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CrossRef Open Access 2025
Beyond the manual: A sociotechnical resilience assessment of South Korea's radiological emergency preparedness system

Han Joo, Joo Moon

Following the Fukushima nuclear power plant accident, the Republic of Korea has significantly enhanced its radiological emergency preparedness system. However, a deep-seated evaluation of the system's practical effectiveness remains insufficient. This study applies the framework of resilience engineering to systematically evaluate the Emergency Response Manuals of the Republic of Korea's central and local governments, with the aim of identifying the system's fundamental strengths and weaknesses. The analysis reveals notable strengths in technical and quantitative domains, particularly in monitoring and communication mechanisms. However, it also exposes critical shortcomings in complex and dynamic capabilities, such as adaptive scenario-based response strategies, long-term recovery planning, and human resource management. Notably, disparities in response capabilities among local governments, stemming from differences in budget and engagement, undermine the system's overall effectiveness. This study argues that these flaws are not merely procedural gaps. They are rooted in a performance paradox and a lack of anticipatory governance deeply embedded in Korea's public administration practices. Accordingly, the core contribution of this research lies in identification of systemic constraints in adaptive capacity and long-term recovery planning within the national disaster governance model. The improvements derived from this study should be integrated into the radiological emergency preparedness system to ensure thorough preparedness and effective management of potential nuclear disasters.

CrossRef Open Access 2022
Development of nuclear radiation monitors for radiation early warning systems

Vladimirs Gostilo, Andrey Vlasenko, Vasily Litvinsky et al.

The results of the development of modern precision monitors of alpha, beta and gamma ray radiation for setting up early warning systems for radioactive contamination in the atmosphere and rapid assessment of emerging threats, are presented. Proportional counters, scintillation SrI (Eu) crystals and semiconductor Si, CdZnTe, and HPGe detectors are used for 2 the development. The designed monitors provide information both on dose rate values in real time and on the activity of specific radionuclides. The software controls the measurement mode, as well as diagnoses the condition of the monitors themselves.

CrossRef Open Access 2021
Influence of gamma radiation on Josephson junction

Nenad Kartalovic, Saska Djekic, Sasa Djekic et al.

Quantum mechanics consideration, supported by a concrete example, yielded standard sources of direct voltage measured by frequency (which is the most accurate measurable physical quantity) and extremely sensitive instrument for measuring magnetic induction SQUID (which is an acronym based on the term Superconducting Quantum Interference Device). The possibility of these measurements is based on the Josephson junction. In this paper, the influence of gamma radiation on the measurement uncertainty Type A, of a commercial Josephson compound, is investigated. The conclusion is that both dynamic gamma radiation and the dose of gamma radiation, under the conditions of the experiment, have a negligible effect on the measurement uncertainty of the Josephson junction. Based on the obtained result, it was concluded that in the primary metrological conditions, the measurement uncertainty type A of the Josephson junction is negligible, i. e., that the secondary cosmic radiation does not affect the standard of the DC voltage source.

CrossRef Open Access 2021
Calibration and measurement of X-ray personal dose equivalent with a Hp(10) ionization chamber

Yang Xu, Rui Zhao

The value of the personal dose equivalent at a 10 mm depth is to characterize the energy deposition of strong penetrating radiation in the human body and is derived by measurement of air kerma and application of conversion coefficients from the ISO report. However, the conversion coefficients depend strongly on the photon energy and angles of incidence for low-energy photons. In order to overcome the problem that the conversion coefficient of low energy rays changes greatly due to the small change of energy, a secondary standard ionization chamber was used to measure the personal dose equivalent directly. A matched reference field was established with 20-250 kV X-rays and correction factors with the Hp (10) chamber were calculated under these radiation qualities with different angles of incidence. The results showed that the differences were almost 22.7 % of correction factors for the low energy photons at angles of incidence 0?. With the conversion coefficient recommended in ISO 4037-3-2019, the performance of the chamber response with respect to Hp (10) in the energy range from 33 keV to 208 keV was within about 10 %, and in the energy range from 12 keV to 208 keV and for angles of incidence between 0? and 75? was within about ?19 %.

CrossRef Open Access 2021
Dual number automatic differentiation as applied to two-group cross-section uncertainty propagation

Pavel Bokov, Danniell Botes, Suzanne Groenewald

This work addresses the problem of propagating uncertainty from group-wise neutron cross-sections to the results of neutronics diffusion calculations. Automatic differentiation based on dual number arithmetic was applied to uncertainty propagation in the framework of local sensitivity analysis. As an illustration, we consider a two-group diffusion problem in an infinite medium, which has a solution in a closed form. We employ automatic differentiation in conjunction with the sandwich formula for uncertainty propagation in three ways. Firstly, by evaluating the analytical expression for the multiplication factor using dual number arithmetic. Then, by solving the diffusion problem with the power iteration algorithm and the algebra of dual matrices. Finally, automatic differentiation is used to calculate the partial derivatives of the production and loss operators in the perturbation formula from the adjoint-weighted technique. The numerical solution of the diffusion problem is verified against the analytical formulas and the results of the uncertainty calculations are compared with those from the global sensitivity analysis approach. The uncertainty values obtained in this work differ from values given in the literature by less than 1?10?5.

CrossRef Open Access 2020
Time domain solution of electromagnetic radiation model of the grounding system excited by pulse current

Nedis Dautbasic, Adnan Mujezinovic

This paper deals with an advanced electromagnetic radiation approach for analyzing the time-domain performance of grounding systems under pulse excitation currents. The model of the grounding systems presented within this paper is based on the homogeneous Pocklington integro-differential equation for the calculation of the current distribution on the grounding system and Lorentz gauge condition which is used for the grounding system transient voltage calculation. For the solution of the Pocklington integro-differential equation, the indirect boundary element method and marching on-in time method are used. Fur- thermore, the solution technique for the calculation of the grounding system transient voltage is presented. The numerical model for the calculation of the grounding system transients was verified by comparing it with onsite measurement results.

CrossRef Open Access 2018
An experimental search for a correlation between outdoor 222Rn concentration and 210Pb activity in air particulate samples

Elio Tomarchio

This work was aimed to search for a correlation between outdoor 222Rn air concentration and 210Pb activity in particulate samples collected on a filter. The existence of a correlation could support the hypothesis that both 222Rn and its long-lived product 210Pb are embedded into the same air masses and undergo the same air transport phenomena. Lead-210 activity was determined by means of gamma ray spectrometric measurement carried out a few days after the sampling whereas 222Rn concentration was measured through a commercial monitor. Experimental tests allowed to obtain a weak correlation between 222Rn and 210Pb air concentration as a preliminary result due to high uncertainties of outdoor 222Rn concentration measurements.

CrossRef Open Access 2017
Local probability of indoor radon concentration to exceed the threshold estimated from geogenic radon potential

Peter Bossew

Indoor radon has been recognized as an important air pollutant. Based on epidemiological evidence, it is estimated that indoor radon is the second cause of lung cancer after smoking. As a consequence, one tries to limit exposure through regulations concerning the remediation of the existing and prevention of future exposure. In this context, an essential task is the delineation of areas in which it can be expected with certain confidence that time-averaged indoor radon concentrations in dwellings and workplaces exceed the reference level. These are called radon priority areas to denote that these are areas in which remedial and preventive action has to be implemented with priority. There are different definitions of radon priority areas and different methods to estimate them from data. In Germany, the current approach uses the geogenic radon potential as the predictor. However, legal reference levels pertain to indoor radon concentration, not to the geogenic radon potential. One therefore has to identify derived reference levels for geogenic radon potential through statistical association of both quantities. This paper presents a method to derive the local probability that indoor radon concentration exceeds a threshold, given the local geogenic radon potential. The relationship can be used to derive geogenic radon potential reference levels which in turn serve to define radon priority areas.

CrossRef Open Access 2016
Studies on neutron and photon kerma parameters for human body organs

Vishvanath Singh, Nagappa Badiger, Rene Vega-Carrillo

A study on neutron kerma factors and photon air-kerma for human organs is presented for neutron energy range 2.53?10-8 MeV to 29 MeV and photon energy range 1 keV to 20 MeV. The human organs water equivalence for photon and neutron, is also presented. The ratio of the mass-energy absorption coefficients of human organs to water was found constant and unity above 100 keV, whereas there was a large difference for energies below 100 keV. The neutron kerma factors of human organs and water are found of same order of magnitude whereas differs for air. The neutron kerma factors of human organs and tissue substitutes were found to be equal to water for neutron energies between 63 eV and 200 keV. The skeleton-cortical bone was found to be away from water equivalence for low-energy photons and high-energy neutrons.

CrossRef Open Access 2016
Insulation co-ordination and the enlargement law for the GM counter tube

Edin Dolicanin, Irfan Fetahovic, Djordje Lazarevic et al.

In this paper we analyze application of contemporary methods of insulation co-ordination and the enlargement law in designing a GM counting tube. It has been shown that by applying insulation co-ordination methods the counting tube can be optimally dimensioned. The application of the enlargement law was demonstrated in generalizing the results of test obtained by the GM tube to those obtained by the counting tube with m-times greater dimensions. The investigations were conducted both theoretically and by experiment. Using theoretical analysis, we derived the expressions that may be applied if a performance function of a random variable breakdown voltage is known. The experiments were conducted on a GM counter model under well controlled laboratory conditions.

CrossRef Open Access 2015
Development of portable HPGe spectrometer for in situ measurements

Artjoms Kail, Matthias Kaiser, Sergey Kim et al.

In situ applications require a very high level of portability of high-resolution spectrometric equipment. Usage of HPGe detectors for radioactivity measurements in the environment or for nuclear safeguard applications, to combat illicit trafficking of nuclear materials or uranium and plutonium monitoring in nuclear wastes, has become a norm in the recent years. Portable HPGe-based radionuclide spectrometer with electrical cooling has lately appeared on the market for in situ applications. At the same time deterioration of energy resolution associated with vibrations produced by cryocooler or high weight of the instrument, short time of autonomous operation and high price of these spectrometers are limiting their usage in many cases. In this paper we present development results of ultra compact hand held all-in-one spectrometer for in situ measurements based on HPGe detector cooled by liquid nitrogen without listing the above disadvantages.

CrossRef Open Access 2012
Biomonitoring of 137Cs, 40K, 232Th, and 238U using oak bark in Belgrade forest, Istanbul, Turkey

Onder Kilic

In the present study, the bark of oak trees (Quercus petraea Liebl.) was collected from Belgrade Forest northwest of Istanbul for determination of 137Cs, 40K, 232Th, and 238U activity. A gamma spectrometer equipped with high-purity germanium detector was used for radioactivity measurement. Bark samples were collected from the northern and southern sides of trees at a height of 1.5 m above the ground in order to see the effects of rainfall and wind; and they were also collected from the northern side at a height of 0.5 m above the ground to assess the effect of soil splash. The activity concentrations of 137Cs, 40K, 232Th, and 238U in the bark samples were found to vary in the range of 1.40-27.50, 45.0-221.2, 0.92-9.64, and 4.04-36.10 Bq/kg, respectively. The elevated activity of 238U in bark samples could be attributed to a large amount of coal combustion in the region until the 1990s. According to one-way ANOVA, a significant difference was not found in bark samples collected at a height of 0.5 m and 1.5 m above the ground in terms of radionuclide activity. There was also no significant variation regarding radionuclide accumulation between northern and southern sides.

CrossRef Open Access 2009
A new simulation model for calculating the internal exposure of some radionuclides

Ayman Mahrous, Abdel Moneim, Nadia Helal et al.

A new model based on a series of mathematical functions for estimating excretion rates following the intake of nine different radionuclides is presented in this work. The radionuclides under investigation are: cobalt, iodine, cesium, strontium, ruthenium, radium, thorium, plutonium, and uranium. The committed effective dose has been calculated by our model so as to obtain the urinary and faecal excretion rates for each radionuclide. The said model is further validated by a comparison with the widely spread Mondal software and a simulation program. The results obtained show a harmony between the Mondal package and the model we have constructed.

CrossRef Open Access 2008
Influence of radiation energy and angle of incidence on the uncertainty in measurements by GM counters

Koviljka Stankovic, Milos Vujisic

This paper discusses the influence of radiation energy and angle of incidence as possible sources of uncertainties in measurements performed by GM counters. Based on the detection efficiency of GM counters, it has been concluded that the energy of incident radiation does not contribute to the overall uncertainty. The angle of incident radiation does contribute to overall uncertainty, but only in the case of gamma radiation detection. In that case, the uncertainty should be determined by using geometrical probability.

CrossRef Open Access 2007
Spectral albedo of photons of initial energies below 100 keV

Srpko Markovic, Rodoljub Simovic, Vladan Ljubenov et al.

This paper shows the results of Monte Carlo simulations of the photon reflection from homogenous plates of the shield materials made of water, aluminum, and iron. Perpendicular incidence of a monoenergetic photon beam of the initial energy of 20 keV up to 100 keV is considered. The numerical experiments were performed using the verified Monte Carlo programs MCNP-4C, FOTELP-2K3, and PENELOPE-2005. As the result, the values of difference number albedo distributed in ten even intervals according to the energy and nine even intervals according to the polar angle of reflected photons were obtained. Out of these data, the spectral albedo coefficients for all three materials and three initial photon energies of 40 keV, 60 keV, and 100 keV were calculated, graphically presented, and analyzed. The values of the spectral albedo determined on the basis of MCNP-4C code were compared to the results of the early simulations of the photon reflection performed in Russia and in the USA. Also, with the help of MCNP-4C program, the yield of fluorescent photons to the spectrum of the reflected radiation was registered, which can be seen in the graphs in the form of the peak at the energy of 7.112 keV only at the shielding plates made of iron.

CrossRef 2025
Privacy-Enhancing Technologies et machine learning

Iago Baumann

This article examines the main privacy-enhancing technologies (PETs) applied to machine learning – anonymisation, pseudonymisation, differential privacy, federated learning, and homomorphic encryption – and assesses their impact on data protection. By combining a technical approach with legal analysis, it shows how these tools can support compliance with the Swiss DPA and the GDPR, particularly through the principle of data protection by design. While it remains difficult to provide definitive answers de lege lata, the study highlights concrete solutions available to data controllers, while also raising key debates on the legal framework needed to govern the development of AI.

CrossRef 2025
Die Sonderabgabe auf Vermögenswerten

Andjela Nikitic

The special levy on assets (Art. 86 Asylum Act) serves to reimburse state expenditure incurred by asylum seekers and persons seeking protection. Despite its earmarking and time limitation, there is no individually attributable state benefit. Therefore, this is not a casual levy, but a cost allocation tax. Its collection would require an explicit constitutional authority to levy taxes, which does not exist in the present case. Furthermore, the legals basis does not satisfy the principle of legality.

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