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EJUSTCO:Monte Carlo radiation transport code hybrid with ANN model for gamma-ray shielding simulation

Nuclear Science and Techniques 2023年第9期34卷 155-176页

作者： Joseph Konadu Boahen Ahmed S.G.Khalil mohsen a.hassan Samir A.Elsagheer Mohamed Materials Science and Engineering Department School of Innovative Design EngineeringEgypt-Japan University of Science and Technology(E-JUST)179New Borg El-Arab CityEgypt Physics Department Environmental and Smart Technology GroupFaculty of ScienceFayoum UniversityFayoum 63514Egypt Faculty of Engineering Aswan UniversityAswanEgypt

Gamma ray shielding is essential to ensure the safety of personnel and equipment in facilities and environments where radiation exists.The Monte Carlo technique is vital for analyzing the gamma-ray shielding capabilities of materials.In this study,a simple Monte Carlo code,EJUSTCO,is developed to cd simulate gamma radiation transport in shielding materials for academic purposes.The code considers the photoelectric effect,Compton(incoherent)scattering,pair production,and photon annihilation as the dominant interaction mechanisms in the gamma radiation shielding problem.Variance reduction techniques,such as the Russian roulette,survival weighting,and exponential transformation,are incorporated into the code to improve computational efficiency.Predicting the exponential transformation parameter typically requires trial and error as well as expertise.Herein,a deep learning neural network is proposed as a viable method for predicting this parameter for the first time.The model achieves an MSE of 0.00076752 and an R-value of 0.99998.The exposure buildup factors and radiation dose rates due to the passage of gamma radiation with different source energies and varying thicknesses of lead,water,iron,concrete,and aluminum in single-,double-,and triple-layer material systems are validated by comparing the results with those of MCNP,ESG,ANS-6.4.3,MCBLD,MONTEREY MARK(M),PENELOPE,and experiments.Average errors of 5.6%,2.75%,and 10%are achieved for the exposure buildup factor in single-,double-,and triple-layer materials,respectively.A significant parameter that is not considered in similar studies is the gamma ray albedo.In the EJUSTCO code,the total number and energy albedos have been computed.The results are compared with those of MCNP,FOTELP,and PENELOPE.In general,the EJUSTCO-developed code can be employed to assess the performance of radiation shielding materials because the validation results are consistent with theoretical,experimental,and literary results.

关键词： Monte Carlo Gamma rays Shielding Artificial neural network Simulation

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Application of artificial intelligence techniques in modeling attenuation behavior of ionization radiation: a review

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Radiation Detection Technology and Methods 2023年第1期7卷 56-83页

作者： Joseph Konadu Boahen Samir A.Elsagheer Mohamed Ahmed S.G.Khalil mohsen a.hassan Materials Science and Engineering Department School of Innovative Design EngineeringEgypt-Japan University of Science and Technology(E-JUST)P.O.Box 179New Borg El-Arab CityEgypt Computer Science and Information Technology Programs Egypt-Japan University of Science and Technology(E-JUST)AlexandriaEgypt Faculty of Engineering Aswan UniversityAswanEgypt Institute of Basic and Applied Science Egypt-Japan University of Science and Technology(E-JUST)179 New Borg El-Arab CityAlexandriaEgypt Environmental and Smart Technology Group Faculty of ScienceFayoum UniversityFayoum63514Egypt

Introduction Shielding of ionizing radiations,which are gamma rays,neutrons,and X-rays,can be achieved by attenuating its intensity using different materials.Protection is therefore crucial in ensuring the safety of lives and essential equipment in areas such as nuclear power plants,radiotherapy facilities,space exploration,and others.Artificial Intelligent technologies have become desirable in modeling shielding materials’attenuation behavior due to their unique advantages.Objective The overview aims to present the recent application of AI technologies in modeling the radiation attenuation behavior of materials.Methods A total of 41 relevant articles were obtained using Scopus and web of science databases.The search was restricted to articles and conference papers published within the last two decades.Results From the overview,it was realized that AI techniques can predict the attenuation properties of shielding materials and optimize the shield design.The methods can be grouped into predictive models which are:fuzzy logic,Support Vector Regression,Neural Networks,and optimization models which include Genetic algorithms,Ant Colony,and Particle Swarm Optimization.Neural networks are the most robust and widely used technique.The predictive models are used in predicting parameters such as attenuation coefficient,buildup factor,shield thickness,and radiation dose rates,whiles the optimization techniques are employed in single and multi-objective attenuator designs.Conclusion In the overview,the accuracies and complexities of the various AI techniques have been discussed giving insight into their prospects.The AI techniques are easy to model compared to conventional methods and can save computational time when coupled with conventional statistical and deterministic models or employed as a standalone technique.

关键词： Ionization radiation Attenuation behavior Artificial intelligence Modeling

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The effectiveness of physical activity interventions on blood pressure in children and adolescents:A systematic review and network meta-analysis

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Journal of Sport and Health Science 2024年第5期13卷 699-708页

作者： Mohamed a.hassan Wanjiang Zhou Mingyi Ye Hui He Zan Gao School of Kinesiology University of Minnesota-Twin CitiesMinneapolisMN 55455USA Department of Methods and Curriculum Physical Education College for MenHelwan UniversityCairo 12552Egypt China Institute of Sport and Health Science Beijing Sport UniversityBeijing 100084China Department of Kinesiology Recreationand Sport StudiesUniversity of TennesseeKnoxvilleTN 37996USA

Background:High blood pressure(BP)is a major contributor to mortality and cardiovascular diseases.Despite the known benefits of exercise for reducing BP,it is crucial to identify the most effective physical activity(PA)intervention.This systematic review and network meta-analysis(NMA)aimed to evaluate the available evidence on the effectiveness of various PA interventions for reducing BP and to determine their hierarchy based on their impact on BP.Methods:A search of PubMed,SPORTDiscus,PsycINFO,Web of Science,CINAHL,Cochrane,and Eric databases was conducted up to December 2022 for this systematic review and NMA.Randomized controlled trials and quasi-experimental studies targeting healthy children and adolescents aged 6-12 years old were included in this study.Only studies that compared controlled and intervention groups using PA or exercise as the major influence were included.We followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses(PRISMA)guidelines.Three independent investigators performed the literature screening,data extraction,and risk of bias assessment.We used Bayesian arm-based NMA to synthesize the data.The primary outcomes were systolic BP and diastolic BP.We calculated the mean differences(MDs)in systolic BP and diastolic BP before and after treatment.Mean treatment differences were estimated using NMA and random-effect models.Results:We synthesized 27 studies involving 15,220 children and adolescents.PA combined with nutrition and behavior change was the most effective intervention for reducing both systolic BP and diastolic BP(MD=-8.64,95%credible interval(95%CI):-11.44 to-5.84;MD=-6.75,95%CI:-10.44 to-3.11),followed by interventions with multiple components(MD=-1.39,95%CI:-1.94 to-0.84;MD=-2.54,95%CI:-4.89 to-0.29).Conclusion:Our findings suggest that PA interventions incorporating nutrition and behavior change,followed by interventions with multiple components,are most effective for reducing both systolic BP and diastolic BP in children and adolescents.

关键词： Children Diastolic blood pressure Physical activity Systolic blood pressure

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Kaoline-based catalyst for a high stability desulfurization of sour heavy naphtha in a three-phase oscillatory baffled reactor

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Particuology 2024年第1期84卷 249-260页

作者： hassan M.Hmood Saba A.Gheni Safaa M.R.Ahmed Mudheher M.Ali Hamid Yonis Saleh Mohammed H.Mohammed Awad E.Mohammed Marwan A.Mahomood Hiba R.Mohammed Ahmed a.hassan Adam Harvey North Refineries Company Ministry of OilIraq Chemical Engineering Department Tikrit UniversityIraq Ministry of Oil Iraq AL-Hawija Technical Institute Northern Technical UniversityMoselIraq School of Engineering Newcastle UniversityUK

To meet the rapidly increasing demand for energy and the dramatic depletion of conventional crude oil,it is imperative to utilize sour naphtha.With no coke being produced,oxidative desulfurization(ODS)of naphtha lowers its sulfur content and average molecular weight.In this article,we outline a method for heavy naphtha non-extractive ODS using a very stable catalyst.The technique involves the use of a solid catalyst with oxygen gas as the oxidant.This necessitated relatively high mixing intensities;hence a three-phase Oscillatory Baffled Reactor(OBR)was used.The catalyst was based on the zeolite ZSM-5,prepared from natural kaolin by a series of delamination and activation steps and impregnated with Fe.A TiO2 nanolayer was applied,using the sol-gel method,to prevent rapid deactivation.The reactor performance was evaluated to minimize the sulfur content in the naphtha fuel.Due to the protective coating,the sulfur conversion stabilized at 90%.The results of this work establish the use of natural clay-based catalysts in a continuous,three-phase ODS,particularly with regard to proving long-term stability.It also showed that modest ODS can be achieved using an environmentally friendly oxidant,at mild operating conditions,whilst maintaining stability.

关键词： Natural kaoline Desulfurization Three-phase Oscillatory baffled reactor

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RPL-Based IoT Networks under Decreased Rank Attack:Performance Analysis in Static and Mobile Environments

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Computers, Materials & Continua 2024年第1期78卷 227-247页

作者： Amal Hkiri Mouna Karmani Omar Ben Bahri Ahmed Mohammed Murayr Fawaz hassan Alasmari mohsen Machhout Physic Department Electronics and Micro-Electronics LaboratoryFaculty of Sciences of MonastirMonastir5000Tunisia Department of Science and Technology College of RanyahTaif UniversityP.O.Box 11099Taif21944Saudi Arabia

The RPL(IPv6 Routing Protocol for Low-Power and Lossy Networks)protocol is essential for efficient communi-cation within the Internet of Things(IoT)ecosystem.Despite its significance,RPL’s susceptibility to attacks remains a concern.This paper presents a comprehensive simulation-based analysis of the RPL protocol’s vulnerability to the decreased rank attack in both static andmobilenetwork environments.We employ the Random Direction Mobility Model(RDM)for mobile scenarios within the Cooja simulator.Our systematic evaluation focuses on critical performance metrics,including Packet Delivery Ratio(PDR),Average End to End Delay(AE2ED),throughput,Expected Transmission Count(ETX),and Average Power Consumption(APC).Our findings illuminate the disruptive impact of this attack on the routing hierarchy,resulting in decreased PDR and throughput,increased AE2ED,ETX,and APC.These results underscore the urgent need for robust security measures to protect RPL-based IoT networks.Furthermore,our study emphasizes the exacerbated impact of the attack in mobile scenarios,highlighting the evolving security requirements of IoT networks.

关键词： RPL decreased rank attacks mobility random direction model

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Correlation between structural phase transition and physical properties of Co2+/Gd3+ co-substituted copper ferrite

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Journal of Rare Earths 2024年第7期42卷 1344-1353页

作者： mohsen Choupani Ahmad Gholizadeh School of Physics Damghan University

The doping of the spinel ferrites with selective cations usually improves the properties of the parent ferrite.The effect of Co2+/Gd3+co-substitution on the microstructure,optical,and magnetic properties of Cu1-xCoxFe2-xGdxO4prepared by the citrate-nitrate auto-combustion synthesis was investigated.Characterization of the samples was performed with powder X-ray diffraction（XRD）,Raman and Fouriertransform infrared（FTIR） spectroscopy,field-emission scanning electron microscopy,X-ray energydispersive spectroscopy,UV-Vis spectroscopy,and a vibrating sample magnetometer.The results of XRD,Raman,and FTIR analysis show a gradual structural phase transition from a tetragonal（I41/amd）structure to a cubic（Fd 3 m） structure.The bandgap energy of the studied samples is in a range of1.57-1.75 eV with a minimum in sample x=0,06 and then increases.Magnetic investigations show that the presence of Co2+/Gd3+cations in an octahedral site of the copper ferrite structure could increase saturation magnetization and coercive field from 567.9 Oe and 23.62 emu/g to 929.4 Oe and 28.27 emu/g,respectively.

关键词： Citrate-nitrate method Magnetic properties Microstructure properties Rare earths Spinel copper ferrite Structure phase transition

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The interaction of history and modern thought in the creation of Iran’s architecture by investigating the approaches of past-oriented architecture

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Frontiers of Architectural Research 2024年第3期13卷 459-486页

作者： mohsen Kamali Department of Architecture Faculty of Arts and ArchitectureYazd UniversityYazdIran

The relationship between tradition and modernity significantly influences society,culture,and architectural discourse.This philosophy offers a framework for exploring the impact of traditional architecture on contemporary Iranian architecture from different perspectives and approaches.Various viewpoints exist on whether historical architecture can be a defining characteristic of contemporary architectural discourse.Through an in-depth review of analysis-centred architectural literature,a unique method was chosen for analysing contemporary architecture and gaining insight into its creation.The main goal of this study is to establish a productive relationship between past-oriented architecture,innovative architectural concepts,and contemporary thought.This article examines three critical viewpoints,tradition as imitation,transmission,and transformation,alongside analysing their influential components on architectural form to gain insight into productively connecting with historical achievements and show that the role of history is to add new values to architecture-conscious needs that have changed during history.Ultimately,the challenge lies in finding a suitable path among diverse perspectives and reinterpretations and establishing a productive relationship with history and contemporary thought.

关键词： Tradition Modernism Past-oriented architecture Contemporary Iranian architecture Concept-oriented architecture Contemporary architectural approaches

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On the occurrence of Neoplanorbulinella Matsumaru, 1976(Foraminifera) from the late Oligocene of Central Iran(Qom Formation):Palaeobiogeographic implications

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Journal of Palaeogeography 2024年第1期13卷 80-91页

作者： Mehdi Sarfi mohsen Yazdi-Moghadam School of Earth Sciences Damghan UniversityDamghan ***Iran National Iranian Oil Company Exploration Directorate Sheikh Bahaie SquareTehran ***Iran

The shallow marine carbonates of the upper Oligocene Qom Formation yielded several occurrences of the foraminiferan genus Neoplanorbulinella Matsumaru. Neoplanorbulinella saipanensis Matsumaru has so far been recorded from the late Eocene-early Miocene of Japan and late Oligocene of NE Italy whereas N. malatyaensis Gedik is only reported from the Oligocene from its type locality in the Malatya Basin, eastern Turkey. The new records reported here from the Qom Formation indicate that both species occur in the Dobaradar section, ca. 10 km south of the city of Qom in North-Central Iran. The palaeogeographic distribution of these two species therefore has to be extended as far as the palaeolongitude of current Central Iran.The accompanying larger benthic foraminifers, including Miogypsinoides complanatus(Schlumberger),M. formosensis Yabe and Hanzawa, Spiroclypeus margaritatus(Schlumberger), Operculina complanata(Defrance), and Risananeiza pustulosa Boukhary et al., indicate the upper Chattian SBZ 23 Zone. The coexistence of the N. saipanensis and N. malatyaensis points to suitable palaeobiogeographic conditions of Central Iran to host Western and Eastern Tethyan taxa.

关键词： Larger foraminifers Planorbulinids Biostratigraphy Qom Formation Central Iran

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An Online Fake Review Detection Approach Using Famous Machine Learning Algorithms

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Computers, Materials & Continua 2024年第2期78卷 2767-2786页

作者： Asma.hassan Alshehri Department of Computer Sciences College of Computer Engineering and SciencesPrince Sattam bin Abdulaziz UniversityAl KharjSaudi Arabia

Online review platforms are becoming increasingly popular,encouraging dishonest merchants and service providers to deceive customers by creating fake reviews for their goods or services.Using Sybil accounts,bot farms,and real account purchases,immoral actors demonize rivals and advertise their goods.Most academic and industry efforts have been aimed at detecting fake/fraudulent product or service evaluations for years.The primary hurdle to identifying fraudulent reviews is the lack of a reliable means to distinguish fraudulent reviews from real ones.This paper adopts a semi-supervised machine learning method to detect fake reviews on any website,among other things.Online reviews are classified using a semi-supervised approach(PU-learning)since there is a shortage of labeled data,and they are dynamic.Then,classification is performed using the machine learning techniques Support Vector Machine(SVM)and Nave Bayes.The performance of the suggested system has been compared with standard works,and experimental findings are assessed using several assessment metrics.

关键词： Security fake review semi-supervised learning ML algorithms review detection

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Engineering Nano/Microscale Chiral Self‑Assembly in 3D Printed Constructs

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Nano-Micro Letters 2024年第3期16卷 313-332页

作者： mohsen Esmaeili Ehsan Akbari Kyle George Gelareh Rezvan Nader Taheri‑Qazvini Monirosadat Sadati Department of Chemical Engineering University of South CarolinaColumbiaSC 29208USA TA Instruments Waters LLCNew CastleDE 19720USA Biomedical Engineering Program University of South CarolinaColumbiaSC 29208USA

Helical hierarchy found in biomolecules like cellulose,chitin,and collagen underpins the remarkable mechanical strength and vibrant colors observed in living organisms.This study advances the integration of helical/chiral assembly and 3D printing technology,providing precise spatial control over chiral nano/microstructures of rod-shaped colloidal nanoparticles in intricate geometries.We designed reactive chiral inks based on cellulose nanocrystal(CNC)suspensions and acrylamide monomers,enabling the chiral assembly at nano/microscale,beyond the resolution seen in printed materials.We employed a range of complementary techniques including Orthogonal Superposition rheometry and in situ rheo-optic measurements under steady shear rate conditions.These techniques help us to understand the nature of the nonlinear flow behavior of the chiral inks,and directly probe the flow-induced microstructural dynamics and phase transitions at constant shear rates,as well as their post-flow relaxation.Furthermore,we analyzed the photo-curing process to identify key parameters affecting gelation kinetics and structural integrity of the printed object within the supporting bath.These insights into the interplay between the chiral inks self-assembly dynamics,3D printing flow kinematics and photopolymerization kinetics provide a roadmap to direct the out-of-equilibrium arrangement of CNC particles in the 3D printed filaments,ranging from uniform nematic to 3D concentric chiral structures with controlled pitch length,as well as random orientation of chiral domains.Our biomimetic approach can pave the way for the creation of materials with superior mechanical properties or programable photonic responses that arise from 3D nano/microstructure and can be translated into larger scale 3D printed designs.

关键词： Directed chiral self-assembly Cellulose nanocrystals Bioinspired nanocomposite 3D printing Rheology

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