Radionuclide identification algorithm for organic scintillator-based radiation portal monitor
NASA Astrophysics Data System (ADS)
Paff, Marc Gerrit; Di Fulvio, Angela; Clarke, Shaun D.; Pozzi, Sara A.
2017-03-01
We have developed an algorithm for on-the-fly radionuclide identification for radiation portal monitors using organic scintillation detectors. The algorithm was demonstrated on experimental data acquired with our pedestrian portal monitor on moving special nuclear material and industrial sources at a purpose-built radiation portal monitor testing facility. The experimental data also included common medical isotopes. The algorithm takes the power spectral density of the cumulative distribution function of the measured pulse height distributions and matches these to reference spectra using a spectral angle mapper. F-score analysis showed that the new algorithm exhibited significant performance improvements over previously implemented radionuclide identification algorithms for organic scintillators. Reliable on-the-fly radionuclide identification would help portal monitor operators more effectively screen out the hundreds of thousands of nuisance alarms they encounter annually due to recent nuclear-medicine patients and cargo containing naturally occurring radioactive material. Portal monitor operators could instead focus on the rare but potentially high impact incidents of nuclear and radiological material smuggling detection for which portal monitors are intended.
NASA Astrophysics Data System (ADS)
Van Uffelen, Marco; Berghmans, Francis; Brichard, Benoit; Borgermans, Paul; Decréton, Marc C.
2002-09-01
Optical fibers stimulate much interest since many years for their potential use in various nuclear environments, both for radiation tolerant and EMI-free data communication as well as for distributed sensing. Besides monitoring temperature and stress, measuring ionizing doses with optical fibers is particularly essential in applications such as long-term nuclear waste disposal monitoring, and for real-time aging monitoring of power and signal cables installed inside a reactor containment building. Two distinct options exist to perform optical fiber dosimetry. First, find an accurate model for a restricted application field that accounts for all the parameters that influence the radiation response of a standard fiber, or second, develop a dedicated fiber with a response that will solely depend on the deposited energy. Using various models presented in literature, we evaluate both standard commercially available and custom-made optical fibers under gamma radiation, particularly for distributed dosimetry applications with an optical time domain reflectometer (OTDR). We therefore present the radiation induced attenuation at near-infrared telecom wavelengths up to MGy total dose levels, with dose rates ranging from about 1 Gy/h up to 1 kGy/h, whereas temperature was raised step-wise from 25 °C to 85 °C. Our results allow to determine and compare the practical limitations of distributed dose measurements with both fiber types in terms of temperature sensitivity, dose estimation accuracy and spatial resolution.
Imaging and characterization of primary and secondary radiation in ion beam therapy
NASA Astrophysics Data System (ADS)
Granja, Carlos; Martisikova, Maria; Jakubek, Jan; Opalka, Lukas; Gwosch, Klaus
2016-07-01
Imaging in ion beam therapy is an essential and increasingly significant tool for treatment planning and radiation and dose deposition verification. Efforts aim at providing precise radiation field characterization and online monitoring of radiation dose distribution. A review is given of the research and methodology of quantum-imaging, composition, spectral and directional characterization of the mixed-radiation fields in proton and light ion beam therapy developed by the IEAP CTU Prague and HIT Heidelberg group. Results include non-invasive imaging of dose deposition and primary beam online monitoring.
Sample size allocation for food item radiation monitoring and safety inspection.
Seto, Mayumi; Uriu, Koichiro
2015-03-01
The objective of this study is to identify a procedure for determining sample size allocation for food radiation inspections of more than one food item to minimize the potential risk to consumers of internal radiation exposure. We consider a simplified case of food radiation monitoring and safety inspection in which a risk manager is required to monitor two food items, milk and spinach, in a contaminated area. Three protocols for food radiation monitoring with different sample size allocations were assessed by simulating random sampling and inspections of milk and spinach in a conceptual monitoring site. Distributions of (131)I and radiocesium concentrations were determined in reference to (131)I and radiocesium concentrations detected in Fukushima prefecture, Japan, for March and April 2011. The results of the simulations suggested that a protocol that allocates sample size to milk and spinach based on the estimation of (131)I and radiocesium concentrations using the apparent decay rate constants sequentially calculated from past monitoring data can most effectively minimize the potential risks of internal radiation exposure. © 2014 Society for Risk Analysis.
[Organization of monitoring of electromagnetic radiation in the urban environment].
Savel'ev, S I; Dvoeglazova, S V; Koz'min, V A; Kochkin, D E; Begishev, M R
2008-01-01
The authors describe new current approaches to monitoring the environment, including the sources of electromagnetic radiation and noise. Electronic maps of the area under study are shown to be made, by constructing the isolines or distributing the actual levels of controlled factors. These current approaches to electromagnetic and acoustic monitoring make it possible to automate a process of measurements, to analyze the established situation, and to simplify the risk controlling methodology.
Black, Marykate Z; Minchin, Peter E H; Gould, Nick; Patterson, Kevin J; Clearwater, Michael J
2012-10-01
In vivo measurements of (14)C tracer distribution have usually involved monitoring the β(-) particles produced as (14)C decays. These particles are only detectable over short distances, limiting the use of this technique to thin plant material. In the present experiments, X-ray detectors were used to monitor the Bremsstrahlung radiation emitted since β(-) particles were absorbed in plant tissues. Bremsstrahlung radiation is detectable through larger tissue depths. The aim of these experiments was to demonstrate the Bremsstrahlung method by monitoring in vivo tracer-labelled photosynthate partitioning in small kiwifruit (Actinidia arguta (Siebold & Zucc.) Planch. ex Miq.) plants in response to root pruning. A source shoot, consisting of four leaves, was pulse labelled with (14)CO(2). Detectors monitored import into a fruit and the root system, and export from a source leaf. Repeat pulse labelling enabled the comparison of pre- and post-treatment observations within an individual plant. Diurnal trends were observed in the distribution of tracer, with leaf export reduced at night. Tracer accumulated in the roots declined after approximately 48 h, which may have resulted from export of (14)C from the roots in carbon skeletons. Cutting off half the roots did not affect tracer distribution to the remaining half. Tracer distribution to the fruit was increased after root pruning, demonstrating the higher competitive strength of the fruit than the roots for carbohydrate supply. Increased partitioning to the fruit following root pruning has also been demonstrated in kiwifruit field trials.
NASA Astrophysics Data System (ADS)
Paff, Marc Gerrit; Ruch, Marc L.; Poitrasson-Riviere, Alexis; Sagadevan, Athena; Clarke, Shaun D.; Pozzi, Sara
2015-07-01
We present new experimental results from a radiation portal monitor based on the use of organic liquid scintillators. The system was tested as part of a 3He-free radiation portal monitor testing campaign at the European Commission's Joint Research Centre in Ispra, Italy, in February 2014. The radiation portal monitor was subjected to a wide range of test conditions described in ANSI N42.35, including a variety of gamma-ray sources and a 20,000 n/s 252Cf source. A false alarm test tested whether radiation portal monitors ever alarmed in the presence of only natural background. The University of Michigan Detection for Nuclear Nonproliferation Group's system triggered zero false alarms in 2739 trials. It consistently alarmed on a variety of gamma-ray sources travelling at 1.2 m/s at a 70 cm source to detector distance. The neutron source was detected at speeds up to 3 m/s and in configurations with up to 8 cm of high density polyethylene shielding. The success of on-the-fly radionuclide identification varied with the gamma-ray source measured as well as with which of two radionuclide identification methods was used. Both methods used a least squares comparison between the measured pulse height distributions to library spectra to pick the best match. The methods varied in how the pulse height distributions were modified prior to the least squares comparison. Correct identification rates were as high as 100% for highly enriched uranium, but as low as 50% for 241Am. Both radionuclide identification algorithms produced mixed results, but the concept of using liquid scintillation detectors for gamma-ray and neutron alarming in radiation portal monitor was validated.
NASA Technical Reports Server (NTRS)
Crucian, Brian E.; Morgan, Jennifer L. L.; Quiriarte, Heather A.; Sams, Clarence F.; Smith, Scott M.; Zwart, Sara R.
2012-01-01
Both radiation and increased iron stores can independently increase oxidative damage, resulting in protein, lipid and DNA oxidation. Oxidative stress increases the risk of many health problems including cancer, cataracts, and heart disease. This study, a subset of a larger interdisciplinary investigation of the combined effect of iron overload on sensitivity to radiation injury, monitored immune parameters in the peripheral blood of rats subjected to gamma radiation, high dietary iron or both. Specific immune measures consisted of: (1) peripheral leukocyte distribution, (2) plasma cytokine levels and (3) cytokine production profiles following whole blood mitogenic stimulation
NASA Astrophysics Data System (ADS)
Berger, Thomas; Burmeister, Sönke; Matthiä, Daniel; Przybyla, Bartos; Reitz, Günther; Bilski, Pawel; Hajek, Michael; Sihver, Lembit; Szabo, Julianna; Ambrozova, Iva; Vanhavere, Filip; Gaza, Ramona; Semones, Edward; Yukihara, Eduardo G.; Benton, Eric R.; Uchihori, Yukio; Kodaira, Satoshi; Kitamura, Hisashi; Boehme, Matthias
2017-03-01
The natural radiation environment in Low Earth Orbit (LEO) differs significantly in composition and energy from that found on Earth. The space radiation field consists of high energetic protons and heavier ions from Galactic Cosmic Radiation (GCR), as well as of protons and electrons trapped in the Earth's radiation belts (Van Allen belts). Protons and some heavier particles ejected in occasional Solar Particle Events (SPEs) might in addition contribute to the radiation exposure in LEO. All sources of radiation are modulated by the solar cycle. During solar maximum conditions SPEs occur more frequently with higher particle intensities. Since the radiation exposure in LEO exceeds exposure limits for radiation workers on Earth, the radiation exposure in space has been recognized as a main health concern for humans in space missions from the beginning of the space age on. Monitoring of the radiation environment is therefore an inevitable task in human spaceflight. Since mission profiles are always different and each spacecraft provides different shielding distributions, modifying the radiation environment measurements needs to be done for each mission. The experiments "Dose Distribution within the ISS (DOSIS)" (2009-2011) and "Dose Distribution within the ISS 3D (DOSIS 3D)" (2012-onwards) onboard the Columbus Laboratory of the International Space Station (ISS) use a detector suite consisting of two silicon detector telescopes (DOSimetry TELescope = DOSTEL) and passive radiation detector packages (PDP) and are designed for the determination of the temporal and spatial variation of the radiation environment. With the DOSTEL instruments' changes of the radiation composition and the related exposure levels in dependence of the solar cycle, the altitude of the ISS and the influence of attitude changes of the ISS during Space Shuttle dockings inside the Columbus Laboratory have been monitored. The absorbed doses measured at the end of May 2016 reached up to 286 μGy/day with dose equivalent values of 647 μSv/day.
DOE Office of Scientific and Technical Information (OSTI.GOV)
van Marrewijk, N.; Mirzaei, B.; Hayton, D.
2015-10-07
In this study, we have performed frequency locking of a dual, forward reverse emitting third-order distributed feedback quantum cascade laser (QCL) at 3.5 THz. By using both directions of THz emission in combination with two gas cells and two power detectors, we can for the first time perform frequency stabilization, while monitor the frequency locking quality independently. We also characterize how the use of a less sensitive pyroelectric detector can influence the quality of frequency locking, illustrating experimentally that the sensitivity of the detectors is crucial. Using both directions of terahertz (THz) radiation has a particular advantage for the applicationmore » of a QCL as a local oscillator, where radiation from one side can be used for frequency/phase stabilization, leaving the other side to be fully utilized as a local oscillator to pump a mixer.« less
Multi-directional radiation detector using photographic film
NASA Astrophysics Data System (ADS)
Junet, L. K.; Majid, Z. A. Abdul; Sapuan, A. H.; Sayed, I. S.; Pauzi, N. F.
2014-11-01
Ionising radiation has always been part of our surrounding and people are continuously exposed to it. Ionising radiation is harmful to human health, thus it is vital to monitor the radiation. To monitor radiation, there are three main points that should be observed cautiously, which are energy, quantity, and direction of the radiation sources. A three dimensional (3D) dosimeter is an example of a radiation detector that provide these three main points. This dosimeter is able to record the radiation dose distribution in 3D. Applying the concept of dose detection distribution, study has been done to design a multi-directional radiation detector of different filter thicknesses. This is obtained by designing a cylinder shaped aluminum filter with several layers of different thickness. Black and white photographic material is used as a radiation-sensitive material and a PVC material has been used as the enclosure. The device is then exposed to a radiation source with different exposure factors. For exposure factor 70 kVp, 16 mAs; the results have shown that optical density (OD) value at 135° is 1.86 higher compared with an OD value at 315° which is 0.71 as the 135° area received more radiation compare to 315° region. Furthermore, with an evidence of different angle of film give different value of OD shows that this device has a multidirectional ability. Materials used to develop this device are widely available in the market, thus reducing the cost of development and making it suitable for commercialisation.
NASA Technical Reports Server (NTRS)
Crucian, Brian E.; Morgan, Jennifer L. L.; Quiriarte, Heather A.; Sams, Clarence F.; Smith, Scott M.; Zwart, Sara R.
2011-01-01
NASA is concerned with the health risks to astronauts, particularly those risks related to radiation exposure. Both radiation and increased iron stores can independently increase oxidative damage, resulting in protein, lipid and DNA oxidation. Oxidative stress increases the risk of many health problems including cancer, cataracts, and heart disease. This study, a subset of a larger interdisciplinary investigation of the combined effect of iron overload on sensitivity to radiation injury, monitored immune parameters in the peripheral blood of rats subjected to gamma radiation, high dietary iron or both. Specific immune measures consisted of (A) peripheral leukocyte distribution; (B) plasma cytokine levels; (C) cytokine production profiles following whole blood stimulation of either T cells or monocytes.
Radiation detection and situation management by distributed sensor networks
DOE Office of Scientific and Technical Information (OSTI.GOV)
Jan, Frigo; Mielke, Angela; Cai, D Michael
Detection of radioactive materials in an urban environment usually requires large, portal-monitor-style radiation detectors. However, this may not be a practical solution in many transport scenarios. Alternatively, a distributed sensor network (DSN) could complement portal-style detection of radiological materials through the implementation of arrays of low cost, small heterogeneous sensors with the ability to detect the presence of radioactive materials in a moving vehicle over a specific region. In this paper, we report on the use of a heterogeneous, wireless, distributed sensor network for traffic monitoring in a field demonstration. Through wireless communications, the energy spectra from different radiation detectorsmore » are combined to improve the detection confidence. In addition, the DSN exploits other sensor technologies and algorithms to provide additional information about the vehicle, such as its speed, location, class (e.g. car, truck), and license plate number. The sensors are in-situ and data is processed in real-time at each node. Relevant information from each node is sent to a base station computer which is used to assess the movement of radioactive materials.« less
NASA Astrophysics Data System (ADS)
Korir, Geoffrey; Wambani, Jeska; Korir, Ian
2011-04-01
This study details the distribution and trends of doses due to occupational radiation exposure among radiation workers from participating medical institutions in Kenya, where monthly dose measurements were collected for a period of one year ranging from January to December in 2007. A total of 367 medical radiation workers were monitored using thermoluminescent dosemeters. They included radiologists (27%), oncologists (2%), dentists (4%), Physicists (5%), technologists (45%), nurses (4%), film processor technicians (3%), auxiliary staff (4%), and radiology office staff (5%). The average annual effective dose of all categories of staff was found to range from 1.19 to 2.52 mSv. This study formed the initiation stage of wider, comprehensive and more frequent monitoring of occupational radiation exposures and long-term investigations into its accumulation patterns in our country.
Some computer graphical user interfaces in radiation therapy.
Chow, James C L
2016-03-28
In this review, five graphical user interfaces (GUIs) used in radiation therapy practices and researches are introduced. They are: (1) the treatment time calculator, superficial X-ray treatment time calculator (SUPCALC) used in the superficial X-ray radiation therapy; (2) the monitor unit calculator, electron monitor unit calculator (EMUC) used in the electron radiation therapy; (3) the multileaf collimator machine file creator, sliding window intensity modulated radiotherapy (SWIMRT) used in generating fluence map for research and quality assurance in intensity modulated radiation therapy; (4) the treatment planning system, DOSCTP used in the calculation of 3D dose distribution using Monte Carlo simulation; and (5) the monitor unit calculator, photon beam monitor unit calculator (PMUC) used in photon beam radiation therapy. One common issue of these GUIs is that all user-friendly interfaces are linked to complex formulas and algorithms based on various theories, which do not have to be understood and noted by the user. In that case, user only needs to input the required information with help from graphical elements in order to produce desired results. SUPCALC is a superficial radiation treatment time calculator using the GUI technique to provide a convenient way for radiation therapist to calculate the treatment time, and keep a record for the skin cancer patient. EMUC is an electron monitor unit calculator for electron radiation therapy. Instead of doing hand calculation according to pre-determined dosimetric tables, clinical user needs only to input the required drawing of electron field in computer graphical file format, prescription dose, and beam parameters to EMUC to calculate the required monitor unit for the electron beam treatment. EMUC is based on a semi-experimental theory of sector-integration algorithm. SWIMRT is a multileaf collimator machine file creator to generate a fluence map produced by a medical linear accelerator. This machine file controls the multileaf collimator to deliver intensity modulated beams for a specific fluence map used in quality assurance or research. DOSCTP is a treatment planning system using the computed tomography images. Radiation beams (photon or electron) with different energies and field sizes produced by a linear accelerator can be placed in different positions to irradiate the tumour in the patient. DOSCTP is linked to a Monte Carlo simulation engine using the EGSnrc-based code, so that 3D dose distribution can be determined accurately for radiation therapy. Moreover, DOSCTP can be used for treatment planning of patient or small animal. PMUC is a GUI for calculation of the monitor unit based on the prescription dose of patient in photon beam radiation therapy. The calculation is based on dose corrections in changes of photon beam energy, treatment depth, field size, jaw position, beam axis, treatment distance and beam modifiers. All GUIs mentioned in this review were written either by the Microsoft Visual Basic.net or a MATLAB GUI development tool called GUIDE. In addition, all GUIs were verified and tested using measurements to ensure their accuracies were up to clinical acceptable levels for implementations.
Radiation: Physical Characterization and Environmental Measurements
NASA Technical Reports Server (NTRS)
1997-01-01
In this session, Session WP4, the discussion focuses on the following topics: Production of Neutrons from Interactions of GCR-Like Particles; Solar Particle Event Dose Distributions, Parameterization of Dose-Time Profiles; Assessment of Nuclear Events in the Body Produced by Neutrons and High-Energy Charged Particles; Ground-Based Simulations of Cosmic Ray Heavy Ion Interactions in Spacecraft and Planetary Habitat Shielding Materials; Radiation Measurements in Space Missions; Radiation Measurements in Civil Aircraft; Analysis of the Pre-Flight and Post-Flight Calibration Procedures Performed on the Liulin Space Radiation Dosimeter; and Radiation Environment Monitoring for Astronauts.
Automated size-specific CT dose monitoring program: assessing variability in CT dose.
Christianson, Olav; Li, Xiang; Frush, Donald; Samei, Ehsan
2012-11-01
The potential health risks associated with low levels of ionizing radiation have created a movement in the radiology community to optimize computed tomography (CT) imaging protocols to use the lowest radiation dose possible without compromising the diagnostic usefulness of the images. Despite efforts to use appropriate and consistent radiation doses, studies suggest that a great deal of variability in radiation dose exists both within and between institutions for CT imaging. In this context, the authors have developed an automated size-specific radiation dose monitoring program for CT and used this program to assess variability in size-adjusted effective dose from CT imaging. The authors radiation dose monitoring program operates on an independent health insurance portability and accountability act compliant dosimetry server. Digital imaging and communication in medicine routing software is used to isolate dose report screen captures and scout images for all incoming CT studies. Effective dose conversion factors (k-factors) are determined based on the protocol and optical character recognition is used to extract the CT dose index and dose-length product. The patient's thickness is obtained by applying an adaptive thresholding algorithm to the scout images and is used to calculate the size-adjusted effective dose (ED(adj)). The radiation dose monitoring program was used to collect data on 6351 CT studies from three scanner models (GE Lightspeed Pro 16, GE Lightspeed VCT, and GE Definition CT750 HD) and two institutions over a one-month period and to analyze the variability in ED(adj) between scanner models and across institutions. No significant difference was found between computer measurements of patient thickness and observer measurements (p = 0.17), and the average difference between the two methods was less than 4%. Applying the size correction resulted in ED(adj) that differed by up to 44% from effective dose estimates that were not adjusted by patient size. Additionally, considerable differences were noted in ED(adj) distributions between scanners, with scanners employing iterative reconstruction exhibiting significantly lower ED(adj) (range: 9%-64%). Finally, a significant difference (up to 59%) in ED(adj) distributions was observed between institutions, indicating the potential for dose reduction. The authors developed a robust automated size-specific radiation dose monitoring program for CT. Using this program, significant differences in ED(adj) were observed between scanner models and across institutions. This new dose monitoring program offers a unique tool for improving quality assurance and standardization both within and across institutions.
Automated size-specific CT dose monitoring program: Assessing variability in CT dose
DOE Office of Scientific and Technical Information (OSTI.GOV)
Christianson, Olav; Li Xiang; Frush, Donald
2012-11-15
Purpose: The potential health risks associated with low levels of ionizing radiation have created a movement in the radiology community to optimize computed tomography (CT) imaging protocols to use the lowest radiation dose possible without compromising the diagnostic usefulness of the images. Despite efforts to use appropriate and consistent radiation doses, studies suggest that a great deal of variability in radiation dose exists both within and between institutions for CT imaging. In this context, the authors have developed an automated size-specific radiation dose monitoring program for CT and used this program to assess variability in size-adjusted effective dose from CTmore » imaging. Methods: The authors radiation dose monitoring program operates on an independent health insurance portability and accountability act compliant dosimetry server. Digital imaging and communication in medicine routing software is used to isolate dose report screen captures and scout images for all incoming CT studies. Effective dose conversion factors (k-factors) are determined based on the protocol and optical character recognition is used to extract the CT dose index and dose-length product. The patient's thickness is obtained by applying an adaptive thresholding algorithm to the scout images and is used to calculate the size-adjusted effective dose (ED{sub adj}). The radiation dose monitoring program was used to collect data on 6351 CT studies from three scanner models (GE Lightspeed Pro 16, GE Lightspeed VCT, and GE Definition CT750 HD) and two institutions over a one-month period and to analyze the variability in ED{sub adj} between scanner models and across institutions. Results: No significant difference was found between computer measurements of patient thickness and observer measurements (p= 0.17), and the average difference between the two methods was less than 4%. Applying the size correction resulted in ED{sub adj} that differed by up to 44% from effective dose estimates that were not adjusted by patient size. Additionally, considerable differences were noted in ED{sub adj} distributions between scanners, with scanners employing iterative reconstruction exhibiting significantly lower ED{sub adj} (range: 9%-64%). Finally, a significant difference (up to 59%) in ED{sub adj} distributions was observed between institutions, indicating the potential for dose reduction. Conclusions: The authors developed a robust automated size-specific radiation dose monitoring program for CT. Using this program, significant differences in ED{sub adj} were observed between scanner models and across institutions. This new dose monitoring program offers a unique tool for improving quality assurance and standardization both within and across institutions.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Park, J; Molecular Imaging Program at Stanford, Stanford, CA; Bio-X Program, Stanford, CA
2015-06-15
Purpose: To evaluate radiation responses of the medulloblastoma cell line Daoy in intensity-modulated radiation therapy (IMRT), quantitative variations to variable radiation dosimetic parameters were tracked by bioluminescent images (BLIs). Methods: The luciferase and green fluorescent protein positive Daoy cells were cultured on dishes. The medulloblastoma cells irradiated to different dose rate, interval of fractionated doses, field margin and misalignment, and dose uniformity in IMRT were monitored using bioluminescent images. The cultured cells were placed into a dedicated acrylic phantom to deliver intensity-modulated fluences and calculate accurate predicted dose distribution. The radiation with dose rate from 0.5 Gy/min to 15 Gy/minmore » was irradiated by adjusting monitor unit per minute and source-to-surface distances. The intervals of fractionated dose delivery were changed considering the repair time of double strand breaks (DSB) revealed by straining of gamma-H2AX.The effect of non-uniform doses on the cells were visualized by registering dose distributions and BLIs. The viability according to dosimetric parameters was correlated with bioluminescent intensities for cross-check of radiation responses. Results: The DSB and cell responses due to the first fractionated dose delivery significantly affected final tumor control rather than other parameters. The missing tumor volumes due to the smaller field margin than the tumor periphery or field misalignment caused relapse of cell responses on BLIs. The dose rate and gradient had effect on initial responses but could not bring out the distinguishable killing effect on cancer cells. Conclusion: Visualized and quantified bioluminescent images were useful to correlate the dose distributions with spatial radiation effects on cells. This would derive the effective combination of dose delivery parameters and fractionation. Radiation responses in particular IMRT configuration could be reflected to image based-dose re-optimization.« less
NASA Astrophysics Data System (ADS)
Faustov, A.; Gussarov, A.; Wuilpart, M.; Fotiadi, A. A.; Liokumovich, L. B.; Kotov, O. I.; Zolotovskiy, I. O.; Tomashuk, A. L.; Deschoutheete, T.; Mégret, P.
2012-04-01
On-line monitoring of environmental conditions in nuclear facilities is becoming a more and more important problem. Standard electronic sensors are not the ideal solution due to radiation sensitivity and difficulties in installation of multiple sensors. In contrast, radiation-hard optical fibres can sustain very high radiation doses and also naturally offer multi-point or distributed monitoring of external perturbations. Multiple local electro-mechanical sensors can be replaced by just one measuring fibre. At present, there are over four hundred operational nuclear power plants (NPPs) in the world 1. Operating experience has shown that ineffective control of the ageing degradation of major NPP components can threaten plant safety and also plant life. Among those elements, cables are vital components of I&C systems in NPPs. To ensure their safe operation and predict remaining life, environmental monitoring is necessary. In particular, temperature and radiation dose are considered to be the two most important parameters. The aim of this paper is to assess experimentally the feasibility of optical fibre temperature measurements in a low doserate radiation environment, using a commercially available reflectometer based on Rayleigh backscattering. Four different fibres were installed in the Sub-Pile Room of the BR2 Material testing nuclear reactor in Mol, Belgium. This place is man-accessible during the reactor shut-down, allowing easy fibre installation. When the reactor operates, the dose-rates in the room are in a range 0.005-5 Gy/h with temperatures of 40-60 °C, depending on the location. Such a surrounding is not much different to some "hot" environments in NPPs, where I&C cables are located.
Some computer graphical user interfaces in radiation therapy
Chow, James C L
2016-01-01
In this review, five graphical user interfaces (GUIs) used in radiation therapy practices and researches are introduced. They are: (1) the treatment time calculator, superficial X-ray treatment time calculator (SUPCALC) used in the superficial X-ray radiation therapy; (2) the monitor unit calculator, electron monitor unit calculator (EMUC) used in the electron radiation therapy; (3) the multileaf collimator machine file creator, sliding window intensity modulated radiotherapy (SWIMRT) used in generating fluence map for research and quality assurance in intensity modulated radiation therapy; (4) the treatment planning system, DOSCTP used in the calculation of 3D dose distribution using Monte Carlo simulation; and (5) the monitor unit calculator, photon beam monitor unit calculator (PMUC) used in photon beam radiation therapy. One common issue of these GUIs is that all user-friendly interfaces are linked to complex formulas and algorithms based on various theories, which do not have to be understood and noted by the user. In that case, user only needs to input the required information with help from graphical elements in order to produce desired results. SUPCALC is a superficial radiation treatment time calculator using the GUI technique to provide a convenient way for radiation therapist to calculate the treatment time, and keep a record for the skin cancer patient. EMUC is an electron monitor unit calculator for electron radiation therapy. Instead of doing hand calculation according to pre-determined dosimetric tables, clinical user needs only to input the required drawing of electron field in computer graphical file format, prescription dose, and beam parameters to EMUC to calculate the required monitor unit for the electron beam treatment. EMUC is based on a semi-experimental theory of sector-integration algorithm. SWIMRT is a multileaf collimator machine file creator to generate a fluence map produced by a medical linear accelerator. This machine file controls the multileaf collimator to deliver intensity modulated beams for a specific fluence map used in quality assurance or research. DOSCTP is a treatment planning system using the computed tomography images. Radiation beams (photon or electron) with different energies and field sizes produced by a linear accelerator can be placed in different positions to irradiate the tumour in the patient. DOSCTP is linked to a Monte Carlo simulation engine using the EGSnrc-based code, so that 3D dose distribution can be determined accurately for radiation therapy. Moreover, DOSCTP can be used for treatment planning of patient or small animal. PMUC is a GUI for calculation of the monitor unit based on the prescription dose of patient in photon beam radiation therapy. The calculation is based on dose corrections in changes of photon beam energy, treatment depth, field size, jaw position, beam axis, treatment distance and beam modifiers. All GUIs mentioned in this review were written either by the Microsoft Visual Basic.net or a MATLAB GUI development tool called GUIDE. In addition, all GUIs were verified and tested using measurements to ensure their accuracies were up to clinical acceptable levels for implementations. PMID:27027225
Parretta, Antonio; Privato, Carlo; Nenna, Giuseppe; Antonini, Andrea; Stefancich, Marco
2006-10-20
Methods for evaluating the light intensity distribution on receivers of concentrated solar radiation systems are described. They are based on the use of Lambertian diffusers in place of the illuminated receiver and on the acquisition of the scattered light, in reflection or transmission mode, by a CCD camera. The spatial distribution of intensity radiation is then numerically derived from the recorded images via a proprietary code. The details of the method are presented and a short survey of the main applications of the method in the photovoltaic and thermal solar energy conversion field is proposed. Methods for investigating the Lambertian character of commercial diffusers are also discussed.
1989-12-01
Report 2b Declassification Downgrading Schedule Approved for public release; distribution is unlimited. 4 Performing Organization Report Number(s) 5...Monitoring Organization Report Number(s) 6a Name of Performing Organization 6b Office Symbol 7a Name of Monitoring Organization Naval Postraduate School (if... Prodcution Ratio. DS vs. MIT........................ 29 Figure 15. Cerenkov Weights at Detector ........... I.................... 30 Figure 16. Ratio at
Ochi, Kotaro; Sasaki, Miyuki; Ishida, Mutsushi; Hamamoto, Shoichiro; Nishimura, Taku; Sanada, Yukihisa
2017-08-17
After the Fukushima Daiichi Nuclear Power Plant accident, the vertical distribution of radiocesium in soil has been investigated to better understand the behavior of radiocesium in the environment. The typical method used for measuring the vertical distribution of radiocesium is troublesome because it requires collection and measurement of the activity of soil samples. In this study, we established a method of estimating the vertical distribution of radiocesium by focusing on the characteristics of gamma-ray spectra obtained via aerial radiation monitoring using an unmanned helicopter. The estimates are based on actual measurement data collected at an extended farm. In this method, the change in the ratio of direct gamma rays to scattered gamma rays at various depths in the soil was utilized to quantify the vertical distribution of radiocesium. The results show a positive correlation between the abovementioned and the actual vertical distributions of radiocesium measured in the soil samples. A vertical distribution map was created on the basis of this ratio using a simple equation derived from the abovementioned correlation. This technique can provide a novel approach for effective selection of high-priority areas that require decontamination.
Ochi, Kotaro; Sasaki, Miyuki; Ishida, Mutsushi; Sanada, Yukihisa
2017-01-01
After the Fukushima Daiichi Nuclear Power Plant accident, the vertical distribution of radiocesium in soil has been investigated to better understand the behavior of radiocesium in the environment. The typical method used for measuring the vertical distribution of radiocesium is troublesome because it requires collection and measurement of the activity of soil samples. In this study, we established a method of estimating the vertical distribution of radiocesium by focusing on the characteristics of gamma-ray spectra obtained via aerial radiation monitoring using an unmanned helicopter. The estimates are based on actual measurement data collected at an extended farm. In this method, the change in the ratio of direct gamma rays to scattered gamma rays at various depths in the soil was utilized to quantify the vertical distribution of radiocesium. The results show a positive correlation between the abovementioned and the actual vertical distributions of radiocesium measured in the soil samples. A vertical distribution map was created on the basis of this ratio using a simple equation derived from the abovementioned correlation. This technique can provide a novel approach for effective selection of high-priority areas that require decontamination. PMID:28817098
Cournane, S; Sheehy, N; Cooke, J
2014-06-01
Benford's law is an empirical observation which predicts the expected frequency of digits in naturally occurring datasets spanning multiple orders of magnitude, with the law having been most successfully applied as an audit tool in accountancy. This study investigated the sensitivity of the technique in identifying system output changes using simulated changes in interventional radiology Dose-Area-Product (DAP) data, with any deviations from Benford's distribution identified using z-statistics. The radiation output for interventional radiology X-ray equipment is monitored annually during quality control testing; however, for a considerable portion of the year an increased output of the system, potentially caused by engineering adjustments or spontaneous system faults may go unnoticed, leading to a potential increase in the radiation dose to patients. In normal operation recorded examination radiation outputs vary over multiple orders of magnitude rendering the application of normal statistics ineffective for detecting systematic changes in the output. In this work, the annual DAP datasets complied with Benford's first order law for first, second and combinations of the first and second digits. Further, a continuous 'rolling' second order technique was devised for trending simulated changes over shorter timescales. This distribution analysis, the first employment of the method for radiation output trending, detected significant changes simulated on the original data, proving the technique useful in this case. The potential is demonstrated for implementation of this novel analysis for monitoring and identifying change in suitable datasets for the purpose of system process control. Copyright © 2013 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.
NASA Astrophysics Data System (ADS)
Gutschwager, Berndt; Hollandt, Jörg
2017-01-01
We present a novel method of nonuniformity correction (NUC) of infrared cameras and focal plane arrays (FPA) in a wide optical spectral range by reading radiance temperatures and by applying a radiation source with an unknown and spatially nonhomogeneous radiance temperature distribution. The benefit of this novel method is that it works with the display and the calculation of radiance temperatures, it can be applied to radiation sources of arbitrary spatial radiance temperature distribution, and it only requires sufficient temporal stability of this distribution during the measurement process. In contrast to this method, an initially presented method described the calculation of NUC correction with the reading of monitored radiance values. Both methods are based on the recording of several (at least three) images of a radiation source and a purposeful row- and line-shift of these sequent images in relation to the first primary image. The mathematical procedure is explained in detail. Its numerical verification with a source of a predefined nonhomogeneous radiance temperature distribution and a thermal imager of a predefined nonuniform FPA responsivity is presented.
New Organic Scintillators for Neutron Detection
2016-03-01
highly enriched uranium and weapons grade plutonium. Neutrons and gamma rays are two signatures of these materials. Gamma ray detection techniques are...New Organic Scintillators for Neutron Detection Distribution Statement A. Approved for public release; distribution is unlimited. March...Title: New Organic Scintillators for Neutron Detection I. Abstract In this project, Radiation Monitoring Devices (RMD) proposes to develop novel
Silva, T F; Bonini, A L; Lima, R R; Maidana, N L; Malafronte, A A; Pascholati, P R; Vanin, V R; Martins, M N
2012-09-01
Optical transition radiation (OTR) plays an important role in beam diagnostics for high energy particle accelerators. Its linear intensity with beam current is a great advantage as compared to fluorescent screens, which are subject to saturation. Moreover, the measurement of the angular distribution of the emitted radiation enables the determination of many beam parameters in a single observation point. However, few works deals with the application of OTR to monitor low energy beams. In this work we describe the design of an OTR based beam monitor used to measure the transverse beam charge distribution of the 1.9-MeV electron beam of the linac injector of the IFUSP microtron using a standard vision machine camera. The average beam current in pulsed operation mode is of the order of tens of nano-Amps. Low energy and low beam current make OTR observation difficult. To improve sensitivity, the beam incidence angle on the target was chosen to maximize the photon flux in the camera field-of-view. Measurements that assess OTR observation (linearity with beam current, polarization, and spectrum shape) are presented, as well as a typical 1.9-MeV electron beam charge distribution obtained from OTR. Some aspects of emittance measurement using this device are also discussed.
NASA Astrophysics Data System (ADS)
Bieber, J. W.; Clem, J.; Evenson, P.; Kuwabara, T.; Pyle, R.; Ruffolo, D.; Saiz, A.
2007-12-01
Neutron monitors are ground-based instruments that record the byproducts of collisions between cosmic rays and molecules in Earth's atmosphere. When linked together in real-time coordinated arrays, these instruments can make valuable contributions to the specification of major solar energetic particle events. Neutron monitors can provide the earliest alert of elevated radiation levels in Earth's atmosphere caused by the arrival of relativistic solar particles (Ground Level Enhancement or GLE). Early detection of GLE is of interest to the aviation industry because of the associated radiation hazard for pilots and air crews, especially for those flying polar routes. Network observations can also be used to map, in principle in real time, the distribution of radiation in Earth's atmosphere, taking into account the particle anisotropy which can be very large in early phases of the event. Observations from the large GLE of January 20, 2005 and December 13, 2006 will be used to illustrate these applications of neutron monitors. Supported by NSF grant ATM-0527878, the Thailand Research Fund, and the Mahidol University Postdoctoral Fellowship Program.
NASA Astrophysics Data System (ADS)
Caratelli, A.; Bonacini, S.; Kloukinas, K.; Marchioro, A.; Moreira, P.; De Oliveira, R.; Paillard, C.
2015-03-01
The future upgrades of the LHC experiments will increase the beam luminosity leading to a corresponding growth of the amounts of data to be treated by the data acquisition systems. To address these needs, the GBT (Giga-Bit Transceiver optical link [1,2]) architecture was developed to provide the simultaneous transfer of readout data, timing and trigger signals as well as slow control and monitoring data. The GBT-SCA ASIC, part of the GBT chip-set, has the purpose to distribute control and monitoring signals to the on-detector front-end electronics and perform monitoring operations of detector environmental parameters. In order to meet the requirements of different front-end ASICs used in the experiments, it provides various user-configurable interfaces capable to perform simultaneous operations. It is designed employing radiation tolerant design techniques to ensure robustness against SEUs and TID radiation effects and is implemented in a commercial 130 nm CMOS technology. This work presents the GBT-SCA architecture, the ASIC interfaces, the data transfer protocol, and its integration with the GBT optical link.
Electrical impedance tomography.
Costa, Eduardo L V; Lima, Raul Gonzalez; Amato, Marcelo B P
2009-02-01
Electrical impedance tomography (EIT) is a noninvasive, radiation-free monitoring tool that allows real-time imaging of ventilation. The purpose of this article is to discuss the fundamentals of EIT and to review the use of EIT in critical care patients. In addition to its established role in describing the distribution of alveolar ventilation, EIT has been shown to be a useful tool to detect lung collapse and monitor lung recruitment, both regionally and on a global basis. EIT has also been used to diagnose with high sensitivity incident pneumothoraces during mechanical ventilation. Additionally, with injection of hypertonic saline as a contrast agent, it is possible to estimate ventilation/perfusion distributions. EIT is cheap, noninvasive and allows continuous monitoring of ventilation. It is gaining acceptance as a valuable monitoring tool for the care of critical patients.
SRAG Measurements Performed During the Orion EFT-1 Mission
NASA Technical Reports Server (NTRS)
Gaza, Ramona
2015-01-01
The Exploration Flight Test 1 (EFT-1) was the first flight of the Orion Multi-Purpose Crew Vehicle (MPCV). The flight was launched on December 5, 2014, by a Delta IV Heavy rocket and lasted 4.5 hours. The EFT-1 trajectory involved one low altitude orbit and one high altitude orbit with an apogee of almost 6000 km. As a result of this particular flight profile, the Orion MPCV passed through intense regions of trapped protons and electron belts. In support of the radiation measurements aboard the EFT-1, the Space Radiation Analysis Group (SRAG) provided a Battery-operated Independent Radiation Detector (BIRD) based on Timepix radiation monitoring technology similar to that employed by the ISS Radiation Environmental Monitors (REM). In addition, SRAG provided a suite of optically and thermally stimulated luminescence detectors, with 2 Radiation Area Monitor (RAM) units collocated with the BIRD instrument for comparison purposes, and 6 RAM units distributed at different shielding configurations within the Orion MPCV. A summary of the EFT-1 Radiation Area Monitors (RAM) mission dose results obtained from measurements performed in the Space Radiation Dosimetry Laboratory at the NASA Johnson Space Center will be presented. Each RAM included LiF:Mg,Ti (TLD-100), (6)LiF:Mg,Ti (TLD-600), (7)LiF:Mg,Ti (TLD-700), Al2O3:C (Luxel trademark), and CaF2:Tm (TLD-300). The RAM mission dose values will be compared with the BIRD instrument total mission dose. In addition, a similar comparison will be shown for the ISS environment by comparing the ISS RAM data with data from the six Timepix-based REM units deployed on ISS as part of the NASA REM Technology Demonstration.
Assessment of medical occupational radiation doses in Costa Rica.
Mora, P; Acuña, M
2011-09-01
Participation of the University of Costa Rica (UCR) in activities in an IAEA Regional Project RLA/9/066 through training, equipment and expert missions, has enabled to setting up of a national personal monitoring laboratory. Since 2007, the UCR has been in charge of monitoring around 1800 medical radiation workers of the Social Security System. Individual external doses are measured with thermoluminescent dosemeter using a Harshaw 6600 Plus reader. The service has accreditation with ISO/IEC 17025:2005. Distribution of monitored medical personnel is as follows: 83 % in diagnostic radiology, 6 % in nuclear medicine and 6 % in radiotherapy. Preliminary values for the 75 percentile of annual H(p)(10) in mSv are: radiology 0.37; interventional radiology 0.41; radiotherapy 0.53 and nuclear medicine 1.55. The service provided by the UCR in a steady and reliable way can help to implement actions to limit the doses received by the medical workers and optimise their radiation protection programs.
Space Weather Nowcasting of Atmospheric Ionizing Radiation for Aviation Safety
NASA Technical Reports Server (NTRS)
Mertens, Christopher J.; Wilson, John W.; Blattnig, Steve R.; Solomon, Stan C.; Wiltberger, J.; Kunches, Joseph; Kress, Brian T.; Murray, John J.
2007-01-01
There is a growing concern for the health and safety of commercial aircrew and passengers due to their exposure to ionizing radiation with high linear energy transfer (LET), particularly at high latitudes. The International Commission of Radiobiological Protection (ICRP), the EPA, and the FAA consider the crews of commercial aircraft as radiation workers. During solar energetic particle (SEP) events, radiation exposure can exceed annual limits, and the number of serious health effects is expected to be quite high if precautions are not taken. There is a need for a capability to monitor the real-time, global background radiations levels, from galactic cosmic rays (GCR), at commercial airline altitudes and to provide analytical input for airline operations decisions for altering flight paths and altitudes for the mitigation and reduction of radiation exposure levels during a SEP event. The Nowcast of Atmospheric Ionizing Radiation for Aviation Safety (NAIRAS) model is new initiative to provide a global, real-time radiation dosimetry package for archiving and assessing the biologically harmful radiation exposure levels at commercial airline altitudes. The NAIRAS model brings to bear the best available suite of Sun-Earth observations and models for simulating the atmospheric ionizing radiation environment. Observations are utilized from ground (neutron monitors), from the atmosphere (the METO analysis), and from space (NASA/ACE and NOAA/GOES). Atmospheric observations provide the overhead shielding information and the ground- and space-based observations provide boundary conditions on the GCR and SEP energy flux distributions for transport and dosimetry simulations. Dose rates are calculated using the parametric AIR (Atmospheric Ionizing Radiation) model and the physics-based HZETRN (High Charge and Energy Transport) code. Empirical models of the near-Earth radiation environment (GCR/SEP energy flux distributions and geomagnetic cut-off rigidity) are benchmarked against the physics-based CMIT (Coupled Magnetosphere- Ionosphere-Thermosphere) and SEP-trajectory models.
Distributed FBG sensors apply in spacecraft health monitoring
NASA Astrophysics Data System (ADS)
Huang, Xiujun; Zhang, Cuicui; Shi, Dele; Shen, Jingshi
2017-10-01
At present, Spacecraft manufacturing face with high adventure for its complicate structure, serious space environment and not maintained on orbit. When something wrong with spacecraft, monitoring its health state, supply health data in real time would assure quickly locate error and save more time to rescue it. For FBG sensor can distributed test several parameters such as temperature, strain, vibration and easily construct net. At same time, it has more advantages such as ant-radiate, anti-jamming, rodent-resistant and with long lifetime, which more fit for applying in space. In this paper, a spacecraft health monitor system based on FBG sensors is present, Firstly, spacecraft health monitor system and its development are introduced. Then a four channels FBG demodulator is design. At last, Temperature and strain detecting experiment is done. The result shows that the demodulator fully satisfied the need of spacecraft health monitor system.
Interpretation of TEPC Measurements in Space Flights for Radiation Monitoring
NASA Technical Reports Server (NTRS)
Kim, Myung-Hee Y.; Nikjoo, Hooshang; Dicello, John F.; Pisacane, Vincent; Cucinotta, Francis A.
2007-01-01
For the proper interpretation of radiation data measured in space, the results of integrated radiation transport models were compared with the tissue equivalent proportional counter (TEPC) measurements. TEPC is a simple, time-dependent approach to radiation monitoring for astronauts on board the International Space Station. Another and a newer approach to microdosimetry is the use of silicon-on-insulator (SOI) technology launched on the MidSTAR-1 mission in low Earth orbit (LEO). In the radiation protection practice, the average quality factor of a radiation field is defined as a function of linear energy transfer (LET), Qave(LET). However, TEPC measures the average quality factor as a function of the lineal energy y, Qave(y), defined as the average energy deposition in a volume divided by the average chord length of the volume. The deviation of y from LET is caused by energy straggling, delta-ray escape or entry, and nuclear fragments produced in the detector volume. The response distribution functions of the wall-less and walled TEPCs were calculated from Monte-Carlo track simulations. Using an integrated space radiation model (which includes the transport codes HZETRN and BRYNTRN, and the quantum nuclear interaction model QMSFRG) and the resultant response distribution functions from Monte-Carlo track simulations, we compared model calculations with the walled-TEPC measurements from NASA missions in LEO and made predictions for the lunar and the Mars missions. Good agreement was found for Qave(y) between the model and measured spectra from past NASA missions. The Qave(y) values for the trapped or the solar protons ranged from 1.9-2.5. This over-estimates the Qave(LET) values which ranged from 1.4-1.6. Both quantities increase with shield thickness due to nuclear fragmentation. The Qave(LET) for the complete GCR spectra was found to be 3.5-4.5, while flight TEPCs measured 2.9-3.4 for Qave(y). The GCR values are decreasing with the shield thickness. Our analysis of the measurements of TEPCs can be used for a proper interpretation of observed data of monitoring the space radiation environment.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Fetterly, K; Schueler, B; Grams, M
Purpose: The purpose of this work was to characterize the spatial distribution of scatter radiation to the head and neck of a physician performing an x-ray interventional procedure and assess brain, eye lens, and carotid artery dose. Methods: Radiographic x-ray beams were tuned to match the peak energy (56 to 106 keV) and HVL (3.5 to 6.5 mm Al) of x-ray scatter originating from a patient during a fluoroscopic procedure. The radiographic beam was directed upon a Rando phantom from an inferior-left location to mimic a typical patient-operator geometric relationship. A lead-equivalent protective garment was secured to the phantom. Directmore » exposure Gafchromic film (XRQA2) was placed between the transverse plane layers of the head and neck region of the phantom and exposed with 4 scatter-equivalent radiographic beams. A 3×3 cm{sup 2} film placed at the left collar of the phantom was used to monitor incident dose in the position of a radiation monitoring badge. The films were converted to 2D dose distribution maps using FilmQA Pro software and an Epson 11000-XL scanner. The 2D dose distributions maps were normalized by the left collar dose and the percent of left collar dose (%LCD) was calculated for select tissues. Results: The dose maps had high dynamic range (10{sub 4}) and spatial detail. Considering all transverse planes and 4 scatter beam qualities, the median %LCD values were: whole brain 8.5%, left brain 13%, right brain 5.4%, left eye lens 67%, right eye lens 25%, left carotid artery 72%, and right carotid artery 28%. Conclusion: Scatter radiation dose to an operator can be simulated using a tuned radiographic beam and used to expose a phantom and Gafchromic film, thereby creating detailed 2D dose distribution maps. This work facilitates individualized estimation of dose to select head and neck tissues based on an operator’s radiation monitoring badge value.« less
Monitoring and Modeling Astronaut Occupational Radiation Exposures in Space: Recent Advances
NASA Technical Reports Server (NTRS)
Weyland, Mark; Golightly, Michael
1999-01-01
In 1982 astronauts were declared to be radiation workers by OSHA, and as such were subject to the rules and regulations applied to that group. NASA was already aware that space radiation was a hazard to crewmembers and had been studying and monitoring astronaut doses since 1962 at the Johnson Space Center. It was quickly realized NASA would not be able to accomplish all of its goals if the astronauts were subject to the ground based radiation worker limits, and thus received a waiver from OSHA to establish independent limits. As part of the stipulation attached to setting new limits, OSHA included a requirement to perform preflight dose projections for each crew and inform them of the associated risks. Additional requirements included measuring doses from various sources during the flight, making every effort to prevent a crewmember from exceeding the new limits, and keeping all exposures As Low As Reasonably Achievable (a.k.a. ALARA - a common health physics principle). The assembly of the International Space Station (ISS) and its initial manned operations will coincide with the 4-5 year period of high space weather activity at the next maximum in the solar cycle. For the first time in NASA's manned program, US astronauts will be in orbit continuously throughout a solar maximum period. During this period, crews are at risk of significantly increased radiation exposures due to solar particle events and trapped electron belt enhancements following geomagnetic storms. The problem of protecting crews is compounded by the difficulty of providing continuous real-time monitoring over a period of a decade in an era of tightly constrained budgets. In order to prepare for ISS radiological support needs, the NASA Space Radiation Analysis Group and the NOAA Space Environment Center have undertaken a multiyear effort to improve and automate ground-based space weather monitoring systems and real-time radiation analysis tools. These improvements include a coupled, automated space weather monitoring and alarm system--SPE exposure analysis system, an advanced space weather data distribution and display system, and a high-fidelity space weather simulation system. In addition, significant new real-time space weather data sets, which will enhance the forecasting and now-casting of near-Earth space environment conditions, are being made available through unique NASA-NOAA-USAF collaborations. These new data sets include coronal mass ejection monitoring by the Solar and Heliospheric Observatory (SOHO) and in-situ plasma and particle monitoring at the L1 libration point by the Solar Wind Monitor (SWIM) and Advanced Composition Explorer (ACE) spacecraft. Advanced real-time radiation monitoring data from charged particle telescopes and tissue equivalent proportional counters will also be available to assist crew and flight controllers in monitoring the external and intravehicular radiation environment.
NASA Technical Reports Server (NTRS)
Frederickson, A. R.; Mullen, E. G.; Brautigam, D. H.; Kerns, K. J.
1992-01-01
The Internal Discharge Monitor (IDM) was designed to observe electrical pulses from common electrical insulators in space service. The sixteen insulator samples included twelve planar printed circuit boards and four cables. The samples were fully enclosed, mutually isolated, and space radiation penetrated 0.02 cm of aluminum before striking the samples. Pulsing began on the seventh orbit, the maximum pulse rate occurred on the seventeenth orbit when 13 pulses occurred, and the pulses slowly diminished to about one per 3 orbits six months later. After 8 months, the radiation belts abruptly increased and the pulse rates attained a new high. These pulse rates were in agreement with laboratory experience on shorter time scales. Several of the samples never pulsed. If the pulses were not confined within IDM, the physical processes could spread to become a full spacecraft anomaly. The IDM results indicate the rate at which small insulator pulses occur. Small pulses are the seeds of larger satellite electrical anomalies. The pulse rates are compared with space radiation intensities, L shell location, and spectral distributions from the radiation spectrometers on the Combined Release and Radiation Effects Satellite.
NASA Technical Reports Server (NTRS)
Fymat, A. L.
1976-01-01
The paper studies the inversion of the radiative transfer equation describing the interaction of electromagnetic radiation with atmospheric aerosols. The interaction can be considered as the propagation in the aerosol medium of two light beams: the direct beam in the line-of-sight attenuated by absorption and scattering, and the diffuse beam arising from scattering into the viewing direction, which propagates more or less in random fashion. The latter beam has single scattering and multiple scattering contributions. In the former case and for single scattering, the problem is reducible to first-kind Fredholm equations, while for multiple scattering it is necessary to invert partial integrodifferential equations. A nonlinear minimization search method, applicable to the solution of both types of problems has been developed, and is applied here to the problem of monitoring aerosol pollution, namely the complex refractive index and size distribution of aerosol particles.
Experimental study on infrared radiation temperature field of concrete under uniaxial compression
NASA Astrophysics Data System (ADS)
Lou, Quan; He, Xueqiu
2018-05-01
Infrared thermography, as a nondestructive, non-contact and real-time monitoring method, has great significance in assessing the stability of concrete structure and monitoring its failure. It is necessary to conduct in depth study on the mechanism and application of infrared radiation (IR) of concrete failure under loading. In this paper, the concrete specimens with size of 100 × 100 × 100 mm were adopted to carry out the uniaxial compressions for the IR tests. The distribution of IR temperatures (IRTs), surface topography of IRT field and the reconstructed IR images were studied. The results show that the IRT distribution follows the Gaussian distribution, and the R2 of Gaussian fitting changes along with the loading time. The abnormities of R2 and AE counts display the opposite variation trends. The surface topography of IRT field is similar to the hyperbolic paraboloid, which is related to the stress distribution in the sample. The R2 of hyperbolic paraboloid fitting presents an upward trend prior to the fracture which enables to change the IRT field significantly. This R2 has a sharp drop in response to this large destruction. The normalization images of IRT field, including the row and column normalization images, were proposed as auxiliary means to analyze the IRT field. The row and column normalization images respectively show the transverse and longitudinal distribution of the IRT field, and they have clear responses to the destruction occurring on the sample surface. In this paper, the new methods and quantitative index were proposed for the analysis of IRT field, which have some theoretical and instructive significance for the analysis of the characteristics of IRT field, as well as the monitoring of instability and failure for concrete structure.
Delepine-Lesoille, Sylvie; Girard, Sylvain; Landolt, Marcel; Bertrand, Johan; Planes, Isabelle; Boukenter, Aziz; Marin, Emmanuel; Humbert, Georges; Leparmentier, Stéphanie; Auguste, Jean-Louis; Ouerdane, Youcef
2017-06-13
This paper presents the state of the art distributed sensing systems, based on optical fibres, developed and qualified for the French Cigéo project, the underground repository for high level and intermediate level long-lived radioactive wastes. Four main parameters, namely strain, temperature, radiation and hydrogen concentration are currently investigated by optical fibre sensors, as well as the tolerances of selected technologies to the unique constraints of the Cigéo's severe environment. Using fluorine-doped silica optical fibre surrounded by a carbon layer and polyimide coating, it is possible to exploit its Raman, Brillouin and Rayleigh scattering signatures to achieve the distributed sensing of the temperature and the strain inside the repository cells of radioactive wastes. Regarding the dose measurement, promising solutions are proposed based on Radiation Induced Attenuation (RIA) responses of sensitive fibres such as the P-doped ones. While for hydrogen measurements, the potential of specialty optical fibres with Pd particles embedded in their silica matrix is currently studied for this gas monitoring through its impact on the fibre Brillouin signature evolution.
Delepine-Lesoille, Sylvie; Girard, Sylvain; Landolt, Marcel; Bertrand, Johan; Planes, Isabelle; Boukenter, Aziz; Marin, Emmanuel; Humbert, Georges; Leparmentier, Stéphanie; Auguste, Jean-Louis; Ouerdane, Youcef
2017-01-01
This paper presents the state of the art distributed sensing systems, based on optical fibres, developed and qualified for the French Cigéo project, the underground repository for high level and intermediate level long-lived radioactive wastes. Four main parameters, namely strain, temperature, radiation and hydrogen concentration are currently investigated by optical fibre sensors, as well as the tolerances of selected technologies to the unique constraints of the Cigéo’s severe environment. Using fluorine-doped silica optical fibre surrounded by a carbon layer and polyimide coating, it is possible to exploit its Raman, Brillouin and Rayleigh scattering signatures to achieve the distributed sensing of the temperature and the strain inside the repository cells of radioactive wastes. Regarding the dose measurement, promising solutions are proposed based on Radiation Induced Attenuation (RIA) responses of sensitive fibres such as the P-doped ones. While for hydrogen measurements, the potential of specialty optical fibres with Pd particles embedded in their silica matrix is currently studied for this gas monitoring through its impact on the fibre Brillouin signature evolution. PMID:28608831
NASA Astrophysics Data System (ADS)
Shenfeld, Ofer; Belotserkovsky, Edward; Goldwasser, Benad; Zur, Albert; Katzir, Abraham
1993-02-01
The heating of tissue by microwave radiation has attained a place of importance in various medical fields, such as the treatment of malignancies, urinary retention, and hypothermia. Accurate temperature measurements in these treated tissues is important for treatment planning and for the control of the heating process. It is also important to be able to measure spacial temperature distribution in the tissues because they are heated in a nonuniform way by the microwave radiation. Conventional temperature sensors used today are inaccurate in the presence of microwave radiation and require contact with the heated tissue. Fiber optic radiometry makes it possible to measure temperatures accurately in the presence of microwave radiation and does not require contact with the tissue. Accurate temperature measurements of tissues heated by microwave was obtained using a silver halide optic radiometer, enabling control of the heating process in other regions of the tissue samples. Temperature mappings of the heated tissues were performed and the nonuniform temperature distributions in these tissues was demonstrated.
NASA Astrophysics Data System (ADS)
Sun, Hui; Li, Xin; Hu, Mingyong
2017-08-01
The unique spatial distribution of corneal elasticity is shown by the nonhomogeneous structure of the cornea. It is critical to understanding how biomechanics control corneal stability and refraction and one way to do this job is non-invasive measurement of this distribution. Femtosecond laser pulses have the ability to induce optical breakdown and produced cavitation in the anterior and posterior cornea. A confocal ultrasonic transducer applied 6.5 ms acoustic radiation forcechirp bursts to the bubble at 1.5 MHz while monitoring bubble position using pulse-echoes at 20 MHz. The laser induced breakdown spectroscopy (LIBS) were measured in the anterior and posterior cornea with the plasmas that induced by the same femtosecond laser to see whether the laser induced plasmas signals will show relationship to Young's modulus.
Measurement of LET distribution and dose equivalent on board the space shuttle STS-65
NASA Technical Reports Server (NTRS)
Hayashi, T.; Doke, T.; Kikuchi, J.; Takeuchi, R.; Hasebe, N.; Ogura, K.; Nagaoka, S.; Kato, M.; Badhwar, G. D.
1996-01-01
Space radiation dosimetry measurements have been made on board the Space Shuttle STS-65 in the Second International Microgravity Laboratory (IML-2). In these measurements, three kinds of detectors were used; one is a newly developed active detector telescope called "Real-time Radiation Monitoring Device (RRMD)" utilizing silicon semi-conductor detectors and others are conventional detectors of thermoluminescence dosimeters (TLDs) and CR-39 plastic track detectors. Using the RRMD detector, the first attempt of real-time monitoring of space radiation has been achieved successfully for a continuous period of 251.3 h, giving the temporal variations of LET distribution, particle count rates, and rates of absorbed dose and dose equivalent. The RRMD results indicate that a clear enhancement of the number of trapped particles is seen at the South Atlantic Anomaly (SAA) without clear enhancement of dose equivalent, while some daily periodic enhancements of dose equivalent due to high LET particles are seen at the lower geomagnetic cutoff regions for galactic cosmic ray particles (GCRs). Therefore, the main contribution to dose equivalent is seen to be due to GCRs in this low altitude mission (300 km). Also, the dose equivalent rates obtained by TLDs and CR-39 ranged from 146.9 to 165.2 microSv/day and the average quality factors from 1.45 to 1.57 depending on the locations and directions of detectors inside the Space-lab at this highly protected orbit for space radiation with a small inclination (28.5 degrees) and a low altitude (300 km). The LET distributions obtained by two different detectors, RRMD and CR-39, are in good agreement in the region of 15-200 keV/mm and difference of these distributions in the regions of LET < 15 keV/mm and LET > 200 keV/mm can be explained by considering characteristics of CR-39 etched track formation especially for the low LET tracks.
Measurement of LET distribution and dose equivalent on board the space shuttle STS-65.
Hayashi, T; Doke, T; Kikuchi, J; Takeuchi, R; Hasebe, N; Ogura, K; Nagaoka, S; Kato, M; Badhwar, G D
1996-11-01
Space radiation dosimetry measurements have been made on board the Space Shuttle STS-65 in the Second International Microgravity Laboratory (IML-2). In these measurements, three kinds of detectors were used; one is a newly developed active detector telescope called "Real-time Radiation Monitoring Device (RRMD)" utilizing silicon semi-conductor detectors and others are conventional detectors of thermoluminescence dosimeters (TLDs) and CR-39 plastic track detectors. Using the RRMD detector, the first attempt of real-time monitoring of space radiation has been achieved successfully for a continuous period of 251.3 h, giving the temporal variations of LET distribution, particle count rates, and rates of absorbed dose and dose equivalent. The RRMD results indicate that a clear enhancement of the number of trapped particles is seen at the South Atlantic Anomaly (SAA) without clear enhancement of dose equivalent, while some daily periodic enhancements of dose equivalent due to high LET particles are seen at the lower geomagnetic cutoff regions for galactic cosmic ray particles (GCRs). Therefore, the main contribution to dose equivalent is seen to be due to GCRs in this low altitude mission (300 km). Also, the dose equivalent rates obtained by TLDs and CR-39 ranged from 146.9 to 165.2 microSv/day and the average quality factors from 1.45 to 1.57 depending on the locations and directions of detectors inside the Space-lab at this highly protected orbit for space radiation with a small inclination (28.5 degrees) and a low altitude (300 km). The LET distributions obtained by two different detectors, RRMD and CR-39, are in good agreement in the region of 15-200 keV/mm and difference of these distributions in the regions of LET < 15 keV/mm and LET > 200 keV/mm can be explained by considering characteristics of CR-39 etched track formation especially for the low LET tracks.
Infrared fiber optic temperature monitoring of biological tissues heated in a microwave oven
NASA Astrophysics Data System (ADS)
Belotserkovsky, Edward; Ashkenasy, Y.; Shenfeld, Ofer; Drizlikh, S.; Zur, Albert; Katzir, Abraham
1993-05-01
The heating of tissue by microwave radiation has attained a place of importance in various medical fields such as the treatment of malignancies, urinary retention and hypothermia. Accurate temperature measurements in these treated tissues is important for treatment planning and for the control of the heating process. It is also important to be able to measure spacial temperature distribution in the tissues because they are heated in a non uniform way by the microwave radiation. Fiber optic radiometry makes possible accurate temperature measurement in the presence of microwave radiation and does not require contact with the tissue. Using a IR silver halide fiber optic radiometric temperature sensor we obtained accurate temperature measurements of tissues heated by microwave, enabling us to control the heating process in all regions of the tissue. We also performed temperature mapping of the heated tissues and demonstrated the non-uniform temperature distributions in them.
NASA Technical Reports Server (NTRS)
Deepak, A.; Becher, J.
1979-01-01
Advanced remote sensing techniques and inversion methods for the measurement of characteristics of aerosol and gaseous species in the atmosphere were investigated. Of particular interest were the physical and chemical properties of aerosols, such as their size distribution, number concentration, and complex refractive index, and the vertical distribution of these properties on a local as well as global scale. Remote sensing techniques for monitoring of tropospheric aerosols were developed as well as satellite monitoring of upper tropospheric and stratospheric aerosols. Computer programs were developed for solving multiple scattering and radiative transfer problems, as well as inversion/retrieval problems. A necessary aspect of these efforts was to develop models of aerosol properties.
Hughes, Kevin A
2003-08-01
Factors affecting fecal microorganism survival and distribution in the Antarctic marine environment include solar radiation, water salinity, temperature, sea ice conditions, and fecal input by humans and local wildlife populations. This study assessed the influence of these factors on the distribution of presumptive fecal coliforms around Rothera Point, Adelaide Island, Antarctic Peninsula during the austral summer and winter of February 1999 to September 1999. Each factor had a different degree of influence depending on the time of year. In summer (February), although the station population was high, presumptive fecal coliform concentrations were low, probably due to the biologically damaging effects of solar radiation. However, summer algal blooms reduced penetration of solar radiation into the water column. By early winter (April), fecal coliform concentrations were high, due to increased fecal input by migrant wildlife, while solar radiation doses were low. By late winter (September), fecal coliform concentrations were high near the station sewage outfall, as sea ice formation limited solar radiation penetration into the sea and prevented wind-driven water circulation near the outfall. During this study, environmental factors masked the effect of station population numbers on sewage plume size. If sewage production increases throughout the Antarctic, environmental factors may become less significant and effective sewage waste management will become increasingly important. These findings highlight the need for year-round monitoring of fecal coliform distribution in Antarctic waters near research stations to produce realistic evaluations of sewage pollution persistence and dispersal.
Sanada, Yukihisa; Orita, Tadashi; Torii, Tatsuo
2016-12-01
Aerial radiological survey using an unmanned aerial vehicle (UAV) was applied to measurement surface contamination around the Fukushima Daiichi nuclear power station (FDNPS). An unmanned helicopter monitoring system (UHMS) was developed to survey the environmental effect of radioactive cesium scattered as a result of the FDNPS accident. The UHMS was used to monitor the area surrounding the FDNPS six times from 2012 to 2015. Quantitative changes in the radioactivity distribution trend were revealed from the results of these monitoring runs. With this information, we found that the actual reduction of dose rate was faster than the one calculated with radiocesium physical half-life. It is indicated that the attenuation effect of radiation by radiocesium penetration in soil is dominant as for reason of reduction of dose rate. Copyright © 2016 Elsevier Ltd. All rights reserved.
UV and IR laser radiation's interaction with metal film and teflon surfaces
NASA Astrophysics Data System (ADS)
Fedenev, A. V.; Alekseev, S. B.; Goncharenko, I. M.; Koval', N. N.; Lipatov, E. I.; Orlovskii, V. M.; Shulepov, M. A.; Tarasenko, V. F.
2003-04-01
The interaction of Xe ([lambda] [similar] 1.73 [mu]m) and XeCl (0.308 [mu]m) laser radiation with surfaces of metal and TiN-ceramic coatings on glass and steel substrates has been studied. Correlation between parameters of surface erosion versus laser-specific energy was investigated. Monitoring of laser-induced erosion on smooth polished surfaces was performed using optical microscopy. The correlation has been revealed between characteristic zones of thin coatings damaged by irradiation and energy distribution over the laser beam cross section allowing evaluation of defects and adhesion of coatings. The interaction of pulsed periodical CO2 ([lambda] [similar] 10.6 [mu]m), and Xe ([lambda] [similar] 1.73 [mu]m) laser radiation with surfaces of teflon (polytetrafluoroethylene—PTFE) has been studied. Monitoring of erosion track on surfaces was performed through optical microscopy. It has been shown that at pulsed periodical CO2-radiation interaction with teflon the sputtering of polymer with formation of submicron-size particles occurs. Dependencies of particle sizes, form, and sputtering velocity on laser pulse duration and target temperature have been obtained.
NASA Astrophysics Data System (ADS)
Cherviakov, M.
2015-12-01
One of the foremost challenges to monitoring the climate system is the ability to make a precise measurement of Earth's radiation budget components from space. Thereupon a new "Meteor-M" satellite program has been started in Russia. The first satellite of new generation "Meteor-M" № 1 was put into orbit in September, 2009 and second satellite "Meteor-M" № 2 - in July, 2014. Some measurements results obtained by the nadir looking medium field of view radiometers IKOR-M which was installed on "Meteor-M" satellites are presented. These equipments were created in Saratov State University under the direction of Yu. A. Sklyarov for monitoring of outgoing shortwave radiation (OSR), albedo and absorbed solar radiation (ASR) at TOA. The basic products of data processing are given in the form of global maps of distribution OSR, albedo and ASR. Such maps were made for each month during observation period. Fig. 1 presents the map of global distribution of monthly averaged values of albedo in April, 2014. Two series of measurements from two different IKOR-M are available. The first radiometer had worked from October, 2009 to August, 2014 and second - from August, 2014 to the present. Therefore, there is a period when both radiometers work at the same time. TOA fluxes deduced from the "Meteor-M" № 1 measurements in August, 2014 show very good agreement with the fluxes determined from "Meteor-M" № 2. The seasonal and interannual variations of OSR, albedo and ASR were discussed. The variations between SW radiation budget components seem to be within observational uncertainty and natural variability governed by cloudiness, water vapor and aerosol variations. It was assessed spatial and temporal variations of albedo and ASR over different regions. Latitudinal distributions of albedo and ASR were estimated in more detail. Meridional cross sections over oceans and land were used separately for this estimation. It was shown that the albedo and ASR data received from the radiometer IKOR-M can be used to detect El-Nino in the Pacific Ocean and monitoring of the East Asian Summer Monsoon. Other details of received data will are presented. The work was carried out under financial support of the Ministry of education and science of the Russian Federation within the framework of the base part (project code 2179).
1985-04-01
S 3. Open and examine the ureters, bladder, and urethra. Inspect all mucosal and serosal surfaces . 4. Observe male accessory sex organs; note size...release; distribution is 2b. OECLASSIFICATIONIOWNGRADING SCHEDULE unlimited. 4. PERFORMING ORGANIZATION REPORT NUMSER( S ) 5. MONITORING ORGANIZATION REPORT...NUMBER( S ) SR 28 USAFSAM-TR-85- 11 ~ b. OFFICE SYMBOL 7a. NAME OF MONITORING ORGANIZATION I (If ppliable) Dept. of Rehabilitation Med. USAF School of
Long Term Monitoring of Atmospheric Composition at NOAA - Driving Science with 60 Year-old Records
NASA Astrophysics Data System (ADS)
Butler, J. H.
2017-12-01
NOAA's Global Monitoring Division and its precursor organizations have provided some of the longest real-time records of the trends and distributions of climatically relevant substances in the atmosphere, some going back for 60 years (http://www.esrl.noaa.gov/gmd). The focus of these measurements has been on obtaining reliable records of global trends and distributions of these substances, but the experimental design and use of measurements have advanced over time with evolving scientific questions. Today, and into this century, scientific questions continue to progress and the observing systems that address them will need to progress accordingly. Long-term, ground based observing systems in NOAA's Global Monitoring Division focus largely on three sets of questions, two of which align with WCRP grand challenges. These are Carbon Cycle System Feedbacks, Trends in Surface Radiation and Cloud Distributions, and Recovery of Stratospheric Ozone. The data collected and analyzed help us understand radiative forcing, climate sensitivity, air quality, climate modification, renewable energy options, and arctic processes, and they are useful for verifying model output and satellite retrievals. Regional information will become increasingly important for mitigating and adapting to climate change, and this information must be accurate, precise, and without bias. NOAA, with its long-standing networks and its role in providing calibrations for partnering organizations, is well positioned to provide the linkages necessary to assure that regional measurements are comparable. This presentation will identify major, climate-relevant findings that have come from NOAA's networks in the past and will address the long-term monitoring needs to support decision-making over coming decades as society begins to seriously address climate change.
Temperature grid sensor for the measurement of spatial temperature distributions at object surfaces.
Schäfer, Thomas; Schubert, Markus; Hampel, Uwe
2013-01-25
This paper presents results of the development and application of a new temperature grid sensor based on the wire-mesh sensor principle. The grid sensor consists of a matrix of 256 Pt1000 platinum chip resistors and an associated electronics that measures the grid resistances with a multiplexing scheme at high speed. The individual sensor elements can be spatially distributed on an object surface and measure transient temperature distributions in real time. The advantage compared with other temperature field measurement approaches such as infrared cameras is that the object under investigation can be thermally insulated and the radiation properties of the surface do not affect the measurement accuracy. The sensor principle is therefore suited for various industrial monitoring applications. Its applicability for surface temperature monitoring has been demonstrated through heating and mixing experiments in a vessel.
Comparisons of Radiative Flux Distributions from Satellite Observations and Global Models
NASA Astrophysics Data System (ADS)
Raschke, Ehrhard; Kinne, Stefan; Wild, Martin; Stackhouse, Paul; Rossow, Bill
2014-05-01
Radiative flux distributions at the top of the atmosphere (TOA) and at the surface are compared between typical data from satellite observations and from global modeling. Averages of CERES, ISCCP and SRB data-products (for the same 4-year period) represent satellite observations. Central values of IPCC-4AR output (over a 12-year period) represent global modeling. At TOA, differences are dominated by differences for cloud-effects, which are extracted from the differences between all-sky and clear-sky radiative flux products. As satellite data are considered as TOA reference, these differences document the poor representation of clouds in global modeling, especially for low altitude clouds over oceans. At the surface the differences, caused by the different cloud treatment are overlaid by a general offset. Satellite products suggest a ca 15Wm-2 stronger surface net-imbalance (and with it stronger precipitation). Since surface products of satellite and modeling are based on simulations and many assumptions, this difference has remained an open issue. BSRN surface monitoring is too short and too sparsely distributed for clear answers to provide a reliable basis for validation.
Bristow, Bonnie; Aldehaim, Mohammed; Bonin, Katija; Lam, Candice Chee Ka; Wan, Stephanie J; Cao, Xingshan; Szumacher, Ewa
2017-06-02
The American Society for Radiation Oncology (ASTRO) and American Urological Association (AUA) developed post-prostatectomy radiotherapy (RT) guidelines to aid patient counseling on adjuvant (ART) and salvage radiotherapy (SRT). Our study compared how aware and compliant Canadian radiation oncologists and urologists are to these guidelines. Our online survey was distributed through the Canadian Association of Radiation Oncology (CARO) and Canadian Urology Association (CUA) to radiation oncologists and urologists that treat prostate cancer. We used Wilcoxon rank-sum test and Chi-square test to compare radiation oncologists and urologists. P values for significant findings are reported. A total of 128 participants responded the survey, 52 radiation oncologists, and 76 urologists. The majority (82%) of radiation oncologists had read these guidelines, compared to only 49% of urologists (p < 0.001). Radiation oncologists were more likely to recommend ART >50% for adverse pathological findings post-radical prostatectomy compared to urologists (76 vs. 51%, p = 0.011). Urologists were more likely to monitor their patient's PSA level post-prostatectomy compared to radiation oncologists (93 vs. 77%, p = 0.016). Post-thematic analysis of open-ended questions revealed that urologists rarely refer patients to radiation oncologists for ART, with radiation oncologists confirming that they rarely receive referrals. This study demonstrates the low compliance to ASTRO/AUA guidelines. While radiation oncologists were more aware and compliant to guidelines, urologists were significantly more likely to monitor their patient's PSA. This study highlighted the need for better communication between urologists and radiation oncologists, especially in referrals for ART, to facilitate treatment delivery that is concordant with ASTRO/AUA guidelines.
Okeyode, I C; Rabiu, J A; Alatise, O O; Makinde, V; Akinboro, F G; Al-Azmi, D; Mustapha, A O
2017-04-01
A radiation monitoring system comprising a Geiger-Muller counter connected to a smart phone via Bluetooth was used for a dose rate survey in some parts of south-western Nigeria. The smart phone has the Geographical Positioning System, which provides the navigation information and saves it along with the dose rate data. A large number of data points was obtained that shows the dose rate distribution within the region. The results show that the ambient dose rates in the region range from 60 to 520 nSv -1 and showed a bias that is attributable to the influence of geology on the ambient radiation dose in the region. The geology influence was demonstrated by superimposing the dose rate plot and the geological map of the area. The potential applications of the device in determining baseline information and in area monitoring, e.g. for lost or abandoned sources, radioactive materials stockpiles, etc., were discussed in the article, particularly against the background of Nigeria's plan to develop its nuclear power program. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
Sanada, Yukihisa; Torii, Tatsuo
2015-01-01
The Great East Japan Earthquake on March 11, 2011 generated a series of large tsunami that seriously damaged the Fukushima Dai-ichi Nuclear Power Plant (FDNPP), which resulted in the release of radioactive materials into the environment. To provide further details regarding the distribution of air dose rate and the distribution of radioactive cesium ((134)Cs and (137)Cs) deposition on the ground within a radius of approximately 5 km from the nuclear power plant, we carried out measurements using an unmanned helicopter equipped with a radiation detection system. The distribution of the air dose rate at a height of 1 m above the ground and the radioactive cesium deposition on the ground was calculated. Accordingly, the footprint of radioactive plumes that extended from the FDNPP was illustrated. Copyright © 2014 Elsevier Ltd. All rights reserved.
Challenges for Early Responders to a Nuclear / Radiological Terrorism Incident
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wells, M.A.; Stearns, L.J.; Davie, A.D.
2007-07-01
Even in the best of circumstances, most municipalities would face severe challenges in providing effective incident response to a large scale radiation release caused by nuclear terrorism or accident. Compounding obvious complexities, the effectiveness of first and early responders to a radiological emergency may also be hampered by an insufficient distribution of radiation detection and monitoring equipment, local policies concerning triage and field decontamination of critical victims, malfunctioning communications, inadequate inter-agency agility, and the psychological 'fear' impact on early responders. This paper examines several issues impeding the early response to nuclear terrorism incidents with specific consideration given to the on-goingmore » and forward-thinking preparedness efforts currently being developed in the Sacramento, California region. Specific recommendations are provided addressing hot zone protocols, radiation detection and monitoring equipment, hasty patient packaging techniques, vertically and horizontally integrated pre-event training, mitigating psychological fear, and protocols for the effective 'hand-off' from first responders to subsequent early response-recovery teams. (authors)« less
Organic Scintillation Detectors for Spectroscopic Radiation Portal Monitors
NASA Astrophysics Data System (ADS)
Paff, Marc Gerrit
Thousands of radiation portal monitors have been deployed worldwide to detect and deter the smuggling of nuclear and radiological materials that could be used in nefarious acts. Radiation portal monitors are often installed at bottlenecks where large amounts of people or goods must traverse. Examples of use include scanning cargo containers at shipping ports, vehicles at border crossings, and people at high profile functions and events. Traditional radiation portal monitors contain separate detectors for passively measuring neutron and gamma ray count rates. 3He tubes embedded in polyethylene and slabs of plastic scintillators are the most common detector materials used in radiation portal monitors. The radiation portal monitor alarm mechanism relies on measuring radiation count rates above user defined alarm thresholds. These alarm thresholds are set above natural background count rates. Minimizing false alarms caused by natural background and maximizing sensitivity to weakly emitting threat sources must be balanced when setting these alarm thresholds. Current radiation portal monitor designs suffer from frequent nuisance radiation alarms. These radiation nuisance alarms are most frequently caused by shipments of large quantities of naturally occurring radioactive material containing cargo, like kitty litter, as well as by humans who have recently undergone a nuclear medicine procedure, particularly 99mTc treatments. Current radiation portal monitors typically lack spectroscopic capabilities, so nuisance alarms must be screened out in time-intensive secondary inspections with handheld radiation detectors. Radiation portal monitors using organic liquid scintillation detectors were designed, built, and tested. A number of algorithms were developed to perform on-the-fly radionuclide identification of single and combination radiation sources moving past the portal monitor at speeds up to 2.2 m/s. The portal monitor designs were tested extensively with a variety of shielded and unshielded radiation sources, including special nuclear material, at the European Commission Joint Research Centre in Ispra, Italy. Common medical isotopes were measured at the C.S. Mott Children's Hospital and added to the radionuclide identification algorithms.
Design and qualification of the SEU/TD Radiation Monitor chip
NASA Technical Reports Server (NTRS)
Buehler, Martin G.; Blaes, Brent R.; Soli, George A.; Zamani, Nasser; Hicks, Kenneth A.
1992-01-01
This report describes the design, fabrication, and testing of the Single-Event Upset/Total Dose (SEU/TD) Radiation Monitor chip. The Radiation Monitor is scheduled to fly on the Mid-Course Space Experiment Satellite (MSX). The Radiation Monitor chip consists of a custom-designed 4-bit SRAM for heavy ion detection and three MOSFET's for monitoring total dose. In addition the Radiation Monitor chip was tested along with three diagnostic chips: the processor monitor and the reliability and fault chips. These chips revealed the quality of the CMOS fabrication process. The SEU/TD Radiation Monitor chip had an initial functional yield of 94.6 percent. Forty-three (43) SEU SRAM's and 14 Total Dose MOSFET's passed the hermeticity and final electrical tests and were delivered to LL.
Looking skyward to study ecosystem carbon dynamics
Dye, Dennis G.
2012-01-01
Between May and October 2011 the U.S. Geological Survey (USGS), in cooperation with the U.S. Department of Energy's Atmospheric Radiation Measurement (ARM) program, conducted a field campaign at the ARM Southern Great Plains site in north central Oklahoma to evaluate a new instrument for quantitative image-based monitoring of sky conditions and solar radiation. The High Dynamic Range All-Sky Imaging System (HDR-ASIS) was developed by USGS to support studies of cloud- and aerosol-induced variability in the geometric properties of solar radiation (the sky radiance distribution) and its effects on photosynthesis and uptake of carbon dioxide (CO2) by terrestrial ecosystems. Under a clean, cloudless atmosphere when the Sun is above the horizon, most of the solar radiation reaching an area of the Earth's surface is concentrated in a beam coming directly from the Sun; a relatively small proportion arrives as diffuse radiation from the rest of the sky. Clouds and atmospheric aerosols cause increased scattering of the beam radiation, which increases the proportion of diffuse radiation at the surface.
NASA Astrophysics Data System (ADS)
Ormachea, O.; Abrahamse, A.; Tolavi, N.; Romero, F.; Urquidi, O.; Pearce, J. M.; Andrews, R.
2013-11-01
We report on the design and installation of a spectrometer system for monitoring solar radiation in Cochabamba, Bolivia. Both the light intensity and the spectral distribution affect the power produced by a photovoltaic device. Local variations in the solar spectrum (especially compared to the AM1.5 standard) may have important implications for device optimization and energy yield estimation. The spectrometer system, based on an Ocean Optics USB4000 (300-900nm) spectrometer, was designed to increase functionality. Typically systems only record the global horizontal radiation. Our system moves a fiber-optic cable 0-90 degrees and takes measurements in 9 degree increments. Additionally, a shadow band allows measurement of the diffuse component of the radiation at each position. The electronic controls utilize an Arduino UNO microcontroller to synchronizes the movement of two PAP bipolar (stepper) motors with the activation of the spectrometer via an external trigger. The spectrometer was factory calibrated for wavelength and calibrated for absolute irradiance using a Sellarnet SL1-Cal light source. We present preliminary results from data taken March-June, 2013, and comment on implications for PV devices in Cochabamba.
Influence of Extraterrestrial Radiation on Radiation Portal Monitors
DOE Office of Scientific and Technical Information (OSTI.GOV)
Keller, Paul E.; Kouzes, Richard T.
2009-06-01
Cosmic radiation and solar flares can be a major source of background radiation at the Earth’s surface. This paper examines the relationship between extraterrestrial radiation and the detectable background in radiation portal monitors used for homeland security applications. Background radiation data from 13 radiation portal monitor facilities are examined and compared against external sources of data related to extraterrestrial radiation, including measurements at neutron monitors located at 53 cosmic-ray observatories around the Earth, four polar orbiting satellites, three geostationary satellites, ground-based geomagnetic field data from observatories around the Earth, a solar magnetic index, solar radio flux data, and sunspot activitymore » data. Four-years (January 2003 through December 2006) of data are used in this study, which include the latter part of Solar Cycle 23 as solar activity was on the decline. The analysis shows a significant relationship between some extraterrestrial radiation and the background detected in the radiation portal monitors. A demonstrable decline is shown in the average gamma ray and neutron background at the radiation portal monitors as solar activity declined over the period of the study.« less
The Austrian UV monitoring network
NASA Astrophysics Data System (ADS)
Blumthaler, Mario; Klotz, Barbara; Schwarzmann, Michael; Schreder, Josef
2017-02-01
The Austrian UV Monitoring network is operational since 1998 providing a large data set of erythemally weighted UV irradiance recorded with broadband UV biometer at 12 stations distributed all over Austria. In order to obtain high quality data all biometer are recalibrated once a year, the detectors are checked regularly for humidity and quality control is done routinely. The collected data are processed and then published on the website http://www.uv-index.at where the UV-Index of all measurement sites is presented in near real time together with a map of the distribution of the UV-Index over Austria. These UV-Index data together with measurements of global radiation and ozone levels from OMI are used to study long term trends for the stations of the monitoring network. Neither for all weather conditions nor for clear sky conditions is a statistically significant trend found for the UV-Index (with one exception) and for ozone. Furthermore, the radiation amplification factor (RAF) is determined experimentally from the power law correlation between UV-Index and ozone level for the site Innsbruck (577 m above sea level, 47.26°N, 11.38°E) for 19°solar elevation. A value of 0.91 ± 0.05 is found for the RAF for clear sky days with low ground albedo and a value of 1.03 ± 0.08 for days with high ground albedo (snow cover).
Increase in Efficiency of Use of Pedestrian Radiation Portal Monitors
NASA Astrophysics Data System (ADS)
Solovev, D. B.; Merkusheva, A. E.
2017-11-01
Most international airports in the world use radiation portal monitors (RPM) for primary radiation control organization. During the exploitation pedestrian radiation portal monitors operators (in the Russian Federation it is a special subdivision of customs officials) have certain problems related to the search of an ionizing radiation source causing the alarm signal of a radiation monitor. Radiation portal monitors at standard (factory) settings have to find out the illegal moving of the radioisotopes moved by physical persons passing through a controlled zone and having a steady radiation by the gamma or neutron channel. The problem is that recently the number of the ownerships who underwent treatment or medical diagnostics with the use of radio pharmaceuticals considerably increased, i.e,. ownerships represent such an ionizing radiation source. The operator of the radiation portal monitor has to define very quickly whether the ownership is a violator (takes unsolved radioisotopes illegally) or is just a patient of the clinic who underwent treatment/diagnostics with the use of radio pharmaceuticals. The research showing the radioisotopes which are most often used in the medical purposes are given in article, it is offered to use the new software developed by the authors allowing the operator of the radiation portal monitor to define the location of the ownership which has such ionizing radiation source by the activity of radiation similar to the radiation from radio pharmaceuticals.
Commissioning of the soft x-ray undulator beamline at the Siam Photon Laboratory
DOE Office of Scientific and Technical Information (OSTI.GOV)
Nakajima, Hideki, E-mail: hideki@slri.or.th; Chaichuay, Sarunyu; Sudmuang, Porntip
2016-07-27
The synchrotron radiation from the first undulator at the Siam Photon Laboratory was characterized with the photon beam position monitors (BPMs) and grating monochromator. The soft x-ray undulator beamline employs a varied line-spacing plane grating monochromator with three interchangeable gratings. Since 2010, the beamline has delivered photons with energy of 40-160 and 220-1040 eV at the resolving power of 10,000 for user services at the two end- stations that utilize the photoemission electron spectroscopy and microscopy techniques. The undulator power-density distributions measured by the 0.05-mm wire-scan BPM were in good agreement with those in simulation. The flux-density distributions were evaluatedmore » in the red-shift measurements, which identify the central cone of radiation and its distribution. Since 2014, the operation of the other insertion devices in the storage ring has started, and consequently bought about the increases in the emittance from 41 to 61 nm·rad and the coupling constant from 4 to 11%. The local electron-orbit correction greatly improved the alignment of the electron beam in the undulator section resulting in the improvements of the photon flux and harmonics peaks of the undulator radiation.« less
NASA Astrophysics Data System (ADS)
Brovchenko, Mariya; Duhamel, Isabelle; Dechenaux, Benjamin
2017-09-01
The present paper presents the study carried out in the frame of the DISCOMS project, which stands for "DIstributed Sensing for COrium Monitoring and Safety". This study concerns the calculation of the neutron and gamma radiations received by the considered instrumentation during the normal reactor operation as well as in case of a severe accident for the EPR reactor, outside the reactor pressure vessel and in the containment basemat. This paper summarizes the methods and hypotheses used for the particle transport simulation outside the vessel during normal reactor operation. The results of the simulations are then presented including the responses for distributed Optical Fiber Sensors (OFS), such as the gamma dose and the fast neutron fluence, and for Self Powered Neutron Detectors (SPNDs), namely the neutron and gamma spectra. Same responses are also evaluated for severe accident situations in order to design the SPNDs being sensitive to the both types of received neutron-gamma radiation. By contrast, fibers, involved as transducers in distributed OFS have to resist to the total radiation gamma dose and neutron fluence received during normal operation and the severe accident.
Yasui, Shojiro
2016-10-01
With respect to radiation protection for decontamination efforts involving radioactive fallout emitted by the accident at the Fukushima Daiichi Atomic Power Plant, new regulations were established and obligated employers to monitor, record, and store of workers' dose records, and to check their past dose records at the time of employment. However, cumulative doses may not be properly maintained if a worker declares incorrect values for past doses. In response, with facilitation from the Ministry of Health, Labour and Welfare, primary contractors of decontamination works decided to establish a central dose registration system. There are four major issues in the design of the system to be resolved, included the following: primary contractors (a) do not have a legal responsibility to perform dose control for subcontractors, (b) do not have the right to control decontamination sites, (c) often organize joint ventures, and (d) correspond to a wide range of ambient dose rates. To resolve the issues, requirements of the system included the following: (a) centralize the operation of radiation passbooks, which records past doses and the results of medical examinations to each worker; (b) develop a database system that could register all dose data and accept inquiry from primary contractors; (c) establish a permanent data storage system for transferred records; and (d) provide graded type of services that are appropriate to the risk of radiation exposure. The system started its operation in December 2013 and provided dose distributions in April and July 2015. The average yearly dose in 2014 was 0.7 mSv, which increased by 0.2 mSv from 0.5 mSv in 2012 and 2013. However, no cumulative dose from 2012-2014 exceeded 20 mSv, which was far below than the dose limits (100 mSv/5 years and 50 mSv/year). Although current dose distributions of decontamination workers were within appropriate levels, careful monitoring of dose distribution is necessary for preserving the proper implementation of radiation protection prescribed in the regulations.
NASA Astrophysics Data System (ADS)
Ibrahim, Maslina Mohd; Yussup, Nolida; Haris, Mohd Fauzi; Soh @ Shaari, Syirrazie Che; Azman, Azraf; Razalim, Faizal Azrin B. Abdul; Yapp, Raymond; Hasim, Harzawardi; Aslan, Mohd Dzul Aiman
2017-01-01
One of the applications for radiation detector is area monitoring which is crucial for safety especially at a place where radiation source is involved. An environmental radiation monitoring system is a professional system that combines flexibility and ease of use for data collection and monitoring. Nowadays, with the growth of technology, devices and equipment can be connected to the network and Internet to enable online data acquisition. This technology enables data from the area monitoring devices to be transmitted to any place and location directly and faster. In Nuclear Malaysia, area radiation monitor devices are located at several selective locations such as laboratories and radiation facility. This system utilizes an Ethernet as a communication media for data acquisition of the area radiation levels from radiation detectors and stores the data at a server for recording and analysis. This paper discusses on the design and development of website that enable all user in Nuclear Malaysia to access and monitor the radiation level for each radiation detectors at real time online. The web design also included a query feature for history data from various locations online. The communication between the server's software and web server is discussed in detail in this paper.
Bayesian modeling to assess populated areas impacted by radiation from Fukushima
NASA Astrophysics Data System (ADS)
Hultquist, C.; Cervone, G.
2017-12-01
Citizen-led movements producing spatio-temporal big data are increasingly important sources of information about populations that are impacted by natural disasters. Citizen science can be used to fill gaps in disaster monitoring data, in addition to inferring human exposure and vulnerability to extreme environmental impacts. As a response to the 2011 release of radiation from Fukushima, Japan, the Safecast project began collecting open radiation data which grew to be a global dataset of over 70 million measurements to date. This dataset is spatially distributed primarily where humans are located and demonstrates abnormal patterns of population movements as a result of the disaster. Previous work has demonstrated that Safecast is highly correlated in comparison to government radiation observations. However, there is still a scientific need to understand the geostatistical variability of Safecast data and to assess how reliable the data are over space and time. The Bayesian hierarchical approach can be used to model the spatial distribution of datasets and flexibly integrate new flows of data without losing previous information. This enables an understanding of uncertainty in the spatio-temporal data to inform decision makers on areas of high levels of radiation where populations are located. Citizen science data can be scientifically evaluated and used as a critical source of information about populations that are impacted by a disaster.
NASA Technical Reports Server (NTRS)
Deepak, Adarsh; Wang, Pi-Huan
1985-01-01
The research program is documented for developing space and ground-based remote sensing techniques performed during the period from December 15, 1977 to March 15, 1985. The program involved the application of sophisticated radiative transfer codes and inversion methods to various advanced remote sensing concepts for determining atmospheric constituents, particularly aerosols. It covers detailed discussions of the solar aureole technique for monitoring columnar aerosol size distribution, and the multispectral limb scattered radiance and limb attenuated radiance (solar occultation) techniques, as well as the upwelling scattered solar radiance method for determining the aerosol and gaseous characteristics. In addition, analytical models of aerosol size distribution and simulation studies of the limb solar aureole radiance technique and the variability of ozone at high altitudes during satellite sunrise/sunset events are also described in detail.
Non-uniform dose distributions in cranial radiation therapy
NASA Astrophysics Data System (ADS)
Bender, Edward T.
Radiation treatments are often delivered to patients with brain metastases. For those patients who receive radiation to the entire brain, there is a risk of long-term neuro-cognitive side effects, which may be due to damage to the hippocampus. In clinical MRI and CT scans it can be difficult to identify the hippocampus, but once identified it can be partially spared from radiation dose. Using deformable image registration we demonstrate a semi-automatic technique for obtaining an estimated location of this structure in a clinical MRI or CT scan. Deformable image registration is a useful tool in other areas such as adaptive radiotherapy, where the radiation oncology team monitors patients during the course of treatment and adjusts the radiation treatments if necessary when the patient anatomy changes. Deformable image registration is used in this setting, but there is a considerable level of uncertainty. This work represents one of many possible approaches at investigating the nature of these uncertainties utilizing consistency metrics. We will show that metrics such as the inverse consistency error correlate with actual registration uncertainties. Specifically relating to brain metastases, this work investigates where in the brain metastases are likely to form, and how the primary cancer site is related. We will show that the cerebellum is at high risk for metastases and that non-uniform dose distributions may be advantageous when delivering prophylactic cranial irradiation for patients with small cell lung cancer in complete remission.
Real-time detection of fast and thermal neutrons in radiotherapy with CMOS sensors.
Arbor, Nicolas; Higueret, Stephane; Elazhar, Halima; Combe, Rodolphe; Meyer, Philippe; Dehaynin, Nicolas; Taupin, Florence; Husson, Daniel
2017-03-07
The peripheral dose distribution is a growing concern for the improvement of new external radiation modalities. Secondary particles, especially photo-neutrons produced by the accelerator, irradiate the patient more than tens of centimeters away from the tumor volume. However the out-of-field dose is still not estimated accurately by the treatment planning softwares. This study demonstrates the possibility of using a specially designed CMOS sensor for fast and thermal neutron monitoring in radiotherapy. The 14 microns-thick sensitive layer and the integrated electronic chain of the CMOS are particularly suitable for real-time measurements in γ/n mixed fields. An experimental field size dependency of the fast neutron production rate, supported by Monte Carlo simulations and CR-39 data, has been observed. This dependency points out the potential benefits of a real-time monitoring of fast and thermal neutron during beam intensity modulated radiation therapies.
Ultraviolet laser beam monitor using radiation responsive crystals
McCann, Michael P.; Chen, Chung H.
1988-01-01
An apparatus and method for monitoring an ultraviolet laser beam includes disposing in the path of an ultraviolet laser beam a substantially transparent crystal that will produce a color pattern in response to ultraviolet radiation. The crystal is exposed to the ultraviolet laser beam and a color pattern is produced within the crystal corresponding to the laser beam intensity distribution therein. The crystal is then exposed to visible light, and the color pattern is observed by means of the visible light to determine the characteristics of the laser beam that passed through crystal. In this manner, a perpendicular cross sectional intensity profile and a longitudinal intensity profile of the ultraviolet laser beam may be determined. The observation of the color pattern may be made with forward or back scattered light and may be made with the naked eye or with optical systems such as microscopes and television cameras.
10 CFR 36.29 - Radiation monitors.
Code of Federal Regulations, 2011 CFR
2011-01-01
... 10 Energy 1 2011-01-01 2011-01-01 false Radiation monitors. 36.29 Section 36.29 Energy NUCLEAR REGULATORY COMMISSION LICENSES AND RADIATION SAFETY REQUIREMENTS FOR IRRADIATORS Design and Performance Requirements for Irradiators § 36.29 Radiation monitors. (a) Irradiators with automatic product conveyor...
10 CFR 36.29 - Radiation monitors.
Code of Federal Regulations, 2014 CFR
2014-01-01
... 10 Energy 1 2014-01-01 2014-01-01 false Radiation monitors. 36.29 Section 36.29 Energy NUCLEAR REGULATORY COMMISSION LICENSES AND RADIATION SAFETY REQUIREMENTS FOR IRRADIATORS Design and Performance Requirements for Irradiators § 36.29 Radiation monitors. (a) Irradiators with automatic product conveyor...
10 CFR 36.29 - Radiation monitors.
Code of Federal Regulations, 2010 CFR
2010-01-01
... 10 Energy 1 2010-01-01 2010-01-01 false Radiation monitors. 36.29 Section 36.29 Energy NUCLEAR REGULATORY COMMISSION LICENSES AND RADIATION SAFETY REQUIREMENTS FOR IRRADIATORS Design and Performance Requirements for Irradiators § 36.29 Radiation monitors. (a) Irradiators with automatic product conveyor...
10 CFR 36.29 - Radiation monitors.
Code of Federal Regulations, 2012 CFR
2012-01-01
... 10 Energy 1 2012-01-01 2012-01-01 false Radiation monitors. 36.29 Section 36.29 Energy NUCLEAR REGULATORY COMMISSION LICENSES AND RADIATION SAFETY REQUIREMENTS FOR IRRADIATORS Design and Performance Requirements for Irradiators § 36.29 Radiation monitors. (a) Irradiators with automatic product conveyor...
10 CFR 36.29 - Radiation monitors.
Code of Federal Regulations, 2013 CFR
2013-01-01
... 10 Energy 1 2013-01-01 2013-01-01 false Radiation monitors. 36.29 Section 36.29 Energy NUCLEAR REGULATORY COMMISSION LICENSES AND RADIATION SAFETY REQUIREMENTS FOR IRRADIATORS Design and Performance Requirements for Irradiators § 36.29 Radiation monitors. (a) Irradiators with automatic product conveyor...
NASA Astrophysics Data System (ADS)
Davoodi, F.; Shahabi, C.; Burdick, J.; Rais-Zadeh, M.; Menemenlis, D.
2014-12-01
The work had been funded by NASA HQ's office of Cryospheric Sciences Program. Recent observations of the Arctic have shown that sea ice has diminished drastically, consequently impacting the environment in the Arctic and beyond. Certain factors such as atmospheric anomalies, wind forces, temperature increase, and change in the distribution of cold and warm waters contribute to the sea ice reduction. However current measurement capabilities lack the accuracy, temporal sampling, and spatial coverage required to effectively quantify each contributing factor and to identify other missing factors. Addressing the need for new measurement capabilities for the new Arctic regime, we propose a game-changing in-situ Arctic-wide Distributed Mobile Monitoring system called Moball-buoy Network. Moball-buoy Network consists of a number of wind-propelled self-powered inflatable spheres referred to as Moball-buoys. The Moball-buoys are self-powered. They use their novel mechanical control and energy harvesting system to use the abundance of wind in the Arctic for their controlled mobility and energy harvesting. They are equipped with an array of low-power low-mass sensors and micro devices able to measure a wide range of environmental factors such as the ice conditions, chemical species wind vector patterns, cloud coverage, air temperature and pressure, electromagnetic fields, surface and subsurface water conditions, short- and long-wave radiations, bathymetry, and anthropogenic factors such as pollutions. The stop-and-go motion capability, using their novel mechanics, and the heads up cooperation control strategy at the core of the proposed distributed system enable the sensor network to be reconfigured dynamically according to the priority of the parameters to be monitored. The large number of Moball-buoys with their ground-based, sea-based, satellite and peer-to-peer communication capabilities would constitute a wireless mesh network that provides an interface for a global control system. This control system will ensure arctic-wide coverage, will optimize Moball-buoys monitoring efforts according to their available resources and the priority of local areas of high scientific value within the Arctic region. Moball-buoy Network is expected to be the first robust and persistent Arctic-wide environment monitoring system capable of providing reliable readings in near real time
NASA Astrophysics Data System (ADS)
Mochalov, V. A.; Firstov, P. P.; Cherneva, N. V.; Sannikov, D. V.; Akbashev, R. R.; Uvarov, V. N.; Shevtsov, B. M.; Druzhin, G. I.; Mochalova, A. V.
2017-11-01
In the region of the Northern group of volcanoes in Kamchatka peninsula, a distributed network is being planned to monitor the VLF range electromagnetic radiation and to locate the lightning strokes. It will allow the researchers to register weaker electromagnetic pulses from lightning strokes in comparison to the World Wide Lightning Location Network. The hardware-software complex of the network under construction is presented. The capabilities of the available and the developing hardware and software to investigate natural phenomena associated with lightning activity are described.
Space Radiation Risk Assessment for Future Lunar Missions
NASA Technical Reports Server (NTRS)
Kim, Myung-Hee Y.; Ponomarev, Artem; Atwell, Bill; Cucinotta, Francis A.
2007-01-01
For lunar exploration mission design, radiation risk assessments require the understanding of future space radiation environments in support of resource management decisions, operational planning, and a go/no-go decision. The future GCR flux was estimated as a function of interplanetary deceleration potential, which was coupled with the estimated neutron monitor rate from the Climax monitor using a statistical model. A probability distribution function for solar particle event (SPE) occurrence was formed from proton fluence measurements of SPEs occurred during the past 5 solar cycles (19-23). Large proton SPEs identified from impulsive nitrate enhancements in polar ice for which the fluences are greater than 2 10(exp 9) protons/sq cm for energies greater than 30 MeV, were also combined to extend the probability calculation for high level of proton fluences. The probability with which any given proton fluence level of a SPE will be exceeded during a space mission of defined duration was then calculated. Analytic energy spectra of SPEs at different ranks of the integral fluences were constructed over broad energy ranges extending out to GeV, and representative exposure levels were analyzed at those fluences. For the development of an integrated strategy for radiation protection on lunar exploration missions, effective doses at various points inside a spacecraft were calculated with detailed geometry models representing proposed transfer vehicle and habitat concepts. Preliminary radiation risk assessments from SPE and GCR were compared for various configuration concepts of radiation shelter in exploratory-class spacecrafts.
2016-05-31
UMKC-YIP-TR-2016 May 2016 Technical Report Prompt Neutron Spectrometry for Identification of SNM in Unknown Shielding...University of Missouri – Kansas City MSND: Micro-structured Neutron Detector HRM: Handheld Radiation Monitor PHS: Pulse Height Spectrum ANI: Active... Neutron Interrogation Distribution Statement A 6 Administrative Information and Acknowledgements Members of the University of Missouri
Quasi solution of radiation transport equation
DOE Office of Scientific and Technical Information (OSTI.GOV)
Pogosbekyan, L.R.; Lysov, D.A.
There is uncertainty with experimental data as well as with input data of theoretical calculations. The neutron distribution from the variational principle, which takes into account both theoretical and experimental data, is obtained to increase the accuracy and speed of neutronic calculations. The neutron imbalance in mesh cells and the discrepancy between experimentally measured and calculated functional of the neutron distribution are simultaneously minimized. A fast-working and simple-programming iteration method is developed to minimize the objective functional. The method can be used in the core monitoring and control system for (a) power distribution calculations, (b) in- and ex-core detector calibration,more » (c) macro-cross sections or isotope distribution correction by experimental data, and (d) core and detector diagnostics.« less
NASA Astrophysics Data System (ADS)
Fan, W. R.; Wang, H. X.
2010-11-01
Thoracic electrical impedance tomography (EIT) aims to reconstruct a cross-sectional image of the internal spatial distribution of conductivity from electrical measurements made by injecting small alternating currents via an electrode array placed on the surface of the thorax. It is a non-invasive, radiation-free monitoring technique. In this paper, true 3D thorax models with conductivity distribution or complex conductivity distribution under different ARDS conditions are built up in comparison with the 2.5D ones, and EIT-derived numeric indices are also employed for evaluation of the lung ventilation. The purpose of this paper is to study different effects of different thorax models with either conductivity or complex conductivity on the reconstructed images and ventilation indices.
ReactorHealth Physics operations at the NIST center for neutron research.
Johnston, Thomas P
2015-02-01
Performing health physics and radiation safety functions under a special nuclear material license and a research and test reactor license at a major government research and development laboratory encompasses many elements not encountered by industrial, general, or broad scope licenses. This article reviews elements of the health physics and radiation safety program at the NIST Center for Neutron Research, including the early history and discovery of the neutron, applications of neutron research, reactor overview, safety and security of radiation sources and radioactive material, and general health physics procedures. These comprise precautions and control of tritium, training program, neutron beam sample processing, laboratory audits, inventory and leak tests, meter calibration, repair and evaluation, radioactive waste management, and emergency response. In addition, the radiation monitoring systems will be reviewed including confinement building monitoring, ventilation filter radiation monitors, secondary coolant monitors, gaseous fission product monitors, gas monitors, ventilation tritium monitor, and the plant effluent monitor systems.
Radiation exposure from work-related medical X-rays at the Portsmouth Naval Shipyard.
Daniels, Robert D; Kubale, Travis L; Spitz, Henry B
2005-03-01
Previous analyses suggest that worker radiation dose may be significantly increased by routine occupational X-ray examinations. Medical exposures are investigated for 570 civilian workers employed at the Portsmouth Naval Shipyard (PNS) at Kittery, Maine. The research objective was to determine the radiation exposure contribution of work-related chest X-rays (WRX) relative to conventional workplace radiation sources. Methods were developed to estimate absorbed doses to the active (hematopoietic) bone marrow from X-ray examinations and workplace exposures using data extracted from worker dosimetry records (8,468) and health records (2,453). Dose distributions were examined for radiation and non-radiation workers. Photofluorographic chest examinations resulted in 82% of the dose from medical sources. Radiation workers received 26% of their collective dose from WRX and received 66% more WRX exposure than non-radiation workers. WRX can result in a significant fraction of the total dose, especially for radiation workers who were more likely to be subjected to routine medical monitoring. Omission of WRX from the total dose is a likely source of bias that can lead to dose category misclassification and may skew the epidemiologic dose-response assessment for cancers induced by the workplace.
GSM module for wireless radiation monitoring system via SMS
NASA Astrophysics Data System (ADS)
Rahman, Nur Aira Abd; Hisyam Ibrahim, Noor; Lombigit, Lojius; Azman, Azraf; Jaafar, Zainudin; Arymaswati Abdullah, Nor; Hadzir Patai Mohamad, Glam
2018-01-01
A customised Global System for Mobile communication (GSM) module is designed for wireless radiation monitoring through Short Messaging Service (SMS). This module is able to receive serial data from radiation monitoring devices such as survey meter or area monitor and transmit the data as text SMS to a host server. It provides two-way communication for data transmission, status query, and configuration setup. The module hardware consists of GSM module, voltage level shifter, SIM circuit and Atmega328P microcontroller. Microcontroller provides control for sending, receiving and AT command processing to GSM module. The firmware is responsible to handle task related to communication between device and host server. It process all incoming SMS, extract, and store new configuration from Host, transmits alert/notification SMS when the radiation data reach/exceed threshold value, and transmits SMS data at every fixed interval according to configuration. Integration of this module with radiation survey/monitoring device will create mobile and wireless radiation monitoring system with prompt emergency alert at high-level radiation.
A note on the tissue star dose in personnel radiation monitoring in space
NASA Technical Reports Server (NTRS)
Schaefer, H. J.
1978-01-01
Secondaries from nuclear interactions of high energy primaries in the body tissues themselves contribute substantially to the astronaut's radiation exposure in space. The so-called tissue star dose is assessed from the prong number distribution of disintegration stars in emulsion. Prong counts of 1,000 emulsion stars from the Apollo-Soyuz mission reported earlier were re-evaluated. The original scores were divided into sets of 250, 500, 750, and 1,000 emulsion stars and the respective prong number distributions established. The statistical error of the gelatin star number for the four consecutively larger was found to vary, on the 67 percent confidence level, from + or - 25 percent for the count of 250 emulsion stars to + or - 11 percent for 1,000 stars. Seen in the context of the other limitations of the experimental design, the lowest effort of prong-counting 250 stars appears entirely appropriate.
Ji, Young-Yong; Kim, Chang-Jong; Lim, Kyo-Sun; Lee, Wanno; Chang, Hyon-Sock; Chung, Kun Ho
2017-10-01
To expand the application of dose rate spectroscopy to the environment, the method using an environmental radiation monitor (ERM) based on a 3' × 3' NaI(Tl) detector was used to perform real-time monitoring of the dose rate and radioactivity for detected gamma nuclides in the ground around an ERM. Full-energy absorption peaks in the energy spectrum for dose rate were first identified to calculate the individual dose rates of Bi, Ac, Tl, and K distributed in the ground through interference correction because of the finite energy resolution of the NaI(Tl) detector used in an ERM. The radioactivity of the four natural radionuclides was then calculated from the in situ calibration factor-that is, the dose rate per unit curie-of the used ERM for the geometry of the ground in infinite half-space, which was theoretically estimated by Monte Carlo simulation. By an intercomparison using a portable HPGe and samples taken from the ground around an ERM, this method to calculate the dose rate and radioactivity of four nuclides using an ERM was experimentally verified and finally applied to remotely monitor them in real-time in the area in which the ERM had been installed.
2013-04-01
different ultrasonic and electromagnetic field modeling problems for NDE (nondestructive evaluation) applications [5- 14]. 2d . Use of the...transient ultrasonic wave propagation using the Distributed Point Source Method”, IEEE Transactions on Ultrasonics, Ferroelectric and Frequency Control...Cavity”, IEEE Transactions on Ultrasonics, Ferroelectric and Frequency Control, Vol. 57(6), pp. 1396-1404, 2010. [10] A. Shelke, S. Das and T. Kundu
Analytical & Experimental Study of Radio Frequency Cavity Beam Profile Monitor
DOE Office of Scientific and Technical Information (OSTI.GOV)
Balcazar, Mario D.; Yonehara, Katsuya
The purpose of this analytical and experimental study is multifold: 1) To explore a new, radiation-robust, hadron beam profile monitor for intense neutrino beam applications; 2) To test, demonstrate, and develop a novel gas-filled Radio-Frequency (RF) cavity to use in this monitoring system. Within this context, the first section of the study analyzes the beam distribution across the hadron monitor as well as the ion-production rate inside the RF cavity. Furthermore a more effecient pixel configuration across the hadron monitor is proposed to provide higher sensitivity to changes in beam displacement. Finally, the results of a benchtop test of themore » tunable quality factor RF cavity will be presented. The proposed hadron monitor configuration consists of a circular array of RF cavities located at a radial distance of 7cm { corresponding to the standard deviation of the beam due to scatering { and a gas-filled RF cavity with a quality factor in the range 400 - 800.« less
NASA Astrophysics Data System (ADS)
Li, Dong; Feng, Chi; Gao, Shan; Chen, Liwei; Daniel, Ketui
2018-06-01
Accurate measurement of gas turbine blade temperature is of great significance as far as blade health monitoring is concerned. An important method for measuring this temperature is the use of a radiation pyrometer. In this research, error of the pyrometer caused by reflected radiation from the surfaces surrounding the target and the emission angle of the target was analyzed. Important parameters for this analysis were the view factor between interacting surfaces, spectral directional emissivity, pyrometer operating wavelength and the surface temperature distribution on the blades and the vanes. The interacting surface of the rotor blade and the vane models used were discretized using triangular surface elements from which contour integral was used to calculate the view factor between the surface elements. Spectral directional emissivities were obtained from an experimental setup of Ni based alloy samples. A pyrometer operating wavelength of 1.6 μm was chosen. Computational fluid dynamics software was used to simulate the temperature distribution of the rotor blade and the guide vane based on the actual gas turbine input parameters. Results obtained in this analysis show that temperature error introduced by reflected radiation and emission angle ranges from ‑23 K to 49 K.
A survey of light-scattering techniques used in the remote monitoring of atmospheric aerosols
NASA Technical Reports Server (NTRS)
Deirmendjian, D.
1980-01-01
A critical survey of the literature on the use of light-scattering mechanisms in the remote monitoring of atmospheric aerosols, their geographical and spatial distribution, and temporal variations was undertaken to aid in the choice of future operational systems, both ground based and air or space borne. An evaluation, mainly qualitative and subjective, of various techniques and systems is carried out. No single system is found to be adequate for operational purposes. A combination of earth surface and space-borne systems based mainly on passive techniques involving solar radiation with active (lidar) systems to provide auxiliary or backup information is tentatively recommended.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Youn, H; Jeon, H; Nam, J
Purpose: To investigate the feasibility of an analytic framework to estimate patients’ absorbed dose distribution owing to daily cone-beam CT scan for image-guided radiation treatment. Methods: To compute total absorbed dose distribution, we separated the framework into primary and scattered dose calculations. Using the source parameters such as voltage, current, and bowtie filtration, for the primary dose calculation, we simulated the forward projection from the source to each voxel of an imaging object including some inhomogeneous inserts. Then we calculated the primary absorbed dose at each voxel based on the absorption probability deduced from the HU values and Beer’s law.more » In sequence, all voxels constructing the phantom were regarded as secondary sources to radiate scattered photons for scattered dose calculation. Details of forward projection were identical to that of the previous step. The secondary source intensities were given by using scatter-to- primary ratios provided by NIST. In addition, we compared the analytically calculated dose distribution with their Monte Carlo simulation results. Results: The suggested framework for absorbed dose estimation successfully provided the primary and secondary dose distributions of the phantom. Moreover, our analytic dose calculations and Monte Carlo calculations were well agreed each other even near the inhomogeneous inserts. Conclusion: This work indicated that our framework can be an effective monitor to estimate a patient’s exposure owing to cone-beam CT scan for image-guided radiation treatment. Therefore, we expected that the patient’s over-exposure during IGRT might be prevented by our framework.« less
Active personal radiation monitor for lunar EVA
NASA Astrophysics Data System (ADS)
Straume, Tore; Borak, Tom; Braby, L. A.; Lusby, Terry; Semones, Edward J.; Vazquez, Marcelo E.
As astronauts return to the Moon-and this time, work for extended periods-there will be a critical need for crew personnel radiation monitoring as they operate lunar rovers or otherwise perform a myriad of extravehicular activities (EVAs). Our focus is on development of a small personal radiation monitor for lunar EVA that responds to the complex radiation quality and changing dose rates on the Moon. Of particular concern are active monitoring capabilities that provide both early warning and radiation dosimetry information during solar particle events (SPEs). To accomplish this, we are developing small detectors integrated with modern high speed, low power microelectronics to measure dose-rate and dose-mean lineal energy in real time. The monitor is designed to perform over the range of dose rates and LETs expected from both GCR and SPE radiations during lunar EVA missions. The monitor design provides simultaneous measurement of dose-equivalent rates at two tissue-equivalent depths simulating skin and marrow. The compact personal monitor is estimated to be the size of a cell phone and would fit on an EVA spacesuit (e.g., in backpack) or in a toolbox. The four-year development effort (which began December 2007) will result in a prototype radiation monitor field tested and characterized for the major radiations expected on the surface of the Moon. We acknowledge support from NSBRI through grants to NASA Ames Research Center (T. Straume, PI) and Colorado State University (T. Borak, PI).
Use of Portal Monitors for Detection of Technogenic Radioactive Sources in Scrap Metal
NASA Astrophysics Data System (ADS)
Solovev, D. B.; Merkusheva, A. E.
2017-11-01
The article considers the features of organization of scrap-metal primary radiation control on the specialized enterprises engaging in its deep processing and storage at using by primary technical equipment - radiation portal monitors. The issue of this direction relevance, validity of radiation control implementation with the use of radiation portal monitors, physical and organizational bases of radiation control are considered in detail. The emphasis is put on the considerable increase in the number of technogenic radioactive sources detected in scrap-metal that results in the entering into exploitation of radioactive metallic structures as different building wares. One of reasons of such increase of the number of technogenic radioactive sources getting for processing with scrap-metal is the absence of any recommendations on the radiation portal monitors exploitation. The practical division of the article offers to recommendation on tuning of the modes of work of radiation portal monitors depending on influence the weather factor thus allowing to considerably increase the percent of technogenic radioactive sources detection.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Shapiro, J.
1976-02-01
The radiation exposure of airport workers handling shipments of radioactive materials was studied at six airports. Descriptions were obtained of the handling and arrangement of the packages, dose distributions were mapped around groupings of packages, and doses received by workers were evaluated both on the basis of time-motion studies and through readings of personal monitoring devices. Results of dosimeters worn over extended periods indicated that no workers were expected to receive exposures in excess of 500 millirems per year and most were expected to receive less than 100 millirems per year. No evidence was found in any of the sixmore » airport studies to suggest that members of the public received any exposure of significance relative to the natural background radiation.« less
[Experimental research on the electromagnetic radiation immunity of a kind of portable monitor].
Yuan, Jun; Xiao, Dongping; Jian, Xin
2010-11-01
The paper is focused on a kind of portable monitor that is widely used in military hospitals. In order to study the electromagnetic radiation immunity of the monitor, the experiments of electromagnetic radiation caused by radio frequency continuous wave in reverberation chamber and by ultra wide band (UWB) electromagnetic pulse have been done. The study results show that UWB electromagnetic pulse interferes observably the operating state of the monitor. It should be paid high attention to take protective measures. The monitor tested has some electromagnetic immunity ability for radio frequency continuous wave radiation. The frequent abnormal phenomena are baseline drift and waveform distortion. The electromagnetic sensitivity of the monitor is related to the frequency of interference source. The monitor tested is most sensitive to the frequency of 390 MHz.
Remote Sensing of Aerosol and Aerosol Radiative Forcing of Climate from EOS Terra MODIS Instrument
NASA Technical Reports Server (NTRS)
Kaufman, Yoram; Tanre, Didier; Remer, Lorraine; Einaudi, Franco (Technical Monitor)
2000-01-01
The recent launch of EOS-Terra into polar orbit has begun to revolutionize remote sensing of aerosol and their effect on climate. Terra has five instruments, two of them,Moderate Resolution Imaging Spectroradiometer (MODIS) and Multiangle Imaging Spectro-Radiometer (MISR) are designed to monitor global aerosol in two different complementary ways. Here we shall discuss the use of the multispectral measurements of MODIS to derive: (1) the global distribution of aerosol load (and optical thickness) over ocean and land; (2) to measure the impact of aerosol on reflection of sunlight to space; and (3) to measure the ability of aerosol to absorb solar radiation. These measurements have direct applications on the understanding of the effect of aerosol on climate, the ability to predict climate change, and on the monitoring of dust episodes and man-made pollution. Principles of remote sensing of aerosol from MODIS will be discussed and first examples of measurements from MODIS will be provided.
Radioactivity Risk Assessment of Radon and Gamma Dose at One Uranium Tailings Pond in China
NASA Astrophysics Data System (ADS)
Lou, Yalong; Liu, Yong; Peng, Guowen; Zhao, Guodong; Zhang, Yan; Yang, Zhu
2018-01-01
A year-long monitoring of gamma radiation effective dose rate and radon concentration had been done in the reservoir area of one uranium tailings pond in Hunan province (The monitoring area included indoor and outdoor area of residential buildings and workshops, tailings dam slope). Afterwards, the annual effective radiation dose of the people in that radiation environment had been calculated based on the results of monitoring, as well as a radiation risk assessment. According to the assessment, gamma radiation effective dose rate and radon concentration in the monitoring area were low, and the annual effective radiation dose was far below the international standard (30mSv), which showed that the radiation would not put the people’s health at risk. However, the annual effective radiation dose of gamma was far above that of radon in the area of uranium tailings pond; therefore, it’s advisable to take quarantine measures in in the area of uranium tailings pond to keep the surrounding residents away from unnecessary ionizing radiation.
2012-09-30
and Forecasting Based on Observations, Adaptive Sampling, and Numerical Prediction Steven R. Ramp Soliton Ocean Services, Inc. 691 Country Club... Soliton Ocean Services, Inc,691 Country Club Drive,Monterey,CA,93924 8. PERFORMING ORGANIZATION REPORT NUMBER 9. SPONSORING/MONITORING AGENCY NAME(S...shortwave. The results show that the incoming shortwave radiation was the dominant term, even when averaged over the dark hours, which accounts
Solar mesosphere explorer: Experiment description
NASA Technical Reports Server (NTRS)
1977-01-01
The Solar Mesosphere Explorer (SME) satellite experiments will provide a comprehensive study of atmospheric ozone and the processes which form and destroy it. Five instruments to be carried on the spacecraft will measure the ozone density and altitude distribution, monitor the incoming solar radiation, and measure other atmospheric constituents which affect ozone. The investigative approach concept, methods and procedures, preflight studies, and orbits and mission lifetime are presented. Descriptions of the instruments are also presented.
Koster, J.E.; Bolton, R.D.
1999-03-02
A radiation monitor for use with liquids that utilizes air ions created by alpha radiation emitted by the liquids as its detectable element. A signal plane, held at an electrical potential with respect to ground, collects these air ions. A guard plane or guard rings is used to limit leakage currents. In one embodiment, the monitor is used for monitoring liquids retained in a tank. Other embodiments monitor liquids flowing through a tank, and bodies of liquids, such as ponds, lakes, rivers and oceans. 4 figs.
Koster, James E.; Bolton, Richard D.
1999-01-01
A radiation monitor for use with liquids that utilizes air ions created by alpha radiation emitted by the liquids as its detectable element. A signal plane, held at an electrical potential with respect to ground, collects these air ions. A guard plane or guard rings is used to limit leakage currents. In one embodiment, the monitor is used for monitoring liquids retained in a tank. Other embodiments monitor liquids flowing through a tank, and bodies of liquids, such as ponds, lakes, rivers and oceans.
Historical Radiological Event Monitoring
During and after radiological events EPA's RadNet monitors the environment for radiation. EPA monitored environmental radiation levels during and after Chernobyl, Fukushima and other international and domestic radiological incidents.
Radiation Control on Uzbekistan Borders - Results and Perspectives
DOE Office of Scientific and Technical Information (OSTI.GOV)
Petrenko, Vitaliy; Yuldashev, Bekhzod; Ismailov, Ulughbek
2009-12-02
The measures and actions on prevention, detection and response to criminal or unauthorized acts involving radioactive materials in Uzbekistan are presented. In frames of program of radiation monitoring to prevent illicit trafficking of nuclear and radioactive materials main customs border checkpoints were equipped with commercial radiation portal monitors. Special radiation monitors elaborated and manufactured in INP AS RU are installed in INP(main gates, research reactor and laboratory building) to provide nuclear security of Institute facilities. The experience of Uzbekistan in establishing radiation monitoring systems on its borders, their operation and maintenance would be useful for realization of proposed plan ofmore » strengthening measures to prevent illicit trafficking in Republics of Central Asia region.« less
Yan, Aidong; Huang, Sheng; Li, Shuo; Chen, Rongzhang; Ohodnicki, Paul; Buric, Michael; Lee, Shiwoo; Li, Ming-Jun; Chen, Kevin P
2017-08-24
This paper reports a technique to enhance the magnitude and high-temperature stability of Rayleigh back-scattering signals in silica fibers for distributed sensing applications. With femtosecond laser radiation, more than 40-dB enhancement of Rayleigh backscattering signal was generated in silica fibers using 300-nJ laser pulses at 250 kHz repetition rate. The laser-induced Rayleigh scattering defects were found to be stable from the room temperature to 800 °C in hydrogen gas. The Rayleigh scatter at high temperatures was correlated to the formation and modification of nanogratings in the fiber core. Using optical fibers with enhanced Rayleigh backscattering profiles as distributed temperature sensors, we demonstrated real-time monitoring of solid oxide fuel cell (SOFC) operations with 5-mm spatial resolution at 800 °C. Information gathered by these fiber sensor tools can be used to verify simulation results or operated in a process-control system to improve the operational efficiency and longevity of SOFC-based energy generation systems.
NASA Astrophysics Data System (ADS)
Colins, Karen; Li, Liqian; Liu, Yu
2017-05-01
Mass production of widely used semiconductor digital integrated circuits (ICs) has lowered unit costs to the level of ordinary daily consumables of a few dollars. It is therefore reasonable to contemplate the idea of an engineered system that consumes unshielded low-cost ICs for the purpose of measuring gamma radiation dose. Underlying the idea is the premise of a measurable correlation between an observable property of ICs and radiation dose. Accumulation of radiation-damage-induced state changes or error events is such a property. If correct, the premise could make possible low-cost wide-area radiation dose measurement systems, instantiated as wireless sensor networks (WSNs) with unshielded consumable ICs as nodes, communicating error events to a remote base station. The premise has been investigated quantitatively for the first time in laboratory experiments and related analyses performed at the Canadian Nuclear Laboratories. State changes or error events were recorded in real time during irradiation of samples of ICs of different types in a 60Co gamma cell. From the error-event sequences, empirical distribution functions of dose were generated. The distribution functions were inverted and probabilities scaled by total error events, to yield plots of the relationship between dose and error tallies. Positive correlation was observed, and discrete functional dependence of dose quantiles on error tallies was measured, demonstrating the correctness of the premise. The idea of an engineered system that consumes unshielded low-cost ICs in a WSN, for the purpose of measuring gamma radiation dose over wide areas, is therefore tenable.
105KE Basin Area Radiation Monitor System (ARMS) Acceptance Test Procedure
DOE Office of Scientific and Technical Information (OSTI.GOV)
KINKEL, C.C.
1999-12-14
This procedure is intended for the Area Radiation Monitoring System, ARMS, that is replacing the existing Programmable Input-Output Processing System, PIOPS, radiation monitoring system in the 105KE basin. The new system will be referred to as the 105KE ARMS, 105KE Area Radiation Monitoring System. This ATP will ensure calibration integrity of the 105KE radiation detector loops. Also, this ATP will test and document the display, printing, alarm output, alarm acknowledgement, upscale check, and security functions. This ATP test is to be performed after completion of the 105KE ARMS installation. The alarm outputs of the 105KE ARMS will be connected tomore » the basin detector alarms, basin annunciator system, and security Alarm Monitoring System, AMS, located in the 200 area Central Alarm Station (CAS).« less
This report covers the routine radiation monitoring activities conducted by the Environmental Monitoring Systems Laboratory-Las Vegas in areas which may be affected by nuclear testing programs of the Department of Energy. This monitoring is conducted to document compliance with s...
This report covers the routine radiation monitoring activities conducted by the Environmental Monitoring Systems Laboratory-Las Vegas in areas which may be affected by nuclear testing programs of the Department of Energy. This monitoring is conducted to document compliance with s...
This report covers the routine radiation monitoring activities conducted by the Environmental Monitoring Systems Laboratory-Las Vegas in areas which may be affected by nuclear testing programs of the Department of Energy. This monitoring is conducted to document compliance with s...
NASA Astrophysics Data System (ADS)
Yussup, F.; Ibrahim, M. M.; Haris, M. F.; Soh, S. C.; Hasim, H.; Azman, A.; Razalim, F. A. A.; Yapp, R.; Ramli, A. A. M.
2016-01-01
With the growth of technology, many devices and equipments can be connected to the network and internet to enable online data acquisition for real-time data monitoring and control from monitoring devices located at remote sites. Centralized radiation monitoring system (CRMS) is a system that enables area radiation level at various locations in Malaysian Nuclear Agency (Nuklear Malaysia) to be monitored centrally by using a web browser. The Local Area Network (LAN) in Nuclear Malaysia is utilized in CRMS as a communication media for data acquisition of the area radiation levels from radiation detectors. The development of the system involves device configuration, wiring, network and hardware installation, software and web development. This paper describes the software upgrading on the system server that is responsible to acquire and record the area radiation readings from the detectors. The recorded readings are called in a web programming to be displayed on a website. Besides the main feature which is acquiring the area radiation levels in Nuclear Malaysia centrally, the upgrading involves new features such as uniform time interval for data recording and exporting, warning system and dose triggering.
Emitted short wavelength infrared radiation for detection and monitoring of volcanic activity
NASA Technical Reports Server (NTRS)
Rothery, D. A.; Francis, P. W.; Wood, C. A.
1988-01-01
Thematic Mapper images from LANDSAT were used to monitor volcanoes. Achievements include: (1) the discovery of a magmatic precursor to the 16 Sept. 1986 eruption of Lascar, northern Chile, on images from Mar. and July 1985 and of continuing fumarolic activity after the eruption; (2) the detection of unreported major changes in the distribution of lava lakes on Erta'Ale, Ethiopia; and (3) the mapping of a halo of still-hot spatter surrounding a vent on Mount Erebus, Antarctica, on an image acquired 5 min after a minor eruption otherwise known only from seismic records. A spaceborne short wavelength infrared sensor for observing hot phenomena of volcanoes is proposed. A polar orbit is suggested.
Searching for O-X-B mode-conversion window with monitoring of stray microwave radiation in LHD
NASA Astrophysics Data System (ADS)
Igami, H.; Kubo, S.; Laqua, H. P.; Nagasaki, K.; Inagaki, S.; Notake, T.; Shimozuma, T.; Yoshimura, Y.; Mutoh, T.; LHD Experimental Group
2006-10-01
In the Large Helical Device, the stray microwave radiation is monitored by using so-called sniffer probes during electron cyclotron heating. In monitoring the stray radiation, we changed the microwave beam injection angle and search the O-X-B mode-conversion window to excite electron Bernstein waves (EBWs). When the microwave beam is injected toward the vicinity of the predicted O-X-B mode-conversion window, the electron temperature rises in the central part of overdense plasmas. In that case, the stray radiation level near the injection antenna becomes low. These results indicate that monitoring the stray radiation near the injection antenna is helpful in confirming the effectiveness of excitation of EBWs simply without precise analysis.
Retrospective study of the iodine-131 contamination of workers in the radiopharmaceutical industry.
Gaburo, J C; Lipsztein, J L; Rabelo, D M; Stabin, M
2003-01-01
A dose reconstruction study was performed for personnel occupationally exposed to 131I in radiopharmaceutical production, during the years 1981 to 1994, with the objective of estimating committed effective doses and critically reviewing the main causes of their exposures. The workers were selected from a group responsible for the production, labelling and distribution of all radiopharmaceutical material in Brazil. Best estimates of intakes and doses were derived from the examination of the individual monitoring records and the reports from the radiation protection supervisor, complemented by interviews with the workers and with radiation protection officers. Over this time period workers had chronic as well as acute intakes of 131I. Committed effective doses were found to be dependent on the task performed by the worker and the site of operation and inversely correlated with the amounts of iodine handled. Intakes in general were a consequence of inadequate radiation protection control.
High-intensity power-resolved radiation imaging of an operational nuclear reactor.
Beaumont, Jonathan S; Mellor, Matthew P; Villa, Mario; Joyce, Malcolm J
2015-10-09
Knowledge of the neutron distribution in a nuclear reactor is necessary to ensure the safe and efficient burnup of reactor fuel. Currently these measurements are performed by in-core systems in what are extremely hostile environments and in most reactor accident scenarios it is likely that these systems would be damaged. Here we present a compact and portable radiation imaging system with the ability to image high-intensity fast-neutron and gamma-ray fields simultaneously. This system has been deployed to image radiation fields emitted during the operation of a TRIGA test reactor allowing a spatial visualization of the internal reactor conditions to be obtained. The imaged flux in each case is found to scale linearly with reactor power indicating that this method may be used for power-resolved reactor monitoring and for the assay of ongoing nuclear criticalities in damaged nuclear reactors.
High-intensity power-resolved radiation imaging of an operational nuclear reactor
Beaumont, Jonathan S.; Mellor, Matthew P.; Villa, Mario; Joyce, Malcolm J.
2015-01-01
Knowledge of the neutron distribution in a nuclear reactor is necessary to ensure the safe and efficient burnup of reactor fuel. Currently these measurements are performed by in-core systems in what are extremely hostile environments and in most reactor accident scenarios it is likely that these systems would be damaged. Here we present a compact and portable radiation imaging system with the ability to image high-intensity fast-neutron and gamma-ray fields simultaneously. This system has been deployed to image radiation fields emitted during the operation of a TRIGA test reactor allowing a spatial visualization of the internal reactor conditions to be obtained. The imaged flux in each case is found to scale linearly with reactor power indicating that this method may be used for power-resolved reactor monitoring and for the assay of ongoing nuclear criticalities in damaged nuclear reactors. PMID:26450669
Operational surface UV radiation product from GOME-2 and AVHRR/3 data
NASA Astrophysics Data System (ADS)
Kujanpää, J.; Kalakoski, N.
2015-05-01
The surface ultraviolet (UV) radiation product, version 1.20, generated operationally in the framework of the Satellite Application Facility on Ozone and Atmospheric Chemistry Monitoring (O3M SAF) of the European Organisation for the Exploitation of Meteorological Satellites (EUMETSAT) is described. The product is based on the total ozone column derived from the measurements of the second Global Ozone Monitoring Experiment (GOME-2) instrument aboard EUMETSAT's polar orbiting meteorological operational (Metop) satellites. The input total ozone product is generated by the German Aerospace Center (DLR) also within the O3M SAF framework. Polar orbiting satellites provide global coverage but infrequent sampling of the diurnal cloud cover. The diurnal variation of the surface UV radiation is extremely strong due to modulation by solar elevation and rapidly changing cloud cover. At the minimum, one sample of the cloud cover in the morning and another in the afternoon are needed to derive daily maximum and daily integrated surface UV radiation quantities. This is achieved by retrieving cloud optical depth from the channel 1 reflectance of the third Advanced Very High Resolution Radiometer (AVHRR/3) instrument aboard both Metop in the morning orbit (daytime descending node around 09:30 LT) and Polar Orbiting Environmental Satellites (POES) of the National Oceanic and Atmospheric Administration (NOAA) in the afternoon orbit (daytime ascending node around 14:30 LT). In addition, more overpasses are used at high latitudes where the swaths of consecutive orbits overlap. The input satellite data are received from EUMETSAT's Multicast Distribution System (EUMETCast) using commercial telecommunication satellites for broadcasting the data to the user community. The surface UV product includes daily maximum dose rates and integrated daily doses with different biological weighting functions, integrated UVB and UVA radiation, solar noon UV Index and daily maximum photolysis frequencies of ozone and nitrogen dioxide at the surface level. The quantities are computed in a 0.5° × 0.5° regular latitude-longitude grid and stored as daily files in the hierarchical data format (HDF5) within two weeks from sensing. The product files are archived in the O3M SAF distributed archive and can be ordered via the EUMETSAT Data Centre.
Resistance of Marine Bacterioneuston to Solar Radiation
Agogué, Hélène; Joux, Fabien; Obernosterer, Ingrid; Lebaron, Philippe
2005-01-01
A total of 90 bacterial strains were isolated from the sea surface microlayer (i.e., bacterioneuston) and underlying waters (i.e., bacterioplankton) from two sites of the northwestern Mediterranean Sea. The strains were identified by sequence analysis, and growth recovery was investigated after exposure to simulated solar radiation. Bacterioneuston and bacterioplankton isolates were subjected to six different exposure times, ranging from 0.5 to 7 h of simulated noontime solar radiation. Following exposure, the growth of each isolate was monitored, and different classes of resistance were determined according to the growth pattern. Large interspecific differences among the 90 marine isolates were observed. Medium and highly resistant strains accounted for 41% and 22% of the isolates, respectively, and only 16% were sensitive strains. Resistance to solar radiation was equally distributed within the bacterioneuston and bacterioplankton. Relative contributions to the highly resistant class were 43% for γ-proteobacteria and 14% and 8% for α-proteobacteria and the Cytophaga/Flavobacterium/Bacteroides (CFB) group, respectively. Within the γ-proteobacteria, the Pseudoalteromonas and Alteromonas genera appeared to be highly resistant to solar radiation. The majority of the CFB group (76%) had medium resistance. Our study further provides evidence that pigmented bacteria are not more resistant to solar radiation than nonpigmented bacteria. PMID:16151115
Kruse, Lyle W.
1985-01-01
A portal radiation monitor combines 0.1% FAR with high sensitivity to special nuclear material. The monitor utilizes pulse shape discrimination, dynamic compression of the photomultiplier output and scintillators sized to maintain efficiency over the entire portal area.
Kruse, L.W.
1982-03-23
A portal radiation monitor combines .1% FAR with high sensitivity to special nuclear material. The monitor utilizes pulse shape discrimination, dynamic compression of the photomultiplier output and scintillators sized to maintain efficiency over the entire portal area.
Variability of Earth's radiation budget components during 2009 - 2015 from radiometer IKOR-M data
NASA Astrophysics Data System (ADS)
Cherviakov, Maksim
2016-04-01
This report describes a new «Meteor-M» satellite program which has been started in Russia. The first satellite of new generation "Meteor-M» № 1 was put into orbit in September, 2009. The radiometer IKOR-M - «The Measuring instrument of short-wave reflected radiation" was created in Saratov State University. It was installed on Russian hydrometeorological satellites «Meteor-M» № 1 and № 2. Radiometer IKOR-M designed for satellite monitoring of the outgoing reflected short-wave radiation, which is one of the components of Earth's radiation budget. Such information can be used in different models of long-term weather forecasts, in researches of climate change trends and also in calculation of absorbed solar radiation values and albedo of the Earth-atmosphere system. Satellite «Meteor-M» № 1 and № 2 are heliosynchronous that allows observing from North to South Poles. The basic products of data processing are given in the form of global maps of distribution outgoing short-wave radiation (OSR), albedo and absorbed solar radiation (ASR). Such maps were made for each month during observation period. The IKOR-M product archive is available online at all times. A searchable catalogue of data products is continually updated and users may search and download data products via the Earth radiation balance components research laboratory website (http://www.sgu.ru/structure/geographic/metclim/balans) as soon as they become available. Two series of measurements from two different IKOR-M are available. The first radiometer had worked from October, 2009 to August, 2014 and second - from August, 2014 to the present. Therefore, there is a period when both radiometers work at the same time. Top-of-atmosphere fluxes deduced from the «Meteor-M» № 1 measurements in August, 2014 show very good agreement with the fluxes determined from «Meteor-M» № 2. The seasonal and interannual variations of OSR, albedo and ASR were discussed. The variations between SW radiation budget components seem to be within observational uncertainty and natural variability governed by cloudiness, water vapor and aerosol variations. It was assessed spatial and temporal variations of albedo and the absorbed solar radiation over different regions. Latitudinal distributions of albedo and ASR were estimated in more detail. Meridional cross sections over oceans and land were used separately for this estimation. It was shown that the albedo and ASR data received from the radiometer IKOR-M can be used to detect El Nino in the Pacific Ocean and monitoring of the East Asian Summer Monsoon. The report will be presented more detailed results. The reported study was funded by RFBR according to the research project No.16-35-00284 mol_a.
Wide-range radiation dose monitor
Kopp, Manfred K.
1986-01-01
A radiation dose-rate monitor is provided which operates in a conventional linear mode for radiation in the 0 to 0.5 R/h range and utilizes a nonlinear mode of operation for sensing radiation from 0.5 R/h to over 500 R/h. The nonlinear mode is achieved by a feedback circuit which adjusts the high voltage bias of the proportional counter, and hence its gas gain, in accordance with the amount of radiation being monitored. This allows compression of readout onto a single scale over the range of 0 to greater than 500 R/h without scale switching operations.
Wide-range radiation dose monitor
Kopp, M.K.
1984-09-20
A radiation dose-rate monitor is provided which operates in a conventional linear mode for radiation in the 0 to 0.5 R/h range and utilizes a nonlinear mode of operation for sensing radiation from 0.5 R/h to over 500 R/h. The nonlinear mode is achieved by a feedback circuit which adjusts the high voltage bias of the proportional counter, and hence its gas gain, in accordance with the amount of radiation being monitored. This allows compression of readout onto a single scale over the range of 0 to greater than 500 R/h without scale switching operations.
TH-E-209-00: Radiation Dose Monitoring and Protocol Management
DOE Office of Scientific and Technical Information (OSTI.GOV)
NONE
Radiation dose monitoring solutions have opened up new opportunities for medical physicists to be more involved in modern clinical radiology practices. In particular, with the help of comprehensive radiation dose data, data-driven protocol management and informed case follow up are now feasible. Significant challenges remain however and the problems faced by medical physicists are highly heterogeneous. Imaging systems from multiple vendors and a wide range of vintages co-exist in the same department and employ data communication protocols that are not fully standardized or implemented making harmonization complex. Many different solutions for radiation dose monitoring have been implemented by imaging facilitiesmore » over the past few years. Such systems are based on commercial software, home-grown IT solutions, manual PACS data dumping, etc., and diverse pathways can be used to bring the data to impact clinical practice. The speakers will share their experiences with creating or tailoring radiation dose monitoring/management systems and procedures over the past few years, which vary significantly in design and scope. Topics to cover: (1) fluoroscopic dose monitoring and high radiation event handling from a large academic hospital; (2) dose monitoring and protocol optimization in pediatric radiology; and (3) development of a home-grown IT solution and dose data analysis framework. Learning Objectives: Describe the scope and range of radiation dose monitoring and protocol management in a modern radiology practice Review examples of data available from a variety of systems and how it managed and conveyed. Reflect on the role of the physicist in radiation dose awareness.« less
Bayesian analyses of time-interval data for environmental radiation monitoring.
Luo, Peng; Sharp, Julia L; DeVol, Timothy A
2013-01-01
Time-interval (time difference between two consecutive pulses) analysis based on the principles of Bayesian inference was investigated for online radiation monitoring. Using experimental and simulated data, Bayesian analysis of time-interval data [Bayesian (ti)] was compared with Bayesian and a conventional frequentist analysis of counts in a fixed count time [Bayesian (cnt) and single interval test (SIT), respectively]. The performances of the three methods were compared in terms of average run length (ARL) and detection probability for several simulated detection scenarios. Experimental data were acquired with a DGF-4C system in list mode. Simulated data were obtained using Monte Carlo techniques to obtain a random sampling of the Poisson distribution. All statistical algorithms were developed using the R Project for statistical computing. Bayesian analysis of time-interval information provided a similar detection probability as Bayesian analysis of count information, but the authors were able to make a decision with fewer pulses at relatively higher radiation levels. In addition, for the cases with very short presence of the source (< count time), time-interval information is more sensitive to detect a change than count information since the source data is averaged by the background data over the entire count time. The relationships of the source time, change points, and modifications to the Bayesian approach for increasing detection probability are presented.
Canadian radiation belt science in the ILWS era
NASA Astrophysics Data System (ADS)
Mann, I. R.
The Outer Radiation Belt Injection, Transport, Acceleration, and Loss Satellite (ORBITALS) is a Canadian Space Agency small satellite mission proposed as a Canadian contribution to the satellite infrastructure for the International Living With a Star (ILWS) program. Planned to operate contemporaneously with the NASA Radiation Belt Storm Probes (RBSP), the ORBITALS will monitor the energetic electron and ion populations in the inner magnetosphere across a wide range of energies (keV to tens of MeV) as well as the dynamic electric and magnetic fields, waves, and cold plasma environment which govern the injection, transport, acceleration and loss of these energetic and space weather critical particle populations in the inner magnetosphere. Currently in Phase A Design Study, the ORBITALS will be launched into a low-inclination GTO-like orbit which every second orbit maximizes the long lasting apogee-pass conjunctions with both the ground-based instruments of the Canadian Geospace Monitoring (CGSM) array as well as with the GOES East and West and geosynchronous communications satellites in the North American sector. In a twelve-hour orbit, every second apogee will conjunct with instrumentation 180 degree in longitude away in the Asian sector. Specifically, the ORBITALS will make the measurements necessary to reach reveal fundamental new understanding of the relative importance of different physical processes (for example VLF verses ULF waves) which shape the energetic particle populations in the inner magnetosphere, as well as providing the raw radiation measurements at MEO altitudes necessary for the development of the next-generation of radiation belt specification models. On-board experiments will also monitor the dose, single event upset, and deep-dielectric charging responses of electronic components on-orbit. Supporting ground-based measurements of ULF and higher frequency wave fields from the Canadian CARISMA (www.carisma.ca) magnetometer array, as well as from other distributed networks of ground-based instrumentation will also be critical for reaching science closure. This paper outlines the radiation belt science targets for the ORBITALS mission, and describe how the ORBITALS can provide an essential complement to other proposed inner magnetospheric missions in the ILWS era.
10 CFR 835.703 - Other monitoring records.
Code of Federal Regulations, 2012 CFR
2012-01-01
... 10 Energy 4 2012-01-01 2012-01-01 false Other monitoring records. 835.703 Section 835.703 Energy DEPARTMENT OF ENERGY OCCUPATIONAL RADIATION PROTECTION Records § 835.703 Other monitoring records. The following information shall be documented and maintained: (a) Results of monitoring for radiation and...
10 CFR 835.703 - Other monitoring records.
Code of Federal Regulations, 2011 CFR
2011-01-01
... 10 Energy 4 2011-01-01 2011-01-01 false Other monitoring records. 835.703 Section 835.703 Energy DEPARTMENT OF ENERGY OCCUPATIONAL RADIATION PROTECTION Records § 835.703 Other monitoring records. The following information shall be documented and maintained: (a) Results of monitoring for radiation and...
10 CFR 835.703 - Other monitoring records.
Code of Federal Regulations, 2013 CFR
2013-01-01
... 10 Energy 4 2013-01-01 2013-01-01 false Other monitoring records. 835.703 Section 835.703 Energy DEPARTMENT OF ENERGY OCCUPATIONAL RADIATION PROTECTION Records § 835.703 Other monitoring records. The following information shall be documented and maintained: (a) Results of monitoring for radiation and...
10 CFR 835.703 - Other monitoring records.
Code of Federal Regulations, 2014 CFR
2014-01-01
... 10 Energy 4 2014-01-01 2014-01-01 false Other monitoring records. 835.703 Section 835.703 Energy DEPARTMENT OF ENERGY OCCUPATIONAL RADIATION PROTECTION Records § 835.703 Other monitoring records. The following information shall be documented and maintained: (a) Results of monitoring for radiation and...
Distributed Optical Fiber Sensors Based on Optical Frequency Domain Reflectometry: A review
Wang, Chenhuan; Liu, Kun; Jiang, Junfeng; Yang, Di; Pan, Guanyi; Pu, Zelin; Liu, Tiegen
2018-01-01
Distributed optical fiber sensors (DOFS) offer unprecedented features, the most unique one of which is the ability of monitoring variations of the physical and chemical parameters with spatial continuity along the fiber. Among all these distributed sensing techniques, optical frequency domain reflectometry (OFDR) has been given tremendous attention because of its high spatial resolution and large dynamic range. In addition, DOFS based on OFDR have been used to sense many parameters. In this review, we will survey the key technologies for improving sensing range, spatial resolution and sensing performance in DOFS based on OFDR. We also introduce the sensing mechanisms and the applications of DOFS based on OFDR including strain, stress, vibration, temperature, 3D shape, flow, refractive index, magnetic field, radiation, gas and so on. PMID:29614024
Distributed Optical Fiber Sensors Based on Optical Frequency Domain Reflectometry: A review.
Ding, Zhenyang; Wang, Chenhuan; Liu, Kun; Jiang, Junfeng; Yang, Di; Pan, Guanyi; Pu, Zelin; Liu, Tiegen
2018-04-03
Distributed optical fiber sensors (DOFS) offer unprecedented features, the most unique one of which is the ability of monitoring variations of the physical and chemical parameters with spatial continuity along the fiber. Among all these distributed sensing techniques, optical frequency domain reflectometry (OFDR) has been given tremendous attention because of its high spatial resolution and large dynamic range. In addition, DOFS based on OFDR have been used to sense many parameters. In this review, we will survey the key technologies for improving sensing range, spatial resolution and sensing performance in DOFS based on OFDR. We also introduce the sensing mechanisms and the applications of DOFS based on OFDR including strain, stress, vibration, temperature, 3D shape, flow, refractive index, magnetic field, radiation, gas and so on.
Using ACIS on the Chandra X-ray Observatory as a Particle Radiation Monitor II
NASA Technical Reports Server (NTRS)
Grant, C. E.; Ford, P. G.; Bautz, M. W.; ODell, S. L.
2012-01-01
The Advanced CCD Imaging Spectrometer is an instrument on the Chandra X-ray Observatory. CCDs are vulnerable to radiation damage, particularly by soft protons in the radiation belts and solar storms. The Chandra team has implemented procedures to protect ACIS during high-radiation events including autonomous protection triggered by an on-board radiation monitor. Elevated temperatures have reduced the effectiveness of the on-board monitor. The ACIS team has developed an algorithm which uses data from the CCDs themselves to detect periods of high radiation and a flight software patch to apply this algorithm is currently active on-board the instrument. In this paper, we explore the ACIS response to particle radiation through comparisons to a number of external measures of the radiation environment. We hope to better understand the efficiency of the algorithm as a function of the flux and spectrum of the particles and the time-profile of the radiation event.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Yussup, F., E-mail: nolida@nm.gov.my; Ibrahim, M. M., E-mail: maslina-i@nm.gov.my; Soh, S. C.
With the growth of technology, many devices and equipments can be connected to the network and internet to enable online data acquisition for real-time data monitoring and control from monitoring devices located at remote sites. Centralized radiation monitoring system (CRMS) is a system that enables area radiation level at various locations in Malaysian Nuclear Agency (Nuklear Malaysia) to be monitored centrally by using a web browser. The Local Area Network (LAN) in Nuclear Malaysia is utilized in CRMS as a communication media for data acquisition of the area radiation levels from radiation detectors. The development of the system involves devicemore » configuration, wiring, network and hardware installation, software and web development. This paper describes the software upgrading on the system server that is responsible to acquire and record the area radiation readings from the detectors. The recorded readings are called in a web programming to be displayed on a website. Besides the main feature which is acquiring the area radiation levels in Nuclear Malaysia centrally, the upgrading involves new features such as uniform time interval for data recording and exporting, warning system and dose triggering.« less
Boice, John D; Leggett, Richard W; Ellis, Elizabeth Dupree; Wallace, Phillip W; Mumma, Michael; Cohen, Sarah S; Brill, A Bertrand; Chadda, Bandana; Boecker, Bruce B; Yoder, R Craig; Eckerman, Keith F
2006-05-01
Incomplete radiation exposure histories, inadequate treatment of internally deposited radionuclides, and failure to account for neutron exposures can be important uncertainties in epidemiologic studies of radiation workers. Organ-specific doses from lifetime occupational exposures and radionuclide intakes were estimated for an epidemiologic study of 5,801 Rocketdyne/Atomics International (AI) radiation workers engaged in nuclear technologies between 1948 and 1999. The entire workforce of 46,970 Rocketdyne/AI employees was identified from 35,042 Kardex work histories cards, 26,136 electronic personnel listings, and 14,189 radiation folders containing individual exposure histories. To obtain prior and subsequent occupational exposure information, the roster of all workers was matched against nationwide dosimetry files from the Department of Energy, the Nuclear Regulatory Commission, the Landauer dosimetry company, the U.S. Army, and the U.S. Air Force. Dosimetry files of other worker studies were also accessed. Computation of organ doses from radionuclide intakes was complicated by the diversity of bioassay data collected over a 40-y period (urine and fecal samples, lung counts, whole-body counts, nasal smears, and wound and incident reports) and the variety of radionuclides with documented intake including isotopes of uranium, plutonium, americium, calcium, cesium, cerium, zirconium, thorium, polonium, promethium, iodine, zinc, strontium, and hydrogen (tritium). Over 30,000 individual bioassay measurements, recorded on 11 different bioassay forms, were abstracted. The bioassay data were evaluated using ICRP biokinetic models recommended in current or upcoming ICRP documents (modified for one inhaled material to reflect site-specific information) to estimate annual doses for 16 organs or tissues taking into account time of exposure, type of radionuclide, and excretion patterns. Detailed internal exposure scenarios were developed and annual internal doses were derived on a case-by-case basis for workers with committed equivalent doses indicated by screening criteria to be greater than 10 mSv to the organ with the highest internal dose. Overall, 5,801 workers were monitored for radiation at Rocketdyne/AI: 5,743 for external exposure and 2,232 for internal intakes of radionuclides; 41,169 workers were not monitored for radiation. The mean cumulative external dose based on Rocketdyne/AI records alone was 10.0 mSv, and the dose distribution was highly skewed with most workers experiencing low cumulative doses and only a few with high doses (maximum 500 mSv). Only 45 workers received greater than 200 mSv while employed at Rocketdyne/AI. However, nearly 32% (or 1,833) of the Rocketdyne/AI workers had been monitored for radiation at other nuclear facilities and incorporation of these doses increased the mean dose to 13.5 mSv (maximum 1,005 mSv) and the number of workers with >200 mSv to 69. For a small number of workers (n=292), lung doses from internal radionuclide intakes were relatively high (mean 106 mSv; maximum 3,560 mSv) and increased the overall population mean dose to 19.0 mSv and the number of workers with lung dose>200 mSv to 109. Nearly 10% of the radiation workers (584) were monitored for neutron exposures (mean 1.2 mSv) at Rocketdyne/AI, and another 2% were monitored for neutron exposures elsewhere. Interestingly, 1,477 workers not monitored for radiation at Rocketdyne/AI (3.6%) were found to have worn dosimeters at other nuclear facilities (mean external dose of 2.6 mSv, maximum 188 mSv). Without considering all sources of occupational exposure, an incorrect characterization of worker exposure would have occurred with the potential to bias epidemiologic results. For these pioneering workers in the nuclear industry, 26.5% of their total occupational dose (collective dose) was received at other facilities both prior to and after employment at Rocketdyne/AI. In addition, a small number of workers monitored for internal radionuclides contributed disproportionately to the number of workers with high lung doses. Although nearly 12% of radiation workers had been monitored for neutron exposures during their career, the cumulative dose levels were small in comparison with other external and internal exposure. Risk estimates based on nuclear worker data must be interpreted cautiously if internally deposited radionuclides and occupational doses received elsewhere are not considered.
Code of Federal Regulations, 2014 CFR
2014-01-01
... internal occupational dose. 20.1502 Section 20.1502 Energy NUCLEAR REGULATORY COMMISSION STANDARDS FOR PROTECTION AGAINST RADIATION Surveys and Monitoring § 20.1502 Conditions requiring individual monitoring of external and internal occupational dose. Each licensee shall monitor exposures to radiation and radioactive...
Code of Federal Regulations, 2012 CFR
2012-01-01
... internal occupational dose. 20.1502 Section 20.1502 Energy NUCLEAR REGULATORY COMMISSION STANDARDS FOR PROTECTION AGAINST RADIATION Surveys and Monitoring § 20.1502 Conditions requiring individual monitoring of external and internal occupational dose. Each licensee shall monitor exposures to radiation and radioactive...
Code of Federal Regulations, 2011 CFR
2011-01-01
... internal occupational dose. 20.1502 Section 20.1502 Energy NUCLEAR REGULATORY COMMISSION STANDARDS FOR PROTECTION AGAINST RADIATION Surveys and Monitoring § 20.1502 Conditions requiring individual monitoring of external and internal occupational dose. Each licensee shall monitor exposures to radiation and radioactive...
Code of Federal Regulations, 2013 CFR
2013-01-01
... internal occupational dose. 20.1502 Section 20.1502 Energy NUCLEAR REGULATORY COMMISSION STANDARDS FOR PROTECTION AGAINST RADIATION Surveys and Monitoring § 20.1502 Conditions requiring individual monitoring of external and internal occupational dose. Each licensee shall monitor exposures to radiation and radioactive...
Code of Federal Regulations, 2010 CFR
2010-01-01
... internal occupational dose. 20.1502 Section 20.1502 Energy NUCLEAR REGULATORY COMMISSION STANDARDS FOR PROTECTION AGAINST RADIATION Surveys and Monitoring § 20.1502 Conditions requiring individual monitoring of external and internal occupational dose. Each licensee shall monitor exposures to radiation and radioactive...
NASA Astrophysics Data System (ADS)
Burmeister, Soenke; Berger, Thomas; Reitz, Guenther; Boehme, Matthias; Haumann, Lutz; Labrenz, Johannes
Besides the effects of the microgravity environment, and the psychological and psychosocial problems encountered in confined spaces, radiation is the main health detriment for long duration human space missions. The radiation environment encountered in space differs in nature from that on earth, consisting mostly of high energetic ions from protons up to iron, resulting in radiation levels far exceeding the ones encountered on earth for occupational radiation workers. Accurate knowledge of the physical characteristics of the space radiation field in dependence on the solar activity, the orbital parameters and the different shielding configurations of the International Space Station ISS is therefore needed. For the investigation of the spatial and temporal distribution of the radiation field inside the European COLUMBUS module the experiment DOSIS (Dose Distribution Inside the ISS) under the lead of DLR has been launched on July 15 (th) 2009 with STS-127 to the ISS. The experimental package was transferred from the Space Shuttle into COLUMBUS on July 18 (th) . It consists of a combination of passive detector packages (PDP) distributed at 11 locations inside the European Columbus Laboratory and two active radiation detectors (Dosimetry Telescopes = DOSTELs) with a DDPU (DOSTEL Data and Power Unit) in a Nomex pouch (DOSIS MAIN BOX) mounted at a fixed location beneath the European Physiology Module rack (EPM) inside COLUMBUS. The active components of the DOSIS experiment were operational from July 18 (th) 2009 to June 16 (th) 2011. After refurbishment the hardware has been reactivated on May 15 (th) 2012 as active part of the DOSIS 3D experiment and provides continuous data since this activation. The presentation will focus on the latest results from the two DOSTEL instruments as absorbed dose, dose equivalent and the related LET spectra gathered within the DOSIS (2009 - 2011) and DOSIS 3D (2012 - 2014) experiment. The CAU contributions to DOSIS and DOSIS 3D are financially supported by BMWi under Grants 50WB0826, 50WB1026 and 50WB1232
TOWARDS A NOVEL MODULAR ARCHITECTURE FOR CERN RADIATION MONITORING.
Boukabache, Hamza; Pangallo, Michel; Ducos, Gael; Cardines, Nicola; Bellotta, Antonio; Toner, Ciarán; Perrin, Daniel; Forkel-Wirth, Doris
2017-04-01
The European Organization for Nuclear Research (CERN) has the legal obligation to protect the public and the people working on its premises from any unjustified exposure to ionising radiation. In this context, radiation monitoring is one of the main concerns of the Radiation Protection Group. After 30 y of reliable service, the ARea CONtroller (ARCON) system is approaching the end of its lifecycle, which raises the need for new, more efficient radiation monitors with a high level of modularity to ensure better maintainability. Based on these two main principles, new detectors are currently being developed that will be capable of measuring very low dose rates down to 50 nSv h-1, whilst being able to measure radiation over an extensive range of 8 decades without any auto scaling. To reach these performances, CERN Radiation MOnitoring Electronics (CROME), the new generation of CERN radiation monitors, is based on the versatile architecture that includes new read-out electronics developed by the Instrumentation and Logistics section of the CERN Radiation Protection Group as well as a reconfigurable system on chip capable of performing complex processing calculations. Beside the capabilities of CROME to continuously measure the ambient dose rate, the system generates radiation alarms, provides interlock signals, drives alarm display units through a fieldbus and provides long-term, permanent and reliable data logging. The measurement tests performed during the first phase of the development show very promising results that pave the way to the second phase: the certification. © The Author 2016. Published by Oxford University Press.
TOWARDS A NOVEL MODULAR ARCHITECTURE FOR CERN RADIATION MONITORING
Boukabache, Hamza; Pangallo, Michel; Ducos, Gael; Cardines, Nicola; Bellotta, Antonio; Toner, Ciarán; Perrin, Daniel; Forkel-Wirth, Doris
2017-01-01
Abstract The European Organization for Nuclear Research (CERN) has the legal obligation to protect the public and the people working on its premises from any unjustified exposure to ionising radiation. In this context, radiation monitoring is one of the main concerns of the Radiation Protection Group. After 30 y of reliable service, the ARea CONtroller (ARCON) system is approaching the end of its lifecycle, which raises the need for new, more efficient radiation monitors with a high level of modularity to ensure better maintainability. Based on these two main principles, new detectors are currently being developed that will be capable of measuring very low dose rates down to 50 nSv h−1, whilst being able to measure radiation over an extensive range of 8 decades without any auto scaling. To reach these performances, CERN Radiation MOnitoring Electronics (CROME), the new generation of CERN radiation monitors, is based on the versatile architecture that includes new read-out electronics developed by the Instrumentation and Logistics section of the CERN Radiation Protection Group as well as a reconfigurable system on chip capable of performing complex processing calculations. Beside the capabilities of CROME to continuously measure the ambient dose rate, the system generates radiation alarms, provides interlock signals, drives alarm display units through a fieldbus and provides long-term, permanent and reliable data logging. The measurement tests performed during the first phase of the development show very promising results that pave the way to the second phase: the certification. PMID:27909154
Fiorina, E; Ferrero, V; Pennazio, F; Baroni, G; Battistoni, G; Belcari, N; Cerello, P; Camarlinghi, N; Ciocca, M; Del Guerra, A; Donetti, M; Ferrari, A; Giordanengo, S; Giraudo, G; Mairani, A; Morrocchi, M; Peroni, C; Rivetti, A; Da Rocha Rolo, M D; Rossi, S; Rosso, V; Sala, P; Sportelli, G; Tampellini, S; Valvo, F; Wheadon, R; Bisogni, M G
2018-05-07
Hadrontherapy is a method for treating cancer with very targeted dose distributions and enhanced radiobiological effects. To fully exploit these advantages, in vivo range monitoring systems are required. These devices measure, preferably during the treatment, the secondary radiation generated by the beam-tissue interactions. However, since correlation of the secondary radiation distribution with the dose is not straightforward, Monte Carlo (MC) simulations are very important for treatment quality assessment. The INSIDE project constructed an in-beam PET scanner to detect signals generated by the positron-emitting isotopes resulting from projectile-target fragmentation. In addition, a FLUKA-based simulation tool was developed to predict the corresponding reference PET images using a detailed scanner model. The INSIDE in-beam PET was used to monitor two consecutive proton treatment sessions on a patient at the Italian Center for Oncological Hadrontherapy (CNAO). The reconstructed PET images were updated every 10 s providing a near real-time quality assessment. By half-way through the treatment, the statistics of the measured PET images were already significant enough to be compared with the simulations with average differences in the activity range less than 2.5 mm along the beam direction. Without taking into account any preferential direction, differences within 1 mm were found. In this paper, the INSIDE MC simulation tool is described and the results of the first in vivo agreement evaluation are reported. These results have justified a clinical trial, in which the MC simulation tool will be used on a daily basis to study the compliance tolerances between the measured and simulated PET images. Copyright © 2018 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.
NASA Astrophysics Data System (ADS)
Vinoj, V.; Fast, J. D.; Liu, Y.
2012-12-01
Aerosols have been identified to be a major contributor to the uncertainty in understanding the present climate. Most of this uncertainty arises due to the lack of knowledge of their micro-physical and chemical properties as well as how to adequately represent their spatial and temporal distributions. Increased process level understanding can be achieved through carefully designed field campaigns and experiments. These measurements can be used to elucidate the aerosol properties, mixing, transport and transformation within the atmosphere and also to validate and improve models that include meteorology-aerosol-chemistry interactions. In the present study, the WRF-Chem model is used to simulate the evolution of carbonaceous and inorganic aerosols and their impact on radiation during May and June of 2010 over California when two field campaigns took place: the California Nexus Experiment (CalNex) and Carbonaceous Aerosol and Radiative Effects Study (CARES). We merged CalNex and CARES data along with data from operational networks such as, California Air Resources Board (CARB's) air quality monitoring network, the Interagency Monitoring of Protected Visual Environments (IMPROVE) network, the AErosol RObotic NETwork (AERONET), and satellites into a common dataset for the Aerosol Modeling Test bed. The resulting combined dataset is used to rigorously evaluate the model simulation of aerosol mass, size distribution, composition, and optical properties needed to understand uncertainties that could affect regional variations in aerosol radiative forcing. The model reproduced many of the diurnal, multi-day, and spatial variations of aerosols as seen in the measurements. However, regionally the performance varied with reasonably good agreement with observations around Los Angeles and Sacramento and poor agreement with observations in the vicinity of Bakersfield (although predictions aloft were much better). Some aerosol species (sulfate and nitrate) were better represented than others (organic matter, black carbon) at many locations. The model also reproduced the observed transport of sea-salt by intrusions of marine air from the Bay Area to Sacramento. The vertical distribution of aerosols was simulated reasonably as evidenced from comparison with observed profiles from the High Spectral Resolution Lidar (HSRL) on the NASA B-200 aircraft, although the values in the boundary layer were too high at times. Consistent with the bias in aerosol mass, the simulated column aerosol optical depths at the AERONET and field campaign sites were often too high. Comparisons between observed and predicted aerosol optical depth and single scattering albedo will be presented. Using aerosol observations as a constraint, we will present the radiative effect of simulated aerosols and its sensitivity to the uncertainties in predicted aerosol properties.
NRC TLD Direct Radiation Monitoring Network. Progress report, October--December 1996
DOE Office of Scientific and Technical Information (OSTI.GOV)
Struckmeyer, R.
This report presents the results of the NRC Direct Radiation Monitoring Network for the fourth quarter of 1996. It provides the ambient radiation levels measured in the vicinity of 74 sites throughout the United States. In addition, it describes the equipment used, monitoring station selection criteria, characterization of the dosimeter response, calibration procedures, statistical methods, intercomparison, and quality assurance program. 3 figs., 4 tabs.
NASA Astrophysics Data System (ADS)
Gaidash, A. A.; Egorov, V. I.; Gleim, A. V.
2016-08-01
Quantum cryptography allows distributing secure keys between two users so that any performed eavesdropping attempt would be immediately discovered. However, in practice an eavesdropper can obtain key information from multi-photon states when attenuated laser radiation is used as a source of quantum states. In order to prevent actions of an eavesdropper, it is generally suggested to implement special cryptographic protocols, like decoy states or SARG04. In this paper, we describe an alternative method based on monitoring photon number statistics after detection. We provide a useful rule of thumb to estimate approximate order of difference of expected distribution and distribution in case of attack. Formula for calculating a minimum value of total pulses or time-gaps to resolve attack is shown. Also formulas for actual fraction of raw key known to Eve were derived. This method can therefore be used with any system and even combining with mentioned special protocols.
NASA Astrophysics Data System (ADS)
Nehrir, A. R.; Hoffman, D. S.; Repasky, K. S.; Todt, B.; Sharpe, T.; Half Red, C.; Carlsten, J. L.
2009-12-01
Coupled atmospheric components of the lower troposphere including aerosols and water vapor have a large affect on the chemical processes that drive the earth’s complex climate system. Aerosols can affect the earth’s global radiation budget directly by absorbing or reflecting incoming solar radiation, and indirectly by changing the microphysical properties of clouds by serving as cloud condensation nuclei (CCN). An increase in CCN results in higher cloud droplet concentration which has been shown to suppress drizzle formation and lead to more reflective clouds. The changes in the cloud microphysical structure due to the interaction of aerosols and water vapor result in more incoming solar radiation being reflected back into space, leading to a net negative radiative forcing in the global radiation budget. The uncertainty in this radiative forcing reflects the uncertainty in the understanding of the aerosol indirect effect and its role in the climate system. To better understand the aerosol direct and indirect effects, lidar measurements of aerosol properties and water vapor distributions can provide important information to enhance our understanding of the role of aerosols in the climate system. The LIDAR group at Montana State University has initiated a program to simultaneously study aerosols, water vapor, and cloud formation with high spatial and temporal resolution using both active and passive sensors. Aerosol distributions and radiative properties are currently being studied with a two-color LIDAR system at 1064 and 532 nm. In addition, a three color, high spectral resolution LIDAR system at 1064,532, and 355 nm has also been developed and is starting to take initial data. Daytime and nighttime boundary layer water vapor number density profiles are also currently being studied with an external cavity diode oscillator/diode amplifier based micro-pulsed differential absorption lidar (DIAL) instrument at the 830 nm water vapor absorption band. Cloud formation studies are being conducted by a simultaneous, spatially correlated digital sky imaging camera system where aerosol loading and water vapor distributions are monitored as a function of lateral distance to clouds. Furthermore, a commercially purchased sun/sky scanning solar radiometer (CIMEL 318) as part of the NASA run AERONET program is also being used to study aerosol loading and radiative transfer through the atmosphere. A brief description of these instruments will be presented as well as initial simultaneous results showing correlated data between lower tropospheric aerosols and boundary layer water vapor distributions over extended periods if time.
On the watch for geomagnetic storms
Green, Arthur W.; Brown, William M.
1997-01-01
Geomagnetic storms, induced by solar activity, pose significant hazards to satellites, electrical power distribution systems, radio communications, navigation, and geophysical surveys. Strong storms can expose astronauts and crews of high-flying aircraft to dangerous levels of radiation. Economic losses from recent geomagnetic storms have run into hundreds of millions of dollars. With the U.S. Geological Survey (USGS) as the lead agency, an international network of geomagnetic observatories monitors the onset of solar-induced storms and gives warnings that help diminish losses to military and commercial operations and facilities.
1990-12-01
Zerodur ,irror, 2" relfects light. 1OZ20BD.1; 20th wave zerodur mirror , 1" reflects light. LS-35; 3’ x 5’ optical breadboard; for mounting components...profile measurements using the diffuse screen were compared with measurements using a front surface mirror and a fluorescent screen. The 20 DISTRIBUTION...Beam current and profile measurements using the diffuse screen were compared with measurements using a front surface mirror and a fluorescent screen
Doke, T; Hayashi, T; Hasebe, N; Kikuchi, J; Kono, S; Murakami, T; Sakaguchi, T; Takahashi, K; Takashima, T
1996-12-01
A new telescope consisting of three two-dimensional position-sensitive silicon detectors which can measure the linear energy transfer (LET) distribution over the range from 0.2 to 400keV/micrometers has been developed as a real-time radiation monitor in manned spacecraft. First, the principle of LET measurement and its design method are described. Second, suitable electronic parameters for the LET measurement are experimentally determined. Finally the telescope performance is investigated by using, relativistic heavy ions. The first in-flight test of this type of telescope on the US Space Shuttle (STS-84) is scheduled for May, 1997.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Farfan, E.; Jannik, T.
2011-10-01
This article describes results of the radiation environmental monitoring performed in the Chernobyl Exclusion Zone (ChEZ) during the period following the 1986 Chernobyl Nuclear Power Plant accident. This article presents a brief overview of five comprehensive reports generated under Contract No. DE-AC09-96SR18500 (Washington Savannah River Company LLC, Subcontract No. AC55559N, SOW No. ON8778) and summarizes characteristics of the ChEZ and its post-accident status and the history of development of the radiation monitoring research in the ChEZ is described. This article addresses characteristics of the radiation monitoring in the ChEZ, its major goals and objectives, and changes of these goals andmore » objectives in the course of time, depending on the tasks associated with the phase of mitigation of the ChNPP accident consequences. The results of the radiation monitoring in the ChEZ during the last 25 years are also provided.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Struckmeyer, R.
This report presents the results of the NRC Direct Radiation Monitoring Network for the fourth quarter of 1995. It provides the ambient radiation levels measured in the vicinity of 75 sites throughout the United States. In addition, it describes the equipment used, monitoring station selection criteria, characterization of the dosimeter response, calibration procedures, statistical methods, intercomparison, and quality assurance program.
Application accelerator system having bunch control
Wang, Dunxiong; Krafft, Geoffrey Arthur
1999-01-01
An application accelerator system for monitoring the gain of a free electron laser. Coherent Synchrotron Radiation (CSR) detection techniques are used with a bunch length monitor for ultra short, picosec to several tens of femtosec, electron bunches. The monitor employs an application accelerator, a coherent radiation production device, an optical or beam chopping device, an infrared radiation collection device, a narrow-banding filter, an infrared detection device, and a control.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Liu, B.
2016-06-15
Radiation dose monitoring solutions have opened up new opportunities for medical physicists to be more involved in modern clinical radiology practices. In particular, with the help of comprehensive radiation dose data, data-driven protocol management and informed case follow up are now feasible. Significant challenges remain however and the problems faced by medical physicists are highly heterogeneous. Imaging systems from multiple vendors and a wide range of vintages co-exist in the same department and employ data communication protocols that are not fully standardized or implemented making harmonization complex. Many different solutions for radiation dose monitoring have been implemented by imaging facilitiesmore » over the past few years. Such systems are based on commercial software, home-grown IT solutions, manual PACS data dumping, etc., and diverse pathways can be used to bring the data to impact clinical practice. The speakers will share their experiences with creating or tailoring radiation dose monitoring/management systems and procedures over the past few years, which vary significantly in design and scope. Topics to cover: (1) fluoroscopic dose monitoring and high radiation event handling from a large academic hospital; (2) dose monitoring and protocol optimization in pediatric radiology; and (3) development of a home-grown IT solution and dose data analysis framework. Learning Objectives: Describe the scope and range of radiation dose monitoring and protocol management in a modern radiology practice Review examples of data available from a variety of systems and how it managed and conveyed. Reflect on the role of the physicist in radiation dose awareness.« less
TH-E-209-02: Dose Monitoring and Protocol Optimization: The Pediatric Perspective
DOE Office of Scientific and Technical Information (OSTI.GOV)
MacDougall, R.
Radiation dose monitoring solutions have opened up new opportunities for medical physicists to be more involved in modern clinical radiology practices. In particular, with the help of comprehensive radiation dose data, data-driven protocol management and informed case follow up are now feasible. Significant challenges remain however and the problems faced by medical physicists are highly heterogeneous. Imaging systems from multiple vendors and a wide range of vintages co-exist in the same department and employ data communication protocols that are not fully standardized or implemented making harmonization complex. Many different solutions for radiation dose monitoring have been implemented by imaging facilitiesmore » over the past few years. Such systems are based on commercial software, home-grown IT solutions, manual PACS data dumping, etc., and diverse pathways can be used to bring the data to impact clinical practice. The speakers will share their experiences with creating or tailoring radiation dose monitoring/management systems and procedures over the past few years, which vary significantly in design and scope. Topics to cover: (1) fluoroscopic dose monitoring and high radiation event handling from a large academic hospital; (2) dose monitoring and protocol optimization in pediatric radiology; and (3) development of a home-grown IT solution and dose data analysis framework. Learning Objectives: Describe the scope and range of radiation dose monitoring and protocol management in a modern radiology practice Review examples of data available from a variety of systems and how it managed and conveyed. Reflect on the role of the physicist in radiation dose awareness.« less
Dilworth, R.H.; Borkowski, C.J.
1961-12-26
A transistorized, fountain pen type radiation monitor to be worn on the person is described. Radiation produces both light flashes in a small bulb and an audible warning tone, the frequency of both the tone and light flashes being proportional to radiation intensity. The device is powered by a battery and a blocking oscillator step-up power supply The oscillator frequency- is regulated to be proportional to the radiation intensity, to provide adequate power in high radiation fields, yet minimize battery drain at low operating intensities. (AEC)
Magnetic Resonance Imaging of Adipose Tissue in Metabolic Dysfunction.
Franz, Daniela; Syväri, Jan; Weidlich, Dominik; Baum, Thomas; Rummeny, Ernst J; Karampinos, Dimitrios C
2018-06-06
Adipose tissue has become an increasingly important tissue target in medicine. It plays a central role in the storage and release of energy throughout the human body and has recently gained interest for its endocrinologic function. Magnetic resonance imaging (MRI) is an established method for quantitative direct evaluation of adipose tissue distribution, and is used increasingly as the modality of choice for metabolic phenotyping. The purpose of this review was the identification and presentation of the currently available literature on MRI of adipose tissue in metabolic dysfunction. A PubMed (http://www.ncbi.nlm.nih.gov/pubmed) keyword search up to August 2017 without starting date limitation was performed and reference lists of relevant articles were searched. MRI provides excellent tools for the evaluation of adipose tissue distribution and further characterization of the tissue. Standard as well as newly developed MRI techniques allow a risk stratification for the development of metabolic dysfunction and enable monitoring without the use of ionizing radiation or contrast material. · Different types of adipose tissue play a crucial role in various types of metabolic dysfunction.. · Magnetic resonance imaging (MRI) is an excellent tool for noninvasive adipose tissue evaluation with respect to distribution, composition and metabolic activity.. · Both standard and newly developed MRI techniques can be used for risk stratification for the development of metabolic dysfunction and allow monitoring without the use of ionizing radiation or contrast material.. · Franz D, Syväri J, Weidlich D et al. Magnetic Resonance Imaging of Adipose Tissue in Metabolic Dysfunction. Fortschr Röntgenstr 2018; DOI: 10.1055/a-0612-8006. © Georg Thieme Verlag KG Stuttgart · New York.
Quigley, Martin M; Mate, Timothy P; Sylvester, John E
2009-01-01
To evaluate the accuracy, utility, and cost effectiveness of a new electromagnetic patient positioning and continuous, real-time monitoring system, which uses permanently implanted resonant transponders in the target (Calypso 4D Localization System and Beacon transponders, Seattle, WA) to continuously monitor tumor location and movement during external beam radiation therapy of the prostate. This clinical trial studied 43 patients at 5 sites. All patients were implanted with 3 transponders each. In 41 patients, the system was used for initial alignment at each therapy session. Thirty-five patients had continuous monitoring during their radiation treatment. Over 1,000 alignment comparisons were made to a commercially available kV X-ray positioning system (BrainLAB ExacTrac, Munich, Germany). Using decision analysis and Markov processes, the outcomes of patients were simulated over a 5-year period and measured in terms of costs from a payer's perspective and quality-adjusted life years (QALYs). All patients had satisfactory transponder implantations for monitoring purposes. In over 75% of the treatment sessions, the correction to conventional positioning (laser and tattoos) directed by an electromagnetic patient positioning and monitoring system was greater than 5 mm. Ninety-seven percent (34/35) of the patients who underwent continuous monitoring had target motion that exceeded preset limits at some point during the course of their radiation therapy. Exceeding preset thresholds resulted in user intervention at least once during the therapy in 80% of the patients (28/35). Compared with localization using ultrasound, electronic portal imaging devices (EPID), or computed tomography (CT), localization with the electromagnetic patient positioning and monitoring system yielded superior gains in QALYs at comparable costs. Most patients positioned with conventional tattoos and lasers for prostate radiation therapy were found by use of the electromagnetic patient positioning and monitoring system to have alignment errors exceeding 5 mm. Almost all patients undergoing external beam radiation of the prostate have been shown to have target organ movement exceeding 3 mm during radiation therapy delivery. The ability of the electromagnetic technology to monitor tumor target location during the same time as radiation therapy is being delivered allows clinicians to provide real time adaptive radiation therapy for prostate cancer. This permits clinicians to intervene when the prostate moves outside the radiation isocenter, which should decrease adverse events and improve patient outcomes. Additionally, a cost-utility analysis has demonstrated that the electromagnetic patient positioning and monitoring system offers patient outcome benefits at a cost that falls well within the payer's customary willingness to pay (WTP) threshold of $50,000 per QALY.
Liu, Chuanlei; Zhang, Weihua; Ungar, Kurt; Korpach, Ed; White, Brian; Benotto, Mike; Pellerin, Eric
2018-05-07
This work explores the application of Health Canada's Fixed Point Surveillance (FPS) network for cosmic ray monitoring and dose estimation purposes. This network is comprised of RS250 3 inch by 3 inch Sodium Iodide (NaI) spectroscopic dosimeters distributed throughout Canada. The RS250's high channel count rate responds to the electromagnetic and muonic components of cosmic ray shower. These count rates are used to infer cosmic ray doses throughout FPS locations. The derived dose was found to have an accuracy within 6.5% deviation relative to theoretical calculation. The solar cycle effect and meteorologically induced fluctuation can be realistically reflected in the estimated dose. This work may serve as a basis to enable the FPS network to monitor and report both terrestrial and cosmic radiation in quasi-real time. Crown Copyright © 2018. Published by Elsevier Ltd. All rights reserved.
NASA Astrophysics Data System (ADS)
Wu, Juan; Melo, Lis G. A.; Zhu, Xiaohui; West, Marcia M.; Berejnov, Viatcheslav; Susac, Darija; Stumper, Juergen; Hitchcock, Adam P.
2018-03-01
4D imaging - the three-dimensional distributions of chemical species determined using multi-energy X-ray tomography - of cathode catalyst layers of polymer electrolyte membrane fuel cells (PEM-FC) has been measured by scanning transmission x-ray microscopy (STXM) spectro-tomography at the C 1s and F 1s edges. In order to monitor the effects of radiation damage on the composition and 3D structure of the perfluorosulfonic acid (PFSA) ionomer, the same volume was measured 3 times sequentially, with spectral characterization of that same volume at several time points during the measurements. The changes in the average F 1s spectrum of the ionomer in the cathode as the measurements progressed gave insights into the degree of chemical modification, fluorine mass loss, and changes in the 3D distributions of ionomer that accompanied the spectro-tomographic measurement. The PFSA ionomer-in-cathode is modified both chemically and physically by radiation damage. The 3D volume decreases anisotropically. By reducing the incident flux, partial defocusing (50 nm spot size), limiting the number of tilt angles to 14, and using compressed sensing reconstruction, we show it is possible to reproducibly measure the 3D structure of ionomer in PEM-FC cathodes at ambient temperature while causing minimal radiation damage.
NASA Astrophysics Data System (ADS)
Cherviakov, Maksim; Bogdanov, Mikhail; Spiryakhina, Anastasia; Shishkina, Elena; Surkova, Yana; Kulkova, Eugenia
2017-04-01
This report describes Earth's radiation budget IKOR-M satellite program which has been started in Russia. The first satellite "Meteor-M» No 1 of this project was put into orbit in September, 2009. The IKOR-M radiometer is a satellite instrument that measures reflected shortwave radiation (0.3-4.0 µm). It was created in Saratov State University and installed on Russian hydrometeorological satellites "Meteor-M" No 1 and No 2. Radiometer IKOR-M designed for satellite monitoring of the outgoing reflected short-wave radiation, which is one of the components of Earth's radiation budget. Such measurements can be used to derive Earth's surface albedo and absorbed solar radiation. This information also can be used in different models of long-term weather forecasts and in researches of climate change trends (Sklyarov et al., 2016). Satellite "Meteor-M" No 1 and No 2 are heliosynchronous that allows observing from North to South Poles. The basic products of data processing are given in the form of global maps of distribution outgoing short-wave radiation (OSR), albedo and absorbed solar radiation (ASR). Such maps were made for each month during observation period. The IKOR-M product archive is available online at all times. A searchable catalogue of data products is continually updated and users may search and download data products via the Earth radiation balance components research laboratory website (http://www.sgu.ru/structure/geographic/metclim/balans) as soon as they become available. Two series of measurements from two different IKOR-M are available. The first radiometer had worked from October, 2009 to August, 2014 and second - from August, 2014 to the present. Therefore, there is a period when both radiometers work at the same time. Top-of-atmosphere fluxes deduced from the "Meteor-M" No 1 measurements in August, 2014 show very good agreement with the fluxes determined from "Meteor-M" No 2 (Bogdanov et al., 2016). The effect of aging is investigated for first IKOR-M. This radiometer worked on board of the "Meteor-M" No 1 satellite for five years. Parameters of linear trends are estimated for the Earth's surface area albedo with approximately constant values of this characteristic and the estimate of sensitivity change over time for the radiometer is obtained. The seasonal and interannual variations of OSR, albedo and ASR were discussed. The variations between SW radiation budget components seem to be within observational uncertainty and natural variability governed by cloudiness, water vapor and aerosol variations. It should be noted that cloudiness makes a significant contribution to the planetary albedo of the Earth, largely determines its spatial-temporal distribution. In particular, it is important to know what contribution cloudiness makes to albedo and what the relationship between them. Therefore, comparisons between albedo and cloudiness were conducted separately for land and oceans. The comparison of the distributions of cloudiness and albedo had identified the existence of significant correlation to the World Ocean, lower values for the World Ocean and land together and small correlation for land. It was assessed spatial and temporal variations of albedo and the absorbed solar radiation over different regions. Latitudinal distributions of albedo and ASR were estimated in more detail. Meridional cross sections over oceans and land were used separately for this estimation. It was shown that the albedo and ASR data received from the radiometer IKOR-M can be used to detect El Nino in the Pacific Ocean and monitoring of the East Asian Summer Monsoon. The report will be presented more detailed results. The reported study was funded by Russian Geographical Society according financial support in the framework of a research project No 40/2016-R. Latitudinal distributions of albedo and ASR study was funded by RFBR according to the research project No.16-35-00284 mol_a. References 1. Sklyarov Yu.A., Vorob'ev V.A., Kotuma A.I., Chervyakov M.Yu., Feigin V.M. The measurement of the radiation balance component from "Meteor-M" satellite. The IKOR-M radiometer // Sovremennye problemy distantsionnogo zondirovaniya Zemli iz kosmosa, 2012, Vol. 9, No 2, pp. 173-180. 2. Sklyarov Yu.A., Vorob'ev V.A., Kotuma A.I., Chervyakov M.Yu., Feigin V.M. The algorithms for the processing of outgoing shortwave radiation measurements from "Meteor- M" No 1 satellite // Sovremennye problemy distantsionnogo zondirovaniya Zemli iz kosmosa, 2012, Vol. 9, No 3, pp. 83-90. 3. Bogdanov M.B., Vorobyov A.I., Kotuma A.I., Cherviakov M.Yu. Scaling factor between reflected shortwave radiation mesured by IKOR-M on board the Veteor-M No 1 and No 2 // Sovremennye problemy distantsionnogo zondirovaniya Zemli iz kosmosa, 20126, Vol. 13, No4, pp. 252-260.
Application accelerator system having bunch control
Wang, D.; Krafft, G.A.
1999-06-22
An application accelerator system for monitoring the gain of a free electron laser is disclosed. Coherent Synchrotron Radiation (CSR) detection techniques are used with a bunch length monitor for ultra short, picosec to several tens of femtosec, electron bunches. The monitor employs an application accelerator, a coherent radiation production device, an optical or beam chopping device, an infrared radiation collection device, a narrow-banding filter, an infrared detection device, and a control. 1 fig.
Theis, C; Forkel-Wirth, D; Perrin, D; Roesler, S; Vincke, H
2005-01-01
Monitoring of the radiation environment is one of the key tasks in operating a high-energy accelerator such as the Large Hadron Collider (LHC). The radiation fields consist of neutrons, charged hadrons as well as photons and electrons with energy spectra extending from those of thermal neutrons up to several hundreds of GeV. The requirements for measuring the dose equivalent in such a field are different from standard uses and it is thus necessary to investigate the response of monitoring devices thoroughly before the implementation of a monitoring system can be conducted. For the LHC, it is currently foreseen to install argon- and hydrogen-filled high-pressure ionisation chambers as radiation monitors of mixed fields. So far their response to these fields was poorly understood and, therefore, further investigation was necessary to prove that they can serve their function well enough. In this study, ionisation chambers of type IG5 (Centronic Ltd) were characterised by simulating their response functions by means of detailed FLUKA calculations as well as by calibration measurements for photons and neutrons at fixed energies. The latter results were used to obtain a better understanding and validation of the FLUKA simulations. Tests were also conducted at the CERF facility at CERN in order to compare the results with simulations of the response in a mixed radiation field. It is demonstrated that these detectors can be characterised sufficiently enough to serve their function as radiation monitors for the LHC.
The design of Radiation Accident Registry.
Chen, Jing; Seely, Bob; Bergman, Lauren; Moir, Deborah
2011-03-01
In order to provide effective monitoring and follow-up on the health effects of individuals accidentally exposed to ionising radiation, a Radiation Accident Registry (RAR) has been designed and constructed as an extension to the existing National Dose Registry (NDR). The RAR has basic functions of recording, monitoring and reporting. This type of registry is able to assist responders in preparing for and managing situations during radiological events and in providing effective follow-up on the long-term health effects of persons exposed to ionising radiation. It is especially important to register radiation-exposed people in vulnerable population groups, such as children and pregnant women, to ensure proper long-term health care and protection. Even though radiation accidents are rare, a registry prepared for such accidents could involve a large population and, in some cases, require lifetime monitoring for individuals. One of the most challenging tasks associated with RAR is the assessment of radiation dose resulting from accidents. In some cases, the assessment of radiation doses to individuals could be a process requiring the involvement of various methods. The development of fast and accurate dose assessment tools will remain a long-term challenge associated with the RAR. To meet this challenge, further research activities in radiation dosimetry for individual monitoring are needed.
Henzen, Dominik; Schmidhalter, Daniel; Zanella, Claudia Christina; Volken, Werner; Mackeprang, Paul-Henry; Malthaner, Marco; Fix, Michael Karl; Manser, Peter
2018-01-01
Compared to a conventional linear accelerator, the Cyberknife (CK) is a unique system with respect to radiation protection shielding and the variety and number of non-coplanar beams are two key components regarding this aspect. In this work, a framework to assess the direction distribution and modulation factor (MF) of clinically applied treatment beams of a CyberKnife M6 is developed. Database filtering options allow studying the influence of different parameters such as collimator types, treatment sites or different bunker sizes. A distribution of monitor units (MU) is generated by projecting treatment beams onto the walls, floor and ceiling of the CyberKnife bunker. This distribution is found to be highly heterogeneous and depending, among other parameters, on the bunker size. For our bunker design, 10%-13% of the MUs are delivered to the right and left wall, each. The floor receives more than 64% of the applied MUs, while the wall behind the patient's head is not hit by primary treatment beams. Between 0% and 5% of the total MUs are delivered to the wall at the patient's feet. This number highly depends on the treatment site, e.g., for extracranial patients no beams hit that wall. Collimator choice was found to have minor influence on the distribution of MUs. On the other hand, the MF depends on the collimator type as well as on the treatment site. The MFs (delivered MU/prescribed dose) for all treatments, all MLC treatments, cranial and extracranial treatments are 8.3, 6.4, 7.7, and 9.9 MU/cGy, respectively. The developed framework allows assessing and monitoring important parameters regarding radiation protection of a CK-M6 using the actually applied treatment beams. Furthermore, it enables evaluating different clinical and constructional situations using the filtering options. © 2017 The Authors. Journal of Applied Clinical Medical Physics published by Wiley Periodicals, Inc. on behalf of American Association of Physicists in Medicine.
Gamma-ray spectra and doses from the Little Boy replica
DOE Office of Scientific and Technical Information (OSTI.GOV)
Moss, C.E.; Lucas, M.C.; Tisinger, E.W.
1984-01-01
Most radiation safety guidelines in the nuclear industry are based on the data concerning the survivors of the nuclear explosions at Hiroshima and Nagasaki. Crucial to determining these guidelines is the radiation from the explosions. We have measured gamma-ray pulse-height distributions from an accurate replica of the Little Boy device used at Hiroshima, operated at low power levels near critical. The device was placed outdoors on a stand 4 m from the ground to minimize environmental effects. The power levels were based on a monitor detector calibrated very carefully in independent experiments. High-resolution pulse-height distributions were acquired with a germaniummore » detector to identify the lines and to obtain line intensities. The 7631 to 7645 keV doublet from neutron capture in the heavy steel case was dominant. Low-resolution pulse-height distributions were acquired with bismuth-germanate detectors. We calculated flux spectra from these distributions using accurately measured detector response functions and efficiency curves. We then calculated dose-rate spectra from the flux spectra using a flux-to-dose-rate conversion procedure. The integral of each dose-rate spectrum gave an integral dose rate. The integral doses at 2 m ranged from 0.46 to 1.03 mrem per 10/sup 13/ fissions. The output of the Little Boy replica can be calculated with Monte Carlo codes. Comparison of our experimental spectra, line intensities, and integral doses can be used to verify these calculations at low power levels and give increased confidence to the calculated values from the explosion at Hiroshima. These calculations then can be used to establish better radiation safety guidelines. 7 references, 7 figures, 2 tables.« less
10 CFR 34.47 - Personnel monitoring.
Code of Federal Regulations, 2010 CFR
2010-01-01
... 10 Energy 1 2010-01-01 2010-01-01 false Personnel monitoring. 34.47 Section 34.47 Energy NUCLEAR REGULATORY COMMISSION LICENSES FOR INDUSTRIAL RADIOGRAPHY AND RADIATION SAFETY REQUIREMENTS FOR INDUSTRIAL RADIOGRAPHIC OPERATIONS Radiation Safety Requirements § 34.47 Personnel monitoring. (a) The licensee may not...
10 CFR 34.47 - Personnel monitoring.
Code of Federal Regulations, 2011 CFR
2011-01-01
... 10 Energy 1 2011-01-01 2011-01-01 false Personnel monitoring. 34.47 Section 34.47 Energy NUCLEAR REGULATORY COMMISSION LICENSES FOR INDUSTRIAL RADIOGRAPHY AND RADIATION SAFETY REQUIREMENTS FOR INDUSTRIAL RADIOGRAPHIC OPERATIONS Radiation Safety Requirements § 34.47 Personnel monitoring. (a) The licensee may not...
10 CFR 34.47 - Personnel monitoring.
Code of Federal Regulations, 2014 CFR
2014-01-01
... 10 Energy 1 2014-01-01 2014-01-01 false Personnel monitoring. 34.47 Section 34.47 Energy NUCLEAR REGULATORY COMMISSION LICENSES FOR INDUSTRIAL RADIOGRAPHY AND RADIATION SAFETY REQUIREMENTS FOR INDUSTRIAL RADIOGRAPHIC OPERATIONS Radiation Safety Requirements § 34.47 Personnel monitoring. (a) The licensee may not...
10 CFR 34.47 - Personnel monitoring.
Code of Federal Regulations, 2012 CFR
2012-01-01
... 10 Energy 1 2012-01-01 2012-01-01 false Personnel monitoring. 34.47 Section 34.47 Energy NUCLEAR REGULATORY COMMISSION LICENSES FOR INDUSTRIAL RADIOGRAPHY AND RADIATION SAFETY REQUIREMENTS FOR INDUSTRIAL RADIOGRAPHIC OPERATIONS Radiation Safety Requirements § 34.47 Personnel monitoring. (a) The licensee may not...
10 CFR 34.47 - Personnel monitoring.
Code of Federal Regulations, 2013 CFR
2013-01-01
... 10 Energy 1 2013-01-01 2013-01-01 false Personnel monitoring. 34.47 Section 34.47 Energy NUCLEAR REGULATORY COMMISSION LICENSES FOR INDUSTRIAL RADIOGRAPHY AND RADIATION SAFETY REQUIREMENTS FOR INDUSTRIAL RADIOGRAPHIC OPERATIONS Radiation Safety Requirements § 34.47 Personnel monitoring. (a) The licensee may not...
Code of Federal Regulations, 2012 CFR
2012-07-01
... humidity, solar radiation, ultraviolet radiation, and/or precipitation. Metropolitan Statistical Area (MSA... receiver at opposite ends of the monitoring path; (2) Equal to twice the monitoring path length for a (monostatic) system having a transmitter and receiver at one end of the monitoring path and a mirror or...
Code of Federal Regulations, 2013 CFR
2013-07-01
... humidity, solar radiation, ultraviolet radiation, and/or precipitation. Metropolitan Statistical Area (MSA... receiver at opposite ends of the monitoring path; (2) Equal to twice the monitoring path length for a (monostatic) system having a transmitter and receiver at one end of the monitoring path and a mirror or...
Code of Federal Regulations, 2014 CFR
2014-07-01
... humidity, solar radiation, ultraviolet radiation, and/or precipitation. Metropolitan Statistical Area (MSA... receiver at opposite ends of the monitoring path; (2) Equal to twice the monitoring path length for a (monostatic) system having a transmitter and receiver at one end of the monitoring path and a mirror or...
Search for nonthermal effects of 434 MHz microwave radiation on whole human blood
DOE Office of Scientific and Technical Information (OSTI.GOV)
Dunscombe, P.B.; Gammampila, K.; Ramsey, N.W.
1983-11-01
Whole human blood was subjected to a microwave environment at 434 MHz for 6 h with external electric fields corresponding to free space power densities up to 598 mW cm/sup -2/ and the levels of hemoglobin, sodium, and potassium in the plasma were monitored. Under geometrical conditions in which the field strength within the samples was unknown, measurements indicated increased red cell membrane fragility following irradiation. It was possible to exclude localized heating as an explanation of this effect. However, with a known and reasonably uniform electric field distribution within spherical specimens, increased membrane fragility was not observed. We aremore » therefore unable to confirm previously reported results which indicate a nonthermal deleterious effect of microwave radiation on erythrocytes.« less
Evaluation of coded aperture radiation detectors using a Bayesian approach
NASA Astrophysics Data System (ADS)
Miller, Kyle; Huggins, Peter; Labov, Simon; Nelson, Karl; Dubrawski, Artur
2016-12-01
We investigate tradeoffs arising from the use of coded aperture gamma-ray spectrometry to detect and localize sources of harmful radiation in the presence of noisy background. Using an example application scenario of area monitoring and search, we empirically evaluate weakly supervised spectral, spatial, and hybrid spatio-spectral algorithms for scoring individual observations, and two alternative methods of fusing evidence obtained from multiple observations. Results of our experiments confirm the intuition that directional information provided by spectrometers masked with coded aperture enables gains in source localization accuracy, but at the expense of reduced probability of detection. Losses in detection performance can however be to a substantial extent reclaimed by using our new spatial and spatio-spectral scoring methods which rely on realistic assumptions regarding masking and its impact on measured photon distributions.
Susong, D.; Marks, D.; Garen, D.
1999-01-01
Topographically distributed energy- and water-balance models can accurately simulate both the development and melting of a seasonal snowcover in the mountain basins. To do this they require time-series climate surfaces of air temperature, humidity, wind speed, precipitation, and solar and thermal radiation. If data are available, these parameters can be adequately estimated at time steps of one to three hours. Unfortunately, climate monitoring in mountain basins is very limited, and the full range of elevations and exposures that affect climate conditions, snow deposition, and melt is seldom sampled. Detailed time-series climate surfaces have been successfully developed using limited data and relatively simple methods. We present a synopsis of the tools and methods used to combine limited data with simple corrections for the topographic controls to generate high temporal resolution time-series images of these climate parameters. Methods used include simulations, elevational gradients, and detrended kriging. The generated climate surfaces are evaluated at points and spatially to determine if they are reasonable approximations of actual conditions. Recommendations are made for the addition of critical parameters and measurement sites into routine monitoring systems in mountain basins.Topographically distributed energy- and water-balance models can accurately simulate both the development and melting of a seasonal snowcover in the mountain basins. To do this they require time-series climate surfaces of air temperature, humidity, wind speed, precipitation, and solar and thermal radiation. If data are available, these parameters can be adequately estimated at time steps of one to three hours. Unfortunately, climate monitoring in mountain basins is very limited, and the full range of elevations and exposures that affect climate conditions, snow deposition, and melt is seldom sampled. Detailed time-series climate surfaces have been successfully developed using limited data and relatively simple methods. We present a synopsis of the tools and methods used to combine limited data with simple corrections for the topographic controls to generate high temporal resolution time-series images of these climate parameters. Methods used include simulations, elevational gradients, and detrended kriging. The generated climate surfaces are evaluated at points and spatially to determine if they are reasonable approximations of actual conditions. Recommendations are made for the addition of critical parameters and measurement sites into routine monitoring systems in mountain basins.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Zhang, D.
Radiation dose monitoring solutions have opened up new opportunities for medical physicists to be more involved in modern clinical radiology practices. In particular, with the help of comprehensive radiation dose data, data-driven protocol management and informed case follow up are now feasible. Significant challenges remain however and the problems faced by medical physicists are highly heterogeneous. Imaging systems from multiple vendors and a wide range of vintages co-exist in the same department and employ data communication protocols that are not fully standardized or implemented making harmonization complex. Many different solutions for radiation dose monitoring have been implemented by imaging facilitiesmore » over the past few years. Such systems are based on commercial software, home-grown IT solutions, manual PACS data dumping, etc., and diverse pathways can be used to bring the data to impact clinical practice. The speakers will share their experiences with creating or tailoring radiation dose monitoring/management systems and procedures over the past few years, which vary significantly in design and scope. Topics to cover: (1) fluoroscopic dose monitoring and high radiation event handling from a large academic hospital; (2) dose monitoring and protocol optimization in pediatric radiology; and (3) development of a home-grown IT solution and dose data analysis framework. Learning Objectives: Describe the scope and range of radiation dose monitoring and protocol management in a modern radiology practice Review examples of data available from a variety of systems and how it managed and conveyed. Reflect on the role of the physicist in radiation dose awareness.« less
78 FR 64030 - Monitoring Criteria and Methods To Calculate Occupational Radiation Doses
Federal Register 2010, 2011, 2012, 2013, 2014
2013-10-25
... NUCLEAR REGULATORY COMMISSION [NRC-2013-0234] Monitoring Criteria and Methods To Calculate... regulatory guide (DG), DG-8031, ``Monitoring Criteria and Methods to Calculate Occupational Radiation Doses.'' This guide describes methods that the NRC staff considers acceptable for licensees to use to determine...
Nomura, Shuhei; Tsubokura, Masaharu; Ozaki, Akihiko; Murakami, Michio; Hodgson, Susan; Blangiardo, Marta; Nishikawa, Yoshitaka; Morita, Tomohiro; Oikawa, Tomoyoshi
2017-04-09
Following Japan's 2011 Fukushima nuclear incident, we assessed voluntary-based monitoring behavior in Minamisoma City-located 10-40 km from the Fukushima nuclear plant-to inform future monitoring strategies. The monitoring in Minamisoma included occasional free of charge internal-radiation-exposure measurements. Out of around 70,000 individuals residing in the city before the incident, a total of 45,788 residents (female: 52.1%) aged ≥21 were evaluated. The monitoring prevalence in 2011-2012 was only 30.2%, and this decreased to 17.9% in 2013-2014. Regression analyses were performed to estimate factors associated with the monitoring prevalence and participation behavior. The results show that, in comparison with the age cohort of 21-30 years, the cohort of 71-80 and ≥81 years demonstrated significantly lower monitoring prevalence; female residents had higher monitoring prevalence than male residents; those who were living in evacuation zones at the time of the incident had higher monitoring prevalence than those who lived outside any of the evacuation zones; for those living outside Fukushima and neighboring Prefectures post-incident monitoring prevalence decreased significantly in 2013-2014. Our findings inform the discussion on the concepts of radiation risk perception and accessibility to monitoring and societal decision-making regarding the maintenance of the monitoring program with low monitoring prevalence. We also stress the possibility that the monitoring can work both to check that internal contamination levels are within acceptable limits, and as a risk communication tool, alleviating individuals' concern and anxiety over radiation contamination.
Cherenkov imaging and biochemical sensing in vivo during radiation therapy
NASA Astrophysics Data System (ADS)
Zhang, Rongxiao
While Cherenkov emission was discovered more than eighty years ago, the potential applications of imaging this during radiation therapy have just recently been explored. With approximately half of all cancer patients being treated by radiation at some point during their cancer management, there is a constant challenge to ensure optimal treatment efficiency is achieved with maximal tumor to normal tissue therapeutic ratio. To achieve this, the treatment process as well as biological information affecting the treatment should ideally be effective and directly derived from the delivery of radiation to the patient. The value of Cherenkov emission imaging was examined here, primarily for visualization of treatment monitoring and then secondarily for Cherenkov-excited luminescence for tissue biochemical sensing within tissue. Through synchronized gating to the short radiation pulses of a linear accelerator (200Hz & 3 micros pulses), and applying a gated intensified camera for imaging, the Cherenkov radiation can be captured near video frame rates (30 frame per sec) with dim ambient room lighting. This procedure, sometimes termed Cherenkoscopy, is readily visualized without affecting the normal process of external beam radiation therapy. With simulation, phantoms and clinical trial data, each application of Cherenkoscopy was examined: i) for treatment monitoring, ii) for patient position monitoring and motion tracking, and iii) for superficial dose imaging. The temporal dynamics of delivered radiation fields can easily be directly imaged on the patient's surface. Image registration and edge detection of Cherenkov images were used to verify patient positioning during treatment. Inter-fraction setup accuracy and intra-fraction patient motion was detectable to better than 1 mm accuracy. Cherenkov emission in tissue opens up a new field of biochemical sensing within the tissue environment, using luminescent agents which can be activated by this light. In the first study of its kind with external beam irradiation, a dendritic platinum-based phosphor (PtG4) was used at micro-molar concentrations (~5 microM) to generate Cherenkov-induced luminescent signals, which are sensitive to the partial pressure of oxygen. Both tomographic reconstruction methods and linear scanned imaging were investigated here to examine the limits of detection. Recovery of optical molecular distributions was shown in tissue phantoms and small animals, with high accuracy (~1 microM), high spatial resolution (~0.2 mm) and deep-tissue detectability (~2 cm for Cherenkov luminescence scanned imaging (CELSI)), indicating potentials for in vivo and clinical use. In summary, many of the physical and technological details of Cherenkov imaging and Cherenkov-excited emission imaging were specified in this study.
Radiation area monitor device and method
DOE Office of Scientific and Technical Information (OSTI.GOV)
Vencelj, Matjaz; Stowe, Ashley C.; Petrovic, Toni
A radiation area monitor device/method, utilizing: a radiation sensor having a directional radiation sensing capability; a rotation mechanism operable for selectively rotating the radiation sensor such that the directional radiation sensing capability selectively sweeps an area of interest; and a processor operable for analyzing and storing a radiation fingerprint acquired by the radiation sensor as the directional radiation sensing capability selectively sweeps the area of interest. Optionally, the radiation sensor includes a gamma and/or neutron radiation sensor. The device/method selectively operates in: a first supervised mode during which a baseline radiation fingerprint is acquired by the radiation sensor; and amore » second unsupervised mode during which a subsequent radiation fingerprint is acquired by the radiation sensor, wherein the subsequent radiation fingerprint is compared to the baseline radiation fingerprint and, if a predetermined difference threshold is exceeded, an alert is issued.« less
Operational Prototype Development of a Global Aircraft Radiation Exposure Nowcast
NASA Astrophysics Data System (ADS)
Mertens, Christopher; Kress, Brian; Wiltberger, Michael; Tobiska, W. Kent; Bouwer, Dave
Galactic cosmic rays (GCR) and solar energetic particles (SEP) are the primary sources of human exposure to high linear energy transfer (LET) radiation in the atmosphere. High-LET radiation is effective at directly breaking DNA strands in biological tissue, or producing chemically active radicals in tissue that alter the cell function, both of which can lead to cancer or other adverse health effects. A prototype operational nowcast model of air-crew radiation exposure is currently under development and funded by NASA. The model predicts air-crew radiation exposure levels from both GCR and SEP that may accompany solar storms. The new air-crew radiation exposure model is called the Nowcast of Atmospheric Ionizing Radiation for Aviation Safety (NAIRAS) model. NAIRAS will provide global, data-driven, real-time exposure predictions of biologically harmful radiation at aviation altitudes. Observations are utilized from the ground (neutron monitors), from the atmosphere (the NCEP Global Forecast System), and from space (NASA/ACE and NOAA/GOES). Atmospheric observations characterize the overhead mass shielding and the ground-and space-based observations provide boundary conditions on the incident GCR and SEP particle flux distributions for transport and dosimetry calculations. Radiation exposure rates are calculated using the NASA physics-based HZETRN (High Charge (Z) and Energy TRaNsport) code. An overview of the NAIRAS model is given: the concept, design, prototype implementation status, data access, and example results. Issues encountered thus far and known and/or anticipated hurdles to research to operations transition are also discussed.
Radioactive materials in recycled metals.
Lubenau, J O; Yusko, J G
1995-04-01
In recent years, the metal recycling industry has become increasingly aware of an unwanted component in metal scrap--radioactive material. Worldwide, there have been 35 instances where radioactive sources were unintentionally smelted in the course of recycling metal scrap. In some cases contaminated metal consumer products were distributed internationally. In at least one case, serious radiation exposures of workers and the public occurred. Radioactive material appearing in metal scrap includes sources subject to licensing under the Atomic Energy Act and also naturally occurring radioactive material. U.S. mills that have smelted a radioactive source face costs resulting from decontamination, waste disposal, and lost profits that range from 7 to 23 million U.S. dollars for each event. To solve the problem, industry and the government have jointly undertaken initiatives to increase awareness of the problem within the metal recycling industry. Radiation monitoring of recycled metal scrap is being performed increasingly by mills and, to a lesser extent, by scrap processors. The monitoring does not, however, provide 100% protection. Improvements in regulatory oversight by the government could stimulate improved accounting and control of licensed sources. However, additional government effort in this area must be reconciled with competing priorities in radiation safety and budgetary constraints. The threat of radioactive material in recycled metal scrap will continue for the foreseeable future and, thus, poses regulatory policy challenges for both developed and developing nations.
Cyber-Physical Trade-Offs in Distributed Detection Networks
DOE Office of Scientific and Technical Information (OSTI.GOV)
Rao, Nageswara S; Yao, David K. Y.; Chin, J. C.
2010-01-01
We consider a network of sensors that measure the scalar intensity due to the background or a source combined with background, inside a two-dimensional monitoring area. The sensor measurements may be random due to the underlying nature of the source and background or due to sensor errors or both. The detection problem is infer the presence of a source of unknown intensity and location based on sensor measurements. In the conventional approach, detection decisions are made at the individual sensors, which are then combined at the fusion center, for example using the majority rule. With increased communication and computation costs,more » we show that a more complex fusion algorithm based on measurements achieves better detection performance under smooth and non-smooth source intensity functions, Lipschitz conditions on probability ratios and a minimum packing number for the state-space. We show that these conditions for trade-offs between the cyber costs and physical detection performance are applicable for two detection problems: (i) point radiation sources amidst background radiation, and (ii) sources and background with Gaussian distributions.« less
Contribution for Iron Vapor and Radiation Distribution Affected by Current Frequency of Pulsed Arc
NASA Astrophysics Data System (ADS)
Shimokura, Takuya; Mori, Yusuke; Iwao, Toru; Yumoto, Motoshige
Pulsed GTA welding has been used for improvement of stability, weld speed, and heat input control. However, the temperature and radiation power of the pulsed arc have not been elucidated. Furthermore, arc contamination by metal vapor changes the arc characteristics, e.g. by increasing radiation power. In this case, the metal vapor in pulsed GTA welding changes the distribution of temperature and radiation power as a function of time. This paper presents the relation between metal vapor and radiation power at different pulse frequencies. We calculate the Fe vapor distribution of the pulsed current. Results show that the Fe vapor is transported at fast arc velocity during the peak current period. During the base current period, the Fe vapor concentration is low and distribution is diffuse. The transition of Fe vapor distribution does not follow the pulsed current; the radiation power density distribution differs for high frequencies and low frequencies. In addition, the Fe vapor and radiation distribution are affected by the pulsed arc current frequency.
NASA Technical Reports Server (NTRS)
Stevenson, William A. (Inventor)
1989-01-01
A process for infrared spectroscopic monitoring of insitu compositional changes in a polymeric material comprises the steps of providing an elongated infrared radiation transmitting fiber that has a transmission portion and a sensor portion, embedding the sensor portion in the polymeric material to be monitored, subjecting the polymeric material to a processing sequence, applying a beam of infrared radiation to the fiber for transmission through the transmitting portion to the sensor portion for modification as a function of properties of the polymeric material, monitoring the modified infrared radiation spectra as the polymeric material is being subjected to the processing sequence to obtain kinetic data on changes in the polymeric material during the processing sequence, and adjusting the processing sequence as a function of the kinetic data provided by the modified infrared radiation spectra information.
NASA Technical Reports Server (NTRS)
Stevenson, William A. (Inventor)
1992-01-01
A process for infrared spectroscopic monitoring of insitu compositional changes in a polymeric material comprises the steps of providing an elongated infrared radiation transmitting fiber that has a transmission portion and a sensor portion, embedding the sensor portion in the polymeric material to be monitored, subjecting the polymeric material to a processing sequence, applying a beam of infrared radiation to the fiber for transmission through the transmitting portion to the sensor portion for modification as a function of properties of the polymeric material, monitoring the modified infrared radiation spectra as the polymeric material is being subjected to the processing sequence to obtain kinetic data on changes in the polymeric material during the processing sequence, and adjusting the processing sequence as a function of the kinetic data provided by the modified infrared radiation spectra information.
A principal activity of the Offsite Radiological Safety Program is routine environmental monitoring for radioactive materials in various media and for radiation in areas which may be affected by nuclear tests. It is conducted to document compliance with standards, to identify tre...
10 CFR 39.65 - Personnel monitoring.
Code of Federal Regulations, 2014 CFR
2014-01-01
... 10 Energy 1 2014-01-01 2014-01-01 false Personnel monitoring. 39.65 Section 39.65 Energy NUCLEAR REGULATORY COMMISSION LICENSES AND RADIATION SAFETY REQUIREMENTS FOR WELL LOGGING Radiation Safety Requirements § 39.65 Personnel monitoring. (a) The licensee may not permit an individual to act as a logging...
10 CFR 39.65 - Personnel monitoring.
Code of Federal Regulations, 2011 CFR
2011-01-01
... 10 Energy 1 2011-01-01 2011-01-01 false Personnel monitoring. 39.65 Section 39.65 Energy NUCLEAR REGULATORY COMMISSION LICENSES AND RADIATION SAFETY REQUIREMENTS FOR WELL LOGGING Radiation Safety Requirements § 39.65 Personnel monitoring. (a) The licensee may not permit an individual to act as a logging...
10 CFR 39.65 - Personnel monitoring.
Code of Federal Regulations, 2013 CFR
2013-01-01
... 10 Energy 1 2013-01-01 2013-01-01 false Personnel monitoring. 39.65 Section 39.65 Energy NUCLEAR REGULATORY COMMISSION LICENSES AND RADIATION SAFETY REQUIREMENTS FOR WELL LOGGING Radiation Safety Requirements § 39.65 Personnel monitoring. (a) The licensee may not permit an individual to act as a logging...
10 CFR 39.65 - Personnel monitoring.
Code of Federal Regulations, 2010 CFR
2010-01-01
... 10 Energy 1 2010-01-01 2010-01-01 false Personnel monitoring. 39.65 Section 39.65 Energy NUCLEAR REGULATORY COMMISSION LICENSES AND RADIATION SAFETY REQUIREMENTS FOR WELL LOGGING Radiation Safety Requirements § 39.65 Personnel monitoring. (a) The licensee may not permit an individual to act as a logging...
10 CFR 39.65 - Personnel monitoring.
Code of Federal Regulations, 2012 CFR
2012-01-01
... 10 Energy 1 2012-01-01 2012-01-01 false Personnel monitoring. 39.65 Section 39.65 Energy NUCLEAR REGULATORY COMMISSION LICENSES AND RADIATION SAFETY REQUIREMENTS FOR WELL LOGGING Radiation Safety Requirements § 39.65 Personnel monitoring. (a) The licensee may not permit an individual to act as a logging...
The development of remote wireless radiation dose monitoring system
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lee, Jin-woo; Chonbuk National University, Jeonjoo-Si; Jeong, Kyu-hwan
Internet of things (IoT) technology has recently shown a large flow of IT trends in human life. In particular, our lives are now becoming integrated with a lot of items around the 'smart-phone' with IoT, including Bluetooth, Near Field Communication (NFC), Beacons, WiFi, and Global Positioning System (GPS). Our project focuses on the interconnection of radiation dosimetry and IoT technology. The radiation workers at a nuclear facility should hold personal dosimeters such as a Thermo-Luminescence Dosimeter (TLD), an Optically Stimulated Luminescence Dosimeter (OSL), pocket ionization chamber dosimeters, an Electronic Personal Dosimeter (EPD), or an alarm dosimeter on their body. Somemore » of them have functions that generate audible or visible alarms to radiation workers in a real working area. However, such devices used in radiation fields these days have no functions for communicating with other areas or the responsible personnel in real time. In particular, when conducting a particular task in a high dose area, or a number of repair works within a radiation field, radiation dose monitoring is important for the health of the workers and the work efficiency. Our project aims at the development of a remote wireless radiation dose monitoring system (RWRD) that can be used to monitor the radiation dose in a nuclear facility for radiation workers and a radiation protection program In this project, a radiation dosimeter is the detection device for personal radiation dose, a smart phone is the mobile wireless communication tool, and, Beacon is the wireless starter for the detection, communication, and position of the worker using BLE (Bluetooth Low Energy). In this report, we report the design of the RWRD and a demonstration case in a real radiation field. (authors)« less
Radiation area monitor device and method
DOE Office of Scientific and Technical Information (OSTI.GOV)
Vencelj, Matjaz; Stowe, Ashley C.; Petrovic, Toni
A radiation area monitor device/method, utilizing: a radiation sensor; a rotating radiation shield disposed about the radiation sensor, wherein the rotating radiation shield defines one or more ports that are transparent to radiation; and a processor operable for analyzing and storing a radiation fingerprint acquired by the radiation sensor as the rotating radiation shield is rotated about the radiation sensor. Optionally, the radiation sensor includes a gamma and/or neutron radiation sensor. The device/method selectively operates in: a first supervised mode during which a baseline radiation fingerprint is acquired by the radiation sensor as the rotating radiation shield is rotated aboutmore » the radiation sensor; and a second unsupervised mode during which a subsequent radiation fingerprint is acquired by the radiation sensor as the rotating radiation shield is rotated about the radiation sensor, wherein the subsequent radiation fingerprint is compared to the baseline radiation fingerprint and, if a predetermined difference threshold is exceeded, an alert is issued.« less
Simulation and Comparison of Martian Surface Ionization Radiation
NASA Technical Reports Server (NTRS)
Kim, Myung-Hee Y.; Zeitlin, Cary; Hassler, Donald M.; Cucinotta, Francis A.
2013-01-01
The spectrum of energetic particle radiation and corresponding doses at the surface of Mars is being characterized by the Radiation Assessment Detector (RAD), one of ten science instruments on the Mars Science Laboratory (MSL) Curiosity Rover. The time series of dose rate for the first 300 Sols after landing on Mars on August 6, 2012 is presented here. For the comparison to RAD measurements of dose rate, Martian surface ionization radiation is simulated by utilizing observed space quantities. The GCR primary radiation spectrum is calculated by using the Badhwar-O'Neill 2011 (BO11) galactic cosmic ray (GCR) model, which has been developed by utilizing all balloon and satellite GCR measurements since 1955 and the newer 1997-2012 Advanced Composition Explorer (ACE) measurements. In the BO11 model, solar modulation of the GCR primary radiation spectrum is described in terms of the international smoothed sunspot number and a time delay function. For the transport of the impingent GCR primary radiation through Mars atmosphere, a vertical distribution of atmospheric thickness at each elevation is calculated using the vertical profiles of atmospheric temperature and pressure made by Mars Global Surveyor measurements. At Gale Crater in the southern hemisphere, the seasonal variation of atmospheric thickness is accounted for the daily atmospheric pressure measurements of the MSL Rover Environmental Monitoring Station (REMS) by using low- and high-density models for cool- and warm-season, respectively. The spherically distributed atmospheric distance is traced along the slant path, and the resultant directional shielding by Martian atmosphere is coupled with Curiosity vehicle for dose estimates. We present predictions of dose rate and comparison to the RAD measurements. The simulation agrees to within +/- 20% with the RAD measurements showing clearly the variation of dose rate by heliospheric conditions, and presenting the sensitivity of dose rate by atmospheric pressure, which has been found from the RAD experiments and driven by thermal tides on Martian surface.
Corrosive effect of environmental change on selected properties of polymer composites
NASA Astrophysics Data System (ADS)
Markovičová, L.; Zatkalíková, V.
2017-11-01
The development of composite materials and the related design and manufacturing technologies is one of the most important advances in the history of materials. Composites are multifunctional materials having unprecedented mechanical and physical properties that can be tailored to meet the requirements of a particular application. Ageing is also important and it is defined as the process of deterioration of engineering materials resulting from the combined effects of atmospheric radiation, heat, oxygen, water, micro-organisms and other atmospheric factors. The present article deals with monitoring the changes in the mechanical properties of composites with polymer matrix. The composite was formed from the PA matrix and glass fibers (GF). The composite contains 10, 20 and 30 % of glass fibers. The mechanical properties were evaluated on samples of the composite before and after UV radiation on the sample. Light microscopy was evaluated distribution of glass fibers in the polymer matrix and the presence of cracks caused by UV radiation.
NASA Astrophysics Data System (ADS)
Daglis, I. A.; Georgiou, M.; Zesta, E.; Balasis, G.; Tsinganos, K.
2013-12-01
This paper addresses the question whether radiation belt electron enhancements are associated with ultra-low frequency (ULF) wave power penetrating to lower L-shells during intense geospace magnetic storms. We have examined the variation of relativistic electron fluxes in the inner magnetosphere during small, moderate, and intense storms and have compared them with concurrent variations of the power of Pc 4-5 waves, using multi-point wave observations from the IMAGE and CARISMA ground-based magnetometer arrays. We discuss the excitation, growth and decay characteristics of Pc 4-5 waves during the different phases of the three classes of magnetic storms, with particular emphasis on the distribution of wave power over a range of L shells. The work leading to this paper has received funding from the European Union's Seventh Framework Programme (FP7-SPACE-2011-1) under grant agreement no. 284520 for the MAARBLE (Monitoring, Analyzing and Assessing Radiation Belt Energization and Loss) collaborative research project.
NASA Technical Reports Server (NTRS)
Fasnacht, Zachary; Qin, Wenhan; Haffner, David P.; Loyola, Diego; Joiner, Joanna; Krotkov, Nickolay; Vasilkov, Alexander; Spurr, Robert
2017-01-01
Surface Lambertian-equivalent reflectivity (LER) is important for trace gas retrievals in the direct calculation of cloud fractions and indirect calculation of the air mass factor. Current trace gas retrievals use climatological surface LER's. Surface properties that impact the bidirectional reflectance distribution function (BRDF) as well as varying satellite viewing geometry can be important for retrieval of trace gases. Geometry Dependent LER (GLER) captures these effects with its calculation of sun normalized radiances (I/F) and can be used in current LER algorithms (Vasilkov et al. 2016). Pixel by pixel radiative transfer calculations are computationally expensive for large datasets. Modern satellite missions such as the Tropospheric Monitoring Instrument (TROPOMI) produce very large datasets as they take measurements at much higher spatial and spectral resolutions. Look up table (LUT) interpolation improves the speed of radiative transfer calculations but complexity increases for non-linear functions. Neural networks perform fast calculations and can accurately predict both non-linear and linear functions with little effort.
Bingham, Eula; Ringen, Knut; Dement, John; Cameron, Wilfrid; McGowan, William; Welch, Laura; Quinn, Patricia
2006-09-01
Construction workers were and are considered temporary workers at many construction sites. Since World War II, large numbers of construction workers were employed at U.S. Department of Energy nuclear weapons sites for periods ranging from a few days to over 30 years. These workers performed tasks during new construction and maintenance, repair, renovation, and demolition of existing facilities. Such tasks may involve emergency situations, and may entail opportunities for significant radiation exposures. This paper provides data from interviews with more than 750 construction workers at two gaseous diffusion plants (GDPs) at Paducah, Kentucky, and Portsmouth, Ohio regarding radiation monitoring practices. The aim was to determine the extent to which workers believed they were monitored during tasks involving potential radiation exposures. The adequacy of monitoring practices is important for two reasons: (a) Protecting workers from exposures: Construction workers were employed by sub-contractors, and may frequently been excluded from safety and health programs provided to permanent employees; and (b) Supporting claims for compensation: The Energy Employees Occupational Illness Compensation Program Act (EEOICPA) requires dose reconstruction of radiation exposures for most workers who file a claim regarding cancer. The use of monitoring data for radiation to qualify a worker means that there should be valid and complete monitoring during the work time at the various nuclear plants or workers may be unfairly denied compensation. The worker interviews from Paducah and Portsmouth were considered especially useful because these sites were designated as Special Exposure Cohorts (SECs) and the workers did not have to have a dose reconstruction to qualify for compensation for most cancers. Therefore, their responses were less likely to be affected by compensation concerns. Interview questions included asking for information regarding whether monitoring was performed, how often, and the maintenance (calibration) of monitoring equipment (devices).
Evaluation of Shiryaev-Roberts procedure for on-line environmental radiation monitoring.
Watson, Mara M; Seliman, Ayman F; Bliznyuk, Valery N; DeVol, Timothy A
2018-04-30
Water can become contaminated as a result of a leak from a nuclear facility, such as a waste facility, or from clandestine nuclear activity. Low-level on-line radiation monitoring is needed to detect these events in real time. A Bayesian control chart method, Shiryaev-Roberts (SR) procedure, was compared with classical methods, 3-σ and cumulative sum (CUSUM), for quantifying an accumulating signal from an extractive scintillating resin flow-cell detection system. Solutions containing 0.10-5.0 Bq/L of 99 Tc, as T99cO 4 - were pumped through a flow cell packed with extractive scintillating resin used in conjunction with a Beta-RAM Model 5 HPLC detector. While T99cO 4 - accumulated on the resin, time series data were collected. Control chart methods were applied to the data using statistical algorithms developed in MATLAB. SR charts were constructed using Poisson (Poisson SR) and Gaussian (Gaussian SR) probability distributions of count data to estimate the likelihood ratio. Poisson and Gaussian SR charts required less volume of radioactive solution at a fixed concentration to exceed the control limit in most cases than 3-σ and CUSUM control charts, particularly solutions with lower activity. SR is thus the ideal control chart for low-level on-line radiation monitoring. Once the control limit was exceeded, activity concentrations were estimated from the SR control chart using the control chart slope on a semi-logarithmic plot. A linear regression fit was applied to averaged slope data for five activity concentration groupings for Poisson and Gaussian SR control charts. A correlation coefficient (R 2 ) of 0.77 for Poisson SR and 0.90 for Gaussian SR suggest this method will adequately estimate activity concentration for an unknown solution. Copyright © 2018 Elsevier Ltd. All rights reserved.
Evaluation of Shiryaev-Roberts Procedure for On-line Environmental Radiation Monitoring
NASA Astrophysics Data System (ADS)
Watson, Mara Mae
An on-line radiation monitoring system that simultaneously concentrates and detects radioactivity is needed to detect an accidental leakage from a nuclear waste disposal facility or clandestine nuclear activity. Previous studies have shown that classical control chart methods can be applied to on-line radiation monitoring data to quickly detect these events as they occur; however, Bayesian control chart methods were not included in these studies. This work will evaluate the performance of a Bayesian control chart method, the Shiryaev-Roberts (SR) procedure, compared to classical control chart methods, Shewhart 3-sigma and cumulative sum (CUSUM), for use in on-line radiation monitoring of 99Tc in water using extractive scintillating resin. Measurements were collected by pumping solutions containing 0.1-5 Bq/L of 99Tc, as 99T cO4-, through a flow cell packed with extractive scintillating resin coupled to a Beta-RAM Model 5 HPLC detector. While 99T cO4- accumulated on the resin, simultaneous measurements were acquired in 10-s intervals and then re-binned to 100-s intervals. The Bayesian statistical method, Shiryaev-Roberts procedure, and classical control chart methods, Shewhart 3-sigma and cumulative sum (CUSUM), were applied to the data using statistical algorithms developed in MATLAB RTM. Two SR control charts were constructed using Poisson distributions and Gaussian distributions to estimate the likelihood ratio, and are referred to as Poisson SR and Gaussian SR to indicate the distribution used to calculate the statistic. The Poisson and Gaussian SR methods required as little as 28.9 mL less solution at 5 Bq/L and as much as 170 mL less solution at 0.5 Bq/L to exceed the control limit than the Shewhart 3-sigma method. The Poisson SR method needed as little as 6.20 mL less solution at 5 Bq/L and up to 125 mL less solution at 0.5 Bq/L to exceed the control limit than the CUSUM method. The Gaussian SR and CUSUM method required comparable solution volumes for test solutions containing at least 1.5 Bq/L of 99T c. For activity concentrations less than 1.5 Bq/L, the Gaussian SR method required as much as 40.8 mL less solution at 0.5 Bq/L to exceed the control limit than the CUSUM method. Both SR methods were able to consistently detect test solutions containing 0.1 Bq/L, unlike the Shewhart 3-sigma and CUSUM methods. Although the Poisson SR method required as much as 178 mL less solution to exceed the control limit than the Gaussian SR method, the Gaussian SR false positive of 0% was much lower than the Poisson SR false positive rate of 1.14%. A lower false positive rate made it easier to differentiate between a false positive and an increase in mean count rate caused by activity accumulating on the resin. The SR procedure is thus the ideal tool for low-level on-line radiation monitoring using extractive scintillating resin, because it needed less volume in most cases to detect an upward shift in the mean count rate than the Shewhart 3-sigma and CUSUM methods and consistently detected lower activity concentrations. The desired results for the monitoring scheme, however, need to be considered prior to choosing between the Poisson and Gaussian distribution to estimate the likelihood ratio, because each was advantageous under different circumstances. Once the control limit was exceeded, activity concentrations were estimated from the SR control chart using the slope of the control chart on a semi-logarithmic plot. Five of nine test solutions for the Poisson SR control chart produced concentration estimates within 30% of the actual value, but the worst case was 263.2% different than the actual value. The estimations for the Gaussian SR control chart were much more precise, with six of eight solutions producing estimates within 30%. Although the activity concentrations estimations were only mediocre for the Poisson SR control chart and satisfactory for the Gaussian SR control chart, these results demonstrate that a relationship exists between activity concentration and the SR control chart magnitude that can be exploited to determine the activity concentration from the SR control chart. More complex methods should be investigated to improve activity concentration estimations from the SR control charts.
Monitoring of fetal radiation exposure during pregnancy.
Chandra, Venita; Dorsey, Chelsea; Reed, Amy B; Shaw, Palma; Banghart, Dawn; Zhou, Wei
2013-09-01
One unique concern of vascular surgeons and trainees is radiation exposure associated with increased endovascular practice. The safety of childbearing is a particular worry for current and future women in vascular surgery. Little is known regarding actual fetal radiation exposure. This multi-institutional study aimed to evaluate the radiation dosages recorded on fetal dosimeter badges and compare them to external badges worn by the same cohort of women. All women who declared pregnancy with potential radiation exposure were required to wear two radiation monitors at each institution, one outside and the other inside the lead apron. Maternal (external) and fetal monitor dosimeter readings were analyzed. Maternal radiation exposures prior to, during, and postpregnancy were also assessed to determine any associated behavior modification. Eighty-one women declared pregnancy from 2008 to 2011 and 32 had regular radiation exposure during pregnancy. Maternal whole-body exposures ranged from 21-731 mrem. The average fetal dosimeter recordings for the cohort rounded to zero. Only two women had positive fetal dosimeter recordings; one had a single recording of 3 mrem and the other had a single recording of 7 mrem. There was no significant difference between maternal exposures prior to, during, and postpregnancy. Lack of knowledge of fetal radiation exposure has concerned many vascular surgeons, prompting them to wear double lead aprons during pregnancy, and perhaps prevented numerous other women from entering the field. Our study showed negligible radiation exposure on fetal monitoring suggesting that with the appropriate safety precautions, these concerns may be unwarranted. Published by Mosby, Inc.
Rizzolo, S; Périsse, J; Boukenter, A; Ouerdane, Y; Marin, E; Macé, J-R; Cannas, M; Girard, S
2017-08-18
We present an innovative architecture of a Rayleigh-based optical fibre sensor for the monitoring of water level and temperature inside storage nuclear fuel pools. This sensor, able to withstand the harsh constraints encountered under accidental conditions such as those pointed-out during the Fukushima-Daiichi event (temperature up to 100 °C and radiation dose level up to ~20 kGy), exploits the Optical Frequency Domain Reflectometry technique to remotely monitor a radiation resistant silica-based optical fibre i.e. its sensing probe. We validate the efficiency and the robustness of water level measurements, which are extrapolated from the temperature profile along the fibre length, in a dedicated test bench allowing the simulation of the environmental operating and accidental conditions. The conceived prototype ensures an easy, practical and no invasive integration into existing nuclear facilities. The obtained results represent a significant breakthrough and comfort the ability of the developed system to overcome both operating and accidental constraints providing the distributed profiles of the water level (0-to-5 m) and temperature (20-to-100 °C) with a resolution that in accidental condition is better than 3 cm and of ~0.5 °C respectively. These new sensors will be able, as safeguards, to contribute and reinforce the safety in existing and future nuclear power plants.
The status and prospective of environmental radiation monitoring stations in Saudi Arabia
NASA Astrophysics Data System (ADS)
Al-Kheliewi, Abdullah S.; Holzheimer, Clous
2014-09-01
The use of nuclear technology requires an environmental monitoring program to ensure the safety of the environment, and to protect people from the hazards of radioactive materials, and nuclear accidents. Nuclear accidents are unique, for they incur effects that surpass international frontiers, and can even have a long lasting impact on Earth. Such was the case of the Chernobyl accident in the Ukraine on April 6, 1986. For that purpose, international and national efforts come together to observe for any nuclear or radioactive accident. Many states, including Saudi Arabia which oversees the operation of the National Radiation, Environmental and Early Monitoring Stations, The Radiation Monitoring Stations(RMS's) are currently scattered across 35 cities in the country,. These locations are evaluated based on various technological criteria such as border cities, cities of high population density, wind direction, etc. For new nuclear power plants hovering around, it is strongly recommended to increase the number of radiation monitoring stations to warn against any threat that may arise from a nuclear leak or accident and to improve the performance of the existing RMS's. SARA (Spectroscopic Monitoring Station for air) should be implemented due to the high sensitivity to artificial radiation, automatic isotope identification, free of maintenance, and fully independent due to solar power supply (incl. battery backup) and wireless communication (GPRS).
Nomura, Shuhei; Tsubokura, Masaharu; Ozaki, Akihiko; Murakami, Michio; Hodgson, Susan; Blangiardo, Marta; Nishikawa, Yoshitaka; Morita, Tomohiro; Oikawa, Tomoyoshi
2017-01-01
Following Japan’s 2011 Fukushima nuclear incident, we assessed voluntary-based monitoring behavior in Minamisoma City—located 10–40 km from the Fukushima nuclear plant—to inform future monitoring strategies. The monitoring in Minamisoma included occasional free of charge internal-radiation-exposure measurements. Out of around 70,000 individuals residing in the city before the incident, a total of 45,788 residents (female: 52.1%) aged ≥21 were evaluated. The monitoring prevalence in 2011–2012 was only 30.2%, and this decreased to 17.9% in 2013–2014. Regression analyses were performed to estimate factors associated with the monitoring prevalence and participation behavior. The results show that, in comparison with the age cohort of 21–30 years, the cohort of 71–80 and ≥81 years demonstrated significantly lower monitoring prevalence; female residents had higher monitoring prevalence than male residents; those who were living in evacuation zones at the time of the incident had higher monitoring prevalence than those who lived outside any of the evacuation zones; for those living outside Fukushima and neighboring Prefectures post-incident monitoring prevalence decreased significantly in 2013–2014. Our findings inform the discussion on the concepts of radiation risk perception and accessibility to monitoring and societal decision-making regarding the maintenance of the monitoring program with low monitoring prevalence. We also stress the possibility that the monitoring can work both to check that internal contamination levels are within acceptable limits, and as a risk communication tool, alleviating individuals’ concern and anxiety over radiation contamination. PMID:28397769
Monitoring cosmic radiation on aircraft
NASA Astrophysics Data System (ADS)
Bentley, Robert D.; Iles, R. H. A.; Jones, J. B. L.; Hunter, R.; Taylor, G. C.; Thomas, D. J.
2002-03-01
The Earth is constantly bombarded by cosmic radiation that can be either galactic or solar in origin. At aircraft altitudes, the radiation levels are much higher than at sea level and recent European legislation has classified aircrew as radiation workers. University College London is working with Virgin Atlantic Airways on a 3 year project to monitor the levels of cosmic radiation on long-haul flights. The study will determine whether models currently used to predict radiation exposure of aircrew are adequate. It will also try to determine whether solar flare activity can cause significant enhancement to the predicted doses.
Brown Carbon and Black Carbon in the Smoky Atmosphere during Boreal Forest Fires
NASA Astrophysics Data System (ADS)
Gorchakov, G. I.; Karpov, A. V.; Pankratova, N. V.; Semoutnikova, E. G.; Vasiliev, A. V.; Gorchakova, I. A.
2017-12-01
We have investigated the variability of smoke aerosol absorbing ability with variations in the content of brown carbon (BrC) and black carbon (BC). Using monitoring data on radiative characteristics of smoke aerosol at AERONET stations and the spatial distribution of aerosol optical depth (AOD) obtained by the MODIS spectrometer ( Terra satellite), we have detected large-scale smokes during boreal forest fires in Russia and Canada (1995-2012). The spatial distribution (50°-70° N, 95°-125° W) and temporal variability (at AERONET station Fort McMurray) of AOD during the smoking of a part of Canada in July 2012 have been analyzed. AOD probability distributions for July 14-18, 2012, and an estimate of aerosol radiative forcing of smoke aerosol at the upper boundary of the atmosphere have been obtained. We have proposed a technique for the diagnostics of BrC and BC in smoke aerosol particles from the spectral dependence of the imaginary part of the refractive index. At a wavelength of 440 nm, the contributions of BrC and BC to the smokeaerosol absorbing abitity can be comparable in magnitude. In many cases, the absorption spectra of smoke aerosol can be adequately approximated by either power or exponential functions. The presence of BrC in smoke-aerosol particles highly extends the variety of observed absorption spectra in a smoky atmosphere and spectral dependences of single scattering albedo. In the spectral range of 440-1020 nm, the radiative characteristics of smoke aerosol are largely contributed by its fine mode.
NASA Astrophysics Data System (ADS)
Nishizawa, Yukiyasu; Sugita, Takeshi; Sanada, Yukihisa; Torii, Tatsuo
2015-04-01
Since 2011, MEXT (Ministry of Education, Culture, Sports, Science and Technology, Japan) have been conducting aerial monitoring to investigate the distribution of radioactive cesium dispersed into the atmosphere after the accident at the Fukushima Dai-ichi Nuclear Power Plant (FDNPP), Tokyo Electric Power Company. Distribution maps of the air dose-rate at 1 m above the ground and the radioactive cesium deposition concentration on the ground are prepared using spectrum obtained by aerial monitoring. The radioactive cesium deposition is derived from its dose rate, which is calculated by excluding the dose rate of the background radiation due to natural radionuclides from the air dose-rate at 1 m above the ground. The first step of the current method of calculating the dose rate due to natural radionuclides is calculate the ratio of the total count rate of areas where no radioactive cesium is detected and the count rate of regions with energy levels of 1,400 keV or higher (BG-Index). Next, calculate the air dose rate of radioactive cesium by multiplying the BG-Index and the integrated count rate of 1,400 keV or higher for the area where the radioactive cesium is distributed. In high dose-rate areas, however, the count rate of the 1,365-keV peak of Cs-134, though small, is included in the integrated count rate of 1,400 keV or higher, which could cause an overestimation of the air dose rate of natural radionuclides. We developed a method for accurately evaluating the distribution maps of natural air dose-rate by excluding the effect of radioactive cesium, even in contaminated areas, and obtained the accurate air dose-rate map attributed the radioactive cesium deposition on the ground. Furthermore, the natural dose-rate distribution throughout Japan has been obtained by this method.
Radiation monitoring in interventional cardiology: a requirement
NASA Astrophysics Data System (ADS)
Rivera, T.; Uruchurtu, E. S.
2017-01-01
The increasing of procedures using fluoroscopy in interventional cardiology procedures may increase medical and patients to levels of radiation that manifest in unintended outcomes. Such outcomes may include skin injury and cancer. The cardiologists and other staff members in interventional cardiology are usually working close to the area under examination and they receive the dose primarily from scattered radiation from the patient. Mexico does not have a formal policy for monitoring and recording the radiation dose delivered in hemodynamic establishments. Deterministic risk management can be improved by monitoring the radiation delivered from X-ray devices. The objective of this paper is to provide cardiologist, techniques, nurses, and all medical staff an information on DR levels, about X-ray risks and a simple a reliable method to control cumulative dose.
Environmental Radiation Data (ERD) Journal Report 161
RadNet environmental radiation monitoring data report for the period of January - March 2015. The report includes results for air, drinking water and precipitation samples collected as part of EPA's RadNet monitoring program.
Environmental Radiation Data (ERD) Journal Report 157
RadNet environmental radiation monitoring data report for the period of January - March 2014. The report includes results for air, drinking water, precipitation samples collected as part of EPA's RadNet monitoring program.
Environmental Radiation Data (ERD) Journal Report 162
RadNet environmental radiation monitoring data report for the period of April - June 2015. The report includes results for air, drinking water and precipitation samples collected as part of EPA's RadNet monitoring program.
Environmental Radiation Data (ERD) Journal Report 155
RadNet environmental radiation monitoring data report for the period of July - September 2013. The report includes results for air, drinking water, precipitation samples collected as part of EPA's RadNet monitoring program.
Environmental Radiation Data (ERD) Journal Report 154
RadNet environmental radiation monitoring data report for the period of April - June 2013. The report includes results for air, drinking water, precipitation samples collected as part of EPA's RadNet monitoring program.
Environmental Radiation Data (ERD) Journal Report 158
RadNet environmental radiation monitoring data report for the period of April - June 2014. The report includes results for air, drinking water, precipitation samples collected as part of EPA's RadNet monitoring program.
Environmental Radiation Data (ERD) Journal Report 163
RadNet environmental radiation monitoring data report for the period of July - September 2015. The report includes results for air, drinking water and precipitation samples collected as part of EPA's RadNet monitoring program.
Environmental Radiation Data (ERD) Journal Report 156
RadNet environmental radiation monitoring data report for the period of October - December 2013. The report includes results for air, drinking water, precipitation samples collected as part of EPA's RadNet monitoring program.
Environmental Radiation Data (ERD) Journal Report 159
RadNet environmental radiation monitoring data report for the period of July - September 2014. The report includes results for air, drinking water and precipitation samples collected as part of EPA's RadNet monitoring program.
Environmental Radiation Data (ERD) Journal Report 164
RadNet environmental radiation monitoring data report for the period of October - December 2015. The report includes results for air, drinking water and precipitation samples collected as part of EPA's RadNet monitoring program.
Environmental Radiation Data (ERD) Journal Report 160
RadNet environmental radiation monitoring data report for the period of October - December 2014. The report includes results for air, drinking water and precipitation samples collected as part of EPA's RadNet monitoring program.
Environmental Radiation Data (ERD) Journal Report 166
RadNet environmental radiation monitoring data report for the period of April - June 2016. The report includes results for air, drinking water and precipitation samples collected as part of EPA's RadNet monitoring program.
Environmental Radiation Data (ERD) Journal Report 165
RadNet environmental radiation monitoring data report for the period of January - March 2016. The report includes results for air, drinking water and precipitation samples collected as part of EPA's RadNet monitoring program.
International Radiation Monitoring and Information System (IRMIS)
NASA Astrophysics Data System (ADS)
Mukhopadhyay, Sanjoy; Baciu, Florian; Stowisek, Jan; Saluja, Gurdeep; Kenny, Patrick; Albinet, Franck
2017-09-01
This article describes the International Radiation Monitoring Information System (IRMIS) which was developed by the International Atomic Energy Agency (IAEA) with the goal to provide Competent Authorities, the IAEA and other international organizations with a client server based web application to share and visualize large quantities of radiation monitoring data. The data maps the areas of potential impact that can assist countries to take appropriate protective actions in an emergency. Ever since the Chernobyl nuclear power plant accident in April of 19861 European Community (EC) has worked towards collecting routine environmental radiological monitoring data from national networked monitoring systems. European Radiological Data Exchange Platform (EURDEP) was created in 19952 to that end - to provide radiation monitoring data from most European countries reported in nearly real-time. During the response operations for the Fukushima Dai-ichi nuclear power plant accident (March 2011) the IAEA Incident and Emergency Centre (IEC) managed, harmonized and shared the large amount of data that was being generated from different organizations. This task underscored the need for a system which allows sharing large volumes of radiation monitoring data in an emergency. In 2014 EURDEP started the submission of the European radiological data to the International Radiation Monitoring Information System (IRMIS) as a European Regional HUB for IRMIS. IRMIS supports the implementation of the Convention on Early Notification of a Nuclear Accident by providing a web application for the reporting, sharing, visualizing and analysing of large quantities of environmental radiation monitoring data during nuclear or radiological emergencies. IRMIS is not an early warning system that automatically reports when there are significant deviations in radiation levels or when values are detected above certain levels. However, the configuration of the visualization features offered by IRMIS may help Member States to determine where elevated gamma dose rate measurements during a radiological or nuclear emergency indicate that actions to protect the public are necessary. The data can be used to assist emergency responders determine where and when to take necessary actions to protect the public. This new web online tool supports the IAEA's Unified System for Information Exchange in Incidents and Emergencies (USIE)3, an online tool where competent authorities can access information about all emergency situations, ranging from a lost radioactive source to a full-scale nuclear emergency.
Denaï, Mouloud A; Mahfouf, Mahdi; Mohamad-Samuri, Suzani; Panoutsos, George; Brown, Brian H; Mills, Gary H
2010-05-01
Thoracic electrical impedance tomography (EIT) is a noninvasive, radiation-free monitoring technique whose aim is to reconstruct a cross-sectional image of the internal spatial distribution of conductivity from electrical measurements made by injecting small alternating currents via an electrode array placed on the surface of the thorax. The purpose of this paper is to discuss the fundamentals of EIT and demonstrate the principles of mechanical ventilation, lung recruitment, and EIT imaging on a comprehensive physiological model, which combines a model of respiratory mechanics, a model of the human lung absolute resistivity as a function of air content, and a 2-D finite-element mesh of the thorax to simulate EIT image reconstruction during mechanical ventilation. The overall model gives a good understanding of respiratory physiology and EIT monitoring techniques in mechanically ventilated patients. The model proposed here was able to reproduce consistent images of ventilation distribution in simulated acutely injured and collapsed lung conditions. A new advisory system architecture integrating a previously developed data-driven physiological model for continuous and noninvasive predictions of blood gas parameters with the regional lung function data/information generated from absolute EIT (aEIT) is proposed for monitoring and ventilator therapy management of critical care patients.
Radiation-Tolerance Assessment of a Redundant Wireless Device
NASA Astrophysics Data System (ADS)
Huang, Q.; Jiang, J.
2018-01-01
This paper presents a method to evaluate radiation-tolerance without physical tests for a commercial off-the-shelf (COTS)-based monitoring device for high level radiation fields, such as those found in post-accident conditions in a nuclear power plant (NPP). This paper specifically describes the analysis of radiation environment in a severe accident, radiation damages in electronics, and the redundant solution used to prolong the life of the system, as well as the evaluation method for radiation protection and the analysis method of system reliability. As a case study, a wireless monitoring device with redundant and diversified channels is evaluated by using the developed method. The study results and system assessment data show that, under the given radiation condition, performance of the redundant device is more reliable and more robust than those non-redundant devices. The developed redundant wireless monitoring device is therefore able to apply in those conditions (up to 10 M Rad (Si)) during a severe accident in a NPP.
Intracore and extracore examination of fiber gratings with coherent detection
NASA Astrophysics Data System (ADS)
Froggatt, Mark Earl
2001-06-01
This thesis introduces several new methods of measurement to aid in the production and evaluation of Bragg gratings in optical fiber. Five measurements are described: UV fringe visualization for grating production, weak grating measurement for distributed sensing, strong grating measurement for telecommunication applications, second harmonic grating measurement for grating chirp assessment, and grating visualization using radiation diffraction from strong Bragg gratings. The weak grating measurement for distributed strain sensing is a summary of work published prior to beginning the thesis research, and is provided for background purposes. The UV fringe visualization is accomplished by using a phase mask very close to the plane of the fiber to diffract the incoming beams used to write the Bragg grating into nearly parallel alignment, leading to macroscopic fringes indicative of the phase, frequency, amplitude, and contrast of the microscopic fringes incident on the fiber. The weak grating measurement uses Optical Frequency Domain Reflectometry (OFDR) to measure the spatial distribution of the coupling strength of weak gratings. Included in the description of the OFDR technique are recent advances in the precision monitoring of the emission wavelength of tunable lasers. The precise monitoring of wavelength is critical to the functioning of OFDR. The strong grating measurement is based on a modified form of OFDR and an analysis of the problem in the time and frequency domains to produce accurate measurements of both the reflection and transmission Transfer Functions for Bragg gratings. This measurement technique is also applicable to a wide variety of optical fiber devices, and is shown to be scalable to multiple port devices. The second-harmonic measurement for grating chirp analysis is similar to the weak grating measurement, but it was done at a wavelength resonant with the second- harmonic grating in the fiber-780 nm for 1550 nm reflection gratings. The second-harmonic grating results from nonlinearities in the grating growth process and, due to the great sensitivity of OFDR, is detectable for almost all fiber gratings. The grating visualization also uses half-wavelength (780 nm) illumination of the grating through the core. This technique uses the diffraction of light into the radiation modes to make the grating in the fiber externally visible. By operating near the perpendicular radiation condition, and introducing coherent counter- propagating light, the spatial frequency and the amplitude of the grating as functions of distance along the fiber can be measured. To better understand the radiation from Bragg gratings, a technique known as the Volume Current Method (VCM) was used to derive an expression for the radiation from a Bragg grating for all of the LP fiber modes.
ERIC Educational Resources Information Center
Chardenet, Kathleen A.
2016-01-01
Purpose: A real-time dose management system was used to determine if radiation exposure levels would decrease when providers were privy to their real-time radiation exposure levels. Six aggregate categories of providers were first blinded (phase 1) and subsequently made aware of their radiation exposure levels during electrophysiology procedures…
Current methods of monitoring radiation exposure from CT.
Talati, Ronak K; Dunkin, Jared; Parikh, Shrujal; Moore, William H
2013-09-01
Increased public and regulatory scrutiny of imaging-related radiation exposure requires familiarity with current dose-monitoring techniques and best practices. CT-related ionizing radiation exposure has been cited as the largest and fastest growing source of population-wide iatrogenic ionizing radiation exposure. Upcoming federal regulations require imaging centers to familiarize themselves with available dose-monitoring techniques and implement comprehensive strategies to track patient dose, with particular emphasis on CT. Because of institution-specific and vendor-specific technologies, there are significant barriers to adoption and implementation. In this article, the authors outline the core components of a universal dose-monitoring strategy and detail a few of the many available commercial platforms. In addition, the authors introduce a cloud-based hybrid model dose-tracking system with the goal of rapid implementation, multicenter scalability, real-time dose feedback for technologists, cumulative dose monitoring, and optional dose communication to patients and into the record; doing so results in improved patient loyalty, referring physician satisfaction, and opportunity for repeat business. Copyright © 2013 American College of Radiology. All rights reserved.
NASA Astrophysics Data System (ADS)
Iwasaki, Ryosuke; Takagi, Ryo; Tomiyasu, Kentaro; Yoshizawa, Shin; Umemura, Shin-ichiro
2017-07-01
The targeting of the ultrasound beam and the prediction of thermal lesion formation in advance are the requirements for monitoring high-intensity focused ultrasound (HIFU) treatment with safety and reproducibility. To visualize the HIFU focal zone, we utilized an acoustic radiation force impulse (ARFI) imaging-based method. After inducing displacements inside tissues with pulsed HIFU called the push pulse exposure, the distribution of axial displacements started expanding and moving. To acquire RF data immediately after and during the HIFU push pulse exposure to improve prediction accuracy, we attempted methods using extrapolation estimation and applying HIFU noise elimination. The distributions going back in the time domain from the end of push pulse exposure are in good agreement with tissue coagulation at the center. The results suggest that the proposed focal zone visualization employing pulsed HIFU entailing the high-speed ARFI imaging method is useful for the prediction of thermal coagulation in advance.
NASA Astrophysics Data System (ADS)
Salas-García, Irene; Fanjul-Vélez, Félix; Arce-Diego, José Luis
2012-03-01
The development of Photodynamic Therapy (PDT) predictive models has become a valuable tool for an optimal treatment planning, monitoring and dosimetry adjustment. A few attempts have achieved a quite complete characterization of the complex photochemical and photophysical processes involved, even taking into account superficial fluorescence in the target tissue. The present work is devoted to the application of a predictive PDT model to obtain fluorescence tomography information during PDT when applied to a skin disease. The model takes into account the optical radiation distribution, a non-homogeneous topical photosensitizer distribution, the time dependent photochemical interaction and the photosensitizer fluorescence emission. The results show the spatial evolution of the photosensitizer fluorescence emission and the amount of singlet oxygen produced during PDT. The depth dependent photosensitizer fluorescence emission obtained is essential to estimate the spatial photosensitizer concentration and its degradation due to photobleaching. As a consequence the proposed approach could be used to predict the photosensitizer fluorescence tomographic measurements during PDT. The singlet oxygen prediction could also be employed as a valuable tool to predict the short term treatment outcome.
The Global Positioning System constellation as a space weather monitor
NASA Astrophysics Data System (ADS)
Morley, S.; Henderson, M. G.; Woodroffe, J. R.; Brito, T. V.
2016-12-01
The Global Positioning System (GPS) satellites are distributed across six orbital planes and follow near-circular orbits, with a 12 hour period, at an altitude of approximately 20200 km. The six orbital planes are distributed around the Earth and are nominally inclined at 55 degrees. Energetic particle detectors have been flown on the GPS constellation for more than two decades; by February 2016 there were 23 GPS satellites equipped with energetic particle instrumentation. The Combined X-ray Dosimeter (CXD), which is flown on 21 GPS satellites, has recently been cross-calibrated against electron data from the Van Allen Probes mission, demonstrating its utility for scientific research and radiation environment specification. Recently electron and proton flux data from these instruments, for the month of January 2014, have been publicly released. We will describe the GPS constellation from the perspective of its use as a monitor for space weather, review some of the key scientific results enabled by these instruments and show some recent observations from the constellation, including the 2015 St. Patrick's Day storm. Using data from multiple satellite missions we describe the dynamics of this storm in detail.
Development of an alpha/beta/gamma detector for radiation monitoring
NASA Astrophysics Data System (ADS)
Yamamoto, Seiichi; Hatazawa, Jun
2011-11-01
For radiation monitoring at the site of nuclear power plant accidents such as Fukushima Daiichi, radiation detectors not only for gamma photons but also for alpha and beta particles are needed because some nuclear fission products emit beta particles and gamma photons and some nuclear fuels contain plutonium that emits alpha particles. We developed a radiation detector that can simultaneously monitor alpha and beta particles and gamma photons for radiation monitoring. The detector consists of three-layered scintillators optically coupled to each other and coupled to a photomultiplier tube. The first layer, which is made of a thin plastic scintillator (decay time: 2.4 ns), detects alpha particles. The second layer, which is made of a thin Gd2SiO5 (GSO) scintillator with 1.5 mol.% Ce (decay time: 35 ns), detects beta particles. The third layer made of a thin GSO scintillator with 0.4 mol.% Ce (decay time: 70 ns) detects gamma photons. By using pulse shape discrimination, the count rates of these layers can be separated. With individual irradiation of alpha and beta particles and gamma photons, the count rate of the first layer represented the alpha particles, the second layer represented the beta particles, and the third layer represented the gamma photons. Even with simultaneous irradiation of the alpha and beta particles and the gamma photons, these three types of radiation can be individually monitored using correction for the gamma detection efficiency of the second and third layers. Our developed alpha, beta, and gamma detector is simple and will be useful for radiation monitoring, especially at nuclear power plant accident sites or other applications where the simultaneous measurements of alpha and beta particles and gamma photons are required.
Development of an alpha/beta/gamma detector for radiation monitoring.
Yamamoto, Seiichi; Hatazawa, Jun
2011-11-01
For radiation monitoring at the site of nuclear power plant accidents such as Fukushima Daiichi, radiation detectors not only for gamma photons but also for alpha and beta particles are needed because some nuclear fission products emit beta particles and gamma photons and some nuclear fuels contain plutonium that emits alpha particles. We developed a radiation detector that can simultaneously monitor alpha and beta particles and gamma photons for radiation monitoring. The detector consists of three-layered scintillators optically coupled to each other and coupled to a photomultiplier tube. The first layer, which is made of a thin plastic scintillator (decay time: 2.4 ns), detects alpha particles. The second layer, which is made of a thin Gd(2)SiO(5) (GSO) scintillator with 1.5 mol.% Ce (decay time: 35 ns), detects beta particles. The third layer made of a thin GSO scintillator with 0.4 mol.% Ce (decay time: 70 ns) detects gamma photons. By using pulse shape discrimination, the count rates of these layers can be separated. With individual irradiation of alpha and beta particles and gamma photons, the count rate of the first layer represented the alpha particles, the second layer represented the beta particles, and the third layer represented the gamma photons. Even with simultaneous irradiation of the alpha and beta particles and the gamma photons, these three types of radiation can be individually monitored using correction for the gamma detection efficiency of the second and third layers. Our developed alpha, beta, and gamma detector is simple and will be useful for radiation monitoring, especially at nuclear power plant accident sites or other applications where the simultaneous measurements of alpha and beta particles and gamma photons are required. © 2011 American Institute of Physics
Results of neutron irradiation of GEM detector for plasma radiation detection
NASA Astrophysics Data System (ADS)
Jednorog, S.; Bienkowska, B.; Chernyshova, M.; Łaszynska, E.; Prokopowicz, R.; Ziołkowski, A.
2015-09-01
The detecting devices dedicated for plasma monitoring will be exposed for massive fluxes of neutron, photons as well as other rays that are components of fusion reactions and their product interactions with plasma itself or surroundings. In result detecting module metallic components will be activated becoming a source of radiation. Moreover, electronics components could change their electronic properties. The prototype GEM detector constructed for monitoring soft X-ray radiation in ITER oriented tokamaks was used for plasma monitoring during experimental campaign on tokamak ASDEX Upgrade. After that it became a source of gamma radiation caused by neutrons. The present work contains description of detector activation in the laboratory conditions.
The North American Amphibian Monitoring Program. [abstract
Griffin, J.
1998-01-01
The North American Amphibian Monitoring Program has been under development for the past three years. The monitoring strategy for NAAMP has five main prongs: terrestrial salamander surveys, calling surveys, aquatic surveys, western surveys, and atlassing. Of these five, calling surveys were selected as one of the first implementation priorities due to their friendliness to volunteers of varying knowledge levels, relative low cost, and the fact that several groups had already pioneered the techniques involved. While some states and provinces had implemented calling surveys prior to NAAMP, like WI and IL, most states and provinces had little or no history of state/provincewide amphibian monitoring. Thus, the majority of calling survey programs were initiated in the past two years. To assess the progress of this pilot phase, a program review was conducted on the status of the NAAMP calling survey program, and the results of that review will be presented at the meeting. Topics to be discussed include: who is doing what where, extent of route coverage, the continuing random route discussions, quality assurance, strengths and weaknesses of calling surveys, reliability of data, and directions for the future. In addition, a brief overview of the DISPro project will be included. DISPro is a new amphibian monitoring program in National Parks, funded by the Demonstration of Intensive Sites Program (DISPro) through the EPA and NPS. It will begin this year at Big Bend and Shenandoah National Parks. The purpose of the DISPro Amphibian Project will be to investigate relationships between environmental factors and stressors and the distribution, abundance, and health of amphibians in these National Parks. At each Park, amphibian long-term monitoring protocols will be tested, distributions and abundance of amphibians will be mapped, and field research experiments will be conducted to examine stressor effects on amphibians (e.g., ultraviolet radiation, contaminants, acidification).
an aerosol climatology optical properties and its associated direct radiative forcing
NASA Astrophysics Data System (ADS)
Kinne, Stefan
2010-05-01
Aerosol particles are quite complex in nature. Aerosol impacts on the distribution of radiative energy and on cloud microphysics have been debated climate impact issues. Here, a new aerosol-climatology is presented, combining the consistency and completeness of global modelling with quality data by ground-monitoring. It provides global monthly maps for spectral aerosol optical properties and for concentrations of CCN and IN. Based on the optical properties the aerosol direct forcing is determined. And with environmental data for clouds and estimates on the anthropogenic fraction from emission experiments with global modelling even the climate relevant aerosol direct forcing at the top of the atmosphere (ToA) is determined. This value is rather small near -0.2W/m2 with limited uncertainty estimated at (+/-0.3) due to uncertainties in aerosol absorption and underlying surface conditions or clouds.
The Vital Infrared to X-ray Link in the Sgr A* Accretion Flow
NASA Astrophysics Data System (ADS)
Fazio, Giovanni; Ashby, Matthew; Baganoff, Frederick; Becklin, Eric; Boyce, Hope; Carey, Sean; Gammie, Charles; Ghez, Andrea; Glaccum, William; Gurwell, Mark; Haggard, Daryl; Herrero-Illana, Ruben; Hora, Joseph; Ingalls, James; Lowrance, Patrick; Markoff, Sera; Marrone, Daniel; Morris, Mark; Narayan, Ramesh; Neilsen, Joseph; Ponti, Gabriele; Smith, Howard; Willner, Steven; Witzel, Gunther
2018-05-01
Black hole accretion drives extreme astrophysical phenomena in the universe. Sgr A*, the radiating counterpart of the nearest supermassive black hole, is highly variable, but sparse data and short observations have left its emission physics in question. Despite enormous advances in accretion models, physical description of the interacting radiation mechanisms is incomplete. The X-ray emission mechanism in particular remains unknown. Because the necessary information is contained in the time-dependent relation between X-ray and infrared emission, we have begun monitoring Sgr A* simultaneously with Chandra in X-rays and with Spitzer in the infrared. Defining the X-ray to infrared flux density ratio will allow the entire energy distribution to be understood. We therefore request two new 24-hour epochs of Spitzer monitoring at 4.5 microns simultaneous with Chandra time already approved. This will increase the exposure time for X-ray flares where the NIR state is known, moving us out of the realm of small-number statistics and enabling diagnostics of the true X-ray/IR ratio. Under current NASA plans, this will be the last chance for these valuable Spitzer+Chandra observations.
Schell, S; Wilkens, J J
2012-03-07
Laser-driven particle acceleration is a potentially cost-efficient and compact new technology that might replace synchrotrons or cyclotrons for future proton or heavy-ion radiation therapy. Since the energy spectrum of laser-accelerated particles is rather wide, compared to the monoenergetic beams of conventional machines, studies have proposed the usage of broader spectra for the treatment of at least certain parts of the target volume to make the process more efficient. The thereby introduced additional uncertainty in the applied energy spectrum is analysed in this note. It is shown that the uncertainty can be categorized into a change of the total number of particles, and a change in the energy distribution of the particles. The former one can be monitored by a simple fluence detector and cancels for a high number of statistically fluctuating shots. The latter one, the redistribution of a fixed number of particles to different energy bins in the window of transmitted energies of the energy selection system, only introduces smaller changes to the resulting depth dose curve. Therefore, it might not be necessary to monitor this uncertainty for all applied shots. These findings might enable an easier uncertainty management for particle therapy with broad energy spectra.
The NOAA Integrated Surface Irradiance Study (ISIS)-A New Surface Radiation Monitoring Program.
NASA Astrophysics Data System (ADS)
Hicks, B. B.; Deluisi, J. J.; Matt, D. R.
1996-12-01
This paper describes a new radiation monitoring program, the Integrated Surface Irradiance Study (ISIS), that builds upon and takes over from earlier NOAA networks monitoring components of solar radiation [both the visible component (SOLRAD) and the shortwave component that causes sunburn, UV-B] across the continental United States. ISIS is implemented in two levels. Level 1 addresses incoming radiation only, and level 2 addresses the surface radiation balance. Level 2 also constitutes the SURFRAD (Surface Radiation) program of the NOAA Office of Global Programs, specifically intended to provide radiation data to support large-scale hydrologic studies that will be conducted under the Global Energy and Water Cycle Experiment. Eventually, it is planned for level 2 sites to monitor all components of the surface energy balance. Both levels of ISIS will eventually measure both visible and UV radiation components. At present, there are nine sites that are considered to be at ISIS level 1 standard and an additional four level 2 SURFRAD sites. A 10th level 1 site will be in operation soon. Plans call for an increase in the number of sites of both kinds, up to about 15 ISIS sites, of which 6 will be at the SURFRAD level. Data are available via FTP at ftp.atdd.noaa.govlpublisis or at http://www.srrb.noaa.gov (level 2).
Updating the Synchrotron Radiation Monitor at TLS
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kuo, C. H.; Hsu, S. Y.; Wang, C. J.
2007-01-19
The synchrotron radiation monitor provides useful information to support routine operation and physics experiments using the beam. Precisely knowing the profile of the beam helps to improve machine performance. The synchrotron radiation monitor at the Taiwan Light Source (TLS) was recently upgraded. The optics and modeling were improved to increase the accuracy of measurement in the small beam size. A high-performance IEEE-1394 digital CCD camera was used to improve the quality of images and extend the dynamic range of measurement. The image analysis is also improved. This report summarizes status and results.
Dose Monitoring in Radiology Departments: Status Quo and Future Perspectives.
Boos, J; Meineke, A; Bethge, O T; Antoch, G; Kröpil, P
2016-05-01
The number of computed tomography examinations has continuously increased over the last decades and accounts for a major part of the collective radiation dose from medical investigations. For purposes of quality assurance in modern radiology a systematic monitoring and analysis of dose related data from radiological examinations is mandatory. Various ways of collecting dose data are available today, for example the Digital Imaging and Communication in Medicine - Structured Report (DICOM-SR), optical character recognition and DICOM-modality performed procedure steps (MPPS). The DICOM-SR is part of the DICOM-standard and provides the DICOM-Radiation Dose Structured Report, which is an easily applicable and comprehensive solution to collect radiation dose parameters. This standard simplifies the process of data collection and enables comprehensive dose monitoring. Various commercial dose monitoring software devices with varying characteristics are available today. In this article, we discuss legal obligations, various ways to monitor dose data, current dose monitoring software solutions and future perspectives in regard to the EU Council Directive 2013/59/EURATOM. • Automated, systematic dose monitoring is an important element in quality assurance of radiology departments. • DICOM-RDSR-capable CT scanners facilitate the monitoring of dose data. • A variety of commercial and non-commercial dose monitoring software tools are available today. • Successful dose monitoring requires comprehensive infrastructure for monitoring, analysing and optimizing radiation exposure. Citation Format: • Boos J, Meineke A, Bethge OT et al. Dose Monitoring in Radiology Departments: Status Quo and Future Perspectives. Fortschr Röntgenstr 2016; 188: 443 - 450. © Georg Thieme Verlag KG Stuttgart · New York.
UV-B Radiation Induces Root Bending Through the Flavonoid-Mediated Auxin Pathway in Arabidopsis.
Wan, Jinpeng; Zhang, Ping; Wang, Ruling; Sun, Liangliang; Wang, Wenying; Zhou, Huakun; Xu, Jin
2018-01-01
Ultraviolet (UV)-B radiation-induced root bending has been reported; however, the underlying mechanisms largely remain unclear. Here, we investigate whether and how auxin and flavonoids are involved in UV-B radiation-induced root bending in Arabidopsis using physiological, pharmacological, and genetic approaches. UV-B radiation modulated the direction of root growth by decreasing IAA biosynthesis and affecting auxin distribution in the root tips, where reduced auxin accumulation and asymmetric auxin distribution were observed. UV-B radiation increased the distribution of auxin on the nonradiated side of the root tips, promoting growth and causing root bending. Further analysis indicated that UV-B induced an asymmetric accumulation of flavonoids; this pathway is involved in modulating the accumulation and asymmetric distribution of auxin in root tips and the subsequent redirection of root growth by altering the distribution of auxin carriers in response to UV-B radiation. Taken together, our results indicate that UV-B radiation-induced root bending occurred through a flavonoid-mediated phototropic response to UV-B radiation.
UV-B Radiation Induces Root Bending Through the Flavonoid-Mediated Auxin Pathway in Arabidopsis
Wan, Jinpeng; Zhang, Ping; Wang, Ruling; Sun, Liangliang; Wang, Wenying; Zhou, Huakun; Xu, Jin
2018-01-01
Ultraviolet (UV)-B radiation-induced root bending has been reported; however, the underlying mechanisms largely remain unclear. Here, we investigate whether and how auxin and flavonoids are involved in UV-B radiation-induced root bending in Arabidopsis using physiological, pharmacological, and genetic approaches. UV-B radiation modulated the direction of root growth by decreasing IAA biosynthesis and affecting auxin distribution in the root tips, where reduced auxin accumulation and asymmetric auxin distribution were observed. UV-B radiation increased the distribution of auxin on the nonradiated side of the root tips, promoting growth and causing root bending. Further analysis indicated that UV-B induced an asymmetric accumulation of flavonoids; this pathway is involved in modulating the accumulation and asymmetric distribution of auxin in root tips and the subsequent redirection of root growth by altering the distribution of auxin carriers in response to UV-B radiation. Taken together, our results indicate that UV-B radiation-induced root bending occurred through a flavonoid-mediated phototropic response to UV-B radiation. PMID:29868074
Rocky Flats Plant Site Environmental Report for 1992
DOE Office of Scientific and Technical Information (OSTI.GOV)
Cirrincione, D.A.; Erdmann, N.L.
1992-12-31
The Rocky Rats Plant Site Environmental Report provides summary information on the plant`s environmental monitoring programs and the results recorded during 1992. The report contains a compliance summary, results of environmental monitoring and other related programs, a review of environmental remediation activities, information on external gamma radiation dose monitoring, and radiation dose estimates for the surrounding population.
Characterization of a quantum cascade laser-based emissivity monitor for CORSAIR
NASA Astrophysics Data System (ADS)
Lwin, Maung; Wojcik, Michael; Latvakoski, Harri; Scott, Deron; Watson, Mike; Marchant, Alan; Topham, Shane; Mlynczak, Martin
2011-06-01
Continuous improvements of quantum cascade laser (QCL) technology have extended the applications in environmental trace gas monitoring, mid-infrared spectroscopy in medicine and life science, law enforcement and homeland security and satellite sensor systems. We present the QCL based emissivity monitor for the CORSAIR blackbody. The emissivity of the blackbody was designed to be better than 0.9999 for the spectral range between 5 to 50μm. To actively monitor changes in blackbody emissivity we employ a QCL-based infrared illumination source. The illumination source consisted of a QCL and thermoelectric cooler (TEC) unit mounted on a copper fixture. The stability of the QCL was measured for 30, 60, and 90s operation time at 1.5A driving current. The temperature distribution along the laser mounting fixture and time dependent system heat dispersion were analyzed. The results were compared to radiative and conductive heat transfer models to define the potential laser operating time and required waiting time to return to initial temperature of the laser mount. The observed cooling behaviour is consistent with a primarily conductive heat transfer mechanism.
In situ measurement of plasma and shock wave properties inside laser-drilled metal holes
NASA Astrophysics Data System (ADS)
Brajdic, Mihael; Hermans, Martin; Horn, Alexander; Kelbassa, Ingomar
2008-10-01
High-speed imaging of shock wave and plasma dynamics is a commonly used diagnostic method for monitoring processes during laser material treatment. It is used for processes such as laser ablation, cutting, keyhole welding and drilling. Diagnosis of laser drilling is typically adopted above the material surface because lateral process monitoring with optical diagnostic methods inside the laser-drilled hole is not possible due to the hole walls. A novel method is presented to investigate plasma and shock wave properties during the laser drilling inside a confined environment such as a laser-drilled hole. With a novel sample preparation and the use of high-speed imaging combined with spectroscopy, a time and spatial resolved monitoring of plasma and shock wave dynamics is realized. Optical emission of plasma and shock waves during drilling of stainless steel with ns-pulsed laser radiation is monitored and analysed. Spatial distributions and velocities of shock waves and of plasma are determined inside the holes. Spectroscopy is accomplished during the expansion of the plasma inside the drilled hole allowing for the determination of electron densities.
Small Active Radiation Monitor
NASA Technical Reports Server (NTRS)
Badhwar, Gautam D.
2004-01-01
A device, named small active radiation monitor, allows on-orbit evaluations during periods of increased radiation, after extravehicular activities, or at predesignated times for crews on such long-duration space missions as on the International Space Station. It also permits direct evaluation of biological doses, a task now performed using a combination of measurements and potentially inaccurate simulations. Indeed the new monitor can measure a full array of radiation levels, from soft x-rays to hard galactic cosmic-ray particles. With refinement, it will benefit commercial (nuclear power-plant workers, airline pilots, medical technicians, physicians/dentists, and others) and military personnel as well as the astronauts for whom thermoluminescent dosimeters are inadequate. Civilian and military personnel have long since graduated from film badges to thermoluminescent dosimeters. Once used, most dosimeters must be returned to a central facility for processing, a step that can take days or even weeks. While this suffices for radiation workers for whom exposure levels are typically very low and of brief duration, it does not work for astronauts. Even in emergencies and using express mail, the results can often be delayed by as much as 24 hours. Electronic dosimeters, which are the size of electronic oral thermometers, and tattlers, small electronic dosimeters that sound an alarm when the dose/dose rate exceeds preset values, are also used but suffer disadvantages similar to those of thermoluminescent dosimeters. None of these devices fully answers the need of rapid monitoring during the space missions. Instead, radiation is monitored by passive detectors, which are read out after the missions. Unfortunately, these detectors measure only the absorbed dose and not the biologically relevant dose equivalent. The new monitor provides a real-time readout, a time history of radiation exposures (both absorbed dose and biologically relevant dose equivalent), and a count of the number of particles passing through a unit area. Better still, the monitor can be used anywhere.
RadWorks Project. ISS REM - to - BIRD - to - HERA: The Evolution of a Technology
NASA Technical Reports Server (NTRS)
McLeod, Catherine D.
2015-01-01
The advancement of particle detectors based on technologies developed for use in high-energy physics applications has enabled the development of a completely new generation of compact low-power active dosimeters and area monitors for use in space radiation environments. One such device, the TimePix, is being developed at CERN, and is providing the technology basis for the most recent line of radiation detection devices being developed by the NASA AES RadWorks project. The most fundamental of these devices, an ISS-Radiation Environment Monitor (REM), is installed as a USB device on ISS where it is monitoring the radiation environment on a perpetual basis. The second generation of this TimePix technology, the BIRD (Battery-operated Independent Radiation Detector), was flown on the NASA EFT-1 flight in December 2014. Data collected by BIRD was the first data made available from the Trapped Belt region of the Earth's atmosphere in over 40 years. The 3rdgeneration of this technology, the HERA (Hybrid Electronic Radiation Assessor), is planned to be integrated into the Orion EM-1, and EM-2 vehicles where it will monitor the radiation environment. For the EM-2 flight, HERA will provide Caution and Warning notification for SPEs as well as real time dose measurements for crew members. The development of this line of radiation detectors provide much greater information and characterization of charged particles in the space radiation environment than has been collected in the past, and in the process provide greater information to inform crew members of radiation related risks, while being very power and mass efficient.
Monitoring, Analyzing and Assessing Radiation Belt Loss and Energization
NASA Astrophysics Data System (ADS)
Daglis, I.; Balasis, G.; Bourdarie, S.; Horne, R.; Khotyaintsev, Y.; Mann, I.; Santolik, O.; Turner, D.; Anastasiadis, A.; Georgiou, M.; Giannakis, O.; Papadimitriou, C.; Ropokis, G.; Sandberg, I.; Angelopoulos, V.; Glauert, S.; Grison, B., Kersten T.; Kolmasova, I.; Lazaro, D.; Mella, M.; Ozeke, L.; Usanova, M.
2013-09-01
We present the concept, objectives and expected impact of the MAARBLE (Monitoring, Analyzing and Assessing Radiation Belt Loss and Energization) project, which is being implemented by a consortium of seven institutions (five European, one Canadian and one US) with support from the European Community's Seventh Framework Programme. The MAARBLE project employs multi-spacecraft monitoring of the geospace environment, complemented by ground-based monitoring, in order to analyze and assess the physical mechanisms leading to radiation belt particle energization and loss. Particular attention is paid to the role of ULF/VLF waves. A database containing properties of the waves is being created and will be made available to the scientific community. Based on the wave database, a statistical model of the wave activity dependent on the level of geomagnetic activity, solar wind forcing, and magnetospheric region will be developed. Multi-spacecraft particle measurements will be incorporated into data assimilation tools, leading to new understanding of the causal relationships between ULF/VLF waves and radiation belt dynamics. Data assimilation techniques have been proven as a valuable tool in the field of radiation belts, able to guide 'the best' estimate of the state of a complex system. The MAARBLE (Monitoring, Analyzing and Assessing Radiation Belt Energization and Loss) collaborative research project has received funding from the European Union’s Seventh Framework Programme (FP7-SPACE-2011-1) under grant agreement no. 284520.
NASA Astrophysics Data System (ADS)
Kaneko, D.; Sakuma, H.
2014-12-01
The first author has been developing RSEM crop-monitoring system using satellite-based assessment of photosynthesis, incorporating meteorological conditions. Crop production comprises of several stages and plural mechanisms based on leaf photosynthesis, surface energy balance, and the maturing of grains after fixation of CO2, along with water exchange through soil vegetation-atmosphere transfer. Grain production in prime countries appears to be randomly perturbed regionally and globally. Weather for crop plants reflects turbulent phenomena of convective and advection flows in atmosphere and surface boundary layer. It has been difficult for scientists to simulate and forecast weather correctly for sufficiently long terms to crop harvesting. However, severely poor harvests related to continental events must originate from a consistent mechanism of abnormal energetic flow in the atmosphere through both land and oceans. It should be remembered that oceans have more than 100 times of energy storage compared to atmosphere and ocean currents represent gigantic energy flows, strongly affecting climate. Anomalies of Sea Surface Temperature (SST), globally known as El Niño, Indian Ocean dipole, and Atlantic Niño etc., affect the seasonal climate on a continental scale. The authors aim to combine monitoring and seasonal forecasting, considering such mechanisms through land-ocean biosphere transfer. The present system produces assessments for all continents, specifically monitoring agricultural fields of main crops. Historical regions of poor and good harvests are compared with distributions of SST anomalies, which are provided by NASA GSFC. Those comparisons fairly suggest that the Worst harvest in 1993 and the Best in 1994 relate to the offshore distribution of low temperature anomalies and high gaps in ocean surface temperatures. However, high-temperature anomalies supported good harvests because of sufficient solar radiation for photosynthesis, and poor harvests because of insufficient precipitation. Integrated rates of photosynthesis on prime grains with planted areas were compared with the SST anomalies in poor and good harvests years. Other factors for poor harvest such as rainfall, solar radiation in addition to the intensity of winds as a measure of pressure perturbations need to be studied.
SORCE: Solar Radiation and Climate Experiment
NASA Technical Reports Server (NTRS)
Cahalan, Robert; Rottman, Gary; Lau, William K. M. (Technical Monitor)
2002-01-01
Contents include the following: Understanding the Sun's influence on the Earth; How the Sun affect Earth's climate; By how much does the Sun's radiation very; Understanding Solar irradiance; History of Solar irradiance observations; The SORCE mission; How do the SORCE instruments measure solar radiation; Total irradiance monitor (TIM); Spectral irradiance monitor (SIM); Solar stellar irradiance comparison experiment (SOLSTICE); XUV photometer system (XPS).
Dazeley, Steven A; Svoboda, Robert C; Bernstein, Adam; Bowden, Nathaniel
2013-02-12
A water Cerenkov-based neutron and high energy gamma ray detector and radiation portal monitoring system using water doped with a Gadolinium (Gd)-based compound as the Cerenkov radiator. An optically opaque enclosure is provided surrounding a detection chamber filled with the Cerenkov radiator, and photomultipliers are optically connected to the detect Cerenkov radiation generated by the Cerenkov radiator from incident high energy gamma rays or gamma rays induced by neutron capture on the Gd of incident neutrons from a fission source. The PMT signals are then used to determine time correlations indicative of neutron multiplicity events characteristic of a fission source.
Radiation Monitoring Equipment Dosimeter Experiment
NASA Technical Reports Server (NTRS)
Hardy, Kenneth A.; Golightly, Michael J.; Quam, William
1992-01-01
Spacecraft crews risk exposure to relatively high levels of ionizing radiation. This radiation may come from charged particles trapped in the Earth's magnetic fields, charged particles released by solar flare activity, galactic cosmic radiation, energetic photons and neutrons generated by interaction of these primary radiations with spacecraft and crew, and man-made sources (e.g., nuclear power generators). As missions are directed to higher radiation level orbits, viz., higher altitudes and inclinations, longer durations, and increased flight frequency, radiation exposure could well become a major factor for crew stay time and career lengths. To more accurately define the radiological exposure and risk to the crew, real-time radiation monitoring instrumentation, which is capable of identifying and measuring the various radiation components, must be flown. This presentation describes a radiation dosimeter instrument which was successfully flown on the Space Shuttle, the RME-3.
Occupational exposure assessment: Practices in Malaysian nuclear agency
DOE Office of Scientific and Technical Information (OSTI.GOV)
Sarowi, S. Muhd, E-mail: suzie@nuclearmalaysia.gov.my; Ramli, S. A.; Kontol, K. Mohamad
Malaysian Nuclear Agency (Nuclear Malaysia) is the leading agency in introducing and promoting the application of nuclear science technology in Malaysia. The agency provides major nuclear facilities purposely for research and commercialisation such as reactor, irradiation plants and radioisotope production laboratory. When dealing with ionizing radiation, there is an obligatory requirement to monitor and assess the radiation exposure to the workers. The personal dose of radiation workers were monitored monthly by assessing their Thermoluminescence Dosimeter (TLD) dose reading. This paper will discuss the current practice in managing, assessing, record keeping and reporting of the occupational exposure in Nuclear Malaysia includingmore » the Health Physic Group roles and challenges. The statistics on occupational radiation exposure of monitored workers working in different fields in Nuclear Malaysia from 2011 - 2013 will also be presented. The results show that the null hypothesis (H{sub 0}) was accepted which the means of every populations are all equal or not differ significantly. This hypothesis states that the dose exposure received by the radiation workers in Nuclear Malaysia is similar and there were no significant changes from 2011 to 2013. The radiation monitoring programme correlate with the requirement of our national law, the Atomic Energy Licensing Act 1984 (Act 304)« less
Occupational exposure assessment: Practices in Malaysian nuclear agency
NASA Astrophysics Data System (ADS)
Sarowi, S. Muhd; Ramli, S. A.; Kontol, K. Mohamad; Rahman, N. A. H. Abd.
2016-01-01
Malaysian Nuclear Agency (Nuclear Malaysia) is the leading agency in introducing and promoting the application of nuclear science technology in Malaysia. The agency provides major nuclear facilities purposely for research and commercialisation such as reactor, irradiation plants and radioisotope production laboratory. When dealing with ionizing radiation, there is an obligatory requirement to monitor and assess the radiation exposure to the workers. The personal dose of radiation workers were monitored monthly by assessing their Thermoluminescence Dosimeter (TLD) dose reading. This paper will discuss the current practice in managing, assessing, record keeping and reporting of the occupational exposure in Nuclear Malaysia including the Health Physic Group roles and challenges. The statistics on occupational radiation exposure of monitored workers working in different fields in Nuclear Malaysia from 2011 - 2013 will also be presented. The results show that the null hypothesis (H₀) was accepted which the means of every populations are all equal or not differ significantly. This hypothesis states that the dose exposure received by the radiation workers in Nuclear Malaysia is similar and there were no significant changes from 2011 to 2013. The radiation monitoring programme correlate with the requirement of our national law, the Atomic Energy Licensing Act 1984 (Act 304).
RadNet Air Data From Honolulu, HI
This page presents radiation air monitoring and air filter analysis data for Honolulu, HI from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
RadNet Air Data From Birmingham, AL
This page presents radiation air monitoring and air filter analysis data for Birmingham, AL from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
RadNet Air Data From Dallas, TX
This page presents radiation air monitoring and air filter analysis data for Dallas, TX from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
RadNet Air Data From Omaha, NE
This page presents radiation air monitoring and air filter analysis data for Omaha, NE from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
RadNet Air Data From Montgomery, AL
This page presents radiation air monitoring and air filter analysis data for Montgomery, AL from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
RadNet Air Data From Burlington, VT
This page presents radiation air monitoring and air filter analysis data for Burlington, VT from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
RadNet Air Data From Washington, DC
This page presents radiation air monitoring and air filter analysis data for Washington, DC from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
RadNet Air Data From Rochester, NY
This page presents radiation air monitoring and air filter analysis data for Rochester, NY from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
RadNet Air Data From Tampa, FL
This page presents radiation air monitoring and air filter analysis data for Tampa, FL from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
RadNet Air Data From Cincinnati, OH
This page presents radiation air monitoring and air filter analysis data for Cincinnati, OH from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
RadNet Air Data From Fairbanks, AK
This page presents radiation air monitoring and air filter analysis data for Fairbanks, AL from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
This page presents radiation air monitoring and air filter analysis data for Yuma, AZ from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
RadNet Air Data From Kalispell, MT
This page presents radiation air monitoring and air filter analysis data for Kalispell, MT from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
RadNet Air Data From Kearney, NE
This page presents radiation air monitoring and air filter analysis data for Kearney, NE from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
RadNet Air Data From Phoenix, AZ
This page presents radiation air monitoring and air filter analysis data for Phoenix, AZ from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
RadNet Air Data From Pierre, SD
This page presents radiation air monitoring and air filter analysis data for Pierre, SD from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
RadNet Air Data From Augusta, GA
This page presents radiation air monitoring and air filter analysis data for Augusta, GA from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
RadNet Air Data From Syracuse, NY
This page presents radiation air monitoring and air filter analysis data for Syracuse, NY from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
RadNet Air Data From Albany, NY
This page presents radiation air monitoring and air filter analysis data for Albany, NY from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
RadNet Air Data From Anchorage, AK
This page presents radiation air monitoring and air filter analysis data for Anchorage, AK from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
RadNet Air Data From Philadelphia, PA
This page presents radiation air monitoring and air filter analysis data for Philadelphia, PA from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
RadNet Air Data From Houston, TX
This page presents radiation air monitoring and air filter analysis data for Houston, TX from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
RadNet Air Data From Duluth, MN
This page presents radiation air monitoring and air filter analysis data for Duluth, MN from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
RadNet Air Data From Raleigh, NC
This page presents radiation air monitoring and air filter analysis data for Raleigh, NC from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
RadNet Air Data From Louisville, KY
This page presents radiation air monitoring and air filter analysis data for Louisville, KY from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
RadNet Air Data From Cleveland, OH
This page presents radiation air monitoring and air filter analysis data for Cleveland, OH from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
RadNet Air Data From Carlsbad, NM
This page presents radiation air monitoring and air filter analysis data for Carlsbad, NM from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
RadNet Air Data From Corvallis, OR
This page presents radiation air monitoring and air filter analysis data for Corvallis, OR from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
RadNet Air Data From Orono, ME
This page presents radiation air monitoring and air filter analysis data for Orono, ME from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
This page presents radiation air monitoring and air filter analysis data for Reno, NV from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
RadNet Air Data From Nashville, TN
This page presents radiation air monitoring and air filter analysis data for Nashville, TN from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
RadNet Air Data From Concord, NH
This page presents radiation air monitoring and air filter analysis data for Concord, NH from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
RadNet Air Data From Paducah, KY
This page presents radiation air monitoring and air filter analysis data for Paducah, KY from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
RadNet Air Data From Edison, NJ
This page presents radiation air monitoring and air filter analysis data for Edison, NJ from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
RadNet Air Data From Wilmington, NC
This page presents radiation air monitoring and air filter analysis data for Wilmington, NC from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
RadNet Air Data From Boise, ID
This page presents radiation air monitoring and air filter analysis data for Boise, ID from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
RadNet Air Data From Albuquerque, NM
This page presents radiation air monitoring and air filter analysis data for Albuquerque, NM from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
RadNet Air Data From Fresno, CA
This page presents radiation air monitoring and air filter analysis data for Fresno, CA from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
RadNet Air Data From Amarillo, TX
This page presents radiation air monitoring and air filter analysis data for Amarillo, TX from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
RadNet Air Data From Portland, OR
This page presents radiation air monitoring and air filter analysis data for Portland, OR from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
RadNet Air Data From Jacksonville, FL
This page presents radiation air monitoring and air filter analysis data for Jacksonville, FL from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
RadNet Air Data From Dover, DE
This page presents radiation air monitoring and air filter analysis data for Dover, DE from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
RadNet Air Data From Baltimore, MD
This page presents radiation air monitoring and air filter analysis data for Baltimore, MD from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
RadNet Air Data From Miami, FL
This page presents radiation air monitoring and air filter analysis data for Miami, FL from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
RadNet Air Data From Billings, MT
This page presents radiation air monitoring and air filter analysis data for Billings, MT from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
RadNet Air Data From Providence, RI
This page presents radiation air monitoring and air filter analysis data for Providence, RI from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
RadNet Air Data From Knoxville, TN
This page presents radiation air monitoring and air filter analysis data for Knoxville, TN from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
RadNet Air Data From Columbus, OH
This page presents radiation air monitoring and air filter analysis data for Columbus, OH from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
RadNet Air Data From Bloomsburg, PA
This page presents radiation air monitoring and air filter analysis data for Bloomsburg, PA from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
RadNet Air Data From Shreveport, LA
This page presents radiation air monitoring and air filter analysis data for Shreveport, LA from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
RadNet Air Data From Laredo, TX
This page presents radiation air monitoring and air filter analysis data for Laredo, TX from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
RadNet Air Data From Bakersfield, CA
This page presents radiation air monitoring and air filter analysis data for Bakersfield, CA from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
RadNet Air Data From Portland, ME
This page presents radiation air monitoring and air filter analysis data for Portland, ME from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
RadNet Air Data From Champaign, IL
This page presents radiation air monitoring and air filter analysis data for Champaign, IL from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
RadNet Air Data From Tucson, AZ
This page presents radiation air monitoring and air filter analysis data for Tucson, AZ from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
RadNet Air Data From Juneau, AK
This page presents radiation air monitoring and air filter analysis data for Juneau, AK from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
RadNet Air Data From Toledo, OH
This page presents radiation air monitoring and air filter analysis data for Toledo, OH from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
RadNet Air Data From Boston, MA
This page presents radiation air monitoring and air filter analysis data for Boston, MA from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
RadNet Air Data From Indianapolis, IN
This page presents radiation air monitoring and air filter analysis data for Indianapolis, IN from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
RadNet Air Data From Yaphank, NY
This page presents radiation air monitoring and air filter analysis data for Yaphank, NY from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
RadNet Air Data From Anaheim, CA
This page presents radiation air monitoring and air filter analysis data for Anaheim, CA from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
RadNet Air Data From Riverside, CA
This page presents radiation air monitoring and air filter analysis data for Riverside, CA from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
RadNet Air Data From Detroit, MI
This page presents radiation air monitoring and air filter analysis data for Detroit, MI from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
RadNet Air Data From Wichita, KS
This page presents radiation air monitoring and air filter analysis data for Wichita, KS from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
RadNet Air Data From Columbia, SC
This page presents radiation air monitoring and air filter analysis data for Columbia, SC from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
RadNet Air Data From Milwaukee, WI
This page presents radiation air monitoring and air filter analysis data for Milwaukee, WI from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
RadNet Air Data From Richmond, VA
This page presents radiation air monitoring and air filter analysis data for Richmond, VA from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
RadNet Air Data From Tulsa, OK
This page presents radiation air monitoring and air filter analysis data for Tulsa, OK from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
RadNet Air Data From Aurora, IL
This page presents radiation air monitoring and air filter analysis data for Aurora, IL from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
RadNet Air Data From Hartford, CT
This page presents radiation air monitoring and air filter analysis data for Hartford. CT from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
RadNet Air Data From Charleston, WV
This page presents radiation air monitoring and air filter analysis data for Charleston, WV from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
RadNet Air Data From Shawano, WI
This page presents radiation air monitoring and air filter analysis data for Shawano, WI from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
RadNet Air Data From Harlingen, TX
This page presents radiation air monitoring and air filter analysis data for Harlingen, TX from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation
RadNet Air Data From Springfield, MO
This page presents radiation air monitoring and air filter analysis data for Springfield, MO from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
RadNet Air Data From Olympia, WA
This page presents radiation air monitoring and air filter analysis data for Olympia, WA from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
RadNet Air Data From Memphis, TN
This page presents radiation air monitoring and air filter analysis data for Memphis, TN from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
RadNet Air Data From Lubbock, TX
This page presents radiation air monitoring and air filter analysis data for Lubbock, TX from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
RadNet Air Data From Sacramento, CA
This page presents radiation air monitoring and air filter analysis data for Sacramento, CA from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
RadNet Air Data From Lockport, NY
This page presents radiation air monitoring and air filter analysis data for Lockport, NY from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
RadNet Air Data From Jackson, MS
This page presents radiation air monitoring and air filter analysis data for Jackson, MS from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
RadNet Air Data From Seattle, WA
This page presents radiation air monitoring and air filter analysis data for Seattle, WA from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
RadNet Air Data From Pittsburgh, PA
This page presents radiation air monitoring and air filter analysis data for Pittsburgh, PA from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
RadNet Air Data From Madison, WI
This page presents radiation air monitoring and air filter analysis data for Madison, WI from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
RadNet Air Data From Ellensburg, WA
This page presents radiation air monitoring and air filter analysis data for Ellensburg, WA from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
RadNet Air Data From Harrisonburg, VA
This page presents radiation air monitoring and air filter analysis data for Harrisonburg, VA from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
RadNet Air Data From Bismarck, ND
This page presents radiation air monitoring and air filter analysis data for Bismarck, ND from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
RadNet Air Data From Denver, CO
This page presents radiation air monitoring and air filter analysis data for Denver, CO from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
RadNet Air Data From Charlotte, NC
This page presents radiation air monitoring and air filter analysis data for Charlotte, NC from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
RadNet Air Data From Lexington, KY
This page presents radiation air monitoring and air filter analysis data for Lexington, KY from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
RadNet Air Data From Casper, WY
This page presents radiation air monitoring and air filter analysis data for Casper, WY from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
RadNet Air Data From Eureka, CA
This page presents radiation air monitoring and air filter analysis data for Eureka, CA from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
RadNet Air Data From Lincoln, NE
This page presents radiation air monitoring and air filter analysis data for Lincoln, NE from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
RadNet Air Data From Orlando, FL
This page presents radiation air monitoring and air filter analysis data for Orlando, FL from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
RadNet Air Data From Mobile, AL
This page presents radiation air monitoring and air filter analysis data for Mobile, AL from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
RadNet Air Data From Spokane, WA
This page presents radiation air monitoring and air filter analysis data for Spokane, WA from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
RadNet Air Data From Atlanta, GA
This page presents radiation air monitoring and air filter analysis data for Atlanta, GA from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
RadNet Air Data From Greensboro, NC
This page presents radiation air monitoring and air filter analysis data for Greensboro, NC from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
RadNet Air Data From Chicago, IL
This page presents radiation air monitoring and air filter analysis data for Chicago, IL from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
2012-12-30
View of radiation monitor,Intra-Vehicular Tissue Equivalent Proportional Counter (IV-TEPC),relocated to NOD2 P3,Part Number (P/N): SEG33120960-301,Serial Number (S/N): 1002,in the Node 2. Photo was taken during Expedition 34.
RadNet Air Data From Worcester, MA
This page presents radiation air monitoring and air filter analysis data for Worcester, MA from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
RadNet Air Data From Austin, TX
This page presents radiation air monitoring and air filter analysis data for Austin, TX from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
Development of absorbing aerosol index simulator based on TM5-M7
NASA Astrophysics Data System (ADS)
Sun, Jiyunting; van Velthoven, Peter; Veefkind, Pepijn
2017-04-01
Aerosols alter the Earth's radiation budget directly by scattering and absorbing solar and thermal radiation, or indirectly by perturbing clouds formation and lifetime. These mechanisms offset the positive radiative forcing ascribed to greenhouse gases. In particular, absorbing aerosols such as black carbon and dust strongly enhance global warming. To quantify the impact of absorbing aerosol on global radiative forcing is challenging. In spite of wide spatial and temporal coverage space-borne instruments (we will use the Ozone Monitoring Instrument, OMI) are unable to derive complete information on aerosol distribution, composition, etc. The retrieval of aerosol optical properties also partly depends on additional information derived from other measurements or global atmospheric chemistry models. Common quantities of great interest presenting the amount of absorbing aerosol are AAOD (absorbing aerosol optical depth), the extinction due to absorption of aerosols under cloud free conditions; and AAI (absorbing aerosol index), a measure of aerosol absorption more directly derivable from UV band observations than AAOD. When comparing model simulations and satellite observations, resemblance is good in terms of the spatial distribution of both parameters. However, the quantitative discrepancy is considerable, indicating possible underestimates of simulated AAI by a factor of 2 to 3. Our research, hence, has started by evaluating to what extent aerosol models, such as our TM5-M7 model, represent the satellite measurements and by identifying the reasons for discrepancies. As a next step a transparent methodology for the comparison between model simulations and satellite observations is under development in the form of an AAI simulator based on TM5-M7.
Survey of instrumentation for environmental monitoring: major update. Volume 3. Radiation
DOE Office of Scientific and Technical Information (OSTI.GOV)
Not Available
1979-09-01
This is the third volume of a four-volume (seven-part) series, the culmination of a comprehensive survey of instrumentation for environmental monitoring. Consideration is given to instruments and techniques presently in use and to those developed for other purposes but having possible applications to radiation monitoring. The results of the survey are given as descriptions of the physical and operating characteristics of available instruments, critical comparisons among instrumentation methods, and recommendations of promising methodology and development of new instrumentation. Information is also given regarding the pollutants to be monitored, their characteristics and forms, their sources and pathways, their effects on themore » ecosystem, and the means of controlling them through process and regulatory controls. The discussion is presented under sections entitled radiation sources; instrumentation: by type of radiation or instrument type; and, instrumentation for specific radionuclides. (JGB)« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wass, P. J.; Araujo, H.; Sumner, T.
We present the concept, design and testing of the radiation monitor for LISA Pathfinder. Galactic cosmic rays (GCRs) and solar energetic particles (SEPs) will cause charging of the LISA Pathfinder test masses producing unwanted disturbances which could be significant during a large solar eruption. A radiation monitor on board LISA Pathfinder, using silicon PIN diodes as particle detectors, will measure the particle flux responsible for charging. It will also be able to record spectral information to identify solar energetic particle events. The design of the monitor was supported by Monte Carlo simulations which allow detailed predictions of the radiation monitormore » performance. We present these predictions as well as the results of high-energy proton tests carried out at the Paul Scherrer Institute, Switzerland. The tests show good agreement with our simulations and confirm the capability of the radiation monitor to perform well in the space environment, meeting all science requirements.« less
Interactive effects of elevated ozone and UV-B radiation on soil nematode diversity.
Bao, Xuelian; Li, Qi; Hua, Jianfeng; Zhao, Tianhong; Liang, Wenju
2014-01-01
Ultraviolet-B (UV-B) radiation and elevated tropospheric ozone may cause reductions in the productivity and quality of important agricultural crops. However, research regarding their interactive effect is still scarce, especially on the belowground processes. Using the open top chambers experimental setup, we monitored the response of soil nematodes to the elevated O3 and UV-B radiation individually as well as in combination. Our results indicated that elevated O3 and UV-B radiation have impact not only on the belowground biomass of plants, but also on the community structure and functional diversity of soil nematodes. The canonical correspondence analysis suggested that soil pH, shoot biomass and microbial biomass C and N were relevant parameters that influencing soil nematode distribution. The interactive effects of elevated O3 and UV-B radiation was only observed on the abundance of bacterivores. UV-B radiation significantly increased the abundance of total nematodes and bacterivores in comparison with the control at pod-filling stage of soybean. Following elevated O3, nematode diversity index decreased and dominance index increased relative to the control at pod-filling stage of soybean. Nematode functional diversity showed response to the effects of elevated O3 and UV-B radiation at pod-bearing stage. Higher enrichment index and lower structure index in the treatment with both elevated O3 and UV-B radiation indicated a stressed soil condition and degraded soil food web. However, the ratios of nematode trophic groups suggested that the negative effects of elevated O3 on soil food web may be weakened by the UV-B radiations.
3D ultrasound Nakagami imaging for radiation-induced vaginal fibrosis
NASA Astrophysics Data System (ADS)
Yang, Xiaofeng; Rossi, Peter; Shelton, Joseph; Bruner, Debrorah; Tridandapani, Srini; Liu, Tian
2014-03-01
Radiation-induced vaginal fibrosis is a debilitating side-effect affecting up to 80% of women receiving radiotherapy for their gynecological (GYN) malignancies. Despite the significant incidence and severity, little research has been conducted to identify the pathophysiologic changes of vaginal toxicity. In a previous study, we have demonstrated that ultrasound Nakagami shape and PDF parameters can be used to quantify radiation-induced vaginal toxicity. These Nakagami parameters are derived from the statistics of ultrasound backscattered signals to capture the physical properties (e.g., arrangement and distribution) of the biological tissues. In this paper, we propose to expand this Nakagami imaging concept from 2D to 3D to fully characterize radiation-induced changes to the vaginal wall within the radiation treatment field. A pilot study with 5 post-radiotherapy GYN patients was conducted using a clinical ultrasound scanner (6 MHz) with a mechanical stepper. A serial of 2D ultrasound images, with radio-frequency (RF) signals, were acquired at 1 mm step size. The 2D Nakagami shape and PDF parameters were calculated from the RF signal envelope with a sliding window, and then 3D Nakagami parameter images were generated from the parallel 2D images. This imaging method may be useful as we try to monitor radiation-induced vaginal injury, and address vaginal toxicities and sexual dysfunction in women after radiotherapy for GYN malignancies.
NASA Technical Reports Server (NTRS)
Saganti, P. B.; Zapp, E. N.; Wilson, J. W.; Cucinotta, F. A.
2001-01-01
The US Lab module of the International Space Station (ISS) is a primary working area where the crewmembers are expected to spend majority of their time. Because of the directionality of radiation fields caused by the Earth shadow, trapped radiation pitch angle distribution, and inherent variations in the ISS shielding, a model is needed to account for these local variations in the radiation distribution. We present the calculated radiation dose (rem/yr) values for over 3,000 different points in the working area of the Lab module and estimated radiation dose values for over 25,000 different points in the human body for a given ambient radiation environment. These estimated radiation dose values are presented in a three dimensional animated interactive visualization format. Such interactive animated visualization of the radiation distribution can be generated in near real-time to track changes in the radiation environment during the orbit precession of the ISS.
The status and prospective of environmental radiation monitoring stations in Saudi Arabia
DOE Office of Scientific and Technical Information (OSTI.GOV)
Al-Kheliewi, Abdullah S.; Holzheimer, Clous
2014-09-30
The use of nuclear technology requires an environmental monitoring program to ensure the safety of the environment, and to protect people from the hazards of radioactive materials, and nuclear accidents. Nuclear accidents are unique, for they incur effects that surpass international frontiers, and can even have a long lasting impact on Earth. Such was the case of the Chernobyl accident in the Ukraine on April 6, 1986. For that purpose, international and national efforts come together to observe for any nuclear or radioactive accident. Many states, including Saudi Arabia which oversees the operation of the National Radiation, Environmental and Earlymore » Monitoring Stations, The Radiation Monitoring Stations(RMS’s) are currently scattered across 35 cities in the country,. These locations are evaluated based on various technological criteria such as border cities, cities of high population density, wind direction, etc. For new nuclear power plants hovering around, it is strongly recommended to increase the number of radiation monitoring stations to warn against any threat that may arise from a nuclear leak or accident and to improve the performance of the existing RMS’s. SARA (Spectroscopic Monitoring Station for air) should be implemented due to the high sensitivity to artificial radiation, automatic isotope identification, free of maintenance, and fully independent due to solar power supply (incl. battery backup) and wireless communication (GPRS)« less
Niagara Falls Storage Site annual site environmental monitoring report. Calendar year 1985
DOE Office of Scientific and Technical Information (OSTI.GOV)
Not Available
1986-04-01
During 1985, an environmental monitoring program was continued at the Niagara Falls Storage Site (NFSS), a United States Department of Energy (DOE) surplus facility located in Niagara County, New York, presently used for the interim storage of low-level radioactive residues and contaminated soils and rubble. The monitoring program is being conducted by Bechtel National, Inc. Monitoring results show that the NFSS is in compliance with DOE concentration guides and radiation protection standards. Derived Concentration Guides (DCGs) represent the concentrations of radionuclides in air or water that would limit the radiation dose to 100 mrem/yr. The applicable limits have been revisedmore » since the 1984 environmental monitoring report was published. The limits applied in 1984 were based on a radiation protection standard of 500 mrem/yr; the limits applied for the 1985 are based on a standard of 100 mrem/yr. To determine whether the site is in compliance with DOE standards, environmental measurements are expressed as percentages of the applicable DCG, while the calculated doses to the public are expressed as percentages of the applicable radiation protection standard. The monitoring program measured radon gas concentrations in air; uranium and radium concentrations in surface water, groundwater, and sediments; and external gamma dose rates. Environmental samples collected were analyzed to determine compliance with applicable standards. Potential radiation doses to the public were also calculated.« less
NASA Astrophysics Data System (ADS)
Chamma, Emilie; Qiu, Jimmy; Lindvere-Teene, Liis; Blackmore, Kristina M.; Majeed, Safa; Weersink, Robert; Dickie, Colleen I.; Griffin, Anthony M.; Wunder, Jay S.; Ferguson, Peter C.; DaCosta, Ralph S.
2015-07-01
Standard clinical management of extremity soft tissue sarcomas includes surgery with radiation therapy. Wound complications (WCs) arising from treatment may occur due to bacterial infection and tissue breakdown. The ability to detect changes in these parameters during treatment may lead to earlier interventions that mitigate WCs. We describe the use of a new system composed of an autofluorescence imaging device and an optical three-dimensional tracking system to detect and coregister the presence of bacteria with radiation doses. The imaging device visualized erythema using white light and detected bacterial autofluorescence using 405-nm excitation light. Its position was tracked relative to the patient using IR reflective spheres and registration to the computed tomography coordinates. Image coregistration software was developed to spatially overlay radiation treatment plans and dose distributions on the white light and autofluorescence images of the surgical site. We describe the technology, its use in the operating room, and standard operating procedures, as well as demonstrate technical feasibility and safety intraoperatively. This new clinical tool may help identify patients at greater risk of developing WCs and investigate correlations between radiation dose, skin response, and changes in bacterial load as biomarkers associated with WCs.
Measurement of particle directions in low earth orbit with a Timepix
NASA Astrophysics Data System (ADS)
Gohl, St.; Bergmann, B.; Granja, C.; Owens, A.; Pichotka, M.; Polansky, S.; Pospisil, S.
2016-11-01
In Low Earth Orbit (LEO) in space electronic equipment aboard satellites and space crews are exposed to high ionizing radiation levels. To reduce radiation damage and the exposure of astronauts, to improve shielding and to assess dose levels, it is valuable to know the composition of the radiation fields and particle directions. The presented measurements are carried out with the Space Application of Timepix Radiation Monitor (SATRAM). There, a Timepix detector (300 μm thick silicon sensor, pixel pitch 55 μm, 256 × 256 pixels) is attached to the Proba-V, an earth observing satellite of the European Space Agency (ESA). The Timepix detector's capability was used to determine the directions of energetic charged particles and their corresponding stopping powers. Data are continuously taken at an altitude of 820 km on a sun-synchronous orbit. The particles pitch angles with respect to the sensor layer were measured and converted to an Earth Centred Earth Fixed (ECEF) coordinate system. Deviations from an isotropic field are extracted by normalization of the observed angular distributions by a Geant4 Monte Carlo simulation —taking the systematics of the reconstruction algorithm and the pixelation into account.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bogdanov, O.V., E-mail: bov@tpu.ru; Department of Higher Mathematics and Mathematical Physics, Tomsk Polytechnic University, Tomsk, 634050; Kazinski, P.O., E-mail: kpo@phys.tsu.ru
The properties of radiation created by a classical ultrarelativistic scalar charged particle in a constant homogeneous crossed electromagnetic field are described both analytically and numerically with radiation reaction taken into account in the form of the Landau–Lifshitz equation. The total radiation naturally falls into two parts: the radiation formed at the entrance point of a particle into the crossed field (the synchrotron entrance radiation), and the radiation coming from the late-time asymptotics of a particle motion (the de-excited radiation). The synchrotron entrance radiation resembles, although does not coincide with, the ultrarelativistic limit of the synchrotron radiation: its distribution over energiesmore » and angles possesses almost the same properties. The de-excited radiation is soft, not concentrated in the plane of motion of a charged particle, and almost completely circularly polarized. The photon energy delivering the maximum to its spectral angular distribution decreases with increasing the initial energy of a charged particle, while the maximum value of this distribution remains the same at the fixed photon observation angle and entrance angle of a charged particle. The ultraviolet and infrared asymptotics of the total radiation are also described. - Highlights: • Properties of an electron radiation in a crossed electromagnetic field are studied. • Spectral angular distribution of the synchrotron entrance radiation is described. • Spectral angular distribution of the de-excited radiation is described. • De-excited radiation is almost completely circularly polarized. • Photon energy at the maximum of the de-excited radiation decreases with increasing the initial energy of an electron.« less
NASA Astrophysics Data System (ADS)
Berger, Thomas
The radiation environment encountered in space differs in nature from that on earth, consisting mostly of high energetic ions from protons up to iron, resulting in radiation levels far exceeding the ones present on earth for occupational radiation workers. Accurate knowledge of the physical characteristics of the space radiation field in dependence on the solar activity, the orbital parameters and the different shielding configurations of the International Space Station (ISS) is therefore needed. For the investigation of the spatial and temporal distribution of the radiation field inside the European Columbus module the experiment “Dose Distribution Inside the ISS” (DOSIS), under the project and science lead of the German Aerospace Center (DLR), was launched on July 15th 2009 with STS-127 to the ISS. The DOSIS experiment consists of a combination of “Passive Detector Packages” (PDP) distributed at eleven locations inside Columbus for the measurement of the spatial variation of the radiation field and two active Dosimetry Telescopes (DOSTELs) with a Data and Power Unit (DDPU) in a dedicated nomex pouch mounted at a fixed location beneath the European Physiology Module rack (EPM) for the measurement of the temporal variation of the radiation field parameters. The DOSIS experiment suite measured during the lowest solar minimum conditions in the space age from July 2009 to June 2011. In July 2011 the active hardware was transferred to ground for refurbishment and preparation for the follow up DOSIS 3D experiment. The hardware for DOSIS 3D was launched with Soyuz 30S to the ISS on May 15th 2012. The PDPs are replaced with each even number Soyuz flight starting with Soyuz 30S. Data from the active detectors is transferred to ground via the EPM rack which is activated once a month for this action. The presentation will give an overview of the DOSIS and DOSIS 3D experiment and focus on the results from the passive radiation detectors from the DOSIS 3D experiment (2012 - 2014) in comparison to the data of the DOSIS experiment (2009 - 2011). The Polish contribution was supported by the National Science Centre (No DEC-2012/06/M/ST9/00423). The CAU contributions to DOSIS and DOSIS 3D are financially supported by BMWi under Grants 50WB0826, 50WB1026 and 50WB1232.
RadNet Air Data From San Juan, PR
This page presents radiation air monitoring and air filter analysis data for San Juan, PR from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
RadNet Air Data From Grand Rapids, MI
This page presents radiation air monitoring and air filter analysis data for Grand Rapids, MI from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
RadNet Air Data From Corpus Christi, TX
This page presents radiation air monitoring and air filter analysis data for Corpus Christi, TX from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
RadNet Air Data From Little Rock, AR
This page presents radiation air monitoring and air filter analysis data for Little Rock, AR from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
RadNet Air Data From Des Moines, IA
This page presents radiation air monitoring and air filter analysis data for Des Moines, IA from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
RadNet Air Data From Fort Madison, IA
This page presents radiation air monitoring and air filter analysis data for Fort Madison, IA from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
RadNet Air Data From Fort Wayne, IN
This page presents radiation air monitoring and air filter analysis data for Fort Wayne, IN from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
RadNet Air Data From Navajo Lake, NM
This page presents radiation air monitoring and air filter analysis data for Navajo Lake, NM from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
RadNet Air Data From Las Vegas, NV
This page presents radiation air monitoring and air filter analysis data for Las Vegas, NV from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
RadNet Air Data From St. George, UT
This page presents radiation air monitoring and air filter analysis data for St. George, UT from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
RadNet Air Data From Jefferson City, MO
This page presents radiation air monitoring and air filter analysis data for Jefferson City, MO from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
RadNet Air Data From Fort Worth, TX
This page presents radiation air monitoring and air filter analysis data for Fort Worth, TX from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
RadNet Air Data From Kansas City, KS
This page presents radiation air monitoring and air filter analysis data for Kansas City, KS from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
RadNet Air Data From San Angelo, TX
This page presents radiation air monitoring and air filter analysis data for San Angelo, TX from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
RadNet Air Data From San Francisco, CA
This page presents radiation air monitoring and air filter analysis data for San Francisco, CA from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
RadNet Air Data From Oklahoma City, OK
This page presents radiation air monitoring and air filter analysis data for Oklahoma City, OK from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
RadNet Air Data From San Bernardino, CA
This page presents radiation air monitoring and air filter analysis data for San Bernardino, CA from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
RadNet Air Data From Idaho Falls, ID
This page presents radiation air monitoring and air filter analysis data for Idaho Falls, ID from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
RadNet Air Data From Los Angeles, CA
This page presents radiation air monitoring and air filter analysis data for Los Angeles, CA from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
RadNet Air Data From El Paso, TX
This page presents radiation air monitoring and air filter analysis data for El Paso, TX from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
RadNet Air Data From Grand Junction, CO
This page presents radiation air monitoring and air filter analysis data for Grand Junction, CO from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
RadNet Air Data From St. Paul, MN
This page presents radiation air monitoring and air filter analysis data for St. Paul, MN from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
RadNet Air Data From Virginia Beach, VA
This page presents radiation air monitoring and air filter analysis data for Virginia Beach, VA from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
RadNet Air Data From La Crosse, WI
This page presents radiation air monitoring and air filter analysis data for La Crosse, WI from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
RadNet Air Data From San Diego, CA
This page presents radiation air monitoring and air filter analysis data for San Diego, CA from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
RadNet Air Data From San Jose, CA
This page presents radiation air monitoring and air filter analysis data for San Jose, CA from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
RadNet Air Data From San Antonio, TX
This page presents radiation air monitoring and air filter analysis data for San Antonio, TX from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
RadNet Air Data From Rapid City, SD
This page presents radiation air monitoring and air filter analysis data for Rapid City, SD from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
RadNet Air Data From Dodge City, KS
This page presents radiation air monitoring and air filter analysis data for Dodge City, KS from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
RadNet Air Data From Colorado Springs, CO
This page presents radiation air monitoring and air filter analysis data for Colorado Springs, CO from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
RadNet Air Data From St. Louis, MO
This page presents radiation air monitoring and air filter analysis data for St. Louis, MO from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
RadNet Air Data From Bay City, MI
This page presents radiation air monitoring and air filter analysis data for Bay City, MI from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
RadNet Air Data From Mason City, IA
This page presents radiation air monitoring and air filter analysis data for Mason City, IA from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
RadNet Air Data From Fort Smith, AR
This page presents radiation air monitoring and air filter analysis data for Fort Smith, AR from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bogdanov, O. V., E-mail: bov@tpu.ru; Fiks, E. I.; Pivovarov, Yu. L.
2012-09-15
Numerical methods are used to study the dependence of the structure and the width of the angular distribution of Vavilov-Cherenkov radiation with a fixed wavelength in the vicinity of the Cherenkov cone on the radiator parameters (thickness and refractive index), as well as on the parameters of the relativistic heavy ion beam (charge and initial energy). The deceleration of relativistic heavy ions in the radiator, which decreases the velocity of ions, modifies the condition of structural interference of the waves emitted from various segments of the trajectory; as a result, a complex distribution of Vavilov-Cherenkov radiation appears. The main quantitymore » is the stopping power of a thin layer of the radiator (average loss of the ion energy), which is calculated by the Bethe-Bloch formula and using the SRIM code package. A simple formula is obtained to estimate the angular distribution width of Cherenkov radiation (with a fixed wavelength) from relativistic heavy ions taking into account the deceleration in the radiator. The measurement of this width can provide direct information on the charge of the ion that passes through the radiator, which extends the potentialities of Cherenkov detectors. The isotopic effect (dependence of the angular distribution of Vavilov-Cherenkov radiation on the ion mass) is also considered.« less
Variability of daily UV index in Jokioinen, Finland, in 1995-2015
NASA Astrophysics Data System (ADS)
Heikkilä, A.; Uusitalo, K.; Kärhä, P.; Vaskuri, A.; Lakkala, K.; Koskela, T.
2017-02-01
UV Index is a measure for UV radiation harmful for the human skin, developed and used to promote the sun awareness and protection of people. Monitoring programs conducted around the world have produced a number of long-term time series of UV irradiance. One of the longest time series of solar spectral UV irradiance in Europe has been obtained from the continuous measurements of Brewer #107 spectrophotometer in Jokioinen (lat. 60°44'N, lon. 23°30'E), Finland, over the years 1995-2015. We have used descriptive statistics and estimates of cumulative distribution functions, quantiles and probability density functions in the analysis of the time series of daily UV Index maxima. Seasonal differences in the estimated distributions and in the trends of the estimated quantiles are found.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Cho, M; Kim, T; Kang, S
Purpose: The purpose of this work is to develop a new patient set-up monitoring system using force sensing resistor (FSR) sensors that can confirm pressure of contact surface and evaluate its feasibility. Methods: In this study, we focused on develop the patient set-up monitoring system to compensate for the limitation of existing optical based monitoring system, so the developed system can inform motion in the radiation therapy. The set-up monitoring system was designed consisting of sensor units (FSR sensor), signal conditioning devices (USB cable/interface electronics), a control PC, and a developed analysis software. The sensor unit was made by attachingmore » FSR sensor and dispersing pressure sponge to prevent error which is caused by concentrating specific point. Measured signal from the FSR sensor was sampled to arduino mega 2560 microcontroller, transferred to control PC by using serial communication. The measured data went through normalization process. The normalized data was displayed through the developed graphic user interface (GUI) software. The software was designed to display a single sensor unit intensity (maximum 16 sensors) and display 2D pressure distribution (using 16 sensors) according to the purpose. Results: Changes of pressure value according to motion was confirmed by the developed set-up monitoring system. Very small movement such as little physical change in appearance can be confirmed using a single unit and using 2D pressure distribution. Also, the set-up monitoring system can observe in real time. Conclusion: In this study, we developed the new set-up monitoring system using FSR sensor. Especially, we expect that the new set-up monitoring system is suitable for motion monitoring of blind area that is hard to confirm existing optical system and compensate existing optical based monitoring system. As a further study, an integrated system will be constructed through correlation of existing optical monitoring system. This work was supported by the Industrial R&D program of MOTIE/KEIT. [10048997, Development of the core technology for integrated therapy devices based on real-time MRI guided tumor tracking] and the Mid-career Researcher Program (2014R1A2A1A10050270) through the National Research Foundation of Korea funded by the Ministry of Science, ICT&Future Planning.« less
Self-indicating radiation alert dosemeter (SIRAD).
Riel, Gordon K; Winters, Patrick; Patel, Gordhan; Patel, Paresh
2006-01-01
In an event of a nuclear or dirty bomb explosion and a radiological accident, there is a need for self-indicating instant radiation dosemeter for monitoring radiation exposure. The self-indicating instant radiation alert dosemeter (SIRAD) is a credit card size radiation dosemeter for monitoring ionising radiation from a few hundredths of a Gray to a few Gray. It is always active and is ready to use. It needs no battery. The dosemeter develops colour instantly upon exposure, and the colour intensifies with dose. It has a colour chart so that the dose on the active element may be read by matching its colour with the chart that is printed next to it on the card. However, in this work, the dose is measured by the optical density of the element. The dosemeter cannot be reset. The response changes by <1% per degrees C from -20 to +60 degrees C. The shelf-life is >3 y at room temperature. It contains no hazardous materials. The dosemeter would meet the requirements of instantly monitoring high dose in an event of a nuclear or dirty bomb explosion or a radiation accident.
Monitoring of Solar Radiation Intensity using Wireless Sensor Network for Plant Growing
NASA Astrophysics Data System (ADS)
Siregar, B.; Fadli, F.; Andayani, U.; Harahap, LA; Fahmi, F.
2017-01-01
Abstract— Plant growth is highly depending on the sunlight, if the consumption of sunlight is enough, it will grow well. The plant will be green because of its chlorophyll and it can perform photosynthesis at maximum; but if the plants get less sunlight, it will make the plants be yellowing. Radiation is electromagnetic waves that are good for plants, so-called visible light. In the electromagnetic wave spectrum the best wavelength range from 400-700 nm for the plant. A monitoring of sun intensity is needed in order to obtain sufficient solar radiation consumption and provide notification if there is a high radiation. In this study, several sensors and devices were combined such as photosynthetic solar radiation sensors, GSM / GPRS and waspmote as a main board or a microcontroller. The test was carried out on at least three occasions; the system has a stable radiation in the morning with an average of 505.51 micrometers. IN this study, we have successfully developed a monitoring tools for solar radiation intensity applied on plant growth by using wireless sensor network.
Packet personal radiation monitor
Phelps, James E.
1989-01-01
A personal radiation monitor of the chirper type is provided for detecting ionizing radiation. A battery powered high voltage power supply is used to generate and apply a high voltage bias to a G-M tube radiation sensor. The high voltage is monitored by a low-loss sensing network which generates a feedback signal to control the high voltage power supply such that the high voltage bias is recharged to +500 VDC when the current pulses of the sensor, generated by the detection of ionizing radiation events, discharges the high voltage bias to +450 VDC. During the high voltage recharge period an audio transducer is activated to produce an audible "chirp". The rate of the "chirps" is controlled by the rate at which the high voltage bias is recharged, which is proportional to the radiation field intensity to which the sensor is exposed. The chirp rate sensitivity is set to be approximately 1.5 (chirps/min/MR/hr.). The G-M tube sensor is used in a current sensing mode so that the device does not paralyze in a high radiation field.
NASA Astrophysics Data System (ADS)
Ferraro, R.; Danzeca, S.; Brucoli, M.; Masi, A.; Brugger, M.; Dilillo, L.
2017-04-01
The need for upgrading the Total Ionizing Dose (TID) measurement resolution of the current version of the Radiation Monitoring system for the LHC complex has driven the research of new TID sensors. The sensors being developed nowadays can be defined as Systems On Chip (SOC) with both analog and digital circuitries embedded in the same silicon. A radiation tolerant TID Monitoring System (TIDMon) has been designed to allow the placement of the entire dosimeter readout electronics in very harsh environments such as calibration rooms and even in the mixed radiation field such as the one of the LHC complex. The objective of the TIDMon is to measure the effect of the TID on the new prototype of Floating Gate Dosimeter (FGDOS) without using long cables and with a reliable measurement system. This work introduces the architecture of the TIDMon, the radiation tolerance techniques applied on the controlling electronics as well as the design choices adopted for the system. Finally, results of several tests of TIDMon under different radiation environments such as gamma rays or mixed radiation field at CHARM are presented.
RadNet Air Data From Salt Lake City, UT
This page presents radiation air monitoring and air filter analysis data for Salt Lake City, UT from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
RadNet Air Data From New York City, NY
This page presents radiation air monitoring and air filter analysis data for New York City, NY from EPA's RadNet system. RadNet is a nationwide network of monitoring stations that measure radiation in air, drinking water and precipitation.
REVIEW OF THE RADNET AIR MONITORING NETWORK UPGRADE AND EXPANSION
RadNet, formerly known as ERAMS, has been operating since the 1970's, monitoring environmental radiation across the country, supporting responses to radiological emergencies, and providing important information on background levels of radiation in the environment. The original ...
DOE Office of Scientific and Technical Information (OSTI.GOV)
Podonsky, Glenn S.
The U.S. Department of Energy (DOE) Office of Analysis within the Office of Health, Safety and Security (HSS) publishes the annual DOE Occupational Radiation Exposure Report to provide an overview of the status of radiation protection practices at DOE (including the National Nuclear Security Administration [NNSA]). The DOE 2012 Occupational Radiation Exposure Report provides an evaluation of DOE-wide performance regarding compliance with Title 10, Code of Federal Regulations (C.F.R.), Part 835, Occupational Radiation Protection dose limits and as low as reasonably achievable (ALARA) process requirements. In addition, the report provides data to DOE organizations responsible for developing policies for protectionmore » of individuals from the adverse health effects of radiation. The report provides a summary and an analysis of occupational radiation exposure information from the monitoring of individuals involved in DOE activities. Over the past 5-year period, the occupational radiation exposure information is analyzed in terms of aggregate data, dose to individuals, and dose by site. As an indicator of the overall amount of radiation dose received during the conduct of operations at DOE, the report includes information on collective total effective dose (TED). The TED is comprised of the effective dose (ED) from external sources, which includes neutron and photon radiation, and the internal committed effective dose (CED), which results from the intake of radioactive material into the body. The collective ED from photon exposure decreased by 23% between 2011 and 2012, while the neutron dose increased by 5%. The internal dose components of the collective TED decreased by 7%. Over the past 5-year period, 99.99% of the individuals receiving measurable TED have received doses below the 2 roentgen equivalent in man (rems) (20 millisievert [mSv]) TED administrative control level (ACL), which is well below the DOE regulatory limit of 5 rems (50 mSv) TED annually. The occupational radiation exposure records show that in 2012, DOE facilities continued to comply with DOE dose limits and ACLs and worked to minimize exposure to individuals. The DOE collective TED decreased 17.1% from 2011 to 2012. The collective TED decreased at three of the five sites with the largest collective TED. u Idaho Site – Collective dose reductions were achieved as a result of continuing improvements at the Advanced Mixed Waste Treatment Project (AMWTP) through the planning of drum movements that reduced the number of times a container is handled; placement of waste containers that created highradiation areas in a centralized location; and increased worker awareness of high-dose rate areas. In addition, Idaho had the largest decrease in the total number of workers with measurable TED (1,143 fewer workers). u Hanford Site (Hanford) – An overall reduction of decontamination and decommissioning (D&D) activities at the Plutonium Finishing Plant (PFP) and Transuranic (TRU) retrieval activities resulted in collective dose reductions. u Savannah River Site (SRS) – Reductions were achieved through ALARA initiatives employed site wide. The Solid Waste Management Facility used extended specialty tools, cameras and lead shield walls to facilitate removal of drums. These tools and techniques reduce exposure time through improved efficiency, increase distance from the source of radiation by remote monitoring, shield the workers to lower the dose rate, and reduce the potential for contamination and release of material through repacking of waste. Overall, from 2011 to 2012, there was a 19% decrease in the number of workers with measurable dose. Furthermore, due to a slight decrease in both the DOE workforce (7%) and monitored workers (10%), the ratio of workers with measurable doses to monitored workers decreased to 13%. Another primary indicator of the level of radiation exposure covered in this report is the average measurable dose, which normalizes the collective dose over the population of workers who actually received a measurable dose. The average measurable TED increased by 3% from 2011 to 2012. Additional analyses show that the dose distribution in 2012 was similar to the distribution in 2011. In 2012, 13% of the monitored workers received a measurable TED and the average measurable TED, 0.069 rem, was less than 2% of the DOE limit. From 2011 to 2012, the collective TED and the number of individuals with measurable TED decreased 17.1% and 19%, respectively. These decreases were mainly due to an overall reduction of D&D activities at the PFP and TRU retrieval activities at Hanford; a 78% decrease in the number of targeted waste drums that were processed at the Idaho Site’s Accelerated Retrieval Project (ARP) from 5,566 drums in 2011 to a total of 1,211 drums processed in 2012; and ALARA initiatives employed site wide at SRS. In addition, the decreases were the result of decreased American Recovery and Reinvestment Act (ARRA) activities and continuing D&D, particularly at the DOE sites that comprise the majority of DOE collective dose. Over the past 5 years, the size of the monitored workforce has remained at a fairly stable level (within 12%), while the collective dose has varied up to 37%. No reported doses exceeded the DOE occupational limit of 5 rems TED in 2012 and no reported doses exceeded the DOE ACL of 2 rems TED.« less
Annual environmental monitoring report of the Lawrence Berkeley Laboratory
DOE Office of Scientific and Technical Information (OSTI.GOV)
Schleimer, G.E.
1989-06-01
The Environmental Monitoring Program of the Lawrence Berkeley Laboratory (LBL) is described. Data for 1988 are presented and general trends are discussed. In order to establish whether LBL research activities produced any impact on the population surrounding the laboratory, a program of environmental air and water sampling and continuous radiation monitoring was carried on throughout the year. For 1988, as in the previous several years, dose equivalents attributable to LBL radiological operations were a small fraction of both the relevant radiation protection guidelines (RPG) and of the natural radiation background. 16 refs., 7 figs., 21 tabs.
A system for monitoring the radiation effects of a proton linear accelerator
DOE Office of Scientific and Technical Information (OSTI.GOV)
Skorkin, V. M., E-mail: skorkin@inr.ru; Belyanski, K. L.; Skorkin, A. V.
2016-12-15
The system for real-time monitoring of radioactivity of a high-current proton linear accelerator detects secondary neutron emission from proton beam losses in transport channels and measures the activity of radionuclides in gas and aerosol emissions and the radiation background in the environment affected by a linear accelerator. The data provided by gamma, beta, and neutron detectors are transferred over a computer network to the central server. The system allows one to monitor proton beam losses, the activity of gas and aerosol emissions, and the radiation emission level of a linear accelerator in operation.
SCCT guidelines on radiation dose and dose-optimization strategies in cardiovascular CT
Halliburton, Sandra S.; Abbara, Suhny; Chen, Marcus Y.; Gentry, Ralph; Mahesh, Mahadevappa; Raff, Gilbert L.; Shaw, Leslee J.; Hausleiter, Jörg
2012-01-01
Over the last few years, computed tomography (CT) has developed into a standard clinical test for a variety of cardiovascular conditions. The emergence of cardiovascular CT during a period of dramatic increase in radiation exposure to the population from medical procedures and heightened concern about the subsequent potential cancer risk has led to intense scrutiny of the radiation burden of this new technique. This has hastened the development and implementation of dose reduction tools and prompted closer monitoring of patient dose. In an effort to aid the cardiovascular CT community in incorporating patient-centered radiation dose optimization and monitoring strategies into standard practice, the Society of Cardiovascular Computed Tomography has produced a guideline document to review available data and provide recommendations regarding interpretation of radiation dose indices and predictors of risk, appropriate use of scanner acquisition modes and settings, development of algorithms for dose optimization, and establishment of procedures for dose monitoring. PMID:21723512
Bai, Penggang; Du, Min; Ni, Xiaolei; Ke, Dongzhong; Tong, Tong
2017-01-01
The combination external-beam radiotherapy and high-dose-rate brachytherapy is a standard form of treatment for patients with locally advanced uterine cervical cancer. Personalized radiotherapy in cervical cancer requires efficient and accurate dose planning and assessment across these types of treatment. To achieve radiation dose assessment, accurate mapping of the dose distribution from HDR-BT onto EBRT is extremely important. However, few systems can achieve robust dose fusion and determine the accumulated dose distribution during the entire course of treatment. We have therefore developed a toolbox (FZUImageReg), which is a user-friendly dose fusion system based on hybrid image registration for radiation dose assessment in cervical cancer radiotherapy. The main part of the software consists of a collection of medical image registration algorithms and a modular design with a user-friendly interface, which allows users to quickly configure, test, monitor, and compare different registration methods for a specific application. Owing to the large deformation, the direct application of conventional state-of-the-art image registration methods is not sufficient for the accurate alignment of EBRT and HDR-BT images. To solve this problem, a multi-phase non-rigid registration method using local landmark-based free-form deformation is proposed for locally large deformation between EBRT and HDR-BT images, followed by intensity-based free-form deformation. With the transformation, the software also provides a dose mapping function according to the deformation field. The total dose distribution during the entire course of treatment can then be presented. Experimental results clearly show that the proposed system can achieve accurate registration between EBRT and HDR-BT images and provide radiation dose warping and fusion results for dose assessment in cervical cancer radiotherapy in terms of high accuracy and efficiency. PMID:28388623
Sources of Ionizing Radiation in Interplanetary Space
2013-05-30
This illustration depicts the two main types of radiation that NASA Radiation Assessment Detector RAD onboard Curiosity monitors, and how the magnetic field around Earth affects the radiation in space near Earth.
Wilson, Sharon M; Prasan, Ananth M; Virdi, Amy; Lassere, Marissa; Ison, Glenn; Ramsay, David R; Weaver, James C
2016-10-10
The aim of this study was to evaluate whether a real-time (RT) colour pictorial radiation dose monitoring system reduces patient skin and total radiation dose during coronary angiography and intervention. Patient demographics, procedural variables and radiation parameters were recorded before and after institution of the RT skin dose recording system. Peak skin dose as well as traditionally available measures of procedural radiation dose were compared. A total of 1,077 consecutive patients underwent coronary angiography, of whom 460 also had PCI. Institution of the RT skin dose recording system resulted in a 22% reduction in peak skin dose after accounting for confounding variables. Radiation dose reduction was most pronounced in those having PCI but was also seen over a range of subgroups including those with prior coronary artery bypass surgery, high BMI, and with radial arterial access. This was associated with a significant reduction in the number of patients placed at risk of skin damage. Similar reductions in parameters reflective of total radiation dose were also demonstrated after institution of RT radiation monitoring. Institution of an RT skin dose recording reduced patient peak skin and total radiation dose during coronary angiography and intervention. Consideration should be given to widespread adoption of this technology.
Energetic balance in an ultrasonic reactor using focused or flat high frequency transducers.
Hallez, L; Touyeras, F; Hihn, J Y; Klima, J
2007-09-01
In order to undertake irradiation of polymer blocks or films by ultrasound, this paper deals with the measurements of ultrasonic power and its distribution within the cell by several methods. The electric power measured at the transducer input is compared to the ultrasonic power input to the cell evaluated by calorimetry and radiation force measurement for different generator settings. Results obtained in the specific case of new transducer types (composites and focused composites i.e., HIFU: high intensity focused ultrasound) provide an opportunity to conduct a discussion about measurement methods. It has thus been confirmed that these measurement techniques can be applied to HIFU transducers. For all cases, results underlined the fact that measurement of radiation pressure for power evaluation is more adapted to low powers (<15 W) and that measurement by calorimetry is a valid technique for global energy measurements. Composites and monocomponent transducers were compared and it appears that the presence of an adaptation glass plate reduces the efficiency of the monocomponent transducers. The distribution of ultrasonic intensity is qualitatively depicted by sono-chemiluminescence of luminol. Finally, the quantity of energy absorbed by samples placed in the sound field is determined and the temperature distribution monitored as a function of wall distance. This energetic balance allows us to understand the global behaviour of all experimental set-ups made up of a generator-transducer-liquid and sample.
Design of wideband solar ultraviolet radiation intensity monitoring and control system
NASA Astrophysics Data System (ADS)
Ye, Linmao; Wu, Zhigang; Li, Yusheng; Yu, Guohe; Jin, Qi
2009-08-01
According to the principle of SCM (Single Chip Microcomputer) and computer communication technique, the system is composed of chips such as ATML89C51, ADL0809, integrated circuit and sensors for UV radiation, which is designed for monitoring and controlling the UV index. This system can automatically collect the UV index data, analyze and check the history database, research the law of UV radiation in the region.
Method and apparatus for real time imaging and monitoring of radiotherapy beams
Majewski, Stanislaw [Yorktown, VA; Proffitt, James [Newport News, VA; Macey, Daniel J [Birmingham, AL; Weisenberger, Andrew G [Yorktown, VA
2011-11-01
A method and apparatus for real time imaging and monitoring of radiation therapy beams is designed to preferentially distinguish and image low energy radiation from high energy secondary radiation emitted from a target as the result of therapeutic beam deposition. A detector having low sensitivity to high energy photons combined with a collimator designed to dynamically image in the region of the therapeutic beam target is used.
Plan for the Characterization of HIRF Effects on a Fault-Tolerant Computer Communication System
NASA Technical Reports Server (NTRS)
Torres-Pomales, Wilfredo; Malekpour, Mahyar R.; Miner, Paul S.; Koppen, Sandra V.
2008-01-01
This report presents the plan for the characterization of the effects of high intensity radiated fields on a prototype implementation of a fault-tolerant data communication system. Various configurations of the communication system will be tested. The prototype system is implemented using off-the-shelf devices. The system will be tested in a closed-loop configuration with extensive real-time monitoring. This test is intended to generate data suitable for the design of avionics health management systems, as well as redundancy management mechanisms and policies for robust distributed processing architectures.
NASA Astrophysics Data System (ADS)
Kurzeja, Robert J.; O'Steen, Byron L.; Pendergast, Malcolm M.
2002-01-01
The Tropical Pacific Island of Nauru is a US DOE ARM observation site that monitors tropical climate and atmospheric radiation. This observation site is ideal for validating MTI images because of the extensive deployment of continuously operating instruments. MTI images are also useful in assessing the effect of the island on the ocean climate and on the ARM data. An MTI image has been used to determine the spatial distribution of water vapor and sea-surface temperature near the island. The results are compared with a three-dimensional numerical model simulation.
Wilson, Jolaine M.; Sanzari, Jenine K.; Diffenderfer, Eric S.; Yee, Stephanie S.; Seykora, John T.; Maks, Casey; Ware, Jeffrey H.; Litt, Harold I.; Reetz, Jennifer A.; McDonough, James; Weissman, Drew; Kennedy, Ann R.; Cengel, Keith A.
2011-01-01
In a solar particle event (SPE), an unshielded astronaut would receive proton radiation with an energy profile that produces a highly inhomogeneous dose distribution (skin receiving a greater dose than internal organs). The novel concept of using megavoltage electron-beam radiation to more accurately reproduce both the total dose and the dose distribution of SPE protons and make meaningful RBE comparisons between protons and conventional radiation has been described previously. Here, Yucatan minipigs were used to determine the effects of a superficial, SPE-like proton dose distribution using megavoltage electrons. In these experiments, dose-dependent increases in skin pigmentation, ulceration, keratinocyte necrosis and pigment incontinence were observed. Five of 18 animals (one each exposed to 7.5 Gy and 12.5 Gy radiation and three exposed to 25 Gy radiation) developed symptomatic, radiation-associated pneumonopathy approximately 90 days postirradiation. The three animals from the highest dose group showed evidence of mycoplasmal pneumonia along with radiation pneumonitis. Moreover, delayed-type hypersensitivity was found to be altered, suggesting that superficial irradiation of the skin with ionizing radiation might cause immune dysfunction or dysregulation. In conclusion, using total doses, patterns of dose distribution, and dose rates that are compatible with potential astronaut exposure to SPE radiation, animals experienced significant toxicities that were qualitatively different from toxicities previously reported in pigs for homogeneously delivered radiation at similar doses. PMID:21859326
NASA Astrophysics Data System (ADS)
Baeza-Romero, María Teresa; Gaie-Levrel, Francois; Mahjoub, Ahmed; López-Arza, Vicente; Garcia, Gustavo A.; Nahon, Laurent
2016-07-01
A reaction chamber was coupled to a photoionization aerosol time-of-flight mass spectrometer based on an electron/ion coincidence scheme and applied for on-line analysis of organic and inorganic-organic mixed aerosols using synchrotron tunable vacuum ultraviolet (VUV) photons as the ionization source. In this proof of principle study, both aerosol and gas phase were detected simultaneously but could be differentiated. Present results and perspectives for improvement for this set-up are shown in the study of ozonolysis ([O3] = 0.13-3 ppm) of α-pinene (2-3 ppm), and the uptake of glyoxal upon ammonium sulphate. In this work the ozone concentration was monitored in real time, together with the particle size distributions and chemical composition, the latter taking advantage of the coincidence spectrometer and the tuneability of the synchrotron radiation as a soft VUV ionization source.
NASA Astrophysics Data System (ADS)
Abramov, D. V.; Arakelyan, S. M.; Galkin, A. F.; Klimovskii, Ivan I.; Kucherik, A. O.; Prokoshev, V. G.
2006-06-01
The video image of the graphite surface exposed to focused laser radiation is obtained with the help of a laser monitor. A bright ring moving over the heated surface was observed. A method for reconstructing the surface relief from the video image is proposed and realised. The method is based on the measurement of the angular distribution of the light intensity scattered by the graphite sample surface. The surface relief of the graphite sample changing in time is reconstructed. The relative change in the relief height during laser excitation is measured. The statistical characteristics of the reconstructed graphite surface shape and their variation during laser irradiation are studied. It is found that a circular convexity appears within the bright ring. The formation mechanism of this convexity requires further investigations.
Individual Radiation Protection Monitoring in the Marshall Islands: Utrok Atoll (2003-2004)
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hamilton, T F; Kehl, S; Hickman, D
2006-01-17
The United States Department of Energy (U.S. DOE) has recently implemented a series of strategic initiatives to address long-term radiological surveillance needs at former U.S. nuclear test sites in the Marshall Islands. The plan is to engage local atoll communities in developing shared responsibilities for implementing radiation protection monitoring programs for resettled and resettling populations in the northern Marshall Islands. Using the pooled resources of the U.S. DOE and local atoll governments, individual radiological surveillance programs have been developed in whole body counting and plutonium urinalysis in order to accurately assess radiation doses resulting from the ingestion and uptake ofmore » fallout radionuclides contained in locally grown foods. Permanent whole body counting facilities have been established at three separate locations in the Marshall Islands (Figure 1). These facilities are operated and maintained by Marshallese technicians with scientists from the Lawrence Livermore National Laboratory (LLNL) providing on-going technical support services. Bioassay samples are collected under controlled conditions and analyzed for plutonium isotopes at the Center for Accelerator Mass Spectrometry at LLNL using state-of-the art measurement technologies. We also conduct an on-going environmental monitoring and characterization program at selected sites in the northern Marshall Islands. The aim of the environmental program is to determine the level and distribution of important fallout radionuclides in soil, water and local foods with a view towards providing more accurate and updated dose assessments, incorporating knowledge of the unique behaviors and exposure pathways of fallout radionuclides in coral atoll ecosystems. These scientific studies have also been essential in helping guide the development of remedial options used in support of island resettlement. Together, the individual and environmental radiological surveillance programs are helping meet the informational needs of the U.S. DOE and the Republic of the Marshall Islands. Our updated environmental assessments provide a strong scientific basis for predicting future change in exposure conditions especially in relation to changes in life-style, diet and/or land-use patterns. This information has important implications in addressing questions about existing (and future) radiological conditions on the islands, in determining the cost and the effectiveness of potential remedial measures, and in general policy support considerations. Perhaps most importantly, the recently established individual radiological surveillance programs provide affected atoll communities with an unprecedented level of radiation protection monitoring where, for the first time, local resources are being made available to monitor resettled and resettling populations on a continuous basis. As a hard copy supplement to Marshall Islands Program website (http://eed.llnl.gov/mi/), this document provides an overview of the individual radiation surveillance monitoring program established for the Utrok Atoll population group along with a full disclosure of all verified measurement data (2003-2004). The Utrok whole body counting facility has been temporarily stationed on Majuro Atoll and, in cooperation with the Utrok Atoll Local Government, serves as a national facility open to the general public. Readers are advised that an additional feature of the associated website is a provision whereby users are able to calculate and track radiation doses delivered to volunteers (de-identified information only) participating in the Marshall Islands Radiological Surveillance Program.« less
A New Active Space Radiation Instruments for the International Space Station, A-DREAMS
NASA Astrophysics Data System (ADS)
Uchihori, Yukio; Kodaira, Satoshi; Kitamura, Hisashi; Kobayashi, Shingo
For future space experiments in the International Space Station (ISS) or other satellites, radiation detectors, A-DREAMS (Active Dosimeter for Radiation Environment and Astronautic Monitoring in Space), using single or multiple silicon semi-conductor detectors have been developed. The first version of the detectors were produced and calibrated with particle accelerators. National Institute of Radiological Sciences has a medical heavy ion accelerator (HIMAC) for cancer therapy and a cyclotron accelerator. The detector was irradiated with high energy heavy ions and protons in HIMAC and the cyclotron and calibrated the energy resolution and linearity for deposited energies of these particles. We are planned to be going to use the new instrument in an international project, the new MATROSHKA experiment which is directed by members in the Institute of Bio-Medical Problem (IBMP) in Russia and German Space Center (DLR) in Germany. In the project, the dose distribution in human torso phantom will be investigated for several months in the ISS. For the project, a new type of the instruments is under development in NIRS and the current situation will be reported in this paper.
Belle-II VXD radiation monitoring and beam abort with sCVD diamond sensors
NASA Astrophysics Data System (ADS)
Adamczyk, K.; Aihara, H.; Angelini, C.; Aziz, T.; Babu, V.; Bacher, S.; Bahinipati, S.; Barberio, E.; Baroncelli, T.; Basith, A. K.; Batignani, G.; Bauer, A.; Behera, P. K.; Bergauer, T.; Bettarini, S.; Bhuyan, B.; Bilka, T.; Bosi, F.; Bosisio, L.; Bozek, A.; Buchsteiner, F.; Casarosa, G.; Ceccanti, M.; Červenkov, D.; Chendvankar, S. R.; Dash, N.; Divekar, S. T.; Doležal, Z.; Dutta, D.; Forti, F.; Friedl, M.; Hara, K.; Higuchi, T.; Horiguchi, T.; Irmler, C.; Ishikawa, A.; Jeon, H. B.; Joo, C.; Kandra, J.; Kang, K. H.; Kato, E.; Kawasaki, T.; Kodyš, P.; Kohriki, T.; Koike, S.; Kolwalkar, M. M.; Kvasnička, P.; Lanceri, L.; Lettenbicher, J.; Mammini, P.; Mayekar, S. N.; Mohanty, G. B.; Mohanty, S.; Morii, T.; Nakamura, K. R.; Natkaniec, Z.; Negishi, K.; Nisar, N. K.; Onuki, Y.; Ostrowicz, W.; Paladino, A.; Paoloni, E.; Park, H.; Pilo, F.; Profeti, A.; Rashevskaya, I.; Rao, K. K.; Rizzo, G.; Rozanska, M.; Sandilya, S.; Sasaki, J.; Sato, N.; Schultschik, S.; Schwanda, C.; Seino, Y.; Shimizu, N.; Stypula, J.; Tanaka, S.; Tanida, K.; Taylor, G. N.; Thalmeier, R.; Thomas, R.; Tsuboyama, T.; Uozumi, S.; Urquijo, P.; Vitale, Lorenzo; Volpi, M.; Watanuki, S.; Watson, I. J.; Webb, J.; Wiechczynski, J.; Williams, S.; Würkner, B.; Yamamoto, H.; Yin, H.; Yoshinobu, T.
2016-07-01
The Belle-II VerteX Detector (VXD) has been designed to improve the performances with respect to Belle and to cope with an unprecedented luminosity of 8 ×1035cm-2s-1 achievable by the SuperKEKB. Special care is needed to monitor both the radiation dose accumulated throughout the life of the experiment and the instantaneous radiation rate, in order to be able to promptly react to sudden spikes for the purpose of protecting the detectors. A radiation monitoring and beam abort system based on single-crystal diamond sensors is now under an active development for the VXD. The sensors will be placed in several key positions in the vicinity of the interaction region. The severe space limitations require a challenging remote readout of the sensors.
Background compensation for a radiation level monitor
Keefe, D.J.
1975-12-01
Background compensation in a device such as a hand and foot monitor is provided by digital means using a scaler. With no radiation level test initiated, a scaler is down-counted from zero according to the background measured. With a radiation level test initiated, the scaler is up-counted from the previous down-count position according to the radiation emitted from the monitored object and an alarm is generated if, with the scaler having crossed zero in the positive going direction, a particular number is exceeded in a specific time period after initiation of the test. If the test is initiated while the scale is down-counting, the background count from the previous down- count stored in a memory is used as the initial starting point for the up-count.
Radiation monitoring container device (16-IML-1)
NASA Technical Reports Server (NTRS)
Nagaoka, S.
1992-01-01
In this experiment, layers of radiation detectors and biological specimens, bacterial spores (Bacillus subtillis), shrimp eggs (Altemia salina), and maize seeds (Zea mays) are sandwiched together in the Radiation Monitoring Container. The detectors, sheets of plastic materials, record the nuclear track of cosmic radiation. The dosimeter package contains conventional detectors made of materials such as lithium fluoride or magnesium-silica-terbium. The thermoluminescent materials (TLD) will, when moderately heated, emit luminescent photons linearly depending upon the dose of radiation received. The experiment, enclosed in a box-like container, is mounted on the aft end cone of the Spacelab, the area where the shielding is somewhat less than other locations.
Xue, Yuanyuan; Wang, Zujun; Chen, Wei; Liu, Minbo; He, Baoping; Yao, Zhibin; Sheng, Jiangkun; Ma, Wuying; Dong, Guantao; Jin, Junshan
2017-11-30
Four-transistor (T) pinned photodiode (PPD) CMOS image sensors (CISs) with four-megapixel resolution using 11µm pitch high dynamic range pixel were radiated with 3 MeV and 10MeV protons. The dark signal was measured pre- and post-radiation, with the dark signal post irradiation showing a remarkable increase. A theoretical method of dark signal distribution pre- and post-radiation is used to analyze the degradation mechanisms of the dark signal distribution. The theoretical results are in good agreement with experimental results. This research would provide a good understanding of the proton radiation effects on the CIS and make it possible to predict the dark signal distribution of the CIS under the complex proton radiation environments.
COMMUNITY-MONITORING PROGRAM SURROUNDING THE NEVADA TEST SITE: ONE YEAR OF EXPERIENCE
Since 1954, the US Public Health Service and later the US Environmental Protection Agency Laboratory in Las Vegas, Nevada, have been responsible for conducting a program of environmental radiation monitoring and public radiation safety associated with nuclear weapons tests conduc...
NASA Technical Reports Server (NTRS)
Schaefer, H. J.
1974-01-01
The complexity of direct reading and passive dosimeters for monitoring radiation is studied to strike the right balance of compromise to simplify the monitoring procedure. Trapped protons, tissue disintegration stars, and neutrons are analyzed.
Application of the thermoelectric MEMS microwave power sensor in a power radiation monitoring system
NASA Astrophysics Data System (ADS)
Bo, Gao; Jing, Yang; Si, Jiang; Debo, Wang
2016-08-01
A power radiation monitoring system based on thermoelectric MEMS microwave power sensors is studied. This monitoring system consists of three modules: a data acquisition module, a data processing and display module, and a data sharing module. It can detect the power radiation in the environment and the date information can be processed and shared. The measured results show that the thermoelectric MEMS microwave power sensor and the power radiation monitoring system both have a relatively good linearity. The sensitivity of the thermoelectric MEMS microwave power sensor is about 0.101 mV/mW, and the sensitivity of the monitoring system is about 0.038 V/mW. The voltage gain of the monitoring system is about 380 times, which is relatively consistent with the theoretical value. In addition, the low-frequency and low-power module in the monitoring system is adopted in order to reduce the electromagnetic pollution and the power consumption, and this work will extend the application of the thermoelectric MEMS microwave power sensor in more areas. Project supported by the National Natural Science Foundation of China (No. 11304158), the Province Natural Science Foundation of Jiangsu (No. BK20140890), the Open Research Fund of the Key Laboratory of MEMS of Ministry of Education, Southeast University (No. 3206005302), and the Scientific Research Foundation of Nanjing University of Posts and Telecommunications (Nos. NY213024, NY215139).
Aerosol radiative forcing from GEO satellite data over land surfaces
NASA Astrophysics Data System (ADS)
Costa, Maria J.; Silva, Ana M.
2005-10-01
Aerosols direct and indirect effects on the Earth's climate are widely recognized but have yet to be adequately quantified. Difficulties arise due to the very high spatial and temporal variability of aerosols, which is a major cause of uncertainties in radiative forcing studies. The effective monitoring of the global aerosol distribution is only made possible by satellite monitoring and this is the reason why the interest in aerosol observations from satellite passive radiometers is steadily increasing. From the point of view of the study of land surfaces, the atmosphere with its constituents represents an obscurant whose effects should be as much as possible eliminated, being this process sometimes referred to as atmospheric correction. In absence of clouds and using spectral intervals where gas absorption can be avoided to a great extent, only the aerosol effect remains to be corrected. The monitoring of the aerosol particles present in the atmosphere is then crucial to succeed in doing an accurate atmospheric correction, otherwise the surface properties may be inadequately characterised. However, the atmospheric correction over land surfaces turns out to be a difficult task since surface reflection competes with the atmospheric component of the signal. On the other hand, a single mean pre-established aerosol characterisation would not be sufficient for this purpose due to very high spatial and temporal variability of aerosols and their unpredictability, especially what concerns particulary intense "events" such as biomass burning and forest fires, desert dust episodes and volcanic eruptions. In this context, an operational methodology has been developed at the University of Evora - Evora Geophysics Centre (CGE), in the framework of the Satellite Application Facility for Land Surface Analysis - Land SAF, to derive an Aerosol Product from the Spinning Enhanced Visible and Infrared Imager (SEVIRI) data, flying on the Geostationary (GEO) satellite system Meteosat-8. The aerosol characterization obtained is used to calculate the fluxes and estimate the aerosol radiative forcing at the top of the atmosphere. The methodology along with the results of the aerosol properties and radiative forcing using SEVIRI images is presented. The aerosol optical thickness results are compared with ground-based measurements from the Aerosol Robotic NETwork (AERONET), to assess the accuracy of the methodology presented.
A novel multitarget model of radiation-induced cell killing based on the Gaussian distribution.
Zhao, Lei; Mi, Dong; Sun, Yeqing
2017-05-07
The multitarget version of the traditional target theory based on the Poisson distribution is still used to describe the dose-survival curves of cells after ionizing radiation in radiobiology and radiotherapy. However, noting that the usual ionizing radiation damage is the result of two sequential stochastic processes, the probability distribution of the damage number per cell should follow a compound Poisson distribution, like e.g. Neyman's distribution of type A (N. A.). In consideration of that the Gaussian distribution can be considered as the approximation of the N. A. in the case of high flux, a multitarget model based on the Gaussian distribution is proposed to describe the cell inactivation effects in low linear energy transfer (LET) radiation with high dose-rate. Theoretical analysis and experimental data fitting indicate that the present theory is superior to the traditional multitarget model and similar to the Linear - Quadratic (LQ) model in describing the biological effects of low-LET radiation with high dose-rate, and the parameter ratio in the present model can be used as an alternative indicator to reflect the radiation damage and radiosensitivity of the cells. Copyright © 2017 Elsevier Ltd. All rights reserved.
Abdul-Majid, S
1987-01-01
The characteristics of a 25.4 X 91 cm solar cell panel used as an x-ray and gamma-ray radiation monitor are presented. Applications for monitoring the primary x-ray beam are described at different values of operating currents and voltages as well as for directional dependence of scattered radiation. Other applications in gamma-ray radiography are also given. The detector showed linear response to both x-ray and gamma-ray exposures. The equipment is rigid, easy to use, relatively inexpensive and requires no power supply or any complex electronic equipment.
Solar radiative heating of fiber-optic cables used to monitor temperatures in water
NASA Astrophysics Data System (ADS)
Neilson, Bethany T.; Hatch, Christine E.; Ban, Heng; Tyler, Scott W.
2010-08-01
In recent years, applications of distributed temperature sensing (DTS) have increased in number and diversity. Because fiber-optic cables used for DTS are typically sheathed in dark UV-resistant materials, the question arises as to how shortwave solar radiation penetrating a water column influences the accuracy of absolute DTS-derived temperatures in aquatic applications. To quantify these effects, we completed a modeling effort that accounts for the effects of radiation and convection on a submersed cable to predict when solar heating may be important. Results indicate that for cables installed at shallow depths in clear, low-velocity water bodies, measurable heating of the cable is likely during peak solar radiation. However, at higher velocities, increased turbidity and/or greater depths, the effects of solar heating are immeasurable. A field study illustrated the effects of solar radiation by installing two types of fiber-optic cable at multiple water depths (from 0.05 to 0.8 m) in the center and along the sidewall of a trapezoidal canal. Thermistors were installed at similar depths and shielded from solar radiation to record absolute water temperatures. During peak radiation, thermistor data showed small temperature differences (˜0.003°C-0.04°C) between depths suggesting minor thermal stratification in the canal center. DTS data from cables at these same depths show differences of 0.01°C-0.17°C. The DTS differences cannot be explained by stratification alone and are likely evidence of additional heating from solar radiation. Sidewall thermistor strings also recorded stratification. However, corresponding DTS data suggested that bed conduction overwhelmed the effects of solar radiation.
Qin, Qi-Zhong; Chen, Yu; Fu, Ting-Ting; Ding, Li; Han, Ling-Li; Li, Jian-Chao
2012-03-01
To understand electromagnetic radiation field strength and its influencing factors of certain 110-kV high-voltage lines in one urban area of Chongqing by measuring 110-kV high-voltage line's electromagnetic radiation level. According to the methodology as determined by the National Hygienic Standards, we selected certain adjacent residential buildings, high-voltage lines along a specific street and selected different distances around its vertical projection point as monitoring points. The levels of electromagnetic radiations were measured respectively. In this investigation within the frequency of 5-1,000 Hz both the electric field strength and magnetic field strength of each monitoring sites were lower than the public exposure standards as determined by the International Commission on Non-Ionizing Radiation Protection. However, the electrical field strength on the roof adjacent to the high-voltage lines was significantly higher than that as measured on the other floors in the same buildings (p < 0.05). The electromagnetic radiation measurements of different monitoring points, under the same high-voltage lines, showed the location which is nearer the high-voltage line maintain a consistently higher level of radiation than the more distant locations (p < 0.05). Electromagnetic radiation generated by high-voltage lines decreases proportionally to the distance from the lines. The buildings can to some extent shield (or absorb) the electric fields generated by high-voltage lines nearby. The electromagnetic radiation intensity near high-voltage lines may be mitigated or intensified by the manner in which the high-voltage lines are set up, and it merits attention for the potential impact on human health.
Real Time Space Weather Support for Chandra X-ray Observatory Operations
NASA Technical Reports Server (NTRS)
O'Dell, Stephen L.; Miller, J. Scott; Minow, Joseph I.; Wolk, Scott J.; Aldcroft, Thomas L.; Spitzbart, Bradley D.; Swartz, Douglas A.
2012-01-01
NASA launched the Chandra X-ray Observatory in July 1999. Soon after first light in August 1999, however, degradation in the energy resolution and charge transfer efficiency of the Advanced CCD Imaging Spectrometer (ACIS) x-ray detectors was observed. The source of the degradation was quickly identified as radiation damage in the charge-transfer channel of the front-illuminated CCDs, by weakly penetrating ("soft", 100-500 keV) protons as Chandra passed through the Earth s radiation belts and ring currents. As soft protons were not considered a risk to spacecraft health before launch, the only on-board radiation monitoring system is the Electron, Proton, and Helium Instrument (EPHIN) which was included on Chandra with the primary purpose of monitoring energetic solar particle events. Further damage to the ACIS detector has been successfully mitigated through a combination of careful mission planning, autonomous on-board radiation protection, and manual intervention based upon real-time monitoring of the soft-proton environment. The AE-8 and AP-8 trapped radiation models and Chandra Radiation Models are used to schedule science operations in regions of low proton flux. EPHIN has been used as the primary autonomous in-situ radiation trigger; but, it is not sensitive to the soft protons that damage the front-illuminated CCDs. Monitoring of near-real-time space weather data sources provides critical information on the proton environment outside the Earth's magnetosphere due to solar proton events and other phenomena. The operations team uses data from the Geostationary Operational Environmental Satellites (GOES) to provide near-real-time monitoring of the proton environment; however, these data do not give a representative measure of the soft-proton (less than 1 MeV) flux in Chandra s high elliptical orbit. The only source of relevant measurements of sub-MeV protons is the Electron, Proton, and Alpha Monitor (EPAM) aboard the Advanced Composition Explorer (ACE) satellite at L1, with real-time data provided by NOAA's Space Weather Prediction Center. This presentation will discuss radiation mitigation against proton damage, including models and real-time data sources used to protect the ACIS detector system.
Real Time Space Weather Support for Chandra X-Ray Observatory Operations
NASA Technical Reports Server (NTRS)
O'Dell, Stephen L.; Minow, Joseph I.; Miller, J. Scott; Wolk, Scott J.; Aldcroft, Thomas L.; Spitzbart, Bradley D.; Swartz. Douglas A.
2012-01-01
NASA launched the Chandra X-ray Observatory in July 1999. Soon after first light in August 1999, however, degradation in the energy resolution and charge transfer efficiency of the Advanced CCD Imaging Spectrometer (ACIS) x-ray detectors was observed. The source of the degradation was quickly identified as radiation damage in the charge-transfer channel of the front-illuminated CCDs, by weakly penetrating ( soft , 100 500 keV) protons as Chandra passed through the Earth s radiation belts and ring currents. As soft protons were not considered a risk to spacecraft health before launch, the only on-board radiation monitoring system is the Electron, Proton, and Helium Instrument (EPHIN) which was included on Chandra with the primary purpose of monitoring energetic solar particle events. Further damage to the ACIS detector has been successfully mitigated through a combination of careful mission planning, autonomous on-board radiation protection, and manual intervention based upon real-time monitoring of the soft-proton environment. The AE-8 and AP-8 trapped radiation models and Chandra Radiation Models are used to schedule science operations in regions of low proton flux. EPHIN has been used as the primary autonomous in-situ radiation trigger; but, it is not sensitive to the soft protons that damage the front-illuminated CCDs. Monitoring of near-real-time space weather data sources provides critical information on the proton environment outside the Earth s magnetosphere due to solar proton events and other phenomena. The operations team uses data from the Geostationary Operational Environmental Satellites (GOES) to provide near-real-time monitoring of the proton environment; however, these data do not give a representative measure of the soft-proton (< 1 MeV) flux in Chandra s high elliptical orbit. The only source of relevant measurements of sub-MeV protons is the Electron, Proton, and Alpha Monitor (EPAM) aboard the Advanced Composition Explorer (ACE) satellite at L1, with real-time data provided by NOAA s Space Weather Prediction Center. This presentation describes the radiation mitigation strategies to minimize the proton damage in the ACIS CCD detectors and the importance of real-time data sources that are used to protect the ACIS detector system from space weather events.
Real Time Space Weather Support for Chandra X-ray Observatory Operations
NASA Astrophysics Data System (ADS)
O'Dell, S. L.; Miller, S.; Minow, J. I.; Wolk, S.; Aldcroft, T. L.; Spitzbart, B. D.; Swartz, D. A.
2012-12-01
NASA launched the Chandra X-ray Observatory in July 1999. Soon after first light in August 1999, however, degradation in the energy resolution and charge transfer efficiency of the Advanced CCD Imaging Spectrometer (ACIS) x-ray detectors was observed. The source of the degradation was quickly identified as radiation damage in the charge-transfer channel of the front-illuminated CCDs, by weakly penetrating ("soft", 100-500 keV) protons as Chandra passed through the Earth's radiation belts and ring currents. As soft protons were not considered a risk to spacecraft health before launch, the only on-board radiation monitoring system is the Electron, Proton, and Helium Instrument (EPHIN) which was included on Chandra with the primary purpose of monitoring energetic solar particle events. Further damage to the ACIS detector has been successfully mitigated through a combination of careful mission planning, autonomous on-board radiation protection, and manual intervention based upon real-time monitoring of the soft-proton environment. The AE-8 and AP-8 trapped radiation models and Chandra Radiation Models are used to schedule science operations in regions of low proton flux. EPHIN has been used as the primary autonomous in-situ radiation trigger; but, it is not sensitive to the soft protons that damage the front-illuminated CCDs. Monitoring of near-real-time space weather data sources provides critical information on the proton environment outside the Earth's magnetosphere due to solar proton events and other phenomena. The operations team uses data from the Geostationary Operational Environmental Satellites (GOES) to provide near-real-time monitoring of the proton environment; however, these data do not give a representative measure of the soft-proton (< 1 MeV) flux in Chandra's high elliptical orbit. The only source of relevant measurements of sub-MeV protons is the Electron, Proton, and Alpha Monitor (EPAM) aboard the Advanced Composition Explorer (ACE) satellite at L1, with real-time data provided by NOAA's Space Weather Prediction Center. This presentation will discuss radiation mitigation against proton damage, including models and real-time data sources used to protect the ACIS detector system.
Monitoring, Analyzing and Assessing Radiation Belt Loss and Energization
NASA Astrophysics Data System (ADS)
Daglis, I. A.; Bourdarie, S.; Khotyaintsev, Y.; Santolik, O.; Horne, R.; Mann, I.; Turner, D.; Anastasiadis, A.; Angelopoulos, V.; Balasis, G.; Chatzichristou, E.; Cully, C.; Georgiou, M.; Glauert, S.; Grison, B.; Kolmasova, I.; Lazaro, D.; Macusova, E.; Maget, V.; Papadimitriou, C.; Ropokis, G.; Sandberg, I.; Usanova, M.
2012-09-01
We present the concept, objectives and expected impact of the MAARBLE (Monitoring, Analyzing and Assessing Radiation Belt Loss and Energization) project, which is being implemented by a consortium of seven institutions (five European, one Canadian and one US) with support from the European Community's Seventh Framework Programme. The MAARBLE project employs multi-spacecraft monitoring of the geospace environment, complemented by ground-based monitoring, in order to analyze and assess the physical mechanisms leading to radiation belt particle energization and loss. Particular attention is paid to the role of ULF/VLF waves. A database containing properties of the waves is being created and will be made available to the scientific community. Based on the wave database, a statistical model of the wave activity dependent on the level of geomagnetic activity, solar wind forcing, and magnetospheric region will be developed. Furthermore, we will incorporate multi-spacecraft particle measurements into data assimilation tools, aiming at a new understanding of the causal relationships between ULF/VLF waves and radiation belt dynamics. Data assimilation techniques have been proven to be a valuable tool in the field of radiation belts, able to guide 'the best' estimate of the state of a complex system.
An investigation was made of factors affecting the use of commercially-produced CaF2:Mn thermoluminescent dosimeters for low level environmental radiation monitoring. Calibration factors and self-dosing rates were quantified for 150 thermoluminescent dosimeters. Laboratory studie...
Code of Federal Regulations, 2010 CFR
2010-01-01
... COMMISSION STANDARDS FOR PROTECTION AGAINST RADIATION Surveys and Monitoring § 20.1501 General. (a) Each licensee shall make or cause to be made, surveys that— (1) May be necessary for the licensee to comply with... used for quantitative radiation measurements (e.g., dose rate and effluent monitoring) are calibrated...
Code of Federal Regulations, 2011 CFR
2011-01-01
... COMMISSION STANDARDS FOR PROTECTION AGAINST RADIATION Surveys and Monitoring § 20.1501 General. (a) Each licensee shall make or cause to be made, surveys that— (1) May be necessary for the licensee to comply with... used for quantitative radiation measurements (e.g., dose rate and effluent monitoring) are calibrated...
DOE Office of Scientific and Technical Information (OSTI.GOV)
Derenzo, Stephen E.; Moses, William W.
An embodiment of a liquid chromatography detection unit includes a fluid channel and a radiation detector. The radiation detector is operable to image a distribution of a radiolabeled compound as the distribution travels along the fluid channel. An embodiment of a liquid chromatography system includes an injector, a separation column, and a radiation detector. The injector is operable to inject a sample that includes a radiolabeled compound into a solvent stream. The position sensitive radiation detector is operable to image a distribution of the radiolabeled compound as the distribution travels along a fluid channel. An embodiment of a method ofmore » liquid chromatography includes injecting a sample that comprises radiolabeled compounds into a solvent. The radiolabeled compounds are then separated. A position sensitive radiation detector is employed to image distributions of the radiolabeled compounds as the radiolabeled compounds travel along a fluid channel.« less
Individual Radiation Protection Monitoring in the Marshall Islands: Rongelap Atoll (2002-2004)
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hamilton, T F; Kehl, S; Hickman, D
2006-01-17
The United States Department of Energy (U.S. DOE) has recently implemented a series of strategic initiatives to address long-term radiological surveillance needs at former U.S. nuclear test sites in the Marshall Islands. The plan is to engage local atoll communities in developing shared responsibilities for implementing radiation protection monitoring programs for resettled and resettling populations in the northern Marshall Islands. Using the pooled resources of the U.S. DOE and local atoll governments, individual radiological surveillance programs have been developed in whole body counting and plutonium urinalysis in order to accurately assess radiation doses resulting from the ingestion and uptake ofmore » fallout radionuclides contained in locally grown foods. Permanent whole body counting facilities have been established at three separate locations in the Marshall Islands including Rongelap Atoll (Figure 1). These facilities are operated and maintained by Marshallese technicians with scientists from the Lawrence Livermore National Laboratory (LLNL) providing on-going technical support services. Bioassay samples are collected under controlled conditions and analyzed for plutonium isotopes at the Center for Accelerator Mass Spectrometry at LLNL using state-of-the art measurement technologies. We also conduct an on-going environmental monitoring and characterization program at selected sites in the northern Marshall Islands. The aim of the environmental program is to determine the level and distribution of important fallout radionuclides in soil, water and local foods with a view towards providing more accurate and updated dose assessments, incorporating knowledge of the unique behaviors and exposure pathways of fallout radionuclides in coral atoll ecosystems. These scientific studies have also been essential in helping guide the development of remedial options used in support of island resettlement. Together, the individual and environmental radiological surveillance programs are helping meet the informational needs of the U.S. DOE and the Republic of the Marshall Islands. Our updated environmental assessments provide a strong scientific basis for predicting future change in exposure conditions especially in relation to changes in lifestyle, diet and/or land-use patterns. This information has important implications in addressing questions about existing (and future) radiological conditions on the islands, in determining as well as the implementation, cost and effectiveness of potential intervention options, and in general policy support considerations. Perhaps most importantly, the recently established individual radiological surveillance programs provide affected atoll communities with an unprecedented level of radiation protection monitoring where, for the first time, local resources are being made available to monitor resettled and resettling populations on a continuous basis. As a hard copy supplement to Marshall Islands Program website (http://eed.llnl.gov/mi/), this document provides an overview of the individual radiation protection monitoring program established for resettlement workers living on Rongelap Island along with a full disclosure of all verified measurement data (2002-2004). Readers are advised that an additional feature of the associated web site is a provision where users are able calculate and track doses delivered to volunteers (de-identified information only) participating the Marshall Islands Radiological Surveillance Program.« less
Individual Radiation Protection Monitoring in the Marshall Islands: Enewetak Atoll (2002-2004)
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hamilton, T F; Kehl, S; Hickman, D
2006-01-17
The United States Department of Energy (U.S. DOE) has recently implemented a series of strategic initiatives to address long-term radiological surveillance needs at former U.S. nuclear test sites in the Marshall Islands. The plan is to engage local atoll communities in developing shared responsibilities for implementing radiation protection monitoring programs for resettled and resettling populations in the northern Marshall Islands. Using the pooled resources of the U.S. DOE and local atoll governments, individual radiological surveillance programs have been developed in whole body counting and plutonium urinalysis in order to accurately assess radiation doses resulting from the ingestion and uptake ofmore » fallout radionuclides contained in locally grown foods. Permanent whole body counting facilities have been established at three separate locations in the Marshall Islands including Enewetak Island (Figure 1) (Bell et al., 2002). These facilities are operated and maintained by Marshallese technicians with scientists from the Lawrence Livermore National Laboratory (LLNL) providing on-going technical support services. Bioassay samples are collected under controlled conditions and analyzed for plutonium isotopes at the Center for Accelerator Mass Spectrometry at LLNL using state-of-the art measurement technologies. We also conduct an on-going environmental monitoring and characterization program at selected sites in the northern Marshall Islands. The aim of the environmental program is to determine the level and distribution of important fallout radionuclides in soil, water and local foods with a view towards providing more accurate and updated dose assessments, incorporating knowledge of the unique behaviors and exposure pathways of fallout radionuclides in coral atoll ecosystems. These scientific studies have also been essential in helping guide the development of remedial options used in support of island resettlement. Together, the individual and environmental radiological surveillance programs are helping meet the informational needs of the U.S. DOE and the Republic of the Marshall Islands. Our updated environmental assessments provide a strong scientific basis for predicting future change in exposure conditions especially in relation to changes in lifestyle, diet and/or land-use patterns. This information has important implications in addressing questions about existing (and future) radiological conditions on the islands, in determining the cost and estimating the effectiveness of potential remedial measures, and in general policy support considerations. Perhaps most importantly, the recently established individual radiological surveillance programs provide affected atoll communities with an unprecedented level of radiation protection monitoring where, for the first time, local resources are being made available to monitor resettled and resettling populations on a continuous basis. As a hard copy supplement to Marshall Islands Program website (http://eed.llnl.gov/mi/), this document provides an overview of the individual radiation protection monitoring program established for the Enewetak Atoll population group along with a full disclosure of all verified measurement data (2002-2004). Readers are advised that an additional feature of the associated web site is a provision where users are able calculate and track doses delivered to volunteers (de-identified information only) participating in the Marshall Islands Radiological Surveillance Program.« less
Ding, George X; Malcolm, Arnold W
2013-09-07
There is a growing interest in patient exposure resulting from an x-ray imaging procedure used in image-guided radiation therapy. This study explores a feasibility to use a commercially available optically stimulated luminescence (OSL) dosimeter, nanoDot, for estimating imaging radiation exposure to patients. The kilovoltage x-ray sources used for kV-cone-beam CT (CBCT) imaging acquisition procedures were from a Varian on-board imager (OBI) image system. An ionization chamber was used to determine the energy response of nanoDot dosimeters. The chamber calibration factors for x-ray beam quality specified by half-value layer were obtained from an Accredited Dosimetry Calibration Laboratory. The Monte Carlo calculated dose distributions were used to validate the dose distributions measured by using the nanoDot dosimeters in phantom and in vivo. The range of the energy correction factors for the nanoDot as a function of photon energy and bow-tie filters was found to be 0.88-1.13 for different kVp and bow-tie filters. Measurement uncertainties of nanoDot were approximately 2-4% after applying the energy correction factors. The tests of nanoDot placed on a RANDO phantom and on patient's skin showed consistent results. The nanoDot is suitable dosimeter for in vivo dosimetry due to its small size and manageable energy dependence. The dosimeter placed on a patient's skin has potential to serve as an experimental method to monitor and to estimate patient exposure resulting from a kilovoltage x-ray imaging procedure. Due to its large variation in energy response, nanoDot is not suitable to measure radiation doses resulting from mixed beams of megavoltage therapeutic and kilovoltage imaging radiations.
NASA Astrophysics Data System (ADS)
Ding, George X.; Malcolm, Arnold W.
2013-09-01
There is a growing interest in patient exposure resulting from an x-ray imaging procedure used in image-guided radiation therapy. This study explores a feasibility to use a commercially available optically stimulated luminescence (OSL) dosimeter, nanoDot, for estimating imaging radiation exposure to patients. The kilovoltage x-ray sources used for kV-cone-beam CT (CBCT) imaging acquisition procedures were from a Varian on-board imager (OBI) image system. An ionization chamber was used to determine the energy response of nanoDot dosimeters. The chamber calibration factors for x-ray beam quality specified by half-value layer were obtained from an Accredited Dosimetry Calibration Laboratory. The Monte Carlo calculated dose distributions were used to validate the dose distributions measured by using the nanoDot dosimeters in phantom and in vivo. The range of the energy correction factors for the nanoDot as a function of photon energy and bow-tie filters was found to be 0.88-1.13 for different kVp and bow-tie filters. Measurement uncertainties of nanoDot were approximately 2-4% after applying the energy correction factors. The tests of nanoDot placed on a RANDO phantom and on patient's skin showed consistent results. The nanoDot is suitable dosimeter for in vivo dosimetry due to its small size and manageable energy dependence. The dosimeter placed on a patient's skin has potential to serve as an experimental method to monitor and to estimate patient exposure resulting from a kilovoltage x-ray imaging procedure. Due to its large variation in energy response, nanoDot is not suitable to measure radiation doses resulting from mixed beams of megavoltage therapeutic and kilovoltage imaging radiations.
NASA Astrophysics Data System (ADS)
Pavez, Cristian; Pedreros, José; Zambra, Marcelo; Veloso, Felipe; Moreno, José; Ariel, Tarifeño-Saldivia; Soto, Leopoldo
2012-10-01
Currently, a new generation of small plasma foci devices is being developed and researched, motivated by its potential use as portable sources of x-ray and neutron pulsed radiation for several applications. In this work, experimental results of the accumulated x-ray dose angular distribution and characterization of the x-ray source size are presented for a small and fast plasma focus device, ‘PF-400J’ (880 nF, 40 nH, 27-29 kV, ˜350 J, T/4 ˜ 300 ns). The experimental device is operated using hydrogen as the filling gas in a discharge region limited by a volume of around 80 cm3. The x-ray radiation is monitored, shot by shot, using a scintillator-photomultiplier system located outside the vacuum chamber at 2.3 m far away from the radiation emission region. The angular x-ray dose distribution measurement shows a well-defined emission cone, with an expansion angle of 5°, which is observed around the plasma focus device symmetry axis using TLD-100 crystals. The x-ray source size measurements are obtained using two image-forming aperture techniques: for both cases, one small (pinhole) and one large for the penumbral imaging. These results are in agreement with the drilling made by the energetic electron beam coming from the pinch region. Additionally, some examples of image radiographic applications are shown in order to highlight the real possibilities of the plasma focus device as a portable x-ray source. In the light of the obtained results and the scaling laws observed in plasma foci devices, we present a discussion on the potentiality and advantages of these devices as pulsed and safe sources of x-radiation for applications.
Radiation Detection for Homeland Security Applications
NASA Astrophysics Data System (ADS)
Ely, James
2008-05-01
In the past twenty years or so, there have been significant changes in the strategy and applications for homeland security. Recently there have been significant at deterring and interdicting terrorists and associated organizations. This is a shift in the normal paradigm of deterrence and surveillance of a nation and the `conventional' methods of warfare to the `unconventional' means that terrorist organizations resort to. With that shift comes the responsibility to monitor international borders for weapons of mass destruction, including radiological weapons. As a result, countries around the world are deploying radiation detection instrumentation to interdict the illegal shipment of radioactive material crossing international borders. These efforts include deployments at land, rail, air, and sea ports of entry in the US and in European and Asian countries. Radioactive signatures of concern include radiation dispersal devices (RDD), nuclear warheads, and special nuclear material (SNM). Radiation portal monitors (RPMs) are used as the main screening tool for vehicles and cargo at borders, supplemented by handheld detectors, personal radiation detectors, and x-ray imaging systems. This talk will present an overview of radiation detection equipment with emphasis on radiation portal monitors. In the US, the deployment of radiation detection equipment is being coordinated by the Domestic Nuclear Detection Office within the Department of Homeland Security, and a brief summary of the program will be covered. Challenges with current generation systems will be discussed as well as areas of investigation and opportunities for improvements. The next generation of radiation portal monitors is being produced under the Advanced Spectroscopic Portal program and will be available for deployment in the near future. Additional technologies, from commercially available to experimental, that provide additional information for radiation screening, such as density imaging equipment, will be reviewed. Opportunities for further research and development to improve the current equipment and methodologies for radiation detection for the important task of homeland security will be the final topic to be discussed.
A Spacecraft Housekeeping System-on-Chip in a Radiation Hardened Structured ASIC
NASA Technical Reports Server (NTRS)
Suarez, George; DuMonthier, Jeffrey J.; Sheikh, Salman S.; Powell, Wesley A.; King, Robyn L.
2012-01-01
Housekeeping systems are essential to health monitoring of spacecraft and instruments. Typically, sensors are distributed across various sub-systems and data is collected using components such as analog-to-digital converters, analog multiplexers and amplifiers. In most cases programmable devices are used to implement the data acquisition control and storage, and the interface to higher level systems. Such discrete implementations require additional size, weight, power and interconnect complexity versus an integrated circuit solution, as well as the qualification of multiple parts. Although commercial devices are readily available, they are not suitable for space applications due the radiation tolerance and qualification requirements. The Housekeeping System-o n-A-Chip (HKSOC) is a low power, radiation hardened integrated solution suitable for spacecraft and instrument control and data collection. A prototype has been designed and includes a wide variety of functions including a 16-channel analog front-end for driving and reading sensors, analog-to-digital and digital-to-analog converters, on-chip temperature sensor, power supply current sense circuits, general purpose comparators and amplifiers, a 32-bit processor, digital I/O, pulse-width modulation (PWM) generators, timers and I2C master and slave serial interfaces. In addition, the device can operate in a bypass mode where the processor is disabled and external logic is used to control the analog and mixed signal functions. The device is suitable for stand-alone or distributed systems where multiple chips can be deployed across different sub-systems as intelligent nodes with computing and processing capabilities.
Bradford, J.; Bell, S. A.; Wilkinson, J.; Smith, D.; Tudor, S.
2016-01-01
The total solar eclipse that occurred over the Arctic region on 20 March 2015 was seen as a partial eclipse over much of Europe. Observations of this eclipse were used to investigate the high time resolution (1 min) decay and recovery of the Earth’s ionospheric E-region above the ionospheric monitoring station in Chilton, UK. At the altitude of this region (100 km), the maximum phase of the eclipse was 88.88% obscuration of the photosphere occurring at 9:29:41.5 UT. In comparison, the ionospheric response revealed a maximum obscuration of 66% (leaving a fraction, Φ, of uneclipsed radiation of 34±4%) occurring at 9:29 UT. The eclipse was re-created using data from the Solar Dynamics Observatory to estimate the fraction of radiation incident on the Earth’s atmosphere throughout the eclipse from nine different emission wavelengths in the extreme ultraviolet (EUV) and X-ray spectrum. These emissions, having varying spatial distributions, were each obscured differently during the eclipse. Those wavelengths associated with coronal emissions (94, 211 and 335 Å) most closely reproduced the time varying fraction of unobscured radiation observed in the ionosphere. These results could enable historic ionospheric eclipse measurements to be interpreted in terms of the distribution of EUV and X-ray emissions on the solar disc. This article is part of the themed issue ‘Atmospheric effects of solar eclipses stimulated by the 2015 UK eclipse’. PMID:27550766
Scott, C J; Bradford, J; Bell, S A; Wilkinson, J; Barnard, L; Smith, D; Tudor, S
2016-09-28
The total solar eclipse that occurred over the Arctic region on 20 March 2015 was seen as a partial eclipse over much of Europe. Observations of this eclipse were used to investigate the high time resolution (1 min) decay and recovery of the Earth's ionospheric E-region above the ionospheric monitoring station in Chilton, UK. At the altitude of this region (100 km), the maximum phase of the eclipse was 88.88% obscuration of the photosphere occurring at 9:29:41.5 UT. In comparison, the ionospheric response revealed a maximum obscuration of 66% (leaving a fraction, Φ, of uneclipsed radiation of 34±4%) occurring at 9:29 UT. The eclipse was re-created using data from the Solar Dynamics Observatory to estimate the fraction of radiation incident on the Earth's atmosphere throughout the eclipse from nine different emission wavelengths in the extreme ultraviolet (EUV) and X-ray spectrum. These emissions, having varying spatial distributions, were each obscured differently during the eclipse. Those wavelengths associated with coronal emissions (94, 211 and 335 Å) most closely reproduced the time varying fraction of unobscured radiation observed in the ionosphere. These results could enable historic ionospheric eclipse measurements to be interpreted in terms of the distribution of EUV and X-ray emissions on the solar disc.This article is part of the themed issue 'Atmospheric effects of solar eclipses stimulated by the 2015 UK eclipse'. © 2016 The Author(s).
Packet personal radiation monitor
Phelps, J.E.
1988-03-31
A personal radiation monitor of the chirper type is provided for detecting ionizing radiation. A battery powered high voltage power supply is used to generate and apply a high voltage bias to a G-M tube radiation sensor. The high voltage is monitored by a low-loss sensing network which generates a feedback signal to control the high voltage power supply such that the high voltage bias is recharged to +500 VDC when the current pulses of the sensor, generated by the detection of ionizing radiatonevents, discharges the high voltage bias to +450 VDC. During the high voltage recharge period an audio transducer is activated to produce an audible ''chirp''. The rate of the ''chirps'' is controlled by the rate at which the high voltage bias is recharged, which is proportional to the radiation field intensity to which the sensor is exposed. The chirp rate sensitivity is set to be approximately 1.5 (chirps/min/MR/hr.). The G-M tube sensor is used in a current sensing mode so that the device does not paralyze in a high radiation field. 2 figs.
2007 Annual Health Physics Report for the HEU Transparency Program
DOE Office of Scientific and Technical Information (OSTI.GOV)
Radev, R
2008-04-09
During the 2007 calendar year, Lawrence Livermore National Laboratory (LLNL) provided health physics support for the Highly Enriched Uranium (HEU) Transparency Program for external and internal radiation protection and technical expertise related to BDMS radioactive sources and Russian radiation safety regulatory compliance. For the calendar year 2007, there were 172 person-trips that required dose monitoring of the U.S. monitors. Of the 172 person-trips, 160 person-trips were SMVs and 12 person-trips were Transparency Monitoring Office (TMO) trips. There were 12 monitoring visits by TMO monitors to facilities other than UEIE and 10 to UEIE itself. There were two monitoring visits (sourcemore » changes) that were back to back with 14 monitors. LLNL's Hazard Control Division laboratories provided the dosimetry services for the HEU Transparency monitors.« less
NASA Astrophysics Data System (ADS)
Uglov, A. A.; Smurov, I. Yu; Gus'kov, A. G.; Aksenov, L. V.
1990-08-01
A theoretical study is reported of melting and thermocapillary convection under the action of laser radiation with a nonmonotonic spatial distribution of the power density. An analysis is made of changes in the geometry of the molten bath with time. The transition from a nonmonotonic boundary of a melt, corresponding to the spatial distribution of the radiation, to a monotonic one occurs in a time of the order of 1 ms when the power density of laser radiation is 105 W/cm2. The vortex structure of the flow in the molten bath is governed by the spatial distribution of the laser radiation in such a way that each local power density maximum corresponds to two vortices with oppositely directed velocity components.
NASA Technical Reports Server (NTRS)
Levine, D. M.
1978-01-01
Radiation from lightning in the RF band from 3-300 MHz were monitored. Radiation in this frequency range is of interest as a potential vehicle for monitoring severe storms and for studying the lightning itself. Simultaneous measurements were made of RF radiation and fast and slow field changes. Continuous analogue recordings with a system having 300 kHz of bandwidth were made together with digital records of selected events (principally return strokes) at greater temporal resolution. The data reveal patterns in the RF radiation for the entire flash which are characteristic of flash type and independent of the frequency of observation. Individual events within the flash also have characteristic RF patterns. Strong radiation occurs during the first return strokes, but delayed about 20 micron sec with respect to the begining of the return stroke; whereas, RF radiation from subsequent return strokes tends to be associated with cloud processes preceding the flash with comparatively little radiation occurring during the return stroke itself.
Mobile autonomous robotic apparatus for radiologic characterization
Dudar, Aed M.; Ward, Clyde R.; Jones, Joel D.; Mallet, William R.; Harpring, Larry J.; Collins, Montenius X.; Anderson, Erin K.
1999-01-01
A mobile robotic system that conducts radiological surveys to map alpha, beta, and gamma radiation on surfaces in relatively level open areas or areas containing obstacles such as stored containers or hallways, equipment, walls and support columns. The invention incorporates improved radiation monitoring methods using multiple scintillation detectors, the use of laser scanners for maneuvering in open areas, ultrasound pulse generators and receptors for collision avoidance in limited space areas or hallways, methods to trigger visible alarms when radiation is detected, and methods to transmit location data for real-time reporting and mapping of radiation locations on computer monitors at a host station. A multitude of high performance scintillation detectors detect radiation while the on-board system controls the direction and speed of the robot due to pre-programmed paths. The operators may revise the preselected movements of the robotic system by ethernet communications to remonitor areas of radiation or to avoid walls, columns, equipment, or containers. The robotic system is capable of floor survey speeds of from 1/2-inch per second up to about 30 inches per second, while the on-board processor collects, stores, and transmits information for real-time mapping of radiation intensity and the locations of the radiation for real-time display on computer monitors at a central command console.
Mobile autonomous robotic apparatus for radiologic characterization
Dudar, A.M.; Ward, C.R.; Jones, J.D.; Mallet, W.R.; Harpring, L.J.; Collins, M.X.; Anderson, E.K.
1999-08-10
A mobile robotic system is described that conducts radiological surveys to map alpha, beta, and gamma radiation on surfaces in relatively level open areas or areas containing obstacles such as stored containers or hallways, equipment, walls and support columns. The invention incorporates improved radiation monitoring methods using multiple scintillation detectors, the use of laser scanners for maneuvering in open areas, ultrasound pulse generators and receptors for collision avoidance in limited space areas or hallways, methods to trigger visible alarms when radiation is detected, and methods to transmit location data for real-time reporting and mapping of radiation locations on computer monitors at a host station. A multitude of high performance scintillation detectors detect radiation while the on-board system controls the direction and speed of the robot due to pre-programmed paths. The operators may revise the preselected movements of the robotic system by ethernet communications to remonitor areas of radiation or to avoid walls, columns, equipment, or containers. The robotic system is capable of floor survey speeds of from 1/2-inch per second up to about 30 inches per second, while the on-board processor collects, stores, and transmits information for real-time mapping of radiation intensity and the locations of the radiation for real-time display on computer monitors at a central command console. 4 figs.
The Projection of Space Radiation Environments with a Solar Cycle Statistical Model
NASA Technical Reports Server (NTRS)
Kim, Myung-Hee; Cucinotta, Francis A.; Wilson, John W.
2006-01-01
A solar cycle statistical model has been developed to project sunspot numbers which represent the variations in the space radiation environment. The resultant projection of sunspot numbers in near future were coupled to space-related quantities of interest in radiation protection, such as the galactic cosmic radiation (GCR) deceleration potential (f) and the mean occurrence frequency of solar particle event (SPE). Future GCR fluxes have been derived from a predictive model, in which GCR temporal dependence represented by f was derived from GCR flux and ground-based Climax neutron monitor rate measurements over the last four decades. Results showed that the point dose equivalent inside a typical spacecraft in interplanetary radiation fields was influenced by solar modulation up to a factor of three. One important characteristic of sporadic SPEs is their mean frequency of occurrence, which is dependent on solar activity. Projections of future mean frequency of SPE occurrence were estimated from a power law function of sunspot number. Furthermore, the cumulative probabilities of SPE during short-period missions were defined with the continuous database of proton fluences of SPE. The analytic representation of energy spectra of SPE was constructed by the Weibull distribution for different event sizes. The representative exposure level at each event size was estimated for the guideline of protection systems for astronauts during future space exploration missions.
Kolotkov, Gennady; Penin, Sergei
2013-01-01
The Fukushima nuclear accident showed the importance of timely monitoring and detection of radioactive emissions released from enterprises of the nuclear fuel cycle. Nuclear power plants (NPP) working continuously are a stationary source of gas-aerosol emissions which presented in a ground surface layer persistently. Following radioactive emission, untypical effects can be observed, for example: the occurrences of areas with increased ionization, and increased concentration of some gases caused by photochemical reactions. The gases themselves and their characteristic radiation can be markers of radioactivity and can be monitored by a passive method. Hydrogen atom (H) and hydroxyl radical (OH) are formed in a radioactive plume by radiolysis of water molecules and other hydrogen-containing air components by the high energy electrons from beta-decay of radionuclides. The hydrogen atom and hydroxyl radical can spontaneously radiate at 1420 MHz and 1665-1667 MHz respectively. The passive method of remote monitoring of radiation levels using radio-frequencies of H and OH from radioactive emissions of NPP is described. The model data is indicative of the monitoring of radiation levels using these frequencies. Crown Copyright © 2012. Published by Elsevier Ltd. All rights reserved.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Gallegos, G; Bertoldo, N A; Campbell, C G
The purposes of the Lawrence Livermore National Laboratory Environmental Report 2008 are to record Lawrence Livermore National Laboratory's (LLNL's) compliance with environmental standards and requirements, describe LLNL's environmental protection and remediation programs, and present the results of environmental monitoring at the two LLNL sites - the Livermore site and Site 300. The report is prepared for the U.S. Department of Energy (DOE) by LLNL's Environmental Protection Department. Submittal of the report satisfies requirements under DOE Order 231.1A, Environmental Safety and Health Reporting, and DOE Order 5400.5, Radiation Protection of the Public and Environment. The report is distributed electronically and ismore » available at https://saer.lln.gov/, the website for the LLNL annual environmental report. Previous LLNL annual environmental reports beginning in 1994 are also on the website. Some references in the electronic report text are underlined, which indicates that they are clickable links. Clicking on one of these links will open the related document, data workbook, or website that it refers to. The report begins with an executive summary, which provides the purpose of the report and an overview of LLNL's compliance and monitoring results. The first three chapters provide background information: Chapter 1 is an overview of the location, meteorology, and hydrogeology of the two LLNL sites; Chapter 2 is a summary of LLNL's compliance with environmental regulations; and Chapter 3 is a description of LLNL's environmental programs with an emphasis on the Environmental Management System including pollution prevention. The majority of the report covers LLNL's environmental monitoring programs and monitoring data for 2008: effluent and ambient air (Chapter 4); waters, including wastewater, storm water runoff, surface water, rain, and groundwater (Chapter 5); and terrestrial, including soil, sediment, vegetation, foodstuff, ambient radiation, and special status wildlife and plants (Chapter 6). Complete monitoring data, which are summarized in the body of the report, are provided in Appendix A. The remaining three chapters discuss the radiological impact on the public from LLNL operations (Chapter 7), LLNL's groundwater remediation program (Chapter 8), and quality assurance for the environmental monitoring programs (Chapter 9). The report uses Systeme International units, consistent with the federal Metric Conversion Act of 1975 and Executive Order 12770, Metric Usage in Federal Government Programs (1991). For ease of comparison to environmental reports issued prior to 1991, dose values and many radiological measurements are given in both metric and U.S. customary units. A conversion table is provided in the glossary. The report is the responsibility of LLNL's Environmental Protection Department. Monitoring data were obtained through the combined efforts of the Environmental Protection Department; Environmental Restoration Department; Physical and Life Sciences Environmental Monitoring Radiation Laboratory; and the Hazards Control Department.« less
NASA Technical Reports Server (NTRS)
Watson, R. T.; Geller, M. A.; Stolarski, R. S.; Hampson, R. F.
1986-01-01
The state of knowledge of the upper atmosphere was assessed as of January 1986. The physical, chemical, and radiative processes which control the spatial and temporal distribution of ozone in the atmosphere; the predicted magnitude of ozone perturbations and climate changes for a variety of trace gas scenarios; and the ozone and temperature data used to detect the presence or absence of a long term trend were discussed. This assessment report was written by a small group of NASA scientists, was peer reviewed, and is based primarily on the comprehensive international assessment document entitled Atmospheric Ozone 1985: Assessment of Our Understanding of the Processes Controlling Its Present Distribution and Change, to be published as the World Meteorological Organization Global Ozone Research and Monitoring Project Report No. 16.
10 CFR 20.2106 - Records of individual monitoring results.
Code of Federal Regulations, 2010 CFR
2010-01-01
... 10 Energy 1 2010-01-01 2010-01-01 false Records of individual monitoring results. 20.2106 Section 20.2106 Energy NUCLEAR REGULATORY COMMISSION STANDARDS FOR PROTECTION AGAINST RADIATION Records § 20... includes records required under the standards for protection against radiation in effect prior to January 1...
10 CFR 20.2106 - Records of individual monitoring results.
Code of Federal Regulations, 2013 CFR
2013-01-01
... 10 Energy 1 2013-01-01 2013-01-01 false Records of individual monitoring results. 20.2106 Section 20.2106 Energy NUCLEAR REGULATORY COMMISSION STANDARDS FOR PROTECTION AGAINST RADIATION Records § 20... includes records required under the standards for protection against radiation in effect prior to January 1...
10 CFR 20.2106 - Records of individual monitoring results.
Code of Federal Regulations, 2011 CFR
2011-01-01
... 10 Energy 1 2011-01-01 2011-01-01 false Records of individual monitoring results. 20.2106 Section 20.2106 Energy NUCLEAR REGULATORY COMMISSION STANDARDS FOR PROTECTION AGAINST RADIATION Records § 20... includes records required under the standards for protection against radiation in effect prior to January 1...
10 CFR 20.2106 - Records of individual monitoring results.
Code of Federal Regulations, 2014 CFR
2014-01-01
... 10 Energy 1 2014-01-01 2014-01-01 false Records of individual monitoring results. 20.2106 Section 20.2106 Energy NUCLEAR REGULATORY COMMISSION STANDARDS FOR PROTECTION AGAINST RADIATION Records § 20... includes records required under the standards for protection against radiation in effect prior to January 1...
10 CFR 20.2106 - Records of individual monitoring results.
Code of Federal Regulations, 2012 CFR
2012-01-01
... 10 Energy 1 2012-01-01 2012-01-01 false Records of individual monitoring results. 20.2106 Section 20.2106 Energy NUCLEAR REGULATORY COMMISSION STANDARDS FOR PROTECTION AGAINST RADIATION Records § 20... includes records required under the standards for protection against radiation in effect prior to January 1...
NASA Astrophysics Data System (ADS)
López-Comino, J. A.; Cesca, S.; Kriegerowski, M.; Heimann, S.; Dahm, T.; Mirek, J.; Lasocki, S.
2017-07-01
Ideally, the performance of a dedicated seismic monitoring installation should be assessed prior to the observation of target seismicity. This work is focused on a hydrofracking experiment monitored at Wysin, NE Poland. A microseismic synthetic catalogue is generated to assess the monitoring performance during the pre-operational phase, where seismic information only concerns the noise conditions and the potential background seismicity. Full waveform, accounting for the expected spatial, magnitude and focal mechanism distributions and a realistic local crustal model, are combined with real noise recording to produce either event based or continuous synthetic waveforms. The network detection performance is assessed in terms of the magnitude of completeness (Mc) through two different techniques. First, we use an amplitude threshold, taking into the ratio among the maximal amplitude of synthetic waveforms and station-dependent noise levels, for different values of signal-to-noise ratio. The detection probability at each station is estimated for the whole data set and extrapolated to a broader range of magnitude and distances. We estimate an Mc of about 0.55, when considering the distributed network, and can further decrease Mc to 0.45 using arrays techniques. The second approach, taking advantage on an automatic, coherence-based detection algorithm, can lower Mc to ∼ 0.1, at the cost of an increase of false detections. Mc experiences significant changes during day hours, in consequence of strongly varying noise conditions. Moreover, due to the radiation patterns and network geometry, double-couple like sources are better detected than tensile cracks, which may be induced during fracking.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lisenko, S A; Kugeiko, M M
We have solved the problem of layer-by-layer laser-light dosimetry in biological tissues and of selecting an individual therapeutic dose in laser therapy. A method is proposed for real-time monitoring of the radiation density in tissue layers in vivo, concentrations of its endogenous (natural) and exogenous (specially administered) chromophores, as well as in-depth distributions of the spectrum of light action on these chromophores. As the background information use is made of the spectrum of diffuse light reflected from a patient's tissue, measured by a fibre-optic spectrophotometer. The measured spectrum is quantitatively analysed by the method of approximating functions for fluxes ofmore » light multiply scattered in tissue and by a semi-analytical method for calculating the in-depth distribution of the light flux in a multi-layered medium. We have shown the possibility of employing the developed method for monitoring photosensitizer and oxyhaemoglobin concentrations in tissue, light power absorbed by chromophores in tissue layers at different depths and laser-induced changes in the tissue morphology (vascular volume content and ratios of various forms of haemoglobin) during photodynamic therapy. (biophotonics)« less
NASA Astrophysics Data System (ADS)
Muraro, S.; Battistoni, G.; Belcari, N.; Bisogni, M. G.; Camarlinghi, N.; Cristoforetti, L.; Del Guerra, A.; Ferrari, A.; Fracchiolla, F.; Morrocchi, M.; Righetto, R.; Sala, P.; Schwarz, M.; Sportelli, G.; Topi, A.; Rosso, V.
2017-12-01
Ion beam irradiations can deliver conformal dose distributions minimizing damage to healthy tissues thanks to their characteristic dose profiles. Nevertheless, the location of the Bragg peak can be affected by different sources of range uncertainties: a critical issue is the treatment verification. During the treatment delivery, nuclear interactions between the ions and the irradiated tissues generate β+ emitters: the detection of this activity signal can be used to perform the treatment monitoring if an expected activity distribution is available for comparison. Monte Carlo (MC) codes are widely used in the particle therapy community to evaluate the radiation transport and interaction with matter. In this work, FLUKA MC code was used to simulate the experimental conditions of irradiations performed at the Proton Therapy Center in Trento (IT). Several mono-energetic pencil beams were delivered on phantoms mimicking human tissues. The activity signals were acquired with a PET system (DoPET) based on two planar heads, and designed to be installed along the beam line to acquire data also during the irradiation. Different acquisitions are analyzed and compared with the MC predictions, with a special focus on validating the PET detectors response for activity range verification.
Electron energy distribution in a helium plasma created by nuclear radiations
NASA Technical Reports Server (NTRS)
Lo, R. H.; Miley, G. H.
1974-01-01
An integral balance technique for calculation of the electron energy distribution in a radiation-induced plasma is described. Results predict W-values reasonably well and compare favorably with more complicated Monte-Carlo calculations. The distribution found differs from that in a normal electrical discharge and is of interest in radiation-pumped laser research.
NASA Astrophysics Data System (ADS)
Oswald, Sandro M.; Pietsch, Helga; Baumgartner, Dietmar J.; Rieder, Harald E.
2016-04-01
A precise knowledge of the surface energy budget, which includes the solar and terrestrial radiation fluxes, is needed to accurately characterize the global energy balance which is largely determining Earth's climate. To this aim national and global monitoring networks for surface radiative fluxes have been established in recent decades. The most prominent among these networks is the so-called Baseline Surface Radiation Network (BSRN) operating under the auspices of the World Climate Research Programme (WCRP) (Ohmura et al., 1998). National monitoring networks such as the Austrian RADiation Monitoring Network (ARAD), which has been established in 2010 by a consortium of the Central Agency of Meteorology and Geodynamics (ZAMG), the University of Graz, the University of Innsbruck, and the University of Natural Resources and Applied Sciences, Vienna (BOKU), orient themselves on BSRN standards (McArthur, 2005). ARAD comprises to date five sites (Wien Hohe Warte, Graz/University, Innsbruck/University, Kanzelhöhe Observatory and Sonnblick (which is also a BSRN site)) and aims to provide long-term monitoring of radiation budget components at highest accuracy and to capture the spatial patterns of radiation climate in Austria (Olefs et al., 2015). Given the accuracy requirement for the local monitoring of radiative fluxes instrument offsets, triggered by meteorological factors and/or instrumentation, pose a major challenge in radiation monitoring. Within this study we investigate effects of ambient meteorology on the accuracy of radiation measurements performed with pyranometers contained in various heating/ventilation systems (HV-systems), all of which used in regular operation within the ARAD network. We focus particularly on instrument offsets observed following precipitation events. To quantify pyranometer responses to precipitation we performed a series of controlled laboratory experiments as well as targeted field campaigns in 2015 and 2016. Our results indicate that precipitation (as simulated by spray-tests or observed under ambient conditions) significantly affects the thermal environment of the instruments and thus their stability. Statistical analyses during nighttime conditions showed that precipitation triggers zero offsets of 4 W/m2 or more, depending on the HV-system and prevailing ambient conditions (i.e., air temperature, wind), indicating a clear exceedance of BSRN targets. References: McArthur L. J. B.: World Climate Research Programme-Baseline Surface Radiation Network (BSRN) - Operations Manual Version 2.1, Experimental Studies Division, Atmospheric Environment Service, Downsview, Ontario, Canada, 2005. Olefs M., Baumgartner D. J., Obleitner F., Bichler C., Foelsche U., Pietsch H., Rieder H. E., Weihs P., Geyer F., Haiden T., Schöner W.: The Austrian radiation monitoring network ARAD - best practice and added value, Atmospheric Measurement Techniques Discussions, 8: 10663-10710, 2015. Ohmura A., Dutton E. G., Forgan B., Frohlich C., Gilgen H., Hegner H., Heimo A., Stephens G. L., König-Langlo G., McArthur B., Müller G., Philipona R., Pinker R., Whitlock C. H., Dehne K., Wild M.: Baseline surface radiation network (bsrn/wcrp): new precision radiometry for climate research, Bulletin of the American Meteorological Society, 79(10): 2115-2136, 1998.
NASA Astrophysics Data System (ADS)
Watanabe, Takara; Enomoto, Ryoji; Muraishi, Hiroshi; Katagiri, Hideaki; Kagaya, Mika; Fukushi, Masahiro; Kano, Daisuke; Satoh, Wataru; Takeda, Tohoru; Tanaka, Manobu M.; Tanaka, Souichi; Uchida, Tomohisa; Wada, Kiyoto; Wakamatsu, Ryo
2018-02-01
We have developed an omnidirectional gamma-ray imaging Compton camera for environmental monitoring at low levels of radiation. The camera consisted of only six CsI(Tl) scintillator cubes of 3.5 cm, each of which was readout by super-bialkali photo-multiplier tubes (PMTs). Our camera enables the visualization of the position of gamma-ray sources in all directions (∼4π sr) over a wide energy range between 300 and 1400 keV. The angular resolution (σ) was found to be ∼11°, which was realized using an image-sharpening technique. A high detection efficiency of 18 cps/(µSv/h) for 511 keV (1.6 cps/MBq at 1 m) was achieved, indicating the capability of this camera to visualize hotspots in areas with low-radiation-level contamination from the order of µSv/h to natural background levels. Our proposed technique can be easily used as a low-radiation-level imaging monitor in radiation control areas, such as medical and accelerator facilities.
NASA Technical Reports Server (NTRS)
Gregory, J. C.
1986-01-01
Instrument design and data analysis expertise was provided in support of several space radiation monitoring programs. The Verification of Flight Instrumentation (VFI) program at NASA included both the Active Radiation Detector (ARD) and the Nuclear Radiation Monitor (NRM). Design, partial fabrication, calibration and partial data analysis capability to the ARD program was provided, as well as detector head design and fabrication, software development and partial data analysis capability to the NRM program. The ARD flew on Spacelab-1 in 1983, performed flawlessly and was returned to MSFC after flight with unchanged calibration factors. The NRM, flown on Spacelab-2 in 1985, also performed without fault, not only recording the ambient gamma ray background on the Spacelab, but also recording radiation events of astrophysical significance.
Kopp, Blaine S.; Nielsen, Martha; Glisic, Dejan; Neckles, Hilary A.
2009-01-01
This report documents results of pilot tests of a protocol for monitoring estuarine nutrient enrichment for the Vital Signs Monitoring Program of the National Park Service Northeast Coastal and Barrier Network. Data collected from four parks during protocol development in 2003-06 are presented: Gateway National Recreation Area, Colonial National Historic Park, Fire Island National Seashore, and Assateague Island National Seashore. The monitoring approach incorporates several spatial and temporal designs to address questions at a hierarchy of scales. Indicators of estuarine response to nutrient enrichment were sampled using a probability design within park estuaries during a late-summer index period. Monitoring variables consisted of dissolved-oxygen concentration, chlorophyll a concentration, water temperature, salinity, attenuation of downwelling photosynthetically available radiation (PAR), and turbidity. The statistical sampling design allowed the condition of unsampled locations to be inferred from the distribution of data from a set of randomly positioned "probability" stations. A subset of sampling stations was sampled repeatedly during the index period, and stations were not rerandomized in subsequent years. These "trend stations" allowed us to examine temporal variability within the index period, and to improve the sensitivity of the monitoring protocol to detecting change through time. Additionally, one index site in each park was equipped for continuous monitoring throughout the index period. Thus, the protocol includes elements of probabilistic and targeted spatial sampling, and the temporal intensity ranges from snapshot assessments to continuous monitoring.
Gold nanoshell thermal confinement of conformal laser thermal therapy in liver metastasis
NASA Astrophysics Data System (ADS)
Elliott, Andrew M.; Wang, James; Shetty, Anil M.; Schwartz, Jon; Hazle, John D.; Stafford, R. Jason
2008-02-01
Cooled fiber tip technology has significantly improved the volume coverage of laser induced thermal therapy (LITT), making LITT an attractive technology for the minimally invasive treatment of cancer. Gold coated nanoshells can be tuned to experience a plasmon resonance at a desired laser frequency, there introduction into the treatment region can greatly amplify the effectiveness of the thermal treatment. The goal is to conformaly heat the target, while sparing surrounding healthy tissue. To this end a treatment option that is self-confining to the target lesion is highly desirable. This can be achieved in the liver by allowing nanoshells to be taken up by the healthy tissue of the liver as part of their natural removal from the blood stream. The lesion is then incased inside the nanoshell laden tissue of the surrounding healthy tissue. When an interstitial laser probe is introduced into the center of the lesion the thermal radiation scatters outward until it interacts with and is absorbed by the nanoshells located around the lesion periphery. As the periphery heats it acts as secondary source of thermal radiation, sending heat back into lesion and giving rise to ablative temperatures within the lesion while sparing the surrounding tissue. In order to better monitor therapy and know when the target volume has been ablated, or exceeded, accurate knowledge is needed of both the spatial distribution of heating and the maximum temperature achieved. Magnetic resonance temperature imaging (MRTI) is capable of monitoring the spatiotemporal distribution of temperature in vivo[1]. Experiments have been performed in vitro using a dog liver containing nanoshells (concentration 860ppm) and a tissue like lesion phantom designed to have the optical properties of liver metastasis [2].
Optical sensing in laser machining
NASA Astrophysics Data System (ADS)
Smurov, Igor; Doubenskaia, Maria
2009-05-01
Optical monitoring of temperature evolution and temperature distribution in laser machining provides important information to optimise and to control technological process under study. The multi-wavelength pyrometer is used to measure brightness temperature under the pulsed action of Nd:YAG laser on stainless steel substrates. Specially developed "notch" filters (10-6 transparency at 1.06 μm wavelength) are applied to avoid the influence of laser radiation on temperature measurements. The true temperature is restored based on the method of multi-colour pyrometry. Temperature monitoring of the thin-walled gilded kovar boxes is applied to detect deviation of the welding seam from its optimum position. The pyrometers are used to control CO2-laser welding of steel and Ti plates: misalignment of the welded plates, variation of the welding geometry, internal defects, deviation of the laser beam trajectory from the junction, etc. The temperature profiles along and across the welding axis are measured by the 2D pyrometer. When using multi-component powder blends in laser cladding, for example metal matrix composite with ceramic reinforcement, one needs to control temperature of the melt to avoid thermal decomposition of certain compounds (as WC) and to assure melting of the base metal (as Co). Infra-red camera FLIR Phoenix RDAS provides detailed information on distribution of brightness temperature in laser cladding zone. CCD-camera based diagnostic system is used to measure particles-in-flight velocity and size distribution.
Characterizing Total Radiation Belt Electron Content Using Van Allen Probes Data
NASA Astrophysics Data System (ADS)
Huang, C. L.; Spence, H. E.; Boyd, A. J.; Jordan, A.; Paulson, K. W.; Zhang, J.; Blake, J. B.; Kletzing, C.
2014-12-01
The comprehensive particle and wave measurements of the Van Allen Probes enable us to monitor the entire radiation belt near the equator from L-shells of 2.5 to 6. Using the particle measurements, we create an improved, high-level quantity representing the entire outer belt. This quantity, the total radiation belt electron content (TRBEC), is the half-orbit sum of outer belt electrons over the radiation belt energy ranges of importance and all pitch angles using data from RBSP-ECT instrument on board both spacecraft. The goal is to characterize statistically the dynamics of the entire radiation belt by comparing TRBEC with solar wind parameters, magnetospheric waves, and electron seed population. When comparing TRBEC with solar wind velocity, our result shows a triangle-distribution similar to that which Reeves et al. (2011) found using geosynchronous electron flux. We also correlate TRBEC with other solar wind parameters to identify which solar wind conditions effectively enhance or deplete radiation belt electrons. In addition, plasma waves in the inner magnetosphere, via wave-particle interaction, are key elements affecting the dynamics of the radiation belt. Therefore, we compare TRBEC with integrated EMIC and chorus (upper and lower bands) wave power calculated from EMFISIS wave measurements to determine the relative importance between each wave-particle process. Finally, we demonstrate the ~100 keV seed population's characteristics that correspond to the MeV population enhancement. While the gross features of the two populations are similar, the MeV population's dynamics lag behind those of the seed population by 5 to 60 hours, which implies the acceleration or loss processes vary by event.
Chromatin Folding, Fragile Sites, and Chromosome Aberrations Induced by Low- and High- LET Radiation
NASA Technical Reports Server (NTRS)
Zhang, Ye; Cox, Bradley; Asaithamby, Aroumougame; Chen, David J.; Wu, Honglu
2013-01-01
We previously demonstrated non-random distributions of breaks involved in chromosome aberrations induced by low- and high-LET radiation. To investigate the factors contributing to the break point distribution in radiation-induced chromosome aberrations, human epithelial cells were fixed in G1 phase. Interphase chromosomes were hybridized with a multicolor banding in situ hybridization (mBAND) probe for chromosome 3 which distinguishes six regions of the chromosome in separate colors. After the images were captured with a laser scanning confocal microscope, the 3-dimensional structure of interphase chromosome 3 was reconstructed at multimega base pair scale. Specific locations of the chromosome, in interphase, were also analyzed with bacterial artificial chromosome (BAC) probes. Both mBAND and BAC studies revealed non-random folding of chromatin in interphase, and suggested association of interphase chromatin folding to the radiation-induced chromosome aberration hotspots. We further investigated the distribution of genes, as well as the distribution of breaks found in tumor cells. Comparisons of these distributions to the radiation hotspots showed that some of the radiation hotspots coincide with the frequent breaks found in solid tumors and with the fragile sites for other environmental toxins. Our results suggest that multiple factors, including the chromatin structure and the gene distribution, can contribute to radiation-induced chromosome aberrations.
Mirzabozorg, H.; Hariri-Ardebili, M. A.; Shirkhan, M.; Seyed-Kolbadi, S. M.
2014-01-01
The effect of solar radiation on thermal distribution in thin high arch dams is investigated. The differential equation governing thermal behavior of mass concrete in three-dimensional space is solved applying appropriate boundary conditions. Solar radiation is implemented considering the dam face direction relative to the sun, the slop relative to horizon, the region cloud cover, and the surrounding topography. It has been observed that solar radiation changes the surface temperature drastically and leads to nonuniform temperature distribution. Solar radiation effects should be considered in thermal transient analysis of thin arch dams. PMID:24695817
Mirzabozorg, H; Hariri-Ardebili, M A; Shirkhan, M; Seyed-Kolbadi, S M
2014-01-01
The effect of solar radiation on thermal distribution in thin high arch dams is investigated. The differential equation governing thermal behavior of mass concrete in three-dimensional space is solved applying appropriate boundary conditions. Solar radiation is implemented considering the dam face direction relative to the sun, the slop relative to horizon, the region cloud cover, and the surrounding topography. It has been observed that solar radiation changes the surface temperature drastically and leads to nonuniform temperature distribution. Solar radiation effects should be considered in thermal transient analysis of thin arch dams.
An educational distributed Cosmic Ray detector network based on ArduSiPM
NASA Astrophysics Data System (ADS)
Bocci, V.; Chiodi, G.; Fresch, P.; Iacoangeli, F.; Recchia, L.
2017-10-01
The advent of high performance microcontrollers equipped with analog and digital peripherals, makes the design of a complete particle detector and a relative acquisition system on a single microcontroller chip possible. The existence of a world wide data infrastructure such as the internet, allows for the conception of a distributed network of cheap detectors able to elaborate and send data as well as to respond to setting commands. The internet infrastructure enables the distribution of the absolute time, with precision of a few milliseconds, to all devices independently of their physical location, when the sky view is accessible it possible to use a GPS module to reach synchronization of tens of nanoseconds. These devices can be far apart from each other and their relative distance can range from a few meters to thousands of kilometers. This allows for the design of a crowdsourcing experiment of citizen science, based on the use of many small scintillation-based particle detectors to monitor the high energetic cosmic ray and the radiation environment.
Jones, Leslie A.; Muhlfeld, Clint C.; Hauer, F. Richard; F. Richard Hauer,; Lamberti, G.A.
2017-01-01
Stream temperature has direct and indirect effects on stream ecology and is critical in determining both abiotic and biotic system responses across a hierarchy of spatial and temporal scales. Temperature variation is primarily driven by solar radiation, while landscape topography, geology, and stream reach scale ecosystem processes contribute to local variability. Spatiotemporal heterogeneity in freshwater ecosystems influences habitat distributions, physiological functions, and phenology of all aquatic organisms. In this chapter we provide an overview of methods for monitoring stream temperature, characterization of thermal profiles, and modeling approaches to stream temperature prediction. Recent advances in temperature monitoring allow for more comprehensive studies of the underlying processes influencing annual variation of temperatures and how thermal variability may impact aquatic organisms at individual, population, and community based scales. Likewise, the development of spatially explicit predictive models provide a framework for simulating natural and anthropogenic effects on thermal regimes which is integral for sustainable management of freshwater systems.
NASA Astrophysics Data System (ADS)
Bager, T.; Casas-Cubillos, J.; Jeanmonod, N.
2006-04-01
The superconducting magnets of the Large Hadron Collider (LHC) will be cooled at 1.9 K by distributed cooling loops working with saturated two-phase superfluid helium flowing in 107 m long bayonet heat exchangers located in each magnet cold-mass cell. The temperature of the magnets could be difficult to control because of the large dynamic heat load variations. Therefore, it is foreseen to measure the heat exchangers pressure to feed the regulation loops with the corresponding saturation temperature. The required uncertainty of the sub-atmospheric saturation pressure measurement shall be of the same order of the one associated to the magnet thermometers, in pressure it translates as ±5 Pa at 1.6 kPa. The transducers shall be radiation hard as they will endure, in the worst case, doses up to 10 kGy and 1015 neutronsṡcm-2 over 10 years. The sensors under evaluation were installed underground in the dump section of the SPS accelerator with a radiation environment close to the one expected for the LHC. The monitoring equipment was installed in a remote radiation protected area. This paper presents the results of the radiation qualification campaign with emphasis on the reliability and accuracy of the pressure sensors under the test conditions.