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Sample records for radioactivity intercomparison exercise

  1. Environmental radioactive intercomparison program and radioactive standards program

    SciTech Connect

    Dilbeck, G.

    1993-12-31

    The Environmental Radioactivity Intercomparison Program described herein provides quality assurance support for laboratories involved in analyzing public drinking water under the Safe Drinking Water Act (SDWA) Regulations, and to the environmental radiation monitoring activities of various agencies. More than 300 federal and state nuclear facilities and private laboratories participate in some phase of the program. This presentation describes the Intercomparison Program studies and matrices involved, summarizes the precision and accuracy requirements of various radioactive analytes, and describes the traceability determinations involved with radioactive calibration standards distributed to the participants. A summary of program participants, sample and report distributions, and additional responsibilities of this program are discussed.

  2. International NMR-based Environmental Metabolomics Intercomparison Exercise

    EPA Science Inventory

    Several fundamental requirements must be met so that NMR-based metabolomics and the related technique of metabonomics can be formally adopted into environmental monitoring and chemical risk assessment. Here we report an intercomparison exercise which has evaluated the effectivene...

  3. PNNL Results from 2009 Silene Criticality Accident Dosimeter Intercomparison Exercise

    SciTech Connect

    Hill, Robin L.; Conrady, Matthew M.

    2010-06-30

    This document reports the results of testing of the Hanford Personnel Nuclear Accident Dosimeter (PNAD) during a criticality accident dosimeter intercomparison exercise at the CEA Valduc Center on October 13, 14, and 15, 2009.

  4. PNNL Results from 2010 CALIBAN Criticality Accident Dosimeter Intercomparison Exercise

    SciTech Connect

    Hill, Robin L.; Conrady, Matthew M.

    2011-10-28

    This document reports the results of the Hanford personnel nuclear accident dosimeter (PNAD) and fixed nuclear accident dosimeter (FNAD) during a criticality accident dosimeter intercomparison exercise at the CEA Valduc Center on September 20-23, 2010. Pacific Northwest National Laboratory (PNNL) participated in a criticality accident dosimeter intercomparison exercise at the Commissariat a Energie Atomique (CEA) Valduc Center near Dijon, France on September 20-23, 2010. The intercomparison exercise was funded by the U.S. Department of Energy, Nuclear Criticality Safety Program, with Lawrence Livermore National Laboratory as the lead Laboratory. PNNL was one of six invited DOE Laboratory participants. The other participating Laboratories were: Lawrence Livermore National Laboratory (LLNL), Los Alamos National Laboratory (LANL), Savannah River Site (SRS), the Y-12 National Security Complex at Oak Ridge, and Sandia National Laboratory (SNL). The goals of PNNL's participation in the intercomparison exercise were to test and validate the procedures and algorithm currently used for the Hanford personnel nuclear accident dosimeters (PNADs) on the metallic reactor, CALIBAN, to test exposures to PNADs from the side and from behind a phantom, and to test PNADs that were taken from a historical batch of Hanford PNADs that had varying degrees of degradation of the bare indium foil. Similar testing of the PNADs was done on the Valduc SILENE test reactor in 2009 (Hill and Conrady, 2010). The CALIBAN results are reported here.

  5. An intercomparison exercise on technetium-99 in seaweed

    SciTech Connect

    Bates, T.H. )

    1988-01-01

    This paper reports the results of an intercomparison exercise carried out on the determination of {sup 99}Tc in Fucus vesiculosus taken from the coastline adjacent to Sellafield. This species of seaweed has a very high affinity for the radionuclide (e.g., two orders of magnitude higher than has the edible prophyra species); it presents, therefore, a potential source for a biological reference material with the highest possible specific activity. Details of the preparation and homogeneity testing before distribution of samples for analysis are described and summaries of analytical procedures used by each participant are provided. The exercise was arranged by the UK Analysts' Informal Working Group and participants comprised laboratories considered to be expert in the analysis and others who were using the opportunity to demonstrate their capability to perform this type of determination. 17 refs., 4 tabs.

  6. In situ gamma-spectrometry intercomparison exercise in Salzburg, Austria

    NASA Astrophysics Data System (ADS)

    Lettner, H.; Andrasi, A.; Hubmer, A. K.; Lovranich, E.; Steger, F.; Zombori, P.

    1996-02-01

    In situ gamma-spectrometry has become a useful method of assessing the nuclide concentrations of man-made and natural gamma-emitters in the soil. For the quality assurance of the measurements, periodically conducted intercomparison exercises are essential. Therefore exercises were organized in different European countries since 1990, the last one was conducted in Salzburg, Austria in September 1994. The participation of 27 measurement teams from all over Europe emphasizes the importance of the intercomparison. Salzburg was selected because the Province of Salzburg, Austria was among the most heavily contaminated regions outside the former USSR by the Chernobyl fallout. Two different typical sites were selected for the measurements: Site 1 was inside the urban area of Salzburg on intensively used grassland which had not been tilled since the deposition of the fallout. This site is representative for intensively used agricultural regions in the Province of Salzburg. Site 2 was in the mountainous regions of the Hohe Tauern at an elevated altitude of 1600 m, representing the agricultural soil- and contamination conditions of the Alpine regions in the Tauern. The two sites differ significantly in terms of soil characteristics, a crucial parameter for the evaluation of in situ gamma-spectra. The participants used different approaches for the evaluation of the gamma-spectra in terms of considering the depth distribution. In the paper the results from the 24 European teams are presented.

  7. Intercomparison exercise within a distributed-dosimetry network.

    PubMed

    Romanyukha, A; Voss, S P; Benevides, L A

    2011-03-01

    The results of an intercomparison exercise within the US Navy dosimetric network (USN-DN) are presented and discussed. The USN-DN uses a commercially available LiF:Mg,Cu,P thermoluminescent dosemeter (TLD) model Harshaw 8840/8841 and TLD reader model Harshaw 8800 manufactured by Thermo Fisher Scientific. The USN-DN consists of a single calibration facility and 16 satellite dosimetry reading facilities throughout the world with ∼ 40 model 8800 TLD readers and in excess of 350 000 TLD cards in circulation. The Naval Dosimetry Center (NDC) is the primary calibration site responsible for the distribution and calibration of all TLD cards and their associated holders. In turn, each satellite facility is assigned a subpopulation of cards, which are utilised for servicing their local customers. Consistency of the NDC calibration of 150 dosemeters (calibrated at NDC) and 27 locally calibrated remote readers was evaluated in the framework of this intercomparison. Accuracy of TLDs' calibration, performed at the NDC, was found to be <3 % throughout the entire network. Accuracy of the readers' calibration, performed with the NDC issued calibration dosemeters at remote sites, was found to be better than 4 % for most readers. The worst performance was found for reader Channel 3, which is calibrated using the thinnest chip of the Harshaw 8840/8841 dosemeter. The loss of sensitivity of this chip may be caused by time-temperature profile that has been designed for all four chips without consideration of chip thickness. PMID:21088021

  8. An overview of results obtained in intercomparison exercises for determination of actinides.

    PubMed

    Benedik, L

    2013-11-01

    In recent years the Jožef Stefan Institute participated in numerous intercomparison exercises for determination of natural and man-made radionuclides. The reported values were mostly in good agreement with the resulting reference values. This paper describes an analysis of the measurement results obtained in intercomparison exercises for determination of actinides in the period from 2009 to 2011, organised by the National Physical Laboratory and the Bundesamt für Strahlenschutz. The review covers neptunium, plutonium and americium radioisotopes over this period. PMID:23566808

  9. The Ice Sheet Mass Balance Inter-comparison Exercise

    NASA Astrophysics Data System (ADS)

    Shepherd, A.; Ivins, E. R.

    2015-12-01

    Fluctuations in the mass of ice stored in Antarctica and Greenland are of considerable societal importance. The Ice Sheet Mass Balance Inter-Comparison Exercise (IMBIE) is a joint-initiative of ESA and NASA aimed at producing a single estimate of the global sea level contribution to polar ice sheet losses. Within IMBIE, estimates of ice sheet mass balance are developed from a variety of satellite geodetic techniques using a common spatial and temporal reference frame and a common appreciation of the contributions due to external signals. The project brings together the laboratories and space agencies that have been instrumental in developing independent estimates of ice sheet mass balance to date. In its first phase, IMBIE involved 27 science teams, and delivered a first community assessment of ice sheet mass imbalance to replace 40 individual estimates. The project established that (i) there is good agreement between the three main satellite-based techniques for estimating ice sheet mass balance, (ii) combining satellite data sets leads to significant improvement in certainty, (iii) the polar ice sheets contributed 11 ± 4 mm to global sea levels between 1992 and 2012, and (iv) that combined ice losses from Antarctica and Greenland have increased over time, rising from 10% of the global trend in the early 1990's to 30% in the late 2000's. Demand for an updated assessment has grown, and there are now new satellite missions, new geophysical corrections, new techniques, and new teams producing data. The period of overlap between independent satellite techniques has increased from 5 to 12 years, and the full period of satellite data over which an assessment can be performed has increased from 19 to 40 years. It is also clear that multiple satellite techniques are required to confidently separate mass changes associated with snowfall and ice dynamical imbalance - information that is of critical importance for climate modelling. This presentation outlines the approach

  10. Experience from Intercomparison Exercises of Radon Gas Detectors in the Years 1996-2006

    NASA Astrophysics Data System (ADS)

    Butterweck, Gernot; Schuler, Christoph

    2008-08-01

    Radon gas measuring services in Switzerland must be approved by the Federal Office for Public Health (FOPH). The maintenance of approval includes the obligation to participate in annual intercomparison exercises performed at the radon gas reference laboratory of the Paul Scherrer Institut (PSI). In eleven intercomparison exercises since 1996 a total of 1,515 radon gas detectors was subjected to radon gas exposures between 300 kBq h m-3 and 2100 kBq h m-3. Preparation and read-out of electret detectors is performed by the measuring services. About one percent of these detectors were observed with false positive results. The quality of results of etched-track detectors is determined by the quality assurance system and calibration of the supplier. In one case, a measuring service lost approval due to quality problems of the detector manufacturer. Double blind tests yielded less good results compared to the detectors of the same measuring service participating officially.

  11. Peroxy radical partitioning during the AMMA radical intercomparison exercise

    NASA Astrophysics Data System (ADS)

    Andrés-Hernández, M. D.; Stone, D.; Brookes, D. M.; Commane, R.; Reeves, C. E.; Huntrieser, H.; Heard, D. E.; Monks, P. S.; Burrows, J. P.; Schlager, H.; Kartal, D.; Evans, M. J.; Floquet, C. F. A.; Ingham, T.; Methven, J.; Parker, A. E.

    2010-11-01

    Peroxy radicals were measured onboard two scientific aircrafts during the AMMA (African Monsoon Multidisciplinary Analysis) campaign in summer 2006. This paper reports results from the flight on 16 August 2006 during which measurements of HO2 by laser induced fluorescence spectroscopy at low pressure (LIF-FAGE) and total peroxy radicals (RO2* = HO2+ΣRO2, R = organic chain) by two similar instruments based on the peroxy radical chemical amplification (PeRCA) technique were subject of a blind intercomparison. The German DLR-Falcon and the British FAAM-BAe-146 flew wing tip to wing tip for about 30 min making concurrent measurements on 2 horizontal level runs at 697 and 485 hPa over the same geographical area in Burkina Faso. A full set of supporting measurements comprising photolysis frequencies, and relevant trace gases like CO, NO, NO2, NOy, O3 and a wider range of VOCs were collected simultaneously. Results are discussed on the basis of the characteristics and limitations of the different instruments used. Generally, no data bias are identified and the RO2* data available agree quite reasonably within the instrumental errors. The [RO2*]/[HO2] ratios, which vary between 1:1 and 3:1, as well as the peroxy radical variability, concur with variations in photolysis rates and in other potential radical precursors. Model results provide additional information about dominant radical formation and loss processes.

  12. Peroxy radical partitioning during the AMMA radical intercomparison exercise

    NASA Astrophysics Data System (ADS)

    Andrés-Hernández, M. D.; Stone, D.; Brookes, D. M.; Commane, R.; Reeves, C. E.; Huntrieser, H.; Heard, D. E.; Monks, P. S.; Burrows, J. P.; Schlager, H.; Kartal, D.; Evans, M. J.; Floquet, C. F. A.; Ingham, T.; Methven, J.; Parker, A. E.

    2010-04-01

    Peroxy radicals were measured onboard two scientific aircrafts during the AMMA (African Monsoon Multidisciplinary Analysis) campaign in summer 2006. This paper reports results from the flight on 16 August 2006 during which measurements of HO2 by laser induced fluorescence spectroscopy at low pressure (LIF-FAGE) and total peroxy radicals (RO2*=HO2+ΣRO2, R= organic chain) by two similar instruments based on the peroxy radical chemical amplification (PerCA) technique were subject of a blind intercomparison. The German DLR-Falcon and the British FAAM-BAe-146 flew wing tip to wing tip for about 30 min making concurrent measurements on 2 horizontal level runs at 697 and 485 hPa over the same geographical area in Burkina Faso. A full set of supporting measurements comprising photolysis frequencies, and relevant trace gases like CO, NO, NO2, NOy, O3 and a wider range of VOCs were collected simultaneously. Results are discussed on the basis of the characteristics and limitations of the different instruments used. Generally, no data bias are identified and the RO2* data available agree quite reasonably within the instrumental errors. The [RO2*]/[HO2] ratios, which vary between 1:1 and 3:1, as well as the peroxy radical variability, concur with variations in photolysis rates and in other potential radical precursors. Model results provide additional information about dominant radical formation and loss processes.

  13. Emergency radiobioassay preparedness exercises through the NIST radiochemistry intercomparison program.

    PubMed

    Nour, Svetlana; LaRosa, Jerry; Inn, Kenneth G W

    2011-08-01

    The present challenge for the international emergency radiobioassay community is to analyze contaminated samples rapidly while maintaining high quality results. The National Institute of Standards and Technology (NIST) runs a radiobioassay measurement traceability testing program to evaluate the radioanalytical capabilities of participating laboratories. The NIST Radiochemistry Intercomparison Program (NRIP) started more than 10 years ago, and emergency performance testing was added to the program seven years ago. Radiobioassay turnaround times under the NRIP program for routine production and under emergency response scenarios are 60 d and 8 h, respectively. Because measurement accuracy and sample turnaround time are very critical in a radiological emergency, response laboratories' analytical systems are best evaluated and improved through traceable Performance Testing (PT) programs. The NRIP provides participant laboratories with metrology tools to evaluate their performance and to improve it. The program motivates the laboratories to optimize their methodologies and minimize the turnaround time of their results. Likewise, NIST has to make adjustments and periodical changes in the bioassay test samples in order to challenge the participating laboratories continually. With practice, radioanalytical measurements turnaround time can be reduced to 3-4 h. PMID:21709505

  14. IAEA INTERCOMPARISON EXERCISES OF THYROID MEASUREMENT: PERFORMANCE OF LATIN AMERICAN AND CARIBBEAN LABORATORIES.

    PubMed

    Dantas, B M; Dantas, A L A; Cruz-Suarez, R

    2016-09-01

    (131)I is widely used in Latin America and Caribbean Region in the field of nuclear medicine and has been recognised as one of the main sources of potential intake of radionuclides by the staff. The In Vivo Monitoring laboratory of the Institute for Radiation Protection and Dosimetry (IRD-CNEN-Brazil) organised three intercomparison exercises (2005, 2009 and 2013) in the scope of IAEA technical cooperation projects RLA9049 and RLA9066 aimed to disseminate and harmonise the technique for measuring (131)I in the human thyroid. The number of participants in Latin America increased from 9 to 20 institutions from 7 and 13 countries, respectively, over the last 10 y. The participants have improved significantly their ability on the in vivo measurement technique. In the 2013 round all laboratories which reported results presented performances in an acceptable range according to the ISO criteria indicating the benefit of such exercises in the region. PMID:26546253

  15. Radiation Transfer Model Intercomparison (RAMI) exercise: Results from the second phase

    NASA Astrophysics Data System (ADS)

    Pinty, B.; Widlowski, J.-L.; Taberner, M.; Gobron, N.; Verstraete, M. M.; Disney, M.; Gascon, F.; Gastellu, J.-P.; Jiang, L.; Kuusk, A.; Lewis, P.; Li, X.; Ni-Meister, W.; Nilson, T.; North, P.; Qin, W.; Su, L.; Tang, S.; Thompson, R.; Verhoef, W.; Wang, H.; Wang, J.; Yan, G.; Zang, H.

    2004-03-01

    The Radiation Transfer Model Intercomparison (RAMI) initiative is a community-driven exercise to benchmark the models of radiation transfer (RT) used to represent the reflectance of terrestrial surfaces. Systematic model intercomparisons started in 1999 as a self-organized, open-access, voluntary activity of the RT modeling community. The results of the first phase were published by [2001]. The present paper describes the benchmarking protocol and the results achieved during the second phase, which took place during 2002. This second phase included two major components: The first one included a rerun of all direct-mode tests proposed during the first phase, to accommodate the evaluation of models that have been upgraded since, and the participation of new models into the entire exercise. The second component was designed to probe the performance of three-dimensional models in complex heterogeneous environments, which closely mimic the observations of actual space instruments operating at various spatial resolutions over forest canopy systems. Phases 1 and 2 of RAMI both confirm not only that a majority of the radiation transfer models participating in RAMI are in good agreement between themselves for relatively simple radiation transfer problems but also that these models exhibit significant discrepancies when considering more complex but nevertheless realistic geophysical scenarios. Specific recommendations are provided to guide the future of this benchmarking program (Phase 3 and beyond).

  16. Results of an internal dose assessment intercomparison exercise after a EURADOS/IAEA training course.

    PubMed

    Castellani, C-M; Lopez, M A; Luciani, A; Marsh, J W; Vrba, T; Cruz-Suarez, R

    2011-03-01

    A training course named 'European Radiation Dosimetry Group/International Atomic Energy Agency Advanced Training Course on Internal Dose Assessment' was held in Czech Technical University in Prague from 2 to 6 February 2009. The course, jointly organised by the two organisations, had the aim of providing guidance on the application of IDEAS guidelines and of disseminating the results of EC CONRAD Project in relation to internal dosimetry (Work Package 5). At the end of the course a dose assessment exercise was proposed to participants. Four artificial cases, named exercises left to participants, were used to check the capabilities of application of the IDEAS guidelines, gained by participants during the event. The participants had to use both hand calculations and dedicated software, in limited time (7 h). Forty per cent of participants had solved all four cases in the allotted time. The results of the dose assessment were analysed to gain experience in types of errors assessors may make during the evaluations. The result of this intercomparison exercise was promising: half of the results in each case were equal to the 'reference evaluation estimate', which was obtained by applying the guidelines correctly. PMID:21051435

  17. EURADOS intercomparison exercise on MC modeling for the in-vivo monitoring of Am-241 in skull phantoms (Part I)

    NASA Astrophysics Data System (ADS)

    Vrba, Tomas; Nogueira, Pedro; Broggio, David; Caldeira, Margarida; Capello, Kevin; Fantínová, Karin; Figueira, Catarina; Hunt, John; Leone, Debora; Murugan, Manohari; Marzocchi, Olaf; Moraleda, Montse; Shutt, Arron; Suh, Soheigh; Takahashi, Masa; Tymińska, Katarzyna; Antonia Lopez, Maria; Tanner, Rick

    2014-11-01

    An intercomparison on in-vivo monitoring for determination of 241Am in three skull phantoms was launched by EURADOS in 2011. The project focused on the measurement and estimation of 241Am activity in the human skull. Three human skull phantoms of different complexity were used. A Monte Carlo (MC) exercise with the voxel representations of the real phantoms was also launched in September 2012. The main goals of the project were to investigate the use of MC techniques for efficiency calibrations for body monitoring systems for a special calibration exercise and compare the approaches of participating laboratories. The full MC exercise consisted of three tasks with increasing difficulty, to test the extent of the skills of each participating laboratory. The first task in this intercomparison was to simulate a specified detector and a well defined semi-skull phantom. All parameters of the simulation, including photon yield, material property and geometry were fixed. This paper provides an overview of the participants’ results and analyses of the issues presented by this first task. The majority of the responses did not need any correction and the number of incorrect results was less than in a previous exercise of a similar kind. Overall knowledge in this research area utilising MC techniques appears to have improved and the repetition of the intercomparison exercise has positively affected the skills of the participating laboratories.

  18. Proposed Design of the Third Marine Ice Sheet Model Intercomparison Exercise

    NASA Astrophysics Data System (ADS)

    Cornford, S. L.; Gudmundsson, G. H.; Pattyn, F.; Durand, G.; Martin, D. F.; Payne, A. J.

    2014-12-01

    The MISMIP and MISMIP3D marine ice sheet model intercomparison exercises have become popular benchmarks, and several modeling groups have used them to show how their models compare to both analytical results and other models. Both sets of experiments studied grounding line migration in response to changes to (in effect) properties of the grounded ice, either perturbations to the basal traction coefficient (C), or to ice softness (A). In particular, both exercises concluded that careful treatment of the grounding line was required in numerical models, either through fine resolution (typically better than 1 km), or higher order methods, or modifications to the discretization scheme. Given the success of these experiments, we propose a sequel. Like MISMIP3D, the experiments take place in a idealized, three-dimensional setting and compare full 3D (Stokes) and reduced, hydrostatic flow models. Unlike the earlier exercises, the primary focus will be the response of models to changes in ice shelf conditions, especially sub-shelf melting. The chosen configuration features an ice shelf that experiences substantial lateral shear and buttresses the upstream ice, and so is well suited to melting experiments. We also aim to design an experiment in which differences between the steady states of each model are minor compared to the response to melt-rate perturbations, a choice that reflects typical real-world applications where parameters are chosen so that the initial states of all models tend to match observations (and hence each other). We will present the MISMIP+ experiments, and show how results computed with the BISICLES ice sheet model are affected by mesh resolution, choice of flow model, and choice of melt-rate.

  19. A new methodology to assess the performance and uncertainty of source apportionment models in intercomparison exercises

    NASA Astrophysics Data System (ADS)

    Belis, C. A.; Pernigotti, D.; Karagulian, F.; Pirovano, G.; Larsen, B. R.; Gerboles, M.; Hopke, P. K.

    2015-10-01

    A new methodology to assess source apportionment model performance in intercomparison exercises, encompassing the preparation of real-world and synthetic datasets and the evaluation of the source apportionment results reported by participants, is described. The evaluation consists of three types of tests: complementary tests, preliminary tests, and performance tests. The complementary tests provide summary information about the source apportionment results as a whole. The preliminary tests check whether source/factors belong to a given source category. Three types of indicators: Pearson correlation (Pearson), standardized identity distance (SID), and weighted difference (WD) are used to test factor/source chemical profiles, while factor/source time series and contribution-to-species values are tested only using the Pearson. The performance tests, based on international standards for proficiency testing, are targeted at evaluating whether the reported biases in the quantification of the factor/source contribution estimates (SCEs) and uncertainties are consistent with previously established quality standards in a fitness-for-purpose approach. Moreover, the consistency of the SCE time series is evaluated using a variant of the RMSE normalised by the reference standard uncertainty. The described methodology facilitates a thorough evaluation of the source apportionment output. The new indicator to compare source or factor profiles presented in this study (SID) is more robust and provides additional information compared to the existing ones.

  20. FIRST EURADOS INTERCOMPARISON EXERCISE OF EYE LENS DOSEMETERS FOR MEDICAL APPLICATIONS.

    PubMed

    Clairand, I; Ginjaume, M; Vanhavere, F; Carinou, E; Daures, J; Denoziere, M; Silva, E H; Roig, M; Principi, S; Van Rycheghem, L

    2016-09-01

    In the context of the decrease in the eye lens dose limit for occupational exposure to 20 mSv per year stated by the recent revision of the European Basic Safety Standards Directive 2013/59/EURATOM, the European Radiation Dosimetry Group (EURADOS) has organised in 2014, for the first time, an intercomparison exercise for eye lens dosemeters. The main objective was to assess the capabilities of the passive eye lens dosemeters currently in use in Europe for occupational monitoring in medical fields. A total of 20 European individual monitoring services from 15 different countries have participated. The dosemeters provided by the participants were all composed of thermoluminescent detectors, of various types and designs. The irradiations were carried out with several photon fields chosen to cover the energy and angle ranges encountered in medical workplace. Participants were asked to report the doses in terms of Hp(3) using their routine protocol. The results provided by each participant were compared with the reference delivered doses. All the results were anonymously analysed. Results are globally satisfactory since, among the 20 participants, 17 were able to provide 90 % of their response in accordance with the ISO 14146 standard requirements. PMID:26163384

  1. Third Radiation Transfer Model Intercomparison (RAMI) exercise: Documenting progress in canopy reflectance models

    NASA Astrophysics Data System (ADS)

    Widlowski, J.-L.; Taberner, M.; Pinty, B.; Bruniquel-Pinel, V.; Disney, M.; Fernandes, R.; Gastellu-Etchegorry, J.-P.; Gobron, N.; Kuusk, A.; Lavergne, T.; Leblanc, S.; Lewis, P. E.; Martin, E.; Mõttus, M.; North, P. R. J.; Qin, W.; Robustelli, M.; Rochdi, N.; Ruiloba, R.; Soler, C.; Thompson, R.; Verhoef, W.; Verstraete, M. M.; Xie, D.

    2007-05-01

    The Radiation Transfer Model Intercomparison (RAMI) initiative benchmarks canopy reflectance models under well-controlled experimental conditions. Launched for the first time in 1999, this triennial community exercise encourages the systematic evaluation of canopy reflectance models on a voluntary basis. The first phase of RAMI focused on documenting the spread among radiative transfer (RT) simulations over a small set of primarily 1-D canopies. The second phase expanded the scope to include structurally complex 3-D plant architectures with and without background topography. Here sometimes significant discrepancies were noted which effectively prevented the definition of a reliable "surrogate truth," over heterogeneous vegetation canopies, against which other RT models could then be compared. The present paper documents the outcome of the third phase of RAMI, highlighting both the significant progress that has been made in terms of model agreement since RAMI-2 and the capability of/need for RT models to accurately reproduce local estimates of radiative quantities under conditions that are reminiscent of in situ measurements. Our assessment of the self-consistency and the relative and absolute performance of 3-D Monte Carlo models in RAMI-3 supports their usage in the generation of a "surrogate truth" for all RAMI test cases. This development then leads (1) to the presentation of the "RAMI Online Model Checker" (ROMC), an open-access web-based interface to evaluate RT models automatically, and (2) to a reassessment of the role, scope, and opportunities of the RAMI project in the future.

  2. The development of radioactive sample surrogates for training and exercises

    SciTech Connect

    Martha Finck; Bevin Brush; Dick Jansen; David Chamberlain; Don Dry; George Brooks; Margaret Goldberg

    2012-03-01

    The development of radioactive sample surrogates for training and exercises Source term information is required for to reconstruct a device used in a dispersed radiological dispersal device. Simulating a radioactive environment to train and exercise sampling and sample characterization methods with suitable sample materials is a continued challenge. The Idaho National Laboratory has developed and permitted a Radioactive Response Training Range (RRTR), an 800 acre test range that is approved for open air dispersal of activated KBr, for training first responders in the entry and exit from radioactively contaminated areas, and testing protocols for environmental sampling and field characterization. Members from the Department of Defense, Law Enforcement, and the Department of Energy participated in the first contamination exercise that was conducted at the RRTR in the July 2011. The range was contaminated using a short lived radioactive Br-82 isotope (activated KBr). Soil samples contaminated with KBr (dispersed as a solution) and glass particles containing activated potassium bromide that emulated dispersed radioactive materials (such as ceramic-based sealed source materials) were collected to assess environmental sampling and characterization techniques. This presentation summarizes the performance of a radioactive materials surrogate for use as a training aide for nuclear forensics.

  3. Biological dosimetry intercomparison exercise: an evaluation of triage and routine mode results by robust methods.

    PubMed

    Di Giorgio, M; Barquinero, J F; Vallerga, M B; Radl, A; Taja, M R; Seoane, A; De Luca, J; Oliveira, M Stuck; Valdivia, P; Lima, O García; Lamadrid, A; Mesa, J González; Aguilera, I Romero; Cardoso, T Mandina; Carvajal, Y C Guerrero; Maldonado, C Arceo; Espinoza, M E; Martínez-López, W; Méndez-Acuña, L; Di Tomaso, M V; Roy, L; Lindholm, C; Romm, H; Güçlü, I; Lloyd, D C

    2011-05-01

    Well-defined protocols and quality management standards are indispensable for biological dosimetry laboratories. Participation in periodic proficiency testing by interlaboratory comparisons is also required. This harmonization is essential if a cooperative network is used to respond to a mass casualty event. Here we present an international intercomparison based on dicentric chromosome analysis for dose assessment performed in the framework of the IAEA Regional Latin American RLA/9/054 Project. The exercise involved 14 laboratories, 8 from Latin America and 6 from Europe. The performance of each laboratory and the reproducibility of the exercise were evaluated using robust methods described in ISO standards. The study was based on the analysis of slides from samples irradiated with 0.75 (DI) and 2.5 Gy (DII). Laboratories were required to score the frequency of dicentrics and convert them to estimated doses, using their own dose-effect curves, after the analysis of 50 or 100 cells (triage mode) and after conventional scoring of 500 cells or 100 dicentrics. In the conntional scoring, at both doses, all reported frequencies were considered as satisfactory, and two reported doses were considered as questionable. The analysis of the data dispersion among the dicentric frequencies and among doses indicated a better reproducibility for estimated doses (15.6% for DI and 8.8% for DII) than for frequencies (24.4% for DI and 11.4% for DII), expressed by the coefficient of variation. In the two triage modes, although robust analysis classified some reported frequencies or doses as unsatisfactory or questionable, all estimated doses were in agreement with the accepted error of ±0.5 Gy. However, at the DI dose and for 50 scored cells, 5 out of the 14 reported confidence intervals that included zero dose and could be interpreted as false negatives. This improved with 100 cells, where only one confidence interval included zero dose. At the DII dose, all estimations fell within

  4. Metal measurement in aquatic environments by passive sampling methods: Lessons learning from an in situ intercomparison exercise.

    PubMed

    Dabrin, A; Ghestem, J-P; Uher, E; Gonzalez, J-L; Allan, I J; Schintu, M; Montero, N; Balaam, J; Peinerud, E; Miège, C; Coquery, M

    2016-01-01

    Passive sampling devices (PS) are widely used for pollutant monitoring in water, but estimation of measurement uncertainties by PS has seldom been undertaken. The aim of this work was to identify key parameters governing PS measurements of metals and their dispersion. We report the results of an in situ intercomparison exercise on diffusive gradient in thin films (DGT) in surface waters. Interlaboratory uncertainties of time-weighted average (TWA) concentrations were satisfactory (from 28% to 112%) given the number of participating laboratories (10) and ultra-trace metal concentrations involved. Data dispersion of TWA concentrations was mainly explained by uncertainties generated during DGT handling and analytical procedure steps. We highlight that DGT handling is critical for metals such as Cd, Cr and Zn, implying that DGT assembly/dismantling should be performed in very clean conditions. Using a unique dataset, we demonstrated that DGT markedly lowered the LOQ in comparison to spot sampling and stressed the need for accurate data calculation. PMID:26589099

  5. Results of an IAEA inter-comparison exercise to assess 137Cs and total 210Pb analytical performance in soil.

    PubMed

    Shakhashiro, A; Mabit, L

    2009-01-01

    Fallout radionuclides (FRNs) such as (210)Pb and (137)Cs have been widely used to assess soil erosion and sedimentation processes. It is of major importance to obtain accurate analytical results of FRNs by gamma analysis before any data treatment through conversion model and to allow subsequent comparison of erosion and sedimentation rates from different case studies. Therefore, IAEA organized an inter-comparison exercise to assess the validity and reliability of the analytical results of (137)Cs and total (210)Pb using gamma-spectrometry in the various laboratories participating in the IAEA Co-ordinated Research Project on "Assess the effectiveness of soil conservation measures for sustainable watershed management using fallout radionuclides". Reference materials were distributed to 14 participating laboratories and, using a rating system, their analytical results were compared to the reference values assigned. In the case of (137)Cs, the analytical results were satisfactory with 66% of the laboratories producing acceptable results. Only the sample with low (137)Cs activity (2.6+/-0.2Bqkg(-1)) gave less accurate results with more than 25% not acceptable results. The total (210)Pb analysis indicated a clear need for corrective actions in the analysis process as only 36% of the laboratories involved in the proficiency test was able to access total (210)Pb with occurrence (bias 10%). This inter-laboratory test underlines that further inter-comparison exercises should be organized by IAEA or regional laboratories to ensure the quality of the analytical data produced in Member States. As a result of the above-mentioned proficiency test, some recommendations have been provided to improve accurate gamma measurement of both (137)Cs and total (210)Pb. PMID:18760612

  6. Innovative methodology for intercomparison of radionuclide calibrators using short half-life in situ prepared radioactive sources

    SciTech Connect

    Oliveira, P. A.; Santos, J. A. M.

    2014-07-15

    Purpose: An original radionuclide calibrator method for activity determination is presented. The method could be used for intercomparison surveys for short half-life radioactive sources used in Nuclear Medicine, such as{sup 99m}Tc or most positron emission tomography radiopharmaceuticals. Methods: By evaluation of the resulting net optical density (netOD) using a standardized scanning method of irradiated Gafchromic XRQA2 film, a comparison of the netOD measurement with a previously determined calibration curve can be made and the difference between the tested radionuclide calibrator and a radionuclide calibrator used as reference device can be calculated. To estimate the total expected measurement uncertainties, a careful analysis of the methodology, for the case of{sup 99m}Tc, was performed: reproducibility determination, scanning conditions, and possible fadeout effects. Since every factor of the activity measurement procedure can influence the final result, the method also evaluates correct syringe positioning inside the radionuclide calibrator. Results: As an alternative to using a calibrated source sent to the surveyed site, which requires a relatively long half-life of the nuclide, or sending a portable calibrated radionuclide calibrator, the proposed method uses a source preparedin situ. An indirect activity determination is achieved by the irradiation of a radiochromic film using {sup 99m}Tc under strictly controlled conditions, and cumulated activity calculation from the initial activity and total irradiation time. The irradiated Gafchromic film and the irradiator, without the source, can then be sent to a National Metrology Institute for evaluation of the results. Conclusions: The methodology described in this paper showed to have a good potential for accurate (3%) radionuclide calibrators intercomparison studies for{sup 99m}Tc between Nuclear Medicine centers without source transfer and can easily be adapted to other short half-life radionuclides.

  7. The patient as a radioactive source: an intercomparison of survey meters for measurements in nuclear medicine.

    PubMed

    Uhrhan, K; Drzezga, A; Sudbrock, F

    2014-11-01

    In this work, the radiation exposure in nuclear medicine is evaluated by measuring dose rates in the proximity of patients and those in close contact to sources like capsules and syringes. A huge number of different survey meters (SMs) are offered commercially. This topic has recently gained interest since dosemeters and active personal dosemeters (APD) for the new dose quantities (ambient and directional dose equivalent) have become available. One main concern is the practical use of SMs and APD in daily clinical routines. Therefore, the radiation field of four common radiopharmaceuticals containing (18)F, (90)Y, (99m)Tc and (131)I in radioactive sources or after application to the patient was determined. Measurements were carried out with different SMs and for several distances. Dose rates decline significantly with the distance to the patient, and with some restrictions, APD can be used as SMs. PMID:25071244

  8. EURADOS intercomparison exercise on MC modelling for the in-vivo monitoring of AM-241 in skull phantoms (Part II and III).

    NASA Astrophysics Data System (ADS)

    Vrba, Tomas; Broggio, David; Caldeira, Margarida; Capello, Kevin; Fantínová, Karin; Franck, Didier; Gómez-Ros, Jose Maria; Hunt, John; Kinase, Sakae; Leone, Debora; Lombardo, Pasquale Alessandro; Manohari, Murugan; Marzocchi, Olaf; Moraleda, Montserrat; Nogueira, Pedro; Ośko, Jakub; Arron, Shutt; Suhl, Soheigh; Takahashi, Masa; Teles, Pedro; Tremblay, Marilyn; Tymińska, Katarzyna; Lopez, Maria Antonia; Tanner, Rick

    2015-08-01

    An intercomparison on in-vivo monitoring for determination of Am-241 in three skull phantoms was launched by EURADOS in 2011. The project focused on measurement and estimation of the activity of Am-241 in the human skull. Three human skull phantoms of different complexity were used. A Monte Carlo (MC) intercomparison exercise with the voxel representations of the physical phantom was launched additionally in September of 2012. The main goals of the action were (1) to investigate the different methodologies for developing MC calibrations that might arise from a complex radiological assessment and (2) to compare individual approaches of the participating laboratories in order to determine international guidance for best practice. The MC exercise consisted of three tasks with increasing difficulty, in order to test the extent of skills needed by the participating laboratory. The first task was to simulate a given detector and a well-defined semi-skull phantom. The second and third tasks presented in this paper-introduced more complex simulations with individual geometry and real detector modelling. The paper provides an overview of the participant's results, analyses of the observed issues concerning tasks two and three, and a general evaluation of the whole project.

  9. INTERCOMPARISON OF PLUTONIUM-239 MEASUREMENTS

    EPA Science Inventory

    In 1977 the U.S. Environmental Protection Agency distributed calibrated solutions of plutonium-239 to laboratories interested in participating in an intercomparison study of plutonium analysis. Participants were asked to perform a quantitative radioactivity analysis of the soluti...

  10. Dielectric measurements at 30-40 GHz and 140 GHz performed on the specimen set of the NPL intercomparison exercise

    NASA Astrophysics Data System (ADS)

    Heidinger, R.; Koeniger, F.

    1991-10-01

    Ceramic samples (BeO, Macor and quartz) and polymeric samples (Rexolite, polyethylene) are measured for a near millimeter wavelength specimen intercomparison task. The data is used to relate the results of recently established dielectric measuring facilities to results from different techniques. The Ka band (30 to 40 GHz) and D band (140 GHz) are covered by two different Fabry-Perot resonator setups. Data evaluation is discussed in detail and various correction procedures to sample thickness are tested. The results of both frequency bands coincide for most specimens. The lowest dielectric loss is found in single crystal quartz. The dielectric loss increases strongly with frequency in Rexolite only and slightly in Macor.

  11. Slovenian-Romanian bilateral intercomparison on tritium samples.

    PubMed

    Glavič-Cindro, D; Varlam, C; Faurescu, D; Vagner, I; Logar, J Kožar

    2014-05-01

    A Slovenian laboratory from the Jožef Stefan Institute (JSI) and a Romanian laboratory from the National Research and Development Institute for Cryogenics and Isotopic Technologies (ICIT) performed bilateral intercomparisons of tritium determination in environmental samples. On the basis of the results, the measurement and analysis methods were compared. Comparability and traceability were confirmed with the results from international radioactivity proficiency test exercises organized by IAEA and NPL where both laboratories participated. New knowledge gained leads to harmonized, precise and traceable results of low level tritium environmental samples measurements. PMID:24332881

  12. An inter-comparison of sediment classification methods based on multi-beam echo-sounder backscatter and sediment natural radioactivity data.

    PubMed

    Snellen, Mirjam; Eleftherakis, Dimitrios; Amiri-Simkooei, Alireza; Koomans, Ronald L; Simons, Dick G

    2013-08-01

    This contribution presents sediment classification results derived from different sources of data collected at the Dordtse Kil river, the Netherlands. The first source is a multi-beam echo-sounder (MBES). The second source is measurements taken with a gamma-ray scintillation detector, i.e., the Multi-Element Detection System for Underwater Sediment Activity (Medusa), towed over the sediments and measuring sediment natural radioactivity. Two analysis methods are employed for sediment classification based on the MBES data. The first is a Bayesian estimation method that uses the average backscatter data per beam and, therefore, is independent of the quality of the MBES calibration. The second is a model-based method that matches the measured backscatter curves to theoretical curves, predicted by a physics-based model. Medusa provides estimates for the concentrations of potassium, uranium, thorium, and cesium, known to be indicative for sediment properties, viz. mean grain size, silt content, and the presence of organic matter. In addition, a hydrophone attached to the Medusa system provides information regarding the sediment roughness. This paper presents an inter-comparison between the sediment classification results using the above-mentioned methods. It is shown that although originating from completely different sources, the MBES and Medusa provide similar information, revealing the same sediment distribution. PMID:23927095

  13. INTERLABORATORY INTERCOMPARISON OF POLONIUM-210 MEASUREMENTS

    EPA Science Inventory

    In 1975 the U.S. Environmental Protection Agency distributed calibrated solutions of polonium-210 to laboratories interested in participating in an intercomparison study of polonium-210 analysis. Participants were asked to perform a quantitative radioactivity analysis of the solu...

  14. WE-D-17A-05: Measurement of Stray Radiation Within An Active Scanning Proton Therapy Facility: EURADOS WG9 Intercomparison Exercise of Active Dosimetry Systems

    SciTech Connect

    Farah, J; Trompier, F; Stolarczyk, L; Klodowska, M; Liszka, M; Olko, P; Algranati, C; Fellin, F; Schwarz, M; Domingo, C; Romero-Exposito, M; Dufek, V; Frojdh, E; George, S; Harrison, R; Kubancak, J; Ploc, O; Knezevic, Z; Majer, M; Miljanic, S; and others

    2014-06-15

    Purpose: Intercomparison of active dosemeters in the measurement of stray radiation at the Trento active-scanning proton therapy facility. Methods: EURADOS WG9 carried out a large intercomparison exercise to test different dosemeters while measuring secondary neutrons within a 230 MeV scanned proton therapy facility. Detectors included two Bonner Sphere Spectrometers (BSS), three tissue equivalent proportional counters (TEPCHawk) and six rem-counters (Wendi II, Berthold, RadEye, a regular and an extended-range Anderson and Braun NM2B counters). Measurements of neutron ambient dose equivalents, H*(10), were done at several positions inside (8 positions) and outside (3 positions) the treatment room while irradiating a water tank phantom with a 10 × 10 × 10 cc field. Results: A generally good agreement on H*(10) values was observed for the tested detectors. At distance of 2.25 m and angles 45°, 90° and 180° with respect to the beam axis, BSS and proportional counters agreed within 30%. Higher differences (up to 60%) were observed at the closest and farthest distances, i.e. at positions where detectors sensitivity, energy, fluence and angular response are highly dependent on neutron spectra (flux and energy). The highest neutron H*(10) value, ∼60 microSv/Gy, was measured at 1.15 m along the beam axis. H*(10) decreased significantly with the distance from the isocenter dropping to 1.1 microSv/Gy at 4.25 m and 90° from beam axis, ∼2 nanoSv/Gy at the entrance of the maze, 0.2 nanoSv/Gy at the door outside the room and below detection limit in the gantry control room and at an adjacent room. These values remain considerately lower than those of passively scattered proton beams. BSS and Hawk unfolded spectra provide valuable inputs when studying the response of each detector. Conclusion: TEPCs and BSS enable accurate measurements of stray neutrons while other rem-meters also give satisfactory results but require further improvements to reduce uncertainties.

  15. Comparison exercise on activity determination of radioactive waste drums in Taiwan.

    PubMed

    Chu, Wei-Han; Yeh, Chin-Hsien; Yuan, Ming-Chen

    2016-03-01

    The National Radiation Standard Laboratory of Taiwan organized in 2014 a comparison exercise by distributing 210 L drum-typed samples to seven radioactive waste analysis laboratories in Taiwan. Four drums were filled with uniformly distributed active carbon, water, resin and concrete, respectively and five drums were filled with cracked metals and heterogeneously distributed radioactive sources. Measurement uncertainties of participants results are in the range 3–40% (k=2) and about 96% of the reported results produced En values (ISO, 1997) smaller than one for drums with activity uniformly distributed. The minimum discrepancies, expressed as Bi values (ISO, 1997), of drums with heterogeneously distributed 137Cs and 60Co were 0.34 and 0.17, respectively. PMID:27358943

  16. Inter-comparison exercises on dissolved gases for groundwater dating (GDAT 2012) : analytical uncertainties, apparent ages and other derived parameters.

    NASA Astrophysics Data System (ADS)

    Labasque, Thierry; Aquilina, Luc; Visser, Ate; Vergnaud, Virginie

    2014-05-01

    An inter-laboratory comparison exercise dedicated to environmental tracers used for groundwater dating was organized in 2012 in France. The goal was to compare sampling and analytical protocols through results obtained by the community of groundwater dating laboratories. Sampling and analytical protocols were compared through three different exercises on various supports : (1) on groundwater from a homogeneous aquifer, (2) on groundwater from a fractured heterogeneous aquifer and (3) on an air standard. The two tests allowed 31 Laboratories from 14 countries to compare their protocols for both sampling and analyses. It allows discussing the uncertainties related to sampling protocols issuing from each laboratory methods. The results show a good agreement between laboratories on the aquifers and the air standard. The dispersion of SF6 results in air standard is low (rsd 2%) compared to CFCs (rsd 3 to 7%), even if its concentration is two orders of magnitude lower. Results obtained in recent groundwater (recharge after 1980) show that the uncertainty on groundwater dating with SF6 is between 3 and 4 years. This large uncertainty is mainly due to sampling and/or analytical problems. For CFCs, uncertainties obtained over all the laboratories are less than 2 years for groundwater with recharge between 1965 and 1996. The goal of the inter-laboratory comparison exercise was also to quantify the analytical uncertainty of the 3H and noble gas measurements and to assess whether they meet the requirements for 3H/3He dating and noble gas paleotemperature reconstruction. The reproducibility of the tritium measurements was 13.5%. The reproducibility of the 3He/4He ratio and 4He, Ne, Ar, Kr and Xe concentrations was 1.4%, 1.8%, 1.5%, 2.2%, 2.9%, and 2.4%. The propagated uncertainty of the tritium and noble gas measurements meets the desired precision for typical 3H/3He dating applications. However, the measurement uncertainties for the noble gas concentrations are insufficient to

  17. EURADOS INTERCOMPARISONS IN EXTERNAL RADIATION DOSIMETRY: SIMILARITIES AND DIFFERENCES AMONG EXERCISES FOR WHOLE-BODY PHOTON, WHOLE-BODY NEUTRON, EXTREMITY, EYE-LENS AND PASSIVE AREA DOSEMETERS.

    PubMed

    Romero, Ana M; Grimbergen, Tom; McWhan, Andrew; Stadtmann, Hannes; Fantuzzi, Elena; Clairand, Isabelle; Neumaier, Stefan; Figel, Markus; Dombrowski, Harald

    2016-09-01

    The European Radiation Dosimetry Group (EURADOS) has been organising dosimetry intercomparisons for many years in response to an identified requirement from individual monitoring services (IMS) for independent performance tests for dosimetry systems. The participation in intercomparisons gives IMS the opportunity to show compliance with their own quality management system, compare results with other participants and develop plans for improving their dosimetry systems. In response to growing demand, EURADOS has increased the number of intercomparisons for external radiation dosimetry. Most of these fit into the programme of self-financing intercomparisons for dosemeters routinely used by IMS. This programme is being coordinated by EURADOS working group 2 (WG2). Up to now, this programme has included four intercomparisons for whole-body dosemeters in photon fields, one for extremity dosemeters in photon and beta fields, and one for whole-body dosemeters in neutron fields. Other EURADOS working groups have organised additional intercomparisons including events in 2014 for eye-lens dosemeters and passive area dosemeters for environmental monitoring. In this paper, the organisation and achievements of these intercomparisons are compared in detail focusing on the similarities and differences in their execution. PMID:26759475

  18. A new methodology to assess the performance and uncertainty of source apportionment models II: The results of two European intercomparison exercises

    NASA Astrophysics Data System (ADS)

    Belis, C. A.; Karagulian, F.; Amato, F.; Almeida, M.; Artaxo, P.; Beddows, D. C. S.; Bernardoni, V.; Bove, M. C.; Carbone, S.; Cesari, D.; Contini, D.; Cuccia, E.; Diapouli, E.; Eleftheriadis, K.; Favez, O.; El Haddad, I.; Harrison, R. M.; Hellebust, S.; Hovorka, J.; Jang, E.; Jorquera, H.; Kammermeier, T.; Karl, M.; Lucarelli, F.; Mooibroek, D.; Nava, S.; Nøjgaard, J. K.; Paatero, P.; Pandolfi, M.; Perrone, M. G.; Petit, J. E.; Pietrodangelo, A.; Pokorná, P.; Prati, P.; Prevot, A. S. H.; Quass, U.; Querol, X.; Saraga, D.; Sciare, J.; Sfetsos, A.; Valli, G.; Vecchi, R.; Vestenius, M.; Yubero, E.; Hopke, P. K.

    2015-12-01

    The performance and the uncertainty of receptor models (RMs) were assessed in intercomparison exercises employing real-world and synthetic input datasets. To that end, the results obtained by different practitioners using ten different RMs were compared with a reference. In order to explain the differences in the performances and uncertainties of the different approaches, the apportioned mass, the number of sources, the chemical profiles, the contribution-to-species and the time trends of the sources were all evaluated using the methodology described in Belis et al. (2015). In this study, 87% of the 344 source contribution estimates (SCEs) reported by participants in 47 different source apportionment model results met the 50% standard uncertainty quality objective established for the performance test. In addition, 68% of the SCE uncertainties reported in the results were coherent with the analytical uncertainties in the input data. The most used models, EPA-PMF v.3, PMF2 and EPA-CMB 8.2, presented quite satisfactory performances in the estimation of SCEs while unconstrained models, that do not account for the uncertainty in the input data (e.g. APCS and FA-MLRA), showed below average performance. Sources with well-defined chemical profiles and seasonal time trends, that make appreciable contributions (>10%), were those better quantified by the models while those with contributions to the PM mass close to 1% represented a challenge. The results of the assessment indicate that RMs are capable of estimating the contribution of the major pollution source categories over a given time window with a level of accuracy that is in line with the needs of air quality management.

  19. The first gamma-H2AX biodosimetry intercomparison exercise of the developing European biodosimetry network RENEB.

    PubMed

    Barnard, S; Ainsbury, E A; Al-hafidh, J; Hadjidekova, V; Hristova, R; Lindholm, C; Monteiro Gil, O; Moquet, J; Moreno, M; Rößler, U; Thierens, H; Vandevoorde, C; Vral, A; Wojewódzka, M; Rothkamm, K

    2015-04-01

    In the event of a mass casualty radiation incident, the gamma-H2AX foci assay could be a useful tool to estimate radiation doses received by individuals. The rapid processing time of blood samples of just a few hours and the potential for batch processing, enabling high throughput, make the assay ideal for early triage categorisation to separate the 'worried well' from the low and critically exposed by quantifying radiation-induced foci in peripheral blood lymphocytes. Within the RENEB framework, 8 European laboratories have taken part in the first European gamma-H2AX biodosimetry exercise, which consisted of a telescoring comparison of 200 circulated foci images taken from 8 samples, and a comparison of 10 fresh blood lymphocyte samples that were shipped overnight to participating labs 4 or 24 h post-exposure. Despite large variations between laboratories in the dose-response relationship for foci induction, the obtained results indicate that the network should be able to use the gamma-H2AX assay for rapidly identifying the most severely exposed individuals within a cohort who could then be prioritised for accurate chromosome dosimetry. PMID:25118318

  20. Exercises

    MedlinePlus

    ... Obstructive Pulmonary Disease (COPD) COPD: Lifestyle Management Exercises Exercises Make an Appointment Refer a Patient Ask a ... riding a stationary bike. Medication to Help You Exercise People with COPD often use a metered-dose ...

  1. Radioxenon standards used in laboratory inter-comparisons.

    PubMed

    Gohla, H; Auer, M; Cassette, Ph; Hague, R K; Lechermann, M; Nadalut, B

    2016-03-01

    Preparation methods for (133)Xe standards of activity concentration and the results of the 2014 (133)Xe laboratory inter-comparison exercise are described. One element of the quality assurance/quality control (QA/QC) program for laboratories of the International Monitoring System (IMS) will be regular inter-comparison exercises. However, until recently, no activity concentration standards for benchmarking were available. Therefore, two (133)Xe activity concentration reference standards were produced independently by Idaho National Laboratory and Seibersdorf Laboratories and used for the 2014 laboratory inter-comparison exercise. The preparation of a complementary (127)Xe activity concentration standard as well as a (127)Xe laboratory inter-comparison exercise suggests (127)Xe as a suitable isotope for QA/QC of remote IMS noble gas stations. PMID:26682890

  2. NOAA National Status and Trends Program Twelfth Round Intercomparison Exercise Results for Trace Metals in Marine Sediments and Biological Tissues. National Status and Trends Program for marine environmental quality: Technical memo

    SciTech Connect

    Willie, S.

    1998-11-01

    The report summarizes the results of the Twelfth Round Intercomparison for Trace Metals in Marine Sediments and Biological Tissues under the directive of the NOAA National Status and Trends Program. A total of forty-four participants were included in the exercise, including NOAA, USEPA, state, Austrailian, Canadian, Mexican and Argentinean laboratories. Two samples were sent by NRC to each participant, a marine sediment collected on the east coast of Canada and a freeze-dried mussel tissue. Laboratories were also asked to analyze two certified reference materials (CRMs) MESS-2 and CRM 2976. The elements to be determined were Al, Cr, Fe, Ni, Cu, Zn, As, Se, Ag, Cd, Sn, Hg, and Pb for both matrices, plus Be, Si, Mn, Sb, and Tl for the sediments. An accepted mean and confidence interval was calculated for each analyte in the two unknown samples, laboratory biases were identified and an overall rating of superior, good, fair or others were assigned to each laboratory.

  3. Exerciser

    NASA Technical Reports Server (NTRS)

    Lem, J. D.

    1977-01-01

    The Mark I exerciser which was added for the second and third Skylab missions, was used for a number of arm and leg exercises. This unit is a modified version of a commercial device. This is an iso-kinetic, or constant velocity, exerciser which retards the speed at which the user is allowed to move. The user applies a maximum effort and the device automatically varies the opposing resistance to maintain speed of translation at a constant preselected value.

  4. Exercise

    MedlinePlus

    ... article Exercise / physical activity with MS Judy Boone, physical therapist Lynn Williams, Dan Melfi and Dave Altman discuss ... adjusted as changes occur in MS symptoms. A physical therapist experienced with MS can be helpful in designing, ...

  5. Ozone intercomparisons from the Balloon Intercomparison Campaign

    NASA Astrophysics Data System (ADS)

    Robbins, D.; Evans, W.; Louisnard, N.; Pollitt, S.; Traub, W.; Waters, J.

    Intercomparisons of remote and in-situ techniques used to measure stratospheric ozone are made using results obtained on the Balloon Intercomparison Campaign of 1982 and 1983. Two in-situ and four remote instruments participated. These included ECC ozonesondes, a UV absorption photometer, and microwave emission, IR emission, and absorption spectrometers. Differences are generally less than 15 percent, and are within the quoted error bars. Flights which involved different sets of instruments were made on four separate days, and results are intercompared in plots of ozone density versus altitude. A careful assessment of errors was made for each instrument, and a plot of absolute errors versus altitude is given.

  6. The decommissioning of accelerators: an exercise in the recycling of radioactive material

    NASA Astrophysics Data System (ADS)

    Höfert, M.; Tuyn, J. W. N.; Forkel-Wirth, D.

    1999-06-01

    Compared with the number of nuclear power plants that will be decommissioned over the next few years accelerators are only a "small" source of radioactivity although at CERN the total amount of mostly metallic material activated in the operation of the accelerators is estimated to be of the order of 15 Mtons. Various existing approaches to classify and administer radioactive material will be presented with all of them clearly earmarked by the requirements of the nuclear cycle. There are however important differences between activation in reactors and accelerators that will be worked out. It will be shown that an attitude based on reuse or recycling of activated accelerator material should be preferred to the elimination as radioactive waste.

  7. Models and Measurements Intercomparison 2

    NASA Technical Reports Server (NTRS)

    Park, Jae H. (Editor); Ko, Malcolm K. W. (Editor); Jackman, Charles H. (Editor); Plumb, R. Alan (Editor); Kaye, Jack A. (Editor); Sage, Karen H. (Editor)

    1999-01-01

    Models and Measurement Intercomparison II (MM II) summarizes the intercomparison of results from model simulations and observations of stratospheric species. Representatives from twenty-three modeling groups using twenty-nine models participated in these MM II exercises between 1996 and 1999. Twelve of the models were two- dimensional zonal-mean models while seventeen were three-dimensional models. This was an international effort as seven were from outside the United States. Six transport experiments and five chemistry experiments were designed for various models. Models participating in the transport experiments performed simulations of chemically inert tracers providing diagnostics for transport. The chemistry experiments involved simulating the distributions of chemically active trace cases including ozone. The model run conditions for dynamics and chemistry were prescribed in order to minimize the factors that caused differences in the models. The report includes a critical review of the results by the participants and a discussion of the causes of differences between modeled and measured results as well as between results from different models, A sizable effort went into preparation of the database of the observations. This included a new climatology for ozone. The report should help in evaluating the results from various predictive models for assessing humankind perturbations of the stratosphere.

  8. Instrument intercomparisons and assessments

    NASA Astrophysics Data System (ADS)

    Albritton, D. L.; Zander, R. J.; Farmer, C. B.; Hilsenrath, E.; Mankin, W. G.; Murcray, D. G.; Pollitt, S.; Robbins, D. E.; Roscoe, H.

    Over the past few years, several field campaigns were devoted to the goal of assessing instrument reliability, as opposed to solely obtaining data to answer a geophysical question. Some examples of the formal instrument intercomparisons that have occurred in the past decade and those that are planned for the very near future are listed chronologically. Balloon-borne techniques and instruments that address the height profiles of the trace species in the lower stratosphere are emphasized. Beginning with the most extensively studied trace constituent, the approach taken and the results obtained, are described. The current status of the measurement capabilities are summarized, and the needs for future intercomparisons and assessments are listed.

  9. The April 1994 and October 1994 radon intercomparisons at EML

    SciTech Connect

    Fisenne, I.M.; George, A.C.; Perry, P.M.; Keller, H.W.

    1995-10-01

    Quality assurance/quality control (QA/QC) are the backbone of many commercial and research processes and programs. QA/QC research tests the state of a functioning system, be it the production of manufactured goods or the ability to make accurate and precise measurements. The quality of the radon measurements in the US have been tested under controlled conditions in semi-annual radon gas intercomparison exercises sponsored by the Environmental Measurements Laboratory (EML) since 1981. The two Calendar Year 1994 radon gas intercomparison exercises were conducted in the EML exposure chamber. Thirty-two groups including US Federal facilities, USDOE contractors, national and state laboratories, universities and foreign institutions participated in these exercises. The majority of the participant`s results were within {+-}10% of the EML value at radon concentrations of 570 and 945 Bq m{sup {minus}3}.

  10. Titan atmospheric models intercomparison

    NASA Astrophysics Data System (ADS)

    Pernot, P.

    2008-09-01

    Several groups over the world have developed independently models of the photochemistry of Titan. The Cassini mission reveals daily that the chemical complexity is beyond our expectations e. g. observation of heavy positive and negative ions..., and the models are updated accordingly. At this stage, there is no consensus on the various input parameters, and it becomes increasingly difficult to compare outputs form different models. An ISSI team of experts of those models will be gathered shortly to proceed to an intercomparison, i.e. to assess how the models behave, given identical sets of inputs (collectively defined). Expected discrepancies will have to be elucidated and reduced. This intercomparison will also be an occasion to estimate explicitly the importance of various physicalchemical processes on model predictions versus observations. More robust and validated models are expected from this study for the interpretation of Titanrelated data.

  11. EURADOS intercomparison on emergency radiobioassay.

    PubMed

    Li, Chunsheng; Battisti, Paolo; Berard, Philippe; Cazoulat, Alain; Cuellar, Antonio; Cruz-Suarez, Rodolfo; Dai, Xiongxin; Giardina, Isabella; Hammond, Derek; Hernandez, Carolina; Kiser, Stephen; Ko, Raymond; Kramer-Tremblay, Sheila; Lecompte, Yannick; Navarro, Eva; Navas, Cristina; Sadi, Baki; Sierra, Inmaculada; Verrezen, Freddy; Lopez, Maria A

    2015-12-01

    Nine laboratories participated in an intercomparison exercise organised by the European Radiation Dosimetry Group (EURADOS) for emergency radiobioassay involving four high-risk radionuclides ((239)Pu, (241)Am, (90)Sr and (226)Ra). Diverse methods of analysis were used by the participating laboratories for the in vitro determination of each of the four radionuclides in urine samples. Almost all the methods used are sensitive enough to meet the requirements for emergency radiobioassay derived for this project in reference to the Clinical Decision Guide introduced by the NCRP. Results from most of the methods meet the requirements of ISO 28218 on accuracy in terms of relative bias and relative precision. However, some technical gaps have been identified. For example, some laboratories do not have the ability to assay samples containing (226)Ra, and sample turnaround time would be expected to be much shorter than that reported by many laboratories, as timely results for internal contamination and early decisions on medical intervention are highly desired. Participating laboratories are expected to learn from each other on the methods used to improve the interoperability among these laboratories. PMID:25543132

  12. SECOND LATIN AMERICAN INTERCOMPARISON ON INTERNAL DOSE ASSESSMENT.

    PubMed

    Rojo, A; Puerta, N; Gossio, S; Gómez Parada, I; Cruz Suarez, R; López, E; Medina, C; Lastra Boylan, J; Pinheiro Ramos, M; Mora Ramírez, E; Alves Dos Reis, A; Yánez, H; Rubio, J; Vironneau Janicek, L; Somarriba Vanegas, F; Puerta Ortiz, J; Salas Ramírez, M; López Bejerano, G; da Silva, T; Miri Oliveira, C; Terán, M; Alfaro, M; García, T; Angeles, A; Duré Romero, E; Farias de Lima, F

    2016-09-01

    Internal dosimetry intercomparisons are essential for the verification of applied models and the consistency of results'. To that aim, the First Regional Intercomparison was organised in 2005, and that results led to the Second Regional Intercomparison Exercise in 2013, which was organised in the frame of the RLA 9/066 and coordinated by Autoridad Regulatoria Nuclear of Argentina. Four simulated cases covering intakes of (131)I, (137)Cs and Tritium were proposed. Ninteen centres from thirteen different countries participated in this exercise. This paper analyses the participants' results in this second exercise in order to test their skills and acquired knowledge, particularly in the application of the IDEAS Guidelines. It is important to highlight the increased number of countries that participated in this exercise compared with the first one and, furthermore, the improvement in the overall performance. The impact of the International Atomic Energy Agency (IAEA) Projects since 2003 has led to a significant enhancement of internal dosimetry capabilities that strengthen the radiation protection of workers. PMID:26503854

  13. Reference materials and intercomparison samples available from the Environmental Monitoring Systems Laboratory - Las Vegas

    SciTech Connect

    Kantor, E.J.; Laska, P.R.

    1985-06-01

    Reference materials and intercomparison samples may be obtained by laboratories involved in the analysis of environmental samples containing radioactivity, pesticides, toxic inorganic species, or toxic organic species. These reference materials and intercomparison samples are available from the US Environmental Protection Agency's Quality Assurance Division located at the Environmental Monitoring Systems Laboratory in Las Vegas (EMSL-LV). These materials are useful for incorporation into a laboratory's quality control program for the evaluation of the precision and accuracy of analytical work. Media used for radiation reference materials are pitchblende, Monazite ore, uranium mill tailings, Mancos shale, fly ash, and water spiked with radionuclides. Radioactivity intercomparison samples consist of water, milk, air, urine, and a simulated diet slurry spiked with radionuclides. Media available for toxic organic reference materials are sludge, shale oil, and rag oil, and for intercomparison samples are soil and water. Characterized fly ash, foundry sludge, and river sediment serve as reference materials for toxic inorganics, while spiked soil and water serve as intercomparison samples. Finally, spiked adipose tissue, blood plasma, urine, and water comprise the pesticide intercomparison samples, and, after the disclosure of the true pesticide compositions and concentrations of these samples, the laboratory can use the samples as reference materials. The reference materials are generally available continuously, but the intercomparison samples are distributed on a scheduled basis and in some cases only to certain laboratories. 9 tables.

  14. Intercomparison of personal dosimetry for service providers in Pakistan.

    PubMed

    Jabeen, Akhter; Salman, Syed Ahmad

    2009-02-01

    An intercomparison exercise for personal dosimetry service providers within Pakistan was conducted by the Health Physics Division of the Pakistan Institute of Nuclear Science and Technology. Participation in the exercise was on voluntary basis. The exercise was carried out to harmonize individual dose monitoring techniques for high energy photons in terms of a new operational quantity, namely personal dose equivalent Hp(10), for personal dosimetry in accordance with the recommendations of the International Commission on Radiation Units and Measurements. Each laboratory submitted 25 dosimeters for participation in the intercomparison exercise. Protection level Co and Cs sources were used for irradiation of dosimeters on a water phantom according to International Atomic Energy Agency protocol at the Secondary Standard Dosimetry Laboratory. Hp(10) doses for five different dose levels were measured by the participating laboratories. The ratios of measured dose/true dose (Hm/Ht) remained in the range of 0.66 to 1.11 for the Co source and 0.84 to 1.17 for the Cs source. Performance of service providers' laboratories to measure Hp(10) doses was analyzed and evaluated in terms of trumpet curves plotted for photons at a 95% confidence level. PMID:19125056

  15. Results of the EURADOS extremity dosemeter intercomparison 2009.

    PubMed

    Stadtmann, H; Grimbergen, T W M; Figel, M; Romero, A M; McWhan, A F

    2011-03-01

    This paper presents the results of an intercomparison for extremity dosemeters organised by the European radiation dosimetry group in 2009. In total, 59 systems were tested during this exercise including ring, stall and wrist dosemeters. A total of 1652 dosemeters were irradiated in the selected fields of photons and beta radiation qualities on appropriate phantoms (ISO finger and pillar phantom) in the dose quantity H(p)(0.07). All irradiations were carried out in selected accredited reference dosemetry laboratories (Seibersdorf Laboratories, Austria and IRSN, France). The results show that, especially at low-energy beta radiations ((85)Kr) and for beta irradiations with large angles of incidence (60°), many tested systems show pronounced under responses. On the other hand, for photon irradiations down to energies of 16 keV most systems showed good results. A participants meeting was held at IM2010 with discussion on both general aspects of this intercomparison and specific problems. PMID:21196458

  16. SOIL moisture data intercomparison

    NASA Astrophysics Data System (ADS)

    Kerr, Yann; Rodriguez-Frenandez, Nemesio; Al-Yaari, Amen; Parens, Marie; Molero, Beatriz; Mahmoodi, Ali; Mialon, Arnaud; Richaume, Philippe; Bindlish, Rajat; Mecklenburg, Susanne; Wigneron, Jean-Pierre

    2016-04-01

    The Soil Moisture and Ocean Salinity satellite (SMOS) was launched in November 2009 and started delivering data in January 2010. Subsequently, the satellite has been in operation for over 6 years while the retrieval algorithms from Level 1 to Level 2 underwent significant evolutions as knowledge improved. Other approaches for retrieval at Level 2 over land were also investigated while Level 3 and 4 were initiated. In this présentation these improvements are assessed by inter-comparisons of the current Level 2 (V620) against the previous version (V551) and new products either using neural networks or Level 3. In addition a global evaluation of different SMOS soil moisture (SM) products is performed comparing products with those of model simulations and other satellites (AMSR E/ AMSR2 and ASCAT). Finally, all products were evaluated against in situ measurements of soil moisture (SM). The study demonstrated that the V620 shows a significant improvement (including those at level1 improving level2)) with respect to the earlier version V551. Results also show that neural network based approaches can yield excellent results over areas where other products are poor. Finally, global comparison indicates that SMOS behaves very well when compared to other sensors/approaches and gives consistent results over all surfaces from very dry (African Sahel, Arizona), to wet (tropical rain forests). RFI (Radio Frequency Interference) is still an issue even though detection has been greatly improved while RFI sources in several areas of the world are significantly reduced. When compared to other satellite products, the analysis shows that SMOS achieves its expected goals and is globally consistent over different eco climate regions from low to high latitudes and throughout the seasons.

  17. Invited Article: Radon and thoron intercomparison experiments for integrated monitors at NIRS, Japan

    SciTech Connect

    Janik, M. Ishikawa, T.; Omori, Y.; Kavasi, N.

    2014-02-15

    Inhalation of radon ({sup 222}Rn) and its short-lived decay products and of products of the thoron ({sup 220}Rn) series accounts for more than half of the effective dose from natural radiation sources. At this time, many countries have begun large-scale radon and thoron surveys and many different measurement methods and instruments are used in these studies. Consequently, it is necessary to improve and standardize technical methods of measurements and to verify quality assurance by intercomparisons between laboratories. Four international intercomparisons for passive integrating radon and thoron monitors were conducted at the NIRS (National Institute of Radiological Sciences, Japan). Radon exercises were carried out in the 24.4 m{sup 3} inner volume walk-in radon chamber that has systems to control radon concentration, temperature, and humidity. Moreover, the NIRS thoron chamber with a 150 dm{sup 3} inner volume was utilized to provide three thoron intercomparisons. At present, the NIRS is the only laboratory world-wide that has carried out periodic thoron intercomparison of passive monitors. Fifty laboratories from 26 countries participated in the radon intercomparison, using six types of detectors (charcoal, CR-39, LR 115, polycarbonate film, electret plate, and silicon photodiode). Eighteen laboratories from 12 countries participated in the thoron intercomparisons, using two etch-track types (CR-39 and polycarbonate) detectors. The tests were made under one to three different exposures to radon and thoron. The data presented in this paper indicated that the performance quality of laboratories for radon measurement has been gradually increasing. Results of thoron exercises showed that the quality for thoron measurements still needs further development and additional studies are needed to improve its measuring methods. The present paper provides a summary of all radon and thoron international intercomparisons done at NIRS from 2007 to date and it describes the

  18. Urine Radiobioassay Intercomparison Results From The Intercomparison Studies Program At Oak Ridge National Laboratory

    SciTech Connect

    Bores, Norman; Schultz, Michael K

    2008-01-01

    The Intercomparison Studies Program (ISP) at the Oak Ridge National Laboratory (ORNL, Oak Ridge, TN USA) provides natural-matrix human urine quality-assurance/quality-control (QA/QC) samples to radiobioassay analysis laboratories. Samples are provided to these laboratories as 'single-blind' or 'double-blind' unknowns, spiked with radioactive-solution standards at 'low' levels (e.g., 0-250 mBq {center_dot} kg{sup -1} for alpha-emitters). Participants use the results as a tool for self-evaluation and a measure of performance. In this paper, sample preparation and the results of testing during the years 2000-2004 for the radionuclides natural uranium (U-nat), {sup 238}Pu, {sup 239}Pu, and {sup 241}Am are presented and discussed.

  19. Exercise: Benefits of Exercise

    MedlinePlus Videos and Cool Tools

    ... show that people with arthritis, heart disease, or diabetes benefit from regular exercise. Exercise also helps people ... or difficulty walking. To learn about exercise and diabetes, see "Exercise and Type 2 Diabetes" from Go4Life®, ...

  20. Radionuclide analyses of urine samples: results of an intercomparison

    NASA Astrophysics Data System (ADS)

    Dalheimer, A. R.; Beyer, D.; Günther, E. W.; Henrichs, K.

    1996-02-01

    The measurement of radioactivity concentrations in urine samples is an important tool for monitoring possible radionuclide intakes by occupationally exposed workers, especially for radionuclides emitting alpha or beta radiation. Quality assurance requires systematic intercomparisons involving all laboratories responsible for these measurements. Such analyses were performed by the German—Swiss Radiation Protection Association. The main purpose of these measurements was the specification of criteria for the acceptance of laboratories by radiation protection authorities. This contribution presents some measurement results of Th-nat, 90Sr, and 241Am in urine and discusses the implications for internal dosimetry.

  1. Fourth Personnel Dosimetry Intercomparison Study

    SciTech Connect

    Dickson, H.W.

    1980-02-01

    The fourth Personnel Dosimetry Intercomparison Study was held at the Oak Ridge National Laboratory's Dosimetry Applications Research Facility during March 15-23, 1978. The Health Physics Research Reactor (HPRR) used unshielded, with a 12-cm-thick Lucite shield, a 20-cm-thick concrete shield, or a 5-cm-thick steel and 15-cm-thick concrete shield, and provided four neutron and gamma-ray spectra. Then the dose was calculated based on the HPRR neutron spectra and dose conversion factors which had been determined previously for the four spectra. The results of these personnel dosimetry intercomparison studies reveal that estimates of dose equivalent vary over a wide range. The standard deviation of the mean of participants data for gamma measurements was in the range of 29 to 43%; for neutrons it was 57 to 188%. (PCS)

  2. NOAA national status and trends program eleventh round intercomparison exercise results for trace metals in marine sediments and biological tissues. National status and trends program for marine environmental quality: Technical memo

    SciTech Connect

    Willie, S.

    1997-12-01

    A total of thirty-nine participants were included in the exercise, including OAA, USEPA, state, Australian, Canadian, Mexican and Argentinean laboratories. Two samples were sent by NRC to each participant, and contaminated marine sediment from Esquimalt harbor in British Columbia and a freeze-dried oyster tissue. Laboratories were also asked to analyze two certified reference materials (CRMs) MESS-2 and CRM 2976. The elements to be determined were Al, Cr, Fe, Ni, Cu, Zn, As, Se, Ag, Cd, Sn, Hg and Pb for both matrices, plus Be, Si, Mn, Sb and Tl for the sediments. An accepted mean and confidence interval was calculated for each analyte in the two unknown samples, laboratory biases were identified and an overall rating of superior, good, fair or others were assigned to each laboratory.

  3. Intercomparison of Retrospective Radon Detectors

    SciTech Connect

    Field, R W.; Steck, D J.; Parkhurst, Maryann ); Mahaffey, Judith A. ); Alavanja, M C.

    1998-11-01

    We performed both a laboratory and field intercomparison of two novel glass-based retrospective radon detectors previously used in major radon case-control studies performed in Missouri and Iowa. The new detectors estimate retrospective residential radon exposure from the accumulation of a long-lived radon decay product, Pb-210, in glass. The detectors use track registration material in direct contact with glass surfaces to measure the alpha emission of a Pb-210 decay product, Po-210. The detector's track density generation rate (tracks cm{sup -2} hr{sup -1}) is proportional to the surface alpha activity. In the absence of other strong sources of alpha emission in the glass, the implanted surface alpha activity should be proportional to the accumulated Po-210 and hence, the cumulative radon gas exposure. The goals of the intercomparison were to: (1) perform collocated measurements using two different glass-based retrospective radon detectors in a controlled laboratory environment to compare their relative response to implanted polonium in the absence of environmental variation, (2) perform collocated measurements using two different retrospective radon progeny detectors in a variety of residential settings to compare their detection of glass implanted polonium activities, and (3) examine the correlation between track density rates and contemporary radon gas concentrations. The laboratory results suggested that the materials and methods used by the studies produced similar track densities in detectors exposed to the same implanted Po-210 activity. The field phase of the intercomparison found excellent agreement between the track density rates for the two types of retrospective detectors. The correlation between the track density rates and direct contemporary radon concentration measurements was relatively high, considering that no adjustments were performed to account for either the residential depositional environment or glass surface type.

  4. Nuclear accident dosimetry intercomparison studies.

    PubMed

    Sims, C S

    1989-09-01

    Twenty-two nuclear accident dosimetry intercomparison studies utilizing the fast-pulse Health Physics Research Reactor at the Oak Ridge National Laboratory have been conducted since 1965. These studies have provided a total of 62 different organizations a forum for discussion of criticality accident dosimetry, an opportunity to test their neutron and gamma-ray dosimetry systems under a variety of simulated criticality accident conditions, and the experience of comparing results with reference dose values as well as with the measured results obtained by others making measurements under identical conditions. Sixty-nine nuclear accidents (27 with unmoderated neutron energy spectra and 42 with eight different shielded spectra) have been simulated in the studies. Neutron doses were in the 0.2-8.5 Gy range and gamma doses in the 0.1-2.0 Gy range. A total of 2,289 dose measurements (1,311 neutron, 978 gamma) were made during the intercomparisons. The primary methods of neutron dosimetry were activation foils, thermoluminescent dosimeters, and blood sodium activation. The main methods of gamma dose measurement were thermoluminescent dosimeters, radiophotoluminescent glass, and film. About 68% of the neutron measurements met the accuracy guidelines (+/- 25%) and about 52% of the gamma measurements met the accuracy criterion (+/- 20%) for accident dosimetry. PMID:2777549

  5. Ozone Differential Absorption Lidar Algorithm Intercomparison

    NASA Astrophysics Data System (ADS)

    Godin, Sophie; Carswell, Allen I.; Donovan, David P.; Claude, Hans; Steinbrecht, Wolfgang; McDermid, I. Stuart; McGee, Thomas J.; Gross, Michael R.; Nakane, Hideaki; Swart, Daan P. J.; Bergwerff, Hans B.; Uchino, Osamu; von der Gathen, Peter; Neuber, Roland

    1999-10-01

    An intercomparison of ozone differential absorption lidar algorithms was performed in 1996 within the framework of the Network for the Detection of Stratospheric Changes (NDSC) lidar working group. The objective of this research was mainly to test the differentiating techniques used by the various lidar teams involved in the NDSC for the calculation of the ozone number density from the lidar signals. The exercise consisted of processing synthetic lidar signals computed from simple Rayleigh scattering and three initial ozone profiles. Two of these profiles contained perturbations in the low and the high stratosphere to test the vertical resolution of the various algorithms. For the unperturbed profiles the results of the simulations show the correct behavior of the lidar processing methods in the low and the middle stratosphere with biases of less than 1% with respect to the initial profile to as high as 30 km in most cases. In the upper stratosphere, significant biases reaching 10% at 45 km for most of the algorithms are obtained. This bias is due to the decrease in the signal-to-noise ratio with altitude, which makes it necessary to increase the number of points of the derivative low-pass filter used for data processing. As a consequence the response of the various retrieval algorithms to perturbations in the ozone profile is much better in the lower stratosphere than in the higher range. These results show the necessity of limiting the vertical smoothing in the ozone lidar retrieval algorithm and questions the ability of current lidar systems to detect long-term ozone trends above 40 km. Otherwise the simulations show in general a correct estimation of the ozone profile random error and, as shown by the tests involving the perturbed ozone profiles, some inconsistency in the estimation of the vertical resolution among the lidar teams involved in this experiment.

  6. Intercomparison of retrospective radon detectors.

    PubMed Central

    Field, R W; Steck, D J; Parkhurst, M A; Mahaffey, J A; Alavanja, M C

    1999-01-01

    We performed both a laboratory and a field intercomparison of two novel glass-based retrospective radon detectors previously used in major radon case-control studies performed in Missouri and Iowa. The new detectors estimate retrospective residential radon exposure from the accumulation of a long-lived radon decay product, (210)Pb, in glass. The detectors use track registration material in direct contact with glass surfaces to measure the alpha-emission of a (210)Pb-decay product, (210)Po. The detector's track density generation rate (tracks per square centimeter per hour) is proportional to the surface alpha-activity. In the absence of other strong sources of alpha-emission in the glass, the implanted surface alpha-activity should be proportional to the accumulated (210)Po, and hence to the cumulative radon gas exposure. The goals of the intercomparison were to a) perform collocated measurements using two different glass-based retrospective radon detectors in a controlled laboratory environment to compare their relative response to implanted polonium in the absence of environmental variation, b) perform collocated measurements using two different retrospective radon progeny detectors in a variety of residential settings to compare their detection of glass-implanted polonium activities, and c) examine the correlation between track density rates and contemporary radon gas concentrations. The laboratory results suggested that the materials and methods used by the studies produced similar track densities in detectors exposed to the same implanted (210)Po activity. The field phase of the intercomparison found excellent agreement between the track density rates for the two types of retrospective detectors. The correlation between the track density rates and direct contemporary radon concentration measurements was relatively high, considering that no adjustments were performed to account for either the residential depositional environment or glass surface type

  7. WOCE 1991 chlorofluorocarbon standard intercomparison report. Data report

    SciTech Connect

    Bullister, J.L.; Menzia, F.; Wisegarver, D.P.

    1993-07-01

    A chlorofluorocarbon (CFC) standard intercomparison study was done among ten laboratories involved in measurements of dissolved and atmospheric CFCs as part of the World Ocean Circulation Experiment (WOCE) and other programs. The goal of the study was to compare CFC calibration scales and to allow CFC data sets collected by the participating groups to be merged together more easily. One cyclinder was distributed to each participating laboratory for analysis and return to PMEL. Within the precision of the analytical techniques used at PMEL, the CFC-11 and CFC-12 concentrations in the cylinders remained uniform throughout the intercomparison exercise. The CFC-113 and carbon tetrachloride content of the cylinders remained relatively uniform in all but one of the cylinders analyzed. The CFC-11 concentrations reported by participating laboratories ranged from 258.8 to 275.6 parts-per-trillion (PPT). The reported CFC-12 concentrations ranged from 487.4 to 503.5 PPT. Two laboratories reported values for CFC-113, and only one laboratory reported a value for carbon tetrachloride. Details of the calibration techniques used by the ten participating laboratories are given in the Appendices of the report.

  8. Results of the Marine Ice Sheet Model Intercomparison Project, MISMIP

    NASA Astrophysics Data System (ADS)

    Pattyn, F.; Schoof, C.; Perichon, L.; Hindmarsh, R. C. A.; Bueler, E.; de Fleurian, B.; Durand, G.; Gagliardini, O.; Gladstone, R.; Goldberg, D.; Gudmundsson, G. H.; Huybrechts, P.; Lee, V.; Nick, F. M.; Payne, A. J.; Pollard, D.; Rybak, O.; Saito, F.; Vieli, A.

    2012-05-01

    Predictions of marine ice-sheet behaviour require models that are able to robustly simulate grounding line migration. We present results of an intercomparison exercise for marine ice-sheet models. Verification is effected by comparison with approximate analytical solutions for flux across the grounding line using simplified geometrical configurations (no lateral variations, no effects of lateral buttressing). Unique steady state grounding line positions exist for ice sheets on a downward sloping bed, while hysteresis occurs across an overdeepened bed, and stable steady state grounding line positions only occur on the downward-sloping sections. Models based on the shallow ice approximation, which does not resolve extensional stresses, do not reproduce the approximate analytical results unless appropriate parameterizations for ice flux are imposed at the grounding line. For extensional-stress resolving "shelfy stream" models, differences between model results were mainly due to the choice of spatial discretization. Moving grid methods were found to be the most accurate at capturing grounding line evolution, since they track the grounding line explicitly. Adaptive mesh refinement can further improve accuracy, including fixed grid models that generally perform poorly at coarse resolution. Fixed grid models, with nested grid representations of the grounding line, are able to generate accurate steady state positions, but can be inaccurate over transients. Only one full-Stokes model was included in the intercomparison, and consequently the accuracy of shelfy stream models as approximations of full-Stokes models remains to be determined in detail, especially during transients.

  9. Results of the Marine Ice Sheet Model Intercomparison Project, MISMIP

    NASA Astrophysics Data System (ADS)

    Pattyn, F.; Schoof, C.; Perichon, L.; Hindmarsh, R. C. A.; Bueler, E.; de Fleurian, B.; Durand, G.; Gagliardini, O.; Gladstone, R.; Goldberg, D.; Gudmundsson, G. H.; Lee, V.; Nick, F. M.; Payne, A. J.; Pollard, D.; Rybak, O.; Saito, F.; Vieli, A.

    2012-01-01

    Predictions of marine ice-sheet behaviour require models that are able to robustly simulate grounding line migration. We present results of an intercomparison exercise for marine ice-sheet models. Verification is effected by comparison with approximate analytical solutions for flux across the grounding line using simplified geometrical configurations (no lateral variations, no effects of lateral buttressing). Unique steady-state grounding line positions exist for ice sheets on a downward sloping bed, while hysteresis occurs across an overdeepened bed, and stable steady state grounding line positions only occur on the downward-sloping sections. Models based on the shallow ice approximation, which does not resolve extensional stresses, do not reproduce the approximate analytical results unless appropriate parameterizations for ice flux are imposed at the grounding line. For extensional-stress resolving "shelfy stream" models, differences between model results were mainly due to the choice of spatial discretization. Moving grid methods were found to be the most accurate at capturing grounding line evolution, since they track the grounding line explicitly. Adaptive mesh refinement can further improve accuracy, including in fixed-grid models that generally perform poorly at coarse resolution. Fixed grid models with nested grid representations of the grounding line are able to generate accurate steady-state positions, but can be inaccurate over transients. Only one full Stokes model was included in the intercomparison, and consequently the accuracy of shelfy stream models as approximations of full Stokes models remains to be determined in detail, especially during transients.

  10. Fifth personnel dosimetry intercomparison study

    SciTech Connect

    Sims, C.S.

    1980-02-01

    The fifth Personnel Dosimetry Intercomparison Study (PDIS) was conducted at the Oak Ridge National Laboratory's (ORNL) Dosimetry Applications Research (DOSAR) facility on March 20-22, 1979. This study is the latest PDIS in the continuing series started at the DOSAR facility in 1974. The PDIS is a three day study, typically in March, where personnel dosimeters are mailed to the DOSAR facility, exposed to a range of low-level neutron radiation doses (1 to 15 mSv or equivalently, 100 to 1500 mrem) and neutron-to-gamma ratios (1:1-10:1) using the Health Physics Research Reactor (HPRR) as the radiation source, and returned to the participants for evaluation. This report is a summary and analysis of the results reported by the various participants. The participants are able to intercompare their results with those of others who made dose measurements under identical experimental conditions.

  11. Results from the Second International Module Intercomparison

    SciTech Connect

    Rummel, S.; Anderberg, A.; Emery, K.

    2005-11-01

    The peak-watt rating is a primary indicator of PV performance. The peak power rating is the maximum electrical power that is produced when the PV device is continuously illuminated at 1000 Wm/sup-2/ total irradiance under International Electrotechnical Commission Standard 60904-2 reference spectrum, and 25 deg C cell temperature. Most manufacturers trace their peak-watt rating through calibrations performed at recognized terrestrial calibration facilities. Manufacturers typically perform intercomparisons among a set of their modules internally with other plants and among. Sometimes they have the same module measured at different calibration facilities to determine the differences in calibration. This intercomparison was to mimic this procedure and supply new thin film samples along with samples that could pose other problems. These intercomparisons sample the laboratories' everyday procedures better than a formal intercomparison where the laboratories' best procedures and data scrutiny are used.

  12. Blue irradiance intercomparison in the medical field

    NASA Astrophysics Data System (ADS)

    Ferreira, Antonio F. G.

    2012-10-01

    This work presents the results of a blue irradiance intercomparison among industrial laboratories of medical devices companies. This intercomparison aims to support the metrological issues of medical equipment manufactures regarding the blue irradiance infant phototherapy equipment requirements on the international standard IEC 60601-2-50:2000. The results showed a low agreement of participants' measurements according to normalized error criterion. The major explanation for this result is associated to an incorrect equipment choice and long recalibration period.

  13. Lidar Inter-Comparison Exercise Final Campaign Report

    SciTech Connect

    Protat, A; Young, S

    2015-02-01

    The objective of this field campaign was to evaluate the performance of the new Leosphere R-MAN 510 lidar, procured by the Australian Bureau of Meteorology, by testing it against the MicroPulse Lidar (MPL) and Raman lidars, at the Darwin Atmospheric Radiation Measurement (ARM) site. This lidar is an eye-safe (355 nm), turn-key mini Raman lidar, which allows for the detection of aerosols and cloud properties, and the retrieval of particulate extinction profiles. To accomplish this evaluation, the R-MAN 510 lidar has been operated at the Darwin ARM site, next to the MPL, Raman lidar, and Vaisala ceilometer (VCEIL) for three months (from 20 January 2013 to 20 April 2013) in order to collect a sufficient sample size for statistical comparisons.

  14. Lidar Inter-Comparison Exercise Final Campaign Report

    SciTech Connect

    Protat, Alain; Young, S.

    2015-02-01

    The objective of this IOP was to evaluate the performances of the new Leosphere R-MAN 510 lidar procured by the Australian Bureau of Meteorology, by testing it against the MPL and Raman lidars at the Darwin ARM site. This lidar is an eye-safe (355 nm), turn-key mini Raman lidar, which allows for the detection of aerosols and cloud properties, and the retrieval of particulate extinction profiles. To do so, the R-MAN 510 lidar has been operated at the Darwin ARM site, next to the MPL, Raman lidar, and Vaisala ceilometer for three months (from 20 January 2013 to 20 April 2013) in order to collect a good sample for statistical comparisons. The comparisons with the Raman lidar were not performed, since the Raman lidar attenuated backscatter and depolarization ratio product was not available. A new product has just been delivered to the ARM archive as a value-added product, hence this study will continue. Nevertheless we have developed software to match the different space and time resolutions of the other lidars and project the data onto a common grid to permit detailed comparison of the instruments’ performance and an enhanced analysis of clouds and aerosols through the use of composite data products, like the ratios of attenuated backscatters, attenuated scattering ratios and depolarization ratios. Comparisons between the MPL and R-MAN510 lidar data exhibit large differences in total attenuated backscatter at 355 and 532 nm, attenuated scattering ratios, and aerosol volume depolarization ratios. Differences in attenuated backscatter result mainly from the different relative contributions of scattering from molecules and particles at the different wavelengths, but there are some intriguing differences that will require further investigations. The differences in volume depolarization ratios are due to the much larger contribution of molecular returns to the volume depolarization ratio (5 times larger at 355 nm than at 532 nm). The R-MAN510 lidar is also found to be much less sensitive to daylight solar background illumination, which is greater at the visible wavelength than in the UV.

  15. Intercomparison of MAX-DOAS NO2 retrieval algorithms

    NASA Astrophysics Data System (ADS)

    Peters, Enno; Pinardi, Gaia; Bösch, Tim; Wittrock, Folkard; Richter, Andreas; Burrows, John P.; Van Roozendael, Michel; Piters, Ankie; Wagner, Thomas; Drosoglou, Theano; Bais, Alkis; Wang, Shanshan; Saiz-Lopez, Alfonso

    2016-04-01

    Ground-based Multi-Axis Differential Optical Absorption Spectroscopy (MAX-DOAS) measurements are a powerful method for monitoring of atmospheric composition in an automated way. The number of instruments and sites operated has been rapidly increasing over the last years. However, integrating the measurements from all these instruments into a consistent data set necessitates careful homogenization of measurements and data retrieval procedures. For this reason, several MAX-DOAS intercomparison campaigns have been carried out in the last years. Mostly, slant columns measured by different instruments and retrieved by different software were intercompared, i.e. observed differences were potentially caused by both, the instrument and/or the retrieval. In contrast, the approach presented here is a pure intercomparison of MAX-DOAS retrievals. In total, 16 international groups and institutes working in the field of MAX-DOAS participated. The work was performed as part of the EU-funded QA4ECV project. The intercomparison exercise is based on data recorded by the IUP-Bremen MAX-DOAS instrument during the MAD-CAT campaign (Multi-Axis DOAS comparison campaign for Aerosols and Trace gases), which was carried out at the Max-Planck-Institute of Chemistry in Mainz, Germany, in summer 2013. Each group participating in the exercise presented here performed MAX-DOAS fits using their own retrieval software but common input (IUP-Bremen spectra, same cross-sections, and same fit settings). The resulting slant columns show in general an excellent agreement (correlation coefficient > 99.9%). Surprisingly, the correlation is substantially smaller when using sequential Fraunhofer reference spectra instead of a noon reference indicating that groups calculate the sequential reference differently. Further differences were found to arise from treatment of the slit function and subsequent convolution of cross-sections as well as from wavelength calibration. The results indicate overall a high

  16. INTERCOMPARISON OF OPTICAL REMOTE SENSING SYSTEMS FOR ROADSIDE MEASUREMENTS

    EPA Science Inventory

    The presentation describes results of an intercomparison of three optical remote sensing systems for measurements of nitric oxide emitted from passenger cars and light-duty trucks. The intercomparison included a standards comparison to establish comparability of standards, follo...

  17. An intercomparison of nitric oxide measurement techniques

    NASA Technical Reports Server (NTRS)

    Hoell, J. M., Jr.; Gregory, G. L.; Mcdougal, D. S.; Carroll, M. A.; Mcfarland, M.; Ridley, B. A.; Davis, D. D.; Bradshaw, J.; Rodgers, M. O.; Torres, A. L.

    1985-01-01

    Results from an intercomparison of techniques to measure tropospheric levels of nitric oxide (NO) are discussed. The intercomparison was part of the National Aeronautics and Space Administration's Global Tropospheric Experiment and was conducted at Wallops Island, VA, in July 1983. Instruments intercompared included a laser-induced fluorescence system and two chemiluminescence instruments. The intercomparisons were performed with ambient air at NO mixing ratios ranging from 10 to 60 pptv and NO-enriched ambient air at mixing ratios from 20 to 170 pptv. All instruments sampled from a common manifold. The techniques exhibited a high degree of correlation among themselves and with changes in the NO mixing ratio. Agreement among the three techniques was placed at approximately + or - 30 percent. Within this level of agreement, no artifacts or species interferences were identified.

  18. Desert Dust Satellite Retrieval Intercomparison

    NASA Technical Reports Server (NTRS)

    Carboni, E.; Thomas, G. E.; Sayer, A. M.; Siddans, R.; Poulsen, C. A.; Grainger, R. G.; Ahn, C.; Antoine, D.; Bevan, S.; Braak, R.; Brindley, H.; DeSouza-Mchado, S.; Deuze, J. L.; Diner, D.; Ducos, F.; Grey, W.; Hsu, C.; Kalashnikova, O. V.; Kahn, R.; North, P. R. J.; Salustro, C.; Smith, A.; Tanre, D.; Torres, O.; Veihelmann, B.

    2012-01-01

    This work provides a comparison of satellite retrievals of Saharan desert dust aerosol optical depth (AOD) during a strong dust event through March 2006. In this event, a large dust plume was transported over desert, vegetated, and ocean surfaces. The aim is to identify and understand the differences between current algorithms, and hence improve future retrieval algorithms. The satellite instruments considered are AATSR, AIRS, MERIS, MISR, MODIS, OMI, POLDER, and SEVIRI. An interesting aspect is that the different algorithms make use of different instrument characteristics to obtain retrievals over bright surfaces. These include multi-angle approaches (MISR, AATSR), polarisation measurements (POLDER), single-view approaches using solar wavelengths (OMI, MODIS), and the thermal infrared spectral region (SEVIRI, AIRS). Differences between instruments, together with the comparison of different retrieval algorithms applied to measurements from the same instrument, provide a unique insight into the performance and characteristics of the various techniques employed. As well as the intercomparison between different satellite products, the AODs have also been compared to co-located AERONET data. Despite the fact that the agreement between satellite and AERONET AODs is reasonably good for all of the datasets, there are significant differences between them when compared to each other, especially over land. These differences are partially due to differences in the algorithms, such as as20 sumptions about aerosol model and surface properties. However, in this comparison of spatially and temporally averaged data, at least as significant as these differences are sampling issues related to the actual footprint of each instrument on the heterogeneous aerosol field, cloud identification and the quality control flags of each dataset.

  19. Intercomparison of atmospheric dispersion models

    NASA Astrophysics Data System (ADS)

    Caputo, Marcelo; Giménez, Marcelo; Schlamp, Miguel

    An intercomparison between Gaussian, Gaussian segmented plumes and Lagrangian codes is presented. The codes chosen for the simulation of a gaseous emission under real meteorological conditions were AERMOD, HPDM, PCCOSYMA and HYSPLIT. The emission source was located at 37.35°N and 78.24°W in a flat terrain. The meteorological data were obtained from RAMS code output. The AERMOD and HPDM meteorological preprocessors results were analyzed. The main differences found are originated in the sensible heat flux (SHTF) and u* (friction velocity) computation, whose values impact directly on the Monin-Obukov length and mixing height calculation. These differences and the strong dependence of the results on them indicate that more development should still be done in order to improve the algorithms for the meteorological variables calculations, mainly during stable conditions. A more realistic description is performed by the segmented Gaussian plume model (PCCOSYMA) respect to the Gaussian ones (AERMOD, HPDM) because it limits the plume length along the wind direction. It also predicts reasonably well the contaminant cloud rotation respect to the Lagrangian code (HYSPLIT) as no major difference between the wind field and the wind at the source location is present in the analyzed case. During the stable hours, HPDM calculates the most stable situation and the lowest mixing heights. Because of this there is a considerable discrepancy in the maximum ground level concentration respect to the other codes. While during the unstable hours HPDM calculates the most unstable situation, nevertheless the maximum ground level concentrations predicted by all the Gaussian and Lagrangian codes are comparable.

  20. An intercomparison of airborne nitric acid measurements

    NASA Astrophysics Data System (ADS)

    Gregory, G. L.; Hoell, J. M.; Huebert, B. J.; van Bramer, S. E.; Lebel, P. J.; Vay, S. A.; Marinaro, R. M.; Schiff, H. I.; Hastie, D. R.; Mackay, G. I.; Karecki, D. R.

    1990-06-01

    Results from an airborne intercomparison of techniques to measure tropospheric levels of nitric acid are discussed. The intercomparison was part of the National Aeronautics and Space Administration's Global Tropospheric Experiment and was conducted during the summer of 1986. Instruments intercompared included a denuder tube collection system (DENUDER) with chemiluminescent detection, a niylon filter collection system (FILTER) with ion chromatography detection, and a tunable diode laser (TDLAS) multipath absorption system. Intercomparison of investigators' calibration standards were also performed as part of the test protocol. While results were somewhat "soft" and data sparse, these tests suggested that the TDLAS measurements might be high compared to the other techniques. Airborne intercomparisons were conducted predominately in the free troposphere and included encounters with marine and continental air masses. While the intercomparisons included mixing ratios to 1000 parts per trillion by volume (pptv), the majority of the results were for mixing ratios of <300 pptv. The TDLAS participated in an intercomparison of NO2 instruments (major focus) that was also conducted during the same flights. As a result the TDLAS data set is limited. Further, a significant fraction of the nitric acid measurements were below the TDLAS detection limit (75 pptv as configured for these tests). While the lack of simultaneous measurements from the three instruments limits the conclusions that can be drawn, it is clear that there can be substantial disagreement among the three techniques, even at mixing ratios above their respective detection limits. Equally clear is that at mixing ratios below 150 pptv there is very little correlation between their results. Based on these observations, an overall conclusion from the intercomparison is that none of the HNO3 techniques can be identified to unambiguously (e.g., 20% accuracy) provide measurements of HNO3 at levels often encountered in the

  1. Intercomparison and intercalibration of passive/active radon and active radon progeny instruments and methods in North America

    SciTech Connect

    George, A.C.; Tu, Keng W.

    1993-06-01

    An intercomparison and intercalibration exercise for radon and radon progeny measurements made with active and passive instruments was held at EML from October 22--30,1992. Twenty-five participants submitted 96 passive integrating devices, eight active devices for radon, and seven integrating devices for potential alpha energy concentration (PAEC). In addition, 40 grab samples for radon progeny analysis were taken by five groups that participated in person during the intercomparison. The results reported to EML indicate that the majority of the participants (70%) obtained mean results within 10% of the EML reference value. Although the instruments used in this exercise are based on different principles of collection and detection, they all appear reliable. However, in some instances there seemed to be some minor problems with quality control and calibration bias. Also, the large counting errors for the PAEC experienced by some of the participants can be minimized by using higher sampling air flow rates without sacrificing instrument portability.

  2. Indoor and Outdoor Spectroradiometer Intercomparison for Spectral Irradiance Measurement

    SciTech Connect

    Habte, A.; Andreas, A.; Ottoson, L.; Gueymard, C.; Fedor, G.; Fowler, S.; Peterson, J.; Naranen, R.; Kobashi, T.; Akiyama, A.; Takagi, S.

    2014-05-01

    This report details the global spectral irradiance intercomparison using spectroradiometers that was organized by the National Renewable Energy Laboratory's Solar Radiation Research Laboratory. The intercomparison was performed both indoors and outdoors on September 17, 2013. Five laboratories participated in the intercomparison using 10 spectroradiometers, and a coordinated measurement setup and a common platform were employed to compare spectral irradiances under both indoor and outdoor conditions. The intercomparison aimed to understand the performance of the different spectroradiometers and to share knowledge in making spectral irradiance measurements. This intercomparison was the first of its kind in the United States.

  3. SPARC Reanalysis Intercomparison Project (S-RIP)

    NASA Astrophysics Data System (ADS)

    Fujiwara, M.; Long, C. S.

    2014-12-01

    The middle atmosphere and climate community use reanalyses widely to understand atmospheric processes and variability in the middle atmosphere, to validate climate models, and, potentially, for trend analysis. Yet different reanalyses give different results for the same diagnostic. There is thus a need for a coordinated reanalysis intercomparison project that shall start a comprehensive activity to compare all appropriate reanalysis data sets for key diagnostics to help understand the causes of differences and to use the results to provide guidance on appropriate usage of various reanalysis products in scientific studies. In addition, the reanalysis community will benefit from coordinated user feedback, which can lead to improvements in the next generation of reanalysis products. The Stratosphere-troposphere Processes And their Role in Climate (SPARC) Reanalysis Intercomparison Project (S-RIP) is a SPARC activity that was proposed in 2012 and approved in 2014. The goals of S-RIP are: (1) to create a communication platform between the SPARC community and the reanalysis centers; (2) to understand current reanalysis products and to contribute to future reanalysis improvements in the middle atmosphere region; and (3) to write up the results of the reanalysis intercomparison in peer reviewed papers and a SPARC report. The project duration is from 2013 to 2018. In the presentation, an overview of the project is made and some early intercomparison results are discussed.

  4. GDAT intercomparison exercice on CFCs and SF6 tracers for groundwater dating

    NASA Astrophysics Data System (ADS)

    Labasque, Thierry; vergnaud, virginie

    2013-04-01

    GDAT intercomparison exercice on CFCs and SF6 tracers for groundwater dating Labasque T. Géosciences Rennes, Université Rennes1-CNRS, Rennes, France GDAT-participants for CFCs and SF6 comparisons: Aquilina L., Vergnaud V., Geosciences Rennes, France; Goody D., BGS Wallingford, UK; Leaney F., Suckow A., CSIRO, Australia; Oster H, Spurentofflabor, Germany; Han L., Hillegonds D, Matsumoto T., IAEA, Austria; Aeschbach-Hertig W., Freund F., Schneider T., Heidelberg, Germany; Yoon Y., Kigam, Corea; Busenberg E., Casile J., USGS Reston Lab, USA; Rosanski K., Bartysel J., AGH, Poland; Sliwka I., Bielewski J., INP, Poland; Rigby A., Solomon K;, University of Utah, USA; Barbecot F., IDES, France. Two intercomparison exercises have been carried out in 2012 by the hydrogeochemist community : Fontainebleau sandy aquifer (January 2012) and Betton fractured shists aquifer (October 2012). Environmental tracers devoted to groundwater dating were compared during these experiments. These methods are very sensitive and need a great analytical practice to obtain accurate results. The GDAT exercise was designed in order to compare methods and analytical protocols. All the participants sampled groundwater from the same boreholes at the same time using similar sampling methods, and analysed similar environmental tracers using for each laboratory its own analytical protocol. We here present CFCs and SF6 results obtained on the Fontainebleau aquifer and on the Betton aquifer. The first one shows quite "old" CFC waters and the second one "younger" CFCs waters. The intercomparison exercise brought together 31 laboratories from 14 countries including 12 laboratories for CFCs analysis and 11 for SF6 analysis. Results show good agreement for most of the laboratories with apparent uncertainties less than 3 years on the quite "old" CFCs waters. The major uncertainty source results from sampling and storage methods.

  5. Questionable Exercises.

    ERIC Educational Resources Information Center

    Liemohn, Wendell; Haydu, Traci; Phillips, Dawn

    1999-01-01

    This publication presents general guidelines for exercise prescription that have an anatomical basis but also consider the exerciser's ability to do the exercise correctly. It reviews various common questionable exercises, explaining how some exercises, especially those designed for flexibility and muscle fitness, can cause harm. Safer…

  6. Intercomparison of aerosol extinction profiles retrieved from MAX-DOAS measurements

    NASA Astrophysics Data System (ADS)

    Frieß, U.; Klein Baltink, H.; Beirle, S.; Clémer, K.; Hendrick, F.; Henzing, B.; Irie, H.; de Leeuw, G.; Li, A.; Moerman, M. M.; van Roozendael, M.; Shaiganfar, R.; Wagner, T.; Wang, Y.; Xie, P.; Yilmaz, S.; Zieger, P.

    2016-07-01

    A first direct intercomparison of aerosol vertical profiles from Multi-Axis Differential Optical Absorption Spectroscopy (MAX-DOAS) observations, performed during the Cabauw Intercomparison Campaign of Nitrogen Dioxide measuring Instruments (CINDI) in summer 2009, is presented. Five out of 14 participants of the CINDI campaign reported aerosol extinction profiles and aerosol optical thickness (AOT) as deduced from observations of differential slant column densities of the oxygen collision complex (O4) at different elevation angles. Aerosol extinction vertical profiles and AOT are compared to backscatter profiles from a ceilometer instrument and to sun photometer measurements, respectively. Furthermore, the near-surface aerosol extinction coefficient is compared to in situ measurements of a humidity-controlled nephelometer and dry aerosol absorption measurements. The participants of this intercomparison exercise use different approaches for the retrieval of aerosol information, including the retrieval of the full vertical profile using optimal estimation and a parametrised approach with a prescribed profile shape. Despite these large conceptual differences, and also differences in the wavelength of the observed O4 absorption band, good agreement in terms of the vertical structure of aerosols within the boundary layer is achieved between the aerosol extinction profiles retrieved by the different groups and the backscatter profiles observed by the ceilometer instrument. AOTs from MAX-DOAS and sun photometer show a good correlation (R>0.8), but all participants systematically underestimate the AOT. Substantial differences between the near-surface aerosol extinction from MAX-DOAS and from the humidified nephelometer remain largely unresolved.

  7. Satellite Derived Volcanic Ash Product Inter-Comparison in Support to SCOPE-Nowcasting

    NASA Astrophysics Data System (ADS)

    Siddans, Richard; Thomas, Gareth; Pavolonis, Mike; Bojinski, Stephan

    2016-04-01

    In support of aeronautical meteorological services, WMO organized a satellite-based volcanic ash retrieval algorithm inter-comparison activity, to improve the consistency of quantitative volcanic ash products from satellites, under the Sustained, Coordinated Processing of Environmental Satellite Data for Nowcasting (SCOPEe Nowcasting) initiative (http:/ jwww.wmo.int/pagesjprogjsatjscopee nowcasting_en.php). The aims of the intercomparison were as follows: 1. Select cases (Sarychev Peak 2009, Eyjafyallajökull 2010, Grimsvötn 2011, Puyehue-Cordón Caulle 2011, Kirishimayama 2011, Kelut 2014), and quantify the differences between satellite-derived volcanic ash cloud properties derived from different techniques and sensors; 2. Establish a basic validation protocol for satellite-derived volcanic ash cloud properties; 3. Document the strengths and weaknesses of different remote sensing approaches as a function of satellite sensor; 4. Standardize the units and quality flags associated with volcanic cloud geophysical parameters; 5. Provide recommendations to Volcanic Ash Advisory Centers (VAACs) and other users on how to best to utilize quantitative satellite products in operations; 6. Create a "road map" for future volcanic ash related scientific developments and inter-comparison/validation activities that can also be applied to SO2 clouds and emergent volcanic clouds. Volcanic ash satellite remote sensing experts from operational and research organizations were encouraged to participate in the inter-comparison activity, to establish the plans for the inter-comparison and to submit data sets. RAL was contracted by EUMETSAT to perform a systematic inter-comparison of all submitted datasets and results were reported at the WMO International Volcanic Ash Inter-comparison Meeting to held on 29 June - 2 July 2015 in Madison, WI, USA (http:/ /cimss.ssec.wisc.edujmeetings/vol_ash14). 26 different data sets were submitted, from a range of passive imagers and spectrometers and

  8. Intercomparison of Operational Ocean Forecasting Systems in the framework of GODAE

    NASA Astrophysics Data System (ADS)

    Hernandez, F.

    2009-04-01

    One of the main benefits of the GODAE 10-year activity is the implementation of ocean forecasting systems in several countries. In 2008, several systems are operated routinely, at global or basin scale. Among them, the BLUElink (Australia), HYCOM (USA), MOVE/MRI.COM (Japan), Mercator (France), FOAM (United Kingdom), TOPAZ (Norway) and C-NOOFS (Canada) systems offered to demonstrate their operational feasibility by performing an intercomparison exercise during a three months period (February to April 2008). The objectives were: a) to show that operational ocean forecasting systems are operated routinely in different countries, and that they can interact; b) to perform in a similar way a scientific validation aimed to assess the quality of the ocean estimates, the performance, and forecasting capabilities of each system; and c) to learn from this intercomparison exercise to increase inter-operability and collaboration in real time. The intercomparison relies on the assessment strategy developed for the EU MERSEA project, where diagnostics over the global ocean have been revisited by the GODAE contributors. This approach, based on metrics, allow for each system: a) to verify if ocean estimates are consistent with the current general knowledge of the dynamics; and b) to evaluate the accuracy of delivered products, compared to space and in-situ observations. Using the same diagnostics also allows one to intercompare the results from each system consistently. Water masses and general circulation description by the different systems are consistent with WOA05 Levitus climatology. The large scale dynamics (tropical, subtropical and subpolar gyres ) are also correctly reproduced. At short scales, benefit of high resolution systems can be evidenced on the turbulent eddy field, in particular when compared to eddy kinetic energy deduced from satellite altimetry of drifter observations. Comparisons to high resolution SST products show some discrepancies on ocean surface

  9. An intercomparison of airborne nitric acid measurements

    SciTech Connect

    Gregory, G.L.; Hoell, J.M. Jr.; LeBel, P.J.; Vay, S.A. ); Huebert, B.J. ); Van Bramer, S.E. ); Marinaro, R.M. ); Schiff, H.I.; Hastie, D.R. ); Mackay, G.I.; Karecki, D.R. )

    1990-06-20

    Instruments intercompared included a denuder tube collection system (DENUDER) with chemiluminescent detection, a nylon filter collection system (FILTER) with ion chromatography detection, and a tunable diode laser (TDLAS) multipath absorption system. While results were somewhat soft and data sparse, these tests suggested that the TDLAS measurements might be high compared to the other techniques. Airborne intercomparisons were conducted predominantly in the free troposphere and included encounters with marine and continental air masses. While the intercomparisons included mixing ratios to 1,000 parts per trillion by volume (pptv), the majority of the results were for mixing ratios of <300 pptv. While the lack of simultaneous measurements from the three instruments limits the conclusions that can be drawn, it is clear that there can be substantial disagreement among the three techniques, even at mixing ratios above their respective detection limits. Equally clear is that at mixing ratios below 150 pptv there is very little correlation between their results. Based on these observations, an overall conclusion from the intercomparison is that none of the HNO{sub 3} techniques can be identified to unambiguously (e.g., 20% accuracy) provide measurements of HNO{sub 3} at levels often encountered in the free troposphere (e.g., 100 pptv). However, at the more elevated levels of HNO{sub 3} (e.g., >150 pptv), both the FILTER and DENUDER techniques reported the same levels of nitric acid, while as suggested by the results from the standards intercomparison, the TDLAS reported higher nitric acid values than the other two techniques.

  10. Results from 2010 Caliban Criticality Dosimetry Intercomparison

    SciTech Connect

    Veinot, K. G.

    2011-10-12

    The external dosimetry program participated in a criticality dosimetry intercomparison conducted at the Caliban facility in Valduc, France in 2010. Representatives from the dosimetry and instrumentation groups were present during testing which included irradiations of whole-body beta/gamma (HBGT) and neutron thermoluminescent dosimeters (TLDs), a fixed nuclear accident dosimeter (FNAD), electronic alarming dosimeters, and a humanoid phantom filled with reference man concentrations of sodium. This report reviews the testing procedures, preparations, irradiations, and presents results of the tests.

  11. The 1991 WMO ozone sonde intercomparison

    NASA Technical Reports Server (NTRS)

    Kerr, James B.; Mcelroy, C. Thomas; Fast, Hans; Oltmans, Sam J.; Lathrop, Jeff A.; Kyro, Esko; Paukkunen, Ari; Claude, Hans J.; Kohler, Ulf; Sreedharan, C. R.

    1994-01-01

    The WMO ozone sonde intercomparison was held at Vanscoy, Saskatchewan from May 13 to May 24, 1991. The purpose of the intercomparison is to evaluate the performance of various ozone sonde types used operationally in the Global Ozone Observing System and to ensure that the accuracy and precision of the measurements are sufficient to detect long-term trends in stratospheric ozone. The intercomparison was sponsored by WMO and hosted by the Atmospheric Environment Service (AES) of Canada. It was attended by scientists from six countries: Canada, Finland, Germany, India, Japan and USA. A total of 10 balloon payloads were launched each carrying 7 or 8 sondes for a total of 67 successful ozone sonde flights. The payloads were carried to altitudes between 35 and 40 km where the flights terminated by balloon burst. Results of the profile measurements made during the series of the profile measurements made during the series of flight are used to determine statistically meaningful evaluations of the different sonde types. A description of the payload and the different ozone sondes is given. Preliminary results of the profile measurements and an evaluation of the performance of the sonde types are presented.

  12. Inter-comparison of subglacial hydrological models

    NASA Astrophysics Data System (ADS)

    de Fleurian, Basile; Werder, Mauro

    2016-04-01

    The recent emergence of a number of subglacial hydrological models allows us to obtain theoretical insights on basal processes; for instance on the coupling between water pressure and the sliding of glaciers. In ice-flow models, it is relatively clear what the simulated physics ought to be. Conversely, the physical processes incorporated into subglacial hydrology models are diverse as it is yet unclear which ones are of relevance for a particular setting. An inter-comparison of hydrology models will therefore need a somewhat different approach to the one used in the many ice-flow model inter-comparisons (EISMINT, ISMIP, etc.). Here, we present a set of experiments that will allow the comparison of the behavior of different hydrology models. The design of the benchmark aims at allowing the participation of a wide range of models based on different physical approaches. We aim at evaluating the models with a focus on the effective pressure which has the most impact on the dynamics of glaciers. The aim of this inter-comparison is to provide modellers with the necessary data to make an informed decision on which subglacial hydrology model to use for a particular study.

  13. The role of inter-comparisons in radiocarbon quality assurance

    NASA Astrophysics Data System (ADS)

    Scott, Marian; Cook, Gordon; Naysmith, Philip

    2016-04-01

    Radiocarbon dating is used widely in many geochronology projects as a basis for the creation and testing of chronological constructs. Radiocarbon measurements are by their nature complex and the degree of sample pre-treatment varies considerably depending on the material. Within the UK and Europe, there are a number of well-established laboratories and increasingly, scientists are not just commissioning new dates, but also using statistical modelling of assemblages of dates, perhaps measured in different laboratories, to provide formal date estimates for their investigations. The issue of comparability of measurements (and thus bias, accuracy and precision of measurement) from the diverse laboratories is one which has been the focus of some attention both within the 14C community and the wider user communities for some time. As a result of this but also as part of laboratory benchmarking and quality assurance, the 14C community has undertaken a wide-scale, far-reaching and evolving programme of inter-comparisons, to the benefit of laboratories and users alike. This paper presents the results from the most recent exercise SIRI. The objectives of SIRI included, through choice of material, to contribute to the discussion concerning laboratory offsets and error multipliers in the context of IntCal (the International Calibration Programme) and to gain a better understanding of differences in background derived from a range of infinite age material types.

  14. Intercomparison of radiation protection instrumentation in a pulsed neutron field

    NASA Astrophysics Data System (ADS)

    Caresana, M.; Denker, A.; Esposito, A.; Ferrarini, M.; Golnik, N.; Hohmann, E.; Leuschner, A.; Luszik-Bhadra, M.; Manessi, G.; Mayer, S.; Ott, K.; Röhrich, J.; Silari, M.; Trompier, F.; Volnhals, M.; Wielunski, M.

    2014-02-01

    In the framework of the EURADOS working group 11, an intercomparison of active neutron survey meters was performed in a pulsed neutron field (PNF). The aim of the exercise was to evaluate the performances of various neutron instruments, including commercially available rem-counters, personal dosemeters and instrument prototypes. The measurements took place at the cyclotron of the Helmholtz-Zentrum Berlin für Materialien und Energie GmbH. The cyclotron is routinely used for proton therapy of ocular tumours, but an experimental area is also available. For the therapy the machine accelerates protons to 68 MeV. The interaction of the proton beam with a thick tungsten target produces a neutron field with energy up to about 60 MeV. One interesting feature of the cyclotron is that the beam can be delivered in bursts, with the possibility to modify in a simple and flexible way the burst length and the ion current. Through this possibility one can obtain radiation bursts of variable duration and intensity. All instruments were placed in a reference position and irradiated with neutrons delivered in bursts of different intensity. The analysis of the instrument response as a function of the burst charge (the total electric charge of the protons in the burst shot onto the tungsten target) permitted to assess for each device the dose underestimation due to the time structure of the radiation field. The personal neutron dosemeters were exposed on a standard PMMA slab phantom and the response linearity was evaluated.

  15. Exercise Prescription.

    ERIC Educational Resources Information Center

    Ribisl, Paul M.

    If exercise programs are to become effective in producing the desired results, then the correct exercise prescription must be applied. Four variables should be controlled in the prescription of exercise: (a) type of activity, (b) intensity, (c) duration, and (d) frequency. The long-term prescription of exercise involves the use of a (a) starter…

  16. Design of the MISMIP+, ISOMIP+, and MISOMIP ice-sheet, ocean, and coupled ice sheet-ocean intercomparison projects

    NASA Astrophysics Data System (ADS)

    Asay-Davis, Xylar; Cornford, Stephen; Martin, Daniel; Gudmundsson, Hilmar; Holland, David; Holland, Denise

    2015-04-01

    The MISMIP and MISMIP3D marine ice sheet model intercomparison exercises have become popular benchmarks, and several modeling groups have used them to show how their models compare to both analytical results and other models. Similarly, the ISOMIP (Ice Shelf-Ocean Model Intercomparison Project) experiments have acted as a proving ground for ocean models with sub-ice-shelf cavities.As coupled ice sheet-ocean models become available, an updated set of benchmark experiments is needed. To this end, we propose sequel experiments, MISMIP+ and ISOMIP+, with an end goal of coupling the two in a third intercomparison exercise, MISOMIP (the Marine Ice Sheet-Ocean Model Intercomparison Project). Like MISMIP3D, the MISMIP+ experiments take place in an idealized, three-dimensional setting and compare full 3D (Stokes) and reduced, hydrostatic models. Unlike the earlier exercises, the primary focus will be the response of models to sub-shelf melting. The chosen configuration features an ice shelf that experiences substantial lateral shear and buttresses the upstream ice, and so is well suited to melting experiments. Differences between the steady states of each model are minor compared to the response to melt-rate perturbations, reflecting typical real-world applications where parameters are chosen so that the initial states of all models tend to match observations. The three ISOMIP+ experiments have been designed to to make use of the same bedrock topography as MISMIP+ and using ice-shelf geometries from MISMIP+ results produced by the BISICLES ice-sheet model. The first two experiments use static ice-shelf geometries to simulate the evolution of ocean dynamics and resulting melt rates to a quasi-steady state when far-field forcing changes in either from cold to warm or from warm to cold states. The third experiment prescribes 200 years of dynamic ice-shelf geometry (with both retreating and advancing ice) based on a BISICLES simulation along with similar flips between warm and

  17. The ENEA criticality accident dosimetry system: a contribution to the 2002 international intercomparison at the SILENE reactor.

    PubMed

    Gualdrini, G; Bedogni, R; Fantuzzi, E; Mariotti, F

    2004-01-01

    The present paper summarises the activity carried out at the ENEA Radiation Protection Institute for updating the methodologies employed for the evaluation of the neutron and photon dose to the exposed workers in case of a criticality accident, in the framework of the 'International Intercomparison of Criticality Accident Dosimetry Systems' (Silène reactor, IRSN-CEA-Valduc June 2002). The evaluation of the neutron spectra and the neutron dosimetric quantities relies on activation detectors and on unfolding algorithms. Thermoluminescent detectors are employed for the gamma dose measurement. The work is aimed at accurately characterising the measurement system and, at the same time, testing the algorithms. Useful spectral information were included, based on Monte Carlo simulations, to take into account the potential accident scenarios of practical interest. All along this exercise intercomparison a particular attention was devoted to the 'traceability' of all the experimental and computational parameters and therefore, aimed at an easy treatment by the user. PMID:15353692

  18. A US intercomparison of Josephson array voltage standards

    SciTech Connect

    Rodriguez, K.M.; Huntley, L.

    1994-12-31

    Qualification of intrinsic standards is a problem for laboratory accreditation systems. Accredited laboratories must demonstrate that their intrinsic standards actually provide the accuracy claimed. Ten standards laboratories have participated in an intercomparison of their 10 Volt Josephson Array Standards. The intercomparison program is described and results are presented.

  19. DOE Radiological Calibrations Intercomparison Program: Results of fiscal year 1987

    SciTech Connect

    Cummings, F.M.; McDonald, J.C.

    1988-06-01

    This report presents the FY 1987 results of the radiological calibrations intercomparison program. The intercomparison operation is discussed, and the equipment is described, particularly the instrument set, the beta source set, and relevant calculations. Solutions to problems and improvements in the program are suggested, and conclusions are then introduced. 9 refs., 3 figs., 8 tabs.

  20. Stratospheric Ozone Intercomparison Campaign (STOIC) 1989: Overview

    NASA Technical Reports Server (NTRS)

    Margitan, J. J.; Barnes, R. A.; Brothers, G. B.; Butler, J.; Burris, J.; Connor, B. J.; Ferrare, R. A.; Kerr, J. B.; Komhyr, W. D.; McCormick, M. P.; McDermid, I. S.; McElroy, C. T.; McGee, T. J.; Miller, A. J.; Owens, M.; Parrish, A. D.; Parsons, C. L.; Torres, A. L.; Tsou, J. J.; Walsh, T. D.

    1995-01-01

    The NASA Upper Atmosphere Research Program organized a Stratospheric Ozone Intercomparison Campaign (STOIC) held in July-August 1989 at the Table Mountain Facility (TMF) of the Jet Propulsion Laboratory (JPL). The primary instruments participating in this campaign were several that had been developed by NASA for the Network for the Detection of Stratospheric Change: the JPL ozone lidar at TMF, the Goddard Space Flight Center trailer-mounted ozone lidar which was moved to TMF for this comparison, and the Millitech/LaRC microwave radiometer. To assess the performance of these new instruments, a validation/intercomparison campaign was undertaken using established techniques: balloon ozonesondes launched by personnel from the Wallops Flight Facility and from NOAA Geophysical Monitoring for Climate Change (GMCC) (now Climate Monitoring and Diagnostics Laboratory), a NOAA GMCC Dobson spectrophotometer, and a Brewer spectrometer from the Atmospheric Environment Service of Canada, both being used for column as well as Umkehr profile retrievals. All of these instruments were located at TMF and measurements were made as close together in time as possible to minimize atmospheric variability as a factor in the comparisons. Daytime rocket measurements of ozone were made by Wallops Flight Facility personnel using ROCOZ-A instruments launched from San Nicholas Island. The entire campaign was conducted as a blind intercomparison, with the investigators not seeing each others data until all data had been submitted to a referee and archived at the end of the 2-week period (July 20 to August 2, 1989). Satellite data were also obtained from the Stratospheric Aerosol and Gas Experiment (SAGE 2) aboard the Earth Radiation Budget Satellite and the Total Ozone Mapping Spectrometer (TOMS) aboard Nimbus 7. An examination of the data has found excellent agreement among the techniques, especially in the 20- to 40-km range. As expected, there was little atmospheric variability during the

  1. VLBI Digital-Backend Intercomparison Test Report

    NASA Technical Reports Server (NTRS)

    Whitney, Alan; Beaudoin, Christopher; Cappallo, Roger; Niell, Arthur; Petrachenko, Bill; Ruszczyk, Chester A.; Titus, Mike

    2013-01-01

    Issues related to digital-backend (DBE) systems can be difficult to evaluate in either local tests or actual VLBI experiments. The 2nd DBE intercomparison workshop at Haystack Observatory on 25-26 October 2012 provided a forum to explicitly address validation and interoperability issues among independent global developers of DBE equipment. This special report discusses the workshop. It identifies DBE systems that were tested at the workshop, describes the test objectives and procedures, and reports and discusses the results of the testing.

  2. Compulsive Exercise

    MedlinePlus

    ... of power to help them cope with low self-esteem. Although compulsive exercising doesn't have to accompany ... a downward spiral of negative thinking and low self-esteem. continue Why Is Exercising Too Much a Bad ...

  3. Exercise & Sleep

    MedlinePlus

    ... on. Feature: Back to School, the Healthy Way Exercise & Sleep Past Issues / Fall 2012 Table of Contents ... helps kids. Photo: iStock 6 "Bests" About Kids' Exercise At least one hour of physical activity a ...

  4. 3H And 90Sr In Urine Radiobioassay Intercomparison Results From The Intercomparison Studies Program At Oak Ridge National Laboratory: Statistical Analysis Of Laboratory Performance

    SciTech Connect

    Bores, Norman; Schultz, Michael K

    2009-01-01

    The Intercomparison Studies Program (ISP) at the Oak Ridge National Laboratory (ORNL, Oak Ridge, TN USA) provides natural-matrix human urine quality-assurance/quality-control (QA/QC) samples to radiobioassay analysis laboratories. Samples are provided to these laboratories as 'single-blind' or 'double-blind' unknowns, spiked with radioactive-solution standards at 'low' levels (e.g., 0.7-7 Bq g{sup -1} for {sup 3}H and 0.7-7 Bq kg{sup -1} for {sup 90}Sr). Participants use the results as a tool for self-evaluation and a measure of performance. In this paper, sample preparation and the results of testing during the years 2001-2005 for {sup 3}H and {sup 90}Sr are presented and discussed.

  5. Morning Exercise

    ERIC Educational Resources Information Center

    Schmitt, Natalie Crohn

    2006-01-01

    In this article, Natalie Schmitt recalls her teaching experiences with morning exercise programs, beginning with her first teaching job as assistant Morning Exercise teacher at the Francis W. Parker School in Chicago. In the Morning Exercises, students were encouraged to employ all means of expression: speaking, drawing, dancing, singing, acting.…

  6. Airborne intercomparison of nitric oxide measurement techniques

    NASA Technical Reports Server (NTRS)

    Hoell, James M., Jr.; Gregory, Gerald L.; Mcdougal, David S.; Torres, Arnold L.; Davis, Douglas D.

    1987-01-01

    Results from an airborne intercomparison of techniques to measure tropospheric levels of nitric oxide (NO) are discussed. The intercomparison was part of the National Aeronautics and Space Administration's Global Tropospheric Experiment and was conducted during missions flown in the fall of 1983 and spring of 1984. Instruments intercompared included a laser-induced fluorescence (LIF) system and two chemiluminescence instruments (CL). NO mixing ratios from below 5 pptv (parts per trillion by volume) to greater than 100 pptv were reported, with the majority less than 20 pptv. Good correlation was observed between the measurements reported by the CL and LIF techniques. The general level of agreement observed for the ensemble of measurements obtained during the two missions provides the basis from which one can conclude that equally 'valid' measurements of background levels of NO can be expected from either CL or LIF instruments. At the same time the periods of disagreement that were observed between the CL and LIF instruments as well as between the two CL instruments highlight the difficulty of obtaining reliable measurements with NO mixing ratios in the 5-20 pptv range and emphasize the vigilance that should be maintained in future NO measurements.

  7. Intercomparison of ozone measurements over Antarctica

    SciTech Connect

    Margitan, J.J.; Farmer, C.B.; Toon, G.C. ); Brothers, G.A. ); Browell, E.V.; Gregory, G.L.; Hypes, W.; Larsen, J.C.; McCormick, M.P. ); Cariolle, D. ); Coffey, M.T.; Mankin, W. ); Farman, J.C. ); Harder, J.W.; Mount, G.H.; Ravishankara, A.R.; Schemeltekopf, A.L.; Tuck, A.F. ); Hofmann, D.J. ); Ismail, S.; Kooi, S. ); Jakoubek, R.O.; Proffitt, M.H.; Wahner, A.; Watterson, I. Univ. of Colorado, Boulder ); Komhyr, W. (NOAA Air Resources La

    1989-11-30

    Measurements of the abundances of ozone over Antarctic in August and September 1987 obtained during the Airborne Antarctic Ozone Experiment are intercompared. These measurements of ozone concentrations and total column abundance were obtained by three satellite instruments, two IR and one UV column-measuring instruments aboard the DC-8, one in situ DC-8, and two in situ ER-2 instruments, an upward looking lidar aboard the DC-8, and ozonesondes from four sites in Antarctica. Given the natural variability of ozone in the Antarctic and the fact that the data were not truly coincident spatially and temporally, this intercomparison is suitable only for identifying gross disparities among the techniques, rather than confirming the accuracies as rigorously as is normally done in an intercomparison. This paper presents a summary of the ozone data, using the data and accuracies given by the individual investigators in the individual papers in this issue, without any attempt to critically review or evaluate the data. In general, very good agreement (within about 10-20%, limited by natural variability) among the various techniques was found, with no systematic biases detected. These observations confirm the low ozone amounts reported in the Antarctic stratosphere.

  8. The CEOS/WGCV LPV strategy for defining FAPAR inter-comparison and validation protocols

    NASA Astrophysics Data System (ADS)

    Gobron, N.; Sanchez-Azofeifa, A.; Widlowski, J.; Pickett Heaps, C.; Meroni, M.; Plummer, S.

    2012-12-01

    The Fraction of Absorbed Photosynthetically Active Radiation (FAPAR) has been recognized as one of the fundamental terrestrial state variables in the context of global change science [Steering Committee for GCOS, 2003]. It is a key quantity in models assessing vegetation primary productivity and, more generally, in carbon cycle models implementing up-to-date land surface processes schemes. For over a decade, several FAPAR products have been derived from various space-borne optical sensors using different algorithms. Even though the quality requirements of satellite derived FAPAR products are well defined and some inter-comparisons and validation exercises have been made by individual teams, none have involved the entire community. At the same time, there is no comprehensive database of ground-based measurements of FAPAR. Such a database would address problems such as assembling the needed vertical and horizontal fluxes separately for the direct and diffuse radiation, measured with the appropriate sampling step and at a spatial resolution compatible with the remote sensing products, for the same ambient conditions as those prevailing during the acquisition of the remote sensing data. The CEOS Working Group on Calibration and Validation (WGCV) Land Product Validation (LPV) FAPAR sub-group hereby presents a strategy for defining and implementing a global inter-comparison and validation protocol for the FAPAR variable. This paper will consider various ways to perform the inter-comparisons, as well as to propose protocols for the verification of algorithms using synthetic data sets and for the validation of the products against ground-based measurements (Fluxnet, Belmanip2, NEON, TROPI-DRY and TERN).

  9. Four absolute cavity radiometer (pyrheliometer) intercomparisons at New River, Arizona: radiometer standards

    SciTech Connect

    Estey, R.S.; Seaman, C.H.

    1981-07-01

    Four detailed intercomparisons were made for a number of models of cavity-type self-calibrating radiometers (pyrheliometers). Each intercomparison consisted of simultaneous readings of pyrheliometers at 30-second intervals in runs of 10 minutes, with at least 15 runs per intercomparison. Twenty-seven instruments were in at least one intercomparison, and five were in all four. Summarized results and all raw data are provided from the intercomparisons.

  10. Intercomparison of hydrologic processes in global climate models

    NASA Technical Reports Server (NTRS)

    Lau, W. K.-M.; Sud, Y. C.; Kim, J.-H.

    1995-01-01

    In this report, we address the intercomparison of precipitation (P), evaporation (E), and surface hydrologic forcing (P-E) for 23 Atmospheric Model Intercomparison Project (AMIP) general circulation models (GCM's) including relevant observations, over a variety of spatial and temporal scales. The intercomparison includes global and hemispheric means, latitudinal profiles, selected area means for the tropics and extratropics, ocean and land, respectively. In addition, we have computed anomaly pattern correlations among models and observations for different seasons, harmonic analysis for annual and semiannual cycles, and rain-rate frequency distribution. We also compare the joint influence of temperature and precipitation on local climate using the Koeppen climate classification scheme.

  11. Intercomparison of measurements of stratospheric hydrogen fluoride

    NASA Technical Reports Server (NTRS)

    Mankin, William G.; Coffey, M. T.; Chance, K. V.; Traub, W. A.; Carli, B.; Mencaraglia, F.; Piccioli, S.; Farmer, C. B.; Seals, R. K.

    1990-01-01

    Observations of the vertical profile of hydrogen fluoride (HF) vapor in the stratosphere and of the vertical column amounts of HF above certain altitudes were made using a variety of spectroscopic instruments in the 1982 and 1983 Balloon Intercomparison Campaigns. Both emission instruments working in the far-infrared spectral region and absorption instruments using solar occultation in the 2.5-micron region were employed. No systematic differences were seen in results from the two spectral regions. A mean profile from 20 - 45 km is presented, with uncertainties ranging from 20 to 50 percent. Total columns measured from ground and from 12 km are consistent with the profile if the mixing ratio for HF is small in the troposphere and low stratosphere.

  12. Czech results at criticality dosimetry intercomparison 2002.

    PubMed

    Frantisek, Spurný; Jaroslav, Trousil

    2004-01-01

    Two criticality dosimetry systems were tested by Czech participants during the intercomparison held in Valduc, France, June 2002. The first consisted of the thermoluminescent detectors (TLDs) (Al-P glasses) and Si-diodes as passive neutron dosemeters. Second, it was studied to what extent the individual dosemeters used in the Czech routine personal dosimetry service can give a reliable estimation of criticality accident exposure. It was found that the first system furnishes quite reliable estimation of accidental doses. For routine individual dosimetry system, no important problems were encountered in the case of photon dosemeters (TLDs, film badge). For etched track detectors in contact with the 232Th or 235U-Al alloy, the track density saturation for the spark counting method limits the upper dose at approximately 1 Gy for neutrons with the energy >1 MeV. PMID:15353690

  13. The SPARC Intercomparison of Middle Atmosphere Climatologies

    NASA Technical Reports Server (NTRS)

    Randel, William; Fleming, Eric; Geller, Marvin; Gelman, Mel; Hamilton, Kevin; Karoly, David; Ortland, Dave; Pawson, Steve; Swinbank, Richard; Udelhofen, Petra

    2003-01-01

    Our current confidence in 'observed' climatological winds and temperatures in the middle atmosphere (over altitudes approx. 10-80 km) is assessed by detailed intercomparisons of contemporary and historic data sets. These data sets include global meteorological analyses and assimilations, climatologies derived from research satellite measurements, and historical reference atmosphere circulation statistics. We also include comparisons with historical rocketsonde wind and temperature data, and with more recent lidar temperature measurements. The comparisons focus on a few basic circulation statistics, such as temperature, zonal wind, and eddy flux statistics. Special attention is focused on tropical winds and temperatures, where large differences exist among separate analyses. Assimilated data sets provide the most realistic tropical variability, but substantial differences exist among current schemes.

  14. Inter-comparison of automatic rain gauges

    NASA Technical Reports Server (NTRS)

    Nystuen, Jeffrey A.

    1994-01-01

    The Ocean Acoustics Division (OAD) of the Atlantic Oceanographic and Meteorological Laboratory (AOML), in cooperation with NOAA/NESDIS and NASA, has deployed six rain gauges for calibration and intercomparison purposes. These instruments include: (1) a weighing rain gauge, (2) a RM Young Model 50202 capacitance rain gauge, (3) a ScTI ORG-705 (long path) optical rain gauge, (4) a ScTI ORG-105 (mini-ORG) optical rain gauge, (5) a Belfort Model 382 tipping bucket rain gauge, and (6) a Distromet RD-69 disdrometer. The system has been running continuously since July 1993. During this time period, roughly 150 events with maximum rainfall rate over 10 mm/hr and 25 events with maximum rainfall rates over 100 mm/hr have been recorded. All rain gauge types have performed well, with intercorrelations 0.9 or higher. However, limitations for each type of rain gauge have been observed.

  15. Ozone measurements from the Balloon Intercomparison Campaign

    NASA Astrophysics Data System (ADS)

    Robbins, D.; Waters, J.; Zimmermann, P.; Jarnot, R.; Hardy, J.; Pickett, H.; Pollitt, S.; Traub, W.; Chance, K.; Louisnard, N.; Evans, W.; Kerr, J.

    1990-02-01

    Measurements of the Balloon Intercomparison Campaign (BIC), conducted during fall, 1982 (BIC-1) and summer, 1983 (BIC-2), are reported. Results of five remote and two in situ techniques agree (with a few exceptions) within 95-percent confidence level uncertainties and generally within 15 percent above 20 km. Weighted mean profiles, which best represent conditions during the campaign, are used as a comparison standard. Accuracies of experiments indicated by BIC generally confirm estimated uncertainties for ECC sondes, UV photometry, and microwave emission experiments, are somewhat better for far-IR emission and IR absorption experiments, and are somewhat worse for IR emission and solar UV absorption experiments. The large collection of BIC measurements confirms a problem reported earlier with current theoretical modeling of ozone near 40 km.

  16. The Pliocene Model Intercomparison Project - Phase 2

    NASA Astrophysics Data System (ADS)

    Haywood, Alan; Dowsett, Harry; Dolan, Aisling; Rowley, David; Abe-Ouchi, Ayako; Otto-Bliesner, Bette; Chandler, Mark; Hunter, Stephen; Lunt, Daniel; Pound, Matthew; Salzmann, Ulrich

    2016-04-01

    The Pliocene Model Intercomparison Project (PlioMIP) is a co-ordinated international climate modelling initiative to study and understand climate and environments of the Late Pliocene, and their potential relevance in the context of future climate change. PlioMIP examines the consistency of model predictions in simulating Pliocene climate, and their ability to reproduce climate signals preserved by geological climate archives. Here we provide a description of the aim and objectives of the next phase of the model intercomparison project (PlioMIP Phase 2), and we present the experimental design and boundary conditions that will be utilised for climate model experiments in Phase 2. Following on from PlioMIP Phase 1, Phase 2 will continue to be a mechanism for sampling structural uncertainty within climate models. However, Phase 1 demonstrated the requirement to better understand boundary condition uncertainties as well as uncertainty in the methodologies used for data-model comparison. Therefore, our strategy for Phase 2 is to utilise state-of-the-art boundary conditions that have emerged over the last 5 years. These include a new palaeogeographic reconstruction, detailing ocean bathymetry and land/ice surface topography. The ice surface topography is built upon the lessons learned from offline ice sheet modelling studies. Land surface cover has been enhanced by recent additions of Pliocene soils and lakes. Atmospheric reconstructions of palaeo-CO2 are emerging on orbital timescales and these are also incorporated into PlioMIP Phase 2. New records of surface and sea surface temperature change are being produced that will be more temporally consistent with the boundary conditions and forcings used within models. Finally we have designed a suite of prioritized experiments that tackle issues surrounding the basic understanding of the Pliocene and its relevance in the context of future climate change in a discrete way.

  17. PROCORAD's international intercomparisons highlight the evolution of techniques used to determine uranium in urine.

    PubMed

    Berard, P; Montegue, A; Briot, F; Harduin, J C

    2003-01-01

    Inter-laboratory tests are a means of assessing the analytical coherence of medical laboratories. In radiotoxicology, this kind of exercise makes it possible to keep up with laboratory know-how and with the evolution and relative performances of analytical techniques. The intercomparison exercises organised by PROCORAD (Association for the Promotion of Quality Controls in Radiotoxicological Bioassays) provide an opportunity to compare and contrast radiochemistry and metrology for the in vitro analysis of urine and faeces. For uranium compounds, the development of new techniques such as inductively coupled plasma-mass spectrometry (ICP-MS), alpha spectrometry, and laser spectrofluorimetry makes it possible to compare the effectiveness of these protocols with respect to radiation protection monitoring, both in routine and special situations. Detection limits, flexibility, repeatability, reproducibility and isotopic quantification are the criteria considered in this study. The authors present the evolution of performances for the analysis of uranium in urine over the years. However, the goal of the laboratories taking part in these annual exercises is not only to check the accuracy of their results but also to have analytical discussions and the opportunity to exchange experiences that will enrich the group's general competence. PMID:14527006

  18. Intercomparison of UV/visible spectrometers for measurements of stratospheric NO2 for the Network for the Detection of Stratospheric Change

    NASA Astrophysics Data System (ADS)

    Hofmann, David; Bonasoni, Paolo; de Maziere, Martine; Evangelisti, Franco; Giovanelli, Giorgio; Goldman, Aaron; Goutail, Florence; Harder, Jerald; Jakoubek, Roger; Johnston, Paul; Kerr, Jim; Matthews, W. Andrew; McElroy, Tom; McKenzie, Richard; Mount, George; Platt, Ulrich; Pommereau, Jean-Pierre; Sarkissian, Alain; Simon, Paul; Solomon, Susan; Stutz, Jochen; Thomas, Alan; van Roozendael, Michel; Wu, Edmund

    1995-08-01

    During the period May 12-23, 1992, seven groups from seven countries met in Lauder, New Zealand, to intercompare their remote sensing instruments for the measurement of atmospheric column NO2 from the surface. The purpose of the intercomparison was to determine the degree of intercomparability and to qualify instruments for use in the Network for the Detection of Stratospheric Change (NDSC). Three of the instruments which took part in the intercomparison are slated for deployment at primary NDSC sites. All instruments were successful in obtaining slant column NO2 amounts at sunrise and sunset on most of the 12 days of the intercomparison. The group as a whole was able to make measurements of the 90° solar zenith angle slant path NO2 column amount that agreed to about ±10% most of the time; however, the sensitivity of the individual measurements varied considerably. Part of the sensitivity problem for these measurements is the result of instrumentation, and part is related to the data analysis algorithms used. All groups learned a great deal from the intercomparison and improved their results considerably as a result of this exercise.

  19. U.S. bioassay Intercomparison Studies Program at Oak Ridge National Lab

    SciTech Connect

    Payne, G.F.; Bores, N.; Melton, K.K.; Rankin, J.M.

    1998-06-01

    The Intercomparison Studies Program (ISP) for in-vitro bioassay at Oak Ridge National Laboratory (ORNL) has been in place since May 1991. The ISP was originally created to fill a need in the Radiobioassay area at ORNL, specifically in the areas of Quality Control, Quality Assurance, and Performance Testing. In the beginning, this consisted of two or three laboratories working in a pilot intercomparison program. Once it was determined that this could work effectively, the program began to seek additional members to broaden the scope of the effort. The program became formalized with a quarterly report in January 1992. The ISP currently provides cross-check blind/double-blind samples spiked with known amounts of radioactivity to various Department of Energy (DOE) facilities, universities, and private industry organizations throughout the US. These samples can be packaged according to ORNL procedures (ORNL sample bottles, ORNL chain-of-custody forms, tamper seals etc.), for a single blind sample or according to the needs of a particular facility if the double-blind sample mode is to be maintained. In 1998, the customer base was broadened to include European facilities. In January 1993, the whole-body count program was added. This involves each participating facility receiving a block phantom from the ISP and determining a geometry factor using a known standard. At quarterly intervals, each participant receives an unknown sample for analysis. The sample is counted and the data is collected for publication in an annual report. In October 1994, the fecal program was added. This involves spiking an artificial matrix with known amounts of radioactivity. Laboratories receive unknown samples on a quarterly basis. The sample is counted and the data is collected and published in a quarterly report. The ISP maintains archive samples which can be analyzed in the QC laboratory at the request of any participants if a conflict or discrepancy in a sample analysis/result occurs.

  20. The Pliocene Model Intercomparison Project - Phase 2

    NASA Astrophysics Data System (ADS)

    Haywood, Alan; Dowsett, Harry; Dolan, Aisling; Rowley, David; Abe-Ouchi, Ayako; Otto-Bliesner, Bette; Chandler, Mark; Lunt, Daniel; Salzmann, Ulrich

    2015-04-01

    The Pliocene Model Intercomparison Project (PlioMIP) is a coordinated international climate modelling initiative designed to understand climate and environments of the Late Pliocene, and their potential relevance in the context of future climate change. PlioMIP operates under the umbrella of the Palaeoclimate Modelling Intercomparison Project (PMIP), which examines multiple intervals in Earth history, the consistency of model predictions in simulating these intervals and their ability to reproduce climate signals preserved in geological climate archives. PlioMIP was initiated in 2008 and is closely aligned with the U.S. Geological Survey project known as PRISM (Pliocene Research Interpretation and Synoptic Mapping). PRISM has spent more than 25 years reconstructing and understanding mid-Pliocene climate (~3.3 to 3 million years ago), as well producing boundary condition data sets suitable for use with numerical climate models. The first phase of the PlioMIP (PlioMIP1: 2008-2014) resulted in the most complete analysis to date of the Pliocene climate. This included examination of large-scale features of global climate, detailed analyses of Pliocene ocean circulation and monsoon behaviour, and the ability of models to reproduce regional climate patterns reconstructed from both marine and terrestrial archives. The lessons learned from PlioMIP1 facilitated a revision of data and modelling approaches towards the understanding of the mid Pliocene. PlioMIP2 has now been launched, and includes significant improvements to many of the Pliocene palaeogeograhic boundary conditions used for driving climate models (new land/sea mask, topography, bathymetry and ice sheet reconstructions). Within Phase 2 modelling groups have the option of using dynamic global vegetation models to predict (rather than prescribe) land cover, and a broader portfolio of model experiments has been proposed to support efforts to better understand the Pliocene, as well as to use the Pliocene as a means

  1. Radioactive Wastes.

    PubMed

    Choudri, B S; Baawain, Mahad

    2015-10-01

    Papers reviewed herein present a general overview of radioactive waste activities around the world in 2014. These include safety assessments, decommission and decontamination of nuclear facilities, fusion facilities, transportation and management solutions for the final disposal of low and high level radioactive wastes (LLW and HLW), interim storage and final disposal options for spent fuel (SF), and tritiated wastes, with a focus on environmental impacts due to the mobility of radionuclides in water, soil and ecosystem alongwith other progress made in the management of radioactive wastes. PMID:26420096

  2. Radioactive Wastes.

    PubMed

    Choudri, B S; Baawain, Mahad

    2016-10-01

    Papers reviewed herein present a general overview of radioactive waste activities around the world in 2015. These include safety assessments, decommission and decontamination of nuclear facilities, fusion facilities, transportation and management solutions for the final disposal of low and high level radioactive wastes (LLW and HLW), interim storage and final disposal options for spent fuel (SF), and tritiated wastes, with a focus on environmental impacts due to the mobility of radionuclides in water, soil and ecosystem alongwith other progress made in the management of radioactive wastes. PMID:27620100

  3. Intercomparison of aerosol instruments: number concentration

    SciTech Connect

    Knutson, E O; Sinclair, D; Tu, K W; Hinchliffe, L; Franklin, H

    1982-05-01

    An intercomparison of aerosol instruments conducted February 23-27, 1981, at the Environmental Measurements Laboratory (EML) focused on five instruments: the Pollak and TSI condensation nucleus counters; the Active Scattering Aerosol Spectrometer (ASAS-X); and two aerosol electrometers. Test aerosols of sodium chloride and ammonium fluorescein generated by nebulization/electrostatic classification were used to obtain 195 lines of comparison data. Concentrations measured by the ASAS-X and the TSI aerosol electrometer averaged respectively 1.388 and 1.581 times that measured by the Pollak. These ratios were very stable during the week and there was little effect of particle size or material. Most other comparisons were equally stable. However, a review of past work at EML and elsewhere led to the disturbing conclusion that these ratios may change from year to year, or from season to season. A filter sample was taken from microscopy, concurrent with readings from the ASAS-X and the TSI condensation nucleus counters. In this sample, the two instruments differed by 20%. Within its 20% uncertainty, the filter result matched both the TSI and ASAS-X readings.

  4. Atmospheric model intercomparison project: Monsoon simulations

    SciTech Connect

    Sperber, K.R.; Palmer, T.N.

    1994-06-01

    The simulation of monsoons, in particular the Indian summer monsoon, has proven to be a critical test of a general circulation model`s ability to simulate tropical climate and variability. The Monsoon Numerical Experimentation Group has begun to address questions regarding the predictability of monsoon extremes, in particular conditions associated with El Nino and La Nina conditions that tend to be associated with drought and flood conditions over the Indian subcontinent, through a series of seasonal integrations using analyzed initial conditions from successive days in 1987 and 1988. In this paper the authors present an analysis of simulations associated with the Atmospheric Model Intercomparison Project (AMIP), a coordinated effort to simulate the 1979--1988 decade using standardized boundary conditions with approximately 30 atmospheric general circulation models. The 13 models analyzed to date are listed. Using monthly mean data from these simulations they have calculated indices of precipitation and wind shear in an effort to access the performance of the models over the course of the AMIP decade.

  5. International Atomic Energy Agency intercomparison of ion beam analysis software

    NASA Astrophysics Data System (ADS)

    Barradas, N. P.; Arstila, K.; Battistig, G.; Bianconi, M.; Dytlewski, N.; Jeynes, C.; Kótai, E.; Lulli, G.; Mayer, M.; Rauhala, E.; Szilágyi, E.; Thompson, M.

    2007-09-01

    Ion beam analysis (IBA) includes a group of techniques for the determination of elemental concentration depth profiles of thin film materials. Often the final results rely on simulations, fits and calculations, made by dedicated codes written for specific techniques. Here we evaluate numerical codes dedicated to the analysis of Rutherford backscattering spectrometry, non-Rutherford elastic backscattering spectrometry, elastic recoil detection analysis and non-resonant nuclear reaction analysis data. Several software packages have been presented and made available to the community. New codes regularly appear, and old codes continue to be used and occasionally updated and expanded. However, those codes have to date not been validated, or even compared to each other. Consequently, IBA practitioners use codes whose validity, correctness and accuracy have never been validated beyond the authors' efforts. In this work, we present the results of an IBA software intercomparison exercise, where seven different packages participated. These were DEPTH, GISA, DataFurnace (NDF), RBX, RUMP, SIMNRA (all analytical codes) and MCERD (a Monte Carlo code). In a first step, a series of simulations were defined, testing different capabilities of the codes, for fixed conditions. In a second step, a set of real experimental data were analysed. The main conclusion is that the codes perform well within the limits of their design, and that the largest differences in the results obtained are due to differences in the fundamental databases used (stopping power and scattering cross section). In particular, spectra can be calculated including Rutherford cross sections with screening, energy resolution convolutions including energy straggling, and pileup effects, with agreement between the codes available at the 0.1% level. This same agreement is also available for the non-RBS techniques. This agreement is not limited to calculation of spectra from particular structures with predetermined

  6. RESULTS FROM THE NORTH AMERICAN MERCURY MODEL INTER-COMPARISON STUDY (NAMMIS)

    EPA Science Inventory

    A North American Mercury Model Intercomparison Study (NAMMIS) has been conducted to build upon the findings from previous mercury model intercomparison in Europe. In the absence of mercury measurement networks sufficient for model evaluation, model developers continue to rely on...

  7. Radioactivity Calculations

    ERIC Educational Resources Information Center

    Onega, Ronald J.

    1969-01-01

    Three problems in radioactive buildup and decay are presented and solved. Matrix algebra is used to solve the second problem. The third problem deals with flux depression and is solved by the use of differential equations. (LC)

  8. Simulated Radioactivity

    ERIC Educational Resources Information Center

    Boettler, James L.

    1972-01-01

    Describes the errors in the sugar-cube experiment related to radioactivity as described in Project Physics course. The discussion considers some of the steps overlooked in the experiment and generalizes the theory beyond the sugar-cube stage. (PS)

  9. Concentrating Radioactivity

    ERIC Educational Resources Information Center

    Herrmann, Richard A.

    1974-01-01

    By concentrating radioactivity contained on luminous dials, a teacher can make a high reading source for classroom experiments on radiation. The preparation of the source and its uses are described. (DT)

  10. Healthy Exercise

    PubMed Central

    Oberman, Albert

    1984-01-01

    Persons at any age can substantially improve their fitness for work and play through appropriate exercise training. Considerable evidence indicates that physical activity is valuable for weight control, modifying lipids and improving carbohydrate tolerance. Less rigorous scientific data are available for associated long-term blood pressure and psychological changes with habitual exercise. Strenuous physical activity most likely reduces the incidence of coronary heart disease and the detrimental impact of certain chronic diseases on health. Adverse effects may result from a training program, but the major concern is the susceptibility to cardiovascular events during and immediately after exertion. To achieve optimal benefits with minimal risk, exercise must be carefully prescribed within the context of overall health and training objectives. Taken altogether, a distinct rationale exists for regular vigorous exercise as an integral part of a personal health maintenance program. PMID:6395501

  11. Exercise Habit

    MedlinePlus

    ... lungs. Examples of aerobic exercise include walking, hiking, running, aerobic dance, biking, rowing, swimming, and cross-country ... Brisk walking can burn as many calories as running, but it is less likely to cause injuries ...

  12. Compulsive Exercise

    MedlinePlus

    ... diseases. Many teens who play sports have higher self-esteem than their less active pals, and exercise can ... may have a distorted body image and low self-esteem. They may see themselves as overweight or out ...

  13. Exercise response

    NASA Technical Reports Server (NTRS)

    Rummel, J. A.; Sawin, C. F.; Michel, E. L.

    1975-01-01

    The bicycle ergometer and a graded stress protocol were used to conduct exercise stress tests for the Apollo project. The graded exercise tests permitted a progressive evaluation of physiological control system response and provided a better understanding of safe stress limits; heart rate was used for determining stress levels. During each test, workload, heart rate, blood pressure, and respiratory gas exchange (oxygen consumption, carbon dioxide production, and minute volume) measurements were made. The results are presented and discussed.

  14. Intercomparison of Hydrologic Processes in AMIP GCMs.

    NASA Astrophysics Data System (ADS)

    Lau, K.-M.; Sud, Y.; Kim, J. H.

    1996-10-01

    Results of an intercomparison study under the Atmospheric Model Intercomparison Project (AMIP) to assess the abilities of 29 global climate models (GCMS) in simulating various aspects of regional and hydrologic processes in response to observed sea surface temperature and sea ice boundary forcings are presented. The authors find that the models generally portray an earthlike climate to approximately 10%-20% of the global land surface temperature (=14.8°C) and global precipitation (=2.3 mm day1). While a majority of the models have a reasonable global water budget, about a quarter of the models show significant errors in the total global water balance.While the model frequency distributions of heavy precipitation associated with deep convection are in reasonable agreement with observations, a systematic underestimate of the frequency of occurrence of light precipitation events (< 1 mm day1) is present in almost all the AMIP models, especially over continental desert regions and over tropical and subtropical oceanic regions contiguous to the west coasts of continents where low-level stratocumulus clouds tend to occur. This discrepancy is presumably related to the crude treatment of moist processes, especially those related to low clouds and nonconvective precipitation in the models. Another common problem in the global rainfall distribution is the presence of spectral rain or spurious gridpoint-scale heavy rain. The artificial anchoring of rainfall to topographic features in the Maritime Continent appears to be a generic problem in many GCMs. Models differ substantially in the magnitude of the rainfall amount over the eastern Pacific ITCZ for all seasons. The simulated boreal summer rainfall distributions have large variability over the Indian subcontinent and the Bay of Bengal. The northward migration of the monsoon convective zones are not well simulated. In particular, the Fast Asian monsoon rainband over the subtropical western Pacific is ill-defined or absent

  15. Tenth ORNL Personnel Dosimetry Intercomparison Study

    SciTech Connect

    Swaja, R.E.; Chou, T.L.; Sims, C.S.; Greene, R.T.

    1985-03-01

    The Tenth Personnel Dosimetry Intercomparison Study was conducted at the Oak Ridge National Laboratory during April 9-11, 1984. Dosemeter badges from 31 participating organizations were mounted on 40cm Lucite phantoms and exposed to a range of dose equivalents which could be encountered during routine personnel monitoring in mixed radiation fields. The Health Physics Research Reactor served as the only source of radiation for eight of the ten irradiations which included a low (approx. 0.50 mSv) and high (approx. 10.00 mSv) neutron dose equivalent run for each of four shield conditions. Two irradiations were also conducted for which concrete- and Lucite-shield reactor irradiations were gamma-enhanced using a /sup 137/Cs source. Results indicated that some participants had difficulty obtaining measurable indication of neutron and gamma exposures at dose equivalents less than about 0.50 mSv and 0.20 mSv, respectively. Albedo dosemeters provided the best overall accuracy and precision for the neutron measurements. Direct interaction TLD systems showed significant variation in accuracy with incident spectrum, and threshold neutron dosemeters (film and recoil track) underestimated reference values by more than 50%. Gamma dose equivalents estimated in the mixed fields were higher than reference values with TL gamma dosemeters generally yielding more accurate results than film. Under the conditions of this study in which participants had information concerning exposure conditions and radiation field characteristics prior to dosemeter evaluation, only slightly more than half of all reported results met regulatory standards for neutron and gamma accuracy. 19 refs., 2 figs., 29 tabs.

  16. Intercomparison Between Microwave Radiometer and Radiosonding Data

    NASA Astrophysics Data System (ADS)

    Toanca, Florica; Stefan, Sabina

    2014-05-01

    The aim of this study is to compare relative humidity and temperature vertical profiles measured by ground based Microwave Radiometer (MWR) RPG HATPRO installed at the Romanian Atmospheric Observatory (Magurele, 44.35 N, 26.03 E) and by radio-sounding (RS) (Baneasa, 44.30 N, 26.04 E) provided by National Meteorological Administration. MWR uses passive microwave detection in the 22.335 to 31.4 GHz and 51to 58 GHz bands to obtain the vertical profiles of temperature and relative humidity up to 10km with a temporal resolution of several minutes. The reliability of atmospheric temperature and relative humidity profiles retrieved continuously by the MWR for the winter and summer of year 2013 was studied. The study was conducted, comparing the temperature and humidity profiles from the MWR with the ones from the radio soundings at 0:00 a.m. Two datasets of the humidity show a fairly good agreement for the interval between ground and 1.5 km in the January month for winter and up to 2 km in the July month for summer. Above 2 km, for the both seasons, the humidity profiles present in most of the selected cases the same trend evolution. The temperature vertical profiles agreed in 95% of the cases during summer and 85% during winter. It is very important for intercomparison that for both seasons almost all temperature vertical profiles highlight temperature inversions. Two cases have been analyzed in order to find possible explanations for the discrepancies between vertical profiles, focusing on advantages and disadvantages of MWR measurements.

  17. Intercomparison of statistical and dynamical downscaling models under the EURO- and MED-CORDEX initiative framework: present climate evaluations

    NASA Astrophysics Data System (ADS)

    Vaittinada Ayar, Pradeebane; Vrac, Mathieu; Bastin, Sophie; Carreau, Julie; Déqué, Michel; Gallardo, Clemente

    2016-02-01

    Given the coarse spatial resolution of General Circulation Models, finer scale projections of variables affected by local-scale processes such as precipitation are often needed to drive impacts models, for example in hydrology or ecology among other fields. This need for high-resolution data leads to apply projection techniques called downscaling. Downscaling can be performed according to two approaches: dynamical and statistical models. The latter approach is constituted by various statistical families conceptually different. If several studies have made some intercomparisons of existing downscaling models, none of them included all those families and approaches in a manner that all the models are equally considered. To this end, the present study conducts an intercomparison exercise under the EURO- and MED-CORDEX initiative hindcast framework. Six Statistical Downscaling Models (SDMs) and five Regional Climate Models (RCMs) are compared in terms of precipitation outputs. The downscaled simulations are driven by the ERAinterim reanalyses over the 1989-2008 period over a common area at 0.44° of resolution. The 11 models are evaluated according to four aspects of the precipitation: occurrence, intensity, as well as spatial and temporal properties. For each aspect, one or several indicators are computed to discriminate the models. The results indicate that marginal properties of rain occurrence and intensity are better modelled by stochastic and resampling-based SDMs, while spatial and temporal variability are better modelled by RCMs and resampling-based SDM. These general conclusions have to be considered with caution because they rely on the chosen indicators and could change when considering other specific criteria. The indicators suit specific purpose and therefore the model evaluation results depend on the end-users point of view and how they intend to use with model outputs. Nevertheless, building on previous intercomparison exercises, this study provides a

  18. ARM/GCSS/SPARC TWP-ICE CRM Intercomparison Study

    NASA Technical Reports Server (NTRS)

    Fridlind, Ann; Ackerman, Andrew; Petch, Jon; Field, Paul; Hill, Adrian; McFarquhar, Greg; Xie, Shaocheng; Zhang, Minghua

    2010-01-01

    Specifications are provided for running a cloud-resolving model (CRM) and submitting results in a standardized format for inclusion in a n intercomparison study and archiving for public access. The simulated case study is based on measurements obtained during the 2006 Tropical Warm Pool - International Cloud Experiment (TWP-ICE) led by the U. S. department of Energy Atmospheric Radiation Measurement (ARM) program. The modeling intercomparison study is based on objectives developed in concert with the Stratospheric Processes And their Role in Climate (SPARC) program and the GEWEX cloud system study (GCSS) program. The Global Energy and Water Cycle Experiment (GEWEX) is a core project of the World Climate Research PRogramme (WCRP).

  19. QUADOS intercomparison: a summary of photon and charged particle problems.

    PubMed

    Gualdrini, G; Agosteo, S; Ménard, S; Price, R A; Chartier, J-L; Grosswendt, B; Kodeli, I; Leuthold, G P; Siebert, B R L; Tagziria, H; Tanner, R J; Terrissol, M; Zankl, M

    2005-01-01

    QUADOS, a Concerted Action of the European Commission, has promoted an intercomparison aimed at evaluating the use of computational codes for dosimetry in radiation protection and medical physics. This intercomparison was open to all users of radiation transport codes. Eight problems were selected for their relevance to the radiation dosimetry community, five of which involved photon and proton transport. This paper focuses on the analysis of the photon and charged particle problems. The neutron problems were presented in a paper at the NEUDOS9 conference. PMID:16381790

  20. Contribution towards statistical intercomparison of general circulation models

    SciTech Connect

    Sengupta, S.; Boyle, J.

    1995-06-01

    The Atmospheric Model Intercomparison Project (AMIP) of the World Climate Research Programme`s Working Group on Numerical Experimentation (WGNE) is an ambitious attempt to comprehensively intercompare atmospheric General Circulation Models (GCMs). The participants in AMIP simulate the global atmosphere for the decade 1979 to 1988 using, a common solar constant and Carbon Dioxide(CO{sub 2}) concentration and a common monthly averaged sea surface temperature (SST) and sea ice data set. In this work we attempt to present a statistical framework to address the difficult task of model intercomparison and verification.

  1. Intercomparison of Global Precipitation Products: The Third Precipitation Intercomparison Project (PIP-3)

    NASA Technical Reports Server (NTRS)

    Adler, Robert F.; Kidd, Christopher; Petty, Grant; Morrissey, Mark; Goodman, H. Michael; Einaudi, Franco (Technical Monitor)

    2000-01-01

    A set of global, monthly rainfall products has been intercompared to understand the quality and utility of the estimates. The products include 25 observational (satellite-based), four model and two climatological products. The results of the intercomparison indicate a very large range (factor of two or three) of values when all products are considered. The range of values is reduced considerably when the set of observational products is limited to those considered quasi-standard. The model products do significantly poorer in the tropics, but are competitive with satellite-based fields in mid-latitudes over land. Over ocean, products are compared to frequency of precipitation from ship observations. The evaluation of the observational products point to merged data products (including rain gauge information) as providing the overall best results.

  2. The Agriculture Model Intercomparison and Improvement Project (AgMIP) (Invited)

    NASA Astrophysics Data System (ADS)

    Rosenzweig, C.

    2010-12-01

    The Agricultural Model Intercomparison and Improvement Project (AgMIP) is a distributed climate-scenario simulation exercise for historical model intercomparison and future climate change conditions with participation of multiple crop and world agricultural trade modeling groups around the world. The goals of AgMIP are to improve substantially the characterization of risk of hunger and world food security due to climate change and to enhance adaptation capacity in both developing and developed countries. Historical period results will spur model improvement and interaction among major modeling groups, while future period results will lead directly to tests of adaptation and mitigation strategies across a range of scales. AgMIP will consist of a multi-scale impact assessment utilizing the latest methods for climate and agricultural scenario generation. Scenarios and modeling protocols will be distributed on the web, and multi-model results will be collated and analyzed to ensure the widest possible coverage of agricultural crops and regions. AgMIP will place regional changes in agricultural production in a global context that reflects new trading opportunities, imbalances, and shortages in world markets resulting from climate change and other driving forces for food supply. Such projections are essential inputs from the Vulnerability, Impacts, and Adaptation (VIA) research community to the Intergovernmental Panel on Climate Change Fifth Assessment (AR5), now underway, and the UN Framework Convention on Climate Change. They will set the context for local-scale vulnerability and adaptation studies, supply test scenarios for national-scale development of trade policy instruments, provide critical information on changing supply and demand for water resources, and elucidate interactive effects of climate change and land use change. AgMIP will not only provide crucially-needed new global estimates of how climate change will affect food supply and hunger in the

  3. The Agricultural Model Intercomparison and Improvement Project (AgMIP): Progress and Preliminary Results

    NASA Astrophysics Data System (ADS)

    Rosenzweig, C.

    2011-12-01

    The Agricultural Model Intercomparison and Improvement Project (AgMIP) is a distributed climate-scenario simulation exercise for historical model intercomparison and future climate change conditions with participation of multiple crop and agricultural trade modeling groups around the world. The goals of AgMIP are to improve substantially the characterization of risk of hunger and world food security due to climate change and to enhance adaptation capacity in both developing and developed countries. Recent progress and the current status of AgMIP will be presented, highlighting three areas of activity: preliminary results from crop pilot studies, outcomes from regional workshops, and emerging scientific challenges. AgMIP crop modeling efforts are being led by pilot studies, which have been established for wheat, maize, rice, and sugarcane. These crop-specific initiatives have proven instrumental in testing and contributing to AgMIP protocols, as well as creating preliminary results for aggregation and input to agricultural trade models. Regional workshops are being held to encourage collaborations and set research activities in motion for key agricultural areas. The first of these workshops was hosted by Embrapa and UNICAMP and held in Campinas, Brazil. Outcomes from this meeting have informed crop modeling research activities within South America, AgMIP protocols, and future regional workshops. Several scientific challenges have emerged and are currently being addressed by AgMIP researchers. Areas of particular interest include geospatial weather generation, ensemble methods for climate scenarios and crop models, spatial aggregation of field-scale yields to regional and global production, and characterization of future changes in climate variability.

  4. Assessment of Remotely Sensed Land Surface Phenology Data for North America: Inter-comparison and Forecasting

    NASA Astrophysics Data System (ADS)

    Zhang, G.; Ganguly, S.; White, M. A.; Nemani, R. R.; Hiatt, S. H.; Hashimoto, H.; Milesi, C.; Wang, W.; Michaelis, A.; Votava, P.; Melton, F. S.; Dungan, J. L.

    2010-12-01

    Land surface phenology is widely used as a diagnostic of ecosystem response to global change and influences seasonal scale fluxes of water, energy, and carbon between the land surface and atmosphere. While many data sets related to plant phenology have been collected at specific sites or in networks focused on individual plants or plant species, a robust framework in classifying the ground phenological events to compare with remotely sensed phenology is lacking. In this research, we develop a methodology to compare the latest Collection 5 500m MODIS phenology data (cardinal dates corresponding to greenup, maturity, senescence and dormancy) with all available ground observed data for North America for the period 2001-2006. Inter-comparison results show that the MODIS phenology product performs well in capturing the “earliest events” corresponding to each of the phenological phases (e.g. budburst, first leaf, first leaf color change) of plant growth in a community. Of all the ground phenological stages, the leaf greenup events are best correlated to the MODIS greenup onset. Establishing confidence in the MODIS greenup onset data through our inter-comparison exercise and exploiting the long-term nature of the data set (2001-present) led us to build a seasonal phenology forecast model within the Terrestrial Observation and Prediction System (TOPS) framework. The available MODIS greenup data serves as a training data to our climate based phenology forecast model. We parameterize the empirical model for each 500m pixel based on the relationship between local climate provided by TOPS and MODIS greenup. As a test case, we have predicted the greenup for 2010 spring by using the seasonal climate forecast data from NECP Climate Forecast System (CFS) to our forecast model. The phenology forecast portal is now available online, which provides a unique platform for community participation in monitoring local phenology forecast events and uploading observed phenological

  5. RADIOACTIVE BATTERY

    DOEpatents

    Birden, J.H.; Jordan, K.C.

    1959-11-17

    A radioactive battery which includes a capsule containing the active material and a thermopile associated therewith is presented. The capsule is both a shield to stop the radiations and thereby make the battery safe to use, and an energy conventer. The intense radioactive decay taking place inside is converted to useful heat at the capsule surface. The heat is conducted to the hot thermojunctions of a thermopile. The cold junctions of the thermopile are thermally insulated from the heat source, so that a temperature difference occurs between the hot and cold junctions, causing an electrical current of a constant magnitude to flow.

  6. The Coupled Model Intercomparison Project (CMIP).

    NASA Astrophysics Data System (ADS)

    Meehl, Gerald A.; Boer, George J.; Covey, Curt; Latif, Mojib; Stouffer, Ronald J.

    2000-02-01

    The Coupled Model Intercomparison Project (CMIP) was established to study and intercompare climate simulations made with coupled ocean-atmosphere-cryosphere-land GCMs. There are two main phases (CMIP1 and CMIP2), which study, respectively, 1) the ability of models to simulate current climate, and 2) model simulations of climate change due to an idealized change in forcing (a 1% per year CO2 increase). Results from a number of CMIP projects were reported at the first CMIP Workshop held in Melbourne, Australia, in October 1998. Some recent advances in global coupled modeling related to CMIP were also reported. Presentations were based on preliminary unpublished results. Key outcomes from the workshop were that 1) many observed aspects of climate variability are simulated in global coupled models including the North Atlantic oscillation and its linkages to North Atlantic SSTs, El Niño-like events, and monsoon interannual variability; 2) the amplitude of both high- and low-frequency global mean surface temperature variability in many global coupled models is less than that observed, with the former due in part to simulated ENSO in the models being generally weaker than observed, and the latter likely to be at least partially due to the uncertainty in the estimates of past radiative forcing; 3) an El Niño-like pattern in the mean SST response with greater surface warming in the eastern equatorial Pacific than the western equatorial Pacific is found by a number of models in global warming climate change experiments, but other models have a more spatially uniform or even a La Niña-like, response; 4) flux adjustment, by definition, improves the simulation of mean present-day climate over oceans, does not guarantee a drift-free climate, but can produce a stable base state in some models to enable very long term (1000 yr and longer) integrations-in these models it does not appear to have a major effect on model processes or model responses to increasing CO2; and 5) recent

  7. Daily exercise routines

    NASA Technical Reports Server (NTRS)

    Anderson, Patrick L.; Amoroso, Michael T.

    1990-01-01

    Viewgraphs on daily exercise routines are presented. Topics covered include: daily exercise and periodic stress testings; exercise equipment; physiological monitors; exercise protocols; physiological levels; equipment control; control systems; and fuzzy logic control.

  8. Exercise and age

    MedlinePlus

    Age and exercise ... It is never too late to start exercising. Exercise has benefits at any age. Don't worry ... as you age. The right kind of regular exercise can also reduce your risk of heart disease, ...

  9. Exercise and Posture

    MedlinePlus

    ... Info For Teens Message Boards & Forums Donate Shop Exercise & Posture About Spondylitis / Exercise & Posture Overview For The ... Diet Blood Work and Spondylitis Spondylitis Awareness Month Exercise Exercise is an integral part of any spondylitis ...

  10. Exercise-Induced Bronchoconstriction

    MedlinePlus

    ... Conditions & Treatments ▸ Conditions Dictionary ▸ Exercise-Induced Bronchoconstriction Share | Exercise-Induced Bronchoconstriction (EIB) « Back to A to Z Listing Exercise-Induced Bronchoconstriction, (EIB), often known as exercise-induced ...

  11. Diabetes and exercise

    MedlinePlus

    ... medlineplus.gov/ency/patientinstructions/000083.htm Diabetes and exercise To use the sharing features on this page, ... not exercising at all. Your Blood Sugar and Exercise Check your blood sugar before you exercise. Also, ...

  12. Exercise at Home

    MedlinePlus

    ... Divisions Home Health Insights Exercise Exercise at Home Exercise at Home Make an Appointment Ask a Question ... with the movement and contact your provider. Posture Exercises Better posture means better breathing and movement. Axial ...

  13. Exercise-induced asthma

    MedlinePlus

    Wheezing - exercise-induced; Reactive airway disease - exercise ... Having asthma symptoms when you exercise does not mean you cannot or should not exercise. But be aware of your EIA triggers. Cold or dry air may ...

  14. Radioactive Waste.

    ERIC Educational Resources Information Center

    Blaylock, B. G.

    1978-01-01

    Presents a literature review of radioactive waste disposal, covering publications of 1976-77. Some of the studies included are: (1) high-level and long-lived wastes, and (2) release and burial of low-level wastes. A list of 42 references is also presented. (HM)

  15. Radioactive wastes

    SciTech Connect

    Devarakonda, M.S.; Hickox, J.A.

    1996-11-01

    This paper provides a review of literature published in 1995 on the subject of radioactive wastes. Topics covered include: national programs; waste repositories; mixed wastes; decontamination and decommissioning; remedial actions and treatment; and environmental occurrence and transport of radionuclides. 155 refs.

  16. THE NORTH AMERICAN MERCURY MODEL INTER-COMPARISON STUDY (NAMMIS)

    EPA Science Inventory

    This paper describes the North American Mercury Model Inter-comparison Study (NAMMIS). The NAMMIS is an effort to apply atmospheric Hg models in a tightly constrained testing environment with a focus on North America. With each model using the same input data sets for initial co...

  17. Evaluation of the annual Canadian biodosimetry network intercomparisons

    PubMed Central

    Wilkins, Ruth C.; Beaton-Green, Lindsay A.; Lachapelle, Sylvie; Kutzner, Barbara C.; Ferrarotto, Catherine; Chauhan, Vinita; Marro, Leonora; Livingston, Gordon K.; Boulay Greene, Hillary; Flegal, Farrah N.

    2015-01-01

    Abstract Purpose: To evaluate the importance of annual intercomparisons for maintaining the capacity and capabilities of a well-established biodosimetry network in conjunction with assessing efficient and effective analysis methods for emergency response. Materials and methods: Annual intercomparisons were conducted between laboratories in the Canadian National Biological Dosimetry Response Plan. Intercomparisons were performed over a six-year period and comprised of the shipment of 10–12 irradiated, blinded blood samples for analysis by each of the participating laboratories. Dose estimates were determined by each laboratory using the dicentric chromosome assay (conventional and QuickScan scoring) and where possible the cytokinesis block micronucleus (CBMN) assay. Dose estimates were returned to the lead laboratory for evaluation and comparison. Results: Individual laboratories performed comparably from year to year with only slight fluctuations in performance. Dose estimates using the dicentric chromosome assay were accurate about 80% of the time and the QuickScan method for scoring the dicentric chromosome assay was proven to reduce the time of analysis without having a significant effect on the dose estimates. Although analysis with the CBMN assay was comparable to QuickScan scoring with respect to speed, the accuracy of the dose estimates was greatly reduced. Conclusions: Annual intercomparisons are necessary to maintain a network of laboratories for emergency response biodosimetry as they evoke confidence in their capabilities. PMID:25670072

  18. PM 2.5 ORGANIC SPECIATION INTERCOMPARISON RESULTS

    EPA Science Inventory

    This abstract describes a poster on results to a laboratory intercomparison of organic aerosol speciation analysis to be presented at the 2006 International Aerosol Conference sponsored by the American Association for Aerosol Research in St. Paul, Minnesota on September 10-15. T...

  19. Low-cost solar array project: Four absolute cavity radiometer (pyrheliometer) intercomparisons at New River, Arizona: Radiometer standards

    NASA Technical Reports Server (NTRS)

    Estey, R. S.; Seaman, C. H.

    1981-01-01

    Four detailed intercomparisons were made for a number of models of cavity-type self-calibrating radiometers (pyrheliometers). Each intercomparison consisted of simultaneous readings of pyrheliometers at 30-second intervals in runs of 10 minutes, with at least 15 runs per intercomparison. Twenty-seven instruments were in at least one intercomparison, and five were in all four. Summarized results and all raw data are provided from the intercomparisons.

  20. Budget Exercise.

    ERIC Educational Resources Information Center

    Clowes, Darrel A.

    Following a discussion of the factors to be considered in constructing feasible college budgets, an exercise in budget development is presented involving a hypothetical community college with 2,500 full-time equivalent (FTE) students, 500 in developmental education, 750 each in transfer and technical programs, and 500 undecided. Exercise…

  1. Exercise apparatus

    NASA Technical Reports Server (NTRS)

    Schaffner, Grant (Inventor); Bentley, Jason R. (Inventor); Loehr, James A. (Inventor); Gundo, Daniel P. (Inventor)

    2006-01-01

    An apparatus and method for exercising whereby the user is supported by various mechanisms in such as way that the user's shoulder area is free to translate and rotate; the user's pelvic area is free to translate and rotate; or in any combination.

  2. Intercomparison of two comparative reactivity method instruments inf the Mediterranean basin during summer 2013

    NASA Astrophysics Data System (ADS)

    Zannoni, N.; Dusanter, S.; Gros, V.; Sarda Esteve, R.; Michoud, V.; Sinha, V.; Locoge, N.; Bonsang, B.

    2015-09-01

    The hydroxyl radical (OH) plays a key role in the atmosphere, as it initiates most of the oxidation processes of volatile organic compounds (VOCs), and can ultimately lead to the formation of ozone and secondary organic aerosols (SOAs). There are still uncertainties associated with the OH budget assessed using current models of atmospheric chemistry and direct measurements of OH sources and sinks have proved to be valuable tools to improve our understanding of the OH chemistry. The total first order loss rate of OH, or total OH reactivity, can be directly measured using three different methods, such as the following: total OH loss rate measurement, laser-induced pump and probe technique and comparative reactivity method. Observations of total OH reactivity are usually coupled to individual measurements of reactive compounds in the gas phase, which are used to calculate the OH reactivity. Studies using the three methods have highlighted that a significant fraction of OH reactivity is often not explained by individually measured reactive compounds and could be associated to unmeasured or unknown chemical species. Therefore accurate and reproducible measurements of OH reactivity are required. The comparative reactivity method (CRM) has demonstrated to be an advantageous technique with an extensive range of applications, and for this reason it has been adopted by several research groups since its development. However, this method also requires careful corrections to derive ambient OH reactivity. Herein we present an intercomparison exercise of two CRM instruments, CRM-LSCE (Laboratoire des Sciences du Climat et de l'Environnement) and CRM-MD (Mines Douai), conducted during July 2013 at the Mediterranean site of Ersa, Cape Corsica, France. The intercomparison exercise included tests to assess the corrections needed by the two instruments to process the raw data sets as well as OH reactivity observations. The observation was divided in three parts: 2 days of plant

  3. Results of the NY-Alesund ozone measurements intercomparison NAOMI

    NASA Technical Reports Server (NTRS)

    Steinbrecht, W.; Gross, M.; McGee, T.; Neuber, R.; Gathen, P. V. D.; Wahl, P.; Klein, U.; Langer, J.

    1998-01-01

    Worldwide, about ten Differential Absorption Lidars are used for long-term monitoring of stratospheric ozone. These systems are an important component of the Network for the Detection of Stratospheric Change. Although DIALs are self-calibrating in principle, regular intercomparisons with other ozone-lidars, microwave radiometers or ozone-sondes are highly desirable to ensure high data quality at a well known level. The Network for the Detection of Stratospheric Change (NDSC) validation policy suggests that such intercomparisons be "blind", meaning all participants submit their data to an impartial referee, without seeing results from the other participants. Here we report on the "blind" intercomparison taking place from January 20th to February 10th 1998 at Ny-Alesund, Spitsbergen (78.92 deg N, 11.95 deg E). Participating groups were from the Alfred Wegener Institute, Potsdam, operating the NDSC DIAL system at Ny-Alesund, from the University of Bremen operating the NDSC microwave radiometer for ozone profiling at Ny-Alesund, and the NASA Goddard Space Flight Center group with the "NDSC travelling standard" STROZ-LITE. The first author acted as the impartial referee. Also used for the intercomparison were data from ECC-6A/Vaisala RS80 ozone sondes routinely launched at Ny-Alesund by the AWI group. A 1% KI solution (3 ml) and the 1986 ECC pump correction (1.092 at 5 hPa) are used. The ECC-data were available to all participants during the campaign and thus were not "blind". Table 1 summarizes the expected performance of the instruments participating in the ozone intercomparison reported in this paper.

  4. Intercomparison of Reanalyses Dynamic Variables in the Stratosphere: Results from the SPARC-Reanalysis Intercomparison Project

    NASA Astrophysics Data System (ADS)

    Fujiwara, M.; Long, C. S.; Zhang, L.

    2014-12-01

    The Stratospheric-Tropospheric Processes and their Role in Climate (SPARC)-Reanalysis Intercomparison Project (S-RIP) is in the process of generating a multi-chapter report describing the thermal, dynamic, and chemical characteristics of the recent and past reanalyses. This presentation will focus on the basic characteristics of the thermal and dynamic variables (temperatures, heights, winds). In order to not favor any one particular reanalysis, an ensemble mean of the four most recent reanalyses [CFSR, MERRA, ERA-Interim, and the JRA55] has been created. Differences from this ensemble mean indicate how these four reanalyses and previous reanalyses differ in their long term climatology and time evolution of their dynamic variables at both poles and in the tropics. Differences from the ensemble mean indicate issues with how the analysis systems managed data poor time periods, consequences of bias correction, the transition from the SSU to AMSU observing systems, and differences in the annual amplitudes. The RMS of their differences over time indicates that there is an increase in their agreement from 1979 to present with greater agreement occurring in the AMSU time period.

  5. Orthostasis: exercise and exercise training

    NASA Technical Reports Server (NTRS)

    Geelen, G.; Greenleaf, J. E.

    1993-01-01

    There are two major problems here that are not independent. One is the more practically oriented problem of determining the effect of various modes of exercise training on gravitational tolerances, i.e., the point of syncope (unconsciousness) usually estimated from the time of appearance of presyncopal signs and symptoms. The other is more theoretical and concerns the mechanism of blood pressure failure that results in syncope. In many experimental designs these two problems or purposes have been intermingled, with equivocal results.

  6. Spectroradiometer Intercomparison and Impact on Characterizing Photovoltaic Device Performance: Preprint

    SciTech Connect

    Habte, A.; Andreas, A.; Ottoson, L.; Gueymard, C.; Fedor, G.; Fowler, S.; Peterson, J.; Naranen, E.; Kobashi, T.; Akiyama, A.; Takagi, S.

    2014-11-01

    Indoor and outdoor testing of photovoltaic (PV) device performance requires the use of solar simulators and natural solar radiation, respectively. This performance characterization requires accurate knowledge of spectral irradiance distribution that is incident on the devices. Spectroradiometers are used to measure the spectral distribution of solar simulators and solar radiation. On September 17, 2013, a global spectral irradiance intercomparison using spectroradiometers was organized by the Solar Radiation Research Laboratory (SRRL) at the National Renewable Energy Laboratory (NREL). This paper presents highlights of the results of this first intercomparison, which will help to decrease systematic inter-laboratory differences in the measurements of the outputs or efficiencies of PV devices and harmonize laboratory experimental procedures.

  7. The EWGRD Round Robin Measurement Exercise

    NASA Astrophysics Data System (ADS)

    Thornton, D. A.; Wagemans, J.; Fernandes, A. C.; Girard, J. M.; Kis, D. P.; Klupák, V.; Mutnuru, R.; Philibert, H.; Rousseau, G.; Santos, J. P.; Serén, T.; Zsolnay, E. M.

    2016-02-01

    This paper presents the results of a round robin exercise carried out to compare specific activity measurements performed by eight European organisations on a set of ten neutron activation detectors containing the radio-nuclides 110mAg, 60Co, 54Mn, 46Sc and 94Nb. The purpose of the exercise was to demonstrate the level of consistency between the participating organisations in blind tests of measurements relevant to reactor metrology. The samples used were selected from a stock of pre-existing irradiated material held at SCK•CEN. Taking turns over a period of approximately 9 months, the participating organisations received the samples, measured them and provided their results to an independent referee who collated and compared the data. The inter-comparison has demonstrated good agreement between the participants with standard deviations for each dosimeter varying between 1.6% and 3.1%. The paper provides results of the EWGRD Round Robin in an anonymised form together with discussion and conclusions which may be drawn from the exercise.

  8. Exercise and Compulsive Behavior.

    ERIC Educational Resources Information Center

    Polivy, Janet; Clendenen, Vanessa

    Although reports on the positive effects of fitness and exercise predominate in the exercise literature, some researchers describe frequent exercise as compulsive or addictive behavior. This paper addresses these "negative addictions" of exercise. As early as 1970, researchers recognized the addictive qualities of exercise. Short-term studies on…

  9. An Intercomparison of Airborne VOC and PAN Measurements

    NASA Astrophysics Data System (ADS)

    Hansel, A.; Wisthaler, A.; Flocke, F.; Weinheimer, A.; Fall, R.; Goldan, P.; Hübler, G.; Fehsenfeld, F. C.

    2002-12-01

    As part of the Texas Air Quality Study (TexAQS 2000) an informal airborne intercomparison has been conducted to evaluate the state-of-the-art of fast-response, in-situ methods for analyzing Volatile Organic Compounds (VOCs) and peroxyacetyl nitrate (PAN). Instrumentation included a Proton-Transfer-Reaction Mass Spectrometer (PTR-MS), the Tropospheric Airborne Chromatograph for Oxy-hydrocarbons and Hydrocarbons (TACOH) and a gas chromatograph for PAN detection using electron capture (GC/ECD). The measurements were made in the Greater Houston area and East Texas in August/September 2000 during 13 flights with the NSF/NCAR ELECTRA aircraft. The intercomparison was conducted mainly in the boundary layer but included some encounters with air masses from the free troposphere. Final results from the intercomparison show that measurements of acetaldehyde, isoprene, the sum\\textsuperscript{*} of acetone and propanal, the sum\\textsuperscript{*} methyl vinyl ketone and methacrolein (\\textsuperscript{*} PTR-MS does not distinguish between isobaric species) and toluene agree very well. Poor agreement was achieved in the case of methanol and the underlying sensitivity problem in the PTR-MS or TACOH system is under investigation. The results of the PAN intercomparison indicate that the PTR-MS technique suffered from an interference most likely associated with the presence of peracetic acid in photochemically aged air. If this interfering signal was traced by periodically inserting a selective PAN scrubber (thermal decomposition) into the sample air stream and subtracted from the original signal, the corrected PTR-MS PAN data are in very good agreement with the GC/ECD results.

  10. Bootstrap-based intercomparison of regional flood estimation procedures

    SciTech Connect

    Ouarda, T.B.M.J.; Ashkar, F.

    1995-12-31

    The present paper describes a methodology, based on the regional bootstrap procedure, for the intercomparison of some of the most frequently used regional flood frequency estimation models. The results of the application of this methodology, with Canadian flood data, for comparing the different regional estimation models are also presented. A regional model C{sub ij} = [DRH]{sub i} x [MER]{sub j} (i=1,...,L ; j=1,...,M) is obtained by combining a methodology for the delineation of homogeneous regions [DRH]{sub i} and a regional estimation method [MER]{sub j}. These regional models are compared with respect to their ability to provide reliable estimates of certain flood quantiles (floods with return periods of 10 and 100 years). Two types of bootstrapping have been applied within the framework of this project: the classical scalar bootstrap used in at-site estimation, and the vector (or regional) bootstrap procedure applied in the intercomparison between the different regional models. This last technique is illustrated with an example, and all the details of the procedure are presented. The performance indices that were employed for the purpose of the intercomparison are also detailed. One important feature of regional bootstrapping is that it preserves the regional dependence structure between annual flood values at the different sites of an {open_quote}homogeneous{close_quote} region. Three versions of the regional bootstrap algorithm are presented and applied to the three cases of estimation-regional estimation for ungauged sites, regional estimation for gauged sites with a short record, and at-site estimation. It will be shown how at-site estimates can be used as basis for the intercomparison between the regional models. Results of the application of the bootstrap procedure, with flood data from the Provinces of Quebec and Ontario, are presented in the final section of the paper.

  11. The WMO Field Intercomparison of Rain Intensity Gauges

    NASA Astrophysics Data System (ADS)

    Lanza, Luca G.; Vuerich, E.

    2009-12-01

    The first Field Intercomparison of Rainfall Intensity (RI) gauges was organised by WMO (the World Meteorological Organisation) from October 2007 to April 2009 in Vigna di Valle, Rome (Italy). The campaign is held at the Centre of Meteorological Experimentations (ReSMA) of the Italian Meteorological Service. A group of 30 previously selected rain gauges based on different measuring principles are involved in the Intercomparison. Installation of the instruments in the field was preceded by the laboratory calibration of all submitted catching-type rain gauges at the University of Genoa. Additional meteorological sensors (ancillary information) and the observations and measurements performed by the Global Climate Observing System/Global Atmosphere Watch (GCOS/GAW) meteorological station of Vigna di Valle were analyzed as metadata. All catching-type gauges were tested after installation using a portable calibration device specifically developed at the University of Genoa, simulating an ordinary calibration inspection in the field. This paper is dedicated to the summary of preliminary results of the Intercomparison measurements. It offers a view on the main achievements expected from the Intercomparison in evaluating the performance of the instruments in field conditions. Comparison of several rain gauges demonstrated the possibility to evaluate the performance of RI gauges at one-minute resolution in time, as recommended by the WMO Commission for Instruments and Methods of Observations (WMO-CIMO). Results indicate that synchronised tipping-bucket rain gauges (TBR), using internal correction algorithms, and weighing gauges (WG) with improved dynamic stability and short step response are the most accurate gauges for one-minute RI measurements, since providing the lowest measurement uncertainty with respect to the assumed working reference.

  12. Intercomparison of TCCON and MUSICA Water Vapour Products

    NASA Astrophysics Data System (ADS)

    Weaver, D.; Strong, K.; Deutscher, N. M.; Schneider, M.; Blumenstock, T.; Robinson, J.; Notholt, J.; Sherlock, V.; Griffith, D. W. T.; Barthlott, S.; García, O. E.; Smale, D.; Palm, M.; Jones, N. B.; Hase, F.; Kivi, R.; Ramos, Y. G.; Yoshimura, K.; Sepúlveda, E.; Gómez-Peláez, Á. J.; Gisi, M.; Kohlhepp, R.; Warneke, T.; Dohe, S.; Wiegele, A.; Christner, E.; Lejeune, B.; Demoulin, P.

    2014-12-01

    We present an intercomparison between the water vapour products from the Total Carbon Column Observing Network (TCCON) and the MUlti-platform remote Sensing of Isotopologues for investigating the Cycle of Atmospheric water (MUSICA), two datasets from ground-based Fourier Transform InfraRed (FTIR) spectrometers with good global representation. Where possible, comparisons to radiosondes are also included. The near-infrared TCCON measurements are optimized to provide precise monitoring of greenhouse gases for carbon cycle studies; however, TCCON's retrievals also produce water vapour products. The mid-infrared MUSICA products result from retrievals optimized to give precise and accurate information about H2O, HDO, and δD. The MUSICA water vapour products have been validated by extensive intercomparisons with H2O and δD in-situ measurements made from ground, radiosonde, and aircraft (Schneider et al. 2012, 2014), as well as by intercomparisons with satellite-based H2O and δD remote sensing measurements (Wiegele et al., 2014). This dataset provides a valuable reference point for other measurements of water vapour. This study is motivated by the limited intercomparisons performed for TCCON water vapour products and limited characterisation of their uncertainties. We compare MUSICA and TCCON products to assess the potential for TCCON measurements to contribute to studies of the water cycle, water vapour's role in climate and use as a tracer for atmospheric dynamics, and to evaluate the performance of climate models. The TCCON and MUSICA products result from measurements taken using the same FTIR instruments, enabling a comparison with constant instrumentation. The retrieval techniques differ, however, in their method and a priori information. We assess the impact of these differences and characterize the comparability of the TCCON and MUSICA datasets.

  13. Inter-comparison between AIRS and IASI through Retrieved Parameters

    NASA Technical Reports Server (NTRS)

    Zhou, Daniel K.; Larar, Allen M.; Smith, William L.; Taylor, Jonathan P.; Schluessel, Peter; Strow, L. Larrabee; Mango, Steve

    2008-01-01

    A State-of-the-art retrieval algorithm dealing with all-weather conditions has been applied to satellite/aircraft instruments retrieving cloud/surface and atmospheric conditions. High quality retrievals have been achieved from IASI data. Surface, cloud, and atmospheric structure and variation are well captured by IASI measurements and/or retrievals. The same retrieval algorithm is also applied to AIRS for retrieval inter-comparison. Both AIRS and IASI have a similar FOV size but AIRS has a higher horizontal resolution. AIRS data can be interpolated to IASI horizontal resolution for inter-comparison at the same geophysical locations, however a temporal variation between AIRS and IASI observations need to be considered. JAIVEx has employed aircraft to obtain the atmospheric variation filling the temporal gap between two satellites. First results show that both AIRS and IASI have a very similar vertical resolving power, atmospheric conditions are well captured by both instruments, and radiances are well calibrated. AIRS data shown in retrievals (e.g., surface emissivity and moisture) have a relatively higher noise level. Since the this type of retrieval is very sensitive to its radiance quality, retrieval products inter-comparison is an effective way to identify/compare their radiance quality, in terms of a combination of spectral resolution and noise level, and to assess instrument performance. Additional validation analyses are needed to provide more-definitive conclusions.

  14. EARLINET instrument intercomparison campaigns: overview on strategy and results

    NASA Astrophysics Data System (ADS)

    Wandinger, Ulla; Freudenthaler, Volker; Baars, Holger; Amodeo, Aldo; Engelmann, Ronny; Mattis, Ina; Groß, Silke; Pappalardo, Gelsomina; Giunta, Aldo; D'Amico, Giuseppe; Chaikovsky, Anatoli; Osipenko, Fiodor; Slesar, Alexander; Nicolae, Doina; Belegante, Livio; Talianu, Camelia; Serikov, Ilya; Linné, Holger; Jansen, Friedhelm; Apituley, Arnoud; Wilson, Keith M.; de Graaf, Martin; Trickl, Thomas; Giehl, Helmut; Adam, Mariana; Comerón, Adolfo; Muñoz-Porcar, Constantino; Rocadenbosch, Francesc; Sicard, Michaël; Tomás, Sergio; Lange, Diego; Kumar, Dhiraj; Pujadas, Manuel; Molero, Francisco; Fernández, Alfonso J.; Alados-Arboledas, Lucas; Bravo-Aranda, Juan Antonio; Navas-Guzmán, Francisco; Guerrero-Rascado, Juan Luis; José Granados-Muñoz, María; Preißler, Jana; Wagner, Frank; Gausa, Michael; Grigorov, Ivan; Stoyanov, Dimitar; Iarlori, Marco; Rizi, Vincenco; Spinelli, Nicola; Boselli, Antonella; Wang, Xuan; Lo Feudo, Teresa; Perrone, Maria Rita; De Tomasi, Ferdinando; Burlizzi, Pasquale

    2016-03-01

    This paper introduces the recent European Aerosol Research Lidar Network (EARLINET) quality-assurance efforts at instrument level. Within two dedicated campaigns and five single-site intercomparison activities, 21 EARLINET systems from 18 EARLINET stations were intercompared between 2009 and 2013. A comprehensive strategy for campaign setup and data evaluation has been established. Eleven systems from nine EARLINET stations participated in the EARLINET Lidar Intercomparison 2009 (EARLI09). In this campaign, three reference systems were qualified which served as traveling standards thereafter. EARLINET systems from nine other stations have been compared against these reference systems since 2009. We present and discuss comparisons at signal and at product level from all campaigns for more than 100 individual measurement channels at the wavelengths of 355, 387, 532, and 607 nm. It is shown that in most cases, a very good agreement of the compared systems with the respective reference is obtained. Mean signal deviations in predefined height ranges are typically below ±2 %. Particle backscatter and extinction coefficients agree within ±2 × 10-4 km-1 sr-1 and ± 0.01 km-1, respectively, in most cases. For systems or channels that showed larger discrepancies, an in-depth analysis of deficiencies was performed and technical solutions and upgrades were proposed and realized. The intercomparisons have reinforced confidence in the EARLINET data quality and allowed us to draw conclusions on necessary system improvements for some instruments and to identify major challenges that need to be tackled in the future.

  15. EARLINET instrument intercomparison campaigns: overview on strategy and results

    NASA Astrophysics Data System (ADS)

    Wandinger, U.; Freudenthaler, V.; Baars, H.; Amodeo, A.; Engelmann, R.; Mattis, I.; Groß, S.; Pappalardo, G.; Giunta, A.; D'Amico, G.; Chaikovsky, A.; Osipenko, F.; Slesar, A.; Nicolae, D.; Belegante, L.; Talianu, C.; Serikov, I.; Linné, H.; Jansen, F.; Apituley, A.; Wilson, K. M.; de Graaf, M.; Trickl, T.; Giehl, H.; Adam, M.; Comerón, A.; Muñoz, C.; Rocadenbosch, F.; Sicard, M.; Tomás, S.; Lange, D.; Kumar, D.; Pujadas, M.; Molero, F.; Fernández, A. J.; Alados-Arboledas, L.; Bravo-Aranda, J. A.; Navas-Guzmán, F.; Guerrero-Rascado, J. L.; Granados-Muñoz, M. J.; Preißler, J.; Wagner, F.; Gausa, M.; Grigorov, I.; Stoyanov, D.; Iarlori, M.; Rizi, V.; Spinelli, N.; Boselli, A.; Wang, X.; Lo Feudo, T.; Perrone, M. R.; De Tomasi, F.; Burlizzi, P.

    2015-10-01

    This paper introduces the recent EARLINET quality-assurance efforts at instrument level. Within two dedicated campaigns and five single-site intercomparison activities 21 EARLINET systems from 18 EARLINET stations were intercompared between 2009 and 2013. A comprehensive strategy for campaign setup and data evaluation has been established. Eleven systems from nine EARLINET stations participated in the EARLINET Lidar Intercomparison 2009 (EARLI09). In this campaign, three reference systems were qualified which served as traveling standards thereafter. EARLINET systems from nine other stations have been compared against these reference systems since 2009. We present and discuss comparisons at signal and at product level from all campaigns for more than 100 individual measurement channels at the wavelengths of 355, 387, 532 and 607 nm. It is shown that in most cases a very good agreement of the compared systems with the respective reference is obtained. Mean signal deviations in pre-defined height ranges are typically below ±2 %. Particle backscatter and extinction coefficients agree within ±2 × 10-4 km-1 sr-1 and ± 0.01 km-1, respectively, in most cases. For systems or channels that showed larger discrepancies, an in-depth analysis of deficiences was performed and technical solutions and upgrades were proposed and realized. The intercomparisons have reinforced the confidence in the EARLINET data quality and allowed us to draw conclusions on necessary system improvements for some instruments and to identify major challenges that need to be tackled in the future.

  16. GABLS4: a model intercomparison study in extremely stable conditions

    NASA Astrophysics Data System (ADS)

    Bazile, Eric; Le Moigne, Patrick; Couvreux, Fleur

    2016-04-01

    In polar regions and under stable stratifications, models presents large biases that are dependent upon the parametrizations used for the surface and boundary layers (Holtslag et al., 2013). The GABLS4 inter-comparison, launched in summer 2014, aims to study the diurnal cycles over the Antarctic Plateau, focussing on the boundary layer characteristics and the coupling with the surface in strong stability. For this, the observation site of Dome C on the Antarctic Plateau was chosen mainly for two reasons: the availability of the on-site measurements from a 45-m tower and a homogeneous surface with a low conductivity such as snow on a flat topography. The inter-comparison will consist of 3 inter-comparisons : Single Column Model (SCM), Large Eddy Simulation (LES) and land-snow model (LSM). It is organized in two steps. The first one is dedicated to the LSM and the SCM with an interactive surface (snow) scheme. Then, in the second one, the observed surface temperature will be prescribed in the SCM and in the LES models. A large variability in surface fluxes was highlighted in all types of simulations with variations about 30W/m2 during daytime and night-time which is about 100% of the ensemble mean value. After a rapid overview of the setup, we will focus on the SCM results and how the results are sensitive to the surface characteristics and the vertical resolution.

  17. Aflatoxin B1 in peanut meal reference materials: intercomparisons of methods.

    PubMed

    Van Egmond, H P; Wagstaffe, P J

    1989-01-01

    The Community Bureau of Reference (BCR) is preparing a series of animal feed reference materials to provide a basis for analytical quality assurance for aflatoxin B1 analysis, a problem of particular importance in view of Community legislation. Before reference values can be assigned to the reference materials the major errors in the underlying measurements must be identified and reduced. This paper presents the results of two intercomparison exercises involving some 20 European laboratories who applied a wide variety of analytical methods. It is shown that the major source of error and discrepancy is connected with incomplete extraction and/or losses during clean-up and that, provided correction for recovery/background interference is made, many methods can achieve acceptable accuracy. Sources of error and their control are discussed, and essential details of the methods used are presented. It is concluded that analytical QA is more important than the use of standardized methods when a high degree of accuracy and comparability are required. PMID:2498137

  18. The NDSC ozone and temperature lidar alogorithm intercomparison ubutuatuve (A2I): project overview

    NASA Technical Reports Server (NTRS)

    LeBlanc, Thierry; McDermid, Iain S.; Von der Gathen, P.; Neuber, R.; Muller, M.; Immler, F.; Schrems, O.; Stebel, K.; Hansen, G.; Steinbrecht, W.; Claude, H.; Pazmino, A.; Godin-Beekmann, S.; Ancellet, G.; Baray, P. L.; Bencherif, H.; Meijer, Y.; Swart, D.; Twigg, L.; Thayer, J.; Livingston, J.; Kekchut, P.; Hauchecorne, A.; Barnes, J. E.

    2004-01-01

    In September 2003, the Lidar Working Group (LWG) of the Network for Detection of Stratospheric Change (NDSC) initiated an extensive project to compare the ozone and temperature algorithms used within NDSC. This initiative, referred to later as Algorithm Intercomparison Initiative (A2I), uses simulated lidar signals to test and compare various parts of the ozone and temperature lidar algorithms. In addition to the fact that it meets the requirement of the NDSC protocols, this exercise allows the detailed assessment, by all the participants, of some of the sources and magnitudes of various uncertainties associated with the algorithms, and/or with the theoretical assumptions made in these algorithms. The outcome of the A21 is to try to find common grounds in the way ozone and temperature can be retrieved in order to reduce and possibly eradicate discrepancies due to algorithm issues alone. Specific issues such as homogenizing the choice of Rayleigh extinction cross-sections, ozone absorption cross-sections, a priori information, and the definition of the vertical resolutions are among the primary targets of the A21 outcome.

  19. Intercomparison of active and passive instruments for radon and radon progeny in North America

    SciTech Connect

    George, A.C.; Tu, Keng-Wu; Knutson, E.O.

    1995-02-01

    An intercomparison exercise for radon and radon progeny instruments and methods was held at the Environmental Measurements Laboratory (EML) from April 22--May 2, 1994. The exercise was conducted in the new EML radon test and calibration facility in which conditions of exposure are very well controlled. The detection systems of the intercompared instruments consisted of. (1) pulse ionization chambers, (2) electret ionization chambers, (3) scintillation detectors, (4) alpha particle spectrometers with silicon diodes, surface barrier or diffused junction detectors, (5) registration of nuclear tracks in solid-state materials, and (6) activated carbon collectors counted by gamma-ray spectrometry or by alpha- and beta-liquid scintillation counting. 23 private firms, government laboratories and universities participated with a 165 passive integrating devices consisting of: Activated carbon collectors, nuclear alpha track detectors and electret ionization chambers, and 11 active and passive continuous radon monitors. Five portable integrating and continuous instruments were intercompared for radon progeny. Forty grab samples for radon progeny were taken by five groups that participated in person to test and evaluate their primary instruments and methods that measure individual radon progeny and the potential alpha energy concentration (PAEC) in indoor air. Results indicate that more than 80% of the measurements for radon performed with a variety of instruments, are within {plus_minus}10% of actual value. The majority of the instruments that measure individual radon progeny and the PAEC gave results that are in good agreement with the EML reference value. Radon progeny measurements made with continuous and integrating instruments are satisfactory with room for improvement.

  20. Diet and Exercise Tips

    MedlinePlus

    ... Health News & Publications Annual Meeting Calendar Diet and Exercise Tips Diet and Exercise Tips News media interested in covering the latest ... Health Statistics concludes that 35 percent of adults exercise regularly (more than 6 of 10 don’t), ...

  1. Why Exercise Is Cool

    MedlinePlus

    ... Homework? Here's Help White House Lunch Recipes Why Exercise Is Cool KidsHealth > For Kids > Why Exercise Is ... day and your body will thank you later! Exercise Makes Your Heart Happy You may know that ...

  2. Rotator cuff exercises

    MedlinePlus

    Shoulder exercises ... A key part in your recovery is doing exercises to make the muscles and tendons in your ... for everyday tasks or sports activities Before doing exercises at home, ask your doctor or physical therapist ...

  3. Exercise and Physical Activity

    MedlinePlus

    Alzheimer ’s Caregiving Tips Exercise and Physical Activity Being active and getting exercise helps people with Alzheimer’s disease feel better. Exercise helps keep their muscles, joints, and heart in ...

  4. Exercise and immunity

    MedlinePlus

    ... know exactly if or how exercise increases your immunity to certain illnesses, but there are several theories ( ... not exercise more intensely just to increase their immunity. Heavy, long-term exercise (such as marathon running ...

  5. Anisn-Dort Neutron-Gamma Flux Intercomparison Exercise for a Simple Testing Model

    NASA Astrophysics Data System (ADS)

    Boehmer, B.; Konheiser, J.; Borodkin, G.; Brodkin, E.; Egorov, A.; Kozhevnikov, A.; Zaritsky, S.; Manturov, G.; Voloschenko, A.

    2003-06-01

    The ability of transport codes ANISN, DORT, ROZ-6, MCNP and TRAMO, as well as nuclear data libraries BUGLE-96, ABBN-93, VITAMIN-B6 and ENDF/B-6 to deliver consistent gamma and neutron flux results was tested in the calculation of a one-dimensional cylindrical model consisting of a homogeneous core and an outer zone with a single material. Model variants with H2O, Fe, Cr and Ni in the outer zones were investigated. The results are compared with MCNP-ENDF/B-6 results. Discrepancies are discussed. The specified test model is proposed as a computational benchmark for testing calculation codes and data libraries.

  6. Analysis of UK and European NOx and VOC emission scenarios in the Defra model intercomparison exercise

    NASA Astrophysics Data System (ADS)

    Derwent, Richard; Beevers, Sean; Chemel, Charles; Cooke, Sally; Francis, Xavier; Fraser, Andrea; Heal, Mathew R.; Kitwiroon, Nutthida; Lingard, Justin; Redington, Alison; Sokhi, Ranjeet; Vieno, Massimo

    2014-09-01

    Simple emission scenarios have been implemented in eight United Kingdom air quality models with the aim of assessing how these models compared when addressing whether photochemical ozone formation in southern England was NOx- or VOC-sensitive and whether ozone precursor sources in the UK or in the Rest of Europe (RoE) were the most important during July 2006. The suite of models included three Eulerian-grid models (three implementations of one of these models), a Lagrangian atmospheric dispersion model and two moving box air parcel models. The assignments as to NOx- or VOC-sensitive and to UK- versus RoE-dominant, turned out to be highly variable and often contradictory between the individual models. However, when the assignments were filtered by model performance on each day, many of the contradictions could be eliminated. Nevertheless, no one model was found to be the 'best' model on all days, indicating that no single air quality model could currently be relied upon to inform policymakers robustly in terms of NOx- versus VOC-sensitivity and UK- versus RoE-dominance on each day. It is important to maintain a diversity in model approaches.

  7. Exercise countermeasures for spaceflight.

    PubMed

    Convertino, V A; Sandler, H

    1995-01-01

    The authors present a physiological basis for the use of exercise as a weightlessness countermeasure, outline special considerations for the development of exercise countermeasures, review and evaluate exercise used during space flight, and provide new approaches and concepts for the implementation of novel exercise countermeasures for future space flight. The discussion of the physiological basis for countermeasures examines maximal oxygen uptake, blood volume, metabolic responses to work, muscle function, bone loss, and orthostatic instability. The discussion of considerations for exercise prescriptions during space flight includes operational considerations, type of exercise, fitness considerations, age and gender, and psychological considerations. The discussion of exercise currently used in space flight examines cycle ergometry, the treadmill, strength training devices, electrical stimulation, and the Penguin suit worn by Russian crews. New approaches to exercise countermeasures include twin bicycles, dynamic resistance exercisers, maximal exercise effects, grasim (gravity simulators), and the relationship between exercise and LBNP. PMID:11541470

  8. The Global Gridded Crop Model Intercomparison (GGCMI) (Invited)

    NASA Astrophysics Data System (ADS)

    Elliott, J. W.

    2013-12-01

    In 2012 AgMIP led a Global Gridded Crop Model (GGCM) Intercomparison fast-track project in coordination with the PIK-led Inter-Sectoral Impacts Model Intercomparison Project (ISI-MIP). This fast-track included 7 GGCMs and updated the state of knowledge on climate change vulnerabilities and impacts using modern global high-resolution models driven by climate model output from CMIP5. This fast-track culminated with the January 31st submission of 6 papers to a PNAS special issue. Initial results indicate the potential of global gridded crop model simulations and the need to further improve understanding of mechanisms, assumptions, and uncertainties of model design and execution; these are best addressed in a coordinated model intercomparison project at continental and global scale. In Spring 2013, we developed a new set of protocols for the next phase of the GGCMI, which will run for 3 years and include 3 overlapping stages of increasing duration: 1) Historical simulation and model evaluation 2) Analysis of model sensitivity to CTWN (carbon, temperature, water, and nitrogen) 3) Coordinated regional and global climate assessment In this talk we will summarize some key finding from the 2012 fast-track assessment and present preliminary results from Phase 2.1: Historical simulation and model evaluation. In this stage, models are being run using various observation and reanalysis-based historical weather products so that they can be evaluated over the historical period globally and in various key interest regions, so that inter-model differences can be compared against the variation induced by the choice of historical data product, and so that historical extreme events can be evaluated in a multi-model framework. The project currently includes 17 modeling groups from 11 countries, along with several other major data partners, and simulations are being performed over the Summer and Fall of 2013.

  9. Global Intercomparison of 12 Land Surface Heat Flux Estimates

    NASA Technical Reports Server (NTRS)

    Jimenez, C.; Prigent, C.; Mueller, B.; Seneviratne, S. I.; McCabe, M. F.; Wood, E. F.; Rossow, W. B.; Balsamo, G.; Betts, A. K.; Dirmeyer, P. A.; Fisher, J. B.; Jung, M.; Kanamitsu, M.; Reichle, R. H.; Reichstein, M.; Rodell, M.; Sheffield, J.; Tu, K.; Wang, K.

    2011-01-01

    A global intercomparison of 12 monthly mean land surface heat flux products for the period 1993-1995 is presented. The intercomparison includes some of the first emerging global satellite-based products (developed at Paris Observatory, Max Planck Institute for Biogeochemistry, University of California Berkeley, University of Maryland, and Princeton University) and examples of fluxes produced by reanalyses (ERA-Interim, MERRA, NCEP-DOE) and off-line land surface models (GSWP-2, GLDAS CLM/ Mosaic/Noah). An intercomparison of the global latent heat flux (Q(sub le)) annual means shows a spread of approx 20 W/sq m (all-product global average of approx 45 W/sq m). A similar spread is observed for the sensible (Q(sub h)) and net radiative (R(sub n)) fluxes. In general, the products correlate well with each other, helped by the large seasonal variability and common forcing data for some of the products. Expected spatial distributions related to the major climatic regimes and geographical features are reproduced by all products. Nevertheless, large Q(sub le)and Q(sub h) absolute differences are also observed. The fluxes were spatially averaged for 10 vegetation classes. The larger Q(sub le) differences were observed for the rain forest but, when normalized by mean fluxes, the differences were comparable to other classes. In general, the correlations between Q(sub le) and R(sub n) were higher for the satellite-based products compared with the reanalyses and off-line models. The fluxes were also averaged for 10 selected basins. The seasonality was generally well captured by all products, but large differences in the flux partitioning were observed for some products and basins.

  10. Exercise Is Medicine.

    ERIC Educational Resources Information Center

    Elrick, Harold

    1996-01-01

    Suggests that exercise should be the first-line therapy for preventing and treating many common diseases; however, physicians need more training in how best to use exercise therapy. The paper explains the power of exercise and discusses how to motivate individuals to start safe, enjoyable, and life-saving exercise routines. (SM)

  11. Kegel Exercise Tips

    MedlinePlus

    ... PDF, 345 KB) Alternate Language URL Español Kegel Exercise Tips Page Content What are Kegel exercises? To do Kegel exercises, you just squeeze your ... help with your bladder control. How do you exercise your pelvic muscles? Find the right muscles. Try ...

  12. An intercomparison of hydrological network-design technologies

    USGS Publications Warehouse

    Moss, M.E.; Tasker, Gary D.

    1991-01-01

    Two network-design technologies are compared by random sub-sampling of actual streamflow data. The technologies Network Analysis for Regional Information (NARI) and Network Analysis Using Generalized Least Squares (NAUGLS), have a common objective, viz. to maximize regional information within a limited budget and time horizon. The data used for intercomparison are from a network of 146 streamgauges in the central part of the USA. In general, the results for the illustrative example indicate that the NAUGLS method conveys more information than the NARI method to the network designer interested in maximizing regional information about mean annual flows with a limited budget. -Authors

  13. Atmospheric measurements of total OH reactivity: Intercomparison of the pump-probe technique and the comparative reactivity method

    NASA Astrophysics Data System (ADS)

    Dusanter, Sebastien; Hansen, Robert; Leonardis, Thierry; Schoemaecker, Coralie; Blocquet, Marion; Fittschen, Christa; Hanoune, Benjamin; Sinha, Vinayak; Stevens, Philip; Locoge, Nadine

    2013-04-01

    The hydroxyl radical (OH) drives the oxidation of organic trace gases that can lead to the production of ozone and secondary organic aerosols in the atmosphere. A complete understanding of the sources and sinks of OH is therefore important to address issues related to both air quality and climate change. However, recent measurements of total OH reactivity [1-2], which is the inverse of the OH lifetime, have pointed out that our understanding of OH sinks is still incomplete and important reactive trace gases have not yet been identified. These measurements of total OH reactivity are of particular interest since they provide a critical test of our understanding of the OH budget. Three techniques are available to measure the total OH reactivity, including the total OH loss rate method [3], the pump-probe method [4], and the comparative reactivity method (CRM) [5]. While the first two methods are based on direct measurements of OH decays using laser-induced fluorescence instruments, the CRM is based on a different approach in which a tracer molecule is detected instead of OH to determine the ambient OH loss rate. As these instruments were deployed in different field campaigns, intercomparison exercises would be useful to ensure the accuracy of the measurements. However, such intercomparisons have not yet been published. An informal intercomparison involving a CRM instrument from the Ecole des Mines de Douai (EMD) and a pump-probe instrument from the laboratory Physicochimie des Processus de Combustion et de l'Atmosphere (PC2A) took place in an urban environment at the university of Lille (France). The two OH reactivity instruments measured continuously side by side for a duration of two weeks. Collocated measurements of trace gases were also performed using O3, NOx and SO2 monitors, as well as two automated chromatographic instruments capable of measuring more than 50 volatile organic compounds (VOC). We will present cross calibrations of the two OH reactivity

  14. The Continual Intercomparison of Radiation Codes: Results from Phase I

    SciTech Connect

    Oreopoulos, L.; Mlawer, Eli J.; Delamere, Jennifer; Shippert, Timothy R.; Cole, Jason; Fomin, Boris; Iacono, Michael J.; Jin, Zhonghai; Li, Jiangning; Manners, James; Raisanen, Petri; Rose, Fred; Zhang, Yuanchong; Wilson, Michael J.; Rossow, William B.

    2012-01-01

    We present results from Phase I of the Continual Intercomparison of Radiation Codes (CIRC), intended as an evolving and regularly updated reference source for evaluation of radiative transfer (RT) codes used in Global Climate Models. CIRC differs from previous intercomparisons in that it relies on an observationally validated catalogue of cases. The seven CIRC Phase I baseline cases, five cloud-free, and two with overcast liquid clouds, are built around observations by the Atmospheric Radiation Measurements (ARM) program that satisfy the goals of Phase I, namely to examine radiative transfer (RT) model performance in realistic, yet not overly complex, atmospheric conditions. In addition to the seven baseline cases, additional idealized "subcases" are also examined to facilitate intrepretation of the causes of model errors. In addition to summarizing individual model performance with respect to reference line-by-line calculations and inter-model differences, we also highlight RT model behavior for conditions of doubled CO2, aspects of utilizing a spectral specification of surface albedo, and the impact of the inclusion of scattering in the thermal infrared. Our analysis suggests that RT models should work towards improving their calculation of diffuse shortwave flux, shortwave absorption, treatment of spectral surface albedo, and shortwave CO2 forcing. On the other hand, LW calculations appear to be significantly closer to the reference results. By enhancing the range of conditions under which participating codes are tested, future CIRC phases will hopefully allow even more rigorous examination of RT code performance.

  15. IPRT polarized radiative transfer model intercomparison project - Phase A

    NASA Astrophysics Data System (ADS)

    Emde, Claudia; Barlakas, Vasileios; Cornet, Céline; Evans, Frank; Korkin, Sergey; Ota, Yoshifumi; Labonnote, Laurent C.; Lyapustin, Alexei; Macke, Andreas; Mayer, Bernhard; Wendisch, Manfred

    2015-10-01

    The polarization state of electromagnetic radiation scattered by atmospheric particles such as aerosols, cloud droplets, or ice crystals contains much more information about the optical and microphysical properties than the total intensity alone. For this reason an increasing number of polarimetric observations are performed from space, from the ground and from aircraft. Polarized radiative transfer models are required to interpret and analyse these measurements and to develop retrieval algorithms exploiting polarimetric observations. In the last years a large number of new codes have been developed, mostly for specific applications. Benchmark results are available for specific cases, but not for more sophisticated scenarios including polarized surface reflection and multi-layer atmospheres. The International Polarized Radiative Transfer (IPRT) working group of the International Radiation Commission (IRC) has initiated a model intercomparison project in order to fill this gap. This paper presents the results of the first phase A of the IPRT project which includes ten test cases, from simple setups with only one layer and Rayleigh scattering to rather sophisticated setups with a cloud embedded in a standard atmosphere above an ocean surface. All scenarios in the first phase A of the intercomparison project are for a one-dimensional plane-parallel model geometry. The commonly established benchmark results are available at the IPRT website.

  16. The Continuous Intercomparison of Radiation Codes (CIRC): Phase I Cases

    NASA Technical Reports Server (NTRS)

    Oreopoulos, Lazaros; Mlawer, Eli; Delamere, Jennifer; Shippert, Timothy; Turner, David D.; Miller, Mark A.; Minnis, Patrick; Clough, Shepard; Barker, Howard; Ellingson, Robert

    2007-01-01

    CIRC aspires to be the successor to ICRCCM (Intercomparison of Radiation Codes in Climate Models). It is envisioned as an evolving and regularly updated reference source for GCM-type radiative transfer (RT) code evaluation with the principle goal to contribute in the improvement of RT parameterizations. CIRC is jointly endorsed by DOE's Atmospheric Radiation Measurement (ARM) program and the GEWEX Radiation Panel (GRP). CIRC's goal is to provide test cases for which GCM RT algorithms should be performing at their best, i.e, well characterized clear-sky and homogeneous, overcast cloudy cases. What distinguishes CIRC from previous intercomparisons is that its pool of cases is based on observed datasets. The bulk of atmospheric and surface input as well as radiative fluxes come from ARM observations as documented in the Broadband Heating Rate Profile (BBHRP) product. BBHRP also provides reference calculations from AER's RRTM RT algorithms that can be used to select the most optimal set of cases and to provide a first-order estimate of our ability to achieve radiative flux closure given the limitations in our knowledge of the atmospheric state.

  17. The T-REX valley wind intercomparison project

    SciTech Connect

    Schmidli, J; Billings, B J; Burton, R; Chow, F K; De Wekker, S; Doyle, J D; Grubisic, V; Holt, T R; Jiang, Q; Lundquist, K A; Ross, A N; Sheridan, P; Vosper, S; Whiteman, C D; Wyszogrodzki, A A; Zaengl, G; Zhong, S

    2008-08-07

    An accurate simulation of the evolution of the atmospheric boundary layer is very important, as the evolution of the boundary layer sets the stage for many weather phenomena, such as deep convection. Over mountain areas the evolution of the boundary layer is particularly complex, due to the nonlinear interaction between boundary layer turbulence and thermally-induced mesoscale wind systems, such as the slope and valley winds. As the horizontal resolution of operational forecasts progresses to finer and finer resolution, more and more of the thermally-induced mesoscale wind systems can be explicitly resolved, and it is very timely to document the current state-of-the-art of mesoscale models at simulating the coupled evolution of the mountain boundary layer and the valley wind system. In this paper we present an intercomparison of valley wind simulations for an idealized valley-plain configuration using eight state-of-the-art mesoscale models with a grid spacing of 1 km. Different sets of three-dimensional simulations are used to explore the effects of varying model dynamical cores and physical parameterizations. This intercomparison project was conducted as part of the Terrain-induced Rotor Experiment (T-REX; Grubisic et al., 2008).

  18. An overview of sensor calibration inter-comparison and applications

    USGS Publications Warehouse

    Xiong, Xiaoxiong; Cao, Changyong; Chander, Gyanesh

    2010-01-01

    Long-term climate data records (CDR) are often constructed using observations made by multiple Earth observing sensors over a broad range of spectra and a large scale in both time and space. These sensors can be of the same or different types operated on the same or different platforms. They can be developed and built with different technologies and are likely operated over different time spans. It has been known that the uncertainty of climate models and data records depends not only on the calibration quality (accuracy and stability) of individual sensors, but also on their calibration consistency across instruments and platforms. Therefore, sensor calibration inter-comparison and validation have become increasingly demanding and will continue to play an important role for a better understanding of the science product quality. This paper provides an overview of different methodologies, which have been successfully applied for sensor calibration inter-comparison. Specific examples using different sensors, including MODIS, AVHRR, and ETM+, are presented to illustrate the implementation of these methodologies.

  19. Proxy benchmarks for intercomparison of 8.2 ka simulations

    NASA Astrophysics Data System (ADS)

    Morrill, C.; Anderson, D. M.; Bauer, B. A.; Buckner, R.; Gille, E. P.; Gross, W. S.; Hartman, M.; Shah, A.

    2012-08-01

    The Paleoclimate Modelling Intercomparison Project (PMIP3) now includes the 8.2 ka event as a test of model sensitivity to North Atlantic freshwater forcing. To provide benchmarks for intercomparison, we compiled and analyzed high-resolution records spanning this event. Two previously-described anomaly patterns that emerge are cooling around the North Atlantic and drier conditions in the Northern Hemisphere tropics. Newer to this compilation are more robustly-defined wetter conditions in the Southern Hemisphere tropics and regionally-limited warming in the Southern Hemisphere. Most anomalies around the globe lasted on the order of 100 to 150 yr. More quantitative reconstructions are now available and indicate cooling of 1.0 to 1.2 °C and a ~20% decrease in precipitation in parts of Europe, as well as spatial gradients in δ18O from the high to low latitudes. Unresolved questions remain about the seasonality of the climate response to freshwater forcing and the extent to which the bipolar seesaw operated in the early Holocene.

  20. Proxy benchmarks for intercomparison of 8.2 ka simulations

    NASA Astrophysics Data System (ADS)

    Morrill, C.; Anderson, D. M.; Bauer, B. A.; Buckner, R.; Gille, E. P.; Gross, W. S.; Hartman, M.; Shah, A.

    2013-02-01

    The Paleoclimate Modelling Intercomparison Project (PMIP3) now includes the 8.2 ka event as a test of model sensitivity to North Atlantic freshwater forcing. To provide benchmarks for intercomparison, we compiled and analyzed high-resolution records spanning this event. Two previously-described anomaly patterns that emerge are cooling around the North Atlantic and drier conditions in the Northern Hemisphere tropics. Newer to this compilation are more robustly-defined wetter conditions in the Southern Hemisphere tropics and regionally-limited warming in the Southern Hemisphere. Most anomalies around the globe lasted on the order of 100 to 150 yr. More quantitative reconstructions are now available and indicate cooling of ~ 1 °C and a ~ 20% decrease in precipitation in parts of Europe as well as spatial gradients in δ18O from the high to low latitudes. Unresolved questions remain about the seasonality of the climate response to freshwater forcing and the extent to which the bipolar seesaw operated in the early Holocene.

  1. Exercise and the asthmatic.

    PubMed

    Bundgaard, A

    1985-01-01

    Physical exercise is not hazardous to asthmatics. Some asthmatics may benefit from physical training, and almost all asthmatics can perform any kind of physical exercise. Free running was earlier thought to induce more asthma than swimming, for example; however, when ventilation is identical during running and swimming, the exercise-induced asthma will also be the same. Hyperventilation alone is as good as physical exercise to induce exercise-induced asthma. If the physical exercise provokes an asthmatic attack, this is most often easily reversed by inhaled beta 2-agonists. Pretreatment of exercise-induced asthma is most efficient by inhaled beta 2-agonist; orally dosed beta 2-agonist is not as efficient as inhaled beta 2-agonist in the pretreatment of exercise-induced asthma. Inhaled sodium cromoglycate diminishes exercise-induced asthma, and the effect seems to be better in children than in adults. Inhaled steroids have no immediate effect on exercise-induced asthma, but long term treatment with steroids diminishes exercise-induced asthma. The pathogenesis of exercise-induced asthma remains obscure. If the water content is low in the inhaled air, e.g. in cold air, the changes in ventilatory capacity following exercise. will be greater than when the exercise is performed while inhaling hot air with high humidity. Almost all asthmatics present changes in the ventilatory capacity following exercise. Seasonal changes in exercise-induced asthma are only present in asthmatics with seasonal allergies, e.g. pollen allergy. No diurnal variation is found in exercise-induced asthma. Asthmatics can do any form of physical exercise. Almost all asthmatics can prevent major changes in ventilatory capacity by pretreatment of exercise-induced asthma or be treated for exercise-induced asthma during the physical activity so that they will not suffer from asthma while performing physical exercise. Asthmatics who have been successfully treated for exercise-induced asthma can do

  2. Exercise training in asthma.

    PubMed

    Satta, A

    2000-12-01

    Asthma is a chronic disease that is often limiting the exercise capacity. Rehabilitation programs are recommended and widely applied in asthmatic patients, and exercise prescription is a keystone of these programs. The impairment of exercise performance in asthmatics, the role of exercise training in such patients, the mechanisms of its beneficial effects and the suggested programs are discussed in a review, accordingly to the current evidence and available data in scientific literature. Exercise performance is impaired in most asthmatics. There is no conclusive evidence that asthma may involve a ventilatory limitation to exercise. The lesser fitness in asthmatics seems mainly due to inactivity and sedentary lifestyle. Exercise induced asthma (EIA) is a significant problem, and the best approach to minimise its effects on exercise capacity is prevention. Exercise training has been proved to have health-related benefits and to improve the quality of life. There is substantial evidence that exercise training increases exercise performance and fitness in asthmatics. It is still unclear whether physical training improves pulmonary function and bronchial responsiveness. Since asthma ranges widely, exercise prescription varies for each patient. The proper selection of the patients and the choice of exercise programs are the steps required. Accordingly with the severity of the disease, exercise strategies may range from sports activities to, when the disease is severe, inpatient hospital programs that overlap with COPD rehabilitation. Further research to clarify some aspects (effects on pulmonary function and EIA, outcomes, cost-benefit relationship) is necessary. PMID:11296996

  3. Towards a consistent eddy-covariance processing: an intercomparison of EddyPro and TK3

    NASA Astrophysics Data System (ADS)

    Fratini, G.; Mauder, M.

    2014-03-01

    A comparison of two popular eddy-covariance (EC) software packages is presented, namely EddyPro and TK3. Two about one-month long test datasets were processed, representing typical instrumental setups, i.e. CSAT3/LI-7500 above grassland and Solent R3/LI-6262 above a forest. The resulting fluxes and quality flags were compared. Achieving a satisfying agreement and understanding residual discrepancies required several iterations and interventions of different nature, spanning from simple software reconfiguration to actual code manipulations. In this paper, we document our comparison exercise and show that the two software packages can provide utterly satisfying agreement when properly configured. Our main aim, however, is to stress the complexity of performing a rigorous comparison of EC software. We show that discriminating actual discrepancies in the results from inconsistencies in the software configuration requires deep knowledge of both software packages and of the eddy-covariance method itself. In some instances, it may be even beyond the possibility of the investigator who does not control the source code. Being the developers of EddyPro and TK3, we could discuss the comparison at all levels of details and this proved necessary to achieve a full understanding. As a further consequence, we also suggest that, to the aim of assuring consistency and comparability of centralized flux databases, and for a confident use of eddy fluxes in synthesis studies on the regional, continental and global scale, researchers rely on established software, notably those that have been extensively validated in documented intercomparisons.

  4. Towards a consistent eddy-covariance processing: an intercomparison of EddyPro and TK3

    NASA Astrophysics Data System (ADS)

    Fratini, G.; Mauder, M.

    2014-07-01

    A comparison of two popular eddy-covariance software packages is presented, namely, EddyPro and TK3. Two approximately 1-month long test data sets were processed, representing typical instrumental setups (i.e., CSAT3/LI-7500 above grassland and Solent R3/LI-6262 above a forest). The resulting fluxes and quality flags were compared. Achieving a satisfying agreement and understanding residual discrepancies required several iterations and interventions of different nature, spanning from simple software reconfiguration to actual code manipulations. In this paper, we document our comparison exercise and show that the two software packages can provide utterly satisfying agreement when properly configured. Our main aim, however, is to stress the complexity of performing a rigorous comparison of eddy-covariance software. We show that discriminating actual discrepancies in the results from inconsistencies in the software configuration requires deep knowledge of both software packages and of the eddy-covariance method. In some instances, it may be even beyond the possibility of the investigator who does not have access to and full knowledge of the source code. Being the developers of EddyPro and TK3, we could discuss the comparison at all levels of details and this proved necessary to achieve a full understanding. As a result, we suggest that researchers are more likely to get comparable results when using EddyPro (v5.1.1) and TK3 (v3.11) - at least with the setting presented in this paper - than they are when using any other pair of EC software which did not undergo a similar cross-validation. As a further consequence, we also suggest that, to the aim of assuring consistency and comparability of centralized flux databases, and for a confident use of eddy fluxes in synthesis studies on the regional, continental and global scale, researchers only rely on software that have been extensively validated in documented intercomparisons.

  5. RADIO-ACTIVE TRANSDUCER

    DOEpatents

    Wanetick, S.

    1962-03-01

    ABS>ure the change in velocity of a moving object. The transducer includes a radioactive source having a collimated beam of radioactive particles, a shield which can block the passage of the radioactive beam, and a scintillation detector to measure the number of radioactive particles in the beam which are not blocked by the shield. The shield is operatively placed across the radioactive beam so that any motion normal to the beam will cause the shield to move in the opposite direction thereby allowing more radioactive particles to reach the detector. The number of particles detected indicates the acceleration. (AEC)

  6. Writing Exercises from "Exercise Exchange." Volume II.

    ERIC Educational Resources Information Center

    Duke, Charles R., Ed.

    Reflecting current practices in the teaching of writing, the exercises in this compilation were drawn from the journal "Exercise Exchange." The articles are arranged into six sections: sources for writing; prewriting; modes for writing; writing and reading; language, mechanics, and style; and revising, responding, and evaluating. Among the topics…

  7. Why Exercise Is Wise

    MedlinePlus

    ... for Parents for Kids for Teens Teens Home Body Mind Sexual Health Food & Fitness Diseases & Conditions Infections Q& ... the reasons: Exercise benefits every part of the body, including the mind. Exercising causes the body to produce endorphins, chemicals ...

  8. Learn to love exercise

    MedlinePlus

    ... can join. Choose your sweet spot. Do you love being outdoors? Choose activities that get you outside, ... Council on Exercise. 5 Tips for Learning to Love Exercise (or at Least Develop a Crush on ...

  9. Clinical Applications for Exercise.

    ERIC Educational Resources Information Center

    Goldstein, David

    1989-01-01

    Patients with chronic conditions such as coronary artery disease, hypertension, diabetes, and obesity might benefit from prescribed exercise. Although exercise does not reverse pathologic changes, it may play a role in disease management. (JD)

  10. Exercise and Physical Fitness

    MedlinePlus

    ... Increase your chances of living longer Fitting regular exercise into your daily schedule may seem difficult at ... fine. The key is to find the right exercise for you. It should be fun and should ...

  11. Exercise and Osteoporosis

    MedlinePlus

    ... My Go4Life Get Free Stuff Be a Partner Exercise and Osteoporosis Osteoporosis is a disease that weakens ... calcium and vitamin D. Include regular weight-bearing exercise in your lifestyle. Stop smoking. Limit how much ...

  12. Learn to love exercise

    MedlinePlus

    ... mix it up. For example, you might play golf on a Saturdays, take tango classes on Mondays, ... American Council on Exercise. 5 Tips for Learning to Love Exercise (or at Least Develop a Crush on It). ... ...

  13. Kids and Exercise

    MedlinePlus

    ... Kids For Parents MORE ON THIS TOPIC Cold-Weather Sports and Your Family How Can Families Be ... a Fit Kid Why Exercise Is Cool Cold-Weather Sports Strength Training Weight Management: Strength Training Exercises ( ...

  14. Exercising on a budget

    MedlinePlus

    ... use proper form, go to the online exercise library at the American Council on Exercise. They also have sample workout routines you can try. Look for low-cost fitness options Many sports and activities are free ...

  15. Exercise and Asthma

    MedlinePlus

    ... Issues Listen Español Text Size Email Print Share Exercise and Asthma Page Content Article Body Almost every ... children more likely to develop asthma. How does exercise cause asthma symptoms? The symptoms of asthma are ...

  16. Exercise for Seniors

    MedlinePlus

    Exercise and physical activity are good for just about everyone, including older adults. There are four main ... jogging, dancing, swimming, and biking are examples. Strength exercises make your muscles stronger. Lifting weights or using ...

  17. Diet and Exercise

    MedlinePlus

    ... Types Risk Factors Prevention & Early Detection Diet And Exercise Transplant recipients need to be aware of the ... help arrange for counseling and other support services. Exercise After a Transplant Most people are weak after ...

  18. Exercise during Pregnancy

    MedlinePlus

    ... Pregnancy Patient Education FAQs Exercise During Pregnancy Patient Education Pamphlets - Spanish Exercise During Pregnancy FAQ119, May 2016 PDF Format ... Your Practice Patient Safety & Quality Payment Reform (MACRA) Education & Events Annual ... Pamphlets Teen Health About ACOG About Us Leadership & ...

  19. Exercise After Pregnancy

    MedlinePlus

    ... Pregnancy Patient Education FAQs Exercise After Pregnancy Patient Education Pamphlets - Spanish Exercise After Pregnancy FAQ131, June 2015 PDF Format ... Your Practice Patient Safety & Quality Payment Reform (MACRA) Education & Events Annual ... Pamphlets Teen Health About ACOG About Us Leadership & ...

  20. Exercise for Seniors

    MedlinePlus

    ... and heart rate. Brisk walking or jogging, dancing, swimming, and biking are examples. Strength exercises make your muscles stronger. Lifting weights or using a resistance band can build strength. Balance exercises help prevent ...

  1. The 1987 Federal field exercise: The DOE experience

    SciTech Connect

    Adler, M.V.; Gant, K.S.

    1989-06-01

    The second full-scale field exercise of the Federal Radiological Emergency Response Plan (FRERP) was held at the Zion Nuclear Power Station, Zion, Illinois, in June 1987. The exercise incorporated the annual compliance exercise for the Zion plant and involved the operating utility, Commonwealth Edison Company, the states of Illinois and Wisconsin, local governments, volunteer groups, and representatives from 12 federal agencies. The 3-day exercise was played from many locations in the Zion area; Springfield, Illinois; Madison, Wisconsin; and Washington, DC. Approximately 1000 people participated in the exercise, which used a scenario in which an accident at the plant resulted in the release of radioactive material outside the plant boundary. The US Department of Energy (DOE) had major responsibilities during the planning, playing, and critiquing of the exercise; these functions are outlined in the report. This document describes the DOE participation in the planning and response during the exercise. During a radiological emergency, the FRERP gives DOE the responsibility for coordinating the federal radiological monitoring and assessment activities in support of the states and the cognizant federal agency. At Zion, a self-sufficient Federal Radiological Monitoring and Assessment Center was established by DOE at a nearby fairground in which over 200 people from DOE, the two states, and other federal agencies participated. Before the field exercise, a tabletop exercise and a dry run were held for training purposes. 5 refs., 6 figs.

  2. Effect of background and transport dose on the results of the personal dose equivalent Hp(10) measurements in photon fields obtained during the intercomparison 2013 of the African region.

    PubMed

    Arib, M; Herrati, A; Dari, F; Lounis-Mokrani, Z

    2015-12-01

    As part of the intercomparison on the measurement of personal dose equivalent Hp(10), jointly organised by the International Atomic Energy Agency and the Algerian Secondary Standard Dosimetry Laboratory, for the African region, up to 12 dosemeters were added to the packages of the 28 participants to evaluate the background and transport dose (BGTD), received by the dosemeters before and after their irradiation at the SSDL (environmental irradiations, scanning process at the airports, etc.). Out of the 28 participants, only 17 reported the corresponding BGTD measured values, which lied between 0.03 and 0.8 mSv. The mean measured value of BG was (0.25±0.14) mSv, which is significantly high compared with the lowest dose value used in the intercomparison exercise. The BGTD correction shifted the overall results of the intercomparison from an overestimation of dose (∼8 % before applying BGT dose correction) to an underestimation of dose (-9 % after correction). The measurement protocol and the detailed analysis of the results and applied corrections are discussed in this paper. PMID:25433048

  3. The InterFrost benchmark of Thermo-Hydraulic codes for cold regions hydrology - first inter-comparison phase results

    NASA Astrophysics Data System (ADS)

    Grenier, Christophe; Rühaak, Wolfram

    2016-04-01

    Climate change impacts in permafrost regions have received considerable attention recently due to the pronounced warming trends experienced in recent decades and which have been projected into the future. Large portions of these permafrost regions are characterized by surface water bodies (lakes, rivers) that interact with the surrounding permafrost often generating taliks (unfrozen zones) within the permafrost that allow for hydrologic interactions between the surface water bodies and underlying aquifers and thus influence the hydrologic response of a landscape to climate change. Recent field studies and modeling exercises indicate that a fully coupled 2D or 3D Thermo-Hydraulic (TH) approach is required to understand and model past and future evolution such units (Kurylyk et al. 2014). However, there is presently a paucity of 3D numerical studies of permafrost thaw and associated hydrological changes, which can be partly attributed to the difficulty in verifying multi-dimensional results produced by numerical models. A benchmark exercise was initialized at the end of 2014. Participants convened from USA, Canada, Europe, representing 13 simulation codes. The benchmark exercises consist of several test cases inspired by existing literature (e.g. McKenzie et al., 2007) as well as new ones (Kurylyk et al. 2014; Grenier et al. in prep.; Rühaak et al. 2015). They range from simpler, purely thermal 1D cases to more complex, coupled 2D TH cases (benchmarks TH1, TH2, and TH3). Some experimental cases conducted in a cold room complement the validation approach. A web site hosted by LSCE (Laboratoire des Sciences du Climat et de l'Environnement) is an interaction platform for the participants and hosts the test case databases at the following address: https://wiki.lsce.ipsl.fr/interfrost. The results of the first stage of the benchmark exercise will be presented. We will mainly focus on the inter-comparison of participant results for the coupled cases TH2 & TH3. Both cases

  4. Precision intercomparison of beam current monitors at CEBAF

    SciTech Connect

    Kazimi, R.; Dunham, B.; Krafft, G.A.; Legg, r.; Liang, C.; Sinclair, C.; Mamosser, J.

    1995-12-31

    The CEBAF accelerator delivers a CW electron beam at fundamental 1497 MHz, with average beam current up to 200 {mu}A. Accurate, stable nonintercepting beam current monitors are required for: setup/control, monitoring of beam current and beam losses for machine protection and personnel safety, and providing beam current information to experimental users. Fundamental frequency stainless steel RF cavities have been chosen for these beam current monitors. This paper reports on precision intercomparison between two such RF cavities, an Unser monitor, and two Faraday cups, all located in the injector area. At the low beam energy in the injector, it is straightforward to verify the high efficiency of the Faraday cups, and the Unser monitor included a wire through it to permit an absolute calibration. The cavity intensity monitors have proven capable of stable, high precision monitoring of the beam current.

  5. International intercomparison for criticality dosimetry: the case of biological dosimetry.

    PubMed

    Roy, L; Buard, V; Delbos, M; Durand, V; Paillole, N; Grégoire, E; Voisin, P

    2004-01-01

    The Institute of Radiation Protection and Nuclear Safety (IRSN) organized a biological dosimetry international intercomparison with the purpose of comparing (i) dicentrics yield produced in human lymphocytes; (ii) the gamma and neutron dose estimate according to the corresponding laboratory calibration curve. The experimental reactor SILENE was used with different configurations: bare source 4 Gy, lead shield 1 and 2 Gy and a 60Co source 2 Gy. An increasing variation of dicentric yield per cell was observed between participants when there were more damages in the samples. Doses were derived from the observed dicentric rates according to the dose-effect relationship provided by each laboratory. Differences in dicentric rate values are more important than those in the corresponding dose values. The doses obtained by the participants were found to be in agreement with the given physical dose within 20%. The evaluation of the respective gamma and neutron dose was achieved only by four laboratories, with some small variations among them. PMID:15353693

  6. Intercomparison of cryogenic radiometers using silicon trap detectors

    NASA Astrophysics Data System (ADS)

    Lassila, A.; Hofer, H.; Ikonen, E.; Liedquist, L.; Stock, K. D.; Varpula, T.

    1997-02-01

    An intercomparison of cryogenic radiometers of HUT/VTT (Finland), PTB (Germany) and SP (Sweden) using silicon trap detectors was performed. Also results of monitoring of the responsivities of trap detectors over a 6 year period are presented. It was noticed that several non-idealities can undermine the agreement between results of calibrations. The non-uniformity of the responsivity of trap detectors made the results sensitive to alignment and beam size. The nonlinearity of some trap detectors was found to be large. The average relative differences in the results of the laboratories, when all known corrections are applied, are 0957-0233/8/2/003/img9 for HUT-PTB, 0957-0233/8/2/003/img10 for SP-PTB and 0957-0233/8/2/003/img11 for SP-HUT, with standard uncertainties of 0957-0233/8/2/003/img12 and 0957-0233/8/2/003/img13, respectively.

  7. Intercomparison of remote measurements of stratospheric NO and NO2

    NASA Astrophysics Data System (ADS)

    Roscoe, H. K.; Kerridge, B. J.; Pollitt, S.; Louisnard, N.; Flaud, J. M.

    1990-02-01

    During the 1982 and 1983 Balloon Intercomparison Campaigns, the vertical profile of stratospheric NO2 was measured remotely by nine instruments and that of NO by two. Total overhead columns were measured by two more instruments. Between 30 and 35 km, where measurements overlapped, agreement between NO profiles was within + or - 30 percent, which is better than the accuracies claimed by the experimenters. Between 35 and 40 km, there was similarly good agreement between NO2 profiles, but below 30 km, differences of greater than a factor of 3 were found. In the second campaign, NO2 values from most instruments agreed within their quoted errors, except that the Oxford radiometer gave much lower values; the first campaign and the column measurements show a more uniform spread of results.

  8. Abscess scan - radioactive

    MedlinePlus

    Radioactive abscess scan; Abscess scan; Indium Scan; Indium-labelled white blood cell scan ... the white blood cells are tagged with a radioactive substance called indium. The cells are then injected ...

  9. Radioactive iodine uptake

    MedlinePlus

    ... the testing center so that the amount of radioactivity in the thyroid gland can be measured. This ... The amount of radioactivity is very small, and there have been no documented side effects. The amount of iodine used is less than ...

  10. Radioactive diagnostic agent

    SciTech Connect

    Shigematsu, A.; Aihara, M.; Matsuda, M.; Suzuki, A.; Tsuya, A.

    1984-02-07

    A radioactive diagnostic agent for renal cortex, adrenal cortex, myocardium, brain stem, spinal nerve, etc., which comprises as an essential component monoiodoacetic acid wherein the iodine atom is radioactive.

  11. Exercise, Aging and Longevity.

    ERIC Educational Resources Information Center

    Brown, Stanley P.; Cundiff, David E.

    1988-01-01

    The question of whether or not a lifelong program of exercise actually has a bearing on longevity is discussed. The effects of exercise on the aging process, and the longevity-exercise relationship are reviewed. The conflicting evidence on the subject is presented. (JL)

  12. Japanese Radio Exercises. Revised.

    ERIC Educational Resources Information Center

    Young, Jocelyn

    This unit focuses on Japanese radio exercises which became popular in Japan just after World War II and are still used among students and workers in companies to help raise morale and form group unity. The exercises reflect the general role of exercise in Japanese culture--to serve as a symbol of unity and cooperation among the Japanese, as well…

  13. Stretch Band Exercise Program

    ERIC Educational Resources Information Center

    Skirka, Nicholas; Hume, Donald

    2007-01-01

    This article discusses how to use stretch bands for improving total body fitness and quality of life. A stretch band exercise program offers a versatile and inexpensive option to motivate participants to exercise. The authors suggest practical exercises that can be used in physical education to improve or maintain muscular strength and endurance,…

  14. Advanced resistive exercise device

    NASA Technical Reports Server (NTRS)

    Raboin, Jasen L. (Inventor); Niebuhr, Jason (Inventor); Cruz, Santana F. (Inventor); Lamoreaux, Christopher D. (Inventor)

    2008-01-01

    The present invention relates to an exercise device, which includes a vacuum cylinder and a flywheel. The flywheel provides an inertial component to the load, which is particularly well suited for use in space as it simulates exercising under normal gravity conditions. Also, the present invention relates to an exercise device, which has a vacuum cylinder and a load adjusting armbase assembly.

  15. Exercise and Your Heart.

    ERIC Educational Resources Information Center

    National Heart and Lung Inst. (DHHS/NIH), Bethesda, MD.

    This pamphlet presents information on the effects of physical activity on the heart and practical guidelines for starting and staying on an exercise program. The following topics are discussed: (1) the benefits of getting sufficient exercise; (2) possible risks in exercising compared to benefits; (3) when to seek doctor's advice and prevention of…

  16. Exercising in Cold Weather

    MedlinePlus

    ... www.nia.nih.gov/Go4Life Exercising in Cold Weather Exercise has benefits all year, even during winter. ... activities when it’s cold outside: l Check the weather forecast. If it’s very windy or cold, exercise ...

  17. Prenatal exercise research.

    PubMed

    Field, Tiffany

    2012-06-01

    In this review of recent research on prenatal exercise, studies from several different countries suggest that only approximately 40% of pregnant women exercise, even though about 92% are encouraged by their physicians to exercise, albeit with some 69% of the women being advised to limit their exercise. A moderate exercise regime reputedly increases infant birthweight to within the normal range, but only if exercise is decreased in late pregnancy. Lower intensity exercise such as water aerobics has decreased low back pain more than land-based physical exercise. Heart rate and blood pressure have been lower following yoga than walking, and complications like pregnancy-induced hypertension with associated intrauterine growth retardation and prematurity have been less frequent following yoga. No studies could be found on tai chi with pregnant women even though balance and the risk of falling are great concerns during pregnancy, and tai chi is one of the most effective forms of exercise for balance. Potential underlying mechanisms for exercise effects are that stimulating pressure receptors during exercise increases vagal activity which, in turn, decreases cortisol, increases serotonin and decreases substance P, leading to decreased pain. Decreased cortisol is particularly important inasmuch as cortisol negatively affects immune function and is a significant predictor of prematurity. Larger, more controlled trials are needed before recommendations can be made about the type and amount of pregnancy exercise. PMID:22721740

  18. Sleep, Exercise, and Nutrition.

    ERIC Educational Resources Information Center

    Harrelson, Orvis A.; And Others

    The first part of this booklet concerns why sleep and exercise are necessary. It includes a discussion of what occurs during sleep and what dreams are. It also deals with the benefits of exercise, fatigue, posture, and the correlation between exercise and personality. The second part concerns nutrition and the importance of food. This part covers…

  19. Intercomparison Calibration Study of Terra ASTER and MODIS

    NASA Astrophysics Data System (ADS)

    Yuan, K.; Thome, K. J.; McCorkel, J.

    2014-12-01

    Calibration and validation play an essential role during the acquisition and processing of satellite data for the Earth Observing System satellites in addition to being an integral part of maintaining scientific values of archived satellite data. The Advanced Spaceborne Thermal Emission and Reflection and Radiometer (ASTER) and Moderate Resolution Imaging Spectroradiometer (MODIS) are two of five sensors onboard the Terra platform - the Earth Observing System flagship. ASTER has a swath width of 60km with 8 bands in the visible and near infrared (VNIR) and thermal infrared (TIR) spectral range with a spatial resolution of 15m (bands 1-3) and 90m (bands 10-14), respectively while MODIS has a swath width of 2300km with 36 spectral bands from visible to infrared spectral range with a spatial resolution of 250m (bands 1-2), 500m (bands 3-7), and 1km (bands 8-36). ASTER is the 'zoom' lens and MODIS is the 'keystone' instrument for Terra; they provide quantitative measurements of various earth system variables to the scientific and to the broader community. The simultaneous view of the sensors simplifies the intercomparison between them and relies on the use of the Railroad Valley Playa test site to reduce uncertainties caused by spatial heterogeneity and spectral differences in the sensors. The fact that Railroad Valley Playa is a calibration test site for ASTER ensures that ASTER was tasked at a higher rate over this area providing more scenes for the intercomparison. The study compares ASTER L1B data for the three VNIR bands reprocessed with recent calibration updates and MODIS 02 Collection 6 data products for the similar bands. No correction for geometry angle is needed and coincident 3-km by 3-km regions are used to reduce the impact of spatial heterogeneity. A correction for spectral differences between the sensors is applied based on averages of ground measurements of the test site.

  20. Network for the Detection of Stratospheric Change (NDSC) FTIR Intercomparison at Table Mountain Facility, November 1996

    NASA Technical Reports Server (NTRS)

    Toon, G.; Goldman, A.; Walsh, C.; Bell, W.; Blavier, J. -F.; Sen, B.; Coffey, M.; Hannigan, J.; Mankin, W.

    2000-01-01

    An intercomparison of four Fourier Transform Infrared (FTIR) spectrometers, operated side by side by JPL, NCAR, and NPL groups, using two different spectral fitting algorithms, was conducted at JPL's Table Mountain Facility (TMF) during November 1996.

  1. INTERCOMPARISON STUDY OF ATMOSPHERIC MERCURY MODELS: 1. COMPARISON OF MODELS WITH SHORT-TERM MEASUREMENTS

    EPA Science Inventory

    Five regional scale models with a horizontal domain covering the European continent and its surrounding seas, one hemispheric and one global scale model participated in an atmospheric mercury modelling intercomparison study. Model-predicted concentrations in ambient air were comp...

  2. Statistical intercomparison of global climate models: A common principal component approach with application to GCM data

    SciTech Connect

    Sengupta, S.K.; Boyle, J.S.

    1993-05-01

    Variables describing atmospheric circulation and other climate parameters derived from various GCMs and obtained from observations can be represented on a spatio-temporal grid (lattice) structure. The primary objective of this paper is to explore existing as well as some new statistical methods to analyze such data structures for the purpose of model diagnostics and intercomparison from a statistical perspective. Among the several statistical methods considered here, a new method based on common principal components appears most promising for the purpose of intercomparison of spatio-temporal data structures arising in the task of model/model and model/data intercomparison. A complete strategy for such an intercomparison is outlined. The strategy includes two steps. First, the commonality of spatial structures in two (or more) fields is captured in the common principal vectors. Second, the corresponding principal components obtained as time series are then compared on the basis of similarities in their temporal evolution.

  3. Assessing radiation impact at a protected coastal sand dune site: an intercomparison of models for estimating the radiological exposure of non-human biota.

    PubMed

    Wood, Michael D; Beresford, Nicholas A; Barnett, Catherine L; Copplestone, David; Leah, Richard T

    2009-12-01

    This paper presents the application of three publicly available biota dose assessment models (the ERICA Tool, R&D128/SP1a and RESRAD-BIOTA) to an assessment of the Drigg coastal sand dunes. Using measured (90)Sr, (99)Tc, (137)Cs, (238)Pu, (239+240)Pu and (241)Am activity concentrations in sand dune soil, activity concentration and dose rate predictions are made for a range of organisms including amphibians, birds, invertebrates, mammals, reptiles, plants and fungi. Predicted biota activity concentrations are compared to measured data where available. The main source of variability in the model predictions is the transfer parameters used and it is concluded that developing the available transfer databases should be a focus of future research effort. The value of taking an informed user approach to investigate the way in which models may be expected to be applied in practice is highlighted and a strategy for the future development of intercomparison exercises is presented. PMID:19447531

  4. Intercomparison of three microwave/infrared high resolution line-by-line radiative transfer codes

    NASA Astrophysics Data System (ADS)

    Schreier, F.; Garcia, S. Gimeno; Milz, M.; Kottayil, A.; Höpfner, M.; von Clarmann, T.; Stiller, G.

    2013-05-01

    An intercomparison of three line-by-line (lbl) codes developed independently for atmospheric sounding - ARTS, GARLIC, and KOPRA - has been performed for a thermal infrared nadir sounding application assuming a HIRS-like (High resolution Infrared Radiation Sounder) setup. Radiances for the HIRS infrared channels and a set of 42 atmospheric profiles from the "Garand dataset" have been computed. Results of this intercomparison and a discussion of reasons of the observed differences are presented.

  5. Airborne sulfur trace species intercomparison campaign: Sulfur dioxide, dimethylsulfide, hydrogen sulfide, carbon disulfide, and carbonyl sulfide

    NASA Technical Reports Server (NTRS)

    Gregory, Gerald L.; Hoell, James M., Jr.; Davis, Douglas D.

    1991-01-01

    Results from an airborne intercomparison of techniques to measure tropospheric levels of sulfur trace gases are presented. The intercomparison was part of the NASA Global Tropospheric Experiment (GTE) and was conducted during the summer of 1989. The intercomparisons were conducted on the Wallops Electra aircraft during flights from Wallops Island, Virginia, and Natal, Brazil. Sulfur measurements intercompared included sulfur dioxide (SO2), dimethylsulfide (DMS), hydrogen sulfide (H2S), carbon disulfide (CS2), and carbonyl sulfide (OCS). Measurement techniques ranged from filter collection systems with post-flight analyses to mass spectrometer and gas chromatograph systems employing various methods for measuring and identifying the sulfur gases during flight. Sampling schedules for the techniques ranged from integrated collections over periods as long as 50 minutes to one- to three-minute samples every ten or fifteen minutes. Several of the techniques provided measurements of more than one sulfur gas. Instruments employing different detection principles were involved in each of the sulfur intercomparisons. Also included in the intercomparison measurement scenario were a host of supporting measurements (i.e., ozone, nitrogen oxides, carbon monoxide, total sulfur, aerosols, etc.) for purposes of: (1) interpreting results (i.e., correlation of any noted instrument disagreement with the chemical composition of the measurement environment); and (2) providing supporting chemical data to meet CITE-3 science objectives of studying ozone/sulfur photochemistry, diurnal cycles, etc. The results of the intercomparison study are briefly discussed.

  6. Intercomparison of HONO Measurements Made Using Wet-Chemical (NITROMAC) and Spectroscopic (IBBCEAS & LP/FAGE) Techniques

    NASA Astrophysics Data System (ADS)

    Dusanter, S.; Lew, M.; Bottorff, B.; Bechara, J.; Mielke, L. H.; Berke, A.; Raff, J. D.; Stevens, P. S.; Afif, C.

    2013-12-01

    A good understanding of the oxidative capacity of the atmosphere is important to tackle fundamental issues related to climate change and air quality. The hydroxyl radical (OH) is the dominant oxidant in the daytime troposphere and an accurate description of its sources in atmospheric models is of utmost importance. Recent field studies indicate higher-than-expected concentrations of HONO during the daytime, suggesting that the photolysis of HONO may be an important underestimated source of OH. Understanding the tropospheric HONO budget requires confidence in analytical instrumentation capable of selectively measuring HONO. In this presentation, we discuss an intercomparison study of HONO measurements performed during summer 2013 at the edge of a hardwood forest in Southern Indiana. This exercise involved a wet chemical technique (NITROMAC), an Incoherent Broad-Band Cavity Enhanced Absorption Spectroscopy instrument (IBBCEAS), and a Laser-Photofragmentation/Fluorescence Assay by Gas Expansion instrument (LP/FAGE). The agreement observed between the three techniques will be discussed for both ambient measurements and cross calibration experiments.

  7. Intercomparison of mid latitude storm diagnostics (IMILAST) - project update

    NASA Astrophysics Data System (ADS)

    Neu, Urs

    2015-04-01

    The analysis of the occurrence of mid-latitude storms is of great socio-economical interest due to their vast and destructive impacts. However, a unique definition of cyclones is missing, and therefore the definition of what a cyclone is as well as quantifying its strength contains subjective choices. Existing automatic cyclone identification and tracking algorithms are based on different definitions and use diverse characteristics. These methods generally differ in the following aspects: data transformation (e.g., grid transformation, smoothing, etc.), metrics used for cyclone identification (e.g. sea level pressure or vorticity), cyclone identification procedures, different tracking methods (e.g. near neighborhood search), and elimination criteria (e.g., requiring a certain pressure minimum or minimum life time). The different choices made in these algorithms can lead to substantial differences in cyclone climatologies, temporal trends of the frequency, strength, or other characteristics of cyclones. The project IMILAST systematically compares different cyclone detection and tracking methods (currently 15 different algorithms), with the aim to comprehensively assess systematic uncertainties in mid-latitudinal storm identification and tracking. IMILAST uses the ERA-interim reanalysis data set as a common data basis in all studies. The first two intercomparison experiments focused on differences between the methods with respect to number, track density, life cycle characteristics, and trend patterns on the one hand and potential differences of the long-term climate change signal of cyclonic activity between the methods on the other hand. For current analysis activities, the intercomparison period is extended to a 30 year period from 1979 to 2009 and focuses on more specific aspects, such as parameter sensitivities, the comparison of automated to manual tracking sets, regional analysis (regional trends, Arctic and Antarctic cyclones, cyclones in the Mediterranean

  8. Intercomparison of stratospheric gravity wave observations with AIRS and IASI

    NASA Astrophysics Data System (ADS)

    Hoffmann, Lars; Alexander, M. Joan; Clerbaux, Cathy; Grimsdell, Alison W.; Meyer, Catrin I.; Rößler, Thomas; Tournier, Bernard

    2015-04-01

    Gravity waves are an important driver for the atmospheric circulation and have substantial impact on weather and climate. Satellite instruments offer excellent opportunities to study gravity waves on a global scale. This study focuses on observations from the Atmospheric Infrared Sounder (AIRS) onboard the National Aeronautics and Space Administration's Aqua satellite and the Infrared Atmospheric Sounding Interferometer (IASI) onboard the European MetOp satellites. The main aim of this study is an intercomparison of stratospheric gravity wave observations of both instruments. In particular, we analyzed AIRS and IASI 4.3 μm brightness temperature measurements, which directly relate to stratospheric temperature. Three case studies showed that AIRS and IASI provide a clear and consistent picture of the temporal development of individual gravity wave events. Statistical comparisons based on a five-year period of measurements (2008 - 2012) showed similar spatial and temporal patterns of gravity wave activity. However, the statistical comparisons also revealed systematic differences of variances between AIRS and IASI that we attribute to the different spatial measurement characteristics of both instruments. We also found differences between day- and nighttime data that are partly due to the local time variations of the gravity wave sources. While AIRS has been used successfully in many previous gravity wave studies, IASI data are applied here for the first time for that purpose. Our study shows that gravity wave observations from different hyperspectral infrared sounders such as AIRS and IASI can be directly related to each other, if instrument-specific characteristics such as different noise levels and spatial resolution and sampling are carefully considered. The ability to combine observations from different satellites provides an opportunity to create a long-term record, which is an exciting prospect for future climatological studies of stratospheric gravity wave

  9. Overview of the Coupled Model Intercomparison Project (CMIP)

    SciTech Connect

    Meehl, G A; Covey, C; McAvaney, B; Latif, M; Stouffer, R J

    2004-08-05

    The Coupled Model Intercomparison Project (CMIP) is designed to allow study and intercomparison of multi-model simulations of present-day and future climate. The latter are represented by idealized forcing of compounded 1% per year CO2 increase to the time of CO2 doubling near year 70 in simulations with global coupled models that contain, typically, components representing atmosphere, ocean, sea ice and land surface. Results from CMIP diagnostic subprojects were presented at the Second CMIP Workshop held at the Max Planck Institute for Meteorology in Hamburg, Germany, in September, 2003. Significant progress in diagnosing and understanding results from global coupled models has been made since the First CMIP Workshop in Melbourne, Australia in 1998. For example, the issue of flux adjustment is slowly fading as more and more models obtain stable multi-century surface climates without them. El Nino variability, usually about half the observed amplitude in the previous generation of coupled models, is now more accurately simulated in the present generation of global coupled models, though there are still biases in simulating the patterns of maximum variability. Typical resolutions of atmospheric component models contained in coupled models is now usually around 2.5 degrees latitude-longitude, with the ocean components often having about twice the atmospheric model resolution, with even higher resolution in the equatorial tropics. Some new-generation coupled models have atmospheric model resolutions of around 1.5 degrees latitude-longitude. Modeling groups now routinely run the CMIP control and 1% CO2 simulations in addition to 20th and 21st century climate simulations with a variety of forcings (e.g. volcanoes, solar variability, anthropogenic sulfate aerosols, ozone, and greenhouse gases (GHGs), with the anthropogenic forcings for future climate as well). However, persistent systematic errors noted in previous generations of global coupled models still are present

  10. Aging, exercise, and attention.

    PubMed

    Hawkins, H L; Kramer, A F; Capaldi, D

    1992-12-01

    The authors investigated the relationship among aging, attentional processes, and exercise in 2 experiments. First they examined age differences on 2 attentional tasks, a time-sharing task and an attentional flexibility task. Young adults alternated attention between 2 sequenced tasks more rapidly and time-shared the processing of 2 tasks more efficiently than older adults. They then investigated the effects of aerobic exercise on the same 2 attentional tasks in older adults. Following the 10-week exercise program, older exercisers showed substantially more improvement in alternation speed and time-sharing efficiency than older controls. Interestingly, this exercise effect was specific to dual-task processing. Both groups of subjects showed equivalent effects on single-task performance. These results indicate that aerobic exercise can exert a beneficial influence on the efficiency of at least 2 different attentional processes in older adults. PMID:1466833