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Sample records for external exposure model

  1. The modelling of external exposure and inhalation pathways in COSYMA

    International Nuclear Information System (INIS)

    Brown, J.; Simmonds, JR.; Ehrhardt, J.; Hasemann, I.

    1991-01-01

    Following an accidental release of radionuclides to atmosphere the major direct exposure pathways of concern are: external irradiation from material in the cloud; internal exposure following inhalation of material in the cloud; external irradiation from material deposited on the ground; and external irradiation due to contamination of skin and clothes. In addition material resuspended from the ground can be inhaled and lead to internal exposure. In this paper the way that these exposure pathways are modelled in COSYMA is described. At present in COSYMA external exposure from deposited material is modelled using a dataset of doses per unit deposit of various radionuclides. This dataset, is based on activity deposited on undisturbed soil. The basic data are for doses outdoors and shielding factors are used to estimate doses for people indoors. Various groups of people spending different amounts of time indoors and out can be considered and shielding factors appropriate to three building types can be adopted. A more complex model has also been developed to predict radiation exposure following deposition to different surfaces in the environment. This model called EXPURT is briefly described in this paper. Using EXPURT, doses as a function of time after a single deposit have been calculated for people living in three types of area. These results are described in the paper and compared with those that are currently used in COSYMA. The paper will also discuss what future work is required in this area and the adequacy of existing models

  2. External exposure model for various geometries of contaminated materials

    International Nuclear Information System (INIS)

    LePoire, D.; Kamboj, S.; Yu, C.

    1996-01-01

    A computational model for external exposure was developed for the U.S. Department of Energy's residual radioactive material guideline computer code (RESRAD) on the basis of dose coefficients from Federal Guidance Report No. 12 and the point-kernel method. This model includes the effects of different materials and exposure distances, as well as source geometry (cover thickness, source depth, area, and shape). A material factor is calculated on the basis of the point-kernel method using material-specific photon cross-section data and buildup factors. This present model was incorporated into RESRAD-RECYCLE (a RESRAD family code used for computing radiological impacts of metal recycling) and is being incorporated into RESRAD-BUILD (a DOE recommended code for computing impacts of building decontamination). The model was compared with calculations performed with the Monte Carlo N-Particle Code (MCNP) and the Microshield code for three different source geometries, three different radionuclides ( 234 U, 238 U, and 60 Co, representing low, medium, and high energy, respectively), and five different source materials (iron, copper, aluminum, water, and soil). The comparison shows that results of this model are in very good agreement with MCNP calculations (within 5% for 60 Co and within 30% for 238 U and 234 U for all materials and source geometries). Significant differences (greater than 100%) were observed with Microshield for thin 234 U sources

  3. An Exploratory Study: Assessment of Modeled Dioxin Exposure in Ceramic Art Studios (External Review Draft)

    Science.gov (United States)

    EPA has released an external review draft entitled, An Exploratory Study: Assessment of Modeled Dioxin Exposure in Ceramic Art Studios(External Review Draft). The public comment period and the external peer-review workshop are separate processes that provide opportunities ...

  4. SOILD: A computer model for calculating the effective dose equivalent from external exposure to distributed gamma sources in soil

    International Nuclear Information System (INIS)

    Chen, S.Y.; LePoire, D.; Yu, C.; Schafetz, S.; Mehta, P.

    1991-01-01

    The SOLID computer model was developed for calculating the effective dose equivalent from external exposure to distributed gamma sources in soil. It is designed to assess external doses under various exposure scenarios that may be encountered in environmental restoration programs. The models four major functional features address (1) dose versus source depth in soil, (2) shielding of clean cover soil, (3) area of contamination, and (4) nonuniform distribution of sources. The model is also capable of adjusting doses when there are variations in soil densities for both source and cover soils. The model is supported by a data base of approximately 500 radionuclides. 4 refs

  5. Control of external radiation exposure

    International Nuclear Information System (INIS)

    Abd Nasir Ibrahim; Azali Muhammad; Ab Razak Hamzah; Abd Aziz Mohamed; Mohammad Pauzi Ismail

    2004-01-01

    The following subjects are discussed - Control of external radiation exposure: working time, working distance, shielding: Total Linear Attenuation Coefficient, Half-Value Layer (HVL), Tenth-Value Layer (TVL); Build-up Factor

  6. Model of external exposure of population living in the areas subjected to radioactive contamination

    International Nuclear Information System (INIS)

    Golikov, V.Yu.; Balonov, M.I.

    2002-01-01

    In the paper, we formulated the general approach to assessment of external doses to population living in contaminated areas (the model equation and the set of parameters). The model parameters were assessed on the basis of results of monitoring in the environment, phantom experiments, and social and demographic information obtained on the contaminated areas. Verification of model assessments performed by comparison with measurement results of individual external doses in inhabitants within the thermoluminescent dosimetry method have shown that differences in dose assessments within both methods does not exceed 1.5 times at a confidence level of 95%. In the paper, we present the results illustrating specific features of external dose formation in population living in the areas of Russia subjected to radioactive contamination due to nuclear tests at the Semipalatinsk test site, radioactive releases from the Mayak enterprise, and the Chernobyl accident. (author)

  7. Tomographic anthropomorphic models. Pt. 4. Organ doses for adults due to idealized external photon exposures

    CERN Document Server

    Zankl, M; Petoussi-Henss, N; Regulla, D

    2002-01-01

    The present report contains extensive tables and figures of conversion coefficients of organ and tissue equivalent dose, normalised to air kerma free in air for voxel anthropomorphic phantoms and for standard geometries of external photon radiation, estimated with Monte Carlo techniques. Four realistic adult voxel phantoms were used for the calculations, based on computed tomographic data of real people: three male phantoms, two of them being of average size, one representing a big man, and one female phantom of a tall and somewhat over weighted woman.

  8. Tomographic anthropomorphic models. Pt. 4. Organ doses for adults due to idealized external photon exposures

    International Nuclear Information System (INIS)

    Zankl, M.; Petoussi-Henss, N.; Fill, U.; Regulla, D.

    2002-01-01

    The present report contains extensive tables and figures of conversion coefficients of organ and tissue equivalent dose, normalised to air kerma free in air for voxel anthropomorphic phantoms and for standard geometries of external photon radiation, estimated with Monte Carlo techniques. Four realistic adult voxel phantoms were used for the calculations, based on computed tomographic data of real people: three male phantoms, two of them being of average size, one representing a big man, and one female phantom of a tall and somewhat over weighted woman. (orig.)

  9. AIRGAMMA, External Gamma-Ray Exposure from Radioactive Cloud

    International Nuclear Information System (INIS)

    Hidaka, Akihide; Iijima, Tshinori

    1989-01-01

    1 - Description of program or function: AIRGAMMA calculates quickly the external exposure to gamma rays from a radioactive cloud. 2 - Method of solution: The external exposure is calculated by interpolating the normalized doses providing on the basis of the Gaussian plume model. 3 - Restrictions on the complexity of the problem: Memory requirement is 30 Kbytes

  10. Modelling the external radiation exposure from the Chernobyl fallout using data from the Swedish municipality measurement system.

    Science.gov (United States)

    Jönsson, Mattias; Tondel, Martin; Isaksson, Mats; Finck, Robert; Wålinder, Robert; Mamour, Afrah; Rääf, Christopher

    2017-11-01

    In connection with the Chernobyl fallout and the subsequent deposition of radionuclides in Sweden, Swedish municipalities launched a measurement program to monitor the external radiation exposure. This program encompasses measurements of the ambient dose equivalent rate 1 m above ground at selected locations, and repeats those measurements at the same locations at 7-month intervals. Measurement data compiled from the seven locations with the highest deposition were combined with data from aerial surveys since May 1986 of ground deposition of 137 Cs, high-resolution gamma spectrometry performed at four locations in May 1986, and measurements from fixed continuous air gamma rate monitoring stations from 28 April to 15 May 1986. Based on these datasets, a model of the time pattern of the external dose rate in terms of ambient dose equivalent rate from the Chernobyl fallout was developed. The decrease in the ambient dose equivalent rate could, on average, be described by a four-component exponential decay function with effective half-times of 6.8 ± 0.3 d, 104 ± 26 d, 1.0 ± 0.02 y and 5.5 ± 0.09 y, respectively. The predominant contributions to the external dose rate in the first month were from short-lived fission products superseded by 134 Cs and then 137 Cs. Integrated over 70 y and using extrapolation of the curve fits, our model predicts that 137 Cs contributes about 60% and 134 Cs contributes about 30% of the external effective dose at these seven locations. The projected time-integrated 70 y external effective dose to an unshielded person from all nuclides per unit total activity deposition of 137 Cs is estimated to be 0.29 ± 0.0.08 mSv/(kBq m -2 ). These results are in agreement with those found in Chernobyl contaminated Russian forest areas, and emphasize the usefulness of maintaining a long-term and regular measurement program in contaminated areas. Copyright © 2017 Elsevier Ltd. All rights reserved.

  11. Incorporation of additional radionuclides and the external exposure pathway into the BECAMP [Basic Environmental Compliance and Monitoring Program] radiological assessment model

    International Nuclear Information System (INIS)

    Ng, Yook C.; Rodean, H.C.; Anspaugh, L.R.

    1988-11-01

    The Nevada Applied Ecology Group (NAEG) Model of transport and dose for transuranic radionuclides was modified and expanded for the analysis of radionuclides other than pure alpha-emitters. Doses from internal and external exposures were estimated for the inventories and soil distributions of the individual radionuclides quantified in Areas 2 and 4 of the Nevada Test Site (NTS). We found that the dose equivalents via inhalation to liver, lungs, bone marrow, and bone surface from the plutonium isotopes and 241 Am, those via ingestion to bone marrow and bone surfaces from 90 Sr, and those via ingestion to all the target organs from 137 Cs were the highest from internal exposures. The effective dose equivalents from 137 Cs, 152 Eu, and 154 Eu were the highest from the external exposures. The 60 Co, 152 Eu, 154 Eu, and 155 Eu dose estimates for external exposures greatly exceeded those for internal exposures. The 60 Co, 90 Sr, and 137 Cs dose equivalents from internal exposures were underestimated due to the adoption of some of the foodchain parameter values originally selected for 239 Pu. Nonetheless, the ingestion pathway contributed significantly to the dose estimates for 90 Sr and 137 Cs, but contributed very much less than external exposures to the dose estimates for 60 Co. Therefore, the use of more appropriate values would not alter the identification of important radionuclides, pathways, target organs, and exposure modes in this analysis. 19 refs., 13 figs., 12 tabs

  12. Modeling for Dose Rate Calculation of the External Exposure to Gamma Emitters in Soil

    International Nuclear Information System (INIS)

    Allam, K. A.; El-Mongy, S. A.; El-Tahawy, M. S.; Mohsen, M. A.

    2004-01-01

    Based on the model proposed and developed in Ph.D thesis of the first author of this work, the dose rate conversion factors (absorbed dose rate in air per specific activity of soil in nGy.hr - 1 per Bq.kg - 1) are calculated 1 m above the ground for photon emitters of natural radionuclides uniformly distributed in the soil. This new and simple dose rate calculation software was used for calculation of the dose rate in air 1 m above the ground. Then the results were compared with those obtained by five different groups. Although the developed model is extremely simple, the obtained results of calculations, based on this model, show excellent agreement with those obtained by the above-mentioned models specially that one adopted by UNSCEAR. (authors)

  13. External radiation exposure of the public

    International Nuclear Information System (INIS)

    Mehl, J.

    1977-01-01

    Results of several ten thousand measurements on external radiation (outside buildings, in living rooms) are used for illustrating by isodose charts covering the total area of the Federal Republic of Germany the exposure of the public from external radiation originating from natural radiation of the environment. Results of calculations on external radiation exposure of the public due to releases of radioactivity in air from nuclear installations are used for illustrating by coloured isodose charts the exposure of the public in the plant site vicinity. From comparison of the exposure levels it becomes obvious that if exposure levels of several 10 mrem per year are considered to be of real concern to public health, control of natural radoactivity in the environment of man would require more attention than present and foreseeable releases of radioactivity in air from nuclear inst

  14. Stochastic Control - External Models

    DEFF Research Database (Denmark)

    Poulsen, Niels Kjølstad

    2005-01-01

    This note is devoted to control of stochastic systems described in discrete time. We are concerned with external descriptions or transfer function model, where we have a dynamic model for the input output relation only (i.e.. no direct internal information). The methods are based on LTI systems...

  15. External exposure measurements at Bikini Atoll

    International Nuclear Information System (INIS)

    Greenhouse, N.A.; Miltenberger, R.P.; Lessard, E.T.

    1979-01-01

    External exposure rate surveys from 1975 to 1977 on the islands Nam, Eneu and Bikini of Bikini Atoll gave average external exposure rates of 24, 5.7, and 32 μR/hr respectively. The exposure rate on Eneu Island is uniform, whereas those on Bikini and Nam range from 7.0 to 80. μR/hr. Based on an assumed living pattern at Bikini Island, the adult male Bikinian is estimated to be in the presence of an external radiation field corresponding to 16 μR/hr due to debris and fallout from the 1954 BRAVO incident. This corresponds to a 30 year dose equivalent of 2.8 rem

  16. Historical estimates of external gamma exposure and collective external gamma exposure from testing at the Nevada Test Site. I. Test series through HARDTACK II, 1958

    Energy Technology Data Exchange (ETDEWEB)

    Anspaugh, L.R.; Church, B.W.

    1985-12-01

    In 1959, the Test Manager's Committee to Establish Fallout Doses calculated estimated external gamma exposure at populated locations based upon measurements of external gamma-exposure rate. Using these calculations and estimates of population, we have tabulated the collective estimated external gamma exposures for communities within established fallout patterns. The total collective estimated external gamma exposure is 85,000 person-R. The greatest collective exposures occurred in three general areas: Saint George, Utah; Ely, Nevada; and Las Vegas, Nevada. Three events, HARRY (May 19, 1953), BEE (March 22, 1955), and SMOKY (August 31, 1957), accounted for over half of the total collective estimated external gamma exposure. The bases of the calculational models for external gamma exposure of ''infinite exposure,'' ''estimated exposure,'' and ''one year effective biological exposure'' are explained. 4 figs., 7 tabs.

  17. Historical estimates of external gamma exposure and collective external gamma exposure from testing at the Nevada Test Site. I. Test series through HARDTACK II, 1958

    International Nuclear Information System (INIS)

    Anspaugh, L.R.; Church, B.W.

    1986-01-01

    In 1959, the Test Manager's Committee to Establish Fallout Doses calculated estimated external gamma exposure at populated locations based upon measurements of external gamma-exposure rate. Using these calculations and estimates of population, we have tabulated the collective estimated external gamma exposures for communities within established fallout patterns. The total collective estimated external gamma exposure is 85,000 person-R. The greatest collective exposures occurred in three general areas: Saint George, UT; Ely, NV; and Las Vegas, NV. Three events, HARRY (19 May 1953), BEE (22 March 1955), and SMOKY (31 August 1957), accounted for more than half the total collective estimated external gamma exposure. The bases of the calculational models for external gamma exposure of infinite exposure, estimated exposure, and 1-yr effective biological exposure are explained

  18. Historical estimates of external gamma exposure and collective external gamma exposure from testing at the Nevada Test Site. I. Test series through HARDTACK II, 1958

    International Nuclear Information System (INIS)

    Anspaugh, L.R.; Church, B.W.

    1985-12-01

    In 1959, the Test Manager's Committee to Establish Fallout Doses calculated estimated external gamma exposure at populated locations based upon measurements of external gamma-exposure rate. Using these calculations and estimates of population, we have tabulated the collective estimated external gamma exposures for communities within established fallout patterns. The total collective estimated external gamma exposure is 85,000 person-R. The greatest collective exposures occurred in three general areas: Saint George, Utah; Ely, Nevada; and Las Vegas, Nevada. Three events, HARRY (May 19, 1953), BEE (March 22, 1955), and SMOKY (August 31, 1957), accounted for over half of the total collective estimated external gamma exposure. The bases of the calculational models for external gamma exposure of ''infinite exposure,'' ''estimated exposure,'' and ''one year effective biological exposure'' are explained. 4 figs., 7 tabs

  19. Development of a external exposure computational model for studying of input dose in skin for radiographs of thorax and vertebral column

    International Nuclear Information System (INIS)

    Muniz, Bianca C.; Menezes, Claudio J.M.; Vieira, Jose W.

    2014-01-01

    The dosimetric measurements do not always happen directly in the human body. Therefore, these assessments can be performed using anthropomorphic models (phantoms) evidencing models computational exposure (MCE) using techniques of Monte Carlo Method for virtual simulations. These processing techniques coupled with more powerful and affordable computers make the Monte Carlo method one of the tools most used worldwide in radiation transport area. In this work, the Monte Carlo EGS4 program was used to develop a computer model of external exposure to study the entrance skin dose for chest and column X-radiography and, aiming to optimize these practices by reducing doses to patients, professionals involved and the general public. The results obtained experimentally with the electrometer Radcal, model 9015, associated with the ionization chamber for radiology model 10X5-6, showed that the proposed computational model can be used in quality assurance programs in radiodiagnostic, evaluating the entrance skin dose when varying parameters of the radiation beam such as kilo voltage peak (kVp), current-time product (mAs), total filtration and distance surface source (DFS), optimizing the practices in radiodiagnostic and meeting the current regulation

  20. Report on emergency exposure to external radiation

    International Nuclear Information System (INIS)

    Pochin, E.E.; Rock Carling, Ernest; Court Brown, W.M.

    1960-01-01

    The Medical Research Council has continued a study of the effects on the health of persons in the neighbourhood of atomic energy installations should there be a release of radioactive material as a result of fires or other incidents. The Council's Committee on Protection against Ionizing Radiations has already reported (Medical Research Council, 1959) on the maximum permissible dietary contamination for iodine 131, strontium 89, strontium 90 and caesium. 137, since it was considered that for the members of the public normally resident in the area affected ingestion of contaminated food would generally be the limiting source of hazard after any such accident and that intake by inhalation, or radiation from the exterior, would become of importance only in rather special circumstances The present report deals with the problem of exposure from the exterior, namely, from external sources of beta and gamma radiation. This exposure might be derived from two sources, one of relatively short duration from the passage of a cloud of radioactive material, the other of longer duration from deposited material

  1. Report on emergency exposure to external radiation

    Energy Technology Data Exchange (ETDEWEB)

    Pochin, E E; Rock Carling, Ernest; Court Brown, W M [Medical Research Council, Committee on Protection against Ionizing Radiations, London (United Kingdom); and others

    1960-12-01

    The Medical Research Council has continued a study of the effects on the health of persons in the neighbourhood of atomic energy installations should there be a release of radioactive material as a result of fires or other incidents. The Council's Committee on Protection against Ionizing Radiations has already reported (Medical Research Council, 1959) on the maximum permissible dietary contamination for iodine 131, strontium 89, strontium 90 and caesium. 137, since it was considered that for the members of the public normally resident in the area affected ingestion of contaminated food would generally be the limiting source of hazard after any such accident and that intake by inhalation, or radiation from the exterior, would become of importance only in rather special circumstances The present report deals with the problem of exposure from the exterior, namely, from external sources of beta and gamma radiation. This exposure might be derived from two sources, one of relatively short duration from the passage of a cloud of radioactive material, the other of longer duration from deposited material.

  2. Distribution of external exposures in the Russian population after the Chernobyl accident

    International Nuclear Information System (INIS)

    Balonov, M.I.; Golikov, V.Yu.; Erkin, V.G.; Ponomarev, A.V.

    2000-01-01

    The data of the monitoring of external exposure in the population of the Chernobyl accident area in Russia during seven years are presented. The deterministic model has been developed for estimation of the average dose of external exposure for different groups of urban and rural populations. The model has been verified with the results of over 10 thousand measurements of individual doses in inhabitants by means of thermoluminescent dosimeters. The stochastic model is being developed by forming the dose of external exposure in the population of a contaminated area, which allows to predict the dose distribution in critical groups of a population for the purposes of radiation protection. (author)

  3. A model for external dosimetry

    International Nuclear Information System (INIS)

    Henderson, R.W.; Coleman, J.B.

    1984-01-01

    This model was designed to estimate possible exposures from atmospheric testing. The FORTRAN 77 code follows an individual's living pattern as he or she moves about in a radiation field. The primary input is the time sequence of location changes relative to the individual's exposure. The changes from one shielding situation to another are stored and appropriate exposure modifiers assigned. These input data may be supplied directly, or assigned as generic information. Provision is made for following the individual through a series of changes representative of weekdays, Saturdays and Sundays. These data are also seasonally specific (one set each for spring, summer, fall and winter). The use of free formatting and item counting allows entry of the data on a day-by-day basis of any number of changes up to a given maximum. Exposure modifiers are currently input for five separate locations (bedroom, living room, public building, outdoors and a closed car). The model enters the tabulated data at any given time, selects the exposure modifier, the next change and calculates the free-in-air gamma exposure during the period from an exposure rate versus time function. The code then calculates the expected exposure using the exposure modifier. Accumulated exposures are converted to organ doses. The model estimates skin doses from beta particles as well as gamma radiation by accounting for periods of time out-of-doors and direct skin contamination. This entire program may be run deterministically (all input parameters constant) or stochastically with the various parameters selected from appropriate distributions, or as a combination of the two. Statistical information is derived from multiple executions of the stochastic version of the code. Results of representative executions are presented

  4. External radiation exposure after deposition of man-made radionuclides

    International Nuclear Information System (INIS)

    Jacob, P.

    1991-01-01

    The first step in assessing the external radiation exposure of the population is the determination of the gamma dose rate over meadows, which are used as reference points for various reasons. The second step is the description of external radiation exposures in urban and rural environments. The relation to the radiation exposure in a meadow is a function of the radionuclide distribution, i.e. the type of deposition. Finally, a simple method of calculating external radiation exposure is developed on the basis of recent findings. The method is compared with the method used in the UNSCEAR report for calculating radiation exposures after Chernobyl and with the method described in the AVV (General Administrative Regulation) of the Radiation Protection Ordinance. (orig./HP) [de

  5. External exposure assessment in dwelling built with phosphogypsum

    International Nuclear Information System (INIS)

    Villaverde, Freddy Lazo

    2008-01-01

    In this study it was evaluated the viability of the use of phosphogypsum plates as a building material in the dwelling construction. Thus, the effective dose due to external gamma exposure was assessed through the 226 Ra, 232 Th, 210 Pb e 40 K activity concentration in phosphogypsum plates. Samples of this material were analyzed by high resolution gamma spectrometry for their natural radionuclide activity concentration. The radium equivalent activity and extern ai and inter nai hazard indices were also calculated. The plates were made with phosphogypsum from fertilizer industries located in Cajati, Cubatao and Uberaba. The samples were identified according to phosphogypsum origin, Cajati (CA), Cubatao (CT) and Uberaba (UB). The activity concentrations results varied from 15.9 to 392 Bq kg -1 for 226 Ra, 26.1 to 253 Bq kg -1 for 232 Th, and 27.4 to 852 Bq kg -1 for 210 Pb. The results of 40 K were lower than 81 Bq kg -1 . The annual effective dose was obtained through the dosimetric model with reference standard room concept, the results were 0.02 mSv y -1 for a house built with phosphogypsum from origin CA, 0.2 mSvy -1 for CT phosphogypsum and 0.14 mSvy -1 for UB phosphogypsum, everything the effective doses were below 1 mSvy -1 , an annual effective dose limit for public exposure by International Commission on Radiological Protection. (author)

  6. External exposure due to natural radiation (KINKI)

    International Nuclear Information System (INIS)

    1978-01-01

    A field survey of exposure rates due to natural radiation has been conducted throughout the Kinki district of Japan during both September and October 1973. In each location, measurements of exposures at one to fifteen sites, one of where contained 5 stations at least, were made. A total of 143 sites were measured. Observations were made using a spherical ionization chamber and several scintillation surveymeters. The spherical plastic ionization chamber of which inner diameter and wall thickness are 200 mm and 3 mm (acrylate) respectively has adequate sensitivity for field survey. The chamber was used as a standard of apparatus, but it is difficult to use the apparatus in all locations only by the apparatus, so that a surveymeter with a NaI(Tl) 1''phi x 1'' scintillator was used for regular measurements. Two types of surveymeters, the one with a 2''phi x 2'' NaI(Tl) scintillator and the other with a 3''phi x 3'' NaI(Tl) scintillator, were used as auxiliary devices. Both the chamber and the surveymeter were used in 20 sites and their readings were compared for drawing a relationship between them. Practically the direct reading of the surveymeter were reduced into the corresponding value of the plastic chamber through the relationship of linear proportion. Systematic error at calibration ( 60 Co) and reading error (rodoh) of the plastic chamber were within +-6% (maximum over all error) and within +-3.5% (standard error for 6μ R/hr) respectively. Reading error of the surveymeter is about +-3% (standard error for 6μ R/hr). Measurements in open bare field were made at one meter above the ground and outdoor gamma-rays exposure rates (μ R/hr) were due to cosmic rays as well as terrestrial radiation, as it may be considered that the contribution of fallout due to artificial origin was very small. (J.P.N.)

  7. Exposures from external radiation and from inhalation of resuspended material

    International Nuclear Information System (INIS)

    Jacob, P.; Roth, P.; Golikov, V.; Balonov, M.; Erkin, V.; Likhtariov, I.; Garger, E.; Kashparov, V.

    1996-01-01

    In the modelling of external exposures due to cesium released during the reactor accident of Chernobyl, gamma dose rates in air over open undisturbed sites are considered to be different according to the unsoluble fraction in the deposit. This is taken into account by forming different classes according to the distance from the Chernobyl NPP. The effect of the different migration behavior in these distance classes on the gamma dose rate in air is found to increase with time. Predictions of gamma dose rates in air are based on measurements of the nuclear weapons tests fallout. Various population groups in the CIS countries are defined according to their place of residence (rural or urban), their occupation or age (indoor resp. outdoor workers, pensioners, school-children, or preschool-children), and their kind of residence (wooden, brick, or multi-storey house). Model results for various population groups are compared with the results of TLD-measurements of individual external exposures. For the calculation of inhalation doses, the new ICRP model for the respiratory tract was used. The dose assessments were conducted for measured size resolved activity distributions of resuspended material, obtained at different locations and for several kinds of agricultural operations. Inhalation doses vary considerably with respect to different kinds of work. Tractor drivers receive much higher doses than other agricultural workers, especially when the cabin window of the tractor is open. Effective doses due to the inhalation of resuspended plutonium are assessed to be a few μSv per initial deposit of one kBq/m 2 . Inhalation doses from 137 Cs are usually smaller by an order of magnitude than the doses from Pu, provided a high solubility is assumed for resuspended Cs

  8. Years of life lost due to external radiation exposure

    International Nuclear Information System (INIS)

    Raicevic, J.J.; Merkle, J.M.; Ehrhardt, J.; Ninkovic, M.M.

    2002-01-01

    A new approach for calculation of the years of life lost per excess death (YLL) due to stochastic health effects is applied to external exposure pathways. The short-term external exposures are due to the passage of radioactive cloud (CL) and due to the skin and clothes contamination (SK). The long-term external exposure is the one from the radioactive material deposited on ground (GR). Three nuclides, 131 I , 137 Cs and 239 Pu with extremely wide range of the half-life are considered to examine its possible influence on the calculated YLL values. For each of these nuclides, the YLL is found as a decreasing function of the age at exposure and presented graphically in this paper. Another negative correlation is established between the fully averaged YLL and the duration of the nuclide's half-life has been found for protracted exposure (GR). On the other hand, the YLL for the short-term external exposures (CL and SK) practically does not depend on the nuclide's half-life. In addition, a weak YLL dependence of the dose was commented. (author)

  9. Dose evaluation for external exposure in radiation accidents

    International Nuclear Information System (INIS)

    Maruyama, Takashi

    1989-01-01

    Abnormal exposures including emergency and accidental are categorized into external exposure and internal contamination, although both of these may be associated with external contamination. From a point of view of lifesaving in the abnormal exposures, it is primarily important to evaluate radiation dose of exposed persons as soon as possible. This report reviews the status of early dosimetry in the accidental exposures and discusses the optimum methodology of the early dose determination for external exposures in abnormal exposures. Personal monitors generally give an indication of dose to an exposed person only at a single part of the body. The data obtained from the personal monitors should be interpreted with care and in the light of information about the circumstances of exposure. In most cases, the records of environmental monitors or the survey with area monitors provide valuable information on the radiation fields. In the some cases, the reconstruction of the abnormal exposure is required for the dose evaluation by means of phantom experiments. In the case of neutron exposures, activation products in the body or its components or personnel possession can be useful for the early dosimetry. If the dose received by the whole body is evaluated as being very high, clinical observations and biological investigations may be more important guide to initial medical treatment than the early dosimetry. For the dose evaluation of general public, depending on the size of abnormal exposure, information that could be valuable in the assessment of abnormal exposures will come from the early dose estimates with environmental monitors and radiation survey meters. (author)

  10. Years of life lost due to external radiation exposure

    Directory of Open Access Journals (Sweden)

    Raičević Jagoš J.

    2004-01-01

    Full Text Available In this paper a new approach for calculation of the years of life lost per excess death due to stochastic health effects is applied to external exposure pathways. The short-term external exposures are due to the passage of radioactive cloud and due to the skin and clothes contamination. The long-term external exposure is the one from the radioactive material deposited on the ground (groundshine. Three nuclides, 131I, 137Cs, and 239Pu, and with the extremely wide range of half-life are considered in order to examine their possible influence on the calculated values of years of life lost. For each of these nuclides, the number of years of life lost has been found as a decreasing function of the age at the expo sure and presented graphically in this paper. For protracted exposures, the fully averaged number of years of life lost is negative correlated with the nuclide’s half-life. On the other hand, the short-term external exposures do not depend on the nuclide’s half-life. In addition, a weak years of life lost dependence of the dose has been commented.

  11. External gamma exposure to radon progeny in indoor air

    International Nuclear Information System (INIS)

    Fujimoto, Kenzo

    1985-01-01

    The external γ-exposure from radon progeny uniformly distributed in indoor air was estimated by a computer program that was developed. This program can calculate the fluence rate, exposure rate and average energy for any given point in a room of any given size. As numerical example, the exposure rate normalized to unit airborne activity is presented, together with the fluence-weighted and exposure-weighted average photon energies, for a room of representative geometry containing radon progeny in equilibrium. To cover other conditions encountered in practice, quantitative evaluations are additionally presented of the effect on the exposure brought by changes in certain parameters, such as equilibrium factor, wall thickness, room size and receptor position. The study has quantitatively substantiated the prevailing postulate that the effective dose equivalent due to external exposure resulting from normal indoor concentrations of airborne radon progeny in the room of representative geometry should only amount to 0.04 % of that from the internal exposure from the same sources, and that it should be of similarly negligible order compared with internal exposure also in the case of other room geometries. (author)

  12. The treatment progress of radiation dermatitis from external exposure

    International Nuclear Information System (INIS)

    Pu Wangyang; Liu Yulong

    2009-01-01

    Radiation dermatitis is often seen and is often a complication of radiation therapy of tumors. It is characterized by poor healing, stubborn relapse, and carcinogenesis.. The treatment include drug, physical therapy and surgery. This article describes the treatment progress of radiation dermatitis from external exposure. (authors)

  13. External exposure to radionuclides in air, water, and soil

    International Nuclear Information System (INIS)

    Eckerman, K.F.; Ryman, J.C.

    1996-01-01

    Federal Guidance Report No. 12 tabulates dose coefficients for external exposure to photons and electrons emitted by radionuclides distributed in air, water, and soil. The dose coefficients are intended for use by Federal Agencies in calculating the dose equivalent to organs and tissues of the body

  14. Geochemistry Model Validation Report: External Accumulation Model

    International Nuclear Information System (INIS)

    Zarrabi, K.

    2001-01-01

    The purpose of this Analysis and Modeling Report (AMR) is to validate the External Accumulation Model that predicts accumulation of fissile materials in fractures and lithophysae in the rock beneath a degrading waste package (WP) in the potential monitored geologic repository at Yucca Mountain. (Lithophysae are voids in the rock having concentric shells of finely crystalline alkali feldspar, quartz, and other materials that were formed due to entrapped gas that later escaped, DOE 1998, p. A-25.) The intended use of this model is to estimate the quantities of external accumulation of fissile material for use in external criticality risk assessments for different types of degrading WPs: U.S. Department of Energy (DOE) Spent Nuclear Fuel (SNF) codisposed with High Level Waste (HLW) glass, commercial SNF, and Immobilized Plutonium Ceramic (Pu-ceramic) codisposed with HLW glass. The scope of the model validation is to (1) describe the model and the parameters used to develop the model, (2) provide rationale for selection of the parameters by comparisons with measured values, and (3) demonstrate that the parameters chosen are the most conservative selection for external criticality risk calculations. To demonstrate the applicability of the model, a Pu-ceramic WP is used as an example. The model begins with a source term from separately documented EQ6 calculations; where the source term is defined as the composition versus time of the water flowing out of a breached waste package (WP). Next, PHREEQC, is used to simulate the transport and interaction of the source term with the resident water and fractured tuff below the repository. In these simulations the primary mechanism for accumulation is mixing of the high pH, actinide-laden source term with resident water; thus lowering the pH values sufficiently for fissile minerals to become insoluble and precipitate. In the final section of the model, the outputs from PHREEQC, are processed to produce mass of accumulation

  15. External exposure from radionuclides in soil: analytical vs. simulation procedures

    International Nuclear Information System (INIS)

    Velasco, Hugo; Rizzotto, Marcos

    2008-01-01

    Full text: The external gamma irradiation resulting from radionuclides deposited on the ground surface can be an important source of radiation exposure. The assessment of this irradiation is extremely complex due to the large number of environmental factors which affect the gamma photon flux in air originating from the ground. The source energy affects the interaction between the radiation and the medium, and the characteristics and the properties of the soil are the most relevant factors to determine the energy and the angular distribution of gamma radiation in air 1 m above the ground surface. From an analytical point of view the calculations are based on the point-kernel integration method and assume that the source concentration at any depth in soil is uniform over an infinite surface parallel to the ground plane. The dose-rate factor is applied to environmental dose assessments by means of the general equation: H(t)= χ (t) x DRF where H is the external dose rate at time t, χ is the source concentration at the location of the exposed individual, and DRF is the dose-rate factor. Dose-rate factors in air at a height of 1 m above ground are tabulated for discrete photon energies between 0.01 and 10 MeV and for source depths in soil between 0 and 300 cm. These factors were determined for sources distributed in a slab of finite thickness and sources which are exponentially distributed with depth. A Monte Carlo algorithm was developed to simulate the gamma photons transport calculation for the soil/air configuration. In this case the soil constituents were assumed to be similar to those on the earth's crust. The model considers the gamma photons source distributed uniformly in the soil profile, from the ground surface to a depth beyond which the soil is considered uncontaminated. Source gamma photons were randomly selected from the contaminated soil zone and their subsequent interactions determined by the probability of occurrence via photoelectric effect, Compton

  16. Applied physics of external radiation exposure dosimetry and radiation protection

    CERN Document Server

    Antoni, Rodolphe

    2017-01-01

    This book describes the interaction of living matter with photons, neutrons, charged particles, electrons and ions. The authors are specialists in the field of radiation protection. The book synthesizes many years of experiments with external radiation exposure in the fields of dosimetry and radiation shielding in medical, industrial and research fields. It presents the basic physical concepts including dosimetry and offers a number of tools to be used by students, engineers and technicians to assess the radiological risk and the means to avoid them by calculating the appropriate shields. The theory of radiation interaction in matter is presented together with empirical formulas and abacus. Numerous numerical applications are treated to illustrate the different topics. The state of the art in radiation protection and dosimetry is presented in detail, especially in the field of simulation codes for external exposure to radiation, medical projects and advanced research. Moreover, important data spread in differ...

  17. External exposure in radionuclide therapy with 153 Sm

    Energy Technology Data Exchange (ETDEWEB)

    Rezio, M.T.; Vieira, M.R. [Instituto Portugues Oncologia de Francisco Gentil, CROL, Lisboa (Portugal)

    2006-07-01

    Full text of publication follows: Aim: The radiopharmaceutical 153 Sm is an beta emitter used in metastatic bone pain palliation. The prescribed activity is 37 MBq/kg body weight.. The aim of this study is to measure the dose rate of the patients during 4 to 6 hours after 153 Sm - E.D.T.M.P. administration in order to prevent external exposure of nursing staff, family members and general public. Material and Methods: Twelve patients were treated with 153 Sm in our department. External exposure rates( {mu}Sv/h) at different times and at one meter were measured, with a Geiger-Muller detector. Results: The mean dose rate at one meter was 12 {mu}Sv/h, one hour after injection and 3{mu} Sv/h, 6 hours after injection. Conclusion: The policy in our department is to keep the patient in the hospital 4-6 h, due to the risk of contamination. Based on our results, the external exposure of the nursing staff, family members and the general public is very low, in agreement with other studies. (authors)

  18. External exposure in radionuclide therapy with 153 Sm

    International Nuclear Information System (INIS)

    Rezio, M.T.; Vieira, M.R.

    2006-01-01

    Full text of publication follows: Aim: The radiopharmaceutical 153 Sm is an beta emitter used in metastatic bone pain palliation. The prescribed activity is 37 MBq/kg body weight.. The aim of this study is to measure the dose rate of the patients during 4 to 6 hours after 153 Sm - E.D.T.M.P. administration in order to prevent external exposure of nursing staff, family members and general public. Material and Methods: Twelve patients were treated with 153 Sm in our department. External exposure rates( μSv/h) at different times and at one meter were measured, with a Geiger-Muller detector. Results: The mean dose rate at one meter was 12 μSv/h, one hour after injection and 3μ Sv/h, 6 hours after injection. Conclusion: The policy in our department is to keep the patient in the hospital 4-6 h, due to the risk of contamination. Based on our results, the external exposure of the nursing staff, family members and the general public is very low, in agreement with other studies. (authors)

  19. Exposure of a liquefied gas container to an external fire

    International Nuclear Information System (INIS)

    Raj, Phani K.

    2005-01-01

    In liquefied gas, bulk-storage facilities and plants, the separation distances between storage tanks and between a tank and a line of adjoining property that can be built are governed by local regulations and/or codes (e.g. National Fire Protection Association (NFPA) 58, 2004). Separation distance requirements have been in the NFPA 58 Code for over 60 years; however, no scientific foundations (either theoretical or experimental) are available for the specified distances. Even though the liquefied petroleum gas (LPG) industry has operated safely over the years, there is a question as to whether the code-specified distances provide sufficient safety to LPG-storage tanks, when they are exposed to large external fires. A radiation heat-transfer-based model is presented in this paper. The temporal variation of the vapor-wetted tank-wall temperature is calculated when exposed to thermal radiation from an external, non-impinging, large, 30.5 m (100 ft) diameter, highly radiative, hydrocarbon fuel (pool) fire located at a specified distance. Structural steel wall of a pressurized, liquefied gas container (such as the ASME LP-Gas tank) begins to lose its strength, when the wall temperature approaches a critical temperature, 810 K (1000 deg F). LP-Gas tank walls reaching close to this temperature will be a cause for major concern because of increased potential for tank failure, which could result in catastrophic consequences. Results from the model for exposure of different size ASME (LP-Gas) containers to a hydrocarbon pool fire of 30.5 m (100 ft) in diameter, located with its base edge at the separation distances specified by NFPA 58 [NFPA 58, Liquefied Petroleum Gas Code, Table 6.3.1, 2004 ed., National Fire Protection Association, Quincy, MA, 2004] indicate that the vapor-wetted wall temperature of the containers never reach the critical temperature under common wind conditions (0, 5 and 10 m/s), with the flame tilting towards the tank. This indicates that the separation

  20. Review of retrospective dosimetry techniques for external ionising radiation exposures

    International Nuclear Information System (INIS)

    Ainsbury, E. A.; Bakhanova, E.; Barquinero, J. F.; Brai, M.; Chumak, V.; Correcher, V.; Darroudi, F.; Fattibene, P.; Gruel, G.; Guclu, I.; Horn, S.; Jaworska, A.; Kulka, U.; Lindholm, C.; Lloyd, D.; Longo, A.; Marrale, M.; Monteiro Gil, O.; Oestreicher, U.; Pajic, J.; Rakic, B.; Romm, H.; Trompier, F.; Veronese, I.; Voisin, P.; Vral, A.; Whitehouse, C. A.; Wieser, A.; Woda, C.; Wojcik, A.; Rothkamm, K.

    2011-01-01

    The current focus on networking and mutual assistance in the management of radiation accidents or incidents has demonstrated the importance of a joined-up approach in physical and biological dosimetry. To this end, the European Radiation Dosimetry Working Group 10 on 'Retrospective Dosimetry' has been set up by individuals from a wide range of disciplines across Europe. Here, established and emerging dosimetry methods are reviewed, which can be used immediately and retrospectively following external ionising radiation exposure. Endpoints and assays include dicentrics, translocations, premature chromosome condensation, micronuclei, somatic mutations, gene expression, electron paramagnetic resonance, thermoluminescence, optically stimulated luminescence, neutron activation, haematology, protein biomarkers and analytical dose reconstruction. Individual characteristics of these techniques, their limitations and potential for further development are reviewed, and their usefulness in specific exposure scenarios is discussed. Whilst no single technique fulfils the criteria of an ideal dosemeter, an integrated approach using multiple techniques tailored to the exposure scenario can cover most requirements. (authors)

  1. Trauma Exposure and Externalizing Disorders in Adolescents: Results From the National Comorbidity Survey Adolescent Supplement.

    Science.gov (United States)

    Carliner, Hannah; Gary, Dahsan; McLaughlin, Katie A; Keyes, Katherine M

    2017-09-01

    Exposure to violence and other forms of potentially traumatic events (PTEs) are common among youths with externalizing psychopathology. These associations likely reflect both heightened risk for the onset of externalizing problems in youth exposed to PTEs and elevated risk for experiencing PTEs among youth with externalizing disorders. In this study, we disaggregate the associations between exposure to PTEs and externalizing disorder onset in a population-representative sample of adolescents. We analyzed data from 13- to 18-year-old participants in the National Comorbidity Survey Replication-Adolescent Supplement (NCS-A) (N = 6,379). Weighted survival models estimated hazard ratios (HRs) for onset of oppositional defiant disorder (ODD), conduct disorder (CD), and substance use disorders (SUDs) associated with PTEs, and for exposure to PTEs associated with prior-onset externalizing disorders. Multiplicative interaction terms tested for effect modification by sex, race/ethnicity, and household income. All types of PTEs were associated with higher risk for SUD (HRs = 1.29-2.21), whereas only interpersonal violence (HR = 2.49) was associated with onset of CD and only among females. No associations were observed for ODD. Conversely, ODD and CD were associated with elevated risk for later exposure to interpersonal violence and other/nondisclosed events (HRs = 1.45-1.75). Externalizing disorders that typically begin in adolescence, including SUDs and CD, are more likely to emerge in adolescents with prior trauma. ODD onset, in contrast, is unrelated to trauma exposure but is associated with elevated risk of experiencing trauma later in development. CD and interpersonal violence exposure exhibit reciprocal associations. These findings have implications for interventions targeting externalizing and trauma-related psychopathology. Copyright © 2017 American Academy of Child and Adolescent Psychiatry. Published by Elsevier Inc. All rights reserved.

  2. Energy and externality environmental regional model

    International Nuclear Information System (INIS)

    Baldi, L.; Bianchi, A.; Peri, M.

    2000-01-01

    The use of environmental externalities in both territorial management and the direction of energy and environment, faces the difficulties arising from their calculation. The so-called MACBET regional model, which has been constructed for Lombardy, is a first brand new attempt to overcome them. MACBET is a calculation model to assess environmental and employment externalities connected to energy use [it

  3. External radiation exposure control system in accelerator facilities

    International Nuclear Information System (INIS)

    Ogawa, Tatsuhiko; Iimoto, Takeshi; Kosako, Toshiso

    2011-01-01

    The external exposure control systems in KEK and CERN are discussed to find out good practices and unreasonableness of radiation control in accelerator facilities, which plays an important role in optimizing national and/or site specific radiological regulations, referring to relevant ICRP publications. Personal dose limits and radiation area classifications were analyzed and their reasonableness were explored. Good example of supervised areas, area classification based on realistic assumptions on working time etc are found. On the other hand, unreasonable systems, that are often attributed to the national regulation or ideas presented in the old publications are also found. (author)

  4. Internal and external radiation exposures of Fukushima residents

    International Nuclear Information System (INIS)

    Hayano, Ryugo

    2014-01-01

    The soil at Fukushima prefecture and its outskirts was heavily contaminated with radioactive materials from the troubled Fukushima Daiichi nuclear power plant, and the residents suffered risk from internal and external radiation exposure. At first, the average dose of internal radiation exposure was estimated to be several mSv based upon the results of Chernobyl nuclear disaster. But the result of massive measurements using whole body counters shows that the average quantity of internal radioactive cesium is less than that at the Cold Water period. In the meantime, someone shows exposure dose much higher than the average. The distribution of these abnormal doses is called 'Long Tail'. One must pay attention to the long tail at the assessment of the internal radiation exposure by Fukushima nuclear disaster. The main origin of the long tail is related to frequency eating of special food. It is thus important to find persons situated in the long tail and give them guidance on the meals. (J.P.N.)

  5. Explanation of nurse standard of external exposure acute radiation sickness

    International Nuclear Information System (INIS)

    Lu Xiuling; Jiang Enhai; Sun Feifei; Zhang Bin; Wang Xiaoguang; Wang Guilin

    2012-01-01

    National occupational health standard-Nurse Standard of External Exposure Acute Radiation Sickness has been approved and issued by the Ministry of Health. Based on the extensive research of literature, collection of the previous nuclear and radiation accidents excessive exposed personnel data and specific situations in China, this standard was enacted according to the current national laws, regulations, and the opinions of peer experts. It is mainly used for care of patients with acute radiation sickness, and also has directive significance for care of patients with iatrogenic acute radiation sickness which due to the hematopoietic stem cell transplantation pretreatment. To correctly carry out this standard and to reasonably implement nursing measures for patients with acute radiation sickness, the contents of this standard were interpreted in this article. (authors)

  6. Late biological effects from internal and external exposure

    International Nuclear Information System (INIS)

    Adams, W.H.

    1985-01-01

    Information on late biological effects of radiation was obtained from the long-term medical followup of a small population of Marshallese accidentally exposed to radioactive fallout from a thermonuclear test in 1954. Endocrine data are compatible with a sequence of nonstochastic radiation effects. The ingestion of radioisotopes of iodine produced clinical thyroid hypofunction in children, biochemical evidence of thyroid dysfunction in some adults, thyroid adenomatous module formation, and, as a possible indirect effect of thyroid damage, at least two cases of pituitary adenoma. In contrast, the only evidence of a stochastic effect has been a real increase in thyroid cancers among the more highly exposed people of Rongelap, none of whom have evidence of residual disease. While three nonthyroidal cancers which are known to be inducible in humans by external irradiation have been documented in the exposed population, three similar cancers have occurred in an unexposed comparison population of Marshallese. Nonstochastic effects of radiation exposure may be common but subtle. In the Marshallese experience the morbidity of delayed nonstochastic effects far exceeds that of the stochastic. 20 refs., 5 figs., 1 tab

  7. Probabilistic dietary exposure models

    NARCIS (Netherlands)

    Boon, Polly E.; Voet, van der H.

    2015-01-01

    Exposure models are used to calculate the amount of potential harmful chemicals ingested by a human population. Examples of harmful chemicals are residues of pesticides, chemicals entering food from the environment (such as dioxins, cadmium, lead, mercury), and chemicals that are generated via

  8. Determinants of Dermal Exposure Relevant for Exposure Modelling in Regulatory Risk Assessment

    NARCIS (Netherlands)

    Marquart, J.; Brouwer, D.H.; Gijsbers, J.H.J.; Links, I.H.M.; Warren, N.; Hemmen, J.J. van

    2003-01-01

    Risk assessment of chemicals requires assessment of the exposure levels of workers. In the absence of adequate specific measured data, models are often used to estimate exposure levels. For dermal exposure only a few models exist, which are not validated externally. In the scope of a large European

  9. Modelling exposure opportunities

    DEFF Research Database (Denmark)

    Sabel, Clive E.; Gatrell, Anthony C.; Löytönen, Markku

    2000-01-01

    This paper addresses the issues surrounding an individual's exposure to potential environmental risk factors, which can be implicated in the aetiology of a disease. We hope to further elucidate the 'lag' or latency period between the initial exposure to potential pathogens and the physical...... boundaries.We use kernel estimation to model space-time patterns. Raised relative risk is assessed by adopting appropriate adjustments for the underlying population at risk, with the use of controls. Significance of the results is assessed using Monte Carlo simulation, and comparisons are made with results...

  10. Methodology of external exposure calculation for reuse of conditional released materials from decommissioning - 59138

    International Nuclear Information System (INIS)

    Ondra, Frantisek; Vasko, Marek; Necas, Vladimir

    2012-01-01

    The article presents methodology of external exposure calculation for reuse of conditional released materials from decommissioning using VISIPLAN 3D ALARA planning tool. Production of rails has been used as an example application of proposed methodology within the CONRELMAT project. The article presents a methodology for determination of radiological, material, organizational and other conditions for conditionally released materials reuse to ensure that workers and public exposure does not breach the exposure limits during scenario's life cycle (preparation, construction and operation of scenario). The methodology comprises a proposal of following conditions in the view of workers and public exposure: - radionuclide limit concentration of conditionally released materials for specific scenarios and nuclide vectors, - specific deployment of conditionally released materials eventually shielding materials, workers and public during the scenario's life cycle, - organizational measures concerning time of workers or public stay in the vicinity on conditionally released materials for individual performed scenarios and nuclide vectors. The above mentioned steps of proposed methodology have been applied within the CONRELMAT project. Exposure evaluation of workers for rail production is introduced in the article as an example of this application. Exposure calculation using VISIPLAN 3D ALARA planning tool was done within several models. The most exposed profession for scenario was identified. On the basis of this result, an increase of radionuclide concentration in conditional released material was proposed more than two times to 681 Bq/kg without no additional safety or organizational measures being applied. After application of proposed safety and organizational measures (additional shielding, geometry changes and limitation of work duration) it is possible to increase concentration of radionuclide in conditional released material more than ten times to 3092 Bq/kg. Storage

  11. Quality assurance of external exposure measurement for national survey of environmental natural radioactive level

    International Nuclear Information System (INIS)

    Yue Qingyu

    1995-01-01

    This paper summarizes the quality assurance work of external exposure measurement for national survey of environmental natural radioactive level. It mainly introduces instrumentation used in external exposure measurement and its properties, the measurement results of three times of national in-site intercomparison, and in-site sample check results of measurement results from 29 provinces, cities and autonomous regions and Wuhan, Baotou cities

  12. Dose Record Analysis of External Exposure of Workers in Madagascar

    International Nuclear Information System (INIS)

    Andriambololona, R.; Ratovonjanahary, J. F.; Randriantsizafy, R. D.

    2004-01-01

    External personnel monitoring of workers in diagnostic radiology in Madagascar using thermoluminescence techniques has been studied in previous work for the period of 1990 to 2000. The study was based on the average of Hp(0.07) and Hp(10) and on the annual dose distribution. The results showed that mean doses are very low compared with the annual dose limits for workers of 20 mSv per year and are comparable with natural contribution of telluric X and gamma exposure which is evaluated as 3.21 mSv per year in Antananarivo. No trend in the average was observed, however, the last 4 years, the results showed a substantial decrease in the average from 2 mSv to 1 mSv. It was assumed that this was the impact of the implementation by radiation staff in their workplace of the in force regulation which is in compliance with the new basic safety standards. Indeed, since 1996, Madagascar-Institut National des Sciences et Techniques Nucleaires (Madagascar-INSTN) and the Association Nationale de Radioprotection de Madagascar (ANARAPMAD), the Madagascar radiation protection society and associate member of IRPA, set up a national program for training of radiation workers. The number of workers trained during this period is evaluated as 50% of the total number of radiation workers in Madagascar. The present work is a continuation of the above mentioned survey during the period of 2001 to 2003. The training program was upgraded to involve personnel who will be in charge of radiation protection and safety in workplace and the training cycle lasts 2 years instead of 3 days in the previous program. The survey has been extended to include all radiation workers in Madagascar though the medical field is still the main application and represents more than 90 percent of the latter. The results shows that for this last 3 years, an other substantial decrease from 1 mSv to 0.5 mSv was observed in the average. In the dose distribution, more than 98 percent of the Hp(0.07) and more than 99

  13. Urbapat: External exposure and countermeasures after a radiological accident in the urban environment

    International Nuclear Information System (INIS)

    Martin, J.E.; Gallego, E.

    1992-01-01

    URBAPAT (URBAN PATHWAY) is a computer model, written in FORTRAN 77, for the evaluation of the gamma external exposure, and the adequate countermeasures, after a radiological accident involving dispersion and deposition of radioactive material on different urban surfaces. The code estimates the evolution of radioactive material in the urban environment using a dynamic model consisting on 21 compartments, that simulate five different urban surfaces with their particular retention properties. For the assessment of the gamma external exposure in urban areas, one of then main contributors to the long-term individual dose, the model considers the contribution of each surface to the dose rate delivered by five radionuclides (Cs-137, Cs-134, I-131, Te-132, Ba-140) in different locations outside and inside three types of buildings (semi-detached houses, terrace houses and multi-stored buildings). The population is classified in various groups, attending to their stay time in each location. The model can evaluate the dose avoided by the introduction of countermeasures like decontamination of the urban surfaces or relocation. An assessment of their associated costs will permit to perform the needed cost-benefit analysis of the different countermeasures and alternatives, following IAEA and ICRP recommendations. The capability to perform sensitivity and uncertainty assessment of the more important parameters affecting the results obtained will also be included in the model. (Author)

  14. Stochastic health effects assessment due to short-term external exposure

    International Nuclear Information System (INIS)

    Raicevic, J.J.; Raskob, W.; Merkle, M.; Ninkovic, M.M.

    2001-01-01

    The new model for calculation of stochastic health effects is presented in this paper. The exposure pathways which are briefly considered are the short-term external exposure due to passage of the radioactive cloud (cloudshine) and the short-term external exposure due to radioactive material deposited on skin and clothes (skin contamination). The quantitative assessment of stochastic effects is expressed in numbers of deaths, which are given as a functions of the time at the accident, and age at death, what on the other side enables estimation of the number of deaths within the specified range of the time/age parameters. That means the model calculates the number of deaths within one particular year, summed up over all ages at deaths, or vice versa, it finds the number of deaths within the specified range of ages at death, summed up over all observation times. Results presented in this paper are implemented in the module LATEHEAL, which is incorporated in RODOS, a new European system for decision support for nuclear emergencies. (author)

  15. External momentum expansion in NJL model

    International Nuclear Information System (INIS)

    Huang Mei; Zhao Weiqin; Zhuang Pengfei

    1999-01-01

    In the large N c expansion beyond mean-field approximation, the authors develop a general scheme of SU(2) NJL model including current quark mass explicitly. In the scheme, the constituent quark's propagator is expanded in pions external momentum k, and all the Feynman diagrams are naturally expanded to k 2 term in a unified way. The numerical results show that in the mean field approximation, the effect of current quark mass is invisible, however, the effect of current quark mass can be seen explicitly beyond mean-field approximation for reasonable choices of the parameters in NJL model

  16. Near Infrared Photoimmunotherapy with Combined Exposure of External and Interstitial Light Sources.

    Science.gov (United States)

    Maruoka, Yasuhiro; Nagaya, Tadanobu; Sato, Kazuhide; Ogata, Fusa; Okuyama, Shuhei; Choyke, Peter L; Kobayashi, Hisataka

    2018-02-21

    Near infrared photoimmunotherapy (NIR-PIT) is a new target-cell-specific cancer treatment that induces highly selective necrotic/immunogenic cell death after systemic administration of a photoabsorber antibody conjugate and subsequent NIR light exposure. However, the depth of NIR light penetration in tissue (approximately 2 cm) with external light sources limits the therapeutic effects of NIR-PIT. Interstitial light exposure using cylindrical diffusing optical fibers can overcome this limitation. The purpose in this study was to compare three NIR light delivery methods for treating tumors with NIR-PIT using a NIR laser system at an identical light energy; external exposure alone, interstitial exposure alone, and the combination. Panitumumab conjugated with the photoabsorber IRDye-700DX (pan-IR700) was intravenously administered to mice with A431-luc xenografts which are epithelial growth factor receptor (EGFR) positive. One and 2 days later, NIR light was administered to the tumors using one of three methods. Interstitial exposure alone and in combination with external sources showed the greatest decrease in bioluminescence signal intensity. Additionally, the combination of external and interstitial NIR light exposure showed significantly greater tumor size reduction and prolonged survival after NIR-PIT compared to external exposure alone. This result suggested that the combination of external and interstitial NIR light exposure was more effective than externally applied light alone. Although external exposure is the least invasive means of delivering light, the combination of external and interstitial exposures produces superior therapeutic efficacy in tumors greater than 2 cm in depth from the tissue surface.

  17. Adequacy of individual monitoring of external exposure at the workplace

    International Nuclear Information System (INIS)

    Rannou, A.

    2006-01-01

    Individual monitoring of workers exposed to external radiations must fulfill technical, regulatory and organizational requirements. The external dosimetry should be adapted to the workplace. The relevant dosimetric techniques have to be chosen upon the workplace study that conditions both the categorization of exposed workers and classification of areas. Solutions exist which are satisfactory for the most situations. However, rational solutions still have to be found for a few specific situations. (author)

  18. Occupational external radiation exposure in the GDR in 1976

    International Nuclear Information System (INIS)

    Rothe, W.

    1980-01-01

    In 1976 a total of 36,794 occupationally exposed persons were monitored by the National Board of Nuclear Safety and Radiation Protection, using film badges. The monthly over-exposures (more than 4 mGy) totalled 415. In 11 cases the monthly exposure exceeded 30 mGy and 6 annual exposure values were in the range of 50 to 120 mGy. An attempt has been made to assess the annual collective and annual per caput doses for the exposed population as a whole and some subgroups without completely summing up the individual exposure data. (author)

  19. Calculation of conversion coefficients for radiological protection against external radiation exposures

    International Nuclear Information System (INIS)

    Zankl, M.

    2001-01-01

    Calculations are essential for radiation protection practice because organ doses and effective doses cannot be measured directly. Conversion coefficients describe the numerical relationships of protection quantities and operational quantities. The latter can be measured in practical situations using suitable dosimeters. The conversion coefficients are calculated using radiation transport codes - usually based on Monte Carlo methods - that simulate the interactions of radiation with matter in computational models of the human body. A new generation of human body models, the so-called voxel models, are constructed from image data of real persons using suitable image processing systems, consequently, they represent the human anatomy more realistically than the so-called mathematical models. The numerical effects of realistic body anatomy on the calculated conversion coefficients can amount to 70% and more for external exposures. (orig.) [de

  20. Fertility of women after exposure to internal and external radiation

    International Nuclear Information System (INIS)

    Polednak, A.P.

    1982-01-01

    Fertility was examined in 199 women exposed to internal and external radiation while employed in the radium watch-dial painting industry in Illinois between 1916 and 1929. In women with at least one live birth, mean log live-birth rate was significantly lower in the highest (estimated) ovarian-dose group (i.e., greater than or equal to 20 rem) than in the lowest group (<5 rem). In multiple regression analysis, intake dose (proportional to alpha-particle dose to ovaries) but not duration of employment (relevant to external gamma-ray dose to ovaries) was a statistically significant predictor of log live-birth rate. There was no evidence for an increase in fetal deaths with increasing ovarian dose level (rem). This suggests that the findings on live-birth rate may not involve post-implantation dominant lethal mutations, but pre-implantation losses could not be evaluated. Some possible explanations for these findings are discussed

  1. Fertility of women after exposure to internal and external radiation

    International Nuclear Information System (INIS)

    Polednak, A.P.

    1980-01-01

    Fertility was examined in 199 women exposed to internal and external radiation while employed in the radium watch-dial painting industry in Illinois between 1916 and 1929. In women with at least one live birth, mean log live-birth rate was significantly lower in the highest (estimated) ovarian-dose group (i.e., greater than or equal to 20 rem) than in th lowest group (<5 rem). In multiple regression analysis, intake dose (proportional to alpha-particle dose to ovaries) but not duration of employment (relevant to external gamma-ray dose to ovaries) was a statistically significant predictor of log live-birth rate. There was no evidence for an increase in fetal deaths with increasing ovarian dose level (rem). This suggests that the findings on live-birth rate may not involve post-implantation dominant lethal mutations, but preimplantation losses could not be evaluated. Some possible explanations for these findings are discussed

  2. 1976 Hanford americium-exposure incident: external decontamination procedures

    International Nuclear Information System (INIS)

    Jech, J.J.; Berry, J.R.; Breitenstein, B.D.

    1982-01-01

    An accident resulted in the deposition on an injured workman's skin surfaces, in acid-burned areas and in lacerations, of something in excess of 6 mCi americium-241. The external decontamination procedures used, the change in americium content of the skin during the course of treatment, and some of the unusual problems encountered from the extrusion of foreign material and flaking of skin and scar tissue are described

  3. Patterns of poverty exposure and children’s trajectories of externalizing and internalizing behaviors

    Directory of Open Access Journals (Sweden)

    Jinette Comeau

    2018-04-01

    Full Text Available Using data from the Child Supplement of the National Longitudinal Survey of Youth, we compare trajectories of externalizing and internalizing behaviors among children exposed to five patterns of poverty from birth to age 14: always or never poor – stable patterns; a single transition into or out of poverty, or repeated fluctuations in and out of poverty – changing patterns. We also examine how low maternal education and single parenthood interact with these poverty exposures to compound their adverse effects. Finally, we compare the magnitude of effects associated with the patterns of poverty exposure, as well as their interactions with low maternal education and single parenthood, on trajectories of externalizing and internalizing behaviors to determine if they are significantly different. Results reveal that initial levels and rates of change in children’s trajectories of externalizing and internalizing behaviors are similar across the three changing patterns of poverty exposure, leading us to combine them into a single group representing intermittent poverty. Initial disparities between children who are never poor and their counterparts who are always or intermittently poor are constant over time for internalizing behaviors and grow in magnitude for externalizing behaviors. The cumulative negative effect of poverty exposure over time is stronger for externalizing vs. internalizing behaviors. Low maternal education compounds the adverse effects of persistent poverty, an effect that is similar for externalizing and internalizing behaviors. Keywords: United States, Poverty, Child mental health disparities, Externalizing behaviors, Internalizing behaviors, Multiple risk exposure

  4. Bibliography - Existing Guidance for External Hazard Modelling

    International Nuclear Information System (INIS)

    Decker, Kurt

    2015-01-01

    The bibliography of deliverable D21.1 includes existing international and national guidance documents and standards on external hazard assessment together with a selection of recent scientific papers, which are regarded to provide useful information on the state of the art of external event modelling. The literature database is subdivided into International Standards, National Standards, and Science Papers. The deliverable is treated as a 'living document' which is regularly updated as necessary during the lifetime of ASAMPSA-E. The current content of the database is about 140 papers. Most of the articles are available as full-text versions in PDF format. The deliverable is available as an EndNote X4 database and as text files. The database includes the following information: Reference, Key words, Abstract (if available), PDF file of the original paper (if available), Notes (comments by the ASAMPSA-E consortium if available) The database is stored at the ASAMPSA-E FTP server hosted by IRSN. PDF files of original papers are accessible through the EndNote software

  5. External and internal exposure to natural radiations inside ancient Egyptian tombs in Saqqara

    Energy Technology Data Exchange (ETDEWEB)

    Abo-Elmagd, M [National Institute for Standard, Radiation Measurements Department, P.O. Box 136 Giza code no. 12211 (Egypt); Metwally, S M [Faculty of Science, Department of Physics, Ain Shams University, P.O. Box 11566, Cairo (Egypt); Elmongy, S A [Atomic Energy Authority, Nuclear Safety, Cairo (Egypt); Salama, E [Faculty of Science, Department of Physics, Ain Shams University, P.O. Box 11566, Cairo (Egypt); El-Fiki, S A [Faculty of Science, Department of Physics, Ain Shams University, P.O. Box 11566, Cairo (Egypt)

    2006-02-15

    Some ancient Egyptian tombs in Saqqara are closed for visit to undergo fixation processes. The workers inside these tombs exposed to natural radiations from natural Gamma emitters (external exposure) and inhale unknown radon doses (internal exposure) for long periods. The external exposure in all studied tombs is lower than the maximum recommended action level. The internal exposure in terms of annual effective dose in the south tomb is equal to 28.83mSv/year which highly exceed the recommended level (3-10mSv/year). In this tomb, the external exposure is equal to 21.43{mu}Sv/year. This reflects the hazards of radon over the other natural radiations in the closed area. Among the workers inside the studied tombs, the expected morality is equal to 0.0033%, 0.0199% and 0.0724% for the south entrance of Zoser pyramid, the Serapeum tomb, and the south tomb respectively. ctively.

  6. Estimation of effective dose to public from external exposure to natural background radiation in saudi arabia

    International Nuclear Information System (INIS)

    Khalid, A. A.

    2003-01-01

    The effective dose values in sixteen cities in Saudi Arabia due to external exposure to natural radiation were evaluated. These doses are based on natural background components including external exposure to terrestrial radiation and cosmic rays. The importance of evaluating the effective dose to the public due to external exposure to natural background radiation lies in its epidemiological and dosimetric importance and in forming a basis for the assessment of the level of radioactive contamination or pollution in the environment in the future. The exposure to terrestrial radiation was measured using thermoluminescent dosimeters (TLD). The exposure from cosmic radiation was determined using empirical correlation. The values evaluated for the total annual effective dose in all cities were within the world average values. The highest total annual effective dose measured in Al-Khamis city was 802 μSv/y, as compared to 305 μSv/y in Dammam city, which was considered the lowest value

  7. External and internal exposure to natural radiations inside ancient Egyptian tombs in Saqqara

    International Nuclear Information System (INIS)

    Abo-Elmagd, M.; Metwally, S.M.; Elmongy, S.A.; Salama, E.; El-Fiki, S.A.

    2006-01-01

    Some ancient Egyptian tombs in Saqqara are closed for visit to undergo fixation processes. The workers inside these tombs exposed to natural radiations from natural Gamma emitters (external exposure) and inhale unknown radon doses (internal exposure) for long periods. The external exposure in all studied tombs is lower than the maximum recommended action level. The internal exposure in terms of annual effective dose in the south tomb is equal to 28.83mSv/year which highly exceed the recommended level (3-10mSv/year). In this tomb, the external exposure is equal to 21.43μSv/year. This reflects the hazards of radon over the other natural radiations in the closed area. Among the workers inside the studied tombs, the expected morality is equal to 0.0033%, 0.0199% and 0.0724% for the south entrance of Zoser pyramid, the Serapeum tomb, and the south tomb respectively. ctively

  8. Thyroid doses from external gamma-exposure following the Chernobyl accident

    International Nuclear Information System (INIS)

    Tretyakevich, Sergey; Kukhta, Tatyana; Minenko, Victor; Drozdovitch, Vladimir; Luckyanov, Nickolas; Gavrilin, Yury; Khrouch, Valeri; Shinkarev, Sergey

    2008-01-01

    Full text: An increase of thyroid cancer incidence among children in Belarus has been observed after the Chernobyl accident. The main contributor to the thyroid dose was caused by 131 I intake with fresh milk in 1986. Other contributions to the thyroid dose (external gamma-exposure, short-lived iodine isotopes, internal radiocesium) were small in comparison to the dose from 131 I intakes soon after the accident. However, exposures to external radiation continued for a number of years after the accident. Thyroid doses from external gamma-exposure following the Chernobyl accident were mainly caused by gamma-exposure to 24 nuclides: 95 Zr, 95 Nb, 99 Mo, 99 mTc, 103 Ru, 103m Rh, 106 Ru, 125 Sb, 125m Te, 131m Te, 131 I, 132 Te, 132 I, 133 I, 135 I, 134 Cs, 136 Cs, 137 Cs, 140 Ba, 140 La, 141 Ce, 144 Ce, 144 Pr, 239 Np. Data of personal interview were used to take into account the personal residence history for the time elapsed from the Chernobyl accident until the interview (10 to 15 years later). Cumulative thyroid doses caused by external gamma-exposure during the passage of the radioactive cloud and from the ground contamination following the Chernobyl accident have been reconstructed. The median thyroid dose from external gamma-exposure to ∼11,770 cohort members of an epidemiological study was estimated to be ∼6 mGy. There are ∼3,400 persons with external dose estimates that exceed 20 mGy. Exposure from radionuclides deposited on the ground was the main source of external dose. The contribution from the passing radioactive cloud to external dose was found to be negligible. (author)

  9. External Validation of a Prediction Model for Successful External Cephalic Version

    NARCIS (Netherlands)

    de Hundt, Marcella; Vlemmix, Floortje; Kok, Marjolein; van der Steeg, Jan W.; Bais, Joke M.; Mol, Ben W.; van der Post, Joris A.

    2012-01-01

    We sought external validation of a prediction model for the probability of a successful external cephalic version (ECV). We evaluated the performance of the prediction model with calibration and discrimination. For clinical practice, we developed a score chart to calculate the probability of a

  10. External exposure from gamma radiation in uranium mines

    International Nuclear Information System (INIS)

    Thomson, J.E.

    1982-01-01

    Radiation doses received by workers in a high ore grade uranium mine are compared to those of other radiation workers and the need to be able to calculate the exposure rate from an ore body is indicated. The uranium-238 decay chain is presented and particular reference is made to the main gamma emitters and secular equilibrium of the members of the chain. Difficulties in dealing with a self attenuating volume source, in which scattering is important, are pointed out and traditional methods of solution are mentioned. It is shown that in the special case of an infinite ore body a simple solution may be obtained using the energy conservation principle. A straightforward method for calculating the exposure rate from an arbitrarily shaped ore body is given and corrections due to air attenuation, different soil types and possible lack of secular equilibrium are dealt with. The gamma ray spectrum from the ore is discussed with specific reference to the selection of suitable exposure monitors and the calculation of transmission through shields

  11. Fertility of women after exposure to internal and external radiation

    International Nuclear Information System (INIS)

    Polednak, A.P.

    1980-01-01

    Fertility was examined in 199 women exposed to internal and external radiation while employed in the radium watch-dial painting industry in Illinois between 1916 and 1929. In women with at least one live birth, mean log live-birth rate was significantly lower in the highest (estimated) ovarian-dose group than in the lowest group. In multiple regression analysis, intake dose but not duration of employment was a statistically significant predictor of log live-birth rate. There was no evidence for an increase in fetal deaths with increasing ovarian dose level (rem). This suggests that the findings on live-birth rate may not involve post-implantation dominant lethal mutations, but preimplantation losses could not be evaluated. Some possible explanations for these findings are discussed

  12. ExternE transport methodology for external cost evaluation of air pollution

    DEFF Research Database (Denmark)

    Jensen, S. S.; Berkowicz, R.; Brandt, J.

    The report describes how the human exposure estimates based on NERI's human exposure modelling system (AirGIS) can improve the Danish data used for exposure factors in the ExternE Transport methodology. Initially, a brief description of the ExternE Tranport methodology is given and it is summarised...

  13. Delayed effects of external radiation exposure: A brief history

    International Nuclear Information System (INIS)

    Miller, R.W.

    1995-01-01

    Within months of Roentgen's discovery of X rays, severe adverse effects were reported, but not well publicized. As a result, over the next two decades, fluoroscope operators suffered lethal skin carcinomas. Later, case reports appeared concerning leukemia in radiation workers, and infants born with severe mental retardation after their mothers had been given pelvic radiotherapy early in pregnancy. Fluoroscopy and radiotherapy for benign disorders continued to be used with abandon until authoritative reports were published on the adverse effects of ionizing radiation by the U.S. NAS-NRC and the UK MRC in 1956. Meanwhile, exposure to the atomic bombs in Japan had occurred and epidemics of delayed effects began to be recognized among the survivors: cataracts, leukemia and severe mental retardation among newborn infants after intra-uterine exposure. No statistically significant excess of germ-cell genetic effects was detected by six clinical measurements, the F 1 mortality, cytogenetic studies or biochemical genetic studies. Somatic cell effects were revealed by long-lasting chromosomal aberrations in peripheral lymphocytes, and somatic cell mutations were found at the glycophorin A locus in erythrocytes. Molecular biology is a likely focus of new studies based on the function of the gene for ataxia telangiectasia, a disorder in which children have severe, even lethal acute radiation reactions when given conventional doses of radiotherapy for lymphoma, to which they are prone. The tumor registries in Hiroshima and Nagasaki now provide incidence data that show the extent of increases in eight common cancers and no increase in eight others. The possibility of very late effects of A-bomb exposure is suggested by recent reports of increased frequencies of hyperparathyroidism, parathyroid cancers and certain causes of death other than cancer. 88 refs., 1 fig

  14. Evaluation of internal/external exposure from interior building materials

    International Nuclear Information System (INIS)

    Furuta, Etsuko; Morita-Murase, Yuko; Yoshizawa, Yukio

    2008-01-01

    Internal exposure to alpha particles emitted from 222 Rn (radon) and its daughters is the second leading cause of lung cancer. As a source of indoor radon in home, there are interior building materials that contain radioactive minerals. These radioactive consumer products have been claimed by distributors to have effect of 'minus-ion' or 'radon spring' for healthy promotion. We analyzed radioactive nuclides contained in the interior building materials, and measured radon levels released from them. The results of gamma-ray spectrometry revealed that these interior building materials contain U- and Th-series nuclides. The densities of some radioactive nuclides in the tile used for a bathroom exceeded the exempt limits of International Basic Safety Standards. However, the radon densities released from the tile was lower than detectable limit. In contrast, one of the wallpaper released 34 Bq·m -3 of radon gas in a 50-liter container. This value is two times higher than the average radon level in Japanese homes. The minus-ion effect' wallpapers are thought to be a cause of residential exposure to radon. (author)

  15. Patterns of poverty exposure and children's trajectories of externalizing and internalizing behaviors.

    Science.gov (United States)

    Comeau, Jinette; Boyle, Michael H

    2018-04-01

    Using data from the Child Supplement of the National Longitudinal Survey of Youth, we compare trajectories of externalizing and internalizing behaviors among children exposed to five patterns of poverty from birth to age 14: always or never poor - stable patterns; a single transition into or out of poverty, or repeated fluctuations in and out of poverty - changing patterns. We also examine how low maternal education and single parenthood interact with these poverty exposures to compound their adverse effects. Finally, we compare the magnitude of effects associated with the patterns of poverty exposure, as well as their interactions with low maternal education and single parenthood, on trajectories of externalizing and internalizing behaviors to determine if they are significantly different. Results reveal that initial levels and rates of change in children's trajectories of externalizing and internalizing behaviors are similar across the three changing patterns of poverty exposure, leading us to combine them into a single group representing intermittent poverty. Initial disparities between children who are never poor and their counterparts who are always or intermittently poor are constant over time for internalizing behaviors and grow in magnitude for externalizing behaviors. The cumulative negative effect of poverty exposure over time is stronger for externalizing vs. internalizing behaviors. Low maternal education compounds the adverse effects of persistent poverty, an effect that is similar for externalizing and internalizing behaviors.

  16. External exposure estimates for individuals near the Nevada Test Site

    International Nuclear Information System (INIS)

    Henderson, R.W.; Smale, R.F.

    1987-01-01

    Individuals living near the Nevada Test Site were exposed to both beta and gamma radiations from fission products and activation products resulting from the atmospheric testing of nuclear devices. These exposures were functions of the amount of material deposited, the time of arrival of the debris, and the amount of shielding afforded by structures. Results are presented for each of nine generic life styles. These are representative of the living patterns of the people residing in the area. For each event at each location for which data exist, a representative of each life style was closely followed for a period of thirty days. The results of these detailed calculations are then extrapolated to the present. 7 refs., 5 figs., 2 tabs

  17. Assessment of occupational exposures to external radiation - IAEA recommendation 1995

    Energy Technology Data Exchange (ETDEWEB)

    Trousil, J; Plichta, J [CSOD, Praha (Czech Republic); Nikodemova, D [SOD, Bratislava (Slovakia)

    1996-12-31

    The IAEA recommendation contains the guidance on: (1) establishing monitoring programmes; (2) the interpretation of results; (3) records keeping; (4) quality assurance. The objectives for workplace monitoring including the recommended methods are also involved. The choice of personal dosemeter depends not only on the type of radiation but also on the method of interpretation what will be used: (1) photon dosemeters giving information only on the personal dose equivalent Hp(10) - mostly TL or RPL dosemeters are used; (2) photon dosemeter of discriminating type giving, in addition to Hp(10) and Hp(0.07), some indication of radiation type and effective energy and detection of electrons - data which must be known for E calculation -mostly film badge is used; (3) extremity dosemeters giving information on Hp(0.07) - mostly TL dosemeters are used; (4) neutron dosemeters giving information on Hp(10) -track-etch or albedo dosemeters are used. The monitoring service should have quality assurance testing which is an organization`s internal system of procedures and practices which assures the quality of its service. This process may be part of the approval performance testing which is a part of approved procedures carried out be the authoritative organization in regular intervals. The approved monitoring service should perform the dose records keeping which serve the protection of the workers and these data are the part of the Register of the Professional Exposures which is mostly organized by the authoritative body. (J.K.).

  18. Assessment of occupational exposures to external radiation - IAEA recommendation 1995

    International Nuclear Information System (INIS)

    Trousil, J.; Plichta, J.; Nikodemova, D.

    1995-01-01

    The IAEA recommendation contains the guidance on: (1) establishing monitoring programmes; (2) the interpretation of results; (3) records keeping; (4) quality assurance. The objectives for workplace monitoring including the recommended methods are also involved. The choice of personal dosemeter depends not only on the type of radiation but also on the method of interpretation what will be used: (1) photon dosemeters giving information only on the personal dose equivalent Hp(10) - mostly TL or RPL dosemeters are used; (2) photon dosemeter of discriminating type giving, in addition to Hp(10) and Hp(0.07), some indication of radiation type and effective energy and detection of electrons - data which must be known for E calculation -mostly film badge is used; (3) extremity dosemeters giving information on Hp(0.07) - mostly TL dosemeters are used; (4) neutron dosemeters giving information on Hp(10) -track-etch or albedo dosemeters are used. The monitoring service should have quality assurance testing which is an organization's internal system of procedures and practices which assures the quality of its service. This process may be part of the approval performance testing which is a part of approved procedures carried out be the authoritative organization in regular intervals. The approved monitoring service should perform the dose records keeping which serve the protection of the workers and these data are the part of the Register of the Professional Exposures which is mostly organized by the authoritative body. (J.K.)

  19. Historical estimates of external gamma exposure and collective external gamma exposure from testing at the Nevada Test Site. II. Test series after Hardtack II, 1958, and summary

    International Nuclear Information System (INIS)

    Anspaugh, L.R.; Ricker, Y.E.; Black, S.C.; Grossman, R.F.; Wheeler, D.L.; Church, B.W.; Quinn, V.E.

    1990-01-01

    The historical data on the cumulative individual external gamma exposures are tabulated for communities around the Nevada Test Site for the time periods of 1961 to the signing of the Limited Test Ban Treaty on 5 August 1963, and from then until 1975. The collective exposures during the two time periods are calculated to be 610 and 320 person-R, respectively. The total collective external gamma exposure from 1951 through 1975 for these communities s calculated to be 86,000 person-R. The area considered includes the countries of Clark, Lincoln, Nye, and White Pine in Nevada and the countries of Iron and Washington in Utah; inclusion of Salt Lake City would have substantially increased the calculated collective exposure because of the large population. The methods of calculation are reviewed. Also, the historical data on the assessment of dose via ingestion are reviewed with emphasis on the dose to the thyroid of infants living in St. George, UT, at the time of fallout from event HARRY on 19 May 1953

  20. Carcinogenesis--a synopsis of human experience with external exposure in medicine

    International Nuclear Information System (INIS)

    Boice, J.D. Jr.

    1988-01-01

    Studies in the 1980s of medically irradiated populations have increased our knowledge of radiation carcinogenesis. (1) Investigations of prenatal x-ray exposures, especially in twins, provide evidence that very low doses of ionizing radiation may cause cancer in humans. (2) Fractionated doses appear as effective as single exposures of the same total dose in causing breast cancer, but seem less effective for lung cancer. (3) Excess breast cancers can occur among women exposed under age 10, indicating that the immature breast is susceptible to the carcinogenic action of radiation. (4) Moderate doses on the order of 1 Gy to the brains of children can cause tumors later in life; moderately high doses to the skin can cause cancer when followed by frequent exposure to ultraviolet light. (5) Radiotherapy for cervical cancer can increase the rate of subsequent leukemia with the best fitting dose-response functions including a negative exponential term to account for cell-killing. (6) Low-dose exposures of about 10 cGy may increase the risk of thyroid cancer. (7) Second cancers following radiotherapy for a variety of cancers occur primarily among long-term survivors. (8) Radiotherapy may not significantly increase the risk of leukemia following childhood cancer, whereas chemotherapy with alkylating agents is a major risk factor. (9) Bone cancer occurs after high-dose radiotherapy for childhood cancer, but children with retinoblastoma are not more susceptible to radiation-induced disease than children with other malignancies. (10) High-dose external beam therapy can cause thyroid cancer. (11) Studies of cervical cancer patients indicate that the risk of radiation-induced second malignancies follows a time-response model consistent with a constant multiplication of the underlying background incidence. 83 references

  1. Evaluation of dose conversion coefficients for external exposure using Taiwanese reference man and woman

    International Nuclear Information System (INIS)

    Chang, S.J.; Hung, S.Y.; Liu, Y.L.; Jiang, S.H.; Wu, J.

    2015-01-01

    Reference man has been widely used for external and internal dose evaluation of radiation protection. The parameters of the mathematical model of organs suggested by the International Commission of Radiological Protection (ICRP) are adopted from the average data of Caucasians. However, the organ masses of Asians are significantly different from the data of Caucasians, leading to potentially dosimetric errors. In this study, a total of 40 volunteers whose heights and weights corresponded to the statistical average of Taiwanese adults were recruited. Magnetic resonance imaging was performed, and T2-weighted images were acquired. The Taiwanese reference man and woman were constructed according to the measured organ masses. The dose conversion coefficients (DCFs) for anterior-posterior (AP), posterior-anterior (PA), right lateral (RLAT) and left lateral (LLAT) irradiation geometries were simulated. For the Taiwanese reference man, the average differences of the DCFs compared with the results of ICRP-74 were 7.6, 5.1 and 11.1 % for 0.1, 1 and 10 MeV photons irradiated in the AP direction. The maximum difference reached 51.7 % for the testes irradiated by 10 MeV photons. The size of the trunk, the volume and the geometric position of organs can cause a significant impact on the DCFs for external exposure of radiation. The constructed Taiwanese reference man and woman can be used in radiation protection to increase the accuracy of dose evaluation for the Taiwanese population. (authors)

  2. External exposure doses due to gamma emitting natural radionuclides in some Egyptian building materials.

    Science.gov (United States)

    Moharram, B M; Suliman, M N; Zahran, N F; Shennawy, S E; El Sayed, A R

    2012-01-01

    Using of building materials containing naturally occurring radionuclides as (238)U, (232)Th and (40)K and their progeny results in an external exposures of the housing of such buildings. In the present study, indoor dose rates for typical Egyptian rooms are calculated using the analytical method and activity concentrations of natural radionuclides in some building materials. Uniform chemical composition of the walls, floor and ceiling as well as uniform mass concentrations of the radionuclides in walls, floor and ceiling assumed. Different room models are assumed to discuss variation of indoor dose rates according to variation in room construction. Activity concentrations of (238)U, (232)Th and (40)K content in eight samples representative Clay soil and different building materials used in most recent Egyptian building were measured using Inductively Coupled Plasma-Mass Spectrometry (ICP-MS). The specific activity for (238)U, (232)Th and (40)K, from the selected samples, were in the range 14.15-60.64, 2.75-84.66 and 7.35-554.4Bqkg(-1), respectively. The average indoor absorbed dose rates in air ranged from 0.005μGyh(-1) to 0.071μGyh(-1) and the corresponding population-weighted annual effective dose due to external gamma radiation varies from 0.025 to 0.345mSv. An outdoor dose rate for typical building samples in addition to some radiological hazards has been introduced for comparison. Copyright © 2011 Elsevier Ltd. All rights reserved.

  3. New model for mines and transportation tunnels external dose calculation using Monte Carlo simulation

    International Nuclear Information System (INIS)

    Allam, Kh. A.

    2017-01-01

    In this work, a new methodology is developed based on Monte Carlo simulation for tunnels and mines external dose calculation. Tunnels external dose evaluation model of a cylindrical shape of finite thickness with an entrance and with or without exit. A photon transportation model was applied for exposure dose calculations. A new software based on Monte Carlo solution was designed and programmed using Delphi programming language. The variation of external dose due to radioactive nuclei in a mine tunnel and the corresponding experimental data lies in the range 7.3 19.9%. The variation of specific external dose rate with position in, tunnel building material density and composition were studied. The given new model has more flexible for real external dose in any cylindrical tunnel structure calculations. (authors)

  4. Modeled population exposures to ozone

    Data.gov (United States)

    U.S. Environmental Protection Agency — Population exposures to ozone from APEX modeling for combinations of potential future air quality and demographic change scenarios. This dataset is not publicly...

  5. Mortality from internal and external radiation exposure in a cohort of male German uranium millers, 1946-2008

    Energy Technology Data Exchange (ETDEWEB)

    Kreuzer, M.; Dufey, F.; Schnelzer, M.; Sogl, M.; Walsh, L. [Federal Office for Radiation Protection, Neuherberg (Germany). Dept. of Radiation Protection and Health; Laurier, D. [Institute for Radiological Protection and Nuclear Safety (IRSN), Paris (France); Nowak, D. [LMU Muenchen (Germany). Inst. for Occupational Medicine and Environmental Medicine; Marsh, J.W. [Public Health England, Chilton, Didcot (United Kingdom)

    2015-05-15

    To examine exposure-response relationships between ionizing radiation and several mortality outcomes in a subgroup of 4,054 men of the German uranium miner cohort study, who worked between 1946 and 1989 in milling facilities, but never underground or in open pit mines. Mortality follow-up was from 1946 to 2008, accumulating 158,383 person-years at risk. Cumulative exposure to radon progeny in working level months (WLM) (mean = 8, max = 127), long-lived radionuclides from uranium ore dust in kBqh/m{sup 3} (mean = 3.9, max = 132), external gamma radiation in mSv (mean = 26, max = 667) and silica dust was estimated by a comprehensive job-exposure matrix. Internal Poisson regression models were applied to estimate the linear excess relative risk (ERR) per unit of cumulative exposure. Overall, a total of 457, 717 and 111 deaths occurred from malignant cancer, cardiovascular diseases and non-malignant respiratory diseases, respectively. Uranium ore dust and silica dust were not associated with mortality from any of these disease groups. A statistically significant relationship between cumulative radon exposure and mortality from all cancers (ERR/100 WLM = 1.71; p = 0.02), primarily due to lung cancer (n = 159; ERR/100 WLM = 3.39; p = 0.05), was found. With respect to cumulative external gamma radiation, an excess of mortality of solid cancers (n = 434; ERR/Sv = 1.86; p = 0.06), primarily due to stomach cancer (n = 49, ERR/Sv = 10.0; p = 0.12), was present. The present findings show an excess mortality from lung cancer due to radon exposure and from solid cancers due to external gamma radiation in uranium millers that was not statistically significant. Exposure to uranium was not associated with any cause of death, but absorbed organ doses were estimated to be low.

  6. Mortality from internal and external radiation exposure in a cohort of male German uranium millers, 1946-2008

    International Nuclear Information System (INIS)

    Kreuzer, M.; Dufey, F.; Schnelzer, M.; Sogl, M.; Walsh, L.; Nowak, D.

    2015-01-01

    To examine exposure-response relationships between ionizing radiation and several mortality outcomes in a subgroup of 4,054 men of the German uranium miner cohort study, who worked between 1946 and 1989 in milling facilities, but never underground or in open pit mines. Mortality follow-up was from 1946 to 2008, accumulating 158,383 person-years at risk. Cumulative exposure to radon progeny in working level months (WLM) (mean = 8, max = 127), long-lived radionuclides from uranium ore dust in kBqh/m 3 (mean = 3.9, max = 132), external gamma radiation in mSv (mean = 26, max = 667) and silica dust was estimated by a comprehensive job-exposure matrix. Internal Poisson regression models were applied to estimate the linear excess relative risk (ERR) per unit of cumulative exposure. Overall, a total of 457, 717 and 111 deaths occurred from malignant cancer, cardiovascular diseases and non-malignant respiratory diseases, respectively. Uranium ore dust and silica dust were not associated with mortality from any of these disease groups. A statistically significant relationship between cumulative radon exposure and mortality from all cancers (ERR/100 WLM = 1.71; p = 0.02), primarily due to lung cancer (n = 159; ERR/100 WLM = 3.39; p = 0.05), was found. With respect to cumulative external gamma radiation, an excess of mortality of solid cancers (n = 434; ERR/Sv = 1.86; p = 0.06), primarily due to stomach cancer (n = 49, ERR/Sv = 10.0; p = 0.12), was present. The present findings show an excess mortality from lung cancer due to radon exposure and from solid cancers due to external gamma radiation in uranium millers that was not statistically significant. Exposure to uranium was not associated with any cause of death, but absorbed organ doses were estimated to be low.

  7. The U(1) Higgs model in an external electromagnetic field

    International Nuclear Information System (INIS)

    Damgaard, P.H.; Heller, U.M.

    1988-01-01

    An external electromagnetic field is coupled to the lattice-regularized U(1) Higgs model. We study the phase diagram of this model by both analytical and numerical techniques for different values of the external field strength tensor. The results are compared with expectations based on the analogy with superconducting systems, as described by the phenomenological Ginzburg-Landau theory. (orig.)

  8. Assessment of occupational exposure due to external sources of radiation. Safety guide

    International Nuclear Information System (INIS)

    2000-01-01

    Occupational exposure to ionizing radiation can occur in a range of industries, medical institutions, educational and research establishments and nuclear fuel cycle facilities. Adequate radiation protection of workers is essential for the safe and acceptable use of radiation, radioactive materials and nuclear energy. The three Safety Guides on occupational radiation protection are jointly sponsored by the IAEA and the International Labour Office. The Agency gratefully acknowledges the contribution of the European Commission to the development of the present Safety Guide. The present Safety Guide addresses the assessment of exposure due to external sources of radiation in the workplace. Such exposure can result from a number of sources within a workplace, and the monitoring of workers and the workplace in such situations is an integral part of any occupational radiation protection programme. The assessment of exposure due to external radiation sources depends critically upon knowledge of the radiation type and energy and the conditions of exposure. The present Safety Guide reflects the major changes over the past decade in international practice in external dose assessment

  9. Assessment of occupational exposure due to external sources of radiation. Safety guide

    International Nuclear Information System (INIS)

    2004-01-01

    Occupational exposure to ionizing radiation can occur in a range of industries, medical institutions, educational and research establishments and nuclear fuel cycle facilities. Adequate radiation protection of workers is essential for the safe and acceptable use of radiation, radioactive materials and nuclear energy. The three Safety Guides on occupational radiation protection are jointly sponsored by the IAEA and the International Labour Office. The Agency gratefully acknowledges the contribution of the European Commission to the development of the present Safety Guide. The present Safety Guide addresses the assessment of exposure due to external sources of radiation in the workplace. Such exposure can result from a number of sources within a workplace, and the monitoring of workers and the workplace in such situations is an integral part of any occupational radiation protection programme. The assessment of exposure due to external radiation sources depends critically upon knowledge of the radiation type and energy and the conditions of exposure. The present Safety Guide reflects the major changes over the past decade in international practice in external dose assessment

  10. Assessment of occupational exposure due to external sources of radiation. Safety guide

    International Nuclear Information System (INIS)

    1999-01-01

    Occupational exposure to ionizing radiation can occur in a range of industries, medical institutions, educational and research establishments and nuclear fuel cycle facilities. Adequate radiation protection of workers is essential for the safe and acceptable use of radiation, radioactive materials and nuclear energy. The three Safety Guides on occupational radiation protection are jointly sponsored by the IAEA and the International Labour Office. The Agency gratefully acknowledges the contribution of the European Commission to the development of the present Safety Guide. The present Safety Guide addresses the assessment of exposure due to external sources of radiation in the workplace. Such exposure can result from a number of sources within a workplace, and the monitoring of workers and the workplace in such situations is an integral part of any occupational radiation protection programme. The assessment of exposure due to external radiation sources depends critically upon knowledge of the radiation type and energy and the conditions of exposure. The present Safety Guide reflects the major changes over the past decade in international practice in external dose assessment

  11. Accidents and incidents with external and/or internal radiation-exposure

    International Nuclear Information System (INIS)

    Anon.

    1990-01-01

    An individual radiation exposure accident is an unexpected and unintended event which gives rise to an overexposure (external or internal). By overexposure one means all external or internal exposure which could lead to the exceeding of the regulatory norms. Going beyond these limits does not always produce pathological manifestations. The term radiological accident is, in practice, used only when there is an occurrence of some biological or clinical response, or when some therapeutic action is required. A radio-exposure accident can occur: within or from a nuclear power plant or from a center employing ionizing radiation. These are the most frequent; and during the transport of radioactive materials. These are exceptional events. The tanks and containers used in the transport of highly radioactive substances are exhaustively studied for their resistance to accidents, and the conditions of transport determined by very strict national and international regulations. The transport of substances of low radioactivity (labelled molecules, radiopharmaceuticals...) carries only minor risks

  12. Assessment of internal and external exposure to ionizing radiation in laboratories of nuclear medicine and radiotherapy

    International Nuclear Information System (INIS)

    Adamiak-Ziemba, J.; Doniec, J.; Kocznow, W.; Hawrynski, M.

    1985-01-01

    The investigations with determination of radioisotopes in urine led to detection of contamination with 99m Tc and radioactive iodine. The measurements and dosimetry of external radiation demonstrated that workers in laboratories of radioisotope diagnosis received a mean annual equivalent doses amounted less than 5% of the permissible dose for persons with occupational exposure. It was also established that external exposure was mainly responsible for this. The data about the levels of internal exposure in laboratories of nuclear medicine and radiotherapy demonstrated that introduction of a permanent central system of control of internal contamination of workers would be useless since the observation of the already accepted principles of radiological protection is sufficient for avoiding contamination. (author)

  13. Transfer shuttle for vitrified residue canisters control of risks associated with external exposure and heat release

    Energy Technology Data Exchange (ETDEWEB)

    BIndel, L.; Gamess, A.; Lejeune, E.; Cellier, P.; Maillard, A. [SGN Reseau Eurisys, 78 - Saint Quentin (France)

    1998-07-01

    In the La Hague COGEMA's plant area, nuclear residue isolated by reprocessing are transported by means of specific transfer shuttles between the different processing and/or conditioning facilities and the storage ones. These shuttles are designed by reference to the applicable dose equivalent rate (DER) limits for transport on the site and the thermal behavior limitations of certain mechanical components which guarantee the containment of the transported waste. This paper describes and example of a study conducted on a transfer shuttle for vitrified residue canisters. Concerning the control of risks associated with external exposure and with heat releases, these were handled by the 'Shielding-Criticality-Dispersion' and 'process Modelling and Simulation' Sections of the Technical Division of SGN. The dose profiles around the shuttle, as a function of the shielding heterogeneities and possible radiation leakage, as well as the thermal fields within the shuttle, were calculated using 3D models. These design studies ultimately helped to select and validate the optimal solutions. (authors)

  14. Human internal and external exposure to PBDEs--a review of levels and sources

    DEFF Research Database (Denmark)

    Frederiksen, Marie; Vorkamp, Katrin; Thomsen, Marianne

    2009-01-01

    This paper reviews the existing literature on human exposure to polybrominated diphenyl ethers (PBDEs), with particular focus on external exposure routes (e.g. dust, diet, and air) and the resulting internal exposure to PBDEs (e.g. breast milk and blood). Being lipophilic and persistent organic...... ingest more dust than adults. Infants are also exposed to PBDEs via breast milk. Internal human exposure has generally been found to be one order of magnitude larger in North America than in Europe and Asia. These differences cannot solely be explained by the dietary intake as meat products are the only...... food group where some differences has been observed. However, indoor air and dust concentrations have been found to be approximately one order of magnitude higher in North America than in Europe, possibly a result of different fire safety standards. Within Europe, higher PBDE concentrations in dust...

  15. Severe deterministic effects of external exposure and intake of radioactive material: basis for emergency response criteria

    International Nuclear Information System (INIS)

    Kutkov, V; Buglova, E; McKenna, T

    2011-01-01

    Lessons learned from responses to past events have shown that more guidance is needed for the response to radiation emergencies (in this context, a 'radiation emergency' means the same as a 'nuclear or radiological emergency') which could lead to severe deterministic effects. The International Atomic Energy Agency (IAEA) requirements for preparedness and response for a radiation emergency, inter alia, require that arrangements shall be made to prevent, to a practicable extent, severe deterministic effects and to provide the appropriate specialised treatment for these effects. These requirements apply to all exposure pathways, both internal and external, and all reasonable scenarios, to include those resulting from malicious acts (e.g. dirty bombs). This paper briefly describes the approach used to develop the basis for emergency response criteria for protective actions to prevent severe deterministic effects in the case of external exposure and intake of radioactive material.

  16. External validation of EPIWIN biodegradation models.

    Science.gov (United States)

    Posthumus, R; Traas, T P; Peijnenburg, W J G M; Hulzebos, E M

    2005-01-01

    The BIOWIN biodegradation models were evaluated for their suitability for regulatory purposes. BIOWIN includes the linear and non-linear BIODEG and MITI models for estimating the probability of rapid aerobic biodegradation and an expert survey model for primary and ultimate biodegradation estimation. Experimental biodegradation data for 110 newly notified substances were compared with the estimations of the different models. The models were applied separately and in combinations to determine which model(s) showed the best performance. The results of this study were compared with the results of other validation studies and other biodegradation models. The BIOWIN models predict not-readily biodegradable substances with high accuracy in contrast to ready biodegradability. In view of the high environmental concern of persistent chemicals and in view of the large number of not-readily biodegradable chemicals compared to the readily ones, a model is preferred that gives a minimum of false positives without a corresponding high percentage false negatives. A combination of the BIOWIN models (BIOWIN2 or BIOWIN6) showed the highest predictive value for not-readily biodegradability. However, the highest score for overall predictivity with lowest percentage false predictions was achieved by applying BIOWIN3 (pass level 2.75) and BIOWIN6.

  17. Patterns of poverty exposure and children’s trajectories of externalizing and internalizing behaviors

    OpenAIRE

    Comeau, Jinette; Boyle, Michael H.

    2017-01-01

    Using data from the Child Supplement of the National Longitudinal Survey of Youth, we compare trajectories of externalizing and internalizing behaviors among children exposed to five patterns of poverty from birth to age 14: always or never poor – stable patterns; a single transition into or out of poverty, or repeated fluctuations in and out of poverty – changing patterns. We also examine how low maternal education and single parenthood interact with these poverty exposures to compound their...

  18. Externalizing Behaviour for Analysing System Models

    DEFF Research Database (Denmark)

    Ivanova, Marieta Georgieva; Probst, Christian W.; Hansen, René Rydhof

    2013-01-01

    System models have recently been introduced to model organisations and evaluate their vulnerability to threats and especially insider threats. Especially for the latter these models are very suitable, since insiders can be assumed to have more knowledge about the attacked organisation than outside...... attackers. Therefore, many attacks are considerably easier to be performed for insiders than for outsiders. However, current models do not support explicit specification of different behaviours. Instead, behaviour is deeply embedded in the analyses supported by the models, meaning that it is a complex......, if not impossible task to change behaviours. Especially when considering social engineering or the human factor in general, the ability to use different kinds of behaviours is essential. In this work we present an approach to make the behaviour a separate component in system models, and explore how to integrate...

  19. Pollution externalities in a Schumpeterian growth model

    OpenAIRE

    Koesler, Simon

    2010-01-01

    This paper extends a standard Schumpeterian growth model to include an environmental dimension. Thereby, it explicitly links the pollution intensity of economic activity to technological progress. In a second step, it investigates the effect of pollution on economic growth under the assumption that pollution intensities are related to technological progress. Several conclusions emerge from the model. In equilibrium, the economy follows a balanced growth path. The effect of pollution on the ec...

  20. Analysis of radioactivity increase of rad waste filled in fibre-reinforced concrete container regarding external exposure of workers

    International Nuclear Information System (INIS)

    Baratova, D.; Hrncir, T.; Necas, V.

    2012-01-01

    The paper deals with the assessment of the external radiation exposure of workers performing the individual tasks associated with disposal of the fibre-reinforced concrete containers in the National Radioactive Waste Repository in Mochovce. Models for fibre-reinforced concrete containers with maximum activity allowable for transport and for fibre-reinforced concrete containers contained radionuclides at the common level of activity concentration were created in order to analyze the option of fibre-reinforced concrete containers radioactivity increase. Calculations of individual effective doses have been carried out for three workers who work in the control area of the waste disposal facility dosimetrist, assistant and crane worker. (Authors)

  1. Advancing environmental toxicology through chemical dosimetry: External exposures versus tissue residues

    Science.gov (United States)

    McCarty, L.S.; Landrum, P.F.; Luoma, S.N.; Meador, J.P.; Merten, A.A.; Shephard, B.K.; van Wezelzz, A.P.

    2011-01-01

    The tissue residue dose concept has been used, although in a limited manner, in environmental toxicology for more than 100 y. This review outlines the history of this approach and the technical background for organic chemicals and metals. Although the toxicity of both can be explained in tissue residue terms, the relationship between external exposure concentration, body and/or tissues dose surrogates, and the effective internal dose at the sites of toxic action tends to be more complex for metals. Various issues and current limitations related to research and regulatory applications are also examined. It is clear that the tissue residue approach (TRA) should be an integral component in future efforts to enhance the generation, understanding, and utility of toxicity testing data, both in the laboratory and in the field. To accomplish these goals, several key areas need to be addressed: 1) development of a risk-based interpretive framework linking toxicology and ecology at multiple levels of biological organization and incorporating organism-based dose metrics; 2) a broadly applicable, generally accepted classification scheme for modes/mechanisms of toxic action with explicit consideration of residue information to improve both single chemical and mixture toxicity data interpretation and regulatory risk assessment; 3) toxicity testing protocols updated to ensure collection of adequate residue information, along with toxicokinetics and toxicodynamics information, based on explicitly defined toxicological models accompanied by toxicological model validation; 4) continued development of residueeffect databases is needed ensure their ongoing utility; and 5) regulatory guidance incorporating residue-based testing and interpretation approaches, essential in various jurisdictions. ??:2010 SETAC.

  2. Individual external exposures from Nevada Test Site fallout for Utah leukemia cases and controls

    International Nuclear Information System (INIS)

    Lloyd, R.D.; Gren, D.C.; Simon, S.L.; Wrenn, M.E.; Hawthorne, H.A.; Lotz, T.M.; Stevens, W.; Till, J.E.

    1990-01-01

    External gamma-ray exposures from fallout originating at the Nevada Test Site (NTS) have been assigned to 6,507 individual subjects (1,177 leukemia cases and 5,330 control subjects) who died as Utah residents between 1952 and 1981. Leukemia cases were identified, confirmed, and classified by cell type from the Utah Cancer Registry, Utah State vital records, and medical records. Residential histories were obtained from the Deceased Membership File (DMF) of the Church of Jesus Christ of Latter-day Saints (LDS), supplemented by information from the LDS Church Census Records that were taken in 1950, 1955, and 1960-62. Control subjects were selected randomly within age strata from the DMF and were frequency-matched to the cases by age at death and for sex. Individual radiation exposures were assigned as a function of residence location and time interval for each residence during the fallout period (1951-1958) using geographic exposure data taken from the literature. Temporal distribution of exposure for subjects who resided in more than one locality or who were born or died during the fallout period was determined from data of other investigators. Calculated gamma-ray exposures for each place of residence were summed for each subject to yield the exposure to fallout from the NTS

  3. Development of a external exposure computational model for studying of input dose in skin for radiographs of thorax and vertebral column; Desenvolvimento de um modelo computacional de exposicao externa para estudo da dose de entrada na pele para radiografias de torax e coluna

    Energy Technology Data Exchange (ETDEWEB)

    Muniz, Bianca C.; Menezes, Claudio J.M., E-mail: bianca.cm95@gmail.com, E-mail: cjmm@cnen.gov.br [Centro Regional de Ciencias Nucleares do Nordeste (CRCN-NE/CNEN-PE), Recife, PE (Brazil); Vieira, Jose W., E-mail: jwvieira@br.inter.net [Instituto Federal de Educacao, Ciencia e Tecnologia de Pernambuco (IFPE), Recife, PE (Brazil)

    2014-07-01

    The dosimetric measurements do not always happen directly in the human body. Therefore, these assessments can be performed using anthropomorphic models (phantoms) evidencing models computational exposure (MCE) using techniques of Monte Carlo Method for virtual simulations. These processing techniques coupled with more powerful and affordable computers make the Monte Carlo method one of the tools most used worldwide in radiation transport area. In this work, the Monte Carlo EGS4 program was used to develop a computer model of external exposure to study the entrance skin dose for chest and column X-radiography and, aiming to optimize these practices by reducing doses to patients, professionals involved and the general public. The results obtained experimentally with the electrometer Radcal, model 9015, associated with the ionization chamber for radiology model 10X5-6, showed that the proposed computational model can be used in quality assurance programs in radiodiagnostic, evaluating the entrance skin dose when varying parameters of the radiation beam such as kilo voltage peak (kVp), current-time product (mAs), total filtration and distance surface source (DFS), optimizing the practices in radiodiagnostic and meeting the current regulation.

  4. Application of declarative modeling approaches for external events

    International Nuclear Information System (INIS)

    Anoba, R.C.

    2005-01-01

    Probabilistic Safety Assessments (PSAs) are increasingly being used as a tool for supporting the acceptability of design, procurement, construction, operation, and maintenance activities at Nuclear Power Plants. Since the issuance of Generic Letter 88-20 and subsequent IPE/IPEEE assessments, the NRC has issued several Regulatory Guides such as RG 1.174 to describe the use of PSA in risk-informed regulation activities. Most PSA have the capability to address internal events including internal floods. As the more demands are being placed for using the PSA to support risk-informed applications, there has been a growing need to integrate other eternal events (Seismic, Fire, etc.) into the logic models. Most external events involve spatial dependencies and usually impact the logic models at the component level. Therefore, manual insertion of external events impacts into a complex integrated fault tree model may be too cumbersome for routine uses of the PSA. Within the past year, a declarative modeling approach has been developed to automate the injection of external events into the PSA. The intent of this paper is to introduce the concept of declarative modeling in the context of external event applications. A declarative modeling approach involves the definition of rules for injection of external event impacts into the fault tree logic. A software tool such as the EPRI's XInit program can be used to interpret the pre-defined rules and automatically inject external event elements into the PSA. The injection process can easily be repeated, as required, to address plant changes, sensitivity issues, changes in boundary conditions, etc. External event elements may include fire initiating events, seismic initiating events, seismic fragilities, fire-induced hot short events, special human failure events, etc. This approach has been applied at a number of US nuclear power plants including a nuclear power plant in Romania. (authors)

  5. Exposure of healthy subjects with emissions from a gas metal arc welding process: part 1--exposure technique and external exposure.

    Science.gov (United States)

    Brand, P; Havlicek, P; Steiners, M; Holzinger, K; Reisgen, U; Kraus, T; Gube, M

    2013-01-01

    Studies concerning welding fume-related adverse health effects in welders are hampered by the heterogeneity of workplace situations, resulting in complex and non-standardized exposure conditions. In order to carry out welding fume exposure studies under controlled and standardized conditions, the Aachen Workplace Simulation Laboratory was developed. This laboratory consists of an emission room, in which welding fume is produced, and an exposure room in which human subjects are exposed to these fumes. Both rooms are connected by a ventilation system which allows the welding fume concentration to be regulated. Particle mass concentration was measured with a TEOM microbalance and the particle number-size distribution using a Grimm SMPS device. In a study, which is the subject of this paper, it has been shown that welding fume concentration can easily be regulated between 1 and about 3 mg m(-3). The chosen concentration can be kept constant for more than 8 h. However, transport of the particles from the emission room into the exposure room leads to a change in particle size distribution, which is probably due to coagulation of the fraction of smallest particles. The Aachen Workplace Simulation Laboratory is suitable for controlled exposure studies with human subjects.

  6. Calculation of external exposure during transport and disposal of radioactive waste arisen from dismantling of steam generator

    International Nuclear Information System (INIS)

    Hornacek, M.; Necas, V.

    2014-01-01

    The dismantling of large components (reactor pressure vessel, reactor internals, steam generator) represents complex of processes involving preparation, dismantling, waste treatment and conditioning, transport and final disposal. To optimise all of these activities in accordance with the ALARA principle the prediction of the exposure of workers is an essential prerequisite. The paper deals with the calculation of external exposure of workers during transport and final disposal of heat exchange tubes of steam generator used in Slovak nuclear power plant V1 in Jaslovske Bohunice. The type of waste packages, the calculation models of truck and National Radioactive Waste Repository in Mochovce are presented. The detailed methodology of radioactive waste disposal is showed and the degree of influence of time decay (0, 5 and 10 years) on the radiological conditions during transport and disposal is studied. All of the results do not exceed the limits given in Slovak and international regulatory documents. (authors)

  7. Calculation of dose-rate conversion factors for external exposure to photons and electrons

    International Nuclear Information System (INIS)

    Kocher, D.C.

    1978-01-01

    Methods are presented for the calculation of dose-rate conversion factors for external exposure to photon and electron radiation from radioactive decay. A dose-rate conversion factor is defined as the dose-equivalent rate per unit radionuclide concentration. Exposure modes considered are immersion in contaminated air, immersion in contaminated water, and irradiation from a contaminated ground surface. For each radiation type and exposure mode, dose-rate conversion factors are derived for tissue-equivalent material at the body surface of an exposed individual. In addition, photon dose-rate conversion factors are estimated for 22 body organs. The calculations are based on the assumption that the exposure medium is infinite in extent and that the radionuclide concentration is uniform. The dose-rate conversion factors for immersion in contaminated air and water then follow from the requirement that all of the energy emitted in the radioactive decay is absorbed in the infinite medium. Dose-rate conversion factors for ground-surface exposure are calculated at a reference location above a smooth, infinite plane using the point-kernel integration method and known specific absorbed fractions for photons and electrons in air

  8. Thyroid Cancer after Childhood Exposure to External Radiation: An Updated Pooled Analysis of 12 Studies

    Science.gov (United States)

    Veiga, Lene H. S.; Holmberg, Erik; Anderson, Harald; Pottern, Linda; Sadetzki, Siegal; Adams, M. Jacob; Sakata, Ritsu; Schneider, Arthur B.; Inskip, Peter; Bhatti, Parveen; Johansson, Robert; Neta, Gila; Shore, Roy; de Vathaire, Florent; Damber, Lena; Kleinerman, Ruth; Hawkins, Michael M.; Tucker, Margaret; Lundell, Marie; Lubin, Jay H.

    2016-01-01

    Studies have causally linked external thyroid radiation exposure in childhood with thyroid cancer. In 1995, investigators conducted relative risk analyses of pooled data from seven epidemiologic studies. Doses were mostly 50 Gy. We pooled data from 12 studies of thyroid cancer patients who were exposed to radiation in childhood (ages <20 years), more than doubling the data, including 1,070 (927 exposed) thyroid cancers and 5.3 million (3.4 million exposed) person-years. Relative risks increased supralinearly through 2–4 Gy, leveled off between 10–30 Gy and declined thereafter, remaining significantly elevated above 50 Gy. There was a significant relative risk trend for doses <0.10 Gy (P < 0.01), with no departure from linearity (P = 0.36). We observed radiogenic effects for both papillary and nonpapillary tumors. Estimates of excess relative risk per Gy (ERR/Gy) were homogeneous by sex (P = 0.35) and number of radiation treatments (P = 0.84) and increased with decreasing age at the time of exposure. The ERR/Gy estimate was significant within ten years of radiation exposure, 2.76 (95% CI, 0.94–4.98), based on 42 exposed cases, and remained elevated 50 years and more after exposure. Finally, exposure to chemotherapy was significantly associated with thyroid cancer, with results supporting a nonsynergistic (additive) association with radiation. PMID:27128740

  9. Dynamic State Space Partitioning for External Memory Model Checking

    DEFF Research Database (Denmark)

    Evangelista, Sami; Kristensen, Lars Michael

    2009-01-01

    We describe a dynamic partitioning scheme usable by model checking techniques that divide the state space into partitions, such as most external memory and distributed model checking algorithms. The goal of the scheme is to reduce the number of transitions that link states belonging to different...

  10. Estimated dose rates to members of the public from external exposure to patients with {sup 131}I thyroid treatment

    Energy Technology Data Exchange (ETDEWEB)

    Dewji, S., E-mail: dewjisa@ornl.gov; Bellamy, M.; Leggett, R.; Eckerman, K. [Oak Ridge National Laboratory, 1 Bethel Valley Road, MS-6335, Oak Ridge, Tennessee 37831 (United States); Hertel, N. [Oak Ridge National Laboratory, 1 Bethel Valley Road, MS-6335, Oak Ridge, Tennessee 37831 and Georgia Institute of Technology, 770 State Street, Atlanta, Georgia 30332-0745 (United States); Sherbini, S.; Saba, M. [United States Nuclear Regulatory Commission, Washington, DC 20555-0001 (United States)

    2015-04-15

    Purpose: Estimated dose rates that may result from exposure to patients who had been administered iodine-131 ({sup 131}I) as part of medical therapy were calculated. These effective dose rate estimates were compared with simplified assumptions under United States Nuclear Regulatory Commission Regulatory Guide 8.39, which does not consider body tissue attenuation nor time-dependent redistribution and excretion of the administered {sup 131}I. Methods: Dose rates were estimated for members of the public potentially exposed to external irradiation from patients recently treated with {sup 131}I. Tissue attenuation and iodine biokinetics were considered in the patient in a larger comprehensive effort to improve external dose rate estimates. The external dose rate estimates are based on Monte Carlo simulations using the Phantom with Movable Arms and Legs (PIMAL), previously developed by Oak Ridge National Laboratory and the United States Nuclear Regulatory Commission. PIMAL was employed to model the relative positions of the {sup 131}I patient and members of the public in three exposure scenarios: (1) traveling on a bus in a total of six seated or standing permutations, (2) two nursing home cases where a caregiver is seated at 30 cm from the patient’s bedside and a nursing home resident seated 250 cm away from the patient in an adjacent bed, and (3) two hotel cases where the patient and a guest are in adjacent rooms with beds on opposite sides of the common wall, with the patient and guest both in bed and either seated back-to-back or lying head to head. The biokinetic model predictions of the retention and distribution of {sup 131}I in the patient assumed a single voiding of urinary bladder contents that occurred during the trip at 2, 4, or 8 h after {sup 131}I administration for the public transportation cases, continuous first-order voiding for the nursing home cases, and regular periodic voiding at 4, 8, or 12 h after administration for the hotel room cases. Organ

  11. Estimated dose rates to members of the public from external exposure to patients with 131I thyroid treatment

    International Nuclear Information System (INIS)

    Dewji, S.; Bellamy, M.; Leggett, R.; Eckerman, K.; Hertel, N.; Sherbini, S.; Saba, M.

    2015-01-01

    Purpose: Estimated dose rates that may result from exposure to patients who had been administered iodine-131 ( 131 I) as part of medical therapy were calculated. These effective dose rate estimates were compared with simplified assumptions under United States Nuclear Regulatory Commission Regulatory Guide 8.39, which does not consider body tissue attenuation nor time-dependent redistribution and excretion of the administered 131 I. Methods: Dose rates were estimated for members of the public potentially exposed to external irradiation from patients recently treated with 131 I. Tissue attenuation and iodine biokinetics were considered in the patient in a larger comprehensive effort to improve external dose rate estimates. The external dose rate estimates are based on Monte Carlo simulations using the Phantom with Movable Arms and Legs (PIMAL), previously developed by Oak Ridge National Laboratory and the United States Nuclear Regulatory Commission. PIMAL was employed to model the relative positions of the 131 I patient and members of the public in three exposure scenarios: (1) traveling on a bus in a total of six seated or standing permutations, (2) two nursing home cases where a caregiver is seated at 30 cm from the patient’s bedside and a nursing home resident seated 250 cm away from the patient in an adjacent bed, and (3) two hotel cases where the patient and a guest are in adjacent rooms with beds on opposite sides of the common wall, with the patient and guest both in bed and either seated back-to-back or lying head to head. The biokinetic model predictions of the retention and distribution of 131 I in the patient assumed a single voiding of urinary bladder contents that occurred during the trip at 2, 4, or 8 h after 131 I administration for the public transportation cases, continuous first-order voiding for the nursing home cases, and regular periodic voiding at 4, 8, or 12 h after administration for the hotel room cases. Organ specific activities of 131 I

  12. Analysis of the mortality among Cogema workers monitored for external radiation exposure

    International Nuclear Information System (INIS)

    Metz-Flamant, C.; Hitz, M.; Samson, E.; Rogel, A.; Telle-Lamberton, M.; Tirmarche, M.; Caer, S.; Quesne, B.

    2006-01-01

    The present study follows 9287 Cogema workers exposed to low level of ionizing radiation from the beginning of employment to the end of 1994. This paper presents analyses of the mortality of Cogema workers monitored for external radiation exposure and the relation between their mortality and their cumulative external radiation dose. Workers were followed up for an average of 13 years. The percentage of subjects lost to follow up was less than 1%. during the follow-up period, 441 deaths occurred. The mean cumulative dose among the whole cohort was 19.4 mSv. As expected, the mortality of the cohort was lower than that of the French national population. The healthy worker effect is often observed in other nuclear workers studies. Part of the healthy worker effect is explained by a proportion of unemployed persons in general population, with a higher mortality rate. All causes S.M.R. increased with calendar period and duration of employment. this increase was not significant for all cancers S.M.R. by duration of employment. This could illustrate the decrease of the initial selection at employment with time. A significant increase in risk was observed for all cancers excluding leukemia mortality with increase of radiation dose in the 15-country study. Significant excess of leukemia by cumulative radiation exposure was observed in the 3-country study and was borderline significant in the 15-country study and in the UK National register for radiation workers study. A positive trend, not statistically significant, by level of external doses was observed in our study for all cancers and leukemia excluding chronic lymphatic leukemia mortality, but the analyses lack of statistical power. A significant trend was observed only for non-Hodgkin lymphoma death, but considering the large number of statistic tests computed, this result must be carefully interpreted. A borderline significant trend was observed for lung cancer death, a significant increase risk of lung cancer death

  13. Evaluation of an external exposure of a worker during manipulation with waste packages stored in Bohunice radioactive waste treatment centre

    International Nuclear Information System (INIS)

    Slimak, A.; Hrncir, T.; Necas, V.

    2012-01-01

    The paper briefly describes current state of radioactive waste management as well as radioactive waste treatment and conditioning technologies used in Bohunice Radioactive Waste Treatment Centre. Radioactive Waste management includes pretreatment, treatment, conditioning, storage, transport and disposal of radioactive waste. Presented paper deals with the evaluation of an external exposure of a worker during manipulation with fibre-reinforced concrete container stored under shelter object. The external exposure of a worker was evaluated using VISIPLAN 3D ALARA code. (Authors)

  14. Structural Continuum Modeling of Space Shuttle External Tank Foam Insulation

    Science.gov (United States)

    Steeve, Brian; Ayala, Sam; Purlee, T. Eric; Shaw, Phillip

    2006-01-01

    This document is a viewgraph presentation reporting on work in modeling the foam insulation of the Space Shuttle External Tank. An analytical understanding of foam mechanics is required to design against structural failure. The Space Shuttle External Tank is covered primarily with closed cell foam to: Prevent ice, Protect structure from ascent aerodynamic and engine plume heating, and Delay break-up during re-entry. It is important that the foam does not shed unacceptable debris during ascent environment. Therefore a modeling of the foam insulation was undertaken.

  15. Exposure to Family Violence and Internalizing and Externalizing Problems Among Spanish Adolescents.

    Science.gov (United States)

    Izaguirre, Ainhoa; Calvete, Esther

    2018-04-01

    Exposure to intimate partner violence (IPV) and child maltreatment may have devastating consequences on children's development. The aim of this research was to examine the predictive associations between exposure to violence at home (witnessing violence against the mother and/or direct victimization by the parents) and adolescent internalizing and externalizing problems. A total of 613 Spanish adolescents (13-18 years) took part in this study. Results indicate that psychological victimization by the parents predicted an increase in anxious/depressive symptoms, aggressive and rule-breaking behavior, and substance abuse at Time 2. In addition, rule-breaking behavior predicted an increase in adolescents' substance abuse at Time 2. Concerning gender, psychological victimization predicted an increase in anxiety/depression, aggressive behavior, rule-breaking behavior, and substance abuse in boys; whereas in girls, psychological victimization only predicted an increase in anxiety/depression.

  16. Prediction models for successful external cephalic version: a systematic review.

    Science.gov (United States)

    Velzel, Joost; de Hundt, Marcella; Mulder, Frederique M; Molkenboer, Jan F M; Van der Post, Joris A M; Mol, Ben W; Kok, Marjolein

    2015-12-01

    To provide an overview of existing prediction models for successful ECV, and to assess their quality, development and performance. We searched MEDLINE, EMBASE and the Cochrane Library to identify all articles reporting on prediction models for successful ECV published from inception to January 2015. We extracted information on study design, sample size, model-building strategies and validation. We evaluated the phases of model development and summarized their performance in terms of discrimination, calibration and clinical usefulness. We collected different predictor variables together with their defined significance, in order to identify important predictor variables for successful ECV. We identified eight articles reporting on seven prediction models. All models were subjected to internal validation. Only one model was also validated in an external cohort. Two prediction models had a low overall risk of bias, of which only one showed promising predictive performance at internal validation. This model also completed the phase of external validation. For none of the models their impact on clinical practice was evaluated. The most important predictor variables for successful ECV described in the selected articles were parity, placental location, breech engagement and the fetal head being palpable. One model was assessed using discrimination and calibration using internal (AUC 0.71) and external validation (AUC 0.64), while two other models were assessed with discrimination and calibration, respectively. We found one prediction model for breech presentation that was validated in an external cohort and had acceptable predictive performance. This model should be used to council women considering ECV. Copyright © 2015. Published by Elsevier Ireland Ltd.

  17. External radiation exposure and radiotoxicity considerations in plutonium/uranium mixed-oxide fuel fabrication

    International Nuclear Information System (INIS)

    Williams, R.A.; Crosby, E.H.

    1974-01-01

    Nuclear-reactor-produced plutonium emits significant electromagnetic and neutron radiations. In addition, because of its high specific alpha activity and its tendency to deposit in the lung and the soft tissues of the bone, plutonium presents a significant radiotoxicity hazard. Shielding, containment, and dosimetry techniques practiced at the Nuclear Materials and Equipment Corporation (NUMEC) have resulted in exemplary annual safety report statistics relevant to non-remote-handling plutonium operations. Whereas a few employees exceeded the NUMEC external exposure action level, no employee exceeded the Regulatory maximum permissible external exposure. In addition, a few employees were observed to have a lung burden in excess of the minimum sensitivity of an in vivo counting system, and one employee was observed by in vivo counting to have a lung burden in excess of the maximum permissible for a brief period. No employee was observed to have a body burden as indicated by a positive quarterly urinalysis result. Further, there were no serious incidents at the facility requiring immediate Regulatory notification, and there were no moderate incidents at the facility requiring 24-h Regulatory notification. However, there were a few reportable incidents at the facility requiring 30-day Regulatory notification, and there were a few minor incidents at the facility requiring the preparation of a NUMEC Incident Report. Details of this safety record are presented along with the health physics techniques that have contributed to the results

  18. Individual monitoring of external exposure in terms of personal dose equivalent, Hp(d)

    International Nuclear Information System (INIS)

    Fantuzzi, E.

    2001-01-01

    The institute for Radiation Protection of ENEA - Bologna has organised a one day-workshop on the subject: Individual monitoring of external exposure in terms of personal dose equivalent, H p (d). The aim of the workshop was the discussion of the new implications and modifications to be expected in the routine individual monitoring of external radiation, due to the issue of the Decree 241/00 (G.U. 31/8/2000) in charge since 01/01/2001. The decree set up in Italian law the standards contained in the European Directive EURATOM 96/29-Basic Standards for the Protection of Health of Workers and the General Public against Dangers arising from Ionizing Radiation. Among others, the definition of the operational quantities for external radiation for personal and environmental monitoring, H p (d) e H * (d) respectively as defined by ICRU (International Commission for Radiation Units and Measurements), requires to update the methods of measurements and calibration of the personal dosemeters and environmental monitors. This report collects the papers presented at the workshop dealing with the Personal Dose Equivalent, H p (d), the conversion coefficients, H p (d)/K a e H p (d)/ , obtained through Monte Carlo calculations published by ICRU and ICRP (International Commission for Radiation Protection), the new calibration procedures and the practical implication in the routine of individual monitoring in terms of H p (d). Eventually, in the last chapter, the answers to Frequently Asked Questions (FAQ) are briefly reported [it

  19. Changes of medullary hemopoiesis produced by chronic exposure to tritium oxide and external γ-radiation

    International Nuclear Information System (INIS)

    Murzina, L.D.; Muksinova, K.N.

    1982-01-01

    A comparative study of a chronic effect of tritium oxide ( 3 HOH) and external γ-radiation by 137 Cs on medullary hemopoiesis was conducted in experiments on Wistar rats. 3 HOH was administered for 3mos., 37x10 4 Bk per lg per of body mass daily (the absorbed dose 10.8 Gy), external irradiation was given in correlated values of dose rates and integral doses. Bone marrow depopulation was 1.9 times as deeper in rats exposed to 3 HOH as compared to that in irradiated rats. This difference is caused by early and stable inhibition of erythropoiesis with the administration of the radionuclide. The integral index showing the injuring effect of tritium on erythropoiesis was 4 times as high as compared to that of external γ-irradiation by 137 Cs. The time course of value of the proliferative pool of bone marrow granulocytes with the exposure to 2 types of radiation was monotypic. Differences in maturing and functioning granulocytic pools were marked in early time of the experiment

  20. Correlation effects in the Ising model in an external field

    International Nuclear Information System (INIS)

    Borges, H.E.; Silva, P.R.

    1983-01-01

    The thermodynamic properties of the spin-1/2 Ising Model in an external field are evaluated through the use of the exponential differential operator method and Callen's exact relations. The correlations effects are treated in a phenomenological approach and the results are compared with other treatments. (Author) [pt

  1. The calculation of dose from external photon exposures using reference human phantoms and Monte Carlo methods. Pt. 7. Organ doses due to parallel and environmental exposure geometries

    Energy Technology Data Exchange (ETDEWEB)

    Zankl, M. [GSF - Forschungszentrum fuer Umwelt und Gesundheit Neuherberg GmbH, Oberschleissheim (Germany). Inst. fuer Strahlenschutz; Drexler, G. [GSF - Forschungszentrum fuer Umwelt und Gesundheit Neuherberg GmbH, Oberschleissheim (Germany). Inst. fuer Strahlenschutz; Petoussi-Henss, N. [GSF - Forschungszentrum fuer Umwelt und Gesundheit Neuherberg GmbH, Oberschleissheim (Germany). Inst. fuer Strahlenschutz; Saito, K. [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan)

    1997-03-01

    This report presents a tabulation of organ and tissue equivalent dose as well as effective dose conversion coefficients, normalised to air kerma free in air, for occupational exposures and environmental exposures of the public to external photon radiation. For occupational exposures, whole-body irradiation with idealised geometries, i.e. broad parallel beams and fully isotropic radiation incidence, is considered. The directions of incidence for the parallel beams are anterior-posterior, posterior-anterior, left lateral, right lateral and a full 360 rotation around the body`s longitudinal axis. The influence of beam divergence on the body doses is also considered as well as the dependence of effective dose on the angle of radiation incidence. Regarding exposure of the public to environmental sources, three source geometries are considered: exposure from a radioactive cloud, from ground contamination and from the natural radionuclides distributed homogeneously in the ground. The precise angular and energy distributions of the gamma rays incident on the human body were taken into account. The organ dose conversion coefficients given in this catalogue were calculated using a Monte Carlo code simulating the photon transport in mathematical models of an adult male and an adult female, respectively. Conversion coefficients are given for the equivalent dose of 23 organs and tissues as well as for effective dose and the equivalent dose of the so-called `remainder`. The organ equivalent dose conversion coefficients are given separately for the adult male and female models and - as arithmetic mean of the conversion coefficients of both - for an average adult. Fitted data of the coefficients are presented in tables; the primary raw data as resulting from the Monte Carlo calculation are shown in figures together with the fitted data. (orig.)

  2. The calculation of dose from external photon exposures using reference human phantoms and Monte Carlo methods. Pt. 7. Organ doses due to parallel and environmental exposure geometries

    International Nuclear Information System (INIS)

    Zankl, M.

    1997-03-01

    This report presents a tabulation of organ and tissue equivalent dose as well as effective dose conversion coefficients, normalised to air kerma free in air, for occupational exposures and environmental exposures of the public to external photon radiation. For occupational exposures, whole-body irradiation with idealised geometries, i.e. broad parallel beams and fully isotropic radiation incidence, is considered. The directions of incidence for the parallel beams are anterior-posterior, posterior-anterior, left lateral, right lateral and a full 360 rotation around the body's longitudinal axis. The influence of beam divergence on the body doses is also considered as well as the dependence of effective dose on the angle of radiation incidence. Regarding exposure of the public to environmental sources, three source geometries are considered: exposure from a radioactive cloud, from ground contamination and from the natural radionuclides distributed homogeneously in the ground. The precise angular and energy distributions of the gamma rays incident on the human body were taken into account. The organ dose conversion coefficients given in this catalogue were calculated using a Monte Carlo code simulating the photon transport in mathematical models of an adult male and an adult female, respectively. Conversion coefficients are given for the equivalent dose of 23 organs and tissues as well as for effective dose and the equivalent dose of the so-called 'remainder'. The organ equivalent dose conversion coefficients are given separately for the adult male and female models and - as arithmetic mean of the conversion coefficients of both - for an average adult. Fitted data of the coefficients are presented in tables; the primary raw data as resulting from the Monte Carlo calculation are shown in figures together with the fitted data. (orig.)

  3. Study on the measurements and evaluation of environmental external exposure after a nuclear accident

    International Nuclear Information System (INIS)

    Sakamoto, R.; Saito, K.; Tsutsumi, M.

    2001-01-01

    Several important issues which affect external exposure in contaminated Chernobyl areas have been investigated using field measurements and computational simulations since 1992. The objectives of the study were: 1) the development of a mobile survey method to collect radiation data over the contaminated wide areas in a shot time; 2) the verification of a method to infer external dose to the population; 3) the provision of basic data used for evaluation of external dose due to gamma ray using a Monte Carlo simulation method. To develop a method to rapidly measure radiation over wide areas and map the extend of fallout, a mobile survey system was constructed and tested; the conversion factors to convert the measured data to required quantities were examined; and finally a detailed contamination map was created. The field surveys were implemented by using a land rover and a helicopter. To infer external dose to inhabitants, radiation measurements were carried out in the living environments using accurate dose meters in addition to individual dose measurements using glass dosimeters. Individual doses were inferred from occupancy factors and dose rate data measured with portable dose rate meters in and around houses. The evaluated doses were compared to directly measured individual doses with glass dosimeters in the seven settlements. A good agreement was observed with an error margin of approximate 20%. Basic data used for the evaluation of environmental gamma-ray dose rate were calculated using a Monte Carlo method. The following two kinds of data have been provided from the calculation: a) conversion factors from the nuclide concentration in the ground to the air kerma rate at 1 m height; and b) shielding factors of a typical Chernobyl house for gamma radiation. (M. Suetake)

  4. Evaluation of external exposures of the population of Ozyorsk, Russia, with luminescence measurements of bricks.

    Science.gov (United States)

    Woda, Clemens; Jacob, P; Ulanovsky, A; Fiedler, I; Mokrov, Y; Rovny, S

    2009-11-01

    Recently discovered historical documents indicate that large releases of noble gases (mainly (41)Ar and radioactive isotopes of Kr and Xe) from the Mayak Production Association (MPA) over the period from 1948 to 1956 may have caused considerable external exposures of both, inhabitants of Ozyorsk and former inhabitants of villages at the upper Techa River. To quantify this exposure, seven brick samples from three buildings in Ozyorsk, located 8-10 km north-northwest from the radioactive gas release points, were taken. The absorbed dose in brick was measured in a depth interval of 3-13 mm below the exposed surface of the bricks by means of the thermoluminescence (TL) and the optically stimulated luminescence (OSL) method. Generally, luminescence properties using TL were more favorable for precise dose determination than using OSL, but within their uncertainties the results from both methods agree well with each other. The absorbed dose due to natural radiation was assessed and subtracted under the assumption of the bricks to be completely dry. The weighted average of the anthropogenic dose for all samples measured by TL and OSL is 10 +/- 9 and 1 +/- 9 mGy, respectively. An upper limit for a possible anthropogenic dose in brick that would not be detected due to the measurement uncertainties is estimated at 24 mGy. This corresponds to an effective dose of about 21 mSv. A similar range of values is obtained in recently published dispersion calculations that were based on reconstructed MPA releases. It is concluded that the release of radioactive noble gases from the radiochemical and reactor plants at Mayak PA did not lead to a significant external exposure of the population of Ozyorsk. In addition, the study demonstrates the detection limit for anthropogenic doses in ca. 60-year-old bricks to be about 24 mGy, if luminescence methods are used.

  5. Evaluation of Cost and Effectiveness of Decontamination Scenarios on External Radiation Exposure in Fukushima

    Energy Technology Data Exchange (ETDEWEB)

    Yasutaka, T.; Naito, W. [National Institute of Advanced Industrial Science and Technology (Japan)

    2014-07-01

    Despite the enormous cost associated with radiation decontamination, almost no quantitative assessment has been performed on the relationship between the potential reduction in long-term radiation exposure and the costs of the various decontamination strategies considered for the decontamination areas in Fukushima. In order to establish effective and pragmatic decontamination strategies for use in the radiation contaminated areas in Fukushima, a holistic approach for assessing decontamination strategies, their costs, and long-term external radiation doses is needed. The objective of the present study is to evaluate the cost and effectiveness of decontamination scenarios in the decontamination areas in Fukushima in regard to external radiation exposure. The choice of decontamination strategies in the decontamination areas should be based on a comprehensive analysis of multiple attributes such as radiological, economic, and socio-psychological attributes. The cost and effectiveness of the different decontamination strategies is not sole determinant of the decontamination strategies of the special decontamination area but is one of the most important attributes when making the policy decision. In the current study, we focus on radiological and economic attributes in determining decontamination strategies. A geographical information system (GIS) was used to relate the predicted external dose in the affected areas to the number of potential inhabitants and the land use in the areas. A comprehensive review of the costs of various decontamination methods was conducted as part of the analysis. The results indicate that aerial decontamination in the special decontamination areas in Fukushima would be effective for reducing the air dose rate to the target level in a short period of time in some but not all of the areas. In a standard scenario, the analysis of cost suggests that decontamination costs of decontamination in Fukushima was estimated to be up to approximately 5

  6. Externalities in a life cycle model with endogenous survival☆

    Science.gov (United States)

    Kuhn, Michael; Wrzaczek, Stefan; Prskawetz, Alexia; Feichtinger, Gustav

    2011-01-01

    We study socially vs individually optimal life cycle allocations of consumption and health, when individual health care curbs own mortality but also has a spillover effect on other persons’ survival. Such spillovers arise, for instance, when health care activity at aggregate level triggers improvements in treatment through learning-by-doing (positive externality) or a deterioration in the quality of care through congestion (negative externality). We combine an age-structured optimal control model at population level with a conventional life cycle model to derive the social and private value of life. We then examine how individual incentives deviate from social incentives and how they can be aligned by way of a transfer scheme. The age-patterns of socially and individually optimal health expenditures and the transfer rate are derived. Numerical analysis illustrates the working of our model. PMID:28298810

  7. Health Externalities and Heat savings in Energy System Modelling

    DEFF Research Database (Denmark)

    Zvingilaite, Erika

    Energy consumption and production can cause air pollution with global impact, such as CO2, and local/regional air pollutants, such as SO2, NOx and PM2.5, as a result of fuel combustion. Use of fossil fuels leads to global CO2 emissions and causes global warming effects, regardless place or height......-related external costs can be internalised, for instance, in energy system modelling. External costs of global warming and human health damage can be of comparable magnitude.However, in contrast to global CO2 impacts, air pollution damage to human health depends on a number of factors, related to location...... and included in an energy system optimisation model. The performed analysis of the Danish heat and power sector concludes that accounting for spatial variation of health damage costs in heat and power system optimisation model has an effect on the optimal technology mix and distribution of energy plants among...

  8. The dynamic model of choosing an external funding instrument

    Directory of Open Access Journals (Sweden)

    Irena HONKOVA

    2015-06-01

    Full Text Available Making a decision about using a specific funding source is one of the most important tasks of financial management. The utilization of external sources features numerous advantages yet staying aware of diverse funding options is not easy for financial managers. Today it is crucial to quickly identify an optimum possibility and to make sure that all relevant criteria have been considered and no variant has been omitted. Over the long term it is also necessary to consider the category of time as changes made today do not affect only the current variables but they also have a significant impact on the future. This article aims to identify the most suitable model of choosing external funding sources that would describe the dynamics involved. The first part of the paper considers the theoretical background of external funding instrument and of decision criteria. The making of financial decisions is a process consisted of weighing the most suitable variants, selecting the best variant, and controlling the implementation of accepted proposals. The second part analyses results of the research - decisive weights of the criteria. Then it is created the model of the principal criteria Weighted Average Cost of Capital (Dynamic model WACC. Finally it is created the Dynamic Model of Choosing an External Funding Instrument. The created decision-making model facilitates the modeling of changes in time because it is crucial to know what future consequences lies in decisions made the contemporary turbulent world. Each variant features possible negative and positive changes of varying extent. The possibility to simulate these changes can illustrate an optimal variant to a decision-maker.

  9. A theoretical study for the real-time assessment of external gamma exposure using equivalent-volume numerical integration

    International Nuclear Information System (INIS)

    Han, Moon Hee

    1995-02-01

    An approximate method for estimating gamma external dose due to an arbitrary distribution of radioactive material has been developed. For the assessment of external gamma dose, the space over which radioactive material is distributed has been assumed to be composed of hexagonal cells. The evaluation of three-dimensional integration over the space is an extremely time-consuming task. Hence, a different approach has been used for the study, i.e., a equivalent-volume spherical approach in which a regular hexahedron is modeled as a equivalent-volume sphere to simplify the integration. For the justification of the current approach, two case studies have been performed: a comparison with a point source approximation and a comparison of external dose rate with the Monte Carlo integration. These comparisons show that the current approach gives reasonable results in a physical sense. Computing times of the developed and Monte Carlo integration method on VAX system have been compared as a function of the number of hexagonal cells. This comparison shows that CPU times for both methods are comparable in the region of small number of cells, but in the region of large number, Monte Carlo integration needs much more computing times. The proposed method is shown to have an accuracy equivalent to Monte Carlo method with an advantage of much shorter calculation time. Then, the method developed here evaluates early off-site consequences of a nuclear accident. An accident consequence assessment model has been integrated using Gaussian puff model which is used to obtain the distribution of radioactive material in the air and on the ground. For this work, the real meteorological data measured at Kori site for 10 years (1976 - 1985) have been statistically analyzed for obtaining site-specific conditions. The short-term external gamma exposures have been assessed for several site-specific meteorological conditions. The results show that the extent and the pattern of short-term external

  10. Evaluation of the external exposure to Rn-222 progeny in air

    International Nuclear Information System (INIS)

    Ali, E.M.; Taha, T.M.; Gomaa, M.A.; El-Hussein, A.M.; Ahmed, A.A.

    2003-01-01

    The aim of this paper is to evaluate the Rn-222 progeny annual effective dose, skin dose and effective doses to different organs such as Gonad, Lung, Red Marrow, Bone surface, Thyroid, and the Remainder. Dose Coefficients of external exposure to Rn-222 in air was used in mSv s/Bqm -3 to calculate the organ doses. The study was monitored for two places, Nuclear Research Center and Al-Minia University. We have confirmed that the inhalation modes, sleep, sitting, light and heavy exercise influence the activity inhalation rate Bq/hr. It varies from 0.3 to 39.6 Bq/hr., the organ doses of Pb-214 is higher than Bi-214/Po-214 and Po-218 respectively in the case of the organ dose relative to environmental media

  11. Calculation of age-dependent effective doses for external exposure using the MCNP code

    International Nuclear Information System (INIS)

    Hung, Tran Van

    2013-01-01

    Age-dependent effective dose for external exposure to photons uniformly distributed in air were calculated. Firstly, organ doses were calculated with a series of age-specific MIRD-5 type phantoms using the Monte Carlo code MCNP. The calculations were performed for mono-energetic photon sources with source energies from 10 keV to 5 MeV and for phantoms of newborn, 1, 5, 10, and 15 years-old and adult. Then, the effective doses to the different age-phantoms from the mono-energetic photon sources were estimated based on the obtained organ doses. From the calculated results, it is shown that the effective doses depend on the body size; the effective doses in younger phantoms are higher than those in the older phantoms, especially below 100 keV. (orig.)

  12. Calculation of age-dependent effective doses for external exposure using the MCNP code

    Energy Technology Data Exchange (ETDEWEB)

    Hung, Tran Van [Research and Development Center for Radiation Technology, ThuDuc, HoChiMinh City (VT)

    2013-07-15

    Age-dependent effective dose for external exposure to photons uniformly distributed in air were calculated. Firstly, organ doses were calculated with a series of age-specific MIRD-5 type phantoms using the Monte Carlo code MCNP. The calculations were performed for mono-energetic photon sources with source energies from 10 keV to 5 MeV and for phantoms of newborn, 1, 5, 10, and 15 years-old and adult. Then, the effective doses to the different age-phantoms from the mono-energetic photon sources were estimated based on the obtained organ doses. From the calculated results, it is shown that the effective doses depend on the body size; the effective doses in younger phantoms are higher than those in the older phantoms, especially below 100 keV. (orig.)

  13. Assessing Discriminative Performance at External Validation of Clinical Prediction Models.

    Directory of Open Access Journals (Sweden)

    Daan Nieboer

    Full Text Available External validation studies are essential to study the generalizability of prediction models. Recently a permutation test, focusing on discrimination as quantified by the c-statistic, was proposed to judge whether a prediction model is transportable to a new setting. We aimed to evaluate this test and compare it to previously proposed procedures to judge any changes in c-statistic from development to external validation setting.We compared the use of the permutation test to the use of benchmark values of the c-statistic following from a previously proposed framework to judge transportability of a prediction model. In a simulation study we developed a prediction model with logistic regression on a development set and validated them in the validation set. We concentrated on two scenarios: 1 the case-mix was more heterogeneous and predictor effects were weaker in the validation set compared to the development set, and 2 the case-mix was less heterogeneous in the validation set and predictor effects were identical in the validation and development set. Furthermore we illustrated the methods in a case study using 15 datasets of patients suffering from traumatic brain injury.The permutation test indicated that the validation and development set were homogenous in scenario 1 (in almost all simulated samples and heterogeneous in scenario 2 (in 17%-39% of simulated samples. Previously proposed benchmark values of the c-statistic and the standard deviation of the linear predictors correctly pointed at the more heterogeneous case-mix in scenario 1 and the less heterogeneous case-mix in scenario 2.The recently proposed permutation test may provide misleading results when externally validating prediction models in the presence of case-mix differences between the development and validation population. To correctly interpret the c-statistic found at external validation it is crucial to disentangle case-mix differences from incorrect regression coefficients.

  14. Evaluation of external exposure during building and operation of concrete bridges constructions that reuse the conditionally released steels - 59120

    International Nuclear Information System (INIS)

    Panik, Michal; Necas, Vladimir

    2012-01-01

    This paper presents ongoing results of the project presented at ICEM'10 [1] related to the topics of reusing the conditionally released materials from decommissioning. The subject of the reuse of conditionally released materials in this case is modeling of bridge constructions which reuse the conditionally released steel in the form of reinforcement bars for the concrete bridges. A general approach for the project was presented at ICEM'10. The activities of the project continue in evaluating the individual effective doses from the external exposure based on reused conditionally released steels separately for public and for professionals (the internal exposure will be evaluated in next stages of the project). Evaluated scenarios are related to critical groups of professionals constructing the bridges (worker's scenarios). The computer code VISIPLAN 3D ALARA 4.0 planning tool was used for the calculation of the individual effective dose for professionals. Various limits of the annual individual effective dose are used for the evaluation of calculation results. The aim of the ongoing modeling is to develop a set of data of maximal radioactivity concentration for individual radionuclides in the conditionally released steel used in the bridges model constructions in order not to exceed the limits for the individual effective dose. (authors)

  15. Natural radioactivity and external gamma radiation exposure at the coastal Red Sea in Egypt

    International Nuclear Information System (INIS)

    Harb, S.

    2008-01-01

    Radionuclides which present in different beach sands are sources of external exposure that contribute to the total radiation exposure of human. In this work, superficial samples of beach sand were collected from the Red Sea coastline (Ras Gharib, Hurghada, Safaga, Qusier and Marsa Alam areas) and at 20 km on Qena-Safaga road. The distribution of natural radionuclides in sand beach samples was studied by gamma spectrometry. The activity concentrations of primordial and artificial radionuclides in samples that are collected from the coastal environment of the Red Sea were 19.2 ± 3 Bq kg -1 for 210 Pb, 21.1 ± 1 Bq kg -1 for 226 Ra, 22.7 ± 2 Bq kg -1 for 238 U, 1.0 ± 0.1 Bq kg -1 for 235 U, 11.6 ± 1 Bq kg -1 for 228 Ra, 13.0 ± 1 Bq kg -1 for 228 Th, 12.4 ± 1 Bq kg -1 for 232 Th, 930 ± 32 Bq kg -1 for 40 K and 1.2 ± 0.3 Bq kg -1 for 137 Cs. The mean external gamma-dose rate was 62.5 ± 3.2 nSv h -1 , 54.4 ± 2.8 nGy h -1 Ra equivalent activity (Ra eq ) was 107 ± 5.8 Bq kg -1 , 0.86 ± 0.04 Bq kg -1 for representative level index (Iγ) and effective dose rate was 0.067 ± 0.003 mSv y -1 in beach sand red sea, in air due to naturally occurring radionuclides. (authors)

  16. Effects of soil water content on the external exposure of fauna to radioactive isotopes.

    Science.gov (United States)

    Beaugelin-Seiller, K

    2016-01-01

    Within a recent model intercomparison about radiological risk assessment for contaminated wetlands, the influence of soil saturation conditions on external dose rates was evidenced. This issue joined concerns of assessors regarding the choice of the soil moisture value to input in radiological assessment tools such as the ERICA Tool. Does it really influence the assessment results and how? This question was investigated under IAEA's Modelling and Data for Radiological Impacts Assessments (MODARIA) programme via 42 scenarios for which the soil water content varied from 0 (dry soil) to 100% (saturated soil), in combination with other parameters that may influence the values of the external dose conversion coefficients (DCCs) calculated for terrestrial organisms exposed in soil. A set of α, β, and γ emitters was selected in order to cover the range of possible emission energies. The values of their external DCCs varied generally within a factor 1 to 1.5 with the soil water content, excepted for β emitters that appeared more sensitive (DCCs within a factor of about 3). This may be of importance for some specific cases or for upper tiers of radiological assessments, when refinement is required. But for the general purpose of screening assessment of radiological impact on fauna and flora, current approaches regarding the soil water content are relevant. Copyright © 2015 Elsevier Ltd. All rights reserved.

  17. Theoretical vs. measured risk estimates for the external exposure to ionizing radiation pathway - a case study of a major industrial site

    International Nuclear Information System (INIS)

    Dundon, S.T.

    1996-01-01

    Two methods of estimating the risk to industrial receptors to ionizing radiation are presented here. The first method relies on the use of the U.S. Environmental Protection Agency (EPA) external exposure slope factor combined with default exposure parameters for industrial land uses. The second method employs measured exposure rate date and site-specific exposure durations combined with the BEIR V radiological risk coefficient to estimate occupational risk. The uncertainties in each method are described qualitatively. Site-specific information was available for the exposure duration and the exposure frequency as well as historic dosimetry information. Risk estimates were also generated for the current regulatory cleanup level (removal risks included) and for a no action scenario. The study showed that uncertainties for risks calculated using measured exposure rates and site-specific exposure parameters were much lower and defendable than using EPA slope factors combined with default exposure parameters. The findings call into question the use of a uniform cleanup standard for depleted uranium that does not account for site-specific land uses and relies on theoretical models rather than measured exposure rate information

  18. The long or short of it: Determinants of foreign currency exposure in external balance sheets

    OpenAIRE

    LANE, PHILIP RICHARD

    2009-01-01

    Recently, there have been numerous advances in modelling optimal international portfolio allocations in macroeconomic models. A major focus of this literature has been on the role of currency movements in determining portfolio returns that may hedge various macroeconomic shocks. However, there is little empirical evidence on the foreign currency exposures that are embedded in international balance sheets. Using a new database, we provide stylized facts concerning the cross-country and time-se...

  19. The Long or Short of it: Determinants of Foreign Currency Exposure in External Balance Sheets

    OpenAIRE

    Lane, Philip R.; Shambaugh, Jay C

    2008-01-01

    Recently, there have been numerous advances in modelling optimal international portfolio allocations in macroeconomic models. A major focus of this literature has been on the role of currency movements in determining portfolio returns that may hedge various macroeconomic shocks. However, there is little empirical evidence on the foreign currency exposures that are embedded in international balance sheets. Using a new database, we provide stylized facts concerning the cross-country and time-se...

  20. Mercury risk assessment combining internal and external exposure methods for a population living near a municipal solid waste incinerator.

    Science.gov (United States)

    Deng, Chunyan; Xie, Han; Ye, Xuejie; Zhang, Haoran; Liu, Maodian; Tong, Yindong; Ou, Langbo; Yuan, Wen; Zhang, Wei; Wang, Xuejun

    2016-12-01

    Risk assessments for human health have been conducted for municipal solid waste incinerators (MSWIs) in many western countries, whereas only a few risk assessments have been performed for MSWIs in developing countries such as China where the use of waste incineration is increasing rapidly. To assess the mercury exposure risks of a population living near the largest MSWI in South China, we combined internal exposure and external exposure assessment with an individual-specific questionnaire. The mercury concentrations in air, soil, and locally collected food around the MSWI were assessed. The total mercury (T-Hg) and methylmercury (MeHg) of 447 blood samples from a control group, residential exposure group, and MSWI workers were measured. The internal and external exposures of the subject population were analyzed. Significant difference in MeHg concentrations was observed between the control group and the exposed group, between the control group and the MSWI workers, and between the exposed group and the MSWI workers (median levels: 0.70 μg/L, 0.81 μg/L, and 1.02 μg/L for the control group, exposed group, and MSWI workers, respectively). The MeHg/T-Hg ratio was 0.51 ± 0.19, 0.59 ± 0.17 and 0.58 ± 0.25, respectively. Multiple linear regression analysis indicated that MeHg concentrations were positively correlated with the gaseous mercury in the air. Combining internal and external exposure assessment showed that the direct contribution of MSWI emissions was minor compared with the dietary contribution. The external and internal exposures were well matched with each other. This study also suggested that an integrated method combining internal and external exposure assessment with an individual-specific questionnaire is feasible to assess the risks for a population living near a MSWI. Copyright © 2016 Elsevier Ltd. All rights reserved.

  1. Determinants of dermal exposure relevant for exposure modelling in regulatory risk assessment.

    Science.gov (United States)

    Marquart, J; Brouwer, D H; Gijsbers, J H J; Links, I H M; Warren, N; van Hemmen, J J

    2003-11-01

    Risk assessment of chemicals requires assessment of the exposure levels of workers. In the absence of adequate specific measured data, models are often used to estimate exposure levels. For dermal exposure only a few models exist, which are not validated externally. In the scope of a large European research programme, an analysis of potential dermal exposure determinants was made based on the available studies and models and on the expert judgement of the authors of this publication. Only a few potential determinants appear to have been studied in depth. Several studies have included clusters of determinants into vaguely defined parameters, such as 'task' or 'cleaning and maintenance of clothing'. Other studies include several highly correlated parameters, such as 'amount of product handled', 'duration of task' and 'area treated', and separation of these parameters to study their individual influence is not possible. However, based on the available information, a number of determinants could clearly be defined as proven or highly plausible determinants of dermal exposure in one or more exposure situation. This information was combined with expert judgement on the scientific plausibility of the influence of parameters that have not been extensively studied and on the possibilities to gather relevant information during a risk assessment process. The result of this effort is a list of determinants relevant for dermal exposure models in the scope of regulatory risk assessment. The determinants have been divided into the major categories 'substance and product characteristics', 'task done by the worker', 'process technique and equipment', 'exposure control measures', 'worker characteristics and habits' and 'area and situation'. To account for the complex nature of the dermal exposure processes, a further subdivision was made into the three major processes 'direct contact', 'surface contact' and 'deposition'.

  2. Harmonisation (legal, dosimetric, quality aspects) of individual monitoring, and integration of monitoring for external and internal exposures (EURADOS working group)

    International Nuclear Information System (INIS)

    Lopez, M.A.; Currivan, L.; Falk, R.; Olko, P.; Wernli, C.; Castellani, C.M.; Dijk, J.W.E. van

    2003-01-01

    The EURADOS Working Group II on 'Harmonisation of individual monitoring' consists of experts from almost all EU Member States and Newly Associated States (NAS), involved in tasks related to the assessment of doses for internal and external radiation. The final objective is to achieve harmonisation in individual monitoring for occupational exposures. Sub-group 2 activities are focused on investigating how the results from personal dosemeters for external radiation and workplace monitoring and from monitoring for internal exposure can be combined into a complete and consistent system of individual monitoring. Three questionnaires were prepared, covering Individual monitoring of external radiation (Questionnaire 1), 'Internal exposure' (Questionnaire 2) and 'Natural sources of radiation at workplace' (Questionnaire 3). With the agreement of a 'contact-person' selected in each country, the distribution of the three EURADOS 2002 questionnaires was carried out by e-mail among the dosimetry facilities of 28 European countries. The preliminary results of these actions are presented here. (author)

  3. Reconstructing exposures from biomarkers using exposure-pharmacokinetic modeling--A case study with carbaryl.

    Science.gov (United States)

    Brown, Kathleen; Phillips, Martin; Grulke, Christopher; Yoon, Miyoung; Young, Bruce; McDougall, Robin; Leonard, Jeremy; Lu, Jingtao; Lefew, William; Tan, Yu-Mei

    2015-12-01

    Sources of uncertainty involved in exposure reconstruction for short half-life chemicals were characterized using computational models that link external exposures to biomarkers. Using carbaryl as an example, an exposure model, the Cumulative and Aggregate Risk Evaluation System (CARES), was used to generate time-concentration profiles for 500 virtual individuals exposed to carbaryl. These exposure profiles were used as inputs into a physiologically based pharmacokinetic (PBPK) model to predict urinary biomarker concentrations. These matching dietary intake levels and biomarker concentrations were used to (1) compare three reverse dosimetry approaches based on their ability to predict the central tendency of the intake dose distribution; and (2) identify parameters necessary for a more accurate exposure reconstruction. This study illustrates the trade-offs between using non-iterative reverse dosimetry methods that are fast, less precise and iterative methods that are slow, more precise. This study also intimates the necessity of including urine flow rate and elapsed time between last dose and urine sampling as part of the biomarker sampling collection for better interpretation of urinary biomarker data of short biological half-life chemicals. Resolution of these critical data gaps can allow exposure reconstruction methods to better predict population-level intake doses from large biomonitoring studies. Published by Elsevier Inc.

  4. External exposure assessment in dwelling built with phosphogypsum; Avaliacao da exposicao externa em residencia construida com fosfogesso

    Energy Technology Data Exchange (ETDEWEB)

    Villaverde, Freddy Lazo

    2008-07-01

    In this study it was evaluated the viability of the use of phosphogypsum plates as a building material in the dwelling construction. Thus, the effective dose due to external gamma exposure was assessed through the {sup 226}Ra, {sup 232}Th, {sup 210}Pb e {sup 40}K activity concentration in phosphogypsum plates. Samples of this material were analyzed by high resolution gamma spectrometry for their natural radionuclide activity concentration. The radium equivalent activity and extern ai and inter nai hazard indices were also calculated. The plates were made with phosphogypsum from fertilizer industries located in Cajati, Cubatao and Uberaba. The samples were identified according to phosphogypsum origin, Cajati (CA), Cubatao (CT) and Uberaba (UB). The activity concentrations results varied from 15.9 to 392 Bq kg{sup -1} for {sup 226}Ra, 26.1 to 253 Bq kg{sup -1} for {sup 232}Th, and 27.4 to 852 Bq kg{sup -1} for {sup 210}Pb. The results of {sup 40}K were lower than 81 Bq kg{sup -1}. The annual effective dose was obtained through the dosimetric model with reference standard room concept, the results were 0.02 mSv y{sup -1} for a house built with phosphogypsum from origin CA, 0.2 mSvy{sup -1} for CT phosphogypsum and 0.14 mSvy{sup -1} for UB phosphogypsum, everything the effective doses were below 1 mSvy{sup -1}, an annual effective dose limit for public exposure by International Commission on Radiological Protection. (author)

  5. External radiation dose and cancer mortality among French nuclear workers. Considering potential confounding by internal radiation exposure

    Energy Technology Data Exchange (ETDEWEB)

    Fournier, L.; Laurent, O.; Samson, E.; Caer-Lorho, S.; Laurier, D.; Leuraud, K. [Institute for Radiological Protection and Nuclear Safety, Fontenay aux Roses (France). Ionizing Radiation Epidemiology Lab.; Laroche, P. [AREVA, Paris (France); Le Guen, B. [EDF, Saint Denis (France)

    2016-11-15

    French nuclear workers have detailed records of their occupational exposure to external radiation that have been used to examine associations with subsequent cancer mortality. However, some workers were also exposed to internal contamination by radionuclides. This study aims to assess the potential for bias due to confounding by internal contamination of estimates of associations between external radiation exposure and cancer mortality. A cohort of 59,004 workers employed for at least 1 year between 1950 and 1994 by CEA (Commissariat a l'Energie Atomique), AREVA NC, or EDF (Electricite de France) and badge-monitored for external radiation exposure were followed through 2004 to assess vital status and cause of death. A flag based on a workstation-exposure matrix defined four levels of potential for internal contamination. Standardized mortality ratios were assessed for each level of the internal contamination indicator. Poisson regression was used to quantify associations between external radiation exposure and cancer mortality, adjusting for potential internal contamination. For solid cancer, the mortality deficit tended to decrease as the levels of potential for internal contamination increased. For solid cancer and leukemia excluding chronic lymphocytic leukemia, adjusting the dose-response analysis on the internal contamination indicator did not markedly change the excess relative risk per Sievert of external radiation dose. This study suggests that in this cohort, neglecting information on internal dosimetry while studying the association between external dose and cancer mortality does not generate a substantial bias. To investigate more specifically the health effects of internal contamination, an effort is underway to estimate organ doses due to internal contamination.

  6. External radiation dose and cancer mortality among French nuclear workers: considering potential confounding by internal radiation exposure.

    Science.gov (United States)

    Fournier, L; Laurent, O; Samson, E; Caër-Lorho, S; Laroche, P; Le Guen, B; Laurier, D; Leuraud, K

    2016-11-01

    French nuclear workers have detailed records of their occupational exposure to external radiation that have been used to examine associations with subsequent cancer mortality. However, some workers were also exposed to internal contamination by radionuclides. This study aims to assess the potential for bias due to confounding by internal contamination of estimates of associations between external radiation exposure and cancer mortality. A cohort of 59,004 workers employed for at least 1 year between 1950 and 1994 by CEA (Commissariat à l'Energie Atomique), AREVA NC, or EDF (Electricité de France) and badge-monitored for external radiation exposure were followed through 2004 to assess vital status and cause of death. A flag based on a workstation-exposure matrix defined four levels of potential for internal contamination. Standardized mortality ratios were assessed for each level of the internal contamination indicator. Poisson regression was used to quantify associations between external radiation exposure and cancer mortality, adjusting for potential internal contamination. For solid cancer, the mortality deficit tended to decrease as the levels of potential for internal contamination increased. For solid cancer and leukemia excluding chronic lymphocytic leukemia, adjusting the dose-response analysis on the internal contamination indicator did not markedly change the excess relative risk per Sievert of external radiation dose. This study suggests that in this cohort, neglecting information on internal dosimetry while studying the association between external dose and cancer mortality does not generate a substantial bias. To investigate more specifically the health effects of internal contamination, an effort is underway to estimate organ doses due to internal contamination.

  7. AirPEx. Air Pollution Exposure Model

    Energy Technology Data Exchange (ETDEWEB)

    Freijer, J.I.; Bloemen, H.J.Th.; De Loos, S.; Marra, M.; Rombout, P.J.A.; Steentjes, G.M.; Van Veen, M.P.

    1997-12-01

    Analysis of inhalatory exposure to air pollution is an important area of investigation when assessing the risks of air pollution for human health. Inhalatory exposure research focuses on the exposure of humans to air pollutants and the entry of these pollutants into the human respiratory tract. The principal grounds for studying the inhalatory exposure of humans to air pollutants are formed by the need for realistic exposure/dose estimates to evaluate the health effects of these pollutants. The AirPEx (Air Pollution Exposure) model, developed to assess the time- and space-dependence of inhalatory exposure of humans to air pollution, has been implemented for use as a Windows 3.1 computer program. The program is suited to estimating various exposure and dose quantities for individuals, as well as for populations and subpopulations. This report describes the fundamentals of the AirPEx model and provides a user manual for the computer program. Several examples included in the report illustrate the possibilities of the AirPEx model in exposure assessment. The model will be used at the National Institute of Public Health and the Environment as a tool in analysing the current exposure of the Dutch population to air pollutants. 57 refs.

  8. 76 FR 365 - Exposure Modeling Public Meeting

    Science.gov (United States)

    2011-01-04

    ... classification for ecological risk assessments using aerial photography and GIS data. Dermal contact, movement... ENVIRONMENTAL PROTECTION AGENCY [EPA-HQ-OPP-2009-0879; FRL-8860-5] Exposure Modeling Public Meeting AGENCY: Environmental Protection Agency (EPA). ACTION: Notice. SUMMARY: An Exposure Modeling...

  9. Evaluation of external radiation exposure of personnel involved in veterinary nuclear medicine

    International Nuclear Information System (INIS)

    Komatsubara, N.; Ito, N.; Natsuhori, M.; Sano, T.; Ishikawa, T.; Hatakeyama, S.; Futatsugawa, S.; Terasaki, K.; Hirayama, H.

    2005-01-01

    Veterinary nuclear medicine has been widely applied in the US and Europe, especially for dogs, cats, and horses. The needs of the nuclear medicine in veterinary practice are also growing in Japan. This study was performed in order to make a safety guideline for veterinary nuclear medicine in Japan. Two sorts of well often medically used radionuclide, 18 F and 99m Tc were chosen for evaluating the exposed doses of the veterinarian, the animal owner, and the general public. Air absorption doses around a physical phantom containing radioactive materials ( 18 F or 99m Tc) were measured by glass dosimeters. (Asahi Techno Glass Ltd.) It was verified that the measurement values were corresponding to the calculation values using EGS4. Then, canine pectoral and abdominal mathematical phantom was designed, external radiation exposure of the veterinarian, the animal owner and the public from the phantom containing radioactive materials were calculated by using EGS4. Calculated exposure doses were compared with the dose limit or the dose constraint. (20mSv/yr for the veterinarian: ICRP, 5mSv/yr for the animal owner: IAEA, and 1mSv/yr for the general public: ICRP 2 ). The future integration exposed doses of the animal owner and the public didn't exceed the dose constraint or the dose limit at the release after 24 hours of the radiopharmaceutical administering. In this study, all the calculation conditions were set up on the safety side. Therefore, it is thought that actual exposed doses lower considerably. The safety guideline for the veterinary nuclear medicine in Japan will be established by further application of this type of research. (author)

  10. Modeling external constraints: Applying expert systems to nuclear plants

    International Nuclear Information System (INIS)

    Beck, C.E.; Behera, A.K.

    1993-01-01

    Artificial Intelligence (AI) applications in nuclear plants have received much attention over the past decade. Specific applications that have been addressed include development of models and knowledge-bases, plant maintenance, operations, procedural guidance, risk assessment, and design tools. This paper examines the issue of external constraints, with a focus on the use of Al and expert systems as design tools. It also provides several suggested methods for addressing these constraints within the Al framework. These methods include a State Matrix scheme, a layered structure for the knowledge base, and application of the dynamic parameter concept

  11. Disorders of oxidation homeostasis in the blood and organs of rats under the influence of external x-ray exposure

    International Nuclear Information System (INIS)

    Uzlenkova, N.Je.

    2009-01-01

    The study was performed in the blood and organs (lungs and skin) of male rats weighing 160-180 g. Single external x-ray exposure to minimal and medial lethal doses causes stable disorders in oxidation homeostasis resulting in peroxidation state and development of chronic oxidative stress in the organism of the exposed rats.

  12. External Sector Rebalancing and Endogenous Trade Imbalance Models

    Directory of Open Access Journals (Sweden)

    John Whalley

    2012-12-01

    Full Text Available I discuss the need for trade models to incorporate endogenous trade imbalances both to more adequately capture the reality of a global economy with large imbalances and pressures from the financial crisis for countries to reduce imbalances. Conventional general equilibrium trade models implicitly incorporate monetary neutrality and either have zero trade balance as a property of equilibrium, or have a fixed and exogenous trade imbalance. Models which are discussed here have a variety of forms. In one, central banks fix exchange rates and operate a non accommodative monetary policy and accumulate reserves. Changes in both trade and monetary policies change reserve accumulative and with the external sector imbalances. This is a reflection of China’s current policy regime. In another intertemporal preferences allow for simultaneous inter commodity and intertemporal trade across countries, and with changed intertemporal trade changed external sector imbalances within the period. These formulations are each applied to potential tax initiatives to aid in rebalancing.

  13. Internal exposure from building materials exhaling (222)Rn and (220)Rn as compared to external exposure due to their natural radioactivity content.

    Science.gov (United States)

    Ujić, Predrag; Celiković, Igor; Kandić, Aleksandar; Vukanac, Ivana; Durasević, Mirjana; Dragosavac, Dusan; Zunić, Zora S

    2010-01-01

    The main scope of this paper is to point out the importance of introducing radon and thoron exhalation measurements from building materials in the regulating frame. Currently (2009), such a regulation of this kind of exposure is not explicitly included in the Serbian regulating network. To this end, this work reports concentration measurements of (226)Ra, (232)Th and (40)K and radon and thoron exhalation rates from building materials used in Serbia. Following detailed analysis, it was noticed that both internal exposures to radon and/or thoron exhaling from building materials may exceed external exposures to their precursors contained therein.

  14. Occupational exposure from external radiation used in medical practices in Pakistan by film badge dosimetry

    International Nuclear Information System (INIS)

    Jabeen, A.; Munir, M.; Khalil, A.; Masood, M.; Akhter, P.

    2010-01-01

    Occupational exposure data of workers due to external sources of radiation in various medical practices such as nuclear medicine (NM), radiotherapy and diagnostic radiology (DR) in Pakistan were collected and analysed. Whole-body doses of workers were measured by film badge dosimetry technique during 2003-2007. Annual average effective dose in NM, radio-therapy and DR varied in the range of 1.39-1.80, 1.05-1.45 and 1.22-1.71 mSv, respectively, during 2003-2007. These values are quite low and well below the annual limit of 20 mSv averaged over a period of 5 consecutive years. Nobody received the radiation dose >50 mSv in any single year over a period of 5 consecutive years; therefore, no overexposure case has been detected. Decreasing trend of annual average dose values in aforementioned categories of work during 2003-2007 indicates the improvement of radiation protection status in medical field in Pakistan. (authors)

  15. Dose conversion coefficients calculated using a series of adult Japanese voxel phantoms against external photon exposure

    International Nuclear Information System (INIS)

    Sato, Kaoru; Endo, Akira; Saito, Kimiaki

    2008-10-01

    This report presents a complete set of conversion coefficients of organ doses and effective doses calculated for external photon exposure using five Japanese adult voxel phantoms developed at the Japan Atomic Energy Agency (JAEA). At the JAEA, high-resolution Japanese voxel phantoms have been developed to clarify the variation of organ doses due to the anatomical characteristics of Japanese, and three male phantoms (JM, JM2 and Otoko) and two female phantoms (JF and Onago) have been constructed up to now. The conversion coefficients of organ doses and effective doses for the five voxel phantoms have been calculated for six kinds of idealized irradiation geometries from monoenergetic photons ranging from 0.01 to 10 MeV using EGS4, a Monte Carlo code for the simulation of coupled electron-photon transport. The dose conversion coefficients are given as absorbed dose and effective dose per unit air-kerma free-in-air, and are presented in tables and figures. The calculated dose conversion coefficients are compared with those of voxel phantoms based on the Caucasian and the recommended values in ICRP74 in order to discuss (1) variation of organ dose due to the body size and individual anatomy, such as position and shape of organs, and (2) effect of posture on organ doses. The present report provides valuable data to study the influence of the body characteristics of Japanese upon the organ doses and to discuss developing reference Japanese and Asian phantoms. (author)

  16. A geostatistical investigation of the spatial variation of external gamma exposure in urban area of Pocos de Caldas Plateau

    International Nuclear Information System (INIS)

    Silva, Nivaldo C.; Macacini, Jose F.; Taddei, Maria H.T.; Montano, Marcelo; Fontes, Aurelio T.

    2008-01-01

    Full text: The Pocos de Caldas Plateau has been recognized as High Level of Natural Radiation Area for a long time. It consists in an alkaline intrusion with some uranium and thorium anomalies, where the first Brazilian uranium mining and milling facilities is located. Due to these facts, the population of Pocos de Caldas city shows a great deal of concern about radiation health effects. This perception of the risks of radiation exposure leads to much confusion among the population that attributes an imaginary excess (without an scientific support) of cancer cases and deformities in newborns in the city to radiation. In order to obtain information for help radiation risks management by government and to explore the spatial variation external gamma exposure a survey in the urban area of Pocos de Caldas city was done. The measurements were performed using a Mobile Radioactivity Measurement System - Mobisys (ESM Eberline model FHT 1376). The system consists of a high-sensitivity 5-liter scintillation detector, an electronic for measurement system that is able to on-line separate natural and artificial gamma radiation (Natural Background Rejection Detector NBR), one compact Global Positioning System GPS and a computer (notebook). Data was collected at approximately 50,000 points spread over all streets of city. The obtained results ranged from 40 nSv.h -1 to 420 nSv.h -1 where the mean value was 112 nSv.h -1 . The spatial distribution of gamma exposure over the city is quite homogeneous with lowest and highest values in western and southern area, respectively. (author)

  17. Models for pulmonary lethality and morbidity after irradiation from internal and external sources

    International Nuclear Information System (INIS)

    Scott, B.R.; Filipy, R.E.; Hahn, E.F.

    1989-05-01

    This report provides a hazard-function model for estimating the risk of death from radiation pneumonitis and/or pulmonary fibrosis following a light-water nuclear power accident. A similar model is also provided for estimating the prevalence of respiratory functional morbidity among those that survive death from acute effects. Hazard-function models for lethality and for morbidity were constructed using the cumulative hazard estimator H, which is related to the risk estimator R through the equation R = 1-exp(-H). The estimator H can be calculated using information provided in the report. The method of calculation depends on the exposure scenario. In general, the total normalized dose X for lethality or for morbidity is calculated. For lethality, X = 1 corresponds to a median lethal dose (LD 50 ); for morbidity, X = 1 corresponds to a median effective dose (ED 50 ). H is related to X by the equation H = 1n(2)X/sup V/, where V depends on the type of radiation (or radiations) involved. Contributions to X can arise from each of two main modes of exposure: (1) brief exposure of the lung, at a relatively high dose rate, to mainly external gammas, followed by (2) chronic internal alpha, and/or beta, and/or gamma irradiation of the lung. Equations are provided for calculating the contributions to X from both modes of exposure. 73 refs., 16 figs., 2 tabs

  18. Modeling dynamic behavior of superconducting maglev systems under external disturbances

    Science.gov (United States)

    Huang, Chen-Guang; Xue, Cun; Yong, Hua-Dong; Zhou, You-He

    2017-08-01

    For a maglev system, vertical and lateral displacements of the levitation body may simultaneously occur under external disturbances, which often results in changes in the levitation and guidance forces and even causes some serious malfunctions. To fully understand the effect of external disturbances on the levitation performance, in this work, we build a two-dimensional numerical model on the basis of Newton's second law of motion and a mathematical formulation derived from magnetoquasistatic Maxwell's equations together with a nonlinear constitutive relation between the electric field and the current density. By using this model, we present an analysis of dynamic behavior for two typical maglev systems consisting of an infinitely long superconductor and a guideway of different arrangements of infinitely long parallel permanent magnets. The results show that during the vertical movement, the levitation force is closely associated with the flux motion and the moving velocity of the superconductor. After being disturbed at the working position, the superconductor has a disturbance-induced initial velocity and then starts to periodically vibrate in both lateral and vertical directions. Meanwhile, the lateral and vertical vibration centers gradually drift along their vibration directions. The larger the initial velocity, the faster their vibration centers drift. However, the vertical drift of the vertical vibration center seems to be independent of the direction of the initial velocity. In addition, due to the lateral and vertical drifts, the equilibrium position of the superconductor in the maglev systems is not a space point but a continuous range.

  19. Developmental Timing and Continuity of Exposure to Interparental Violence and Externalizing Behavior as Prospective Predictors of Dating Violence

    Science.gov (United States)

    Narayan, Angela J.; Englund, Michelle M.; Egeland, Byron

    2014-01-01

    This study investigated the prospective pathways of children's exposure to interparental violence (EIPV) in early and middle childhood and externalizing behavior in middle childhood and adolescence as developmental predictors of dating violence perpetration and victimization at ages 23 and 26 years. Participants (N = 168) were drawn from a longitudinal study of low-income families. Path analyses examined whether timing or continuity of EIPV predicted dating violence and whether timing or continuity of externalizing behavior mediated these pathways. Results indicated that EIPV in early childhood directly predicted perpetration and victimization at age 23. There were significant indirect effects from EIPV to dating violence through externalizing behavior in adolescence and life stress at age 23. Independent of EIPV, externalizing behavior in middle childhood also predicted dating violence through externalizing behavior in adolescence and life stress at age 23, but this pathway stemmed from maltreatment. These results highlight that the timing of EIPV and both the timing and continuity of externalizing behavior are critical risks for the intergenerational transmission of dating violence. Findings support a developmental perspective that negative early experiences and children's externalizing behavior are powerful influences for dating violence in early adulthood. PMID:24229543

  20. Developmental timing and continuity of exposure to interparental violence and externalizing behavior as prospective predictors of dating violence.

    Science.gov (United States)

    Narayan, Angela J; Englund, Michelle M; Egeland, Byron

    2013-11-01

    This study investigated the prospective pathways of children's exposure to interparental violence (EIPV) in early and middle childhood and externalizing behavior in middle childhood and adolescence as developmental predictors of dating violence perpetration and victimization at ages 23 and 26 years. Participants (N = 168) were drawn from a longitudinal study of low-income families. Path analyses examined whether timing or continuity of EIPV predicted dating violence and whether timing or continuity of externalizing behavior mediated these pathways. Results indicated that EIPV in early childhood directly predicted perpetration and victimization at age 23. There were significant indirect effects from EIPV to dating violence through externalizing behavior in adolescence and life stress at age 23. Independent of EIPV, externalizing behavior in middle childhood also predicted dating violence through externalizing behavior in adolescence and life stress at age 23, but this pathway stemmed from maltreatment. These results highlight that the timing of EIPV and both the timing and the continuity of externalizing behavior are critical risks for the intergenerational transmission of dating violence. The findings support a developmental perspective that negative early experiences and children's externalizing behavior are powerful influences for dating violence in early adulthood.

  1. Calculating external doses from contaminated soil with the computer model SOILD

    International Nuclear Information System (INIS)

    Chen, Y.; LePoire, D.; Yu, C.

    1991-01-01

    The SOILD computer model was developed for calculating the effective dose equivalent from external exposure to distributed gamma sources in soil. It is designed to assess external doses under various exposure scenarios that may be encountered in environmental restoration programs. The model's four major functional features address (a) dose versus source depth in soil, (b) shielding of clean cover soil, (c) area of contamination, and (d) nonuniform distribution of sources. The model can also adjust doses when there are variations in soil densities for both source and cover soils. It is supported by a data base of ∼500 radionuclides. A sample calculation was performed by SOILD to determine the effective dose equivalent for a uniform source distribution in soil. The soil density was assumed to be 1.6 g/cm 3 , and the source strength was assumed to be 1 pCi/cm 3 . The following radionuclides were studied: 60 C, 131 I, 137+D Cs, 238+D U, and 226+D Ra ('+D' denotes the parent nuclide and daughters)

  2. Critical evaluation of the external occupational exposure in nuclear medicine services in Brazil

    International Nuclear Information System (INIS)

    Kubo, Ana Luiza Silva Lima

    2016-01-01

    Currently in Brazil (2016), there are 421 Nuclear Medicine Services (NMS). In nuclear medicine, the possibility of occupational internal contamination and external exposure is unavoidable. The chest individual monitoring, to estimate the effective dose, is mandatory, but the extremity monitoring is not always made. The aim of this study was to conduct a survey of data for external exposure of NMS professionals in Brazil from 1987 to 2010, analysing them in terms of trends and comparing them with measurements carried out in this work and in other countries. Although most of the NMS is still located in large urban centres (54% in the Southeast region), there is no state without any NMS. The increasing number of NMS has generated the need for more professionals. In the year 1987, they were 755 workers and, in 2010, 4134, with the following distribution of specialties: 29% of Nuclear Medicine Technicians (NMT), 23% of Nursing professionals, 29% of Physicians and 3% of Physicists. The average annual effective dose reached more than 3.0 mSv in some regions of the country, from 1987 to 2010, but tends to 1.0 mSv in 2010. The highest doses, as expected, are received by NMT and Nursing. The professionals who handle radiopharmaceuticals have their hands much more exposed than the chest. During 2010, only 31% of NMT and 16% of Nursing used extremity dosimeters as compared to chest dosimeters. The data from the measurements indicate that not all individual dosimeters are used properly. Generally, both in the measurements as in national registries, the hand doses were higher for professionals who prepared the radiopharmaceutical (NMT) than those who injected (Nursing). The value measured by chest dosimeters can be used to estimate the equivalent dose to the eye lenses, except for NMT at preparation practices at conventional NMS, where the equivalent dose of the lens is about 2 times higher than the dose at the chest. The most exposed areas of the hands are the tips of the index

  3. External exposure rates from terrestrial radiation at Guarapari and Meaipe in Brazil

    International Nuclear Information System (INIS)

    Fujinami, N.; Koga, T.; Morishima, H.

    2000-01-01

    Recently epidemiological and cytogenetic studies on inhabitants living in high background radiation areas have been carried out in order to examine health effects of exposure to low dose radiation. Guarapari and Meaipe are towns built on the monazite sand region along the Atlantic coast in Brazil, which is one of the widely known high background radiation areas in the world. As an initial step toward studies on health effects of high background radiation on inhabitants living in Guarapari and Meaipe, we surveyed absorbed dose rates in air in these towns with a portable NaI(Tl) scintillation detector in September 1998. Sand and soil were also sampled there so as to determine the concentrations of Th-232 and Ra-226 in them. In Guarapari and Meaipe, dose rates in the streets ranged from 0.1 to 0.4 μ Gy/h except for a few places such as near the Areia Preta beach and Meaipe beach. Dose rates inside houses were lower than 0.2 μ Gy/h except that two houses attained a dose rate of 0.4 μ Gy/h. Our effective dose rate from external terrestrial irradiation (outdoors and indoors) was 0.17 μ Sv/h on the average, during the period of our three day stay in Guarapari and Meaipe. From comparison of our present values with those observed in the 1960s, which were cited in UNSCEAR reports, it is indicated that dose rate levels have decreased clearly in downtown, while the levels have scarcely changed in beaches and unpaved beach streets which have not been developed yet. This fact suggests that the natural radiation environment of Guarapari and Meaipe has varied with urbanization which brought paved streets, and changes in the structure and building materials of houses. A detailed survey is necessary in order to evaluate present absorbed dose rates in air in this area. (author)

  4. Chapter three: methodology of exposure modeling

    CSIR Research Space (South Africa)

    Moschandreas, DJ

    2002-12-01

    Full Text Available methodologies and models are reviewed. Three exposure/measurement methodologies are assessed. Estimation methods focus on source evaluation and attribution, sources include those outdoors and indoors as well as in occupational and in-transit environments. Fate...

  5. Lower Bounds in the Asymmetric External Memory Model

    DEFF Research Database (Denmark)

    Jacob, Riko; Sitchinava, Nodari

    2017-01-01

    Motivated by the asymmetric read and write costs of emerging non-volatile memory technologies, we study lower bounds for the problems of sorting, permuting and multiplying a sparse matrix by a dense vector in the asymmetric external memory model (AEM). Given an AEM with internal (symmetric) memory...... of size M, transfers between symmetric and asymmetric memory in blocks of size B and the ratio ω between write and read costs, we show Ω(min (N, ωN/B logω M/B N/B) lower bound for the cost of permuting N input elements. This lower bound also applies to the problem of sorting N elements. This proves...

  6. Modeling Noise Sources and Propagation in External Gear Pumps

    Directory of Open Access Journals (Sweden)

    Sangbeom Woo

    2017-07-01

    Full Text Available As a key component in power transfer, positive displacement machines often represent the major source of noise in hydraulic systems. Thus, investigation into the sources of noise and discovering strategies to reduce noise is a key part of improving the performance of current hydraulic systems, as well as applying fluid power systems to a wider range of applications. The present work aims at developing modeling techniques on the topic of noise generation caused by external gear pumps for high pressure applications, which can be useful and effective in investigating the interaction between noise sources and radiated noise and establishing the design guide for a quiet pump. In particular, this study classifies the internal noise sources into four types of effective load functions and, in the proposed model, these load functions are applied to the corresponding areas of the pump case in a realistic way. Vibration and sound radiation can then be predicted using a combined finite element and boundary element vibro-acoustic model. The radiated sound power and sound pressure for the different operating conditions are presented as the main outcomes of the acoustic model. The noise prediction was validated through comparison with the experimentally measured sound power levels.

  7. Modeling of external radiation from the transport of radionuclides across a canyon

    International Nuclear Information System (INIS)

    Bowen, B.M.; Olsen, W.A.; Van Etten, D.; Chen, I-li.

    1986-01-01

    The Los Alamos Meson Physics Facility (LAMPF) is an 800-million electron volt, l mA intensity linear proton accelerator used for studying subatomic particles at relativistic velocities. Routine operation of the accelerator results in the formation of short-lived air activation products, primarily in the beam stop section of LAMPF. This study presents the results of monitoring and modeling external radiation levels from LAMPF emissions at three locations during 1984. Measured radiation exposures are presented for all three locations during a 49-day period. Hourly radiation levels are calculated for all sites and compared with the prevalent wind patterns during the study period. Predicted daily levels are compared with measured values at all of the sites. Accuracy of the model is compared for day and night conditions. Annual model predictions are also compared with TLD measurements

  8. Overview of the ICRP/ICRU adult reference computational phantoms and dose conversion coefficients for external idealised exposures

    CERN Document Server

    Endo, A; Zankl, M; Bolch, W E; Eckerman, K F; Hertel, N E; Hunt, J G; Pelliccioni, M; Schlattl, H; Menzel, H-G

    2014-01-01

    This paper reviews the ICRP Publications 110 and 116 describing the reference computational phantoms and dose conversion coefficients for external exposures. The International Commission on Radiological Protection (ICRP) in its 2007 Recommendations made several revisions to the methods of calculation of the protection quantities. In order to implement these recommendations, the DOCAL task group of the ICRP developed computational phantoms representing the reference adult male and female and then calculated a set of dose conversion coefficients for various types of idealised external exposures. This paper focuses on the dose conversion coefficients for neutrons and investigates their relationship with the conversion coefficients of the protection and operational quantities of ICRP Publication 74. Contributing factors to the differences between these sets of conversion coefficients are discussed in terms of the changes in phantoms employed and the radiation and tissue weighting factors.

  9. External exposure dose of car mechanics during the maintenance of the cars from the risk cautionary area

    International Nuclear Information System (INIS)

    Kawakami, Hiroto; Yamada, Norikazu; Sasaki, Satoru; Kawasaki, Satoru

    2011-12-01

    At the request of the Local Nuclear Emergency Response Headquarters, JNES has estimated the effective external exposure dose of car mechanics during the maintenance of the cars from the risk cautionary area. JNES investigated the contamination of the cars from the risk cautionary area and of the average cars at Fukushima city cooperated by the Japan Automobile Dealers Association. Data of screed cars by the Local Nuclear Emergency Response Headquarters is also considered in. Effective external exposure dose of car mechanics treating the cars screened with the emergency situation screening level is estimated to be less than 1 mSv/y under the conservative conditions. This result shows that particular health concern isn't necessary for them. (author)

  10. Evaluation of external exposure in a radioactive waste deposit; Avaliacao da exposicao externa em um deposito de rejeitos radioativos

    Energy Technology Data Exchange (ETDEWEB)

    Oliveira, Sergio Quinet de; Pereira, Wagner de Souza; Py Junior, Delcy de Azevedo; Dores, Luis Augusto de Carvalho Bresser; Dantas, Marcelino Vicente de Almeida; Silva, Ana Claudia Antunes; Garcia Filho, Oswaldo, E-mail: wspereira@inb.gov.b, E-mail: sergioquinet@inb.gov.b, E-mail: delcy@inb.gov.b, E-mail: luisdores@inb.gov.b, E-mail: marcelino@inb.go.b, E-mail: anasilva@inb.gov.b, E-mail: ogarcia@inb.gov.b [Industrias Nucleares do Brasil (UTM/INB), Pocos de Caldas, MG (Brazil). Unidade de Tratamento de Minerio

    2011-10-26

    The ore treatment unit (OTU) of Industrias Nucleares do Brasil (INB), located at Caldas municipality - Minas Gerais, Brazil, posses a radioactive deposit, coming mainly from the chemical processing of monazite sands for obtention of 'rare earths'. The main components of these waste are the 'torta II (thorium rich residues) and the 'mesothorium' ({sup 228}Ra rich residues) - conditioned in steel drums (200 liters), plastic pumps (100 liters) or underground silos. These loaders are deposited in waste loading warehouses existent at the OTU and periodic evaluations of the external exposure rates (mR/h) are part of the 'Programa de Monitoracao Radiologica Ocupacional' of the unit. This paper presents a brief history of origins of this waste deposit and the material found there, and also the result of a routine monitoring of the external exposure rates

  11. CONSEXPO 3.0, consumer exposure and uptake models

    NARCIS (Netherlands)

    Veen MP van; LBM

    2001-01-01

    The report provides a modelling approach to consumer exposure to chemicals, based on mathematical contact, exposure and uptake models. For each route of exposure, a number of exposure and uptake models are included. A general framework joins the exposure and uptake models selected by the user. By

  12. Correlation-based Transition Modeling for External Aerodynamic Flows

    Science.gov (United States)

    Medida, Shivaji

    Conventional turbulence models calibrated for fully turbulent boundary layers often over-predict drag and heat transfer on aerodynamic surfaces with partially laminar boundary layers. A robust correlation-based model is developed for use in Reynolds-Averaged Navier-Stokes simulations to predict laminar-to-turbulent transition onset of boundary layers on external aerodynamic surfaces. The new model is derived from an existing transition model for the two-equation k-omega Shear Stress Transport (SST) turbulence model, and is coupled with the one-equation Spalart-Allmaras (SA) turbulence model. The transition model solves two transport equations for intermittency and transition momentum thickness Reynolds number. Experimental correlations and local mean flow quantities are used in the model to account for effects of freestream turbulence level and pressure gradients on transition onset location. Transition onset is triggered by activating intermittency production using a vorticity Reynolds number criterion. In the new model, production and destruction terms of the intermittency equation are modified to improve consistency in the fully turbulent boundary layer post-transition onset, as well as ensure insensitivity to freestream eddy viscosity value specified in the SA model. In the original model, intermittency was used to control production and destruction of turbulent kinetic energy. Whereas, in the new model, only the production of eddy viscosity in SA model is controlled, and the destruction term is not altered. Unlike the original model, the new model does not use an additional correction to intermittency for separation-induced transition. Accuracy of drag predictions are improved significantly with the use of the transition model for several two-dimensional single- and multi-element airfoil cases over a wide range of Reynolds numbers. The new model is able to predict the formation of stable and long laminar separation bubbles on low-Reynolds number airfoils that

  13. Thyroid cancer in the Marshallese: relative risk of short-lived internal emitters and external radiation exposure

    International Nuclear Information System (INIS)

    Lessard, E.T.; Brill, A.B.; Adams, W.H.

    1985-01-01

    In a study of the comparative effects of internal versus external irradiation of the thyroid in young people, we determined that the dose from internal irradiation of the thyroid with short-lived internal emitters produced several times less thyroid cancer than did the same dose of radiation given externally. We determined this finding for a group of 85 Marshall Islands children, who were less than 10 years of age at the time of exposure and who were accidentially exposed to internal and external thyroid radiation at an average level of 1400 rad. The external risk coefficient ranged between 2.5 and 4.9 cancers per million person-rad-years at risk, and thus, from our computations, the internal risk coefficient for the Marshallese children was estimated to range between 1.0 and 1.4 cancers per million person-rad-years at risk. In contrast, for individual more than 10 years of age at the time of exposure, the dose from internal irradiation of the thyroid with short-lived internal emitters produced several times more thyroid cancer than did the same dose of radiation given externally. The external risk coefficients for the older age groups were reported in the literature to be in the range of 1.0 to 3.3 cancers per million person-rad-years-at risk. We computed internal risk coefficients of 3.3 to 8.1 cancers per million person-rad-years at risk for adolescent and adult groups. This higher sensitivity to cancer induction in the exposed adolescents and adults, is different from that seen in other exposed groups. 14 refs., 8 tabs

  14. Thyroid cancer in the Marshallese: relative risk of short-lived internal emitters and external radiation exposure

    International Nuclear Information System (INIS)

    Lessard, E.T.; Brill, A.B.; Adams, W.H.

    1986-01-01

    In a study of the comparative effects of internal versus external irradiation of the thyroid in young people, we determined that the dose from internal irradiation of the thyroid with short-lived internal emitters produced several times less thyroid cancer than did the same dose of radiation given externally. The authors determined this finding for a group of 85 Marshall Islands children, who were less than 10 years of age at the time of exposure and who were accidentally exposed to internal and external thyroid radiation at an average level of 1400 rad. The external risk coefficient ranged between 2.5 and 4.9 cancers per million person-rad-years at risk, and thus, from our computations, the internal risk coefficient for the Marshallese children was estimated to range between 1.0 and 1.4 cancers per million person-rad-years at risk. In contrast, for individuals more than 10 years of age at the time of exposure, the dose from internal irradiation of the thyroid with short-lived internal emitters produced several times more thyroid cancer than did the same dose of radiation given externally. The external risk coefficients for the older age groups were reported in the above literature to be in the range of 1.0 to 3.3 cancers per million person-rad-years-at risk. The authors computed internal risk coefficients of 3.3 to 8.1 cancers per million person-rad-years at risk for adolescent and adult groups. This higher sensitivity to cancer induction in the exposed adolescents and adults, is different from that seen in other exposed groups. The small number of cancers in the exposed population and the influence of increased levels of TSH, nonuniform irradiation of the thyroid, and thyroid cell killing at high dose make it difficult to draw firm conclusions from these studies. 14 references, 8 tables

  15. Estimators for longitudinal latent exposure models: examining measurement model assumptions.

    Science.gov (United States)

    Sánchez, Brisa N; Kim, Sehee; Sammel, Mary D

    2017-06-15

    Latent variable (LV) models are increasingly being used in environmental epidemiology as a way to summarize multiple environmental exposures and thus minimize statistical concerns that arise in multiple regression. LV models may be especially useful when multivariate exposures are collected repeatedly over time. LV models can accommodate a variety of assumptions but, at the same time, present the user with many choices for model specification particularly in the case of exposure data collected repeatedly over time. For instance, the user could assume conditional independence of observed exposure biomarkers given the latent exposure and, in the case of longitudinal latent exposure variables, time invariance of the measurement model. Choosing which assumptions to relax is not always straightforward. We were motivated by a study of prenatal lead exposure and mental development, where assumptions of the measurement model for the time-changing longitudinal exposure have appreciable impact on (maximum-likelihood) inferences about the health effects of lead exposure. Although we were not particularly interested in characterizing the change of the LV itself, imposing a longitudinal LV structure on the repeated multivariate exposure measures could result in high efficiency gains for the exposure-disease association. We examine the biases of maximum likelihood estimators when assumptions about the measurement model for the longitudinal latent exposure variable are violated. We adapt existing instrumental variable estimators to the case of longitudinal exposures and propose them as an alternative to estimate the health effects of a time-changing latent predictor. We show that instrumental variable estimators remain unbiased for a wide range of data generating models and have advantages in terms of mean squared error. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

  16. Radionuclide mobility in soils and its effect on the external radiation exposure

    International Nuclear Information System (INIS)

    Bunzl, K.; Hillmann, U.; Jacob, P.; Kretner, R.; Schimmack, W.; Tikhomirov, F.; Scheglov, A.; Arkhipov, N.P.; Arkhipov, A.N.; Alexakhin, R.M.; Kruglov, S.V.; Loschilov, N.; Ivanov, Y.; Levchuk, S.; Kashparov, V.; Oreshich, L.

    1996-01-01

    In order to predict the gamma-dose rate of 137 Cs for a period of about 100 years after the Chernobyl accident, the present vertical distribution of radiocesium in several meadow soils in the Chernobyl area and in Germany was determined and the corresponding residence half-times of this radionuclide in the various soil layers were evaluated with a compartment model. The resulting residence half-times were subsequently used to calculate the vertical distribution of 137 Cs in the soil as a function of time and finally to predict the external gamma-dose rates in air for these sites at various times. The results show that the time dependence of the relative gamma-dose rate in air D/D t=0 at both sites can be described by a two-term exponential equation. At a given time, the relative gamma-dose rate at the Chernobyl sites is always higher as compared to the German sites. This difference is the result of the slower vertical migration of 137 Cs at the Chernobyl sites

  17. Reasons between effective doses for tomographic and mathematical models due to external exposition by photons

    International Nuclear Information System (INIS)

    Kramer, R.; Khoury, H.J.; Yoriyaz, H.; Lima, F.R.A.; Loureiro, E.C.M.

    2005-01-01

    The development of Monte Carlo codes and new and sophisticated tomographic human models, or based on voxel, motivated the ICRP to propose a revision of the traditional exposition models, which have been used to calculate doses on organs and tissues using mathematical phantoms MIRD-type 5. This article presents calculations made with tomographic phantoms MAX (Male Adult voXel) and FAX (Female Adult voXel), recently developed and also, for comparison, with ADAM and Eve mathematician phantoms. All models were coupled to the EGS4 and MCNP4 codes for full body external irradiation by photons. It were simulated expositions AP, PA and rotational for energies varying between 10 keV and 10 MeV. The effective calculated doses were compared separately to evaluate: the replacement of the Monte Carlo code; the composition of the tissues and the replacement of tomographic phantoms by mathematical ones. Effective doses calculated results indicate that for external exposures by photons to introduce models based on voxels can cause a reduction of about 10% to the energies considered in this study

  18. Media Exposure: How Models Simplify Sampling

    DEFF Research Database (Denmark)

    Mortensen, Peter Stendahl

    1998-01-01

    In media planning, the distribution of exposures to more ad spots in more media (print, TV, radio) is crucial to the evaluation of the campaign. If such information should be sampled, it would only be possible in expensive panel-studies (eg TV-meter panels). Alternatively, the distribution...... of exposures may be modelled statistically, using the Beta distribution combined with the Binomial Distribution. Examples are given....

  19. EO Model for Tacit Knowledge Externalization in Socio-Technical Enterprises

    Directory of Open Access Journals (Sweden)

    Shreyas Suresh Rao

    2017-03-01

    Full Text Available Aim/Purpose: A vital business activity within socio-technical enterprises is tacit knowledge externalization, which elicits and explicates tacit knowledge of enterprise employees as external knowledge. The aim of this paper is to integrate diverse aspects of externalization through the Enterprise Ontology model. Background: Across two decades, researchers have explored various aspects of tacit knowledge externalization. However, from the existing works, it is revealed that there is no uniform representation of the externalization process, which has resulted in divergent and contradictory interpretations across the literature. Methodology\t: The Enterprise Ontology model is constructed step-wise through the conceptual and measurement views. While the conceptual view encompasses three patterns that model the externalization process, the measurement view employs certainty-factor model to empirically measure the outcome of the externalization process. Contribution: The paper contributes towards knowledge management literature in two ways. The first contribution is the Enterprise Ontology model that integrates diverse aspects of externalization. The second contribution is a Web application that validates the model through a case study in banking. Findings: The findings show that the Enterprise Ontology model and the patterns are pragmatic in externalizing the tacit knowledge of experts in a problem-solving scenario within a banking enterprise. Recommendations for Practitioners\t: Consider the diverse aspects (what, where, when, why, and how during the tacit knowledge externalization process. Future Research:\tTo extend the Enterprise Ontology model to include externalization from partially automated enterprise systems.

  20. Overview of the ICRP/ICRU adult reference computational phantoms and dose conversion coefficients for external idealised exposures

    International Nuclear Information System (INIS)

    Endo, Akira; Petoussi-Henss, Nina; Zankl, Maria; Schlattl, Helmut; Bolch, Wesley E.; Eckerman, Keith F.; Hertel, Nolan E.; Hunt, John G.; Pelliccioni, Maurizio; Menzel, Hans-Georg

    2014-01-01

    This paper reviews the ICRP Publications 110 and 116 describing the reference computational phantoms and dose conversion coefficients for external exposures. The International Commission on Radiological Protection (ICRP) in its 2007 Recommendations made several revisions to the methods of calculation of the protection quantities. In order to implement these recommendations, the DOCAL task group of the ICRP developed computational phantoms representing the reference adult male and female and then calculated a set of dose conversion coefficients for various types of idealised external exposures. This paper focuses on the dose conversion coefficients for neutrons and investigates their relationship with the conversion coefficients of the protection and operational quantities of ICRP Publication 74. Contributing factors to the differences between these sets of conversion coefficients are discussed in terms of the changes in phantoms employed and the radiation and tissue weighting factors. This paper briefly reviews the reference computational phantoms and dose conversion coefficients for external exposures that were published jointly by ICRP and ICRU. Both these publications appeared as a consequence of the ICRP 2007 Recommendations; to implement these recommendations, the ICRP has developed reference computational phantoms representing the adult male and female. These phantoms are used to calculate reference dose conversion coefficients for external and internal sources. Using the reference phantoms and methodology consistent with the 2007 Recommendations, dose conversion coefficients for both effective doses and organ-absorbed doses for various types of idealised external exposures have been calculated. These data sets supersede the existing ICRP/ICRU data sets and expand the particle types and energy ranges. For neutrons, the new effective dose conversion coefficients become smaller compared with those in ICRP74, for energies below hundreds of keV. This is mainly

  1. Federal guidelines for estimating external exposure of radiation workers in Russia

    International Nuclear Information System (INIS)

    Chizhov, K.; Kryuchkov, V.; Mark, N.K.; Szoeke, I.; Sneve, M.K.

    2017-01-01

    In this paper, an overview of Russian federal guidelines for optimizing work procedures in terms of radiation protection for planned field work is presented. The general provisions, procedures and methods for applying the principles of optimization are provided in accordance with the Radiation Safety Standards (NRB-99/2009) and Basic sanitary rules of radiation safety (OSPORB-99/2010). Jobs in environments with actual or potential radiation hazards shall be planned on the basis of the principle of optimization in order to prevent unexpected exposure of the personnel. Control and optimization of dose to workers is a continuous process, which is carried out at various stages of radiation-hazardous work under constant involvement of the personnel in the planning procedure. Implementation of the principle of optimization should include considerations for human and organizational aspects for ensuring high level safety. The planning and optimization process includes education and training of personnel, estimation of radiation doses for the upcoming work, preparations for unplanned situations, and implementation of practical safety measures within the targeted radiation-hazardous works. The optimization principle is most important in the planning phase where uncertainties in planned exposure must be considered. Variability of radiation risks related to different scenarios (choices) can be managed by modern simulation technology, and use of advanced tools (software) for simulating planned activities and conditions in digital models including the environment (premises of an industrial complex) with dynamic visualization of the radiation exposure conditions. Existing hardware and emerging information technologies allow practical application of such techniques. Application of advanced information technology can reduce uncertainties related to the radiation environment by turning invisible radiation into directly perceivable risk information. In addition, virtual reality

  2. Solid cancer mortality associated with chronic external radiation exposure at the French atomic energy commission and nuclear fuel company.

    Science.gov (United States)

    Metz-Flamant, C; Samson, E; Caër-Lorho, S; Acker, A; Laurier, D

    2011-07-01

    Studies of nuclear workers make it possible to directly quantify the risks associated with ionizing radiation exposure at low doses and low dose rates. Studies of the CEA (Commissariat à l'Energie Atomique) and AREVA Nuclear Cycle (AREVA NC) cohort, currently the most informative such group in France, describe the long-term risk to nuclear workers associated with external exposure. Our aim is to assess the risk of mortality from solid cancers among CEA and AREVA NC nuclear workers and its association with external radiation exposure. Standardized mortality ratios (SMRs) were calculated and internal Poisson regressions were conducted, controlling for the main confounding factors [sex, attained age, calendar period, company and socioeconomic status (SES)]. During the period 1968-2004, there were 2,035 solid cancers among the 36,769 CEA-AREVA NC workers. Cumulative external radiation exposure was assessed for the period 1950-2004, and the mean cumulative dose was 12.1 mSv. Mortality rates for all causes and all solid cancers were both significantly lower in this cohort than in the general population. A significant excess of deaths from pleural cancer, not associated with cumulative external dose, was observed, probably due to past asbestos exposure. We observed a significant excess of melanoma, also unassociated with dose. Although cumulative external dose was not associated with mortality from all solid cancers, the central estimated excess relative risk (ERR) per Sv of 0.46 for solid cancer mortality was higher than the 0.26 calculated for male Hiroshima and Nagasaki A-bomb survivors 50 years or older and exposed at the age of 30 years or older. The modification of our results after stratification for SES demonstrates the importance of this characteristic in occupational studies, because it makes it possible to take class-based lifestyle differences into account, at least partly. These results show the great potential of a further joint international study of

  3. Development of a new fuzzy exposure model

    International Nuclear Information System (INIS)

    Vasconcelos, Wagner Eustaquio de; Lira, Carlos Alberto Brayner de Oliveira; Texeira, Marcello Goulart

    2007-01-01

    The main topic of this study is the development of an exposure fuzzy model to evaluate the exposure of inhabitants in an area containing uranium, which present a high natural background. In this work, a fuzzy model was created, based on some of the following main factors: activity concentration of uranium, physiological factors and characteristic customs of the exposed individuals. An inference block was created to evaluate some factors of radiation exposure. For this, AHP-fuzzy technique (Analytic Hierarchic Process) was used and its application was demonstrated for a subjected population to the radiation of the natural uranium. The Mandami type fuzzy model was also created from the opinion of specialists. The Monte Carlo method was used to generate a statistics of input data and the daily average exposure served as comparison parameter between the three techniques. The output fuzzy sets were expressed in form of linguistic variables, such as high, medium and low. In the qualitative analysis, the obtained results were satisfactory when translating the opinion of the specialists. In the quantitative analysis, the obtained values are part of the same fuzzy set as the values found in literature. The global results suggest that this type of fuzzy model is highly promising for analysis of exposure to ionizing radiation. (author)

  4. Development of a new fuzzy exposure model

    Energy Technology Data Exchange (ETDEWEB)

    Vasconcelos, Wagner Eustaquio de; Lira, Carlos Alberto Brayner de Oliveira [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil). Dept. de Energia Nuclear. Grupo de Engenharia de Reatores], E-mail: wagner@ufpe.br, E-mail: cabol@ufpe.br; Texeira, Marcello Goulart [Instituto Militar de Engenharia (IME), Rio de Janeiro, RJ (Brazil). Terrestrial Modelling Group], E-mail: marcellogt@ime.eb.br

    2007-07-01

    The main topic of this study is the development of an exposure fuzzy model to evaluate the exposure of inhabitants in an area containing uranium, which present a high natural background. In this work, a fuzzy model was created, based on some of the following main factors: activity concentration of uranium, physiological factors and characteristic customs of the exposed individuals. An inference block was created to evaluate some factors of radiation exposure. For this, AHP-fuzzy technique (Analytic Hierarchic Process) was used and its application was demonstrated for a subjected population to the radiation of the natural uranium. The Mandami type fuzzy model was also created from the opinion of specialists. The Monte Carlo method was used to generate a statistics of input data and the daily average exposure served as comparison parameter between the three techniques. The output fuzzy sets were expressed in form of linguistic variables, such as high, medium and low. In the qualitative analysis, the obtained results were satisfactory when translating the opinion of the specialists. In the quantitative analysis, the obtained values are part of the same fuzzy set as the values found in literature. The global results suggest that this type of fuzzy model is highly promising for analysis of exposure to ionizing radiation. (author)

  5. Evaluating external costs of human health and environmental impacts using IAEA model SIMPACTS

    International Nuclear Information System (INIS)

    Bobric, Elena; Jelev, Adrian

    2005-01-01

    SIMPACTS (Simplified Approach for Estimating Impacts and External Costs of Electricity Generation) model developed at the International Atomic Energy Agency is a powerful and convenient tool for evaluating external costs induced by different energy sources. The model was developed for industrial countries and for developing countries as well where studies of alternatives of sustainable energy policies are conducted. The SIMPACTS allow the decision making factors involved in energy policy to have reasonable estimates of environment impacts and relating costs appealing to a rather low number of input parameters. The paper aims at analyzing by means of SIMPACTS the environmental impact produced by Cernavoda NPP operation in two cases: a) the impact of the Cernavoda NPP itself; b) the impact of an hypothetical coal based power plant of the same power level and located on the Cernavoda NPP site. The SIMPACTS modules AIRPACTS and NUCPACTS were applied to assess the impacts on human health, agricultural crops and building materials from exposure to routine atmospheric emissions and as well to quantify and value the adverse effects on human health due to routine atmospheric release of radionuclides from the NPP, via radioactive waste ground disposal or resulting from accidents in nuclear facility, respectively. The conclusion of this study based on SIMPACTS model application to assess the health effects and damage cost per year is that the Cernavoda NPP presents the lower health effects and damage cost comparing with power plants of other types

  6. Gene expression analysis in rice plants after external radiation exposure in Iitate village

    Energy Technology Data Exchange (ETDEWEB)

    Hayashi, G.; Fukumoto, M. [Institute of Development, Aging and Cancer, Tohoku University (Japan); Imanaka, T. [Research Reactor Institute, Kyoto University (Japan); Shibato, J. [Department of Anatomy I, School of Medicine, Showa University (Japan); Kubo, A. [Center for Environmental Biology and Ecosystem Studies, National Institute for Environmental Studies (Japan); Kikuchi, S. [Plant Genome Research Unit, Agrogenomics Research Center, National Institute of Agrobiological Sciences (Japan); Rakwal, R. [Organization for Educational Initiatives, University of Tsukuba (Japan)

    2014-07-01

    Rice plants exposed to radiation respond to the stress by activating self-defense mechanisms. A well-established molecular approach to measure stress is by cataloging global gene expression profiles. Here, we examined the effect of radiation exposure in a cereal crop model plant - rice (Oryza sativa L.) cultivar Nipponbare - in the village of Iitate of Fukushima prefecture. Iitate village is a highly radio-contaminated site due to the Fukushima Daiichi nuclear power plant accident following the Great East Japan Earthquake. The experimental approach comprised of five steps. First, healthy rice seedlings were grown in the greenhouse facility at National Institute for Environmental Sciences. Post-germination at 30 deg. C similarly germinated seeds were placed in neat rows in seedling pots having commercial soil (JA Zen-Noh, Japan; http//www.zennoh.or.jp/) with recommended NPK (nitrogen, phosphorus, and potash) doses at a controlled (25 deg. C, 70% relative humidity and natural light condition) greenhouse. Second, the seedlings were transported from a controlled greenhouse in Tsukuba to Iitate Farm (ITF) and placed, with no direct contact with soil, in a low-level gamma field where the rate of Cs-137 was 700 kBq/m{sup 2}. Third, exposure periods were set at 6, 12, 24, 48, and 72 h after arrival at ITF, and rice leaves at the 3. position (from the base) from 6 to 10 seedlings were sampled in dry ice. As control, rice leaves were sampled at the start in Tsukuba and immediately at arrival upon ITF; to know the radiation levels during growth and transport of the rice to ITF, accumulated radiation dose was calculated using a MYDOSE mini electronic pocket dosimeter (model PDM-222-52, ALOKA, Japan). A sample set was also taken at 72 h from healthy rice seedlings in the greenhouse at Tsukuba. All samples were stored at -80 deg. C. Accumulated total dose for exposed rice seedlings at 72 h was 200 mSv. Fourth, gene expression analysis was initiated by grinding the leaves to a

  7. The system of personal monitoring and the evaluation of occupational exposure to external ionizing radiation in Cuba

    International Nuclear Information System (INIS)

    Molina, Daniel; Castro, Ailza; Martinez, Ernesto; Pernas, Rene

    2008-01-01

    Full text: Personal monitoring of workers is recommended or required by the International Basic Safety Standards for Protection against Ionizing Radiation and for the Safety of Radiation Sources. In our country the personal monitoring of external exposure to ionizing radiation is carried out by External Dosimetry Laboratory (LDE) of the Center for Radiation Protection and Hygiene (CPHR). We have implemented an individual monitoring service based on thermoluminescence dosimetry system. The service includes whole body and extremity dosimeters. We have two systems; one is base on a manual Toledo TLD reader and the other on an automatic RADOS TLD system. This service is recognized by the National Regulatory Authority in the field of radiation protection and safety. We have implemented a quality assurance (QA) programme designed according to the recommendations of the ISO/IEC 17025 standards. The papers deals with the presentation of these QA programme which includes administrative data and information, technical checking of the equipment, acceptance tests of new dosimeters and equipment, issuing and processing of the dosimeters, dose evaluation, record keeping and reporting, traceability, handling of complaints, internal reviews and external audits. The papers also describe the results of occupational exposure for the different practices during 2006-2007 period. (author)

  8. Birth defects in Norway by levels of external and food-based exposure to radiation from Chernobyl

    International Nuclear Information System (INIS)

    Lie, R.T.; Irgens, L.M.; Skjaerven, R.; Reitan, J.B.; Strand, P.; Strand, T.

    1992-01-01

    In Norway, external doses of radiation resulting from fallout from the Chernobyl nuclear accident were estimated from detailed measurements, including soil deposition patterns. Internal doses were estimated from measurements of radioactive cesium in meat and milk supplies. The doses were calculated as average monthly doses for each of 454 municipalities during 36 consecutive months after the accident in spring 1986. Prospectively collected data on all newborns listed in the Medical Birth Registry of Norway who were conceived in the period May 1983-April 1989 were used to assess possible dose-response relations between estimated external and food-based exposures and congenital malformations and some other conditions. A positive association was observed between total radiation dose (external plus food-based) and hydrocephaly, while a negative association was observed for Down's syndrome. However, an important conclusion of the study was that no associations were found for conditions previously reported to be associated with radiation, i.e., small head circumference, congenital cataracts, anencephaly, spina bifida, and low birth weight. Potential sources of bias, including exposure misclassification and incomplete ascertainment of cases, are discussed

  9. Evaluation of the occupational exposure to external sources of ionizing radiation in Cuba in the period 2001-2005

    International Nuclear Information System (INIS)

    Molina P, D.; Martinez H, E.; Castro S, A.

    2006-01-01

    The single radiological surveillance of the occupational exposure to external radiation sources in Cuba it is carried out by the Radiation Protection and Hygiene Center (CPHR). The data corresponding to the external exposure are presented. The service it covers to all the occupationally exposed workers (TOEs) of the country that work fundamentally the radiodiagnostic practices, nuclear medicine, radiotherapy and research. The purpose of this work is to carry out an analysis of the occupational exposures of the TOE of the country starting of the results registered by the service of single radiological surveillance in the period 2001 to 2005, keeping in mind the indicators used by the UNSCEAR. The annual average effective dose (E) for each practice is shown. The obtained results showed that the values of annual average effective dose (E) its are bigger for the radiodiagnostic practices, radiotherapy and nuclear medicine. In a general way, all the E values are inferior to 2.00 mSv. The number of TOEs that overcame the 20 mSv established as annual dose limit, it went inferior to 1% of the controlled total universe. (Author)

  10. Temperament Moderates Associations between Exposure to Stress and Children's Externalizing Problems

    Science.gov (United States)

    Schermerhorn, Alice C.; Bates, John E.; Goodnight, Jackson A.; Lansford, Jennifer E.; Dodge, Kenneth A.; Pettit, Gregory S.

    2013-01-01

    The interaction between a temperament profile (four groups determined by high vs. low resistance to control [unmanageability] and unadaptability [novelty distress]) and family stress in predicting externalizing problems at school in children followed from kindergarten through eighth grade (ages 5-13) was investigated. The sample consisted of 556…

  11. Studies on occupational exposure to external radiation at Fukuoka University Hospital

    International Nuclear Information System (INIS)

    Miyauchi, Teiichi; Oshima, Yoshio; Ono, Yo

    1982-01-01

    This is a report of the yearly changes of exposure received by workers in radiological occupations at Fukuoka University Hospital from August 1973 to December 1980. The total number of the workers during this period involving diagnostic radiology, radiotherapy and the other related fields included 153 physicians, 27 technicians, 29 nurses and 16 assistants. Out of 225 workers, only two angiographers and two involved in intracavitary radiation therapy received more than 500 mrem of the annual exposure dose. The highest dose was 610 mrem. The exposure doses have gradually decreased each year. The exposure of the workers has remarkably decreased to almost negligible since a remote afterloading system was installed for intracavitary radiation therapy. In no worker was any somatic effect of radiation detected in the periodical physical examinations, even in the number of lymphocytes in the peripheral blood. (author)

  12. Studies on occupational exposure to external radiation at Fukuoka University Hospital

    Energy Technology Data Exchange (ETDEWEB)

    Miyauchi, Teiichi; Oshima, Yoshio; Ono, Yo [Fukuoka Univ. (Japan)

    1982-09-01

    This is a report of the yearly changes of exposure received by workers in radiological occupations at Fukuoka University Hospital from August 1973 to December 1980. The total number of the workers during this period involving diagnostic radiology, radiotherapy and the other related fields included 153 physicians, 27 technicians, 29 nurses and 16 assistants. Out of 225 workers, only two angiographers and two involved in intracavitary radiation therapy received more than 500 mrem of the annual exposure dose. The highest dose was 610 mrem. The exposure doses have gradually decreased each year. The exposure of the workers has remarkably decreased to almost negligible since a remote afterloading system was installed for intracavitary radiation therapy. In no worker was any somatic effect of radiation detected in the periodical physical examinations, even in the number of lymphocytes in the peripheral blood.

  13. A method, using ICRP 26 weighting factors, to determine effective dose equivalent due to nonuniform external exposures

    International Nuclear Information System (INIS)

    Dyer, S.G.

    1993-01-01

    Westinghouse Savannah River Company (WSRC) has recently implemented a methodology and supporting procedures to calculate effective dose equivalent for external exposures. The calculations are based on ICRP 26 methodology and are used to evaluate exposures when multibadging is used. The methodology is based upon the concept of open-quotes whole bodyclose quotes compartmentalization (i.e., the whole body is separated into seven specific regions of radiological concern and weighted accordingly). The highest dose measured in each compartment is used to determine the weighted dose to that compartment. Benefits of determining effective dose equivalent are compliance with DOE Orders, more accurate dose assessments, and the opportunity for improved worker protection through new ALARA opportunities

  14. Modeling residential exposure to secondhand tobacco smoke

    Science.gov (United States)

    Klepeis, Neil E.; Nazaroff, William W.

    We apply a simulation model to explore the effect of a house's multicompartment character on a nonsmoker's inhalation exposure to secondhand tobacco smoke (SHS). The model tracks the minute-by-minute movement of people and pollutants among multiple zones of a residence and generates SHS pollutant profiles for each room in response to room-specific smoking patterns. In applying the model, we consider SHS emissions of airborne particles, nicotine, and carbon monoxide in two hypothetical houses, one with a typical four-room layout and one dominated by a single large space. We use scripted patterns of room-to-room occupant movement and a cohort of 5000 activity patterns sampled from a US nationwide survey. The results for scripted and cohort simulation trials indicate that the multicompartment nature of homes, manifested as inter-room differences in pollutant levels and the movement of people among zones, can cause substantial variation in nonsmoker SHS exposure.

  15. Incorporating network externalities into the technology acceptance model

    NARCIS (Netherlands)

    Song, Michael; Parry, Mark E.; Kawakami, Tomoko

    2009-01-01

    Research on network externalities has identified a number of product categories in which the market performance of an innovation (e.g., unit sales and revenues) is an increasing function of that innovation's installed base and the availability of complementary products. Innovation scholars have

  16. External beam radiotherapy (EBRT) techniques used in breast cancer treatment to reduce cardiac exposure

    International Nuclear Information System (INIS)

    Fung, Esther; Hendry, Julie

    2013-01-01

    Radiotherapy in breast cancer treatment has been shown to reduce local recurrence and improve survival rates. However, there is a concern that breast radiotherapy can cause an increase in cardiac mortality, particularly in patients being treated for left-sided breast cancer. This review aims to investigate how cardiac exposure is minimised in breast radiotherapy and determine an optimal method for reducing cardiac dose, using literature from ScienceDirect, Medline and CINAHL. IMRT and breathing-adapted radiotherapy both reduce cardiac exposure but IMRT also increases the irradiated volume at low dose. Several issues were reported with regards to the clinical implementation of these techniques. It is suggested that inspiration breath-hold radiotherapy, is the preferred solution to minimising cardiac exposure but more research is warranted to confirm this. Long-term follow-up is required to determine dose–response relationships. Research needs to focus on breast cancer treatment as a whole in order to effectively reduce cardiac mortality.

  17. Childhood Maltreatment Exposure and Disruptions in Emotion Regulation: A Transdiagnostic Pathway to Adolescent Internalizing and Externalizing Psychopathology

    Science.gov (United States)

    Jenness, Jessica L.; Stoep, Ann Vander; McCauley, Elizabeth; McLaughlin, Katie A.

    2016-01-01

    Child maltreatment is a robust risk factor for internalizing and externalizing psychopathology in children and adolescents. We examined the role of disruptions in emotion regulation processes as a developmental mechanism linking child maltreatment to the onset of multiple forms of psychopathology in adolescents. Specifically, we examined whether child maltreatment was associated with emotional reactivity and maladaptive cognitive and behavioral responses to distress, including rumination and impulsive behaviors, in two separate samples. We additionally investigated whether each of these components of emotion regulation were associated with internalizing and externalizing psychopathology and mediated the association between child maltreatment and psychopathology. Study 1 included a sample of 167 adolescents recruited based on exposure to physical, sexual, or emotional abuse. Study 2 included a sample of 439 adolescents in a community-based cohort study followed prospectively for 5 years. In both samples, child maltreatment was associated with higher levels of internalizing psychopathology, elevated emotional reactivity, and greater habitual engagement in rumination and impulsive responses to distress. In Study 2, emotional reactivity and maladaptive responses to distress mediated the association between child maltreatment and both internalizing and externalizing psychopathology. These findings provide converging evidence for the role of emotion regulation deficits as a transdiagnostic developmental pathway linking child maltreatment with multiple forms of psychopathology. PMID:27695145

  18. Childhood Maltreatment Exposure and Disruptions in Emotion Regulation: A Transdiagnostic Pathway to Adolescent Internalizing and Externalizing Psychopathology.

    Science.gov (United States)

    Heleniak, Charlotte; Jenness, Jessica L; Stoep, Ann Vander; McCauley, Elizabeth; McLaughlin, Katie A

    2016-06-01

    Child maltreatment is a robust risk factor for internalizing and externalizing psychopathology in children and adolescents. We examined the role of disruptions in emotion regulation processes as a developmental mechanism linking child maltreatment to the onset of multiple forms of psychopathology in adolescents. Specifically, we examined whether child maltreatment was associated with emotional reactivity and maladaptive cognitive and behavioral responses to distress, including rumination and impulsive behaviors, in two separate samples. We additionally investigated whether each of these components of emotion regulation were associated with internalizing and externalizing psychopathology and mediated the association between child maltreatment and psychopathology. Study 1 included a sample of 167 adolescents recruited based on exposure to physical, sexual, or emotional abuse. Study 2 included a sample of 439 adolescents in a community-based cohort study followed prospectively for 5 years. In both samples, child maltreatment was associated with higher levels of internalizing psychopathology, elevated emotional reactivity, and greater habitual engagement in rumination and impulsive responses to distress. In Study 2, emotional reactivity and maladaptive responses to distress mediated the association between child maltreatment and both internalizing and externalizing psychopathology. These findings provide converging evidence for the role of emotion regulation deficits as a transdiagnostic developmental pathway linking child maltreatment with multiple forms of psychopathology.

  19. Comparison of External Exposure of Central and Eastern-European States as a Factor Threatening Financial Security of Their Economies

    Directory of Open Access Journals (Sweden)

    Magdalena Redo

    2018-06-01

    Full Text Available Central and Eastern-European countries are strongly linked to the international economic and financial systems, which results in their dependence on foreign capital and on the upturn in the global markets. This situation also makes them vulnerable to external shocks. Resilience of the economies of CEE countries was additionally diminished by their relatively quick and uncompromising opening up to the process of globalization and European integration. All the economies subject to scrutiny have quite a substantial external debt level (reaching 55–139% of GDP, their net international investment position is quite strongly in the negative (constituting 25–71% of GDP. They are also characterized by high level of foreign liabilities (85–350% of GDP, a significant degree of trade openness (export and import of goods and services amounting to 41–94% of GDP, considerable rate of foreign liquid portfolio investments (even as much as 32% of GDP. Another common feature is the strong financial support received from the EU budget, with CEE countries being its net beneficiaries (with the accumulated value of funds received from the EU budget in 2004–2015 at the level of 21–42% of GDP. It should be borne in mind that Lithuania, Latvia, Estonia, Slovenia and Slovakia are members of the Eurozone, i.e. operate an international currency, which improves their creditworthiness and augments the trust of the global markets. What seems not without significance for investors is the fact that the IMF classified these five CEE countries – as well as the Czech Republic – as advanced economies. In light of the above, it should be stated that the Polish economy is characterized by a relatively strong external exposure relative to the creditworthiness the country boasts. This exposure increases Poland’s vulnerability to shocks and makes it less immune thereto. These circumstances partially explain the higher estimation of the risk premium for investments in

  20. Guidelines for planning interventions against external exposure in industrial area after a nuclear accident. Pt. 2. Calculation of doses using Monte Carlo method

    International Nuclear Information System (INIS)

    Kis, Z.; Eged, K.; Meckbach, R.; Mueller, H.

    2003-01-01

    Countermeasures being different from the usual urban ones and largely applicable in industrial area are collected and evaluated in a separate report. The industrial area is defined here as such an area where productive and/or commercial activity is carried out. A good example is a supermarket or a factory. Based on the history of calculation models it is unambiguous that the Monte Carlo based simulation is the perspective to the dose assessment from external exposures in such a complex environment. A method of the calculation of doses from external exposures in urban-industrial environment is presented. Moreover, this report gives a summary about the time dependence of the source strengths relative to a reference surface and a short overview about the mechanical and chemical intervention techniques which can be applied in this area. Using a hypothetical scenario (a supermarket area contaminated by 137 Cs) the details of an exemplary calculation are given directly addressing the dose and averted dose blocks of the templates of industrial countermeasures. In addition, a sensitivity analysis of the results is presented. (orig.)

  1. 10 CFR Appendix C to Part 835 - Derived Air Concentration (DAC) for Workers From External Exposure During Immersion in a Cloud of...

    Science.gov (United States)

    2010-01-01

    ... Exposure During Immersion in a Cloud of Airborne Radioactive Material C Appendix C to Part 835 Energy... Concentration (DAC) for Workers From External Exposure During Immersion in a Cloud of Airborne Radioactive...-infinite cloud of airborne radioactive material. The DACs listed in this appendix may be modified to allow...

  2. Possible pathways between depression, emotional and external eating. A structural equation model.

    Science.gov (United States)

    Ouwens, Machteld A; van Strien, Tatjana; van Leeuwe, Jan F J

    2009-10-01

    Emotional and external eating appear to co-occur and both have been shown to correlate to neuroticism, especially depression. However, there is evidence suggesting that emotional and external eating are independent constructs. In this study we revisited the relation between depression, emotional, and external eating. Using structural equation modelling, we examined whether depression, emotional and external eating are directly related and also indirectly related through the intervening concepts alexithymia and impulsivity. Participants were 549 females concerned about their weight. They filled out instruments on emotional and external eating, depression, alexithymia, and impulse regulation. The relational structure between the model variables was explored for one half of the participants and this solution was checked using the other half. Our data showed a moderate relationship between emotional and external eating. Depression was positively and directly associated with emotional eating, but not with external eating. In addition, depression was indirectly related to emotional eating through both alexithymia and impulsivity. A significant relation was found between impulsivity and external eating. Results suggest potential mediating pathways between depression and emotional eating, while no relation appeared to exist between depression and external eating. Emotional and external eating would appear to be different constructs.

  3. EXPURT - a model for evaluating exposure from radioactive material deposited in the urban environment

    International Nuclear Information System (INIS)

    Crick, M.J.; Brown, J.

    1990-06-01

    This model, EXPURT (EXPosure from Urban Radionuclide Transfer), is described in detail. The model simulates the movement of activity deposited on various surfaces in the urban environment and, by taking into account the shielding properties of buildings and the habits of the population, evaluates the external doses to members of the population living in such urban environments, as a function of time after deposition. One of the other advantages of EXPURT over simpler models is that it can be used to assess the possible dose reductions that might be achieved by various decontamination techniques; for example, it can estimate the effectiveness of decontaminating roof surfaces alone in reducing exposure to individuals living in an urban environment. Sensitivity/uncertainty studies have been performed whereby those parameters contributing most to remaining uncertainty in the model's predictions of dose and dose rates were identified. Predictions of the EXPURT model were compared with those from a simpler external dose model in use at NRPB. (author)

  4. A TCP model for external beam treatment of intermediate-risk prostate cancer.

    LENUS (Irish Health Repository)

    Walsh, Seán

    2013-03-01

    Biological models offer the ability to predict clinical outcomes. The authors describe a model to predict the clinical response of intermediate-risk prostate cancer to external beam radiotherapy for a variety of fractionation regimes.

  5. Associations between prenatal cigarette smoke exposure and externalized behaviors at school age among Inuit children exposed to environmental contaminants.

    Science.gov (United States)

    Desrosiers, Caroline; Boucher, Olivier; Forget-Dubois, Nadine; Dewailly, Eric; Ayotte, Pierre; Jacobson, Sandra W; Jacobson, Joseph L; Muckle, Gina

    2013-01-01

    Smoking during pregnancy is common among Inuit women from the Canadian Arctic. Yet prenatal cigarette smoke exposure (PCSE) is seen as a major risk factor for childhood behavior problems. Recent data also suggest that co-exposure to neurotoxic environmental contaminants can exacerbate the effects of PCSE on behavior. This study examined the association between PCSE and behavior at school age in a sample of Inuit children from Nunavik, Québec, where co-exposure to environmental contaminants is also an important issue. Interactions with lead (Pb) and mercury (Hg), two contaminants associated with behavioral problems, were also explored. Participants were 271 children (mean age=11.3years) involved in a prospective birth-cohort study. PCSE was assessed through maternal recall. Assessment of child behavior was obtained from the child's classroom teacher on the Teacher Report Form (TRF) and the Disruptive Behavior Disorders Rating Scale (DBD). Exposure to contaminants was assessed from umbilical cord and child blood samples. Other confounders were documented by maternal interview. After control for contaminants and confounders, PCSE was associated with increased externalizing behaviors and attention problems on the TRF and higher prevalence of attention deficit hyperactivity disorder (ADHD) assessed on the DBD. No interactions were found with contaminants. This study extends the existing empirical evidence linking PCSE to behavioral problems in school-aged children by reporting these effects in a population where tobacco use is normative rather than marginal. Co-exposure to Pb and Hg do not appear to exacerbate tobacco effects, suggesting that these substances act independently. © 2013. Published by Elsevier Inc. All rights reserved.

  6. Study on external exposure doses from terrestrial radioactivity in Southern Vietnam

    International Nuclear Information System (INIS)

    Huy, N.Q.; Luyen, T.V.

    2012-01-01

    This paper presents the radioactivity concentrations of 226 Ra, 232 Th and 40 K for 106 samples of surface soil collected in Southern Vietnam. The mean values of mass activity of radionuclides 226 Ra, 232 Th and 40 K for Southern Vietnam are 28.6, 50.7 and 292.6 Bq kg -1 , respectively, which lead to the population-weighted absorbed dose rate of 54.5 nGy h -1 . The average annual effective doses outdoors, indoors and in total of Southern Vietnam are estimated to be 0.067, 0.374 and 0. 441 mSv, respectively. The radium equivalent activity and the external hazard index of soil in Southern Vietnam are in the range 23.2-254.1 Bq kg -1 and 0.06-0.69, respectively. (author)

  7. Study on external exposure doses from terrestrial radioactivity in Southern Vietnam

    International Nuclear Information System (INIS)

    Huy, N. Q.; Luyen, T. V.

    2006-01-01

    This paper presents the radioactivity concentrations of 226 Ra, 232 Th and 40 K for 106 samples of surface soil collected in Southern Vietnam. The mean values of mass activity of radionuclides 226 Ra, 232 Th and 40 K for Southern Vietnam are 28.6, 50.7 and 292.6 Bq kg -1 , respectively, which lead to the population-weighted absorbed dose rate of 54.5 nGy h -1 . The average annual effective doses outdoors, indoors and in total of Southern Vietnam are estimated to be 0.067, 0.374 and 0.441 mSv, respectively. The radium equivalent activity and the external hazard index of soil in Southern Vietnam are in the range 23.2-254.1 Bq kg -1 and 0.06-0.69, respectively. (authors)

  8. Benchmarking of computer codes and approaches for modeling exposure scenarios

    International Nuclear Information System (INIS)

    Seitz, R.R.; Rittmann, P.D.; Wood, M.I.; Cook, J.R.

    1994-08-01

    The US Department of Energy Headquarters established a performance assessment task team (PATT) to integrate the activities of DOE sites that are preparing performance assessments for the disposal of newly generated low-level waste. The PATT chartered a subteam with the task of comparing computer codes and exposure scenarios used for dose calculations in performance assessments. This report documents the efforts of the subteam. Computer codes considered in the comparison include GENII, PATHRAE-EPA, MICROSHIELD, and ISOSHLD. Calculations were also conducted using spreadsheets to provide a comparison at the most fundamental level. Calculations and modeling approaches are compared for unit radionuclide concentrations in water and soil for the ingestion, inhalation, and external dose pathways. Over 30 tables comparing inputs and results are provided

  9. Natural radiation external exposures levels in Chilean Sub-Antarctic and country stations

    International Nuclear Information System (INIS)

    Stuardo, E.

    1988-01-01

    Since 1983 gamma exposures levels, at 1,5 m above the soil are being investigated using TLD detectors. A network of 12 stations have been established from ARICA (18 deg 20' S latitude) in Northern Chile to YELCHO (64 deg 52' S latitude) in Antartic territory. One year monitoring period was used at Antartic stations and a four months period in the country. The main subject of this study is to assess the average background radiation levels along the territory which is relevant to get a reference level and specially an estimate of the average natural radiation contribution to the population dose in Southern Chile

  10. Estimated Internal and External Radiation Exposure of Caregivers of Patients With Pediatric Neuroblastoma Undergoing 131I Metaiodobenzylguanidine Therapy: A Prospective Pilot Study.

    Science.gov (United States)

    Han, Sangwon; Yoo, Seon Hee; Koh, Kyung-Nam; Lee, Jong Jin

    2017-04-01

    Current recommendations suggest that family members should participate in the care of children receiving in-hospital I metaiodobenzylguanidine (MIBG) therapy for neuroblastoma. The present study aimed to measure the external radiation exposure and estimate the internal radiation exposure of caregivers during the hospital stay for I MIBG therapy. Caregivers received radiation safety instructions and a potassium iodide solution for thyroid blockade before patient admission. External radiation exposure was determined using a personal pocket dosimeter. Serial 24-hour urine samples were collected from caregivers during the hospital stay. Estimated internal radiation exposure was calculated based on the urine activity. Twelve cases (mean age, 6.2 ± 3.5 years; range, 2-13 years) were enrolled. The mean administered activity was 233.3 ± 74.9 (range, 150.0-350.0) mCi. The mean external radiation dose was 5.8 ± 7.2 (range, 0.8-19.9) mSv. Caregivers of children older than 4 years had significantly less external radiation exposure than those of children younger than 4 years (1.9 ± 1.0 vs 16.4 ± 5.0 mSv; P = 0.012). The mean estimated internal radiation dose was 11.3 ± 10.2 (range, 1.0-29.8) μSv. Caregivers receive both external and internal radiation exposure while providing in-hospital care to children receiving I MIBG therapy for neuroblastoma. However, the internal radiation exposure was negligible compared with the external radiation exposure.

  11. Aspects of ICRP 60 and ICRU 47 relevant to individual monitoring of external exposure

    International Nuclear Information System (INIS)

    Dietze, G.; Menzel, H.G.

    1994-01-01

    Exposure limits recommended by the ICRP and used in regulations are expressed in risk related quantities such as effective dose or effective dose equivalent. Operational quantities such as ambient dose equivalent or personal dose equivalent are defined in phantoms and are designed to give reasonable estimates of exposure limiting quantities. The readings of individual dosemeters are calibrated in terms of operational quantities. The international commissions involved in the definition of risk related quantities (ICRP) and operational quantities (ICRU) have introduced various new definitions and modifications to previous quantities used in their respective publications ICRP 60 and ICRU 39, ICRU 47. The consequences of these alterations for the relationships between quantities within the hierarchy have to be examined and the new quantitative relationships (conversion coefficients) between basic physical radiation quantities such as particle fluence or air kerma and the new quantities have to be evaluated. In 1992, the ICRP and ICRU charged a joint task group with addressing these tasks with a view to revising ICRP Publication 51. This paper presents an outline for the subject of the report to be prepared by the task group. An introduction to the new phantom-based quantities is given and conceptional differences between the newly introduced and the previous quantities are discussed. (author)

  12. A Study on Ganui-Dae's External Form and Its Modeling for Ganui-Dae's External Form and Its Modeling for Restoration

    Science.gov (United States)

    Lee, Min-Soo; Lee, Yong Sam; Jeon, Jun Hyeok; Kim, Sang Hyuk

    2013-12-01

    Ganui-Dae, built in the reign of King Sejong, Joseon Dynasty, is a comprehensive observatory. It has various instruments for observation and time signal such as Ganui, Gyupyo(Gnomon), water-hammering type Honui and Honsang, and so on. Studying on Ganui-Dae has been focused on its location, history, criterion, etc, so far. However, studying on its external form and construction method has been conducted insufficiently. This study suggests the model for restoration of Ganui-Dae. The model is based on the analysis about external form of Ganui-Dae in various antique maps, and its construction method in those days.

  13. Duality in the U(1) Higgs model with an external field

    International Nuclear Information System (INIS)

    Damgaard, P.H.

    1988-07-01

    An external electromagnetic field is coupled to the lattice U(1) Higgs model in a Villain form. Duality transformations are then used to express the partition function in terms of an effective Lagrangian of topological excitations and their couplings to the external field. Consequences for the phase diagram are derived. (orig.)

  14. EXPOSURE ANALYSIS MODELING SYSTEM (EXAMS): USER MANUAL AND SYSTEM DOCUMENTATION

    Science.gov (United States)

    The Exposure Analysis Modeling System, first published in 1982 (EPA-600/3-82-023), provides interactive computer software for formulating aquatic ecosystem models and rapidly evaluating the fate, transport, and exposure concentrations of synthetic organic chemicals - pesticides, ...

  15. Summary of Building Protection Factor Studies for External Exposure to Ionizing Radiation

    Energy Technology Data Exchange (ETDEWEB)

    Dillon, Michael B. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Kane, Jave [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Nasstrom, John [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Homann, Steve [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Pobanz, Brenda [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2016-02-17

    Radiation dose assessments are used to help inform decisions to minimize health risks in the event of an atmospheric release of radioactivity including, for example, from a Radiological Dispersal Device, an Improvised Nuclear Device detonation, or a Nuclear Power Plant accident. During these incidents, radiation dose assessments for both indoor and outdoor populations are needed to make informed decisions. These dose assessments inform emergency plans and decisions including, for example, identifying areas in which people should be sheltered and determining when controlled population evacuations should be made. US dose assessment methodologies allow consideration of the protection, and therefore dose reduction, that buildings provide their occupants. However, these methodologies require an understanding of the protection provided by various building types that is currently lacking. To help address this need, Lawrence Livermore National Laboratory, in cooperation with Sandia National Laboratories and the Nuclear Regulatory Commission, was tasked with (a) identifying prior building protection studies, (b) extracting results relevant to US building construction, and (c) summarizing building protection by building type. This report focuses primarily on the protection against radiation from outdoor fallout particles (external gamma radiation).

  16. Summary of Building Protection Factor Studies for External Exposure to Ionizing Radiation

    International Nuclear Information System (INIS)

    Dillon, Michael B.; Kane, Jave; Nasstrom, John; Homann, Steve; Pobanz, Brenda

    2016-01-01

    Radiation dose assessments are used to help inform decisions to minimize health risks in the event of an atmospheric release of radioactivity including, for example, from a Radiological Dispersal Device, an Improvised Nuclear Device detonation, or a Nuclear Power Plant accident. During these incidents, radiation dose assessments for both indoor and outdoor populations are needed to make informed decisions. These dose assessments inform emergency plans and decisions including, for example, identifying areas in which people should be sheltered and determining when controlled population evacuations should be made. US dose assessment methodologies allow consideration of the protection, and therefore dose reduction, that buildings provide their occupants. However, these methodologies require an understanding of the protection provided by various building types that is currently lacking. To help address this need, Lawrence Livermore National Laboratory, in cooperation with Sandia National Laboratories and the Nuclear Regulatory Commission, was tasked with (a) identifying prior building protection studies, (b) extracting results relevant to US building construction, and (c) summarizing building protection by building type. This report focuses primarily on the protection against radiation from outdoor fallout particles (external gamma radiation).

  17. Electron dose-rate conversion factors for external exposure of the skin from uniformly deposited activity on the body surface

    International Nuclear Information System (INIS)

    Kocher, D.C.; Eckerman, K.F.

    1987-01-01

    Dose-rate conversion factors have been calculated for external exposure of the skin from electrons emitted by sources that are deposited uniformly on the body surface. The dose-rate factors are obtained from electron scaled point kernels developed by Berger. The dose-rate factors are calculated at depths of 4, 8, and 40 mg cm-2 below the body surface as recommended by Whitton, and at a depth of 7 mg cm-2 as recommended in ICRP Publication 26 (ICRP77). The dependence of the dose-rate factors at selected depths on the energy of the emitted electrons is displayed. The dose-rate factors for selected radionuclides of potential importance in radiological assessments are tabulated

  18. DEEP code to calculate dose equivalents in human phantom for external photon exposure by Monte Carlo method

    International Nuclear Information System (INIS)

    Yamaguchi, Yasuhiro

    1991-01-01

    The present report describes a computer code DEEP which calculates the organ dose equivalents and the effective dose equivalent for external photon exposure by the Monte Carlo method. MORSE-CG, Monte Carlo radiation transport code, is incorporated into the DEEP code to simulate photon transport phenomena in and around a human body. The code treats an anthropomorphic phantom represented by mathematical formulae and user has a choice for the phantom sex: male, female and unisex. The phantom can wear personal dosimeters on it and user can specify their location and dimension. This document includes instruction and sample problem for the code as well as the general description of dose calculation, human phantom and computer code. (author)

  19. Modeling Exposure of Mammalian Predatorsto Anticoagulant Rodenticides

    DEFF Research Database (Denmark)

    Topping, Christopher John; Elmeros, Morten

    2016-01-01

    as vectors of AR, and was used to evaluate likely impacts of restrictions imposed on AR use in Denmark banning the use of rodenticides for plant protection in woodlands and tree-crops. The model uses input based on frequencies and timings of baiting for rodent control for urban, rural and woodland locations......Anticoagulant rodenticides (AR) are a widespread and effective method of rodent control but there is concern about the impact these may have on non-target organisms, in particular secondary poisoning of rodent predators. Incidence and concentration of AR in free-living predators in Denmark is very...... high. We postulate that this is caused by widespread exposure due to widespread use of AR in Denmark in and around buildings. To investigate this theory a spatio-temporal model of AR use and mammalian predator distribution was created. This model was supported by data from an experimental study of mice...

  20. Doses of external exposure in Jordan house due to gamma-emitting natural radionuclides in building materials.

    Science.gov (United States)

    Al-Jundi, J; Ulanovsky, A; Pröhl, G

    2009-10-01

    The use of building materials containing naturally occurring radionuclides as (40)K, (232)Th, and (238)U and their progeny results in external exposures of the residents of such buildings. In the present study, indoor dose rates for a typical Jordan concrete room are calculated using Monte Carlo method. Uniform chemical composition of the walls, floor and ceiling as well as uniform mass concentrations of the radionuclides in walls, floor and ceiling are assumed. Using activity concentrations of natural radionuclides typical for the Jordan houses and assuming them to be in secular equilibrium with their progeny, the maximum annual effective doses are estimated to be 0.16, 0.12 and 0.22 mSv a(-1) for (40)K, (232)Th- and (238)U-series, respectively. In a total, the maximum annual effective indoor dose due to external gamma-radiation is 0.50 mSv a(-1). Additionally, organ dose coefficients are calculated for all organs considered in ICRP Publication 74. Breast, skin and eye lenses have the maximum equivalent dose rate values due to indoor exposures caused by the natural radionuclides, while equivalent dose rates for uterus, colon (LLI) and small intestine are found to be the smallest. More specifically, organ dose rates (nSv a(-1)per Bq kg(-1)) vary from 0.044 to 0.060 for (40)K, from 0.44 to 0.60 for radionuclides from (238)U-series and from 0.60 to 0.81 for radionuclides from (232)Th-series. The obtained organ and effective dose conversion coefficients can be conveniently used in practical dose assessment tasks for the rooms of similar geometry and varying activity concentrations and local-specific occupancy factors.

  1. Estimation of dose from exposure to external radiation in the environment

    International Nuclear Information System (INIS)

    Abe, Siro; Fujitaka, Kazunobu

    1978-01-01

    Meteorological factors which influence the external radiation were analysed. Attention was paid to the relationship between the concentration of the radioactive aerosol and the outdoor radiation level. Twelve kinds of data were obtained at Kumatori Site of Kyoto University. The mean diurnal variation and annual variation of each factors were obtained from the data of 25 months periods from August 1974 to August 1976. Outstanding was the result that the outdoor gamma radiation varied just slightly in spite of the large variation of the airborne activities and others. It implies that the individual effect due to the factor would compensate and cancel each other. Otherwise the major contribution on the variation might distribute at random with respect to time. Contrary to the apparent independence of the outdoor gamma radiation level of the airborne activity, however, the partial correlation coefficient between them was not negligibly small. Analysis of each time series of individual data has revealed that the rainfall has the largest influence on the variation of the outdoor gamma radiation level particularly in its initial period. Airborne activity was also revealed to have a strong connection with the atmospheric stability and the wind velocity though it depends on the rainfall just a little. The atmospheric stability could be expressed by the vertical gradient of the atmospheric temperature which is strongest at the ''inversion''. However problem remains as to the nature of the wind. Which of the atmospheric turbulence and the prevailing wind corresponds to the wind here will have to be analysed referring to the large scale weather charts. Regression analysis showed that the atmospheric temperature was the essential cause of the variation of the radiation level. (author)

  2. Comparative measurements of external radiation exposure using mobile phones, dental ceramic, household salt and conventional personal dosemeters

    International Nuclear Information System (INIS)

    Ekendahl, Daniela; Bulánek, Boris; Judas, Libor

    2015-01-01

    Because retrospective dosimetry utilises commonly occurring materials and objects, it is particularly useful in cases of large-scale radiation accidents or malevolent acts with radioactive materials where casualties are inflicted on the general public and first emergency responders. The aim of this study was to investigate whether retrospective dosemeters can provide dose estimates with comparable accuracy like conventional personal dosemeters. Using an external source of radiation 137 Cs and an anthropomorphic phantom, we simulated serious irradiation of a human body in anterior-posterior and rotational geometries. Retrospective luminescence dosimetry objects, such as mobile phones, dental ceramic and household salt, and conventional personal dosemeters (thermoluminescent and electronic) were fixed to the anthropomorphic phantom. The doses obtained were compared with specific reference values. In most cases, relative deviations between the measured doses and the reference values did not exceed 20%. As the retrospective and conventional dosemeters show no significant differences in laboratory conditions, the retrospective luminescence dosimetry objects represent a very promising tool if handled properly. - Highlights: • A serious external exposure of human body was simulated. • Doses were measured using both retrospective and conventional dosemeters. • Utilised retrospective dosimetry materials were alumina resistors from mobile phones, household salt and dental ceramic. • Doses obtained were compared with reference values. • Both retrospective and conventional dosemeters gave similar results

  3. Suggested Methods for Assessment of Accidental External Exposure and Internal Contamination of Workers and their Medical Management

    International Nuclear Information System (INIS)

    Mahmoud, K.A.; Morsy, Samira M.; Hanna, I.R.A.; Hafez, M.B.; Mohamed, H.O.; Jahns, E.; Saied, F.I.A.

    1969-01-01

    Certain assumptions are given for the amount of fission products released from a research reactor after the occurrence of an accident. The size and location of radioactive cloud are assumed, and the corresponding external and internal exposures of workers are computed. A method is suggested for assessment of accidental external radiation dose based on experimental studies performed on the changes of quenching effect of plasma or sera as a.result of whole- body gamma-radiation ranging from 25-200 rems. For assessment of accidentally internally incorporated gamma emitters we suggest the standard chair whole-body counter technique which was found to detect reliably 1/100 of the maximum permissible body burden within eight minutes. It was also suggested that a separation method based on the use of absorption phenomena observed for Sephadex (gel resin) can be applied for quick determination of gross alpha activity in urine. For management of accidentally exposed workers to radiation doses of a lethal or sublethal nature, bone-marrow transplantation therapy and blood component therapy in sterile rooms is discussed in the light of experience gained from treatment of leukaemia with intensive chemotherapy. (author)

  4. A Spatial Model of the Mere Exposure Effect.

    Science.gov (United States)

    Fink, Edward L.; And Others

    1989-01-01

    Uses a spatial model to examine the relationship between stimulus exposure, cognition, and affect. Notes that this model accounts for cognitive changes that a stimulus may acquire as a result of exposure. Concludes that the spatial model is useful for evaluating the mere exposure effect and that affective change does not require cognitive change.…

  5. DYNAMIC MATHEMATICAL MODEL OF URBAN SPATIAL PATTERN (RESIDENTIAL CHOICE OF LOCATION: MOBILITY VS EXTERNALITY

    Directory of Open Access Journals (Sweden)

    Rahma Fitriani

    2015-01-01

    Full Text Available Household’s residential choice of location determines urban spatial pattern (e.g sprawl. The static model which assumes that the choice has been affected by distance to the CBD and location specific externality, fails to capture the evoution of the pattern over time. Therefore this study proposes a dynamic version of the model. It analyses the effects of externalities on the optimal solution of development decision as function of time. It also derives the effect of mobility and externality on the rate of change of development pattern through time. When the increasing rate of utility is not as significant as the increasing rate of income, the externalities will delay the change of urban spatial pattern over time. If the mobility costs increase by large amount relative to the increase of income and inflation rate, then the mobility effect dominates the effects of externalities in delaying the urban expansion.

  6. Emotional inertia and external events: The roles of exposure, reactivity, and recovery.

    Science.gov (United States)

    Koval, Peter; Brose, Annette; Pe, Madeline L; Houben, Marlies; Erbas, Yasemin; Champagne, Dominique; Kuppens, Peter

    2015-10-01

    Increased moment-to-moment predictability, or inertia, of negative affect has been identified as an important dynamic marker of psychological maladjustment, and increased vulnerability to depression in particular. However, little is known about the processes underlying emotional inertia. The current article examines how the emotional context, and people's responses to it, are related to emotional inertia. We investigated how individual differences in the inertia of negative affect (NA) are related to individual differences in exposure, reactivity, and recovery from emotional events, in daily life (assessed using experience sampling) as well as in the lab (assessed using an emotional film-clip task), among 200 participants commencing their first year of tertiary education. This dual-method approach allowed us to assess affective responding on different timescales, and in response to standardized as well as idiographic emotional stimuli. Our most consistent finding, across both methods, was that heightened NA inertia is related to decreased NA recovery following negative stimuli, suggesting that higher levels of inertia may be mostly driven by impairments in affect repair following negative events. (c) 2015 APA, all rights reserved).

  7. Spatial Welfare Economics versus Ecological Footprint: Modeling Agglomeration, Externalities and Trade

    NARCIS (Netherlands)

    Grazi, F.; van den Bergh, J.C.J.M.; Rietveld, P.

    2007-01-01

    A welfare framework for the analysis of the spatial dimensions of sustainability is developed. It covers agglomeration effects, interregional trade, negative environmental externalities, and various land use categories. The model is used to compare rankings of spatial configurations according to

  8. The establishment of bilateral external iliac artery stenosis model in experimental canines and its angiographic evaluation

    International Nuclear Information System (INIS)

    Xia Yonghui; Li Weixiao; Bi Yonghua; Xu Ke

    2011-01-01

    Objective: To establish an experimental canine model of bilateral external iliac artery stenosis by surgical method with absorbable suture. Methods: Under general anesthesia bilateral external iliac arteries were partly obstructed (about 50%) with absorbable suture in ten dogs. Three months later angiography was performed to evaluate the arterial stricture degree. Results: Bilateral external iliac artery stenosis model was successfully established in eight dogs and the other two dogs died within two weeks after the procedure. Angiography performed three months after the procedure showed that the stricture degree of arterial lumen was (60.6±12.5)%. Conclusion: Satisfactory experimental canine model of bilateral external iliac artery stenosis can be established by surgical method with absorbable suture. This method can be used for reference when peripheral artery stenosis model is to be prepared in larger animals. (authors)

  9. Evaluation of eleven years of area monitoring in ore treatment unit: I external exposure

    Energy Technology Data Exchange (ETDEWEB)

    Pereira, W.S.; Py Junior, D.A.; Oliveira, S.Q. de; Dantas, M.V.A., E-mail: pereiraws@gmail.com [Industrias Nucleares do Brasil (INB), Pocos de Caldas, MG (Brazil). Unidade de Tratamento de Minerio. Grupo Multidisciplinar de Radioprotecao; Kelecom, A., E-mail: akelecom@id.uff.br [Universidade Federal Fluminense (LARARA-PLS/GETA/UFF), Niteroi, RJ (Brazil). Laboratorio de Radiobiologia e Radiometria Pedro Lopes dos Santos. Grupo de Estudos em Temas Ambientais; Pereira, J.R.S., E-mail: pereirarsj@gmail.com [Universidade Federal de Alfenas (UNIFAL), Pocos de Caldas, MG (Brazil)

    2013-07-01

    The Ore Treatment Unit (OTU) is an uranium mining and milling complex deactivated in 1995 that operated monazite during the years 2004 and 2005 in a plant used especially for that purpose called Chemical Treatment of Monazite (CTM). This study aims to analyze the monitoring of area to exposure rate from 2002 to 2012, comparing periods of suspended operation of OTU and identifying the influences of CTM and of the radioactive waste deposit, from other facilities of OTU. A total of 22,294 samples were analyzed for area dose rates; average values were obtained of 6.74 μSv h{sup -1} with an amplitude from 0 to 420 μSv h{sup -1}. 92% of the monitoring were below the derivative limit for workers, and 1,702 monitoring samples showed values above this limit. Ignoring the monitoring that was realized at CTM and at the deposit of radioactive waste, the number of monitoring samples were reduced to 1,341. In this case, the average reduces to 0.96 μSv h{sup -1}, going from 0 to 25 μSv h{sup -1}, only 15 samples remained above the threshold for workers and 675 samples were below the limit for individual public. It can be concluded that the OTU is an installation with nearly 99% of monitoring area safe for workers and 50% for individual public. The inclusion of new practices (CTM) and the deposit of radioactive waste coming from other facilities alter this picture dramatically, increased the dose rates. (author)

  10. Task-based dermal exposure models for regulatory risk assessment.

    Science.gov (United States)

    Warren, Nicholas D; Marquart, Hans; Christopher, Yvette; Laitinen, Juha; VAN Hemmen, Joop J

    2006-07-01

    The regulatory risk assessment of chemicals requires the estimation of occupational dermal exposure. Until recently, the models used were either based on limited data or were specific to a particular class of chemical or application. The EU project RISKOFDERM has gathered a considerable number of new measurements of dermal exposure together with detailed contextual information. This article describes the development of a set of generic task-based models capable of predicting potential dermal exposure to both solids and liquids in a wide range of situations. To facilitate modelling of the wide variety of dermal exposure situations six separate models were made for groupings of exposure scenarios called Dermal Exposure Operation units (DEO units). These task-based groupings cluster exposure scenarios with regard to the expected routes of dermal exposure and the expected influence of exposure determinants. Within these groupings linear mixed effect models were used to estimate the influence of various exposure determinants and to estimate components of variance. The models predict median potential dermal exposure rates for the hands and the rest of the body from the values of relevant exposure determinants. These rates are expressed as mg or microl product per minute. Using these median potential dermal exposure rates and an accompanying geometric standard deviation allows a range of exposure percentiles to be calculated.

  11. Markov model of the loan portfolio dynamics considering influence of management and external economic factors

    Science.gov (United States)

    Bozhalkina, Yana; Timofeeva, Galina

    2016-12-01

    Mathematical model of loan portfolio in the form of a controlled Markov chain with discrete time is considered. It is assumed that coefficients of migration matrix depend on corrective actions and external factors. Corrective actions include process of receiving applications, interaction with existing solvent and insolvent clients. External factors are macroeconomic indicators, such as inflation and unemployment rates, exchange rates, consumer price indices, etc. Changes in corrective actions adjust the intensity of transitions in the migration matrix. The mathematical model for forecasting the credit portfolio structure taking into account a cumulative impact of internal and external changes is obtained.

  12. A preventive maintenance model for leased equipment subject to internal degradation and external shock damage

    International Nuclear Information System (INIS)

    Zhou, Xiaojun; Wu, Changjie; Li, Yanting; Xi, Lifeng

    2016-01-01

    A periodic preventive maintenance modeling method is proposed for leased equipment with continuous internal degradation and stochastic external shock damage considered simultaneously, which can facilitate the equipment lessor to optimize the maintenance schedule for the same kind of equipment rented by different lessees. A novel interactive mechanism between the continuous internal degradation and the stochastic external shock damage is established on the hazard rate of the equipment with integrating the imperfect effect of maintenance. Two improvement factors are defined for the modeling of imperfect maintenance. The number of failures resulting from internal degradation and from external shocks are both mathematically deduced based on this interactive mechanism. The optimal preventive maintenance scheme is obtained by minimizing the cumulative maintenance cost throughout the lease period. Numerical example shows that the proposed preventive maintenance model not only can reflect the reliability status of the equipment but also can clearly distinguish between the impact from internal degradation and that from external shocks. - Highlights: • We propose an imperfect periodic preventive maintenance model for leased equipment. • It can distinguish between the impact from internal degradation and that from external shocks. • An internal–external interactive mechanism is proposed. • Two improvement factors are introduced into the modeling of imperfect maintenance. • The model is helpful for the PM scheduling of the same equipment rented by different lessees.

  13. Chromosome aberrations in workers with exposure to α-particle radiation from internal deposits of plutonium: expectations from in vitro studies and comparisons with workers with predominantly external γ-radiation exposure

    Energy Technology Data Exchange (ETDEWEB)

    Curwen, Gillian B.; Tawn, E.J. [The University of Manchester, Centre for Integrated Genomic Medical Research (CIGMR), School of Population Health, Faculty of Medical and Human Sciences, Manchester (United Kingdom); Sotnik, Natalia V.; Azizova, Tamara V. [Southern Urals Biophysics Institute (SUBI), Ozyorsk, Chelyabinsk Region 456780 (Russian Federation); Cadwell, Kevin K. [Medical School, Newcastle University, Institute for Cell and Molecular Biosciences, Newcastle upon Tyne (United Kingdom); Hill, Mark A. [University of Oxford, CRUK/MRC Oxford Institute for Radiation Oncology, Gray Laboratories, Oxford (United Kingdom)

    2015-05-15

    mFISH analysis of chromosome aberration profiles of 47 and 144 h lymphocyte cultures following exposure to 193 mGy α-particle radiation confirmed that the frequency of stable aberrant cells and stable cells carrying translocations remains constant through repeated cell divisions. Age-specific rates and in vitro dose-response curves were used to derive expected translocation yields in nine workers from the Mayak nuclear facility in Russia. Five had external exposure to γ-radiation, two of whom also had exposure to neutrons, and four had external exposure to γ-radiation and internal exposure to α-particle radiation from incorporated plutonium. Doubts over the appropriateness of the dose response used to estimate translocations from the neutron component made interpretation difficult in two of the workers with external exposure, but the other three had translocation yields broadly in line with expectations. Three of the four plutonium workers had translocation yields in line with expectations, thus supporting the application of the recently derived in vitro α-particle dose response for translocations in stable cells. Overall this report demonstrates that with adequate reference in vitro dose-response curves, translocation yield has the potential to be a useful tool in the validation of red bone marrow doses resulting from mixed exposure to external and internal radiation. (orig.)

  14. Prediction models for successful external cephalic version: a systematic review

    NARCIS (Netherlands)

    Velzel, Joost; de Hundt, Marcella; Mulder, Frederique M.; Molkenboer, Jan F. M.; van der Post, Joris A. M.; Mol, Ben W.; Kok, Marjolein

    2015-01-01

    To provide an overview of existing prediction models for successful ECV, and to assess their quality, development and performance. We searched MEDLINE, EMBASE and the Cochrane Library to identify all articles reporting on prediction models for successful ECV published from inception to January 2015.

  15. The Roles of Family and Teacher Support in Moderating and Mediating Externalized and Internalized Outcomes of Exposure to Community Violence Among Arab and Jewish Adolescents in Israel.

    Science.gov (United States)

    Haj-Yahia, Muhammad M; Leshem, Becky; Guterman, Neil B

    2018-02-01

    The study examined family and teacher support as factors that can protect adolescents from internalized and externalized problems after exposure to community violence (ECV). Self-administered questionnaires were filled out by a sample of 1,832 Arab and Jewish Israeli high school students. The Arab adolescents reported significantly higher levels of community violence victimization, internalized problems, externalized problems, family support, and teacher support than the Jewish adolescents. The girls reported higher levels of internalized problems, and the boys reported higher levels of externalized problems. ECV predicted high levels of internalized and externalized problems, family support predicted low levels of internalized and externalized problems, and teacher support had no predictive role. Path analysis confirmed the significance of the relationships between ECV effects, support variables, and gender. The limitations of the study and implications of the findings for future research and for the development of family care and family intervention programs are discussed.

  16. SCROLL, a superconfiguration collisional radiative model with external radiation

    International Nuclear Information System (INIS)

    Bar-Shalom, A.; Oreg, J.; Klapisch, M.

    2000-01-01

    A collisional radiative model for calculating non-local thermodynamical-equilibrium (non-LTE) spectra of heavy atoms in hot plasmas has been developed. It takes into account the numerous excited an autoionizing states by using superconfigurations. These are split systematically until the populations converge. The influence of an impinging radiation field has recently been added to the model. The effect can be very important. (author)

  17. Gauge-independent decoherence models for solids in external fields

    Science.gov (United States)

    Wismer, Michael S.; Yakovlev, Vladislav S.

    2018-04-01

    We demonstrate gauge-invariant modeling of an open system of electrons in a periodic potential interacting with an optical field. For this purpose, we adapt the covariant derivative to the case of mixed states and put forward a decoherence model that has simple analytical forms in the length and velocity gauges. We demonstrate our methods by calculating harmonic spectra in the strong-field regime and numerically verifying the equivalence of the deterministic master equation to the stochastic Monte Carlo wave-function method.

  18. AirPEx: Air Pollution Exposure Model

    NARCIS (Netherlands)

    Freijer JI; Bloemen HJTh; Loos S de; Marra M; Rombout PJA; Steentjes GM; Veen MP van; LBO

    1997-01-01

    Analysis of inhalatory exposure to air pollution is an important area of investigation when assessing the risks of air pollution for human health. Inhalatory exposure research focuses on the exposure of humans to air pollutants and the entry of these pollutants into the human respiratory tract. The

  19. Dynamic Delayed Duplicate Detection for External Memory Model Checking

    DEFF Research Database (Denmark)

    Evangelista, Sami

    2008-01-01

    Duplicate detection is an expensive operation of disk-based model checkers. It consists of comparing some potentially new states, the candidate states, to previous visited states. We propose a new approach to this technique called dynamic delayed duplicate detection. This one exploits some typical...

  20. Modeling of active control of external magnetohydrodynamic instabilities

    International Nuclear Information System (INIS)

    Bialek, James; Boozer, Allen H.; Mauel, M.E.; Navratil, G.A.

    2001-01-01

    A general circuit formulation of resistive wall mode (RWM) feedback stabilization developed by Boozer [Phys. Plasmas 5, 3350 (1998)] has been used as the basis for the VALEN computer code that calculates the performance of an active control system in arbitrary geometry. The code uses a finite element representation of a thin shell structure in an integral formulation to model arbitrary conducting walls. This is combined with a circuit representation of stable and unstable plasma modes. Benchmark comparisons of VALEN results with large aspect ratio analytic model of the current driven kink mode are in very good agreement. VALEN also models arbitrary sensors, control coils, and the feedback logic connecting these sensors and control coils to provide a complete simulation capability for feedback control of plasma instabilities. VALEN modeling is in good agreement with experimental results on DIII-D [Garofalo et al., Nucl. Fusion 40, 1491 (2000)] and HBT-EP [Cates et al., Phys. Plasmas 7, 3133 (2000)]. VALEN feedback simulations have also been used to evaluate and optimize the sensor/coil configurations for present and planned RWM experiments on DIII-D. These studies have shown a clear advantage for the use of local poloidal field sensors driving a 'mode control' feedback logic control loop and configurations which minimize the control coil coupling to the stabilizing resistive wall

  1. Dynamic Delayed Duplicate Detection for External Memory Model Checking

    DEFF Research Database (Denmark)

    Evangelista, Sami

    2008-01-01

    Duplicate detection is an expensive operation of disk-based model checkers. It consists of comparing some potentially new states, the candidate states, to previous visited states. We propose a new approach to this technique called dynamic delayed duplicate detection. This one exploits some typica...... significantly better than some previously published algorithms....

  2. Effect of external fields in Axelrod's model of social dynamics

    Science.gov (United States)

    Peres, Lucas R.; Fontanari, José F.

    2012-09-01

    The study of the effects of spatially uniform fields on the steady-state properties of Axelrod's model has yielded plenty of counterintuitive results. Here, we reexamine the impact of this type of field for a selection of parameters such that the field-free steady state of the model is heterogeneous or multicultural. Analyses of both one- and two-dimensional versions of Axelrod's model indicate that the steady state remains heterogeneous regardless of the value of the field strength. Turning on the field leads to a discontinuous decrease on the number of cultural domains, which we argue is due to the instability of zero-field heterogeneous absorbing configurations. We find, however, that spatially nonuniform fields that implement a consensus rule among the neighborhood of the agents enforce homogenization. Although the overall effects of the fields are essentially the same irrespective of the dimensionality of the model, we argue that the dimensionality has a significant impact on the stability of the field-free homogeneous steady state.

  3. Report 2: Guidance document on practices to model and implement external flooding hazards in extended PSA

    International Nuclear Information System (INIS)

    Rebour, V.; Georgescu, G.; Leteinturier, D.; Raimond, E.; La Rovere, S.; Bernadara, P.; Vasseur, D.; Brinkman, H.; Groudev, P.; Ivanov, I.; Turschmann, M.; Sperbeck, S.; Potempski, S.; Hirata, K.; Kumar, Manorma

    2016-01-01

    This report provides a review of existing practices to model and implement external flooding hazards in existing level 1 PSA. The objective is to identify good practices on the modelling of initiating events (internal and external hazards) with a perspective of development of extended PSA and implementation of external events modelling in extended L1 PSA, its limitations/difficulties as far as possible. The views presented in this report are based on the ASAMPSA-E partners' experience and available publications. The report includes discussions on the following issues: - how to structure a L1 PSA for external flooding events, - information needed from geosciences in terms of hazards modelling and to build relevant modelling for PSA, - how to define and model the impact of each flooding event on SSCs with distinction between the flooding protective structures and devices and the effect of protection failures on other SSCs, - how to identify and model the common cause failures in one reactor or between several reactors, - how to apply HRA methodology for external flooding events, - how to credit additional emergency response (post-Fukushima measures like mobile equipment), - how to address the specific issues of L2 PSA, - how to perform and present risk quantification. (authors)

  4. Boundary diffraction wave integrals for diffraction modeling of external occulters

    OpenAIRE

    Cady, E.

    2012-01-01

    An occulter is a large diffracting screen which may be flown in conjunction with a telescope to image extrasolar planets. The edge is shaped to minimize the diffracted light in a region beyond the occulter, and a telescope may be placed in this dark shadow to view an extrasolar system with the starlight removed. Errors in position, orientation, and shape of the occulter will diffract additional light into this region, and a challenge of modeling an occulter system is to accurately and quickly...

  5. Computer tomography of flows external to test models

    Science.gov (United States)

    Prikryl, I.; Vest, C. M.

    1982-01-01

    Computer tomographic techniques for reconstruction of three-dimensional aerodynamic density fields, from interferograms recorded from several different viewing directions were studied. Emphasis is on the case in which an opaque object such as a test model in a wind tunnel obscures significant regions of the interferograms (projection data). A method called the Iterative Convolution Method (ICM), existing methods in which the field is represented by a series expansions, and analysis of real experimental data in the form of aerodynamic interferograms are discussed.

  6. The relationships between internal and external training load models during basketball training.

    Science.gov (United States)

    Scanlan, Aaron T; Wen, Neal; Tucker, Patrick S; Dalbo, Vincent J

    2014-09-01

    The present investigation described and compared the internal and external training loads during basketball training. Eight semiprofessional male basketball players (mean ± SD, age: 26.3 ± 6.7 years; stature: 188.1 ± 6.2 cm; body mass: 92.0 ± 13.8 kg) were monitored across a 7-week period during the preparatory phase of the annual training plan. A total of 44 total sessions were monitored. Player session ratings of perceived exertion (sRPE), heart rate, and accelerometer data were collected across each training session. Internal training load was determined using the sRPE, training impulse (TRIMP), and summated-heart-rate-zones (SHRZ) training load models. External training load was calculated using an established accelerometer algorithm. Pearson product-moment correlations with 95% confidence intervals (CIs) were used to determine the relationships between internal and external training load models. Significant moderate relationships were observed between external training load and the sRPE (r42 = 0.49, 95% CI = 0.23-0.69, p external training load and the SHRZ model (r42 = 0.61, 95% CI = 0.38-0.77, p internal and external training load models, the magnitude of the correlations and low commonality suggest that internal training load models measure different constructs of the training process than the accelerometer training load model in basketball settings. Basketball coaching and conditioning professionals should not assume a linear dose-response between accelerometer and internal training load models during training and are recommended to combine internal and external approaches when monitoring training load in players.

  7. Modeling Exposure to Heat Stress with a Simple Urban Model

    Directory of Open Access Journals (Sweden)

    Peter Hoffmann

    2018-01-01

    Full Text Available As a first step in modeling health-related urban well-being (UrbWellth, a mathematical model is constructed that dynamically simulates heat stress exposure of commuters in an idealized city. This is done by coupling the Simple Urban Radiation Model (SURM, which computes the mean radiant temperature ( T m r t , with a newly developed multi-class multi-mode traffic model. Simulation results with parameters chosen for the city of Hamburg for a hot summer day show that commuters are potentially most exposed to heat stress in the early afternoon when T m r t has its maximum. Varying the morphology with respect to street width and building height shows that a more compact city configuration reduces T m r t and therefore the exposure to heat stress. The impact resulting from changes in the city structure on traffic is simulated to determine the time spent outside during the commute. While the time in traffic jams increases for compact cities, the total commuting time decreases due to shorter distances between home and work place. Concerning adaptation measures, it is shown that increases in the albedo of the urban surfaces lead to an increase in daytime heat stress. Dramatic increases in heat stress exposure are found when both, wall and street albedo, are increased.

  8. On modelling adiabatic N-soliton interactions and perturbations. Effects of external potentials

    International Nuclear Information System (INIS)

    Gerdjikov, V.; Baizakov, B.

    2005-01-01

    We analyze several perturbed versions of the complex Toda chain (CTC) in an attempt to describe the adiabatic N-soliton train interactions of the perturbed nonlinear Schrodinger equation (NLS). Particular types of perturbations, including quadratic and periodic external potentials are treated by both analytical and numerical means. We show that the perturbed CTC model provides a good description for the N-soliton interactions in the presence of a weak external potential. (authors)

  9. Parametric Variation for Detailed Model of External Grid in Offshore Wind Power Plants

    DEFF Research Database (Denmark)

    Myagkov, Vladimir; Petersen, Lennart; Laza, Burutxaga

    2014-01-01

    The representation of the external grid impedance is a key element in harmonic studies for offshore wind farms. The external grid impedance is here represented by two different approaches: by a simplified impedance model, based on values for short-circuit power and XR-ratio and by locus diagrams...... for defining a procedure for conducting harmonic studies in wind farms that can be used in commercial project developments....

  10. Chiral symmetry breaking in d=3 NJL model in external gravitational and magnetic fields

    OpenAIRE

    Gitman, D. M.; Odintsov, S. D.; Shil'nov, Yu. I.

    1996-01-01

    The phase structure of $d=3$ Nambu-Jona-Lasinio model in curved spacetime with magnetic field is investigated in the leading order of the $1/N$-expansion and in linear curvature approximation (an external magnetic field is treated exactly). The possibility of the chiral symmetry breaking under the combined action of the external gravitational and magnetic fields is shown explicitly. At some circumstances the chiral symmetry may be restored due to the compensation of the magnetic field by the ...

  11. Modeling Attitude towards Drug Treament: The Role of Internal Motivation, External Pressure, and Dramatic Relief

    OpenAIRE

    Conner, Bradley T.; Longshore, Douglas; Anglin, M. Douglas

    2008-01-01

    Motivation for change has historically been viewed as the crucial element affecting responsiveness to drug treatment. Various external pressures, such as legal coercion, may engender motivation in an individual previously resistant to change. Dramatic relief may be the change process that is most salient as individuals internalize such external pressures. Results of structural equation modeling on data from 465 drug users (58.9% male; 21.3% Black, 34.2% Hispanic/Latino, and 35.1% White) enter...

  12. Typologies of intimate partner violence-maternal parenting and children's externalizing problems: The moderating effect of the exposure to other forms of family violence.

    Science.gov (United States)

    Lamela, Diogo; Jongenelen, Inês; Pinto, Ricardo; Levendosky, Alytia

    2018-07-01

    Typologies of IPV and parenting practices in mothers who experienced police-reported IPV remain surprisingly unexplored, in addition to how those typologies are linked with children's externalizing problems. Using data from 162 Portuguese mother-child dyads with a police or child protection services referral of IPV, this study aimed to: (a) identify IPV-parenting typologies; (b) test the associations between typologies and children's externalizing problems, and (c) examine the moderating effect of children's exposure to other forms of family violence in those associations. Using a person-centered approach, two IPV-parenting typologies were found: a spillover typology, with high levels of physical, psychological, and sexual violence and high levels of harsh and inconsistent parenting practices; and a compartmentalized typology, with high levels of physical, psychological, and sexual violence and lower ineffective parenting practices. Results also showed that externalizing symptoms (reported by mothers and teachers) were significantly lower in children of mothers in the compartmentalized typology compared to those in the spillover typology. Children's direct exposure to other forms of family violence moderated this association. Findings suggested that children with a high exposure to other forms of family violence showed the highest levels of externalizing problems when their mothers were classified into the spillover typology, and they exhibited the lowest levels of externalizing problems when their mothers were classified in the compartmentalized typology. Copyright © 2018 Elsevier Ltd. All rights reserved.

  13. Air Pollution Exposure Modeling for Health Studies | Science ...

    Science.gov (United States)

    Dr. Michael Breen is leading the development of air pollution exposure models, integrated with novel personal sensor technologies, to improve exposure and risk assessments for individuals in health studies. He is co-investigator for multiple health studies assessing the exposure and effects of air pollutants. These health studies include participants with asthma, diabetes, and coronary artery disease living in various U.S. cities. He has developed, evaluated, and applied novel exposure modeling and time-activity tools, which includes the Exposure Model for Individuals (EMI), GPS-based Microenvironment Tracker (MicroTrac) and Exposure Tracker models. At this seminar, Dr. Breen will present the development and application of these models to predict individual-level personal exposures to particulate matter (PM) for two health studies in central North Carolina. These health studies examine the association between PM and adverse health outcomes for susceptible individuals. During Dr. Breen’s visit, he will also have the opportunity to establish additional collaborations with researchers at Harvard University that may benefit from the use of exposure models for cohort health studies. These research projects that link air pollution exposure with adverse health outcomes benefit EPA by developing model-predicted exposure-dose metrics for individuals in health studies to improve the understanding of exposure-response behavior of air pollutants, and to reduce participant

  14. Estimating Margin of Exposure to Thyroid Peroxidase Inhibitors Using High-Throughput in vitro Data, High-Throughput Exposure Modeling, and Physiologically Based Pharmacokinetic/Pharmacodynamic Modeling

    Science.gov (United States)

    Leonard, Jeremy A.; Tan, Yu-Mei; Gilbert, Mary; Isaacs, Kristin; El-Masri, Hisham

    2016-01-01

    Some pharmaceuticals and environmental chemicals bind the thyroid peroxidase (TPO) enzyme and disrupt thyroid hormone production. The potential for TPO inhibition is a function of both the binding affinity and concentration of the chemical within the thyroid gland. The former can be determined through in vitro assays, and the latter is influenced by pharmacokinetic properties, along with environmental exposure levels. In this study, a physiologically based pharmacokinetic (PBPK) model was integrated with a pharmacodynamic (PD) model to establish internal doses capable of inhibiting TPO in relation to external exposure levels predicted through exposure modeling. The PBPK/PD model was evaluated using published serum or thyroid gland chemical concentrations or circulating thyroxine (T4) and triiodothyronine (T3) hormone levels measured in rats and humans. After evaluation, the model was used to estimate human equivalent intake doses resulting in reduction of T4 and T3 levels by 10% (ED10) for 6 chemicals of varying TPO-inhibiting potencies. These chemicals were methimazole, 6-propylthiouracil, resorcinol, benzophenone-2, 2-mercaptobenzothiazole, and triclosan. Margin of exposure values were estimated for these chemicals using the ED10 and predicted population exposure levels for females of child-bearing age. The modeling approach presented here revealed that examining hazard or exposure alone when prioritizing chemicals for risk assessment may be insufficient, and that consideration of pharmacokinetic properties is warranted. This approach also provides a mechanism for integrating in vitro data, pharmacokinetic properties, and exposure levels predicted through high-throughput means when interpreting adverse outcome pathways based on biological responses. PMID:26865668

  15. Basis for calculating body equivalent doses after external radiation exposure. 3. rev. and enl. ed.; Berechnungsgrundlage fuer die Ermittlung von Koerper-Aequivalentdosen bei aeusserer Strahlenexposition

    Energy Technology Data Exchange (ETDEWEB)

    Sarenio, O. (comp.) [Geschaeftsstelle der Strahlenschutzkommission beim Bundesamt fuer Strahlenschutz, Bonn (Germany)

    2017-07-01

    The book on the basis for calculating body equivalent doses after external radiation exposure includes the following issues: introduction covering the scope of coverage and body equivalent doses for radiation protection, terminology, photon radiation, neutron radiation, electron radiation, mixed radiation fields and the estimation of body equivalent doses for skin surface contamination.

  16. Mathematical modelling of a human external respiratory system

    Science.gov (United States)

    1977-01-01

    A closed system of algebraic and common differential equations solved by computer is investigated. It includes equations which describe the activity pattern of the respiratory center, the phrenic nerve, the thrust produced by the diaphragm as a function of the lung volume and discharge frequency of the phrenic nerve, as well as certain relations of the lung stretch receptors and chemoreceptors on various lung and blood characteristics, equations for lung biomechanics, pulmonary blood flow, alveolar gas exchange and capillary blood composition equations to determine various air and blood flow and gas exchange parameters, and various gas mixing and arterial and venous blood composition equations, to determine other blood, air and gas mixing characteristics. Data are presented by means of graphs and tables, and some advantages of this model over others are demonstrated by test results.

  17. Coupling of the FLake model to the Surfex externalized surface model

    Energy Technology Data Exchange (ETDEWEB)

    Salgado, R. (Univ. of Evora, Centro de Geofisica de Evora (Portugal)); Le Moigne, P. (CNRM/GAME, Meteo-France/CNRS, Toulouse (France))

    2010-07-01

    The FLake model parameterizes the local-scale energy exchanges between lake surfaces and the atmosphere. FLake simulates the temperature profile as well as the budgets of heat and turbulent kinetic energy in water. Its implementation into the Surfex system, the externalized surface scheme devoted to research and operational forecasts, is presented here. The paper describes a validation of the coupled system Surfex-FLake based on measurements carried out on the Alqueva reservoir in southern Portugal. This paper shows how the use of FLake in the Surfex system improves surface temperature and turbulent fluxes at the water-atmosphere interface and explains the minor changes made in the computation of the shape function in order to adapt the FLake model to warm lakes, like the one used for this study. (orig.)

  18. Posttraumatic Stress, Family Functioning, and Externalizing in Adolescents Exposed to Violence: A Moderated Mediation Model.

    Science.gov (United States)

    Deane, Kyle; Richards, Maryse; Mozley, Michaela; Scott, Darrick; Rice, Catherine; Garbarino, James

    2016-09-02

    Exposure to community violence disproportionately impacts low-income, minority youth and is associated with posttraumatic stress symptoms and maladaptive adjustment. This study investigates whether posttraumatic stress mediates the relation between exposure to community violence and externalizing symptoms and the moderating role of family cohesion and daily family support in buffering these effects on later externalizing. Low-income, African American 7th-grade students (M age = 12.57 years; N = 254) from high-crime neighborhoods participated in a 2-year longitudinal study measuring the effects of community violence exposure. The students completed questionnaires administered by research staff over 5 consecutive days for each year of the study. Family cohesion and daily family support exhibited a significant buffering effect for several outcomes. Posttraumatic stress significantly mediated the effect of witnessing community violence on subsequent aggression. The strength of these indirect effects depended on level of family cohesion. The findings provide evidence in support of interventions provided at both individual and family levels. Mental health providers working with this population should be aware of the intertwined nature of exposure to community violence, posttraumatic stress, and subsequent maladaptive outcomes.

  19. Modelling population-level consequences of chronic external gamma irradiation in aquatic invertebrates under laboratory conditions

    Energy Technology Data Exchange (ETDEWEB)

    Lance, Emilie [Laboratoire de modelisation pour l' expertise environnementale (LM2E) Institut de Radioprotection et de Surete Nucleaire (IRSN), PRP-ENV, SERIS, Cadarache (France); Alonzo, Frederic, E-mail: frederic.alonzo@irsn.fr [Laboratoire d' ecotoxicologie des radionucleides (LECO) Institut de Radioprotection et de Surete Nucleaire (IRSN), PRP-ENV, SERIS, Cadarache (France); Garcia-Sanchez, Laurent [Laboratoire de biogeochimie, biodisponibilite et transferts des radionucleides (L2BT) Institut de Radioprotection et de Surete Nucleaire (IRSN), PRP-ENV, SERIS, Cadarache (France); Beaugelin-Seiller, Karine; Garnier-Laplace, Jacqueline [Laboratoire de modelisation pour l' expertise environnementale (LM2E) Institut de Radioprotection et de Surete Nucleaire (IRSN), PRP-ENV, SERIS, Cadarache (France)

    2012-07-01

    We modelled population-level consequences of chronic external gamma irradiation in aquatic invertebrates under laboratory conditions. We used Leslie matrices to combine life-history characteristics (duration of life stages, survival and fecundity rates) and dose rate-response curves for hatching, survival and reproduction fitted on effect data from the FREDERICA database. Changes in net reproductive rate R{sub 0} (offspring per individual) and asymptotic population growth rate {lambda} (dimensionless) were calculated over a range of dose rates in two marine polychaetes (Neanthes arenaceodentata and Ophryotrocha diadema) and a freshwater gastropod (Physa heterostropha). Sensitivities in R{sub 0} and {lambda} to changes in life-history traits were analysed in each species. Results showed that fecundity has the strongest influence on R{sub 0}. A delay in age at first reproduction is most critical for {lambda} independent of the species. Fast growing species were proportionally more sensitive to changes in individual endpoints than slow growing species. Reduction of 10% in population {lambda} were predicted at dose rates of 6918, 5012 and 74,131 {mu}Gy{center_dot}h{sup -1} in N. arenaceodentata, O. diadema and P. heterostropha respectively, resulting from a combination of strong effects on several individual endpoints in each species. These observations made 10%-reduction in {lambda} a poor criterion for population protection. The lowest significant changes in R{sub 0} and {lambda} were respectively predicted at a same dose rate of 1412 {mu}Gy h{sup -1} in N. arenaceodentata, at 760 and 716 {mu}Gy h{sup -1} in O. diadema and at 12,767 and 13,759 {mu}Gy h{sup -1} in P. heterostropha. These values resulted from a combination of slight but significant changes in several measured endpoints and were lower than effective dose rates calculated for the individual level in O. diadema and P. heterostropha. The relevance of the experimental dataset (external irradiation rather

  20. Dose-rate conversion factors for external exposure to photon and electron radiation from radionuclides occurring in routine releases from nuclear fuel cycle facilities

    International Nuclear Information System (INIS)

    Kocher, D.C.

    1980-01-01

    Dose-rate conversion factors for external exposure to photon and electron radiation are calculated for 240 radionuclides of potential importance in routine releases from nuclear fuel cycle facilities. Exposure modes considered are immersion in contaminated air, immersion in contaminated water, and irradiation from a contaminated ground surface. For each exposure mode, dose-rate conversion factors for photons and electrons are calculated for tissue-equivalent material at the body surface of an exposed individual. Dose-rate conversion factors for photons only are calculated for 22 body organs. (author)

  1. Proposal of a methodology to be applied for the characterization of external exposure risk of employees in nuclear medicine services

    International Nuclear Information System (INIS)

    Simoes, Rafael Figueiredo Pohlmann

    2010-01-01

    Nuclear medicine procedure requires the administration of radioactive material by injection, ingestion or inhalation. After incorporation, the patient becomes a mobile source of radiation and, after their examination; they can irradiate everyone on their way out of the Nuclear Medicine Service (NMS). A group of workers in this path is considered a critical group, but there are no conviction on this classification, because there are not measurements available. Thus, workers claiming for occupationally exposed individual's (OEI) rights are common. Employers are always in a complex situation, because if they decided to undertake the individual external monitoring of the critical working groups, the Court considers all as OEI and employers are taxed. On the other hand, if they do not provide monitoring, it is impossible to prove that these workers were not exposed to effective doses higher than individual annual public's limit and they lose the actions, too. This work proposes a methodology to evaluate, using TLD environmental monitors, air kerma rate at critical staff points in a NMS. This method provides relevant information about critical groups' exposure. From these results, the clinic or hospital may prove technically, without individual monitoring of employees, the classification of areas and can estimate the maximum flow of patients in the free areas which guarantees exposures below the public individual dose limit. This methodology has been applied successfully to a private clinic in Rio de Janeiro, which operates a NMS. The only critical group that received exposure statistically different from clinic background radiation was that on the antechamber of the NMS. This is a site that should be characterized as a supervised area and the group of workers in this environment as OEI, as the estimated extrapolated annual effective dose in this position was 1.2 +- 0.7 mSv/year, above the public annual limit (1,0 mSv/year). Normalizing by the number of patients, it can

  2. Biologically inspired information theory: Adaptation through construction of external reality models by living systems.

    Science.gov (United States)

    Nakajima, Toshiyuki

    2015-12-01

    Higher animals act in the world using their external reality models to cope with the uncertain environment. Organisms that have not developed such information-processing organs may also have external reality models built in the form of their biochemical, physiological, and behavioral structures, acquired by natural selection through successful models constructed internally. Organisms subject to illusions would fail to survive in the material universe. How can organisms, or living systems in general, determine the external reality from within? This paper starts with a phenomenological model, in which the self constitutes a reality model developed through the mental processing of phenomena. Then, the it-from-bit concept is formalized using a simple mathematical model. For this formalization, my previous work on an algorithmic process is employed to constitute symbols referring to the external reality, called the inverse causality, with additional improvements to the previous work. Finally, as an extension of this model, the cognizers system model is employed to describe the self as one of many material entities in a world, each of which acts as a subject by responding to the surrounding entities. This model is used to propose a conceptual framework of information theory that can deal with both the qualitative (semantic) and quantitative aspects of the information involved in biological processes. Copyright © 2015 Elsevier Ltd. All rights reserved.

  3. Using global magnetospheric models for simulation and interpretation of Swarm external field measurements

    DEFF Research Database (Denmark)

    Moretto, T.; Vennerstrøm, Susanne; Olsen, Nils

    2006-01-01

    simulated external contributions relevant for internal field modeling. These have proven very valuable for the design and planning of the up-coming multi-satellite Swarm mission. In addition, a real event simulation was carried out for a moderately active time interval when observations from the Orsted...... it consistently underestimates the dayside region 2 currents and overestimates the horizontal ionospheric closure currents in the dayside polar cap. Furthermore, with this example we illustrate the great benefit of utilizing the global model for the interpretation of Swarm external field observations and......, likewise, the potential of using Swarm measurements to test and improve the global model....

  4. A Model for Microcontroller Functionality Upset Induced by External Pulsed Electromagnetic Irradiation

    Science.gov (United States)

    2016-11-21

    AFRL-RD-PS- AFRL-RD-PS- TN-2016-0003 TN-2016-0003 A Model for Microcontroller Functionality Upset Induced by External Pulsed Electromagnetic...TYPE Technical Note 3. DATES COVERED (From - To) 22-11-2015 – 21-11-2016 4. TITLE AND SUBTITLE A Model for Microcontroller Functionality Upset Induced by... microcontroller (µC) subjected to external irradiation by a narrowband electromagnetic (EM) pulse. In our model, the state of a µC is completely specified by

  5. Modeling Natural Space Ionizing Radiation Effects on External Materials

    Science.gov (United States)

    Alstatt, Richard L.; Edwards, David L.; Parker, Nelson C. (Technical Monitor)

    2000-01-01

    Predicting the effective life of materials for space applications has become increasingly critical with the drive to reduce mission cost. Programs have considered many solutions to reduce launch costs including novel, low mass materials and thin thermal blankets to reduce spacecraft mass. Determining the long-term survivability of these materials before launch is critical for mission success. This presentation will describe an analysis performed on the outer layer of the passive thermal control blanket of the Hubble Space Telescope. This layer had degraded for unknown reasons during the mission, however ionizing radiation (IR) induced embrittlement was suspected. A methodology was developed which allowed direct comparison between the energy deposition of the natural environment and that of the laboratory generated environment. Commercial codes were used to predict the natural space IR environment model energy deposition in the material from both natural and laboratory IR sources, and design the most efficient test. Results were optimized for total and local energy deposition with an iterative spreadsheet. This method has been used successfully for several laboratory tests at the Marshall Space Flight Center. The study showed that the natural space IR environment, by itself, did not cause the premature degradation observed in the thermal blanket.

  6. Variation in calculated human exposure. Comparison of calculations with seven European human exposure models

    NARCIS (Netherlands)

    Swartjes F; ECO

    2003-01-01

    Twenty scenarios, differing with respect to land use, soil type and contaminant, formed the basis for calculating human exposure from soil contaminants with the use of models contributed by seven European countries (one model per country). Here, the human exposures to children and children

  7. Mitigating Errors in External Respiratory Surrogate-Based Models of Tumor Position

    International Nuclear Information System (INIS)

    Malinowski, Kathleen T.; McAvoy, Thomas J.; George, Rohini; Dieterich, Sonja; D'Souza, Warren D.

    2012-01-01

    Purpose: To investigate the effect of tumor site, measurement precision, tumor–surrogate correlation, training data selection, model design, and interpatient and interfraction variations on the accuracy of external marker-based models of tumor position. Methods and Materials: Cyberknife Synchrony system log files comprising synchronously acquired positions of external markers and the tumor from 167 treatment fractions were analyzed. The accuracy of Synchrony, ordinary-least-squares regression, and partial-least-squares regression models for predicting the tumor position from the external markers was evaluated. The quantity and timing of the data used to build the predictive model were varied. The effects of tumor–surrogate correlation and the precision in both the tumor and the external surrogate position measurements were explored by adding noise to the data. Results: The tumor position prediction errors increased during the duration of a fraction. Increasing the training data quantities did not always lead to more accurate models. Adding uncorrelated noise to the external marker-based inputs degraded the tumor–surrogate correlation models by 16% for partial-least-squares and 57% for ordinary-least-squares. External marker and tumor position measurement errors led to tumor position prediction changes 0.3–3.6 times the magnitude of the measurement errors, varying widely with model algorithm. The tumor position prediction errors were significantly associated with the patient index but not with the fraction index or tumor site. Partial-least-squares was as accurate as Synchrony and more accurate than ordinary-least-squares. Conclusions: The accuracy of surrogate-based inferential models of tumor position was affected by all the investigated factors, except for the tumor site and fraction index.

  8. Mitigating Errors in External Respiratory Surrogate-Based Models of Tumor Position

    Energy Technology Data Exchange (ETDEWEB)

    Malinowski, Kathleen T. [Department of Radiation Oncology, University of Maryland School of Medicine, Baltimore, MD (United States); Fischell Department of Bioengineering, University of Maryland, College Park, MD (United States); McAvoy, Thomas J. [Fischell Department of Bioengineering, University of Maryland, College Park, MD (United States); Department of Chemical and Biomolecular Engineering and Institute of Systems Research, University of Maryland, College Park, MD (United States); George, Rohini [Department of Radiation Oncology, University of Maryland School of Medicine, Baltimore, MD (United States); Dieterich, Sonja [Department of Radiation Oncology, Stanford University School of Medicine, Stanford, CA (United States); D' Souza, Warren D., E-mail: wdsou001@umaryland.edu [Department of Radiation Oncology, University of Maryland School of Medicine, Baltimore, MD (United States); Fischell Department of Bioengineering, University of Maryland, College Park, MD (United States)

    2012-04-01

    Purpose: To investigate the effect of tumor site, measurement precision, tumor-surrogate correlation, training data selection, model design, and interpatient and interfraction variations on the accuracy of external marker-based models of tumor position. Methods and Materials: Cyberknife Synchrony system log files comprising synchronously acquired positions of external markers and the tumor from 167 treatment fractions were analyzed. The accuracy of Synchrony, ordinary-least-squares regression, and partial-least-squares regression models for predicting the tumor position from the external markers was evaluated. The quantity and timing of the data used to build the predictive model were varied. The effects of tumor-surrogate correlation and the precision in both the tumor and the external surrogate position measurements were explored by adding noise to the data. Results: The tumor position prediction errors increased during the duration of a fraction. Increasing the training data quantities did not always lead to more accurate models. Adding uncorrelated noise to the external marker-based inputs degraded the tumor-surrogate correlation models by 16% for partial-least-squares and 57% for ordinary-least-squares. External marker and tumor position measurement errors led to tumor position prediction changes 0.3-3.6 times the magnitude of the measurement errors, varying widely with model algorithm. The tumor position prediction errors were significantly associated with the patient index but not with the fraction index or tumor site. Partial-least-squares was as accurate as Synchrony and more accurate than ordinary-least-squares. Conclusions: The accuracy of surrogate-based inferential models of tumor position was affected by all the investigated factors, except for the tumor site and fraction index.

  9. Advanced REACH tool: A Bayesian model for occupational exposure assessment

    NARCIS (Netherlands)

    McNally, K.; Warren, N.; Fransman, W.; Entink, R.K.; Schinkel, J.; Van Tongeren, M.; Cherrie, J.W.; Kromhout, H.; Schneider, T.; Tielemans, E.

    2014-01-01

    This paper describes a Bayesian model for the assessment of inhalation exposures in an occupational setting; the methodology underpins a freely available web-based application for exposure assessment, the Advanced REACH Tool (ART). The ART is a higher tier exposure tool that combines disparate

  10. Validation of the dermal exposure model in ECETOC TRA.

    Science.gov (United States)

    Marquart, Hans; Franken, Remy; Goede, Henk; Fransman, Wouter; Schinkel, Jody

    2017-08-01

    The ECETOC TRA model (presently version 3.1) is often used to estimate worker inhalation and dermal exposure in regulatory risk assessment. The dermal model in ECETOC TRA has not yet been validated by comparison with independent measured exposure levels. This was the goal of the present study. Measured exposure levels and relevant contextual information were gathered via literature search, websites of relevant occupational health institutes and direct requests for data to industry. Exposure data were clustered in so-called exposure cases, which are sets of data from one data source that are expected to have the same values for input parameters in the ECETOC TRA dermal exposure model. For each exposure case, the 75th percentile of measured values was calculated, because the model intends to estimate these values. The input values for the parameters in ECETOC TRA were assigned by an expert elicitation and consensus building process, based on descriptions of relevant contextual information.From more than 35 data sources, 106 useful exposure cases were derived, that were used for direct comparison with the model estimates. The exposure cases covered a large part of the ECETOC TRA dermal exposure model. The model explained 37% of the variance in the 75th percentiles of measured values. In around 80% of the exposure cases, the model estimate was higher than the 75th percentile of measured values. In the remaining exposure cases, the model estimate may not be sufficiently conservative.The model was shown to have a clear bias towards (severe) overestimation of dermal exposure at low measured exposure values, while all cases of apparent underestimation by the ECETOC TRA dermal exposure model occurred at high measured exposure values. This can be partly explained by a built-in bias in the effect of concentration of substance in product used, duration of exposure and the use of protective gloves in the model. The effect of protective gloves was calculated to be on average a

  11. Small--radiation-amplitude dynamical voltage model of an irradiated, externally unbiased Josephson tunnel junction

    International Nuclear Information System (INIS)

    McAdory, R.T. Jr.

    1988-01-01

    A theory is presented for the nonequilibrium voltage states of an irradiated Josephson junction shunted by an external resistor but with no external current or voltage biasing. This device, referred to as a free-running Josephson junction, is modeled in a small--radiation-amplitude, deterministic regime extending the previous work of Shenoy and Agarwal. The time-averaged induced voltage is treated as a dynamical variable, the external radiation is modeled as a current source, and the induced junction-radiation vector potential, with and without a mode structure, is treated to first order in the driving currents. A dynamical equation for the time-averaged induced voltage yields a (nonequilibrium) steady-state relation between the time-averaged induced voltage and the incident radiation amplitude valid for a wide range of voltages, including zero. Regions of bistability occur in the voltage--versus--incident-amplitude curves, some of which are dependent on the external resistor. The zero-voltage state breaks down, as the external radiation amplitude is increased, at a critical value of the incident-radiation amplitude inversely proportional to the external resistance

  12. Deflection modeling of permanent magnet spherical chains in the presence of external magnetic fields

    Energy Technology Data Exchange (ETDEWEB)

    O' Donoghue, Kilian, E-mail: kilianod@rennes.ucc.ie; Cantillon-Murphy, Pádraig, E-mail: padraig@alum.mit.edu

    2013-10-15

    This work examines the interaction of permanently magnetised spheres in the presence of external magnetic fields at the millimetre scale. Static chain formation and deflection models are described for N spheres in the presence of an external magnetic field. Analytical models are presented for the two sphere case by neglecting the effects of magnetocrystalline anisotropy while details of a numerical approach to solve a chain of N spheres are shown. The model is experimentally validated using chain deflections in 4.5 mm diameter spheres in groups of 2, 3 and 4 magnets in the presence of uniform magnetic fields, neglecting gravitational effects, with good agreement between the theoretical model and experimental results. This spherical chain structure could be used as an end effector for catheters as a deflection mechanism for magnetic guidance. The spherical point contacts result in large deflections for navigation around tight corners in endoluminal minimally invasive clinical applications. - Highlights: • We model the interaction of magnetic spheres with uniform external fields. • Analytical models are presented for two spheres interacting with an external field. • Numerical methods are used to model the interaction of N spheres in chain formations. • These models are tested experimentally. • We report good agreement between experiment and theory.

  13. Deflection modeling of permanent magnet spherical chains in the presence of external magnetic fields

    International Nuclear Information System (INIS)

    O'Donoghue, Kilian; Cantillon-Murphy, Pádraig

    2013-01-01

    This work examines the interaction of permanently magnetised spheres in the presence of external magnetic fields at the millimetre scale. Static chain formation and deflection models are described for N spheres in the presence of an external magnetic field. Analytical models are presented for the two sphere case by neglecting the effects of magnetocrystalline anisotropy while details of a numerical approach to solve a chain of N spheres are shown. The model is experimentally validated using chain deflections in 4.5 mm diameter spheres in groups of 2, 3 and 4 magnets in the presence of uniform magnetic fields, neglecting gravitational effects, with good agreement between the theoretical model and experimental results. This spherical chain structure could be used as an end effector for catheters as a deflection mechanism for magnetic guidance. The spherical point contacts result in large deflections for navigation around tight corners in endoluminal minimally invasive clinical applications. - Highlights: • We model the interaction of magnetic spheres with uniform external fields. • Analytical models are presented for two spheres interacting with an external field. • Numerical methods are used to model the interaction of N spheres in chain formations. • These models are tested experimentally. • We report good agreement between experiment and theory

  14. Using an external surrogate for predictor model training in real-time motion management of lung tumors

    Energy Technology Data Exchange (ETDEWEB)

    Rottmann, Joerg; Berbeco, Ross [Brigham and Women’s Hospital, Dana-Farber Cancer Institute and Harvard Medical School, Boston, Massachusetts 02115 (United States)

    2014-12-15

    Purpose: Precise prediction of respiratory motion is a prerequisite for real-time motion compensation techniques such as beam, dynamic couch, or dynamic multileaf collimator tracking. Collection of tumor motion data to train the prediction model is required for most algorithms. To avoid exposure of patients to additional dose from imaging during this procedure, the feasibility of training a linear respiratory motion prediction model with an external surrogate signal is investigated and its performance benchmarked against training the model with tumor positions directly. Methods: The authors implement a lung tumor motion prediction algorithm based on linear ridge regression that is suitable to overcome system latencies up to about 300 ms. Its performance is investigated on a data set of 91 patient breathing trajectories recorded from fiducial marker tracking during radiotherapy delivery to the lung of ten patients. The expected 3D geometric error is quantified as a function of predictor lookahead time, signal sampling frequency and history vector length. Additionally, adaptive model retraining is evaluated, i.e., repeatedly updating the prediction model after initial training. Training length for this is gradually increased with incoming (internal) data availability. To assess practical feasibility model calculation times as well as various minimum data lengths for retraining are evaluated. Relative performance of model training with external surrogate motion data versus tumor motion data is evaluated. However, an internal–external motion correlation model is not utilized, i.e., prediction is solely driven by internal motion in both cases. Results: Similar prediction performance was achieved for training the model with external surrogate data versus internal (tumor motion) data. Adaptive model retraining can substantially boost performance in the case of external surrogate training while it has little impact for training with internal motion data. A minimum

  15. Measurement and modeling of external radiation during 1985 from LAMPF [Los Alamos Meson Physics Facility] emissions

    International Nuclear Information System (INIS)

    Bowen, B.M.; Olsen, W.A.; Chen, Ili; Van Etten, D.M.

    1987-11-01

    An array of three portable, pressurized ionization chambers (PICs) continued to measure external radiation levels during 1985 caused by radionuclides emitted from the Los Alamos Meson Physics Facility (LAMPF). A Gaussian-type atmospheric dispersion model, using onsite meteorological and stack release data, was tested during this study. A more complex finite model, which takes into account the contribution of radiation at a receptor from different locations of the passing plume, was also tested. Monitoring results indicate that, as in 1984, a persistent wind up the Rio Grande Valley during the evening and early morning hours is largely responsible for causing the highest external radiation levels to occur to the northeast and north-northeast of LAMPF. However, because of increased turbulent mixing during the day, external radiation levels are generally much less during the day than at night. External radiation levels during 1985 show approximately a 75% reduction over 1984 levels. This resulted from a similar percentage reduction in LAMPF emissions caused by newly implemented emission controls. Comparison of predicted and measured daily external radiation levels indicates a high degree of correlation. The model also gives accurate estimates of measured concentrations over longer time periods. Comparison of predicted and measured hourly values indicates that the model generally tends to overpredict during the day and underpredict at night. 9 refs., 14 figs., 13 tabs

  16. Air pollution exposure modeling of individuals

    Science.gov (United States)

    Air pollution epidemiology studies of ambient fine particulate matter (PM2.5) often use outdoor concentrations as exposure surrogates. These surrogates can induce exposure error since they do not account for (1) time spent indoors with ambient PM2.5 levels attenuated from outdoor...

  17. Reconstruction of the external dose of evacuees from the contaminated areas based on simulation modelling

    International Nuclear Information System (INIS)

    Meckbach, R.; Chumak, V.V.

    1996-01-01

    Model calculations are being performed for the reconstruction of individual external gamma doses of population evacuated during the Chernobyl accident from the city of Pripyat and other settlements of the 30-km zone. The models are based on sets of dose rate measurements performed during the accident, on individual behavior histories of more than 30000 evacuees obtained by questionnaire survey and on location factors determined for characteristic housing buildings. Location factors were calculated by Monte Carlo simulations of photon transport for a typical housing block and village houses. Stochastic models for individual external dose reconstruction are described. Using Monte Carlo methods, frequency distributions representing the uncertainty of doses are calculated from an assessment of the uncertainty of the data. The determination of dose rate distributions in Pripyat is discussed. Exemplary results for individual external doses are presented

  18. A Study on Ganui-Dae’s External Form and Its Modeling for Restoration

    Directory of Open Access Journals (Sweden)

    Min-Soo Lee

    2013-12-01

    Full Text Available Ganui-Dae, built in the reign of King Sejong, Joseon Dynasty, is a comprehensive observatory. It has various instruments for observation and time signal such as Ganui, Gyupyo(Gnomon, water-hammering type Honui and Honsang, and so on. Studying on Ganui-Dae has been focused on its location, history, criterion, etc, so far. However, studying on its external form and construction method has been conducted insufficiently. This study suggests the model for restoration of Ganui-Dae. The model is based on the analysis about external form of Ganui-Dae in various antique maps, and its construction method in those days.

  19. Mechanistic modeling of the loss of protein sieving due to internal and external fouling of microfilters.

    Science.gov (United States)

    Bolton, Glen R; Apostolidis, Alex J

    2017-09-01

    Fed-batch and perfusion cell culture processes used to produce therapeutic proteins can use microfilters for product harvest. In this study, new explicit mathematical models of sieving loss due to internal membrane fouling, external membrane fouling, or a combination of the two were generated. The models accounted for membrane and cake structures and hindered solute transport. Internal membrane fouling was assumed to occur due to the accumulation of foulant on either membrane pore walls (pore-retention model) or membrane fibers (fiber-retention model). External cake fouling was assumed to occur either by the growth of a single incompressible cake layer (cake-growth) or by the accumulation of a number of independent cake layers (cake-series). The pore-retention model was combined with either the cake-series or cake-growth models to obtain models that describe internal and external fouling occurring either simultaneously or sequentially. The models were tested using well-documented sieving decline data available in the literature. The sequential pore-retention followed by cake-growth model provided a good fit of sieving decline data during beer microfiltration. The cake-series and cake-growth models provided good fits of sieving decline data during the microfiltration of a perfusion cell culture. The new models provide insights into the mechanisms of fouling that result in the loss of product sieving. © 2017 American Institute of Chemical Engineers Biotechnol. Prog., 33:1323-1333, 2017. © 2017 American Institute of Chemical Engineers.

  20. Development of a spatial stochastic multimedia exposure model to assess population exposure at a regional scale

    International Nuclear Information System (INIS)

    Caudeville, Julien; Bonnard, Roseline; Boudet, Céline; Denys, Sébastien; Govaert, Gérard; Cicolella, André

    2012-01-01

    Analyzing the relationship between the environment and health has become a major focus of public health efforts in France, as evidenced by the national action plans for health and the environment. These plans have identified the following two priorities: -identify and manage geographic areas where hotspot exposures are a potential risk to human health; and -reduce exposure inequalities. The aim of this study is to develop a spatial stochastic multimedia exposure model for detecting vulnerable populations and analyzing exposure determinants at a fine resolution and regional scale. A multimedia exposure model was developed by INERIS to assess the transfer of substances from the environment to humans through inhalation and ingestion pathways. The RESPIR project adds a spatial dimension by linking GIS (Geographic Information System) to the model. Tools are developed using modeling, spatial analysis and geostatistic methods to build and discretize interesting variables and indicators from different supports and resolutions on a 1-km 2 regular grid. We applied this model to the risk assessment of exposure to metals (cadmium, lead and nickel) using data from a region in France (Nord-Pas-de-Calais). The considered exposure pathways include the atmospheric contaminant inhalation and ingestion of soil, vegetation, meat, egg, milk, fish and drinking water. Exposure scenarios are defined for different reference groups (age, dietary properties, and the fraction of food produced locally). The two largest risks correspond to an ancient industrial site (Metaleurop) and the Lille agglomeration. In these areas, cadmium, vegetation ingestion and soil contamination are the principal determinants of the computed risk. -- Highlights: ► We present a multimedia exposure model for mapping environmental disparities. ► We perform a risk assessment on a region of France at a fine scale for three metals. ► We examine exposure determinants and detect vulnerable population. ► The largest

  1. Quantifying the spatial and temporal variation in dose from external exposure to radiation: a new tool for use on free-ranging wildlife

    International Nuclear Information System (INIS)

    Hinton, Thomas G.; Byrne, Michael E.; Webster, Sarah; Beasley, James C.

    2015-01-01

    Inadequate dosimetry is often the fundamental problem in much of the controversial research dealing with radiation effects on free-ranging wildlife. Such research is difficult because of the need to measure dose from several potential pathways of exposure (i.e., internal contamination, external irradiation, and inhalation). Difficulties in quantifying external exposures can contribute significantly to the uncertainties of dose-effect relationships. Quantifying an animal's external exposure due to spatial–temporal use of habitats that can vary by orders of magnitude in radiation levels is particularly challenging. Historically, wildlife dosimetry studies have largely ignored or been unable to accurately quantify variability in external dose because of technological limitations. The difficulties of quantifying the temporal–spatial aspects of external irradiation prompted us to develop a new dosimetry instrument for field research. We merged two existing technologies [Global Positioning Systems (GPS) and electronic dosimeters] to accommodate the restrictive conditions of having a combined unit small enough to be unobtrusively worn on the neck of a free-ranging animal, and sufficiently robust to withstand harsh environmental conditions. The GPS–dosimeter quantifies the spatial and temporal variation in external dose as wildlife traverse radioactively contaminated habitats and sends, via satellites, an animal's location and short term integrated dose to the researcher at a user-defined interval. Herein we describe: (1) the GPS–dosimeters; (2) tests to compare their uniformity of response to external irradiation under laboratory conditions; (3) field tests of their durability when worn on wildlife under natural conditions; and (4) a field application of the new technology at a radioactively contaminated site. Use of coupled GPS–dosimetry will allow, for the first time, researchers to better understand the relationship of animals to their contaminated

  2. Retrospective dose assessment for the population living in areas of local fallout from the Semipalatinsk nuclear test site. Part 1: external exposure

    International Nuclear Information System (INIS)

    Gordeev, Konstantin; Shinkarev, Sergey; Ilyin, Leonid; Bouville, Andre; Luckyanov, Nickolas; Simon, Steven L.; Hoshi, Masaharu

    2006-01-01

    A short analysis of all 111 atmospheric events conducted at the Semipalatinsk Test Site (STS) in 1949-1962 with regard to significant off-site exposure (more than 5 mSv of the effective dose during the first year after the explosion) has been made. The analytical method used to assess external exposure to the residents living in settlements near the STS is described. This method makes used of the archival data on the radiological conditions, including the measurements of exposure rate. Special attention was given to the residents of Dolon and Kanonerka villages exposed mainly as a result of the first test, detonated on August 29, 1949. For the residents of those settlements born in 1935, the dose estimates calculated according to the analytical method, are compared to those derived from the thermoluminescence measurements in bricks and electron paramagnetic resonance measurements in teeth. The methods described in this paper were used for external dose assessment for the cohort members at an initial stage of an ongoing epidemiological study conducted by the U.S. National Cancer Institute in the Republic of Kazakhstan. Recently revised methods and estimates of external exposure for that cohort are given in another paper (Simon et al.) in this conference. (author)

  3. Impact of external sources of infection on the dynamics of bovine tuberculosis in modelled badger populations

    Directory of Open Access Journals (Sweden)

    Hardstaff Joanne L

    2012-06-01

    Full Text Available Abstract Background The persistence of bovine TB (bTB in various countries throughout the world is enhanced by the existence of wildlife hosts for the infection. In Britain and Ireland, the principal wildlife host for bTB is the badger (Meles meles. The objective of our study was to examine the dynamics of bTB in badgers in relation to both badger-derived infection from within the population and externally-derived, trickle-type, infection, such as could occur from other species or environmental sources, using a spatial stochastic simulation model. Results The presence of external sources of infection can increase mean prevalence and reduce the threshold group size for disease persistence. Above the threshold equilibrium group size of 6–8 individuals predicted by the model for bTB persistence in badgers based on internal infection alone, external sources of infection have relatively little impact on the persistence or level of disease. However, within a critical range of group sizes just below this threshold level, external infection becomes much more important in determining disease dynamics. Within this critical range, external infection increases the ratio of intra- to inter-group infections due to the greater probability of external infections entering fully-susceptible groups. The effect is to enable bTB persistence and increase bTB prevalence in badger populations which would not be able to maintain bTB based on internal infection alone. Conclusions External sources of bTB infection can contribute to the persistence of bTB in badger populations. In high-density badger populations, internal badger-derived infections occur at a sufficient rate that the additional effect of external sources in exacerbating disease is minimal. However, in lower-density populations, external sources of infection are much more important in enhancing bTB prevalence and persistence. In such circumstances, it is particularly important that control strategies to

  4. Impact of external sources of infection on the dynamics of bovine tuberculosis in modelled badger populations.

    Science.gov (United States)

    Hardstaff, Joanne L; Bulling, Mark T; Marion, Glenn; Hutchings, Michael R; White, Piran C L

    2012-06-27

    The persistence of bovine TB (bTB) in various countries throughout the world is enhanced by the existence of wildlife hosts for the infection. In Britain and Ireland, the principal wildlife host for bTB is the badger (Meles meles). The objective of our study was to examine the dynamics of bTB in badgers in relation to both badger-derived infection from within the population and externally-derived, trickle-type, infection, such as could occur from other species or environmental sources, using a spatial stochastic simulation model. The presence of external sources of infection can increase mean prevalence and reduce the threshold group size for disease persistence. Above the threshold equilibrium group size of 6-8 individuals predicted by the model for bTB persistence in badgers based on internal infection alone, external sources of infection have relatively little impact on the persistence or level of disease. However, within a critical range of group sizes just below this threshold level, external infection becomes much more important in determining disease dynamics. Within this critical range, external infection increases the ratio of intra- to inter-group infections due to the greater probability of external infections entering fully-susceptible groups. The effect is to enable bTB persistence and increase bTB prevalence in badger populations which would not be able to maintain bTB based on internal infection alone. External sources of bTB infection can contribute to the persistence of bTB in badger populations. In high-density badger populations, internal badger-derived infections occur at a sufficient rate that the additional effect of external sources in exacerbating disease is minimal. However, in lower-density populations, external sources of infection are much more important in enhancing bTB prevalence and persistence. In such circumstances, it is particularly important that control strategies to reduce bTB in badgers include efforts to minimise such

  5. External Validation of Prediction Models for Pneumonia in Primary Care Patients with Lower Respiratory Tract Infection

    DEFF Research Database (Denmark)

    Schierenberg, Alwin; Minnaard, Margaretha C; Hopstaken, Rogier M

    2016-01-01

    BACKGROUND: Pneumonia remains difficult to diagnose in primary care. Prediction models based on signs and symptoms (S&S) serve to minimize the diagnostic uncertainty. External validation of these models is essential before implementation into routine practice. In this study all published S&S mode...... discriminative accuracy coupled with reasonable to good calibration across the IPD of different study populations. This model is therefore the main candidate for primary care use....

  6. Implementation of PSA models to estimate the probabilities associated with external event combination

    International Nuclear Information System (INIS)

    Burgazzi, Luciano

    2014-01-01

    This note endeavors to address some significant issues revealed by the Fukushima accident in Japan in 2011, such as the analysis of various dependency aspects arisen in the light of the external event PSA framework, as the treatment of the correlated hazards. To this aim some foundational notions to implement the PSA models related to specific aspects, like the external hazard combination, e.g., earthquake and tsunami as at the Fukushima accident, and the external hazard-caused internal events, e.g., seismic induced fire, are proposed and discussed to be incorporated within the risk assessment structure. Risk assessment of external hazards is required and utilized as an integrated part of PRA for operating and new reactor units. In the light of the Fukushima accident, of special interest are correlated events, whose modelling is proposed in the present study, in the form of some theoretical concepts, which lay the foundations for the PSA framework implementation. An applicative example is presented for illustrative purposes, since the analysis is carried out on the basis of generic numerical values assigned to an oversimplified model and results are achieved without any baseline comparison. Obviously the first step aimed at the process endorsement is the analysis of all available information in order to determine the level of applicability of the observed specific plant site events to the envisaged model and the statistical correlation analysis for event occurrence data that can be used as part of this process. Despite these drawbacks that actually do not qualify the achieved results, the present work represents an exploratory study aimed at resolving current open issues to be resolved in the PSA, like topics related to unanticipated scenarios: the combined external hazards of the earthquake and tsunami in Fukushima, external hazards causing internal events, such as seismic induced fire. These topics are to be resolved among the other ones as emerging from the

  7. Femoral Component External Rotation Affects Knee Biomechanics: A Computational Model of Posterior-stabilized TKA.

    Science.gov (United States)

    Kia, Mohammad; Wright, Timothy M; Cross, Michael B; Mayman, David J; Pearle, Andrew D; Sculco, Peter K; Westrich, Geoffrey H; Imhauser, Carl W

    2018-01-01

    The correct amount of external rotation of the femoral component during TKA is controversial because the resulting changes in biomechanical knee function associated with varying degrees of femoral component rotation are not well understood. We addressed this question using a computational model, which allowed us to isolate the biomechanical impact of geometric factors including bony shapes, location of ligament insertions, and implant size across three different knees after posterior-stabilized (PS) TKA. Using a computational model of the tibiofemoral joint, we asked: (1) Does external rotation unload the medial collateral ligament (MCL) and what is the effect on lateral collateral ligament tension? (2) How does external rotation alter tibiofemoral contact loads and kinematics? (3) Does 3° external rotation relative to the posterior condylar axis align the component to the surgical transepicondylar axis (sTEA) and what anatomic factors of the femoral condyle explain variations in maximum MCL tension among knees? We incorporated a PS TKA into a previously developed computational knee model applied to three neutrally aligned, nonarthritic, male cadaveric knees. The computational knee model was previously shown to corroborate coupled motions and ligament loading patterns of the native knee through a range of flexion. Implant geometries were virtually installed using hip-to-ankle CT scans through measured resection and anterior referencing surgical techniques. Collateral ligament properties were standardized across each knee model by defining stiffness and slack lengths based on the healthy population. The femoral component was externally rotated from 0° to 9° relative to the posterior condylar axis in 3° increments. At each increment, the knee was flexed under 500 N compression from 0° to 90° simulating an intraoperative examination. The computational model predicted collateral ligament forces, compartmental contact forces, and tibiofemoral internal/external and

  8. Data Sources Available for Modeling Environmental Exposures in Older Adults

    Science.gov (United States)

    This report, “Data Sources Available for Modeling Environmental Exposures in Older Adults,” focuses on information sources and data available for modeling environmental exposures in the older U.S. population, defined here to be people 60 years and older, with an emphasis on those...

  9. External validation of multivariable prediction models: a systematic review of methodological conduct and reporting

    Science.gov (United States)

    2014-01-01

    Background Before considering whether to use a multivariable (diagnostic or prognostic) prediction model, it is essential that its performance be evaluated in data that were not used to develop the model (referred to as external validation). We critically appraised the methodological conduct and reporting of external validation studies of multivariable prediction models. Methods We conducted a systematic review of articles describing some form of external validation of one or more multivariable prediction models indexed in PubMed core clinical journals published in 2010. Study data were extracted in duplicate on design, sample size, handling of missing data, reference to the original study developing the prediction models and predictive performance measures. Results 11,826 articles were identified and 78 were included for full review, which described the evaluation of 120 prediction models. in participant data that were not used to develop the model. Thirty-three articles described both the development of a prediction model and an evaluation of its performance on a separate dataset, and 45 articles described only the evaluation of an existing published prediction model on another dataset. Fifty-seven percent of the prediction models were presented and evaluated as simplified scoring systems. Sixteen percent of articles failed to report the number of outcome events in the validation datasets. Fifty-four percent of studies made no explicit mention of missing data. Sixty-seven percent did not report evaluating model calibration whilst most studies evaluated model discrimination. It was often unclear whether the reported performance measures were for the full regression model or for the simplified models. Conclusions The vast majority of studies describing some form of external validation of a multivariable prediction model were poorly reported with key details frequently not presented. The validation studies were characterised by poor design, inappropriate handling

  10. A statistical framework for the validation of a population exposure model based on personal exposure data

    Science.gov (United States)

    Rodriguez, Delphy; Valari, Myrto; Markakis, Konstantinos; Payan, Sébastien

    2016-04-01

    Currently, ambient pollutant concentrations at monitoring sites are routinely measured by local networks, such as AIRPARIF in Paris, France. Pollutant concentration fields are also simulated with regional-scale chemistry transport models such as CHIMERE (http://www.lmd.polytechnique.fr/chimere) under air-quality forecasting platforms (e.g. Prev'Air http://www.prevair.org) or research projects. These data may be combined with more or less sophisticated techniques to provide a fairly good representation of pollutant concentration spatial gradients over urban areas. Here we focus on human exposure to atmospheric contaminants. Based on census data on population dynamics and demographics, modeled outdoor concentrations and infiltration of outdoor air-pollution indoors we have developed a population exposure model for ozone and PM2.5. A critical challenge in the field of population exposure modeling is model validation since personal exposure data are expensive and therefore, rare. However, recent research has made low cost mobile sensors fairly common and therefore personal exposure data should become more and more accessible. In view of planned cohort field-campaigns where such data will be available over the Paris region, we propose in the present study a statistical framework that makes the comparison between modeled and measured exposures meaningful. Our ultimate goal is to evaluate the exposure model by comparing modeled exposures to monitor data. The scientific question we address here is how to downscale modeled data that are estimated on the county population scale at the individual scale which is appropriate to the available measurements. To assess this question we developed a Bayesian hierarchical framework that assimilates actual individual data into population statistics and updates the probability estimate.

  11. Radiation exposure modeling and project schedule visualization

    International Nuclear Information System (INIS)

    Jaquish, W.R.; Enderlin, V.R.

    1995-10-01

    This paper discusses two applications using IGRIP (Interactive Graphical Robot Instruction Program) to assist environmental remediation efforts at the Department of Energy (DOE) Hanford Site. In the first application, IGRIP is used to calculate the estimated radiation exposure to workers conducting tasks in radiation environments. In the second, IGRIP is used as a configuration management tool to detect interferences between equipment and personnel work areas for multiple projects occurring simultaneously in one area. Both of these applications have the capability to reduce environmental remediation costs by reducing personnel radiation exposure and by providing a method to effectively manage multiple projects in a single facility

  12. Nuclear energy - Radioprotection - Procedure for radiation protection monitoring in nuclear installations for external exposure to weakly penetrating radiation, especially to beta radiation

    International Nuclear Information System (INIS)

    2002-01-01

    This International Standard specifies a procedure for radiation protection monitoring in nuclear installations for external exposure to weakly penetrating radiation, especially to beta radiation and describes the procedure in radiation protection monitoring for external exposure to weakly penetrating radiation in nuclear installations. This radiation comprises β - radiation, β + radiation and conversion electron radiation as well as photon radiation with energies below 15 keV. This International Standard describes the procedure in radiation protection planning and monitoring as well as the measurement and analysis to be applied. It applies to regular nuclear power plant operation including maintenance, waste handling and decommissioning. The recommendations of this International Standard may also be transferred to other nuclear fields including reprocessing, if the area-specific issues are considered. This International Standard may also be applied to radiation protection at accelerator facilities and in nuclear medicine, biology and research facilities

  13. A dermatotoxicokinetic model of human exposures to jet fuel.

    Science.gov (United States)

    Kim, David; Andersen, Melvin E; Nylander-French, Leena A

    2006-09-01

    Workers, both in the military and the commercial airline industry, are exposed to jet fuel by inhalation and dermal contact. We present a dermatotoxicokinetic (DTK) model that quantifies the absorption, distribution, and elimination of aromatic and aliphatic components of jet fuel following dermal exposures in humans. Kinetic data were obtained from 10 healthy volunteers following a single dose of JP-8 to the forearm over a surface area of 20 cm2. Blood samples were taken before exposure (t = 0 h), after exposure (t = 0.5 h), and every 0.5 h for up to 3.5 h postexposure. The DTK model that best fit the data included five compartments: (1) surface, (2) stratum corneum (SC), (3) viable epidermis, (4) blood, and (5) storage. The DTK model was used to predict blood concentrations of the components of JP-8 based on dermal-exposure measurements made in occupational-exposure settings in order to better understand the toxicokinetic behavior of these compounds. Monte Carlo simulations of dermal exposure and cumulative internal dose demonstrated no overlap among the low-, medium-, and high-exposure groups. The DTK model provides a quantitative understanding of the relationship between the mass of JP-8 components in the SC and the concentrations of each component in the systemic circulation. The model may be used for the development of a toxicokinetic modeling strategy for multiroute exposure to jet fuel.

  14. Internal and external North Atlantic Sector variability in the Kiel climate model

    Energy Technology Data Exchange (ETDEWEB)

    Latif, Mojib; Park, Wonsun; Ding, Hui; Keenlyside, Noel S. [Leibniz-Inst. fuer Meereswissenschaften, Kiel (Germany)

    2009-08-15

    The internal and external North Atlantic Sector variability is investigated by means of a multimillennial control run and forced experiments with the Kiel Climate Model (KCM). The internal variability is studied by analyzing the control run. The externally forced variability is investigated in a run with periodic millennial solar forcing and in greenhouse warming experiments with enhanced carbon dioxide concentrations. The surface air temperature (SAT) averaged over the Northern Hemisphere simulated in the control run displays enhanced variability relative to the red background at decadal, centennial, and millennial timescales. Special emphasis is given to the variability of the Meridional Overturning Circulation (MOC). The MOC plays an important role in the generation of internal climate modes. Furthermore, the MOC provides a strong negative feedback on the Northern Hemisphere SAT in both the solar and greenhouse warming experiments, thereby moderating the direct effects of the external forcing in the North Atlantic. The implications of the results for decadal predictability are discussed. (orig.)

  15. How do dynamic capabilities transform external technologies into firms’ renewed technological resources? – A mediation model

    DEFF Research Database (Denmark)

    Li-Ying, Jason; Wang, Yuandi; Ning, Lutao

    2016-01-01

    microfoundations of dynamic technological capabilities, mediate the relationship between external technology breadth and firms’ technological innovation performance, based on the resource-based view and dynamic capability view. Using a sample of listed Chinese licensee firms, we find that firms must broadly......How externally acquired resources may become valuable, rare, hard-to-imitate, and non-substitute resource bundles through the development of dynamic capabilities? This study proposes and tests a mediation model of how firms’ internal technological diversification and R&D, as two distinctive...... explore external technologies to ignite the dynamism in internal technological diversity and in-house R&D, which play their crucial roles differently to transform and reconfigure firms’ technological resources....

  16. External costs in the global energy optimization models. A tool in favour of sustain ability

    International Nuclear Information System (INIS)

    Cabal Cuesta, H.

    2007-01-01

    The aim of this work is the analysis of the effects of the GHG external costs internalization in the energy systems. This may provide a useful tool to support decision makers to help reaching the energy systems sustain ability. External costs internalization has been carried out using two methods. First, CO 2 externalities of different power generation technologies have been internalized to evaluate their effects on the economic competitiveness of these present and future technologies. The other method consisted of analysing and optimizing the global energy system, from an economic and environmental point of view, using the global energy optimization model generator, TIMES, with a time horizon of 50 years. Finally, some scenarios regarding environmental and economic strategic measures have been analysed. (Author)

  17. Modeling attitude towards drug treament: the role of internal motivation, external pressure, and dramatic relief.

    Science.gov (United States)

    Conner, Bradley T; Longshore, Douglas; Anglin, M Douglas

    2009-04-01

    Motivation for change has historically been viewed as the crucial element affecting responsiveness to drug treatment. Various external pressures, such as legal coercion, may engender motivation in an individual previously resistant to change. Dramatic relief may be the change process that is most salient as individuals internalize such external pressures. Results of structural equation modeling on data from 465 drug users (58.9% male; 21.3% Black, 34.2% Hispanic/Latino, and 35.1% White) entering drug treatment indicated that internal motivation and external pressure significantly and positively predicted dramatic relief and that dramatic relief significantly predicted attitudes towards drug treatment: chi (2) = 142.20, df = 100, p relief is also likely to be high. When dramatic relief is high, attitudes towards drug treatment are likely to be positive. The findings indicate that interventions to get individuals into drug treatment should include processes that promote Dramatic Relief. Implications for addictions health services are discussed.

  18. Influence of periodic external fields in multiagent models with language dynamics

    Science.gov (United States)

    Palombi, Filippo; Ferriani, Stefano; Toti, Simona

    2017-12-01

    We investigate large-scale effects induced by external fields, phenomenologically interpreted as mass media, in multiagent models evolving with the microscopic dynamics of the binary naming game. In particular, we show that a single external field, broadcasting information at regular time intervals, can reverse the majority opinion of the population, provided the frequency and the effectiveness of the sent messages lie above well-defined thresholds. We study the phase structure of the model in the mean field approximation and in numerical simulations with several network topologies. We also investigate the influence on the agent dynamics of two competing external fields, periodically broadcasting different messages. In finite regions of the parameter space we observe periodic equilibrium states in which the average opinion densities are reversed with respect to naive expectations. Such equilibria occur in two cases: (i) when the frequencies of the competing messages are different but close to each other; (ii) when the frequencies are equal and the relative time shift of the messages does not exceed half a period. We interpret the observed phenomena as a result of the interplay between the external fields and the internal dynamics of the agents and conclude that, depending on the model parameters, the naming game is consistent with scenarios of first- or second-mover advantage (to borrow an expression from the jargon of business strategy).

  19. Phase structure of Gross-Neveu model with compactification in the presence of external magnetic field

    International Nuclear Information System (INIS)

    Zhokhov, R.N.; Kolmakov, P. B.; Zhukovsky, V.Ch.; Klimenko, K.G.

    2016-01-01

    In the paper there have been studied Gross-Neveu model in (2+1)-dimensional space-time with one compactified dimension in presence of external magnetic field at finite temperature. Magnetic field is directed along the uncompactified dimension that is along the axis of the cylinder on which the system lives. Chiral symmetry breaking and corresponding phase structure of the model is investigated in the leading order of (1/N) expansion

  20. Internal Motion Estimation by Internal-external Motion Modeling for Lung Cancer Radiotherapy.

    Science.gov (United States)

    Chen, Haibin; Zhong, Zichun; Yang, Yiwei; Chen, Jiawei; Zhou, Linghong; Zhen, Xin; Gu, Xuejun

    2018-02-27

    The aim of this study is to develop an internal-external correlation model for internal motion estimation for lung cancer radiotherapy. Deformation vector fields that characterize the internal-external motion are obtained by respectively registering the internal organ meshes and external surface meshes from the 4DCT images via a recently developed local topology preserved non-rigid point matching algorithm. A composite matrix is constructed by combing the estimated internal phasic DVFs with external phasic and directional DVFs. Principle component analysis is then applied to the composite matrix to extract principal motion characteristics, and generate model parameters to correlate the internal-external motion. The proposed model is evaluated on a 4D NURBS-based cardiac-torso (NCAT) synthetic phantom and 4DCT images from five lung cancer patients. For tumor tracking, the center of mass errors of the tracked tumor are 0.8(±0.5)mm/0.8(±0.4)mm for synthetic data, and 1.3(±1.0)mm/1.2(±1.2)mm for patient data in the intra-fraction/inter-fraction tracking, respectively. For lung tracking, the percent errors of the tracked contours are 0.06(±0.02)/0.07(±0.03) for synthetic data, and 0.06(±0.02)/0.06(±0.02) for patient data in the intra-fraction/inter-fraction tracking, respectively. The extensive validations have demonstrated the effectiveness and reliability of the proposed model in motion tracking for both the tumor and the lung in lung cancer radiotherapy.

  1. A random utility model of delay discounting and its application to people with externalizing psychopathology.

    Science.gov (United States)

    Dai, Junyi; Gunn, Rachel L; Gerst, Kyle R; Busemeyer, Jerome R; Finn, Peter R

    2016-10-01

    Previous studies have demonstrated that working memory capacity plays a central role in delay discounting in people with externalizing psychopathology. These studies used a hyperbolic discounting model, and its single parameter-a measure of delay discounting-was estimated using the standard method of searching for indifference points between intertemporal options. However, there are several problems with this approach. First, the deterministic perspective on delay discounting underlying the indifference point method might be inappropriate. Second, the estimation procedure using the R2 measure often leads to poor model fit. Third, when parameters are estimated using indifference points only, much of the information collected in a delay discounting decision task is wasted. To overcome these problems, this article proposes a random utility model of delay discounting. The proposed model has 2 parameters, 1 for delay discounting and 1 for choice variability. It was fit to choice data obtained from a recently published data set using both maximum-likelihood and Bayesian parameter estimation. As in previous studies, the delay discounting parameter was significantly associated with both externalizing problems and working memory capacity. Furthermore, choice variability was also found to be significantly associated with both variables. This finding suggests that randomness in decisions may be a mechanism by which externalizing problems and low working memory capacity are associated with poor decision making. The random utility model thus has the advantage of disclosing the role of choice variability, which had been masked by the traditional deterministic model. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

  2. Parents' attachment histories and children's externalizing and internalizing behaviors: exploring family systems models of linkage.

    Science.gov (United States)

    Cowan, P A; Cowan, C P; Cohn, D A; Pearson, J L

    1996-02-01

    Twenty-seven mothers and 27 fathers were given the Adult Attachment Interview (M. Main & R. Goldwyn, in press) when their children were 3.5 years old. Continuous ratings of narrative coherence, probable experience quality (parents perceived as loving), and state of mind (current anger at parents) were entered as latent variables in partial least squares structural equation models that included observational measures of marital quality and parenting style. Models that include fathers' attachment histories predicted more variance in kindergarten teachers' descriptions of children's externalizing behavior, whereas models that include mothers' attachment histories predicted more variance in children's internalizing behavior. Marital data added predictive power to the equations. Discussion is focused on the importance of integrating attachment and family systems approaches, and of parents' gender and marital quality, in understanding specific links between parents' attachment histories and their young children's externalizing and internalizing behaviors.

  3. Personnel radiation protection. Situation of the dosimetry surveillance of external exposure in 2003; La radioprotection des travailleurs. Bilan de la surveillance dosimetrique de l'exposition externe en 2003

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2003-07-01

    The situation of external exposure of workers for the year 2003 has been realised according to the same method than this one of the year 2002. It does not show big variations of trends, both in term of workforce watched and collective doses alike associated in the different sectors of activity. Some differences observed between the two years can explain by real evolutions of situations. For example, the 2800 workers registered in the veterinary sector are the result of a better awareness of this profession for the radiation protection during the last months. Some variations can be the results of artefacts in the data processing. The centralization at I.R.S.N. of the whole of dosimetry data should allow to make easy the data treatment and to improve the statistics of occupational exposure. (N.C.)

  4. Animal Model Selection for Inhalational HCN Exposure

    Science.gov (United States)

    2016-08-01

    effects. Following acute inhalation exposure in humans and animals, cyanide is found in the lung, heart, blood , kidneys, and brain (Ballantyne, 1983...Pritchard, 2007). Other direct or secondary effects associated with CN are reacting with the ferric and carbonyl group of enzymes (e.g. catalase...mechanisms occurs before myocardial depression. Clinically, an initial period of bradycardia and hypertension may occur, followed by hypotension with reflex

  5. Exporters’ exposures to currencies: Beyond the loglinear model

    NARCIS (Netherlands)

    Boudt, K.M.R.; Liu, F.; Sercu, P.

    2016-01-01

    We extend the constant-elasticity regression that is the default choice when equities' exposure to currencies is estimated. In a proper real-option-style model for the exporters' equity exposure to the foreign exchange rate, we argue, the convexity of the relationship implies that the elasticity

  6. Population Pharmacokinetics of Intravenous Paracetamol (Acetaminophen) in Preterm and Term Neonates: Model Development and External Evaluation.

    Science.gov (United States)

    Cook, Sarah F; Roberts, Jessica K; Samiee-Zafarghandy, Samira; Stockmann, Chris; King, Amber D; Deutsch, Nina; Williams, Elaine F; Allegaert, Karel; Wilkins, Diana G; Sherwin, Catherine M T; van den Anker, John N

    2016-01-01

    The aims of this study were to develop a population pharmacokinetic model for intravenous paracetamol in preterm and term neonates and to assess the generalizability of the model by testing its predictive performance in an external dataset. Nonlinear mixed-effects models were constructed from paracetamol concentration-time data in NONMEM 7.2. Potential covariates included body weight, gestational age, postnatal age, postmenstrual age, sex, race, total bilirubin, and estimated glomerular filtration rate. An external dataset was used to test the predictive performance of the model through calculation of bias, precision, and normalized prediction distribution errors. The model-building dataset included 260 observations from 35 neonates with a mean gestational age of 33.6 weeks [standard deviation (SD) 6.6]. Data were well-described by a one-compartment model with first-order elimination. Weight predicted paracetamol clearance and volume of distribution, which were estimated as 0.348 L/h (5.5 % relative standard error; 30.8 % coefficient of variation) and 2.46 L (3.5 % relative standard error; 14.3 % coefficient of variation), respectively, at the mean subject weight of 2.30 kg. An external evaluation was performed on an independent dataset that included 436 observations from 60 neonates with a mean gestational age of 35.6 weeks (SD 4.3). The median prediction error was 10.1 % [95 % confidence interval (CI) 6.1-14.3] and the median absolute prediction error was 25.3 % (95 % CI 23.1-28.1). Weight predicted intravenous paracetamol pharmacokinetics in neonates ranging from extreme preterm to full-term gestational status. External evaluation suggested that these findings should be generalizable to other similar patient populations.

  7. Dose estimates from protracted external exposure of inhabitants living in contaminated area of Russia after the Chernobyl accident

    International Nuclear Information System (INIS)

    Yonehara, H.; Sahoo, S.K.; Kurotaki, K.; Uchiyama, M.; Ramzaev, V.P.; Barishkov, N.; Mishin, A.; Barkovski, A.

    2000-01-01

    With respect to the radiation risk assessment, it is important to estimate the accurate doses of inhabitants, due to protracted exposure after the Chernobyl accident as well as the high doses just after the accident. We used a model for estimation of the dose with a long-term temporal change using information of dose rate on the ground and profile of the activity depth distribution in soil. A value C t [μSv h -1 /(MBq m -2 )], which is dose rate in air corresponding to the initial deposition of 137 Cs on the ground just after the accident, was analyzed using the results of the measurements of dose rate in air and activity in soil samples in the contaminated area of Bryansk region in Russia. From the analysis, the value, C 12 at 12 years after the accident can be predicted by categorizing usage of the land. The values obtained from the results of the actual measurement were 1.5 for forest, 1.0 for pasture, 0.6 for yard, and 0.45 for arable or kitchen garden. Temporal change of C t was estimated with a vertical migration model of activity in soil developed by Golikov et al. Annual dose due to 137 Cs and 134 Cs contamination in the period from 1987 to 1999 in farmers, and forest workers were estimated by the model using above values. The results were in good agreement with those obtained by using the personal dose monitoring. The cumulative doses of the inhabitants estimated by the model range from 10 to 60 mSv. (author)

  8. Realistic modelling of external flooding scenarios - A multi-disciplinary approach

    International Nuclear Information System (INIS)

    Brinkman, J.L.

    2014-01-01

    Extreme phenomena, such as storm surges or high river water levels, may endanger the safety of nuclear power plants (NPPs) by inundation of the plant site with subsequent damage on safety-related buildings. Flooding may result in simultaneous failures of safety-related components, such as service water pumps and electrical equipment. In addition, the accessibility of the plant may be impeded due to flooding of the plant environment. These consequences are so severe that, (re)assessments of flood risk and flood protection measures should be based on accurate state-of-the-art methods. Dutch nuclear regulations require that a nuclear power plant shall withstand all external initiating events with a return period lower than one million years. For external flooding, this requirement is the basis of the so-called nuclear design level (nucleair ontwerp peil, NOP) of the buildings for external flooding, i.e. the water level at which a system - among others, the nuclear island and the ultimate heat sink - should still function properly. In determining the NOP, the mean water level, wave height and wave behaviour during storm surges are taken into account. This concept could also be used to implement external flooding in a PSA, by assuming that floods exceeding NOP levels directly lead to core damage. However, this straightforward modelling ignores some important aspects: the first is the mitigating effect of the external flood protection as dikes or dunes; the second aspect is that although water levels lower than NOP will not directly lead to core damage, they could do so indirectly as a result of combinations of system loss by flooding and random failure of required safety systems that have to bring the plant in a safe, stable state. Time is a third aspect: failure mechanisms need time to develop and time (via duration of the flood) determines the amount of water on site. This paper describes a PSA approach that takes the (structural) reliability of the external defences

  9. Development of a spatial stochastic multimedia exposure model to assess population exposure at a regional scale.

    Science.gov (United States)

    Caudeville, Julien; Bonnard, Roseline; Boudet, Céline; Denys, Sébastien; Govaert, Gérard; Cicolella, André

    2012-08-15

    Analyzing the relationship between the environment and health has become a major focus of public health efforts in France, as evidenced by the national action plans for health and the environment. These plans have identified the following two priorities: - identify and manage geographic areas where hotspot exposures are a potential risk to human health; and - reduce exposure inequalities. The aim of this study is to develop a spatial stochastic multimedia exposure model for detecting vulnerable populations and analyzing exposure determinants at a fine resolution and regional scale. A multimedia exposure model was developed by INERIS to assess the transfer of substances from the environment to humans through inhalation and ingestion pathways. The RESPIR project adds a spatial dimension by linking GIS (Geographic Information System) to the model. Tools are developed using modeling, spatial analysis and geostatistic methods to build and discretize interesting variables and indicators from different supports and resolutions on a 1-km(2) regular grid. We applied this model to the risk assessment of exposure to metals (cadmium, lead and nickel) using data from a region in France (Nord-Pas-de-Calais). The considered exposure pathways include the atmospheric contaminant inhalation and ingestion of soil, vegetation, meat, egg, milk, fish and drinking water. Exposure scenarios are defined for different reference groups (age, dietary properties, and the fraction of food produced locally). The two largest risks correspond to an ancient industrial site (Metaleurop) and the Lille agglomeration. In these areas, cadmium, vegetation ingestion and soil contamination are the principal determinants of the computed risk. Copyright © 2012 Elsevier B.V. All rights reserved.

  10. Internalisation of external costs in the Polish power generation sector: A partial equilibrium model

    International Nuclear Information System (INIS)

    Kudelko, Mariusz

    2006-01-01

    This paper presents a methodical framework, which is the basis for the economic analysis of the mid-term planning of development of the Polish energy system. The description of the partial equilibrium model and its results are demonstrated for different scenarios applied. The model predicts the generation, investment and pricing of mid-term decisions that refer to the Polish electricity and heat markets. The current structure of the Polish energy sector is characterised by interactions between the supply and demand sides of the energy sector. The supply side regards possibilities to deliver fuels from domestic and import sources and their conversion through transformation processes. Public power plants, public CHP plants, industry CHP plants and municipal heat plants represent the main producers of energy in Poland. Demand is characterised by the major energy consumers, i.e. industry and construction, transport, agriculture, trade and services, individual consumers and export. The relationships between the domestic electricity and heat markets are modelled taking into account external costs estimates. The volume and structure of energy production, electricity and heat prices, emissions, external costs and social welfare of different scenarios are presented. Results of the model demonstrate that the internalisation of external costs through the increase in energy prices implies significant improvement in social welfare

  11. External validation of the Cairns Prediction Model (CPM) to predict conversion from laparoscopic to open cholecystectomy.

    Science.gov (United States)

    Hu, Alan Shiun Yew; Donohue, Peter O'; Gunnarsson, Ronny K; de Costa, Alan

    2018-03-14

    Valid and user-friendly prediction models for conversion to open cholecystectomy allow for proper planning prior to surgery. The Cairns Prediction Model (CPM) has been in use clinically in the original study site for the past three years, but has not been tested at other sites. A retrospective, single-centred study collected ultrasonic measurements and clinical variables alongside with conversion status from consecutive patients who underwent laparoscopic cholecystectomy from 2013 to 2016 in The Townsville Hospital, North Queensland, Australia. An area under the curve (AUC) was calculated to externally validate of the CPM. Conversion was necessary in 43 (4.2%) out of 1035 patients. External validation showed an area under the curve of 0.87 (95% CI 0.82-0.93, p = 1.1 × 10 -14 ). In comparison with most previously published models, which have an AUC of approximately 0.80 or less, the CPM has the highest AUC of all published prediction models both for internal and external validation. Crown Copyright © 2018. Published by Elsevier Inc. All rights reserved.

  12. Comparison of modeling approaches to prioritize chemicals based on estimates of exposure and exposure potential.

    Science.gov (United States)

    Mitchell, Jade; Arnot, Jon A; Jolliet, Olivier; Georgopoulos, Panos G; Isukapalli, Sastry; Dasgupta, Surajit; Pandian, Muhilan; Wambaugh, John; Egeghy, Peter; Cohen Hubal, Elaine A; Vallero, Daniel A

    2013-08-01

    While only limited data are available to characterize the potential toxicity of over 8 million commercially available chemical substances, there is even less information available on the exposure and use-scenarios that are required to link potential toxicity to human and ecological health outcomes. Recent improvements and advances such as high throughput data gathering, high performance computational capabilities, and predictive chemical inherency methodology make this an opportune time to develop an exposure-based prioritization approach that can systematically utilize and link the asymmetrical bodies of knowledge for hazard and exposure. In response to the US EPA's need to develop novel approaches and tools for rapidly prioritizing chemicals, a "Challenge" was issued to several exposure model developers to aid the understanding of current systems in a broader sense and to assist the US EPA's effort to develop an approach comparable to other international efforts. A common set of chemicals were prioritized under each current approach. The results are presented herein along with a comparative analysis of the rankings of the chemicals based on metrics of exposure potential or actual exposure estimates. The analysis illustrates the similarities and differences across the domains of information incorporated in each modeling approach. The overall findings indicate a need to reconcile exposures from diffuse, indirect sources (far-field) with exposures from directly, applied chemicals in consumer products or resulting from the presence of a chemical in a microenvironment like a home or vehicle. Additionally, the exposure scenario, including the mode of entry into the environment (i.e. through air, water or sediment) appears to be an important determinant of the level of agreement between modeling approaches. Copyright © 2013 Elsevier B.V. All rights reserved.

  13. Comparison of modeling approaches to prioritize chemicals based on estimates of exposure and exposure potential

    Science.gov (United States)

    Mitchell, Jade; Arnot, Jon A.; Jolliet, Olivier; Georgopoulos, Panos G.; Isukapalli, Sastry; Dasgupta, Surajit; Pandian, Muhilan; Wambaugh, John; Egeghy, Peter; Cohen Hubal, Elaine A.; Vallero, Daniel A.

    2014-01-01

    While only limited data are available to characterize the potential toxicity of over 8 million commercially available chemical substances, there is even less information available on the exposure and use-scenarios that are required to link potential toxicity to human and ecological health outcomes. Recent improvements and advances such as high throughput data gathering, high performance computational capabilities, and predictive chemical inherency methodology make this an opportune time to develop an exposure-based prioritization approach that can systematically utilize and link the asymmetrical bodies of knowledge for hazard and exposure. In response to the US EPA’s need to develop novel approaches and tools for rapidly prioritizing chemicals, a “Challenge” was issued to several exposure model developers to aid the understanding of current systems in a broader sense and to assist the US EPA’s effort to develop an approach comparable to other international efforts. A common set of chemicals were prioritized under each current approach. The results are presented herein along with a comparative analysis of the rankings of the chemicals based on metrics of exposure potential or actual exposure estimates. The analysis illustrates the similarities and differences across the domains of information incorporated in each modeling approach. The overall findings indicate a need to reconcile exposures from diffuse, indirect sources (far-field) with exposures from directly, applied chemicals in consumer products or resulting from the presence of a chemical in a microenvironment like a home or vehicle. Additionally, the exposure scenario, including the mode of entry into the environment (i.e. through air, water or sediment) appears to be an important determinant of the level of agreement between modeling approaches. PMID:23707726

  14. Exponential model normalization for electrical capacitance tomography with external electrodes under gap permittivity conditions

    International Nuclear Information System (INIS)

    Baidillah, Marlin R; Takei, Masahiro

    2017-01-01

    A nonlinear normalization model which is called exponential model for electrical capacitance tomography (ECT) with external electrodes under gap permittivity conditions has been developed. The exponential model normalization is proposed based on the inherently nonlinear relationship characteristic between the mixture permittivity and the measured capacitance due to the gap permittivity of inner wall. The parameters of exponential equation are derived by using an exponential fitting curve based on the simulation and a scaling function is added to adjust the experiment system condition. The exponential model normalization was applied to two dimensional low and high contrast dielectric distribution phantoms by using simulation and experimental studies. The proposed normalization model has been compared with other normalization models i.e. Parallel, Series, Maxwell and Böttcher models. Based on the comparison of image reconstruction results, the exponential model is reliable to predict the nonlinear normalization of measured capacitance in term of low and high contrast dielectric distribution. (paper)

  15. Integrated reservoir characterization: Improvement in heterogeneities stochastic modelling by integration of additional external constraints

    Energy Technology Data Exchange (ETDEWEB)

    Doligez, B.; Eschard, R. [Institut Francais du Petrole, Rueil Malmaison (France); Geffroy, F. [Centre de Geostatistique, Fontainebleau (France)] [and others

    1997-08-01

    The classical approach to construct reservoir models is to start with a fine scale geological model which is informed with petrophysical properties. Then scaling-up techniques allow to obtain a reservoir model which is compatible with the fluid flow simulators. Geostatistical modelling techniques are widely used to build the geological models before scaling-up. These methods provide equiprobable images of the area under investigation, which honor the well data, and which variability is the same than the variability computed from the data. At an appraisal phase, when few data are available, or when the wells are insufficient to describe all the heterogeneities and the behavior of the field, additional constraints are needed to obtain a more realistic geological model. For example, seismic data or stratigraphic models can provide average reservoir information with an excellent areal coverage, but with a poor vertical resolution. New advances in modelisation techniques allow now to integrate this type of additional external information in order to constrain the simulations. In particular, 2D or 3D seismic derived information grids, or sand-shale ratios maps coming from stratigraphic models can be used as external drifts to compute the geological image of the reservoir at the fine scale. Examples are presented to illustrate the use of these new tools, their impact on the final reservoir model, and their sensitivity to some key parameters.

  16. Development of a spatial stochastic multimedia exposure model to assess population exposure at a regional scale

    Energy Technology Data Exchange (ETDEWEB)

    Caudeville, Julien, E-mail: Julien.CAUDEVILLE@ineris.fr [INERIS (French National Institute for Industrial Environment and Risks), Parc Technologique Alata, BP 2, 60550 Verneuil-en-Halatte (France); Joint research unit UMR 6599, Heudiasyc (Heuristic and Diagnoses of Complex Systems), University of Technology of Compiegne and CNRS, Rue du Dr Schweitzer, 60200 Compiegne (France); Bonnard, Roseline, E-mail: Roseline.BONNARD@ineris.fr [INERIS (French National Institute for Industrial Environment and Risks), Parc Technologique Alata, BP 2, 60550 Verneuil-en-Halatte (France); Boudet, Celine, E-mail: Celine.BOUDET@ineris.fr [INERIS (French National Institute for Industrial Environment and Risks), Parc Technologique Alata, BP 2, 60550 Verneuil-en-Halatte (France); Denys, Sebastien, E-mail: Sebastien.DENYS@ineris.fr [INERIS (French National Institute for Industrial Environment and Risks), Parc Technologique Alata, BP 2, 60550 Verneuil-en-Halatte (France); Govaert, Gerard, E-mail: gerard.govaert@utc.fr [Joint research unit UMR 6599, Heudiasyc (Heuristic and Diagnoses of Complex Systems), University of Technology of Compiegne and CNRS, Rue du Dr Schweitzer, 60200 Compiegne (France); Cicolella, Andre, E-mail: Andre.CICOLELLA@ineris.fr [INERIS (French National Institute for Industrial Environment and Risks), Parc Technologique Alata, BP 2, 60550 Verneuil-en-Halatte (France)

    2012-08-15

    Analyzing the relationship between the environment and health has become a major focus of public health efforts in France, as evidenced by the national action plans for health and the environment. These plans have identified the following two priorities: -identify and manage geographic areas where hotspot exposures are a potential risk to human health; and -reduce exposure inequalities. The aim of this study is to develop a spatial stochastic multimedia exposure model for detecting vulnerable populations and analyzing exposure determinants at a fine resolution and regional scale. A multimedia exposure model was developed by INERIS to assess the transfer of substances from the environment to humans through inhalation and ingestion pathways. The RESPIR project adds a spatial dimension by linking GIS (Geographic Information System) to the model. Tools are developed using modeling, spatial analysis and geostatistic methods to build and discretize interesting variables and indicators from different supports and resolutions on a 1-km{sup 2} regular grid. We applied this model to the risk assessment of exposure to metals (cadmium, lead and nickel) using data from a region in France (Nord-Pas-de-Calais). The considered exposure pathways include the atmospheric contaminant inhalation and ingestion of soil, vegetation, meat, egg, milk, fish and drinking water. Exposure scenarios are defined for different reference groups (age, dietary properties, and the fraction of food produced locally). The two largest risks correspond to an ancient industrial site (Metaleurop) and the Lille agglomeration. In these areas, cadmium, vegetation ingestion and soil contamination are the principal determinants of the computed risk. -- Highlights: Black-Right-Pointing-Pointer We present a multimedia exposure model for mapping environmental disparities. Black-Right-Pointing-Pointer We perform a risk assessment on a region of France at a fine scale for three metals. Black-Right-Pointing-Pointer We

  17. Study of deformation of droplet in external force field by using liquid-gas model of lattice-gas

    International Nuclear Information System (INIS)

    Ebihara, Ken-ichi; Watanabe, Tadashi

    2000-10-01

    The deformation of the droplet by the external force which is assumed to be gravity is studied by using the liquid-gas model of lattice-gas. Two types of liquid-gas models, one is the minimal model and the other is the maximal model, which are distinguished from each other by the added long-range interactions are used for the simulation of the droplet deformation. The difference of the droplet deformation between the maximal model and the minimal model was observed. While the droplet of the minimal model elongates in the direction of the external force, the droplet of the maximal model elongates in the perpendicular direction to the external force. Therefore the droplet deformation in the external force field of the maximal model is more similar to the droplet deformation which is observed in experiments than that of the minimal model. (author)

  18. Separation of variables in anisotropic models: anisotropic Rabi and elliptic Gaudin model in an external magnetic field

    Science.gov (United States)

    Skrypnyk, T.

    2017-08-01

    We study the problem of separation of variables for classical integrable Hamiltonian systems governed by non-skew-symmetric non-dynamical so(3)\\otimes so(3) -valued elliptic r-matrices with spectral parameters. We consider several examples of such models, and perform separation of variables for classical anisotropic one- and two-spin Gaudin-type models in an external magnetic field, and for Jaynes-Cummings-Dicke-type models without the rotating wave approximation.

  19. Assessing the external validity of model-based estimates of the incidence of heart attack in England: a modelling study

    Directory of Open Access Journals (Sweden)

    Peter Scarborough

    2016-11-01

    Full Text Available Abstract Background The DisMod II model is designed to estimate epidemiological parameters on diseases where measured data are incomplete and has been used to provide estimates of disease incidence for the Global Burden of Disease study. We assessed the external validity of the DisMod II model by comparing modelled estimates of the incidence of first acute myocardial infarction (AMI in England in 2010 with estimates derived from a linked dataset of hospital records and death certificates. Methods Inputs for DisMod II were prevalence rates of ever having had an AMI taken from a population health survey, total mortality rates and AMI mortality rates taken from death certificates. By definition, remission rates were zero. We estimated first AMI incidence in an external dataset from England in 2010 using a linked dataset including all hospital admissions and death certificates since 1998. 95 % confidence intervals were derived around estimates from the external dataset and DisMod II estimates based on sampling variance and reported uncertainty in prevalence estimates respectively. Results Estimates of the incidence rate for the whole population were higher in the DisMod II results than the external dataset (+54 % for men and +26 % for women. Age-specific results showed that the DisMod II results over-estimated incidence for all but the oldest age groups. Confidence intervals for the DisMod II and external dataset estimates did not overlap for most age groups. Conclusion By comparison with AMI incidence rates in England, DisMod II did not achieve external validity for age-specific incidence rates, but did provide global estimates of incidence that are of similar magnitude to measured estimates. The model should be used with caution when estimating age-specific incidence rates.

  20. Measuring and modeling exposure from environmental radiation on tidal flats

    International Nuclear Information System (INIS)

    Gould, T.J.; Hess, C.T.

    2005-01-01

    To examine the shielding effects of the tide cycle, a high pressure ion chamber was used to measure the exposure rate from environmental radiation on tidal flats. A theoretical model is derived to predict the behavior of exposure rate as a function of time for a detector placed one meter above ground on a tidal flat. The numerical integration involved in this derivation results in an empirical formula which implies exposure rate ∝tan-1(sint). We propose that calculating the total exposure incurred on a tidal flat requires measurements of only the slope of the tidal flat and the exposure rate when no shielding occurs. Experimental results are consistent with the model

  1. Literature review on induced exposure models, Task 2 HS-270

    Science.gov (United States)

    1982-02-01

    Sections 1, 2 and 3 of this report describe the development of : induced exposure models, together with d discussion of questions : of validity. These Sections focus on the most important and : relevant results from the literature, while Appendix A c...

  2. Computer simulation model of reflex e-beam systems coupled to an external circuit

    International Nuclear Information System (INIS)

    Jungwirth, K.; Stavinoha, P.

    1982-01-01

    Dynamics of ions and relativistic electrons in various high-voltage reflexing systems (reflex diodes and triodes) was investigated numerically by means of 1 1/2-dimensional PIC simulation model OREBIA. Its perfected version OREBIA-REX also accounts for system coupling to an external power source circuit, thus yielding the currents and applied voltage self-consistently. Various modes of operation of reflex diode and triode were studied using both models. It is shown that neglecting the influence of the external circuit can lead to seve--re overestimation of both ion currents and electron accumulation rates. In coupled systems with ions repeated collapses of impedance due to electron-ion relaxation processes are observed. The current and voltage pulses calculated for several reflex diodes and triodes with and without ions are presented. (J.U.)

  3. Measurement and modeling of external radiation during 1984 from LAMPF atmospheric emissions

    International Nuclear Information System (INIS)

    Bowen, B.M.; Olsen, W.A.; Van Etten, D.; Chen, I.

    1986-07-01

    An array of three portable, pressurized ionization chambers (PICs) measured short-term external radiation levels produced by air activation products from the Los Alamos Meson Physics Facility (LAMPF). The monitoring was at the closet offsite location, 700-900 m north and northeast of the source, and across a large, deep canyon. A Gaussian-type atmospheric dispersion model, using onsite meteorological and stack release data, was tested during their study. Monitoring results indicate that a persistent, local up-valley wind during the evening and early morning hours is largely responsible for causing the highest radiation levels to the northeast and north-northeast of LAMPF. Comparison of predicted and measured daily external radiation levels indicates a high degree of correlation. The model also gives accurate estimates of measured concentrations over longer periods of time

  4. A method for aggregating external operating conditions in multi-generation system optimization models

    DEFF Research Database (Denmark)

    Lythcke-Jørgensen, Christoffer Ernst; Münster, Marie; Ensinas, Adriano Viana

    2016-01-01

    This paper presents a novel, simple method for reducing external operating condition datasets to be used in multi-generation system optimization models. The method, called the Characteristic Operating Pattern (CHOP) method, is a visually-based aggregation method that clusters reference data based...... on parameter values rather than time of occurrence, thereby preserving important information on short-term relations between the relevant operating parameters. This is opposed to commonly used methods where data are averaged over chronological periods (months or years), and extreme conditions are hidden...... in the averaged values. The CHOP method is tested in a case study where the operation of a fictive Danish combined heat and power plant is optimized over a historical 5-year period. The optimization model is solved using the full external operating condition dataset, a reduced dataset obtained using the CHOP...

  5. Internal phase transition induced by external forces in Finsler geometric model for membranes

    Science.gov (United States)

    Koibuchi, Hiroshi; Shobukhov, Andrey

    2016-10-01

    In this paper, we numerically study an anisotropic shape transformation of membranes under external forces for two-dimensional triangulated surfaces on the basis of Finsler geometry. The Finsler metric is defined by using a vector field, which is the tangential component of a three-dimensional unit vector σ corresponding to the tilt or some external macromolecules on the surface of disk topology. The sigma model Hamiltonian is assumed for the tangential component of σ with the interaction coefficient λ. For large (small) λ, the surface becomes oblong (collapsed) at relatively small bending rigidity. For the intermediate λ, the surface becomes planar. Conversely, fixing the surface with the boundary of area A or with the two-point boundaries of distance L, we find that the variable σ changes from random to aligned state with increasing of A or L for the intermediate region of λ. This implies that an internal phase transition for σ is triggered not only by the thermal fluctuations, but also by external mechanical forces. We also find that the frame (string) tension shows the expected scaling behavior with respect to A/N (L/N) at the intermediate region of A (L) where the σ configuration changes between the disordered and ordered phases. Moreover, we find that the string tension γ at sufficiently large λ is considerably smaller than that at small λ. This phenomenon resembles the so-called soft-elasticity in the liquid crystal elastomer, which is deformed by small external tensile forces.

  6. A computer program for external modes in complex ionic crystals (the rigid molecular-ion model)

    International Nuclear Information System (INIS)

    Chaplot, S.L.

    1978-01-01

    A computer program DISPR has been developed to calculate the external mode phonon dispersion relation in the harmonic approximation for complex ionic crystals using the rigid molecular ion model. A description of the program, the flow diagram and the required input information are given. A sample calculation for α-KNO 3 is presented. The program can handle any type of crystal lattice with any number of atoms and molecules per unit cell with suitable changes in dimension statements. (M.G.B.)

  7. Comorbidities and continuities as ontogenic processes: Toward a developmental spectrum model of externalizing psychopathology

    Science.gov (United States)

    Beauchaine, Theodore P.; McNulty, Tiffany

    2014-01-01

    Research on child and adolescent mental health problems has burgeoned since the inaugural issue of Development and Psychopathology was published in 1989. In the quarter century since, static models of psychopathology have been abandoned in favor of transactional models, following the agenda set by editor Dante Cicchetti and other proponents of the discipline. The transactional approach, which has been applied to autism, depression, self-injury, and delinquency, (a) specifies vulnerabilities and risk factors across multiple levels of analysis spanning genes to cultures, (b) identifies multifinal and equifinal pathways to psychopathology, and (c) transcends traditional disciplinary boundaries. However, as noted by Rutter and Sroufe (2000), specific mechanisms of continuity, discontinuity, and comorbidity of psychopathology must be identified if we wish to understand etiology fully. In this article, we present a model of early-onset externalizing behavior in which comorbidities and continuities are viewed as ontogenic processes: products of complex longitudinal transactions between interdependent individual-level vulnerabilities (e.g., genetic, epigenetic, allostatic) and equally interdependent contextual risk factors (e.g., coercive parenting, deviant peer group affiliations, neighborhood criminality). Through interactions across levels of analysis, some individuals traverse along the externalizing spectrum, beginning with heritable trait impulsivity in preschool and ending in antisociality in adulthood. In describing our model, we note that (a) the approach outlined in the DSM to subtyping externalizing disorders continues to obscure developmental pathways to antisociality, (b) molecular genetics studies will likely not identify meaningful subtypes of externalizing disorder, and (c) ontogenic trait approaches to psychopathology are much more likely to advance the discipline in upcoming years. PMID:24342853

  8. Comprehensive European dietary exposure model (CEDEM) for food additives.

    Science.gov (United States)

    Tennant, David R

    2016-05-01

    European methods for assessing dietary exposures to nutrients, additives and other substances in food are limited by the availability of detailed food consumption data for all member states. A proposed comprehensive European dietary exposure model (CEDEM) applies summary data published by the European Food Safety Authority (EFSA) in a deterministic model based on an algorithm from the EFSA intake method for food additives. The proposed approach can predict estimates of food additive exposure provided in previous EFSA scientific opinions that were based on the full European food consumption database.

  9. Study of anticipated impact on DOE programs from proposed reductions to the external occupational radiation exposure limit

    International Nuclear Information System (INIS)

    1978-01-01

    Many years of radiation exposure experience in all phases of nuclear energy applications were surveyed to evaluate the impact of reducing the present DOE limit of 5 rem/yr. Conclusions drawn are: (1) Reduction of the occupational exposure limit would result in significant increase in total accumulated exposure to the current radiation worker population and could require an increase in the work force with attending personnel and administrative problems. (2) Important programs/facilities would have to be abandoned. (3) Some engineering technology is not sufficiently developed to design or operate at the 0.5 rem/yr limit. (4) Exposure reduction to 2.5 rem/yr would significantly increase costs and would result in a small increase in total exposure to the work force. (5) Significant initial capital cost plus increased annual costs would result. (6) The major emphasis in controlling occupational exposure should be on continued work toward further reduction of total man-rem. This should involve continued development of ALAP programs along with improvements in dose measurement and recording methods, more sophisticated exposure records, and containment, handling and remote maintenance techniques. (7) Radiation protection practices at DOE facilities have maintained exposures of the bulk of the nuclear work force substantially below current limits for many years. (8) The current standards of 5 rem/yr is used only as a limit. For example, 97% of the employees receive less than 0.5 rem/yr

  10. External gear pumps operating with non-Newtonian fluids: Modelling and experimental validation

    Science.gov (United States)

    Rituraj, Fnu; Vacca, Andrea

    2018-06-01

    External Gear Pumps are used in various industries to pump non-Newtonian viscoelastic fluids like plastics, paints, inks, etc. For both design and analysis purposes, it is often a matter of interest to understand the features of the displacing action realized by meshing of the gears and the description of the behavior of the leakages for this kind of pumps. However, very limited work can be found in literature about methodologies suitable to model such phenomena. This article describes the technique of modelling external gear pumps that operate with non-Newtonian fluids. In particular, it explains how the displacing action of the unit can be modelled using a lumped parameter approach which involves dividing fluid domain into several control volumes and internal flow connections. This work is built upon the HYGESim simulation tool, conceived by the authors' research team in the last decade, which is for the first time extended for the simulation of non-Newtonian fluids. The article also describes several comparisons between simulation results and experimental data obtained from numerous experiments performed for validation of the presented methodology. Finally, operation of external gear pump with fluids having different viscosity characteristics is discussed.

  11. Modeling Exposure to Persistent Chemicals in Hazard and Risk Assessment

    Energy Technology Data Exchange (ETDEWEB)

    Cowan-Ellsberry, Christina E.; McLachlan, Michael S.; Arnot, Jon A.; MacLeod, Matthew; McKone, Thomas E.; Wania, Frank

    2008-11-01

    Fate and exposure modeling has not thus far been explicitly used in the risk profile documents prepared to evaluate significant adverse effect of candidate chemicals for either the Stockholm Convention or the Convention on Long-Range Transboundary Air Pollution. However, we believe models have considerable potential to improve the risk profiles. Fate and exposure models are already used routinely in other similar regulatory applications to inform decisions, and they have been instrumental in building our current understanding of the fate of POP and PBT chemicals in the environment. The goal of this paper is to motivate the use of fate and exposure models in preparing risk profiles in the POP assessment procedure by providing strategies for incorporating and using models. The ways that fate and exposure models can be used to improve and inform the development of risk profiles include: (1) Benchmarking the ratio of exposure and emissions of candidate chemicals to the same ratio for known POPs, thereby opening the possibility of combining this ratio with the relative emissions and relative toxicity to arrive at a measure of relative risk. (2) Directly estimating the exposure of the environment, biota and humans to provide information to complement measurements, or where measurements are not available or are limited. (3) To identify the key processes and chemical and/or environmental parameters that determine the exposure; thereby allowing the effective prioritization of research or measurements to improve the risk profile. (4) Predicting future time trends including how quickly exposure levels in remote areas would respond to reductions in emissions. Currently there is no standardized consensus model for use in the risk profile context. Therefore, to choose the appropriate model the risk profile developer must evaluate how appropriate an existing model is for a specific setting and whether the assumptions and input data are relevant in the context of the application

  12. Modeling exposure to persistent chemicals in hazard and risk assessment.

    Science.gov (United States)

    Cowan-Ellsberry, Christina E; McLachlan, Michael S; Arnot, Jon A; Macleod, Matthew; McKone, Thomas E; Wania, Frank

    2009-10-01

    Fate and exposure modeling has not, thus far, been explicitly used in the risk profile documents prepared for evaluating the significant adverse effect of candidate chemicals for either the Stockholm Convention or the Convention on Long-Range Transboundary Air Pollution. However, we believe models have considerable potential to improve the risk profiles. Fate and exposure models are already used routinely in other similar regulatory applications to inform decisions, and they have been instrumental in building our current understanding of the fate of persistent organic pollutants (POP) and persistent, bioaccumulative, and toxic (PBT) chemicals in the environment. The goal of this publication is to motivate the use of fate and exposure models in preparing risk profiles in the POP assessment procedure by providing strategies for incorporating and using models. The ways that fate and exposure models can be used to improve and inform the development of risk profiles include 1) benchmarking the ratio of exposure and emissions of candidate chemicals to the same ratio for known POPs, thereby opening the possibility of combining this ratio with the relative emissions and relative toxicity to arrive at a measure of relative risk; 2) directly estimating the exposure of the environment, biota, and humans to provide information to complement measurements or where measurements are not available or are limited; 3) to identify the key processes and chemical or environmental parameters that determine the exposure, thereby allowing the effective prioritization of research or measurements to improve the risk profile; and 4) forecasting future time trends, including how quickly exposure levels in remote areas would respond to reductions in emissions. Currently there is no standardized consensus model for use in the risk profile context. Therefore, to choose the appropriate model the risk profile developer must evaluate how appropriate an existing model is for a specific setting and

  13. Problems with regard to occupational exposure of external personnel (section 15 of the German Radiation Protection Ordinance)

    International Nuclear Information System (INIS)

    Roth, W.

    2002-01-01

    The annual radiation dose to the group of external personnel working in nuclear facilities accounts for more than 39% of the total annual collective dose of all occupationally exposed persons in Germany. This is a fact causing problems for plant operators employing external personnel as well as the sending companies, with respect to compliance with the radiation protection regulations. The amended German Radiation Protection Ordinance does not really make things easier in this respect, but in fact is expected to aggravate the situation in the course of increasing globalisation in the industrial sector. (orig./CB) [de

  14. Modelling of individual subject ozone exposure response kinetics.

    Science.gov (United States)

    Schelegle, Edward S; Adams, William C; Walby, William F; Marion, M Susan

    2012-06-01

    A better understanding of individual subject ozone (O(3)) exposure response kinetics will provide insight into how to improve models used in the risk assessment of ambient ozone exposure. To develop a simple two compartment exposure-response model that describes individual subject decrements in forced expiratory volume in one second (FEV(1)) induced by the acute inhalation of O(3) lasting up to 8 h. FEV(1) measurements of 220 subjects who participated in 14 previously completed studies were fit to the model using both particle swarm and nonlinear least squares optimization techniques to identify three subject-specific coefficients producing minimum "global" and local errors, respectively. Observed and predicted decrements in FEV(1) of the 220 subjects were used for validation of the model. Further validation was provided by comparing the observed O(3)-induced FEV(1) decrements in an additional eight studies with predicted values obtained using model coefficients estimated from the 220 subjects used in cross validation. Overall the individual subject measured and modeled FEV(1) decrements were highly correlated (mean R(2) of 0.69 ± 0.24). In addition, it was shown that a matrix of individual subject model coefficients can be used to predict the mean and variance of group decrements in FEV(1). This modeling approach provides insight into individual subject O(3) exposure response kinetics and provides a potential starting point for improving the risk assessment of environmental O(3) exposure.

  15. Integration Of Externalized Decision Models In The Definition Of Workflows For Digital Pathology

    Directory of Open Access Journals (Sweden)

    J. van Leeuwen

    2016-06-01

    We proposed a workflow solution enabling the representation of decision models as externalized executable tasks in the process definition. Our approach separates the task implementations from the workflow model, ensuring scalability and allowing for the inclusion of complex decision logic in the workflow execution. In we depict a simplified model of a pathology diagnosis workflow (starting with the digitization of the slides, represented according to the BPMN modeling conventions. The example shows a workflow sequence that automatically orders a HER2 FISH when IHC is borderline according to defined customizable thresholds. The process model integrates an image analysis algorithm that scores images. Based on the score and the thresholds the decision model evaluates the condition and recommends the pre-ordering of an additional test when the score falls between the two thresholds. This leads to faster diagnosis and allows balancing the costs of an additional test versus the overhead of the pathologist by choosing the values of the thresholds.  

  16. Modelling survival: exposure pattern, species sensitivity and uncertainty.

    Science.gov (United States)

    Ashauer, Roman; Albert, Carlo; Augustine, Starrlight; Cedergreen, Nina; Charles, Sandrine; Ducrot, Virginie; Focks, Andreas; Gabsi, Faten; Gergs, André; Goussen, Benoit; Jager, Tjalling; Kramer, Nynke I; Nyman, Anna-Maija; Poulsen, Veronique; Reichenberger, Stefan; Schäfer, Ralf B; Van den Brink, Paul J; Veltman, Karin; Vogel, Sören; Zimmer, Elke I; Preuss, Thomas G

    2016-07-06

    The General Unified Threshold model for Survival (GUTS) integrates previously published toxicokinetic-toxicodynamic models and estimates survival with explicitly defined assumptions. Importantly, GUTS accounts for time-variable exposure to the stressor. We performed three studies to test the ability of GUTS to predict survival of aquatic organisms across different pesticide exposure patterns, time scales and species. Firstly, using synthetic data, we identified experimental data requirements which allow for the estimation of all parameters of the GUTS proper model. Secondly, we assessed how well GUTS, calibrated with short-term survival data of Gammarus pulex exposed to four pesticides, can forecast effects of longer-term pulsed exposures. Thirdly, we tested the ability of GUTS to estimate 14-day median effect concentrations of malathion for a range of species and use these estimates to build species sensitivity distributions for different exposure patterns. We find that GUTS adequately predicts survival across exposure patterns that vary over time. When toxicity is assessed for time-variable concentrations species may differ in their responses depending on the exposure profile. This can result in different species sensitivity rankings and safe levels. The interplay of exposure pattern and species sensitivity deserves systematic investigation in order to better understand how organisms respond to stress, including humans.

  17. Neurotoxicity in Preclinical Models of Occupational Exposure to Organophosphorus Compounds

    Science.gov (United States)

    Voorhees, Jaymie R.; Rohlman, Diane S.; Lein, Pamela J.; Pieper, Andrew A.

    2017-01-01

    Organophosphorus (OPs) compounds are widely used as insecticides, plasticizers, and fuel additives. These compounds potently inhibit acetylcholinesterase (AChE), the enzyme that inactivates acetylcholine at neuronal synapses, and acute exposure to high OP levels can cause cholinergic crisis in humans and animals. Evidence further suggests that repeated exposure to lower OP levels insufficient to cause cholinergic crisis, frequently encountered in the occupational setting, also pose serious risks to people. For example, multiple epidemiological studies have identified associations between occupational OP exposure and neurodegenerative disease, psychiatric illness, and sensorimotor deficits. Rigorous scientific investigation of the basic science mechanisms underlying these epidemiological findings requires valid preclinical models in which tightly-regulated exposure paradigms can be correlated with neurotoxicity. Here, we review the experimental models of occupational OP exposure currently used in the field. We found that animal studies simulating occupational OP exposures do indeed show evidence of neurotoxicity, and that utilization of these models is helping illuminate the mechanisms underlying OP-induced neurological sequelae. Still, further work is necessary to evaluate exposure levels, protection methods, and treatment strategies, which taken together could serve to modify guidelines for improving workplace conditions globally. PMID:28149268

  18. Modelling indoor exposure to natural radioactive nuclides

    International Nuclear Information System (INIS)

    Hofmann, W.; Daschil, F.

    1986-01-01

    Radon enters buildings from several sources primarily from building materials and from the soil or rocks that underlie or surround building fundaments. A multicompartment model was developed which describes the fate of radon and attached or free radon decay products in a model room by a set of linear time-dependent differential equations. Time-dependent coefficients allow to model temporal parameter changes, e.g. the opening of windows, or a sudden pressure drop leading to enhanced exhalation. While steady-state models were used to study the effect of parameter changes on steady state nuclide concentrations, the time-dependent models provided additional information on the time scale of these changes. (author)

  19. Underwater Sound Propagation Modeling Methods for Predicting Marine Animal Exposure.

    Science.gov (United States)

    Hamm, Craig A; McCammon, Diana F; Taillefer, Martin L

    2016-01-01

    The offshore exploration and production (E&P) industry requires comprehensive and accurate ocean acoustic models for determining the exposure of marine life to the high levels of sound used in seismic surveys and other E&P activities. This paper reviews the types of acoustic models most useful for predicting the propagation of undersea noise sources and describes current exposure models. The severe problems caused by model sensitivity to the uncertainty in the environment are highlighted to support the conclusion that it is vital that risk assessments include transmission loss estimates with statistical measures of confidence.

  20. Levels of {sup 131}I Activity in Patients to Enable Hospital Discharge, Based on External Exposure of Family Members of the Patient in Japan

    Energy Technology Data Exchange (ETDEWEB)

    Koshida, K.; Nishizawa, K.; Koga, S.; Orito, T

    1999-07-01

    The activity levels for discharge from hospital of patients treated with {sup 131}I in Japan are described. The level was determined by considering the public annual dose limit in Japan of 1 mSv and the possible exposure of family members with whom the patients were in daily contact. All analyses are based on a partner, where both the partner and the children will be subject to exposure. The external exposure was calculated by using the data on the distance between the patient and family members, the length of the time spent at each distance, and each member's age. It was assumed that the mother must continue to take responsibility for care of children during the period that she is radioactive. The conclusions of this work are that a maximum residual {sup 131}I radioactivity of <97 MBq, with a distance from the patient in bed greater than 50 cm and the ages of patient's children all over 1 year, will be required to ensure that the maximum dose to any contact will not exceed 1 mSv. More than 50 cm distance suggests either an unmarried housewife or the partner sleeping in an adjacent room or twin beds. No restriction is needed in respect of external exposure for patients with residual radioactivity of 42 MBq, although levels lower than this may be required where there is a risk of contamination, e.g. due to urinary incontinence. This conflicts with recommended activity levels for discharge (ICRP 25) of 560 MBq (for a dose limit of 5 mSv). The findings of this work are only directly relevant for the age range under 55 years. No account was taken in this paper of internal exposure from internal pathways. (author)

  1. Levels of 131I Activity in Patients to Enable Hospital Discharge, Based on External Exposure of Family Members of the Patient in Japan

    International Nuclear Information System (INIS)

    Koshida, K.; Nishizawa, K.; Koga, S.; Orito, T.

    1999-01-01

    The activity levels for discharge from hospital of patients treated with 131 I in Japan are described. The level was determined by considering the public annual dose limit in Japan of 1 mSv and the possible exposure of family members with whom the patients were in daily contact. All analyses are based on a partner, where both the partner and the children will be subject to exposure. The external exposure was calculated by using the data on the distance between the patient and family members, the length of the time spent at each distance, and each member's age. It was assumed that the mother must continue to take responsibility for care of children during the period that she is radioactive. The conclusions of this work are that a maximum residual 131 I radioactivity of <97 MBq, with a distance from the patient in bed greater than 50 cm and the ages of patient's children all over 1 year, will be required to ensure that the maximum dose to any contact will not exceed 1 mSv. More than 50 cm distance suggests either an unmarried housewife or the partner sleeping in an adjacent room or twin beds. No restriction is needed in respect of external exposure for patients with residual radioactivity of 42 MBq, although levels lower than this may be required where there is a risk of contamination, e.g. due to urinary incontinence. This conflicts with recommended activity levels for discharge (ICRP 25) of 560 MBq (for a dose limit of 5 mSv). The findings of this work are only directly relevant for the age range under 55 years. No account was taken in this paper of internal exposure from internal pathways. (author)

  2. TOURISM, TRADE, EXTERNALITIES, AND PUBLIC GOODS IN A THREE-SECTOR GROWTH MODEL

    Directory of Open Access Journals (Sweden)

    Wei-Bin Zhang

    2015-06-01

    Full Text Available The purpose of this study is to introduce tourism, externalities, and public goods to a small-open growth with endogenous wealth and public goods supply. We develop the model on the basis of the Solow-Uzawa growth model, the neoclassical neoclassical growth theory with externalities, and ideas from tourism economics. The economy consists of three – service, industrial, and public - sectors. The production side is based on the traditional growth theories, while the household behavior is described by an alternative utility function proposed by Zhang. We introduce endogenous land distribution between housing and supply of services. The industrial and service sectors are perfectly competitive subject to the government’s taxation. The public sector is financially supported by the government. We introduce taxes not only on producers, but also on consumers’ incomes from wage, land, and interest of wealth, consumption of goods and services, and housing. We simulate the motion of the national economy and show the existence of a unique stable equilibrium. We carry out comparative dynamic analysis with regard to the rate of interest in the global market, the total productivity of the service sector, tax rate on the service sector, tax rate on consumption of services, human capital, the propensity to consume services, and the impact of public services on the productivity of the industrial sector. The comparative dynamic analysis provides some important insights into the complexity of open economies with endogenous wealth, public goods, and externalities.

  3. New parameterization of external and induced fields in geomagnetic field modeling, and a candidate model for IGRF 2005

    DEFF Research Database (Denmark)

    Olsen, Nils; Sabaka, T.J.; Lowes, F.

    2005-01-01

    When deriving spherical harmonic models of the Earth's magnetic field, low-degree external field contributions are traditionally considered by assuming that their expansion coefficient q(1)(0) varies linearly with the D-st-index, while induced contributions are considered assuming a constant ratio...... Q(1) of induced to external coefficients. A value of Q(1) = 0.27 was found from Magsat data and has been used by several authors when deriving recent field models from Orsted and CHAMP data. We describe a new approach that considers external and induced field based on a separation of D-st = E-st + I......-st into external (E-st) and induced (I-st) parts using a 1D model of mantle conductivity. The temporal behavior of q(1)(0) and of the corresponding induced coefficient are parameterized by E-st and I-st, respectively. In addition, we account for baseline-instabilities of D-st by estimating a value of q(1...

  4. Spontaneously broken symmetry of vacuum in external gravitational fields of isotropic cosmological models

    International Nuclear Information System (INIS)

    Veryaskin, A.V.; Lapchinskij, V.G.; Nekrasov, V.I.; Rubakov, V.A.

    1981-01-01

    Behaviour of vacuum symmetry in the model of self-acting scalar field in the open and closed isotropic cosmological spaces is investigated. Considered are the cases with the mass squared of the scalar field m 2 >0, m 2 =0 and m 2 2 2 =0 at exponentially large scale factors the study of the problem on the behaviour of the symmetry requires exceeding the limits of the perturbation theory. The final behaviour of the vacuum symmetry in the open model at small radii depends on combined effect of all the external factors [ru

  5. THEORETICAL MODELING OF THE FEEDBACK STABILIZATION OF EXTERNAL MHD MODES IN TOROIDAL GEOMETRY

    International Nuclear Information System (INIS)

    CHANCE, M.S.; CHU, M.S.; OKABAYASHI, M.; TURNBULL, A.D.

    2001-02-01

    OAK-B135 A theoretical framework for understanding the feedback mechanism against external MHD modes has been formulated. Efficient computational tools--the GATO stability code coupled with a substantially modified VACUUM code--have been developed to effectively design viable feedback systems against these modes. The analysis assumed a thin resistive shell and a feedback coil structure accurately modeled in θ, with only a single harmonic variation in φ. Time constants and induced currents in the enclosing resistive shell are calculated. An optimized configuration based on an idealized model have been computed for the DIII-D device. Up to 90% of the effectiveness of an ideal wall can be achieved

  6. Improved External Base Resistance Extraction for Submicrometer InP/InGaAs DHBT Models

    DEFF Research Database (Denmark)

    Johansen, Tom Keinicke; Krozer, Viktor; Nodjiadjim, Virginie

    2011-01-01

    An improved direct parameter extraction method is proposed for III–V heterojunction bipolar transistor (HBT) external base resistance $R_{\\rm bx}$ extraction from forward active $S$-parameters. The method is formulated taking into account the current dependence of the intrinsic base–collector cap......An improved direct parameter extraction method is proposed for III–V heterojunction bipolar transistor (HBT) external base resistance $R_{\\rm bx}$ extraction from forward active $S$-parameters. The method is formulated taking into account the current dependence of the intrinsic base...... factor given as the ratio of the emitter to the collector area. The determination of the parameters $I_{p}$ and $X_{0}$ from experimental $S$-parameters is described. The method is applied to high-speed submicrometer InP/InGaAs DHBT devices and leads to small-signal equivalent circuit models, which...

  7. Ex vivo tracheomalacia model with 3D-printed external tracheal splint.

    Science.gov (United States)

    Kaye, Rachel; Goldstein, Todd; Aronowitz, Danielle; Grande, Daniel A; Zeltsman, David; Smith, Lee P

    2017-04-01

    To design and evaluate an ex vivo model of tracheomalacia with and without a three-dimensional (3D)-printed external tracheal splint. Prospective, ex vivo animal trial. Three groups of ex vivo porcine tracheas were used: 1) control (unmanipulated trachea), 2) tracheomalacia (tracheal rings partially incised and crushed), and 3) splinted tracheomalacia (external custom tracheal splint fitted onto group 2 trachea). Each end of an ex vivo trachea was sealed with a custom-designed and 3D-printed cap; a transducer was placed through one end to measure the pressure inside the trachea. Although the negative pressure was applied to the tracheal lumen, the tracheal wall collapse was measured externally and internally using a bronchoscope. Each group had at least three recorded trials. Tracheal diameter was evaluated using ImageJ software (National Institutes of Health, Bethesda, MD) and was averaged between two raters. Average tracheal occlusion percentage was compared using Student t test. The average occlusion was 31% for group 1, 87.4% for group 2, and 20% for group 3. Significant differences were found between the control and tracheomalacia groups (P tracheomalacia and splinted tracheomalacia groups (P tracheomalacia groups (P = 0.13). Applied pressure was plotted against occlusion and regression line slope differed between the tracheomalacia (0.91) and control (0.12) or splinted tracheomalacia (0.39) groups. We demonstrate the potential for an ex vivo tracheomalacia model to reproduce airway collapse and show that this collapse can be treated successfully with a 3D-printed external splint. These results are promising and justify further studies. N/A. Laryngoscope, 127:950-955, 2017. © 2016 The American Laryngological, Rhinological and Otological Society, Inc.

  8. Reconstruction of Exposure to m-Xylene from Human Biomonitoring Data Using PBPK Modelling, Bayesian Inference, and Markov Chain Monte Carlo Simulation

    Science.gov (United States)

    McNally, Kevin; Cotton, Richard; Cocker, John; Jones, Kate; Bartels, Mike; Rick, David; Price, Paul; Loizou, George

    2012-01-01

    There are numerous biomonitoring programs, both recent and ongoing, to evaluate environmental exposure of humans to chemicals. Due to the lack of exposure and kinetic data, the correlation of biomarker levels with exposure concentrations leads to difficulty in utilizing biomonitoring data for biological guidance values. Exposure reconstruction or reverse dosimetry is the retrospective interpretation of external exposure consistent with biomonitoring data. We investigated the integration of physiologically based pharmacokinetic modelling, global sensitivity analysis, Bayesian inference, and Markov chain Monte Carlo simulation to obtain a population estimate of inhalation exposure to m-xylene. We used exhaled breath and venous blood m-xylene and urinary 3-methylhippuric acid measurements from a controlled human volunteer study in order to evaluate the ability of our computational framework to predict known inhalation exposures. We also investigated the importance of model structure and dimensionality with respect to its ability to reconstruct exposure. PMID:22719759

  9. Reconstruction of Exposure to m-Xylene from Human Biomonitoring Data Using PBPK Modelling, Bayesian Inference, and Markov Chain Monte Carlo Simulation

    Directory of Open Access Journals (Sweden)

    Kevin McNally

    2012-01-01

    Full Text Available There are numerous biomonitoring programs, both recent and ongoing, to evaluate environmental exposure of humans to chemicals. Due to the lack of exposure and kinetic data, the correlation of biomarker levels with exposure concentrations leads to difficulty in utilizing biomonitoring data for biological guidance values. Exposure reconstruction or reverse dosimetry is the retrospective interpretation of external exposure consistent with biomonitoring data. We investigated the integration of physiologically based pharmacokinetic modelling, global sensitivity analysis, Bayesian inference, and Markov chain Monte Carlo simulation to obtain a population estimate of inhalation exposure to m-xylene. We used exhaled breath and venous blood m-xylene and urinary 3-methylhippuric acid measurements from a controlled human volunteer study in order to evaluate the ability of our computational framework to predict known inhalation exposures. We also investigated the importance of model structure and dimensionality with respect to its ability to reconstruct exposure.

  10. Study of anticipated impact on DOE programs from proposed reductions to the external occupational radiation exposure limit

    International Nuclear Information System (INIS)

    1981-02-01

    A study of the impact of reducing the occupational radiation exposure limit from 5 rem/yr to 2.5, 1.0 and 0.5 rem/yr, respectively produced the following conclusions: reduction of the occupational exposure limit would result in significant increase in total accumulated exposure to the current radiation worker population and could require an increase in the work force; important programs would have to be abandoned at a planned exposure limit of 0.5 rem/yr; some engineering technology is not sufficiently developed to design or operate at the 0.5 rem/yr limit; even a factor of 2 reduction (2.5 rem/yr) would significantly increase costs and would result in an increase in total exposure to the work force; in addition to a significant one-time initial capital cost resulting from a 0.5 rem/yr limit, there would be a significant increase in annual costs; the major emphasis in controlling occupational exposure should be on further reduction of total man-rem; and current standards are used only as a limit. For example, 97% of the employees receive less than 0.5 rem/yr

  11. Thermodynamic Model for Updraft Gasifier with External Recirculation of Pyrolysis Gas

    Directory of Open Access Journals (Sweden)

    Fajri Vidian

    2016-01-01

    Full Text Available Most of the thermodynamic modeling of gasification for updraft gasifier uses one process of decomposition (decomposition of fuel. In the present study, a thermodynamic model which uses two processes of decomposition (decomposition of fuel and char is used. The model is implemented in modification of updraft gasifier with external recirculation of pyrolysis gas to the combustion zone and the gas flowing out from the side stream (reduction zone in the updraft gasifier. The goal of the model obtains the influences of amount of recirculation pyrolysis gas fraction to combustion zone on combustible gas and tar. The significant results of modification updraft are that the increases amount of recirculation of pyrolysis gas will increase the composition of H2 and reduce the composition of tar; then the composition of CO and CH4 is dependent on equivalence ratio. The results of the model for combustible gas composition are compared with previous study.

  12. Hydroquinone PBPK model refinement and application to dermal exposure.

    Science.gov (United States)

    Poet, Torka S; Carlton, Betsy D; Deyo, James A; Hinderliter, Paul M

    2010-11-01

    A physiologically based pharmacokinetic (PBPK) model for hydroquinone (HQ) was refined to include an expanded description of HQ-glucuronide metabolites and a description of dermal exposures to support route-to-route and cross-species extrapolation. Total urinary excretion of metabolites from in vivo rat dermal exposures was used to estimate a percutaneous permeability coefficient (K(p); 3.6×10(-5) cm/h). The human in vivo K(p) was estimated to be 1.62×10(-4) cm/h, based on in vitro skin permeability data in rats and humans and rat in vivo values. The projected total multi-substituted glutathione (which was used as an internal dose surrogate for the toxic glutathione metabolites) was modeled following an exposure scenario based on submersion of both hands in a 5% aqueous solution of HQ (similar to black and white photographic developing solution) for 2 h, a worst-case exposure scenario. Total multi-substituted glutathione following this human dermal exposure scenario was several orders of magnitude lower than the internal total glutathione conjugates in rats following an oral exposure to the rat NOEL of 20 mg/kg. Thus, under more realistic human dermal exposure conditions, it is unlikely that toxic glutathione conjugates (primarily the di- and, to a lesser degree, the tri-glutathione conjugate) will reach significant levels in target tissues. Copyright © 2010. Published by Elsevier Ltd.

  13. Concurrence of Quantum States: Algebraic Dynamical Method Study XXX Models in a Time-Depending Random External Field

    International Nuclear Information System (INIS)

    Fu Chuanji; Zhu Qinsheng; Wu Shaoyi

    2010-01-01

    Based on algebraic dynamics and the concept of the concurrence of the entanglement, we investigate the evolutive properties of the two-qubit entanglement that formed by Heisenberg XXX models under a time-depending external held. For this system, the property of the concurrence that is only dependent on the coupling constant J and total values of the external field is proved. Furthermore, we found that the thermal concurrence of the system under a static random external field is a function of the coupling constant J, temperature T, and the magnitude of external held. (general)

  14. Modeling population exposures to silver nanoparticles present in consumer products

    Science.gov (United States)

    Royce, Steven G.; Mukherjee, Dwaipayan; Cai, Ting; Xu, Shu S.; Alexander, Jocelyn A.; Mi, Zhongyuan; Calderon, Leonardo; Mainelis, Gediminas; Lee, KiBum; Lioy, Paul J.; Tetley, Teresa D.; Chung, Kian Fan; Zhang, Junfeng; Georgopoulos, Panos G.

    2014-11-01

    Exposures of the general population to manufactured nanoparticles (MNPs) are expected to keep rising due to increasing use of MNPs in common consumer products (PEN 2014). The present study focuses on characterizing ambient and indoor population exposures to silver MNPs (nAg). For situations where detailed, case-specific exposure-related data are not available, as in the present study, a novel tiered modeling system, Prioritization/Ranking of Toxic Exposures with GIS (geographic information system) Extension (PRoTEGE), has been developed: it employs a product life cycle analysis (LCA) approach coupled with basic human life stage analysis (LSA) to characterize potential exposures to chemicals of current and emerging concern. The PRoTEGE system has been implemented for ambient and indoor environments, utilizing available MNP production, usage, and properties databases, along with laboratory measurements of potential personal exposures from consumer spray products containing nAg. Modeling of environmental and microenvironmental levels of MNPs employs probabilistic material flow analysis combined with product LCA to account for releases during manufacturing, transport, usage, disposal, etc. Human exposure and dose characterization further employ screening microenvironmental modeling and intake fraction methods combined with LSA for potentially exposed populations, to assess differences associated with gender, age, and demographics. Population distributions of intakes, estimated using the PRoTEGE framework, are consistent with published individual-based intake estimates, demonstrating that PRoTEGE is capable of capturing realistic exposure scenarios for the US population. Distributions of intakes are also used to calculate biologically relevant population distributions of uptakes and target tissue doses through human airway dosimetry modeling that takes into account product MNP size distributions and age-relevant physiological parameters.

  15. Large-scale external validation and comparison of prognostic models: an application to chronic obstructive pulmonary disease

    NARCIS (Netherlands)

    Guerra, Beniamino; Haile, Sarah R.; Lamprecht, Bernd; Ramírez, Ana S.; Martinez-Camblor, Pablo; Kaiser, Bernhard; Alfageme, Inmaculada; Almagro, Pere; Casanova, Ciro; Esteban-González, Cristóbal; Soler-Cataluña, Juan J.; de-Torres, Juan P.; Miravitlles, Marc; Celli, Bartolome R.; Marin, Jose M.; ter Riet, Gerben; Sobradillo, Patricia; Lange, Peter; Garcia-Aymerich, Judith; Antó, Josep M.; Turner, Alice M.; Han, MeiLan K.; Langhammer, Arnulf; Leivseth, Linda; Bakke, Per; Johannessen, Ane; Oga, Toru; Cosio, Borja; Ancochea-Bermúdez, Julio; Echazarreta, Andres; Roche, Nicolas; Burgel, Pierre-Régis; Sin, Don D.; Soriano, Joan B.; Puhan, Milo A.

    2018-01-01

    External validations and comparisons of prognostic models or scores are a prerequisite for their use in routine clinical care but are lacking in most medical fields including chronic obstructive pulmonary disease (COPD). Our aim was to externally validate and concurrently compare prognostic scores

  16. 78 FR 70598 - Submission for Review: Request for External Review (3206-NEW); Model Notice of Final Internal...

    Science.gov (United States)

    2013-11-26

    ... notice to enrollees about the result of any final internal adverse benefit determination, their external... OFFICE OF PERSONNEL MANAGEMENT Submission for Review: Request for External Review (3206-NEW); Model Notice of Final Internal Adverse Benefit Determination and Case Intake Form AGENCY: U.S. Office of...

  17. Interpreting biomarker data from the COPHES/DEMOCOPHES twin projects: Using external exposure data to understand biomarker differences among countries

    International Nuclear Information System (INIS)

    Smolders, R.; Den Hond, E.; Koppen, G.; Govarts, E.; Willems, H.; Casteleyn, L.; Kolossa-Gehring, M.; Fiddicke, U.; Castaño, A.; Koch, H.M.; Angerer, J.; Esteban, M.; Sepai, O.; Exley, K.; Bloemen, L.; Horvat, M.; Knudsen, L.E.; Joas, A.; Joas, R.; Biot, P.

    2015-01-01

    In 2011 and 2012, the COPHES/DEMOCOPHES twin projects performed the first ever harmonized human biomonitoring survey in 17 European countries. In more than 1800 mother–child pairs, individual lifestyle data were collected and cadmium, cotinine and certain phthalate metabolites were measured in urine. Total mercury was determined in hair samples. While the main goal of the COPHES/DEMOCOPHES twin projects was to develop and test harmonized protocols and procedures, the goal of the current paper is to investigate whether the observed differences in biomarker values among the countries implementing DEMOCOPHES can be interpreted using information from external databases on environmental quality and lifestyle. In general, 13 countries having implemented DEMOCOPHES provided high-quality data from external sources that were relevant for interpretation purposes. However, some data were not available for reporting or were not in line with predefined specifications. Therefore, only part of the external information could be included in the statistical analyses. Nonetheless, there was a highly significant correlation between national levels of fish consumption and mercury in hair, the strength of antismoking legislation was significantly related to urinary cotinine levels, and we were able to show indications that also urinary cadmium levels were associated with environmental quality and food quality. These results again show the potential of biomonitoring data to provide added value for (the evaluation of) evidence-informed policy making. - Highlights: • External data was collected to interpret HBM data from DEMOCOPHES. • Hg in hair could be related to fish consumption across different countries. • Urinary cotinine was related to strictness of anti-smoking legislation. • Urinary Cd was borderline significantly related to air and food quality. • Lack of comparable data among countries hampered the analysis

  18. Interpreting biomarker data from the COPHES/DEMOCOPHES twin projects: Using external exposure data to understand biomarker differences among countries

    Energy Technology Data Exchange (ETDEWEB)

    Smolders, R., E-mail: roel.smolders@vito.be [Flemish Institute of Technological Research (VITO), Environmental Risks and Health Unit, Boeretang 200, 2400 Mol (Belgium); Den Hond, E.; Koppen, G.; Govarts, E.; Willems, H. [Flemish Institute of Technological Research (VITO), Environmental Risks and Health Unit, Boeretang 200, 2400 Mol (Belgium); Casteleyn, L. [KU LEUVEN (Belgium); Kolossa-Gehring, M.; Fiddicke, U. [Federal Environment Agency (UBA) (Germany); Castaño, A. [Instituto de Salud Carlos III (Spain); Koch, H.M.; Angerer, J. [Institute for Prevention and Occupational Medicine of the German Social Accident Insurance - Institute of the Ruhr-Universität Bochum (IPA) (Germany); Esteban, M. [Instituto de Salud Carlos III (Spain); Sepai, O.; Exley, K. [Public Health England (United Kingdom); Bloemen, L. [Environmental Health Sciences International (Netherlands); Horvat, M. [Jožef Stefan Institute (Slovenia); Knudsen, L.E. [University of Copenhagen (Denmark); Joas, A.; Joas, R. [BiPRO (Germany); Biot, P. [FPS Health, Food Chain Safety and Environment (Belgium); and others

    2015-08-15

    In 2011 and 2012, the COPHES/DEMOCOPHES twin projects performed the first ever harmonized human biomonitoring survey in 17 European countries. In more than 1800 mother–child pairs, individual lifestyle data were collected and cadmium, cotinine and certain phthalate metabolites were measured in urine. Total mercury was determined in hair samples. While the main goal of the COPHES/DEMOCOPHES twin projects was to develop and test harmonized protocols and procedures, the goal of the current paper is to investigate whether the observed differences in biomarker values among the countries implementing DEMOCOPHES can be interpreted using information from external databases on environmental quality and lifestyle. In general, 13 countries having implemented DEMOCOPHES provided high-quality data from external sources that were relevant for interpretation purposes. However, some data were not available for reporting or were not in line with predefined specifications. Therefore, only part of the external information could be included in the statistical analyses. Nonetheless, there was a highly significant correlation between national levels of fish consumption and mercury in hair, the strength of antismoking legislation was significantly related to urinary cotinine levels, and we were able to show indications that also urinary cadmium levels were associated with environmental quality and food quality. These results again show the potential of biomonitoring data to provide added value for (the evaluation of) evidence-informed policy making. - Highlights: • External data was collected to interpret HBM data from DEMOCOPHES. • Hg in hair could be related to fish consumption across different countries. • Urinary cotinine was related to strictness of anti-smoking legislation. • Urinary Cd was borderline significantly related to air and food quality. • Lack of comparable data among countries hampered the analysis.

  19. A viscoelastic model of the correlation between respiratory lung tumour motion and an external abdominal signal

    International Nuclear Information System (INIS)

    Cavan, A.E.; Wilson, P.L.; Meyer, J.; Berbeco, R.I.

    2010-01-01

    Full text: Accuracy of radiotherapy treatment of lung cancer is limited by respiratory induced tumour motion. Compensation for this motion is required to increase treatment efficacy. The lung tumour motion is related to motion of an external abdominal marker, but a reliable model of this correlation is essential. Three viscoelastic systems were developed, in order to determine the best model and analyse its effectiveness on clinical data. Three 1D viscoelastic systems (a spring and dash pot in parallel, series and a combination) were developed and compared using a simulated breathing pattern. The most effective model was applied to 60 clinical data sets (consisting of co-ordinates of tumour and abdominal motion) from multiple treatment fractions of ten patients. The model was optimised for each data set, and efficacy determined by calculating the root mean square (RMS) error between the mo elled position and the actual tumour motion. Upon application to clinical data the parallel configuration achieved an average RMS error of 0.95 mm (superior-inferior direction). The model had patient specific parameters, and displayed good consistency over extended treatment periods. The model ha dled amplitude, frequency and baseline variations of the input signal, and phase shifts between tumour and abdominal motions. This study has shown that a viscoelastic model can be used to cor relate internal lung tumour motion with an external abdominal signal. The ability to handle breathing pattern in'egularities is comparable or better than previous models. Extending the model to a full 3D, pr dictive system could allow clinical implementation for radiotherapy.

  20. Collective modes of the Nambu--Jona-Lasinio model with an external U(1) gauge field

    International Nuclear Information System (INIS)

    Klevansky, S.P.; Jaenicke, J.; Lemmer, R.H.

    1991-01-01

    The effect of external color fields on the collective modes of the SU L (2)xSU R (2) chiral flavor version of the Nambu--Jona-Lasinio model is studied analytically in a U(1) approximation to the gauge fields. We show that the scalar and pseudoscalar modes respond differently to external chromomagnetic and -electric fields. In the former case, in which chiral asymmetry is enhanced, the modes remain well separated and vary slowly with the field, while in the latter case the scalar mode drops rapidly to become degenerate with the pseudoscalar mode in the chiral limit. In this regime, both modes are weakly coupled to quark matter, and the pseudoscalar pion mode in particular survives as a well-defined excitation as it enters the pair continuum. The Goldberger-Treiman relation, which is shown to hold in the presence of external fields, is responsible for this behavior. Chromoelectric and -magnetic polarizabilities are seen to be equal and opposite with absolute values β σ =2.0α s and β π =0.03α s for the scalar and pseudoscalar modes respectively

  1. Modelling of indoor exposure to nitrogen dioxide in the UK

    Science.gov (United States)

    Dimitroulopoulou, C.; Ashmore, M. R.; Byrne, M. A.; Kinnersley, R. P.

    A dynamic multi-compartment computer model has been developed to describe the physical processes determining indoor pollutant concentrations as a function of outdoor concentrations, indoor emission rates and building characteristics. The model has been parameterised for typical UK homes and workplaces and linked to a time-activity model to calculate exposures for a representative homemaker, schoolchild and office worker, with respect to NO 2. The estimates of population exposures, for selected urban and rural sites, are expressed in terms of annual means and frequency of hours in which air quality standards are exceeded. The annual mean exposures are estimated to fall within the range of 5-21 ppb for homes with no source, and 21-27 ppb for homes with gas cooking, varying across sites and population groups. The contribution of outdoor exposure to annual mean NO 2 exposure varied from 5 to 24%, that of indoor penetration of outdoor air from 17 to 86% and that of gas cooking from 0 to 78%. The frequency of exposure to 1 h mean concentrations above 150 ppb was very low, except for people cooking with gas.

  2. Rapid Optimization of External Quantum Efficiency of Thin Film Solar Cells Using Surrogate Modeling of Absorptivity.

    Science.gov (United States)

    Kaya, Mine; Hajimirza, Shima

    2018-05-25

    This paper uses surrogate modeling for very fast design of thin film solar cells with improved solar-to-electricity conversion efficiency. We demonstrate that the wavelength-specific optical absorptivity of a thin film multi-layered amorphous-silicon-based solar cell can be modeled accurately with Neural Networks and can be efficiently approximated as a function of cell geometry and wavelength. Consequently, the external quantum efficiency can be computed by averaging surrogate absorption and carrier recombination contributions over the entire irradiance spectrum in an efficient way. Using this framework, we optimize a multi-layer structure consisting of ITO front coating, metallic back-reflector and oxide layers for achieving maximum efficiency. Our required computation time for an entire model fitting and optimization is 5 to 20 times less than the best previous optimization results based on direct Finite Difference Time Domain (FDTD) simulations, therefore proving the value of surrogate modeling. The resulting optimization solution suggests at least 50% improvement in the external quantum efficiency compared to bare silicon, and 25% improvement compared to a random design.

  3. Separation of uncertainty and interindividual variability in human exposure modeling.

    NARCIS (Netherlands)

    Ragas, A.M.J.; Brouwer, F.P.E.; Buchner, F.L.; Hendriks, H.W.; Huijbregts, M.A.J.

    2009-01-01

    The NORMTOX model predicts the lifetime-averaged exposure to contaminants through multiple environmental media, that is, food, air, soil, drinking and surface water. The model was developed to test the coherence of Dutch environmental quality objectives (EQOs). A set of EQOs is called coherent if

  4. Mechanistic models for cancer development after short time radiation exposure

    International Nuclear Information System (INIS)

    Kottbauer, M. M.

    1997-12-01

    In this work two biological based models were developed. First the single-hit model for solid tumors (SHM-S) and second the single-hit model for leukemia (SHM-L). These models are a further development of the Armitage-Doll model for the special case of a short time radiation exposure. The basis of the models is the multistage process of carcinogeneses. The single-hit models provide simultaneously the age-dependent cancer-rate of spontaneous and radiation induced tumors as well as the dose-effect relationships at any age after exposure. The SHM-S leads to a biological based dose-effect relationship, which is similar to the relative risk model suggested by the ICRP 60. The SHM-S describes the increased mortality rate of the bomb survivors more accurate than the relative risk model. The SHM-L results in an additive dose-effect relationship. It is shown that only small differences in the derivation of the two models lead to the two dose-effect relationships. Beside the radiation exposure the new models consider the decrease of the cancer mortality rate at higher ages (age>75) which can be traced back mainly to three causes: competitive causes of death, reduction of cell proliferation and reduction of risk groups. The single-hit models also consider children cancer, the different rates of incidence and mortality, influence of the immune system and the cell-killing effect. (author)

  5. Extending Participatory Sensing to Personal Exposure Using Microscopic Land Use Regression Models

    Directory of Open Access Journals (Sweden)

    Luc Dekoninck

    2017-05-01

    Full Text Available Personal exposure is sensitive to the personal features and behavior of the individual, and including interpersonal variability will improve the health and quality of life evaluations. Participatory sensing assesses the spatial and temporal variability of environmental indicators and is used to quantify this interpersonal variability. Transferring the participatory sensing information to a specific study population is a basic requirement for epidemiological studies in the near future. We propose a methodology to reduce the void between participatory sensing and health research. Instantaneous microscopic land-use regression modeling (µLUR is an innovative approach. Data science techniques extract the activity-specific and route-sensitive spatiotemporal variability from the data. A data workflow to prepare and apply µLUR models to any mobile population is presented. The µLUR technique and data workflow are illustrated with models for exposure to traffic related Black Carbon. The example µLURs are available for three micro-environments; bicycle, in-vehicle, and indoor. Instantaneous noise assessments supply instantaneous traffic information to the µLURs. The activity specific models are combined into an instantaneous personal exposure model for Black Carbon. An independent external validation reached a correlation of 0.65. The µLURs can be applied to simulated behavioral patterns of individuals in epidemiological cohorts for advanced health and policy research.

  6. Intercomparison for individual monitoring of external exposure from photon radiation. Results of a co-ordinated research project 1996-1998

    International Nuclear Information System (INIS)

    1999-12-01

    This TECDOC presents the results of a Co-ordinated Research Project on Intercomparison for Individual Monitoring of External Exposure from photon radiation. The International Basic Safety Standards for Protection against Ionizing Radiation and for the Safety of Radiation Sources (BSS) have endorsed the use of the operational quantities for monitoring purposes. Specifically, personal dose equivalent, H p (d), is to be used for individual dosimetry to demonstrate compliance with the exposure limit recommendations, while for workplace area monitoring the ambient dose equivalent and the directional dose equivalent are recommended. In view of the technical difficulties associated with the introduction of these operational quantities the IAEA decided to assist Member States in their provision of appropriate dosimetry for occupational protection. In this respect, intercomparisons have proven to be a cost effective method of providing such support. A Co-ordinated Research Project (CRP) was started in 1997 on Intercomparison for Individual Monitoring of External Exposure from photon radiation, involving more than twenty laboratories from eastern Europe and the countries of the former Soviet Union, and focusing on personnel dosimetry services for nuclear power plants. This CRP was part of the activities of the IAEA Occupational Protection Programme, the objective4s of which are to promote and internationally harmonized approach for optimizing occupational radiation protection through: the development of guides, within the IAEA activities for establishing standards for radiation protection, for restricting radiation exposures in the workplace and for applying current occupational radiation protection techniques, and the promotion of the application of these guidelines. The preparatory phase included, in May 1997, a workshop aimed at familiarizing the participants with the new operational quantities

  7. Stoffenmanager exposure model: company-specific exposure assessments using a Bayesian methodology.

    NARCIS (Netherlands)

    Ven, P. van de; Fransman, W.; Schinkel, J.; Rubingh, C.; Warren, N.; Tielemans, E.

    2010-01-01

    The web-based tool "Stoffenmanager" was initially developed to assist small- and medium-sized enterprises in the Netherlands to make qualitative risk assessments and to provide advice on control at the workplace. The tool uses a mechanistic model to arrive at a "Stoffenmanager score" for exposure.

  8. The Life Cycle Evaluation Model of External Diseconomy of Open-loop Supply Chain

    Science.gov (United States)

    Liu, Qian; Hu, Tianjun

    2017-08-01

    In recent years, with the continuous deterioration of pollution, resource space is gradually narrowed, the number of waste items increased, people began to use the method of recycling on waste products to ease the pressure on the environment. This paper adopted the external diseconomy of open-loop supply chain as the research object and constructed the model by the life cycle evaluation method, comparative analysis through the case. This paper also concludes that the key to solving the problem is to realize the closed-loop supply chain and building reverse logistics system is of great significance.

  9. Theoretical modeling of the feedback stabilization of external MHD modes of toroidal geometry

    International Nuclear Information System (INIS)

    Chance, M.S.; Chu, M.S.; Okabayashi, M.

    2001-01-01

    A theoretical framework for understanding the feedback mechanism against external MHD modes has been formulated. Efficient computational tools - the GATO stability code coupled with a substantially modified VACUUM code - have been developed to effectively design viable feedback systems against these modes. The analysis assumed a thin resistive shell and a feedback coil structure accurately modeled in θ, with only a single harmonic variation in φ. An optimized configuration and placement of the feedback and sensor coils as well as the time constants and induced currents in the enclosing resistive shell have been computed for the DIII-D device. Up to 90% of the effectiveness of an ideal wall can be achieved. (author)

  10. ADHD and the externalizing spectrum: direct comparison of categorical, continuous, and hybrid models of liability in a nationally representative sample.

    Science.gov (United States)

    Carragher, Natacha; Krueger, Robert F; Eaton, Nicholas R; Markon, Kristian E; Keyes, Katherine M; Blanco, Carlos; Saha, Tulshi D; Hasin, Deborah S

    2014-08-01

    Alcohol use disorders, substance use disorders, and antisocial personality disorder share a common externalizing liability, which may also include attention-deficit hyperactivity disorder (ADHD). However, few studies have compared formal quantitative models of externalizing liability, with the aim of delineating the categorical and/or continuous nature of this liability in the community. This study compares categorical, continuous, and hybrid models of externalizing liability. Data were derived from the 2004-2005 National Epidemiologic Survey on Alcohol and Related Conditions (N = 34,653). Seven disorders were modeled: childhood ADHD and lifetime diagnoses of antisocial personality disorder (ASPD), nicotine dependence, alcohol dependence, marijuana dependence, cocaine dependence, and other substance dependence. The continuous latent trait model provided the best fit to the data. Measurement invariance analyses supported the fit of the model across genders, with females displaying a significantly lower probability of experiencing externalizing disorders. Cocaine dependence, marijuana dependence, other substance dependence, alcohol dependence, ASPD, nicotine dependence, and ADHD provided the greatest information, respectively, about the underlying externalizing continuum. Liability to externalizing disorders is continuous and dimensional in severity. The findings have important implications for the organizational structure of externalizing psychopathology in psychiatric nomenclatures.

  11. Modelling exposure of mammalian predators to anticoagulant rodenticide

    Directory of Open Access Journals (Sweden)

    Christopher John Topping

    2016-12-01

    Full Text Available Anticoagulant rodenticides (AR are a widespread and effective method of rodent control but there is concern about the impact these may have on non-target organisms, in particular secondary poisoning of rodent predators. Incidence and concentration of AR in free-living predators in Denmark is very high. We postulate that this is caused by widespread exposure due to widespread use of AR in Denmark in and around buildings. To investigate this theory a spatio-temporal model of AR use and mammalian predator distribution was created. This model was supported by data from an experimental study of mice as vectors of AR, and was used to evaluate likely impacts of restrictions imposed on AR use in Denmark banning the use of rodenticides for plant protection in woodlands and tree-crops. The model uses input based on frequencies and timings of baiting for rodent control for urban, rural and woodland locations and creates an exposure map based on spatio-temporal modelling of movement of mice-vectored AR (based on Apodemus flavicollis. Simulated predator territories are super-imposed over this exposure map to create an exposure index. Predictions from the model concur with field studies of AR prevalence both before and after the change in AR use. In most cases incidence of exposure to AR is predicted to be greater than 90%, although cessation of use in woodlots and Christmas tree plantations should reduce mean exposure concentrations. Model results suggest that the driver of high AR incidence in non-target small mammal predators is likely to be the pattern of use and not the distance AR is vectored. Reducing baiting frequency by 75% had different effects depending on the landscape simulated, but having a maximum of 12% reduction in exposure incidence, and in one landscape a maximum reduction of <2%. We discuss sources of uncertainty in the model and directions for future development of predictive models for environmental impact assessment of rodenticides. The

  12. Repeated exposure to high-frequency spanking and child externalizing behavior across the first decade: a moderating role for cumulative risk.

    Science.gov (United States)

    MacKenzie, Michael J; Nicklas, Eric; Brooks-Gunn, Jeanne; Waldfogel, Jane

    2014-12-01

    This study used the Fragile Families and Child Well-Being Study to examine the effects of repeated exposure to harsh parenting on child externalizing behavior across the first decade of life, and a moderating role for cumulative ecological risk. Maternal report of harsh parenting, defined as high frequency spanking, was assessed at age 1, 3, 5, and 9, along with child externalizing at age 9 (N=2,768). Controlling for gender, race, maternal nativity, and city of residence, we found a cumulative risk index to significantly moderate the effects of repeated harsh parenting on child behavior, with the effects of repeated high-frequency spanking being amplified for those experiencing greater levels of cumulative risk. Harsh parenting, in the form of high frequency spanking, remains a too common experience for children, and results demonstrate that the effects of repeated exposure to harsh parenting across the first decade are amplified for those children already facing the most burden. Copyright © 2014. Published by Elsevier Ltd.

  13. Study on Public Exposure and External Radiation Level at Gamma Green House and around MINT Dengkil Complex Boarder

    International Nuclear Information System (INIS)

    Faizal Azrin Abdul Razalim; Ismail Sulaiman; Khairuddin Mohamad Kontol; Ahmad Bazlie Abdul Kadir; Noor Fadilla Ismail; Hassan Sham; Ahmad Zainuri Mohd Dzomir

    2014-01-01

    This paper will discussing on the measurement of external radiation and the dose level which is acceptable to the public around the Gamma Green House and the border between Malaysian Nuclear Agency and housing project developed by Mah Sing Group. This research is made to verify the level of safety, especially for civilians residing in this area and to ensure compliance with the limit that has been set by the authorities, AELB (BSS/2010). Measurement method used in this research by using survey meter, TLD and OSL. (author)

  14. [Mediator processes in the brain structures in the late periods after external and combined exposure to ionizing radiation].

    Science.gov (United States)

    Taĭts, M Iu; Dudina, T V; Kandybo, T S; Elkina, A I

    1990-01-01

    In experiments with mature Wistar male rats it was shown that X-radiation of 12.9 mCi/kg and the combined effect of X-rays and 131I of 6.5 mCi/kg changed the rate of mediator processes in the structures responsible for the hypothalamic function regulation. At remote times (6 months) following irradiation differences were observed in the discoordination of mediator interrelations associated with the peculiarities of the indirect effect of external and combined irradiation implemented via endocrine mechanism system.

  15. Cleanup techniques for Finnish urban environments and external doses from 137Cs - modelling and calculations

    International Nuclear Information System (INIS)

    Moring, M.; Markkula, M.L.

    1997-03-01

    The external doses under various radioactive deposition conditions are assessed and the efficiencies of some simple decontamination techniques (grass cutting, vacuum sweeping, hosing of paved surfaces and roofs, and felling trees) are compared in the study. The present model has been constructed for the Finnish conditions and housing areas, using 137 Cs transfer data from the Nordic and Central European studies and models. The compartment model concerns behaviour and decontamination of 137 Cs in the urban environment under summer conditions. Doses to man have been calculated for wet (light rain) and dry deposition in four typical Finnish building areas: single-family wooden houses, brick terraced-houses, blocks of flats and urban office buildings. (26 refs.)

  16. An improved model for the reconstruction of past radon exposure.

    Science.gov (United States)

    Cauwels, P; Poffijn, A

    2000-05-01

    If the behavior of long-lived radon progeny was well understood, measurements of these could be used in epidemiological studies to estimate past radon exposure. Field measurements were done in a radon-prone area in the Ardennes (Belgium). The surface activity of several glass sheets was measured using detectors that were fixed on indoor glass surfaces. Simultaneously the indoor radon concentration was measured using diffusion chambers. By using Monte Carlo techniques, it could be proven that there is a discrepancy between this data set and the room model calculations, which are normally used to correlate surface activity and past radon exposure. To solve this, a modification of the model is proposed.

  17. Computation of External Quality Factors for RF Structures by Means of Model Order Reduction and a Perturbation Approach

    CERN Document Server

    Flisgen, Thomas; van Rienen, Ursula

    2016-01-01

    External quality factors are significant quantities to describe losses via waveguide ports in radio frequency resonators. The current contribution presents a novel approach to determine external quality factors by means of a two-step procedure: First, a state-space model for the lossless radio frequency structure is generated and its model order is reduced. Subsequently, a perturbation method is applied on the reduced model so that external losses are accounted for. The advantage of this approach results from the fact that the challenges in dealing with lossy systems are shifted to the reduced order model. This significantly saves computational costs. The present paper provides a short overview on existing methods to compute external quality factors. Then, the novel approach is introduced and validated in terms of accuracy and computational time by means of commercial software.

  18. Applied exposure modeling for residual radioactivity and release criteria

    International Nuclear Information System (INIS)

    Lee, D.W.

    1989-01-01

    The protection of public health and the environment from the release of materials with residual radioactivity for recycle or disposal as wastes without radioactive contents of concern presents a formidable challenge. Existing regulatory criteria are based on technical judgment concerning detectability and simple modeling. Recently, exposure modeling methodologies have been developed to provide a more consistent level of health protection. Release criteria derived from the application of exposure modeling methodologies share the same basic elements of analysis but are developed to serve a variety of purposes. Models for the support of regulations for all applications rely on conservative interpretations of generalized conditions while models developed to show compliance incorporate specific conditions not likely to be duplicated at other sites. Research models represent yet another type of modeling which strives to simulate the actual behavior of released material. In spite of these differing purposes, exposure modeling permits the application of sound and reasoned principles of radiation protection to the release of materials with residual levels of radioactivity. Examples of the similarities and differences of these models are presented and an application to the disposal of materials with residual levels of uranium contamination is discussed. 5 refs., 2 tabs

  19. A survey report for the biped locomotion model under external force

    International Nuclear Information System (INIS)

    Kato, Ichiro; Takanishi, Atsuo; Kume, Etsuo.

    1993-10-01

    A mechanical design study of biped locomotion robots is being performed at JAERI within the scope of the Human Acts Simulation Program (HASP). The design study at JAERI is of an arbitrarily mobile robot for inspection of nuclear facilities. We have developed the simulation software which has capability of obtaining several types of stable motions for straight walking in terms of design tools. In addition, we are studying more complex walking patterns such as turning. However, in order to realize the robustness of walking, it is also necessary for the robot to have a capability of walking under external force as a disturbance which is caused by touching an object and so on. A survey has been performed for collecting useful information from already existing biped locomotion robots. This is a survey report for the biped locomotion model under external force: the WL-12RIII/IV designed and developed at Waseda University. This report includes the machine model, control system, control method and results of walking experiments. (author)

  20. Quantum entanglement and criticality of the antiferromagnetic Heisenberg model in an external field

    International Nuclear Information System (INIS)

    Liu Guanghua; Li Ruoyan; Tian Guangshan

    2012-01-01

    By Lanczos exact diagonalization and the infinite time-evolving block decimation (iTEBD) technique, the two-site entanglement as well as the bipartite entanglement, the ground state energy, the nearest-neighbor correlations, and the magnetization in the antiferromagnetic Heisenberg (AFH) model under an external field are investigated. With increasing external field, the small size system shows some distinct upward magnetization stairsteps, accompanied synchronously with some downward two-site entanglement stairsteps. In the thermodynamic limit, the two-site entanglement, as well as the bipartite entanglement, the ground state energy, the nearest-neighbor correlations, and the magnetization are calculated, and the critical magnetic field h c = 2.0 is determined exactly. Our numerical results show that the quantum entanglement is sensitive to the subtle changing of the ground state, and can be used to describe the magnetization and quantum phase transition. Based on the discontinuous behavior of the first-order derivative of the entanglement entropy and fidelity per site, we think that the quantum phase transition in this model should belong to the second-order category. Furthermore, in the magnon existence region (h < 2.0), a logarithmically divergent behavior of block entanglement which can be described by a free bosonic field theory is observed, and the central charge c is determined to be 1. (paper)

  1. External circuit integration with electromagnetic particle in cell modeling of plasma focus devices

    International Nuclear Information System (INIS)

    Seng, Y. S.; Lee, P.; Rawat, R. S.

    2015-01-01

    The pinch performance of a plasma focus (PF) device is sensitive to the physical conditions of the breakdown phase. It is therefore essential to model and study the initial phase in order to optimize device performance. An external circuit is self consistently coupled to the electromagnetic particle in cell code to model the breakdown and initial lift phase of the United Nations University/International Centre for Theoretical Physics (UNU-ICTP) plasma focus device. Gas breakdown during the breakdown phase is simulated successfully, following a drop in the applied voltage across the device and a concurrent substantial rise in the circuit current. As a result, the plasma becomes magnetized, with the growing value of the magnetic field over time leading to the gradual lift off of the well formed current sheath into the axial acceleration phase. This lifting off, with simultaneous outward sheath motion along the anode and vertical cathode, and the strong magnetic fields in the current sheath region, was demonstrated in this work, and hence validates our method of coupling the external circuit to PF devices. Our method produces voltage waveforms that are qualitatively similar to the observed experimental voltage profiles of the UNU-ICTP device. Values of the mean electron energy before and after voltage breakdown turned out to be different, with the values after breakdown being much lower. In both cases, the electron energy density function turned out to be non-Maxwellian

  2. Chlorpyrifos PBPK/PD model for multiple routes of exposure.

    Science.gov (United States)

    Poet, Torka S; Timchalk, Charles; Hotchkiss, Jon A; Bartels, Michael J

    2014-10-01

    1. Chlorpyrifos (CPF) is an important pesticide used to control crop insects. Human Exposures to CPF will occur primarily through oral exposure to residues on foods. A physiologically based pharmacokinetic/pharmacodynamic (PBPK/PD) model has been developed that describes the relationship between oral, dermal and inhalation doses of CPF and key events in the pathway for cholinergic effects. The model was built on a prior oral model that addressed age-related changes in metabolism and physiology. This multi-route model was developed in rats and humans to validate all scenarios in a parallelogram design. 2. Critical biological effects from CPF exposure require metabolic activation to CPF oxon, and small amounts of metabolism in tissues will potentially have a great effect on pharmacokinetics and pharmacodynamic outcomes. Metabolism (bioactivation and detoxification) was therefore added in diaphragm, brain, lung and skin compartments. Pharmacokinetic data are available for controlled human exposures via the oral and dermal routes and from oral and inhalation studies in rats. The validated model was then used to determine relative dermal versus inhalation uptake from human volunteers exposed to CPF in an indoor scenario.

  3. Tropically driven and externally forced patterns of Antarctic sea ice change: reconciling observed and modeled trends

    Science.gov (United States)

    Schneider, David P.; Deser, Clara

    2017-09-01

    Recent work suggests that natural variability has played a significant role in the increase of Antarctic sea ice extent during 1979-2013. The ice extent has responded strongly to atmospheric circulation changes, including a deepened Amundsen Sea Low (ASL), which in part has been driven by tropical variability. Nonetheless, this increase has occurred in the context of externally forced climate change, and it has been difficult to reconcile observed and modeled Antarctic sea ice trends. To understand observed-model disparities, this work defines the internally driven and radiatively forced patterns of Antarctic sea ice change and exposes potential model biases using results from two sets of historical experiments of a coupled climate model compared with observations. One ensemble is constrained only by external factors such as greenhouse gases and stratospheric ozone, while the other explicitly accounts for the influence of tropical variability by specifying observed SST anomalies in the eastern tropical Pacific. The latter experiment reproduces the deepening of the ASL, which drives an increase in regional ice extent due to enhanced ice motion and sea surface cooling. However, the overall sea ice trend in every ensemble member of both experiments is characterized by ice loss and is dominated by the forced pattern, as given by the ensemble-mean of the first experiment. This pervasive ice loss is associated with a strong warming of the ocean mixed layer, suggesting that the ocean model does not locally store or export anomalous heat efficiently enough to maintain a surface environment conducive to sea ice expansion. The pervasive upper-ocean warming, not seen in observations, likely reflects ocean mean-state biases.

  4. Tropically driven and externally forced patterns of Antarctic sea ice change: reconciling observed and modeled trends

    Science.gov (United States)

    Schneider, David P.; Deser, Clara

    2018-06-01

    Recent work suggests that natural variability has played a significant role in the increase of Antarctic sea ice extent during 1979-2013. The ice extent has responded strongly to atmospheric circulation changes, including a deepened Amundsen Sea Low (ASL), which in part has been driven by tropical variability. Nonetheless, this increase has occurred in the context of externally forced climate change, and it has been difficult to reconcile observed and modeled Antarctic sea ice trends. To understand observed-model disparities, this work defines the internally driven and radiatively forced patterns of Antarctic sea ice change and exposes potential model biases using results from two sets of historical experiments of a coupled climate model compared with observations. One ensemble is constrained only by external factors such as greenhouse gases and stratospheric ozone, while the other explicitly accounts for the influence of tropical variability by specifying observed SST anomalies in the eastern tropical Pacific. The latter experiment reproduces the deepening of the ASL, which drives an increase in regional ice extent due to enhanced ice motion and sea surface cooling. However, the overall sea ice trend in every ensemble member of both experiments is characterized by ice loss and is dominated by the forced pattern, as given by the ensemble-mean of the first experiment. This pervasive ice loss is associated with a strong warming of the ocean mixed layer, suggesting that the ocean model does not locally store or export anomalous heat efficiently enough to maintain a surface environment conducive to sea ice expansion. The pervasive upper-ocean warming, not seen in observations, likely reflects ocean mean-state biases.

  5. Derivation and External Validation of Prediction Models for Advanced Chronic Kidney Disease Following Acute Kidney Injury.

    Science.gov (United States)

    James, Matthew T; Pannu, Neesh; Hemmelgarn, Brenda R; Austin, Peter C; Tan, Zhi; McArthur, Eric; Manns, Braden J; Tonelli, Marcello; Wald, Ron; Quinn, Robert R; Ravani, Pietro; Garg, Amit X

    2017-11-14

    Some patients will develop chronic kidney disease after a hospitalization with acute kidney injury; however, no risk-prediction tools have been developed to identify high-risk patients requiring follow-up. To derive and validate predictive models for progression of acute kidney injury to advanced chronic kidney disease. Data from 2 population-based cohorts of patients with a prehospitalization estimated glomerular filtration rate (eGFR) of more than 45 mL/min/1.73 m2 and who had survived hospitalization with acute kidney injury (defined by a serum creatinine increase during hospitalization > 0.3 mg/dL or > 50% of their prehospitalization baseline), were used to derive and validate multivariable prediction models. The risk models were derived from 9973 patients hospitalized in Alberta, Canada (April 2004-March 2014, with follow-up to March 2015). The risk models were externally validated with data from a cohort of 2761 patients hospitalized in Ontario, Canada (June 2004-March 2012, with follow-up to March 2013). Demographic, laboratory, and comorbidity variables measured prior to discharge. Advanced chronic kidney disease was defined by a sustained reduction in eGFR less than 30 mL/min/1.73 m2 for at least 3 months during the year after discharge. All participants were followed up for up to 1 year. The participants (mean [SD] age, 66 [15] years in the derivation and internal validation cohorts and 69 [11] years in the external validation cohort; 40%-43% women per cohort) had a mean (SD) baseline serum creatinine level of 1.0 (0.2) mg/dL and more than 20% had stage 2 or 3 acute kidney injury. Advanced chronic kidney disease developed in 408 (2.7%) of 9973 patients in the derivation cohort and 62 (2.2%) of 2761 patients in the external validation cohort. In the derivation cohort, 6 variables were independently associated with the outcome: older age, female sex, higher baseline serum creatinine value, albuminuria, greater severity of acute kidney injury, and higher

  6. A model of the response of GMR of metallic multilayers to external magnetic field

    Directory of Open Access Journals (Sweden)

    Uba J.I.

    2015-12-01

    Full Text Available It has not been possible to transform resistivity models in terms of magnetic field in order to account for variation of giant magnetoresistance (GMR with external magnetic field, which would have led to determination of material properties. This problem is approached mathematically via variation calculus to arrive at an exponential function that fits observed GMR values. Using this model in free electron approximation, the mean Fermi vector, susceptibility and total density of states of a number of metallic multilayers are determined from their reported GMR values. Susceptibility is found to depend on interface roughness and antiferromagnetic (AF coupling; thus, it gives qualitative measure of interface quality and AF coupling. Comparison of susceptibilities and GMRs of electrodeposited and ion beam sputtered Co/Cu structures shows that a rough interface suppresses GMR in the former but enhances it in the latter.

  7. Thermal Performance of the LHC External Auxiliary Bus-Bar Tube Mathematical Modelling

    CERN Document Server

    Kowalczyk, P; Sacré, P; Skoczen, Blazej

    1998-01-01

    The Large Hadron Collider (LHC) externally routed auxiliary bus-bar tube (EAB) will house the electrical feeders of the LHC short straight section (SSS) correcting magnets. The superconducting wires w ill be contained in a stainless steel tube and immersed in a quasi-static helium bath. The EAB thermal performance during the cooling of the magnets down to the operating temperature of 1.9 K is studi ed. A 3-d finite element thermal model of the EAB during a cooling process from 293 K to 4.5 K is described. The semi-analytical model of the EAB cool-down from 4.5 K to 1.9 K is also presented.

  8. Assessment of health-cost externalities of air pollution at the national level using the EVA model system

    Energy Technology Data Exchange (ETDEWEB)

    Brandt, J.; Silver, J.D.; Frohn, L.M. (and others)

    2011-07-15

    Air pollution has significant negative impacts on human health and well-being, which entail substantial economic consequences. We have developed an integrated model system, EVA (External Valuation of Air pollution; Frohn et al., 2005; Andersen et al., 2007; Brandt et al., 2010), to assess health-related economic externalities of air pollution resulting from specific emission sources or sectors. The EVA system was initially developed to assess externalities from power production, but in this study it is extended to evaluate costs at the national level from all major emission sectors. In this study, we estimate the impacts and total externality costs from the main emission sectors in Denmark, representing the 10 major SNAP codes. Furthermore, we assess the impacts and externality costs of all emissions simultaneously from the whole of Europe as well as from international ship traffic in general, since this sector seems to be very important but is currently unregulated. (Author)

  9. PBTK modeling demonstrates contribution of dermal and inhalation exposure components to end-exhaled breath concentrations of naphthalene.

    Science.gov (United States)

    Kim, David; Andersen, Melvin E; Chao, Yi-Chun E; Egeghy, Peter P; Rappaport, Stephen M; Nylander-French, Leena A

    2007-06-01

    Dermal and inhalation exposure to jet propulsion fuel 8 (JP-8) have been measured in a few occupational exposure studies. However, a quantitative understanding of the relationship between external exposures and end-exhaled air concentrations has not been described for occupational and environmental exposure scenarios. Our goal was to construct a physiologically based toxicokinetic (PBTK) model that quantitatively describes the relative contribution of dermal and inhalation exposures to the end-exhaled air concentrations of naphthalene among U.S. Air Force personnel. The PBTK model comprised five compartments representing the stratum corneum, viable epidermis, blood, fat, and other tissues. The parameters were optimized using exclusively human exposure and biological monitoring data. The optimized values of parameters for naphthalene were a) permeability coefficient for the stratum corneum 6.8 x 10(-5) cm/hr, b) permeability coefficient for the viable epidermis 3.0 x 10(-3) cm/hr, c) fat:blood partition coefficient 25.6, and d) other tissue:blood partition coefficient 5.2. The skin permeability coefficient was comparable to the values estimated from in vitro studies. Based on simulations of workers' exposures to JP-8 during aircraft fuel-cell maintenance operations, the median relative contribution of dermal exposure to the end-exhaled breath concentration of naphthalene was 4% (10th percentile 1% and 90th percentile 11%). PBTK modeling allowed contributions of the end-exhaled air concentration of naphthalene to be partitioned between dermal and inhalation routes of exposure. Further study of inter- and intraindividual variations in exposure assessment is required to better characterize the toxicokinetic behavior of JP-8 components after occupational and/or environmental exposures.

  10. Sex Differences in Adolescent Depression: Stress Exposure and Reactivity Models

    Science.gov (United States)

    Hankin, Benjamin L.; Mermelstein, Robin; Roesch, Linda

    2007-01-01

    Stress exposure and reactivity models were examined as explanations for why girls exhibit greater levels of depressive symptoms than boys. In a multiwave, longitudinal design, adolescents' depressive symptoms, alcohol usage, and occurrence of stressors were assessed at baseline, 6, and 12 months later (N=538; 54.5% female; ages 13-18, average…

  11. Task-based dermal exposure models for regulatory risk assessment

    NARCIS (Netherlands)

    Warren, N.D.; Marquart, H.; Christopher, Y.; Laitinen, J.; Hemmen, J.J. van

    2006-01-01

    The regulatory risk assessment of chemicals requires the estimation of occupational dermal exposure. Until recently, the models used were either based on limited data or were specific to a particular class of chemical or application. The EU project RISKOFDERM has gathered a considerable number of

  12. Population-based nutrikinetic modeling of polyphenol exposure

    NARCIS (Netherlands)

    van Velzen, E.J.J.; Westerhuis, J.A.; Grün, C.H.; Jacobs, D.M.; Eilers, P.H.C.; Mulder, Th.P.; Foltz, M.; Garczarek, U.; Kemperman, R.; Vaughan, E. E.; van Duynhoven, J.P.M.; Smilde, A.K.

    2014-01-01

    The beneficial health effects of fruits and vegetables have been attributed to their polyphenol content. These compounds undergo many bioconversions in the body. Modeling polyphenol exposure of humans upon intake is a prerequisite for understanding the modulating effect of the food matrix and the

  13. Population-based nutrikinetic modelling of phytochemical exposure

    NARCIS (Netherlands)

    Velzen, van E.J.J.; Westerhuis, J.A.; Grün, C.H.; Duynhoven, van J.P.M.; Jacobs, D.M.; Eilers, P.H.C.; Mulder, T.P.; Foltz, M.; Garczarek, U.; Kemperman, R.; Vaughan, E.E.; Smilde, A.K.

    2014-01-01

    The beneficial health effects of fruits and vegetables have been attributed to their polyphenol content. These compounds undergo many bioconversions in the body. Modeling polyphenol exposure of humans upon intake is a prerequisite for understanding the modulating effect of the food matrix and the

  14. Population models for time-varying pesticide exposure

    NARCIS (Netherlands)

    Jager T; Jong FMW de; Traas TP; LER; SEC

    2007-01-01

    A model has recently been developed at RIVM to predict the effects of variable exposure to pesticides of plant and animal populations in surface water. Before a pesticide is placed on the market, the environmental risk of the substance has to be assessed. This risk is estimated by comparing

  15. Parameterization models for pesticide exposure via crop consumption.

    Science.gov (United States)

    Fantke, Peter; Wieland, Peter; Juraske, Ronnie; Shaddick, Gavin; Itoiz, Eva Sevigné; Friedrich, Rainer; Jolliet, Olivier

    2012-12-04

    An approach for estimating human exposure to pesticides via consumption of six important food crops is presented that can be used to extend multimedia models applied in health risk and life cycle impact assessment. We first assessed the variation of model output (pesticide residues per kg applied) as a function of model input variables (substance, crop, and environmental properties) including their possible correlations using matrix algebra. We identified five key parameters responsible for between 80% and 93% of the variation in pesticide residues, namely time between substance application and crop harvest, degradation half-lives in crops and on crop surfaces, overall residence times in soil, and substance molecular weight. Partition coefficients also play an important role for fruit trees and tomato (Kow), potato (Koc), and lettuce (Kaw, Kow). Focusing on these parameters, we develop crop-specific models by parametrizing a complex fate and exposure assessment framework. The parametric models thereby reflect the framework's physical and chemical mechanisms and predict pesticide residues in harvest using linear combinations of crop, crop surface, and soil compartments. Parametric model results correspond well with results from the complex framework for 1540 substance-crop combinations with total deviations between a factor 4 (potato) and a factor 66 (lettuce). Predicted residues also correspond well with experimental data previously used to evaluate the complex framework. Pesticide mass in harvest can finally be combined with reduction factors accounting for food processing to estimate human exposure from crop consumption. All parametric models can be easily implemented into existing assessment frameworks.

  16. The assumption of heterogeneous or homogeneous radioactive contamination in soil/sediment: does it matter in terms of the external exposure of fauna?

    International Nuclear Information System (INIS)

    Beaugelin-Seiller, K.

    2014-01-01

    The classical approach to environmental radioprotection is based on the assumption of homogeneously contaminated media. However, in soils and sediments there may be a significant variation of radioactivity with depth. The effect of this heterogeneity was investigated by examining the external exposure of various sediment and soil organisms, and determining the resulting dose rates, assuming a realistic combination of locations and radionuclides. The results were dependent on the exposure situation, i.e., the organism, its location, and the quality and quantity of radionuclides. The dose rates ranged over three orders of magnitude. The assumption of homogeneous contamination was not consistently conservative (if associated with a level of radioactivity averaged over the full thickness of soil or sediment that was sampled). Dose assessment for screening purposes requires consideration of the highest activity concentration measured in a soil/sediment that is considered to be homogeneously contaminated. A more refined assessment (e.g., higher tier of a graded approach) should take into consideration a more realistic contamination profile, and apply different dosimetric approaches. - Highlights: • Defining contamination as homogeneous may not be conservative for dose assessment. • The impact of source heterogeneity on dose is closely linked to the exposure scenario. • Dosimetric calculations (method and tool) should differ from screening to higher tiers

  17. Ionizing radiations and their impact on basic functions of the genital system on the women (external exposure)

    International Nuclear Information System (INIS)

    Marinova, G.

    1976-01-01

    Data were summarized from dispensary polyclinic follow-up records over the period September 1969 through 1975 for 400 female X-ray personnel and 90 control employees free of occupational radiation exposure. In 80% of subjects in the survey group, first employment in radiation work was at less than 30 years of age. Exposure rates, as estimated from dosimetry film records, ranged from 20 to 100 mR/month, and integrated doses in no case exceeded the permissible annual levels over the past 5 years. The proportion of subjects presenting with menstrual disturbances was 42% for radiation workers versus 7.7% for controls. Distribution by types of disorders was as follows: oligomenorrhea, 35%; hypermenorrhea, 29%; irregular cycles, 15%; secondary amenorrhea, 9%; and dysmenorrhea associated with oligo- or hypermenorrhea, 22%. In 30 subjects with menstrual disturbances developing during the follow-up period, examinations included vaginal microbiology, cyclic vaginal cytodiagnostics, and pregnandiol levels. Immunoserologic assays were conducted in a total of 275 subjects, with or without menstrual disturbances, who were matched to allow comparison of results. Cytogenetic analysis of peripheral blood lymphocytes in 30 subjects with menstrual disturbances indicated radiation-induced chromosome aberrations to be present in 17 cases. Benign tumors and cancer of genital organs were diagnosed in 7.5 and 8.0%, respectively, of radiation workers as compared with 10.0 and 0.0%, respectively, in controls. All of the 66 pregnancies observed ended at term with delivery of live, apparently normal, progeny and an uneventful placental period. Gross and microscopic examination of 20 placentas and 30 chorions from artificially interrupted pregnancies disclosed no pathologic alterations. For the total of subjects under dispensary observation, there was a high rate of abortions by request. In conclusion, occupational radiation exposure, even where well below the maximum permissible level, does

  18. Review and evaluation of performance measures for survival prediction models in external validation settings

    Directory of Open Access Journals (Sweden)

    M. Shafiqur Rahman

    2017-04-01

    Full Text Available Abstract Background When developing a prediction model for survival data it is essential to validate its performance in external validation settings using appropriate performance measures. Although a number of such measures have been proposed, there is only limited guidance regarding their use in the context of model validation. This paper reviewed and evaluated a wide range of performance measures to provide some guidelines for their use in practice. Methods An extensive simulation study based on two clinical datasets was conducted to investigate the performance of the measures in external validation settings. Measures were selected from categories that assess the overall performance, discrimination and calibration of a survival prediction model. Some of these have been modified to allow their use with validation data, and a case study is provided to describe how these measures can be estimated in practice. The measures were evaluated with respect to their robustness to censoring and ease of interpretation. All measures are implemented, or are straightforward to implement, in statistical software. Results Most of the performance measures were reasonably robust to moderate levels of censoring. One exception was Harrell’s concordance measure which tended to increase as censoring increased. Conclusions We recommend that Uno’s concordance measure is used to quantify concordance when there are moderate levels of censoring. Alternatively, Gönen and Heller’s measure could be considered, especially if censoring is very high, but we suggest that the prediction model is re-calibrated first. We also recommend that Royston’s D is routinely reported to assess discrimination since it has an appealing interpretation. The calibration slope is useful for both internal and external validation settings and recommended to report routinely. Our recommendation would be to use any of the predictive accuracy measures and provide the corresponding predictive

  19. The calculation of dose from external photon exposures using reference human phantoms and Monte-Carlo methods. Pt. 1

    International Nuclear Information System (INIS)

    Kramer, R.; Zankl, M.; Williams, G.; Drexler, G.

    1982-12-01

    By the help of a Monte-Carlo program the dose that single organs, organ groups and bigger or smaller parts of body would receive on an average, caused by an irradiation definitely fixed by the geometry of irradiation and photon energy, can be determined. Thus the phantom in connection with the Monte-Carlo program can be used for several considerations as for example - calculation of dose from occupational exposures - calculation of dose from diagnostic procedures - calculation of dose from radiotherapy procedures. (orig.)

  20. Measurement of the external doses at low and high exposures by Agfa personal monitoring film, FD-III-B badge

    International Nuclear Information System (INIS)

    Mihai, F.; Stochioiu, A.; Bercea, S.; Udup, E.; Tudor, I.

    2008-01-01

    Full text: A growing number of papers report occupational exposure monitoring by different dosemeter devices. Researches into improvement of the personal dosemeter systems are encouraged. Dose measurement and especially skin dose measurement, are therefore increasingly important. Methods and acceptable dosemeter are not clearly defined and differ from a dosimetry laboratory to other depending on their specifically work procedure and type of dosemeter utilized. Taking into account the characteristic of the work place (industry, research, medical application) dosemeter have to cover a large dose range. The dose assessment problems are manly in low doses range (under 0.2 mSv) and higher doses range. For example, typical for radiation oncology and nuclear accident dosimetry the dose ranges are on the order of 2-70 Gy and 0.1-5 Gy. This work presents the performance of the Agfa personal monitoring film, badge FD-III-B type used in the most of the occupational exposure monitoring from Romania. The FD-III-B dosimeter, manufactured in Romania, is used for monitoring personnel working in radioactive environment - the photodosimetric method is the one of the most reliable method presenting the advantage that the film may be considered as master probe over 30 year and may be utilized during litigation. The dosimeter contains metallic filters of Al, Cu, Pb with different thicknesses, a plastic filter and a open window. The badge FD-III-B is a class B dosimeter according to the dose range and an indices 3 dosimeter from energy range of the radiations in conformity with Romanian Standard in force. Film Agfa 'personal monitoring', tacked in this experiment, consists of a low speed film (D2) and a very sensitive film (D10) designed for recording X-ray, gamma and beta radiation over the doses range 0.1 mSv to 1 Sv. The experiments have been effectuated at different background optical density (base fog) of the films and at different sources of radiation: 13 :7Cs, 60 Co and 24 : 1 Am

  1. Multicentre external validation of the BIMC model for solid solitary pulmonary nodule malignancy prediction

    Energy Technology Data Exchange (ETDEWEB)

    Soardi, Gian Alberto; Perandini, Simone; Motton, Massimiliano; Montemezzi, Stefania [AOUI Verona, UOC Radiologia, Ospedale Maggiore di Borgo Trento, Verona (Italy); Larici, Anna Rita; Del Ciello, Annemilia [Universita Cattolica del Sacro Cuore, Dipartimento di Scienze Radiologiche, Roma (Italy); Rizzardi, Giovanna [UO Chirurgia Toracica, Ospedale Humanitas Gavazzeni, Bergamo (Italy); Solazzo, Antonio [UO Radiologia, Ospedale Humanitas Gavazzeni, Bergamo (Italy); Mancino, Laura [UO Pneumologia, Ospedale dell' Angelo di Mestre, Mestre (Italy); Bernhart, Marco [UO Radiologia, Ospedale dell' Angelo di Mestre, Mestre (Italy)

    2017-05-15

    To provide multicentre external validation of the Bayesian Inference Malignancy Calculator (BIMC) model by assessing diagnostic accuracy in a cohort of solitary pulmonary nodules (SPNs) collected in a clinic-based setting. To assess model impact on SPN decision analysis and to compare findings with those obtained via the Mayo Clinic model. Clinical and imaging data were retrospectively collected from 200 patients from three centres. Accuracy was assessed by means of receiver-operating characteristic (ROC) areas under the curve (AUCs). Decision analysis was performed by adopting both the American College of Chest Physicians (ACCP) and the British Thoracic Society (BTS) risk thresholds. ROC analysis showed an AUC of 0.880 (95 % CI, 0.832-0.928) for the BIMC model and of 0.604 (95 % CI, 0.524-0.683) for the Mayo Clinic model. Difference was 0.276 (95 % CI, 0.190-0.363, P < 0.0001). Decision analysis showed a slightly reduced number of false-negative and false-positive results when using ACCP risk thresholds. The BIMC model proved to be an accurate tool when characterising SPNs. In a clinical setting it can distinguish malignancies from benign nodules with minimal errors by adopting current ACCP or BTS risk thresholds and guiding lesion-tailored diagnostic and interventional procedures during the work-up. (orig.)

  2. Exposure to Engineered Nanomaterial Results in Disruption of Brush Borders in Epithelia Models in vitro

    Science.gov (United States)

    Faust, James J.

    Engineered nanoparticles (NP; 10-9 m) have found use in a variety of consumer goods and medical devices because of the unique changes in material properties that occur when synthesized on the nanoscale. Although many definitions for nanoparticle exist, from the perspective of size, nanoparticle is defined as particles with diameters less than 100 nm in any external dimension. Examples of their use include titanium dioxide added as a pigment in products intended to be ingested by humans, silicon dioxide NPs are used in foods as an anticaking agent, and gold or iron oxide NPs can be used as vectors for drug delivery or contrast agents for specialized medical imaging. Although the intended use of these NPs is often to improve human health, it has come to the attention of investigators that NPs can have unintended or even detrimental effects on the organism. This work describes one such unintended effect of NP exposure from the perspective of exposure via the oral route. First, this Dissertation will explain an event referred to as brush border disruption that occurred after nanoparticles interacted with an in vitro model of the human intestinal epithelium. Second, this Dissertation will identify and characterize several consumer goods that were shown to contain titanium dioxide that are intended to be ingested. Third, this Dissertation shows that sedimentation due to gravity does not artifactually result in disruption of brush borders as a consequence of exposure to food grade titanium dioxide in vitro. Finally, this Dissertation will demonstrate that iron oxide nanoparticles elicited similar effects after exposure to an in vitro brush border expressing model of the human placenta. Together, these data suggest that brush border disruption is not an artifact of the material/cell culture model, but instead represents a bona fide biological response as a result of exposure to nanomaterial.

  3. Exposure to traffic pollution: comparison between measurements and a model.

    Science.gov (United States)

    Alili, F; Momas, I; Callais, F; Le Moullec, Y; Sacre, C; Chiron, M; Flori, J P

    2001-01-01

    French researchers from the Building Scientific and Technical Center have produced a traffic-exposure index. To achieve this, they used an air pollution dispersion model that enabled them to calculate automobile pollutant concentrations in front of subjects' residences and places of work. Researchers used this model, which was tested at 27 Paris canyon street sites, and compared nitrogen oxides measurements obtained with passive samplers during a 6-wk period and calculations derived from the model. There was a highly significant correlation (r = .83) between the 2 series of values; their mean concentrations were not significantly different. The results suggested that the aforementioned model could be a useful epidemiological tool for the classification of city dwellers by present-or even cumulative exposure to automobile air pollution.

  4. Streamwise-body-force-model for rapid simulation combining internal and external flow fields

    Directory of Open Access Journals (Sweden)

    Cui Rong

    2016-10-01

    Full Text Available A streamwise-body-force-model (SBFM is developed and applied in the overall flow simulation for the distributed propulsion system, combining internal and external flow fields. In view of axial stage effects, fan or compressor effects could be simplified as body forces along the streamline. These body forces which are functions of local parameters could be added as source terms in Navier-Stokes equations to replace solid boundary conditions of blades and hubs. The validation of SBFM with uniform inlet and distortion inlet of compressors shows that pressure performance characteristics agree well with experimental data. A three-dimensional simulation of the integration configuration, via a blended wing body aircraft with a distributed propulsion system using the SBFM, has been completed. Lift coefficient and drag coefficient agree well with wind tunnel test results. Results show that to reach the goal of rapid integrated simulation combining internal and external flow fields, the computational fluid dynamics method based on SBFM is reasonable.

  5. The negative binomial distribution as a model for external corrosion defect counts in buried pipelines

    International Nuclear Information System (INIS)

    Valor, Alma; Alfonso, Lester; Caleyo, Francisco; Vidal, Julio; Perez-Baruch, Eloy; Hallen, José M.

    2015-01-01

    Highlights: • Observed external-corrosion defects in underground pipelines revealed a tendency to cluster. • The Poisson distribution is unable to fit extensive count data for these type of defects. • In contrast, the negative binomial distribution provides a suitable count model for them. • Two spatial stochastic processes lead to the negative binomial distribution for defect counts. • They are the Gamma-Poisson mixed process and the compound Poisson process. • A Rogeŕs process also arises as a plausible temporal stochastic process leading to corrosion defect clustering and to negative binomially distributed defect counts. - Abstract: The spatial distribution of external corrosion defects in buried pipelines is usually described as a Poisson process, which leads to corrosion defects being randomly distributed along the pipeline. However, in real operating conditions, the spatial distribution of defects considerably departs from Poisson statistics due to the aggregation of defects in groups or clusters. In this work, the statistical analysis of real corrosion data from underground pipelines operating in southern Mexico leads to conclude that the negative binomial distribution provides a better description for defect counts. The origin of this distribution from several processes is discussed. The analysed processes are: mixed Gamma-Poisson, compound Poisson and Roger’s processes. The physical reasons behind them are discussed for the specific case of soil corrosion.

  6. Kinetic Ising model in a time-dependent oscillating external magnetic field: effective-field theory

    International Nuclear Information System (INIS)

    Deviren, Bayram; Canko, Osman; Keskin, Mustafa

    2010-01-01

    Recently, Shi et al. [2008 Phys. Lett. A 372 5922] have studied the dynamical response of the kinetic Ising model in the presence of a sinusoidal oscillating field and presented the dynamic phase diagrams by using an effective-field theory (EFT) and a mean-field theory (MFT). The MFT results are in conflict with those of the earlier work of Tomé and de Oliveira, [1990 Phys. Rev. A 41 4251]. We calculate the dynamic phase diagrams and find that our results are similar to those of the earlier work of Tomé and de Oliveira; hence the dynamic phase diagrams calculated by Shi et al. are incomplete within both theories, except the low values of frequencies for the MFT calculation. We also investigate the influence of external field frequency (ω) and static external field amplitude (h 0 ) for both MFT and EFT calculations. We find that the behaviour of the system strongly depends on the values of ω and h 0 . (general)

  7. Regional Externalities

    NARCIS (Netherlands)

    Heijman, W.J.M.

    2007-01-01

    The book offers practical and theoretical insights in regional externalities. Regional externalities are a specific subset of externalities that can be defined as externalities where space plays a dominant role. This class of externalities can be divided into three categories: (1) externalities

  8. A dermal model for spray painters, part I : subjective exposure modelling of spray paint deposition

    NARCIS (Netherlands)

    Brouwer, D.H.; Semple, S.; Marquart, J.; Cherrie, J.W.

    2001-01-01

    The discriminative power of existing dermal exposure models is limited. Most models only allow occupational hygienists to rank workers between and within workplaces according to broad bands of dermal exposure. No allowance is made for the work practices of different individuals. In this study a

  9. Advanced Mechanistic 3D Spatial Modeling and Analysis Methods to Accurately Represent Nuclear Facility External Event Scenarios

    Energy Technology Data Exchange (ETDEWEB)

    Sezen, Halil [The Ohio State Univ., Columbus, OH (United States). Dept. of Civil, Environmental and Geodetic Engineering; Aldemir, Tunc [The Ohio State Univ., Columbus, OH (United States). College of Engineering, Nuclear Engineering Program, Dept. of Mechanical and Aerospace Engineering; Denning, R. [The Ohio State Univ., Columbus, OH (United States); Vaidya, N. [Rizzo Associates, Pittsburgh, PA (United States)

    2017-12-29

    Probabilistic risk assessment of nuclear power plants initially focused on events initiated by internal faults at the plant, rather than external hazards including earthquakes and flooding. Although the importance of external hazards risk analysis is now well recognized, the methods for analyzing low probability external hazards rely heavily on subjective judgment of specialists, often resulting in substantial conservatism. This research developed a framework to integrate the risk of seismic and flooding events using realistic structural models and simulation of response of nuclear structures. The results of four application case studies are presented.

  10. Personnel Dosimetry for Radiation Accidents. Proceedings of a Symposium on Personnel Dosimetry for Accidental High-Level Exposure to External and Internal Radiation

    International Nuclear Information System (INIS)

    1965-01-01

    Accidents involving the exposure of persons to high levels of radiation have been few in number and meticulous precautions are taken in an effort to maintain this good record. When, however, such an accident does occur, a timely estimate of the dose received can be of considerable help to the physician in deciding whether a particular person requires medical treatment, and in selecting the most appropriate treatment. Individual dosimetry provides the physical basis for relating the observed effects to those in other accident cases, to other human data, and to data from animal experiments, thus providing an important aid to rational treatment and to the accumulation of a meaningful body of knowledge on the subject. It is most important therefore that, where there is a possibility of receiving high-level exposure, methods of personnel dosimetry should be available that would provide the dosimetric information most useful to the physician. Provision of good personnel dosimetry for accidental high-level exposure is in many cases an essential part of emergency planning because the information provided may influence emergency and rescue operations, and can lead to improved accident preparedness. Accordingly, the International Atomic Energy Agency and the World Health Organization jointly organized the Symposium on Personnel Dosimetry for Accidental High-Level Exposure to External and Internal Radiation for the discussion of such methods and for a critical review of the procedures adopted in some of the radiation accidents that have already occurred. The meeting was attended by 179 participants from 34 countries and from five other international organizations. The papers presented and the ensuing discussions are published in these Proceedings. It is hoped that the Proceedings will be of help to those concerned with the organization and development of wide-range personnel monitoring systems, and with the interpretation of the results provided

  11. External factors in hospital information system (HIS) adoption model: a case on Malaysia.

    Science.gov (United States)

    Lee, Heng Wei; Ramayah, Thurasamy; Zakaria, Nasriah

    2012-08-01

    Studies related to healthcare ICT integration in Malaysia are relatively little, thus this paper provide a literature review of the integration of information and communication technologies (ICT) in the healthcare sector in Malaysia through the hospital information system (HIS). Our study emphasized on secondary data to investigate the factors related to ICT integration in healthcare through HIS. Therefore this paper aimed to gather an in depth understanding of issues related to HIS adoption, and contributing in fostering HIS adoption in Malaysia and other countries. This paper provides a direction for future research to study the correlation of factors affecting HIS adoption. Finally a research model is proposed using current adoption theories and external factors from human, technology, and organization perspectives.

  12. Secular Orbit Evolution in Systems with a Strong External Perturber—A Simple and Accurate Model

    Energy Technology Data Exchange (ETDEWEB)

    Andrade-Ines, Eduardo [Institute de Mécanique Céleste et des Calcul des Éphémérides—Observatoire de Paris, 77 Avenue Denfert Rochereau, F-75014 Paris (France); Eggl, Siegfried, E-mail: eandrade.ines@gmail.com, E-mail: siegfried.eggl@jpl.nasa.gov [Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Drive, 91109 Pasadena, CA (United States)

    2017-04-01

    We present a semi-analytical correction to the seminal solution for the secular motion of a planet’s orbit under gravitational influence of an external perturber derived by Heppenheimer. A comparison between analytical predictions and numerical simulations allows us to determine corrective factors for the secular frequency and forced eccentricity in the coplanar restricted three-body problem. The correction is given in the form of a polynomial function of the system’s parameters that can be applied to first-order forced eccentricity and secular frequency estimates. The resulting secular equations are simple, straight forward to use, and improve the fidelity of Heppenheimers solution well beyond higher-order models. The quality and convergence of the corrected secular equations are tested for a wide range of parameters and limits of its applicability are given.

  13. Studies on entanglement entropy for Hubbard model with hole-doping and external magnetic field

    International Nuclear Information System (INIS)

    Yao, K.L.; Li, Y.C.; Sun, X.Z.; Liu, Q.M.; Qin, Y.; Fu, H.H.; Gao, G.Y.

    2005-01-01

    By using the density matrix renormalization group (DMRG) method for the one-dimensional (1D) Hubbard model, we have studied the von Neumann entropy of a quantum system, which describes the entanglement of the system block and the rest of the chain. It is found that there is a close relation between the entanglement entropy and properties of the system. The hole-doping can alter the charge-charge and spin-spin interactions, resulting in charge polarization along the chain. By comparing the results before and after the doping, we find that doping favors increase of the von Neumann entropy and thus also favors the exchange of information along the chain. Furthermore, we calculated the spin and entropy distribution in external magnetic filed. It is confirmed that both the charge-charge and the spin-spin interactions affect the exchange of information along the chain, making the entanglement entropy redistribute

  14. Using Physical Context-Based Authentication against External Attacks: Models and Protocols

    Directory of Open Access Journals (Sweden)

    Wilson S. Melo

    2018-01-01

    Full Text Available Modern systems are increasingly dependent on the integration of physical processes and information technologies. This trend is remarkable in applications involving sensor networks, cyberphysical systems, and Internet of Things. Despite its complexity, such integration results in physical context information that can be used to improve security, especially authentication. In this paper, we show that entities sharing the same physical context can use it for establishing a secure communication channel and protecting each other against external attacks. We present such approach proposing a theoretical model for generating unique bitstreams. Two different protocols are suggested. Each one is evaluated using probabilistic analysis and simulation. In the end, we implement the authentication mechanism in a case study using networks radio signal as physical event generator. The results demonstrate the performance of each of the protocols and their suitability for applications in real world.

  15. Modeling and experimental verification of laser self-mixing interference phenomenon with the structure of two-external-cavity feedback

    Science.gov (United States)

    Chen, Peng; Liu, Yuwei; Gao, Bingkun; Jiang, Chunlei

    2018-03-01

    A semiconductor laser employed with two-external-cavity feedback structure for laser self-mixing interference (SMI) phenomenon is investigated and analyzed. The SMI model with two directions based on F-P cavity is deduced, and numerical simulation and experimental verification were conducted. Experimental results show that the SMI with the structure of two-external-cavity feedback under weak light feedback is similar to the sum of two SMIs.

  16. The influence of a fentanyl and dexmedetomidine combination on external respiratory functions in acute hemorrhage model

    Directory of Open Access Journals (Sweden)

    Nikolay G. Vengerovich

    2017-01-01

    Full Text Available Background. The synthetic opioid analgesic fentanyl is widely used for prophylaxis and therapy of traumatic shock associated with massive bleeding. Its side effects – skeletal muscle rigidity and respiratory center depression – are especially pronounced with repeated administration. It is rational to apply fentanyl in diminished doses in combination with non-opioid analgesics in order to reduce respiratory disturbances risk.Aim. The aim of the work is to justify the influence of opioid analgesic fentanyl and α2 -adrenomimetic dexmedetomidine combination on external respiratory functions in acute hemorrhage model.Materials and methods. Acute loss of 35–40% of circulating blood volume was modeled in experiments on 75 white mongrel male rats. The external respiratory functions (respiratory rate, respiratory volume, breath volume per minute were estimated in animals of 5 groups: 1 – rats without analgesic help (controls; 2–3 – rats receiving a single fentanyl intramuscular injection (ED99 98,96 mcg/kg or fentanyl together with dexme detomidine (ED99 of combination 67,94 mcg/kg 15 min after acute blood loss; 4–5 – rats receiving the same drugs 15 min, 30, 45 and 60 min later.Results. In experimental acute loss of 35–40% of circulating blood volume, 15 min later a secondary acute respiratory failure developed with a drop of respiratory rate, respiratory volume and volume of breath per minute by 30%, 21 and 47% (p < 0,05. The external respiratory functions recoverеd after 4 h mainly due to the increase of respiratory volume. A single intramuscular injection of fentanyl caused respiratory depression 15 min after experimental blood loss which resulted in the decrease of breath volume per minute to 30–61% (p < 0,05 for 90 min. Four intramuscular injections of fentanyl 15 min, 30, 45 and 60 min after hemorrhage caused a severe respiratory dysfunction, accompanied by apnea periods and Biot’s respiration. Respiratory rate was reduced

  17. Credibility and reputation: an application of the "external circumstances" model for the Real Plan

    Directory of Open Access Journals (Sweden)

    César A. O. Tejada

    2002-10-01

    Full Text Available This paper analyzes credibility and reputation aspects of the Brazilian economic policy between August 1994 and December 1998. It uses an ''external circumstances'' model, which can be applied to countries with fixed or crawling-peg exchange rate policies. The model assumes that no government can conduct its economic policy with the single objective of inflation control, thoroughly ignoring the unemployment and growth paths. Therefore, in the presence of ''external circumstances'' (unexpected exogenous shocks even a strong anti-inflationary government can be forced to devalue its exchange rate. The results here show that the government followed a consistent policy with inflation control while allowing for a gradual recovery of the competitiveness level.Este artigo analisa a credibilidade e a reputação na política econômica brasileira no período de agosto de 1994 a dezembro de 1998. O marco teórico empregado tem como base o modelo de ''circunstâncias externas'', que permite analisar os fatores de credibilidade e reputação durante o funcionamento de um regime de taxa de câmbio fixa ou de crawling peg. O modelo parte do pressuposto de que, em geral, nenhum governo pode preocupar-se única e exclusivamente com o objetivo de controlar a inflação, ignorando por completo objetivos de crescimento e emprego. Portanto, e em particular, diante de circunstâncias adversas, um governo, ainda que do tipo antiinflação, pode ser levado a desvalorizar a taxa de câmbio. Os resultados aqui apresentados permitem concluir que o governo estava seguindo uma política consistente com a manutenção da estabilidade de preços, enquanto permitia uma recuperação gradual da competitividade.

  18. Axial displacement of external and internal implant-abutment connection evaluated by linear mixed model analysis.

    Science.gov (United States)

    Seol, Hyon-Woo; Heo, Seong-Joo; Koak, Jai-Young; Kim, Seong-Kyun; Kim, Shin-Koo

    2015-01-01

    To analyze the axial displacement of external and internal implant-abutment connection after cyclic loading. Three groups of external abutments (Ext group), an internal tapered one-piece-type abutment (Int-1 group), and an internal tapered two-piece-type abutment (Int-2 group) were prepared. Cyclic loading was applied to implant-abutment assemblies at 150 N with a frequency of 3 Hz. The amount of axial displacement, the Periotest values (PTVs), and the removal torque values(RTVs) were measured. Both a repeated measures analysis of variance and pattern analysis based on the linear mixed model were used for statistical analysis. Scanning electron microscopy (SEM) was used to evaluate the surface of the implant-abutment connection. The mean axial displacements after 1,000,000 cycles were 0.6 μm in the Ext group, 3.7 μm in the Int-1 group, and 9.0 μm in the Int-2 group. Pattern analysis revealed a breakpoint at 171 cycles. The Ext group showed no declining pattern, and the Int-1 group showed no declining pattern after the breakpoint (171 cycles). However, the Int-2 group experienced continuous axial displacement. After cyclic loading, the PTV decreased in the Int-2 group, and the RTV decreased in all groups. SEM imaging revealed surface wear in all groups. Axial displacement and surface wear occurred in all groups. The PTVs remained stable, but the RTVs decreased after cyclic loading. Based on linear mixed model analysis, the Ext and Int-1 groups' axial displacements plateaued after little cyclic loading. The Int-2 group's rate of axial displacement slowed after 100,000 cycles.

  19. Unified model to predict flexural shear behavior of externally bonded RC beams

    International Nuclear Information System (INIS)

    Colotti, V.; Spadea, G.; Swamy, R.N.

    2006-01-01

    Structural strengthening with externally bonded reinforcement is now recognized as a cost-effective, structurally sound and practically efficient method of rehabilitating deteriorating and damaged reinforced concrete beams. There is now an urgent need to develop a sound engineering basis which can predict the failure loads of all such strengthened beams in a reliable and consistent manner. Existing models to predict the behavior at ultimate of strengthened beams suffer from many limitations and weaknesses. This paper presents a unified global model, based on the Strut-and-Tie approach, to predict the failure loads of reinforced concrete beams strengthened for flexure and/or shear. This structural model is based on rational engineering principles, considers all the possible failure modes, and incorporates the load transfer mechanism bond to reflect the debonding phenomena which has a dominant influence on the failure process of plated beams. The model is validated against about 200 strengthened beam test reported in the literature and failing in flexure and/or shear, involving a large number of structural variables and steel, carbon and glass fiber reinforced polymer laminates as reinforcing medium. (author)

  20. External intermittency prediction using AMR solutions of RANS turbulence and transported PDF models

    Science.gov (United States)

    Olivieri, D. A.; Fairweather, M.; Falle, S. A. E. G.

    2011-12-01

    External intermittency in turbulent round jets is predicted using a Reynolds-averaged Navier-Stokes modelling approach coupled to solutions of the transported probability density function (pdf) equation for scalar variables. Solutions to the descriptive equations are obtained using a finite-volume method, combined with an adaptive mesh refinement algorithm, applied in both physical and compositional space. This method contrasts with conventional approaches to solving the transported pdf equation which generally employ Monte Carlo techniques. Intermittency-modified eddy viscosity and second-moment turbulence closures are used to accommodate the effects of intermittency on the flow field, with the influence of intermittency also included, through modifications to the mixing model, in the transported pdf equation. Predictions of the overall model are compared with experimental data on the velocity and scalar fields in a round jet, as well as against measurements of intermittency profiles and scalar pdfs in a number of flows, with good agreement obtained. For the cases considered, predictions based on the second-moment turbulence closure are clearly superior, although both turbulence models give realistic predictions of the bimodal scalar pdfs observed experimentally.

  1. Simple wealth distribution model causing inequality-induced crisis without external shocks

    Science.gov (United States)

    Benisty, Henri

    2017-05-01

    We address the issue of the dynamics of wealth accumulation and economic crisis triggered by extreme inequality, attempting to stick to most possibly intrinsic assumptions. Our general framework is that of pure or modified multiplicative processes, basically geometric Brownian motions. In contrast with the usual approach of injecting into such stochastic agent models either specific, idiosyncratic internal nonlinear interaction patterns or macroscopic disruptive features, we propose a dynamic inequality model where the attainment of a sizable fraction of the total wealth by very few agents induces a crisis regime with strong intermittency, the explicit coupling between the richest and the rest being a mere normalization mechanism, hence with minimal extrinsic assumptions. The model thus harnesses the recognized lack of ergodicity of geometric Brownian motions. It also provides a statistical intuition to the consequences of Thomas Piketty's recent "r >g " (return rate > growth rate) paradigmatic analysis of very-long-term wealth trends. We suggest that the "water-divide" of wealth flow may define effective classes, making an objective entry point to calibrate the model. Consistently, we check that a tax mechanism associated to a few percent relative bias on elementary daily transactions is able to slow or stop the build-up of large wealth. When extreme fluctuations are tamed down to a stationary regime with sizable but steadier inequalities, it should still offer opportunities to study the dynamics of crisis and the inner effective classes induced through external or internal factors.

  2. Derivation and external validation of a case mix model for the standardized reporting of 30-day stroke mortality rates.

    Science.gov (United States)

    Bray, Benjamin D; Campbell, James; Cloud, Geoffrey C; Hoffman, Alex; James, Martin; Tyrrell, Pippa J; Wolfe, Charles D A; Rudd, Anthony G

    2014-11-01

    Case mix adjustment is required to allow valid comparison of outcomes across care providers. However, there is a lack of externally validated models suitable for use in unselected stroke admissions. We therefore aimed to develop and externally validate prediction models to enable comparison of 30-day post-stroke mortality outcomes using routine clinical data. Models were derived (n=9000 patients) and internally validated (n=18 169 patients) using data from the Sentinel Stroke National Audit Program, the national register of acute stroke in England and Wales. External validation (n=1470 patients) was performed in the South London Stroke Register, a population-based longitudinal study. Models were fitted using general estimating equations. Discrimination and calibration were assessed using receiver operating characteristic curve analysis and correlation plots. Two final models were derived. Model A included age (<60, 60-69, 70-79, 80-89, and ≥90 years), National Institutes of Health Stroke Severity Score (NIHSS) on admission, presence of atrial fibrillation on admission, and stroke type (ischemic versus primary intracerebral hemorrhage). Model B was similar but included only the consciousness component of the NIHSS in place of the full NIHSS. Both models showed excellent discrimination and calibration in internal and external validation. The c-statistics in external validation were 0.87 (95% confidence interval, 0.84-0.89) and 0.86 (95% confidence interval, 0.83-0.89) for models A and B, respectively. We have derived and externally validated 2 models to predict mortality in unselected patients with acute stroke using commonly collected clinical variables. In settings where the ability to record the full NIHSS on admission is limited, the level of consciousness component of the NIHSS provides a good approximation of the full NIHSS for mortality prediction. © 2014 American Heart Association, Inc.

  3. Measurements and evaluation of the risks due to external radiation exposures and to intake of activated elements for operational staff engaged in the maintenance of medical cyclotrons.

    Science.gov (United States)

    Calandrino, R; del Vecchio, A; Parisi, R; Todde, S; De Felice, P; Savi, A; Pepe, A; Mrskova, A

    2010-06-01

    The aim of this paper is to assess the activation phenomena and to evaluate the risk of external exposure and intake doses for the maintenance staff of two medical cyclotrons. Two self-shielded cyclotrons are currently operating in the facility for the routine production of (11)C and (18)F. Four radiochemistry laboratories are linked to the cyclotrons by means of shielded radioisotope delivery lines. Radiopharmaceuticals are prepared both for the PET Diagnostic Department, where four CT-PET scanners are operating with a mean patient workload of 40 d(-1) and for [(18)F]FDG external distribution, to provide radiopharmaceuticals for other institutions. In spite of the fact that air contamination inside the radiochemistry laboratories during the synthesis represents the largest 'slice of the pie' in the evaluation of annual intake dose, potential contamination due to the activated particulate, generated during cyclotron irradiation by micro-corrosion of targets and other components potentially struck by the proton beam and generated neutrons, should be considered. In this regard, the most plausible long-lived (T(1/2) > 30 d) radioisotopes formed are: (97)Tc, (56)Co, (57)Co, (58)Co, (60)Co, (49)V, (55)Fe, (109)Cd, (65)Zn and (22)Na. The results for the operating personnel survey has revealed only low-level contamination for (65)Zn in one test, together with minor (18)F intake, probably due to the environmental dispersion of the radioisotope during the [(18)F]FDG synthesis.

  4. SHEDS-HT: an integrated probabilistic exposure model for prioritizing exposures to chemicals with near-field and dietary sources.

    Science.gov (United States)

    Isaacs, Kristin K; Glen, W Graham; Egeghy, Peter; Goldsmith, Michael-Rock; Smith, Luther; Vallero, Daniel; Brooks, Raina; Grulke, Christopher M; Özkaynak, Halûk

    2014-11-04

    United States Environmental Protection Agency (USEPA) researchers are developing a strategy for high-throughput (HT) exposure-based prioritization of chemicals under the ExpoCast program. These novel modeling approaches for evaluating chemicals based on their potential for biologically relevant human exposures will inform toxicity testing and prioritization for chemical risk assessment. Based on probabilistic methods and algorithms developed for The Stochastic Human Exposure and Dose Simulation Model for Multimedia, Multipathway Chemicals (SHEDS-MM), a new mechanistic modeling approach has been developed to accommodate high-throughput (HT) assessment of exposure potential. In this SHEDS-HT model, the residential and dietary modules of SHEDS-MM have been operationally modified to reduce the user burden, input data demands, and run times of the higher-tier model, while maintaining critical features and inputs that influence exposure. The model has been implemented in R; the modeling framework links chemicals to consumer product categories or food groups (and thus exposure scenarios) to predict HT exposures and intake doses. Initially, SHEDS-HT has been applied to 2507 organic chemicals associated with consumer products and agricultural pesticides. These evaluations employ data from recent USEPA efforts to characterize usage (prevalence, frequency, and magnitude), chemical composition, and exposure scenarios for a wide range of consumer products. In modeling indirect exposures from near-field sources, SHEDS-HT employs a fugacity-based module to estimate concentrations in indoor environmental media. The concentration estimates, along with relevant exposure factors and human activity data, are then used by the model to rapidly generate probabilistic population distributions of near-field indirect exposures via dermal, nondietary ingestion, and inhalation pathways. Pathway-specific estimates of near-field direct exposures from consumer products are also modeled

  5. How Do Internal and External CSR Affect Employees' Organizational Identification? A Perspective from the Group Engagement Model.

    Science.gov (United States)

    Hameed, Imran; Riaz, Zahid; Arain, Ghulam A; Farooq, Omer

    2016-01-01

    The literature examines the impact of firms' corporate social responsibility (CSR) activities on employees' organizational identification without considering that such activities tend to have different targets. This study explores how perceived external CSR (efforts directed toward external stakeholders) and perceived internal CSR (efforts directed toward employees) activities influence employees' organizational identification. In so doing, it examines the alternative underlying mechanisms through which perceived external and internal CSR activities build employees' identification. Applying the taxonomy prescribed by the group engagement model, the study argues that the effects of perceived external and internal CSR flow through two competing mechanisms: perceived external prestige and perceived internal respect, respectively. Further, it is suggested that calling orientation (how employees see their work contributions) moderates the effects induced by these alternative forms of CSR. The model draws on survey data collected from a sample of 414 employees across five large multinationals in Pakistan. The results obtained using structural equation modeling support these hypotheses, reinforcing the notion that internal and external CSR operate through different mediating mechanisms and more interestingly employees' calling orientation moderates these relationships to a significant degree. Theoretical contributions and practical implications of results are discussed in detail.

  6. Inhalation Exposure Input Parameters for the Biosphere Model

    Energy Technology Data Exchange (ETDEWEB)

    M. Wasiolek

    2006-06-05

    This analysis is one of the technical reports that support the Environmental Radiation Model for Yucca Mountain, Nevada (ERMYN), referred to in this report as the biosphere model. ''Biosphere Model Report'' (BSC 2004 [DIRS 169460]) describes in detail the conceptual model as well as the mathematical model and its input parameters. This report documents development of input parameters for the biosphere model that are related to atmospheric mass loading and supports the use of the model to develop biosphere dose conversion factors (BDCFs). The biosphere model is one of a series of process models supporting the total system performance assessment (TSPA) for a Yucca Mountain repository. ''Inhalation Exposure Input Parameters for the Biosphere Model'' is one of five reports that develop input parameters for the biosphere model. A graphical representation of the documentation hierarchy for the biosphere model is presented in Figure 1-1 (based on BSC 2006 [DIRS 176938]). This figure shows the interrelationships among the products (i.e., analysis and model reports) developed for biosphere modeling and how this analysis report contributes to biosphere modeling. This analysis report defines and justifies values of atmospheric mass loading for the biosphere model. Mass loading is the total mass concentration of resuspended particles (e.g., dust, ash) in a volume of air. Mass loading values are used in the air submodel of the biosphere model to calculate concentrations of radionuclides in air inhaled by a receptor and concentrations in air surrounding crops. Concentrations in air to which the receptor is exposed are then used in the inhalation submodel to calculate the dose contribution to the receptor from inhalation of contaminated airborne particles. Concentrations in air surrounding plants are used in the plant submodel to calculate the concentrations of radionuclides in foodstuffs contributed from uptake by foliar interception. This

  7. Inhalation Exposure Input Parameters for the Biosphere Model

    International Nuclear Information System (INIS)

    M. Wasiolek

    2006-01-01

    This analysis is one of the technical reports that support the Environmental Radiation Model for Yucca Mountain, Nevada (ERMYN), referred to in this report as the biosphere model. ''Biosphere Model Report'' (BSC 2004 [DIRS 169460]) describes in detail the conceptual model as well as the mathematical model and its input parameters. This report documents development of input parameters for the biosphere model that are related to atmospheric mass loading and supports the use of the model to develop biosphere dose conversion factors (BDCFs). The biosphere model is one of a series of process models supporting the total system performance assessment (TSPA) for a Yucca Mountain repository. ''Inhalation Exposure Input Parameters for the Biosphere Model'' is one of five reports that develop input parameters for the biosphere model. A graphical representation of the documentation hierarchy for the biosphere model is presented in Figure 1-1 (based on BSC 2006 [DIRS 176938]). This figure shows the interrelationships among the products (i.e., analysis and model reports) developed for biosphere modeling and how this analysis report contributes to biosphere modeling. This analysis report defines and justifies values of atmospheric mass loading for the biosphere model. Mass loading is the total mass concentration of resuspended particles (e.g., dust, ash) in a volume of air. Mass loading values are used in the air submodel of the biosphere model to calculate concentrations of radionuclides in air inhaled by a receptor and concentrations in air surrounding crops. Concentrations in air to which the receptor is exposed are then used in the inhalation submodel to calculate the dose contribution to the receptor from inhalation of contaminated airborne particles. Concentrations in air surrounding plants are used in the plant submodel to calculate the concentrations of radionuclides in foodstuffs contributed from uptake by foliar interception. This report is concerned primarily with the

  8. External radiation surveillance

    International Nuclear Information System (INIS)

    Antonio, E.J.

    1995-01-01

    This section of the 1994 Hanford Site Environmental Report describes how external radiation was measured, how surveys were performed, and the results of these measurements and surveys. External radiation exposure rates were measured at locations on and off the Hanford Site using thermoluminescent dosimeters (TLD). External radiation and contamination surveys were also performed with portable radiation survey instruments at locations on and around the Hanford Site

  9. External radiation surveillance

    Energy Technology Data Exchange (ETDEWEB)

    Antonio, E.J.

    1995-06-01

    This section of the 1994 Hanford Site Environmental Report describes how external radiation was measured, how surveys were performed, and the results of these measurements and surveys. External radiation exposure rates were measured at locations on and off the Hanford Site using thermoluminescent dosimeters (TLD). External radiation and contamination surveys were also performed with portable radiation survey instruments at locations on and around the Hanford Site.

  10. Human Exposure Model (HEM): A modular, web-based application to characterize near-field chemical exposures and releases

    Science.gov (United States)

    The U.S. EPA’s Chemical Safety and Sustainability research program is developing the Human Exposure Model (HEM) to assess near-field exposures to chemicals that occur in various populations over the entire life cycle of a consumer product. The model will be implemented as a...

  11. Hebbian plasticity realigns grid cell activity with external sensory cues in continuous attractor models

    Directory of Open Access Journals (Sweden)

    Marcello eMulas

    2016-02-01

    Full Text Available After the discovery of grid cells, which are an essential component to understand how the mammalian brain encodes spatial information, three main classes of computational models were proposed in order to explain their working principles. Amongst them, the one based on continuous attractor networks (CAN, is promising in terms of biological plausibility and suitable for robotic applications. However, in its current formulation, it is unable to reproduce important electrophysiological findings and cannot be used to perform path integration for long periods of time. In fact, in absence of an appropriate resetting mechanism, the accumulation of errors overtime due to the noise intrinsic in velocity estimation and neural computation prevents CAN models to reproduce stable spatial grid patterns. In this paper, we propose an extension of the CAN model using Hebbian plasticity to anchor grid cell activity to environmental landmarks. To validate our approach we used as input to the neural simulations both artificial data and real data recorded from a robotic setup. The additional neural mechanism can not only anchor grid patterns to external sensory cues but also recall grid patterns generated in previously explored environments. These results might be instrumental for next generation bio-inspired robotic navigation algorithms that take advantage of neural computation in order to cope with complex and dynamic environments.

  12. Flowing states and vortices in the classical XY model in an external field

    International Nuclear Information System (INIS)

    Homma, Shigeo; Aoki, Toshizumi; Takeno, Shozo.

    1981-01-01

    Uniformly flowing states and vortices in the classical XY model in an external field are studied. This is done by using a continuum approximation and by paying attention to particular solutions to nonlinear partial differential equations for two angles theta and phi of rotation of spins for which phi satisfies the Laplace equation. For these two states equations for theta have forms similar to that in the classical Ising model in a transverse field. The uniformly flowing states are therefore described by kink-type excitations identical to those in the two-dimensional Ising model. Phonon modes associated with the uniformly flowing states are also studied, which are similar to Bogoliubov phonons. Vortex solutions and vortex formation energy are studied in close similarity to the case of liquid He 4 . By comparing the energies of these two states, an expression for critical velocity is obtained. By making correspondence to the case of liquid He 4 , numerical values of the critical velocity and of the velocity of phonons around the uniformly flowing states are estimated. For the former the numerical value is in fair agreement with experimental data. (author)

  13. Predicting the success of IVF: external validation of the van Loendersloot's model.

    Science.gov (United States)

    Sarais, Veronica; Reschini, Marco; Busnelli, Andrea; Biancardi, Rossella; Paffoni, Alessio; Somigliana, Edgardo

    2016-06-01

    Is the predictive model for IVF success proposed by van Loendersloot et al. valid in a different geographical and cultural context? The model discriminates well but was less accurate than in the original context where it was developed. Several independent groups have developed models that combine different variables with the aim of estimating the chance of pregnancy with IVF but only four of them have been externally validated. One of these four, the van Loendersloot's model, deserves particular attention and further investigation for at least three reasons; (i) the reported area under the receiver operating characteristics curve (c-statistics) in the temporal validation setting was the highest reported to date (0.68), (ii) the perspective of the model is clinically wise since it includes variables obtained from previous failed cycles, if any, so it can be applied to any women entering an IVF cycle, (iii) the model lacks external validation in a geographically different center. Retrospective cohort study of women undergoing oocyte retrieval for IVF between January 2013 and December 2013 at the infertility unit of the Fondazione Ca' Granda, Ospedale Maggiore Policlinico of Milan, Italy. Only the first oocyte retrieval cycle performed during the study period was included in the study. Women with previous IVF cycles were excluded if the last one before the study cycle was in another center. The main outcome was the cumulative live birth rate per oocytes retrieval. Seven hundred seventy-two women were selected. Variables included in the van Loendersloot's model and the relative weights (beta) were used. The variable resulting from this combination (Y) was transformed into a probability. The discriminatory capacity was assessed using the c-statistics. Calibration was made using a logistic regression that included Y as the unique variable and live birth as the outcome. Data are presented using both the original and the calibrated models. Performance was evaluated

  14. The assumption of heterogeneous or homogeneous radioactive contamination in soil/sediment: does it matter in terms of the external exposure of fauna?

    Science.gov (United States)

    Beaugelin-Seiller, K

    2014-12-01

    The classical approach to environmental radioprotection is based on the assumption of homogeneously contaminated media. However, in soils and sediments there may be a significant variation of radioactivity with depth. The effect of this heterogeneity was investigated by examining the external exposure of various sediment and soil organisms, and determining the resulting dose rates, assuming a realistic combination of locations and radionuclides. The results were dependent on the exposure situation, i.e., the organism, its location, and the quality and quantity of radionuclides. The dose rates ranged over three orders of magnitude. The assumption of homogeneous contamination was not consistently conservative (if associated with a level of radioactivity averaged over the full thickness of soil or sediment that was sampled). Dose assessment for screening purposes requires consideration of the highest activity concentration measured in a soil/sediment that is considered to be homogeneously contaminated. A more refined assessment (e.g., higher tier of a graded approach) should take into consideration a more realistic contamination profile, and apply different dosimetric approaches. Copyright © 2014 Elsevier Ltd. All rights reserved.

  15. Mortality through 1990 among white male workers at the Los Alamos National Laboratory: Considering exposures to plutonium and external ionizing radiation

    International Nuclear Information System (INIS)

    Wiggs, L.D.; Johnson, E.R.; Cox-DeVore, C.A.; Voelz, G.L.

    1994-01-01

    A cohort mortality study was conducted of 15,727 white men employed by the Los Alamos National Laboratory, a nuclear research and development facility. Some of the workers at this facility have been exposed to various forms of ionizing radiation and other potentially hazardous materials. These analyses focused on whole-body ionizing radiation exposures and internal depositions of plutonium. The results indicated that overall mortality among this cohort is quite low, even after nearly 30 y of follow-up. No cause of death was significantly elevated among plutonium-exposed workers when compared with their unexposed coworkers; however, a rate ratio for lung cancer of 1.78 (95% CI = 0.79-3.99) was observed. A case of osteogenic sarcoma, a type of cancer related to plutonium exposure in animal studies, was also observed. Dose-response relationships for whole-body dose from external ionizing radiation and tritium were observed for cancers of the brain/central nervous system, the esophagus, and Hodgkin's disease. 34 refs., 1 fig., 7 tabs

  16. Econometric model for age- and population-dependent radiation exposures

    International Nuclear Information System (INIS)

    Sandquist, G.M.; Slaughter, D.M.; Rogers, V.C.

    1991-01-01

    The economic impact associated with ionizing radiation exposures in a given human population depends on numerous factors including the individual's mean economic status as a function age, the age distribution of the population, the future life expectancy at each age, and the latency period for the occurrence of radiation-induced health effects. A simple mathematical model has been developed that provides an analytical methodology for estimating the societal econometrics associated with radiation effects are to be assessed and compared for economic evaluation

  17. When Students Doubt Their Teachers' Diagnostic Competence: Moderation in the Internal/External Frame of Reference Model

    Science.gov (United States)

    Zimmermann, Friederike; Möller, Jens; Köller, Olaf

    2018-01-01

    The internal/external frame of reference model (I/E model) posits that individuals' achievement-related self-concepts are formed through social comparisons (e.g., self vs. peers) within academic domains and dimensional comparisons (e.g., math vs. verbal) between distinct domains. A large body of research has supported the theorized pattern of…

  18. Predicting Internalizing and Externalizing Symptoms in Children with ASD: Evaluation of a Contextual Model of Parental Factors

    Science.gov (United States)

    McRae, Elizabeth M.; Stoppelbein, Laura; O'Kelley, Sarah E.; Fite, Paula; Greening, Leilani

    2018-01-01

    Parental adjustment, parenting behaviors, and child routines have been linked to internalizing and externalizing child behavior. The purpose of the present study was to evaluate a comprehensive model examining relations among these variables in children with ASD and their parents. Based on Sameroff's Transactional Model of Development (Sameroff…

  19. Prognosis in moderate and severe traumatic brain injury: External validation of the IMPACT models and the role of extracranial injuries

    NARCIS (Netherlands)

    Lingsma, Hester; Andriessen, Teuntje M. J. C.; Haitsema, Iain; Horn, Janneke; van der Naalt, Joukje; Franschman, Gaby; Maas, Andrew I. R.; Vos, Pieter E.; Steyerberg, Ewout W.

    2013-01-01

    BACKGROUND: Several prognostic models to predict outcome in traumatic brain injury (TBI) have been developed, but few are externally validated. We aimed to validate the International Mission on Prognosis and Analysis of Clinical Trials in TBI (IMPACT) prognostic models in a recent unselected patient

  20. Modelling of aircrew radiation exposure during solar particle events

    Science.gov (United States)

    Al Anid, Hani Khaled

    show a very different response during anisotropic events, leading to variations in aircrew radiation doses that may be significant for dose assessment. To estimate the additional exposure due to solar flares, a model was developed using a Monte-Carlo radiation transport code, MCNPX. The model transports an extrapolated particle spectrum based on satellite measurements through the atmosphere using the MCNPX analysis. This code produces the estimated flux at a specific altitude where radiation dose conversion coefficients are applied to convert the particle flux into effective and ambient dose-equivalent rates. A cut-off rigidity model accounts for the shielding effects of the Earth's magnetic field. Comparisons were made between the model predictions and actual flight measurements taken with various types of instruments used to measure the mixed radiation field during Ground Level Enhancements 60 and 65. An anisotropy analysis that uses neutron monitor responses and the pitch angle distribution of energetic solar particles was used to identify particle anisotropy for a solar event in December 2006. In anticipation of future commercial use, a computer code has been developed to implement the radiation dose assessment model for routine analysis. Keywords: Radiation Dosimetry, Radiation Protection, Space Physics.

  1. Discrete event simulation model for external yard choice of import container terminal in a port buffer area

    Science.gov (United States)

    Rusgiyarto, Ferry; Sjafruddin, Ade; Frazila, Russ Bona; Suprayogi

    2017-06-01

    Increasing container traffic and land acquisition problem for terminal expansion leads to usage of external yard in a port buffer area. This condition influenced the terminal performance because a road which connects the terminal and the external yard was also used by non-container traffic. Location choice problem considered to solve this condition, but the previous research has not taken account a stochastic condition of container arrival rate and service time yet. Bi-level programming framework was used to find optimum location configuration. In the lower-level, there was a problem to construct the equation, which correlated the terminal operation and the road due to different time cycle equilibrium. Container moves from the quay to a terminal gate in a daily unit of time, meanwhile, it moves from the terminal gate to the external yard through the road in a minute unit of time. If the equation formulated in hourly unit equilibrium, it cannot catch up the container movement characteristics in the terminal. Meanwhile, if the equation formulated in daily unit equilibrium, it cannot catch up the road traffic movement characteristics in the road. This problem can be addressed using simulation model. Discrete Event Simulation Model was used to simulate import container flow processes in the container terminal and external yard. Optimum location configuration in the upper-level was the combinatorial problem, which was solved by Full Enumeration approach. The objective function of the external yard location model was to minimize user transport cost (or time) and to maximize operator benefit. Numerical experiment was run for the scenario assumption of two container handling ways, three external yards, and thirty-day simulation periods. Jakarta International Container Terminal (JICT) container characteristics data was referred for the simulation. Based on five runs which were 5, 10, 15, 20, and 30 repetitions, operation one of three available external yards (external yard

  2. Parent-child relationship quality and family transmission of parent posttraumatic stress disorder symptoms and child externalizing and internalizing symptoms following fathers' exposure to combat trauma.

    Science.gov (United States)

    Snyder, James; Gewirtz, Abigail; Schrepferman, Lynn; Gird, Suzanne R; Quattlebaum, Jamie; Pauldine, Michael R; Elish, Katie; Zamir, Osnat; Hayes, Charles

    2016-11-01

    Transactional cascades among child internalizing and externalizing symptoms, and fathers' and mothers' posttraumatic stress disorder (PTSD) symptoms were examined in a sample of families with a male parent who had been deployed to recent military conflicts in the Middle East. The role of parents' positive engagement and coercive interaction with their child, and family members' emotion regulation were tested as processes linking cascades of parent and child symptoms. A subsample of 183 families with deployed fathers and nondeployed mothers and their 4- to 13-year-old children who participated in a randomized control trial intervention (After Deployment: Adaptive Parenting Tools) were assessed at baseline prior to intervention, and at 12 and 24 months after baseline, using parent reports of their own and their child's symptoms. Parents' observed behavior during interaction with their children was coded using a multimethod approach at each assessment point. Reciprocal cascades among fathers' and mothers' PTSD symptoms, and child internalizing and externalizing symptoms, were observed. Fathers' and mothers' positive engagement during parent-child interaction linked their PTSD symptoms and their child's internalizing symptoms. Fathers' and mothers' coercive behavior toward their child linked their PTSD symptoms and their child's externalizing symptoms. Each family member's capacity for emotion regulation was associated with his or her adjustment problems at baseline. Implications for intervention, and for research using longitudinal models and a family-systems perspective of co-occurrence and cascades of symptoms across family members are described.

  3. Parent-Child Relationship Quality and Family Transmission of Parent Posttraumatic Stress Disorder Symptoms and Child Externalizing and Internalizing Symptoms Following Fathers’ Combat-Trauma Exposure

    Science.gov (United States)

    Snyder, James; Gewirtz, Abigail; Schrepferman, Lynn; Gird, Suzanne R.; Quattlebaum, Jamie; Pauldine, Michael R.; Elish, Katie; Zamir, Osnat; Hayes, Charles

    2016-01-01

    Transactional cascades among child internalizing and externalizing symptoms, and fathers’ and mothers’ post-traumatic stress disorder symptoms were examined in a sample of families with a male parent who had been deployed to recent military conflicts in the Middle East. The role of parents’ positive engagement and coercive interaction with their child, and family members’ emotion regulation were tested as processes linking cascades of parent and child symptoms. A subsample of 183 families with deployed fathers and non-deployed mothers and their 4 to 13 year old children who participated in a randomized control trial intervention (After Deployment: Adaptive Parenting Tools, or ADAPT) were assessed at baseline prior to intervention, and at 12 and 24 months after baseline, using parent reports of their own and their child’s symptoms. Parents’ observed behavior during interaction with their children was coded using a multi-method approach at each assessment point. Reciprocal cascades among fathers’ and mothers’ PTSD symptoms, and child internalizing and externalizing symptoms were observed. Fathers’ and mothers’ positive engagement during parent-child interaction linked their PTSD symptoms and their child’s internalizing symptoms. Fathers’ and mothers’ coercive behavior toward their child linked their PTSD symptoms and their child’s externalizing symptoms. Each family members’ capacity for emotion regulation was associated with their adjustment problems at baseline. Implications for intervention, and for research using longitudinal models and a family-systems perspective of co-occurrence and cascades of symptoms across family members are described. PMID:27739388

  4. External Economies Evaluation of Wind Power Engineering Project Based on Analytic Hierarchy Process and Matter-Element Extension Model

    Directory of Open Access Journals (Sweden)

    Hong-ze Li

    2013-01-01

    Full Text Available The external economies of wind power engineering project may affect the operational efficiency of wind power enterprises and sustainable development of wind power industry. In order to ensure that the wind power engineering project is constructed and developed in a scientific manner, a reasonable external economies evaluation needs to be performed. Considering the interaction relationship of the evaluation indices and the ambiguity and uncertainty inherent, a hybrid model of external economies evaluation designed to be applied to wind power engineering project was put forward based on the analytic hierarchy process (AHP and matter-element extension model in this paper. The AHP was used to determine the weights of indices, and the matter-element extension model was used to deduce final ranking. Taking a wind power engineering project in Inner Mongolia city as an example, the external economies evaluation is performed by employing this hybrid model. The result shows that the external economies of this wind power engineering project are belonged to the “strongest” level, and “the degree of increasing region GDP,” “the degree of reducing pollution gas emissions,” and “the degree of energy conservation” are the sensitive indices.

  5. Attributing Asymmetric Productivity Responses to Internal Ecosystem Dynamics and External Drivers Using Probabilistic Models

    Science.gov (United States)

    Parolari, A.; Goulden, M.

    2017-12-01

    A major challenge to interpreting asymmetric changes in ecosystem productivity is the attribution of these changes to external climate forcing or to internal ecophysiological processes that respond to these drivers (e.g., photosynthesis response to drying soil). For example, positive asymmetry in productivity can result from either positive skewness in the distribution of annual rainfall amount or from negative curvature in the productivity response to annual rainfall. To analyze the relative influences of climate and ecosystem dynamics on both positive and negative asymmetry in multi-year ANPP experiments, we use a multi-scale coupled ecosystem water-carbon model to interpret field experimental results that span gradients of rainfall skewness and ANPP response curvature. The model integrates rainfall variability, soil moisture dynamics, and net carbon assimilation from the daily to inter-annual scales. From the underlying physical basis of the model, we compute the joint probability distribution of the minimum and maximum ANPP for an annual ANPP experiment of N years. The distribution is used to estimate the likelihood that either positive or negative asymmetry will be observed in an experiment, given the annual rainfall distribution and the ANPP response curve. We estimate the total asymmetry as the mode of this joint distribution and the relative contribution attributable to rainfall skewness as the mode for a linear ANPP response curve. Applied to data from several long-term ANPP experiments, we find that there is a wide range of observed ANPP asymmetry (positive and negative) and a spectrum of contributions from internal and external factors. We identify the soil water holding capacity relative to the mean rain event depth as a critical ecosystem characteristic that controls the non-linearity of the ANPP response and positive curvature at high rainfall. Further, the seasonal distribution of rainfall is shown to control the presence or absence of negative

  6. External Validity and Model Validity: A Conceptual Approach for Systematic Review Methodology

    Directory of Open Access Journals (Sweden)

    Raheleh Khorsan

    2014-01-01

    Full Text Available Background. Evidence rankings do not consider equally internal (IV, external (EV, and model validity (MV for clinical studies including complementary and alternative medicine/integrative health care (CAM/IHC research. This paper describe this model and offers an EV assessment tool (EVAT© for weighing studies according to EV and MV in addition to IV. Methods. An abbreviated systematic review methodology was employed to search, assemble, and evaluate the literature that has been published on EV/MV criteria. Standard databases were searched for keywords relating to EV, MV, and bias-scoring from inception to Jan 2013. Tools identified and concepts described were pooled to assemble a robust tool for evaluating these quality criteria. Results. This study assembled a streamlined, objective tool to incorporate for the evaluation of quality of EV/MV research that is more sensitive to CAM/IHC research. Conclusion. Improved reporting on EV can help produce and provide information that will help guide policy makers, public health researchers, and other scientists in their selection, development, and improvement in their research-tested intervention. Overall, clinical studies with high EV have the potential to provide the most useful information about “real-world” consequences of health interventions. It is hoped that this novel tool which considers IV, EV, and MV on equal footing will better guide clinical decision making.

  7. Monsoonal Responses to External Forcings over the Past Millennium: A Model Study (Invited)

    Science.gov (United States)

    Liu, J.; Wang, B.

    2009-12-01

    The climate variations related to Global Monsoon (GM) and East Asian summer monsoon (EASM) rainfall over the past 1000 years were investigated by analysis of a pair of millennium simulations with the coupled climate model named ECHO-G. The free run was generated using fixed external (annual cycle) forcing, while the forced run was obtained using time-varying solar irradiance variability, greenhouse gases (CO2 and CH4) concentration and estimated radiative effect of volcanic aerosols. The model results indicate that the centennial-millennial variation of the GM and EASM is essentially a forced response to the external radiative forcings (insolation, volcanic aerosols, and greenhouse gases). The GM strength responds more directly to the effective solar forcing (insolation plus radiative effect of the volcanoes) when compared to responses of the global mean surface temperature on centennial timescale. The simulated GM precipitation in the forced run exhibits a significant quasi-bi-centennial oscillation. Weak GM precipitation was simulated during the Little Ice Age (1450-1850) with three weakest periods concurring with the Spörer, Maunder, and Dalton Minimum of solar activity. Conversely, strong GM was simulated during the model Medieval Warm Period (ca. 1030-1240). Before the industrial period, the natural variation in effective solar forcing reinforces the thermal contrasts both between the ocean and continent and between the northern and southern hemispheres, resulting in millennium-scale variation and the quasi-bi-centennial oscillation of the GM. The prominent upward trend in the GM precipitation occurring in the last century and the remarkably strengthening of the global monsoon in the period of 1961-1990 appear unprecedented and owed possibly in part to the increase of atmospheric carbon dioxide concentration. The EASM has the largest meridional extent (5oN-55oN) among all the regional monsoons on globe. Thus, the EASM provides an unique opportunity for

  8. A Mediation Model of Interparental Collaboration, Parenting Practices, and Child Externalizing Behavior in a Clinical Sample

    Science.gov (United States)

    Kjobli, John; Hagen, Kristine Amlund

    2009-01-01

    The present study examined maternal and paternal parenting practices as mediators of the link between interparental collaboration and children's externalizing behavior. Parent gender was tested as a moderator of the associations. A clinical sample consisting of 136 children with externalizing problems and their families participated in the study.…

  9. Possible pathways between depression, emotional and external eating. A structural equation model

    NARCIS (Netherlands)

    Ouwens, M.A.; Strien, T. van; Leeuwe, J.F.J. van

    2009-01-01

    Emotional and external eating appear to co-occur and both have been shown to correlate to neuroticism, especially depression. However, there is evidence suggesting that emotional and external eating are independent constructs. In this study we revisited the relation between depression, emotional,

  10. Synthetic digital radiographs using exposure computer models of Voxels / EGS4 Phantoms

    International Nuclear Information System (INIS)

    Kenned, Roberto; Vieira, Jose W.; Lima, Fernando R.A.; Loureiro, Eduardo

    2008-01-01

    The objective of this work is to produce synthetic digital radiographs from synthetic phantoms with the use of a Computational Model of Exposition (MCE). The literature explains a model consisted on a phantom, a Monte Carlo code and an algorithm of a radioactive source. In this work it was used the FAX phantom (Female Adult voXel), besides the EGS4 system code Eletron Shower-range version 4) and an external source, similar to that used in diagnostic radiology. The implementation of MCE creates files with information on external energy deposited in the voxels of fantoma used, here called EnergiaPorVoxel.dat. These files along with the targeted phantom (fax.sgi) worked as data entry for the DIP software (Digital Imaging Processing) to build the synthetic phantoms based on energy and the effective dose. This way you can save each slice that is the stack of pictures of these phantoms synthetics, which have been called synthetic digital radiography. Using this, it is possible to use techniques of emphasis in space to increase the contrast or elineate contours between organs and tissues. The practical use of these images is not only to allow a planning of examinations performed in clinics and hospitals and reducing unnecessary exposure to patients by error of radiographic techniques. (author)

  11. Dynamical symmetry restoration for a higher-derivative four-fermion model in an external electromagnetic field

    International Nuclear Information System (INIS)

    Elizalde, E.; Gavrilov, S.P.; Shil'nov, Yu.I.

    2000-01-01

    A four-fermion model with additional higher-derivative terms is investigated in an external electromagnetic field. The effective potential in the leading order of large-N expansion is calculated in external constant magnetic and electric fields. It is shown that, in contrast to the former results concerning the universal character of 'magnetic catalysis' in dynamical symmetry breaking, in the present higher-derivative model the magnetic field restores chiral symmetry broken initially on the tree level. Numerical results describing a second-order phase transition that accompanies the symmetry restoration at the quantum level are presented. (author)

  12. Second cancer incidence risk estimates using BEIR VII models for standard and complex external beam radiotherapy for early breast cancer

    Energy Technology Data Exchange (ETDEWEB)

    Donovan, E. M.; James, H.; Bonora, M.; Yarnold, J. R.; Evans, P. M. [Joint Department of Physics, Royal Marsden NHS Foundation Trust and Institute of Cancer Research, Sutton SM2 5PT (United Kingdom); Physics Department, Ipswich Hospital NHS Foundation Trust, Ipswich IP4 5PD (United Kingdom); Department of Academic Radiotherapy, Institute of Cancer Research and Royal Marsden NHS Foundation Trust, Sutton SM2 5PT, United Kingdom and School of Radiotherapy, University of Milan, Milan 20122 (Italy); Department of Academic Radiotherapy, Institute of Cancer Research and Royal Marsden NHS Foundation Trust, Sutton SM2 5PT (United Kingdom); Centre for Vision Speech and Signal Processing, University of Surrey, Guildford GU2 7XH (United Kingdom)

    2012-10-15

    Purpose: To compare organ specific cancer incidence risks for standard and complex external beam radiotherapy (including cone beam CT verification) following breast conservation surgery for early breast cancer.Method: Doses from breast radiotherapy and kilovoltage cone beam CT (CBCT) exposures were obtained from thermoluminescent dosimeter measurements in an anthropomorphic phantom in which the positions of radiosensitive organs were delineated. Five treatment deliveries were investigated: (i) conventional tangential field whole breast radiotherapy (WBRT), (ii) noncoplanar conformal delivery applicable to accelerated partial beast irradiation (APBI), (iii) two-volume simultaneous integrated boost (SIB) treatment, (iv) forward planned three-volume SIB, and (v) inverse-planned three volume SIB. Conformal and intensity modulated radiotherapy methods were used to plan the complex treatments. Techniques spanned the range from simple methods appropriate for patient cohorts with a low cancer recurrence risk to complex plans relevant to cohorts with high recurrence risk. Delineated organs at risk included brain, salivary glands, thyroid, contralateral breast, left and right lung, esophagus, stomach, liver, colon, and bladder. Biological Effects of Ionizing Radiation (BEIR) VII cancer incidence models were applied to the measured mean organ doses to determine lifetime attributable risk (LAR) for ages at exposure from 35 to 80 yr according to radiotherapy techniques, and included dose from the CBCT imaging. Results: All LAR decreased with age at exposure and were lowest for brain, thyroid, liver, and bladder (<0.1%). There was little dependence of LAR on radiotherapy technique for these organs and for colon and stomach. LAR values for the lungs for the three SIB techniques were two to three times those from WBRT and APBI. Uncertainties in the LAR models outweigh any differences in lung LAR between the SIB methods. Constraints in the planning of the SIB methods ensured that

  13. Integration of anatomical and external response mappings explains crossing effects in tactile localization: A probabilistic modeling approach.

    Science.gov (United States)

    Badde, Stephanie; Heed, Tobias; Röder, Brigitte

    2016-04-01

    To act upon a tactile stimulus its original skin-based, anatomical spatial code has to be transformed into an external, posture-dependent reference frame, a process known as tactile remapping. When the limbs are crossed, anatomical and external location codes are in conflict, leading to a decline in tactile localization accuracy. It is unknown whether this impairment originates from the integration of the resulting external localization response with the original, anatomical one or from a failure of tactile remapping in crossed postures. We fitted probabilistic models based on these diverging accounts to the data from three tactile localization experiments. Hand crossing disturbed tactile left-right location choices in all experiments. Furthermore, the size of these crossing effects was modulated by stimulus configuration and task instructions. The best model accounted for these results by integration of the external response mapping with the original, anatomical one, while applying identical integration weights for uncrossed and crossed postures. Thus, the model explained the data without assuming failures of remapping. Moreover, performance differences across tasks were accounted for by non-individual parameter adjustments, indicating that individual participants' task adaptation results from one common functional mechanism. These results suggest that remapping is an automatic and accurate process, and that the observed localization impairments in touch result from a cognitively controlled integration process that combines anatomically and externally coded responses.

  14. Development and external validation of a risk-prediction model to predict 5-year overall survival in advanced larynx cancer.

    Science.gov (United States)

    Petersen, Japke F; Stuiver, Martijn M; Timmermans, Adriana J; Chen, Amy; Zhang, Hongzhen; O'Neill, James P; Deady, Sandra; Vander Poorten, Vincent; Meulemans, Jeroen; Wennerberg, Johan; Skroder, Carl; Day, Andrew T; Koch, Wayne; van den Brekel, Michiel W M

    2018-05-01

    TNM-classification inadequately estimates patient-specific overall survival (OS). We aimed to improve this by developing a risk-prediction model for patients with advanced larynx cancer. Cohort study. We developed a risk prediction model to estimate the 5-year OS rate based on a cohort of 3,442 patients with T3T4N0N+M0 larynx cancer. The model was internally validated using bootstrapping samples and externally validated on patient data from five external centers (n = 770). The main outcome was performance of the model as tested by discrimination, calibration, and the ability to distinguish risk groups based on tertiles from the derivation dataset. The model performance was compared to a model based on T and N classification only. We included age, gender, T and N classification, and subsite as prognostic variables in the standard model. After external validation, the standard model had a significantly better fit than a model based on T and N classification alone (C statistic, 0.59 vs. 0.55, P statistic to 0.68. A risk prediction model for patients with advanced larynx cancer, consisting of readily available clinical variables, gives more accurate estimations of the estimated 5-year survival rate when compared to a model based on T and N classification alone. 2c. Laryngoscope, 128:1140-1145, 2018. © 2017 The American Laryngological, Rhinological and Otological Society, Inc.

  15. Predictive modeling of terrestrial radiation exposure from geologic materials

    Science.gov (United States)

    Haber, Daniel A.

    Aerial gamma ray surveys are an important tool for national security, scientific, and industrial interests in determining locations of both anthropogenic and natural sources of radioactivity. There is a relationship between radioactivity and geology and in the past this relationship has been used to predict geology from an aerial survey. The purpose of this project is to develop a method to predict the radiologic exposure rate of the geologic materials in an area by creating a model using geologic data, images from the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER), geochemical data, and pre-existing low spatial resolution aerial surveys from the National Uranium Resource Evaluation (NURE) Survey. Using these data, geospatial areas, referred to as background radiation units, homogenous in terms of K, U, and Th are defined and the gamma ray exposure rate is predicted. The prediction is compared to data collected via detailed aerial survey by our partner National Security Technologies, LLC (NSTec), allowing for the refinement of the technique. High resolution radiation exposure rate models have been developed for two study areas in Southern Nevada that include the alluvium on the western shore of Lake Mohave, and Government Wash north of Lake Mead; both of these areas are arid with little soil moisture and vegetation. We determined that by using geologic units to define radiation background units of exposed bedrock and ASTER visualizations to subdivide radiation background units of alluvium, regions of homogeneous geochemistry can be defined allowing for the exposure rate to be predicted. Soil and rock samples have been collected at Government Wash and Lake Mohave as well as a third site near Cameron, Arizona. K, U, and Th concentrations of these samples have been determined using inductively coupled mass spectrometry (ICP-MS) and laboratory counting using radiation detection equipment. In addition, many sample locations also have

  16. Predictive Models and Tools for Screening Chemicals under TSCA: Consumer Exposure Models 1.5

    Science.gov (United States)

    CEM contains a combination of models and default parameters which are used to estimate inhalation, dermal, and oral exposures to consumer products and articles for a wide variety of product and article use categories.

  17. Inhalation Exposure Input Parameters for the Biosphere Model

    Energy Technology Data Exchange (ETDEWEB)

    K. Rautenstrauch

    2004-09-10

    This analysis is one of 10 reports that support the Environmental Radiation Model for Yucca Mountain, Nevada (ERMYN) biosphere model. The ''Biosphere Model Report'' (BSC 2004 [DIRS 169460]) describes in detail the conceptual model as well as the mathematical model and its input parameters. This report documents development of input parameters for the biosphere model that are related to atmospheric mass loading and supports the use of the model to develop biosphere dose conversion factors (BDCFs). The biosphere model is one of a series of process models supporting the total system performance assessment (TSPA) for a Yucca Mountain repository. Inhalation Exposure Input Parameters for the Biosphere Model is one of five reports that develop input parameters for the biosphere model. A graphical representation of the documentation hierarchy for the ERMYN is presented in Figure 1-1. This figure shows the interrelationships among the products (i.e., analysis and model reports) developed for biosphere modeling, and the plan for development of the biosphere abstraction products for TSPA, as identified in the Technical Work Plan for Biosphere Modeling and Expert Support (BSC 2004 [DIRS 169573]). This analysis report defines and justifies values of mass loading for the biosphere model. Mass loading is the total mass concentration of resuspended particles (e.g., dust, ash) in a volume of air. Mass loading values are used in the air submodel of ERMYN to calculate concentrations of radionuclides in air inhaled by a receptor and concentrations in air surrounding crops. Concentrations in air to which the receptor is exposed are then used in the inhalation submodel to calculate the dose contribution to the receptor from inhalation of contaminated airborne particles. Concentrations in air surrounding plants are used in the plant submodel to calculate the concentrations of radionuclides in foodstuffs contributed from uptake by foliar interception.

  18. Inhalation Exposure Input Parameters for the Biosphere Model

    International Nuclear Information System (INIS)

    K. Rautenstrauch

    2004-01-01

    This analysis is one of 10 reports that support the Environmental Radiation Model for Yucca Mountain, Nevada (ERMYN) biosphere model. The ''Biosphere Model Report'' (BSC 2004 [DIRS 169460]) describes in detail the conceptual model as well as the mathematical model and its input parameters. This report documents development of input parameters for the biosphere model that are related to atmospheric mass loading and supports the use of the model to develop biosphere dose conversion factors (BDCFs). The biosphere model is one of a series of process models supporting the total system performance assessment (TSPA) for a Yucca Mountain repository. Inhalation Exposure Input Parameters for the Biosphere Model is one of five reports that develop input parameters for the biosphere model. A graphical representation of the documentation hierarchy for the ERMYN is presented in Figure 1-1. This figure shows the interrelationships among the products (i.e., analysis and model reports) developed for biosphere modeling, and the plan for development of the biosphere abstraction products for TSPA, as identified in the Technical Work Plan for Biosphere Modeling and Expert Support (BSC 2004 [DIRS 169573]). This analysis report defines and justifies values of mass loading for the biosphere model. Mass loading is the total mass concentration of resuspended particles (e.g., dust, ash) in a volume of air. Mass loading values are used in the air submodel of ERMYN to calculate concentrations of radionuclides in air inhaled by a receptor and concentrations in air surrounding crops. Concentrations in air to which the receptor is exposed are then used in the inhalation submodel to calculate the dose contribution to the receptor from inhalation of contaminated airborne particles. Concentrations in air surrounding plants are used in the plant submodel to calculate the concentrations of radionuclides in foodstuffs contributed from uptake by foliar interception

  19. Assessment of externalities related to global and local air pollutants with the NEEDS-TIMES Italy model

    Energy Technology Data Exchange (ETDEWEB)

    Pietrapertosa, F.; Cosmi, C.; Loperte, S.; Salvia, M.; Cuomo, V. [National Research Council, Institute of Methodologies for Environmental Analysis, C.da S. Loja, I-85050 Tito Scalo (PZ) (Italy); Di Leo, S. [University of Basilicata, Dept. of Environmental Engineering and Physics, C.da Macchia Romana, I-85100 Potenza (Italy); Macchiato, M. [Federico II University, Dept. of Physical Sciences, Via Cintia, I-80126 Naples (Italy)

    2010-01-15

    This work is aimed to illustrate the potentiality of the multi-region NEEDS-TIMES modelling platform, in the economic evaluation of the environmental damages due to air pollution. In particular the effects of external costs on the least-cost optimised energy system configuration were analysed in a national case study with the NEEDS-TIMES Italy model, considering the externalities related to local and global air pollutants (NO{sub x}, SO{sub 2}, VOC, particulates and GHGs). Different scenarios were compared to emphasise the role of external costs in the achievement of strategic environmental targets. The main results obtained are discussed, focusing on the changes in energy fuel mix as well as in local air pollutants and GHG emissions, highlighting the main conclusions in terms of policy strategies. (author)

  20. Modeling emission rates and exposures from outdoor cooking

    Science.gov (United States)

    Edwards, Rufus; Princevac, Marko; Weltman, Robert; Ghasemian, Masoud; Arora, Narendra K.; Bond, Tami

    2017-09-01

    Approximately 3 billion individuals rely on solid fuels for cooking globally. For a large portion of these - an estimated 533 million - cooking is outdoors, where emissions from cookstoves pose a health risk to both cooks and other household and village members. Models that estimate emissions rates from stoves in indoor environments that would meet WHO air quality guidelines (AQG), explicitly don't account for outdoor cooking. The objectives of this paper are to link health based exposure guidelines with emissions from outdoor cookstoves, using a Monte Carlo simulation of cooking times from Haryana India coupled with inverse Gaussian dispersion models. Mean emission rates for outdoor cooking that would result in incremental increases in personal exposure equivalent to the WHO AQG during a 24-h period were 126 ± 13 mg/min for cooking while squatting and 99 ± 10 mg/min while standing. Emission rates modeled for outdoor cooking are substantially higher than emission rates for indoor cooking to meet AQG, because the models estimate impact of emissions on personal exposure concentrations rather than microenvironment concentrations, and because the smoke disperses more readily outdoors compared to indoor environments. As a result, many more stoves including the best performing solid-fuel biomass stoves would meet AQG when cooking outdoors, but may also result in substantial localized neighborhood pollution depending on housing density. Inclusion of the neighborhood impact of pollution should be addressed more formally both in guidelines on emissions rates from stoves that would be protective of health, and also in wider health impact evaluation efforts and burden of disease estimates. Emissions guidelines should better represent the different contexts in which stoves are being used, especially because in these contexts the best performing solid fuel stoves have the potential to provide significant benefits.

  1. Second cancer incidence risk estimates using BEIR VII models for standard and complex external beam radiotherapy for early breast cancer

    International Nuclear Information System (INIS)

    Donovan, E. M.; James, H.; Bonora, M.; Yarnold, J. R.; Evans, P. M.

    2012-01-01

    Purpose: To compare organ specific cancer incidence risks for standard and complex external beam radiotherapy (including cone beam CT verification) following breast conservation surgery for early breast cancer.Method: Doses from breast radiotherapy and kilovoltage cone beam CT (CBCT) exposures were obtained from thermoluminescent dosimeter measurements in an anthropomorphic phantom in which the positions of radiosensitive organs were delineated. Five treatment deliveries were investigated: (i) conventional tangential field whole breast radiotherapy (WBRT), (ii) noncoplanar conformal delivery applicable to accelerated partial beast irradiation (APBI), (iii) two-volume simultaneous integrated boost (SIB) treatment, (iv) forward planned three-volume SIB, and (v) inverse-planned three volume SIB. Conformal and intensity modulated radiotherapy methods were used to plan the complex treatments. Techniques spanned the range from simple methods appropriate for patient cohorts with a low cancer recurrence risk to complex plans relevant to cohorts with high recurrence risk. Delineated organs at risk included brain, salivary glands, thyroid, contralateral breast, left and right lung, esophagus, stomach, liver, colon, and bladder. Biological Effects of Ionizing Radiation (BEIR) VII cancer incidence models were applied to the measured mean organ doses to determine lifetime attributable risk (LAR) for ages at exposure from 35 to 80 yr according to radiotherapy techniques, and included dose from the CBCT imaging. Results: All LAR decreased with age at exposure and were lowest for brain, thyroid, liver, and bladder (<0.1%). There was little dependence of LAR on radiotherapy technique for these organs and for colon and stomach. LAR values for the lungs for the three SIB techniques were two to three times those from WBRT and APBI. Uncertainties in the LAR models outweigh any differences in lung LAR between the SIB methods. Constraints in the planning of the SIB methods ensured that

  2. Numerical model and investigations of the externally heated valve Joule engine

    Energy Technology Data Exchange (ETDEWEB)

    Wojewoda, Jerzy [University of Aberdeen, School of Engineering, Fraser Noble Bldg, Aberdeen AB24 3UE (United Kingdom); Kazimierski, Zbyszko [Technical University of Lodz, Institute of Turbomachinery, 219/223 Wolczanska Str., 93-005 Lodz (Poland)

    2010-05-15

    The mineral fuels used recently, i.e., oil and gas, will be soon exploited out. This paper presents an idea of the engine where any fuel or solar heat can be used as a source of energy. The proposed model is an externally heated, 2-stroke, valve engine (EHVE). This is a piston-type engine, entirely different from the well-known Stirling one, which is the best known example of such a solution. It works in a closed Joule cycle and is designed to produce a moderate amount of energy. The engine is composed of typical parts met in piston designs: an expander, a compressor, a heater, a cooler and, additionally, two recirculation blowers, which consume a small amount of produced power. An additional advantage is its working medium, which may be simply atmospheric air and the engine has a conventional crankshaft and an oil lubrication system. It has already been proven that operation of the EHVE is possible with satisfactory power and efficiency at the output. Comparisons of the EHVE action with and without recirculation blowers are performed. (author)

  3. Modelling of a diode laser with a resonant grating of quantum wells and an external mirror

    International Nuclear Information System (INIS)

    Vysotskii, D V; Elkin, N N; Napartovich, A P; Kozlovskii, Vladimir I; Lavrushin, B M

    2011-01-01

    A three-dimensional numerical model of a diode laser with a resonant grating of quantum wells (QWs) and an external mirror is developed and used to calculate diode laser pulses that are long compared to the time of reaching a stationary regime and are short enough to neglect heating of the medium. The consistent solutions of the Helmholtz field equation and the system of diffusion equations for inversion in each QW are found. A source of charge carriers can be both an electron beam and a pump laser beam. The calculations yielded the longitudinal and radial profiles of the generated field, as well as its wavelength and power. The effective threshold pump current is determined. In the created iteration algorithm, the calculation time linearly increases with the number of QWs, which allows one to find the characteristics of lasers with a large number of QWs. The output powers and beam divergence angles of a cylindrical laser are calculated for different cavity lengths and pump spot radii. After calculating the fundamental mode characteristics, high-order modes were additionally calculated on the background of the frozen carrier distributions in the QW grating. It is shown that all the competing modes remain below the excitation threshold for the pump powers used in the experiment. The calculated and experimental data for the case of pumping by a nanosecond electron beam are qualitatively compared.

  4. Skeletal dosimetry for external exposures to photons based on {mu}CT images of spongiosa: Consideration of voxel resolution, cluster size, and medullary bone surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Kramer, R.; Khoury, H. J.; Vieira, J. W.; Brown, K. A. Robson [Departamento de Energia Nuclear, Universidade Federal de Pernambuco, Avenida Professor Luiz Freire 1000, Cidade Universitaria, CEP 50740-540, Recife, Pernambuco (Brazil); Centro Federal de Educacao Tecnologica de Pernambuco, Avenida Professor Luiz Freire 500, CEP 50740-540, Recife, Pernambuco, Brazil and Escola Politecnica, UPE, Rua Benfica 455, CEP 50751-460, Recife, Pernambuco (Brazil); Imaging Laboratory, Department of Archaeology and Anthropology, University of Bristol, 43 Woodland Road, Bristol BS8 1UU (United Kingdom)

    2009-11-15

    Skeletal dosimetry based on {mu}CT images of trabecular bone has recently been introduced to calculate the red bone marrow (RBM) and the bone surface cell (BSC) equivalent doses in human phantoms for external exposure to photons. In order to use the {mu}CT images for skeletal dosimetry, spongiosa voxels in the skeletons were replaced at run time by so-called micromatrices, which have exactly the size of a spongiosa voxel and contain segmented trabecular bone and marrow microvoxels. A cluster (=parallelepiped) of 2x2x2=8 micromatrices was used systematically and periodically throughout the spongiosa volume during the radiation transport calculation. Systematic means that when a particle leaves a spongiosa voxel to enter into a neighboring spongiosa voxel, then the next micromatrix in the cluster will be used. Periodical means that if the particle travels through more than two spongiosa voxels in a row, then the cluster will be repeated. Based on the bone samples available at the time, clusters of up to 3x3x3=27 micromatrices were studied. While for a given trabecular bone volume fraction the whole-body RBM equivalent dose showed converging results for cluster sizes between 8 and 27 micromatrices, this was not the case for the BSC equivalent dose. The BSC equivalent dose seemed to be very sensitive to the number, form, and thickness of the trabeculae. In addition, the cluster size and/or the microvoxel resolution were considered to be possible causes for the differences observed. In order to resolve this problem, this study used a bone sample large enough to extract clusters containing up to 8x8x8=512 micromatrices and which was scanned with two different voxel resolutions. Taking into account a recent proposal, this investigation also calculated the BSC equivalent dose on medullary surfaces of cortical bone in the arm and leg bones. The results showed (1) that different voxel resolutions have no effect on the RBM equivalent dose but do influence the BSC equivalent

  5. Internalisation of external cost in the power generation sector: Analysis with Global Multi-regional MARKAL model

    International Nuclear Information System (INIS)

    Rafaj, Peter; Kypreos, Socrates

    2007-01-01

    The Global MARKAL-Model (GMM), a multi-regional 'bottom-up' partial equilibrium model of the global energy system with endogenous technological learning, is used to address impacts of internalisation of external costs from power production. This modelling approach imposes additional charges on electricity generation, which reflect the costs of environmental and health damages from local pollutants (SO 2 , NO x ) and climate change, wastes, occupational health, risk of accidents, noise and other burdens. Technologies allowing abatement of pollutants emitted from power plants are rapidly introduced into the energy system, for example, desulphurisation, NO x removal, and CO 2 scrubbers. The modelling results indicate substantial changes in the electricity production system in favour of natural gas combined cycle, nuclear power and renewables induced by internalisation of external costs and also efficiency loss due to the use of scrubbers. Structural changes and fuel switching in the electricity sector result in significant reduction of emissions of both local pollution and CO 2 over the modelled time period. Strong decarbonisation impact of internalising local externalities suggests that ancillary benefits can be expected from policies directly addressing other issues then CO 2 mitigation. Finally, the detailed analysis of the total generation cost of different technologies points out that inclusion of external cost in the price of electricity increases competitiveness of non-fossil generation sources and fossil power plants with emission control

  6. Minimising negative externalities cost using 0-1 mixed integer linear programming model in e-commerce environment

    Directory of Open Access Journals (Sweden)

    Akyene Tetteh

    2017-04-01

    Full Text Available Background: Although the Internet boosts business profitability, without certain activities like efficient transportation, scheduling, products ordered via the Internet may reach their destination very late. The environmental problems (vehicle part disposal, carbon monoxide [CO], nitrogen oxide [NOx] and hydrocarbons [HC] associated with transportation are mostly not accounted for by industries. Objectives: The main objective of this article is to minimising negative externalities cost in e-commerce environments. Method: The 0-1 mixed integer linear programming (0-1 MILP model was used to model the problem statement. The result was further analysed using the externality percentage impact factor (EPIF. Results: The simulation results suggest that (1 The mode of ordering refined petroleum products does not impact on the cost of distribution, (2 an increase in private cost is directly proportional to the externality cost, (3 externality cost is largely controlled by the government and number of vehicles used in the distribution and this is in no way influenced by the mode of request (i.e. Internet or otherwise and (4 externality cost may be reduce by using more ecofriendly fuel system.

  7. Lyssavirus infection: 'low dose, multiple exposure' in the mouse model.

    Science.gov (United States)

    Banyard, Ashley C; Healy, Derek M; Brookes, Sharon M; Voller, Katja; Hicks, Daniel J; Núñez, Alejandro; Fooks, Anthony R

    2014-03-06

    The European bat lyssaviruses (EBLV-1 and EBLV-2) are zoonotic pathogens present within bat populations across Europe. The maintenance and transmission of lyssaviruses within bat colonies is poorly understood. Cases of repeated isolation of lyssaviruses from bat roosts have raised questions regarding the maintenance and intraspecies transmissibility of these viruses within colonies. Furthermore, the significance of seropositive bats in colonies remains unclear. Due to the protected nature of European bat species, and hence restrictions to working with the natural host for lyssaviruses, this study analysed the outcome following repeat inoculation of low doses of lyssaviruses in a murine model. A standardized dose of virus, EBLV-1, EBLV-2 or a 'street strain' of rabies (RABV), was administered via a peripheral route to attempt to mimic what is hypothesized as natural infection. Each mouse (n=10/virus/group/dilution) received four inoculations, two doses in each footpad over a period of four months, alternating footpad with each inoculation. Mice were tail bled between inoculations to evaluate antibody responses to infection. Mice succumbed to infection after each inoculation with 26.6% of mice developing clinical disease following the initial exposure across all dilutions (RABV, 32.5% (n=13/40); EBLV-1, 35% (n=13/40); EBLV-2, 12.5% (n=5/40)). Interestingly, the lowest dose caused clinical disease in some mice upon first exposure ((RABV, 20% (n=2/10) after first inoculation; RABV, 12.5% (n=1/8) after second inoculation; EBLV-2, 10% (n=1/10) after primary inoculation). Furthermore, five mice developed clinical disease following the second exposure to live virus (RABV, n=1; EBLV-1, n=1; EBLV-2, n=3) although histopathological examination indicated that the primary inoculation was the most probably cause of death due to levels of inflammation and virus antigen distribution observed. All the remaining mice (RABV, n=26; EBLV-1, n=26; EBLV-2, n=29) survived the tertiary and

  8. Symptoms of internalizing and externalizing problems: modeling recovery curves after the death of a parent.

    Science.gov (United States)

    Schmiege, Sarah J; Khoo, Siek Toon; Sandler, Irwin N; Ayers, Tim S; Wolchik, Sharlene A

    2006-12-01

    The death of a parent is a major family disruption that can place children at risk for later depression and other mental health problems. Theoretically based randomized controlled trial for parentally bereaved children. Two-hundred and forty-four children and adolescents and their caregivers from 156 families were randomly assigned to the Family Bereavement Program (FBP) intervention condition (90 families; 135 children) or to a control condition (66 families; 109 children). Data collection occurred from 1996 to 1998. Children and caregivers in the intervention condition met separately for 12 two-hour weekly sessions. Skills targeted by the program for children included positive coping, stress appraisals, control beliefs, and self-esteem. The caregiver program targeted caregiver mental health, life stressors, and improved discipline in the home. Both child and caregiver programs focused on improved quality of the caregiver-child relationship. Child and caregiver reports of internalizing and externalizing symptoms. Longitudinal growth curve modeling was performed to model symptoms over time from the point of parental death. The rate of recovery for girls in the program condition was significantly different from that of girls in the control condition across all outcomes. Boys in both conditions showed reduced symptoms over time. The methodology offers a conceptually unique way of assessing recovery in terms of reduced mental health problems over time after an event and has contributed to further understanding of FBP intervention effects. The intervention program facilitated recovery among girls, who did not show reduction in behavior problems without the program, while boys demonstrated decreased symptoms even without intervention.

  9. Evolution of star systems supplied by external stars: a model for Galaxy nuclei

    International Nuclear Information System (INIS)

    Dokuchaev, V.I.; Ozernoj, L.M.; AN SSSR, Moscow. Inst. Yadernykh Issledovanij)

    1985-01-01

    Extended rarefied environments around the core of a non-isothermic galaxy nucleus can supply the core by both energies and masses of external stars due to relaxation mechanisms. These factors can influence considerably the secular evolution of the core when competing with usual star evaporation from it. Conditions are found under which external environments influence the core evolution much more than star evaporation. This results in expansion of the core instead of its collapse

  10. Local and global bifurcations in an economic growth model with endogenous labour supply and multiplicative external habits

    Science.gov (United States)

    Gori, Luca; Sodini, Mauro

    2014-03-01

    This paper analyses the mathematical properties of an economic growth model with overlapping generations, endogenous labour supply, and multiplicative external habits. The dynamics of the economy is characterised by a two-dimensional map describing the time evolution of capital and labour supply. We show that if the relative importance of external habits in the utility function is sufficiently high, multiple (determinate or indeterminate) fixed points and poverty traps can exist. In addition, periodic or quasiperiodic behaviour and/or coexistence of attractors may occur.

  11. SHEDS-HT: An Integrated Probabilistic Exposure Model for Prioritizing Exposures to Chemicals with Near-Field and Dietary Sources

    Science.gov (United States)

    United States Environmental Protection Agency (USEPA) researchers are developing a strategy for highthroughput (HT) exposure-based prioritization of chemicals under the ExpoCast program. These novel modeling approaches for evaluating chemicals based on their potential for biologi...

  12. High Throughput Exposure Modeling of Semi-Volatile Chemicals in Articles of Commerce (ACS)

    Science.gov (United States)

    Risk due to chemical exposure is a function of both chemical hazard and exposure. Near-field exposures to chemicals in consumer products are identified as the main drivers of exposure and yet are not well quantified or understood. The ExpoCast project is developing a model that e...

  13. External exposure from airborne radionuclides

    International Nuclear Information System (INIS)

    Le Grand, J.; Roux, Y.

    1991-01-01

    Shielding factors have been calculated by the point kernel method by Riso National Laboratory for indoor residences in selected European single-family and multistory houses and outdoor residences in built-up urban areas. Parametric variations (thickness of outer and inner walls, floors and roofs) have been performed to identify the most important factors responsible for affording protection indoors against plume gamma radiation. Recommendations have been made for representative shielding factors. G S F considers three types of buildings: a house of prefabricated parts, a two storey semi-detached house, and a houseblock in two different urban surroundings. The calculations were performed using the Monte Carlo photon transport code SAM-CE. Shielding factors are calculated for the living rooms, basements and outside locations of the buildings. In France a representative sample of about twenty dwellings is defined in each of the 31 French 'departements' where a survey on housing characteristics has been conducted. Using Monte-Carlo techniques the shielding factors are calculated in these houses. The shielding factor distribution for a radionuclide is summarized in each 'departement' by a conservative average and by the two extreme values: the worst shielded apartment and the best one's. Furthermore two experimental campaigns have been made to validate the computer codes. These results are discussed not only according to the respective calculation method, but also to the considered housing characteristics. The differences which come from the methods are not negligible, but they are small compared to those which come from the housing characteristics. For similar main house parameters, a relatively good agreement between the results from the different calculation methods is found

  14. Indicators of residential traffic exposure: Modelled NOX, traffic proximity, and self-reported exposure in RHINE III

    Science.gov (United States)

    Carlsen, Hanne Krage; Bäck, Erik; Eneroth, Kristina; Gislason, Thorarinn; Holm, Mathias; Janson, Christer; Jensen, Steen Solvang; Johannessen, Ane; Kaasik, Marko; Modig, Lars; Segersson, David; Sigsgaard, Torben; Forsberg, Bertil; Olsson, David; Orru, Hans

    2017-10-01

    Few studies have investigated associations between self-reported and modelled exposure to traffic pollution. The objective of this study was to examine correlations between self-reported traffic exposure and modelled (a) NOX and (b) traffic proximity in seven different northern European cities; Aarhus (Denmark), Bergen (Norway), Gothenburg, Umeå, and Uppsala (Sweden), Reykjavik (Iceland), and Tartu (Estonia). We analysed data from the RHINE III (Respiratory Health in Northern Europe, http://www.rhine.nu)

  15. External validation of a normal tissue complication probability model for radiation-induced hypothyroidism in an independent cohort

    DEFF Research Database (Denmark)

    Rønjom, Marianne F; Brink, Carsten; Bentzen, Søren M

    2015-01-01

    blood tests in the validation cohort relative to the original cohort. However, Pearson's correlation coefficients between model and clinical outcome were high: r = 0.97 estimated by the original model versus the original cohort, and r = 0.97 estimated by the original model versus the new cohort....... CONCLUSION: Dmean and Vthyroid were significant predictors of RIHT in both cohorts. The original NTCP model demonstrated external validity owing to high Pearson's correlation coefficients between estimated and observed incidence rates of RIHT in the original as well as in the validation cohort. This model...

  16. Population modelling to compare chronic external radiotoxicity between individual and population endpoints in four taxonomic groups.

    Science.gov (United States)

    Alonzo, Frédéric; Hertel-Aas, Turid; Real, Almudena; Lance, Emilie; Garcia-Sanchez, Laurent; Bradshaw, Clare; Vives I Batlle, Jordi; Oughton, Deborah H; Garnier-Laplace, Jacqueline

    2016-02-01

    In this study, we modelled population responses to chronic external gamma radiation in 12 laboratory species (including aquatic and soil invertebrates, fish and terrestrial mammals). Our aim was to compare radiosensitivity between individual and population endpoints and to examine how internationally proposed benchmarks for environmental radioprotection protected species against various risks at the population level. To do so, we used population matrix models, combining life history and chronic radiotoxicity data (derived from laboratory experiments and described in the literature and the FREDERICA database) to simulate changes in population endpoints (net reproductive rate R0, asymptotic population growth rate λ, equilibrium population size Neq) for a range of dose rates. Elasticity analyses of models showed that population responses differed depending on the affected individual endpoint (juvenile or adult survival, delay in maturity or reduction in fecundity), the considered population endpoint (R0, λ or Neq) and the life history of the studied species. Among population endpoints, net reproductive rate R0 showed the lowest EDR10 (effective dose rate inducing 10% effect) in all species, with values ranging from 26 μGy h(-1) in the mouse Mus musculus to 38,000 μGy h(-1) in the fish Oryzias latipes. For several species, EDR10 for population endpoints were lower than the lowest EDR10 for individual endpoints. Various population level risks, differing in severity for the population, were investigated. Population extinction (predicted when radiation effects caused population growth rate λ to decrease below 1, indicating that no population growth in the long term) was predicted for dose rates ranging from 2700 μGy h(-1) in fish to 12,000 μGy h(-1) in soil invertebrates. A milder risk, that population growth rate λ will be reduced by 10% of the reduction causing extinction, was predicted for dose rates ranging from 24 μGy h(-1) in mammals to 1800 μGy h(-1) in

  17. Inhalation Exposure Input Parameters for the Biosphere Model

    Energy Technology Data Exchange (ETDEWEB)

    M. A. Wasiolek

    2003-09-24

    This analysis is one of the nine reports that support the Environmental Radiation Model for Yucca Mountain Nevada (ERMYN) biosphere model. The ''Biosphere Model Report'' (BSC 2003a) describes in detail the conceptual model as well as the mathematical model and its input parameters. This report documents a set of input parameters for the biosphere model, and supports the use of the model to develop biosphere dose conversion factors (BDCFs). The biosphere model is one of a series of process models supporting the Total System Performance Assessment (TSPA) for a Yucca Mountain repository. This report, ''Inhalation Exposure Input Parameters for the Biosphere Model'', is one of the five reports that develop input parameters for the biosphere model. A graphical representation of the documentation hierarchy for the ERMYN is presented in Figure 1-1. This figure shows the interrelationships among the products (i.e., analysis and model reports) developed for biosphere modeling, and the plan for development of the biosphere abstraction products for TSPA, as identified in the ''Technical Work Plan: for Biosphere Modeling and Expert Support'' (BSC 2003b). It should be noted that some documents identified in Figure 1-1 may be under development at the time this report is issued and therefore not available at that time. This figure is included to provide an understanding of how this analysis report contributes to biosphere modeling in support of the license application, and is not intended to imply that access to the listed documents is required to understand the contents of this analysis report. This analysis report defines and justifies values of mass loading, which is the total mass concentration of resuspended particles (e.g., dust, ash) in a volume of air. Measurements of mass loading are used in the air submodel of ERMYN to calculate concentrations of radionuclides in air surrounding crops and concentrations in air

  18. Inhalation Exposure Input Parameters for the Biosphere Model

    International Nuclear Information System (INIS)

    M. A. Wasiolek

    2003-01-01

    This analysis is one of the nine reports that support the Environmental Radiation Model for Yucca Mountain Nevada (ERMYN) biosphere model. The ''Biosphere Model Report'' (BSC 2003a) describes in detail the conceptual model as well as the mathematical model and its input parameters. This report documents a set of input parameters for the biosphere model, and supports the use of the model to develop biosphere dose conversion factors (BDCFs)