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Sample records for cesium-137 teletherapy sources

  1. The effects of using Cesium-137 teletherapy sources as a radiological weapon (dirty bomb)

    CERN Document Server

    Liolios, Theodore

    2009-01-01

    While radioactive sources used in medical diagnosis do not pose a great security risk due to their low level of radioactivity, therapeutic sources are extremely radioactive and can presumably be used as a radiological weapon. Cobalt-60 and Cesium-137 sources are the most common ones used in radiotherapy with over 10,000 of such sources currently in use worldwide, especially in the developing world, which cannot afford modern accelerators. The present study uses computer simulations to investigate the effects of using Cesium-137 sources from teletherapy devices as a radiological weapon. Assuming a worst-case terrorist attack scenario, we estimate the ensuing cancer mortality, land contamination, evacuation area, as well as the relevant evacuation, decontamination, and health costs in the framework of the linear risk model. The results indicate that an attack with a Cesium-137 dirty bomb in a large metropolitan city (especially one that would involve several teletherapy sources) although would not cause any sta...

  2. The effects of using Cesium-137 teletherapy sources as a radiological weapon (dirty bomb)

    OpenAIRE

    Liolios, Theodore

    2009-01-01

    While radioactive sources used in medical diagnosis do not pose a great security risk due to their low level of radioactivity, therapeutic sources are extremely radioactive and can presumably be used as a radiological weapon. Cobalt-60 and Cesium-137 sources are the most common ones used in radiotherapy with over 10,000 of such sources currently in use worldwide, especially in the developing world, which cannot afford modern accelerators. The present study uses computer simulations to investi...

  3. Fabrication of cesium-137 brachytherapy sources using vitrification technology.

    Science.gov (United States)

    Dash, Ashutosh; Varma, R N; Ram, Ramu; Saxena, S K; Mathakar, A R; Avhad, B G; Sastry, K V S; Sangurdekar, P R; Venkatesh, Meera

    2009-08-01

    137Cs source in solid matrix encapsulated in stainless-steel at MBq (mCi) levels are widely used as brachytherapy sources for the treatment of carcinoma of cervix uteri. This article describes the large-scale preparation of such sources. The process of fabrication includes vitrification of 137Cs-sodium borosilicate glass, its transformation into spheres of 5-6 mm diameter, casting of glass spheres into a cylinder of 1.5 mm (varphi) x 80 mm (l) in a platinum mould, cutting of the moulds into 5-mm-long pieces, silver coating on the sources, and finally, encapsulation in stainless steel capsules. Development of safety precautions used to trap 137Cs escaping during borosilicate glass preparation is also described. The leach rates of the radioactive sources prepared by the above technology were within permissible limits, and the sources could be used for encapsulation in stainless steel capsules and supplied for brachytherapy applications. This development was aimed at promoting the potential utility of 137Cs-brachytherapy sources in the country and reducing the user's reliance on imported sources. Since its development, more than 1000 such sources have been made by using 4.66 TBq(126 Ci) of 137Cs.

  4. Dosimetry of IRIDIUM-192 and CESIUM-137 Seed Sources.

    Science.gov (United States)

    Thomason, Cynthia

    The use of ^{192}Ir in brachytherapy implants both alone and in conjunction with other modalities for the treatment of various types of cancer has greatly increased in recent years. This increased usage has led to a greater need for detailed information concerning the dose distribution surrounding commerically available ^{192} Ir seed sources. This is especially truce since improvements in computer technology along with their increased availability and utilization have enabled more precise calculation of dose distributions. The radiation does distribution in water was measured using LiF thermoluminescent dosimeters for an ^{192}Ir seed source with platinum encapsulation, for an ^{192}Ir seed source with stainless steel encapsulation and for a ^{137}Cs seed source intended as a substitute for ^{192 }Ir. The Electron-Gamma-Shower (EGS) computer code, which is a package for doing Monte Carlo simulation of the transport of photons and electrons in any medium or geometry specified by the user, also was used to study the dose distribution around these seed sources. In addition, the exposure rate constant, exposure rate at 1 meter, transmission through the source capsule, f-factor, and energy distribution exiting the source capsule were evaluated by Monte Carlo simulation of these three sources. Good agreement was seen between the measured data and the Monte Carlo generated data. In addition to producing valuable dosimetric data, this study has demonstrated that Monte Carlo modeling of ^{192} Ir and ^{137}Cs seed sources using the EGS Monte Carlo code can provide an accurate means of evaluating these data.

  5. Dosimetry of a Cesium 137 source; Dosimetria de una fuente de Cesio 137

    Energy Technology Data Exchange (ETDEWEB)

    Torres R, J.G.; Manzanares A, E.; Vega C, H.R. [Unidades Academicas de Estudios Nucleares, Universidad de Zacatecas (Mexico)

    2005-07-01

    It was carried out a dosimetric study of a source of Cesium 137 used in investigations of Radiobiology. This radionuclide has a half life of 30.07 years and it emits photons of 661.657 keV with a probability of 85.2%. The source has been used in a series of experiments trending to observe the cellular response before the gamma rays, as well as for the calibration of equipment of radiological protection. For such reason it is important to determine the dosimetric properties. In this work it was determined the absorbed dose that this source takes when being placed in the center from a methylmethacrylate badge to three distances, 5, 10 and 15 cm. The dose was measured with thermoluminescent dosemeters and it was calculated by means of Monte Carlo method, also was derived an expression that allows to determine the dose starting from the information of the activity of the source and of the distance regarding the same one. (Author)

  6. Interaction of radiation-generated free radicals with collagen and metalloproteins using cesium-137 gamma source

    Science.gov (United States)

    Shieh, James J.; Wierbicki, Eugen

    The interaction of collagen and metalloproteins with radiation-generated radicals has been studied using spectrophotometric, chromatographic, and ESR techniques. The hydroxyl radical (·OH) reacted with and caused polymerization of acid soluble collagen. Similar reactions were also observed in a ferrimyoglobin and cytochrome C system. Insoluble collagen from bovine muscle subjected to radiation is followed by a first-order process for the decay of free radicals, depending on relative humidity of the system. When the samples were irradiated with 3 kGy at 25°C by a Cesium-137 Irradiator, the observed half life (hr) of free radicals in the samples decreased with increase of relative humidity RH: 31% > 69% > 100%. When collagen, previously kept dry or under 31% RH, was irradiated with 3 kGy at 77°K (-196°C), the decay of free radicals reached a plateau with annealing at -120°C or higher. The decay kept decreasing with annealing at -100°C or higher temperature when collagen maintained at 69 and 100% RH was used. It is concluded that the free radicals in moistened collagen from bovine muscle decreased at a higher rate than in dried collagen. This suggests that free radicals may persist for a longer period of time in irradiated dry proteins of food or animal feed than in foods of higher moisture extent.

  7. Adaptation and security validation of an irradiator suitable for use of cesium-137 sources

    Directory of Open Access Journals (Sweden)

    Silva Rogério M.V.

    2014-03-01

    Full Text Available With the aim of offering a new application for 137Cs sources that were previously used in brachytherapy, we developed an irradiator for TL and OSL dosimeters by adapting a shielded storage container; this irradiator was named SOPHIA. It was assembled from a cubic iron casing, filled with lead, with external dimensions of 25 × 25 × 25 cm3. It has three different drawers with two sample holders suitable for samples or dosimeters with dimensions of up to 2 cm. Dose distribution of the surface of sample holder was obtained with EBT-3 radiochromic film and detectors thermoluminescent CaSO4: Dy. Regarding the security conditions of irradiation, the whole routine procedure for placement and removal of samples was simulated using Monte Carlo code. The equipment presented proper security conditions and the doses received by users during procedures for placement and extraction of the samples are in accordance with international standards.

  8. Cesium-137 Decorporation Model

    Science.gov (United States)

    2014-10-01

    thermochemical) 4.184 000 joule (J) cal (thermochemical)/cm2 4.184 000 x E-2 mega joule/m2 (MJ/m2) curie 3.7000 000 x E + 1 giga becquerel (GBq)* degree...for blood irradiation or for use in research. Irradiators using Cs sources are common in hospitals, blood banks , universities and other research

  9. Dating of mine waste in lacustrine sediments using cesium-137

    Science.gov (United States)

    Rember, W. C.; Erdman, T. W.; Hoffmann, M. L.; Chamberlain, V. E.; Sprenke, K. F.

    1993-11-01

    For over a century Medicine Lake in northern Idaho has received heavy-metal-laden tailings from the Coeur d'Alene mining district. Establishing the depositional chronology of the lake bottom sediments provides information on the source and rate of deposition of the tailings. Cesium-137, an isotope produced in the atmosphere by nuclear bomb tests, was virtually absent in the environment prior to 1951, but reached its apex in 1964. Our analysis of cesium-137 in the sediments of Medicine Lake revealed that 14 cm of fine-grained tailings were deposited in the lake from 1951 to 1964 and tailing deposition downstream was greatly reduced by the installation of tailings dams in the district in 1968. Cesium-137 analysis is accomplished by a fairly simple gamma-ray counting technique and should be a valuable tool for analyzing sedimentation in any lacustrine environment that was active during the 1950s and 1960s.

  10. Decorporation of cesium-137; Decorporation du cesium-137

    Energy Technology Data Exchange (ETDEWEB)

    Le Fleche, Ph.; Destombe, C.; Grasseau, A.; Mathieu, J.; Chancerelle, Y.; Mestries, J.C. [GMR, Direction des Recherches, Etudes et Techniques, 94 - Arcueil (France)

    1997-12-31

    Cesium radio-isotopes, especially cesium-137 ({sup 137}Cs) are among the radionuclides of main importance produced by a fission reaction in reactor or a nuclear weapon explosion. In the environment, {sup 137}Cs is a major contaminant which can cause severe {beta}, {gamma}irradiations and contaminations. {sup 137}Cs is distributed widely and relatively uniformly throughout the body with the highest concentration in skeletal muscles. A treatment becomes difficult afterwards. The purposes of this report are Firstly to compare the Prussian blue verses cobalt and potassium ferrocyanide (D.I. blue) efficiency for the {sup 137}Cs decorporation and secondly to assess a chronological treatment with D.I. blue. (author)

  11. Derivation of cesium-137 residual radioactive material guidelines for the Peek Street site, Schenectady, New York

    Energy Technology Data Exchange (ETDEWEB)

    Jones, L.; Nimmagadda, M.; Yu, C.

    1992-01-01

    Residual radioactive material guidelines for cesium-137 were derived for the Peek rk. The derivation was based on the requirement that the Street site in Schenectady, New York. The derivation was based on the requirement that the 50-year committed effective dose equivalent to a hypothetical individual who lives or works in the immediate vicinity of the Peek Street site should not exceed a dose of 100 mrem/yr following remedial action. The US Department of Energy (DOE) residual radioactive material guideline computer code, RESRAD was used in this evaluation. Three potential scenarios were considered for the site on the assumption that for a period of 1,000 years following remedial action, the site wig be utilized without radiological restrictions. The scenarios vary with regard to use of the site, time spent at the site, and sources of food consumed. Results indicate that the basic dose limit of 100 mrem/yr will not be exceeded for cesium-137 within 1,000 years, provided that the soil concentration of cesium-137 at the Peek Street site does not exceed the following levels: 98 pCi/g for Scenario A (industrial worker: the expected scenario), 240 pCi/g for Scenario B (recreationist: a plausible scenario), and 34 pCi/g for Scenario C (resident farmer ingesting food produced in the decontaminated area: a plausible scenario).

  12. Cesium-137 Levels Detected in Otters from Austria

    Directory of Open Access Journals (Sweden)

    Gutleb A.C.

    1991-02-01

    Full Text Available Pollution seems to be one of the most important causes for the decline of the European otter (Lutra lutra. The accident in the Chernobyl nuclear power plant added another aspect to environmental pollution. Few data on cesium-137 contents in otters are available, so levels were measured in 3 otters from Austria. All levels found were very low.

  13. Cesium-137, a drama recounted; Cesio-137, um drama recontado

    Energy Technology Data Exchange (ETDEWEB)

    Vieira, Suzane de Alencar

    2013-01-15

    The radiological accident with Cesium-137, which started on Goiania in 1987, did not stop with the end of radiological contamination and continues in a judicial, scientific and narrative process of identification and recognition of new victims. The drama occupies a central place on the dynamics of radiological event, as it extends its limits, inflects its intensity and updates the event. As a narrative of the event, the ethnography incorporates and brings up to date the drama as an analysis landmark and the description of the theme as it is absorbed by a dramatic process. Cesium-137, a drama recounted is a textual experimentation based on real events and characters picked out from statements reported in various narratives about the radiological accident. (author)

  14. Cobalt-60 and cesium-137 for the sterilization of food. Radiation treatment of food. Mit Kobalt 60 und Caesium 137 gegen Keime in Lebensmitteln. Strahlenbehandlung von Lebensmitteln

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    1990-11-01

    The brief article discusses the reasons justifying in the eyes of the authors the irradiation of food with ionizing readiation, the irradiation technique applied using cobalt-60 and cesium-137 as a radiation source, and the possible secondary effects of the method. (VHE).

  15. Mercury and cesium-137 in urban gray squirrels

    Energy Technology Data Exchange (ETDEWEB)

    Jenkins, J.H. (Univ. of Georgia, Athens); Davis, A.H.; Bigler, W.J.; Hoff, G.L.

    1980-08-01

    Recent emphasis upon the revitalization of major cities has underscored a need for urban wildlife management. Intensive management of the wildlife populations indigenous to metropolitan areas will enhance our quality of life in many ways. One important benefit is that certain species can serve as sensitive indicators of environmental change. The gray squirrel (Sciurus carolinensis) is usually abundant in cities and they are often subject to a variety of destructive environmental factors. In an attempt to evaluate the gray squirrel as an indicator of zoonoses and pollutants, the Health Program Office of the Department of Health and Rehabilitative Services conducted a multifaceted study in Jacksonvlle, Florida during 1974. This report presents baseline measurements of body burdens of mercury and cesium-137.

  16. Hanford Isotope Project strategic business analysis Cesium-137 (Cs-137)

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-10-01

    The purpose of this business analysis is to address the beneficial reuse of Cesium 137 (Cs-137) in order to utilize a valuable national asset and possibly save millions of tax dollars. Food irradiation is the front runner application along with other uses. This business analysis supports the objectives of the Department of Energy National Isotope Strategy distributed in August 1994 which describes the DOE plans for the production and distribution of isotope products and services. As part of the Department`s mission as stated in that document. ``The Department of Energy will also continue to produce and distribute other radioisotopes and enriched stable isotopes for medical diagnostics and therapeutics, industrial, agricultural, and other useful applications on a businesslike basis. This is consistent with the goals and objectives of the National Performance Review. The Department will endeavor to look at opportunities for private sector to co-fund or invest in new ventures. Also, the Department will seek to divest from ventures that can more profitably or reliably be operated by the private sector.``

  17. Total deposition of cesium-137 measured in Finland during the exercise `RESUME 95` in August 1995

    Energy Technology Data Exchange (ETDEWEB)

    Geer, L.E. De; Vintersved, I.; Arntsing, R. [National Defence Research Establisment, Nuclear Detection Group, Stockholm (Sweden)

    1997-12-31

    In the exercise called `RESUME 95` the Nuclear Detection Group from the National Defence Research Establishment in Stockholm participated with field gamma ray measurements combined with soil sampling and profile measurements. The results are presented in this report for the measurements of cesium-137. We considered the measurements of cesium-137 at the airfield the most important part of the in-situ exercise. Data was of course collected also for cesium-134 and natural radionuclides but time has not permitted a full analysis of these radionuclides. The methodology would, however, be the same as applied for cesium-137. Less attention was paid for area II and due to limited personnel resources the search exercise was not fully carried out. (au).

  18. Deciphering the measured ratios of Iodine-131 to Cesium-137 at the Fukushima reactors

    CERN Document Server

    Matsui, T

    2011-01-01

    We calculate the relative abundance of the radioactive isotopes Iodine-131 and Cesium-137 produced by nuclear fission in reactors and compare it with data taken at the troubled Fukushima Dai-ichi nuclear power plant. The ratio of radioactivities of these two isotopes can be used to obtain information about when the nuclear reactions terminated.

  19. [Improvement of gynecologic radium therapy through the afterloading method using cesium 137].

    Science.gov (United States)

    Fournier, D V; Senf, W; Kuttig, H; Kubli, F

    1976-03-01

    For all centers performing gynecological contact irradiation the use of afterloading techniques is urgently required, since they eliminate any radiation exposure to the personnel. The radio-therapist may position and control the empty applicators still free from radiation withoug haste. This procedure diminishes the occurrence of overdosages and underdosages. The care for the patients is possible without radiation exposure, and the morbidity of contact therapy can be reduced by occasional mobilization of the patient, the applicator without sources remaining at its place. The fully automatic apparatus "Curietron" using cesium-137 sources (0.662 MeV gamma emission, half-life period 26.6 years) with an equivalent source activity (factor 2.6) yields the dose distribution demanded in the gynecologic field which in practice is identical to that of Ra-226 (medium gamma emission 1 MeV, half-life period 1620 years). With similar dose distribution, a biological and therapeutical effect alike to Ra-226 may be expected from Cs-137. In comparison with Ra-226, the following advantages of Cs-137 may be mentioned: Lower half-value thickness of 5.5 mm lead (low expenses for radioprotection), less danger with handling (no emanation of radioactive gases), and lower contamination risks in case of breaking. The measured dose distributions at equivalent source activity and similar geometry of the applicators revealed the possibility with regard of all techniques of gynecologic irradiation utilized in our field of arriving at similar relative and absolute dose distributions by means of the Cs-137 afterloading technique. Whilst short-term afterloading irradiation with highly active sources, their radiobiological effectiveness being not yet ascertained, has to be tested at appropriate scientific centers, it is necessary to demand afterloading techniques with dosages and duration of irradiations approved over decades for all centers of gynecological contact therapy because of radiation

  20. Multi-decadal projections of surface and interior pathways of the Fukushima Cesium-137 radioactive plume

    Science.gov (United States)

    Rossi, Vincent; Van Sebille, Erik; Sen Gupta, Alexander; Garçon, Véronique; England, Matthew H.

    2013-10-01

    Following the March 2011 Fukushima disaster, large amounts of water contaminated with radionuclides, including Cesium-137, were released into the Pacific Ocean. With a half-life of 30.1 years, Cs-137 has the potential to travel large distances within the ocean. Using an ensemble of regional eddy-resolving simulations, this study investigates the long-term ventilation pathways of the leaked Cs-137 in the North Pacific Ocean. The simulations suggest that the contaminated plume would have been rapidly diluted below 10,000 Bq/m3 by the energetic Kuroshio Current and Kurushio Extension by July 2011. Based on our source function of 22 Bq/m3, which sits at the upper range of the published estimates, waters with Cs-137 concentrations >10 Bq/m3 are projected to reach the northwestern American coast and the Hawaiian archipelago by early 2014. Driven by quasi-zonal oceanic jets, shelf waters north of 45°N experience Cs-137 levels of 10-30 Bq/m3 between 2014 and 2020, while the Californian coast is projected to see lower concentrations (10-20 Bq/m3) slightly later (2016-2025). This late but prolonged exposure is related to subsurface pathways of mode waters, where Cs-137 is subducted toward the subtropics before being upwelled from deeper sources along the southern Californian coast. The model suggests that Fukushima-derived Cs-137 will penetrate the interior ocean and spread to other oceanic basins over the next two decades and beyond. The sensitivity of our results to uncertainties in the source function and to inter-annual to multi-decadal variability is discussed.

  1. Biological effects of cesium-137 injected in beagle dogs of different ages

    Energy Technology Data Exchange (ETDEWEB)

    Nikula, K.J.; Muggenburg, B.A.; Griffith, W.C. [and others

    1995-12-01

    The toxicity of cesium-137 ({sup 137}Cs) in the Beagle dog was investigated at the Argonne National Laboratory (ANL) as part of a program to evaluate the biological effects of internally deposited radionuclides. The toxicity and health effects of {sup 137}Cs are important to understand because {sup 137}Cs is produced in large amounts in light-water nuclear reactors. Large quantities of cesium radioisotopes have entered the human food chain as a result of atmospheric nuclear weapons test, and additional cesium radioisotopes were released during the Chernobyl accident. Although the final analyses are not complete, three findings are significant: older dogs dies significantly earlier than juvenile and young adult dogs; greater occurrence of sarcomas in the cesium-137 injected dogs; the major nonneoplastic effect in dogs surviving beyond 52 d appears to be testicular atrophy.

  2. Different cesium-137 transfers to forest and stream ecosystems.

    Science.gov (United States)

    Sakai, Masaru; Gomi, Takashi; Negishi, Junjiro N; Iwamoto, Aimu; Okada, Kengo

    2016-02-01

    Understanding the mechanisms of (137)Cs movement across different ecosystems is crucial for projecting the environmental impact and management of nuclear contamination events. Here, we report differential movement of (137)Cs in adjacent forest and stream ecosystems. The food webs of the forest and stream ecosystems in our study were similar, in that they were both dominated by detrital-based food webs and the basal energy source was terrestrial litter. However, the concentration of (137)Cs in stream litter was significantly lower than in forest litter, the result of (137)Cs leaching from litter in stream water. The difference in (137)Cs concentrations between the two types of litter was reflected in the (137)Cs concentrations in the animal community. While the importance of (137)Cs fallout and the associated transfer to food webs has been well studied, research has been primarily limited to cases in a single ecosystem. Our results indicate that there are differences in the flow of (137)Cs through terrestrial and aquatic ecosystems, and that (137)Cs concentrations are reduced in both basal food resources and higher trophic animals in aquatic systems, where primary production is subsidized by a neighboring terrestrial ecosystem.

  3. Use of cesium-137 methodology in the evaluation of superficial erosive processes

    Directory of Open Access Journals (Sweden)

    Avacir Casanova Andrello

    2003-06-01

    Full Text Available Superficial erosion is one of the main soil degradation agents and erosion rates estimations for different edaphicclimate conditions for the conventional models, as USLE and RUSLE, are expensive and time-consuming. The use of cesium-137 antrophogenic radionuclide is a new methodology that has been much studied and its application in the erosion soil evaluation has grown in countries as USA, UK, Australia and others. A brief narration of this methodology is being presented, as the development of the equations utilized for the erosion rates quantification through the cesium-137 measurements. Two watersheds studied in Brazil have shown that the cesium-137 methodology was practicable and coherent with the survey in field for applications in erosion studies.A erosão superficial é um dos principais agentes de degradação dos solos e estimativas das taxas de erosão para diferentes condições edafoclimáticas pelos modelos tradicionais como USLE, RUSLE, são onerosos e demorados. Uma metodologia que tem sido muito estudada e sua aplicação no estudo da erosão vem crescendo em países como EUA, Reino Unido, Austrália, e outros, é a do uso do radionuclídeo antropogênico césio-137. Um resumo da história desta metodologia é apresentado, assim como a evolução das equações utilizadas para quantificar as taxas de erosão através da medida do césio-137. Duas bacias estudadas no Brasil mostraram que a metodologia do césio-137 é viável e coerente com as observações em campo para aplicação no estudo da erosão.

  4. Distribution of global fallouts cesium-137 in taiga and tundra catenae at the Ob River basin

    Science.gov (United States)

    Semenkov, I. N.; Usacheva, A. A.; Miroshnikov, A. Yu.

    2015-03-01

    The classification of soil catenae at the Ob River basin is developed and applied. This classification reflects the diverse geochemical conditions that led to the formation of certain soil bodies, their combinations and the migration fields of chemical elements. The soil and geochemical diversity of the Ob River basin catenae was analyzed. The vertical and lateral distribution of global fallouts cesium-137 was studied using the example of the four most common catenae types in Western Siberia tundra and taiga. In landscapes of dwarf birches and dark coniferous forests on gleysols, cryosols, podzols, and cryic-stagnosols, the highest 137Cs activity density and specific activity are characteristic of the upper soil layer of over 30% ash, while the moss-grass-shrub cover is characterized by low 137Cs activity density and specific activity. In landscapes of dwarf birches and pine woods on podzols, the maximum specific activity of cesium-137 is typical for moss-grass-shrub cover, while the maximum reserves are concentrated in the upper soil layer of over 30% ash. Bog landscapes and moss-grass-shrub cover are characterized by a minimum activity of 137Cs, and its reserves in soil generally decrease exponentially with depth. The cesium-137 penetration depth increases in oligotrophic histosols from northern to middle taiga landscapes from 10-15 to 40 cm. 137Cs is accumulated in oligotrophic histosols for increases in pH from 3.3 to 4.0 and in concretionary interlayers of pisoplinthic-cryic-histic-stagnosols. Cryogenic movement, on the one hand, leads to burying organic layers enriched in 137Cs and, on the other hand, to deducing specific activity when mixed with low-active material from lower soil layers.

  5. Cesium-137 as a tracer of soil turbation: example of the taiga landscapes of the Western Siberia, Russia

    Energy Technology Data Exchange (ETDEWEB)

    Usacheva, Anna A.; Semenkov, Ivan N. [The Organization of Russian Academy of Sciences Institute of geology of ore deposits, petrography, mineralogy and geochemistry Russian Academy of Sciences, 119017, Moscow (Russian Federation)

    2014-07-01

    Cesium-137 is artificial radionuclide with 30.17 years half-life. However, this element can be found anywhere due to global atmospheric fallout. Its background storage is detected in landscapes: water, bottom sediments, plants and soils. Almost no one has studied the concentration of {sup 137}Cs in the landscapes of the North, because of its negligible storage. Cesium-137 is slightly mobile in the soils of the North. The cryogenic and other material movement is a typical feature of soils of the North. However, the dating of the soil turbations less than 100 years of age, using existing methods, is possible via long-term stationary observations. To determine the age of soil turbations quicker, one can use slightly mobile artificial radionuclides with medium or long half-life. Cesium-137 satisfies all the criteria. The aim of the work is to estimate suitable of cesium-137 as geo-tracer of soil turbation. According to our evaluation, the activity of the buried layers is less than 10 Bq*kg{sup -1} at the current {sup 137}Cs contamination of surface organic horizons (60-90 Bq*kg{sup -1}). A research has been conducted to study distribution of cesium-137 in the north and middle taiga landscapes of Western Siberia (Russia). Field research was carried out in 2012 in two study areas. The first study area 'Purpe' is located in the middle part of the Pur river basin, near Gubkinsky town (Yamalo-Nenets Autonomous Okrug). The second study area 'Noyabrsk' is located in the Ob and the Pur river watersheds, near Noyabrsk-city (Yamalo-Nenets Autonomous Okrug). Moss-grass-underwood layer (n=13) contains 22±20% of {sup 137}Cs total storage in the landscapes of oligo-trophic bogs with cryohistosols and pine forests on cryopodzols. The main reservoir of cesium-137 is soils (n=24) that accumulate 78±20% of its total landscape storage. The upper 10-cm soil layer contains 90% of {sup 137}Cs soil storage. Cesium-137 activity declines from shrubs and polytric layers

  6. Experimental contamination of pink shrimps by caesium 137; Contamination experimentale de crevettes roses par le cesium 137

    Energy Technology Data Exchange (ETDEWEB)

    Ancellin, J.; Michon, G.; Vilquin, A. [Commissariat a l' Energie Atomique, Fontenay-aux-Roses (France). Centre d' Etudes Nucleaires

    1965-07-01

    The authors describe first of all the technique used for the determination of cesium 137 concentration factors in the pink shrimp (Leander Serratus Pennant). Experiments over three months have shown that the specific activity of the shrimps becomes stable between the thirtieth and the fortieth day. The concentration factors then have values between 30 and 40. These results are similar to those obtained by other authors. (authors) [French] Les auteurs decrivent tout d'abord la technique utilisee pour la determination des facteurs de concentration du Cesium 137 chez la crevette rose (Leander Serratus Pennant). Le resultat des experimentations menees pendant trois mois montre que l'activite specifique des crevettes se stabilise entre le trentieme et le quarantieme jour. Les facteurs de concentration se situent alors entre 30 et 40, Ces donnees sont comparables a celles obtenues par d'autres auteurs. (auteur)

  7. European inter-comparison of Monte Carlo codes users for the uncertainty calculation of the kerma in air beside a caesium-137 source; Intercomparaison europeenne d'utilisateurs de codes monte carlo pour le calcul d'incertitudes sur le kerma dans l'air aupres d'une source de cesium-137

    Energy Technology Data Exchange (ETDEWEB)

    De Carlan, L.; Bordy, J.M.; Gouriou, J. [CEA Saclay, LIST, Laboratoire National Henri Becquerel, Laboratoire de Metrologie de la Dose 91 - Gif-sur-Yvette (France)

    2010-07-01

    Within the frame of the CONRAD European project (Coordination Network for Radiation Dosimetry), and more precisely within a work group paying attention to uncertainty assessment in computational dosimetry and aiming at comparing different approaches, the authors report the simulation of an irradiator containing a caesium 137 source to calculate the kerma in air as well as its uncertainty due to different parameters. They present the problem geometry, recall the studied issues (kerma uncertainty, influence of capsule source, influence of the collimator, influence of the air volume surrounding the source). They indicate the codes which have been used (MNCP, Fluka, Penelope, etc.) and discuss the obtained results for the first issue

  8. Development of urinary biomarkers for internal exposure by cesium-137 using a metabolomics approach in mice.

    Science.gov (United States)

    Goudarzi, Maryam; Weber, Waylon; Mak, Tytus D; Chung, Juijung; Doyle-Eisele, Melanie; Melo, Dunstana; Brenner, David J; Guilmette, Raymond A; Fornace, Albert J

    2014-01-01

    Cesium-137 is a fission product of uranium and plutonium in nuclear reactors and is released in large quantities during nuclear explosions or detonation of an improvised device containing this isotope. This environmentally persistent radionuclide undergoes radioactive decay with the emission of beta particles as well as gamma radiation. Exposure to (137)Cs at high doses can cause acute radiation sickness and increase risk for cancer and death. The serious health risks associated with (137)Cs exposure makes it critical to understand how it affects human metabolism and whether minimally invasive and easily accessible samples such as urine and serum can be used to triage patients in case of a nuclear disaster or a radiologic event. In this study, we have focused on establishing a time-dependent metabolomic profile for urine collected from mice injected with (137)CsCl. The samples were collected from control and exposed mice on days 2, 5, 20 and 30 after injection. The samples were then analyzed by ultra-performance liquid chromatography coupled to time-of-flight mass spectrometry (UPLC/TOFMS) and processed by an array of informatics and statistical tools. A total of 1,412 features were identified in ESI(+) and ESI(-) modes from which 200 were determined to contribute significantly to the separation of metabolomic profiles of controls from those of the different treatment time points. The results of this study highlight the ease of use of the UPLC/TOFMS platform in finding urinary biomarkers for (137)Cs exposure. Pathway analysis of the statistically significant metabolites suggests perturbations in several amino acid and fatty acid metabolism pathways. The results also indicate that (137)Cs exposure causes: similar changes in the urinary excretion levels of taurine and citrate as seen with external-beam gamma radiation; causes no attenuation in the levels of hexanoylglycine and N-acetylspermidine; and has unique effects on the levels of isovalerylglycine and

  9. Introduce lichen Lepraria incana as biomonitor of Cesium-137 from Ramsar, northern Iran.

    Science.gov (United States)

    Dalvand, Amin; Jahangiri, Ahmad; Iranmanesh, Jalil

    2016-08-01

    Lichens have been used as biomonitors of airborne radionuclides released in conjunction with nuclear bomb testing as well as nuclear power plant accidents. The potential of lichens for monitoringof radionuclides has been well documented. However, there are no studies that determine natural and artificial radionuclide monitoring by lichens, in Iran. Thus, as a first step, we have conducted a comparison of (137)Csactivity concentration capacity of three epiphytic lichen species including Lepraria incana, Xanthoria parietina and Ramalina farinacea from Ramsar Northern Iran. In this work, accumulation capacity of (137)Cs was determined in 36 lichen samples using a gamma spectrometer equipped with a high purity germanium (HPGe) detector. The results showed that highest accumulation capacity of (137)Cs in the lichen species was found in Lepraria incana and Xanthoria parietina, 30.2, 9.8 Bq/kg respectively, and lowest average accumulation capacity were found in Ramalina farinacea 2.7 Bq/kg (dry weight). This study showed that activity concentration (137)Cs is in crustose > foliose > fruticose lichens in the same biotope. Thus, crustose lichens are capable to accumulate higher (137)Cs than foliose and fruticose species because of different factors such as special morphological characteristics in these species and large surface/volume ratio or longer biological half-life of (137)Cs in lichen Lepraria incana. Therefore, Lepraria incana due to high concentration capability of (137)Cs (approximately 3 and 11 time higher than Xanthoria parietina and Ramalina farinacea, respectively), is introduced as biomonitor of Cesium-137 from Ramsar, North of Iran.

  10. Selecting and applying cesium-137 conversion models to estimate soil erosion rates in cultivated fields.

    Science.gov (United States)

    Li, Sheng; Lobb, David A; Tiessen, Kevin H D; McConkey, Brian G

    2010-01-01

    The fallout radionuclide cesium-137 ((137)Cs) has been successfully used in soil erosion studies worldwide. However, discrepancies often exist between the erosion rates estimated using various conversion models. As a result, there is often confusion in the use of the various models and in the interpretation of the data. Therefore, the objective of this study was to test the structural and parametrical uncertainties associated with four conversion models typically used in cultivated agricultural landscapes. For the structural uncertainties, the Soil Constituent Redistribution by Erosion Model (SCREM) was developed and used to simulate the redistribution of fallout (137)Cs due to tillage and water erosion along a simple two-dimensional (horizontal and vertical) transect. The SCREM-predicted (137)Cs inventories were then imported into the conversion models to estimate the erosion rates. The structural uncertainties of the conversion models were assessed based on the comparisons between the conversion-model-estimated erosion rates and the erosion rates determined or used in the SCREM. For the parametrical uncertainties, test runs were conducted by varying the values of the parameters used in the model, and the parametrical uncertainties were assessed based on the responsive changes of the estimated erosion rates. Our results suggest that: (i) the performance/accuracy of the conversion models was largely dependent on the relative contributions of water vs. tillage erosion; and (ii) the estimated erosion rates were highly sensitive to the input values of the reference (137)Cs level, particle size correction factors and tillage depth. Guidelines were proposed to aid researchers in selecting and applying the conversion models under various situations common to agricultural landscapes.

  11. An Integrated Hydrologic Modeling Approach to Cesium-137 Transport in Forested Fukushima Watersheds

    Science.gov (United States)

    Siirila-Woodburn, E. R.; Steefel, C. I.; Williams, K. H.; Birkholzer, J. T.

    2015-12-01

    The 2011 Fukushima Daiichi Nuclear Power Plant (FDNPP) accident in Japan resulted in a significant dissemination of cesium-137 (Cs-137) over a wide area west of the plant, including the contamination of many watersheds and the subsequent evacuation of many communities. Today approximately 90% of on-land Cs-137 fallout following the accident resides in the upper 5 cm of forest soils. While this can be partially attributed to the forested composition of the prefecture (70%), there is also difficulty in cleanup efforts in these regions due to a lack of understanding and predictive capability of radioisotopes transport at the catchment to watershed scale. Subsequently, there is an uncertain, but likely long-term impact on local communities with implications for the use of nuclear energy use worldwide. Due to the complex nature of forest eco-hydrology, sophisticated modeling tools to accurately predict Cs-137 fluxes across different spatial and temporal scales are required. High fidelity, high resolution numerical modeling techniques in conjunction with parallel high performance computing is required to accurately determine transport and feedbacks in these complex systems. To better understand the fundamental transport of Cs-137, a watershed near the FDNPP is modeled with an integrated hydrologic model that includes variably saturated groundwater and overland flow in addition to atmospheric and vegetative processes via a coupled land surface model. Of specific interest is the impact of land cover type on hydrologic flow in the area, which will likely play an important role in erosion patterns and the consequent transport of Cs-137 strongly sorbed to surface soils. Risk management practices (for example, passive remediation versus active remediation such as targeted logging) for two principal tree types (evergreen and deciduous) are informed given the simulated responses to flow patterns assuming different quantities and spatial distribution patterns of each tree type.

  12. The Transfer and diffusion of Cesium 137 within forest ecosystem in Fukushima after the nuclear power plant accident

    Energy Technology Data Exchange (ETDEWEB)

    Suzuki, Takahiro; Murakami, Masashi [Community Ecology Lab., Biology Course, Faculty of Science, Chiba University, Chiba, 263-8522 (Japan); Ishii, Nobuyoshi [National Institute of Radiological Sciences, Chiba, 263-8555 (Japan); Tanoi, Keitaro; Hirose, Atsushi; Ohte, Nobuhito [Graduate School of Agricultural and Life Sciences, The University of Tokyo, Tokyo, 113-8657 (Japan)

    2014-07-01

    A large amount of radionuclides was released from the Fukushima Daiichi Nuclear Power Plant (FDNPP) accident after the disastrous earthquake and subsequent tsunami of March 2011. Among the variety of radionuclides released from FDNPP, cesium 137 ({sup 137}Cs) is the most worrying radionuclide in the environment, with a half-life of 30 years. Since most of the Japanese land area is covered by forest, the distribution and transportation of radioactive materials within forest ecosystems should be conscientiously monitored. In Europe, many studies reported that the {sup 137}Cs deposition caused by the Chernobyl accident has still been distributed in the litter and soil layers and has become a source for the soil-to-plant transfer. Most of these studies emphasize the 'stability' of {sup 137}Cs within forest ecosystems, because {sup 137}Cs are considered to be strongly and immediately fixed in clay minerals. Even though there are many studies of the soil-to-plant transfer of {sup 137}Cs in forest after several years of Chernobyl accident, very initial distribution and transfer of {sup 137}Cs in food web within one to two years after the deposition in forest ecosystems have never been examined. The evaluation of the initial dynamics of {sup 137}Cs in forest ecosystems should be quite important because of the increasing stability of {sup 137}Cs after the deposition. The accumulation and transfer of {sup 137}Cs through food web within forest ecosystems were examined by collecting various organisms at forests in Fukushima. The {sup 137}Cs concentrations, natural Cs and K concentrations, and delta {sup 15}N of the specimens were measured to evaluate the occurrence of bioaccumulation or bio-diffusion of {sup 137}Cs through tropic interaction within forest ecosystem. {sup 137}Cs was highly concentrated on leaf litters which had been deposited in autumn 2010, before the accident. This accumulated {sup 137}Cs had transferred to higher trophic organisms mainly through

  13. The burden of cesium 137 in forest clerks; Die Belastung mit Caesium 137 bei Beschaeftigten der Forstverwaltung

    Energy Technology Data Exchange (ETDEWEB)

    Piechotowski, I.; Jaroni, J. [Landesgesundheitsamt Baden-Wuerttemberg, Stuttgart (Germany); Link, B. [Arbeits- und Sozialministerium des Landes Baden-Wuerttemberg, Stuttgart (Germany); Groezinger, O. [Ministerium fuer Umwelt und Verkehr des Landes Baden-Wuerttemberg, Stuttgart (Germany)

    2000-07-01

    In 47 forest clerks from the regions Ortenau and Oberschwaben in south-west Germany the incorporation of cesium 137 and potassium 40 was measured in autumn 1994. Soil burden as well as burden of nutrition with cesium 137 are different in these regions for geological reasons and as a result of the nuclear accident of Chernobyl. Caused by low content of clay in Oberschwaben, the transfer of cesium to plants is assisted. Heavy rainfall after the nuclear accident led to an additional increase of burden. The median of the concentration of cesium 137 was 1.4 Bq/kg body weight. The median for potassium 40 was 58 Bq/kg body weight. For cesium 137 regional differences were observed. For persons from Oberschwaben the median for cesium 137 was with 2.8 Bq/kg body weight clearly higher than for persons from Ortenau with 0,6 Bq/kg body weight. Concerning nutrition habits, the clearest difference was found comparing persons who had ate a minimum of four portions of deer from the surroundings within the last four weeks with persons who had ate less than four portions of deer from the surroundings within the last four weeks. The difference was greater in Oberschwaben than in Ortenau. The effective dose of cesium 137 calculated on the basis of the incorporation is very low compared to natural radiation. This is also valid for persons from Oberschwaben. (orig.) [German] Im Herbst 1994 wurde bei insgesamt 47 Bediensteten der Forstverwaltung aus den Regionen Ortenaukreis und Oberschwaben die Inkorportation an Caesium 137 und Kalium 40 gemessen. Sowohl die Bodenbelastung als auch die Belastung von Nahrungsmitteln mit Caesium 137 unterscheiden sich in diesen Gebieten bedingt durch geologische Besonderheiten und in Folge des Reaktorunfalls von Tschernobyl. Aufgrund eines geringen Anteils an Tonerden wird in Oberschwaben der Caesiumtransfer in Pflanzen beguenstigt, eine zusaetzliche Erhoehung der Belastung erfolgte durch starke Niederschlaege nach dem Reaktorunfall. Die Konzentration fuer

  14. Assessing relationships between forest structure and soil erosion in mountainous forest using a Cesium-137 tracer technique

    Science.gov (United States)

    Choi, Kwanghun; Reineking, Björn

    2016-04-01

    The fallout radionuclides (FRNs) particularly Cesium-137 are known as a quantitatively reliable means of estimating sediment redistribution rates within agricultural landscapes and forested area. However, fewer studies have done using FRNs in forested areas even though understanding soil redistribution patterns in mountainous forest areas is one of the important issues for forest management. The objective of this study is to figure out key forest structures affecting soil redistribution rate. In this study, we estimated soil loss and gain rate at 50 points with various forest types and topography in steep mountainous forest area in the Experimental Forest of Kangwon National University in Kangwon Province, South Korea by the Cesium-137 tracing technique. The results show the factors related to the topography such as slope and water accumulation have little effect on soil redistribution rate. The shrub and small tree layer affect more on soil redistribution rate. Additionally, the data shows relatively higher erosion rate in Korean Pine tree plantation area (Pinus koraiensis Sieb. et Zucc.) than semi-natural deciduous and Quercus forests where shrubs and small trees are more prevalent.

  15. Preparation and characterization of cesium-137 aluminosilicate pellets for radioactive source applications

    Energy Technology Data Exchange (ETDEWEB)

    Schultz, F.J.; Tompkins, J.A.; Haff, K.W.; Case, F.N.

    1981-07-01

    Twenty-seven fully loaded /sup 137/Cs aluminosilicate pellets were fabricated in a hot cell by the vacuum hot pressing of a cesium carbonate/montmorillonite clay mixture at 1500/sup 0/C and 570 psig. Four pellets were selected for characterization studies which included calorimetric measurements, metallography, scanning electron microscope and electron backscattering (SEM-BSE), electron microprobe, x-ray diffraction, and cesium ion leachability measurements. Each test pellet contained 437 to 450 curies of /sup 137/Cs as determined by calorimetric measurements. Metallographic examinations revealed a two-phase system: a primary, granular, gray matrix phase containing large and small pores and small pore agglomerations, and a secondary fused phase interspersed throughout the gray matrix. SEM-BSE analyses showed that cesium and silicon were uniformly distributed throughout both phases of the pellet. This indicated that the cesium-silicon-clay reaction went to completion. Aluminum homogeneity was unconfirmed due to the high background noise associated with the inherent radioactivity of the test specimens. X-ray diffraction analyses of both radioactive and non-radioactive aluminosilicate pellets confirmed the crystal lattice structure to be pollucite. Cesium ion quasistatic leachability measurements determined the leach rates of fully loaded /sup 137/Cs sectioned pollucite pellets to date to be 4.61 to 34.4 x 10/sup -10/ kg m/sup -2/s/sup -1/, while static leach tests performed on unsectioned fully loaded pellets showed the leach rates of the cesium ion to date to be 2.25 to 3.41 x 10/sup -12/ kg m/sup -2/s/sup -1/. The cesium ion diffusion coefficients through the pollucite pellet were calculated using Fick's first and second laws of diffusion. The diffusion coefficients calculated for three tracer level /sup 137/Cs aluminosilicate pellets were 1.29 x 10/sup -16/m/sup 2/s/sup -1/, 6.88 x 10/sup -17/m/sup 2/s/sup -1/, and 1.35 x 10/sup -17/m/sup 2/s/sup -1/, respectively.

  16. Predicting Sediment and Cesium-137 Transported to Offsite During Extreme Floods

    Energy Technology Data Exchange (ETDEWEB)

    Bao, Y.

    1999-04-12

    This paper presents the methods and results of a research project for predicting contaminated sediment transport from Oak Ridge Reservation to offside under potential extreme flood conditions. A computer model, Hydrologic Simulation Program--FORTRANE (HSPF), was calibrated and validated for White Oak Creek watershed using a five-year data. The model was then used to quantify the effects of a potential 100-year flood event in terms of the sediment transport and {sup 137}Cs movement. Results from computer simulation showed that during a 100-year flood event the watershed and channel bed became the major sources of the {sup 137}Cs. A 100-year flood event may result in 3.2 Ci of the total annual release of {sup 137}Cs which is six times of the averaged annual release observed during a five-year time period.

  17. Identification of environmentally derived cesium-137 burdens in a worker population

    Energy Technology Data Exchange (ETDEWEB)

    MacLellan, J.A.; Lynch, T.P.; Rieksts, G.A.; Brodzinski, R.L.

    1993-01-01

    During 1990, whole body measurements of a number of workers with little probability of onsite occupational exposure showed positive evidence of {sup 137}Cs. Further investigation revealed that many of these workers supplemented their diet with a significant portion of wild game, mainly deer and elk. To validate the assumption of an environmental source, donated samples of venison and other game were analyzed by gamma spectroscopy. Results ranged from less than 0.1 to almost 100 Bq kg{sup {minus}l} (0.003 to 2.7 nCi kg{sup {minus}1}) and showed a correlation with the habitat from which the game was taken. Venison samples obtained from the two workers with the highest body burdens showed the highest activity. A questionnaire is now used to identify workers with an elevated potential for environmental-intakes.

  18. Identification of environmentally derived cesium-137 burdens in a worker population

    Energy Technology Data Exchange (ETDEWEB)

    MacLellan, J.A.; Lynch, T.P.; Rieksts, G.A.; Brodzinski, R.L.

    1993-01-01

    During 1990, whole body measurements of a number of workers with little probability of onsite occupational exposure showed positive evidence of [sup 137]Cs. Further investigation revealed that many of these workers supplemented their diet with a significant portion of wild game, mainly deer and elk. To validate the assumption of an environmental source, donated samples of venison and other game were analyzed by gamma spectroscopy. Results ranged from less than 0.1 to almost 100 Bq kg[sup [minus]l] (0.003 to 2.7 nCi kg[sup [minus]1]) and showed a correlation with the habitat from which the game was taken. Venison samples obtained from the two workers with the highest body burdens showed the highest activity. A questionnaire is now used to identify workers with an elevated potential for environmental-intakes.

  19. Contribution of Asian dust to atmospheric deposition of radioactive cesium ((137)Cs).

    Science.gov (United States)

    Fukuyama, Taijiro; Fujiwara, Hideshi

    2008-11-01

    Both Asian dust (kosa) transported from the East Asian continent and locally suspended dust near monitoring sites contribute to the observed atmospheric deposition of (137)Cs in Japan. To estimate the relative contribution of these dust phenomena to the total (137)Cs deposition, we monitored weekly deposition of mineral particles and (137)Cs in spring. Deposition of (137)Cs from a single Asian dust event was 62.3 mBq m(-2) and accounted for 67% of the total (137)Cs deposition during the entire monitoring period. Furthermore, we found high (137)Cs specific activity in the Asian dust deposition sample. Although local dust events contributed to (137)Cs deposition, their contribution was considerably smaller than that of Asian dust. We conclude that the primary source of atmospheric (137)Cs in Japan is dust transported from the East Asian continent.

  20. Individual Radiological Protection Monitoring of Utrok Atoll Residents Based on Whole Body Counting of Cesium-137 (137Cs) and Plutonium Bioassay

    Energy Technology Data Exchange (ETDEWEB)

    Hamilton, T; Kehl, S; Brown, T; Martinelli, R; Hickman, D; Jue, T; Tumey, S; Langston, R

    2007-06-08

    This report contains individual radiological protection surveillance data developed during 2006 for adult members of a select group of families living on Utrok Atoll. These Group I volunteers all underwent a whole-body count to determine levels of internally deposited cesium-137 ({sup 137}Cs) and supplied a bioassay sample for analysis of plutonium isotopes. Measurement data were obtained and the results compared with an equivalent set of measurement data for {sup 137}Cs and plutonium isotopes from a second group of adult volunteers (Group II) who were long-term residents of Utrok Atoll. For the purposes of this comparison, Group II volunteers were considered representative of the general population on Utrok Atoll. The general aim of the study was to determine residual systemic burdens of fallout radionuclides in each volunteer group, develop data in response to addressing some specific concerns about the preferential uptake and potential health consequences of residual fallout radionuclides in Group I volunteers, and generally provide some perspective on the significance of radiation doses delivered to volunteers (and the general Utrok Atoll resident population) in terms of radiological protection standards and health risks. Based on dose estimates from measurements of internally deposited {sup 137}Cs and plutonium isotopes, the data and information developed in this report clearly show that neither volunteer group has acquired levels of internally deposited fallout radionuclides specific to nuclear weapons testing in the Marshall Islands that are likely to have any consequence on human health. Moreover, the dose estimates are well below radiological protection standards as prescribed by U.S. regulators and international agencies, and are very small when compared to doses from natural sources of radiation in the Marshall Islands and the threshold where radiation health effects could be either medically diagnosed in an individual or epidemiologically discerned in a

  1. Germline mutations in people descendants occupationally exposed to ionizing radiation from Cesium 137; Mutacoes germinativas na prole de pessoas expostas ocupacionalmente a radiacao ionizante de Cesio 137

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Juliana Ferreira da

    2016-07-01

    The radiological accident in Goiania in 1987, resulted in a serious episode of human contamination, animal, plant and environmental were exposed to Cesium 137 chloride ({sup 137}CsCl) that caused contamination and accidental and occupational exposure to ionizing radiation. Ionizing radiation is one of the environmental components that causes most cellular stress in complex organisms. Exposure to ionizing radiation induces breaks in nucleic acids, especially, DNA double and single strand breaks. Chromosomal microarray analysis is an important tool for the detection and microdeletion and microduplications in the genomes. In this study we proposed to analyze the effect of exposure to RI on the formation of CNVs in an exposed human population occupationally to ionizing radiation from Cesium 137 during the accident in Goiania. The exposed group consisted of 07 families, of which at least one parent was occupationally exposed to ionizing radiation from Cesium 137, including a total of 25 individuals, do not know the absorbed dose of the military who were occupationally exposed to ionizing radiation. 11 families with a group of individuals not exposed to IR was used as control were used including a total of 33 individuals with no history of exposure to RI. The genotyping microarray was conducted in CytoScan HD system (Affymetrix®) without then analyzes was performed in ChAS® software. The statistical tests used were: Shapiro-Wilk, Mann- Whitney U, Spearman correlation, discriminant function analysis, binomial test, χ{sup 2} test. All analyzes were performed using the statistical package SPSS 21.0, with a significance level of 5% (p <0.05). The frequency of CNVs were estimated loss / generation, gain / generation and burden / generation, representing 3,9 x 10{sup -5}, 6,8 x 10{sup -6} and 4,6 x 10{sup -5} respectively for the exposed group. For the control group, the frequencies were 2,1 x 10{sup -5}, 5,9 x 10{sup -6} and 3,1 x 10{sup -5} respectively. Thus, the

  2. Cesium-137 global fallout into the Ob river basin and its influence on the Kara sea contamination - Weapons fallout cesium-137 in the Ob' catchment landscapes and its influence on radioactive contamination of the Kara sea: Western Siberia, Russia

    Energy Technology Data Exchange (ETDEWEB)

    Semenkov, Ivan N.; Miroshnikov, Alexey Yu. [The Organization of Russian Academy of Sciences Institute of geology of ore deposits, petrography, mineralogy and geochemistry Russian Academy of Sciences (Russian Federation)

    2014-07-01

    or acid soils with considerable among of dissolve organic matter. And {sup 137}Cs accumulates in slightly alkaline soils with mull in topsoil. The data obtained show that global fallout cesium-137 runoff from undisturbing humid first-order river basins (n=1) is less than 0.5 Ci*km{sup -1}. Runoff from arable semi-humid first-order river basins (n=2) varies from 3 to 35 Ci*km{sup -1}. According to GIS, internal flow areas occur 23% of the Ob' river basin total area and accumulate whole {sup 137}Cs. Humid and semi-humid river basins cover 40% and 8% of study area, respectively. We assume these basins yield as the main contribution in {sup 137}Cs runoff from the Ob' river basin. Thus global fallout caesium-137 runoff is 0.9-6.1 kCi including radioactive decay (0.5-3.4% of total storage) from the Ob' river basin to the Kara sea. Comparable among of caesium-137 could enter to the Kara sea due to liquid radioactive wastes by the nuclear plants located in the Ob' and the Enisey river basins. As a result, global fallout caesium-137 runoff from the background landscapes of the Ob' and the Enisey river basins plays an important role in radioactive contamination of the Kara sea. Conducted research results proved to estimate yield of radiochemical plants to radioactive contamination of the Arctic Ocean. (authors)

  3. Seasonal concentrations of cesium-137 in rumen content, skeletal muscles and feces of caribou from the Porcupine herd: lichen ingestion rates and implications for human consumption

    Directory of Open Access Journals (Sweden)

    A. C. Allaye-Chan

    1990-09-01

    Full Text Available The Porcupine caribou herd was monitored for cesium-137 during 1987 to address human health concerns over potential meat contamination by radioactive fallout from the Chernobyl accident, and to determine lichen intake rates based on body burdens of radiocesium. A total of 36 caribou were collected from northwestern Alaska and the Yukon Territories in March, June, September, and November. Mean radiocesium concentrations in skeletal muscle peaked in March at 133 Bq/kg fresh weight. This value should not prove hazardous to human health. Radiocesium concentrations in skeletal muscle (wet weight ranged from approximately 22 to 50% of radiocesium concentrations in rumen contents (dry weight, and from approximately 15 to 37% of radiocesium concentrations in feces (dry weight. Radioactivity in feces was significantly correlated with radioactivity in rumen contents. Computer simulations relating lichen intake rates to radiocesium body burdens are presented for 3 scenarios: (1 when seasonal intakes were adjusted to provide the optimum fit between simulated and observed radiocesium body burdens (2 when seasonal intakes were based on empirical data, and (3 when seasonal intakes were adjusted to yield a "conventional" radiocesium curve of a slow fall build-up prior to a late winter plateau.

  4. Size Effects of Gold and Iron Nanoparticles on Radiation Dose Enhancement in Brachytherapy and Teletherapy: A Monte Carlo Study

    Directory of Open Access Journals (Sweden)

    Ahad Ollah Ezzati

    2014-08-01

    Full Text Available Introduction In this study, we aimed to calculate dose enhancement factor (DEF for gold (Au and iron (Fe nanoparticles (NPs in brachytherapy and teletherapy, using Monte Carlo (MC method. Materials and Methods In this study, a new algorithm was introduced to calculate dose enhancement by AuNPs and FeNPs for Iridium-192 (Ir-192 brachytherapy and Cobalt-60 (Co-60 teletherapy sources, using the MC method. In this algorithm, the semi-random distribution of NPs was used instead of the regular distribution. Diameters were assumed to be 15, 30, and 100 nm in brachytherapy and 15 and 30 nm in teletherapy. Monte Carlo MCNP4C code was used for simulations, and NP density values were 0.107 mg/ml and 0.112 mg/ml in brachytherapy and teletherapy, respectively. Results AuNPs significantly enhanced the radiation dose in brachytherapy (approximately 60%, and 100 nm diameter NPs showed the most uniform dose distribution. AuNPs had an insignificant effect on teletherapy radiation field, with a dose enhancement ratio of 3% (about the calculation uncertainty or less. In addition, FeNPs had an insignificant effect on both brachytherapy and teletherapy radiation fields. FeNPs dose enhancement was 3% in brachytherapy and 6% (about the calculation uncertainty or less in teletherapy. Conclusion It can be concluded that AuNPs can significantly increase the absorbed dose in brachytherapy; however, FeNPs do not have a noticeable effect on the absorbed dose

  5. Cytogenetic evaluation of persons exposed to Cesium-137 radiation accident in Goiania (Brazil); Avaliacao citogenetica de individuos expostos acidentalmente a radiacao ionizante de Cesio-137 em Goiania (Brasil)

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Claudio Carlos da

    2000-07-01

    This dissertation describes a cytogenetic evaluation of individuals exposed to cesium-137 gamma radiation during the radioactive accident of Goiania in 1987. The study group is comprised of 14 individuals who had absorbed doses varying from 1 to 7 Gy. In order to obtain metaphase spreads,peripheral blood collected from exposed individuals 1-1,5 year after ionizing radiation exposure, was cultured following basic protocols for PHA-Lymphocyte stimulation. Individual slides were kept for 12 years at room temperature and in the dark. A control group of unexposed individuals was chosen from the Goiania population. Both groups donated blood voluntarily and the unexposed population had no history of exposure to genotoxic agents. The ordinary methodology, consisting of staining chromosomes with Giemsa 4%, was used to determine the biological half-life of unstable chromosomes aberrations. Using Buckston's model (1967) we predicted the half-life of T-cells carrying unstable chromosome aberrations to be between 204-312 days, which is in agreement with the results of Ramalho (1993) who reported a half-life of 140 days a similar for population. Additionally, we used fluorescence in situ hybridization (FISH) as the chosen method to evaluate 12-year old metaphase spreads. To date, we have no knowledge of the use of FISH methodology applied to samples as old as our. Prior to hybridization, chromosomes showed intense dehydration and signs of severe degradation. A pretreatment of aged slides in Carnoy's fixative for 16 hours, followed by exposing the slides to water vapour at 60 deg C for 4 hours improved the fluorescent signal of whole chromosomes probes, making it possible to evaluate old metaphase spreads. Our results suggest that is possible to validate FISH as a viable tool for retrospective biodosimetric studies, even in those cases when chromosome preparations were dehydrated and showed signs of chromosome degradation. (author)

  6. 76 FR 44378 - Policy Statement of the U.S. Nuclear Regulatory Commission on the Protection of Cesium-137...

    Science.gov (United States)

    2011-07-25

    ... of instrumentation and dosimetry, especially for critical reactor and first responder equipment. The... Commission encourages research to develop alternative chemical forms for large activity Cs-137 sources. Given... working with its domestic and international partners to assess, integrate, and improve its...

  7. Non cancerous diseases following a chronic intern contamination by caesium 137: cataracts and cardiac arrhythmias; Pathologies non cancereuses potentiellement consecutives a une contamination interne chronique par le cesium 137: cataractes et arythmies cardiaques

    Energy Technology Data Exchange (ETDEWEB)

    Landon, G

    2008-07-15

    This work of thesis joins within the framework of an analysis of the sanitary consequences of the nuclear accident of Chernobylsk. Since 2005, the I.R.S.N. is interested in the not cancerous pathologies (cataracts, and cardiac arrhythmias) observed among the children living on the contaminated territories after the fallout of Chernobylsk and has in this aim implemented a research programme called E.P.I.C.E. (Evaluation of the pathologies induced by a chronicle contamination by cesium) whom objective is to show an eventual link between the chronicle ingestion of contaminated food and these pathologies emergence. An exploitation of the results of the pilot study,first phase of the E.P.I.C.E. program was realized. The analysis was completed by two bibliographical reviews relative to the knowledge available on these diseases. The results of this pilot study suggest: on one hand, an absence of link between the activity in cesium 137 at the level of the heart, of the whole body and the emergence of disorder of the heart rhythm; on the other hand, for the cases of cataract, a link between the load in cesium 137 at the neck level and the emergence of the disease in 40 % of the cases. However, these results must be considered with caution because several limits and, in particular, a way of selection affect this study. concerning the scientific literature, this one stays rather poor because only thee articles make reference to a relationship between cesium 137 and the emergence of these non cancerous pathologies. After having exposed the context, this thesis draws up the situation of knowledge relative to cataracts and to cardiac arrhythmias and their possible relationship with ionizing radiations, collect the results stemming from the analysis of the pilot study and envisages future epidemiological studies. (N.C.)

  8. 137 CS content in coconut water and copra in French Polynesia: contribution to the dose for population; Le cesium 137 dans la noix de coco en polynesie francaise : contribution a l'exposition de la population

    Energy Technology Data Exchange (ETDEWEB)

    Poletiko, C.; Arnould, C.; Sarbach, J. [Laboratoire d' etude et de surveillance de l' environnement, Papeete, Polynesie francaise, Tahiti (France); Bablet, J.P.; Ducousso, R. [Service mixte de controle biologique, Monthlery cedex (France)

    1992-07-01

    Coconut tree has the peculiarity to be a good integrator for alkaline metals. The isotope 137 of cesium, which was generated during previous atmospheric nuclear tests, has a high fission yield and a half-life of about 30 years; this nuclide is supposed to be still present in food chain in French Polynesia. In this food chain coconut water and coconut copra are ingested depending upon diet customs and areas of French Polynesia. For some islands, among local foodstuffs, cesium 137 content in coconut highly contributes to the dose. Spectrometry gamma results and annual doses calculation since 1966 are displayed. (author)

  9. Human factors evaluation of teletherapy: Function and task analysis. Volume 2

    Energy Technology Data Exchange (ETDEWEB)

    Kaye, R.D.; Henriksen, K.; Jones, R. [Hughes Training, Inc., Falls Church, VA (United States); Morisseau, D.S.; Serig, D.I. [Nuclear Regulatory Commission, Washington, DC (United States). Div. of Systems Technology

    1995-07-01

    As a treatment methodology, teletherapy selectively destroys cancerous and other tissue by exposure to an external beam of ionizing radiation. Sources of radiation are either a radioactive isotope, typically Cobalt-60 (Co-60), or a linear accelerator. Records maintained by the NRC have identified instances of teletherapy misadministration where the delivered radiation dose has differed from the radiation prescription (e.g., instances where fractions were delivered to the wrong patient, to the wrong body part, or were too great or too little with respect to the defined treatment volume). Both human error and machine malfunction have led to misadministrations. Effective and safe treatment requires a concern for precision and consistency of human-human and human-machine interactions throughout the course of therapy. The present study is the first part of a series of human factors evaluations for identifying the root causes that lead to human error in the teletherapy environment. The human factors evaluations included: (1) a function and task analysis of teletherapy activities, (2) an evaluation of the human-system interfaces, (3) an evaluation of procedures used by teletherapy staff, (4) an evaluation of the training and qualifications of treatment staff (excluding the oncologists), (5) an evaluation of organizational practices and policies, and (6) an identification of problems and alternative approaches for NRC and industry attention. The present report addresses the function and task analysis of teletherapy activities and provides the foundation for the conduct of the subsequent evaluations. The report includes sections on background, methodology, a description of the function and task analysis, and use of the task analysis findings for the subsequent tasks. The function and task analysis data base also is included.

  10. Phenomenological and analytical interpretation of the rain-deposit relationship used for the reconstitution of the cesium 137 deposit in France consecutive to the accident of Chernobylsk; Interpretation phenomenologique et analytique de la relation pluie-depot utilisee pour la reconstitution des depots de {sup 137}Cs en France consecutifs a l'accident de Tchernobyl

    Energy Technology Data Exchange (ETDEWEB)

    Champion, D.; Renaud, Ph.; Metivier, J.M.; Garcia-Sanchez, L.; Pourcelot, L. [Institut de Radioprotection et de Surete Nucleaire, Dir. de l' environnement et de l' intervention 92 - Fontenay-aux-Roses (France)

    2005-11-15

    The works presented in this report allow to give two conclusions: the first one bears on the reconstitution of the cesium 137 deposits induced by the Chernobylsk accident; the second one bears on the methods improvement of post accident consequences evaluation induced by the radioactive atmosphere fallout. (N.C.)

  11. Estimation of Radiation Doses in the Marshall Islands Based on Whole Body Counting of Cesium-137 (137Cs) and Plutonium Urinalysis

    Energy Technology Data Exchange (ETDEWEB)

    Daniels, J; Hickman, D; Kehl, S; Hamilton, T

    2007-06-11

    Under the auspices of the U.S. Department of Energy (USDOE), researchers from the Lawrence Livermore National Laboratory (LLNL) have recently implemented a series of initiatives to address long-term radiological surveillance needs at former nuclear test sites in the Republic of the Marshall Islands (RMI). The aim of this radiological surveillance monitoring program (RSMP) is to provide timely radiation protection for individuals in the Marshall Islands with respect to two of the most important internally deposited fallout radionuclides-cesium-137 ({sup 137}Cs) and long-lived isotopes 239 and 240 of plutonium ({sup 239+240}Pu) (Robison et al., 1997 and references therein). Therefore, whole-body counting for {sup 137}Cs and a sensitive bioassay for the presence of {sup 239+240}Pu excreted in urine were adopted as the two most applicable in vivo analytical methods to assess radiation doses for individuals in the RMI from internally deposited fallout radionuclides (see Hamilton et al., 2006a-c; Bell et al., 2002). Through 2005, the USDOE has established three permanent whole-body counting facilities in the Marshall Islands: the Enewetak Radiological Laboratory on Enewetak Atoll, the Utrok Whole-Body Counting Facility on Majuro Atoll, and the Rongelap Whole-Body Counting Facility on Rongelap Atoll. These whole-body counting facilities are operated and maintained by trained Marshallese technicians. Scientists from LLNL provide the technical support and training necessary for maintaining quality assurance for data acquisition and dose reporting. This technical basis document summarizes the methodologies used to calculate the annual total effective dose equivalent (TEDE; or dose for the calendar year of measurement) based on whole-body counting of internally deposited {sup 137}Cs and the measurement of {sup 239+240}Pu excreted in urine. Whole-body counting provides a direct measure of the total amount (or burden) of {sup 137}Cs present in the human body at the time of

  12. Estimation of Radiation Doses in the Marshall Islands Based on Whole Body Counting of Cesium-137 (137Cs) and Plutonium Urinalysis

    Energy Technology Data Exchange (ETDEWEB)

    Daniels, J; Hickman, D; Kehl, S; Hamilton, T

    2007-06-11

    Under the auspices of the U.S. Department of Energy (USDOE), researchers from the Lawrence Livermore National Laboratory (LLNL) have recently implemented a series of initiatives to address long-term radiological surveillance needs at former nuclear test sites in the Republic of the Marshall Islands (RMI). The aim of this radiological surveillance monitoring program (RSMP) is to provide timely radiation protection for individuals in the Marshall Islands with respect to two of the most important internally deposited fallout radionuclides-cesium-137 ({sup 137}Cs) and long-lived isotopes 239 and 240 of plutonium ({sup 239+240}Pu) (Robison et al., 1997 and references therein). Therefore, whole-body counting for {sup 137}Cs and a sensitive bioassay for the presence of {sup 239+240}Pu excreted in urine were adopted as the two most applicable in vivo analytical methods to assess radiation doses for individuals in the RMI from internally deposited fallout radionuclides (see Hamilton et al., 2006a-c; Bell et al., 2002). Through 2005, the USDOE has established three permanent whole-body counting facilities in the Marshall Islands: the Enewetak Radiological Laboratory on Enewetak Atoll, the Utrok Whole-Body Counting Facility on Majuro Atoll, and the Rongelap Whole-Body Counting Facility on Rongelap Atoll. These whole-body counting facilities are operated and maintained by trained Marshallese technicians. Scientists from LLNL provide the technical support and training necessary for maintaining quality assurance for data acquisition and dose reporting. This technical basis document summarizes the methodologies used to calculate the annual total effective dose equivalent (TEDE; or dose for the calendar year of measurement) based on whole-body counting of internally deposited {sup 137}Cs and the measurement of {sup 239+240}Pu excreted in urine. Whole-body counting provides a direct measure of the total amount (or burden) of {sup 137}Cs present in the human body at the time of

  13. Human factors evaluation of teletherapy: Human-system interfaces and procedures. Volume 3

    Energy Technology Data Exchange (ETDEWEB)

    Kaye, R.D.; Henriksen, K.; Jones, R. [Hughes Training, Inc., Falls Church, VA (United States); Morisseau, D.S.; Serig, D.I. [Nuclear Regulatory Commission, Washington, DC (United States). Div. of Systems Technology

    1995-07-01

    A series of human factors evaluations was undertaken to better understand the contributing factors to human error in the teletherapy environment. Teletherapy is a multidisciplinary methodology for treating cancerous tissue through selective exposure to an external beam of ionizing radiation. The principal sources of radiation are a radioactive isotope, typically cobalt60 (Co-60), or a linear accelerator device capable of producing very high energy x-ray and electron beams. A team of human factors specialists conducted site visits to radiation oncology departments at community hospitals, university centers, and free-standing clinics. In addition, a panel of radiation oncologists, medical physicists, and radiation technologists served as subject matter experts. A function and task analysis was initially performed to guide subsequent evaluations in the areas of user-system interfaces, procedures, training and qualifications, and organizational policies and practices. The present report focuses on an evaluation of the human-system interfaces in relation to the treatment machines and supporting equipment (e.g., simulators, treatment planning computers, control consoles, patient charts) found in the teletherapy environment. The report also evaluates operating, maintenance and emergency procedures and practices involved in teletherapy. The evaluations are based on the function and task analysis and established human engineering guidelines, where applicable.

  14. Oak Ridge Reservation Volume 3. Records relating to RaLa, iodine-131, and cesium-137 at the Oak Ridge National Laboratory and the Oak Ridge Operations Office: A guide to record series of the Department of Energy and its contractors

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-03-21

    The purpose of this guide is to describe each of the documents and record series pertaining to the production, release, and disposal of radioactive barium-lanthanum (RaLa), iodine-131, and cesium-137 at the Department of Energy`s (DOE) Oak Ridge National Laboratory (ORNL) in Oak Ridge, Tennessee. History Associates Incorporated (HAI) prepared this guide as part of DOE`s Epidemiologic Records Inventory Project, which seeks to verify and conduct inventories of epidemiologic and health-related records at various DOE and DOE contractor sites. This introduction briefly describes the Epidemiologic Records Inventory Project and HAI`s role. It provides information on the history of the DOE-Oak Ridge Reservation (ORR), particularly ORNL. Specific attention is given to the production of RaLa and the fission products iodine-131 and cesium-137. This introduction also describes the methodologies HAI used in the selection and inventorying of documents and record series pertaining to RaLa, iodine-131, and cesium-137, and in the production of this guide. Concluding paragraphs describe the arrangement of the record series, explain the information contained in the record series descriptions, and indicate restrictions on access to the records.

  15. The blue drama: narratives of the victim's suffering of Cesium-137 radiological event; O drama azul: narrativas sobre o sofrimento das vitimas do evento radiologico do Cesio-137

    Energy Technology Data Exchange (ETDEWEB)

    Vieira, Suzane de Alencar

    2014-07-01

    This research presents a dramatic approach to the Cesium-137 Radiological Event. The event, which started on Goiania in 1987, did not stop with the end of radiological contamination and continues in a judicial, scientific and narrative process of identification and recognition of new victims. The ethnography’s output follows a theoretical experiment with the notions of drama and event. In order to better understand the pattern of this event, I analyzed narratives such as romances, arts, photographs, news, documentaries, films, academic bibliography and stories that emerged from the research field. I argue that the narratives politicize the discourses of victimization and the suffering experience. The dramatic form of narratives and symbols concentrates on emotions and promotes the emotional commitment of the subjects on the trial. The drama articulates the relationship between the narratives and the event and creates a tactful space that arouses the recognition of victims through the narrative form and the suffering language. The drama occupies a central place on the dynamics of radiological event, as it extends its limits, inflects its intensity and updates the event. As a narrative of the event, the ethnography incorporates and brings up to date the drama as an analysis landmark and the description of the theme as it is absorbed by a dramatic process. (author)

  16. Radiometric evaluation of graves of victims of the accident with Cesium 137 in Goiania, GO, Brazil: 25 years after; Avaliacao radiometrica das sepulturas das vitimas do acidente com o Cesio 137 em Goiania: 25 anos apos

    Energy Technology Data Exchange (ETDEWEB)

    Lage, Leonardo B.; Correa, Rosangela da S.; Santos, Eliane E. dos, E-mail: leonardobl@cnen.gov.br, E-mail: rcorrea@cnen.gov.br, E-mail: esantos@cnen.gov.br [Centro Regional de Ciencias Nucleares do Centro-Oeste (CRCN-CO/CNEN-GO), Abadia de Goias, GO (Brazil); Freitas-Junior, Ruffo, E-mail: uffojr@terra.com.br [Universidade Federal de Goias (UFG), Goiania, GO (Brazil). Faculdade de Medicina. Programa de Mastologia

    2013-07-01

    Twenty-five years after the radiation accident in Goiania, this study aims to evaluate the radiological situation in the area demarcated by the graves of the victims of the accident with cesium-137. Radiometric survey was carried out on the surface that encompasses the four graves and vicinity, from a pre-established mesh. Dose rate measurements were carried out, using the IdentFINDER equipment, positioned at 1 m height from the ground. The values of dose rates at the points measured ranged from 0.03 to 0.07 μSv/h. This variation of dose rate is less than those obtained in the local graveyard and are in the range of background radiation observed in Goiania. Considering the results obtained 25 years after the accident, it was concluded that engineering barriers adopted at that time are effective, stating the place absolutely safe from a radiological point of view, both for the individual from the public as to the environment.

  17. Human factors evaluation of teletherapy: Identification of problems and alternative approaches. Volume 1

    Energy Technology Data Exchange (ETDEWEB)

    Henriksen, K.; Kaye, R.D.; Jones, R. [Hughes Training, Inc., Falls Church, VA (United States); Morisseau, D.S.; Serig, D.I. [Nuclear Regulatory Commission, Washington, DC (United States). Div. of Systems Technology

    1995-07-01

    A series of human factors evaluations was undertaken to better understand the contributing factors to human error in the teletherapy environment. Teletherapy is a multi-disciplinary methodology for treating cancerous tissue through selective exposure to an external beam of ionizing radiation. The principal sources of radiation are a radioactive isotope, typically cobalt60 (Co-60), or a linear accelerator device capable of producing very high energy x-ray and electron beams. A team of human factors specialists, assisted by a panel of radiation oncologists, medical physicists, and radiation technologists, conducted site visits to radiation oncology departments at community hospitals, university centers, and free-standing clinics. A function and task analysis was initially performed to guide subsequent evaluations in the areas of user-system interfaces, procedures, training and qualifications, and organizational policies and practices. The final phase of the project focused on identification of the most significant human factors problems with respect to safe and effective operation of the teletherapy system and an identification and assessment of alternative approaches for resolving the problems. This report presents the findings of this final phase.

  18. The determination of Fukushima-derived cesium-134 and cesium-137 in Japanese green tea samples and their distribution subsequent to simulated beverage preparation.

    Science.gov (United States)

    Cook, Matthew C; Stukel, Matthew J; Zhang, Weihua; Mercier, Jean-Francois; Cooke, Michael W

    2016-03-01

    Health Canada's Radiation Protection Bureau has identified trace quantities of (134)Cs and (137)Cs in commercially available green tea products of Japanese origin. Referenced to March 11, 2011, the activity ratio ((134)Cs/(137)Cs) has been determined to be 1:1, which supports an origin from the Fukushima Dai-ichi Nuclear Power Plant accident. The upper limits of typical tea beverage preparation conditions were applied to the most contaminated of these green tea samples to determine the proportion of radiocesium contamination that would be available for human consumption. The distribution of radiocesium among the components of the extraction experiments (water, residual tea solid, and filter media) was determined by both conventional and Compton-suppressed gamma spectroscopy. The latter aided tremendously in providing a more complete radiocesium distribution profile, particularly for the shorter-lived (134)Cs. Cesium extraction efficiencies of 64 ± 7% and 64 ± 5% were determined based on (134)Cs and (137)Cs, respectively. Annual, effective dose estimates from ingestion of (137)Cs and (134)Cs (1.8-3.7 μSv), arising from the consumption of tea beverages prepared from the most contaminated of these samples, are insignificant relative to both total (∼ 2.4 mSv) and ingested (∼ 0.28 mSv) annual effective doses received from naturally occurring radioactive sources. As such, there is no health concern arising from the consumption of green tea beverages contaminated with radiocesium at the levels encountered in this study.

  19. The technological safety in facilities that manage radioactive sources; La seguridad tecnologica en instalaciones que manejan fuentes radiactivas

    Energy Technology Data Exchange (ETDEWEB)

    Lizcano, D., E-mail: david.lizcano@inin.gob.mx [ININ, Carretera Mexico-Toluca s/n, 52750 Ocoyoacac, Estado de Mexico (Mexico)

    2014-10-15

    The sealed radioactive sources are used inside a wide range of applications in the medicine, industry and investigation around the world. These sources can contain a great radionuclides variety, exhibiting a wide spectrum of activities and radiological half lives. This way, we can find pattern sources of radionuclides as Americium-241, Plutonium-238, Plutonium-239, Thorium-228 and Thorium-230, etc., with some activity of kBq in research laboratories, Iridium-192 and Cesium-137 sources used in brachytherapy with GBq activities, until sources with P Bq activities in industrial irradiators of Cobalt-60 and Cesium-137. This document approach the physical safety that entities like the IAEA recommends for the facilities that contain sealed sources, especially the measures that are taking in the Instituto Nacional de Investigaciones Nucleares (ININ) and others government facilities. (Author)

  20. Distribution of cesium-137 in reindeer

    Directory of Open Access Journals (Sweden)

    Kristina Rissanen

    1990-08-01

    Full Text Available The influence of the Chernobyl accident in 1986 on the Finnish reindeer herding area was much smaller than the effects of the nuclear bomb tests in the 1960s. Only in one small area somewhat more Cs-137 was deposited than in the rest of the reindeer herding area. From that area 20 reindeer were chosen for investigation of the distribution of Cs-137. All tissues, organs, the skeleton, digestive tract, hide, head and hooves were sampled quantitatively. Three reindeer were pregnant and also the foetuses were studied. The Cs-137 amounts were determined by gammaspectrometric measurements. The results showed that the differences in the Cs-137 concentrations between muscle tissue from different parts of an individual reindeer were not more than 10 percent. Thus it is not essential from which part of the reindeer meat samples for surveillance purposes are taken. The concentration of Cs-137 in edible tissues other than muscle was lower except in the kidneys and scapula cartilage.

  1. Total body irradiation with a reconditioned cobalt teletherapy unit.

    Science.gov (United States)

    Evans, Michael D C; Larouche, Renée-Xavière; Olivares, Marina; Léger, Pierre; Larkin, Joe; Freeman, Carolyn R; Podgorsak, Ervin B

    2006-01-01

    While the current trend in radiotherapy is to replace cobalt teletherapy units with more versatile and technologically advanced linear accelerators, there remain some useful applications for older cobalt units. The expansion of our radiotherapy department involved the decommissioning of an isocentric cobalt teletherapy unit and the replacement of a column-mounted 4-MV LINAC that has been used for total body irradiation (TBI). To continue offering TBI treatments, we converted the decommissioned cobalt unit into a dedicated fixed-field total body irradiator and installed it in an existing medium-energy LINAC bunker. This article describes the logistical and dosimetric aspects of bringing a reconditioned cobalt teletherapy unit into clinical service as a total body irradiator.

  2. Effects of filters and wedges on skin sparing and gamma/neutron dose ratios in neutron teletherapy.

    Science.gov (United States)

    Smathers, J; Graves, R; Almond, P; Otte, V; Grant, W

    1980-01-01

    The effects of skin sparing and the gamma/neutron dose ratios in the clinical situations presently in use at the TAMVEC neutron teletherapy facility are not appreciably affected by the presence of filters and/or wedges. It is also shown that if skin sparing is lost due to close proximity of a hydrogenous scattering source, it can be restored by the use of thin lead filters.

  3. Human factors evaluation of teletherapy: Literature review. Volume 5

    Energy Technology Data Exchange (ETDEWEB)

    Henriksen, K.; Kaye, R.D.; Jones, R. [Hughes Training, Inc., Falls Church, VA (United States); Morisseau, D.S.; Serig, D.L. [Nuclear Regulatory Commission, Washington, DC (United States). Div. of Systems Technology

    1995-07-01

    A series of human factors evaluations were undertaken to better understand the contributing factors to human error in the teletherapy environment. Teletherapy is a multidisciplinary methodology for treating cancerous tissue through selective exposure to an external beam of ionizing radiation. A team of human factors specialists, assisted by a panel of radiation oncologists, medical physicists, and radiation therapists, conducted site visits to radiation oncology departments at community hospitals, university centers, and free-standing clinics. A function and task analysis was performed initially to guide subsequent evaluations in the areas of workplace environment, system-user interfaces, procedures, training, and organizational practices. To further acquire an in-depth and up-to-date understanding of the practice of teletherapy in support of these evaluations, a systematic literature review was conducted. Factors that have a potential impact on the accuracy of treatment delivery were of primary concern. The present volume is the literature review. The volume starts with an overview of the multiphased nature of teletherapy, and then examines the requirement for precision, the increasing role of quality assurance, current conceptualizations of human error, and the role of system factors such as the workplace environment, user-system interfaces, procedures, training, and organizational practices.

  4. Study of the 137Cs Stabilizer Source

    Directory of Open Access Journals (Sweden)

    GAO Yan;WANG Yan-ling;XU Zhi-jian;XU Liang;REN Chun-xia;TAN Xiao-ming;CUI Hong-qi

    2014-02-01

    Full Text Available The attenuation laws of the Cesium -137 γ-ray penetrating the ceramic core、stainless steel and tungsten steel were studied. The radioactivity of the 137Cs stabilizer source was determined through the surface dose rate of 137Cs stabilizer sources. In addition, the adsorption properties of the ceramic core were studied to improve the stability of the output rate, and established a production line. The application results showed that the output rate of ray source was accurate and was of a good consistency. At present, the source had been used in logging lithology, and achieved the realization of domestic product.

  5. Literature study of the radiobiological parameters of Caesium-137 required for evaluating internal irradiation doses as a function of age; Etude bibliographique des parametres radiobiologiques du cesium-137 necessaires a l'evaluation des doses d'irradiation interne en fonction de l'age

    Energy Technology Data Exchange (ETDEWEB)

    Garnier, A. [Commissariat a l' Energie Atomique, 92 - Fontenay-aux-Roses (France). Centre d' Etudes Nucleaires

    1968-07-01

    This document reassembles information published in scientific literature on radiobiological parameters of Cs-137, necessary for the estimate of the internal irradiation dose of man according to his age (during growth). The data are completed by a commented review of the mathematical models, proposed in order to value the irradiation doses from ingested cesium and the biological parameters. (author) [French] Ce document rassemble les informations publiees dans la litterature scientifique, concernant les parametres radiobiologiqueo du cesium-137, necessaires a l'evaluation des doses d'irradiation interne de l'homme en fonction de l'age. Ces donnees sont completees par une revue commentee des modeles mathematiques proposes en vue de l'evaluation des doses d'irradiation a partir des quantites de cesium ingerees et des parametres biologiques. (auteur)

  6. Viability of an isocentric cobalt-60 teletherapy unit for stereotactic radiosurgery.

    Science.gov (United States)

    Poffenbarger, B A; Podgorsak, E B

    1998-10-01

    The potential for radiosurgery with an isocentric teletherapy cobalt unit was evaluated in three areas: (1) the physical properties of radiosurgical beams, (2) the quality of radiosurgical dose distributions obtained with four to ten noncoplanar converging arcs, and (3) the accuracy with which the radiosurgical dose can be delivered. In each of these areas the cobalt unit provides a viable alternative to an isocentric linear accelerator (linac) as a radiation source for radiosurgery. A 10 MV x-ray beam from a linac used for radiosurgery served as a standard for comparison. The difference between the 80%-20% penumbras of stationary radiosurgical fields in the nominal diameter range from 10 to 40 mm of the cobalt-60 and 10 MV photon beams is remarkably small, with the cobalt-60 beam penumbras, on average, only about 0.7 mm larger than those of the linac beam. Differences between the cobalt-60 and 10 MV radiosurgical treatment plans in terms of dose homogeneity within the target volume, conformity of the prescribed isodose volume to the target volume, and dose falloffs outside the target volume are also minimal, and therefore of essentially no clinical significance. Moreover, measured isodose distributions for a radiosurgical procedure on our Theratron T-780 cobalt unit agreed with calculated distributions to within the +/- 1 mm spatial and +/- 5% numerical dose tolerances, which are generally specified for radiosurgery. The viability of isocentric cobalt units for radiosurgery will be of particular interest to centers in developing countries where cobalt units, because of their relatively low costs, provide the only megavoltage source of radiation for radiotherapy, and could easily and inexpensively be modified for radiosurgery. Of course, the quality assurance protocols and mechanical condition of a particular teletherapy cobalt unit must meet stringent requirements before the use of the unit for radiosurgery can be advocated.

  7. Human factors evaluation of teletherapy: Training and organizational analysis. Volume 4

    Energy Technology Data Exchange (ETDEWEB)

    Henriksen, K.; Kaye, R.D.; Jones, R. [Hughes Training, Inc., Falls Church, VA (United States); Morisseau, D.S.; Serig, D.I. [Nuclear Regulatory Commission, Washington, DC (United States). Div. of Systems Technology

    1995-07-01

    A series of human factors evaluations were undertaken to better understand the contributing factors to human error in the teletherapy environment. Teletherapy is a multidisciplinary methodology for treating cancerous tissue through selective exposure to an external beam of ionizing radiation. A team of human factors specialists, assisted by a panel of radiation oncologists, medical physicists, and radiation therapists, conducted site visits to radiation oncology departments at community hospitals, university centers, and free-standing clinics. A function and task analysis was initially performed to guide subsequent evaluations in the areas of system-user interfaces, procedures, training and qualifications, and organizational policies and practices. The present work focuses solely on training and qualifications of personnel (e.g., training received before and during employment), and the potential impact of organizational factors on the performance of teletherapy. Organizational factors include such topics as adequacy of staffing, performance evaluations, commonly occurring errors, implementation of quality assurance programs, and organizational climate.

  8. a Biokinetic Model for CESIUM-137 in the Fetus

    Science.gov (United States)

    Jones, Karen Lynn

    1995-01-01

    Previously, there was no method to determine the dose to the embryo, fetus, fetal organs or placenta from radionuclides within the embryo, fetus, or placenta. In the past, the dose to the fetus was assumed to be equivalent to the dose to the uterus. Watson estimated specific absorbed fractions from various maternal organs to the uterine contents which included the fetus, placenta, and amniotic fluid and Sikov estimated the absorbed dose to the embryo/fetus after assuming 1 uCi of radioactivity was made available to the maternal blood.^{1,2} However, this method did not allow for the calculation of a dose to individual fetal organs or the placenta. The radiation dose to the embryo or fetus from Cs-137 in the fetus and placenta due to a chronic ingestion by the mother was determined. The fraction of Cs-137 in the maternal plasma crossing the placenta to the fetal plasma was estimated. The absorbed dose from Cs-137 in each modelled fetal organ was estimated. Since there has been more research regarding potassium in the human body, and particularly in the pregnant woman, a biokinetic model for potassium was developed first and used as a basis and confirmation of the cesium model. Available pertinent information in physiology, embryology, biokinetics, and radiation dosimetry was utilized. Due to the rapid growth of the fetus and placenta, the pregnancy was divided into four gestational periods. The numerous physiological changes that occurred during pregnancy were considered and an appropriate biokinetic model was developed for each of the gestational periods. The amount of cesium in the placenta, embryo, and fetus was estimated for each period. The dose to the fetus from cesium deposited in the embryo or fetus and in the placenta was determined for each period using Medical Internal Radiation Dosimetry (MIRD) methodology. An uncertainty analysis was also performed to account for the variability of the parameters in the biokinetic model based on the experimental data. The uncertainty in the dose estimate was calculated by propagation of errors after determining the uncertainty in the fetal and placenta mass estimates and the effective half-life.

  9. Protection Against Radiations from Radium, Cobalt-60, and Cesium-137

    Science.gov (United States)

    1954-09-01

    be large enough for easy threading. Thread ends subject to fraying should be pre- pared with beeswax or plastic. Screw threads should be carefully cut...separate washings should be performed. Highly alkaline soaps, abrasives, organic solvents , or cleaners that tend to increase permeability of the skin should

  10. Soil Organic Carbon Erosion Assessment by Cesium-137

    Energy Technology Data Exchange (ETDEWEB)

    Hao, Yueli; Lal, Rattan; Owens, Lloyd; Izaurralde, Roberto C.

    2001-12-31

    Soil organic carbon (SOC) is a major pool that impacts the global carbon cycle (Lal,1999). Increasing SOC pool is desirable because of its favorable effects on improving soil fertility, decreasing water and air pollution, and mitigating the greenhouse effect caused by various energy utilization activities such as fossil fuel combustion. The amount of SOC depends on kinetic competition between various input and output processes. The input processes include plant growth (plant residue, root excretion, and organic matter through-fall), addition of organic material (manure, sewage sludge, and other organic wastes) through soil management, and deposition through soil erosion. The output processes comprise decomposition into gases, leaching into groundwater, and removal through soil erosion. Assessment of these processes is one of the steps toward adopting the strategy of increasing SOC content.

  11. An Exploratory Investigation of e-REST: Teletherapy for Chronically Agrammatic Speakers

    Directory of Open Access Journals (Sweden)

    Marina B. Ruiter

    2016-07-01

    Full Text Available Delivering aphasia therapy via telecommunication may provide a means to deliver intensive therapy in a cost-effective way. Teletherapy, remotely-administered (language treatment, may support the repetitive drill practices that people with chronic aphasia need to perform when learning to compensate for their lasting language difficulties. The use of teletherapy may allow speech and language pathologists (SLPs to focus in-person sessions more strongly on the generalisation of therapy effects to daily life. This single subject study is an investigation whether a teletherapy application called e-REST meets the criteria of accessibility, user-friendliness, as well as effectiveness. e-REST, the teletherapy version of the Dutch and adapted Reduced Syntax Therapy, teaches chronically aphasic speakers of Dutch who experience difficulties in sentence production to convey their messages in a kind of telegraphic style. The results obtained suggest that it is reasonable to conduct a larger study into the user-friendliness, accessibility, effectiveness, and cost-effectiveness of e-REST.

  12. Radiological protection and calibration of an activity meter with cesium and barium sources in a nuclear medicine center; Proteccion radiologica y calibracion de un activimetro con fuentes de cesio y bario en un centro de medicina nuclear

    Energy Technology Data Exchange (ETDEWEB)

    Morales L, M.E. [IPEN INEN Centro de Medicina Nuclear, Av. Aviacion 3799, Lima 34 (Peru)

    2005-07-01

    Presently work is shown the results when gauging a team Deluxe Isotope (Caliper 11) with some sources of Cesium 137 and Barium 133, in a Center of Medicine Nuclear that operates from the anus 1983 in a modern building inside the one Institute of Illnesses Neoplasia (Inn). This Center was equipped initially with teams donated by the International Organism of Atomic Energy (Oa) with those that it develops assistance, educational works and of investigation, giving services to patient of the Inn and other public and private medical centers. (Author)

  13. Study of the spatial distribution of the absorbed dose in blood volumes irradiated using a teletherapy unit

    Energy Technology Data Exchange (ETDEWEB)

    Goes, E.G., E-mail: eggoes@terra.com.b [Regional Blood Center of Ribeirao Preto, Ribeirao Preto, SP (Brazil); Nicolucci, P.; Nali, I.C. [Physics and Mathematics Department, University of Sao Paulo, Ribeirao Preto, SP (Brazil); Pela, C.A.; Bruco, J.L. [Physics and Mathematics Department, University of Sao Paulo, Ribeirao Preto, SP (Brazil); Center of Instrumentation, Dosimetry and Radioprotection, University of Sao Paulo, Ribeirao Preto, SP (Brazil); Borges, J.C. [Center of Instrumentation, Dosimetry and Radioprotection, University of Sao Paulo, Ribeirao Preto, SP (Brazil); Covas, D.T. [Regional Blood Center of Ribeirao Preto, Ribeirao Preto, SP (Brazil); Center for Cell-Based Therapy, Ribeirao Preto Medical School, University of Sao Paulo, Ribeirao Preto, SP (Brazil)

    2010-06-15

    Blood irradiation can be performed using a dedicated blood irradiator or a teletherapy unit. A thermal device providing appropriate storage conditions during blood components irradiation with a teletherapy unit has been recently proposed. However, the most appropriated volume of the thermal device was not indicated. The goal of this study was to indicate the most appropriated blood volume for irradiation using a teletherapy unit in order to minimize both the dose heterogeneity in the volume and the blood irradiation time using these equipments. Theoretical and experimental methods were used to study the dose distribution in the blood volume irradiated using a linear accelerator and a cobalt-60 therapy machine. The calculation of absorbed doses in the middle plane of cylindrical acrylic volumes was accomplished by a treatment planning system. Experimentally, we also used cylindrical acrylic phantoms and thermoluminescent dosimeters to confirm the calculated doses. The data obtained were represented by isodose curves. We observed that an irradiation volume should have a height of 28 cm and a diameter of 28 cm and a height of 35 cm and a diameter of 35 cm, when the irradiation is to be performed by a linear accelerator and a cobalt-60 teletherapy unit, respectively. Calculated values of relative doses varied from 93% to 100% in the smaller volume, and from 66% to 100% in the largest one. A difference of 5.0%, approximately, was observed between calculated and experimental data. The size of these volumes permits the irradiation of blood bags in only one bath without compromising the homogeneity of the absorbed dose over the irradiated volume. Thus, these irradiation volumes can be recommend to minimize the irradiation time when a teletherapy unit is used to irradiate blood.

  14. Study of the spatial distribution of the absorbed dose in blood volumes irradiated using a teletherapy unit

    Science.gov (United States)

    Góes, E. G.; Nicolucci, P.; Nali, I. C.; Pelá, C. A.; Bruço, J. L.; Borges, J. C.; Covas, D. T.

    2010-06-01

    Blood irradiation can be performed using a dedicated blood irradiator or a teletherapy unit. A thermal device providing appropriate storage conditions during blood components irradiation with a teletherapy unit has been recently proposed. However, the most appropriated volume of the thermal device was not indicated. The goal of this study was to indicate the most appropriated blood volume for irradiation using a teletherapy unit in order to minimize both the dose heterogeneity in the volume and the blood irradiation time using these equipments. Theoretical and experimental methods were used to study the dose distribution in the blood volume irradiated using a linear accelerator and a cobalt-60 therapy machine. The calculation of absorbed doses in the middle plane of cylindrical acrylic volumes was accomplished by a treatment planning system. Experimentally, we also used cylindrical acrylic phantoms and thermoluminescent dosimeters to confirm the calculated doses. The data obtained were represented by isodose curves. We observed that an irradiation volume should have a height of 28 cm and a diameter of 28 cm and a height of 35 cm and a diameter of 35 cm, when the irradiation is to be performed by a linear accelerator and a cobalt-60 teletherapy unit, respectively. Calculated values of relative doses varied from 93% to 100% in the smaller volume, and from 66% to 100% in the largest one. A difference of 5.0%, approximately, was observed between calculated and experimental data. The size of these volumes permits the irradiation of blood bags in only one bath without compromising the homogeneity of the absorbed dose over the irradiated volume. Thus, these irradiation volumes can be recommend to minimize the irradiation time when a teletherapy unit is used to irradiate blood.

  15. Specification of High Activity Gamma-Ray Sources.

    Science.gov (United States)

    International Commission on Radiation Units and Measurements, Washington, DC.

    The report is concerned with making recommendations for the specifications of gamma ray sources, which relate to the quantity of radioactive material and the radiation emitted. Primary consideration is given to sources in teletherapy and to a lesser extent those used in industrial radiography and in irradiation units used in industry and research.…

  16. The Calibration of GR320 Gamma Ray Spectrometer With Manmade Radionuclide Planar Source%GR320 γ能谱仪人工核素面源刻度

    Institute of Scientific and Technical Information of China (English)

    王景丹; 倪卫冲

    2012-01-01

    This article introduces the method, experiment and application of calibration for GR320 gamma ray spectrometer with manmade nuclide planar source. Efficiency parameter of Cesium-137 and Cobalt-60 manmade nuclide, was obtained by simulating the infinite planar source with finite planar source, and the GR320 gamma ray spectrometer can detect the surface specific activity of Cesium-137 and Cobalt-60 in surveying the gamma ray radiation of environment. By checking "airborne hot-point" in Xinjiang with GR320 gamma ray spectrometer, the airborne anomaly was validated with Cesium-137, and the was cor-respondant to the in-situ tested result of HPGe spectrometer. Therefore the method can be used to calibrate other-type portable gamma ray spectrometer and other manmade nuclide planar source.%介绍了GR320 γ能谱仪人工核素面源刻度原理和方法、刻度实验过程以及对刻度结果的应用.通过人工核素小面源模拟大面源的刻度,得到人工核素137Cs和60Co面源的效率因子,使GR320 γ能谱仪在进行环境放射性γ辐射水平调查中能够定量给出人工核素137Cs和60Co的面活度.对新疆某地航测异常的地面验证测量结果表明,该航测异常地表确实存在人工核素137Cs,且GR320γ能谱仪测量的面活度结果与该异常就地HPGe谱仪的测量结果基本相符.此法可推广到其它型号的便携式γ能谱仪的刻度,也可扩展到其它人工核素面源的刻度.

  17. Development of sealed radioactive sources immobilized in epoxy resin for verification of detectors used in nuclear medicine; Desenvolvimento de fontes radioativas seladas imobilizadas em resina epoxi para verificacao de detectores utilizados em medicina nuclear

    Energy Technology Data Exchange (ETDEWEB)

    Tiezzi, Rodrigo

    2016-07-01

    The radioactive sealed sources are used in verification ionization chamber detectors, which measure the activity of radioisotopes used in several areas, such as in nuclear medicine. The measurement of the activity of radioisotopes must be made with accuracy, because it is administered to a patient. To ensure the proper functioning of the ionization chamber detectors, standardized tests are set by the International Atomic Energy Agency (IAEA) and the National Nuclear Energy Commission using sealed radioactive sources of Barium-133, Cesium-137 and Cobalt-57. The tests assess the accuracy, precision, reproducibility and linearity of response of the equipment. The focus of this work was the study and the development of these radioactive sources with standard Barium-133 and Cesium-137,using a polymer, in case commercial epoxy resin of diglycidyl ether of bisphenol A (DGEBA) and a curing agent based on modified polyamine diethylenetriamine (DETA), to immobilize the radioactive material. The polymeric matrix has the main function of fix and immobilize the radioactive contents not allowing them to leak within the technical limits required by the standards of radiological protection in the category of characteristics of a sealed source and additionally have the ability to retain the emanation of any gases that may be formed during the manufacture process and the useful life of this artifact. The manufacturing process of a sealed source standard consists of the potting ,into bottle standardized geometry, in fixed volume of a quantity of a polymeric matrix within which is added and dispersed homogeneously to need and exact amount in activity of the radioactive materials standards. Accordingly, a study was conducted for the choice of epoxy resin, analyzing its characteristics and properties. Studies and tests were performed, examining the maximum miscibility of the resin with the water (acidic solution, simulating the conditions of radioactive solution), loss of mechanical and

  18. Skin Dosimetry in Breast Teletherapy on a Phantom Anthropomorphic and Anthropometric Phantom

    Energy Technology Data Exchange (ETDEWEB)

    Batista Nogueira, Luciana [Anatomy and Imaging Department, Federal University of Minas Gerais, Belo Horizonte (Brazil); Lemos Silva, Hugo Leonardo [Santa Casa Hospital, Belo Horizonte (Brazil); Donato da Silva, Sabrina; Passos Ribeiro Campos, Tarcisio [Nuclear Engineering Department, Federal University of Minas Gerais, Belo Horizonte (Brazil)

    2015-07-01

    This paper addresses the breast teletherapy dosimetry. The goal is to evaluate and compare absorbed doses in equivalent skin tissue, TE-skin, of an anthropomorphic and anthropometric breast phantom submitted to breast radiotherapy. The methodology involved the reproduction of a set of tomographic images of the phantom; the elaboration of conformational radiotherapy planning in the SOMAVISION and CadPlan (TPS) software; and the synthetic breast irradiation by parallel opposed fields in 3D conformal teletherapy at 6 MV linear accelerator Clinac-2100 C from VARIAN with prescribed dose (PD) of 180 cGy to the target volume (PTV), referent to the glandular tissue. Radiochromic films EBT2 were selected as dosimeters. Two independent calibration processes of films with solid water Gammex 457 plates and water filled box were produced. Curves of optical density (OD) versus absorbed dose were produced. Dosimeters were positioned in the external region of the breast phantom in contact with TE-skin, area of 4.0 cm{sup 2} each. The irradiation process was prepared in duplicate to check the reproducibility of the technique. The radiochromic films were scanned and their response in RGB (Red, Green, Blue) analyzed by the ImageJ software. The optical density was obtained and converted to dose based on the calibration curves. Thus, the spatial dose distribution in the skin was reproduced. The absorbed doses measured on the radiochromic films in TE-skin showed values between upper and lower quadrants at 9 o'clock in the range of 54% of PD, between the upper and lower quadrants 3 o'clock in the range of 72% and 6 o'clock at the lower quadrant in the range of 68 % of PD. The values are ±64% (p <0.05) according to the TPS. It is concluded that the depth dose measured in solid water plates or water box reproduce equivalent dose values for both calibration processes of the radiochromic films. It was observed that the skin received doses ranging from 50% to 78% of the

  19. Low-dose fractionated percutaneous teletherapy in age-related macular degeneration with subfoveolar neovascularization - 3 year results; 3 Jahre Erfahrung mit der niedrig dosierten fraktionierten perkutanen Teletherapie bei subfoveolaeren Neovaskularisationen. Klinische Ergebnisse

    Energy Technology Data Exchange (ETDEWEB)

    Schittkowski, M.; Schneider, H.; Guthoff, R. [Universitaetsaugenklinik Rostock (Germany); Grueschow, K.; Ziegler, P.G.; Fietkau, R. [Zentrum fuer Radiologie, Univ. Rostock (Germany)

    2001-07-01

    The effect of low dose fractionated percutaneous teletherapy to visual acuity and the changes in subfoveolar neovascular membranes in age-related macular degeneration were investigated. Patients and Method: 126 eyes of 118 patients (age 55-89 years; mean 74 ys.) were treated. Best distal and near visual acuity was assessed prior to (= initial visual acuity [IVA]) and 3, 6, 12, 18, 24, and 36 months after teletherapy. Fluorescein angiography was performed prior to and 6, 12, 24 and 36 months after radiation therapy. For analysis patients were divided into different groups by IVA and membrane size. Maximal duration of observation was 36 months. Teletherapy was done by a 9-MeV photon linear accelerator through a lateral port in half-beam technique with a single dose of 2 Gy up to a total dose of 20 Gy within 12 days. Results: No severe negative side effects have been observed. Eight patients reported of epiphora and four patients complained of transient sicca syndrome. Visual acuity decreased more than one line in the group IVA 0.05-0.2. The group IVA 0.3-0.5 remained unchanged for 1 year. We found a tendency for increased visual acuity in group IVA {>=} 0.6 for 18 months. After that time both groups showed decreased visual acuity, but all these patients reported of reduced metamorphopsia and increased color and contrast perception. Conclusions: There is an influence of low dose fractionated percutaneous teletherapy on visual acuity, subfoveal neovascular membranes and metamorphopsia. IVA and duration of anamnesis play an important role. There seems to be no persistent effect; possibly increased dosage will bring a benefit. (orig.) [German] Es wurde die Wirkung der Bestrahlung auf die Sehschaerfe bei altersabhaengiger Makuladegeneration mit chorioidalen Neovaskularisationen, die nach den MPS-Kriterien einer Laserkoagulation nicht zugaenglich sind, untersucht. Patienten und Methode: 126 Augen von 118 Patienten im Alter von 55-89 Jahren (Mittel 74) wurden behandelt. Ein

  20. Radiological protection and routinary controls of an activimeter with a cesium and barium sources in an nuclear medicine center; Proteccion radiologica y controles rutinarios de un activimetro con fuentes de cesio y bario en un centro de medicina nuclear

    Energy Technology Data Exchange (ETDEWEB)

    Morales L, M.E. [IPEN INEN, Centro de Medicina Nuclear, Av. Aviacion 3799, Lima 34 (Peru)]. e-mail: toyoco3000@hotmail.com

    2006-07-01

    In the present work the results when carrying out the routine controls in a Deluxe Isotope (Calibrator II) equipment, with some sources of Cesium 137 and Barium 133, in a Nuclear Medicine Center that operates from the year 1983 in a modern one construction inside the Institute of Neoplastic Illnesses (INEN) are shown. Taking in account the Radiological Protection measures to verify if the equipment responds to the personnel's demands in the measurements of activities of the diverse radionuclides that are used in different types of exams that are carried out in this Nuclear Medicine Center are the objectives of this work. This Center was equipped initially with donated equipment by the International Atomic Energy Agency (IAEA) with those that it develops assistance, educational works and of research, giving services to patients of the INEN and other public and private medical centers. (Author)

  1. Validation of in-house treatment planning system software for cobalt-60 teletherapy unit at two radiotherapy installations

    Science.gov (United States)

    Mu'minah, I. A. S.; Toresano, L. O. H. Z.; Wibowo, W. E.; Sugiyantari; Pawiro, S. A.

    2016-03-01

    DSSuperDose v.1.0 is an in-house treatment planning system (TPS) developed by Medical Physics and Biophysics Laboratory (LFMB) Universitas Indonesia as a treatment planning software for Cobalt-60 teletherapy unit. The main objective of this study was the validation of in-house TPS calculation as an essential part in quality assurance (QA) of radiotherapy. Validation of an in-house TPS was performed with two Cobalt-60 teletherapy units by comparison between in-house TPS and ISIS TPS and by measurements of absorbed dose. Mean dose deviations between in-house TPS and measurement were (1.97 ± 2.42)% for open field, (1.32 ± 1.30)% for tray field, and (2.91 ± 2.36)% for wedge field treatments. In-house TPS provide optimal planning for open and tray beam conditions with depth fewer than 10 cm (≤ 10 cm) and field sizes up to 20×20 cm2, while for wedge beam conditions with field sizes fewer than the physical size of the wedge. Comparison of in-house TPS and ISIS TPS demonstrated a good match of 96%. From the results, it is concluded that DSSuperDose v.1.0 is adequately accurate for treatment planning of radiotherapy.

  2. Reconstruction and analysis of cesium-137 fallout deposition patterns in the Marshall Islands

    Science.gov (United States)

    Whitcomb, Robert Cleckley, Jr.

    Estimates of 137Cs deposition due to fallout originating from nuclear weapons testing in the Marshall Islands have been made for several locations in the Marshall Islands. These retrospective estimates were based primarily on historical exposure rate and gummed film measurements. The methods used to reconstruct these deposition estimates are specific for six of the Pacific tests. These methods are also similar to those used in the National Cancer Institute study for reconstructing 131I deposition from the Nevada Test Site. Reconstructed cumulative deposition estimates are validated against contemporary measurements of 137Cs concentration in soil. This validation work also includes an accounting for estimated global fallout contributions. These validations show that the overall geometric bias in predicted-to-observed (P/O) ratios is 1.0 (indicating excellent agreement). The 5th and 95th percentile range of this distribution is 0.35--2.95. The P/O ratios for estimates using historical gummed film measurements tend to slightly over-predict more than estimates using exposure rate measurements. The methods produce reasonable estimates of deposition confirming that radioactive fallout occurred at atolls further south of the four northern atolls recognized by the Department of Energy as being affected by fallout. The deposition estimate methods, supported by the very good agreement between estimates and measurements, suggest that these methods can be used for other weapons testing fallout radionuclides with confidence.

  3. AN OVERVIEW OF CESIUM-137 CONTAMINATION IN A SOUTHEASTERN SWAMP ENVIRONMENT

    Energy Technology Data Exchange (ETDEWEB)

    Fledderman, P; Tim Jannik, T; Michael Paller, M

    2006-10-09

    In the early 1960s, an area of privately owned swamp adjacent to the Savannah River Site (SRS) was contaminated by site operations. Studies conducted in 1974 estimated that approximately 925 GBq of {sup 137}Cs and 37 GBq of {sup 60}Co were deposited in the swamp. Subsequently, a series of surveys was initiated to characterize the contaminated environment. These surveys--composed of 52 monitoring locations--allow for continued monitoring at a consistent set of locations. Initial survey results indicated maximum {sup 137}Cs concentrations of 19.5 Bq g{sup -1} in soil and 8.7 Bq g{sup -1} in vegetation. By the 2004-2005 surveys, maximum concentrations had declined to 1-2 Bq g{sup -1} in soil and 0.4 Bq g{sup -1} in vegetation.

  4. AN OVERVIEW OF CESIUM-137 CONTAMINATION IN A SOUTHEASTERN SWAMP ENVIRONMENT

    Energy Technology Data Exchange (ETDEWEB)

    Fledderman, P; Tim Jannik, T; Michael Paller, M

    2007-04-04

    In the early 1960s, an area of privately owned swamp adjacent to the Savannah River Site (SRS) was contaminated by site operations. Studies conducted in 1974 estimated that approximately 925 GBq of {sup 137}Cs and 37 GBq of {sup 60}Co were deposited in the swamp. Subsequently, a series of surveys was initiated to characterize the contaminated environment. These surveys--composed of 52 monitoring locations--allow for continued monitoring at a consistent set of locations. Initial survey results indicated maximum {sup 137}Cs concentrations of 19.5 Bq g{sup -1} in soil and 8.7 Bq g{sup -1} in vegetation. By the 2004-2005 surveys, maximum concentrations had declined to 1-2 Bq g{sup -1} in soil and 0.4 Bq g{sup -1} in vegetation.

  5. Wide Area Recovery and Resiliency Program (WARRP) Interim Clearance Strategy for Environments Contaminated with Cesium-137

    Science.gov (United States)

    2012-07-01

    Goiania ) and those containing 137Cs and other radionuclides (Chernobyl). Another group contains documents relevant to site survey 3 procedures...immediate and effective recovery (as was done in Goiania , Brazil). It is possible to graphically display the spectrum of clearance levels from

  6. Ruthenium-103, iodine-131, tellurium-132, and cesium-137 in air after the Chernobyl event

    Energy Technology Data Exchange (ETDEWEB)

    Liu, C.K.; Faller, S.H.; Kuroda, P.K. (Environmental Protection Agency, Las Vegas, NV (USA). Environmental Monitoring Systems Lab.)

    1990-01-01

    Concentrations of airborne fission products during the month following the Chernobyl event, were analyzed by gamma-ray counting of 283 air filter samples that were collected at 20 different locations in the western United States. While the presence of {sup 103}Ru, {sup 131}I, {sup 134}Cs and {sup 137}Cs was detected in many of the air filter samples, 78.2-hour {sup 132}Te was detected in only 19 samples all from the sampling stations located in the State of Nevada. The results obtained in this study indicate that the release of {sup 131}I from the Chernobyl reactor was roughly 50 percent greater than that of {sup 137}Cs, while the release of {sup 137}Cs was about 8 times that of {sup 103}Ru and 25 percent greater than that of {sup 132}Te. (orig.).

  7. Waste area Grouping 2 Phase I remedial investigation: Sediment and Cesium-137 transport modeling report

    Energy Technology Data Exchange (ETDEWEB)

    Clapp, R.B.; Bao, Y.S.; Moore, T.D.; Brenkert, A.L.; Purucker, S.T.; Reece, D.K.; Burgoa, B.B.

    1996-06-01

    This report is one of five reports issued in 1996 that provide follow-up information to the Phase I Remedial Investigation (RI) Report for Waste Area Grouping (WAG) 2 at Oak Ridge National Laboratory (ORNL). The five reports address areas of concern that may present immediate risk to public health at the Clinch River and ecological risk within WAG 2 at ORNL. A sixth report, on groundwater, in the series documenting WAG 2 RI Phase I results were part of project activities conducted in FY 1996. The five reports that complete activities conducted as part of Phase I of the Remedial Investigation (RI) for WAG 2 are as follows: (1) Waste Area Grouping 2, Phase I Task Data Report: Seep Data Assessment, (2) Waste Area Grouping 2, Phase I Task Data Report: Tributaries Data Assessment, (3) Waste Area Grouping 2, Phase I Task Data Report: Ecological Risk Assessment, (4) Waste Area Grouping 2, Phase I Task Data Report: Human Health Risk Assessment, (5) Waste Area Grouping 2, Phase I Task Data Report: Sediment and {sup 137}Cs Transport Modeling In December 1990, the Remedial Investigation Plan for Waste Area Grouping 2 at Oak Ridge National Laboratory was issued (ORNL 1990). The WAG 2 RI Plan was structured with a short-term component to be conducted while upgradient WAGs are investigated and remediated, and a long-term component that will complete the RI process for WAG 2 following remediation of upgradient WAGs. RI activities for the short-term component were initiated with the approval of the Environmental Protection Agency, Region IV (EPA), and the Tennessee Department of Environment and Conservation (TDEC). This report presents the results of an investigation of the risk associated with possible future releases of {sup 137}Cs due to an extreme flood. The results are based on field measurements made during storms and computer model simulations.

  8. Cesium-137 in deer: Savannah River Plant vs. southeastern coastal plain herds

    Energy Technology Data Exchange (ETDEWEB)

    Watts, J.R.; Rabon, E.W.; Dicks, A.S.

    1979-01-01

    The /sup 137/Cs content in deer killed during programmed hunts at the Savannah River Plant (SRP) has averaged 9.0 pCi/g. This value, based on measurements of 13,907 deer taken over 14 years (1965 to 1978), similar to the value obtained for 552 deer from other southeastern Coastal Plain locations, indicating the /sup 137/Cs content is due to fallout from the atmospheric testing of nuclear weapons rather than from SRP operations. The computerized SRP data base for each harvested deer includes age, sex, weight, cesium content, kill location, date, and the hunter's name. Analysis of these data enables the estimation of population dose from ingestion of the edible meat. Consumption of all edible meat from deer killed at SRP from 1965 to 1978 gives a whole body population dose of 196 man-rem from /sup 137/Cs. Assuming an annual consumption rate of 20 kg gives an average individual whole body dose of 13 mrem, about 10% of local annual background level. The radiation dose from /sup 40/K of natural potassium content of deer is comparable to the radiation dose from /sup 137/Cs.

  9. Pulsed redistribution of a contaminant following forest fire: cesium-137 in runoff.

    Science.gov (United States)

    Johansen, Mathew P; Hakonson, Thomas E; Whicker, F Ward; Breshears, David D

    2003-01-01

    Of the natural processes that concentrate dispersed environmental contaminants, landscape fire stands out as having potential to rapidly concentrate contaminants and accelerate their redistribution. This study used rainfall simulation methods to quantify changes in concentration of a widely dispersed environmental contaminant (global fallout 137Cs) in soils and surface water runoff following a major forest fire at Los Alamos, New Mexico, USA. The 137Cs concentrations at the ground surface increased up to 40 times higher in ash deposits and three times higher for the topmost 50 mm of soil compared with pre-fire soils. Average redistribution rates were about one order of magnitude greater for burned plots, 5.96 KBq ha(-1) mm(-1) rainfall, compared with unburned plots, 0.55 KBq ha(-1) mm(-1) rainfall. The greatest surface water transport of 137Cs, 11.6 KBq ha(-1) mm(-1), occurred at the plot with the greatest amount of ground cover removal (80% bare soil) following fire. Concentration increases of 137Cs occurred during surface water erosion, resulting in enrichment of 137Cs levels in sediments by factors of 1.4 to 2.9 compared with parent soils. The elevated concentrations in runoff declined rapidly with time and cumulative precipitation occurrence and approached pre-fire levels after approximately 240 mm of rainfall. Our results provide evidence of order-of-magnitude concentration increases of a fallout radionuclide as a result of forest fire and rapid transport of radionuclides following fire that may have important implications for a wide range of geophysical, ecosystem, fire management, and risk-based issues.

  10. Bioaccumulation of cesium-137 in yellow bullhead catfish (Ameiurus natalis) inhabiting an abandoned nuclear reactor reservoir

    Energy Technology Data Exchange (ETDEWEB)

    McCreedy, C.D.; Glickman, L.T. [Purdue Univ., West Lafayette, IN (United States). Dept. of Veterinary Pathobiology; Jagoe, C.H.; Brisbin, I.L. Jr. [Univ. of Georgia, Aiken, SC (United States). Savannah River Ecology Lab.

    1997-02-01

    Bioaccumulation of {sup 137}Cs was investigated in yellow bullhead catfish (Ameiurus natalis) inhabiting an abandoned reactor reservoir, Pond B, Savannah River Site, Barnwell Co., South Carolina. The authors collected fish by trap-netting, and determined ages from pectoral spines. Muscle and other tissues were assayed for {sup 137}Cs by NaI-scintillation. Music {sup 137}Cs was unrelated to sex or mass of fish, but was related to age. Examination of least-squares means suggested that {sup 137}Cs in muscle increased up to about age 3, but did not increase with greater age. A modified Richards model showed equilibrium {sup 137}Cs concentration in muscle was acquired in approximately 2.4 years. Growth differed between sexes and the time to asymptotic body mass was longer than the time to attain equilibrium {sup 137}Cs concentration. Males attained an asymptotic mass of 577 g in approximately 6.3 years; females attained an asymptotic mass of 438 g in approximately 5.9 years. The cumulative {sup 137}Cs burden of the population was 4.9 {times} 10{sup 6} Bq, representing <0.001% of the {sup 137}Cs inventory of the reservoir. Concentration of {sup 137}Cs varied among tissues with gill and muscle the lowest and highest. Concentration of {sup 137}Cs in ovaries declined with increasing ovary mass. Until equilibrium is attained in these fish, {sup 137}Cs concentration is directly related to increasing age rather than size.

  11. EFFECTIVE HALF-LIFE OF CESIUM-137 IN VARIOUS ENVIRONMENTAL MEDIA AT THE SAVANNAH RIVER SITE

    Energy Technology Data Exchange (ETDEWEB)

    Jannik, T.; Paller, M.; Baker, R.

    2013-12-12

    During the operational history of the Savannah River Site (SRS), many different radionuclides have been released from site facilities into the SRS environment. However, only a relatively small number of pathways, most importantly {sup 137}Cs in fish and deer, have contributed significantly to doses and risks to the public. The “effective” half-lives (T{sub e}) of {sup 137}Cs (which include both physical decay and environmental dispersion) in Savannah River floodplain soil and vegetation and in fish and white-tailed deer from the SRS were estimated using long-term monitoring data. For 1974–2011, the T{sub e}s of {sup 137}Cs in Savannah River floodplain soil and vegetation were 17.0 years (95% CI = 14.2–19.9) and 13.4 years (95% CI = 10.8–16.0), respectively. These T{sub e}s were greater than in a previous study that used data collected only through 2005 as a likely result of changes in the flood regime of the Savannah River. Field analyses of {sup 137}Cs concentrations in deer collected during yearly controlled hunts at the SRS indicated an overall T{sub e} of 15.9 years (95% CI = 12.3–19.6) for 1965–2011; however, the T{sub e} for 1990–2011 was significantly shorter (11.8 years, 95% CI = 4.8–18.8) due to an increase in the rate of {sup 137}Cs removal. The shortest T{sub e}s were for fish in SRS streams and the Savannah River (3.5–9.0 years), where dilution and dispersal resulted in rapid {sup 137}Cs removal. Long-term data show that T{sub e}s are significantly shorter than the physical half-life of {sup 137}Cs in the SRS environment but that they can change over time. Therefore, it is desirable have a long period of record for calculating Tes and risky to extrapolate T{sub e}s beyond this period unless the processes governing {sup 137}Cs removal are clearly understood.

  12. The migration of cesium-137 through cement formulations applicable to radioactive waste management

    Energy Technology Data Exchange (ETDEWEB)

    Rudin, M.J.

    1989-01-01

    Eighteen portland cement formulations containing three levels of cement/fly ash content (100%/0%, 85%/15%, and 60%/40%), two levels of water to cementitious solids ratio (0.33 and 0.43) and three levels of additive (none, silica fume, and latex polymer) were tested. Each formulation was molded into a solid cement specimen containing a centered well space which served as a reservoir for a {sup 137}Cs solution. After a predetermined time period, the {sup 137}Cs solution was removed and a 2-cm long by 1.27-cm diameter cement core was extracted from the monolith well bottom using a diamond core drill. Each cement core was then cut into successive horizontal slices with a diamond saw blade. The net activity of {sup 137}Cs in each slice was determined with a NaI(T1) detector connected to a single-channel analyzer. Analysis of variance (ANOVA) and regression models were used to examine the statistical relationship between different formulations in terms of the {sup 137}Cs activity in the cement slices versus the migration distance as indicated by the respective slice depths. Results indicated that mixes incorporating 5% silica fume at a low w/s ratio are relatively effective in retarding {sup 137}Cs migration when compared to the other formulations tested. Formulations with a w/s ratio of 0.33 consistently demonstrated better containment of the {sup 137}Cs solution compared to those formulations with a w/s ratio of 0.43. However, it was possible to obtain comparable {sup 137}Cs retardation at a higher w/s ratio if large amounts of fly ash were added to 5% EMSAC mixes at w/s = 0.43. The addition of 5% latex polymer did not improve the ability of cements to retard {sup 137}Cs ion migration under the curing conditions used.

  13. Distribution of cesium-137 in Japanese forest soils. Correlation with the contents of organic carbon

    Energy Technology Data Exchange (ETDEWEB)

    Takenaka, Chisato; Onda, Yuichi [School of Agricultural Science, Nagoya University, Chikusa-ku, Nagoya (Japan); Hamajima, Yasunori [Department of Chemistry, Kanazawa University, Kakuma, Kanazawa (Japan)

    1998-10-27

    The spatial and vertical distributions of {sup 137}Cs in surface soils were surveyed and analyzed then correlated with the contents of organic carbon in the hinoki (Chamaecyparis obtusa Sieb. et Zucc.) plantation forest and secondary forest dominated by red pine (Pinus densiflora Sieb. et Zucc.) in Japan. The spatial variation of {sup 137}Cs activity was observed in the surface soil around the red pine. The average activity of 16 samples around the tree is 42.4 Bq/kg and the standard deviation is 25.9 Bq/kg. This finding indicates the importance in the selection of a sampling site and the number of samples from the surface soils especially around a tree. For the vertical distribution of {sup 137}Cs activity, it was found that the concentration in the surface soil is highest, 149 Bq/kg in the hinoki stand and 101 Bq/kg in the red pine stand, and decreases with depth. The relationship between {sup 137}Cs activity and carbon content in the forest soil was investigated in two undisturbed forest stands. The relations were more precisely expressed using an exponential equation than by a linear equation. From the same forest, similar regression equations were obtained. This indicates that the distribution of {sup 137}Cs could be characterized by the organic carbon content in an undisturbed forest. It is also suggested that the coefficient values in the regression equation help to define the movement of {sup 137}Cs accompanying the decomposition of organic matter

  14. Depth distribution of cesium-137 in paddy fields across the Fukushima pollution plume in 2013.

    Science.gov (United States)

    Lepage, Hugo; Evrard, Olivier; Onda, Yuichi; Lefèvre, Irène; Laceby, J Patrick; Ayrault, Sophie

    2015-09-01

    Large quantities of radiocesium were deposited across a 3000 km(2) area northwest of the Fukushima Dai-ichi nuclear power plant after the March 2011 accident. Although many studies have investigated the fate of (137)Cs in soil in the months following the accident, the depth distribution of this radioactive contaminant in rice paddy fields requires further examination after the typhoons that occurred in this region. Such investigations will help minimize potential human exposure in rice paddy fields. Radionuclide activity concentrations, organic content and particle size were analysed in 10 soil cores sampled from paddy fields in November 2013, 20 km north of the Fukushima power plant. Our results demonstrate limited depth migration of (137)Cs with the majority concentrated in the uppermost layers of soils (accident, between 46.8 and 98.7% of the total (137)Cs inventories was found within the top 5 cm of the soil surface, despite cumulative rainfall totalling 3300 mm. Furthermore, there were no significant correlations between (137)Cs depth distribution and the other parameters. We attributed the maximum depth penetration of (137)Cs to grass cutting (73.6-98.5% of (137)Cs in the upper 5 cm) and farming operations (tillage - 46.8-51.6% of (137)Cs in the upper 5 cm). As this area is exposed to erosive events, ongoing decontamination works may increase soil erodibility. We therefore recommend the rapid removal of the uppermost - contaminated - layer of the soil after removing the vegetation to avoid erosion of contaminated material during the subsequent rainfall events. Further analysis is required to thoroughly understand the impacts of erosion on the redistribution of radiocesium throughout the Fukushima Prefecture.

  15. Assessment of Haptic Interaction for Home-Based Physical Tele-Therapy using Wearable Devices and Depth Sensors.

    Science.gov (United States)

    Barmpoutis, Angelos; Alzate, Jose; Beekhuizen, Samantha; Delgado, Horacio; Donaldson, Preston; Hall, Andrew; Lago, Charlie; Vidal, Kevin; Fox, Emily J

    2016-01-01

    In this paper a prototype system is presented for home-based physical tele-therapy using a wearable device for haptic feedback. The haptic feedback is generated as a sequence of vibratory cues from 8 vibrator motors equally spaced along an elastic wearable band. The motors guide the patients' movement as they perform a prescribed exercise routine in a way that replaces the physical therapists' haptic guidance in an unsupervised or remotely supervised home-based therapy session. A pilot study of 25 human subjects was performed that focused on: a) testing the capability of the system to guide the users in arbitrary motion paths in the space and b) comparing the motion of the users during typical physical therapy exercises with and without haptic-based guidance. The results demonstrate the efficacy of the proposed system.

  16. Characterization of radioactive orphan sources by gamma spectrometry; Caracterizacion de fuentes huerfanas radiactivas por espectrometria gamma

    Energy Technology Data Exchange (ETDEWEB)

    Cruz W, H., E-mail: wcruz@ipen.gob.pe [Instituto Peruano de Energia Nuclear (PGRR/IPEN), Lima (Peru). Planta de Gestion de Residuos Radiactivos

    2013-07-01

    The sealed radioactive sources are widely applicable in industry. They must have a permanent control and must be registered with the Technical Office of the National Authority (OTAN). However, at times it has identified the presence of abandoned sealed sources unknown to the owner. These sources are called 'orphan sources'. Of course these sources represent a high potential risk because accidents can trigger dire consequences depending on your activity and chemical form in which it presents the radioisotope. This paper describes the process and the actions taken to characterize two orphan radioactive sources from the smelter a Aceros Arequipa. For characterization we used a gamma spectrometry system using a detector NaI(Tl) 3″ x 3″ with a multichannel analyzer Nucleus PCA-II. The radioisotope identified was cesium - 137 ({sup 137}Cs) in both cases. Fortunately, the sources maintained their integrity would otherwise have generated significant pollution considering the chemical form of the radioisotope and easy dispersion. (author)

  17. Radioimmunoassay method suitable for analysis of salivary cortisol in patients with breast cancer in treatment by teletherapy - a preliminary study

    Energy Technology Data Exchange (ETDEWEB)

    Souza, Kellen Verena S. [Departamento de Engenharia Nuclear. Universidade Federal de Minas Gerais, Pampulha, MG (Brazil); Santos, Jane Lima dos [Departamento de Ciencias Biologicas, Universidade Estadual de Santa Cruz, Ilheus, BA (Brazil)

    2011-07-01

    Determination of salivary cortisol using radioimmunoassay and the relationship between stress levels were investigated before and after of the psychological intervention of 21 patients during teletherapy treatment of breast cancer. The benefits of psychological intervention during cancer treatment has been observed in some studies and evidence show that the patient's emotional state directly influences adherence to treatment, good prognosis and under stress. Thus, in present study 21 patients aged 50-70 years, females in the treatment of breast cancer at the Radiotherapy Service of Santa Casa de Misericordia in Belo Horizonte, were divided randomly into two groups: control (without psychological intervention) and Group TCC (with psychological intervention). Salivary cortisol concentrations are reportedly about 5.10% of those in serum, the levels has been used as an objective marker of hypothalamic-pituitary-adrenal (HPA) axis activity and avoided the confounding effects of venepuncture stress on cortisol levels. The assessment of cortisol in saliva has proven a valid and reliable measure of unbound steroid in the circulation. The salivary cortisol measured by radioimmunoassay in control patients and TCC showed no significant differences. The radioimmunoassay method show be suitable for analysis of salivary cortisol because allows measure low detection limits and have high sensibility. The values of TCC group and Control group were higher than reference values, except for one patient of the control group. At the beginning of treatment, both groups were homogeneous for Teletherapy. Both the TCC group as the control group had . 80% of participants in phase with stress. It was observed in the TCC group after radiotherapy showing a reversal 60% of participants without stress. The data show that cognitive-behavioral therapy has benefits for the control of psychological stress and enhance relevance of the psychologist to provide reduction or stress control during

  18. Physical characterization of single convergent beam device for teletherapy: theoretical and Monte Carlo approach.

    Science.gov (United States)

    Figueroa, R G; Valente, M

    2015-09-21

    The main purpose of this work is to determine the feasibility and physical characteristics of a new teletherapy device of radiation therapy based on the application of a convergent x-ray beam of energies like those used in radiotherapy providing highly concentrated dose delivery to the target. We have denominated it Convergent Beam Radio Therapy (CBRT). Analytical methods are developed first in order to determine the dosimetry characteristic of an ideal convergent photon beam in a hypothetical water phantom. Then, using the PENELOPE Monte Carlo code, a similar convergent beam that is applied to the water phantom is compared with that of the analytical method. The CBRT device (Converay(®)) is designed to adapt to the head of LINACs. The converging beam photon effect is achieved thanks to the perpendicular impact of LINAC electrons on a large thin spherical cap target where Bremsstrahlung is generated (high-energy x-rays). This way, the electrons impact upon various points of the cap (CBRT condition), aimed at the focal point. With the X radiation (Bremsstrahlung) directed forward, a system of movable collimators emits many beams from the output that make a virtually definitive convergent beam. Other Monte Carlo simulations are performed using realistic conditions. The simulations are performed for a thin target in the shape of a large, thin, spherical cap, with an r radius of around 10-30 cm and a curvature radius of approximately 70 to 100 cm, and a cubed water phantom centered in the focal point of the cap. All the interaction mechanisms of the Bremsstrahlung radiation with the phantom are taken into consideration for different energies and cap thicknesses. Also, the magnitudes of the electric and/or magnetic fields, which are necessary to divert clinical-use electron beams (0.1 to 20 MeV), are determined using electromagnetism equations with relativistic corrections. This way the above-mentioned beam is manipulated and guided for its perpendicular impact

  19. Development of sealed radioactive sources immobilized in epoxy resin for verification of detectors used in nuclear medicine

    Energy Technology Data Exchange (ETDEWEB)

    Tiezzi, Rodrigo; Rostelato, Maria Elisa C.M.; Nagatomi, Helio R.; Zeituni, Calos A.; Benega, Marcos A.G.; Souza, Daiane B. de; Costa, Osvaldo L. da; Souza, Carla D.; Rodrigues, Bruna T.; Souza, Anderson S. de; Peleias Junior, Fernando S.; Santos, Rafael Melo dos; Melo, Emerson Ronaldo de, E-mail: rktiezzi@gmail.com [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Karan Junior, Dib [Universidade de Sao Paulo (USP), Sao Paulo, SP (Brazil)

    2015-07-01

    The radioactive sealed sources are used in verification ionization chamber detectors, which measure the activity of radioisotopes used in several areas, such as in nuclear medicine. The measurement of the activity of radioisotopes must be made with accuracy, because it is administered to a patient. To ensure the proper functioning of the ionization chamber detectors, standardized tests are set by the International Atomic Energy Agency (IAEA) and the National Nuclear Energy Commission using sealed radioactive sources of Barium-133, Cesium-137 and Cobalt-57. The tests assess the accuracy, precision, reproducibility and linearity of response of the equipment. The focus of this work was the study and the development of these radioactive sources with standard Barium-133, Cesium-137 and Cobalt-57,using a polymer, in case commercial epoxy resin of diglycidyl ether of bisphenol A (DGEBA) and a curing agent based on modified polyamine diethylenetriamine (DETA), to immobilize the radioactive material. The polymeric matrix has the main function of fix and immobilize the radioactive contents not allowing them to leak within the technical limits required by the standards of radiological protection in the category of characteristics of a sealed source and additionally have the ability to retain the emanation of any gases that may be formed during the manufacture process and the useful life of this artifact. The manufacturing process of a sealed source standard consists of the potting ,into bottle standardized geometry, in fixed volume of a quantity of a polymeric matrix within which is added and dispersed homogeneously to need and exact amount in activity of the radioactive materials standards. Accordingly, a study was conducted for the choice of epoxy resin, analyzing its characteristics and properties. Studies and tests were performed, examining the maximum solubility of the resin in water (acidic solution, simulating the conditions of radioactive solution), loss of mechanical

  20. Combining Teletherapy and On-line Language Exercises in the Treatment of Chronic Aphasia: An Outcome Study

    Directory of Open Access Journals (Sweden)

    Richard D. Steele

    2015-01-01

    Full Text Available We report a 12-week outcome study in which nine persons with long-term chronic aphasia received individual and group speech-language teletherapy services, and also used on-line language exercises to practice from home between therapy sessions.  Participants were assessed at study initiation and completion using the Western Aphasia Battery, a portion of the Communicative Effectiveness Index, ASHA National Outcome Measurement System, and RIC Communication Confidence Rating Scale for Aphasia; additionally participants were polled regarding satisfaction at discharge.  Pre-treatment and post-treatment means were calculated and compared, and matched t-tests were used to determine significance of improvements following treatment, with patterns of independent on-line activity analyzed.  Analysis of scores shows that means improved on most measures following treatment, generally significantly: the WAB AQ improved +3.5 (p = .057; the CETI Overall (of items administered — +17.8 (p = .01, and CCRSA Overall — + 10.4 (p = .0004.  Independent work increased with time, and user satisfaction following participation was high.

  1. SU-E-T-559: Monte Carlo Simulation of Cobalt-60 Teletherapy Unit Modeling In-Field and Out-Of-Field Doses for Applications in Computational Radiation Dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Petroccia, H; Bolch, W [J. Crayton Pruitt Family of Biomedical Engineering, University of Florida, Gainesville, FL (United States); Li, Z; Mendenhall, N [Radiation Oncology, UF Health Proton Therapy Institute, Jacksonville, FL (United States)

    2015-06-15

    Purpose: Mean organ doses from structures located in field and outside of field boundaries during radiotherapy treatment must be considered when looking at secondary effects. Treatment planning in patients with 40 years of follow-up does not include 3-D treatment planning images and did not estimate dose to structures out of the direct field. Therefore, it is of interest to correlate actual clinical events with doses received. Methods: Accurate models of radiotherapy machines combined with whole body computational phantoms using Monte Carlo methods allow for dose reconstructions intended for studies on late radiation effects. The Theratron-780 radiotherapy unit and anatomically realistic hybrid computational phantoms are modeled in the Monte Carlo radiation transport code MCNPX. The major components of the machine including the source capsule, lead in the unit-head, collimators (fixed/adjustable), and trimmer bars are simulated. The MCNPX transport code is used to compare calculated values in a water phantom with published data from BJR suppl. 25 for in-field doses and experimental data from AAPM Task Group No. 36 for out-of-field doses. Next, the validated cobalt-60 teletherapy model is combined with the UF/NCI Family of Reference Hybrid Computational Phantoms as a methodology for estimating organ doses. Results: The model of Theratron-780 has shown to be agree with percentage depth dose data within approximately 1% and for out of field doses the machine is shown to agree within 8.8%. Organ doses are reported for reference hybrid phantoms. Conclusion: Combining the UF/NCI Family of Reference Hybrid Computational Phantoms along with a validated model of the Theratron-780 allows for organ dose estimates of both in-field and out-of-field organs. By changing field size, position, and adding patient-specific blocking more complicated treatment set-ups can be recreated for patients treated historically, particularly those who lack both 2D/3D image sets.

  2. Adaptive tele-therapies based on serious games for health for people with time-management and organisational problems: preliminary results.

    Science.gov (United States)

    Frutos-Pascual, Maite; Zapirain, Begoña García; Zorrilla, Amaia Méndez

    2014-01-07

    Attention Deficit with Hyperactivity Disorder (ADHD) is one of the most prevalent disorders within the child population today. Inattention problems can lead to greater difficulties in completing assignments, as well as problems with time management and prioritisation of tasks. This article presents an intelligent tele-therapy tool based on Serious Games for Health, aimed at the improvement of time management skills and the prioritisation of tasks. This tele-system is based on the use of decision trees within Django, a high-level Python Web framework. The technologies and techniques used were selected so as to boost user involvement and to enable the system to be easily customised. This article shows the preliminary results of the pilot-phase in an experiment performed to evaluate the use of adaptive tele-therapies within a group of typically developing children and adolescents aged between 12 and 19 years old without ADHD. To do so, we relied on the collection of parameters and the conduct of surveys for assessing time management skills, as well as measuring system usability and availability. The results of a time management survey highlighted that the users involved in the trial did not use any specific or effective time management techniques, scoring 1.98 and 2.30 out of 5 points in this area for ages under 15 and over 16 years old, respectively. The final calculations based on the usability questionnaire resulted in an average score of 78.75 out of 100. The creation of a customisable tool capable of working with different skills, in conjunction with the replication of the current study, may help to understand these users' needs, as well as boosting time management skills among teenagers with and without ADHD.

  3. 75 FR 37483 - Request for Comments on the Draft Policy Statement on the Protection of Cesium-137 Chloride...

    Science.gov (United States)

    2010-06-29

    ... biomedical research, CsCl irradiation has been used for over 40 years in fields such as immunology, stem cell research, cancer research, in-vivo immunology, systemic drug research, chromosome aberrations, DNA...

  4. γ-H2AX Kinetic Profile in Mouse Lymphocytes Exposed to the Internal Emitters Cesium-137 and Strontium-90.

    Directory of Open Access Journals (Sweden)

    Helen C Turner

    Full Text Available In the event of a dirty bomb scenario or an industrial nuclear accident, a significant dose of volatile radionuclides such as 137Cs and 90Sr may be dispersed into the atmosphere as a component of fallout and inhaled or ingested by hundreds and thousands of people. To study the effects of prolonged exposure to ingested radionuclides, we have performed long-term (30 day internal-emitter mouse irradiations using soluble-injected 137CsCl and 90SrCl2 radioisotopes. The effect of ionizing radiation on the induction and repair of DNA double strand breaks (DSBs in peripheral mouse lymphocytes in vivo was determined using the γ-H2AX biodosimetry marker. Using a serial sacrifice experimental design, whole-body radiation absorbed doses for 137Cs (0 to 10 Gy and 90Sr (0 to 49 Gy were delivered over 30 days following exposure to each radionuclide. The committed absorbed doses of the two internal emitters as a function of time post exposure were calculated based on their retention parameters and their derived dose coefficients for each specific sacrifice time. In order to measure the kinetic profile for γ-H2AX, peripheral blood samples were drawn at 5 specific timed dose points over the 30-day study period and the total γ-H2AX nuclear fluorescence per lymphocyte was determined using image analysis software. A key finding was that a significant γ-H2AX signal was observed in vivo several weeks after a single radionuclide exposure. A mechanistically-motivated model was used to analyze the temporal kinetics of γ-H2AX fluorescence. Exposure to either radionuclide showed two peaks of γ-H2AX: one within the first week, which may represent the death of mature, differentiated lymphocytes, and the second at approximately three weeks, which may represent the production of new lymphocytes from damaged progenitor cells. The complexity of the observed responses to internal irradiation is likely caused by the interplay between continual production and repair of DNA damage, cell cycle effects and apoptosis.

  5. Analysis of risk perception of teletherapy in radiotherapy services of Rio de Janeiro city, RJ, Brazil; Analise da percepcao de risco da teleterapia dos servicos de radioterapia da regiao metropolitana do Rio de Janeiro

    Energy Technology Data Exchange (ETDEWEB)

    Burgos, Adam F.; Paiva, Eduardo de [Instituto de Radioprotecao e Dosimetria (IRD/CNEN-RJ), Rio de Janeiro, RJ (Brazil); Souza, Roberto S. de, E-mail: adam@bolsista.ird.gov.br [Instituto Nacional de Cancer (INCA), Rio de Janeiro, RJ (Brazil). Programa de Qualidade em Radioterapia

    2015-12-15

    Currently there are few applications on the risk analysis procedures related to radiation therapy, especially in the practice of radiotherapy. The objective of this study was to analyze the perception of risk levels present in the practice of teletherapy (only the use of linear accelerators), through a form based on the risk matrix concept and a database (SEVRRA) containing information about the processes related to routine teletherapy. Was delivered to a medical physicist for each service, a form containing information relating to teletherapy procedure and an annex indicating how to fill it properly. The results show that, according to the opinion of 16 medical physicists participants, six of these analyzes showed a prioritized risk percentage above 50%, other five had a risk of prioritized percentage between 0 and 50%, and the remainder had a risk percentage prioritized null. Two steps groups had the highest incidence of cases classified with high and very high risk: records and treatment planning group and equipment group. It was then possible to find the most risk processes these steps groups. Finally, we performed an analysis of the effectiveness of the controls present in the proposed form. The four most incidents controls, three of them had a percentage efficiency above 80%, and viable its continuous use in the analyzed services, as well as serving as a recommendation for use in other services not analyzed. This study showed that, although there are considerable histories of accidents for teletherapy procedure, you can not only identify the risks of higher expression but also mitigate them, based on actions and appropriate recommendations for each case analyzed properly. (author)

  6. SU-E-T-93: Activation of Psoralen at Depth Using Kilovoltage X-Rays: Physics Considerations in Implementing a New Teletherapy Paradigm

    Energy Technology Data Exchange (ETDEWEB)

    Adamson, J; Yoon, P; Liu, L; Alcorta, D; Spector, N; Oldham, M [Duke University Medical Center, Durham, NC (United States); Nolan, M; Gieger, T [North Carolina State University, Raleigh, NC (United States); Walder, H; Fathi, Z; Beyer, W [Immunolight LLC, Detroit, MI (United States)

    2015-06-15

    Purpose: Psoralen is a UV-light activated anti-cancer biotherapeutic used for treating skin lesions (PUVA) and advanced cutaneous T-cell lymphoma (ECP). To date psoralen has not been used to treat deep seated tumors due to difficulty in generating UV-light at depth. We recently demonstrated psoralen activation at depth by introducing energy converting particles that absorb kV x-ray radiation and re-emit UV-light. Our in-vitro work found that 0.2–1Gy using 40–100kVp x-rays combined with psoralen and particles can induce a substantial apoptotic response beyond that expected from the sum of individual components. In preparation for a phase I clinical trial of canine companion animals, we address the physics and dosimetry considerations for applying this new teletherapy paradigm to an in-vivo setting. Methods: The kV on-board imaging (OBI) system mounted on a medical linear accelerator (Varian) was commissioned to deliver the prescribed dose (0.6Gy) using 80 and 100kVp. Dosimetric measurements included kVp, HVL, depth dose, backscatter factors, collimator and phantom scatter factors, field size factors, and blade leakage. Absolute dosimetry was performed following AAPM TG61 recommendations and verified with an independent kV dose meter. We also investigated collimated rotational delivery to minimize skin dose using simple dose calculations on homogeneous cylindrical phantoms. Results: Single beam delivery is feasible for shallow targets (<5cm) without exceeding skin tolerance, while a rotational delivery may be utilized for deeper targets; skin dose is ∼75% of target dose for 80kVp collimated rotational delivery to a 3cm target within a 20cm phantom. Heat loading was tolerable; 0.6Gy to 5cm can be delivered before the anode reaches 75% capacity. Conclusion: KV teletherapy for Psoralen activation in deep seated tissue was successfully commissioned for a Varian OBI machine for use in a phase I clinical trial in canines. Future work will use Monte Carlo dosimetry to

  7. sources

    Directory of Open Access Journals (Sweden)

    Shu-Yin Chiang

    2002-01-01

    Full Text Available In this paper, we study the simplified models of the ATM (Asynchronous Transfer Mode multiplexer network with Bernoulli random traffic sources. Based on the model, the performance measures are analyzed by the different output service schemes.

  8. Estimation of sediment sources using selected chemical tracers in the Perry lake basin,Kansas,USA

    Institute of Scientific and Technical Information of China (English)

    K.E.JURACEK; A.C.ZIEGLER

    2009-01-01

    The ability to achieve meaningful decreases in sediment loads to reservoirs requires a determination of the relative importance of sediment sources within the contributing basins.In an investigation of sources of fine-grained sediment (clay and silt) within the Perry Lake Basin in northeast Kansas,representative samples of channel-bank sources,surface-soil sources (cropland and grassland),and reservoir bottom sediment were collected,chemically analyzed,and compared.The samples were sieved to isolate the <63μ m fraction and analyzed for selected nutrients (total nitrogen and total phosphorus),organic and total carbon,25 trace elements,and the radionuclide cesium-137 (137Cs).On the basis of substantial and consistent compositional differences among the source types,total nitrogen (TN),total phosphorus (TP),total organic carbon (TOC),and 137Cs were selected for use in the estimation of sediment sources.To further account for differences in particle-size composition between the sources and the reservoir bottom sediment,constituent ratio and clay-normalization techniques were used.Computed ratios included TOC to TN,TOC to TP,and TN to TP.Constituent concentrations (TN,TP,TOC) and activities (137Cs) were normalized by dividing by the percentage of clay.Thus,the sediment-source estimations involved the use of seven sediment-source indicators.Within the Perry Lake Basin,the consensus of the seven indicators was that both channel-bank and surface-soil sources were important in the Atchison County Lake and Banner Creek Reservoir subbasins,whereas channel-bank sources were dominant in the Mission Lake subbasin.On the sole basis of 137Cs activity,surface-soil sources contributed the most fine-grained sediment to Atchison County Lake,and channel-bank sources contributed the most fine-grained sediment to Banner Creek Reservoir and Mission Lake.Both the seven-indicator consensus and 137Cs indicated that channelbank sources were dominant for Perry Lake and that channel

  9. Special Analysis for the Disposal of the Lawrence Livermore National Laboratory Low Activity Beta/Gamma Sources Waste Stream at the Area 5 Radioactive Waste Management Site, Nevada National Security Site, Nye County, Nevada

    Energy Technology Data Exchange (ETDEWEB)

    Shott, Gregory J. [National Security Technologies, LLC

    2015-06-01

    This special analysis (SA) evaluates whether the Lawrence Livermore National Laboratory (LLNL) Low Activity Beta/Gamma Sources waste stream (BCLALADOEOSRP, Revision 0) is suitable for disposal by shallow land burial (SLB) at the Area 5 Radioactive Waste Management Site (RWMS) at the Nevada National Security Site (NNSS). The LLNL Low Activity Beta/Gamma Sources waste stream consists of sealed sources that are no longer needed. The LLNL Low Activity Beta/Gamma Sources waste stream required a special analysis because cobalt-60 (60Co), strontium-90 (90Sr), cesium-137 (137Cs), and radium-226 (226Ra) exceeded the NNSS Waste Acceptance Criteria (WAC) Action Levels (U.S. Department of Energy, National Nuclear Security Administration Nevada Field Office [NNSA/NFO] 2015). The results indicate that all performance objectives can be met with disposal of the LLNL Low Activity Beta/Gamma Sources in a SLB trench. The LLNL Low Activity Beta/Gamma Sources waste stream is suitable for disposal by SLB at the Area 5 RWMS. However, the activity concentration of 226Ra listed on the waste profile sheet significantly exceeds the action level. Approval of the waste profile sheet could potentially allow the disposal of high activity 226Ra sources. To ensure that the generator does not include large 226Ra sources in this waste stream without additional evaluation, a control is need on the maximum 226Ra inventory. A limit based on the generator’s estimate of the total 226Ra inventory is recommended. The waste stream is recommended for approval with the control that the total 226Ra inventory disposed shall not exceed 5.5E10 Bq (1.5 Ci).

  10. Sources

    OpenAIRE

    2015-01-01

    SOURCES MANUSCRITES Archives nationales Rôles de taille 1768/71 Z1G-344/18 Aulnay Z1G-343a/02 Gennevilliers Z1G-340/01 Ivry Z1G-340/05 Orly Z1G-334c/09 Saint-Remy-lès-Chevreuse Z1G-344/18 Sevran Z1G-340/05 Thiais 1779/80 Z1G-391a/18 Aulnay Z1G-380/02 Gennevilliers Z1G-385/01 Ivry Z1G-387b/05 Orly Z1G-388a/09 Saint-Remy-lès-Chevreuse Z1G-391a/18 Sevran Z1G-387b/05 Thiais 1788/89 Z1G-451/18 Aulnay Z1G-452/21 Chennevières Z1G-443b/02 Gennevilliers Z1G-440a/01 Ivry Z1G-452/17 Noiseau Z1G-445b/05 ...

  11. Willow wood production on radionuclide polluted areas

    Directory of Open Access Journals (Sweden)

    Rodkin Oleg I.

    2010-01-01

    Full Text Available ABSTRACT: One of the key environmental problems in Belarus is effective use of agricultural lands contaminated by radionuclide due to the Chernobyl disaster. The alternative method to traditional agricultural crops is fast growing willow cultivation. It is possible to use biomass of willow as renewable energy source. The goal of our investigation was the estimation of environmental aspects of willow wood production on polluted areas. The field study experiments (2007-2010 were conducted at Krichev district of Mogilev region in eastern Belarus. This region characterized by high level of Cs-137 contamination as well as high level of heavy metals pollution. In the first stage of experiments, the concentration of cesium-137 in different parts of willow biomass had been measured and transfer factor calculated. The measuring had been done for leaves, roots, and wood. To control cesium-137 accumulation in willow biomass we apply different types (nitrogen N, phosphorus P and potassium K and dose of fertilizer. The experiments show that potassium mineral fertilizer is the key factor for radionuclide accumulation control. The optimal dose of potassium is 90 kg per hectare. On the base of experimental results the model of cesium-137 accumulation in the wood for a 21 year has been developed. In accordance with calculation to the end of willow cultivation (21 year concentration of cesium-137 in wood will not be higher than permitted even with the level of cesium-137 contamination in the soil 1480 kBq/m2 (maximum 140 kqB/m2 with permitted level for firewood is 740 Bq/kg.. The concentration of cesium-137 in the roots increases gradually and get maximum in 21 year (3000 kqB/m2. Our results confirm that in the sum about 0.8 million hectares of radionuclide polluted arable lands partly excluded from agricultural practice in Belarus could be used for willow biomass production.

  12. Using remote-sensing technologies in combination with Cesium-137 measurements to estimate soil-erosion quantity in semi-arid steppe areas

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    Soil erosion by wind is one of the most important processes in the changing the earth’s surface in semi-arid areas,Thus it is of great importance to study soil-erosion action.Using integrated technologies of remote sensing and geochemistry radioactivity iso-tope to extract regional soil-erosion information and to calculate quantity of soil erosion is accomplished successfully in this paper by means of beneficial experiments in the Talatan region of the Gonghe Basin,which is located in northeastern Qinghai-Tibet Pla-teau in China.The results show that the soil erosion by wind is not intensive in this region;the erosion types belong to the classes of very-soft erosion and soft-erosion type,which account for 47.12 percent and 35.58 percent,respectively,of the total study area.In total,two kinds of soil erosion account for 82.70 percent of the study area;only a small area belongs to the classes of severe erosion and very-severe erosion;this area is about 22.14 km2.Severe deposition activity has taken place in this region,and has appeared in a large area(322.67 km2),which accounts for 11.78 percent of the total study area.The results of this study show that soil erosion and deposition inventories are 870,000-1,150,000 tons and 550,000-780,000 tons,respectively,per year.The soil in-ventory shows about 320,000-370,000 tons from Talatan to Longyangxia reservoir per year.Using remote-sensing technology and 137Cs techniques is a valid means to analyze and to evaluate the quantity of soil erosion by wind in semi-arid environments.

  13. Using remote-sensing technologies in combination with Cesium-137 measurements to estimate soil-erosion quantity in semi-arid steppe areas

    Institute of Scientific and Technical Information of China (English)

    ZhanJiang Sha; HaiZhou Ma; LingQin Li; Jinzhou Du; FeiQuan Wu; QiShun Fan

    2009-01-01

    Soil erosion by wind is one of the most important processes in the changing the earth's surface in semi-arid areas, Thus it is of great importance to study soil-erosion action. Using integrated technologies of remote sensing and geochemistry radioactivity isotope to extract regional soil-erosion information and to calculate quantity of soil erosion is accomplished successfully in this paper by means of beneficial experiments in the Talatan region of the Gonghe Basin, which is located in northeastern Qinghai-Tibet Plateau in China. The results show that the soil erosion by wind is not intensive in this region; the erosion types belong to the classes of very-soft erosion and soft-erosion type, which account for 47.12 percent and 35.58 percent, respectively, of the total study area.In total, two kinds of soil erosion account for 82.70 percent of the study area; only a small area belongs to the classes of severe erosion and very-severe erosion; this area is about 22.14 km2. Severe deposition activity has taken place in this region, and has appeared in a large area (322.67 km2), which accounts for 11.78 percent of the total study area. The results of this study show that soil erosion and deposition inventories are 870,000-1,150,000 tons and 550,000-780,000 tons, respectively, per year. The soil inventory shows about 320,000-370,000 tons from Talatan to Longyangxia reservoir per year. Using remote-sensing technology and 137Cs techniques is a valid means to analyze and to evaluate the quantity of soil erosion by wind in semi-arid environments.

  14. The utilization of caesium 137 in studying soil degradation; L`utilisation du cesium 137 pour la connaissance de la degradation des sols

    Energy Technology Data Exchange (ETDEWEB)

    Wicherek, S.; Veyret, Y. [Centre de Biogeographie-Ecologie, 92 - Saint -Cloud (France); Bernard, C. [Ministere de l`Agriculture, des Pecheries et de l`Alimentation, Quebec (Canada)

    1994-12-31

    The caesium 137 isotope is distributed in the atmosphere during nuclear explosions, and is absorbed in the upper horizons of the soil on reaching the ground. When it is incorporated in the fine fraction of the soil, caesium 137 measurement allows movements affecting cultivated lands (mass movements, runoff effects, wind action) and rate of soil degradation over half a century to be evaluated. Vegetal cover and techniques of soil utilization must be considered; this method has been tested on a watershed in the Parisian Basin. 5 figs., 26 refs.

  15. The history of Cesium-137 liquid emissions by Mühleberg Nuclear Power Plant (Switzerland) is recorded in Lake Biel sediments

    Science.gov (United States)

    Girardclos, Stéphanie; Faessler, Jérôme; Loizeau, Jean-Luc; Zehringer, Markus

    2014-05-01

    Lake sediments record changes happening in their upstream river catchment and regional environment which includes traces of artificial radionuclides emissions deriving from human activities. 137Cs emissions started worldwide in the early 1950's and peaked in 1963-64 due to nuclear bomb tests in the high atmosphere. A second 137Cs activity peak, due to the 1986 Chernobyl catastrophe is recorded in sediment archives from central Europe. These two events (1963/64 and 1986) serve routinely as time markers for recent lake records. Nuclear Power Plants (NPPs) are often constructed along river course for cooling purposes. Since 1972, Mühleberg NPP (central Switzerland) lies 18 km upstream Lake Biel and releases radioactive liquid emissions into the Aare river which adds to the diffuse - above mentioned - radioactive pollution, as revealed by Albrecht et al. (1995; 1998) and recently confirmed by Thevenon et al. (2013) from Lake Biel sediments. The water of Lake Biel is used as drinking water for ca. 60'000 inhabitants and its outflowing water is further used by downstream cities lying on the Aare-Rhine course such as Basel (200'000 inhab.) In this study, the 137Cs activity curve of a 90-cm-long sediment core (BIE10-8), retrieved in April 2010 from the central Lake Biel basin at ca. 50 m depth, and measured by gamma ray spectrometry using high resolution germanium detectors, confirms previous work and reveals a new peak for the year 1998-2000, as observed by Thevenon et al. (2013). This peak is most certainly due to Mühleberg NPP as shown by the good correlation with declared 137Cs liquid emissions indicating a significant increase in 1998-99. Decay corrected activity data, converted into 137Cs fluxes, point to water pollution by Mühleberg NPP in 1975-1985 as being similar to those linked to the catastrophic events in 1963-64 and 1986 (about 75%). As former study showed that Lake Biel sediments scavenge only a portion of the total radionuclide in water, i.e. 30-55% for 60Co (Albrecht et al. 1999), our results indicate that the estimated quantities of 137Cs input infered from the sediment record correspond well to historic declared liquid emissions. Overall, this study shows how lake or reservoir sediments can be used to trace back and verify the history of past liquid emissions from nuclear power plants. In the context of the Aare and Rhine course, were radionuclide liquid emissions from four NPP add-up in the same river system until the city of Basel and also further add-up downstream in Germany, it is necessary to bring new knowledge on this subject to quantify the 35-years-long exposure through river water for drinking water and irrigation to low but repeated radioactivity. This work was financed by SNF projects on Lake Biel nr. 121666 and 146889 and gamma ray analysis by the State Laboratory of Basel-City. REFERENCES Albrecht, A., Groudsmit, G. & Zeh M. 1999: Importance of lacustrine physical factors for the distribution of anthropogenic 60Co in Lake Biel. Limnol. Oceanogr., 44, 196-206. Albrecht ,A., Reichert, P., Beer, J. & Lück A. 1995: Evaluation of the importance of reservoir sediments as sinks for reactor-derived radionuclides in riverine systems. Journal of Environmental Radioactivity, 28, 239-269. Albrecht, A., Reiser, R., Lück, A., Stoll, J.-M.A. & Giger W. 1998. Radiocesium dating of sediments from lakes and reservoirs of different hydrological regimes. Environmental Science & Technology, 1882-1887. Thevenon, F., Wirth, S.B., Fujak, M., Poté, J. & Girardclos S. 2013. Human impact on the transport of terrigenous and anthropogenic elements to peri-alpine lakes (Switzerland) over the last decades. Aquatic Sciences, 75, 413-424.

  16. Mechanistic interpretation of the varying selectivity of Cesium-137 and potassium uptake by radish (Raphanus sativus L.) under field conditions near Chernobyl.

    Science.gov (United States)

    Prorok, V V; Dacenko, O I; Bulavin, L A; Poperenko, L V; White, P J

    2016-02-01

    The selectivity of cation uptake by radish (Raphanus sativus L.) growing in the field near Chernobyl varies during the growth season. It is hypothesised that this is a consequence of variation in (137)Cs (Csss) and potassium (Kss) concentrations in the soil solution or the amount of dissolved potassium available to the plants. In the experiments reported here, it was observed that (1) Csss and Kss were positively correlated, (2) the selectivity for uptake of (137)Cs versus potassium (r) increased exponentially with decreasing Csss and Kss, and (3) the (137)Cs concentration, but not the potassium concentration, in plant material, increased abruptly upon the simultaneous reduction of Kss and Csss below about 10 μg ml(-1) and 6.7 Bq l(-1), respectively. It is thought that potassium enters root cells from the soil solution through constitutively-expressed, inward rectifying K(+) channels (KIRC) and K(+)/H(+)-symporters, whose abundance increases when plants become potassium-deficient. Cesium is thought to enter root cells through non-specific cation channels (NSCC) and, in plants lacking sufficient potassium, through K(+)/H(+)-symporters. It is argued that the increase in r, together with the abrupt increase (137)Cs concentration in plant tissues, when Kss and Csss decrease simultaneously cannot be attributed to competition between Cs(+) and K(+) for transport though KIRC, NSCC or K(+)/H(+)-symporters and that the most plausible explanation of these phenomena is an increase in the abundance of K(+)/H(+)-symporters in plants exhibiting incipient potassium deficiency.

  17. Caesium 137: Properties and biological effects resulting of an internal contamination;Cesium 137: proprietes et effets biologiques apres contamination interne

    Energy Technology Data Exchange (ETDEWEB)

    Lestaevel, P.; Racine, R.; Bensoussan, H.; Rouas, C.; Gueguen, Y.; Dublineau, I.; Bertho, J.M.; Gourmelon, P.; Jourdain, J.R.; Souidi, M. [Institut de Radioprotection et de Surete Nucleaire, IRSN, laboratoire de radiotoxicologie experimentale, direction de la radioprotection de l' homme, 92 - Fontenay-aux-Roses (France)

    2010-02-15

    Caesium-137 ({sup 137}Cs) is a radionuclide present in the environment mainly as the result of the atmospheric nuclear weapons testing and accidents arising in nuclear power plants like the Chernobyl accident in 1986. Nowadays, the health consequences resulting from a chronic exposure to this radionuclide remain unknown. After absorption, the caesium is distributed relatively homogeneously within the body, with a more important load in children than in adults. The toxicity of {sup 137}Cs is mainly due to its radiological properties. A high dose of {sup 137}Cs is responsible for a medullar dystrophy, disorders of the reproductive function, and effects on liver and renal functions. Disorders of bone mineralization and brain damages were also described in human beings. At lowest dose, {sup 137}Cs induces disturbances of wakefulness-sleep cycle, but not accompanied with behavioural disorders. The cardiovascular system was also perturbed. Biological effects of {sup 137}Cs on the metabolisms of the vitamin D, cholesterol and steroid hormones were described, but do not lead to clinical symptoms. In human beings, {sup 137}Cs leads to an immune deficiency, congenital and foetal deformations, an increased of thyroid cancer, as well as neurological disorders. It seems that children are more sensitive to the toxic effects of caesium than the adults. At present, the only effective treatment for the decorporation of the ingested {sup 137}Cs is the Prussian Blue (Radiogardase). The use of pectin to de-corporate the ingested {sup 137}Cs, in children notably, is sometimes proposed, but its administration still remains an open question. To conclude, the available scientific data suggest that {sup 137}Cs could affect a number of physiological and metabolic functions and consequently, could participate in the health risks associated to the presence of other contaminants in the environment. (authors)

  18. Standard test method for determining the content of cesium-137 in irradiated nuclear fuels by high-resolution gamma-ray spectral analysis

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2008-01-01

    1.1 This test method covers the determination of the number of atoms of 137Cs in aqueous solutions of irradiated uranium and plutonium nuclear fuel. When combined with a method for determining the initial number of fissile atoms in the fuel, the results of this analysis allows atom percent fission (burn-up) to be calculated (1). The determination of atom percent fission, uranium and plutonium concentrations, and isotopic abundances are covered in Test Methods E 267 and E 321. 1.2 137Cs is not suitable as a fission monitor for samples that may have lost cesium during reactor operation. For example, a large temperature gradient enhances 137Cs migration from the fuel region to cooler regions such as the radial fuel-clad gap, or, to a lesser extent, towards the axial fuel end. 1.3 A nonuniform 137Cs distribution should alert the analyst to the potential loss of the fission product nuclide. The 137Cs distribution may be ascertained by an axial gamma-ray scan of the fuel element to be assayed. In a mixed-oxide fu...

  19. 76 FR 40352 - National Nuclear Security Administration; Amended Record of Decision: Site-Wide Environmental...

    Science.gov (United States)

    2011-07-08

    .... These contain cobalt-60, cesium-137, radium-226, or strontium-90. OSRP may recover sources from... sealed sources is approximately 78 millirem to an individual crewmember, which equates to a fatal cancer...,000 of a latent cancer fatality among the crew. For other transportation scenarios, this...

  20. End of Life Decisions for Sealed Radioactive Sources

    Energy Technology Data Exchange (ETDEWEB)

    Pryor, Kathryn H.

    2016-02-29

    Sealed radioactive sources are encountered in a wide variety of settings – from household smoke detectors and instrument check sources, through fixed industrial gauges, industrial radiography and well logging sources, to irradiators and medical teletherapy devices. In general, the higher the level of activity in the sealed source, the stricter the regulatory control that is applied to its use, control and ultimate disposition. Lower levels of attention and oversight can and do lead to sources ending up in the wrong place – as orphan sources in uncontrolled storage, disposed in a sanitary landfill, melted down in metal recycling operations and incorporated into consumer products, or handled by an unsuspecting member of the public. There are a range of issues that contribute to the problem of improper disposal of sealed sources, and, in particular, to disused source disposal. General licensed sources and devices are particularly at risk of being disposed incorrectly. Higher activity general licensed sources, although required to be registered with the Nuclear Regulatory Commission (NRC) or Agreement State, receive limited regulatory oversight and are not tracked on a national scale. Users frequently do not consider the full life-cycle costs when procuring sources or devices and discover that they cannot afford to package, transport and dispose of their sources properly. The NRC requirements for decommissioning funding plans and financial assurance are not adequate to cover sealed source transport and disposal costs fully. While there are regulatory limits for storage of disused sources, enforcement is limited and there is no financial incentive for owners to dispose of the sources. In some cases, the lack of availability of approved Department of Transportation (DOT) Type B shipping casks also presents a barrier to sealed source disposal. The report of the Disused Sources Working Group does an excellent job of framing these issues. This article reviews both the

  1. Development of a system to verify the programs used for planning of photon beams teletherapy; Desenvolvimento de um sistema para verificar os programas utilizados nos planejamentos em teleterapia com feixes de fotons

    Energy Technology Data Exchange (ETDEWEB)

    Ocariz Ayala, Victor Daniel

    2004-12-15

    The main objective of radiotherapy is to deliver to the tumor the radiation dose prescribed by the physician, in the most possible accurate form, to save, as much as possible, the healthy tissues located in the neighborhood of the tumor. In order to reach these objectives, it is necessary to carry out a treatment planning and the more the used technologies and therapeutical procedures are sophisticated, the more the planning will be sophisticated. The most sophisticated planning systems use computer programs and are able to determine dose distributions in three dimensions. However, since they work using mathematical models, they may fail and it is necessary to evaluate their performances in order to be considered reliable. Therefore, the availability of a system capable to evaluate the performance of planning systems employed in oncological teletherapy, using ionizing radiation, becomes important. In this work, a data file to be used in radiotherapy planning system quality control (Algorithm accuracy and dose distribution) was developed and it is able to be sent by mail to the radiotherapy services that work with photon beams. (author)

  2. The search for geologic evidence of distant-source tsunamis using new field data in California: Chapter C in The SAFRR (Science Application for Risk Reduction) Tsunami Scenario

    Science.gov (United States)

    Wilson, Rick; Hemphill-Haley, Eileen; Jaffe, Bruce; Richmond, Bruce; Peters, Robert; Graehl, Nick; Kelsey, Harvey; Leeper, Robert; Watt, Steve; McGann, Mary; Hoirup, Don F.; Chagué-Goff, Catherine; Goff, James; Caldwell, Dylan; Loofbourrow, Casey

    2014-01-01

    A statewide assessment for geological evidence of tsunamis, primarily from distant-source events, found tsunami deposits at several locations, though evidence was absent at most locations evaluated. Several historical distant-source tsunamis, including the 1946 Aleutian, 1960 Chile, and 1964 Alaska events, caused inundation along portions of the northern and central California coast. Recent numerical tsunami modeling results identify the eastern Aleutian Islands subduction zone as the “worstcase” distant-source region, with the potential for causing tsunami runups of 7–10 m in northern and central California and 3–4 m in southern California. These model results, along with a review of historical topographic maps and past geotechnical evaluations, guided site selection for tsunami deposit surveys. A reconnaissance of 20 coastal marshlands was performed through site visits and coring of shallow surface sediments to determine if evidence for past tsunamis existed. Although conclusive evidence of tsunami deposits was not found at most of the sites evaluated, geologic evidence consistent with tsunami inundation was found at two locations: Three marshes in the Crescent City area and Pillar Point marsh near Half Moon Bay. Potential tsunami deposits were also evaluated at the Carpinteria Salt Marsh Reserve in Santa Barbara County. In Crescent City, deposits were ascribed to tsunamis on the basis of stratigraphic architecture, particle size, and microfossil content, and they were further assigned to the 1964 Alaska and 1700 Cascadia tsunamis on the basis of dating by cesium-137 and radiocarbon methods, respectively. The 1946 tsunami sand deposit was clearly identified throughout Pillar Point marsh, and one to two other similar but highly discontinuous sand layers were present within 0.5 m of the surface. A tsunami-origin interpretation for sand layers at Carpinteria is merely consistent with graded bedding and unsupported by diatom or foraminiferal assemblages

  3. In vivo effects of a chronic contamination by uranium or cesium 137 on the pharmaceutical metabolism, of the vitamin D and cholesterol; Effets in vivo d'une contamination chronique par l'uranium ou le cesium 137 sur le metabolisme du medicament, de la vitamine D et du cholesterol

    Energy Technology Data Exchange (ETDEWEB)

    Souidi, M

    2006-11-15

    In conclusion, an animal model, miming the chronic contamination of the populations exposed to the uranium, was used for the first time to show that the chronic ingestion of a weak dose of depleted uranium can affect the level of active vitamin D without modifying the mineral homeostasis. This study shows that this radionuclide can lead molecular modifications of the CYPs and the nuclear receivers involved in the metabolism of the vitamin D not only at the level of the liver and kidney but also at the level of the independent metabolism in the brain. The deficiency in vitamin D can provoke osseous diseases such as the rickets at the child and the osteomalacia at the adult. The three categories of population the most exposed to this deficiency are the infants, the pregnant women and the old persons. Strong prevalence of the vitamin D deficiency associated with a chronic exposure to uranium could lead to osseous disorders. To verify this hypothesis, it will be necessary secondly to realize this study on individuals animal models predisposed to the rickets or to the osteomalacia. (N.C.)

  4. Simulation of radiation transport using MCNP for a teletherapy machine; Simulacion del transporte de radiacion usando MCNP para una maquina de teleterapia

    Energy Technology Data Exchange (ETDEWEB)

    Flores O, F.E.; Mireles G, F.; Davila R, J.I.; Pinedo V, J.L.; Risorios M, C.; Lopez del Rio, H. [UAZ, Unidad Academica de Estudios Nucleares, 98068 Zacatecas (Mexico)

    2008-07-01

    The MCNP code is used to simulate the radiation transport taking as tools the transport physics of each particle, either photon, neutron or electron, and the generation of random numbers. Developed in the Los Alamos National Laboratory, this code has been used thoroughly with great success, because the results of the simulations are broadly validated with representative experiments. In the one present work the room of radiotherapy of the Institute Zacatecano of the Tumor it is simulated, located in the city of Zacatecas where one is Theratron 780C machine manufactured by MSD Nordion, with the purpose of estimating the contribution to the dose that would be received in different points of the structure, included three directly under the source. Three results of analytical calculations for points located at different distances from the source are presented, and they are compared against those obtained by the simulation. Its are also presented results for the simulation of 10 points more distributed around the source. (Author)

  5. Assessment on security system of radioactive sources used in hospitals of Thailand

    Energy Technology Data Exchange (ETDEWEB)

    Jitbanjong, Petchara, E-mail: petcharajit@gmail.com; Wongsawaeng, Doonyapong [Nuclear Engineering Department, Faculty of Engineering, Chulalongkorn University, 254 Phayathai Road, Pathumwan, Bangkok 10330 (Thailand)

    2016-01-22

    Unsecured radioactive sources have caused deaths and serious injuries in many parts of the world. In Thailand, there are 17 hospitals that use teletherapy with cobalt-60 radioactive sources. They need to be secured in order to prevent unauthorized removal, sabotage and terrorists from using such materials in a radiological weapon. The security system of radioactive sources in Thailand is regulated by the Office of Atoms for Peace in compliance with Global Threat Reduction Initiative (GTRI), U.S. DOE, which has started to be implemented since 2010. This study aims to perform an assessment on the security system of radioactive sources used in hospitals in Thailand and the results can be used as a recommended baseline data for development or improvement of hospitals on the security system of a radioactive source at a national regulatory level and policy level. Results from questionnaires reveal that in 11 out of 17 hospitals (64.70%), there were a few differences in conditions of hospitals using radioactive sources with installation of the security system and those without installation of the security system. Also, personals working with radioactive sources did not clearly understand the nuclear security law. Thus, government organizations should be encouraged to arrange trainings on nuclear security to increase the level of understanding. In the future, it is recommended that the responsible government organization issues a minimum requirement of nuclear security for every medical facility using radioactive sources.

  6. Radiological Conditions on Rongelap Atoll: Diving and Fishing on and Around Rongelap Atoll

    Energy Technology Data Exchange (ETDEWEB)

    Hamilton, T F

    2003-02-01

    resettlement workers living on Rongelap Island to check the amount of cesium-137 in their bodies. The amount of cesium-137 detected in resettlement workers living on Rongelap Island over the past three years is well below the level of radiation exposure considered safe by the Nuclear Claims Tribunal. Returning residents and visitors to Rongelap will also be able to receive a whole body count free of charge to check the level of cesium in their bodies. There is also a very low health risk from exposure to external sources of radiation from visiting or walking around any of the islands on the atoll.

  7. Partial breast radiotherapy with simple teletherapy techniques

    Energy Technology Data Exchange (ETDEWEB)

    Fekete, Gábor; Újhidy, Dóra; Együd, Zsófia; Kiscsatári, Laura; Marosi, Gusztáv; Kahán, Zsuzsanna; Varga, Zoltán, E-mail: varga.zoltan@med.u-szeged.hu

    2015-01-01

    A prospective pilot study of partial breast irradiation (PBI) with conventional vs hypofractionated schedules was set out. The study aimed to determine efficacy, acute and late side effects, and the preference of photon vs electron irradiation based on individual features. Patients were enrolled according to internationally accepted guidelines on PBI. Conformal radiotherapy plans were generated with both photon and electron beams, and the preferred technique based on dose homogeneity and the radiation exposure of healthy tissues was applied. For electron dose verification, a special phantom was constructed. Patients were randomized for fractionation schedules of 25 × 2 vs 13 × 3 Gy. Skin and breast changes were registered at the time of and ≥1 year after the completion of radiotherapy. Dose homogeneity was better with photons. If the tumor bed was located in the inner quadrants, electron beam gave superior results regarding conformity and sparing of organ at risk (OAR). If the tumor was situated in the lateral quadrants, conformity was better with photons. A depth of the tumor bed ≥3.0 cm predicted the superiority of photon irradiation (odds ratio [OR] = 23.6, 95% CI: 5.2 to 107.5, p < 0.001) with >90% sensitivity and specificity. After a median follow-up of 39 months, among 72 irradiated cases, 1 local relapse out of the tumor bed was detected. Acute radiodermatitis of grade I to II, hyperpigmentation, and telangiectasia developed ≥1 year after radiotherapy, exclusively after electron beam radiotherapy. The choice of electrons or photons for PBI should be based on tumor bed location; the used methods are efficient and feasible.

  8. Partial breast radiotherapy with simple teletherapy techniques.

    Science.gov (United States)

    Fekete, Gábor; Újhidy, Dóra; Együd, Zsófia; Kiscsatári, Laura; Marosi, Gusztáv; Kahán, Zsuzsanna; Varga, Zoltán

    2015-01-01

    A prospective pilot study of partial breast irradiation (PBI) with conventional vs hypofractionated schedules was set out. The study aimed to determine efficacy, acute and late side effects, and the preference of photon vs electron irradiation based on individual features. Patients were enrolled according to internationally accepted guidelines on PBI. Conformal radiotherapy plans were generated with both photon and electron beams, and the preferred technique based on dose homogeneity and the radiation exposure of healthy tissues was applied. For electron dose verification, a special phantom was constructed. Patients were randomized for fractionation schedules of 25 × 2 vs 13 × 3Gy. Skin and breast changes were registered at the time of and ≥1 year after the completion of radiotherapy. Dose homogeneity was better with photons. If the tumor bed was located in the inner quadrants, electron beam gave superior results regarding conformity and sparing of organ at risk (OAR). If the tumor was situated in the lateral quadrants, conformity was better with photons. A depth of the tumor bed ≥3.0cm predicted the superiority of photon irradiation (odds ratio [OR] = 23.6, 95% CI: 5.2 to 107.5, p 90% sensitivity and specificity. After a median follow-up of 39 months, among 72 irradiated cases, 1 local relapse out of the tumor bed was detected. Acute radiodermatitis of grade I to II, hyperpigmentation, and telangiectasia developed ≥1 year after radiotherapy, exclusively after electron beam radiotherapy. The choice of electrons or photons for PBI should be based on tumor bed location; the used methods are efficient and feasible.

  9. Transcendental Terrorism and Dirty Bombs: Radiological Weapons Threat Revisited

    Science.gov (United States)

    2006-02-01

    radioactive sources. This gap sets the stage for a Goiania -type disaster, where thieves in Brazil searching for scrap metal broke into an abandoned cancer...unknowingly and unwittingly spread the contamination throughout Goiania .53 The results were five deaths, 151 people who suffered internal...for obsolete radioactive materials. While the distribution of cesium-137 in Goiania was not the result of deliberate terrorist action, it certainly

  10. Hunting a Black Swan: Policy Options for America’s Police in Preventing Radiological/Nuclear Terrorism

    Science.gov (United States)

    2012-09-01

    interesting case to examine in the discussion of RDDs involves an incident from Goiania , Brazil in 1987 where a Cesium 137 source was removed from an...exposure.118 Goiania is often cited as an example for RDD planning. The effects of a deliberate dispersal would obviously be several orders of...magnified through notification to the media to raise public alarm and concern. In the Goiania incident described above, once it became public knowledge that

  11. Investigations into the transfer of cesium 137 and strontium 90 in selected exposure pathways. Final report; Untersuchungen ueber den Transfer von Caesium 137 und Strontium 90 in ausgewaehlten Belastungspfaden. Abschlussbericht

    Energy Technology Data Exchange (ETDEWEB)

    Roemmelt, R.; Hiersche, L.; Wirth, E.

    1991-12-01

    This research project investigates the behaviour of radiocesium and strontium 90 in natural conifer forest sites and derives corresponding transfer factors for radioecological calculations. As a point of particular interest the question was investigated in how far the requirements of the different mushroom species and the properties of the forest soil bear on the dynamics and transfer rate of radiocesium and strontium 90. To complement the investigations, autotrophic plants were included. The results of these studies are compared with the behaviour of the same radionuclides on farmland. The differences are discussed. (orig./HP). [Deutsch] Im Forschungsvorhaben wurde das Verhalten von Radiocaesium und Strontium 90 in den natuerlichen Nadelstandorten untersucht und entsprechende Transferfaktoren fuer radiooekologische Berechnungen abgeleitet. Besondere Aufmerksamkeit galt der Frage, inwieweit die Lebensweise der verschiedenen Pilzspezies und die Waldbodeneigenschaften die Dynamik und die Transferrate von Radiocaesium und Strontium 90 beeinflussen. Als Ergaenzung wurden autotrophe Pflanzen in die Untersuchungen einbezogen. Die Ergebnisse dieser Untersuchungen werden mit dem Verhalten dieser Radionuklide auf landwirtschaftlich genutzten Flaechen verglichen und die Unterschiede diskutiert. (orig./HP).

  12. In-vivo determination of strontium 90 and cesium 137 in exposed persons in the Tscheljabinsk region (southern Ural); In-vivo-Bestimmung von Strontium 90 und Caesium 137 an exponierten Personen in der Region Tscheljabinsk (Suedural)

    Energy Technology Data Exchange (ETDEWEB)

    Schoeffmann, E. [Bayerisches Landesamt fuer Umweltschutz, Muenchen (Germany). Referat Betrieb der LfU-Messnetzzentrale; Zeising, H. [Bayerisches Landesamt fuer Umweltschutz, Muenchen (Germany). Referat Radioaktivitaetsmesswesen

    1994-12-31

    While the Russians have been busy for decades determining the doses received by, and resulting health effects to, the concerned population - which falls into three groups: (a) workers at the Majak plutonium factory, (b) the population along the Techa river, and (c) the population from the area contaminated by the Kyschtym accident - it is also true that the integral strontium 90 exposure has been, and is being, determined subsequently via whole-body bremsstrahlung measurement (both on the part of the Russians and as a German scheme in 1993). In accordance with what was indicated by the Russian side, the Majak workers were found to have a distinctly higher risk of cancer. The population along the Techa river, too, with an average dose of 0.4 Gy for the red bone marrow, showed a significant increase in the rate of leukemia. By contrast, the persons affected by the Kyschtym accident, with a distinctly lower mean dose of about 0.02 Gy, so far have not shown any long-term effects.- As yet no exact quantitative statement regarding the cancer risks can be made, for two reasons: the comprehensive data material collected by the Russians has not yet been sufficiently evaluated, and suitable control persons need yet to be found. (orig./HP) [Deutsch] An einer Bestimmung der Dosen und der daraus resultierenden gesundheitlichen Effekte der betroffenen Bevoelkerung - naemlich der drei Gruppen (a) Arbeiter der Plutoniumfabrik Majak, (b) die Bevoelkerung entlang des Flusses Techa und (c) die Bevoelkerung aus dem durch den Kyschtym-Unfall kontaminierten Gebiet, wird zwar von russischer Seite seit Jahrzehnten gearbeitet, aber die integrale Sr 90-Exposition wurde und wird nachtraeglich ueber die Messung von Bremsstrahlung im Ganzkoerper (neben russischer Messung auch die deutsche Messaktion im Jahre 1993) bestimmt. Wie von russischer Seite angegeben, fand sich bei den Majak-Arbeitern eine deutliche Erhoehung des Krebsrisikos, ebenso wurde bei der Bevoelkerungsgruppe entlang des Flusses Techa mit einer durchschnittlichen Dosis von 0,4 Gy fuer das rote Knochenmark eine signifikante Erhoehung der Leukaemierate festgestellt. Bei den durch den Kyschtym-Unfall betroffenen Personen mit einer deutlich niedrigeren mittleren Dosis von ca. 0,02 Gy wurden bisher dagegen keine Langzeiteffekte festgestellt. Eine genaue quantitative Aussage zu den Krebsrisiken kann vorerst noch nicht gegeben werden, da zum einen das von russischer Seite gesammelte umfangreiche Datenmaterial noch nicht ausreichend ausgewertet ist und zum anderen noch geeignete Kontrollpersonen gefunden werden muessen. (orig./HP)

  13. Some thoughts on the compliance with intervention levels in an area contaminated by an accidental deposition of caesium 137; Reflexions sur le respect des niveaux d`intervention dans un territoire contamine par un depot accidentel de cesium 137

    Energy Technology Data Exchange (ETDEWEB)

    Maubert, H.; Robeau, D.; Renaud, P. [CEA Centre d`Etudes de Cadarache, 13 - Saint-Paul-lez-Durance (France); Linge, I.; Pavlovski, O.; Ossipiants, I. [Institut de Surete Nucleaire, Moscou (Russian Federation)

    1995-10-01

    After a nuclear accident leading to an important radionuclide deposition, the responsible authorities are faced to the question of complying with intervention levels. These regulations may be expressed as mass activities in foodstuffs, or individual doses for the populations. A situation of acute caesium 137 contamination of the environment was played in 1993 during a French and Russian joint crisis exercise. In answering the questions from the administration, the experts examined the conditions allowing agricultural practices (1) according to a set of intervention levels in foodstuffs, and (2) how that was compatible with a recommendation relative to an individual dose for the populations of 1 mSv/y, although this limit is applicable in normal conditions and is not intended for post-accidental situations. (authors). 9 refs., 2 figs., 3 tabs.

  14. Evolution of caesium 137 levels in coconut water and copra in french Polynesia, since 1967. Evolution de la teneur en cesium 137 depuis 1967 dans l'eau de coco et le coprah en Polynesie francaise

    Energy Technology Data Exchange (ETDEWEB)

    Kabis de Saint-Chamas, L.; Bablet, J.P.; Ducousso, R. (Service mixte de controle biologique, 91 - Montlhery (FR)); Arnould, C. (Laboratoire d' etude et de surveillance de l' environnement, Papeete (FR))

    1991-01-01

    Nuclear experiments have been carried out by France in french Polynesia since 1966. The tests were first atmospheric, they have been underground since 1975. The experiment monitoring programme includes monitoring of {sup 137}Cs contents in coconuts from the whole french polynesian territory. The methodology is described and the results of the 2 589 samples collected for 1967 to 1988 are presented. The maximum content found since 1967 is 52 Bq.kg{sup -1} for coconut water and 289 Bq.kg{sup -1} for coconut copra. The decrease of {sup 137}Cs content is constant without discontinuity, whatever the distance from the explosion sites. The committed dose equivalent from {sup 137}Cs delivered by coconut water and copra consumption represents only a few microsieverts a year.

  15. The great fear of 1987: a rereading of the accident with Cesium-137 in Goiania, Brazil; O grande medo de 1987: uma releitura do acidente com o Cesio-137 em Goiania

    Energy Technology Data Exchange (ETDEWEB)

    Oliveira Junior, Euripedes Monteiro de

    2016-11-01

    The works that take as object of study the radioactive accident in Goiania, and I have found to date, have tried to give special importance to its legal, psychosocial and clinical trials of radiation patients. Here in this text, I will try to understand this event from its historical dimension of fear, emphasizing its historicity from the social and cultural practices of some people, groups and entities involved with the issue. In other words, the focus of this study will be in the memories of those social relations that have been built while unfolding the event, both past and present. In this sense, we find our main concerns contained in a number of issues that are constantly alluded to discussions in which the central concepts refer to the event, memory and narrative in this case will be worked out by building the fear contained in people's memories, in groups involved in the event as well as the narratives constructed by official agencies involved in the event along with the film and the news media. (author)

  16. Experimental contamination of margaritana margaritifera (L) (a Fresh water bivalve) by caesium 137; Contamination experimentale de margaritana margaritifera (L) (bivalve d'eau douce) par le cesium 137

    Energy Technology Data Exchange (ETDEWEB)

    Foulquier, L.; Bovard, P.; Grauby, A. [Commissariat a l' Energie Atomique, Cadarache (France). Centre d' Etudes Nucleaires

    1966-07-01

    The hydro biological research carried out in the Radio-Ecology Section has led the authors to study some Margaritana sampling stations situated down-stream from the Monts d'Arree nuclear power station. They describe the preservation and contamination methods used for fixing the {sup 137}Cs concentration factors in the case of Margaritana Margaritifera (L). The results of experiments carried out over a period of one hundred days show that the specific activity of the various organs is stabilized after thirty to thirty-five days. The authors have noticed a relatively low adsorption on the shell through the intermediary of micro-organisms, and a strong and rapid absorption in the soft parts. The concentration factors have values, at equilibrium, of around: 9 for the shell, 300 for all the organs, and 38 for the whole animal. A comparison of these results with work published by other authors makes it possible to draw general conclusions concerning the mechanism of {sup 137}Cs fixation by lamellibranch, as well as their capacity of fixation. (author) [French] Les etudes hydrobiologiques effectuees au sein de la Section de Radio-Ecologie ont amene les auteurs a etudier des stations de prelevement de Margaritana en aval de la Centrale Nucleaire des Monts d'Arree. Ils decrivent les methodes de conservation et de contamination utilisees pour l'etablissement des facteurs de concentration du {sup 137}Cs par Margaritana margaritifera (L). Les resultats des experimentations menees pendant cent jours montrent que les activites specifiques de la coquille et des differents organes se stabilisent au bout de trente a trente-cinq jours. Les auteurs constatent une adsorption relativement faible sur la coquille par l'intermediaire des micro-organismes et une absorption forte et rapide dans les parties molles. Les facteurs de concentration se situent, a l'equilibre, autour de: 9 pour la coquille, 300 pour l'ensemble des organes et 38 si l'on considere l'animal total. Cette etude comparee a celles deja effectuees par d'autres auteurs permet de degager des idees generales sur le mode et la capacite de fixation du {sup 137}Cs par les lamellibranches. (auteur)

  17. Monitoring of caesium-137 in food plants and muscle from moose, red deer and wild reindeer in 2010.; Overvaaking av cesium-137 i beitevekster og kjoett av elg, hjort og villrein i 2010.

    Energy Technology Data Exchange (ETDEWEB)

    Veiberg, Vebjoern; Gaare, Eldar; Stokke, Sigbjoern; Solberg, Erling J.; Skuterud, Lavrans

    2011-07-01

    The monitoring of Cs-137 fall-out from the Chernobyl accident in 1986, started the same year. Several plants and wild reindeer in natural ecosystems in Nord-Rondane have been followed annually ever since. Four more wild reindeer ranges were included in 2001: Setesdal-Ryfylkeheiene, Hardangervidda, Nord-Ottadalen, Snoehetta and Nord-Rondane. From 2007 Forollhogna was also included. On fixed plots in Nord-Rondane and Snoehetta some of the reindeer forage plants, including both higher plants and fruticose lichens, have been sampled and analyzed annually since 1986. This was also done in 2010. In addition plants and lichens were sampled at five locations along an altitudinal gradient at Soendre Knutshoe, and at 7-8 locations along an east-west gradient from Kollaflata to Skarhoe in the Jora valley continuing along the Aursjoe to Torbudalen. All these locations were sampled annually between 1987-1990, but they have not been sampled since. In 2010 samples from red deer and moose was also collected from eight different regions located within the following counties: Oppland, Telemark, Vest-Agder, Rogaland, Sogn and Fjordane, Nord-Troendelag, Nordland and Troms. Red deer were sampled in four regions and moose in six. Both species were sampled in Oppland. In 2010 76, 49 and 61 samples were collected from wild reindeer, red deer and moose respectively. All measures of caesium levels were performed on dried samples. For the 596 samples of plants and lichen the results refer to caesium-levels in dried samples. For the meat samples, results refer to caesium-137 levels in raw meat. Due to large variation in measured levels of caesium within species and sampling area, we give median values instead of mean values.The highest caesium levels in wild reindeer were found in Snoehetta (1010 Bq/kg) and Nord-Rondane (2686 Bq/kg). The levels found in the other areas were considerably lower. The highest caesium levels in both red deer (Sel, 677 Bq/kg) and moose (Vaaga, 365 Bq/kg) were found in Oppland. For all three species we found large variation in the measured levels of caesium within each sampling area. This was particularly evident in the areas with the highest caesium levels. This is most likely caused by a locally heterogeneous distribution of caesium, and reflects that the individual's home range location has a large influence on their exposure. Time of shooting and choice of food plants may also have large influence on the levels of caesium found, since some plants contain higher levels of caesium than others. Several species of fungus are such examples, and variation in availability of fungi can cause significant differences in caesium ingestion in herbivores. The overall picture was still in accordance with the expectations based on information about the geographic distribution of the fall-out. None of the measured meat samples exceeded the advisory limit for venison (3000 Bq/kg) determined by the Norwegian Radiation Protection Authority. Most of the autumn food plants like bilberry (Vaccinium myrtillus), crowberry (Empetrum nigrum), wavy hair-grass (Avenella flexuosa) and dwarf birch (Betula nana) produce litter that is decomposed and taken up by the roots. These species showed large variation in caesium content between locations. As an example bilberry was measured to 3200 Bq/kg at a location in Rondane, whereas an equivalent sample from Torbudalen in Snoehetta measured 1200 Bq/kg. Overall these species now measure between 200 and 600 Bq/kg dry weight in Nord-Rondane and Knutshoe. The half-life of caesium in these plants are now between 27 and 47 years. This is approximately equal to, or considerably longer than the half-life of Cs-137 of 30.1 years. Heather, although in short supply in this environment, is an interesting exception and was measured to 3300 Bq/kg in 2010. It shows little change over time, and may even have increased in Cs-137 level. Six fruticose lichens from the Dovrefjell, Groenbakken sampling station, show from 300 to 2000 Bq/kg today. Compared with higher plants they have a shorter half-life, 4.5 to 6 years. The same species in Nord-Rondane have 500-1000 Bq/kg.The data series for wild reindeer in Nord-Rondane is almost continuous from 1986 to 2010. In the period 1986-1996 the biological half-life of the Cs-137 content was 4 years, whereas the half-life for the whole period is 8 years. The traces from the Chernobyl accident will therefore still be measurable in our terrestrial ecosystems for many years to come. (Author)

  18. Airborne mapping of radioactive contamination. Results from a test in Finland, RESUME95

    Energy Technology Data Exchange (ETDEWEB)

    Roenning, S.; Smethurst, M.A. [Geological Survey of Norway (Norway)

    1997-12-31

    The Geological Survey of Norway participated in the exercise RESUME95 (Rapid Environmental Surveying Using Mobile Equipment 95) in Finland, during August 1995. The purpose of the exercise was to 1) test preparedness in the Nordic countries for accidents involving the release and dispersal of radioactive material, 2) compare results from the different teams participating in the exercise, 3) establish routines for the exchange of data and 4) investigate the possibility of international assistance in the event of nuclear accidents. The Geological Survey of Norway carried out a survey over three test areas (area I, II and III). All three areas were contaminated with man made radionuclides in the days following the Chernobyl nuclear reactor accident. The Cesium-137 contamination level was reported to be about 50 kBq/m{sup 2} in area I, and this area was used for calibration. In area II mapping of Cesium-137 ground concentration was carried out. Detection of hidden artificial radiation sources were the main purpose in area III. This report describes the exercise - RESUME95, field operations, calibration, mapping of Cesium-137 ground concentration and detection of hidden point sources. Results are presented as colour maps. (au).

  19. Radiocesium concentrations in two populations of naturally contaminated feral hogs (Sus scrofa domesticus). [/sup 137/Cs

    Energy Technology Data Exchange (ETDEWEB)

    Stribling, H.L.

    1978-12-01

    Two populations of feral hogs (Sus scrofa domesticus) were studied during the summer and winter seasons from 1976 to 1978 in order to determine concentrations, distributional patterns, and predictability of cesium-137 in the whole body and various body compartments of these animals. One population inhabited the Savannah River Plant (SRP) Aiken, South Carolina, an area contaminated by reactor waste and natural fallout; the other inhabited Ossabaw Island (OI), Georgia, an area contaminated by natural fallout alone. Whole-body burdens on the SRP averaged about 2 and about 1.5 times higher than those samples on OI during the summer and winter seasons, respectively. Radiocesium levels in feral hogs on SRP were not only influenced by the additional source of contamination but apparently fluctuated seasonally as well since the whole-body burdens of SRP hogs sampled were about 1.5 times higher in the summer than in the winter. Levels of cesium-137 in skeletal muscle have decreased in the SRP feral hog population since 1968. On the SRP, feces best predicted whole-body burdens with an r/sup 2/ of 0.67. All internal organs examined predicted levels in skeletal muscle well for SRP animals but best predictability of muscle (R/sup 2/ = 0.94) was achieved when brain, liver, and feces were combined in a multiple regression equation. Muscle was the best predictor of cesium-137 in all body compartments.

  20. C.A.R.O.L. project - Camargue Rhone Languedoc final report; Projet Carol - Camargue Rhone Languedoc rapport final

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2006-07-01

    This report had for objective to study the dispersion of artificial radionuclides in the low Rhone valley, then to identify and to quantify the principal flux or transfers that have lead to this distribution. Atmospheric nuclear tests fallout, Chernobylsk fallout nuclear facilities in the Rhone valley are such possible sources of radionuclides in this area. The study of the origin of the cesium 137 present in soils has lead to quantify the relationship between the deposits consecutive to Chernobylsk accident and the rains of the first week of may 1986. This study has been the first step to the elaboration of a mapping of cesium 137 deposit, in the east of France in a first time then all over the France. it is the superimposition of this map with this one of atmospheric nuclear tests fallout that allows today to answer to the question of cesium 137 activity in some French areas. An other application has been the answer relative to the nuclear fallout of Chernobylsk in Corsica.. Equally, this study has allowed to answer to the questions about the quality of wine in the Rhone valley and the situation of plutonium in the flooded region of Camargue. (N.C.)

  1. Source Water Protection Contaminant Sources

    Data.gov (United States)

    Iowa State University GIS Support and Research Facility — Simplified aggregation of potential contaminant sources used for Source Water Assessment and Protection. The data is derived from IDNR, IDALS, and US EPA program...

  2. Waste Crate and Container Imaging Using the Vehicle and Cargo Inspection System. Innovative Technology Summary Report

    Energy Technology Data Exchange (ETDEWEB)

    None

    2000-07-01

    The Vehicle and Cargo Inspection System (VACIS) is a highly penetrating gamma ray imaging system that provides a means to non-invasively image crate contents prior to crate disassembly. The VACIS unit uses a 1.6 Curie collimated source (Cesium-137) aimed at a linear detector to create an image as the unit passes by the crate. In the demonstrated mobile unit, the source and detector were mounted on a boom truck. As the crate passed between the source and detector, a near real-time composite image of the contents was constructed from the linear image of the VACIS unit's on board computer and recorded on disk.

  3. Determination of the intrinsic energy dependence of LiF:Mg,Ti thermoluminescent dosimeters for {sup 125}I and {sup 103}Pd brachytherapy sources relative to {sup 60}Co

    Energy Technology Data Exchange (ETDEWEB)

    Reed, J. L., E-mail: jlreed2@wisc.edu; Micka, J. A.; Culberson, W. S.; DeWerd, L. A. [Department of Medical Physics, University of Wisconsin–Madison, Madison, Wisconsin 53705 (United States); Rasmussen, B. E. [Department of Radiation Oncology, UP Health System Marquette, 580 West College Avenue, Marquette, Michigan 49855 (United States); Davis, S. D. [Department of Medical Physics, McGill University Health Centre, Montreal General Hospital (L5-112), 1650 Cedar Avenue, Montreal, Quebec H3G 1A4 (Canada)

    2014-12-15

    Purpose: To determine the intrinsic energy dependence of LiF:Mg,Ti thermoluminescent dosimeters (TLD-100) for {sup 125}I and {sup 103}Pd brachytherapy sources relative to {sup 60}Co. Methods: LiF:Mg,Ti TLDs were irradiated with low-energy brachytherapy sources and with a {sup 60}Co teletherapy source. The brachytherapy sources measured were the Best 2301 {sup 125}I seed, the OncoSeed 6711 {sup 125}I seed, and the Best 2335 {sup 103}Pd seed. The TLD light output per measured air-kerma strength was determined for the brachytherapy source irradiations, and the TLD light output per air kerma was determined for the {sup 60}Co irradiations. Monte Carlo (MC) simulations were used to calculate the dose-to-TLD rate per air-kerma strength for the brachytherapy source irradiations and the dose to TLD per air kerma for the {sup 60}Co irradiations. The measured and MC-calculated results for all irradiations were used to determine the TLD intrinsic energy dependence for {sup 125}I and {sup 103}Pd relative to {sup 60}Co. Results: The relative TLD intrinsic energy dependences (relative to {sup 60}Co) and associated uncertainties (k = 1) were determined to be 0.883 ± 1.3%, 0.870 ± 1.4%, and 0.871 ± 1.5% for the Best 2301 seed, OncoSeed 6711 seed, and Best 2335 seed, respectively. Conclusions: The intrinsic energy dependence of TLD-100 is dependent on photon energy, exhibiting changes of 13%–15% for {sup 125}I and {sup 103}Pd sources relative to {sup 60}Co. TLD measurements of absolute dose around {sup 125}I and {sup 103}Pd brachytherapy sources should explicitly account for the relative TLD intrinsic energy dependence in order to improve dosimetric accuracy.

  4. 小型ロボットに用いるマイクロコンピュータの放射線耐久実験 : 極限下でのレスキューロボットの開発に向けて

    OpenAIRE

    大場, 公隆; 武藤, 啓太郎; 玉川, 洋一; 平田, 隆幸

    2008-01-01

    The damage tests of microprocessors were carried out under γ-rays. The PIC microprocessors produced by Microchip Technology Inc are inexpensive and popular CPU. so that they are used in autonomous small robots.Under γ-rays,we tested the reliability of the PIC12F675 and PIC16F84A that belonged to mid-renge of the 8-bit PIC microprocessor's family. The source of γ-rays was Cesium 137.The source of γ-rays was mounted on the PIC directly.The PIC's plastic package was scraped by 0.7 mm in order to...

  5. Prevention of skin reactions due to teletherapy in women with breast cancer: a comprehensive review Prevención de las reacciones en la piel debido a teleterapia en mujeres con cáncer de mama: revisión integradora Prevenção de reações de pele devido à teleterapia em mulheres com câncer de mama: revisão integrativa

    Directory of Open Access Journals (Sweden)

    Marceila de Andrade

    2012-06-01

    Full Text Available One of the possible courses of cancer treatment is teletherapy, and one of the most important adverse side effects are skin reactions, an ailment more commonly called radiodermatitis. The main purpose of this study is to analyze knowledge of the evidence about topical products used in the prevention of radiodermatitis, to support care delivery to women with breast cancer during teletherapy. The research method used here is the comprehensive literature review. Four databases were used to select the bibliography. The sample consists of 15 articles. The data shows that, among the topical products analyzed here, Calendula, corticosteroids and Xclair have shown significant protective effects, underlining their actions. The lack of articles published in Brazil highlights the need for further research in this area, seeking better care quality through the use of products with scientifically proven efficiency.Teleterapia está entre las modalidades de tratamiento para el cáncer y uno de sus principales efectos adversos son reacciones de la piel, comúnmente llamado radiodermatitis. Este estudio objetivó analizar el conocimiento acerca de los productos tópicos utilizados para la prevención de la radiodermatitis que justifiquen la atención en teleterapia en mujeres con cáncer de mama. Se adoptó como método de investigación la revisión integradora de la literatura. Para la selección de los artículos se utilizaron cuatro bases de datos. La muestra fue constituida por 15 artículos. Los datos muestran que entre los productos tópicos analizados la caléndula, esteroides y Clair X tuvo un efecto protector significativo, destacando así por sus acciones. La ausencia de artículos publicados en Brasil se centra en la necesidad de seguir investigando para mejorar la calidad de la atención mediante el uso de productos con una eficacia científicamente probada.Dentre as modalidades de tratamento para o câncer está a teleterapia, e um dos principais

  6. Crowd Sourcing.

    Science.gov (United States)

    Baum, Neil

    2016-01-01

    The Internet has contributed new words and slang to our daily vernacular. A few terms, such as tweeting, texting, sexting, blogging, and googling, have become common in most vocabularies and in many languages, and are now included in the dictionary. A new buzzword making the rounds in industry is crowd sourcing, which involves outsourcing an activity, task, or problem by sending it to people or groups outside a business or a practice. Crowd sourcing allows doctors and practices to tap the wisdom of many instead of relying only on the few members of their close-knit group. This article defines "crowd sourcing," offers examples, and explains how to get started with this approach that can increase your ability to finish a task or solve problems that you don't have the time or expertise to accomplish.

  7. Wholebody Radiation Counting System.

    Science.gov (United States)

    1985-05-01

    curves shown are for a Cesium 137 source and show that the OPAMP is achieving the multiplication of forty and that it is being operated in the non...voltage in the range of one to three volts. This was accomplished by using a Fairchild uA715 operational amplifier ( OPAMP ). This unit was selected...for its ability to operate at very high rates with little distortion. The Fairchild OPAMP has a slew rate of 400 volts per microsecond and the ability

  8. Fracture source

    Directory of Open Access Journals (Sweden)

    2003-07-01

    Full Text Available The fracture properties of many different types of fibers are covered in a timely new book that will prove to be a tremendous source of information and references for researchers in the wide and diverse field of fibers and composites, says Bill Clegg.

  9. Synergetic effect of green tea on polymer gel dosimeter and determination of optimal wavelength to choose light source for optical computed tomography

    Directory of Open Access Journals (Sweden)

    Sathiya Raj

    2016-03-01

    Full Text Available Purpose: The ultimate aim of this study is to observe the effect of Green tea as a co-antioxidant in PAGAT gel dosimeter and evaluate the appropriate light source for scanning the PAGAT and NIPAM polymer gel.Methods: Both PAGAT (Poly Acrylamide Gelatin Tetrakis hydroxyl phosphonium chloride and NIPAM (N-Isopropyl acrylamide gel were prepared in normoxic condition. The green tea extract (GTE was prepared and tested only on PAGAT. Co-60 teletherapy machine has been used for irradiation purpose, and the gel samples were scanned using UV-Visible spectrophotometer. Water equivalency of the gel has been tested in terms of their electron density, effective atomic number and Ratio of oxygen and hydrogen (O/H. We have used NIST XCOM database to test the water equivalency.Results: In this study we found that the GTE added to the gel do not respond to the given doses. By adding sugar we can enhance the sensitivity of the gel. Further investigations are required to use Green tea as a co antioxidant concentration of THPC (Tetrakis hydroxymethyl phosphonium chloride. The optimal wavelength with different region for scanning the PAGAT is 450 to 480 nm (Blue region, for NIPAM it is 540 nm and 570 nm (Green and yellow region. The PAGAT and NIPAM showed better sensitivity at 510 nm. Both gels have their effective atomic number closer to water (NIPAM-7.2, PAGAT-7.379.Conclusion: As per our results, we concluded that GTE alone is not an effective co-antioxidant for polymer gels. When the GTE is combined with sugar and THPC, it protects the gel from pre-polymerization. This study strongly suggests that the blue light is an optimal source for scanning the PAGAT and green to yellow light for NIPAM gel. Though both gels were considered as water equivalent, the PAGAT is equivalent to water and the temporal stability of this gel is higher than NIPAM.

  10. Source rock

    OpenAIRE

    Abubakr F. Makky; Mohamed I. El Sayed; Ahmed S. Abu El-Ata; Ibrahim M. Abd El-Gaied; Mohamed I. Abdel-Fattah; Zakaria M. Abd-Allah

    2014-01-01

    West Beni Suef Concession is located at the western part of Beni Suef Basin which is a relatively under-explored basin and lies about 150 km south of Cairo. The major goal of this study is to evaluate the source rock by using different techniques as Rock-Eval pyrolysis, Vitrinite reflectance (%Ro), and well log data of some Cretaceous sequences including Abu Roash (E, F and G members), Kharita and Betty formations. The BasinMod 1D program is used in this study to construct the burial history ...

  11. Spectral range calculation inside the Research Irradiating Facility Army Technology Center using code MCNPX and comparison with the spectra of energy Caesium 137 raised in laboratory; Calculo gama espectral no interior do irradiador de pesquisa do Centro Tecnologico do Exercito utilizando o codigo MCNPX e comparacao com espectros de energia do Cesio 137 levantados em laboratorio

    Energy Technology Data Exchange (ETDEWEB)

    Gomes, Renato G.; Rebello, Wilson F.; Cavaliere, Marcos Paulo; Vellozo, Sergio O.; Moreira Junior, Luis, E-mail: renatoguedes@ime.eb.br, E-mail: rebello@ime.eb.br, E-mail: eng.cavaliere@gmail.com, E-mail: vellozo@cbpf.br, E-mail: luisjrmoreira@hotmail.com [Instituto Militar de Engenharia (IME), Rio de Janeiro, RJ (Brazil); Vital, Helio C., E-mail: vital@ctex.eb.br [Centro Tecnologico do Exercito (CTEX), Barra de Guaratiba, RJ (Brazil); Silva, Ademir X., E-mail: ademir@con.ufrj.br [Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro, RJ (Brazil)

    2013-07-01

    Using the MCNPX code, the objective was to calculate by means of computer simulation spectroscopy range inside the irradiation chamber upper radiator gamma research irradiating facility Army Technology Center (CTEx). The calculations were performed in the spectral range usual 2 points for research purposes irradiating the energy spectra of gamma rays from the source of Cesium chloride 137. Sought the discretization of the spectrum in 100 channels at points of upper bound of 1cm higher and lower dose rates previously known. It was also conducted in the laboratory lifting the spectrum of Cesium-137 source using NaI scintillator detector and multichannel analyzer. With the source spectrum Cesium-137 contained in the literature and raised in the laboratory, both used as reference for comparison and analysis in terms of probability of emission maximum of 0.661 MeV The spectra were quite consistent in terms of the behavior of the energy distributions with scores. The position of maximum dose rate showed absorption detection almost maximum energy of 0.661 MeV photopeak In the spectrum of the position of minimum dosage rate, it was found that due to the removal of the source point of interest, some loss detection were caused by Compton scattering. (author)

  12. Open Source

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    一场秋雨一场凉,开源社区的气温却丝毫没有降。刚在北京闭幕的“2006中国开源世界高峰论坛”足以让世界侧目。国际大师云集是最大的亮点,很多熟悉的名字:Andrew Morton(Linux内核开发大师及2.6版本监护人)、Brian Behlendorf(Apache创始人)、David Axmark(MySQL创始人)、Marc Fleury(JBoss创始人)、Larry Augustin(Source Forge创始人)等;其次是中国政府、学术界的支持,包括国家信产部陈英司长和中国工程院倪光南院士、沈昌祥院士等;当然.少不了诸多跨国公司和国内知名企业的参与。

  13. Sources manuscrites

    OpenAIRE

    2014-01-01

    I. SOURCES CONSULTÉES AUX ARCHIVES NATIONALES Série E 1. Minutes d’arrêts du Conseil, arrêts simples en finances 1602 : E 4a, E 4b. 1605 : E 8a, E 8b, E 8c-9a, E 9b, E 9c. 1608 : E 16a, E 16b, E 18a, E 18b, E 19a, E 19b. 1620 : E 63a E 63b, E 64a, E 64b-65a, E 65b. 1689 : E 579a, E 579b, E 580, E 581, E 582, E 583, E 584a, E 584b, E 585a, E 585b, E 586a, E 586b 1750 : E 1260a E 1260b, E 1261a E 1261b, E 1262a, E 1262b, E 1262e, E 1263a, E 1263b, E 1264a, E 1264b, E 1265a, E 1265b, E 1266a, E ...

  14. Wide Area Recovery and Resiliency Program (WARRP) Knowledge Enhancement Events: CBR Workshop After Action Report

    Science.gov (United States)

    2012-01-01

    Intermediate Public messaging should minimize stressful information and images in the media. Medical surveillance should include ocular, asthmatic, cancer ...Radiological Scenario Introduction Cesium 137 Threat: What is it? Acute & Chronic Exposures 0930 – 1030 Breakout Groups for the 6 RSF’s – Short Term...Radioisotope Background Cesium -137 (137Cs) is a radioactive isotope of cesium . The half-life of cesium -137 is 30.17 years. Because of the chemical

  15. Dirty Bombs: The Technical Aspects of Radiological Dispersion Devices

    Science.gov (United States)

    2004-06-01

    www.afrri.usuhs.mil/www/outreach/training.htm last accessed: 20APR04 xxiv Neifert, Alex. Case Study: Accidental Leakage of Cesium-137 in Goiania , Brazil, in...www.berkeleynucleonics.com/radiation/rindex.htm last accessed: 07JUN04 viii Neifert, Alex. Case Study: Accidental Leakage of Cesium-137 in Goiania ...Accidental Leakage of Cesium-137 in Goiania , Brazil, in 1987, http://www.nbc- med.org/SiteContent/MedRef/OnlineRef/CaseStudies/csgoiania.html last

  16. Sources contributing to radioactive contamination of the Techa river and areas surrounding the Mayak production association, Urals, Russia

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-12-31

    A Russian-Norwegian expert group has performed joint investigations of possible impacts of the Mayak plant on the contamination of the Arctic Ocean. This plant that was the first in the former Soviet Union to produce nuclear weapons material, had five special nuclear reactors for production of plutonium and a facility for separation of the plutonium as weapons material. A system of dams along the upper part of Techa River was constructed in order to retain most of the radioactivity, creating several artificial water reservoirs along the old river bed. The paper describes the results of the investigations of the working group. it is concluded that sediment samples from reservoir No. 10 and 11, and from the floodplain along the upper Techa River, have the highest radioactivities (more than 2 MBq/kg d.w. of cesium-137). Flooding of the surrounding swamp and rupture in the reservoirs may cause substantial releases to the river system and thus contaminate the Arctic waters. Also transport of radioactivity by underground water from the reservoirs may contaminate the river system. The future work of the group will be focussed on risk assessment of potential accident scenarios, and possible long-term consequences for man and the environment. 21 refs.

  17. Risks and management of radiation exposure.

    Science.gov (United States)

    Yamamoto, Loren G

    2013-09-01

    High-energy ionizing radiation is harmful. Low-level exposure sources include background, occupational, and medical diagnostics. Radiation disaster incidents include radioactive substance accidents and nuclear power plant accidents. Terrorism and international conflict could trigger intentional radiation disasters that include radiation dispersion devices (RDD) (a radioactive dirty bomb), deliberate exposure to industrial radioactive substances, nuclear power plant sabotage, and nuclear weapon detonation. Nuclear fissioning events such as nuclear power plant incidents and nuclear weapon detonation release radioactive fallout that include radioactive iodine 131, cesium 137, strontium 90, uranium, plutonium, and many other radioactive isotopes. An RDD dirty bomb is likely to spread only one radioactive substance, with the most likely substance being cesium 137. Cobalt 60 and strontium 90 are other RDD dirty bomb possibilities. In a radiation disaster, stable patients should be decontaminated to minimize further radiation exposure. Potassium iodide (KI) is useful for iodine 131 exposure. Prussian blue (ferric hexacyanoferrate) enhances the fecal excretion of cesium via ion exchange. Ca-DTPA (diethylenetriaminepentaacetic acid) and Zn-DTPA form stable ionic complexes with plutonium, americium, and curium, which are excreted in the urine. Amifostine enhances chemical and enzymatic repair of damaged DNA. Acute radiation sickness ranges in severity from mild to lethal, which can be assessed by the nausea/vomiting onset/duration, complete blood cell count findings, and neurologic symptoms.

  18. Analysis, method and techniques for the studying of Cesium-137 transfer from soil to plants (maize and beans) (continuation of the technical report GSR-91-20); Analisis, metodo y tecnicas para estudio de transferencia de Cesio-137 de suelo a plantas (maiz y frijol) (continuacion del informe tecnico GSR-91-20)

    Energy Technology Data Exchange (ETDEWEB)

    Cervantes N, M.L

    1992-12-15

    In this report the complete results of transfer of corn and bean whose objective is to determine the transfer of Cs-137 via: soil {yields} root {yields} plant, which is determined by the transfer factors or concentration factors (FC), which indicates the incorporation from Cs-137 to soil and plant starting from two models of compartments which were already described in the technical report GSR-91-20-1 that precedes to this are presented. These results correspond to that carried out during the agricultural cycle of 1991, as well as the first results corresponding to 1992 in the radioactive wastes storage center (CADER) in Mexico. (Author)

  19. Cesium 137 and cesium 134 in roe deer from the north and central Hessen area: Measurement of the contamination in muscle tissue after the Chernobyl accident. Caesium 137 und Caesium 134 in Rehwild aus Nord- und Mittelhessen: Untersuchungen zur Kontamination von Muskelgewebe nach dem Reaktorunfall in Tschernobyl

    Energy Technology Data Exchange (ETDEWEB)

    Georgii, S.; Brunn, H.; Eskens, U. (Staatliches Medizinal-, Lebensmittel- und Veterinaeruntersuchungsamt Mittelhessen, Giessen (Germany, F.R.))

    1989-06-01

    The present report describes the amount of incorporated 134 and 137 cesium in the muscle tissue of 330 roe deer, which were referred for routine necropsy between 1986 and 1988. The amount of incorporated radiocesium was markedly decreased in 1987 and 1988 compared with 1986. However, a seasonal fluctuation with increase of the measured incorporated radioactivity during the autumn months was observed in 1987 and 1988. (orig.).

  20. Concentration levels of cesium-137 in soils of the municipalities of Guadalupe and Zacatecas before the accident of Fukushima Daiichi; Niveles de concentracion de cesio-137 en suelos de los municipios de Guadalupe y Zacatecas antes del accidente de Fukushima Daiichi

    Energy Technology Data Exchange (ETDEWEB)

    Mireles, F.; Davila, J. I.; Pinedo, J. L.; Lopez, H.; Rios, C.; Saucedo, S. A.; Flores, F. E., E-mail: fmireles@uaz.edu.mx [Universidad Autonoma de Zacatecas, Unidad Academica de Estudios Nucleares, Cipres No. 10, Fracc. La Penuela, 98068 Zacatecas (MX)

    2011-11-15

    The study of the emitter radioisotopes of gamma-rays in soil is very important considering damages to the health and quality of the environment. The main objective of this work is the study of the concentration of the artificial radioisotope {sup 137}Cs in soil of the cities and municipalities of Zacatecas and Guadalupe of the Zacatecas State, Mexico. The study was carried out in two stages for different times, the first stage corresponded to the cities of Zacatecas and Guadalupe in 2000; and the second corresponded to the municipalities of Zacatecas and Guadalupe in 2008. The first study region was the cities of Zacatecas and Guadalupe, and environs where 20 soil samples were obtained. The second study region was inside the municipalities of Guadalupe and Zacatecas and 44 samples of near soil to the communities with major population in both municipalities were obtained. A spectrometry system of gamma-rays was used based on a coaxial detector of germanium hyper pure of high resolution, and was calculated the concentration of the {sup 137}Cs with the energy photo-pick 661.66 KeV. In this work the activity concentrations of the {sup 137}Cs in soil are presented and their variation in function of the time. These data will be a reference to evaluate a possible increment of the {sup 137}Cs because of the accident of Fukushima Daiichi (Japan) nuclear power plant happened March 11, 2011. (Author)

  1. Mesoscale, Sources and Models: Sources for Nitrogen in the Atmosphere

    DEFF Research Database (Denmark)

    Hertel, O.

    1994-01-01

    Projektet Mesoscales, Sources and Models: Sources for Nitrogen in the Atmosphere er opdelt i 3 delprojekter: Sources - farmland, Sources - sea og Sources - biogenic nitrogen.......Projektet Mesoscales, Sources and Models: Sources for Nitrogen in the Atmosphere er opdelt i 3 delprojekter: Sources - farmland, Sources - sea og Sources - biogenic nitrogen....

  2. Sources management; La gestion des sources

    Energy Technology Data Exchange (ETDEWEB)

    Mansoux, H.; Gourmelon; Scanff, P.; Fournet, F. [Institut de Radioprotection et de Surete Nucleaire, 92 - Fontenay-aux-Roses (France); Murith, Ch. [Office Federal de la SantePublique (Switzerland); Saint-Paul, N. [NOVAR, 75 - Paris (France); Colson, P. [Electricite de France (EDF/DPN), 93 - Saint-Denis (France); Jouve, A.; Feron, F. [Direction Generale de al Surete Nucleaire et de la Radioprotection, 75 - Paris (France); Haranger, D. [Electricite de France (EDF), 75 - Paris (France); Mathieu, P. [Institut Pasteur, 75 - Paris (France); Paycha, F. [CHU Louis Mourier, Unitede Medecine Nucleaire Assistance Publique-Hopitaux de Paris, 92 - Colombes (France); Israel, S. [CEGELEC NDT et la gestion des sources radioactives (France); Auboiroux, B. [APAVE (France); Chartier, P. [DRIRE de Basse-Normandie, Div. Surete Nucleaire et Radioprotection, 14 - Caen (France)

    2005-07-01

    Organized by the section of technical protection of the French society of radiation protection ( S.F.R.P.), these two days had for objective to review the evolution of the rule relative to the sources of ionising radiations 'sealed and unsealed radioactive sources, electric generators'. They addressed all the actors concerned by the implementation of the new regulatory system in the different sectors of activities ( research, medicine and industry): Authorities, manufacturers, and suppliers of sources, holders and users, bodies involved in the approval of sources, carriers. (N.C.)

  3. Modeling Frequency Comb Sources

    Directory of Open Access Journals (Sweden)

    Li Feng

    2016-06-01

    Full Text Available Frequency comb sources have revolutionized metrology and spectroscopy and found applications in many fields. Stable, low-cost, high-quality frequency comb sources are important to these applications. Modeling of the frequency comb sources will help the understanding of the operation mechanism and optimization of the design of such sources. In this paper,we review the theoretical models used and recent progress of the modeling of frequency comb sources.

  4. Ion Source DECRIS-3

    CERN Document Server

    Efremov, A; Lebedev, A N; Loginov, V N; Yazvitsky, N Yu

    1999-01-01

    The ECR ion source DECRIS-3 is the copy of the mVINIS ion source which was designed and built in Dubna for the TESLA Accelerator Installation (Belgrade, Yugoslavia) in 1997. The assembly of the source was completely finished in the end of 1998 and then it was installed at the FLNR ECR test bench. The source was successfully tested with some gases and metals by using the MIVOC technique. In nearest future the source will be capable of ECR plasma heating using two different frequencies simultaneously. We are also going to use the DECRIS-3 ion source to design 1+ -> n+ technique for the DRIBs (Dubna Radioactive Ion Beams) project.

  5. Sodium and Food Sources

    Science.gov (United States)

    ... Sources Top 10 Sources of Sodium How to Reduce Sodium Sodium Reduction Resources for Everyone Sodium Reduction Fact ... in processed food [PDF-867K] and how to reduce sodium. Sodium Reduction Is Challenging Types of food matter: ...

  6. Spallation Neutron Source (SNS)

    Data.gov (United States)

    Federal Laboratory Consortium — The SNS at Oak Ridge National Laboratory is a next-generation spallation neutron source for neutron scattering that is currently the most powerful neutron source in...

  7. 2011 NATA - Emissions Sources

    Data.gov (United States)

    U.S. Environmental Protection Agency — This dataset includes all emissions sources that were modeled in the 2011 National Air Toxics Assessment (NATA), inlcluding point, nonpoint, and mobile sources, and...

  8. Electron Beam Ion Sources

    OpenAIRE

    Zschornacka, G.; Schmidt, M.; Thorn, A.

    2014-01-01

    Electron beam ion sources (EBISs) are ion sources that work based on the principle of electron impact ionization, allowing the production of very highly charged ions. The ions produced can be extracted as a DC ion beam as well as ion pulses of different time structures. In comparison to most of the other known ion sources, EBISs feature ion beams with very good beam emittances and a low energy spread. Furthermore, EBISs are excellent sources of photons (X-rays, ultraviolet, extreme ultraviole...

  9. Open Source Business Solutions

    Directory of Open Access Journals (Sweden)

    Ion IVAN

    2008-01-01

    Full Text Available This analyses the Open source movement. Open source development process and management is seen different from the classical point of view. This focuses on characteristics and software market tendencies for the main Open source initiatives. It also points out the labor market future evolution for the software developers.

  10. Investigating Primary Source Literacy

    Science.gov (United States)

    Archer, Joanne; Hanlon, Ann M.; Levine, Jennie A.

    2009-01-01

    Primary source research requires students to acquire specialized research skills. This paper presents results from a user study testing the effectiveness of a Web guide designed to convey the concepts behind "primary source literacy". The study also evaluated students' strengths and weaknesses when conducting primary source research. (Contains 3…

  11. Evaluation of the Biological Shields of the Secondary Standard Dosimetry Laboratory of Ghana Using MCNP5

    Directory of Open Access Journals (Sweden)

    P. Deatanyah

    2012-03-01

    Full Text Available The primary objective with radiation sources and facilities is the protection of both radiation workers and the general public. The biological shields of the Secondary Standard Dosimetry Laboratory of the Radiation Protection Institute (RPI Ghana had been evaluated for a collimated isotropic cesium-137 source for calibration purpose using MCNP5 code. The dose rate at supervised areas ranged from 0.57 to 8.35 :Sv/h and 0.26 to 10.22 :Sv/h at control areas when the source was panoramic. When the source was collimated, the dose rate ranged from 0.05 to 0.30 :Sv/h at supervised areas and 0.23 to 8.88 :Sv/h at control areas for 22.2 GBq of the cesium-137 source. The scatter contribution from the surfaces of the walls and roofs were also accounted for. The scatter radiation in the room decreased to 400 :Sv/h when the source was first collimated and to 3.5 :Sv/h when the source was further collimated. These results agreed quite well with experimental measurement. To effectively protect the staff, a narrow beam of 1.2 cm diameter which was defined at 1.0 m by the total surface of the ISO slab phantom was recommended to reduce the dose rate to less than 1.5 :Sv/h outside the calibration bunker even when the current activity is doubled. It was concluded that the 4.7 cm diameter of the existing narrow beam should be decreased to 1.2 cm by further collimation of the beam.

  12. Global Sourcing of Services

    DEFF Research Database (Denmark)

    Ørberg Jensen, Peter D.; Petersen, Bent

    2013-01-01

    The global sourcing of services offers high returns but is also associated with high risks. The extent to which firms engage in ‘transformational’ global sourcing (i.e., global sourcing implying considerable changes in the home organization) chiefly depends on management's comfort zone which......, in turn, is determined by managers' risk perceptions, risk tolerance, and ability to employ risk-reducing measures. Many firms move into transformational global sourcing more or less deliberately. However, as the human asset specificity of the global sourcing operation increases, managers find themselves...

  13. DC source assemblies

    Science.gov (United States)

    Campbell, Jeremy B; Newson, Steve

    2013-02-26

    Embodiments of DC source assemblies of power inverter systems of the type suitable for deployment in a vehicle having an electrically grounded chassis are provided. An embodiment of a DC source assembly comprises a housing, a DC source disposed within the housing, a first terminal, and a second terminal. The DC source also comprises a first capacitor having a first electrode electrically coupled to the housing, and a second electrode electrically coupled to the first terminal. The DC source assembly further comprises a second capacitor having a first electrode electrically coupled to the housing, and a second electrode electrically coupled to the second terminal.

  14. Noise Source Location Optimization

    Directory of Open Access Journals (Sweden)

    Ed O’Keefe

    1994-01-01

    Full Text Available This article describes a method to determine locations of noise sources that minimize modal coupling in complex acoustic volumes. Using the acoustic source scattering capabilities of the boundary element method, predictions are made of mode shape and pressure levels due to various source locations. Combining knowledge of the pressure field with a multivariable function minimization technique, the source location generating minimum pressure levels can be determined. The analysis also allows for an objective comparison of “best/worst” locations. The technique was implemented on a personal computer for the U.S. Space Station, predicting 5–10 dB noise reduction using optimum source locations.

  15. Markov information sources

    Science.gov (United States)

    Massey, J. L.

    1975-01-01

    A regular Markov source is defined as the output of a deterministic, but noisy, channel driven by the state sequence of a regular finite-state Markov chain. The rate of such a source is the per letter uncertainty of its digits. The well-known result that the rate of a unifilar regular Markov source is easily calculable is demonstrated, where unifilarity means that the present state of the Markov chain and the next output of the deterministic channel uniquely determine the next state. At present, there is no known method to calculate the rate of a nonunifilar source. Two tentative approaches to this unsolved problem are given, namely source identical twins and the master-slave source, which appear to shed some light on the question of rate calculation for a nonunifilar source.

  16. Wavelength sweepable laser source

    DEFF Research Database (Denmark)

    2014-01-01

    Wavelength sweepable laser source is disclosed, wherein the laser source is a semiconductor laser source adapted for generating laser light at a lasing wavelength. The laser source comprises a substrate, a first reflector, and a second reflector. The first and second reflector together defines...... and having a rest position, the second reflector and suspension together defining a microelectromechanical MEMS oscillator. The MEMS oscillator has a resonance frequency and is adapted for oscillating the second reflector on either side of the rest position.; The laser source further comprises electrical...... connections adapted for applying an electric field to the MEMS oscillator. Furthermore, a laser source system and a method of use of the laser source are disclosed....

  17. Neuromagnetic source reconstruction

    Energy Technology Data Exchange (ETDEWEB)

    Lewis, P.S.; Mosher, J.C. [Los Alamos National Lab., NM (United States); Leahy, R.M. [University of Southern California, Los Angeles, CA (United States)

    1994-12-31

    In neuromagnetic source reconstruction, a functional map of neural activity is constructed from noninvasive magnetoencephalographic (MEG) measurements. The overall reconstruction problem is under-determined, so some form of source modeling must be applied. We review the two main classes of reconstruction techniques-parametric current dipole models and nonparametric distributed source reconstructions. Current dipole reconstructions use a physically plausible source model, but are limited to cases in which the neural currents are expected to be highly sparse and localized. Distributed source reconstructions can be applied to a wider variety of cases, but must incorporate an implicit source, model in order to arrive at a single reconstruction. We examine distributed source reconstruction in a Bayesian framework to highlight the implicit nonphysical Gaussian assumptions of minimum norm based reconstruction algorithms. We conclude with a brief discussion of alternative non-Gaussian approachs.

  18. Global Sourcing Flexibility

    DEFF Research Database (Denmark)

    Ørberg Jensen, Peter D.; Petersen, Bent

    2013-01-01

    sourcing flexibility. Here we draw on prior research in the fields of organizational flexibility, international business and global sourcing as well as case examples and secondary studies. In the second part of the paper, we discuss the implications of global sourcing flexibility for firm strategy......Recent studies show that flexibility is a key concern for firms that engage in the global sourcing of services. In this conceptual paper, we seek to explore two central aspects of global sourcing flexibility: In the first part of the paper, we provide a definition of the construct of global...... and operations against the backdrop of the theory-based definition of the construct. We discuss in particular the importance of global sourcing flexibility for operational performance stability, and the trade-off between specialization benefits, emerging from location and service provider specialization, versus...

  19. Acoustic emission source modeling

    Directory of Open Access Journals (Sweden)

    Hora P.

    2010-07-01

    Full Text Available The paper deals with the acoustic emission (AE source modeling by means of FEM system COMSOL Multiphysics. The following types of sources are used: the spatially concentrated force and the double forces (dipole. The pulse excitation is studied in both cases. As a material is used steel. The computed displacements are compared with the exact analytical solution of point sources under consideration.

  20. Source and replica calculations

    Energy Technology Data Exchange (ETDEWEB)

    Whalen, P.P.

    1994-02-01

    The starting point of the Hiroshima-Nagasaki Dose Reevaluation Program is the energy and directional distributions of the prompt neutron and gamma-ray radiation emitted from the exploding bombs. A brief introduction to the neutron source calculations is presented. The development of our current understanding of the source problem is outlined. It is recommended that adjoint calculations be used to modify source spectra to resolve the neutron discrepancy problem.

  1. Source tree composition

    OpenAIRE

    Jonge, de, H.J.

    2002-01-01

    Dividing software systems in components improves software reusability as well as software maintainability. Components live at several levels, we concentrate on the implementation level where components are formed by source files, divided over directory structures. Such source code components are usually strongly coupled in the directory structure of a software system. Their compilation is usually controlled by a single global build process. This entangling of source trees and build processes ...

  2. Pulsed spallation Neutron Sources

    Energy Technology Data Exchange (ETDEWEB)

    Carpenter, J.M. [Argonne National Lab., IL (United States)

    1994-12-31

    This paper reviews the early history of pulsed spallation neutron source development at Argonne and provides an overview of existing sources world wide. A number of proposals for machines more powerful than currently exist are under development, which are briefly described. The author reviews the status of the Intense Pulsed Neutron Source, its instrumentation, and its user program, and provides a few examples of applications in fundamental condensed matter physics, materials science and technology.

  3. Brachytherapy for stage IIIB squamous cell carcinoma of the uterine cervix: survival and toxicity

    Energy Technology Data Exchange (ETDEWEB)

    Zuliani, Antonio Carlos; Cunha, Maercio de Oliveira, E-mail: aczo.rt@gmail.co [Universidade Estadual de Campinas (UNICAMP), SP (Brazil); Esteves, Sergio C.B. [Universidade Estadual de Campinas (UNICAMP), SP (Brazil). Faculdade de Ciencias Medicas. Secao de Radioterapia; Teixeira, Julio Cesar [Universidade Estadual de Campinas (UNICAMP), SP (Brazil). Faculdade de Ciencias Medicas. Dept. de Tocoginecologia

    2010-07-01

    Objective: to compare survival and toxicity of three different treatments for stage IIIB cervix cancer: low-dose-rate (LDR), high-dose-rate (HDR) brachytherapy and association of HDR and chemotherapy. Methods: between 1985 and 2005, 230 patients with FIGO stage IIIB squamous cell carcinoma of the uterine cervix received 4-field pelvic teletherapy at doses between 40 and 50.4 Gy, with a different complementation in each group. The LDRB group, with 42 patients, received one or two insertions of LDR, with Cesium-137, in a total dose of 80 to 100Gy at point A. The HDR group, 155 patients received HDR in 4 weekly 7 Gy fractions and 9 Gy to 14.4 Gy applied to the involved parametria. The CHT group, 33 patients, were given the same treatment as the HDR group and received 5 or 6 weekly cycles of cisplatin, 40 mg per m2. Results: the five-year progression-free survival (PFS) was 60% for the HDR group and 45% for the LDR group, and the two-year PFS for the CHT group was 65% (p = 0.02). The five-year Overall Survival (OS) was 65% for the HDR group and 49% for the LDR group. The two-year OS was 86% for the CHT group (p 0.02). Rectum toxicity grade II was 7% for the LDR group, 4% for the HDR group and 7% for the CHT group that had one case of rectum toxicity grade IV. Conclusion: patients that received HDR had better OS and PFS. The Chemotherapy-HDR association showed no benefit when compared to HDR only. Toxicity rates showed no difference between the three groups. (author)

  4. Advanced Photon Source (APS)

    Data.gov (United States)

    Federal Laboratory Consortium — The Advanced Photon Source (APS) at the U.S. Department of Energy's Argonne National Laboratoryprovides this nation's (in fact, this hemisphere's) brightest storage...

  5. Source SDK development essentials

    CERN Document Server

    Bernier, Brett

    2014-01-01

    The Source Authoring Tools are the pieces of software used to create custom content for games made with Valve's Source engine. Creating mods and maps for your games without any programming knowledge can be time consuming. These tools allow you to create your own maps and levels without the need for any coding knowledge. All the tools that you need to start creating your own levels are built-in and ready to go! This book will teach you how to use the Authoring Tools provided with Source games and will guide you in creating your first maps and mods (modifications) using Source. You will learn ho

  6. PORTABLE SOURCE OF RADIOACTIVITY

    Science.gov (United States)

    Goertz, R.C.; Ferguson, K.R.; Rylander, E.W.; Safranski, L.M.

    1959-06-16

    A portable source for radiogiaphy or radiotherapy is described. It consists of a Tl/sup 170/ or Co/sup 60/ source mounted in a rotatable tungsten alloy plug. The plug rotates within a brass body to positions of safety or exposure. Provision is made for reloading and carrying the device safely. (T.R.H.)

  7. The Chandra Source Catalog

    CERN Document Server

    Evans, Ian N; Glotfelty, Kenny J; Anderson, Craig S; Bonaventura, Nina R; Chen, Judy C; Davis, John E; Doe, Stephen M; Evans, Janet D; Fabbiano, Giuseppina; Galle, Elizabeth C; Gibbs, Danny G; Grier, John D; Hain, Roger M; Hall, Diane M; Harbo, Peter N; Xiangqun,; He,; Houck, John C; Karovska, Margarita; Kashyap, Vinay L; Lauer, Jennifer; McCollough, Michael L; McDowell, Jonathan C; Miller, Joseph B; Mitschang, Arik W; Morgan, Douglas L; Mossman, Amy E; Nichols, Joy S; Nowak, Michael A; Plummer, David A; Refsdal, Brian L; Rots, Arnold H; Siemiginowska, Aneta; Sundheim, Beth A; Tibbetts, Michael S; Van Stone, David W; Winkelman, Sherry L; Zografou, Panagoula

    2010-01-01

    The Chandra Source Catalog (CSC) is a general purpose virtual X-ray astrophysics facility that provides access to a carefully selected set of generally useful quantities for individual X-ray sources, and is designed to satisfy the needs of a broad-based group of scientists, including those who may be less familiar with astronomical data analysis in the X-ray regime. The first release of the CSC includes information about 94,676 distinct X-ray sources detected in a subset of public ACIS imaging observations from roughly the first eight years of the Chandra mission. This release of the catalog includes point and compact sources with observed spatial extents <~ 30''. The catalog (1) provides access to the best estimates of the X-ray source properties for detected sources, with good scientific fidelity, and directly supports scientific analysis using the individual source data; (2) facilitates analysis of a wide range of statistical properties for classes of X-ray sources; and (3) provides efficient access to ...

  8. Radiation Source Replacement Workshop

    Energy Technology Data Exchange (ETDEWEB)

    Griffin, Jeffrey W.; Moran, Traci L.; Bond, Leonard J.

    2010-12-01

    This report summarizes a Radiation Source Replacement Workshop in Houston Texas on October 27-28, 2010, which provided a forum for industry and researchers to exchange information and to discuss the issues relating to replacement of AmBe, and potentially other isotope sources used in well logging.

  9. Sound and Sound Sources

    DEFF Research Database (Denmark)

    Larsen, Ole Næsbye; Wahlberg, Magnus

    2017-01-01

    . To produce directional sounds, even higher frequencies and shorter wavelengths are needed. In this context ‘short’ is measured relative to the size of the sound source. Some sound sources, such as dipoles and pistons, are inherently directional, whereas others, such as monopoles, are inherently...

  10. Variability in GPS sources

    NARCIS (Netherlands)

    Jauncey, DL; King, EA; Bignall, HE; Lovell, JEJ; Kedziora-Chudczer, L; Tzioumis, AK; Tingay, SJ; Macquart, JP; McCulloch, PM

    2003-01-01

    Flux density monitoring data at 2.3 and 8.4 GHz is presented for a sample of 33 southern hemisphere GPS sources, drawn from the 2.7 GHz Parkes survey. This monitoring data, together with VLBI monitoring data, shows that a small fraction of these sources, similar to10%, vary. Their variability falls

  11. Source tree composition

    NARCIS (Netherlands)

    Jonge, M. de

    2002-01-01

    Dividing software systems in components improves software reusability as well as software maintainability. Components live at several levels, we concentrate on the implementation level where components are formed by source files, divided over directory structures. Such source code components are usu

  12. Using Primary Source Documents.

    Science.gov (United States)

    Mintz, Steven

    2003-01-01

    Explores the use of primary sources when teaching about U.S. slavery. Includes primary sources from the Gilder Lehrman Documents Collection (New York Historical Society) to teach about the role of slaves in the Revolutionary War, such as a proclamation from Lord Dunmore offering freedom to slaves who joined his army. (CMK)

  13. Fifth generation light sources

    Science.gov (United States)

    Romaniuk, Ryszard S.

    2016-12-01

    Coherent light sources are one of the most fundamental research tools in biology, technology and in other areas. Synchrotron light source consists of a few basic parts: energy source - which is an electron beam accelerator, energy converter between electron and photon beams - which is an undulator, and photon user experimental lines. Each of these parts is separately a complex system, which is currently a subject to fast technological development. Future light sources of the fifth generation are based on completely new solutions of these fundamental parts, in comparison with the sources of the previous generations. Energy source is a new generation laser - plasma accelerator with electrical field in the area of multiple GV/m. A miniature undulator is tested in the MEMS technology from new materials. Classical light beam lines, vacuum, and difficult for management and beam distribution, change their meaning in the case of availability of miniature undulators positioned immediately at or even inside the experimental stations. After an introduction concerning the light sources of the previous generations, the article shows current research efforts on the mentioned key components of the fifth generation light sources. In some cases this is a continuation and modernization of the previous technologies, in the majority it is a brave endeavour to apply completely new technologies, like laser - plasma acceleration.

  14. Creating Open Source Conversation

    Science.gov (United States)

    Sheehan, Kate

    2009-01-01

    Darien Library, where the author serves as head of knowledge and learning services, launched a new website on September 1, 2008. The website is built with Drupal, an open source content management system (CMS). In this article, the author describes how she and her colleagues overhauled the library's website to provide an open source content…

  15. Radioactive Sources Service

    CERN Multimedia

    2007-01-01

    Please note that the radioactive sources service will be open by appointment only every Monday, Wednesday and Friday during CERN working hours (instead of alternate weeks). In addition, please note that our 2007 schedule is available on our web site: http://cern.ch/service-rp-sources

  16. Radioactive Sources Service

    CERN Multimedia

    2007-01-01

    Please note that the radioactive sources service will be open by appointment only every Monday, Wednesday and Friday during CERN working hours (instead of alternate weeks). In addition, please note that our 2007 schedule is available on our web site. http://cern.ch/service-rp-sources

  17. Neutron sources and applications

    Energy Technology Data Exchange (ETDEWEB)

    Price, D.L. [ed.] [Argonne National Lab., IL (United States); Rush, J.J. [ed.] [National Inst. of Standards and Technology, Gaithersburg, MD (United States)

    1994-01-01

    Review of Neutron Sources and Applications was held at Oak Brook, Illinois, during September 8--10, 1992. This review involved some 70 national and international experts in different areas of neutron research, sources, and applications. Separate working groups were asked to (1) review the current status of advanced research reactors and spallation sources; and (2) provide an update on scientific, technological, and medical applications, including neutron scattering research in a number of disciplines, isotope production, materials irradiation, and other important uses of neutron sources such as materials analysis and fundamental neutron physics. This report summarizes the findings and conclusions of the different working groups involved in the review, and contains some of the best current expertise on neutron sources and applications.

  18. Nonlinear Source Emulator

    DEFF Research Database (Denmark)

    Nguyen-Duy, Khiem

    and remains the prime source of energy in non-terrestrial applications such as those in sky-explorers. However, a renewable energy source is expensive, bulky, and its performance is weather dependent, which make testing of downstream converters very difficult. As a result, a nonlinear source emulator (NSE......) is a good solution to solve the problems associated with the use of real nonlinear sources in testing phases. However, a recent technical survey conducted during this work shows that most existing NSEs have only been concerned with simulating nonlinear systems in terrestrial applications. Furthermore......, their dynamic performance were not fast enough in order to imitate how a real nonlinear energy source would react under extreme conditions and operation modes. Particularly, a system in the sky can experience a step change of sunlight irradiation. Moreover, operation modes may include load step between nominal...

  19. Peristaltic ion source

    Energy Technology Data Exchange (ETDEWEB)

    Brown, I.G.; Anders, A.; Anders, S.; Dickinson, M.R.; MacGill, R.A.

    1995-08-01

    Conventional ion sources generate energetic ion beams by accelerating the plasma-produced ions through a voltage drop at the extractor, and since it is usual that the ion beam is to propagate in a space which is at ground potential, the plasma source is biased at extractor voltage. For high ion beam energy the plasma source and electrical systems need to be raised to high voltage, a task that adds considerable complexity and expense to the total ion source system. The authors have developed a system which though forming energetic ion beams at ground potential as usual, operates with the plasma source and electronics at ground potential also. Plasma produced by a nearby source streams into a grided chamber that is repetitively pulsed from ground to high positive potential, sequentially accepting plasma into its interior region and ejecting it energetically. They call the device a peristaltic ion source. In preliminary tests they`ve produced nitrogen and titanium ion beams at energies from 1 to 40 keV. Here they describe the philosophy behind the approach, the test embodiment that they have made, and some preliminary results.

  20. Advanced positron sources

    Energy Technology Data Exchange (ETDEWEB)

    Variola, A., E-mail: variola@lal.in2p3.fr

    2014-03-11

    Positron sources are a critical system for the future lepton colliders projects. Due to the large beam emittance at the production and the limitation given by the target heating and mechanical stress, the main collider parameters fixing the luminosity are constrained by the e{sup +} sources. In this context also the damping ring design boundary conditions and the final performance are given by the injected positron beam. At present different schemes are being taken into account in order to increase the production and the capture yield of the positron sources, to reduce the impact of the deposited energy in the converter target and to increase the injection efficiency in the damping ring. The final results have a strong impact not only on the collider performance but also on its cost optimization. After a short introduction illustrating their fundamental role, the basic positron source scheme and the performance of the existing sources will be illustrated. The main innovative designs for the future colliders advanced sources will be reviewed and the different developed technologies presented. Finally the positrons-plasma R and D experiments and the futuristic proposals for positron sources will reviewed.

  1. Microwave Discharge Ion Sources

    CERN Document Server

    Celona, L

    2013-01-01

    This chapter describes the basic principles, design features and characteristics of microwave discharge ion sources. A suitable source for the production of intense beams for high-power accelerators must satisfy the requirements of high brightness, stability and reliability. The 2.45 GHz off-resonance microwave discharge sources are ideal devices to generate the required beams, as they produce multimilliampere beams of protons, deuterons and singly charged ions. A description of different technical designs will be given, analysing their performance, with particular attention being paid to the quality of the beam, especially in terms of its emittance.

  2. Characterization of gaseous detectors at the CERN Gamma Irradiation Facility: GEM performance in presence of high background radiation

    CERN Document Server

    AUTHOR|(CDS)2097588

    Muon detection is an efficient tool to recognize interesting physics events over the high background rate expected at the Large Hadron Collider (LHC) at CERN. The muon systems of the LHC experiments are based on gaseous ionization detectors. In view of the High-Luminosity LHC (HL-LHC) upgrade program, the increasing of background radiation could affect the gaseous detector performance, especially decreasing the efficiency and shortening the lifetime through ageing processes. The effects of charge multiplication, materials and gas composition on the ageing of gaseous detectors have been studied for decades, but the future upgrade of LHC requires additional studies on this topic. At the CERN Gamma Irradiation Facility (GIF++), a radioactive source of cesium-137 with an activity of 14 TBq is used to reproduce reasonably well the expected background radiation at HL-LHC. A muon beam has been made available to study detector performance. The characterization of the beam trigger will be discussed in the present w...

  3. Inspection of contaminated hot cell ductwork

    Energy Technology Data Exchange (ETDEWEB)

    Muller, R.C.; Herndon, J.N.; Dagenhart, W.K.

    1989-08-01

    Radiation Sterilization, Incorporated (RSI), of Dekalb County, Georgia, has used Cesium-137 radiation sources for sterilization of medical instruments and other commercial items. The cesium is contained in welded stainless steel capsules. One of these capsules has leaked, allowing the cesium to escape and to contaminate the internals of the sterilization cells including the cell ventilation ductwork penetrating the thick concrete cell roof. This ductwork requires decontamination prior to release of the facility to resume sterilization activities. Due to the small size (20-in. {times} 24-in. cross section) and the long runs embedded in the cell roof, it was determined that remote visual inspection and preliminary radiation mapping of this ductwork was necessary. This report covers the inspection effort and evaluation of the results. 23 figs., 3 tabs.

  4. Electron Beam Ion Sources

    CERN Document Server

    Zschornacka, G; Thorn, A

    2013-01-01

    Electron beam ion sources (EBISs) are ion sources that work based on the principle of electron impact ionization, allowing the production of very highly charged ions. The ions produced can be extracted as a DC ion beam as well as ion pulses of different time structures. In comparison to most of the other known ion sources, EBISs feature ion beams with very good beam emittances and a low energy spread. Furthermore, EBISs are excellent sources of photons (X-rays, ultraviolet, extreme ultraviolet, visible light) from highly charged ions. This chapter gives an overview of EBIS physics, the principle of operation, and the known technical solutions. Using examples, the performance of EBISs as well as their applications in various fields of basic research, technology and medicine are discussed.

  5. Alternative fuel information sources

    Energy Technology Data Exchange (ETDEWEB)

    1994-06-01

    This short document contains a list of more than 200 US sources of information (Name, address, phone number, and sometimes contact) related to the use of alternative fuels in automobiles and trucks. Electric-powered cars are also included.

  6. Public Water Sources

    Data.gov (United States)

    Vermont Center for Geographic Information — This GIS layer consists of the geographic location of active and inactive public (Community, non-transient non-community and transient non-community) water sources...

  7. Environmental Data Sources

    Data.gov (United States)

    Kansas Data Access and Support Center — This database includes gauging stations, climatic data centers, and storet sites. The accuracy of the locations is dependent on the source data for each of the...

  8. Casimir light: the source.

    OpenAIRE

    1993-01-01

    The release of Casimir energy in filling a dielectric hole is identified as the source of coherent sonoluminescence. Qualitative agreement with recently acquired data is found for the magnitude and shape of the spectrum.

  9. EPA Sole Source Aquifers

    Data.gov (United States)

    U.S. Environmental Protection Agency — Information on sole source aquifers (SSAs) is widely used in assessments under the National Environmental Policy Act and at the state and local level. A national...

  10. Thermoelectricity Light Sources

    Institute of Scientific and Technical Information of China (English)

    SHIYongji

    1997-01-01

    A thermoelectricity light source in a gaseous plasma discharge between two electrodes is described,one of which emits electrons thermoionically.The analytical model describing basic physical phenomena is developed.The results are excellent agreement with simulated test.

  11. Advanced Light Source (ALS)

    Data.gov (United States)

    Federal Laboratory Consortium — The Advanced Light Source (ALS), a world leader in soft x-ray science, generates light in the wavelengths needed for examining the atomic and electronic structure of...

  12. Magnetron sputtering source

    Science.gov (United States)

    Makowiecki, Daniel M.; McKernan, Mark A.; Grabner, R. Fred; Ramsey, Philip B.

    1994-01-01

    A magnetron sputtering source for sputtering coating substrates includes a high thermal conductivity electrically insulating ceramic and magnetically attached sputter target which can eliminate vacuum sealing and direct fluid cooling of the cathode assembly. The magnetron sputtering source design results in greater compactness, improved operating characteristics, greater versatility, and low fabrication cost. The design easily retrofits most sputtering apparatuses and provides for safe, easy, and cost effective target replacement, installation, and removal.

  13. Open source molecular modeling.

    Science.gov (United States)

    Pirhadi, Somayeh; Sunseri, Jocelyn; Koes, David Ryan

    2016-09-01

    The success of molecular modeling and computational chemistry efforts are, by definition, dependent on quality software applications. Open source software development provides many advantages to users of modeling applications, not the least of which is that the software is free and completely extendable. In this review we categorize, enumerate, and describe available open source software packages for molecular modeling and computational chemistry. An updated online version of this catalog can be found at https://opensourcemolecularmodeling.github.io.

  14. Radio frequency ion source

    CERN Document Server

    Shen Guan Ren; Gao Fu; LiuNaiYi

    2001-01-01

    The study on Radio Frequency Ion Source is mainly introduced, which is used for CIAE 600kV ns Pulse Neutron Generator; and obtained result is also presented. The RF ion source consists of a diameter phi 25 mm, length 200 mm, coefficient of expansion =3.5 mA, beam current on target >=1.5 mA, beam spot =100 h.

  15. Diversification of energy sources

    Science.gov (United States)

    1975-01-01

    The concept of energy source diversification was introduced as a substitution conservation action. The current status and philosophy behind a diversification program is presented in the context of a national energy policy. Advantages, disadvantages (constraints), and methods of implementation for diversification are discussed. The energy source systems for diversification are listed and an example impact assessment is outlined which deals with the water requirements of the specific energy systems.

  16. Nonpoint Source Pollution.

    Science.gov (United States)

    Mccoy, Nicholas; Chao, Bing; Gang, Daniel Dianchen

    2015-10-01

    The article presents a comprehensive review of research advancing in 2014 on nonpoint source pollution (NPS). The topics presented relate to nonpoint source pollution (NPS) within agricultural and urban areas. NPS pollution from agricultural areas is the main focus in this review. Management of NPS in agricultural, urban and rural areas is presented. Modeling of NPS pollution in different watersheds with various modeling tools is reviewed.

  17. Field emission electron source

    Science.gov (United States)

    Zettl, Alexander Karlwalter; Cohen, Marvin Lou

    2000-01-01

    A novel field emitter material, field emission electron source, and commercially feasible fabrication method is described. The inventive field emission electron source produces reliable electron currents of up to 400 mA/cm.sup.2 at 200 volts. The emitter is robust and the current it produces is not sensitive to variability of vacuum or the distance between the emitter tip and the cathode. The novel emitter has a sharp turn-on near 100 volts.

  18. Cardiomagnetic source imaging

    OpenAIRE

    Pesola, Katja

    2000-01-01

    Magnetocardiographic (MCG) source imaging has received increasing interest in recent years. With a high enough localization accuracy of the current sources in the heart, valuable information can be provided, e.g., for the pre-ablative evaluation of arrhythmia patients. Furthermore, preliminary studies indicate that ischemic areas, i.e. areas which are suffering from lack of oxygen, and infarcted regions could be localized from multichannel MCG recordings. In this thesis, the accuracy of cardi...

  19. Radio source evolution

    CERN Document Server

    Perucho, Manel

    2015-01-01

    Baldwin (1982) wrote that "the distribution of sources in the radio luminosity, P, overall physical size, D, diagram" could be considered as "the radio astronomer's H-R diagram". However, unlike the case of stars, not only the intrinsic properties of the jets, but also those of the host galaxy and the intergalactic medium are relevant to explain the evolutionary tracks of radio radio sources. In this contribution I review the current status of our understanding of the evolution of radio sources from a theoretical and numerical perspective, using the P-D diagram as a framework. An excess of compact (linear size < 10 kpc) sources could be explained by low-power jets being decelerated within the host galaxy, as shown by recent numerical simulations. These decelerated jets could also explain the population of the radio sources that have been recently classified as FR0. I will discuss the possible tracks that radio sources may follow within this diagram, and some of the physical processes that can explain the d...

  20. Characteristics and locations of sources

    Energy Technology Data Exchange (ETDEWEB)

    Lahtinen, J.; Poellaenen, R.; Toivonen, H. [Finnish Centre for Radiation and Nuclear Safety, Helsinki (Finland)

    1997-12-31

    Ten artificial radiation sources were placed in the terrain in order to test the capability of airborne measuring teams to detect them. One of the sources was a line source, others were point sources (three of them collimated). The radionuclides used in the sources were {sup 60}Co, {sup 137}Cs, {sup 99m}Tc and {sup 192}Ir. The source activities ranged from about 26 MBq (one of the cobalt sources) to 0.56 TBq (iridium). (au).

  1. Open Source Telecommunication Companies

    Directory of Open Access Journals (Sweden)

    Peter Liu

    2007-08-01

    Full Text Available Little is known about companies whose core business is selling telecommunications products that lever open source projects. Open source telecommunications (OST companies operate in markets that are very different from typical software product markets. The telecommunications market is regulated, vertically integrated, and proprietary designs and special chips are widely used. For a telecommunications product to be useful, it must interact with both access network products and core network products. Due to specifications in Service Agreements Levels, penalties for failures of telecommunications products are very high. This article shares information that is not widely known, including a list of OST companies and the open source projects on which they depend, the size and diversity of venture capital investment in OST companies, the nature of the commercial product-open source software and company-project relationships, ways in which OST companies make money, benefits and risks of OST companies, and competition between OST companies. Analysis of this information provides insights into the ways in which companies can build business models around open source software. These findings will be of interest to entrepreneurs, top management teams of incumbent companies that sell telecommunications products, and those who care about Ontario's ability to compete globally.

  2. Astrophysics Source Code Library

    CERN Document Server

    Allen, Alice; Berriman, Bruce; Hanisch, Robert J; Mink, Jessica; Teuben, Peter J

    2012-01-01

    The Astrophysics Source Code Library (ASCL), founded in 1999, is a free on-line registry for source codes of interest to astronomers and astrophysicists. The library is housed on the discussion forum for Astronomy Picture of the Day (APOD) and can be accessed at http://ascl.net. The ASCL has a comprehensive listing that covers a significant number of the astrophysics source codes used to generate results published in or submitted to refereed journals and continues to grow. The ASCL currently has entries for over 500 codes; its records are citable and are indexed by ADS. The editors of the ASCL and members of its Advisory Committee were on hand at a demonstration table in the ADASS poster room to present the ASCL, accept code submissions, show how the ASCL is starting to be used by the astrophysics community, and take questions on and suggestions for improving the resource.

  3. Studies on seismic source

    Institute of Scientific and Technical Information of China (English)

    李世愚; 陈运泰

    2003-01-01

    During the period of 1999~2002, the Chinese seismologists made a serious of developments in the study on seismic sources including observations, experiments and theory. In the field of observation, the methods of the accuracy location of earthquake sources, the inversion of seismic moment tensor and the mechanism of earthquake source are improved and developed. A lot of important earthquake events are studied by using these methods. The rupture processes of these events are inverted and investigated combined with the local stress fields and the tectonic moment by using the measurements of surface deformation. In the fields of experiments and theory, many developments are obtained in cause of seismic formation, condition of stress and tectonics, dynamics of earthquake rupture, rock fracture and nucleation of strong earthquakes.

  4. Optical source transformations.

    Science.gov (United States)

    Kundtz, N; Roberts, D A; Allen, J; Cummer, S; Smith, D R

    2008-12-22

    Transformation optics is a recently appreciated methodology for the design of complex media that control the propagation of electromagnetic and other types of waves. The transformation optical technique involves the use of coordinate transformations applied to some region of space, providing a conceptual means to redirect the flow of waves. Successfully designed devices to date have made use of transformations acting on passive space only; however, the technique can also be applied when source distributions (e.g., current and charge) are included within the space being transformed. In this paper we present examples of source transformations that illustrate the potential of these expanded transformation optical methods. In particular, using finite-element full-wave simulations, we confirm the restoration of dipole radiation patterns from both a distorted 'pin-wheel' antenna and a bent dipole partially occluded by a cylindrical scatterer. We propose the technique of source transformations as a powerful approach for antenna design, especially in relation to conformal antennas.

  5. INEEL Source Water Assessment

    Energy Technology Data Exchange (ETDEWEB)

    Sehlke, Gerald

    2003-03-01

    The Idaho National Engineering and Environmental Laboratory (INEEL) covers approximately 890 mi2 and includes 12 public water systems that must be evaluated for Source water protection purposes under the Safe Drinking Water Act. Because of its size and location, six watersheds and five aquifers could potentially affect the INEEL’s drinking water sources. Based on a preliminary evaluation of the available information, it was determined that the Big Lost River, Birch Creek, and Little Lost River Watersheds and the eastern Snake River Plain Aquifer needed to be assessed. These watersheds were delineated using the United States Geologic Survey’s Hydrological Unit scheme. Well capture zones were originally estimated using the RESSQC module of the Environmental Protection Agency’s Well Head Protection Area model, and the initial modeling assumptions and results were checked by running several scenarios using Modflow modeling. After a technical review, the resulting capture zones were expanded to account for the uncertainties associated with changing groundwater flow directions, a thick vadose zone, and other data uncertainties. Finally, all well capture zones at a given facility were merged to a single wellhead protection area at each facility. A contaminant source inventory was conducted, and the results were integrated with the well capture zones, watershed and aquifer information, and facility information using geographic information system technology to complete the INEEL’s Source Water Assessment. Of the INEEL’s 12 public water systems, three systems rated as low susceptibility (EBR-I, Main Gate, and Gun Range), and the remainder rated as moderate susceptibility. No INEEL public water system rated as high susceptibility. We are using this information to develop a source water management plan from which we will subsequently implement an INEEL-wide source water management program. The results are a very robust set of wellhead protection areas that will

  6. Hahmosuunnittelu Source Engine -pelimoottorille

    OpenAIRE

    Korpilaakso, Joonas

    2010-01-01

    Tämän opinnäytetyön tarkoitus oli tutkia videopelien hahmosuunnittelua nykypäivänä ja selvittää mitä eri työvaiheita hahmosuunnittelu pitää sisällään sekä suunnitella ja toteuttaa pelihahmo Source Engine-pelimoottorille. Tutkimusten pohjalta suunniteltiin pelihahmo Valve Softwaren kehittämälle Source Engine-pelimoottorille. Hahmo suunniteltiin Half-Life 2-pelin modifikaatioon ”The Keep”, jonka tarinan ympärille hahmo rakennettiin. Työn tavoitteena oli suunnitella ja toteuttaa pelihahmo, joka ...

  7. Valorization of ECR sources

    CERN Document Server

    2003-01-01

    One way to limit the size of particle accelerators is to use intense multicharged ion beams. Thus, compact, low cost and reliable sources have been developed. These sources are based on the electron cyclotron resonance (ECR) principle and need no cathode nor filament. A prototype named Nanogan has been developed for the Spiral project of the Ganil accelerator (Caen, France). Then, this technology has been transferred toward other research domains and industrial applications, like the ion implantation in micro-electronics components. (J.S.)

  8. Sources of Financial Sociability

    DEFF Research Database (Denmark)

    Thompson, Grahame

    2011-01-01

    of the article which is to explore further the nature of ‘irrationality’ as manifest in financial crises. When the contours of both these aspects of financial calculation have been elaborated, the article moves on to consider how they might shape regulatory responses to the seeming inevitability of financial......This article investigates the sources of sociability in modern financial systems as a prelude to assessing the prospects for financial regulation. Three sources are identified: sociality dependent upon contract, upon relational interdependency, and upon the operation of will and passion. Each...

  9. OLED area illumination source

    Science.gov (United States)

    Foust, Donald Franklin; Duggal, Anil Raj; Shiang, Joseph John; Nealon, William Francis; Bortscheller, Jacob Charles

    2008-03-25

    The present invention relates to an area illumination light source comprising a plurality of individual OLED panels. The individual OLED panels are configured in a physically modular fashion. Each OLED panel comprising a plurality of OLED devices. Each OLED panel comprises a first electrode and a second electrode such that the power being supplied to each individual OLED panel may be varied independently. A power supply unit capable of delivering varying levels of voltage simultaneously to the first and second electrodes of each of the individual OLED panels is also provided. The area illumination light source also comprises a mount within which the OLED panels are arrayed.

  10. Alternative Energy Sources

    CERN Document Server

    Michaelides, Efstathios E (Stathis)

    2012-01-01

    Alternative Energy Sources is designed to give the reader, a clear view of the role each form of alternative energy may play in supplying the energy needs of the human society in the near and intermediate future (20-50 years).   The two first chapters on energy demand and supply and environmental effects, set the tone as to why the widespread use of alternative energy is essential for the future of human society. The third chapter exposes the reader to the laws of energy conversion processes, as well as the limitations of converting one energy form to another. The sections on exergy give a succinct, quantitative background on the capability/potential of each energy source to produce power on a global scale. The fourth, fifth and sixth chapters are expositions of fission and fusion nuclear energy. The following five chapters (seventh to eleventh) include detailed descriptions of the most common renewable energy sources – wind, solar, geothermal, biomass, hydroelectric – and some of the less common sources...

  11. Open Source Software Acquisition

    DEFF Research Database (Denmark)

    Holck, Jesper; Kühn Pedersen, Mogens; Holm Larsen, Michael

    2005-01-01

    Lately we have seen a growing interest from both public and private organisations to adopt OpenSource Software (OSS), not only for a few, specific applications but also on a more general levelthroughout the organisation. As a consequence, the organisations' decisions on adoption of OSS arebecoming...

  12. Pulsed Plasma Electron Sources

    Science.gov (United States)

    Krasik, Yakov

    2008-11-01

    Pulsed (˜10-7 s) electron beams with high current density (>10^2 A/cm^2) are generated in diodes with electric field of E > 10^6 V/cm. The source of electrons in these diodes is explosive emission plasma, which limits pulse duration; in the case E Hadas and Ya. E. Krasik, Europhysics Lett. 82, 55001 (2008).

  13. International Entrepreneurship and Sourcing

    DEFF Research Database (Denmark)

    Servais, Per; Zucchella, Antonella; Palamera, Giada

    2006-01-01

    This contribution focuses on international sourcing as an entrepreneurial act and aims at demonstrating that it is actually at the core of internationalization processes of small firms, both established and international new ventures. Another issue of this research is to understand how these firm...

  14. Open source development

    DEFF Research Database (Denmark)

    Ulhøi, John Parm

    2004-01-01

    This paper addresses innovations based on open source or non-proprietary knowledge. Viewed through the lens of private property theory, such agency appears to be a true anomaly. However, by a further turn of the theoretical kaleidoscope, we will show that there may be perfectly justifiable reason...

  15. Environmental lichenology: Biomonitoring trace-element air pollution

    Energy Technology Data Exchange (ETDEWEB)

    Sloof, J.E.

    1993-09-27

    Chapter 1 describes the possibilities to study trace-element air pollution in order to get insight in the character and element levels of such pollution. Chapter 2 describes two monitoring surveys using Parmelia sulcata Taylor on a national scale, in which spatial and temporal patterns of heavy metals were investigated. The surveys were carried out in 1982-1983 at 110 sampling sites and in 1986-1987 at 210 sampling sites. From these studies it was concluded that lichens are at least good qualitative biomonitors for atmospheric trace-element levels. Chapter 3 describes the response of lichens to the cesium-137 activity as a result of the Chernobyl accident, deposited by rainfall in the Netherlands. From this study it was concluded that lichens are good biomonitors for atmospheric cesium-137 activity too. Chapter 4 describes the application of factor analysis to a lichen data set from a monitoring survey on a national scale (1986-1987), for source apportionment. In Chapter 5 a field study is described on the contribution of a possible influence from the soil to element concentrations in Parmelia sulcata Taylor growing on trees in a an area with polluted soil. Chapter 6 describes a field study on the interchangeability of two tolerant lichen species (Parmelia sulcata Taylor and Lecanora conizaeoides Nyl.) in a polluted area. In Chapter 7 a field study is described in which the quantitative relationships between concentrations of cobalt, scandium and zinc in lichens and concentrations in air particulate matter and total deposition (wet and dry) were investigated. Chapter 8 describes a laboratory study on the kinetics of the uptake-and release of cadmium in a green algae species (Selenastrum capricornutum Printz), which is regarded to be representative for the algal symboint in the lichens used in this thesis. Chapter 9 presents the central conclusions of this thesis for the lichen species, elements and conditions under study. (orig./MG).

  16. Cobalt source calibration

    Energy Technology Data Exchange (ETDEWEB)

    Rizvi, H.M.

    1999-12-03

    The data obtained from these tests determine the dose rate of the two cobalt sources in SRTC. Building 774-A houses one of these sources while the other resides in room C-067 of Building 773-A. The data from this experiment shows the following: (1) The dose rate of the No.2 cobalt source in Building 774-A measured 1.073 x 10{sup 5} rad/h (June 17, 1999). The dose rate of the Shepherd Model 109 Gamma cobalt source in Building 773-A measured 9.27 x 10{sup 5} rad/h (June 25, 1999). These rates come from placing the graduated cylinder containing the dosimeter solution in the center of the irradiation chamber. (2) Two calibration tests in the 774-A source placed the graduated cylinder with the dosimeter solution approximately 1.5 inches off center in the axial direction. This movement of the sample reduced the measured dose rate 0.92% from 1.083 x 10{sup 5} rad/h to 1.073 x 10{sup 5} rad/h. and (3) A similar test in the cobalt source in 773-A placed the graduated cylinder approximately 2.0 inches off center in the axial direction. This change in position reduced the measured dose rate by 10.34% from 1.036 x 10{sup 6} to 9.27 x 10{sup 5}. This testing used chemical dosimetry to measure the dose rate of a radioactive source. In this method, one determines the dose by the chemical change that takes place in the dosimeter. For this calibration experiment, the author used a Fricke (ferrous ammonium sulfate) dosimeter. This solution works well for dose rates to 10{sup 7} rad/h. During irradiation of the Fricke dosimeter solution the Fe{sup 2+} ions ionize to Fe{sup 3+}. When this occurs, the solution acquires a slightly darker tint (not visible to the human eye). To determine the magnitude of the change in Fe ions, one places the solution in an UV-VIS Spectrophotometer. The UV-VIS Spectrophotometer measures the absorbency of the solution. Dividing the absorbency by the total time (in minutes) of exposure yields the dose rate.

  17. Advanced Light Source

    Energy Technology Data Exchange (ETDEWEB)

    Sah, R.C.

    1983-03-01

    The Advanced Light Source (ALS) is a new synchrotron radiation source which has been proposed by Lawrence Berkeley Laboratory. The ALS will be a key component in a major new research facility, the National Center for Advanced Materials. The ALS will consist of an electron linear accelerator, a booster synchrotron, a 1.3-GeV electron storage ring, and a number of photon beam lines. Most or all photon beam lines will originate from wiggler and undulator magnets placed in the 12 long straight sections of the ALS. A very low electron beam emittance will provide photon beams of unsurpassed spectral brilliance from specially-designed undulators, and a high radiofrequency will produce very short pulse lengths.

  18. Open Source Physics

    CERN Document Server

    Wee, Loo Kang

    2013-01-01

    Open Source Physics (Brown, 2012; Christian, 2010; Esquembre, 2012; Hwang, 2010) empowers teachers and students to create and use these free tools with the associated intellectual property rights given to customise (Wee & Mak, 2009) the computer models/tools to suit their teaching and learning needs. Open Source Physics (OSP) focuses on design of computer models, such as Easy Java Simulations (EJS) and the use of video modeling and analysis (Tracker). They allow students to investigate, explore and analyse data which is either real or simulated. The OSP approach helps users overcome barriers in creating, using and scaling up meaningful ICT use in education. In Singapore, teachers and students have created or customised existing computer models to design and re-purpose EJS models to suit their context and learning needs. Tracker tools allow students to analyse different aspects of a physics phenomena to deepen their understanding of abstract physics concepts. Using Tracker, students record the motion of ob...

  19. Filtered cathodic arc source

    Science.gov (United States)

    Falabella, Steven; Sanders, David M.

    1994-01-01

    A continuous, cathodic arc ion source coupled to a macro-particle filter capable of separation or elimination of macro-particles from the ion flux produced by cathodic arc discharge. The ion source employs an axial magnetic field on a cathode (target) having tapered sides to confine the arc, thereby providing high target material utilization. A bent magnetic field is used to guide the metal ions from the target to the part to be coated. The macro-particle filter consists of two straight solenoids, end to end, but placed at 45.degree. to one another, which prevents line-of-sight from the arc spot on the target to the parts to be coated, yet provides a path for ions and electrons to flow, and includes a series of baffles for trapping the macro-particles.

  20. Background sources at PEP

    Energy Technology Data Exchange (ETDEWEB)

    Lynch, H.; Schwitters, R.F.; Toner, W.T.

    1988-01-01

    Important sources of background for PEP experiments are studied. Background particles originate from high-energy electrons and positrons which have been lost from stable orbits, ..gamma..-rays emitted by the primary beams through bremsstrahlung in the residual gas, and synchrotron radiation x-rays. The effect of these processes on the beam lifetime are calculated and estimates of background rates at the interaction region are given. Recommendations for the PEP design, aimed at minimizing background are presented. 7 figs., 4 tabs.

  1. Feed sources for livestock

    OpenAIRE

    Zanten, van, H.H.E.

    2016-01-01

    Production of food has re-emerged at the top of the global political agenda, driven by two contemporary challenges: the challenge to produce enough nutritious food to feed a growing and more prosperous human population, and the challenge to produce this food in an environmentally sustainable way. Current levels of production of especially animal-source food (ASF), pose severe pressure on the environment via their emissions to air, water, and soil; and their use of scarce resources, such as la...

  2. Stutter seismic source

    Energy Technology Data Exchange (ETDEWEB)

    Gumma, W. H.; Hughes, D. R.; Zimmerman, N. S.

    1980-08-12

    An improved seismic prospecting system comprising the use of a closely spaced sequence of source initiations at essentially the same location to provide shorter objective-level wavelets than are obtainable with a single pulse. In a preferred form, three dynamite charges are detonated in the same or three closely spaced shot holes to generate a downward traveling wavelet having increased high frequency content and reduced content at a peak frequency determined by initial testing.

  3. Y-source inverter

    DEFF Research Database (Denmark)

    Siwakoti, Yam P.; Town, Graham; Loh, Poh Chiang;

    2014-01-01

    This paper introduces a new 3-phase Y-source inverter whose gain is presently not matched by classical impedance-network-based inverters operating at the same duty ratio. The proposed network uses a tightly coupled transformer with three windings. By squeezing the shoot-through range while keeping....... This design flexibility was proven mathematically, and is supported by simulations carried out to prove the concept and validate the analysis....

  4. Coded source neutron imaging

    Energy Technology Data Exchange (ETDEWEB)

    Bingham, Philip R [ORNL; Santos-Villalobos, Hector J [ORNL

    2011-01-01

    Coded aperture techniques have been applied to neutron radiography to address limitations in neutron flux and resolution of neutron detectors in a system labeled coded source imaging (CSI). By coding the neutron source, a magnified imaging system is designed with small spot size aperture holes (10 and 100 m) for improved resolution beyond the detector limits and with many holes in the aperture (50% open) to account for flux losses due to the small pinhole size. An introduction to neutron radiography and coded aperture imaging is presented. A system design is developed for a CSI system with a development of equations for limitations on the system based on the coded image requirements and the neutron source characteristics of size and divergence. Simulation has been applied to the design using McStas to provide qualitative measures of performance with simulations of pinhole array objects followed by a quantitative measure through simulation of a tilted edge and calculation of the modulation transfer function (MTF) from the line spread function. MTF results for both 100um and 10um aperture hole diameters show resolutions matching the hole diameters.

  5. Coded source neutron imaging

    Science.gov (United States)

    Bingham, Philip; Santos-Villalobos, Hector; Tobin, Ken

    2011-03-01

    Coded aperture techniques have been applied to neutron radiography to address limitations in neutron flux and resolution of neutron detectors in a system labeled coded source imaging (CSI). By coding the neutron source, a magnified imaging system is designed with small spot size aperture holes (10 and 100μm) for improved resolution beyond the detector limits and with many holes in the aperture (50% open) to account for flux losses due to the small pinhole size. An introduction to neutron radiography and coded aperture imaging is presented. A system design is developed for a CSI system with a development of equations for limitations on the system based on the coded image requirements and the neutron source characteristics of size and divergence. Simulation has been applied to the design using McStas to provide qualitative measures of performance with simulations of pinhole array objects followed by a quantitative measure through simulation of a tilted edge and calculation of the modulation transfer function (MTF) from the line spread function. MTF results for both 100μm and 10μm aperture hole diameters show resolutions matching the hole diameters.

  6. SPIRE Point Source Photometry

    CERN Document Server

    Pearson, Chris; North, Chris; Bendo, George; Conversi, Luca; Dowell, Darren; Griffin, Matt; Jin, Terry; Laporte, Nicolas; Papageorgiou, Andreas; Schulz, Bernhard; Shupe, Dave; Smith, Anthony J; Xu, Kevin

    2014-01-01

    The different algorithms appropriate for point source photometry on data from the SPIRE instrument on-board the Herschel Space Observatory, within the Herschel Interactive Processing Environment (HIPE) are compared. Point source photometry of a large ensemble of standard calibration stars and dark sky observations is carried out using the 4 major methods within HIPE: SUSSEXtractor, DAOphot, the SPIRE Timeline Fitter and simple Aperture Photometry. Colour corrections and effective beam areas as a function of the assumed source spectral index are also included to produce a large number of photometric measurements per individual target, in each of the 3 SPIRE bands (250, 350, 500um), to examine both the accuracy and repeatability of each of the 4 algorithms. It is concluded that for flux densities down to the level of 30mJy that the SPIRE Timeline Fitter is the method of choice. However, at least in the 250 and 350um bands, all 4 methods provide photometric repeatability better than a few percent down to at appr...

  7. Future Synchrotron Radiation Sources

    CERN Document Server

    Winick, Herman

    2003-01-01

    Sources of synchrotron radiation (also called synchrotron light) and their associated research facilities have experienced a spectacular growth in number, performance, and breadth of application in the past two to three decades. In 1978 there were eleven electron storage rings used as light sources. Three of these were small rings, all below 500 mega-electron volts (MeV), dedicated to this purpose; the others, with energy up to 5 giga-electron volts (GeV), were used parasitically during the operation of the ring for high energy physics research. In addition, at that time synchrotron radiation from nine cyclic electron synchrotrons, with energy up to 5 GeV, was also used parasitically. At present no cyclic synchrotrons are used, while about 50 electron storage rings are in operation around the world as fully dedicated light sources for basic and applied research in a wide variety of fields. Among these fields are structural molecular biology, molecular environmental science, materials, analytic chemistry, micr...

  8. Radiation protection in medical centers : teletherapy service; Proteccion radiologica en centros hospitalarios : servicio de teleterapia

    Energy Technology Data Exchange (ETDEWEB)

    Resendiz G, G.; Perez P, M.; Figueroa M, E. [Clinica Medica Sur, Servicio de Radioterapia, Puente de Piedra No. 150, Col. Toriello Guerra, Mexico 14050 D. F. (Mexico)

    2008-12-15

    The General Regulation of Radiation Safety, it clearly provides the classification, requirements and obligations of the various figures relating to a radiation protection system, i.e., the occupationally exposed personnel, the radiation safety responsible, the legal representative, the type of installation, etc. For new installations, the shieldings calculation should be contained in the analytical report with due consideration of factors, such as those surrounding the areas classification based on the occupation type, the work load of the equipment and others. The operation license involves requirements such as the Report and the Radiation Safety Handbook, the Emergencies Plan, the establishment of register levels, investigation and intervention, the way it is carried out medical surveillance of the occupationally exposed personnel, and the description of the protection mechanisms and detection instrumentation and radiation measurement. Deserves mention the case when high readings are recorded in the personal dosimeters, which must submit to an interrogation to the employee, you must determine if it is an incorrect reading to the service provider, you must perform a medical exam blood cell count with relevant to the dose determination, may eventually can lead to a cytogenetic study and the determination to do if confirmed an unexpectedly high dose. Moreover, the technology evolution also implies the development of adaptation measures. For example, the Intensity Modulated Radiation Therapy, which is an advanced high-precision radiotherapy that uses X-ray accelerators for computer-controlled radiation doses precisely to a malignant tumor or specific areas within the tumor, taking into account requires regard to equipment, and space and shielding, time and staff hours for treatment, personnel training, materials for making images (such as two-dimensional arrangements of integrated circuits or diodes, films or portal images), the attention given by the engineers of service, the validation of the treatment plan and quality control of the planning system and dosimetry parameters and mechanics. (Author)

  9. Relics of Double Radio Sources

    CERN Document Server

    Dwarakanath, K S

    2009-01-01

    We have formed a new sample which consists of extended extragalactic radio sources without obvious active galactic nuclei (AGN) in them. Most of these sources appear to be dead double radio sources. These sources with steep spectra ($\\alpha < $ -1.8; S $\\propto \

  10. Source Monitoring in Alzheimer's Disease

    Science.gov (United States)

    El Haj, Mohamad; Fasotti, Luciano; Allain, Philippe

    2012-01-01

    Source monitoring is the process of making judgments about the origin of memories. There are three categories of source monitoring: reality monitoring (discrimination between self- versus other-generated sources), external monitoring (discrimination between several external sources), and internal monitoring (discrimination between two types of…

  11. Online Sources of Competitive Intelligence.

    Science.gov (United States)

    Wagers, Robert

    1986-01-01

    Presents an approach to using online sources of information for competitor intelligence (i.e., monitoring industry and tracking activities of competitors); identifies principal sources; and suggests some ways of making use of online databases. Types and sources of information and sources and database charts are appended. Eight references are…

  12. API Global Sourcing Strategies 2010.

    Science.gov (United States)

    Bennett, Shannon

    2010-09-01

    The API Global Sourcing Strategies 2010 Conference, held in Berlin, included topics covering new developments in the field of global sourcing of active pharmaceutical ingredients (APIs). This conference report highlights selected presentations on development in Eastern API markets, specifically India and China, factors influencing changes in global API sourcing, and risk mitigation in API sourcing.

  13. Point Source Extraction with MOPEX

    CERN Document Server

    Marleau, D M F R

    2005-01-01

    MOPEX (MOsaicking and Point source EXtraction) is a package developed at the Spitzer Science Center for astronomical image processing. We report on the point source extraction capabilities of MOPEX. Point source extraction is implemented as a two step process: point source detection and profile fitting. Non-linear matched filtering of input images can be performed optionally to increase the signal-to-noise ratio and improve detection of faint point sources. Point Response Function (PRF) fitting of point sources produces the final point source list which includes the fluxes and improved positions of the point sources, along with other parameters characterizing the fit. Passive and active deblending allows for successful fitting of confused point sources. Aperture photometry can also be computed for every extracted point source for an unlimited number of aperture sizes. PRF is estimated directly from the input images. Implementation of efficient methods of background and noise estimation, and modified Simplex a...

  14. SYNCHROTRON RADIATION SOURCES

    Energy Technology Data Exchange (ETDEWEB)

    HULBERT,S.L.; WILLIAMS,G.P.

    1998-07-01

    Synchrotron radiation is a very bright, broadband, polarized, pulsed source of light extending from the infrared to the x-ray region. It is an extremely important source of Vacuum Ultraviolet radiation. Brightness is defined as flux per unit area per unit solid angle and is normally a more important quantity than flux alone particularly in throughput limited applications which include those in which monochromators are used. It is well known from classical theory of electricity and magnetism that accelerating charges emit electromagnetic radiation. In the case of synchrotron radiation, relativistic electrons are accelerated in a circular orbit and emit electromagnetic radiation in a broad spectral range. The visible portion of this spectrum was first observed on April 24, 1947 at General Electric's Schenectady facility by Floyd Haber, a machinist working with the synchrotron team, although the first theoretical predictions were by Lienard in the latter part of the 1800's. An excellent early history with references was presented by Blewett and a history covering the development of the utilization of synchrotron radiation was presented by Hartman. Synchrotron radiation covers the entire electromagnetic spectrum from the infrared region through the visible, ultraviolet, and into the x-ray region up to energies of many 10's of kilovolts. If the charged particles are of low mass, such as electrons, and if they are traveling relativistically, the emitted radiation is very intense and highly collimated, with opening angles of the order of 1 milliradian. In electron storage rings there are three possible sources of synchrotron radiation; dipole (bending) magnets; wigglers, which act like a sequence of bending magnets with alternating polarities; and undulators, which are also multi-period alternating magnet systems but in which the beam deflections are small resulting in coherent interference of the emitted light.

  15. A New Energy Source

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Foreign energy companies are flocking to China to participate in the development of a potentially meaningful new energy source, coalbed methane, which is found in coal deposits. China United Coalbed Methane Co. Ltd. signed a contract with U.S.-based Orion Energy International Inc. on April 5 to jointly exploit the resource in the Sanjiao region of coal-rich Shanxi Province. Covering an area of some 462 square km, Sanjiao is home to rich coalbed methane reserves with thick, multi-level coalbeds that have ...

  16. Organizing for Global Sourcing

    DEFF Research Database (Denmark)

    Bals, Lydia; Turkulainen, Virpi

    Research on Purchasing Organization is dominated by studies on centralization versus decentralization. While global sourcing relates to the integrated activities of purchasing and other functions in line with the company’s strategic objectives and while it has been put forward that hybrid...... organizations are on the rise, the exact ways in which companies employ hybrid organizations in this context have not been studied in further detail. By presenting a multi-year case study from 2010 to 2013 at a pharmaceutical company, we elaborate on the existing knowledge regarding hybrid organizations...

  17. Accessing vs Sourcing Knowledge

    DEFF Research Database (Denmark)

    Awate, Snehal; Larsen, Marcus M.; Mudambi, Ram

    2015-01-01

    Research and development (R&D) internationalization is on the rise for advanced economy multinationals (AMNEs) as well as emerging economy multinationals (EMNEs). We study EMNE R&D internationalization by comparing it to that by AMNEs in the context of an emerging, knowledge-intensive industry. We...... to get on par with industry leaders. An in-depth comparison of knowledge flows reveals that within AMNEs, headquarters often serves the primary source of knowledge for R&D subsidiaries. In contrast, within EMNEs, headquarters accesses knowledge from R&D subsidiaries in advanced economies for innovation...

  18. Neutrinos from Auger Sources

    CERN Document Server

    Halzen, Francis

    2008-01-01

    The Pierre Auger observatory has presented evidence that the arrival directions of cosmic rays with energies in excess of 6x10^7 TeV may be correlated with nearby active galactic nuclei (AGN). In this context we revisit a suggestion based on gamma ray observations that nearby Fanaroff-Riley I galaxies such as Cen A and M87 are the sources of the local cosmic rays. We compute the accompanying neutrino flux and find a flux within reach of second-generation kilometer-scale neutrino telescopes.

  19. Compact synchrotron light sources

    CERN Document Server

    Weihreter, Ernst

    1996-01-01

    This book covers a new niche in circular accelerator design, motivated by the promising industrial prospects of recent micromanufacturing methods - X-ray lithography, synchrotron radiation-based micromachining and microanalysis techniques. It describes the basic concepts and the essential challenges for the development of compact synchrotron radiation sources from an accelerator designer's point of view and gives an outline of the actual state of the art. The volume is intended as an introduction and as a reference for physicists, engineers and managers involved in this rapidly developing fiel

  20. Variable leak gas source

    Science.gov (United States)

    Henderson, Timothy M.; Wuttke, Gilbert H.

    1977-01-01

    A variable leak gas source and a method for obtaining the same which includes filling a quantity of hollow glass micro-spheres with a gas, storing said quantity in a confined chamber having a controllable outlet, heating said chamber above room temperature, and controlling the temperature of said chamber to control the quantity of gas passing out of said controllable outlet. Individual gas filled spheres may be utilized for calibration purposes by breaking a sphere having a known quantity of a known gas to calibrate a gas detection apparatus.

  1. Data source handbook

    CERN Document Server

    Warden, Pete

    2011-01-01

    If you''re a developer looking to supplement your own data tools and services, this concise ebook covers the most useful sources of public data available today. You''ll find useful information on APIs that offer broad coverage, tie their data to the outside world, and are either accessible online or feature downloadable bulk data. You''ll also find code and helpful links. This guide organizes APIs by the subjects they cover-such as websites, people, or places-so you can quickly locate the best resources for augmenting the data you handle in your own service. Categories include: Website tools

  2. Sources of ISS

    Science.gov (United States)

    Goldreich, Peter

    1998-05-01

    Interstellar scintillations (ISS) of small angular diameter radio sources have been studied for 30 years. They arise from fluctuations of the interstellar electron density. These exhibit an anisotropic Kolmogorov spectrum over scales ranging from about 10(9) cm to 10(15) cm, with the power in these fluctuations varying by orders of magnitude from place to place. The optics of this phenomenon is fairly well understood. The same cannot be said for the physical process responsible for producing the electron density fluctuations. In recent work, Goldreich and Sridhar argue that incompressible MHD turbulence will produce a power law velocity spectrum of shear Alfven waves that matches the ISS electron density spectrum. The velocity spectrum arises from a critical balance between the linear wave periods and nonlinear wave interactions. Its connection to the electron density spectrum remains a puzzle. One might speculate that the turbulent velocity field mixes specific entropy as a passive contaminant thereby giving rise to isobaric temperature and density fluctuations whose spectra mimic that of the velocity field. This is the manner in which the atmospheric scintillations of optical stars arise. However, as a consequence of its rapid of cooling, specific entropy is not conserved in large scale motions of ionized interstellar gas. This severely limits the outer scale of the electron density spectrum. Implications of this limitation to potential sources and sites of ISS will be explored in this lecture.

  3. Online BCI with Stable Sources

    OpenAIRE

    2012-01-01

    In this paper, we show that the estimated intra-cranial sources using source localization on EEG signals can be used for online Brain Computer Interation (BCI) and the discriminant sources remain stable over days. Classifiers are trained on discriminant sources obtained for Error-related Potential (ErrP) based BCI on day 1 and then tested online on day 2. The results for nine subjects show that the source localization with discriminant sources can be used for online detection of ErrPs. Furthe...

  4. Filgrastim (Neupogen)

    Science.gov (United States)

    ... CRC) Simulation Tools Isotopes Americium-241 (Am-241) Cesium-137 (Cs-137) Radioisotope Brief Toxicology FAQs Cobalt- ... a drug that has been used successfully for cancer patients to stimulate the growth of the white ...

  5. Biological Effects of Protracted Exposure to Ionizing Radiation: Review, Analysis, and Model Development

    Science.gov (United States)

    1991-11-01

    aspect of fatigability associated with irradiated individuals makes any quantitative assessment difficult. However, victims of the Goiania Brazilian...from animal studies and preferably human experience; for example, the Goiania , Brazil accident involving protracted exposure to cesium-137 1-ray

  6. Food irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Webb, T.

    1986-01-01

    The proposed use of gamma radiation from cobalt 60 and cesium 137 for food irradiation in the United Kingdom is discussed, with particular reference to the possible dangers and disadvantages to the safety and wholesomeness of the food.

  7. Researchers scientific works of the Army health service during the year 1996; Travaux scientifiques des chercheurs du service de sante des armees durant l`annee 1996

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-12-31

    Nine articles are devoted to radiobiology. The consequences and biological effects of radiations at the cell level are studied here. The last articles is more specifically in relation with the decorporation of cesium 137. (N.C.)

  8. Nitride quantum light sources

    Science.gov (United States)

    Zhu, T.; Oliver, R. A.

    2016-02-01

    Prototype nitride quantum light sources, particularly single-photon emitters, have been successfully demonstrated, despite the challenges inherent in this complex materials system. The large band offsets available between different nitride alloys have allowed device operation at easily accessible temperatures. A wide range of approaches has been explored: not only self-assembled quantum dot growth but also lithographic methods for site-controlled nanostructure formation. All these approaches face common challenges, particularly strong background signals which contaminate the single-photon stream and excessive spectral diffusion of the quantum dot emission wavelength. If these challenges can be successfully overcome, then ongoing rapid progress in the conventional III-V semiconductors provides a roadmap for future progress in the nitrides.

  9. Perovskite photonic sources

    Science.gov (United States)

    Sutherland, Brandon R.; Sargent, Edward H.

    2016-05-01

    The field of solution-processed semiconductors has made great strides; however, it has yet to enable electrically driven lasers. To achieve this goal, improved materials are required that combine efficient (>50% quantum yield) radiative recombination under high injection, large and balanced charge-carrier mobilities in excess of 10 cm2 V-1 s-1, free-carrier densities greater than 1017 cm-3 and gain coefficients exceeding 104 cm-1. Solid-state perovskites are -- in addition to galvanizing the field of solar electricity -- showing great promise in photonic sources, and may be the answer to realizing solution-cast laser diodes. Here, we discuss the properties of perovskites that benefit light emission, review recent progress in perovskite electroluminescent diodes and optically pumped lasers, and examine the remaining challenges in achieving continuous-wave and electrically driven lasing.

  10. Swiss Light Source SLS

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-09-01

    The Paul Scherrer Institute has begun work on the implementation of the Swiss Synchrotron Light Source (SLS). The construction of this facility, which will have international scope, is intended to provide a national focus for co-operation between various disciplines and for research in material sciences. Although basic research in physics and chemistry, biology, medicine and environmental sciences would seem to be in the foreground, industrial users also have an interest in the SLS. At present, this mainly centres on investigations into the structure of biological and chemical molecules, the use of high-performance methods of analysis, and the manufacture and investigation of microstructures. SLS is planned to be taken into service with an initial experimental installation by the middle of 2001. In this brochure an overview is presented on the main characteristics of the SLS facility and on its significance as a tool for interdisciplinary research.

  11. Infrared source test

    Energy Technology Data Exchange (ETDEWEB)

    Ott, L.

    1994-11-15

    The purpose of the Infrared Source Test (IRST) is to demonstrate the ability to track a ground target with an infrared sensor from an airplane. The system is being developed within the Advance Technology Program`s Theater Missile Defense/Unmanned Aerial Vehicle (UAV) section. The IRST payload consists of an Amber Radiance 1 infrared camera system, a computer, a gimbaled mirror, and a hard disk. The processor is a custom R3000 CPU board made by Risq Modular Systems, Inc. for LLNL. The board has ethernet, SCSI, parallel I/O, and serial ports, a DMA channel, a video (frame buffer) interface, and eight MBytes of main memory. The real-time operating system VxWorks has been ported to the processor. The application code is written in C on a host SUN 4 UNIX workstation. The IRST is the result of a combined effort by physicists, electrical and mechanical engineers, and computer scientists.

  12. Neutrino Sources and Properties

    CERN Document Server

    Vissani, Francesco

    2014-01-01

    In this lecture, prepared for PhD students, basic considerations on neutrino interactions, properties and sites of production are overviewed. The detailed content is as follows: Sect. 1, Weak interactions and neutrinos: Fermi coupling; definition of neutrinos; global numbers. Sect. 2, A list of neutrino sources: Explanatory note and examples (solar pp- and supernova-neutrinos). Sect. 3, Neutrinos oscillations: Basic formalism (Pontecorvo); matter effect (Mikheev, Smirnov, Wolfenstein); status of neutrino masses and mixings. Sect. 4, Modifying the standard model to include neutrinos masses: The fermions of the standard model; one additional operator in the standard model (Weinberg); implications. One summary table and several exercises offer the students occasions to check, consolidate and extend their understanding; the brief reference list includes historical and review papers and some entry points to active research in neutrino physics.

  13. Large area plasma source

    Science.gov (United States)

    Foster, John (Inventor); Patterson, Michael (Inventor)

    2008-01-01

    An all permanent magnet Electron Cyclotron Resonance, large diameter (e.g., 40 cm) plasma source suitable for ion/plasma processing or electric propulsion, is capable of producing uniform ion current densities at its exit plane at very low power (e.g., below 200 W), and is electrodeless to avoid sputtering or contamination issues. Microwave input power is efficiently coupled with an ionizing gas without using a dielectric microwave window and without developing a throat plasma by providing a ferromagnetic cylindrical chamber wall with a conical end narrowing to an axial entrance hole for microwaves supplied on-axis from an open-ended waveguide. Permanent magnet rings are attached inside the wall with alternating polarities against the wall. An entrance magnet ring surrounding the entrance hole has a ferromagnetic pole piece that extends into the chamber from the entrance hole to a continuing second face that extends radially across an inner pole of the entrance magnet ring.

  14. Arsenic pollution sources.

    Science.gov (United States)

    Garelick, Hemda; Jones, Huw; Dybowska, Agnieszka; Valsami-Jones, Eugenia

    2008-01-01

    Arsenic is a widely dispersed element in the Earth's crust and exists at an average concentration of approximately 5 mg/kg. There are many possible routes of human exposure to arsenic from both natural and anthropogenic sources. Arsenic occurs as a constituent in more than 200 minerals, although it primarily exists as arsenopyrite and as a constituent in several other sulfide minerals. The introduction of arsenic into drinking water can occur as a result of its natural geological presence in local bedrock. Arsenic-containing bedrock formations of this sort are known in Bangladesh, West Bengal (India), and regions of China, and many cases of endemic contamination by arsenic with serious consequences to human health are known from these areas. Significant natural contamination of surface waters and soil can arise when arsenic-rich geothermal fluids come into contact with surface waters. When humans are implicated in causing or exacerbating arsenic pollution, the cause can almost always be traced to mining or mining-related activities. Arsenic exists in many oxidation states, with arsenic (III) and (V) being the most common forms. Similar to many metalloids, the prevalence of particular species of arsenic depends greatly on the pH and redox conditions of the matrix in which it exists. Speciation is also important in determining the toxicity of arsenic. Arsenic minerals exist in the environment principally as sulfides, oxides, and phosphates. In igneous rocks, only those of volcanic origin are implicated in high aqueous arsenic concentrations. Sedimentary rocks tend not to bear high arsenic loads, and common matrices such as sands and sandstones contain lower concentrations owing to the dominance of quartz and feldspars. Groundwater contamination by arsenic arises from sources of arsenopyrite, base metal sulfides, realgar and orpiment, arsenic-rich pyrite, and iron oxyhydroxide. Mechanisms by which arsenic is released from minerals are varied and are accounted for by

  15. Global Sourcing and Firm Selection

    DEFF Research Database (Denmark)

    Kohler, Wilhelm; Smolka, Marcel

    2014-01-01

    We analyze the sourcing strategies of firms active in the Spanish manufacturing sector. We show that firms that select strategies of vertical integration and of foreign sourcing ex post tend to have been more productive, ex ante, than other firms....

  16. CELESTIAL X-RAY SOURCES.

    Science.gov (United States)

    sources, (4) the physical conditions in the pulsating x-ray source in the Crab Nebula , and (5) miscellaneous related topics. A bibliography of all work performed under the contract is given. (Author)

  17. Region 9 Sole Source Aquifers

    Data.gov (United States)

    U.S. Environmental Protection Agency — There are 7 polygons representing 6 individual sole source aquifer boundaries and one streamflow source area in California, Arizona, and Nevada. Various efforts were...

  18. EV-GHG Mobile Source

    Data.gov (United States)

    U.S. Environmental Protection Agency — The EV-GHG Mobile Source Data asset contains measured mobile source GHG emissions summary compliance information on light-duty vehicles, by model, for certification...

  19. Sources for charged particles; Les sources de particules chargees

    Energy Technology Data Exchange (ETDEWEB)

    Arianer, J.

    1997-09-01

    This document is a basic course on charged particle sources for post-graduate students and thematic schools on large facilities and accelerator physics. A simple but precise description of the creation and the emission of charged particles is presented. This course relies on every year upgraded reference documents. Following relevant topics are considered: electronic emission processes, technological and practical considerations on electron guns, positron sources, production of neutral atoms, ionization, plasma and discharge, different types of positive and negative ion sources, polarized particle sources, materials for the construction of ion sources, low energy beam production and transport. (N.T.).

  20. Decommissioning of an irradiation unit

    Energy Technology Data Exchange (ETDEWEB)

    Richards, A.G. [Radiation Protection and Safety Services, Univ. of Leeds, Leeds (United Kingdom)

    2000-05-01

    Distributed throughout hospital, research establishments in the United Kingdom and many other countries are Irradiation Units and Teletherapy machines used for either research purposes or treatment of patients for radiotherapy. These Irradiation Units and Teletherapy machines are loaded with radioactive sources of either Cobalt 60 or Caesium 137. The activity of these sources can range from 1 Terabecquerel up to 100 Terabecquerels or more. Where it is possible to load the radioactive sources without removal from the shielded container into a transport package which is suitable for transport decommissioning of a Teletherapy machine is not a major exercise. When the radioactive sources need to be unloaded from the Irradiation Unit or Teletherapy machine the potential exists for very high levels of radiation. The operation outlined in the paper involved the transfer from an Irradiation Unit to a transport package of two 3.25 Terabecquerel sources of Cobalt 60. The operation of the removal and transfer comes within the scope of the United Kingdom Ionising Radiation Regulations 1985 which were made following the Recommendations of the International Commission on Radiological Protection. This paper illustrates a safe method for this operation and how doses received can be kept within ALARA. (author)

  1. Sensitivity of source apportionment results to mobile source profiles.

    Science.gov (United States)

    Cai, Tianqi; Schauer, James J; Huang, Wei; Fang, Dongqing; Shang, Jing; Wang, Yuqin; Zhang, Yuanxun

    2016-12-01

    The sensitivity of a source apportionment model to mobile source profiles was examined to determine the impact of using non-local mobile source profiles in chemical mass balance (CMB) models. We examined the impact of USA and Chinese mobile source profiles on source apportionment results in St. Louis, Missouri, and Beijing. The results showed that the use of non-local mobile source profiles did not impact the model apportionment results for vegetative detritus and biomass burning, but other primary source contributions were influenced by the use of non-local source profiles. Secondary organic carbon (SOC) contributions estimated by the CMB models with local and non-local profiles were compared to estimate of SOC from the EC tracer method and were found to be consistent with little bias. The results also showed that it is feasible to use the USA mobile profiles in China while model results were biased by using Chinese mobile profiles in the USA. Monthly and annual average concentrations of molecular markers in the source apportionment model showed lower sensitivity to source profiles than daily measurements, which has implications to the design of source apportionment studies.

  2. Convolutive Blind Source Separation Methods

    DEFF Research Database (Denmark)

    Pedersen, Michael Syskind; Larsen, Jan; Kjems, Ulrik

    2008-01-01

    During the past decades, much attention has been given to the separation of mixed sources, in particular for the blind case where both the sources and the mixing process are unknown and only recordings of the mixtures are available. In several situations it is desirable to recover all sources fro...

  3. Authorship Attribution of Source Code

    Science.gov (United States)

    Tennyson, Matthew F.

    2013-01-01

    Authorship attribution of source code is the task of deciding who wrote a program, given its source code. Applications include software forensics, plagiarism detection, and determining software ownership. A number of methods for the authorship attribution of source code have been presented in the past. A review of those existing methods is…

  4. Source-space ICA for MEG source imaging

    Science.gov (United States)

    Jonmohamadi, Yaqub; Jones, Richard D.

    2016-02-01

    Objective. One of the most widely used approaches in electroencephalography/magnetoencephalography (MEG) source imaging is application of an inverse technique (such as dipole modelling or sLORETA) on the component extracted by independent component analysis (ICA) (sensor-space ICA + inverse technique). The advantage of this approach over an inverse technique alone is that it can identify and localize multiple concurrent sources. Among inverse techniques, the minimum-variance beamformers offer a high spatial resolution. However, in order to have both high spatial resolution of beamformer and be able to take on multiple concurrent sources, sensor-space ICA + beamformer is not an ideal combination. Approach. We propose source-space ICA for MEG as a powerful alternative approach which can provide the high spatial resolution of the beamformer and handle multiple concurrent sources. The concept of source-space ICA for MEG is to apply the beamformer first and then singular value decomposition + ICA. In this paper we have compared source-space ICA with sensor-space ICA both in simulation and real MEG. The simulations included two challenging scenarios of correlated/concurrent cluster sources. Main Results. Source-space ICA provided superior performance in spatial reconstruction of source maps, even though both techniques performed equally from a temporal perspective. Real MEG from two healthy subjects with visual stimuli were also used to compare performance of sensor-space ICA and source-space ICA. We have also proposed a new variant of minimum-variance beamformer called weight-normalized linearly-constrained minimum-variance with orthonormal lead-field. Significance. As sensor-space ICA-based source reconstruction is popular in EEG and MEG imaging, and given that source-space ICA has superior spatial performance, it is expected that source-space ICA will supersede its predecessor in many applications.

  5. Economic explanations for concurrent sourcing

    DEFF Research Database (Denmark)

    Mols, Niels Peter

    2010-01-01

    Concurrent sourcing is a phenomenon where firms simultaneously make and buy the same good, i.e. they simultaneously use the governance modes of market and hierarchy. Though concurrent sourcing seems to be widespread, few studies of sourcing have focused on this phenomenon. This paper reviews diff...... different economic explanations for why firms use concurrent sourcing. The distinctive features of the explanations are compared, and it is discussed how they may serve as a springboard for research on concurrent sourcing. Managerial implications are also offered....

  6. Defining Open Source

    Directory of Open Access Journals (Sweden)

    Russ Nelson

    2007-09-01

    Full Text Available The Open Source Initiative and the Free Software Foundation share a common goal: that everyone should be free to modify and redistribute the software they commonly use. 'Should' is of course a normative word. For the FSF, 'should' is a moral imperative. Anything else is an immoral restriction on people's activities, just as are restrictions on speech, press, movement, and religion. For the OSI, freedom is a necessary precondition for a world where "software doesn't suck", in the words of a founder of the OSI. The FSF started from its founder's GNU Manifesto widely published in 1985. Given the manifesto's hostility to copyright, and given the failure of the Free Software Foundation to gain any traction amongst commercial users of software even with a 13-year head start, a group of people gathered together in 1998 to talk about a new strategy to get the corporate world to listen to hackers. They were impressed by Eric Raymond's Cathedral and the Bazaar's take-up among business leaders.

  7. Novel laser ion sources

    CERN Document Server

    Fournier, P; Kugler, H; Lisi, N; Scrivens, R; Rodríguez, F V; Düsterer, S; Sauerbrey, R; Schillinger, H; Theobald, W; Veisz, L; Tisch, J W G; Smith, R A

    2000-01-01

    Development in the field of high-power laser systems with repetition rates of several Hz and energies of few joules is highly active and opening, giving new possibilities for the design of laser ions sources. Preliminary investigations on the use of four different laser and target configurations are presented: (1) A small CO/sub 2/ laser (100 mJ, 10.6 mu m) focused onto a polyethylene target to produce C ions at 1 Hz repetition rate (CERN). (2) An excimer XeCl laser (6 J, 308 nm) focused onto solid targets (Frascati). (3) A femtosecond Ti: sapphire laser (250 mJ, 800 nm) directed onto a solid targets (Jena). (4) A picosecond Nd: yttrium-aluminum-garnet (0.3 J, 532 nm) focused into a dense medium of atomic clusters and onto solid targets (London). The preliminary experimental results and the most promising schemes will be discussed with respect to the scaling of the production of high numbers of highly charged ions. Different lasers are compared in terms of current density at 1 m distance for each charge state...

  8. Information Sources and Cartography

    Directory of Open Access Journals (Sweden)

    Nedjeljko Frančula

    2009-12-01

    Full Text Available The paper describes Internet information sources divided into following three groups: bibliographic databases, citation databases and databases with full texts including electronic journals. Bibliographic databases Bibliographia Cartographica, GEOPHOKA, Scopus and Current Contents (CC are analyzed concerning cartographic content representation. Searching the Current Contents database resulted in data about cartographers with more than 10 papers in CC journals. According to the Web of Science citation database, data are given about the most cited cartographers in papers published during the period between 1955 and the end of 2008 on the condition that each paper was cited at least once between 2000 and 2008. Data are also given about two most cited cartographic papers in the last 50 years. The PERO browser (web service of the Ruđer Bošković Institute was used to make a list of cartographic and related electronic journals and electronic versions of printed journals with full text available to Croatian academic and scientific community.

  9. Impurity sources in TEXTOR

    Science.gov (United States)

    Pospieszczyk, A.; Bay, H. L.; Bogen, P.; Hartwig, H.; Hintz, E.; Konen, L.; Ross, G. G.; Rusbuldt, D.; Samm, U.; Schweer, B.

    1987-02-01

    The deuterium, oxygen and carbon fluxes from the main limiter and the deuterium fluxes from the wall are measured in TEXTOR for an "all carbon" surrounding as a function of central density ne, of applied ICRH-power and of different wall conditions (carbonization). For this purpose, emission spectroscopy both with filter systems and spectrometers has been used. It is found that a major release mechanism for light impurities is via the formation of molecules. Oxygen seems to enter the discharge from the liner via O-D containing molecules, whereas the limiter acts as the main carbon source by the release of hydro-carbons as indicated by the observed CD-band spectra. Both oxygen and carbon fluxes are reduced by about a factor of two after a fresh carbonization. Above a certain critical density the plasma detaches from the limiter and forms a stable discharge with a radiation cooled boundary layer and with a major fraction of particles now reaching the wall instead of the limiter. The critical density rises with decreasing impurity fluxes or with increasing heating powers.

  10. Pi a source book

    CERN Document Server

    Berggren, Lennart; Borwein, Peter

    2004-01-01

    This book documents the history of pi from the dawn of mathematical time to the present. One of the beauties of the literature on pi is that it allows for the inclusion of very modern, yet accessible, mathematics. The articles on pi collected herein include selections from the mathematical and computational literature over four millennia, a variety of historical studies on the cultural significance of the number, and an assortment of anecdotal, fanciful, and simply amusing pieces. For this new edition, the authors have updated the original material while adding new material of historical and cultural interest. There is a substantial exposition of the recent history of the computation of digits of pi, a discussion of the normality of the distribution of the digits, new translations of works by Viete and Huygen, as well as Kaplansky's never-before-published "Song of Pi." From the reviews of earlier editions: "Few mathematics books serve a wider potential readership than does a source book and this particular on...

  11. Intense pulsed neutron source

    Science.gov (United States)

    The IPNS Progress Report 10th Anniversary Edition is being published in recognition of the first ten years of successful IPNS operation. To emphasize the significance of this milestone, we wanted this report to stand apart from the previous IPNS Progress Reports, and the best way to do this, we thought, was to make the design and organization of the report significantly different. In their articles, authors were asked to emphasize not only advances made since IPNS began operating but also the groundwork that was laid at its predecessor facilities - Argonne's ZING-P and ZING-P' prototype pulsed neutron sources and CP-5 reactor. Each article stands as a separate chapter in the report, since each represents a particular instrument or class of instruments, system, technique, or area of research. In some cases, contributions were similar to review articles in scientific journals, complete with extensive lists of references. Ten-year cumulative lists of members of IPNS committees and of scientists who have visited or done experiments at IPNS were assembled. A list of published and 'in press' articles in journals, books, and conference proceedings, resulting from work done at IPNS during the past ten years, was compiled. And archival photographs of people and activities during the ten-year history of IPNS were located and were used liberally throughout the report. The titles of the chapters in this report are: accelerator; computer; radiation effects; powder; stress; single crystal; superconductivity; amorphous; small angle; reflection; quasielastic; inelastic; inelastic magnetic; deep inelastic; user program; the future; and publications.

  12. Industrial ion sources broadbeam gridless ion source technology

    CERN Document Server

    Zhurin, Viacheslav V

    2012-01-01

    Due to the large number of uses of ion sources in academia and industry, those who utilize these sources need up to date and coherent information to keep themselves abreast of developments and options, and to chose ideal solutions for quality and cost-effectiveness. This book, written by an author with a strong industrial background and excellent standing, is the comprehensive guide users and developers of ion sources have been waiting for. Providing a thorough refresher on the physics involved, this resource systematically covers the source types, components, and the operational parameters.

  13. Maximum Likelihood Localization of Radiation Sources with unknown Source Intensity

    CERN Document Server

    Baidoo-Williams, Henry E

    2016-01-01

    In this paper, we consider a novel and robust maximum likelihood approach to localizing radiation sources with unknown statistics of the source signal strength. The result utilizes the smallest number of sensors required theoretically to localize the source. It is shown, that should the source lie in the open convex hull of the sensors, precisely $N+1$ are required in $\\mathbb{R}^N, ~N \\in \\{1,\\cdots,3\\}$. It is further shown that the region of interest, the open convex hull of the sensors, is entirely devoid of false stationary points. An augmented gradient ascent algorithm with random projections should an estimate escape the convex hull is presented.

  14. Disintegrins from Hematophagous Sources

    Directory of Open Access Journals (Sweden)

    Ivo M. B. Francischetti

    2012-04-01

    Full Text Available Bloodsucking arthropods are a rich source of salivary molecules (sialogenins which inhibit platelet aggregation, neutrophil function and angiogenesis. Here we review the literature on salivary disintegrins and their targets. Disintegrins were first discovered in snake venoms, and were instrumental in our understanding of integrin function and also for the development of anti-thrombotic drugs. In hematophagous animals, most disintegrins described so far have been discovered in the salivary gland of ticks and leeches. A limited number have also been found in hookworms and horseflies, and none identified in mosquitoes or sand flies. The vast majority of salivary disintegrins reported display a RGD motif and were described as platelet aggregation inhibitors, and few others as negative modulator of neutrophil or endothelial cell functions. This notably low number of reported disintegrins is certainly an underestimation of the actual complexity of this family of proteins in hematophagous secretions. Therefore an algorithm was created in order to identify the tripeptide motifs RGD, KGD, VGD, MLD, KTS, RTS, WGD, or RED (flanked by cysteines in sialogenins deposited in GenBank database. The search included sequences from various blood-sucking animals such as ticks (e.g., Ixodes sp., Argas sp., Rhipicephalus sp., Amblyomma sp., tabanids (e.g., Tabanus sp., bugs (e.g., Triatoma sp., Rhodnius prolixus, mosquitoes (e.g., Anopheles sp., Aedes sp., Culex sp., sand flies (e.g., Lutzomyia sp., Phlebotomus sp., leeches (e.g., Macrobdella sp., Placobdella sp. and worms (e.g., Ancylostoma sp.. This approach allowed the identification of a remarkably high number of novel putative sialogenins with tripeptide motifs typical of disintegrins (>450 sequences whose biological activity remains to be verified. This database is accessible

  15. Editorial: Open Source in Government

    Directory of Open Access Journals (Sweden)

    Dru Lavigne

    2009-04-01

    Full Text Available Last summer, the Center for Strategic and International Studies published the sixth update to their Open Source Policy survey. The survey "tracks governmental policies on the use of open source software as reported in the press or other media." The report lists 275 open source policy initiatives. It also breaks down by country and by government level whether the policy on the use of open source is considered to be advisory, preferential, or mandatory. The editorial theme for the May issue of the OSBR is "open source in government" and we are pleased that the authors have drawn upon their experiences to provide insight into public policy regarding open source for many parts of the world.

  16. Cluster banding heat source model

    Institute of Scientific and Technical Information of China (English)

    Zhang Liguo; Ji Shude; Yang Jianguo; Fang Hongyuan; Li Yafan

    2006-01-01

    Concept of cluster banding heat source model is put forward for the problem of overmany increment steps in the process of numerical simulation of large welding structures, and expression of cluster banding heat source model is deduced based on energy conservation law.Because the expression of cluster banding heat source model deduced is suitable for random weld width, quantitative analysis of welding stress field for large welding structures which have regular welds can be made quickly.

  17. Advanced Neutron Source (ANS) Project

    Science.gov (United States)

    Campbell, J. H.

    1992-01-01

    This report discusses the following about the Advanced Neutron Source: Project Management; Research and Development; Fuel Development; Corrosion Loop Tests and Analyses; Thermal-Hydraulic Loop Tests; Reactor Control and Shutdown Concepts; Critical and Subcritical Experiments; Material Data, Structural Tests, and Analysis; Cold-Source Development; Beam Tube, Guide, and Instrument Development; Hot-Source Development; Neutron Transport and Shielding; I & C Research and Development; Design; and Safety.

  18. Neutron imaging of radioactive sources

    Science.gov (United States)

    Hameed, F.; Karimzadeh, S.; Zawisky, M.

    2008-08-01

    Isotopic neutron sources have been available for more than six decades. At the Atomic Institute in Vienna, operating a 250 kW TRIGA reactor, different neutron sources are in use for instrument calibration and fast neutron applications but we have only little information about their construction and densities. The knowledge of source design is essential for a complete MCNP5 modeling of the experiments. Neutron radiography (NR) and neutron tomography (NT) are the best choices for the non-destructive inspection of the source geometry and homogeneity. From the transmission analysis we gain information about the shielding components and the densities of the radio-isotopes in the cores. Three neutron sources, based on (alpha, n) reaction, have been investigated, two 239PuBe sources and one 241AmBe source. In the NR images the internal structure was clearly revealed using high-resolving scintillation and imaging plate detectors. In one source tablet a crack was detected which causes asymmetric neutron emission. The tomography inspection of strong absorbing materials is more challenging due to the low beam intensity of 1.3x105 n/cm2s at our NT instrument, and due to the beam hardening effect which requires an extension of reconstruction software. The tomographic inspection of a PuBe neutron source and appropriate measures for background and beam hardening correction are presented.

  19. Animal models of source memory.

    Science.gov (United States)

    Crystal, Jonathon D

    2016-01-01

    Source memory is the aspect of episodic memory that encodes the origin (i.e., source) of information acquired in the past. Episodic memory (i.e., our memories for unique personal past events) typically involves source memory because those memories focus on the origin of previous events. Source memory is at work when, for example, someone tells a favorite joke to a person while avoiding retelling the joke to the friend who originally shared the joke. Importantly, source memory permits differentiation of one episodic memory from another because source memory includes features that were present when the different memories were formed. This article reviews recent efforts to develop an animal model of source memory using rats. Experiments are reviewed which suggest that source memory is dissociated from other forms of memory. The review highlights strengths and weaknesses of a number of animal models of episodic memory. Animal models of source memory may be used to probe the biological bases of memory. Moreover, these models can be combined with genetic models of Alzheimer's disease to evaluate pharmacotherapies that ultimately have the potential to improve memory.

  20. Ion source choices - an h- source for the high intensity neutrino source

    Energy Technology Data Exchange (ETDEWEB)

    Moehs, Douglas P.; /Fermilab; Welton, Robert F.; /SNS Project, Oak Ridge; Stockli, Martin P.; Peters, Jens; /DESY; Alessi, James; /Brookhaven

    2006-08-01

    The High Intensity Neutrino Source (HINS) program at Fermilab (formerly the Proton Driver) aims to develop a multi-mission linear accelerator (LINAC) capable of accelerate H{sup -} ions to 8 GeV. This paper touches on the ion source requirements for the HINS and discusses long pulse length testing of three ion sources which appear to have the capability of meeting these requirements.

  1. Faceted Taxonomy-Based Sources

    Science.gov (United States)

    Tzitzikas, Yannis

    The objective of this chapter is to explain the underlying mathematical structure of faceted taxonomy-based sources and to provide some common notions and notations that are used in some parts of the book. Subsequently, and on the basis of the introduced formalism, this chapter describes the interaction between a user and an information source that supports dynamic taxonomies and faceted search.

  2. Status of spallation neutron source

    Energy Technology Data Exchange (ETDEWEB)

    Oyama, Yukio [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    1997-03-01

    Existing and planned facilities using proton accelerator driven spallation neutron source are reviewed. These include new project of neutron science proposed from Japan Atomic Energy Research Institute. The present status of facility requirement and accelerator technology leads us to new era of neutron science such as neutron scattering research and nuclear transmutation study using very intense neutron source. (author)

  3. Urban Sources of Air Pollution

    DEFF Research Database (Denmark)

    Sorenson, Spencer C.

    1998-01-01

    A discusion of the relative importance of different mobile sources, effects of driving on emissions, history of emissions standards, and technological methods to reduce emissions.......A discusion of the relative importance of different mobile sources, effects of driving on emissions, history of emissions standards, and technological methods to reduce emissions....

  4. Hooded arc ion-source

    CERN Multimedia

    1972-01-01

    The positioning system for the hooded arc ion-source, shown prior to mounting, consists of four excentric shafts to locate the ion-source and central electrodes. It will be placed on the axis of the SC and introduced into the vacuum tank via the air locks visible in the foreground.

  5. Online Information Source & Access Method

    OpenAIRE

    2009-01-01

    Online resources play important role in research and development of the country. So, LIS professional are interested in accessing and guiding users and readers to all available information sources. This article highlighted and described the availability of online information sources, open access e-journals and its access method.

  6. Particle Acceleration in Astrophysical Sources

    CERN Document Server

    Amato, Elena

    2015-01-01

    Astrophysical sources are extremely efficient accelerators. Some sources emit photons up to multi-TeV energies, a signature of the presence, within them, of particles with energies much higher than those achievable with the largest accelerators on Earth. Even more compelling evidence comes from the study of Cosmic Rays, charged relativistic particles that reach the Earth with incredibly high energies: at the highest energy end of their spectrum, these subatomic particles are carrying a macroscopic energy, up to a few Joules. Here I will address the best candidate sources and mechanisms as cosmic particle accelerators. I will mainly focus on Galactic sources such as Supernova Remnants and Pulsar Wind Nebulae, which being close and bright, are the best studied among astrophysical accelerators. These sources are held responsible for most of the energy that is put in relativistic particles in the Universe, but they are not thought to accelerate particles up to the highest individual energies, $\\approx 10^{20}$ eV...

  7. Testing earthquake source inversion methodologies

    KAUST Repository

    Page, Morgan T.

    2011-01-01

    Source Inversion Validation Workshop; Palm Springs, California, 11-12 September 2010; Nowadays earthquake source inversions are routinely performed after large earthquakes and represent a key connection between recorded seismic and geodetic data and the complex rupture process at depth. The resulting earthquake source models quantify the spatiotemporal evolution of ruptures. They are also used to provide a rapid assessment of the severity of an earthquake and to estimate losses. However, because of uncertainties in the data, assumed fault geometry and velocity structure, and chosen rupture parameterization, it is not clear which features of these source models are robust. Improved understanding of the uncertainty and reliability of earthquake source inversions will allow the scientific community to use the robust features of kinematic inversions to more thoroughly investigate the complexity of the rupture process and to better constrain other earthquakerelated computations, such as ground motion simulations and static stress change calculations.

  8. Impedance source power electronic converters

    CERN Document Server

    Liu, Yushan; Ge, Baoming; Blaabjerg, Frede; Ellabban, Omar; Loh, Poh Chiang

    2016-01-01

    Impedance Source Power Electronic Converters brings together state of the art knowledge and cutting edge techniques in various stages of research related to the ever more popular impedance source converters/inverters. Significant research efforts are underway to develop commercially viable and technically feasible, efficient and reliable power converters for renewable energy, electric transportation and for various industrial applications. This book provides a detailed understanding of the concepts, designs, controls, and application demonstrations of the impedance source converters/inverters. Key features: Comprehensive analysis of the impedance source converter/inverter topologies, including typical topologies and derived topologies. Fully explains the design and control techniques of impedance source converters/inverters, including hardware design and control parameter design for corresponding control methods. Presents the latest power conversion solutions that aim to advance the role of pow...

  9. Source rock potential in Pakistan

    Energy Technology Data Exchange (ETDEWEB)

    Raza, H.A. (Hydrocarbon Development Institute of Pakistan, Islamabad (Pakistan))

    1991-03-01

    Pakistan contains two sedimentary basins: Indus in the east and Balochistan in the west. The Indus basin has received sediments from precambrian until Recent, albeit with breaks. It has been producing hydrocarbons since 1914 from three main producing regions, namely, the Potwar, Sulaisman, and Kirthar. In the Potwar, oil has been discovered in Cambrian, Permian, Jurassic, and Tertiary rocks. Potential source rocks are identified in Infra-Cambrian, Permian, Paleocene, and Eocene successions, but Paleocene/Eocene Patala Formation seems to be the main source of most of the oil. In the Sulaiman, gas has been found in Cretaceous and Tertiary; condensate in Cretaceous rocks. Potential source rocks are indicated in Cretaceous, Paleocene, and Eocene successions. The Sembar Formation of Early Cretaceous age appears to be the source of gas. In the Kirthar, oil and gas have been discovered in Cretaceous and gas has been discovered in paleocene and Eocene rocks. Potential source rocks are identified in Kirthar and Ghazij formations of Eocene age in the western part. However, in the easter oil- and gas-producing Badin platform area, Union Texas has recognized the Sembar Formation of Early Cretaceous age as the only source of Cretaceous oil and gas. The Balochistan basin is part of an Early Tertiary arc-trench system. The basin is inadequately explored, and there is no oil or gas discovery so far. However, potential source rocks have been identified in Eocene, Oligocene, Miocene, and Pliocene successions based on geochemical analysis of surface samples. Mud volcanoes are present.

  10. International Data on Radiological Sources

    Energy Technology Data Exchange (ETDEWEB)

    Martha Finck; Margaret Goldberg

    2010-07-01

    ABSTRACT The mission of radiological dispersal device (RDD) nuclear forensics is to identify the provenance of nuclear and radiological materials used in RDDs and to aid law enforcement in tracking nuclear materials and routes. The application of databases to radiological forensics is to match RDD source material to a source model in the database, provide guidance regarding a possible second device, and aid the FBI by providing a short list of manufacturers and distributors, and ultimately to the last legal owner of the source. The Argonne/Idaho National Laboratory RDD attribution database is a powerful technical tool in radiological forensics. The database (1267 unique vendors) includes all sealed sources and a device registered in the U.S., is complemented by data from the IAEA Catalogue, and is supported by rigorous in-lab characterization of selected sealed sources regarding physical form, radiochemical composition, and age-dating profiles. Close working relationships with global partners in the commercial sealed sources industry provide invaluable technical information and expertise in the development of signature profiles. These profiles are critical to the down-selection of potential candidates in either pre- or post- event RDD attribution. The down-selection process includes a match between an interdicted (or detonated) source and a model in the database linked to one or more manufacturers and distributors.

  11. Diversity employment and recruitment sources

    Energy Technology Data Exchange (ETDEWEB)

    1994-08-01

    Effective human resources management has been identified as one of four critical success factors in the Department of Energy Strategic Plan. The Plan states relative to this factor: ``The Department seeks greater alignment of resources with agency priorities and increased diversification of the workforce, including gender, ethnicity, age, and skills. This diversification will bring new thinking and perspectives that heretofore have not had a voice in departmental decision-making.`` This Guide has been developed as a key tool to assist Department of Energy management and administrative staff in achieving Goal 2 of this critical success factor, which is to ``Ensure a diverse and talented workforce.`` There are numerous sources from which to recruit minorities, women and persons with disabilities. Applying creativity and proactive effort, using traditional and non-traditional approaches, and reaching out to various professional, academic and social communities will increase the reservoir of qualified candidates from which to make selections. In addition, outreach initiatives will undoubtedly yield further benefits such as a richer cultural understanding and diversity awareness. The resource listings presented in this Guide are offered to encourage active participation in the diversity recruitment process. This Guide contains resource listings by state for organizations in the following categories: (1) African American Recruitment Sources; (2) Asian American/Pacific Islander Recruitment Sources; (3) Hispanic Recruitment Sources; (4) Native American/Alaskan Native Recruitment Sources; (5) Persons with Disabilities Recruitment Sources; and (6) Women Recruitment Sources.

  12. Spallation neutron source and other high intensity froton sources

    Energy Technology Data Exchange (ETDEWEB)

    Weiren Chou

    2003-02-06

    This lecture is an introduction to the design of a spallation neutron source and other high intensity proton sources. It discusses two different approaches: linac-based and synchrotron-based. The requirements and design concepts of each approach are presented. The advantages and disadvantages are compared. A brief review of existing machines and those under construction and proposed is also given. An R&D program is included in an appendix.

  13. Embedded EZ-Source Inverters

    DEFF Research Database (Denmark)

    Chiang Loh, Poh; Gao, Feng; Blaabjerg, Frede

    2010-01-01

    of embedded EZ-source inverters that can produce the same gain as the Z-source inverters but with smoother and smaller current/voltage maintained across the dc input source and within the impedance network. These latter features are attained without using any additional passive filter, which surely...... is a favorable advantage, since an added filter will raise the system cost and, at times, can complicate the dynamic tuning and resonant consideration of the inverters. The same embedded concept can also be used for designing a full range of voltage- and current-type inverters with each of them tested...

  14. Unimodular gravity with external sources

    CERN Document Server

    Álvarez, Enrique

    2012-01-01

    The only allowed source of the gravitational field in the unimodular theory, invariant under area-preserving (transverse) diffeomorphisms as well as Weyl transformations, is just the traceless piece of the energy-momentum tensor. This fact notwithstanding, the free energy produced by arbitrary sources (not only static ones) is identical to the one predicted by general relativity. This encompasses all weak field tests of gravitation. There is an important difference with general relativity though. A pure trace source, such as the one produced by a pure vacuum energy with frozen scalar field does not weigh at all. This sheds new light on the direct cosmological constant problem.

  15. Handbook of Open Source Tools

    CERN Document Server

    Koranne, Sandeep

    2011-01-01

    Handbook of Open Source Tools introduces a comprehensive collection of advanced open source tools useful in developing software applications. The book contains information on more than 200 open-source tools which include software construction utilities for compilers, virtual-machines, database, graphics, high-performance computing, OpenGL, geometry, algebra, graph theory , GUIs and more. Special highlights for software construction utilities and application libraries are included. Each tool is covered in the context of a real like application development setting. This unique handbook presents

  16. Source model for blasting vibration

    Institute of Scientific and Technical Information of China (English)

    DING; Hua(丁桦); ZHENG; Zhemin(郑哲敏)

    2002-01-01

    By analyzing and comparing the experimental data, the point source moment theory and the cavity theory, it is concluded that the vibrating signals away from the blasting explosive come mainly from the natural vibrations of the geological structures near the broken blasting area. The source impulses are not spread mainly by the inelastic properties (such as through media damping, as believed to be the case by many researchers) of the medium in the propagation pass, but by this structure. Then an equivalent source model for the blasting vibrations of a fragmenting blasting is proposed, which shows the important role of the impulse of the source's time function under certain conditions. For the purpose of numerical simulation, the model is realized in FEM, The finite element results are in good agreement with the experimental data.

  17. Data Sources for the Analyses

    Data.gov (United States)

    U.S. Environmental Protection Agency — Links are provided for the National Wetlands Inventory, National Hydrography Dataset, and the WorldClim-Global Climate Data source data websites This dataset is...

  18. Intermediate-energy light sources

    CERN Document Server

    Corbett, W

    2003-01-01

    Increasingly, atomic scale information underlies scientific and technological progress in disciplines ranging from pharmaceutical development to materials synthesis to environmental remediation. While a variety of research tools are used to provide atomic scale information, synchrotron radiation has proved invaluable in this quest. The rapid growth of soft- and hard X-ray synchrotron light sources stands as stark testimony to the importance and utility of synchrotron radiation. Starting from just a handful of synchrotron light sources in the early 1970s, this burgeoning field now includes over 70 proposed, in-construction, or operating facilities in 23 countries on five continents. Along the way, synchrotron light facilities have evolved from small laboratories extracting light parasitically from storage rings designed for high-energy physics research to large, dedicated sources using the latest technology to produce extraordinarily bright photon beams. The basic layout of a multi-GeV storage ring light sourc...

  19. Impedance Source Power Electronic Converters

    DEFF Research Database (Denmark)

    Liu, Yushan; Abu-Rub, Haitham; Ge, Baoming

    Impedance Source Power Electronic Converters brings together state of the art knowledge and cutting edge techniques in various stages of research related to the ever more popular impedance source converters/inverters. Significant research efforts are underway to develop commercially viable...... control methods. Presents the latest power conversion solutions that aim to advance the role of power electronics into industries and sustainable energy conversion systems. Compares impedance source converter/inverter applications in renewable energy power generation and electric vehicles as well...... and technically feasible, efficient and reliable power converters for renewable energy, electric transportation and for various industrial applications. This book provides a detailed understanding of the concepts, designs, controls, and application demonstrations of the impedance source converters/inverters. Key...

  20. The cohesiveness of sourcing teams

    DEFF Research Database (Denmark)

    Lidegaard, Nina

    2015-01-01

    , the practical implementation is often unsuccessful leading to poor performance. Originating in PSM literature, factors influencing sourcing team performance are categorised into three: top management support, organisational structures, and those related to team members. In this paper, the concept...

  1. Mobile Source Observation Database (MSOD)

    Data.gov (United States)

    U.S. Environmental Protection Agency — The Mobile Source Observation Database (MSOD) is a relational database being developed by the Assessment and Standards Division (ASD) of the US Environmental...

  2. Analyzing and Interpreting Historical Sources

    DEFF Research Database (Denmark)

    Kipping, Matthias; Wadhwani, Dan; Bucheli, Marcelo

    2014-01-01

    This chapter outlines a methodology for the interpretation of historical sources, helping to realize their full potential for the study of organization, while overcoming their challenges in terms of distortions created by time, changes in context, and selective production or preservation. Drawing....... The chapter contributes to the creation of a language for describing the use of historical sources in management research.......This chapter outlines a methodology for the interpretation of historical sources, helping to realize their full potential for the study of organization, while overcoming their challenges in terms of distortions created by time, changes in context, and selective production or preservation. Drawing...... on social scientific methods as well as the practice and reflections of historians, the chapter describes analytical and interpretive process based on three basic elements, illustrating them with exemplars from management research: source criticism to identify possible biases and judge the extent to which...

  3. Bayesian Source Separation and Localization

    CERN Document Server

    Knuth, K H

    1998-01-01

    The problem of mixed signals occurs in many different contexts; one of the most familiar being acoustics. The forward problem in acoustics consists of finding the sound pressure levels at various detectors resulting from sound signals emanating from the active acoustic sources. The inverse problem consists of using the sound recorded by the detectors to separate the signals and recover the original source waveforms. In general, the inverse problem is unsolvable without additional information. This general problem is called source separation, and several techniques have been developed that utilize maximum entropy, minimum mutual information, and maximum likelihood. In previous work, it has been demonstrated that these techniques can be recast in a Bayesian framework. This paper demonstrates the power of the Bayesian approach, which provides a natural means for incorporating prior information into a source model. An algorithm is developed that utilizes information regarding both the statistics of the amplitudes...

  4. A-Source Impedance Network

    DEFF Research Database (Denmark)

    Siwakoti, Yam Prasad; Blaabjerg, Frede; Galigekere, Veda Prakash;

    2016-01-01

    A novel A-source impedance network is proposed in this letter. The A-source impedance network uses an autotransformer for realizing converters for any application that demand a very high dc voltage gain. The network utilizes a minimal turns ratio compared to other Magnetically Coupled Impedance S...... with an example single-switch 400 W dc-dc converter. For the closed-loop control design and stability assessment, a small signal model and its analysis of the proposed network are also presented in brief.......A novel A-source impedance network is proposed in this letter. The A-source impedance network uses an autotransformer for realizing converters for any application that demand a very high dc voltage gain. The network utilizes a minimal turns ratio compared to other Magnetically Coupled Impedance...

  5. Automated Classification of ROSAT Sources Using Heterogeneous Multiwavelength Source Catalogs

    Science.gov (United States)

    McGlynn, Thomas; Suchkov, A. A.; Winter, E. L.; Hanisch, R. J.; White, R. L.; Ochsenbein, F.; Derriere, S.; Voges, W.; Corcoran, M. F.

    2004-01-01

    We describe an on-line system for automated classification of X-ray sources, ClassX, and present preliminary results of classification of the three major catalogs of ROSAT sources, RASS BSC, RASS FSC, and WGACAT, into six class categories: stars, white dwarfs, X-ray binaries, galaxies, AGNs, and clusters of galaxies. ClassX is based on a machine learning technology. It represents a system of classifiers, each classifier consisting of a considerable number of oblique decision trees. These trees are built as the classifier is 'trained' to recognize various classes of objects using a training sample of sources of known object types. Each source is characterized by a preselected set of parameters, or attributes; the same set is then used as the classifier conducts classification of sources of unknown identity. The ClassX pipeline features an automatic search for X-ray source counterparts among heterogeneous data sets in on-line data archives using Virtual Observatory protocols; it retrieves from those archives all the attributes required by the selected classifier and inputs them to the classifier. The user input to ClassX is typically a file with target coordinates, optionally complemented with target IDs. The output contains the class name, attributes, and class probabilities for all classified targets. We discuss ways to characterize and assess the classifier quality and performance and present the respective validation procedures. Based on both internal and external validation, we conclude that the ClassX classifiers yield reasonable and reliable classifications for ROSAT sources and have the potential to broaden class representation significantly for rare object types.

  6. Strategic Sourcing in the Army

    Science.gov (United States)

    2013-09-01

    sector:  Total Cost of Ownership tools are applied to understand the life cycle costs of a product or service  Supplier Scorecards to apply a...sourcing efforts, as well as prioritizing new initiatives. In addition to cost and performance goals, any strategic sourcing plan must be balanced with...article/97687/ 39 INITIAL DISTRIBUTION LIST 1. Defense Technical Information Center Ft. Belvoir, Virginia 2. Dudley Knox Library Naval Postgraduate School Monterey, California

  7. Open Source Vulnerability Database Project

    Directory of Open Access Journals (Sweden)

    Jake Kouns

    2008-06-01

    Full Text Available This article introduces the Open Source Vulnerability Database (OSVDB project which manages a global collection of computer security vulnerabilities, available for free use by the information security community. This collection contains information on known security weaknesses in operating systems, software products, protocols, hardware devices, and other infrastructure elements of information technology. The OSVDB project is intended to be the centralized global open source vulnerability collection on the Internet.

  8. Credible sources and sophisticated voters

    DEFF Research Database (Denmark)

    Alt, James E.; Lassen, David D.; Marshall, John

    2016-01-01

    When does new economic information cause voters to reevaluate the government's competence and ultimately vote economically? Since politically relevant information is often conveyed by actors with incentives to influence voter perceptions, the credibility of information sources can vary significan......When does new economic information cause voters to reevaluate the government's competence and ultimately vote economically? Since politically relevant information is often conveyed by actors with incentives to influence voter perceptions, the credibility of information sources can vary...

  9. Asymmetrical Γ-Source Inverters

    DEFF Research Database (Denmark)

    Wei, Mo; Poh Chiang, Loh; Blaabjerg, Frede

    2014-01-01

    , inverters with coupled transformers have been introduced, but they usually lead to high turns ratio, and hence many winding turns, at high gain. An alternative would then be the asymmetrical Γ-source inverters proposed in this paper, whose gain is raised by lowering their turns ratio toward unity. The input...... current drawn by the proposed inverters is smoother and, hence, more adaptable by the source. Theories and experimental results have been presented in this paper for validating the concepts proposed....

  10. LOGISTICS - SOURCE OF COMPETITIVE ADVANTAGE

    OpenAIRE

    Adriana SCRIOSTEANU; Popescu, Daniela

    2014-01-01

    This paper presents the logistics if source of competitive advantage. Logistics can offer a source of competitive advantage, such as a superior position compared to the competitors regarding cost reductions, service diversity and satisfaction of consumer requirements. The logistic activities generate cost and give value to the final product .Despite that the same logistic activity can be done in many ways, with different costs and performance , the evaluation of the activities and the links b...

  11. Cosmic rays from thermal sources

    CERN Document Server

    Wlodarczyk, Z

    2007-01-01

    The energy spectrum of cosmic rays (CR) exhibits very characteristic power-like behavior with the "knee" structure. We consider a generalized statistical model for the production process of cosmic rays which accounts for such behavior in a natural way either by assuming the existence of temperature fluctuations in the source of CR, or by assuming specific temperature distribution of the CR sources. Both possibilities yield the so called Tsallis statistics and lead to the power-like distribution.

  12. The UMLS Knowledge Source server.

    Science.gov (United States)

    McCray, A T; Razi, A

    1995-01-01

    The UMLS Knowledge Source server is an evolving tool for accessing information stored in the UMLS Knowledge Sources. The system architecture is based on the client-server paradigm wherein remote site users send their requests to a centrally managed server at the U.S. National Library of Medicine. The client programs can run on platforms supporting the TCP/IP communication protocol. Access to the system is provided through a command-line interface and through an Application Programming Interface.

  13. rf improvements for Spallation Neutron Source H-ion source

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Yoon W [ORNL; Fuja, Raymond E [ORNL; Goulding, Richard Howell [ORNL; Hardek, Thomas W [ORNL; Lee, Sung-Woo [ORNL; McCarthy, Mike [ORNL; Piller, Chip [ORNL; Shin, Ki [ORNL; Stockli, Martin P [ORNL; Welton, Robert F [ORNL

    2010-01-01

    The Spallation Neutron Source at Oak Ridge National Laboratory is ramping up the accelerated proton beam power to 1.4 MW and just reached 1 MW. The rf-driven multicusp ion source that originates from the Lawrence Berkeley National Laboratory has been delivering 38 mA H beam in the linac at 60 Hz, 0.9 ms. To improve availability, a rf-driven external antenna multicusp ion source with a water-cooled ceramic aluminum nitride AlN plasma chamber is developed. Computer modeling and simulations have been made to analyze and optimize the rf performance of the new ion source. Operational statistics and test runs with up to 56 mA medium energy beam transport beam current identify the 2 MHz rf system as a limiting factor in the system availability and beam production. Plasma ignition system is under development by using a separate 13 MHz system. To improve the availability of the rf power system with easier maintenance, we tested a 70 kV isolation transformer for the 80 kW, 6% duty cycle 2 MHz amplifier to power the ion source from a grounded solid-state amplifier. 2010 American Institute of Physics.

  14. RF Sources for 3rd & 4th Generation Light Sources

    CERN Document Server

    Lenci, Stephan; Bohlen, Heinz Peter; Mizuhara, Albert; Wright, Edward L

    2004-01-01

    The growing number of third and fourth generation light sources has resulted in an increase of the available rf sources to power them. Single beam klystrons are the traditional power source, but the development of IOT’s and multiple-beam klystrons (MBK’s) in L-Band have increased the options for these machines. The Eimac division of CPI has recently built and tested a prototype L-Band IOT, which delivered 30 kW CW at 1.3 GHz. Future work includes the building of an IOT at 1.5 GHz. Meanwhile the MPP division of CPI is currently testing the prototype 10 MW peak, 1.3 GHz MBK for the TESLA x-ray free-electron laser (XFEL). Test results for these new products as well as information on all CPI products at 500 MHz, 1.3 GHz, and 1.5 GHz will be presented.

  15. Ukraine experimental neutron source facility.

    Energy Technology Data Exchange (ETDEWEB)

    Gohar, Y.; Bolshinsky, I.; Nekludov, I.; Karnaukhov, I. (Nuclear Engineering Division); (INL); (Kharkov Institute of Physics and Technology)

    2008-01-01

    Kharkov Institute of Physics and Technology (KIPT) of Ukraine has a plan to construct an experimental neutron source facility. The facility has been developed for producing medical isotopes, training young nuclear professionals, supporting the Ukraine nuclear industry, providing capability for performing reactor physics, material research, and basic science experiments. Argonne National Laboratory (ANL) of USA is collaborating with KIPT on developing this facility. A driven subcritical assembly utilizing the KIPT electron accelerator with a target assembly is used to generate the neutron source. The target assembly utilizes tungsten or uranium for neutron production through photonuclear reactions with 100-KW of electron beam power. The neutron source intensity, spectrum, and spatial distribution have been studied to maximize the neutron yield and satisfy different engineering requirements. The subcritical assembly is designed to obtain the highest possible neutron flux intensity with a subcriticality of 0.98. Low enrichment uranium is used for the fuel material because it enhances the neutron source performance. Safety, reliability, and environmental considerations are included in the facility conceptual design. Horizontal neutron channels are incorporated for performing basic research including cold neutron source. This paper describes the conceptual design and summarizes some of the related analyses.

  16. Compton Sources of Electromagnetic Radiation

    Energy Technology Data Exchange (ETDEWEB)

    Geoffrey Krafft,Gerd Priebe

    2011-01-01

    When a relativistic electron beam interacts with a high-field laser beam, intense and highly collimated electromagnetic radiation will be generated through Compton scattering. Through relativistic upshifting and the relativistic Doppler effect, highly energetic polarized photons are radiated along the electron beam motion when the electrons interact with the laser light. For example, X-ray radiation can be obtained when optical lasers are scattered from electrons of tens-of-MeV beam energy. Because of the desirable properties of the radiation produced, many groups around the world have been designing, building, and utilizing Compton sources for a wide variety of purposes. In this review article, we discuss the generation and properties of the scattered radiation, the types of Compton source devices that have been constructed to date, and the prospects of radiation sources of this general type. Due to the possibilities of producing hard electromagnetic radiation in a device that is small compared to the alternative storage ring sources, it is foreseen that large numbers of such sources may be constructed in the future.

  17. Compact portable electric power sources

    Energy Technology Data Exchange (ETDEWEB)

    Fry, D.N.; Holcomb, D.E.; Munro, J.K.; Oakes, L.C.; Matson, M.J.

    1997-02-01

    This report provides an overview of recent advances in portable electric power source (PEPS) technology and an assessment of emerging PEPS technologies that may meet US Special Operations Command`s (SOCOM) needs in the next 1--2- and 3--5-year time frames. The assessment was performed through a literature search and interviews with experts in various laboratories and companies. Nineteen PEPS technologies were reviewed and characterized as (1) PEPSs that meet SOCOM requirements; (2) PEPSs that could fulfill requirements for special field conditions and locations; (3) potentially high-payoff sources that require additional R and D; and (4) sources unlikely to meet present SOCOM requirements. 6 figs., 10 tabs.

  18. Another Source of Atmospheric Methane

    Institute of Scientific and Technical Information of China (English)

    于心科

    1997-01-01

    The atmospheric concentration of methane is steadily increasin.Lacking of precise estimates of source and sink strengths for the atmospheric methane severely limits the current understanding of the global methane cycle.Agood budget of atmospheric methane can enhance our understanding of the global carbon cycle and global climate change,The known estimates of the main source and sink strengths are gresented in this paper,In terms of carbon isotopic studies,it is evidenced that the earth's primodial methane,which was trapped in the earth during its formation,may be another source of methane,with extensive,earth's degassing which is calleld the "breathing" process of the earth and played an important role in the formation of the promitive atmosphere,large amounts of methane were carried from the deep interior to the surface and then found its way into the atmosphere.

  19. The Herschel Point Source Catalogue

    CERN Document Server

    Marton, Gábor; Altieri, Bruno; Calzoletti, Luca; Kiss, Csaba; Lim, Tanya; Lu, Nanyao; Paladini, Roberta; Papageorgiou, Andreas; Pearson, Chris; Rector, John; Shupe, David; Valtchanov, Ivan; Varga-Verebélyi, Erika; Xu, Kevin

    2015-01-01

    The Herschel Space Observatory was the fourth cornerstone mission in the European Space Agency (ESA) science programme with excellent broad band imaging capabilities in the sub-mm and far-infrared part of the spectrum. Although the spacecraft finished its observations in 2013, it left a large legacy dataset that is far from having been fully scrutinised and still has a large potential for new scientific discoveries. This is specifically true for the photometric observations of the PACS and SPIRE instruments. Some source catalogues have already been produced by individual observing programs, but there are many observations that risk to remain unexplored. To maximise the science return of the SPIRE and PACS data sets, we are in the process of building the Herschel Point Source Catalogue (HPSC) from all primary and parallel mode observations. Our homogeneous source extraction enables a systematic and unbiased comparison of sensitivity across the different Herschel fields that single programs will generally not b...

  20. Materials for spallation neutron sources

    Energy Technology Data Exchange (ETDEWEB)

    Sommer, W.F.; Daemen, L.L. [comps.

    1996-03-01

    The Workshop on Materials for Spallation Neutron Sources at the Los Alamos Neutron Science Center, February 6 to 10, 1995, gathered scientists from Department of Energy national laboratories, other federal institutions, universities, and industry to discuss areas in which work is needed, successful designs and use of materials, and opportunities for further studies. During the first day of the workshop, speakers presented overviews of current spallation neutron sources. During the next 3 days, seven panels allowed speakers to present information on a variety of topics ranging from experimental and theoretical considerations on radiation damage to materials safety issues. An attempt was made to identify specific problems that require attention within the context of spallation neutron sources. This proceedings is a collection of summaries from the overview sessions and the panel presentations.

  1. High average power supercontinuum sources

    Indian Academy of Sciences (India)

    J C Travers

    2010-11-01

    The physical mechanisms and basic experimental techniques for the creation of high average spectral power supercontinuum sources is briefly reviewed. We focus on the use of high-power ytterbium-doped fibre lasers as pump sources, and the use of highly nonlinear photonic crystal fibres as the nonlinear medium. The most common experimental arrangements are described, including both continuous wave fibre laser systems with over 100 W pump power, and picosecond mode-locked, master oscillator power fibre amplifier systems, with over 10 kW peak pump power. These systems can produce broadband supercontinua with over 50 and 1 mW/nm average spectral power, respectively. Techniques for numerical modelling of the supercontinuum sources are presented and used to illustrate some supercontinuum dynamics. Some recent experimental results are presented.

  2. Patients experience of source isolation

    DEFF Research Database (Denmark)

    Johansen, Kamilla; Pedersen, Didde; Kragbak, Nina

    2013-01-01

    Patients´ experience of source isolation - a literature review Title: Patients experience of source isolation – a literature review Authors: Nina Kragbak*, Didde Pedersen*, Kamilla Johansen* and Peter E. Jensen** *students, **lecturer, bachelor in science and Ph.D., at VIA University College......, Nursing education in Århus, Hedeager 2, 8200 Aarhus N, Denmark. Background: Medical treatment and care of patients with infections may include source isolation of the patient, to avoid spreading of the infection. However, isolation is a potential physiological and psychological stress factor...... of the patients perspectives of being isolated to identify areas of potential interest for developing new caring strategies to minimize the negative side effects of isolation. Methods: Literature was systematically searched in CINAHL, Nursing Reference Center, Social Care Online, SveMed+, The Cochrane Library...

  3. Source Segregation and Collection of Source-Segregated Waste

    DEFF Research Database (Denmark)

    Christensen, Thomas Højlund; Matsufuji, Y.

    2011-01-01

    of optimal handling of the waste. But in a few cases, the waste must also be separated at source, for example removing the protective plastic cover from a commercial advertisement received by mail, prior to putting the advertisement into the waste collection bin for recyclable paper. These issues are often...

  4. LIGHT SOURCE: Conceptual design of Hefei advanced light source

    Science.gov (United States)

    Li, Wei-Min; Wang, Lin; Feng, Guang-Yao; Zhang, Shan-Cai; Wu, Cong-Feng; Xu, Hong-Liang; Liu, Zu-Ping

    2009-06-01

    The conceptual of Hefei Advanced Light Source, which is an advanced VUV and Soft X-ray source, was developed at NSRL of USTC. According to the synchrotron radiation user requirements and the trends of SR source development, some accelerator-based schemes were considered and compared; furthermore storage ring with ultra low emittance was adopted as the baseline scheme of HALS. To achieve ultra low emittance, some focusing structures were studied and optimized in the lattice design. Compromising of emittance, on-momentum and off-momentum dynamic aperture and ring scale, five bend acromat (FBA) was employed. In the preliminary design of HALS, the emittance was reduced to sub nm · rad, thus the radiation up to water window has full lateral coherence. The brilliance of undulator radiation covering several eVs to keVs range is higher than that of HLS by several orders. The HALS should be one of the most advanced synchrotron radiation light sources in the world.

  5. Microbial source tracking: a forensic technique for microbial source identification?

    Science.gov (United States)

    Stapleton, Carl M; Wyer, Mark D; Kay, David; Crowther, John; McDonald, Adrian T; Walters, Martin; Gawler, Andrew; Hindle, Terry

    2007-05-01

    As the requirements of the Water Framework Directive (WFD) and the US Clean Water Act (USCWA) for the maintenance of microbiological water quality in 'protected areas' highlight, there is a growing recognition that integrated management of point and diffuse sources of microbial pollution is essential. New information on catchment microbial dynamics and, in particular, the sources of faecal indicator bacteria found in bathing and shellfish harvesting waters is a pre-requisite for the design of any 'programme of measures' at the drainage basin scale to secure and maintain compliance with existing and new health-based microbiological standards. This paper reports on a catchment-scale microbial source tracking (MST) study in the Leven Estuary drainage basin, northwest England, an area for which quantitative faecal indicator source apportionment empirical data and land use information were also collected. Since previous MST studies have been based on laboratory trials using 'manufactured' samples or analyses of spot environmental samples without the contextual microbial flux data (under high and low flow conditions) and source information, such background data are needed to evaluate the utility of MST in USCWA total maximum daily load (TMDL) assessments or WFD 'Programmes of Measures'. Thus, the operational utility of MST remains in some doubt. The results of this investigation, using genotyping of Bacteroidetes using polymerase chain reaction (PCR) and male-specific ribonucleic acid coliphage (F + RNA coliphage) using hybridisation, suggest some discrimination is possible between livestock- and human-derived faecal indicator concentrations but, in inter-grade areas, the degree to which the tracer picture reflected the land use pattern and probable faecal indicator loading were less distinct. Interestingly, the MST data was more reliable on high flow samples when much of the faecal indicator flux from catchment systems occurs. Whilst a useful supplementary tool, the MST

  6. SOURCE PHENOMENOLOGY EXPERIMENTS IN ARIZONA

    Energy Technology Data Exchange (ETDEWEB)

    Jessie L. Bonner; Brian Stump; Mark Leidig; Heather Hooper; Xiaoning (David) Yang; Rongmao Zhou; Tae Sung Kim; William R. Walter; Aaron Velasco; Chris Hayward; Diane Baker; C. L. Edwards; Steven Harder; Travis Glenn; Cleat Zeiler; James Britton; James F. Lewkowicz

    2005-09-30

    The Arizona Source Phenomenology Experiments (SPE) have resulted in an important dataset for the nuclear monitoring community. The 19 dedicated single-fired explosions and multiple delay-fired mining explosions were recorded by one of the most densely instrumented accelerometer and seismometer arrays ever fielded, and the data have already proven useful in quantifying confinement and excitation effects for the sources. It is very interesting to note that we have observed differences in the phenomenology of these two series of explosions resulting from the differences between the relatively slow (limestone) and fast (granodiorite) media. We observed differences at the two SPE sites in the way the rock failed during the explosions, how the S-waves were generated, and the amplitude behavior as a function of confinement. Our consortium's goal is to use the synergy of the multiple datasets collected during this experiment to unravel the phenomenological differences between the two emplacement media. The data suggest that the main difference between single-fired chemical and delay-fired mining explosion seismograms at regional distances is the increased surface wave energy for the latter source type. The effect of the delay-firing is to decrease the high-frequency P-wave amplitudes while increasing the surface wave energy because of the longer source duration and spall components. The results suggest that the single-fired explosions are surrogates for nuclear explosions in higher frequency bands (e.g., 6-8 Hz Pg/Lg discriminants). We have shown that the SPE shots, together with the mining explosions, are efficient sources of S-wave energy, and our next research stage is to postulate the possible sources contributing to the shear-wave energy.

  7. Gas and metal ion sources

    Energy Technology Data Exchange (ETDEWEB)

    Oaks, E. [High Current Electronics Institute, Tomsk (Russian Federation)]|[State Academy of Control System and Radioelectronics, Tomsk (Russian Federation); Yushkov, G. [High Current Electronics Institute, Tomsk (Russian Federation)

    1996-08-01

    The positive ion sources are now of interest owing to both their conventional use, e.g., as injectors in charged-particle accelerators and the promising capabilities of intense ion beams in the processes related to the action of ions on various solid surfaces. For industrial use, the sources of intense ion beams and their power supplies should meet the specific requirements as follows: They should be simple, technologically effective, reliable, and relatively low-cost. Since the scanning of an intense ion beam is a complicated problem, broad ion beams hold the greatest promise. For the best use of such beams it is desirable that the ion current density be uniformly distributed over the beam cross section. The ion beam current density should be high enough for the treatment process be accomplished for an acceptable time. Thus, the ion sources used for high-current, high-dose metallurgical implantation should provide for gaining an exposure dose of {approximately} 10{sup 17} cm{sup {minus}2} in some tens of minutes. So the average ion current density at the surface under treatment should be over 10{sup {minus}5} A/cm{sup 2}. The upper limit of the current density depends on the admissible heating of the surface under treatment. The accelerating voltage of an ion source is dictated by its specific use; it seems to lie in the range from {approximately}1 kV (for the ion source used for surface sputtering) to {approximately}100 kV and over (for the ion sources used for high-current, high-dose metallurgical implantation).

  8. The Herschel Point Source Catalogue

    Science.gov (United States)

    Marton, Gabor; Schulz, Bernhard; Altieri, Bruno; Calzoletti, Luca; Kiss, Csaba; Lim, Tanya; Lu, Nanyao; Paladini, Roberta; Papageorgiou, Andreas; Pearson, Chris; Rector, John; Shupe, David; Valtchanov, Ivan; Verebélyi, Erika; Xu, Kevin

    2015-08-01

    The Herschel Space Observatory was the fourth cornerstone mission in the European Space Agency (ESA) science programme with excellent broad band imaging capabilities in the submillimetre and far-infrared part of the spectrum. Although the spacecraft finished its observations in 2013, it left a large legacy dataset that is far from having been fully scrutinized and still has potential for new scientific discoveries. This is specifically true for the photometric observations of the PACS and SPIRE instruments that scanned >10% of the sky at 70, 100, 160, 250, 350 and 500 microns. Some source catalogs have already been produced by individual observing programs, but there are many observations that would never be analyzed for their full source content. To maximize the science return of the SPIRE and PACS data sets, our international team of instrument experts is in the process of building the Herschel Point Source Catalog (HPSC) from all scan map observations. Our homogeneous source extraction enables a systematic and unbiased comparison of sensitivity across the different Herschel fields that single programs will generally not be able to provide. The extracted point sources will contain individual YSOs of our Galaxy, unresolved YSO clusters in resolved nearby galaxies and unresolved galaxies of the local and distant Universe that are related to star formation. Such a huge dataset will help scientists better understand the evolution from interstellar clouds to individual stars. Furthermore the analysis of stellar clusters and the star formation on galactic scales will add more details to the understanding of star formation laws through time.We present our findings on comparison of different source detection and photometric tools. First results of the extractions are shown along with the description of our pipelines and catalogue entries. We also provide an additional science product, the structure noise map, that is used for the quality assessment of the catalogue in

  9. Embedded EZ-Source Inverters

    DEFF Research Database (Denmark)

    Blaabjerg, Frede; Loh, Poh Chiang; Gao, F.

    2008-01-01

    -voltage oscillations to the system. Therefore, Z-source inverters are in effect safer and less complex, and can be implemented using only passive elements with no additional active semiconductor needed. Believing in the prospects of Z-source inverters, this paper contributes by introducing a new family of embedded EZ...... since an added filter will raise the system cost, and at times can complicate the dynamic tuning and resonant consideration of the inverters. The same embedded concept can also be used for designing a full range of voltage and current-type inverters with each of them tested experimentally using a number...

  10. Penetration Tester's Open Source Toolkit

    CERN Document Server

    Faircloth, Jeremy

    2011-01-01

    Great commercial penetration testing tools can be very expensive and sometimes hard to use or of questionable accuracy. This book helps solve both of these problems. The open source, no-cost penetration testing tools presented do a great job and can be modified by the user for each situation. Many tools, even ones that cost thousands of dollars, do not come with any type of instruction on how and in which situations the penetration tester can best use them. Penetration Tester's Open Source Toolkit, Third Edition, expands upon existing instructions so that a professional can get the most accura

  11. Sourcing teams and interdepartmental integration

    DEFF Research Database (Denmark)

    Lidegaard, Nina; Ellegaard, Chris; Møller, Morten Munksgaard

    2015-01-01

    Internal integration is often mentioned as a prerequisite for conducting strategic sourcing, as multiple functional departments must collaborate on creating value-creating activities amongst them. Though it is one of many possibilities, the use of cross-functional teams is often the most commonly...... proposed solution to ensure internal integration. This paper presents an exploratory case study evaluating the use of internal integration mechanisms in a cross-functional sourcing process. Two commodity categories are examined. One is organised in a cross-functional team, while the other is not. Findings...

  12. Sources of information and assistance

    Energy Technology Data Exchange (ETDEWEB)

    Tickton, S.G.

    1981-01-01

    The best sources of information on energy activities, including conservation and education, are the officials of the state and federal energy departments and offices, the editors of the trade and professional journals in the various branches of the energy field, and the directors of the organizations working on energy issues. A selected list of information sources includes the title and address rather than individual names in order to remain current. The directory begins with state energy offices, followed by DOE and other officials, and an alphabetical listing of schools, organizations, and institutions. The directory is the final chapter of New Approaches to Energy Conservation, a sourcebook published by New Directions for Higher Education.

  13. Distributed source coding of video

    DEFF Research Database (Denmark)

    Forchhammer, Søren; Van Luong, Huynh

    2015-01-01

    A foundation for distributed source coding was established in the classic papers of Slepian-Wolf (SW) [1] and Wyner-Ziv (WZ) [2]. This has provided a starting point for work on Distributed Video Coding (DVC), which exploits the source statistics at the decoder side offering shifting processing...... steps, conventionally performed at the video encoder side, to the decoder side. Emerging applications such as wireless visual sensor networks and wireless video surveillance all require lightweight video encoding with high coding efficiency and error-resilience. The video data of DVC schemes differ from...

  14. Modulation of Current Source Inverter

    Directory of Open Access Journals (Sweden)

    Golam Reza Arab Markadeh

    2011-04-01

    Full Text Available Direct torque control with Current Source Inverter (CSI instead of voltage source inverter is so appropriate because of determining the torque of induction motor with machine current and air gap flux. In addition, Space-Vector Modulation (SVM is a more proper method for CSI because of low order harmonics reduction, lower switching frequency and easier implementation. This paper introduces the SVM method for CSI and uses the proposed inverter for vector control of an induction motor. The simulation results illustrate fast dynamic response and desirable torque and speed output. Fast and accurate response to changes of speed and load torque reference completely proves the prominence of this method.

  15. Development of Radioisotope Micropower Sources

    Science.gov (United States)

    Robertson, J. David

    2016-09-01

    Microelectromechanical systems (MEMS) are considered to be one of the discriminating technologies of the 21st century. In order to take full advantage of the MEMS revolution, the power sources for these electromechanical systems must follow a similar trend of increased functionality at decreased size. Because of their high energy density, radioactive micropower sources are an alternative to next generation battery and fuel cell technologies for applications where volume is at a premium. This presentation will focus on our development of liquid-semiconductor nuclear batteries as compact power supplies for MEMS.

  16. Online bibliographic sources in hydrology

    Science.gov (United States)

    Wild, Emily C.; Havener, W. Michael

    2001-01-01

    Traditional commercial bibliographic databases and indexes provide some access to hydrology materials produced by the government; however, these sources do not provide comprehensive coverage of relevant hydrologic publications. This paper discusses bibliographic information available from the federal government and state geological surveys, water resources agencies, and depositories. In addition to information in these databases, the paper describes the scope, styles of citing, subject terminology, and the ways these information sources are currently being searched, formally and informally, by hydrologists. Information available from the federal and state agencies and from the state depositories might be missed by limiting searches to commercially distributed databases.

  17. Consumer Trust in Information Sources

    Directory of Open Access Journals (Sweden)

    Brad Love

    2013-06-01

    Full Text Available Trust is essential to understanding public reaction to innovative issues. This research focuses on trust in information sources by explicating the construct of trust and testing a comprehensive model on several information sources about genetically modified foods. Results from a survey of 369 participants reveal the significance of projecting competence and the role of the environment in which a target public receives information. Perceptions of regulatory, social, business, and technical environments affect how likely individuals are to follow advice from institutions like the Food and Drug Administration and the news media. Future research should incorporate knowledge levels and personal relevance as variables likely to influence trusting relationships.

  18. Open source systems security certification

    CERN Document Server

    Damiani, Ernesto; El Ioini, Nabil

    2009-01-01

    Open Source Advances in Computer Applications book series provides timely technological and business information for: Enabling Open Source Systems (OSS) to become an integral part of systems and devices produced by technology companies; Inserting OSS in the critical path of complex network development and embedded products, including methodologies and tools for domain-specific OSS testing (lab code available), plus certification of security, dependability and safety properties for complex systems; Ensuring integrated systems, including OSS, meet performance and security requirements as well as achieving the necessary certifications, according to the overall strategy of OSS usage on the part of the adopter

  19. Land Streamer Surveying Using Multiple Sources

    KAUST Repository

    Mahmoud, Sherif

    2014-12-11

    Various examples are provided for land streamer seismic surveying using multiple sources. In one example, among others, a method includes disposing a land streamer in-line with first and second shot sources. The first shot source is at a first source location adjacent to a proximal end of the land streamer and the second shot source is at a second source location separated by a fixed length corresponding to a length of the land streamer. Shot gathers can be obtained when the shot sources are fired. In another example, a system includes a land streamer including a plurality of receivers, a first shot source located adjacent to the proximal end of the land streamer, and a second shot source located in-line with the land streamer and the first shot source. The second shot source is separated from the first shot source by a fixed overall length corresponding to the land streamer.

  20. Source Reference File Usage: Management Summary

    Data.gov (United States)

    Social Security Administration — A report by region then by state that details how often medical sources from the Source Reference File are used when taking disability claims vs. sources that are...

  1. EPA Region 1 Sole Source Aquifers

    Data.gov (United States)

    U.S. Environmental Protection Agency — This coverage contains boundaries of EPA-approved sole source aquifers. Sole source aquifers are defined as an aquifer designated as the sole or principal source of...

  2. History Sources on the Internet.

    Science.gov (United States)

    Fink, Kenneth D.

    This paper provides descriptions of key online history resources useful to teachers, librarians, and other education professionals. Highlights include: primary sources on the Internet; archives; Online Public Access Catalogs (OPACs); the American Historical Association (AHA) Web site; state and federal government resources; business history…

  3. Synthetic aperture controlled source electromagnetics

    NARCIS (Netherlands)

    Fan, Y.; Snieder, R.; Slob, E.; Hunziker, J.W.; Singer, J.; Sheiman, J.; Rosenquist, M.

    2010-01-01

    Controlled‐source electromagnetics (CSEM) has been used as a de‐risking tool in the hydrocarbon exploration industry. Although there have been successful applications of CSEM, this technique is still not widely used in the industry because the limited types of hydrocarbon reservoirs CSEM can detect.

  4. Guide to Sources: Advertising. Revised.

    Science.gov (United States)

    White, Lucinda M.

    This guide is designed to introduce the student to some of the major sources of advertising information available in the Fogler Library at the University of Maine. A brief description and exploration of the card catalog, Library of Congress Subject Headings, Library of Congress Classification System, and the Dewey Decimal System are included. In…

  5. [Dreams in ancient Hebrew sources].

    Science.gov (United States)

    Kottek, Samuel S

    2009-01-01

    As in many cultures dreams are, in Hebrew sources, the object of numerous questions where are dreams from? Which is their function? Are they a physical or metaphysical phenomenon? The article analyzes the topic of nature of dreams in the Bible, with a particolar attention devoted to the Joseph's history. Talmudic text are, in particular, rich in references.

  6. Energy Sources: An Historical Perspective.

    Science.gov (United States)

    Perry, Constance M.

    1983-01-01

    Putting the present energy situation into an historical perspective provides meaning to today's energy concerns and demonstrates how important energy has always been to our life style. Primary energy sources of the United States from 1850 to the present are examined. (RM)

  7. Open Source Wifi Hotspot Implementation

    Directory of Open Access Journals (Sweden)

    Tyler Sondag

    2007-06-01

    Full Text Available The goal of this paper is to describe a design—including the hardware, software, and configuration––for an open source wireless network. The network designed will require authentication. While care will be taken to keep the authentication exchange secure, the network will otherwise transmit data without encryption.

  8. Organizing for External Knowledge Sourcing

    DEFF Research Database (Denmark)

    Rabbiosi, Larissa; Reichstein, Toke

    2011-01-01

    The aim of this article is to provide an introduction to the special issue. We briefly consider the external knowledge sourcing and organizing for innovation literatures, which offer a background for the special issue, and we highlight their mutual dialogue. We then illustrate the main findings...

  9. Govt. Pubs.: NTIS Reference Sources.

    Science.gov (United States)

    Korman, Richard; Aluri, Rao

    1980-01-01

    Cites review sources for NTIS (National Technical Information Service) publications and provides an annotated list of 22 reports on child abuse, Chinese language romanization, criminal justice, energy, environment, ethnic data, fire technology, genealogy, health care, local communities and federal assistance, mainstreaming, political leadership in…

  10. Guam and Micronesia Reference Sources.

    Science.gov (United States)

    Goetzfridt, Nicholas J.; Goniwiecha, Mark C.

    1993-01-01

    This article lists reference sources for studying Guam and Micronesia. The entries are arranged alphabetically by main entry within each section in the categories of: (1) bibliographical works; (2) travel and guide books; (3) handbooks and surveys; (4) dictionaries; (5) yearbooks; (6) periodical and newspaper publications; and (7) audiovisual…

  11. Synchrotron-driven spallation sources

    CERN Document Server

    Bryant, P J

    1996-01-01

    The use of synchrotrons for pulsed neutron spallation sources is an example of scientific and technological spin-off from the accelerator development for particle physics. Accelerator-driven sources provide an alternative to the continuous-flux, nuclear reactors that currently furnish the majority of neutrons for research and development. Although the present demand for neutrons can be adequately met by the existing reactors, this situation is unlikely to continue due to the increasing severity of safety regulations and the declared policies of many countries to close down their reactors within the next decade or so. Since the demand for neutrons as a research tool is, in any case,expected to grow, there has been a corresponding interest in sources that are synchrotron-driven or linac-driven with a pulse compression ring and currently several design studies are being made. These accelerator-driven sources also have the advantage of a time structure with a high peak neutron flux. The basic requirement is for a...

  12. The Source for Asperger's Syndrome.

    Science.gov (United States)

    Kowalski, Timothy P.

    This book is intended as a comprehensive source of information on the diagnosis and treatment of Asperger syndrome. Chapter 1 discusses major classification of characteristics and chapter 2 describes prevalence, comorbidity, and causal factors of Asperger syndrome. Chapter 3 examines clinical diagnosis and misdiagnosis and the influence of…

  13. On Source of Mary's Tragedy

    Institute of Scientific and Technical Information of China (English)

    胡杰

    2016-01-01

    Long Day's Journey into Night is a great work of American dramatist Eugene O'Neill. As the only female protagonist fully portrayed in the play, Mary's tragedy generated a hot debate. In this thesis, through detailed analysis, it is found that Mary is the victim of male-dominated society and men are the source of her tragedy.

  14. Leveraging Synergiesn in Global Sourcing

    DEFF Research Database (Denmark)

    Englyst, Linda; Stegmann Mikkelsen, Ole; Johansen, John

    2005-01-01

    Leveraging synergies in global sourcing is not a straightforward task, and requires a balanced approach to organizing, taking into consideration a number of situational factors. These include, but are not limited to, strategic significance, product specificity, market complexity, coherency and th...

  15. Primary Sources Enliven Civil War

    Science.gov (United States)

    Robelen, Erik W.

    2011-01-01

    Today, a growing number of teachers are moving beyond the textbook in teaching about the war, and U.S. history more broadly. Teachers are digging directly into primary sources and harnessing technology, all in an attempt to help students better understand the past and bring it to life. Doing so may be especially important with the Civil War,…

  16. Primary Sources and Inquiry Learning

    Science.gov (United States)

    Pappas, Marjorie L.

    2006-01-01

    In this article, the author discusses inquiry learning and primary sources. Inquiry learning puts students in the active role of investigators. Questioning, authentic and active learning, and interactivity are a few of the characteristics of inquiry learning that put the teacher and library media specialist in the role of coaches while students…

  17. Compact Photon Source Conceptual Design

    Energy Technology Data Exchange (ETDEWEB)

    Degtyarenko, Pavel V. [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Wojtsekhowski, Bogdan B. [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States)

    2016-04-01

    We describe options for the production of an intense photon beam at the CEBAF Hall D Tagger facility, needed for creating a high-quality secondary K 0 L delivered to the Hall D detector. The conceptual design for the Compact Photon Source apparatus is presented.

  18. Alternative sources of natural rubber

    NARCIS (Netherlands)

    Mooibroek, H.; Cornish, K.

    2000-01-01

    Rubber (cis-1,4-polyisoprene) is one of the most important polymers naturally produced by plants because it is a strategic raw material used in more than 40,000 products, including more than 400 medical devices. The sole commercial source, at present, is natural rubber harvested from the Brazilian r

  19. FORTRAN Static Source Code Analyzer

    Science.gov (United States)

    Merwarth, P.

    1984-01-01

    FORTRAN Static Source Code Analyzer program, SAP (DEC VAX version), automatically gathers statistics on occurrences of statements and structures within FORTRAN program and provides reports of those statistics. Provisions made for weighting each statistic and provide an overall figure of complexity.

  20. Six Regularities of Source Recognition

    Science.gov (United States)

    Glanzer, Murray; Hilford, Andy; Kim, Kisok

    2004-01-01

    In recent work, researchers have shown that source-recognition memory can be incorporated in an extended signal detection model that covers both it and item-recognition memory (A. Hilford, M. Glanzer, K. Kim, & L. T. DeCarlo, 2002). In 5 experiments, using learning variables that have an established effect on item recognition, the authors tested…

  1. Miniaturized cathodic arc plasma source

    Science.gov (United States)

    Anders, Andre; MacGill, Robert A.

    2003-04-15

    A cathodic arc plasma source has an anode formed of a plurality of spaced baffles which extend beyond the active cathode surface of the cathode. With the open baffle structure of the anode, most macroparticles pass through the gaps between the baffles and reflect off the baffles out of the plasma stream that enters a filter. Thus the anode not only has an electrical function but serves as a prefilter. The cathode has a small diameter, e.g. a rod of about 1/4 inch (6.25 mm) diameter. Thus the plasma source output is well localized, even with cathode spot movement which is limited in area, so that it effectively couples into a miniaturized filter. With a small area cathode, the material eroded from the cathode needs to be replaced to maintain plasma production. Therefore, the source includes a cathode advancement or feed mechanism coupled to cathode rod. The cathode also requires a cooling mechanism. The movable cathode rod is housed in a cooled metal shield or tube which serves as both a current conductor, thus reducing ohmic heat produced in the cathode, and as the heat sink for heat generated at or near the cathode. Cooling of the cathode housing tube is done by contact with coolant at a place remote from the active cathode surface. The source is operated in pulsed mode at relatively high currents, about 1 kA. The high arc current can also be used to operate the magnetic filter. A cathodic arc plasma deposition system using this source can be used for the deposition of ultrathin amorphous hard carbon (a-C) films for the magnetic storage industry.

  2. Distributed Joint Source-Channel Coding for arbitrary memoryless correlated sources and Source coding for Markov correlated sources using LDPC codes

    CERN Document Server

    Aggarwal, Vaneet

    2008-01-01

    In this paper, we give a distributed joint source channel coding scheme for arbitrary correlated sources for arbitrary point in the Slepian-Wolf rate region, and arbitrary link capacities using LDPC codes. We consider the Slepian-Wolf setting of two sources and one destination, with one of the sources derived from the other source by some correlation model known at the decoder. Distributed encoding and separate decoding is used for the two sources. We also give a distributed source coding scheme when the source correlation has memory to achieve any point in the Slepian-Wolf rate achievable region. In this setting, we perform separate encoding but joint decoding.

  3. Effect of Electron Seeding on Experimentally Measured Multipactor Discharge Threshold

    Science.gov (United States)

    Noland, Jonathan; Graves, Timothy; Lemon, Colby; Looper, Mark; Farkas, Alex

    2012-10-01

    Multipactor is a vacuum phenomenon in which electrons, moving in resonance with an externally applied electric field, impact material surfaces. If the number of secondary electrons created per primary electron impact averages more than unity, the resonant interaction can lead to an electron avalanche. Multipactor is a generally undesirable phenomenon, as it can cause local heating, absorb power, or cause detuning of RF circuits. In order to increase the probability of multipactor initiation, test facilities often employ various seeding sources such as radioactive sources (Cesium 137, Strontium 90), electron guns, or photon sources. Even with these sources, the voltage for multipactor initiation is not certain as parameters such as material type, RF pulse length, and device wall thickness can all affect seed electron flux and energy in critical gap regions, and hence the measured voltage threshold. This study investigates the effects of seed electron source type (e.g., photons versus beta particles), material type, gap size, and RF pulse length variation on multipactor threshold. In addition to the experimental work, GEANT4 simulations will be used to estimate the production rate of low energy electrons (< 5 keV) by high energy electrons and photons. A comparison of the experimental fluxes to the typical energetic photon and particle fluxes experienced by spacecraft in various orbits will also be made. Initial results indicate that for a simple, parallel plate device made of aluminum, there is no threshold variation (with seed electrons versus with no seed electrons) under continuous-wave RF exposure.

  4. TSUNAMI INFORMATION SOURCES - PART 4

    Directory of Open Access Journals (Sweden)

    Robert L. Wiegel

    2006-01-01

    Full Text Available I have expanded substantially my list of information sources on: tsunami generation (sources, impulsive mechanisms, propagation, effects of nearshore bathymetry, and wave run-up on shore - including physical (hydraulic modeling and numerical modeling. This expanded list includes the subjects of field investigations of tsunamis soon after an event; damage effects in harbors on boats, ships, and facilities; tsunami wave-induced forces; damage by tsunami waves to structures on shore; scour/erosion; hazard mitigation; land use planning; zoning; siting, design, construction and maintenance of structures and infrastructure; public awareness and education; distant and local sources; tsunami warning and evacuation programs; tsunami probability and risk criteria. A few references are on "sedimentary signatures" useful in the study of historic and prehistoric tsunamis (paleo-tsunamis. In addition to references specifically on tsunamis, there are references on long water wave and solitary wave theory; wave refraction, diffraction, and reflection; shelf and basin free and forced oscillations (bay and harbor response; seiches; edge waves; Mach- reflection of long water waves ("stem waves"; wave run-up on shore; energy dissipation. All are important in understanding tsunamis, and in hazard mitigation. References are given on subaerial and submarine landslide (and rockfall generated waves in reservoirs, fjords, bays, and ocean; volcano explosive eruptions/collapse; underwater and surface explosions; asteroid impact. This report is in two parts: 1 Bibliographies, books and pamphlets, catalogs, collections, journals and newsletters, maps, organizations, proceedings, videos and photos; 2 Articles, papers, reports listed alphabetically by author.Many papers on the Indian Ocean (Sumatra tsunami of 26 December 2004, were given at the 22nd IUGG International Tsunami Symposium, Chania, Crete, 27-29 June 2005, but had not been published at the date of this report. For

  5. The ILC polarized electron source

    CERN Document Server

    Brachmann, Axel; Garwin, Edward; Kirby, Robert; Luh Dah An; Maruyama, Takashi; Prepost, Richard; Schultz, David; Sheppard, John

    2005-01-01

    The SLC polarized electron source (PES) can meet the expected requirements of the International Linear Collider (ILC) for polarization, charge and lifetime. However, experience with newer and successful PES designs at JLAB, Mainz and elsewhere can be incorporated into a first-generation ILC source that will emphasize reliability and stability without compromising the photocathode performance. The long pulse train for the ILC may introduce new challenges for the PES, and in addition more reliable and stable operation of the PES may be achievable if appropriate R&D is carried out for higher voltage operation and for a simpler load-lock system. The outline of the R&D program currently taking shape at SLAC and elsewhere is discussed. The principal components of the proposed ILC PES, including the laser system necessary for operational tests, are described.

  6. Distributed source coding of video

    DEFF Research Database (Denmark)

    Forchhammer, Søren; Van Luong, Huynh

    2015-01-01

    steps, conventionally performed at the video encoder side, to the decoder side. Emerging applications such as wireless visual sensor networks and wireless video surveillance all require lightweight video encoding with high coding efficiency and error-resilience. The video data of DVC schemes differ from......A foundation for distributed source coding was established in the classic papers of Slepian-Wolf (SW) [1] and Wyner-Ziv (WZ) [2]. This has provided a starting point for work on Distributed Video Coding (DVC), which exploits the source statistics at the decoder side offering shifting processing...... the assumptions of SW and WZ distributed coding, e.g. by being correlated in time and nonstationary. Improving the efficiency of DVC coding is challenging. This paper presents some selected techniques to address the DVC challenges. Focus is put on pin-pointing how the decoder steps are modified to provide...

  7. Rapidly pulsed helium droplet source

    Energy Technology Data Exchange (ETDEWEB)

    Pentlehner, Dominik; Riechers, Ricarda; Dick, Bernhard; Slenczka, Alkwin [Institute for Physical and Theoretical Chemistry, University of Regensburg, 93053 Regensburg (Germany); Even, Uzi; Lavie, Nachum; Brown, Raviv; Luria, Kfir [Sackler Faculty of Exact Sciences, School of Chemistry, Tel Aviv University, Ramat Aviv, 69978 Tel Aviv (Israel)

    2009-04-15

    A pulsed valve connected to a closed-cycle cryostat was optimized for producing helium droplets. The pulsed droplet beam appeared with a bimodal size distribution. The leading part of the pulse consists of droplets suitable for doping with molecules. The average size of this part can be varied between 10{sup 4} and 10{sup 6} helium atoms, and the width of the distribution is smaller as compared to a continuous-flow droplet source. The system has been tested in a single pulse mode and at repetition rates of up to 500 Hz with almost constant intensity. The droplet density was found to be increased by more than an order of magnitude as compared to a continuous-flow droplet source.

  8. PERSPECTIVE: Dust, fertilization and sources

    Science.gov (United States)

    Remer, Lorraine A.

    2006-11-01

    fraction that arrives at another continent [2]. At the deposition end of the chain, it is still unclear how the limited minerals in the dust such as iron are released for uptake by organisms either on land or in the ocean. Not all dust deposited into oceans results in a phytoplankton bloom. The process requires a chemical pathway that mobilizes a fraction of the iron into soluble form. Meskhidze et al [3] show that phytoplankton blooms following dust transport from the Gobi desert in Asia into the Pacific ocean result in a phytoplankton bloom only if the dust is accompanied by high initial SO2-to-dust ratios, suggesting that sulfuric acid coatings on the dust particle mobilize the embedded iron in the dust for phytoplankton uptake. Quantifying transport, deposition and nutrient availability are the latter ends of a puzzle that must begin by identifying and quantifying dust emission at the sources. The emission process is complex at the microscale requiring the right conditions for saltation and bombardment, which makes identification and inclusion of sources in global transport models very difficult. The result is that estimates of annual global dust emissions range from 1000 to 3000 Tg per year [4]. Even as global estimates of dust emissions are uncertain, localizing the sources brings even greater uncertainty. It has been recognized for several years that dust sources are not uniformly distributed over the arid regions of the Earth, but are regulated to topographic lows associated with dried lake deposits [5]. Using aerosol information from satellites, a comprehensive map of the world's source regions shows sources localized to specific areas of the Earth's arid regions [6]. Still these maps suggest broad emission sources covering several degrees of latitude and longitude. In the paper by Koren and co-authors [7] appearing in this issue, one particular dust source, the Bodélé depression in Chad, is analyzed in detail. They find that the specific topography of the

  9. Gravitational radiation sources and signatures

    CERN Document Server

    Finn, L S

    2001-01-01

    The goal of these lecture notes is to introduce the developing research area of gravitational-wave phenomenology. In more concrete terms, they are meant to provide an overview of gravitational-wave sources and an introduction to the interpretation of real gravitational wave detector data. They are, of course, limited in both regards. Either topic could be the subject of one or more books, and certainly more than the few lectures possible in a summer school. Nevertheless, it is possible to talk about the problems of data analysis and give something of their flavor, and do the same for gravitational wave sources that might be observed in the upcoming generation of sensitive detectors. These notes are an attempt to do just that.

  10. Escaping "localisms" in IT sourcing

    DEFF Research Database (Denmark)

    Mola, L.; Carugati, Andrea

    2012-01-01

    Organizations are limited in their choices by the institutional environment in which they operate. This is particularly true for IT sourcing decisions that go beyond cost considerations and are constrained by traditions, geographical location, and social networks. This article investigates how...... a company can disentangle itself from the constraints of the institutional environment. We do so drawing on a longitudinal case study of an Italian SME active in the steel industry that successfully changed its institutionally sound, but increasingly inefficient, IT sourcing practice. Our main result...... suggests that by attending steadily to institutional logics, organizations can become selective in how the institutional environment influences them and act more purposefully in their decisions. In particular, through the creation of companywide IT management competencies and targeted hiring practices...

  11. Resonance Ionization Laser Ion Sources

    CERN Document Server

    Marsh, B

    2013-01-01

    The application of the technique of laser resonance ionization to the production of singly charged ions at radioactive ion beam facilities is discussed. The ability to combine high efficiency and element selectivity makes a resonance ionization laser ion source (RILIS) an important component of many radioactive ion beam facilities. At CERN, for example, the RILIS is the most commonly used ion source of the ISOLDE facility, with a yearly operating time of up to 3000 hours. For some isotopes the RILIS can also be used as a fast and sensitive laser spectroscopy tool, provided that the spectral resolution is sufficiently high to reveal the influence of nuclear structure on the atomic spectra. This enables the study of nuclear properties of isotopes with production rates even lower than one ion per second and, in some cases, enables isomer selective ionization. The solutions available for the implementation of resonance laser ionization at radioactive ion beam facilities are summarized. Aspects such as the laser r...

  12. Data Sources for Human Behavior

    Science.gov (United States)

    2009-08-06

    Std Z39-18 Academic primary sources • Have search done by professional • Search Discipline Databases Social Sciences Citation Index – – Psycinfo...DRIVEN. WARFIGHTER FOCUSED. Databases UNCLASSIFIED – Approved for Public Release SOCIAL SCIENCES CITATION INDEX Home Science Products & Services Products...A - Z Social Sciences Citation Index PRODUCT S & SERV ICES • Products A -Z Life Sciences Scholarly Research , Publishing and Analysis

  13. Operation of ECR Ion Source

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    In 2001, ECR ion source was operated for HIRFL about 5138 hours and 8 species of ion beams, such as ~(12)C~(4+), ~(12)C~(5+), ~(36)Ar~(11+),~(13)C~(4+),~(40)Ca~(11+),~(40)Ar~(11+),~(56)Fe~(10+) and ~(18)O~(6+) were provided. Among these ions,~(56)Fe~(10+)is a new ion beam. In this period, 14 experiments of heavy ion physics application and nuclear research were finished.

  14. Tracing the source of campylobacteriosis.

    Directory of Open Access Journals (Sweden)

    Daniel J Wilson

    Full Text Available Campylobacter jejuni is the leading cause of bacterial gastro-enteritis in the developed world. It is thought to infect 2-3 million people a year in the US alone, at a cost to the economy in excess of US $4 billion. C. jejuni is a widespread zoonotic pathogen that is carried by animals farmed for meat and poultry. A connection with contaminated food is recognized, but C. jejuni is also commonly found in wild animals and water sources. Phylogenetic studies have suggested that genotypes pathogenic to humans bear greatest resemblance to non-livestock isolates. Moreover, seasonal variation in campylobacteriosis bears the hallmarks of water-borne disease, and certain outbreaks have been attributed to contamination of drinking water. As a result, the relative importance of these reservoirs to human disease is controversial. We use multilocus sequence typing to genotype 1,231 cases of C. jejuni isolated from patients in Lancashire, England. By modeling the DNA sequence evolution and zoonotic transmission of C. jejuni between host species and the environment, we assign human cases probabilistically to source populations. Our novel population genetics approach reveals that the vast majority (97% of sporadic disease can be attributed to animals farmed for meat and poultry. Chicken and cattle are the principal sources of C. jejuni pathogenic to humans, whereas wild animal and environmental sources are responsible for just 3% of disease. Our results imply that the primary transmission route is through the food chain, and suggest that incidence could be dramatically reduced by enhanced on-farm biosecurity or preventing food-borne transmission.

  15. The sources of natural antioxidants

    Directory of Open Access Journals (Sweden)

    Elżbieta Sikora

    2008-03-01

    Full Text Available Intensive oxidative processes occuring in human organism lead to formation of oxygen reactive forms, which can damage systemic cells and tissues. It is shown, that body endogenous protective system can be supported in that case by natural antioxidant compounds provided from food. The assessment of food products as the potential sources of antioxidants was performed, taking into consideration the kinds of compounds supplied, and their significance in the diet of different nations.

  16. Thermal Radiation Source Test Facility,

    Science.gov (United States)

    1984-01-01

    KEY WORDS (Continu on revers side I eesr and identify by block nuMb.,) Thermal Radiation Source Thermal Test Facility 20 ABSTRACT (Continue on reverse...SECTION 1 INTRODUCTION 1-1 GENERAL Defense Nuclear Agency’s Field Command, located at Kirtland AFB in New Mexico, has recently upgraded its thermal test facility...is used to evaluate damage and survivability in a nuclear environment. The thermal test facility was first established in 1979 and used O large

  17. Determinants of Services Sourcing Performance

    Science.gov (United States)

    2010-12-16

    information (i.e., used to inform source selection decisions ) than as a means of continuous supplier improvement (Straight, 1999). Periodic ratings using a...to managing those services have not kept pace ( Ellram et al., 2007). Additionally, overworked services acquisition personnel often use supplier ...to the evaluation of suppliers , selection and award, payment and performance, and, finally, to contract closeout. Because this role is not

  18. Poverty - A Source of Conflict,

    Science.gov (United States)

    1980-08-25

    contend that poor coun- tries are likely to attack richer ones for the spoils of war, but rather that poverty is a breeding ground for instability. He...Studies Institute v POVERTY - A SOURCE OF CONFLICT The rich get richer; the poor get poorer. As this rule has applied to individuals, it has apparently...problems. These problems resulting from poverty create a dangerous threat to the stability of the world. This does not mean that poor countries will

  19. The Open Source Hardening Project

    Science.gov (United States)

    2009-07-01

    code on a recurring basis from more than 250 open popular source projects such as Firefox, Linux, and PHP . This represents 14,238 individual project...gcc) greatly simplifies debugging and error reporting. For exam- ple, all COREUTILS bugs were confirmed and fixed within two days and versions of the...making system calls fail outside of KLEE — we built a simple utility that uses the ptrace debugging interface to skip the system calls that were

  20. Review of terahertz semiconductor sources

    Institute of Scientific and Technical Information of China (English)

    Feng Wei

    2012-01-01

    Terahertz (THz) technology can be used in information science,biology,medicine,astronomy,and environmental science.THz sources are the key devices in THz applications.The author gives a brief review of THz semiconductor sources,such as GaAs1-xNx Gunn-like diodes,quantum wells (QWs) negative-effectivemass (NEM) THz oscillators,and the THz quantum cascade lasers (QCLs).THz current self-oscillation in doped GaAs1-xNx diodes driven by a DC electric field was investigated.The current self-oscillation is associated with the negative differential velocity effect in the highly nonparabolic conduction band of this unique material system.The current self-oscillations and spatiotemporal current patterns in QW NEM p+pp+ diodes was studied by considering scattering contributions from impurities,acoustic phonons,and optic phonons.It is indicated that both the applied bias and the doping concentration strongly influence the patterns and self-oscillating frequencies.The NEM p+pp+ diode may be used as an electrically tunable THz source.Meanwhile,by using the Monte Carlo method,the device parameters ofresonant-phonon THz QCLs were optimized.The results show that the calculated gain is more sensitive to the injection barrier width,the doping concentration,and the phonon extraction level separation,which is consistent with the experiments.

  1. Review of terahertz semiconductor sources

    Science.gov (United States)

    Wei, Feng

    2012-03-01

    Terahertz (THz) technology can be used in information science, biology, medicine, astronomy, and environmental science. THz sources are the key devices in THz applications. The author gives a brief review of THz semiconductor sources, such as GaAs1-xNx Gunn-like diodes, quantum wells (QWs) negative-effective-mass (NEM) THz oscillators, and the THz quantum cascade lasers (QCLs). THz current self-oscillation in doped GaAs1-xNx diodes driven by a DC electric field was investigated. The current self-oscillation is associated with the negative differential velocity effect in the highly nonparabolic conduction band of this unique material system. The current self-oscillations and spatiotemporal current patterns in QW NEM p+pp+ diodes was studied by considering scattering contributions from impurities, acoustic phonons, and optic phonons. It is indicated that both the applied bias and the doping concentration strongly influence the patterns and self-oscillating frequencies. The NEM p+pp+ diode may be used as an electrically tunable THz source. Meanwhile, by using the Monte Carlo method, the device parameters of resonant-phonon THz QCLs were optimized. The results show that the calculated gain is more sensitive to the injection barrier width, the doping concentration, and the phonon extraction level separation, which is consistent with the experiments.

  2. Exploiting dual otoacoustic emission sources

    Science.gov (United States)

    Abdala, Carolina; Kalluri, Radha

    2015-12-01

    Two distinct processes generate otoacoustic emissions (OAEs). Reflection-source emissions, here recorded as stimulus frequency OAEs, are optimally informative at low sound levels and are more sensitive to slight hearing loss; they have been linked to cochlear amplifier gain and tuning. Distortion-source emissions are strongest at moderate-high sound levels and persist despite mild hearing loss; they likely originate in the nonlinear process of hair cell transduction. In this preliminary study, we exploit the unique features of each by generating a combined reflection-distortion OAE profile in normal hearing and hearing-impaired ears. Distortion-product (DP) and stimulus-frequency (SF) OAEs were recorded over a broad range of stimulus levels and frequencies. Individual I/O and transfer functions were generated for both emission types in each ear, and OAE peak strength, compression threshold, and rate of compression were calculated. These combined SFOAE and DPOAE features in normal and hearing-impaired ears may provide a potentially informative and novel index of hearing loss. This is an initial step toward utilizing OAE source in characterizing cochlear function and dysfunction.

  3. Exploiting Dual Otoacoustic Emission Sources

    Science.gov (United States)

    Abdala, Carolina; Kalluri, Radha

    2016-01-01

    Two distinct processes generate otoacoustic emissions (OAEs). Reflection-source emissions, here recorded as stimulus frequency OAEs, are optimally informative at low sound levels and are more sensitive to slight hearing loss; they have been linked to cochlear amplifier gain and tuning. Distortion-source emissions are strongest at moderate-high sound levels and persist despite mild hearing loss; they likely originate in the nonlinear process of hair cell transduction. In this preliminary study, we exploit the unique features of each by generating a combined reflection-distortion OAE profile in normal hearing and hearing-impaired ears. Distortion-product (DP) and stimulus-frequency (SF) OAEs were recorded over a broad range of stimulus levels and frequencies. Individual I/O and transfer functions were generated for both emission types in each ear, and OAE peak strength, compression threshold, and rate of compression were calculated. These combined SFOAE and DPOAE features in normal and hearing-impaired ears may provide a potentially informative and novel index of hearing loss. This is an initial step toward utilizing OAE source in characterizing cochlear function and dysfunction. PMID:27695142

  4. Kernel current source density method.

    Science.gov (United States)

    Potworowski, Jan; Jakuczun, Wit; Lȩski, Szymon; Wójcik, Daniel

    2012-02-01

    Local field potentials (LFP), the low-frequency part of extracellular electrical recordings, are a measure of the neural activity reflecting dendritic processing of synaptic inputs to neuronal populations. To localize synaptic dynamics, it is convenient, whenever possible, to estimate the density of transmembrane current sources (CSD) generating the LFP. In this work, we propose a new framework, the kernel current source density method (kCSD), for nonparametric estimation of CSD from LFP recorded from arbitrarily distributed electrodes using kernel methods. We test specific implementations of this framework on model data measured with one-, two-, and three-dimensional multielectrode setups. We compare these methods with the traditional approach through numerical approximation of the Laplacian and with the recently developed inverse current source density methods (iCSD). We show that iCSD is a special case of kCSD. The proposed method opens up new experimental possibilities for CSD analysis from existing or new recordings on arbitrarily distributed electrodes (not necessarily on a grid), which can be obtained in extracellular recordings of single unit activity with multiple electrodes.

  5. A contaminação dos oceanos por radionuclídeos antropogênicos

    Directory of Open Access Journals (Sweden)

    Figueira Rubens C. L.

    1998-01-01

    Full Text Available Several hundreds of artificial radionuclides are produced as the result of human activities, such as the applications of nuclear reactors and particle accelerators, testing of nuclear weapons and nuclear accidents. Many of these radionuclides are short-lived and decay quickly after their production, but some of them are longer-lived and are released into the environment. From the radiological point of view the most important radionuclides are cesium-137, strontium-90 and plutonium-239, due to their chemical and nuclear characteristics. The two first radioisotopes present long half life (30 and 28 years, high fission yields and chemical behaviour similar to potassium and calcium, respectively. No stable element exists for plutonium-239, that presents high radiotoxicity, long half-life (24000 years and some marine organisms accumulate plutonium at high levels. The radionuclides introduced into marine environment undergo various physical, chemical and biological processes taking place in the sea. These processes may be due to physical dispersion or complicated chemical and biological interactions of the radionuclides with inorganic and organic suspend matter, variety of living organisms, bottom sediments, etc. The behaviour of radionuclides in the sea depends primarily on their chemical properties, but it may also be influenced by properties of interacting matrices and other environmental factors. The major route of radiation exposure of man to artificial radionuclides occuring in the marine environment is through ingestion of radiologically contamined marine organisms. This paper summarizes the main sources of contamination in the marine environment and presents an overview covering the oceanic distribution of anthropogenic radionuclides in the FAO regions. A great number of measurements of artificial radionuclides have been carried out on various marine environmental samples in different oceans over the world, being cesium-137 the most widely

  6. 21 CFR 640.60 - Source Plasma.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 7 2010-04-01 2010-04-01 false Source Plasma. 640.60 Section 640.60 Food and... ADDITIONAL STANDARDS FOR HUMAN BLOOD AND BLOOD PRODUCTS Source Plasma § 640.60 Source Plasma. The proper name of the product shall be Source Plasma. The product is defined as the fluid portion of human...

  7. When to make proprietary software open source

    NARCIS (Netherlands)

    Caulkins, J.P.; Feichtinger, G.; Grass, D.; Hartl, R.F.; Kort, P.M.; Seidl, A.

    2013-01-01

    Software can be distributed closed source (proprietary) or open source (developed collaboratively). While a firm cannot sell open source software, and so loses potential sales revenue, the open source software development process can have a substantial positive impact on the quality of a software, i

  8. CSNS H^- ion source test stand

    Institute of Scientific and Technical Information of China (English)

    吴小兵; 张俊嵩; 张华顺; 赵富祥; 欧阳华甫; 池云龙; 何伟; 黄涛; 李刚; 刘应满; 卢艳华; 徐韬光

    2011-01-01

    The Penning surface plasma source is adopted as the China Spallation Neutron Source (CSNS) H^- ion source. The designed energy and beam current of the source are 50 keV and 20 mA, respectively, with a normalized root mean square (norm. rms.) emittance of

  9. Characterization of ISOLDE ion source and ion source chemistry

    CERN Document Server

    Barbeau, Marion

    2014-01-01

    This report presents results of measurements made with the ISOLDE OFF-LINE mass separator [1]. The first part shows measurements of the ionization characteristics of noble gases in a VADIS ion source. The goal of the measurements was to determine the dependency of the extractable current of first and second noble gases ions with the electron energy. In the second part, investigation on in-target chemistry are presented. Here, the effect of injected sulfur hexafluoride ($SF_6$) on the release of oxygen from aluminium oxide ($Al_2 O_3$) was studied.

  10. Iranian Light Source Facility, A third generation light source laboratory

    Directory of Open Access Journals (Sweden)

    J Rahighi

    2015-09-01

    Full Text Available The Iranian Light Source Facility (ILSF project is the first large scale accelerator facility which is currently under planning in Iran. On the basis of the present design, circumference of the 3 GeV storage ring is 528 m. Beam current and natural beam emittance are 400 mA and 0.477 nm.rad, respectively. Some prototype accelerator components such as high power solid state radio frequency amplifiers, low level RF system, thermionic RF gun, H-type dipole and quadruple magnets, magnetic measurement laboratory and highly stable magnet power supplies have been constructed at ILSF R&D laboratory

  11. Practical open source software for libraries

    CERN Document Server

    Engard, Nicole

    2010-01-01

    Open source refers to an application whose source code is made available for use or modification as users see fit. This means libraries gain more flexibility and freedom than with software purchased with license restrictions. Both the open source community and the library world live by the same rules and principles. Practical Open Source Software for Libraries explains the facts and dispels myths about open source. Chapters introduce librarians to open source and what it means for libraries. The reader is provided with links to a toolbox full of freely available open source products to use in

  12. ALTERNATIVE SOURCES OF ENERGY - ALTERNATIVE SOURCES OF POLLUTION?

    Directory of Open Access Journals (Sweden)

    Marius-Razvan SURUGIU

    2007-06-01

    Full Text Available In many countries of the world investments are made for obtaining energy efficiency, pursuing to increase the generation of non-polluting fuels due to the fact that energy is vital for any economy. The increase in non-polluting fuels and in renewable energy generation might lead to diminishing the dependence of countries less endowed with conventional energy resources on oil and natural gas from Russia or from Arab countries. Nevertheless, environmental issues represent serious questions facing the mankind, requiring the identification, prevention, and why not, their total solving.European Union countries depend on imports of energy, especially on oil imports. At the same time, the European Union countries record a high volume of greenhouse gas emissions, substances adding to global warming. The transport sector is the main consumer of fossil fuels and generator of greenhouse gas emissions. Therefore, diversifying the energy supply used in the transport sector with less polluting sources is an essential objective of the European Union policy in the transport, energy and environment sector. Road transports’ is the sector recording the highest consumption of energy and the highest volume of greenhouse gas emissions.The use of ecologic fuels in the transport sector is an important factor for achieving the objectives of European policies in the field. It is yet to be seen to what extent alternative energy sources are damaging to the environment, as it is a known fact that even for them is recorded a certain level of negative externalities.

  13. Advanced Light Source control system

    Energy Technology Data Exchange (ETDEWEB)

    Magyary, S.; Chin, M.; Cork, C.; Fahmie, M.; Lancaster, H.; Molinari, P.; Ritchie, A.; Robb, A.; Timossi, C.

    1989-03-01

    The Advanced Light Source (ALS) is a third generation 1--2 GeV synchrotron radiation source designed to provide ports for 60 beamlines. It uses a 50 MeV electron linac and 1.5 GeV, 1 Hz, booster synchrotron for injection into a 1--2 GeV storage ring. Interesting control problems are created because of the need for dynamic closed beam orbit control to eliminate interaction between the ring tuning requirements and to minimize orbit shifts due to ground vibrations. The extremely signal sensitive nature of the experiments requires special attention to the sources of electrical noise. These requirements have led to a control system design which emphasizes connectivity at the accelerator equipment end and a large I/O bandwidth for closed loop system response. Not overlooked are user friendliness, operator response time, modeling, and expert system provisions. Portable consoles are used for local operation of machine equipment. Our solution is a massively parallel system with >120 Mbits/sec I/O bandwidth and >1500 Mips computing power. At the equipment level connections are made using over 600 powerful Intelligent Local Controllers (ILC-s) mounted in 3U size Eurocard slots using fiber-optic cables between rack locations. In the control room, personal computers control and display all machine variables at a 10 Hz rate including the scope signals which are collected though the control system. Commercially available software and industry standards are used extensively. Particular attention is paid to reliability, maintainability and upgradeability. 10 refs., 11 figs.

  14. Radiometry of flashing LED sources

    Science.gov (United States)

    Gregory, Don A.; Medley, Stephanie; Roberts, Adam

    2008-08-01

    A laboratory based technique has been devised for measuring the illumination characteristics of flashing light emitting diode (LED) sources. The difference between the photopic measurement of a continuous source and a flashing source is that some analytic method must be incorporated into the measurement to account for the response of the eye. Ohno et al have devised an analytic expression for the impulse response of the eye, which closely matches existing forms used for finding effective intensity1. These other forms are the Blondel-Rey equation, the Form Factor method, and the Allard method.4,5,6 Ohno's research suggests a modified Allard method, but offers no procedure for actually making the measurement. In this research, the modified Allard1 method approach has been updated using standard laboratory equipment such as a silicon detector in conjunction with a digital multi-meter and Labview® software to make this measurement. Labview® allows exact computation of the modified Allard method. However, an approximation scheme for the conversion from radiometric units to photopic units must be adopted. The LED spectral form is approximately a Gaussian line shape with full width at half maximum of about 15 to 30nm. The Gaussian curve makes converting from radiometric to photopic units difficult. To simplify, the technique presented here estimates the spectral form of the LEDs to be a Dirac delta function situated at the peak wavelength. This allows the conversion from watts to lumens to be a simple application of the luminous efficiency curve.2 For LEDs with a full width half maximum of 20nm, this scheme is found to be accurate to +/- 5%.

  15. Study of the leakage current of clinical dosimeters for teletherapy; Estudo da corrente de fuga de dosimetros clinicos para teleterapia

    Energy Technology Data Exchange (ETDEWEB)

    Damatto, Willian B.; Santos, Gelson P.; Potiens, Maria da Penha A.; Caldas, Linda V.E.; Vivolo, Vitor, E-mail: wbdamatto@ipen.b, E-mail: gpsantos@ipen.b, E-mail: mppalbu@ipen.b, E-mail: lcaldas@ipen.b, E-mail: vivolo@ipen.b [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2009-07-01

    This work demonstrates the importance of quality control of clinical dosemeters and therefore the equipment for radiotherapy treatment, exhibiting the necessary care related to answers and sensibilities and the possible defects of the clinical assembly

  16. 10 CFR 35.690 - Training for use of remote afterloader units, teletherapy units, and gamma stereotactic...

    Science.gov (United States)

    2010-01-01

    ...) Radiation physics and instrumentation; (B) Radiation protection; (C) Mathematics pertaining to the use and... an authorized user or authorized medical physicist, as appropriate, who is authorized for the...

  17. Methods for evaluating information sources

    DEFF Research Database (Denmark)

    Hjørland, Birger

    2012-01-01

    The article briefly presents and discusses 12 different approaches to the evaluation of information sources (for example a Wikipedia entry or a journal article): (1) the checklist approach; (2) classical peer review; (3) modified peer review; (4) evaluation based on examining the coverage...... of controversial views; (5) evidence-based evaluation; (6) comparative studies; (7) author credentials; (8) publisher reputation; (9) journal impact factor; (10) sponsoring: tracing the influence of economic, political, and ideological interests; (11) book reviews and book reviewing; and (12) broader criteria...

  18. The RHIC polarized source upgrade

    Energy Technology Data Exchange (ETDEWEB)

    Zelenski, A.; Atoian, G.; Davydenko, V.; Ivanov, A.; Kolmogorov, A.; Ritter, J.; Steski, D.; Zubets, V.

    2010-09-27

    The RHIC polarized H{sup -} ion source is being upgraded to higher intensity (5-10 mA) and polarization for use in the RHIC polarization physics program at enhanced luminosity RHIC operation. The higher beam peak intensity will allow reduction of the transverse beam emittance at injection to AGS to reduce polarization losses in AGS. There is also a planned RHIC luminosity upgrade by using the electron beam lens to compensate the beam-beam interaction at collision points. This upgrade is also essential for future BNL plans for a high-luminosity electron - proton (ion) Collider eRHIC.

  19. Astrophysics Source Code Library Enhancements

    CERN Document Server

    Hanisch, Robert J; Berriman, G Bruce; DuPrie, Kimberly; Mink, Jessica; Nemiroff, Robert J; Schmidt, Judy; Shamir, Lior; Shortridge, Keith; Taylor, Mark; Teuben, Peter J; Wallin, John

    2014-01-01

    The Astrophysics Source Code Library (ASCL; ascl.net) is a free online registry of codes used in astronomy research; it currently contains over 900 codes and is indexed by ADS. The ASCL has recently moved a new infrastructure into production. The new site provides a true database for the code entries and integrates the WordPress news and information pages and the discussion forum into one site. Previous capabilities are retained and permalinks to ascl.net continue to work. This improvement offers more functionality and flexibility than the previous site, is easier to maintain, and offers new possibilities for collaboration. This presentation covers these recent changes to the ASCL.

  20. Hybrid-Source Impedance Networks

    DEFF Research Database (Denmark)

    Li, Ding; Gao, Feng; Loh, Poh Chiang;

    2010-01-01

    the cascaded networks would have a higher output voltage gain and other unique advantages that currently have not been investigated yet. It is anticipated that these advantages would help the formed inverters find applications in photovoltaic and other renewable systems, where a high voltage gain is usually......Hybrid-source impedance networks have attracted attention among researchers because of their flexibility in performing buck-boost energy conversion. To date, three distinct types of impedance networks can be summarized for implementing voltage-type inverters with another three types summarized...

  1. Improvement of penning ion sources

    CERN Document Server

    Bizyukov, A A; Kashaba, A Y; Sereda, K N

    2000-01-01

    It is shown that the loss of a longitudinal symmetry of magnetic field distribution in respect to the centre of the Penning discharge system causes change of electrostatic potential distribution in the discharge gap leads to appearance of asymmetry of current magnitude to the cathodes of the Penning cell,change of magnitude of current density and energy distribution of the ion beam extracted in a longitudinal direction.The use of an inhomogeneous magnetic field which is longitudinally asymmetrical concerning electrodes of the system allows to increase current efficiency of Penning ion sources from 0,2 to 0,55.

  2. Leveraging External Sources of Innovation

    DEFF Research Database (Denmark)

    West, Joel; Bogers, Marcel

    2014-01-01

    own specific set of mechanisms and conditions. Integrating innovations has been mostly studied from an absorptive capacity perspective, with less attention given to the impact of competencies and culture (including “not invented here”). Commercializing innovations puts the most emphasis on how......” in a way inconsistent with earlier definitions in innovation management. The paper concludes with recommendations for future research that include examining the end-to-end innovation commercialization process, and studying the moderators and limits of leveraging external sources of innovation....

  3. Redshift Properties of MASIV Sources

    Science.gov (United States)

    2010-06-01

    prerequisite. For optical identification we used mainly the Sloan Digital Sky Survey ( SDSS DR 5 Adelman-McCarthy et aJ. 2007) and GSC 2.3 (Lasker et...aJ. 2008). 165 sources werc identified from the SDSS DR5, which is complcte down to r=22.5 (Aef! rv6230A) with astrometric accuracy about (1.𔃻...than the SDSS . The new redshift were obtained using the 2.56 m Nordic Optical Telescope ·(NOT) which is locatcd at La Palma and the 5 m Palomar Hale

  4. LINAC4 - The Ion Source

    CERN Document Server

    Haugaa, Olav

    2013-01-01

    My summer student project has been split in three parts. During the first 4-5 weeks I was involved in the design of the filtermagnets for the IS02 with the simulation tool Opera. After this, I have performed data analysis of the plasma light emission in the IS01 source with the software Matlab and I took part in the development of a Fortran code for plasma simulations. In all projects, understanding plasma physics has been essential and the learning outcome related to this field has been very high.

  5. High intensity polarized electron sources

    Energy Technology Data Exchange (ETDEWEB)

    Sinclair, C.K.

    1980-10-01

    The status of the polarized electron source development program at SLAC will be reviewed. Emission currents of 60 A, corresponding to a space charge limited current density of 180 A/cm/sup 2/, have been obtained from GaAs photocathodes. Electron beam polarization 20% greater than that obtainable from GaAs cathodes has been observed from multilayer GaAs-GaAlAs structures. Work in progress to produce high beam polarization from II-IV-V/sub 2/ chalcopyrite photocathodes will also be described.

  6. Detecting fission from special nuclear material sources

    Science.gov (United States)

    Rowland, Mark S.; Snyderman, Neal J.

    2012-06-05

    A neutron detector system for discriminating fissile material from non-fissile material wherein a digital data acquisition unit collects data at high rate, and in real-time processes large volumes of data directly into information that a first responder can use to discriminate materials. The system comprises counting neutrons from the unknown source and detecting excess grouped neutrons to identify fission in the unknown source. The system includes a graphing component that displays the plot of the neutron distribution from the unknown source over a Poisson distribution and a plot of neutrons due to background or environmental sources. The system further includes a known neutron source placed in proximity to the unknown source to actively interrogate the unknown source in order to accentuate differences in neutron emission from the unknown source from Poisson distributions and/or environmental sources.

  7. Adjuvant radiotherapy in early stage endometrial cancer Radioterapia adjuvante para câncer do endométrio estádio inicial

    Directory of Open Access Journals (Sweden)

    Antonio Carlos Zuliani

    2011-08-01

    Full Text Available OBJECTIVE: To compare the rates of overall survival (OS, disease-free survival (DFS and toxicity in different techniques of postoperative radiotherapy for stage IA endometrioid adenocarcionoma of endometrium, histological grades 1and 2. METHODS: A historical comparison between treatment regimens was performed, and 133 women with a minimum follow-up of 5 years were included. Teletherapy (TELE group, with 22 patients treated from 1988 to 1996, with a 10 MV linear accelerator, average dose 46.2 Gy. Low dose rate brachytherapy (LDRB group was performed between 1992 and 1995, in 19 women, with an insertion of Cesium 137, at a 60 Gy dose. Fourteen women operated between 1990 and 1996 did not receive radiotherapy (NO RT group. High dose rate brachytherapy was performed in 78 patients (HDRB group, from 1996 to 2004, in five weekly 7 Gy insertions, prescribed at 0.5 cm from the vaginal cylinder. RESULTS: The 5-year disease-free survival was 94.6% for the HDRB group, 94.1% for the LDRB group, 100% for the TELE group and NO RT groups (p = 0.681. The 5-year overall survival was 86.6% for the HDRB group, 89.5% for the LDRB group and 90% for the TELE group and NO RT groups (p = 0.962. Grades 3-5 late toxicity was 5.3% in LDRB group and 27.3% for the TELE group (p < 0.001. CONCLUSION: Patients submitted to adjuvant teletherapy showed very high toxicity, which contraindicates that treatment for those patients. There may be a role for adjuvant HDRB, but randomized controlled trials are still needed to evaluate its benefit.OBJETIVO: Comparar as taxas de sobrevida global (SG, sobrevida livre de doença (DFS e de toxicidade em diferentes técnicas de radioterapia pós-operatória para adenocarcionoma endometrioide do endométrio estádio IA, graus histológicos 1 e 2. MéTODOS: Realizou-se uma comparação histórica entre regimes de tratamento, incluindo 133 mulheres com seguimento mínimo de cinco anos. Teleterapia (grupo TELE, com 22 pacientes, de 1988 a 1996

  8. Soybean, a promising health source.

    Science.gov (United States)

    Mateos-Aparicio, I; Redondo Cuenca, A; Villanueva-Suárez, M J; Zapata-Revilla, M A

    2008-01-01

    Health properties and uses of soybean, as well as the different chemical and botanical characteristics of this legume are shown in this review. Soybean represents an excellent source of high quality protein, it has a low content in saturated fat, it contains a great amount of dietary fibre and its isoflavone content makes it singular among other legumes. Many researches have been carried out into the benefits of legumes: chickpeas, beans, lentils and soy, among others, but characterization and positive health effects of soybeans have been recently studied. The interest in this legume has increased because of its functional components. Most of the studies have been focused on soybean protein as a possible source of prevention against cardiovascular disease. This positive effect may be due to a decrease in serum cholesterol concentrations. In addition, there are many studies on isoflavones, non-nutritive substances, associated with prevention and treatment of different chronic diseases. Moreover, some studies have shown the health properties of soy dietary fibre. Therefore, it would be interesting to consider the replacement of animal based foods for soybean foods in order to obtain some nutritional benefits.

  9. DHAid™ – The vegetarian source

    Directory of Open Access Journals (Sweden)

    Freitas Ulla

    2008-07-01

    Full Text Available In humans, DHA occurs naturally as a cell membrane fatty acid in the brain, retina, testes and sperm, and has been reported to be essential in the development of these organs and cells. There it is crucial for the functioning of embedded proteins, i.e. rhodopsin for vision and postsynaptic receptors for neurotransmission. In phospholipids in general, DHA contributes to membrane properties such as fluidity, flexibility and permeability. A deficiency in DHA can lead to memory loss, learning disabilities and impaired visual acuity. Limited storage of DHA in adipose tissue suggests that a continuous supply is needed. These facts clearly demonstrate the physiological importance of DHA for humans and have resulted, for example, in the recommendation of increasing dietary intake of DHA during pregnancy and lactation. Also in the maintenance of cardiovascular health, DHA plays an important role. DHAid™ is a pure vegetarian source of omega-3 docosahexaenoic acid (DHA. It is produced from microalgae in a controlled process in fermentation vessels by the Swiss life-science company Lonza. Due to its renewable sources, DHAid™ is environmentally friendly. DHAid™ is allergen free and is free of potential contaminants that are discussed for seafood.

  10. Environmental source of arsenic exposure.

    Science.gov (United States)

    Chung, Jin-Yong; Yu, Seung-Do; Hong, Young-Seoub

    2014-09-01

    Arsenic is a ubiquitous, naturally occurring metalloid that may be a significant risk factor for cancer after exposure to contaminated drinking water, cigarettes, foods, industry, occupational environment, and air. Among the various routes of arsenic exposure, drinking water is the largest source of arsenic poisoning worldwide. Arsenic exposure from ingested foods usually comes from food crops grown in arsenic-contaminated soil and/or irrigated with arsenic-contaminated water. According to a recent World Health Organization report, arsenic from contaminated water can be quickly and easily absorbed and depending on its metabolic form, may adversely affect human health. Recently, the US Food and Drug Administration regulations for metals found in cosmetics to protect consumers against contaminations deemed deleterious to health; some cosmetics were found to contain a variety of chemicals including heavy metals, which are sometimes used as preservatives. Moreover, developing countries tend to have a growing number of industrial factories that unfortunately, harm the environment, especially in cities where industrial and vehicle emissions, as well as household activities, cause serious air pollution. Air is also an important source of arsenic exposure in areas with industrial activity. The presence of arsenic in airborne particulate matter is considered a risk for certain diseases. Taken together, various potential pathways of arsenic exposure seem to affect humans adversely, and future efforts to reduce arsenic exposure caused by environmental factors should be made.

  11. Independent EEG sources are dipolar.

    Directory of Open Access Journals (Sweden)

    Arnaud Delorme

    Full Text Available Independent component analysis (ICA and blind source separation (BSS methods are increasingly used to separate individual brain and non-brain source signals mixed by volume conduction in electroencephalographic (EEG and other electrophysiological recordings. We compared results of decomposing thirteen 71-channel human scalp EEG datasets by 22 ICA and BSS algorithms, assessing the pairwise mutual information (PMI in scalp channel pairs, the remaining PMI in component pairs, the overall mutual information reduction (MIR effected by each decomposition, and decomposition 'dipolarity' defined as the number of component scalp maps matching the projection of a single equivalent dipole with less than a given residual variance. The least well-performing algorithm was principal component analysis (PCA; best performing were AMICA and other likelihood/mutual information based ICA methods. Though these and other commonly-used decomposition methods returned many similar components, across 18 ICA/BSS algorithms mean dipolarity varied linearly with both MIR and with PMI remaining between the resulting component time courses, a result compatible with an interpretation of many maximally independent EEG components as being volume-conducted projections of partially-synchronous local cortical field activity within single compact cortical domains. To encourage further method comparisons, the data and software used to prepare the results have been made available (http://sccn.ucsd.edu/wiki/BSSComparison.

  12. Light Sources and Lighting Circuits

    Science.gov (United States)

    Honda, Hisashi; Suwa, Takumi; Yasuda, Takeo; Ohtani, Yoshihiko; Maehara, Akiyoshi; Okada, Atsunori; Komatsu, Naoki; Mannami, Tomoaki

    According to the Machinery Statistics of the Ministry of Economy, Trade and Industry, the production of incandescent lamps in Japan in 2007 was 990 million units (90.0% of the previous year's total), in which the production of incandescent lamps for general lighting was 110 million units (90.0% of the previous year's total) and of tungsten-halogen lamps was 44 million units (96.6% of the previous year's total). The production of fluorescent lamps was 927 million units (93.9% of the previous year's total), in which general fluorescent lamps, excluding those for LCD back lighting, was 320 million units (87.2% of the previous year's total). Also, the production of HID lamps was 10 million units (101.5% of the previous year's total). On the other hand, when the numbers of sales are compared with the sales of the previous year, incandescent lamps for general use was 99.8%, tungsten-halogen lamps was 96.9%, fluorescent lamps was 95.9%, and HID lamps was 98.9%. Self-ballasted fluorescent lamps alone showed an increase in sales as strong as 29 million units, or 121.7% of the previous year's sales. It is considered that the switchover of incandescent lamps to HID lamps was promoted for energy conservation and carbon dioxide reduction with the problem of global warming in the background. In regard to exhibitions, Lighting Fair 2007 was held in Tokyo in March, and LIGHTFAIR INTERNATIONAL 2007 was held in New York in May. Regarding academic conferences, LS:11 (the 11th International Symposium on the Science & Technology of Light Sources) was held in Shanghai in May, and the First International Conference on White LEDs and Solid State Lighting was held in Tokyo in November. Both conferences suggested that there are strong needs and concerns now about energy conservation, saving natural resources, and restrictions of hazardous materials. In regard to incandescent lamps, the development of products aiming at higher efficacy, electric power savings, and longer life was advanced by

  13. CSNS H- ion source test stand

    Institute of Scientific and Technical Information of China (English)

    WU Xiao-Bing; ZHANG Jun-Song; ZHANG Hua-Shun; ZHAO Fu-Xiang; OUYANG Hua-Fu; CHI Yun-Long; HE Wei; HUANG Tao; LI Gang; LIU Ying-Man; LU Yan-Hua; XU Tao-Guang

    2011-01-01

    The Penning surface plasma source is adopted as the China Spallation Neutron Source (CSNS) H- ion source. The designed energy and beam current of the source are 50 keV and 20 mA, respectively, with a normalized root mean square(norm·rms.)emittance of 0.2πmm·mrad.The construction of a H-ion source test stand has been completed, and the commissioning of the source is in progress. Stable H- ion beams with energy of 50 keV and current up to 50 mA are attained. Emittance measurement for the H- beam is being prepared.

  14. Cepstrum analysis of seismic source characteristics

    Institute of Scientific and Technical Information of China (English)

    魏富胜; 黎明

    2003-01-01

    This paper introduces the concept of cepstrum. By investigating the difference in source characteristics between earthquakes and explosions the paper infers the manifestation of source difference in various variable domains, and seeks for effective means to express such source difference. Extending the approach of source discrimination from time and frequency domain to the cepstrum domain, the paper proposes a method of cepstrum analysis for recognizing the characteristics of seismic sources and establishes criteria for identifying the type of seismic sources. Cepstrum analysis on some recent earthquakes and explosions has been made, and the result shows that the method is quite effective in practice.

  15. Experimental study on partial coherence source

    CERN Document Server

    Zhao Xue Qing; Yuan Xiao; LiuJingRu; Wang Long Hua; Tang Ying; Huang, Kerson

    2002-01-01

    Partial coherence source is a key part in the laser system using echelon-free introduced spatial incoherence beam smoothing technique. Different kinds of partial coherence sources have been studied experimentally for improving the uniformity of laser intensity distribution. It is found that the source produced by excimer laser scattering on the surface of a teflon plate is ideal. The properties of this kind of source are studied. As a result, the uniformity of source beam intensity distribution, the beam spatial coherence and energy transfer efficiency of the source are obtained

  16. The DCU laser ion source.

    Science.gov (United States)

    Yeates, P; Costello, J T; Kennedy, E T

    2010-04-01

    Laser ion sources are used to generate and deliver highly charged ions of various masses and energies. We present details on the design and basic parameters of the DCU laser ion source (LIS). The theoretical aspects of a high voltage (HV) linear LIS are presented and the main issues surrounding laser-plasma formation, ion extraction and modeling of beam transport in relation to the operation of a LIS are detailed. A range of laser power densities (I approximately 10(8)-10(11) W cm(-2)) and fluences (F=0.1-3.9 kJ cm(-2)) from a Q-switched ruby laser (full-width half-maximum pulse duration approximately 35 ns, lambda=694 nm) were used to generate a copper plasma. In "basic operating mode," laser generated plasma ions are electrostatically accelerated using a dc HV bias (5-18 kV). A traditional einzel electrostatic lens system is utilized to transport and collimate the extracted ion beam for detection via a Faraday cup. Peak currents of up to I approximately 600 microA for Cu(+) to Cu(3+) ions were recorded. The maximum collected charge reached 94 pC (Cu(2+)). Hydrodynamic simulations and ion probe diagnostics were used to study the plasma plume within the extraction gap. The system measured performance and electrodynamic simulations indicated that the use of a short field-free (L=48 mm) region results in rapid expansion of the injected ion beam in the drift tube. This severely limits the efficiency of the electrostatic lens system and consequently the sources performance. Simulations of ion beam dynamics in a "continuous einzel array" were performed and experimentally verified to counter the strong space-charge force present in the ion beam which results from plasma extraction close to the target surface. Ion beam acceleration and injection thus occur at "high pressure." In "enhanced operating mode," peak currents of 3.26 mA (Cu(2+)) were recorded. The collected currents of more highly charged ions (Cu(4+)-Cu(6+)) increased considerably in this mode of operation.

  17. Capillary Discharge XUV Radiation Source

    Directory of Open Access Journals (Sweden)

    M. Nevrkla

    2009-01-01

    Full Text Available A device producing Z-pinching plasma as a source of XUV radiation is described. Here a ceramic capacitor bank pulse-charged up to 100 kV is discharged through a pre-ionized gas-filled ceramic tube 3.2 mm in diameter and 21 cm in length. The discharge current has amplitude of 20 kA and a rise-time of 65 ns. The apparatus will serve as experimental device for studying of capillary discharge plasma, for testing X-ray optics elements and for investigating the interaction of water-window radiation with biological samples. After optimization it will be able to produce 46.9 nm laser radiation with collision pumped Ne-like argon ions active medium. 

  18. Laser sources for lidar applications

    Science.gov (United States)

    Kilmer, J.; Iadevaia, A.; Yin, Y.

    2012-06-01

    Advanced LIDAR applications such as next gen: Micro Pulse; Time of Flight (e.g., Satellite Laser Ranging); Coherent and Incoherent Doppler (e.g., Wind LIDAR); High Spectral Resolution; Differential Absorption (DIAL); photon counting LIDAR (e.g., 3D LIDAR); are placing more demanding requirements on conventional lasers (e.g., increased rep rates, etc.) and have inspired the development of new types of laser sources. Today, solid state lasers are used for wind sensing, 2D laser Radar, 3D scanning and flash LIDAR. In this paper, we report on the development of compact, highly efficient, high power all-solidstate diode pulsed pumped ns lasers, as well as, high average power/high pulse energy sub nanosecond (picosecond (lasers for these next gen LIDAR applications.

  19. Photonic MEMS tunable laser sources

    Institute of Scientific and Technical Information of China (English)

    LIU Ai-qun

    2009-01-01

    This article covers laser configurations, design and experiments of photonic microelectromechanical systems (MEMS) tunable laser sources. Three different types of MEMS tunable lasers such as MEMS coupled-cavity lasers, injection-locked laser systems and dual-wavelength tunable lasers are demonstrated as examples of natural synergy of MEMS with photonics. The expansion and penetration of the MEMS technology to silicon optoelectronic creates on-chip optical systems at an unprecedented scale of integration. While producing better integration with robustness and compactness, MEMS improves the functionalities and specifications of laser chips. Additionally, MEMS tunable lasers are featured with small size, high tuning speed, wide tuning range and CMOS compatible integration, which broaden their applications to many fields.

  20. Renewable energy sources; Erneuerbare Energien

    Energy Technology Data Exchange (ETDEWEB)

    Lenz, Volker [Deutsches BiomasseForschungsZentrum gGmbH (DBFZ), Leipzig (Germany); Kaltschmitt, Martin [Technische Univ. Hamburg-Harburg, Hamburg (Germany). Inst. fuer Umwelttechnik und Energiewirtschaft

    2012-07-01

    The development of the use of renewable energy sources in Germany in 2011 significantly was influenced by the disaster in Fukushima (Japan) and the change of course in the German energy policy. In addition, there is the amendment of the Renewable Energy Law (EEG) in an increasingly controversial area of tension between climate protection, energy utilization, cost minimization and considerations on sustainability. With this in mind, the authors of the contribution under consideration report on developments in Germany in the year 2011 in the field of energy supply and fuel supply from renewable energies. Beside the energy-economic framework conditions for the various possibilities for the use of renewable energies, the current status, developments and prospects are analysed. The contribution gives an outlook on the possible expansion of the supply of renewable energies in 2012.

  1. Organising purchasing and (strategic) sourcing

    DEFF Research Database (Denmark)

    Lidegaard, Nina; Boer, Harry; Munkgaard Møller, Morten

    2015-01-01

    mature role in corporate strategy. These changes have serious implications for the purchasing process, its characteristics and organisation. Previous research indicates that none of the prevailing solutions, functional departments and cross-functional teams, embedded in a centralised, decentralised......The role of purchasing has changed over the past two to three decades. The focus is no longer limited to purchasing manufacturing inputs, but also includes sourcing of innovations from, and even co-developing technologies together with, suppliers. Furthermore, purchasing has obtained a much more...... or hybrid overall structure, deliver the expected results. Contingency theory predicts that the success of a firm depends on the fit among characteristics of, amongst others, the firm’s processes and organisational structure. The objective of this paper is to propose and illustrate a processbased...

  2. Multiple source ground heat storage

    Science.gov (United States)

    Belzile, P.; Lamarche, L.; Rousse, D. R.

    2016-09-01

    Sharing geothermal borefields is usually done with each borehole having the same inlet conditions (flow rate, temperature and fluid). The objective of this research is to improve the energy efficiency of shared and hybrid geothermal borefields by segregating heat transfer sources. Two models are briefly presented: The first model allows the segregation of the inlet conditions for each borefields; the second model allows circuits to be defined independently for each leg of double U-tubes in a borehole. An application couples residential heat pumps and arrays of solar collectors. Independent circuits configuration gave the best energy savings in a symmetric configuration, the largest shank spacing and with solar collectors functioning all year long. The boreholes have been shortened from 300 m to 150 m in this configuration.

  3. Source mechanisms of volcanic tsunamis.

    Science.gov (United States)

    Paris, Raphaël

    2015-10-28

    Volcanic tsunamis are generated by a variety of mechanisms, including volcano-tectonic earthquakes, slope instabilities, pyroclastic flows, underwater explosions, shock waves and caldera collapse. In this review, we focus on the lessons that can be learnt from past events and address the influence of parameters such as volume flux of mass flows, explosion energy or duration of caldera collapse on tsunami generation. The diversity of waves in terms of amplitude, period, form, dispersion, etc. poses difficulties for integration and harmonization of sources to be used for numerical models and probabilistic tsunami hazard maps. In many cases, monitoring and warning of volcanic tsunamis remain challenging (further technical and scientific developments being necessary) and must be coupled with policies of population preparedness.

  4. Control System of the H~- Ion Source

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    <正>The control system is of primary importance to the accelerator operation. This paper presents a brief introduction to the new ion source control system. The research is to build a new H- ion source based on

  5. Driver circuit for solid state light sources

    Energy Technology Data Exchange (ETDEWEB)

    Palmer, Fred; Denvir, Kerry; Allen, Steven

    2016-02-16

    A driver circuit for a light source including one or more solid state light sources, a luminaire including the same, and a method of so driving the solid state light sources are provided. The driver circuit includes a rectifier circuit that receives an alternating current (AC) input voltage and provides a rectified AC voltage. The driver circuit also includes a switching converter circuit coupled to the light source. The switching converter circuit provides a direct current (DC) output to the light source in response to the rectified AC voltage. The driver circuit also includes a mixing circuit, coupled to the light source, to switch current through at least one solid state light source of the light source in response to each of a plurality of consecutive half-waves of the rectified AC voltage.

  6. Problems with packaged sources in foreign countries

    Energy Technology Data Exchange (ETDEWEB)

    Abeyta, Cristy L [Los Alamos National Laboratory; Matzke, James L [Los Alamos National Laboratory; Zarling, John [Los Alamos National Laboratory; Tompkin, J. Andrew [Los Alamos National Laboratory

    2010-01-01

    The Global Threat Reduction Initiative's (GTRI) Off-Site Source Recovery Project (OSRP), which is administered by the Los Alamos National Laboratory (LANL), removes excess, unwanted, abandoned, or orphan radioactive sealed sources that pose a potential threat to national security, public health, and safety. In total, GTRI/OSRP has been able to recover more than 25,000 excess and unwanted sealed sources from over 825 sites. In addition to transuranic sources, the GTRI/OSRP mission now includes recovery of beta/gamma emitting sources, which are of concern to both the U.S. government and the International Atomic Energy Agency (IAEA). This paper provides a synopsis of cooperative efforts in foreign countries to remove excess and unwanted sealed sources by discussing three topical areas: (1) The Regional Partnership with the International Atomic Energy Agency; (2) Challenges in repatriating sealed sources; and (3) Options for repatriating sealed sources.

  7. Sole Source Aquifers for NY and NJ

    Data.gov (United States)

    U.S. Environmental Protection Agency — This layer is the designated sole source aquifers of New York and New Jersey. A Sole Source Aquifer, is an aquifer that supplies 50% or more of the drinking water...

  8. Cascaded trans-z-source inverters

    DEFF Research Database (Denmark)

    Li, Ding; Loh, Poh Chiang; Zhu, Miao;

    2011-01-01

    Z-source inverter is a recently proposed single-stage inverter with added voltage-boost capability for complementing the usual voltage-buck operation of a traditional voltage-source inverter. As long as the transformer element added in to the z-source concept, a trans-z-source inverter with one...... transformer and one capacitor is reported recently. This paper has adapted the cascaded concept into the trans-z-source and trans-quasi-z-source inverters to extend each to the cascaded topologies before combination is made with allowing more sources embedded which reduces the capacitor voltage and enhanced...... the compatibility for distributed sources. Unlike existing techniques, voltage stresses within the proposed inverters are better distributed among the passive components. Theoretical analysis for explaining these operating features has already been discussed before simulation were performed and an experimental...

  9. Plasma Cathode Electron Sources Physics, Technology, Applications

    CERN Document Server

    Oks, Efim

    2006-01-01

    This book fills the gap for a textbook describing this kind of electron beam source in a systematic and thorough manner: from physical processes of electron emission to examples of real plasma electron sources and their applications.

  10. LAT Monitored Source List Light Curves

    Data.gov (United States)

    National Aeronautics and Space Administration — The LAT team monitors flux values for a number of bright sources and transient sources that have shown flares during the mission. (See up-to-date weekly reports on...

  11. Food Sources of Important Nutrients (for Vegetarians)

    Science.gov (United States)

    ... For Women For Seniors Food Sources of 5 Important Nutrients for Vegetarians Reviewed by Taylor Wolfram, MS, ... each meal increases iron absorption. Sources include: Fortified breakfast cereals Soybeans Some dark leafy greens including spinach ...

  12. Polarized ion source operation at IUCF

    Energy Technology Data Exchange (ETDEWEB)

    Derenchuk, V. [Indiana University Cyclotron Facility, Bloomington, Indiana 47408 (United States); Belov, A. [Institute for Nuclear Research of the Russian Academy of Sciences, Moscow, 117312, Russian Federation (Russian Federation); Brown, R.; Collins, J.; Sowinski, J.; Stephenson, E.; Wedekind, M. [Indiana University Cyclotron Facility, Bloomington, Indiana 47408 (United States)

    1995-07-15

    The IUCF high intensity polarized ion source (HIPIOS), based on the source in operation at TUNL (1) and employing cold ({similar_to}30 K) atomic beam technology with an electron cyclotron resonance ionizer, has recently delivered beam to the first users. The results of the development work required to make the source operate reliably, with reasonable beam parameters are described. Methods used to measure the polarization and possible sources of unpolarized background are also discussed.

  13. How to tap Mexican Business Information Sources

    OpenAIRE

    1993-01-01

    Publication of business information sources in Mexico is growing fast. This growth is probably faster than the one of traditional academic-oriented sources. However, despite this growth, Mexican companies and international corporations demand greater and better information sources to monitor their environments due to the free trade agreement with The US and Canada. An evaluation of the most important sources and organizations devoted to the publication of business information are included...

  14. High Energy Sources Observed with OMC

    CERN Document Server

    Risquez, D; Mas-Hesse, J M; Kuulkers, E

    2008-01-01

    The INTEGRAL Optical Monitoring Camera, OMC, has detected many high energy sources. We have obtained V-band fluxes and light curves for their counterparts. In the cases of previously unknown counterparts, we have searched for characteristic variations in optical sources around the high-energy target position. Results about the Galactic Bulge Monitoring, INTEGRAL Gamma-Ray sources (IGR), and other high energy sources are presented.

  15. Off-Site Source Recovery Project Overview.

    Energy Technology Data Exchange (ETDEWEB)

    Coel-Roback, Rebecca J. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-09-29

    This report introduces the Off-Site Source Recovery project and gives a summary of domestic and international work. The mission of OSRP is to eliminate excess, unwanted, abandoned, or orphan radioactive sealed sources that pose a potential risk to health, safety, and national security. OSRP identifies and tracks disused sealed sources potentially requiring recovery, and performs special form encapsulation for sealed sources to simplify transportation.

  16. Highly efficient sources of single indistinguishable photons

    DEFF Research Database (Denmark)

    Gregersen, Niels

    2013-01-01

    Solid-state sources capable of emitting single photons on demand are of great interest in quantum information applications. Ideally, such a source should emit exactly one photon into the collection optics per trigger, the emitted photons should be indistinguishable and the source should...

  17. 30 CFR 57.4500 - Heat sources.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Heat sources. 57.4500 Section 57.4500 Mineral... HEALTH SAFETY AND HEALTH STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Fire Prevention and Control Installation/construction/maintenance § 57.4500 Heat sources. Heat sources capable of producing...

  18. 30 CFR 56.4500 - Heat sources.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Heat sources. 56.4500 Section 56.4500 Mineral... HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Fire Prevention and Control Installation/construction/maintenance § 56.4500 Heat sources. Heat sources capable of producing...

  19. Supercontinuum Lightwave Sources for Photonic Networks

    Institute of Scientific and Technical Information of China (English)

    Kunihiko Mori

    2003-01-01

    WDM optical sources based on supercontinuum (SC) generation are reviewed. The design of an SC lightwave source is described that uses a scaling rule among the parameters in an SC generating fiber and a seed optical pulse. Finally,recent efforts to apply SC lightwave source to optical network systems are mentioned.

  20. Supercontinuum Lightwave Sources for Photonic Networks

    Institute of Scientific and Technical Information of China (English)

    Kunihiko; Mori

    2003-01-01

    WDM optical sources based on supercontinuum (SC) generation are reviewed. The design of an SC lightwave source is described that uses a scaling rule among the parameters in an SC generating fiber and a seed optical pulse. Finally, recent efforts to apply SC lightwave source to optical network systems are mentioned.

  1. Apparel Sourcing Will Shine in Paris

    Institute of Scientific and Technical Information of China (English)

    Wang Ting

    2011-01-01

    This September, Messe Frankfurt France would stage a new international platform for apparel and fashion accessories sourcing, Apparel Sourcing (App), for the first time in Paris. First launched in the US in 2010, the French edition of Apparel Sourcing wou

  2. Source Region Identification Using Kernel Smoothing

    Science.gov (United States)

    As described in this paper, Nonparametric Wind Regression is a source-to-receptor source apportionment model that can be used to identify and quantify the impact of possible source regions of pollutants as defined by wind direction sectors. It is described in detail with an exam...

  3. Websites for Primary Sources and Civics Education

    Science.gov (United States)

    Rulli, Daniel

    2005-01-01

    This article features a list of websites for primary sources and civics education. The World Wide Web has become an excellent source for facsimiles, images, and transcriptions of primary sources. As it would be impossible to provide a comprehensive list of all the sites, this annotated list highlights selective sites that provide access to…

  4. Trellis-based source and channel coding

    NARCIS (Netherlands)

    Van der Vleuten, R.J.

    1994-01-01

    This thesis concerns the efficient transmission of digital data, such as digitized sounds or images, from a source to its destination. To make the best use of the limited capacity of the source-destination channel, a source coder is used to delete the less significant information. To correct the occ

  5. Learning the Semantics of Structured Data Sources

    Science.gov (United States)

    Taheriyan, Mohsen

    2015-01-01

    Information sources such as relational databases, spreadsheets, XML, JSON, and Web APIs contain a tremendous amount of structured data, however, they rarely provide a semantic model to describe their contents. Semantic models of data sources capture the intended meaning of data sources by mapping them to the concepts and relationships defined by a…

  6. Monte Carlo simulation of gamma ray tomography for image reconstruction

    Energy Technology Data Exchange (ETDEWEB)

    Guedes, Karlos A.N.; Moura, Alex; Dantas, Carlos; Melo, Silvio; Lima, Emerson, E-mail: karlosguedes@hotmail.com [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil); Meric, Ilker [University of Bergen (Norway)

    2015-07-01

    The Monte Carlo simulations of known density and shape object was validate with Gamma Ray Tomography in static experiments. An aluminum half-moon piece placed inside a steel pipe was the MC simulation test object that was also measured by means of gamma ray transmission. Wall effect of the steel pipe due to irradiation geometry in a single pair source-detector tomography was evaluated by comparison with theoretical data. MCNPX code requires a defined geometry to each photon trajectory which practically prevents this usage for tomography reconstruction simulation. The solution was found by writing a program in Delphi language to create input files automation code. Simulations of tomography data by automated MNCPX code were carried out and validated by experimental data. Working in this sequence the produced data needed a databank to be stored. Experimental setup used a Cesium-137 isotopic radioactive source (7.4 × 109 Bq), and NaI(Tl) scintillation detector of (51 × 51) × 10−3 m crystal size coupled to a multichannel analyzer. A stainless steel tubes of 0,154 m internal diameter, 0.014 m thickness wall. The results show that the MCNPX simulation code adapted to automated input file is useful for generating a matrix data M(θ,t), of a computerized gamma ray tomography for any known density and regular shape object. Experimental validation used RMSE from gamma ray paths and from attenuation coefficient data. (author)

  7. 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.

  8. From reactors to long pulse sources

    Energy Technology Data Exchange (ETDEWEB)

    Mezei, F. [Eotvos Univ., Budapest (Hungary)]|[Hahn-Meitner Institut, Berlin (Germany)

    1995-12-31

    We will show, that by using an adapted instrumentation concept, the performance of a continuous source can be emulated by one switch on in long pulses for only about 10% of the total time. This 10 fold gain in neutron economy opens up the way for building reactor like sources with an order of magnitude higher flux than the present technological limits. Linac accelerator driven spallation lends itself favorably for the realization of this kind of long pulse sources, which will be complementary to short pulse spallation sources, the same way continuous reactor sources are.

  9. Life cycle assessment of renewable energy sources

    CERN Document Server

    Singh, Anoop; Olsen, Stig Irving

    2013-01-01

    Governments are setting challenging targets to increase the production of energy and transport fuel from sustainable sources. The emphasis is increasingly on renewable sources including wind, solar, geothermal, biomass based biofuel, photovoltaics or energy recovery from waste. What are the environmental consequences of adopting these other sources? How do these various sources compare to each other? Life Cycle Assessment of Renewable Energy Sources tries to answer these questions based on the universally adopted method of Life Cycle Assessment (LCA). This book introduces the concept and impor

  10. Magnesium-aerial primary current source

    Directory of Open Access Journals (Sweden)

    Barba I. N.

    2007-12-01

    Full Text Available Novel metal-air chemical power sources (CPS 3,0-ВМБ-7,5 have been developed. They have an unlimited shelf life and, even after decades of storage, give almost 100% of the designed capacity. These sources are water-activated. An aqueous salt solution is used as an electrolyte. Such sources are designed for single continuous or discontinuous discharge. The paper presents electrochemical reactions at the electrodes during CPS discharge. Comparison of electrical characteristics of the developed power source and various types of "dry cells" has shown that the developed sources have higher energy characteristics.

  11. Ion source based on the cathodic arc

    Science.gov (United States)

    Sanders, David M.; Falabella, Steven

    1994-01-01

    A cylindrically symmetric arc source to produce a ring of ions which leave the surface of the arc target radially and are reflected by electrostatic fields present in the source to a point of use, such as a part to be coated. An array of electrically isolated rings positioned in the source serves the dual purpose of minimizing bouncing of macroparticles and providing electrical insulation to maximize the electric field gradients within the source. The source also includes a series of baffles which function as a filtering or trapping mechanism for any macroparticles.

  12. The prototype of radioactive ion source

    CERN Document Server

    Aleksandrov, A V; Kot, N K; Andrighetto, A; Stroe, L

    2001-01-01

    The design and experimental results of the RIB source prototype are presented.A source will have the container of sup 2 sup 3 sup 5 U compounds heated up to 2200-2500 degree C. Vapors of uranium fission obtained when the ion source is irradiated by the high-energy neutron flux, are then ionized and extracted from the source. In the experiments with the prototype loaded by sup 1 sup 2 C the source working temperature 2700 degree C was reached, the carbon ion current 10 nA was obtained. The total operation time of more than 100 hours with no performance degradation was demonstrated.

  13. XID II: Statistical Cross-Association of ROSAT Bright Source Catalog X-ray Sources with 2MASS Point Source Catalog Near-Infrared Sources

    CERN Document Server

    Haakonsen, Christian Bernt; 10.1088/0067-0049/184/1/138

    2009-01-01

    The 18806 ROSAT All Sky Survey Bright Source Catalog (RASS/BSC) X-ray sources are quantitatively cross-associated with near-infrared (NIR) sources from the Two Micron All Sky Survey Point Source Catalog (2MASS/PSC). An association catalog is presented, listing the most likely counterpart for each RASS/BSC source, the probability Pid that the NIR source and X-ray source are uniquely associated, and the probability Pnoid that none of the 2MASS/PSC sources are associated with the X-ray source. The catalog includes 3853 high quality (Pid>0.98) X-ray--NIR matches, 2280 medium quality (0.98>Pid>0.9) matches, and 4153 low quality (0.9>Pid>0.5) matches. Of the high quality matches, 1418 are associations that are not listed in the SIMBAD database, and for which no high quality match with a USNO-A2 optical source was presented for the RASS/BSC source in previous work. The present work offers a significant number of new associations with RASS/BSC objects that will require optical/NIR spectroscopy for classification. For...

  14. Calorimeter for pulsed energy sources

    Energy Technology Data Exchange (ETDEWEB)

    Pearce, J.W.; Edmonds, P.H.

    1979-01-01

    A common problem in plasma physics experiments is the measurement of the energy deposited on a water-cooled plate by a pulsed energy source. Examples of this are neutral-beam-line defining plate and targets and tokamak water-cooled limiters. One method of measuring this energy is to integrate the product of the temperature rise (..delta..T) and the flow rate (F) of the coolant over the interval between the pulses. The two input parameters ..delta..T and F are derived from a differential thermopile and a turbine flow meter, respectively. A simple digital readout circuit displays the deposited energy in a light-emitting diode display. The circuit uses a commercially available, dual-slope analog-to-digital converter (ADC) in a novel configuration that multiplies ..delta..T and F directly. Calibration of the readout circuit is quick and simple, and short-term accuracies of 5% are easily obtained. Over longer periods the accuracy becomes degraded, primarily by thermal drifts in the thermopile amplifier and in the thermopile connections and the wiring. This offset must be compensated for by a simple adjustment before each experimental run. This readout circuit has been used successfully on the Impurity Study Experiment (ISX-B) neutral beam lines and is most convenient for deposited energy measurements in applications in which computerized data acquisition is not available.

  15. Polymer biocomposites with renewable sources

    Directory of Open Access Journals (Sweden)

    S. Kuciel

    2010-07-01

    Full Text Available Nowadays production of natural biodegradable polymer composites is an important research topic on the stage of renewable sourcesimplementation instead of petrochemical sources. In this work, possibilities of processing biocomposites on the base on different types of biopolymers – polylactide (PLA, thermoplastic starch (TPS, polyhydroxybutyrate (PHB, cellulose acetate (CA - filled with natural fibers such as wood, kenaf, horse hair and nettle are presented. Large variety of natural fibers and their developed surface which increases adhesion to matrix makes them an attractive filler material. The fibers serve as reinforcement by giving strength and stiffness to the structure while the polymer matrix holds the fibers in place so that suitable structural composites can be made. Main physic-mechanical properties of natural fibers and biopolymers are presented. Modulus of elasticity and tensile strength increased with rising content of natural fibers in composite. The results show that biocomposites based on starch or PHB filled with kenaf fibers has the best mechanical properties. Modulus of elasticity achieves 10-12 GPa and tensile strength 50 MPa. This property can be interesting for packaging especially for fresh food like fruits or vegetables and for technical products with short-time life cycles. In future prospects, biocomposites based on biopolymers with a long time of decomposition can be interesting alternative as a construction material in automotive sectors.

  16. Commissioning of SAGA Light Source

    CERN Document Server

    Tomimasu, Takio; Koda, Shigeru; Ohgaki, Hideaki; Takabayashi, Yuichi; Toyokawa, Hiroyuki; Yasumoto, Masato; Yoshida, Katuhide

    2005-01-01

    The SAGA Light Source (SAGA-LS) consists of a 250-MeV electron linac injector and an eight-hold symmetry 1.4-GeV storage ring with eight double-bend (DB) cell and eight 2.93-m long straight sections. The DB cell structure with a distributed dispersion system was chosen to produce a compact ring of 75.6-m long circumference. The machine construction begun September 29, 2003. The ring magnets of steel laminated structure, vacuum chambers made of aluminum alloy, pumping systems and four temperature controlled cooling water systems for the linac accelerating wave guides etc. were installed in March, 2004. The injector, a 500-MHz ring rf damped cavity, rf klystrons, beam transport systems for injection and their controlled systems were installed in July, 2004. The commissioning begun August 25, 2004. A 250-MeV beam was accelerated on September 29. The beam size is 1-mm in diameter and the energy spread is 0.8 % (FWHM). The first revolution of 250-MeV beam around the ring took place October 22. Beam was stored on N...

  17. CMBACT: CMB from ACTive sources

    Science.gov (United States)

    Pogosian, Levon; Vachaspati, Tanmay

    2011-06-01

    This code is based on the cosmic string model described in this paper by Pogosian and Vachaspati, as well as on the CMBFAST code created by Uros Seljak and Matias Zaldarriaga. It contains an integrator for the vector contribution to the CMB temperature and polarization. The code is reconfigured to make it easier to use with or without active sources. To produce inflationary CMB spectra one simply sets the string tension to zero (gmu=0.0d0). For a non-zero value of tension only the string contribution is calculated. An option is added to randomize the directions of velocities of consolidated segments as they evolve in time. In the original segment model, which is still the default version (irandomv=0), each segment is given a random velocity initially, but then continues to move in a straight line for the rest of its life. The new option (irandomv=1) allows to additionally randomize velocities of each segment at roughly each Hubble time. However, the merits of this new option are still under investigation. The default version (irandomv=0) is strongly recommended, since it actually gives reasonable unequal time correlators. For each Fourier mode, k, the string stress-energy components are now evaluated on a time grid sufficiently fine for that k.

  18. Electricity generation by intermittent sources

    Science.gov (United States)

    Wagner, F.

    2015-08-01

    This paper deals with the production of electricity by wind and photovoltaic (PV) power mostly in Germany. The German data of 2012 are scaled to a 100% supply of the electricity consumption by renewable sources. Wind and PV power are mixed in a ratio which minimises back-up energy. The 100%, optimal mix data are used to identify the powers to be installed, the accumulating backup and surplus energies, the size of storage to replace thermal back-up power, the possibilities of demand-side-management, and the specific CO2 production. The benefits of using an EU-wide field of renewable energies (RES) instead of the national one are quantified and the interconnection capacities specified. Finally, the costs of installing RES are discussed. The conclusion is that a 100% supply by RES may not be meaningful. Large-scale supply by RES alone has deficiencies and it will remain a major task for science and technology to either improve such a system or find a suitable replacement.

  19. Electricity generation by intermittent sources

    Directory of Open Access Journals (Sweden)

    Wagner F.

    2015-01-01

    Full Text Available This paper deals with the production of electricity by wind and photovoltaic (PV power mostly in Germany. The German data of 2012 are scaled to a 100% supply of the electricity consumption by renewable sources. Wind and PV power are mixed in a ratio which minimises back-up energy. The 100%, optimal mix data are used to identify the powers to be installed, the accumulating backup and surplus energies, the size of storage to replace thermal back-up power, the possibilities of demand-side-management, and the specific CO2 production. The benefits of using an EU-wide field of renewable energies (RES instead of the national one are quantified and the interconnection capacities specified. Finally, the costs of installing RES are discussed. The conclusion is that a 100% supply by RES may not be meaningful. Large-scale supply by RES alone has deficiencies and it will remain a major task for science and technology to either improve such a system or find a suitable replacement.

  20. Newly graduated nurses' use of knowledge sources

    DEFF Research Database (Denmark)

    Voldbjerg, Siri Lygum; Grønkjaer, Mette; Sørensen, Erik Elgaard;

    2016-01-01

    AIM: To advance evidence on newly graduated nurses' use of knowledge sources. BACKGROUND: Clinical decisions need to be evidence-based and understanding the knowledge sources that newly graduated nurses use will inform both education and practice. Qualitative studies on newly graduated nurses' use...... of knowledge sources are increasing though generated from scattered healthcare contexts. Therefore, a metasynthesis of qualitative research on what knowledge sources new graduates use in decision-making was conducted. DESIGN: Meta-ethnography. DATA SOURCES: Nineteen reports, representing 17 studies, published...... sources during their first 2-year postgraduation were interpreted in the main theme 'self and others as knowledge sources,' with two subthemes 'doing and following' and 'knowing and doing,' each with several elucidating categories. The metasynthesis revealed a line of argument among the report findings...

  1. International workshop on cold neutron sources

    Energy Technology Data Exchange (ETDEWEB)

    Russell, G.J.; West, C.D. (comps.) (Los Alamos National Lab., NM (United States))

    1991-08-01

    The first meeting devoted to cold neutron sources was held at the Los Alamos National Laboratory on March 5--8, 1990. Cosponsored by Los Alamos and Oak Ridge National Laboratories, the meeting was organized as an International Workshop on Cold Neutron Sources and brought together experts in the field of cold-neutron-source design for reactors and spallation sources. Eighty-four people from seven countries attended. Because the meeting was the first of its kind in over forty years, much time was spent acquainting participants with past and planned activities at reactor and spallation facilities worldwide. As a result, the meeting had more of a conference flavor than one of a workshop. The general topics covered at the workshop included: Criteria for cold source design; neutronic predictions and performance; energy deposition and removal; engineering design, fabrication, and operation; material properties; radiation damage; instrumentation; safety; existing cold sources; and future cold sources.

  2. The Commercial Open Source Business Model

    Science.gov (United States)

    Riehle, Dirk

    Commercial open source software projects are open source software projects that are owned by a single firm that derives a direct and significant revenue stream from the software. Commercial open source at first glance represents an economic paradox: How can a firm earn money if it is making its product available for free as open source? This paper presents the core properties of com mercial open source business models and discusses how they work. Using a commercial open source approach, firms can get to market faster with a superior product at lower cost than possible for traditional competitors. The paper shows how these benefits accrue from an engaged and self-supporting user community. Lacking any prior comprehensive reference, this paper is based on an analysis of public statements by practitioners of commercial open source. It forges the various anecdotes into a coherent description of revenue generation strategies and relevant business functions.

  3. Detecting Diffuse Sources in Astronomical Images

    CERN Document Server

    Butler-Yeoman, T; Hollitt, C P; Hogg, D W; Johnston-Hollitt, M

    2016-01-01

    We present an algorithm capable of detecting diffuse, dim sources of any size in an astronomical image. These sources often defeat traditional methods for source finding, which expand regions around points of high intensity. Extended sources often have no bright points and are only detectable when viewed as a whole, so a more sophisticated approach is required. Our algorithm operates at all scales simultaneously by considering a tree of nested candidate bounding boxes, and inverts a hierarchical Bayesian generative model to obtain the probability of sources existing at given locations and sizes. This model naturally accommodates the detection of nested sources, and no prior knowledge of the distribution of a source, or even the background, is required. The algorithm scales nearly linear with the number of pixels making it feasible to run on large images, and requires minimal parameter tweaking to be effective. We demonstrate the algorithm on several types of astronomical and artificial images.

  4. Approaching Source Illiteracy, or How a Source Is Like a Frog

    Science.gov (United States)

    Murphy, Nora G.

    2016-01-01

    Just as fluency isn't knowing every word in a language, source literacy isn't knowing every source. It is, instead, the ability to interpret from context, to know what to ask, to read the clues, and to use the understanding brought from knowing about other sources. A person fluent in source literacy is able to do this automatically, the way you…

  5. Amateur Sources Breaking the News, Meta Sources Authorizing the News of Gaddafi's Death

    DEFF Research Database (Denmark)

    Mortensen, Mette; Kristensen, Nete Nørgaard

    2013-01-01

    of interplay between elite and non-elite sources as well as media professionals and amateur sources. On account of their proximity to unfolding events, amateur sources often break the news by means of raw and fragmented bits of visual and verbal information. Elite sources rarely possess the same exclusive...

  6. The First Sources of Light

    Science.gov (United States)

    Loeb, Avi

    2011-09-01

    Looking deep into the Universe through powerful telescopes, we can see images of the Universe when it was younger because of the finite time it takes light to travel to us from distant sources. Existing data sets include an image of the Universe when it was 0.4 million years old (in the form of the cosmic microwave background), as well as images of individual galaxies when the Universe was older than a billion years. But there is a serious challenge: in between these two epochs was a period when the Universe was dark, stars had not yet formed, and the cosmic microwave background no longer traced the distribution of matter. And this is precisely the most interesting period, when the primordial soup evolved into the rich zoo of objects we now see. The observers are moving ahead along several fronts. The first involves the construction of large infrared telescopes on the ground and in space, that will provide us with new photos of the first galaxies. Current plans include ground-based telescopes which are 24-42 meter in diameter, and NASA's successor to the Hubble Space Telescope, called the James Webb Space Telescope. In addition, several observational groups around the globe are constructing radio arrays that will be capable of mapping the three-dimensional distribution of cosmic hydrogen in the infant Universe. These arrays are aiming to detect the long-wavelength (redshifted 21-cm) radio emission from hydrogen atoms. The images from these antenna arrays will reveal how the non-uniform distribution of neutral hydrogen evolved with cosmic time and eventually was extinguished by the ultra-violet radiation from the first galaxies. Theoretical research has focused in recent years on predicting the expected signals for the above instruments and motivating these ambitious observational projects.

  7. The Frankfurt neutron source FRANZ

    Science.gov (United States)

    Alzubaidi, Suha; Bartz, Ulrich; Basten, Markus; Bechtold, Alexander; Chau, Long Phi; Claessens, Christine; Dinter, Hannes; Droba, Martin; Fix, Christopher; Hähnel, Hendrik; Heilmann, Manuel; Hinrichs, Ole; Huneck, Simon; Klump, Batu; Lotz, Marcel; Mäder, Dominik; Meusel, Oliver; Noll, Daniel; Nowottnick, Tobias; Obermayer, Marcus; Payir, Onur; Petry, Nils; Podlech, Holger; Ratzinger, Ulrich; Schempp, Alwin; Schmidt, Stefan; Schneider, Philipp; Seibel, Anja; Schwarz, Malte; Schweizer, Waldemar; Volk, Klaus; Wagner, Christopher; Wiesner, Christoph

    2016-05-01

    A 2MeV proton beam will produce a quasi-Maxwellian neutron spectrum of around 30 keV by the 7Li(p, n)7Be reaction. The experiments are mainly focused on the measurement of differential neutron capture cross sections relevant for the astrophysical s-process in nuclear synthesis. Moreover, proton capture cross sections for the astrophysical p-process can be measured directly with the proton beam. For an efficient time of flight measurement of the neutron energies along the 0.7 m long drift from the Li-target to the sample, 1ns short, intense proton pulses are needed at the target. Additionally, to reach 107 n/cm2/s at the sample, a pulse repetition rate of 250 kHz is intended. After completion and successful running in, FRANZ will become a user facility with internal and external users. The 120 kV injector terminal and the 200mA proton source as well as the low-energy beam transport section and the FRANZ cave have been realized successfully. The 1.9 MV RF accelerator consists of a combined 4-Rod-RFQ/IH-DTL-resonator and is in the RF tuning and power testing phase. The 2 MeV transport and rebuncher section is ready for installation. In a first step FRANZ will offer experimental areas for neutron activation experiments and for proton beam experiments, as mentioned above. From the accelerator physics point of view, FRANZ will be an excellent facility for high current beam investigations and for beam wall interaction studies.

  8. Radiologic inspection in an office built rod contaminated with radioactive material, in Tiaquepaque, Jalisco, Mexico; Inspeccion radiologica en una oficina construida con varilla contaminada con material radiactivo, en Tlaquepaque, Jalisco, Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Salas Mar, B.

    2011-07-01

    Note that in 1983 took place {sup T}he most important radiological accident occurred in Mexico in recent years occurred in Ciudad Juarez, Chihuahua, consisting ea involuntary casting a source of Cobalt-60 (originally intended for medical use in teletherapy) and manufacture of rods for the construction and steel bases for tables, in the smelter {sup S}teel de Chihuahua{sup ,} so presumably, that the rods of the office of Tlaquepaque, come from the radiological accident.

  9. The source issue in infrared microspectroscopy

    CERN Document Server

    Smith, T I

    2002-01-01

    Infrared spectroscopy using a Fourier Transform Infrared (FTIR) spectrometer is routine. These instruments are sophisticated and mature, and generally use a blackbody radiator as their infrared source. However, because the brightness of a thermal source is limited, the signal-to-noise ratio of these instruments begins to degrade at spatial resolutions not much better than 1 mm and they are rarely useful at resolutions smaller than 20 mu m. Synchrotrons provide much brighter infrared beams than thermal sources, and Free-Electron Lasers (FELs) provide even brighter beams than synchrotrons. We will discuss the limitations of thermal sources, and show that a synchrotron is an excellent source for infrared spectroscopy at spatial resolutions on the order of the wavelength (lambda). Even better spatial resolution, about lambda/10, can be expected if an FEL is used as a source.

  10. A compact, coherent light source system architecture

    Science.gov (United States)

    Biedron, S. G.; Dattoli, G.; DiPalma, E.; Einstein, J.; Milton, S. V.; Petrillo, V.; Rau, J. V.; Sabia, E.; Spassovsky, I. P.; van der Slot, P. J. M.

    2016-09-01

    Our team has been examining several architectures for short-wavelength, coherent light sources. We are presently exploring the use and role of advanced, high-peak power lasers for both accelerating the electrons and generating a compact light source with the same laser. Our overall goal is to devise light sources that are more accessible by industry and in smaller laboratory settings. Although we cannot and do not want to compete directly with sources such as third-generation light sources or that of national-laboratory-based free-electron lasers, we have several interesting schemes that could bring useful and more coherent, short-wavelength light source to more researchers. Here, we present and discuss several results of recent simulations and our future steps for such dissemination.

  11. Micro-source development for XMASS experiment

    Energy Technology Data Exchange (ETDEWEB)

    Kim, N.Y., E-mail: nykim@ibs.re.kr [Korea Research Institute of Standards and Science, Daejeon 305-340 (Korea, Republic of); Department of Physics, Sejong University, Seoul 143-747 (Korea, Republic of); Abe, K. [Kamioka Observatory, Institute for Cosmic Ray Research, The University of Tokyo, Higashi-Mozumi, Kamioka, Hida, Gifu 506-1205 (Japan); Kavli Institute for the Physics and Mathematics of the Universe (WPI), The University of Tokyo, Kashiwa, Chiba 277-8582 (Japan); Hieda, K. [Kamioka Observatory, Institute for Cosmic Ray Research, The University of Tokyo, Higashi-Mozumi, Kamioka, Hida, Gifu 506-1205 (Japan); Hiraide, K. [Kamioka Observatory, Institute for Cosmic Ray Research, The University of Tokyo, Higashi-Mozumi, Kamioka, Hida, Gifu 506-1205 (Japan); Kavli Institute for the Physics and Mathematics of the Universe (WPI), The University of Tokyo, Kashiwa, Chiba 277-8582 (Japan); Hirano, S. [Kamioka Observatory, Institute for Cosmic Ray Research, The University of Tokyo, Higashi-Mozumi, Kamioka, Hida, Gifu 506-1205 (Japan); Kishimoto, Y.; Kobayashi, K.; Moriyama, S. [Kamioka Observatory, Institute for Cosmic Ray Research, The University of Tokyo, Higashi-Mozumi, Kamioka, Hida, Gifu 506-1205 (Japan); Kavli Institute for the Physics and Mathematics of the Universe (WPI), The University of Tokyo, Kashiwa, Chiba 277-8582 (Japan); Nakagawa, K. [Kamioka Observatory, Institute for Cosmic Ray Research, The University of Tokyo, Higashi-Mozumi, Kamioka, Hida, Gifu 506-1205 (Japan); Nakahata, M. [Kamioka Observatory, Institute for Cosmic Ray Research, The University of Tokyo, Higashi-Mozumi, Kamioka, Hida, Gifu 506-1205 (Japan); Kavli Institute for the Physics and Mathematics of the Universe (WPI), The University of Tokyo, Kashiwa, Chiba 277-8582 (Japan); Nishiie, H. [Kamioka Observatory, Institute for Cosmic Ray Research, The University of Tokyo, Higashi-Mozumi, Kamioka, Hida, Gifu 506-1205 (Japan); and others

    2015-06-01

    XMASS is a multipurpose liquid-xenon detector that currently aims to directly detect dark matter. In this paper, we describe the fabrication and characterization of reference sources used for the energy calibration and position reconstruction of the present XMASS detector. Several gamma-ray sources were produced in the form of a sealed needle-source. A thin-wall tube with a diameter of approximately 0.2 mm was sealed at both ends, with the {sup 241}Am or {sup 57}Co source material contained inside. The active region of the source was observed to be 1–2 mm long, close to the tip of the needle. These sources were tested in the XMASS detector, and the results were compared with Monte-Carlo simulations.

  12. Round-robin multiple-source localization.

    Science.gov (United States)

    Mantzel, William; Romberg, Justin; Sabra, Karim G

    2014-01-01

    This paper introduces a round-robin approach for multi-source localization based on matched-field processing. Each new source location is estimated from the ambiguity function after nulling from the data vector the current source location estimates using a robust projection matrix. This projection matrix effectively minimizes mean-square energy near current source location estimates subject to a rank constraint that prevents excessive interference with sources outside of these neighborhoods. Numerical simulations are presented for multiple sources transmitting through a fixed (and presumed known) generic Pekeris ocean waveguide in the single-frequency and broadband-coherent cases that illustrate the performance of the proposed approach which compares favorably against other previously published approaches. Furthermore, the efficacy with which randomized back-propagations may also be incorporated for computational advantage is also presented.

  13. Phenomena of Open Source and Slovenia's Adaption

    Directory of Open Access Journals (Sweden)

    Matej Mertik

    2011-06-01

    Full Text Available Although free open source libre (FLOSS software is increasing its presence in the media and in debates between IT professionals, and although even citizens in general are starting to talk about it, FLOSS is still in general quite an unknown quantity. But this is changing. There is more and more interest in open source software by general users and also its influence on the public and business sector is undeniable. What is open source? Where did it all start? How is Slovenia using open source? What have we learned? Where are the opportunities for FLOSS? These are the sort of questions we will try to answer in this document. Slovenia implemented some of the important steps in introducing open source, however we are still far behind in terms of open source adoption and great opportunities exist for its better use in future.

  14. H- ion source developments at the SNS

    Energy Technology Data Exchange (ETDEWEB)

    Welton, Robert F [ORNL; Stockli, Martin P [ORNL; Murray Jr, S N [ORNL; Pennisi, Terry R [ORNL; Han, Baoxi [ORNL; Kang, Yoon W [ORNL; Goulding, Richard Howell [ORNL; Crisp, Danny W [ORNL; Sparks, Dennis O [ORNL; Luciano, Nicholas P [ORNL; Carmichael, Justin R [ORNL; Carr, Jr, Jerry [ORNL

    2008-01-01

    The U.S. Spallation Neutron Source (SNS) will require substantially higher average and pulse H- beam currents than can be produced from conventional ion sources such as the base line SNS source. H- currents of 40-50 mA (SNS operations) and 70-100 mA (power upgrade project) with an rms emittance of 0.20-0.35 Pi mm mrad and a ~7% duty factor will be needed. We are therefore investigating several advanced ion source concepts based on RF excitation. First, the performance characteristics of an external antenna source based on an Al2O3 plasma chamber combined with an external multicusp magnetic configuration, an elemental Cs system, and plasma gun will be discussed. Second, the first plasma measurements of a helicon-driven H- ion source will also be presented.

  15. A Plasma Ion Source for ISOLTRAP

    CERN Document Server

    Skov, Thomas Guldager

    2016-01-01

    In this report, my work testing the new Penning ion source as a summer student at ISOLTRAP is described. The project was composed of three stages: (1) Setting up a test laboratory in building 275, (2) characterizing the ion source, and (3) implementing and testing the source in the ISOLTRAP setup. After setting up the test laboratory, the ion source was tested in a constant pressure environment with produced ion currents in the range of nA . An extensive scan of the source ion current versus operating parameters (pressure, voltage) was performed. A setup with pulsed gas flow was also tested, allowing a reduction of the gas load on the vacuum system. The behavior of the ion source together with the ISOLTRAP setup was also investigated, allowing to understand current limitations and future directions of improvement.

  16. Contribution to Asterisk Open Source Project

    OpenAIRE

    González Martín, Sergio

    2009-01-01

    With this final master thesis we are going to contribute to the Asterisk open source project. Asterisk is an open source project that started with the main objective of develop an IP telephony platform, completely based on Software (so not hardware dependent) and under an open license like GPL. This project was started on 1999 by the software engineer Mark Spencer at Digium. The main motivation of that open source project was that the telecommunications sector is lack of open solutions, and m...

  17. Blind source separation dependent component analysis

    CERN Document Server

    Xiang, Yong; Yang, Zuyuan

    2015-01-01

    This book provides readers a complete and self-contained set of knowledge about dependent source separation, including the latest development in this field. The book gives an overview on blind source separation where three promising blind separation techniques that can tackle mutually correlated sources are presented. The book further focuses on the non-negativity based methods, the time-frequency analysis based methods, and the pre-coding based methods, respectively.

  18. HTGR Mechanistic Source Terms White Paper

    Energy Technology Data Exchange (ETDEWEB)

    Wayne Moe

    2010-07-01

    The primary purposes of this white paper are: (1) to describe the proposed approach for developing event specific mechanistic source terms for HTGR design and licensing, (2) to describe the technology development programs required to validate the design methods used to predict these mechanistic source terms and (3) to obtain agreement from the NRC that, subject to appropriate validation through the technology development program, the approach for developing event specific mechanistic source terms is acceptable

  19. Free for All: Open Source Software

    Science.gov (United States)

    Schneider, Karen

    2008-01-01

    Open source software has become a catchword in libraryland. Yet many remain unclear about open source's benefits--or even what it is. So what is open source software (OSS)? It's software that is free in every sense of the word: free to download, free to use, and free to view or modify. Most OSS is distributed on the Web and one doesn't need to…

  20. Open source innovation phenomenon, participant behaviour, impact

    CERN Document Server

    Herstatt, Cornelius

    2015-01-01

    Open Source Innovation (OSI) has gained considerable momentum within the last years. Academic and management practice interest grows as more and more end-users consider and even participate in Open Source product development like Linux, Android, or Wikipedia. Open Source Innovation: Phenomenon, Participant Behaviour, Impact brings together rigorous academic research and business importance in scrutinizing OCI from three perspectives: The Phenomenon, Participants' Behavior, and Business Implications. The first section introduces OCI artefacts, including who is participating and why, and provide