larval fish species was studied using Indicator Species Analysis, whereas environmental effects on the distribution of larval fish species were analyzed by Distance-based Redundancy Analysis. Larval fish species were associated with specific water masses: in the north, Sardinella brasiliensis was found in Shelf Water; whereas in the south, Engraulis anchoita inhabited the Plata Plume Water. At the slope, Tropical Water was characterized by the bristlemouth Cyclothone acclinidens. The concurrent analysis showed the importance of both cross-shelf and latitudinal gradients on the large-scale distribution of larval fish species. Our findings reveal that ichthyoplankton composition and large-scale spatial distribution are determined by water mass composition in both latitudinal and cross-shelf gradients.

A shared-world conceptual model for integrating space station life sciences telescience operations

NASA Technical Reports Server (NTRS)

Johnson, Vicki; Bosley, John

1988-01-01

Mental models of the Space Station and its ancillary facilities will be employed by users of the Space Station as they draw upon past experiences, perform tasks, and collectively plan for future activities. The operational environment of the Space Station will incorporate telescience, a new set of operational modes. To investigate properties of the operational environment, distributed users, and the mental models they employ to manipulate resources while conducting telescience, an integrating shared-world conceptual model of Space Station telescience is proposed. The model comprises distributed users and resources (active elements); agents who mediate interactions among these elements on the basis of intelligent processing of shared information; and telescience protocols which structure the interactions of agents as they engage in cooperative, responsive interactions on behalf of users and resources distributed in space and time. Examples from the life sciences are used to instantiate and refine the model's principles. Implications for transaction management and autonomy are discussed. Experiments employing the model are described which the authors intend to conduct using the Space Station Life Sciences Telescience Testbed currently under development at Ames Research Center.

Statistical analyses of the background distribution of groundwater solutes, Los Alamos National Laboratory, New Mexico.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Longmire, Patrick A.; Goff, Fraser; Counce, D. A.

2004-01-01

Background or baseline water chemistry data and information are required to distingu ish between contaminated and non-contaminated waters for environmental investigations conducted at Los Alamos National Laboratory (referred to as the Laboratory). The term 'background' refers to natural waters discharged by springs or penetrated by wells that have not been contaminated by LANL or other municipal or industrial activities, and that are representative of groundwater discharging from their respective aquifer material. These investigations are conducted as part of the Environmental Restoration (ER) Project, Groundwater Protection Program (GWPP), Laboratory Surveillance Program, the Hydrogeologic Workplan, and the Site-Wide Environmental Impact Statement (SWEIS).more » This poster provides a comprehensive, validated database of inorganic, organic, stable isotope, and radionuclide analyses of up to 136 groundwater samples collected from 15 baseline springs and wells located in and around Los Alamos National Laboratory, New Mexico. The region considered in this investigation extends from the western edge of the Jemez Mountains eastward to the Rio Grande and from Frijoles Canyon northward to Garcia Canyon. Figure 1 shows the fifteen stations sampled for this investigation. The sampling stations and associated aquifer types are summarized in Table 1.« less

Spatial and temporal trends of polycyclic aromatic hydrocarbons in wild mussels from the Cantabrian coast (N Spain) after the Prestige oil spill.

PubMed

Soriano, José Antonio; Viñas, Lucía; Franco, María Angeles; González, Juan José; Nguyen, Manh Hieu; Bayona, Josep María; Albaigés, Joan

2007-09-01

Polycyclic aromatic hydrocarbon (PAH) levels were determined in tissues of wild mussels (Mytilus galloprovincialis) collected at 17 stations along the Cantabrian coast (N Spain), from Navia (Asturias) to Fuenterrabía (Basque Country), in order to assess the extent of the environmental impact caused by the Prestige oil spill (November 13, 2002). Six sampling campaigns were carried out in April, June and November in 2003 and 2004. The comparison of PAH data with those obtained earlier in 2000 showed a widespread pyrolytic and petrogenic contamination and allowed an estimation, for the first time, of the background pollution in the region and identification of the chronic hotspots. The spatial distribution found in the first samples after the oil spill revealed the eastern area as the most affected due to the continuous arrival of fuel slicks since early summer 2003. Several stations in this area showed increased total PAH concentrations of up to 15 times the pre-spill levels, which did not recover until April 2004, more than one year after the accident. Molecular parameters within the aliphatic and aromatic fractions were determined to assess the presence of Prestige oil in these samples.

49 CFR 192.201 - Required capacity of pressure relieving and limiting stations.

Code of Federal Regulations, 2010 CFR

2010-10-01

... Design of Pipeline Components § 192.201 Required capacity of pressure relieving and limiting stations. (a) Each pressure relief station or pressure limiting station or group of those stations installed to... part of the pipeline or distribution system in excess of those for which it was designed, or against...

Distribution of the Fukushima-derived radionuclides in seawater in the Pacific off the coast of Miyagi, Fukushima, and Ibaraki Prefectures, Japan

NASA Astrophysics Data System (ADS)

Oikawa, S.; Takata, H.; Watabe, T.; Misonoo, J.; Kusakabe, M.

2013-03-01

The activities of artificial radionuclides in seawater samples collected off the coast of Miyagi, Fukushima, and Ibaraki Prefectures were measured as part of a monitoring program initiated by the Japanese government Ministry of Education, Sports, Science and Technology immediately after the Fukushima Dai-ichi nuclear power plant accident. The spatial and temporal distributions of those activities are summarized herein. The activities of strontium-90, iodine-131, cesium-134 and -137 (i.e. 90Sr, 131I, 134Cs, and 137Cs) derived from the accident were detected in seawater samples taken from areas of the coastal ocean adjacent to the power plant. No 131I was detected in surface waters (≤ 5 m depth) or in intermediate and bottom waters after 30 April 2011. Strontium-90 was found in surface waters collected from a few sampling stations in mid-August 2011 to mid-December 2011. Temporal changes of 90Sr activity in surface waters were evident, although the 90Sr activity at a given time varied widely between sampling stations. The activity of 90Sr in surface waters decreased slowly over time, and by the end of December 2011 had reached background levels recorded before the accident. Radiocesium, 134Cs and 137Cs, was found in seawater samples immediately after the accident. There was a remarkable change in 137Cs activities in surface waters during the first 7 months (March through September 2011) after the accident; the activity reached a maximum in the middle of April and thereafter decreased exponentially with time. Qualitatively, the distribution patterns in surface waters suggested that in early May 137Cs-polluted water was advected northward; some of the water then detached and was transported to the south. Two cores of the water with high 137Cs activity persisted at least until July 2011. In subsurface waters 137Cs activity was first detected in the beginning of April 2011, and the water masses were characterized by σt (an indicator of density) values of 25.5-26.5. From 9-14 May to 5-16 December 2011, the depths of the water masses increased with time, an indication that deepening of the isopycnals with time can be an important mechanism for the transport of 137Cs downward in coastal waters. During 4-21 February 2012, the water column became vertically homogeneous, probably because of convective mixing during the winter, the result being nearly constant values of 137Cs activity throughout the water column from the surface to the bottom (~200 m depth) at each station.

47 CFR 74.1202 - Frequency assignment.

Code of Federal Regulations, 2010 CFR

2010-10-01

..., AUXILIARY, SPECIAL BROADCAST AND OTHER PROGRAM DISTRIBUTIONAL SERVICES FM Broadcast Translator Stations and... translator station or for changes in the facilities of an authorized translator station shall endeavor to... will be assigned to each translator station. (b) Subject to compliance with all the requirements of...

Vertical zonation and distributions of calanoid copepods through the lower oxycline of the Arabian Sea oxygen minimum zone

NASA Astrophysics Data System (ADS)

Wishner, Karen F.; Gelfman, Celia; Gowing, Marcia M.; Outram, Dawn M.; Rapien, Mary; Williams, Rebecca L.

2008-08-01

This paper provides the first comprehensive analysis of calanoid copepod vertical zonation and community structure at midwater depths (300-1000 m) through the lower oxygen gradient (oxycline) (0.02 to ∼0.3 ml/L) of an oxygen minimum zone (OMZ). Feeding ecology was also analyzed. Zooplankton were collected with a double 1 m 2 MOCNESS plankton net in day and night vertically-stratified oblique tows from 1000 m to the surface at six stations during four seasons as part of the 1995 US Joint Global Ocean Flux Study (JGOFS) Arabian Sea project. The geographic comparison between a eutrophic more oxygenated onshore station and an offshore station with a strong OMZ served as a natural experiment to elucidate the influence of depth, oxygen concentration, season, food resources, and predators on the copepod distributions. Copepod species and species assemblages of the Arabian Sea OMZ differed in their spatial and vertical distributions relative to environmental and ecological characteristics of the water column and region. The extent and intensity of the oxycline at the lower boundary of the OMZ, and its spatial and temporal variability over the year of sampling, was an important factor affecting distributional patterns. Calanoid copepod species showed vertical zonation through the lower OMZ oxycline. Clustering analyses defined sample groups with similar copepod assemblages and species groups with similar distributions. No apparent diel vertical migration for either calanoid or non-calanoid copepods at these midwater depths was observed, but some species had age-related differences in vertical distributions. Subzones of the OMZ, termed the OMZ Core, the Lower Oxycline, and the Sub-Oxycline, had different copepod communities and ecological interactions. Major distributional and ecological changes were associated with surprisingly small oxygen gradients at low oxygen concentrations. The calanoid copepod community was most diverse in the most oxygenated environments (oxygen >0.14 ml/L), but the rank order of abundance of species was similar in the Lower Oxycline and Sub-Oxycline. Some species were absent or much scarcer in the OMZ Core. Two copepod species common in the Lower Oxycline were primarily detritivorous but showed dietary differences suggesting feeding specialization. The copepod Spinocalanus antarcticus fed primarily on components of the vertical particulate flux and suspended material, a less versatile diet than the co-occurring copepod Lucicutia grandis. Vertical zonation of copepod species through the lower OMZ oxycline is probably a complex interplay between physiological limitation by low oxygen, potential predator control, and potential food resources. Pelagic OMZ and oxycline communities, and their ecological interactions in the water column and with the benthos, may become even more widespread and significant in the future ocean, if global warming increases the extent and intensity of OMZs as predicted.

47 CFR 74.1269 - Copies of rules.

Code of Federal Regulations, 2011 CFR

2011-10-01

..., AUXILIARY, SPECIAL BROADCAST AND OTHER PROGRAM DISTRIBUTIONAL SERVICES FM Broadcast Translator Stations and FM Broadcast Booster Stations § 74.1269 Copies of rules. The licensee or permittee of a station...

Distinct Iron-binding Ligands in the Upper Water Column at Station ALOHA

NASA Astrophysics Data System (ADS)

Bundy, R.; Boiteau, R.; Repeta, D.

2016-02-01

The distribution and chemical properties of iron-binding organic ligands at station ALOHA were examined using a combination of solid phase extraction (SPE) followed by high pressure liquid chromatography-inductively coupled plasma mass spectrometry (HPLC-ICPMS). HPLC-ICPMS ligand measurements were complemented by competitive ligand exchange adsorptive cathodic stripping voltammetry (CLE-ACSV) analysis using salicylaldoxime as the added ligand. By HPLC-ICPMS, we find enhanced concentrations of distinct naturally-occurring polar iron-binding ligands present at the surface and in the chlorophyll maximum. Lower concentrations were found in the subsurface, where a suite of non-polar ligands was detected. Siderophores were present at the deepest depths sampled at station ALOHA, down to 400m. Incubation studies provided evidence for the production of iron-binding ligands associated with nutrient amended phytoplankton growth in surface waters, and as a result of microbial particle remineralization in the subsurface water column. Ligands classes identified via SPE were then compared to CLE-ACSV ligand measurements, as well as the conditional stability constants measured from model polar and non-polar siderophores, yielding insight to the sources of iron-binding ligands throughout the water column at station ALOHA.

Distribution of sewage indicated by Clostridium perfringens at a deep-water disposal site after cessation of sewage disposal.

PubMed

Hill, R T; Straube, W L; Palmisano, A C; Gibson, S L; Colwell, R R

1996-05-01

Clostridium perfringens, a marker of domestic sewage contamination, was enumerated in sediment samples obtained from the vicinity of the 106-Mile Site 1 month and 1 year after cessation of sewage disposal at this site. C. perfringens counts in sediments collected at the disposal site and from stations 26 nautical miles (ca. 48 km) and 50 nautical miles (ca. 92 km) to the southwest of the site were, in general, more than 10-fold higher than counts from an uncontaminated reference site. C. perfringens counts at the disposal site were not significantly different between 1992 and 1993, suggesting that sewage sludge had remained in the benthic environment at this site. At stations where C. perfringens counts were elevated (i.e., stations other than the reference station), counts were generally higher in the top 1 cm and decreased down to 5 cm. In some cases, C. perfringens counts in the bottom 4 or 5 cm showed a trend of higher counts in 1993 than in 1992, suggesting bioturbation. We conclude that widespread sludge contamination of the benthic environment has persisted for at least 1 year after cessation of ocean sewage disposal at the 106-Mile Site.

Rainfall, Streamflow, and Water-Quality Data During Stormwater Monitoring, Halawa Stream Drainage Basin, Oahu, Hawaii, July 1, 2005 to June 30, 2006

USGS Publications Warehouse

Presley, Todd K.; Jamison, Marcael T.J.; Young-Smith, Stacie T. M.

2006-01-01

Storm runoff water-quality samples were collected as part of the State of Hawaii Department of Transportation Stormwater Monitoring Program. This program is designed to assess the effects of highway runoff and urban runoff on Halawa Stream. For this program, rainfall data were collected at two stations, continuous discharge data at one station, continuous streamflow data at two stations, and water-quality data at five stations, which include the continuous discharge and streamflow stations. This report summarizes rainfall, discharge, streamflow, and water-quality data collected between July 1, 2005 and June 30, 2006. A total of 23 samples was collected over five storms during July 1, 2005 to June 30, 2006. The goal was to collect grab samples nearly simultaneously at all five stations, and flow-weighted time-composite samples at the three stations equipped with automatic samplers; however, all five storms were partially sampled owing to lack of flow at the time of sampling at some sites, or because some samples collected by the automatic sampler did not represent water from the storm. Samples were analyzed for total suspended solids, total dissolved solids, nutrients, chemical oxygen demand, and selected trace metals (cadmium, chromium, copper, lead, nickel, and zinc). Additionally, grab samples were analyzed for oil and grease, total petroleum hydrocarbons, fecal coliform, and biological oxygen demand. Quality-assurance/quality-control samples were also collected during storms and during routine maintenance to verify analytical procedures and check the effectiveness of equipment-cleaning procedures.

Kuipers replaces the ESEM-1 with new ESEM in the U.S. Laboratory

NASA Image and Video Library

2011-12-28

ISS030-E-033367 (28 Dec. 2011) --- In the International Space Station?s Destiny laboratory, European Space Agency astronaut Andre Kuipers, Expedition 30 flight engineer, replaces the faulty Exchangeable Standard Electronic Module 1 (ESEM-1) behind the front panel of the Microgravity Science Glovebox Remote Power Distribution Assembly (MSG RPDA) with the new spare. The ESEM is used to distribute station main power to the entire MSG facility.

Spatial and temporal infaunal dynamics of the Blanes submarine canyon-slope system (NW Mediterranean); changes in nematode standing stocks, feeding types and gender-life stage ratios

NASA Astrophysics Data System (ADS)

Ingels, Jeroen; Vanreusel, Ann; Romano, Chiara; Coenjaerts, Johan; Mar Flexas, M.; Zúñiga, Diana; Martin, Daniel

2013-11-01

Despite recent advances in the knowledge of submarine canyons ecosystems, our understanding of the faunal patterns and processes in these environments is still marginal. In this study, meiobenthic nematode communities (from 300 m to 1600 m depth) obtained in November 2003 and May 2004 at eight stations inside and outside Blanes submarine canyon were analysed for nematode standing stocks (SSs), feeding types and gender-life stage distributions. Environmental data were obtained by sediment traps and current meters, attached to moorings (April 2003-May 2004), and sediments samples analysed for biogeochemistry and grain size (May 2004). In November 2003, nematode SSs decreased with increasing depth (367.2 individuals and 7.31 μg C per 10 cm2 at 388 m water depth to 7.7 individuals and 0.18 μg C per 10 cm2 at 1677 m water depth), showing a significant negative relation (abundance: R2 = 0.620, p = 0.020; biomass: R2 = 0.512, p = 0.046). This was not the case in May 2004 (283.5 individuals and 3.53 μg C per 10 cm2 at 388 m water depth to 490.8 individuals and 4.93 μg C per 10 cm2 at 1677 m water depth; abundance: R2 = 0.003, p = 0.902; biomass: R2 = 0.052, p = 0.587), suggesting a temporal effect that overrides the traditional decrease of SSs with increasing water depth. Both water depth and sampling time played a significant role in explaining nematode SSs, but with differences between stations. No overall differences were observed between canyon and open slope stations. Nematode standing stock (SS) patterns can be explained by taking into account the interplay of phytodetrital input and disturbance events, with station differences such as topography playing an important role. Individual nematode size decreased from November 2003 to May 2004 and was explained by a food-induced genera shift and/or a food-induced transition from a ‘latent’ to a ‘reproductive’ nematode community. Our results suggest that size patterns in nematode communities are not solely governed by trophic conditions over longer periods of time in relatively food-rich environments such as canyons. We hypothesize that food pulses in a dynamic and topographical heterogeneous environment such as canyons regulate nematode size distributions, rather than long-term food availability. Feeding type distributions in the Blanes Canyon did not clearly resemble those from other canyon systems, apart from the spring assemblage at one station in the head of the canyon.

Impact of refined petroleum spills on water quality, macro-invertebrate and microbial communities of a tropical aquatic environment.

PubMed

Chukwu, L O; Nwachukwu, S C U

2005-07-01

Water quality characteristics, benthic macro-invertebrates and microbial communities of three first order streams in South West Nigeria were investigated to assess the effects of refined petroleum five months after spillage. All physical and chemical conditions except temperature and pH were significantly different (P<0.01) at the upstream control stations and impacted stations reflecting the perturbational stress. The benthic macro-invertebrate fauna were dominated by arthropods, but the faunal spectrum was dissimilar at all the stations studied. Sampling stations at the epicentre of the spill showed considerable reduction in faunal compositions and relative abundance. Generally, the microbial density and diversity were highest in both soil and water samples from impacted sites than in control sites. There was a significantly higher proportion (P < 0.05) of hydrocarbon utilizers in soil than in water samples in all stations except in samples from stations (P<0.05).

Evaluation and trends of land cover, streamflow, and water quality in the North Canadian River Basin near Oklahoma City, Oklahoma, 1968–2009

USGS Publications Warehouse

Esralew, Rachel A.; Andrews, William J.; Smith, S. Jerrod

2011-01-01

The U.S. Geological Survey, in cooperation with the city of Oklahoma City, collected water-quality samples from the North Canadian River at the streamflow-gaging station near Harrah, Oklahoma (Harrah station), since 1968, and at an upstream streamflow-gaging station at Britton Road at Oklahoma City, Oklahoma (Britton Road station), since 1988. Statistical summaries and frequencies of detection of water-quality constituent data from water samples, and summaries of water-quality constituent data from continuous water-quality monitors are described from the start of monitoring at those stations through 2009. Differences in concentrations between stations and time trends for selected constituents were evaluated to determine the effects of: (1) wastewater effluent discharges, (2) changes in land-cover, (3) changes in streamflow, (4) increases in urban development, and (5) other anthropogenic sources of contamination on water quality in the North Canadian River downstream from Oklahoma City. Land-cover changes between 1992 and 2001 in the basin between the Harrah station and Lake Overholser upstream included an increase in developed/barren land-cover and a decrease in pasture/hay land cover. There were no significant trends in median and greater streamflows at either streamflow-gaging station, but there were significant downward trends in lesser streamflows, especially after 1999, which may have been associated with decreases in precipitation between 1999 and 2009 or construction of low-water dams on the river upstream from Oklahoma City in 1999. Concentrations of dissolved chloride, lead, cadmium, and chlordane most frequently exceeded the Criterion Continuous Concentration (a water-quality standard for protection of aquatic life) in water-quality samples collected at both streamflow-gaging stations. Visual trends in annual frequencies of detection were investigated for selected pesticides with frequencies of detection greater than 10 percent in all water samples collected at both streamflow-gaging stations. Annual frequencies of detection of 2,4-dichlorophenoxyacetic acid and bromacil increased with time. Annual frequencies of detection of atrazine, chlorpyrifos, diazinon, dichlorprop, and lindane decreased with time. Dissolved nitrogen and phosphorus concentrations were significantly greater in water samples collected at the Harrah station than at the Britton Road station, whereas specific conductance was greater at the Britton Road station. Concentrations of dissolved oxygen, biochemical oxygen demand, and fecal coliform bacteria were not significantly different between stations. Daily minimum, mean, and maximum specific conductance collected from continuous water-quality monitors were significantly greater at the Britton Road station than in water samples collected at the Harrah station. Daily minimum, maximum, and diurnal fluctuations of water temperature collected from continuous water-quality monitors were significantly greater at the Harrah station than at the Britton Road station. The daily maximums and diurnal range of dissolved oxygen concentrations were significantly greater in water samples collected at the Britton Road station than at the Harrah station, but daily mean dissolved oxygen concentrations in water at those streamflow-gaging stations were not significantly different. Daily mean and diurnal water temperature ranges increased with time at the Britton Road and Harrah streamflow-gaging stations, whereas daily mean and diurnal specific conductance ranges decreased with time at both streamflow-gaging stations from 1988–2009. Daily minimum dissolved oxygen concentrations collected from continuous water-quality monitors more frequently indicated hypoxic conditions at the Harrah station than at the Britton Road station after 1999. Fecal coliform bacteria counts in water decreased slightly from 1988–2009 at the Britton Road station. The Seasonal Kendall's tau test indicated significant downward trends in

An automated system for the study of ionospheric spatial structures

NASA Astrophysics Data System (ADS)

Belinskaya, I. V.; Boitman, O. N.; Vugmeister, B. O.; Vyborova, V. M.; Zakharov, V. N.; Laptev, V. A.; Mamchenko, M. S.; Potemkin, A. A.; Radionov, V. V.

The system is designed for the study of the vertical distribution of electron density and the parameters of medium-scale ionospheric irregularities over the sounding site as well as the reconstruction of the spatial distribution of electron density within the range of up to 300 km from the sounding location. The system comprises an active central station as well as passive companion stations. The central station is equipped with the digital ionosonde ``Basis'', the measuring-and-computing complex IVK-2, and the receiver-recorder PRK-3M. The companion stations are equipped with receivers-recorders PRK-3. The automated comlex software system includes 14 subsystems. Data transfer between them is effected using magnetic disk data sets. The system is operated in both ionogram mode and Doppler shift and angle-of-arrival mode. Using data obtained in these two modes, the reconstruction of the spatial distribution of electron density in the region is carried out. Reconstruction is checked for accuracy using data from companion stations.

Incorporating Nonstationarity into IDF Curves across CONUS from Station Records and Implications

NASA Astrophysics Data System (ADS)

Wang, K.; Lettenmaier, D. P.

2017-12-01

Intensity-duration-frequency (IDF) curves are widely used for engineering design of storm-affected structures. Current practice is that IDF-curves are based on observed precipitation extremes fit to a stationary probability distribution (e.g., the extreme value family). However, there is increasing evidence of nonstationarity in station records. We apply the Mann-Kendall trend test to over 1000 stations across the CONUS at a 0.05 significance level, and find that about 30% of stations test have significant nonstationarity for at least one duration (1-, 2-, 3-, 6-, 12-, 24-, and 48-hours). We fit the stations to a GEV distribution with time-varying location and scale parameters using a Bayesian- methodology and compare the fit of stationary versus nonstationary GEV distributions to observed precipitation extremes. Within our fitted nonstationary GEV distributions, we compare distributions with a time-varying location parameter versus distributions with both time-varying location and scale parameters. For distributions with two time-varying parameters, we pay particular attention to instances where location and scale trends have opposing directions. Finally, we use the mathematical framework based on work of Koutsoyiannis to generate IDF curves based on the fitted GEV distributions and discuss the implications that using time-varying parameters may have on simple scaling relationships. We apply the above methods to evaluate how frequency statistics based on a stationary assumption compare to those that incorporate nonstationarity for both short and long term projects. Overall, we find that neglecting nonstationarity can lead to under- or over-estimates (depending on the trend for the given duration and region) of important statistics such as the design storm.

Occurrence, distribution, and transport of pesticides, trace elements, and selected inorganic constituents into the Salton Sea Basin, California, 2001-2002

USGS Publications Warehouse

LeBlanc, Lawrence A.; Schroeder, Roy A.; Orlando, James L.; Kuivila, Kathyrn M.

2004-01-01

A study of pesticide distribution and transport within the Salton Sea Basin, California, was conducted from September 2001 to October 2002. Sampling for the study was done along transects for the three major rivers that flow into the Salton Sea Basin: the New and Alamo Rivers at the southern end of the basin and the Whitewater River at the northern end. Three stations were established on each river: an outlet station approximately 1 mile upstream of the river discharge, a near-shore station in the river delta, and off-shore station in the Salton Sea. Water and suspended and bed sediments were collected at each station in October 2001, March-April 2002, and September 2002, coinciding with peak pesticide applications in the fall and spring. Fourteen current-use pesticides were detected in the water column. Concentrations of dissolved pesticides typically decreased from the outlets to the sea in all three rivers, consistent with the off-shore transport of pesticides from the rivers to the sea. Dissolved concentrations ranged from the limits of detection to 151 nanograms per liter (ng/L); however, diazinon, eptam (EPTC), and malathion were detected at much higher concentrations (940?3,830 ng/L) at the New and Alamo River outlet and near-shore stations. Concentrations of carbaryl, dacthal, diazinon, and eptam were higher during the two fall sampling periods, whereas concentrations of atrazine, carbofuran, and trifluralin were higher during the spring. Current-use pesticides also were detected on suspended and bed sediments in concentrations ranging from method detection limits to 106 ng/g (nanograms per gram). Chlorpyrifos, dacthal, eptam, trifluralin, and DDE were the most frequently detected pesticides on sediments from all three rivers. The number and concentrations of pesticides associated with suspended sediments frequently were similar for the river outlet and near-shore sites, consistent with the downstream transport of sediment-associated pesticides out of the rivers. Seasonal trends in pesticide concentration were similar to those for dissolved concentrations in fall 2001 and spring 2002, but not in fall 2002. Generally, the pesticides detected in the suspended sediments were the same pesticides detected in the bed sediments, and concentrations were similar, especially at the Alamo River outlet site in spring 2002 and fall 2002. Pesticides generally were not detected in sediments from the off-shore sites; however, the samples from these sites also had greater incidences of matrix interference during analysis. Sediment-associated pesticide concentrations were above equilibrium in water, suggesting a bound fraction of sediment-associated pesticides that are resistant to desorption. Concentrations of trace elements and other inorganic constituents in suspended sediments collected during the fall 2001 followed expected trends with dilution of river-derived minerals owing to highly organic autochthonous production within the Salton Sea Basin. However, calculation of enrichment ratios provided evidence for the bioconcentration of several trace elements, notably selenium in the off-shore biota.

Hydrocarbon contamination of coastal sediments from the Sfax area (Tunisia), Mediterranean Sea.

PubMed

Louati, A; Elleuch, B; Kallel, M; Saliot, A; Dagaut, J; Oudot, J

2001-06-01

The coastal area off the city of Sfax (730,000 inhabitants), well-known for fisheries and industrial activities, receives high inputs of organic matter mostly anthropogenic. Eighteen stations were selected in the vicinity of the direct discharge of industrial sewage effluents in the sea in order to study the spatial distribution of the organic contamination. Surface sediments sampled in the shallow shelf were analysed for hydrocarbons by Fourier transform infrared spectroscopy, gas chromatography and gas chromatography/mass spectrometry. Total hydrocarbon distributions revealed high contamination as compared to other coastal Mediterranean sites, with an average concentration of 1865 ppm/dry weight sediment. Gas chromatographic distribution patterns, values of unresolved mixture/n-alkane ratio and distributions of steranes and hopanes confirmed a petroleum contamination of the Arabian light crude oil type. Biogenic compounds were also identified with a series of short-chain carbon-numbered n-alkenes in the carbon range 16-24.

Spatial and temporal distribution of platinum, palladium and rhodium in Zagreb air.

PubMed

Rinkovec, Jasmina; Pehnec, Gordana; Godec, Ranka; Davila, Silvije; Bešlić, Ivan

2018-09-15

Platinum (Pt), palladium (Pd) and rhodium (Rh) are most widely used in the production of automotive catalytic converters that serve to reduce toxic emissions from motor vehicles. The aim of this study was to quantitatively determine the levels of platinum, palladium and rhodium in the PM 10 and PM 2.5 fraction of airborne particle matter and find their spatial and temporal distribution at different polluted areas of the city of Zagreb, Croatia. The method used in this paper included weekly sampling of airborne particle matter on quartz filters, microwave digestion in acid under high pressure and temperature, and analysis by inductively coupled plasma mass spectrometry (ICP MS). The results have shown that the highest mean values at all three sampling stations (North, Center, South) were obtained for palladium (3.856 pg m -3 , 5.396 pg m -3 , 5.600 pg m -3 ) and the lowest for rhodium (0.444 pg m -3 , 0.643 pg m -3 , 0.750 pg m -3 ). The average mass concentrations of platinum group elements (PGE) in PM 10 increased for all three elements in the direction North < Center < South which had to do with the traffic load nearby the monitoring stations. The ratio of measured mass concentrations to all measuring stations was similar to platinum, palladium and rhodium content in automotive catalytic converters. Factor analysis grouped platinum, palladium and rhodium at all of the monitoring stations, and their relation to other metals together with the aforementioned results indicate that their main source of pollution is traffic or precisely automotive catalytic converters. At all three of the monitoring sites, higher values were measured during the colder part of the year. The results of measuring platinum, palladium and rhodium levels in the city of Zagreb are the first results of their kind for this area and will provide insights into the contribution of catalytic converters to the presence of these elements in the environment. Copyright © 2018 Elsevier B.V. All rights reserved.

Distributed operating system for NASA ground stations

NASA Technical Reports Server (NTRS)

Doyle, John F.

1987-01-01

NASA ground stations are characterized by ever changing support requirements, so application software is developed and modified on a continuing basis. A distributed operating system was designed to optimize the generation and maintenance of those applications. Unusual features include automatic program generation from detailed design graphs, on-line software modification in the testing phase, and the incorporation of a relational database within a real-time, distributed system.

A modular Space Station/Base electrical power system - Requirements and design study.

NASA Technical Reports Server (NTRS)

Eliason, J. T.; Adkisson, W. B.

1972-01-01

The requirements and procedures necessary for definition and specification of an electrical power system (EPS) for the future space station are discussed herein. The considered space station EPS consists of a replaceable main power module with self-contained auxiliary power, guidance, control, and communication subsystems. This independent power source may 'plug into' a space station module which has its own electrical distribution, control, power conditioning, and auxiliary power subsystems. Integration problems are discussed, and a transmission system selected with local floor-by-floor power conditioning and distribution in the station module. This technique eliminates the need for an immediate long range decision on the ultimate space base power sources by providing capability for almost any currently considered option.

Increased Fire and Toxic Contaminant Detection Responsibility by Use of Distributed, Aspirating Sensors

NASA Technical Reports Server (NTRS)

Youngblood, Wallace W.

1990-01-01

Viewgraphs of increased fire and toxic contaminant detection responsivity by use of distributed, aspirating sensors for space station are presented. Objectives of the concept described are (1) to enhance fire and toxic contaminant detection responsivity in habitable regions of space station; (2) to reduce system weight and complexity through centralized detector/monitor systems; (3) to increase fire signature information from selected locations in a space station module; and (4) to reduce false alarms.

Evaluation of emergency drug releases from the Centers for Disease Control and Prevention Quarantine Stations

PubMed Central

Roohi, Shahrokh; Grinnell, Margaret; Sandoval, Michelle; Cohen, Nicole J.; Crocker, Kimberly; Allen, Christopher; Dougherty, Cindy; Jolly, Julian; Pesik, Nicki

2018-01-01

The Centers for Disease Control and Prevention (CDC) Quarantine Stations distribute select lifesaving drug products that are not commercially available or are in limited supply in the United States for emergency treatment of certain health conditions. Following a retrospective analysis of shipment records, the authors estimated an average of 6.66 hours saved per shipment when drug products were distributed from quarantine stations compared to a hypothetical centralized site from CDC headquarters in Atlanta, GA. This evaluation supports the continued use of a decentralized model which leverages CDC's regional presence and maximizes efficiency in the distribution of lifesaving drugs. PMID:25779896

Evaluation of emergency drug releases from the Centers for Disease Control and Prevention Quarantine Stations.

PubMed

Roohi, Shahrokh; Grinnell, Margaret; Sandoval, Michelle; Cohen, Nicole J; Crocker, Kimberly; Allen, Christopher; Dougherty, Cindy; Jolly, Julian; Pesik, Nicki

2015-01-01

The Centers for Disease Control and Prevention (CDC) Quarantine Stations distribute select lifesaving drug products that are not commercially available or are in limited supply in the United States for emergency treatment of certain health conditions. Following a retrospective analysis of shipment records, the authors estimated an average of 6.66 hours saved per shipment when drug products were distributed from quarantine stations compared to a hypothetical centralized site from CDC headquarters in Atlanta, GA. This evaluation supports the continued use of a decentralized model which leverages CDC's regional presence and maximizes efficiency in the distribution of lifesaving drugs.

Static analysis of rectifier cabinet for nuclear power generating stations based on finite element method

NASA Astrophysics Data System (ADS)

Yin, Qiang; Chen, Tian-jin; Li, Wei-yang; Xiong, Ze-cheng; Ma, Rui

2017-09-01

In order to obtain the deformation map and equivalent stress distribution of rectifier cabinet for nuclear power generating stations, the quality distribution of structure and electrical are described, the tensile bond strengths of the rings are checked, and the finite element model of cabinet is set up by ANSYS. The transport conditions of the hoisting state and fork loading state are analyzed. The deformation map and equivalent stress distribution are obtained. The attentive problems are put forward. It is a reference for analysis method and the obtained results for the transport of rectifier cabinet for nuclear power generating stations.

Space Station environmental control and life support system distribution and loop closure studies

NASA Technical Reports Server (NTRS)

Humphries, William R.; Reuter, James L.; Schunk, Richard G.

1986-01-01

The NASA Space Station's environmental control and life support system (ECLSS) encompasses functional elements concerned with temperature and humidity control, atmosphere control and supply, atmosphere revitalization, fire detection and suppression, water recovery and management, waste management, and EVA support. Attention is presently given to functional and physical module distributions of the ECLSS among these elements, with a view to resource requirements and safety implications. A strategy of physical distribution coupled with functional centralization is for the air revitalization and water reclamation systems. Also discussed is the degree of loop closure desirable in the initial operational capability status Space Station's oxygen and water reclamation loops.

Aerosol formation and distribution in the Arctic during AGASP-II, March-April 1986

NASA Technical Reports Server (NTRS)

Schnell, Russell C.; Kahl, Jonathan D.; Herbert, Gary A.; Bodhaine, B. A.; Bridgman, Howard A.

1988-01-01

The Arctic Gas and Aerosol Sampling Program has undertaken the determination of the distribution, transport, chemistry, aerosol physics, and radiative effects of the 'Arctic haze' air-pollution phenomenon. Attention has been given the April 2-3, 1986 haze zone, with large condensation nuclei, SO2, and soot-carbon concentrations, which appeared near the Barrow Baseline Station. The composite trajectory of the haze zone has been determined, as has its probable source region. After travelling 10,000 km, the haze still had SO2, aerosol black carbon, and condensation nuclei concentrations in excess of those measured off the East Coast of the U.S. in January of the same year.

Methods for estimating the magnitude and frequency of peak discharges of rural, unregulated streams in Virginia

USGS Publications Warehouse

Bisese, James A.

1995-01-01

Methods are presented for estimating the peak discharges of rural, unregulated streams in Virginia. A Pearson Type III distribution is fitted to the logarithms of the unregulated annual peak-discharge records from 363 stream-gaging stations in Virginia to estimate the peak discharge at these stations for recurrence intervals of 2 to 500 years. Peak-discharge characteristics for 284 unregulated stations are divided into eight regions based on physiographic province, and regressed on basin characteristics, including drainage area, main channel length, main channel slope, mean basin elevation, percentage of forest cover, mean annual precipitation, and maximum rainfall intensity. Regression equations for each region are computed by use of the generalized least-squares method, which accounts for spatial and temporal correlation between nearby gaging stations. This regression technique weights the significance of each station to the regional equation based on the length of records collected at each cation, the correlation between annual peak discharges among the stations, and the standard deviation of the annual peak discharge for each station.Drainage area proved to be the only significant explanatory variable in four regions, while other regions have as many as three significant variables. Standard errors of the regression equations range from 30 to 80 percent. Alternate equations using drainage area only are provided for the five regions with more than one significant explanatory variable.Methods and sample computations are provided to estimate peak discharges at gaged and engaged sites in Virginia for recurrence intervals of 2, 5, 10, 25, 50, 100, 200, and 500 years, and to adjust the regression estimates for sites on gaged streams where nearby gaging-station records are available.

Distribution and growth of salps in a Kuroshio warm-core ring during summer 1987

NASA Astrophysics Data System (ADS)

Tsuda, Atsushi; Nemoto, Takahisa

1992-03-01

A salp bloom, accounting for 47% of the macrozooplankton wet weight in the upper 200 m, was observed in a Kuroshio warm-core ring and adjacent areas during September 1987. Although salps had wide distribution and high biomass in the ring and adjacent southern areas, they did not occur north of the northern ring front. Thalia democratica dominated in these areas and Salpa fusiformis was abundant at some stations. Salps were distributed only in the upper 200 m of the water column. The maximum abundance of T. democratica was in the surface mixed layer, 0-20 m. S. fusiformis was most abundant from 50 to 75 m. Diel vertical migration was observed only for solitary zooids of S. fusiformis. All other salps appeared only on the surface. The growth of aggregate zooids of T. democratica was investigated with the time-series sampling during a 28-h sampling period following a drifter. Several cohorts were identified in the length-frequency distributions. The average relative growth rate in length was 8.0% per hour. Carbon consumption by the T. democratica population, calculated from the derived growth rate, suggested that T. democratica was a major consumer of the primary production in the ring.

Man-systems distributed system for Space Station Freedom

NASA Technical Reports Server (NTRS)

Lewis, J. L.

1990-01-01

Viewgraphs on man-systems distributed system for Space Station Freedom are presented. Topics addressed include: description of man-systems (definition, requirements, scope, subsystems, and topologies); implementation (approach, tools); man-systems interfaces (system to element and system to system); prime/supporting development relationship; selected accomplishments; and technical challenges.

The TAIGA timing array HiSCORE - first results

NASA Astrophysics Data System (ADS)

Tluczykont, M.; Budnev, N.; Astapov, I.; Barbashina, N.; Bogdanov, A.; Boreyko, V.; Brückner, M.; Chiavassa, A.; Chvalaev, O.; Gress, O.; Gress, T.; Grishin, O.; Dyachok, A.; Epimakhov, S.; Fedorov, O.; Gafarov, A.; Gorbunov, N.; Grebenyuk, V.; Grinuk, A.; Horns, D.; Kalinin, A.; Karpov, N.; Kalmykov, N.; Kazarina, Y.; Kiryuhin, S.; Kokoulin, R.; Kompaniets, K.; Konstantinov, A.; Korosteleva, E.; Kozhin, V.; Kravchenko, E.; Kunnas, M.; Kuzmichev, L.; Lemeshev, Yu.; Lubsandorzhiev, B.; Lubsandorzhiev, N.; Mirgazov, R.; Mirzoyan, R.; Monkhoev, R.; Nachtigall, R.; Osipova, E.; Pakhorukov, A.; Panasyuk, M.; Pankov, L.; Petrukhin, A.; Poleschuk, V.; Popova, E.; Porelli, A.; Postnikov, E.; Prosin, V.; Ptuskin, V.; Rubtsov, G.; Pushnin, A.; Samoliga, V.; Satunin, P.; Semeney, Yu.; Silaev, A.; Silaev, A.; Skurikhin, A.; Slunecka, M.; Sokolov, A.; Spiering, C.; Sveshnikova, L.; Tabolenko, V.; Tarashansky, B.; Tkachenko, A.; Tkachev, L.; Voronin, D.; Wischnewski, R.; Zagorodnikov, A.; Zurbanov, V.; Zhurov, D.; Yashin, I.

2017-03-01

Observations of gamma rays up to several 100 TeV are particularly important to spectrally resolve the cutoff regime of the long-sought Pevatrons, the cosmic-ray PeV accelerators. One component of the TAIGA hybrid detector is the TAIGA-HiSCORE timing array, which currently consists of 28 wide angle (0.6 sr) air Cherenkov timing stations distributed on an area of 0.25 km2. The HiSCORE concept is based on (non-imaging) air shower front sampling with Cherenkov light. First results are presented.

47 CFR 74.780 - Broadcast regulations applicable to translators, low power, and booster stations.

Code of Federal Regulations, 2013 CFR

2013-10-01

..., low power, and booster stations. 74.780 Section 74.780 Telecommunication FEDERAL COMMUNICATIONS... PROGRAM DISTRIBUTIONAL SERVICES Low Power TV, TV Translator, and TV Booster Stations § 74.780 Broadcast regulations applicable to translators, low power, and booster stations. The following rules are applicable to...

47 CFR 74.780 - Broadcast regulations applicable to translators, low power, and booster stations.

Code of Federal Regulations, 2012 CFR

2012-10-01

..., low power, and booster stations. 74.780 Section 74.780 Telecommunication FEDERAL COMMUNICATIONS... PROGRAM DISTRIBUTIONAL SERVICES Low Power TV, TV Translator, and TV Booster Stations § 74.780 Broadcast regulations applicable to translators, low power, and booster stations. The following rules are applicable to...

47 CFR 74.780 - Broadcast regulations applicable to translators, low power, and booster stations.

Code of Federal Regulations, 2014 CFR

2014-10-01

..., low power, and booster stations. 74.780 Section 74.780 Telecommunication FEDERAL COMMUNICATIONS... PROGRAM DISTRIBUTIONAL SERVICES Low Power TV, TV Translator, and TV Booster Stations § 74.780 Broadcast regulations applicable to translators, low power, and booster stations. The following rules are applicable to...

49 CFR 192.741 - Pressure limiting and regulating stations: Telemetering or recording gauges.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 49 Transportation 3 2010-10-01 2010-10-01 false Pressure limiting and regulating stations... STANDARDS Maintenance § 192.741 Pressure limiting and regulating stations: Telemetering or recording gauges. (a) Each distribution system supplied by more than one district pressure regulating station must be...

Deep-Sea Macrobenthos Community Structure Proximal to the 2010 Macondo Well Blowout (2010-2011)

NASA Astrophysics Data System (ADS)

Briggs, K. B.; Brunner, C. A.; Yeager, K. M.

2017-12-01

Macrobenthos, polycyclic aromatic hydrocarbons (PAH) and sedimentary organic carbon (SOC) were sampled by multicorer in the vicinity of the Deepwater Horizon well head in October 2010 and 2011 to assess the effects of the April 2010 spill. Four stations were sampled east of the well head, four stations were sampled west of the well head, and "control" stations were sampled 58 and 65 km to the southwest. The macrobenthos community, as expected for continental slope/bathyal (water depth 1160-1760 m) benthos, was highly diverse. Polychaetes dominated at all stations, with either crustaceans or mollusks comprising the next most abundant taxon. The stations within five km of the well head showed slightly lower diversity than the more distal stations six months after the blowout. Compared to the "control" station, proportions of suspension feeders were generally depressed at stations with high PAH concentrations. Anomalously high values for abundance and diversity (and PAH) were found at one station 20 km west of the well head. The median body size of macrobenthos was negatively correlated with total PAH concentration, with 74% of the variation in median size explained by variation in PAH, when the anomalous station was excluded. Macrobenthos abundance did not appear to be influenced by SOC. Abundance and diversity of the macrobenthos was generally higher 18 months after the blowout, with measured PAH concentrations diminished to below background level.

Rainfall, Streamflow, and Water-Quality Data During Stormwater Monitoring, Halawa Stream Drainage Basin, Oahu, Hawaii, July 1, 2006 to June 30, 2007

USGS Publications Warehouse

Young, Stacie T.M.; Jamison, Marcael T.J.

2007-01-01

Storm runoff water-quality samples were collected as part of the State of Hawaii Department of Transportation Stormwater Monitoring Program. This program is designed to assess the effects of highway runoff and urban runoff on Halawa Stream. For this program, rainfall data were collected at two stations, continuous streamflow data at three stations, and water-quality data at five stations, which include the two continuous streamflow stations. This report summarizes rainfall, streamflow, and water-quality data collected between July 1, 2006 and June 30, 2007. A total of 13 samples was collected over two storms during July 1, 2006 to June 30, 2007. The goal was to collect grab samples nearly simultaneously at all five stations and flow-weighted time-composite samples at the three stations equipped with automatic samplers. Samples were analyzed for total suspended solids, total dissolved solids, nutrients, chemical oxygen demand, and selected trace metals (cadmium, chromium, copper, lead, nickel, and zinc). Additionally, grab samples were analyzed for oil and grease, total petroleum hydrocarbons, fecal coliform, and biological oxygen demand. Quality-assurance/quality-control samples were also collected during storms and during routine maintenance to verify analytical procedures and check the effectiveness of equipment-cleaning procedures.

A Distributed Simulation Facility to Support Human Factors Research in Advanced Air Transportation Technology

NASA Technical Reports Server (NTRS)

Amonlirdviman, Keith; Farley, Todd C.; Hansman, R. John, Jr.; Ladik, John F.; Sherer, Dana Z.

1998-01-01

A distributed real-time simulation of the civil air traffic environment developed to support human factors research in advanced air transportation technology is presented. The distributed environment is based on a custom simulation architecture designed for simplicity and flexibility in human experiments. Standard Internet protocols are used to create the distributed environment, linking all advanced cockpit simulator, all Air Traffic Control simulator, and a pseudo-aircraft control and simulation management station. The pseudo-aircraft control station also functions as a scenario design tool for coordinating human factors experiments. This station incorporates a pseudo-pilot interface designed to reduce workload for human operators piloting multiple aircraft simultaneously in real time. The application of this distributed simulation facility to support a study of the effect of shared information (via air-ground datalink) on pilot/controller shared situation awareness and re-route negotiation is also presented.

Role of Sediments and Nutrients in the Condition of a Coral Reef Under Tourist Pressure: Akumal México.

NASA Astrophysics Data System (ADS)

Naranjo-Garcia, M. J.; Vadés Lozano, D. S.; Real-De-Leon, E.; Lopez-Aguiar, K.; Garza-Perez, J. R.

2014-12-01

Akumal, Mexico, was the first tourist resort in the Mexican Caribbean mainland, its highly developed coastal zone lies directly above the phreatic, and it is directly connected to the sub-littoral waters. Akumal is also known as a well-developed fringing coral reef, now in a critical condition. The main objective of this study was to explore the relationship between two of the main indicators of human pressure (nutrients and sedimentation, linked to coastal development and water run-offs) and the condition of the reef benthos, during a year. The sampling design used four transects perpendicular to shore, associated to different tourist and water run-off exposure, for a total of 12 stations distributed in three different reef zones (transition zone, shallow and deep spurs and grooves). Monthly samples were collected: water samples close to the reef lagoon drain channels and at bottom depth at each station, and sediment traps were recovered and replaced also at each station. Reef Benthos videotransects were recorded bi-monthly at each station to assess its condition. Macroalgae and filamentous algae dominate benthic cover (up to 50%), hard-coral cover ranges from 5-9%. Five coral-diseases were recorded, affecting 10.16% of the coral colonies: Caribbean Ciliate Infection, White Band, Purple Spots, White Spots and Yellow Band. The sedimentation rate -sr- ranged from 0.13 to 83.7 mg/cm2/day during the year; 86% of the samples had a sr ≤ 10 mg/cm2/day (reefs not stressed); 13% of the samples had a sr ranging from 10 to 50 mg/cm2/day (stressed reefs); and 1% of the samples were over the critical threshold (>50 mg/cm2/day). Dissolved Inorganic Nitrogen concentrations during the year were above those recorded previously in Caribbean reefs. The most abundant fraction was ammonium, surpassing both Mexican norms: For protection of aquatic life in coastal zones (0.01 mg/L), and the critical threshold for aquatic life (0.4 mg/L). These concentration limits are considered as drivers of eutrophication, one of the main established causes of reef degradation globally. High concentrations of ammonium and other nutrients have been linked to increases in algae cover and coral diseases incidence, and to decreases in rates of coral calcification, fertility, production and viability of coral larvae, and the associated diversity loss.

State-of-the art of dc components for secondary power distribution of Space Station Freedom

NASA Technical Reports Server (NTRS)

Krauthamer, Stanley; Gangal, Mukund; Das, Radhe S. L.

1991-01-01

120-V dc secondary power distribution has been selected for Space Station Freedom. State-of-the art components and subsystems are examined in terms of performance, size, and topology. One of the objectives of this work is to inform Space Station users what is available in power supplies and power control devices. The other objective is to stimulate interest in the component industry so that more focused product development can be started. Based on results of this study, it is estimated that, with some redesign, modifications, and space qualification, may of these components may be applied to Space Station needs.

Contrasting patterns of phytoplankton pigments and chemotaxonomic groups along 30°S in the subtropical South Atlantic Ocean

NASA Astrophysics Data System (ADS)

Araujo, Milton Luiz Vieira; Mendes, Carlos Rafael Borges; Tavano, Virginia Maria; Garcia, Carlos Alberto Eiras; Baringer, Molly O'Neil

2017-02-01

This work describes the spatial distribution of pigments and main taxonomic groups of phytoplankton in the biogeochemical provinces of the subtropical South Atlantic Ocean, along 30°S latitude. Seawater samples (surface to 200 m depth) were collected along 120 oceanographic stations occupied in the early austral spring of 2011, during a CLIVAR Repeat Hydrography cruise. The pigments were identified and quantified by high performance liquid chromatography (HPLC), and CHEMTAX software was used to determine the relative contributions of the main taxonomic groups to total chlorophyll a (phytoplankton biomass index). Sampling stations were grouped into three provinces: Africa, Gyre, and Brazil, corresponding to the eastern, central, and western sectors of the transect, respectively. Our results showed that both vertical and horizontal distribution patterns of pigments and taxonomic groups were mainly determined by the availability of light and/or nutrients. Photosynthetic carotenoids (PSCs), associated with small flagellates (mainly haptophytes), dominated the light-limited and nutrient-enhanced deep chlorophyll maximum (DCM) layers of both the Brazil and Gyre provinces, as well as the upwelling influenced surface waters of the Africa province. The latter showed the highest chlorophyll a values ​​(>1 mg m-3) and abundance of dinoflagellates in the coastal region. Photoprotective carotenoids (PPCs) were predominant in the nutrient-poor and well-lit surface layers of the Brazil and Gyre provinces, associated with a low content of chlorophyll a ( 0.1 mg m-3) and dominance of prokaryotes (Synechoccocus and Prochloroccocus). This study demonstrates that pigment analysis can provide a useful approach to better understand the distribution of phytoplankton communities along physical-chemical gradients in a still undersampled region of the South Atlantic Ocean.

Heterogeneous distribution in sediments and dispersal in waters of Alexandrium minutum in a semi-enclosed coastal ecosystem.

PubMed

Klouch, Z K; Caradec, F; Plus, M; Hernández-Fariñas, T; Pineau-Guillou, L; Chapelle, A; Schmitt, S; Quéré, J; Guillou, L; Siano, R

2016-12-01

Within the framework of research aimed at using genetic methods to evaluate harmful species distribution and their impact on coastal ecosystems, a portion of the ITS1rDNA of Alexandrium minutum was amplified by real-time PCR from DNA extracts of superficial (1-3cm) sediments of 30 subtidal and intertidal stations of the Bay of Brest (Brittany, France), during the winters of 2013 and 2015. Cell germinations and rDNA amplifications of A. minutum were obtained for sediments of all sampled stations, demonstrating that the whole bay is currently contaminated by this toxic species. Coherent estimations of ITS1rDNA copy numbers were obtained for the two sampling cruises, supporting the hypothesis of regular accumulation of A. minutum resting stages in the south-eastern, more confined embayments of the study area, where fine-muddy sediments are also more abundant. Higher ITS1rDNA copy numbers were detected in sediments of areas where blooms have been seasonally detected since 2012. This result suggests that specific genetic material estimations in superficial sediments of the bay may be a proxy of the cyst banks of A. minutum. The simulation of particle trajectory analyses by a Lagrangian physical model showed that blooms occurring in the south-eastern part of the bay are disconnected from those of the north-eastern zone. The heterogeneous distribution of A. minutum inferred from both water and sediment suggests the existence of potential barriers for the dispersal of this species in the Bay of Brest and encourages finer analyses at the population level for this species within semi-enclosed coastal ecosystems. Copyright © 2016 Elsevier B.V. All rights reserved.

Temporal variability of the bioaerosol background at a subway station: concentration level, size distribution, and diversity of airborne bacteria.

PubMed

Dybwad, Marius; Skogan, Gunnar; Blatny, Janet Martha

2014-01-01

Naturally occurring bioaerosol environments may present a challenge to biological detection-identification-monitoring (BIODIM) systems aiming at rapid and reliable warning of bioterrorism incidents. One way to improve the operational performance of BIODIM systems is to increase our understanding of relevant bioaerosol backgrounds. Subway stations are enclosed public environments which may be regarded as potential bioterrorism targets. This study provides novel information concerning the temporal variability of the concentration level, size distribution, and diversity of airborne bacteria in a Norwegian subway station. Three different air samplers were used during a 72-h sampling campaign in February 2011. The results suggested that the airborne bacterial environment was stable between days and seasons, while the intraday variability was found to be substantial, although often following a consistent diurnal pattern. The bacterial levels ranged from not detected to 10(3) CFU m(-3) and generally showed increased levels during the daytime compared to the nighttime levels, as well as during rush hours compared to non-rush hours. The airborne bacterial levels showed rapid temporal variation (up to 270-fold) on some occasions, both consistent and inconsistent with the diurnal profile. Airborne bacterium-containing particles were distributed between different sizes for particles of >1.1 μm, although ∼50% were between 1.1 and 3.3 μm. Anthropogenic activities (mainly passengers) were demonstrated as major sources of airborne bacteria and predominantly contributed 1.1- to 3.3-μm bacterium-containing particles. Our findings contribute to the development of realistic testing and evaluation schemes for BIODIM equipment by providing information that may be used to simulate operational bioaerosol backgrounds during controlled aerosol chamber-based challenge tests with biological threat agents.

Temporal Variability of the Bioaerosol Background at a Subway Station: Concentration Level, Size Distribution, and Diversity of Airborne Bacteria

PubMed Central

Dybwad, Marius; Skogan, Gunnar

2014-01-01

Naturally occurring bioaerosol environments may present a challenge to biological detection-identification-monitoring (BIODIM) systems aiming at rapid and reliable warning of bioterrorism incidents. One way to improve the operational performance of BIODIM systems is to increase our understanding of relevant bioaerosol backgrounds. Subway stations are enclosed public environments which may be regarded as potential bioterrorism targets. This study provides novel information concerning the temporal variability of the concentration level, size distribution, and diversity of airborne bacteria in a Norwegian subway station. Three different air samplers were used during a 72-h sampling campaign in February 2011. The results suggested that the airborne bacterial environment was stable between days and seasons, while the intraday variability was found to be substantial, although often following a consistent diurnal pattern. The bacterial levels ranged from not detected to 103 CFU m−3 and generally showed increased levels during the daytime compared to the nighttime levels, as well as during rush hours compared to non-rush hours. The airborne bacterial levels showed rapid temporal variation (up to 270-fold) on some occasions, both consistent and inconsistent with the diurnal profile. Airborne bacterium-containing particles were distributed between different sizes for particles of >1.1 μm, although ∼50% were between 1.1 and 3.3 μm. Anthropogenic activities (mainly passengers) were demonstrated as major sources of airborne bacteria and predominantly contributed 1.1- to 3.3-μm bacterium-containing particles. Our findings contribute to the development of realistic testing and evaluation schemes for BIODIM equipment by providing information that may be used to simulate operational bioaerosol backgrounds during controlled aerosol chamber-based challenge tests with biological threat agents. PMID:24162566

Observation of high energy radiation in the Surface Detectors of the Pierre Auger Observatory in correspondance with lightning strikes.

NASA Astrophysics Data System (ADS)

Colalillo, R.; Mussa, R.

2017-12-01

Very peculiar events have been detected with the surface detector (SD) of the Pierre Auger Observatory. These events are characterized by stations collecting a long-lasting signal compared to cosmic-ray signal, and by stations where the high-frequency noise was observed. This noise could be associated with a lightning-caused signal. A correlation between our events and lightning strikes as recorded by the WWLLN (World Wide Lightning Location Network) network was found. The time difference between lightning and Auger data spans from 10 μs to 100 ms. The long-lasting signals are observed in stations distributed in a circular pattern with a typical radius of about 6 km for the big events, that are almost the whole sample. The amplitude of the signal is bigger close to the centre of the circle and decreases while the distance from the centre increases. The energy deposited in each station spans from 10 GeV to 1 TeV, well above the typical energies deposited by cosmic rays showers. The first stations reached by the signal are the central ones. The observed timing is consistent with a spherical or cylindrical front propagating from a source very close to the ground. The main characteristics of these events will be described. Studies are under way to understand phenomena and mechanisms that may have generated them.

Global distribution of ozone for various seasons

NASA Technical Reports Server (NTRS)

Koprova, L. I.

1979-01-01

A technique which was used to obtain a catalog of the seasonal global distribution of ozone is presented. The technique is based on the simultaneous use of 1964-1975 data on the total ozone content from a worldwide network of ozonometric stations and on the vertical ozone profile from ozone sounding stations.

Considerations on the effects of tidal regimes in the movement of floating litter in an estuarine environment: Case study of the estuarine system of Santos-São Vicente, Brazil.

PubMed

Fernandino, Gerson; Elliff, Carla Isobel; Frutuoso, Gabriela Amado; Silva, Eric Vinícius Nascimento Malaquias da; Gama, Guilherme Santiago; Sousa, João Henrique de Oliveira; Silva, Iracema Reimão

2016-09-15

Floating litter in the estuarine system of Santos-São Vicente is common and is part of day-to-day activities of various users of the area. The objective of the present study was to carry out a quali-quantitative evaluation of the occurrence of floating litter, to infer their sources, and to identify environmental factors that are likely to control occurrence and distribution, with particular emphasis on the effects of tidal regimes. Six sampling stations were selected along the aforementioned estuary and visited monthly between July 2010 and January 2012. Floating litter was counted from a fixed sampling station. Plastics prevailed (89.64%) and their main source was domestic activities (55.41%). More litter was found during ebb spring tides, with higher concentrations obeying confluence patterns of the estuary's channels. Results indicated that occurrence can be attributed to the deficiency in basic sewage system in the area and the deliberate disposal into the estuary by the local population. Copyright © 2016 Elsevier Ltd. All rights reserved.

International Space Station Major Constituent Analyzer On-Orbit Performance

NASA Technical Reports Server (NTRS)

Gardner, Ben D.; Erwin, Philip M.; Thoresen, Souzan; Granahan, John; Matty, Chris

2011-01-01

The Major Constituent Analyzer (MCA) is an integral part of the International Space Station (ISS) Environmental Control and Life Support System (ECLSS). The MCA is a mass spectrometer-based instrument designed to provide critical monitoring of six major atmospheric constituents; nitrogen, oxygen, hydrogen, carbon dioxide, methane, and water vapor. These gases are sampled continuously and automatically in all United States On-Orbit Segment (USOS) modules via the Sample Distribution System (SDS). The MCA is the primary tool for management of atmosphere constituents and is therefore critical for ensuring a habitable ISS environment during both nominal ISS operations and campout EVA preparation in the Airlock. The MCA has been in operation in the US Destiny Laboratory Module for over 10 years, and a second MCA has been delivered to the ISS for Node 3 operation. This paper discusses the performance of the MCA over the two past year, with particular attention to lessons learned regarding the operational life of critical components. Recent data have helped drive design upgrades for a new set of orbit-replaceable units (ORUs) currently in production. Several ORU upgrades are expected to increase expected lifetimes and reliability.

Assessment of heavy metals in sediment of Aguamilpa Dam, Mexico.

PubMed

Rangel-Peraza, Jesús Gabriel; de Anda, José; González-Farías, Fernando A; Rode, Michael; Sanhouse-García, Antonio; Bustos-Terrones, Yaneth A

2015-03-01

The Aguamilpa Dam is part of the reservoir cascade system formed by four reservoirs in the middle and lower part of the Santiago River. For decades, this system has received urban and industrial wastewater from the metropolitan area of Guadalajara and the runoff of agricultural fields located in the river basin. The present study was carried out to obtain a preliminary assessment on the concentration distribution of heavy metals (Al, Ba, Cd, Cr, Cu, Fe, Hg, Mg, Ni, Pb, and Zn) in surface sediments of the Aguamilpa reservoir collected from 10 sampling stations. The metal concentrations (mg kg(-1)) in the sampling stations ranged as follows: Al, 27,600-7760; Ba, 190.0-15.9; Cd, 0.27-0.02; Cr, 18.30-0.22; Cu, 60.80-0.79; Fe, 15,900-4740; Hg, 0.04-0.01; Mg, 7590-8.05; Ni, 189.00-0.24; Pb, 13.6-1.64; and Zn, 51.8-14.8. Significant spatial variation in concentrations was observed for Al, Fe, and Pb. Sediment pollution was evaluated using the enrichment factor, the geo-accumulation index, the pollution load index, and sediment quality guidelines. Based on geo-accumulation and pollution load indexes, Aguamilpa sediments were found, in some sampling stations, as unpolluted to moderately polluted with Ni, Cd, Cu, and Mg. Enrichment factors showed that Cd is highly related to agricultural activities that take place in the surrounding areas of the Aguamilpa reservoir. Despite these results, none of the heavy metals evaluated exceeded international concentrations limits, indicating that the Aguamilpa reservoir surface sediments are not contaminated.

Exercise of the SSM/PMAD Breadboard. [Space Station Module/Power Management And Distribution

NASA Technical Reports Server (NTRS)

Walls, Bryan

1989-01-01

The Space Station Module Power Management and Distribution (SSM/PMAD) Breadboard is a test facility designed for advanced development of space power automation. Originally designed for 20-kHz power, the system is being converted to work with direct current (dc). Power levels are on a par with those expected for a Space Station module. Some of the strengths and weaknesses of the SSM/PMAD system in design and function are examined, and the future directions foreseen for the system are outlined.

Station for spatially distributed measurements of soil moisture and ambient temperature

NASA Astrophysics Data System (ADS)

Jankovec, Jakub; Šanda, Martin; Haase, Tomáš; Sněhota, Michal; Wild, Jan

2013-04-01

Third generation of combined thermal and soil moisture standalone field station coded TMS3 with wireless communication is presented. The device combines three thermometers (MAXIM/DALLAS Semiconductor DS7505U with -55 to +125°C range and 0.0625°C resolution, 0.5°C precision in 0 to +70°C range and 2°C precision out of this range). Soil moisture measurement is performed based on time domain transmission (TDT) principle for the full range of soil moisture with 0.025% resolution within the full possible soil moisture span for the most typical conditions of dry to saturated soils with safe margins to enable measurements in freezing, hot or saline soils. Principal compact version is designed for temperature measurements approximately at heights -10, 0 and +15 cm relative to soil surface when installed vertically and soil moisture measurements between 0 and 12 cm below surface. Set of buriable/subsurface stations each with 2.2 meter extension cord with soil and surface temperature measurement provides possibility to scan vertical soil profile for soil moisture and temperature at desired depths. USB equipped station is designed for streamed direct data acquisition in laboratory use in 1s interval. Station is also equipped with the shock sensor indicating the manipulation. Presented version incorporates life time permanent data storage (0.5 million logs). Current sensor design aims towards improved durability in harsh outdoor environment with reliable functioning in wet conditions withstanding mechanical or electric shock destruction. Insertion into the soil is possible by pressing with the use of a simple plastic cover. Data are retrieved by contact portable pocket collector (second generation) or by RFID wireless communication for hundreds meter distance (third generation) in either star pattern of GSM hub to stations or lined up GSM to station to another station both in comprised data packets. This option will allow online data harvesting and real time process control (e.g. optimized irrigation) by the end of 2013. User selected regimes of scanning in the field standalone model is 1,5 or 15 minutes for soil moisture and 1, 5, 10 or 15 minutes for the temperature (in their practical combinations) with a battery and datastorage lifetime ranging 1 - 10 years. Basic station diagnostics is recorded daily, comprehensive check is performed monthly. The TMS2 undergoes calibration on sets of soils. Disturbed and packed cylindrical soil samples (approx. 20 liter) were subject to forced bottom air ventilation to distribute the moisture evenly along vertical axis during drying the sample with increased intensity. Database of soil-specific calibration curves is being built for various soil samples. TMS2 station has been calibrated for soil materials: sandy loam, quartz sand and peat. Calibration on selected undisturbed 7 liter samples, previously CT scanned for correct sensor placement, is in the progress. Temperature and salinity influence on the soil moisture results in drift of 0.05%/°C and 7%/(in full range of 0 to 10 miliSiemens/cm) and additional 2%/(in the range of 10 to 20 miliSiemens/cm) as found in 100% moisture solution. Extended testing of TMS1 generation, predecessor of current design, is successfully performed in variety of field locations (central Europe, central Africa, Himalaya region). Results of long-term measurement at hundreds of localities are successfully used for i) evaluation of species-specific environmental requirements (for different species of plants, bryophytes and fungi) and ii) extrapolation of microclimatic conditions over large areas of rugged sandstone relief with assistance of accurate, LiDAR based, digital terrain model. TMS1 units are e.g. also applied for continuous measurement of temperature and moisture of coarse woody debris, which serves as an important substrate for establishment and growth of seedlings and is thus crucial for natural regeneration of many forest ecosystems. The research is supported by the Technology Agency of the Czech Republic projects No. TA01021283 and SGS12/130/OHK1/2T/11.

Distribution of Arctic and Pacific copepods and their habitat in the northern Bering and Chukchi seas

NASA Astrophysics Data System (ADS)

Sasaki, Hiroko; Matsuno, Kohei; Fujiwara, Amane; Onuka, Misaki; Yamaguchi, Atsushi; Ueno, Hiromichi; Watanuki, Yutaka; Kikuchi, Takashi

2016-08-01

The advection of warm Pacific water and the reduction in sea ice in the western Arctic Ocean may influence the abundance and distribution of copepods, a key component of food webs. To quantify the factors affecting the abundance of copepods in the northern Bering and Chukchi seas, we constructed habitat models explaining the spatial patterns of large and small Arctic and Pacific copepods separately. Copepods were sampled using NORPAC (North Pacific Standard) nets. The structures of water masses indexed by principle component analysis scores, satellite-derived timing of sea ice retreat, bottom depth and chlorophyll a concentration were integrated into generalized additive models as explanatory variables. The adequate models for all copepods exhibited clear continuous relationships between the abundance of copepods and the indexed water masses. Large Arctic copepods were abundant at stations where the bottom layer was saline; however they were scarce at stations where warm fresh water formed the upper layer. Small Arctic copepods were abundant at stations where the upper layer was warm and saline and the bottom layer was cold and highly saline. In contrast, Pacific copepods were abundant at stations where the Pacific-origin water mass was predominant (i.e. a warm, saline upper layer and saline and a highly saline bottom layer). All copepod groups showed a positive relationship with early sea ice retreat. Early sea ice retreat has been reported to initiate spring blooms in open water, allowing copepods to utilize more food while maintaining their high activity in warm water without sea ice and cold water. This finding indicates that early sea ice retreat has positive effects on the abundance of all copepod groups in the northern Bering and Chukchi seas, suggesting a change from a pelagic-benthic-type ecosystem to a pelagic-pelagic type.

International Space Station (ISS) Bacterial Filter Elements (BFEs): Filter Efficiency and Pressure Drop Testing of Returned Units

NASA Technical Reports Server (NTRS)

Green, Robert D.; Agui, Juan H.; Vijayakumar, R.; Berger, Gordon M.; Perry, Jay L.

2017-01-01

The air quality control equipment aboard the International Space Station (ISS) and future deep space exploration vehicles provide the vital function of maintaining a clean cabin environment for the crew and the hardware. This becomes a serious challenge in pressurized space compartments since no outside air ventilation is possible, and a larger particulate load is imposed on the filtration system due to lack of sedimentation. The ISS Environmental Control and Life Support (ECLS) system architecture in the U.S. Segment uses a distributed particulate filtration approach consisting of traditional High-Efficiency Particulate Air (HEPA) filters deployed at multiple locations in each U.S. Seg-ment module; these filters are referred to as Bacterial Filter Elements, or BFEs. In our previous work, we presented results of efficiency and pressure drop measurements for a sample set of two returned BFEs with a service life of 2.5 years. In this follow-on work, we present similar efficiency, pressure drop, and leak tests results for a larger sample set of six returned BFEs. The results of this work can aid the ISS Program in managing BFE logistics inventory through the stations planned lifetime as well as provide insight for managing filter element logistics for future exploration missions. These results also can provide meaningful guidance for particulate filter designs under consideration for future deep space exploration missions.

Simple Random Sampling-Based Probe Station Selection for Fault Detection in Wireless Sensor Networks

PubMed Central

Huang, Rimao; Qiu, Xuesong; Rui, Lanlan

2011-01-01

Fault detection for wireless sensor networks (WSNs) has been studied intensively in recent years. Most existing works statically choose the manager nodes as probe stations and probe the network at a fixed frequency. This straightforward solution leads however to several deficiencies. Firstly, by only assigning the fault detection task to the manager node the whole network is out of balance, and this quickly overloads the already heavily burdened manager node, which in turn ultimately shortens the lifetime of the whole network. Secondly, probing with a fixed frequency often generates too much useless network traffic, which results in a waste of the limited network energy. Thirdly, the traditional algorithm for choosing a probing node is too complicated to be used in energy-critical wireless sensor networks. In this paper, we study the distribution characters of the fault nodes in wireless sensor networks, validate the Pareto principle that a small number of clusters contain most of the faults. We then present a Simple Random Sampling-based algorithm to dynamic choose sensor nodes as probe stations. A dynamic adjusting rule for probing frequency is also proposed to reduce the number of useless probing packets. The simulation experiments demonstrate that the algorithm and adjusting rule we present can effectively prolong the lifetime of a wireless sensor network without decreasing the fault detected rate. PMID:22163789

Simple random sampling-based probe station selection for fault detection in wireless sensor networks.

PubMed

Huang, Rimao; Qiu, Xuesong; Rui, Lanlan

2011-01-01

Fault detection for wireless sensor networks (WSNs) has been studied intensively in recent years. Most existing works statically choose the manager nodes as probe stations and probe the network at a fixed frequency. This straightforward solution leads however to several deficiencies. Firstly, by only assigning the fault detection task to the manager node the whole network is out of balance, and this quickly overloads the already heavily burdened manager node, which in turn ultimately shortens the lifetime of the whole network. Secondly, probing with a fixed frequency often generates too much useless network traffic, which results in a waste of the limited network energy. Thirdly, the traditional algorithm for choosing a probing node is too complicated to be used in energy-critical wireless sensor networks. In this paper, we study the distribution characters of the fault nodes in wireless sensor networks, validate the Pareto principle that a small number of clusters contain most of the faults. We then present a Simple Random Sampling-based algorithm to dynamic choose sensor nodes as probe stations. A dynamic adjusting rule for probing frequency is also proposed to reduce the number of useless probing packets. The simulation experiments demonstrate that the algorithm and adjusting rule we present can effectively prolong the lifetime of a wireless sensor network without decreasing the fault detected rate.

NASA Global GNSS Network (GGN) Status and Plans

NASA Astrophysics Data System (ADS)

Doelger, S.; Sklar, J.; Blume, F.; Meertens, C. M.; Mattioli, G. S.

2015-12-01

UNAVCO, in conjunction with JPL, is responsible for monitoring the 62 GNSS permanent stations, which include 88 GPS receivers, which comprise the NASA Global GNSS Network (GGN). These sites represent approximately 16% of the ~400 International GNSS Service (IGS) stations, and they provide a globally distributed GNSS network to support NASA operations and its commitments to GGOS. UNAVCO provides data flow monitoring, trouble-shooting, station installation, maintenance, as well as engineering services to improve the capabilities and performance of station infrastructure. Activities this past year include the installation of a geodetic quality wellhead monument for the new SEY2 station to replace SEY1, which is mounted on a UCSD seismic station in the Seychelles Islands. SEY1 will be removed soon to accommodate planned maintenance and upgrades by UCSD. Data from both SEY1 and SEY2 are being collected concurrently until maintenance begins. MRTG (Multi Router Traffic Grapher), a tool to aid in characterizing bandwidth usage and to identify communications problems, is now being used to monitor data throughput at 7 stations where VSAT or radio telemetry are used, including: ABPO; AREQ; FALK; GUAM; HARV; ISPA; QUIN; and STHL. Aging computers are being replaced with new hardware running Linux CentOS. These are semi-ruggedized low power solid-state systems built to endure challenging environments. With the aid of on-site collaborators, systems are now deployed at: FALK; CUSV; KELY; STHL; SANT; and ZAMB. Last, 4 new GPS stations were deployed for NASA's Space Geodesy Project (SGP); three of which (KOKF, KOKG, and KOKR) are located at Koke'e Park Geophysical Observatory on Kauai, Hawai'i, and HAL1 at the Haleakala observatory complex on Maui, Hawai'i. A campaign system was set up at Koke'e in order to sample data quality to determine if an additional station would be viable. Planning is ongoing for deployment of several new stations next year at McDonald Observatory (TX).

Charging Guidance of Electric Taxis Based on Adaptive Particle Swarm Optimization

PubMed Central

Niu, Liyong; Zhang, Di

2015-01-01

Electric taxis are playing an important role in the application of electric vehicles. The actual operational data of electric taxis in Shenzhen, China, is analyzed, and, in allusion to the unbalanced time availability of the charging station equipment, the electric taxis charging guidance system is proposed basing on the charging station information and vehicle information. An electric taxis charging guidance model is established and guides the charging based on the positions of taxis and charging stations with adaptive mutation particle swarm optimization. The simulation is based on the actual data of Shenzhen charging stations, and the results show that electric taxis can be evenly distributed to the appropriate charging stations according to the charging pile numbers in charging stations after the charging guidance. The even distribution among the charging stations in the area will be achieved and the utilization of charging equipment will be improved, so the proposed charging guidance method is verified to be feasible. The improved utilization of charging equipment can save public charging infrastructure resources greatly. PMID:26236770

Charging Guidance of Electric Taxis Based on Adaptive Particle Swarm Optimization.

PubMed

Niu, Liyong; Zhang, Di

2015-01-01

Electric taxis are playing an important role in the application of electric vehicles. The actual operational data of electric taxis in Shenzhen, China, is analyzed, and, in allusion to the unbalanced time availability of the charging station equipment, the electric taxis charging guidance system is proposed basing on the charging station information and vehicle information. An electric taxis charging guidance model is established and guides the charging based on the positions of taxis and charging stations with adaptive mutation particle swarm optimization. The simulation is based on the actual data of Shenzhen charging stations, and the results show that electric taxis can be evenly distributed to the appropriate charging stations according to the charging pile numbers in charging stations after the charging guidance. The even distribution among the charging stations in the area will be achieved and the utilization of charging equipment will be improved, so the proposed charging guidance method is verified to be feasible. The improved utilization of charging equipment can save public charging infrastructure resources greatly.

Sediment transport dynamics at the Ria de Vigo inferred from two mooring stations

NASA Astrophysics Data System (ADS)

Campistegui, Aimar; Bernabeu, Ana; Rey, Daniel

2010-05-01

The aim of this study is to characterise bottom currents and associated seafloor sediments at the Ría de Vigo, a 28 km long by 12 km wide funnel shaped coastal embayments at the NW coast of the Iberian Peninsula. The embayment is south-westerly oriented, against the general northerly trend of the main coast, and partially closed at its mouth by the Cies Islands. Forms a wide U-valley with central depths varying from 10 to 60 m. Hydrodynamics shows a semidiurnal mesotidal regime, negative estuarine circulation; and important south-western wave climate component, particularly in winter. Coarse sediments are mostly siliciclastic-bioclastic carbonates mixtures and are preferentially distributed at shallow depths parallel to the coast. Fine grained sediments mostly consist of mud and are preferentially distributed in the most internal parts and occupying the deep central parts of the embayment. The survey was carried mooring two stations at the inner and outer parts of the embayment, the later quite close to the southern mouth. In each station the current velocity and direction, salinity, temperature, turbidity, pressure and dissolved oxygen were measured near the bottom. The survey period covered two weeks, from June 28th till July 11th of 2005. Surficial sediment grain size was characterised in representative sediment samples from different points of the ría, including the stations sites, using box corers. The analyzed temperature and salinity data show an upwelling process, taking place since the third day on, registering low temperature values, about 13°C and high salinity values, about 36.5 ppt. During the non-upwelling period the bottom current direction in both stations was different, NE during the flood SW during the ebb, at the station 1 and eastwards during the flood and SW during the ebb at the station 2. But during the upwelling period was the same at both stations, NE-SW. At the same time the velocity during whole survey period was higher in the first station than in the second station. The grain size at the second outermost station was coarse sand and mostly muds in the innermost. The results indicate that there are one or more factors affecting the current direction at the bottom at the station 2 which make it change during the non-upwelling period but not during the upwelling period. This implies a different transport direction of the fine sediment for each period. The calculated shear stress at this station indicates no transport by tidal currents, and subsequently that the main transport mechanism is dominated by waves in the area. This work was supported by projects PGIDIT06TAM31201PR of the Xunta de Galicia and TOPOSEDPROX and PROMARES and MICINN of the Spanish Goverment and ANCORIM, BIOREM and OILDEBEACH of the EU

Aerodynamic heating rate distributions induced by trailing edge controls on hypersonic aircraft configurations at Mach 8

NASA Technical Reports Server (NTRS)

Kaufman, L. G., II; Johnson, C. B.

1984-01-01

Aerodynamic surface heating rate distributions in three dimensional shock wave boundary layer interaction flow regions are presented for a generic set of model configurations representative of the aft portion of hypersonic aircraft. Heat transfer data were obtained using the phase change coating technique (paint) and, at particular spanwise and streamwise stations for sample cases, by the thin wall transient temperature technique (thermocouples). Surface oil flow patterns are also shown. The good accuracy of the detailed heat transfer data, as attested in part by their repeatability, is attributable partially to the comparatively high temperature potential of the NASA-Langley Mach 8 Variable Density Tunnel. The data are well suited to help guide heating analyses of Mach 8 aircraft, and should be considered in formulating improvements to empiric analytic methods for calculating heat transfer rate coefficient distributions.

Trans-Atlantic variability in ecology of the pelagic tunicate Salpa thompsoni near the Antarctic Polar Front

NASA Astrophysics Data System (ADS)

Pakhomov, Evgeny A.; Hunt, Brian P. V.

2017-04-01

The distribution, density, demography and feeding dynamics of the pelagic tunicate Salpa thompsoni were investigated during the trans-Atlantic ANTARKTIS XXVIII/3 expedition to the Southern Ocean, on board RV Polarstern, between January and March 2012. Net samples were collected using an RMT-8 at four major sampling regions in the proximity of the Antarctic Polar Front (APF): along a 10°E transect, Salpastan, 12°W eulerian study, and the South Georgia Basin. Salps, mostly S. thompsoni, were found at all but one station and with few exceptions contributed <<40% to total zooplankton in terms of both abundance and biomass. Salp abundance and biomass was lowest (6.2 ind.1000 m-3 and 0.8 mgDW m-3) north of the APF along the 10°E transect and highest (3150 ind.1000 m-3 and 20.5 mgDW m-3) at the Salpastan station south of the APF. Size distributions of S. thompsoni aggregates and solitaries, and their developmental dynamics, were similar in all locations except the Salpastan region. In aggregates, the overall salp size distributions were strongly right-tailed with the mass of the distribution always concentrated in the left where small aggregates (6-10 mm) dominated. During the eulerian study at 12°W, several cohorts of aggregates and solitaries were traceable allowing assessment of the daily growth rates of S. thompsoni. Estimated in situ growth rates of aggregates and solitaries were 0.53±0.18 and 2.83±0.42 mm day-1, respectively, and the complete S. thompsoni life cycle duration (sexual+asexual) during austral summer at the APF region may have been as short as 2-3 months. The rapid growth rates of S. thompsoni found in this study urgently require further research to re-evaluate salp life cycle in the Southern Ocean.

Designing optimized multi-species monitoring networks to detect range shifts driven by climate change: a case study with bats in the North of Portugal.

PubMed

Amorim, Francisco; Carvalho, Sílvia B; Honrado, João; Rebelo, Hugo

2014-01-01

Here we develop a framework to design multi-species monitoring networks using species distribution models and conservation planning tools to optimize the location of monitoring stations to detect potential range shifts driven by climate change. For this study, we focused on seven bat species in Northern Portugal (Western Europe). Maximum entropy modelling was used to predict the likely occurrence of those species under present and future climatic conditions. By comparing present and future predicted distributions, we identified areas where each species is likely to gain, lose or maintain suitable climatic space. We then used a decision support tool (the Marxan software) to design three optimized monitoring networks considering: a) changes in species likely occurrence, b) species conservation status, and c) level of volunteer commitment. For present climatic conditions, species distribution models revealed that areas suitable for most species occur in the north-eastern part of the region. However, areas predicted to become climatically suitable in the future shifted towards west. The three simulated monitoring networks, adaptable for an unpredictable volunteer commitment, included 28, 54 and 110 sampling locations respectively, distributed across the study area and covering the potential full range of conditions where species range shifts may occur. Our results show that our framework outperforms the traditional approach that only considers current species ranges, in allocating monitoring stations distributed across different categories of predicted shifts in species distributions. This study presents a straightforward framework to design monitoring schemes aimed specifically at testing hypotheses about where and when species ranges may shift with climatic changes, while also ensuring surveillance of general population trends.

Distribution of sea snakes in the Great Barrier Reef Marine Park: observations from 10 yrs of baited remote underwater video station (BRUVS) sampling

NASA Astrophysics Data System (ADS)

Udyawer, Vinay; Cappo, Mike; Simpfendorfer, Colin A.; Heupel, Michelle R.; Lukoschek, Vimoksalehi

2014-09-01

The distributions of three species of sea snake (olive sea snake: Aipysurus laevis, spine-bellied sea snake: Lapemis curtus, and ornate sea snake: Hydrophis ocellatus) were estimated over 14° of latitude within the Great Barrier Reef Marine Park (GBRMP) using data from baited remote underwater video stations (BRUVS). A total of 2,471 deployments of BRUVS were made in a range of locations, in sites open and closed to trawl fishing. Sightings of sea snakes were analysed alongside six spatial factors [depth, relative distance across (longitude) and along (latitude) the GBRMP, proximity to land, proximity to the nearest reef, and habitat complexity] to determine the factors that most strongly influenced the distribution and abundance of sea snakes. The results showed a strong latitudinal effect on the distribution of all three sea snake species, with the highest densities and diversities occurring in central and southern GBRMP locations, while the northern Great Barrier Reef was relatively depauperate in terms of both occurrence and diversity. Shallow inshore areas were identified as key habitats for A. laevis and L. curtus, whereas deeper offshore habitats were most important for H. ocellatus. No significant difference was found in the mean number of snakes sighted per hour between sites open and closed to trawling. There was a high degree of congruence in the distribution of sea snakes estimated from the BRUVS data and results from previous trawl and underwater visual surveys, demonstrating the utility of BRUVS to estimate distribution and relative abundance in these species of sea snake at broad spatial scales in a non-extractive manner.

Assessing coastal wetland vulnerability to sea-level rise along the northern Gulf of Mexico coast: Gaps and opportunities for developing a coordinated regional sampling network

PubMed Central

Griffith, Kereen T.; Larriviere, Jack C.; Feher, Laura C.; Cahoon, Donald R.; Enwright, Nicholas M.; Oster, David A.; Tirpak, John M.; Woodrey, Mark S.; Collini, Renee C.; Baustian, Joseph J.; Breithaupt, Joshua L.; Cherry, Julia A.; Conrad, Jeremy R.; Cormier, Nicole; Coronado-Molina, Carlos A.; Donoghue, Joseph F.; Graham, Sean A.; Harper, Jennifer W.; Hester, Mark W.; Howard, Rebecca J.; Krauss, Ken W.; Kroes, Daniel E.; Lane, Robert R.; McKee, Karen L.; Mendelssohn, Irving A.; Middleton, Beth A.; Moon, Jena A.; Piazza, Sarai C.; Rankin, Nicole M.; Sklar, Fred H.; Steyer, Greg D.; Swanson, Kathleen M.; Swarzenski, Christopher M.; Vervaeke, William C.; Willis, Jonathan M.; Wilson, K. Van

2017-01-01

Coastal wetland responses to sea-level rise are greatly influenced by biogeomorphic processes that affect wetland surface elevation. Small changes in elevation relative to sea level can lead to comparatively large changes in ecosystem structure, function, and stability. The surface elevation table-marker horizon (SET-MH) approach is being used globally to quantify the relative contributions of processes affecting wetland elevation change. Historically, SET-MH measurements have been obtained at local scales to address site-specific research questions. However, in the face of accelerated sea-level rise, there is an increasing need for elevation change network data that can be incorporated into regional ecological models and vulnerability assessments. In particular, there is a need for long-term, high-temporal resolution data that are strategically distributed across ecologically-relevant abiotic gradients. Here, we quantify the distribution of SET-MH stations along the northern Gulf of Mexico coast (USA) across political boundaries (states), wetland habitats, and ecologically-relevant abiotic gradients (i.e., gradients in temperature, precipitation, elevation, and relative sea-level rise). Our analyses identify areas with high SET-MH station densities as well as areas with notable gaps. Salt marshes, intermediate elevations, and colder areas with high rainfall have a high number of stations, while salt flat ecosystems, certain elevation zones, the mangrove-marsh ecotone, and hypersaline coastal areas with low rainfall have fewer stations. Due to rapid rates of wetland loss and relative sea-level rise, the state of Louisiana has the most extensive SET-MH station network in the region, and we provide several recent examples where data from Louisiana’s network have been used to assess and compare wetland vulnerability to sea-level rise. Our findings represent the first attempt to examine spatial gaps in SET-MH coverage across abiotic gradients. Our analyses can be used to transform a broadly disseminated and unplanned collection of SET-MH stations into a coordinated and strategic regional network. This regional network would provide data for predicting and preparing for the responses of coastal wetlands to accelerated sea-level rise and other aspects of global change. PMID:28902904

Assessing coastal wetland vulnerability to sea-level rise along the northern Gulf of Mexico coast: Gaps and opportunities for developing a coordinated regional sampling network

USGS Publications Warehouse

Osland, Michael J.; Griffith, Kereen T.; Larriviere, Jack C.; Feher, Laura C.; Cahoon, Donald R.; Enwright, Nicholas M.; Oster, David A.; Tirpak, John M.; Woodrey, Mark S.; Collini, Renee C.; Baustian, Joseph J.; Breithaupt, Joshua L.; Cherry, Julia A; Conrad, Jeremy R.; Cormier, Nicole; Coronado-Molina, Carlos A.; Donoghue, Joseph F.; Graham, Sean A.; Harper, Jennifer W.; Hester, Mark W.; Howard, Rebecca J.; Krauss, Ken W.; Kroes, Daniel; Lane, Robert R.; Mckee, Karen L.; Mendelssohn, Irving A.; Middleton, Beth A.; Moon, Jena A.; Piazza, Sarai; Rankin, Nicole M.; Sklar, Fred H.; Steyer, Gregory D.; Swanson, Kathleen M.; Swarzenski, Christopher M.; Vervaeke, William; Willis, Jonathan M; Van Wilson, K.

2017-01-01

Coastal wetland responses to sea-level rise are greatly influenced by biogeomorphic processes that affect wetland surface elevation. Small changes in elevation relative to sea level can lead to comparatively large changes in ecosystem structure, function, and stability. The surface elevation table-marker horizon (SET-MH) approach is being used globally to quantify the relative contributions of processes affecting wetland elevation change. Historically, SET-MH measurements have been obtained at local scales to address site-specific research questions. However, in the face of accelerated sea-level rise, there is an increasing need for elevation change network data that can be incorporated into regional ecological models and vulnerability assessments. In particular, there is a need for long-term, high-temporal resolution data that are strategically distributed across ecologically-relevant abiotic gradients. Here, we quantify the distribution of SET-MH stations along the northern Gulf of Mexico coast (USA) across political boundaries (states), wetland habitats, and ecologically-relevant abiotic gradients (i.e., gradients in temperature, precipitation, elevation, and relative sea-level rise). Our analyses identify areas with high SET-MH station densities as well as areas with notable gaps. Salt marshes, intermediate elevations, and colder areas with high rainfall have a high number of stations, while salt flat ecosystems, certain elevation zones, the mangrove-marsh ecotone, and hypersaline coastal areas with low rainfall have fewer stations. Due to rapid rates of wetland loss and relative sea-level rise, the state of Louisiana has the most extensive SET-MH station network in the region, and we provide several recent examples where data from Louisiana’s network have been used to assess and compare wetland vulnerability to sea-level rise. Our findings represent the first attempt to examine spatial gaps in SET-MH coverage across abiotic gradients. Our analyses can be used to transform a broadly disseminated and unplanned collection of SET-MH stations into a coordinated and strategic regional network. This regional network would provide data for predicting and preparing for the responses of coastal wetlands to accelerated sea-level rise and other aspects of global change.

Assessing coastal wetland vulnerability to sea-level rise along the northern Gulf of Mexico coast: Gaps and opportunities for developing a coordinated regional sampling network.

PubMed

Osland, Michael J; Griffith, Kereen T; Larriviere, Jack C; Feher, Laura C; Cahoon, Donald R; Enwright, Nicholas M; Oster, David A; Tirpak, John M; Woodrey, Mark S; Collini, Renee C; Baustian, Joseph J; Breithaupt, Joshua L; Cherry, Julia A; Conrad, Jeremy R; Cormier, Nicole; Coronado-Molina, Carlos A; Donoghue, Joseph F; Graham, Sean A; Harper, Jennifer W; Hester, Mark W; Howard, Rebecca J; Krauss, Ken W; Kroes, Daniel E; Lane, Robert R; McKee, Karen L; Mendelssohn, Irving A; Middleton, Beth A; Moon, Jena A; Piazza, Sarai C; Rankin, Nicole M; Sklar, Fred H; Steyer, Greg D; Swanson, Kathleen M; Swarzenski, Christopher M; Vervaeke, William C; Willis, Jonathan M; Wilson, K Van

2017-01-01

Coastal wetland responses to sea-level rise are greatly influenced by biogeomorphic processes that affect wetland surface elevation. Small changes in elevation relative to sea level can lead to comparatively large changes in ecosystem structure, function, and stability. The surface elevation table-marker horizon (SET-MH) approach is being used globally to quantify the relative contributions of processes affecting wetland elevation change. Historically, SET-MH measurements have been obtained at local scales to address site-specific research questions. However, in the face of accelerated sea-level rise, there is an increasing need for elevation change network data that can be incorporated into regional ecological models and vulnerability assessments. In particular, there is a need for long-term, high-temporal resolution data that are strategically distributed across ecologically-relevant abiotic gradients. Here, we quantify the distribution of SET-MH stations along the northern Gulf of Mexico coast (USA) across political boundaries (states), wetland habitats, and ecologically-relevant abiotic gradients (i.e., gradients in temperature, precipitation, elevation, and relative sea-level rise). Our analyses identify areas with high SET-MH station densities as well as areas with notable gaps. Salt marshes, intermediate elevations, and colder areas with high rainfall have a high number of stations, while salt flat ecosystems, certain elevation zones, the mangrove-marsh ecotone, and hypersaline coastal areas with low rainfall have fewer stations. Due to rapid rates of wetland loss and relative sea-level rise, the state of Louisiana has the most extensive SET-MH station network in the region, and we provide several recent examples where data from Louisiana's network have been used to assess and compare wetland vulnerability to sea-level rise. Our findings represent the first attempt to examine spatial gaps in SET-MH coverage across abiotic gradients. Our analyses can be used to transform a broadly disseminated and unplanned collection of SET-MH stations into a coordinated and strategic regional network. This regional network would provide data for predicting and preparing for the responses of coastal wetlands to accelerated sea-level rise and other aspects of global change.

An application of sample entropy to precipitation in Paraíba State, Brazil

NASA Astrophysics Data System (ADS)

Xavier, Sílvio Fernando Alves; da Silva Jale, Jader; Stosic, Tatijana; dos Santos, Carlos Antonio Costa; Singh, Vijay P.

2018-05-01

A climate system is characterized to be a complex non-linear system. In order to describe the complex characteristics of precipitation series in Paraíba State, Brazil, we aim the use of sample entropy, a kind of entropy-based algorithm, to evaluate the complexity of precipitation series. Sixty-nine meteorological stations are distributed over four macroregions: Zona da Mata, Agreste, Borborema, and Sertão. The results of the analysis show that intricacies of monthly average precipitation have differences in the macroregions. Sample entropy is able to reflect the dynamic change of precipitation series providing a new way to investigate complexity of hydrological series. The complexity exhibits areal variation of local water resource systems which can influence the basis for utilizing and developing resources in dry areas.

The potential effect of global warming on the geographic and seasonal distribution of Phlebotomus papatasi in Southwest Asia

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cross, E.R.; Hyams, K.C.

1996-07-01

The distribution of Phlebotomus papatasi in Southwest Asia is thought to be highly dependent on temperature and relative humidity. A discriminant analysis model based on weather data and reported vector surveys was developed to predict the seasonal and geographic distribution of P. papatasi in this region. To simulate global warming, temperature values for 115 weather stations were increased by 1 {degrees}C, 3{degrees}C, and 5{degrees}C, and the outcome variable coded as unknown in the model. Probability of occurrence values were then predicted for each location with a weather station. Stations with positive probability of occurrence values for May, June, July, andmore » August were considered locations where two or more life cycles of P. papatasi could occur and which could support endemic transmission of leishmaniasis and sandfly fever. Among 115 weather stations, 71 (62%) would be considered endemic with current temperature conditions; 14 (12%) additional station could become endemic with an increase of 1 {degrees}C; 17 (15%) more than a 3{degrees}C increase; and 12 (10%) more (all but one station) with a t{degrees}C increase. In addition to increased geographic distribution, seasonality of disease transmission could be extended throughout 12 months of the year in 7 (6%) locations with at least a 3{degrees}C rise in temperature and in 29 (25%) locations with a 5{degrees}C rise. 15 refs., 4 figs.« less

Circadian rhythm of a red-tide dinoflagellate Peridinium quadridentatum in the port of Veracruz, Gulf of Mexico, its thecal morphology, nomenclature and geographical distribution.

PubMed

Okolodkov, Yuri B; Campos-Bautista, Guadalupe; Gárate-Lizárraga, Ismael

2016-07-15

A circadian rhythm of the dinoflagellate Peridinium quadridentatum was studied at a time-series station in the southwestern Gulf of Mexico, in May 2007. Different substrates (water column, the seagrass Thalassia testudinum, macroalgae, coral rubble and sandy sediment surface) were sampled at the site at 1.5-3.5m depth. In the samples of coral rubble, P. quadridentatum was scarce. In the water column, the species showed an abundance peak at 15:00. The cell abundance of P. quadridentatum in Thalassia samples increased from 15:00 until 18:00 (1.81×10(4)cells/gsubstratewet weight), and then continuously decreased until 06:00. Changes in P. quadridentatum cell abundance on macroalgae followed the same trend as on Thalassia, with the maximal value at 18:00. The higher abundance of P. quadridentatum (up to 1.40×10(4)cells/gSWW) in macroalgae samples showed the preference for seaweeds. P. quadridentatum has a neritic tropical-boreal distribution. A new combination is proposed: Peridinium quadridentatum var. trispiniferum. Copyright © 2016 Elsevier Ltd. All rights reserved.

Planktonic foraminifera as proxies of Upper Quaternary sedimentation in The Okhotsk sea

NASA Astrophysics Data System (ADS)

Romanova, Alexandra

2013-04-01

Analyzing planktonic foraminifera in marine sediments assists us in reconstructing historical maps of climatic changes. The object of the study is the Okhotsk Sea, largest Russian Far East sea. Okhotsk sea, like other marginal seas, is very sensitive to global and regional climate changes. Planktonic foraminifera are poorly investigated in Okhotsk sea. Studying of planktonic foraminifera in Okhotsk sea has some problems: low quantity of species, one taxon domination, low percents of another species, influence of dissolution. These facts don't allow us to use standard approaches for paleotemperature reconstructions using planktonic foraminifera. This research explores the response of this group of microorganisms to main paleoclimatic events in Okhotsk region and attempt to reveal the special characteristics of this proxy for interpreting the paleoodata. The research was based on samples from 4 cores in the central part of the sea and 67 sediment stations from north to south (total of about 270 samples). As a result of studying sediment stations we created a map of biogeographycal distribution of planktonic foraminifera and distinguished five provinces. Each province has specific quantitive and qualative characteristics of foraminifera assemblages that give us information about their modern distribution and ecological preferences. This information is necessary for comparison with cores data. By correlating data from other analysis (radiocarbon dating, benthic and planktonic δ18O records, geochemical, pollen, diatom analyses) with discovered foraminifera sample data (core 936), we established certain climatic patterns and defined 5 criteria to apply to all of the other cores that did not have the same depth of climate information. We find that variation in abundance of different morhpotypes allows determining period of cooling and warming, which is confirmed by the variation in abundance across all of foraminifera species. These criteria might be a solution for paleotemerature reconstruction using planktonic foraminifera.

Benthic hydroids (Cnidaria, Hydrozoa) from bathyal and abyssal depths of the Northeast Atlantic held in the modern Discovery Collections.

PubMed

Cantero, Álvaro L Peña; Horton, Tammy

2017-11-10

The deep-sea benthic hydroid fauna remains poorly known, in part because of less frequent sampling than the shelf fauna, in part owing to the immense study area, and partly also because available samples have been little studied by experts. In order to correct this, deep-sea benthic hydroid material from the modern Discovery Collections has been studied. Samples come from localities in the North-East Atlantic including the Porcupine Seabight, Porcupine Abyssal Plain, Rockall Trough, Rockall Bank, and the Mid-Atlantic Ridge. Sixteen species belonging to 12 families and 16 genera were found. Leptothecata are clearly dominant, being represented by 14 species; the remaining species belong to Anthoathecata. Lafoeidae and Tiarannidae are the most diverse families with three species each; the remaining families being represented by a single species. The low species diversity is remarkable at the generic level, with each genus being represented by a single species. Hydroid occurrence is low: twelve species were found in ≤ 9% of stations; Amphinema biscayana has the highest occurrence (27% of stations). Fifteen species were recorded in the Porcupine Seabight, two in the Rockall Trough, one at Rockall Bank, one on the Porcupine Abyssal Plain, and two at the Mid-Atlantic Ridge. The known bathymetric range for a third of the species is extended; the increase is particularly noteworthy in Amphinema biscayana, Acryptolaria crassicaulis, Clytia gigantea and Schizotricha profunda. Two distinct bathymetric groups are recognized: strictly deep-sea inhabitants and eurybathic species. Most species are globally distributed, some are widely distributed in the Atlantic, and others are limited to the North Atlantic or the Northeast Atlantic.

Interpreting carnivore scent-station surveys

USGS Publications Warehouse

Sargeant, G.A.; Johnson, D.H.; Berg, W.E.

1998-01-01

The scent-station survey method has been widely used to estimate trends in carnivore abundance. However, statistical properties of scent-station data are poorly understood, and the relation between scent-station indices and carnivore abundance has not been adequately evaluated. We assessed properties of scent-station indices by analyzing data collected in Minnesota during 1986-03. Visits to stations separated by <2 km were correlated for all species because individual carnivores sometimes visited several stations in succession. Thus, visits to stations had an intractable statistical distribution. Dichotomizing results for lines of 10 stations (0 or 21 visits) produced binomially distributed data that were robust to multiple visits by individuals. We abandoned 2-way comparisons among years in favor of tests for population trend, which are less susceptible to bias, and analyzed results separately for biogeographic sections of Minnesota because trends differed among sections. Before drawing inferences about carnivore population trends, we reevaluated published validation experiments. Results implicated low statistical power and confounding as possible explanations for equivocal or conflicting results of validation efforts. Long-term trends in visitation rates probably reflect real changes in populations, but poor spatial and temporal resolution, susceptibility to confounding, and low statistical power limit the usefulness of this survey method.

Changes in the physico-chemical properties of Amazonian aerosols from background conditions due to urban impacts in Central Amazonia.

NASA Astrophysics Data System (ADS)

Artaxo, P.; Barbosa, H. M.; Brito, J.; Carbone, S.; Fiorese, C.; Andre, B.; Rizzo, L. V.; Ditas, F.; Pöhlker, C.; Pöhlker, M. L.; Saturno, J.; Holanda, B. A.; Wang, J.; Souza, R. A. F. D.; Machado, L.; Andreae, M. O.; Martin, S. T.

2016-12-01

The GoAmazon 2014/15 experiment (Observations and Modeling of the Green Ocean Amazon) was a great opportunity to study how urbanization can change aerosol properties under pristine conditions in a tropical rain forest. The experiment took place from January 2014 to December 2015 in the vicinity of Manaus, Brazil, where several sampling stations were operated. Natural biogenic aerosol properties were studied in 3 sampling stations upwind of Manaus (ATTO (T0a), ZF2 (T0z) and EMBRAPA (T0e)). Urban impacted aerosols were analysed in two downwind sampling stations at Tiwa (T2) and Manacapuru (T3). Properties analysed were size distribution, scattering and absorption, composition, vertical profiles and others. Remote sensing measurements were done using AERONET and MODIS, while extensive ground based measurements were done in all sampling stations. Remote sensing measurements shows important changes in aerosol optical depth (AOD), especially in the aerosol absorption component. It was also observed a reduction in cloud droplet size downwind of Manaus for liquid phase clouds. Changes in particle number and size were also very significant, that reflected in changes in the aerosol radiative forcing (RF) before and after Manaus plume. In the dry season, an average RF of -24 w/m² was observed upwind, while -17 w/m² was observed downwind, due to large scale biomass burning aerosols. Single scattering albedo (SSA) at 550 nm changed from a high value of 0.96 upwind to 0.84 downwind due to the increase in absorbing aerosols in the wet season. In the dry season, SSA at 550nm changed from 0.95 to 0.87. Aerosol composition showed a large dominance of organic aerosols for all sites, accounting for 65-75% of PM1 non refractory aerosol. Most of these were secondary organic aerosol (SOA), with very low sulfate and nitrate concentrations. The influence of the Manaus plume on aerosol properties was more intense during the wet season, because in the dry season a significant amount of large scale biomass burning aerosol was observed for all GoAmazon 2014/15 sites.

Distribution of mercury in the environment at Almaden, Spain

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hildebrand, S.G.; Huckabee, J.W.; Diaz, F.S.

1980-10-01

An ecological survey of the concentration and distribution of mercury in terrestrial and aquatic systems near the mercury mine at Almaden, Spain, was initiated in 1974. Field studies were completed in 1977, and chemical analyses were completed in 1979. Sample collection at Almaden followed a trophic-level approach in which certain compartments were sampled at a given instant in time (fall 1974, fall 1975, spring 1976, fall 1976, spring 1977). Mean total mercury concentration in terrestrial plants (8 taxa combined) ranged from >100 ..mu..g/g within 0.5 km of the mine to 1 ..mu..g/g 20 km distant from the mine. Different plantmore » species had different affinities for mercury, but moss species usually had higher total mercury concentration than vascular plants. Woody plants were lower in mercury concentration than forbs. Total mercury concentration in muscle, brain, kidney, and liver tissue from mice was highest at a station near the stream receiving liquid effluent from the mine (mean total mercury at this station ranging from 0.18 ..mu..g/g in muscle to 4.74 ..mu..g/g in kidney). Approximately 15 to 30% of total mercury in mouse tissue was in the methylated form. Total mercury concentration in muscle tissue from house sparrows varied inversely with distance from the mine, with highest concentrations exceeding 0.1 ..mu..g/g. Approximately 1 to 4% of total mercury in sparrow muscle was in the methylated form.« less

Applications of synchrotron μ-XRF to study the distribution of biologically important elements in different environmental matrices: a review.

PubMed

Majumdar, Sanghamitra; Peralta-Videa, Jose R; Castillo-Michel, Hiram; Hong, Jie; Rico, Cyren M; Gardea-Torresdey, Jorge L

2012-11-28

Environmental matrices including soils, sediments, and living organisms are reservoirs of several essential as well as non-essential elements. Accurate qualitative and quantitative information on the distribution and interaction of biologically significant elements is vital to understand the role of these elements in environmental and biological samples. Synchrotron micro-X-ray fluorescence (μ-SXRF) allows in situ mapping of biologically important elements at nanometer to sub-micrometer scale with high sensitivity, negligible sample damage and enable tuning of the incident energy as desired. Beamlines in the synchrotron facilities are rapidly increasing their analytical versatility in terms of focusing optics, detector technologies, incident energy, and sample environment. Although extremely competitive, it is now feasible to find stations offering complimentary techniques like micro-X-ray diffraction (μ-XRD) and micro-X-ray absorption spectroscopy (μ-XAS) that will allow a more complete characterization of complex matrices. This review includes the most recent literature on the emerging applications and challenges of μ-SXRF in studying the distribution of biologically important elements and manufactured nanoparticles in soils, sediments, plants, and microbes. The advantages of using μ-SXRF and complimentary techniques in contrast to conventional techniques used for the respective studies are discussed. Copyright © 2012 Elsevier B.V. All rights reserved.

Modeling extreme PM10 concentration in Malaysia using generalized extreme value distribution

NASA Astrophysics Data System (ADS)

Hasan, Husna; Mansor, Nadiah; Salleh, Nur Hanim Mohd

2015-05-01

Extreme PM10 concentration from the Air Pollutant Index (API) at thirteen monitoring stations in Malaysia is modeled using the Generalized Extreme Value (GEV) distribution. The data is blocked into monthly selection period. The Mann-Kendall (MK) test suggests a non-stationary model so two models are considered for the stations with trend. The likelihood ratio test is used to determine the best fitted model and the result shows that only two stations favor the non-stationary model (Model 2) while the other eleven stations favor stationary model (Model 1). The return level of PM10 concentration that is expected to exceed the maximum once within a selected period is obtained.

A systematic intercomparison of regional flood frequency analysis models in a simulation framework

NASA Astrophysics Data System (ADS)

Ganora, Daniele; Laio, Francesco; Claps, Pierluigi

2015-04-01

Regional frequency analysis (RFA) is a well-established methodology to provide an estimate of the flood frequency curve (or other discharge-related variables), based on the fundamental concept of substituting temporal information at a site (no data or short time series) by exploiting observations at other sites (spatial information). Different RFA paradigms exist, depending on the way the information is transferred to the site of interest. Despite the wide use of such methodology, a systematic comparison between these paradigms has not been performed. The aim of this study is to provide a framework wherein carrying out the intercomparison: we thus synthetically generate data through Monte Carlo simulations for a number of (virtual) stations, following a GEV parent distribution; different scenarios can be created to represent different spatial heterogeneity patterns by manipulating the parameters of the parent distribution at each station (e.g. with a linear variation in space of the shape parameter of the GEV). A special case is the homogeneous scenario where each station record is sampled from the same parent distribution. For each scenario and each simulation, different regional models are applied to evaluate the 200-year growth factor at each station. Results are than compared to the exact growth factor of each station, which is known in our virtual world. Considered regional approaches include: (i) a single growth curve for the whole region; (ii) a multiple-region model based on cluster analysis which search for an adequate number of homogeneous subregions; (iii) a Region-of-Influence model which defines a homogeneous subregion for each site; (iv) a spatially-smooth estimation procedure based on linear regressions.. A further benchmark model is the at-site estimate based on the analysis of the local record. A comprehensive analysis of the results of the simulations shows that, if the scenario is homogeneous (no spatial variability), all the regional approaches have comparable performances. Moreover, as expected, regional estimates are much more reliable than the at-site estimates. If the scenario is heterogeneous, the performances of the regional models depend on the pattern of heterogeneity; in general, however, the spatially-smooth regional approach performs better than the others, and its performances improve for increasing record lengths. For heterogeneous scenarios, the at-site estimates appear to be comparably more efficient than in the homogeneous case, and in general less biased than the regional estimates.

KSC-99pp1379

NASA Image and Video Library

1999-12-02

KENNEDY SPACE CENTER, FLA. -- In the Space Station Processing Facility, STS-102's Expedition II discuss the Pressurized Mating Adapter (PMA-3) (top of photo) with workers from Johnson Space Center. From left are Yuriy Vladimirovich Usachev, Dave Moore (JSC), Susan J. Helms, James S. Voss, Arne Aamodt and Matt Myers (both of JSC). The PMA-3 is a component of the International Space Station (ISS). Voss, Helms and Usachev will be staying on the ISS, replacing the Expedition I crew, Bill Shepherd, Sergei Krikalev and Yuri Gidzenko. Along with the crew, Mission STS-102 also will be carrying the Leonardo Multi-Purpose Logistics Module (MPLM) to the ISS. The Leonardo will be filled with equipment and supplies to outfit the U.S. laboratory module, which will have been carried to the ISS on a preceding Shuttle flight. In order to function as an attached station module as well as a cargo transport, logistics modules (there are three) also include components that provide some life support, fire detection and suppression, electrical distribution and computer functions. Eventually, the modules also will carry refrigerator freezers for transporting experiment samples and food to and from the station. STS-102 is scheduled to launch no earlier than Oct. 19, 2000, from Launch Pad 39A, Kennedy Space Center

KSC-99pp1380

NASA Image and Video Library

1999-12-02

KENNEDY SPACE CENTER, FLA. -- In the Space Station Processing Facility, members of the STS-102 crew pose with workers from Johnson Space Center in front of the Pressurized Mating Adapter (PMA-3), a component of the International Space Station (ISS). From left are Dave Moore (JSC), Susan J. Helms, Arne Aamodt (JSC), Yuriy Vladimirovich Usachev, Matt Myers (JSC) and James S. Voss. Voss, Helms and Usachev, known as the Expedition II crew, will be staying on the ISS, replacing the Expedition I crew, Bill Shepherd, Sergei Krikalev and Yuri Gidzenko. Along with the crew, Mission STS-102 also will be carrying the Leonardo Multi-Purpose Logistics Module (MPLM) to the ISS. The Leonardo will be filled with equipment and supplies to outfit the U.S. laboratory module, which will have been carried to the ISS on a preceding Shuttle flight. In order to function as an attached station module as well as a cargo transport, logistics modules (there are three) also include components that provide some life support, fire detection and suppression, electrical distribution and computer functions. Eventually, the modules also will carry refrigerator freezers for transporting experiment samples and food to and from the station. STS-102 is scheduled to launch no earlier than Oct. 19, 2000, from Launch Pad 39A, Kennedy Space Center

[Airborne microflora found in some stations of the metro in the Hungarian capital of Budapest (author's transl)].

PubMed

Szám, L; Nikodemusz, I; Csatai, L; Vedres, I; Dákay, M

1980-02-01

Both the microflora and some physical parameters of the air in three underground railway (metro) stations were analysed. The air samples taken in the first two stations contained considerably more microbes, namely three times as many, than the sample from station No. 3. In the samples from the first two stations both the pathogenic and anthropogenic germs occured more frequently than in the samples from the third station. The normal flora consisted of gram-positive cocci/Streptococci, Micrococci, Sarcina. Roughly 10 per cent of the microbes proved to be spore-formers. Selective investigations led to the detection of Staph. aureus, Enterococci, Haemophilus influenzae, Escherichiae, Klebsiella and Proteus bacteria. The reason why the stations of line 2 were found to be contaminated to a greater degree is probably because of the higher passenger traffic, the smaller space, as well as the stronger airflow due to the artificial ventilation and the piston effect of the trains. The effect of the artificial environmental conditions on the staff of the metro company still needs further investigation. The effect on the passengers is considered to be less pronounced.

On-site phytoremediation applicability assessment in Alur Ilmu, Universiti Kebangsaan Malaysia based on spatial and pollution removal analyses.

PubMed

Mahmud, Mohd Hafiyyan; Lee, Khai Ern; Goh, Thian Lai

2017-10-01

The present paper aims to assess the phytoremediation performance based on pollution removal efficiency of the highly polluted region of Alur Ilmu urban river for its applicability of on-site treatment. Thirteen stations along Alur Ilmu were selected to produce thematic maps through spatial distribution analysis based on six water quality parameters of Malaysia's Water Quality Index (WQI) for dry and raining seasons. The maps generated were used to identify the highly polluted region for phytoremediation applicability assessment. Four free-floating plants were tested in treating water samples from the highly polluted region under three different conditions, namely controlled, aerated and normal treatments. The selected free-floating plants were water hyacinth (Eichhornia crassipes), water lettuce (Pistia stratiotes), rose water lettuce (Pistia sp.) and pennywort (Centella asiatica). The results showed that Alur Ilmu was more polluted during dry season compared to raining season based on the water quality analysis. During dry season, four parameters were marked as polluted along Alur Ilmu, namely dissolve oxygen (DO), 4.72 mg/L (class III); ammoniacal nitrogen (NH 3 -N), 0.85 mg/L (class IV); total suspended solid (TSS), 402 mg/L (class V) and biological oxygen demand (BOD), 3.89 mg/L (class III), whereas, two parameters were classed as polluted during raining season, namely total suspended solid (TSS), 571 mg/L (class V) and biological oxygen demand (BOD), 4.01 mg/L (class III). The thematic maps generated from spatial distribution analysis using Kriging gridding method showed that the highly polluted region was recorded at station AL 5. Hence, water samples were taken from this station for pollution removal analysis. All the free-floating plants were able to reduce TSS and COD in less than 14 days. However, water hyacinth showed the least detrimental effect from the phytoremediation process compared to other free-floating plants, thus made it a suitable free-floating plants to be used for on-site treatment.

Fitting monthly Peninsula Malaysian rainfall using Tweedie distribution

NASA Astrophysics Data System (ADS)

Yunus, R. M.; Hasan, M. M.; Zubairi, Y. Z.

2017-09-01

In this study, the Tweedie distribution was used to fit the monthly rainfall data from 24 monitoring stations of Peninsula Malaysia for the period from January, 2008 to April, 2015. The aim of the study is to determine whether the distributions within the Tweedie family fit well the monthly Malaysian rainfall data. Within the Tweedie family, the gamma distribution is generally used for fitting the rainfall totals, however the Poisson-gamma distribution is more useful to describe two important features of rainfall pattern, which are the occurrences (dry months) and the amount (wet months). First, the appropriate distribution of the monthly rainfall was identified within the Tweedie family for each station. Then, the Tweedie Generalised Linear Model (GLM) with no explanatory variable was used to model the monthly rainfall data. Graphical representation was used to assess model appropriateness. The QQ plots of quantile residuals show that the Tweedie models fit the monthly rainfall data better for majority of the stations in the west coast and mid land than those in the east coast of Peninsula. This significant finding suggests that the best fitted distribution depends on the geographical location of the monitoring station. In this paper, a simple model is developed for generating synthetic rainfall data for use in various areas, including agriculture and irrigation. We have showed that the data that were simulated using the Tweedie distribution have fairly similar frequency histogram to that of the actual data. Both the mean number of rainfall events and mean amount of rain for a month were estimated simultaneously for the case that the Poisson gamma distribution fits the data reasonably well. Thus, this work complements previous studies that fit the rainfall amount and the occurrence of rainfall events separately, each to a different distribution.

Analysis of phosphorus trends and evaluation of sampling designs in the Quinebaug River Basin, Connecticut

USGS Publications Warehouse

Todd Trench, Elaine C.

2004-01-01

A time-series analysis approach developed by the U.S. Geological Survey was used to analyze trends in total phosphorus and evaluate optimal sampling designs for future trend detection, using long-term data for two water-quality monitoring stations on the Quinebaug River in eastern Connecticut. Trend-analysis results for selected periods of record during 1971?2001 indicate that concentrations of total phosphorus in the Quinebaug River have varied over time, but have decreased significantly since the 1970s and 1980s. Total phosphorus concentrations at both stations increased in the late 1990s and early 2000s, but were still substantially lower than historical levels. Drainage areas for both stations are primarily forested, but water quality at both stations is affected by point discharges from municipal wastewater-treatment facilities. Various designs with sampling frequencies ranging from 4 to 11 samples per year were compared to the trend-detection power of the monthly (12-sample) design to determine the most efficient configuration of months to sample for a given annual sampling frequency. Results from this evaluation indicate that the current (2004) 8-sample schedule for the two Quinebaug stations, with monthly sampling from May to September and bimonthly sampling for the remainder of the year, is not the most efficient 8-sample design for future detection of trends in total phosphorus. Optimal sampling schedules for the two stations differ, but in both cases, trend-detection power generally is greater among 8-sample designs that include monthly sampling in fall and winter. Sampling designs with fewer than 8 samples per year generally provide a low level of probability for detection of trends in total phosphorus. Managers may determine an acceptable level of probability for trend detection within the context of the multiple objectives of the state?s water-quality management program and the scientific understanding of the watersheds in question. Managers may identify a threshold of probability for trend detection that is high enough to justify the agency?s investment in the water-quality sampling program. Results from an analysis of optimal sampling designs can provide an important component of information for the decision-making process in which sampling schedules are periodically reviewed and revised. Results from the study described in this report and previous studies indicate that optimal sampling schedules for trend detection may differ substantially for different stations and constituents. A more comprehensive statewide evaluation of sampling schedules for key stations and constituents could provide useful information for any redesign of the schedule for water-quality monitoring in the Quinebaug River Basin and elsewhere in the state.

Modeling annual extreme temperature using generalized extreme value distribution: A case study in Malaysia

NASA Astrophysics Data System (ADS)

Hasan, Husna; Salam, Norfatin; Kassim, Suraiya

2013-04-01

Extreme temperature of several stations in Malaysia is modeled by fitting the annual maximum to the Generalized Extreme Value (GEV) distribution. The Augmented Dickey Fuller (ADF) and Phillips Perron (PP) tests are used to detect stochastic trends among the stations. The Mann-Kendall (MK) test suggests a non-stationary model. Three models are considered for stations with trend and the Likelihood Ratio test is used to determine the best-fitting model. The results show that Subang and Bayan Lepas stations favour a model which is linear for the location parameters while Kota Kinabalu and Sibu stations are suitable with a model in the logarithm of the scale parameters. The return level is the level of events (maximum temperature) which is expected to be exceeded once, on average, in a given number of years, is obtained.

Orion Navigation Sensitivities to Ground Station Infrastructure for Lunar Missions

NASA Technical Reports Server (NTRS)

Getchius, Joel; Kukitschek, Daniel; Crain, Timothy

2008-01-01

The Orion Crew Exploration Vehicle (CEV) will replace the Space Shuttle and serve as the next-generation spaceship to carry humans to the International Space Station and back to the Moon for the first time since the Apollo program. As in the Apollo and Space Shuttle programs, the Mission Control Navigation team will utilize radiometric measurements to determine the position and velocity of the CEV. In the case of lunar missions, the ground station infrastructure consisting of approximately twelve stations distributed about the Earth and known as the Apollo Manned Spaceflight Network, no longer exists. Therefore, additional tracking resources will have to be allocated or constructed to support mission operations for Orion lunar missions. This paper examines the sensitivity of Orion navigation for lunar missions to the number and distribution of tracking sites that form the ground station infrastructure.

Linking hydrodynamic complexity to delta smelt (Hypomesus transpacificus) distribution in the San Francisco Estuary, USA

USGS Publications Warehouse

Bever, Aaron J.; MacWilliams, Michael L.; Herbold, Bruce; Brown, Larry R.; Feyrer, Frederick V.

2016-01-01

Long-term fish sampling data from the San Francisco Estuary were combined with detailed three dimensional hydrodynamic modeling to investigate the relationship between historical fish catch and hydrodynamic complexity. Delta Smelt catch data at 45 stations from the Fall Midwater Trawl (FMWT) survey in the vicinity of Suisun Bay were used to develop a quantitative catch-based station index. This index was used to rank stations based on historical Delta Smelt catch. The correlations between historical Delta Smelt catch and 35 quantitative metrics of environmental complexity were evaluated at each station. Eight metrics of environmental conditions were derived from FMWT data and 27 metrics were derived from model predictions at each FMWT station. To relate the station index to conceptual models of Delta Smelt habitat, the metrics were used to predict the station ranking based on the quantified environmental conditions. Salinity, current speed, and turbidity metrics were used to predict the relative ranking of each station for Delta Smelt catch. Including a measure of the current speed at each station improved predictions of the historical ranking for Delta Smelt catch relative to similar predictions made using only salinity and turbidity. Current speed was also found to be a better predictor of historical Delta Smelt catch than water depth. The quantitative approach developed using the FMWT data was validated using the Delta Smelt catch data from the San Francisco Bay Study. Complexity metrics in Suisun Bay were-evaluated during 2010 and 2011. This analysis indicated that a key to historical Delta Smelt catch is the overlap of low salinity, low maximum velocity, and low Secchi depth regions. This overlap occurred in Suisun Bay during 2011, and may have contributed to higher Delta Smelt abundance in 2011 than in 2010 when the favorable ranges of the metrics did not overlap in Suisun Bay.

Universal inverse power-law distribution for temperature and rainfall in the UK region

NASA Astrophysics Data System (ADS)

Selvam, A. M.

2014-06-01

Meteorological parameters, such as temperature, rainfall, pressure, etc., exhibit selfsimilar space-time fractal fluctuations generic to dynamical systems in nature such as fluid flows, spread of forest fires, earthquakes, etc. The power spectra of fractal fluctuations display inverse power-law form signifying long-range correlations. A general systems theory model predicts universal inverse power-law form incorporating the golden mean for the fractal fluctuations. The model predicted distribution was compared with observed distribution of fractal fluctuations of all size scales (small, large and extreme values) in the historic month-wise temperature (maximum and minimum) and total rainfall for the four stations Oxford, Armagh, Durham and Stornoway in the UK region, for data periods ranging from 92 years to 160 years. For each parameter, the two cumulative probability distributions, namely cmax and cmin starting from respectively maximum and minimum data value were used. The results of the study show that (i) temperature distributions (maximum and minimum) follow model predicted distribution except for Stornowy, minimum temperature cmin. (ii) Rainfall distribution for cmin follow model predicted distribution for all the four stations. (iii) Rainfall distribution for cmax follows model predicted distribution for the two stations Armagh and Stornoway. The present study suggests that fractal fluctuations result from the superimposition of eddy continuum fluctuations.

47 CFR 74.882 - Station identification.

Code of Federal Regulations, 2010 CFR

2010-10-01

... transmission or intermittent transmissions pertaining to a single event. (b) Each wireless video assist device..., AUXILIARY, SPECIAL BROADCAST AND OTHER PROGRAM DISTRIBUTIONAL SERVICES Low Power Auxiliary Stations § 74.882 Station identification. (a) For transmitters used for voice transmissions and having a transmitter output...

47 CFR 74.789 - Broadcast regulations applicable to digital low power television and television translator stations.

Code of Federal Regulations, 2011 CFR

2011-10-01

... AND OTHER PROGRAM DISTRIBUTIONAL SERVICES Low Power TV, TV Translator, and TV Booster Stations § 74... applicable to translators, low power, and booster stations (except § 73.653—Operation of TV aural and visual...

47 CFR 74.789 - Broadcast regulations applicable to digital low power television and television translator stations.

Code of Federal Regulations, 2013 CFR

2013-10-01

... AND OTHER PROGRAM DISTRIBUTIONAL SERVICES Low Power TV, TV Translator, and TV Booster Stations § 74... applicable to translators, low power, and booster stations (except § 73.653—Operation of TV aural and visual...

47 CFR 74.789 - Broadcast regulations applicable to digital low power television and television translator stations.

Code of Federal Regulations, 2014 CFR

2014-10-01

... AND OTHER PROGRAM DISTRIBUTIONAL SERVICES Low Power TV, TV Translator, and TV Booster Stations § 74... applicable to translators, low power, and booster stations (except § 73.653—Operation of TV aural and visual...

47 CFR 74.789 - Broadcast regulations applicable to digital low power television and television translator stations.

Code of Federal Regulations, 2012 CFR

2012-10-01

... AND OTHER PROGRAM DISTRIBUTIONAL SERVICES Low Power TV, TV Translator, and TV Booster Stations § 74... applicable to translators, low power, and booster stations (except § 73.653—Operation of TV aural and visual...

47 CFR 74.1203 - Interference.

Code of Federal Regulations, 2010 CFR

2010-10-01

..., AUXILIARY, SPECIAL BROADCAST AND OTHER PROGRAM DISTRIBUTIONAL SERVICES FM Broadcast Translator Stations and FM Broadcast Booster Stations § 74.1203 Interference. (a) An authorized FM translator or booster... transmission of any authorized broadcast station; or (2) The reception of the input signal of any TV translator...

[Distribution of airborne fungi, particulate matter and carbon dioxide in Seoul metropolitan subway stations].

PubMed

Kim, Ki Youn; Park, Jae Beom; Kim, Chi Nyon; Lee, Kyung Jong

2006-07-01

The aims of this study were to examine the level of airborne fungi and environmental factors in Seoul metropolitan subway stations and to provide fundamental data to protect the health of subway workers and passengers. The field survey was performed from November in 2004 to February in 2005. A total 22 subway stations located at Seoul subway lines 1-4 were randomly selected. The measurement points were subway workers' activity areas (station office, bedroom, ticket office and driver's seat) and the passengers' activity areas (station precincts, inside train and platform). Air sampling for collecting airborne fungi was carried out using a one-stage cascade impactor. The PM and CO2 were measured using an electronic direct recorder and detecting tube, respectively. In the activity areas of the subway workers and passengers, the mean concentrations of airborne fungi were relatively higher in the workers' bedroom and station precinct whereas the concentration of particulate matter, PM10 and PM2.5, were relatively higher in the platform, inside the train and driver's seat than in the other activity areas. There was no significant difference in the concentration of airborne fungi between the underground and ground activity areas of the subway. The mean PM10 and PM2.5 concentration in the platform located at underground was significantly higher than that of the ground (p<0.05). The levels of airborne fungi in the Seoul subway line 1-4 were not serious enough to cause respiratory disease in subway workers and passengers. This indicates that there is little correlation between airborne fungi and particulate matter.

Water resources data for Kansas, water year 1973; Part 2, Water quality records

USGS Publications Warehouse

Diaz, A.M.; Albert, C.D.

1974-01-01

Water-resources data for the 1973 water year for Kansas include records of data for the chemical and physical characteristics of surface and ground water. Data on the quality of surface water (chemical, microbiological, temperature, and sediment) were collected from designated sampling sites at predetermined intervals such as once daily, weekly, monthly, or less frequently, and at some sites data were recorded on punched paper tape at 60-minute intervals. Records are given for 70 sampling stations of which 7 are partial-record stations, and for 51 miscellaneous sites. Miscellaneous temperatures of streamflow are given for 77 gaging stations, and records of chemical analyses are given for 224 ground-water sites. Locations of surface water-quality stations are shown in Figure 1, page 2. Records for pertinent water-quality stations in bordering States are also included. The records were collected by the Water Resources Division of the U.S. Geological Survey under the direction of C. W. Lane, district chief. These data represent that portion of the National Water Data System collected by the U.S. Geological Survey and cooperating State and Federal agencies in Kansas. Kansas District personnel who contributed significantly to the collection and preparation of data included in this report were: B. L. Day, L. R. Shelton, M. L. Penny, L. R. Stringer, and D. J. Dark (Kansas State Department of Health).The Geological Survey has published records of chemical quality, suspended sediment, and water temperatures since 1941 in annual series of water-supply papers entitled, "Quality of Surface Waters of the United States." Beginning with the 1964 water year, water-quality records also have been released by the Geological Survey in annual reports on a State-boundary basis. Distribution of these reports is limited; they are designed primarily for rapid release of data shortly after the end of the water year to meet local needs. These records will be published later in Geological Survey water-supply papers.

Mars rover/sample return mission requirements affecting space station

NASA Technical Reports Server (NTRS)

1988-01-01

The possible interfaces between the Space Station and the Mars Rover/Sample Return (MRSR) mission are defined. In order to constrain the scope of the report a series of seven design reference missions divided into three major types were assumed. These missions were defined to span the probable range of Space Station-MRSR interactions. The options were reduced, the MRSR sample handling requirements and baseline assumptions about the MRSR hardware and the key design features and requirements of the Space Station are summarized. Only the aspects of the design reference missions necessary to define the interfaces, hooks and scars, and other provisions on the Space Station are considered. An analysis of each of the three major design reference missions, is reported, presenting conceptual designs of key hardware to be mounted on the Space Station, a definition of weights, interfaces, and required hooks and scars.

Water column profiles of particulate inorganic carbon in the northeast subarctic Pacific Ocean

NASA Astrophysics Data System (ADS)

Sutton, J. N.; Bishop, J. K.; Martinez, E. J.; Weiss, G. A.; Weiss, A.; Derr, A.; Strubhar, W.; Robert, M.; Wood, T.

2013-12-01

High resolution and real-time measurement of particulate inorganic carbon (PIC) content in seawater is necessary to improve our spatial and temporal understanding of marine carbon flux and the possible effects of ocean acidification on the biological pump. On four occasions since August 2012, we have mapped PIC distribution from surface to bottom at 26 stations along the IOS-Canada Line P transect from western Vancouver Island, BC, Canada to Ocean Station PAPA, 50N 145W using a prototype (PIC001) and a near-commercial quality (PIC008) optical birefringence sensor. The sensors are highly modified 6000m-rated WETLabs C-star transmissometers, which use a polarized laser beam and a cross-polarized receiver to measure photons emitted after passing through birefringent solids. At major stations along Line P (P2, P4, P8, P12, P16, P20, P26), one-liter rosette-collected calibration water samples were filtered through 0.45 μm Supor filters using a small-volume direct filtration system. These samples were analysed for acid-leachable particulate elements (with emphasis on Ca, Na, and Mg) by inductively coupled plasma mass spectrometry (ICPMS). ICPMS PIC was calculated as residual Ca after correction for seawater Ca using Na data. Here we report results for late summer (Aug. 2012) and winter (Feb. 2013). As expected, high levels of PIC (> 100 nmol L-1 to > 2000 nmol L-1) were found in surface waters but rapidly declined at depths greater than 200m and increased again in the nepheloid layer (>50 nmol L-1). Striking seasonal differences in PIC content and PIC profile shape were observed particularly at near shore stations P2, P4, P8 and P12. The results from this research, including sensor evolution and calibration performance, will be presented.

Organochlorine chemical residues in fish from the Mississippi River basin, 1995

USGS Publications Warehouse

Schmitt, C.J.

2002-01-01

Fish were collected in late 1995 from 34 National Contaminant Biomonitoring Program (NCBP) stations and 13 National Water Quality Assessment Program (NAWQA) stations in the Mississippi River basin (MRB) and in late 1996 from a reference site in West Virginia. Four composite samples, each comprising (nominally) 10 adult common carp (Cyprinus carpio) or black bass (Micropterus spp.) of the same sex, were collected from each site and analyzed for organochlorine chemical residues by gas chromatography with electron capture detection. At the NCBP stations, which are located on relatively large rivers, concentrations of organochlorine chemical residues were generally lower than when last sampled in the mid-1980s. Residues derived from DDT (primarily p,p???-DDE) were detected at all sites (including the reference site); however, only traces (??? 0.02 ??g/g) of the parent insecticide (p,p???-DDT) were present, which indicates continued weathering of residual DDT from past use. Nevertheless, concentrations of DDT (as p,p???-DDE) in fish from the cotton-farming regions of the lower MRB were great enough to constitute a hazard to fish-eating wildlife and were especially high at the NAWQA sites on the lower-order rivers and streams of the Mississippi embayment. Mirex was detected at only two sites, both in Louisiana, and toxaphene was found exclusively in the lower MRB. Most cyclodiene pesticides (dieldrin, chlordane, and heptachlor epoxide) were more widespread in their distributions, but concentrations were lower than in the 1980s except at a site on the Mississippi River near Memphis, TN. Concentrations were also somewhat elevated at sites in the Corn Belt. Endrin was detected exclusively at the Memphis site. PCB concentrations generally declined, and residues were detected (??? 0.05 ??g/g) at only 35% of the stations, mostly in the more industrialized parts of the MRB.

Experimental station for ultrafast extreme ultraviolet spectroscopy for non-equilibrium dynamics in warm dense matter

NASA Astrophysics Data System (ADS)

Lee, Jong-won; Geng, Xiaotao; Jung, Jae Hyung; Cho, Min Sang; Yang, Seong Hyeok; Jo, Jawon; Lee, Chang-lyoul; Cho, Byoung Ick; Kim, Dong-Eon

2018-07-01

Recent interest in highly excited matter generated by intense femtosecond laser pulses has led to experimental methods that directly investigate ultrafast non-equilibrium electronic and structural dynamics. We present a tabletop experimental station for the extreme ultraviolet (EUV) spectroscopy used to trace L-edge dynamics in warm dense aluminum with a temporal resolution of a hundred femtoseconds. The system consists of the EUV probe generation part via a high-order harmonic generation process of femtosecond laser pulses with atomic clusters, a beamline with high-throughput optics and a sample-refreshment system of nano-foils utilizing the full repetition rate of the probe, and a flat-field EUV spectrograph. With the accumulation of an order of a hundred shots, a clear observation of the change in the aluminum L-shell absorption was achieved with a temporal resolution of 90 fs in a 600-fs window. The signature of a non-equilibrium electron distribution over a 10-eV range and its evolution to a 1-eV Fermi distribution are observed. This demonstrates the capability of this apparatus to capture the non-equilibrium electron-hole dynamics in highly excited warm dense matter conditions.

Composite measures of watershed health from a water quality perspective.

PubMed

Mallya, Ganeshchandra; Hantush, Mohamed; Govindaraju, Rao S

2018-05-15

Water quality data at gaging stations are typically compared with established federal, state, or local water quality standards to determine if violations (concentrations of specific constituents falling outside acceptable limits) have occurred. Based on the frequency and severity of water quality violations, risk metrics such as reliability, resilience, and vulnerability (R-R-V) are computed for assessing water quality-based watershed health. In this study, a modified methodology for computing R-R-V measures is presented, and a new composite watershed health index is proposed. Risk-based assessments for different water quality parameters are carried out using identified national sampling stations within the Upper Mississippi River Basin, the Maumee River Basin, and the Ohio River Basin. The distributional properties of risk measures with respect to water quality parameters are reported. Scaling behaviors of risk measures using stream order, specifically for the watershed health (WH) index, suggest that WH values increased with stream order for suspended sediment concentration, nitrogen, and orthophosphate in the Upper Mississippi River Basin. Spatial distribution of risk measures enable identification of locations exhibiting poor watershed health with respect to the chosen numerical standard, and the role of land use characteristics within the watershed. Copyright © 2018 Elsevier Ltd. All rights reserved.

Automation of Space Station module power management and distribution system

NASA Technical Reports Server (NTRS)

Bechtel, Robert; Weeks, Dave; Walls, Bryan

1990-01-01

Viewgraphs on automation of space station module (SSM) power management and distribution (PMAD) system are presented. Topics covered include: reasons for power system automation; SSM/PMAD approach to automation; SSM/PMAD test bed; SSM/PMAD topology; functional partitioning; SSM/PMAD control; rack level autonomy; FRAMES AI system; and future technology needs for power system automation.

Reliability and sensitivity analysis of a system with multiple unreliable service stations and standby switching failures

NASA Astrophysics Data System (ADS)

Ke, Jyh-Bin; Lee, Wen-Chiung; Wang, Kuo-Hsiung

2007-07-01

This paper presents the reliability and sensitivity analysis of a system with M primary units, W warm standby units, and R unreliable service stations where warm standby units switching to the primary state might fail. Failure times of primary and warm standby units are assumed to have exponential distributions, and service times of the failed units are exponentially distributed. In addition, breakdown times and repair times of the service stations also follow exponential distributions. Expressions for system reliability, RY(t), and mean time to system failure, MTTF are derived. Sensitivity analysis, relative sensitivity analysis of the system reliability and the mean time to failure, with respect to system parameters are also investigated.

KENNEDY SPACE CENTER, FLA. - The Minus Eighty Lab Freezer for ISS (MELFI), provided as Laboratory Support Equipment by the European Space Agency for the International Space Station, is seen in the Space Station Processing Facility. The lab will provide cooling and storage for reagents, samples and perishable materials in four insulated containers called dewars with independently selectable temperatures of -80°C, -26°C, and +4°C. It also will be used to transport samples to and from the station. The MELFI is planned for launch on the ULF-1 mission.

NASA Image and Video Library

2003-09-08

KENNEDY SPACE CENTER, FLA. - The Minus Eighty Lab Freezer for ISS (MELFI), provided as Laboratory Support Equipment by the European Space Agency for the International Space Station, is seen in the Space Station Processing Facility. The lab will provide cooling and storage for reagents, samples and perishable materials in four insulated containers called dewars with independently selectable temperatures of -80°C, -26°C, and +4°C. It also will be used to transport samples to and from the station. The MELFI is planned for launch on the ULF-1 mission.

KENNEDY SPACE CENTER, FLA. - In the Space Station Processing Facility, technicians remove the cover from the Minus Eighty Lab Freezer for ISS(MELFI) provided as Laboratory Support Equipment by the European Space Agency for the International Space Station. The lab will provide cooling and storage for reagents, samples and perishable materials in four insulated containers called dewars with independently selectable temperatures of -80°C, -26°C, and +4°C. It also will be used to transport samples to and from the station. The MELFI is planned for launch on the ULF-1 mission.

NASA Image and Video Library

2003-09-08

KENNEDY SPACE CENTER, FLA. - In the Space Station Processing Facility, technicians remove the cover from the Minus Eighty Lab Freezer for ISS(MELFI) provided as Laboratory Support Equipment by the European Space Agency for the International Space Station. The lab will provide cooling and storage for reagents, samples and perishable materials in four insulated containers called dewars with independently selectable temperatures of -80°C, -26°C, and +4°C. It also will be used to transport samples to and from the station. The MELFI is planned for launch on the ULF-1 mission.

Ichthyoplankton abundance and variance in a large river system concerns for long-term monitoring

USGS Publications Warehouse

Holland-Bartels, Leslie E.; Dewey, Michael R.; Zigler, Steven J.

1995-01-01

System-wide spatial patterns of ichthyoplankton abundance and variability were assessed in the upper Mississippi and lower Illinois rivers to address the experimental design and statistical confidence in density estimates. Ichthyoplankton was sampled from June to August 1989 in primary milieus (vegetated and non-vegated backwaters and impounded areas, main channels and main channel borders) in three navigation pools (8, 13 and 26) of the upper Mississippi River and in a downstream reach of the Illinois River. Ichthyoplankton densities varied among stations of similar aquatic landscapes (milieus) more than among subsamples within a station. An analysis of sampling effort indicated that the collection of single samples at many stations in a given milieu type is statistically and economically preferable to the collection of multiple subsamples at fewer stations. Cluster analyses also revealed that stations only generally grouped by their preassigned milieu types. Pilot studies such as this can define station groupings and sources of variation beyond an a priori habitat classification. Thus the minimum intensity of sampling required to achieve a desired statistical confidence can be identified before implementing monitoring efforts.

Statistical distributions of extreme dry spell in Peninsular Malaysia

NASA Astrophysics Data System (ADS)

Zin, Wan Zawiah Wan; Jemain, Abdul Aziz

2010-11-01

Statistical distributions of annual extreme (AE) series and partial duration (PD) series for dry-spell event are analyzed for a database of daily rainfall records of 50 rain-gauge stations in Peninsular Malaysia, with recording period extending from 1975 to 2004. The three-parameter generalized extreme value (GEV) and generalized Pareto (GP) distributions are considered to model both series. In both cases, the parameters of these two distributions are fitted by means of the L-moments method, which provides a robust estimation of them. The goodness-of-fit (GOF) between empirical data and theoretical distributions are then evaluated by means of the L-moment ratio diagram and several goodness-of-fit tests for each of the 50 stations. It is found that for the majority of stations, the AE and PD series are well fitted by the GEV and GP models, respectively. Based on the models that have been identified, we can reasonably predict the risks associated with extreme dry spells for various return periods.

Low-flow analysis and selected flow statistics representative of 1930-2002 for streamflow-gaging stations in or near West Virginia

USGS Publications Warehouse

Wiley, Jeffrey B.

2006-01-01

Five time periods between 1930 and 2002 are identified as having distinct patterns of annual minimum daily mean flows (minimum flows). Average minimum flows increased around 1970 at many streamflow-gaging stations in West Virginia. Before 1930, however, there might have been a period of minimum flows greater than any period identified between 1930 and 2002. The effects of climate variability are probably the principal causes of the differences among the five time periods. Comparisons of selected streamflow statistics are made between values computed for the five identified time periods and values computed for the 1930-2002 interval for 15 streamflow-gaging stations. The average difference between statistics computed for the five time periods and the 1930-2002 interval decreases with increasing magnitude of the low-flow statistic. The greatest individual-station absolute difference was 582.5 percent greater for the 7-day 10-year low flow computed for 1970-1979 compared to the value computed for 1930-2002. The hydrologically based low flows indicate approximately equal or smaller absolute differences than biologically based low flows. The average 1-day 3-year biologically based low flow (1B3) and 4-day 3-year biologically based low flow (4B3) are less than the average 1-day 10-year hydrologically based low flow (1Q10) and 7-day 10-year hydrologic-based low flow (7Q10) respectively, and range between 28.5 percent less and 13.6 percent greater. Seasonally, the average difference between low-flow statistics computed for the five time periods and 1930-2002 is not consistent between magnitudes of low-flow statistics, and the greatest difference is for the summer (July 1-September 30) and fall (October 1-December 31) for the same time period as the greatest difference determined in the annual analysis. The greatest average difference between 1B3 and 4B3 compared to 1Q10 and 7Q10, respectively, is in the spring (April 1-June 30), ranging between 11.6 and 102.3 percent greater. Statistics computed for the individual station's record period may not represent the statistics computed for the period 1930 to 2002 because (1) station records are available predominantly after about 1970 when minimum flows were greater than the average between 1930 and 2002 and (2) some short-term station records are mostly during dry periods, whereas others are mostly during wet periods. A criterion-based sampling of the individual station's record periods at stations was taken to reduce the effects of statistics computed for the entire record periods not representing the statistics computed for 1930-2002. The criterion used to sample the entire record periods is based on a comparison between the regional minimum flows and the minimum flows at the stations. Criterion-based sampling of the available record periods was superior to record-extension techniques for this study because more stations were selected and areal distribution of stations was more widespread. Principal component and correlation analyses of the minimum flows at 20 stations in or near West Virginia identify three regions of the State encompassing stations with similar patterns of minimum flows: the Lower Appalachian Plateaus, the Upper Appalachian Plateaus, and the Eastern Panhandle. All record periods of 10 years or greater between 1930 and 2002 where the average of the regional minimum flows are nearly equal to the average for 1930-2002 are determined as representative of 1930-2002. Selected statistics are presented for the longest representative record period that matches the record period for 77 stations in West Virginia and 40 stations near West Virginia. These statistics can be used to develop equations for estimating flow in ungaged stream locations.

47 CFR 78.5 - Definitions.

Code of Federal Regulations, 2013 CFR

2013-10-01

...), and (d) of this section. (b) Local distribution service (LDS) station. A fixed CARS station used... headend of a cable television system. (d) Cable Television Relay Service PICKUP station. A land mobile.... For other definitions, see part 76 (Cable Television Service) of this chapter. (a) Cable television...

47 CFR 78.5 - Definitions.

Code of Federal Regulations, 2010 CFR

2010-10-01

...), and (d) of this section. (b) Local distribution service (LDS) station. A fixed CARS station used... headend of a cable television system. (d) Cable Television Relay Service PICKUP station. A land mobile.... For other definitions, see part 76 (Cable Television Service) of this chapter. (a) Cable television...

47 CFR 78.5 - Definitions.

Code of Federal Regulations, 2011 CFR

2011-10-01

...), and (d) of this section. (b) Local distribution service (LDS) station. A fixed CARS station used... headend of a cable television system. (d) Cable Television Relay Service PICKUP station. A land mobile.... For other definitions, see part 76 (Cable Television Service) of this chapter. (a) Cable television...

47 CFR 78.5 - Definitions.

Code of Federal Regulations, 2012 CFR

2012-10-01

...), and (d) of this section. (b) Local distribution service (LDS) station. A fixed CARS station used... headend of a cable television system. (d) Cable Television Relay Service PICKUP station. A land mobile.... For other definitions, see part 76 (Cable Television Service) of this chapter. (a) Cable television...

47 CFR 78.5 - Definitions.

Code of Federal Regulations, 2014 CFR

2014-10-01

...), and (d) of this section. (b) Local distribution service (LDS) station. A fixed CARS station used... headend of a cable television system. (d) Cable Television Relay Service PICKUP station. A land mobile.... For other definitions, see part 76 (Cable Television Service) of this chapter. (a) Cable television...

Cucurbit germplasm collections at the North Central Regional Plant Introduction Station

USDA-ARS?s Scientific Manuscript database

The North Central Regional Plant Introduction Station (NCRPIS) in Ames, Iowa, USA is one of four primary Plant Introduction Stations in the National Plant Germplasm System (NPGS), and has responsibility for maintenance, regeneration, characterization, and distribution of the NPGS Cucumis and Cucurbi...

47 CFR 74.1236 - Emission and bandwidth.

Code of Federal Regulations, 2011 CFR

2011-10-01

..., AUXILIARY, SPECIAL BROADCAST AND OTHER PROGRAM DISTRIBUTIONAL SERVICES FM Broadcast Translator Stations and FM Broadcast Booster Stations § 74.1236 Emission and bandwidth. (a) The license of a station...) apply. (b) Standard width FM channels will be assigned and the transmitting apparatus shall be operated...

Long-term changes (1980-2003) in total ozone time series over Northern Hemisphere midlatitudes

NASA Astrophysics Data System (ADS)

Białek, Małgorzata

2006-03-01

Long-term changes in total ozone time series for Arosa, Belsk, Boulder and Sapporo stations are examined. For each station we analyze time series of the following statistical characteristics of the distribution of daily ozone data: seasonal mean, standard deviation, maximum and minimum of total daily ozone values for all seasons. The iterative statistical model is proposed to estimate trends and long-term changes in the statistical distribution of the daily total ozone data. The trends are calculated for the period 1980-2003. We observe lessening of negative trends in the seasonal means as compared to those calculated by WMO for 1980-2000. We discuss a possibility of a change of the distribution shape of ozone daily data using the Kolmogorov-Smirnov test and comparing trend values in the seasonal mean, standard deviation, maximum and minimum time series for the selected stations and seasons. The distribution shift toward lower values without a change in the distribution shape is suggested with the following exceptions: the spreading of the distribution toward lower values for Belsk during winter and no decisive result for Sapporo and Boulder in summer.

Amount and distribution of neustonic micro-plastic off the western Sardinian coast (Central-Western Mediterranean Sea).

PubMed

de Lucia, Giuseppe Andrea; Caliani, Ilaria; Marra, Stefano; Camedda, Andrea; Coppa, Stefania; Alcaro, Luigi; Campani, Tommaso; Giannetti, Matteo; Coppola, Daniele; Cicero, Anna Maria; Panti, Cristina; Baini, Matteo; Guerranti, Cristiana; Marsili, Letizia; Massaro, Giorgio; Fossi, Maria Cristina; Matiddi, Marco

2014-09-01

A plethora of different sampling methodologies has been used to document the presence of micro-plastic fragments in sea water. European Marine Strategy suggests to improve standard techniques to make future data comparable. We use Manta Trawl sampling technique to quantify abundance and distribution of micro-plastic fragments in Sardinian Sea (Western Mediterranean), and their relation with phthalates and organoclorine in the neustonic habitat. Our results highlight a quite high average plastic abundance value (0.15 items/m(3)), comparable to the levels detected in other areas of the Mediterranean. "Site" is the only factor that significantly explains the differences observed in micro-plastic densities. Contaminant levels show high spatial and temporal variation. In every station, HCB is the contaminant with the lowest concentration while PCBs shows the highest levels. This work, in line with Marine Strategy directives, represents a preliminary study for the analysis of plastic impact on marine environment of Sardinia. Copyright © 2014 Elsevier Ltd. All rights reserved.

MISSE in the Materials and Processes Technical Information System (MAPTIS )

NASA Technical Reports Server (NTRS)

Burns, DeWitt; Finckenor, Miria; Henrie, Ben

2013-01-01

Materials International Space Station Experiment (MISSE) data is now being collected and distributed through the Materials and Processes Technical Information System (MAPTIS) at Marshall Space Flight Center in Huntsville, Alabama. MISSE data has been instrumental in many programs and continues to be an important source of data for the space community. To facilitate great access to the MISSE data the International Space Station (ISS) program office and MAPTIS are working to gather this data into a central location. The MISSE database contains information about materials, samples, and flights along with pictures, pdfs, excel files, word documents, and other files types. Major capabilities of the system are: access control, browsing, searching, reports, and record comparison. The search capabilities will search within any searchable files so even if the desired meta-data has not been associated data can still be retrieved. Other functionality will continue to be added to the MISSE database as the Athena Platform is expanded

Assessment and mitigation of errors associated with a large-scale field investigation of methane emissions from the Marcellus Shale

NASA Astrophysics Data System (ADS)

Caulton, D.; Golston, L.; Li, Q.; Bou-Zeid, E.; Pan, D.; Lane, H.; Lu, J.; Fitts, J. P.; Zondlo, M. A.

2015-12-01

Recent work suggests the distribution of methane emissions from fracking operations is a skewed distributed with a small percentage of emitters contributing a large proportion of the total emissions. In order to provide a statistically robust distributions of emitters and determine the presence of super-emitters, errors in current techniques need to be constrained and mitigated. The Marcellus shale, the most productive natural gas shale field in the United States, has received less intense focus for well-level emissions and is here investigated to provide the distribution of methane emissions. In July of 2015 approximately 250 unique well pads were sampled using the Princeton Atmospheric Chemistry Mobile Acquisition Node (PAC-MAN). This mobile lab includes a Garmin GPS unit, Vaisala weather station (WTX520), LICOR 7700 CH4 open path sensor and LICOR 7500 CO2/H2O open path sensor. Sampling sites were preselected based on wind direction, sampling distance and elevation grade. All sites were sampled during low boundary layer conditions (600-1000 and 1800-2200 local time). The majority of sites were sampled 1-3 times while selected test sites were sampled multiple times or resampled several times during the day. For selected sites a sampling tower was constructed consisting of a Metek uSonic-3 Class A sonic anemometer, and an additional LICOR 7700 and 7500. Data were recorded for at least one hour at these sites. A robust study and inter-comparison of different methodologies will be presented. The Gaussian plume model will be used to calculate fluxes for all sites and compare results from test sites with multiple passes. Tower data is used to provide constraints on the Gaussian plume model. Additionally, Large Eddy Simulation (LES) modeling will be used to calculate emissions from the tower sites. Alternative techniques will also be discussed. Results from these techniques will be compared to identify best practices and provide robust error estimates.

Real-time geomagnetic monitoring for space weather-related applications: Opportunities and challenges

USGS Publications Warehouse

Love, Jeffrey J.; Finn, Carol

2017-01-01

An examination is made of opportunities and challenges for enhancing global, real-time geomagnetic monitoring that would be beneficial for a variety of operational projects. This enhancement in geomagnetic monitoring can be attained by expanding the geographic distribution of magnetometer stations, improving the quality of magnetometer data, increasing acquisition sampling rates, increasing the promptness of data transmission, and facilitating access to and use of the data. Progress will benefit from new partnerships to leverage existing capacities and harness multisector, cross-disciplinary, and international interests.

[Composition, distribution and abundance of gastropod larvae in the South of Quintana Roo,Mexico and north of Belice].

PubMed

Oliva Rivera, J; de Jesús Navarrete, A

2000-12-01

To know the composition, abundance and distribution of gastropod larvae, monthly samplings were carried out in the south of Quintana Roo, Mexico and north of Belize, from April to December, 1996. Collections were made in six sites at Chinchorro Bank, four in the South Coast and six at Hol-Chan, Belize, between the 10 and 20 hrs. At each station 2.5 m3 of seawater were pumped through a 202 microns mesh; 27 species were identified. The most abundant species were: South Coast, Rissoina sp. 1., Limacina sp. 1 and Natica sp. 1, Chinchorro Bank, Limacina sp. 1, Creseis acicula, Cerithiopsis hero and Rissoina sp. 1 and Hol-Chan, Limacina sp. 2, Alaba incerta and Rissoina sp. 1. The highest abundance was in rainy season. Apparently the presence of winds, coastal currents and food availability, control the distribution and abundance of larvae.

Some key considerations in evolving a computer system and software engineering support environment for the space station program

NASA Technical Reports Server (NTRS)

Mckay, C. W.; Bown, R. L.

1985-01-01

The space station data management system involves networks of computing resources that must work cooperatively and reliably over an indefinite life span. This program requires a long schedule of modular growth and an even longer period of maintenance and operation. The development and operation of space station computing resources will involve a spectrum of systems and software life cycle activities distributed across a variety of hosts, an integration, verification, and validation host with test bed, and distributed targets. The requirement for the early establishment and use of an apporopriate Computer Systems and Software Engineering Support Environment is identified. This environment will support the Research and Development Productivity challenges presented by the space station computing system.

Web Information Systems for Monitoring and Control of Indoor Air Quality at Subway Stations

NASA Astrophysics Data System (ADS)

Choi, Gi Heung; Choi, Gi Sang; Jang, Joo Hyoung

In crowded subway stations indoor air quality (IAQ) is a key factor for ensuring the safety, health and comfort of passengers. In this study, a framework for web-based information system in VDN environment for monitoring and control of IAQ in subway stations is suggested. Since physical variables that describing IAQ need to be closely monitored and controlled in multiple locations in subway stations, concept of distributed monitoring and control network using wireless media needs to be implemented. Connecting remote wireless sensor network and device (LonWorks) networks to the IP network based on the concept of VDN can provide a powerful, integrated, distributed monitoring and control performance, making a web-based information system possible.

Direct measurements show decreasing methane emissions from natural gas local distribution systems in the United States.

PubMed

Lamb, Brian K; Edburg, Steven L; Ferrara, Thomas W; Howard, Touché; Harrison, Matthew R; Kolb, Charles E; Townsend-Small, Amy; Dyck, Wesley; Possolo, Antonio; Whetstone, James R

2015-04-21

Fugitive losses from natural gas distribution systems are a significant source of anthropogenic methane. Here, we report on a national sampling program to measure methane emissions from 13 urban distribution systems across the U.S. Emission factors were derived from direct measurements at 230 underground pipeline leaks and 229 metering and regulating facilities using stratified random sampling. When these new emission factors are combined with estimates for customer meters, maintenance, and upsets, and current pipeline miles and numbers of facilities, the total estimate is 393 Gg/yr with a 95% upper confidence limit of 854 Gg/yr (0.10% to 0.22% of the methane delivered nationwide). This fraction includes emissions from city gates to the customer meter, but does not include other urban sources or those downstream of customer meters. The upper confidence limit accounts for the skewed distribution of measurements, where a few large emitters accounted for most of the emissions. This emission estimate is 36% to 70% less than the 2011 EPA inventory, (based largely on 1990s emission data), and reflects significant upgrades at metering and regulating stations, improvements in leak detection and maintenance activities, as well as potential effects from differences in methodologies between the two studies.

Ice nucleating particles from a large-scale sampling network: insight into geographic and temporal variability

NASA Astrophysics Data System (ADS)

Schrod, Jann; Weber, Daniel; Thomson, Erik S.; Pöhlker, Christopher; Saturno, Jorge; Artaxo, Paulo; Curtius, Joachim; Bingemer, Heinz

2017-04-01

The number concentration of ice nucleating particles (INP) is an important, yet under quantified atmospheric parameter. The temporal and geographic extent of observations worldwide remains relatively small, with many regions of the world (even whole continents and oceans), almost completely unrepresented by observational data. Measurements at pristine sites are particularly rare, but all the more valuable because such observations are necessary to estimate the pre-industrial baseline of aerosol and cloud related parameters that are needed to better understand the climate system and forecast future scenarios. As a partner of BACCHUS we began in September 2014 to operate an INP measurement network of four sampling stations, with a global geographic distribution. The stations are located at unique sites reaching from the Arctic to the equator: the Amazonian Tall Tower Observatory ATTO in Brazil, the Observatoire Volcanologique et Sismologique on the island of Martinique in the Caribbean Sea, the Zeppelin Observatory at Svalbard in the Norwegian Arctic and the Taunus Observatory near Frankfurt, Germany. Since 2014 samples were collected regularly by electrostatic precipitation of aerosol particles onto silicon substrates. The INP on the substrate are activated and analyzed in the isothermal static diffusion chamber FRIDGE at temperatures between -20°C and -30°C and relative humidity with respect to ice from 115 to 135%. Here we present data from the years 2015 and 2016 from this novel INP network and from selected campaign-based measurements from remote sites, including the Mt. Kenya GAW station. Acknowledgements The research leading to these results has received funding from the European Union's Seventh Framework Programme (FP7/2007-2013) project BACCHUS under grant agreement No 603445 and the Deutsche Forschungsgemeinschaft (DFG) under the Research Unit FOR 1525 (INUIT).

Space Station Freedom power management and distribution design status

NASA Technical Reports Server (NTRS)

Javidi, S.; Gholdston, E.; Stroh, P.

1989-01-01

The design status of the power management and distribution electric power system for the Space Station Freedom is presented. The current design is a star architecture, which has been found to be the best approach for meeting the requirement to deliver 120 V dc to the user interface. The architecture minimizes mass and power losses while improving element-to-element isolation and system flexibility. The design is partitioned into three elements: energy collection, storage and conversion, system protection and distribution, and management and control.

Status of 20 kHz space station power distribution technology

NASA Technical Reports Server (NTRS)

Hansen, Irving G.

1988-01-01

Power Distribution on the NASA Space Station will be accomplished by a 20 kHz sinusoidal, 440 VRMS, single phase system. In order to minimize both system complexity and the total power coversion steps required, high frequency power will be distributed end-to-end in the system. To support the final design of flight power system hardware, advanced development and demonstrations have been made on key system technologies and components. The current status of this program is discussed.

OUTPACE long duration stations: physical variability, context of biogeochemical sampling, and evaluation of sampling strategy

NASA Astrophysics Data System (ADS)

de Verneil, Alain; Rousselet, Louise; Doglioli, Andrea M.; Petrenko, Anne A.; Maes, Christophe; Bouruet-Aubertot, Pascale; Moutin, Thierry

2018-04-01

Research cruises to quantify biogeochemical fluxes in the ocean require taking measurements at stations lasting at least several days. A popular experimental design is the quasi-Lagrangian drifter, often mounted with in situ incubations or sediment traps that follow the flow of water over time. After initial drifter deployment, the ship tracks the drifter for continuing measurements that are supposed to represent the same water environment. An outstanding question is how to best determine whether this is true. During the Oligotrophy to UlTra-oligotrophy PACific Experiment (OUTPACE) cruise, from 18 February to 3 April 2015 in the western tropical South Pacific, three separate stations of long duration (five days) over the upper 500 m were conducted in this quasi-Lagrangian sampling scheme. Here we present physical data to provide context for these three stations and to assess whether the sampling strategy worked, i.e., that a single body of water was sampled. After analyzing tracer variability and local water circulation at each station, we identify water layers and times where the drifter risks encountering another body of water. While almost no realization of this sampling scheme will be truly Lagrangian, due to the presence of vertical shear, the depth-resolved observations during the three stations show most layers sampled sufficiently homogeneous physical environments during OUTPACE. By directly addressing the concerns raised by these quasi-Lagrangian sampling platforms, a protocol of best practices can begin to be formulated so that future research campaigns include the complementary datasets and analyses presented here to verify the appropriate use of the drifter platform.

Probable LAGEOS contributions to a worldwide geodynamics control network

NASA Technical Reports Server (NTRS)

Bender, P. L.; Goad, C. C.

1979-01-01

The paper describes simulations performed on the contributions which LAGEOS laser ranging data can make to the establishment of a worldwide geodynamics control network. A distribution of 10 fixed ranging stations was assumed for most of the calculations, and a single 7-day arc was used, measurements assumed to be made every 10 minutes in order to avoid artificial reductions in the uncertainties due to oversampling. Computer simulations were carried out in which the coordinates of the stations and improvements in the gravity field coefficients were solved for simultaneously. It is suggested that good accuracy for station coordinates can be expected, even with the present gravity field model uncertainties, if sufficient measurement accuracy is achieved at a reasonable distribution of stations. Further, it is found that even 2-cm range measurement errors would be likely to be the main source of station coordinate errors in retrospective analyses of LAGEOS ranging results five or six years from now.

34. Site Plan: Fort Custer Air Force Station, Fort Custer, ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

34. Site Plan: Fort Custer Air Force Station, Fort Custer, Michigan, Modification of Electrical Distribution, General Site Plan, USACOE, no date. - Fort Custer Military Reservation, P-67 Radar Station, .25 mile north of Dickman Road, east of Clark Road, Battle Creek, Calhoun County, MI

47 CFR 74.537 - Temporary authorizations.

Code of Federal Regulations, 2011 CFR

2011-10-01

..., AUXILIARY, SPECIAL BROADCAST AND OTHER PROGRAM DISTRIBUTIONAL SERVICES Aural Broadcast Auxiliary Stations... STL or intercity relay station operation which cannot be conducted in accordance with § 74.24. Such... intercity relay station must be made in accordance with the procedures of § 1.931(b) of this chapter. (c...

47 CFR 74.537 - Temporary authorizations.

Code of Federal Regulations, 2013 CFR

2013-10-01

..., AUXILIARY, SPECIAL BROADCAST AND OTHER PROGRAM DISTRIBUTIONAL SERVICES Aural Broadcast Auxiliary Stations... STL or intercity relay station operation which cannot be conducted in accordance with § 74.24. Such... intercity relay station must be made in accordance with the procedures of § 1.931(b) of this chapter. (c...

47 CFR 74.537 - Temporary authorizations.

Code of Federal Regulations, 2014 CFR

2014-10-01

..., AUXILIARY, SPECIAL BROADCAST AND OTHER PROGRAM DISTRIBUTIONAL SERVICES Aural Broadcast Auxiliary Stations... STL or intercity relay station operation which cannot be conducted in accordance with § 74.24. Such... intercity relay station must be made in accordance with the procedures of § 1.931(b) of this chapter. (c...

47 CFR 74.1263 - Time of operation.

Code of Federal Regulations, 2010 CFR

2010-10-01

..., AUXILIARY, SPECIAL BROADCAST AND OTHER PROGRAM DISTRIBUTIONAL SERVICES FM Broadcast Translator Stations and FM Broadcast Booster Stations § 74.1263 Time of operation. (a) The licensee of an FM translator or... an FM translator or booster station is expected to provide a dependable service to the extent that...

47 CFR 74.1281 - Station records.

Code of Federal Regulations, 2010 CFR

2010-10-01

..., AUXILIARY, SPECIAL BROADCAST AND OTHER PROGRAM DISTRIBUTIONAL SERVICES FM Broadcast Translator Stations and..., place of business, or other suitable place, in one of the communities of license of the translator or booster, except that the station records of a booster or translator licensed to the licensee of the...

U.S. Geological Survey Catskill/Delaware Water-Quality Network: Water-Quality Report Water Year 2006

USGS Publications Warehouse

McHale, Michael R.; Siemion, Jason

2010-01-01

The U.S. Geological Survey operates a 60-station streamgaging network in the New York City Catskill/Delaware Water Supply System. Water-quality samples were collected at 13 of the stations in the Catskill/Delaware streamgaging network to provide resource managers with water-quality and water-quantity data from the water-supply system that supplies about 85 percent of the water needed by the more than 9 million residents of New York City. This report summarizes water-quality data collected at those 13 stations plus one additional station operated as a part of the U.S. Environmental Protection Agency's Regional Long-Term Monitoring Network for the 2006 water year (October 1, 2005 to September 30, 2006). An average of 62 water-quality samples were collected at each station during the 2006 water year, including grab samples collected every other week and storm samples collected with automated samplers. On average, 8 storms were sampled at each station during the 2006 water year. The 2006 calendar year was the second warmest on record and the summer of 2006 was the wettest on record for the northeastern United States. A large storm on June 26-28, 2006, caused extensive flooding in the western part of the network where record peak flows were measured at several watersheds.

Annual radiological environmental operating report, Browns Ferry Nuclear Plant, 1991

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

1992-04-01

This report describes the environmental radiological monitoring program conducted by TVA in the vicinity of Browns Ferry Nuclear Plant in 1991. The program includes the collection of samples from the environment and the determination of the concentrations of radioactive materials in the samples. Samples are taken from stations in the general area of the plant and from areas not influenced by plant operations. Station locations are selected after careful consideration of the weather patterns and projected radiation doses to the various areas around the plant. Material sampled includes air, water, milk, foods, vegetation, soil, fish, sediment, and direct radiation levels.more » Results from stations near the plant are compared with concentrations from control stations and with preoperational measurements to determine potential impacts of plant operations.« less

Mapping snow depth return levels: smooth spatial modeling versus station interpolation

NASA Astrophysics Data System (ADS)

Blanchet, J.; Lehning, M.

2010-12-01

For adequate risk management in mountainous countries, hazard maps for extreme snow events are needed. This requires the computation of spatial estimates of return levels. In this article we use recent developments in extreme value theory and compare two main approaches for mapping snow depth return levels from in situ measurements. The first one is based on the spatial interpolation of pointwise extremal distributions (the so-called Generalized Extreme Value distribution, GEV henceforth) computed at station locations. The second one is new and based on the direct estimation of a spatially smooth GEV distribution with the joint use of all stations. We compare and validate the different approaches for modeling annual maximum snow depth measured at 100 sites in Switzerland during winters 1965-1966 to 2007-2008. The results show a better performance of the smooth GEV distribution fitting, in particular where the station network is sparser. Smooth return level maps can be computed from the fitted model without any further interpolation. Their regional variability can be revealed by removing the altitudinal dependent covariates in the model. We show how return levels and their regional variability are linked to the main climatological patterns of Switzerland.

Automation in the Space Station module power management and distribution Breadboard

NASA Technical Reports Server (NTRS)

Walls, Bryan; Lollar, Louis F.

1990-01-01

The Space Station Module Power Management and Distribution (SSM/PMAD) Breadboard, located at NASA's Marshall Space Flight Center (MSFC) in Huntsville, Alabama, models the power distribution within a Space Station Freedom Habitation or Laboratory module. Originally designed for 20 kHz ac power, the system is now being converted to high voltage dc power with power levels on a par with those expected for a space station module. In addition to the power distribution hardware, the system includes computer control through a hierarchy of processes. The lowest level process consists of fast, simple (from a computing standpoint) switchgear, capable of quickly safing the system. The next level consists of local load center processors called Lowest Level Processors (LLP's). These LLP's execute load scheduling, perform redundant switching, and shed loads which use more than scheduled power. The level above the LLP's contains a Communication and Algorithmic Controller (CAC) which coordinates communications with the highest level. Finally, at this highest level, three cooperating Artificial Intelligence (AI) systems manage load prioritization, load scheduling, load shedding, and fault recovery and management. The system provides an excellent venue for developing and examining advanced automation techniques. The current system and the plans for its future are examined.

A comparative study of auroral morphology distribution between the Northern and Southern Hemisphere based on automatic classification

NASA Astrophysics Data System (ADS)

Yang, Qiuju; Hu, Ze-Jun

2018-03-01

Aurora is a very important geophysical phenomenon in the high latitudes of Arctic and Antarctic regions, and it is important to make a comparative study of the auroral morphology between the two hemispheres. Based on the morphological characteristics of the four labeled dayside discrete auroral types (auroral arc, drapery corona, radial corona and hot-spot aurora) on the 8001 dayside auroral images at the Chinese Arctic Yellow River Station in 2003, and by extracting the local binary pattern (LBP) features and using a k-nearest classifier, this paper performs an automatic classification of the 65 361 auroral images of the Chinese Arctic Yellow River Station during 2004-2009 and the 39 335 auroral images of the South Pole Station between 2003 and 2005. Finally, it obtains the occurrence distribution of the dayside auroral morphology in the Northern and Southern Hemisphere. The statistical results indicate that the four dayside discrete auroral types present a similar occurrence distribution between the two stations. To the best of our knowledge, we are the first to report statistical comparative results of dayside auroral morphology distribution between the Northern and Southern Hemisphere.

Pacific island landbird monitoring annual report, National Park of American Samoa, Ta‘u and Tutuila units, 2011

USGS Publications Warehouse

Judge, Seth W.; Camp, Richard J.; Vaivai, Visa; Hart, Patrick J.

2013-01-01

NPSA canopy and understory composition was predominantly native, and trees formed a dense closed canopy at nearly 90% of the stations sampled. More than half of the tree heights in both units were taller than 5 m and the majority of slopes were steeper than 20 degrees. There were no clear dominant tree species in the mixed native forests. The most common tree species documented included Syzygium spp., Dysoxylum spp., Ficus spp., Hibiscus tiliaceus and Rhus taitensis (among others). There were significant differences in the distribution of bird densities between legacy and random transects. Determining differences in detection probabilities cannot be definitively assessed from a single survey. We recommend both panels be sampled in the future until bias in density and abundance can be evaluated, or if sampling may be reduced.

Effective Discharge and Annual Sediment Yield on Brazos River

NASA Astrophysics Data System (ADS)

Rouhnia, M.; Salehi, M.; Keyvani, A.; Ma, F.; Strom, K. B.; Raphelt, N.

2012-12-01

Geometry of an alluvial river alters dynamically over the time due to the sediment mobilization on the banks and bottom of the river channel in various flow rates. Many researchers tried to define a single representative discharge for these morphological processes such as "bank-full discharge", "effective discharge" and "channel forming discharge". Effective discharge is the flow rate in which, the most sediment load is being carried by water, in a long term period. This project is aimed to develop effective discharge estimates for six gaging stations along the Brazos River from Waco, TX to Rosharon, TX. The project was performed with cooperation of the In-stream Flow Team of the Texas Water Development Board (TWDB). Project objectives are listed as: 1) developing "Flow Duration Curves" for six stations based on mean-daily discharge by downloading the required, additional data from U.S Geological Survey website, 2) developing "Rating Curves" for six gaging stations after sampling and field measurements in three different flow conditions, 3) developing a smooth shaped "Sediment Yield Histogram" with a well distinguished peak as effective discharge. The effective discharge was calculated using two methods of manually and automatic bin selection. The automatic method is based on kernel density approximation. Cross-sectional geometry measurements, particle size distributions and water field samples were processed in the laboratory to obtain the suspended sediment concentration associated with flow rate. Rating curves showed acceptable trends, as the greater flow rate we experienced, the more sediment were carried by water.

Correlation of forebody pressures and aircraft yawing moments on the X-29A aircraft at high angles of attack

NASA Technical Reports Server (NTRS)

Fisher, David F.; Richwine, David M.; Landers, Stephen

1992-01-01

In-flight pressure distributions at four fuselage stations on the forebody of the X-29A aircraft have been reported at angles of attack from 15 to 66 deg and at Mach numbers from 0.22 to 0.60. At angles of attack of 20 deg and higher, vortices shed from the nose strake caused suction peaks in the pressure distributions that generally increased in magnitude with angle of attack. Above 30 deg-angle of attack, the forebody pressure distributions became asymmetrical at the most forward station, while they remained nearly symmetrical until 50 to 55 deg-angle of attack for the aft stations. Between 59 to 66 deg-angle of attack, the asymmetry of the pressure distributions changed direction. Yawing moments for the forebody alone were obtained by integrating the forebody pressure distributions. At 45 deg-angle of attack, the aircraft yaws to the right and at 50 deg and higher, the aircraft yaws to the left. The forebody yawing moments correlated well with the aircraft left yawing moment at an angle of attack of 50 deg or higher. At a 45 deg-angle of attack, the forebody yawing moments did not correlate well with the aircraft yawing moment, but it is suggested that this was due to asymmetric pressures on the cockpit region of the fuselage which was not instrumented. The forebody was also shown to provide a positive component of directional stability of the aircraft at angles of attack of 25 deg or higher. A Mach number effect was noted at angles of attack of 30 deg or higher at the station where the nose strake was present. At this station, the suction peaks in the pressure distributions at the highest Mach number were reduced and much more symmetrical as compared to the lower Mach number pressure distributions.

A comparison of two sampling designs for fish assemblage assessment in a large river

USGS Publications Warehouse

Kiraly, Ian A.; Coghlan, Stephen M.; Zydlewski, Joseph D.; Hayes, Daniel

2014-01-01

We compared the efficiency of stratified random and fixed-station sampling designs to characterize fish assemblages in anticipation of dam removal on the Penobscot River, the largest river in Maine. We used boat electrofishing methods in both sampling designs. Multiple 500-m transects were selected randomly and electrofished in each of nine strata within the stratified random sampling design. Within the fixed-station design, up to 11 transects (1,000 m) were electrofished, all of which had been sampled previously. In total, 88 km of shoreline were electrofished during summer and fall in 2010 and 2011, and 45,874 individuals of 34 fish species were captured. Species-accumulation and dissimilarity curve analyses indicated that all sampling effort, other than fall 2011 under the fixed-station design, provided repeatable estimates of total species richness and proportional abundances. Overall, our sampling designs were similar in precision and efficiency for sampling fish assemblages. The fixed-station design was negatively biased for estimating the abundance of species such as Common Shiner Luxilus cornutus and Fallfish Semotilus corporalis and was positively biased for estimating biomass for species such as White Sucker Catostomus commersonii and Atlantic Salmon Salmo salar. However, we found no significant differences between the designs for proportional catch and biomass per unit effort, except in fall 2011. The difference observed in fall 2011 was due to limitations on the number and location of fixed sites that could be sampled, rather than an inherent bias within the design. Given the results from sampling in the Penobscot River, application of the stratified random design is preferable to the fixed-station design due to less potential for bias caused by varying sampling effort, such as what occurred in the fall 2011 fixed-station sample or due to purposeful site selection.

The Danish Greenland Magnetometer Chain - Status and Outlook

NASA Astrophysics Data System (ADS)

Behlke, R.

2016-12-01

DTU Space operates the Greenland magnetometer array, including 19 variometer stations whereof 3 are geomagnetic observatories. This array consists of a West Coast Chain with 13 stations including three observatories between 77.47 and 61.16 geographic North. On the East Coast 5 variometer stations are located between 81.6 and 65.6 geographic North. The Greenland Array covers polar cap, cusp and auroral regions. These data allow the monitoring of electromagnetic processes in the polar ionosphere and magnetosphere, and are a significant contribution to global data sets. The vast majority of the sensors now employed are the Danish FGE 3-axis linear-core fluxgate magnetometers designed and built under the supervision of Ole Rasmussen and later Lars William Pedersen. They are optimized for long-term stability (observatory-quality instruments) rather than high sensitivity. The stations use 16 bit A/D converters with 20s or 1s sampling rate, optimized for 1 minute mean data. Hence, the rms-noise is approximately 0.1 nT in the 1 mHz - 1 Hz band, the time accuracy is 1s and the final resolution is 0.25 nT for most data at 20s sampling rate and 0.125 nT for most data at 1s sampling rate. During setup, the sensor axes are oriented along local magnetic north (H), local magnetic east (E) and vertical down (Z). Sensors at some stations are equipped with a suspension which guarantees vertical alignment. The instruments run fully automatically and require (normally) no manual intervention. All stations use the FGE vector magnetometer. Greenland magnetometer data has been aquired in digital form since 1981. From 1981 through 1990 all stations recorded with 1-min sampling rate. In 1986 the acquisition systems was gradually modified in order to record with 20-s sampling rate. Modification was completed by 1991, and since then all stations run at 20-s sampling rate. In 1999 acquisition system was made capable to record at 1-s sampling in addition to the continued 20-s sampoling rate. In 2001 most stations were upgraded, and in the summer of 2002 the upgrade was completed. Now all stations have laptops as dataloggers recording at 1Hz. In this presentation, we provide a status overview of the chain and its role within the G-ESC.

Space Station Environmental Control/Life Support System engineering

NASA Technical Reports Server (NTRS)

Miller, C. W.; Heppner, D. B.

1985-01-01

The present paper is concerned with a systems engineering study which has provided an understanding of the overall Space Station ECLSS (Environmental Control and Life Support System). ECLSS/functional partitioning is considered along with function criticality, technology alternatives, a technology description, single thread systems, Space Station architectures, ECLSS distribution, mechanical schematics per space station, and Space Station ECLSS characteristics. Attention is given to trade studies and system synergism. The Space Station functional description had been defined by NASA. The ECLSS will utilize technologies which embody regenerative concepts to minimize the use of expendables.

On precipitation monitoring with theoretical statistical distributions

NASA Astrophysics Data System (ADS)

Cindrić, Ksenija; Juras, Josip; Pasarić, Zoran

2018-04-01

A common practice in meteorological drought monitoring is to transform the observed precipitation amounts to the standardised precipitation index (SPI). Though the gamma distribution is usually employed for this purpose, some other distribution may be used, particularly in regions where zero precipitation amounts are recorded frequently. In this study, two distributions are considered alongside with the gamma distribution: the compound Poisson exponential distribution (CPE) and the square root normal distribution (SRN). They are fitted to monthly precipitation amounts measured at 24 stations in Croatia in the 55-year-long period (1961-2015). At five stations, long-term series (1901-2015) are available and they have been used for a more detailed investigation. The accommodation of the theoretical distributions to empirical ones is tested by comparison of the corresponding empirical and theoretical ratios of the skewness and the coefficient of variation. Furthermore, following the common approach to precipitation monitoring (CLIMAT reports), the comparison of the empirical and theoretical quintiles in the two periods (1961-1990 and 1991-2015) is examined. The results from the present study reveal that it would be more appropriate to implement theoretical distributions in such climate reports, since they provide better evaluation for monitoring purposes than the current empirical distribution. Nevertheless, deciding on an optimal theoretical distribution for different climate regimes and for different time periods is not easy to accomplish. With regard to Croatian stations (covering different climate regimes), the CPE or SRN distribution could also be the right choice in the climatological practice, in addition to the gamma distribution.

Research on florfenicol residue in coastal area of dalian (northern china) and analysis of functional diversity of the microbial community in marine sediment.

PubMed

Zong, Humin; Ma, Deyi; Wang, Juying; Hu, Jiangtao

2010-02-01

An analytical method based on high performance liquid chromatography tandem mass spectrometry (HPLC-MS/MS) has been developed to investigate florfenicol residues. Among 11 stations, florfenicol was detected in six water samples. The concentrations of florfenicol in the six samples were 64.2 microg L(-1), 390.6 microg L(-1), 1.1 x 10(4) microg L(-1), 29.8 microg L(-1), 61.6 microg L(-1), 34.9 microg L(-1), respectively. These results showed that high levels of florfenicol were observed in water samples collected from stations influenced by aquaculture discharges. However, no florfenicol residue was detected in the sediment samples. Furthermore, the functional diversities of microbial community in four marine sediment samples were analyzed by Biolog microplate. For the sediment samples from the stations where antibacterials had been used, the functional diversity of microbial community was much lower than those from the stations where antibacterials were not used.

A Bayesian approach to earthquake source studies

NASA Astrophysics Data System (ADS)

Minson, Sarah

Bayesian sampling has several advantages over conventional optimization approaches to solving inverse problems. It produces the distribution of all possible models sampled proportionally to how much each model is consistent with the data and the specified prior information, and thus images the entire solution space, revealing the uncertainties and trade-offs in the model. Bayesian sampling is applicable to both linear and non-linear modeling, and the values of the model parameters being sampled can be constrained based on the physics of the process being studied and do not have to be regularized. However, these methods are computationally challenging for high-dimensional problems. Until now the computational expense of Bayesian sampling has been too great for it to be practicable for most geophysical problems. I present a new parallel sampling algorithm called CATMIP for Cascading Adaptive Tempered Metropolis In Parallel. This technique, based on Transitional Markov chain Monte Carlo, makes it possible to sample distributions in many hundreds of dimensions, if the forward model is fast, or to sample computationally expensive forward models in smaller numbers of dimensions. The design of the algorithm is independent of the model being sampled, so CATMIP can be applied to many areas of research. I use CATMIP to produce a finite fault source model for the 2007 Mw 7.7 Tocopilla, Chile earthquake. Surface displacements from the earthquake were recorded by six interferograms and twelve local high-rate GPS stations. Because of the wealth of near-fault data, the source process is well-constrained. I find that the near-field high-rate GPS data have significant resolving power above and beyond the slip distribution determined from static displacements. The location and magnitude of the maximum displacement are resolved. The rupture almost certainly propagated at sub-shear velocities. The full posterior distribution can be used not only to calculate source parameters but also to determine their uncertainties. So while kinematic source modeling and the estimation of source parameters is not new, with CATMIP I am able to use Bayesian sampling to determine which parts of the source process are well-constrained and which are not.

Space station automation of common module power management and distribution

NASA Technical Reports Server (NTRS)

Miller, W.; Jones, E.; Ashworth, B.; Riedesel, J.; Myers, C.; Freeman, K.; Steele, D.; Palmer, R.; Walsh, R.; Gohring, J.

1989-01-01

The purpose is to automate a breadboard level Power Management and Distribution (PMAD) system which possesses many functional characteristics of a specified Space Station power system. The automation system was built upon 20 kHz ac source with redundancy of the power buses. There are two power distribution control units which furnish power to six load centers which in turn enable load circuits based upon a system generated schedule. The progress in building this specified autonomous system is described. Automation of Space Station Module PMAD was accomplished by segmenting the complete task in the following four independent tasks: (1) develop a detailed approach for PMAD automation; (2) define the software and hardware elements of automation; (3) develop the automation system for the PMAD breadboard; and (4) select an appropriate host processing environment.

Analysis of surface-water data network in Kansas for effectiveness in providing regional streamflow information; with a section on theory and application of generalized least squares

USGS Publications Warehouse

Medina, K.D.; Tasker, Gary D.

1987-01-01

This report documents the results of an analysis of the surface-water data network in Kansas for its effectiveness in providing regional streamflow information. The network was analyzed using generalized least squares regression. The correlation and time-sampling error of the streamflow characteristic are considered in the generalized least squares method. Unregulated medium-, low-, and high-flow characteristics were selected to be representative of the regional information that can be obtained from streamflow-gaging-station records for use in evaluating the effectiveness of continuing the present network stations, discontinuing some stations, and (or) adding new stations. The analysis used streamflow records for all currently operated stations that were not affected by regulation and for discontinued stations for which unregulated flow characteristics, as well as physical and climatic characteristics, were available. The State was divided into three network areas, western, northeastern, and southeastern Kansas, and analysis was made for the three streamflow characteristics in each area, using three planning horizons. The analysis showed that the maximum reduction of sampling mean-square error for each cost level could be obtained by adding new stations and discontinuing some current network stations. Large reductions in sampling mean-square error for low-flow information could be achieved in all three network areas, the reduction in western Kansas being the most dramatic. The addition of new stations would be most beneficial for mean-flow information in western Kansas. The reduction of sampling mean-square error for high-flow information would benefit most from the addition of new stations in western Kansas. Southeastern Kansas showed the smallest error reduction in high-flow information. A comparison among all three network areas indicated that funding resources could be most effectively used by discontinuing more stations in northeastern and southeastern Kansas and establishing more new stations in western Kansas.

Analysis of surface-water data network in Kansas for effectiveness in providing regional streamflow information

USGS Publications Warehouse

Medina, K.D.; Tasker, Gary D.

1985-01-01

The surface water data network in Kansas was analyzed using generalized least squares regression for its effectiveness in providing regional streamflow information. The correlation and time-sampling error of the streamflow characteristic are considered in the generalized least squares method. Unregulated medium-flow, low-flow and high-flow characteristics were selected to be representative of the regional information that can be obtained from streamflow gaging station records for use in evaluating the effectiveness of continuing the present network stations, discontinuing some stations; and/or adding new stations. The analysis used streamflow records for all currently operated stations that were not affected by regulation and discontinued stations for which unregulated flow characteristics , as well as physical and climatic characteristics, were available. The state was divided into three network areas, western, northeastern, and southeastern Kansas, and analysis was made for three streamflow characteristics in each area, using three planning horizons. The analysis showed that the maximum reduction of sampling mean square error for each cost level could be obtained by adding new stations and discontinuing some of the present network stations. Large reductions in sampling mean square error for low-flow information could be accomplished in all three network areas, with western Kansas having the most dramatic reduction. The addition of new stations would be most beneficial for man- flow information in western Kansas, and to lesser degrees in the other two areas. The reduction of sampling mean square error for high-flow information would benefit most from the addition of new stations in western Kansas, and the effect diminishes to lesser degrees in the other two areas. Southeastern Kansas showed the smallest error reduction in high-flow information. A comparison among all three network areas indicated that funding resources could be most effectively used by discontinuing more stations in northeastern and southeastern Kansas and establishing more new stations in western Kansas. (Author 's abstract)

Biological field stations: research legacies and sites for serendipity

Treesearch

William K. Michener; Keith L. Bildstein; Arthur McKee; Robert R. Parmenter; William W. Hargrove; Deedra McClearn; Mark Stromberg

2009-01-01

Biological field stations are distributed throughout North America, capturing much of the ecological variability present at the continental scale and encompassing many unique habitats. In addition to their role in supporting research and education, field stations offer legacies of data, specimens, and accumulated knowledge. Such legacies often provide the only...

47 CFR 74.781 - Station records.

Code of Federal Regulations, 2010 CFR

2010-10-01

..., AUXILIARY, SPECIAL BROADCAST AND OTHER PROGRAM DISTRIBUTIONAL SERVICES Low Power TV, TV Translator, and TV Booster Stations § 74.781 Station records. (a) The licensee of a low power TV, TV translator, or TV... other suitable place, in one of the communities of license of the translator or booster, except that the...

47 CFR 74.1283 - Station identification.

Code of Federal Regulations, 2010 CFR

2010-10-01

..., AUXILIARY, SPECIAL BROADCAST AND OTHER PROGRAM DISTRIBUTIONAL SERVICES FM Broadcast Translator Stations and... translator station will consist of the initial letter K or W followed by the channel number assigned to the translator and two letters. The use of the initial letter will generally conform to the pattern used in the...

47 CFR 74.789 - Broadcast regulations applicable to digital low power television and television translator stations.

Code of Federal Regulations, 2010 CFR

2010-10-01

... power television and television translator stations. 74.789 Section 74.789 Telecommunication FEDERAL... AND OTHER PROGRAM DISTRIBUTIONAL SERVICES Low Power TV, TV Translator, and TV Booster Stations § 74.789 Broadcast regulations applicable to digital low power television and television translator...

Inert gases in Sea of Fertility regolith

NASA Technical Reports Server (NTRS)

Vinogradov, A. P.; Zadorozhnyy, I. K.

1974-01-01

The content and isotopic composition were studied of inert gases -- He, Ne, Ar, Kr, and Xe -- in samples of lunar regolith returned by the Luna 16 automatic station. The samples were taken from depths of about 12 and 30 cm. The high concentrations of inert gases exceed by several orders their concentrations observed in ordinary stony meteorites. The gases in lunar regolith were a complex mixture of gases of different origins: Solar, cosmogenic, radiogenic, and so on. Solar wind gases predominated, distributed in the thin surficial layer of the regolith grains. The concentrations of these gases in the surficial layer is several cubic centimeters per gram. The isotopic composition of the inert gases of solar origin approaches their composition measured in gas-rich meteorites.

[Distribution of diatoms in central city of Beijing].

PubMed

Li, Li-Ping; Sun, Ting-Yi; Liu, Hong-Xia; Zhang, Hai-Dong; Bai, Ying-Jie; Wang, Rong-Shuai; Liu, Liang

2012-08-01

To explore the quantity and distribution of diatoms in main rivers and lakes in Xicheng, Dongcheng, Chaoyang, Haidian, Fengtai and Shijingshan Districts of the city of Beijing. Water samples were examined through the method of disorganizing, which were collected from 16 rivers and lakes in the central city of Beijing in September and October 2011. Diatom species and proportions of water samples were analyzed using DotSlide microscope station. A total of 10 species of diatoms were detected. Cyclotella, Synedra and Melosira etc. were found to be the dominant species via quantitative analysis. Significant differences were observed for diatom species and proportions among the different rivers and lakes. Melosira was found to be the dominant species in the Chang River; Synedra, in the Zhuan River, the Kunyu River and the Taoranting Park; Cyclotella, in the East Moat River, the Ba River, the Liangshui River and the Yongding River; and Navicula, in the Liangma River; Nitzschia, in the diversion canal of the Yongding River. The features of distribution of diatoms in the central city of Beijing are outlined. The morphological and relative constituent ratio database of diatoms are established in central city of Beijing.

Quantification of Uncertainty in the Flood Frequency Analysis

NASA Astrophysics Data System (ADS)

Kasiapillai Sudalaimuthu, K.; He, J.; Swami, D.

2017-12-01

Flood frequency analysis (FFA) is usually carried out for planning and designing of water resources and hydraulic structures. Owing to the existence of variability in sample representation, selection of distribution and estimation of distribution parameters, the estimation of flood quantile has been always uncertain. Hence, suitable approaches must be developed to quantify the uncertainty in the form of prediction interval as an alternate to deterministic approach. The developed framework in the present study to include uncertainty in the FFA discusses a multi-objective optimization approach to construct the prediction interval using ensemble of flood quantile. Through this approach, an optimal variability of distribution parameters is identified to carry out FFA. To demonstrate the proposed approach, annual maximum flow data from two gauge stations (Bow river at Calgary and Banff, Canada) are used. The major focus of the present study was to evaluate the changes in magnitude of flood quantiles due to the recent extreme flood event occurred during the year 2013. In addition, the efficacy of the proposed method was further verified using standard bootstrap based sampling approaches and found that the proposed method is reliable in modeling extreme floods as compared to the bootstrap methods.

Living on the edge: Distribution of Dungeness crab Cancer magister in a recently deglaciated fjord

USGS Publications Warehouse

Taggart, S. James; Hooge, P.N.; Mondragon, Jennifer; Hooge, Elizabeth Ross; Andrews, A.G.

2003-01-01

Glacier Bay, Alaska, has supported a productive Dungeness crab fishery, although the area where the fishery occurred was small relative to the remainder of the Bay. We hypothesized that 1 or more abiotic limiting factors prevented crabs from surviving in the upper Bay. We tested this hypothesis by systematically sampling for relative abundance of Dungeness crabs from the mouth to the head of the Bay. We measured salinity, temperature and turbidity at each of the sampling sites and at permanent stations to characterize the habitat within and among years. We expected to find a completely truncated spatial distribution. Instead, we found that adult Dungeness crabs can survive in habitats heavily influenced by tidewater glaciers. There were significantly fewer crabs in the upper Bay and a sharp decrease in abundance around 40 km from the mouth of the Bay. The region of the Bay beyond 40 km from the mouth had a very low density of predominately adult male crabs. The narrow size frequency distribution and the lack of small crabs is consistent with poor survival in one of the pre-adult life stages in the upper Bay.

Sulfur and Oxygen Isotopic Composition of Sulfate in the Fresh Water, King Sejong Station, King George Island, Antarctica

NASA Astrophysics Data System (ADS)

Kim, M.; Lee, I.; Lee, J.; Park, B.; Mayer, B.; Kaufman, A. J.; Park, S.; Kim, G.; Lee, K.

2008-12-01

Isotopic compositions of sulfur (δ34S) and oxygen (δ18O) were measured for the sulfate of the fresh water near the King Sejong Station, King George Island, Antarctica. Sejong station is located in the Barton peninsular of the King George Island. The geology around King Sejong station mainly composed of basalt-andesite, quart monzodiorite, and granodiorite. Lapilli tuff, conglomerate, sandstone, and siltstone occur along the southern and eastern shore of the Barton peninsula. Lapilli tuff also occurs on the highland located on southeastern part of the Barton peninsula. The δ34S values of sulfate extracted from fresh water samples at King Sejong Station range from 13.7 to 16.3 per mil excluding 1 sample. These sulfur values are very narrow in their range compared with those from anthropogenic sources. These sulfur values are 5 to 7 per mil lower than those of typical present seawater. Considering the rocks occurring near the King Sejong station, these sulfur isotopic values do not seem to be related to any evaporites of certain age. In Antarctic region the natural source of sulfate dissolved in water could be originated from marine biogenic source (DMS), sea-salt, volcanic source, or other continental sources. Most of the δ34S values of sulfate at King Sejong station seems to indicate the dominance of marine biogenic origin for the source of sulfur. The δ18O values of sulfate extracted from fresh water samples at King Sejong Station range from 1.9 to 6.4 per mil excluding 1 sample. These oxygen isotope values are lower than those of the sulfate in the present seawater by 6 per mil. However, both sulfur and oxygen isotope values strongly represent the influence of the seawater sulfate. One sample have 2.6 and -1.1 per mil in its δ34S and δ18O values, respectively, that are quite different from the isotopic values of other samples. This sample was collected in the highland far from the King Sejong station. Therefore this sample might reflect the composition of rather pure precipitation not affected by seawater sulfate. The atmospheric deposition might have been the major source of dissolved sulfate but it is not clear whether the source materials are from natural and/or anthropogenic origin.

Water Resources Data North Dakota Water Year 2002 Volume 1. Surface Water

USGS Publications Warehouse

Harkness, R.E.; Lundgren, R.F.; Norbeck, S.W.; Robinson, S.M.; Sether, B.A.

2003-01-01

Water-resources data for the 2002 water year for North Dakota consists of records of discharge, stage, and water quality for streams; contents, stage, and water quality for lakes and reservoirs; and water levels and water quality for ground-water wells. Volume 1 contains records of water discharge for 106 streamflow-gaging stations; stage only for 22 river-stage stations; contents and/or stage for 14 lake or reservoir stations; annual maximum discharge for 35 crest-stage stations; and water-quality for 96 streamflow-gaging stations, 3 river-stage stations, 11 lake or reservoir stations, 8 miscellaneous sample sites on rivers, and 63 miscellaneous sample sites on lakes and wetlands. Data are included for 7 water-quality monitor sites on streams and 2 precipitation-chemistry stations. These data represent that part of the National Water Data System operated by the U.S. Geological Survey and cooperating Federal, State, and local agencies in North Dakota.

Water Resources Data North Dakota Water Year 2003, Volume 1. Surface Water

USGS Publications Warehouse

Robinson, S.M.; Lundgren, R.F.; Sether, B.A.; Norbeck, S.W.; Lambrecht, J.M.

2004-01-01

Water-resources data for the 2003 water year for North Dakota consists of records of discharge, stage, and water quality for streams; contents, stage, and water quality for lakes and reservoirs; and water levels and water quality for ground-water wells. Volume 1 contains records of water discharge for 108 streamflow-gaging stations; stage only for 24 river-stage stations; contents and/or stage for 14 lake or reservoir stations; annual maximum discharge for 32 crest-stage stations; and water-quality for 99 streamflow-gaging stations, 5 river-stage stations, 11 lake or reservoir stations, 8 miscellaneous sample sites on rivers, and 63 miscellaneous sample sites on lakes and wetlands. Data are included for 7 water-quality monitor sites on streams and 2 precipitation-chemistry stations. These data represent that part of the National Water Data System operated by the U.S. Geological Survey and cooperating Federal, State, and local agencies in North Dakota.

Water Resources Data North Dakota Water Year 2001, Volume 1. Surface Water

USGS Publications Warehouse

Harkness, R.E.; Berkas, W.R.; Norbeck, S.W.; Robinson, S.M.

2002-01-01

Water-resources data for the 2001 water year for North Dakota consists of records of discharge, stage, and water quality for streams; contents, stage, and water quality for lakes and reservoirs; and water levels and water quality for ground-water wells. Volume 1 contains records of water discharge for 103 streamflow-gaging stations; stage only for 20 river-stage stations; contents and/or stage for 13 lake or reservoir stations; annual maximum discharge for 35 crest-stage stations; and water-quality for 94 streamflow-gaging stations, 2 river-stage stations, 9 lake or reservoir stations, 7 miscellaneous sample sites on rivers, and 58 miscellaneous sample sites on lakes and wetlands. Data are included for 9 water-quality monitor sites on streams and 2 precipitation-chemistry stations. These data represent that part of the National Water Data System operated by the U.S. Geological Survey and cooperating Federal, State, and local agencies in North Dakota.

Uncertainties in models of tropospheric ozone based on Monte Carlo analysis: Tropospheric ozone burdens, atmospheric lifetimes and surface distributions

NASA Astrophysics Data System (ADS)

Derwent, Richard G.; Parrish, David D.; Galbally, Ian E.; Stevenson, David S.; Doherty, Ruth M.; Naik, Vaishali; Young, Paul J.

2018-05-01

Recognising that global tropospheric ozone models have many uncertain input parameters, an attempt has been made to employ Monte Carlo sampling to quantify the uncertainties in model output that arise from global tropospheric ozone precursor emissions and from ozone production and destruction in a global Lagrangian chemistry-transport model. Ninety eight quasi-randomly Monte Carlo sampled model runs were completed and the uncertainties were quantified in tropospheric burdens and lifetimes of ozone, carbon monoxide and methane, together with the surface distribution and seasonal cycle in ozone. The results have shown a satisfactory degree of convergence and provide a first estimate of the likely uncertainties in tropospheric ozone model outputs. There are likely to be diminishing returns in carrying out many more Monte Carlo runs in order to refine further these outputs. Uncertainties due to model formulation were separately addressed using the results from 14 Atmospheric Chemistry Coupled Climate Model Intercomparison Project (ACCMIP) chemistry-climate models. The 95% confidence ranges surrounding the ACCMIP model burdens and lifetimes for ozone, carbon monoxide and methane were somewhat smaller than for the Monte Carlo estimates. This reflected the situation where the ACCMIP models used harmonised emissions data and differed only in their meteorological data and model formulations whereas a conscious effort was made to describe the uncertainties in the ozone precursor emissions and in the kinetic and photochemical data in the Monte Carlo runs. Attention was focussed on the model predictions of the ozone seasonal cycles at three marine boundary layer stations: Mace Head, Ireland, Trinidad Head, California and Cape Grim, Tasmania. Despite comprehensively addressing the uncertainties due to global emissions and ozone sources and sinks, none of the Monte Carlo runs were able to generate seasonal cycles that matched the observations at all three MBL stations. Although the observed seasonal cycles were found to fall within the confidence limits of the ACCMIP members, this was because the model seasonal cycles spanned extremely wide ranges and there was no single ACCMIP member that performed best for each station. Further work is required to examine the parameterisation of convective mixing in the models to see if this erodes the isolation of the marine boundary layer from the free troposphere and thus hides the models' real ability to reproduce ozone seasonal cycles over marine stations.

National Aeronautics and Space Administration Biological Specimen Repository

NASA Technical Reports Server (NTRS)

McMonigal, Kathleen A.; Pietrzyk, Robert a.; Johnson, Mary Anne

2008-01-01

The National Aeronautics and Space Administration Biological Specimen Repository (Repository) is a storage bank that is used to maintain biological specimens over extended periods of time and under well-controlled conditions. Samples from the International Space Station (ISS), including blood and urine, will be collected, processed and archived during the preflight, inflight and postflight phases of ISS missions. This investigation has been developed to archive biosamples for use as a resource for future space flight related research. The International Space Station (ISS) provides a platform to investigate the effects of microgravity on human physiology prior to lunar and exploration class missions. The storage of crewmember samples from many different ISS flights in a single repository will be a valuable resource with which researchers can study space flight related changes and investigate physiological markers. The development of the National Aeronautics and Space Administration Biological Specimen Repository will allow for the collection, processing, storage, maintenance, and ethical distribution of biosamples to meet goals of scientific and programmatic relevance to the space program. Archiving of the biosamples will provide future research opportunities including investigating patterns of physiological changes, analysis of components unknown at this time or analyses performed by new methodologies.

The Amoco CadizOil Spill: Evolution of Petroleum Hydrocarbons in the Ile Grande Salt Marshes (Brittany) after a 13-year Period

NASA Astrophysics Data System (ADS)

Mille, G.; Munoz, D.; Jacquot, F.; Rivet, L.; Bertrand, J.-C.

1998-11-01

The Ile Grande salt marshes (Brittany coast) were polluted by petroleum hydrocarbons after theAmoco Cadizgrounding in 1978. Thirteen years after the oil spill, sediments were analysed for residual hydrocarbons in order to monitor the aliphatic and aromatic hydrocarbon signatures and to assess both qualitatively and quantitatively the changes in composition of theAmoco Cadizoil. Six stations were selected in the Ile Grande salt marshes and sediments were sampled to a depth of 20 cm. For each sample, the hydrocarbon compositions were determined for alkanes, alkenes, aromatics and biomarkers (terpanes, steranes, diasteranes). Hydrocarbon levels drastically decreased between 1978 and 1991, but to different extents according to the initial degree of contamination. In 1991, hydrocarbon concentrations never exceeded 1·7 g kg-1sediment dry weight, and in most cases were less than 0·1 g kg-1sediment dry weight. Even though petroleum hydrocarbons are still present, natural hydrocarbons were also detected at several stations. Changes in some biomarker distributions were observed 13 years after the oil spill. Nevertheless, most of the biomarkers are very stable in the salt marsh environment and remain unaltered even after a 13-year period.

78 FR 45989 - Vogtle Electric Generating Station, Units 3 and 4; Southern Nuclear Operating Company; Change to...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-07-30

... Generating Station, Units 3 and 4; Southern Nuclear Operating Company; Change to the Primary Sampling System.... The amendment requests to modify the Primary Sampling System (PSS) design, including changes to Tier 1....13-1 ``Primary Sampling System,'' and Subsection 2.3.13, ``Primary Sampling System'' of the Updated...

78 FR 45987 - Vogtle Electric Generating Station, Units 3 and 4; Southern Nuclear Operating Company; Change to...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-07-30

... Generating Station, Units 3 and 4; Southern Nuclear Operating Company; Change to the Primary Sampling System.... The amendment requests to modify the Primary Sampling System (PSS) design, including changes to Tier 1....13-1 ``Primary Sampling System,'' and Subsection 2.3.13, ``Primary Sampling System'' of the Updated...

Using host-associated genetic markers to investigate sources of fecal contamination in two Vermont streams

USGS Publications Warehouse

Medalie, Laura; Matthews, Leslie J.; Stelzer, Erin A.

2011-01-01

The use of host-associated Bacteroidales-based 16S ribosomal ribonucleic acid genetic markers was investigated as a tool for providing information to managers on sources of bacterial impairment in Vermont streams. The study was conducted during 2009 in two watersheds on the U.S. Environmental Protection Agency's 303(d) List of Impaired Waters, the Huntington and the Mettawee Rivers. Streamwater samples collected during high-flow and base-flow conditions were analyzed for concentrations of Escherichia coli (E. coli) and Bacteroidales genetic markers (General AllBac, Human qHF183 and BacHum, Ruminant BoBac, and Canid BacCan) to identify humans, ruminants, and canids as likely or unlikely major sources of fecal contamination. Fecal reference samples from each of the potential source groups, as well as from common species of wildlife, were collected during the same season and from the same watersheds as water samples. The results were combined with data from other states to assess marker cross reaction and to relate marker results to E. coli, the regulated water-quality parameter, with a higher degree of statistical significance. Results from samples from the Huntington River collected under different flow conditions on three dates indicated that humans were unlikely to be a major source of fecal contamination, except for a single positive result at one station that indicated the potential for human sources. Ruminants (deer, moose, cow, or sheep) were potential sources of fecal contamination at all six stations on the Huntington River during one high-flow event and at all but two stations during the other high-flow event. Canids were potential sources of fecal contamination at some stations during two high-flow events, with genetic-marker concentrations in samples from two of the six stations showing consistent positive results for canids for both storm dates. A base-flow sample showed no evidence of major fecal contamination in the Huntington River from humans, ruminants, or canids. Results from samples from the Mettawee River watershed collected during high-flow conditions (12 storm samples on 2 dates at 6 stations) indicated that there was no evidence of fecal contamination from humans in seven samples and possible evidence in five samples. Results for humans were positive for only one station during both storm events. For two of the five samples with evidence for human fecal contamination, results for two different human genetic markers agreed, but results from three samples were inconsistent. In samples from five of the six Mettawee stations, ruminants were a potential source of fecal contamination on at least one of the three sampled dates, including three positive results for the base-flow sample. Yet samples from all of the stations that showed positive results for ruminants did so for only one or two of the three sampled dates. Samples from only one of the six stations gave consistent results, which were negative for ruminants for all three dates. In the Mettawee River base-flow sample, humans were an unlikely source of major fecal contamination. Factors that may influence results and conclusions include the timing of sample collection relative to the storm event; variability of E. coli and Bacteroidales concentrations in fecal reference samples and in water; sampling and analytical errors; the potential cross reactivity of host-associated genetic markers; and different persistence and survival rates of E. coli bacteria and Bacteroidales genetic markers on land, in water, and by season. These factors interfere with the ability to directly relate Bacteroidales concentrations to E. coli concentrations in river samples. It must be recognized that while use of Bacteroidales genetic markers as a source tracking tool coupled with the interpretive approach described in this report cannot be used quantitatively to pinpoint sources, it can be used to exclude potential sources as major contributors to fecal contamination.

UMTS Network Stations

NASA Astrophysics Data System (ADS)

Hernandez, C.

2010-09-01

The weakness of small island electrical grids implies a handicap for the electrical generation with renewable energy sources. With the intention of maximizing the installation of photovoltaic generators in the Canary Islands, arises the need to develop a solar forecasting system that allows knowing in advance the amount of PV generated electricity that will be going into the grid, from the installed PV power plants installed in the island. The forecasting tools need to get feedback from real weather data in "real time" from remote weather stations. Nevertheless, the transference of this data to the calculation computer servers is very complicated with the old point to point telecommunication systems that, neither allow the transfer of data from several remote weather stations simultaneously nor high frequency of sampling of weather parameters due to slowness of the connection. This one project has developed a telecommunications infrastructure that allows sensorizadas remote stations, to send data of its sensors, once every minute and simultaneously, to the calculation server running the solar forecasting numerical models. For it, the Canary Islands Institute of Technology has added a sophisticated communications network to its 30 weather stations measuring irradiation at strategic sites, areas with high penetration of photovoltaic generation or that have potential to host in the future photovoltaic power plants connected to the grid. In each one of the stations, irradiance and temperature measurement instruments have been installed, over inclined silicon cell, global radiation on horizontal surface and room temperature. Mobile telephone devices have been installed and programmed in each one of the weather stations, which allow the transfer of their data taking advantage of the UMTS service offered by the local telephone operator. Every minute the computer server running the numerical weather forecasting models receives data inputs from 120 instruments distributed over the 30 radiometric stations. As a the result, currently it exist a stable, flexible, safe and economic infrastructure of radiometric stations and telecommunications that allows, on the one hand, to have data in real time from all 30 remote weather stations, and on the other hand allows to communicate with them in order to reprogram them and to carry out maintenance works.

Surface-water hydrologic data for the Houston metropolitan area, Texas, water years 1990-95

USGS Publications Warehouse

Sneck-Fahrer, Debra A.; Liscum, Fred; East, Jeffery W.

2003-01-01

During water years 1990–95, data were collected at 24 U.S. Geological Survey streamflow-gaging stations, 21 rain gages, and 6 water-quality stations in the Houston metropolitan area, Texas. The data were collected as part of the Houston Urban Runoff Program, which began in water year 1964. Annual peaks were defined for the 24 streamflow-gaging stations in the study area. All stations had 10 or more years of record. Precipitation data from the 21 rain gages and discharge or stage data from 23 streamflow-gaging stations are available to develop storm hydrographs. One-hundred thirty-four samples were collected at six water-quality stations. The samples were analyzed for about 80 water-quality properties and constituents.

47 CFR 74.436 - Special requirements for automatic relay stations.

Code of Federal Regulations, 2010 CFR

2010-10-01

... RADIO SERVICES EXPERIMENTAL RADIO, AUXILIARY, SPECIAL BROADCAST AND OTHER PROGRAM DISTRIBUTIONAL...) An automatic relay station must be designed, installed, and protected so that the transmitter can...

47 CFR 74.436 - Special requirements for automatic relay stations.

Code of Federal Regulations, 2011 CFR

2011-10-01

... RADIO SERVICES EXPERIMENTAL RADIO, AUXILIARY, SPECIAL BROADCAST AND OTHER PROGRAM DISTRIBUTIONAL...) An automatic relay station must be designed, installed, and protected so that the transmitter can...

47 CFR 74.436 - Special requirements for automatic relay stations.

Code of Federal Regulations, 2013 CFR

2013-10-01

... RADIO SERVICES EXPERIMENTAL RADIO, AUXILIARY, SPECIAL BROADCAST AND OTHER PROGRAM DISTRIBUTIONAL...) An automatic relay station must be designed, installed, and protected so that the transmitter can...

47 CFR 74.436 - Special requirements for automatic relay stations.

Code of Federal Regulations, 2012 CFR

2012-10-01

... RADIO SERVICES EXPERIMENTAL RADIO, AUXILIARY, SPECIAL BROADCAST AND OTHER PROGRAM DISTRIBUTIONAL...) An automatic relay station must be designed, installed, and protected so that the transmitter can...

47 CFR 74.436 - Special requirements for automatic relay stations.

Code of Federal Regulations, 2014 CFR

2014-10-01

... RADIO SERVICES EXPERIMENTAL RADIO, AUXILIARY, SPECIAL BROADCAST AND OTHER PROGRAM DISTRIBUTIONAL...) An automatic relay station must be designed, installed, and protected so that the transmitter can...

47 CFR 74.791 - Digital call signs.

Code of Federal Regulations, 2010 CFR

2010-10-01

..., AUXILIARY, SPECIAL BROADCAST AND OTHER PROGRAM DISTRIBUTIONAL SERVICES Low Power TV, TV Translator, and TV... −D. (b) Digital television translator stations. Call signs for digital television translator stations...

Data transmission system with distributed microprocessors

DOEpatents

Nambu, Shigeo

1985-01-01

A data transmission system having a common request line and a special request line in addition to a transmission line. The special request line has priority over the common request line. A plurality of node stations are multi-drop connected to the transmission line. Among the node stations, a supervising station is connected to the special request line and takes precedence over other slave stations to become a master station. The master station collects data from the slave stations. The station connected to the common request line can assign a master control function to any station requesting to be assigned the master control function within a short period of time. Each station has an auto response control circuit. The master station automatically collects data by the auto response controlling circuit independently of the microprocessors of the slave stations.

Metal distribution in coral reef complex Cayo Arcas in the Gulf of Mexico.

PubMed

Cram, Silke; Ponce de León, Claudia A; Sommer, Irene; Miceli, Susi; Fernández, Pilar; Rivas, Hilda; Galicia, Leopoldo

2009-04-01

This study evaluated the spatial and temporal distribution of metals in the coral reef system Cayos Arcas and Triangulos in the Campeche Bank region, off the Yucatan peninsula in Mexico. No information has been generated before for the incorporation of natural and non-natural occurring metals, some of which are possibly endowed by the oil marine station Cayo Arcas. The multivariate exploratory study of the metals on the coral skeletons, showed the formation of two distinct groups. The metals that have the highest influence on the differentiation of the groups are the metals that are natural constituents of the coral skeletons, in particular Sr can explain much of the differences between the groups, and to a much lesser extent are the metals that could be indicators of pollution. This differentiation suggests that, in our case, the environment around the corals has a higher impact than the non-naturally occurring metals (and possible indicators of pollution). The two groups formed corresponded to: the coral cores influenced by open sea variables and the coral cores in the inner part of the keys which is less exposed to open sea variables. A chronological study was made to two samples that had the longest coral section and were situated in two clearly distinctive zones: an exposed surface subjected to high wave forces and another that was less exposed. Ni and Zn show an accumulation trend in both coral samples, while Ba showed an increase in incorporation around 1980 when the Cayo Arcas oil marine station was constructed.

47 CFR 73.68 - Sampling systems for antenna monitors.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 47 Telecommunication 4 2014-10-01 2014-10-01 false Sampling systems for antenna monitors. 73.68... RADIO BROADCAST SERVICES AM Broadcast Stations § 73.68 Sampling systems for antenna monitors. (a) Each AM station permittee authorized to construct a new directional antenna system which will be subject...

47 CFR 73.68 - Sampling systems for antenna monitors.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 47 Telecommunication 4 2013-10-01 2013-10-01 false Sampling systems for antenna monitors. 73.68... RADIO BROADCAST SERVICES AM Broadcast Stations § 73.68 Sampling systems for antenna monitors. (a) Each AM station permittee authorized to construct a new directional antenna system which will be subject...

47 CFR 73.68 - Sampling systems for antenna monitors.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 47 Telecommunication 4 2010-10-01 2010-10-01 false Sampling systems for antenna monitors. 73.68... RADIO BROADCAST SERVICES AM Broadcast Stations § 73.68 Sampling systems for antenna monitors. (a) Each AM station permittee authorized to construct a new directional antenna system which will be subject...

47 CFR 73.68 - Sampling systems for antenna monitors.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 47 Telecommunication 4 2012-10-01 2012-10-01 false Sampling systems for antenna monitors. 73.68... RADIO BROADCAST SERVICES AM Broadcast Stations § 73.68 Sampling systems for antenna monitors. (a) Each AM station permittee authorized to construct a new directional antenna system which will be subject...

47 CFR 73.68 - Sampling systems for antenna monitors.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 47 Telecommunication 4 2011-10-01 2011-10-01 false Sampling systems for antenna monitors. 73.68... RADIO BROADCAST SERVICES AM Broadcast Stations § 73.68 Sampling systems for antenna monitors. (a) Each AM station permittee authorized to construct a new directional antenna system which will be subject...

Vertical distribution and daily migrations of hyperiid amphipods in the northern Benguela in relation to water column stratification

NASA Astrophysics Data System (ADS)

Cornet, Carme; Gili, Josep-Maria

1993-11-01

The vertical distribution and migratory behaviour of hyperiid amphipods were studied in a series of tows carried out during a 48-h sampling period at an oceanic station at the northern edge of the Benguela System during a major penetration by Angola Current waters. A total of 49 species of hyperiid amphipods were collected; of these, Tetrathyrus forcipatus was the most abundant, with densities greater than two individuals per 10 m 3. Vibilia armata, Lestrigonus latissimus, L. bengalensis and Paratyphis promontorii were also highly abundant. During the sampling period most species were concentrated in the uppermost 40 m of the water column, though in other regions the vertical distribution of these same species has been reported to be broader. Only a few species were able to migrate through the thermocline. We hypothesize that both the non-migratory behaviour and the aggregation of individuals and species were caused by two primary factors: the existence of a strong thermocline, which hindered the transit of species to deeper layers, and abundant concentrations of gelatinous zooplankton above the thermocline. Hyperiids and the gelatinous zooplankton, particularly medusae and siphonophores, exhibited a close association during the sampling period, suggesting that hyperiids are able to partition their habitat by using the different medusan and siphonophoran species as specific substrates, thereby reducing interspecific competition.

Polycyclic aromatic hydrocarbon concentrations across the Florida Panhandle continental shelf and slope after the BP MC 252 well failure.

PubMed

Snyder, Richard A; Ederington-Hagy, Melissa; Hileman, Fredrick; Moss, Joseph A; Amick, Lauren; Carruth, Rebecca; Head, Marie; Marks, Joel; Tominack, Sarah; Jeffrey, Wade H

2014-12-15

The Florida Panhandle continental shelf environment was exposed to oil from the BP oil well failure in the Gulf of Mexico during 2010. Floating mats of oil were documented by satellite, but the distribution of dissolved components of the oil in this region was unknown. Shipek® grab samples of sediments were taken during repeated cruises between June 2010 and June 2012 to test for selected polycyclic aromatic hydrocarbons (PAHs) as indicators of this contamination. Sediments were collected as composite samples, extracted using standard techniques, and PAHs were quantified by GC/MS-SIM. PAHs in samples from the continental slope in May 2011 were highest near to the failed well site and were reduced in samples taken one year later. PAHs from continental shelf sediments during the spill (June 2010) ranged from 10 to 165 ng g(-1). Subsequent cruises yielded variable and reduced amounts of PAHs across the shelf. The data suggest that PAHs were distributed widely across the shelf, and their subsequent loss to background levels suggests these compounds were of oil spill origin. PAH half-life estimates by regression were 70-122 days for slope and 201 days for shelf stations. Copyright © 2014 Elsevier Ltd. All rights reserved.

Sampling and Analysis of Atmospheric Pcdd/fs in South China Sea and Background Area in Vietnam

NASA Astrophysics Data System (ADS)

Chi, K.; Thuan, N. T.; Anh, N. X.; Lin, N.

2011-12-01

During the Vietnam conflict, United States (US) forces sprayed a greater volume of defoliant (Agent Orange) with higher PCDD/F content in central Vietnam. The Vietnamese have been exposed to these levels during spraying primarily through contact with former US military infrastructure. In this study, the concentrations of atmospheric PCDD/Fs observed at three background stations (Fig. 1) at Dongsha Island (Sites A) in South China Sea, Da Nang (Site B) city and Son La (Site C) in central and northern Vietnam, respectively, to further understand the PCDD/F contamination in Vietnam. The Measurements indicated that the atmospheric PCDD/F concentrations at Sites A, B and C were 1.66~10.8, 23.4~146 and 11.1~59.5 fg I-TEQ/m3, respectively, during the spring season in 2010 and 2011. The significantly lower PCDD/F concentrations and contents in suspended particles (23.7~33.9 pg I-TEQ/g-TSP) measured at Site A in the South China Sea can be attributed to the lack of any combustion sources within almost 300 km of this island. However, the significantly higher PCDD/F contents in suspended particles (270~300 pg I-TEQ/g-TSP) were measured at Site B in central Vietnam. In addition, Fig. 2 shows that the distribution of PCDD/F congeners measured at Da Nang station was quite different from those measured at other station with high PCDD distribution (>85%) especially in OCDD (>70%). We consider that the high fraction of PCDDs observed at Da Nang probably originated as anthropogenic emission from specific source in Vietnam.

Frequency Analysis Using Bootstrap Method and SIR Algorithm for Prevention of Natural Disasters

NASA Astrophysics Data System (ADS)

Kim, T.; Kim, Y. S.

2017-12-01

The frequency analysis of hydrometeorological data is one of the most important factors in response to natural disaster damage, and design standards for a disaster prevention facilities. In case of frequency analysis of hydrometeorological data, it assumes that observation data have statistical stationarity, and a parametric method considering the parameter of probability distribution is applied. For a parametric method, it is necessary to sufficiently collect reliable data; however, snowfall observations are needed to compensate for insufficient data in Korea, because of reducing the number of days for snowfall observations and mean maximum daily snowfall depth due to climate change. In this study, we conducted the frequency analysis for snowfall using the Bootstrap method and SIR algorithm which are the resampling methods that can overcome the problems of insufficient data. For the 58 meteorological stations distributed evenly in Korea, the probability of snowfall depth was estimated by non-parametric frequency analysis using the maximum daily snowfall depth data. The results show that probabilistic daily snowfall depth by frequency analysis is decreased at most stations, and most stations representing the rate of change were found to be consistent in both parametric and non-parametric frequency analysis. This study shows that the resampling methods can do the frequency analysis of the snowfall depth that has insufficient observed samples, which can be applied to interpretation of other natural disasters such as summer typhoons with seasonal characteristics. Acknowledgment.This research was supported by a grant(MPSS-NH-2015-79) from Disaster Prediction and Mitigation Technology Development Program funded by Korean Ministry of Public Safety and Security(MPSS).

Applicability of AgMERRA Forcing Dataset to Fill Gaps in Historical in-situ Meteorological Data

NASA Astrophysics Data System (ADS)

Bannayan, M.; Lashkari, A.; Zare, H.; Asadi, S.; Salehnia, N.

2015-12-01

Integrated assessment studies of food production systems use crop models to simulate the effects of climate and socio-economic changes on food security. Climate forcing data is one of those key inputs of crop models. This study evaluated the performance of AgMERRA climate forcing dataset to fill gaps in historical in-situ meteorological data for different climatic regions of Iran. AgMERRA dataset intercompared with in- situ observational dataset for daily maximum and minimum temperature and precipitation during 1980-2010 periods via Root Mean Square error (RMSE), Mean Absolute Error (MAE) and Mean Bias Error (MBE) for 17 stations in four climatic regions included humid and moderate, cold, dry and arid, hot and humid. Moreover, probability distribution function and cumulative distribution function compared between model and observed data. The results of measures of agreement between AgMERRA data and observed data demonstrated that there are small errors in model data for all stations. Except for stations which are located in cold regions, model data in the other stations illustrated under-prediction for daily maximum temperature and precipitation. However, it was not significant. In addition, probability distribution function and cumulative distribution function showed the same trend for all stations between model and observed data. Therefore, the reliability of AgMERRA dataset is high to fill gaps in historical observations in different climatic regions of Iran as well as it could be applied as a basis for future climate scenarios.

Influence of seasonal environmental variables on the distribution of presumptive fecal Coliforms around an Antarctic research station.

PubMed

Hughes, Kevin A

2003-08-01

Factors affecting fecal microorganism survival and distribution in the Antarctic marine environment include solar radiation, water salinity, temperature, sea ice conditions, and fecal input by humans and local wildlife populations. This study assessed the influence of these factors on the distribution of presumptive fecal coliforms around Rothera Point, Adelaide Island, Antarctic Peninsula during the austral summer and winter of February 1999 to September 1999. Each factor had a different degree of influence depending on the time of year. In summer (February), although the station population was high, presumptive fecal coliform concentrations were low, probably due to the biologically damaging effects of solar radiation. However, summer algal blooms reduced penetration of solar radiation into the water column. By early winter (April), fecal coliform concentrations were high, due to increased fecal input by migrant wildlife, while solar radiation doses were low. By late winter (September), fecal coliform concentrations were high near the station sewage outfall, as sea ice formation limited solar radiation penetration into the sea and prevented wind-driven water circulation near the outfall. During this study, environmental factors masked the effect of station population numbers on sewage plume size. If sewage production increases throughout the Antarctic, environmental factors may become less significant and effective sewage waste management will become increasingly important. These findings highlight the need for year-round monitoring of fecal coliform distribution in Antarctic waters near research stations to produce realistic evaluations of sewage pollution persistence and dispersal.

Pitot-pressure distributions of the flow field of a delta-wing orbiter

NASA Technical Reports Server (NTRS)

Cleary, J. W.

1972-01-01

Pitot pressure distributions of the flow field of a 0.0075-scale model of a typical delta wing shuttle orbiter are presented. Results are given for the windward and leeward sides on centerline in the angle-of-attack plane from wind tunnel tests conducted in air. Distributions are shown for three axial stations X/L = .35, .60, and .98 and for angles of attack from 0 to 60 deg. The tests were made at a Mach number of 7.4 and for Reynolds numbers based on body length from 1,500,000 to 9,000,000. The windward distributions at the two survey stations forward of the body boat tail demonstrate the compressive aspects of the flow from the shock wave to the body. Conversely, the distributions at the aft station display an expansion of the flow that is attributed to body boat tail. On the lee side, results are given at low angles of attack that illustrate the complicating aspects of the canopy on the flow field, while results are given to show the effects of flow separation at high angles of attack.

Design And Development Of An Autonomous Radar Receiver For The Detection Of Ultra High Energy Cosmic Rays

NASA Astrophysics Data System (ADS)

Kunwar, Samridha

The detection of ultra-high energy cosmic rays is constrained by their flux, requiring detectors with apertures of hundreds or even thousands of square kilometers and close to one hundred percent duty cycle. The sheer scale that would be required of conventional detectors, to acquire sufficient statistics for energy, composition or anisotropy studies, means that new techniques that reduce manpower and financial resources are continually being sought. In this dissertation, the development of a remote sensing technique based observatory known as bistatic radar, which aims to achieve extensive coverage of the Earth's surface, cf. Telescope Array's 700 km2 surface detector, is discussed. Construction of the radar projects transmitter station was completed in the summer of 2013, and remote receiver stations were deployed in June and November of 2014. These stations accomplish radar echo detection using an analog signal chain. Subject to less radio interference, the remote stations add stereoscopic measurement capabilities that theoretically allow unique determination of cosmic ray geometry and core location. An FPGA is used as a distributed data processing node within the project. The FPGA provides triggering logic for data sampled at 200 MSa/s, detecting Cosmic Ray shower echoes chirping at -1 to -10 Megahertz/microsecond (depending on the geometry) for several microseconds. The data acquisition system with low power consumption at a cost that is also comparatively inexpensive is described herein.

PAHs sensitivity of picophytoplankton populations in the Red Sea.

PubMed

Kottuparambil, Sreejith; Agusti, Susana

2018-04-25

In this study, we investigated the in situ responses of Red Sea picophytoplankton, the dominant phytoplankton group in the oligotrophic ocean, to two toxic polycyclic aromatic hydrocarbons (PAHs), phenanthrene and pyrene. The experiments were conducted across a latitudinal gradient of the Saudi Arabian Red Sea, an area sensitive to oil pollution. We observed significant adverse effects on the growth and abundance of the picocyanobacteria Synechococcus and picoeukaryotes, at all stations sampled. Prochlorococcus, which was abundant only at one of the stations, also appeared to be affected. Pyrene was found to be more toxic to phytoplankton at all stations. In general, picoeukaryotes exhibited higher sensitivity to PAHs than Synechococcus. Populations in the highly oligotrophic Northern region of the Red Sea were more tolerant to PAHs, presumably influenced by the natural selection of more resistant strains of phytoplankton due to the prolonged exposure to PAHs. Toxicity threshold values estimated here are higher than those reported for picophytoplankton from other oligotrophic marine waters and exceed by far the natural levels of PAHs in many oceans. Our findings reveal a possible adaptation of picophytoplankton populations to oil-related contaminants, which may clearly influence their spatial distribution patterns in the Red Sea. Copyright © 2018 Elsevier Ltd. All rights reserved.

Characterization of airborne particles in an open pit mining region.

PubMed

Huertas, José I; Huertas, María E; Solís, Dora A

2012-04-15

We characterized airborne particle samples collected from 15 stations in operation since 2007 in one of the world's largest opencast coal mining regions. Using gravimetric, scanning electron microscopy (SEM-EDS), and X-ray photoelectron spectroscopy (XPS) analysis the samples were characterized in terms of concentration, morphology, particle size distribution (PSD), and elemental composition. All of the total suspended particulate (TSP) samples exhibited a log-normal PSD with a mean of d=5.46 ± 0.32 μm and σ(ln d)=0.61 ± 0.03. Similarly, all particles with an equivalent aerodynamic diameter less than 10 μm (PM(10)) exhibited a log-normal type distribution with a mean of d=3.6 ± 0.38 μm and σ(ln d)=0.55 ± 0.03. XPS analysis indicated that the main elements present in the particles were carbon, oxygen, potassium, and silicon with average mass concentrations of 41.5%, 34.7%, 11.6%, and 5.7% respectively. In SEM micrographs the particles appeared smooth-surfaced and irregular in shape, and tended to agglomerate. The particles were typically clay minerals, including limestone, calcite, quartz, and potassium feldspar. Copyright © 2012 Elsevier B.V. All rights reserved.

A synchrotron X-ray diffraction deconvolution method for the measurement of residual stress in thermal barrier coatings as a function of depth.

PubMed

Li, C; Jacques, S D M; Chen, Y; Daisenberger, D; Xiao, P; Markocsan, N; Nylen, P; Cernik, R J

2016-12-01

The average residual stress distribution as a function of depth in an air plasma-sprayed yttria stabilized zirconia top coat used in thermal barrier coating (TBC) systems was measured using synchrotron radiation X-ray diffraction in reflection geometry on station I15 at Diamond Light Source, UK, employing a series of incidence angles. The stress values were calculated from data deconvoluted from diffraction patterns collected at increasing depths. The stress was found to be compressive through the thickness of the TBC and a fluctuation in the trend of the stress profile was indicated in some samples. Typically this fluctuation was observed to increase from the surface to the middle of the coating, decrease a little and then increase again towards the interface. The stress at the interface region was observed to be around 300 MPa, which agrees well with the reported values. The trend of the observed residual stress was found to be related to the crack distribution in the samples, in particular a large crack propagating from the middle of the coating. The method shows promise for the development of a nondestructive test for as-manufactured samples.

Distribution and Analysis of Heavy Metals Contamination in Soil, Perlis, Malaysia

NASA Astrophysics Data System (ADS)

Nihla Kamarudzaman, Ain; Woo, Yee Shan; Jalil, Mohd Faizal Ab

2018-03-01

The concentration of six heavy metals such as Cu, Cr, Ni, Cd, Zn and Mn were studied in the soils around Perlis. The aim of the study is to assess the heavy metals contamination distribution due to industrialisation and agricultural activities. Soil samples were collected at depth of 0 - 15 cm in five stations around Perlis. The soil samples are subjected to soil extraction and the concentration of heavy metals was determined via ICP - OES. Overall concentrations of Cr, Cu, Zn, Ni, Cd and Mn in the soil samples ranged from 0.003 - 0.235 mg/L, 0.08 - 41.187 mg/L, 0.065 - 45.395 mg/L, 0.031 - 2.198 mg/L, 0.01 - 0.174 mg/L and 0.165 - 63.789 mg/L respectively. The concentration of heavy metals in the soil showed the following decreasing trend, Mn > Zn > Cu > Ni > Cr > Cd. From the result, the level of heavy metals in the soil near centralised Chuping industrial areas gives maximum value compared to other locations in Perlis. As a conclusion, increasing anthropogenic activities have influenced the environment, especially in increasing the pollution loading.

The state-of-the-art of dc power distribution systems/components for space applications

NASA Technical Reports Server (NTRS)

Krauthamer, S.

1988-01-01

This report is a survey of the state of the art of high voltage dc systems and components. This information can be used for consideration of an alternative secondary distribution (120 Vdc) system for the Space Station. All HVdc components have been prototyped or developed for terrestrial, aircraft, and spacecraft applications, and are applicable for general space application with appropriate modification and qualification. HVdc systems offer a safe, reliable, low mass, high efficiency and low EMI alternative for Space Station secondary distribution.

47 CFR 74.780 - Broadcast regulations applicable to translators, low power, and booster stations.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 47 Telecommunication 4 2010-10-01 2010-10-01 false Broadcast regulations applicable to translators... PROGRAM DISTRIBUTIONAL SERVICES Low Power TV, TV Translator, and TV Booster Stations § 74.780 Broadcast regulations applicable to translators, low power, and booster stations. The following rules are applicable to...

Surface-water-quality assessment of the Kentucky River Basin, Kentucky; fixed-station network and selected water-quality data, April 1987 through August 1991

USGS Publications Warehouse

Griffin, M.S.; Martin, G.R.; White, K.D.

1994-01-01

This report describes selected data-collection activities and the associated data collected during the Kentucky River Basin pilot study of the U.S. Geological Survey's National Water-Quality Assessment Program. The data are intended to provide a nationally consistent description and improved understanding of current water quality in the basin. The data were collected at seven fixed stations that represent stream cross sections where constituent transport and water-quality trends can be evaluated. The report includes descriptions of (1) the basin; (2) the design of the fixed-station network; (3) the fixed-station sites; (4) the physical and chemical measurements; (5) the methods of sample collection, processing, and analysis; and (6) the quality-assurance and quality-control procedures. Water-quality data collected at the fixed stations during routine periodic sampling and supplemental high-flow sampling from April 1987 to August 1991 are presented.

The Use of Chlorophyll Fluorescence Lifetime to Assess Phytoplankton Physiology within a River-Dominated Environment

NASA Technical Reports Server (NTRS)

Hall, Callie M.; Miller, Richard L.; Redalje, Donald G.; Fernandez, Salvador M.

2002-01-01

Chlorophyll a fluorescence lifetime was measured for phytoplankton populations inhabiting the three physical zones surrounding the Mississippi River's terminus in the Gulf of Mexico. Observations of river discharge volume, nitrate + nitrite, silicate, phosphate, PAR (Photosynthetically Active Radiation) diffuse attenuation within the water column, salinity, temperature, SPM, and chl a concentration were used to characterize the distribution of chl fluorescence lifetime within a given region within restricted periods of time. 33 stations extending from the Mississippi River plume to the shelf break of the Louisiana coast were surveyed for analysis of chlorophyll fluorescence lifetime during two cruises conducted March 31 - April 6, 2000, and October 24 - November 1, 2000. At each station, two to three depths were chosen for fluorescence lifetime measurement to represent the vertical characteristics of the water column. Where possible, samples were taken from just below the surface and from just above and below the pycnocline. All samples collected were within the 1% light level of the water column (the euphotic zone). Upon collection, samples were transferred to amber Nalgene bottles and left in the dark for at least 15 minutes to reduce the effects of non-photochemical quenching and to insure that photosynthetic reaction centers were open. Before measurements within the phase fluorometer were begun, the instrument was allowed to warm up for no less than one hour.

Investigation of microbial diversity in a desert Mars-like environment: Mars Desert Research Station (MDRS), Utah

NASA Astrophysics Data System (ADS)

Direito, Maria Susana; Staats, Martijn; Foing, Bernard H.; Ehrenfreund, Pascale; Roling, Wilfred

The Utah Mars Desert Research Station (MDRS) harbours geo-morphology and geo-processes analogues to the planet Mars. Soil samples were collected during the EuroGeoMars campaign (from 24 January to 1 March 2009) from different locations and depths [1]. Samples were distributed among scientific collaborator institutes for analysis of microbial diversity, amino acid content and degradation, content of PAH or larger organic molecules, and respective soil properties. Our sample analysis had the objective of characterizing the microbial communities in this Mars analogue: DNA isolation, PCR (Polymerase Chain Reaction) using primers for DNA amplification of Bacteria, Archaea and Eukarya ribosomal RNA (rRNA) gene fragments, DGGE (Denaturing Gradient Gel Electrophoresis) and clone library construction with the final aim of sequencing. Results indicate that life is present in all the three domains of life (Archaea, Bacteria and Eukarya), while the most diversity was found in the domain Bacteria. Microorgan-isms are heterogeneously present and their identities are currently investigated. The obtained information will be later related to the other scientific analysis in order to obtain a better understanding of this Mars analogue site, which in turn will provide important information for the search for life on Mars. [1] Foing, B.H. et al . (2009). Exogeolab lander/rover instruments and EuroGeoMars MDRS campaign. LPI, 40, 2567.

An overview of the Ice Nuclei Research Unit Jungfraujoch/Cloud and Aerosol Characterization Experiment 2013 (INUIT-JFJ/CLACE-2013)

NASA Astrophysics Data System (ADS)

Schneider, Johannes

2014-05-01

Ice formation in mixed phase tropospheric clouds is an essential prerequisite for the formation of precipitation at mid-latitudes. Ice formation at temperatures warmer than -35°C is only possible via heterogeneous ice nucleation, but up to now the exact pathways of heterogeneous ice formation are not sufficiently well understood. The research unit INUIT (Ice NUcleation research unIT), funded by the Deutsche Forschungsgemeinschaft (DFG FOR 1525) has been established in 2012 with the objective to investigate heterogeneous ice nucleation by combination of laboratory studies, model calculation and field experiments. The main field campaign of the INUIT project (INUIT-JFJ) was conducted at the High Alpine Research Station Jungfraujoch (Swiss Alps, 3580 m asl) during January and February 2013, in collaboration with several international partners in the framework of CLACE2013. The instrumentation included a large set of aerosol chemical and physical analysis instruments (particle counters, particle sizers, particle mass spectrometers, cloud condensation nuclei counters, ice nucleus counters etc.), that were operated inside the Sphinx laboratory and sampled in mixed phase clouds through two ice selective inlets (Ice-CVI, ISI) as well as through a total aerosol inlet that was used for out-of-cloud aerosol measurements. Besides the on-line measurements, also samples for off-line analysis (ESEM, STXM) have been taken in and out of clouds. Furthermore, several cloud microphysics instruments were operated outside the Sphinx laboratory. First results indicate that a large fraction of ice residues sampled from mixed phase clouds contain organic material, but also mineral dust. Soot and lead were not found to be enriched in ice residues. The concentration of heterogeneous ice nuclei was found to be variable (ranging between < 1 and > 100 per liter) and to be strongly dependent on the operating conditions of the respective IN counter. The number size distribution of ice residues appears to show a bimodal distribution with a smaller mode having a modal diameter around 200 nm and a coarse mode at around 2 µm. During the cloud events evaluated so far, agreement between the number concentration of ice residues sampled through the Ice-CVI and the measured concentration of small ice crystals measured outside the laboratory could be achieved. The shape of small ice crystals was found to be mainly irregular. We acknowledge the International Foundation High Altitude Research Stations Jungfraujoch and Gornergrat (HFSJG), the help of the custodians at the Jungfraujoch station, and the funding by DFG (FOR 1525) and the federal state Hessen ("LOEWE-Schwerpunkt AmbiProbe").

Constructing a generalized network design model to study air distribution in ventilation networks in subway with a single-track tunnel

NASA Astrophysics Data System (ADS)

Lugin, IV

2018-03-01

In focus are the features of construction of the generalized design model for the network method to study air distribution in ventilation system in subway with the single-track tunnel. The generalizations, assumptions and simplifications included in the model are specified. The air distribution is calculated with regard to the influence of topology and air resistances of the ventilation network sections. The author studies two variants of the subway line: half-open and closed with dead end on the both sides. It is found that the total air exchange at a subway station depends on the station location within the line. The operating mode of fans remains unaltered in this case. The article shows that elimination of air leakage in the station ventilation room allows an increase in the air flow rate by 7–8% at the same energy consumption by fans. The influence of the stop of a train in the tunnel on the air distribution is illustrated.

Biological baseline data Youngs Bay, Oregon, 1974

DOE Office of Scientific and Technical Information (OSTI.GOV)

McMechan, K.J.; Higley, D.L.; Holton, R.L.

1975-04-01

This report presents biological baseline information gathered during the research project, Physical, Chemical and Biological Studies on Youngs Bay.'' Youngs Bay is a shallow embayment located on the south shore of the Columbia River, near Astoria, Oregon. Research on Youngs Bay was motivated by the proposed construction by Alumax Pacific Aluminum Corporation of an aluminum reduction plant at Warrenton, Oregon. The research was designed to provide biological baseline information on Youngs Bay in anticipation of potential harmful effects from plant effluents. The information collected concerns the kinds of animals found in the Youngs Bay area, and their distribution and seasonalmore » patterns of abundance. In addition, information was collected on the feeding habits of selected fish species, and on the life history and behavioral characteristics of the most abundant benthic amphipod, Corophium salmonis. Sampling was conducted at approximately three-week intervals, using commonly accepted methods of animal collection. Relatively few stations were sampled for fish, because of the need to standardize conditions of capture. Data on fish capture are reported in terms of catch-per-unit effort by a particular sampling gear at a specific station. Methods used in sampling invertebrates were generally more quantitative, and allowed sampling at a greater variety of places, as well as a valid basis for the computation of densities. Checklists of invertebrate species and fish species were developed from these samples, and are referred to throughout the report. The invertebrate checklist is more specific taxonomically than are tables reporting invertebrate densities. This is because the methods employed in identification were more precise than those used in counts. 9 refs., 27 figs., 25 tabs.« less

Rubidium distribution at atomic scale in high efficient Cu(In,Ga)Se2 thin-film solar cells

NASA Astrophysics Data System (ADS)

Vilalta-Clemente, Arantxa; Raghuwanshi, Mohit; Duguay, Sébastien; Castro, Celia; Cadel, Emmanuel; Pareige, Philippe; Jackson, Philip; Wuerz, Roland; Hariskos, Dimitrios; Witte, Wolfram

2018-03-01

The introduction of a rubidium fluoride post deposition treatment (RbF-PDT) for Cu(In,Ga)Se2 (CIGS) absorber layers has led to a record efficiency up to 22.6% for thin-film solar cell technology. In the present work, high efficiency CIGS samples with RbF-PDT have been investigated by atom probe tomography (APT) to reveal the atomic distribution of all alkali elements present in CIGS layers and compared with non-treated samples. A Scanning Electron Microscopy Dual beam station (Focused Ion Beam-Gas Injection System) as well as Transmission Kikuchi diffraction is used for atom probe sample preparation and localization of the grain boundaries (GBs) in the area of interest. The analysis of the 3D atomic scale APT reconstructions of CIGS samples with RbF-PDT shows that inside grains, Rb is under the detection limit, but the Na concentration is enhanced as compared to the reference sample without Rb. At the GBs, a high concentration of Rb reaching 1.5 at. % was found, and Na and K (diffusing from the glass substrate) are also segregated at GBs but at lower concentrations as compared to Rb. The intentional introduction of Rb leads to significant changes in the chemical composition of CIGS matrix and at GBs, which might contribute to improve device efficiency.

Sample processor for chemical analysis

NASA Technical Reports Server (NTRS)

Boettger, Heinz G. (Inventor)

1980-01-01

An apparatus is provided which can process numerous samples that must be chemically analyzed by the application of fluids such as liquid reagents, solvents and purge gases, as well as the application of dumps for receiving the applied fluid after they pass across the sample, in a manner that permits numerous samples to be processed in a relatively short time and with minimal manpower. The processor includes a rotor which can hold numerous cartridges containing inert or adsorbent material for holding samples, and a pair of stators on opposite sides of the rotor. The stators form stations spaced along the path of the cartridges which lie in the rotor, and each station can include an aperture in one stator through which a fluid can be applied to a cartridge resting at that station, and an aperture in the other stator which can receive the fluid which has passed through the cartridge. The stators are sealed to the ends of the cartridges lying on the rotor, to thereby isolate the stations from one another.

Annual radiological environmental operating report: Browns Ferry Nuclear Plant, 1992. Operations Services/Technical Programs

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

1993-04-01

This report describes the environmental radiological monitoring program conducted by TVA in the vicinity of Browns Ferry Nuclear Plant (BFN) in 1992. The program includes the collection of samples from the environment and the determination of the concentrations of radioactive materials in the samples. Samples are taken from stations in the general area of the plant and from areas not influenced by plant operations. Station locations are selected after careful consideration of the weather patterns and projected radiation doses to the various areas around the plant. Material sampled includes air, water, milk, foods, vegetation, soil, fish, sediment, and direct radiationmore » levels. Results from stations near the plant are compared with concentrations from control stations and with preoperational measurements to determine potential impacts of plant operations. Small amounts of Co-60 and Cs-134 were found in sediment samples downstream from the plant. This activity in stream sediment would result in no measurable increase over background in the dose to the general public.« less

47 CFR 73.6023 - Distributed transmission systems.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 47 Telecommunication 4 2010-10-01 2010-10-01 false Distributed transmission systems. 73.6023... distributed transmission system. [73 FR 74064, Dec. 5, 2008] ... RADIO BROADCAST SERVICES Class A Television Broadcast Stations § 73.6023 Distributed transmission...

Swanson in Node 2 with ACE samples

NASA Image and Video Library

2014-07-14

ISS040-E-060673 (14 July 2014) --- NASA astronaut Steve Swanson, Expedition 40 commander, works with test samples for the Advanced Colloids Experiment (ACE) at a work station in the Harmony node of the International Space Station.

A Bivariate Mixed Distribution with a Heavy-tailed Component and its Application to Single-site Daily Rainfall Simulation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Li, Chao ..; Singh, Vijay P.; Mishra, Ashok K.

2013-02-06

This paper presents an improved brivariate mixed distribution, which is capable of modeling the dependence of daily rainfall from two distinct sources (e.g., rainfall from two stations, two consecutive days, or two instruments such as satellite and rain gauge). The distribution couples an existing framework for building a bivariate mixed distribution, the theory of copulae and a hybrid marginal distribution. Contributions of the improved distribution are twofold. One is the appropriate selection of the bivariate dependence structure from a wider admissible choice (10 candidate copula families). The other is the introduction of a marginal distribution capable of better representing lowmore » to moderate values as well as extremes of daily rainfall. Among several applications of the improved distribution, particularly presented here is its utility for single-site daily rainfall simulation. Rather than simulating rainfall occurrences and amounts separately, the developed generator unifies the two processes by generalizing daily rainfall as a Markov process with autocorrelation described by the improved bivariate mixed distribution. The generator is first tested on a sample station in Texas. Results reveal that the simulated and observed sequences are in good agreement with respect to essential characteristics. Then, extensive simulation experiments are carried out to compare the developed generator with three other alternative models: the conventional two-state Markov chain generator, the transition probability matrix model and the semi-parametric Markov chain model with kernel density estimation for rainfall amounts. Analyses establish that overall the developed generator is capable of reproducing characteristics of historical extreme rainfall events and is apt at extrapolating rare values beyond the upper range of available observed data. Moreover, it automatically captures the persistence of rainfall amounts on consecutive wet days in a relatively natural and easy way. Another interesting observation is that the recognized ‘overdispersion’ problem in daily rainfall simulation ascribes more to the loss of rainfall extremes than the under-representation of first-order persistence. The developed generator appears to be a sound option for daily rainfall simulation, especially in particular hydrologic planning situations when rare rainfall events are of great importance.« less

Specimen Sample Preservation for Cell and Tissue Cultures

NASA Technical Reports Server (NTRS)

Meeker, Gabrielle; Ronzana, Karolyn; Schibner, Karen; Evans, Robert

1996-01-01

The era of the International Space Station with its longer duration missions will pose unique challenges to microgravity life sciences research. The Space Station Biological Research Project (SSBRP) is responsible for addressing these challenges and defining the science requirements necessary to conduct life science research on-board the International Space Station. Space Station will support a wide range of cell and tissue culture experiments for durations of 1 to 30 days. Space Shuttle flights to bring experimental samples back to Earth for analyses will only occur every 90 days. Therefore, samples may have to be retained for periods up to 60 days. This presents a new challenge in fresh specimen sample storage for cell biology. Fresh specimen samples are defined as samples that are preserved by means other than fixation and cryopreservation. The challenge of long-term storage of fresh specimen samples includes the need to suspend or inhibit proliferation and metabolism pending return to Earth-based laboratories. With this challenge being unique to space research, there have not been any ground based studies performed to address this issue. It was decided hy SSBRP that experiment support studies to address the following issues were needed: Fixative Solution Management; Media Storage Conditions; Fresh Specimen Sample Storage of Mammalian Cell/Tissue Cultures; Fresh Specimen Sample Storage of Plant Cell/Tissue Cultures; Fresh Specimen Sample Storage of Aquatic Cell/Tissue Cultures; and Fresh Specimen Sample Storage of Microbial Cell/Tissue Cultures. The objective of these studies was to derive a set of conditions and recommendations that can be used in a long duration microgravity environment such as Space Station that will permit extended storage of cell and tissue culture specimens in a state consistent with zero or minimal growth, while at the same time maintaining their stability and viability.

Mercury in Precipitation in Indiana, January 2004-December 2005

USGS Publications Warehouse

Risch, Martin R.; Fowler, Kathleen K.

2008-01-01

Mercury in precipitation was monitored during 2004-2005 at five locations in Indiana as part of the National Atmospheric Deposition Program-Mercury Deposition Network (NADP-MDN). Monitoring stations were operated at Roush Lake near Huntington, Clifty Falls State Park near Madison, Fort Harrison State Park near Indianapolis, Monroe County Regional Airport near Bloomington, and Indiana Dunes National Lakeshore near Porter. At these monitoring stations, precipitation amounts were measured continuously and weekly samples were collected for analysis of mercury by methods achieving detection limits as low as 0.05 ng/L (nanograms per liter). Wet deposition was computed as the product of mercury concentration and precipitation. The data were analyzed for seasonal patterns, temporal trends, and geographic differences. In the 2 years, 520 weekly samples were collected at the 5 monitoring stations and 448 of these samples had sufficient precipitation to compute mercury wet deposition. The 2-year mean mercury concentration at the five monitoring stations (normalized to the sample volume) was 10.6 ng/L. As a reference for comparison, the total mercury concentration in 41 percent of the samples analyzed was greater than the statewide Indiana water-quality standard for mercury (12 ng/L, protecting aquatic life) and 99 percent of the concentrations exceeded the most conservative Indiana water-quality criterion (1.3 ng/L, protecting wild mammals and birds). The normalized annual mercury concentration at Clifty Falls in 2004 was the fourth highest in the NADP-MDN in eastern North America that year. In 2005, the mercury concentrations at Clifty Falls and Indiana Dunes were the ninth highest in the NADP-MDN in eastern North America. At the five monitoring stations during the study period, the mean weekly total mercury deposition was 0.208 ug/m2 (micrograms per square meter) and mean annual total mercury deposition was 10.8 ug/m2. The annual mercury deposition at Clifty Falls in 2004 and 2005 was in the top 25 percent of the NADP-MDN stations in eastern North America. Mercury concentrations and deposition varied at the five monitoring stations during 2004-2005. Mercury concentrations in wet-deposition samples ranged from 1.2 to 116.6 ng/L and weekly mercury deposition ranged from 0.002 to 1.74 ug/m2. Data from weekly samples exhibited seasonal patterns. During April through September, total mercury concentrations and deposition were higher than the median for all samples. Annual precipitation at four of the five monitoring stations was within 10 percent of normal both years, with the exception of Indiana Dunes, where precipitation was 23 percent below normal in 2005. Episodes of high mercury deposition, which were the top 10 percent of weekly mercury deposition at the five monitoring stations, contributed 39 percent of all mercury deposition during 2004-2005. Mercury deposition more than 1.04 ug/m2 (5 times the mean weekly deposition) was recorded for 12 samples. These episodes of highest mercury deposition were recorded at all five monitoring stations, but the most (7 of 12) were at Clifty Falls and contributed 34.4 percent of the total deposition at that station during 2004-2005. Weekly samples with high mercury deposition may help to explain the differences in annual mercury deposition among the five monitoring stations in Indiana. A statistical evaluation of the monitoring data for 2001-2005 indicated several statistically significant temporal trends. A statewide (5-station) decrease (p = 0.007) in mercury deposition and a statewide decrease (p = 0.059) in mercury concentration were shown. Decreases in mercury deposition (p = 0.061 and p = 0.083) were observed at Roush Lake and Bloomington. A statistically significant trend was not observed for precipitation at the five monitoring stations during this 5-year period. A potential explanation for part of the statewide decrease in mercury concentration and mercury deposition was a 2

Calculated spanwise lift distributions, influence functions, and influence coefficients for unswept wings in subsonic flow

NASA Technical Reports Server (NTRS)

Diederich, Franklin W; Zlotnick, Martin

1955-01-01

Spanwise lift distributions have been calculated for nineteen unswept wings with various aspect ratios and taper ratios and with a variety of angle-of-attack or twist distributions, including flap and aileron deflections, by means of the Weissinger method with eight control points on the semispan. Also calculated were aerodynamic influence coefficients which pertain to a certain definite set of stations along the span, and several methods are presented for calculating aerodynamic influence functions and coefficients for stations other than those stipulated. The information presented in this report can be used in the analysis of untwisted wings or wings with known twist distributions, as well as in aeroelastic calculations involving initially unknown twist distributions.

Analysis of the Magnitude and Frequency of Peak Discharge and Maximum Observed Peak Discharge in New Mexico and Surrounding Areas

USGS Publications Warehouse

Waltemeyer, Scott D.

2008-01-01

Estimates of the magnitude and frequency of peak discharges are necessary for the reliable design of bridges, culverts, and open-channel hydraulic analysis, and for flood-hazard mapping in New Mexico and surrounding areas. The U.S. Geological Survey, in cooperation with the New Mexico Department of Transportation, updated estimates of peak-discharge magnitude for gaging stations in the region and updated regional equations for estimation of peak discharge and frequency at ungaged sites. Equations were developed for estimating the magnitude of peak discharges for recurrence intervals of 2, 5, 10, 25, 50, 100, and 500 years at ungaged sites by use of data collected through 2004 for 293 gaging stations on unregulated streams that have 10 or more years of record. Peak discharges for selected recurrence intervals were determined at gaging stations by fitting observed data to a log-Pearson Type III distribution with adjustments for a low-discharge threshold and a zero skew coefficient. A low-discharge threshold was applied to frequency analysis of 140 of the 293 gaging stations. This application provides an improved fit of the log-Pearson Type III frequency distribution. Use of the low-discharge threshold generally eliminated the peak discharge by having a recurrence interval of less than 1.4 years in the probability-density function. Within each of the nine regions, logarithms of the maximum peak discharges for selected recurrence intervals were related to logarithms of basin and climatic characteristics by using stepwise ordinary least-squares regression techniques for exploratory data analysis. Generalized least-squares regression techniques, an improved regression procedure that accounts for time and spatial sampling errors, then were applied to the same data used in the ordinary least-squares regression analyses. The average standard error of prediction, which includes average sampling error and average standard error of regression, ranged from 38 to 93 percent (mean value is 62, and median value is 59) for the 100-year flood. The 1996 investigation standard error of prediction for the flood regions ranged from 41 to 96 percent (mean value is 67, and median value is 68) for the 100-year flood that was analyzed by using generalized least-squares regression analysis. Overall, the equations based on generalized least-squares regression techniques are more reliable than those in the 1996 report because of the increased length of record and improved geographic information system (GIS) method to determine basin and climatic characteristics. Flood-frequency estimates can be made for ungaged sites upstream or downstream from gaging stations by using a method that transfers flood-frequency data at the gaging station to the ungaged site by using a drainage-area ratio adjustment equation. The peak discharge for a given recurrence interval at the gaging station, drainage-area ratio, and the drainage-area exponent from the regional regression equation of the respective region is used to transfer the peak discharge for the recurrence interval to the ungaged site. Maximum observed peak discharge as related to drainage area was determined for New Mexico. Extreme events are commonly used in the design and appraisal of bridge crossings and other structures. Bridge-scour evaluations are commonly made by using the 500-year peak discharge for these appraisals. Peak-discharge data collected at 293 gaging stations and 367 miscellaneous sites were used to develop a maximum peak-discharge relation as an alternative method of estimating peak discharge of an extreme event such as a maximum probable flood.

Occurrence of species-rich crab fauna in a human-impacted mangrove forest questions the application of community analysis as an environmental assessment tool

NASA Astrophysics Data System (ADS)

Geist, Simon Joscha; Nordhaus, Inga; Hinrichs, Saskia

2012-01-01

Diversity and composition of the intertidal brachyuran crab community in the Segara Anakan Lagoon (SAL), Java, Indonesia, during the dry season of 2005 and the rainy season of 2006, shows that crab community composition and structure alone appeared to be poor indicators for the state of a forest in terms of tree diversity and wood-cutting intensity. The lagoon is surrounded by the largest mangrove stand in Java and is under constant anthropogenic pressure, mainly due to logging, land conversion for agriculture, overfishing and industrial pollution. This study aims to determine the crab community composition at different sites of the lagoon in relation to vegetation composition and sediment parameters. In addition it investigates if mangrove crabs can be used as bioindicators to describe the environmental state of mangrove forests (tree diversity, degree of logging). It was assumed to find a low crab diversity and species richness and a strong dominance of a single species at highly disturbed forest sites compared to moderately disturbed sites. A stratified, hierarchical design was used to sample the crab fauna at 13 stations distributed over the entire lagoon. Additionally, abiotic parameters and vegetation composition were recorded. In total 6463 crabs were caught belonging to 49 species, 5 superfamilies and 10 families, with Ocypodidae and Sesarmidae being the families of most note. Mean density of adult crabs was 27.7 individuals*m -2 and mean biomass was 12.8 g wet mass*m -2 or 1.3 g ash free dry mass*m -2. Density and biomass varied strongly within and between stations but they where within the range reported for other mangrove forests of the Indo-West-Pacific. Species composition was significantly different between stations. The distribution of facultatively leaf-feeding grapsid crabs was related to vegetation parameters (tree, seedling and undergrowth density), but the occurrence of single crab and tree species was not correlated. The distribution of ocypodid crabs, feeding on detritus and microphytobenthos, correlated with sediment characteristics like median grain size and organic content. The crab community was strongly dominated by one species at six stations, however, this was not correlated to the degree of logging. Leaf-feeding crab and mangrove tree diversity was correlated at areas of one hectare (stations), but not at a lower spatial scale (areas of 100 m 2, "zone"). Species richness of leaf-feeding crabs was not linked to forest diversity. Hence a functional relation between leaf-feeding crab and tree species diversity could not be proven.

The Global Atmosphere Watch Aerosol Programme

NASA Astrophysics Data System (ADS)

Baltensperger, U.

2003-04-01

The Global Atmosphere Watch (GAW) programme is a WMO sponsored activity and currently supported by about 80 WMO member countries. It is the goal of GAW to develop and maintain long-term measurements of atmospheric constituents in order to detect trends, develop aerosol predictive capabilities and understand proc- esses. With respect to aerosols, the objective of GAW is to support a global network determining the spatio-temporal distribution of aerosol properties related to climate forcing and air quality up to multi-decadal time scales. The GAW network consists of 22 Global stations and some 300 Regional stations. The Scientific Advisory Group (SAG) for Aerosols will soon publish their recommendations for aerosol measurements. Each site should have an acceptable aerosol sampling inlet. Regional stations measure aerosol optical depth, as well as the aerosol light scattering and absorption coefficient. If possible these should be complemented by routine mass concentration and composition measurements in two aerosol size fractions. At Global stations, a larger number of measurements are desirable. These include the Regional parameters list above as well as the light scattering, hemispheric backscat- tering, and absorption coefficients at various wavelengths, aerosol number concen- tration, cloud condensation nuclei (CCN) concentration at 0.5% supersaturation, and diffuse, global and direct solar radiation. Additional parameters such as the aerosol size distribution, detailed size fractionated chemical composition, dependence of aerosol properties on relative humidity, CCN concentration at various supersatura- tions, and the vertical distribution of aerosol properties should be measured intermit- tently at Global stations. Examples from the Jungfraujoch (Swiss Alps, 3580 m asl) will be given, where many of the parameters listed above are measured. Data are delivered to and made available by the World Data Centre for Aerosols (WDCA, located in Ispra, Italy http://ies.jrc.cec.eu.int/wdca/) using the NARSTO data exchange standard. The Institute for Tropospheric Research in Leipzig hosts a GAW World Calibration Centre (WCC) for physical aerosol parameters. A host for the chemical parameters still must be located. None of the Global sites perform a full set of measurements, and many Regional sites have not yet started with aerosol ac- tivities at all. Capacity building and fund raising are therefore important priorities in order to achieve the goals of the GAW global aerosol programme. It should be em- phasized that GAW works with many partners in the World Meteorological Organi- zation as well as other agencies in an attempt to develop an integrated system of satellite and non-satellite observations of the global aerosol.

Exposure level and distribution characteristics of airborne bacteria and fungi in Seoul metropolitan subway stations.

PubMed

Kim, Ki Youn; Kim, Yoon Shin; Kim, Daekeun; Kim, Hyeon Tae

2011-01-01

The exposure level and distribution characteristics of airborne bacteria and fungi were assessed in the workers' activity areas (station office, bedroom, ticket office and driver's seat) and passengers' activity areas (station precinct, inside the passenger carriage, and platform) of the Seoul metropolitan subway. Among investigated areas, the levels of airborne bacteria and fungi in the workers' bedroom and station precincts were relatively high. No significant difference was found in the concentration of airborne bacteria and fungi between the underground and above ground activity areas of the subway. The genera identified in all subway activity areas with a 5% or greater detection rate were Staphylococcus, Micrococcus, Bacillus and Corynebacterium for airborne bacteria and Penicillium, Cladosporium, Chrysosporium, Aspergillus for airborne fungi. Staphylococcus and Micrococcus comprised over 50% of the total airborne bacteria and Penicillium and Cladosporium comprised over 60% of the total airborne fungi, thus these four genera are the predominant genera in the subway station.

Vertical observation of molecular hydrogen and carbon monoxide: Implication for non-photochemical H2 production at ocean surface and subsurface

NASA Astrophysics Data System (ADS)

Kawagucci, S.; Narita, T.; Obata, H.; Ogawa, H.; Gamo, T.

2009-12-01

Biological nitrogen fixation is a key metabolism controlling marine N-cycling and also known as a main H2 source. Recently, it was proposed that a monitoring of surface H2 concentration could be used quickly to figure out the spatial extent of biological nitrogen fixation activity without onboard incubation required for currently used methods for detecting the activity. However, H2 behavior in ocean water was still unresolved. This study carried out vertical observation of H2 and CO concentrations in south of Japan, western North Pacific. Because carbon monoxide, CO, in seawater has no relation with nitrogen fixation metabolism and is produced dominantly by the photochemical reaction, which is an altanative H2 source, simultaneous observation and comparison of H2 and CO concentration is helpful to investigate H2 behavior in ocean water. Reductive gases in seawater were observed during the R/V Tansei-maru KT-08-14 cruise by using a wired CTD-CMS (CTD-carousel multiple sampling) system to conduct vertical sampling (at most 200 m depth) and by using a plastic bucket for sampling surface seawater. The sample in the Niskin-X bottle was directed to the bottom of a 120 mL brown-colored glass vial allowed to overflow by 2 volumes before the tube was slowly withdrawn. After the addition of 0.5 mL HgCl2-saturated solution for poisoning, the PTFE-lined butyl-gum septum was used to cap the vials. Molecular hydrogen (H2) and carbon monoxide (CO) were analyzed at an onboard laboratory within 6 hours after subsampling. 20 mL of sample water was substituted by 20 mL of H2- and CO-free air using a gas-tight syringe; then the vial was put on an automatic shaker and shaken upside down for 6 minutes to achieve a complete equilibrium between the dissolved and head space gases in the vial. The equilibrated headspace was taken by another gas-tight syringe and then injected into a gas chromatograph equipped with a trace reduced gas detector. Vertical distribution of dissolved H2 and CO concentration were observed. Apparently different vertical distributions between H2 and CO concentration were revealed at all the observed stations. At a station where N-nutrient was depleted through surface mixed layer, H2 was supersaturated at the surface while CO concentration was constant through the depths. In contrast, at another station where some amount of terrestrial humic matter was introduced into the surface, H2 concentration was constantly undersaturated through the depth while vertical distribution of CO concentration showed the highest at the surface and exponentially decreased to deep. These facts suggest that H2 production involved with nitrogen fixation played an important role for H2 behavior in ocean water while photochemical H2 production would be a minor process. In addition to the surface, H2 supersaturation accoumpanied with little CO concentration rise were observed at depths just below the mixed layer in pycnocline with Chlorophyll maximum.

Predictive models of energy consumption in multi-family housing in College Station, Texas

NASA Astrophysics Data System (ADS)

Ali, Hikmat Hummad

Patterns of energy consumption in apartment buildings are different than those in single-family houses. Apartment buildings have different physical characteristics, and their inhabitants have different demographic attributes. This study develops models that predict energy usage in apartment buildings in College Station. This is accomplished by analyzing and identifying the predictive variables that affect energy usage, studying the consumption patterns, and creating formulas based on combinations of these variables. According to the hypotheses and the specific research context, a cross-sectional design strategy is adopted. This choice implies analyses across variations within a sample of fourplex apartments in College Station. The data available for analysis include the monthly billing data along with the physical characteristics of the building, climate data for College Station, and occupant demographic characteristics. A simple random sampling procedure is adopted. The sample size of 176 apartments is drawn from the population in such a way that every possible sample has the same chance of being selected. Statistical methods used to interpret the data include univariate analysis (mean, standard deviation, range, and distribution of data), correlation analysis, regression analysis, and ANOVA (analyses of variance). The results show there are significant differences in cooling efficiency and actual energy consumption among different building types, but there are no significant differences in heating consumption. There are no significant differences in actual energy consumption between student and non-student groups or among ethnic groups. The findings indicate that there are significant differences in actual energy consumption among marital status groups and educational level groups. The multiple regression procedures show there is a significant relationship between normalized annual consumption and the combined variables of floor area, marital status, dead band, construction material, summer thermostat setting, heating, slope, and base load, as well as a relationship between cooling slope and the combined variables of share wall, floor level, summer thermostat setting, external wall, and American household. In addition, there is a significant relationship between heating slope and the combined variables of winter thermostat setting, market value, student, and rent. The results also indicate there is a relationship between base load and the combined variables of floor area, market value, age of the building, marital status, student, and summer thermostat setting.

Prototype space station automation system delivered and demonstrated at NASA

NASA Technical Reports Server (NTRS)

Block, Roger F.

1987-01-01

The Automated Subsystem Control for Life Support System (ASCLSS) program has successfully developed and demonstrated a generic approach to the automation and control of Space Station subsystems. The hierarchical and distributed real time controls system places the required controls authority at every level of the automation system architecture. As a demonstration of the automation technique, the ASCLSS system automated the Air Revitalization Group (ARG) of the Space Station regenerative Environmental Control and Life Support System (ECLSS) using real-time, high fidelity simulators of the ARG processess. This automation system represents an early flight prototype and an important test bed for evaluating Space Station controls technology including future application of ADA software in real-time control and the development and demonstration of embedded artificial intelligence and expert systems (AI/ES) in distributed automation and controls systems.

Mesoscale eddies: hotspots of prokaryotic activity and differential community structure in the ocean.

PubMed

Baltar, Federico; Arístegui, Javier; Gasol, Josep M; Lekunberri, Itziar; Herndl, Gerhard J

2010-08-01

To investigate the effects of mesoscale eddies on prokaryotic assemblage structure and activity, we sampled two cyclonic eddies (CEs) and two anticyclonic eddies (AEs) in the permanent eddy-field downstream the Canary Islands. The eddy stations were compared with two far-field (FF) stations located also in the Canary Current, but outside the influence of the eddy field. The distribution of prokaryotic abundance (PA), bulk prokaryotic heterotrophic activity (PHA), various indicators of single-cell activity (such as nucleic acid content, proportion of live cells, and fraction of cells actively incorporating leucine), as well as bacterial and archaeal community structure were determined from the surface to 2000 m depth. In the upper epipelagic layer (0-200 m), the effect of eddies on the prokaryotic community was more apparent, as indicated by the higher PA, PHA, fraction of living cells, and percentage of active cells incorporating leucine within eddies than at FF stations. Prokaryotic community composition differed also between eddy and FF stations in the epipelagic layer. In the mesopelagic layer (200-1000 m), there were also significant differences in PA and PHA between eddy and FF stations, although in general, there were no clear differences in community composition or single-cell activity. The effects on prokaryotic activity and community structure were stronger in AE than CE, decreasing with depth in both types of eddies. Overall, both types of eddies show distinct community compositions (as compared with FF in the epipelagic), and represent oceanic 'hotspots' of prokaryotic activity (in the epi- and mesopelagic realms).

Ciliated protozoa in the impact zone of the Uzhgorod treatment plant

NASA Astrophysics Data System (ADS)

Pliashechnyk, Volodimir; Danko, Yaroslav; Łagód, Grzegorz; Drewnowski, Jakub; Kuzmina, Tatiana; Babko, Roman

2018-02-01

This paper presents the results of studies on the Uzh River (Ukraine, Zakarpattia Oblast) near the effluent point of a sewage treatment plant in Uzhgorod. The samples were taken at various sites of the treatment plant along the stages of purification process, as well as in the river, at a number of different points above and below the wastewater discharge. At each of these objects, the temperature and O2 were measured. The structure of ciliate assemblage was analyzed along the stages of the treatment process in the WWTP and in the river before and after the sewage discharge. A total of 26 ciliate taxa were observed and included in the analysis. All the studied stations were considered as a continuum in which populations of protozoa spread freely according to their ecological preferences. The majority of ciliate species were encountered in each of the examined stations, but their quantitative development differed significantly, reflecting their response to the environmental conditions at the stations. The analysis of the qualitative and quantitative distribution of ciliate populations by the stations enabled to group them in respect to the peculiarities of the local conditions. The study showed that the majority of the ciliate species, typical of bioreactors, are equally common at the stations of the Uzh River below wastewater discharges. The ciliate assemblage in the oxygen gradient demonstrated a wide spectrum of ecological tolerance at the species level. These findings confirm that ciliates are very good indicators of the environmental quality, provided that detailed information about their environmental priorities is available.

Study on the three-station typical network deployments of workspace Measurement and Positioning System

NASA Astrophysics Data System (ADS)

Xiong, Zhi; Zhu, J. G.; Xue, B.; Ye, Sh. H.; Xiong, Y.

2013-10-01

As a novel network coordinate measurement system based on multi-directional positioning, workspace Measurement and Positioning System (wMPS) has outstanding advantages of good parallelism, wide measurement range and high measurement accuracy, which makes it to be the research hotspots and important development direction in the field of large-scale measurement. Since station deployment has a significant impact on the measurement range and accuracy, and also restricts the use-cost, the optimization method of station deployment was researched in this paper. Firstly, positioning error model was established. Then focusing on the small network consisted of three stations, the typical deployments and error distribution characteristics were studied. Finally, through measuring the simulated fuselage using typical deployments at the industrial spot and comparing the results with Laser Tracker, some conclusions are obtained. The comparison results show that under existing prototype conditions, I_3 typical deployment of which three stations are distributed in a straight line has an average error of 0.30 mm and the maximum error is 0.50 mm in the range of 12 m. Meanwhile, C_3 typical deployment of which three stations are uniformly distributed in the half-circumference of an circle has an average error of 0.17 mm and the maximum error is 0.28 mm. Obviously, C_3 typical deployment has a higher control effect on precision than I_3 type. The research work provides effective theoretical support for global measurement network optimization in the future work.

BROADBAND DIGITAL GEOPHYSICAL TELEMETRY SYSTEM.

USGS Publications Warehouse

Seeley, Robert L.; Daniels, Jeffrey J.

1984-01-01

A system has been developed to simultaneously sample and transmit digital data from five remote geophysical data receiver stations to a control station that processes, displays, and stores the data. A microprocessor in each remote station receives commands from the control station over a single telemetry channel.

Exposure to chemical hazards in petrol pumps stations in Ahvaz City, Iran.

PubMed

Zoleikha, Sayyahi; Mirzaei, Ramazan; Roksana, Mirkazemi

2017-01-02

The objective of this study was to assess the level of exposure to BTEX (benzene, toluene, ethylbenzene, xylenes) in petrol pump stations in Ahvaz City. Two of the biggest fuelling stations were selected randomly among total 12 fuel stations of Ahvaz City, Iran, during September 2013. Thirty air samples were taken from different positions in the fuelling stations and 15 samples were taken from the personal breathing zone of operators and of customers in fuelling stations. Measuring the ambient concentration of benzene, toluene, ethylbenzene, and xylenes was done according to the method advised by National Institute for Occupational Safety and Health (NIOSH) 1501. This study showed that the concentration of benzene was very high (compared with the Iranian occupational exposure limit [OEL] standard) in ambient air of petrol stations in Ahvaz, which is considered as a high risk to the health of workers. Controlling the level of benzene in petrol stations is necessary. A new designed petrol nozzle was proposed for this purpose.

Physical-biological coupling in the Amundsen Sea, Antarctica: Influence of physical factors on phytoplankton community structure and biomass

NASA Astrophysics Data System (ADS)

Lee, Youngju; Yang, Eun Jin; Park, Jisoo; Jung, Jinyoung; Kim, Tae Wan; Lee, SangHoon

2016-11-01

To understand the spatial distribution of phytoplankton communities in various habitats in the Amundsen Sea, western Antarctica, a field survey was conducted at 15 stations during the austral summer, from December 2013 to January 2014. Water samples were analyzed by microscopy. We found high phytoplankton abundance and biomass in the Amundsen Sea polynya (ASP). Their strong positive correlation with water temperature suggests that phytoplankton biomass accumulated in the surface layer of the stratified polynya. In the ASP, the predominant phytoplankton species was Phaeocystis antarctica, while diatoms formed a major group in the sea ice zone, especially Fragilariopsis spp., Chaetoceros spp., and Proboscia spp. Although this large diatom abundance sharply decreased just off the marginal sea ice zone, weakly silicified diatoms, due to their high buoyancy, were distributed at almost all stations on the continental shelf. Dictyocha speculum appeared to favor the area between the marginal sea ice zone and the ASP in contrast to cryptophytes and picophytoplankton, whose abundance was higher in the area between the continental shelf and the open ocean of Amundsen Sea. Several environmental factors were found to affect the spatial variation of phytoplankton species, but the community structure appeared to be controlled mainly by the seawater density related to sea-ice melting and water circulation in the Amundsen Sea.

[Radiation-induced changes in the cellular chromatin of cereal plants cultivated in the area of the Chernobyl Atomic Electric Power Station].

PubMed

Reshetnikov, V N; Lapteva, O K; Sosnovskaia, T F; Roshchenko, M V

1996-01-01

The changes in chromatin and DNA of seedling and callus tissues of cereals grown in the Chernobyl NPP zones with contamination levels of 15, 40 and 60 Ci/km2 were studied. Test samples produced by germinating and culturing seed cells of grown in contaminated areas were notable for the content of soluble polydesoxiribonucleotides, amount of DNA damages, DNA distribution over separate compartments of cell nucleus as compared to the control. Analogy between radiation-induced changes in chromatine and processes occurring in cell nucleus senescence was observed.

Project 57 Air Monitoring Report: October 1, 2013, through December 31, 2014

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mizell, Steve A.; Nikolich, George; McCurdy, Greg

On April 24, 1957, the Atomic Energy Commission (AEC, now the Department of Energy [DOE]) conducted the Project 57 safety experiment in western Emigrant Valley north east of the Nevada National Security Site (NNSS, formerly the Nevada Test Site) on lands withdrawn by the Department of Defense (DoD) for the Nevada Test and Training Range (NTTR). The test was undertaken to develop (1) a means of estimating plutonium distribution resulting from a nonnuclear detonation; (2) biomedical evaluation techniques for use in plutonium-laden environments; (3) methods of surface decontamination; and (4) instruments and field procedures for prompt estimation of alpha contaminationmore » (Shreve, 1958). Although the test did not result in the fission of nuclear materials, it did disseminate plutonium across the land surface. Following the experiment, the AEC fenced the contaminated area and returned control of the surrounding land to the DoD. Various radiological surveys have been performed in the area and in 2007, the DOE expanded the demarked contamination area by posting signs 200 to 400 feet (60 to 120 meters) outside of the original fence. Plutonium in soil is thought to attach preferentially to smaller particles. Therefore, redistribution of soil particulates by wind (dust) is the mechanism most likely to transport plutonium beyond the boundary of the Project 57 contamination area. In 2011, DRI installed two instrumentation towers to measure radiological, meteorological, and dust conditions. The monitoring activity was implemented to determine if radionuclide contamination was detectable in samples of airborne dust and characterize meteorological and environmental parameters that influence dust transport. Collected data also permits comparison of radiological conditions at the Project 57 monitoring stations to conditions observed at Community Environmental Monitoring Program (CEMP) stations around the NTTR. Biweekly samples of airborne particulates are submitted for laboratory assessment of gross alpha and gross beta radioactivity and for determination of gamma-emitting radionuclides. Annual average gross alpha values at the Project 57 monitoring stations are in the same range as the highest two values reported for the CEMP stations surrounding the NTTR. Annual average gross beta values at the Project 57 monitoring stations are slightly higher than the lowest value reported for the CEMP stations surrounding the NTTR. Gamma spectroscopy analyses on samples collected from the Project 57 stations identified only naturally occurring radionuclides. No manmade radionuclides were detected. Thermoluminescent dosimeters (TLDs) indicated that the average annual radioactivity dose at the monitoring stations is higher than the dose determined at surrounding CEMP stations but approximately half of the estimated national average dose received by the general public as a result of exposure to natural sources. The TLDs at the Project 57 monitoring stations are exposed to both natural sources (terrestrial and cosmic) and radioactive releases from the Project 57 contamination area. These comparisons show that the gross alpha, gross beta, and gamma spectroscopy levels at the Project 57 monitoring stations are similar to levels observed at the CEMP stations but that the average annual dose rate is higher than at the CEMP stations. Winds in excess of approximately 15 mph begin to generate dust movement by saltation (migration of sand at the ground surface) or direct suspension in the air. Saltated sand, PM10 (inhalable) dust, and PM2.5 (fine particulate dust) exhibit an approximately exponential increase with increasing wind speed. The greatest concentrations of dust occur for winds exceeding 20 mph. During the reporting period, winds in excess of 20 mph occurred approximately 1.6 percent of the time. Preliminary assessment of individual wind events suggests that dust generation is highly variable likely because of the influence of other meteorological and environmental parameters. Although winds sufficient to generate significant amounts of dust occur at the Project 57 site, they are infrequent and of short duration. Additionally, the potential for wind transport of dust is dependent on other parameters whose influence have not yet been assessed.« less

A survey of rapid sample return needs from Space Station Freedom and potential return systems

NASA Technical Reports Server (NTRS)

Mccandless, Ronald S.; Siegel, Bette; Charlton, Kevin

1991-01-01

Results are presented of a survey conducted among potential users of the life sciences and material sciences facilities at the Space Station Freedom (SSF) to determine the need for a special rapid sample return (RSR) mission to bring the experimental samples from the Space Station Freedom (SSF) to earth between the Space Shuttle visits. The results of the survey show that, while some experimental objectives would benefit from the RSR capability, other available cost- and mission-effective means could be used instead of the RSR proposed. Potential vehicles for transporting samples from the SSF to earth are examined in the context of the survey results.

Station Climatic Summaries, North America.

DTIC Science & Technology

1988-08-01

8603 (CB) ..................................... 371 MI IIGA ALPENA (PHELPS-COLLINS FIELD) 726390 8710 (Ce) ..................................... 372...direction APPROVED FOR PUBLIC RELEASE; DISTRIBUTION IS UNLIMITED 372 A W S Station Name: PHELPS-MOLLINS/ ALPENA KI Field Klev: 689 ft CLIMATIC BRIEF

RaPToRS Sample Delivery System

NASA Astrophysics Data System (ADS)

Henchen, Robert; Shibata, Kye; Krieger, Michael; Pogozelski, Edward; Padalino, Stephen; Glebov, Vladimir; Sangster, Craig

2010-11-01

At various labs (NIF, LLE, NRL), activated material samples are used to measure reaction properties. The Rapid Pneumatic Transport of Radioactive Samples (RaPToRS) system quickly and safely moves these radioactive samples through a closed PVC tube via airflow. The carrier travels from the reaction chamber to the control and analysis station, pneumatically braking at the outlet. A reversible multiplexer routes samples from various locations near the shot chamber to the analysis station. Also, the multiplexer allows users to remotely load unactivated samples without manually approaching the reaction chamber. All elements of the system (pneumatic drivers, flow control valves, optical position sensors, multiplexers, Geiger counters, and release gates at the analysis station) can be controlled manually or automatically using a custom LabVIEW interface. A prototype is currently operating at NRL in Washington DC. Prospective facilities for Raptors systems include LLE and NIF.

STS 129 Return Samples: Assessment of Air Quality aboard the Shuttle (STS-129) and International Space Station (ULF3)

NASA Technical Reports Server (NTRS)

James, John T.

2010-01-01

Reports on the air quality aboard the Space Shuttle (STS-129), and the International Space station (ULF3). NASA analyzed the grab sample canisters (GSCs) and the formaldehyde badges aboard both locations for carbon monoxide levels. The three surrogates: (sup 13)C-acetone, fluorobenzene, and chlorobenzene registered 109, 101, and 109% in the space shuttle and 81, 87, and 55% in the International Space Station (ISS). From these results the atmosphere in both the Space Shuttle and the International Space Station (ISS) was found to be breathable.

Availability Estimation for Facilities in Extreme Geographical Locations

NASA Technical Reports Server (NTRS)

Fischer, Gerd M.; Omotoso, Oluseun; Chen, Guangming; Evans, John W.

2012-01-01

A value added analysis for the Reliability. Availability and Maintainability of McMurdo Ground Station was developed, which will be a useful tool for system managers in sparing, maintenance planning and determining vital performance metrics needed for readiness assessment of the upgrades to the McMurdo System. Output of this study can also be used as inputs and recommendations for the application of Reliability Centered Maintenance (RCM) for the system. ReliaSoft's BlockSim. a commercial Reliability Analysis software package, has been used to model the availability of the system upgrade to the National Aeronautics and Space Administration (NASA) Near Earth Network (NEN) Ground Station at McMurdo Station in the Antarctica. The logistics challenges due to the closure of access to McMurdo Station during the Antarctic winter was modeled using a weighted composite of four Weibull distributions. one of the possible choices for statistical distributions throughout the software program and usually used to account for failure rates of components supplied by different manufacturers. The inaccessibility of the antenna site on a hill outside McMurdo Station throughout one year due to severe weather was modeled with a Weibull distribution for the repair crew availability. The Weibull distribution is based on an analysis of the available weather data for the antenna site for 2007 in combination with the rules for travel restrictions due to severe weather imposed by the administrating agency, the National Science Foundation (NSF). The simulations resulted in an upper bound for the system availability and allowed for identification of components that would improve availability based on a higher on-site spare count than initially planned.

Water-quality trend analysis and sampling design for the Devils Lake Basin, North Dakota, January 1965 through September 2003

USGS Publications Warehouse

Ryberg, Karen R.; Vecchia, Aldo V.

2006-01-01

This report presents the results of a study conducted by the U.S. Geological Survey, in cooperation with the North Dakota State Water Commission, the Devils Lake Basin Joint Water Resource Board, and the Red River Joint Water Resource District, to analyze historical water-quality trends in three dissolved major ions, three nutrients, and one dissolved trace element for eight stations in the Devils Lake Basin in North Dakota and to develop an efficient sampling design to monitor the future trends. A multiple-regression model was used to detect and remove streamflow-related variability in constituent concentrations. To separate the natural variability in concentration as a result of variability in streamflow from the variability in concentration as a result of other factors, the base-10 logarithm of daily streamflow was divided into four components-a 5-year streamflow anomaly, an annual streamflow anomaly, a seasonal streamflow anomaly, and a daily streamflow anomaly. The constituent concentrations then were adjusted for streamflow-related variability by removing the 5-year, annual, seasonal, and daily variability. Constituents used for the water-quality trend analysis were evaluated for a step trend to examine the effect of Channel A on water quality in the basin and a linear trend to detect gradual changes with time from January 1980 through September 2003. The fitted upward linear trends for dissolved calcium concentrations during 1980-2003 for two stations were significant. The fitted step trends for dissolved sulfate concentrations for three stations were positive and similar in magnitude. Of the three upward trends, one was significant. The fitted step trends for dissolved chloride concentrations were positive but insignificant. The fitted linear trends for the upstream stations were small and insignificant, but three of the downward trends that occurred during 1980-2003 for the remaining stations were significant. The fitted upward linear trends for dissolved nitrite plus nitrate as nitrogen concentrations during 1987-2003 for two stations were significant. However, concentrations during recent years appear to be lower than those for the 1970s and early 1980s but higher than those for the late 1980s and early 1990s. The fitted downward linear trend for dissolved ammonia concentrations for one station was significant. The fitted linear trends for total phosphorus concentrations for two stations were significant. Upward trends for total phosphorus concentrations occurred from the late 1980s to 2003 for most stations, but a small and insignificant downward trend occurred for one station. Continued monitoring will be needed to determine if the recent trend toward higher dissolved nitrite plus nitrate as nitrogen and total phosphorus concentrations continues in the future. For continued monitoring of water-quality trends in the upper Devils Lake Basin, an efficient sampling design consists of five major-ion, nutrient, and trace-element samples per year at three existing stream stations and at three existing lake stations. This sampling design requires the collection of 15 stream samples and 15 lake samples per year rather than 16 stream samples and 20 lake samples per year as in the 1992-2003 program. Thus, the design would result in a program that is less costly and more efficient than the 1992-2003 program but that still would provide the data needed to monitor water-quality trends in the Devils Lake Basin.

Integration of Reference Frames Using VLBI

NASA Technical Reports Server (NTRS)

Ma, Chopo; Smith, David E. (Technical Monitor)

2001-01-01

Very Long Baseline Interferometry (VLBI) has the unique potential to integrate the terrestrial and celestial reference frames through simultaneous estimation of positions and velocities of approx. 40 active VLBI stations and a similar number of stations/sites with sufficient historical data, the position and position stability of approx. 150 well-observed extragalactic radio sources and another approx. 500 sources distributed fairly uniformly on the sky, and the time series of the five parameters that specify the relative orientation of the two frames. The full realization of this potential is limited by a number of factors including the temporal and spatial distribution of the stations, uneven distribution of observations over the sources and the sky, variations in source structure, modeling of the solid/fluid Earth and troposphere, logistical restrictions on the daily observing network size, and differing strategies for optimizing analysis for TRF, for CRF and for EOP. The current status of separately optimized and integrated VLBI analysis will be discussed.

Precision time distribution within a deep space communications complex

NASA Technical Reports Server (NTRS)

Curtright, J. B.

1972-01-01

The Precision Time Distribution System (PTDS) at the Golstone Deep Space Communications Complex is a practical application of existing technology to the solution of a local problem. The problem was to synchronize four station timing systems to a master source with a relative accuracy consistently and significantly better than 10 microseconds. The solution involved combining a precision timing source, an automatic error detection assembly and a microwave distribution network into an operational system. Upon activation of the completed PTDS two years ago, synchronization accuracy at Goldstone (two station relative) was improved by an order of magnitude. It is felt that the validation of the PTDS mechanization is now completed. Other facilities which have site dispersion and synchronization accuracy requirements similar to Goldstone may find the PTDS mechanization useful in solving their problem. At present, the two station relative synchronization accuracy at Goldstone is better than one microsecond.

Environmental control/life support system for Space Station

NASA Technical Reports Server (NTRS)

Miller, C. W.; Heppner, D. B.; Schubert, F. H.; Dahlhausen, M. J.

1986-01-01

The functional, operational, and design load requirements for the Environmental Control/Life Support System (ECLSS) are described. The ECLSS is divided into two groups: (1) an atmosphere management group and (2) a water and waste management group. The interaction between the ECLSS and the Space Station Habitability System is examined. The cruciform baseline station design, the delta and big T module configuration, and the reference Space Station configuration are evaluated in terms of ECLSS requirements. The distribution of ECLSS equipment in a reference Space Station configuration is studied as a function of initial operating conditions and growth orbit capabilities. The benefits of water electrolysis as a Space Station utility are considered.

Determination of baseline periods of record for selected streamflow-gaging stations in and near Oklahoma for use in modeling applications

USGS Publications Warehouse

Esralew, Rachel A.

2010-01-01

Use of historical streamflow data from a least-altered period of record can be used in calibration of various modeling applications that are used to characterize least-altered flow and predict the effects of proposed streamflow alteration. This information can be used to enhance water-resources planning. A baseline period of record was determined for selected streamflow-gaging stations that can be used as a calibration dataset for modeling applications. The baseline period of record was defined as a period that is least-altered by anthropogenic activity and has sufficient streamflow record length to represent extreme climate variability. Streamflow data from 171 stations in and near Oklahoma with a minimum of 10 complete water years of daily streamflow record through water year 2007 and drainage areas that were less than 2,500 square miles were considered for use in the baseline period analysis. The first step to determine the least-altered period of record was to evaluate station information by using previous publications, historical station record notes, and information gathered from oral and written communication with hydrographers familiar with selected stations. The second step was to indentify stations that had substantial effects from upstream regulation by evaluating the location and extent of dams in the drainage basin. The third step was (a) the analysis of annual hydrographs and included visual hydrograph analysis for selected stations with 20 or more years of streamflow record, (b) analysis of covariance of double-mass curves, and (c) Kendall's tau trend analysis to detect statistically significant trends in base flow, runoff, total flow, and base-flow index related to anthropogenic activity for selected stations with 15 or more years of streamflow record. A preliminary least-altered period of record for each stream was identified by removing the period of streamflow record when streams were substantially affected by anthropogenic activity. After streamflow record was removed from designation as a least-altered period, stations that did not have at least 10 years of remaining continuous streamflow record were considered to have an insufficient baseline period for modeling applications. An optimum minimum period of record was determined for each of the least-altered periods for each station to ensure a sufficient streamflow record length to provide a representative sample of annual climate variability. An optimum minimum period of 10 years or more was evaluated by analyzing the variability of annual precipitation for selected 5-, 10-, 15-, 25-, and 35-year periods for each of 20 climate divisions that contained stations used in the baseline period analysis. The distribution of annual precipitation was compared for each consecutive overlapping 5-year period to the period 1925-2007 by using a Wilcoxon rank-sum test. The least-altered period of record for stations was also compared to the period 1925-2007 by using a Wilcoxon rank-sum test. The results of this analysis were used to determine how many years of annual precipitation data were needed for the selected period to be statistically similar to the distribution of annual precipitation data for a long-term period, 1925-2007. Minimum optimum periods ranged from 10 to 35 years and varied by climate division. A final baseline period was determined for 111 stations that had a baseline period of at least 10 years of continuous streamflow record after the record-elimination process. A suitable baseline period of record for use in modeling applications could not be identified for 58 of the initial 171 stations because of substantial anthropogenic alteration of the stream or drainage basin and for 2 stations because the least-altered period of record was not representative of annual climate variability. The baseline period for each station was rated ?excellent?, ?good?, ?fair?, ?poor?, or ?no baseline period.? This rating was based on a qualitative evaluation of t

Longitudinal changes in microbial planktonic communities of a French river in relation to pesticide and nutrient inputs.

PubMed

Pesce, Stéphane; Fajon, Céline; Bardot, Corinne; Bonnemoy, Frédérique; Portelli, Christophe; Bohatier, Jacques

2008-02-18

To determine the effects of anthropic activities on river planktonic microbial populations, monthly water samples were collected for 11 months from two sampling sites characterized by differing nutrient and pesticide levels. The difference in trophic level between the two stations was particularly pronounced from May to November. Total pesticide concentrations were notably higher at the downstream station from April to October with a clear predominance of herbicide residues, especially the glyphosate metabolite aminomethylphosphonic acid (AMPA). From spring, algal biomass and density were favored by the high orthophosphate concentrations recorded at the downstream location. However, isolated drops in algal biomass were recorded at this sampling station, suggesting an adverse effect of herbicides on algal communities. No major difference was observed in bacterial heterotrophic production, density, or activity (CTC reduction) between the two sampling stations. No major variation was detected using the fluorescent in situ hybridization (FISH) method, but shifts in bacterial community composition were recorded by PCR-TTGE analysis at the downstream station following high nutrient and pesticide inputs. However, outside the main anthropic pollution period, the water's chemical properties and planktonic microbial communities were very similar at the two sampling sites, suggesting a high recovery potential for this lotic system.

Studies on Anthropogenic Impact on Water Quality in Hilo (Hawaii) Bay and Mapping the Study Stations Using Geospatial Technologies

NASA Astrophysics Data System (ADS)

Cartier, A. J.; Williams, M. S.; Adolf, J.; Sriharan, S.

2015-12-01

Hilo Bay has uncharacteristically brown waters compared to other waters found in Hawai'i. The majority of the freshwater entering Hilo Bay is from storm and surface water runoff. The anthropogenic impact on water quality at Hilo Bay is due to sediment entrance, cesspools (Bacteria), and invasive species (Albizia). This poster presentation will focus on the water quality and phytoplankton collected on a weekly basis at a buoy positioned one meter from the shore of Hilo Bay, preserving the phytoplankton intact, concentrating and dehydrating the sample with ethanol, and viewing the phytoplankton with a scanning electron microscope (Hitachi S-3400NII). The GPS (Global Positioning System) points were collected at the sampling stations. Three transects on three separate dates were performed in Hilo Bay with salinity, percent dissolved oxygen, turbidity, secchi depth, temperature, and chlorophyll fluorescence data collected at each sampling station. A consistent trend observed in all transects was as distance from the river increased turbidity decreased and salinity increased. The GPS data on June 30, 2015 showed a major correlation between stations and their distance from shore. There is a decrease in the turbidity but not the temperature for these stations. The GPS points collected on July 7, 2015 at thirteen stations starting with station one being at the shore to the water, showed that the salinity concentration fluctuate noticeably at the first 6 stations. As we proceed further away from the shore, the salinity concentration increases from stations seven through thirteen. The water temperature shows little variation throughout the thirteen stations. The turbidity level was high at the shore and shows a noticeable drop at station thirteen.

Changing times at the Rocky Mountain Forest & Range Experiment Station: Station history from 1976 to 1997

Treesearch

R. H. Hamre

2005-01-01

Changing Times includes a review of early Station history, touches on changing societal perspectives and how things are now done differently, how the Station has changed physically and organizationally, technology transfer, a sampling of major characters, how some Station research has been applied, and a timeline of significant and/or interesting events. It includes...

Mercury in Precipitation in Indiana, January 2001-December 2003

USGS Publications Warehouse

Risch, Martin R.

2007-01-01

Total mercury deposition that was more than 10 percent of the mean annual deposition (1,262 ng/m2 ) was recorded in 11 of 551 weekly samples from the study period. These samples contained approximately 3 inches or more of rain and most were collected in spring and summer 2003. The highest deposition (2,456 ng/m2 in a sample from Roush Lake) was 15.7 percent of the annual deposition at that station and approximately 10 times the mean weekly deposition for Indiana. High deposition recorded in three weekly samples at Clifty Falls contributed 31 percent of the annual deposition at that station in 2003. Weekly samples with high mercury deposition may help to explain the differences in annual mercury deposition among the four monitoring stations in Indiana.

Horizontal and Vertical Distributions of Transparent Exopolymer Particles (TEP) in the NW Mediterranean Sea Are Linked to Chlorophyll a and O2 Variability

PubMed Central

Ortega-Retuerta, Eva; Sala, Maria M.; Borrull, Encarna; Mestre, Mireia; Aparicio, Fran L.; Gallisai, Rachele; Antequera, Carolina; Marrasé, Cèlia; Peters, Francesc; Simó, Rafel; Gasol, Josep M.

2017-01-01

Transparent Exopolymer Particles (TEP) are relevant in particle and carbon fluxes in the ocean, and have economic impact in the desalination industry affecting reverse osmosis membrane fouling. However, general models of their occurrence and dynamics are not yet possible because of the poorly known co-variations with other physical and biological variables. Here, we describe TEP distributions in the NW Mediterranean Sea during late spring 2012, along perpendicular and parallel transects to the Catalan coast. The stations in the parallel transect were sampled at the surface, while the stations in the perpendicular transect were sampled from the surface to the bathypelagic, including the bottom nepheloid layers. We also followed the short-term TEP dynamics along a 2-day cycle in offshore waters. TEP concentrations in the area ranged from 4.9 to 122.8 and averaged 31.4 ± 12.0 μg XG eq L−1. The distribution of TEP measured in transects parallel to the Catalan Coast correlated those of chlorophyll a (Chla) in May but not in June, when higher TEP-values with respect to Chla were observed. TEP horizontal variability in epipelagic waters from the coast to the open sea also correlated to that of Chla, O2 (that we interpret as a proxy of primary production) and bacterial production (BP). In contrast, the TEP vertical distributions in epipelagic waters were uncoupled from those of Chla, as TEP maxima were located above the deep chlorophyll maxima. The vertical distribution of TEP in the epipelagic zone was correlated with O2 and BP, suggesting combined phytoplankton (through primary production) and bacterial (through carbon reprocessing) TEP sources. However, no clear temporal patterns arose during the 2-day cycle. In meso- and bathypelagic waters, where phytoplanktonic sources are minor, TEP concentrations (10.1 ± 4.3 μg XG eq l−1) were half those in the epipelagic, but we observed relative TEP increments coinciding with the presence of nepheloid layers. These TEP increases were not paralleled by increases in particulate organic carbon, indicating that TEP are likely to act as aggregating agents of the mostly inorganic particles present in these bottom nepheloid layers. PMID:28197126

Using Python to generate AHPS-based precipitation simulations over CONUS using Amazon distributed computing

NASA Astrophysics Data System (ADS)

Machalek, P.; Kim, S. M.; Berry, R. D.; Liang, A.; Small, T.; Brevdo, E.; Kuznetsova, A.

2012-12-01

We describe how the Climate Corporation uses Python and Clojure, a language impleneted on top of Java, to generate climatological forecasts for precipitation based on the Advanced Hydrologic Prediction Service (AHPS) radar based daily precipitation measurements. A 2-year-long forecasts is generated on each of the ~650,000 CONUS land based 4-km AHPS grids by constructing 10,000 ensembles sampled from a 30-year reconstructed AHPS history for each grid. The spatial and temporal correlations between neighboring AHPS grids and the sampling of the analogues are handled by Python. The parallelization for all the 650,000 CONUS stations is further achieved by utilizing the MAP-REDUCE framework (http://code.google.com/edu/parallel/mapreduce-tutorial.html). Each full scale computational run requires hundreds of nodes with up to 8 processors each on the Amazon Elastic MapReduce (http://aws.amazon.com/elasticmapreduce/) distributed computing service resulting in 3 terabyte datasets. We further describe how we have productionalized a monthly run of the simulations process at full scale of the 4km AHPS grids and how the resultant terabyte sized datasets are handled.

Occurrence, distribution, and sources of emerging organic contaminants in tropical coastal sediments of anthropogenically impacted Klang River estuary, Malaysia.

PubMed

Omar, Tuan Fauzan Tuan; Aris, Ahmad Zaharin; Yusoff, Fatimah Md; Mustafa, Shuhaimi

2018-06-01

This baseline assessment reports on the occurrence, distribution, and sources of emerging organic contaminants (EOCs) in tropical coastal sediments of anthropogenically impacted Klang River estuary, Malaysia. Bisphenol A was the highest concentration detected at 16.84 ng g -1 dry weight, followed by diclofenac (13.88 ng g -1 dry weight) and E1 (12.47 ng g -1 dry weight). Five compounds, namely, amoxicillin, progesterone, diazinon, bisphenol A, and E1, were found in all sampling stations assessed, and other compounds such as primidone, diclofenac, testosterone, E2, and EE2 were ubiquitously present in sediment samples, with percentage of detection range from 89.04% to 98.38%. Organic carbon content and pH were the important factors controlling the fate of targeted compounds in the tropical estuarine sediment. On the basis of the literature from other studies, the sources of EOCs are thought to be from wastewater treatment plants, domestic/medical waste discharge, livestock activities, industrial waste discharge, and agricultural activities. Copyright © 2018 Elsevier Ltd. All rights reserved.

Joint maximum-likelihood magnitudes of presumed underground nuclear test explosions

NASA Astrophysics Data System (ADS)

Peacock, Sheila; Douglas, Alan; Bowers, David

2017-08-01

Body-wave magnitudes (mb) of 606 seismic disturbances caused by presumed underground nuclear test explosions at specific test sites between 1964 and 1996 have been derived from station amplitudes collected by the International Seismological Centre (ISC), by a joint inversion for mb and station-specific magnitude corrections. A maximum-likelihood method was used to reduce the upward bias of network mean magnitudes caused by data censoring, where arrivals at stations that do not report arrivals are assumed to be hidden by the ambient noise at the time. Threshold noise levels at each station were derived from the ISC amplitudes using the method of Kelly and Lacoss, which fits to the observed magnitude-frequency distribution a Gutenberg-Richter exponential decay truncated at low magnitudes by an error function representing the low-magnitude threshold of the station. The joint maximum-likelihood inversion is applied to arrivals from the sites: Semipalatinsk (Kazakhstan) and Novaya Zemlya, former Soviet Union; Singer (Lop Nor), China; Mururoa and Fangataufa, French Polynesia; and Nevada, USA. At sites where eight or more arrivals could be used to derive magnitudes and station terms for 25 or more explosions (Nevada, Semipalatinsk and Mururoa), the resulting magnitudes and station terms were fixed and a second inversion carried out to derive magnitudes for additional explosions with three or more arrivals. 93 more magnitudes were thus derived. During processing for station thresholds, many stations were rejected for sparsity of data, obvious errors in reported amplitude, or great departure of the reported amplitude-frequency distribution from the expected left-truncated exponential decay. Abrupt changes in monthly mean amplitude at a station apparently coincide with changes in recording equipment and/or analysis method at the station.

Review on Water Distribution of Cooling Tower in Power Station

NASA Astrophysics Data System (ADS)

Huichao, Zhang; Lei, Fang; Hao, Guang; Ying, Niu

2018-04-01

As the energy sources situation is becoming more and more severe, the importance of energy conservation and emissions reduction gets clearer. Since the optimization of water distribution system of cooling tower in power station can save a great amount of energy, the research of water distribution system gets more attention nowadays. This paper summarizes the development process of counter-flow type natural draft wet cooling tower and the water distribution system, and introduces the related domestic and international research situation. Combining the current situation, we come to the conclusion about the advantages and disadvantages of the several major water distribution modes, and analyze the problems of the existing water distribution ways in engineering application, furthermore, we put forward the direction of water distribution mode development on the basis knowledge of water distribution of cooling tower. Due to the water system can hardly be optimized again when it’s built, choosing an appropriate water distribution mode according to actual condition seems to be more significant.

Weekend Commercial Children's Television, 1975. A Study of Programming and Advertising to Children on Five Boston Stations.

ERIC Educational Resources Information Center

Barcus, F. Earle

Some 25-1/2 hours of Boston commercial television for children were monitored on a Saturday and Sunday in April 1975. The monitoring covered three network affiliated stations and two independent UHF stations. Monitoring, coding, and editing provided much statistical data, which was analyzed to yield findings in the areas of distribution of…

An innovative approach for distributed and integrated resources planning for the Space Station Freedom

NASA Technical Reports Server (NTRS)

Hornstein, Rhoda S.; Shinkle, Gerald L.; Weiler, Jerry D.; Willoughby, John K.

1990-01-01

This paper presents a planning approach to the Space Station Freedom program which takes into account the widely distributed nature of that program. The program management structure is organized into three major levels: a strategic level, a tactical level, and an execution level. For each level, resource availabilities are determined, the resources are distributed, schedules are built independently within the resource limits, the schedules are integrated into a single schedule, and conflicts are resolved by negotiating requirements and/or relaxing contraints. This approach distributes resources to multiple planning entities in such a way that when the multiple plans are collected, they fit together with minimal modification. The up-front distribution is planned in such a way and to a sufficient degree that a fit is virtually assured.

Water quality, organic chemistry of sediment, and biological conditions of streams near an abandoned wood-preserving plant site at Jackson, Tennessee

USGS Publications Warehouse

Bradfield, A.D.; Flexner, N.M.; Webster, D.A.

1993-01-01

An investigation of water quality, organic sediment chemistry, and biological conditions of streams near an abandoned wood-preserving plant site at Jackson, Tennessee, was conducted during December 1990. The study was designed to assess the extent of possible contamination of water and biota in the streams from creosote-related discharge originating at this Superfund site. Central Creek, adjacent to the plant, had degraded water quality and biological conditions. Water samples from the most downstream station on Central Creek contained 30 micrograms per liter of pentachlorophenol, which exceeds the State's criterion maximum concentrations of 9 micrograms per liter for fish and aquatic life. Bottom-sediment samples from stations on Central Creek contained concentrations of acenaphthene, napthalene, and phenanthrene ranging from 1,400 to 2,500 micrograms per kilogram. Chronic or acute toxicity resulted during laboratory experiments using test organisms exposed to creosote-related contaminants. Sediment elutriate samples from Central Creek caused slightly to highly toxic effects on Ceriodaphnia dubia. Pimephales promelas, and Photobacterium phosphoreum. Fish-tissue samples from this station contained concentrations of naphthalene. dibenzofuran, fluorene, and phenanthrene ranging from 1.5 to 3.9 micrograms per kilogram Blue-green algae at this station represented about 79 percent of the organisms counted, whereas diatoms accounted for only 11 percent. Benthic invertebrate and fish samples from Central Creek had low diversity and density. Sediment samples from a station on the South Fork Forked Deer River downstream from its confluence with Central Creek contained concentrations of acenaphthene, anthracene, chrysene, fluoranthene, fluorene, pyrere, and phenanthrene ranging from 2,800 to 69,000 micrograms per kilogram. Sediment elutriate samples using water as elutriate from this station contained concentrations of extractable organic compounds ranging from an estimated 43 to 420 micrograms per liter. Sediment elutriate samples were toxic to Ceriodaphnia dubta, Pimephales promelas, Photobacterium phosphoreum, and Salenastrum capricornulum.

Microbial distribution in the Environmental Control and Life Support System water recovery test conducted at NASA, MSFC

NASA Technical Reports Server (NTRS)

Gauthier, J. J.; Roman, M. C.; Kilgore, B. A.; Huff, T. L.; Obenhuber, D. C.; Terrell, D. W.; Wilson, M. E.; Jackson, N. E.

1991-01-01

NASA/MSFC is developing a physical/chemical treatment system to reclaim wastewater for reuse on Space Station Freedom (SSF). Integrated testing of hygiene and potable water subsystems assessed the capability to reclaim water to SSF specifications. The test was conducted from May through July 1990 with a total of 47 days of system test operation. Water samples were analyzed using standard cultural methods employing membrane filtration and spread plate techniques and epifluorescence microscopy. Fatty acid methyl ester and biochemical profiles were used for microbial identification. Analysis of waste and product water produced by the subsystems demonstrated the effective reduction of viable microbial populations greater than 8.0E + 06 colony forming units (CFU) per 100 mL to an average of 5 CFU/100 mL prior to distribution into storage tanks.

Effects of urbanization on stream water quality in the city of Atlanta, Georgia, USA

USGS Publications Warehouse

Peters, N.E.

2009-01-01

A long-term stream water quality monitoring network was established in the city of Atlanta, Georgia during 2003 to assess baseline water quality conditions and the effects of urbanization on stream water quality. Routine hydrologically based manual stream sampling, including several concurrent manual point and equal width increment sampling, was conducted ???12 times annually at 21 stations, with drainage areas ranging from 3.7 to 232 km2. Eleven of the stations are real-time (RT) stations having continuous measures of stream stage/ discharge, pH, dissolved oxygen, specific conductance, water temperature and turbidity, and automatic samplers for stormwater collection. Samples were analyzed for field parameters, and a broad suite of water quality and sediment-related constituents. Field parameters and concentrations of major ions, metals, nutrient species and coliform bacteria among stations were evaluated and with respect to watershed characteristics and plausible sources from 2003 through September 2007. Most constituent concentrations are much higher than nearby reference streams. Concentrations are statistically different among stations for several constituents, despite high variability both within and among stations. Routine manual sampling, automatic sampling during stormflows and RT water quality monitoring provided sufficient information about urban stream water quality variability to evaluate causes of water quality differences among streams. Fecal coliform bacteria concentrations of most samples exceeded Georgia's water quality standard for any water-usage class. High chloride concentrations occur at three stations and are hypothesized to be associated with discharges of chlorinated combined sewer overflows, drainage of swimming pool(s) and dissolution and transport during rainstorms of CaCl2, a deicing salt applied to roads during winter storms. One stream was affected by dissolution and transport of ammonium alum [NH4Al(SO4)2] from an alum-manufacturing plant; streamwater has low pH (<5), low alkalinity and high metals concentrations. Several trace metals exceed acute and chronic water quality standards and high concentrations are attributed to washoff from impervious surfaces.