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Heuristic techniques for maximum likelihood localization of radioactive sources via a sensor network

Nuclear Science and Techniques 2023年第8期34卷 174-193页

作者： Assem Abdelhakim Department of Radiation Engineering National Center for Radiation Research and TechnologyEgyptian Atomic Energy AuthorityCairo 11787Egypt

Maximum likelihood estimation(MLE)is an effective method for localizing radioactive sources in a given ***,it requires an exhaustive search for parameter estimation,which is *** this study,heuristic techniques were employed to search for radiation source parameters that provide the maximum likelihood by using a network of ***,the time consumption of MLE would be effectively ***,the radiation source was detected using the k-sigma ***,the MLE was applied for parameter estimation using the readings and positions of the detectors that have detected the radiation source.A comparative study was performed in which the estimation accuracy and time consump-tion of the MLE were evaluated for traditional methods and heuristic *** traditional MLE was performed via a grid search method using fixed and multiple ***,four commonly used heuristic algorithms were applied:the firefly algorithm(FFA),particle swarm optimization(PSO),ant colony optimization(ACO),and artificial bee colony(ABC).The experiment was conducted using real data collected by the Low Scatter Irradiator facility at the Savannah River National Laboratory as part of the Intelligent Radiation Sensing System *** comparative study showed that the estimation time was 3.27 s using fixed resolution MLE and 0.59 s using multi-resolution *** time consumption for the heuristic-based MLE was 0.75,0.03,0.02,and 0.059 s for FFA,PSO,ACO,and ABC,*** location estimation error was approximately 0.4 m using either the grid search-based MLE or the heuristic-based ***,heuristic-based MLE can provide comparable estimation accuracy through a less time-consuming process than traditional MLE.

关键词： Radioactive source Maximum likelihood estimation Multi-resolution MLE k-sigma Firefly algorithm Particle swarm optimization Ant colony optimization Artificial bee colony

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Simulation of ion beam extraction and focusing system

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Chinese Physics C 2011年第1期35卷 83-87页

作者： B.A.Soliman M.M.Abdelrahman A.G.Helal F.W.Abdelsalam Accelerators & Ion Sources Department Nuclear Research CenterEgyptian Atomic Energy Authority P.O.Box:13759 InchasAtomic EnergyCairoEgypt

The characteristics of ion beam extraction and focused to a volume as small as possible were investigated with the aid of computer code SIMION 3D version 7. This has been used to evaluate the extraction characteristics （accel-decel system） to generate an ion beam with low beam emittance and high brightness. The simulation process can provide a good study for optimizing the extraction and focusing system of the ion beam without any losses and transported to the required target. Also, a study of a simulation model for the extraction system of the ion source was used to describe the possible plasma boundary curvatures during the ion extraction that may be affected by the change in an extraction potential with a constant plasma density meniscus.

关键词： ion beam emittance plasma meniscus space charge argon ion trajectories

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Bayesian belief-based model for reliability improvement of the digital reactor protection system

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Nuclear Science and Techniques 2020年第10期31卷 55-73页

作者： Hanaa Torkey Amany S.Saber Mohamed K.Shaat Ayman El-Sayed Marwa A.Shouman Faculty of Electronic Engineering Menoufia UniversityCairoEgypt Nuclear Research Center Egyptian Atomic Energy AuthorityCairoEgypt

The digital reactor protection system(RPS)is one of the most important digital instrumentation and control(I&C)systems utilized in nuclear power plants(NPPs).It ensures a safe reactor trip when the safety-related parameters violate the operational limits and conditions of the *** high reliability and availability of digital RPS is essential to maintaining a high degree of reactor safety and cost *** main objective of this study is to develop a general methodology for improving the reliability of the RPS in NPP,based on a Bayesian Belief Network(BBN)*** structure of BBN models is based on the incorporation of failure probability and downtime of the RPS I&C *** architectures with dual-state nodes for the I&C components were developed for reliability-sensitive analysis and availability optimization of the RPS and to demonstrate the effect of I&C components on the failure of the entire system.A reliability framework clarified as a reliability block diagram transformed into a BBN representation was constructed for each architecture to identify which one will fit the required *** results showed that the highest availability obtained using the proposed method was *** are 120 experiments using two common component importance measures that are applied to define the impact of I&C modules,which revealed that some modules are more risky than others and have a larger effect on the failure of the digital RPS.

关键词： Nuclear power plants Reactor protection system Bayesian belief network

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Advantages and disadvantages of nuclear reactions used in reactors or cyclotrons,in addition to a theoretical study based on photodisintegration on natural indium for^(111)Ag production

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Nuclear Science and Techniques 2022年第2期33卷 1-13页

作者： Khaled M.El-Azony Nader M.A.Mohamed Dalal A.Aloraini Radioactive Isotopes and Generators Department Hot Labs.CenterEgyptian Atomic Energy AuthorityP.O.Box 13759CairoEgypt Reactors Department Egyptian Atomic Energy AuthorityP.O.Box 13759CairoEgypt Physics Department College of SciencePrincess Nourah Bint Abdulrahman UniversityRiyadhKingdom of Saudi Arabia

Production routes were recorded on available reactions for^(111)Ag production from nuclear reactors or cyclotrons using a natural palladium target based on^(110)Pd(n,γ)and^(110)pd(d,n)reactions,respectively.^(nat)Cd(γ,x)based on^(110)Cd(γ,p)has also been studied as a prospective reaction for the production of^(111)***,these nuclear reactions are difficult to utilize because,in some cases,they reduce the specific activity of^(111)*** is a consequence of the stable silver isotopes produced in high *** isotopes include^(107,109)Ag and,in other cases,the high impurity of silver radioisotopes,such as^(110)m,^(106)m,^(105)Ag,that are produced during parallel nuclear *** to a scarcity of data regarding the(γ,α)reaction,the gamma reaction on natural indium for^(111)Ag production based on the^(115)In(γ,α)reaction was *** ^(nat)In(γ,α)reaction satisfies the criteria as a possible reaction to produce^(111)Ag with a sufficient yield and purity as consequence of the high^(115)In(95.7%)abundance as an enriched form and a relatively soft background caused by the parallel nuclear reactions.

关键词： Silver-111 Nuclear data Natural cadmium Natural palladium Natural indium

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Preliminary evaluation of the radiotherapeutic efficacy of 131I-atorvastatin in rats with hepatocellular carcinoma

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Nuclear Science and Techniques 2020年第11期31卷 1-11页

作者： Nourihan S.Farrag Abeer M.Amin Labeled Compounds Department Hot Laboratories CentreEgyptian Atomic Energy Authority(EAEA)P.O.Box 13759CairoEgypt

As one of the most critical types of cancer,hepatocellular carcinoma(HCC)affects many people *** study demonstrated the prospective use of atorvastatin,a drug that inhibits the mevalonate pathway,causing hypolipidemia,as a carrier to deliver the iodine-131(131I)isotope to liver tissues for HCC *** atorvastatin radioiodination method was optimized for utilizing the131I *** radiochemical quality and the in vitro stability of the generated[131I]atorvastatin were *** addition,the biodistribution experiments of[131I]atorvastatin were evaluated in both normal and HCC-induced rat models.[131I]atorvastatin was produced at a maximum radiochemical yield of 86.7±0.49%.The[131I]atorvastatin solution purified via high-performance liquid chromatography showed good in vitro stability for 12 h after *** analyses revealed remarkable liver targeting capacity of[131I]atorvastatin and good localization of131I in liver ***,the encouraging biochemical profile and histopathologicalfindings have been reported,and preliminary investigations on the possible use of[131I]atorvastatin as a radiotracer and its impact on HCC radiotherapy in rats show promise.

关键词： Hepatocellular carcinoma [131I]Atorvastatin Biodistribution Radiotherapy

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Employing adaptive fuzzy computing for RCP intelligent control and fault diagnosis

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Nuclear Science and Techniques 2023年第9期34卷 82-93页

作者： Ashraf Aboshosha Hisham A.Hamad Rad.Eng.Department NCRRTEgyptian Atomic Energy Authority(EAEA)CairoEgypt Electronics Technology Department Faculty of Technology and EducationHelwan UniversityCairoEgypt

Loss of coolant accident(LOCA),loss of fluid accident(LOFA),and loss of vacuum accident(LOVA)are the most severe accidents that can occur in nuclear power reactors(NPRs).These accidents occur when the reactor loses its cooling media,leading to uncontrolled chain reactions akin to a nuclear *** article is focused on exploring methods to prevent such accidents and ensure that the reactor cooling system remains fully *** reactor coolant pump(RCP)has a pivotal role in facilitating heat exchange between the primary cycle,which is connected to the reactor core,and the secondary cycle associated with the steam ***,the RCP is integral to preventing catastrophic events such as LOCA,LOFA,and LOVA *** this study,we discuss the most critical aspects related to the RCP,specifically focusing on RCP control and RCP fault *** AI-based adaptive fuzzy method is used to regulate the RCP’s speed and torque,whereas the neural fault diagnosis system(NFDS)is implemented for alarm signaling and fault diagnosis in nuclear *** address the limitations of linguistic and statistical intelligence approaches,an integration of the statistical approach with fuzzy logic has been *** integrated system leverages the strengths of both *** fuzzy control was applied to the VVER 1200 NPR-RCP induction motor,and the NFDS was implemented on the Kori-2 NPR-RCP.

关键词： Nuclear power plant(NPP) Reactor coolant pump Fault diagnosis Reactor passive safety Neural network Adaptive fuzzy

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Persea americana attenuates inflammatory response associated with hyperlipidemia in ovariectomized and irradiated rats by regulating MMP-3/TIMP-1 levels

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Asian Pacific Journal of Tropical Biomedicine 2022年第9期12卷 374-382页

作者： Dina F.Elmaghraby Fatma A.M.Salem Esraa S.A.Ahmed Department of Health Radiation Research National Center for Radiation Research and TechnologyEgyptian Atomic Energy AuthorityCairoEgypt Department of Chemistry Faculty of ScienceHelwan UniversityCairoEgypt Radiation Biology Research National Center for Radiation Research and TechnologyEgyptian Atomic Energy AuthorityCairoEgypt

Objective:To explore the effect of Persea americana supplementation on inflammation,oxidative stress,and lipid profiles in ovariectomized rats fed with a high-fat diet and exposed to ***:The control group was sham operated,while groups 2-5 were ovariectomized and fed a high-fat *** 4 and 5 were exposed toγ-radiation(1 Gy/week for 5 weeks)after *** 3 and 5 were treated with 1 mL/250 g/day of Persea americana for one *** levels of estrogen,alanine aminotransferase,aspartate aminotransferase,cholesterol,triglycerides and lipoproteins were ***,hepatic oxidative stress,inflammatory and fibrogenic markers were ***:Persea americana treatment reduced the oxidative stress markers as well as the levels of triglyceride,total cholesterol,and low-density lipoprotein cholesterol,which in turn lowered hepatic fat ***,it suppressed hepatic inflammatory mediators(interleukin-6,tumor necrosis factor-α,and C-reactive protein)and downregulated pro-fibrogenic markers(transforming growth factor-βand tissue inhibitor of metalloproteinase-1).Conclusions:Persea americana provides protection against ovariectomy,and gamma radiation-mediated hepatic inflammation not only through its antioxidant,anti-inflammatory,lipid-lowering effect but also by modulating the fibrogenic markers.

关键词： Persea americana γ-Radiation Postmenopausal Oxidative stress Lipid Ovariectomy Hepatic inflammation Fibrogenic Rat

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Multiphysics simulation of VVER-1200 fuel performance during normal operating conditions

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Nuclear Science and Techniques 2023年第2期34卷 139-152页

作者： Khaled M.Yassin Mohamed H.Hassan Mohammad M.Ghoneim Mostafa S.Elkolil Adel Alyan Said A.Agamy Nuclear Research Center Egyptian Atomic Energy AuthorityAbo Zaabal 13759CairoEgypt Department of Nuclear and Radiological Engineering Faculty of EngineeringAlexandria UniversityAlexandria 21544Egypt Faculty of Engineering Egyptian Russian UniversityBadr 11829Egypt

Nuclear fuel performance modeling and simulation are critical tasks for nuclear fuel design optimization and safety analysis under normal and transient *** performance is a complicated phenomenon that involves thermal,mechanical,and irradiation mechanisms and requires special multiphysics *** this study,a fuel performance model was developed using the COMSOL Multiphysics *** modeling was performed for a 2D axis-symmetric geometry of a UO2fuel pellet in the E110 clad for VVER-1200 *** modeling considers all relevant phenomena,including heat generation and conduction,gap heat transfer,elastic strain,mechanical contact,thermal expansion,grain growth,densification,fission gas generation and release,fission product swelling,gap/plenum pressure,and cladding thermal and irradiation *** model was validated using a code-to-code evaluation of the fuel pellet centerline and surface temperatures in the case of constant power,in addition to validation of fission gas release(FGR)*** prediction proved that the model could perform according to previously published VVER nuclear fuel performance parameters.A sensitivity study was also conducted to assess the effects of uncertainty on some of the model *** model was then used to predict the VVER-1200 fuel performance parameters as a function of burnup,including the temperature profiles,gap width,fission gas release,and plenum pressure.A compilation of related material and thermomechanical models was conducted and included in the modeling to allow the user to investigate different material/performance *** the model was developed for normal operating conditions,it can be modified to include off-normal operating conditions.

关键词： VVER-1200 Fuel performance COMSOL code Zr-1%Nb cladding UO2 fuel rod

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Flavone improves liver damage in nicotine-exposed rats via the Nrf2/HO-1 pathway

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Asian Pacific Journal of Tropical Biomedicine 2024年第8期14卷 341-349页

作者： Nora A.Elsayed Fatma SM Moawed Esraa SA Ahmed Ahmed Hammad Omayma AR Abo-Zaid Biochemistry and Molecular Biology Department Faculty of Vet.Med.Benha UniversityBenha cityEgypt Health Radiation Research National Center for Radiation Research and TechnologyEgyptian Atomic Energy AuthorityCairoEgypt Radiation Biology Department National Center for Radiation Research and TechnologyEgyptian Atomic Energy AuthorityCairoEgypt

Objective:To assess the hepatoprotective effects of flavone on nicotine-induced liver ***:Thirty-six rats were allocated into six groups:the control group,the nicotine group,the flavone alone groups(10 and 25 mg/kg/body weight),and the nicotine groups treated with flavone(10 and 25 mg/kg/body weight).Liver function,oxidative stress,Nrf2 pathway(HO-1,Nrf2,and Keap-1),and inflammatory markers(IL-17,TNF-α,and NF-κB)were ***,a histopathological examination of liver tissues was ***:Nicotine increased liver damage,inflammation,and oxidative ***,flavone suppressed nicotine-induced liver enzymes,oxidative stress,and inflammation,as manifested by increased antioxidants and decreased malondialdehyde level,liver enzymatic activities,and inflammatory ***(10 and 25 mg/kg/body weight)also reduced the level of Keap-1 and increased HO-1 and Nrf2 levels in the liver of nicotine-exposed ***:Flavone has hepatoprotective properties and may slow the progression of liver injury by reducing oxidative stress,liver enzymes,and inflammation possibly via the Nrf2 pathway.

关键词： Flavone Nicotine Liver Nrf2 HO-1 NF-κB

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Impact of wastewater reuse on cobalt status in egyptian environment

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Journal of Environmental Sciences 2003年第3期15卷 388-395页

作者： M.F. Abdel-Sabour Soil and Water Research Department Nuclear Research Center Atomic Energy Authority

Cobalt is used in the manufacture of alloys, catalysts in the petroleum industry, catalytic converters, and paint pigments. Thus the potential for Co releases into the environment is highly increased. Use of waste sludges and sewage effluent to fertilize and irrigate soils has also increased soil Co concentrations. Total cobalt contents of alluvial delta soil of Egypt show considerable variation ranging from 13.1 to 64.7 ppm. The impact of either wastewater irrigation or industrial activities on soil total Co was obvious due to accumulation of organic matter and solid waste in the surface soil samples. Food crops and vegetables should not be grown on soil highly contaminated by Co. It is noteworthy that the delayed neutron activation analysis(DNAA) technique could be used successfully for total Co determination due to its high sensitivity. It is quit clearly that dust samples of Cairo City contains higher Co level, as compared to Suez Canal Region(Ismailia, Port Said and El-Suez cities). The high values in Cairo City may be due to the existence of industries around the city and the intensive traffic. To minimize Co environmental hazards, waste effluents should be treated on site. Thus, levels of potentially toxic Co needs to be continuously monitored and should be removed during several treatment processes before the disposal of these wastes.

关键词： cobalt environment Egypt

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