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Sample records for calibrations intercomparison program

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

    International Nuclear Information System (INIS)

    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

  2. DOE radiological calibrations intercomparison program: Results of fiscal year 1986

    International Nuclear Information System (INIS)

    Cummings, F.M.; Roberson, P.L.; McDonald, J.C.

    1987-05-01

    The Department of Energy Radiological Calibration Intercomparison Program was initiated in January 1986, under the research portion of the DOE Laboratory Accreditation Program. The program operates via the exchange of transfer standards, consisting of instrument sets and standard secondary beta sources. There are two instrument sets and the scheduled use has been staggered such that one set is available for use during each month. One set of secondary standard beta sources is available for use bimonthly. During the 1986 fiscal year, five laboratories used the instrument sets and three laboratories used the beta source set. Results were reported for all the measurements. The average and one standard deviation of the ratios of participant results to Pacific Northwest Laboratory calibration values were 1.12 +- 0.17 for gamma measurements. Those ratios for the gamma measurements varied from 0.98 to 3.06. The larger differences of results from measurements performed at two facilities were directly attributable to unfamiliarity with the intercomparison instruments. The average and one standard deviation of the ratios of participant results to PNL calibration values obtained using the secondary 90 Sr beta source was 1.02 +- 0.05, which is well within measurement uncertainties. The one participant who performed measurements using 147 Pm and 204 Tl sources obtained ratios of 0.68 and 1.11, respectively. No measurements were performed using neutron or x-ray sources

  3. ABACC's laboratory intercomparison program

    International Nuclear Information System (INIS)

    Almeida, Gevaldo L. de; Esteban, Adolfo; Almeida, Silvio G. de; Araujo, Radier M. de; Rocha, Zildete

    1996-01-01

    A Laboratory Intercomparison Program involving Brazilian and Argentine laboratories, with the special participation of New Brunswick Laboratory - DOE and IAEA Seibersdorf Safeguards Laboratory, was implanted by ABACC having as main purpose to qualify a network to provide analytical services to this Agency on its role as administrator of the Common System of Accountability and Control of Nuclear Materials. For the first round robin of this Program, 15 laboratories were invited to perform elemental analysis on UO 2 samples, by using any desired method. Thirteen confirmed the participation and 10 reported the results. After an evaluation of the results by using a Two-Way Variance Analysis applied to a nested error model, it was found that 5 of them deviate less than 0.1% from the reference value established for the UO 2 uranium contents, being thus situated within the limits adopted for the target values, while the remaining ones reach a maximal deviation of 0.44%. The outcome of this evaluation, was sent to the laboratories, providing them with a feedback to improve their performance by applying corrective actions to the detected sources of errors or bias related to the methods techniques and procedures. (author)

  4. Environmental radioactive intercomparison program and radioactive standards program

    Energy Technology Data Exchange (ETDEWEB)

    Dilbeck, G. [Environmental Monitoring Systems Laboratory, Las Vegas, NV (United States)

    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.

  5. Intercomparison and calibration of dose calibrators used in nuclear medicine facilities

    CERN Document Server

    Costa, A M D

    2003-01-01

    The aim of this work was to establish a working standard for intercomparison and calibration of dose calibrators used in most of nuclear medicine facilities for the determination of the activity of radionuclides administered to patients in specific examinations or therapeutic procedures. A commercial dose calibrator, a set of standard radioactive sources, and syringes, vials and ampoules with radionuclide solutions used in nuclear medicine were utilized in this work. The commercial dose calibrator was calibrated for radionuclide solutions used in nuclear medicine. Simple instrument tests, such as linearity response and variation response with the source volume at a constant source activity concentration were performed. This instrument may be used as a reference system for intercomparison and calibration of other activity meters, as a method of quality control of dose calibrators utilized in nuclear medicine facilities.

  6. Calibration and intercomparison of neutron moderation spectrometers

    International Nuclear Information System (INIS)

    Rimpler, A.; Hermanska, J.; Prouza, Z.

    1989-01-01

    Results have been reported of comparative measurements of neutron fields from bare PuBe and Cf sources using multisphere (Bonner) spectrometers. The experiments were carried out by the Institute of Biophysics and Nuclear Medicine at Charles University in Prague and the National Board for Atomic Safety and Radiation Protection in Berlin. Both sides agreed upon uniform measuring conditions and calibration factors thus rendering possible the comparability of the dosimetric parameters which have been determined and verified, respectively, to an accuracy of ± 10%. 20 refs., 10 tabs., 2 figs. (author)

  7. First intercomparison exercise in the frame of the coordinated investigation program of the IAEA on regional intercomparison of personal dosimetry

    International Nuclear Information System (INIS)

    Massera, G.; Papadopulos, S.B.; Gregori, B.N.; DaSilva, T.; Griffith, R.; )

    1998-01-01

    During the days 7 and 11 of October of 1996 took place in Buenos Aires, Argentina, the first Meeting of the Coordinated Investigation program of the IAEA on Regional Intercomparison of Personal Dosimetry for Latin American. In this meeting participated nine representatives of reference laboratories and of personal dosimetry of the region. Fundamental aspect of personal dosimetry relates with the quantity personal dose equivalent Hp application and the implementation of intercomparison exercise in order to improve the quality of the dose estimation have been discussed. Also lectures carried out by the specialist on Hp and practical aspects of it implementation; answer and calibration according to the ISO 4037; intercomparison methods: procedures and organizations. It was carried out the first intercomparison exercise where the participants collaborated in the preparations and irradiations of personal dosemeters they have brought. (author)

  8. Calibration and intercomparison methods of dose calibrators used in nuclear medicine facilities

    International Nuclear Information System (INIS)

    Costa, Alessandro Martins da

    1999-01-01

    Dose calibrators are used in most of the nuclear medicine facilities to determine the amount of radioactivity administered to a patient in a particular investigation or therapeutic procedure. It is therefore of vital importance that the equipment used presents good performance and is regular;y calibrated at a authorized laboratory. This occurs of adequate quality assurance procedures are carried out. Such quality control tests should be performed daily, other biannually or yearly, testing, for example, its accuracy and precision, the reproducibility and response linearity. In this work a commercial dose calibrator was calibrated with solution of radionuclides used in nuclear medicine. Simple instrument tests, such as response linearity and the response variation of the source volume increase at a constant source activity concentration, were performed. This instrument can now be used as a working standard for calibration of other dose calibrators/ An intercomparison procedure was proposed as a method of quality control of dose calibrators used in nuclear medicine facilities. (author)

  9. IAEA/SSDL intercomparison of calibration factors for therapy level ionization chambers

    International Nuclear Information System (INIS)

    Lu Jilong; Cheng Jinsheng; Guo Zhaohui; Li Kaibao

    2005-01-01

    Objective: By participating in IAEA-SSDL intercomparison, a dose to water calibration factor was introduced in order to check the measuring accuracy of 60 Co radiotherapy dose level standard and ensure the reliability and consistency of our calibration. Methods: The authors carried out both air kerma and absorbed dose to water calibrations against 60 Co γ-rays for one of our field class ionization chambers, and sent the results together with the chamber to IAEA dosimetry laboratory for calibration, then IAEA calibrated it and gave the deviation of the intercomparison. Results: The deviation of our air kerma calibration factors is -0.5%, and the deviation of our absorbed dose to water calibration factors is 0.4%. Conclusion: The deviation of calibration factors between IAEA and SSDL should be no more than ±1.5%. Therefore, the result of this intercomparison is considered satisfactory. (authors)

  10. Performance of dichromate dosimetry systems in calibration and dose intercomparison

    International Nuclear Information System (INIS)

    Bof, E.S.; Smolko, E.

    1999-01-01

    This report presents the results of the High Dose Dosimetry Laboratory of Argentina during ten years of international intercomparisons for high dose with the International Dose Assurance Service (IDAS) of the IAEA, using the standard high dose dichromate dosimetry system, and the results of a high dose intercomparison regional exercise in which our Laboratory acted as a reference laboratory, using the standard high dose and low dose dichromate dosimetry system. (author)

  11. Radiocarbon intercomparison program for Chauvet Cave

    International Nuclear Information System (INIS)

    Cuzange, M.T.; Delque-Kolic, E.; Oberlin, C.; Goslar, T.; Grootes, P.M.; Nadeau, M.J.; Higham, T.; Ramsey, C.B.; Kaltnecker, E.; Paterne, M.; Valladas, H.; Van der Plicht, J.; Van der Plicht, J.; Clottes, J.; Geneste, J.M.

    2007-01-01

    We present the first results of an accelerator mass spectrometry (AMS) radiocarbon intercomparison program on 3 different charcoal samples collected in one of the hearths of the Megaceros gallery of Chauvet Cave (Ardeche, France). This cave, rich in parietal decoration, is important for the study of the appearance and evolution of prehistoric art because certain drawings have been 14 C dated to the Aurignacian period at the beginning of the Upper Paleolithic. The new dates indicate an age of about 32,000 BP, which is consistent with this attribution and in agreement with the results from the same sector of the cave measured previously at the Laboratoire des Sciences du Climat et de l'Environnement (LSCE). Six laboratories were involved in the intercomparison. Samples were measured in 4 AMS facilities: Center for Isotope Research, Groningen University, the Netherlands; the Oxford Radiocarbon Accelerator Unit, UK; the Centre de datation par le carbone 14, Univ. Claude Bernard Lyon 1, France (measured by AMS facilities of Poznan University, Poland); and the LSCE, UMR CEA-CNRS-UVSQ, France (measured by the Leibniz-Labor of Christian-Albrechts-Universitat Kiel, Germany). (authors)

  12. Intercomparison programs - a tool for the implementation of a quality assurance program in bioassay

    International Nuclear Information System (INIS)

    Mesquita, Sueli A. de; Sousa, Wanderson O.; Juliao, Ligia M.Q.C.; Santos, Maristela S.; Fernandes, Paulo C.P.

    2009-01-01

    In vitro bioassay laboratories need to have means to demonstrate that they are technically competent, operate an effective quality system, and are able to generate technically valid calibration and test results. The reliability of the results of measurements has a high influence on the reliability of the dose assessment. Inter-laboratory tests are one of the tools for assessing the analytical consistency of in vitro bioassay laboratories. The intercomparison exercises provide an opportunity to compare radiochemistry techniques for in vitro analysis of biological samples. The in vitro Laboratory of the Instituto de Radioprotecao e Dosimetria has therefore participated in the intercomparison exercises sponsored by PROCORAD, ARCAL and IAEA since 1998. The intercomparison exercises comprise measurements of gamma and beta emitters in urine samples and alpha emitters in urine and faecal samples. This paper presents the performance of the IRD in vitro bioassay laboratory in the past intercomparisons. The results demonstrate that in vitro laboratory is able to generate technically valid results, which also guarantee the support for a quality assurance program and accreditation by competent organism in Brazil. (author)

  13. NVLAP calibration laboratory program

    Energy Technology Data Exchange (ETDEWEB)

    Cigler, J.L.

    1993-12-31

    This paper presents an overview of the progress up to April 1993 in the development of the Calibration Laboratories Accreditation Program within the framework of the National Voluntary Laboratory Accreditation Program (NVLAP) at the National Institute of Standards and Technology (NIST).

  14. NVLAP calibration laboratory program

    International Nuclear Information System (INIS)

    Cigler, J.L.

    1993-01-01

    This paper presents an overview of the progress up to April 1993 in the development of the Calibration Laboratories Accreditation Program within the framework of the National Voluntary Laboratory Accreditation Program (NVLAP) at the National Institute of Standards and Technology (NIST)

  15. Results of the PEP`93 intercomparison of reference cell calibrations and newer technology performance measurements

    Energy Technology Data Exchange (ETDEWEB)

    Osterwald, C.R.; Emery, K. [National Renewable Energy Lab., Golden, CO (United States); Anevsky, S. [All-Union Research Inst. for Optophysical Measurements, Moscow (Russian Federation)] [and others

    1996-05-01

    This paper presents the results of an international intercomparison of photovoltaic (PV) performance measurements and calibrations. The intercomparison, which was organized and operated by a group of experts representing national laboratories from across the globe (i.e., the authors of this paper), was accomplished by circulating two sample sets. One set consisted of twenty silicon reference cells that would, hopefully, form the basis of an international PV reference scale. A qualification procedure applied to the calibration results gave average calibration numbers with an overall standard deviation of less than 2% for the entire set. The second set was assembled from a wide range of newer technologies that present unique problems for PV measurements. As might be expected, these results showed much larger differences among laboratories. Methods were then identified that should be used to measure such devices, along with problems to avoid.

  16. Improvements in world-wide intercomparison of PV module calibration

    OpenAIRE

    Salis, E.; Pavanello, D.; Field, M.; Kräling, U.; Neuberger, F.; Kiefer, K.; Osterwald, C.; Rummel, S.; Levi, D.; Hishikawa, Y.; Yamagoe, K.; Ohshima, H.; Yoshita, M.; Müllejans, H.

    2017-01-01

    The calibration of the electrical performance for seven photovoltaic (PV) modules was compared between four reference laboratories on three continents. The devices included two samples in standard and two in high-efficiency crystalline silicon technology, two CI(G)S and one CdTe module. The reference value for each PV module parameter was calculated from the average of the results of all four laboratories, weighted by the respective measurement uncertainties. All single results were then anal...

  17. Airborne hygrometer calibration inter-comparison against a metrological water vapour standard

    Science.gov (United States)

    Smorgon, Denis; Boese, Norbert; Ebert, Volker

    2014-05-01

    Water vapour is the most important atmospheric greenhouse gas, which causes a major feedback to warming and other changes in the climate system. Knowledge of the distribution of water vapour and its climate induced changes is especially important in the upper troposphere and lower stratosphere (UT/LS) where vapour plays a critical role in atmospheric radiative balance, cirrus cloud formation, and photochemistry. But, our understanding of water in the UT/LS is limited by significant uncertainties in current UT/LS water measurements. One of the most comprehensive inter-comparison campaigns for airborne hygrometers, termed AQUAVIT (AV1) [1], took place in 2007 at the AIDA chamber at the Karlsruhe Institute of Technology (KIT) in Germany. AV1 was a well-defined, referred, blind inter-comparison of 22 airborne field instruments from 17 international research groups. One major metrological deficit of AV1, however, was, that no traceable reference instrument participated in the inter-comparison experiments and that the calibration procedures of the participating instruments were not monitored or interrogated. Consequently a follow-up inter-comparison was organized in April 2013, which for the first time also provides a traceable link to the international humidity scale. This AQUAVIT2 (AV2) campaign (details see: http://www.imk-aaf.kit.edu/aquavit/index.php/Main_Page) was again located at KIT/AIDA and organised by an international organizing committee including KIT, PTB, FZJ and others. Generally AV2 is divided in two parallel comparisons: 1) AV2-A uses the AIDA chamber for a simultaneous comparison of all instruments (incl. sampling and in-situ instruments) over a broad range of conditions characteristic for the UT/LS; 2) AV2-B, about which this paper is reporting, is a sequential comparison of selected hygrometers and (when possible) their reference calibration infrastructures by means of a chilled mirror hygrometer traced back to the primary National humidity standard

  18. The program of international intercomparison of accident dosimetry

    International Nuclear Information System (INIS)

    2002-06-01

    The French institute of radioprotection and nuclear safety (IRSN) has carried out in June 2002 an international intercomparison program for the testing of the physical and biological accident dosimetry techniques. The intercomparison is jointly organized by the IRSN and the OECD-NEA with the sustain of the European commission and the collaboration of the CEA centre of Valduc (France). About 30 countries have participated to this program. Each country has supplied its own dosimeters and biological samples which have been irradiated using the Silene reactor of CEA-Valduc or a 60 Co source. These experiments allow to test the new dosimetric techniques that have been developed since the previous intercomparison program (1993) and to confirm or improve the performances of older techniques. Aside from the intercomparison exercise, this report makes a status of the known radiological accidents and of the effects of high doses of ionizing radiations on human health (symptoms, therapeutics). It explains the phenomenology of criticality accidents, the prevention means, and the history of such accidents up to the Tokai-Mura one in 1999. Finally, the dosimetry of criticality is presented with its physical and biological techniques. (J.S.)

  19. ENDFIC - A program for indexing and intercomparison of ENDFs

    International Nuclear Information System (INIS)

    Gopalakrishnan, V.; Devan, K.

    1995-01-01

    The program ENDFIC, a nuclear data utility program in FORTRAN, was written under contract on 'Indexing and Intercomparison Programme of Evaluated Nuclear Data Files' (No. 7866/RB/TC), between Indira Gandhi Centre for Atomic Research, Kalpakkam, and the International Atomic Energy Agency, Vienna. The program can be used for the following two activities: i. INFO activity: to find from a given ENDF/B formatted evaluated nuclear data library, information regarding the contents of the library; ii. COMP activity: to do comparison of cross sections from several given ENDF libraries. 1 ref

  20. Intercomparison of the air kerma and absorbed dose to water therapy calibrations provided by NRPA and CPRH SSDLs

    International Nuclear Information System (INIS)

    Morales, J.A.; Campa, R.; Bjerke, H.; Jensen, H.

    2001-01-01

    The primary goal of any calibration laboratory is to routinely provide calibration services of the highest accuracy. To this end, the laboratory should be equipped with measuring standards of the highest metrological quality traceable to the international measuring system, should establish the appropriate calibration conditions and implement good measuring and working practices. In the case of the Secondary Standard Dosimetry Laboratory (SSDL) members of the IAEA/WHO Network of SSDLs, a great deal of the service quality relies on the appropriate laboratory design and implementation of the recommended calibration practices. Different approaches have been used by SSDLs to guarantee the traceability of the reference standard to the international measurement system. These include calibration of their standards at the IAEA Dosimetry Laboratory, direct calibration at a primary standards laboratory or at a national calibration laboratory. The stability of reference and working standards is usually checked by means of radioactive check source measurements. The most comprehensive way that a laboratory could test its overall measurement competence is by taking part in comparisons with other laboratories of the same or higher metrological level. Regular efforts have been done at the regional scale by organizing such intercomparison exercises where the evaluation of the accuracy of secondary standards or the validation of new calibration methods has been the main objectives. Perhaps, the most important contribution to the assessment of SSDLs quality has been the periodical external measurement audit provided by the IAEA during the last years. Mos of these efforts have, however, only been focused on in-air and recently in-water calibration at the 60 Co radiation quality. An intercomparison of the therapy calibration services available at the SSDLs of the Norwegian Radiation Protection Authority (NRPA) and of the Center for Radiation Protection and Hygiene (CPHR) was organized

  1. Intercomparison of calibration procedures of high dose rate 192 Ir sources in Brazil and a proposal of a new methodology

    International Nuclear Information System (INIS)

    Marechal, M.H.; Almeida, C.E. de

    1998-01-01

    The objective of this paper is to report the results of an intercomparison of the calibration procedures for 192 Ir sources presently in use in Brazil and to proposal a calibration procedure to derive the N k for a Farmer type ionization chamber for 192 Ir energy by interpolating from a 60 Co gamma-rays and 250 kV x-rays calibration factors. the intercomparison results were all within ± 3.0 % except one case where 4.6 % was observed and latter identified as a problem with N-k value for X-rays. The method proposed by the present work make possible the improvement of the metrological coherence among the calibration laboratories and their users once the N k values could then provided by any of the members of SSDL network. (Author)

  2. Calibration and intercomparison methods of dose calibrators used in nuclear medicine facilities; Metodos de calibracao e de intercomparacao de calibradores de dose utilizados em servicos de medicina nuclear

    Energy Technology Data Exchange (ETDEWEB)

    Costa, Alessandro Martins da

    1999-07-01

    Dose calibrators are used in most of the nuclear medicine facilities to determine the amount of radioactivity administered to a patient in a particular investigation or therapeutic procedure. It is therefore of vital importance that the equipment used presents good performance and is regular;y calibrated at a authorized laboratory. This occurs of adequate quality assurance procedures are carried out. Such quality control tests should be performed daily, other biannually or yearly, testing, for example, its accuracy and precision, the reproducibility and response linearity. In this work a commercial dose calibrator was calibrated with solution of radionuclides used in nuclear medicine. Simple instrument tests, such as response linearity and the response variation of the source volume increase at a constant source activity concentration, were performed. This instrument can now be used as a working standard for calibration of other dose calibrators/ An intercomparison procedure was proposed as a method of quality control of dose calibrators used in nuclear medicine facilities. (author)

  3. Second radiocarbon intercomparison program for the Chauvet-Pont d'Arc cave, Ardeche, France

    International Nuclear Information System (INIS)

    Quiles, A.; Valladas, H.; Kaltnecker, E.; Geneste, J.M.; Clottes, J.; Berthier, B.; Delque-Kolic, E.; Dumoulin, J.P.

    2014-01-01

    The Chauvet-Pont d'Arc Cave is one of the most important sites for the study of the earliest manifestations and development of prehistoric art at the beginning of the Upper Paleolithic. Different dating techniques have been performed thus far (AMS 14 C, U/Th TIMS, 36 Cl dating) to model the chronological framework of this decorated cave. The cave yielded several large charcoal fragments, which enabled the opportunity for obtaining multiple dates; thus, a First Radiocarbon Intercomparison Program (FIP) was initiated in 2004 using three charcoal pieces. The FIP demonstrated that those cross-dated samples belonged to a time period associated with the first human occupation. One of the statistical interests of an intercomparison program is to reduce the uncertainty on the sample age; thus, to further assess the accuracy of the chronological framework, the Second Intercomparison Program (SIP) involving 10 international 14 C laboratories was carried out on two pieces of charcoal found inside two hearth structures of the Galerie des Megaceros. Each laboratory used its own pretreatment and AMS facilities. In total, 21 and 22 measurements were performed, respectively, which yielded consistent results averaging ∼32 ka BP. Two strategies have currently been developed to identify statistical outliers and to deal with them; both lead to quasi-identical calibrated combined densities. Finally, the new results were compared with those of the FIP, leading to the important conclusion that five different samples from at least three different hearth structures give really tightened temporal densities, associated with one short human occupation in the Galerie des Megaceros. (authors)

  4. Report of the Intercomparison program by thermoluminescent dosimetry for Secondary Standard Dosimetry Laboratories

    International Nuclear Information System (INIS)

    Papadopulos, Susana

    2000-01-01

    In this report the results of an intercomparison program within a research coordinated program are presented. This is a third phase of the study that consisted in to evaluate the implementation of the new ICRU quantities for individual monitoring by the SSDLs, their capabilities to perform irradiations in different angles and the interpretation of the standard ISO 4370-3. This phase as well the first one was coordinated by Argentina through the Autoridad Regulatoria Nuclear that verified the performance of the participant laboratories. The SSDL of Argentina calibrated the dosimetric system to be used, and sent a set of tld dosimeters for irradiation at the SSDL or dosimetry laboratories of nine countries of latin america

  5. Participation of the Laboratorio de Radiotoxicologia of IPEN, SP, Brazil, in laboratory inter-comparison programs

    International Nuclear Information System (INIS)

    Mesquita, Sueli Alexandra de; Carneiro, Janete Cristina G.

    2005-01-01

    The Radiotoxicology Laboratory (LRT) of IPEN/CNEN-SP has as mission to assess internal internal contamination from individuals through qualitative and quantitative analysis of radionuclides present in biological samples. The LRT is able to meet the demand for in vitro monitoring and radiological and nuclear emergencies, both in the case of occupational exposures, as individuals. With the purpose of increasing the reliability of the test results, and keeping it up to date on new analytical techniques, the LRT participates annually in two laboratory inter-comparison programs: a national, the PNI (Programa Nacional de Intercomparacao), promoted by IRD/CNEN and an international from PROCORAD (Association for the Promotion of Quality Controls in Radiotoxicological Bioassay). The present work shows the performance of the LRT by means of the results obtained in the exercises for the quantification of natural uranium and uranium isotopes, promoted by both the inter-comparison programs in the year of 2004. The analysis of the obtained results demonstrates the good performance achieved by LRT, and confirms the sustainability of its quality system, required in calibration and testing laboratories

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

    International Nuclear Information System (INIS)

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

    2014-01-01

    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 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 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 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 99m Tc between Nuclear Medicine centers without source transfer and can easily be adapted to other short half-life radionuclides

  7. BRDF Characterization and Calibration Inter-Comparison between Terra MODIS, Aqua MODIS, and S-NPP VIIRS

    Science.gov (United States)

    Chang, Tiejun; Xiong, Xiaoxiong (Jack); Angal, Amit; Wu, Aisheng

    2016-01-01

    The inter-comparison of reflective solar bands (RSB) between Terra MODIS, Aqua MODIS, and SNPP VIIRS is very important for assessment of each instrument's calibration and to identify calibration improvements. One of the limitations of using their ground observations for the assessment is a lack of the simultaneous nadir overpasses (SNOs) over selected pseudo-invariant targets. In addition, their measurements over a selected Earth view target have significant difference in solar and view angles, and these differences magnify the effects of Bidirectional Reflectance Distribution Function (BRDF). In this work, an inter-comparison technique using a semi-empirical BRDF model is developed for reflectance correction. BRDF characterization requires a broad coverage of solar and view angles in the measurements over selected pseudo-invariant targets. Reflectance measurements over Libya 1, 2, and 4 desert sites from both the Aqua and Terra MODIS are regressed to a BRDF model with an adjustable coefficient accounting for the calibration difference between the two instruments. The BRDF coefficients for three desert sites for MODIS bands 1 to 9 are derived and the wavelength dependencies are presented. The analysis and inter-comparison are for MODIS bands 1 to 9 and VIIRS moderate resolution radiometric bands (M bands) M1, M2, M4, M5, M7, M8, M10 and imaging bands (I bands) I1-I3. Results show that the ratios from different sites are in good agreement. The ratios between Terra and Aqua MODIS from year 2003 to 2014 are presented. The inter-comparison between MODIS and VIIRS are analyzed for year 2014.

  8. The Canadian National Calibration Reference Center for Bioassay and in-vivo Monitoring: A program summary

    International Nuclear Information System (INIS)

    Kramer, G.H.; Zamora, M.L.

    1994-01-01

    The Canadian National Calibration Reference Center for Bioassay and in-vivo Monitoring is part of the Radiation Protection Bureau, Department of Health. The Reference Center operates a variety of different intercomparison programs that are designed to confirm that workplace monitoring results are accurate and provide the necessary external verification required by the Canadian regulators. The programs administered by the Reference Center currently include urinalysis intercomparisons for tritium, natural uranium, and 14 C, and in-vivo programs for whole-body, thorax, and thyroid monitoring. The benefits of the intercomparison programs to the participants are discussed by example. Future programs that are planned include dual spiked urine sample which contain both tritium and 14 C and the in-vivo measurement of 99m Tc. 18 refs., 1 fig., 2 tabs

  9. Evaluation of Brazilian intercomparison program data from 1991 to 1995 of radionuclide assays in environmental samples

    International Nuclear Information System (INIS)

    Vianna, Maria Elizabeth Couto M.; Tauhata, Luiz; Oliveira, Antonio Eduardo de; Oliveira, Josue Peter de; Clain, Almir Faria; Ferreira, Ana Cristina M.

    1998-01-01

    Historical radioanalytical data from the Institute of Radiation Protection and Dosimetry (IRD) national intercomparison program from 1991 to 1995 were analyzed to evaluate the performance of sixteen Brazilian laboratories in radionuclide analyses in environmental samples. Data are comprised of measurements of radionuclides in 435 spiked environmental samples distributed in fifteen intercomparison runs comprised of 955 analyses. The general and specific radionuclide performances of the participating laboratories were evaluated relative to the reference value. Data analysis encourages improvements in beta emitter measurements

  10. Intercomparison of the means of calibration relating to the measuring assemblies used in the refuelling of motor vehicles with liquefied petroleum gases

    Energy Technology Data Exchange (ETDEWEB)

    Silvert, L.; Verdonck, J.

    1982-09-01

    The calibration systems of all member countries equipped to calibrate road-side pumps delivering liquified petroleum gas (LPG) were included in the intercomparison - double water displacement gauge (F) - simple water displacement gauge (D) - ''bombola'' (I) - master meter (UK). The comparison was made with a pipe prover (piston) which circulated between the participating laboratories. The results have shown that only the simple water displacement gauge and the pipe prover have adequate properties for the metrological calibration.

  11. Intercomparison program of personal dosemeters in the Argentine Republic

    International Nuclear Information System (INIS)

    Gregori, B.N.; Papadopulos, S.B.; Kunst, J.J.

    1998-01-01

    During 1997, under the auspices of the Nuclear Regulatory Authority (ARN), its was held the third exercise of intercomparison of laboratories of personal dosimetry. The dosemeters were irradiated in X-ray beams ISO quality W60, W110, W200 and gamma sources cesium 137 and cobalt 60. The irradiation were performed kerma free in air and in phantom in order to study the capacity to evaluate both conditions. An extent range of doses (low-high) have been given 0.3 mSv- 20mSv in order to determine the operative performance o each laboratory. Over 19 laboratories of Argentina, participated 13 (65%) and finished the intercomparison 12 (60%) of them. The systems of dosimetry detection were based on film and TLD. During this intercomparison as inquiry about several items related with the laboratories have been made. In this work are shown the individual laboratory results of the intercomparison related with the acceptance curve criteria ICRP 60 and 55. (author)

  12. Intercomparison of 30+ years of AVHRR and Landsat-5 TM Surface Reflectance using Multiple Pseudo-Invariant Calibration Sites

    Science.gov (United States)

    Santamaría-Artigas, A. E.; Franch, B.; Vermote, E.; Roger, J. C.; Justice, C. O.

    2017-12-01

    The 30+ years daily surface reflectance long term data record (LTDR) from the Advanced Very High Resolution Radiometer (AVHRR) is a valuable source of information for long-term studies of the Earth surface. This LTDR was generated by combining observations from multiple AVHRR sensors aboard different NOAA satellites starting from the early 1980s, and due to the lack of on-board calibration its quality should be evaluated. Previous studies have used observations from the Moderate Resolution Imaging Spectroradiometer (MODIS) over pseudo-invariant calibration sites (PICS) as a calibrated reference to assess the performance of AVHRR products. However, this limits the evaluation to the period after MODIS launch. In this work, the AVHRR surface reflectance LTDR was evaluated against Landsat-5 Thematic Mapper (TM) data using observations from 4 well known pseudo-invariant calibration sites (i.e. Sonoran, Saharan, Sudan1, and Libya4) over an extended time period (1984-2011). For the intercomparison, AVHRR and TM observations of each site were extracted and averaged over a 20 km x 20 km area and aggregated to monthly mean values. In order to account for the spectral differences between sensors, Hyperion hyperspectral data from the Sonoran and Libya4 sites were convolved with sensor-specific relative spectral responses, and used to compute spectral band adjustment factors (SBAFs). Results of the intercomparison are reported in terms of the root mean square difference (RMSD) and determination coefficient (r2). In general, there is good agreement between the surface reflectance products from both sensors. The overall RMSD and r2 for all the sites and AVHRR/TM combinations were 0.03 and 0.85 for the red band, and 0.04 and 0.81 for the near-infrared band. These results show the strong performance of the AVHRR surface reflectance LTDR through all of the considered period. Thus, remarking its usefulness and value for long term Earth studies. Figure 1 shows the red (filled markers

  13. Intercomparison programme of dose calibration used in nuclear medicine center in Malaysia

    International Nuclear Information System (INIS)

    Norhayati Abdullah; Abdul Aziz Mohd Ramli; Muhammad Jamal Md Isa; Siti Sara Deraman; Shahrul Azlan Azizan; Nor Azlin Azraai; Md Khairusalih Md Zin

    2010-01-01

    Calibration of dose calibrator is significant in order to ensure that the equipment operates optimally and provides accurate and reliable measurements of the total activity of radiopharmaceuticals before being administered into the patients. Through this work, the response between the secondary standard dose calibrator and users radioactivity measurement are obtained by using standard sources such as 57 Co, 133 Ba, 1 '3 7 Cs and 60 Co. The calibration procedure is in accordance with the NPLs (National Physical Laboratory, United Kingdom) document; Guide No. 93[1] and the IAEA (International Atomic Energy Agency) Technical Report Series No. 454 [2] is used as a reference for maintaining secondary standard dose calibrator. A total of 21 units of dose calibrator from eight nuclear medicine departments comprising five hospitals, two medical centres and one production laboratory were calibrated. The measurement results were inter compared with the national standard equipment and a baseline data was established for future comparison as well as dose optimization purposes. Results showed that the overall response of all dose calibrators are within NPLs tolerance limit of ±10 % except for 5 units which exceed the tolerance limit for radionuclide 133 Ba and 57 Co.(author)

  14. HPS instrument calibration laboratory accreditation program

    Energy Technology Data Exchange (ETDEWEB)

    Masse, F.X; Eisenhower, E.H.; Swinth, K.L.

    1993-12-31

    The purpose of this paper is to provide an accurate overview of the development and structure of the program established by the Health Physics Society (HPS) for accrediting instrument calibration laboratories relative to their ability to accurately calibrate portable health physics instrumentation. The purpose of the program is to provide radiation protection professionals more meaningful direct and indirect access to the National Institute of Standards and Technology (NIST) national standards, thus introducing a means for improving the uniformity, accuracy, and quality of ionizing radiation field measurements. The process is designed to recognize and document the continuing capability of each accredited laboratory to accurately perform instrument calibration. There is no intent to monitor the laboratory to the extent that each calibration can be guaranteed by the program; this responsibility rests solely with the accredited laboratory.

  15. Intercomparison of hydrological model structures and calibration approaches in climate scenario impact projections

    Science.gov (United States)

    Vansteenkiste, Thomas; Tavakoli, Mohsen; Ntegeka, Victor; De Smedt, Florimond; Batelaan, Okke; Pereira, Fernando; Willems, Patrick

    2014-11-01

    The objective of this paper is to investigate the effects of hydrological model structure and calibration on climate change impact results in hydrology. The uncertainty in the hydrological impact results is assessed by the relative change in runoff volumes and peak and low flow extremes from historical and future climate conditions. The effect of the hydrological model structure is examined through the use of five hydrological models with different spatial resolutions and process descriptions. These were applied to a medium sized catchment in Belgium. The models vary from the lumped conceptual NAM, PDM and VHM models over the intermediate detailed and distributed WetSpa model to the fully distributed MIKE SHE model. The latter model accounts for the 3D groundwater processes and interacts bi-directionally with a full hydrodynamic MIKE 11 river model. After careful and manual calibration of these models, accounting for the accuracy of the peak and low flow extremes and runoff subflows, and the changes in these extremes for changing rainfall conditions, the five models respond in a similar way to the climate scenarios over Belgium. Future projections on peak flows are highly uncertain with expected increases as well as decreases depending on the climate scenario. The projections on future low flows are more uniform; low flows decrease (up to 60%) for all models and for all climate scenarios. However, the uncertainties in the impact projections are high, mainly in the dry season. With respect to the model structural uncertainty, the PDM model simulates significantly higher runoff peak flows under future wet scenarios, which is explained by its specific model structure. For the low flow extremes, the MIKE SHE model projects significantly lower low flows in dry scenario conditions in comparison to the other models, probably due to its large difference in process descriptions for the groundwater component, the groundwater-river interactions. The effect of the model

  16. Intercomparison of integrated IASI and AATSR calibrated radiances at 11 and 12 μm

    Directory of Open Access Journals (Sweden)

    R. J. Parker

    2009-09-01

    Full Text Available The mission objectives of the Infrared Atmospheric Sounding Interferometer (IASI are driven by the needs of the Numerical Weather Prediction (NWP and climate monitoring communities. These objectives rely upon the IASI instrument being able to measure top of atmosphere radiances accurately. This paper presents a technique and first results for the validation of the radiometric calibration of radiances for IASI, using a cross-calibration with the Advanced Along Track Scanning Radiometer (AATSR. The AATSR is able to measure Brightness Temperature (BT to an accuracy of 30 mK, and by applying the AATSR spectral filter functions to the IASI measured radiances we are able to compare AATSR and IASI Brightness Temperatures. By choosing coincident data points that are over the sea and in clear sky conditions, a threshold of homogeneity is derived. It is found that in these homogenous conditions, the IASI BTs agree with those measured by the AATSR to within 0.3 K, with an uncertainty of order 0.1 K. The agreement is particularly good at 11 μm where the difference is less than 0.1 K. These first results indicate that IASI is meeting its target objective of 0.5 K accuracy. It is believed that a refinement of the AATSR spectral filter functions will hopefully permit a tighter error constraint on the quality of the IASI data and hence further assessment of the climate quality of the radiances.

  17. The Brazilian National Intercomparison Program (PNI/IRD/CNEN): evaluation of 15 years of data

    International Nuclear Information System (INIS)

    Tauhata, Luiz; Vianna, Maria Elizabeth Couto M.; Oliveira, Antonio Eduardo de; Ferreira, Ana Cristina; Braganca, Maura Julia C.; Clain, Almir Faria; Quelvia de Faria, Rute

    2006-01-01

    The Instituto de Radioprotecao e Dosimetria has been coordinating the National Intercomparison Program (PNI) for 15 years, from 1991 to 2005. The objective is to evaluate the analytical performance of the laboratories in low-level activity concentration radionuclide assays in environmental samples. This work presents an evaluation of PNI data from 42 intercomparison runs, which distributed to 22 Brazilian laboratories 2511 samples evaluating 5768 radionuclide assays involving 32 radionuclides in the period from 1991 to 2004. The laboratory performance was evaluated using the Normalized Standard Deviation used by the U.S. EPA. For comparison aims, the Normalized Deviation, used by BIPM was also applied. Laboratory performance were grouped and evaluated in three periods of 5 years each. The first period shows, an average value of good performance of 71.2%, the second shows an average of 78.6% and the last an average of 82.3%. Performance for each kind of radionuclide is also presented

  18. Results of the first air ion spectrometer calibration and intercomparison workshop

    Directory of Open Access Journals (Sweden)

    E. Asmi

    2009-01-01

    Full Text Available The Air Ion Spectrometer (AIS measures mobility and size distributions of atmospheric ions. The Neutral cluster and Air Ion Spectrometer (NAIS can additionally measure neutral particles. The number of the (NAIS instruments in the world is only 11. Nevertheless, they are already widely used in atmospheric ion studies, particularly related to the initial steps of new particle formation. There is no standard method applicable for calibrating the ion spectrometers in the sub-3 nm ion range. However, recent development of high resolution DMAs has enabled the size separation of small ions with good mobility resolution. For the first time, the ion spectrometers were intercompared and calibrated in a workshop, held in January–February 2008 in Helsinki, Finland. The overall goal was to experimentally determine the (NAIS transfer functions. Monomobile mobility standards, 241-Am charger ions and silver particles were generated and used as calibration aerosols. High resolution DMAs were used to size-separate the smaller (1–10 nm ions, while at bigger diameters (4–40 nm the size was selected with a HAUKE-type DMA. Negative ion mobilities were detected by (NAISs with slightly better accuracy than positive, nonetheless, both were somewhat overestimated. A linear fit of slope of one to the whole dataset of mobilities suggested that (NAISs measured the negative mobilities 1.36±0.16 times larger compared with the reference instruments. Similarly, positive mobilities were measured 1.39±0.15 times larger compared with the reference instruments. The completely monomobile mobility standards were measured with the best accuracy. The (NAIS concentrations were compared with an aerosol electrometer (AE and a condensation particle counter (CPC. At sizes below 1.5 nm (positive and 3 nm (negative the ion spectrometers detected higher concentrations while at bigger sizes they showed similar concentrations as the reference instruments. The total particle

  19. Calibration of a Micronal flame photometer model B-260. Intercomparison of the analytical results for potassium

    International Nuclear Information System (INIS)

    Alencar, Lucia Maria Laboissiere; Dalston, Regina Celia Reboucas.

    1983-01-01

    In its environmental monitoring program, NUCLEBRAS analyzes systematically environmental samples in order to determine the total alpha and beta activities. In most of these samples, 40 K is present in measurable quantities and can therefore be used for measuring beta activity since it is almost a 100% beta emitter. A method using a flame photometer for measuring the potassium concentration in water is presented. 5 refs., 28 figs., 25 tabs

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

    International Nuclear Information System (INIS)

    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

  1. Reactor operations, inspection and maintenance. PNGS Calibration Program

    International Nuclear Information System (INIS)

    Lopez, E.

    1997-01-01

    The PNGS Calibration Program is being implemented as a response to various concerns identified in recent PEER evaluations and AECB audits. Identified areas of concern were the approach to instrument calibration of Special Safety Systems (SSS). The implementation of a calibration program is a significant improvement in operating practices. A systematic and comprehensive approach to calibration of instrumentation will improve the quality of operation of the plant with a positive contribution to PNGS safety of operation and economic objectives. This paper describes the strategy to implement the proposed calibration program and describes its calibration data requirements. (DM)

  2. Latinamerican Biological Dosimetry Network (LBDNET). International Biological Dosimetry intercomparison Program (exercise 2007-2008)

    International Nuclear Information System (INIS)

    Di Giorgio, Marina; Vallerga, Maria B.; Radl, A.; Taja, Maria R.

    2009-01-01

    This paper describes the International Biological Dosimetry Intercomparison Program (exercise 2007-2008) - developed within the framework of the IAEA regional project - RLA/9/054 (Establishment of national capabilities for response to radiological and nuclear emergency) whose general objectives are: assess reproducibility inter-laboratory; identify problems and provide the necessary modifications for collaborative work in accidental situations requiring activation of mutual assistance mechanisms which will form the basis of the Organization of LBDNET. This exercise involves the laboratories of the region: Argentina (laboratory support), Brazil, Chile, Cuba, Mexico, Peru and Uruguay and the laboratory of the Autonomous University of Barcelona-Espana (Joan Francesc Barquinero and staff). Finally, these countries will meet the next time for the drafting of a final report and later publication. (author)

  3. A suitability study of the fission product phantom and the bottle manikin absorption phantom for calibration of in vivo bioassay equipment for the DOELAP accreditation testing program

    International Nuclear Information System (INIS)

    Olsen, P.C.; Lynch, T.P.

    1991-08-01

    Pacific Northwest laboratory (PNL) conducted an intercomparison study of the Fission Product phantom and the bottle manikin absorption (BOMAB) phantom for the US Department of Energy (DOE) to determine the consistency of calibration response of the two phantoms and their suitability for certification and use under a planned bioassay laboratory accreditation program. The study was initiated to determine calibration factors for both types of phantoms and to evaluate the suitability of their use in DOE Laboratory Accreditation Program (DOELAP) round-robin testing. The BOMAB was found to be more appropriate for the DOELAP testing program. 9 refs., 9 figs., 9 tabs

  4. Report of the results of the second phase of Research Coordinated Program of IAEA ''Regional Intercomparison of Personnel Dosimetry''

    International Nuclear Information System (INIS)

    Morales, J.; Diaz, E.; Hernandez, E.; Capote, E.

    1998-01-01

    In this report the results of an intercomparison program within a research coordinated program are presented. This is a second phase of the study that consisted in to evaluate the implementation of the new ICRU quantities for individual monitoring by the dosimetry laboratories. In this report the organization aspects, quality control of the irradiations performed by the reference laboratory (SSDL of the Centro de Proteccion e Higiene de las radiaciones) as well the results of the participant laboratories are included

  5. Performance of the participant laboratories in the National Intercomparison Program (PNI) in the period from 1991 to 2013

    International Nuclear Information System (INIS)

    Tauhata, Luiz; Vianna, Maria Elizabeth Couto Machado; Oliveira, Antonio Eduardo de; Braganca, Maura Julia Camara da Silva; Ferreira, Ana Cristina de Melo

    2015-01-01

    The statistical evaluation of the data of 23 years of the Brazilian Intercomparison Program shows the performance of the 24 Participant Laboratories of the country in the determination of 29 radionuclides in 10600 spiked samples of low level activity values. The results were shown a good performance and an evolution of the quality control for analyses of this kind of samples in this time period. (author)

  6. Some physico-technical aspects of the new generation of self-calibrated alanine/EPR dosimeter and results from the international intercomparison trial

    International Nuclear Information System (INIS)

    Yordanov, N.D.; Gancheva, V.

    2000-01-01

    Some physico-technical parameters of the self-calibrated alanine/EPR dosimeters are described. Principally, this new type of solid state/EPR dosimeter contains radiation sensitive diamagnetic material (in the present case, alanine), some quantity of EPR active, but radiation insensitive, substance (for example, Mn 2+ /MgO) playing roles of an internal standard and a binding material. Thus with this dosimeter the EPR spectra of alanine and the internal standard Mn 2+ are recorded simultaneously and the dose response is represented as a ratio of EPR signal intensities of alanine versus Mn 2+ as a function of absorbed dose. As a result, the data of the present study have shown that there is practically no interference of the dosimeter EPR response (expressed as the ratio I alanine /I Mn ) from the way of preparation (homogeneity), behavior after irradiation (fading of EPR signals with time, influence of different meteorological conditions) as well as specific spectrometer setting conditions. These dosimeters show satisfactory reproducibility of preparation and reading as well as stability on keeping. Thus, fulfilling the described physico-technical data of this type of dosimeters, the reproducibility of the readings is significantly improved particularly when intercomparison among different laboratories is performed. This conclusion is confirmed by independent studies of the described self-calibrated alanine/EPR dosimeters in several laboratories in Europe. Results of which are also reported. (author)

  7. A program on quality assurance and dose calibration for radiation therapy units in Venezuela

    International Nuclear Information System (INIS)

    Padilla, M.C. de; Carrizales, L.; Diaz, J.; Gutt, F.; Cozman, A.

    1996-01-01

    The results of a five year program (1988-90-91-92-93) on quality assurance and dose calibration for 12 Cobalt-60 units from public hospitals, which represents 30% of total radiation therapy units in Venezuela, are presented. The remarkable improvement in the general performance of these units can be seen in the IAEA/WHO Postal TLD Intercomparison results which gave 100% within ± 5% in 1990 and 1992, while 63% in 1990 and 44% in 1992, with errors up to 37% were obtained for the participants not included in the program. The difference between the two groups lead the government to decrete through the Gaceta Oficial de la Republica de Venezuela, Resolution G-1397 on March 3, 1993, the quality assurance and dose calibration programs shall be established for all radiation therapy installations in Venezuela. The project for the standards was developed by the SSDL physicists and it was already approbated by the Health Ministry. It is expected that the Norms will enter into effect by the end of 1994. (author). 14 refs, 1 fig., 3 tabs

  8. A program on quality assurance and dose calibration for radiation therapy units in Venezuela

    Energy Technology Data Exchange (ETDEWEB)

    Padilla, M.C. de; Carrizales, L; Diaz, J; Gutt, F; Cozman, A [Instituto Venezolano de Investigaciones Cientificas, Caracas (Venezuela). Lab. de Calibracion Dosimetrica

    1996-08-01

    The results of a five year program (1988-90-91-92-93) on quality assurance and dose calibration for 12 Cobalt-60 units from public hospitals, which represents 30% of total radiation therapy units in Venezuela, are presented. The remarkable improvement in the general performance of these units can be seen in the IAEA/WHO Postal TLD Intercomparison results which gave 100% within {+-} 5% in 1990 and 1992, while 63% in 1990 and 44% in 1992, with errors up to 37% were obtained for the participants not included in the program. The difference between the two groups lead the government to decrete through the Gaceta Oficial de la Republica de Venezuela, Resolution G-1397 on March 3, 1993, the quality assurance and dose calibration programs shall be established for all radiation therapy installations in Venezuela. The project for the standards was developed by the SSDL physicists and it was already approbated by the Health Ministry. It is expected that the Norms will enter into effect by the end of 1994. (author). 14 refs, 1 fig., 3 tabs.

  9. Remote Cloud Sensing Intensive Observation Period (RCS-IOP) millimeter-wave radar calibration and data intercomparison

    Energy Technology Data Exchange (ETDEWEB)

    Sekelsky, S.M.; Firda, J.M.; McIntosh, R.E. [Univ. of Massachusetts, Amherst, MA (United States)] [and others

    1996-04-01

    During April 1994, the University of Massachusetts (UMass) and the Pennsylvania State University (Penn State) fielded two millimeter-wave atmospheric radars in the Atmospheric Radiation Measurement Remote Cloud Sensing Intensive Operation Period (RCS-IOP) experiment. The UMass Cloud Profiling Radar System (CPRS) operates simultaneously at 33.12 GHz and 94.92 GHz through a single antenna. The Penn State radar operates at 93.95 GHz and has separate transmitting and receiving antennas. The two systems were separated by approximately 75 meters and simultaneously observed a variety of cloud types at verticle incidence over the course of the experiment. This abstract presents some initial results from our calibration efforts. An absolute calibration of the UMass radar was made from radar measurements of a trihedral corner reflector, which has a known radar cross-section. A relative calibration of between the Penn State and UMass radars is made from the statistical comparison of zenith pointing measurements of low altitude liquid clouds. Attenuation is removed with the aid of radiosonde data, and the difference in the calibration between the UMass and Penn State radars is determined by comparing the ratio of 94-GHz and 95-GHz reflectivity values to a model that accounts for parallax effects of the two antennas used in the Penn State system.

  10. A report on intercomparison studies of computer programs which respectively model: i) radionuclide migration ii) equilibrium chemistry of groundwater

    International Nuclear Information System (INIS)

    Broyd, T.W.; McD Grant, M.; Cross, J.E.

    1985-01-01

    This report describes two intercomparison studies of computer programs which respectively model: i) radionuclide migration ii) equilibrium chemistry of groundwaters. These studies have been performed by running a series of test cases with each program and comparing the various results obtained. The work forms a part of the CEC MIRAGE project (MIgration of RAdionuclides in the GEosphere) and has been jointly funded by the CEC and the United Kingdom Department of the Environment. Presentations of the material contained herein were given at plenary meetings of the MIRAGE project in Brussels in March, 1984 (migration) and March, 1985 (equilibrium chemistry) respectively

  11. Intercomparison I

    International Nuclear Information System (INIS)

    Cortes P, A.; Garcia D, O.; Becerril V, A.

    1997-01-01

    Assuming the importance that have the use of measurement procedures which yield consistent results with other laboratories it is necessary to participate in international intercomparisons. In this time, the Radioactive patterns laboratory (LPR) at Metrology Department of National Institute of Nuclear Research participated in the Quality Appraisement Program (QAP) which was organized by the Energy Department of the United States in march 1997. In this program soil samples, vegetables and contaminated air filters were distributed with different radioisotopes. This laboratory took part in the measurement and analysis of one of the air filters. This filter was contaminated with 12 radioisotopes, 7 β emissors, 4 α and γ emissors and a β pure emissor. The β - γ emissors were measured with a gamma spectrometer system with a Ge high purity detector. From the 7 activity measurements corresponding to the β, γ emissors were qualified as acceptable. In this work, the used equipment is described and the procedure followed is reported for the problem filter measurement as well as the obtained results. (Author)

  12. Intercomparison exercises

    International Nuclear Information System (INIS)

    Arunachalam, J.

    2007-01-01

    Intercomparison exercises are vital to many a national programmes. These are only tools available with the laboratories to prove their competence to an international audience and also for the accrediting agencies to assess a laboratory

  13. High-dose secondary calibration laboratory accreditation program

    Energy Technology Data Exchange (ETDEWEB)

    Humphreys, J.C. [National Institute of Standards and Technology, Gaithersburg, MD (United States)

    1993-12-31

    There is a need for high-dose secondary calibration laboratories to serve the multi-billion dollar radiation processing industry. This need is driven by the desires of industry for less costly calibrations and faster calibration-cycle response time. Services needed include calibration irradiations of routine processing dosimeters and the supply of reference standard transfer dosimeters for irradiation in the production processing facility. In order to provide measurement quality assurance and to demonstrate consistency with national standards, the high-dose secondary laboratories would be accredited by means of an expansion of an existing National Voluntary Laboratory Accreditation Program. A laboratory performance criteria document is under development to implement the new program.

  14. High-dose secondary calibration laboratory accreditation program

    International Nuclear Information System (INIS)

    Humphreys, J.C.

    1993-01-01

    There is a need for high-dose secondary calibration laboratories to serve the multi-billion dollar radiation processing industry. This need is driven by the desires of industry for less costly calibrations and faster calibration-cycle response time. Services needed include calibration irradiations of routine processing dosimeters and the supply of reference standard transfer dosimeters for irradiation in the production processing facility. In order to provide measurement quality assurance and to demonstrate consistency with national standards, the high-dose secondary laboratories would be accredited by means of an expansion of an existing National Voluntary Laboratory Accreditation Program. A laboratory performance criteria document is under development to implement the new program

  15. Health Physics Society program for accreditation of calibration laboratories

    International Nuclear Information System (INIS)

    West, L.; Masse, F.X.; Swinth, K.L.

    1988-01-01

    The Health Physics Society has instituted a new program for accreditation of organizations that calibrate radiation survey instruments. The purpose of the program is to provide radiation protection professionals with an expanded means of direct and indirect access to national standards, thus introducing a means for improving the uniformity, accuracy, and quality of ionizing radiation field measurements. Secondary accredited laboratories are expected to provide a regional support basis. Tertiary accredited laboratories are expected to operate on a more local basis and provide readily available expertise to end users. The accreditation process is an effort to provide better measurement assurance for surveys of radiation fields. The status of the accreditation program, general criteria, gamma-ray calibration criteria, and x-ray calibration criteria are reviewed

  16. Calibration simulation. A calibration Monte-Carlo program for the OPAL jet chamber

    International Nuclear Information System (INIS)

    Biebel, O.

    1989-12-01

    A calibration Monte Carlo program has been developed as a tool to investigate the interdependence of track reconstruction and calibration constants. Three categories of calibration effects have been considered: The precise knowledge of sense wire positions, necessary to reconstruct the particle trajectories in the jet chamber. Included are the staggering and the sag of the sense wires as well as tilts and rotations of their support structures. The various contributions to the measured drift time, with special emphasis on the aberration due to the track angle and the presence of a transverse magnetic field. A very precise knowledge of the drift velocity and the Lorentz angle of the drift paths with respect to the drift field is also required. The effects degrading particle identification via energy loss dE/dx. Impurities of the gas mixture and saturation effects depending on the track angle as well as the influence of the pulse shaping-electronics have been studied. These effects have been parametrised with coefficients corresponding to the calibration constants required for track reconstruction. Excellent agreement with the input data has been achieved when determining calibration constants from Monte Carlo data generated with these parametrisations. (orig.) [de

  17. The program of international intercomparison of accident dosimetry; Le programme d'intercomparaison internationale de dosimetrie d'accident 10-12 juin 2002

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2002-06-01

    The French institute of radioprotection and nuclear safety (IRSN) has carried out in June 2002 an international intercomparison program for the testing of the physical and biological accident dosimetry techniques. The intercomparison is jointly organized by the IRSN and the OECD-NEA with the sustain of the European commission and the collaboration of the CEA centre of Valduc (France). About 30 countries have participated to this program. Each country has supplied its own dosimeters and biological samples which have been irradiated using the Silene reactor of CEA-Valduc or a {sup 60}Co source. These experiments allow to test the new dosimetric techniques that have been developed since the previous intercomparison program (1993) and to confirm or improve the performances of older techniques. Aside from the intercomparison exercise, this report makes a status of the known radiological accidents and of the effects of high doses of ionizing radiations on human health (symptoms, therapeutics). It explains the phenomenology of criticality accidents, the prevention means, and the history of such accidents up to the Tokai-Mura one in 1999. Finally, the dosimetry of criticality is presented with its physical and biological techniques. (J.S.)

  18. Calibration

    International Nuclear Information System (INIS)

    Greacen, E.L.; Correll, R.L.; Cunningham, R.B.; Johns, G.G.; Nicolls, K.D.

    1981-01-01

    Procedures common to different methods of calibration of neutron moisture meters are outlined and laboratory and field calibration methods compared. Gross errors which arise from faulty calibration techniques are described. The count rate can be affected by the dry bulk density of the soil, the volumetric content of constitutional hydrogen and other chemical components of the soil and soil solution. Calibration is further complicated by the fact that the neutron meter responds more strongly to the soil properties close to the detector and source. The differences in slope of calibration curves for different soils can be as much as 40%

  19. Intercomparison of 131I activity measurements in nuclear medicine

    International Nuclear Information System (INIS)

    Kim, G. Y.; Yang, H. K.; Lim, C. I.; Lee, H. K.; Jeong, H. K.

    2004-01-01

    Activity measurements in nuclear medicine using a dose calibrator have been performed for several decades and their reliability has varied. To minimise the radiation dose to patients with radionuclides, it is necessary to ensure that the sample administered is accurately assayed. Recognizing the importance of intercomparison in nuclear medicine and the need to make access to activity standards traceable to the international measurement system, the KFDA, as a national secondary standard dosimetry laboratory (SSDL), started an intercomparison program in 2002. This program was initiated by survey to all nuclear medicine centres regarding general information about their dose calibrators, radioisotopes etc. 71 nuclear medicine centres (79 dose calibrators) participated in the intercomparison program with 131 I isotope. To assess the accuracy of clinical measurements of the activity of 131 I solutions and to determine the reason for the disagreement, an intercomparison was conducted using 4 ml aliquots in 10 ml P6 vial with a total activity in the region of 10 -20 MBq. The reference time of decay for all solutions was 0:00 on 25 September 2002. The half-life used was 8.04 days. For the evaluation of solution in KFDA, a sealed, high pressure and re-entrant ionisation chamber, NPL-CRC radionuclide calibrators were used. The verification of our calibration quality was by means of a comparison with the Korea Primary Standard Laboratory (KRISS). The activity ratio of KFDA to KRISS for the 131 I solutions is 1.011. The difference between the value quoted by the clinic, A hospital and the value obtained by the KFDA, A KFDA , is expressed as a percent deviation, i.e. DEV(%) 100x(A hospital -A KFDA )/A KFDA . From the data obtained it was found that 61% of the calibrators showed a deviation within +/-5%; 23% had a deviation in the range 5% 131 I solution activity measurements, using dose calibrators in Koreas, and also to provide the participants with a traceable standard to

  20. Participation of the IPEN/CNEN/SP Environmental Diagnostic Division on programs of laboratory intercomparisons in environmental samples

    International Nuclear Information System (INIS)

    Cotrim, Marycel Barboza; Sato, Ivone Mulako; Salvador, Vera Lucia R.; Dantas, Elizabeth Sonoda Keiko; Cantagallo, Maria Ines; Lemes, Marcos Jose L.; Scapin, Marcos Antonio; Sisti, Cristina; Silveira, Elias Santana; Furusawa, Helio Akira; Pires, Maria Aparecida Faustino

    2003-01-01

    The present work presents the participation of the Environmental Diagnostic Division Laboratories (MQA) at the intercomparison national and international laboratories, (PI/SABESP - Interlaboratory Sao Paulo, Brazil, Program; Program for Interlaboratorial Analytic Quality Control of Metals in Water (CBM/COMETRO); Programa para La Calidad de las Mediciones Quimicas (PCQM/INTI) - Argentine, and the Commission d'Etablissement des Methodes d'Analyse, France (CETAMA/CEA). Those essay providers have using statistical tests such as the t-Student, Zscore and Cochran and Grubbs for the data evaluations. The obtained results are presented involving the analytical such as atomic absorption spectrometry: flame, graphite oven and hydride generation (AAS), emission spectrometry with induced plasma (ICP-OES), X-ray fluorescence WD-XRFS), ion chromatography and voltametry (VRA). The elements such as B, Al, K, Mg, Ca, Cr, Fe, Co, Cu, Zn and Pb, and the anions such as Cl-, NO 3 - , SO 4 2- and F - , were determined at trace level (mgL -1 ), and the elements such as Cr, As, Cd, Pb e Hg, at the trace level (μgL -1 ) in water matrices. The evaluation of analytical results, in the period 1997 to 2002, demonstrate a continuous improvement evidencing the importance of Laboratories participation at those type of exercises

  1. Uranium determination in natural U O2 samples for the laboratory intercomparison program of Agencia Brasileiro-Argentina de Contabilidade e Controle de Materiais Nucleares (ABACC)

    International Nuclear Information System (INIS)

    Avelar, Marta M.; Palmieri, Helena E.L.; Reis Fagundes, Oliene dos

    1997-01-01

    The modified Davies and Gray method for uranium titration to analyse nuclear materials is the procedure used by the CDTN's chemical laboratory. Its analytical performance was evaluated through the participation in the intercomparison program with the Brazilian - Argentine Agency for Accountability and Control of Nuclear Materials (ABACC). One sample of natural uranium dioxide was analysed. The precision and accuracy of the measurements are reported and discussed in this paper. (author). 7 refs., 1 fig., 2 tabs

  2. Dosimetry intercomparisons between fast neutron radiotherapy facilities

    International Nuclear Information System (INIS)

    Almond, P.R.; Smith, A.R.; Smathers, J.B.; Otte, V.A.

    1975-01-01

    Neutron dosimetry intercomparisons have been made between M.D. Anderson Hospital and Tumor Institute, Naval Research Laboratory, University of Washington Hospital, and Hammersmith Hospital. The parameters that are measured during these visits are: tissue kerma in air, tissue dose at depth of dose maximum, depth dose, beam profiles, neutron/gamma ratios and photon calibrations of ionization chambers. A preliminary report of these intercomparisons will be given including a comparison of the calculation and statement of tumor doses for each institution

  3. Intercomparison of calibration procedures of high dose rate {sup 192} Ir sources in Brazil and a proposal of a new methodology; Intercomparacao de procedimientos de calibracao de fontes de {sup 192} Ir de alta taxa de dose no Brasil e proposta de uma nova metodologia

    Energy Technology Data Exchange (ETDEWEB)

    Marechal, M.H.; Almeida, C.E. de [Laboratorio Nacional de Metrologia das Radiacoes Ionizantes IRD/CNEN. Caixa Postal 37750 CEP 22780-160 Rio de Janeiro (Brazil)

    1998-12-31

    The objective of this paper is to report the results of an intercomparison of the calibration procedures for {sup 192} Ir sources presently in use in Brazil and to proposal a calibration procedure to derive the N{sub k} for a Farmer type ionization chamber for {sup 192} Ir energy by interpolating from a {sup 60} Co gamma-rays and 250 kV x-rays calibration factors. the intercomparison results were all within {+-} 3.0 % except one case where 4.6 % was observed and latter identified as a problem with N-k value for X-rays. The method proposed by the present work make possible the improvement of the metrological coherence among the calibration laboratories and their users once the N{sub k} values could then provided by any of the members of SSDL network. (Author)

  4. The Program for Climate Model Diagnosis and Intercomparison (PCMDI) Software Development: Applications, Infrastructure, and Middleware/Networks

    Energy Technology Data Exchange (ETDEWEB)

    Williams, Dean N. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2011-06-30

    The status of and future plans for the Program for Climate Model Diagnosis and Intercomparison (PCMDI) hinge on software that PCMDI is either currently distributing or plans to distribute to the climate community in the near future. These software products include standard conventions, national and international federated infrastructures, and community analysis and visualization tools. This report also mentions other secondary software not necessarily led by or developed at PCMDI to provide a complete picture of the overarching applications, infrastructures, and middleware/networks. Much of the software described anticipates the use of future technologies envisioned over the span of next year to 10 years. These technologies, together with the software, will be the catalyst required to address extreme-scale data warehousing, scalability issues, and service-level requirements for a diverse set of well-known projects essential for predicting climate change. These tools, unlike the previous static analysis tools of the past, will support the co-existence of many users in a productive, shared virtual environment. This advanced technological world driven by extreme-scale computing and the data it generates will increase scientists’ productivity, exploit national and international relationships, and push research to new levels of understanding.

  5. Neutron dosimetry intercomparison run for verification of the neutron fluence

    International Nuclear Information System (INIS)

    Penev, I.; Kinova, L.

    2001-01-01

    For the neutron fluence verification the intercomparison runs Balakovo and KORPUS have been carried out. The participation in the international intercomparison runs shows that in order to more precisely verify the calculated values of the neutron fluence more intercomparison exercises are necessary. Due to such exercises the results improved after calibration of Nb performed and are in a very good agreement with RIIAR results in spite of the different approaches in the determination of its activity

  6. Secondary calibration laboratory for ionizing radiation laboratory accreitation program National Institute of Standards and Technology National Voluntary Laboratory Accreditation Program

    Energy Technology Data Exchange (ETDEWEB)

    Martin, P.R.

    1993-12-31

    This paper presents an overview of the procedures and requirements for accreditation under the Secondary Calibration Laboratory for Ionizing Radiation Program (SCLIR LAP). The requirements for a quality system, proficiency testing and the onsite assessment are discussed. The purpose of the accreditation program is to establish a network of secondary calibration laboratories that can provide calibrations traceable to the primary national standards.

  7. Secondary calibration laboratory for ionizing radiation laboratory accreitation program National Institute of Standards and Technology National Voluntary Laboratory Accreditation Program

    International Nuclear Information System (INIS)

    Martin, P.R.

    1993-01-01

    This paper presents an overview of the procedures and requirements for accreditation under the Secondary Calibration Laboratory for Ionizing Radiation Program (SCLIR LAP). The requirements for a quality system, proficiency testing and the onsite assessment are discussed. The purpose of the accreditation program is to establish a network of secondary calibration laboratories that can provide calibrations traceable to the primary national standards

  8. Dosimetry intercomparisons in European medical device sterilization plants

    DEFF Research Database (Denmark)

    Miller, A.; Sharpe, P.H.G.

    2000-01-01

    Dosimetry intercomparisons have been carried out involving two-thirds of all European radiation sterilization facilities. Dosimeters for the intercomparisons were supplied by two accredited calibration laboratories. The results show good agreement, and indicate overall dosimetry accuracy of the o...... of the order of +/-5% (1 sigma) for both Co-60 and electron beam plants. (C) 2000 Elsevier Science Ltd. All rights reserved....

  9. Development of a quality assurance program for ionizing radiation secondary calibration laboratories

    International Nuclear Information System (INIS)

    Heaton, H.T. II; Taylor, A.R. Jr.

    1993-01-01

    For calibration laboratories, routine calibrations of instruments meeting stated accuracy goals are important. One method of achieving the accuracy goals is to establish and follow a quality assurance program designed to monitor all aspects of the calibration program and to provide the appropriate feedback mechanism if adjustments are needed. In the United States there are a number of organizations with laboratory accreditation programs. All existing accreditation programs require that the laboratory implement a quality assurance program with essentially the same elements in all of these programs. Collectively, these elements have been designated as a Measurement Quality Assurance (MQA) program. This paper will briefly discuss the interrelationship of the elements of an MQA program. Using the Center for Devices and Radiological Health (CDRH) X-ray Calibration Laboratory (XCL) as an example, it will focus on setting up a quality control program for the equipment in a Secondary Calibration Laboratory

  10. Development of a quality assurance program for ionizing radiation secondary calibration laboratories

    Energy Technology Data Exchange (ETDEWEB)

    Heaton, H.T. II; Taylor, A.R. Jr. [Center for Devices and Radiological Health, Rockville, MD (United States)

    1993-12-31

    For calibration laboratories, routine calibrations of instruments meeting stated accuracy goals are important. One method of achieving the accuracy goals is to establish and follow a quality assurance program designed to monitor all aspects of the calibration program and to provide the appropriate feedback mechanism if adjustments are needed. In the United States there are a number of organizations with laboratory accreditation programs. All existing accreditation programs require that the laboratory implement a quality assurance program with essentially the same elements in all of these programs. Collectively, these elements have been designated as a Measurement Quality Assurance (MQA) program. This paper will briefly discuss the interrelationship of the elements of an MQA program. Using the Center for Devices and Radiological Health (CDRH) X-ray Calibration Laboratory (XCL) as an example, it will focus on setting up a quality control program for the equipment in a Secondary Calibration Laboratory.

  11. Program of data intercomparison of radioimmunoanalysis of thyroid hormones in Mexico

    International Nuclear Information System (INIS)

    Lezama C, J.; Zambrano A, F.; Tendilla del Pozo, J.I.

    1992-05-01

    During the year of 1990 it was carried out in Latin America the Third Campaign of External Evaluation of the Quality of the Radioimmunoanalysis of Hormones related with the thyroid, like part of the activities of the ARCAL VIII Project. This campaign was carried out with samples prepared in Chile. The objective of this work it is the one of presenting the results obtained by Mexico in this program. Inside this Third Campaign 30 laboratories of Mexico were included that corresponds to 27% of the total of participants of the Region. To each laboratory was sent it a monthly sample for the measurement of T3, T4 and TSH for a period of six months. The results were processed in it whole in Argentina and also, those of Mexico were also processed locally using the Buenos Aires program for personal computer. The results of 72% of the national laboratories were inside two standard deviations for T3, 87% for T4 and 33% for TSH. In a first approach it is observed that the determination of TSH is the one that presents bigger problem, not existing difference among using the technique of RIA or that of IRMA and that the measurement of the T3 is the one that presents a greater variation in connection with the mark of used reagents. (Author)

  12. Quality assurance programs at the PNL calibrations laboratory

    International Nuclear Information System (INIS)

    Piper, R.K.; McDonald, J.C.; Fox, R.A.; Eichner, F.N.

    1993-03-01

    The calibrations laboratory at Pacific Northwest Laboratory (PNL) serves as a radiological standardization facility for personnel and environmental dosimetry and radiological survey instruments. As part of this function, the calibrations laboratory must maintain radiological reference fields with calibrations traceable to the National Institute of Standards and Technology (NIST). This task is accomplished by a combination of (1) sources or reference instruments calibrated at or by NIST, (2) measurement quality assurance (MQA) interactions with NIST, and (3) rigorous internal annual and quarterly calibration verifications. This paper describes a representative sample of the facilities, sources, and actions used to maintain accurate and traceable fields

  13. The role of a certified calibration laboratory in a station's measuring and test equipment calibration, repair, and documentation program

    International Nuclear Information System (INIS)

    Ebenstreit, K.; MacIntosh, N.

    1995-01-01

    This paper outlines the role of a Certified Calibration Laboratory in- ensuring that the requirements of Measuring and Test Equipment calibration, identification, and traceability are met and documented. The Nuclear environment is one which is subject to influences from numerous 'quality agents'. One of the fields which comes under the scrutiny of the quality agents is that of equipment calibration and repair (both field components and M and TE). There is a responsibility to produce a superior product for the Ontario Consumer. The maintenance and calibration of Station Systems and their components have a direct impact on this output. The Measuring and Test Equipment element in each of these needs can be addressed by having a defined group of Maintenance Staff to execute a Measuring and Test Equipment Program which meets specific parameters. (author)

  14. Results of the dosimetry intercomparison

    International Nuclear Information System (INIS)

    Dure, Elsa S.

    2000-07-01

    The appropriate way to verify the accuracy of the results of dose reported by the laboratories that offer lend personal dosimetry service is in the periodic participation of round of intercomparison dosimetry, undertaken by laboratories whose standards are trace (Secondary Laboratory). The Laboratory of External Personal Dosimetry of the CNEA-PY has participated in three rounds of intercomparison. The first two were organized in the framework of the Model Project RLA/9/030 RADIOLOGICAL WASTE SECURITY, and the irradiations were carried out in the Laboratory of Regional Calibration of the Center of Nuclear Technology Development, Belo Horizonte-Brazil (1998) and in the National Laboratory of Metrology of the ionizing radiations of the Institute of Radioprotection and Dosimetry, Rio de Janeiro-Brazil (1999). The third was organized by the IAEA and the irradiations were made in the Physikalisch-Technische Bundesanstalt PTB, Braunschweig - Federal Republic of Germany (1999-2000) [es

  15. Calibration of ADRET voltage generator type CV102. Program CODAV

    International Nuclear Information System (INIS)

    Lagarde, Gerard.

    1978-07-01

    The CODAV programm studied by the Metrology SES/SME laboratory is used for the calibration of ADRET voltage generator type CV.102. A JCAM.10 microcomputer run the measurement cycle and the printout of the results [fr

  16. The UV-A and visible solar irradiance spectrum: inter-comparison of absolutely calibrated, spectrally medium resolution solar irradiance spectra from balloon- and satellite-borne measurements

    Directory of Open Access Journals (Sweden)

    W. Gurlit

    2005-01-01

    Full Text Available Within the framework of the ENVISAT/-SCIAMACHY satellite validation, solar irradiance spectra are absolutely measured at moderate resolution in the UV/visible spectral range (in the UV from 316.7-418 nm and the visible from 400-652 nm at a full width half maximum resolution of 0.55 nm and 1.48 nm, respectively from aboard the azimuth-controlled LPMA/DOAS balloon gondola at around 32 km balloon float altitude. After accounting for the atmospheric extinction due to Rayleigh scattering and gaseous absorption (O3 and NO2, the measured solar spectra are compared with previous observations. Our solar irradiance spectrum perfectly agrees within +0.03% with the re-calibrated Kurucz et al. (1984 solar spectrum (Fontenla et al., 1999, called MODTRAN 3.7 in the visible spectral range (415-650 nm, but it is +2.1% larger in the (370-415 nm wavelength interval, and -4% smaller in the UV-A spectral range (316.7-370 nm, when the Kurucz spectrum is convolved to the spectral resolution of our instrument. Similar comparisons of the SOLSPEC (Thuillier et al., 1997, 1998a, b and SORCE/SIM (Harder et al., 2000 solar spectra with MODTRAN 3.7 confirms our findings with the values being -0.5%, +2%, and -1.4% for SOLSPEC -0.33%, -0.47%, and -6.2% for SORCE/SIM, respectively. Comparison of the SCIAMACHY solar spectrum from channels 1 to 4 (- re-calibrated by the University of Bremen - with MODTRAN 3.7 indicates an agreement within -0.4% in the visible spectral range (415-585 nm, -1.6% within the 370-415 nm, and -5.7% within 325-370 nm wavelength interval, in agreement with the results of the other sensors. In agreement with findings of Skupin et al. (2002 our study emphasizes that the present ESA SCIAMACHY level 1 calibration is systematically +15% larger in the considered wavelength intervals when compared to all available other solar irradiance measurements.

  17. Intercomparison measurements of activity of 99mTc and 131I in nuclear medicine services at Recife city, Pernambuco state, Brazil

    International Nuclear Information System (INIS)

    Barreto, F.C.P.; Santos, M.A.P dos; Oliveira, M.L.; Lima, F.F. de

    2007-01-01

    The aim of this work is to present the results of the first round of intercomparison measurements of activity of 99m Tc and 131 I. This round was carried out in Recife/PE. Six nuclear medicine services (NMS), public and private, participated in this intercomparison. Additionally to the activity measurement, some information about equipment (calibration and quality control program) and human resources was obtained. All NMS participants complied with the limit established by CNEN for the accuracy of measurement (+- 10%) for 99m Tc and 131 I. Measurements will be repeated for 99m Tc and 131 I, and additional rounds will be performed including different radionuclides. (author)

  18. Argentine Republic intercomparison programme for personal dosimeters

    International Nuclear Information System (INIS)

    Gregori, Beatriz N.; Papadopulos, Susana B.; Kunst, Juan J.; Cruzate, Juan A.; Saravi, Margarita C.

    2004-01-01

    In 1997 an Intercomparison Program for individual monitoring started in order to test (on a voluntary basis) the performance in absorbed dose and personal dose equivalent determinations. The aim of the program was also to gain some insight into the general aspects related to the type of the personnel dosimeter used, the calibration procedures, the phantom spectral dependence and the management of radiological quantities. The Regional Reference Center for Dosimetry (CCR), of the Argentine National Atomic Energy Commission and the Physical Dosimetry Laboratory of the Argentine National Regulatory Authority, performed the irradiations. Those were done free air and on ICRU phantom, using X-ray, quality ISO: W60, W80, W110 and W200; and 137 Cs and 60 Co gamma rays, normal and angular (0, 30, 60 degrees) incidence. In the framework of the Program, an upgraded workshop took place and the national standard, IRAM 17146, was elaborated as well. In this work, the laboratories performance and its temporal evolution is shown from 1997 up to 2002. The suggestions to improve their performance are also included. (author)

  19. The influence of uncertainties of measurements in laboratory performance evaluation by intercomparison program in radionuclide analyses of environmental samples

    International Nuclear Information System (INIS)

    Tauhata, L.; Vianna, M.E.; Oliveira, A.E. de; Clain, A.F.; Ferreira, A.C.M.; Bernardes, E.M.

    2000-01-01

    The accuracy and precision of results of the radionuclide analyses in environmental samples are widely claimed internationally due to its consequences in the decision process coupled to evaluation of environmental pollution, impact, internal and external population exposure. These characteristics of measurement of the laboratories can be shown clearly using intercomparison data, due to the existence of a reference value and the need of three determinations for each analysis. In intercomparison studies accuracy in radionuclide assays in low-level environmental samples has usually been the main focus in performance evaluation and it can be estimated by taking into account the deviation between the experimental laboratory mean value and the reference value. The laboratory repeatability of measurements or their standard deviation is seldom included in performance evaluation. In order to show the influence of the uncertainties in performance evaluation of the laboratories, data of 22 intercomparison runs which distributed 790 spiked environmental samples to 20 Brazilian participant laboratories were compared, using the 'Normalised Standard Deviation' as statistical criteria for performance evaluation of U.S.EPA. It mainly takes into account the laboratory accuracy and the performance evaluation using the same data classified by normalised standard deviation modified by a weight reactor that includes the individual laboratory uncertainty. The results show a relative decrease in laboratory performance in each radionuclide assay: 1.8% for 65 Zn, 2.8% for 40 K, 3.4 for 60 Co, 3.7% for 134 Cs, 4.0% for 137 Cs, 4.4% for Th and U nat , 4.5% for 3 H, 6.3% for 133 Ba, 8.6% for 90 Sr, 10.6% for Gross Alpha, 10.9% for 106 Ru, 11.1% for 226 Ra, 11.5% for Gross Beta and 13.6% for 228 Ra. The changes in the parameters of the statistical distribution function were negligible and the distribution remained as Gaussian type for all radionuclides analysed. Data analyses in terms of

  20. CALIBRATION, OPTIMIZATION, AND SENSITIVITY AND UNCERTAINTY ALGORITHMS APPLICATION PROGRAMMING INTERFACE (COSU-API)

    Science.gov (United States)

    The Application Programming Interface (API) for Uncertainty Analysis, Sensitivity Analysis, and Parameter Estimation (UA/SA/PE API) tool development, here fore referred to as the Calibration, Optimization, and Sensitivity and Uncertainty Algorithms API (COSU-API), was initially d...

  1. Evaluation of the results from uranium chemical analysis by potentiometric tritation method for safeguards utilization through intercomparison programs

    International Nuclear Information System (INIS)

    Araujo, R.M.S. de; Almeida, S.G. de; Bezerra, J.H.B.; Silva, S.P. da

    1990-01-01

    It was analysed three samples of uranium, two of them of UO 2 -powder, provided by IAEA and one of UO 2 (NO 3 ) 2 - solution, provided by ECN. The goal was to verify the accuracy and precision of the method used in the routine determinations carried out at the laboratories who participate of the intercomparison exercises. The method used in the analyses performed at Laboratorio de Salvaguardas of CNEN was the potentiometric titration of Davies and Gray/NBL. It was concluded that the precisions lied in the range suitable to finalities of safeguards which are of the order of 0,05% or better. The accuracies were suitable to these purposes too. The larger deviation in relation to the certified value was equal to 0,062 of uranion and the minor equal to 0,0117% of the element. These values are comparable to which obtained by the best international laboratories which carried out this kind of analyses. (author) [pt

  2. An international intercomparison of absorbed dose measurements for radiation therapy

    International Nuclear Information System (INIS)

    Taiman Kadni; Noriah Mod Ali

    2002-01-01

    Dose intercomparison on an international basis has become an important component of quality assurance measurement i.e. to check the performance of absorbed dose measurements in radiation therapy. The absorbed dose to water measurements for radiation therapy at the SSDL, MINT have been regularly compared through international intercomparison programmes organised by the IAEA Dosimetry Laboratory, Seibersdorf, Austria such as IAEA/WHO TLD postal dose quality audits and the Intercomparison of therapy level ionisation chamber calibration factors in terms of air kerma and absorbed dose to water calibration factors. The results of these intercomparison in terms of percentage deviations for Cobalt 60 gamma radiation and megavoltage x-ray from medical linear accelerators participated by the SSDL-MINT during the year 1985-2001 are within the acceptance limit. (Author)

  3. Results of the IAEA/RCA personal dosemeter intercomparison

    Energy Technology Data Exchange (ETDEWEB)

    Tsujimura, Norio; Momose, Takumaro; Hayashi, Naomi [Environment and Safety Division, Tokai Works, Japan Nuclear Cycle Development Inst., Tokai, Ibaraki (Japan)

    2000-06-01

    The intercomparison of personal dosemeters for photon was carried out between 1990 and 1996 as part of the IAEA/RCA 'strengthening of radiation protection infrastructure' project. Japan Nuclear Cycle Development Institute participated in the intercomparison as one of the in-house personal dosimetry service organizations in Japan and also served the host irradiating laboratory. This report summarizes the dose evaluation results obtained from the JNC-TLD badges in the past four intercomparison programs. In the latest intercomparison the evaluated doses agreed to the reference doses with an accuracy of 10%. (author)

  4. The instrumentation calibration reduction program (ICRP) at Northeast Utilities

    International Nuclear Information System (INIS)

    Wyckoff, R.; Blanch, P.

    1987-01-01

    Northeast Utilities (NU) funded a project to study the feasibility of determining the state of core exit thermocouple (CET) calibration without having to have direct access to the CETs. Although the CETs were the prime focus, other safety related sensors were investigated. This paper describes presumptions and methods employed in the first phase, the feasibility study. Additionally, it describes the cost/benefit analysis which can be used by any utility to determine ICRP payback

  5. Intercomparison Of Activity Measurements Of Co-58, Y-88, Ho-166m, Tc-99m, dan I-131 Between P3KRBiN and Laboratory Within BATAN And Hospitals

    International Nuclear Information System (INIS)

    Nazaroh; Ermi-Juita; Hermawan-Candra

    2003-01-01

    One way to maintain traceability and to keep consistency of the measurement result of radioactivity was intercomparison program. According with Surat Keputusan Kepala BATAN No.73/KA/IV/99, one of tasks and functions of standardization laboratory is to coordinate an intercomparison program of radioactivity measurement. In the year of 2000, intercomparison program of activity measurements between P3KRBiN and 10 laboratories within BATAN and 12 hospitals were carried out. For intercomparison of Co-58, Y-88, and Ho-166m, there were 3 laboratories within BATAN which have more than 50% difference compared with P3KRBiN measurements and for intercomparison of Tc-99m, dan I-131, there were 2 Dose-Calibrators belongs to hospitals which have more than 30% difference compared with P3KRBiN measurements. From that result it can be concluded that intercomparison of activity measurements are very important and needs continuously to maintain traceability and to keep consistency of measurement result. (author)

  6. Primary calibrations of radionuclide solutions and sources for the EML quality assessment program

    Energy Technology Data Exchange (ETDEWEB)

    Fisenne, I.M. [Dept. of Energy, New York, NY (United States)

    1993-12-31

    The quality assurance procedures established for the operation of the U.S. Department of Energy`s Environmental Measurements Laboratory (DOE-EML`s) Quality Assessment Program (QAP) are essentially the same as those that are in effect for any EML program involving radiometric measurements. All these programs have at their core the use of radionuclide standards for their instrument calibration. This paper focuses on EML`s approach to the acquisition, calibration and application of a wide range of radionuclide sources that are required to meet its programmatic needs.

  7. Calibration of a micro simulation program for a Chinese city

    NARCIS (Netherlands)

    Jie, L.; Fangfang, Z.; Van Zuylen, H.J.; Shoufeng, L.

    2011-01-01

    Micro simulation programs are often used to assess the quality of traffic conditions. They are especially suited to evaluate possible control scenarios in advance, so that the scenarios can be selected and optimized before implementation. Of course, the simulation programs should be valid for the

  8. Computer programs for TRIGA calibration, burnup evaluation, and bookkeeping

    International Nuclear Information System (INIS)

    Nelson, George W.

    1978-01-01

    Several computer programs have been developed at the University of Arizona to assist the direction and operation of the TRIGA Reactor Laboratory. The programs fall into the following three categories: 1. Programs for calculation of burnup of each fuel element in the reactor core, for maintaining an inventory of fuel element location and fissile content at any time, and for evaluation of the reactivity effects of burnup or proposed fuel element rearrangement in the core. 2. Programs for evaluation, function fitting, and tabulation of control rod measurements. 3. Bookkeeping programs to summarize and tabulate reactor runs and irradiations according to time, energy release, purpose, responsible party, etc. These summarized data are reported in an annual operating report for the facility. The use of these programs has saved innumerable hours of repetitious work, assuring more accurate, objective results, and requiring a minimum of effort to repeat calculations when input data are modified. The programs are written in FORTRAN-IV, and have been used on a CDC-6400 computer. (author)

  9. MP.EXE Microphone pressure sensitivity calibration calculation program

    DEFF Research Database (Denmark)

    Rasmussen, Knud

    1999-01-01

    MP.EXE is a program which calculates the pressure sensitivity of LS1 microphones as defined in IEC 61094-1, based on measurement results performed as laid down in IEC 61094-2.A very early program was developed and written by K. Rasmussen. The code of the present heavily extended version is writte...... by E.S. Olsen.The present manual is written by K.Rasmussen and E.S. Olsen....

  10. Participation of the Nuclear Regulatory Authority in the uranium urinalysis intercomparisons

    International Nuclear Information System (INIS)

    Bonino, Nestor O.; Palacios, Miguel A.; Serdeiro, Nelida H.

    1999-01-01

    In the present work the results of the participation of Nuclear Regulatory Authority (NRA) Argentina, in the Uranium Urinalysis Intercomparison Program administered by the National Calibration Reference Centre for Bioassay, Radiation Protection Bureau, Health Canada, are detailed. This work is referred to the three participations of NRA in 1995, 1996, and 1997. The number of laboratories that have participated was 14, 12 and 12. A statistical analysis is presented. The performance criteria used for assessing the acceptability of results are those given in the American National Standard Institute (ANSI) 1989, N13.30. In addition, the applied radiochemical technique and the methodology are described. (author)

  11. Intercomparison of alpha particle spectrometry software packages

    International Nuclear Information System (INIS)

    1999-08-01

    Software has reached an important level as the 'logical controller' at different levels, from a single instrument to an entire computer-controlled experiment. This is also the case for software packages in nuclear instruments and experiments. In particular, because of the range of applications of alpha-particle spectrometry, software packages in this field are often used. It is the aim of this intercomparison to test and describe the abilities of four such software packages. The main objectives of the intercomparison were the ability of the programs to determine the peak areas and the peak area uncertainties, and the statistical control and stability of reported results. In this report, the task, methods and results of the intercomparison are presented in order to asist the potential users of such software and to stimulate the development of even better alpha-particle spectrum analysis software

  12. PA1317(L13): A linac BPM Calibration Program

    International Nuclear Information System (INIS)

    McCrory, E.

    1993-01-01

    The purpose of this program is to determine the centers of the high-energy linac (HEL) BPMs using beam information, and to compare this information with the existing surveying information. It measures directly and quantitatively the amount of quad steering in each of the HEL quads. It is hoped that this program is all that is needed to make this measurement This procedure is based on the observation of the beam position in a BPM downstream of a quad while changing the magnetic field in that quad. If the beam is centered in the quad, then this change will have no effect on the trajectory of the beam. However, if the beam is off center at the quad, changing the field will steer the beam. This measurement therefore can be used to measure the position of the beam in the quad under examination

  13. Dosimetric intercomparison in Cobalt 60 unities using TLD-100 crystals and CaSO4: Dy + Ptfe

    International Nuclear Information System (INIS)

    Gaona, E.; Azorin N, J.; Perez P, M.A.; Castillo H, M.; Flores F, F.; Guzman R, L.V.

    1999-01-01

    The purpose of this work is to design and construct a phantom in basis of thermoplastic polymer of methyl methacrylate that is reutilizable and which allows to do an analysis of the absorbed doses in thermoluminescent crystals (Tl) exposed to cobalt 60 to establish the dosimetric intercomparison in cobalt units which allows to do the follow-up of the Quality assurance programs, standardization of calibration procedures, dosimetry and TLD post intercomparison in radiotherapy. This work allows also prove new thermoluminescent materials of national manufacture developed by Juan Azorin and collaborators as the CaSO 4 : Dy + Ptfe. This is a first study which is realized in Mexico with the system crystal-phantom for aims to intercomparison in cobalt 60 units. In this work participate eight unities of cobalt 60 of different trades belonging at four radiotherapy centers. The results of the dose intercomparison of the eight unities of cobalt 60 were in the range 0.95-1.13, taking in account that the values between 0.95 and 1.05 were considered acceptable in terms of the requirements by the standing legislation. (Author)

  14. TLD Intercomparison in accelerators for radiotherapy in three Latin american countries

    International Nuclear Information System (INIS)

    Gaona, E.; Azorin N, J.; Perez, M.A.; Picon, C.; Castellanos, E.; Plazas, M.C.; Murcia, G.; Archundia, L.

    1998-01-01

    In Radiotherapy one of the objectives is to establish and to give follow up to quality assurance programs which make sure that the doses administered to the patients with cancer are a high probability of a success in external radiation. Likewise, one of the present preoccupations of the United Nations Agencies as well as the International Atomic Energy Agency and the Pan-American Health Organization is the optimal employment of the radiations in the treatment of cancer patients since the administered dose in Radiotherapy suffers considerable variations by the lack of quality assurance programs. The use of Electron linear accelerators requires a program of quality assurance that includes expert personnel, equipment and adequate facilities. The more used methodology for the dosimetry calibration and characterization of X-ray beams and high energy electrons for radiotherapy use is using a ionization chamber dosemeter calibrated in a regional secondary standardization laboratory. However, to establish and give follow up to the quality assurance programs it is necessary the dosimetric intercomparison through TLD. In this study it was designed plastic phantoms with TLD crystals and it was made its characterization to realize an absorbed dose analysis in the crystals exposed at X-ray beams 6 MV and high energy electrons 10 and 12 MeV to standardize the dosimetric procedures and proceeding to realize an International Pilot intercomparison of absorbed doses in TLD crystals in three Latin American countries: Mexico, Peru and Colombia with the participation of accelerators of five different institutions. The found results show that the majority of the measured doses with TLD in the different accelerators were in the 0.95-1.05 range though it had two cases outside of this range. The use of the phantoms with TLD crystals shows that they are of excellent aid to make analysis of the doses administered to the patients and an intercomparison of results to standardize procedures at

  15. MP.EXE, a Calculation Program for Pressure Reciprocity Calibration of Microphones

    DEFF Research Database (Denmark)

    Rasmussen, Knud

    1998-01-01

    A computer program is described which calculates the pressure sensitivity of microphones based on measurements of the electrical transfer impedance in a reciprocity calibration set-up. The calculations are performed according to the International Standard IEC 6194-2. In addition a number of options...

  16. The standard calibration instrument automation system for the atomic absorption spectrophotometer. Part 3: Program documentation

    Science.gov (United States)

    Ryan, D. P.; Roth, G. S.

    1982-04-01

    Complete documentation of the 15 programs and 11 data files of the EPA Atomic Absorption Instrument Automation System is presented. The system incorporates the following major features: (1) multipoint calibration using first, second, or third degree regression or linear interpolation, (2) timely quality control assessments for spiked samples, duplicates, laboratory control standards, reagent blanks, and instrument check standards, (3) reagent blank subtraction, and (4) plotting of calibration curves and raw data peaks. The programs of this system are written in Data General Extended BASIC, Revision 4.3, as enhanced for multi-user, real-time data acquisition. They run in a Data General Nova 840 minicomputer under the operating system RDOS, Revision 6.2. There is a functional description, a symbol definitions table, a functional flowchart, a program listing, and a symbol cross reference table for each program. The structure of every data file is also detailed.

  17. Quality assurance program plan for the Site Physical and Electrical Calibration Services Lab. Revision 1

    International Nuclear Information System (INIS)

    Carpenter, C.A.

    1995-01-01

    This Quality Assurance Program Plan (QAPP) is organized to address WHC's implementation of quality assurance requirements as they are presented as interpretive guidance endorsed by the Department of Energy (DOE) Field Office, Richland DOE Order 5700.6C Quality Assurance. The quality assurance requirements presented in this plan will assure Measuring and Test Equipment (M and TE) are in conformance with prescribed technical requirements and that data provided by testing, inspection, or maintenance are valid. This QAPP covers all activities and work elements that are variously called QA, quality control, and quality engineering regardless of the organization performing the work. This QAPP identifies the QA requirements for planning, control, and documentation of operations, modifications, and maintenance of the WHC Site Physical and Electrical Calibration Services Laboratory. The primary function of the WHC Site Physical and Electrical Calibration Services Laboratory is providing calibration, standardization, or repair service of M and TE

  18. Intercomparison Measurements Zavazna Poruba '98

    International Nuclear Information System (INIS)

    Kostial, J.; Nemcovic, V.; Cabanekova, H.; Durcik, M.; Svatosova, O.; Fueloep, M.; Buban, P.; Galbavy, V.; Dzubara, M.; Svatos, J.

    1998-01-01

    The periodical intercomparison exercises of mobile radiological laboratories was organized in order to improve the measuring methods and to gain a good basis for quality assurance. 20 teams from 10 countries were registered for the workshop from which 20 arrived and participated only as observers. There altogether 73 participants. The list of participants is enclosed in and of this report. The aims of 1998 intercomparison measurements were: (1) to compare the results of the measurements by in-situ spectrometry assuming the different distribution; (2) to improve cooperation among different institutions in Europe; (3) to test the ability of the teams to produce results at the spot; (4) to test the teams capability to produce results for Cs-137 with real distribution without having soil density and alpha/ro prior measurement. The program of the workshop consisted from two parts: field exercises and presentations. Field exercises were: (1) In-situ gamma spectrometry of natural and artificial radionuclides and their contribution to ambient dose rate over an area with heterogeneous distribution of the contamination of cesium-137 at Zavazna Poruba. (2) Dose rate measurement from cobalt-60 source; (3) Identification and determination of activity and depth of a buried source by in-situ spectrometry; (4) Search for lost sources by mobile radiological laboratory; (6) In-situ measurements and dose rate measurement above the water-level of Liptovska Mara; (6) In-situ gamma spectrometry on the bank of the dam an area Liptovsky Trnovec

  19. EURADOS intercomparison 2006 to harmonise European early warning dosimetry systems

    International Nuclear Information System (INIS)

    Dombrowski, H.; Neumaier, S.; Thompson, I. M. G.; Wissmann, F.

    2009-01-01

    In 2006, the European Radiation Dosimetry (EURADOS) Working Group on Environmental Radiation Monitoring (WG3) organised a third European intercomparison of dosimetry systems operated in national early warning networks. Similar to the intercomparisons in 1999 and 2002, the main aim of this exercise was to support the process of harmonisation of area monitoring in Europe by providing the network operators with basic information on the calibration and performance of their dosimetry systems. In order to characterise these systems, their following basic parameters were investigated: the response to terrestrial and cosmic radiation, the detectors' inherent background, the response at low dose rates, the energy dependence of the response as well as the sensitivity of the detector systems to small changes of the dose rate in a natural environmental radiation field. In the 2006 EURADOS intercomparison, scientists from seven countries participated to study the characteristics of 11 detector systems. All results are presented in terms of the operational quantity ambient dose equivalent, H * (10). The advent of this quantity has caused the development of new detector systems for area monitoring. Some of these new systems participated in a EURADOS intercomparison for the first time. The results are consistently presented together with uncertainties so that statistical effects can be distinguished from real detector features, which improves the interpretation of the results. By using the results of this intercomparison, some detectors were re-calibrated. The achievable improvements concerning harmonisation in dose-rate measurements in the natural environment are discussed. (authors)

  20. Intercomparison of 131I and 99mTc activity measurements in Brazilian nuclear medicine services

    International Nuclear Information System (INIS)

    Iwahara, Akira; De Oliveira, Antonio E.; Tauhata, Luiz; Silva, Carlos J. da; Lopes, Ricardo T.

    2001-01-01

    This work outlines the quality assurance program for the activity measurements of the most used radionuclides at Brazilian Nuclear Medicine Services (NMS). The program aims to guarantee that the patient is given the correct prescribed amount of activity in diagnostic or therapeutic applications. This accurate administration depends upon proper use and calibration of the activity meters by the NMS. Underestimation of administered activity in diagnostic practices could delay correct diagnosis disturbing the value of the investigation. On the other hand, the overestimation would be worse, mainly in therapeutic applications, because an unnecessarily high absorbed dose would be delivered to the patient. The preliminary results of intercomparison for 131 I and 99m Tc showed that many activity meters used at NMS's present problems giving results up to 41% greater than the reference values determined at the National Metrology Laboratory for Ionizing Radiation (LNMRI) which is recognized as the Brazilian authorized metrology laboratory for ionizing radiation. These results have demonstrated that the NMS should improve the accuracy of the activity measurements of the radionuclides administered to the patients and establish the traceability to the national standards of measurements. These standards are based on a pressurized well-type ionization chamber installed at LNMRI and calibrated with reference sources standardized by absolute methods. The protocol of the intercomparison and recommendations made in order to minimize errors in measuring procedures are described and results are discussed

  1. Quality control of secondary standards and calibration systems, therapy level, of National Laboratory of Metrology from Ionizing Radiations (LNMRI)

    International Nuclear Information System (INIS)

    Cecatti, E.R.; Freitas, L.C. de

    1992-01-01

    The results of quality control program of secondary standards, therapy level, and the calibration system of clinical dosemeters were analysed from 1984, when a change in the laboratory installation occurred and new standards were obtained. The national and the international intercomparisons were emphasised. The results for graphite wall chambers were compared, observing a maximum variation of about 0,6%. In the case of Delrin (TK01) wall chambers, the maximum variation was 1,7%. The results of post intercomparisons with thermoluminescent dosemeters have presented derivations lesser than 1%, securing the standards consistence at LNMRI with the international metrological system. (C.G.C.)

  2. Intercomparison of high energy neutron personnel dosimeters

    International Nuclear Information System (INIS)

    McDonald, J.C.; Akabani, G.; Loesch, R.M.

    1993-03-01

    An intercomparison of high-energy neutron personnel dosimeters was performed to evaluate the uniformity of the response characteristics of typical neutron dosimeters presently in use at US Department of Energy (DOE) accelerator facilities. It was necessary to perform an intercomparison because there are no national or international standards for high-energy neutron dosimetry. The testing that is presently under way for the Department of Energy Laboratory Accreditation Program (DOELAP) is limited to the use of neutron sources that range in energy from about 1 keV to 2 MeV. Therefore, the high-energy neutron dosimeters presently in use at DOE accelerator facilities are not being tested effectively. This intercomparison employed neutrons produced by the 9 Be(p,n) 9 B interaction at the University of Washington cyclotron, using 50-MeV protons. The resulting neutron energy spectrum extended to a maximum of approximately 50-MeV, with a mean energy of about 20-MeV. Intercomparison results for currently used dosimeters, including Nuclear Type A (NTA) film, thermoluminescent dosimeter (TLD)-albedo, and track-etch dosimeters (TEDs), indicated a wide variation in response to identical doses of high-energy neutrons. Results of this study will be discussed along with a description of plans for future work

  3. Environmental radioactivity intercomparison measurements

    International Nuclear Information System (INIS)

    2000-01-01

    In the context of the North Cotentin radioecological group set up in 1997 by the Ministry of the Environment and the Ministry of the Secretariat d'Etat a la Sante, the Swiss Federal Office of Public health, a national organization of independent status with respect to nuclear energy, conducted a series of measurements in the north Cotentin in 1998. Some sites proposed by local association 'Angry mothers' were examined in particular. This association has now taken the initiative to organize a large scale international intercomparison, ' North Cotentin 2000', in the vicinity of local nuclear installations. Besides the scientific aspect of the intercomparison, a specific aim of this intercomparison consists in providing to the local population with a real opportunity for direct exchange with participating international teams. The primary concern of the workshop is the determination, by in situ gamma spectrometry, of both natural and artificial concentrations and resulting ambient dose rates at selected marine ( beach) and terrestrial sites. A particular aim of the workshop also is to test the capacity of mobile teams to produce reliable results in the field of low level measurements on trace of special radionuclides (I 129 , Sr 90 , H 3 , C 14 , and alpha emitters) from environmental samples, using both direct ( in situ) and differed ( laboratory methods). an overview of the results obtained will be prepared for the benefit of the public. (N.C.)

  4. Broadband Outdoor Radiometer Calibration Process for the Atmospheric Radiation Measurement Program

    Energy Technology Data Exchange (ETDEWEB)

    Dooraghi, Michael [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2015-09-01

    The Atmospheric Radiation Measurement program (ARM) maintains a fleet of monitoring stations to aid in the improved scientific understanding of the basic physics related to radiative feedback processes in the atmosphere, particularly the interactions among clouds and aerosols. ARM obtains continuous measurements and conducts field campaigns to provide data products that aid in the improvement and further development of climate models. All of the measurement campaigns include a suite of solar measurements. The Solar Radiation Research Laboratory at the National Renewable Energy Laboratory supports ARM's full suite of stations in a number of ways, including troubleshooting issues that arise as part of the data-quality reviews; managing engineering changes to the standard setup; and providing calibration services and assistance to the full fleet of solar-related instruments, including pyranometers, pyrgeometers, pyrheliometers, as well as the temperature/relative humidity probes, multimeters, and data acquisition systems that are used in the calibrations performed at the Southern Great Plains Radiometer Calibration Facility. This paper discusses all aspects related to the support provided to the calibration of the instruments in the solar monitoring fleet.

  5. Results from 2010 Caliban Criticality Dosimetry Intercomparison

    Energy Technology Data Exchange (ETDEWEB)

    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.

  6. Results of the 1990 NASA/JPL balloon flight solar cell calibration program

    Science.gov (United States)

    Anspaugh, Bruce E.; Weiss, Robert S.

    1990-01-01

    The 1990 solar cell calibration balloon flight consisted of two flights, one on July 20, 1990 and the other on September 6, 1990. A malfunction occurred during the first flight, which resulted in a complete loss of data and a free fall of the payload from 120,000 ft. After the tracker was rebuilt, and several solar cell modules were replaced, the payload was reflown. The September flight was successful and met all the objectives of the program. Forty-six modules were carried to an altitude of 118,000 ft (36.0 km). Data telemetered from the modules was corrected to 28 C and to 1 a.u. The calibrated cells have been returned to the participants and can now be used as reference standards in simulator testing of cells and arrays.

  7. IAEA/ WHO TLD postal dose intercomparison results in Bangladesh

    International Nuclear Information System (INIS)

    Mollah, A.S.; Bhuiyan, N.U.; Rahman, S.

    2001-01-01

    Full text: For the accurate delivery of prescribed dose to the patients, high precision and accuracy in radiation dosimetry is required. The hospital/medical physicist is responsible for the accurate delivery of whole planned radiation doses to the patients prescribed by the radio therapist. The proper delivery of radiation doses depends upon the accurate output measurements of doses from the therapy machines. In Bangladesh, only six 60 Co units and five deep therapy machines are in use. Some more are expected to be installed soon. Still in 2001, none of the Government radiotherapy centers in Bangladesh was properly equipped with medical physicists as well as radiotherapy dosimetry equipment. Bangladesh Atomic Energy Commission (BAEC) is responsible for radiation safety in Bangladesh and BAEC has assigned Secondary Standard Dosimetry Laboratory (SSDL) of Bangladesh for providing dosimetry calibration to all radiotherapy centers in Bangladesh. The output measurements of therapy machines are performed once in a year by SSDL and the results are compared by participating in the annual TLD postal dose intercomparison program organized by IAEA/WHO SSDL Network. The absorbed dose to water is determined using IAEA dosimetry protocol (TRS 277 and 381) and water phantom of size 30 x 30 x 30 cm 3 , The measurements of SSDL are traceable to NPL of UK. The accuracy achieved in SSDL, Bangladesh has been found better than ± 3.5%, which is within the prescribed limit of dosimetry standard of IAEA. The methodology of output dose measurements in different radiotherapy centers in Bangladesh is described along with the IAEA/WHO intercomparison results

  8. CABAS: A freely available PC program for fitting calibration curves in chromosome aberration dosimetry

    International Nuclear Information System (INIS)

    Deperas, J.; Szluiska, M.; Deperas-Kaminska, M.; Edwards, A.; Lloyd, D.; Lindholm, C.; Romm, H.; Roy, L.; Moss, R.; Morand, J.; Wojcik, A.

    2007-01-01

    The aim of biological dosimetry is to estimate the dose and the associated uncertainty to which an accident victim was exposed. This process requires the use of the maximum-likelihood method for fitting a calibration curve, a procedure that is not implemented in most statistical computer programs. Several laboratories have produced their own programs, but these are frequently not user-friendly and not available to outside users. We developed a software for fitting a linear-quadratic dose-response relationship by the method of maximum-likelihood and for estimating a dose from the number of aberrations observed. The program called as CABAS consists of the main curve-fitting and dose estimating module and modules for calculating the dose in cases of partial body exposure, for estimating the minimum number of cells necessary to detect a given dose of radiation and for calculating the dose in the case of a protracted exposure. (authors)

  9. Users manual for an expert system (HSPEXP) for calibration of the hydrological simulation program; Fortran

    Science.gov (United States)

    Lumb, A.M.; McCammon, R.B.; Kittle, J.L.

    1994-01-01

    Expert system software was developed to assist less experienced modelers with calibration of a watershed model and to facilitate the interaction between the modeler and the modeling process not provided by mathematical optimization. A prototype was developed with artificial intelligence software tools, a knowledge engineer, and two domain experts. The manual procedures used by the domain experts were identified and the prototype was then coded by the knowledge engineer. The expert system consists of a set of hierarchical rules designed to guide the calibration of the model through a systematic evaluation of model parameters. When the prototype was completed and tested, it was rewritten for portability and operational use and was named HSPEXP. The watershed model Hydrological Simulation Program--Fortran (HSPF) is used in the expert system. This report is the users manual for HSPEXP and contains a discussion of the concepts and detailed steps and examples for using the software. The system has been tested on watersheds in the States of Washington and Maryland, and the system correctly identified the model parameters to be adjusted and the adjustments led to improved calibration.

  10. Modeling transducer impulse responses for predicting calibrated pressure pulses with the ultrasound simulation program Field II

    DEFF Research Database (Denmark)

    Bæk, David; Jensen, Jørgen Arendt; Willatzen, Morten

    2010-01-01

    FIELD II is a simulation software capable of predicting the field pressure in front of transducers having any complicated geometry. A calibrated prediction with this program is, however, dependent on an exact voltage-to-surface acceleration impulse response of the transducer. Such impulse response...... is not calculated by FIELD II. This work investigates the usability of combining a one-dimensional multilayer transducer modeling principle with the FIELD II software. Multilayer here refers to a transducer composed of several material layers. Measurements of pressure and current from Pz27 piezoceramic disks...... transducer model and the FIELD II software in combination give good agreement with measurements....

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

    Science.gov (United States)

    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).

  12. Feasibility study of radiophotoluminescent glass rod dosimeter postal dose intercomparison for high energy photon beam

    International Nuclear Information System (INIS)

    Rah, Jeong-Eun; Kim, Siyong; Cheong, Kwang-Ho; Lee, Jeong-Woo; Chung, Jin-Beom; Shin, Dong-Oh; Suh, Tae-Suk

    2009-01-01

    A radiophotoluminescent glass rod dosimeter (GRD) system has recently become commercially available. In this study we evaluated whether the GRD would be suitable for external dosimetric audit program in radiotherapy. For this purpose, we introduced a methodology of the absorbed dose determination with the GRD by establishing calibration coefficient and various correction factors (non-linearity dose response, fading, energy dependence and angular dependence). A feasibility test of the GRD postal dose intercomparison was also performed for eight high photon beams by considering four radiotherapy centers in Korea. In the accuracy evaluation of the GRD dosimetry established in this study, we obtained within 1.5% agreements with the ionization chamber dosimetry for the 60 Co beam. It was also observed that, in the feasibility study, all the relative deviations were smaller than 3%. Based on these results, we believe that the new GRD system has considerable potential to be used for a postal dose audit program

  13. Test program for NIS calibration to reactor thermal output in HTTR

    International Nuclear Information System (INIS)

    Nakagawa, Shigeaki; Shinozaki, Masayuki; Tachibana, Yukio; Kunitomi, Kazuhiko

    2000-03-01

    Rise-to-power test program for reactor thermal output measurement has been established to calibrate a neutron instrumentation system taking account of the characteristics of the High Temperature Engineering Test Reactor (HTTR). An error of reactor thermal output measurement was evaluated taking account of a configuration of instrumentation system. And the expected dispersion of measurement in the full power operation was evaluated from non-nuclear heat-up of primary coolant up to 213degC. From the evaluation, it was found that an error of reactor thermal output measurement would be less than ±2.0% at the rated power. This report presents the detailed program of rise-to-power test for reactor thermal output measurement and discusses its measurement error. (author)

  14. Improving the quality control program for patient dose calibrator according to IEC 60580

    International Nuclear Information System (INIS)

    Costa, Nathalia Almeida; Potiens, Maria da Penha Albuquerque

    2013-01-01

    The objective of this work was to improve the program quality control of this equipment based on the International Standard IEC 60580 - Medical electrical equipment - Dose area product meters . The initial program was established following the recommendations of IEC 61674 quoting dosimeters with ionization chambers and / or semiconductor detectors used in diagnostic X-ray image, however, the IEC 60580 is referred specifically to gauges and KAP (kerma-area product) presents additional tests. Tests included: intrinsic relative error, repeatability, scanning resolution, settling time, restarting, float values, response time and spatial uniformity of response. As a rule, all measurements are within the range characteristic of equipment performance. Thus, the PDC (Patient Dose Calibrator) again shows a device with excellent functionality and reliability in characterization tests carried out to quality control as( for the test in clinical PKA meters

  15. Writing to Learn: An Evaluation of the Calibrated Peer Review™ Program in Two Neuroscience Courses

    Science.gov (United States)

    Prichard, J. Roxanne

    2005-01-01

    Although the majority of scientific information is communicated in written form, and peer review is the primary process by which it is validated, undergraduate students may receive little direct training in science writing or peer review. Here, I describe the use of Calibrated Peer Review™ (CPR), a free, web-based writing and peer review program designed to alleviate instructor workload, in two undergraduate neuroscience courses: an upper- level sensation and perception course (41 students, three assignments) and an introductory neuroscience course (50 students; two assignments). Using CPR online, students reviewed primary research articles on assigned ‘hot’ topics, wrote short essays in response to specific guiding questions, reviewed standard ‘calibration’ essays, and provided anonymous quantitative and qualitative peer reviews. An automated grading system calculated the final scores based on a student’s essay quality (as determined by the average of three peer reviews) and his or her accuracy in evaluating 1) three standard calibration essays, 2) three anonymous peer reviews, and 3) his or her self review. Thus, students were assessed not only on their skill at constructing logical, evidence-based arguments, but also on their ability to accurately evaluate their peers’ writing. According to both student self-reports and instructor observation, students’ writing and peer review skills improved over the course of the semester. Student evaluation of the CPR program was mixed; while some students felt like the peer review process enhanced their understanding of the material and improved their writing, others felt as though the process was biased and required too much time. Despite student critiques of the program, I still recommend the CPR program as an excellent and free resource for incorporating more writing, peer review, and critical thinking into an undergraduate neuroscience curriculum. PMID:23493247

  16. Monte Carlo simulation: tool for the calibration in analytical determination of radionuclides

    International Nuclear Information System (INIS)

    Gonzalez, Jorge A. Carrazana; Ferrera, Eduardo A. Capote; Gomez, Isis M. Fernandez; Castro, Gloria V. Rodriguez; Ricardo, Niury Martinez

    2013-01-01

    This work shows how is established the traceability of the analytical determinations using this calibration method. Highlights the advantages offered by Monte Carlo simulation for the application of corrections by differences in chemical composition, density and height of the samples analyzed. Likewise, the results obtained by the LVRA in two exercises organized by the International Agency for Atomic Energy (IAEA) are presented. In these exercises (an intercomparison and a proficiency test) all reported analytical results were obtained based on calibrations in efficiency by Monte Carlo simulation using the DETEFF program

  17. RODDRP - A FORTRAN program for use in control rod calibration by the rod drop method

    International Nuclear Information System (INIS)

    Wilson, W.E.

    1972-01-01

    The different methods to measure reactivity which are applicable to control rod calibration are discussed. They include: 1) the positive period method, 2) the rod drop method, 3) the source-jerk method, 4) the rod oscillation method, and 5) the pulsed neutron method. The instrument setup used at WSU for rod drop measurements is presented. To speed up the analysis of power fall-off trace, a FORTRAN IV program called RODDRP was written to simultaneously solve the in-hour equation and relative neutron flux. The procedure for calculating the worth of the rod that produced the power trace is given. The reactivity for each time relative flux point is obtained. Conclusions about the status of the equipment are made

  18. Improvement of the quality control program of the clinical dosimeters calibration laboratory of the IPEN/CNEN-SP

    Energy Technology Data Exchange (ETDEWEB)

    Damatto, Willian B.; Potiens, Maria da Penha A.; Vivolo, Vitor, E-mail: wbdamatto@ipen.br, E-mail: mppotiens@ipen.br, E-mail: vivolo@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2013-07-01

    A set of clinical dosimeters (thimble ionization chamber coupled to an electrometer) commonly used in radiotherapy in Brazil and sent to the Calibration Laboratory of IPEN were under several tests and analysis parameters for the dosimeters behaviour were established, specifying their sensitivities and operating characteristics. Applied tests were: repeatability, reproducibility and current leakage. Thus it was possible to determine the most common defects found in these equipment and the actions that could be taken to prevent it (clinical dosimeters quality control programs). The behaviour of 167 dosimeters was analyzed and in this study, 62 of them have been tested. The main problem detected during calibration tests was current leakage, i.e. electronic noise. The tests were applied to the routine measurements at the Calibration Laboratory implementing an ideal calibration procedure. New calibration criteria were established following international recommendations. Therefore, it was made the improvement of the quality control programme of the clinical dosimeters calibration laboratory, benefiting the users of such equipment with better consistent calibration measurements. (author)

  19. Improvement of the quality control program of the clinical dosimeters calibration laboratory of the IPEN/CNEN-SP

    International Nuclear Information System (INIS)

    Damatto, Willian B.; Potiens, Maria da Penha A.; Vivolo, Vitor

    2013-01-01

    A set of clinical dosimeters (thimble ionization chamber coupled to an electrometer) commonly used in radiotherapy in Brazil and sent to the Calibration Laboratory of IPEN were under several tests and analysis parameters for the dosimeters behaviour were established, specifying their sensitivities and operating characteristics. Applied tests were: repeatability, reproducibility and current leakage. Thus it was possible to determine the most common defects found in these equipment and the actions that could be taken to prevent it (clinical dosimeters quality control programs). The behaviour of 167 dosimeters was analyzed and in this study, 62 of them have been tested. The main problem detected during calibration tests was current leakage, i.e. electronic noise. The tests were applied to the routine measurements at the Calibration Laboratory implementing an ideal calibration procedure. New calibration criteria were established following international recommendations. Therefore, it was made the improvement of the quality control programme of the clinical dosimeters calibration laboratory, benefiting the users of such equipment with better consistent calibration measurements. (author)

  20. Intercomparison measurements with albedo neutron dosimeters

    International Nuclear Information System (INIS)

    Alberts, W.G.; Kluge, H.

    1994-01-01

    Since the introduction of the albedo dosimeter as the official personal neutron dosimeter the dosimetry services concerned have participated in intercomparison measurements at the PTB. Their albedo dosimeters were irradiated in reference fields produced by unmoderated and D 2 O-moderated 252 Cf neutron sources in the standard irradiation facility of the PTB. Six fields with fluences different in energy and angle distribution could be realised in order to determine the response of the albedo dosimeter. The dose equivalent values evaluated by the services were compared with the reference values of the PTB for the directional dose equivalent H'(10). The results turned out to be essentially dependent on the evaluation method and the choice of the calibration factors. (orig.) [de

  1. International intercalibration and intercomparison programme for radon, thoron and daughters measuring equipment. Part. 1: Radon measurement

    International Nuclear Information System (INIS)

    Knutson, E.O.; Solomon, S.B.

    1986-01-01

    The International Intercalibration and Intercomparison Programme for Radon, Thoron and Daughters Monitoring Equipment, abbreviated IIIP, is a program organized jointly by Nuclear Energy Agency of the Organization for Economic Cooperation and Development and the Radiation Protection Research Programme of the Commission of European Communities. The broad purpose of the IIIP is to determine if the somewhat diverse calibration procedures used in different countries are equivalent. The general approach was to select four regional reference laboratories and entrust them with the details of project definition and execution. The four selected laboratories are: Australian Radiation Laboratory, US DOE Environmental Measurements Laboratory, UK National Radiation Protection Board, US DOI Bureau of Mines. The Organizing Committee that selected the four laboratories remained intact and served an oversight function in all work to date

  2. Intercomparisons of nine sky brightness detectors.

    Science.gov (United States)

    den Outer, Peter; Lolkema, Dorien; Haaima, Marty; van der Hoff, Rene; Spoelstra, Henk; Schmidt, Wim

    2011-01-01

    Nine Sky Quality Meters (SQMs) have been intercompared during a night time measurement campaign held in the Netherlands in April 2011. Since then the nine SQMs have been distributed across The Netherlands and form the Dutch network for monitoring night sky brightness. The goal of the intercomparison was to infer mutual calibration factors and obtain insight into the variability of the SQMs under different meteorological situations. An ensemble average is built from the individual measurements and used as a reference to infer the mutual calibration factors. Data required additional synchronization prior to the calibration determination, because the effect of moving clouds combined with small misalignments emerges as time jitter in the measurements. Initial scatter of the individual instruments lies between ±14%. Individual night time sums range from -16% to +20%. Intercalibration reduces this to 0.5%, and -7% to +9%, respectively. During the campaign the smallest luminance measured was 0.657 ± 0.003 mcd/m(2) on 12 April, and the largest value was 5.94 ± 0.03 mcd/m(2) on 2 April. During both occurrences interfering circumstances like snow cover or moonlight were absent.

  3. Intercomparisons of Nine Sky Brightness Detectors

    Directory of Open Access Journals (Sweden)

    Henk Spoelstra

    2011-10-01

    Full Text Available Nine Sky Quality Meters (SQMs have been intercompared during a night time measurement campaign held in the Netherlands in April 2011. Since then the nine SQMs have been distributed across the Netherlands and form the Dutch network for monitoring night sky brightness. The goal of the intercomparison was to infer mutual calibration factors and obtain insight into the variability of the SQMs under different meteorological situations. An ensemble average is built from the individual measurements and used as a reference to infer the mutual calibration factors. Data required additional synchronization prior to the calibration determination, because the effect of moving clouds combined with small misalignments emerges as time jitter in the measurements. Initial scatter of the individual instruments lies between ±14%. Individual night time sums range from −16% to +20%. Intercalibration reduces this to 0.5%, and −7% to +9%, respectively. During the campaign the smallest luminance measured was 0.657 ± 0.003 mcd/m2 on 12 April, and the largest value was 5.94 ± 0.03 mcd/m2 on 2 April. During both occurrences interfering circumstances like snow cover or moonlight were absent.

  4. Development and implantation of a control and data acquisition program for the calibration of instruments for diagnostic radiology

    International Nuclear Information System (INIS)

    Betti, Flavio

    2007-01-01

    Design techniques of an automatic control system implementing corrected kerma determination and shutter command in the calibration laboratory at IPEN are shown, as well as the periodic calibration program developed for a monitor chamber for several X-ray beam qualities used for diagnostic radiology and radiation protection instruments. Two reference electrometers, a multichannel secondary standard thermometer, and an absolute pressure barometer were connected to the Rs-232 interface from a PC computer equipped with a National Instruments multi function analog and digital I/O card. LabVIEW MR was chosen as programming tool, which allowed for the development of a suite of programs for both controlling the shutter timing cycles and the calibration of the monitor chamber against a reference standard. A detailed description of the methods used for troubleshooting, fine tuning of parameters and evaluation of program results is followed by an analysis showing that considerable advantages regarding reduction of time and precision improvements during the calibrations could be achieved by the use of the developed programs, particularly under adverse conditions like those found during short expositions, or instead during long irradiation intervals where fluctuation of parameters like kerma rate or room conditions (temperature or pressure) can be found. (author)

  5. Intercomparison of Environmental Nuclear Radiation Measuring

    Institute of Scientific and Technical Information of China (English)

    GAO; Fei; NI; Ning; HOU; Jin-bing; SONG; Ming-zhe

    2015-01-01

    In 2015,Radiation Metrology Division of China Institute of Atomic Energy organized an environmental monitoring of nuclear radiation measuring intercomparison,and 9laboratories attended.The intercomparison included environmental level dosemeters and protection level

  6. Intercomparison of IAEA airborne particulate matter reference material. Appendix 19

    International Nuclear Information System (INIS)

    Landsberger, Sheldon; Wu, De; Vermette, Stephen; Cizek, William

    1995-01-01

    Fifty air filters with fine and coarse fractions were prepared from NIST 2710 contaminated soil. Eighteen pairs were made and sent to seventeen laboratories of the CRP program on Applied Research on Air Pollution Using Nuclear-Related Analytical Techniques for elemental determination. The results of this intercomparison are discussed in this paper. (author)

  7. SOIL moisture data intercomparison

    Science.gov (United States)

    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.

  8. Intercomparison On Depth Dose Measurement

    International Nuclear Information System (INIS)

    Rohmah, N; Akhadi, M

    1996-01-01

    Intercomparation on personal dose evaluation system has been carried out between CSRSR-NAEA of Indonesia toward Standard Laboratory of JAERI (Japan) and ARL (Australia). The intercomparison was in 10 amm depth dose measurement , Hp (10), from the intercomparison result could be stated that personal depth dose measurement conducted by CSRSR was sufficiently good. Deviation of dose measurement result using personal dosemeter of TLD BG-1 type which were used by CSRSR in the intercomparison and routine photon personal dose monitoring was still in internationally agreed limit. Maximum deviation of reported doses by CSRSR compared to delivered doses for dosemeter irradiation by JAERI was -10.0 percent and by ARL was +29 percent. Maximum deviation permitted in personal dose monitoring is ± 50 percent

  9. Dosimetric intercomparison in Cobalt 60 unities using TLD-100 crystals and CaSO{sub 4}: Dy + Ptfe; Intercomparacion dosimetrica en unidades de cobalto 60 usando cristales de TLD-100 y CaSO{sub 4}: Dy + PTFE

    Energy Technology Data Exchange (ETDEWEB)

    Gaona, E. [Universidad Autonoma Metropolitana Xochimilco, Mexico D.F. (Mexico); Azorin N, J. [Universidad Autonoma Metropolitana Iztapalapa, Mexico D.F. (Mexico); Perez P, M.A. [Instituto Nacional de Cancerologia, Mexico D.F. (Mexico); Castillo H, M. [Centro Medico Nacional 20 de Noviembre, ISSSTE, Mexico D.F. (Mexico); Flores F, F. [Unidad de Oncologia, Centro Medico Nacional, IMSS, Mexico D.F. (Mexico); Guzman R, L.V. [Unidad de Oncologia, Hospital General de Mexico, Mexico D.F. (Mexico)

    1999-07-01

    The purpose of this work is to design and construct a phantom in basis of thermoplastic polymer of methyl methacrylate that is reutilizable and which allows to do an analysis of the absorbed doses in thermoluminescent crystals (Tl) exposed to cobalt 60 to establish the dosimetric intercomparison in cobalt units which allows to do the follow-up of the Quality assurance programs, standardization of calibration procedures, dosimetry and TLD post intercomparison in radiotherapy. This work allows also prove new thermoluminescent materials of national manufacture developed by Juan Azorin and collaborators as the CaSO{sub 4}: Dy + Ptfe. This is a first study which is realized in Mexico with the system crystal-phantom for aims to intercomparison in cobalt 60 units. In this work participate eight unities of cobalt 60 of different trades belonging at four radiotherapy centers. The results of the dose intercomparison of the eight unities of cobalt 60 were in the range 0.95-1.13, taking in account that the values between 0.95 and 1.05 were considered acceptable in terms of the requirements by the standing legislation. (Author)

  10. TLD Intercomparison in accelerators for radiotherapy in three Latin american countries; Intercomparacion TLD en aceleradores para radioterapia en tres paises latinoamericanos

    Energy Technology Data Exchange (ETDEWEB)

    Gaona, E.; Azorin N, J.; Perez, M.A.; Picon, C.; Castellanos, E.; Plazas, M.C.; Murcia, G.; Archundia, L. [Depto. El Hombre y su Ambiente. Universidad Autonoma Metropolitana, Calz. Del Hueso 1100, 04960 Mexico D.F. (Mexico)

    1998-12-31

    In Radiotherapy one of the objectives is to establish and to give follow up to quality assurance programs which make sure that the doses administered to the patients with cancer are a high probability of a success in external radiation. Likewise, one of the present preoccupations of the United Nations Agencies as well as the International Atomic Energy Agency and the Pan-American Health Organization is the optimal employment of the radiations in the treatment of cancer patients since the administered dose in Radiotherapy suffers considerable variations by the lack of quality assurance programs. The use of Electron linear accelerators requires a program of quality assurance that includes expert personnel, equipment and adequate facilities. The more used methodology for the dosimetry calibration and characterization of X-ray beams and high energy electrons for radiotherapy use is using a ionization chamber dosemeter calibrated in a regional secondary standardization laboratory. However, to establish and give follow up to the quality assurance programs it is necessary the dosimetric intercomparison through TLD. In this study it was designed plastic phantoms with TLD crystals and it was made its characterization to realize an absorbed dose analysis in the crystals exposed at X-ray beams 6 MV and high energy electrons 10 and 12 MeV to standardize the dosimetric procedures and proceeding to realize an International Pilot intercomparison of absorbed doses in TLD crystals in three Latin American countries: Mexico, Peru and Colombia with the participation of accelerators of five different institutions. The found results show that the majority of the measured doses with TLD in the different accelerators were in the 0.95-1.05 range though it had two cases outside of this range. The use of the phantoms with TLD crystals shows that they are of excellent aid to make analysis of the doses administered to the patients and an intercomparison of results to standardize procedures at

  11. Program for large scanning-measuring table calibration on-line with the TRA-1001 computer

    International Nuclear Information System (INIS)

    Kalmykova, L.P.; Ososkov, G.A.; Pogodina, G.A.; Skryl', I.I.

    1975-01-01

    A description of a programme variant for complex calibration of the system of boards BPS-2, is given in which the stage of measurements and accumulation of calibration data is separated from that of data processing on CDC-1604A computers. Stage-by-stage calibration allows for simultaneous and parallel measurements on all the 6 boards. Such a possibility of the boards' operation on a computer-controlled line has been used as checking of the operators' actions with current control of the data obtained. Mathematical formulae are followed by programmes' descriptions. Reception and accumulation of coordinates of the units of the calibrating plate, with a highly precise net of straight lines, are accomplished with the help of the DATREC programme working on a guiding TPA-1001 computer with simultaneous calibration of all the six BPS-2 boards. The DATREC programme is written in the SLANG-1 language. The CALBPS programme works on CDC-1604A computer, is written in FORTRAN, and calculates transformation coefficients and corresponding precision characteristics. The work has resulted in reducing the calibration time from 10-15 min. per board to 10-15 min. per all the 6 boards. The time of accumulation in the memory TPA-1001 and of recording on the CDC-608 tape recorder of calibration data is from 3 to 5 min.; the remaining time is spent on processing on a bigger CDC-1604A computer. Examples of typical output and certain results of calibration measurements are given

  12. Intercomparison of transuranics in sediments

    International Nuclear Information System (INIS)

    Nilsson, K.

    1981-01-01

    This paper summarizes the results of a recent intercomparison of transuranic analyses in Nordic sediments undertaken by five laboratories. Five different samplers were tested to determine their consistency and utility. Plutonium and americium were determined in all the samples and the analysis of variance is discussed. (author)

  13. Participation of the IPEN/CNEN/SP Environmental Diagnostic Division on programs of laboratory intercomparisons in environmental samples; Participacao da Divisao de Diagnostico Ambiental do IPEN/CNEN/SP em programas de intercomparacao laboratoriais em amostras ambientais

    Energy Technology Data Exchange (ETDEWEB)

    Cotrim, Marycel Barboza; Sato, Ivone Mulako; Salvador, Vera Lucia R.; Dantas, Elizabeth Sonoda Keiko; Cantagallo, Maria Ines; Lemes, Marcos Jose L.; Scapin, Marcos Antonio; Sisti, Cristina; Silveira, Elias Santana; Furusawa, Helio Akira; Pires, Maria Aparecida Faustino [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)], e-mail: mecotrim@ipen.br, e-mail: imsato@ipen.br, e-mail: vsalvado@ipen.br, e-mail: esdantas@ipen.br, e-mail: cantagal@ipen.br, e-mail: mjllemes@ipen.br, e-mail: helioaf@ipen.br, e-mail: mapires@ipen.br

    2003-07-01

    The present work presents the participation of the Environmental Diagnostic Division Laboratories (MQA) at the intercomparison national and international laboratories, (PI/SABESP - Interlaboratory Sao Paulo, Brazil, Program; Program for Interlaboratorial Analytic Quality Control of Metals in Water (CBM/COMETRO); Programa para La Calidad de las Mediciones Quimicas (PCQM/INTI) - Argentine, and the Commission d'Etablissement des Methodes d'Analyse, France (CETAMA/CEA). Those essay providers have using statistical tests such as the t-Student, Zscore and Cochran and Grubbs for the data evaluations. The obtained results are presented involving the analytical such as atomic absorption spectrometry: flame, graphite oven and hydride generation (AAS), emission spectrometry with induced plasma (ICP-OES), X-ray fluorescence WD-XRFS), ion chromatography and voltametry (VRA). The elements such as B, Al, K, Mg, Ca, Cr, Fe, Co, Cu, Zn and Pb, and the anions such as Cl-, NO{sub 3}{sup -}, SO{sub 4}{sup 2-} and F{sup -}, were determined at trace level (mgL{sup -1}), and the elements such as Cr, As, Cd, Pb e Hg, at the trace level ({mu}gL{sup -1}) in water matrices. The evaluation of analytical results, in the period 1997 to 2002, demonstrate a continuous improvement evidencing the importance of Laboratories participation at those type of exercises.

  14. The quality assurance program at K & S

    Energy Technology Data Exchange (ETDEWEB)

    Slowey, T.W. [AAPM Accredited Dosimetry Calibration Laboratory, Nashville, TN (United States)

    1993-12-31

    K & S operates the largest and one of the most comprehensive Accredited Dosimetry Calibration Laboratories (ADCLs) in the American Association of Physicists in Medicine (AAPM) secondary laboratory system. It offers calibrations covering energies from Grenz-Ray (0.03-mm Al) to cesium-137 and cobalt-60, brachytherapy source and well chamber calibrations for low-activity sources, and, recently, high-dose-rate iridium-192. The present Quality Assurance (QA) program at K & S began with the AAPM Guidelines for Accreditation (Task Group No. 22 and No. 3, 1989) and grew over the past 10 years to include all aspects of providing a private, self-supporting calibration service from a free-standing independent facility. Some aspects of the QA program were prompted by the requirements of the nuclear power industry while other parts were from national consensus standards or the experiences of staff. Redundancy and teamwork are the most important characteristics of this QA program. K & S has participated in a National Institute of Standards and Technology (NIST) measurement quality assurance (MQA) program since 1982, and, in recent years, an ADCL intralaboratory intercomparison was conducted by Task Group 3 of the Radiation Therapy Committee of the AAPM. One measure of the credibility of a QA program is consistent performance on the MQA program and the ADCL intercomparisons over the past 10 years. An equally important measure of the ability of a program to assure quality results is the frequency of reported errors.

  15. Importance of Intercomparison Exercises in Assessment of Internal Exposure by Whole-Body Counter

    International Nuclear Information System (INIS)

    Andrasi, A.

    2001-01-01

    Full text: Basic requirement for any kind of measurement is to check and prove the reliability and correctness of the measured results. Quality assurance programmes require several activities among which the participation in intercomparison exercises plays an important role. Since the determination of radioactive materials in the human body by whole-body counting technique implies many sources of uncertainties the reliability of calibration data and consequently the measured results have to be checked by participation in intercomparison quality control programmes. In these programmes mostly different kinds of phantoms simulating the human body are circulated among the participating laboratories, however sometimes contaminated persons are also subjects of intercomparison measurements. There are guidelines in several countries laid down concerning the requirements of whole-body counter measurements where the performance criteria for the relative bias, precision and minimum detectable amounts are formulated. These quantities are mostly the subject of intercomparison programmes. The whole body counter laboratory of the KFKI Atomic Energy Research Institute participated in intercomparison exercises several times in the last few years. The lessons learned during these activities helped in checking the capabilities of applied methods and measuring geometry as well as contributed in improving the accuracy of the measured results. A short overview on the previous international intercomparison exercises their main characteristics the results obtained and conclusions drawn are discussed in the paper with special attention to those in which also our laboratory participated. (author)

  16. Astrobiology Sample Analysis Program (ASAP) for Advanced Life Detection Instrumentation Development and Calibration

    Science.gov (United States)

    Glavin, Daniel; Brinkerhoff, Will; Dworkin, Jason; Eigenbrode, Jennifer; Franz, Heather; Mahaffy, Paul; Stern, Jen; Blake, Daid; Sandford, Scott; Fries, marc; hide

    2008-01-01

    Scientific ground-truth measurements for near-term Mars missions, such as the 2009 Mars Science Laboratory (MSL) mission, are essential for validating current in situ flight instrumentation and for the development of advanced instrumentation technologies for life-detection missions over the next decade. The NASA Astrobiology Institute (NAI) has recently funded a consortium of researchers called the Astrobiology Sample Analysis Program (ASAP) to analyze an identical set of homogenized martian analog materials in a "round-robin" style using both state-of-the-art laboratory techniques as well as in-situ flight instrumentation including the SAM gas chromatograph mass spectrometer and CHEMIN X-ray diffraction/fluorescence instruments on MSL and the Urey and MOMA organic analyzer instruments under development for the 2013 ExoMars missions. The analog samples studied included an Atacama Desert soil from Chile, the Murchison meteorite, a gypsum sample from the 2007 AMASE Mars analog site, jarosite from Panoche Valley, CA, a hydrothermal sample from Rio Tinto, Spain, and a "blind" sample collected during the 2007 MSL slow-motion field test in New Mexico. Each sample was distributed to the team for analysis to: (1) determine the nature and inventory of organic compounds, (2) measure the bulk carbon and nitrogen isotopic composition, (3) investigate elemental abundances, mineralogy and matrix, and (4) search for biological activity. The experimental results obtained from the ASAP Mars analog research consortium will be used to build a framework for understanding the biogeochemistry of martian analogs, help calibrate current spaceflight instrumentation, and enhance the scientific return from upcoming missions.

  17. Calibration of a Micronal flame photometer model B-260. Intercomparison of the analytical results for potassium; Calibracao de um fotometro de chama micronal modelo B-260. Intercomparacao de resultados analiticos de potassio

    Energy Technology Data Exchange (ETDEWEB)

    Alencar, Lucia Maria Laboissiere; Dalston, Regina Celia Reboucas

    1983-12-31

    In its environmental monitoring program, NUCLEBRAS analyzes systematically environmental samples in order to determine the total alpha and beta activities. In most of these samples, {sup 40} K is present in measurable quantities and can therefore be used for measuring beta activity since it is almost a 100% beta emitter. A method using a flame photometer for measuring the potassium concentration in water is presented. 5 refs., 28 figs., 25 tabs.

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

    International Nuclear Information System (INIS)

    Hill, Robin L.; Conrady, Matthew M.

    2011-01-01

    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.

  19. Primary standardization of cesium-137 for international intercomparison

    International Nuclear Information System (INIS)

    Srivastava, P.K.

    1977-01-01

    Primary standards of cesium-137 are of great importance for precise radiation measurements because, due to its simple decay-scheme and long half-life, it is widely used for the calibration of radiation detectors. Also 137 Cs is used for the measurement of fission-yield and uranium burn-up in reactor engineering studies. In view of these, an international intercomparison was organised on a limited scale to correlate the standards established at the Bhabha Atomic Research Centre (BARC), Bombay(India) and Physikalisch-Technische Bundesanstalt (PTB), West Germany. The ''efficiency tracing technique'' was developed at BARC for the primary standardization of 137 Cs for this intercomparison. Two tracers, namely 82 Br and 60 Co, were employed to trace the beta efficiency of the 4 πβ-γ coincidence counting system. It is shown that this technique offers high accuracy and inherent reliability. The ''tracing-technique'' for 137 Cs standardization is briefly described. The gravimetric method of dilution and preparation of mixed sources of 137 Cs - 82 Br and 137 Cs - 60 Co are given. The various counting parameters and settings are included. Data reduction and the estimation of systematic and statistical errors are discussed. The results of the intercomparison, which are also included, show that the agreement between the measurments of BARC and PTB is within 0.5%. (author)

  20. Monte Carlo simulation: tool for the calibration in analytical determination of radionuclides; Simulacion Monte Carlo: herramienta para la calibracion en determinaciones analiticas de radionucleidos

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez, Jorge A. Carrazana; Ferrera, Eduardo A. Capote; Gomez, Isis M. Fernandez; Castro, Gloria V. Rodriguez; Ricardo, Niury Martinez, E-mail: cphr@cphr.edu.cu [Centro de Proteccion e Higiene de las Radiaciones (CPHR), La Habana (Cuba)

    2013-07-01

    This work shows how is established the traceability of the analytical determinations using this calibration method. Highlights the advantages offered by Monte Carlo simulation for the application of corrections by differences in chemical composition, density and height of the samples analyzed. Likewise, the results obtained by the LVRA in two exercises organized by the International Agency for Atomic Energy (IAEA) are presented. In these exercises (an intercomparison and a proficiency test) all reported analytical results were obtained based on calibrations in efficiency by Monte Carlo simulation using the DETEFF program.

  1. Further AMBER and Ecolego Intercomparisons

    International Nuclear Information System (INIS)

    Maul, Philip; Robinson, Peter; Broed, Robert

    2004-01-01

    The AMBER compartmental modelling software is used by Quintessa in undertaking Performance Assessment (PA) calculations for SKI. SSI and NRPA are supporting the development of Ecolego which is based on the Matlab/Simulink general purpose modelling software for undertaking PA calculations. Intercomparison calculations using AMBER and Ecolego have been undertaken based on calculation cases considered in SKB's SR97 assessment. The reasons for undertaking such intercomparisons included: 1. to give confidence in the use of AMBER and Ecolego for whole system PA calculations for a deep repository; and 2. to provide SKI and SSI with an understanding of some of the technical issues raised by seeking to repeat the SR97 calculations with different models and software. Conclusions drawn from these intercomparisons included: 1. Both modelling packages successfully reproduced SKB's SR97 calculations for the near field, geosphere and biosphere. 2. AMBER and Ecolego calculations were typically in agreement to within one significant figure, but in several instances the SR97 documentation was not sufficiently clear to enable the implementation of the models in AMBER and Ecolego to be unambiguous. In order to gain more information on the comparisons between the two codes, additional intercomparisons have been undertaken using input data from the Vault Safety Case originally undertaken as part of an IAEA research project (ISAM). The comparisons between the AMBER and Ecolego calculations for the ISAM vault safety case have shown excellent agreement. Calculations at specified times generally agree to around three significant figures, and calculations of peak radionuclide fluxes and concentrations agree to two significant figures. This agreement is particularly good given the large number of model compartments and the inclusion of decay changes of up to six members. The most important situation where agreement may not be as good as that generally found is where radionuclides have been

  2. Total ozone measurement: Intercomparison of prototype New Zealand filter instrument and Dobson spectrophotometer

    Science.gov (United States)

    Basher, R. E.

    1978-01-01

    A five month intercomparison showed that the total ozone amounts of a prototype narrowband interference filter instrument were 7% less than those of a Dobson instrument for an ozone range of 0.300 to 0.500 atm cm and for airmasses less than two. The 7% bias was within the intercomparison calibration uncertainty. An airmass dependence in the Dobson instrument made the bias relationship airmass-dependent but the filter instrument's ozone values were generally constant to 2% up to an airmass of four. Long term drift in the bias was negligible.

  3. Results of the European Community's beta intercomparison programme of individual dosemeters in 1986

    International Nuclear Information System (INIS)

    Bigard, T.; Sequin, H.; Chartier, J.L.; Christensen, P.; Francis, T.M.; Lembo, L.

    1988-01-01

    For over 20 years, the Commission of the European Communities, in collaboration with competent laboratories in the member states, has been conducting intercomparisons of individual dosemeters with the objective of improving technique for monitoring ionizing radiation and establishing a common basis for dose assessment within the Community. These programmes not only serve the participants with an opportunity to validate their calibration and measuring procedures but also help to create a forum in which to exchange information and discuss experience with other participants. The performance and results of such an intercomparison exercise conducted in 1986 are reported here

  4. Intercomparison of characterization techniques of filter radiometers in the ultraviolet region

    International Nuclear Information System (INIS)

    Abu-Kassem, I.; Karha, P.; Harrison, N. J.; Nevas, S.; Hartree, W. S.

    2008-01-01

    Narrow-band filter radiometers at 248 nm, 313 nm, 330 nm and 368 nm wavelengths were used to compare calibration facilities of spectral (irradiance) responsivity at HUT, NPL and BNM-INM. The results are partly in agreement within the stated uncertainties. Use of demanding artefacts in the intercomparison revealed that the wavelength scales of the participating institutes deviate more than expected. Such effects cannot be seen in typical intercomparisons of spectral responsivity or spectral transmittance, where spectrally neutral samples are used.(author)

  5. Calibration of the solar UV radiometers in Finland

    Energy Technology Data Exchange (ETDEWEB)

    Leszczynski, K.; Jokela, K.; Visuri, R.; Ylianttila, L. [Finnish Centre for Radiation and Nuclear Safety, Helsinki (Finland). Non-Ionizing Radiation Lab.

    1996-12-31

    In this report, the main emphasis is given to (1) the problems associated with the basic calibration of the spectroradiometer and (2) the year-to-year variability of the calibrations of the solar UV network radiometers. Also, the results from intercomparisons of the Brewer and OL 742 spectroradiometers are included

  6. Calibration of the solar UV radiometers in Finland

    Energy Technology Data Exchange (ETDEWEB)

    Leszczynski, K; Jokela, K; Visuri, R; Ylianttila, L [Finnish Centre for Radiation and Nuclear Safety, Helsinki (Finland). Non-Ionizing Radiation Lab.

    1997-12-31

    In this report, the main emphasis is given to (1) the problems associated with the basic calibration of the spectroradiometer and (2) the year-to-year variability of the calibrations of the solar UV network radiometers. Also, the results from intercomparisons of the Brewer and OL 742 spectroradiometers are included

  7. Performance standard for dose Calibrator

    CERN Document Server

    Darmawati, S

    2002-01-01

    Dose calibrator is an instrument used in hospitals to determine the activity of radionuclide for nuclear medicine purposes. International Electrotechnical Commission (IEC) has published IEC 1303:1994 standard that can be used as guidance to test the performance of the instrument. This paper briefly describes content of the document,as well as explains the assessment that had been carried out to test the instrument accuracy in Indonesia through intercomparison measurement.Its is suggested that hospitals acquire a medical physicist to perform the test for its dose calibrator. The need for performance standard in the form of Indonesia Standard is also touched.

  8. Bico 2: second national intercomparison campaign of WBC centres working in Italy

    International Nuclear Information System (INIS)

    Castellani, C.M.; Battisti, P.; Tarroni, G.

    1998-01-01

    During the period November 1994 - May 1995 the coordinating group of WBC centres working in Italy organised the 2. national intercalibration and intercomparison campaign. A BOMAB phantom was used filled with four radionuclides gel solution with gamma energy emissions ranging between 100 keV and 2 MeV. 17 out of 21 Italian WBC centres took part in the campaign. Through the intercalibration, organised according to internationally accepted methodologies, each WBC centre could check its own calibration procedures. many intermediate data, collected for the methodologies and measurement procedures intercomparison, permitted analyses and comparison of uncertainly causes in a WBC measurement of the internal contamination. A proposal of MDA definition and assessment procedure resulted from the intercomparison campaign [it

  9. The quality assurance program at K ampersand S

    International Nuclear Information System (INIS)

    Slowey, T.W.

    1993-01-01

    K ampersand S operates the largest and one of the most comprehensive Accredited Dosimetry Calibration Laboratories (ADCLs) in the American Association of Physicists in Medicine (AAPM) secondary laboratory system. It offers calibrations covering energies from Grenz-Ray (0.03-mm Al) to cesium-137 and cobalt-60, brachytherapy source and well chamber calibrations for low-activity sources, and, recently, high-dose-rate iridium-192. The present Quality Assurance (QA) program at K ampersand S began with the AAPM Guidelines for Accreditation (Task Group No. 22 and No. 3, 1989) and grew over the past 10 years to include all aspects of providing a private, self-supporting calibration service from a free-standing independent facility. Some aspects of the QA program were prompted by the requirements of the nuclear power industry while other parts were from national consensus standards or the experiences of staff. Redundancy and teamwork are the most important characteristics of this QA program. K ampersand S has participated in a National Institute of Standards and Technology (NIST) measurement quality assurance (MQA) program since 1982, and, in recent years, an ADCL intralaboratory intercomparison was conducted by Task Group 3 of the Radiation Therapy Committee of the AAPM. One measure of the credibility of a QA program is consistent performance on the MQA program and the ADCL intercomparisons over the past 10 years. An equally important measure of the ability of a program to assure quality results is the frequency of reported errors

  10. Radiation quality assurance intercomparison studies 1974--1975

    International Nuclear Information System (INIS)

    1975-10-01

    The Quality Assurance Branch of the Monitoring Systems Research and Development Division at the U.S. Environmental Protection Agency's Environmental Monitoring and Support Laboratory-Las Vegas prepares and distributes calibrated low-level radioactive solutions to Federal, State, and private laboratories involved in environmental radiation monitoring and surveillance. These solutions are used for both the calibration of counting instruments and chemical yield determinations. Since the laboratories using these samples must have confidence in their accuracy, the Quality Assurance Branch has instituted intercomparison studies with the National Bureau of Standards and with the Energy Research and Development Administration Health and Service Laboratory. The results of the studies conducted during 1974 and 1975 are described

  11. Results of the 1973 NASA/JPL balloon flight solar cell calibration program

    Science.gov (United States)

    Yasui, R. K.; Greenwood, R. F.

    1975-01-01

    High altitude balloon flights carried 37 standard solar cells for calibration above 99.5 percent of the earth's atmosphere. The cells were assembled into standard modules with appropriate resistors to load each cell at short circuit current. Each standardized module was mounted at the apex of the balloon on a sun tracker which automatically maintained normal incidence to the sun within 1.0 deg. The balloons were launched to reach a float altitude of approximately 36.6 km two hours before solar noon and remain at float altitude for two hours beyond solar noon. Telemetered calibration data on each standard solar cell was collected and recorded on magnetic tape. At the end of each float period the solar cell payload was separated from the balloon by radio command and descended via parachute to a ground recovery crew. Standard solar cells calibrated and recovered in this manner are used as primary intensity reference standards in solar simulators and in terrestrial sunlight for evaluating the performance of other solar cells and solar arrays with similar spectral response characteristics.

  12. Intercomparison of gamma ray analysis software packages

    International Nuclear Information System (INIS)

    1998-04-01

    The IAEA undertook an intercomparison exercise to review available software for gamma ray spectra analysis. This document describes the methods used in the intercomparison exercise, characterizes the software packages reviewed and presents the results obtained. Only direct results are given without any recommendation for a particular software or method for gamma ray spectra analysis

  13. Asian/Australasian region intercalibration and intercomparison programme for radon, thoron and daughters. Asian/Australasian region radon intercomparison, September 1987 - September 1988

    Energy Technology Data Exchange (ETDEWEB)

    Peggie, J.R.; Gan, Tianghong; Solomon, S.B.

    1993-05-01

    The International Intercalibration and Intercomparison Programme for radon, thoron and daughters monitoring equipment, abbreviated IIIP, was a programme organized jointly by the Nuclear Energy Agency of the Organization for Economic Cooperation and Development and the Radiation Protection Research Programme of the Commission of European Communities. The broad purpose of the IIIP was to determine if the diverse calibration procedures used in different countries were equivalent. The general approach was to select four regional reference laboratories and entrust then with the details of project definition and execution. The Australian Radiation Laboratory (ARL) was selected to co-ordinate IIIP activities between OECD member countries in the Pacific region. As the regional programme precluded the participation of non-OECD member countries in the Western Pacific Region, an intercomparison series for radon was initiated by ARL in 1987 between twenty eight laboratories from nine countries in the Asian/Australasian region. The methodology and protocols for grab sampler, solid state nuclear track detectors (SSNTD) and charcoal measurements are described in this report. Generally the results showed reasonable agreement between the majority of laboratories for grab sampler measurements consistent with previous intercomparison. However there were large systematic differences in the results of the passive monitors for some laboratories. For all samplers, it was found that the overall random uncertainty or replication error, which included random uncertainties associated with the counting and calibration, were the main sources of variability between individual measurements of participants and the ARL reference value, with calibration uncertainties predominating. 23 tabs.

  14. Asian/Australasian region intercalibration and intercomparison programme for radon, thoron and daughters. Asian/Australasian region radon intercomparison, September 1987 - September 1988

    International Nuclear Information System (INIS)

    Peggie, J.R.; Gan, Tianghong; Solomon, S.B.

    1993-05-01

    The International Intercalibration and Intercomparison Programme for radon, thoron and daughters monitoring equipment, abbreviated IIIP, was a programme organized jointly by the Nuclear Energy Agency of the Organization for Economic Cooperation and Development and the Radiation Protection Research Programme of the Commission of European Communities. The broad purpose of the IIIP was to determine if the diverse calibration procedures used in different countries were equivalent. The general approach was to select four regional reference laboratories and entrust then with the details of project definition and execution. The Australian Radiation Laboratory (ARL) was selected to co-ordinate IIIP activities between OECD member countries in the Pacific region. As the regional programme precluded the participation of non-OECD member countries in the Western Pacific Region, an intercomparison series for radon was initiated by ARL in 1987 between twenty eight laboratories from nine countries in the Asian/Australasian region. The methodology and protocols for grab sampler, solid state nuclear track detectors (SSNTD) and charcoal measurements are described in this report. Generally the results showed reasonable agreement between the majority of laboratories for grab sampler measurements consistent with previous intercomparison. However there were large systematic differences in the results of the passive monitors for some laboratories. For all samplers, it was found that the overall random uncertainty or replication error, which included random uncertainties associated with the counting and calibration, were the main sources of variability between individual measurements of participants and the ARL reference value, with calibration uncertainties predominating. 23 tabs

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

    International Nuclear Information System (INIS)

    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 -3

  16. Photon dosimetry intercomparisons at Tygerberg and Groote Schuur hospitals

    International Nuclear Information System (INIS)

    Jones, D.T.L.; Symons, J.E.; Schreuder, A.N.; Van der Merwe, E.J.; Rossouw, A.; Hough, J.K.; Lazarus, G.L.

    1994-08-01

    A national photon dosimetry intercomparison was undertaken at 8 hospitals at the beginning of 1989 prior to the commencement of randomised clinical trials involving neutron therapy at the National Accelerator Centre. The results obtained were in agreement at all but two hospitals. Following these studies it was agreed that a uniform photon dosimetry protocol, the AAPM TG2 protocol, be adopted countrywide. The clinical program at the National Accelerator Centre is now far advanced and it was deemed appropriate to undertake a new photon dosimetry intercomparison at two local hospitals, through which all patients are referred. The procedure involved was to compare the doses measured at each hospital under specified conditions by National Accelerator staff with the doses measured by the hospital physicists using their own equipment and protocols. The results obtained were in good agreement, confirming the validity of the dosimetry techniques used. 8 refs., 8 tabs

  17. Carnegie Hubble Program: A Mid-Infrared Calibration of the Hubble Constant

    Science.gov (United States)

    Freedman, Wendy L.; Madore, Barry F.; Scowcroft, Victoria; Burns, Chris; Monson, Andy; Persson, S. Eric; Seibert, Mark; Rigby, Jane

    2012-01-01

    Using a mid-infrared calibration of the Cepheid distance scale based on recent observations at 3.6 micrometers with the Spitzer Space Telescope, we have obtained a new, high-accuracy calibration of the Hubble constant. We have established the mid-IR zero point of the Leavitt law (the Cepheid period-luminosity relation) using time-averaged 3.6 micrometers data for 10 high-metallicity, MilkyWay Cepheids having independently measured trigonometric parallaxes. We have adopted the slope of the PL relation using time-averaged 3.6micrometers data for 80 long-period Large Magellanic Cloud (LMC) Cepheids falling in the period range 0.8 < log(P) < 1.8.We find a new reddening-corrected distance to the LMC of 18.477 +/- 0.033 (systematic) mag. We re-examine the systematic uncertainties in H(sub 0), also taking into account new data over the past decade. In combination with the new Spitzer calibration, the systematic uncertainty in H(sub 0) over that obtained by the Hubble Space Telescope Key Project has decreased by over a factor of three. Applying the Spitzer calibration to the Key Project sample, we find a value of H(sub 0) = 74.3 with a systematic uncertainty of +/-2.1 (systematic) kilometers per second Mpc(sup -1), corresponding to a 2.8% systematic uncertainty in the Hubble constant. This result, in combination with WMAP7measurements of the cosmic microwave background anisotropies and assuming a flat universe, yields a value of the equation of state for dark energy, w(sub 0) = -1.09 +/- 0.10. Alternatively, relaxing the constraints on flatness and the numbers of relativistic species, and combining our results with those of WMAP7, Type Ia supernovae and baryon acoustic oscillations yield w(sub 0) = -1.08 +/- 0.10 and a value of N(sub eff) = 4.13 +/- 0.67, mildly consistent with the existence of a fourth neutrino species.

  18. Program of data intercomparison of radioimmunoanalysis of thyroid hormones in Mexico; Programa de intercomparacion de datos del radioinmunoanalisis de hormonas tiroideas en Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Lezama C, J; Zambrano A, F; Tendilla del Pozo, J I

    1992-05-15

    During the year of 1990 it was carried out in Latin America the Third Campaign of External Evaluation of the Quality of the Radioimmunoanalysis of Hormones related with the thyroid, like part of the activities of the ARCAL VIII Project. This campaign was carried out with samples prepared in Chile. The objective of this work it is the one of presenting the results obtained by Mexico in this program. Inside this Third Campaign 30 laboratories of Mexico were included that corresponds to 27% of the total of participants of the Region. To each laboratory was sent it a monthly sample for the measurement of T3, T4 and TSH for a period of six months. The results were processed in it whole in Argentina and also, those of Mexico were also processed locally using the Buenos Aires program for personal computer. The results of 72% of the national laboratories were inside two standard deviations for T3, 87% for T4 and 33% for TSH. In a first approach it is observed that the determination of TSH is the one that presents bigger problem, not existing difference among using the technique of RIA or that of IRMA and that the measurement of the T3 is the one that presents a greater variation in connection with the mark of used reagents. (Author)

  19. Result of the intercomparison exercise on radon measuring instruments and radon detectors 'bev- radon ring 2005'

    International Nuclear Information System (INIS)

    Baumgartner, A.; Maringer, F.J.; Michai, P.; Kreuziger, M.

    2006-01-01

    In spring 2005 the Federal Office of Metrology and Surveying (B.E.V.) invited all in Austria working radon measuring institutes to an intercomparison exercise at the radon calibration laboratory in the Arsenal. The aim of this intercomparison was on the one hand an objective inquiry and documentation of the current metrological potential on the section of radon measurement in Austria - both quantitative and qualitative- and on the other hand an initiative for the participating laboratories to optimize and improve their applied calibration-, measurement and analyse technique. Ten contacted Austrian radon laboratories were prepared to participate on the radon intercomparison exercise. The intercomparison exercise was carried out from 14. till 29. June at the radon calibration laboratory in the Arsenal of the B.E.V.. As radon emanation source a five stepped arranged, at the Arsenal built radon source was used. The source ( A.D.O.T.T.O. 1 is filled with a certified Ra- 226-standard solution of the Czech Metrological Institute (C.M.I.), Prag. A simple statistic based model was used for the evaluation and assessment of the results from the participants, which consider the statistic nature of the radioactive decay combined uncertainty. Altogether 183 measuring instruments participated the intercomparison exercise. Two reference measuring instruments, 22 active and 159 passive measuring instruments. The active measuring instruments formed 6 types of instruments and as passive radon detectors were 7 different types used from the participants. The positioning of the radon measuring instruments and detectors in the radon calibration laboratory was executed in regard to statistic points of view. From the active measuring instruments 17 could qualify and from the passive methods six from eight participants were in compliance to the given criteria. Radon measurements, which could have financial and economics relating implications (e.g. architectural redevelopment or

  20. A model-data intercomparison of CO2 exchange across North America: Results from the North American Carbon Program Site Synthesis

    Energy Technology Data Exchange (ETDEWEB)

    Schwalm, C.R.; Williams, C.A.; Schaefer, K.; Anderson, R.; Arain, M.A.; Baker, I.; Black, T.A.; Chen, G.; Ciais, P.; Davis, K. J.; Desai, A. R.; Dietze, M.; Dragoni, D.; Fischer, M.L.; Flanagan, L.B.; Grant, R.F.; Gu, L.; Hollinger, D.; Izaurralde, R.C.; Kucharik, C.; Lafleur, P.M.; Law, B.E.; Li, L.; Li, Z.; Liu, S.; Lokupitiya, E.; Luo, Y.; Ma, S.; Margolis, H.; Matamala, R.; McCaughey, H.; Monson, R. K.; Oechel, W. C.; Peng, C.; Poulter, B.; Price, D.T.; Riciutto, D.M.; Riley, W.J.; Sahoo, A.K.; Sprintsin, M.; Sun, J.; Tian, H.; Tonitto, C.; Verbeeck, H.; Verma, S.B.

    2011-06-01

    Our current understanding of terrestrial carbon processes is represented in various models used to integrate and scale measurements of CO{sub 2} exchange from remote sensing and other spatiotemporal data. Yet assessments are rarely conducted to determine how well models simulate carbon processes across vegetation types and environmental conditions. Using standardized data from the North American Carbon Program we compare observed and simulated monthly CO{sub 2} exchange from 44 eddy covariance flux towers in North America and 22 terrestrial biosphere models. The analysis period spans {approx}220 site-years, 10 biomes, and includes two large-scale drought events, providing a natural experiment to evaluate model skill as a function of drought and seasonality. We evaluate models' ability to simulate the seasonal cycle of CO{sub 2} exchange using multiple model skill metrics and analyze links between model characteristics, site history, and model skill. Overall model performance was poor; the difference between observations and simulations was {approx}10 times observational uncertainty, with forested ecosystems better predicted than nonforested. Model-data agreement was highest in summer and in temperate evergreen forests. In contrast, model performance declined in spring and fall, especially in ecosystems with large deciduous components, and in dry periods during the growing season. Models used across multiple biomes and sites, the mean model ensemble, and a model using assimilated parameter values showed high consistency with observations. Models with the highest skill across all biomes all used prescribed canopy phenology, calculated NEE as the difference between GPP and ecosystem respiration, and did not use a daily time step.

  1. Australian participation in international intercomparisons of environmental dosemeters

    International Nuclear Information System (INIS)

    Boas, J.F.; David, R.C.; Jones, J.

    2002-01-01

    The Environmental Measurements Laboratory of the U.S. Department of Energy has conducted international intercomparisons of environmental dosemeters at regular intervals since 1974. This paper reports the results obtained in the 10th and 11th intercomparisons by JFB and JGY at the Australian Radiation Laboratory (in 1992 and 1996 respectively) and in the 12th intercomparison by JFB and DRCT at the Australian Radiation Protection and Nuclear Safety Agency and by JGY and JJ at Australian Radiation Serviceces during 2000 and 2001. The ARL/ARPANSA measurements used a simple dosemeter holder containing two CaSO 4 :Dy impregnated Teflon discs, one unshielded and the other shielded by approximately 2.4 mm of Cu. The ARS measurements used a commercially available TLD badge case containing a CaSO 4 :Dy impregnated Teflon card. The commercial badge case was not symmetrical in design. The filtration in the front and rear sections of the commercial badge case varied from an open area to an area shielded by copper, tin and cadmium. The results obtained were generally within ±15% of the reference values measured by EML using high-pressure ionisation chambers for dosemeters exposed hi the field to environmental radiation and for dosemeters given a single exposure to 137 Cs or 241 Am at EML or an associated laboratory. Similar agreement was obtained for dosemeters exposed in the field and also given a single exposure to 137 Cs radiation. In order to obtain this measure of agreement, the dosemeters were individually calibrated and the readouts corrected for fading. Copyright (2002) Australasian Radiation Protection Society Inc

  2. Argentine intercomparison programme for personal dosimetry

    International Nuclear Information System (INIS)

    Gregori, B.N.; Papadopulos, S.B.; Cruzate, J.; Kunst, J.J.; Saravi, M.

    2005-01-01

    Full text: In 1997 began in Argentine, sponsored by Nuclear Regulatory Authority (ARN) the intercomparison program for personal dosimetry laboratories, on a voluntary basis. Up to know 6 exercises have been done. The program began with a workshop to present the quantities, personal dose equivalent, Hp(10) and extremities dose equivalent, Hs(d). The first aim of this program was to know the true sate of personal dosimetry laboratories in the country, and then introduce the personal dose equivalent, Hp(10) into the dose measurements. The Regional Reference Center for Dosimetry (CCR), belonging to CNEA and the Physical Dosimetry Laboratory of ARN performed the irradiation. Those were done air free and on ICRU phantom, using x-ray, quality ISO: W60, W110 and W200; and 137 Cs and 60 Co gamma rays. The irradiation was made following ISO 4037 (2) recommendations. There are studied the dose, energy and angular response of the different measuring system. The range of the dose analyzed was from 0.2 mSv up to 80 mSv. The beam incidence was normal and also 20 o and 60 o . The dosimeters irradiation's were performed kerma in free in air and in phantom in order to study the availability of the service to evaluate the behavior as a function of kerma free in air or Hp(10). At the same time several items have been asked to each participant referring to the action range, the detectors characteristics, the laboratory procedures, the existence of an algorithm and its use for the dosimeter evaluation and the wish to participate in a quality assurance program. The program worked in writing a standard of personal dosimetry laboratories, that was published in 2001. In this work the results of each laboratory and its performance based on the ICRP-60 and ICRP-35 acceptance criteria are shown. Also the laboratory evolution and inquiry analyses have been included. (author)

  3. A complete dosimetry experimental program in support to the core characterization and to the power calibration of the CABRI reactor. A complete dosimetry experimental program in support of the core characterization and of the power calibration of the CABRI reactor

    Energy Technology Data Exchange (ETDEWEB)

    Rodiac, F.; Hudelot, JP.; Lecerf, J.; Garnier, Y.; Ritter, G. [CEA, DEN, CAD/DER/SRES/LPRE, Cadarache, F-13108 Saint-Paul-lez-Durance, (France); Gueton, O.; Colombier, AC. [CEA, DEN, CAD/DER/SPRC/LPN, Cadarache, F-13108 Saint-Paul-lez-Durance, (France); Domergue, C. [CEA, DEN, CAD/DER/SPEx/LDCI, Cadarache, F-13108 Saint-Paul-lez-Durance, (France)

    2015-07-01

    CABRI is an experimental pulse reactor operated by CEA at the Cadarache research center. Since 1978 the experimental programs have aimed at studying the fuel behavior under Reactivity Initiated Accident (RIA) conditions. Since 2003, it has been refurbished in order to be able to provide RIA and LOCA (Loss Of Coolant Accident) experiments in prototypical PWR conditions (155 bar, 300 deg. C). This project is part of a broader scope including an overall facility refurbishment and a safety review. The global modification is conducted by the CEA project team. It is funded by IRSN, which is conducting the CIP experimental program, in the framework of the OECD/NEA project CIP. It is financed in the framework of an international collaboration. During the reactor restart, commissioning tests are realized for all equipment, systems and circuits of the reactor. In particular neutronics and power commissioning tests will be performed respectively in 2015 and 2016. This paper focuses on the design of a complete and original dosimetry program that was built in support to the CABRI core characterization and to the power calibration. Each one of the above experimental goals will be fully described, as well as the target uncertainties and the forecasted experimental techniques and data treatment. (authors)

  4. Third IAEA nuclear accident intercomparison experiment

    Energy Technology Data Exchange (ETDEWEB)

    Miric, I; Ubovic, Z

    1974-05-15

    The purpose of this report is to present the results of the International Atomic Energy Agency intercomparison experiments held at the 'Boris Kidric' Institute, Vinca, in May 1973. The experiments are parts of a multilaboratory intercomparison programme sponsored by the IAEA for the evaluation of nuclear accident dosimetry systems and eventually recommendation of dosimetry systems that will provide adequate informations in the event of a criticality accident. The previous two studies were held at the Valduc Centre near Dijon (France) in June 1970 and at the ORNL in Oak Ridge (USA), in May 1971. Parts of the intercomparison studies were coordination meetings. The topics and conclusions of the Third coordination meeting are given in the Chairman's Report of F.F. Haywood. This paper will deal, therefore, only with data concerning the Third intercomparison experiments in which the RB reactor at Vinca was used as a source of mixed radiation. (author)

  5. Report on the Intercomparison Exercises 1993

    DEFF Research Database (Denmark)

    Aminot, A.; Boer, J. de; Cofino, W.

    This report covers the intercomparison exercises - 1993 of the project Quasimeme - Quality Assurance of Information for Marine Environmental Monitoring in Europe. The report is prepared under contract for the measurement and testing programme (BCR) of the European Community....

  6. Third IAEA nuclear accident intercomparison experiment

    International Nuclear Information System (INIS)

    Miric, I.; Ubovic, Z.

    1974-05-01

    The purpose of this report is to present the results of the International Atomic Energy Agency intercomparison experiments held at the 'Boris Kidric' Institute, Vinca, in May 1973. The experiments are parts of a multilaboratory intercomparison programme sponsored by the IAEA for the evaluation of nuclear accident dosimetry systems and eventually recommendation of dosimetry systems that will provide adequate informations in the event of a criticality accident. The previous two studies were held at the Valduc Centre near Dijon (France) in June 1970 and at the ORNL in Oak Ridge (USA), in May 1971. Parts of the intercomparison studies were coordination meetings. The topics and conclusions of the Third coordination meeting are given in the Chairman's Report of F.F. Haywood. This paper will deal, therefore, only with data concerning the Third intercomparison experiments in which the RB reactor at Vinca was used as a source of mixed radiation. (author)

  7. Evaluation of radionuclide calibrators and scintigraphic cameras used in nuclear medicine in the Sergipe

    International Nuclear Information System (INIS)

    Lima Ferreira, F.C.; Nascimento Souza, D. do

    2008-01-01

    A quality control program to nuclear medicine services concerns the verification of the efficiency of equipment used to diagnosis and treatment, allow the professional improvement. In this study were assessed the performance of two radionuclide calibrators (activimeters) and of two scintigraphic cameras employed in nuclear medicine in the state of Sergipe, Brazil, according to regulation CNEN -NN-3.05. Additionally, to the radionuclide calibrators it was established a nd characterized an intercomparison of activities measured by different practitioners from standard samples of sealed radioactive sources of 133 Ba and 57 Co. The evaluation of this manufacture object was made thought quality control tests on scintigraphic cameras, such as: test of spatial resolution, tomographic resolution and linearity. The results of the quality control tests were satisfactory and they one can be used as parameter in future evaluations. (author)

  8. 1982 radon intercomparison exercises at EML

    International Nuclear Information System (INIS)

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

    1983-03-01

    This report summarizes the results of two radon measurement intercomparison exercises held in 1982. Sixteen organizations, including five United States federal departments, two state governments, two national laboratories, three universities, three private sector laboratories and Swedish National Institute participated in these exercises. The results indicate good agreement among the participants at the 30 pCi 222 Rn/L level. With the continued interest and cooperation of groups involved in radon measurements, twp intercomparison exercises are planned during 1983

  9. Intercomparison of Rn-222 determination from groundwater

    DEFF Research Database (Denmark)

    Vesterbacka, P.; Pettersson, H.; Hanste, U.-M.

    2010-01-01

    An intercomparison exercise on Rn-222 determination in groundwater was organized between eight Nordic laboratories. The individual laboratory results were in most cases within 20% of the median value and within reported uncertainties. Considering the particular difficulties in preparing, transpor......An intercomparison exercise on Rn-222 determination in groundwater was organized between eight Nordic laboratories. The individual laboratory results were in most cases within 20% of the median value and within reported uncertainties. Considering the particular difficulties in preparing...

  10. Program for Climate Model Diagnosis and Intercomparison

    Data.gov (United States)

    Federal Laboratory Consortium — PCMDI was established in 1989 at the Lawrence Livermore National Laboratory (LLNL), located in the San Francisco Bay area, in California. Our staff includes research...

  11. Description of the XXXIV ARCAL Project Repairing and calibration of electrometers and ionization chambers used in radiotherapy

    International Nuclear Information System (INIS)

    Cruz E, P.; Villaverde L, A.

    2002-01-01

    The technological tools from what the humanity has for the illnesses diagnosis and the cancer treatment, are based in great extent in the use of ionizing radiations. This situation worries to the International Atomic Energy Agency (IAEA), which has implemented technical cooperation programs for protecting the human health. In Latin America the ARCAL program (Regional Agreement of Cooperation for Promotion of Nuclear Science and Technology in Latina America and the Caribbean was created. The Project ARCAL XXXIV has as objective to establish three regional centers of repairing, maintenance and electric calibration of clinical dosemeters, equipment made up for an ionization chamber and an electrometer which is used in radiotherapy to generate calibration procedures, personnel training, establishment of an intercomparison net for the electrometers control used as standards and designing current intensity sources which serve as work standards for each one of the participant countries, Mexico is one of them. (Author)

  12. Intercomparison of different instruments for measuring radon concentration in air

    International Nuclear Information System (INIS)

    Shimo, Michikuni; Iida, Takao

    1990-01-01

    An intercomparison of different instruments for measurement of radon concentration was carried out. The instruments include an ionization chamber, the charcoal-trap method, a flow-type ionization chamber (pulse-counting method), a two-filter method, an electrostatic collection method and a passive integration radon monitor. All instruments except for the passive radon monitor have been calibrated independently. Measurements were performed over a concentration range from about 3.5 Bq·m -3 (in outdoor air) to 110 Bq·m -3 (in indoor air). The results obtained by these techniques, except the two-filter technique, are comparable. Radon daughter concentration measured using a filter-sampling method was about 52% of radon concentration. (author)

  13. Intercomparison of different instruments that measure radon concentration in air

    International Nuclear Information System (INIS)

    Shimo, M.; Iida, T.; Ikebe, Y.

    1987-01-01

    An intercomparison of different instruments for measurement of radon concentration was carried out. The instruments include an ionization chamber, the charcoal-trap technique, a flow-type ionization chamber (pulse-counting technique), a two-filter method, an electrostatic collection method and a passive integrating radon monitor. All instruments except for the passive radon monitor have been calibrated independently. Measurements were performed over a concentration range from about 3.5 Bq/m/sup 3/ (in outdoor air) to 110 Bq/m/sup 3/ (in indoor air). The results obtained from these techniques, except the two-filter technique, are comparable. Radon daughter concentration measured using a filter-sampling technique was about 52% of radon concentrations

  14. International intercomparison of environmental dosimeters under field and laboratory conditions

    International Nuclear Information System (INIS)

    Gesell, T.F.; de Planque Burke, G.; Becker, K.

    1975-04-01

    Based on the results of a pilot study at ORNL in 1973, a more comprehensive international intercomparison of integrating dosimeters for the assessment of external penetrating environmental radiation fields was carried out. Forty-one laboratories from eleven countries participated in this study. A total of 56 sets of six detectors each were mailed to and from Houston, Texas, where they were exposed for three months (July to September 1974) as follows: two in an unprotected space out-of-doors 1 m above ground; two in an air-conditioned shielded area with a known, low exposure rate; and two with the second group, but with an additional exposure to 30 mR. Evaluation of the dosimeters provides information on the calibration precision, the accuracy of field measurement, and transit exposure. Results are discussed. (U.S.)

  15. Precision intercomparison of beam current monitors at CEBAF

    International Nuclear Information System (INIS)

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

    1995-01-01

    The CEBAF accelerator delivers a CW electron beam at fundamental 1497 MHz, with average beam current up to 200 μA. 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

  16. The Community Intercomparison Suite (CIS)

    Science.gov (United States)

    Watson-Parris, Duncan; Schutgens, Nick; Cook, Nick; Kipling, Zak; Kershaw, Phil; Gryspeerdt, Ed; Lawrence, Bryan; Stier, Philip

    2017-04-01

    Earth observations (both remote and in-situ) create vast amounts of data providing invaluable constraints for the climate science community. Efficient exploitation of these complex and highly heterogeneous datasets has been limited however by the lack of suitable software tools, particularly for comparison of gridded and ungridded data, thus reducing scientific productivity. CIS (http://cistools.net) is an open-source, command line tool and Python library which allows the straight-forward quantitative analysis, intercomparison and visualisation of remote sensing, in-situ and model data. The CIS can read gridded and ungridded remote sensing, in-situ and model data - and many other data sources 'out-of-the-box', such as ESA Aerosol and Cloud CCI product, MODIS, Cloud CCI, Cloudsat, AERONET. Perhaps most importantly however CIS also employs a modular plugin architecture to allow for the reading of limitless different data types. Users are able to write their own plugins for reading the data sources which they are familiar with, and share them within the community, allowing all to benefit from their expertise. To enable the intercomparison of this data the CIS provides a number of operations including: the aggregation of ungridded and gridded datasets to coarser representations using a number of different built in averaging kernels; the subsetting of data to reduce its extent or dimensionality; the co-location of two distinct datasets onto a single set of co-ordinates; the visualisation of the input or output data through a number of different plots and graphs; the evaluation of arbitrary mathematical expressions against any number of datasets; and a number of other supporting functions such as a statistical comparison of two co-located datasets. These operations can be performed efficiently on local machines or large computing clusters - and is already available on the JASMIN computing facility. A case-study using the GASSP collection of in-situ aerosol observations

  17. Forward Model Studies of Water Vapor Using Scanning Microwave Radiometers, Global Positioning System, and Radiosondes during the Cloudiness Intercomparison Experiment

    International Nuclear Information System (INIS)

    Mattioli, Vinia; Westwater, Ed R.; Gutman, S.; Morris, Victor R.

    2005-01-01

    Brightness temperatures computed from five absorption models and radiosonde observations were analyzed by comparing them with measurements from three microwave radiometers at 23.8 and 31.4 GHz. Data were obtained during the Cloudiness Inter-Comparison experiment at the U.S. Department of Energy's Atmospheric Radiation Measurement Program's (ARM) site in North-Central Oklahoma in 2003. The radiometers were calibrated using two procedures, the so-called instantaneous ?tipcal? method and an automatic self-calibration algorithm. Measurements from the radiometers were in agreement, with less than a 0.4-K difference during clear skies, when the instantaneous method was applied. Brightness temperatures from the radiometer and the radiosonde showed an agreement of less than 0.55 K when the most recent absorption models were considered. Precipitable water vapor (PWV) computed from the radiometers were also compared to the PWV derived from a Global Positioning System station that operates at the ARM site. The instruments agree to within 0.1 cm in PWV retrieval

  18. Intercomparison of techniques for inspection and diagnostics of heavy water reactor pressure tubes. Additional information

    International Nuclear Information System (INIS)

    2009-03-01

    The reports from Argentina, Canada, India, Korea and Romania are presented concerning the projects carried out under the Coordinated Research Program (CRP) I3.30.10 of the International Agency for Atomic Energy - Vienna related to 'Intercomparison of Techniques for Pressure Tube Inspection and Diagnostics'

  19. API testing program - calibration of microprocessor based flowmeters for integrated metering systems

    Energy Technology Data Exchange (ETDEWEB)

    Elliot, Kenneth D. [Omni Flow Computers, Inc., Stafford, TX (United States)

    2005-07-01

    Microprocessor based flowmeter technologies for liquids, such as Coriolis mass meters, and Ultrasonic flowmeters hold great promise. These technologies offer many advantages, such as no rotating parts, self-diagnostic checks, which can help anticipate and warn of impending failures before they have a major impact on the measurement. These meters are substantially different though than other primary devices due to their heavy reliance on the accompanying secondary electronics. One method to prove that they are accurate would be proving the flowmeter, using a pipe prover or small volume prover (SVP), but these proving methods are designed to count 'real time' pulses from a turbine or PD meter between a known volume, they are not designed to count 'time delayed' 'manufactured pulses' from a microprocessor. There are limitations of the manufactured pulse train and it affects the ability of the flowmeter to be proved using current proving technology. The author of this paper, a chairman of an American Petroleum Institute working group, investigated how the 'microprocessor generated pulses' produced by these types of flowmeters, interacted with the existing measurement technologies in use today. Several microprocessor based flowmeter technologies have been tested, including; Ultrasonic, Coriolis, and Helical Turbine with pulse multiplying preamplifier. Wherever possible, flowmeters of various sizes, and from several vendors have been tested. A significant amount of data has been collected which sheds light into why these types of flowmeters are sometimes difficult to prove. This paper describes the API testing program, and the methodology behind it. It presents results and findings, and offers specific recommendations that may eventually be incorporated into API documents and/or standards in the future. (author)

  20. Regional inter-comparison of measurements of personal dose equivalent Hp(10) using photon beams

    International Nuclear Information System (INIS)

    Bero, M.; Zahili, M.; Kharita, M.H.

    2012-11-01

    The overall objective is to verify performance and to improve the Individual Monitoring services (IMS). This can be achieved with the following specific objectives of the intercomparison:1. To assess the capabilities of the dosimetry services to measure the quantity H p (10) in photon (gamma and x-ray) fields. 2. To help the participating Member States in achieving sufficiently accurate dosimetry service and, if necessary, 3. To provide guidelines for improvements and not simply a test of the performance of the existing dosimetric service. Actually a significant improvement has been achieved by the participants in the accuracy of evaluating personal dose equivalent from 15% in the first phase to 5% in the second phase. Some participants used the results of the inter-comparison to verify the calibration and to improve their dosimetric procedures, but from the results it was clear that some participants need to a technical support especially in calibration and using their measuring system in the field of personal monitoring. The conclusion contains advises, solutions, propositions and evaluation for all situations which noticed during the intercomparison. (authors)

  1. Intercomparison of Terrestrial Laser Scanning Instruments for Assessing Forested Ecosystems: A Brisbane Field Experiment

    Science.gov (United States)

    Armston, J.; Newnham, G.; Strahler, A. H.; Schaaf, C.; Danson, M.; Gaulton, R.; Zhang, Z.; Disney, M.; Sparrow, B.; Phinn, S. R.; Schaefer, M.; Burt, A.; Counter, S.; Erb, A.; Goodwin, N.; Hancock, S.; Howe, G.; Johansen, K.; Li, Z.; Lollback, G.; Martel, J.; Muir, J.; Paynter, I.; Saenz, E.; Scarth, P.; Tindall, D.; Walker, L.; Witte, C.; Woodgate, W.; Wu, S.

    2013-12-01

    During 28th July - 3rd August, 2013, an international group of researchers brought five terrestrial laser scanners (TLS) to long-term monitoring plots in three eucalyptus-dominated woodland sites near Brisbane, Queensland, Australia, to acquire scans at common locations for calibration and intercomparison.They included: DWEL - a dual-wavelength full-waveform laser scanner (Boston U., U. Massachusetts Lowell, U. Massachusetts Boston, USA) SALCA - a dual-wavelength full-waveform laser scanner (U. Salford, UK) CBL - a canopy biomass lidar, a small ultraportable low-cost multiple discrete return scanner (U. Massachusetts Boston, USA) Riegl VZ400 - a survey-grade commercial waveform scanner (Queensland Government and TERN, U. Queensland, Australia) FARO Focus 3D - a lightweight commercial phase-shift ranging laser scanner (U. Southern Queensland) Two plots were scanned at Karawatha Forest Park, a Terrestrial Ecosystem Research Network (TERN) Supersite, and one plot at D'Aguilar National Park. At each 50 x 100 m plot, a center scan point was surrounded by four scan points located 25 m away in a cross pattern allowing for 3-D reconstructions of scan sites in the form of point clouds. At several center points, multiple instrument configurations (i.e. different beam divergence, angular resolution, pulse rate) were acquired to test the impact of instrument specifications on separation of woody and non-woody materials and estimation of vegetation structure parameters. Three-dimensional Photopoint photographic panoramas were also acquired, providing reconstructions of stems in the form of point clouds using photogrammetric correlation methods. Calibrated reflectance targets were also scanned to compare instrument geometric and radiometric performance. Ancillary data included hemispherical photos, TRAC LAI/clumping measurements, spectra of leaves, bark, litter, and other target components. Wet and dry leaf weights determined water content. Planned intercomparison topics and

  2. ERRICCA radon model intercomparison exercise

    International Nuclear Information System (INIS)

    Andersen, C.E.; Albarracin, D.; Csige, I.; Graaf, E.R. van der; Jiranek, M.; Rehs, B.; Svoboda, Z.; Toro, L.

    1999-04-01

    Numerical models based on finite-difference or finite-element methods are used by various research groups in studies of radon-222 transport through soil and building materials. Applications range from design of radon remediation systems to more fundamental studies of radon transport. To ascertain that results obtained with these models are of good quality, it is necessary that such models are tested. This document reports on a benchmark test organized by the EU project ERRICCA: European Research into Radon in Construction Concerted Action. The test comprises the following cases: 1) Steady-state diffusive radon profiles in dry and wet soils, 2) steady-state entry of soil gas and radon into a house, 3) time-dependent radon exhalation from a building-material sample. These cases cover features such as: soil heterogeneity, anisotropy, 3D-effects, time dependency, combined advective and diffusive transport of radon, flux calculations, and partitioning of radon between air and water in soil pores. Seven groups participated in the intercomparison. All groups submitted results without knowing the results of others. For these results, relatively large group-to-group discrepancies were observed. Because of this, all groups scrutinized their computations (once more) and engaged in follow-up discussions with others. During this debugging process, problems were indeed identified (and eliminated). The accordingly revised results were in better agreement than those reported initially. Some discrepancies, however, still remain. All in all, it seems that the exercise has served its purpose and stimulated improvements relating to the quality of numerical modelling of radon transport. To maintain a high quality of modelling, it is recommended that additional exercises are carried out. (au)

  3. Intercomparison of PIXE spectrometry software packages

    International Nuclear Information System (INIS)

    2003-02-01

    During the year 2000, an exercise was organized to make a intercomparison of widely available software packages for analysis of particle induced X ray emission (PIXE) spectra. This TECDOC describes the method used in this intercomparison exercise and presents the results obtained. It also gives a general overview of the participating software packages. This includes basic information on their user interface, graphical presentation capabilities, physical phenomena taken in account, way of presenting results, etc. No recommendation for a particular software package or method for spectrum analysis is given. It is intended that the readers reach their own conclusions and make their own choices, according to their specific needs. This TECDOC will be useful to anyone involved in PIXE spectrum analysis. This TECDOC includes a companion CD with the complete set of test spectra used for intercomparison. The test spectra on this CD can be used to test any PIXE spectral analysis software package

  4. Intercomparison exercises - a 'must' or a 'need'

    International Nuclear Information System (INIS)

    Paraschiva, Mircea-Valentin; Cherestes, Margareta; Cherestes, Codrut

    2011-01-01

    The national legislation and the IAEA's Basic Safety Standards Series require the implementation of a QA programme for approval of dosimetry services. The implementation of a quality system according to EN ISO/IEC17025:2005 standard is a way to demonstrate that the dosimetry service is technically competent and capable of generating technically valid results. There are around fifty different standards relevant to individual monitoring, which indicates the complexity and difficulty of understanding and using the appropriate standard in routine work. The new recommendations published by European Commission - RP-160 - bring together requirements and guidance given in 96/29/EURATOM Directive, ICRP Publications, ICRU Reports and IAEA technical documents. The aim of these recommendations is to address the growing need for improvement and harmonization of practices and procedures used in individual dosimetry, for a mutual recognition of dose assessments performed by Approved Dosimetry Services across Europe. An intercomparison exercise among dosimetry services is like a performance test. The results of intercomparisons are published but anonimized. In many Member States participation in international intercomparisons is strongly recommended as results can be used to support an application for approval or accreditation. In this paper we present the results of our participation in two intercomparison exercises: EURADOS Intercomparison 2008 and EURADOS Intercomparison 2010. The results are displayed using the 'trumpet curves' (ISO 14146). The corrective actions are presented and also the lessons learned. At first exercise, in 2008, we have participated with one dosimetric system - photographic dosemeter - and at the second one, we have participated with two dosimetric systems: photographic and thermoluminescent. (authors)

  5. Status of Photovoltaic Calibration and Measurement Standards

    Science.gov (United States)

    Baraona, Cosmo; Bailey, Sheila; Curtis, Henry; Brinker, David; Jenkins, Phillip; Scheiman, David

    2001-01-01

    The 7th International Workshop on Space Solar Cell Calibration and Measurement was held on September 25-27, 2000 in Girdwood, Alaska. Representatives from eight countries discussed international standards for single and multijunction solar cell measurement and calibration methods, round robin intercomparisons, and irradiation test methods for space solar cells. Progress toward adoption of an ISO standard on single junction cells was made. Agreement was reached to begin work on new standards for multijunction cells and irradiation testing. Progress on present single junction round robin measurements was discussed and future multijunction round robins were planned. The next workshop will be held in Germany in October 2001.

  6. EURADOS intercomparison 2012 for neutron dosemeters

    International Nuclear Information System (INIS)

    Fantuzzi, E.; Chevallier, M.A.; Cruz-Suarez, R.; Luszik-Bhadra, M.; Mayer, S.; Thomas, D.J.; Tanner, R.; Vanhavere, F.

    2014-11-01

    EURADOS, within the work performed by Working Group 2 - Harmonization of Individual Monitoring in Europe, has started a self-sustained programme of regular intercomparisons and has successfully executed three intercomparisons for whole body photon dosemeters (IC2008, IC2010, IC2012) and one intercomparison for extremity dosemeters for photon and beta fields (IC2009). In 2012, the EURADOS intercomparison IC2012n was launched for personal neutron dosemeters routinely used to measure personal dose equivalent, Hp(10), in individual monitoring. No systems under development were allowed to participate. IC2012n was carried out by a EURADOS nominated Organization Group (OG) consisting of: Marie- Anne Chevallier (IRSN, F), Rodolfo Cruz-Suarez (IAEA, UN-Vienna), Marlies Luszik-Bhadra (PTB, D), Sabine Mayer (PSI, CH), David J. Thomas (NPL, UK), Rick Tanner (PHE, UK), Filip Vanhavere (SCK-CEN, B) led by a Coordinator, Elena Fantuzzi (ENEA, I). 31 participants registered for the comparison, with 34 dosimetry systems. In total 816 dosemeters were irradiated in selected neutron fields on an ISO slab phantom. The irradiations were performed at 2 European accredited laboratories which are both National Primary Metrology Laboratories for ionizing radiation: NPL (National Physical Laboratory, UK) and PTB (Physikalisch-Technische Bundesanstalt, D). All irradiations were carried out according to the irradiation plan developed by the OG. The overall results show that most, although not all, dosimetric systems perform acceptably well (within a factor of 2) for irradiations with a bare radionuclide source ( 252 Cf at 0 ), whilst more than half of the systems underestimate the reference value for irradiations from non-normal angles of incidence irradiations ( 252 Cf at 45 ) or for simulated workplace fields ( 252 Cf(D 2 O) or 252 Cf source behind a shadow cone). The performance for 250 keV mono-energetic neutron irradiations varies mainly reflecting the detection principle on which the

  7. EURADOS intercomparison 2012 for neutron dosemeters

    Energy Technology Data Exchange (ETDEWEB)

    Fantuzzi, E. [ENEA-Radiation Protection Institute, Bologna (Italy); Chevallier, M.A. [Institut de Radioprotection et de Surete Nucleaire (IRSN), Fontenay-aux-Roses (France); Cruz-Suarez, R. [International Atomic Energy Agency, Vienna (Austria); Luszik-Bhadra, M. [Physikalisch-Technische Bundesanstalt, Braunschweig (Germany); Mayer, S. [Paul Scherrer Institute (PSI), Villigen (Switzerland); Thomas, D.J. [National Physical Laboratory (NPL), Teddington (United Kingdom); Tanner, R. [Public Health England, Oxon (United Kingdom); Vanhavere, F. [SCK-CEN, Belgian Nuclear Research Centre, Mol (Belgium)

    2014-11-15

    EURADOS, within the work performed by Working Group 2 - Harmonization of Individual Monitoring in Europe, has started a self-sustained programme of regular intercomparisons and has successfully executed three intercomparisons for whole body photon dosemeters (IC2008, IC2010, IC2012) and one intercomparison for extremity dosemeters for photon and beta fields (IC2009). In 2012, the EURADOS intercomparison IC2012n was launched for personal neutron dosemeters routinely used to measure personal dose equivalent, Hp(10), in individual monitoring. No systems under development were allowed to participate. IC2012n was carried out by a EURADOS nominated Organization Group (OG) consisting of: Marie- Anne Chevallier (IRSN, F), Rodolfo Cruz-Suarez (IAEA, UN-Vienna), Marlies Luszik-Bhadra (PTB, D), Sabine Mayer (PSI, CH), David J. Thomas (NPL, UK), Rick Tanner (PHE, UK), Filip Vanhavere (SCK-CEN, B) led by a Coordinator, Elena Fantuzzi (ENEA, I). 31 participants registered for the comparison, with 34 dosimetry systems. In total 816 dosemeters were irradiated in selected neutron fields on an ISO slab phantom. The irradiations were performed at 2 European accredited laboratories which are both National Primary Metrology Laboratories for ionizing radiation: NPL (National Physical Laboratory, UK) and PTB (Physikalisch-Technische Bundesanstalt, D). All irradiations were carried out according to the irradiation plan developed by the OG. The overall results show that most, although not all, dosimetric systems perform acceptably well (within a factor of 2) for irradiations with a bare radionuclide source ({sup 252}Cf at 0 ), whilst more than half of the systems underestimate the reference value for irradiations from non-normal angles of incidence irradiations ({sup 252}Cf at 45 ) or for simulated workplace fields ({sup 252}Cf(D{sub 2}O) or {sup 252}Cf source behind a shadow cone). The performance for 250 keV mono-energetic neutron irradiations varies mainly reflecting the detection

  8. Calibration of the High Resolution Phase Shifter (HRPS) in Linac 3/Rex using a dedicated LabView program

    CERN Document Server

    Winsvold, D

    2013-01-01

    This is a document describing how to calibrate the High Resolution Phase Shifters of Linac 3 and REX. The document also describes how to do tests on the Delay Lines in Linac 2, 3 and REX, but these cannot be calibrated.

  9. Report on the intercomparison for the determination of trace elements in Lake Sediment (SL-1)

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1979-02-01

    The determination of trace element concentrations including those of the rare-earths in geological samples has gained much importance during the past decade. Knowledge of the concentrations of specific elements and of their ratios have proved essential for the understanding of the development of geological strata. With increasing use of instruments in analysis, reference samples have become essential for their calibration and various international organizations have issued reference materials to monitor precision and accuracy in chemical determinations. The IAEA has in the past organized several intercomparisons and prepared reference samples of geochemical materials. The present report deals with a recent intercomparison on the determination of trace elements in Lake Sediment (Sl-1) carried out in 1977-1978 and involving the participation of 43 institutes who returned a total of 2535 individual results on 43 elements.

  10. Calibration uncertainty

    DEFF Research Database (Denmark)

    Heydorn, Kaj; Anglov, Thomas

    2002-01-01

    Methods recommended by the International Standardization Organisation and Eurachem are not satisfactory for the correct estimation of calibration uncertainty. A novel approach is introduced and tested on actual calibration data for the determination of Pb by ICP-AES. The improved calibration...

  11. Intercomparison of JAERI Torso Phantom lung sets

    International Nuclear Information System (INIS)

    Kramer, Gary H.; Hauck, Barry M.

    2000-01-01

    activity homogeneously distributed throughout the tissue substitute material. Many different sources can be used with a single lung set. The coefficients of variation for selected (i.e., those that had three or more values) counting efficiency data at different photon energies show that agreement between lung sets depends on the photon energy. In general, the lower the photon energy the worse the agreement. The 17.7 and 26.4 keV photopeaks show the highest coefficients of variation. This could be due to several factors: the distribution of the radionuclide in the lung insert, the positioning of the detector, the analysis of the photo peak. Once the photon energy rises above 60 keV the coefficient of variation is always less than 6%. This means that 95% of the time one can expect counting efficiencies derived from lung sets that have the activity homogeneously distributed through the tissue substitute material to be within 12% of each other. However, at lower photon energies the agreement is only to within 30%, and this may present a problem for lung intercomparison programs that use low energy emitting photons. (author)

  12. Individual dosimetry and calibration

    International Nuclear Information System (INIS)

    Otto, T.

    1997-01-01

    In 1996, the Dosimetry and Calibration Section was, as in previous years, mainly engaged in routine tasks: the distribution of over 6000 dosimeters (with a total of more than 10,000 films) every two months and the calibration of about 900 fixed and mobile instruments used in the radiation survey sections of RP group. These tasks were, thanks to an experienced team, well mastered. Special efforts had to be made in a number of areas to modernize the service or to keep it in line with new prescriptions. The Individual Dosimetry Service had to assure that CERN's contracting firms comply with the prescriptions in the Radiation Safety Manual (1996) that had been inspired by the Swiss Ordinance of 1994: Companies must file for authorizations with the Swiss Federal Office for Public Health requiring that in every company an 'Expert in Radiation Protection' be nominated and subsequently trained. CERN's Individual Dosimetry Service is accredited by the Swiss Federal Authorities and works closely together with other, similar services on a rigorous quality assurance programme. Within this framework, CERN was mandated to organize this year the annual Swiss 'Intercomparison of Dosimeters'. All ten accredited dosimetry services - among others those of the Paul Scherrer Institute (PSI) in Villigen and of the four Swiss nuclear power stations - sent dosimeters to CERN, where they were irradiated in CERN's calibration facility with precise photon doses. After return to their origin they were processed and evaluated. The results were communicated to CERN and were compared with the originally given doses. A report on the results was subsequently prepared and submitted to the Swiss 'Group of Experts on Personal Dosimetry'. Reference monitors for photon and neutron radiation were brought to standard laboratories to assure the traceability of CERN's calibration service to the fundamental quantities. For photon radiation, a set of ionization chambers was calibrated in the reference field

  13. Analysis of the REAL-84 intercomparison exercise

    International Nuclear Information System (INIS)

    1987-10-01

    The document presents the conclusions and the recommendations of the specialists' meeting organized by the IAEA and held in Jackson Hole (USA) between 27-29 May 1987 as a result of the analysis of the REAL-84 intercomparison exercise for improving the accuracy in radiation damage predictions in the neutron environment using good quality input data and proper calculation methods. 6 refs

  14. Revised VESCAL: Vessel calibration data analysis program. Improvement of a model for non-linear parts of annular and slab tanks

    International Nuclear Information System (INIS)

    Yanagisawa, Hiroshi

    1995-05-01

    For the purpose of the nuclear material accountancy and control for NUCEF: the Nuclear Fuel Cycle Safety Engineering Research Facility, the vessel calibration data analysis program: VESCAL is revised, and a new model for non-linear parts of annular and slab tanks is added to the program. The new model has three unknown parameters, and liquid level is expressed as a square root function with respect to liquid volume. Using the new model, an accurate calibration function on the level and volume data for non-linear parts of annular and slab tanks can be obtained with the smaller number of unknown parameters, compared with a polynomial function model. As a result of benchmark tests for this revision, it was proved that numerical results computed with VESCAL well agreed with those by a statistical analysis program package which is widely used. In addition, the new model would be useful for carrying out data analyses on the vessel calibration at the other bulk handling facilities as well as at NUCEF. This paper describes summary of the program, computational methods and results of benchmark tests concerning this revision. (author)

  15. Result of the intercomparison exercise on radon measuring instruments and radon detectors 'bev- radon ring 2005'

    Energy Technology Data Exchange (ETDEWEB)

    Baumgartner, A. [Vienna Univ. of Technology, Atominstitut, Wien (Austria); Maringer, F.J.; Michai, P.; Kreuziger, M. [BEV-Federal Office of Metrology and Surveying, Wien (Austria)

    2006-07-01

    In spring 2005 the Federal Office of Metrology and Surveying (B.E.V.) invited all in Austria working radon measuring institutes to an intercomparison exercise at the radon calibration laboratory in the Arsenal. The aim of this intercomparison was on the one hand an objective inquiry and documentation of the current metrological potential on the section of radon measurement in Austria - both quantitative and qualitative- and on the other hand an initiative for the participating laboratories to optimize and improve their applied calibration-, measurement and analyse technique. Ten contacted Austrian radon laboratories were prepared to participate on the radon intercomparison exercise. The intercomparison exercise was carried out from 14. till 29. June at the radon calibration laboratory in the Arsenal of the B.E.V.. As radon emanation source a five stepped arranged, at the Arsenal built radon source was used. The source ( A.D.O.T.T.O. 1 is filled with a certified Ra- 226-standard solution of the Czech Metrological Institute (C.M.I.), Prag. A simple statistic based model was used for the evaluation and assessment of the results from the participants, which consider the statistic nature of the radioactive decay combined uncertainty. Altogether 183 measuring instruments participated the intercomparison exercise. Two reference measuring instruments, 22 active and 159 passive measuring instruments. The active measuring instruments formed 6 types of instruments and as passive radon detectors were 7 different types used from the participants. The positioning of the radon measuring instruments and detectors in the radon calibration laboratory was executed in regard to statistic points of view. From the active measuring instruments 17 could qualify and from the passive methods six from eight participants were in compliance to the given criteria. Radon measurements, which could have financial and economics relating implications (e.g. architectural redevelopment or

  16. The second EURADOS intercomparison of national network systems used to provide early warning of a nuclear accident

    International Nuclear Information System (INIS)

    Saez-Vergara, J. C.; Thompson, I. M. G.; Gurriaran, R.; Dombrowski, H.; Funck, E.; Neumaier, S.

    2007-01-01

    In 1999 and 2002, the EURADOS Working Group on Environmental Monitoring organised two European intercomparison exercises of national network systems used to provide early warning in case of a nuclear accident. In total, 12 European countries, represented by more than 40 scientists, participated in these two intercomparisons with more than 35 different dose rate detectors. In addition, an in situ gamma spectrometry intercomparison was performed by a group of European scientists during the 2002 exercise. Results of these spectrometry measurements will be reported elsewhere. This report summarises the results of the second intercomparison, performed in 2002, at the environmental dosimetry facilities of the Physikalisch-Technische Bundesanstalt (PTB) in Germany. The unique combination of the ultra-low background Underground Laboratory (UDO) and two free-field sites (a floating platform on a lake showing an almost pure cosmic radiation field and a free-field gamma ray irradiation facility) provide the particular opportunity to precisely quantify the inherent background of the detectors and to calibrate them almost free of any background and traceable to PTB's primary standards. In addition, the intercomparison comprised investigations on the energy and dose rate dependence of the detectors' response to gamma radiation as well as on the response to cosmic radiation. Finally, the sensitivity of the detector systems to small dose rate variations, similar to that caused by a passing overhead radioactive plume, was studied under realistic free-field conditions. Following the Council Directive 96/29/EURATOM, the participants of the 2002 intercomparison were asked to report their results in terms of the operational quantity ambient dose equivalent, H*(10). Although the verification of the individual calibrations showed smaller discrepancies than those in the 1999 intercomparison, in a few cases, these discrepancies would be still unacceptably high in the case of a real

  17. Low-Level Waste Drum Assay Intercomparison Study

    International Nuclear Information System (INIS)

    Greutzmacher, K.; Kuzminski, J.; Myers, S. C.

    2003-01-01

    Nuclear waste assay is an integral element of programs such as safeguards, waste management, and waste disposal. The majority of nuclear waste is packaged in drums and analyzed by various nondestructive assay (NDA) techniques to identify and quantify the radioactive content. Due to various regulations and the public interest in nuclear issues, the analytical results are required to be of high quality and supported by a rigorous Quality Assurance (QA) program. A valuable QA tool is an intercomparison program in which a known sample is analyzed by a number of different facilities. While transuranic waste (TRU) certified NDA teams are evaluated through the Performance Demonstration Program (PDP), low-level waste (LLW) assay specialists have not been afforded a similar opportunity. NDA specialists from throughout the DOE complex were invited to participate in this voluntary drum assay intercomparison study that was organized and facilitated by the Solid Waste Operations and the Safeguards Science and Technology groups at the Los Alamos National Laboratory and by Eberline Services. Each participating NDA team performed six replicate blind measurements of two 55-gallon drums with relatively low-density matrices (a 19.1 kg shredded paper matrix and a 54.4 kg mixed metal, rubber, paper and plastic matrix). This paper presents the results from this study, with an emphasis on discussing the lessons learned as well as desirable follow up programs for the future. The results will discuss the accuracy and precision of the replicate measurements for each NDA team as well as any issues that arose during the effort

  18. Calibration factor or calibration coefficient?

    International Nuclear Information System (INIS)

    Meghzifene, A.; Shortt, K.R.

    2002-01-01

    Full text: The IAEA/WHO network of SSDLs was set up in order to establish links between SSDL members and the international measurement system. At the end of 2001, there were 73 network members in 63 Member States. The SSDL network members provide calibration services to end-users at the national or regional level. The results of the calibrations are summarized in a document called calibration report or calibration certificate. The IAEA has been using the term calibration certificate and will continue using the same terminology. The most important information in a calibration certificate is a list of calibration factors and their related uncertainties that apply to the calibrated instrument for the well-defined irradiation and ambient conditions. The IAEA has recently decided to change the term calibration factor to calibration coefficient, to be fully in line with ISO [ISO 31-0], which recommends the use of the term coefficient when it links two quantities A and B (equation 1) that have different dimensions. The term factor should only be used for k when it is used to link the terms A and B that have the same dimensions A=k.B. However, in a typical calibration, an ion chamber is calibrated in terms of a physical quantity such as air kerma, dose to water, ambient dose equivalent, etc. If the chamber is calibrated together with its electrometer, then the calibration refers to the physical quantity to be measured per electrometer unit reading. In this case, the terms referred have different dimensions. The adoption by the Agency of the term coefficient to express the results of calibrations is consistent with the 'International vocabulary of basic and general terms in metrology' prepared jointly by the BIPM, IEC, ISO, OIML and other organizations. The BIPM has changed from factor to coefficient. The authors believe that this is more than just a matter of semantics and recommend that the SSDL network members adopt this change in terminology. (author)

  19. Reproducibility in cyclostratigraphy: initiating an intercomparison project

    Science.gov (United States)

    Sinnesael, Matthias; De Vleeschouwer, David; Zeeden, Christian; Claeys, Philippe

    2017-04-01

    The study of astronomical climate forcing and the application of cyclostratigraphy have experienced a spectacular growth over the last decades. In the field of cyclostratigraphy a broad range in methodological approaches exist. However, comparative study between the different approaches is lacking. Different cases demand different approaches, but with the growing importance of the field, questions arise about reproducibility, uncertainties and standardization of results. The radioisotopic dating community, in particular, has done far-reaching efforts to improve reproducibility and intercomparison of radioisotopic dates and their errors. To satisfy this need in cyclostratigraphy, we initiate a comparable framework for the community. The aims are to investigate and quantify reproducibility of, and uncertainties related to cyclostratigraphic studies and to provide a platform to discuss the merits and pitfalls of different methodologies, and their applicabilities. With this poster, we ask the feedback from the community on how to design this comparative framework in a useful, meaningful and productive manner. In parallel, we would like to discuss how reproducibility should be tested and what uncertainties should stand for in cyclostratigraphy. On the other hand, we intend to trigger interest for a cyclostratigraphic intercomparison project. This intercomparison project would imply the analysis of artificial and genuine geological records by individual researchers. All participants would be free to determine their method of choice. However, a handful of criterions will be required for an outcome to be comparable. The different results would be compared (e.g. during a workshop or a special session), and the lessons learned from the comparison could potentially be reported in a review paper. The aim of an intercomparison project is not to rank the different methods according to their merits, but to get insight into which specific methods are most suitable for which

  20. Calibration/validation strategy for GOES-R L1b data products

    Science.gov (United States)

    Fulbright, Jon P.; Kline, Elizabeth; Pogorzala, David; MacKenzie, Wayne; Williams, Ryan; Mozer, Kathryn; Carter, Dawn; Race, Randall; Sims, Jamese; Seybold, Matthew

    2016-10-01

    The Geostationary Operational Environmental Satellite-R series (GOES-R) will be the next generation of NOAA geostationary environmental satellites. The first satellite in the series is planned for launch in November 2016. The satellite will carry six instruments dedicated to the study of the Earth's weather, lightning mapping, solar observations, and space weather monitoring. Each of the six instruments require specialized calibration plans to achieve their product quality requirements. In this talk we will describe the overall on-orbit calibration program and data product release schedule of the GOES-R program, as well as an overview of the strategies of the individual instrument science teams. The Advanced Baseline Imager (ABI) is the primary Earth-viewing weather imaging instrument on GOES-R. Compared to the present on-orbit GOES imagers, ABI will provide three times the spectral bands, four times the spatial resolution, and operate five times faster. The increased data demands and product requirements necessitate an aggressive and innovative calibration campaign. The Geostationary Lightning Mapper (GLM) will provide continuous rapid lightning detection information covering the Americas and nearby ocean regions. The frequency of lightning activity points to the intensification of storms and may improve tornado warning lead time. The calibration of GLM will involve intercomparisons with ground-based lightning detectors, an airborne field campaign, and a ground-based laser beacon campaign. GOES-R also carries four instruments dedicated to the study of the space environment. The Solar Ultraviolet Imager (SUVI) and the Extreme Ultraviolet and X-Ray Irradiance Sensors (EXIS) will study solar activity that may affect power grids, communication, and spaceflight. The Space Environment In-Situ Suite (SEISS) and the Magnetometer (MAG) study the in-situ space weather environment. These instruments follow a calibration and validation (cal/val) program that relies on

  1. The GERDA calibration system

    Energy Technology Data Exchange (ETDEWEB)

    Baudis, Laura; Froborg, Francis; Tarka, Michael; Bruch, Tobias; Ferella, Alfredo [Physik-Institut, Universitaet Zuerich (Switzerland); Collaboration: GERDA-Collaboration

    2012-07-01

    A system with three identical custom made units is used for the energy calibration of the GERDA Ge diodes. To perform a calibration the {sup 228}Th sources are lowered from the parking positions at the top of the cryostat. Their positions are measured by two independent modules. One, the incremental encoder, counts the holes in the perforated steel band holding the sources, the other measures the drive shaft's angular position even if not powered. The system can be controlled remotely by a Labview program. The calibration data is analyzed by an iterative calibration algorithm determining the calibration functions for different energy reconstruction algorithms and the resolution of several peaks in the {sup 228}Th spectrum is determined. A Monte Carlo simulation using the GERDA simulation software MAGE has been performed to determine the background induced by the sources in the parking positions.

  2. Intercomparison of fog water samplers

    Science.gov (United States)

    Schell, Dieter; Georgii, Hans-Walter; Maser, Rolf; Jaeschke, Wolfgang; Arends, Beate G.; Kos, Gerard P. A.; Winkler, Peter; Schneider, Thomas; Berner, Axel; Kruisz, Christian

    1992-11-01

    During the Po Valley Fog Experiment 1989, two fogwater collectors were operated simultaneously at the ground and the results were compared to each other. The chemical analyses of the samples as well as the collection efficiencies showed remarkable differences between both collectors. Some differences in the solute concentrations in the samples of both collectors could be expected due to small differences in the 50-percent cut-off diameters. The large differences in the collection efficiencies however cannot be explained by these small variations of d sub 50, because normally only a small fraction of the water mass is concentrated in the size range of 5-7-micron droplets. It is shown that it is not sufficient to characterize a fogwater collector only by its cut-off diameter. The results of several wind tunnel calibration tests show that the collection efficiencies of the fogwater collectors are a function of windspeed and shape of the droplet spectra.

  3. Quantitative determination of bone mineral content (QCT) - intercomparison of computer tomographs of the same construction

    International Nuclear Information System (INIS)

    Andresen, R.; Banzer, D.; Felsenberg, D.; Wolf, K.J.

    1994-01-01

    An intercomparison of 4 CT scanners of the same manufacturer was performed. The bone mineral content of 11 lumbar vertebral columns removed directly post mortem was determined in a specially constructed lucite-water phantom. Even devices of the same construction were shown to yield a variation in the quantitative evaluation markedly exceeding the annual physiological mineral loss. As long as scanner adjustment by physical calibration phantoms has not yet been established, a course assessment and therapy control of bone mineral content should always be carried out on the same QCT scanner. (orig.) [de

  4. Environmental radioactivity measurement intercomparison exercise 1990

    International Nuclear Information System (INIS)

    Jerome, S.M.

    1991-05-01

    In a recent national intercomparison exercise, 49 laboratories involved in making environmental radioactivity measurements took part in the analysis of samples supplied by the National Physical Laboratory (NPL) in the United Kingdom. There were two sets of samples; one containing pure β-emitters and one containing β/γ-emitters. Two thirds of the participants measured the β/γ-emitter sample only, the remainder measured both. The results are presented. (author)

  5. Atmospheric Correction Inter-Comparison Exercise

    Directory of Open Access Journals (Sweden)

    Georgia Doxani

    2018-02-01

    Full Text Available The Atmospheric Correction Inter-comparison eXercise (ACIX is an international initiative with the aim to analyse the Surface Reflectance (SR products of various state-of-the-art atmospheric correction (AC processors. The Aerosol Optical Thickness (AOT and Water Vapour (WV are also examined in ACIX as additional outputs of AC processing. In this paper, the general ACIX framework is discussed; special mention is made of the motivation to initiate the experiment, the inter-comparison protocol, and the principal results. ACIX is free and open and every developer was welcome to participate. Eventually, 12 participants applied their approaches to various Landsat-8 and Sentinel-2 image datasets acquired over sites around the world. The current results diverge depending on the sensors, products, and sites, indicating their strengths and weaknesses. Indeed, this first implementation of processor inter-comparison was proven to be a good lesson for the developers to learn the advantages and limitations of their approaches. Various algorithm improvements are expected, if not already implemented, and the enhanced performances are yet to be assessed in future ACIX experiments.

  6. Mobile Radiological Laboratories Intercomparison Measurements - Chernobyl

    International Nuclear Information System (INIS)

    Martincic, R.; Glavic-Cindro, D.; Korun, M.; Pucelj, B.; Vodenik, B.

    2001-01-01

    Full text: In last decade different institutions in European countries have organised periodic intercomparison exercises of mobile radiological laboratories to improve the preparedness of emergency monitoring teams. The 12th Regular Workshop on Mobile Radiological Laboratories was held in Exclusion Zone of the Chernobyl NPP, Ukraine from September 13 to September 18, 1999 under the acronym MORAL-12. The European Centre of Technological Safety (TESEC), Kiev, Ukraine and J. Stefan Institute, Ljubljana, Slovenia organised Intercomparison Measurements 99 jointly under the auspices of the International Atomic Energy Agency (IAEA). Nineteen teams from 9 countries and IAEA participated in the Workshop. Six field and personal and equipment contamination control exercises were prepared and conducted at two measuring sites with very different ambient dose rate levels. The Workshop pointed out that such exercises are very valuable for rapid, efficient and harmonised emergency response in case of nuclear or radiological emergency. The teams had an opportunity to test their ability to perform field measurements in the contaminated environment, and to report results on the spot, as well as to test their emergency preparedness and persistence. They gained new experiences for fieldwork under stress conditions. An overview and results of these intercomparison measurements are presented and lessons learned are discussed. (author)

  7. Intercomparison campaign of Contracted Partner Institutes 1997

    International Nuclear Information System (INIS)

    Reinen, H.A.J.M.; Tijsmans, M.H.; Van Tuinen, S.T.; Overwater, R.M.W.; Aldenkamp, F.J.

    1998-01-01

    The Dutch National Plan for Nuclear Emergency Planning and Response (EPR) is trained frequently. Intercomparison campaigns and exercises are part of this training for the Contracted Partner Institutes (CPI). The results of an intercomparison campaign in 1997 for the CPI are reported. Two carbon cartridges, one contaminated homogeneously and one inhomogeneously with 131 I, and a water sample contaminated with 134 Cs and 137 Cs were analysed by means of gamma spectroscopy. The results had to be faxed to RIVM within the time limits prescribed in the emergency protocols for CPI, i.e. 2 hours for the cartridges and 24 hours for the water sample. Most CPI reported in time. The results for the inhomogeneously contaminated cartridge are within 25% from the accepted reference value (ARV). For the homogeneously contaminated cartridge the results are within 40% from the ARV. In reality, the contamination of the cartridge will have an exponential profile, with most of the activity in the first few millimeters. In this situation results can be expected to be within 20% from the true value. The results for the water sample are within 5% from the ARV. Although most CPI have applied corrections for coincidence summing for 134 Cs there is still a systematic error of 4% for this nuclide. In regard of the requirements for measurements during emergency situations, the results of this intercomparison campaign are satisfactory

  8. On the methodology of the intercomparison of TND evaluations

    International Nuclear Information System (INIS)

    Yiftah, S.; Caner, M.; Gur, Y.

    1979-03-01

    The paper presents the problems which arise when two independent complete nuclear data evaluations of the same nuclide are available. A detailed intercomparison of the evaluations can be a multi-levelled exercise of considerable detail, the stages of which cannot always be performed. However, a detailed intercomparison can be a rich source for improving considerably the nuclear data used for the different applications. Preliminary examples of intercomparison are given for illustrative purpose. (B.G.)

  9. MoDOT pavement preservation research program volume VII, re-calibration of triggers and performance models.

    Science.gov (United States)

    2015-10-01

    The objective of this task is to develop the concept and framework for a procedure to routinely create, re-calibrate, and update the : Trigger Tables and Performance Models. The scope of work for Task 6 includes a limited review of the recent pavemen...

  10. GEO-LEO reflectance band inter-comparison with BRDF and atmospheric scattering corrections

    Science.gov (United States)

    Chang, Tiejun; Xiong, Xiaoxiong Jack; Keller, Graziela; Wu, Xiangqian

    2017-09-01

    The inter-comparison of the reflective solar bands between the instruments onboard a geostationary orbit satellite and onboard a low Earth orbit satellite is very helpful to assess their calibration consistency. GOES-R was launched on November 19, 2016 and Himawari 8 was launched October 7, 2014. Unlike the previous GOES instruments, the Advanced Baseline Imager on GOES-16 (GOES-R became GOES-16 after November 29 when it reached orbit) and the Advanced Himawari Imager (AHI) on Himawari 8 have onboard calibrators for the reflective solar bands. The assessment of calibration is important for their product quality enhancement. MODIS and VIIRS, with their stringent calibration requirements and excellent on-orbit calibration performance, provide good references. The simultaneous nadir overpass (SNO) and ray-matching are widely used inter-comparison methods for reflective solar bands. In this work, the inter-comparisons are performed over a pseudo-invariant target. The use of stable and uniform calibration sites provides comparison with appropriate reflectance level, accurate adjustment for band spectral coverage difference, reduction of impact from pixel mismatching, and consistency of BRDF and atmospheric correction. The site in this work is a desert site in Australia (latitude -29.0 South; longitude 139.8 East). Due to the difference in solar and view angles, two corrections are applied to have comparable measurements. The first is the atmospheric scattering correction. The satellite sensor measurements are top of atmosphere reflectance. The scattering, especially Rayleigh scattering, should be removed allowing the ground reflectance to be derived. Secondly, the angle differences magnify the BRDF effect. The ground reflectance should be corrected to have comparable measurements. The atmospheric correction is performed using a vector version of the Second Simulation of a Satellite Signal in the Solar Spectrum modeling and BRDF correction is performed using a semi

  11. A calibration facility for radon fluxmeter

    International Nuclear Information System (INIS)

    Li Xianjie; Qiu Shoukang; Zhou Jianliang; Liu Chunkui; Pan Jialin; Yang Mingli

    1998-01-01

    Calibration facilities for radon fluxmeter with three kinds of different emanation medium have been developed. The stability of radon flux is 5%, 9% (RSD) respectively. The uniformity of radon flux is 4.5%, 8.5% (RSD) respectively. These specifications fulfill the calibration requirement for radon fluxmeter. The determination of radon flux of facility takes full account of eliminating the main error source-attenuation effect (including leakage and back diffusion etc.): not only prevent attenuation and make a relevant correction. Therefore the accuracy of determination is assured. The calibration, intercomparison of radon flux meter and the quantitatively evaluation on the measurement method of radon flux are made to be possible by the successful establishment of this facility. (author)

  12. Calibration of Nuclear Track Detectors

    International Nuclear Information System (INIS)

    Vukovic, J.B; Antanasijevic, R.; Novakovic, V.; Tasic, M.

    1998-01-01

    In this work we compare some of our preliminary results relating to the calibration Nuclear Track Detectors (NTD) with corresponding results obtained from other participants at the First International Intercomparison of Image Analyzers (III 97/98). Thirteen laboratories from Algeria, China, Czech Rep., France. Germany, Greece, Hungary, India, Italy, Mexico, Saudi Arabia, Slovenia and Yugoslavia participated in the III A 97/98. The NTD was 'Tustrack', Bristol. This type of CR-39 detector was etched by the organizer (J.Paltarey of al, Atomic Energy Research Institute, HPD, Budapest, Hungary). Etching condition was: 6N NaOH, 70 0C . Seven series detectors were exposed with the sources: B(n,a)Li, Am-241, Pu-Be(n,p), Radon and Am-Cm-Pu. Following parameters of exposed detectors were measured: track density of different sorts of tracks (circular, elliptical, track overlapping, their diameters, major and minor axis and other). (authors)

  13. Inter-comparison of GRACE data over India

    Science.gov (United States)

    Banerjee, Chandan; Kumar, D. Nagesh

    2016-05-01

    The advent of satellite remote sensing and its use in hydrology has facilitated a huge leap in the understanding of the various water resources, its interaction with ecological systems and anthropogenic creations. Recently, NASA and German Aerospace Research Agency-DLR launched the Gravity Recovery and Climate Experiment (GRACE) satellite mission consisting of two satellites. They measure the time varying gravity which gives changes in the distribution of mass on the surface of the earth which after removing atmospheric and oceanic effects is majorly caused by changes in Terrestrial Water Storage (TWS) changes. GRACE data is generally available as spherical harmonic coefficients, which is difficult for hydrologists to understand and interpret. JPL's TELLUS website is now providing gridded global data set in the form of mass anomaly derived from the Level-2 data sets of spherical harmonic coefficients of 3 sources, viz. CSR, GFZ and JPL. Before using these data sets for solving hydrological problems, it is important to understand the differences and similarities between these data sets as direct calibration of GRACE data is not possible. In this study we do an inter-comparison of the Level-3 Release 05 data sets over India. We compare the data sets using Pearson, Spearman and Kendall correlation. CSR and GFZ data sets appear to be closest to each other whereas JPL and GFZ data sets are most different from each other.

  14. Syringe shape and positioning relative to efficiency volume inside dose calibrators and its role in nuclear medicine quality assurance programs

    International Nuclear Information System (INIS)

    Santos, J.A.M.; Carrasco, M.F.; Lencart, J.; Bastos, A.L.

    2009-01-01

    A careful analysis of geometry and source positioning influence in the activity measurement outcome of a nuclear medicine dose calibrator is presented for 99m Tc. The implementation of a quasi-point source apparent activity curve measurement is proposed for an accurate correction of the activity inside several syringes, and compared with a theoretical geometric efficiency model. Additionally, new geometrical parameters are proposed to test and verify the correct positioning of the syringes as part of acceptance testing and quality control procedures.

  15. Liquid Krypton Calorimeter Calibration Software

    CERN Document Server

    Hughes, Christina Lindsay

    2013-01-01

    Calibration of the liquid krypton calorimeter (LKr) of the NA62 experiment is managed by a set of standalone programs, or an online calibration driver. These programs are similar to those used by NA48, but have been updated to utilize classes and translated to C++ while maintaining a common functionality. A set of classes developed to handle communication with hardware was used to develop the three standalone programs as well as the main driver program for online calibration between bursts. The main calibration driver has been designed to respond to run control commands and receive burst data, both transmitted via DIM. In order to facilitate the process of reading in calibration parameters, a serializable class has been introduced, allowing the replacement of standard text files with XML configuration files.

  16. Intercomparison of analysis methods for seismically isolated nuclear structures. Papers and working materials presented at the 3. research coordination meeting

    International Nuclear Information System (INIS)

    1998-01-01

    The Coordinated research program on Intercomparison of analysis methods for seismically isolated nuclear structures involved participants from Italy, Japan, Republic of Korea, Russia, United Kingdom, USA, EC. The purpose of the meeting was to review the progress on the finite element prediction of the force-deformation behaviour of seismic isolators and to discuss the first set of analytical results for the prediction of the response of base-oscillated structures to earthquake inputs. The intercomparison of predictions of bearing behaviour has identified important unexpected issues requiring deeper investigation

  17. Description of the XXXIV ARCAL Project {sup R}epairing and calibration of electrometers and ionization chambers used in radiotherapy; Descripcion del proyecto ARCAL XXXIV {sup R}eparacion y calibracion de electrometros y camaras de ionizacion utilizados en radioterapia

    Energy Technology Data Exchange (ETDEWEB)

    Cruz E, P.; Villaverde L, A. [Instituto Nacional de Investigaciones Nucleares, A.P. 18-1027, 11801 Mexico D.F. (Mexico)

    2002-07-01

    The technological tools from what the humanity has for the illnesses diagnosis and the cancer treatment, are based in great extent in the use of ionizing radiations. This situation worries to the International Atomic Energy Agency (IAEA), which has implemented technical cooperation programs for protecting the human health. In Latin America the ARCAL program (Regional Agreement of Cooperation for Promotion of Nuclear Science and Technology in Latina America and the Caribbean was created. The Project ARCAL XXXIV has as objective to establish three regional centers of repairing, maintenance and electric calibration of clinical dosemeters, equipment made up for an ionization chamber and an electrometer which is used in radiotherapy to generate calibration procedures, personnel training, establishment of an intercomparison net for the electrometers control used as standards and designing current intensity sources which serve as work standards for each one of the participant countries, Mexico is one of them. (Author)

  18. The ARM-GCSS Intercomparison Study of Single-Column Models and Cloud System Models

    International Nuclear Information System (INIS)

    Cederwall, R.T.; Rodriques, D.J.; Krueger, S.K.; Randall, D.A.

    1999-01-01

    The Single-Column Model (SCM) Working Group (WC) and the Cloud Working Group (CWG) in the Atmospheric Radiation Measurement (ARM) Program have begun a collaboration with the GEWEX Cloud System Study (GCSS) WGs. The forcing data sets derived from the special ARM radiosonde measurements made during the SCM Intensive Observation Periods (IOPs), the wealth of cloud and related data sets collected by the ARM Program, and the ARM infrastructure support of the SCM WG are of great value to GCSS. In return, GCSS brings the efforts of an international group of cloud system modelers to bear on ARM data sets and ARM-related scientific questions. The first major activity of the ARM-GCSS collaboration is a model intercomparison study involving SCMs and cloud system models (CSMs), also known as cloud-resolving or cloud-ensemble models. The SCM methodologies developed in the ARM Program have matured to the point where an intercomparison will help identify the strengths and weaknesses of various approaches. CSM simulations will bring much additional information about clouds to evaluate cloud parameterizations used in the SCMs. CSMs and SCMs have been compared successfully in previous GCSS intercomparison studies for tropical conditions. The ARM Southern Great Plains (SGP) site offers an opportunity for GCSS to test their models in continental, mid-latitude conditions. The Summer 1997 SCM IOP has been chosen since it provides a wide range of summertime weather events that will be a challenging test of these models

  19. EURADOS intercomparison exercise on Monte Carlo modelling of a medical linear accelerator.

    Science.gov (United States)

    Caccia, Barbara; Le Roy, Maïwenn; Blideanu, Valentin; Andenna, Claudio; Arun, Chairmadurai; Czarnecki, Damian; El Bardouni, Tarek; Gschwind, Régine; Huot, Nicolas; Martin, Eric; Zink, Klemens; Zoubair, Mariam; Price, Robert; de Carlan, Loïc

    2017-01-01

    In radiotherapy, Monte Carlo (MC) methods are considered a gold standard to calculate accurate dose distributions, particularly in heterogeneous tissues. EURADOS organized an international comparison with six participants applying different MC models to a real medical linear accelerator and to one homogeneous and four heterogeneous dosimetric phantoms. The aim of this exercise was to identify, by comparison of different MC models with a complete experimental dataset, critical aspects useful for MC users to build and calibrate a simulation and perform a dosimetric analysis. Results show on average a good agreement between simulated and experimental data. However, some significant differences have been observed especially in presence of heterogeneities. Moreover, the results are critically dependent on the different choices of the initial electron source parameters. This intercomparison allowed the participants to identify some critical issues in MC modelling of a medical linear accelerator. Therefore, the complete experimental dataset assembled for this intercomparison will be available to all the MC users, thus providing them an opportunity to build and calibrate a model for a real medical linear accelerator.

  20. O papel dos programas interlaboratoriais para a qualidade dos resultados analíticos Interlaboratorial programs for improving the quality of analytical results

    Directory of Open Access Journals (Sweden)

    Queenie Siu Hang Chui

    2004-12-01

    Full Text Available Interlaboratorial programs are conducted for a number of purposes: to identify problems related to the calibration of instruments, to assess the degree of equivalence of analytical results among several laboratories, to attribute quantity values and its uncertainties in the development of a certified reference material and to verify the performance of laboratories as in proficiency testing, a key quality assurance technique, which is sometimes used in conjunction with accreditation. Several statistics tools are employed to assess the analytical results of laboratories participating in an intercomparison program. Among them are the z-score technique, the elypse of confidence and the Grubbs and Cochran test. This work presents the experience in coordinating an intercomparison exercise in order to determine Ca, Al, Fe, Ti and Mn, as impurities in samples of silicon metal of chemical grade prepared as a candidate for reference material.

  1. Atmospheric Correction Inter-comparison Exercise (ACIX)

    Science.gov (United States)

    Vermote, E.; Doxani, G.; Gascon, F.; Roger, J. C.; Skakun, S.

    2017-12-01

    The free and open data access policy to Landsat-8 (L-8) and Sentinel-2 (S-2) satellite imagery has encouraged the development of atmospheric correction (AC) approaches for generating Bottom-of-Atmosphere (BOA) products. Several entities have started to generate (or plan to generate in the short term) BOA reflectance products at global scale for L-8 and S-2 missions. To this end, the European Space Agency (ESA) and National Aeronautics and Space Administration (NASA) have initiated an exercise on the inter-comparison of the available AC processors. The results of the exercise are expected to point out the strengths and weaknesses, as well as communalities and discrepancies of various AC processors, in order to suggest and define ways for their further improvement. In particular, 11 atmospheric processors from five different countries participate in ACIX with the aim to inter-compare their performance when applied to L-8 and S-2 data. All the processors should be operational without requiring parametrization when applied on different areas. A protocol describing in details the inter-comparison metrics and the test dataset based on the AERONET sites has been agreed unanimously during the 1st ACIX workshop in June 2016. In particular, a basic and an advanced run of each of the processor were requested in the frame of ACIX, with the aim to draw robust and reliable conclusions on the processors' performance. The protocol also describes the comparison metrics of the aerosol optical thickness and water vapour products of the processors with the corresponding AERONET measurements. Moreover, concerning the surface reflectances, the inter-comparison among the processors is defined, as well as the comparison with the MODIS surface reflectance and with a reference surface reflectance product. Such a reference product will be obtained using the AERONET characterization of the aerosol (size distribution and refractive indices) and an accurate radiative transfer code. The inter-comparison

  2. Intercomparison of radiation dosimeters for individual monitoring

    International Nuclear Information System (INIS)

    1993-05-01

    The Co-ordinated Research Programme on Intercomparison for Individual Monitoring was established to provide participants with an opportunity to assess (1) their ability to measure external photon radiation fields and (2) the potential impact of introduction of the new operational quantities on their dosimetry programmes. Twenty-four laboratories from 18 IAEA Member States and three international organizations, including the IAEA, participated. The results of phase II of the CRP are presented in this document, which includes a compilation of the presentations and conclusions from the meeting. Refs, figs and tabs

  3. Single Particle Soot Photometer intercomparison at the AIDA chamber

    Directory of Open Access Journals (Sweden)

    M. Laborde

    2012-12-01

    Full Text Available Soot particles, consisting of black carbon (BC, organic carbon (OC, inorganic salts, and trace elements, are emitted into the atmosphere during incomplete combustion. Accurate measurements of atmospheric BC are important as BC particles cause adverse health effects and impact the climate.

    Unfortunately, the accurate measurement of the properties and mass concentrations of BC particles remains difficult. The Single Particle Soot Photometer (SP2 can contribute to improving this situation by measuring the mass of refractory BC in individual particles as well as its mixing state.

    Here, the results of the first detailed SP2 intercomparison, involving 6 SP2s from 6 different research groups, are presented, including the most evolved data products that can presently be calculated from SP2 measurements.

    It was shown that a detection efficiency of almost 100% down to 1 fg BC per particle can readily be achieved, and that this limit can be pushed down to ∼0.2 fg BC with optimal SP2 setup. Number and mass size distributions of BC cores agreed within ±5% and ±10%, respectively, in between the SP2s, with larger deviations in the range below 1 fg BC.

    The accuracy of the SP2's mass concentration measurement depends on the calibration material chosen. The SP2 has previously been shown to be equally sensitive to fullerene soot and ambient BC from sources where fossil fuel was dominant and less sensitive to fullerene soot than to Aquadag. Fullerene soot was therefore chosen as the standard calibration material by the SP2 user community; however, many data sets rely solely on Aquadag calibration measurements. The difference in SP2 sensitivity was found to be almost equal (fullerene soot to Aquadag response ratio of ∼0.75 at 8.9 fg BC for all SP2s. This allows the calculation of a fullerene soot equivalent calibration curve from a measured Aquadag calibration, when no fullerene soot calibration is available. It could be

  4. Syringe shape and positioning relative to efficiency volume inside dose calibrators and its role in nuclear medicine quality assurance programs

    Energy Technology Data Exchange (ETDEWEB)

    Santos, J.A.M. [Servico de Fisica Medica, Instituto Portugues de Oncologia do Porto Francisco Gentil, E.P.E., Rua Dr. Antonio Bernardino de Almeida, 4200072 Porto (Portugal); Centro de Investigacao, Instituto Portugues de Oncologia do Porto Francisco Gentil, E.P.E., Rua Dr. Antonio Bernardino de Almeida, 4200072 Porto (Portugal)], E-mail: a.miranda@portugalmail.pt; Carrasco, M.F. [Servico de Fisica Medica, Instituto Portugues de Oncologia do Porto Francisco Gentil, E.P.E., Rua Dr. Antonio Bernardino de Almeida, 4200072 Porto (Portugal); Centro de Investigacao, Instituto Portugues de Oncologia do Porto Francisco Gentil, E.P.E., Rua Dr. Antonio Bernardino de Almeida, 4200072 Porto (Portugal); Lencart, J. [Servico de Fisica Medica, Instituto Portugues de Oncologia do Porto Francisco Gentil, E.P.E., Rua Dr. Antonio Bernardino de Almeida, 4200072 Porto (Portugal); Bastos, A.L. [Servico de Medicina Nuclear, Instituto Portugues de Oncologia do Porto Francisco Gentil, E.P.E., Rua Dr. Antonio Bernardino de Almeida, 4200072 Porto (Portugal)

    2009-06-15

    A careful analysis of geometry and source positioning influence in the activity measurement outcome of a nuclear medicine dose calibrator is presented for {sup 99m}Tc. The implementation of a quasi-point source apparent activity curve measurement is proposed for an accurate correction of the activity inside several syringes, and compared with a theoretical geometric efficiency model. Additionally, new geometrical parameters are proposed to test and verify the correct positioning of the syringes as part of acceptance testing and quality control procedures.

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

    International Nuclear Information System (INIS)

    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

  6. Thematic network on the analysis of thorium and its isotopes in workplace materials. Report on the 2nd intercomparison exercise

    International Nuclear Information System (INIS)

    Howe, A.; White, M.

    2000-12-01

    Work Package 2 (WP 2) of the EC Thematic Network on ''The analysis of thorium and its isotopes in workplace materials'' is concerned with ''Examination and comparison of analytical techniques for the determination of thorium and its progeny in bulk materials and the development of standards, both for the calibration of associated metrological facilities, and for routine quality control purposes''. The primary objective of WP 2 is ''To evaluate appropriate techniques and determine best practice for analysis of 232 Th at workplace levels and environments'', and is to be achieved through a series of intercomparison exercises. Following the results of the 1st intercomparison exercise, a 2nd intercomparison exercise was designed to evaluate the capability of the analytical methods currently being used by European laboratories to determine thorium at very low levels in the presence of a complex inorganic matrix. The intercomparison exercise involved the analysis of three samples of thorium in solution, prepared by the United Kingdom National Physical Laboratory. One sample was the equilibrium solution, analysed in the 1st intercomparison exercise. The other two samples were prepared by dilution of a non-equilibrium thorium solution, one of which was spiked with impurity elements. (i) The results showed a further improvement in the accuracy of measurements in the equilibrium solution, when compared with the results from the 1st intercomparison study. There was an overall drop in u-test values and the number of u-test values above the upper limit of significance fell from 6 to 3. (ii) Overall, participating laboratories also performed well in the analysis of the low level non-equilibrium solutions. However, several laboratories using y-spectrometry had insufficient sensitivity for measurement of low level non-equilibrium sample solutions and did not report results. (iii) There was little evidence that the presence of impurities had a detrimental effect on measurements made

  7. Preliminary report: STOIC CGCM intercomparison - equatorial sections

    International Nuclear Information System (INIS)

    Davey, M; Huddleston, M; Sperber, K R.

    1999-01-01

    An intercomparison and assessment of the tropical behaviour of coupled general circulation models (CGCMs) is being carried out, to identify common strengths and weaknesses and thus guide future CGCM development. The work is being carried out as part of the CLIVAR climate research programme, as a WG-SIP (Working Group on Seasonal to Interannual Prediction) project called STOIC (Study of Tropical Oceans In CGCMs), organised by Michael Davey. This project complements a companion sub-project called ENSIP (El Ni no Simulation Intercomparison Project) organised by Mojib Latif (Max- Planck-Institute for Meteorology) that focusses on equatorial Pacific CGCM behaviour (Latif et al. 1999). Previous coupled model assessments (Mechoso et al. 1995, Neelin et al. 1992, and ENSIP) have focussed on tropical Pacific behaviour. The aim of STOIC is to look at model performance in all tropical ocean regions. This status report contains a sample of the STOIC assessment work, highlighting mean and inter- annual equatorial sea surface temperatures and zonal windstresses. The intention is to submit STOIC and ENSIP papers in mid-1999 for publication together in a refereed journal

  8. Summary of 'IAEA intercomparison of IBA software'

    International Nuclear Information System (INIS)

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

    2008-01-01

    The International Atomic Energy Agency has sponsored a formal intercomparison exercise for the seven depth profiling ion beam analysis codes, which are: GISA, RUMP, RBX, DEPTH, DataFurnace, SIMNRA and MCERD. This intercomparison is published in Nucl. Instr. and Meth. B [N.P. Barradas, K. Arstila, G. Battistig, M. Bianconi, N. Dytlewski, C. Jeynes, E. Kotai, G. Lulli, M. Mayer, E. Rauhala, E. Szilagyi, M. Thompson, Nucl. Instr. and Meth. B 262 (2007) 281-303] and summarised here. The codes implement all known physical effects and they are all evaluated. We demonstrate that there is agreement between codes often better than 0.1%; and also detailed agreement with real spectra, showing in particular that the SRIM 2003 stopping powers for Si are correct to 0.6% for 1.5 MeV He. For the case of heavy ion elastic recoil detection (HI-ERD) the single scattering codes performed poorly for scattered particles, although recoiled particles were calculated correctly

  9. UK laboratory intercomparison on internal dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Speed, J.; Birchall, A.; Bull, R.; Cockerill, R.; Jarvis, N.S.; Marsh, J.W.; Peace, M.S.; Roberts, G.; Scarlett, C.; Spencer, D.; Stewart, P

    2003-07-01

    A laboratory intercomparison for internal dose assessment from a variety of intake scenarios is described. This is the first UK intercomparison using the revised ICRP Human Respiratory Tract and biokinetic models. Four United Kingdom laboratories participated and six cases were assessed. Overall, the agreement in internal dose assessments between laboratories was considered satisfactory with 79% of the assessed committed effective doses, e(50), for cases within a band of {+-}40% of the median value. The range (highest/lowest) in e(50) estimated by the laboratories was smallest (1.2) for a case involving inhalation of {sup 137}Cs. The range was greatest (6.0) for a case involving a wound with, and possible inhalation of, {sup 238}Pu, {sup 239}Pu and {sup 241}Am; the variation between laboratories in assessment of intakes could not be considered to be satisfactory in this case. Judgements on the most appropriate data to use in estimating intakes, choice of parameter values for use with the ICRP models and allowing for the effects of treatment with DTPA were important sources of variability between laboratories. (author)

  10. Thorium in the workplace measurement intercomparison

    International Nuclear Information System (INIS)

    Modna, D.K.; Jerome, S.M.; White, M.A.; Woods, M.J.

    2000-01-01

    The monitoring of radionuclides in the nuclear industry has been recognized as the most straightforward way of assessing health and safety issues associated with the exposure of the workforce to potentially harmful radiation doses. Much of this is achieved by measurements in the workplace itself and by the bioassay and monitoring of workers in the industry. However, there also exists a significant 'non-nuclear' industry where workers are exposed to radioactive materials, for example where this involves thorium, which is made wide use of in the aerospace and other high technology industries. As such work involves the processing of thorium bearing materials, the workforce is potentially exposed to 232 Th and its daughter nuclides. Thus, to monitor the workforce effectively, it is important to be able to measure both 232 Th and the decay products of 232 Th where they are in an unknown state of radioactive equilibrium and this is where monitoring laboratories may experience some difficulty. Accordingly, the Health and Safety Laboratory in the UK has organized a EC wide project on the monitoring of thorium in the 'non-nuclear' workplace; this project is currently ongoing. We report the results of the first intercomparison of this project involving two solutions of 232 Th, one in radioactive equilibrium and one not in equilibrium with its daughters. The results are presented with some comments on how this intercomparison has progressed and how these first results will inform the rest of the project

  11. Research and calibration projects

    International Nuclear Information System (INIS)

    1988-01-01

    The NAC (National Accelerator Centre), South Africa, has been involved in neutron dosimetry intercomparison studies at the Universite Catholique de Louvain, Belgium (UCL), and at the MRC Cyclotron Unit, Clatterbridge Hospital, U.K. A reciprocal visit was paid to the NAC by UCL personnel in order to undertake both dosimetry and radiobiological intercomparison studies. Only the physical dosimetry intercomparison measurements undertaken with tissue equivalent ionization chambers have been analysed. Measurements were also made with Geiger-Mueller counters in order to derive the gamma dose component in the neutron beam, but analyses are not yet complete. 6 figs., 19 refs., 5 tabs

  12. Instrumentation calibration

    International Nuclear Information System (INIS)

    Mack, D.A.

    1976-08-01

    Procedures for the calibration of different types of laboratory equipment are described. Provisions for maintaining the integrity of reference and working standards traceable back to a national standard are discussed. Methods of validation and certification methods are included. An appendix lists available publications and services of national standardizing agencies

  13. National intercomparison program applied to water radionuclide analysis in SEAMB - CRCN/NE, Brazil; Programa nacional de intercomparação aplicado a análises de radionuclídeos em água no SEAMB - CRCN/NE

    Energy Technology Data Exchange (ETDEWEB)

    Bastos, Thiago M. R.; Santos, Thiago O.; Neto, Alberto P.; Farias, Emerson E. G.; Filho, Crescêncio A. S.; França, Elvis J. De, E-mail: thiagomrbastos@gmail.com, E-mail: thiago_cbufpe@yahoo.com.br, E-mail: nibbering4@gmail.com, E-mail: emersonemiliano@yahoo.com.br, E-mail: candrade@cnen.gov.br, E-mail: ejfranca@cnen.gov.br [Centro Regional de Ciências Nucleares do Nordeste (CRCN-NE/CNEN-PE), Recife, PE (Brazil)

    2017-07-01

    Water is essential for mankind in its most diverse uses and an evaluation of its quality is necessary, especially when used for human consumption. The Brazilian Ministry of Health established through the Ordinance 36 in 1990 the standards and norms of water potability, and among the parameters to be monitored are the concentrations of activities present in the water bodies. Given the importance of water as one of the main ways of exposure to natural radionuclide emissions due to its frequent ingestion, by providing man with higher natural radiation doses than those normally received by terrestrial radiation, it is necessary the continuous radiological control of waters used for consumption. The existence of laboratories that have certified quality in the analysis of these radioisotopes in water is essential and for this, programs have been created that seek to integrate the results of analysis of environmental samples of water for the determination of radionuclides at the national level, such as the National Intercomparison Program (PNI), promoted by the Institute of Radioprotection and Dosimetry (IRD) of which the Regional Nuclear Science Center of the Northeast (CRCN-NE) is a member since 2011. Until the year 2016, were reported to IRD, the program manager, for statistical evaluation and for analytical performance, 17 analyzes that presented average values of 1,67BqL{sup -1} for {sup 60}Co, 3,712 Bq L{sup -1} for {sup 65}Zn, 7,812 Bq L{sup -1} for {sup 1}'0{sup 6}Ru, 3,06 Bq L{sup -1} for {sup 133}Ba, 1,19 Bq L{sup -1} for the {sup 134}Cs and 1,50 Bq L{sup -1} for the {sup 137}Cs. These analysis were reported by the PNI, certifying the analytical capacity of the Environmental Monitoring Service of the Regional Center of Nuclear Sciences Northeastern Brazil in the determination of radioisotopes in water by Gamma Spectrometry using Hyperpure Germanium - HPGe detectors.

  14. Evaluation of quality assurance calibration results based on repeated calibrations; Evaluacion del aseguramiento de la calidad de los resultados de calibracion en base a la repeticion de las calibraciones

    Energy Technology Data Exchange (ETDEWEB)

    Mestre de Juan, V.; Albau Albos, J.; Gomez Llobat, L.

    2011-07-01

    To ensure quality assurance of the calibration results, as indicated by the UNE-EN ISO / IEC 17025:2005 in paragraph 5.9, the laboratory has established procedures for quality control of its activity. Thus, the laboratory participates in both inter-laboratory intercomparison exercises, cycle through the entire range of radiation qualities reflected in the scope of its accreditation, such as intra-laboratory intercomparison exercises. In this case, repeat quarterly by two different operators both the calibration of an ionization chamber irradiation of a direct reading personal dosimeter.

  15. The 1996 Radon Intercomparison Exercise at PSI

    International Nuclear Information System (INIS)

    Schuler, C.; Butterweck-Dempewolf, G.

    1997-05-01

    The 1996 Radon Intercomparison Exercise at PSI was organized by the PSI Reference Laboratory for Radon Gas Activity Concentration Measurements. A total of 14 laboratories, companies and institutions participated with radon gas detectors and measuring instruments. The detectors and instruments were exposed in the PSI radon chamber during seven days in a reference atmosphere with an average radon gas concentration of about 6000 Bqm -3 . Comparison of the results of electret ionization chambers, track etch detectors and measuring instruments with the PSI target value showed the criteria for traceability and reproducibility demanded by the Federal Office for Health for the acknowledgement of Swiss Radon Gas Measurement Laboratories to be fulfilled for all participants. Exposure of track etch detectors stored for more than one year demonstrated that this detector type can suffer sensitivity loss by a too long storage period. (author) figs., tabs., refs

  16. Czech results at criticality dosimetry intercomparison 2002.

    Science.gov (United States)

    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.

  17. POLCAL - POLARIMETRIC RADAR CALIBRATION

    Science.gov (United States)

    Vanzyl, J.

    1994-01-01

    Calibration of polarimetric radar systems is a field of research in which great progress has been made over the last few years. POLCAL (Polarimetric Radar Calibration) is a software tool intended to assist in the calibration of Synthetic Aperture Radar (SAR) systems. In particular, POLCAL calibrates Stokes matrix format data produced as the standard product by the NASA/Jet Propulsion Laboratory (JPL) airborne imaging synthetic aperture radar (AIRSAR). POLCAL was designed to be used in conjunction with data collected by the NASA/JPL AIRSAR system. AIRSAR is a multifrequency (6 cm, 24 cm, and 68 cm wavelength), fully polarimetric SAR system which produces 12 x 12 km imagery at 10 m resolution. AIRSTAR was designed as a testbed for NASA's Spaceborne Imaging Radar program. While the images produced after 1991 are thought to be calibrated (phase calibrated, cross-talk removed, channel imbalance removed, and absolutely calibrated), POLCAL can and should still be used to check the accuracy of the calibration and to correct it if necessary. Version 4.0 of POLCAL is an upgrade of POLCAL version 2.0 released to AIRSAR investigators in June, 1990. New options in version 4.0 include automatic absolute calibration of 89/90 data, distributed target analysis, calibration of nearby scenes with calibration parameters from a scene with corner reflectors, altitude or roll angle corrections, and calibration of errors introduced by known topography. Many sources of error can lead to false conclusions about the nature of scatterers on the surface. Errors in the phase relationship between polarization channels result in incorrect synthesis of polarization states. Cross-talk, caused by imperfections in the radar antenna itself, can also lead to error. POLCAL reduces cross-talk and corrects phase calibration without the use of ground calibration equipment. Removing the antenna patterns during SAR processing also forms a very important part of the calibration of SAR data. Errors in the

  18. Identification of irradiated foodstuffs: results of a European test intercomparison

    International Nuclear Information System (INIS)

    Raffi, J.; Belliardo, J.-J.; Agnel, J.-P.; Vincent, P.

    1993-01-01

    The results of an intercomparison, organized by the Community Bureau of Reference (Commission of the European Communities), on the use of Electron Spin Resonance spectroscopy for the identification of irradiated food are presented. A qualitative intercomparison was carried out using beef and trout bones, sardine scales, pistachio nut shells, dried grapes and papaya. Protocols are proposed for meat bones, fish bones (with some restrictions) and fruits such as dried grapes and papaya. The protocol for pistachio nuts and fruits such as strawberries is more complicated and further research is needed prior the organization of future intercomparisons. A quantitative intercomparison on poultry bones was also organized. Laboratories were able to distinguish between chicken bones irradiated at 1 to 3 kGy or 7 to 10 kGy. (author)

  19. Electron spin resonance intercomparison studies on irradiated foodstuffs

    International Nuclear Information System (INIS)

    Raffi, J.

    1992-01-01

    The results of intercomparison studies organized by the Community Bureau of Reference on the use of electron spin resonance spectroscopy for the identification of irradiated food are presented. A qualitative intercomparison was carried out using beef and trout bones, sardine scales, pistachio nut shells, dried grapes and papaya. A quantitative intercomparison involving the use of poultry bones was also organized. There was no difficulty in identifying meat bones, dried grapes and papaya. In the case of fish bones there is a need for further kinetic studies using different fish species. The identification of pistachio nut shells is more complicated and further research is needed prior to the organization of a further intercomparison. Laboratories were able to distinguish between chicken bones irradiated in the range 1 to 3 KGy or 7 to 10 KGy although there was a partial overlap between the results from different laboratories

  20. International NMR-based Environmental Metabolomics Intercomparison Exercise

    Science.gov (United States)

    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...

  1. Electron spin resonance intercomparison studies on irradiated foodstuffs

    Energy Technology Data Exchange (ETDEWEB)

    Raffi, J [CEA Centre d` Etudes de Cadarache, 13 - Saint-Paul-lez-Durance (FR)

    1992-07-01

    The results of intercomparison studies organized by the Community Bureau of Reference on the use of electron spin resonance spectroscopy for the identification of irradiated food are presented. A qualitative intercomparison was carried out using beef and trout bones, sardine scales, pistachio nut shells, dried grapes and papaya. A quantitative intercomparison involving the use of poultry bones was also organized. There was no difficulty in identifying meat bones, dried grapes and papaya. In the case of fish bones there is a need for further kinetic studies using different fish species. The identification of pistachio nut shells is more complicated and further research is needed prior to the organization of a further intercomparison. Laboratories were able to distinguish between chicken bones irradiated in the range 1 to 3 KGy or 7 to 10 KGy although there was a partial overlap between the results from different laboratories.

  2. Intercomparison Measurements Exercises of Mobile Radiological Laboratories (invited paper)

    International Nuclear Information System (INIS)

    Martincic, R.

    2000-01-01

    After the reactor accident in Chernobyl, the importance of mobile radiological laboratories became evident and in situ gamma spectrometry became a common method for the rapid detection of gamma emitters in the environment. Since then different institutions in European countries have organised periodic intercomparison exercises of mobile radiological laboratories to improve the measurement methods and the preparedness of emergency monitoring teams. The general objectives of these workshops are to promote the knowledge and to exchange the experiences of emergency monitoring teams that use mobile radiological laboratories, as well as to foster the international harmonisation of emergency monitoring procedures and cooperation among teams. Finally, the results of intercomparison measurements have shown that such exercises are mandatory for rapid, efficient and correct environmental monitoring in nuclear or radiological emergencies. An overview of these intercomparison measurements is given, results from the 1999 intercomparison workshop are presented and lessons learned are discussed. (author)

  3. Exposure-rate calibration using large-area calibration pads

    International Nuclear Information System (INIS)

    Novak, E.F.

    1988-09-01

    The US Department of Energy (DOE) Office of Remedial Action and Waste Technology established the Technical Measurements Center (TMC) at the DOE Grand Junction Projects Office (GJPO) in Grand Junction, Colorado, to standardize, calibrate, and compare measurements made in support of DOE remedial action programs. A set of large-area, radioelement-enriched concrete pads was constructed by the DOE in 1978 at the Walker Field Airport in Grand Junction for use as calibration standards for airborne gamma-ray spectrometer systems. The use of these pads was investigated by the TMC as potential calibration standards for portable scintillometers employed in measuring gamma-ray exposure rates at Uranium Mill Tailings Remedial Action (UMTRA) project sites. Data acquired on the pads using a pressurized ionization chamber (PIC) and three scintillometers are presented as an illustration of an instrumental calibration. Conclusions and recommended calibration procedures are discussed, based on the results of these data

  4. Intercomparison of radon gas detectors 1999 and 2000 at PSI

    International Nuclear Information System (INIS)

    Schuler, Christoph; Butterweck, Gernot

    2000-10-01

    This report describes the results of two radon intercomparison exercises performed by the Reference Laboratory for Radon Gas Activity Concentration Measurements at Paul Scherrer Institut from Sep 9th to Oct 6th, 1999, and from March 21st to 28th, 2000. Radon gas detectors and instruments were exposed in the PSI Radon Chamber in reference atmospheres to 1060 kBqhm -3 radon gas exposure at an average radon gas concentration of 6400 Bqm -3 and to 2050 kBqhm -3 radon gas exposure at an average radon gas concentration of 12500 Bqm -3 , respectively. These intercomparison exercises determined the performance of electret ionisation chambers, track etch detectors and measuring instruments at high humidity (1999 Intercomparison Exercise) and at a high radon gas exposure (2000 Intercomparison Exercise). In the 1999 Intercomparison Exercise, electret ionisation chambers revealed an influence on high humidity. This effect may be due to impurities on a microscopic scale on the electrets of these detectors. With few exceptions, in both the 1999 and the 2000 Radon Intercomparison Exercise the deviations of the measurement results to the reference radon gas concentration values were less than 15% (traceability criterion) and the standard deviation of the results of five detectors less than 15% (reproducibility criterion). (author) [de

  5. Comprehensive Australasian multicentre dosimetric intercomparison: issues, logistics and recommendations.

    Science.gov (United States)

    Ebert, M A; Harrison, K M; Cornes, D; Howlett, S J; Joseph, D J; Kron, T; Hamilton, C S; Denham, J W

    2009-02-01

    The present paper describes the logistics of the 2004-2008 Australasian Level III Dosimetry Intercomparison. Dosimetric intercomparisons (or 'audits') can be used in radiotherapy to evaluate the accuracy and quality of radiation delivery. An intercomparison was undertaken in New Zealand and Australia to evaluate the feasibility and logistics of ongoing dosimetric intercomparisons that evaluate all steps in the radiotherapy treatment process, known as a 'Level III' intercomparison. The study commenced in 2002 with the establishment of a study team, definition of the study protocol, acquisition of appropriate equipment and recruitment of participating radiotherapy centres. Measurements were undertaken between October 2004 and March 2008, and included collation of data on time, costs and logistics of the study. Forty independent Australian and New Zealand radiotherapy centres agreed to participate. Measurement visits were made to 37 of these centres. Data is presented on the costs of the study and the level of support required. The study involved the participation of 16 staff at the study centre who invested over 4000 hours in the study, and of over 200 professionals at participating centres. Recommendations are provided for future phantom-based intercomparisons. It is hoped that the present paper will be of benefit to any centres or groups contemplating similar activities by identifying the processes involved in establishing the study, the potential hazards and pitfalls, and expected resource requirements.

  6. Calibration of solid state nuclear track detectors at high energy ion beams for cosmic radiation measurements: HAMLET results

    International Nuclear Information System (INIS)

    Szabó, J.; Pálfalvi, J.K.

    2012-01-01

    The MATROSHKA experiments and the related HAMLET project funded by the European Commission aimed to study the dose burden of the crew working on the International Space Station (ISS). During these experiments a human phantom equipped with several thousands of radiation detectors was exposed to cosmic rays inside and outside the ISS. Besides the measurements realized in Earth orbit, the HAMLET project included also a ground-based program of calibration and intercomparison of the different detectors applied by the participating groups using high-energy ion beams. The Space Dosimetry Group of the Centre for Energy Research (formerly Atomic Energy Research Institute) participated in these experiments with passive solid state nuclear track detectors (SSNTDs). The paper presents the results of the calibration experiments performed in the years 2008–2011 at the Heavy Ion Medical Accelerator (HIMAC) of the National Institute of Radiological Sciences (NIRS), Chiba, Japan. The data obtained serve as update and improvement for the previous calibration curves which are necessary for the evaluation of the SSNTDs exposed in unknown space radiation fields.

  7. Calibration of solid state nuclear track detectors at high energy ion beams for cosmic radiation measurements: HAMLET results

    Energy Technology Data Exchange (ETDEWEB)

    Szabo, J., E-mail: julianna.szabo@energia.mta.hu [Hungarian Academy of Sciences, Centre for Energy Research, Konkoly Thege Miklos ut 29-33, 1525 Budapest 114, P.O. Box 49 (Hungary); Palfalvi, J.K. [Hungarian Academy of Sciences, Centre for Energy Research, Konkoly Thege Miklos ut 29-33, 1525 Budapest 114, P.O. Box 49 (Hungary)

    2012-12-01

    The MATROSHKA experiments and the related HAMLET project funded by the European Commission aimed to study the dose burden of the crew working on the International Space Station (ISS). During these experiments a human phantom equipped with several thousands of radiation detectors was exposed to cosmic rays inside and outside the ISS. Besides the measurements realized in Earth orbit, the HAMLET project included also a ground-based program of calibration and intercomparison of the different detectors applied by the participating groups using high-energy ion beams. The Space Dosimetry Group of the Centre for Energy Research (formerly Atomic Energy Research Institute) participated in these experiments with passive solid state nuclear track detectors (SSNTDs). The paper presents the results of the calibration experiments performed in the years 2008-2011 at the Heavy Ion Medical Accelerator (HIMAC) of the National Institute of Radiological Sciences (NIRS), Chiba, Japan. The data obtained serve as update and improvement for the previous calibration curves which are necessary for the evaluation of the SSNTDs exposed in unknown space radiation fields.

  8. Development and implantation of a control and data acquisition program for the calibration of instruments for diagnostic radiology; Desenvolvimento e implantacao de um programa de controle e aquisicao de dados na calibracao de instrumentos em radiodiagnostico

    Energy Technology Data Exchange (ETDEWEB)

    Betti, Flavio

    2007-07-01

    Design techniques of an automatic control system implementing corrected kerma determination and shutter command in the calibration laboratory at IPEN are shown, as well as the periodic calibration program developed for a monitor chamber for several X-ray beam qualities used for diagnostic radiology and radiation protection instruments. Two reference electrometers, a multichannel secondary standard thermometer, and an absolute pressure barometer were connected to the Rs-232 interface from a PC computer equipped with a National Instruments multi function analog and digital I/O card. LabVIEW{sup MR} was chosen as programming tool, which allowed for the development of a suite of programs for both controlling the shutter timing cycles and the calibration of the monitor chamber against a reference standard. A detailed description of the methods used for troubleshooting, fine tuning of parameters and evaluation of program results is followed by an analysis showing that considerable advantages regarding reduction of time and precision improvements during the calibrations could be achieved by the use of the developed programs, particularly under adverse conditions like those found during short expositions, or instead during long irradiation intervals where fluctuation of parameters like kerma rate or room conditions (temperature or pressure) can be found. (author)

  9. INTERCOMPARISON OF RESULTS FOR A PWR ROD EJECTION ACCIDENT

    Energy Technology Data Exchange (ETDEWEB)

    DIAMOND,D.J.; ARONSON,A.; JO,J.; AVVAKUMOV,A.; MALOFEEV,V.; SIDOROV,V.; FERRARESI,P.; GOUIN,C.; ANIEL,S.; ROYER,M.E.

    1999-10-01

    This study is part of an overall program to understand the uncertainty in best-estimate calculations of the local fuel enthalpy during the rod ejection accident. Local fuel enthalpy is used as the acceptance criterion for this design-basis event and can also be used to estimate fuel damage for the purpose of determining radiological consequences. The study used results from neutron kinetics models in PARCS, BARS, and CRONOS2, codes developed in the US, the Russian Federation, and France, respectively. Since BARS uses a heterogeneous representation of the fuel assembly as opposed to the homogeneous representations in PARCS and CRONOS, the effect of the intercomparison was primarily to compare different intra-assembly models. Quantitative comparisons for core power, reactivity, assembly fuel enthalpy and pin power were carried out. In general the agreement between methods was very good providing additional confidence in the codes and providing a starting point for a quantitative assessment of the uncertainty in calculated fuel enthalpy using best-estimate methods.

  10. Nuclear accident dosimetry measurements at third IAEA intercomparison Vinca, Yugoslavia, May 1973

    International Nuclear Information System (INIS)

    Palfalvi, J.; Makra, S.

    1974-09-01

    Nuclear accident dosimeters from several countries were compared in Vinca, Yugoslavia at an IAEA meeting. The Hungarian Central Research Institute for Physics team performed measurements for the dosimetry of a heavy water assembly which has an escape spectrum significantly differing from the escape spectra of the fast reactors used in previous intercomparisons or from the light water systems used in the Institute. Another problem investigated was the influence of minor spectral differences on the dose determined by activation measurement and spectrum fitting. The importance of sophisticated spectrum calculations was proved. The Vinca irradiations were used for the calibration of the albedo dosimeters of the institute, which are currently applied for personal dosimetry. (K.A.)

  11. Spatial inter-comparison of Top-down emission inventories in European urban areas

    Science.gov (United States)

    Trombetti, Marco; Thunis, Philippe; Bessagnet, Bertrand; Clappier, Alain; Couvidat, Florian; Guevara, Marc; Kuenen, Jeroen; López-Aparicio, Susana

    2018-01-01

    This paper presents an inter-comparison of the main Top-down emission inventories currently used for air quality modelling studies at the European level. The comparison is developed for eleven European cities and compares the distribution of emissions of NOx, SO2, VOC and PPM2.5 from the road transport, residential combustion and industry sectors. The analysis shows that substantial differences in terms of total emissions, sectorial emission shares and spatial distribution exist between the datasets. The possible reasons in terms of downscaling approaches and choice of spatial proxies are analysed and recommendations are provided for each inventory in order to work towards the harmonisation of spatial downscaling and proxy calibration, in particular for policy purposes. The proposed methodology may be useful for the development of consistent and harmonised European-wide inventories with the aim of reducing the uncertainties in air quality modelling activities.

  12. Intercomparison of in vivo monitoring systems in Europe. Results from Risoe National Laboratory

    International Nuclear Information System (INIS)

    Lauridsen, B.; Soegaard-Hansen, J.

    1996-12-01

    This report contains the contribution from Risoe National Laboratory to the European project: 'Intercomparison of in Vivo Monitoring Systems in Europe'. The whole-body counter at Risoe and the measurement on a phantom used as an intercalibration object in the project is described. In four case studies, prepared by the project coordinator, intakes of radionuclides and resulting doses are calculated. These calculations are based on informations on the radioactive materials taken into the body, routes of intake and on body contents of radionuclides from simulated single or multiple whole-body measurement. The answer from Risoe National Laboratory to two questionnaires - one on the whole-body counting facility and calibration methods and one on the legal requirements is the country - is listed. (au)

  13. Report on intercomparison IAEA/AG-B-1 of radionuclide measurements in marine algae sample

    International Nuclear Information System (INIS)

    1985-09-01

    This report includes results of the intercomparison exercise organized to enable analysts involved in measurements to check the analytical performance of their measuring methods on homogeneous seaweed material and also to establish reference values for radionuclides 40 K, 54 Mn, 58 Co, 60 Co, 65 Zn, 134 Cs, 137 Cs, 90 Sr, 99 Tc, 238 Pu, 239+240 Pu, 241 Am, 238 U, 230 Th, 226 Ra, 210 Pb, 210 Po, 232 Th, 228 Ra and 228 Th for the advantage of all those who need well-characterized standard material for calibration purposes. The sample of the brown alga Fucus vesiculosus from the coastal area of the Southwest Baltic near the Swedish nuclear plant at Barseback was made available for intercalibration in 47 laboratories in 26 countries. The results were obtained by gamma spectrometry, alpha spectrometry and beta counting

  14. Intercomparison of ionization chambers in standard X-ray beams, at radiotherapy, diagnostic radiology and radioprotection levels

    International Nuclear Information System (INIS)

    Bessa, Ana Carolina Moreira de

    2007-01-01

    Since the calibration of radiation measurement instruments and the knowledge of their major characteristics are very important subjects, several different types of ionization chambers were inter compared in terms of their calibration coefficients and their energy dependence, in radiotherapy, diagnostic radiology and radioprotection standard beams. An intercomparison of radionuclide calibrators for nuclear medicine was performed, using three radionuclides: 67 Ga, 201 Tl and 99m Tc; the results obtained were all within the requirements of the national standard CNEN-NE-3.05. In order to complete the range of radiation qualities of the Calibration Laboratory of IPEN, standard radiation beam qualities, radiation protection and low energy radiation therapy levels, were established, according international recommendations. Three methodologies for the calibration of unsealed ionization chambers in X-ray beams were studied and compared. A set of Victoreen ionization chambers, specially designed for use in laboratorial intercomparisons, was submitted to characterization tests. The performance of these Victoreen ionization chambers showed that they are suitable for use in radioprotection beams, because the results obtained agree with international recommendations. However, these Victoreen ionization chambers can be used in radiotherapy and diagnostic radiology beams only with some considerations, since their performance in these beams, especially in relation to the energy dependence and stabilization time tests, did not agree with the international recommendations for dosimeters used in radiotherapy and diagnostic radiology beams. This work presents data on the performance of several types of ionization chambers in different X-ray beams, that may be useful for choosing the appropriate instrument for measurements in ionizing radiation beams. (author)

  15. Intercomparison of ionization chambers in standard X-ray beams, at radiotherapy, diagnostic radiology and radioprotection levels

    International Nuclear Information System (INIS)

    Bessa, Ana Carolina Moreira de

    2006-01-01

    Since the calibration of radiation measurement instruments and the knowledge of their major characteristics are very important subjects, several different types of ionization chambers were intercompared in terms of their calibration coefficients and their energy dependence, in radiotherapy, diagnostic radiology and radioprotection standard beams. An intercomparison of radionuclide calibrators for nuclear medicine was performed, using three radionuclides: 67 Ga, 201 Tl and 99m Tc; the results obtained were all within the requirements of the national standard CNEN-NE-3.05. In order to complete the range of radiation qualities of the Calibration Laboratory of IPEN, standard radiation beam qualities, radiation protection and low energy radiation therapy levels, were established, according international recommendations. Three methodologies for the calibration of unsealed ionization chambers in X-ray beams were studied and compared. A set of Victoreen ionization chambers, specially designed for use in laboratorial intercomparisons, was submitted to characterization tests. The performance of these Victoreen ionization chambers showed that they are suitable for use in radioprotection beams, because the results obtained agree with international recommendations. However, these Victoreen ionization chambers can be used in radiotherapy and diagnostic radiology beams only with some considerations, since their performance in these beams, especially in relation to the energy dependence and stabilization time tests, did not agree with the international recommendations for dosimeters used in radiotherapy and diagnostic radiology beams. This work presents data on the performance of several types of ionization chambers in different X-ray beams, that may be useful for choosing the appropriate instrument for measurements in ionizing radiation beams. (author)

  16. Intercomparison of Environmental Dosemeters Using Various TL Materials and Dosimetry Systems

    International Nuclear Information System (INIS)

    Crnic, B.; Gobec, S.; Zorko, B.; Knezevic, Z.; Majer, M.; Ranogajec-Komor, M.

    2013-01-01

    The aim of the present work was to compare the ambient dose equivalent (H*(10)) values determined at 20 sites around NPP Krško, using different thermoluminescence (TL) materials and various dosimetry systems. The H*(10) was measured by the CaF 2 :Mn (TLD-400) provided by the Jozef Stefan Institute (JSI) Ljubljana, Slovenia. These dosemeters were deployed in the environment in plastic bags and suspended inside the plastic bottles. On the other hand the Ruder Boskovic Institute (RBI), Zagreb, Croatia applied LiF:Mg,Cu,P (TLD-100H), CaF 2 :Mn, Al 2 O 3 :C TL detectors and radiophotoluminescence (RPL) glass dosemeters type SG1. They were placed at the same locations in as much as possible same conditions as JSI detectors. According to the protocol established for this intercomparison, the control and transport detectors (not deployed in the environment) were held in dark storage containers and used to determine the background radiation. The TL responses were corrected for individual sensitivity of the TL detectors which is an important factor after the calibration irradiations. The calibration irradiations were performed by 137Cs sources provided in Secondary Standard Dosimetry Laboratory facilities at the JSI and RBI. The results obtained by different TL materials and different dosimetry systems show interesting features especially concerning local environmental peculiarities. The H*(10) obtained by the dosemeters of various types deployed in the countryside fluctuate less than 10 %. The outcome should emphasize also in the manner that the results obtained and reported in the intercomparison are traceable to the primary standards.(author)

  17. A dosimetric intercomparison of brachytherapy facilities in Ireland, Scotland and the North of England

    International Nuclear Information System (INIS)

    Heeney, Conor; McClean, Brendan; Kelly, Colin

    2005-01-01

    Background and purpose: A dosimetric intercomparison of brachytherapy remote afterloading units in Ireland, Scotland and the North of England has been carried out involving 9 radiotherapy centres, and sampling 5 HDR and 6 LDR units. Materials and methods: Absolute calibrations have been performed in air on both HDR and LDR sources. The results are expressed in terms of a ratio of local to calibrated value. Frequency distributions were obtained for the multi-source LDR units by individually measuring each source. Using these distributions the effect of non-uniform source strength on the dose rate at Manchester point A was assessed for a typical clinical brachytherapy insertion for carcinoma of the cervix. Both frequency and dose rate distribution curves were modeled using normal statistics and characterised in terms of the mean (μ) and standard deviation (σ). Results: Evaluation of the HDR units indicated a mean ratio of 1.008 (±0.01) while for LDR the mean ratio was 0.997 (±0.02). The LDR frequency distributions demonstrated a variation of σ values extending from 1.4 to 3.0% of μ. It was shown that this non-uniformity in source strength introduced an uncertainty in the treatment planning process of between 0.8 and 1.8% when compared to the assumption of uniform source strength. Conclusions: The results of this intercomparison indicate dosimetric consistency between centres for both LDR and HDR units. The distribution of LDR source strengths were within expected limits and the resultant dose rate distributions were considered clinically acceptable

  18. Pressures Detector Calibration and Measurement

    CERN Document Server

    AUTHOR|(CDS)2156315

    2016-01-01

    This is report of my first and second projects (of 3) in NA61. I did data taking and analysis in order to do calibration of pressure detectors and verified it. I analyzed the data by ROOT software using the C ++ programming language. The first part of my project was determination of calibration factor of pressure sensors. Based on that result, I examined the relation between pressure drop, gas flow rate of in paper filter and its diameter.

  19. Intercomparison of aerosol instruments: number concentration

    International Nuclear Information System (INIS)

    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

  20. Radiative-convective equilibrium model intercomparison project

    Science.gov (United States)

    Wing, Allison A.; Reed, Kevin A.; Satoh, Masaki; Stevens, Bjorn; Bony, Sandrine; Ohno, Tomoki

    2018-03-01

    RCEMIP, an intercomparison of multiple types of models configured in radiative-convective equilibrium (RCE), is proposed. RCE is an idealization of the climate system in which there is a balance between radiative cooling of the atmosphere and heating by convection. The scientific objectives of RCEMIP are three-fold. First, clouds and climate sensitivity will be investigated in the RCE setting. This includes determining how cloud fraction changes with warming and the role of self-aggregation of convection in climate sensitivity. Second, RCEMIP will quantify the dependence of the degree of convective aggregation and tropical circulation regimes on temperature. Finally, by providing a common baseline, RCEMIP will allow the robustness of the RCE state across the spectrum of models to be assessed, which is essential for interpreting the results found regarding clouds, climate sensitivity, and aggregation, and more generally, determining which features of tropical climate a RCE framework is useful for. A novel aspect and major advantage of RCEMIP is the accessibility of the RCE framework to a variety of models, including cloud-resolving models, general circulation models, global cloud-resolving models, single-column models, and large-eddy simulation models.

  1. Aircraft to aircraft intercomparison during SEMAPHORE

    Science.gov (United States)

    Lambert, Dominique; Durand, Pierre

    1998-10-01

    During the Structure des Echanges Mer-Atmosphère, Propriétés des Hétérogénéités Océaniques: Recherche Expérimentale (SEMAPHORE) experiment, performed in the Azores region in 1993, two French research aircraft were simultaneously used for in situ measurements in the atmospheric boundary layer. We present the results obtained from one intercomparison flight between the two aircraft. The mean parameters generally agree well, although the temperature has to be slightly shifted in order to be in agreement for the two aircraft. A detailed comparison of the turbulence parameters revealed no bias. The agreement is good for variances and is satisfactory for fluxes and skewness. A thorough study of the errors involved in flux computation revealed that the greatest accuracy is obtained for latent heat flux. Errors in sensible heat flux are considerably greater, and the worst results are obtained for momentum flux. The latter parameter, however, is more accurate than expected from previous parameterizations.

  2. Intercomparison for individual monitoring. Vol. 1

    International Nuclear Information System (INIS)

    1991-10-01

    Twenty-one laboratories from 19 countries participated in the Intercomparison. The exposures were conducted in May and June of 1988, and the dosimeters were returned to the participating laboratories for processing. The results were returned to the IAEA in late 1988. They were reviewed and compiled at the end of the year. The technical background for the CRP is described in the papers appearing in Parts 1 and 2 of this report. The results are summarized in Parts 3 and 4. An important aspect of the programme was comparison of the techniques used to evaluate the participants' dosimeters (Part 5). There are a number of technical and philosophical issues related to implementation of the ICRU operational quantities, particularly as they relate to needs of Agency Member States (Part 6). Various aspects of the dosimetry system affect the accuracy and precision of the overall results (Part 7). The report concludes with a Summary and Conclusions in Part 8, and a complete list of the participants is shown in Part 9. (orig./DG)

  3. Intercomparison between ICRP60 and ICRP103

    International Nuclear Information System (INIS)

    Mahdy, M. T. A.

    2014-04-01

    In this project inter-comparison between the recommendations from ICRP publication 60, 1900 and the recommendations from ICRP publication 103, 2007 is made. The present 2007 recommendations is an update based on the latest available scientific information of the biology and physics of radiation exposure .This comparison covers the Exposure situations, Tissue Weighting Factors wT, Radiation Weighting Factors wR, and the three Fundamental Principles of Radiological Protection and the protection of the environment. ICRP has retained its fundamental hypothesis for the induction of stochastic effects of linearity of dose and effect without threshold and a dose and dose-rate effectiveness factor (DDREF) of 2 to derive nominal risk coefficients for low doses and low dose rates. While the overall detriment from low radiation doses has remained unchanged, ICRP has made adjustments to the values of the radiation and tissue weighting factors. In particular, the tissue weighting factor for breast has increased while that for gonads has decreased. There are some presentational changes to the system of protection. While ICRP has maintained the three fundamental principles-justification, optimization of protection, and dose limitation-it has attempted to develop a more holistic approach to radiological protection covering all exposure situations-planned, existing and emergency and all radiation sources, whether of natural or artificial origin. Dose constraints and reference levels are categorized into three bands which should assist in rationalizing the many values of dose restrictions given in earlier ICRP publications. (au)

  4. The IAEA intercomparison for individual monitoring

    International Nuclear Information System (INIS)

    Griffith, R.V.; Boehm, J.; Herrman, D.; Strachotinsky, C.; Thompson, I.M.G.

    1990-01-01

    In 1985 the International Commission on Radiation Units and Measurements introduced a new set of operational quantities for radiation protection purposes through Report 39. The International Atomic Energy Agency has been concerned with the impact of possible adoption of these quantities by its 113 Member States. Thus the Agency implemented a Coordinated Research Programme on Intercomparison for Individual Monitoring in 1987. The first phase completed with a Research Coordination meeting of the participants in April, 1989. Photon exposures were provided at 11 energies over a range from 18 keV to 1.25 MeV at three standards laboratories in Austria, the GDR and the UK. Technical coordination was provided by the PTB, Braunschweig. Twenty one laboratories from 19 countries participated with film, TLD of various types, and combination dosemeters. Irradiations were performed on the IAEA 30 cm cubic, water-filled phantom that is in use throughout its network of 61 Secondary Standard Dosimetry Laboratories. Conversion coefficients for the IAEA phantom were calculated by the PTB and confirmed through measurements at ASMW in the GDR. Preliminary results indicated that the type of dosemeter (film or TLD) had little effect on the quality of results. The most important factor appears to be the specific techniques used for data interpretation. (author)

  5. Changes in deviation of absorbed dose to water among users by chamber calibration shift.

    Science.gov (United States)

    Katayose, Tetsurou; Saitoh, Hidetoshi; Igari, Mitsunobu; Chang, Weishan; Hashimoto, Shimpei; Morioka, Mie

    2017-07-01

    The JSMP01 dosimetry protocol had adopted the provisional 60 Co calibration coefficient [Formula: see text], namely, the product of exposure calibration coefficient N C and conversion coefficient k D,X . After that, the absorbed dose to water D w  standard was established, and the JSMP12 protocol adopted the [Formula: see text] calibration. In this study, the influence of the calibration shift on the measurement of D w among users was analyzed. The intercomparison of the D w using an ionization chamber was annually performed by visiting related hospitals. Intercomparison results before and after the calibration shift were analyzed, the deviation of D w among users was re-evaluated, and the cause of deviation was estimated. As a result, the stability of LINAC, calibration of the thermometer and barometer, and collection method of ion recombination were confirmed. The statistical significance of standard deviation of D w was not observed, but that of difference of D w among users was observed between N C and [Formula: see text] calibration. Uncertainty due to chamber-to-chamber variation was reduced by the calibration shift, consequently reducing the uncertainty among users regarding D w . The result also pointed out uncertainty might be reduced by accurate and detailed instructions on the setup of an ionization chamber.

  6. The OptIC Data Assimilation Intercomparison: A Statistical Critique

    Science.gov (United States)

    Enting, I. G.; Clisby, N.

    2008-12-01

    The development of improved terrestrial carbon models has assumed great importance because of concerns about significant climate-to-carbon feedback processes. The complexity of the interactions leads to considerable difficulties in the process of model calibration. The OptIC intercomparison explored some aspects of model calibration, using an idealised terrestrial carbon model. Participants were invited to estimate model parameters in various cases defined by specified time series of the model state, with various forms of added noise. The study identified the crucial importance of the choice of cost function. The present analysis revisits the OptIC study, by considering it as an exercise in statistical estimation. This treats the observations as random variables. Consequently parameter estimates, â, based on observations will also be random variables whose distribution is known as the 'sampling distribution'. Key questions for any specific case are: Are departures from â/a_true =1 indication of bias or sampling error? Under what circumstance are uncertainty estimates (of Var[â]) reliable? We consider cases where the estimate is obtained by minimising a cost function, ΘX. Assuming that we know the true form of ℓ, the log likelihood, there are three different characterisations of uncertainty that should be distinguished: (i) The uncertainty from maximum-likelihood estimates, corresponding (either exactly or asymptotically) to the Cramer-Rao bound. In a realistic calibration situation, we won't be able to determine this because the 'true' form of the likelihood is unknown. (ii) The actual uncertainty associated with using a particular cost function. If the true noise distribution is known, this can be calculated in simple cases and determined from simulations in more complicated cases. (iii) The 'formal uncertainty' based on assuming (usually incorrectly) that ΘX is the true likelihood. In the first stage of the analysis, the distinctions are illustrated by

  7. Whole-body counter intercomparison measurements in Hungary and Italy

    Energy Technology Data Exchange (ETDEWEB)

    Andrasi, A. [Atomic Energy Research Institute, Budapest (Hungary). KFKI; Tarroni, G. [ENEA, Centro Ricerche `Ezio Clementel`, Bologna (Italy). Dipt. Ambiente

    1999-01-01

    In the frame of a co-operation agreement between Austrian Research Center Seibersdorf, Italian ENEA Institute for Radiation Protection and Hungarian KFKI Atomic Energy Research Centre, an intercomparison on WBC measurements using a modular bottle phantom was performed during 1995 in Hungary, on May-July 1996 in the Northern part of Italy. Results related to the relative bias for the three body masses are reported, together with indication of their compliance with ANSI report N13.30. It turned out that majority of the results were found to be within the performance criteria of the ANSI report, however there were also few outfalling results which were a good indication to check and improve the reliability of calibration and/or other methodological procedures. In the contrary of the expectance, the results related to 20 kg phantom resulted not significantly worse than those obtained for the adult phantom indicating the capacity for the participating WBC centres of measuring people from the general population. [Italiano] Nell`ambito di un accordo di collaborazione tra il Centro di Ricerca di Seibersdorf (Austria), l`Istituto per la Radioprotezione dell`ENEA (ENEA AMB PRO IRP) ed il Centro di Ricerca per l`Energia Atomica KFKI di Budapest (Ungheria), si e` svolto un interconfronto su misure WBC basato sull`utilizzo di un unico fantoccio modulare a bottiglie cui hanno partecipato centri WBC Ungheresi (1995) ed Italiani (Maggio-Giugno 1996). Nel presente rapporto tecnico vengono presentati i risultati ottenuti ed una loro analisi impostata sui criteri di valutazione recentemente proposti dall`ANSI nel rapporto N. 13.30. Sulla base di tale criterio la maggior parte dei risultati dell`interconfronto rientra nell`intervallo di accettabilita`; nei pochi casi di non accettabilita` si rende invece necessaria una revisione dei dati di calibrazione e delle metodologie. Contrariamente a quanto si poteva prevedere, i risultati relativi al fantoccio da 20 kg appaiono sostanzialmente

  8. Automatic calibration of gamma spectrometers

    International Nuclear Information System (INIS)

    Tluchor, D.; Jiranek, V.

    1989-01-01

    The principle is described of energy calibration of the spectrometric path based on the measurement of the standard of one radionuclide or a set of them. The entire computer-aided process is divided into three main steps, viz.: the insertion of the calibration standard by the operator; the start of the calibration program; energy calibration by the computer. The program was selected such that the spectrum identification should not depend on adjustment of the digital or analog elements of the gamma spectrometric measuring path. The ECL program is described for automatic energy calibration as is its control, the organization of data file ECL.DAT and the necessary hardware support. The computer-multichannel analyzer communication was provided using an interface pair of Canberra 8673V and Canberra 8573 operating in the RS-422 standard. All subroutines for communication with the multichannel analyzer were written in MACRO 11 while the main program and the other subroutines were written in FORTRAN-77. (E.J.). 1 tab., 4 refs

  9. Field intercomparison of prevailing sonic anemometers

    Science.gov (United States)

    Mauder, Matthias; Zeeman, Matthias J.

    2018-01-01

    Three-dimensional sonic anemometers are the core component of eddy covariance systems, which are widely used for micrometeorological and ecological research. In order to characterize the measurement uncertainty of these instruments we present and analyse the results from a field intercomparison experiment of six commonly used sonic anemometer models from four major manufacturers. These models include Campbell CSAT3, Gill HS-50 and R3, METEK uSonic-3 Omni, R. M. Young 81000 and 81000RE. The experiment was conducted over a meadow at the TERENO/ICOS site DE-Fen in southern Germany over a period of 16 days in June of 2016 as part of the ScaleX campaign. The measurement height was 3 m for all sensors, which were separated by 9 m from each other, each on its own tripod, in order to limit contamination of the turbulence measurements by adjacent structures as much as possible. Moreover, the high-frequency data from all instruments were treated with the same post-processing algorithm. In this study, we compare the results for various turbulence statistics, which include mean horizontal wind speed, standard deviations of vertical wind velocity and sonic temperature, friction velocity, and the buoyancy flux. Quantitative measures of uncertainty, such as bias and comparability, are derived from these results. We find that biases are generally very small for all sensors and all computed variables, except for the sonic temperature measurements of the two Gill sonic anemometers (HS and R3), confirming a known transducer-temperature dependence of the sonic temperature measurement. The best overall agreement between the different instruments was found for the mean wind speed and the buoyancy flux.

  10. Tenth ORNL Personnel Dosimetry Intercomparison Study

    International Nuclear Information System (INIS)

    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 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

  11. AQCS 1990. Intercomparison runs, reference materials

    International Nuclear Information System (INIS)

    1990-01-01

    The purpose of the Analytical Quality Control Services (AQCS) programme provided by the International Atomic Energy Agency (Agency) is to assist laboratories engaged in the analysis of nuclear, environmental, biological, and materials of marine origin for radionuclide, major, minor and trace elements, as well as stable isotopes using atomic and nuclear analytical techniques, to check the quality of their work. Such a control is necessary since results of analytical activities may be the basis upon which economic, administrative, medical or legal decisions are taken; they must, therefore, be documented to be sufficiently reliable. The Agency has instituted the AQCS-programme which for 1990 will involve distributing samples for Intercomparison Runs and Reference Materials in a way similar to that of previous years. The Agency's Analytical Quality Control Services (AQCS) programme provides mainly three types of materials: materials which can be used in analytical laboratories working in the fields of nuclear technology and isotope hydrology. These include uranium ore Reference Materials and other substances of interest for nuclear fuel technology as well as stable isotope Reference Materials for mass spectrometric determination of isotope ratios in natural waters; materials with known content of uranium, thorium and/or transuranium elements or fission products for the determination of environmental radioactivity or control of nuclear safety; materials for use in the determination of stable trace elements in environmental, biomedical and marine research. Radiochemical methods such as neutron activation or isotope dilution analysis are often used in the determination of such trace elements and constitute an important contribution of nuclear techniques to applied science. Tabs

  12. Reference values and evaluation of the results of intercomparisons

    International Nuclear Information System (INIS)

    Aigner, H.; Deron, S.; Kuhn, E.

    1981-01-01

    The need of a reference value for the composition of materials distributed in intercomparisons is generally recognized. A single reference laboratory or a group of reference laboratories may be used to establish this reference value. The respective advantages and limitations of the two approaches are discussed. The reference measurements must be evaluated to provide the confidence limits of the reference value but also an estimate of the possible heterogeneity of the materials and its samples. The results of the intercomparison measurements should themselves be evaluated to test and discuss the significance of the biases of individual and selected groups of laboratories or techniques. The approach taken by the Analytical Quality Control Services of the International Atomic Energy Agency is illustrated by the SR-1 intercomparison on uranium assay in UO 2 powder

  13. Optimal interpolation method for intercomparison of atmospheric measurements.

    Science.gov (United States)

    Ridolfi, Marco; Ceccherini, Simone; Carli, Bruno

    2006-04-01

    Intercomparison of atmospheric measurements is often a difficult task because of the different spatial response functions of the experiments considered. We propose a new method for comparison of two atmospheric profiles characterized by averaging kernels with different vertical resolutions. The method minimizes the smoothing error induced by the differences in the averaging kernels by exploiting an optimal interpolation rule to map one profile into the retrieval grid of the other. Compared with the techniques published so far, this method permits one to retain the vertical resolution of the less-resolved profile involved in the intercomparison.

  14. Analysis of laboratory intercomparison data: a matter of independence

    Directory of Open Access Journals (Sweden)

    Mauro F. Rebelo

    2003-05-01

    Full Text Available When laboratory intercomparison exercises are conducted, there is no a priori dependence of the concentration of a certain compound determined in one laboratory to that determined by another(s. The same applies when comparing different methodologies. A existing data set of total mercury readings in fish muscle samples involved in a Brazilian intercomparison exercise was used to show that correlation analysis is the most effective statistical tool in this kind of experiments. Problems associated with alternative analytical tools such as mean or paired 't'-test comparison and regression analysis are discussed.

  15. International intercomparison of neutron spectra evaluating methods using activation detectors

    International Nuclear Information System (INIS)

    Fischer, A.

    1975-06-01

    The international intercomparison of neutron spectrum evaluation methods using activation detectors was organized by the IAEA in 1971 - 1972. All of the contributions and the results of a critical evaluation are presented here. The spectra of different contributors are compared to a reference spectrum by means of different integrals and weighting functions. Different cross section sets, foil numbers, energy point systems, guess spectra used by the contributors cause differences in the resulting spectra. The possible ways of separating these effects are also investigated. Suggestions are made for the organization of a new intercomparison on the basis of more uniform input data. (orig.) [de

  16. A Synthesis of VIIRS Solar and Lunar Calibrations

    Science.gov (United States)

    Eplee, Robert E.; Turpie, Kevin R.; Meister, Gerhard; Patt, Frederick S.; Fireman, Gwyn F.; Franz, Bryan A.; McClain, Charles R.

    2013-01-01

    The NASA VIIRS Ocean Science Team (VOST) has developed two independent calibrations of the SNPP VIIRS moderate resolution reflective solar bands using solar diffuser and lunar observations through June 2013. Fits to the solar calibration time series show mean residuals per band of 0.078-0.10%. There are apparent residual lunar libration correlations in the lunar calibration time series that are not accounted for by the ROLO photometric model of the Moon. Fits to the lunar time series that account for residual librations show mean residuals per band of 0.071-0.17%. Comparison of the solar and lunar time series shows that the relative differences in the two calibrations are 0.12-0.31%. Relative uncertainties in the VIIRS solar and lunar calibration time series are comparable to those achieved for SeaWiFS, Aqua MODIS, and Terra MODIS. Intercomparison of the VIIRS lunar time series with those from SeaWiFS, Aqua MODIS, and Terra MODIS shows that the scatter in the VIIRS lunar observations is consistent with that observed for the heritage instruments. Based on these analyses, the VOST has derived a calibration lookup table for VIIRS ocean color data based on fits to the solar calibration time series.

  17. Assessment of the results of the 1998 Intercomparison of Individual Monitoring Systems under IAEA Model Project RLA/9/030

    International Nuclear Information System (INIS)

    Da Silva, Teogenes

    1999-01-01

    In this report the results of an intercomparison program within the framework of the IAEA model project RLA/9/030 are presented. This is the first phase of the study the main purpose was to establish a mechanism to identify and improve the current situation of each country as far as the performance of each individual monitoring system is concerned. This phase as was coordinated by Brazil through the Centro de Desenvolvimento da Tecnologia Nuclear that verified the performance of the participant laboratories. The following countries were invited to participate in the 1998 intercomparison: Bolivia, Costa Rica, Guatemala, Nicaragua, Panama, Jamaica and Paraguay. The performance of the laboratories was evaluated for dose assessment in terms of photon dose equivalent Hx

  18. Results of the 1999. Intercomparison of Individual Monitoring Systems under the IAEA Model Project RLA/9/030

    International Nuclear Information System (INIS)

    Da Silva, Teogenes

    2000-01-01

    In this report the results of the second phase of the intercomparison program within the framework of the IAEA model project RLA/9/030 are presented. In this second phase the objective was to evaluate the performance in terms of the quantity personal dose equivalent, Hp (10) for x and gamma radiation in the energy range form 20 KeV to 1.25 MeV. The main purpose of phase II should be the verification of the quality and reliability of the personnel monitoring system of each participating country. The Centro de Desenvolvimento da Tecnologia Nuclear was the reference laboratory that verified the performance of the participant laboratories. The following countries were invited to participate in the 1999 intercomparison: Bolivia, Colombia, Costa Rica, Dominican Republic, el Salvador, Guatemala, Jamaica, Nicaragua, Panama and Paraguay

  19. Evaluation of NAA laboratory results in inter-comparison on determination of trace elements in food and environmental samples

    International Nuclear Information System (INIS)

    Diah Dwiana Lestiani; Syukria Kurniawati; Natalia Adventini

    2012-01-01

    Inter-comparison program is a good tool for improving quality and to enhance the accuracy and precision of the analytical techniques. By participating in this program, laboratories could demonstrate their capability and ensuring the quality of analysis results generated by analytical laboratories. The Neutron Activation Analysis (NAA) laboratory at National Nuclear Energy Agency of Indonesia (BATAN), Nuclear Technology Center for Materials and Radiometry-PTNBR laboratory participated in inter-comparison tests organized by NAA working group. Inter-comparison BATAN 2009 was the third inter-laboratory analysis test within that project. The participating laboratories were asked to analyze for trace elements using neutron activation analysis as the primary technique. Three materials were distributed to the participants representing foodstuff, and environmental material samples. Samples were irradiated in rabbit facility of G.A. Siwabessy reactor with neutron flux ~ 10 13 n.cm -2 .s -1 , and counted with HPGe detector of gamma spectrometry. Several trace elements in these samples were detected. The accuracy and precision evaluation based on International Atomic Energy Agency (IAEA) criteria was applied. In this paper the PTNBR NAA laboratory results is evaluated. (author)

  20. A Trial Intercomparison of Humidity Generators at Extremes of Range Using Relative Humidity Transmitters

    Science.gov (United States)

    Stevens, M.; Benyon, R.; Bell, S. A.; Vicente, T.

    2008-10-01

    In order to effectively implement the Mutual Recognition Arrangement (MRA) of the International Committee for Weights and Measures (CIPM), national metrology institutes (NMIs) are required to support their claims of calibration and measurement capability (CMC) with a quality system compliant with ISO/IEC 17025, and with suitable evidence of participation in key or supplementary comparisons. The CMC review process, both at regional and inter-regional levels, uses criteria that combine the provisions mentioned above, together with additional evidence demonstrating scientific and technical competence of the institutes. For dew-point temperatures, there are key comparisons in progress under the Consultative Committee for Thermometry (CCT) and under the European regional metrology organisation (EUROMET), together with information available on past regional supplementary comparisons. However, for relative humidity there are, to date, no such comparisons available to support CMC entries. This paper presents and discusses the results of a preliminary investigation of the use of relative humidity and temperature transmitters in order to determine their suitability for the intercomparison of standard humidity generators in support of CMC claims for the calibration of relative humidity instruments. The results of a recent bilateral comparison between 2 NMIs at the extremes of the range up to 98%rh at 70 °C, and down to 1%rh at -40 °C are reported. Specific precautions and recommendations on the use of the devices as transfer standards are presented.

  1. Intercomparison of active personal dosemeters in interventional radiology

    International Nuclear Information System (INIS)

    Clairand, I.; Struelens, L.; Bordy, J. M.; Daures, J.; Debroas, J.; Denozieres, M.; Donadille, L.; Gouriou, J.; Itie, C.; Vaz, P.; D'Errico, F.

    2008-01-01

    The use of active personal dosemeters (APD) in interventional radiology was evaluated by Working Group 9 (Radiation protection dosimetry of medical staff) of the CONRAD project, which is a Coordination Action supported by the European Commission within its sixth Framework Programme. Interventional radiology procedures can be very complex and they can lead to relatively high doses to personnel who stand close to the primary radiation field and are mostly exposed to radiation scattered by the patient. For the adequate dosimetry of the scattered photons, APDs must be able to respond to low-energy [10-100 keV] and pulsed radiation with relatively high instantaneous dose rates. An intercomparison of five APD models deemed suitable for application in interventional radiology was organised in March 2007. The intercomparison used pulsed and continuous radiation beams, at CEA-LIST (Saclay (France)) and IRSN (Fontenay-aux-Roses (France)), respectively. A specific configuration, close to the clinical practice, was considered. The reference dose, in terms of Hp(10), was derived from air kerma measurements and from the measured and calculated energy distributions of the scattered radiation field. Additional Monte Carlo calculations were performed to investigate the energy spectra for different experimental conditions of the intercomparison. The results of this intercomparison are presented in this work and indicate which APDs are able to provide a correct response when used in the specific low-energy spectra and dose rates of pulsed X-rays encountered in interventional radiology. (authors)

  2. Intercomparison of low-level tritium in water

    International Nuclear Information System (INIS)

    Sipka, V.; Zupancic, M.; Hadzisehovic, M.; Bacic, S.; Vukovic, Z.

    1989-01-01

    In 1985 the Section of Isotope Hydrology of the IAEA organized the fourth intercomparison for low-level tritium counting in waters. Four water samples with different 3 H concentration were sent to 85 laboratories willing to participate. The results from the different laboratories were presented in the unified questionnaires and coded. The participation in the intercomparisons for every laboratory doing low-level 3 H measurements in the waters is very important and useful. This is a best way to check the entire procedure and methods of the measurements and the reliability of the standards used. Since our laboratories are doing the natural 3 H concentration measurement in the waters for the environmental control and hydrology reasons it was necessary to take part in this intercomparison. Our standard procedure was applied. The 3 H activity in the samples was measured by liquid scintillation counting after an electrolytic enrichment. The results of our measurements of the four water samples, received from the organizers, are presented on the figures and tables presenting summary of the intercomparison. It is clear that our measurement (procedure and standards) have given satisfactory results (author)

  3. Intercomparison Contracted Partner Institutes for Nuclear Emergency 2007; Ringonderzoek waakvlaminstituten kernongevallenbestrijding 2007

    Energy Technology Data Exchange (ETDEWEB)

    Overwater-van Buuren, R.M.W.; Glastra, P.; Tukker, K.

    2009-07-01

    The quality of the so-called Contracted Partner Institutes (CPI's) is amply complying with the objectives. Nonetheless, some desirable improvements remain, especially issues concerning the calibration of the measuring equipment. These issues emerged during an investigation performed by RIVM, in which the quality of the analysis of water and air samples was tested. In the Netherlands there are eight CPI's, evenly spread across the country, who can inform the government about radioactivity in air and water. The CPIs are part of the Dutch National Plan for Nuclear Emergency Planning and Response, which has been drawn up after the nuclear disaster in Chernobyl. RIVM is coordinating the activities of the CPI's. The Contracted Partner Institutes are tested on a two-yearly base by way of intercomparisons. In these intercomparisons, testing is done on both the timely reporting of the results and on the agreement with the reference value within pre-defined boundaries. Most CPI's were able to deliver the air results within two hours, and the water results within 24 hours. The results of the air samples for one institute were outside the pre-defined boundaries. Four samples were prepared for the intercomparison: an aerosol filter, a charcoal filter, a charcoal cartridge and a water sample. All four contained radionuclides characteristic for nuclear accidents. [Dutch] De kwaliteit van de zogeheten Waakvlaminstituten (WVI's) voldoet in 2007 ruimschoots aan de doelstellingen. Wel zijn enkele verbeteringen wenselijk, vooral op het gebied van kalibratie van de meetopstellingen. Dit blijkt uit onderzoek van het RIVM waarin de kwaliteit is getest van de analyse van water- en luchtmonsters. In Nederland bestaan er verspreid over het land acht WVI's die bij een kernongeval de overheid informeren over radioactiviteit in lucht en water. De WVI's zijn een onderdeel van het Nationaal Plan Kernongevallenbestrijding (NPK), dat is opgesteld enkele jaren na

  4. High dose rate brachytherapy source measurement intercomparison.

    Science.gov (United States)

    Poder, Joel; Smith, Ryan L; Shelton, Nikki; Whitaker, May; Butler, Duncan; Haworth, Annette

    2017-06-01

    This work presents a comparison of air kerma rate (AKR) measurements performed by multiple radiotherapy centres for a single HDR 192 Ir source. Two separate groups (consisting of 15 centres) performed AKR measurements at one of two host centres in Australia. Each group travelled to one of the host centres and measured the AKR of a single 192 Ir source using their own equipment and local protocols. Results were compared to the 192 Ir source calibration certificate provided by the manufacturer by means of a ratio of measured to certified AKR. The comparisons showed remarkably consistent results with the maximum deviation in measurement from the decay-corrected source certificate value being 1.1%. The maximum percentage difference between any two measurements was less than 2%. The comparisons demonstrated the consistency of well-chambers used for 192 Ir AKR measurements in Australia, despite the lack of a local calibration service, and served as a valuable focal point for the exchange of ideas and dosimetry methods.

  5. RCA/IAEA third external dosimetry intercomparison in East Asia

    International Nuclear Information System (INIS)

    Momose, T.; Yamamoto, H.; Cruz Suarez, R.

    2005-01-01

    Full text: Several intercomparison exercises were organized by the International Atomic Energy Agency (IAEA) on the determination of operational quantities at the regional or interregional basis. These exercises revealed significant differences in the approach, methods and assumptions, and consequently in the measurement results obtained by participating laboratories. In the East Asia region, the third phase of the Hp(10) intercomparison, organized within the frame of the Regional Cooperation Agreement (RCA) as a follow-up to previous exercises during 1990-92 and 1995-96, was completed mid-2004. The first phase grouped 25 laboratories from 16 member states, and 4 Secondary Standards Dosimetry Laboratories irradiated dosimeters in 6 different qualities for photon and beta radiations. In the second phase, 23 laboratories from 16 member states participated, and 3 Secondary Standards Dosimetry Laboratories provided irradiation in 5 different radiation qualities simulating workplace fields. The results of the second phase for the determination of operational quantities Hp(d) were satisfactory for all participating Member States, with marked improvement from the first phase; the laboratories demonstrated good performance in both quantities tested. These results underline the importance of such an intercomparison programme as a key element towards the harmonization of quantities and units on an international level. This paper presents the results of this RCA/IAEA intercomparison, and also the forthcoming RCA activities supporting intercomparison runs for the assessment of occupational exposure. Member states strongly recommend that the IAEA continue acting as a focal point for, inter alia, training in all forms, particularly in measurements and dosimetry techniques. This exercise also stressed the importance for the IAEA to take an active role in establishing a network of monitoring laboratories for radiation protection purposes, as it would provide for better information

  6. Delivery of calibration workshops covering herbicide application equipment : final report.

    Science.gov (United States)

    2014-03-31

    Proper herbicide sprayer set-up and calibration are critical to the success of the Oklahoma Department of Transportation (ODOT) herbicide program. Sprayer system set-up and calibration training is provided in annual continuing education herbicide wor...

  7. Quality control tests in dose calibrators used in research laboratories of IPEN

    International Nuclear Information System (INIS)

    Kuahara, Lilian T.; Junior, Amaury C.R.; Martins, Elaine W.; Dias, Carla R.; Correa, Eduardo de L.; Potiens, Maria da Penha A.

    2013-01-01

    The aim of this study was to do the intercomparison between two dose calibrators used in research laboratories at IPEN-CNEN / SP, one being the Capinted NPL-CRC, of the Laboratorio de Calibracao de Instrumentos (LCI) do IPEN, and the other Capintec CRC-15R of the Centro de Radiofarmacia (CR). The standard sources used for carrying out the comparing tests between the two laboratories were 57 Co, 133 Ba and the 13 7 C s

  8. Data Quality Assessment of In Situ and Altimeter Observations Through Two-Way Intercomparison Methods

    Science.gov (United States)

    Guinehut, Stephanie; Valladeau, Guillaume; Legeais, Jean-Francois; Rio, Marie-Helene; Ablain, Michael; Larnicol, Gilles

    2013-09-01

    This proceeding presents an overview of the two-way inter-comparison activities performed at CLS for both space and in situ observation agencies and why this activity is a required step to obtain accurate and homogenous data sets that can then be used together for climate studies or in assimilation/validation tools. We first describe the work performed in the frame of the SALP program to assess the stability of altimeter missions through SSH comparisons with tide gauges (GLOSS/CLIVAR network). Then, we show how the SSH comparison between the Argo array and altimeter time series allows the detection of drifts or jumps in altimeter (SALP program) but also for some Argo floats (Ifremer/Coriolis center). Lastly, we describe how the combine use of altimeter and wind observations helps the detection of drogue loss of surface drifting buoys (GDP network) and allow the computation of a correction term for wind slippage.

  9. NICMOS Cycles 13 and 14 Calibration Plans

    Science.gov (United States)

    Arribas, Santiago; Bergeron, Eddie; de Jong, Roeof; Malhotra, Sangeeta; Mobasher, Bahram; Noll, Keith; Schultz, Al; Wiklind, Tommy; Xu, Chun

    2005-11-01

    This document summarizes the NICMOS Calibration Plans for Cycles 13 and 14. These plans complement the SMOV3b, the Cycle 10 (interim), and the Cycles 11 and 12 (regular) calibration programs executed after the installation of the NICMOS Cooling System (NCS).. These previous programs have shown that the instrument is very stable, which has motivated a further reduction in the frequency of the monitoring programs for Cycle 13. In addition, for Cycle 14 some of these programs were slightly modified to account for 2 Gyro HST operations. The special calibrations on Cycle 13 were focussed on a follow up of the spectroscopic recalibration initiated in Cycle 12. This program led to the discovery of a possible count rate non-linearity, which has triggered a special program for Cycle 13 and a number of subsequent tests and calibrations during Cycle 14. At the time of writing this is a very active area of research. We also briefly comment on other calibrations defined to address other specific issues like: the autoreset test, the SPAR sequences tests, and the low-frequency flat residual for NIC1. The calibration programs for the 2-Gyro campaigns are not included here, since they have been described somewhere else. Further details and updates on specific programs can be found via the NICMOS web site.

  10. NIST display colorimeter calibration facility

    Science.gov (United States)

    Brown, Steven W.; Ohno, Yoshihiro

    2003-07-01

    A facility has been developed at the National Institute of Standards and Technology (NIST) to provide calibration services for color-measuring instruments to address the need for improving and certifying the measurement uncertainties of this type of instrument. While NIST has active programs in photometry, flat panel display metrology, and color and appearance measurements, these are the first services offered by NIST tailored to color-measuring instruments for displays. An overview of the facility, the calibration approach, and associated uncertainties are presented. Details of a new tunable colorimetric source and the development of new transfer standard instruments are discussed.

  11. Mechanics of log calibration

    International Nuclear Information System (INIS)

    Waller, W.C.; Cram, M.E.; Hall, J.E.

    1975-01-01

    For any measurement to have meaning, it must be related to generally accepted standard units by a valid and specified system of comparison. To calibrate well-logging tools, sensing systems are designed which produce consistent and repeatable indications over the range for which the tool was intended. The basics of calibration theory, procedures, and calibration record presentations are reviewed. Calibrations for induction, electrical, radioactivity, and sonic logging tools will be discussed. The authors' intent is to provide an understanding of the sources of errors, of the way errors are minimized in the calibration process, and of the significance of changes in recorded calibration data

  12. Intercomparison of open-path trace gas measurements with two dual-frequency-comb spectrometers

    Directory of Open Access Journals (Sweden)

    E. M. Waxman

    2017-09-01

    Full Text Available We present the first quantitative intercomparison between two open-path dual-comb spectroscopy (DCS instruments which were operated across adjacent 2 km open-air paths over a 2-week period. We used DCS to measure the atmospheric absorption spectrum in the near infrared from 6023 to 6376 cm−1 (1568 to 1660 nm, corresponding to a 355 cm−1 bandwidth, at 0.0067 cm−1 sample spacing. The measured absorption spectra agree with each other to within 5 × 10−4 in absorbance without any external calibration of either instrument. The absorption spectra are fit to retrieve path-integrated concentrations for carbon dioxide (CO2, methane (CH4, water (H2O, and deuterated water (HDO. The retrieved dry mole fractions agree to 0.14 % (0.57 ppm for CO2, 0.35 % (7 ppb for CH4, and 0.40 % (36 ppm for H2O at  ∼  30 s integration time over the 2-week measurement campaign, which included 24 °C outdoor temperature variations and periods of strong atmospheric turbulence. This agreement is at least an order of magnitude better than conventional active-source open-path instrument intercomparisons and is particularly relevant to future regional flux measurements as it allows accurate comparisons of open-path DCS data across locations and time. We additionally compare the open-path DCS retrievals to a World Meteorological Organization (WMO-calibrated cavity ring-down point sensor located along the path with good agreement. Short-term and long-term differences between the open-path DCS and point sensor are attributed, respectively, to spatial sampling discrepancies and to inaccuracies in the current spectral database used to fit the DCS data. Finally, the 2-week measurement campaign yields diurnal cycles of CO2 and CH4 that are consistent with the presence of local sources of CO2 and absence of local sources of CH4.

  13. Asian/Australian region intercalibration and intercomparison programme for radon: statistical analysis and propagation of uncertainity protocols for scintillation cells of the reference laboratory

    International Nuclear Information System (INIS)

    Gan, T.H.; Solomon, S.B.; Peggie, J.R.

    1990-01-01

    A series of intercomparison for radon was orgarnized by the Australian Radiation Laboratory (ARL) for twenty-eight laboratories from nine countries in the Asian/Australasian region. Methodology, results of intercalibration and statistical analysis for the four groups of NEW scintillation cells are described. The variability in the calibration factor of 3.4% for one standard deviation for the NEW set of cells, compared with 5.7% for the OECD cells indicates that the NEW cells measurements give greater consistency to the results. 5 refs., 2 tabs, 1 fig

  14. Proposal of a postal system for Ir-192 sources calibration used in high dose rate brachytherapy with LiF:Mn:Ti thermoluminescent dosemeters

    International Nuclear Information System (INIS)

    Vieira, W.S.; Borges, J.C.; Almeida, C.E.V.

    1998-01-01

    A proposal in order to improve the brachytherapy quality control and to allow postal intercomparison of Ir-192 sources used in high dose rate brachytherapy has been presented. The LiF: Mn: Ti (TLD 100) detector has been selected for such purpose. The experimental array and the TLDs irradiation and calibration techniques, at the treatment units, have been specified in the light of more recent methodology of Ir-192 calibration sources. (Author)

  15. Dose calibrators quality controls in Switzerland: six years of experience

    International Nuclear Information System (INIS)

    Bochud, F.; Spring, Ph.; Baechler, S.; Twerenbold, D.; Linder, R.; Leibundgut, F.

    2006-01-01

    In Switzerland, the legal use of open radioactive sources in nuclear medicine and the general requirements for quality controls are defined in a federal ordinance. The metrological traceability is guaranteed through a directive of the Swiss metrological office (M.E.T.A.S.) that requires each instrument to be monitored at least once a year through either a verification or an intercomparison. The verification is performed onsite by an accredited laboratory with a set of three gamma sources (Co-57, Cs-137 and Co-60) and - if applicable - a beta source (Sr-90/Y- 90). The intercomparison is made through conventional mail. A source of I-131 or Tc- 99 m is measured both in the nuclear medicine department and in an accredited laboratory. The maximum tolerated error is 10% for gamma sources and 20% for beta sources. This methodology guarantees that the instruments have a correct response for most of the energy range used in practice. Not all nuclides are systematically probed and manufacturers are ultimately responsible for the calibration factors. The precision of the measurements performed in Switzerland is satisfactory with only about 6% of the measurements out of the tolerances. This monitoring also allowed us to improve the skills of the personnel and update the park of instruments by getting rid of dose calibrators displaying old units. (authors)

  16. Dose calibrators quality controls in Switzerland: six years of experience

    Energy Technology Data Exchange (ETDEWEB)

    Bochud, F.; Spring, Ph.; Baechler, S. [Institut Universitaire de Radiophysique Appliquee, Lausanne (Switzerland); Twerenbold, D. [METAS, Lindenweg 50, Bern-Wabern (Switzerland); Linder, R. [Bundesamt fur Gesundheit, Abteilung Strahlenschutz, Bern (Switzerland); Leibundgut, F. [Raditec radiation and technology, Schoftland (Switzerland)

    2006-07-01

    In Switzerland, the legal use of open radioactive sources in nuclear medicine and the general requirements for quality controls are defined in a federal ordinance. The metrological traceability is guaranteed through a directive of the Swiss metrological office (M.E.T.A.S.) that requires each instrument to be monitored at least once a year through either a verification or an intercomparison. The verification is performed onsite by an accredited laboratory with a set of three gamma sources (Co-57, Cs-137 and Co-60) and - if applicable - a beta source (Sr-90/Y- 90). The intercomparison is made through conventional mail. A source of I-131 or Tc- 99 m is measured both in the nuclear medicine department and in an accredited laboratory. The maximum tolerated error is 10% for gamma sources and 20% for beta sources. This methodology guarantees that the instruments have a correct response for most of the energy range used in practice. Not all nuclides are systematically probed and manufacturers are ultimately responsible for the calibration factors. The precision of the measurements performed in Switzerland is satisfactory with only about 6% of the measurements out of the tolerances. This monitoring also allowed us to improve the skills of the personnel and update the park of instruments by getting rid of dose calibrators displaying old units. (authors)

  17. Calibration of the SNO+ experiment

    Science.gov (United States)

    Maneira, J.; Falk, E.; Leming, E.; Peeters, S.; SNO+ Collaboration.

    2017-09-01

    The main goal of the SNO+ experiment is to perform a low-background and high-isotope-mass search for neutrinoless double-beta decay, employing 780 tonnes of liquid scintillator loaded with tellurium, in its initial phase at 0.5% by mass for a total mass of 1330 kg of 130Te. The SNO+ physics program includes also measurements of geo- and reactor neutrinos, supernova and solar neutrinos. Calibrations are an essential component of the SNO+ data-taking and analysis plan. The achievement of the physics goals requires both an extensive and regular calibration. This serves several goals: the measurement of several detector parameters, the validation of the simulation model and the constraint of systematic uncertainties on the reconstruction and particle identification algorithms. SNO+ faces stringent radiopurity requirements which, in turn, largely determine the materials selection, sealing and overall design of both the sources and deployment systems. In fact, to avoid frequent access to the inner volume of the detector, several permanent optical calibration systems have been developed and installed outside that volume. At the same time, the calibration source internal deployment system was re-designed as a fully sealed system, with more stringent material selection, but following the same working principle as the system used in SNO. This poster described the overall SNO+ calibration strategy, discussed the several new and innovative sources, both optical and radioactive, and covered the developments on source deployment systems.

  18. An intercomparison of Canadian external dosimetry processors for radiation protection

    International Nuclear Information System (INIS)

    1989-10-01

    The five Canadian external dosimetry processors have participated in a two-stage intercomparison. The first stage involved dosimeters to known radiation fields under controlled laboratory conditions. The second stage involved exposing dosimeters to radiation fields in power reactor working environments. The results for each stage indicated the dose reported by each processor relative to an independently determined dose and relative to the others. The results of the intercomparisons confirm the original supposition: namely that the average differences in reported dose among five processors are much less than the uncertainty limits recommended by the ICRP. This report provides a description of the experimental methods as well as a discussion of the results for each stage. The report also includes a set of recommendations

  19. Results of the 2001 NRPB intercomparison of passive radon detectors

    CERN Document Server

    Howarth, C B

    2002-01-01

    As in previous years, an intercomparison of passive radon detectors was held at NRPB in 2001. Forty-seven laboratories submitted 62 sets of passive detectors to this intercomparison. The exercise included three exposures to radon and its decay products at different equilibrium factors. An additional exposure at the CERN - EU high Energy Reference Facility (CERF) to a simulated cosmic ray spectrum was also offered to participants. After exposure, the detectors were returned to their originating laboratories for assessment. Participants reported the estimated exposure for each detector before they were notified of the exposures given to the detectors. The results obtained by participating laboratories were classified according to the spread of results from detectors exposed together and by the difference between the mean result of each group and the actual exposure given. Thirty-five percent of the laboratories achieved the highest classification for accuracy, while 9% were in the lowest category. The proportio...

  20. Intercomparison of radon gas detectors 1997 at PSI

    International Nuclear Information System (INIS)

    Schuler, Christoph; Butterweck-Dempewolf, Gernot

    1998-05-01

    Between Nov 14 and Nov 20, 1997, the Reference Laboratory for Radon Gas Activity Concentration Measurements at Paul Scherrer Institut performed the 1997 Radon Intercomparison Exercise. Radon gas detectors and instruments were exposed in the PSI Radon Chamber during seven days in a reference atmosphere with an average radon gas concentration of 3860 Bqm -3 . The majority of the participants at this intercomparison were Swiss Radon Gas Measurement Laboratories acknowledged by the Swiss Federal Office for Health. Criteria for this acknowledgement are a deviation of the measurement results to the reference value below 15% (traceability criterion) and a standard deviation of the mean of five detector measurement results below 15% (reproducibility criterion). With the exception of three participants, the results of electret ionisation chambers, track etch detectors and measuring instruments fulfilled the demanded traceability and reproducibility criteria. (author)

  1. Preparation and application of radioactive soil samples for intercomparison

    International Nuclear Information System (INIS)

    Gao Zequan; Li Zhou; Li Pengxiang; Wang Ruijun; Ren Xiaona

    2014-01-01

    This article summarized the preparation process and intercomparison results of the simulated environmental radioactive soil samples. The components of the matrix were: SiO 2 , Al 2 O 3 , Fe 2 O 3 , MgO, CaO, NaCl, KCl and TiO 2 . All of the components were milled, oven-dried, sieved and then blended together. The homogeneity test was according to GB 15000. 5-1994, and no significant differences were observed. The 3 H analysis soils were spiked natural soils with the moisture content of 15%. Eight laboratories attended this intercomparison. The results proves that the preparation of the simulated soils were suitable for the inter-laboratories comparison. (authors)

  2. Intercomparisons in the radiation monitoring network of the Czech Republic

    Energy Technology Data Exchange (ETDEWEB)

    Tuckova, S; Malatova, I [National Radiation Protection Inst., Prague (Czech Republic); Drabova, D [State Office for Nuclear Safety, Prague (Czech Republic)

    1996-12-31

    In Czech Republic, altogether 11 laboratories, equipped by semiconductor gamma spectrometry supply regularly to the Centre of Radiation Monitoring Network the measured data about the radionuclide activity concentration in different environmental samples, participating thus in monitoring of radiation situation in the country. The Center of Radiation Monitoring Network of Czech Republic periodically organizes through its reference laboratories interlaboratory comparison tests ensuring thus quality of the measurements within the radiation monitoring network. A ring intercomparison test was organized in 1994. The piece of steel rather highly contaminated by {sup 60}Co was used. In the intercomparison test 1994-1995 of pulverized concrete breeze-block containing fly ash with natural radionuclides were used. Results of this measurement is given as an example (authors).

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

  4. Tropospheric ozone lidar intercomparison experiment, TROLIX '91, field phase report

    International Nuclear Information System (INIS)

    Boesenberg, J.; Ancellet, G.; Bergwerff, H.; Cossart, G. v.; Fiedler, J.; Jonge, C. de; Mellqvist, J.; Mitev, V.; Sonnemann, G.; Swart, D.; Wallinder, E.

    1993-01-01

    The Tropospheric Ozone Lidar Intercomparison Experiment TROLIX '91 has been initiated as part of the TESLAS subproject of the cooperative programme EUROTRAC. It has been performed in June 1991 at the Rijksinstitut voor Volksgezondheid en Milieuhygiene (RIVM) in Bilthoven, The Netherlands. The experiment was based on the simultaneous operation of different types of differential absorption lidars (DIAL), a special version of a Differential Optical Absorption Spectroscopy Instrument (DOAS), helicopter borne in situ instruments, and many other supporting measurements. After a short introduction to the general methodology the instruments are described, the experimental operations are explained, and a selection of data are presented. Some examples are given for the results of the intercomparison, as far as they have been available at the present stage of evaluation. The main purpose of this report, however, is to provide an overview over the material collected during the experiment, on order to facilitate further detailed studies in cooperation between the different groups which have participated. (orig.)

  5. Synthesis Polarimetry Calibration

    Science.gov (United States)

    Moellenbrock, George

    2017-10-01

    Synthesis instrumental polarization calibration fundamentals for both linear (ALMA) and circular (EVLA) feed bases are reviewed, with special attention to the calibration heuristics supported in CASA. Practical problems affecting modern instruments are also discussed.

  6. Intercomparison of TCCON and MUSICA Water Vapour Products

    Science.gov (United States)

    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.

  7. A Methodological Inter-Comparison of Gridded Meteorological Products

    Science.gov (United States)

    Newman, A. J.; Clark, M. P.; Longman, R. J.; Giambelluca, T. W.; Arnold, J.

    2017-12-01

    Here we present a gridded meteorology inter-comparison using the state of Hawaíi as a testbed. This inter-comparison is motivated by two general goals: 1) the broad user community of gridded observation based meteorological fields should be aware of inter-product differences and the reasons they exist, which allows users to make informed choices on product selection to best meet their specific application(s); 2) we want to demonstrate the utility of inter-comparisons to meet the first goal, yet highlight that they are limited to mostly generic statements regarding attribution of differences that limits our understanding of these complex algorithms and obscures future research directions. Hawaíi is a useful testbed because it is a meteorologically complex region with well-known spatial features that are tied to specific physical processes (e.g. the trade wind inversion). From a practical standpoint, there are now several monthly climatological and daily precipitation and temperature datasets available that are being used for impact modeling. General conclusions that have emerged are: 1) differences in input station data significantly influence product differences; 2) prediction of precipitation occurrence is crucial across multiple metrics; 3) derived temperature statistics (e.g. diurnal temperature range) may have large spatial differences across products; and 4) attribution of differences to methodological choices is difficult and may limit the outcomes of these inter-comparisons, particularly from a development viewpoint. Thus, we want to continue to move the community towards frameworks that allow for multiple options throughout the product generation chain and allow for more systematic testing.

  8. Development of a transfer instrument for neutron dosimetry intercomparison

    International Nuclear Information System (INIS)

    Greene, D.; Miles, J.

    1974-01-01

    Comparisons are reported for fast neutron dosemeters which were designed to be transportable so as to enable intercomparisons between institutions using neutrons for radiotherapy or radiobiology. The systems considered are : 1) the ferrous sulphate dosemeter, 2) the lithium fluoride thermoluminescent dosemeter, 3) ionization chambers with various walls and gases. Work on photographic film dosimetry indicated that the system was not suitable and was not pursued. The sources used were 60 Co, the cyclotron at Hammersmith Hospital in London and 252 Cf

  9. GODAE Inter-Comparisons in the Tasman and Coral Seas

    Science.gov (United States)

    2012-08-01

    and salinity. All have their strengths and weaknesses, and each system out-performs all others in one aspect or another. With few exceptions, all... Auckland and Fiji (Fig 1), was occupied during the inter- comparison period. The observed T section from this line is shown in Fig 6a. Comparisons of T...has certain strengths and weaknesses. Inter-comparisons are regarded as valuable exer- cises that provide important insights into the ocean forecast

  10. Intercomparison of personal dose equivalent measurements by active personal dosimeters. Final report of a joint IAEA-EURADOS project

    International Nuclear Information System (INIS)

    2007-11-01

    Active personal dosimeters (APD) are widely used in many countries, i.e. in the medical field and as operational dosimeters in nuclear power plants. Their use as legal dosimeters is already established in a few countries, and will increase in the near future. In the majority of countries, APDs have not undergone accreditation programmes or intercomparisons. In 2001, an EURADOS (European Radiation Dosimetry Group) Working Group on harmonization of individual monitoring was formed, funded by the European Commission, in the fifth framework programme, and by the participating institutes. The work addressed four issues; inter alia also an inventory of new developments in individual monitoring with an emphasis on the possibilities and performance of active (electronic) dosimeters for both photon/beta and neutron dosimetry. Within the work on this issue, a catalogue of the most extensively used active personal dosimeters (APDs) suitable for individual monitoring was made. On the basis of the knowledge gained in this activity, the organization of an international intercomparison, which would address APDs, was considered of great value to the dosimetric community. The IAEA in cooperation with EURADOS organized such an intercomparison in which most of the testing criteria as described in two internationally accepted standards (IEC61526 and IEC61283) were used. Additionally, simulated workplace fields were used for testing the APD reactions to pulsed X ray fields and mixed gamma/X ray fields. This is the first time that results of comparisons of such types are published, which is of great importance for APD end users in medical diagnostic and surgery X ray applications. Nine suppliers from six countries in Europe and the USA participated in the intercomparison with 13 different models. One of the models was a special design for extremity dose measurements. Irradiations and readout was done by two accredited calibration laboratories in Belgium and France and the French

  11. ORNL calibrations facility

    International Nuclear Information System (INIS)

    Berger, C.D.; Gupton, E.D.; Lane, B.H.; Miller, J.H.; Nichols, S.W.

    1982-08-01

    The ORNL Calibrations Facility is operated by the Instrumentation Group of the Industrial Safety and Applied Health Physics Division. Its primary purpose is to maintain radiation calibration standards for calibration of ORNL health physics instruments and personnel dosimeters. This report includes a discussion of the radioactive sources and ancillary equipment in use and a step-by-step procedure for calibration of those survey instruments and personnel dosimeters in routine use at ORNL

  12. A soil sampling intercomparison exercise for the ALMERA network

    International Nuclear Information System (INIS)

    Belli, Maria; Zorzi, Paolo de; Sansone, Umberto; Shakhashiro, Abduhlghani; Gondin da Fonseca, Adelaide; Trinkl, Alexander; Benesch, Thomas

    2009-01-01

    Soil sampling and analysis for radionuclides after an accidental or routine release is a key factor for the dose calculation to members of the public, and for the establishment of possible countermeasures. The IAEA organized for selected laboratories of the ALMERA (Analytical Laboratories for the Measurement of Environmental Radioactivity) network a Soil Sampling Intercomparison Exercise (IAEA/SIE/01) with the objective of comparing soil sampling procedures used by different laboratories. The ALMERA network is a world-wide network of analytical laboratories located in IAEA member states capable of providing reliable and timely analysis of environmental samples in the event of an accidental or intentional release of radioactivity. Ten ALMERA laboratories were selected to participate in the sampling exercise. The soil sampling intercomparison exercise took place in November 2005 in an agricultural area qualified as a 'reference site', aimed at assessing the uncertainties associated with soil sampling in agricultural, semi-natural, urban and contaminated environments and suitable for performing sampling intercomparison. In this paper, the laboratories sampling performance were evaluated.

  13. Second Latin American intercomparison on internal dose assessment

    International Nuclear Information System (INIS)

    Rojo, A.; Puerta, N.; Gossio, S.; Gomez Parada, I.; Cruz Suarez, R.; Lopez, E.; Medina, C.; Lastra Boylan, J.; Pinheiro Ramos, M.; Mora Ramirez, E.; Alves dos Reis, A.; Yanez, H.; Rubio, J.; Vironneau Janicek, L.; Somarriba Vanegas, F.; Puerta Ortiz, J.; Salas Ramirez, M.; Lopez Bejerano, G.; Da Silva, T.; Miri Oliveira, C.; Teran, M.; Alfaro, M.; Garcia, T.; Angeles, A.; Dure Romero, E.; Farias de Lima, F.

    2016-01-01

    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. Nineteen 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. (authors)

  14. SECOND LATIN AMERICAN INTERCOMPARISON ON INTERNAL DOSE ASSESSMENT.

    Science.gov (United States)

    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. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  15. A soil sampling intercomparison exercise for the ALMERA network

    Energy Technology Data Exchange (ETDEWEB)

    Belli, Maria [Istituto Superiore per la Protezione e la Ricerca Ambientale (ISPRA), Via di Castel Romano 100, I-00128 Roma (Italy)], E-mail: maria.belli@apat.it; Zorzi, Paolo de [Istituto Superiore per la Protezione e la Ricerca Ambientale (ISPRA), Via di Castel Romano 100, I-00128 Roma (Italy)], E-mail: paolo.dezorzi@isprambiente.it; Sansone, Umberto [International Atomic Energy Agency (IAEA), Agency' s Laboratories Seibersdorf, A-2444 Seibersdorf (Austria)], E-mail: u.sansone@iaea.org; Shakhashiro, Abduhlghani [International Atomic Energy Agency (IAEA), Agency' s Laboratories Seibersdorf, A-2444 Seibersdorf (Austria)], E-mail: a.shakhashiro@iaea.org; Gondin da Fonseca, Adelaide [International Atomic Energy Agency (IAEA), Agency' s Laboratories Seibersdorf, A-2444 Seibersdorf (Austria)], E-mail: a.gondin-da-fonseca-azeredo@iaea.org; Trinkl, Alexander [International Atomic Energy Agency (IAEA), Agency' s Laboratories Seibersdorf, A-2444 Seibersdorf (Austria)], E-mail: a.trinkl@iaea.org; Benesch, Thomas [International Atomic Energy Agency (IAEA), Agency' s Laboratories Seibersdorf, A-2444 Seibersdorf (Austria)], E-mail: t.benesch@iaea.org

    2009-11-15

    Soil sampling and analysis for radionuclides after an accidental or routine release is a key factor for the dose calculation to members of the public, and for the establishment of possible countermeasures. The IAEA organized for selected laboratories of the ALMERA (Analytical Laboratories for the Measurement of Environmental Radioactivity) network a Soil Sampling Intercomparison Exercise (IAEA/SIE/01) with the objective of comparing soil sampling procedures used by different laboratories. The ALMERA network is a world-wide network of analytical laboratories located in IAEA member states capable of providing reliable and timely analysis of environmental samples in the event of an accidental or intentional release of radioactivity. Ten ALMERA laboratories were selected to participate in the sampling exercise. The soil sampling intercomparison exercise took place in November 2005 in an agricultural area qualified as a 'reference site', aimed at assessing the uncertainties associated with soil sampling in agricultural, semi-natural, urban and contaminated environments and suitable for performing sampling intercomparison. In this paper, the laboratories sampling performance were evaluated.

  16. Reactor neutron activation analysis on reference materials from intercomparison runs

    International Nuclear Information System (INIS)

    Pantelica, A.; Salagean, M.

    2003-01-01

    A review of using the Instrumental Neutron Activation Analysis (INAA) technique in our laboratory to determine major, minor and trace elements in mineral and biological samples from international intercomparison runs organised by IAEA Vienna, IAEA-MEL Monaco, 'pb-anal' Kosice, INCT Warszawa and IPNT Krakow is presented. Neutron irradiation was carried out at WWR-S reactor in Bucharest (short and long irradiation) during 1982-1997 and at TRIGA reactor in Pitesti (long irradiation) during the later period. The following type of materials were analysed: soils, marine sediments, uranium phosphate ore, water sludge, copper flue dust, whey powder, yeast, cereal flour (rye and wheat), marine animal tissue (mussel, garfish and tuna fish), as well as vegetal tissue (seaweed, cabbage, spinach, alfalfa, algae, tea leaves and herbs). The following elements could be, in general, determined: Ag, As, Au, Ba, Br, Ca, Ce, Co, Cr, Cs, Eu, Fe, Hf, Hg, K, La, Lu, Mo, Na, Nd, Ni, Rb, Sb, Sc, Se, Sm, Sr, Ta, Tb, Th, U, W, Yb and Zn of long-lived radionuclides, as well as Al, Ca, Cl, Cu, Mg, Mn, and Ti of short-lived radionuclides. Data obtained in our laboratory for various matrix samples presented and compared with the intercomparison certified values. The intercomparison exercises offer to the participating laboratories the opportunity to test the accuracy of their analytical methods as well as to acquire valuable Reference Materials/ standards for future analytical applications. (authors)

  17. Intercomparison of Methods for Determination of Resonant Frequency Shift of a Microstrip Patch Antenna Loaded with Hevea Rubber Latex

    Directory of Open Access Journals (Sweden)

    Nor Zakiah Yahaya

    2014-01-01

    Full Text Available This paper presents an intercomparison between the finite element method, method of moment, and the variational method to determine the effect of moisture content on the resonant frequency shift of a microstrip patch loaded with wet material. The samples selected for this study were Hevea rubber latex with different percentages of moisture content from 35% to 85%. The results were compared with the measurement data in the frequency range between 1 GHz and 4 GHz. It was found that the finite element method is the most accurate among all the three computational techniques with 0.1 mean error when compared to the measured resonant frequency shift. A calibration equation was obtained to predict moisture content from the measured frequency shift with an accuracy of 2%.

  18. DRDC Ottawa Participation in the SILENE Accident Dosimetry Intercomparison Exercise. June 10-21, 2002

    National Research Council Canada - National Science Library

    Prud'homme-Lalonde, L

    2002-01-01

    .... The SILENE International Accident Dosimetry Intercomparison Exercise at Valduc, France in June 2002 coincided with DRDC Ottawa work designed to refine its proposed criticality dosimetry system...

  19. Method of calibration for portable detectors of ionizing radiation

    International Nuclear Information System (INIS)

    Leal, Carlos; Carrizales, Lila; Guacaran, Douglas; Moreno, Ailed; Duran, Jose

    2008-01-01

    Full text: The LSCD is beginning a process of accreditation by the national authority of Venezuela (CENCAMER), so we felt the need to modify existing protocols calibration, suggested by the IAEA (Technical Reports Series No 133) to be adjusted in accordance with international standards of ISO 17025 EA-4/02 and Mexican standard NOM-021-NUCL-2002, adapting the calibration procedure of portable radiation detectors to those standards. The procedure used in the LSCD, conducts an intercomparison between measures between the standard reference and to calibrate the instrument, thus verifying the correct operation of the equipment and its usefulness to the individual or environmental radiation monitoring, not to exceed the limits primary for the public and occupationally Staff Exposed (POE), and propose a simple way to perform this calibration procedure and comply with the standard international and national standards, ensuring the proper functioning of the instruments calibrated. One of the calculations that has proven to be a useful tool in the verification of the conditions of operating the same, it is uncertainty, this procedure allows to characterize the response of individual detector, depending on the constraints specified by the manufacturer, to optimize the calibration is necessary to consider the multiple factors that can affect the measure and evaluate the response of the same, so it is vitally important estimating the typical uncertainty associated with the calibration technique employed, but this calculation is not trivial, depends on the type of detector found usually between 5% to 20%, both in uncertainty as the linearity, which are the parameters that are set to consider an instrument in good or bad condition. Typical are calibrated are: monitors air Geiger-Muller, Ionization cameras, detector of Neutron's, Proportional Counter, Personal dosimeters. (author)

  20. FTIR Calibration Methods and Issues

    Science.gov (United States)

    Perron, Gaetan

    Over the past 10 years, several space-borne FTIR missions were launched for atmospheric research, environmental monitoring and meteorology. One can think of the Michelson Interferometer for Passive Atmospheric Sounding (MIPAS) launched by the European Space Agency, the Atmospheric Chemistry Experiment (ACE) launched by the Canadian Space Agency, the Tropospheric Emission Spectrometer (TES) launched by NASA and the Infrared Atmospheric Sounding Interferometer (IASI) launched by Eumetsat in Europe. Others are near to be launched, namely the Cross-track Infrared Sounder (CrIS) from the Integrated Program Of- fice in the United States and the Thermal And Near infrared Sensor for carbon Observation (TANSO) from the Japan Aerospace Exploration Agency. Moreover, several missions under definition foresee the use of this technology as sensor, e.g. Meteosat Third Generation (MTG), Eumetsat Polar System (EPS) and the Premier mission, one of the six candidates of the next ESA Earth Explorer Core Mission. In order to produce good quality products, calibration is essential. Calibrated data is the output of three main sub-systems that are tightly coupled: the instrument, the calibration targets and the level 1B processor. Calibration requirements must be carefully defined and propagated to each sub-system. Often, they are carried out by different parties which add to the complexity. Under budget and schedule pressure, some aspects are sometimes neglected and jeopardized final quality. For space-borne FTIR, level 1B outputs are spectra that are radiometrically, spectrally calibrated and geolocated. Radiometric calibration means to assign an intensity value in units to the y-axis. Spectral calibration means to assign to the x-axis the proper frequency value in units. Finally, geolocated means to assign a target position over the earth geoid i.e. longitude, latitude and altitude. This paper will present calibration methods and issues related to space-borne FTIR missions, e.g. two

  1. 40 CFR 160.63 - Maintenance and calibration of equipment.

    Science.gov (United States)

    2010-07-01

    ...) PESTICIDE PROGRAMS GOOD LABORATORY PRACTICE STANDARDS Equipment § 160.63 Maintenance and calibration of..., maintenance, testing, calibration, and/ or standardization of equipment, and shall specify, when appropriate... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Maintenance and calibration of...

  2. Dosimetry audits and intercomparisons in radiotherapy: A Malaysian profile

    International Nuclear Information System (INIS)

    Noor, Noramaliza M.; Nisbet, A.; Hussein, M.; Chu S, Sarene; Kadni, T.; Abdullah, N.; Bradley, D.A.

    2017-01-01

    Quality audits and intercomparisons are important in ensuring control of processes in any system of endeavour. Present interest is in control of dosimetry in teletherapy, there being a need to assess the extent to which there is consistent radiation dose delivery to the patient. In this study we review significant factors that impact upon radiotherapy dosimetry, focusing upon the example situation of radiotherapy delivery in Malaysia, examining existing literature in support of such efforts. A number of recommendations are made to provide for increased quality assurance and control. In addition to this study, the first level of intercomparison audit i.e. measuring beam output under reference conditions at eight selected Malaysian radiotherapy centres is checked; use being made of 9 µm core diameter Ge-doped silica fibres (Ge-9 µm). The results of Malaysian Secondary Standard Dosimetry Laboratory (SSDL) participation in the IAEA/WHO TLD postal dose audit services during the period between 2011 and 2015 will also been discussed. In conclusion, following review of the development of dosimetry audits and the conduct of one such exercise in Malaysia, it is apparent that regular periodic radiotherapy audits and intercomparison programmes should be strongly supported and implemented worldwide. The programmes to-date demonstrate these to be a good indicator of errors and of consistency between centres. A total of ei+ght beams have been checked in eight Malaysian radiotherapy centres. One out of the eight beams checked produced an unacceptable deviation; this was found to be due to unfamiliarity with the irradiation procedures. Prior to a repeat measurement, the mean ratio of measured to quoted dose was found to be 0.99 with standard deviation of 3%. Subsequent to the repeat measurement, the mean distribution was 1.00, and the standard deviation was 1.3%. - Highlights: • We review significant factors that impact upon radiotherapy dosimetry, • We carried out the

  3. SPRT Calibration Uncertainties and Internal Quality Control at a Commercial SPRT Calibration Facility

    Science.gov (United States)

    Wiandt, T. J.

    2008-06-01

    The Hart Scientific Division of the Fluke Corporation operates two accredited standard platinum resistance thermometer (SPRT) calibration facilities, one at the Hart Scientific factory in Utah, USA, and the other at a service facility in Norwich, UK. The US facility is accredited through National Voluntary Laboratory Accreditation Program (NVLAP), and the UK facility is accredited through UKAS. Both provide SPRT calibrations using similar equipment and procedures, and at similar levels of uncertainty. These uncertainties are among the lowest available commercially. To achieve and maintain low uncertainties, it is required that the calibration procedures be thorough and optimized. However, to minimize customer downtime, it is also important that the instruments be calibrated in a timely manner and returned to the customer. Consequently, subjecting the instrument to repeated calibrations or extensive repeated measurements is not a viable approach. Additionally, these laboratories provide SPRT calibration services involving a wide variety of SPRT designs. These designs behave differently, yet predictably, when subjected to calibration measurements. To this end, an evaluation strategy involving both statistical process control and internal consistency measures is utilized to provide confidence in both the instrument calibration and the calibration process. This article describes the calibration facilities, procedure, uncertainty analysis, and internal quality assurance measures employed in the calibration of SPRTs. Data will be reviewed and generalities will be presented. Finally, challenges and considerations for future improvements will be discussed.

  4. Laboratory implantation for well type ionization chambers calibration

    International Nuclear Information System (INIS)

    Vianello, E.A.; Dias, D.J.; Almeida, C.E. de

    1998-01-01

    The Radiological Science Laboratory is implanting a service for calibration of well type chambers by IAEA training program. The kerma rate in the air (mu Gy/h) of the linear Cs-137 reference source CDCS-J4 have been determined using a well type chamber Standard Imaging HDR-1000 model, which have been calibrated at Secondary Standard Laboratory Calibration of IAEA, whereas two HDR-1000 Plus chambers were calibrated too, following the same standards. The results were compared with Wisconsin University calibration certification and has demonstrated that well type ionization chamber calibration can be used in brachytherapy for several kinds of radionuclides. (Author)

  5. Results of the analysis of the intercomparison samples of the depleted uranium dioxide SR-20

    International Nuclear Information System (INIS)

    Aigner, H.; Deron, S.; Kuhn, E.; Ronesch, K.; Zoigner, A.

    Samples of a homogeneous powder of depleted uranium dioxide, SR-20, were distributed to 32 laboratories in January 1980 for intercomparison of the precisions and accuracies of wet chemical assay. 11 laboratories reported their results (ANNEX 1). 5 laboratories applied titration procedures, 4 of them applied methods derived from the Davies and Gray procedure (1), 2 laboratories used controlled potential coulometry, 2 laboratories used precipitation procedures, 1 laboratory used fluorimetry and 1 laboratory used activation analysis. An analysis of variance yields for each laboratory the estimates of the measurement errors, the dissolution or treatment errors and the random calibration errors. The measurement errors vary between 0.01% and 1.7% relative. The differences to the reference value vary between -9.1% and +0.92% uranium, but 9 laboratories agree within +-1%U with the reference value. The mean bias of these 9 laboratories is equal to +0.04%U. The standard deviation of the biases of these 9 laboratories is equal to 0.36%.U

  6. Field intercomparison of three current meters in an environment free from high frequency motion

    Science.gov (United States)

    Larouche, Pierre; Deguise, Jean-Claude

    1989-06-01

    An intercomparison of three different types of current meter was performed in an Arctic environment where wave action was absent, permitting the evaluation of the instruments under natural conditions of weak currents and cold water. The instruments were an Aanderaa RCMS4S, an Inter Ocean S4 and an EG&G-Neil Brown Smart Acoustic Current Meter (SACM). The S4 and the SACM both showed their ability to measure very small currents as opposed to the RCM4S which is limited by a mechanical rotor threshold. The agreement of the direction was better between the RCM4S and the SACM than between the RCM4S and the S4. Due to the misalignment of the Aanderaa vane in very weak currents, direction differences between the instruments of either pair can, however, reach 180°. The misalignment also shields the Aanderaa rotor leading to underestimation of current speed. The threshold for a good speed reading for the Aanderaa can be put conservatively at 5 cm s -1. Above this value, the RCM4S over-responded compared to both the S4 and the SACM. The source of that problem seems to be related to different calibrations of the instruments. Finally a power spectrum analysis showed that the RCM4S, when not influenced by wave action, can produce a measure of the energy as good as that of a vector averaging instrument.

  7. Results of the analysis of the intercomparison samples of the depleted uranium dioxide SR-10

    International Nuclear Information System (INIS)

    Aigner, H.; Deron, S.; Kuhn, E.; Zoigner, A.

    1981-01-01

    Samples of a homogeneous powder of depleted uranium dioxide, SR-10, were distributed to 27 laboratories in February 1979 for intercomparison of the precisions and accuracies of wet chemical assay. 7 laboratories reported their results. 6 laboratories applied titration procedures, 4 of them applied methods derived from the Davies and Gray procedure (1), and one laboratory used controlled potential coulometry. An analysis of variance yields for each laboratory the estimates of the measurement errors, the dissolution or treatment errors and the random calibration errors. The measurement errors vary between 0.01% and 0.10% relative. The differences to the reference value vary between -0.48% and +0.87% uranium, but 5 laboratories agree within +-0.25% U with the reference value. The biases of 5 laboratories are greater than expected from their random errors. The mean bias of the 7 laboratories is equal to +0.03% U. The standard deviation of the laboratory biases is equal to 0.43% U. (author)

  8. GOSAT and OCO-2 Inter-comparison on Measured Spectral Radiance and Retrieved Carbon Dioxide

    Science.gov (United States)

    Kataoka, F.; Kuze, A.; Shiomi, K.; Suto, H.; Crisp, D.; Bruegge, C. J.; Schwandner, F. M.

    2016-12-01

    TANSO-FTS onboard GOSAT and grating spectrometer on OCO-2 use different measurement techniques to measure carbon dioxide (CO2) and molecular oxygen (O2). Both instruments observe sunlight reflected from the Earth's surface in almost the same spectral range. As a first step in cross calibrating these two instruments, we compared spectral radiance observations within the three short wave infrared (SWIR) spectral bands centered on the O2 A-band (O2A), the weak CO2 band near 1.6 microns (Weak-CO2) and 2.06 micons (Strong-CO2) bands at temporally coincident and spatially collocated points. In this work, we reconciled the different size of the footprints and evaluated at various types of surface targets such as ocean, desert and forest. For radiometric inter-comparisons, we consider long term instrument sensitivity degradation in orbit and differences in viewing geometry and associated differences in surface bidirectional reflectance distribution function (BRDF). Measured spectral radiances agree very well within 5% for all bands. This presentation will summarize these comparisons of GOSAT and OCO-2 spectral radiance observations and associated estimates of carbon dioxide and related parameters retrieved with the same algorithm at matchup points. We will also discuss instrument related uncertainties from various target observations.

  9. Laboratory Experiments and Instrument Intercomparison Studies of Carbonaceous Aerosol Particles

    Energy Technology Data Exchange (ETDEWEB)

    Davidovits, Paul [Boston College, Chestnut Hill, MA (United States)

    2015-10-20

    Aerosols containing black carbon (and some specific types of organic particulate matter) directly absorb incoming light, heating the atmosphere. In addition, all aerosol particles backscatter solar light, leading to a net-cooling effect. Indirect effects involve hydrophilic aerosols, which serve as cloud condensation nuclei (CCN) that affect cloud cover and cloud stability, impacting both atmospheric radiation balance and precipitation patterns. At night, all clouds produce local warming, but overall clouds exert a net-cooling effect on the Earth. The effect of aerosol radiative forcing on climate may be as large as that of the greenhouse gases, but predominantly opposite in sign and much more uncertain. The uncertainties in the representation of aerosol interactions in climate models makes it problematic to use model projections to guide energy policy. The objective of our program is to reduce the uncertainties in the aerosol radiative forcing in the two areas highlighted in the ASR Science and Program Plan. That is, (1) addressing the direct effect by correlating particle chemistry and morphology with particle optical properties (i.e. absorption, scattering, extinction), and (2) addressing the indirect effect by correlating particle hygroscopicity and CCN activity with particle size, chemistry, and morphology. In this connection we are systematically studying particle formation, oxidation, and the effects of particle coating. The work is specifically focused on carbonaceous particles where the uncertainties in the climate relevant properties are the highest. The ongoing work consists of laboratory experiments and related instrument inter-comparison studies both coordinated with field and modeling studies, with the aim of providing reliable data to represent aerosol processes in climate models. The work is performed in the aerosol laboratory at Boston College. At the center of our laboratory setup are two main sources for the production of aerosol particles: (a

  10. An intercomparison of Monte Carlo codes used for in-situ gamma-ray spectrometry

    International Nuclear Information System (INIS)

    Hurtado, S.; Villa, M.

    2010-01-01

    In-situ gamma-ray spectrometry is widely used for monitoring of natural as well as man-made radionuclides and corresponding gamma fields in the environment or working places. It finds effective application in the operational and accidental monitoring of nuclear facilities and their vicinity, waste depositories, radioactive contamination measurements and environmental mapping or geological prospecting. In order to determine accurate radionuclide concentrations in these research fields, Monte Carlo codes have recently been used to obtain the efficiency calibration of in-situ gamma-ray detectors. This work presents an inter-comparison between two Monte Carlo codes applied to in-situ gamma-ray spectrometry. On the commercial market, Canberra has its LABSOCS/ISOCS software which is relatively inexpensive. The ISOCS mathematical efficiency calibration software uses a combination of Monte Carlo calculations and discrete ordinate attenuation computations. Efficiencies can be generated in a few minutes in the field and can be modified easily if needed. However, it has been reported in the literature that ISOCS computation method is accurate on average only within 5%, and additionally in order to use LABSOCS/ISOCS it is necessary a previous characterization of the detector by Canberra, which is an expensive process. On the other hand, the multipurpose and open source GEANT4 takes significant computer time and presents a non-friendly but powerful toolkit, independent of the manufacturer of the detector. Different experimental measurements of calibrated sources were performed with a Canberra portable HPGe detector and compared to the results obtained using both Monte Carlo codes. Furthermore, a variety of efficiency calibrations for different radioactive source distributions were calculated and tested, like plane shapes or containers filled with different materials such as soil, water, etc. LabSOCS simulated efficiencies for medium and high energies were given within an

  11. Participation of the ARN (Autoridad Regulatoria Nuclear) in the quality assessment program of the EML-USDOE

    International Nuclear Information System (INIS)

    Bonino, N.O.; Equillor, H.E.; Fernandez, J.A.; Gavini, R.M.; Grinman, A.D.R.; Serdeiro, N.H.; Lewis, E.C.; Bomben, A.M.; Diodati, J.M.

    1998-01-01

    Full text: A radiochemical laboratory must count with optimized analytical techniques and calibrated measurement systems in order to get reliable results. In addition to the internal controls that each laboratory must carry out, it is indispensable to include in the quality assurance programs, intercomparisons with qualified laboratories. The Nuclear Regulatory Authority (ARN) of the Republica Argentina participates since 1995, in the Quality Assessment Program organized by the Environmental Measurements Laboratory - EML, of the United States. The participation in this program consist in: 1) Measurement of different gamma emitters in 4 environmental matrixes: water, filter, soil and vegetation; 2) Determination of actinides in the named matrixes; 3) Determination of tritium and iron-55 in water; 4) Determination of strontium-90 in water, filter, soil and vegetation; 5) Gross alpha and gross beta measurement in water and filter. In this paper, the results of the ARN in the six previous intercomparisons are exposed. An analysis of the deviations of the informed dates related to the EML values are made, and they are compared with the results of the rest of the participating laboratories. The determination methods and the measurement systems utilized in each matrix and for each radionuclide, are mentioned. (author) [es

  12. An international intercomparison of passive dosemeters, electronic dosemeters and dose rate meters used for environmental radiation measurements

    DEFF Research Database (Denmark)

    Bøtter-Jensen, L.; Thompson, I.M.G.

    1995-01-01

    during 1994. The intercomparison was organised by the Physikalisch Technische Bundesanstalt (PTB), Braunschweig, Germany, and by the Riso National Laboratory, Roskilde, Denmark. This paper describes the intercomparison experiments performed at the newly established Riso Natural Environmental Radiation...

  13. The ATLAS Electromagnetic Calorimeter Calibration Workshop

    CERN Multimedia

    Hong Ma; Isabelle Wingerter

    The ATLAS Electromagnetic Calorimeter Calibration Workshop took place at LAPP-Annecy from the 1st to the 3rd of October; 45 people attended the workshop. A detailed program was setup before the workshop. The agenda was organised around very focused presentations where questions were raised to allow arguments to be exchanged and answers to be proposed. The main topics were: Electronics calibration Handling of problematic channels Cluster level corrections for electrons and photons Absolute energy scale Streams for calibration samples Calibration constants processing Learning from commissioning Forty-five people attended the workshop. The workshop was on the whole lively and fruitful. Based on years of experience with test beam analysis and Monte Carlo simulation, and the recent operation of the detector in the commissioning, the methods to calibrate the electromagnetic calorimeter are well known. Some of the procedures are being exercised in the commisssioning, which have demonstrated the c...

  14. Intersatellite Calibration of Microwave Radiometers for GPM

    Science.gov (United States)

    Wilheit, T. T.

    2010-12-01

    The aim of the GPM mission is to measure precipitation globally with high temporal resolution by using a constellation of satellites logically united by the GPM Core Satellite which will be in a non-sunsynchronous, medium inclination orbit. The usefulness of the combined product depends on the consistency of precipitation retrievals from the various microwave radiometers. The calibration requirements for this consistency are quite daunting requiring a multi-layered approach. The radiometers can vary considerably in their frequencies, view angles, polarizations and spatial resolutions depending on their primary application and other constraints. The planned parametric algorithms will correct for the varying viewing parameters, but they are still vulnerable to calibration errors, both relative and absolute. The GPM Intersatellite Calibration Working Group (aka X-CAL) will adjust the calibration of all the radiometers to a common consensus standard for the GPM Level 1C product to be used in precipitation retrievals. Finally, each Precipitation Algorithm Working Group must have its own strategy for removing the residual errors. If the final adjustments are small, the credibility of the precipitation retrievals will be enhanced. Before intercomparing, the radiometers must be self consistent on a scan-wise and orbit-wise basis. Pre-screening for this consistency constitutes the first step in the intercomparison. The radiometers are then compared pair-wise with the microwave radiometer (GMI) on the GPM Core Satellite. Two distinct approaches are used for sake of cross-checking the results. On the one hand, nearly simultaneous observations are collected at the cross-over points of the orbits and the observations of one are converted to virtual observations of the other using a radiative transfer model to permit comparisons. The complementary approach collects histograms of brightness temperature from each instrument. In each case a model is needed to translate the

  15. Environmental monitoring radiological programs for the nuclear centre and the low level radioactive waste facility in Mexico

    International Nuclear Information System (INIS)

    Quintero, E.; Cervantes, L.; Rojas, V.

    2006-01-01

    The National Institute of Nuclear Research of Mexico (ININ) has its Laboratory of Environmental Radiological Monitoring, (LVRA), to assure the critical population and the environment they are not exposed to radiation doses greater than the limits established by the national and international legislation, this laboratory carries out environmental monitoring radiological programs the Nuclear Centre and its surroundings and the Low Level Radioactive Waste Facility (CADER) and its around. In order to carry out these programs the LVRA has rooms for evaporation, drying, grinding, ashing of environmental and food samples, and a laboratory for gamma ray spectrometry, liquid scintillation, alpha-beta gross counting and computer room. Since the year 2000 the (ININ) has tried to implant the quality system ISO 9001:2000 including a its (LVRA). This quality system includes: a Plan of Quality, Quality Manual, programs of technical and administrative document elaboration, technical and administrative procedures, technical and administrative qualification programmes for the laboratory staff, maintenance and calibration programs for measurement systems and finally participation in national and international exercises of intercomparison. The ININ counts with the management of quality assurance to verify these programs, in addition, our Nuclear Regulatory Commission (CNSNS) carries out periodic audits to authorize the of use and handling of radioactive and nuclear material licenses of these facilities. In this work we presented the advances and difficulties found in the implantation of the quality system, also we present the benefits obtained with uses of this system, the samples analyses results, and the calculation of the annual dose to the critical population for the last five years. In addition, we presented the calculation the radionuclides concentration tendencies in different sample types, according to our (CNSNS) requirements. In the same way the results of the calibrations

  16. Calibration of Flick standards

    International Nuclear Information System (INIS)

    Thalmann, Ruedi; Spiller, Jürg; Küng, Alain; Jusko, Otto

    2012-01-01

    Flick standards or magnification standards are widely used for an efficient and functional calibration of the sensitivity of form measuring instruments. The results of a recent measurement comparison have shown to be partially unsatisfactory and revealed problems related to the calibration of these standards. In this paper the influence factors for the calibration of Flick standards using roundness measurement instruments are discussed in detail, in particular the bandwidth of the measurement chain, residual form errors of the device under test, profile distortions due to the diameter of the probing element and questions related to the definition of the measurand. The different contributions are estimated using simulations and are experimentally verified. Also alternative methods to calibrate Flick standards are investigated. Finally the practical limitations of Flick standard calibration are shown and the usability of Flick standards both to calibrate the sensitivity of roundness instruments and to check the filter function of such instruments is analysed. (paper)

  17. Report on the intercomparison for the isotope standards limestone KH 2 and polyethylene foil PEF 1

    International Nuclear Information System (INIS)

    Gerstenberger, H.; Herrmann, M.

    1983-01-01

    The isotope abundance of 13 C and 18 O of a carbonate was measured by an intercomparison in order to create a new working standard for the mass spectrometric determination of isotopic variations in natural materials. For the same purpose a polyethylene was subjected an intercomparison and the abundance of 13 C and D has been determined. (author)

  18. Initial Results of an Intercomparison of AMS-Based Atmospheric 14CO2 Measurements

    NARCIS (Netherlands)

    Miller, John; Lehman, Scott; Wolak, Chad; Turnbull, Jocelyn; Dunn, Gregory; Graven, Heather; Keeling, Ralph; Meijer, Harro A. J.; Aerts-Bijma, Anita Th; Palstra, Sanne W. L.; Smith, Andrew M.; Allison, Colin; Southon, John; Xu, Xiaomei; Nakazawa, Takakiyo; Aoki, Shuji; Nakamura, Toshio; Guilderson, Thomas; LaFranchi, Brian; Mukai, Hitoshi; Terao, Yukio; Uchida, Masao; Kondo, Miyuki

    2013-01-01

    This article presents results from the first 3 rounds of an international intercomparison of measurements of Delta(CO2)-C-14 in liter-scale samples of whole air by groups using accelerator mass spectrometry (AMS). The ultimate goal of the intercomparison is to allow the merging of Delta(CO2)-C-14

  19. Community Intercomparison Suite (CIS) v1.4.0: A tool for intercomparing models and observations

    NARCIS (Netherlands)

    Watson-Parris, Duncan; Schutgens, Nick; Cook, Nicholas; Kipling, Zak; Kershaw, Philip; Gryspeerdt, Edward; Lawrence, Bryan; Stier, Philip

    2016-01-01

    The Community Intercomparison Suite (CIS) is an easy-to-use command-line tool which has been developed to allow the straightforward intercomparison of remote sensing, in-situ and model data. While there are a number of tools available for working with climate model data, the large diversity of

  20. Intercomparison study of atmospheric methane and carbon dioxide concentrations measured at the Ebre River Delta Station

    Science.gov (United States)

    Occhipinti, Paola; Morguí, Josep Anton; Àgueda, Alba; Batet, Oscar; Borràs, Sílvia; Cañas, Lídia; Curcoll, Roger; Grossi, Claudia; Nofuentes, Manel; Vazquez, Eusebi; Rodó, Xavier

    2015-04-01

    In the framework of the ClimaDat project, IC3 has established a network of eight monitoring stations across the Iberian Peninsula and the Canarian Archipelago with the aim of studying climate processes. The monitoring station at the Ebre River Delta (DEC3) is located in the Ebre River Delta Natural Park (40° 44' N; 0° 47' E) and it is characterized by the typical North-Western Mediterranean climate. Since 2013, atmospheric greenhouse gases (GHG) and 222Rn tracer gas together with the meteorological parameters are continuously measured from a 10 m a.g.l. height tower. Atmospheric GHG (CO2, CH4, CO and N2O) concentrations are determined using a Picarro analyzer G2301 (CO2 and CH4) and a modified gas chromatograph (GC) Agilent 6890N (CO2, CH4, CO and N2O). Open data access is available from the www.climadat.es website. Data collected at the DEC3 station are also submitted to the InGOS platform since this station is part of the InGOS European infrastructure project. Researchers from the Laboratory of the Atmosphere and the Oceans (LAO) at IC3 have performed an intercomparison study at the DEC3 site between three different Picarro analyzers (two Picarro G2301 and one Picarro G2301M), a Los Gatos Research (LGR) analyzer and the GC system already installed at the station. The aim of this study is to compare and assess the measuring agreement between the four optical gas analyzers and the GC. In the first part of the experiment, all instruments have been calibrated using NOAA gases as primary standards analyzing five Praxair provided targets to evaluate the precision of the measuring instruments. Max Plank Institute (MPI) gases have been used as secondary standards for the GC whereas Praxair provided tanks are used as secondary standards for the Picarro and the LGR analyzers. In the second part of the experiment, atmospheric GHG were measured from natural atmospheric air taken from a 10 m a.g.l. inlet. Daily cycles of GHG measurements were carried out using different

  1. Dosimetry audits and intercomparisons in radiotherapy: A Malaysian profile

    Science.gov (United States)

    M. Noor, Noramaliza; Nisbet, A.; Hussein, M.; Chu S, Sarene; Kadni, T.; Abdullah, N.; Bradley, D. A.

    2017-11-01

    Quality audits and intercomparisons are important in ensuring control of processes in any system of endeavour. Present interest is in control of dosimetry in teletherapy, there being a need to assess the extent to which there is consistent radiation dose delivery to the patient. In this study we review significant factors that impact upon radiotherapy dosimetry, focusing upon the example situation of radiotherapy delivery in Malaysia, examining existing literature in support of such efforts. A number of recommendations are made to provide for increased quality assurance and control. In addition to this study, the first level of intercomparison audit i.e. measuring beam output under reference conditions at eight selected Malaysian radiotherapy centres is checked; use being made of 9 μm core diameter Ge-doped silica fibres (Ge-9 μm). The results of Malaysian Secondary Standard Dosimetry Laboratory (SSDL) participation in the IAEA/WHO TLD postal dose audit services during the period between 2011 and 2015 will also been discussed. In conclusion, following review of the development of dosimetry audits and the conduct of one such exercise in Malaysia, it is apparent that regular periodic radiotherapy audits and intercomparison programmes should be strongly supported and implemented worldwide. The programmes to-date demonstrate these to be a good indicator of errors and of consistency between centres. A total of ei+ght beams have been checked in eight Malaysian radiotherapy centres. One out of the eight beams checked produced an unacceptable deviation; this was found to be due to unfamiliarity with the irradiation procedures. Prior to a repeat measurement, the mean ratio of measured to quoted dose was found to be 0.99 with standard deviation of 3%. Subsequent to the repeat measurement, the mean distribution was 1.00, and the standard deviation was 1.3%.

  2. An intercomparison exercise on radionuclides in sediment samples

    Energy Technology Data Exchange (ETDEWEB)

    Nielsen, S.P.

    1996-07-01

    An intercomparison exercise on artificial and natural radionuclides in two sediment samples, one from the Baltic Sea and one from the Kattegat, has been carried out under the EKO-1 project or the Nordic Safety Research Programme (NKS) for the period 1996-97. The measurement techniques have included direct gamma-ray spectrometry with Ge and NaI detectors, and radiochemical procedures followed by beta counting and alpha spectrometry. The participants have 21 laboratories. Results were submitted for Cs-137, Cs-134, Co-60, Sb-125, Pu-239,240, Pu-238, Am-241, Sr-90, Ra-226, Th-232 and K-40, Pb-210, Po-210 and U-235. The analytical performance of the participants was evaluated for those radionuclides where six or more data sets were received. Statistical tests were made to see if individual results agreed with overall average radionuclide concentrations in the two sediment materials within target standard deviations. The results of these tests show that for Cs-137, Cs-134, Ra-226, Th-232 and K-40 the analytical performance criteria were not met for 20-40% of the data sets. For plutonium isotopes the tests show that the performance criteria were not met for 13% of the data sets. Tests of overall analytical performance show that 61% of the data sets do not meet the combined performance criteria. This shows that there is room for considerable improvement of analytical quality for most of the laboratories that have participated in this intercomparison. The intercomparison exercise has furthermore demonstrated several elementary problems in analytical work. (au) 57 tabs., 16 ills., 1 ref.

  3. An intercomparison exercise on radionuclides in sediment samples

    International Nuclear Information System (INIS)

    Nielsen, S.P.

    1996-07-01

    An intercomparison exercise on artificial and natural radionuclides in two sediment samples, one from the Baltic Sea and one from the Kattegat, has been carried out under the EKO-1 project or the Nordic Safety Research Programme (NKS) for the period 1996-97. The measurement techniques have included direct gamma-ray spectrometry with Ge and NaI detectors, and radiochemical procedures followed by beta counting and alpha spectrometry. The participants have 21 laboratories. Results were submitted for Cs-137, Cs-134, Co-60, Sb-125, Pu-239,240, Pu-238, Am-241, Sr-90, Ra-226, Th-232 and K-40, Pb-210, Po-210 and U-235. The analytical performance of the participants was evaluated for those radionuclides where six or more data sets were received. Statistical tests were made to see if individual results agreed with overall average radionuclide concentrations in the two sediment materials within target standard deviations. The results of these tests show that for Cs-137, Cs-134, Ra-226, Th-232 and K-40 the analytical performance criteria were not met for 20-40% of the data sets. For plutonium isotopes the tests show that the performance criteria were not met for 13% of the data sets. Tests of overall analytical performance show that 61% of the data sets do not meet the combined performance criteria. This shows that there is room for considerable improvement of analytical quality for most of the laboratories that have participated in this intercomparison. The intercomparison exercise has furthermore demonstrated several elementary problems in analytical work. (au) 57 tabs., 16 ills., 1 ref

  4. Report on the intercomparison run: radionuclides in seawater and plankton collected outside Mururoa Atoll

    International Nuclear Information System (INIS)

    Ballestra, S.; Noshkin, V.

    1991-07-01

    This report contains a brief outline of the sampling program and a summary of all available radiological data provided by the three participants. The Direction des Centres d'Experimentations Nucleaires Laboratory (DIRCEN-CEA), Montlhery, France; The Lawrence Livermore National Laboratory (LLNL), Livermore, CA, USA; and the IAEA International Laboratory of Marine Radioactivity, (IAEA-ILMR), Principality of Monaco. The IAEA-ILMR results are complied in a separate report by Ballestra et al. (1991) that has details of the program and copies of the protocol and the ''Proces-verbal de constat'' produced by the legal representative at the end of the sampling program. A sampling program was designed to collect 3 large volume seawater and 2 plankton samples from locations near the territorial limit outside Mururoa Atoll. The different samples were to be used for a radiological intercomparison exercise. A legal representative from Papeete, Tahiti (French Polynesia) was given the task to verify the authenticity of the samples and to ensure that the protocol was followed by the participants. 4 refs, 1 fig., 3 tabs

  5. RF impedance measurement calibration

    International Nuclear Information System (INIS)

    Matthews, P.J.; Song, J.J.

    1993-01-01

    The intent of this note is not to explain all of the available calibration methods in detail. Instead, we will focus on the calibration methods of interest for RF impedance coupling measurements and attempt to explain: (1). The standards and measurements necessary for the various calibration techniques. (2). The advantages and disadvantages of each technique. (3). The mathematical manipulations that need to be applied to the measured standards and devices. (4). An outline of the steps needed for writing a calibration routine that operated from a remote computer. For further details of the various techniques presented in this note, the reader should consult the references

  6. IAEA/IDEAS intercomparison exercise on internal dose assessment

    International Nuclear Information System (INIS)

    Doerfel, H.; Andrasi, A.; Cruz-Suarez, R.; Castellani, C. M.; Hurtgen, C.; Marsh, J.; Zeger, J.

    2007-01-01

    An Internet based intercomparison exercise on assessment of occupational exposure due to intakes of radionuclides has been performed to check the applicability of the 'General Guidelines for the Assessment of Internal Dose from Monitoring Data' developed by the IDEAS group. There were six intake cases presented on the Internet and 81 participants worldwide reported solutions to these cases. Results of the exercise indicate that the guidelines have a positive influence on the methodologies applied for dose assessments and, if correctly applied, improve the harmonisation of assessed doses. (authors)

  7. The Geoengineering Model Intercomparison Project (GeoMIP)

    KAUST Repository

    Kravitz, Ben

    2011-01-31

    To evaluate the effects of stratospheric geoengineering with sulphate aerosols, we propose standard forcing scenarios to be applied to multiple climate models to compare their results and determine the robustness of their responses. Thus far, different modeling groups have used different forcing scenarios for both global warming and geoengineering, complicating the comparison of results. We recommend four experiments to explore the extent to which geoengineering might offset climate change projected in some of the Climate Model Intercomparison Project 5 experiments. These experiments focus on stratospheric aerosols, but future experiments under this framework may focus on different means of geoengineering. © 2011 Royal Meteorological Society.

  8. Methods and advantages of intercomparisons of TLDs for environmental monitoring

    International Nuclear Information System (INIS)

    Ranogajec-Komor, M.; Klemic, G.

    1997-01-01

    One of the most difficult tasks facing the international community is the monitoring of environmental radiation for potential increases due to facility accidents or weapons activity. Monitoring networks have been established to provide a record of natural background radiation as well as measure any radiation releases from a facility. Thermoluminescent dosimeters (TLDs) are an important element of such networks and are the most widely used passive detector for environmental monitoring. In order to reach a high international standard in the application of TLDs in routine environmental monitoring, there is a need for a intercomparisons. (authors)

  9. Intercomparison of radiation protection instruments based on microdosimetric principles

    International Nuclear Information System (INIS)

    Dietze, G.; Guldbakke, S.; Kluge, H.; Schmitz, T.

    1986-11-01

    Dosemeters based on low-pressure tissue-equivalent proportional counters were developed for the application in radiation protection area monitoring by several groups in Europe. Five different prototypes have been intercompared in a 60 Co photon field, in monoenergetic neutron fields with various energies between 73 keV and 5 MeV and in three neutron fields at a 252 Cf source moderated by a D 2 O sphere. This report describes the radiation fields, the measuring devices and first results of the intercomparison. Additional measurements with a system used in microdosimetry and with a conventional dose equivalent rate meter for neutrons (Rem Counter) were also described. (orig.) [de

  10. International nuclear accident dosimetry intercomparison: results of Czech participation

    International Nuclear Information System (INIS)

    Spurny, F.; Votockova, I.

    1996-01-01

    An international intercomparison scheme for criticality accident dosimetry systems took place at the SILENE reactor, Valduc, France in June 1993. The dosemeters were exposed both on phantoms and in free air to radiation from the reactor, both shielded by lead and bare. The results obtained during this event by Czech participants are presented and compared with the average values obtained by the complete group of participants and with the reference values. The systems used consisted mostly of Si-diodes and thermoluminescent detectors, some supporting measurements were performed with solid state nuclear track detectors and using the albedo principle. The agreement between the data sets is very good. 7 tabs., 13 refs

  11. Intercomparison of radionuclide measurements in marine sediment sample IAEA-368

    International Nuclear Information System (INIS)

    Ballestra, S.; Lopez, J.J.; Gastaud, J.; Parsi, P.; Vas, D.; Noshkin, V.

    1991-08-01

    The results of an intercomparison exercise on a Pacific Ocean sediment sample, IAEA-368, designed for the determination of artificial and natural radionuclides levels, are reported. The data from 89 laboratories representing 37 countries have been evaluated. The following are the recommended values, with confidence intervals, for 60 Co, 155 Eu, 210 7Pb, 226 Ra, 238 U, 238 Pu and 239+240 Pu (Reference date: 1 January 1990). Information values for 40 K, 90 Sr, 137 Cs, 228 Th, 230 Th, 232 Th, 234 U, 235 U and 241 Am are also reported. (author)

  12. Intercomparison of radionuclide measurements in marine sediment sample IAEA-367

    International Nuclear Information System (INIS)

    Ballestra, S.; Lopez, J.J.; Gastaud, J.; Vas, D.; Noshkin, V.

    1991-08-01

    The results of an intercomparison exercise on a Pacific Ocean sediment sample, IAEA-367, designed for the determination of artificial and natural radionuclides levels, are reported. The data from 81 laboratories representing 37 countries have been evaluated. The following are the recommended values, with confidence intervals, for 60 Co, 90 Sr, 137 Cs, 239+240 Pu (Reference date: 1 January 1990). Information values for 155 Eu, 238 Pu, 241 Am, and 241 Pu are reported. Information values for the following natural radionuclides 40 K, 226 Ra, 228 Th, 230 Th, 234 U, 235 U and 238 U are also reported. (author)

  13. Impact of Spatial Scales on the Intercomparison of Climate Scenarios

    Energy Technology Data Exchange (ETDEWEB)

    Luo, Wei; Steptoe, Michael; Chang, Zheng; Link, Robert; Clarke, Leon; Maciejewski, Ross

    2017-01-01

    Scenario analysis has been widely applied in climate science to understand the impact of climate change on the future human environment, but intercomparison and similarity analysis of different climate scenarios based on multiple simulation runs remain challenging. Although spatial heterogeneity plays a key role in modeling climate and human systems, little research has been performed to understand the impact of spatial variations and scales on similarity analysis of climate scenarios. To address this issue, the authors developed a geovisual analytics framework that lets users perform similarity analysis of climate scenarios from the Global Change Assessment Model (GCAM) using a hierarchical clustering approach.

  14. The inspirations with a radioactive intercomparison on a wine sample

    International Nuclear Information System (INIS)

    Su Qiong

    1993-12-01

    The methods used and results in a radioactive intercomparison on a wine sample are reported, which was organized by WHO-IRC in May, 1992. In order to analyse and compare the results obtained by all laboratories from WHO-IRC report (IRC NOTE No.41, 1993) are given. A re-measured new result about nuclide 40 K in the sample is also reported which coincides quite well with the result reported to IRC in a deviation of less than +-1%. And the problems concerning 'reference values' and standard sources etc. are also discussed

  15. Application of microwave cell system in calibration of electromagnetic field meters

    International Nuclear Information System (INIS)

    Abu-Kassem, I.

    2012-11-01

    The aim of this work is to improve radiation measurements of electromagnetic field (EMF) through realizing tests and calibrations of measurement devices by intercomparison within the microwaves (MW) range according to EMF wave cell properties. Actually, the calibration facility in electromagnetic field is not available in Syria; therefore, realizing an experimental system for electromagnetic field radiometer calibration is very important at national level. This study showed the possibility of using EMF wave cell in intercomparison of electromagnetic field radiometers in order to achieve a direct calibration via standard radiometer. The EMF wave cell properties were studied and the homogeneity of its EMF was tested using the EF Cube probe. Results showed that the field homogeneity inside the cell is good and the variation of electric field strength, within the comparison position, is less than 10% of measured values. It was recognized that the probe form and dimensions influence the comparison results; and measurement results showed that it's possible to achieve comparison in the working domain of EMF wave cell (10 - 3000 MHz) with a relative deviation of result values between 10% and 30% according to the measurement device and frequency range. Development of comparison process in order to obtain accurate results needs to improve mechanical supports of tested probes and to introduce a correction factor related to studied probe form and dimensions. From another side, it is better to carry out measurements at frequencies around the central frequency, and not close to frequency range borders, of the EMF wave cell working frequency domain. (author)

  16. RCA/IAEA third external dosimetry intercomparisons in East Asia region

    International Nuclear Information System (INIS)

    Yamamoto, H.; Yoshizawa, M.; Murakami, H.; Momose, T.; Tsujimura, N.; Kanai, K.; Cruz-Suarez, R.

    2007-01-01

    Several intercomparison exercises were organised by the International Atomic Energy Agency (IAEA) on the determination of operational quantities at the regional or inter-regional basis. In East Asia region, a third phase of the intercomparison finished in mid 2004. It was organised within the frame of the Regional Cooperation Agreement (RCA) as a follow-up to previous exercises carried out during 1990-1992 and 1995-1996. The results of this intercomparison for the determination of operational quantities were satisfactory for all Member States. The laboratories demonstrated a good performance in quantities tested. The purpose of this paper is to present the results of the RCA/IAEA intercomparison and the future of RCA activities in support of assessment of occupational exposure by organising intercomparison runs. (authors)

  17. Eurados self-sustained programme of intercomparisons for individual monitoring services

    International Nuclear Information System (INIS)

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

    2011-01-01

    Within EURADOS working group 2, a system for self-sustained intercomparisons for individual monitoring services for external radiation was developed. With the intercomparison results, the participants can show compliance within their quality management system, compare their results with those from other participants and develop plans for improvement of their system. The costs of the exercises are covered by the participants fees. In this programme, the first intercomparison exercise for whole-body dosemeters has been executed in 2008 with 62 participating dosimetry systems from participants across Europe. In general, film systems show the largest deviations, although the results of some participants indicate that it is possible to achieve results with a film system with similar quality as for thermoluminescence dosimetry (TLD) systems. A second intercomparison has been organised for extremity dosemeters in 2009. For 2010 it is planned to organise a second intercomparison for whole-body dosemeters. (authors)

  18. Single Camera Calibration in 3D Vision

    Directory of Open Access Journals (Sweden)

    Caius SULIMAN

    2009-12-01

    Full Text Available Camera calibration is a necessary step in 3D vision in order to extract metric information from 2D images. A camera is considered to be calibrated when the parameters of the camera are known (i.e. principal distance, lens distorsion, focal length etc.. In this paper we deal with a single camera calibration method and with the help of this method we try to find the intrinsic and extrinsic camera parameters. The method was implemented with succes in the programming and simulation environment Matlab.

  19. Participation of ARN-Argentina in the quality assessment program, EML-USDOE since 1995 to 1999

    International Nuclear Information System (INIS)

    Equillor, Hugo E.; Serdeiro, Nelida H.; Bonino, Nestor O.; Fernandez, Jorge A.; Gavini, Ricardo M.; Grinman, Ana D.R.; Lewis, E. Cecilia; Palacios, Miguel A.; Bomben, Ana M.; Diodati, Jorge M.

    2000-01-01

    A radiochemical laboratory must apply optimized analytical techniques and calibrated measurement systems so as to obtain accurate results. In order to achieve this, it is necessary to participate in intercomparison programs with specialized laboratories, as well as to have internal controls that must routinely be done, like efficiencies, backgrounds and chemical yields. The Nuclear Regulatory Authority, in charge of the radiological protection in the Argentine Republic, participates since 1995 in the Quality Assessment Program (QAP) carried out by the Environmental Measurements Laboratory-United States Department of Energy. The aim of this participation is to assess the quality of the reported measurements. The results of these ten partaking are detailed and analyzed in this work. (authors)

  20. Tour of the Standards and Calibrations Laboratory

    International Nuclear Information System (INIS)

    Elliott, J.H.

    1978-01-01

    This tour of Lawrence Livermore Laboratory's Standards and Calibrations Laboratory is intended as a guide to the capabilities of and services offered by this unique laboratory. Described are the Laboratory's ability to provide radiation fields and measurements for dosimeters, survey instruments, spectrometers, and sources and its available equipment and facilities. The tour also includes a survey of some Health Physics and interdepartmental programs supported by the Standards and Calibrations Laboratory and a listing of applicable publications

  1. Compact Optical Technique for Streak Camera Calibration

    International Nuclear Information System (INIS)

    Curt Allen; Terence Davies; Frans Janson; Ronald Justin; Bruce Marshall; Oliver Sweningsen; Perry Bell; Roger Griffith; Karla Hagans; Richard Lerche

    2004-01-01

    The National Ignition Facility is under construction at the Lawrence Livermore National Laboratory for the U.S. Department of Energy Stockpile Stewardship Program. Optical streak cameras are an integral part of the experimental diagnostics instrumentation. To accurately reduce data from the streak cameras a temporal calibration is required. This article describes a technique for generating trains of precisely timed short-duration optical pulses that are suitable for temporal calibrations

  2. Report on the intercomparison run for the determination of radionuclides in soils. IAEA-326 and IAEA-327

    International Nuclear Information System (INIS)

    Bojanowski, R.; Radecki, Z.; Campbell, M.J.; Burns, K.I.; Trinkl, A.

    2001-04-01

    Intercomparison programmes have the potential to improve the level of agreement between the results of measurements obtained on natural matrices by different methods and by various laboratories world-wide. They could also be able to help the participants trace the causes of departure of their data from the true values, if sufficient information is provided to the organiser. As the true values are unknown, they are usually replaced by consensus values derived from the data that have met a number of defined quality criteria. The previous evaluation process of intercomparison exercises did not allow the full benefits of exercise to be obtained. The reference values were set on the basis of 'the law of the majority' ('consensus' values) and were not traceable to internationally agreed primary units (SI units). Traceability of measurements can be achieved by providing a link between the data generated in participants' laboratories and a stipulated reference point through an unbroken chain of comparisons, enabling assessment of the quality of their measurements by quantifying the combined uncertainty of all the links in the chain. In radioactivity measurements, the shortest chain is achieved in γ-spectrometry. It can be obtained by proper calibration of instruments, using standard sources certified by primary measurement laboratories and propagating the uncertainties throughout the whole measurement process. Matrix effects and coincidence losses must be given due attention as well. Traceability of results obtained by isotope dilution alpha- spectrometry requires, in addition, a quantitative budget of uncertainties associated with sample treatment up to the stage when isotope exchange is assured. The most difficult cases are methods based on beta counting because each stage of the numerous analytical operations can break the traceability chain and because beta-radiation has a continuous spectrum which is difficult to quantify. In this Intercomparison, an attempt was made

  3. Calibration of moisture monitors

    International Nuclear Information System (INIS)

    Gutierrez, R.L.

    1979-02-01

    A method for calibrating an aluminum oxide hygrometer against an optical chilled mirror dew-point hygrometer has been established. A theoretical cross-point line of dew points from both hygrometers and a maximum moisture content of 10 ppM/sub v/ are used to define an area for calibrating the sensor probes of the aluminum oxide hygrometer

  4. Site Calibration report

    DEFF Research Database (Denmark)

    Yordanova, Ginka; Vesth, Allan

    The report describes site calibration measurements carried out on a site in Denmark. The measurements are carried out in accordance to Ref. [1]. The site calibration is carried out before a power performance measurement on a given turbine to clarify the influence from the terrain on the ratio...

  5. Topics in Statistical Calibration

    Science.gov (United States)

    2014-03-27

    Natural cubic spline speed di st 110 B.2 The calibrate function The most basic calibration problem, the one often encountered in more advanced ...0040-1706, 1537-2723. A. M. Mood, F. A. Graybill, and D. C. Boes. Introduction to the Theory of Statistics. McGraw-Hill, Auckland , U.A, 1974. ISBN

  6. BIPM project: Intercomparison of water triple-point cells

    Science.gov (United States)

    Chattle, M. V.; Butler, J.

    1994-12-01

    The paper presents the results of an intercomparison between 3 triple point of water cells circulated by the Bureau International des Poids et Measures (BIPM), and a cell which is one of those used as a reference cell at the National Physical Laboratory (NPL). All 4 cells were prepared, stored and measured in the manner normally adopted at NPL. The results of the intercomparison show that over the course of about 6 weeks the temperatures of the 3 circulated cells generally agreed within 0.20 mK, with a maximum difference of 0.27(7) mK. Over the same period, the total variations of temperature measured in the 3 individual cells were 0.04 mK, 0.08 mK and 0.18 mK, respectively; the NPL cell varied by 0.10 mK. Gallium point measurements made over a similar period confirmed that these differences were partly due to small drifts in the thermometer resistance or in the measuring system.

  7. PIDIE, plutonium isotopic determination inter-comparison exercise

    International Nuclear Information System (INIS)

    Harry, R.J.S.

    1990-07-01

    PIDIE (Plutonium Isotopic Determination Inter-comparison Exercise) is one of the projects of the ESARDA Working Group on Techniques and Standards for Non-Destructive Analysis. PIDIE is placed against the historical background of the general development of international standards. Its results are also reviewed in the light of the original purpose of the project. Sets of seven sealed Pu samples of different isotopic composition, each containing 0,45 grammes, were sent to the 9 participating laboratories for three separate determinations of the unknown isotopic composition, to investigate error sources and , if possible to improve the knowledge of γ-emission probabilities. An additional question was to examine the possible improvement of such measurements using reference samples. No important bias has been observed in the results of this inter-comparison. The apparent improvement in the precision and accuracy of the result seems to arise from both better equipment and more elaborate spectrum evaluation methods. (author). 39 refs.; 1 fig.; 5 tabs

  8. International codes and model intercomparison for intermediate energy activation yields

    International Nuclear Information System (INIS)

    Rolf, M.; Nagel, P.

    1997-01-01

    The motivation for this intercomparison came from data needs of accelerator-based waste transmutation, energy amplification and medical therapy. The aim of this exercise is to determine the degree of reliability of current nuclear reaction models and codes when calculating activation yields in the intermediate energy range up to 5000 MeV. Emphasis has been placed for a wide range of target elements ( O, Al, Fe, Co, Zr and Au). This work is mainly based on calculation of (P,xPyN) integral cross section for incident proton. A qualitative description of some of the nuclear models and code options employed is made. The systematics of graphical presentation of the results allows a quick quantitative measure of agreement or deviation. This code intercomparison highlights the fact that modeling calculations of energy activation yields may at best have uncertainties of a factor of two. The causes of such discrepancies are multi-factorial. Problems are encountered which are connected with the calculation of nuclear masses, binding energies, Q-values, shell effects, medium energy fission and Fermi break-up. (A.C.)

  9. Preliminary results of the alpha particle registration intercomparison ALRIT

    International Nuclear Information System (INIS)

    Paretzke, H.G.

    1976-01-01

    In view of the widespread interest in alpha particle registration with solid state nuclear track detectors, an international intercomparison of such measurements has been arranged. Sixteen sets of fourteen detectors each were sent to GSF-Neuherberg, there irradiated carefully with different alpha particle fields, and then returned for evaluation. Fourteen irradiation runs were made for each set simulating seven different irradiation situations commonly encountered in practical applications. The preliminary results of this intercomparison reported in this paper are based on the results of eight sets. They show good agreement with respect to the determination of track densities in the case of vertical incident alpha particles. Also the results obtained for determination of particle energies and angle of incidence in most cases were rather accurate. However, apparently it is still rather difficult to determine accurately and precisely the specific activity of alpha emitters on a thick filter positioned at some distance, i.e. for the case of 2π-incidence and a broad energy spectrum. (orig.) [de

  10. Intercomparison 2003 for Radon measurement services at PSI

    CERN Document Server

    Butterweck, G

    2003-01-01

    Twelve radon measurement services participated in the 2003 Radon Intercomparison Exercise performed at the Reference Laboratory for Radon Gas Activity Concentration Measurements at Paul Scherrer Institut (PSI) during March 13th to 24th, 2003. Ten of these laboratories were approved by the Swiss Federal Office of Public Health and their participation in the intercomparison exercise was a requirement to warrant quality of measurement. Radon gas detectors (etched-track and electret ionisation chambers) and instruments (ionisation chambers and electrostatic precipitation) were exposed in the PSI Radon Chamber in a reference atmosphere with an average radon gas concentration of 1950 Bqm sup - sup 3 leading to a radon gas exposure of 517 kBqhm sup - sup 3. Additional five electret-detectors of an approved measuring service were purchased by the Swiss Federal Office of Public Health for a spot check. Two of these were exposed as described above, two had an exposure of 247 kBqhm sup - sup 3 at an average radon concen...

  11. In-situ gammaspectrometry intercomparison exercise in Salzburg/Austria

    International Nuclear Information System (INIS)

    Steger, F.; Lovranich, E.; Lettner, H.; Andrasi, A.

    1996-01-01

    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 24 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. (author)

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

    Directory of Open Access Journals (Sweden)

    F. Pattyn

    2012-05-01

    Full Text Available 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.

  13. Extremity ring dosimetry intercomparison in reference and workplace fields

    International Nuclear Information System (INIS)

    Ginjaume, M.; Carinou, E.; Donadille, L.; Jankowski, J.; Rimpler, A.; Sans Merce, M.; Vanhavere, F.; Denoziere, M.; Daures, J.; Bordy, J. M.; Itie, C.; Covens, P.

    2008-01-01

    An intercomparison of ring dosemeters has been organised with the aim of assessing the technical capabilities of available extremity dosemeters and focusing on their performance at clinical workplaces with potentially high extremity doses. Twenty-four services from 16 countries participated in the intercomparison. The dosemeters were exposed to reference photon ( 137 Cs) and beta ( 147 Pm, 85 Kr and 90 Sr/ 90 Y) fields together with fields representing realistic exposure situations in interventional radiology (direct and scattered radiation) and nuclear medicine ( 99m Tc and 18 F). It has been found that most dosemeters provided satisfactory measurements of H p (0.07) for photon radiation, both in reference and realistic fields. However, only four dosemeters fulfilled the established requirements for all radiation qualities. The main difficulties were found for the measurement of low-energy beta radiation. Finally, the results also showed a general under-response of detectors to 18 F, which was attributed to the difficulties of the dosimetric systems to measure the positron contribution to the dose. (authors)

  14. Sandia WIPP calibration traceability

    Energy Technology Data Exchange (ETDEWEB)

    Schuhen, M.D. [Sandia National Labs., Albuquerque, NM (United States); Dean, T.A. [RE/SPEC, Inc., Albuquerque, NM (United States)

    1996-05-01

    This report summarizes the work performed to establish calibration traceability for the instrumentation used by Sandia National Laboratories at the Waste Isolation Pilot Plant (WIPP) during testing from 1980-1985. Identifying the calibration traceability is an important part of establishing a pedigree for the data and is part of the qualification of existing data. In general, the requirement states that the calibration of Measuring and Test equipment must have a valid relationship to nationally recognized standards or the basis for the calibration must be documented. Sandia recognized that just establishing calibration traceability would not necessarily mean that all QA requirements were met during the certification of test instrumentation. To address this concern, the assessment was expanded to include various activities.

  15. Sandia WIPP calibration traceability

    International Nuclear Information System (INIS)

    Schuhen, M.D.; Dean, T.A.

    1996-05-01

    This report summarizes the work performed to establish calibration traceability for the instrumentation used by Sandia National Laboratories at the Waste Isolation Pilot Plant (WIPP) during testing from 1980-1985. Identifying the calibration traceability is an important part of establishing a pedigree for the data and is part of the qualification of existing data. In general, the requirement states that the calibration of Measuring and Test equipment must have a valid relationship to nationally recognized standards or the basis for the calibration must be documented. Sandia recognized that just establishing calibration traceability would not necessarily mean that all QA requirements were met during the certification of test instrumentation. To address this concern, the assessment was expanded to include various activities

  16. The use of a secondary standard x-ray exposure meter to calibrate a field instrument for use in output measurements

    International Nuclear Information System (INIS)

    1974-11-01

    It is stated that the recommended procedures have been closely correlated with ICRU Report 23 (1973), 'Measurements of absorbed dose in a phantom irradiated by a single beam of X- or gamma-rays'. The present report is contained in sections entitled: introduction; equipment and outline of procedures; calibration and use of field instrument in a phantom; calibration and use of the field instrument in air; local reference instrument; summary of recommended procedures. Appendices are entitled: the Perspex Intercomparison Phantom; the implications of applying an in-air calibration factor to readings made in a water phantom. (U.K.)

  17. Advisory Committee for the Calibration Standards of Ionizing Radiation Measurement

    International Nuclear Information System (INIS)

    1982-01-01

    An account of the activity during the past two years and of the plans for future work is given for the three Sections of the Comite Consultatif pour les Etalons de Mesure des Rayonnements Ionisants. Section I (Rayons X et #betta#, electrons) studied in detail the results of an intercomparison of Frike dosimeters. A recommendation was made concerning the possibility of expressing calibrations made in terms of exposure in terms of air kerma or water kerma. Section II (Mesure des radionucleides) studied the results of recent international comparisons ( 55 Fe, 133 Ba and 134 Cs) and made plans for new ones. Section III (Mesures neutroniques) presented the status of the international comparisons of neutron fluence rate in progress and decided to organize new ones. The reports of the Section chairmen are followed by the presentation of the work carried out at BIPM by the corresponding groups. The status of the proposal by Section III for a 14 MeV neutron dosimetry facility at BIPM is discussed in detail and a proposal is made for a neutron dosimetry intercomparison [fr

  18. Analysis of results from intercomparison among Spanish laboratories involved of photon energy ''137 Cs for environmental dosimetry laboratories

    International Nuclear Information System (INIS)

    Gonzalez, A.M.; Brosed, A.; Salas, R.

    2003-01-01

    Any environmental thermoluminescent dosemeter (TLD) system must be periodically calibrated at a calibration laboratory. In this frame, the Consejo de Seguridad Nuclear (CSN) has performed an intercomparison among Spanish laboratories involved in environmental monitoring, by means of TLD, in order to verify the traceability of the whole dosimeter and reader to the national standard for the protection quantities of interest for a given photon energy (''137Cs). To achieve this goal the CSN asked the Centro de Investigaciones Energeticas, Medioambientales y Tecnologicas (CIEMAT) to carry out the reference irradiations in the energy above mentioned at the lonising Radiations Metrology Unit headquarters. Nine laboratories have participated. All the dosemeters were irradiated with the same air kerma rate. The radiological quantity used was the ambient dose equivalent, H (10), and the values of this quantity assigned to each laboratory were between 210 and 360 μSv. All the dosemeters of the participating laboratories met the two analysis criteria used. All of them demonstrated a satisfactory fulfilment of the requirements established by so called trumpet curves and of the requirements established by the ANSI 1311. (Author) 7 refs

  19. The Norwegian UV-monitoring program. Period 1995/96 to 2001

    Energy Technology Data Exchange (ETDEWEB)

    Johnsen, Bjoern; Mikkelborg, Oddbjoern; Hannevik, Merete; Nilsen, Lill Tove; Saxeboel, Gunnar; Blaasaas, Karl Gerhard

    2002-07-01

    The report describes the program and results obtained during the period 1995 to 2001. The UV monitoring is performed at 8 locations between 58 {sup o} N and 79 {sup o} N. The experiments with the network implementation and operation are very good. Calibrations are traceable to several European UV networks, through the Nordic Intercomparison of UV and total ozone instruments in Sweden 2000. The measurements have been validated and found consistent. Six years of complete series of daily integrated erythemally effective UV-radiation (denoted UV-doses for short) and UV-indices are available for public and scientific use. The measurement series are yet too short to infer any trend in the UV-radiation. The Norwegian Institute provides UV-forecasts for air research (Author)

  20. 1987 Neutron and gamma personnel dosimeter intercomparison study using a D2O-moderated 252Cf source

    International Nuclear Information System (INIS)

    Swaja, R.E.; West, L.E.; Sims, C.S.; Welty, T.J.

    1989-05-01

    The thirteenth Personnel Dosimetry Intercomparison Study (i.e., PDIS 13) was conducted during April 1987 as a joint effort by Oak Ridge National Laboratory's (ORNL) Dosimetry Applications Research Group and the Southwest Radiation Calibration Center at the University of Arkansas. A total of 48 organizations (34 from the US and 14 from abroad) participated in PDIS 13. Participants submitted a total of 1,113 neutron and gamma dosimeters for this mixed field study. The dosimeters were transferred by mail and were handled by experimental personnel at ORNL and the University of Arkansas. The type of neutron dosimeter and the percentage of participants submitting that type are as follows: TLD-albedo (49%), direct interaction TLD (31%), CR-39 (17%), film (3%). The type of gamma dosimeter and the percentage of participants submitting that type are as follows: Li 2 B 4 O 7 , alone or in combination with CaSO 4 , (69%), 7 LiF (28%), natural LiF (3%). Radiation exposures in PDIS 13 were limited to 0.5 and 1.5 mSv from 252 Cf moderated by 15-cm of D 2 O. Traditional exposures using the Health Physics Research Reactor (HPRR) were not possible due to the fact that all reactors at ORNL, including the HPRR, were shutdown by order of the Department of Energy at the time the intercomparison was performed. Planned exposures using a 238 PuBe source were negated by a faulty timing mechanism. Based on accuracy and precision, direct interaction TLD dosimeters exhibited the best performance in PDIS 13 neutron measurements. They were followed, in order of best performance, by CR-39, TLD albedo, and film. The Li 2 B 4 O 7 type TLD dosimeters exhibited the best performance in PDIS 13 gamma measurements. They were followed by natural LiF, 7 LiF, and film. 12 refs., 1 fig., 5 tabs

  1. Compact radiometric microwave calibrator

    International Nuclear Information System (INIS)

    Fixsen, D. J.; Wollack, E. J.; Kogut, A.; Limon, M.; Mirel, P.; Singal, J.; Fixsen, S. M.

    2006-01-01

    The calibration methods for the ARCADE II instrument are described and the accuracy estimated. The Steelcast coated aluminum cones which comprise the calibrator have a low reflection while maintaining 94% of the absorber volume within 5 mK of the base temperature (modeled). The calibrator demonstrates an absorber with the active part less than one wavelength thick and only marginally larger than the mouth of the largest horn and yet black (less than -40 dB or 0.01% reflection) over five octaves in frequency

  2. Lidar to lidar calibration

    DEFF Research Database (Denmark)

    Fernandez Garcia, Sergio; Villanueva, Héctor

    This report presents the result of the lidar to lidar calibration performed for ground-based lidar. Calibration is here understood as the establishment of a relation between the reference lidar wind speed measurements with measurement uncertainties provided by measurement standard and corresponding...... lidar wind speed indications with associated measurement uncertainties. The lidar calibration concerns the 10 minute mean wind speed measurements. The comparison of the lidar measurements of the wind direction with that from the reference lidar measurements are given for information only....

  3. Outline of the 1996-1998 IAEA co-ordinated research project on intercomparison for individual monitoring of external exposure from photon radiation

    International Nuclear Information System (INIS)

    Boehm, J.; Gustafsson, M.; Ouvrard, R.

    1999-01-01

    The outline of the IAEA Co-ordinated Research Project 1996-1998 on intercomparison for individual monitoring is described. The intercomparison focused on IAEA Member States in Eastern Europe and was based on the operational quantity personal dose equivalent, H p (10). The three phases of the intercomparison were: the preparatory phase including a workshop, the 'type-test' intercomparison, and the 'simulated workplace field' intercomparison. Details of the phases are given. (author)

  4. Monitoring coordinate measuring machines by calibrated parts

    International Nuclear Information System (INIS)

    Weckenmann, A; Lorz, J

    2005-01-01

    Coordinate measuring machines (CMM) are essential for quality assurance and production control in modern manufacturing. Due to the necessity of assuring traceability during the use of CMM, interim checks with calibrated objects carried out periodically. For this purpose usually special artefacts like standardized ball plates, hole plates, ball bars or step gages are measured. Measuring calibrated series parts would be more advantageous. Applying the substitution method of ISO 15530-3: 2000 such parts can be used. It is less cost intensive and less time consuming than measuring expensive special standardized objects in special programmed measurement routines. Moreover, the measurement results can directly compare with the calibration values; thus, direct information on systematic measurement deviations and uncertainty of the measured features are available. The paper describes a procedure for monitoring horizontal-arm CMMs with calibrated sheet metal series parts

  5. Lessons learnt from participation in international inter-comparison exercise for environmental radioactivity measurement

    International Nuclear Information System (INIS)

    Jha, S.K.; Pulhani, Vandana; Sartandel, Sangeeta

    2016-06-01

    Environmental Radioactivity Measurement Section of Health Physics Division is regularly carrying out surveillance of the radioactivity concentration in the environment. The laboratory participates in the inter-comparison exercises conducted by various international agencies for quality assurance and quality control of analytical estimations. This report summarizes the results of the analysis of radioactivity in environmental matrices of the inter-comparison exercises. The participation in inter-comparison exercises has demonstrated competence in radionuclide identification and estimations, equivalence with the results of other participating laboratories, validated adopted analytical methods, introduced traceability to measurement etc. at national and international level. (author)

  6. Nuclear accident dosimetry, Report on the Third IAEA intercomparison experiment at Vinca, Yugoslavia

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1977-03-15

    The objective of this report is to present the results of the third IAEA intercomparison experiment held at the Boris Kidric Institute, Vinca, in May 1973. These experiments were a part of multi laboratory intercomparison programme sponsored by the IAEA for evaluation of nuclear accident dosimetry systems that ought to provide adequate information in the event of criticality accidents. This report deals with the data concerning the Third intercomparison experiments in which the RB reactor at Vinca was used as a source of mixed radiation.

  7. International intercomparison on the neutron flux density spectrum just before the REAL-80 project

    International Nuclear Information System (INIS)

    Ertek, C.

    1981-06-01

    This work briefly presents the results of the international intercomparison on the neutron flux density spectrum just before the REAL-80 intercomparison project. Some of the results of this intercomparison with a smaller number of laboratories will be also reflected in the REAL-80 project, therefore, it has some significant issues. This work is performed within the IAEA programme on standardization of reactor radiation measurements, one of the important objectives of which is the assistance of laboratories in Member States to implement or intercompare the multiple foil activation techniques for different neutron field measurements

  8. Report on intercomparison exercise SR-54. Determination of impurities in U3O8

    International Nuclear Information System (INIS)

    Doubek, N.; Bagliano, G.; Deron, S.

    1984-04-01

    The report presents results of a laboratory intercomparison of impurities in U 3 O 8 sample organized by the IAEA's Analytical Quality Control Service. Twelve laboratories in 11 countries sent their results. The framework of the intercomparison was therefore conceived mainly as a ''mean'' to laboratories dealing with analysis of impurities in uranium samples to check the reliability of their results. The evaluation was based on 97 laboratory means obtained with emission spectroscopy, atomic absorption techniques and neutron activation analysis. The concentration of three elements could be certified as a result of this intercomparison; informational values could be established for an additional six elements

  9. Air Data Calibration Facility

    Data.gov (United States)

    Federal Laboratory Consortium — This facility is for low altitude subsonic altimeter system calibrations of air vehicles. Mission is a direct support of the AFFTC mission. Postflight data merge is...

  10. SRHA calibration curve

    Data.gov (United States)

    U.S. Environmental Protection Agency — an UV calibration curve for SRHA quantitation. This dataset is associated with the following publication: Chang, X., and D. Bouchard. Surfactant-Wrapped Multiwalled...

  11. BES online calibration system

    International Nuclear Information System (INIS)

    Zhang Bingyun; Li Xiaonan; Zhu Kejun; Zhang Jiawen; Gong Mingyu

    2003-01-01

    We constructed BES (Beijing Spectrometer) online calibration system to ensure the coherence of readout electronic channels due to huge data volume in high energy physics experiment. This paper describes the structure of hardware and software, and its characteristic and function

  12. Calibrated Properties Model

    International Nuclear Information System (INIS)

    Ahlers, C.F.; Liu, H.H.

    2001-01-01

    The purpose of this Analysis/Model Report (AMR) is to document the Calibrated Properties Model that provides calibrated parameter sets for unsaturated zone (UZ) flow and transport process models for the Yucca Mountain Site Characterization Project (YMP). This work was performed in accordance with the AMR Development Plan for U0035 Calibrated Properties Model REV00 (CRWMS M and O 1999c). These calibrated property sets include matrix and fracture parameters for the UZ Flow and Transport Model (UZ Model), drift seepage models, drift-scale and mountain-scale coupled-processes models, and Total System Performance Assessment (TSPA) models as well as Performance Assessment (PA) and other participating national laboratories and government agencies. These process models provide the necessary framework to test conceptual hypotheses of flow and transport at different scales and predict flow and transport behavior under a variety of climatic and thermal-loading conditions

  13. Calibrated Properties Model

    International Nuclear Information System (INIS)

    Ahlers, C.; Liu, H.

    2000-01-01

    The purpose of this Analysis/Model Report (AMR) is to document the Calibrated Properties Model that provides calibrated parameter sets for unsaturated zone (UZ) flow and transport process models for the Yucca Mountain Site Characterization Project (YMP). This work was performed in accordance with the ''AMR Development Plan for U0035 Calibrated Properties Model REV00. These calibrated property sets include matrix and fracture parameters for the UZ Flow and Transport Model (UZ Model), drift seepage models, drift-scale and mountain-scale coupled-processes models, and Total System Performance Assessment (TSPA) models as well as Performance Assessment (PA) and other participating national laboratories and government agencies. These process models provide the necessary framework to test conceptual hypotheses of flow and transport at different scales and predict flow and transport behavior under a variety of climatic and thermal-loading conditions

  14. SPOTS Calibration Example

    Directory of Open Access Journals (Sweden)

    Patterson E.

    2010-06-01

    Full Text Available The results are presented using the procedure outlined by the Standardisation Project for Optical Techniques of Strain measurement to calibrate a digital image correlation system. The process involves comparing the experimental data obtained with the optical measurement system to the theoretical values for a specially designed specimen. The standard states the criteria which must be met in order to achieve successful calibration, in addition to quantifying the measurement uncertainty in the system. The system was evaluated at three different displacement load levels, generating strain ranges from 289 µstrain to 2110 µstrain. At the 289 µstrain range, the calibration uncertainty was found to be 14.1 µstrain, and at the 2110 µstrain range it was found to be 28.9 µstrain. This calibration procedure was performed without painting a speckle pattern on the surface of the metal. Instead, the specimen surface was prepared using different grades of grit paper to produce the desired texture.

  15. Introduction The Role of the Agricultural Model Intercomparison and Improvement Project

    Science.gov (United States)

    Rosenzweig, Cynthia; Hillel, Daniel

    2015-01-01

    Climate impacts on agriculture are of increasing concern in both the scientific and policy communities because of the need to ensure food security for a growing population. A special challenge is posed by the changes in the frequency and intensity of heat-waves, droughts, and episodic rainstorms already underway in many parts of the world. Changes in production are directly linked to such variations in temperature and precipitation during the growing season, and often to offseason changes in weather affecting soil-water storage and availability to crops. This is not an isolated problem but one of both global and regional importance, because of impacts on the livelihoods of smallholder farmers as well as consequences for the world food trade system. This two-part set the Agricultural Model Intercomparison and Improvement Project (AgMIP): Integrated Crop and Economic Assessments is the first to be entirely devoted to AgMIP (www.agmip.org). AgMIP is a major international research program focused on climate change and agriculture. The goal of the two parts is to advance the field by providing detailed information on new simulation techniques and assessments being conducted by this program. It presents information about new methods of global and regional integrated assessment, results from agricultural regions, and adaptation strategies for maintaining food security under changing climate conditions.

  16. Intercomparison of preliminary MFR, SBUV, TOMS, and TOVS total ozone data

    International Nuclear Information System (INIS)

    Luther, F.M.

    1992-01-01

    The High Altitude Pollution Program of the Federal Aviation Administration is sponsoring a comparative study of total ozone data derived from various satellite instruments. The instruments included in the study are the Defense Meteorological Satellite Program's Multichannel Filter Radiometer (MFR), the NASA Solar Backscatter Ultraviolet Ozone Experiment (SBUV), the NASA Total Ozone Mapping Spectrometer (TOMS), and the NOAA Tiros Operational Vertical Sounder (TOVS). The two periods chosen for data intercomparison are January 1 - February 15, 1979 and June 1-30, 1979. These two data periods cover summer and winter regimes in both hemispheres. The January 1 - February 15, 1979 period includes a significant stratospheric warming event that began about January 15. Each of the satellite instruments has its own strengths and weaknesses. No instrument is universally better than or worse than any other in terms of accuracy, although they appear to have definite biases in certain geographical areas. The differences between the satellite systems is greatest at high latitudes where cloudiness and ozone variabilities are greatest. The Dobson data show a bias and differing degrees of ozone variability between nearby Dobson stations, which indicates there may be problems with using the Dobson data as a standard for comparison. The data used in this comparative study are preliminary in nature

  17. Calibration of Photon Sources for Brachytherapy

    Science.gov (United States)

    Rijnders, Alex

    Source calibration has to be considered an essential part of the quality assurance program in a brachytherapy department. Not only it will ensure that the source strength value used for dose calculation agrees within some predetermined limits to the value stated on the source certificate, but also it will ensure traceability to international standards. At present calibration is most often still given in terms of reference air kerma rate, although calibration in terms of absorbed dose to water would be closer to the users interest. It can be expected that in a near future several standard laboratories will be able to offer this latter service, and dosimetry protocols will have to be adapted in this way. In-air measurement using ionization chambers (e.g. a Baldwin—Farmer ionization chamber for 192Ir high dose rate HDR or pulsed dose rate PDR sources) is still considered the method of choice for high energy source calibration, but because of their ease of use and reliability well type chambers are becoming more popular and are nowadays often recommended as the standard equipment. For low energy sources well type chambers are in practice the only equipment available for calibration. Care should be taken that the chamber is calibrated at the standard laboratory for the same source type and model as used in the clinic, and using the same measurement conditions and setup. Several standard laboratories have difficulties to provide these calibration facilities, especially for the low energy seed sources (125I and 103Pd). Should a user not be able to obtain properly calibrated equipment to verify the brachytherapy sources used in his department, then at least for sources that are replaced on a regular basis, a consistency check program should be set up to ensure a minimal level of quality control before these sources are used for patient treatment.

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

    International Nuclear Information System (INIS)

    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 ±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

  19. Looking beyond general metrics for model comparison - lessons from an international model intercomparison study

    Science.gov (United States)

    de Boer-Euser, Tanja; Bouaziz, Laurène; De Niel, Jan; Brauer, Claudia; Dewals, Benjamin; Drogue, Gilles; Fenicia, Fabrizio; Grelier, Benjamin; Nossent, Jiri; Pereira, Fernando; Savenije, Hubert; Thirel, Guillaume; Willems, Patrick

    2017-01-01

    International collaboration between research institutes and universities is a promising way to reach consensus on hydrological model development. Although model comparison studies are very valuable for international cooperation, they do often not lead to very clear new insights regarding the relevance of the modelled processes. We hypothesise that this is partly caused by model complexity and the comparison methods used, which focus too much on a good overall performance instead of focusing on a variety of specific events. In this study, we use an approach that focuses on the evaluation of specific events and characteristics. Eight international research groups calibrated their hourly model on the Ourthe catchment in Belgium and carried out a validation in time for the Ourthe catchment and a validation in space for nested and neighbouring catchments. The same protocol was followed for each model and an ensemble of best-performing parameter sets was selected. Although the models showed similar performances based on general metrics (i.e. the Nash-Sutcliffe efficiency), clear differences could be observed for specific events. We analysed the hydrographs of these specific events and conducted three types of statistical analyses on the entire time series: cumulative discharges, empirical extreme value distribution of the peak flows and flow duration curves for low flows. The results illustrate the relevance of including a very quick flow reservoir preceding the root zone storage to model peaks during low flows and including a slow reservoir in parallel with the fast reservoir to model the recession for the studied catchments. This intercomparison enhanced the understanding of the hydrological functioning of the catchment, in particular for low flows, and enabled to identify present knowledge gaps for other parts of the hydrograph. Above all, it helped to evaluate each model against a set of alternative models.

  20. Report on the intercomparison run F-1 U and K(Th) in feldspar

    International Nuclear Information System (INIS)

    1990-01-01

    The present report deals with a recent intercomparison on the determination of uranium, thorium and potassium in potassium feldspar, carried out in 1976-77 and involving the participation of 20 institutes who returned a total of 196 individual results on three elements. Analytical techniques employed by the participating institutes included gamma spectrometry, emission spectroscopy, atomic absorption, X-ray fluorescence, fluorimetry and neutron activation. Each of these techniques has its own particular weakness: The basic principles of gamma-spectrometric technique for the determination of U, Th and K are well known. It is, however, difficult to determine the low concentrations of radioactive nuclides which can be found in geological materials due to systematic errors arising from non-equilibration of decay chains in the samples and from other sources including calibration. Determination of uranium in geological materials by non-destructive neutron activation analysis also has some problems. Elements such as Th, Ta, Pt, Ru, Zn and Ba when irradiated in a nuclear reactor with thermal and epithermal neutrons yield radioactive isotopes, the gamma rays of which interfere with those used in uranium determination. Detection limits for three elements U, Th and K for thermal neutron activation have been reported as 0.7, 1.0 and 10 ppb respectively, however, this seems over-optimistic to expect in real-life situations. Measurement of delayed neutrons and fission track methods for uranium and thorium also have interference problems. Fluorimetry is a suitable method for uranium at low concentrations (down to 0.1 ppm) but one has to take care to overcome quenching by removing, or at least diluting, interfering elements. The determination of some important elements in geochemical samples is often difficult because of their small concentration as well as of the presence of interfering matrix elements in the samples. Some systematic differences seem to exist between the methods

  1. Instruments to measure radon-222 activity concentration or exposure to radon-222. Intercomparison 2014

    International Nuclear Information System (INIS)

    Foerster, Elisabeth; Beck, Thomas; Buchroeder, Helmut; Doering, Joachim; Schmidt, Volkmar

    2014-10-01

    According to the Directive 96/29/EURATOM the monitoring of occupational radiation exposures shall base on individual measurements carried out by an approved dosimetric service. Pursuant to the European Directive an approved dosimetric service is a body responsible for the calibration, reading or interpretation of individual monitoring devices.., whose capacity to act in this respect is recognized by the competent authorities. This concept will also be applied to radon services issuing passive radon measurement devices. Passive radon measurement devices 1 using solid state nuclear track detectors or electrets are recommended for individual monitoring of exposures to radon. German regulations lay down that radon measuring devices are appropriate for purposes of occupational radiation monitoring if the devices are issued by recognized radon measurement services, and the measurement service submits devices of the same type issued for radon monitoring to regular intercomparisons conducted by the Bundesamt fuer Strahlenschutz (BfS). A radon measuring service is recognized by the competent authority if it proves its organisational and technical competence, e. g. by accreditation. These regulations have been introduced in the area of occupational radiation exposures. Nevertheless, it is recommended that radon measuring services which carry out radon measurements in other areas (e.g. dwellings) should subject themselves to these measures voluntarily. The interlaboratory comparisons comprise the organization, exposure, and evaluation of measurements of radon activity concentration or exposure to radon. The comparisons only concern radon-222; radon-220 is not in the scope. Radon services being interested can get further information from the European Information System on Proficiency Testing Schemes (EPTIS) and from the BfS websites.

  2. Scanner calibration revisited

    Directory of Open Access Journals (Sweden)

    Pozhitkov Alexander E

    2010-07-01

    Full Text Available Abstract Background Calibration of a microarray scanner is critical for accurate interpretation of microarray results. Shi et al. (BMC Bioinformatics, 2005, 6, Art. No. S11 Suppl. 2. reported usage of a Full Moon BioSystems slide for calibration. Inspired by the Shi et al. work, we have calibrated microarray scanners in our previous research. We were puzzled however, that most of the signal intensities from a biological sample fell below the sensitivity threshold level determined by the calibration slide. This conundrum led us to re-investigate the quality of calibration provided by the Full Moon BioSystems slide as well as the accuracy of the analysis performed by Shi et al. Methods Signal intensities were recorded on three different microarray scanners at various photomultiplier gain levels using the same calibration slide from Full Moon BioSystems. Data analysis was conducted on raw signal intensities without normalization or transformation of any kind. Weighted least-squares method was used to fit the data. Results We found that initial analysis performed by Shi et al. did not take into account autofluorescence of the Full Moon BioSystems slide, which led to a grossly distorted microarray scanner response. Our analysis revealed that a power-law function, which is explicitly accounting for the slide autofluorescence, perfectly described a relationship between signal intensities and fluorophore quantities. Conclusions Microarray scanners respond in a much less distorted fashion than was reported by Shi et al. Full Moon BioSystems calibration slides are inadequate for performing calibration. We recommend against using these slides.

  3. Calibration of thermoluminiscent materials

    International Nuclear Information System (INIS)

    Bos, A.J.J.

    1989-07-01

    In this report the relation between exposure and absorbed radiation dose in various materials is represented, on the base of recent data. With the help of this a calibration procedure for thermoluminescent materials, adapted to the IRI radiation standard is still the exposure in rontgen. In switching to the air kerma standard the calibration procedure will have to be adapted. (author). 6 refs.; 4 tabs

  4. Intercomparison of radionuclide measurements in marine sediment sample IAEA-135

    International Nuclear Information System (INIS)

    Ballestra, S.; Gastaud, J.; Lopez, J.J.; Parsi, P.; Vas, D.

    1993-08-01

    The results of an intercomparison exercise on a marine sediment from Irish Sea, IAEA-135, designed for the determination of artificial and natural radionuclides levels, are reported. The data from 151 laboratories representing 51 countries have been evaluated. The following are the recommended values, with confidence intervals, for 40 K, 60 Co, 134 Cs, 137 Cs, 154 Eu, 155 Eu, 226 Ra, 228 Ra, 232 Th, 238 Pu, 239+240 Pu (Reference date: 1 January 1992). Information values for 57 Co, 90 Sr, 106 Ru, 125 Sb, 210 Pb, 210 Po, 228 Th, 230 Th, 234 U, 235 U, 238 U and 241 Am are also reported. All values are expressed in Bq kg -1 dry weight. (author)

  5. Intercomparison of radionuclide measurements in marine sediment sample IAEA-367

    Energy Technology Data Exchange (ETDEWEB)

    Ballestra, S; Lopez, J J; Gastaud, J; Vas, D; Noshkin, V

    1991-08-01

    The results of an intercomparison exercise on a Pacific Ocean sediment sample, IAEA-367, designed for the determination of artificial and natural radionuclides levels, are reported. The data from 81 laboratories representing 37 countries have been evaluated. The following are the recommended values, with confidence intervals, for {sup 60}Co, {sup 90}Sr, {sup 137}Cs, {sup 239+240}Pu (Reference date: 1 January 1990). Information values for {sup 155}Eu, {sup 238}Pu, {sup 241}Am, and {sup 241}Pu are reported. Information values for the following natural radionuclides {sup 40}K, {sup 226}Ra, {sup 228}Th, {sup 230}Th, {sup 234}U, {sup 235}U and {sup 238}U are also reported. (author)

  6. Intercomparison of radionuclide measurements in marine sediment sample IAEA-135

    Energy Technology Data Exchange (ETDEWEB)

    Ballestra, S; Gastaud, J; Lopez, J J; Parsi, P; Vas, D

    1993-08-01

    The results of an intercomparison exercise on a marine sediment from Irish Sea, IAEA-135, designed for the determination of artificial and natural radionuclides levels, are reported. The data from 151 laboratories representing 51 countries have been evaluated. The following are the recommended values, with confidence intervals, for {sup 40}K, {sup 60}Co, {sup 134}Cs, {sup 137}Cs, {sup 154}Eu, {sup 155}Eu, {sup 226}Ra, {sup 228}Ra, {sup 232}Th,{sup 238}Pu, {sup 239+240}Pu (Reference date: 1 January 1992). Information values for {sup 57}Co, {sup 90}Sr, {sup 106}Ru, {sup 125}Sb, {sup 210}Pb, {sup 210}Po, {sup 228}Th, {sup 230}Th, {sup 234}U, {sup 235}U, {sup 238}U and {sup 241}Am are also reported. All values are expressed in Bq kg{sup -1} dry weight. (author)

  7. Intercomparison of radionuclide measurements in marine sediment sample IAEA-368

    Energy Technology Data Exchange (ETDEWEB)

    Ballestra, S; Lopez, J J; Gastaud, J; Parsi, P; Vas, D; Noshkin, V

    1991-08-01

    The results of an intercomparison exercise on a Pacific Ocean sediment sample, IAEA-368, designed for the determination of artificial and natural radionuclides levels, are reported. The data from 89 laboratories representing 37 countries have been evaluated. The following are the recommended values, with confidence intervals, for {sup 60}Co, {sup 155}Eu, {sup 210}7Pb, {sup 226}Ra, {sup 238}U, {sup 238}Pu and{sup 239+240}Pu (Reference date: 1 January 1990). Information values for {sup 40}K, {sup 90}Sr, {sup 137}Cs, {sup 228}Th, {sup 230}Th, {sup 232}Th, {sup 234}U, {sup 235}U and {sup 241}Am are also reported. (author)

  8. Austrian WBC intercomparison by means of a BOMAB phantom

    Energy Technology Data Exchange (ETDEWEB)

    Castellani, C.M.; Battisti, P.; Tarroni [ENEA, Centro Ricerche Ezio Clementel, Bologna (Italy). Dipt. Ambiente; Edelmeier, R. [Bundesamt fuer Eich- und Vermessungswesen, Wien (Austria)

    1998-07-01

    The paper discusses the results obtained in the intercomparison between the Austrian Institute for Legal Metrology and the ENEA (National Agency for New Technology, Energy and the Environment) Institute for Radiation Protection, which gave a BOMAB phantom. Values related to potassium content and MBA (minimum detectable activity) for each identified nuclide are also discussed. [Italian] L'Istituto Austriaco di Metrologia Legale ha organizzato l'interconfronto usando un fantoccio gelificato di tipo BOMAB fornito dall'Istituto di Radioprotezione dell'ENEA nel periodo marzo-giugno 1996. Vengono riportati i risultati ottenuti relativi al contenuto di potassio e all'attivita' minima rilevabile (MDA) per ogni nuclide identificato.

  9. Intercomparison of radionuclide measurements on marine sediment sample IAEA-300

    International Nuclear Information System (INIS)

    Ballestra, S.; Gastaud, J.; Lopez, J.J.; Parsi, P.; Vas, D.

    1994-09-01

    The results of an intercomparison exercise on a sediment from Baltic Sea, IAEA-300, designed for the determination of artificial and natural radionuclides' levels, are reported. The data from 159 laboratories representing 51 countries have been evaluated. The following are the recommended values, with confidence intervals, 40 K, 60 Co, 125 Sb, 134 Cs, 137 Cs, 155 Eu, 210 Pb, 210 Po, 228 Ra, 234 U, 238 U, 239+240 Pu and 241 Am. Information values for 54 Mn, 90 Sr, 226 Ra, 228 Th, 230 Th, 232 Th, 235 U and 238 Pu are also reported. All values are given on the reference date of 1 January 1993 and expressed in Bq kg -1 dry weight. (author)

  10. Report on the intercomparison run IAEA-156 radionuclides in clover

    International Nuclear Information System (INIS)

    Strachnov, V.; Valkovic, V.; Dekner, R.

    1991-01-01

    This report contains the results of the intercomparison IAEA-156 on the determination of radionuclides in clover. Initially participants were requested to determine the levels of 134 Cs, 137 Cs, 40 K, 90 Sr and invited to provide data for other radionuclides. The participants included 46 laboratories located in 25 countries, and statistical evaluation of their data yield recommended values for these four radionuclides. Additional radionuclides reported were 210 Pb, 239 Pu and 125 Sb; however, insufficient data exists to statistically determine recommended values for these radionuclides. The following are the recommended values, with confidence intervals, for the most frequently measured radionuclides (reference date: 1 August 1986): 134 Cs 132.1 Bq/kg (126.4-137.7); 137 Cs 264 Bq/kg (254-274); 40 K 657 Bq/kg (637-676); 90 Sr 14.8 Bq/kg (13.4-16.3). Figs and tabs

  11. Intercomparison test on hearing protectors (EU, VG4)

    DEFF Research Database (Denmark)

    Poulsen, Torben

    1997-01-01

    Real Ear Attenuation at Threshold (REAT) was measured on 16 human test subjects in accordance with EN 24869-1. Insertion loss for the individual cups was determined in accordance with EN 352-1, paragraph 7.11-7.11.3.3. Both the REAT and the insertion loss measurements were performed in an approxi......Real Ear Attenuation at Threshold (REAT) was measured on 16 human test subjects in accordance with EN 24869-1. Insertion loss for the individual cups was determined in accordance with EN 352-1, paragraph 7.11-7.11.3.3. Both the REAT and the insertion loss measurements were performed...... in an approximated diffuse field. The field was established in a semi reverberant room with uncorrelated one-third octave bands of noise from two loudspeakers. The measurements are part of a European intercomparison project 'Sound attenuation in accordance with EN-24869-1'....

  12. Ground-based intercomparison of two isoprene measurement techniques

    Directory of Open Access Journals (Sweden)

    E. Leibrock

    2003-01-01

    Full Text Available An informal intercomparison of two isoprene (C5H8 measurement techniques was carried out during Fall of 1998 at a field site located approximately 3 km west of Boulder, Colorado, USA. A new chemical ionization mass spectrometric technique (CIMS was compared to a well-established gas chromatographic technique (GC. The CIMS technique utilized benzene cation chemistry to ionize isoprene. The isoprene levels measured by the CIMS were often larger than those obtained with the GC. The results indicate that the CIMS technique suffered from an anthropogenic interference associated with air masses from the Denver, CO metropolitan area as well as an additional interference occurring in clean conditions. However, the CIMS technique is also demonstrated to be sensitive and fast. Especially after introduction of a tandem mass spectrometric technique, it is therefore a candidate for isoprene measurements in remote environments near isoprene sources.

  13. SSDL Argentina: Dosimetric intercomparison programme for cobalt 60 therapy units

    Energy Technology Data Exchange (ETDEWEB)

    Saravi, M; Papadopulos, S; Mugliaroli, H [Comision Nacional de Energia Atomica, Buenos Aires (Argentina)

    1996-08-01

    Thermoluminescence dosimeters (TLD) are widely used to verify absorbed dose delivered from radiation therapy beams. The Secondary Standard Dosimetry Laboratory (SSDL) of Argentina uses TLD for its mailed dose intercomparison programme for cobalt 60 radiation therapy units. Results obtained since 1978 as well as causes of dose discrepancies greater than 5% are analyzed. Results of the external quality control performed by the IAEA for this programme indicate that the dose evaluated by the SSDL TLD service for the participating centers is about 1% lower than that evaluated by the IAEA TLD service. This deviation is accepted taking on account that a {+-} 2% dose uncertainty for TLD dosimetry is reasonable. (author). 5 refs, 5 figs, 2 tabs.

  14. Intercomparison of radionuclide measurements on marine sediment sample IAEA-300

    Energy Technology Data Exchange (ETDEWEB)

    Ballestra, S; Gastaud, J; Lopez, J J; Parsi, P; Vas, D

    1994-09-01

    The results of an intercomparison exercise on a sediment from Baltic Sea, IAEA-300, designed for the determination of artificial and natural radionuclides' levels, are reported. The data from 159 laboratories representing 51 countries have been evaluated. The following are the recommended values, with confidence intervals, {sup 40}K, {sup 60}Co, {sup 125}Sb, {sup 134}Cs, {sup 137}Cs, {sup 155}Eu, {sup 210}Pb, {sup 210}Po, {sup 228}Ra, {sup 234}U, {sup 238}U, {sup 239+240}Pu and {sup 241}Am. Information values for {sup 54}Mn, {sup 90}Sr, {sup 226}Ra, {sup 228}Th, {sup 230}Th, {sup 232}Th, {sup 235}U and {sup 238}Pu are also reported. All values are given on the reference date of 1 January 1993 and expressed in Bq kg{sup -1} dry weight. (author)

  15. Calibrating nacelle lidars

    Energy Technology Data Exchange (ETDEWEB)

    Courtney, M.

    2013-01-15

    Nacelle mounted, forward looking wind lidars are beginning to be used to provide reference wind speed measurements for the power performance testing of wind turbines. In such applications, a formal calibration procedure with a corresponding uncertainty assessment will be necessary. This report presents four concepts for performing such a nacelle lidar calibration. Of the four methods, two are found to be immediately relevant and are pursued in some detail. The first of these is a line of sight calibration method in which both lines of sight (for a two beam lidar) are individually calibrated by accurately aligning the beam to pass close to a reference wind speed sensor. A testing procedure is presented, reporting requirements outlined and the uncertainty of the method analysed. It is seen that the main limitation of the line of sight calibration method is the time required to obtain a representative distribution of radial wind speeds. An alternative method is to place the nacelle lidar on the ground and incline the beams upwards to bisect a mast equipped with reference instrumentation at a known height and range. This method will be easier and faster to implement and execute but the beam inclination introduces extra uncertainties. A procedure for conducting such a calibration is presented and initial indications of the uncertainties given. A discussion of the merits and weaknesses of the two methods is given together with some proposals for the next important steps to be taken in this work. (Author)

  16. Bico 2: second national intercomparison campaign of WBC centres working in Italy; Bico 2: la seconda campagna MIDIA di interconfronto dei WBC operanti in Italia

    Energy Technology Data Exchange (ETDEWEB)

    Castellani, C.M.; Battisti, P.; Tarroni, G. [ENEA, Centro Ricerche `Ezio Clementel`, Bologna (Italy). Dip. Ambiente

    1998-12-31

    During the period November 1994 - May 1995 the coordinating group of WBC centres working in Italy organised the 2. national intercalibration and intercomparison campaign. A BOMAB phantom was used filled with four radionuclides gel solution with gamma energy emissions ranging between 100 keV and 2 MeV. 17 out of 21 Italian WBC centres took part in the campaign. Through the intercalibration, organised according to internationally accepted methodologies, each WBC centre could check its own calibration procedures. many intermediate data, collected for the methodologies and measurement procedures intercomparison, permitted analyses and comparison of uncertainly causes in a WBC measurement of the internal contamination. A proposal of MDA definition and assessment procedure resulted from the intercomparison campaign. [Italiano] Il Coordinamento dei Centri WBC operanti in Italia ha organizzato la seconda campagna di intercalibrazione ed interconfronto nazionale basata sulle misure di un fantoccio BOMAB riempito con una soluzione radioattiva gelificata contenente 4 radionuclidi con emissioni gamma nell`intervallo energetico compreso fra 100 keV e 2 MeV. Alla campagna, che si e` svolta fra novembre 1994 e maggio 1995, hanno partecipato 17 dei 21 Centri WBC censiti in Italia. L`intercalibrazione e` stata organizzata secondo criteri ormai consolidati in campo internazionale ed ha permesso ad ognuno dei partecipanti di verificare le proprie procedure di calibrazione. Per l`interconfronto delle procedure e dei metodi di misura impiegati e` stata raccolta una serie di dati intermedi che hanno consentito di analizzare e confrontare le fonti di incertezza insite nella misura di contaminazione interna nell`uomo tramite WBC. Cio` ha infine reso possibile una proposta di definizione e di procedura di determinazione del valore della minima attivita` rivelabile (MDA) in accordo con le piu` recenti tendenze in campo internazionale.

  17. Intercomparison of ozone measurements between Lidar and ECC-sondes

    Energy Technology Data Exchange (ETDEWEB)

    Grabbe, G.C. [Max-Planck-Institut fuer Meteorologie, Hamburg (Germany); Boesenberg, J. [Max-Planck-Institut fuer Meteorologie, Hamburg (Germany); Dier, H. [Meteorologisches Obs., Lindenberg (Germany); Goersdorf, U. [Meteorologisches Obs., Lindenberg (Germany); Matthias, V. [Max-Planck-Institut fuer Meteorologie, Hamburg (Germany); Peters, G. [Meteorologisches Obs., Lindenberg (Germany); Schaberl, T. [Hamburg Univ. (Germany). Meteorologisches Inst.; Senff, C. [Hamburg Univ. (Germany). Meteorologisches Inst.

    1996-02-01

    An intercomparison experiment for measurements of ozone vertical profiles in the lower troposphere was performed using a ground-based ozone DIAL (DIfferential Absorption Lidar) and ECC-sondes (Electrochemical Concentration Cell) attached to tethered as well as free flying balloons, which took place in June of 1994. The tethered balloon was used for ozone soundings in the planetary boundary layer up to an altitude of 500 m, while in the free troposphere free flying balloons were used. For the time series of up to 90 min obtained with the tethersondes both averages and standard deviations are compared. The mean difference for all measurements amounted to 3.5 {mu}g/m{sup 3} only, corresponding to 3.5%. For the instantaneous profiles compared to the free flying sondes the differences were only marginally larger, with a mean value of 3.6 {mu}g/m{sup 3} corresponding to 4.1%. With two exceptions all averages for a single profile stayed below 7 {mu}g/m{sup 3}. Larger individual excursions were observed. In some cases, in particular in regions of steep aerosol gradients at layer boundaries, most probably the lidar values cause the deviation, while in other cases the ECC-sonde is suspected to yield erroneous results. For the measured standard deviation those retrieved from DIAL measurements are generally larger than measured by the ECC-sondes, especially in regions of inhomogeneous aerosol distribution. For the measurements reported here, this is attributed to residual errors in the aerosol correction of the DIAL measurements. The general agreement found in this intercomparison is regarded as excellent, DIAL is proven to be a very valuable tool for detailed studies of the ozone distribution in the lower troposphere. (orig.)

  18. The third RAdiation transfer Model Intercomparison (RAMI) exercise: Documenting progress in canopy reflectance models

    NARCIS (Netherlands)

    Widlowski, J.L.; Taberner, M.; Pinty, B.; Bruniquel-Pinel, V.; Disney, M.I.; 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.; Thompson, R.; Verhoef, W.; Verstraete, M.M.; Xie, D.

    2007-01-01

    [1] 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

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

    NARCIS (Netherlands)

    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.; Mottus, M.; North, P.R.J.; Qin, W.; Robustelli, M.; Rochdi, N.; Ruiloba, R.; Soler, C.; Thompson, R.; Verhoef, W.; Xie, D.; Thompson, R.

    2007-01-01

    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

  20. Report on the intercomparison run IAEA-384. Radionuclides in Fangataufa lagoon sediment

    International Nuclear Information System (INIS)

    Povinec, P.P.; Pham, M.K.

    2000-01-01

    The accurate and precise determinations of radionuclide concentrations in marine samples are important aspects of marine radioactivity assessments and the use of radionuclides in studies of oceanographic processes. To address the problem of data quality, and to assist Member States in verifying the performance of their laboratories, the IAEA Marine Environment Laboratory (MEL) in Monaco has conducted intercomparison exercises on radionuclides in marine samples for many years as part of its contribution to the IAEA's programme of Analytical Quality Control Services (AQCS). For this intercomparison exercise, in 1996 IAEA-MEL collected sediment in Fangataufa lagoon, French Polynesia. The sample aliquots were distributed during 1997-1998 for intercomparison of anthropogenic and natural radionuclides. 110 laboratories worldwide agreed to participate. Of these, only 94 sent results which could be used in the evaluation of this intercomparison exercise. This report describes the results obtained from 94 laboratories on anthropogenic and natural radionuclide determinations in Fangataufa lagoon sediment

  1. Report on the intercomparison run IAEA-384. Radionuclides in Fangataufa lagoon sediment

    Energy Technology Data Exchange (ETDEWEB)

    Povinec, P P; Pham, M K

    2000-07-01

    The accurate and precise determinations of radionuclide concentrations in marine samples are important aspects of marine radioactivity assessments and the use of radionuclides in studies of oceanographic processes. To address the problem of data quality, and to assist Member States in verifying the performance of their laboratories, the IAEA Marine Environment Laboratory (MEL) in Monaco has conducted intercomparison exercises on radionuclides in marine samples for many years as part of its contribution to the IAEA's programme of Analytical Quality Control Services (AQCS). For this intercomparison exercise, in 1996 IAEA-MEL collected sediment in Fangataufa lagoon, French Polynesia. The sample aliquots were distributed during 1997-1998 for intercomparison of anthropogenic and natural radionuclides. 110 laboratories worldwide agreed to participate. Of these, only 94 sent results which could be used in the evaluation of this intercomparison exercise. This report describes the results obtained from 94 laboratories on anthropogenic and natural radionuclide determinations in Fangataufa lagoon sediment.

  2. IAEA intercomparisons in the frame of the occupational radiation protection programme

    International Nuclear Information System (INIS)

    Mrabit, K.; Cruz Suarez, R.

    2005-01-01

    The IAEA safety activities to support the assessment of occupational exposure through a comprehensive set of safety guides, safety reports and other related documents will soon be completed. Several intercomparison exercises were organized by the IAEA on the determination of radionuclides in human urine samples, whole body counting and external dosimetry. These previous intercomparison exercises revealed significant differences in the approaches, methods and assumptions, and consequently in the results. This underlined the importance of this kind of intercomparison programme as a key element of the international harmonization of quantities and units. The purpose of this paper is to present the current and future IAEA activities in support of assessment of occupational exposure by organizing intercomparison runs

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

    International Nuclear Information System (INIS)

    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

  4. Results and recommendations from an intercomparison of six Hygroscopicity-TDMA systems

    Directory of Open Access Journals (Sweden)

    A. Massling

    2011-03-01

    Full Text Available The performance of six custom-built Hygrocopicity-Tandem Differential Mobility Analyser (H-TDMA systems was investigated in the frame of an international calibration and intercomparison workshop held in Leipzig, February 2006. The goal of the workshop was to harmonise H-TDMA measurements and develop recommendations for atmospheric measurements and their data evaluation. The H-TDMA systems were compared in terms of the sizing of dry particles, relative humidity (RH uncertainty, and consistency in determination of number fractions of different hygroscopic particle groups. The experiments were performed in an air-conditioned laboratory using ammonium sulphate particles or an external mixture of ammonium sulphate and soot particles.

    The sizing of dry particles of the six H-TDMA systems was within 0.2 to 4.2% of the selected particle diameter depending on investigated size and individual system. Measurements of ammonium sulphate aerosol found deviations equivalent to 4.5% RH from the set point of 90% RH compared to results from previous experiments in the literature. Evaluation of the number fraction of particles within the clearly separated growth factor modes of a laboratory generated externally mixed aerosol was done. The data from the H-TDMAs was analysed with a single fitting routine to investigate differences caused by the different data evaluation procedures used for each H-TDMA. The differences between the H-TDMAs were reduced from +12/−13% to +8/−6% when the same analysis routine was applied. We conclude that a common data evaluation procedure to determine number fractions of externally mixed aerosols will improve the comparability of H-TDMA measurements.

    It is recommended to ensure proper calibration of all flow, temperature and RH sensors in the systems. It is most important to thermally insulate the aerosol humidification unit and the second DMA and to monitor these temperatures to an accuracy of 0.2 °C. For the

  5. Traceable calibration of hospital 192Ir HDR sources

    International Nuclear Information System (INIS)

    Govinda Rajan, K.N.; Bhatt, B.C.; Pendse, A.M.; Kannan, V.

    2002-01-01

    Presently, no primary standard exists for the standardization of remote afterloading 192 Ir HDR sources. These sources are, therefore, being standardized by a few Secondary Standard Dosimetry Laboratories (SSDLs), in terms of Air Kerma Strength (AKS) or Reference Air Kerma Rate (RAKR) using a 0.6 cc Farmer type chamber, set up as an Interim Standard. These SSDLs offer calibration to well type of ionization chambers that are normally used by the hospitals for calibrating the 192 lr HDR source. Presently, in many countries, including India, well chambers are not commercially available. Nor do these countries offer any calibration service for 192 lr HDR source. With the result users make use of well chambers imported from different countries with their calibration traceable to the country of origin. Since no intercomparisons between these countries have been reported, the measurement consistency between hospitals becomes questionable. The problem is compounded by the fact that these chambers are used for several years without re-calibration since no calibration service is locally available. For instance, in India, the chambers have been in use in hospitals, since 1994, without a second calibration. Not all hospitals use the well chamber for the calibration of the 192 lr HDR source. Many hospitals make use of 0.6 cc chambers, in air, at short source to chamber distances, for measuring the AKS of the source. The latter method is prone to much larger inaccuracy due to the use of very short source to chamber distances without proper calibration jigs, use of 60 Co calibration factor for 192 Ir HDR source calibrations, neglecting correction factors for room scatter, fluence non-uniformity, use of arbitrary buildup factors for the buildup cap of the chamber etc. A comparison of the procedures used at hospitals revealed that various arbitrary methods are in use at hospitals. An indigenously developed well chamber was calibrated against a Reference Standard traceable to the

  6. HPLC/DAD Intercomparison on Phytoplankton Pigments (HIP-1, HIP-2, HIP-3 and HIP-4)

    OpenAIRE

    CANUTI Elisabetta; RAS Josephine; GRUNG Merete; ROTTGERS Rudiger; COSTA GOELA Priscilla; ARTUSO Florinda; CATALDI Dario

    2016-01-01

    From 2009 to 2015, in the context of the MERIS (Medium Resolution Imaging Spectrometer) validation activities, the JRC Marine Optical Laboratory organised four HPLC Intercomparison exercises for Phytoplankton Pigment measurements (HIP-1, HIP-2, HIP-3 and HIP-4), involving seven European accredited and reference laboratories. The objectives of these intercomparison exercises were: creating a reference community at European level for phytoplankton pigment analysis capable of supporting satel...

  7. Intercomparison run for uranium and tritium determination in urine samples, organised by Nuclear Regulatory Authority, Argentina

    CERN Document Server

    Serdeiro, N H; Equillor, H E

    2003-01-01

    The Nuclear Regulatory Authority (ARN), Argentina, has carried out an intercomparison run for tritium and uranium determination in urine, in November 2002. The aim of this exercise was to assess the performance of the laboratories that usually inform these radionuclides and to provide technical support in order to have an appropriate occupational monitoring in vitro. In the present work, the results of the intercomparison and the assessment of each laboratory are published.

  8. Intercomparison run for uranium and tritium determination in urine samples, organised by Nuclear Regulatory Authority, Argentina

    International Nuclear Information System (INIS)

    Serdeiro, Nelida H.; Equillor, Hugo E.; Bonino, Nestor O.

    2003-01-01

    The Nuclear Regulatory Authority (ARN), Argentina, has carried out an intercomparison run for tritium and uranium determination in urine, in November 2002. The aim of this exercise was to assess the performance of the laboratories that usually inform these radionuclides and to provide technical support in order to have an appropriate occupational monitoring in vitro. In the present work, the results of the intercomparison and the assessment of each laboratory are published. (author)

  9. ACTRIS non-methane hydrocarbon intercomparison experiment in Europe to support WMO GAW and EMEP observation networks

    Science.gov (United States)

    Hoerger, C. C.; Claude, A.; Plass-Duelmer, C.; Reimann, S.; Eckart, E.; Steinbrecher, R.; Aalto, J.; Arduini, J.; Bonnaire, N.; Cape, J. N.; Colomb, A.; Connolly, R.; Diskova, J.; Dumitrean, P.; Ehlers, C.; Gros, V.; Hakola, H.; Hill, M.; Hopkins, J. R.; Jäger, J.; Junek, R.; Kajos, M. K.; Klemp, D.; Leuchner, M.; Lewis, A. C.; Locoge, N.; Maione, M.; Martin, D.; Michl, K.; Nemitz, E.; O'Doherty, S.; Pérez Ballesta, P.; Ruuskanen, T. M.; Sauvage, S.; Schmidbauer, N.; Spain, T. G.; Straube, E.; Vana, M.; Vollmer, M. K.; Wegener, R.; Wenger, A.

    2015-07-01

    The performance of 18 European institutions involved in long-term non-methane hydrocarbon (NMHC) measurements in ambient air within the framework of the Global Atmosphere Watch (GAW) and the European Monitoring and Evaluation Programme (EMEP) was assessed with respect to data quality objectives (DQOs) of ACTRIS (Aerosols, Clouds, and Trace gases Research InfraStructure Network) and GAW. Compared to previous intercomparison studies the DQOs define a novel approach to assess and ensure a high quality of the measurements. Having already been adopted by GAW, the ACTRIS DQOs are demanding with deviations to a reference value of less than 5 % and a repeatability of better than 2 % for NMHC mole fractions above 0.1 nmol mol-1. The participants of the intercomparison analysed two dry gas mixtures in pressurised cylinders, a 30-component NMHC mixture in nitrogen (NMHC_N2) at approximately 1 nmol mol-1 and a whole air sample (NMHC_air), following a standardised operation procedure including zero- and calibration gas measurements. Furthermore, participants had to report details on their instruments and assess their measurement uncertainties. The NMHCs were analysed either by gas chromatography-flame ionisation detection (GC-FID) or by gas chromatography-mass spectrometry (GC-MS). For the NMHC_N2 measurements, 62 % of the reported values were within the 5 % deviation class corresponding to the ACTRIS DQOs. For NMHC_air, generally more frequent and larger deviations to the assigned values were observed, with 50 % of the reported values within the 5 % deviation class. Important contributors to the poorer performance in NMHC_air compared to NMHC_N2 were a more complex matrix and a larger span of NMHC mole fractions (0.03-2.5 nmol mol-1). The performance of the participating laboratories were affected by the different measurement procedures such as the usage of a two-step vs. a one-step calibration, breakthroughs of C2-C3 hydrocarbons in the focussing trap, blank values in zero

  10. Assessing the impact of land use change on hydrology by ensemble modeling (LUCHEM). I: Model intercomparison with current land use

    Science.gov (United States)

    Breuer, L.; Huisman, J.A.; Willems, P.; Bormann, H.; Bronstert, A.; Croke, B.F.W.; Frede, H.-G.; Graff, T.; Hubrechts, L.; Jakeman, A.J.; Kite, G.; Lanini, J.; Leavesley, G.; Lettenmaier, D.P.; Lindstrom, G.; Seibert, J.; Sivapalan, M.; Viney, N.R.

    2009-01-01

    This paper introduces the project on 'Assessing the impact of land use change on hydrology by ensemble modeling (LUCHEM)' that aims at investigating the envelope of predictions on changes in hydrological fluxes due to land use change. As part of a series of four papers, this paper outlines the motivation and setup of LUCHEM, and presents a model intercomparison for the present-day simulation results. Such an intercomparison provides a valuable basis to investigate the effects of different model structures on model predictions and paves the ground for the analysis of the performance of multi-model ensembles and the reliability of the scenario predictions in companion papers. In this study, we applied a set of 10 lumped, semi-lumped and fully distributed hydrological models that have been previously used in land use change studies to the low mountainous Dill catchment, Germany. Substantial differences in model performance were observed with Nash-Sutcliffe efficiencies ranging from 0.53 to 0.92. Differences in model performance were attributed to (1) model input data, (2) model calibration and (3) the physical basis of the models. The models were applied with two sets of input data: an original and a homogenized data set. This homogenization of precipitation, temperature and leaf area index was performed to reduce the variation between the models. Homogenization improved the comparability of model simulations and resulted in a reduced average bias, although some variation in model data input remained. The effect of the physical differences between models on the long-term water balance was mainly attributed to differences in how models represent evapotranspiration. Semi-lumped and lumped conceptual models slightly outperformed the fully distributed and physically based models. This was attributed to the automatic model calibration typically used for this type of models. Overall, however, we conclude that there was no superior model if several measures of model

  11. Vibration transducer calibration techniques

    Science.gov (United States)

    Brinkley, D. J.

    1980-09-01

    Techniques for the calibration of vibration transducers used in the Aeronautical Quality Assurance Directorate of the British Ministry of Defence are presented. Following a review of the types of measurements necessary in the calibration of vibration transducers, the performance requirements of vibration transducers, which can be used to measure acceleration, velocity or vibration amplitude, are discussed, with particular attention given to the piezoelectric accelerometer. Techniques for the accurate measurement of sinusoidal vibration amplitude in reference-grade transducers are then considered, including the use of a position sensitive photocell and the use of a Michelson laser interferometer. Means of comparing the output of working-grade accelerometers with that of previously calibrated reference-grade devices are then outlined, with attention given to a method employing a capacitance bridge technique and a method to be used at temperatures between -50 and 200 C. Automatic calibration procedures developed to speed up the calibration process are outlined, and future possible extensions of system software are indicated.

  12. Calibration Under Uncertainty.

    Energy Technology Data Exchange (ETDEWEB)

    Swiler, Laura Painton; Trucano, Timothy Guy

    2005-03-01

    This report is a white paper summarizing the literature and different approaches to the problem of calibrating computer model parameters in the face of model uncertainty. Model calibration is often formulated as finding the parameters that minimize the squared difference between the model-computed data (the predicted data) and the actual experimental data. This approach does not allow for explicit treatment of uncertainty or error in the model itself: the model is considered the %22true%22 deterministic representation of reality. While this approach does have utility, it is far from an accurate mathematical treatment of the true model calibration problem in which both the computed data and experimental data have error bars. This year, we examined methods to perform calibration accounting for the error in both the computer model and the data, as well as improving our understanding of its meaning for model predictability. We call this approach Calibration under Uncertainty (CUU). This talk presents our current thinking on CUU. We outline some current approaches in the literature, and discuss the Bayesian approach to CUU in detail.

  13. Intercomparisons for integrating the radon-thoron detector of NIRP, China with NIRS, Japan

    International Nuclear Information System (INIS)

    Wu, Yunyun; Cui, Hongxing; Zhang, Qingzhao; Shang, Bing

    2015-01-01

    Intercomparisons play an important role in maintaining a reasonable and accurate standard of measurement and quality. Integrating the radon-thoron detector of the National Institute for Radiological Protection (NIRP), China has continuously been a subject of four rounds of international intercomparisons organised by the National Institute of Radiological Sciences (NIRS), Japan during 2007-12. The intercomparisons were held at NIRS. The exercises included different exposures for both radon and thoron. The results of the intercomparison for the detectors of NIRP for both radon and thoron exposures were in the range of ±20 % from the reference value and were categorised as 'Category I' in the intercomparison carried out in 2011. The radon and thoron results of the LD-P detector in four rounds of intercomparison exercises were summarised, and uncertainties of all the radon and thoron results of NIRP were within the acceptable range of 30 % in environment. Radon and thoron measurement results between NIRP and NIRS were basically in agreement. (authors)

  14. The role of intercomparisons and intercalibrations in the improvement of internal dose assessment

    International Nuclear Information System (INIS)

    Griffith, R.V.

    2000-01-01

    In vivo monitoring and dose assessment is a highly technical field. Moreover, it is carried out by a relatively small number of specialists. A number of technical steps can be taken to improve internal dosimetry programmes. However, one of the most valuable activities for overall improvement of measurement programmes is active participation in national and international intercomparisons and intercalibrations. These bring a number of benefits to the internal dosimetry programme, including validation of measurement practices, harmonisation of techniques, information exchange, and training. The number of intercalibration and intercomparison activities conducted on the national and international level has grown in recent years. These activities may involve actual measurement programmes or calculation exercises to compare approaches used for assessment of internal dose from measurement results. When conducted effectively such programmes are a highly cost effective use of limited resources. They also contribute to the credibility of the overall dosimetry process. Intercomparisons should be an important component of the in vivo measurement programme. Cooperation between the organisers of various intercomparison activities is essential to avoid unnecessary duplication and ensure the most effective use of the participants' time and energy. Future activities should address the use of simplified phantoms and source arrays to expedite shipping, reduce cost, and contribute to more timely conduct of intercomparisons. It is also important that managers and regulatory authorities be prepared to support intercomparison and intercalibration programmes. (author)

  15. Intercomparison of reactive transport models applied to degradation of a concrete / clay interface

    International Nuclear Information System (INIS)

    Burnol, A.; Blanc, P.; Tournassat, C.; Lassin, A.; Gaucher, E.C.

    2005-01-01

    Full text of publication follows: Assuming a future disposal of spent nuclear fuel in deep geologic formation of Callovian- Oxfordian argillite in France, concrete will be used extensively to construct the disposal chambers in the host formation, and also as radioactive waste containment material. After being sealed, the repository will become saturated with interstitial waters from the Callovian-Oxfordian argillite, which will produce high pH solutions through interaction with the concrete. The aggressiveness of these alkaline solutions may weaken the clay's confinement properties (bentonite and argillite) with respect to long-lived radionuclides by change of the mineralogy. Conversely, the clayey formation with a high partial pressure of CO 2 represents an aggressive media for the concrete. The hydrogeological and chemical reactions of deep-underground systems are therefore intimately coupled and reactive transport models are increasingly used for performance assessment of nuclear waste disposal [1]. The main objective of this study is to present an intercomparison study using different reactive transport codes, where among PHREEQC1D [2], PHAST [3] and TOUGHREACT [4] applied to determine, in space and time, the extension of the alkaline perturbation and the associated degradation of concrete. The calculations were carried out after the definition of a complete mineralogy for both media. The experimental work made in the European Ecoclay II project [5] allowed a selection of reaction paths and of new phases for the thermodynamic database. Calculations were carried out over a simulated period of 100,000 years at different temperatures. Results of the different codes are compared and discussed. [1] De Windt L., Burnol A., Montarnal P., Van Der Lee.J., (2003) Intercomparison of reactive transport models applied to UO 2 oxidative dissolution and uranium migration., Journal of Contaminant Hydrology, 61, 1-4, 303-312; [2] Parkhurst D.L., Appelo C.A.J. (1999) - User

  16. Climatic calibration of pollen data: a user's guide for the applicable computer programs in the Statistical Package for Social Scientists (SPSS)

    Energy Technology Data Exchange (ETDEWEB)

    Arigo, R.; Howe, S.E.; Webb, T. III

    1984-06-01

    Radiocarbon-dated pollen records are a source of quantitative estimates for climatic variables for the past 9000 years. Multiple regression is the main method for calculation of these estimates and requires a series of steps to gain equations that meet the statistical assumptions of the analysis. This manual describes these steps which include (1) selection of the region for analysis, (2) selection of the pollen types for statiscal analysis, (3) deletion of univariate outliers, (4) transformation to produce linear relationships, (5) selection of the regression equation, and (6) tests of the regression residuals. The input commands and the output from a series of SPSS (Statistical Package for Social Scientists) programs are illustrated and described, and, as an example, modern pollen and climatic data from lower Michigan are used to calculate a regression equation for July mean temperature. 19 references, 1 table.

  17. Ibis ground calibration

    International Nuclear Information System (INIS)

    Bird, A.J.; Barlow, E.J.; Tikkanen, T.; Bazzano, A.; Del Santo, M.; Ubertini, P.; Blondel, C.; Laurent, P.; Lebrun, F.; Di Cocco, G.; Malaguti, E.; Gabriele, M.; La Rosa, G.; Segreto, A.; Quadrini, E.; Volkmer, R.

    2003-01-01

    We present an overview of results obtained from IBIS ground calibrations. The spectral and spatial characteristics of the detector planes and surrounding passive materials have been determined through a series of calibration campaigns. Measurements of pixel gain, energy resolution, detection uniformity, efficiency and imaging capability are presented. The key results obtained from the ground calibration have been: - optimization of the instrument tunable parameters, - determination of energy linearity for all detection modes, - determination of energy resolution as a function of energy through the range 20 keV - 3 MeV, - demonstration of imaging capability in each mode, - measurement of intrinsic detector non-uniformity and understanding of the effects of passive materials surrounding the detector plane, and - discovery (and closure) of various leakage paths through the passive shielding system

  18. Gamma counter calibration system

    International Nuclear Information System (INIS)

    1977-01-01

    A method and apparatus are described for the calibration of a gamma radiation measurement instrument to be used over any of a number of different absolute energy ranges. The method includes the steps of adjusting the overall signal gain associated with pulses which are derived from detected gamma rays, until the instrument is calibrated for a particular absolute energy range; then storing parameter settings corresponding to the adjusted overall signal gain, and repeating the process for other desired absolute energy ranges. The stored settings can be subsequently retrieved and reapplied so that test measurements can be made using a selected one of the absolute energy ranges. Means are provided for adjusting the overall signal gain and a specific technique is disclosed for making coarse, then fine adjustments to the signal gain, for rapid convergence of the required calibration settings. (C.F.)

  19. Results of the First Evaluation Exercise of the Traceability of Isotope Calibrators in Nuclear Medicine Services of the Community of Madrid

    International Nuclear Information System (INIS)

    Garcia-Torano Martinez, E.; Los Arcos Mrenio, J. M.; Roteta Ibarra, M.

    2002-02-01

    To evaluate the traceability of isotope calibrators in the Community of Madrid, an intercomparison exercise was organised by the Laboratorio de Metrologia de Radiaciones Ionizantes (CIEMAT). Samples of ''1 31 I and ''9 9m Tc were submitted to the participant laboratories for measurement. Values reported by the participants and reference values are discussed and compared in tables and graphs and some recommendations are made. (Author) 3 refs

  20. An initial limited biodosimetry inter-comparison exercise: FOI and DRDC Ottawa

    International Nuclear Information System (INIS)

    Stricklin, D.; Wilkinson, D.; Arvidsson, E.; Prud'homme-Lalonde, L.; Thorleifson, E.; Mullins, D.; Lachapelle, S.

    2007-01-01

    While biodosimetry is a valuable tool in radiation dose assessment, the dicentric assay, which is the most validated method to date, requires some degree of technical competence. Recently published ISO guidelines indicate the need for documenting competence and establishment of quality control programs. Inter-laboratory comparisons are required to document the ability to perform reproducible and accurate assessments. FOI and DRDC Ottawa have conducted an initial limited biodosimetry exercise inter-comparison for quality assurance purposes. The exercise involved blinded exchange of three previously prepared slides from each laboratory from samples that had been evaluated for each lab's dose-response curve. Approximately 100 cells from each slide were evaluated and aberration frequencies reported and compared to the expected frequencies. The limited number of cells evaluated for each sample could not permit statistically distinguishing a 20% difference in all the samples. However, the results indicated reasonable agreement in analyses for all samples for triage purposes. Comparison of aberration frequencies, rather than dose estimates, further illustrates consistent scoring criteria between the two laboratories. The exercise conducted by FOI and DRDC Ottawa provided an efficient means of documenting expertise. Such cooperation further establishes the international biodosimetry network and ensures our readiness for emergency response

  1. Individual dosimetry and calibration

    International Nuclear Information System (INIS)

    Hoefert, M.; Nielsen, M.

    1996-01-01

    In 1995 both the Individual Dosimetry and Calibration Sections worked under the condition of a status quo and concentrated fully on the routine part of their work. Nevertheless, the machine for printing the bar code which will be glued onto the film holder and hence identify the people when entering into high radiation areas was put into operation and most of the holders were equipped with the new identification. As far as the Calibration Section is concerned the project of the new source control system that is realized by the Technical Support Section was somewhat accelerated

  2. Radiation Calibration Measurements

    International Nuclear Information System (INIS)

    Omondi, C.

    2017-01-01

    KEBS Radiation Dosimetry mandate are: Custodian of Kenya Standards on Ionizing radiation, Ensure traceability to International System (SI ) and Calibration radiation equipment. RAF 8/040 on Radioisotope applications for troubleshooting and optimizing industrial process established Radiotracer Laboratory objective is to introduce and implement radiotracer technique for problem solving of industrial challenges. Gamma ray scanning technique applied is to Locate blockages, Locate liquid in vapor lines, Locate areas of lost refractory or lining in a pipe and Measure flowing densities. Equipment used for diagnostic and radiation protection must be calibrated to ensure Accuracy and Traceability

  3. Calibrating Legal Judgments

    Directory of Open Access Journals (Sweden)

    Frederick Schauer

    2017-09-01

    Full Text Available Objective to study the notion and essence of legal judgments calibration the possibilities of using it in the lawenforcement activity to explore the expenses and advantages of using it. Methods dialectic approach to the cognition of social phenomena which enables to analyze them in historical development and functioning in the context of the integrity of objective and subjective factors it determined the choice of the following research methods formallegal comparative legal sociological methods of cognitive psychology and philosophy. Results In ordinary life people who assess other peoplersaquos judgments typically take into account the other judgments of those they are assessing in order to calibrate the judgment presently being assessed. The restaurant and hotel rating website TripAdvisor is exemplary because it facilitates calibration by providing access to a raterrsaquos previous ratings. Such information allows a user to see whether a particular rating comes from a rater who is enthusiastic about every place she patronizes or instead from someone who is incessantly hard to please. And even when less systematized as in assessing a letter of recommendation or college transcript calibration by recourse to the decisional history of those whose judgments are being assessed is ubiquitous. Yet despite the ubiquity and utility of such calibration the legal system seems perversely to reject it. Appellate courts do not openly adjust their standard of review based on the previous judgments of the judge whose decision they are reviewing nor do judges in reviewing legislative or administrative decisions magistrates in evaluating search warrant representations or jurors in assessing witness perception. In most legal domains calibration by reference to the prior decisions of the reviewee is invisible either because it does not exist or because reviewing bodies are unwilling to admit using what they in fact know and employ. Scientific novelty for the first

  4. Calibration of scanning Lidar

    DEFF Research Database (Denmark)

    Gómez Arranz, Paula; Courtney, Michael

    This report describes the tests carried out on a scanning lidar at the DTU Test Station for large wind turbines, Høvsøre. The tests were divided in two parts. In the first part, the purpose was to obtain wind speed calibrations at two heights against two cup anemometers mounted on a mast. Additio......This report describes the tests carried out on a scanning lidar at the DTU Test Station for large wind turbines, Høvsøre. The tests were divided in two parts. In the first part, the purpose was to obtain wind speed calibrations at two heights against two cup anemometers mounted on a mast...

  5. On-line calibration of process instrumentation channels in nuclear power plants

    Energy Technology Data Exchange (ETDEWEB)

    Hashemian, H.M.; Farmer, J.P. [Analysis and Measurement Services Corp., Knoxville, TN (United States)

    1995-04-01

    An on-line instrumentation monitoring system was developed and validated for use in nuclear power plants. This system continuously monitors the calibration status of instrument channels and determines whether or not they require manual calibrations. This is accomplished by comparing the output of each instrument channel to an estimate of the process it is monitoring. If the deviation of the instrument channel from the process estimate is greater than an allowable limit, then the instrument is said to be {open_quotes}out of calibration{close_quotes} and manual adjustments are made to correct the calibration. The success of the on-line monitoring system depends on the accuracy of the process estimation. The system described in this paper incorporates both simple intercomparison techniques as well as analytical approaches in the form of data-driven empirical modeling to estimate the process. On-line testing of the calibration of process instrumentation channels will reduce the number of manual calibrations currently performed, thereby reducing both costs to utilities and radiation exposure to plant personnel.

  6. 40 CFR 92.122 - Smoke meter calibration.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 20 2010-07-01 2010-07-01 false Smoke meter calibration. 92.122 Section 92.122 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS... meter calibration. The smokemeter shall be checked according to the following procedure prior to each...

  7. LLNL X-ray Calibration and Standards Laboratory

    International Nuclear Information System (INIS)

    Anon.

    1982-01-01

    The LLNL X-ray Calibration and Standards Laboratory is a unique facility for developing and calibrating x-ray sources, detectors, and materials, and for conducting x-ray physics research in support of our weapon and fusion-energy programs

  8. AMBER and Ecolego Intercomparisons using Calculations from SR 97

    International Nuclear Information System (INIS)

    Maul, Philip; Robinson, Peter; Avila, Rodolfo; Broed, Robert; Pereira, Antonio

    2003-08-01

    The AMBER compartmental modelling software has been used by Quintessa in undertaking Performance Assessment (PA) calculations for SKI for the last four years. In particular, it was used in helping to identify key issues in the safety case for SFR 1. SSI and the Norwegian Radiation Protection Authority (NRPA) are supporting the development of Ecolego which is based on the Matlab/Simulink general purpose modelling software and provides a user-friendly Graphical User Interface which is particularly suitable for undertaking PA calculations. At SKI/SSI expert group meetings in September 2002, Quintessa presented some radionuclide transport calculations for a deep repository for spent fuel using AMBER. Comparisons were presented with calculations undertaken by SKB in their SR 97 study. It was agreed that it would be useful to undertake some intercomparison calculations using AMBER and Ecolego based on calculation cases considered in SR 97. The reasons for undertaking such intercomparisons include: 1. to give confidence in the use of AMBER and Ecolego for whole system PA calculations for a deep repository; and 2. to provide SKI and SSI with an understanding of some of the technical issues raised by seeking to repeat the SR 97 calculations with different models and software. This report documents the intercomparison calculations that have been undertaken. The main conclusions that have been drawn are: 1. Both modelling packages could successfully reproduce SKB's SR 97 calculations for the near field, geosphere and biosphere. 2. The results of the deterministic calculations for the near field and both deterministic and probabilistic calculations for the biosphere, where AMBER and Ecolego used compartment models, were typically in agreement to within one significant figure. The identical results for the calculated equilibrium inventories in Bay sediments illustrate that the calculations by AMBER and Ecolego are essentially the same when the compartment models are identical

  9. Calibration parameters used to simulate streamflow from application of the Hydrologic Simulation Program-FORTRAN Model (HSPF) to mountainous basins containing coal mines in West Virginia

    Science.gov (United States)

    Atkins, John T.; Wiley, Jeffrey B.; Paybins, Katherine S.

    2005-01-01

    This report presents the Hydrologic Simulation Program-FORTRAN Model (HSPF) parameters for eight basins in the coal-mining region of West Virginia. The magnitude and characteristics of model parameters from this study will assist users of HSPF in simulating streamflow at other basins in the coal-mining region of West Virginia. The parameter for nominal capacity of the upper-zone storage, UZSN, increased from south to north. The increase in UZSN with the increase in basin latitude could be due to decreasing slopes, decreasing rockiness of the soils, and increasing soil depths from south to north. A special action was given to the parameter for fraction of ground-water inflow that flows to inactive ground water, DEEPFR. The basis for this special action was related to the seasonal movement of the water table and transpiration from trees. The models were most sensitive to DEEPFR and the parameter for interception storage capacity, CEPSC. The models were also fairly sensitive to the parameter for an index representing the infiltration capacity of the soil, INFILT; the parameter for indicating the behavior of the ground-water recession flow, KVARY; the parameter for the basic ground-water recession rate, AGWRC; the parameter for nominal capacity of the upper zone storage, UZSN; the parameter for the interflow inflow, INTFW; the parameter for the interflow recession constant, IRC; and the parameter for lower zone evapotranspiration, LZETP.

  10. The ASSET intercomparison of stratosphere and lower mesosphere humidity analyses

    Directory of Open Access Journals (Sweden)

    H. E. Thornton

    2009-02-01

    Full Text Available This paper presents results from the first detailed intercomparison of stratosphere-lower mesosphere water vapour analyses; it builds on earlier results from the EU funded framework V "Assimilation of ENVISAT Data" (ASSET project. Stratospheric water vapour plays an important role in many key atmospheric processes and therefore an improved understanding of its daily variability is desirable. With the availability of high resolution, good quality Michelson Interferometer for Passive Atmospheric Sounding (MIPAS water vapour profiles, the ability of four different atmospheric models to assimilate these data is tested. MIPAS data have been assimilated over September 2003 into the models of the European Centre for Medium Range Weather Forecasts (ECMWF, the Belgian Institute for Space and Aeronomy (BIRA-IASB, the French Service d'Aéronomie (SA-IPSL and the UK Met Office. The resultant middle atmosphere humidity analyses are compared against independent satellite data from the Halogen Occultation Experiment (HALOE, the Polar Ozone and Aerosol Measurement (POAM III and the Stratospheric Aerosol and Gas Experiment (SAGE II. The MIPAS water vapour profiles are generally well assimilated in the ECMWF, BIRA-IASB and SA systems, producing stratosphere-mesosphere water vapour fields where the main features compare favourably with the independent observations. However, the models are less capable of assimilating the MIPAS data where water vapour values are locally extreme or in regions of strong humidity gradients, such as the southern hemisphere lower stratosphere polar vortex. Differences in the analyses can be attributed to the choice of humidity control variable, how the background error covariance matrix is generated, the model resolution and its complexity, the degree of quality control of the observations and the use of observations near the model boundaries. Due to the poor performance of the Met Office analyses the results are not included in

  11. The ASSET intercomparison of stratosphere and lower mesosphere humidity analyses

    Science.gov (United States)

    Thornton, H. E.; Jackson, D. R.; Bekki, S.; Bormann, N.; Errera, Q.; Geer, A. J.; Lahoz, W. A.; Rharmili, S.

    2009-02-01

    This paper presents results from the first detailed intercomparison of stratosphere-lower mesosphere water vapour analyses; it builds on earlier results from the EU funded framework V "Assimilation of ENVISAT Data" (ASSET) project. Stratospheric water vapour plays an important role in many key atmospheric processes and therefore an improved understanding of its daily variability is desirable. With the availability of high resolution, good quality Michelson Interferometer for Passive Atmospheric Sounding (MIPAS) water vapour profiles, the ability of four different atmospheric models to assimilate these data is tested. MIPAS data have been assimilated over September 2003 into the models of the European Centre for Medium Range Weather Forecasts (ECMWF), the Belgian Institute for Space and Aeronomy (BIRA-IASB), the French Service d'Aéronomie (SA-IPSL) and the UK Met Office. The resultant middle atmosphere humidity analyses are compared against independent satellite data from the Halogen Occultation Experiment (HALOE), the Polar Ozone and Aerosol Measurement (POAM III) and the Stratospheric Aerosol and Gas Experiment (SAGE II). The MIPAS water vapour profiles are generally well assimilated in the ECMWF, BIRA-IASB and SA systems, producing stratosphere-mesosphere water vapour fields where the main features compare favourably with the independent observations. However, the models are less capable of assimilating the MIPAS data where water vapour values are locally extreme or in regions of strong humidity gradients, such as the southern hemisphere lower stratosphere polar vortex. Differences in the analyses can be attributed to the choice of humidity control variable, how the background error covariance matrix is generated, the model resolution and its complexity, the degree of quality control of the observations and the use of observations near the model boundaries. Due to the poor performance of the Met Office analyses the results are not included in the intercomparison

  12. Blind intercomparison of nuclear models for predicting charged particle emission

    International Nuclear Information System (INIS)

    Shibata, K.; Cierjacks, S.

    1994-01-01

    Neutron activation data are important for dosimetry, radiation-damage and production of long-lived activities. For fusion energy applications, it is required to develop 'low-activation materials' from the viewpoints of safety, maintenance and waste disposal. Existing evaluated activation cross-section libraries are to a large extent based on nuclear-model calculations. The former Nuclear Energy Agency Nuclear Data Committee, NEANDC, (presently replaced by the NEA Nuclear Science Committee) organized the working group on activation cross sections. The first meeting of the group was held in 1989, and it was then agreed that a blind intercomparison of nuclear-model calculations should be undertaken in order to test the predictive power of the theoretical calculations. As a first stage the working group selected the reactions 60g Co(n,p) 60 Fe and 60m Co(n,p) 60 Fe, for which no experimental data were available, in the energy range from 1 to 20 MeV. The preliminary results compiled at the NEA Data Bank were sent to each participant and a meeting was held during the International Conference on Nuclear Data for Science and Technology in Julich 1991 to discuss the results. Following the outcome of the discussion in Julich, it was decided to extend this intercomparison. In the second-stage calculation, the same optical-model parameters were employed for neutrons, protons and α-particles, i.e., V = 50 MeV, W = 10 MeV, r = 1.25 fm and a = 0.6 fm with the Woods-Saxon volume-type form factors. No spin-orbit interaction was considered. Concerning the level density, the Fermi gas model with a = A/8 MeV -1 was assumed without pairing corrections. Moreover, gamma-ray competition was neglected to simplify the calculation. This report describes the final results of the blind comparison. Section 2 deals with a survey of the received contributions. The final results are graphically presented in section 3. 67 figs., 1 tab., 12 refs

  13. Intercomparison measurements of surface soil contamination with in-situ gamma ray spectrometry. Pt.1. Artificial radionuclides

    International Nuclear Information System (INIS)

    Winkelmann, I.

    1994-01-01

    This intercomparison program was performed by the Federal Office of Radiation Protection in October 1993. It includes seven laboratory teams from five countries and is applied on a pasture in southern Germany having an undisturbed soil profile. The location was chosen because of its relatively high 137 Cs-soil contamination caused by the Chernobyl accident - up to 50 kBq/m 2 . The deposition of 134 Cs and 137 Cs was determined. The comparison demonstrated a good agreement between results from different labs. Additionally, the dose rate at all marked locations was measured and compared to the dose rate of individual radionuclides calculated from the measured spectra. A relatively good agreement was obtained. It is shown that the main contribution to the total dose rate of 70 nSv/h is made by 137 Cs with a value of 5 nSv/h. 4 figs., 2 tabs., 3 refs. (orig.)

  14. Intercomparison of ionization chambers in standard X-ray beams, at radiotherapy, diagnostic radiology and radioprotection levels; Intercomparacao de camaras de ionizacao em feixes padroes de raios X, niveis radioterapia, radiodiagnostico e radioprotecao

    Energy Technology Data Exchange (ETDEWEB)

    Bessa, Ana Carolina Moreira de

    2006-07-01

    Since the calibration of radiation measurement instruments and the knowledge of their major characteristics are very important subjects, several different types of ionization chambers were intercompared in terms of their calibration coefficients and their energy dependence, in radiotherapy, diagnostic radiology and radioprotection standard beams. An intercomparison of radionuclide calibrators for nuclear medicine was performed, using three radionuclides: {sup 67}Ga, {sup 201}Tl and {sup 99m}Tc; the results obtained were all within the requirements of the national standard CNEN-NE-3.05. In order to complete the range of radiation qualities of the Calibration Laboratory of IPEN, standard radiation beam qualities, radiation protection and low energy radiation therapy levels, were established, according international recommendations. Three methodologies for the calibration of unsealed ionization chambers in X-ray beams were studied and compared. A set of Victoreen ionization chambers, specially designed for use in laboratorial intercomparisons, was submitted to characterization tests. The performance of these Victoreen ionization chambers showed that they are suitable for use in radioprotection beams, because the results obtained agree with international recommendations. However, these Victoreen ionization chambers can be used in radiotherapy and diagnostic radiology beams only with some considerations, since their performance in these beams, especially in relation to the energy dependence and stabilization time tests, did not agree with the international recommendations for dosimeters used in radiotherapy and diagnostic radiology beams. This work presents data on the performance of several types of ionization chambers in different X-ray beams, that may be useful for choosing the appropriate instrument for measurements in ionizing radiation beams. (author)

  15. Design and implementation of a ''cheese'' phantom-based Tomotherapy TLD dose intercomparison

    Energy Technology Data Exchange (ETDEWEB)

    Schiefer, Hans; Buchauer, Konrad; Heinze, Simon [Medical Physics Group, Department of Radiation Oncology, St. Gallen (Switzerland); Henke, Guido; Plasswilm, Ludwig [Department of Radiation Oncology, St. Gallen (Switzerland)

    2015-11-15

    The unique beam-delivery technique of Tomotherapy machines (Accuray Inc., Sunnyvale, Calif.) necessitates tailored quality assurance. This requirement also applies to external dose intercomparisons. Therefore, the aim of the 2014 SSRMP (Swiss Society of Radiobiology and Medical Physics) dosimetry intercomparison was to compare two set-ups with different phantoms. A small cylindrical Perspex phantom, which is similar to the IROC phantom (Imaging and Radiation Oncology Core, Houston, Tex.), and the ''cheese'' phantom, which is provided by the Tomotherapy manufacturer to all institutions, were used. The standard calibration plans for the TomoHelical and TomoDirect irradiation techniques were applied. These plans are routinely used for dose output calibration in Tomotherapy institutions. We tested 20 Tomotherapy machines in Germany and Switzerland. The ratio of the measured (D{sub m}) to the calculated (D{sub c}) dose was assessed for both phantoms and irradiation techniques. The D{sub m}/D{sub c} distributions were determined to compare the suitability of the measurement set-ups investigated. The standard deviations of the TLD-measured (thermoluminescent dosimetry) D{sub m}/D{sub c} ratios for the ''cheese'' phantom were 1.9 % for the TomoHelical (19 measurements) and 1.2 % (11 measurements) for the TomoDirect irradiation techniques. The corresponding ratios for the Perspex phantom were 2.8 % (18 measurements) and 1.8 % (11 measurements). Compared with the Perspex phantom-based set-up, the ''cheese'' phantom-based set-up without individual planning was demonstrated to be more suitable for Tomotherapy dose checks. Future SSRMP dosimetry intercomparisons for Tomotherapy machines will therefore be based on the ''cheese'' phantom set-up. (orig.) [German] Die einzigartige Bestrahlungstechnik mit Tomotherapie-Bestrahlungsgeraeten (Accuray Inc., Sunnyvale, CA, USA) erfordert spezifische

  16. ECAL Energy Flow Calibration

    CERN Multimedia

    CERN. Geneva

    2015-01-01

    My talk will be covering my work as a whole over the course of the semester. The focus will be on using energy flow calibration in ECAL to check the precision of the corrections made by the light monitoring system used to account for transparency loss within ECAL crystals due to radiation damage over time.

  17. Calibration with Absolute Shrinkage

    DEFF Research Database (Denmark)

    Øjelund, Henrik; Madsen, Henrik; Thyregod, Poul

    2001-01-01

    In this paper, penalized regression using the L-1 norm on the estimated parameters is proposed for chemometric je calibration. The algorithm is of the lasso type, introduced by Tibshirani in 1996 as a linear regression method with bound on the absolute length of the parameters, but a modification...

  18. Calibration bench of flowmeters

    International Nuclear Information System (INIS)

    Bremond, J.; Da Costa, D.; Calvet, A.; Vieuxmaire, C.

    1966-01-01

    This equipment is devoted to the comparison of signals from two turbines installed in the Cabri experimental loop. The signal is compared to the standard turbine. The characteristics and the performance of the calibration bench are presented. (A.L.B.)

  19. Calibration of farmer dosemeters

    International Nuclear Information System (INIS)

    Ahmad, S.S.; Anwar, K.; Arshed, W.; Mubarak, M.A.; Orfi, S.D.

    1984-08-01

    The Farmer Dosemeters of Atomic Energy Medical Centre (AEMC) Jamshoro were calibrated in the Secondary Standard Dosimetry Laboratory (SSDL) at PINSTECH, using the NPL Secondary Standard Therapy level X-ray exposure meter. The results are presented in this report. (authors)

  20. Physiotherapy ultrasound calibrations

    International Nuclear Information System (INIS)

    Gledhill, M.

    1996-01-01

    Calibration of physiotherapy ultrasound equipment has long been a problem. Numerous surveys around the world over the past 20 years have all found that only a low percentage of the units tested had an output within 30% of that indicatd. In New Zealand, a survey carried out by the NRL in 1985 found that only 24% had an output, at the maximum setting, within + or - 20% of that indicated. The present performance Standard for new equipment (NZS 3200.2.5:1992) requires that the measured output should not deviate from that indicated by more than + or - 30 %. This may be tightened to + or - 20% in the next few years. Any calibration is only as good as the calibration equipment. Some force balances can be tested with small weights to simulate the force exerted by an ultrasound beam, but with others this is not possible. For such balances, testing may only be feasible with a calibrated source which could be used like a transfer standard. (author). 4 refs., 3 figs

  1. Gamma ray calibration system

    International Nuclear Information System (INIS)

    Rosauer, P.J.; Flaherty, J.J.

    1981-01-01

    This invention is in the field of gamma ray inspection devices for tubular products and the like employing an improved calibrating block which prevents the sensing system from being overloaded when no tubular product is present, and also provides the operator with a means for visually detecting the presence of wall thicknesses which are less than a required minimum. (author)

  2. PLEIADES ABSOLUTE CALIBRATION : INFLIGHT CALIBRATION SITES AND METHODOLOGY

    Directory of Open Access Journals (Sweden)

    S. Lachérade

    2012-07-01

    Full Text Available In-flight calibration of space sensors once in orbit is a decisive step to be able to fulfil the mission objectives. This article presents the methods of the in-flight absolute calibration processed during the commissioning phase. Four In-flight calibration methods are used: absolute calibration, cross-calibration with reference sensors such as PARASOL or MERIS, multi-temporal monitoring and inter-bands calibration. These algorithms are based on acquisitions over natural targets such as African deserts, Antarctic sites, La Crau (Automatic calibration station and Oceans (Calibration over molecular scattering or also new extra-terrestrial sites such as the Moon and selected stars. After an overview of the instrument and a description of the calibration sites, it is pointed out how each method is able to address one or several aspects of the calibration. We focus on how these methods complete each other in their operational use, and how they help building a coherent set of information that addresses all aspects of in-orbit calibration. Finally, we present the perspectives that the high level of agility of PLEIADES offers for the improvement of its calibration and a better characterization of the calibration sites.

  3. Mercury CEM Calibration

    Energy Technology Data Exchange (ETDEWEB)

    John F. Schabron; Joseph F. Rovani; Susan S. Sorini

    2007-03-31

    The Clean Air Mercury Rule (CAMR) which was published in the Federal Register on May 18, 2005, requires that calibration of mercury continuous emissions monitors (CEMs) be performed with NIST-traceable standards. Western Research Institute (WRI) is working closely with the Electric Power Research Institute (EPRI), the National Institute of Standards and Technology (NIST), and the Environmental Protection Agency (EPA) to facilitate the development of the experimental criteria for a NIST traceability protocol for dynamic elemental mercury vapor generators. The traceability protocol will be written by EPA. Traceability will be based on the actual analysis of the output of each calibration unit at several concentration levels ranging from about 2-40 ug/m{sup 3}, and this analysis will be directly traceable to analyses by NIST using isotope dilution inductively coupled plasma/mass spectrometry (ID ICP/MS) through a chain of analyses linking the calibration unit in the power plant to the NIST ID ICP/MS. Prior to this project, NIST did not provide a recommended mercury vapor pressure equation or list mercury vapor pressure in its vapor pressure database. The NIST Physical and Chemical Properties Division in Boulder, Colorado was subcontracted under this project to study the issue in detail and to recommend a mercury vapor pressure equation that the vendors of mercury vapor pressure calibration units can use to calculate the elemental mercury vapor concentration in an equilibrium chamber at a particular temperature. As part of this study, a preliminary evaluation of calibration units from five vendors was made. The work was performed by NIST in Gaithersburg, MD and Joe Rovani from WRI who traveled to NIST as a Visiting Scientist.

  4. Latin-American Biological Dosimetry Network (LBDNET) Intercomparison Exercise. Evaluation through triage and conventional scoring criteria. Development of a new approach for statistical data analysis

    International Nuclear Information System (INIS)

    Di Giorgio, M.; Vallerga, M.B.; Radl, A.

    2011-01-01

    Biological Dosimetry is a necessary support for National Radiation Protection Programs and Emergency Response Schemes. A Latin-American Biological Dosimetry Network (LBDNET) has been constituted by the biological dosimetry laboratories from: Argentina, Brazil, Chile, Cuba, Mexico, Peru, and Uruguay (IAEA Regional Project RLA9/054, 2007). The biological dosimetry laboratory of Argentina organized an international biological dosimetry intercomparison for the analysis of some relevant parameters involved in dose assessment, to reinforce the response capability in accidental situations requiring the activation of mutual assistance mechanisms and thus, constituting the bases of the LBDNET organization. (authors)

  5. Acid aerosol measurement method intercomparisons: An outdoor smog chamber study

    International Nuclear Information System (INIS)

    Ellestad, T.G.; Barnes, H.M.; Kamens, R.M.; McDow, S.R.; Sickles, J.E. II; Hodson, L.L.; Waldman, J.M.; Randtke, S.J.; Lane, D.D.; Springston, S.R.; Koutrakis, P.; Thurston, G.D.

    1991-01-01

    A workshop on the measurement of acid aerosols indicated that the sampling methods in use had not been intercompared. Following two laboratory pilot studies, EPA sponsored tests in an outdoor smog chamber with a variety of test aerosols, including sulfuric acid only, photochemical smog with added sulfuric acid, photo-chemical smog with added sulfuric acid and dust, and dust followed by photochemical smog with added sulfuric acid. Two experiments of each type were conducted. Six groups, several of which were active in ambient acid aerosol measurements, participated by operating duplicate samplers for each experiment. Five groups employed a similar method, in which ammonia is removed from the sample stream by diffusion, particles are removed by Teflon filter, and hydrogen ion on the Teflon filter is determined by pH electrode. However, differences existed in the method's implementation among groups in physical design, flow rate, procedures, and analysis. The sixth group's method did not use a diffusion denuder for ammonia and had several other important differences. Besides hydrogen ion, seven other species were reported by most of the groups, including particle phase sulfate, ammonium, and nitrate, and gas phase sulfur dioxide, ammonia, nitric acid, and nitrous acid. Results of the inter-comparison will be presented

  6. RENEB intercomparisons applying the conventional Dicentric Chromosome Assay (DCA).

    Science.gov (United States)

    Oestreicher, Ursula; Samaga, Daniel; Ainsbury, Elizabeth; Antunes, Ana Catarina; Baeyens, Ans; Barrios, Leonardo; Beinke, Christina; Beukes, Philip; Blakely, William F; Cucu, Alexandra; De Amicis, Andrea; Depuydt, Julie; De Sanctis, Stefania; Di Giorgio, Marina; Dobos, Katalin; Dominguez, Inmaculada; Duy, Pham Ngoc; Espinoza, Marco E; Flegal, Farrah N; Figel, Markus; Garcia, Omar; Monteiro Gil, Octávia; Gregoire, Eric; Guerrero-Carbajal, C; Güçlü, İnci; Hadjidekova, Valeria; Hande, Prakash; Kulka, Ulrike; Lemon, Jennifer; Lindholm, Carita; Lista, Florigio; Lumniczky, Katalin; Martinez-Lopez, Wilner; Maznyk, Nataliya; Meschini, Roberta; M'kacher, Radia; Montoro, Alegria; Moquet, Jayne; Moreno, Mercedes; Noditi, Mihaela; Pajic, Jelena; Radl, Analía; Ricoul, Michelle; Romm, Horst; Roy, Laurence; Sabatier, Laure; Sebastià, Natividad; Slabbert, Jacobus; Sommer, Sylwester; Stuck Oliveira, Monica; Subramanian, Uma; Suto, Yumiko; Que, Tran; Testa, Antonella; Terzoudi, Georgia; Vral, Anne; Wilkins, Ruth; Yanti, LusiYanti; Zafiropoulos, Demetre; Wojcik, Andrzej

    2017-01-01

    Two quality controlled inter-laboratory exercises were organized within the EU project 'Realizing the European Network of Biodosimetry (RENEB)' to further optimize the dicentric chromosome assay (DCA) and to identify needs for training and harmonization activities within the RENEB network. The general study design included blood shipment, sample processing, analysis of chromosome aberrations and radiation dose assessment. After manual scoring of dicentric chromosomes in different cell numbers dose estimations and corresponding 95% confidence intervals were submitted by the participants. The shipment of blood samples to the partners in the European Community (EU) were performed successfully. Outside the EU unacceptable delays occurred. The results of the dose estimation demonstrate a very successful classification of the blood samples in medically relevant groups. In comparison to the 1st exercise the 2nd intercomparison showed an improvement in the accuracy of dose estimations especially for the high dose point. In case of a large-scale radiological incident, the pooling of ressources by networks can enhance the rapid classification of individuals in medically relevant treatment groups based on the DCA. The performance of the RENEB network as a whole has clearly benefited from harmonization processes and specific training activities for the network partners.

  7. An intercomparison of the thermal offset for different pyranometers

    Science.gov (United States)

    Sanchez, G.; Cancillo, M. L.; Serrano, A.

    2016-07-01

    An unprecedented intensive intercomparison campaign focused on the experimental measurement of the thermal offset of pyranometers has been conducted at Badajoz (Spain) with the participation of three main manufacturers. The purpose of this study is to compare the thermal offset of six commercially available pyranometers, being some of them widely used and others recently commercialized. In this campaign, the capping methodology has been used to experimentally measure the daytime thermal offset of the pyranometers. Thus, a short but intense campaign has been conducted in two selected summer days under clear-sky conditions, covering a large range of solar zenith angle, irradiance, and temperature. Along the campaign, a total of 305 capping events have been performed, 61 for each pyranometer. The daytime thermal offset obtained for different pyranometers ranges between 0 and -16.8 W/m2 depending on the environmental conditions, being sometimes notably higher than values estimated indoors by manufacturers. The thermal offset absolute value of all instruments shows a diurnal cycle, increasing from sunrise to central hours of the day and decreasing from midafternoon to sunset. The analysis demonstrates that thermal offset is notably higher and more variable during daytime than during nighttime, requiring specific daytime measurements. Main results emphasize the key role played by wind speed in modulating the thermal offset.

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

    CERN Document Server

    Caresana, M; 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

    2014-01-01

    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 instru...

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

    Energy Technology Data Exchange (ETDEWEB)

    Caresana, M., E-mail: marco.caresana@polimi.it [Politecnico di Milano, CESNEF, Dipartimento di Energia, via Ponzio 34/3, 20133 Milano (Italy); Denker, A. [Helmholtz-Zentrum Berlin für Materialien und Energie, Hahn-Meitner-Platz 1, D-14109 Berlin (Germany); Esposito, A. [IFNF-LNF, FISMEL, via E. Fermi 40, 00044 Frascati (Italy); Ferrarini, M. [CNAO, Via Privata Campeggi, 27100 Pavia (Italy); Golnik, N. [Institute of Metrology and Biomedical Engineering, Warsaw University of Technology, Sw. A. Boboli 8, 02-525 Warsaw (Poland); Hohmann, E. [Paul Scherrer Institut (PSI), Radiation Metrology Section, CH-5232 Villigen PSI (Switzerland); Leuschner, A. [Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, 22603 Hamburg (Germany); Luszik-Bhadra, M. [Physikalisch-Technische Bundesanstalt (PTB), Bundesallee 100, 38116 Braunschweig (Germany); Manessi, G. [CERN, 1211 Geneva 23 (Switzerland); University of Liverpool, Department of Physics, L69 7ZE Liverpool (United Kingdom); Mayer, S. [Paul Scherrer Institut (PSI), Radiation Metrology Section, CH-5232 Villigen PSI (Switzerland); Ott, K. [Helmholtz-Zentrum Berlin, BESSYII, Albert-Einstein-Str.15, 12489 Berlin (Germany); Röhrich, J. [Helmholtz-Zentrum Berlin für Materialien und Energie, Hahn-Meitner-Platz 1, D-14109 Berlin (Germany); Silari, M. [CERN, 1211 Geneva 23 (Switzerland); Trompier, F. [Institute for Radiological Protection and Nuclear Safety, F-92262 Fontenay aux Roses (France); Volnhals, M.; Wielunski, M. [Helmholtz Zentrum München, Ingolstädter Landstr. 1, D-85764 Neuherberg (Germany)

    2014-02-11

    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.

  10. A River Model Intercomparison Project in Preparation for SWOT

    Science.gov (United States)

    David, C. H.; Andreadis, K.; Famiglietti, J. S.; Beighley, E.; Boone, A. A.; Yamazaki, D.; Paiva, R. C. D.; Fleischmann, A. S.; Collischonn, W.; Fisher, C. K.; Kim, H.; Biancamaria, S.

    2017-12-01

    The Surface Water and Ocean Topography (SWOT) mission is currently scheduled to launch at the beginning of next decade. SWOT is expected to retrieve unprecedented measurements of water extent, elevation, and slope in the largest terrestrial water bodies. Such potential transformative information motivates the investigation of our ability to ingest the associated data into continental-scale models of terrestrial hydrology. In preparation for the expected SWOT observations, an inter-comparison of continental-scale river models is being performed. This comparison experiment focuses on four of the world's largest river basins: the Amazon, the Mississippi, the Niger, and the Saint-Lawrence. This ongoing project focuses on two main research questions: 1) How can we best prepare for the expected SWOT continental to global measurements before SWOT even flies?, and 2) What is the added value of including SWOT terrestrial measurements into global hydro models for enhancing our understanding of the terrestrial water cycle and the climate system? We present here the results of the second year of this project which now includes simulations from six numerical models of rivers over the Mississippi and sheds light on the implications of various modeling choices on simulation quality as well as on the potential impact of SWOT observations.

  11. A European neutron dosimetry intercomparison project (ENDIP). Results and evaluation

    International Nuclear Information System (INIS)

    Broerse, J.J.; Burger, G.; Coppola, M.

    1978-01-01

    A total of twenty groups from nine countries participated in sessions of the European Neutron Dosimetry Intercomparison Project (ENDIP) which were held during 1975 at GSF, Munich-Neuherberg and TNO, Rijswijk. The data of all participants are collected, the analysis and evaluation of the results are given in the present report. Specific chapters deal with the experimental arrangements and monitoring results at GSF and TNO, characteristics of the dosimetry systems employed by the paticipating groups and the basic physical data and correction factors employed for the determination of kerma and absorbed dose. In general, the participants in ENDIP quote systematic uncertainties of 7 to 8% in the neutron and total kerma or absorbed dose, which are mainly attributed to inadequate knowledge of basic constants. The variations in the results obtained by different participants seem to be in accordance with the relative large systematic uncertainties quoted. In order to determine the influence of the use of different values for the physical parameters, the relative responses of the participants' dosimeters have also been compared. The variances of quoted kerma and dose values are of the same order of magnitude as those of instrument responses. This result indicates inconsistencies in experimental techniques employed by the participants for the determination of kerma and absorbed dose. A separate nonparametric analysis of the ENDIP results confirmed that there are considerable systematic differences. Recommendations for future studies on neutron dosimetry for biological and medical applications are given at the end of the report

  12. Intercomparison of middle-atmospheric wind in observations and models

    Directory of Open Access Journals (Sweden)

    R. Rüfenacht

    2018-04-01

    Full Text Available Wind profile information throughout the entire upper stratosphere and lower mesosphere (USLM is important for the understanding of atmospheric dynamics but became available only recently, thanks to developments in remote sensing techniques and modelling approaches. However, as wind measurements from these altitudes are rare, such products have generally not yet been validated with (other observations. This paper presents the first long-term intercomparison of wind observations in the USLM by co-located microwave radiometer and lidar instruments at Andenes, Norway (69.3° N, 16.0° E. Good correspondence has been found at all altitudes for both horizontal wind components for nighttime as well as daylight conditions. Biases are mostly within the random errors and do not exceed 5–10 m s−1, which is less than 10 % of the typically encountered wind speeds. Moreover, comparisons of the observations with the major reanalyses and models covering this altitude range are shown, in particular with the recently released ERA5, ECMWF's first reanalysis to cover the whole USLM region. The agreement between models and observations is very good in general, but temporally limited occurrences of pronounced discrepancies (up to 40 m s−1 exist. In the article's Appendix the possibility of obtaining nighttime wind information about the mesopause region by means of microwave radiometry is investigated.

  13. Field calibration of cup anemometers

    DEFF Research Database (Denmark)

    Schmidt Paulsen, Uwe; Mortensen, Niels Gylling; Hansen, Jens Carsten

    2007-01-01

    A field calibration method and results are described along with the experience gained with the method. The cup anemometers to be calibrated are mounted in a row on a 10-m high rig and calibrated in the free wind against a reference cup anemometer. The method has been reported [1] to improve...... the statistical bias on the data relative to calibrations carried out in a wind tunnel. The methodology is sufficiently accurate for calibration of cup anemometers used for wind resource assessments and provides a simple, reliable and cost-effective solution to cup anemometer calibration, especially suited...

  14. Intercomparison of personnel dosimetry for thermal neutron dose equivalent in neutron and gamma-ray mixed fields

    International Nuclear Information System (INIS)

    Ogawa, Yoshihiro

    1985-01-01

    In order to consider the problems concerned with personnel dosimetry using film badges and TLDs, an intercomparison of personnel dosimetry, especially dose equivalent responses of personnel dosimeters to thermal neutron, was carried out in five different neutron and gamma-ray mixed fields at KUR and UTR-KINKI from the practical point of view. For the estimation of thermal neutron dose equivalent, it may be concluded that each personnel dosimeter has good performances in the precision, that is, the standard deviations in the measured values by individual dosimeter were within 24 %, and the dose equivalent responses to thermal neutron were almost independent on cadmium ratio and gamma-ray contamination. However, the relative thermal neutron dose equivalent of individual dosimeter normalized to the ICRP recommended value varied considerably and a difference of about 4 times was observed among the dosimeters. From the results obtained, it is suggested that the standardization of calibration factors and procedures is required from the practical point of radiation protection and safety. (author)

  15. Proposal of a postal system for Ir-192 sources calibration used in high dose rate brachytherapy with LiF:Mn:Ti thermoluminescent dosemeters; Proposta de um sistema postal para a calibracao de fontes de {sup 192} Ir, utilizadas em braquiterapia de alta taxa de dose, com dosimetros termoluminescentes de LiF: Mn: Ti

    Energy Technology Data Exchange (ETDEWEB)

    Vieira, W.S.; Borges, J.C.; Almeida, C.E.V. [Instituto de Radioprotecao e Dosimetria. CNEN Caixa Postal 37750, 22780-160, Rio de Janeiro (Brazil)

    1998-12-31

    A proposal in order to improve the brachytherapy quality control and to allow postal intercomparison of Ir-192 sources used in high dose rate brachytherapy has been presented. The LiF: Mn: Ti (TLD 100) detector has been selected for such purpose. The experimental array and the TLDs irradiation and calibration techniques, at the treatment units, have been specified in the light of more recent methodology of Ir-192 calibration sources. (Author)

  16. Optimization of procedure for calibration with radiometer/photometer

    International Nuclear Information System (INIS)

    Detilly, Isabelle

    2009-01-01

    A test procedure for the radiometer/photometer calibrations mark International Light at the Laboratorio de Fotometria y Tecnologia Laser (LAFTA) de la Escuela de Ingenieria Electrica de la Universidad de Costa Rica is established. Two photometric banks are used as experimental set and two calibrations were performed of the International Light. A basic procedure established in the laboratory, is used for calibration from measurements of illuminance and luminous intensity. Some dependent variations of photometric banks used in the calibration process, the programming of the radiometer/photometer and the applied methodology showed the results. The procedure for calibration with radiometer/photometer can be improved by optimizing the programming process of the measurement instrument and possible errors can be minimized by using the recommended procedure. (author) [es

  17. An improved calibration technique for measurement of 41Ar activity in gaseous effluents

    International Nuclear Information System (INIS)

    Jose, M.T.; Raghunath, V.M.

    1992-01-01

    One of the methods used generally for the calibration of a gaseous effluent monitoring system is to estimate the efficiency of the detector system with a point source of 22 Na. The uncertainty in this method is the assumption that a point source kept at a distance from the detector and a volume source nearer the detector will have the same efficiency. To overcome this problem, a technique of using 22 Na in liquid form has been standardised. The uncertainties in the strength of the liquid source is avoided by proper intercomparison of the same with a reference standard traceable to a primary standard. The NaI system has been calibrated for estimating the 41 Ar activity from the peak area counts in the MCA and SCA systems respectively. (author). 1 ref., 1 tab

  18. Evolution of Altimetry Calibration and Future Challenges

    Science.gov (United States)

    Fu, Lee-Lueng; Haines, Bruce J.

    2012-01-01

    Over the past 20 years, altimetry calibration has evolved from an engineering-oriented exercise to a multidisciplinary endeavor driving the state of the art. This evolution has been spurred by the developing promise of altimetry to capture the large-scale, but small-amplitude, changes of the ocean surface containing the expression of climate change. The scope of altimeter calibration/validation programs has expanded commensurately. Early efforts focused on determining a constant range bias and verifying basic compliance of the data products with mission requirements. Contemporary investigations capture, with increasing accuracies, the spatial and temporal characteristics of errors in all elements of the measurement system. Dedicated calibration sites still provide the fundamental service of estimating absolute bias, but also enable long-term monitoring of the sea-surface height and constituent measurements. The use of a network of island and coastal tide gauges has provided the best perspective on the measurement stability, and revealed temporal variations of altimeter measurement system drift. The cross-calibration between successive missions provided fundamentally new information on the performance of altimetry systems. Spatially and temporally correlated errors pose challenges for future missions, underscoring the importance of cross-calibration of new measurements against the established record.

  19. Industry guidelines for the calibration of maximum anemometers

    Energy Technology Data Exchange (ETDEWEB)

    Bailey, B.H. [AWS Scientific, Inc., Albany, NY (United States)

    1996-12-31

    The purpose of this paper is to report on a framework of guidelines for the calibration of the Maximum Type 40 anemometer. This anemometer model is the wind speed sensor of choice in the majority of wind resource assessment programs in the U.S. These guidelines were established by the Utility Wind Resource Assessment Program. In addition to providing guidelines for anemometers, the appropriate use of non-calibrated anemometers is also discussed. 14 refs., 1 tab.

  20. MAVEN SEP Calibrated Data Bundle

    Data.gov (United States)

    National Aeronautics and Space Administration — The maven.sep.calibrated Level 2 Science Data Bundle contains fully calibrated SEP data, as well as the raw count data from which they are derived, and ancillary...

  1. Ultrasonic calibration assembly

    International Nuclear Information System (INIS)

    1981-01-01

    Ultrasonic transducers for in-service inspection of nuclear reactor vessels have several problems associated with them which this invention seeks to overcome. The first is that of calibration or referencing a zero start point for the vertical axis of transducer movement to locate a weld defect. The second is that of verifying the positioning (vertically or at a predetermined angle). Thirdly there is the problem of ascertaining the speed per unit distance in the operating medium of the transducer beam prior to the actual inspection. The apparatus described is a calibration assembly which includes a fixed, generally spherical body having a surface for reflecting an ultrasonic beam from one of the transducers which can be moved until the reflection from the spherical body is the highest amplitude return signal indicating radial alignment from the body. (U.K.)

  2. Travelling gradient thermocouple calibration

    International Nuclear Information System (INIS)

    Broomfield, G.H.

    1975-01-01

    A short discussion of the origins of the thermocouple EMF is used to re-introduce the idea that the Peltier and Thompson effects are indistinguishable from one another. Thermocouples may be viewed as devices which generate an EMF at junctions or as integrators of EMF's developed in thermal gradients. The thermal gradient view is considered the more appropriate, because of its better accord with theory and behaviour, the correct approach to calibration, and investigation of service effects is immediately obvious. Inhomogeneities arise in thermocouples during manufacture and in service. The results of travelling gradient measurements are used to show that such effects are revealed with a resolution which depends on the length of the gradient although they may be masked during simple immersion calibration. Proposed tests on thermocouples irradiated in a nuclear reactor are discussed

  3. Mesoscale hybrid calibration artifact

    Science.gov (United States)

    Tran, Hy D.; Claudet, Andre A.; Oliver, Andrew D.

    2010-09-07

    A mesoscale calibration artifact, also called a hybrid artifact, suitable for hybrid dimensional measurement and the method for make the artifact. The hybrid artifact has structural characteristics that make it suitable for dimensional measurement in both vision-based systems and touch-probe-based systems. The hybrid artifact employs the intersection of bulk-micromachined planes to fabricate edges that are sharp to the nanometer level and intersecting planes with crystal-lattice-defined angles.

  4. Calibration of germanium detectors

    International Nuclear Information System (INIS)

    Bjurman, B.; Erlandsson, B.

    1985-01-01

    This paper describes problems concerning the calibration of germanium detectors for the measurement of gamma-radiation from environmental samples. It also contains a brief description of some ways of reducing the uncertainties concerning the activity determination. These uncertainties have many sources, such as counting statistics, full energy peak efficiency determination, density correction and radionuclide specific-coincidence effects, when environmental samples are investigated at close source-to-detector distances

  5. Calibration of hydrometers

    Science.gov (United States)

    Lorefice, Salvatore; Malengo, Andrea

    2006-10-01

    After a brief description of the different methods employed in periodic calibration of hydrometers used in most cases to measure the density of liquids in the range between 500 kg m-3 and 2000 kg m-3, particular emphasis is given to the multipoint procedure based on hydrostatic weighing, known as well as Cuckow's method. The features of the calibration apparatus and the procedure used at the INRiM (formerly IMGC-CNR) density laboratory have been considered to assess all relevant contributions involved in the calibration of different kinds of hydrometers. The uncertainty is strongly dependent on the kind of hydrometer; in particular, the results highlight the importance of the density of the reference buoyant liquid, the temperature of calibration and the skill of operator in the reading of the scale in the whole assessment of the uncertainty. It is also interesting to realize that for high-resolution hydrometers (division of 0.1 kg m-3), the uncertainty contribution of the density of the reference liquid is the main source of the total uncertainty, but its importance falls under about 50% for hydrometers with a division of 0.5 kg m-3 and becomes somewhat negligible for hydrometers with a division of 1 kg m-3, for which the reading uncertainty is the predominant part of the total uncertainty. At present the best INRiM result is obtained with commercially available hydrometers having a scale division of 0.1 kg m-3, for which the relative uncertainty is about 12 × 10-6.

  6. Dynamic photogrammetric calibration of industrial robots

    Science.gov (United States)

    Maas, Hans-Gerd

    1997-07-01

    Today's developments in industrial robots focus on aims like gain of flexibility, improvement of the interaction between robots and reduction of down-times. A very important method to achieve these goals are off-line programming techniques. In contrast to conventional teach-in-robot programming techniques, where sequences of actions are defined step-by- step via remote control on the real object, off-line programming techniques design complete robot (inter-)action programs in a CAD/CAM environment. This poses high requirements to the geometric accuracy of a robot. While the repeatability of robot poses in the teach-in mode is often better than 0.1 mm, the absolute pose accuracy potential of industrial robots is usually much worse due to tolerances, eccentricities, elasticities, play, wear-out, load, temperature and insufficient knowledge of model parameters for the transformation from poses into robot axis angles. This fact necessitates robot calibration techniques, including the formulation of a robot model describing kinematics and dynamics of the robot, and a measurement technique to provide reference data. Digital photogrammetry as an accurate, economic technique with realtime potential offers itself for this purpose. The paper analyzes the requirements posed to a measurement technique by industrial robot calibration tasks. After an overview on measurement techniques used for robot calibration purposes in the past, a photogrammetric robot calibration system based on off-the- shelf lowcost hardware components will be shown and results of pilot studies will be discussed. Besides aspects of accuracy, reliability and self-calibration in a fully automatic dynamic photogrammetric system, realtime capabilities are discussed. In the pilot studies, standard deviations of 0.05 - 0.25 mm in the three coordinate directions could be achieved over a robot work range of 1.7 X 1.5 X 1.0 m3. The realtime capabilities of the technique allow to go beyond kinematic robot

  7. Observation models in radiocarbon calibration

    International Nuclear Information System (INIS)

    Jones, M.D.; Nicholls, G.K.

    2001-01-01

    The observation model underlying any calibration process dictates the precise mathematical details of the calibration calculations. Accordingly it is important that an appropriate observation model is used. Here this is illustrated with reference to the use of reservoir offsets where the standard calibration approach is based on a different model to that which the practitioners clearly believe is being applied. This sort of error can give rise to significantly erroneous calibration results. (author). 12 refs., 1 fig

  8. Dosimetry and Calibration Section

    International Nuclear Information System (INIS)

    Otto, T.

    1998-01-01

    The two tasks of the Dosimetry and Calibration Section at CERN are the Individual Dosimetry Service which assures the personal monitoring of about 5000 persons potentially exposed to ionizing radiation at CERN, and the Calibration Laboratory which verifies all the instruments and monitors. This equipment is used by the sections of the RP Group for assuring radiation protection around CERN's accelerators, and by the Environmental Section of TISTE. In addition, nearly 250 electronic and 300 quartz fibre dosimeters, employed in operational dosimetry, are calibrated at least once a year. The Individual Dosimetry Service uses an extended database (INDOS) which contains information about all the individual doses ever received at CERN. For most of 1997 it was operated without the support of a database administrator as the technician who had assured this work retired. The Software Support Section of TIS-TE took over the technical responsibility of the database, but in view of the many other tasks of this Section and the lack of personnel, only a few interventions for solving immediate problems were possible

  9. Calibrated Properties Model

    International Nuclear Information System (INIS)

    Ghezzehej, T.

    2004-01-01

    The purpose of this model report is to document the calibrated properties model that provides calibrated property sets for unsaturated zone (UZ) flow and transport process models (UZ models). The calibration of the property sets is performed through inverse modeling. This work followed, and was planned in, ''Technical Work Plan (TWP) for: Unsaturated Zone Flow Analysis and Model Report Integration'' (BSC 2004 [DIRS 169654], Sections 1.2.6 and 2.1.1.6). Direct inputs to this model report were derived from the following upstream analysis and model reports: ''Analysis of Hydrologic Properties Data'' (BSC 2004 [DIRS 170038]); ''Development of Numerical Grids for UZ Flow and Transport Modeling'' (BSC 2004 [DIRS 169855]); ''Simulation of Net Infiltration for Present-Day and Potential Future Climates'' (BSC 2004 [DIRS 170007]); ''Geologic Framework Model'' (GFM2000) (BSC 2004 [DIRS 170029]). Additionally, this model report incorporates errata of the previous version and closure of the Key Technical Issue agreement TSPAI 3.26 (Section 6.2.2 and Appendix B), and it is revised for improved transparency

  10. The Cabauw Intercomparison campaign for Nitrogen Dioxide measuring Instruments (CINDI: design, execution, and early results

    Directory of Open Access Journals (Sweden)

    A. J. M. Piters

    2012-02-01

    Full Text Available From June to July 2009 more than thirty different in-situ and remote sensing instruments from all over the world participated in the Cabauw Intercomparison campaign for Nitrogen Dioxide measuring Instruments (CINDI. The campaign took place at KNMI's Cabauw Experimental Site for Atmospheric Research (CESAR in the Netherlands. Its main objectives were to determine the accuracy of state-of-the-art ground-based measurement techniques for the detection of atmospheric nitrogen dioxide (both in-situ and remote sensing, and to investigate their usability in satellite data validation. The expected outcomes are recommendations regarding the operation and calibration of such instruments, retrieval settings, and observation strategies for the use in ground-based networks for air quality monitoring and satellite data validation. Twenty-four optical spectrometers participated in the campaign, of which twenty-one had the capability to scan different elevation angles consecutively, the so-called Multi-axis DOAS systems, thereby collecting vertical profile information, in particular for nitrogen dioxide and aerosol. Various in-situ samplers and lidar instruments simultaneously characterized the variability of atmospheric trace gases and the physical properties of aerosol particles. A large data set of continuous measurements of these atmospheric constituents has been collected under various meteorological conditions and air pollution levels. Together with the permanent measurement capability at the CESAR site characterizing the meteorological state of the atmosphere, the CINDI campaign provided a comprehensive observational data set of atmospheric constituents in a highly polluted region of the world during summertime. First detailed comparisons performed with the CINDI data show that slant column measurements of NO2, O4 and HCHO with MAX-DOAS agree within 5 to 15%, vertical profiles of NO2 derived from several independent

  11. Last interglacial temperature evolution – a model inter-comparison

    Directory of Open Access Journals (Sweden)

    P. Bakker

    2013-03-01

    Full Text Available There is a growing number of proxy-based reconstructions detailing the climatic changes that occurred during the last interglacial period (LIG. This period is of special interest, because large parts of the globe were characterized by a warmer-than-present-day climate, making this period an interesting test bed for climate models in light of projected global warming. However, mainly because synchronizing the different palaeoclimatic records is difficult, there is no consensus on a global picture of LIG temperature changes. Here we present the first model inter-comparison of transient simulations covering the LIG period. By comparing the different simulations, we aim at investigating the common signal in the LIG temperature evolution, investigating the main driving forces behind it and at listing the climate feedbacks which cause the most apparent inter-model differences. The model inter-comparison shows a robust Northern Hemisphere July temperature evolution characterized by a maximum between 130–125 ka BP with temperatures 0.3 to 5.3 K above present day. A Southern Hemisphere July temperature maximum, −1.3 to 2.5 K at around 128 ka BP, is only found when changes in the greenhouse gas concentrations are included. The robustness of simulated January temperatures is large in the Southern Hemisphere and the mid-latitudes of the Northern Hemisphere. For these regions maximum January temperature anomalies of respectively −1 to 1.2 K and −0.8 to 2.1 K are simulated for the period after 121 ka BP. In both hemispheres these temperature maxima are in line with the maximum in local summer insolation. In a number of specific regions, a common temperature evolution is not found amongst the models. We show that this is related to feedbacks within the climate system which largely determine the simulated LIG temperature evolution in these regions. Firstly, in the Arctic region, changes in the summer sea-ice cover control the evolution of LIG winter

  12. EURADOS intercomparison on measurements and Monte Carlo modelling for the assessment of Americium in a USTUR leg phantom

    International Nuclear Information System (INIS)

    Lopez, M. A.; Broggio, D.; Capello, K.; Cardenas-Mendez, E.; El-Faramawy, N.; Franck, D.; James, A. C.; Kramer, G. H.; Lacerenza, G.; Lynch, T. P.; Navarro, J. F.; Navarro, T.; Perez, B.; Ruehm, W.; Tolmachev, S. Y.; Weitzenegger, E.

    2011-01-01

    A collaboration of the EURADOS working group on 'Internal Dosimetry' and the United States Transuranium and Uranium Registries (USTUR) has taken place to carry out an intercomparison on measurements and Monte Carlo modelling determining americium deposited in the bone of a USTUR leg phantom. Preliminary results and conclusions of this intercomparison exercise are presented here. (authors)

  13. Beta dosimetry using partial body dosimeters II. Results of intercomparison measurements of 1998/1999 - PTB report

    International Nuclear Information System (INIS)

    Ambrosi, P.; Helmstaedter, K.

    2000-12-01

    In 1998 the PTB organised a second series of intercomparison measurements for selected beta dosimeters worn on the extremities. In April 1999 these intercomparison measurements and the results obtained were discussed in a one day meeting. The contributions given and the results obtained and the conclusions drawn after extensive discussions are presented in this PTB report. (orig.) [de

  14. Results of the eruptive column model inter-comparison study

    Science.gov (United States)

    Costa, Antonio; Suzuki, Yujiro; Cerminara, M.; Devenish, Ben J.; Esposti Ongaro, T.; Herzog, Michael; Van Eaton, Alexa; Denby, L.C.; Bursik, Marcus; de' Michieli Vitturi, Mattia; Engwell, S.; Neri, Augusto; Barsotti, Sara; Folch, Arnau; Macedonio, Giovanni; Girault, F.; Carazzo, G.; Tait, S.; Kaminski, E.; Mastin, Larry G.; Woodhouse, Mark J.; Phillips, Jeremy C.; Hogg, Andrew J.; Degruyter, Wim; Bonadonna, Costanza

    2016-01-01

    This study compares and evaluates one-dimensional (1D) and three-dimensional (3D) numerical models of volcanic eruption columns in a set of different inter-comparison exercises. The exercises were designed as a blind test in which a set of common input parameters was given for two reference eruptions, representing a strong and a weak eruption column under different meteorological conditions. Comparing the results of the different models allows us to evaluate their capabilities and target areas for future improvement. Despite their different formulations, the 1D and 3D models provide reasonably consistent predictions of some of the key global descriptors of the volcanic plumes. Variability in plume height, estimated from the standard deviation of model predictions, is within ~ 20% for the weak plume and ~ 10% for the strong plume. Predictions of neutral buoyancy level are also in reasonably good agreement among the different models, with a standard deviation ranging from 9 to 19% (the latter for the weak plume in a windy atmosphere). Overall, these discrepancies are in the range of observational uncertainty of column height. However, there are important differences amongst models in terms of local properties along the plume axis, particularly for the strong plume. Our analysis suggests that the simplified treatment of entrainment in 1D models is adequate to resolve the general behaviour of the weak plume. However, it is inadequate to capture complex features of the strong plume, such as large vortices, partial column collapse, or gravitational fountaining that strongly enhance entrainment in the lower atmosphere. We conclude that there is a need to more accurately quantify entrainment rates, improve the representation of plume radius, and incorporate the effects of column instability in future versions of 1D volcanic plume models.

  15. Comparing apples and oranges: the Community Intercomparison Suite

    Science.gov (United States)

    Schutgens, Nick; Stier, Philip; Kershaw, Philip; Pascoe, Stephen

    2015-04-01

    Visual representation and comparison of geoscientific datasets presents a huge challenge due to the large variety of file formats and spatio-temporal sampling of data (be they observations or simulations). The Community Intercomparison Suite attempts to greatly simplify these tasks for users by offering an intelligent but simple command line tool for visualisation and colocation of diverse datasets. In addition, CIS can subset and aggregate large datasets into smaller more manageable datasets. Our philosophy is to remove as much as possible the need for specialist knowledge by the user of the structure of a dataset. The colocation of observations with model data is as simple as: "cis col ::" which will resample the simulation data to the spatio-temporal sampling of the observations, contingent on a few user-defined options that specify a resampling kernel. As an example, we apply CIS to a case study of biomass burning aerosol from the Congo. Remote sensing observations, in-situe observations and model data are shown in various plots, with the purpose of either comparing different datasets or integrating them into a single comprehensive picture. CIS can deal with both gridded and ungridded datasets of 2, 3 or 4 spatio-temporal dimensions. It can handle different spatial coordinates (e.g. longitude or distance, altitude or pressure level). CIS supports both HDF, netCDF and ASCII file formats. The suite is written in Python with entirely publicly available open source dependencies. Plug-ins allow a high degree of user-moddability. A web-based developer hub includes a manual and simple examples. CIS is developed as open source code by a specialist IT company under supervision of scientists from the University of Oxford and the Centre of Environmental Data Archival as part of investment in the JASMIN superdatacluster facility.

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

    Directory of Open Access Journals (Sweden)

    L. Hoffmann

    2014-12-01

    Full Text Available 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 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 5-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

  17. The sixth EULEP x-ray dosimetry intercomparison

    International Nuclear Information System (INIS)

    Aalbers, A.H.L.; Bader, F.J.M.

    1991-03-01

    During march-October 1989, the 6th EULEP X-Ray Dosimetry Inter-comparison on whole-body irradiation of mice was performed. It consisted of 2 irradiation series; the initial study comprised 15 participating institutes, the 2nd series was performed for 7 institutes which showed appreciable deviation from reference value. Mouse phantoms containing LiF:Mg,Ti thermoluminescent dosemeters (TLD-100 extruded ribbons) were mailed to participating institutes. In accordance with EULEP Protocol recommendations, participants performed irradiations using a procedure whereby the mouse phantom should receive an absorbed dose of 2Gy in muscle tissue at the central position. The read-out and evaluation of TL-dosemeters was performed at Dutch National Institute of Public Health and Environmental Protection (RIVM Bilthoven). The mean absorbed dose results in the centre of the phantom revealed that 10/15 participants agreed with the reference institute to within 5%. Somewhat larger deviations (±5-10%) were observed for 3 participants The remaining 2 participants showed discrepancies up to 15%. Uniform dose distributions over the mouse phantoms i.e. dose variations of ≤ 10% were observed for 10 participants. Four participants did not meet the recommended criterion for a uniform dose distribution, and one did not aim for uniform exposure conditions. Procedures followed to assess the comparability of dosimetry at different institutes cooperating within EULEP, are satisfactory with regard to the determination of absorbed dose and dose distribution. The deviations observed at 5 institutes indicate the need for site-visits to trace probable systematic errors. (author). 9 refs.; 10 figs.; 6 tabs

  18. Fennec dust forecast intercomparison over the Sahara in June 2011

    Directory of Open Access Journals (Sweden)

    J.-P. Chaboureau

    2016-06-01

    Full Text Available In the framework of the Fennec international programme, a field campaign was conducted in June 2011 over the western Sahara. It led to the first observational data set ever obtained that documents the dynamics, thermodynamics and composition of the Saharan atmospheric boundary layer (SABL under the influence of the heat low. In support to the aircraft operation, four dust forecasts were run daily at low and high resolutions with convection-parameterizing and convection-permitting models, respectively. The unique airborne and ground-based data sets allowed the first ever intercomparison of dust forecasts over the western Sahara. At monthly scale, large aerosol optical depths (AODs were forecast over the Sahara, a feature observed by satellite retrievals but with different magnitudes. The AOD intensity was correctly predicted by the high-resolution models, while it was underestimated by the low-resolution models. This was partly because of the generation of strong near-surface wind associated with thunderstorm-related density currents that could only be reproduced by models representing convection explicitly. Such models yield emissions mainly in the afternoon that dominate the total emission over the western fringes of the Adrar des Iforas and the Aïr Mountains in the high-resolution forecasts. Over the western Sahara, where the harmattan contributes up to 80 % of dust emission, all the models were successful in forecasting the deep well-mixed SABL. Some of them, however, missed the large near-surface dust concentration generated by density currents and low-level winds. This feature, observed repeatedly by the airborne lidar, was partly forecast by one high-resolution model only.

  19. Intercomparison of Aerosol Optical Depth from Brewer Ozone spectrophotometers and CIMEL sunphotometers measurements

    Directory of Open Access Journals (Sweden)

    A. Cheymol

    2009-01-01

    Full Text Available The Langley plot method applied on the Brewer Ozone measurements can provide accurate Aerosol Optical Depth (AOD in the UV-B. We present seven intercomparisons between AOD retrieved from Brewer Ozone measurements at 320 nm and AOD measured by CIMEL sunphotometer at 340 nm or 440 nm (shifted to 320 nm in using the Angström's law, which are stored in the international AERONET database. Only the intercomparisons between co-located instruments can be used to validate the Langley Plot Method applied to the Brewer measurements: in this case, all the correlation coefficients are above 0.82. If the instruments are not at the same site, the correlation between the AOD retrieved by both instruments is much lower. In applying the Angström's law the intercomparison is improved compared to previous study.

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

    International Nuclear Information System (INIS)

    Benedik, L.

    2013-01-01

    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. - Highlights: • The goal of this study is an overview of results obtained in intercomparison exercises for determination of actinides. • The disagreement of results for Np-237 was evaluated. • Improvements in separation procedures were done