Setting analyst: A practical harvest planning technique
Olivier R.M. Halleux; W. Dale Greene
2001-01-01
Setting Analyst is an ArcView extension that facilitates practical harvest planning for ground-based systems. By modeling the travel patterns of ground-based machines, it compares different harvesting settings based on projected average skidding distance, logging costs, and site disturbance levels. Setting Analyst uses information commonly available to consulting...
NASA Technical Reports Server (NTRS)
Urban, David
2013-01-01
Ground based microgravity facilities are an important proving ground for space experiments, ground-based research and space hardware risk mitigation. An overview of existing platforms will be discussed with an emphasis on drop tower capabilities. The potential for extension to partial gravity conditions will be discussed. Input will be solicited from attendees for their potential to use drop towers in the future and the need for enhanced capabilities (e.g. partial gravity)
User interface for ground-water modeling: Arcview extension
Tsou, Ming‐shu; Whittemore, Donald O.
2001-01-01
Numerical simulation for ground-water modeling often involves handling large input and output data sets. A geographic information system (GIS) provides an integrated platform to manage, analyze, and display disparate data and can greatly facilitate modeling efforts in data compilation, model calibration, and display of model parameters and results. Furthermore, GIS can be used to generate information for decision making through spatial overlay and processing of model results. Arc View is the most widely used Windows-based GIS software that provides a robust user-friendly interface to facilitate data handling and display. An extension is an add-on program to Arc View that provides additional specialized functions. An Arc View interface for the ground-water flow and transport models MODFLOW and MT3D was built as an extension for facilitating modeling. The extension includes preprocessing of spatially distributed (point, line, and polygon) data for model input and postprocessing of model output. An object database is used for linking user dialogs and model input files. The Arc View interface utilizes the capabilities of the 3D Analyst extension. Models can be automatically calibrated through the Arc View interface by external linking to such programs as PEST. The efficient pre- and postprocessing capabilities and calibration link were demonstrated for ground-water modeling in southwest Kansas.
Manned geosynchronous mission requirements and systems analysis study extension
NASA Technical Reports Server (NTRS)
1981-01-01
Turnaround requirements for the manned orbital transfer vehicle (MOTV) baseline and alternate concepts with and without a space operations center (SOC) are defined. Manned orbital transfer vehicle maintenance, refurbishment, resupply, and refueling are considered as well as the most effective combination of ground based and space based turnaround activities. Ground and flight operations requirements for abort are identified as well as low cost approaches to space and ground operations through maintenance and missions sensitivity studies. The recommended turnaround mix shows that space basing MOTV at SOC with periodic return to ground for overhaul results in minimum recurring costs. A pressurized hangar at SOC reduces labor costs by approximately 50%.
Flight test experience and controlled impact of a large, four-engine, remotely piloted airplane
NASA Technical Reports Server (NTRS)
Kempel, R. W.; Horton, T. W.
1985-01-01
A controlled impact demonstration (CID) program using a large, four engine, remotely piloted transport airplane was conducted. Closed loop primary flight control was performed from a ground based cockpit and digital computer in conjunction with an up/down telemetry link. Uplink commands were received aboard the airplane and transferred through uplink interface systems to a highly modified Bendix PB-20D autopilot. Both proportional and discrete commands were generated by the ground pilot. Prior to flight tests, extensive simulation was conducted during the development of ground based digital control laws. The control laws included primary control, secondary control, and racetrack and final approach guidance. Extensive ground checks were performed on all remotely piloted systems. However, manned flight tests were the primary method of verification and validation of control law concepts developed from simulation. The design, development, and flight testing of control laws and the systems required to accomplish the remotely piloted mission are discussed.
NASA Technical Reports Server (NTRS)
Gnanalingam, S.; Kane, J. A.
1973-01-01
An extensive set of ground-based measurements of the diurnal variation of medium frequency radio wave adsorption and virtual height is analyzed in terms of current understanding of the D- and lower E-region ion production and loss process. When this is done a gross discrepancy arises, the source of which is not known.
Zhanqing Li; Feng Niu; Kwon-Ho Lee; Jinyuan Xin; Wei Min Hao; Bryce L. Nordgren; Yuesi Wang; Pucai Wang
2007-01-01
The Moderate Resolution Imaging Spectroradiometer (MODIS) currently provides the most extensive aerosol retrievals on a global basis, but validation is limited to a small number of ground stations. This study presents a comprehensive evaluation of Collection 4 and 5 MODIS aerosol products using ground measurements from the Chinese Sun Hazemeter Network (CSHNET). The...
Flight test experience and controlled impact of a remotely piloted jet transport aircraft
NASA Technical Reports Server (NTRS)
Horton, Timothy W.; Kempel, Robert W.
1988-01-01
The Dryden Flight Research Center Facility of NASA Ames Research Center (Ames-Dryden) and the FAA conducted the controlled impact demonstration (CID) program using a large, four-engine, remotely piloted jet transport airplane. Closed-loop primary flight was controlled through the existing onboard PB-20D autopilot which had been modified for the CID program. Uplink commands were sent from a ground-based cockpit and digital computer in conjunction with an up-down telemetry link. These uplink commands were received aboard the airplane and transferred through uplink interface systems to the modified PB-20D autopilot. Both proportional and discrete commands were produced by the ground system. Prior to flight tests, extensive simulation was conducted during the development of ground-based digital control laws. The control laws included primary control, secondary control, and racetrack and final approach guidance. Extensive ground checks were performed on all remotely piloted systems; however, piloted flight tests were the primary method and validation of control law concepts developed from simulation. The design, development, and flight testing of control laws and systems required to accomplish the remotely piloted mission are discussed.
Soil moisture mapping by ground and airborne microwave radiometry
NASA Technical Reports Server (NTRS)
Poe, G.; Edgerton, A. T.
1972-01-01
Extensive ground-based and airborne investigations were undertaken in conjunction with laboratory dielectric measurements of soils and analytical modeling. Radiometric measurements were made in the vicinity of Phoenix, Arizona at observational wavelengths ranging from 0.81 to 21 cm. Ground experiments were conducted with a microwave field laboratory and airborne measurements were obtained from a CV-990 aircraft. Research activities were focused on establishing basic relationships between microwave emission and the distribution of moisture.
76 FR 35344 - Airworthiness Directives; Costruzioni Aeronautiche Tecnam srl Model P2006T Airplanes
Federal Register 2010, 2011, 2012, 2013, 2014
2011-06-17
... retraction/extension ground checks performed on the P2006T, a loose Seeger ring was found on the nose landing... specified products. The MCAI states: During Landing Gear retraction/extension ground checks performed on the... airworthiness information (MCAI) states: During Landing Gear retraction/extension ground checks performed on the...
Comparison of High-Frequency Solar Irradiance: Ground Measured vs. Satellite-Derived
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lave, Matthew; Weekley, Andrew
2016-11-21
High-frequency solar variability is an important to grid integration studies, but ground measurements are scarce. The high resolution irradiance algorithm (HRIA) has the ability to produce 4-sceond resolution global horizontal irradiance (GHI) samples, at locations across North America. However, the HRIA has not been extensively validated. In this work, we evaluate the HRIA against a database of 10 high-frequency ground-based measurements of irradiance. The evaluation focuses on variability-based metrics. This results in a greater understanding of the errors in the HRIA as well as suggestions for improvement to the HRIA.
Ziegler, Tom; Krykunov, Mykhaylo; Autschbach, Jochen
2014-09-09
The random phase approximation (RPA) equation of adiabatic time dependent density functional ground state response theory (ATDDFT) has been used extensively in studies of excited states. It extracts information about excited states from frequency dependent ground state response properties and avoids, thus, in an elegant way, direct Kohn-Sham calculations on excited states in accordance with the status of DFT as a ground state theory. Thus, excitation energies can be found as resonance poles of frequency dependent ground state polarizability from the eigenvalues of the RPA equation. ATDDFT is approximate in that it makes use of a frequency independent energy kernel derived from the ground state functional. It is shown in this study that one can derive the RPA equation of ATDDFT from a purely variational approach in which stationary states above the ground state are located using our constricted variational DFT (CV-DFT) method and the ground state functional. Thus, locating stationary states above the ground state due to one-electron excitations with a ground state functional is completely equivalent to solving the RPA equation of TDDFT employing the same functional. The present study is an extension of a previous work in which we demonstrated the equivalence between ATDDFT and CV-DFT within the Tamm-Dancoff approximation.
76 FR 18964 - Airworthiness Directives; Costruzioni Aeronautiche Tecnam srl Model P2006T Airplanes
Federal Register 2010, 2011, 2012, 2013, 2014
2011-04-06
... Landing Gear retraction/extension ground checks performed on the P2006T, a loose Seeger ring was found on... condition for the specified products. The MCAI states: During Landing Gear retraction/extension ground... retraction/extension ground checks performed on the P2006T, a loose Seeger ring was found on the nose landing...
Ground System Architectures Workshop GMSEC SERVICES SUITE (GSS): an Agile Development Story
NASA Technical Reports Server (NTRS)
Ly, Vuong
2017-01-01
The GMSEC (Goddard Mission Services Evolution Center) Services Suite (GSS) is a collection of tools and software services along with a robust customizable web-based portal that enables the user to capture, monitor, report, and analyze system-wide GMSEC data. Given our plug-and-play architecture and the needs for rapid system development, we opted to follow the Scrum Agile Methodology for software development. Being one of the first few projects to implement the Agile methodology at NASA GSFC, in this presentation we will present our approaches, tools, successes, and challenges in implementing this methodology. The GMSEC architecture provides a scalable, extensible ground and flight system for existing and future missions. GMSEC comes with a robust Application Programming Interface (GMSEC API) and a core set of Java-based GMSEC components that facilitate the development of a GMSEC-based ground system. Over the past few years, we have seen an upbeat in the number of customers who are moving from a native desktop application environment to a web based environment particularly for data monitoring and analysis. We also see a need to provide separation of the business logic from the GUI display for our Java-based components and also to consolidate all the GUI displays into one interface. This combination of separation and consolidation brings immediate value to a GMSEC-based ground system through increased ease of data access via a uniform interface, built-in security measures, centralized configuration management, and ease of feature extensibility.
Behavior of stem cells under outer-space microgravity and ground-based microgravity simulation.
Zhang, Cui; Li, Liang; Chen, Jianling; Wang, Jinfu
2015-06-01
With rapid development of space engineering, research on life sciences in space is being conducted extensively, especially cellular and molecular studies on space medicine. Stem cells, undifferentiated cells that can differentiate into specialized cells, are considered a key resource for regenerative medicine. Research on stem cells under conditions of microgravity during a space flight or a ground-based simulation has generated several excellent findings. To help readers understand the effects of outer space and ground-based simulation conditions on stem cells, we reviewed recent studies on the effects of microgravity (as an obvious environmental factor in space) on morphology, proliferation, migration, and differentiation of stem cells. © 2015 International Federation for Cell Biology.
The Low-Mass Stellar Content of the Scorpius-Centaurus OB Association
NASA Technical Reports Server (NTRS)
Yorke, H.; Kunkel, M.; Brander, W.; Zinnecker, H.; Neuhauser, R.; Schmitt, J.; Mayor, M.; Udry, S.
2000-01-01
Based on ROSAT observations and data obtained with ground-based telescopes, we have carried out an extensive study of the low-mass pre-main-sequence population in Upper Scorpius, the youngest subgroup of the Scorpius-Centaurus OB association.
Variable diameter wind turbine rotor blades
Jamieson, Peter McKeich; Hornzee-Jones, Chris; Moroz, Emilian M.; Blakemore, Ralph W.
2005-12-06
A system and method for changing wind turbine rotor diameters to meet changing wind speeds and control system loads is disclosed. The rotor blades on the wind turbine are able to adjust length by extensions nested within or containing the base blade. The blades can have more than one extension in a variety of configurations. A cable winching system, a hydraulic system, a pneumatic system, inflatable or elastic extensions, and a spring-loaded jack knife deployment are some of the methods of adjustment. The extension is also protected from lightning by a grounding system.
Ground- and Space-based Observations of Horizontally-extensive Lightning Flashes
NASA Astrophysics Data System (ADS)
Zhang, D.; Cummins, K. L.; Bitzer, P. M.
2017-12-01
Horizontally-extensive lightning flashes occur frequently in association with mature and late phases of multicellular thunderstorms, both in trailing stratiform regions and horizontally-extensive anvils. The spatial relationship between these flashes and the parent cloud volume is of importance for space launch operational decision making, and is of broader scientific interest. Before this question can be accurately addressed, there is a need to understand the degree to which current lightning observation systems can depict the spatial extent of these long flashes. In this ongoing work, we will intercompare the depiction of horizontally-extensive flashes using several ground-based lightning locating systems (LLSs) located at Kennedy Space Center (KSC) with space-based observations observed by the recently-launched Geostationary Lightning Mapper (GLM) onboard the GOES-16 satellite. Ground-based datasets include the KSC Lightning Mapping Array (KSCLMA), the operational narrowband digital interferometer network MERLIN, and the combined cloud-to-ground and cloud lightning dataset produced by the U.S. National Lightning Detection Network (NLDN). The KSCLMA system is a network of VHF time-of-arrival sensors that preferentially report breakdown processes, and MERLIN is a network of VHF interferometers that point to the discharges in the horizontal plane. Observations to date indicate that MERLIN and the KSCSLMA provide similar overall descriptions of the spatial and temporal extent of these flashes, while the NLDN does not provide adequate spatial mapping of these flashes. The KSC LMA system has much better location accuracy, and provides excellent 3-dimensional representation within 100 km of KSC. It also has sufficient sensitivity to provide 2-dimensional flash mapping within 250 km of KSC. The MERLIN system provides a more-detailed representation of fast leader propagation (in 2 dimensions) with 100 km of KSC. Earlier work during the CHUVA campaign in Brazil with similar systems and the (orbital) Lightning Imaging System (LIS) has shown that the interferometric data correlated much better in space and time with the LIS optical observations. We are currently investigating this relationship at KSC, where both the LMA and interferometer perform much better than the systems used during CHUVA.
NASA Astrophysics Data System (ADS)
Akasofu, S.-I.; Kamide, Y.
1998-07-01
A new approach is needed to advance magnetospheric physics in the future to achieve a much closer integration than in the past among satellite-based researchers, ground-based researchers, and theorists/modelers. Specifically, we must find efficient ways to combine two-dimensional ground-based data and single points satellite-based data to infer three-dimensional aspects of magnetospheric disturbances. For this particular integration purpose, we propose a new project. It is designed to determine the currents on the magnetospheric equatorial plane from the ionospheric current distribution which has become available by inverting ground-based magnetic data from an extensive, systematic network of observations, combined with ground-based radar measurements of ionospheric parameters, and satellite observations of auroras, electric fields, and currents. The inversion method is based on the KRM/AMIE algorithms. In the first part of the paper, we extensively review the reliability and accuracy of the KRM and AMIE algorithms and conclude that the ionospheric quantities thus obtained are accurate enough for the next step. In the second part, the ionospheric current distribution thus obtained is projected onto the equatorial plane. This process requires a close cooperation with modelers in determining an accurate configuration of the magnetospheric field lines. If we succeed in this projection, we should be able to study the changing distribution of the currents in a vast region of the magnetospheric equatorial plane for extended periods with a time resolution of about 5 min. This process requires a model of the magnetosphere for the different phases of the magnetospheric substorm. Satellite-based observations are needed to calibrate the projection results. Agreements and disagreements thus obtained will be crucial for theoretical studies of magnetospheric plasma convection and dynamics, particularly in studying substorms. Nothing is easy in these procedures. However, unless we can overcome the associated difficulties, we may not be able to make distinct progresses. We believe that the proposed project is one way to draw the three groups closer together in advancing magnetospheric physics in the future. It is important to note that the proposed project has become possible because ground-based space physics has made a major advance during the last decade.
NASA Astrophysics Data System (ADS)
Chouika, N.; Mezrag, C.; Moutarde, H.; Rodríguez-Quintero, J.
2018-05-01
A systematic approach for the model building of Generalized Parton Distributions (GPDs), based on their overlap representation within the DGLAP kinematic region and a further covariant extension to the ERBL one, is applied to the valence-quark pion's case, using light-front wave functions inspired by the Nakanishi representation of the pion Bethe-Salpeter amplitudes (BSA). This simple but fruitful pion GPD model illustrates the general model building technique and, in addition, allows for the ambiguities related to the covariant extension, grounded on the Double Distribution (DD) representation, to be constrained by requiring a soft-pion theorem to be properly observed.
NASA Technical Reports Server (NTRS)
Myers, R. H.
1976-01-01
The depletion of ozone in the stratosphere is examined, and causes for the depletion are cited. Ground station and satellite measurements of ozone, which are taken on a worldwide basis, are discussed. Instruments used in ozone measurement are discussed, such as the Dobson spectrophotometer, which is credited with providing the longest and most extensive series of observations for ground based observation of stratospheric ozone. Other ground based instruments used to measure ozone are also discussed. The statistical differences of ground based measurements of ozone from these different instruments are compared to each other, and to satellite measurements. Mathematical methods (i.e., trend analysis or linear regression analysis) of analyzing the variability of ozone concentration with respect to time and lattitude are described. Various time series models which can be employed in accounting for ozone concentration variability are examined.
GPR application on construction foundation study
NASA Astrophysics Data System (ADS)
Amran, T. S. T.; Ismail, M. P.; Ismail, M. A.; Amin, M. S. M.; Ahmad, M. R.; Basri, N. S. M.
2017-11-01
Extensive researches and studies have been carried on radar system for commercialisation of ground penetrating radar (GPR) technology pioneered in construction, and thus claimed its rightful place in the vision of future. The application of ground penetrating radar in construction study is briefly reviewed. Based on previous experimentation and studies, this paper is focus on reinforcement bar (rebar) investigation on construction. The various data through previous references used to discuss and analyse the capability of ground penetrating radar for further improvement in construction projects especially in rebar placement in works.
Effect of hoof boots and toe-extension shoes on the forelimb kinetics of horses during walking.
Amitrano, Fernando N; Gutierrez-Nibeyro, Santiago D; Schaeffer, David J
2016-05-01
OBJECTIVE To determine and compare the effect of hoof boots (HBs) and shoes with a toe extension on stance duration, ground reaction force, and sole length in contact with the ground in nonlame horses during walking. ANIMALS 6 nonlame Standardbreds. PROCEDURES Force plate gait analyses of the forelimbs were performed while the horses were walking barefoot before manipulation of feet (baseline), while the horses were walking fitted with HBs, while the horses were walking shod with toe-extension shoes, and while the horses were walking barefoot after shoe removal. Horses underwent radiography of both forelimb feet to determine the sole length in contact with the ground when barefoot, wearing HBs, and shod with toe-extension shoes. Stance duration, ground reaction force, and sole length were compared among the various walking sessions. RESULTS Compared with baseline findings, stance duration increased significantly when horses were fitted with HBs (7%) or toe-extension shoes (5%). Peak forelimb ground reaction force was similar among walking sessions; however, time of braking force peak was significantly greater during the stance phase only when horses wore HBs. Also, the sole length in contact with the ground was significantly longer in horses fitted with HBs (14.3 cm) or shod with the toe-extension shoes (17.6 cm), compared with that for one of the barefoot hooves (12.7 cm). CONCLUSIONS AND CLINICAL RELEVANCE In nonlame horses, use of HBs prolonged the stance time and time of braking force peak, which is indicative of a slower deceleration phase during limb impact with the ground. Also, the use of HBs prolonged the deceleration phase of the stride and increased the sole length in contact with the ground.
2010-06-01
extensive case study of the relationships between the observation of in situ irregularities, UHF scintillation observed by the Scin - tillation Decision...use these space-based measurements, however, the correlation between the structures and the resulting scin - tillation must be quantified. [10] As a
NASA Astrophysics Data System (ADS)
Actis, M.; Agnetta, G.; Aharonian, F.; Akhperjanian, A.; Aleksić, J.; Aliu, E.; Allan, D.; Allekotte, I.; Antico, F.; Antonelli, L. A.; Antoranz, P.; Aravantinos, A.; Arlen, T.; Arnaldi, H.; Artmann, S.; Asano, K.; Asorey, H.; Bähr, J.; Bais, A.; Baixeras, C.; Bajtlik, S.; Balis, D.; Bamba, A.; Barbier, C.; Barceló, M.; Barnacka, A.; Barnstedt, J.; Barres de Almeida, U.; Barrio, J. A.; Basso, S.; Bastieri, D.; Bauer, C.; Becerra, J.; Becherini, Y.; Bechtol, K.; Becker, J.; Beckmann, V.; Bednarek, W.; Behera, B.; Beilicke, M.; Belluso, M.; Benallou, M.; Benbow, W.; Berdugo, J.; Berger, K.; Bernardino, T.; Bernlöhr, K.; Biland, A.; Billotta, S.; Bird, T.; Birsin, E.; Bissaldi, E.; Blake, S.; Blanch, O.; Bobkov, A. A.; Bogacz, L.; Bogdan, M.; Boisson, C.; Boix, J.; Bolmont, J.; Bonanno, G.; Bonardi, A.; Bonev, T.; Borkowski, J.; Botner, O.; Bottani, A.; Bourgeat, M.; Boutonnet, C.; Bouvier, A.; Brau-Nogué, S.; Braun, I.; Bretz, T.; Briggs, M. S.; Brun, P.; Brunetti, L.; Buckley, J. H.; Bugaev, V.; Bühler, R.; Bulik, T.; Busetto, G.; Buson, S.; Byrum, K.; Cailles, M.; Cameron, R.; Canestrari, R.; Cantu, S.; Carmona, E.; Carosi, A.; Carr, J.; Carton, P. H.; Casiraghi, M.; Castarede, H.; Catalano, O.; Cavazzani, S.; Cazaux, S.; Cerruti, B.; Cerruti, M.; Chadwick, P. M.; Chiang, J.; Chikawa, M.; Cieślar, M.; Ciesielska, M.; Cillis, A.; Clerc, C.; Colin, P.; Colomé, J.; Compin, M.; Conconi, P.; Connaughton, V.; Conrad, J.; Contreras, J. L.; Coppi, P.; Corlier, M.; Corona, P.; Corpace, O.; Corti, D.; Cortina, J.; Costantini, H.; Cotter, G.; Courty, B.; Couturier, S.; Covino, S.; Croston, J.; Cusumano, G.; Daniel, M. K.; Dazzi, F.; de Angelis, A.; de Cea Del Pozo, E.; de Gouveia Dal Pino, E. M.; de Jager, O.; de La Calle Pérez, I.; de La Vega, G.; de Lotto, B.; de Naurois, M.; de Oña Wilhelmi, E.; de Souza, V.; Decerprit, B.; Deil, C.; Delagnes, E.; Deleglise, G.; Delgado, C.; Dettlaff, T.; di Paolo, A.; di Pierro, F.; Díaz, C.; Dick, J.; Dickinson, H.; Digel, S. W.; Dimitrov, D.; Disset, G.; Djannati-Ataï, A.; Doert, M.; Domainko, W.; Dorner, D.; Doro, M.; Dournaux, J.-L.; Dravins, D.; Drury, L.; Dubois, F.; Dubois, R.; Dubus, G.; Dufour, C.; Durand, D.; Dyks, J.; Dyrda, M.; Edy, E.; Egberts, K.; Eleftheriadis, C.; Elles, S.; Emmanoulopoulos, D.; Enomoto, R.; Ernenwein, J.-P.; Errando, M.; Etchegoyen, A.; Falcone, A. D.; Farakos, K.; Farnier, C.; Federici, S.; Feinstein, F.; Ferenc, D.; Fillin-Martino, E.; Fink, D.; Finley, C.; Finley, J. P.; Firpo, R.; Florin, D.; Föhr, C.; Fokitis, E.; Font, Ll.; Fontaine, G.; Fontana, A.; Förster, A.; Fortson, L.; Fouque, N.; Fransson, C.; Fraser, G. W.; Fresnillo, L.; Fruck, C.; Fujita, Y.; Fukazawa, Y.; Funk, S.; Gäbele, W.; Gabici, S.; Gadola, A.; Galante, N.; Gallant, Y.; García, B.; García López, R. J.; Garrido, D.; Garrido, L.; Gascón, D.; Gasq, C.; Gaug, M.; Gaweda, J.; Geffroy, N.; Ghag, C.; Ghedina, A.; Ghigo, M.; Gianakaki, E.; Giarrusso, S.; Giavitto, G.; Giebels, B.; Giro, E.; Giubilato, P.; Glanzman, T.; Glicenstein, J.-F.; Gochna, M.; Golev, V.; Gómez Berisso, M.; González, A.; González, F.; Grañena, F.; Graciani, R.; Granot, J.; Gredig, R.; Green, A.; Greenshaw, T.; Grimm, O.; Grube, J.; Grudzińska, M.; Grygorczuk, J.; Guarino, V.; Guglielmi, L.; Guilloux, F.; Gunji, S.; Gyuk, G.; Hadasch, D.; Haefner, D.; Hagiwara, R.; Hahn, J.; Hallgren, A.; Hara, S.; Hardcastle, M. J.; Hassan, T.; Haubold, T.; Hauser, M.; Hayashida, M.; Heller, R.; Henri, G.; Hermann, G.; Herrero, A.; Hinton, J. A.; Hoffmann, D.; Hofmann, W.; Hofverberg, P.; Horns, D.; Hrupec, D.; Huan, H.; Huber, B.; Huet, J.-M.; Hughes, G.; Hultquist, K.; Humensky, T. B.; Huppert, J.-F.; Ibarra, A.; Illa, J. M.; Ingjald, J.; Inoue, Y.; Inoue, S.; Ioka, K.; Jablonski, C.; Jacholkowska, A.; Janiak, M.; Jean, P.; Jensen, H.; Jogler, T.; Jung, I.; Kaaret, P.; Kabuki, S.; Kakuwa, J.; Kalkuhl, C.; Kankanyan, R.; Kapala, M.; Karastergiou, A.; Karczewski, M.; Karkar, S.; Karlsson, N.; Kasperek, J.; Katagiri, H.; Katarzyński, K.; Kawanaka, N.; Kȩdziora, B.; Kendziorra, E.; Khélifi, B.; Kieda, D.; Kifune, T.; Kihm, T.; Klepser, S.; Kluźniak, W.; Knapp, J.; Knappy, A. R.; Kneiske, T.; Knödlseder, J.; Köck, F.; Kodani, K.; Kohri, K.; Kokkotas, K.; Komin, N.; Konopelko, A.; Kosack, K.; Kossakowski, R.; Kostka, P.; Kotuła, J.; Kowal, G.; Kozioł, J.; Krähenbühl, T.; Krause, J.; Krawczynski, H.; Krennrich, F.; Kretzschmann, A.; Kubo, H.; Kudryavtsev, V. A.; Kushida, J.; La Barbera, N.; La Parola, V.; La Rosa, G.; López, A.; Lamanna, G.; Laporte, P.; Lavalley, C.; Le Flour, T.; Le Padellec, A.; Lenain, J.-P.; Lessio, L.; Lieunard, B.; Lindfors, E.; Liolios, A.; Lohse, T.; Lombardi, S.; Lopatin, A.; Lorenz, E.; Lubiński, P.; Luz, O.; Lyard, E.; Maccarone, M. C.; Maccarone, T.; Maier, G.; Majumdar, P.; Maltezos, S.; Małkiewicz, P.; Mañá, C.; Manalaysay, A.; Maneva, G.; Mangano, A.; Manigot, P.; Marín, J.; Mariotti, M.; Markoff, S.; Martínez, G.; Martínez, M.; Mastichiadis, A.; Matsumoto, H.; Mattiazzo, S.; Mazin, D.; McComb, T. J. L.; McCubbin, N.; McHardy, I.; Medina, C.; Melkumyan, D.; Mendes, A.; Mertsch, P.; Meucci, M.; Michałowski, J.; Micolon, P.; Mineo, T.; Mirabal, N.; Mirabel, F.; Miranda, J. M.; Mirzoyan, R.; Mizuno, T.; Moal, B.; Moderski, R.; Molinari, E.; Monteiro, I.; Moralejo, A.; Morello, C.; Mori, K.; Motta, G.; Mottez, F.; Moulin, E.; Mukherjee, R.; Munar, P.; Muraishi, H.; Murase, K.; Murphy, A. Stj.; Nagataki, S.; Naito, T.; Nakamori, T.; Nakayama, K.; Naumann, C.; Naumann, D.; Nayman, P.; Nedbal, D.; Niedźwiecki, A.; Niemiec, J.; Nikolaidis, A.; Nishijima, K.; Nolan, S. J.; Nowak, N.; O'Brien, P. T.; Ochoa, I.; Ohira, Y.; Ohishi, M.; Ohka, H.; Okumura, A.; Olivetto, C.; Ong, R. A.; Orito, R.; Orr, M.; Osborne, J. P.; Ostrowski, M.; Otero, L.; Otte, A. N.; Ovcharov, E.; Oya, I.; Oziȩbło, A.; Paiano, S.; Pallota, J.; Panazol, J. L.; Paneque, D.; Panter, M.; Paoletti, R.; Papyan, G.; Paredes, J. M.; Pareschi, G.; Parsons, R. D.; Paz Arribas, M.; Pedaletti, G.; Pepato, A.; Persic, M.; Petrucci, P. O.; Peyaud, B.; Piechocki, W.; Pita, S.; Pivato, G.; Płatos, Ł.; Platzer, R.; Pogosyan, L.; Pohl, M.; Pojmański, G.; Ponz, J. D.; Potter, W.; Prandini, E.; Preece, R.; Prokoph, H.; Pühlhofer, G.; Punch, M.; Quel, E.; Quirrenbach, A.; Rajda, P.; Rando, R.; Rataj, M.; Raue, M.; Reimann, C.; Reimann, O.; Reimer, A.; Reimer, O.; Renaud, M.; Renner, S.; Reymond, J.-M.; Rhode, W.; Ribó, M.; Ribordy, M.; Rico, J.; Rieger, F.; Ringegni, P.; Ripken, J.; Ristori, P.; Rivoire, S.; Rob, L.; Rodriguez, S.; Roeser, U.; Romano, P.; Romero, G. E.; Rosier-Lees, S.; Rovero, A. C.; Roy, F.; Royer, S.; Rudak, B.; Rulten, C. B.; Ruppel, J.; Russo, F.; Ryde, F.; Sacco, B.; Saggion, A.; Sahakian, V.; Saito, K.; Saito, T.; Sakaki, N.; Salazar, E.; Salini, A.; Sánchez, F.; Sánchez Conde, M. Á.; Santangelo, A.; Santos, E. M.; Sanuy, A.; Sapozhnikov, L.; Sarkar, S.; Scalzotto, V.; Scapin, V.; Scarcioffolo, M.; Schanz, T.; Schlenstedt, S.; Schlickeiser, R.; Schmidt, T.; Schmoll, J.; Schroedter, M.; Schultz, C.; Schultze, J.; Schulz, A.; Schwanke, U.; Schwarzburg, S.; Schweizer, T.; Seiradakis, J.; Selmane, S.; Seweryn, K.; Shayduk, M.; Shellard, R. C.; Shibata, T.; Sikora, M.; Silk, J.; Sillanpää, A.; Sitarek, J.; Skole, C.; Smith, N.; Sobczyńska, D.; Sofo Haro, M.; Sol, H.; Spanier, F.; Spiga, D.; Spyrou, S.; Stamatescu, V.; Stamerra, A.; Starling, R. L. C.; Stawarz, Ł.; Steenkamp, R.; Stegmann, C.; Steiner, S.; Stergioulas, N.; Sternberger, R.; Stinzing, F.; Stodulski, M.; Straumann, U.; Suárez, A.; Suchenek, M.; Sugawara, R.; Sulanke, K. H.; Sun, S.; Supanitsky, A. D.; Sutcliffe, P.; Szanecki, M.; Szepieniec, T.; Szostek, A.; Szymkowiak, A.; Tagliaferri, G.; Tajima, H.; Takahashi, H.; Takahashi, K.; Takalo, L.; Takami, H.; Talbot, R. G.; Tam, P. H.; Tanaka, M.; Tanimori, T.; Tavani, M.; Tavernet, J.-P.; Tchernin, C.; Tejedor, L. A.; Telezhinsky, I.; Temnikov, P.; Tenzer, C.; Terada, Y.; Terrier, R.; Teshima, M.; Testa, V.; Tibaldo, L.; Tibolla, O.; Tluczykont, M.; Todero Peixoto, C. J.; Tokanai, F.; Tokarz, M.; Toma, K.; Torres, D. F.; Tosti, G.; Totani, T.; Toussenel, F.; Vallania, P.; Vallejo, G.; van der Walt, J.; van Eldik, C.; Vandenbroucke, J.; Vankov, H.; Vasileiadis, G.; Vassiliev, V. V.; Vegas, I.; Venter, L.; Vercellone, S.; Veyssiere, C.; Vialle, J. P.; Videla, M.; Vincent, P.; Vink, J.; Vlahakis, N.; Vlahos, L.; Vogler, P.; Vollhardt, A.; Volpe, F.; von Gunten, H. P.; Vorobiov, S.; Wagner, S.; Wagner, R. M.; Wagner, B.; Wakely, S. P.; Walter, P.; Walter, R.; Warwick, R.; Wawer, P.; Wawrzaszek, R.; Webb, N.; Wegner, P.; Weinstein, A.; Weitzel, Q.; Welsing, R.; Wetteskind, H.; White, R.; Wierzcholska, A.; Wilkinson, M. I.; Williams, D. A.; Winde, M.; Wischnewski, R.; Wiśniewski, Ł.; Wolczko, A.; Wood, M.; Xiong, Q.; Yamamoto, T.; Yamaoka, K.; Yamazaki, R.; Yanagita, S.; Yoffo, B.; Yonetani, M.; Yoshida, A.; Yoshida, T.; Yoshikoshi, T.; Zabalza, V.; Zagdański, A.; Zajczyk, A.; Zdziarski, A.; Zech, A.; Ziȩtara, K.; Ziółkowski, P.; Zitelli, V.; Zychowski, P.
2011-12-01
Ground-based gamma-ray astronomy has had a major breakthrough with the impressive results obtained using systems of imaging atmospheric Cherenkov telescopes. Ground-based gamma-ray astronomy has a huge potential in astrophysics, particle physics and cosmology. CTA is an international initiative to build the next generation instrument, with a factor of 5-10 improvement in sensitivity in the 100 GeV-10 TeV range and the extension to energies well below 100 GeV and above 100 TeV. CTA will consist of two arrays (one in the north, one in the south) for full sky coverage and will be operated as open observatory. The design of CTA is based on currently available technology. This document reports on the status and presents the major design concepts of CTA.
Thatcher, W.; Massonnet, D.
1997-01-01
Satellite radar interferometric images of Long Valley caldera show a pattern of surface deformation that resembles that expected from analysis of an extensive suite of ground-based geodetic data. Images from 2 and 4 year intervals respectively, are consistent with uniform movement rates determined from leveling surveys. Synthetic interferograms generated from ellipsoidal-inclusion source models based on inversion of the ground-based data show generally good agreement with the observed images. Two interferograms show evidence for a magmatic source southwest of the caldera in a region not covered by ground measurements. Poorer image quality in the 4 year interferogram indicates that temporal decorrelation of surface radar reflectors is progressively degrading the fringe pattern in the Long Valley region. Copyright 1997 by the American Geophysical Union.
ERIC Educational Resources Information Center
Liu, Yongcan; Fisher, Linda; Forbes, Karen; Evans, Michael
2017-01-01
This paper aims to define the knowledge base of teaching in linguistically diverse secondary schools in England. Based on extensive interviews with the teachers across two schools, the paper identifies a range of good practices centred on flexibility and differentiation. These include diversifying teaching resources by using bilingual materials…
Ground-based SMART-COMMIT Measurements for Studying Aerosol and Cloud Properties
NASA Technical Reports Server (NTRS)
Tsay, Si-Chee
2008-01-01
From radiometric principles, it is expected that the retrieved properties of extensive aerosols and clouds from reflected/emitted measurements by satellite (and/or aircraft) should be consistent with those retrieved from transmitted/emitted radiance observed at the surface. Although space-borne remote sensing observations cover large spatial domain, they are often plagued by contamination of surface signatures. Thus, ground-based in-situ and remote-sensing measurements, where signals come directly from atmospheric constituents, the sun, and/or the Earth-atmosphere interactions, provide additional information content for comparisons that confirm quantitatively the usefulness of the integrated surface, aircraft, and satellite data sets. The development and deployment of SMARTCOMMIT (Surface-sensing Measurements for Atmospheric Radiative Transfer - Chemical, Optical & Microphysical Measurements of In-situ Troposphere) mobile facilities are aimed for the optimal utilization of collocated ground-based observations as constraints to yield higher fidelity satellite retrievals and to determine any sampling bias due to target conditions. To quantify the energetics of the surface-atmosphere system and the atmospheric processes, SMART-COMMIT instruments fall into three categories: flux radiometer, radiance sensor and in-situ probe. In this paper, we will demonstrate the capability of SMART-COMMIT in recent field campaigns (e.g., CRYSTAL-FACE, UAE 2, BASEASIA, NAMMA) that were designed and executed to study the compelling variability in temporal scale of both anthropogenic and natural aerosols (e.g., biomass-burning smoke, airborne dust) and cirrus clouds. We envision robust approaches in which well-collocated ground-based measurements and space-borne observations will greatly advance our knowledge of extensive aerosols and clouds.
78 FR 22281 - Public Land Order No. 7811; Extension of Public Land Order No. 6960; WY.
Federal Register 2010, 2011, 2012, 2013, 2014
2013-04-15
...-year period. The extension is necessary to continue protection of the natural elk feeding ground... the deaf (TDD) may call the Federal Information Relay Service (FIRS) at 1-800-877-8339 to contact the... extension to continue protection of the natural elk feeding ground, winter range, and capital investments in...
DOE Office of Scientific and Technical Information (OSTI.GOV)
Actis, M
Ground-based gamma-ray astronomy has had a major breakthrough with the impressive results obtained using systems of imaging atmospheric Cherenkov telescopes. Ground-based gamma-ray astronomy has a huge potential in astrophysics, particle physics and cosmology. CTA is an international initiative to build the next generation instrument, with a factor of 5-10 improvement in sensitivity in the 100 GeV-10 TeV range and the extension to energies well below 100 GeV and above 100 TeV. CTA will consist of two arrays (one in the north, one in the south) for full sky coverage and will be operated as open observatory. The design of CTAmore » is based on currently available technology. This document reports on the status and presents the major design concepts of CTA.« less
2017-07-28
This document announces the extension of statewide temporary moratoria on the enrollment of new Medicare Part B non-emergency ground ambulance providers and suppliers and Medicare home health agencies, subunits, and branch locations in Florida, Illinois, Michigan, Texas, Pennsylvania, and New Jersey, as applicable, to prevent and combat fraud, waste, and abuse. This extension also applies to the enrollment of new non-emergency ground ambulance suppliers and home health agencies, subunits, and branch locations in Medicaid and the Children's Health Insurance Program in those states.
GIFTS EDU Ground-based Measurement Experiment
NASA Technical Reports Server (NTRS)
Zhou, Daniel K.; Smith, W. L., Sr.; Zollinger, L. J.; Huppi, R. J.; Reisse, R. A.; Larar, A. M.; Liu, X.; Tansock, J. J., Jr.; Jensen, S. M.; Revercomb, H. E.;
2007-01-01
Geosynchronous Imaging Fourier Transform Spectrometer (GIFTS) Engineering Demonstration Unit (EDU) is an imaging infrared spectrometer designed for atmospheric soundings. The EDU groundbased measurement experiment was held in Logan, Utah during September 2006 to demonstrate its extensive capabilities for geosynchronous and other applications.
Non-destructive inspection in industrial equipment using robotic mobile manipulation
NASA Astrophysics Data System (ADS)
Maurtua, Iñaki; Susperregi, Loreto; Ansuategui, Ander; Fernández, Ane; Ibarguren, Aitor; Molina, Jorge; Tubio, Carlos; Villasante, Cristobal; Felsch, Torsten; Pérez, Carmen; Rodriguez, Jorge R.; Ghrissi, Meftah
2016-05-01
MAINBOT project has developed service robots based applications to autonomously execute inspection tasks in extensive industrial plants in equipment that is arranged horizontally (using ground robots) or vertically (climbing robots). The industrial objective has been to provide a means to help measuring several physical parameters in multiple points by autonomous robots, able to navigate and climb structures, handling non-destructive testing sensors. MAINBOT has validated the solutions in two solar thermal plants (cylindrical-parabolic collectors and central tower), that are very demanding from mobile manipulation point of view mainly due to the extension (e.g. a thermal solar plant of 50Mw, with 400 hectares, 400.000 mirrors, 180 km of absorber tubes, 140m height tower), the variability of conditions (outdoor, day-night), safety requirements, etc. Once the technology was validated in simulation, the system was deployed in real setups and different validation tests carried out. In this paper two of the achievements related with the ground mobile inspection system are presented: (1) Autonomous navigation localization and planning algorithms to manage navigation in huge extensions and (2) Non-Destructive Inspection operations: thermography based detection algorithms to provide automatic inspection abilities to the robots.
NASA Technical Reports Server (NTRS)
1979-01-01
This specification establishes the natural and induced environments to which the power extension package may be exposed during ground operations and space operations with the shuttle system. Space induced environments are applicable at the Orbiter attach point interface location. All probable environments are systematically listed according to each ground and mission phase.
NASA Astrophysics Data System (ADS)
Markauskaite, Lina; Kelly, Nick; Jacobson, Michael J.
2017-12-01
This paper gives a grounded cognition account of model-based learning of complex scientific knowledge related to socio-scientific issues, such as climate change. It draws on the results from a study of high school students learning about the carbon cycle through computational agent-based models and investigates two questions: First, how do students ground their understanding about the phenomenon when they learn and solve problems with computer models? Second, what are common sources of mistakes in students' reasoning with computer models? Results show that students ground their understanding in computer models in five ways: direct observation, straight abstraction, generalisation, conceptualisation, and extension. Students also incorporate into their reasoning their knowledge and experiences that extend beyond phenomena represented in the models, such as attitudes about unsustainable carbon emission rates, human agency, external events, and the nature of computational models. The most common difficulties of the students relate to seeing the modelled scientific phenomenon and connecting results from the observations with other experiences and understandings about the phenomenon in the outside world. An important contribution of this study is the constructed coding scheme for establishing different ways of grounding, which helps to understand some challenges that students encounter when they learn about complex phenomena with agent-based computer models.
Antarctic grounding-line migration
NASA Astrophysics Data System (ADS)
Slater, T.; Konrad, H.; Shepherd, A.; Gilbert, L.; Hogg, A.; McMillan, M.; Muir, A. S.
2017-12-01
Knowledge of grounding-line position is critical for quantifying ice discharge into the ocean, as a boundary condition for numerical models of ice flow, and as an indicator of ice sheet stability. Although geological investigations have documented extensive grounding-line retreat since the period of the Last Glacial Maximum, observations of grounding line migration during the satellite era are restricted to a handful of locations. We combine satellite altimeter observations of ice-elevation change and airborne measurements of ice geometry to track movement of the Antarctic Ice Sheet grounding line. Based on these data, we estimate that 22%, 3%, and 10% of the West Antarctic, East Antarctic, and Antarctic Peninsula ice sheet grounding lines are retreating at rates faster than the typical pace since the Last Glacial Maximum, and that the continent loses over 200 km2 of grounded-ice area per year. Although by far the fastest rates of retreat occurred in the Amundsen Sea Sector, the Pine Island Glacier grounding line has stabilized - likely as a consequence of abated ocean forcing during the survey period.
NASA Astrophysics Data System (ADS)
Grawe, M.; Makela, J. J.
2016-12-01
Airglow imaging of the 630.0-nm redline emission has emerged as a useful tool for studying the properties of tsunami-ionospheric coupling in recent years, offering spatially continuous coverage of the sky with a single instrument. Past studies have shown that airglow signatures induced by tsunamis are inherently anisotropic due to the observation geometry and effects from the geomagnetic field. Here, we present details behind the techniques used to determine the parameters of the signature (orientation, wavelength, etc) with potential extensions to real or quasi-real time and a tool for interpreting the location and strength of the signatures in the field of view. We demonstrate application of the techniques to ground-based optical measurements of several tsunami-induced signatures taking place over the past five years from an imaging system in Hawaii. Additionally, these methods are extended for use on space-based observation platforms, offering advantages over ground-based installations.
USSR Space Life Sciences Digest, volume 2, no. 3
NASA Technical Reports Server (NTRS)
Lewis, C. S.
1981-01-01
Soviet scientists are making significant contributions to the field of space medicine and biology through their active manned space program, frequent biosatellites, and extensive ground-based research. An overview of the developments and direction of the USSR Space Life Sciences Program is provided.
USSR Space Life Sciences Digest, volume 2, no. 4
NASA Technical Reports Server (NTRS)
Lewis, C. S.; Donnelly, K.
1981-01-01
Soviet scientists are making significant contributions to the field of space medicine and biology through their active manned space program, frequent biosatellites, and extensive ground-based research. An overview of the developments and direction of the USSR Space Life Sciences Program is provided.
Barker, R.A.; Pernik, Maribeth
1994-01-01
The Southeastern Coastal Plain aquifer system is a coastward-sloping, wedge-shaped sand and gravel reservoir exposed in outcrop to a humid climate and drained by an extensive surface-water network. Ground-water pumpage has increased to about 765 cubic feet per second since 1900, causing water-level declines of more than 150 feet in places, while base flow to major streams has decreased about 350 cubic feet per second. The water-level declines and adjustments in recharge and discharge are not expected to seriously restrict future ground-water development.
The exponentiated Hencky energy: anisotropic extension and case studies
NASA Astrophysics Data System (ADS)
Schröder, Jörg; von Hoegen, Markus; Neff, Patrizio
2017-10-01
In this paper we propose an anisotropic extension of the isotropic exponentiated Hencky energy, based on logarithmic strain invariants. Unlike other elastic formulations, the isotropic exponentiated Hencky elastic energy has been derived solely on differential geometric grounds, involving the geodesic distance of the deformation gradient \\varvec{F} to the group of rotations. We formally extend this approach towards anisotropy by defining additional anisotropic logarithmic strain invariants with the help of suitable structural tensors and consider our findings for selected case studies.
Yude Pan; John Hom; Jennifer Jenkins; Richard Birdsey
2004-01-01
To assess what difference it might make to include spatially defined estimates of foliar nitrogen in the regional application of a forest ecosystem model (PnET-II), we composed model predictions of wood production from extensive ground-based forest inventory analysis data across the Mid-Atlantic region. Spatial variation in foliar N concentration was assigned based on...
Wireless canopy sensing network systems for automated control of irrigation and water use efficiency
USDA-ARS?s Scientific Manuscript database
Ground-based instrumentation for plant canopy sensing (infrared thermometry and spectral reflectance sensors) has been used extensively in agriculture to monitor crop status. Typically, measurements are accomplished with handheld or vehicle mounted instrumentation during limited periods of a day, an...
Gravitropism and Autotropism in Cress Roots
NASA Technical Reports Server (NTRS)
Sack, Fred D.
1998-01-01
The overall purpose of this experiment was to study how cress roots respond to a withdrawal of a gravity stimulus i.e. when and how much the roots straighten (autotropism) after curving (gravitropism). This question was studied both in extensive ground-based research and in microgravity on BioRack.
Herranz, Raul; Anken, Ralf; Boonstra, Johannes; Braun, Markus; Christianen, Peter C M; de Geest, Maarten; Hauslage, Jens; Hilbig, Reinhard; Hill, Richard J A; Lebert, Michael; Medina, F Javier; Vagt, Nicole; Ullrich, Oliver; van Loon, Jack J W A; Hemmersbach, Ruth
2013-01-01
Research in microgravity is indispensable to disclose the impact of gravity on biological processes and organisms. However, research in the near-Earth orbit is severely constrained by the limited number of flight opportunities. Ground-based simulators of microgravity are valuable tools for preparing spaceflight experiments, but they also facilitate stand-alone studies and thus provide additional and cost-efficient platforms for gravitational research. The various microgravity simulators that are frequently used by gravitational biologists are based on different physical principles. This comparative study gives an overview of the most frequently used microgravity simulators and demonstrates their individual capacities and limitations. The range of applicability of the various ground-based microgravity simulators for biological specimens was carefully evaluated by using organisms that have been studied extensively under the conditions of real microgravity in space. In addition, current heterogeneous terminology is discussed critically, and recommendations are given for appropriate selection of adequate simulators and consistent use of nomenclature.
Air and ground resonance of helicopters with elastically tailored composite rotor blades
NASA Technical Reports Server (NTRS)
Smith, Edward C.; Chopra, Inderjit
1993-01-01
The aeromechanical stability, including air resonance in hover, air resonance in forward flight, and ground resonance, of a helicopter with elastically tailored composite rotor blades is investigated. Five soft-inplane hingeless rotor configurations, featuring elastic pitch-lag, pitch-flap and extension-torsion couplings, are analyzed. Elastic couplings introduced through tailored composite blade spars can have a powerful effect on both air and ground resonance behavior. Elastic pitch-flap couplings (positive and negative) strongly affect body, rotor and dynamic inflow modes. Air resonance stability is diminished by elastic pitch-flap couplings in hover and forwrad flight. Negative pitch-lag elastic coupling has a stabilizing effect on the regressive lag mode in hover and forward flight. The negative pitch-lag coupling has a detrimental effect on ground resonance stability. Extension-torsion elastic coupling (blade pitch decreases due to tension) decreases regressive lag mode stability in both airborne and ground contact conditions. Increasing thrust levels has a beneficial influence on ground resonance stability for rotors with pitch-flap and extension-torsion coupling and is only marginally effective in improving stability of rotors with pitch-lag coupling.
Using XML Configuration-Driven Development to Create a Customizable Ground Data System
NASA Technical Reports Server (NTRS)
Nash, Brent; DeMore, Martha
2009-01-01
The Mission data Processing and Control Subsystem (MPCS) is being developed as a multi-mission Ground Data System with the Mars Science Laboratory (MSL) as the first fully supported mission. MPCS is a fully featured, Java-based Ground Data System (GDS) for telecommand and telemetry processing based on Configuration-Driven Development (CDD). The eXtensible Markup Language (XML) is the ideal language for CDD because it is easily readable and editable by all levels of users and is also backed by a World Wide Web Consortium (W3C) standard and numerous powerful processing tools that make it uniquely flexible. The CDD approach adopted by MPCS minimizes changes to compiled code by using XML to create a series of configuration files that provide both coarse and fine grained control over all aspects of GDS operation.
NASA HERMeS Hall Thruster Electrical Configuration Characterization
NASA Technical Reports Server (NTRS)
Peterson, Peter; Kamhawi, Hani; Huang, Wensheng; Yim, John; Herman, Daniel; Williams, George; Gilland, James; Hofer, Richard
2016-01-01
NASAs Hall Effect Rocket with Magnetic Shielding (HERMeS) 12.5 kW Technology Demonstration Unit-1 (TDU-1) Hall thruster has been the subject of extensive technology maturation in preparation for development into a flight ready propulsion system. Part of the technology maturation was to test the TDU-1 thruster in several ground based electrical configurations to assess the thruster robustness and suitability to successful in-space operation. The ground based electrical configuration testing has recently been demonstrated as an important step in understanding and assessing how a Hall thruster may operate differently in space compared to ground based testing, and to determine the best configuration to conduct development and qualification testing. This presentation will cover the electrical configuration testing of the TDU-1 HERMeS Hall thruster in NASA Glenn Research Centers Vacuum Facility 5. The three electrical configurations examined are the thruster body tied to facility ground, thruster floating, and finally the thruster body electrically tied to cathode common. The TDU-1 HERMeS was configured with two different exit plane boundary conditions, dielectric and conducting, to examine the influence on the electrical configuration characterization.
NASA HERMeS Hall Thruster Electrical Configuration Characterization
NASA Technical Reports Server (NTRS)
Peterson, Peter Y.; Kamhawi, Hani; Huang, Wensheng; Yim, John; Herman, Daniel; Williams, George; Gilland, James; Hofer, Richard
2015-01-01
The NASA Hall Effect Rocket with Magnetic Shielding (HERMeS) 12.5 kW Technology Demonstration Unit-1 (TDU-1) Hall thruster has been the subject of extensive technology maturation in preparation for development into a flight ready propulsion system. Part of the technology maturation was to test the TDU-1 thruster in several ground based electrical configurations to assess the thruster robustness and suitability to successful in-space operation. The ground based electrical configuration testing has recently been demonstrated as an important step in understanding and assessing how a Hall thruster may operate differently in-space compared to ground based testing, and to determine the best configuration to conduct development and qualification testing. This paper describes the electrical configuration testing of the HERMeS TDU-1 Hall thruster in NASA Glenn Research Center's Vacuum Facility 5. The three electrical configurations examined were 1) thruster body tied to facility ground, 2) thruster floating, and 3) thruster body electrically tied to cathode common. The HERMeS TDU-1 Hall thruster was also configured with two different exit plane boundary conditions, dielectric and conducting, to examine the influence on the electrical configuration characterization.
Reanalysis of water and carbon cycle models at a critical zone observatory
USDA-ARS?s Scientific Manuscript database
The Susquehanna Shale Hills Critical Zone Observatory (SSHCZO) is a forested, hill-slope catchment located in the temperate-climate of central Pennsylvania with an extensive network of ground-based instrumentation for model testing and development. In this paper we discuss the use of multi-state fi...
Study of Laser Created Metal Vapour Plasmas.
1981-09-01
ance saturation could lead to extensive ground Zcvei burnout of certain kinds of atoms or ions and that this could lead to the creation of a ground...level FORM DD I JAN ", 1473 UNCLASSIFIED SECURITY CLASSIFICATION OF THIS PACE ’l hen Dota Fnt ’UNCLASSIFIFD SS ~eUItTY CLASSIFICATION OF THIS PAqE(W"Sef...vapours. Preliminary calculations have suggested that laser resonance saturation could lead to extensive ground level burnout of certain kinds of
Atmospheric turbulence profiling with unknown power spectral density
NASA Astrophysics Data System (ADS)
Helin, Tapio; Kindermann, Stefan; Lehtonen, Jonatan; Ramlau, Ronny
2018-04-01
Adaptive optics (AO) is a technology in modern ground-based optical telescopes to compensate for the wavefront distortions caused by atmospheric turbulence. One method that allows to retrieve information about the atmosphere from telescope data is so-called SLODAR, where the atmospheric turbulence profile is estimated based on correlation data of Shack-Hartmann wavefront measurements. This approach relies on a layered Kolmogorov turbulence model. In this article, we propose a novel extension of the SLODAR concept by including a general non-Kolmogorov turbulence layer close to the ground with an unknown power spectral density. We prove that the joint estimation problem of the turbulence profile above ground simultaneously with the unknown power spectral density at the ground is ill-posed and propose three numerical reconstruction methods. We demonstrate by numerical simulations that our methods lead to substantial improvements in the turbulence profile reconstruction compared to the standard SLODAR-type approach. Also, our methods can accurately locate local perturbations in non-Kolmogorov power spectral densities.
The total carbon column observing network.
Wunch, Debra; Toon, Geoffrey C; Blavier, Jean-François L; Washenfelder, Rebecca A; Notholt, Justus; Connor, Brian J; Griffith, David W T; Sherlock, Vanessa; Wennberg, Paul O
2011-05-28
A global network of ground-based Fourier transform spectrometers has been founded to remotely measure column abundances of CO(2), CO, CH(4), N(2)O and other molecules that absorb in the near-infrared. These measurements are directly comparable with the near-infrared total column measurements from space-based instruments. With stringent requirements on the instrumentation, acquisition procedures, data processing and calibration, the Total Carbon Column Observing Network (TCCON) achieves an accuracy and precision in total column measurements that is unprecedented for remote-sensing observations (better than 0.25% for CO(2)). This has enabled carbon-cycle science investigations using the TCCON dataset, and allows the TCCON to provide a link between satellite measurements and the extensive ground-based in situ network. © 2011 The Royal Society
On the long range propagation of sound over irregular terrain
NASA Technical Reports Server (NTRS)
Howe, M. S.
1984-01-01
The theory of sound propagation over randomly irregular, nominally plane terrain of finite impedance is discussed. The analysis is an extension of the theory of coherent scatter originally proposed by Biot for an irregular rigid surface. It combines Biot's approach, wherein the surface irregularities are modeled by a homogeneous distribution of hemispherical bosses, with more conventional analyses in which the ground is modeled as a smooth plane of finite impedance. At sufficiently low frequencies the interaction of the surface irregularities with the nearfield of a ground-based source leads to the production of surface waves, which are effective in penetrating the ground shadow zone predicted for a smooth surface of the same impedance.
Photovoltaic central station step and touch potential considerations in grounding system design
NASA Technical Reports Server (NTRS)
Engmann, G.
1983-01-01
The probability of hazardous step and touch potentials is an important consideration in central station grounding system design. Steam turbine generating station grounding system design is based on accepted industry practices and there is extensive in-service experience with these grounding systems. A photovoltaic (PV) central station is a relatively new concept and there is limited experience with PV station grounding systems. The operation and physical configuration of a PV central station is very different from a steam electric station. A PV station bears some similarity to a substation and the PV station step and touch potentials might be addressed as they are in substation design. However, the PV central station is a generating station and it is appropriate to examine the effect that the differences and similarities of the two types of generating stations have on step and touch potential considerations.
Vogiatzis, Konstantinos
2012-11-15
Attiko Metro S.A., the state company ensuring the development of the Athens Metro network, has recently initiated a new extension of 7.6 km, has planned for line 3 of Athens Metro from Haidari to Piraeus "Dimotikon Theatre" towards "University of Piraeus" (forestation), connecting the major Piraeus Port with "Eleftherios Venizelos" International Airport. The Piraeus extension consists of a Tunnel Boring Machine, 2 tracks and, tunnel sections, as well as 6 stations and a forestation (New Austrian Tunnelling Method) at the end of the alignment. In order to avoid the degradation of the urban acoustic environment from ground borne noise and vibration during metro operation, the assessment of the required track types and possible noise mitigation measures was executed, and for each section and each sensitive building, the ground borne noise and vibration levels will be numerically predicted. The calculated levels were then compared with ground borne noise and vibration level criteria. The necessary mitigation measures were defined in order to guarantee, in each location along the extension, the allowable ground borne Noise and Vibration max. levels inside nearby sensitive buildings taking into account alternative Transfer Functions for ground borne noise diffusion inside the buildings. Ground borne noise levels were proven to be higher than the criterion where special track work is present and also in the case of the sensitive receptor: "Dimotikon Theatre". In order to reduce the ground borne noise levels to allowable values in these sections, the installation of tracks and special track work on a floating slab was assessed and recommended. Copyright © 2012 Elsevier B.V. All rights reserved.
C.J. Fettig; A.S. Munson; S.R. McKelvey; DeGomez T.E.
2009-01-01
Bark beetles are commonly recognized as important tree mortality agents in western coniferous forests, but relatively few species (<25) are capable of killing apparently-healthy trees. However, during the last decade extensive levels of tree mortality were attributed to bark beetle outbreaks in...
Electrophoretic separator for purifying biologicals, part 1
NASA Technical Reports Server (NTRS)
Mccreight, L. R.
1978-01-01
A program to develop an engineering model of an electrophoretic separator for purifying biologicals is summarized. An extensive mathematical modeling study and numerous ground based tests were included. Focus was placed on developing an actual electrophoretic separator of the continuous flow type, configured and suitable for flight testing as a space processing applications rocket payload.
Ground-based very high energy gamma ray astronomy: Observational highlights
NASA Technical Reports Server (NTRS)
Turver, K. E.
1986-01-01
It is now more than 20 years since the first ground based gamma ray experiments involving atmospheric Cerenkov radiation were undertaken. The present highlights in observational ground-based very high energy (VHE) gamma ray astronomy and the optimism about an interesting future for the field follow progress in these areas: (1) the detection at increased levels of confidence of an enlarged number of sources so that at present claims were made for the detection, at the 4 to 5 sd level of significance, of 8 point sources; (2) the replication of the claimed detections with, for the first time, confirmation of the nature and detail of the emission; and (3) the extension of gamma ray astronomy to the ultra high energy (UHE) domain. The pattern, if any, to emerge from the list of sources claimed so far is that X-ray binary sources appear to be copious emitters of gamma rays over at least 4 decades of energy. These X-ray sources which behave as VHE and UHE gamma ray emitters are examined.
Configurable technology development for reusable control and monitor ground systems
NASA Technical Reports Server (NTRS)
Uhrlaub, David R.
1994-01-01
The control monitor unit (CMU) uses configurable software technology for real-time mission command and control, telemetry processing, simulation, data acquisition, data archiving, and ground operations automation. The base technology is currently planned for the following control and monitor systems: portable Space Station checkout systems; ecological life support systems; Space Station logistics carrier system; and the ground system of the Delta Clipper (SX-2) in the Single-Stage Rocket Technology program. The CMU makes extensive use of commercial technology to increase capability and reduce development and life-cycle costs. The concepts and technology are being developed by McDonnell Douglas Space and Defense Systems for the Real-Time Systems Laboratory at NASA's Kennedy Space Center under the Payload Ground Operations Contract. A second function of the Real-Time Systems Laboratory is development and utilization of advanced software development practices.
Federal Register 2010, 2011, 2012, 2013, 2014
2012-05-02
... Extension of Existing Information Collection; Ground Control for Surface Coal Mines and Surface Work Areas of Underground Coal Mines AGENCY: Mine Safety and Health Administration, Labor. ACTION: Request for... inspections and investigations in coal or other mines shall be made each year for the purposes of, among other...
Comparison of crossover and jab step start techniques for base stealing in baseball.
Miyanishi, Tomohisa; Endo, So; Nagahara, Ryu
2017-11-01
Base stealing is an important tactic for increasing the chance of scoring in baseball. This study aimed to compare the crossover step (CS) and jab step (JS) starts for base stealing start performance and to clarify the differences between CS and JS starts in terms of three-dimensional lower extremity joint kinetics. Twelve male baseball players performed CS and JS starts, during which their motion and the force they applied to the ground were simultaneously recorded using a motion-capture system and two force platforms. The results showed that the normalised average forward external power, the average forward-backward force exerted by the left leg, and the forward velocities of the whole body centre of gravity generated by both legs and the left leg were significantly higher for the JS start than for the CS start. Moreover, the positive work done by hip extension during the left leg push-off was two-times greater for the JS start than the CS start. In conclusion, this study has demonstrated that the jab step start may be the better technique for a base stealing start and that greater positive work produced by left hip extension is probably responsible for producing its larger forward ground reaction force.
Di Pasquale, Andrea; Nico, Giovanni; Pitullo, Alfredo; Prezioso, Giuseppina
2018-01-16
The aim of this paper is to describe how ground-based radar interferometry can provide displacement measurements of earth dam surfaces and of vibration frequencies of its main concrete infrastructures. In many cases, dams were built many decades ago and, at that time, were not equipped with in situ sensors embedded in the structure when they were built. Earth dams have scattering properties similar to landslides for which the Ground-Based Synthetic Aperture Radar (GBSAR) technique has been so far extensively applied to study ground displacements. In this work, SAR and Real Aperture Radar (RAR) configurations are used for the measurement of earth dam surface displacements and vibration frequencies of concrete structures, respectively. A methodology for the acquisition of SAR data and the rendering of results is described. The geometrical correction factor, needed to transform the Line-of-Sight (LoS) displacement measurements of GBSAR into an estimate of the horizontal displacement vector of the dam surface, is derived. Furthermore, a methodology for the acquisition of RAR data and the representation of displacement temporal profiles and vibration frequency spectra of dam concrete structures is presented. For this study a Ku-band ground-based radar, equipped with horn antennas having different radiation patterns, has been used. Four case studies, using different radar acquisition strategies specifically developed for the monitoring of earth dams, are examined. The results of this work show the information that a Ku-band ground-based radar can provide to structural engineers for a non-destructive seismic assessment of earth dams.
Aeromechanical stability of helicopters with composite rotor blades in forward flight
NASA Technical Reports Server (NTRS)
Smith, Edward C.; Chopra, Inderjit
1992-01-01
The aeromechanical stability, including air resonance in hover, air resonance in forward flight, and ground resonance, of a helicopter with elastically tailored composite rotor blades is investigated. Five soft-inplane hingeless rotor configurations, featuring elastic pitch-lag, pitch-flap and extension-torsion couplings, are analyzed. Elastic couplings introduced through tailored composite blade spars can have a powerful effect on both air and ground resonance behavior. Elastic pitch-flap couplings (positive and negative) strongly affect body, rotor and dynamic inflow modes. Air resonance stability is diminished by elastic pitch-flap couplings in hover and forward flight. Negative pitch-lag elastic coupling has a stabilizing effect on the regressive lag mode in hover and forward flight. The negative pitch-lag coupling has a detrimental effect on ground resonance stability. Extension-torsion elastic coupling (blade pitch decreases due to tension) decreases regressive lag mode stability in both airborne and ground contact conditions. Increasing thrust levels has a beneficial influence on ground resonance stability for rotors with pitch-flap and extension-torsion coupling and is only marginally effective in improving stability of rotors with pitch-lag coupling.
The GSFC Mark-2 three band hand-held radiometer. [thematic mapper for ground truth data collection
NASA Technical Reports Server (NTRS)
Tucker, C. J.; Jones, W. H.; Kley, W. A.; Sundstrom, G. J.
1980-01-01
A self-contained, portable, hand-radiometer designed for field usage was constructed and tested. The device, consisting of a hand-held probe containing three sensors and a strap supported electronic module, weighs 4 1/2 kilograms. It is powered by flashlight and transistor radio batteries, utilizes two silicon and one lead sulfide detectors, has three liquid crystal displays, sample and hold radiometric sampling, and its spectral configuration corresponds to LANDSAT-D's thematic mapper bands. The device was designed to support thematic mapper ground-truth data collection efforts and to facilitate 'in situ' ground-based remote sensing studies of natural materials. Prototype instruments were extensively tested under laboratory and field conditions with excellent results.
Anken, Ralf; Boonstra, Johannes; Braun, Markus; Christianen, Peter C.M.; de Geest, Maarten; Hauslage, Jens; Hilbig, Reinhard; Hill, Richard J.A.; Lebert, Michael; Medina, F. Javier; Vagt, Nicole; Ullrich, Oliver
2013-01-01
Abstract Research in microgravity is indispensable to disclose the impact of gravity on biological processes and organisms. However, research in the near-Earth orbit is severely constrained by the limited number of flight opportunities. Ground-based simulators of microgravity are valuable tools for preparing spaceflight experiments, but they also facilitate stand-alone studies and thus provide additional and cost-efficient platforms for gravitational research. The various microgravity simulators that are frequently used by gravitational biologists are based on different physical principles. This comparative study gives an overview of the most frequently used microgravity simulators and demonstrates their individual capacities and limitations. The range of applicability of the various ground-based microgravity simulators for biological specimens was carefully evaluated by using organisms that have been studied extensively under the conditions of real microgravity in space. In addition, current heterogeneous terminology is discussed critically, and recommendations are given for appropriate selection of adequate simulators and consistent use of nomenclature. Key Words: 2-D clinostat—3-D clinostat—Gravity—Magnetic levitation—Random positioning machine—Simulated microgravity—Space biology. Astrobiology 13, 1–17. PMID:23252378
NASA Technical Reports Server (NTRS)
Demoz, Belay; Whiteman, David; Gentry, Bruce; Schwemmer, Geary; Evans, Keith; DiGirolamo, Paolo; Comer, Joseph
2005-01-01
A large array of state-of-the-art ground-based and airborne remote and in-situ sensors were deployed during the International H2O Project (THOP), a field experiment that took place over the Southern Great Plains (SGP) of the United States from 13 May to 30 June 2002. These instruments provided extensive measurements of water vapor mixing ratio in order to better understand the influence of its variability on convection and on the skill of quantitative precipitation prediction (Weckwerth et all, 2004). Among the instrument deployed were ground based lidars from NASA/GSFC that included the Scanning Raman Lidar (SRL), the Goddard Laboratory for Observing Winds (GLOW), and the Holographic Airborne Rotating Lidar Instrument Experiment (HARLIE). A brief description of the three lidars is given below. This study presents ground-based measurements of wind, boundary layer structure and water vapor mixing ratio measurements observed by three co-located lidars during MOP at the MOP ground profiling site in the Oklahoma Panhandle (hereafter referred as Homestead). This presentation will focus on the evolution and variability of moisture and wind in the boundary layer when frontal and/or convergence boundaries (e.g. bores, dry lines, thunderstorm outflows etc) were observed.
Inverse modeling of Texas NOx emissions using space-based and ground-based NO2 observations
NASA Astrophysics Data System (ADS)
Tang, W.; Cohan, D. S.; Lamsal, L. N.; Xiao, X.; Zhou, W.
2013-11-01
Inverse modeling of nitrogen oxide (NOx) emissions using satellite-based NO2 observations has become more prevalent in recent years, but has rarely been applied to regulatory modeling at regional scales. In this study, OMI satellite observations of NO2 column densities are used to conduct inverse modeling of NOx emission inventories for two Texas State Implementation Plan (SIP) modeling episodes. Addition of lightning, aircraft, and soil NOx emissions to the regulatory inventory narrowed but did not close the gap between modeled and satellite-observed NO2 over rural regions. Satellite-based top-down emission inventories are created with the regional Comprehensive Air Quality Model with extensions (CAMx) using two techniques: the direct scaling method and discrete Kalman filter (DKF) with decoupled direct method (DDM) sensitivity analysis. The simulations with satellite-inverted inventories are compared to the modeling results using the a priori inventory as well as an inventory created by a ground-level NO2-based DKF inversion. The DKF inversions yield conflicting results: the satellite-based inversion scales up the a priori NOx emissions in most regions by factors of 1.02 to 1.84, leading to 3-55% increase in modeled NO2 column densities and 1-7 ppb increase in ground 8 h ozone concentrations, while the ground-based inversion indicates the a priori NOx emissions should be scaled by factors of 0.34 to 0.57 in each region. However, none of the inversions improve the model performance in simulating aircraft-observed NO2 or ground-level ozone (O3) concentrations.
Inverse modeling of Texas NOx emissions using space-based and ground-based NO2 observations
NASA Astrophysics Data System (ADS)
Tang, W.; Cohan, D.; Lamsal, L. N.; Xiao, X.; Zhou, W.
2013-07-01
Inverse modeling of nitrogen oxide (NOx) emissions using satellite-based NO2 observations has become more prevalent in recent years, but has rarely been applied to regulatory modeling at regional scales. In this study, OMI satellite observations of NO2 column densities are used to conduct inverse modeling of NOx emission inventories for two Texas State Implementation Plan (SIP) modeling episodes. Addition of lightning, aircraft, and soil NOx emissions to the regulatory inventory narrowed but did not close the gap between modeled and satellite observed NO2 over rural regions. Satellite-based top-down emission inventories are created with the regional Comprehensive Air Quality Model with extensions (CAMx) using two techniques: the direct scaling method and discrete Kalman filter (DKF) with Decoupled Direct Method (DDM) sensitivity analysis. The simulations with satellite-inverted inventories are compared to the modeling results using the a priori inventory as well as an inventory created by a ground-level NO2 based DKF inversion. The DKF inversions yield conflicting results: the satellite-based inversion scales up the a priori NOx emissions in most regions by factors of 1.02 to 1.84, leading to 3-55% increase in modeled NO2 column densities and 1-7 ppb increase in ground 8 h ozone concentrations, while the ground-based inversion indicates the a priori NOx emissions should be scaled by factors of 0.34 to 0.57 in each region. However, none of the inversions improve the model performance in simulating aircraft-observed NO2 or ground-level ozone (O3) concentrations.
A Self-Tuning Kalman Filter for Autonomous Navigation Using the Global Positioning System (GPS)
NASA Technical Reports Server (NTRS)
Truong, Son H.
1999-01-01
Most navigation systems currently operated by NASA are ground-based, and require extensive support to produce accurate results. Recently developed systems that use Kalman filter and GPS (Global Positioning Systems) data for orbit determination greatly reduce dependency on ground support, and have potential to provide significant economies for NASA spacecraft navigation. These systems, however, still rely on manual tuning from analysts. A sophisticated neuro-fuzzy component fully integrated with the flight navigation system can perform the self-tuning capability for the Kalman filter and help the navigation system recover from estimation errors in real time.
A Self-Tuning Kalman Filter for Autonomous Navigation using the Global Positioning System (GPS)
NASA Technical Reports Server (NTRS)
Truong, S. H.
1999-01-01
Most navigation systems currently operated by NASA are ground-based, and require extensive support to produce accurate results. Recently developed systems that use Kalman filter and GPS data for orbit determination greatly reduce dependency on ground support, and have potential to provide significant economies for NASA spacecraft navigation. These systems, however, still rely on manual tuning from analysts. A sophisticated neuro-fuzzy component fully integrated with the flight navigation system can perform the self-tuning capability for the Kalman filter and help the navigation system recover from estimation errors in real time.
E-4 Test Facility Design Status
NASA Technical Reports Server (NTRS)
Ryan, Harry; Canady, Randy; Sewell, Dale; Rahman, Shamim; Gilbrech, Rick
2001-01-01
Combined-cycle propulsion technology is a strong candidate for meeting NASA space transportation goals. Extensive ground testing of integrated air-breathing/rocket system (e.g., components, subsystems and engine systems) across all propulsion operational modes (e.g., ramjet, scramjet) will be needed to demonstrate this propulsion technology. Ground testing will occur at various test centers based on each center's expertise. Testing at the NASA John C. Stennis Space Center will be primarily concentrated on combined-cycle power pack and engine systems at sea level conditions at a dedicated test facility, E-4. This paper highlights the status of the SSC E-4 test Facility design.
Plant phenology in western Canada: trends and links to the view from space.
Beaubien, Elisabeth G; Hall-Beyer, Mryka
2003-01-01
One feature of climate change is the trends to earlier spring onset in many north temperate areas of the world. The timing of spring flowering and leafing of perennial plants is largely controlled by temperature accumulation; both temperature and phenological records illustrate changes in recent decades. Phenology studies date back over a century, with extensive databases existing for western Canada. Earlier spring flowering has been noted for many woody plants, with larger trends seen for species that develop at spring's start. Implications for ecosystems of trends to earlier spring arrival include changes in plant species composition, changes in timing and distribution of pests and disease, and potentially disrupted ecological interactions. While Alberta has extensive phenology databases (for species, years, and geographic coverage) for recent decades, these data cannot provide continuous ground coverage. There is great potential for phenological data to provide ground validation for satellite imagery interpretation, especially as new remote sensors are becoming available. Phenological networks are experiencing a resurgence of interest in Canada (www.plantwatch.ca) and globally, and linking these ground-based observations with the view from space will greatly enhance our capacity to track the biotic response to climate changes.
Modular space station phase B extension integrated ground operations
NASA Technical Reports Server (NTRS)
Selegue, D. F.
1971-01-01
Requirements for development test, manufacturing, facilities, GSE, training, logistics support, and launch operations are described. The prime integrating requirement is the early establishment of a common data base and its use throughout the design, development, and operational life of the station. The common data base is defined, and the concept of its use is presented. Development requirements for the station modules and subsystems are outlined along with a master development phasing chart.
2018-01-30
This document announces the extension of statewide temporary moratoria on the enrollment of new Medicare Part B non-emergency ground ambulance providers and suppliers and Medicare home health agencies, subunits, and branch locations in Florida, Illinois, Michigan, Texas, Pennsylvania, and New Jersey, as applicable, to prevent and combat fraud, waste, and abuse. This extension also applies to the enrollment of new non-emergency ground ambulance suppliers and home health agencies, subunits, and branch locations in Medicaid and the Children's Health Insurance Program in those states. For purposes of these moratoria, providers that were participating as network providers in one or more Medicaid managed care organizations prior to January 1, 2018 will not be considered "newly enrolling" when they are required to enroll with the State Medicaid agency pursuant to a new statutory requirement, and thus will not be subject to the moratoria.
Inverse Modeling of Texas NOx Emissions Using Space-Based and Ground-Based NO2 Observations
NASA Technical Reports Server (NTRS)
Tang, Wei; Cohan, D.; Lamsal, L. N.; Xiao, X.; Zhou, W.
2013-01-01
Inverse modeling of nitrogen oxide (NOx) emissions using satellite-based NO2 observations has become more prevalent in recent years, but has rarely been applied to regulatory modeling at regional scales. In this study, OMI satellite observations of NO2 column densities are used to conduct inverse modeling of NOx emission inventories for two Texas State Implementation Plan (SIP) modeling episodes. Addition of lightning, aircraft, and soil NOx emissions to the regulatory inventory narrowed but did not close the gap between modeled and satellite observed NO2 over rural regions. Satellitebased top-down emission inventories are created with the regional Comprehensive Air Quality Model with extensions (CAMx) using two techniques: the direct scaling method and discrete Kalman filter (DKF) with Decoupled Direct Method (DDM) sensitivity analysis. The simulations with satellite-inverted inventories are compared to the modeling results using the a priori inventory as well as an inventory created by a ground-level NO2 based DKF inversion. The DKF inversions yield conflicting results: the satellite based inversion scales up the a priori NOx emissions in most regions by factors of 1.02 to 1.84, leading to 3-55% increase in modeled NO2 column densities and 1-7 ppb increase in ground 8 h ozone concentrations, while the ground-based inversion indicates the a priori NOx emissions should be scaled by factors of 0.34 to 0.57 in each region. However, none of the inversions improve the model performance in simulating aircraft-observed NO2 or ground-level ozone (O3) concentrations.
The peregrine falcon in Arizona: Habitat utilization and management recommendations
Ellis, D.H.
1982-01-01
The peregrine falcon once bred in significant numbers in Arizona. Good documentation is available for specific breeding sites and an additional 20 general locations. This report, based on the published literature, an extensive personal contact survey, an aerial habitat inventory (over 124 hours air time), and ground visits to over 300 locations, provides information on habitat preferences and management practices which can contribute to the bird's survival. In seeking to identify the habitat preferences of the falcon, many site description factors were examined. Those traits which appeared common to most recent Arizona sites (and therefore most useful in evaluating habitat) were: elevation less than 9,000 feet, cliffs tall or very tall, cliffs extensive, topographic relief high, and surface water readily available. All recent sites are in extensive canyon systems or in extensive mountain ranges. Using a habitat evaluation key derived from the traits common to known breeding sites, all cliff regions in Arizona and the Navajo Indian Reservation were flown and evaluated for suitability. Nineteen falcon eyries located in subsequent ground visits were all in areas previously ranked acceptable or better. Many management alternatives are discussed: management of information on breeding sites, habitat preservation, controlling disruptive human activities, and enhancing productivity through the creation of suitable breeding ledges, providing pesticide free prey, or direct reintroductions. Given their privacy (and an increasingly pesticide free environment) the peregrine falcon will likely exist indefinitely in suitable areas across Arizona.
NASA Astrophysics Data System (ADS)
Sixiang, Chen; Daopin, Chen; Ming, Zhang; Xiao, Huang; Jian, He; Zhijie, He
2017-05-01
Aimed at the actual situation of fish death in fish ponds near the power transmission line towers after the thunderstorm happened in Guangdong Province in China, this paper studied the influence of the ground current on fish in the pond. Firstly, This paper studied the current density of the fish without protection. On this basis, paper studied the horizontal pole with full-shielded, the vertical pole with half-shielded, the horizontal pole with extension three kinds of protective measures and effects. Finally an effective protection scheme was put forward according to the engineering practice. The results can provide some engineering guidance and quantitative basis for the design and modification of grounding devices when the tower is adjacent to the fish ponds in southern China.
NASA/RAE collaboration on nonlinear control using the F-8C digital fly-by-wire aircraft
NASA Technical Reports Server (NTRS)
Butler, G. F.; Corbin, M. J.; Mepham, S.; Stewart, J. F.; Larson, R. R.
1983-01-01
Design procedures are reviewed for variable integral control to optimize response (VICTOR) algorithms and results of preliminary flight tests are presented. The F-8C aircraft is operated in the remotely augmented vehicle (RAV) mode, with the control laws implemented as FORTRAN programs on a ground-based computer. Pilot commands and sensor information are telemetered to the ground, where the data are processed to form surface commands which are then telemetered back to the aircraft. The RAV mode represents a singlestring (simplex) system and is therefore vulnerable to a hardover since comparison monitoring is not possible. Hence, extensive error checking is conducted on both the ground and airborne computers to prevent the development of potentially hazardous situations. Experience with the RAV monitoring and validation procedures is described.
Ground-Water Occurrence and Contribution to Streamflow, Northeast Maui, Hawaii
Gingerich, Stephen B.
1999-01-01
The study area lies on the northern flank of the East Maui Volcano (Haleakala) and covers about 129 square miles between the drainage basins of Maliko Gulch to the west and Makapipi Stream to the east. About 989 million gallons per day of rainfall and 176 million gallons per day of fog drip reaches the study area and about 529 million gallons per day enters the ground-water system as recharge. Average annual ground-water withdrawal from wells totals only about 3 million gallons per day; proposed (as of 1998) additional withdrawals total about 18 million gallons per day. Additionally, tunnels and ditches of an extensive irrigation network directly intercept at least 10 million gallons per day of ground water. The total amount of average annual streamflow in gaged stream subbasins upstream of 1,300 feet altitude is about 255 million gallons per day and the total amount of average annual base flow is about 62 million gallons per day. Six major surface-water diversion systems in the study area have diverted an average of 163 million gallons per day of streamflow (including nearly all base flow of diverted streams) for irrigation and domestic supply in central Maui during 1925-97. Fresh ground water is found in two main forms. West of Keanae Valley, ground-water flow appears to be dominated by a variably saturated system. A saturated zone in the uppermost rock unit, the Kula Volcanics, is separated from a freshwater lens near sea level by an unsaturated zone in the underlying Honomanu Basalt. East of Keanae Valley, the ground-water system appears to be fully saturated above sea level to altitudes greater than 2,000 feet. The total average annual streamflow of gaged streams west of Keanae Valley is about 140 million gallons per day at 1,200 feet to 1,300 feet altitude. It is not possible to estimate the total average annual streamflow at the coast. All of the base flow measured in the study area west of Keanae Valley represents ground-water discharge from the high-elevation saturated zone. Total average daily ground-water discharge from the high-elevation saturated zone upstream of 1,200 feet altitude is greater than 38 million gallons per day, all of which is eventually removed from the streams by surface-water diversion systems. Perennial streamflow has been measured at altitudes greater than 3,000 feet in several of the streams. Discharge from the high-elevation saturated zone is persistent even during periods of little rainfall. The total average annual streamflow of the gaged streams east of Keanae Valley is about 109 million gallons per day at about 1,300 feet altitude. It is not possible to estimate the total average annual streamflow at the coast nor at higher altitudes. All of the base flow measured east of Keanae Valley represents ground-water discharge from the vertically extensive freshwater-lens system. Total average daily ground-water discharge to gaged streams upstream of 1,200 feet altitude is about 27 million gallons per day. About 19 million gallons per day of ground water discharges through the Kula and Hana Volcanics between about 500 feet and 1,300 feet altitude in the gaged stream sub-basins. About 13 million gallons per day of this discharge is in Hanawi Stream. The total ground-water discharge above 500 feet altitude in this part of the study area is greater than 56 million gallons per day.
Dairy farming on permanent grassland: can it keep up?
Kellermann, M; Salhofer, K
2014-10-01
Based on an extensive data set for southern Germany, we compared the productive performance of dairy farms that operate solely on permanent grassland and dairy farms using fodder crops from arable land. We allowed for heterogeneous production technologies and identified more intensive and extensive production systems for both types of farms, whereby we based our notion of intensive versus extensive dairy production on differences in stocking density and milk yield per cow and year. To be able to compare the productivity levels and productivity developments of the various groups of farms, we developed a group- and chain-linked multilateral productivity index. We also analyzed how technical change, technical efficiency change, and a scale change effect contribute to productivity growth between the years 2000 and 2008. Our results revealed that permanent grassland farms can generally keep up with fodder-crop farms, even in an intensive production setting. However, extensively operating farms, especially those on permanent grassland, significantly lag behind in productivity and productivity change and run the risk of losing ground. Copyright © 2014 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.
Interdisciplinary Common Ground: Techniques and Attentional Processes
ERIC Educational Resources Information Center
Arvidson, P. Sven
2014-01-01
Common ground in the interdisciplinary research process is the pivot from disciplinary to interdisciplinary perspective. As thinking moves from disciplinary to interdisciplinary, what is the shape or structure of attention, how does intellectual content transform in the attending process? Four common ground techniques--extension, redefinition,…
Containerless preparation of advanced optical glasses: Experiment 77F095
NASA Technical Reports Server (NTRS)
Happe, R. A.; Kim, K. S.
1982-01-01
Containerless processing of optical glasses was studied in preparation for space shuttle MEA flight experiments. Ground based investigation, experiment/hardware coordination activities and development of flight experiment and sample characterization plans were investigated. In the ground based investigation over 100 candidate glass materials for space processing were screened and promising compositions were identified. The system of Nb2O5-TiO2-CaO was found to be very rich with containerless glass compositions and as extensive number of the oxides combinations were tried resulting in a glass formation ternary phase diagram. The frequent occurrence of glass formation by containerless processing among the compositions for which no glass formations were previously reported indicated the possibility and an advantage of containerless processing in a terrestrial environment.
An expert system shell for inferring vegetation characteristics
NASA Technical Reports Server (NTRS)
Harrison, P. Ann; Harrison, Patrick R.
1992-01-01
The NASA VEGetation Workbench (VEG) is a knowledge based system that infers vegetation characteristics from reflectance data. The report describes the extensions that have been made to the first generation version of VEG. An interface to a file of unkown cover type data has been constructed. An interface that allows the results of VEG to be written to a file has been implemented. A learning system that learns class descriptions from a data base of historical cover type data and then uses the learned class descriptions to classify an unknown sample has been built. This system has an interface that integrates it into the rest of VEG. The VEG subgoal PROPORTION.GROUND.COVER has been completed and a number of additional techniques that infer the proportion ground cover of a sample have been implemented.
Search for tachyons associated with extensive air showers in the ground level cosmic radiation
NASA Technical Reports Server (NTRS)
Masjed, H. F.; Ashton, F.
1985-01-01
Events detected in a shielded plastic scintillation counter occurring in the 26 microsec preceding the arrival of an extensive air shower at ground level with local electron density or = 20 m to the -2 power and the 240 microsec after its arrival have been studied. No significant excess of events (tachyons) arriving in the early time domain have been observed in a sample of 11,585 air shower triggers.
Novel quantum phase transition from bounded to extensive entanglement
Zhang, Zhao; Ahmadain, Amr
2017-01-01
The nature of entanglement in many-body systems is a focus of intense research with the observation that entanglement holds interesting information about quantum correlations in large systems and their relation to phase transitions. In particular, it is well known that although generic, many-body states have large, extensive entropy, ground states of reasonable local Hamiltonians carry much smaller entropy, often associated with the boundary length through the so-called area law. Here we introduce a continuous family of frustration-free Hamiltonians with exactly solvable ground states and uncover a remarkable quantum phase transition whereby the entanglement scaling changes from area law into extensively large entropy. This transition shows that entanglement in many-body systems may be enhanced under special circumstances with a potential for generating “useful” entanglement for the purpose of quantum computing and that the full implications of locality and its restrictions on possible ground states may hold further surprises. PMID:28461464
Novel quantum phase transition from bounded to extensive entanglement.
Zhang, Zhao; Ahmadain, Amr; Klich, Israel
2017-05-16
The nature of entanglement in many-body systems is a focus of intense research with the observation that entanglement holds interesting information about quantum correlations in large systems and their relation to phase transitions. In particular, it is well known that although generic, many-body states have large, extensive entropy, ground states of reasonable local Hamiltonians carry much smaller entropy, often associated with the boundary length through the so-called area law. Here we introduce a continuous family of frustration-free Hamiltonians with exactly solvable ground states and uncover a remarkable quantum phase transition whereby the entanglement scaling changes from area law into extensively large entropy. This transition shows that entanglement in many-body systems may be enhanced under special circumstances with a potential for generating "useful" entanglement for the purpose of quantum computing and that the full implications of locality and its restrictions on possible ground states may hold further surprises.
Orbital Verification of the CXO High-Resolution Mirror Assembly Alignment and Vignetting
NASA Technical Reports Server (NTRS)
Gaetz, T. J.; Jerius, D.; Edgar, R. J.; VanSpeybroeck, L. P.; Schwartz, D. A.; Markevitch, M.; Schulz, N. S.
2000-01-01
Prior to launch, the High Resolution Mirror Assembly (HRMA) of the Chandra X-ray Observatory underwent extensive ground testing at the X-ray Calibration Facility (XRCF) at the Marshall Space Flight Center in Huntsville. Observations made during the post-launch Orbital Activation and Calibration period, allow the on-orbit condition of the X-ray optics to be assessed. Based on these ground-based and on-orbit data, we examine the alignment of the x-ray optics based on the PSF, and the boresight and alignment of the optical axis alignment relative to the detectors. We examine the vignetting and the single reflection ghost suppression properties of the telescope. Slight imperfections in alignment lead to a small azimuthal dependence of the off-axis area; the morphology of off-axis images also shows an additional small azimuthal dependence varying as 1/2 the off-axis azimuth angle.
Integrated layout based Monte-Carlo simulation for design arc optimization
NASA Astrophysics Data System (ADS)
Shao, Dongbing; Clevenger, Larry; Zhuang, Lei; Liebmann, Lars; Wong, Robert; Culp, James
2016-03-01
Design rules are created considering a wafer fail mechanism with the relevant design levels under various design cases, and the values are set to cover the worst scenario. Because of the simplification and generalization, design rule hinders, rather than helps, dense device scaling. As an example, SRAM designs always need extensive ground rule waivers. Furthermore, dense design also often involves "design arc", a collection of design rules, the sum of which equals critical pitch defined by technology. In design arc, a single rule change can lead to chain reaction of other rule violations. In this talk we present a methodology using Layout Based Monte-Carlo Simulation (LBMCS) with integrated multiple ground rule checks. We apply this methodology on SRAM word line contact, and the result is a layout that has balanced wafer fail risks based on Process Assumptions (PAs). This work was performed at the IBM Microelectronics Div, Semiconductor Research and Development Center, Hopewell Junction, NY 12533
1993 Earth Observing System reference handbook
NASA Technical Reports Server (NTRS)
Asrar, Ghassem (Editor); Dokken, David Jon (Editor)
1993-01-01
Mission to Planet Earth (MTPE) is a NASA-sponsored concept that uses space- and ground-based measurement systems to provide the scientific basis for understanding global change. The space-based components of MTPE will provide a constellation of satellites to monitor the Earth from space. Sustained observations will allow researchers to monitor climate variables overtime to determine trends; however, space-based monitoring alone is not sufficient. A comprehensive data and information system, a community of scientists performing research with the data acquired, and extensive ground campaigns are all important components. Brief descriptions of the various elements that comprise the overall mission are provided. The Earth Observing System (EOS) - a series of polar-orbiting and low-inclination satellites for long-term global observations of the land surface, biosphere, solid Earth, atmosphere, and oceans - is the centerpiece of MTPE. The elements comprising the EOS mission are described in detail.
Koo, Ok-Kyung; Baker, Christopher A; Kim, Hyun-Jung; Park, Si Hong; Ricke, Steven C
2016-09-01
The purpose of this study was to characterize the microbial community in ground pork using molecular approaches. Forty six ground pork products were purchased from local stores in the north central area of South Korea. Aerobic plate counts varied 4.23 ± 5.14 × 10(5) CFU/g with the range between 5.00 × 10(3) and 1.85 × 10(6) CFU/g for ground pork samples. Four ground meat samples were further processed for metagenomic analysis. Pseudomonas species was the most relative abundant with a wide range occurring (1.72 to 77.7%) as part of the microbial genera in ground pork. Bacteria such as Carnobacterium, Yersinia, Photobacterium were also identified in ground pork. Despite the prominence of certain genera across all samples there was still extensive microbial diversity among ground pork products that originated from different slaughter houses and were processed in different markets. Such diversity indicates that designing interventions to extend shelf life may be hampered by the extensive variability in the microbial consortia associated with pork products. However, this diversity may be useful for developing microbial traceability signatures unique to a slaughter house or a particular market.
NASA Technical Reports Server (NTRS)
Su, Ching-Hua
2015-01-01
A low gravity material experiment will be performed in the Material Science Research Rack (MSRR) on International Space Station (ISS). The flight experiment will conduct crystal growths of ZnSe and related ternary compounds, such as ZnSeS and ZnSeTe, by physical vapor transport (PVT). The main objective of the project is to determine the relative contributions of gravity-driven fluid flows to the compositional distribution, incorporation of impurities and defects, and deviation from stoichiometry observed in the grown crystals as results of buoyancy-driven convection and growth interface fluctuations caused by irregular fluid-flows on Earth. The investigation consists of extensive ground-based experimental and theoretical research efforts and concurrent flight experimentation. The objectives of the ground-based studies are (1) obtain the experimental data and conduct the analyses required to define the optimum growth parameters for the flight experiments, (2) perfect various characterization techniques to establish the standard procedure for material characterization, (3) quantitatively establish the characteristics of the crystals grown on Earth as a basis for subsequent comparative evaluations of the crystals grown in a low-gravity environment and (4) develop theoretical and analytical methods required for such evaluations. ZnSe and related ternary compounds have been grown by vapor transport technique with real time in-situ non-invasive monitoring techniques. The grown crystals have been characterized extensively by various techniques to correlate the grown crystal properties with the growth conditions. This talk will focus on the ground-based studies on the PVT crystal growth of ZnSe and related ternary compounds, especially the effects of different growth orientations related to gravity direction on the grown crystals.
Crystal Growth of Ternary Compound Semiconductors in Low Gravity Environment
NASA Technical Reports Server (NTRS)
Su, Ching-Hua
2014-01-01
A low gravity material experiment will be performed in the Material Science Research Rack (MSRR) on International Space Station (ISS). There are two sections of the flight experiment: (I) crystal growth of ZnSe and related ternary compounds, such as ZnSeS and ZnSeTe, by physical vapor transport (PVT) and (II) melt growth of CdZnTe by directional solidification. The main objective of the project is to determine the relative contributions of gravity-driven fluid flows to the compositional distribution, incorporation of impurities and defects, and deviation from stoichiometry observed in the grown crystals as results of buoyancy-driven convection and growth interface fluctuations caused by irregular fluid-flows on Earth. The investigation consists of extensive ground-based experimental and theoretical research efforts and concurrent flight experimentation. This talk will focus on the ground-based studies on the PVT crystal growth of ZnSe and related ternary compounds. The objectives of the ground-based studies are (1) obtain the experimental data and conduct the analyses required to define the optimum growth parameters for the flight experiments, (2) perfect various characterization techniques to establish the standard procedure for material characterization, (3) quantitatively establish the characteristics of the crystals grown on Earth as a basis for subsequent comparative evaluations of the crystals grown in a low-gravity environment and (4) develop theoretical and analytical methods required for such evaluations. ZnSe and related ternary compounds have been grown by vapor transport technique with real time in-situ non-invasive monitoring techniques. The grown crystals have been characterized extensively by various techniques to correlate the grown crystal properties with the growth conditions.
GK Dra: a delta Scuti Star in a New Eclipsing System Discovered by Hipparcos
NASA Astrophysics Data System (ADS)
Dallaporta, Sergio; Tomov, Toma; Zwitter, Tomaz; Munari, Ulisse
2002-09-01
GK Dra has been discovered by the Hipparcos mission as a 17 days eclipsing binary. We present here the first ground-based study of this star, based on extensive BV photoelectric photometry. We found a period of 9.974 days, equal depth primary and secondary eclipse (m=0.35 mag), no color variation in eclipse, and one of the components being a Sct star with an amplitude of 0.04 mag and a period of about 2.7 hours.
Cox, S.E.
2003-01-01
Estimates of residence time of ground water beneath Submarine Base Bangor and vicinity ranged from less than 50 to 4,550 years before present, based on analysis of the environmental tracers tritium, chlorofluorocarbons (CFCs), and carbon-14 (14C), in 33 ground-water samples collected from wells tapping the ground-water system. The concentrations of multiple environmental tracers tritium, CFCs, and 14C were used to classify ground water as modern (recharged after 1953), pre-modern (recharged prior to 1953), or indeterminate. Estimates of the residence time of pre-modern ground water were based on evaluation of 14C of dissolved inorganic carbon present in ground water using geochemical mass-transfer modeling to account for the interactions of the carbon in ground water with carbon of the aquifer sediments. Ground-water samples were obtained from two extensive aquifers and from permeable interbeds within the thick confining unit separating the sampled aquifers. Estimates of ground-water residence time for all ground-water samples from the shallow aquifer were less than 45 years and were classified as modern. Estimates of the residence time of ground water in the permeable interbeds within the confining unit ranged from modern to 4,200 years and varied spatially. Near the recharge area, residence times in the permeable interbeds typically were less than 800 years, whereas near the discharge area residence times were in excess of several thousand years. In the deeper aquifers, estimates of ground-water residence times typically were several thousand years but ranged from modern to 4,550 years. These estimates of ground-water residence time based on 14C were often larger than estimates of ground-water residence time developed by particle-tracking analysis using a ground-water flow model. There were large uncertainties?on the order of 1,000-2,000 years?in the estimates based on 14C. Modern ground-water tracers found in some samples from large-capacity production wells screened in the deeper aquifer may be the result of preferential ground-water pathways or induced downward flow caused by pumping stress. Spatial variations in water quality were used to develop a conceptual model of chemical evolution of ground water. Stable isotope ratios of deuterium and oxygen-18 in the 33 ground-water samples were similar, indicating similar climatic conditions and source of precipitation recharge for all of the sampled ground water. Oxidation of organic matter and mineral dissolution increased the concentrations of dissolved inorganic carbon and common ions in downgradient ground waters. However, the largest concentrations were not found near areas of ground-water discharge, but at intermediate locations where organic carbon concentrations were greatest. Dissolved methane, derived from microbial methanogenesis, was present in some ground waters. Methanogenesis resulted in substantial alteration of the carbon isotopic composition of ground water. The NETPATH geochemical model code was used to model mass-transfers of carbon affecting the 14C estimate of ground-water residence time. Carbon sources in ground water include dispersed particulate organic matter present in the confining unit separating the two aquifers and methane present in some ground water. Carbonate minerals were not observed in the lithologic material of the ground-water system but may be present, because they have been found in the bedrock of stream drainages that contribute sediment to the study area.
Density Deconvolution With EPI Splines
2015-09-01
effects of various substances on test subjects [11], [12]. Whereas in geophysics, a shot may be fired into the ground, in pharmacokinetics, a signal is...be significant, including medicine, bioinformatics, chemistry, as- tronomy, and econometrics , as well as an extensive review of kernel based methods...demonstrate the effectiveness of our model in simulations motivated by test instances in [32]. We consider an additive measurement model scenario where
Fracture control of ground water flow and water chemistry in a rock aquitard
Eaton, T.T.; Anderson, M.P.; Bradbury, K.R.
2007-01-01
There are few studies on the hydrogeology of sedimentary rock aquitards although they are important controls in regional ground water flow systems. We formulate and test a three-dimensional (3D) conceptual model of ground water flow and hydrochemistry in a fractured sedimentary rock aquitard to show that flow dynamics within the aquitard are more complex than previously believed. Similar conceptual models, based on regional observations and recently emerging principles of mechanical stratigraphy in heterogeneous sedimentary rocks, have previously been applied only to aquifers, but we show that they are potentially applicable to aquitards. The major elements of this conceptual model, which is based on detailed information from two sites in the Maquoketa Formation in southeastern Wisconsin, include orders of magnitude contrast between hydraulic diffusivity (K/Ss) of fractured zones and relatively intact aquitard rock matrix, laterally extensive bedding-plane fracture zones extending over distances of over 10 km, very low vertical hydraulic conductivity of thick shale-rich intervals of the aquitard, and a vertical hydraulic head profile controlled by a lateral boundary at the aquitard subcrop, where numerous surface water bodies dominate the shallow aquifer system. Results from a 3D numerical flow model based on this conceptual model are consistent with field observations, which did not fit the typical conceptual model of strictly vertical flow through an aquitard. The 3D flow through an aquitard has implications for predicting ground water flow and for planning and protecting water supplies. ?? 2007 National Ground Water Association.
XML Flight/Ground Data Dictionary Management
NASA Technical Reports Server (NTRS)
Wright, Jesse; Wiklow, Colette
2007-01-01
A computer program generates Extensible Markup Language (XML) files that effect coupling between the command- and telemetry-handling software running aboard a spacecraft and the corresponding software running in ground support systems. The XML files are produced by use of information from the flight software and from flight-system engineering. The XML files are converted to legacy ground-system data formats for command and telemetry, transformed into Web-based and printed documentation, and used in developing new ground-system data-handling software. Previously, the information about telemetry and command was scattered in various paper documents that were not synchronized. The process of searching and reading the documents was time-consuming and introduced errors. In contrast, the XML files contain all of the information in one place. XML structures can evolve in such a manner as to enable the addition, to the XML files, of the metadata necessary to track the changes and the associated documentation. The use of this software has reduced the extent of manual operations in developing a ground data system, thereby saving considerable time and removing errors that previously arose in the translation and transcription of software information from the flight to the ground system.
ERIC Educational Resources Information Center
Stoecker, Randy
2014-01-01
This article explores how on-the-ground Extension educators interface with higher education service-learning. Most service-learning in Extension has focused on precollege youth and 4-H. When we look at higher education service-learning and Extension in Wisconsin, we see that there is not as much connection as might be expected. County-based…
24 CFR 886.332 - Rehabilitation period.
Code of Federal Regulations, 2010 CFR
2010-04-01
... start of rehabilitation after sales closing. After the execution of the Agreement and the sales closing... Agreement and the sale, or take other appropriate action. (b) Extensions. Although extensions of time may be granted by HUD upon a written request from the owner stating the grounds for the extension, no increases...
Determining Extension's Role in Controversial Issues: Content, Process, Neither, or Both?
ERIC Educational Resources Information Center
Goerlich, Dan; Walker, Martha A.
2015-01-01
Controversial issues offer Extension faculty opportunities to facilitate community dialogue and apply conflict resolution strategies to help communities achieve higher ground. Handled appropriately, the long-term benefits to the community, the Extension organization, and the faculty member of facilitating public issues outweigh the costs. This…
Federal Register 2010, 2011, 2012, 2013, 2014
2012-01-24
... Woodcock Singing Ground Survey AGENCY: Fish and Wildlife Service, Interior. ACTION: Notice; request for... Singing Ground Survey. Service Form Number(s): 3-156. Type of Request: Extension of currently approved... various characteristics of migratory bird populations. The North American Woodcock Singing Ground Survey...
Automated pavement analysis in Missouri using ground penetrating radar
DOT National Transportation Integrated Search
2003-02-01
Current geotechnical procedures for monitoring the condition of roadways are time consuming and can be disruptive to traffic, often requiring extensive invasive procedures (e.g., coring). Ground penetrating radar (GPR) technology offers a methodology...
Three-Dimensional Data Registration Based on Human Perception
2006-01-01
sets. The new algorithm was tested extensively on simulated sensor images in several scenarios key to successful application to autonomous ground...that humans perceive visual images, an assumption of stationarity can be applied to the data sets , with to compensate for any new data...proximity to each other that an assumption of, or preference for , stationarity would require corresponding data in the data sets that is not new
I. R. Burling; R. J. Yokelson; S. K. Akagi; Shawn Urbanski; Cyle Wold; D. W. T. Griffith; T. J. Johnson; J. Reardon; D. R. Weise
2011-01-01
We measured the emission factors for 19 trace gas species and particulate matter (PM2.5) from 14 prescribed fires in chaparral and oak savanna in the southwestern US, as well as conifer forest understory in the southeastern US and Sierra Nevada 5 mountains of California. These are likely the most extensive emission factor field measurements for temperate biomass...
De-mystifying earned value management for ground based astronomy projects, large and small
NASA Astrophysics Data System (ADS)
Norton, Timothy; Brennan, Patricia; Mueller, Mark
2014-08-01
The scale and complexity of today's ground based astronomy projects have justifiably required Principal Investigator's and their project teams to adopt more disciplined management processes and tools in order to achieve timely and accurate quantification of the progress and relative health of their projects. Earned Value Management (EVM) is one such tool. Developed decades ago and used extensively in the defense and construction industries, and now a requirement of NASA projects greater than $20M; EVM has gained a foothold in ground-based astronomy projects. The intent of this paper is to de-mystify EVM by discussing the fundamentals of project management, explaining how EVM fits with existing principles, and describing key concepts every project can use to implement their own EVM system. This paper also discusses pitfalls to avoid during implementation and obstacles to its success. The authors report on their organization's most recent experience implementing EVM for the GMT-Consortium Large Earth Finder (G-CLEF) project. G-CLEF is a fiber-fed, optical echelle spectrograph that has been selected as a first light instrument for the Giant Magellan Telescope (GMT), planned for construction at the Las Campanas Observatory in Chile's Atacama Desert region.
Sleep and vestibular adaptation: implications for function in microgravity
NASA Technical Reports Server (NTRS)
Hobson, J. A.; Stickgold, R.; Pace-Schott, E. F.; Leslie, K. R.
1998-01-01
Optimal human performance depends upon integrated sensorimotor and cognitive functions, both of which are known to be exquisitely sensitive to loss of sleep. Under the microgravity conditions of space flight, adaptation of both sensorimotor (especially vestibular) and cognitive functions (especially orientation) must occur quickly--and be maintained--despite any concurrent disruptions of sleep that may be caused by microgravity itself, or by the uncomfortable sleeping conditions of the spacecraft. It is the three-way interaction between sleep quality, general work efficiency, and sensorimotor integration that is the subject of this paper and the focus of new work in our laboratory. To record sleep under field conditions including microgravity, we utilize a novel system called the Nightcap that we have developed and extensively tested on normal and sleep-disordered subjects. To perturb the vestibular system in ground-based studies, we utilize a variety of experimental conditions including optokinetic stimulation and both minifying and reversing goggle paradigms that have been extensively studied in relation to plasticity of the vestibulo-ocular reflex. Using these techniques we will test the hypothesis that vestibular adaptation both provokes and is enhanced by REM sleep under both ground-based and space conditions. In this paper we describe preliminary results of some of our studies.
Borcherdt, Roger D.
2012-01-01
VS30, defined as the average seismic shear-wave velocity from the surface to a depth of 30 meters, has found wide-spread use as a parameter to characterize site response for simplified earthquake resistant design as implemented in building codes worldwide. VS30 , as initially introduced by the author for the US 1994 NEHRP Building Code, provides unambiguous definitions of site classes and site coefficients for site-dependent response spectra based on correlations derived from extensive borehole logging and comparative ground-motion measurement programs in California. Subsequent use of VS30 for development of strong ground motion prediction equations (GMPEs) and measurement of extensive sets of VS borehole data have confirmed the previous empirical correlations and established correlations of SVS30 with VSZ at other depths. These correlations provide closed form expressions to predict S30 V at a large number of additional sites and further justify S30 V as a parameter to characterize site response for simplified building codes, GMPEs, ShakeMap, and seismic hazard mapping.
EOS situational data shared service mechanism
NASA Astrophysics Data System (ADS)
Lv, L.; Xu, Q.; Lan, C. Z.; Shi, Q. S.; Lu, W. J.; Wu, W. Q.
2016-11-01
With the rapid development of aerospace and remote sensing technology, various high-resolution Earth Observation Systems (EOS) are widely used in economic, social, military and other fields and playing an increasingly prominent role in the construction of Digital Earth and national strategic planning. The normal operation of the system is the premise of high quality data acquisition. Compared with the ground observation mode, EOS itself and the surrounding environment are more complex, and its operation control mainly depends on all kinds of Space Situational Awareness (SSA) data acquisition and analysis. SSA data has more extensive sources, larger volume, stronger time-effectiveness and more complicated structure than traditional geographical spatial data. For effective data sharing and utilization, combined with the analysis of data types and structures, a SSA data sharing identity language SSDSML is designed based on the extensible mark-up language XML, which realizes a comprehensive description of satellites and their attributes, space environment, ground stations, etc. Then EOS situational data shared service mechanism is established and provides a powerful data support for the normal operation of the system.
From Early Exploration to Space Weather Forecasts: Canada's Geomagnetic Odyssey
NASA Astrophysics Data System (ADS)
Lam, Hing-Lan
2011-05-01
Canada is a region ideally suited for the study of space weather: The north magnetic pole is encompassed within its territory, and the auroral oval traverses its vast landmass from east to west. Magnetic field lines link the country directly to the outer magnetosphere. In light of this geographic suitability, it has been a Canadian tradition to install ground monitors to remotely sense the space above Canadian territory. The beginning of this tradition dates back to 1840, when Edward Sabine, a key figure in the “magnetic crusade” to establish magnetic observatories throughout the British Empire in the nineteenth century, founded the first Canadian magnetic observatory on what is now the campus of the University of Toronto, 27 years before the birth of Canada. This observatory, which later became the Toronto Magnetic and Meteorological Observatory, marked the beginning of the Canadian heritage of installing magnetic stations and other ground instruments in the years to come. This extensive network of ground-based measurement devices, coupled with space-based measurements in more modern times, has enabled Canadian researchers to contribute significantly to studies related to space weather.
NASA Technical Reports Server (NTRS)
Bruegman, Otto; Thakore, Kamal; Loewenthal, Stu; Cymerman, John
2016-01-01
The Advanced Technology Microwave Sounder (ATMS) instrument scan system on the Suomi National Polar-orbiting Partnership (SNPP) spacecraft has experienced several randomly occurring increased torque 'events' since its on-orbit activation in November 2011. Based on a review of on-orbit telemetry data and data gathered from scan mechanism bearing life testing on the ground, the conclusion was drawn that some degradation of Teflon toroid ball retainers was occurring in the instrument Scan Drive Mechanism. A life extension program was developed and executed on-orbit with very good results to date. The life extension program consisted of reversing the mechanism for a limited number of consecutive scans every day.
Recognition of surface lithologic and topographic patterns in southwest Colorado with ADP techniques
NASA Technical Reports Server (NTRS)
Melhorn, W. N.; Sinnock, S.
1973-01-01
Analysis of ERTS-1 multispectral data by automatic pattern recognition procedures is applicable toward grappling with current and future resource stresses by providing a means for refining existing geologic maps. The procedures used in the current analysis already yield encouraging results toward the eventual machine recognition of extensive surface lithologic and topographic patterns. Automatic mapping of a series of hogbacks, strike valleys, and alluvial surfaces along the northwest flank of the San Juan Basin in Colorado can be obtained by minimal man-machine interaction. The determination of causes for separable spectral signatures is dependent upon extensive correlation of micro- and macro field based ground truth observations and aircraft underflight data with the satellite data.
Space Link Extension Protocol Emulation for High-Throughput, High-Latency Network Connections
NASA Technical Reports Server (NTRS)
Tchorowski, Nicole; Murawski, Robert
2014-01-01
New space missions require higher data rates and new protocols to meet these requirements. These high data rate space communication links push the limitations of not only the space communication links, but of the ground communication networks and protocols which forward user data to remote ground stations (GS) for transmission. The Consultative Committee for Space Data Systems, (CCSDS) Space Link Extension (SLE) standard protocol is one protocol that has been proposed for use by the NASA Space Network (SN) Ground Segment Sustainment (SGSS) program. New protocol implementations must be carefully tested to ensure that they provide the required functionality, especially because of the remote nature of spacecraft. The SLE protocol standard has been tested in the NASA Glenn Research Center's SCENIC Emulation Lab in order to observe its operation under realistic network delay conditions. More specifically, the delay between then NASA Integrated Services Network (NISN) and spacecraft has been emulated. The round trip time (RTT) delay for the continental NISN network has been shown to be up to 120ms; as such the SLE protocol was tested with network delays ranging from 0ms to 200ms. Both a base network condition and an SLE connection were tested with these RTT delays, and the reaction of both network tests to the delay conditions were recorded. Throughput for both of these links was set at 1.2Gbps. The results will show that, in the presence of realistic network delay, the SLE link throughput is significantly reduced while the base network throughput however remained at the 1.2Gbps specification. The decrease in SLE throughput has been attributed to the implementation's use of blocking calls. The decrease in throughput is not acceptable for high data rate links, as the link requires constant data a flow in order for spacecraft and ground radios to stay synchronized, unless significant data is queued a the ground station. In cases where queuing the data is not an option, such as during real time transmissions, the SLE implementation cannot support high data rate communication.
NASA Technical Reports Server (NTRS)
Hou, Arthur Y.
2011-01-01
A major challenge in understanding the space-time variability of continental water fluxes is the lack of accurate precipitation estimates over complex terrains. While satellite precipitation observations can be used to complement ground-based data to obtain improved estimates, space-based and ground-based estimates come with their own sets of uncertainties, which must be understood and characterized. Quantitative estimation of uncertainties in these products also provides a necessary foundation for merging satellite and ground-based precipitation measurements within a rigorous statistical framework. Global Precipitation Measurement (GPM) is an international satellite mission that will provide next-generation global precipitation data products for research and applications. It consists of a constellation of microwave sensors provided by NASA, JAXA, CNES, ISRO, EUMETSAT, DOD, NOAA, NPP, and JPSS. At the heart of the mission is the GPM Core Observatory provided by NASA and JAXA to be launched in 2013. The GPM Core, which will carry the first space-borne dual-frequency radar and a state-of-the-art multi-frequency radiometer, is designed to set new reference standards for precipitation measurements from space, which can then be used to unify and refine precipitation retrievals from all constellation sensors. The next-generation constellation-based satellite precipitation estimates will be characterized by intercalibrated radiometric measurements and physical-based retrievals using a common observation-derived hydrometeor database. For pre-launch algorithm development and post-launch product evaluation, NASA supports an extensive ground validation (GV) program in cooperation with domestic and international partners to improve (1) physics of remote-sensing algorithms through a series of focused field campaigns, (2) characterization of uncertainties in satellite and ground-based precipitation products over selected GV testbeds, and (3) modeling of atmospheric processes and land surface hydrology through simulation, downscaling, and data assimilation. An overview of the GPM mission, science status, and synergies with HyMex activities will be presented
NASA Astrophysics Data System (ADS)
Taylor, M. J.; Zhao, Y.; Pautet, P. D.; Carstens, J. N.; Pugmire, J. R.; Smith, S. M.; Liu, A. Z.; Vargas, F.; Swenson, G. R.; Randall, C. E.; Bailey, S. M.; Russell, J. M., III
2016-12-01
To date, the primary research goals of the Aeronomy of Ice in the Mesosphere (AIM) satellite have focussed on investigating the occurrence, properties and dynamics of high-latitude Polar Mesospheric Clouds (PMC). With the evolution of the AIM orbit beta angle the opportunity now exists to make measurements outside the PMC region covering mid-low and equatorial latitudes. As part of the extended AIM mission science program, the AIM platform in conjunction with auxiliary ground-based measurements will be used to better understand upper atmospheric dynamics and vertical coupling due to gravity waves. Over the next 2 years AIM will take advantage of a new imaging capability of the on-board large-field CIPS UV imager to capture new data on the characteristics and spatial extents of stratospheric gravity waves near the 50 km level and their variation with latitude and season. In this study we report on initial coordinated ground-based measurements with the Andes Lidar Observatory (ALO) at Cerro Pachon, Chile ( 30°S) and nearby El Leoncito Observatory, Argentina, high in the Andes Mountains, where regular remote-sensing measurements are made using meteor radar, mesospheric airglow imagers, temperature mappers and an Na wind-temperature lidar (on a campaign basis). First coordinated measurements were made during the winter period in June 2016. AIM daytime overpasses have been analysed to search for and characterize extensive stratospheric wave events, as well as long-lived "Mountain Waves" over South America. Subsequent night-time ground-based measurements have been used to quantify wave characteristics in the mesopause region ( 80-100 km) to investigate vertical coupling. These measurements are continuing and it is planned to extend the new AIM stratospheric gravity wave data set for similar studies from a number of well-instrumented ground sites around the world.
NASA Astrophysics Data System (ADS)
Silva, Guilherme Gregório; Mura, José Claudio; Paradella, Waldir Renato; Gama, Fabio Furlan; Temporim, Filipe Altoé
2017-04-01
Persistent scatterer interferometry (PSI) analysis of a large area is always a challenging task regarding the removal of the atmospheric phase component. This work presents an investigation of ground movement measurements based on a combination of differential SAR interferometry time-series (DTS) and PSI techniques, applied on a large area of extent with open pit iron mines located in Carajás (Brazilian Amazon Region), aiming at detecting linear and nonlinear ground movement. These mines have presented a history of instability, and surface monitoring measurements over sectors of the mines (pit walls) have been carried out based on ground-based radar and total station (prisms). Using a priori information regarding the topographic phase error and a phase displacement model derived from DTS, temporal phase unwrapping in the PSI processing and the removal of the atmospheric phases can be performed more efficiently. A set of 33 TerraSAR-X (TSX-1) images, acquired during the period from March 2012 to April 2013, was used to perform this investigation. The DTS analysis was carried out on a stack of multilook unwrapped interferograms using an extension of SVD to obtain the least-square solution. The height errors and deformation rates provided by the DTS approach were subtracted from the stack of interferograms to perform the PSI analysis. This procedure improved the capability of the PSI analysis for detecting high rates of deformation, as well as increased the numbers of point density of the final results. The proposed methodology showed good results for monitoring surface displacement in a large mining area, which is located in a rain forest environment, providing very useful information about the ground movement for planning and risk control.
MERI: an ultra-long-baseline Moon-Earth radio interferometer.
NASA Astrophysics Data System (ADS)
Burns, J. O.
Radiofrequency aperture synthesis, pioneered by Ryle and his colleagues at Cambridge in the 1960's, has evolved to ever longer baselines and larger arrays in recent years. The limiting resolution at a given frequency for modern ground-based very-long-baseline interferometry is simply determined by the physical diameter of the Earth. A second-generation, totally space-based VLB network was proposed recently by a group at the Naval Research Laboratory. The next logical extension of space-based VLBI would be a station or stations on the Moon. The Moon could serve as an outpost or even the primary correlator station for an extended array of space-based antennas.
Detecting Target Objects by Natural Language Instructions Using an RGB-D Camera
Bao, Jiatong; Jia, Yunyi; Cheng, Yu; Tang, Hongru; Xi, Ning
2016-01-01
Controlling robots by natural language (NL) is increasingly attracting attention for its versatility, convenience and no need of extensive training for users. Grounding is a crucial challenge of this problem to enable robots to understand NL instructions from humans. This paper mainly explores the object grounding problem and concretely studies how to detect target objects by the NL instructions using an RGB-D camera in robotic manipulation applications. In particular, a simple yet robust vision algorithm is applied to segment objects of interest. With the metric information of all segmented objects, the object attributes and relations between objects are further extracted. The NL instructions that incorporate multiple cues for object specifications are parsed into domain-specific annotations. The annotations from NL and extracted information from the RGB-D camera are matched in a computational state estimation framework to search all possible object grounding states. The final grounding is accomplished by selecting the states which have the maximum probabilities. An RGB-D scene dataset associated with different groups of NL instructions based on different cognition levels of the robot are collected. Quantitative evaluations on the dataset illustrate the advantages of the proposed method. The experiments of NL controlled object manipulation and NL-based task programming using a mobile manipulator show its effectiveness and practicability in robotic applications. PMID:27983604
Framework for a ground-water quality monitoring and assessment program for California
Belitz, Kenneth; Dubrovsky, Neil M.; Burow, Karen; Jurgens, Bryant C.; John, Tyler
2003-01-01
The State of California uses more ground water than any other State in the Nation. With a population of over 30 million people, an agricultural economy based on intensive irrigation, large urban industrial areas, and naturally elevated concentrations of some trace elements, there is a wide range of contaminant sources that have the potential to contaminate ground water and limit its beneficial uses. In response to the many-and different-potential sources of ground-water contamination, the State of California has evolved an extensive set of rules and programs to protect ground-water quality, and agencies to implement the rules and programs. These programs have in common a focus on compliance with regulations governing chemical use and (or) ground-water quality. Although appropriate for, and successful at, their specific missions, these programs do not at present provide a comprehensive view of ground-water quality in the State of California. In October 2001, The California Assembly passed a bill, AB 599, establishing the Ground-Water- Quality Monitoring Act of 2001.' The goal of AB 599 is to improve Statewide comprehensive ground-water monitoring and increase availability of information about ground-water quality to the public. AB 599 requires the State Water Resources Control Board (SWRCB), in collaboration with an interagency task force (ITF) and a public advisory committee (PAC), to develop a plan for a comprehensive ground-water monitoring program. AB 599 specifies that the comprehensive program should be capable of assessing each ground-water basin in the State through direct and other statistically reliable sampling approaches, and that the program should integrate existing monitoring programs and design new program elements, as necessary. AB 599 also stresses the importance of prioritizing ground-water basins that provide drinking water. The United States Geological Survey (USGS), in cooperation with the SWRCB, and in coordination with the ITF and PAC, has developed a framework for a comprehensive ground-water-quality monitoring and assessment program for California. The proposed framework relies extensively on previous work conducted by the USGS through its National Water-Quality Assessment (NAWQA) program. In particular, the NAWQA program defines three types of ground-water assessment: (1) status, the assessment of the current quality of the ground-water resource; (2) trends, the detection of changes in water quality, and (3) understanding, assessing the human and natural factors that affect ground-water quality. A Statewide, comprehensive ground-water quality-monitoring and assessment program is most efficiently accomplished by applying uniform and consistent study-design and data-collection protocols to the entire State. At the same time, a comprehensive program should be relevant at a variety of scales, and therefore needs to retain flexibility to address regional and local issues. Consequently, many of the program components include a predominant element that will be consistently applied in all basins, and a secondary element that may be applied in specific basins where local conditions warrant attention.
Some far-field acoustics characteristics of the XV-15 tilt-rotor aircraft
NASA Technical Reports Server (NTRS)
Golub, Robert A.; Conner, David A.; Becker, Lawrence E.; Rutledge, C. Kendall; Smith, Rita A.
1990-01-01
Far-field acoustics tests have been conducted on an instrumented XV-15 tilt-rotor aircraft. The purpose of these acoustic measurements was to create an encompassing, high confidence (90 percent), and accurate (-1.4/ +1/8 dB theoretical confidence interval) far-field acoustics data base to validate ROTONET and other current rotorcraft noise prediction computer codes. This paper describes the flight techniques used, with emphasis on the care taken to obtain high-quality far-field acoustic data. The quality and extensiveness of the data base collected are shown by presentation of ground acoustic contours for level flyovers for the airplane flight mode and for several forward velocities and nacelle tilts for the transition mode and helicopter flight mode. Acoustic pressure time-histories and fully analyzed ensemble averaged far-field data results (spectra) are shown for each of the ground contour cases.
Extending Cancer Prevention to Improve Fruit and Vegetable Consumption
Freedman, Darcy A.; Peña-Purcell, Ninfa; Friedman, Daniela B.; Ory, Marcia; Flocke, Susan; Barni, Marie T.; Hébert, James R.
2014-01-01
Consuming a diet that is rich in fruits and vegetables is critical for preventing cancer and cancer-related disparities. Food systems approaches that increase spatial-temporal, economic, and social access to fruits and vegetables may ultimately result in improved consumption patterns among Americans. Engaging the triad of Cooperative Extension Services, public health systems, and community health centers may yield maximal public health benefits from food systems interventions. These entities have a mutual interest in promoting health equity and community and economic vitality that provides common ground to (a) implement solutions through the dissemination of evidence-based programs and (b) share resources to foster grassroots support for sustained change. Working together, these systems have an unprecedented opportunity to build on their common ground to implement, evaluate, and disseminate evidence-based food systems interventions in communities and with populations experiencing disparate risk for cancer and cancer-related diseases. PMID:24748060
DOE Office of Scientific and Technical Information (OSTI.GOV)
Jensen, Michael; Kollias, Pavlos; Giangrande, Scott
The Mid-latitude Continental Convective Clouds Experiment (MC3E) took place from April 22 through June 6, 2011, centered at the ARM Southern Great Plains site (http://www.arm.gov/sites/sgp) in northcentral Oklahoma. MC3E was a collaborative effort between the ARM Climate Research Facility and the National Aeronautics and Space Administration’s (NASA’s) Global Precipitation Measurement (GPM) mission Ground Validation (GV) program. The campaign leveraged the largest ground-based observing infrastructure available in the central United States, including recent upgrades through the American Recovery and Reinvestment Act of 2009, combined with an extensive sounding array, remote sensing and in situ aircraft observations, and additional radar and inmore » situ precipitation instrumentation. The overarching goal of the campaign was to provide a three-dimensional characterization of convective clouds and precipitation for the purpose of improving the representation of convective lifecycle in atmospheric models and the reliability of satellite-based retrievals of precipitation.« less
Determining the amount of soilborne inoculum of Phytophthora ramorum within an Oregon tanoak forest
Christina Benemann; Jennifer Parke
2017-01-01
Phytophthora ramorum continues to cause extensive mortality of tanoaks in southwestern Oregon. Effective management strategies have been developed based on our current understanding of the pathogenâs epidemiology. Local dispersal can occur either by canopy throughfall (âtop-downâ) or a ground splash (âbottom-upâ) pathway. Although the âtop...
GWVis: A Tool for Comparative Ground-Water Data Visualization
DOE Office of Scientific and Technical Information (OSTI.GOV)
Best, Daniel M.; Lewis, Robert R.
2010-11-01
The Ground-Water Visualization application (GWVis) presents ground-water data visually in order to educate the public on ground-water issues. It is also intended for presentations to government and other funding agencies. Current three dimensional models of ground-water are overly complex, while the two dimensional representations (i.e., on paper) are neither comprehensive, nor engaging. At present, GWVis operates on water head elevation data over a given time span, together with a matching (fixed) underlying geography. Two elevation scenarios are compared with each other, typically a control data set (actual field data) and a simulation. Scenario comparison can be animated for the timemore » span provided. We developed GWVis using the Python programming language, associated libraries, and pyOpenGL extension packages to improve performance and control of attributes of the mode (such as color, positioning, scale, and interpolation). GWVis bridges the gap between two dimensional and dynamic three dimensional research visualizations by providing an intuitive, interactive design that allows participants to view the model from different perspectives and to infer information about scenarios. By incorporating scientific data in an environment that can be easily understood, GWVis allows the information to be presented to a large audience base.« less
Research in millimeter wave techniques
NASA Technical Reports Server (NTRS)
Mcmillan, R. W.
1978-01-01
During the past six months, efforts on this project have been devoted to: (1) continuation of construction and testing of a 6 GHz subharmonic mixer model with extension of the pumping frequency of this mixer to omega sub s/4, (2) construction of a 183 GHz subharmonic mixer based on the results of tests on this 6 GHz model, (3) ground-based radiometric measurements at 183 GHz, (4) fabrication and testing of wire grid interferometers, (5) calculations of reflected and lost power in these interferometers, and (6) calculations of the antenna temperature due to water vapor to be expected in down-looking radiometry as a function of frequency. Significant events during the past six months include: (1) Receipt of a 183 GHz single-ended fundamental mixer, (2) attainment of 6 db single sideband conversion loss with the 6 GHz subharmonic mixer model by using a 1.5 GHz (omega sub s/4) pump frequency, (3) additional ground-based radiometric measurements and (4) derivation of equations for reflection and loss for wire grid interferometers.
NASA Technical Reports Server (NTRS)
Turflinger, T.; Schmeichel, W.; Krieg, J.; Titus, J.; Campbell, A.; Reeves, M.; Marshall (P.); Hardage, Donna (Technical Monitor)
2004-01-01
This effort is a detailed analysis of existing microelectronics and photonics test bed satellite data from one experiment, the bipolar test board, looking to improve our understanding of the enhanced low dose rate sensitivity (ELDRS) phenomenon. Over the past several years, extensive total dose irradiations of bipolar devices have demonstrated that many of these devices exhibited ELDRS. In sensitive bipolar transistors, ELDRS produced enhanced degradation of base current, resulting in enhanced gain degradation at dose rates <0.1 rd(Si)/s compared to similar transistors irradiated at dose rates >1 rd(Si)/s. This Technical Publication provides updated information about the test devices, the in-flight experiment, and both flight-and ground-based observations. Flight data are presented for the past 5 yr of the mission. These data are compared to ground-based data taken on devices from the same date code lots. Information about temperature fluctuations, power shutdowns, and other variables encountered during the space flight are documented.
Interior view, groundfloor dining hall extending across the rotunda extension ...
Interior view, ground-floor dining hall extending across the rotunda extension from it's northern exterior wall to its southern exterior wall, from the north. - U. S. Naval Asylum, Biddle Hall, Gray's Ferry Avenue, Philadelphia, Philadelphia County, PA
Video requirements for materials processing experiments in the space station US laboratory
NASA Technical Reports Server (NTRS)
Baugher, Charles R.
1989-01-01
Full utilization of the potential of the materials research on the Space Station can be achieved only if adequate means are available for interactive experimentation between the science facilities and ground-based investigators. Extensive video interfaces linking these three elements are the only alternative for establishing a viable relation. Because of the limit in the downlink capability, a comprehensive complement of on-board video processing, and video compression is needed. The application of video compression will be an absolute necessity since it's effectiveness will directly impact the quantity of data which will be available to ground investigator teams, and their ability to review the effects of process changes and the experiment progress. Video data compression utilization on the Space Station is discussed.
Validation of Ground-based Optical Estimates of Auroral Electron Precipitation Energy Deposition
NASA Astrophysics Data System (ADS)
Hampton, D. L.; Grubbs, G. A., II; Conde, M.; Lynch, K. A.; Michell, R.; Zettergren, M. D.; Samara, M.; Ahrns, M. J.
2017-12-01
One of the major energy inputs into the high latitude ionosphere and mesosphere is auroral electron precipitation. Not only does the kinetic energy get deposited, the ensuing ionization in the E and F-region ionosphere modulates parallel and horizontal currents that can dissipate in the form of Joule heating. Global models to simulate these interactions typically use electron precipitation models that produce a poor representation of the spatial and temporal complexity of auroral activity as observed from the ground. This is largely due to these precipitation models being based on averages of multiple satellite overpasses separated by periods much longer than typical auroral feature durations. With the development of regional and continental observing networks (e.g. THEMIS ASI), the possibility of ground-based optical observations producing quantitative estimates of energy deposition with temporal and spatial scales comparable to those known to be exhibited in auroral activity become a real possibility. Like empirical precipitation models based on satellite overpasses such optics-based estimates are subject to assumptions and uncertainties, and therefore require validation. Three recent sounding rocket missions offer such an opportunity. The MICA (2012), GREECE (2014) and Isinglass (2017) missions involved detailed ground based observations of auroral arcs simultaneously with extensive on-board instrumentation. These have afforded an opportunity to examine the results of three optical methods of determining auroral electron energy flux, namely 1) ratio of auroral emissions, 2) green line temperature vs. emission altitude, and 3) parametric estimates using white-light images. We present comparisons from all three methods for all three missions and summarize the temporal and spatial scales and coverage over which each is valid.
The Kepler Mission: From Concept to Operations
NASA Astrophysics Data System (ADS)
Koch, David G.
2011-01-01
From concept to launch and operations, what became the Kepler mission took a quarter of a century to create. We will review some of the steps along the way, the challenges, opportunities, strategic decisions and choices that had to be made that resulted in a mission that has the capability to detect and determine the frequencies of Earth-size planets in or near the habitable zone of solar-like stars. The process of going from starlight focused onto individual pixels to declaration of a planet detection is long and complex. Data for each star are recorded on the spacecraft and telemetered to the ground once per month. The raw pixel data are processed to produce light curves for each star. The light curves are processed to search for sequences of transits. A team of scientists examines the output to decide which meet the many validation criteria and qualify as candidates. Next an extensive series of ground-based follow-up observations are performed on the candidates now numbering in excess of 700. The objective is to eliminate false positive cases, while simultaneously improving our knowledge of the parent stars. Extensive analysis and modeling is performed on both the original photometric data and the newly acquired ground-based data to ascertain the true nature of each candidate. On the order of one-quarter to one-half of the candidates are rejected, mostly as some form of eclipsing binary. Of the remaining, some meet all the criteria and are submitted by the science team for peer-reviewed publications. Others may just require more data or may be left as undecided candidates for future research. An extended mission beyond 3.5 years will significantly improve the results from the Kepler mission, especially by covering the outer portion of the habitable zone for solar-like stars.
Mountain Permafrost in the Yukon Territory, Canada: Mapping and Modelling
NASA Astrophysics Data System (ADS)
Lewkowicz, A. G.; Bonnaventure, P.; Schultz, E.; Etzelmuller, B.
2006-12-01
The distribution and characteristics of mountain permafrost in North America are poorly known compared to lowland permafrost, and predictions of climatic change impacts are therefore subject to a higher degree of uncertainty. Recent DC resistivity soundings in association with borehole temperature information in the Yukon Territory, show the wide range of permafrost conditions that can exist at sites separated by short distances. To provide baseline information for future modelling, efforts are underway to produce a detailed map of permafrost probability in the mountains of the southern half of the Yukon Territory (60-65°N), an area greater than 200 x 103km2. The methodology is based on the Basal Temperature of Snow (BTS) technique, first developed in the European Alps. Ground surface temperatures measured at the base of snow > 80 cm thick in late winter are an indicator of permafrost presence or absence. We have used this method successfully in three study areas of about 200 km2: first, Wolf Creek basin near Whitehorse (Lewkowicz and Ednie, 2004) and now the western side of the Ruby Range adjacent to Kluane Lake, and the Haines Summit area in northwestern British Columbia. In each area, (1) we installed miniature temperature loggers at the ground surface and in the air to check on the timing of the BTS measurements; (2) we measured BTS values in the elevation zone across which permafrost was expected to become widespread; (3) we modelled the BTS spatial field using elevation (from a 30 m DEM) and potential incoming solar radiation (PISR) as the independent variables; and (4) we used logistic regression to compare the modelled BTS values with pit observations made in late-summer of the presence or absence of frozen ground. Both elevation and PISR were significant in the Wolf Creek and Ruby Range sites which have relatively continental climates and fall within the Upper Yukon-Stikine Basin climatic region (Wahl et al., 1987). For the Haines Summit area, however, PISR was not significant, likely reflecting the much more maritime climate of this area and the frequent fogs that are present. More than 50 new air and ground temperature monitoring stations were installed in spring 2006 as the first step to extend the modelling to the remaining mountainous parts of the Yukon Territory. We selected sites within the four climatic regions encompassing discontinuous permafrost that we had not previously sampled: the Faro area (Central Yukon Basin region, extensive discontinuous zone), Johnson's Crossing (Pelly-Cassiar Mountains region, sporadic discontinuous zone), Sa Dena Hes mine (Liard Basin region, extensive discontinuous zone) and the Keno area (Ogilvie-Mackenzie Mountains region, extensive discontinuous zone). Each of the stations is equipped to measure air temperature, ground surface temperature, ground temperature at a depth of 1 m (to evaluate the thermal offset), and snow depth (interpreted from I-button miniature loggers installed on a stake). These measurements will not only be used for permafrost modelling but will generate a unique data-set of air and ground surface temperatures which will be employed to investigate the frequency of air temperature inversions, their relation to topography and their effect on permafrost. The first complete monthly results (July 2006) demonstrate the expected wide variability in air and ground surface temperatures at both regional and local scales that makes modelling mountain permafrost so challenging.
Launch Method for Kites in Low-Wind or No-Wind Conditions
NASA Technical Reports Server (NTRS)
Bland, Geoffrey; Miles, Ted
2012-01-01
Airborne observations using lightweight camera systems are desirable for a variety of applications. This system was contemplated as a method to provide a simple remote sensing aerial platform. Kites have been successfully employed for aerial observations, but have historically required natural wind or towing to become airborne. This new method negates this requirement, and widens the applicability of kites for carrying instrumentation. Applicability is primarily limited by the space available on the ground for launching. The innovation is a method for launching kites in low-wind or no-wind conditions. This method will enable instrumentation to be carried aloft using simple (or complex) kite-based systems, to obtain observations from an aerial perspective. This technique will provide access to altitudes of 100 meters or more over any area normally suited for kite flying. The duration of any observation is dependent on wind strength; however, the initial altitude is relatively independent. The system does not require any electrical or combustion-based elements. This technology was developed to augment local-scale airborne measurement capabilities suitable for Earth science research, agricultural productivity, and environmental observations. The method represents an extension of techniques often used in aeronautical applications for launching fixed-wing aircraft, such as sailplanes, using mechanical means not incorporated in the aircraft itself. The innovation consists of an elastic cord (for propulsive force), a tether extension (optional, for additional height), and the kite (instrumentation optional). Operation of the system is accomplished by fixing the elastic cord to ground (or equivalent), attaching the cord with/or without a tether extension to the kite, tensioning the system to store energy, and releasing the kite. The kite will climb until energy is dissipated.
NASA Astrophysics Data System (ADS)
Yin, G.; Forman, B. A.; Loomis, B. D.; Luthcke, S. B.
2017-12-01
Vertical deformation of the Earth's crust due to the movement and redistribution of terrestrial freshwater can be studied using satellite measurements, ground-based sensors, hydrologic models, or a combination thereof. This current study explores the relationship between vertical deformation estimates derived from mass concentrations (mascons) from the Gravity Recovery and Climate Experiment (GRACE), vertical deformation from ground-based Global Positioning System (GPS) observations collected from the Plate Boundary Observatory (PBO), and hydrologic loading estimates based on model output from the NASA Catchment Land Surface Model (Catchment). A particular focus is made to snow-dominated basins where mass accumulates during the snow season and subsequently runs off during the ablation season. The mean seasonal cycle and the effects of atmospheric loading, non-tidal ocean loading, and glacier isostatic adjustment (GIA) are removed from the GPS observations in order to derive the vertical displacement caused predominately by hydrological processes. A low-pass filter is applied to GPS observations to remove high frequency noise. Correlation coefficients between GRACE- and GPS-based estimates at all PBO sites are calculated. GRACE-derived and Catchment-derived displacements are subtracted from the GPS height variations, respectively, in order to compute the root mean square (RMS) reduction as a means of studying the consistency between the three different methods. Results show that in most sites, the three methods exhibit good agreement. Exceptions to this generalization include the Central Valley of California where extensive groundwater pumping is witnessed in the GRACE- and GPS-based estimates, but not in the Catchment-based estimates because anthropogenic groundwater pumping activities are not included in the Catchment model. The relatively good agreement between GPS- and GRACE-derived vertical crustal displacements suggests that ground-based GPS has tremendous potential for a Bayesian merger with GRACE-based estimates in order to provide a higher resolution (in space and time) of terrestrial water storage.
Effects of timber size-class on predation of artificial nests in extensive forest
Richard M. DeGraaf; Per Angelstam
1993-01-01
Depredation on artificial ground and cup nests in even-aged seedling/sapling, pole, and mature stands of continuous northern hardwood forest was studied in the White Mountain National Forest in New Hampshire, USA from May to June 1988. Track-board nests were used to identify predators of ground nests; plain ground nests and cup nests were used to investigate the...
NASA Technical Reports Server (NTRS)
1979-01-01
The functional, performance, design, and test requirements for the Orbiter power extension package and its associated ground support equipment are defined. Both government and nongovernment standards and specifications are cited for the following subsystems: electrical power, structural/mechanical, avionics, and thermal control. Quality control assurance provisions and preparation for delivery are also discussed.
Networked high-speed auroral observations combined with radar measurements for multi-scale insights
NASA Astrophysics Data System (ADS)
Hirsch, M.; Semeter, J. L.
2015-12-01
Networks of ground-based instruments to study terrestrial aurora for the purpose of analyzing particle precipitation characteristics driving the aurora have been established. Additional funding is pouring into future ground-based auroral observation networks consisting of combinations of tossable, portable, and fixed installation ground-based legacy equipment. Our approach to this problem using the High Speed Tomography (HiST) system combines tightly-synchronized filtered auroral optical observations capturing temporal features of order 10 ms with supporting measurements from incoherent scatter radar (ISR). ISR provides a broader spatial context up to order 100 km laterally on one minute time scales, while our camera field of view (FOV) is chosen to be order 10 km at auroral altitudes in order to capture 100 m scale lateral auroral features. The dual-scale observations of ISR and HiST fine-scale optical observations may be coupled through a physical model using linear basis functions to estimate important ionospheric quantities such as electron number density in 3-D (time, perpendicular and parallel to the geomagnetic field).Field measurements and analysis using HiST and PFISR are presented from experiments conducted at the Poker Flat Research Range in central Alaska. Other multiscale configuration candidates include supplementing networks of all-sky cameras such as THEMIS with co-locations of HiST-like instruments to fuse wide FOV measurements with the fine-scale HiST precipitation characteristic estimates. Candidate models for this coupling include GLOW and TRANSCAR. Future extensions of this work may include incorporating line of sight total electron count estimates from ground-based networks of GPS receivers in a sensor fusion problem.
Jenkins, J M; Doyle, L R; Cullers, D K
1996-02-01
The photometric detection of extrasolar planets by transits in eclipsing binary systems can be significantly improved by cross-correlating the observational light curves with synthetic models of possible planetary transit features, essentially a matched filter approach. We demonstrate the utility and application of this transit detection algorithm for ground-based detections of terrestrial-sized (Earth-to-Neptune radii) extrasolar planets in the dwarf M-star eclipsing binary system CM Draconis. Preliminary photometric observational data of this system demonstrate that the observational noise is well characterized as white and Gaussian at the observational time steps required for precision photometric measurements. Depending on planet formation scenarios, terrestrial-sized planets may form quite close to this low-luminosity system. We demonstrate, for example, that planets as small as 1.4 Earth radii with periods on the order of a few months in the CM Draconis system could be detected at the 99.9% confidence level in less than a year using 1-m class telescopes from the ground. This result contradicts commonly held assumptions limiting present ground-based efforts to, at best, detections of gas giant planets after several years of observation. This method can be readily extended to a number of other larger star systems with the utilization of larger telescopes and longer observing times. Its extension to spacecraft observations should also allow the determination of the presence of terrestrial-sized planets in nearly 100 other known eclipsing binary systems.
NASA Technical Reports Server (NTRS)
Jenkins, J. M.; Doyle, L. R.; Cullers, D. K.
1996-01-01
The photometric detection of extrasolar planets by transits in eclipsing binary systems can be significantly improved by cross-correlating the observational light curves with synthetic models of possible planetary transit features, essentially a matched filter approach. We demonstrate the utility and application of this transit detection algorithm for ground-based detections of terrestrial-sized (Earth-to-Neptune radii) extrasolar planets in the dwarf M-star eclipsing binary system CM Draconis. Preliminary photometric observational data of this system demonstrate that the observational noise is well characterized as white and Gaussian at the observational time steps required for precision photometric measurements. Depending on planet formation scenarios, terrestrial-sized planets may form quite close to this low-luminosity system. We demonstrate, for example, that planets as small as 1.4 Earth radii with periods on the order of a few months in the CM Draconis system could be detected at the 99.9% confidence level in less than a year using 1-m class telescopes from the ground. This result contradicts commonly held assumptions limiting present ground-based efforts to, at best, detections of gas giant planets after several years of observation. This method can be readily extended to a number of other larger star systems with the utilization of larger telescopes and longer observing times. Its extension to spacecraft observations should also allow the determination of the presence of terrestrial-sized planets in nearly 100 other known eclipsing binary systems.
Fracture control of ground water flow and water chemistry in a rock aquitard.
Eaton, Timothy T; Anderson, Mary P; Bradbury, Kenneth R
2007-01-01
There are few studies on the hydrogeology of sedimentary rock aquitards although they are important controls in regional ground water flow systems. We formulate and test a three-dimensional (3D) conceptual model of ground water flow and hydrochemistry in a fractured sedimentary rock aquitard to show that flow dynamics within the aquitard are more complex than previously believed. Similar conceptual models, based on regional observations and recently emerging principles of mechanical stratigraphy in heterogeneous sedimentary rocks, have previously been applied only to aquifers, but we show that they are potentially applicable to aquitards. The major elements of this conceptual model, which is based on detailed information from two sites in the Maquoketa Formation in southeastern Wisconsin, include orders of magnitude contrast between hydraulic diffusivity (K/S(s)) of fractured zones and relatively intact aquitard rock matrix, laterally extensive bedding-plane fracture zones extending over distances of over 10 km, very low vertical hydraulic conductivity of thick shale-rich intervals of the aquitard, and a vertical hydraulic head profile controlled by a lateral boundary at the aquitard subcrop, where numerous surface water bodies dominate the shallow aquifer system. Results from a 3D numerical flow model based on this conceptual model are consistent with field observations, which did not fit the typical conceptual model of strictly vertical flow through an aquitard. The 3D flow through an aquitard has implications for predicting ground water flow and for planning and protecting water supplies.
The ontogeny of kin-recognition mechanisms in Belding's ground squirrels.
Mateo, Jill M
2017-05-01
Despite extensive research on the functions and mechanisms of kin recognition, little is known about developmental changes in the abilities mediating such recognition. Belding's ground squirrels, Urocitellus beldingi, use at least two mechanisms of kin recognition in nepotistic contexts: familiarity and phenotype matching. Because recognition templates develop from early associations with familiar kin (and/or with self), familiarity-based recognition should precede phenotype-matching recognition even though one template is thought to be used for both mechanisms. I used a cross-fostering design to produce individuals that differed in relatedness and familiarity. Two pups (one female and one male) were exchanged reciprocally between two litters within 48-h of birth. Every five days, from 15 to 30-d of age, young were exposed to bedding and oral-gland odors from their familiar foster mother and an unfamiliar unrelated female (familiarity test) and from their unfamiliar genetic mother and another unfamiliar unrelated female (phenotype-matching test). As expected, discrimination of odors based on familiarity was evident at all ages tested, whereas discrimination based on relatedness was not evident until 30-d. My results provide a first estimate for when phenotype-matching mechanisms are used by young Belding's ground squirrels, and thus when they can recognize unfamiliar kin such as older sisters or grandmothers. Belding's ground squirrels are the first species for which the development of the production, perception and action components is well understood. Copyright © 2017 Elsevier Inc. All rights reserved.
Crystal Growth of ZnSe and Related Ternary Compound Semiconductors by Vapor Transport in Low Gravity
NASA Technical Reports Server (NTRS)
Su, Ching-Hua; Ramachandran, N.
2013-01-01
Crystals of ZnSe and related ternary compounds, such as ZnSeS and ZnSeTe, will be grown by physical vapor transport in the Material Science Research Rack (MSRR) on International Space Station (ISS). The objective of the project is to determine the relative contributions of gravity-driven fluid flows to the compositional distribution, incorporation of impurities and defects, and deviation from stoichiometry observed in the crystals grown by vapor transport as results of buoyance-driven convection and growth interface fluctuations caused by irregular fluid-flows on Earth. The investigation consists of extensive ground-based experimental and theoretical research efforts and concurrent flight experimentation. The objectives of the ground-based studies are (1) obtain the experimental data and conduct the analyses required to define the optimum growth parameters for the flight experiments, (2) perfect various characterization techniques to establish the standard procedure for material characterization, (3) quantitatively establish the characteristics of the crystals grown on Earth as a basis for subsequent comparative evaluations of the crystals grown in a low-gravity environment and (4) develop theoretical and analytical methods required for such evaluations. ZnSe and related ternary compounds have been grown by vapor transport technique with real time in-situ non-invasive monitoring techniques. The grown crystals have been characterized extensively by various techniques to correlate the grown crystal properties with the growth conditions.
Smectites on Cape York, Matijevic Hill, Mars, Observed and Characterized by Crism and Opportunity
NASA Technical Reports Server (NTRS)
Arvidson, R.; Bennett, K.; Catalano, J.; Fraeman, A.; Gellert, R.; Guinness, E.; Morris, R.; Murchie, S.; Smith, M.; Squyres, S.;
2013-01-01
Opportunity has conducted an extensive "walk-about" and set of in-situ measurements on strata exposed on the inboard side of Cape York, a segment of the dissected rim of the Noachian-age approx.22 km wide Endeavour crater [1] (Fig. 1). The specific region for the observations (Matijevic Hill) was chosen based on along track oversampled (ATO) CRISM hyperspectral observations (processed to 5 m/pixel) that showed the presence of exposures of Fe/Mg smectite phyllosilicates. We describe the first ground-based observations of phyllosilicates on Mars and discuss implications based on the combined CRISM and Opportunity measurements.
REMEDIAL COSTS FOR MTBE IN SOIL AND GROUND WATER
The extensive contamination of methyl tertiary butyl ether (MTBE) in ground water has introduced concerns about the increased cost of remediation of MTBE releases compared to sites with BTEX only contamination. In an attempt to evaluate these costs, cost information for 311 site...
REMEDIAL COSTS FOR MTBE IN SOIL AND GROUND WATER
The extensive contamination of methyl tertiary butyl ether (MTBE) in ground water has introduced concerns about the increased cost of remediation of MTBE releases compared to sites with BTEX only contamination. In an attempt to evaluate these costs, cost information for 311 sit...
NASA Technical Reports Server (NTRS)
Gudimenko, Y.; Ng, R.; Iskanderova, Z.; Kleiman, J.; Grigorevsky, A.; Kiseleva, L.; Finckenor, M.; Edwards, D.
2005-01-01
Research has been continued to further improve the space durability of conductive and non-conductive polymer-based paints and of conductive thermal control paints for space applications. Efforts have been made to enhance the space durability and stability of functional Characteristics in ground-based space environment imitating conditions, using specially developed surface modification treatment. The results of surface modification of new conductive paints, including the ground-based testing in aggressive oxidative environments, such as atomic oxygen/UV and oxygen plasma, and performance evaluation are presented. Functional properties and performance characteristics, such as thermal optical properties (differential solar absorptance and thermal emittance representing the thermal optical performance of thermal control paints) and surface resistivity characteristics of pristine, surface modified, and tested materials were verified. Extensive surface analysis studies have been performed using complementary surface analyses including SEM/EDS and XPS. Test results revealed that the successfully treated materials exhibit reduced mass loss and no surface morphology change, thus indicating good protection from the severe oxidative environment. It was demonstrated that the developed surface modification treatment could be applied successfully to charge dissipative and conductive paints.
77 FR 62267 - Proposed Extension of Existing Information Collection; Gamma Radiation Surveys
Federal Register 2010, 2011, 2012, 2013, 2014
2012-10-12
... Extension of Existing Information Collection; Gamma Radiation Surveys AGENCY: Mine Safety and Health...-9440 (voice); or 202-693-9441 (facsimile). SUPPLEMENTARY INFORMATION: I. Background Gamma radiation... debilitating occupational diseases. Natural sources include rocks, soils, and ground water. Gamma radiation...
Giles, Tracey M; de Lacey, Sheryl; Muir-Cochrane, Eimear
2016-01-01
Grounded theory method has been described extensively in the literature. Yet, the varying processes portrayed can be confusing for novice grounded theorists. This article provides a worked example of the data analysis phase of a constructivist grounded theory study that examined family presence during resuscitation in acute health care settings. Core grounded theory methods are exemplified, including initial and focused coding, constant comparative analysis, memo writing, theoretical sampling, and theoretical saturation. The article traces the construction of the core category "Conditional Permission" from initial and focused codes, subcategories, and properties, through to its position in the final substantive grounded theory.
NASA Astrophysics Data System (ADS)
Barfod, Adrian A. S.; Møller, Ingelise; Christiansen, Anders V.
2016-11-01
We present a large-scale study of the petrophysical relationship of resistivities obtained from densely sampled ground-based and airborne transient electromagnetic surveys and lithological information from boreholes. The overriding aim of this study is to develop a framework for examining the resistivity-lithology relationship in a statistical manner and apply this framework to gain a better description of the large-scale resistivity structures of the subsurface. In Denmark very large and extensive datasets are available through the national geophysical and borehole databases, GERDA and JUPITER respectively. In a 10 by 10 km grid, these data are compiled into histograms of resistivity versus lithology. To do this, the geophysical data are interpolated to the position of the boreholes, which allows for a lithological categorization of the interpolated resistivity values, yielding different histograms for a set of desired lithological categories. By applying the proposed algorithm to all available boreholes and airborne and ground-based transient electromagnetic data we build nation-wide maps of the resistivity-lithology relationships in Denmark. The presented Resistivity Atlas reveals varying patterns in the large-scale resistivity-lithology relations, reflecting geological details such as available source material for tills. The resistivity maps also reveal a clear ambiguity in the resistivity values for different lithologies. The Resistivity Atlas is highly useful when geophysical data are to be used for geological or hydrological modeling.
Spaceborne SAR Data for Aboveground-Biomass Retrieval of Indian Tropical Forests
NASA Astrophysics Data System (ADS)
Khati, U.; Singh, G.; Musthafa, M.
2017-12-01
Forests are important and indispensable part of the terrestrial ecosystems, and have a direct impact on the global carbon cycle. Forest biophysical parameters such as forest stand height and forest above-ground biomass (AGB) are forest health indicators. Measuring the forest biomass using traditional ground survey techniques are man-power consuming and have very low spatial coverage. Satellite based remote sensing techniques provide synoptic view of the earth with continuous measurements over large, inaccessible forest regions. Satellite Synthetic Aperture Radar (SAR) data has been shown to be sensitive to these forest bio-physical parameters and have been extensively utilized over boreal and tropical forests. However, there are limited studies over Indian tropical forests due to lack of auxiliary airborne data and difficulties in manual in situ data collection. In this research work we utilize spaceborne data from TerraSAR-X/TanDEM-X and ALOS-2/PALSAR-2 and implement both Polarimetric SAR and PolInSAR techniques for retrieval of AGB of a managed tropical forest in India. The TerraSAR-X/TanDEM-X provide a single-baseline PolInSAR data robust to temporal decorrelation. This would be used to accurately estimate the forest stand height. The retrieved height would be an input parameter for modelling AGB using the L-band ALOS-2/PALSAR-2 data. The IWCM model is extensively utilized to estimate AGB from SAR observations. In this research we utilize the six component scattering power decomposition (6SD) parameters and modify the IWCM based technique for a better retrieval of forest AGB. PolInSAR data shows a high estimation accuracy with r2 of 0.8 and a RMSE of 2 m. With this accurate height provided as input to the modified model along with 6SD parameters shows promising results. The results are validated with extensive field based measurements, and are further analysed in detail.
NASA Technical Reports Server (NTRS)
Griner, Jim; Kerczewski, Bob
2017-01-01
In order to provide for the safe integration of unmanned aircraft systems (UAS) into the National Airspace System, the command and control communications link connecting the ground-based pilot with the unmanned aircraft must be highly reliable and robust, with national and international standards to enable interoperability and certification. Both line-of-sight (LOS) links using terrestrial-based communications and beyond-line-of-sight (BLOS) links using satellite communications, supported by national and international standards, are required for integrated UAS operations. The National Aeronautics and Space Administration (NASA) has undertaken an extensive technology development and test program in order to provide the required technical data needed to enable C2 standards development. NASAs UAS Integration in the National Airspace System (NAS), or UAS in the NAS Project, included as a major element the Command and Control Communications (C2) Subproject, based at NASAs Glenn Research Center. The successful first phase of the C2 Subproject, completed during 2012-2016, focused primarily on line-of-sight communications. Accomplishments included air-ground channel propagation characterization and modeling; CNPC prototype radio development; CNPC radio flight testing; satellite communications spectrum study and interference analysis; and development of C2 LOS communications standards development. The second phase of the C2 Subproject will focus primarily on beyond-line-of-sight communications, although a follow-on activity for terrestrial LOS communications, known as Terrestrial Extension, is also included. In addition to the terrestrial element, Phase 2 also includes technology development and testing activities for Ka-Band BLOS C2 Satellite Communications; Ku-Band BLOS C2 Satellite Communications; Ku-Band Interference and Propagation; and C-Band Satellite Communications. This paper will provide brief overviews of the C2 Subproject and its Phase I accomplishments, followed by a description of the plans for the C2 Subproject Phase 2.
NASA Technical Reports Server (NTRS)
Griner, James H.; Kerczewski, Robert J.
2017-01-01
In order to provide for the safe integration of unmanned aircraft systems (UAS) into the National Airspace System, the command and control communications link connecting the ground-based pilot with the unmanned aircraft must be highly reliable and robust, with national and international standards to enable interoperability and certification. Both line-of-sight (LOS) links using terrestrial-based communications and beyond-line-of-sight (BLOS) links using satellite communications, supported by national and international standards, are required for integrated UAS operations. The National Aeronautics and Space Administration (NASA) has undertaken an extensive technology development and test program in order to provide the required technical data needed to enable C2 standards development. NASAs UAS Integration in the National Airspace System (NAS), or UAS in the NAS Project, included as a major element the Command and Control Communications (C2) Subproject, based at NASAs Glenn Research Center. The successful first phase of the C2 Subproject, completed during 2012-2016, focused primarily on line-of-sight communications. Accomplishments included air-ground channel propagation characterization and modeling; CNPC prototype radio development; CNPC radio flight testing; satellite communications spectrum study and interference analysis; and development of C2 LOS communications standards development. The second phase of the C2 Subproject will focus primarily on beyond-line-of-sight communications, although a follow-on activity for terrestrial LOS communications, known as Terrestrial Extension, is also included. In addition to the terrestrial element, Phase 2 also includes technology development and testing activities for Ka-Band BLOS C2 Satellite Communications; Ku-Band BLOS C2 Satellite Communications; Ku-Band Interference and Propagation; and C-Band Satellite Communications. This paper will provide brief overviews of the C2 Subproject and its Phase I accomplishments, followed by a description of the plans for the C2 Subproject Phase 2.
Theory and experiments in model-based space system anomaly management
NASA Astrophysics Data System (ADS)
Kitts, Christopher Adam
This research program consists of an experimental study of model-based reasoning methods for detecting, diagnosing and resolving anomalies that occur when operating a comprehensive space system. Using a first principles approach, several extensions were made to the existing field of model-based fault detection and diagnosis in order to develop a general theory of model-based anomaly management. Based on this theory, a suite of algorithms were developed and computationally implemented in order to detect, diagnose and identify resolutions for anomalous conditions occurring within an engineering system. The theory and software suite were experimentally verified and validated in the context of a simple but comprehensive, student-developed, end-to-end space system, which was developed specifically to support such demonstrations. This space system consisted of the Sapphire microsatellite which was launched in 2001, several geographically distributed and Internet-enabled communication ground stations, and a centralized mission control complex located in the Space Technology Center in the NASA Ames Research Park. Results of both ground-based and on-board experiments demonstrate the speed, accuracy, and value of the algorithms compared to human operators, and they highlight future improvements required to mature this technology.
Director, Operational Test and Evaluation FY 2005 Annual Report
2005-12-01
agent at room temperature, and moderate humidity in a specially-sealed chamber at Dugway Proving Ground , Utah. • The tolerance of the...Manned Ground Vehicles. The Army is conducting extensive NLOS-C developmental test firings at Yuma Proving Ground , Arizona. A detailed report on... agent , another would destroy ton containers of mustard blister agent ). After completion of a campaign, the facility will revert to OT status for
[School-Based UV-B Monitoring Project in Support of EOS-CHEM
NASA Technical Reports Server (NTRS)
Brooks, David R.
2005-01-01
This grant is an extension of Grant NAG5-8929 (Drexel Project Number 230026), resulting from extensions necessary to meet changing science objectives as described in the final report for NAG5-8929, a copy of which is attached. The instrument configuration resulting from NAG54929 has remained basically intact. Cosine response measurements conducted by James Slusser s group at Fort Collins, Colorado, in support of the proposal for Aura ground validation mentioned in the final report for NAG5-8929, indicated that there was significant light leakage to the detector through the sides of the nylon housing. This was easily remedied by machining a removable opaque collar (made from the dark same grey rigid plastic plumbing tubing as the collimating tube) that fits around the detector collar. Also during this grant period, data logging procedures were established for the UV-A instrument, to record irradiance before, during, and after an Aura overflight. This is required in order to compare spatial and temporal variability as required for ground validation of data products derived from the Ozone Monitoring Instrument (OMI). Standalone 12-bit loggers from Onset Computer Corporation (the U12 series), which were not available at the start of these projects, makes possible relatively inexpensive logging for these instruments at a usable resolution. configuration and disposition of these instruments, including the final version of a GLOBE protocol for using the instruments, currently depend on action taken on the Aura ground validation proposal submitted in 2004. A copy of that proposal is attached.
Coordinated Ground- and Space-based Multispectral Campaign to Study Equatorial Spread-F Formation
NASA Astrophysics Data System (ADS)
Finn, S. C.; Geddes, G.; Aryal, S.; Stephan, A. W.; Budzien, S. A.; Duggirala, P. R.; Chakrabarti, S.; Valladares, C.
2016-12-01
We present a concept for a multispectral campaign using coordinated data from state-of-the-art instruments aboard the International Space Station (ISS) and multiple ground-based spectrometers and digisondes deployed at low-latitudes to study the formation and development of Equatorial Spread-F (ESF). This extended observational campaign utilizes ultraviolet, visible, and radio measurements to develop a predictive capability for ESF and to study the coupling of the ionosphere-thermosphere (I-T) system during geomagnetically quiet and disturbed times. The ground-based instruments will be deployed in carefully chosen locations in the American and Indian sectors while the space-based data will provide global coverage spanning all local times and longitudes within ±51° geographic latitudes. The campaign, over an extended period covering a range of geophysical conditions, will provide the extensive data base necessary to address the important science questions. The space-based instrument suite consists of the Limb-imaging Ionospheric and Thermospheric Extreme-ultraviolet Spectrograph (LITES) and the GPS Radio Occultation and Ultraviolet Photometry-Colocated (GROUP-C) instruments, scheduled to launch to the ISS in November 2016. LITES is a compact imaging spectrograph for remote sensing of the upper atmosphere and ionosphere from 60 to 140nm and GROUP-C has a nadir-viewing FUV photometer. The ground-based instruments to be deployed for this campaign are three high-resolution imaging spectrographs capable of continuous round-the-clock airglow observations: Multiwavelength Imaging Spectrograph using Echelle grating (MISE) in India and two High Throughput and Multi-slit Imaging Spectrographs (HiT&MIS) to be deployed in Colombia and Argentina, the Low-Latitude Ionosphere Sensor Network (LISN), and the Global Ionospheric Radio Observatory (GIRO) digisondes network. We present data from the ground-based instruments, initial results from the LITES and GROUP-C instruments on-orbit, and modeling and analysis methods for the campaign. This work was supported by NSF 1315354 and 1145166, and ONR N00014-13-1-0266 grants. LITES and GROUP-C are part of the STP-H5 Payload, integrated and flown under the direction of the DoD Space Test Program.
High Accuracy Monocular SFM and Scale Correction for Autonomous Driving.
Song, Shiyu; Chandraker, Manmohan; Guest, Clark C
2016-04-01
We present a real-time monocular visual odometry system that achieves high accuracy in real-world autonomous driving applications. First, we demonstrate robust monocular SFM that exploits multithreading to handle driving scenes with large motions and rapidly changing imagery. To correct for scale drift, we use known height of the camera from the ground plane. Our second contribution is a novel data-driven mechanism for cue combination that allows highly accurate ground plane estimation by adapting observation covariances of multiple cues, such as sparse feature matching and dense inter-frame stereo, based on their relative confidences inferred from visual data on a per-frame basis. Finally, we demonstrate extensive benchmark performance and comparisons on the challenging KITTI dataset, achieving accuracy comparable to stereo and exceeding prior monocular systems. Our SFM system is optimized to output pose within 50 ms in the worst case, while average case operation is over 30 fps. Our framework also significantly boosts the accuracy of applications like object localization that rely on the ground plane.
CCSDS Spacecraft Monitor and Control Service Framework
NASA Technical Reports Server (NTRS)
Merri, Mario; Schmidt, Michael; Ercolani, Alessandro; Dankiewicz, Ivan; Cooper, Sam; Thompson, Roger; Symonds, Martin; Oyake, Amalaye; Vaughs, Ashton; Shames, Peter
2004-01-01
This CCSDS paper presents a reference architecture and service framework for spacecraft monitoring and control. It has been prepared by the Spacecraft Monitoring and Control working group of the CCSDS Mission Operations and Information Management Systems (MOIMS) area. In this context, Spacecraft Monitoring and Control (SM&C) refers to end-to-end services between on- board or remote applications and ground-based functions responsible for mission operations. The scope of SM&C includes: 1) Operational Concept: definition of an operational concept that covers a set of standard operations activities related to the monitoring and control of both ground and space segments. 2) Core Set of Services: definition of an extensible set of services to support the operational concept together with its information model and behaviours. This includes (non exhaustively) ground systems such as Automatic Command and Control, Data Archiving and Retrieval, Flight Dynamics, Mission Planning and Performance Evaluation. 3) Application-layer information: definition of the standard information set to be exchanged for SM&C purposes.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Frolov, T.; Setyawan, W.; Kurtz, R. J.
We report a computational discovery of novel grain boundary structures and multiple grain boundary phases in elemental bcc tungsten. While grain boundary structures created by the - surface method as a union of two perfect half crystals have been studied extensively, it is known that the method has limitations and does not always predict the correct ground states. Here, we use a newly developed computational tool, based on evolutionary algorithms, to perform a grand-canonical search of high-angle symmetric tilt boundary in tungsten, and we find new ground states and multiple phases that cannot be described using the conventional structural unitmore » model. We use MD simulations to demonstrate that the new structures can coexist at finite temperature in a closed system, confirming these are examples of different GB phases. The new ground state is confirmed by first-principles calculations.Evolutionary grand-canonical search predicts novel grain boundary structures and multiple grain boundary phases in elemental body-centered cubic (bcc) metals represented by tungsten, tantalum and molybdenum.« less
Contador, Israel; Fernández-Calvo, Bernardino; Palenzuela, David L; Campos, Francisco Ramos; Rivera-Navarro, Jesús; de Lucena, Virginia Menezes
2015-11-01
We examined whether grounded optimism and external locus of control are associated with admission to dementia day care centers (DCCs). A total of 130 informal caregivers were recruited from the Alzheimer's Association in Salamanca (northwest Spain). All caregivers completed an assessment protocol that included the Battery of Generalized Expectancies of Control Scales (BEEGC-20, acronym in Spanish) as well as depression and burden measures. The decision of the care setting at baseline assessment (own home vs DCC) was considered the main outcome measure in the logistic regression analyses. Grounded optimism was a preventive factor for admission (odds ratio [OR]: 0.34 and confidence interval [CI]: 0.15-0.75), whereas external locus of control (OR: 2.75, CI: 1.25-6.03) increased the probabilities of using DCCs. Depression mediated the relationship between optimism and DCCs, but this effect was not consistent for burden. Grounded optimism promotes the extension of care at home for patients with dementia. © The Author(s) 2013.
Yamada, Takayoshi; Demura, Shin-ichi
2009-01-01
This study aimed to examine the relationships between ground reaction force during a sit-to-stand (STS) movement and physical activity and falling risk of the elderly and the difference of the movement characteristics between the young and the elderly. Sixty elderly females who can achieve a STS movement by themselves and 30 healthy young females were measured for ground reaction force during STS movement from a chair, adjusted for lower leg length height. The elderly's physical activity and falling risk were also assessed. Physical activity and falling risk significantly correlated with parameters on force exertion during hip lift-off and knee-hip joint extension phases (|r|=0.26-0.41). Significant differences were found in ground reaction force parameters of all phases between the young and the elderly and STS movement of the elderly was suggested to result in poor force exertion and slowing down. The above tendency was noticeable in the hip lift-off and knee-hip joint extension phases. In conclusion, force exertion in hip lift-off and knee-hip joint extension phases of STS movement is related to physical activity and falling risk in the elderly. These phases may be useful to evaluate the elderly's physical activity and falling risk.
Hong, Yoon No Gregory; Shin, Choongsoo S
2015-12-01
Falls on stairs often result in severe injury and occur twice as frequently in women. However, gender differences in kinetics and kinematics during stair descent are unknown. Thus, this study aimed to determine whether gender differences of knee and ankle biomechanics exist in the sagittal plane during the stair-to-ground descending transition. It was hypothesized that 1) women would reveal higher ground-toe-trochanter angle and lower ground-toe length during stair-to-ground descent transition than men; and 2) women would reveal lower peak knee extension moment during stair-to-ground descent transition than men. Fifteen men and fifteen women were recruited and performed a stair descent activity. Kinetic and kinematic data were obtained using a force plate and motion capture system. The women performed the stair descent with a lower peak knee extension moment and a peak knee power at the early weight acceptance phase. The women also revealed a higher ground-toe-trochanter angle and a lower ground-toe length, which indicated a more forward position of the lower extremity relative to the toe contact point at both the initial contact and at the time of peak kinematic and kinetic events. This study found that knee and ankle kinematics and kinetics differed significantly between the genders due to differences in ground-toe-trochanter angle. Women have a different stair descending strategy that reduces the demand of the lower extremity muscle function, but this strategy seems to increase the risk of falls. Copyright © 2015 Elsevier Ltd. All rights reserved.
Fuel models and fire potential from satellite and surface observations
Burgan, R.E.; Klaver, R.W.; Klarer, J.M.
1998-01-01
A national 1-km resolution fire danger fuel model map was derived through use of previously mapped land cover classes and ecoregions, and extensive ground sample data, then refined through review by fire managers familiar with various portions of the U.S. The fuel model map will be used in the next generation fire danger rating system for the U.S., but it also made possible immediate development of a satellite and ground based fire potential index map. The inputs and algorithm of the fire potential index are presented, along with a case study of the correlation between the fire potential index and fire occurrence in California and Nevada. Application of the fire potential index in the Mediterranean ecosystems of Spain, Chile, and Mexico will be tested.
Republic P-47G Thunderbolt Undergoes Ground Testing
1945-06-21
A Republic P-47G Thunderbolt is tested with a large blower on the hangar apron at the National Advisory Committee for Aeronautics (NACA) Aircraft Engine Research Laboratory in Cleveland, Ohio. The blower could produce air velocities up to 250 miles per hour. This was strong enough to simulate take-off power and eliminated the need to risk flights with untried engines. The Republic P-47G was loaned to the laboratory to test NACA modifications to the Wright R-2800 engine’s cooling system at higher altitudes. The ground-based tests, seen here, were used to map the engine’s normal operating parameters. The P-47G then underwent an extensive flight test program to study temperature distribution among the engine’s 18 cylinders and develop methods to improve that distribution.
Comparison of different pairing fluctuation approaches to BCS-BEC crossover
DOE Office of Scientific and Technical Information (OSTI.GOV)
Levin, Kathryn; Chen Qijin; Zhejiang Institute of Modern Physics and Department of Physics, Zhejiang University, Hangzhou, Zhejiang 310027
2010-02-15
The subject of BCS-Bose-Einstein condensation (BEC) crossover is particularly exciting because of its realization in ultracold atomic Fermi gases and its possible relevance to high temperature superconductors. In this paper we review the body of theoretical work on this subject, which represents a natural extension of the seminal papers by Leggett and by Nozieres and Schmitt-Rink (NSR). The former addressed only the ground state, now known as the 'BCS-Leggett' wave-function, and the key contributions of the latter pertain to calculations of the superfluid transition temperature T{sub c}. These two papers have given rise to two main and, importantly, distinct, theoreticalmore » schools in the BCS-BEC crossover literature. The first of these extends the BCS-Leggett ground state to finite temperature and the second extends the NSR scheme away from T{sub c} both in the superfluid and normal phases. It is now rather widely accepted that these extensions of NSR produce a different ground state than that first introduced by Leggett. This observation provides a central motivation for the present paper which seeks to clarify the distinctions in the two approaches. Our analysis shows how the NSR-based approach views the bosonic contributions more completely but treats the fermions as 'quasi-free'. By contrast, the BCS-Leggett based approach treats the fermionic contributions more completely but treats the bosons as 'quasi-free'. In a related fashion, the NSR-based schemes approach the crossover between BCS and BEC by starting from the BEC limit and the BCS-Leggett based scheme approaches this crossover by starting from the BCS limit. Ultimately, one would like to combine these two schemes. There are, however, many difficult problems to surmount in any attempt to bridge the gap in the two theory classes. In this paper we review the strengths and weaknesses of both approaches. The flexibility of the BCS-Leggett based approach and its ease of handling make it widely used in T=0 applications, although the NSR-based schemes tend to be widely used at T{ne}0. To reach a full understanding, it is important in the future to invest effort in investigating in more detail the T=0 aspects of NSR-based theory and at the same time the T{ne}0 aspects of BCS-Leggett theory.« less
Hydrologic considerations in defining isolated wetlands
Winter, T.C.; LaBaugh, J.W.
2003-01-01
Wetlands that are not connected by streams to other surface-water bodies are considered to be isolated. Although the definition is based on surface-water connections to other water bodies, isolated wetlands commonly are integral parts of extensive ground-water flow systems, and isolated wetlands can spill over their surface divides into adjacent surface-water bodies during periods of abundant precipitation and high water levels. Thus, characteristics of ground-water flow and atmospheric-water flow affect the isolation of wetlands. In general, the degree that isolated wetlands are connected through the ground-water system to other surface-water bodies depends to a large extent on the rate that ground water moves and the rate that hydrologic stresses can be transmitted through the ground-water system. Water that seeps from an isolated wetland into a gravel aquifer can travel many kilometers through the ground-water system in one year. In contrast, water that seeps from an isolated wetland into a clayey or silty substrate may travel less than one meter in one year. For wetlands that can spill over their surface watersheds during periods of wet climate conditions, their isolation is related to the height to a spill elevation above normal wetland water level and the recurrence interval of various magnitudes of precipitation. The concepts presented in this paper indicate that the entire hydrologic system needs to be considered in establishing a definition of hydrologic isolation.
Dichlorobenzene in ground water: Evidence for long-term persistence
Barber, L.B.
1988-01-01
Hydrologic and geochemical evidence were used to establish the long-term persistence of dichlorobenzene in ground water that has been contaminated from 50 years of rapid-infiltration sewage disposal. An extensive plume of dichlorobenzene extends more than 3,500 meters downgradient from the disposal beds, with concentrations of the combined isomers ranging from less than 0.01 to over 1.0 ??g/l. Based on estimates of maximum ground-water flow velocities, a minimum age of 20 years was established for the farthest downgradient zone of dichlorobenzene contamination. Branched-chained, alkylbenzenesulfonic acid surfactants, that were introduced into the ground water prior to 1966, occur along with dichlorobenzene in the downgradient part of the plume, further establish residence of the compounds in the aquifer for at least 20 years. Although dichlorobenzene can be biologically degraded under aerobic conditions, its persistence at this field site is attributed to the dynamics of the ground-water system. Denitrifying conditions, resulting from the degradation of organic compounds in the aquifer near the disposal beds, appear to have enhanced the persistence of dichlorobenzene, which is not degraded by anaerobic bacteria. Biological degradation of dichlorobenzene in the aerobic part of the plume downgradient from the source is probably limited by the paucity of a suitable organic-carbon substrate and the low concentrations of dissolved oxygen in the contaminated ground water.
Diseases of Ornamental and Shade Trees, Shrubs, Vines, and Ground Covers.
ERIC Educational Resources Information Center
Nichols, Lester P.
This agriculture extension service publication from Pennsylvania State University covers the identification and control of common ornamental trees, shrubs, and ground cover diseases. The publication is divided into sections. The first section discusses the diseases of ornamental and shade trees, including general diseases and diseases of specific…
Satisfaction with College Major: A Grounded Theory Study
ERIC Educational Resources Information Center
Milsom, Amy; Coughlin, Julie
2015-01-01
All college students must eventually choose and complete a major. Many switch majors, and some change it multiple times. Despite extensive literature addressing factors that influence students' initial choice of major, few scholars have examined students' experiences after enrollment in a selected major. In this study, we used a grounded theory…
Adjusting Conceptual Pacts in Three-Party Conversation
ERIC Educational Resources Information Center
Yoon, Si On; Brown-Schmidt, Sarah
2014-01-01
During conversation, partners develop representations of jointly known information--the common ground--and use this knowledge to guide subsequent linguistic exchanges. Extensive research on 2-party conversation has offered key insights into this process, in particular, its partner-specificity: Common ground that is shared with 1 partner is not…
Discovering the invisible universe
NASA Astrophysics Data System (ADS)
Friedman, Herbert
1991-02-01
The history of astronomical observations outside the visible range is surveyed in a review for general readers. Consideration is given to Jansky's discovery of cosmic radio emission, the pioneering radio observers of the 1940s, the larger radio telescopes built since 1950, aperture synthesis and the Very Large Array, terrestrial and space VLBI networks, ground-based and satellite observations in the IR band, the discovery and early laboratory characterization of X-rays, and X-ray observations from sounding rockets and satellites. Extensive photographs, drawings, diagrams, and sample images are provided.
Deep space network resource scheduling approach and application
NASA Technical Reports Server (NTRS)
Eggemeyer, William C.; Bowling, Alan
1987-01-01
Deep Space Network (DSN) resource scheduling is the process of distributing ground-based facilities to track multiple spacecraft. The Jet Propulsion Laboratory has carried out extensive research to find ways of automating this process in an effort to reduce time and manpower costs. This paper presents a resource-scheduling system entitled PLAN-IT with a description of its design philosophy. The PLAN-IT's current on-line usage and limitations in scheduling the resources of the DSN are discussed, along with potential enhancements for DSN application.
Facilitating the exploitation of ERTS imagery using snow enhancement techniques
NASA Technical Reports Server (NTRS)
Wobber, F. J. (Principal Investigator); Martin, K. R.; Sheffield, C.; Russell, O.; Amato, R. V.
1973-01-01
The author has identified the following significant results. EarthSat has established an effective mail-based method for obtaining timely ground truth (snow depth) information over an extensive area. The method is both efficient and inexpensive compared with the cost of a similarly scaled direct field checking effort. Additional geological information has been acquired which is not shown in geological maps in the area. Excellent quality snow-free ERTS-1 transparencies of the test areas have been received and are being analyzed.
Space Weather: Historical and Contemporary Perspectives
NASA Astrophysics Data System (ADS)
Lanzerotti, Louis J.
2017-11-01
A somewhat personalized overview is presented of the effects of solar-terrestrial processes on electrical technologies, beginning with the electrical telegraphs in the mid-eighteenth century to the current era of extensive ground- and space-based commercial and governmental technical systems (including national security) upon which modern society depends. As human technologies increased in diversity over the last century and a half, space weather effects have continued to be of significant importance in the successful design and operations of many of these technologies.
Radio Frequency Identification for Space Habitat Inventory and Stowage Allocation Management
NASA Technical Reports Server (NTRS)
Wagner, Carole Y.
2015-01-01
To date, the most extensive space-based inventory management operation has been the International Space Station (ISS). Approximately 20,000 items are tracked with the Inventory Management System (IMS) software application that requires both flight and ground crews to update the database daily. This audit process is manually intensive and laborious, requiring the crew to open cargo transfer bags (CTBs), then Ziplock bags therein, to retrieve individual items. This inventory process contributes greatly to the time allocated for general crew tasks.
The polarimeter and the multispectral radiometer as remote probes of aerosols
NASA Technical Reports Server (NTRS)
Kuriyan, J. G.
1975-01-01
Attempts made to establish the viability of the polarimeter as a ground based remote probe of atmospheric aerosols under varying meteorological conditions are reported. Extension radiometer data are also given and a comparison was made with polarimeter data to determine if one could complement/supplement the other. The analyses show that the two instruments are complementary devices and any information obtained from one will greatly facilitate the analysis of the other. Detailed results are given in graphical form.
Feed forward and feedback control for over-ground locomotion in anaesthetized cats
NASA Astrophysics Data System (ADS)
Mazurek, K. A.; Holinski, B. J.; Everaert, D. G.; Stein, R. B.; Etienne-Cummings, R.; Mushahwar, V. K.
2012-04-01
The biological central pattern generator (CPG) integrates open and closed loop control to produce over-ground walking. The goal of this study was to develop a physiologically based algorithm capable of mimicking the biological system to control multiple joints in the lower extremities for producing over-ground walking. The algorithm used state-based models of the step cycle each of which produced different stimulation patterns. Two configurations were implemented to restore over-ground walking in five adult anaesthetized cats using intramuscular stimulation (IMS) of the main hip, knee and ankle flexor and extensor muscles in the hind limbs. An open loop controller relied only on intrinsic timing while a hybrid-CPG controller added sensory feedback from force plates (representing limb loading), and accelerometers and gyroscopes (representing limb position). Stimulation applied to hind limb muscles caused extension or flexion in the hips, knees and ankles. A total of 113 walking trials were obtained across all experiments. Of these, 74 were successful in which the cats traversed 75% of the 3.5 m over-ground walkway. In these trials, the average peak step length decreased from 24.9 ± 8.4 to 21.8 ± 7.5 (normalized units) and the median number of steps per trial increased from 7 (Q1 = 6, Q3 = 9) to 9 (8, 11) with the hybrid-CPG controller. Moreover, within these trials, the hybrid-CPG controller produced more successful steps (step length ≤ 20 cm ground reaction force ≥ 12.5% body weight) than the open loop controller: 372 of 544 steps (68%) versus 65 of 134 steps (49%), respectively. This supports our previous preliminary findings, and affirms that physiologically based hybrid-CPG approaches produce more successful stepping than open loop controllers. The algorithm provides the foundation for a neural prosthetic controller and a framework to implement more detailed control of locomotion in the future.
Feed forward and feedback control for over-ground locomotion in anaesthetized cats
Mazurek, K A; Holinski, B J; Everaert, D G; Stein, R B; Etienne-Cummings, R; Mushahwar, V K
2012-01-01
The biological central pattern generator (CPG) integrates open and closed loop control to produce over-ground walking. The goal of this study was to develop a physiologically based algorithm capable of mimicking the biological system to control multiple joints in the lower extremities for producing over-ground walking. The algorithm used state-based models of the step cycle each of which produced different stimulation patterns. Two configurations were implemented to restore over-ground walking in five adult anaesthetized cats using intramuscular stimulation (IMS) of the main hip, knee and ankle flexor and extensor muscles in the hind limbs. An open loop controller relied only on intrinsic timing while a hybrid-CPG controller added sensory feedback from force plates (representing limb loading), and accelerometers and gyroscopes (representing limb position). Stimulation applied to hind limb muscles caused extension or flexion in the hips, knees and ankles. A total of 113 walking trials were obtained across all experiments. Of these, 74 were successful in which the cats traversed 75% of the 3.5 m over-ground walkway. In these trials, the average peak step length decreased from 24.9 ± 8.4 to 21.8 ± 7.5 (normalized units) and the median number of steps per trial increased from 7 (Q1=6, Q3 = 9) to 9 (8, 11) with the hybrid-CPG controller. Moreover, these trials, the hybrid-CPG controller produced more successful steps (step length ≤ 20 cm; ground reaction force ≥ 12.5% body weight) than the open loop controller: 372 of 544 steps (68%) versus 65 of 134 steps (49%), respectively. This supports our previous preliminary findings, and affirms that physiologically based hybrid-CPG approaches produce more successful stepping than open loop controllers. The algorithm provides the foundation for a neural prosthetic controller and a framework to implement more detailed control of locomotion in the future. PMID:22328615
Lights Out Operations of a Space, Ground, Sensorweb
NASA Technical Reports Server (NTRS)
Chien, Steve; Tran, Daniel; Johnston, Mark; Davies, Ashley Gerard; Castano, Rebecca; Rabideau, Gregg; Cichy, Benjamin; Doubleday, Joshua; Pieri, David; Scharenbroich, Lucas;
2008-01-01
We have been operating an autonomous, integrated sensorweb linking numerous space and ground sensors in 24/7 operations since 2004. This sensorweb includes elements of space data acquisition (MODIS, GOES, and EO-1), space asset retasking (EO-1), integration of data acquired from ground sensor networks with on-demand ground processing of data into science products. These assets are being integrated using web service standards from the Open Geospatial Consortium. Future plans include extension to fixed and mobile surface and subsurface sea assets as part of the NSF's ORION Program.
Monitoring of the Ground Fissure Activity Within Yuncheng Basin by Time Series Insar
NASA Astrophysics Data System (ADS)
Zhang, F.; Yang, C. S.; Zhao, C. Y.; Liu, R. C.
2018-04-01
Yuncheng area is one of the most extensive distributions of ground fissures in Shanxi basin, especially in Yanhu District of Yuncheng, the disaster of ground fissures and ground subsidence are the most serious. According to previous studies, the development and distribution of the ground fissures in this area are mainly controlled by the underlying active faults. In order to provide a better understanding of the formation mechanism, the deformation of ground fissures and its surrounding environment should be taken into consideration. In this paper, PS-InSAR technology was employed to assess the time-series ground deformation of Yuncheng ground fissures and its surrounding area with X-band TerraSAR images from 2013 to 2015. The interaction between ground fissures activity and land subsidence, groundwater, precipitation and surrounding faults will be discussed.
NASA Technical Reports Server (NTRS)
1979-01-01
A plan for the production of two PEP flight systems is defined. The task's milestones are described. Provisions for the development and assembly of new ground support equipment required for both testing and launch operations are included.
What Influences Agents to Pursue a Career in Extension?
ERIC Educational Resources Information Center
Arnold, Shannon; Place, Nick
2010-01-01
The qualitative study reported here explored why agricultural agents pursue an Extension career. A purposive sample was used to select twelve Florida agricultural agents. Interviews investigated positive and negative influences that affected agents' employment decisions. Grounded theory was used as the primary data analysis method (Strauss &…
Simulation of the effects of development of the ground-water flow system of Long Island, New York
Buxton, Herbert T.; Smolensky, Douglas A.
1999-01-01
Extensive development on Long Island since the late 19th century and projections of increased urbanization and ground-water use makes effective water-resource management essential for preservation of the island's hydrologic environment and maintenance of a reliable source of water supply. This report presents results of a ground-water flow simulation analysis of the effects of development on the Long Island ground-water system. It describes ground-water levels, stream-flow, and the ground-water budget for the predevelopment period (pre-1900), the 1960's drought, and a more recent (1968-83) period with significant hydrologic stress. The report also presents estimated effects of a proposed water-supply strategy for the year 2020. Long Island has three major aquifers-the upper glacial (water-table), the Magothy, and the Lloyd aquifers-that are separated to varying degrees by confining units. Before development, recharge from precipitation entered the ground-water system at a rate of more than 1.1 billion gallons per day. An equal amount discharged to streams (41 percent), the shore (52 percent), and subsea boundaries (7 percent) . Urbanization and withdrawal of more than 400 Mgal/d (million gallons per day) from wells have resulted in local effects that include declines in ground-water levels, drying up and burial of streams and wetlands, reduction of ground-water recharge by increased overland flow to the ocean, a general decrease in ground-water discharge, and salt water intrusion. In some areas, the reduction in recharge is mitigated by leakage from water-supply and wastewater disposal lines, and infiltration of storm water through recharge basins. During 1968-83, a net loss of 240 Mgal/d from the ground-water system caused a decrease in ground-water discharge to streams (135 Mgal/d), to the shore (82 Mgal/d), and to subsea boundaries (23Mgal/d).The greatest adverse effects have been in western Long Island, where the most severe development has occurred. This analysis shows stream base flow to be highly sensitive to water-table fluctuations, and long streams to be more sensitive than short ones. A water-supply scenario for the year 2020 was simulated that employs redistribution of pumping centers to mitigate extreme local effects . Although the net stress on the ground-water system was projected to increase 57 Mgal/d (24 percent) above that of 1968-83, redistribution of ground-water withdrawals across the island would allow recovery of cones of depression in western Long Island, thereby reducing the threat of salt water intrusion and increasing base flow of some streams . The increased stress would cause a net decrease in base flow island wide of 44 Mgal/d; total base flow would be 281 Mgal/d - 39 percent below predevelopment levels or 14 percent below 1968-83 levels. The most severe effects would be in Nassau and western Suffolk Counties.
Kanai, H
1993-07-01
A dynamic analysis was made on the knees with chronic anterior cruciate ligament (ACL) insufficiency for antero-posterior instability and abnormal rotation, also evaluating them for ground reaction force and muscle strength of knee extension. Studies were carried out on 51 patients with chronic unilateral ACL insufficiency and 80 knees of 40 healthy male and female young adults as controls. Using a knee motion analyser, an apparatus designed to analyse three dimensional knee motion, the gait was studied on a force plate. At the same time, the muscle strength of knee extension was measured with a Kinetic-Communicator (KIN-COM). In the dynamic analysis of the knee motion anterior instability was notable at a small angle of flexion. Qualitative evaluation of the knee motion revealed three patterns of rotation. The evaluation of ground reaction force showed that the rise from the heel strike was slow, its slope was gentle and the effect of weight removal was unclear. The evaluation of the muscle strength of knee extension revealed a decrease in torque of muscular contraction at 20 degrees of knee flexion.
NASA Astrophysics Data System (ADS)
Pollack, I. B.; Ryerson, T. B.; Trainer, M.; Parrish, D. D.; Andrews, A. E.; Atlas, E. L.; Blake, D. R.; Brown, S. S.; Commane, R.; Daube, B. C.; Gouw, J. A.; Dubé, W. P.; Flynn, J.; Frost, G. J.; Gilman, J. B.; Grossberg, N.; Holloway, J. S.; Kofler, J.; Kort, E. A.; Kuster, W. C.; Lang, P. M.; Lefer, B.; Lueb, R. A.; Neuman, J. A.; Nowak, J. B.; Novelli, P. C.; Peischl, J.; Perring, A. E.; Roberts, J. M.; Santoni, G.; Schwarz, J. P.; Spackman, J. R.; Wagner, N. L.; Warneke, C.; Washenfelder, R. A.; Wofsy, S. C.; Xiang, B.
2011-11-01
Airborne and ground-based measurements during the CalNex (California Research at the Nexus of Air Quality and Climate Change) field study in May/June 2010 show a weekend effect in ozone in the South Coast Air Basin (SoCAB) consistent with previous observations. The well-known and much-studied weekend ozone effect has been attributed to weekend reductions in nitrogen oxide (NOx = NO + NO2) emissions, which affect ozone levels via two processes: (1) reduced ozone loss by titration and (2) enhanced photochemical production of ozone due to an increased ratio of non-methane volatile organic compounds (VOCs) to NOx. In accord with previous assessments, the 2010 airborne and ground-based data show an average decrease in NOx of 46 ± 11% and 34 ± 4%, respectively, and an average increase in VOC/NOxratio of 48 ± 8% and 43 ± 22%, respectively, on weekends. This work extends current understanding of the weekend ozone effect in the SoCAB by identifying its major causes and quantifying their relative importance from the available CalNex data. Increased weekend production of a VOC-NOxoxidation product, peroxyacetyl nitrate, compared to a radical termination product, nitric acid, indicates a significant contribution from increased photochemical production on weekends. Weekday-to-weekend differences in the products of NOx oxidation show 45 ± 13% and 42 ± 12% more extensive photochemical processing and, when compared with odd oxygen (Ox = O3 + NO2), 51 ± 14% and 22 ± 17% greater ozone production efficiency on weekends in the airborne and ground-based data, respectively, indicating that both contribute to higher weekend ozone levels in the SoCAB.
NASA Astrophysics Data System (ADS)
Pollack, I. B.; Ryerson, T. B.; Trainer, M.; Parrish, D. D.; Andrews, A. E.; Atlas, E. L.; Blake, D. R.; Brown, S. S.; Commane, R.; Daube, B. C.; de Gouw, J. A.; Dubé, W. P.; Flynn, J.; Frost, G. J.; Gilman, J. B.; Grossberg, N.; Holloway, J. S.; Kofler, J.; Kort, E. A.; Kuster, W. C.; Lang, P. M.; Lefer, B.; Lueb, R. A.; Neuman, J. A.; Nowak, J. B.; Novelli, P. C.; Peischl, J.; Perring, A. E.; Roberts, J. M.; Santoni, G.; Schwarz, J. P.; Spackman, J. R.; Wagner, N. L.; Warneke, C.; Washenfelder, R. A.; Wofsy, S. C.; Xiang, B.
2012-02-01
Airborne and ground-based measurements during the CalNex (California Research at the Nexus of Air Quality and Climate Change) field study in May/June 2010 show a weekend effect in ozone in the South Coast Air Basin (SoCAB) consistent with previous observations. The well-known and much-studied weekend ozone effect has been attributed to weekend reductions in nitrogen oxide (NOx = NO + NO2) emissions, which affect ozone levels via two processes: (1) reduced ozone loss by titration and (2) enhanced photochemical production of ozone due to an increased ratio of non-methane volatile organic compounds (VOCs) to NOx. In accord with previous assessments, the 2010 airborne and ground-based data show an average decrease in NOx of 46 ± 11% and 34 ± 4%, respectively, and an average increase in VOC/NOx ratio of 48 ± 8% and 43 ± 22%, respectively, on weekends. This work extends current understanding of the weekend ozone effect in the SoCAB by identifying its major causes and quantifying their relative importance from the available CalNex data. Increased weekend production of a VOC-NOx oxidation product, peroxyacetyl nitrate, compared to a radical termination product, nitric acid, indicates a significant contribution from increased photochemical production on weekends. Weekday-to-weekend differences in the products of NOx oxidation show 45 ± 13% and 42 ± 12% more extensive photochemical processing and, when compared with odd oxygen (Ox = O3 + NO2), 51 ± 14% and 22 ± 17% greater ozone production efficiency on weekends in the airborne and ground-based data, respectively, indicating that both contribute to higher weekend ozone levels in the SoCAB.
The Great Observatories Origins Deep Survey (GOODS): Overview and Status
NASA Astrophysics Data System (ADS)
Hook, R. N.; GOODS Team
2002-12-01
GOODS is a very large project to gather deep imaging data and spectroscopic followup of two fields, the Hubble Deep Field North (HDF-N) and the Chandra Deep Field South (CDF-S), with both space and ground-based instruments to create an extensive multiwavelength public data set for community research on the distant Universe. GOODS includes a SIRTF Legacy Program (PI: Mark Dickinson) and a Hubble Treasury Program of ACS imaging (PI: Mauro Giavalisco). The ACS imaging was also optimized for the detection of high-z supernovae which are being followed up by a further target of opportunity Hubble GO Program (PI: Adam Riess). The bulk of the CDF-S ground-based data presently available comes from an ESO Large Programme (PI: Catherine Cesarsky) which includes both deep imaging and multi-object followup spectroscopy. This is currently complemented in the South by additional CTIO imaging. Currently available HDF-N ground-based data forming part of GOODS includes NOAO imaging. Although the SIRTF part of the survey will not begin until later in the year the ACS imaging is well advanced and there is also a huge body of complementary ground-based imaging and some follow-up spectroscopy which is already publicly available. We summarize the current status of GOODS and give an overview of the data products currently available and present the timescales for the future. Many early science results from the survey are presented in other GOODS papers at this meeting. Support for the HST GOODS program presented here and in companion abstracts was provided by NASA thorugh grant number GO-9425 from the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Incorporated, under NASA contract NAS5-26555.
NASA Astrophysics Data System (ADS)
Mura, José C.; Paradella, Waldir R.; Gama, Fabio F.; Silva, Guilherme G.
2016-10-01
PSI (Persistent Scatterer Interferometry) analysis of large area is always a challenging task regarding the removal of the atmospheric phase component. This work presents an investigation of ground deformation measurements based on a combination of DInSAR Time-Series (DTS) and PSI techniques, applied in a large area of open pit iron mines located in Carajás (Brazilian Amazon Region), aiming at detect high rates of linear and nonlinear ground deformation. These mines have presented a historical of instability and surface monitoring measurements over sectors of the mines (pit walls) have been carried out based on ground based radar and total station (prisms). By using a priori information regarding the topographic phase error and phase displacement model derived from DTS, temporal phase unwrapping in the PSI processing and the removal of the atmospheric phases can be performed more efficiently. A set of 33 TerraSAR-X-1 images, acquired during the period from March 2012 to April 2013, was used to perform this investigation. The DTS analysis was carried out on a stack of multi-look unwrapped interferogram using an extension of SVD to obtain the Least-Square solution. The height errors and deformation rates provided by the DTS approach were subtracted from the stack of interferogram to perform the PSI analysis. This procedure improved the capability of the PSI analysis to detect high rates of deformation as well as increased the numbers of point density of the final results. The proposed methodology showed good results for monitoring surface displacement in a large mining area, which is located in a rain forest environment, providing very useful information about the ground movement for planning and risks control.
NASA Astrophysics Data System (ADS)
Ge, Xuming
2017-08-01
The coarse registration of point clouds from urban building scenes has become a key topic in applications of terrestrial laser scanning technology. Sampling-based algorithms in the random sample consensus (RANSAC) model have emerged as mainstream solutions to address coarse registration problems. In this paper, we propose a novel combined solution to automatically align two markerless point clouds from building scenes. Firstly, the method segments non-ground points from ground points. Secondly, the proposed method detects feature points from each cross section and then obtains semantic keypoints by connecting feature points with specific rules. Finally, the detected semantic keypoints from two point clouds act as inputs to a modified 4PCS algorithm. Examples are presented and the results compared with those of K-4PCS to demonstrate the main contributions of the proposed method, which are the extension of the original 4PCS to handle heavy datasets and the use of semantic keypoints to improve K-4PCS in relation to registration accuracy and computational efficiency.
Indian programme on middle atmosphere - Some results
NASA Astrophysics Data System (ADS)
Mitra, A. P.
An account of the very extensive program on the middle atmosphere carried out in India since 1982 is presented. Three rocket ranges (Thumba, SHAR and Balasore), a high altitude balloon facility at Hyderabad, a lidar at Thumba, a laser heterodyning system at Delhi, a meteor radar in Thumba, a network of UVB and multiwavelength radiometers, and a host of conventional ground based facilities scattered over the entire subcontinent were used. These facilities covered a range of latitudes from 8 deg N to 34 deg N and largely around the same longitude zone of 75 deg E. The nature of the Indian effort is the emphasis on campaign mode operations, knitting special rocket and balloon efforts with more conventional ground based activities around specific themes. Major campaigns carried out included: (1) Indo-Soviet Ozone Intercomparison campaigns in 1983 and 1987, (2) Aerosol campaign (3), Ionization and conductivity campaigns, (4) Equatorial Wave Campaign, (5) Antarctic Ozone Hole campaign in Dakshin Gangotri. A few of the more important findings are outlined.
Encircling the dark, a simple method to decipher the cosmos
NASA Astrophysics Data System (ADS)
Quirico, Eric
2017-09-01
Asteroids are relics of Solar System formation and host insightful information on physical, chemical, chronological and dynamical conditions that operated, since the formation of the first solids until the Late Heavy Bombardment. Since 2000, our view on these small objects has been deeply transformed due to several space missions and advances in ground-based observations. Near, Dawn (NASA) and Hayabusa 1 (JAXA) have provided extensive characterizations of the surface and interior of asteroids 433Eros, Itokawa, Vesta and Ceres, and revealed a complex morphology driven by collisions and/or internal activity. The samples returned to Earth by Hayabusa 1 provided a firm evidence of the genetic link between S-type asteroids and ordinary chondrites, and valuable clues on the first stage of space weathering. Meanwhile, ground-based observations, dynamical theory and meteoritics have drawn a big picture pointing to a continuum between asteroids and comets. Hopefully, the forthcoming missions Hayabusa2 and Osiris ReX will explore for the first time two C-type asteroids in the next years.
Pearson-Readhead survey from space
NASA Astrophysics Data System (ADS)
Preston, R. A.; Lister, M. L.; Tingay, S. J.; Piner, B. G.; Murphy, D. W.; Jones, D. L.; Meier, D. L.; Pearson, T. J.; Readhead, A. C. S.; Hirabayashi, H.; Kobayashi, H.; Inoue, M.
2001-01-01
We are using the VSOP space VLBI mission to observe a complete sample of Pearson-Readhead survey sources at 4.8 GHz to determine core brightness temperatures and pc-scale jet properties. The Pearson-Readhead sample has been used for extensive ground-based VLBI survey studies, and is ideal for a VSOP survey because the sources are strong, the VSOP u-v coverages are especially good above +35o declination, and multi-epoch ground-based VLBI data and other existing supporting data exceed that of any other sample. To date we have imaged 27 of the 31 objects in our sample. Our preliminary results show that the majority of objects contain strong core components that remain unresolved on baselines of ~30,000 km. The brightness temperatures of several cores significantly exceed 1012 K, which is indicative of highly relativistically beamed emission. We discuss correlations with several other beaming indicators, such as variability and spectral index, that support this scenario. This research was performed in part at the Jet Propulsion Laboratory, California Institute of Technology, under contract to NASA.
High resolution imaging at Palomar
NASA Technical Reports Server (NTRS)
Kulkarni, Shrinivas R.
1992-01-01
For the last two years we have embarked on a program of understanding the ultimate limits of ground-based optical imaging. We have designed and fabricated a camera specifically for high resolution imaging. This camera has now been pressed into service at the prime focus of the Hale 5 m telescope. We have concentrated on two techniques: the Non-Redundant Masking (NRM) and Weigelt's Fully Filled Aperture (FFA) method. The former is the optical analog of radio interferometry and the latter is a higher order extension of the Labeyrie autocorrelation method. As in radio Very Long Baseline Interferometry (VLBI), both these techniques essentially measure the closure phase and, hence, true image construction is possible. We have successfully imaged binary stars and asteroids with angular resolution approaching the diffraction limit of the telescope and image quality approaching that of a typical radio VLBI map. In addition, we have carried out analytical and simulation studies to determine the ultimate limits of ground-based optical imaging, the limits of space-based interferometric imaging, and investigated the details of imaging tradeoffs of beam combination in optical interferometers.
Vision-based localization for on-orbit servicing of a partially cooperative satellite
NASA Astrophysics Data System (ADS)
Oumer, Nassir W.; Panin, Giorgio; Mülbauer, Quirin; Tseneklidou, Anastasia
2015-12-01
This paper proposes ground-in-the-loop, model-based visual localization system based on transmitted images to ground, to aid rendezvous and docking maneuvers between a servicer and a target satellite. In particular, we assume to deal with a partially cooperative target, i.e. passive and without fiducial markers, but supposed at least to keep a controlled attitude, up to small fluctuations, so that the approach mainly involves translational motion. For the purpose of localization, video cameras provide an effective and relatively inexpensive solution, working at a wide range of distances with an increasing accuracy and robustness during the approach. However, illumination conditions in space are especially challenging, due to the direct sunlight exposure and to the glossy surface of a satellite, that creates strong reflections and saturations and therefore a high level of background clutter and missing detections. We employ a monocular camera for mid-range tracking (20 - 5 m) and stereo camera at close-range (5 - 0.5 m), with the respective detection and tracking methods, both using intensity edges and robustly dealing with the above issues. Our tracking system has been extensively verified at the facility of the European Proximity Operations Simulator (EPOS) of DLR, which is a very realistic ground simulation able to reproduce sunlight conditions through a high power floodlight source, satellite surface properties using multilayer insulation foils, as well as orbital motion trajectories with ground-truth data, by means of two 6 DOF industrial robots. Results from this large dataset show the effectiveness and robustness of our method against the above difficulties.
ERIC Educational Resources Information Center
Hollis, J. Michael
2013-01-01
In American context personal coaching and mentoring are used extensively in the fields of business, athletics and Christian discipleship. This one with one approach to personal improvement is applied in multiple contexts within education, business, athletics, discipleship, counseling, and parenting. This study implemented grounded theory…
USDA-ARS?s Scientific Manuscript database
It is desirable to be able to predict above ground biomass production indirectly, without extensive sampling or destructive harvesting. Leaf area index (LAI) is the amount of leaf surface area per ground area and is an important parameter in ecophysiology. As LAI increases, the photosynthetically ...
Federal Register 2010, 2011, 2012, 2013, 2014
2011-11-28
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Population trends and management opportunities for neotropical migrants
Chandler S. Robbins; John. R. Sauer; Bruce G. Peterjohn
1993-01-01
The Breeding Bird Survey shows that certain Neotropical migrant songbird populations have been declining over the past 26 years. Among them are forest birds that require extensive forest on the breeding grounds and also forested habitats on tropical wintering grounds. Other species have shown significant declines only since the early 1980's. Birds with broader...
Federal Register 2010, 2011, 2012, 2013, 2014
2010-08-19
... DEPARTMENT OF TRANSPORTATION Federal Highway Administration [Docket No. FHWA-2010-0104] Agency... Transportation, West Building Ground Floor, Room W12-140, 1200 New Jersey Avenue, SE., Washington, DC 20590. Hand Delivery or Courier: U.S. Department of Transportation, West Building Ground Floor, Room W12-140, 1200 New...
Skinner, R.H.; Wylie, B.K.; Gilmanov, T.G.
2011-01-01
Satellite-based normalized difference vegetation index (NDVI) data have been extensively used for estimating gross primary productivity (GPP) and yield of grazing lands throughout the world. However, the usefulness of satellite-based images for monitoring rotationally-grazed pastures in the northeastern United States might be limited because paddock size is often smaller than the resolution limits of the satellite image. This research compared NDVI data from satellites with data obtained using a ground-based system capable of fine-scale (submeter) NDVI measurements. Gross primary productivity was measured by eddy covariance on two pastures in central Pennsylvania from 2003 to 2008. Weekly 250-m resolution satellite NDVI estimates were also obtained for each pasture from the moderate resolution imaging spectroradiometer (MODIS) sensor. Ground-based NDVI data were periodically collected in 2006, 2007, and 2008 from one of the two pastures. Multiple-regression and regression-tree estimates of GPP, based primarily on MODIS 7-d NDVI and on-site measurements of photosynthetically active radiation (PAR), were generally able to predict growing-season GPP to within an average of 3% of measured values. The exception was drought years when estimated and measured GPP differed from each other by 11 to 13%. Ground-based measurements improved the ability of vegetation indices to capture short-term grazing management effects on GPP. However, the eMODIS product appeared to be adequate for regional GPP estimates where total growing-season GPP across a wide area would be of greater interest than short-term management-induced changes in GPP at individual sites.
NASA Astrophysics Data System (ADS)
Balin, I.; Jimenez, R.; Simeonov, V.; Ristori, P.; Navarette, M.; van den Bergh, H.; Calpini, B.
The assessment of the air pollution problems in term of understanding of the non- linear chemical mechanisms, the transport or the meteorological processes, and the choice of the abatement strategies could be based on the air pollution models. Nowa- days, very few of these models were validated due to the lack of 3D measurements. The goal of the ESCOMPTE experiment was to provide such of 3D database in order to constrain the air pollution models. The EPFL-LPA mobile laboratory was part of the ESCOMPTE extensive network and was located on the northern side of the Berre Lake at St.Chamas. In this framework, measurements of the air pollutants (O3, SO2, NOx, polycyclic aromatic hydrocarbons, black carbon and particulate matter of less than 10 microns mean diameter) and meteorological parameters (wind, temperature, pressure and relative humidity) were continuously performed from June 10 to July 13, 2001. They were combined with ground based lidar observations for ozone and aerosol estimation from 100m above ground level up to the free troposphere at ca.7 km agl. This paper will present an overview of the results obtained and will highlight one of the intensive observation period (IOP) during which clean air conditions were initially observed followed by highly polluted air masses during the second half of the IOP.
NASA Technical Reports Server (NTRS)
Campbell, James R.; Ge, Cui; Wang, Jun; Welton, Ellsworth J.; Bucholtz, Anthony; Hyer, Edward J.; Reid, Elizabeth A.; Chew, Boon Ning; Liew, Soo-Chin; Salinas, Santo V.;
2015-01-01
This work describes some of the most extensive ground-based observations of the aerosol profile collected in Southeast Asia to date, highlighting the challenges in simulating these observations with a mesoscale perspective. An 84-h WRF Model coupled with chemistry (WRF-Chem) mesoscale simulation of smoke particle transport at Kuching, Malaysia, in the southern Maritime Continent of Southeast Asia is evaluated relative to a unique collection of continuous ground-based lidar, sun photometer, and 4-h radiosonde profiling. The period was marked by relatively dry conditions, allowing smoke layers transported to the site unperturbed by wet deposition to be common regionally. The model depiction is reasonable overall. Core thermodynamics, including landsea-breeze structure, are well resolved. Total model smoke extinction and, by proxy, mass concentration are low relative to observation. Smoke emissions source products are likely low because of undersampling of fires in infrared sun-synchronous satellite products, which is exacerbated regionally by endemic low-level cloud cover. Differences are identified between the model mass profile and the lidar profile, particularly during periods of afternoon convective mixing. A static smoke mass injection height parameterized for this study potentially influences this result. The model does not resolve the convective mixing of aerosol particles into the lower free troposphere or the enhancement of near-surface extinction from nighttime cooling and hygroscopic effects.
Multi-Sensor Aerosol Products Sampling System
NASA Technical Reports Server (NTRS)
Petrenko, M.; Ichoku, C.; Leptoukh, G.
2011-01-01
Global and local properties of atmospheric aerosols have been extensively observed and measured using both spaceborne and ground-based instruments, especially during the last decade. Unique properties retrieved by the different instruments contribute to an unprecedented availability of the most complete set of complimentary aerosol measurements ever acquired. However, some of these measurements remain underutilized, largely due to the complexities involved in analyzing them synergistically. To characterize the inconsistencies and bridge the gap that exists between the sensors, we have established a Multi-sensor Aerosol Products Sampling System (MAPSS), which consistently samples and generates the spatial statistics (mean, standard deviation, direction and rate of spatial variation, and spatial correlation coefficient) of aerosol products from multiple spacebome sensors, including MODIS (on Terra and Aqua), MISR, OMI, POLDER, CALIOP, and SeaWiFS. Samples of satellite aerosol products are extracted over Aerosol Robotic Network (AERONET) locations as well as over other locations of interest such as those with available ground-based aerosol observations. In this way, MAPSS enables a direct cross-characterization and data integration between Level-2 aerosol observations from multiple sensors. In addition, the available well-characterized co-located ground-based data provides the basis for the integrated validation of these products. This paper explains the sampling methodology and concepts used in MAPSS, and demonstrates specific examples of using MAPSS for an integrated analysis of multiple aerosol products.
Simulating the effects of ground-water withdrawals on streamflow in a precipitation-runoff model
Zarriello, Philip J.; Barlow, P.M.; Duda, P.B.
2004-01-01
Precipitation-runoff models are used to assess the effects of water use and management alternatives on streamflow. Often, ground-water withdrawals are a major water-use component that affect streamflow, but the ability of surface-water models to simulate ground-water withdrawals is limited. As part of a Hydrologic Simulation Program-FORTRAN (HSPF) precipitation-runoff model developed to analyze the effect of ground-water and surface-water withdrawals on streamflow in the Ipswich River in northeastern Massachusetts, an analytical technique (STRMDEPL) was developed for calculating the effects of pumped wells on streamflow. STRMDEPL is a FORTRAN program based on two analytical solutions that solve equations for ground-water flow to a well completed in a semi-infinite, homogeneous, and isotropic aquifer in direct hydraulic connection to a fully penetrating stream. One analytical method calculates unimpeded flow at the stream-aquifer boundary and the other method calculates the resistance to flow caused by semipervious streambed and streambank material. The principle of superposition is used with these analytical equations to calculate time-varying streamflow depletions due to daily pumping. The HSPF model can readily incorporate streamflow depletions caused by a well or surface-water withdrawal, or by multiple wells or surface-water withdrawals, or both, as a combined time-varying outflow demand from affected channel reaches. These demands are stored as a time series in the Watershed Data Management (WDM) file. This time-series data is read into the model as an external source used to specify flow from the first outflow gate in the reach where these withdrawals are located. Although the STRMDEPL program can be run independently of the HSPF model, an extension was developed to run this program within GenScn, a scenario generator and graphical user interface developed for use with the HSPF model. This extension requires that actual pumping rates for each well be stored in a unique WDM dataset identified by an attribute that associates each well with the model reach from which water is withdrawn. Other attributes identify the type and characteristics of the data. The interface allows users to easily add new pumping wells, delete exiting pumping wells, or change properties of the simulated aquifer or well. Development of this application enhanced the ability of the HSPF model to simulate complex water-use conditions in the Ipswich River Basin. The STRMDEPL program and the GenScn extension provide a valuable tool for water managers to evaluate the effects of pumped wells on streamflow and to test alternative water-use scenarios. Copyright ASCE 2004.
NASA Astrophysics Data System (ADS)
Das, G. S.; Hazarika, P.; Goswami, U. D.
2018-07-01
We have studied the distribution patterns of lateral density, arrival time and angular position of Cherenkov photons generated in Extensive Air Showers (EASs) initiated by γ-ray, proton and iron primaries incident with various energies and at various zenith angles. This study is the extension of our earlier work [1] to cover a wide energy range of ground based γ-ray astronomy with a wide range of zenith angles (≤40°) of primary particles, as well as the extension to study the angular distribution patterns of Cherenkov photons in EASs. This type of study is important for distinguishing the γ-ray initiated showers from the hadronic showers in the ground based γ-ray astronomy, where Atmospheric Cherenkov Technique (ACT) is being used. Importantly, such study gives an insight on the nature of γ-ray and hadronic showers in general. In this work, the CORSIKA 6.990 simulation code is used for generation of EASs. Similarly to the case of Ref. [1], this study also revealed that, the lateral density and arrival time distributions of Cherenkov photons vary almost in accordance with the functions: ρch(r) =ρ0e-βr and tch(r) =t0eΓ/rλ respectively by taking different values of the parameters of functions for the type, energy and zenith angle of the primary particle. The distribution of Cherenkov photon's angular positions with respect to shower axis shows distinctive features depending on the primary type, its energy and the zenith angle. As a whole this distribution pattern for the iron primary is noticeably different from those for γ-ray and proton primaries. The value of the angular position at which the maximum number of Cherenkov photons are concentrated, increases with increase in energy of vertically incident primary, but for inclined primary it lies within a small value (≤1°) for almost all energies and primary types. No significant difference in the results obtained by using the high energy hadronic interaction models, viz., QGSJETII and EPOS has been observed.
Extension of the Kohn-Sham formulation of density functional theory to finite temperature
NASA Astrophysics Data System (ADS)
Gonis, A.; Däne, M.
2018-05-01
Based on Mermin's extension of the Hohenberg and Kohn theorems to non-zero temperature, the Kohn-Sham formulation of density functional theory (KS-DFT) is generalized to finite temperature. We show that present formulations are inconsistent with Mermin's functional containing expressions, in particular describing the Coulomb energy, that defy derivation and are even in violation of rules of logical inference. More; current methodology is in violation of fundamental laws of both quantum and classical mechanics. Based on this feature, we demonstrate the impossibility of extending the KS formalism to finite temperature through the self-consistent solutions of the single-particle Schrödinger equation of T > 0. Guided by the form of Mermin's functional that depends on the eigenstates of a Hamiltonian, determined at T = 0, we base our extension of KS-DFT on the determination of the excited states of a non-interacting system at the zero of temperature. The resulting formulation is consistent with that of Mermin constructing the free energy at T > 0 in terms of the excited states of a non-interacting Hamiltonian (system) that, within the KS formalism, are described by Slater determinants. To determine the excited states at T = 0 use is made of the extension of the Hohenberg and Kohn theorems to excited states presented in previous work applied here to a non-interacting collection of replicas of a non-interacting N-particle system, whose ground state density is taken to match that of K non-interacting replicas of an interacting N-particle system at T = 0 . The formalism allows for an ever denser population of the excitation spectrum of a Hamiltonian, within the KS approximation. The form of the auxiliary potential, (Kohn-Sham potential), is formally identical to that in the ground state formalism with the contribution of the Coulomb energy provided by the derivative of the Coulomb energy in all excited states taken into account. Once the excited states are determined, the minimum of the free energy within the KS formalism follows immediately in the form of Mermin's functional, but with the exact excited states in that functional represented by Slater determinants obtained through self-consistency conditions at the zero of temperature. It is emphasized that, in departure from all existing formulations, no self-consistency conditions are implemented at finite T; as we show, in fact, such formulations are rigorously blocked.
An intelligent, free-flying robot
NASA Technical Reports Server (NTRS)
Reuter, G. J.; Hess, C. W.; Rhoades, D. E.; Mcfadin, L. W.; Healey, K. J.; Erickson, J. D.; Phinney, Dale E.
1989-01-01
The ground based demonstration of the extensive extravehicular activity (EVA) Retriever, a voice-supervised, intelligent, free flying robot, is designed to evaluate the capability to retrieve objects (astronauts, equipment, and tools) which have accidentally separated from the Space Station. The major objective of the EVA Retriever Project is to design, develop, and evaluate an integrated robotic hardware and on-board software system which autonomously: (1) performs system activation and check-out; (2) searches for and acquires the target; (3) plans and executes a rendezvous while continuously tracking the target; (4) avoids stationary and moving obstacles; (5) reaches for and grapples the target; (6) returns to transfer the object; and (7) returns to base.
Daytime Water Detection by Fusing Multiple Cues for Autonomous Off-Road Navigation
NASA Technical Reports Server (NTRS)
Rankin, A. L.; Matthies, L. H.; Huertas, A.
2004-01-01
Detecting water hazards is a significant challenge to unmanned ground vehicle autonomous off-road navigation. This paper focuses on detecting the presence of water during the daytime using color cameras. A multi-cue approach is taken. Evidence of the presence of water is generated from color, texture, and the detection of reflections in stereo range data. A rule base for fusing water cues was developed by evaluating detection results from an extensive archive of data collection imagery containing water. This software has been implemented into a run-time passive perception subsystem and tested thus far under Linux on a Pentium based processor.
Monte Carlo Simulations and Generation of the SPI Response
NASA Technical Reports Server (NTRS)
Sturner, S. J.; Shrader, C. R.; Weidenspointner, G.; Teegarden, B. J.; Attie, D.; Diehl, R.; Ferguson, C.; Jean, P.; vonKienlin, A.
2003-01-01
In this paper we discuss the methods developed for the production of the INTEGRAL/SPI instrument response. The response files were produced using a suite of Monte Carlo simulation software developed at NASA/GSFC based on the GEANT-3 package available from CERN. The production of the INTEGRAL/SPI instrument response also required the development of a detailed computer mass model for SPI. We discuss our extensive investigations into methods to reduce both the computation time and storage requirements for the SPI response. We also discuss corrections to the simulated response based on our comparison of ground and inflight calibration data with MGEANT simulation.
Monte Carlo Simulations and Generation of the SPI Response
NASA Technical Reports Server (NTRS)
Sturner, S. J.; Shrader, C. R.; Weidenspointner, G.; Teegarden, B. J.; Attie, D.; Cordier, B.; Diehl, R.; Ferguson, C.; Jean, P.; vonKienlin, A.
2003-01-01
In this paper we discuss the methods developed for the production of the INTEGRAL/SPI instrument response. The response files were produced using a suite of Monte Carlo simulation software developed at NASA/GSFC based on the GEANT-3 package available from CERN. The production of the INTEGRAL/SPI instrument response also required the development of a detailed computer mass model for SPI. We discuss ow extensive investigations into methods to reduce both the computation time and storage requirements for the SPI response. We also discuss corrections to the simulated response based on our comparison of ground and infiight Calibration data with MGEANT simulations.
Experiment S001: Zodiacal Light Photography
NASA Technical Reports Server (NTRS)
Ney, E. P.; Huch, W. F.
1971-01-01
Observations made during the Gemini 5, 9, and 10 missions in the context of their relation to ground-based and balloon-based experiments on dim-light phenomena are reported. Zodiacal light is the visible manifestation of dust grains in orbit around the sun. The negatives that were exposed on the Gemini 9 mission were studied by the use of an isodensitracer to produce intensity isophotes. Data on the following factors were obtained: (1) intensity distribution of the zodiacal light, both morning and evening; (2) the height and intensity of the airglow at various geographic positions; and (3) intensity distribution of the Milky Way in the region of the sky near Cygnus. Also, a previously unreported phenomenon was discovered. This phenomenon appeared as an upward extension of the normal 90-kilometer airglow layer. The extension was in the form of wisps or plumes approximately 5 deg wide and extending upward approximately 5 deg. The results obtained from pictures exposed on the Gemini 10 mission were of qualitative or geometrical value only.
NASA Astrophysics Data System (ADS)
Jin, H.; Hao, J.; Chang, X.
2009-12-01
The proposed China-Russia Crude Oil Pipeline (CRCOP), 813 mm in diameter, is designed to transport 603,000 barrels of Siberian crude oil per day using conventional burial across 1,030 km of frozen-ground. About 500 boreholes, with depths of 5 to 20 m, were drilled and cored for analyses, and the frozen-ground conditions were evaluated. After detailed surveys and analyses of the permafrost conditions along the pipeline route, a conventional burial construction mode at a nominal depth of 1.5 m was adopted. This paper discusses the principles and criteria for the zonation and assessment of the frozen-ground environments and conditions of engineering geology for the design, construction, operation of the pipeline system based on an extensive and in-depth summary and analysis of the survey and exploration data. Full consideration of the characteristics of pipelining crude oil at ambient temperatures in the permafrost regions and the interactive processes between the pipeline and foundation soils were taken into account. Two zones of frozen-ground environment and conditions of engineering geology, i. e. seasonally-frozen-ground and permafrost, were defined on the basis of the regional distribution and differentiations in frozen-ground environments and conditions. Then, four subzones of the permafrost zone were classified according to the areal extent, taking into consideration the temperatures and thicknesses of permafrost, as well as changes in vegetation coverage. In the four subzones, 151 sections of engineering geology were categorized according to the ice/moisture contents of the permafrost, as well as the classes of frost-heaving and thaw-settlement potentials. These 151 sections are comprehensively summarized into four types for engineering construction and operation: good, fair, poor, and very poor, for overall conditions of engineering geology. The zonation, assessment principles and criteria have been applied in the design of the pipeline. They have also been used as the scientific bases for the construction, environmental management, operation and maintenance/contingency plans
Breakdown of the Wigner-Mattis theorem in semiconductor carbon-nanotube quantum dots
NASA Astrophysics Data System (ADS)
Rontani, Massimo; Secchi, Andrea; Manghi, Franca
2009-03-01
The Wigner-Mattis theorem states the ground state of two bound electrons, in the absence of the magnetic field, is always a spin-singlet. We predict the opposite result --a triplet- for two electrons in a quantum dot defined in a semiconductor carbon nanotube. The claim is supported by extensive many-body calculations based on the accurate configuration interaction code DONRODRIGO (www.s3.infm.t/donrodrigo). The crux of the matter is the peculiar two-valley structure of low-energy states, which encodes a pseudo-spin degree of freedom. The spin polarization of the ground state corresponds to a pseudo-spin singlet, which is selected by the inter-valley short-range Coulomb interaction. Single-electron excitation spectra and STM wave function images may validate this scenario, as shown by our numerical simulations.
A real-time freehand ultrasound calibration system with automatic accuracy feedback and control.
Chen, Thomas Kuiran; Thurston, Adrian D; Ellis, Randy E; Abolmaesumi, Purang
2009-01-01
This article describes a fully automatic, real-time, freehand ultrasound calibration system. The system was designed to be simple and sterilizable, intended for operating-room usage. The calibration system employed an automatic-error-retrieval and accuracy-control mechanism based on a set of ground-truth data. Extensive validations were conducted on a data set of 10,000 images in 50 independent calibration trials to thoroughly investigate the accuracy, robustness, and performance of the calibration system. On average, the calibration accuracy (measured in three-dimensional reconstruction error against a known ground truth) of all 50 trials was 0.66 mm. In addition, the calibration errors converged to submillimeter in 98% of all trials within 12.5 s on average. Overall, the calibration system was able to consistently, efficiently and robustly achieve high calibration accuracy with real-time performance.
Estimation of electric fields and current from ground-based magnetometer data
NASA Technical Reports Server (NTRS)
Kamide, Y.; Richmond, A. D.
1984-01-01
Recent advances in numerical algorithms for estimating ionospheric electric fields and currents from groundbased magnetometer data are reviewed and evaluated. Tests of the adequacy of one such algorithm in reproducing large-scale patterns of electrodynamic parameters in the high-latitude ionosphere have yielded generally positive results, at least for some simple cases. Some encouraging advances in producing realistic conductivity models, which are a critical input, are pointed out. When the algorithms are applied to extensive data sets, such as the ones from meridian chain magnetometer networks during the IMS, together with refined conductivity models, unique information on instantaneous electric field and current patterns can be obtained. Examples of electric potentials, ionospheric currents, field-aligned currents, and Joule heating distributions derived from ground magnetic data are presented. Possible directions for future improvements are also pointed out.
A Deep Neural Network Model for Rainfall Estimation UsingPolarimetric WSR-88DP Radar Observations
NASA Astrophysics Data System (ADS)
Tan, H.; Chandra, C. V.; Chen, H.
2016-12-01
Rainfall estimation based on radar measurements has been an important topic for a few decades. Generally, radar rainfall estimation is conducted through parametric algorisms such as reflectivity-rainfall relation (i.e., Z-R relation). On the other hand, neural networks are developed for ground rainfall estimation based on radar measurements. This nonparametric method, which takes into account of both radar observations and rainfall measurements from ground rain gauges, has been demonstrated successfully for rainfall rate estimation. However, the neural network-based rainfall estimation is limited in practice due to the model complexity and structure, data quality, as well as different rainfall microphysics. Recently, the deep learning approach has been introduced in pattern recognition and machine learning areas. Compared to traditional neural networks, the deep learning based methodologies have larger number of hidden layers and more complex structure for data representation. Through a hierarchical learning process, the high level structured information and knowledge can be extracted automatically from low level features of the data. In this paper, we introduce a novel deep neural network model for rainfall estimation based on ground polarimetric radar measurements .The model is designed to capture the complex abstractions of radar measurements at different levels using multiple layers feature identification and extraction. The abstractions at different levels can be used independently or fused with other data resource such as satellite-based rainfall products and/or topographic data to represent the rain characteristics at certain location. In particular, the WSR-88DP radar and rain gauge data collected in Dallas - Fort Worth Metroplex and Florida are used extensively to train the model, and for demonstration purposes. Quantitative evaluation of the deep neural network based rainfall products will also be presented, which is based on an independent rain gauge network.
Ground State and Finite Temperature Lanczos Methods
NASA Astrophysics Data System (ADS)
Prelovšek, P.; Bonča, J.
The present review will focus on recent development of exact- diagonalization (ED) methods that use Lanczos algorithm to transform large sparse matrices onto the tridiagonal form. We begin with a review of basic principles of the Lanczos method for computing ground-state static as well as dynamical properties. Next, generalization to finite-temperatures in the form of well established finite-temperature Lanczos method is described. The latter allows for the evaluation of temperatures T>0 static and dynamic quantities within various correlated models. Several extensions and modification of the latter method introduced more recently are analysed. In particular, the low-temperature Lanczos method and the microcanonical Lanczos method, especially applicable within the high-T regime. In order to overcome the problems of exponentially growing Hilbert spaces that prevent ED calculations on larger lattices, different approaches based on Lanczos diagonalization within the reduced basis have been developed. In this context, recently developed method based on ED within a limited functional space is reviewed. Finally, we briefly discuss the real-time evolution of correlated systems far from equilibrium, which can be simulated using the ED and Lanczos-based methods, as well as approaches based on the diagonalization in a reduced basis.
Space Link Extension (SLE) Emulation for High-Throughput Network Communication
NASA Technical Reports Server (NTRS)
Murawski, Robert W.; Tchorowski, Nicole; Golden, Bert
2014-01-01
As the data rate requirements for space communications increases, significant stress is placed not only on the wireless satellite communication links, but also on the ground networks which forward data from end-users to remote ground stations. These wide area network (WAN) connections add delay and jitter to the end-to-end satellite communication link, effects which can have significant impacts on the wireless communication link. It is imperative that any ground communication protocol can react to these effects such that the ground network does not become a bottleneck in the communication path to the satellite. In this paper, we present our SCENIC Emulation Lab testbed which was developed to test the CCSDS SLE protocol implementations proposed for use on future NASA communication networks. Our results show that in the presence of realistic levels of network delay, high-throughput SLE communication links can experience significant data rate throttling. Based on our observations, we present some insight into why this data throttling happens, and trace the probable issue back to non-optimal blocking communication which is sup-ported by the CCSDS SLE API recommended practices. These issues were presented as well to the SLE implementation developers which, based on our reports, developed a new release for SLE which we show fixes the SLE blocking issue and greatly improves the protocol throughput. In this paper, we also discuss future developments for our end-to-end emulation lab and how these improvements can be used to develop and test future space communication technologies.
Evaluation of Deep Learning Based Stereo Matching Methods: from Ground to Aerial Images
NASA Astrophysics Data System (ADS)
Liu, J.; Ji, S.; Zhang, C.; Qin, Z.
2018-05-01
Dense stereo matching has been extensively studied in photogrammetry and computer vision. In this paper we evaluate the application of deep learning based stereo methods, which were raised from 2016 and rapidly spread, on aerial stereos other than ground images that are commonly used in computer vision community. Two popular methods are evaluated. One learns matching cost with a convolutional neural network (known as MC-CNN); the other produces a disparity map in an end-to-end manner by utilizing both geometry and context (known as GC-net). First, we evaluate the performance of the deep learning based methods for aerial stereo images by a direct model reuse. The models pre-trained on KITTI 2012, KITTI 2015 and Driving datasets separately, are directly applied to three aerial datasets. We also give the results of direct training on target aerial datasets. Second, the deep learning based methods are compared to the classic stereo matching method, Semi-Global Matching(SGM), and a photogrammetric software, SURE, on the same aerial datasets. Third, transfer learning strategy is introduced to aerial image matching based on the assumption of a few target samples available for model fine tuning. It experimentally proved that the conventional methods and the deep learning based methods performed similarly, and the latter had greater potential to be explored.
NASA Astrophysics Data System (ADS)
Tagmann-Ioset, Aline; Schaub, Michael; Reichlin, Thomas S.; Weisshaupt, Nadja; Arlettaz, Raphaël
2012-02-01
Most farmland birds have declined significantly throughout the world due to agricultural intensification. Agri-environmental policies could not halt the decline of ground-foraging insectivorous farmland birds in Europe, indicating a gap in knowledge of species' ecological requirements. This represents a major impediment to the development of efficient, evidence-based agri-environmental measures. Using radio-tracking we studied habitat selection by farmland Hoopoes, a rare terrestrially foraging bird in Central Europe, and assessed habitat preferences of their main prey (Molecrickets), with the aim to identify optimal foraging habitat profiles in order to guide farmland management. Hierarchical logistic regression modelling of habitat descriptors at actual foraging locations vs. random locations within the home ranges of 13 males showed that the availability of bare ground was the principal determinant of foraging activity, with an optimum of 60-70% bare ground at patch scale. This ideal habitat configuration, which facilitates birds' terrestrial hunting, was found primarily in intensively farmed fruit tree plantations which dominated the landscape matrix: this habitat offers extensive strips of bare ground due to systematic removal of ground vegetation along tree rows. In contrast, dense grassland and cropland were avoided. Another important habitat feature was the availability of nongravelly soil, which enabled Hoopoes to probe the earth with their long, curved bill in search of underground invertebrates. The role of Molecrickets, however, appeared secondary to foraging patch selection, suggesting that prey accessibility was per se more important than prey abundance. Creating patches of bare ground within modern farmland where sufficient supplies of suitable invertebrate prey exist will support Hoopoe populations.
NASA Technical Reports Server (NTRS)
Hansen, Patricia A.
2003-01-01
The Hubble Space Telescope (HST) Space Telescope Imaging Spectrograph (STIS) was deployed on-orbit in February 1997. The contamination program for STIS was stringently controlled as the five-year end-of-life deposition was set at 158, per optical element. Contamination was controlled through materials selection, extensive vacuum outgassing certifications, cleaning techniques, and environmental controls. In addition to ground contamination controls, on-orbit contamination controls were implemented for both the HST servicing mission activities and early post-servicing mission checkout. The extensive contamination control program will be discussed and the STIS on-orbit data will be correlated with the prelaunch analytical predictions.
NASA Technical Reports Server (NTRS)
Woodbury, Sarah K.
2008-01-01
The introduction of United Space Alliance's Human Engineering Modeling and Performance Laboratory began in early 2007 in an attempt to address the problematic workspace design issues that the Space Shuttle has imposed on technicians performing maintenance and inspection operations. The Space Shuttle was not expected to require the extensive maintenance it undergoes between flights. As a result, extensive, costly resources have been expended on workarounds and modifications to accommodate ground processing personnel. Consideration of basic human factors principles for design of maintenance is essential during the design phase of future space vehicles, facilities, and equipment. Simulation will be needed to test and validate designs before implementation.
A strategy for in-flight measurements of physiology of pilots of high-performance fighter aircraft.
West, John B
2013-07-01
Some pilots flying modern high-performance fighter aircraft develop "hypoxia-like" incidents characterized by short periods of confusion and cognitive impairment. The problem is serious and recently led to the grounding of a fleet of aircraft. Extensive discussions of the incidents have taken place but some people believe that there is inadequate data to determine the cause. There is a tremendous disconnect between what is known about the function of the aircraft and the function of the pilot. This paper describes a plan for measuring the inspired and expired Po2 and Pco2 in the pilot's mask, the inspiratory flow rate, and pressure in the mask. A critically important requirement is that the interference with the function of the pilot is minimal. Although extensive physiological measurements were previously made on pilots in ground-based experiments such as rapid decompression in an altitude chamber and increased acceleration on a centrifuge, in-flight measurements of gas exchange have not been possible until now primarily because of the lack of suitable equipment. The present paper shows how the recent availability of small, rapidly responding oxygen and carbon dioxide analyzers make sophisticated in-flight measurements feasible. The added information has the potential of greatly improving our knowledge of pilot physiology, which could lead to an explanation for the incidents.
Novel knee joint mechanism of transfemoral prosthesis for stair ascent.
Inoue, Koh; Wada, Takahiro; Harada, Ryuchi; Tachiwana, Shinichi
2013-06-01
The stability of a transfemoral prosthesis when walking on flat ground has been established by recent advances in knee joint mechanisms and their control methods. It is, however, difficult for users of a transfemoral prosthesis to ascend stairs. This difficulty is mainly due to insufficient generation of extension moment around the knee joint of the prosthesis to lift the body to the next step on the staircase and prevent any unexpected flexion of the knee joint in the stance phase. Only a prosthesis with an actuator has facilitated stair ascent using a step-over-step gait (1 foot is placed per step). However, its use has issues associated with the durability, cost, maintenance, and usage environment. Therefore, the purpose of this research is to develop a novel knee joint mechanism for a prosthesis that generates an extension moment around the knee joint in the stance phase during stair ascent, without the use of any actuators. The proposed mechanism is based on the knowledge that the ground reaction force increases during the stance phase when the knee flexion occurs. Stair ascent experiments with the prosthesis showed that the proposed prosthesis can realize stair ascent without any undesirable knee flexion. In addition, the prosthesis is able to generate a positive knee joint moment power in the stance phase even without any power source.
New method to measure the attenuation of hadrons in extensive air showers
NASA Astrophysics Data System (ADS)
Apel, W. D.; Arteaga, J. C.; Badea, F.; Bekk, K.; Bertaina, M.; Blümer, J.; Bozdog, H.; Brancus, I. M.; Brüggemann, M.; Buchholz, P.; Cantoni, E.; Chiavassa, A.; Cossavella, F.; Daumiller, K.; de Souza, V.; di Pierro, F.; Doll, P.; Engel, R.; Engler, J.; Finger, M.; Fuhrmann, D.; Ghia, P. L.; Gils, H. J.; Glasstetter, R.; Grupen, C.; Haungs, A.; Heck, D.; Hildebrand, D.; Hörandel, J. R.; Huege, T.; Isar, P. G.; Kampert, K.-H.; Kang, D.; Kickelbick, D.; Klages, H. O.; Kolotaev, Y.; Łuczak, P.; Mathes, H. J.; Mayer, H. J.; Milke, J.; Mitrica, B.; Morello, C.; Navarra, G.; Nehls, S.; Oehlschläger, J.; Ostapchenko, S.; Over, S.; Petcu, M.; Pierog, T.; Rebel, H.; Roth, M.; Schieler, H.; Schröder, F.; Sima, O.; Stümpert, M.; Toma, G.; Trinchero, G. C.; Ulrich, H.; van Buren, J.; Walkowiak, W.; Weindl, A.; Wochele, J.; Wommer, M.; Zabierowski, J.
2009-07-01
Extensive air showers are generated through interactions of high-energy cosmic rays impinging the Earth’s atmosphere. A new method is described to infer the attenuation of hadrons in air showers. The numbers of electrons and muons, registered with the scintillator array of the KASCADE experiment, are used to estimate the energy of the shower inducing primary particle. A large hadron calorimeter is used to measure the hadronic energy reaching observation level. The ratio of energy reaching ground level to the energy of the primary particle is used to derive an attenuation length of hadrons in air showers. In the energy range from 106 to 3×107GeV the attenuation length obtained increases from 170 to 210g/cm2. The experimental results are compared to predictions of simulations based on contemporary high-energy interaction models.
NASA Technical Reports Server (NTRS)
Roelke, Richard J.
1992-01-01
Radial turbines have been used extensively in many applications including small ground based electrical power generators, automotive engine turbochargers and aircraft auxiliary power units. In all of these applications the turbine inlet temperature is limited to a value commensurate with the material strength limitations and life requirements of uncooled metal rotors. To take advantage of all the benefits that higher temperatures offer, such as increased turbine specific power output or higher cycle thermal efficiency, requires improved high temperature materials and/or blade cooling. Extensive research is on-going to advance the material properties of high temperature superalloys as well as composite materials including ceramics. The use of ceramics with their high temperature potential and low cost is particularly appealing for radial turbines. However until these programs reach fruition the only way to make significant step increases beyond the present material temperature barriers is to cool the radial blading.
Using simple environmental variables to estimate below-ground productivity in grasslands
Gill, R.A.; Kelly, R.H.; Parton, W.J.; Day, K.A.; Jackson, R.B.; Morgan, J.A.; Scurlock, J.M.O.; Tieszen, L.L.; Castle, J.V.; Ojima, D.S.; Zhang, X.S.
2002-01-01
In many temperate and annual grasslands, above-ground net primary productivity (NPP) can be estimated by measuring peak above-ground biomass. Estimates of below-ground net primary productivity and, consequently, total net primary productivity, are more difficult. We addressed one of the three main objectives of the Global Primary Productivity Data Initiative for grassland systems to develop simple models or algorithms to estimate missing components of total system NPP. Any estimate of below-ground NPP (BNPP) requires an accounting of total root biomass, the percentage of living biomass and annual turnover of live roots. We derived a relationship using above-ground peak biomass and mean annual temperature as predictors of below-ground biomass (r2 = 0.54; P = 0.01). The percentage of live material was 0.6, based on published values. We used three different functions to describe root turnover: constant, a direct function of above-ground biomass, or as a positive exponential relationship with mean annual temperature. We tested the various models against a large database of global grassland NPP and the constant turnover and direct function models were approximately equally descriptive (r2 = 0.31 and 0.37), while the exponential function had a stronger correlation with the measured values (r2 = 0.40) and had a better fit than the other two models at the productive end of the BNPP gradient. When applied to extensive data we assembled from two grassland sites with reliable estimates of total NPP, the direct function was most effective, especially at lower productivity sites. We provide some caveats for its use in systems that lie at the extremes of the grassland gradient and stress that there are large uncertainties associated with measured and modelled estimates of BNPP.
Numerical simulation of hydrothermal circulation in the Cascade Range, north-central Oregon
Ingebritsen, S.E.; Paulson, K.M.
1990-01-01
Alternate conceptual models to explain near-surface heat-flow observations in the central Oregon Cascade Range involve (1) an extensive mid-crustal magmatic heat source underlying both the Quaternary arc and adjacent older rocks or (2) a narrower deep heat source which is flanked by a relatively shallow conductive heat-flow anomaly caused by regional ground-water flow (the lateral-flow model). Relative to the mid-crustal heat source model, the lateral-flow model suggests a more limited geothermal resource base, but a better-defined exploration target. We simulated ground-water flow and heat transport through two cross sections trending west from the Cascade range crest in order to explore the implications of the two models. The thermal input for the alternate conceptual models was simulated by varying the width and intensity of a basal heat-flow anomaly and, in some cases, by introducing shallower heat sources beneath the Quaternary arc. Near-surface observations in the Breitenbush Hot Springs area are most readily explained in terms of lateral heat transport by regional ground-water flow; however, the deep thermal structure still cannot be uniquely inferred. The sparser thermal data set from the McKenzie River area can be explained either in terms of deep regional ground-water flow or in terms of a conduction-dominated system, with ground-water flow essentially confined to Quaternary rocks and fault zones.
Responses of buried corrugated metal pipes to earthquakes
DOE Office of Scientific and Technical Information (OSTI.GOV)
Davis, C.A.; Bardet, J.P.
2000-01-01
This study describes the results of field investigations and analyses carried out on 61 corrugated metal pipes (CMP) that were shaken by the 1994 Northridge earthquake. These CMPs, which include 29 small-diameter (below 107 cm) CMPs and 32 large-diameter (above 107 cm) CMPs, are located within a 10 km{sup 2} area encompassing the Van Normal Complex in the Northern San Fernando Valley, in Los Angeles, California. During the Northridge earthquake, ground movements were extensively recorded within the study area. Twenty-eight of the small-diameter CMPs performed well while the 32 large-diameter CMPs underwent performances ranging from no damage to complete collapse.more » The main cause of damage to the large-diameter CMPs was found to be the large ground strains. Based on this unprecedented data set, the factors controlling the seismic performance of the 32 large-diameter CMPs were identified and framed into a pseudostatic analysis method for evaluating the response of large diameter flexible underground pipes subjected to ground strain. The proposed analysis, which is applicable to transient and permanent strains, is capable of describing the observed performance of large-diameter CMPs during the 1994 Northridge earthquake. It indicates that peak ground velocity is a more reliable parameter for analyzing pipe damage than is peak ground acceleration. Results of this field investigation and analysis are useful for the seismic design and strengthening of flexible buried conduits.« less
Reflectance of a vegetation canopy using the Adding method
NASA Technical Reports Server (NTRS)
Cooper, K.; Smith, J. A.; Pitts, D.
1982-01-01
A modified vegetation reflectance model based on the Adding method is presented as a means to measure the interaction of shortwave radiation within a vegetation canopy. The canopy is conceptualized with reflecting and transmitting leaf facets, with the leaf orientations described by a leaf slope distribution, thereby yielding scattering matrices for canopy layers. The model predictions, when compared with ground-truth measurements, show good agreement except at visible wavelengths, where overestimations are observed. Conditions under which the model satisfies the reciprocity theorem are defined. Extension of the model by including azimuth is indicated.
Fire and vegetation history of the Jemez Mountains
Allen, Craig D.; Johnson, Peggy S.
2001-01-01
Historic patterns of fire occurrence and vegetation change in the Jemez Mountains of northern New Mexico have been described in detail by using multiple lines of evidence. Data sources include old aerial and ground-based photographs, historic records, charcoal deposits from bogs, fire-scarred trees (Figure 1), tree-ring reconstructions of precipitation, and field sampling of vegetation and soils. The forests and woodlands that cloak the Southwestern uplands provide the most extensive and detailed regional-scale network of fire history data available in the world (Swetnam and Baisan 1996, Swetnam et al. 1999, Allen 2002).
NASA's mobile satellite development program
NASA Technical Reports Server (NTRS)
Rafferty, William; Dessouky, Khaled; Sue, Miles
1988-01-01
A Mobile Satellite System (MSS) will provide data and voice communications over a vast geographical area to a large population of mobile users. A technical overview is given of the extensive research and development studies and development performed under NASA's mobile satellite program (MSAT-X) in support of the introduction of a U.S. MSS. The critical technologies necessary to enable such a system are emphasized: vehicle antennas, modulation and coding, speech coders, networking and propagation characterization. Also proposed is a first, and future generation MSS architecture based upon realized ground segment equipment and advanced space segment studies.
A Dust Aggregation and Concentration System (DACS) for the Microgravity Space Environment
NASA Technical Reports Server (NTRS)
Giovane, F. J.; Blum, J.
1999-01-01
The Dust Aggregation and Concentration System, DACS, Project is an international effort intended to complete the preliminary definition of a system for suspending and concentrating dust particles in a microgravity environment for extended periods of time. The DACS design concept is based on extensive ground, drop tower, and parabolic flight tests. During the present proposed work, the DACS design will be completed, and a Science Requirements Document generated. At the end of the proposed 2 year project, DACS will be positioned to enter the advanced definition phase.
Rats and bunnies: core kids in an American mall.
Lewis, G H
1989-01-01
Although adolescents use shopping malls as important places of congregation, very little attention has been paid to this phenomenon by social scientists. This paper reports on a qualitative, interview-based study of adolescents in a New England shopping mall. Regular, day-to-day frequenters (N = 23) were identified and interviewed extensively over a six-week period in 1988. These "core kids" exhibited a good deal of alienation from both family and school, and used the mall as a neutral ground on which to create a fragile but mutually supportive community of kind.
Localization of an experimental ecological unit in the Maradi region of Nigeria
NASA Technical Reports Server (NTRS)
Mainguet, M.; Canon, L.; Chapelle, A. M.
1977-01-01
A detailed topographical and geomorphological description of a specific ecological unit in the Maradi region of the Sahel in the Niger Republic is presented. Sandy structures are classified into active dunes and covered dunes and an extensives vocabulary is developed to describe sub-categories. The descriptions are based on meteorological data (anemometric and rainfall) from local weather stations, ground observations, aerial photographs and LANDSAT pictures. The problem of dune reactivation and desertification is discussed both from the standpoint of causes and possible counter measures.
NASA Technical Reports Server (NTRS)
Sanders, Felicia A.; Jones, Grailing, Jr.; Levesque, Michael
2006-01-01
The CCSDS File Delivery Protocol (CFDP) Standard could reshape ground support architectures by enabling applications to communicate over the space link using reliable-symmetric transport services. JPL utilized the CFDP standard to support the Deep Impact Mission. The architecture was based on layering the CFDP applications on top of the CCSDS Space Link Extension Services for data transport from the mission control centers to the ground stations. On July 4, 2005 at 1:52 A.M. EDT, the Deep Impact impactor successfully collided with comet Tempel 1. During the final 48 hours prior to impact, over 300 files were uplinked to the spacecraft, while over 6 thousand files were downlinked from the spacecraft using the CFDP. This paper uses the Deep Impact Mission as a case study in a discussion of the CFDP architecture, Deep Impact Mission requirements, and design for integrating the CFDP into the JPL deep space support services. Issues and recommendations for future missions using CFDP are also provided.
39 CFR 962.21 - Appeal of initial decision to judicial officer.
Code of Federal Regulations, 2010 CFR
2010-07-01
... request for an extension within the initial 30-day period and demonstrates good cause for such extension... is material and that there were reasonable grounds for the failure to present such evidence, the... issued unless a petition for judicial review is filed. [52 FR 12904, Apr. 20, 1987, as amended at 67 FR...
Dynamic sensor management of dispersed and disparate sensors for tracking resident space objects
NASA Astrophysics Data System (ADS)
El-Fallah, A.; Zatezalo, A.; Mahler, R.; Mehra, R. K.; Donatelli, D.
2008-04-01
Dynamic sensor management of dispersed and disparate sensors for space situational awareness presents daunting scientific and practical challenges as it requires optimal and accurate maintenance of all Resident Space Objects (RSOs) of interest. We demonstrate an approach to the space-based sensor management problem by extending a previously developed and tested sensor management objective function, the Posterior Expected Number of Targets (PENT), to disparate and dispersed sensors. This PENT extension together with observation models for various sensor platforms, and a Probability Hypothesis Density Particle Filter (PHD-PF) tracker provide a powerful tool for tackling this challenging problem. We demonstrate the approach using simulations for tracking RSOs by a Space Based Visible (SBV) sensor and ground based radars.
Remote sensing for grassland management in the arid Southwest
Marsett, R.C.; Qi, J.; Heilman, P.; Biedenbender, S.H.; Watson, M.C.; Amer, S.; Weltz, M.; Goodrich, D.; Marsett, R.
2006-01-01
We surveyed a group of rangeland managers in the Southwest about vegetation monitoring needs on grassland. Based on their responses, the objective of the RANGES (Rangeland Analysis Utilizing Geospatial Information Science) project was defined to be the accurate conversion of remotely sensed data (satellite imagery) to quantitative estimates of total (green and senescent) standing cover and biomass on grasslands and semidesert grasslands. Although remote sensing has been used to estimate green vegetation cover, in arid grasslands herbaceous vegetation is senescent much of the year and is not detected by current remote sensing techniques. We developed a ground truth protocol compatible with both range management requirements and Landsat's 30 m resolution imagery. The resulting ground-truth data were then used to develop image processing algorithms that quantified total herbaceous vegetation cover, height, and biomass. Cover was calculated based on a newly developed Soil Adjusted Total Vegetation Index (SATVI), and height and biomass were estimated based on reflectance in the near infrared (NIR) band. Comparison of the remotely sensed estimates with independent ground measurements produced r2 values of 0.80, 0.85, and 0.77 and Nash Sutcliffe values of 0.78, 0.70, and 0.77 for the cover, plant height, and biomass, respectively. The approach for estimating plant height and biomass did not work for sites where forbs comprised more than 30% of total vegetative cover. The ground reconnaissance protocol and image processing techniques together offer land managers accurate and timely methods for monitoring extensive grasslands. The time-consuming requirement to collect concurrent data in the field for each image implies a need to share the high fixed costs of processing an image across multiple users to reduce the costs for individual rangeland managers.
Data Gathering and Energy Transfer Dilemma in UAV-Assisted Flying Access Network for IoT.
Arabi, Sara; Sabir, Essaid; Elbiaze, Halima; Sadik, Mohamed
2018-05-11
Recently, Unmanned Aerial Vehicles (UAVs) have emerged as an alternative solution to assist wireless networks, thanks to numerous advantages they offer in comparison to terrestrial fixed base stations. For instance, a UAV can be used to embed a flying base station providing an on-demand nomadic access to network services. A UAV can also be used to wirelessly recharge out-of-battery ground devices. In this paper, we aim to deal with both data collection and recharging depleted ground Internet-of-Things (IoT) devices through a UAV station used as a flying base station. To extend the network lifetime, we present a novel use of UAV with energy harvesting module and wireless recharging capabilities. However, the UAV is used as an energy source to empower depleted IoT devices. On one hand, the UAV charges depleted ground IoT devices under three policies: (1) low-battery first scheme; (2) high-battery first scheme; and (3) random scheme. On the other hand, the UAV station collects data from IoT devices that have sufficient energy to transmit their packets, and in the same phase, the UAV exploits the Radio Frequency (RF) signals transmitted by IoT devices to extract and harvest energy. Furthermore, and as the UAV station has a limited coverage time due to its energy constraints, we propose and investigate an efficient trade-off between ground users recharging time and data gathering time. Furthermore, we suggest to control and optimize the UAV trajectory in order to complete its travel within a minimum time, while minimizing the energy spent and/or enhancing the network lifetime. Extensive numerical results and simulations show how the system behaves under different scenarios and using various metrics in which we examine the added value of UAV with energy harvesting module.
Picon-Cochard, Catherine; Coll, Lluis; Balandier, Philippe
2006-06-01
In abandoned or extensively managed grasslands, the mechanisms involved in pioneer tree species success are not fully explained. Resource competition among plants and microclimate modifications have been emphasised as possible mechanisms to explain variation of survivorship and growth. In this study, we evaluated a number of mechanisms that may lead to successful survival and growth of seedlings of a pioneer tree species (Pinus sylvestris) in a grass-dominated grassland. Three-year-old Scots pines were planted in an extensively managed grassland of the French Massif Central and for 2 years were either maintained in bare soil or subjected to aerial and below-ground interactions induced by grass vegetation. Soil temperatures were slightly higher in bare soil than under the grass vegetation, but not to an extent explaining pine growth differences. The tall grass canopy reduced light transmission by 77% at ground level and by 20% in the upper part of Scots pine seedlings. Grass vegetation presence also significantly decreased soil volumetric water content (Hv) and soil nitrate in spring and in summer. In these conditions, the average tree height was reduced by 5% compared to trees grown in bare soil, and plant biomass was reduced by 85%. Scots pine intrinsic water-use efficiency (A/g), measured by leaf gas-exchange, increased when Hv decreased owing to a rapid decline of stomatal conductance (g). This result was also confirmed by delta 13C analyses of needles. A summer 15N labelling of seedlings and grass vegetation confirmed the higher NO3 capture capacity of grass vegetation in comparison with Scots pine seedlings. Our results provide evidence that the seedlings' success was linked to tolerance of below-ground resource depletion (particularly water) induced by grass vegetation based on morphological and physiological plasticity as well as to resource conservation.
Mission Operations with an Autonomous Agent
NASA Technical Reports Server (NTRS)
Pell, Barney; Sawyer, Scott R.; Muscettola, Nicola; Smith, Benjamin; Bernard, Douglas E.
1998-01-01
The Remote Agent (RA) is an Artificial Intelligence (AI) system which automates some of the tasks normally reserved for human mission operators and performs these tasks autonomously on-board the spacecraft. These tasks include activity generation, sequencing, spacecraft analysis, and failure recovery. The RA will be demonstrated as a flight experiment on Deep Space One (DSI), the first deep space mission of the NASA's New Millennium Program (NMP). As we moved from prototyping into actual flight code development and teamed with ground operators, we made several major extensions to the RA architecture to address the broader operational context in which PA would be used. These extensions support ground operators and the RA sharing a long-range mission profile with facilities for asynchronous ground updates; support ground operators monitoring and commanding the spacecraft at multiple levels of detail simultaneously; and enable ground operators to provide additional knowledge to the RA, such as parameter updates, model updates, and diagnostic information, without interfering with the activities of the RA or leaving the system in an inconsistent state. The resulting architecture supports incremental autonomy, in which a basic agent can be delivered early and then used in an increasingly autonomous manner over the lifetime of the mission. It also supports variable autonomy, as it enables ground operators to benefit from autonomy when L'@ey want it, but does not inhibit them from obtaining a detailed understanding and exercising tighter control when necessary. These issues are critical to the successful development and operation of autonomous spacecraft.
A knowledge-based framework for image enhancement in aviation security.
Singh, Maneesha; Singh, Sameer; Partridge, Derek
2004-12-01
The main aim of this paper is to present a knowledge-based framework for automatically selecting the best image enhancement algorithm from several available on a per image basis in the context of X-ray images of airport luggage. The approach detailed involves a system that learns to map image features that represent its viewability to one or more chosen enhancement algorithms. Viewability measures have been developed to provide an automatic check on the quality of the enhanced image, i.e., is it really enhanced? The choice is based on ground-truth information generated by human X-ray screening experts. Such a system, for a new image, predicts the best-suited enhancement algorithm. Our research details the various characteristics of the knowledge-based system and shows extensive results on real images.
Faber, G S; Chang, C C; Kingma, I; Dennerlein, J T; van Dieën, J H
2016-04-11
Inertial motion capture (IMC) systems have become increasingly popular for ambulatory movement analysis. However, few studies have attempted to use these measurement techniques to estimate kinetic variables, such as joint moments and ground reaction forces (GRFs). Therefore, we investigated the performance of a full-body ambulatory IMC system in estimating 3D L5/S1 moments and GRFs during symmetric, asymmetric and fast trunk bending, performed by nine male participants. Using an ambulatory IMC system (Xsens/MVN), L5/S1 moments were estimated based on the upper-body segment kinematics using a top-down inverse dynamics analysis, and GRFs were estimated based on full-body segment accelerations. As a reference, a laboratory measurement system was utilized: GRFs were measured with Kistler force plates (FPs), and L5/S1 moments were calculated using a bottom-up inverse dynamics model based on FP data and lower-body kinematics measured with an optical motion capture system (OMC). Correspondence between the OMC+FP and IMC systems was quantified by calculating root-mean-square errors (RMSerrors) of moment/force time series and the interclass correlation (ICC) of the absolute peak moments/forces. Averaged over subjects, L5/S1 moment RMSerrors remained below 10Nm (about 5% of the peak extension moment) and 3D GRF RMSerrors remained below 20N (about 2% of the peak vertical force). ICCs were high for the peak L5/S1 extension moment (0.971) and vertical GRF (0.998). Due to lower amplitudes, smaller ICCs were found for the peak asymmetric L5/S1 moments (0.690-0.781) and horizontal GRFs (0.559-0.948). In conclusion, close correspondence was found between the ambulatory IMC-based and laboratory-based estimates of back load. Copyright © 2015 Elsevier Ltd. All rights reserved.
Sydney T. Bacchus; Toshihide Hamazaki; Bruce L. Haines
2000-01-01
Pond-cypress, a deciduous conifer , is a dominant canopy species in depressional wetlands of the southeastern Coastal Plain (SCP). Extensive premature decline and death of pond-cypress trees in central Florida have been attributed to hydroperiod alterations due to excessive withdrawals of ground water from the Floridan aquifer. One factor identified in the decline...
NASA Technical Reports Server (NTRS)
Rignot, Eric
1997-01-01
Ice Sheet grounding lines are sensitive indicator of changes in ice thickness, sea level or elevation of the sea bed. Here, we use the synthetic-aperture radar interferometry technique to detect the migration of thel imit of tidal flexing, or hinge line, of Petermann Gletscher, a major outlet glacier of north Greenland which develops an extensive floating tongue.
Computational solution of atmospheric chemistry problems
NASA Technical Reports Server (NTRS)
Jafri, J.; Ake, R. L.
1986-01-01
Extensive studies were performed on problems of interest in atmospheric chemistry. In addition to several minor projects, four major projects were performed and described (theoretical studies of ground and low-lying excited states of ClO2; ground and excited state potential energy surfaces of the methyl peroxy radical; electronic states ot the FO radical; and theoretical studies S02 (H2O) (sub n)).
Ground System Extensibility Considerations
NASA Astrophysics Data System (ADS)
Miller, S. W.; Greene, E.
2017-12-01
The National Oceanic and Atmospheric Administration (NOAA) and National Aeronautics and Space Administration (NASA) are jointly acquiring the next-generation civilian weather and environmental satellite system: the Joint Polar Satellite System (JPSS). The Joint Polar Satellite System will replace the afternoon orbit component and ground processing system of the current Polar-orbiting Operational Environmental Satellites (POES) managed by NOAA. The JPSS satellites will carry a suite of sensors designed to collect meteorological, oceanographic, climatological and geophysical observations of the Earth. The ground processing system for JPSS is known as the JPSS Common Ground System (JPSS CGS). Developed and maintained by Raytheon Intelligence, Information and Services (IIS), the CGS is a multi-mission enterprise system serving NOAA, NASA and their national and international partners, such as NASA's Earth Observation System (EOS), NOAA's current POES, the Japan Aerospace Exploration Agency's (JAXA) Global Change Observation Mission - Water (GCOM-W1), and DoD's Defense Meteorological Satellite Program (DMSP). The CGS provides a wide range of support to a number of national and international missions, including command and control, mission management, data acquisition and routing, and environmental data processing and distribution. The current suite of CGS-supported missions has demonstrated the value of interagency and international partnerships to address global observation needs. With its established infrastructure and existing suite of missions, the CGS is extensible to a wider array of potential new missions. This paper will describe how the inherent scalability and extensibility of the CGS enables the addition of these new missions, with an eye on global enterprise needs in the 2020's and beyond.
NASA Technical Reports Server (NTRS)
McLaughlin, Brian J.; Barrett, Larry K.
2012-01-01
Common practice in the development of simulation systems is meeting all user requirements within a single instantiation. The Joint Polar Satellite System (JPSS) presents a unique challenge to establish a simulation environment that meets the needs of a diverse user community while also spanning a multi-mission environment over decades of operation. In response, the JPSS Flight Vehicle Test Suite (FVTS) is architected with an extensible infrastructure that supports the operation of multiple observatory simulations for a single mission and multiple mission within a common system perimeter. For the JPSS-1 satellite, multiple fidelity flight observatory simulations are necessary to support the distinct user communities consisting of the Common Ground System development team, the Common Ground System Integration & Test team, and the Mission Rehearsal Team/Mission Operations Team. These key requirements present several challenges to FVTS development. First, the FVTS must ensure all critical user requirements are satisfied by at least one fidelity instance of the observatory simulation. Second, the FVTS must allow for tailoring of the system instances to function in diverse operational environments from the High-security operations environment at NOAA Satellite Operations Facility (NSOF) to the ground system factory floor. Finally, the FVTS must provide the ability to execute sustaining engineering activities on a subset of the system without impacting system availability to parallel users. The FVTS approach of allowing for multiple fidelity copies of observatory simulations represents a unique concept in simulator capability development and corresponds to the JPSS Ground System goals of establishing a capability that is flexible, extensible, and adaptable.
Synthetic fuels for ground transportation with special emphasis on hydrogen
NASA Technical Reports Server (NTRS)
Singh, J. J.
1975-01-01
The role of various synthetic fuels, for ground transportation in the United States, was examined for the near term (by 1985) and the longer term applications (1985-2000 and beyond 2000). Feasible options include synthetic oil, methanol, electric propulsion, and hydrogen. It is concluded that (1) the competition during the next 50 years will be for the fuels of all types, rather than among the fuels; (2) extensive domestic oil and gas exploration should be initiated concurrent with the development of several alternate fuels and related ancillaries; and (3) hydrogen, as an automotive fuel, seems to be equivalent to gasoline for optimum fuel to air mixtures. As a pollution free, high energy density fuel, hydrogen deserves consideration as the logical replacement for the hydrocarbons. Several research and development requirements, essential for the implementation of hydrogen economy for ground transportation, were identified. Extensive engineering development and testing activities should be initiated to establish hydrogen as the future automotive fuel, followed by demonstration projects and concerted efforts at public education.
Extensive air showers, lightning, and thunderstorm ground enhancements
NASA Astrophysics Data System (ADS)
Chilingarian, A.; Hovsepyan, G.; Kozliner, L.
2016-09-01
For lightning research, we monitor particle fluxes from thunderclouds, the so-called thunderstorm ground enhancements (TGEs) initiated by runaway electrons, and extensive air showers (EASs) originating from high-energy protons or fully stripped nuclei that enter the Earth's atmosphere. We also monitor the near-surface electric field and atmospheric discharges using a network of electric field mills. The Aragats "electron accelerator" produced several TGEs and lightning events in the spring of 2015. Using 1-s time series, we investigated the relationship between lightning and particle fluxes. Lightning flashes often terminated the particle flux; in particular, during some TGEs, lightning events would terminate the particle flux thrice after successive recovery. It was postulated that a lightning terminates a particle flux mostly in the beginning of a TGE or in its decay phase; however, we observed two events (19 October 2013 and 20 April 2015) when the huge particle flux was terminated just at the peak of its development. We discuss the possibility of a huge EAS facilitating lightning leader to find its path to the ground.
Chemical quality of ground water in the central Sacramento Valley, California
Fogelman, Ronald P.
1978-01-01
The study area includes about 1,200 square miles in the central Sacramento Valley adjacent to the Sacramento River from Knights Landing to Los Molinos, Calif. With recent agricultural development in the area, additional land has been brought under irrigation from land which had been used primarily for dry farming and grazing. This report documents the chemical character of the ground water prior to water-level declines resulting from extensive pumping for irrigation or to changes caused by extensive use of imported surface water. Chemical analyses of samples from 209 wells show that most of the area is underlain by ground water of a quality suitable for most agricultural and domestic purposes. Most of the water sampled in the area has dissolved-solids concentrations ranging from 100 to 700 milligrams per liter. The general water types for the area are a calcium magnesium bicarbonate or magnesium calcium bicarbonate and there are negligible amounts of toxic trace elements. (Woodard-USGS)
Krause, Richard E.; Matthews, Sharon E.; Gill, Harold E.
1984-01-01
A compilation of ground-water data that have been collected for nearly 100 years in the coastal area of Georgia as part of cooperative activities between the U.S. Geological Survey and other agencies is presented in this report. The compilation of pertinent data indicates that information is available for use in the evaluation of the ground-water resources of the 13 counties of coastal Georgia. Included in this report is a fairly complete discussion of previous and ongoing investigations and monitoring networks, and an extensive list of references. Maps at 1:24,000, 1:100,000; and 1:1000,000 scales contain well locations and identifers for all wells in the Ground Water Site Inventory (GWSI) data base of the National Water Data Storage and Retrieval System (WATSTORE). Tabular summaries of selected site information from GWSI, including well identifiers and names , latitude-longitude location, depth of well, altitude of land surface, and use of water are presented. Water-use data from the National Water Use Data System, and water use for irrigation from the University of Georgia, Department of Agriculture survey , are tabulated. Also included are pertinent information on geophysical surveys and data obtained, and proposed project activities, particularly test-monitor well drilling.
Small Scale Polygons and the History of Ground Ice on Mars
NASA Technical Reports Server (NTRS)
Mellon, Michael T.
2003-01-01
Recent progress on polygon modeling has focused on the diameter and surface relief that we expect of thermal-contraction polygons in martian permafrost. With this in mind, we developed a finite-element model of thermal-contraction-crack behavior in permafrost in a martian climate. This model was generated from a finite element code by Jay Melosh (called TECTON) originally developed for terrestrial and planetary crustal-deformation studies. We adapted this model to martian permafrost by including time (and temperature) dependent rheologies, boundary conditions, and isotropic thermal-contraction, as well as several small adaptations to a martian environment. We tested our model extensively, including comparison to an analytic solution of pre-fracture stress. We recently published an analysis of two potential sources of water for forming the recent gullies. In this work we first evaluated the potential for near-surface ground ice (in the top meter or so of soil) to melt under conditions of solar heating on sloped surfaces at high obliquity, utilizing both thermal and diffusion-based ground-ice-stability models; our results suggested that the ground ice will sublimate, and the ice table will recede to greater depths before the melting temperature can be reached. An exception can occur only for extremely salt-rich ice, depressing the freezing point.
A new fabrication method for precision antenna reflectors for space flight and ground test
NASA Technical Reports Server (NTRS)
Sharp, G. Richard; Wanhainen, Joyce S.; Ketelsen, Dean A.
1991-01-01
Communications satellites are using increasingly higher frequencies that require increasingly precise antenna reflectors for use in space. Traditional industry fabrication methods for space antenna reflectors employ successive modeling techniques using high- and low-temperature molds for reflector face sheets and then a final fit-up of the completed honeycomb sandwich panel antenna reflector to a master pattern. However, as new missions are planned at much higher frequencies, greater accuracies will be necessary than are achievable using these present methods. A new approach for the fabrication of ground-test solid-surface antenna reflectors is to build a rigid support structure with an easy-to-machine surface. This surface is subsequently machined to the desired reflector contour and coated with a radio-frequency-reflective surface. This method was used to fabricate a 2.7-m-diameter ground-test antenna reflector to an accuracy of better than 0.013 mm (0.0005 in.) rms. A similar reflector for use on spacecraft would be constructed in a similar manner but with space-qualified materials. The design, analysis, and fabrication of the 2.7-m-diameter precision antenna reflector for antenna ground tests and the extension of this technology to precision, space-based antenna reflectors are described.
Bezodis, Neil E; North, Jamie S; Razavet, Jane L
2017-09-01
A more horizontally oriented ground reaction force vector is related to higher levels of sprint acceleration performance across a range of athletes. However, the effects of acute experimental alterations to the force vector orientation within athletes are unknown. Fifteen male team sports athletes completed maximal effort 10-m accelerations in three conditions following different verbal instructions intended to manipulate the force vector orientation. Ground reaction forces (GRFs) were collected from the step nearest 5-m and stance leg kinematics at touchdown were also analysed to understand specific kinematic features of touchdown technique which may influence the consequent force vector orientation. Magnitude-based inferences were used to compare findings between conditions. There was a likely more horizontally oriented ground reaction force vector and a likely lower peak vertical force in the control condition compared with the experimental conditions. 10-m sprint time was very likely quickest in the control condition which confirmed the importance of force vector orientation for acceleration performance on a within-athlete basis. The stance leg kinematics revealed that a more horizontally oriented force vector during stance was preceded at touchdown by a likely more dorsiflexed ankle, a likely more flexed knee, and a possibly or likely greater hip extension velocity.
Ground-water monitoring in the Albuquerque area
Thorn, Condé R.
1996-01-01
At present (1996), all drinking water for Albuquerque residents comes from ground-water reserves. The Albuquerque area is the largest population center in the State and the largest consumer of ground water. Recent reports concerning the water resources of the Albuquerque area suggest that the Albuquerque Basin may soon face serious water-availability and water-quality problems due to anticipated ground-water development. Recent studies completed by the U.S. Geological Survey (USGS) have improved the understanding of the ground-water resources in the Albuquerque Basin. These studies have indicated that the more permeable units within the aquifer system--the upper Santa Fe Group--are less extensive than previously thought, and that water-levels have declined as much as 160 feet.
On-board congestion control for satellite packet switching networks
NASA Technical Reports Server (NTRS)
Chu, Pong P.
1991-01-01
It is desirable to incorporate packet switching capability on-board for future communication satellites. Because of the statistical nature of packet communication, incoming traffic fluctuates and may cause congestion. Thus, it is necessary to incorporate a congestion control mechanism as part of the on-board processing to smooth and regulate the bursty traffic. Although there are extensive studies on congestion control for both baseband and broadband terrestrial networks, these schemes are not feasible for space based switching networks because of the unique characteristics of satellite link. Here, we propose a new congestion control method for on-board satellite packet switching. This scheme takes into consideration the long propagation delay in satellite link and takes advantage of the the satellite's broadcasting capability. It divides the control between the ground terminals and satellite, but distributes the primary responsibility to ground terminals and only requires minimal hardware resource on-board satellite.
Experimental land observing data system feasibility study
NASA Technical Reports Server (NTRS)
Buckley, J. L.; Kraiman, H.
1982-01-01
An end-to-end data system to support a Shuttle-based Multispectral Linear Array (MLA) mission in the mid-1980's was defined. The experimental Land Observing System (ELOS) is discussed. A ground system that exploits extensive assets from the LANDSAT-D Program to effectively meet the objectives of the ELOS Mission was defined. The goal of 10 meter pixel precision, the variety of data acquisition capabilities, and the use of Shuttle are key to the mission requirements, Ground mission management functions are met through the use of GSFC's Multi-Satellite Operations Control Center (MSOCC). The MLA Image Generation Facility (MIGF) combines major hardware elements from the Applications Development Data System (ADDS) facility and LANDSAT Assessment System (LAS) with a special purpose MLA interface unit. LANDSAT-D image processing techniques, adapted to MLA characteristics, form the basis for the use of existing software and the definition of new software required.
Biomass Burning Airborne and Spaceborne Experiment in the Amazonas (BASE-A)
NASA Technical Reports Server (NTRS)
Kaufman, Y. J.; Setzer, A.; Ward, D.; Tanre, D.; Holben, B. N.; Menzel, P.; Pereira, M. C.; Rasmussen, R.
1992-01-01
Results are presented on measurements of the trace gas and particulate matter emissions due to biomass burning during deforestation and grassland fires in South America, conducted as part of the Biomass Burning Airborne and Spaceborne Experiment in the Amazonas in September 1989. Field observations by an instrumented aircraft were used to estimate concentrations of O3, CO2, CO, CH4, and particulate matter. Fires were observed from satellite imagery, and the smoke optical thickness, particle size, and profiles of the extinction coefficient were measured from the aircraft and from the ground. Four smoke plumes were sampled, three vertical profiles were measured, and extensive ground measurements of smoke optical characteristics were carried out for different smoke types. The simultaneous measurements of the trace gases, smoke particles, and the distribution of fires were used to correlate biomass burning with the elevated levels of ozone.
Land subsidence caused by ground water withdrawal in urban areas
Holzer, T.L.; Johnson, A.I.
1985-01-01
At least eight urban areas in the world have encountered significant economic impact from land subsidence caused by pumping of ground water from unconsolidated sediment. The areas, most of which are coastal, include Bangkok, Houston, Mexico City, Osaka, San Jose, Shanghai, Tokyo, and Venice. Flooding related to decreased ground elevation is the principal adverse effect of the subsidence. Lesser effects include regional tilting, well-casing failures, "rising" buildings, and ground failure or rupture. Subsidence of most of these urban areas began before the phenomenon was discovered and understood. Thus, the subsidence problems were unanticipated. Methods to arrest subsidence typically have included control of ground water pumping and development of surface water to offset the reductions of ground water pumping. Ground water recharge has also been practiced. Areas threatened by flooding have been protected by extensive networks of dikes and sea walls, locks, and pumping stations to remove storm runoff. ?? 1985 D. Reidel Publishing Company.
Dielectric Covered Planar Antennas
NASA Technical Reports Server (NTRS)
Llombart Juan, Nuria (Inventor); Lee, Choonsup (Inventor); Chattopadhyay, Goutam (Inventor); Gill, John J. (Inventor); Skalare, Anders J. (Inventor); Siegel, Peter H. (Inventor)
2014-01-01
An antenna element suitable for integrated arrays at terahertz frequencies is disclosed. The antenna element comprises an extended spherical (e.g. hemispherical) semiconductor lens, e.g. silicon, antenna fed by a leaky wave waveguide feed. The extended spherical lens comprises a substantially spherical lens adjacent a substantially planar lens extension. A couple of TE/TM leaky wave modes are excited in a resonant cavity formed between a ground plane and the substantially planar lens extension by a waveguide block coupled to the ground plane. Due to these modes, the primary feed radiates inside the lens with a directive pattern that illuminates a small sector of the lens. The antenna structure is compatible with known semiconductor fabrication technology and enables production of large format imaging arrays.
Multiple beacons for supporting lunar landing navigation
NASA Astrophysics Data System (ADS)
Theil, Stephan; Bora, Leonardo
2018-02-01
The exploration and potential future exploitation of solar system bodies requires technologies for precise and safe landings. Current navigation systems for landing probes are relying on a combination of inertial and optical sensor measurements to determine the current flight state with respect to the target body and the desired landing site. With a future transition from single exploration missions to more frequent first exploration and then exploitation missions, the implementation and operation of these missions changes, since it can be expected that a ground infrastructure on the target body is available in the vicinity of the landing site. In a previous paper, the impact of a single ground-based beacon on the navigation performance was investigated depending on the type of radiometric measurements and on the location of the beacon with respect to the landing site. This paper extends this investigation on options for ground-based multiple beacons supporting the on-board navigation system. It analyzes the impact on the achievable navigation accuracy. For that purpose, the paper introduces briefly the existing navigation architecture based on optical navigation and its extension with radiometric measurements. The same scenario of lunar landing as in the previous paper is simulated. The results are analyzed and discussed. They show a single beacon at a large distance along the landing trajectory and multiple beacons close to the landing site can improve the navigation performance. The results show how large the landing area can be increased where a sufficient navigation performance is achieved using the beacons.
New Ground-based Spectral Observations of Mercury and Comparison with the Moon
NASA Technical Reports Server (NTRS)
Blewett, D. T.; Warell, J.
2003-01-01
Spectroscopic observations (400-670 nm) of Mercury were made at La Palma with the Nordic Optical Telescope (NOT) in June and July of 2002. Extensive observations of solar analog standard stars and validation spectra of 7 Iris and a variety of locations on the Moon were also collected. The 2002 Mercury data were also combined with previous observations (520-970 nm) from the Swedish Solar Vacuum Telescope (SVST). A spectrum (400-970 nm) calibrated to standard bidirectional geometry (alpha=i=30deg, e=0deg) was constructed based on the spectral slopes from 2002. The combined spectrum permits analysis with the Lucey lunar abundance relations for FeO and TiO2.
Limitations to maximum running speed on flat curves.
Chang, Young-Hui; Kram, Rodger
2007-03-01
Why is maximal running speed reduced on curved paths? The leading explanation proposes that an increase in lateral ground reaction force necessitates a decrease in peak vertical ground reaction force, assuming that maximum leg extension force is the limiting factor. Yet, no studies have directly measured these forces or tested this critical assumption. We measured maximum sprint velocities and ground reaction forces for five male humans sprinting along a straight track and compared them to sprints along circular tracks of 1, 2, 3, 4 and 6 m radii. Circular track sprint trials were performed either with or without a tether that applied centripetal force to the center of mass. Sprinters generated significantly smaller peak resultant ground reaction forces during normal curve sprinting compared to straight sprinting. This provides direct evidence against the idea that maximum leg extension force is always achieved and is the limiting factor. Use of the tether increased sprint speed, but not to expected values. During curve sprinting, the inside leg consistently generated smaller peak forces compared to the outside leg. Several competing biomechanical constraints placed on the stance leg during curve sprinting likely make the inside leg particularly ineffective at generating the ground reaction forces necessary to attain maximum velocities comparable to straight path sprinting. The ability of quadrupeds to redistribute function across multiple stance legs and decouple these multiple constraints may provide a distinct advantage for turning performance.
A dynamic motion simulator for future European docking systems
NASA Technical Reports Server (NTRS)
Brondino, G.; Marchal, PH.; Grimbert, D.; Noirault, P.
1990-01-01
Europe's first confrontation with docking in space will require extensive testing to verify design and performance and to qualify hardware. For this purpose, a Docking Dynamics Test Facility (DDTF) was developed. It allows reproduction on the ground of the same impact loads and relative motion dynamics which would occur in space during docking. It uses a 9 degree of freedom, servo-motion system, controlled by a real time computer, which simulates the docking spacecraft in a zero-g environment. The test technique involves and active loop based on six axis force and torque detection, a mathematical simulation of individual spacecraft dynamics, and a 9 degree of freedom servomotion of which 3 DOFs allow extension of the kinematic range to 5 m. The configuration was checked out by closed loop tests involving spacecraft control models and real sensor hardware. The test facility at present has an extensive configuration that allows evaluation of both proximity control and docking systems. It provides a versatile tool to verify system design, hardware items and performance capabilities in the ongoing HERMES and COLUMBUS programs. The test system is described and its capabilities are summarized.
Plans of a test bed for ionospheric modelling based on Fennoscandian ground-based instrumentation
NASA Astrophysics Data System (ADS)
Kauristie, Kirsti; Kero, Antti; Verronen, Pekka T.; Aikio, Anita; Vierinen, Juha; Lehtinen, Markku; Turunen, Esa; Pulkkinen, Tuija; Virtanen, Ilkka; Norberg, Johannes; Vanhamäki, Heikki; Kallio, Esa; Kestilä, Antti; Partamies, Noora; Syrjäsuo, Mikko
2016-07-01
One of the recommendations for teaming among research groups in the COSPAR/ILWS roadmap is about building test beds in which coordinated observing supports model development. In the presentation we will describe a test bed initiative supporting research on ionosphere-thermosphere-magnetosphere interactions. The EISCAT incoherent scatter radars with their future extension, EISCAT3D, form the backbone of the proposed system. The EISCAT radars are surrounded by versatile and dense arrays of ground-based instrumentation: magnetometers and auroral cameras (the MIRACLE and IMAGE networks), ionospheric tomography receivers (the TomoScand network) and other novel technology for upper atmospheric probing with radio waves (e.g. the KAIRA facility, riometers and the ionosonde maintained by the Sodankylä Geophysical Observatory). As a new opening, close coordination with the Finnish national cubesat program is planned. We will investigate opportunities to establish a cost efficient nanosatellite program which would support the ground-based observations in a systematic and persistent manner. First experiences will be gathered with the Aalto-1 and Aalto-2 satellites, latter of which will be the Finnish contribution to the international QB50 mission. We envisage close collaboration also in the development of data analysis tools with the goal to integrate routines and models from different research groups to one system, where the different elements support each other. In the longer run we are aiming for a modelling framework with observational guidance which gives a holistic description on ionosphere-thermosphere processes and this way enables reliable forecasts on upper atmospheric space weather activity.
NASA Astrophysics Data System (ADS)
Garcia Menendez, F.; Afrin, S.
2017-12-01
Prescribed fires are used extensively across the Southeastern United States and are a major source of air pollutant emissions in the region. These land management projects can adversely impact local and regional air quality. However, the emissions and air pollution impacts of prescribed fires remain largely uncertain. Satellite data, commonly used to estimate fire emissions, is often unable to detect the low-intensity, short-lived prescribed fires characteristic of the region. Additionally, existing ground-based prescribed burn records are incomplete, inconsistent and scattered. Here we present a new unified database of prescribed fire occurrence and characteristics developed from systemized digital burn permit records collected from public and private land management organizations in the Southeast. This bottom-up fire database is used to analyze the correlation between high PM2.5 concentrations measured by monitoring networks in southern states and prescribed fire occurrence at varying spatial and temporal scales. We show significant associations between ground-based records of prescribed fire activity and the observational air quality record at numerous sites by applying regression analysis and controlling confounding effects of meteorology. Furthermore, we demonstrate that the response of measured PM2.5 concentrations to prescribed fire estimates based on burning permits is significantly stronger than their response to satellite fire observations from MODIS (moderate-resolution imaging spectroradiometer) and geostationary satellites or prescribed fire emissions data in the National Emissions Inventory. These results show the importance of bottom-up smoke emissions estimates and reflect the need for improved ground-based fire data to advance air quality impacts assessments focused on prescribed burning.
ERIC Educational Resources Information Center
Hachtmann, Frauke
2010-01-01
The purpose of this study was to develop a theory for institutional change that explains the process and implementation of "Achievement-Centered Education" (ACE) from the faculty perspective. ACE is a new general education program at the University of Nebraska-Lincoln, a public, doctoral/research-extensive institution. A constant…
4-H Youth Development: The Past, the Present, and the Future
ERIC Educational Resources Information Center
Borden, Lynne M.; Perkins, Daniel F.; Hawkey, Kyle
2014-01-01
The 4-H Program within Cooperative Extension is more than 100 years old. As we celebrate 100 years of Cooperative Extension, the foundation built by the 4-H Program serves as grounds to meet the needs of today's youth. The diversity of the youth who participate continues to grow, families continue to become less traditional, potential…
Study of Magnetic Damping Effect on Convection and Solidification Under G-Jitter Conditions
NASA Technical Reports Server (NTRS)
Li, Ben Q.; deGroh, H. C.
2001-01-01
As shown in space flight experiments, g-jitter is a critical issue affecting solidification processing of materials in microgravity. This study aims to provide, through extensive numerical simulations and ground based experiments, an assessment of the use of magnetic fields in combination with microgravity to reduce the g-jitter induced convective flows in space processing systems. Analytical solutions and 2-D and 3-D numerical models for g-jitter driven flows in simple solidification systems with and without the presence of an applied magnetic field have been developed and extensive analyses were carried out. A physical model was also constructed and PIV measurements compared reasonably well with predictions from numerical models. Some key points may be summarized as follows: (1) the amplitude of the oscillating velocity decreases at a rate inversely proportional to the g-jitter frequency and with an increase in the applied magnetic field; (2) the induced flow oscillates at approximately the same frequency as the affecting g-jitter, but out of a phase angle; (3) the phase angle is a complicated function of geometry, applied magnetic field, temperature gradient and frequency; (4) g-jitter driven flows exhibit a complex fluid flow pattern evolving in time; (5) the damping effect is more effective for low frequency flows; and (6) the applied magnetic field helps to reduce the variation of solutal distribution along the solid-liquid interface. Work in progress includes developing numerical models for solidification phenomena with the presence of both g-jitter and magnetic fields and developing a ground-based physical model to verify numerical predictions.
NASA Astrophysics Data System (ADS)
Sadrzadeh, M.; Langari, A.
2018-06-01
We study the effect of quantum fluctuations by means of a transverse magnetic field (Γ) on the highly degenerate ground state of antiferromagnetic J1 -J2 Ising model on the square lattice, at the limit J2 /J1 = 0.5 . We show that harmonic quantum fluctuations based on single spin flips can not lift such degeneracy, however an-harmonic quantum fluctuations based on multi spin cluster flip excitations lift the degeneracy toward a unique ground state with string-valence bond solid (VBS) nature. A cluster operator formalism has been implemented to incorporate an-harmonic quantum fluctuations. We show that cluster-type excitations of the model lead not only to lower the excitation energy compared with a single-spin flip but also to lift the extensive degeneracy in favor of a string-VBS state, which breaks lattice rotational symmetry with only two fold degeneracy. The tendency toward the broken symmetry state is justified by numerical exact diagonalization. Moreover, we introduce a map to find the relation between the present model on the checkerboard and square lattices.
Timing Comparisons for GLEs and High-energy Proton Events using GPS Proton Measurements
NASA Astrophysics Data System (ADS)
Bernstein, V.; Winter, L. M.; Carver, M.; Morley, S.
2017-12-01
The newly released LANL GPS particle sensor data offers a unique snapshot of access of relativistic particles into the geomagnetic field. Currently, 23 of the 31 operational GPS satellites host energetic particle detectors which can detect the arrival of high-energy solar protons associated with Ground Level Enhancements (GLEs). We compare the timing profiles of solar energetic proton detections from GPS satellites as well as from ground-based Neutron Monitors and GOES spacecraft at geostationary orbit in order to understand how high-energy protons from the Sun enter the geomagnetic field and investigate potential differences in arrival time of energetic protons at GPS satellites as a function of location. Previous studies could only use one or two spacecraft at a similar altitude to track the arrival of energetic particles. With GPS data, we can now test whether the particles arrive isotropically, as assumed, or whether there exist differences in the timing and energetics viewed by each of the individual satellites. Extensions of this work could lead to improvements in space weather forecasting that predict more localized risk estimates for space-based technology.
NASA Technical Reports Server (NTRS)
Zhou, Daniel K.; Smith, William L.; Bingham, Gail E.; Huppi, Ronald J.; Revercomb, Henry E.; Zollinger, Lori J.; Larar, Allen M.; Liu, Xu; Tansock, Joseph J.; Reisse, Robert A.;
2007-01-01
The geosynchronous-imaging Fourier transform spectrometer (GIFTS) engineering demonstration unit (EDU) is an imaging infrared spectrometer designed for atmospheric soundings. It measures the infrared spectrum in two spectral bands (14.6 to 8.8 microns, 6.0 to 4.4 microns) using two 128 x 128 detector arrays with a spectral resolution of 0.57 cm(exp -1) with a scan duration of approximately 11 seconds. From a geosynchronous orbit, the instrument will have the capability of taking successive measurements of such data to scan desired regions of the globe, from which atmospheric status, cloud parameters, wind field profiles, and other derived products can be retrieved. The GIFTS EDU provides a flexible and accurate testbed for the new challenges of the emerging hyperspectral era. The EDU ground-based measurement experiment, held in Logan, Utah during September 2006, demonstrated its extensive capabilities and potential for geosynchronous and other applications (e.g., Earth observing environmental measurements). This paper addresses the experiment objectives and overall performance of the sensor system with a focus on the GIFTS EDU imaging capability and proof of the GIFTS measurement concept.
Comparison of thyroid segmentation techniques for 3D ultrasound
NASA Astrophysics Data System (ADS)
Wunderling, T.; Golla, B.; Poudel, P.; Arens, C.; Friebe, M.; Hansen, C.
2017-02-01
The segmentation of the thyroid in ultrasound images is a field of active research. The thyroid is a gland of the endocrine system and regulates several body functions. Measuring the volume of the thyroid is regular practice of diagnosing pathological changes. In this work, we compare three approaches for semi-automatic thyroid segmentation in freehand-tracked three-dimensional ultrasound images. The approaches are based on level set, graph cut and feature classification. For validation, sixteen 3D ultrasound records were created with ground truth segmentations, which we make publicly available. The properties analyzed are the Dice coefficient when compared against the ground truth reference and the effort of required interaction. Our results show that in terms of Dice coefficient, all algorithms perform similarly. For interaction, however, each algorithm has advantages over the other. The graph cut-based approach gives the practitioner direct influence on the final segmentation. Level set and feature classifier require less interaction, but offer less control over the result. All three compared methods show promising results for future work and provide several possible extensions.
Self-assembly of colloids with magnetic caps
NASA Astrophysics Data System (ADS)
Novak, E. V.; Kantorovich, S. S.
2017-06-01
In our earlier work (Steinbach et al., 2016 [1]) we investigated a homogeneous system of magnetically capped colloidal particles that self-assembled via two structural patterns of different symmetry. The particles could form a compact, equilateral triangle with a three-fold rotational symmetry and zero dipole moment and a staggered chain with mirror symmetry with a net magnetisation perpendicular to the chain. The system exhibited a bistability already in clusters of three particles. Based on observations of a real magnetic particles system, analytical calculations and molecular dynamics simulations, it has been shown that the bistability is a result of an anisotropic magnetisation distribution with rotational symmetry inside the particles. The present study is a logical extension of the above research and forms a preparatory stage for the study of a self-assembly of such magnetic particles under the influence of an external magnetic field. Since the magnetic field is only an additive contribution to the total ground state energy, we can study the interparticle interaction energies of candidate ground state structures based on the field-free terms.
LLNL electro-optical mine detection program
DOE Office of Scientific and Technical Information (OSTI.GOV)
Anderson, C.; Aimonetti, W.; Barth, M.
1994-09-30
Under funding from the Advanced Research Projects Agency (ARPA) and the US Marine Corps (USMC), Lawrence Livermore National Laboratory (LLNL) has directed a program aimed at improving detection capabilities against buried mines and munitions. The program has provided a national test facility for buried mines in arid environments, compiled and distributed an extensive data base of infrared (IR), ground penetrating radar (GPR), and other measurements made at that site, served as a host for other organizations wishing to make measurements, made considerable progress in the use of ground penetrating radar for mine detection, and worked on the difficult problem ofmore » sensor fusion as applied to buried mine detection. While the majority of our effort has been concentrated on the buried mine problem, LLNL has worked with the U.S.M.C. on surface mine problems as well, providing data and analysis to support the COBRA (Coastal Battlefield Reconnaissance and Analysis) program. The original aim of the experimental aspect of the program was the utilization of multiband infrared approaches for the detection of buried mines. Later the work was extended to a multisensor investigation, including sensors other than infrared imagers. After an early series of measurements, it was determined that further progress would require a larger test facility in a natural environment, so the Buried Object Test Facility (BOTF) was constructed at the Nevada Test Site. After extensive testing, with sensors spanning the electromagnetic spectrum from the near ultraviolet to radio frequencies, possible paths for improvement were: improved spatial resolution providing better ground texture discrimination; analysis which involves more complicated spatial queueing and filtering; additional IR bands using imaging spectroscopy; the use of additional sensors other than IR and the use of data fusion techniques with multi-sensor data; and utilizing time dependent observables like temperature.« less
Enabling Air Force Satellite Ground System Automation Through Software Engineering
US Air Force satellite ground stations require significant manpower to operate due to their fragmented legacy architectures . To improve operating...daily operations, but also the development, maintainability, and the extensibility of such systems. This thesis researches challenges to Air Force...satellite automation: 1) existing architecture of legacy systems, 2) space segment diversity, and 3) unclear definition and scoping of the term, automation
Remote Attitude Measurement Sensor (RAMS)
NASA Technical Reports Server (NTRS)
Davis, H. W.
1989-01-01
Remote attitude measurement sensor (RAMS) offers a low-cost, low-risk, proven design concept that is based on mature, demonstrated space sensor technology. The electronic design concepts and interpolation algorithms were tested and proven in space hardware like th Retroreflector Field Tracker and various star trackers. The RAMS concept is versatile and has broad applicability to both ground testing and spacecraft needs. It is ideal for use as a precision laboratory sensor for structural dynamics testing. It requires very little set-up or preparation time and the output data is immediately usable without integration or extensive analysis efforts. For on-orbit use, RAMS rivals any other type of dynamic structural sensor (accelerometer, lidar, photogrammetric techniques, etc.) for overall performance, reliability, suitability, and cost. Widespread acceptance and extensive usage of RAMS will occur only after some interested agency, such as OAST, adopts the RAMS concept and provides the funding support necessary for further development and implementation of RAMS for a specific program.
NASA/ESA CV-990 spacelab simulation
NASA Technical Reports Server (NTRS)
1975-01-01
Due to interest in the application of simplified techniques used to conduct airborne science missions at NASA's Ames Research Center, a joint NASA/ESA endeavor was established to conduct an extensive Spacelab simulation using the NASA CV-990 airborne laboratory. The scientific payload was selected to perform studies in upper atmospheric physics and infrared astronomy with principal investigators from France, the Netherlands, England, and several groups from the United States. Communication links between the 'Spacelab' and a ground based mission operations center were limited consistent with Spacelab plans. The mission was successful and provided extensive data relevant to Spacelab objectives on overall management of a complex international payload; experiment preparation, testing, and integration; training for proxy operation in space; data handling; multiexperimenter use of common experimenter facilities (telescopes); multiexperiment operation by experiment operators; selection criteria for Spacelab experiment operators; and schedule requirements to prepare for such a Spacelab mission.
Müller, Rolf; Kunz, Anne; Hurst, Dale F; Rolf, Christian; Krämer, Martina; Riese, Martin
2016-02-01
Water vapor is the most important greenhouse gas in the atmosphere although changes in carbon dioxide constitute the "control knob" for surface temperatures. While the latter fact is well recognized, resulting in extensive space-borne and ground-based measurement programs for carbon dioxide as detailed in the studies by Keeling et al. (1996), Kuze et al. (2009), and Liu et al. (2014), the need for an accurate characterization of the long-term changes in upper tropospheric and lower stratospheric (UTLS) water vapor has not yet resulted in sufficiently extensive long-term international measurement programs (although first steps have been taken). Here, we argue for the implementation of a long-term balloon-borne measurement program for UTLS water vapor covering the entire globe that will likely have to be sustained for hundreds of years.
Structural impact response for assessing railway vibration induced on buildings
NASA Astrophysics Data System (ADS)
Kouroussis, Georges; Mouzakis, Harris P.; Vogiatzis, Konstantinos E.
2018-03-01
Over the syears, the rapid growth in railway infrastructure has led to numerous environmental challenges. One such significant issue, particularly in urban areas, is ground-borne vibration. A common source of ground-borne vibration is caused by local defects (e.g. rail joints, switches, turnouts, etc.) that generate large amplitude excitations at isolated locations. Modelling these excitation sources is particularly challenging and requires the use of complex and extensive computational efforts. For some situations, the use of experiments and measured data offers a rapid way to estimate the effect of such defects and to evaluate the railway vibration levels using a scoping approach. In this paper, the problem of railway-induced ground vibrations is presented along with experimental studies to assess the ground vibration and ground borne noise levels, with a particular focus on the structural response of sensitive buildings. The behaviour of particular building foundations is evaluated through experimental data collected in Brussels Region, by presenting the expected frequency responses for various types of buildings, taking into account both the soil-structure interaction and the tramway track response. A second study is dedicated to the Athens metro, where transmissibility functions are used to analyse the effect of various Athenian building face to metro network trough comprehensive measurement campaigns. This allows the verification of appropriate vibration mitigation measures. These benchmark applications based on experimental results have been proved to be efficient to treat a complex problem encountered in practice in urban areas, where the urban rail network interacts with important local defects and where the rise of railway ground vibration problems has clearly been identified.
Geo-information for sustainable urban development of Greater Dhaka City, Bangladesh
NASA Astrophysics Data System (ADS)
Günther, Andreas; Asaduzzaman, Atm; Bahls, Rebecca; Ludwig, Rüdiger; Ashraful Kamal, Mohammad; Nahar Faruqa, Nurun
2015-04-01
Greater Dhaka City (including Dhaka and five adjacent municipal areas) is one of the fastest developing urban regions in the world. Densely build-up areas in the developed metropolitan area of Dhaka City are subject to extensive restructuring as common six-storied buildings are replaced by higher and heavier constructions. Additional stories are built on existing houses, frequently exceeding the allowable bearing pressure on the subsoil as supported by the foundations. In turn, newly developing areas are projected in marshy areas modified by extensive, largely unengineered landfills. In many areas, these terrains bear unfavorable building ground conditions, and reliable geospatial information is a major prerequisite for risk-sensitive urban planning. Within a collaborative technical cooperation project between Bangladesh and Germany, BGR supports GSB in the provision of geo-information for the Capital Development authority (RAJUK). For general urban planning, RAJUK successively develops a detailed area plan (DAP) at scale 1 : 50000 for the whole Greater Dhaka City area. Geospatial information have not been considered in the present DAP. Within the project, GSB prepared a detailed geomorphologic map matching the DAP both in areal extent and scale. The geomorphological setting can be used as an important spatial proxy for the characterization of the subsurface since highly segmented, elevated terraces consisting of consolidated sandy Pliocene deposits overlain by stiff Plio-Pleistocene sediments are sharply bordered by low lying-areas. The floodplain and marsh areas are consisting of thick, mechanically weak Holocene fluvial sandy-silty sediments that are sometimes alternated by organic layers. A first expert-based engineering geological reclassification of the geomorphological map resulting in five building ground suitability classes is highly supported by the spatial analysis of extensive archive borehole information consisting of depth-continuous standard penetration test (SPT) observations, engineering geological sample analyses and lithological profiles. The database compiled within the project currently contains more than 1600 locations. The joining of the spatial geomorphological information with the borehole data allows a specific characterization of the building ground classes in terms of bearing capacities for different foundation designs, earthquake-induced subsoil liquefaction potentials and depth-to-engineering rock head considerations. First-order hazard and cost scenarios for several general types of projected settlements can already be broadly evaluated with the data presented in a small scale (DAP scale). However, detailed building ground surveys have to be performed at larger spatial scales (1 : 10000 - 1 : 5000) in areas assigned for new settlements. These involve regular spaced borehole observations, 3-D modeling of the subsurface and geophysical loggings. Within the project, specific representative pilot areas in different geomorphological settings are defined where detailed geospatial building ground investigations are conducted, providing a robust basis for sustainable urban planning related to natural and technological hazards and their associated risks.
NASA Astrophysics Data System (ADS)
Jayanthi, Harikishan
The focus of this research was two-fold: (1) extend the reflectance-based crop coefficient approach to non-grain (potato and sugar beet), and vegetable crops (bean), and (2) develop vegetation index (VI)-yield statistical models for potato and sugar beet crops using high-resolution aerial multispectral imagery. Extensive crop biophysical sampling (leaf area index and aboveground dry biomass sampling) and canopy reflectance measurements formed the backbone of developing of canopy reflectance-based crop coefficients for bean, potato, and sugar beet crops in this study. Reflectance-based crop coefficient equations were developed for the study crops cultivated in Kimberly, Idaho, and subsequently used in water availability simulations in the plant root zone during 1998 and 1999 seasons. The simulated soil water profiles were compared with independent measurements of actual soil water profiles in the crop root zone in selected fields. It is concluded that the canopy reflectance-based crop coefficient technique can be successfully extended to non-grain crops as well. While the traditional basal crop coefficients generally expect uniform growth in a region the reflectance-based crop coefficients represent the actual crop growth pattern (in less than ideal water availability conditions) in individual fields. Literature on crop canopy interactions with sunlight states that there is a definite correspondence between leaf area index progression in the season and the final yield. In case of crops like potato and sugar beet, the yield is influenced not only on how early and how quickly the crop establishes its canopy but also on how long the plant stands on the ground in a healthy state. The integrated area under the crop growth curve has shown excellent correlations with hand-dug samples of potato and sugar beet crops in this research. Soil adjusted vegetation index-yield models were developed, and validated using multispectral aerial imagery. Estimated yield images were compared with the actual yields extracted from the ground. The remote sensing-derived yields compared well with the actual yields sampled on the ground. This research has highlighted the importance of the date of spectral emergence, the need to know the duration for which the crops stand on the ground, and the need to identify critical periods of time when multispectral coverages are essential for reliable tuber yield estimation.
Stonestrom, David A.; Prudic, David E.; Walvoord, Michelle Ann; Abraham, Jared D.; Stewart-Deaker, Amy E.; Glancy, Patrick A.; Constantz, Jim; Laczniak, Randell J.; Andraski, Brian J.; Stonestrom, David A.; Constantz, Jim; Ferré, Ty P.A.; Leake, Stanley A.
2007-01-01
The Amargosa River is an approximately 300-kilometer long regional drainage connecting the northern highlands on the Nevada Test Site in Nye County, Nev., to the floor of Death Valley in Inyo County, Calif. Streamflow analysis indicates that the Amargosa Desert portion of the river is dry more than 98 percent of the time. Infiltration losses during ephemeral flows of the Amargosa River and Fortymile Wash provide the main sources of ground-water recharge on the desert-basin floor. The primary use of ground water is for irrigated agriculture. The current study examined ground-water recharge from ephemeral flows in the Amargosa River by using streamflow data and environmental tracers. The USGS streamflow-gaging station at Beatty, Nev., provided high-frequency data on base flow and storm runoff entering the basin during water years 1998–2001. Discharge into the basin during the four-year period totaled 3.03 million cubic meters, three quarters of which was base flow. Streambed temperature anomalies indicated the distribution of ephemeral flows and infiltration losses within the basin. Major storms that produced regional flow during the four-year period occurred in February 1998, during a strong El Niño that more than doubled annual precipitation, and in July 1999. The study also quantified recharge beneath undisturbed native vegetation and irrigation return flow beneath irrigated fields. Vertical profiles of water potential and environmental tracers in the unsaturated zone provided estimates of recharge beneath the river channel (0.04–0.09 meter per year) and irrigated fields (0.1–0.5 meter per year). Chloride mass-balance estimates indicate that 12–15 percent of channel infiltration becomes ground-water recharge, together with 9–22 percent of infiltrated irrigation. Profiles of potential and chloride beneath the dominant desert-shrub vegetation suggest that ground-water recharge has been negligible throughout most of the basin since at least the early Holocene. Surface-based electrical-resistivity imaging provided areal extension of borehole information from sampled profiles. These images indicate narrowly focused recharge beneath the Amargosa River channel, flanked by large tracts of recharge-free basin floor.
NASA Technical Reports Server (NTRS)
Shaffer, Scott; Dunbar, R. Scott; Hsiao, S. Vincent; Long, David G.
1989-01-01
The NASA Scatterometer, NSCAT, is an active spaceborne radar designed to measure the normalized radar backscatter coefficient (sigma0) of the ocean surface. These measurements can, in turn, be used to infer the surface vector wind over the ocean using a geophysical model function. Several ambiguous wind vectors result because of the nature of the model function. A median-filter-based ambiguity removal algorithm will be used by the NSCAT ground data processor to select the best wind vector from the set of ambiguous wind vectors. This process is commonly known as dealiasing or ambiguity removal. The baseline NSCAT ambiguity removal algorithm and the method used to select the set of optimum parameter values are described. An extensive simulation of the NSCAT instrument and ground data processor provides a means of testing the resulting tuned algorithm. This simulation generates the ambiguous wind-field vectors expected from the instrument as it orbits over a set of realistic meoscale wind fields. The ambiguous wind field is then dealiased using the median-based ambiguity removal algorithm. Performance is measured by comparison of the unambiguous wind fields with the true wind fields. Results have shown that the median-filter-based ambiguity removal algorithm satisfies NSCAT mission requirements.
NASA Astrophysics Data System (ADS)
Ichii, T.; Nishikawa, H.; Igarashi, H.; Okamura, H.; Mahapatra, K.; Sakai, M.; Wakabayashi, T.; Inagake, D.; Okada, Y.
2017-01-01
We investigated the impacts of extensive anthropogenic (high seas driftnet squid fishery) and natural (late 1990s major climate regime shift) events on dominant epipelagic fish, squid, and shark in the central North Pacific Transition Region based on a driftnet survey covering the years 1979-2006. Fishing was conducted by Japan, Korea and Taiwan to target neon flying squid in the period 1979-1992, resulting in a decline in stocks of the target species and non-target species (Pacific pomfret and juvenile blue shark), which were by-catch of this fishery. The catch was found to be at the maximum sustainable yield (MSY) level for neon flying squid, the underfished level for juvenile blue shark, but the overfished level for Pacific pomfret. The MSY of Pacific pomfret indicated that this species is more susceptible to exploitation than previously considered. In response to the late 1990s regime shift, neon flying squid and Pacific saury showed low stock levels in 1999-2002 and 1998-2002, respectively, as a result of reduced productivity in their nursery grounds (the Subtropical Frontal Zone and Kuroshio Extension Bifurcation Region, respectively). On the other hand, Pacific pomfret showed no decreasing trend in stock during the low- and intermediate-productivity regimes because of the high productivity of their main spawning/nursery ground (Transition Zone Chlorophyll Front), which was independent of the regime shifts. Thus, squid and saury appear to be more susceptible to the regime shift than pomfret. We discuss the implications for stock management of the species-specific responses to the fishery and the regime shift.
Kepler and Ground-Based Transits of the exo-Neptune HAT-P-11b
NASA Technical Reports Server (NTRS)
Deming, Drake; Sada, Pedro V.; Jackson, Brian; Peterson, Steven W.; Agol, Eric; Knutson, Heather A.; Jennings, Donald E.; Haase, Plynn; Bays, Kevin
2011-01-01
We analyze 26 archival Kepler transits of the exo-Neptune HAT-P-11b, supplemented by ground-based transits observed in the blue (B band) and near-IR (J band). Both the planet and host star are smaller than previously believed; our analysis yields Rp = 4.31 R xor 0.06 R xor and Rs = 0.683 R solar mass 0.009 R solar mass, both about 3 sigma smaller than the discovery values. Our ground-based transit data at wavelengths bracketing the Kepler bandpass serve to check the wavelength dependence of stellar limb darkening, and the J-band transit provides a precise and independent constraint on the transit duration. Both the limb darkening and transit duration from our ground-based data are consistent with the new Kepler values for the system parameters. Our smaller radius for the planet implies that its gaseous envelope can be less extensive than previously believed, being very similar to the H-He envelope of GJ 436b and Kepler-4b. HAT-P-11 is an active star, and signatures of star spot crossings are ubiquitous in the Kepler transit data. We develop and apply a methodology to correct the planetary radius for the presence of both crossed and uncrossed star spots. Star spot crossings are concentrated at phases 0.002 and +0.006. This is consistent with inferences from Rossiter-McLaughlin measurements that the planet transits nearly perpendicular to the stellar equator. We identify the dominant phases of star spot crossings with active latitudes on the star, and infer that the stellar rotational pole is inclined at about 12 deg 5 deg to the plane of the sky. We point out that precise transit measurements over long durations could in principle allow us to construct a stellar Butterfly diagram to probe the cyclic evolution of magnetic activity on this active K-dwarf star.
Bi-Component Droplet Combustion in Reduced Gravity
NASA Technical Reports Server (NTRS)
Shaw, Benjamin D.
2004-01-01
This research deals with reduced-gravity combustion of bi-component droplets initially in the mm size range or larger. The primary objectives of the research are to study the effects of droplet internal flows, thermal and solutal Marangoni stresses, and species volatility differences on liquid species transport and overall combustion phenomena (e.g., gas-phase unsteadiness, burning rates, sooting, radiation, and extinction). The research program utilizes a reduced gravity environment so that buoyancy effects are rendered negligible. Use of large droplets also facilitates visualization of droplet internal flows, which is important for this research. In the experiments, droplets composed of low- and high-volatility species are burned. The low-volatility components are initially present in small amounts. As combustion of a droplet proceeds, the liquid surface mass fraction of the low-volatility component will increase with time, resulting in a sudden and temporary decrease in droplet burning rates as the droplet rapidly heats to temperatures close to the boiling point of the low-volatility component. This decrease in burning rates causes a sudden and temporary contraction of the flame. The decrease in burning rates and the flame contraction can be observed experimentally. Measurements of burning rates as well as the onset time for flame contraction allow effective liquid-phase species diffusivities to be calculated, e.g., using asymptotic theory. It is planned that droplet internal flows will be visualized in flight and ground-based experiments. In this way, effective liquid species diffusivities can be related to droplet internal flow characteristics. This program is a continuation of extensive ground-based experimental and theoretical research on bi-component droplet combustion that has been ongoing for several years. The focal point of this program is a flight experiment (Bi-Component Droplet Combustion Experiment, BCDCE). This flight experiment is under development. However, supporting ground-based studies have been performed. Some of the most recent ground-based research is summarized.
Aquifer recharge from infiltration basins in a highly urbanized area: the river Po Plain (Italy)
NASA Astrophysics Data System (ADS)
Masetti, M.; Nghiem, S. V.; Sorichetta, A.; Stevenazzi, S.; Santi, E. S.; Pettinato, S.; Bonfanti, M.; Pedretti, D.
2015-12-01
Due to the extensive urbanization in the Po Plain in northern Italy, rivers need to be managed to alleviate flooding problems while maintaining an appropriate aquifer recharge under an increasing percentage of impermeable surfaces. During the PO PLain Experiment field campaign in July 2015 (POPLEX 2015), both active and under-construction infiltration basins have been surveyed and analyzed to identify appropriate satellite observations that can be integrated to ground based monitoring techniques. A key strategy is to have continuous data time series on water presence and level within the basin, for which ground based monitoring can be costly and difficult to be obtained consistently.One of the major and old infiltration basin in the central Po Plain has been considered as pilot area. The basin is active from 2003 with ground based monitoring available since 2009 and supporting the development of a calibrated unsaturated-saturated two-dimensional numerical model simulating the infiltration dynamics through the basin.A procedure to use satellite data to detect surface water change is under development based on satellite radar backscatter data with an appropriate incidence angle and polarization combination. An advantage of satellite radar is that it can observe surface water regardless of cloud cover, which can be persistent during rainy seasons. Then, the surface water change is correlated to the reservoir water stage to determine water storage in the basin together with integrated ground data and to give quantitative estimates of variations in the local water cycle.We evaluated the evolution of the infiltration rate, to obtain useful insights about the general recharge behavior of basins that can be used for informed design and maintenance. Results clearly show when the basin becomes progressively clogged by biofilms that can reduce the infiltration capacity of the basin by as much as 50 times compared to when it properly works under clean conditions.
Investigation on contribution of neutron monitor data to estimation of aviation doses.
Kákona, M; Ploc, O; Kyselová, D; Kubančák, J; Langer, R; Kudela, K
2016-11-01
Recently, many efforts have appeared to routinely measure radiation exposure (RE) of aircraft crew due to cosmic rays (CR). On the other hand real-time CR data measured with the ground based neutron monitors (NMs) are collected worldwide and available online. This is an opportunity for comparison of long-term observations of RE at altitudes of about 10km, where composition and energy spectra of secondary particles differ from those on the ground, with the data from NMs. Our contribution presents examples of such type of comparison. Analysis of the silicon spectrometer Liulin measurements aboard aircraft is presented over the period May-September 2005 and compared with data from a single NM at middle latitude. While extreme solar driven events observed by NMs have clearly shown an impact on dosimetric characteristics as measured on the airplanes, the transient short time effects in CR of smaller amplitude have been not studied extensively in relation to RE. For the period May-September 2005, when aircraft data become available and several Forbush decreases (FDs) are observed on the ground, a small improvement in the correlation between the dose measured and multiple linear regression fit based on two key parameters (altitude and geomagnetic cut-off rigidity), is obtained, if the CR intensity at a single NM is added into the scheme. Copyright © 2016 The Committee on Space Research (COSPAR). Published by Elsevier Ltd. All rights reserved.
Validation of an Innovative Satellite-Based UV Dosimeter
NASA Astrophysics Data System (ADS)
Morelli, Marco; Masini, Andrea; Simeone, Emilio; Khazova, Marina
2016-08-01
We present an innovative satellite-based UV (ultraviolet) radiation dosimeter with a mobile app interface that has been validated by exploiting both ground-based measurements and an in-vivo assessment of the erythemal effects on some volunteers having a controlled exposure to solar radiation.Both validations showed that the satellite-based UV dosimeter has a good accuracy and reliability needed for health-related applications.The app with this satellite-based UV dosimeter also includes other related functionalities such as the provision of safe sun exposure time updated in real-time and end exposure visual/sound alert. This app will be launched on the global market by siHealth Ltd in May 2016 under the name of "HappySun" and available both for Android and for iOS devices (more info on http://www.happysun.co.uk).Extensive R&D activities are on-going for further improvement of the satellite-based UV dosimeter's accuracy.
Extension of the Kohn-Sham formulation of density functional theory to finite temperature
Gonis, A.; Dane, M.
2017-12-20
Based on Mermin's extension of the Hohenberg and Kohn theorems to non-zero temperature, the Kohn-Sham formulation of density functional theory (KS-DFT) is generalized to finite temperature. Here, we show that present formulations are inconsistent with Mermin's functional containing expressions, in particular describing the Coulomb energy, that defy derivation and are even in violation of rules of logical inference. More; current methodology is in violation of fundamental laws of both quantum and classical mechanics. Based on this feature, we demonstrate the impossibility of extending the KS formalism to finite temperature through the self-consistent solutions of the single-particle Schrödinger equation of T>0.more » Guided by the form of Mermin's functional that depends on the eigenstates of a Hamiltonian, determined at T>0 we base our extension of KS-DFT on the determination of the excited states of a non-interacting system at the zero of temperature. The resulting formulation is consistent with that of Mermin constructing the free energy at T>0 in terms of the excited states of a non-interacting Hamiltonian (system) that, within the KS formalism, are described by Slater determinants. To determine the excited states at T=0 use is made of the extension of the Hohenberg and Kohn theorems to excited states presented in previous work applied here to a non-interacting collection of replicas of a non-interacting N-particle system, whose ground state density is taken to match that of K non-interacting replicas of an interacting N-particle system at T>0. The formalism allows for an ever denser population of the excitation spectrum of a Hamiltonian, within the KS approximation. The form of the auxiliary potential, (Kohn-Sham potential), is formally identical to that in the ground state formalism with the contribution of the Coulomb energy provided by the derivative of the Coulomb energy in all excited states taken into account. Once the excited states are determined, the minimum of the free energy within the KS formalism follows immediately in the form of Mermin's functional, but with the exact excited states in that functional represented by Slater determinants obtained through self-consistency conditions at the zero of temperature. Lastly, it is emphasized that, in departure from all existing formulations, no self-consistency conditions are implemented at finite T; as we show, in fact, such formulations are rigorously blocked.« less
Extension of the Kohn-Sham formulation of density functional theory to finite temperature
DOE Office of Scientific and Technical Information (OSTI.GOV)
Gonis, A.; Dane, M.
Based on Mermin's extension of the Hohenberg and Kohn theorems to non-zero temperature, the Kohn-Sham formulation of density functional theory (KS-DFT) is generalized to finite temperature. Here, we show that present formulations are inconsistent with Mermin's functional containing expressions, in particular describing the Coulomb energy, that defy derivation and are even in violation of rules of logical inference. More; current methodology is in violation of fundamental laws of both quantum and classical mechanics. Based on this feature, we demonstrate the impossibility of extending the KS formalism to finite temperature through the self-consistent solutions of the single-particle Schrödinger equation of T>0.more » Guided by the form of Mermin's functional that depends on the eigenstates of a Hamiltonian, determined at T>0 we base our extension of KS-DFT on the determination of the excited states of a non-interacting system at the zero of temperature. The resulting formulation is consistent with that of Mermin constructing the free energy at T>0 in terms of the excited states of a non-interacting Hamiltonian (system) that, within the KS formalism, are described by Slater determinants. To determine the excited states at T=0 use is made of the extension of the Hohenberg and Kohn theorems to excited states presented in previous work applied here to a non-interacting collection of replicas of a non-interacting N-particle system, whose ground state density is taken to match that of K non-interacting replicas of an interacting N-particle system at T>0. The formalism allows for an ever denser population of the excitation spectrum of a Hamiltonian, within the KS approximation. The form of the auxiliary potential, (Kohn-Sham potential), is formally identical to that in the ground state formalism with the contribution of the Coulomb energy provided by the derivative of the Coulomb energy in all excited states taken into account. Once the excited states are determined, the minimum of the free energy within the KS formalism follows immediately in the form of Mermin's functional, but with the exact excited states in that functional represented by Slater determinants obtained through self-consistency conditions at the zero of temperature. Lastly, it is emphasized that, in departure from all existing formulations, no self-consistency conditions are implemented at finite T; as we show, in fact, such formulations are rigorously blocked.« less
Ab initio Bogoliubov coupled cluster theory for open-shell nuclei
Signoracci, Angelo J.; Duguet, Thomas; Hagen, Gaute; ...
2015-06-29
Background: Ab initio many-body methods have been developed over the past 10 yr to address closed-shell nuclei up to mass A≈130 on the basis of realistic two- and three-nucleon interactions. A current frontier relates to the extension of those many-body methods to the description of open-shell nuclei. Several routes to address open-shell nuclei are currently under investigation, including ideas that exploit spontaneous symmetry breaking. Purpose: Singly open-shell nuclei can be efficiently described via the sole breaking of U(1) gauge symmetry associated with particle-number conservation as a way to account for their superfluid character. While this route was recently followed withinmore » the framework of self-consistent Green's function theory, the goal of the present work is to formulate a similar extension within the framework of coupled cluster theory. Methods: We formulate and apply Bogoliubov coupled cluster (BCC) theory, which consists of representing the exact ground-state wave function of the system as the exponential of a quasiparticle excitation cluster operator acting on a Bogoliubov reference state. Equations for the ground-state energy and the cluster amplitudes are derived at the singles and doubles level (BCCSD) both algebraically and diagrammatically. The formalism includes three-nucleon forces at the normal-ordered two-body level. The first BCC code is implemented in m scheme, which will permit the treatment of doubly open-shell nuclei via the further breaking of SU(2) symmetry associated with angular momentum conservation. Results: Proof-of-principle calculations in an N max=6 spherical harmonic oscillator basis for 16,18O and 18Ne in the BCCD approximation are in good agreement with standard coupled cluster results with the same chiral two-nucleon interaction, while 20O and 20Mg display underbinding relative to experiment. The breaking of U(1) symmetry, monitored by computing the variance associated with the particle-number operator, is relatively constant for all five nuclei, in both the Hartree-Fock-Bogoliubov and BCCD approximations. Conclusions: The newly developed many-body formalism increases the potential span of ab initio calculations based on single-reference coupled cluster techniques tremendously, i.e., potentially to reach several hundred additional midmass nuclei. The new formalism offers a wealth of potential applications and further extensions dedicated to the description of ground and excited states of open-shell nuclei. Short-term goals include the implementation of three-nucleon forces at the normal-ordered two-body level. Midterm extensions include the approximate treatment of triples corrections and the development of the equation-of-motion methodology to treat both excited states and odd nuclei. Long-term extensions include exact restoration of U(1) and SU(2) symmetries.« less
The Tracking Meteogram, an AWIPS II Tool for Time-Series Analysis
NASA Technical Reports Server (NTRS)
Burks, Jason Eric; Sperow, Ken
2015-01-01
A new tool has been developed for the National Weather Service (NWS) Advanced Weather Interactive Processing System (AWIPS) II through collaboration between NASA's Short-term Prediction Research and Transition (SPoRT) and the NWS Meteorological Development Laboratory (MDL). Referred to as the "Tracking Meteogram", the tool aids NWS forecasters in assessing meteorological parameters associated with moving phenomena. The tool aids forecasters in severe weather situations by providing valuable satellite and radar derived trends such as cloud top cooling rates, radial velocity couplets, reflectivity, and information from ground-based lightning networks. The Tracking Meteogram tool also aids in synoptic and mesoscale analysis by tracking parameters such as the deepening of surface low pressure systems, changes in surface or upper air temperature, and other properties. The tool provides a valuable new functionality and demonstrates the flexibility and extensibility of the NWS AWIPS II architecture. In 2014, the operational impact of the tool was formally evaluated through participation in the NOAA/NWS Operations Proving Ground (OPG), a risk reduction activity to assess performance and operational impact of new forecasting concepts, tools, and applications. Performance of the Tracking Meteogram Tool during the OPG assessment confirmed that it will be a valuable asset to the operational forecasters. This presentation reviews development of the Tracking Meteogram tool, performance and feedback acquired during the OPG activity, and future goals for continued support and extension to other application areas.
Correlative measurements of the stratospheric aerosols
NASA Astrophysics Data System (ADS)
Santer, R.; Brogniez, C.; Herman, M.; Diallo, S.; Ackerman, M.
1992-12-01
Joint experiments were organized or available during stratospheric flights of a photopolarimeter, referred to as RADIBAL (radiometer balloon). In May 1984, RADIBAL flew simultaneously with another balloonborne experiment conducted by the Institut d'Aeronomie Spatiale de Belgique (IASB), which provides multiwavelength vertical profiles of the aerosol scattering coefficient. At this time, the El Chichon layer was observable quite directly from mountain sites. A ground-based station set up at Pic du Midi allowed an extensive description of the aerosol optical properties. The IASB and the Pic du Midi observations are consistent with the aerosol properties derived from the RADIBAL measurement analysis.
NASA Astrophysics Data System (ADS)
Elshoukrofy, A. Sh. M.; Postnikov, E. B.; Korosteleva, E. E.; Sveshnikova, L. G.; Motaweh, H. A.
2017-06-01
In this paper we propose a `knee-like' approximation of the lateral distribution of the Cherenkov light from extensive air showers in the energy range 30-3000 TeV and study a possibility of its practical application in high energy ground-based gamma-ray astronomy experiments (in particular, in TAIGA-HiSCORE). The approximation has a very good accuracy for individual showers and can be easily simplified for practical application in the HiSCORE wide angle timing array in the condition of a limited number of triggered stations.
Childhood Asthma Disparities in Chicago: Developing Approaches to Health Inequities.
Martin, Molly A; Kapheim, Melissa Gutierrez; Erwin, Kim; Ignoffo, Stacy; McMahon, Kate; OʼRourke, Amy; Gerald, Lynn B; Barrett, Meredith; Press, Valerie G; Darabi, Houshang; Krishnan, Jerry A
We conducted a needs assessment to develop an evidence-based, locally tailored asthma care implementation plan for high-risk children with asthma in Chicago. Our team of health policy experts, clinicians, researchers, and designers included extensive stakeholder engagement (N = 162) in a mixed-methods community needs assessment. Results showed the lines of communication and collaboration across sectors were weak; caregivers were the only consistent force and could not always manage this burden. A series of recommendations for interventions and how to implement and measure them were generated. Cooperative, multidisciplinary efforts grounded in the community can target wicked problems such as asthma.
An Automated Cloud-edge Detection Algorithm Using Cloud Physics and Radar Data
NASA Technical Reports Server (NTRS)
Ward, Jennifer G.; Merceret, Francis J.; Grainger, Cedric A.
2003-01-01
An automated cloud edge detection algorithm was developed and extensively tested. The algorithm uses in-situ cloud physics data measured by a research aircraft coupled with ground-based weather radar measurements to determine whether the aircraft is in or out of cloud. Cloud edges are determined when the in/out state changes, subject to a hysteresis constraint. The hysteresis constraint prevents isolated transient cloud puffs or data dropouts from being identified as cloud boundaries. The algorithm was verified by detailed manual examination of the data set in comparison to the results from application of the automated algorithm.
Acoustic Scattering by Near-Surface Inhomogeneities in Porous Media
1990-02-21
surfaces [8]. Recently, this empirical model has been replaced by a more rigorous mi- crostructural model [9]. Here, the acoustical characteristics of...boundaries. A discussion of how ground acoustic characteristics are modelled then follows, with the chapter being concluded by a brief summary. 3.1...of ground acoustic char- acteristics, with particular emphasis on the Four parameter model of Atten- borough, that will be used extensively later. 48
Fidelity study of the superconducting phase diagram in the two-dimensional single-band Hubbard model
NASA Astrophysics Data System (ADS)
Jia, C. J.; Moritz, B.; Chen, C.-C.; Shastry, B. Sriram; Devereaux, T. P.
2011-09-01
Extensive numerical studies have demonstrated that the two-dimensional single-band Hubbard model contains much of the key physics in cuprate high-temperature superconductors. However, there is no definitive proof that the Hubbard model truly possesses a superconducting ground state or, if it does, of how it depends on model parameters. To answer these longstanding questions, we study an extension of the Hubbard model including an infinite-range d-wave pair field term, which precipitates a superconducting state in the d-wave channel. Using exact diagonalization on 16-site square clusters, we study the evolution of the ground state as a function of the strength of the pairing term. This is achieved by monitoring the fidelity metric of the ground state, as well as determining the ratio between the two largest eigenvalues of the d-wave pair/spin/charge-density matrices. The calculations show a d-wave superconducting ground state in doped clusters bracketed by a strong antiferromagnetic state at half filling controlled by the Coulomb repulsion U and a weak short-range checkerboard charge ordered state at larger hole doping controlled by the next-nearest-neighbor hopping t'. We also demonstrate that negative t' plays an important role in facilitating d-wave superconductivity.
Systems Architecture for Fully Autonomous Space Missions
NASA Technical Reports Server (NTRS)
Esper, Jamie; Schnurr, R.; VanSteenberg, M.; Brumfield, Mark (Technical Monitor)
2002-01-01
The NASA Goddard Space Flight Center is working to develop a revolutionary new system architecture concept in support of fully autonomous missions. As part of GSFC's contribution to the New Millenium Program (NMP) Space Technology 7 Autonomy and on-Board Processing (ST7-A) Concept Definition Study, the system incorporates the latest commercial Internet and software development ideas and extends them into NASA ground and space segment architectures. The unique challenges facing the exploration of remote and inaccessible locales and the need to incorporate corresponding autonomy technologies within reasonable cost necessitate the re-thinking of traditional mission architectures. A measure of the resiliency of this architecture in its application to a broad range of future autonomy missions will depend on its effectiveness in leveraging from commercial tools developed for the personal computer and Internet markets. Specialized test stations and supporting software come to past as spacecraft take advantage of the extensive tools and research investments of billion-dollar commercial ventures. The projected improvements of the Internet and supporting infrastructure go hand-in-hand with market pressures that provide continuity in research. By taking advantage of consumer-oriented methods and processes, space-flight missions will continue to leverage on investments tailored to provide better services at reduced cost. The application of ground and space segment architectures each based on Local Area Networks (LAN), the use of personal computer-based operating systems, and the execution of activities and operations through a Wide Area Network (Internet) enable a revolution in spacecraft mission formulation, implementation, and flight operations. Hardware and software design, development, integration, test, and flight operations are all tied-in closely to a common thread that enables the smooth transitioning between program phases. The application of commercial software development techniques lays the foundation for delivery of product-oriented flight software modules and models. Software can then be readily applied to support the on-board autonomy required for mission self-management. An on-board intelligent system, based on advanced scripting languages, facilitates the mission autonomy required to offload ground system resources, and enables the spacecraft to manage itself safely through an efficient and effective process of reactive planning, science data acquisition, synthesis, and transmission to the ground. Autonomous ground systems in turn coordinate and support schedule contact times with the spacecraft. Specific autonomy software modules on-board include mission and science planners, instrument and subsystem control, and fault tolerance response software, all residing within a distributed computing environment supported through the flight LAN. Autonomy also requires the minimization of human intervention between users on the ground and the spacecraft, and hence calls for the elimination of the traditional operations control center as a funnel for data manipulation. Basic goal-oriented commands are sent directly from the user to the spacecraft through a distributed internet-based payload operations "center". The ensuing architecture calls for the use of spacecraft as point extensions on the Internet. This paper will detail the system architecture implementation chosen to enable cost-effective autonomous missions with applicability to a broad range of conditions. It will define the structure needed for implementation of such missions, including software and hardware infrastructures. The overall architecture is then laid out as a common thread in the mission life cycle from formulation through implementation and flight operations.
Agricultural peat lands; towards a greenhouse gas sink - a synthesis of a Dutch landscape study
NASA Astrophysics Data System (ADS)
Schrier-Uijl, A. P.; Kroon, P. S.; Hendriks, D. M. D.; Hensen, A.; Van Huissteden, J. C.; Leffelaar, P. A.; Berendse, F.; Veenendaal, E. M.
2013-06-01
It is generally known that managed, drained peatlands act as carbon sources. In this study we examined how mitigation through the reduction of management and through rewetting may affect the greenhouse gas (GHG) emission and the carbon balance of intensively managed, drained, agricultural peatlands. Carbon and GHG balances were determined for three peatlands in the western part of the Netherlands from 2005 to 2008 by considering spatial and temporal variability of emissions (CO2, CH4 and N2O). One area (Oukoop) is an intensively managed grass-on-peatland, including a dairy farm, with the ground water level at an average annual depth of 0.55 m below the soil surface. The second area (Stein) is an extensively managed grass-on-peatland, formerly intensively managed, with a dynamic ground water level at an average annual depth of 0.45 m below the soil surface. The third area is an (since 1998) rewetted former agricultural peatland (Horstermeer), close to Oukoop and Stein, with the average annual ground water level at a depth of 0.2 m below the soil surface. During the measurement campaigns we found that both agriculturally managed sites acted as carbon and GHG sources but the rewetted agricultural peatland acted as a carbon and GHG sink. The terrestrial GHG source strength was 1.4 kg CO2-eq m-2 yr-1 for the intensively managed area and 1.0 kg CO2-eq m-2 yr-1 for the extensively managed area; the unmanaged area acted as a GHG sink of 0.7 kg CO2-eq m-2 yr-1. Water bodies contributed significantly to the terrestrial GHG balance because of a high release of CH4 and the loss of DOC only played a minor role. Adding the farm-based CO2 and CH4 emissions increased the source strength for the managed sites to 2.7 kg CO2-eq m-2 yr-1 for Oukoop and 2.1 kg CO2-eq m-2 yr-1 for Stein. Shifting from intensively managed to extensively managed grass-on-peat reduced GHG emissions mainly because N2O emission and farm-based CH4 emissions decreased. Overall, this study suggests that managed peatlands are large sources of GHG and carbon, but, if appropriate measures are taken they can be turned back into GHG and carbon sinks within 15 yr of abandonment and rewetting.
Yura, Harold T; Fields, Renny A
2011-06-20
Level crossing statistics is applied to the complex problem of atmospheric turbulence-induced beam wander for laser propagation from ground to space. A comprehensive estimate of the single-axis wander angle temporal autocorrelation function and the corresponding power spectrum is used to develop, for the first time to our knowledge, analytic expressions for the mean angular level crossing rate and the mean duration of such crossings. These results are based on an extension and generalization of a previous seminal analysis of the beam wander variance by Klyatskin and Kon. In the geometrical optics limit, we obtain an expression for the beam wander variance that is valid for both an arbitrarily shaped initial beam profile and transmitting aperture. It is shown that beam wander can disrupt bidirectional ground-to-space laser communication systems whose small apertures do not require adaptive optics to deliver uniform beams at their intended target receivers in space. The magnitude and rate of beam wander is estimated for turbulence profiles enveloping some practical laser communication deployment options and suggesting what level of beam wander effects must be mitigated to demonstrate effective bidirectional laser communication systems.
NASA Astrophysics Data System (ADS)
Yepez-Martinez, Tochtli; Civitarese, Osvaldo; Hess, Peter O.
2018-02-01
Starting from an algebraic model based on the QCD-Hamiltonian and previously applied to study meson states, we have developed an extension of it in order to explore the structure of baryon states. In developing our approach we have adapted concepts taken from group theory and non-perturbative many-body methods to describe states built from effective quarks and anti-quarks degrees of freedom. As a Hamiltonian we have used the QCD Hamiltonian written in the Coulomb Gauge, and expressed it in terms of effective quark-antiquark, di-quarks and di-antiquark excitations. To gain some insights about the relevant interactions of quarks in hadronic states, the Hamiltonian was approximately diagonalized by mapping quark-antiquark pairs and di-quarks (di-antiquarks) onto phonon states. In dealing with the structure of the vacuum of the theory, color-scalar and color-vector states are introduced to account for ground-state correlations. While the use of a purely color-scalar ground state is an obvious choice, so that colorless hadrons contain at least three quarks, the presence of coupled color-vector pairs in the ground state allows for colorless excitations resulting from the action of color objects upon it.
Postnatal development under conditions of simulated weightlessness and space flight
NASA Technical Reports Server (NTRS)
Walton, K.
1998-01-01
The adaptability of the developing nervous system to environmental influences and the mechanisms underlying this plasticity has recently become a subject of interest in space neuroscience. Ground studies on neonatal rats using the tail suspension model of weightlessness have shown that the force of gravity clearly influences the events underlying the postnatal development of motor function. These effects depend on the age of the animal, duration of the perturbation and the motor function studied. A nine-day flight study has shown that a dam and neonates can develop under conditions of space flight. The motor function of the flight animals after landing was consistent with that seen in the tail suspension studies, being marked by limb joint extension. However, there were expected differences due to: (1) the unloading of the vestibular system in flight, which did not occur in the ground-based experiments; (2) differences between flight and suspension durations; and (3) the inability to evaluate motor function during the flight. The next step is to conduct experiments in space with the flexibility and rigor that is now limited to ground studies: an opportunity offered by the International Space Station. Copyright 1998 Published by Elsevier Science B.V.
Morelli, M; Masini, A; Simeone, E; Khazova, M
2016-08-31
We present an innovative satellite-based solar UV (ultraviolet) radiation dosimeter with a mobile app interface that has been validated by exploiting both ground-based measurements and an in vivo assessment of the erythemal effects on some volunteers having controlled exposure to solar radiation. The app with this satellite-based UV dosimeter also includes other related functionalities such as the provision of safe sun exposure time updated in real-time and end exposure visual/sound alert. Both validations showed that the system has a good accuracy and reliability needed for health-related applications. This app will be launched on the market by siHealth Ltd in May 2016 under the name of "HappySun" and is available for both Android and iOS devices (more info on ). Extensive R&D activities are on-going for the further improvement of the satellite-based UV dosimeter's accuracy.
Ground state energies from converging and diverging power series expansions
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lisowski, C.; Norris, S.; Pelphrey, R.
2016-10-15
It is often assumed that bound states of quantum mechanical systems are intrinsically non-perturbative in nature and therefore any power series expansion methods should be inapplicable to predict the energies for attractive potentials. However, if the spatial domain of the Schrödinger Hamiltonian for attractive one-dimensional potentials is confined to a finite length L, the usual Rayleigh–Schrödinger perturbation theory can converge rapidly and is perfectly accurate in the weak-binding region where the ground state’s spatial extension is comparable to L. Once the binding strength is so strong that the ground state’s extension is less than L, the power expansion becomes divergent,more » consistent with the expectation that bound states are non-perturbative. However, we propose a new truncated Borel-like summation technique that can recover the bound state energy from the diverging sum. We also show that perturbation theory becomes divergent in the vicinity of an avoided-level crossing. Here the same numerical summation technique can be applied to reproduce the energies from the diverging perturbative sums.« less
NASA Technical Reports Server (NTRS)
1981-01-01
A study was performed to determine the types of manned missions that will likely be performed in the late 1980's or early 1990's timeframe, to define MOTV configurations which satisfy these missions requirements, and to develop a program plan for its development. Twenty generic missions were originally defined for MOTV but, to simplify the selection process, five of these missions were selected as typical and used as Design Reference Missions. Systems and subsystems requirements were re-examined and sensitivity analyses performed to determine optimum point designs. Turnaround modes were considered to determine the most effective combination of ground based and spaced based activities. A preferred concept for the crew capsule and for the mission mode was developed.
Observations of marine stratocumulus clouds during FIRE
NASA Technical Reports Server (NTRS)
Albrecht, Bruce A.; Randall, David A.; Nicholls, Stephen
1988-01-01
The First International Satellite Cloud Climatology Project Regional Experiment (FIRE) to study extensive fields of stratocumulus clouds off the coast of California is presented. Measurements on the regional and detailed local scales were taken, allowing for a wide interpretation of the mean, turbulent, microphysical, radiative, and chemical characteristics of stratocumulus. Multiple aircraft and ground-based remote-sensing systems were used to study the time evolution of the boundary layer structure over a three-week period, and probes from tethered balloons were used to measure turbulence and to collect cloud-microphysical and cloud-radiative data. The observations provide a base for studying the generation maintenance and dissipation of stratocumulus clouds, and could aid in developing numerical models and improved methods for retrieving cloud properties by satellite.
The InSAR Scientific Computing Environment
NASA Technical Reports Server (NTRS)
Rosen, Paul A.; Gurrola, Eric; Sacco, Gian Franco; Zebker, Howard
2012-01-01
We have developed a flexible and extensible Interferometric SAR (InSAR) Scientific Computing Environment (ISCE) for geodetic image processing. ISCE was designed from the ground up as a geophysics community tool for generating stacks of interferograms that lend themselves to various forms of time-series analysis, with attention paid to accuracy, extensibility, and modularity. The framework is python-based, with code elements rigorously componentized by separating input/output operations from the processing engines. This allows greater flexibility and extensibility in the data models, and creates algorithmic code that is less susceptible to unnecessary modification when new data types and sensors are available. In addition, the components support provenance and checkpointing to facilitate reprocessing and algorithm exploration. The algorithms, based on legacy processing codes, have been adapted to assume a common reference track approach for all images acquired from nearby orbits, simplifying and systematizing the geometry for time-series analysis. The framework is designed to easily allow user contributions, and is distributed for free use by researchers. ISCE can process data from the ALOS, ERS, EnviSAT, Cosmo-SkyMed, RadarSAT-1, RadarSAT-2, and TerraSAR-X platforms, starting from Level-0 or Level 1 as provided from the data source, and going as far as Level 3 geocoded deformation products. With its flexible design, it can be extended with raw/meta data parsers to enable it to work with radar data from other platforms
Krause, Richard E.
1984-01-01
A compilation of ground-water data that have been collected for nearly 100 years in the coastal area of Georgia is presented in this report. The compilation of pertinent data indicates what information is available for use in the evaluation of the ground-water resources of the 13 counties of coastal Georgia. Also included in this report is a fairly complete discussion of previous and ongoing investigations and monitoring networks, and an extensive list of references. Maps at 1:24,000 and 1:1,000,000 scales contain well locations and identifiers for all wells in the Ground Water Site Inventory (GWSI) data base of the National Water Data Storage and retrieval System (WATSTORE). Tabular summaries of selected site information from GWSI, including well identifiers and names, latitude-longitude location, depth of well, altitude of land surface, and use of water are presented. Water-use data from the National Water Use Data System, and water use for irrigation from the University of Georgia, Department of Agriculture survey, also are tabulated. Also included are pertinent information on geophysical surveys and data obtained, and proposed project activities, particularly test-monitor well drilling. The data in this report were collected and compiled as part of the cooperative activities between the U.S. Geological Survey and other agencies.
Mapping the spawning grounds of North Sea cod (Gadus morhua) by direct and indirect means.
Fox, Clive J; Taylor, Martin; Dickey-Collas, Mark; Fossum, Petter; Kraus, Gerd; Rohlf, Norbert; Munk, Peter; van Damme, Cindy J G; Bolle, Loes J; Maxwell, David L; Wright, Peter J
2008-07-07
Despite recent evidence for sub-stock structuring, North Sea cod are assessed as a single unit. As a consequence, knowledge of sub-stock trends is poor. In particular, there are no recent evaluations of which spawning grounds are active. Here we report results from the first ichthyoplankton survey to cover the whole North Sea. Also, this survey, conducted in 2004, was the first to make extensive use of DNA-based molecular methods to unambiguously identify early developmental stage cod eggs. We compare the findings from the plankton survey with estimated egg production inferred from the distribution of mature cod in contemporaneous trawl surveys. Results from both approaches were in general agreement and showed hot spots of egg production around the southern and eastern edges of the Dogger Bank, in the German Bight, the Moray Firth and to the east of the Shetlands. These areas broadly coincide with known spawning locations from the period 1940 to 1970. We were, however, unable to directly detect significant numbers of cod eggs at the historic spawning ground off Flamborough (northeast coast of England). The results demonstrate that most of the major spawning grounds of cod in the North Sea are still active but that some localized populations may have been reduced to the point where it is now difficult to detect the presence of eggs in the plankton.
Mapping the spawning grounds of North Sea cod (Gadus morhua) by direct and indirect means
Fox, Clive J; Taylor, Martin; Dickey-Collas, Mark; Fossum, Petter; Kraus, Gerd; Rohlf, Norbert; Munk, Peter; van Damme, Cindy J.G; Bolle, Loes J; Maxwell, David L; Wright, Peter J
2008-01-01
Despite recent evidence for sub-stock structuring, North Sea cod are assessed as a single unit. As a consequence, knowledge of sub-stock trends is poor. In particular, there are no recent evaluations of which spawning grounds are active. Here we report results from the first ichthyoplankton survey to cover the whole North Sea. Also, this survey, conducted in 2004, was the first to make extensive use of DNA-based molecular methods to unambiguously identify early developmental stage cod eggs. We compare the findings from the plankton survey with estimated egg production inferred from the distribution of mature cod in contemporaneous trawl surveys. Results from both approaches were in general agreement and showed hot spots of egg production around the southern and eastern edges of the Dogger Bank, in the German Bight, the Moray Firth and to the east of the Shetlands. These areas broadly coincide with known spawning locations from the period 1940 to 1970. We were, however, unable to directly detect significant numbers of cod eggs at the historic spawning ground off Flamborough (northeast coast of England). The results demonstrate that most of the major spawning grounds of cod in the North Sea are still active but that some localized populations may have been reduced to the point where it is now difficult to detect the presence of eggs in the plankton. PMID:18397869
Effects of general principles of person transfer techniques on low back joint extension moment.
Katsuhira, Junji; Yamasaki, Syun; Yamamoto, Sumiko; Maruyama, Hitoshi
2010-01-01
The purpose of this study was to examine the effects of general principles of person transfer techniques specifically on the low back joint extension moment. These effects were examined by the following measurable quantitative parameters: 1) trunk bending angle, 2) knee flexion angle, 3) distance between the centers of gravity (COGs) of the caregiver and patient, representing the distance between the caregiver and patient, and 4) the vertical component of the ground reaction force representing the amount of the weight-bearing load on the caregiver's low back during transfers with and without assistive devices. Twenty students each took the role of caregiver, and one healthy adult simulated a patient. The participants performed three different transfer tasks: without any assistive device, with the patient wearing a low back belt, and with the caregiver using a transfer board. We found that the distance between the COGs and the vertical component of the ground reaction force, but not the trunk bending and knee flexion angles, were the variables that affected the low back joint extension moment. Our results suggest that the general principle of decreasing the distance between COGs is most effective for decreasing the low back joint extension moment during transfers under all conditions.
Application of Persistent Scatterer Radar Interferometry to the New Orleans delta region
NASA Astrophysics Data System (ADS)
Lohman, R.; Fielding, E.; Blom, R.
2007-12-01
Subsidence in New Orleans and along the Gulf Coast is currently monitored using a variety of ground- and satellite-based methods, and extensive geophysical modeling of the area seeks to understand the inputs to subsidence rates from sediment compaction, salt evacuation, oxidation and anthropogenic forcings such as the withdrawal or injection of subsurface fluids. Better understanding of the temporal and spatial variability of these subsidence rates can help us improve civic planning and disaster mitigation efforts with the goal of protecting lives and property over the long term. Existing ground-based surveys indicate that subsidence gradients of up to 1 cm/yr or more over length scales of several 10's of km exist in the region, especially in the vicinity of the city of New Orleans. Modeling results based on sediment inputs and post-glacial sea level change tend to predict lower gradients, presumably because there is a large input from unmodeled crustal faults and anthropogenic activity. The broad spatial coverage of InSAR can both add to the existing network of ground-based geodetic surveys, and can help to identify areas that are deforming anomalously with respect to surrounding areas. Here we present the use of a modified point scatterer method applied to radar data from the Radarsat satellite for New Orleans and the Gulf Coast. Point target analysis of InSAR data has already been successfully applied to the New Orleans area by Dixon et al (2006). Our method is similar to the Stanford Method for PS (StaMPS) developed by Andy Hooper, adapted to rely on combinations of small orbital baselines and the inclusion of coherent regions from the time span of each interferogram during phase unwrapping rather than only using points that are stable within all interferograms.
Mixed-field GCR Simulations for Radiobiological Research using Ground Based Accelerators
NASA Astrophysics Data System (ADS)
Kim, Myung-Hee Y.; Rusek, Adam; Cucinotta, Francis
Space radiation is comprised of a large number of particle types and energies, which have differential ionization power from high energy protons to high charge and energy (HZE) particles and secondary neutrons produced by galactic cosmic rays (GCR). Ground based accelerators such as the NASA Space Radiation Laboratory (NSRL) at Brookhaven National Laboratory (BNL) are used to simulate space radiation for radiobiology research and dosimetry, electronics parts, and shielding testing using mono-energetic beams for single ion species. As a tool to support research on new risk assessment models, we have developed a stochastic model of heavy ion beams and space radiation effects, the GCR Event-based Risk Model computer code (GERMcode). For radiobiological research on mixed-field space radiation, a new GCR simulator at NSRL is proposed. The NSRL-GCR simulator, which implements the rapid switching mode and the higher energy beam extraction to 1.5 GeV/u, can integrate multiple ions into a single simulation to create GCR Z-spectrum in major energy bins. After considering the GCR environment and energy limitations of NSRL, a GCR reference field is proposed after extensive simulation studies using the GERMcode. The GCR reference field is shown to reproduce the Z and LET spectra of GCR behind shielding within 20 percents accuracy compared to simulated full GCR environments behind shielding. A major challenge for space radiobiology research is to consider chronic GCR exposure of up to 3-years in relation to simulations with cell and animal models of human risks. We discuss possible approaches to map important biological time scales in experimental models using ground-based simulation with extended exposure of up to a few weeks and fractionation approaches at a GCR simulator.
Mixed-field GCR Simulations for Radiobiological Research Using Ground Based Accelerators
NASA Technical Reports Server (NTRS)
Kim, Myung-Hee Y.; Rusek, Adam; Cucinotta, Francis A.
2014-01-01
Space radiation is comprised of a large number of particle types and energies, which have differential ionization power from high energy protons to high charge and energy (HZE) particles and secondary neutrons produced by galactic cosmic rays (GCR). Ground based accelerators such as the NASA Space Radiation Laboratory (NSRL) at Brookhaven National Laboratory (BNL) are used to simulate space radiation for radiobiology research and dosimetry, electronics parts, and shielding testing using mono-energetic beams for single ion species. As a tool to support research on new risk assessment models, we have developed a stochastic model of heavy ion beams and space radiation effects, the GCR Event-based Risk Model computer code (GERMcode). For radiobiological research on mixed-field space radiation, a new GCR simulator at NSRL is proposed. The NSRL-GCR simulator, which implements the rapid switching mode and the higher energy beam extraction to 1.5 GeV/u, can integrate multiple ions into a single simulation to create GCR Z-spectrum in major energy bins. After considering the GCR environment and energy limitations of NSRL, a GCR reference field is proposed after extensive simulation studies using the GERMcode. The GCR reference field is shown to reproduce the Z and LET spectra of GCR behind shielding within 20% accuracy compared to simulated full GCR environments behind shielding. A major challenge for space radiobiology research is to consider chronic GCR exposure of up to 3-years in relation to simulations with cell and animal models of human risks. We discuss possible approaches to map important biological time scales in experimental models using ground-based simulation with extended exposure of up to a few weeks and fractionation approaches at a GCR simulator.
Glaciation and regional ground-water flow in the Fennoscandian Shield: Site 94
Provost, Alden M.; Voss, Clifford I.; Neuzil, C.E.
1998-01-01
Results from a regional-scale ground-water flow model of the Fennoscandian shield suggest that ground-water flow is strongly affected by surface conditions associated with climatic change and glaciation. The model was used to run a series of numerical simulations of variable-density ground-water flow in a 1500-km-long and approximately 10-km-deep cross-section that passes through southern Sweden. Ground-water flow and shield brine transport in the cross-sectional model are controlled by an assumed time evolution of surface conditions over the next 140 ka. Simulations show that, under periglacial conditions, permafrost may locally or extensively impede the free recharge or discharge of ground water. Below cold-based glacial ice, no recharge or discharge of ground water occurs. Both of these conditions result in the settling of shield brine and consequent freshening of near-surface water in areas of natural discharge blocked by permafrost. The presence of warm-based ice with basal melting creates a potential for ground-water recharge rates much larger than under present, ice-free conditions. Recharging basal meltwater can reach depths of a few kilometers in a few thousand years. The vast majority of recharged water is accommodated through storage in the volume of bedrock below the local area of recharge; regional (lateral) redistribution of recharged water by subsurface flow is minor over the duration of a glacial advance (~10 ka). During glacial retreat, the weight of the ice overlying a given surface location decreases, and significant upward flow of ground water may occur below the ice sheet due to pressure release, despite the continued potential for recharge of basal meltwater. Excess meltwater must exit from below the glacier through subglacial cavities and channels. Subsurface penetration of meltwater during glacial advance and up-flow during glacial retreat are greatest if the loading efficiency of the shield rock is low. The maximum rate of ground-water discharge occurs at the receding ice margin, and some discharge occurs below incursive post-glacial seas. The simulation results suggest that vertical movement of deep shield brines induced by the next few glacial cycles should not increase the concentration of dissolved solids significantly above present-day levels. However, the concentration of dissolved solids should decrease significantly at depths of up to several kilometers during periods of glacial meltwater recharge. The meltwater may reside in the subsurface for periods exceeding 10 ka and may bring oxygenated conditions to an otherwise reducing chemical environment.
NASA Astrophysics Data System (ADS)
Massa, Marco; Barani, Simone; Lovati, Sara
2014-06-01
The paper presents an extensive review of topographic effects in seismology taking into account the knowledge of 40 yr of scientific literature. An overview of topographic effects based on experimental observations and numerical modelling is presented with the aim of highlighting meaning and causes of these phenomena as well as possible correlations between site response (fundamental frequency, amplification level) and geometrical (width and shape ratio of a relief) parameters. After a thorough summary of topographic effects, the paper focuses on five Italian sites whose seismic response is potentially affected by local morphology, as already evidenced by previous studies. In this study, seismic data recorded at these sites are analysed computing directional spectral ratios both in terms of horizontal to vertical spectral ratios (HVSRs) and, wherever possible, in terms of standard spectral ratios (SSRs). The analysis lead to the conclusion that wavefield tends to be polarized along a direction perpendicular to the main axis of a topographic irregularity, direction along which ground motion amplification is maximum. The final section of the article compares and contrasts different spectral ratio techniques in order to examine their effectiveness and reliability in detecting topographic effects. The examples discussed in the paper show that site responses based on HVSRs rather than SSR measurements could lead to misinterpretation of ground response results, both as concerns the definition of the site fundamental frequency and amplification level. Results and findings of this work will be used as starting point to discuss the influence of topographic effects on ground motion prediction equations and regulations for design. These topics will be discussed in the companion article.
Multijoint kinetic chain analysis of knee extension during the soccer instep kick.
Naito, Kozo; Fukui, Yosuke; Maruyama, Takeo
2010-04-01
Although previous studies have shown that motion-dependent interactions between adjacent segments play an important role in producing knee extension during the soccer instep kick, detailed knowledge about the mechanisms underlying those interactions is lacking. The present study aimed to develop a 3-D dynamical model for the multijoint kinetic chain of the instep kick in order to quantify the contributions of the causal dynamical factors to the production of maximum angular velocity during knee extension. Nine collegiate soccer players volunteered to participate in the experiment and performed instep kicking movements while 3-D positional data and the ground reaction force were measured. A dynamical model was developed in the form of a linked system containing 8 segments and 18 joint rotations, and the knee extension/flexion motion was decomposed into causal factors related to muscular moment, gyroscopic moment, centrifugal force, Coriolis force, gravity, proximal endpoint linear acceleration, and external force-dependent terms. The rapid knee extension during instep kicking was found to result almost entirely from kicking leg centrifugal force, trunk rotation muscular moment, kicking leg Coriolis force, and trunk rotation gyroscopic-dependent components. Based on the finding that rapid knee extension during instep kicking stems from multiple dynamical factors, it is suggested that the multijoint kinetic chain analysis used in the present study is more useful for achieving a detailed understanding of the cause of rapid kicking leg movement than the previously used 2-D, two-segment kinetic chain model. The present results also indicated that the centrifugal effect due to the kicking hip flexion angular velocity contributed substantially to the generation of a rapid knee extension, suggesting that the adjustment between the kicking hip flexion angular velocity and the leg configuration (knee flexion angle) is more important for effective instep kicking than other joint kinematics.
Order by disorder and gaugelike degeneracy in a quantum pyrochlore antiferromagnet.
Henley, Christopher L
2006-02-03
The (three-dimensional) pyrochlore lattice antiferromagnet with Heisenberg spins of large spin length S is a highly frustrated model with a macroscopic degeneracy of classical ground states. The zero-point energy of (harmonic-order) spin-wave fluctuations distinguishes a subset of these states. I derive an approximate but illuminating effective Hamiltonian, acting within the subspace of Ising spin configurations representing the collinear ground states. It consists of products of Ising spins around loops, i.e., has the form of a Z2 lattice gauge theory. The remaining ground-state entropy is still infinite but not extensive, being O(L) for system size O(L3). All these ground states have unit cells bigger than those considered previously.
1025: MAGIC 2010 Multi Autonomous Ground International Challenge. Volume I
2010-10-22
the creation of software required to interact with the sensors for each subsystem. Most of the systems have been extensively developed and tested with...varying levels of success. All of the systems have been developed from the ground up and have been discussed in the report. 15. SUBJECT TERMS...the system . The system was broken down into several components. These were: (i) The ability to perform accurate localisation both indoors and outside
NASA: Model development for human factors interfacing
NASA Technical Reports Server (NTRS)
Smith, L. L.
1984-01-01
The results of an intensive literature review in the general topics of human error analysis, stress and job performance, and accident and safety analysis revealed no usable techniques or approaches for analyzing human error in ground or space operations tasks. A task review model is described and proposed to be developed in order to reduce the degree of labor intensiveness in ground and space operations tasks. An extensive number of annotated references are provided.
Sprites, elf transients, and positive ground strokes
DOE Office of Scientific and Technical Information (OSTI.GOV)
Boccippio, D.J.; Boldi, R.; Williams, E.R.
1995-08-25
In two summertime mesoscale convective systems (MCSs), mesospheric optical sprite phenomena were often coincident with both large-amplitude positive cloud-to-ground lightning and transient Schumann resonance excitations of the entire Earth-ionosphere cavity. These observations, together with earlier studies of MCS electrification, suggest that sprites are triggered when the rapid removal of large quantities of positive charge from an areally extensive charge layer stresses the mesosphere to dielectric breakdown. 46 refs., 7 figs., 1 tab.
Foster, Helen L.; Karlstrom, Thor N.V.
1967-01-01
The great 1964 Alaska earthquake caused considerable ground breakage in the Cook Inlet area of south-central Alaska. The breakage occurred largely in thick deposits of unconsolidated sediments. The most important types of ground breakage were (1) fracturing or cracking and the extrusion of sand and gravel with ground water along fractures in various types of landforms, and (2) slumping and lateral extension of unconfined faces, particularly along delta fronts. The principal concentration of ground breakage within the area covered by this report was in a northeast-trending zone about 60 miles long and 6 miles wide in the northern part of the Kenai Lowland. The zone cut across diverse topography and stratigraphy. Cracks were as much as 30 feet across and 25 feet deep. Sand, gravel, and pieces of coal and lignite were extruded along many fissures. It is suggested that the disruption in this zone may be due to movement along a fault in the underlying Tertiary rocks. The outwash deltas of Tustumena and Skilak Lakes in the Kenai Lowland, of Eklutna Lake and Lake George in the Chugach Mountains, of Bradley Lake in the Kenai Mountains, and at the outlet of upper Beluga Lake at the base of the Alaska Range showed much slumping, as did the delta of the Susitna River. Parts of the flood plains of the Skilak River, Fox River, and Eagle River were extensively cracked. A few avalanches and slumps occurred along the coast of Cook Inlet in scattered localities. Some tidal flats were cracked. However, in view of the many thick sections of unconsolidated sediments and the abundance of steep slopes, the cracking was perhaps less than might have been expected. Observations along the coasts indicated changes in sea level which, although caused partly by compaction of unconsolidated sediments, may largely be attributed to crus1tal deformation accompanying the earthquake. Most of the Cook Inlet area was downwarped, although the northwest side of Cook Inlet may have been slightly unwarped. Maximum change in the Cook Inlet area was probably less than 6 feet. Little or no regional tilting was detected in the lake basins of Tustumena and Skilak Lakes.
Coastal flood inundation monitoring with Satellite C-band and L-band Synthetic Aperture Radar data
Ramsey, Elijah W.; Rangoonwala, Amina; Bannister, Terri
2013-01-01
Satellite Synthetic Aperture Radar (SAR) was evaluated as a method to operationally monitor the occurrence and distribution of storm- and tidal-related flooding of spatially extensive coastal marshes within the north-central Gulf of Mexico. Maps representing the occurrence of marsh surface inundation were created from available Advanced Land Observation Satellite (ALOS) Phased Array type L-Band SAR (PALSAR) (L-band) (21 scenes with HH polarizations in Wide Beam [100 m]) data and Environmental Satellite (ENVISAT) Advanced SAR (ASAR) (C-band) data (24 scenes with VV and HH polarizations in Wide Swath [150 m]) during 2006-2009 covering 500 km of the Louisiana coastal zone. Mapping was primarily based on a decrease in backscatter between reference and target scenes, and as an extension of previous studies, the flood inundation mapping performance was assessed by the degree of correspondence between inundation mapping and inland water levels. Both PALSAR- and ASAR-based mapping at times were based on suboptimal reference scenes; however, ASAR performance seemed more sensitive to reference-scene quality and other types of scene variability. Related to water depth, PALSAR and ASAR mapping accuracies tended to be lower when water depths were shallow and increased as water levels decreased below or increased above the ground surface, but this pattern was more pronounced with ASAR. Overall, PALSAR-based inundation accuracies averaged 84% (n = 160), while ASAR-based mapping accuracies averaged 62% (n = 245).
The need for the vegetarian crew for long-term LSS
NASA Astrophysics Data System (ADS)
Gorgolewski, S.
The long-term space missions pose very stringent demands on the high degree of closure levels. One obvious requirements is to assure the human crew a steady state self-supporting and self-regenerating LSS environment. The strictly vegetarian crew is the primary requirement to minimize the cost and weight of the spacecraft. This ensures the minimal matter circulation problems, because we can also use for food as many as possible fuly edible plants with nex to none, non digestable plant tissues. One important task is to select a range of plants which should satisfy the nutritional needs of the crew for a long-term, in the range of several years. Preliminary fitotron experiments with lettuce, demonstrated that one can achieve this goal, with a plant which is wholy edible even with the roots. This has been achieved with the use of several teens times stronger electrical field, than the 130 V/m fair weather global atmospheric electrical field. More experiments are in progress for the extension of the list of such vegetarian food. The selection of suitable plants which meet these highly demanding selection criteria, has to be done and can be done in ground based experiments. Plants ensure one important requirements of a closed loop CO2 and O2 circulation with the vegetarian crew in the loop. Extensive research programs are needed for this purpose using large ground based instalations like the Biosphere 2. The success of the use of electrical fields as replacement of gravitational field in the fitotron which proved the dominating role over gravity, of several kV/m electical field intensities. It also proves the feasibility of improving the crop productivity in ground based greenhouses, provided that we do restore inside the missing in "normal" designs our global electrical field. The fair weather electrical field (not to mention the enhanced field) is the missing vital environmental factor which has been systematically "overlooked" in practically all greenhouses. It is the most likely factor whi ch was the main culprit of the failure of the manned long term Biosphere 2 experiment. Very strong evidence has been achieved in fitotron experiments, which have already been presented and published in the COSPAR2000 publication.
Spectral mapping of comet 67P/Churyumov-Gerasimenko with VLT/MUSE and SINFONI
NASA Astrophysics Data System (ADS)
Guilbert-Lepoutre, Aurelie; Besse, Sebastien; Snodgrass, Colin; Yang, Bin
2016-10-01
Comets are supposedly the most primitive objects in the solar system, preserving the earliest record of material from the nebula out of which our Sun and planets were formed, and thus holding crucial clues on the early phases of the solar system formation and evolution. For most small bodies in the solar system we can only access the surface properties, whereas active comet nuclei lose material from their subsurface, so that understanding cometary activity represents an unique opportunity to assess their internal composition, and by extension the composition, the temperature and pressure conditions of the protoplanetary disk at their place of formation.The ESA/Rosetta mission is performing the most thorough investigation of a comet ever made. Rosetta is measuring properties of comet 67P/Churyumov-Gerasimenko at distances between 5 and hundreds of km from the nucleus. However, it is unable to make any measurement over the thousands of km of the rest of the coma. Fortunately, the outer coma is accessible from the ground. In addition, we currently lack an understanding of how the very detailed information gathered from space-based observations can be extrapolated to the many ground-based observations that we can potentially perform. Combining parallel in situ observations with observations from the ground therefore gives us a great opportunity, not only to understand the behavior of 67P, but also to other comets observed exclusively from Earth. As part of the many observations taken from the ground, we have performed a spectral mapping of 67's coma using two IFU instruments mounted on the VLT: MUSE in the visible, and SINFONI in the near-infrared. The observations, carried out in March 2016, will be presented and discussed.
End-of-winter snow depth variability on glaciers in Alaska
NASA Astrophysics Data System (ADS)
McGrath, Daniel; Sass, Louis; O'Neel, Shad; Arendt, Anthony; Wolken, Gabriel; Gusmeroli, Alessio; Kienholz, Christian; McNeil, Christopher
2015-08-01
A quantitative understanding of snow thickness and snow water equivalent (SWE) on glaciers is essential to a wide range of scientific and resource management topics. However, robust SWE estimates are observationally challenging, in part because SWE can vary abruptly over short distances in complex terrain due to interactions between topography and meteorological processes. In spring 2013, we measured snow accumulation on several glaciers around the Gulf of Alaska using both ground- and helicopter-based ground-penetrating radar surveys, complemented by extensive ground truth observations. We found that SWE can be highly variable (40% difference) over short spatial scales (tens to hundreds of meters), especially in the ablation zone where the underlying ice surfaces are typically rough. Elevation provides the dominant basin-scale influence on SWE, with gradients ranging from 115 to 400 mm/100 m. Regionally, total accumulation and the accumulation gradient are strongly controlled by a glacier's distance from the coastal moisture source. Multiple linear regressions, used to calculate distributed SWE fields, show that robust results require adequate sampling of the true distribution of multiple terrain parameters. Final SWE estimates (comparable to winter balances) show reasonable agreement with both the Parameter-elevation Relationships on Independent Slopes Model climate data set (9-36% difference) and the U.S. Geological Survey Alaska Benchmark Glaciers (6-36% difference). All the glaciers in our study exhibit substantial sensitivity to changing snow-rain fractions, regardless of their location in a coastal or continental climate. While process-based SWE projections remain elusive, the collection of ground-penetrating radar (GPR)-derived data sets provides a greatly enhanced perspective on the spatial distribution of SWE and will pave the way for future work that may eventually allow such projections.
Ground-based Observations for the Asteroid Itokawa
NASA Astrophysics Data System (ADS)
Ishiguro, M.; Tholen, D. J.; Hasegawa, S.; Abe, M.; Sekiguchi, T.; Ostro, S. J.; Kaasalainen, M.
Apollo-type near-Earth asteroid (25143) Itokawa is a target of the asteroid explorer "HAYABUSA" launched in May 2003. On March 29, 2001, Itokawa was close to the Earth at a minimum distance of 0.038 AU. During the apparition, vigorous ground-based observations have performed. Multi-band photometry (e.g. ECAS and Johnson-Cousins photometric system) and spectroscopy in visible and near-infrared revealed that Itokawa is classified as an S(IV)-type asteroid, and the surface composition is like an anhydrous ordinary chondrite. The extensive photometric campaign data indicate that the rotation is retrograde (i.e., the pole orientation of the asteroid is south of the ecliptic plane) and its rotational period is 12 hr. From the mid-infrared observation, Itokawa is found to be a sub-km size. Detail three dimensional model was constructed based on both the radar observations and the optical lightcurve. Moreover, the bulk density determined by radar observations is 2.5 g/cc. Generally, the results obtained by optical, infrared and radar observations are consistent with each other. These observational results provide constraints on the thermal and optical design of Hayabusa spacecraft and its scientific devices. In this paper, we review these results mentioned above. In addition, we are planning to introduce the latest results obtained during the apparition in 2004.
Discovery of a blue whale feeding and nursing ground in southern Chile.
Hucke-Gaete, Rodrigo; Osman, Layla P; Moreno, Carlos A; Findlay, Ken P; Ljungblad, Don K
2004-01-01
After the extensive exploitation that reduced the Southern Hemisphere blue whale (Balaenoptera musculus) populations to less than 3% of its original numbers, studies on its recovery have been compounded by the inaccessibility of most populations and the extensive migrations between low and high latitudes, thus ensuring that knowledge about blue whale ecology and status remains limited. We report the recent discovery of, arguably, the most important blue whale feeding and nursing ground known to date in the Southern Hemisphere, which is located near the fjords off southern Chile. Through aerial and marine surveys (n = 7) 47 groups, comprising 153 blue whales including at least 11 mother-calf pairs, were sighted during the austral summer and early autumn of 2003. The implications of this discovery on the biological understanding and conservation of this endangered species are discussed. PMID:15252974
Discovery of a blue whale feeding and nursing ground in southern Chile.
Hucke-Gaete, Rodrigo; Osman, Layla P; Moreno, Carlos A; Findlay, Ken P; Ljungblad, Don K
2004-05-07
After the extensive exploitation that reduced the Southern Hemisphere blue whale (Balaenoptera musculus) populations to less than 3% of its original numbers, studies on its recovery have been compounded by the inaccessibility of most populations and the extensive migrations between low and high latitudes, thus ensuring that knowledge about blue whale ecology and status remains limited. We report the recent discovery of, arguably, the most important blue whale feeding and nursing ground known to date in the Southern Hemisphere, which is located near the fjords off southern Chile. Through aerial and marine surveys (n = 7) 47 groups, comprising 153 blue whales including at least 11 mother-calf pairs, were sighted during the austral summer and early autumn of 2003. The implications of this discovery on the biological understanding and conservation of this endangered species are discussed.
Ran, Shi-Ju
2016-05-01
In this work, a simple and fundamental numeric scheme dubbed as ab initio optimization principle (AOP) is proposed for the ground states of translational invariant strongly correlated quantum lattice models. The idea is to transform a nondeterministic-polynomial-hard ground-state simulation with infinite degrees of freedom into a single optimization problem of a local function with finite number of physical and ancillary degrees of freedom. This work contributes mainly in the following aspects: (1) AOP provides a simple and efficient scheme to simulate the ground state by solving a local optimization problem. Its solution contains two kinds of boundary states, one of which play the role of the entanglement bath that mimics the interactions between a supercell and the infinite environment, and the other gives the ground state in a tensor network (TN) form. (2) In the sense of TN, a novel decomposition named as tensor ring decomposition (TRD) is proposed to implement AOP. Instead of following the contraction-truncation scheme used by many existing TN-based algorithms, TRD solves the contraction of a uniform TN in an opposite way by encoding the contraction in a set of self-consistent equations that automatically reconstruct the whole TN, making the simulation simple and unified; (3) AOP inherits and develops the ideas of different well-established methods, including the density matrix renormalization group (DMRG), infinite time-evolving block decimation (iTEBD), network contractor dynamics, density matrix embedding theory, etc., providing a unified perspective that is previously missing in this fields. (4) AOP as well as TRD give novel implications to existing TN-based algorithms: A modified iTEBD is suggested and the two-dimensional (2D) AOP is argued to be an intrinsic 2D extension of DMRG that is based on infinite projected entangled pair state. This paper is focused on one-dimensional quantum models to present AOP. The benchmark is given on a transverse Ising chain and 2D classical Ising model, showing the remarkable efficiency and accuracy of the AOP.
SMART-OLEV—An orbital life extension vehicle for servicing commercial spacecrafts in GEO
NASA Astrophysics Data System (ADS)
Kaiser, Clemens; Sjöberg, Fredrik; Delcura, Juan Manuel; Eilertsen, Baard
2008-07-01
Orbital Satellite Services Limited (OSSL) is a satellite servicing company that is developing an orbit life extension vehicle (OLEV) to extend the operational lifetime of geostationary satellites. The industrial consortium of SSC (Sweden), Kayser-Threde (Germany) and Sener (Spain) is in charge to develop and industrialize the space and ground segment. It is a fully commercial program with support of several space agencies during the development phase. The business plan is based on life extension for high value commercial satellites while also providing the satellite operators with various fleet management services such as graveyard burns, slot transfers and on orbit protection against replacement satellite or launch failures. The OLEV spacecraft will be able to dock with a geostationary satellite and uses an electrical propulsion system to extend its life by taking over the attitude control and station keeping functions. The OLEV system is building on the SMART-1 platform developed by Swedish Space Corporation. It was developed for ESA as a technology test-bed to demonstrate the use of electrical propulsion for interplanetary orbit transfer manoeuvres. The concept is called SMART-OLEV and takes advantage of the low cost, low mass SMART-1 platform by a maximum use of recurrent platform technology.
Cosmological constraints from strong gravitational lensing in clusters of galaxies.
Jullo, Eric; Natarajan, Priyamvada; Kneib, Jean-Paul; D'Aloisio, Anson; Limousin, Marceau; Richard, Johan; Schimd, Carlo
2010-08-20
Current efforts in observational cosmology are focused on characterizing the mass-energy content of the universe. We present results from a geometric test based on strong lensing in galaxy clusters. Based on Hubble Space Telescope images and extensive ground-based spectroscopic follow-up of the massive galaxy cluster Abell 1689, we used a parametric model to simultaneously constrain the cluster mass distribution and dark energy equation of state. Combining our cosmological constraints with those from x-ray clusters and the Wilkinson Microwave Anisotropy Probe 5-year data gives Omega(m) = 0.25 +/- 0.05 and w(x) = -0.97 +/- 0.07, which are consistent with results from other methods. Inclusion of our method with all other available techniques brings down the current 2sigma contours on the dark energy equation-of-state parameter w(x) by approximately 30%.
Ground water security and drought in Africa: linking availability, access, and demand.
Calow, Roger C; Macdonald, Alan M; Nicol, Alan L; Robins, Nick S
2010-01-01
Drought in Africa has been extensively researched, particularly from meteorological, agricultural, and food security perspectives. However, the impact of drought on water security, particularly ground water dependent rural water supplies, has received much less attention. Policy responses have concentrated on food needs, and it has often been difficult to mobilize resources for water interventions, despite evidence that access to safe water is a serious and interrelated concern. Studies carried out in Ghana, Malawi, South Africa, and Ethiopia highlight how rural livelihoods are affected by seasonal stress and longer-term drought. Declining access to food and water is a common and interrelated problem. Although ground water plays a vital role in buffering the effects of rainfall variability, water shortages and difficulties in accessing water that is available can affect domestic and productive water uses, with knock-on effects on food consumption and production. Total depletion of available ground water resources is rarely the main concern. A more common scenario is a spiral of water insecurity as shallow water sources fail, additional demands are put on remaining sources, and mechanical failures increase. These problems can be planned for within normal development programs. Water security mapping can help identify vulnerable areas, and changes to monitoring systems can ensure early detection of problems. Above all, increasing the coverage of ground water-based rural water supplies, and ensuring that the design and siting of water points is informed by an understanding of hydrogeological conditions and user demand, can significantly increase the resilience of rural communities to climate variability.
The Scintillation Prediction Observations Research Task (SPORT) Mission
NASA Astrophysics Data System (ADS)
Spann, J. F.; Swenson, C.; Durão, O.; Loures, L.; Heelis, R. A.; Bishop, R. L.; Le, G.; Abdu, M. A.; Habash Krause, L.; De Nardin, C. M.; Fonseca, E.
2015-12-01
Structure in the charged particle number density in the equatorial ionosphere can have a profound impact on the fidelity of HF, VHF and UHF radio signals that are used for ground-to-ground and space-to-ground communication and navigation. The degree to which such systems can be compromised depends in large part on the spatial distribution of the structured regions in the ionosphere and the background plasma density in which they are embedded. In order to address these challenges it is necessary to accurately distinguish the background ionospheric conditions that favor the generation of irregularities from those that do not. Additionally we must relate the evolution of those conditions to the subsequent evolution of the irregular plasma regions themselves. The background ionospheric conditions are conveniently described by latitudinal profiles of the plasma density at nearly constant altitude, which describe the effects of ExB drifts and neutral winds, while the appearance and growth of plasma structure requires committed observations from the ground from at least one fixed longitude. This talk will present an international collaborative CubeSat mission called SPORT that stands for Scintillation Prediction Observations Research Task. This mission that will advance our understanding of the nature and evolution of ionospheric structures around sunset to improve predictions of disturbances that affect radio propagation and telecommunication signals. The science goals will be accomplished by a unique combination of satellite observations from a nearly circular middle inclination orbit and the extensive operation of ground based observations from South America near the magnetic equator. This approach promises Explorer class science at a CubeSat price.
The Scintillation Prediction Observations Research Task (SPORT) Mission
NASA Astrophysics Data System (ADS)
Spann, James; Le, Guan; Swenson, Charles; Denardini, Clezio Marcos; Bishop, Rebecca L.; Abdu, Mangalathayil A.; Cupertino Durao, Otavio S.; Heelis, Roderick; Loures, Luis; Krause, Linda; Fonseca, Eloi
2016-07-01
Structure in the charged particle number density in the equatorial ionosphere can have a profound impact on the fidelity of HF, VHF and UHF radio signals that are used for ground-to-ground and space-to-ground communication and navigation. The degree to which such systems can be compromised depends in large part on the spatial distribution of the structured regions in the ionosphere and the background plasma density in which they are embedded. In order to address these challenges it is necessary to accurately distinguish the background ionospheric conditions that favor the generation of irregularities from those that do not. Additionally we must relate the evolution of those conditions to the subsequent evolution of the irregular plasma regions themselves. The background ionospheric conditions are conveniently described by latitudinal profiles of the plasma density at nearly constant altitude, which describe the effects of ExB drifts and neutral winds, while the appearance and growth of plasma structure requires committed observations from the ground from at least one fixed longitude. This talk will present an international collaborative CubeSat mission called SPORT that stands for the Scintillation Prediction Observations Research Task. This mission will advance our understanding of the nature and evolution of ionospheric structures around sunset to improve predictions of disturbances that affect radio propagation and telecommunication signals. The science goals will be accomplished by a unique combination of satellite observations from a nearly circular middle inclination orbit and the extensive operation of ground based observations from South America near the magnetic equator. This approach promises Explorer class science at a CubeSat price.
The Scintillation Prediction Observations Research Task (SPORT) Mission
NASA Astrophysics Data System (ADS)
Spann, James; Swenson, Charles; Durão, Otavio; Loures, Luis; Heelis, Rod; Bishop, Rebecca; Le, Guan; Abdu, Mangalathayil; Krause, Linda; Nardin, Clezio; Fonseca, Eloi
2016-04-01
Structure in the charged particle number density in the equatorial ionosphere can have a profound impact on the fidelity of HF, VHF and UHF radio signals that are used for ground-to-ground and space-to-ground communication and navigation. The degree to which such systems can be compromised depends in large part on the spatial distribution of the structured regions in the ionosphere and the background plasma density in which they are embedded. In order to address these challenges it is necessary to accurately distinguish the background ionospheric conditions that favor the generation of irregularities from those that do not. Additionally we must relate the evolution of those conditions to the subsequent evolution of the irregular plasma regions themselves. The background ionospheric conditions are conveniently described by latitudinal profiles of the plasma density at nearly constant altitude, which describe the effects of ExB drifts and neutral winds, while the appearance and growth of plasma structure requires committed observations from the ground from at least one fixed longitude. This talk will present an international collaborative CubeSat mission called SPORT that stands for the Scintillation Prediction Observations Research Task. This mission will advance our understanding of the nature and evolution of ionospheric structures around sunset to improve predictions of disturbances that affect radio propagation and telecommunication signals. The science goals will be accomplished by a unique combination of satellite observations from a nearly circular middle inclination orbit and the extensive operation of ground based observations from South America near the magnetic equator. This approach promises Explorer class science at a CubeSat price.
Ground-water provinces of Brazil
Schneider, Robert
1962-01-01
As part of a study of the status of investigations and development of ground water in Brazil, made under the auspices of the United States International Cooperation Administration and with the cooperation of the Government of Brazil, the country was divided into seven ground-water provinces. The identification and delineation of the provinces were based on the regional distribution of the dominant geologic units which are known or inferred to have distinctive water-bearing characteristics. Three of the provinces, covering most of the country, are underlain by Precambrian crystalline rocks. Three others coincide in part with four extensive sedimentary basins--the Parnaiba or Maranhfio basin and the contiguous Sao Francisco basin in the northeast and east, the Amazon basin in the north and northwest, and the Paranfi basin in the south and southwest. In addition, the narrow, discontinuous coastal plain is considered as a province. the occurrence of ground water is discussed briefly, and pertinent data are given on the more important aquifers, together with information on some existing wells. Because of the widespread distribution of crystalline rocks of low permeability, it is difficult in many areas to develop large or even adequate ground-water supplies. In general, satisfactory supplies of water are available in most of the rest of the country. Some problems include the relative deficiency of rainfall in the northeast together with the occurrence, in parts of this region, of mineralized water in the crystalline rocks. Also, there is a potential problem of excessive lowering of water levels and interference among wells in the intensively developed area of the city of Sao Paulo.
Machining of Silicon-Ribbon-Forming Dies
NASA Technical Reports Server (NTRS)
Menna, A. A.
1985-01-01
Carbon extension for dies used in forming silicon ribbon crystals machined precisely with help of special tool. Die extension has edges beveled toward narrow flats at top, with slot precisely oriented and centered between flats and bevels. Cutting tool assembled from standard angle cutter and circular saw or saws. Angle cutters cuts bevels while slot saw cuts slot between them. In alternative version, custom-ground edges or additional circular saws also cut flats simultaneously.
NASA Astrophysics Data System (ADS)
Melo, D.; Yelós, L. D.; Garcia, B.; Rovero, A. C.
2017-10-01
Gamma-ray astronomy opened the universe of the more energetic electromagnetic radiation using ground and orbiting instruments, which provide information for the understanding of sources of different types. Ground-based telescope arrays use Cherenkov light produced by the charged particles from extensive air showers generated in the Earth's atmosphere to identify gamma rays. This imposes a minimum energy threshold on the gamma rays to be detected. Towards the high-energy end of the spectrum, however, the amount of Cherenkov radiation produced by a gamma-ray photon guarantees its detectability, the limiting factor being the low flux of the sources. For this reason, the detection strategy consists in using arrays of small telescopes. In this work, we investigate the feasibility of detecting gamma-ray cascades using Cherenkov telescopes, in the range of 100 GeV to 2 TeV, at the CASLEO site, characterizing the response of a system of three Cherenkov telescopes.
Handheld hyperspectral imager for standoff detection of chemical and biological aerosols
NASA Astrophysics Data System (ADS)
Hinnrichs, Michele; Jensen, James O.; McAnally, Gerard
2004-08-01
Pacific Advanced Technology has developed a small hand held imaging spectrometer, Sherlock, for gas leak and aerosol detection and imaging. The system is based on a patented technique, (IMSS Image Multi-spectral Sensing), that uses diffractive optics and image processing algorithms to detect spectral information about objects in the scene of the camera. This cameras technology has been tested at Dugway Proving Ground and Dstl Porton Down facilities looking at Chemical and Biological agent simulants. In addition to Chemical and Biological detection, the camera has been used for environmental monitoring of green house gases and is currently undergoing extensive laboratory and field testing by the Gas Technology Institute, British Petroleum and Shell Oil for applications for gas leak detection and repair. In this paper we will present some of the results from the data collection at the TRE test at Dugway Proving Ground during the summer of 2002 and laboratory testing at the Dstl facility at Porton Down in the UK in the fall of 2002.
Overview of SnowEx Year 1 Activities
NASA Technical Reports Server (NTRS)
Kim, Edward; Gatebe, Charles; Hall, Dorothy; Newlin, Jerry; Misakonis, Amy; Elder, Kelly; Marshall, Hans Peter; Heimstra, Chris; Brucker, Ludovic; De Marco, Eugenia;
2017-01-01
SnowEx is a multi-year airborne snow campaign with the primary goal of addressing the question: How much water is stored in Earths terrestrial snow-covered regions? Year 1 (2016-17) focused on the distribution of snow-water equivalent (SWE) and the snow energy balance in a forested environment. The year 1 primary site was Grand Mesa and the secondary site was the Senator Beck Basin, both in western, Colorado, USA. Nine sensors on five aircraft made observations using a broad range of sensing techniques, active and passive microwave, and active and passive optical infrared to determine the sensitivity and accuracy of these potential satellite remote sensing techniques, along with models, to measure snow under a range of forest conditions. SnowEx also included an extensive range of ground truth measurements in-situ manual samples, snow pits, ground based remote sensing measurements, and sophisticated new techniques. A detailed description of the data collected will be given and some preliminary results will be presented.
Combined Aero and Underhood Thermal Analysis for Heavy Duty Trucks
DOE Office of Scientific and Technical Information (OSTI.GOV)
Vegendla, Prasad; Sofu, Tanju; Saha, Rohit
2017-01-31
Aerodynamic analysis of the medium-duty delivery truck was performed to achieve vehicle design optimization. Three dimensional CFD simulations were carried out for several improved designs, with a detailed external component analysis of wheel covers, side skirts, roof fairings, and rounded trailer corners. The overall averaged aerodynamics drag reduction through the design modifications were shown up to 22.3% through aerodynamic considerations alone, which is equivalent to 11.16% fuel savings. The main identified fuel efficiencies were based on second generation devices, including wheel covers, side skirts, roof fairings, and rounded trailer corners. The important findings of this work were; (i) the optimummore » curvature radius of the rounded trailer edges found to be 125 mm, with an arc length of 196.3 mm, (ii) aerodynamic drag reduction increases with dropping clearance of side skirts between wheels and ground, and (iii) aerodynamic drag reduction increases with an extension of front bumper towards the ground.« less
Data Gathering and Energy Transfer Dilemma in UAV-Assisted Flying Access Network for IoT
Arabi, Sara; Sadik, Mohamed
2018-01-01
Recently, Unmanned Aerial Vehicles (UAVs) have emerged as an alternative solution to assist wireless networks, thanks to numerous advantages they offer in comparison to terrestrial fixed base stations. For instance, a UAV can be used to embed a flying base station providing an on-demand nomadic access to network services. A UAV can also be used to wirelessly recharge out-of-battery ground devices. In this paper, we aim to deal with both data collection and recharging depleted ground Internet-of-Things (IoT) devices through a UAV station used as a flying base station. To extend the network lifetime, we present a novel use of UAV with energy harvesting module and wireless recharging capabilities. However, the UAV is used as an energy source to empower depleted IoT devices. On one hand, the UAV charges depleted ground IoT devices under three policies: (1) low-battery first scheme; (2) high-battery first scheme; and (3) random scheme. On the other hand, the UAV station collects data from IoT devices that have sufficient energy to transmit their packets, and in the same phase, the UAV exploits the Radio Frequency (RF) signals transmitted by IoT devices to extract and harvest energy. Furthermore, and as the UAV station has a limited coverage time due to its energy constraints, we propose and investigate an efficient trade-off between ground users recharging time and data gathering time. Furthermore, we suggest to control and optimize the UAV trajectory in order to complete its travel within a minimum time, while minimizing the energy spent and/or enhancing the network lifetime. Extensive numerical results and simulations show how the system behaves under different scenarios and using various metrics in which we examine the added value of UAV with energy harvesting module. PMID:29751662
Experimental Evaluation of an Integrated Datalink and Automation-Based Strategic Trajectory Concept
NASA Technical Reports Server (NTRS)
Mueller, Eric
2007-01-01
This paper presents research on the interoperability of trajectory-based automation concepts and technologies with modern Flight Management Systems and datalink communication available on many of today s commercial aircraft. A tight integration of trajectory-based ground automation systems with the aircraft Flight Management System through datalink will enable mid-term and far-term benefits from trajectory-based automation methods. A two-way datalink connection between the trajectory-based automation resident in the Center/TRACON Automation System and the Future Air Navigation System-1 integrated FMS/datalink in NASA Ames B747-400 Level D simulator has been established and extensive simulation of the use of datalink messages to generate strategic trajectories completed. A strategic trajectory is defined as an aircraft deviation needed to solve a conflict or honor a route request and then merge the aircraft back to its nominal preferred trajectory using a single continuous trajectory clearance. Engineers on the ground side of the datalink generated lateral and vertical trajectory clearances and transmitted them to the Flight Management System of the 747; the airborne automation then flew the new trajectory without human intervention, requiring the flight crew only to review and to accept the trajectory. This simulation established the protocols needed for a significant majority of the trajectory change types required to solve a traffic conflict or deviate around weather. This demonstration provides a basis for understanding the requirements for integration of trajectory-based automation with current Flight Management Systems and datalink to support future National Airspace System operations.
NASA Technical Reports Server (NTRS)
Idris, Husni; Shen, Ni; Wing, David J.
2011-01-01
The growing demand for air travel is increasing the need for mitigating air traffic congestion and complexity problems, which are already at high levels. At the same time new surveillance, navigation, and communication technologies are enabling major transformations in the air traffic management system, including net-based information sharing and collaboration, performance-based access to airspace resources, and trajectory-based rather than clearance-based operations. The new system will feature different schemes for allocating tasks and responsibilities between the ground and airborne agents and between the human and automation, with potential capacity and cost benefits. Therefore, complexity management requires new metrics and methods that can support these new schemes. This paper presents metrics and methods for preserving trajectory flexibility that have been proposed to support a trajectory-based approach for complexity management by airborne or ground-based systems. It presents extensions to these metrics as well as to the initial research conducted to investigate the hypothesis that using these metrics to guide user and service provider actions will naturally mitigate traffic complexity. The analysis showed promising results in that: (1) Trajectory flexibility preservation mitigated traffic complexity as indicated by inducing self-organization in the traffic patterns and lowering traffic complexity indicators such as dynamic density and traffic entropy. (2)Trajectory flexibility preservation reduced the potential for secondary conflicts in separation assurance. (3) Trajectory flexibility metrics showed potential application to support user and service provider negotiations for minimizing the constraints imposed on trajectories without jeopardizing their objectives.
NASA Technical Reports Server (NTRS)
Moran, M. S.; Goodrich, D. C.; Kustas, W. P.
1994-01-01
A research and modeling strategy is presented for development of distributed hydrologic models given by a combination of remotely sensed and ground based data. In support of this strategy, two experiments Moonsoon'90 and Walnut Gulch'92 were conducted in a semiarid rangeland southeast of Tucson, Arizona, (U.S.) and a third experiment, the SALSA-MEX (Semi Arid Land Surface Atmospheric Mountain Experiment) was proposed. Results from the Moonsoon'90 experiment substantially advanced the understanding of the hydrologic and atmospheric fluxes in an arid environment and provided insight into the use of remote sensing data for hydrologic modeling. The Walnut Gulch'92 experiment addressed the seasonal hydrologic dynamics of the region and the potential of combined optical microwave remote sensing for hydrologic applications. SALSA-MEX will combine measurements and modeling to study hydrologic processes influenced by surrounding mountains, such as enhanced precipitation, snowmelt and recharge to ground water aquifers. The results from these experiments, along with the extensive experimental data bases, should aid the research community in large scale modeling of mass and energy exchanges across the soil-plant-atmosphere interface.
Overview of the DACCIWA ground-based field campaign in southern West Africa
NASA Astrophysics Data System (ADS)
Lohou, Fabienne; Kalthoff, Norbert; Brooks, Barbara; Jegede, Gbenga; Adler, Bianca; Ajao, Adewale; Ayoola, Muritala; Babić, Karmen; Bessardon, Geoffrey; Delon, Claire; Dione, Cheikh; Handwerker, Jan; Jambert, Corinne; Kohler, Martin; Lothon, Marie; Pedruzo-Bagazgoitia, Xabier; Smith, Victoria; Sunmonu, Lukman; Wieser, Andreas; Derrien, Solène
2017-04-01
During June and July 2016, a ground-based field campaign took place in southern West Africa within the framework of the Dynamics-aerosol-chemistry-cloud interactions in West Africa (DACCIWA) project. In the investigated region, extended low-level stratus clouds form very frequently during night-time and persist long into the following day influencing the diurnal cycle of the atmospheric boundary layer and, hence, the regional climate. The motivation for the measurements was to identify the meteorological controls on the whole process chain from the formation of nocturnal stratus clouds, via the daytime transition to convective clouds and the formation of deep precipitating clouds. During the measurement period, extensive remote sensing and in-situ measurements were performed at three supersites in Kumasi (Ghana), Savè (Benin) and Ile-Ife (Nigeria). The gathered observations included the energy-balance components at the Earth's surface, the mean and turbulent conditions in the nocturnal and daytime ABL as well as the de- and entrainment processes between the ABL and the free troposphere. The meteorological measurements were supplemented by aerosol and air-chemistry observations. We will give an overview of the conducted measurements including instrument availability and strategy during intensive observation periods.
NASA Technical Reports Server (NTRS)
Parrish, A.; Dezafra, R. L.; Solomon, P. M.; Barrett, J. W.
1988-01-01
Recent concern over possible long term stratospheric changes caused by the introduction of man-made compounds has increased the need for instrumentation that can accurately measure stratospheric minor constituents. The technique of radio spectroscopy at millimeter wavelengths was first used to observe rotational transitions of stratospheric ozone nearly two decades ago, but has not been highly developed until recently. A ground-based observing technique is reported which employs a millimeter-wave superheterodyne receiver and multichannel filter spectrometer for measurements of stratospheric constituents that have peak volume mixing ratios that are less than 10 to the -9th, more than 3 orders of magnitude less than that for ozone. The technique is used for an extensive program of observations of stratospheric chlorine monoxide and also for observations of other stratospheric trace gases such as (O-16)3, vibrationally excited (O-16)3, (O-18)2(O-16), N2O, HO2, and HCN. In the present paper, analysis of the observing technique is given, including the method of calibration and analysis of sources of error. The technique is found to be a reliable means of observing and monitoring important stratospheric trace constituents.
NASA Technical Reports Server (NTRS)
Katembe, W. J.; Edelmann, R. E.; Brinckmann, E.; Kiss, J. Z.
1998-01-01
Experiments with Arabidopsis have been developed for spaceflight studies in the European Space Agency's Biorack module. The Biorack is a multiuser facility that is flown on the United States Space Shuttle and serves as a small laboratory for studying cell and developmental biology in unicells, plants, and small invertebrates. The purpose of our spaceflight research was to investigate the starch-statolith model for gravity perception by studying wild-type (WT) and three starch-deficient mutants of Arabidopsis. Since spaceflight opportunities for biological experimentation are scarce, the extensive ground-based testing described in this paper is needed to ensure the success of a flight project. Therefore, the specific aims of our ground-based research were: (1) to modify the internal configuration of the flight hardware, which originally was designed for large lentil seeds, to accommodate small Arabidopsis seeds; (2) to maximize seed germination in the hardware; and (3) to develop favorable conditions in flight hardware for the growth and gravitropism of seedlings. The hardware has been modified, and growth conditions for Arabidopsis have been optimized. These experiments were successfully flown on two Space Shuttle missions in 1997.
NASA Astrophysics Data System (ADS)
Sánchez-Naranjo, S.; Rincón, W.; Ramos-Pollán, R.; González, F. A.; Soley, S.
2017-04-01
Ground Based Augmentation Systems GBAS provide differential corrections to approaching and landing aircrafts in the vicinities of an airport. The ionosphere can introduce an error not accountable by those differential corrections, and a threat model for the Conterminous United States region CONUS was developed in order to consider the highest gradients measured. This study presents the first extensive analysis of ionospheric gradients for Ecuador, from data fully covering 2013 and 2014 collected by their national Global Navigation Satellite System GNSS monitoring network (REGME). In this work it is applied an automated methodology adapted for low latitudes for processing data from dual frequency receivers networks, by considering data from all available days in the date range of the study regardless the geomagnetic indices values. The events found above the CONUS threat model occurred during days of nominal geomagnetic indices, confirming: (1) the higher bounds required for an ionospheric threat model for Ecuador, and (2) that geomagnetic indices are not enough to indicate relevant ionospheric anomalies in low latitude regions, reinforcing the necessity of a continuous monitoring of ionosphere. As additional contribution, the events database is published online, making it available to other researchers.
Solving the Mystery of the Short-Hard Gamma-Ray Bursts
NASA Astrophysics Data System (ADS)
Fox, Derek
2004-07-01
Seven years after the afterglow detections that revolutionized studies of the long-soft gamma-ray bursts, not even one afterglow of a short-hard GRB has been seen, and the nature of these events has become one of the most important problems in GRB research. The forthcoming Swift satellite will report few-arcsecond localizations for short-hard bursts in minutes, however, enabling prompt, deep optical afterglow searches for the first time. Discovery and observation of the first short-hard optical afterglows will answer most of the critical questions about these events: What are their distances and energies? Do they occur in distant galaxies, and if so, in which regions of those galaxies? Are they the result of collimated or quasi-spherical explosions? In combination with an extensive rapid-response ground-based campaign, we propose to make the critical high-sensitivity HST TOO observations that will allow us to answer these questions. If theorists are correct in attributing the short-hard bursts to binary neutron star coalescence events, then the short-hard bursts are signposts to the primary targeted source population for ground-based gravitational-wave detectors, and short-hard burst studies will have a vital role to play in guiding their observations.
NASA Technical Reports Server (NTRS)
Kelton, K. F.; Gangopadhyay, Anup K.; Lee, G. W.; Hyers, Robert W.; Rathz, T. J.; Robinson, Michael B.; Rogers, Jan R.
2003-01-01
From extensive ground based work on the phase diagram and undercooling studies of Ti-Zr-Ni alloys, have clearly identified the composition of three different phases with progressively increasing polytetrahedral order such as, (Ti/Zr), the C14 Laves phase, and the i-phase, that nucleate directly from the undercooled liquid. The reduced undercooling decreases progressively with increasing polytetrahedral order in the solid, supporting Frank s hypothesis. A new facility for direct measurements of the structures and phase transitions in undercooled liquids (BESL) was developed and has provided direct proof of the primary nucleation of a metastable icosahedral phase in some Ti-Zr-Ni alloys. The first measurements of specific heat and viscosity in the undercooled liquid of this alloy system have been completed. Other than the importance of thermo-physical properties for modeling nucleation and growth processes in these materials, these studies have also revealed some interesting new results (such as a maximum of C(sup q, sub p) in the undercooled state). These ground-based results have clearly established the necessary background and the need for conducting benchmark nucleation experiments at the ISS on this alloy system.
NASA Technical Reports Server (NTRS)
Tzvi, G. C.
1986-01-01
A technique to deduce the virtual temperature from the combined use of the equations of fluid dynamics, observed wind and observed radiances is described. The wind information could come from ground-based sensitivity very high frequency (VHF) Doppler radars and/or from space-borne Doppler lidars. The radiometers are also assumed to be either space-borne and/or ground-based. From traditional radiometric techniques the vertical structure of the temperature can be estimated only crudely. While it has been known for quite some time that the virtual temperature could be deduced from wind information only, such techniques had to assume the infallibility of certain diagnostic relations. The proposed technique is an extension of the Gal-Chen technique. It is assumed that due to modeling uncertainties the equations of fluid dynamics are satisfied only in the least square sense. The retrieved temperature, however, is constrained to reproduce the observed radiances. It is shown that the combined use of the three sources of information (wind, radiances and fluid dynamical equations) can result in a unique determination of the vertical temperature structure with spatial and temporal resolution comparable to that of the observed wind.
NASA Astrophysics Data System (ADS)
Liu, Tianhui; Chen, Jun; Zhang, Zhaojun; Shen, Xiangjian; Fu, Bina; Zhang, Dong H.
2018-04-01
We constructed a nine-dimensional (9D) potential energy surface (PES) for the dissociative chemisorption of H2O on a rigid Ni(100) surface using the neural network method based on roughly 110 000 energies obtained from extensive density functional theory (DFT) calculations. The resulting PES is accurate and smooth, based on the small fitting errors and the good agreement between the fitted PES and the direct DFT calculations. Time dependent wave packet calculations also showed that the PES is very well converged with respect to the fitting procedure. The dissociation probabilities of H2O initially in the ground rovibrational state from 9D quantum dynamics calculations are quite different from the site-specific results from the seven-dimensional (7D) calculations, indicating the importance of full-dimensional quantum dynamics to quantitatively characterize this gas-surface reaction. It is found that the validity of the site-averaging approximation with exact potential holds well, where the site-averaging dissociation probability over 15 fixed impact sites obtained from 7D quantum dynamics calculations can accurately approximate the 9D dissociation probability for H2O in the ground rovibrational state.
Fabry-Perot Based Radiometers for Precise Measurement of Greenhouse Gases
NASA Technical Reports Server (NTRS)
Heaps, William S.; Wilson, Emily L.; Georgieva, Elena
2007-01-01
Differential radiometers based upon the Fabry-Perot interferometer have been developed and demonstrated that exhibit very great sensitivity to changes in the atmospheric column of carbon dioxide, oxygen, and water vapor. These instruments employ a solid Fabry-Perot etalon that is tuned to the proper wavelength by changing the temperature. By choosing the thickness of the etalon its multiple pass bands can be made to align with regularly space absorption features of the molecule under investigation. Use of multiple absorption features improves the optical throughput of the instrument and improves the stability of the instrument response with respect to environmental changes. Efforts are underway at Goddard to extend this technique to the carbon 13 isotope of carbon dioxide and to methane. These instruments are intrinsically rugged and can be made rather small and inexpensively. They therefore hold promise for widespread use in ground based networks for calibration of satellite instruments such as OCO and GOSAT. Results will be presented for ground based and airborne operations for these systems. The effects of atmospheric scattering, pointing errors, pressure broadening and temperature effects will be discussed with regard to achieving precision better than .5% required for validation of carbon dioxide column measured from space. Designs permitting the extension of the technique to an even larger number of atmospheric species will be discussed along with theoretical analysis of potential system performance.
The Pearson-Readhead Survey from Space
NASA Technical Reports Server (NTRS)
Preston, R. A.; Tingay, S. J.; Jones, D. L.; Lister, M.; Piner, G.; Murphy, D. W.; Meier, D. L.; Pearson, T. J.; Readhead, A. C. S.; Hirabayashi, H.;
1988-01-01
The VSOP Space VLBI mission uses the HALCA spacecraft, launched from Japan in February 1997, in conjunction with ground radio observatories around the world to create a high resolution radio-wave length imaging facility. We are using this unique facility to observe a complete sample of Pearson-Readhead Survey sources at 4.8 GHz to determine core brightness temperatures and pc-scale jet properties. The Pearson-Readhead sample has been used for extensive ground-based VLBI survey studies. This sample is ideal for a VSOP survey because the sources are strong, the VSOP u-v coverages are especially good above +350 declination, and multi-epoch ground-based VLBI data and other existing supporting data on these sources exceeds that of any other possible sample. We have chosen to observe a complete subset of this sample that is most likely to show fringes on space-earth baselines. To date we have imaged a majority of the 31 sources in our sample. In addition, we are obtaining matched- resolution 15 GHz observations using the VLBA at epochs close in time to the space VLBI observations to investigate the spectral indices of the source components at high resolution. We gratefully acknowledge the VSOP Project, which is led by the Japanese Institute of Space and Astronautical Science in cooperation with many organizations and radio telescopes around the world. This research was performed in part at the Jet Propulsion Laboratory, California Institute of Technology, under contract to NASA.
Airport technology international 1993
NASA Astrophysics Data System (ADS)
Papagiorcopulo, George
The present survey of developments in airport technologies and their management discusses airport extensions and upgradings, airport developments in China, polluter penalization, airport effects on environments, European ground-handling methods, ATC in Europe, EC duty-free sales at airports, and the privatization of airport security. Also discussed are airport advertising, new alternatives in air-cargo handling, ATC training, taxi-guidance systems, and the reduction of fuel consumption and emissions on the ground. (No individual items are abstracted in this volume)
NASA Astrophysics Data System (ADS)
Cigna, Francesca; Jordan, Hannah; Bateson, Luke; McCormack, Harry; Roberts, Claire
2015-11-01
We combine geological data and ground motion estimates from satellite ERS-1/2 and ENVISAT persistent scatterer interferometry (PSI) to delineate areas of observed natural and anthropogenic geohazards in the administrative area of Greater London (United Kingdom). This analysis was performed within the framework of the EC FP7-SPACE PanGeo project, and by conforming to the interpretation and geohazard mapping methodology extensively described in the Production Manual (cf. http://www.pangeoproject.eu). We discuss the results of the generation of the PanGeo digital geohazard mapping product for Greater London, and analyse the potential of PSI, geological data and the PanGeo methodology to identify areas of observed geohazards. Based on the analysis of PSI ground motion data sets for the years 1992-2000 and 2002-2010 and geology field campaigns, we identify 25 geohazard polygons, covering a total of ~650 km2. These include not only natural processes such as compaction of deposits on the River Thames flood plain and slope instability, but also anthropogenic instability due to groundwater management and changes in the Chalk aquifer, recent engineering works such as those for the Jubilee Line Extension project and electricity tunnelling in proximity to the River Thames, and the presence of made ground. In many instances, natural and anthropogenic observed geohazards overlap, therefore indicating interaction of different processes over the same areas. In terms of ground area covered, the dominant geohazard is anthropogenic land subsidence caused by groundwater abstraction for a total of ~300 km2, followed by natural compression of River Thames sediments over ~105 km2. Observed ground motions along the satellite line-of-sight are as high as +29.5 and -25.3 mm/year, and indicate a combination of land surface processes comprising ground subsidence and uplift, as well as downslope movements. Across the areas of observed geohazards, urban land cover types from the Copernicus (formerly GMES) EEA European Urban Atlas, e.g., continuous and discontinuous urban fabric and industrial units, show the highest average velocities away from the satellite sensor, and the smallest standard deviations (~0.7-1.0 mm/year). More rural land cover types such as agricultural, semi-natural and green areas reveal the highest spatial variability (up to ~4.4 mm/year), thus suggesting greater heterogeneity of observed motion rates within these land cover types. Areas of observed motion in the PSI data for which a geological interpretation cannot be found with sufficient degree of certainty are also identified, and their possible causes discussed. Although present in Greater London, some geohazard types such as shrink-swell clays and ground dissolution are not highlighted by the interpretation of PSI annual motion rates. Reasons for absence of evidence of the latter in the PSI data are discussed, together with difficulties related to the identification of good radar scatterers in landsliding areas.
MTBE OXIDATION BY BIFUNCTIONAL ALUMINUN
Bifunctional aluminum, prepared by sulfating zero-valent aluminum with sulfuric acid, is an innovative extension of zero-valent metal (ZVM) technology for ground water remediation. Bifunctional aluminum has a dual functionality of simultaneously decomposing both reductively- an...
Site Selection for Hvdc Ground Electrodes
NASA Astrophysics Data System (ADS)
Freire, P. F.; Pereira, S. Y.
2014-12-01
High-Voltage Direct Current (HVDC) transmission systems are composed of a bipole transmission line with a converter substation at each end. Each substation may be equipped with a HVDC ground electrode, which is a wide area (up to 1 km Ø) and deep (from 3 to 100m) electrical grounding. When in normal operation, the ground electrode will dissipate in the soil the unbalance of the bipole (~1.5% of the rated current). When in monopolar operation with ground return, the HVDC electrode will inject in the soil the nominal pole continuous current, of about 2000 to 3000 Amperes, continuously for a period up to a few hours. HVDC ground electrodes site selection is a work based on extensive geophysical and geological surveys, in order to attend the desired design requirements established for the electrodes, considering both its operational conditions (maximum soil temperature, working life, local soil voltage gradients etc.) and the interference effects on the installations located up to 50 km away. This poster presents the geophysical investigations conducted primarily for the electrodes site selection, and subsequently for the development of the crust resistivity model, which will be used for the interference studies. A preliminary site selection is conducted, based on general geographical and geological criteria. Subsequently, the geology of each chosen area is surveyed in detail, by means of electromagnetic/electrical geophysical techniques, such as magnetotelluric (deep), TDEM (near-surface) and electroresistivity (shallow). Other complementary geologic and geotechnical surveys are conducted, such as wells drilling (for geotechnical characterization, measurement of the water table depth and water flow, and electromagnetic profiling), and soil and water sampling (for measurement of thermal parameters and evaluation of electrosmosis risk). The site evaluation is a dynamic process along the surveys, and some sites will be discarded. For the two or three final sites, the inversion of the combined deep, near-surface and shallow apparent resistivity curves, results in the layered crust resistivity models. These models will allow for the preliminary interference studies, that will result on the selection of the final electrode site (one for each converter substation).
NASA Technical Reports Server (NTRS)
Casper, Paul W.; Bent, Rodney B.
1991-01-01
The algorithm used in previous technology time-of-arrival lightning mapping systems was based on the assumption that the earth is a perfect spheroid. These systems yield highly-accurate lightning locations, which is their major strength. However, extensive analysis of tower strike data has revealed occasionally significant (one to two kilometer) systematic offset errors which are not explained by the usual error sources. It was determined that these systematic errors reduce dramatically (in some cases) when the oblate shape of the earth is taken into account. The oblate spheroid correction algorithm and a case example is presented.
Low Gravity Freefall Facilities
NASA Technical Reports Server (NTRS)
1981-01-01
Composite of Marshall Space Flight Center's Low-Gravity Free Fall Facilities.These facilities include a 100-meter drop tower and a 100-meter drop tube. The drop tower simulates in-flight microgravity conditions for up to 4.2 seconds for containerless processing experiments, immiscible fluids and materials research, pre-flight hardware design test and flight experiment simulation. The drop tube simulates in-flight microgravity conditions for up to 4.6 seconds and is used extensively for ground-based microgravity convection research in which extremely small samples are studied. The facility can provide deep undercooling for containerless processing experiments that require materials to remain in a liquid phase when cooled below the normal solidification temperature.
RNA viruses in trypanosomatid parasites: a historical overview
Grybchuk, Danyil; Kostygov, Alexei Y; Macedo, Diego H; d’Avila-Levy, Claudia M; Yurchenko, Vyacheslav
2018-01-01
Viruses of trypanosomatids are now being extensively studied because of their diversity and the roles they play in flagellates’ biology. Among the most prominent examples are leishmaniaviruses implicated in pathogenesis of Leishmania parasites. Here, we present a historical overview of this field, starting with early reports of virus-like particles on electron microphotographs, and culminating in detailed molecular descriptions of viruses obtained using modern next generation sequencing-based techniques. Because of their diversity, different life cycle strategies and host specificity, we believe that trypanosomatids are a fertile ground for further explorations to better understand viral evolution, routes of transitions, and molecular mechanisms of adaptation to different hosts. PMID:29513877
RNA viruses in trypanosomatid parasites: a historical overview.
Grybchuk, Danyil; Kostygov, Alexei Y; Macedo, Diego H; d'Avila-Levy, Claudia M; Yurchenko, Vyacheslav
2018-02-19
Viruses of trypanosomatids are now being extensively studied because of their diversity and the roles they play in flagellates' biology. Among the most prominent examples are leishmaniaviruses implicated in pathogenesis of Leishmania parasites. Here, we present a historical overview of this field, starting with early reports of virus-like particles on electron microphotographs, and culminating in detailed molecular descriptions of viruses obtained using modern next generation sequencing-based techniques. Because of their diversity, different life cycle strategies and host specificity, we believe that trypanosomatids are a fertile ground for further explorations to better understand viral evolution, routes of transitions, and molecular mechanisms of adaptation to different hosts.
Aging Aircraft Transparencies: AN Italian Air Force Fleet Case History
NASA Astrophysics Data System (ADS)
Caucci, D.; Aiello, L.; Bagnoli, F.; Bernabei, M.
2008-08-01
Aircraft acrylic transparencies are structural components that must withstand flight and ground loads. Crazing occurrence, known as Environmental Stress Cracking (ESC), causes their substitution during aircraft maintenance operations. This form of aging is mainly a physical phenomenon due to the interaction of transparencies base material with an active liquid and leads craze formation at lower stress that would be required in air. In this paper, an extensive phenomenon of network ESC occurred on transparencies of many aircrafts operating in the same fleet was investigated. Cover application while parking was found to be the critical aspect in crazing appearance, thus acting as physical shield for condensed water and heat transferring.
Observations of emission lines in M supergiants
NASA Technical Reports Server (NTRS)
Lambert, D. L.
1979-01-01
Copernicus observations of Mg 2 h and k emission lines from M giants and supergiants are described. Supergiants with extensive circumstellar gas shells show an asymmetric k line. The asymmetry is ascribed to superimposed lines of Fe 1 and Mn 1. The Mg 2 line width fit the Wilson-Bappu relation derived from observations of G and K Stars. Results of correlated ground-based observations include (1) the discovery of K 1 fluorescent emission from the Betelgeuse shell; (2) extimates of the mass-loss rates; and (3) the proposal that silicate dust grains must account for the major fraction of the Si atoms in the Betelgeuse shell.
1981-03-30
Composite of Marshall Space Flight Center's Low-Gravity Free Fall Facilities.These facilities include a 100-meter drop tower and a 100-meter drop tube. The drop tower simulates in-flight microgravity conditions for up to 4.2 seconds for containerless processing experiments, immiscible fluids and materials research, pre-flight hardware design test and flight experiment simulation. The drop tube simulates in-flight microgravity conditions for up to 4.6 seconds and is used extensively for ground-based microgravity convection research in which extremely small samples are studied. The facility can provide deep undercooling for containerless processing experiments that require materials to remain in a liquid phase when cooled below the normal solidification temperature.
NASA Technical Reports Server (NTRS)
1991-01-01
CRRES is a program to study the space environment which surrounds Earth and the effects of space radiation on modern satellite electronic systems. The satellite will carry an array of active experiments including chemical releases and a complement of sophisticated scientific instruments to accomplish these objectives. Other chemical release active experiments will be performed with suborbital rocket probes. These chemical releases will paint the magnetic and electric fields in Earthspace with clouds of glowing ions. Earthspace will be a laboratory, and the releases will be studied with an extensive network of ground-, aircraft-, and satellite-based diagnostic instruments.
Report of the panel on international programs
NASA Technical Reports Server (NTRS)
Anderson, Allen Joel; Fuchs, Karl W.; Ganeka, Yasuhiro; Gaur, Vinod; Green, Andrew A.; Siegfried, W.; Lambert, Anthony; Rais, Jacub; Reighber, Christopher; Seeger, Herman
1991-01-01
The panel recommends that NASA participate and take an active role in the continuous monitoring of existing regional networks, the realization of high resolution geopotential and topographic missions, the establishment of interconnection of the reference frames as defined by different space techniques, the development and implementation of automation for all ground-to-space observing systems, calibration and validation experiments for measuring techniques and data, the establishment of international space-based networks for real-time transmission of high density space data in standardized formats, tracking and support for non-NASA missions, and the extension of state-of-the art observing and analysis techniques to developing nations.
Extravehicular activities guidelines and design criteria
NASA Technical Reports Server (NTRS)
Brown, N. E.; Dashner, T. R.; Hayes, B. C.
1973-01-01
A listing of astronaut EVA support systems and equipment, and the physical, operational, and performance characteristics of each major system are presented. An overview of the major ground based support operations necessary in the development and verification of orbital EVA systems is included. The performance and biomedical characteristics of man in the orbital EV environment are discussed. Major factors affecting astronaut EV work performance are identified and delineated as they relate to EV support systems design. Data concerning the medical and physiological aspects of spaceflight on man are included. The document concludes with an extensive bibliography, and a series of appendices which expand on some of the information presented in the main body.
Lead Toxicosis in a Southern Ground Hornbill Bucorvus leadbeateri in South Africa.
Koeppel, Katja N; Kemp, Lucy V
2015-12-01
The southern ground hornbill (Bucorvus leadbeateri) has been classified as globally vulnerable and, in South Africa, regionally endangered, with a negative population trend. Factors contributing to the population decline in South Africa are poisoning, electrocution, and illegal capture for trade, coupled with slow reproductive rates and extensive habitat requirements. Lead toxicosis is a previously undescribed threat for the population. An adult southern ground hornbill presented with acute lead toxicosis due to lead particles in the gizzard, which required intensive treatment. Two other hornbills were likely exposed. The source of the lead in these cases was likely a carcass of a porcupine that was killed with lead shot. This report highlights the importance of the use of lead-free ammunition within the habitat of the southern ground hornbill in South Africa.
Leake, S.A.; Galloway, D.L.
2007-01-01
A new computer program was developed to simulate vertical compaction in models of regional ground-water flow. The program simulates ground-water storage changes and compaction in discontinuous interbeds or in extensive confining units, accounting for stress-dependent changes in storage properties. The new program is a package for MODFLOW, the U.S. Geological Survey modular finite-difference ground-water flow model. Several features of the program make it useful for application in shallow, unconfined flow systems. Geostatic stress can be treated as a function of water-table elevation, and compaction is a function of computed changes in effective stress at the bottom of a model layer. Thickness of compressible sediments in an unconfined model layer can vary in proportion to saturated thickness.
Extensive degeneracy, Coulomb phase and magnetic monopoles in artificial square ice.
Perrin, Yann; Canals, Benjamin; Rougemaille, Nicolas
2016-12-15
Artificial spin-ice systems are lithographically patterned arrangements of interacting magnetic nanostructures that were introduced as way of investigating the effects of geometric frustration in a controlled manner. This approach has enabled unconventional states of matter to be visualized directly in real space, and has triggered research at the frontier between nanomagnetism, statistical thermodynamics and condensed matter physics. Despite efforts to create an artificial realization of the square-ice model-a two-dimensional geometrically frustrated spin-ice system defined on a square lattice-no simple geometry based on arrays of nanomagnets has successfully captured the macroscopically degenerate ground-state manifold of the model. Instead, square lattices of nanomagnets are characterized by a magnetically ordered ground state that consists of local loop configurations with alternating chirality. Here we show that all of the characteristics of the square-ice model are observed in an artificial square-ice system that consists of two sublattices of nanomagnets that are vertically separated by a small distance. The spin configurations we image after demagnetizing our arrays reveal unambiguous signatures of a Coulomb phase and algebraic spin-spin correlations, which are characterized by the presence of 'pinch' points in the associated magnetic structure factor. Local excitations-the classical analogues of magnetic monopoles-are free to evolve in an extensively degenerate, divergence-free vacuum. We thus provide a protocol that could be used to investigate collective magnetic phenomena, including Coulomb phases and the physics of ice-like materials.
NASA Technical Reports Server (NTRS)
Gatos, H. C.; Witt, A. F.; Lichtensteiger, M.; Herman, C. J.
1982-01-01
The crystal growth and segregation characteristics of a melt in a directional solidification configuration under near zero g conditions were investigated. The germanium (doped with gallium) system was selected because it was extensively studied on Earth and because it lends itself to a very detailed macroscopic and microscopic characterization. An extensive study was performed of the germanium crystals grown during the Apollo-Soyuz Test Project mission. It was found that single crystal growth was achieved and that the interface demarcation functioned successfully. On the basis of the results obtained to date, there is no indication that convection driven by thermal or surface tension gradients was present in the melt. The gallium segregation, in the absence of gravity, was found to be fundamentally different in its initial and its subsequent stages from that of the ground based tests. None of the existing theoretical models for growth and segregation can account for the observed segregation behavior in the absence of gravity.
Model Checking Degrees of Belief in a System of Agents
NASA Technical Reports Server (NTRS)
Raimondi, Franco; Primero, Giuseppe; Rungta, Neha
2014-01-01
Reasoning about degrees of belief has been investigated in the past by a number of authors and has a number of practical applications in real life. In this paper we present a unified framework to model and verify degrees of belief in a system of agents. In particular, we describe an extension of the temporal-epistemic logic CTLK and we introduce a semantics based on interpreted systems for this extension. In this way, degrees of beliefs do not need to be provided externally, but can be derived automatically from the possible executions of the system, thereby providing a computationally grounded formalism. We leverage the semantics to (a) construct a model checking algorithm, (b) investigate its complexity, (c) provide a Java implementation of the model checking algorithm, and (d) evaluate our approach using the standard benchmark of the dining cryptographers. Finally, we provide a detailed case study: using our framework and our implementation, we assess and verify the situational awareness of the pilot of Air France 447 flying in off-nominal conditions.
NASA Technical Reports Server (NTRS)
Cheung, Kar-Ming; Tung, Ramona H.; Lee, Charles H.
2003-01-01
In this paper, we describe the development roadmap and discuss the various challenges of an evolvable and extensible multi-mission telecom planning and analysis framework. Our long-term goal is to develop a set of powerful flexible telecommunications analysis tools that can be easily adapted to different missions while maintain the common Deep Space Communication requirements. The ability of re-using the DSN ground models and the common software utilities in our adaptations has contributed significantly to our development efforts measured in terms of consistency, accuracy, and minimal effort redundancy, which can translate into shorter development time and major cost savings for the individual missions. In our roadmap, we will address the design principles, technical achievements and the associated challenges for following telecom analysis tools (i) Telecom Forecaster Predictor - TFP (ii) Unified Telecom Predictor - UTP (iii) Generalized Telecom Predictor - GTP (iv) Generic TFP (v) Web-based TFP (vi) Application Program Interface - API (vii) Mars Relay Network Planning Tool - MRNPT.
Assessing background ground water chemistry beneath a new unsewered subdivision
Wilcox, J.D.; Bradbury, K.R.; Thomas, C.L.; Bahr, J.M.
2005-01-01
Previous site-specific studies designed to assess the impacts of unsewered subdivisions on ground water quality have relied on upgradient monitoring wells or very limited background data to characterize conditions prior to development. In this study, an extensive monitoring program was designed to document ground water conditions prior to construction of a rural subdivision in south-central Wisconsin. Previous agricultural land use has impacted ground water quality; concentrations of chloride, nitrate-nitrogen, and atrazine ranged from below the level of detection to 296 mg/L, 36 mg/L, and 0.8 ??g/L, respectively, and were highly variable from well to well and through time. Seasonal variations in recharge, surface topography, aquifer heterogeneities, surficial loading patterns, and well casing depth explain observed variations in ground water chemistry. This variability would not have been detected if background conditions were determined from only a few monitoring wells or inferred from wells located upgradient of the subdivision site. This project demonstrates the importance of characterizing both ground water quality and chemical variability prior to land-use change to detect any changes once homes are constructed. Copyright ?? 2005 National Ground Water Association.
From Regional Hazard Assessment to Nuclear-Test-Ban Treaty Support - InSAR Ground Motion Services
NASA Astrophysics Data System (ADS)
Lege, T.; Kalia, A.; Gruenberg, I.; Frei, M.
2016-12-01
There are numerous scientific applications of InSAR methods in tectonics, earthquake analysis and other geologic and geophysical fields. Ground motion on local and regional scale measured and monitored via the application of the InSAR techniques provide scientists and engineers with plenty of new insights and further understanding of subsurface processes. However, the operational use of InSAR is not yet very widespread. To foster the operational utilization of the Copernicus Sentinel Satellites in the day-to-day business of federal, state and municipal work and planning BGR (Federal Institute for Geosciences and Natural Resources) initiated workshops with potential user groups. Through extensive reconcilement of interests and demands with scientific, technical, economic and governmental stakeholders (e.g. Ministries, Mining Authorities, Geological Surveys, Geodetic Surveys and Environmental Agencies on federal and state level, SMEs, German Aerospace Center) BGR developed the concept of the InSAR based German National Ground Motion Service. One important backbone for the nationwide ground motion service is the so-called Persistent Scatterer Interferometry Wide Area Product (WAP) approach developed with grants of European research funds. The presentation shows the implementation of the ground motion service and examples for product developments for operational supervision of mining, water resources management and spatial planning. Furthermore the contributions of Copernicus Sentinel 1 radar data in the context of CTBT are discussed. The DInSAR processing of Sentinel 1 IW (Interferometric Wide Swath) SAR acquisitions from January 1st and 13th Jan. 2016 allow for the first time a near real time ground motion measurement of the North Korean nuclear test site. The measured ground displacements show a strong spatio-temporal correlation to the calculated epicenter measured by teleseismic stations. We are convinced this way another space technique will soon contribute even further to secure better societal information needs.
NASA Astrophysics Data System (ADS)
Saracco, Ginette; Moreau, Frédérique; Mathé, Pierre-Etienne; Hermitte, Daniel; Michel, Jean-Marie
2007-10-01
We have previously developed a method for characterizing and localizing `homogeneous' buried sources, from the measure of potential anomalies at a fixed height above ground (magnetic, electric and gravity). This method is based on potential theory and uses the properties of the Poisson kernel (real by definition) and the continuous wavelet theory. Here, we relax the assumption on sources and introduce a method that we call the `multiscale tomography'. Our approach is based on the harmonic extension of the observed magnetic field to produce a complex source by use of a complex Poisson kernel solution of the Laplace equation for complex potential field. A phase and modulus are defined. We show that the phase provides additional information on the total magnetic inclination and the structure of sources, while the modulus allows us to characterize its spatial location, depth and `effective degree'. This method is compared to the `complex dipolar tomography', extension of the Patella method that we previously developed. We applied both methods and a classical electrical resistivity tomography to detect and localize buried archaeological structures like antique ovens from magnetic measurements on the Fox-Amphoux site (France). The estimates are then compared with the results of excavations.
A massive pulsar in a compact relativistic binary.
Antoniadis, John; Freire, Paulo C C; Wex, Norbert; Tauris, Thomas M; Lynch, Ryan S; van Kerkwijk, Marten H; Kramer, Michael; Bassa, Cees; Dhillon, Vik S; Driebe, Thomas; Hessels, Jason W T; Kaspi, Victoria M; Kondratiev, Vladislav I; Langer, Norbert; Marsh, Thomas R; McLaughlin, Maura A; Pennucci, Timothy T; Ransom, Scott M; Stairs, Ingrid H; van Leeuwen, Joeri; Verbiest, Joris P W; Whelan, David G
2013-04-26
Many physically motivated extensions to general relativity (GR) predict substantial deviations in the properties of spacetime surrounding massive neutron stars. We report the measurement of a 2.01 ± 0.04 solar mass (M⊙) pulsar in a 2.46-hour orbit with a 0.172 ± 0.003 M⊙ white dwarf. The high pulsar mass and the compact orbit make this system a sensitive laboratory of a previously untested strong-field gravity regime. Thus far, the observed orbital decay agrees with GR, supporting its validity even for the extreme conditions present in the system. The resulting constraints on deviations support the use of GR-based templates for ground-based gravitational wave detectors. Additionally, the system strengthens recent constraints on the properties of dense matter and provides insight to binary stellar astrophysics and pulsar recycling.
2011-05-01
execute it. Because of its high importance it gets covered in management school extensively. Despite its high importance and extensive coverage, many...with a single criterion that they employ a large number of people. A key finding from the survey was that none of the participating agencies had any...personnel management without regard to political affiliation, race, color, religion, national origin, sex , marital status, age, or handicapping
Chemical quality of ground water in the eastern Sacramento Valley, California
Fogelman, Ronald P.
1979-01-01
The study area is about 1,300 square miles in the eastern Sacramento Valley, Calif., extending from the latitude of Roseville on the south to thelatitude of Chico on the north. Considering the increased agricultural development of the area, this report documents the chemical character of the ground water prior to water-level declines that could result from extensive pumping for irrigation or to changes caused by extensive use of imported surface water. Chemical analyses of samples from 222 wells show that most of the area is underlain by ground water of a quality suitable for most agricultural and domestic purposes. Ninety-five percent of the water sampled has dissolved-solids concentrations of less than 700 milligrams per liter. The general water type for the area is a calcium and magnesium bicarbonate water and there are negligible amounts of toxic trace elements. The potential for water-quality problems exists in the area south of Yuba City along the west bank of the Feather River. There, concentrations of chloride, sulfate, and dissolved solids are higher than in other parts of the area, and they could limit future agricultural activities if chloride- and sulfate-sensitive crops are grown. (Woodard-USGS)
Economic and social activities on ancient Cypriot terraced landscapes.
Ridder, Elizabeth; Galletti, Christopher S; Fall, Patricia L; Falconer, Steven E
2017-11-01
We investigate ancient agricultural terraces and their associated social and economic activities across the site complex consisting of the village at Politiko-Troullia and its more extensive associated taskscape. Surface artifact distributions mapped over 12 ha are integrated with evidence excavated from this Bronze Age settlement in central Cyprus. Contrary to expectations, artifact densities do not diminish with distance from the village architecture. In particular, concentrations of Prehistoric Bronze Age ceramics and ground stone artifacts are most pronounced on nearby terraced hillsides. These terraces were not utilized for domestic structures, but for extensive processing of agricultural crops and copper ore. Bronze Age excavated plant remains indicate cultivation of olives, grapes and figs, with wood resources dominated by olive and pine. Larger, non-portable ground stones and gaming stones are associated with communal social and economic activities in open courtyard settings in Politiko-Troullia. This category of ground stone also is particularly common on the terraced hillsides around Troullia, suggesting that similar behaviors occurred beyond village structures. The terraced landscape of Politiko-Troullia exemplifies a multi-faceted taskscape with a range of agricultural, metallurgical and social activities. Copyright © 2016 Elsevier Ltd. All rights reserved.
Key Response Planning Factors for the Aftermath of Nuclear Terrorism
DOE Office of Scientific and Technical Information (OSTI.GOV)
Buddemeier, B R; Dillon, M B
Despite hundreds of above-ground nuclear tests and data gathered from Hiroshima and Nagasaki, the effects of a ground-level, low-yield nuclear detonation in a modern urban environment are still the subject of considerable scientific debate. Extensive review of nuclear weapon effects studies and discussions with nuclear weapon effects experts from various federal agencies, national laboratories, and technical organizations have identified key issues and bounded some of the unknowns required to support response planning for a low-yield, ground-level nuclear detonation in a modern U.S. city. This study, which is focused primarily upon the hazards posed by radioactive fallout, used detailed fallout predictionsmore » from the advanced suite of three-dimensional (3-D) meteorology and plume/fallout models developed at Lawrence Livermore National Laboratory (LLNL), including extensive global Key Response Planning Factors for the Aftermath of Nuclear Terrorism geographical and real-time meteorological databases to support model calculations. This 3-D modeling system provides detailed simulations that account for complex meteorology and terrain effects. The results of initial modeling and analysis were presented to federal, state, and local working groups to obtain critical, broad-based review and feedback on strategy and messaging. This effort involved a diverse set of communities, including New York City, National Capitol Regions, Charlotte, Houston, Portland, and Los Angeles. The largest potential for reducing casualties during the post-detonation response phase comes from reducing exposure to fallout radiation. This can be accomplished through early, adequate sheltering followed by informed, delayed evacuation.B The response challenges to a nuclear detonation must be solved through multiple approaches of public education, planning, and rapid response actions. Because the successful response will require extensive coordination of a large number of organizations, supplemented by appropriate responses by local responders and the general population within the hazard zones, regional planning is essential to success. The remainder of this Executive Summary provides summary guidance for response planning in three areas: (1) Public Protection Strategy details the importance of early, adequate shelter followed by informed evacuation. (2) Responder Priorities identify how to protect response personnel, perform regional situational assessment, and support public safety. (3) Key Planning Considerations refute common myths and provide important information on planning how to respond in the aftermath of nuclear terrorism.« less
Electrical-analog analysis of ground-water depletion in central Arizona
Anderson, T.W.
1968-01-01
The Salt River Valley and the lower Santa Cruz River basin are the two largest agricultural areas in Arizona. The extensive use of ground water for irrigation has resulted in the need for a thorough appraisal of the present and future ground-water resources. The ground-water reservoir provides 80 percent (3.2 million acre-feet) of the total annual water supply. The amount of water pumped greatly exceeds the rate at which the ground-water supply is being replenished and has resulted in water-level declines of as much as 20 feet per year in some places. The depletion problem is of economic importance because ground water will become more expensive as pumping lifts increase and well yields decrease. The use of electrical-analog modeling techniques has made it possible to predict future ground-water levels under conditions of continued withdrawal in excess of the rate of replenishment. The electrical system is a representation of the hydrologic system: resistors and capacitors represent transmissibility and storage coefficients. The analogy between the two systems is accepted when the data obtained from the model closely match the field data in this instance, measured water-level change since 1923. The prediction of future water-table conditions is accomplished by a simple extension of the pumping trends to determine the resultant effect on the regional water levels. The results of this study indicate the probable depths to water in central Arizona in 1974 and 1984 if the aquifer characteristics are accurately modeled and if withdrawal of ground water continues at the same rate and under the tame areal distribution as existed between 1958 and 1964. The greatest depths to water in 1984 will be more than 700 feet near Stanfield and more than 650 feet in Deer Valley and northeast of Gilbert. South of Eloy and northwest of Litchfield Park, a static water level of more than 550 feet is predicted. The total water-level decline in the 20-year period 1964-84 at the deepest points of the major cones of depression will range from 150 to 300 feet, and the average decline in the entire central Arizona area will be about 100 feet.
NASA Technical Reports Server (NTRS)
Henderson, R. G.; Thomas, G. S.; Nalepka, R. F.
1975-01-01
Methods of performing signature extension, using LANDSAT-1 data, are explored. The emphasis is on improving the performance and cost-effectiveness of large area wheat surveys. Two methods were developed: ASC, and MASC. Two methods, Ratio, and RADIFF, previously used with aircraft data were adapted to and tested on LANDSAT-1 data. An investigation into the sources and nature of between scene data variations was included. Initial investigations into the selection of training fields without in situ ground truth were undertaken.
Kinetic measurements of gait for osteoarthritis research in dogs and cats
Moreau, Maxim; Lussier, Bertrand; Ballaz, Laurent; Troncy, Eric
2014-01-01
Over the past 2 decades the measurement of ground reaction forces (GRF) has been extensively used in dogs and cats to gain insights on normal locomotion, discrepancies under pathologic conditions, and biomechanical changes following surgical procedures. Ground reaction forces have become a well-established outcome measure of pain-related functional impairment in animals affected by experimental and naturally occurring osteoarthritis. This paper comprehensively reviews the nature of GRF and presents arguments regarding its measurement in osteoarthritis research. PMID:25392548
The ground state of the Frenkel-Kontorova model
NASA Astrophysics Data System (ADS)
Babushkin, A. Yu.; Abkaryan, A. K.; Dobronets, B. S.; Krasikov, V. S.; Filonov, A. N.
2016-09-01
The continual approximation of the ground state of the discrete Frenkel-Kontorova model is tested using a symmetric algorithm of numerical simulation. A "kaleidoscope effect" is found, which means that the curves representing the dependences of the relative extension of an N-atom chain vary periodically with increasing N. Stairs of structural transitions for N ≫ 1 are analyzed by the channel selection method with the approximation N = ∞. Images of commensurable and incommensurable structures are constructed. The commensurable-incommensurable phase transitions are stepwise.
NASA Astrophysics Data System (ADS)
Yang, Y.; Sciacchitano, A.; Veldhuis, L. L. M.; Eitelberg, G.
2016-10-01
During the ground operation of aircraft, there is potentially a system of vortices generated from the ground toward the propulsor, commonly denoted as ground vortices. Although extensive research has been conducted on ground vortices induced by turbofans which were simplified by suction tubes, these studies cannot well capture the properties of ground vortices induced by propellers, e.g., the flow phenomena due to intermittent characteristics of blade passing and the presence of slipstream of the propeller. Therefore, the investigation of ground vortices induced by a propeller is performed to improve understanding of these phenomena. The distributions of velocities in two different planes containing the vortices were measured by high frequency Particle Image Velocimetry. These planes are a wall-parallel plane in close proximity to the ground and a wall-normal plane upstream of the propeller. The instantaneous flow fields feature highly unsteady flow in both of these two planes. The spectral analysis is conducted in these two flow fields and the energetic frequencies are quantified. The flow fields are further evaluated by applying the Proper Orthogonal Decomposition analysis to capture the coherent flow structures. Consistent flow structures with strong contributions to the turbulent kinetic energy are noticed in the two planes.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Delfanti, Lavinia; Colantoni, Andrea, E-mail: colantoni@unitus.it; Recanatesi, Fabio
Photovoltaic plants developed on rural land are becoming a common infrastructure in the Mediterranean region and may contribute, at least indirectly, to various forms of environmental degradation including landscape deterioration, land take, soil degradation and loss in traditional cropland and biodiversity. Our study illustrates a procedure estimating (i) the extension of ground-mounted photovoltaic fields at the municipal scale in Italy and (ii) inferring the socioeconomic profile of the Italian municipalities experiencing different expansion rates of ground-mounted photovoltaic fields over the last years (2007-2014). The procedure was based on diachronic information derived from official data sources integrated into a geographical decisionmore » support system. Our results indicate that the surface area of ground-mounted photovoltaic fields into rural land grew continuously in Italy between 2007 and 2014 with positive and increasing growth rates observed during 2007-2011 and positive but slightly decreasing growth rates over 2012-2014, as a result of market saturation and policies containing the diffusion of solar plants on greenfields. We found important differences in the density of ground-mounted solar plants between northern and southern Italian municipalities. We identified accessible rural municipalities in southern Italy with intermediate population density and large availability of non-urban land as the most exposed to the diffusion of solar plants on greenfields in the last decade. Our approach is a promising tool to estimate changes in the use of land driven by the expansion of photovoltaic fields into rural land.« less
NASA Astrophysics Data System (ADS)
Hirtl, Marcus; Mantovani, Simone; Krüger, Bernd C.; Triebnig, Gerhard; Flandorfer, Claudia
2013-04-01
Air quality is a key element for the well-being and quality of life of European citizens. Air pollution measurements and modeling tools are essential for assessment of air quality according to EU legislation. The responsibilities of ZAMG as the national weather service of Austria include the support of the federal states and the public in questions connected to the protection of the environment in the frame of advisory and counseling services as well as expert opinions. The Air Quality model for Austria (AQA) is operated at ZAMG in cooperation with the University of Natural Resources and Life Sciences in Vienna (BOKU) by order of the regional governments since 2005. AQA conducts daily forecasts of gaseous and particulate (PM10) air pollutants over Austria. In the frame of the project AQA-PM (funded by FFG), satellite measurements of the Aerosol Optical Thickness (AOT) and ground-based PM10-measurements are combined to highly-resolved initial fields using regression- and assimilation techniques. For the model simulations WRF/Chem is used with a resolution of 3 km over the alpine region. Interfaces have been developed to account for the different measurements as input data. The available local emission inventories provided by the different Austrian regional governments were harmonized and used for the model simulations. An episode in February 2010 is chosen for the model evaluation. During that month exceedances of PM10-thresholds occurred at many measurement stations of the Austrian network. Different model runs (only model/only ground stations assimilated/satellite and ground stations assimilated) are compared to the respective measurements. The goal of this project is to improve the PM10-forecasts for Austria with the integration of satellite based measurements and to provide a comprehensive product-platform.
Preliminary results from the MAESTRO 1 Campaign over the Black Forest
NASA Technical Reports Server (NTRS)
Churchill, P. N.; Degrandi, G.; Sieber, A. J.
1990-01-01
The Joint Research Center (JRC) Ispra and the European Space Agency (ESA) have co-sponsored the deployment of the National Aeronautics and Space Agency (NASA) and Jet Propulsion Laboratory (JPL), C-, L-, and P-band polarimetric synthetic aperture radar (SAR) in Europe in mid-August 1989. This deployment represents the first opportunity for European agencies and institutes to evaluate the current state of the art of multifrequency polarimetric imaging technology over European Test Sites. Of particular interest to the Joint Research Center (JRC) Ispra is the Black Forest Test Site at Freiburg in the Federal Republic of Germany. This Test Site incorporates the Villingen region of the Black Forest to the south-west of Germany. This paper reports upon the activities undertaken in preparation for the MAESTRO 1 Campaign in the Black Forest Test Site. In particular this paper reports upon the ground data collection campaign for the Freiburg Test Site where extensive and intensive ground data measurements were undertaken. These measurements were based upon standard ground data collection protocols developed for forestry by the JRC and utilized throughout Europe for the MAESTRO 1 Campaign. The paper then goes on to present preliminary results derived from the SAR data using the JRC-developed software for polarimetric data interpretation, POLTOOL.
NASA Astrophysics Data System (ADS)
Hubert, G.; Pazianotto, M. T.; Federico, C. A.
2016-12-01
This paper investigates seasonal cosmic ray-induced neutron variations measured over a long-term period (from 2011 to 2016) in both the high-altitude stations located in medium geomagnetic latitude and Antarctica (Pic-du-Midi and Concordia, respectively). To reinforce analysis, modeling based on ground albedo neutrons simulations of extensive air showers and the solar modulation potential was performed. Because the local environment is well known and stable over time in Antarctica, data were used to validate the modeling approach. A modeled scene representative to the Pic-du-Midi was simulated with GEANT4 for various hydrogen properties (composition, density, and wet level) and snow thickness. The orders of magnitudes of calculated thermal fluence rates are consistent with measurements obtained during summers and winters. These variations are dominant in the thermal domain (i.e., En < 0.5 eV) and lesser degree in epithermal and evaporation domains (i.e., 0.5 eV < En < 0.1 MeV and 0.1 MeV < En < 20 MeV, respectively). Cascade neutron (En > 20 MeV) is weakly impacted. The role of hydrogen content on ground albedo neutron generation was investigated with GEANT4 simulations. These investigations focused to mountain environment; nevertheless, they demonstrate the complexity of the local influences on neutron fluence rates.
Butler, Robert J; Dai, Boyi; Huffman, Nikki; Garrett, William E; Queen, Robin M
2016-09-01
To examine how landing mechanics change in patients after anterior cruciate ligament reconstruction (ACL-R) between 6 months and 12 months after surgery. Case-series. Laboratory. Fifteen adolescent patients after ACL-R participated. Lower extremity three-dimensional motion analysis was conducted during a bilateral stop jump task in patients at 6 and 12 months after ACL-R. Joint kinematic and kinetic data, in addition to ground reaction forces, were collected at each time point. During the stop jump landing, the peak joint moments and the initial and peak joint motion at the ankle, knee, and hip were examined. The peak vertical ground reaction force was also examined. Interactions were observed for both the peak knee (P = 0.03) and hip extension moment (P = 0.07). However, only the hip extension moment was symmetrical level at 12 months. Statistically significant (P < 0.05) side-to-side differences existed for the ankle angle at initial contact, peak plantarflexion moment, peak hip flexion angle, and peak impact vertical ground reaction force independent of time. The findings of this study suggest that sagittal plane moments at the knee and hip demonstrate an increase in symmetry between 6 months and 1 year after ACL-R surgery, however, symmetry of the knee extension moment is not established by 12 months after surgery. The lack of change in the variables across time was unexpected. As a result, it is inappropriate to expect a change in landing mechanics solely as a result of time alone after discharge from rehabilitation.
Bennett, Victoria A.; Doerr, Veronica A. J.; Doerr, Erik D.; Manning, Adrian D.; Lindenmayer, David B.; Yoon, Hwan-Jin
2012-01-01
It is essential to choose suitable habitat when reintroducing a species into its former range. Habitat quality may influence an individual’s dispersal decisions and also ultimately where they choose to settle. We examined whether variation in habitat quality (quantified by the level of ground vegetation cover and the installation of nest boxes) influenced the movement, habitat choice and survival of a reintroduced bird species. We experimentally reintroduced seven social groups (43 individuals) of the brown treecreeper (Climacteris picumnus) into two nature reserves in south-eastern Australia. We radio-tracked 18 brown treecreepers from release in November 2009 until February 2010. We observed extensive movements by individuals irrespective of the release environment or an individual’s gender. This indicated that individuals were capable of dispersing and actively selecting optimum habitat. This may alleviate pressure on wildlife planners to accurately select the most optimum release sites, so long as the species’ requirements are met. There was significant variation in movement between social groups, suggesting that social factors may be a more important influence on movement than habitat characteristics. We found a significant effect of ground vegetation cover on the likelihood of settlement by social groups, with high rates of settlement and survival in dry forests, rather than woodland (where the species typically resides), which has implications for the success of woodland restoration. However, overall the effects of variation in habitat quality were not as strong as we had expected, and resulted in some unpredicted effects such as low survival and settlement in woodland areas with medium levels of ground vegetation cover. The extensive movement by individuals and unforeseen effects of habitat characteristics make it difficult to predict the outcome of reintroductions, the movement behaviour and habitat selection of reintroduced individuals, particularly when based on current knowledge of a species’ ecology. PMID:23227192
NASA Astrophysics Data System (ADS)
Bishop, R. L.; Coster, A. J.; Turner, D. L.; Nikoukar, R.; Lemon, C.; Bust, G. S.; Roeder, J. L.
2016-12-01
Earth's plasmasphere is a region of cold (T ≤ 1 eV), dense (n 101 to 104 cm-3) plasma located in the inner magnetosphere and coincident with a portion of the ionosphere that co-rotates with the planet in the geomagnetic field. Plasmaspheric plasma originates in the ionosphere and fills the magnetic flux tubes on which the corotation electric field dominates over the convection electric field. The corotation electric field results from Earth's spinning magnetic field while the convection electric field results from the solar wind driving of global plasma convection within the magnetosphere. The outer boundary of the plasmasphere is the plasmapause, and it corresponds to the transition region between corotation-driven vs. convection-driven plasmas. During quiet periods of low solar wind speed and weak interplanetary magnetic field (IMF), ionospheric outflow from lower altitudes can fill the plasmasphere over the course of several days with the plasmapause expanding to higher L-shells. However, when the convection electric field is enhanced during active solar wind periods, such as magnetic storms, the plasmasphere can be rapidly eroded to L 2.5 or less leading to many interesting magnetospheric and ionospheric features such as plasmapause erosion, plasmaspheric plumes and ionospheric plasma outflows. In this presentation, we focus on the dynamics of the plasmapause as observed by ground-based and space-borne GPS receivers. We will focus on the period 15 March to 19 March 2013, which includes the on-set and recovery periods of a strong geomagnetic storm. We will examine the location and erosion time scales of the plasmapause during the active portion of the storm. An extensive global network of ground-based scientific receivers ( 4000) will be utilized in the study. Space-based observations will be obtained from data from the CORISS GPS radio occultation (RO) sensor on the C/NOFS satellite as well as the COSMIC GPS RO sensors.
Escobar-Rodríguez, Tomás; Romero-Alonso, María Mercedes
2013-05-01
This article analyzes the attitude of nurses toward the use of automated unit-based medication storage and distribution systems and identifies influencing factors. Understanding these factors provides an opportunity to explore actions that might be taken to boost adoption by potential users. The theoretical grounding for this research is the Technology Acceptance Model. The Technology Acceptance Model specifies the causal relationships between perceived usefulness, perceived ease of use, attitude toward using, and actual usage behavior. The research model has six constructs, and nine hypotheses were generated from connections between these six constructs. These constructs include perceived risks, experience level, and training. The findings indicate that these three external variables are related to the perceived ease of use and perceived usefulness of automated unit-based medication storage and distribution systems, and therefore, they have a significant influence on attitude toward the use of these systems.
On-irrigator pasture soil moisture sensor
NASA Astrophysics Data System (ADS)
Eng-Choon Tan, Adrian; Richards, Sean; Platt, Ian; Woodhead, Ian
2017-02-01
In this paper, we presented the development of a proximal soil moisture sensor that measured the soil moisture content of dairy pasture directly from the boom of an irrigator. The proposed sensor was capable of soil moisture measurements at an accuracy of ±5% volumetric moisture content, and at meter scale ground area resolutions. The sensor adopted techniques from the ultra-wideband radar to enable measurements of ground reflection at resolutions that are smaller than the antenna beamwidth of the sensor. An experimental prototype was developed for field measurements. Extensive field measurements using the developed prototype were conducted on grass pasture at different ground conditions to validate the accuracy of the sensor in performing soil moisture measurements.
Comparing On-Orbit and Ground Performance for an S-Band Software-Defined Radio
NASA Technical Reports Server (NTRS)
Chelmins, David T.; Welch, Bryan W.
2014-01-01
NASA's Space Communications and Navigation Testbed was installed on an external truss of the International Space Station in 2012. The testbed contains several software-defined radios (SDRs), including the Jet Propulsion Laboratory (JPL) SDR, which underwent performance testing throughout 2013 with NASAs Tracking and Data Relay Satellite System (TDRSS). On-orbit testing of the JPL SDR was conducted at S-band with the Glenn Goddard TDRSS waveform and compared against an extensive dataset collected on the ground prior to launch. This paper will focus on the development of a waveform power estimator on the ground post-launch and discuss the performance challenges associated with operating the power estimator in space.
Comparing On-Orbit and Ground Performance for an S-Band Software-Defined Radio
NASA Technical Reports Server (NTRS)
Chelmins, David; Welch, Bryan
2014-01-01
NASA's Space Communications and Navigation Testbed was installed on an external truss of the International Space Station in 2012. The testbed contains several software-defined radios (SDRs), including the Jet Propulsion Laboratory (JPL) SDR, which underwent performance testing throughout 2013 with NASA's Tracking and Data Relay Satellite System (TDRSS). On-orbit testing of the JPL SDR was conducted at S-band with the Glenn Goddard TDRSS waveform and compared against an extensive dataset collected on the ground prior to launch. This paper will focus on the development of a waveform power estimator on the ground post-launch and discuss the performance challenges associated with operating the power estimator in space.
Hydrogeology of the surficial aquifer system, Dade County, Florida
Fish, J.E.; Stewart, M.T.
1991-01-01
An investigation of the surficial aquifer system in Dade County, begun in 1983, is part of a regional study of the aquifer system in southeastern Florida. Test drilling for lithologic samples, flow measurements during drilling, aquifer testing, and analyses of earlier data permitted delineation of the hydraulic conductivity distribution (on hydrogeologic sections), the aquifers in the system, the generalized transmissivity distribution, and interpretation of the ground-water flow system. The surficial aquifer system, in which an unconfined ground-water flow system exists, is composed of the sediments from land surface downward to the top of a regionally extensive zone of sediments of low permeability called the intermediate confining unit. The aquifer system units, which vary in composition from clay-size sediments to cavernous limestone, are hydro stratigraphically divided into the Biscayne aquifer at the top; an intervening semiconfining unit that consists principally of clayey sand; a predominantly gray limestone aquifer in the Tamiami Formation in western and west-central Dade County; and sand or clayey sand near the base of the surficial aquifer system. The base of the surficial aquifer system ranges from a depth of about 175 to 210 feet below land surface in westernmost Dade County to greater than 270 feet in northeastern Dade County. Test drilling and aquifer-test data indicate a complex hydraulic conductivity distribution. Hydraulic conductivities of the very highly permeable zone of the Biscayne aquifer commonly exceed 10,000 feet per day; in the gray limestone aquifer, they range from 210 to 780 feet per day. Transmissivities of the surficial aquifer system vary locally but have a recognizable areal trend. Estimated values generally are about 300,000 feet squared per day or greater in nearly all of central and eastern Dade County. Transmissivity is lower to the west, decreasing to less than 75,000 feet squared per day in western Dade County. High transmissivity usually is associated with thick sections of the Fort Thompson Formation within the Biscayne aquifer. The gray limestone aquifer of the Tamiami Formation has transmissivities that range from 5,800 to 39,000 feet squared per day in western Dade County. The transition from high transmissivity to relatively low transmissivity is often only a few miles wide and coincides with the decrease in thickness of the very highly permeable Fort Thompson Formation, which marks the western boundary of the Biscayne aquifer. More effective drainage as a result of extensive canal systems and large-scale pumping from municipal well fields has greatly altered the predevelopment flow system in eastern Dade County by: (1) eliminating or greatly reducing a seasonal and coastal ground-water ridge; (2) reducing deep circulation; (3) reducing or eliminating seasonal westward movement of ground water; (4) causing accelerated stormwater runoff and short ground-water flow paths; and (5) generally lowering the water table and inducing saltwater intrusion. Under predevelopment conditions in western Dade County, water entered the gray limestone aquifer by lateral movement from Broward and Collier Counties, and by downward seepage from The Everglades and the Biscayne aquifer, and moved southward and southeastward into Dade County to coastal discharge areas. Circulation in the Biscayne aquifer inland also was primarily to the south and southeast. In eastern Dade County, the seasonal ground-water ridge that formed under predevelopment conditions supported both easterly and westerly ground-water flow away from the ridge axis. This seasonal flow created a zone of lower dissolved solids.
Nanosponge Carriers- An Archetype Swing in Cancer Therapy: A Comprehensive Review.
Osmani, Riyaz Ali M; Hani, Umme; Bhosale, Rohit R; Kulkarni, Parthasarathi K; Shanmuganathan, Seetharaman
2017-01-01
Nanotechnology and nanomedicines are emerging research meadows; which chiefly focuses on creating and manipulating materials at a nanometer level for the betterment in imaging, diagnosis and treatment of a range of diseases together with cancer. Cyclodextrin-based nanosponges, anticipated as a new-fangled nanosized delivery system, are ground-breaking hyper-crosslinked cyclodextrin polymers nanostructured within a three-dimensional network. Nanosponges based systems hold the potential of elevating the solubility, absorption, penetration, bioavailability, in vivo stability, targeted as well as sustained delivery, and therapeutic efficiency of numerous anticancer agents. The extension of nanosponges based drug delivery systems is an exhilarating and demanding research pasture, predominantly to overcome aforementioned problems allied to existing anticancer formulations and for the further progressions in cancer therapies. Nanosponges in cancer therapy, particularly cyclodextrin based nanosponges are brought up in this review. By quoting diverse attempts made in pertinent direction, efforts have been made to exemplify the characteristics, suitability and versatility of cyclodextrin based nanosponges for their promising applications in cancer treatment.
NASA Astrophysics Data System (ADS)
Günther, Andreas; Aziz Patwary, Mohammad Abdul; Bahls, Rebecca; Asaduzzaman, Atm; Ludwig, Rüdiger; Ashraful Kamal, Mohammad; Nahar Faruqa, Nurun; Jabeen, Sarwat
2016-04-01
Dhaka Metropolitan City (including Dhaka and five adjacent municipal areas) is one of the fastest developing urban regions in the world. Densely build-up areas in the developed metropolitan area of Dhaka City are subject to extensive restructuring as common six- or lower storied buildings are replaced by higher and heavier constructions. Additional stories are built on existing houses, frequently exceeding the allowable bearing pressure on the subsoil as supported by the foundations. In turn, newly developing city areas are projected in marshy terrains modified by extensive, largely unengineered landfills. In most areas, these terrains bear unfavorable building ground conditions within 30 meters. Within a collaborative technical cooperation project between Bangladesh and Germany, BGR supports GSB in the provision of geo-information for the Capital Development Authority (RAJUK). For general urban planning, RAJUK successively develops a detailed area plan (DAP) at scale 1 : 50000 for the whole Dhaka Metropolitan City area (approx. 1700 km2). Geo-information have not been considered in the present DAP. Within the project, geospatial information in form of a geomorphic map, a digital terrain model and a 3-D subsurface model covering the whole city area have been generated at a scale of 1 : 50000. An extensive engineering geological data base consisting of more than 2200 borehole data with associated Standard Penetration Testing (SPT) and lab data has been compiled. With the field testing (SPT) and engineering geological lab data, the 3-D subsurface model can be parameterized to derive important spatial subsurface information for urban planning like bearing capacity evaluations for different foundation designs or soil liquefaction potential assessments for specific earthquake scenarios. In conjunction with inundation potential evaluations for different flooding scenarios, comprehensive building ground suitability information can be derived to support risk-sensitive urban planning in Dhaka Metropolitan City area at the DAP scale
Balloon Borne Infrasound Platforms for Remote Monitoring of Natural Hazards
NASA Astrophysics Data System (ADS)
Lees, J. M.; Bowman, D. C.
2016-12-01
In the last three years several NASA supported balloon launches were instrumented with infrasound sensors to monitor acoustic wavefields in the stratosphere. Such high altitude platforms may detect geoacoustic phenomena at much greater ranges than equivalent ground stations, and perhaps record sound waves that rarely reach the Earth's surface. Since acoustic waves are a key diagnostic for several natural hazards (volcanic eruptions, severe storms, and tsunamis, for example), the increased range and spatial coverage of balloon borne arrays promise greater quantification and perhaps early warning of such events. Before this can be accomplished, the performance of stratospheric arrays must be compared to tthat of those on the ground. Here, we show evidence for 0.2 Hz infrasound associated with oceanic oscillations recorded during night time hours of the flights, consistent with concurrent ground recordings on the east and west coasts of North America. We also report numerous narrow band acoustic signals (5-30 Hz) that resemble recordings made in in the 1960's, the last time microphones were lofted into the stratosphere. Theoretical and ground based observational data from Rind(1977) indicate loss of acoustic energy in the thermosphere, where heating of the upper atmosphere is predicted to be on the order of 30-40 degrees Kelvin per day. We propose testing these ideas by using extensive ground arrays recently deployed in North America in conjunction with airborne platforms installed in the mid-stratosphere. New experiments scheduled for 2016 include circumnavigation of Antarctica (collected in June) as well as two proposed flights in New Mexico in September. The flights are designed to both capture known acoustic sources as well as events of opportunity.
Potential effects of recurrent low oxygen conditions on the Illinois Cave amphipod
Panno, S.V.; Hackley, Keith C.; Kelly, W.R.; Hwang, H.-H.; Wilhelm, F.M.; Taylor, S.J.; Stiff, B.J.
2006-01-01
The caves of Illinois' sinkhole plain are the sole habitat of the Illinois Cave amphipod (Gammarus acherondytes), a federally endangered species. The sinkhole plain is a hydrologically-connected sequence of karstified limestone that constitutes an extensive karst aquifer which serves as an important source of potable water for area residents. During this investigation, we examined the ground-water quality in caves within two ground-water basins: 1) Illinois Caverns, where the amphipod is now present after previously reported to have been extirpated from the lower reaches, and 2) Stemler Cave, where the amphipod is reported to have been extirpated. The chemical composition of cave streams in Illinois Caverns and Stemler Cave were compared to determine which parameters, if any, could have contributed to the loss of G. acherondytes from Stemler Cave. Stream water in Stemler Cave contained higher concentrations of organic carbon, potassium, silica, chloride, fluoride, sulfate, iron and manganese than Illinois Caverns. Perhaps most importantly, dissolved oxygen (DO) concentrations in Stemler Cave were, during periods of low flow, substantially lower than in Illinois Caverns. Based on land use, there are probably at least eight times more private septic systems in the Stemler Cave ground-water basin than in the Illinois Caverns ground-water basin. Low DO concentrations were likely the result of microbial breakdown of soil organic matter and wastewater treatment system effluent, and the oxidation of pyrite in bedrock. The near-hypoxic DO in Stemler Cave that occurred during low-flow conditions, and, we speculate, a limited range of G. acherondytes within the Stemler Cave ground-water basin due to a metabolic advantage of the stygophilic aquatic invertebrates over the stygobitic G. acherodytes, resulted in the apparent loss of G. acherondytes from Stemler Cave.
Sepulveda, S.A.; Murphy, W.; Jibson, R.W.; Petley, D.N.
2005-01-01
The 1994 Northridge earthquake (Mw = 6.7) triggered extensive rock slope failures in Pacoima Canyon, immediately north of Los Angeles, California. Pacoima Canyon is a narrow and steep canyon incised in gneissic and granitic rocks. Peak accelerations of nearly 1.6 g were recorded at a ridge that forms the left abutment of Pacoima Dam; peak accelerations at the bottom of the canyon were less than 0.5 g, suggesting the occurrence of topographic amplification. Topographic effects have been previously suggested to explain similarly high ground motions at the site during the 1971 (Mw = 6.7) San Fernando earthquake. Furthermore, high landslide concentrations observed in the area have been attributed to unusually strong ground motions rather than higher susceptibility to sliding compared with nearby zones. We conducted field investigations and slope stability back-analyses to confirm the impact of topographic amplification on the triggering of landslides during the 1994 earthquake. Our results suggest that the observed extensive rock sliding and falling would have not been possible under unamplified seismic conditions, which would have generated a significantly lower number of areas affected by landslides. In contrast, modelling slope stability using amplified ground shaking predicts slope failure distributions matching what occurred in 1994. This observation confirms a significant role for topographic amplification on the triggering of landslides at the site, and emphasises the need to select carefully the inputs for seismic slope stability analyses. ?? 2005 Elsevier B.V. All rights reserved.
NASA Astrophysics Data System (ADS)
Wendisch, Manfred; Pöschl, Ulrich; Andreae, Meinrat O.; Machado, Luiz A. T.; Albrecht, Rachel; Schlager, Hans; Rosenfeld, Daniel; Krämer, Martina
2015-04-01
An extensive airborne/ground-based measurement campaign to study tropical convective clouds is introduced. It was performed in Brazil with focus on the Amazon rainforest from 1 September to 4 October 2014. The project combined the joint German-Brazilian ACRIDICON (Aerosol, Cloud, Precipitation, and Radiation Interactions and Dynamics of Convective Cloud Systems) and CHUVA (Machado et al.2014) projects. ACRIDICON aimed at the quantification of aerosol-cloud-precipitation interactions and their thermodynamic, dynamic and radiative effects in convective cloud systems by in-situ aircraft observations and indirect measurements (aircraft, satellite, and ground-based). The ACRIDICON-CHUVA campaign was conducted in cooperation with the second Intensive Operational Phase (IOP) of the GOAmazon (Green Ocean Amazon) program. The focus in this presentation is on the airborne observations within ACRIDICON-CHUVA. The German HALO (High Altitude and Long-Range Research Aircraft) was based in Manaus (Amazonas State); it carried out 14 research flights (96 flight hours in total). HALO was equipped with remote sensing and in-situ instrumentation for meteorological, trace gas, aerosol, cloud, and precipitation measurements. Five mission objectives were pursued: (1) cloud vertical evolution (cloud profiling), (2) aerosol processing (inflow and outflow), (3) satellite validation, (4) vertical transport and mixing (tracer experiment), and (5) clouds over forested and deforested areas. The five cloud missions collected data in clean atmospheric conditions and in contrasting polluted (urban and biomass burning) environments.
NASA Technical Reports Server (NTRS)
Goroshin, Sam; Kolbe, Massimilliano; Bellerose, Julie; Lee, John
2003-01-01
Due to particle sedimentation and relatively low laminar flame speeds in dust suspensions, microgravity environment is essential for the observation of laminar dust flames in a wide range of particle sizes and fuel concentrations [1]. The capability of a reduced-gravity environment to facilitate study of dust combustion was realized by researchers long before current microgravity programs were established by the various national Space Agencies. Thus, several experimentalists even built their own, albeit very short-duration, drop tower facilities to study flames in particle and droplet suspensions [2,3]. About ten years ago, authors of the present paper started their dust combustion reduced gravity research with the investigation of the constant volume dust flames in a spherical-bomb on board a parabolic flight aircraft [4]. However it was soon realized that direct observation of the constant-pressure flame might be more beneficial. Thus, microgravity apparatus, permitting examination of the freely propagating flames in open-end tubes, was tested in parabolic flights three years later [5]. The improved design of the newlyconstructed apparatus for the experiments on board the NASA KC-135 aircraft is also based on the observation of the dust flame propagating in semi-opened tubes with free expansion of the combustion products that are continuously vented overboard. The apparatus design and results of its extensive ground-based testing are presented below.
Advanced Diagnostic System on Earth Observing One
NASA Technical Reports Server (NTRS)
Hayden, Sandra C.; Sweet, Adam J.; Christa, Scott E.; Tran, Daniel; Shulman, Seth
2004-01-01
In this infusion experiment, the Livingstone 2 (L2) model-based diagnosis engine, developed by the Computational Sciences division at NASA Ames Research Center, has been uploaded to the Earth Observing One (EO-1) satellite. L2 is integrated with the Autonomous Sciencecraft Experiment (ASE) which provides an on-board planning capability and a software bridge to the spacecraft's 1773 data bus. Using a model of the spacecraft subsystems, L2 predicts nominal state transitions initiated by control commands, monitors the spacecraft sensors, and, in the case of failure, isolates the fault based on the discrepant observations. Fault detection and isolation is done by determining a set of component modes, including most likely failures, which satisfy the current observations. All mode transitions and diagnoses are telemetered to the ground for analysis. The initial L2 model is scoped to EO-1's imaging instruments and solid state recorder. Diagnostic scenarios for EO-1's nominal imaging timeline are demonstrated by injecting simulated faults on-board the spacecraft. The solid state recorder stores the science images and also hosts: the experiment software. The main objective of the experiment is to mature the L2 technology to Technology Readiness Level (TRL) 7. Experiment results are presented, as well as a discussion of the challenging technical issues encountered. Future extensions may explore coordination with the planner, and model-based ground operations.
Survey of bridge decks with ground-penetration radar : a manual.
DOT National Transportation Integrated Search
1985-01-01
The report presents the findings of a study of the feasibility of locating audio-teleconferencing equipment in the residency offices of the Department. As an extension of a larger study documented in entry 11-45, teleconferencing units were installed...
DOE Office of Scientific and Technical Information (OSTI.GOV)
Not Available
1991-09-30
The 5-square-mile Sturgis Municipal Wells site is an active municipal well field in Sturgis, St. Joseph County, Michigan. Land use in the area is predominantly mixed industrial and residential, with several wetlands areas located near the site. The site includes the former Wade Electric facility, which closed in 1966 and burned down in 1974, and the Kirsch Company, which operated as a manufacturing facility until 1980. These two properties have been identified as two source areas responsible for the ground water contamination in the aquifer used for the municipal water supply. State investigations starting in 1982 identified contaminated soil andmore » VOC-contaminated ground water onsite and extensive ground water contamination in various wells throughout the city. The Record of Decision (ROD) addresses final remediation of soil and ground water. The primary contaminants of concern affecting the soil and ground water are VOCs including benzene, PCE, and TCE; and other organics including PAHs.« less
Experimental Insights into Ground-State Selection of Quantum XY Pyrochlores
NASA Astrophysics Data System (ADS)
Hallas, Alannah M.; Gaudet, Jonathan; Gaulin, Bruce D.
2018-03-01
Extensive experimental investigations of the magnetic structures and excitations in the XY pyrochlores have been carried out over the past decade. Three families of XY pyrochlores have emerged: Yb2B2O7, Er2B2O7, and, most recently, [Formula: see text]Co2F7. In each case, the magnetic cation (either Yb, Er, or Co) exhibits XY anisotropy within the local pyrochlore coordinates, a consequence of crystal field effects. Materials in these families display rich phase behavior and are candidates for exotic ground states, such as quantum spin ice, and exotic ground-state selection via order-by-disorder mechanisms. In this review, we present an experimental summary of the ground-state properties of the XY pyrochlores, including evidence that they are strongly influenced by phase competition. We empirically demonstrate the signatures for phase competition in a frustrated magnet: multiple heat capacity anomalies, suppressed TN or TC, sample- and pressure-dependent ground states, and unconventional spin dynamics.
Decoupling factors affecting plant diversity and cover on extensive green roofs.
MacIvor, J Scott; Margolis, Liat; Puncher, Curtis L; Carver Matthews, Benjamin J
2013-11-30
Supplemental irrigation systems are often specified on green roofs to ensure plant cover and growth, both important components of green roof performance and aesthetics. Properties of the growing media environment too can alter the assemblage of plant species able to thrive. In this study we determine how plant cover, above ground biomass and species diversity are influenced by irrigation and growing media. Grass and forb vegetative cover and biomass were significantly greater in organic based growing media but there was no effect of supplemental irrigation, with two warm season grasses dominating in those treatments receiving no supplemental irrigation. On the other hand, plant diversity declined without irrigation in organic media, and having no irrigation in inorganic growing media resulted in almost a complete loss of cover. Sedum biomass was less in inorganic growing media treatments and species dominance shifted when growing media organic content increased. Our results demonstrate that supplemental irrigation is required to maintain plant diversity on an extensive green roof, but not necessarily plant cover or biomass. These results provide evidence that planting extensive green roofs with a mix of plant species can ensure the survival of some species; maintaining cover and biomass when supplemental irrigation is turned off to conserve water, or during extreme drought. Crown Copyright © 2013. Published by Elsevier Ltd. All rights reserved.
Thomann, Matthew
2018-08-01
The global scale-up of AIDS treatment initiatives during the first decade of the twenty-first century has been referred to as a kind of 'pharmaceuticalisation' of public health, a trend that is now building in the area of HIV prevention. This paper traces the emergence and increased uptake of pre-exposure prophylaxis (PrEP), antiretroviral medications that can keep HIV negative individuals from becoming infected, placing it within the broader (re)casting of HIV prevention as a medical and technological problem that has been central to the recent 'end of AIDS' discourse. While HIV prevention discourses have been grounded in a neoliberal calculus of individual responsibility since the late 1990s, PrEP constitutes a pharmaceutical extension of the responsibilised sexual subject. Central to this extension are the acknowledgment of one's risk and a willingness to take pre-emptive medical action to secure a future without HIV. For men who have sex with men, a population heavily targeted for biomedical interventions in the United States, PrEP marks a shift in moral discourses of what it means to be a responsible sexual subject. Characteristics of the pharmaceutical extension of the neoliberal sexual subject are explored through an examination of a New York City-based PrEP promotional campaign.
NASA Astrophysics Data System (ADS)
Taylor, Thomas E.; L'Ecuyer, Tristan; Slusser, James; Stephens, Graeme; Krotkov, Nick; Davis, John; Goering, Christian
2005-08-01
Extensive sensitivity and error characteristics of a recently developed optimal estimation retrieval algorithm which simultaneously determines aerosol optical depth (AOD), aerosol single scatter albedo (SSA) and total ozone column (TOC) from ultra-violet irradiances are described. The algorithm inverts measured diffuse and direct irradiances at 7 channels in the UV spectral range obtained from the United States Department of Agriculture's (USDA) UV-B Monitoring and Research Program's (UVMRP) network of 33 ground-based UV-MFRSR instruments to produce aerosol optical properties and TOC at all seven wavelengths. Sensitivity studies of the Tropospheric Ultra-violet/Visible (TUV) radiative transfer model performed for various operating modes (Delta-Eddington versus n-stream Discrete Ordinate) over domains of AOD, SSA, TOC, asymmetry parameter and surface albedo show that the solutions are well constrained. Realistic input error budgets and diagnostic and error outputs from the retrieval are analyzed to demonstrate the atmospheric conditions under which the retrieval provides useful and significant results. After optimizing the algorithm for the USDA site in Panther Junction, Texas the retrieval algorithm was run on a cloud screened set of irradiance measurements for the month of May 2003. Comparisons to independently derived AOD's are favorable with root mean square (RMS) differences of about 3% to 7% at 300nm and less than 1% at 368nm, on May 12 and 22, 2003. This retrieval method will be used to build an aerosol climatology and provide ground-truthing of satellite measurements by running it operationally on the USDA UV network database.
The cosmic-ray ground-level enhancement of 1989 September 29
DOE Office of Scientific and Technical Information (OSTI.GOV)
Moraal, H.; Caballero-Lopez, R. A.
2014-08-01
The ground-level enhancement (GLE) of 1989 September 29 is one of the largest of 71 solar energetic particle events observed by neutron monitors on Earth. It was smaller than the record-breaking GLE 5 of 1956 February 23, but by some measures it was larger than GLE 69 of 2005 January 20. It is also the most extensively studied of the 71 GLEs, and it was observed by more than 50 ground-based detectors in the worldwide network. This paper contains another study of the event, with the main difference from previous studies that all the existing observations are employed, instead ofmore » the usual selection of stations. An effort is made to represent all the information graphically. This reveals new insight in the event, mainly about its time profile. The main conclusion is that the event is the best example available of a 'classical' GLE that has a gradual increase toward peak intensity and does not contain two or more distinct peaks as inferred previously. It does, however, suggest that there were two acceleration or release mechanisms: a prompt, rapid one and a delayed, slower one. This conclusion is based on a detailed comparison with GLE 69 of 2005 January 20, which is the best-known example of a double-peaked event with a 'prompt' component. It is also found that the rigidity spectrum was probably softer than derived in several previous studies, and that the decay phase of the event reveals that the cosmic-ray diffusion coefficient in the neutron monitor range is proportional to rigidity.« less
Quiet Short-Haul Research Aircraft - A summary of flight research since 1981
NASA Technical Reports Server (NTRS)
Riddle, Dennis W.; Stevens, Victor C.; Eppel, Joseph C.
1988-01-01
The Quiet Short-Haul Research Aircraft (QSRA), designed for flight investigation into powered-lift terminal area operations, first flew in 1978 and has flown 600 hours since. This report summarizes QSRA research since 1981. Numerous aerodynamic flight experiments have been conducted including research with an advanced concept stability and control augmentation and pilot display system for category III instrument landings. An electromechanical actuator system was flown to assess performance and reliability. A second ground-based test was conducted to further evaluate circulation-control-wing/upper-surface-blowing performance. QSRA technology has been transferred through reports, guest pilot evaluations and airshow participation. QSRA future research thoughts and an extensive report bibliography are also presented.
Búsqueda de Sitios para CTA: Análisis de Datos Satelitales
NASA Astrophysics Data System (ADS)
Suárez, A. E.; Medina, M. C.; Romero, G. E.
The CTA Consortium has decided to implement a systematic search for sites for the Observatory. This search will be made in two different steps. The first one consists of a general determination of the possible sites on the basis of some very basic selection criteria, such as geographic latitude, altitude and extension of the flat area needed. For those sites passing these criteria, a more intensive characterization should be made, using available satellite data, together with existing ground or air-based measurements. In this work we compare the behavior of different sites analyzing the aerosol content and the total precipitable water vapor, measured by MODIS instrument. FULL TEXT IN SPANISH
Statistics of multi-look AIRSAR imagery: A comparison of theory with measurements
NASA Technical Reports Server (NTRS)
Lee, J. S.; Hoppel, K. W.; Mango, S. A.
1993-01-01
The intensity and amplitude statistics of SAR images, such as L-Band HH for SEASAT and SIR-B, and C-Band VV for ERS-1 have been extensively investigated for various terrain, ground cover and ocean surfaces. Less well-known are the statistics between multiple channels of polarimetric of interferometric SAR's, especially for the multi-look processed data. In this paper, we investigate the probability density functions (PDF's) of phase differences, the magnitude of complex products and the amplitude ratios, between polarization channels (i.e. HH, HV, and VV) using 1-look and 4-look AIRSAR polarimetric data. Measured histograms are compared with theoretical PDF's which were recently derived based on a complex Gaussian model.
Very high energy gamma ray extension of GRO observations
NASA Technical Reports Server (NTRS)
Weekes, Trevor C.
1992-01-01
This has been an exiciting year for high energy gamma-ray astronomy, both from space and from ground-based observatories. It has been a particularly active period for the Whipple Observatory gamma-ray group. In phase 1 of the Compton Gamma Ray Observatory (GRO), there has not been too much opportunity for overlapping observations with the Energetic Gamma Ray Experiment Telescope (EGRET) and the other GRO telescopes; however, significant progress was made in the development of data analysis techniques and in improving the sensitivity of the technique which will have direct application in correlative observations in phase 2. Progress made during the period 1 Jul. 1991 - 31 Dec. 1991 is presented.
Urban Agglomeration and Extension in Northern Coast of West Java: A Transformation into Mega Region
NASA Astrophysics Data System (ADS)
Octifanny, Y.; Hudalah, D.
2017-07-01
In the past decade, at least three neighbouring metropolitan areas in the northwestern part of the island have been merging with each other: Jakarta Metropolitan Area (Jabodetabek), Bandung Metropolitan Area (Bandung Raya), and Cirebon Metropolitan Area (Ciayumajakuning). It is expected to be the first island-based mega-conurbation. This paper explores the potential emergence of mega region as a ground study, where mega region can be used for economic, logistic, transportation development. Authors use scoring analysis from economic and demographic indicators. The outcomes found a new and larger formation of city-region in the northern coast road networks (Pantura) - specifically western part of Java Island.
Perspectives for short timescale variability studies with Gaia
NASA Astrophysics Data System (ADS)
Roelens, M.; Eyer, L.; Mowlavi, N.; Lecoeur-Taïbi, I.; Rimoldini, L.; Blanco-Cuaresma, S.; Palaversa, L.; Süveges, M.; Charnas, J.; Wevers, T.
2017-12-01
We assess the potential of Gaia for detecting and characterizing short timescale variables, i.e. at timescale from a few seconds to a dozen hours, through extensive light-curve simulations for various short timescale variable types, including both periodic and non-periodic variability. We evidence that the variogram analysis applied to Gaia photometry should enable to detect such fast variability phenomena, down to amplitudes of a few millimagnitudes, with limited contamination from longer timescale variables or constant sources. This approach also gives valuable information on the typical timescale(s) of the considered variation, which could complement results of classical period search methods, and help prepare ground-based follow-up of the Gaia short timescale candidates.
NASA Astrophysics Data System (ADS)
Levan, P.
2010-09-01
Geosynchronous objects appear as unresolved blurs even when observed with the largest ground-based telescopes. Due to the lack of any spatial detail, two or more objects appearing at similar brightness levels within the spectral bandpass they are observed are difficult to distinguish. Observing a changing pattern of such objects from one time epoch to another showcases the deficiencies in associating individual objects before and after the configuration change. This paper explores solutions to this deficiency in the form of spectral (under small business innovative research) and phase curve analyses. The extension of the technique to phase curves proves to be a powerful new capability.
Contingent plan structures for spacecraft
NASA Technical Reports Server (NTRS)
Drummond, M.; Currie, K.; Tate, A.
1987-01-01
Most current AI planners build partially ordered plan structures which delay decisions on action ordering. Such structures cannot easily represent contingent actions. A representation which can is presented. The representation has some other useful features: it provides a good account of the causal structure of a plan, can be used to describe disjunctive actions, and it offers a planner the opportunity of even less commitment than the classical partial order on actions. The use of this representation is demonstrated in an on-board spacecraft activity sequencing problem. Contingent plan execution in a spacecraft context highlights the requirements for a fully disjunctive representation, since communication delays often prohibit extensive ground-based accounting for remotely sensed information and replanning on execution failure.
Atmospherically-driven collapse of a marine-based ice stream
NASA Astrophysics Data System (ADS)
Greenwood, S. L.; Clason, C. C.
2016-12-01
Marine-terminating glaciers and the sectors of ice sheets that are grounded below sea level are widely considered to be vulnerable to unstable retreat. The southern sector of the retreating Fennoscandian Ice Sheet comprised a large, aqueous-terminating ice sheet catchment grounded well below sea level throughout its deglaciation. However, the behaviour, timing of and controls upon ice sheet retreat through the Baltic and Bothnian basins have thus far been inferred only indirectly from peripheral, terrestrial-based geological archives. Recent acquisition of high-resolution multibeam bathymetry opens these basins up, for the first time, to direct investigation of their glacial footprint and palaeo-ice sheet behaviour. Multibeam data reveal a rich glacial landform legacy of the Bothnian Sea deglaciation. A late-stage palaeo-ice stream formed a narrow corridor of fast flow. Its pathway is overprinted by a vast field of basal crevasse squeeze ridges, while abundant traces of high subglacial meltwater volumes call for considerable input of surface meltwater to the subglacial system. We interpret a short-lived ice stream event under high extension, precipitating large-scale hydrofracture-driven collapse of the ice sheet sector under conditions of high surface melting. Experiments with a physically-based numerical flowline model indicate that the rate and pattern of Bothnian Sea ice stream retreat are most sensitive to surface mass balance change and crevasse propagation, while remarkably insensitive to submarine melting and sea level change. We interpret strongly atmospherically-driven retreat of this marine-based ice sheet sector.
Geographic Video 3d Data Model And Retrieval
NASA Astrophysics Data System (ADS)
Han, Z.; Cui, C.; Kong, Y.; Wu, H.
2014-04-01
Geographic video includes both spatial and temporal geographic features acquired through ground-based or non-ground-based cameras. With the popularity of video capture devices such as smartphones, the volume of user-generated geographic video clips has grown significantly and the trend of this growth is quickly accelerating. Such a massive and increasing volume poses a major challenge to efficient video management and query. Most of the today's video management and query techniques are based on signal level content extraction. They are not able to fully utilize the geographic information of the videos. This paper aimed to introduce a geographic video 3D data model based on spatial information. The main idea of the model is to utilize the location, trajectory and azimuth information acquired by sensors such as GPS receivers and 3D electronic compasses in conjunction with video contents. The raw spatial information is synthesized to point, line, polygon and solid according to the camcorder parameters such as focal length and angle of view. With the video segment and video frame, we defined the three categories geometry object using the geometry model of OGC Simple Features Specification for SQL. We can query video through computing the spatial relation between query objects and three categories geometry object such as VFLocation, VSTrajectory, VSFOView and VFFovCone etc. We designed the query methods using the structured query language (SQL) in detail. The experiment indicate that the model is a multiple objective, integration, loosely coupled, flexible and extensible data model for the management of geographic stereo video.
Alternative Method for the Thermospheric Atomic Oxygen Density Determination
NASA Technical Reports Server (NTRS)
Bennett, A. C.; Omidvar, K.; Atlas, Robert (Technical Monitor)
2001-01-01
Atomic oxygen density in the upper thermosphere (approximately 300 km) can be calculated using ground based incoherent scatter radar and Fabry-Perot interferometer measurements. Burnside et al. was the first to try this method, but Buonsanto et al. provided an extensive treatment of the method in 1997. This paper further examines the method using 46 nights of data collected over six years and the latest information on the oxygen collision frequency. The method is compared with the MSIS (Mass Spectrometer Incoherent Scatter)-86 atomic oxygen prediction values, which are based upon in situ rocket born and satellite measurements from the 70s to the mid-80s. In general, the method supports the MSIS-86 model, but indicates several areas of discrepancy. Furthermore, no direct correlation is found between the geomagnetic conditions and the difference between the method and MSIS-86 predictions.
Absolute stellar photometry on moderate-resolution FPA images
Stone, T.C.
2009-01-01
An extensive database of star (and Moon) images has been collected by the ground-based RObotic Lunar Observatory (ROLO) as part of the US Geological Survey program for lunar calibration. The stellar data are used to derive nightly atmospheric corrections for the observations from extinction measurements, and absolute calibration of the ROLO sensors is based on observations of Vega and published reference flux and spectrum data. The ROLO telescopes were designed for imaging the Moon at moderate resolution, thus imposing some limitations for the stellar photometry. Attaining accurate stellar photometry with the ROLO image data has required development of specialized processing techniques. A key consideration is consistency in discriminating the star core signal from the off-axis point spread function. The analysis and processing methods applied to the ROLO stellar image database are described. ?? 2009 BIPM and IOP Publishing Ltd.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Dionne, B.J.; Morris, S.C. III; Baum, J.W.
1998-01-01
The Department of Energy`s (DOE) Office of Environment, Safety, and Health (EH) sought examples of risk-based approaches to environmental restoration to include in their guidance for DOE nuclear facilities. Extensive measurements of radiological contamination in soil and ground water have been made at Brookhaven National Laboratory`s Hazardous Waste Management Facility (HWMF) as part of a Comprehensive Environmental Response, Compensation and Liability Act (CERCLA) remediation process. This provided an ideal opportunity for a case study. This report provides a risk assessment and an {open_quotes}As Low as Reasonably Achievable{close_quotes} (ALARA) analysis for use at other DOE nuclear facilities as an example ofmore » a risk-based decision technique. This document contains the Appendices for the report.« less
Overview of lunar-based astronomy
NASA Technical Reports Server (NTRS)
Smith, Harlan J.
1988-01-01
The opportunities along with the advantages and disadvantages of the Moon for astronomical observatories are carefully and methodically considered. Taking a relatively unbiased approach, it was concluded that lunar observatories will clearly be a major factor in the future of astronomy in the next century. He concludes that ground based work will continue because of its accessibility and that Earth orbital work will remain useful, primarily for convenience of access in constructing and operating very large space systems. Deep space studies will feature not only probes but extensive systems for extremely long baseline studies at wavelengths from gamma rays through visible and IR out to radio is also a conclusion drawn, along with the consideration that lunar astronomy will have found important permanent applications along lines such as are discussed at the present symposium and others quite unsuspected today.
Laczniak, R.J.; DeMeo, G.A.; Reiner, S.R.; Smith, J. LaRue; Nylund, W.E.
1999-01-01
Ash Meadows is one of the major discharge areas within the regional Death Valley ground-water flow system of southern Nevada and adjacent California. Ground water discharging at Ash Meadows is replenished from inflow derived from an extensive recharge area that includes the eastern part of the Nevada Test Site (NTS). Currently, contaminants introduced into the subsurface by past nuclear testing at NTS are the subject of study by the U.S. Department of Energy's Environmental Restoration Program. The transport of any contaminant in contact with ground water is controlled in part by the rate and direction of ground-water flow, which itself depends on the location and quantity of ground water discharging from the flow system. To best evaluate any potential risk associated with these test-generated contaminants, studies were undertaken to accurately quantify discharge from areas downgradient from the NTS. This report presents results of a study to refine the estimate of ground-water discharge at Ash Meadows. The study estimates ground-water discharge from the Ash Meadows area through a rigorous quantification of evapotranspiration (ET). To accomplish this objective, the study identifies areas of ongoing ground-water ET, delineates unique areas of ET defined on the basis of similarities in vegetation and soil-moisture conditions, and computes ET rates for each of the delineated areas. A classification technique using spectral-reflectance characteristics determined from satellite images recorded in 1992 identified seven unique units representing areas of ground-water ET. The total area classified encompasses about 10,350 acres dominated primarily by lush desert vegetation. Each unique area, referred to as an ET unit, generally consists of one or more assemblages of local phreatophytes. The ET units identified range from sparse grasslands to open water. Annual ET rates are computed by energy-budget methods from micrometeorological measurements made at 10 sites within six of the seven identified ET units. Micrometeorological data were collected for a minimum of 1 year at each site during 1994 through 1997. Evapotranspiration ranged from 0.6 foot per year in a sparse, dry saltgrass environment to 8.6 feet per year over open water. Ancillary data, including water levels, were collected during this same period to gain additional insight into the evapotranspiration process. Water levels measured in shallow wells showed annual declines of more than 10 feet and daily declines as high as 0.3 foot attributed to water losses associated with evapotranspiration. Mean annual ET from the Ash Meadows area is estimated at 21,000 acre-feet. An estimate of ground-water discharge, based on this ET estimate, is presented as a range to account for uncertainties in the contribution of local precipitation. The estimates given for mean annual ground-water discharge range from 18,000 to 21,000 acre-feet. The low estimate assumes a large contribution from local precipitation in computed ET rates; whereas, the high estimate assumes no contribution from local precipitation. The range presented is only slightly higher than previous estimates of ground-water discharge from the Ash Meadows area based primarily on springflow measurements.
Final Science Reports of the US Experiments Flown on the Russian Biosatellite Cosmos 2229
NASA Technical Reports Server (NTRS)
Connolly, James P. (Editor); Skidmore, Michael G. (Editor); Helwig, Denice A. (Editor)
1997-01-01
Cosmos 2229 was launched on December 29, 1992, containing a biological payload including two young male rhesus monkeys, insects, amphibians, and cell cultures. The biosatellite was launched from the Plesetsk Cosmodrome in Russia for a mission duration of 11.5 days. The major research objectives were: (1) Study of adaptive response mechanisms of mammals during flight; and (2) Study of physiological mechanisms underlying vestibular, motor system and brain function in primates during early and later adaptation phases. American scientists and their Russian collaborators conducted 11 experiments on this mission which included extensive preflight and postflight studies with rhesus monkeys. Biosamples and data were subsequently transferred to the United States. The U.S. responsibilities for this flight included the development of experiment protocols, the fabrication of some flight instrumentation and experiment-specific ground-based hardware, the conducting of preflight and postflight testing and the analysis of biospecimens and data for the U.S. experiments. A description of the Cosmos 2229 mission is presented in this report including preflight, on-orbit and postflight activities. The flight and ground-based bioinstrumentation which was developed by the U.S. and Russia is also described, along with the associated preflight testing ot the U.S. hardware. Final Science Reports for the experiments are also included.
Solar Spicules near and at The Limb, Observed from Hinode
NASA Technical Reports Server (NTRS)
Sterling, Alphonse C.
2009-01-01
Solar spicules appear as narrow jets emanating from the chromosphere and extending into the corona. They have been observed for over a hundred years,mainly in chromospheric spectral lines such as H-alpha. Because they are at the limit of visibility of ground-based instruments, their nature has long been a puzzle. In recent years however, vast progress has been made in understanding them both theoretically and observationally. Most recently, spicule studies have undergone revolution because of the superior resolution, time cadence, and atmosphere-free observations from the Solar Optical Telescope (SOT) instrument on the Hinode spacecraft. Here we present observations of spicules from {\\sl Hinode} SOT, and consider how the observations from Hinode compare with historical observations. We include data taken in the blue and red wings of Halpha, where the spicules have widths of a few approx.100 kms, and the longest ones reach about 10(exp 4) km in extent,similar to sizes long reported from ground-based instruments. Their dynamics are not easy to generalize, with many showing the upward movement followed by falling or fading, as traditionally reported, but with others showing more dynamic or even ejective aspects. There is a strong transverse component to their motion, as extensively reported previously from the Hinode data as evidence for Alfven waves.
NASA Astrophysics Data System (ADS)
Gabriel, Alice; Pelties, Christian
2014-05-01
In this presentation we will demonstrate the benefits of using modern numerical methods to support physic-based ground motion modeling and research. For this purpose, we utilize SeisSol an arbitrary high-order derivative Discontinuous Galerkin (ADER-DG) scheme to solve the spontaneous rupture problem with high-order accuracy in space and time using three-dimensional unstructured tetrahedral meshes. We recently verified the method in various advanced test cases of the 'SCEC/USGS Dynamic Earthquake Rupture Code Verification Exercise' benchmark suite, including branching and dipping fault systems, heterogeneous background stresses, bi-material faults and rate-and-state friction constitutive formulations. Now, we study the dynamic rupture process using 3D meshes of fault systems constructed from geological and geophysical constraints, such as high-resolution topography, 3D velocity models and fault geometries. Our starting point is a large scale earthquake dynamic rupture scenario based on the 1994 Northridge blind thrust event in Southern California. Starting from this well documented and extensively studied event, we intend to understand the ground-motion, including the relevant high frequency content, generated from complex fault systems and its variation arising from various physical constraints. For example, our results imply that the Northridge fault geometry favors a pulse-like rupture behavior.
The ESA FRM4DOAS project: Towards a quality-controlled MAXDOAS Centralized Processing System
NASA Astrophysics Data System (ADS)
Hendrick, Francois; Fayt, Caroline; Friess, Udo; Kreher, Karin; Piters, Ankie; Richter, Andreas; Wagner, Thomas; Cede, Alexander; Spinei, Elena; von Bismarck, Jonas; Fehr, Thorsten; Van Roozendael, Michel
2017-04-01
The Fiducial Reference Measurements for Ground-Based DOAS Air-Quality Observations (FRM4DOAS) is a two-year project funded by the European Space Agency (ESA). Started in July 2016, FRM4DOAS aims at further harmonizing MAXDOAS measurements and data sets, through (1) the specification of best practices for instrument operation, (2) the selection of state-of-the art retrieval algorithms, procedures, and settings, (3) the demonstration of a centralised rapid-delivery (6-24h latency) processing system for MAXDOAS instruments to be operated within the international Network for the Detection of Atmospheric Composition Change (NDACC). The project also links with the Pandonia initiative. In a first phase, the system concentrates on the development of 3 key products: NO2 vertical profiles, total O3 and tropospheric HCHO profiles, which will be retrieved at 11 MAXDOAS pilot stations. The system will also be tested and validated on data from the CINDI-2 campaign, and designed to allow further extension after commissioning. These activities will help and guarantee that homogenous, fully traceable, and quality-controlled datasets are generated from reference ground-based UV-vis instruments, which will play a crucial role in the validation of future ESA/Copernicus Sentinel satellite missions S-5P, S-4, and S-5.
Photochemistry in the Atmospheres of Denver and Mexico City
NASA Astrophysics Data System (ADS)
Cantrell, C. A.
2016-12-01
The composition of atmospheres in and downwind of urban centers has been the subject of study for decades. While early campaigns involved measurements exclusively from the ground, more recent studies have included airborne-based observations. Improved understanding has hinged critically on the development of instrumentation for better qualitifcation of pollutants, and measurement of previously unobserved species in the gas and particulate phases. Comprehensive, well-planned studies have, over time, led to more detailed understanding of chemical transformations and thus improved model representations and directions for further research. This presentation focuses on findings from two case studies of urban atmospheres, namely the MILAGRO study in the Mexico City metropolitan area and the FRAPPE study in the Denver metropolitan region. Both studies made use of extensive ground-based networks and multiple aircraft platforms. The data collected during these studies have been combined with numerical models to derive assessments of the evolution of atmospheric composition due to photochemistry, mixing, and surface processes. Here, analysis of MILAGRO data focuses on the evolution of outflow downwind of the urban region. In FRAPPE, the focus is the possible role of oil and gas exploration on urban air quality. These findings are used to assess the accuracy of current numerical models to reproduce observations, and to point toward areas possibly needing further study.
Solving the Mystery of the Short-Hard Gamma-Ray Bursts
NASA Astrophysics Data System (ADS)
Fox, Derek
2005-07-01
Eight years after the afterglow detections that revolutionized studies of the long-soft gamma-ray bursts, not even one afterglow of a short-hard GRB has been seen, and the nature of these events has become one of the most important problems in GRB research. The Swift satellite, expected to be in full operation throughout Cycle 14, will report few-arcsecond localizations for short-hard bursts in minutes, enabling prompt, deep optical afterglow searches for the first time. Discovery and observation of the first short-hard optical afterglows will answer most of the critical questions about these events: What are their distances and energies? Do they occur in distant galaxies, and if so, in which regions of those galaxies? Are they the result of collimated or quasi-spherical explosions? In combination with an extensive rapid-response ground-based campaign, we propose to make the critical high-sensitivity HST TOO observations that will allow us to answer these questions. If theorists are correct in attributing the short-hard bursts to binary neutron star coalescence events, then they will serve as signposts to the primary targeted source population for ground-based gravitational-wave detectors, and short-hard burst studies will have a vital role to play in guiding those observations.
NASA Technical Reports Server (NTRS)
Munoz, Cesar A.; Butler, Ricky (Technical Monitor)
2003-01-01
PVSio is a conservative extension to the PVS prelude library that provides basic input/output capabilities to the PVS ground evaluator. It supports rapid prototyping in PVS by enhancing the specification language with built-in constructs for string manipulation, floating point arithmetic, and input/output operations.
Federal Register 2010, 2011, 2012, 2013, 2014
2011-04-12
... polychlorinated biphenyls (PCBs) and heavy metals. An extensive history and background of the cleanup project can... that PCBs or heavy metals could stick to gear penetrating the seabed; any contaminants that come up...
COSTS TO REMEDIATE MTBE-CONTAMINATED SITES
The extensive contamination of methyl tert-butyl ether (MTBE) in ground water has introduced concerns about the increased cost of remediation of MTBE releases compared to sites with BTEX only contamination. In an attempt to evaluate these costs, cost information for 311 sites wa...
Estimation of vulnerability functions based on a global earthquake damage database
NASA Astrophysics Data System (ADS)
Spence, R. J. S.; Coburn, A. W.; Ruffle, S. J.
2009-04-01
Developing a better approach to the estimation of future earthquake losses, and in particular to the understanding of the inherent uncertainties in loss models, is vital to confidence in modelling potential losses in insurance or for mitigation. For most areas of the world there is currently insufficient knowledge of the current building stock for vulnerability estimates to be based on calculations of structural performance. In such areas, the most reliable basis for estimating vulnerability is performance of the building stock in past earthquakes, using damage databases, and comparison with consistent estimates of ground motion. This paper will present a new approach to the estimation of vulnerabilities using the recently launched Cambridge University Damage Database (CUEDD). CUEDD is based on data assembled by the Martin Centre at Cambridge University since 1980, complemented by other more-recently published and some unpublished data. The database assembles in a single, organised, expandable and web-accessible database, summary information on worldwide post-earthquake building damage surveys which have been carried out since the 1960's. Currently it contains data on the performance of more than 750,000 individual buildings, in 200 surveys following 40 separate earthquakes. The database includes building typologies, damage levels, location of each survey. It is mounted on a GIS mapping system and links to the USGS Shakemaps of each earthquake which enables the macroseismic intensity and other ground motion parameters to be defined for each survey and location. Fields of data for each building damage survey include: · Basic earthquake data and its sources · Details of the survey location and intensity and other ground motion observations or assignments at that location · Building and damage level classification, and tabulated damage survey results · Photos showing typical examples of damage. In future planned extensions of the database information on human casualties will also be assembled. The database also contains analytical tools enabling data from similar locations, building classes or ground motion levels to be assembled and thus vulnerability relationships derived for any chosen ground motion parameter, for a given class of building, and for particular countries or regions. The paper presents examples of vulnerability relationships for particular classes of buildings and regions of the world, together with the estimated uncertainty ranges. It will discuss the applicability of such vulnerability functions in earthquake loss assessment for insurance purposes or for earthquake risk mitigation.
Bozorgnia, Yousef; Abrahamson, Norman A.; Al Atik, Linda; Ancheta, Timothy D.; Atkinson, Gail M.; Baker, Jack W.; Baltay, Annemarie S.; Boore, David M.; Campbell, Kenneth W.; Chiou, Brian S.J.; Darragh, Robert B.; Day, Steve; Donahue, Jennifer; Graves, Robert W.; Gregor, Nick; Hanks, Thomas C.; Idriss, I. M.; Kamai, Ronnie; Kishida, Tadahiro; Kottke, Albert; Mahin, Stephen A.; Rezaeian, Sanaz; Rowshandel, Badie; Seyhan, Emel; Shahi, Shrey; Shantz, Tom; Silva, Walter; Spudich, Paul A.; Stewart, Jonathan P.; Watson-Lamprey, Jennie; Wooddell, Kathryn; Youngs, Robert
2014-01-01
The NGA-West2 project is a large multidisciplinary, multi-year research program on the Next Generation Attenuation (NGA) models for shallow crustal earthquakes in active tectonic regions. The research project has been coordinated by the Pacific Earthquake Engineering Research Center (PEER), with extensive technical interactions among many individuals and organizations. NGA-West2 addresses several key issues in ground-motion seismic hazard, including updating the NGA database for a magnitude range of 3.0–7.9; updating NGA ground-motion prediction equations (GMPEs) for the “average” horizontal component; scaling response spectra for damping values other than 5%; quantifying the effects of directivity and directionality for horizontal ground motion; resolving discrepancies between the NGA and the National Earthquake Hazards Reduction Program (NEHRP) site amplification factors; analysis of epistemic uncertainty for NGA GMPEs; and developing GMPEs for vertical ground motion. This paper presents an overview of the NGA-West2 research program and its subprojects.
NASA Astrophysics Data System (ADS)
Pries-Heje, Jan; Baskerville, Richard L.
This paper elaborates a design science approach for management planning anchored to the concept of a management design theory. Unlike the notions of design theories arising from information systems, management design theories can appear as a system of technological rules, much as a system of hypotheses or propositions can embody scientific theories. The paper illus trates this form of management design theories with three grounded cases. These grounded cases include a software process improvement study, a user involvement study, and an organizational change study. Collectively these studies demonstrate how design theories founded on technological rules can not only improve the design of information systems, but that these concepts have great practical value for improving the framing of strategic organi zational design decisions about such systems. Each case is either grounded in an empirical sense, that is to say, actual practice, or it is grounded to practices described extensively in the practical literature. Such design theories will help managers more easily approach complex, strategic decisions.
NASA Technical Reports Server (NTRS)
Forrest, R. B.; Eppes, T. A.; Ouellette, R. J.
1973-01-01
Studies were performed to evaluate various image positioning methods for possible use in the earth observatory satellite (EOS) program and other earth resource imaging satellite programs. The primary goal is the generation of geometrically corrected and registered images, positioned with respect to the earth's surface. The EOS sensors which were considered were the thematic mapper, the return beam vidicon camera, and the high resolution pointable imager. The image positioning methods evaluated consisted of various combinations of satellite data and ground control points. It was concluded that EOS attitude control system design must be considered as a part of the image positioning problem for EOS, along with image sensor design and ground image processing system design. Study results show that, with suitable efficiency for ground control point selection and matching activities during data processing, extensive reliance should be placed on use of ground control points for positioning the images obtained from EOS and similar programs.
Wake Vortex Transport in Proximity to the Ground
NASA Technical Reports Server (NTRS)
Hamilton, David W.; Proctor, Fred H.
2000-01-01
A sensitivity study for aircraft wake vortex transport has been conducted using a validated large eddy simulation (LES) model. The study assumes neutrally stratified and nonturbulent environments and includes the consequences of the ground. The numerical results show that the nondimensional lateral transport is primarily influenced by the magnitude of the ambient crosswind and is insensitive to aircraft type. In most of the simulations, the ground effect extends the lateral position of the downwind vortex about one initial vortex spacing (b(sub o)) in the downstream direction. Further extension by as much as one b(sub o) occurs when the downwind vortex remains 'in ground effect' (IGE) for relatively long periods of time. Results also show that a layer-averaged ambient wind velocity can be used to bound the time for lateral transport of wake vortices to insure safe operations on a parallel runway.
Orbital Express Advanced Video Guidance Sensor: Ground Testing, Flight Results and Comparisons
NASA Technical Reports Server (NTRS)
Pinson, Robin M.; Howard, Richard T.; Heaton, Andrew F.
2008-01-01
Orbital Express (OE) was a successful mission demonstrating automated rendezvous and docking. The 2007 mission consisted of two spacecraft, the Autonomous Space Transport Robotic Operations (ASTRO) and the Next Generation Serviceable Satellite (NEXTSat) that were designed to work together and test a variety of service operations in orbit. The Advanced Video Guidance Sensor, AVGS, was included as one of the primary proximity navigation sensors on board the ASTRO. The AVGS was one of four sensors that provided relative position and attitude between the two vehicles. Marshall Space Flight Center was responsible for the AVGS software and testing (especially the extensive ground testing), flight operations support, and analyzing the flight data. This paper briefly describes the historical mission, the data taken on-orbit, the ground testing that occurred, and finally comparisons between flight data and ground test data for two different flight regimes.
Adélie penguin survival: age structure, temporal variability and environmental influences.
Emmerson, Louise; Southwell, Colin
2011-12-01
The driving factors of survival, a key demographic process, have been particularly challenging to study, especially for winter migratory species such as the Adélie penguin (Pygoscelis adeliae). While winter environmental conditions clearly influence Antarctic seabird survival, it has been unclear to which environmental features they are most likely to respond. Here, we examine the influence of environmental fluctuations, broad climatic conditions and the success of the breeding season prior to winter on annual survival of an Adélie penguin population using mark-recapture models based on penguin tag and resight data over a 16-year period. This analysis required an extension to the basic Cormack-Jolly-Seber model by incorporating age structure in recapture and survival sub-models. By including model covariates, we show that survival of older penguins is primarily related to the amount and concentration of ice present in their winter foraging grounds. In contrast, fledgling and yearling survival depended on other factors in addition to the physical marine environment and outcomes of the previous breeding season, but we were unable to determine what these were. The relationship between sea-ice and survival differed with penguin age: extensive ice during the return journey to breeding colonies was detrimental to survival for the younger penguins, whereas either too little or too much ice (between 15 and 80% cover) in the winter foraging grounds was detrimental for adults. Our results demonstrate that predictions of Adélie penguin survival can be improved by taking into account penguin age, prior breeding conditions and environmental features.
Impurity Effects in Highly Frustrated Diamond-Lattice Antiferromagnets
NASA Astrophysics Data System (ADS)
Savary, Lucile
2012-02-01
We consider the effects of local impurities in highly frustrated diamond lattice antiferromagnets, which exhibit large but non-extensive ground state degeneracies. Such models are appropriate to many A-site magnetic spinels. We argue very generally that sufficiently dilute impurities induce an ordered magnetic ground state, and provide a mechanism of degeneracy breaking. The states which are selected can be determined by a ``swiss cheese model'' analysis, which we demonstrate numerically for a particular impurity model in this case. Moreover, we present criteria for estimating the stability of the resulting ordered phase to a competing frozen (spin glass) one. The results may explain the contrasting finding of frozen and ordered ground states in CoAl2O4 and MnSc2S4, respectively.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Not Available
1989-06-27
In 1981, the Koppers Coke Company Site was listed on the National Priorities List, due to extensive ground-water contamination. The 38-acre site, located in St. Paul, Minnesota, is a former coking facility that began operation in 1918. Eighteen contaminants have been identified in ground water from the surficial aquifer. Contamination has been found at a number of monitoring wells on-site and off-site, and at a residential well, a commercial well, and a cemetery well. The site is considered to be of potential public health concern because of the risk to human health caused by the possibility of exposure to hazardousmore » substances via ground water.« less
Deployment/retraction ground testing of a large flexible solar array
NASA Technical Reports Server (NTRS)
Chung, D. T.
1982-01-01
The simulated zero-gravity ground testing of the flexible fold-up solar array consisting of eighty-four full-size panels (.368 m x .4 m each) is addressed. Automatic, hands-off extension, retraction, and lockup operations are included. Three methods of ground testing were investigated: (1) vertical testing; (2) horizontal testing, using an overhead water trough to support the panels; and (3) horizontal testing, using an overhead track in conjunction with a counterweight system to support the panels. Method 3 was selected as baseline. The wing/assembly vertical support structure, the five-tier overhead track, and the mast-element support track comprise the test structure. The flexible solar array wing assembly was successfully extended and retracted numerous times under simulated zero-gravity conditions.
Hanson, R.T.; Li, Zhen; Faunt, C.C.
2004-01-01
The Santa Clara Valley is a long, narrow trough extending about 35 miles southeast from the southern end of San Francisco Bay where the regional alluvial-aquifer system has been a major source of water. Intensive agricultural and urban development throughout the 20th century and related ground-water development resulted in ground-water-level declines of more than 200 feet and land subsidence of as much as 12.7 feet between the early 1900s and the mid-1960s. Since the 1960s, Santa Clara Valley Water District has imported surface water to meet growing demands and reduce dependence on ground-water supplies. This importation of water has resulted in a sustained recovery of the ground-water flow system. To help support effective management of the ground-water resources, a regional ground-water/surface-water flow model was developed. This model simulates the flow of ground water and surface water, changes in ground-water storage, and related effects such as land subsidence. A numerical ground-water/surface-water flow model of the Santa Clara Valley subbasin of the Santa Clara Valley was developed as part of a cooperative investigation with the Santa Clara Valley Water District. The model better defines the geohydrologic framework of the regional flow system and better delineates the supply and demand components that affect the inflows to and outflows from the regional ground-water flow system. Development of the model includes revisions to the previous ground-water flow model that upgraded the temporal and spatial discretization, added source-specific inflows and outflows, simulated additional flow features such as land subsidence and multi-aquifer wellbore flow, and extended the period of simulation through September 1999. The transient-state model was calibrated to historical surface-water and ground-water data for the period 197099 and to historical subsidence for the period 198399. The regional ground-water flow system consists of multiple aquifers that are grouped into upper- and lower-aquifer systems. Ground-water inflow occurs as natural recharge in the form of streamflow infiltration and areal infiltration of precipitation along stream channels, artificial recharge from infiltration of imported water at recharge ponds and along selected stream channels, and leakage along selected transmission pipelines. Ground-water outflow occurs as evapotranspiration, stream base flow, discharge through pumpage from wells, and subsurface flow to the San Francisco Bay. The geohydrologic framework of the regional ground-water flow system was represented as six model layers. The hydraulic properties were redefined on the basis of cell-based lithologic properties that were delineated in terms of aggregate thicknesses of coarse-grained, fine-grained, and mixed textural categories. The regional aquifer systems also are dissected by several laterally extensive faults that may form at least partial barriers to the lateral flow of ground water. The spatial extent of the ground-water flow model was extended and refined to cover the entire Santa Clara Valley, including the Evergreen subregion. The temporal discretization was refined and the period of simulation was extended to 197099. The model was upgraded to MODFLOW-2000 (MF2K) and was calibrated to fit historical ground-water levels, streamflow, and land subsidence for the period 197099. The revised model slightly overestimates measured water levels with an root-mean-square error of -7.34 feet. The streamflow generally shows a good match on gaged creeks and rivers for flows greater than 1.2 cubic feet per second. The revised model also fits the measured deformation at the borehole extensometer site located near San Jose within 16 to 27 percent and the extensometer site near Sunnyvale within 3 percent of the maximum measured seasonal deformation for the deepest extensometers. The total ground-water inflow and outflow of about 225,500 acre-feet per
Fourier transform synchrotron spectroscopy of torsional and CO-stretching bands of CH 3 17 OH
NASA Astrophysics Data System (ADS)
Moruzzi, G.; Murphy, R. J.; Vos, J.; Lees, R. M.; Predoi-Cross, A.; Billinghurst, B. E.
2011-07-01
The Fourier transform spectrum of the CH 317OH isotopologue of methanol has been recorded in the 65-1200 cm -1 spectral region at a resolution of 0.00096 cm -1 using synchrotron source radiation at the Canadian Light Source. Here we present an extension to higher torsional states of our investigation of the torsion-rotation transitions within the small-amplitude vibrational ground state, now including assignments of more than 16 500 lines involving quantum numbers in the ranges v t ⩽ 3, J ⩽ 30 and | K| ⩽ 12, as well as a study of the strong CO-stretching band centered at 1020 cm -1. Energy term values have been determined for assigned ground and CO-stretching levels by use of the Ritz program, and have been fitted to series expansions in powers of J( J + 1) to determine substate origins and effective B values. Several Fermi anharmonic and Coriolis level-crossing resonances coupling the CO stretch with high torsional ground-state levels have been identified and characterized. The study is motivated by astrophysical applications, with a principal aim being the compilation of an extensive set of energy term values to permit prediction of astronomically observable sub-millimetre transitions to within an uncertainty of a few MHz.
Buried landmine detection using multivariate normal clustering
NASA Astrophysics Data System (ADS)
Duston, Brian M.
2001-10-01
A Bayesian classification algorithm is presented for discriminating buried land mines from buried and surface clutter in Ground Penetrating Radar (GPR) signals. This algorithm is based on multivariate normal (MVN) clustering, where feature vectors are used to identify populations (clusters) of mines and clutter objects. The features are extracted from two-dimensional images created from ground penetrating radar scans. MVN clustering is used to determine the number of clusters in the data and to create probability density models for target and clutter populations, producing the MVN clustering classifier (MVNCC). The Bayesian Information Criteria (BIC) is used to evaluate each model to determine the number of clusters in the data. An extension of the MVNCC allows the model to adapt to local clutter distributions by treating each of the MVN cluster components as a Poisson process and adaptively estimating the intensity parameters. The algorithm is developed using data collected by the Mine Hunter/Killer Close-In Detector (MH/K CID) at prepared mine lanes. The Mine Hunter/Killer is a prototype mine detecting and neutralizing vehicle developed for the U.S. Army to clear roads of anti-tank mines.
Checking Flight Rules with TraceContract: Application of a Scala DSL for Trace Analysis
NASA Technical Reports Server (NTRS)
Barringer, Howard; Havelund, Klaus; Morris, Robert A.
2011-01-01
Typically during the design and development of a NASA space mission, rules and constraints are identified to help reduce reasons for failure during operations. These flight rules are usually captured in a set of indexed tables, containing rule descriptions, rationales for the rules, and other information. Flight rules can be part of manual operations procedures carried out by humans. However, they can also be automated, and either implemented as on-board monitors, or as ground based monitors that are part of a ground data system. In the case of automated flight rules, one considerable expense to be addressed for any mission is the extensive process by which system engineers express flight rules in prose, software developers translate these requirements into code, and then both experts verify that the resulting application is correct. This paper explores the potential benefits of using an internal Scala DSL for general trace analysis, named TRACECONTRACT, to write executable specifications of flight rules. TRACECONTRACT can generally be applied to analysis of for example log files or for monitoring executing systems online.
Viewing ISS Data in Real Time via the Internet
NASA Technical Reports Server (NTRS)
Myers, Gerry; Chamberlain, Jim
2004-01-01
EZStream is a computer program that enables authorized users at diverse terrestrial locations to view, in real time, data generated by scientific payloads aboard the International Space Station (ISS). The only computation/communication resource needed for use of EZStream is a computer equipped with standard Web-browser software and a connection to the Internet. EZStream runs in conjunction with the TReK software, described in a prior NASA Tech Briefs article, that coordinates multiple streams of data for the ground communication system of the ISS. EZStream includes server components that interact with TReK within the ISS ground communication system and client components that reside in the users' remote computers. Once an authorized client has logged in, a server component of EZStream pulls the requested data from a TReK application-program interface and sends the data to the client. Future EZStream enhancements will include (1) extensions that enable the server to receive and process arbitrary data streams on its own and (2) a Web-based graphical-user-interface-building subprogram that enables a client who lacks programming expertise to create customized display Web pages.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Not Available
1990-09-28
The five-acre Stamina Mills site is a former textile weaving and finishing facility in North Smithfield, Providence County, Rhode Island. A portion of the site is within the 100-year floodplain and wetland area of the Branch River. The manufacturing process used cleaning solvents, acids, bases and dyes for coloring, pesticides for moth proofing, and plasticizers to coat fabrics. Mill process wastes were placed in a landfill onsite. EPA initiated three removal actions from 1984 to 1990, including an extension of the municipal water supply to residents obtaining water from the affected aquifer; and treatment of two underground and one above-groundmore » storage tanks, followed by offsite disposal. The Record of Decision (ROD) provides a final remedy and addresses both source control and management of contaminated ground water migration at the site. The primary contaminants of concern affecting the soil, debris, sediment, and ground water are VOCs including TCE and PCE; other organics including pesticides; and metals including chromium.« less
Brainard, George C; Barger, Laura K; Soler, Robert R; Hanifin, John P
2016-11-01
The review addresses the development of a new solid-state lighting system for the International Space Station (ISS) that is intended to enhance the illumination of the working and living environment of astronauts and to improve sleep, circadian entrainment, and daytime alertness. Spaceflight missions often expose astronauts and mission support ground crews to atypical sleep-wake cycles and work schedules. A recent, extensive study describes the sleep characteristics and use of sleep-promoting pharmaceuticals in astronauts before, during, and after spaceflight. The acceptability, feasibility, and efficacy of the new ISS solid-state lighting systems are currently being tested in ground-based, analog studies. Installation of this lighting system on the ISS is scheduled to begin later this year. In-flight testing of this lighting system is planned to take place during ISS spaceflight expeditions. If the new ISS lighting system is capable of improving circadian entrainment and sleep during spaceflight, it should enhance astronaut health, performance, well-being, and safety. Such an advance would open the door to future lighting applications for humans living on Earth.
HVDC Ground Electrodes - a Source of Geophysical Data
NASA Astrophysics Data System (ADS)
Freire, P. F.; Pereira, S. Y.
2015-12-01
The HVDC electrode is a component of a High Voltage Direct Current energy transmission system, and is designed to inject into the ground continuous currents up to 3500 A. The typical HVDC ground electrode is a ring of vertical conductors, 1 km wide, buried a few tens of meters.The design of a HVDC electrode is based on extensive geological, geotechnical and geophysical surveys. Geophysical data are usually electrical (VES) and electromagnetic (TEM/MT) acquisitions, for the modeling of the shallow, near-surface and deep layers of the crust. This survey aims, first, the electrode site selection, and then, at the selected site, this data is combined into a single apparent resistivity curve, which is inverted, allowing for the determination of the layered geoelectric crust model. The injection of electrical continuous current in the electrode is then simulated, with the geoelectric crust model, for the determination of the soil surface potential profile (which is usually asymmetric for different directions, due to non-1D geoelectric models).For the commissioning of a HVDC electrode, field measurements are done, such as electrode grounding resistance, soil surface potentials and metal-to-soil potentials at specific structures (buried pipelines, for instance).The geophysical data acquired during the design phase is a set of data completely independent from the electrical data acquired during the electrode commissioning phase, and both are correlated by the geoelectric model. It happens, therefore, that the geoelectric model can be calibrated based on the electrical data, with the correction of static shifts and other adjustments.This paper suggests that the commissioning of HVDC systems should be associated to a research & development program, with a university or foundation. The idea is to enjoy the opportunity of a more complete field survey, with the acquisition of a wide set of data for a better geological characterization of the area where the electrode was built.
Harden, Stephen L.; Spruill, Timothy B.
2008-01-01
An analysis of data collected at five flow-path study sites between 1997 and 2006 was performed to identify the factors needed to formulate a comprehensive program, with a focus on nitrogen, for protecting ground water and surface water in the North Carolina Coastal Plain. Water-quality protection in the Coastal Plain requires the identification of factors that affect the transport of nutrients from recharge areas to streams through the shallow ground-water system. Some basins process or retain nitrogen more readily than others, and the factors that affect nitrogen processing and retention were the focus of this investigation to improve nutrient management in Coastal Plain streams and to reduce nutrient loads to coastal waters. Nitrate reduction in ground water was observed at all five flow-path study sites in the North Carolina Coastal Plain, although the extent of reduction at each site was influenced by various environmental, hydrogeologic, and geochemical factors. Denitrification was the most common factor responsible for decreases in nitrate along the ground-water flow paths. Specific factors, some of which affect denitrification rates, that appeared to influence ground-water nitrate concentrations along the flow paths or in the streams include soil drainage, presence or absence of riparian buffers, evapotranspiration, fertilizer use, ground-water recharge rates and residence times, aquifer properties, subsurface tile drainage, sources and amounts of organic matter, and hyporheic processes. The study data indicate that the nitrate-reducing capacity of the buffer zone combined with that of the hyporheic zone can substantially lower the amount of ground-water nitrate discharged to streams in agricultural settings of the North Carolina Coastal Plain. At the watershed scale, the effects of ground-water discharge on surface-water quality appear to be greatly influenced by streamflow conditions and the presence of extensive riparian vegetation. Streamflow statistics that reflect base flow and the general hydrologic dynamics of a stream are important in understanding nutrient transport from a watershed and may be useful indicators of watersheds that are likely to have higher yields of nutrients and water. Combining streamflow statistics with information on such factors as land use, soil drainage, extent of riparian vegetation, geochemical conditions, and subsurface tile drainage in the Coastal Plain can be useful in identifying watersheds that are most likely to export excessive nitrogen due to nonpoint-source loadings and watersheds that are effective in processing nitrogen.
Qualitative Research as a Tool for Agricultural and Extension Education.
ERIC Educational Resources Information Center
Campbell, Michael; Martin, Robert
1992-01-01
Three case studies of Third World development illustrate the usefulness of qualitative research methods such as CIPP (Context, Input, Process, Product), oneshot interviews, and grounded theory. Adjusting technology to people and cultures rather than changing people to fit technology is advocated. (SK)
EFFECT OF SIMAZINE ON MALE REPRODUCTIVE DEVELOPMENT IN THE RAT
The chlorotriazine herbicides, such as atrazine, are used extensively in the United States each year. Chlorotriazine metabolites, as well as the parent compounds, have been detected in surface and ground water in areas of major usage. Previously, we found that atrazine delayed ...
NASA Astrophysics Data System (ADS)
Fankhauser, Kerstin; Guzman, Daisy R. Lucas; Oggier, Nicole; Maurer, Hansruedi; Springman, Sarah M.
2015-04-01
Various types of mass movements cause extensive natural hazards in populated mountain regions. They need to be quantified, and possibly predicted, for implementing effective mitigation and protection measures. The Meretschibach catchment in the Valais area, Switzerland, is a source region for such events. Various forms of instabilities occur on the steep slopes. They manifest themselves in form of smaller rock falls and rock slides on the open scree slopes. Moreover, large sediment volumes of channelized stream deposits can evolve into debris flows, with a substantial run-out along the Meretschibach. Geophysical methods, such as electrical resistivity tomography (ERT) and ground-penetrating-radar (GPR) have been proven to be powerful tools for characterizing mass movements and slope instabilities. They complement other remote sensing techniques and in-situ geotechnical experiments. Ground-based and helicopter-borne GPR measurements were carried out at the Meretschibach test site, to determine the depth to the bedrock. The results indicate that the bedrock is generally shallow, ranging from a few centimetres to about 5 metres vertically below the surface. A particularly interesting aspect of the GPR investigations was the observation that bedrock depth could be resolved by both, ground-based and helicopter-borne GPR data. Ground-based GPR surveying proved to be extremely challenging on the steep slopes, and some areas were even inaccessible due to safety concerns. It is therefore encouraging for future projects that helicopter-borne GPR acquisition offers a promising alternative. The spatial distribution of the soil moisture content and the temporal variations were determined with repeated ERT measurements. The resulting tomograms allowed a conductive soil layer and more resistive bedrock to be distinguished clearly. The ERT results were in good agreement with in-situ geotechnical measurements in a nearby test pit, and the depth of the soil-bedrock interface was broadly consistent with the GPR results. A comparison of tomograms obtained during the relatively dry month of June 2014, with those acquired after heavy rainfall in July 2014, showed significant changes of the shallow subsurface resistivities. These changes could be attributed in a quantitative fashion to variations of the soil water Saturation.
Analytical Model for Estimating the Zenith Angle Dependence of Terrestrial Cosmic Ray Fluxes
Sato, Tatsuhiko
2016-01-01
A new model called “PHITS-based Analytical Radiation Model in the Atmosphere (PARMA) version 4.0” was developed to facilitate instantaneous estimation of not only omnidirectional but also angular differential energy spectra of cosmic ray fluxes anywhere in Earth’s atmosphere at nearly any given time. It consists of its previous version, PARMA3.0, for calculating the omnidirectional fluxes and several mathematical functions proposed in this study for expressing their zenith-angle dependences. The numerical values of the parameters used in these functions were fitted to reproduce the results of the extensive air shower simulation performed by Particle and Heavy Ion Transport code System (PHITS). The angular distributions of ground-level muons at large zenith angles were specially determined by introducing an optional function developed on the basis of experimental data. The accuracy of PARMA4.0 was closely verified using multiple sets of experimental data obtained under various global conditions. This extension enlarges the model’s applicability to more areas of research, including design of cosmic-ray detectors, muon radiography, soil moisture monitoring, and cosmic-ray shielding calculation. PARMA4.0 is available freely and is easy to use, as implemented in the open-access EXcel-based Program for Calculating Atmospheric Cosmic-ray Spectrum (EXPACS). PMID:27490175
Analytical Model for Estimating the Zenith Angle Dependence of Terrestrial Cosmic Ray Fluxes.
Sato, Tatsuhiko
2016-01-01
A new model called "PHITS-based Analytical Radiation Model in the Atmosphere (PARMA) version 4.0" was developed to facilitate instantaneous estimation of not only omnidirectional but also angular differential energy spectra of cosmic ray fluxes anywhere in Earth's atmosphere at nearly any given time. It consists of its previous version, PARMA3.0, for calculating the omnidirectional fluxes and several mathematical functions proposed in this study for expressing their zenith-angle dependences. The numerical values of the parameters used in these functions were fitted to reproduce the results of the extensive air shower simulation performed by Particle and Heavy Ion Transport code System (PHITS). The angular distributions of ground-level muons at large zenith angles were specially determined by introducing an optional function developed on the basis of experimental data. The accuracy of PARMA4.0 was closely verified using multiple sets of experimental data obtained under various global conditions. This extension enlarges the model's applicability to more areas of research, including design of cosmic-ray detectors, muon radiography, soil moisture monitoring, and cosmic-ray shielding calculation. PARMA4.0 is available freely and is easy to use, as implemented in the open-access EXcel-based Program for Calculating Atmospheric Cosmic-ray Spectrum (EXPACS).
EARLINET: towards an advanced sustainable European aerosol lidar network
NASA Astrophysics Data System (ADS)
Pappalardo, G.; Amodeo, A.; Apituley, A.; Comeron, A.; Freudenthaler, V.; Linné, H.; Ansmann, A.; Bösenberg, J.; D'Amico, G.; Mattis, I.; Mona, L.; Wandinger, U.; Amiridis, V.; Alados-Arboledas, L.; Nicolae, D.; Wiegner, M.
2014-08-01
The European Aerosol Research Lidar Network, EARLINET, was founded in 2000 as a research project for establishing a quantitative, comprehensive, and statistically significant database for the horizontal, vertical, and temporal distribution of aerosols on a continental scale. Since then EARLINET has continued to provide the most extensive collection of ground-based data for the aerosol vertical distribution over Europe. This paper gives an overview of the network's main developments since 2000 and introduces the dedicated EARLINET special issue, which reports on the present innovative and comprehensive technical solutions and scientific results related to the use of advanced lidar remote sensing techniques for the study of aerosol properties as developed within the network in the last 13 years. Since 2000, EARLINET has developed greatly in terms of number of stations and spatial distribution: from 17 stations in 10 countries in 2000 to 27 stations in 16 countries in 2013. EARLINET has developed greatly also in terms of technological advances with the spread of advanced multiwavelength Raman lidar stations in Europe. The developments for the quality assurance strategy, the optimization of instruments and data processing, and the dissemination of data have contributed to a significant improvement of the network towards a more sustainable observing system, with an increase in the observing capability and a reduction of operational costs. Consequently, EARLINET data have already been extensively used for many climatological studies, long-range transport events, Saharan dust outbreaks, plumes from volcanic eruptions, and for model evaluation and satellite data validation and integration. Future plans are aimed at continuous measurements and near-real-time data delivery in close cooperation with other ground-based networks, such as in the ACTRIS (Aerosols, Clouds, and Trace gases Research InfraStructure Network) www.actris.net, and with the modeling and satellite community, linking the research community with the operational world, with the aim of establishing of the atmospheric part of the European component of the integrated global observing system.
Cross support overview and operations concept for future space missions
NASA Technical Reports Server (NTRS)
Stallings, William; Kaufeler, Jean-Francois
1994-01-01
Ground networks must respond to the requirements of future missions, which include smaller sizes, tighter budgets, increased numbers, and shorter development schedules. The Consultative Committee for Space Data Systems (CCSDS) is meeting these challenges by developing a general cross support concept, reference model, and service specifications for Space Link Extension services for space missions involving cross support among Space Agencies. This paper identifies and bounds the problem, describes the need to extend Space Link services, gives an overview of the operations concept, and introduces complimentary CCSDS work on standardizing Space Link Extension services.
2001-11-01
that there were· no· target misses. The Hellfire missile does not have a depleted uranium head . . -,, 2.2.2.3 Tank movement During the test, the...guide otber users through the use of this. complicated program. The_input data files for NOISEMAP consist of a root file name with several extensions...SOURCES subdirectory. This file will have the root file name followed by an accession number, then the .bps extension. The user must check the *.log
Crawley, Mark E.; Emerson, Douglas G.
1981-01-01
Lignite beds and abundant discontinuous sandstone beds of the Paleocene Sentinel Butte Member of the Fort Union Formation and sand and gravel beds in the Quarternary glaciofluvial deposits (Antelope Creek aquifer) are the most important aquifers for domestic and livestock water supplies in the West Branch Antelope Creek basin. In the Beulah-Zap lignite, ground water moves from highland area in the west toward the Antelope Creek aquifer. Water levels in the basal Sentinel Butte sandstone appear to be controlled by the level of Lake Sakakawea. In the glaciofluvial deposits of the Antelope Creek aquifer water moves from a ground-water divide northwestward to Lake Sakakawea and southeastward toward the Knife River. Large water-level declines in wells completed in the lignite and shallower aquifers could be expected with mining. The effects probably would be limited to within 1 to 2 miles of an active mine. Surface-runoff duration could be altered by increased infiltration and retention in the reclaimed are and possible temporal extension of base flow could occur. Shallow ground water beneath mine sites would be expected to increase in dissolved solids and locally to contain large sodium and sulfate concentrations. In some locations movement of poor quality water toward the Antelope Creek aquifer would be expected. (USGS)
Adams, Gregory P.; Bergman, D.L.; Pruitt, D.J.; May, J.E.; Kurklin, J.K.
1994-01-01
Ground water in the Quaternary alluvium and terrace deposits associated with the Cimarron River in northwestern Oklahoma is used extensively for irrigation, municipal, stock, and domestic supplies. The data in this report were collected as part of an investigation to provide State water managers with the quantitative knowledge necessary to manage the ground-water resource effectively. The investigation was conducted by the U.S. Geological Survey in cooperation with the Oklahoma Geological Survey. The information presented in this report include data collected in the field from 1985 through 1989, and unpublished data compiled from files of the U.S. Geological Survey and the Oklahoma Water Resources Board. Data include well and test-bole records, consisting of ground-water levels, depth of wells, principal aquifer, and primary use of water. Water levels include continuous, daily, monthly, and periodic measure- ments for selected wells. Concentrations of common chemical constituents, selected trace elements, organic analyses, and tritium analyses of water samples from wells completed in the Cimarron River alluvium and terrace deposits and Permian geologic units are reported. Winter and summer base-flow discharge measurements of the Cimarron River and its Tributaries are presented together with water-quality data from the measuring sites. Continuous water-level and precipitation-gage data are presented graphically. Locations of data- collection sites are shown on plates.
NASA Technical Reports Server (NTRS)
Bertsimas, Dimitris; Odoni, Amedeo
1997-01-01
This document presents a critical review of the principal existing optimization models that have been applied to Air Traffic Flow Management (TFM). Emphasis will be placed on two problems, the Generalized Tactical Flow Management Problem (GTFMP) and the Ground Holding Problem (GHP), as well as on some of their variations. To perform this task, we have carried out an extensive literature review that has covered more than 40 references, most of them very recent. Based on the review of this emerging field our objectives were to: (i) identify the best available models; (ii) describe typical contexts for applications of the models; (iii) provide illustrative model formulations; and (iv) identify the methodologies that can be used to solve the models. We shall begin our presentation below by providing a brief context for the models that we are reviewing. In Section 3 we shall offer a taxonomy and identify four classes of models for review. In Sections 4, 5, and 6 we shall then review, respectively, models for the Single-Airport Ground Holding Problem, the Generalized Tactical FM P and the Multi-Airport Ground Holding Problem (for the definition of these problems see Section 3 below). In each section, we identify the best available models and discuss briefly their computational performance and applications, if any, to date. Section 7 summarizes our conclusions about the state of the art.
Exploration Challenges: Transferring Ground Repair Techniques to Space Flight Application
NASA Technical Reports Server (NTRS)
McLemore, Carole A.; Kennedy, James P.; Rose, Frederick A.; Evans, Brian W.
2007-01-01
Fulfilling NASA's Vision for Space Exploration will demand an extended presence in space at distances from our home planet that exceed our current experience in space logistics and maintenance. The ability to perform repairs in lieu of the customary Orbital Replacement Unit (ORU) process where a faulty part is replaced will be elevated from contingency to routine to sustain operations. The use and cost effectiveness of field repairs for ground based operations in industry and the military have advanced with the development of technology in new materials, new repair techniques and new equipment. The unique environments, accessibility constraints and Extra Vehicular Activity (EVA) issues of space operations will require extensive assessment and evolution of these technologies to provide an equivalent and expected level of assurance to mission success. Challenges include the necessity of changes in design philosophy and policy, extremes in thermal cycling, disruptive forces (such as static charge and wind entrainment) on developed methods for control of materials, dramatically increased volatility of chemicals for cleaning and other compounds due to extremely low pressures, the limits imposed on dexterity and maneuverability by current EVA equipment and practices, and the necessity of unique verification methodology. This paper describes these challenges in and discusses the effects on the established ground techniques for repair. The paper also describes the leading repair methodology candidates and their beneficial attributes for resolving these issues with the evolution of technology.
Near Real-Time Earthquake Exposure and Damage Assessment: An Example from Turkey
NASA Astrophysics Data System (ADS)
Kamer, Yavor; Çomoǧlu, Mustafa; Erdik, Mustafa
2014-05-01
Confined by infamous strike-slip North Anatolian Fault from the north and by the Hellenic subduction trench from the south Turkey is one of the most seismically active countries in Europe. Due this increased exposure and the fragility of the building stock Turkey is among the top countries exposed to earthquake hazard in terms of mortality and economic losses. In this study we focus recent and ongoing efforts to mitigate the earthquake risk in near real-time. We present actual results of recent earthquakes, such as the M6 event off-shore Antalya which occurred on 28 December 2013. Starting at the moment of detection, we obtain a preliminary ground motion intensity distribution based on epicenter and magnitude. Our real-time application is further enhanced by the integration of the SeisComp3 ground motion parameter estimation tool with the Earthquake Loss Estimation Routine (ELER). SeisComp3 provides the online station parameters which are then automatically incorporated into the ShakeMaps produced by ELER. The resulting ground motion distributions are used together with the building inventory to calculate expected number of buildings in various damage states. All these analysis are conducted in an automated fashion and are communicated within a few minutes of a triggering event. In our efforts to disseminate earthquake information to the general public we make extensive use of social networks such as Tweeter and collaborate with mobile phone operators.
Investigation of feet functions of large ruminants with a decoupled model of equivalent mechanism
Zhang, Qun; Ding, Xilun
2017-01-01
ABSTRACT Cloven hooves of ruminants adapt to diverse terrain, provide propulsive force and support the whole body during movement in natural environments. To reveal how the feet ensure terrain adaptability by choosing the proper configurations and terrain conditions, we model the feet of ruminants as an equivalent mechanism with flexion-extension and lateral movement decoupled. The upper part of the equivalent mechanism can flex and extend, while the lower part performs the lateral movement. Combination of the two parts can adapt to longitudinal slope (anterior-posterior) and transverse slope (medial-lateral), respectively. When one of two digits closes laterally, the workspace of the other decreases. The distal interdigital ligament between two digits limits their motion by elastic force and stores energy during movement. Differences in elastic energy variation of the ligament on different transverse slopes are characterized based on the configurations of two digits and the elastic energy between them. If the upper one of two symmetric digits is fixed, the foot landing on the grade surface (2°) shows greater capacity for absorbing energy; otherwise, level ground is the best choice for ruminants. As for the asymmetric digits, longer lateral digits enhance the optimal adaptive lateral angle. The asymmetry predisposes the feet to damage on the hard ground, which indicates soft ground is more suitable. PMID:28412713
Understanding Particulate Matter Dynamics in the San Joaquin Valley during DISCOVER-AQ, 2013
NASA Astrophysics Data System (ADS)
Prabhakar, G.; Zhang, X.; Kim, H.; Parworth, C.; Pusede, S. E.; Wooldridge, P. J.; Cohen, R. C.; Zhang, Q.; Cappa, C. D.
2015-12-01
Air quality in the California San Joaquin Valley (SJV) during winter continues to be the worst in the state, failing EPA's 24-hour standard for particulate matter. Despite our improved understanding of the sources of particulate matter (PM) in the valley, air-quality models are unable to predict PM concentrations accurately. We aim to characterize periods of high particulate matter concentrations in the San Joaquin Valley based on ground and airborne measurements of aerosols and gaseous pollutants, during the DISCOVER-AQ campaign, 2013. A highly instrumented aircraft flew across the SJV making three transects in a repeatable pattern, with vertical spirals over select locations. The aircraft measurements were complemented by ground measurements at these locations, with extensive chemically-speciated measurements at a ground "supersite" at Fresno. Hence, the campaign provided a comprehensive three-dimensional view of the particulate and gaseous pollutants around the valley. The vertical profiles over the different sites indicate significant variability in the concentrations and vertical distribution of PM around the valley, which are most likely driven by differences in the combined effects of emissions, chemistry and boundary layer dynamics at each site. The observations suggest that nighttime PM is dominated by surface emissions of PM from residential fuel combustion, while early morning PM is strongly influenced by mixing of low-level, above-surface, nitrate-rich layers formed from dark chemistry overnight to the surface.
NASA Astrophysics Data System (ADS)
Lv, Hongkui; He, Huihai; Sheng, Xiangdong; Liu, Jia; Chen, Songzhan; Liu, Ye; Hou, Chao; Zhao, Jing; Zhang, Zhongquan; Wu, Sha; Wang, Yaping; Lhaaso Collaboration
2018-07-01
In the Large High Altitude Air Shower Observatory (LHAASO), one square kilometer array (KM2A), with 5242 electromagnetic particle detectors (EDs) and 1171 muon detectors (MDs), is designed to study ultra-high energy gamma-ray astronomy and cosmic ray physics. The remoteness and numerous detectors extremely demand a robust and automatic calibration procedure. In this paper, a self-calibration method which relies on the measurement of charged particles within the extensive air showers is proposed. The method is fully validated by Monte Carlo simulation and successfully applied in a KM2A prototype array experiment. Experimental results show that the self-calibration method can be used to determine the detector time offset constants at the sub-nanosecond level and the number density of particles collected by each ED with an accuracy of a few percents, which are adequate to meet the physical requirements of LHAASO experiment. This software calibration also offers an ideal method to realtime monitor the detector performances for next generation ground-based EAS experiments covering an area above square kilometers scale.
Fire hazard considerations for composites in vehicle design
NASA Technical Reports Server (NTRS)
Gordon, Rex B.
1994-01-01
Military ground vehicles fires are a significant cause of system loss, equipment damage, and crew injury in both combat and non-combat situations. During combat, the ability to successfully fight an internal fire, without losing fighting and mobility capabilities, is often the key to crew survival and mission success. In addition to enemy hits in combat, vehicle fires are initiated by electrical system failures, fuel line leaks, munitions mishaps and improper personnel actions. If not controlled, such fires can spread to other areas of the vehicle, causing extensive damage and the potential for personnel injury and death. The inherent fire safety characteristics (i.e. ignitability, compartments of these vehicles play a major roll in determining rather a newly started fire becomes a fizzle or a catastrophe. This paper addresses a systems approach to assuring optimum vehicle fire safety during the design phase of complex vehicle systems utilizing extensive uses of composites, plastic and related materials. It provides practical means for defining the potential fire hazard risks during a conceptual design phase, and criteria for the selection of composite materials based on its fire safety characteristics.
NASA Technical Reports Server (NTRS)
Rahmat-Samii, Yahya
1986-01-01
Both offset and symmetric Cassegrain reflector antennas are used in satellite and ground communication systems. It is known that the subreflector diffraction can degrade the performance of these reflectors. A geometrical theory of diffraction/physical optics analysis technique is used to investigate the effects of the extended subreflector, beyond its optical rim, on the reflector efficiency and far-field patterns. Representative numerical results are shown for an offset Cassegrain reflector antenna with different feed illumination tapers and subreflector extensions. It is observed that for subreflector extensions as small as one wavelength, noticeable improvements in the overall efficiencies can be expected. Useful design data are generated for the efficiency curves and far-field patterns.
NASA Astrophysics Data System (ADS)
Podgorski, Joel E.; Green, Alan G.; Kalscheuer, Thomas; Kinzelbach, Wolfgang K. H.; Horstmeyer, Heinrich; Maurer, Hansruedi; Rabenstein, Lasse; Doetsch, Joseph; Auken, Esben; Ngwisanyi, Tiyapo; Tshoso, Gomotsang; Jaba, Bashali Charles; Ntibinyane, Onkgopotse; Laletsang, Kebabonye
2015-03-01
Integration of information from the following sources has been used to produce a much better constrained and more complete four-unit geological/hydrological model of the Okavango Delta than previously available: (i) a 3D resistivity model determined from helicopter time-domain electromagnetic (HTEM) data recorded across most of the delta, (ii) 2D models and images derived from ground-based electrical resistance tomographic, transient electromagnetic, and high resolution seismic reflection/refraction tomographic data acquired at four selected sites in western and north-central regions of the delta, and (iii) geological details extracted from boreholes in northeastern and southeastern parts of the delta. The upper heterogeneous unit is the modern delta, which comprises extensive dry and freshwater-saturated sand and lesser amounts of clay and salt. It is characterized by moderate to high electrical resistivities and very low to low P-wave velocities. Except for images of several buried abandoned river channels, it is non-reflective. The laterally extensive underlying unit of low resistivities, low P-wave velocity, and subhorizontal reflectors very likely contains saline-water-saturated sands and clays deposited in the huge Paleo Lake Makgadikgadi (PLM), which once covered a 90,000 km2 area that encompassed the delta, Lake Ngami, the Mababe Depression, and the Makgadikgadi Basin. Examples of PLM sediments are intersected in many boreholes. Low permeability clay within the PLM unit seems to be a barrier to the downward flow of the saline water. Below the PLM unit, freshwater-saturated sand of the Paleo Okavango Megafan (POM) unit is distinguished by moderate to high resistivities, low P-wave velocity, and numerous subhorizontal reflectors. The POM unit is interpreted to be the remnants of a megafan based on the arcuate nature of its front and the semi-conical shape of its upper surface in the HTEM resistivity model. Moderate to high resistivity subhorizontal layers are consistent with this interpretation. The deepest unit is the basement with very high resistivity, high P-wave velocity, and low or complex reflectivity. The interface between the POM unit and basement is a prominent seismic reflector.
Science-based health innovation in sub-Saharan Africa
2010-01-01
In recent years emerging markets such as India, China, and Brazil have developed appropriate business models and lower-cost technological innovations to address health challenges locally and internationally. But it is not well understood what capabilities African countries, with their high disease burden, have in science-based health innovation. This gap in knowledge is addressed by this series in BMC International Health and Human Rights. The series presents the results of extensive on-the-ground research in the form of four country case studies of health and biotechnology innovation, six studies of institutions within Africa involved in health product development, and one study of health venture funds in Africa. To the best of our knowledge it is the first extensive collection of empirical work on African science-based health innovation. The four country cases are Ghana, Rwanda, Tanzania and Uganda. The six case studies of institutions are A to Z Textiles (Tanzania), Acorn Technologies (South Africa), Bioventures venture capital fund (South Africa), the Malagasy Institute of Applied Research (IMRA; Madagascar), the Kenyan Medical Research Institute (KEMRI; Kenya), and Niprisan’s development by Nigeria’s National Institute for Pharmaceutical Research and Development and Xechem (Nigeria). All of the examples highlight pioneering attempts to build technological capacity, create economic opportunities, and retain talent on a continent significantly affected by brain drain. They point to the practical challenges for innovators on the ground, and suggest potentially helpful policies, funding streams, and other support systems. For African nations, health innovation represents an opportunity to increase domestic capacity to solve health challenges; for international funders, it is an opportunity to move beyond foreign aid and dependency. The shared goal is creating self-sustaining innovation that has both health and development impacts. While this is a long-term strategy, this series shows the potential of African-led innovation, and indicates how it might balance realism against opportunity. There is ample scope to learn lessons more systematically from cases like those we discuss; to link entrepreneurs, scientists, funders, and policy-makers into a network to share opportunities and challenges; and ultimately to better support and stimulate African-led health innovation. PMID:21144069
Science-based health innovation in sub-Saharan Africa.
Al-Bader, Sara; Masum, Hassan; Simiyu, Ken; Daar, Abdallah S; Singer, Peter A
2010-12-13
In recent years emerging markets such as India, China, and Brazil have developed appropriate business models and lower-cost technological innovations to address health challenges locally and internationally. But it is not well understood what capabilities African countries, with their high disease burden, have in science-based health innovation.This gap in knowledge is addressed by this series in BMC International Health and Human Rights. The series presents the results of extensive on-the-ground research in the form of four country case studies of health and biotechnology innovation, six studies of institutions within Africa involved in health product development, and one study of health venture funds in Africa. To the best of our knowledge it is the first extensive collection of empirical work on African science-based health innovation.The four country cases are Ghana, Rwanda, Tanzania and Uganda. The six case studies of institutions are A to Z Textiles (Tanzania), Acorn Technologies (South Africa), Bioventures venture capital fund (South Africa), the Malagasy Institute of Applied Research (IMRA; Madagascar), the Kenyan Medical Research Institute (KEMRI; Kenya), and Niprisan's development by Nigeria's National Institute for Pharmaceutical Research and Development and Xechem (Nigeria).All of the examples highlight pioneering attempts to build technological capacity, create economic opportunities, and retain talent on a continent significantly affected by brain drain. They point to the practical challenges for innovators on the ground, and suggest potentially helpful policies, funding streams, and other support systems.For African nations, health innovation represents an opportunity to increase domestic capacity to solve health challenges; for international funders, it is an opportunity to move beyond foreign aid and dependency. The shared goal is creating self-sustaining innovation that has both health and development impacts. While this is a long-term strategy, this series shows the potential of African-led innovation, and indicates how it might balance realism against opportunity. There is ample scope to learn lessons more systematically from cases like those we discuss; to link entrepreneurs, scientists, funders, and policy-makers into a network to share opportunities and challenges; and ultimately to better support and stimulate African-led health innovation.
Code of Federal Regulations, 2011 CFR
2011-01-01
... Certain Training and Testing Federal Special Federal Aviation Regulation No. 93 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) AIRMEN CERTIFICATION: PILOTS, FLIGHT INSTRUCTORS, AND GROUND INSTRUCTORS Pt. 61, SFAR 93 Special Federal Aviation Regulation No. 93...
Code of Federal Regulations, 2010 CFR
2010-01-01
... Certain Training and Testing Federal Special Federal Aviation Regulation No. 93 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) AIRMEN CERTIFICATION: PILOTS, FLIGHT INSTRUCTORS, AND GROUND INSTRUCTORS Pt. 61, SFAR 93 Special Federal Aviation Regulation No. 93...
Adopting Extensible Business Reporting Language (XBRL): A Grounded Theory
ERIC Educational Resources Information Center
Cruz, Marivic
2010-01-01
In 2007 and 2008, government challenges consisted of error prone, manually intensive, and inefficient environments for financial reporting. Banking regulators worldwide faced issues with respect to transparency, timeliness, quality, and managing risks associated with accounting opacity. The general problem was the existing reporting standards and…
The Principal: Leadership for the Effective and Productive School.
ERIC Educational Resources Information Center
Bookbinder, Robert M.
This book synthesizes research findings on principal effectiveness, viewing the principal as a key factor in ensuring school effectiveness and productivity. Methodology includes an extensive literature review, participation and observation grounded in theory, and pragmatic responses to conditions and issues. Chapter 1 presents an overview of…
Motivation Interventions in Education: A Meta-Analytic Review
ERIC Educational Resources Information Center
Lazowski, Rory A.; Hulleman, Chris S.
2016-01-01
This meta-analysis provides an extensive and organized summary of intervention studies in education that are grounded in motivation theory. We identified 74 published and unpublished papers that experimentally manipulated an independent variable and measured an authentic educational outcome within an ecologically valid educational context. Our…
TREATMENT OF ARSENIC AND METALS IN GROUND WATER USING A COMPOST/ZVI PRB
One of Region 4's Regional Applied Research Efforts (RARE) projects resulted in two different studies on cleaning up the Columbia Nitrogen Superfund Site located in Charleston, SC. This site is extensively contaminated with pyrite and elemental sulfur used in phosphate fertilize...
Ground and Space Radar Volume Matching and Comparison Software
NASA Technical Reports Server (NTRS)
Morris, Kenneth; Schwaller, Mathew
2010-01-01
This software enables easy comparison of ground- and space-based radar observations. The software was initially designed to compare ground radar reflectivity from operational, ground based Sand C-band meteorological radars with comparable measurements from the Tropical Rainfall Measuring Mission (TRMM) satellite s Precipitation Radar (PR) instrument. The software is also applicable to other ground-based and space-based radars. The ground and space radar volume matching and comparison software was developed in response to requirements defined by the Ground Validation System (GVS) of Goddard s Global Precipitation Mission (GPM) project. This software innovation is specifically concerned with simplifying the comparison of ground- and spacebased radar measurements for the purpose of GPM algorithm and data product validation. This software is unique in that it provides an operational environment to routinely create comparison products, and uses a direct geometric approach to derive common volumes of space- and ground-based radar data. In this approach, spatially coincident volumes are defined by the intersection of individual space-based Precipitation Radar rays with the each of the conical elevation sweeps of the ground radar. Thus, the resampled volume elements of the space and ground radar reflectivity can be directly compared to one another.
Phase diagram of quantum critical system via local convertibility of ground state
Liu, Si-Yuan; Quan, Quan; Chen, Jin-Jun; Zhang, Yu-Ran; Yang, Wen-Li; Fan, Heng
2016-01-01
We investigate the relationship between two kinds of ground-state local convertibility and quantum phase transitions in XY model. The local operations and classical communications (LOCC) convertibility is examined by the majorization relations and the entanglement-assisted local operations and classical communications (ELOCC) via Rényi entropy interception. In the phase diagram of XY model, LOCC convertibility and ELOCC convertibility of ground-states are presented and compared. It is shown that different phases in the phase diagram of XY model can have different LOCC or ELOCC convertibility, which can be used to detect the quantum phase transition. This study will enlighten extensive studies of quantum phase transitions from the perspective of local convertibility, e.g., finite-temperature phase transitions and other quantum many-body models. PMID:27381284
NASA Astrophysics Data System (ADS)
Hendry, Martin; Woan, Graham
2007-02-01
Like the surface of a busy swimming pool, spacetime is awash with waves generated by the local and distant motions of mass and, in principle, much of this activity can be reconstructed by analysing the waveforms. However, instrumentation with a reasonable chance of directly detecting these gravitational waves has only become available within the past year, with the LIGO detectors now running at design sensitivity. Here we review the burgeoning field of observational gravitational astrophysics: using gravitational wave detectors as telescopes to help answer a wide range of astrophysical questions from neutron-star physics to cosmology. The next generation of ground-based telescopes should be able to make extensive gravitational observations of some of the more energetic events in our local universe. Looking only slightly further ahead, the space-based LISA observatory will reveal the gravitational universe in phenomenal detail, supplying high-quality data on perhaps thousands of sources, and tackling some of the most fascinating questions in contemporary astronomy.
Autonomous Flight Safety System Road Test
NASA Technical Reports Server (NTRS)
Simpson, James C.; Zoemer, Roger D.; Forney, Chris S.
2005-01-01
On February 3, 2005, Kennedy Space Center (KSC) conducted the first Autonomous Flight Safety System (AFSS) test on a moving vehicle -- a van driven around the KSC industrial area. A subset of the Phase III design was used consisting of a single computer, GPS receiver, and UPS antenna. The description and results of this road test are described in this report.AFSS is a joint KSC and Wallops Flight Facility project that is in its third phase of development. AFSS is an independent subsystem intended for use with Expendable Launch Vehicles that uses tracking data from redundant onboard sensors to autonomously make flight termination decisions using software-based rules implemented on redundant flight processors. The goals of this project are to increase capabilities by allowing launches from locations that do not have or cannot afford extensive ground-based range safety assets, to decrease range costs, and to decrease reaction time for special situations.
A Ground-Based Near Infrared Camera Array System for UAV Auto-Landing in GPS-Denied Environment.
Yang, Tao; Li, Guangpo; Li, Jing; Zhang, Yanning; Zhang, Xiaoqiang; Zhang, Zhuoyue; Li, Zhi
2016-08-30
This paper proposes a novel infrared camera array guidance system with capability to track and provide real time position and speed of a fixed-wing Unmanned air vehicle (UAV) during a landing process. The system mainly include three novel parts: (1) Infrared camera array and near infrared laser lamp based cooperative long range optical imaging module; (2) Large scale outdoor camera array calibration module; and (3) Laser marker detection and 3D tracking module. Extensive automatic landing experiments with fixed-wing flight demonstrate that our infrared camera array system has the unique ability to guide the UAV landing safely and accurately in real time. Moreover, the measurement and control distance of our system is more than 1000 m. The experimental results also demonstrate that our system can be used for UAV automatic accurate landing in Global Position System (GPS)-denied environments.
Reference NO2 calibration system for ground-based intercomparisons during NASA's GTE/CITE 2 mission
NASA Technical Reports Server (NTRS)
Fried, Alan; Nunnermacker, Linda; Cadoff, Barry; Sams, Robert; Yates, Nathan
1990-01-01
An NO2 calibration system, based on a permeation device and a two-stage dynamic dilution system, was designed, constructed, and characterized at the National Bureau of Standards. In this system, calibrant flow entering the second stage was controlled without contacting a metal flow controller, and permeation oven temperature and flow were continuously maintained, even during transport. The system performance and the permeation emission rate were characterized by extensive laboratory tests. This system was capable of accurately delivering known NO2 concentrations in the ppbv and sub-ppbv concentration range with a total uncertainty of approximately 10 percent. The calibration system was placed on board NASA research aircraft at both the Wallops Island and Ames research facilities. There it was employed as the reference standard in NASA's Global Tropospheric Experiment/Chemical Instrumental Test and Evaluation 2 mission in August 1986.
Numerical Simulation of the RTA Combustion Rig
NASA Technical Reports Server (NTRS)
Davoudzadeh, Farhad; Buehrle, Robert; Liu, Nan-Suey; Winslow, Ralph
2005-01-01
The Revolutionary Turbine Accelerator (RTA)/Turbine Based Combined Cycle (TBCC) project is investigating turbine-based propulsion systems for access to space. NASA Glenn Research Center and GE Aircraft Engines (GEAE) planned to develop a ground demonstrator engine for validation testing. The demonstrator (RTA-1) is a variable cycle, turbofan ramjet designed to transition from an augmented turbofan to a ramjet that produces the thrust required to accelerate the vehicle from Sea Level Static (SLS) to Mach 4. The RTA-1 is designed to accommodate a large variation in bypass ratios from sea level static to Mach 4 conditions. Key components of this engine are new, such as a nickel alloy fan, advanced trapped vortex combustor, a Variable Area Bypass Injector (VABI), radial flameholders, and multiple fueling zones. A means to mitigate risks to the RTA development program was the use of extensive component rig tests and computational fluid dynamics (CFD) analysis.
NASA Technical Reports Server (NTRS)
1981-01-01
The primary change in crew capsule definition is a smaller MOTV crew capsule, switching from a 3-man capsule to a 2-man capsule. A second change permitted crew accommodations for sleeping and privacy to be combined with the flight station. The current baseline DRM, ER1, requires 2 men for 3 to 4 days to repair a multi-disciplined GOE Platform and a modest amount of mission dedicated hardware. A 2-man MOTV crew capsule to be used as a design reference point for the OTV, and its interfaces between the STS and other associated equipment or facilities are described in detail. The functional capabilities of the 2-man capsule, as well as its application to a wide range of generic missions, is also presented. The MOTV turnaround is addressed and significant requirements for both space based and ground based scenarios are summarized.
Precision Cosmology: The First Half Million Years
NASA Astrophysics Data System (ADS)
Jones, Bernard J. T.
2017-06-01
Cosmology seeks to characterise our Universe in terms of models based on well-understood and tested physics. Today we know our Universe with a precision that once would have been unthinkable. This book develops the entire mathematical, physical and statistical framework within which this has been achieved. It tells the story of how we arrive at our profound conclusions, starting from the early twentieth century and following developments up to the latest data analysis of big astronomical datasets. It provides an enlightening description of the mathematical, physical and statistical basis for understanding and interpreting the results of key space- and ground-based data. Subjects covered include general relativity, cosmological models, the inhomogeneous Universe, physics of the cosmic background radiation, and methods and results of data analysis. Extensive online supplementary notes, exercises, teaching materials, and exercises in Python make this the perfect companion for researchers, teachers and students in physics, mathematics, and astrophysics.
NASA Technical Reports Server (NTRS)
Sorensen, J. A.; Goka, T.
1982-01-01
In connection with the necessity to provide greater terminal area capacity, attention is given to approaches in which the required increase in capacity will be obtained by making use of more automation and by involving the pilot to a larger degree in the air traffic control (ATC) process. It was recommended that NASA should make extensive use of its research aircraft and cockpit simulators to assist the FAA in examining the capabilities and limitations of cockpit displays of traffic information (CDTI). A program was organized which utilizes FAA ATC (ground-based) simulators and NASA aircraft and associated cockpit simulators in a research project which explores applications of the CDTI system. The present investigation is concerned with several questions related to the CDTI-based terminal area traffic tactical control concepts. Attention is given to longitudinal separation criteria, a longitudinal following model, longitudinal capture, combined longitudinal/vertical control, and lateral control.