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Studies on the motion and radiation of interior plasmas in gas-filled hohlraums with different laser entrance hole sizes

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Plasma Science and Technology 2024年第7期26卷 40-47页

作者：郭亮李欣李琦李三伟胡昕李晋邓博邓克立王强强曹柱荣侯立飞车兴森杜华冰徐涛何小安李志超蒋小华蒋炜郑春阳郑无敌宋鹏丁永坤杨冬杨家敏 research Center of Laser Fusion China Academy of Engineering PhysicsMianyang 621900People’s Republic of China Institute of applied Physics and Computational Mathematics Beijing 100088People’s Republic of China

An experiment on 100 k J laser facility is performed to study the motive features and radiation properties of plasmas from different areas inside gas-filled cylindrical *** hohlraums are designed to possess one open end and one laser entrance hole(LEH)with different diameters,which would or not result in the blocking of the *** x-ray streak camera that is set at 16 degrees with respect to the hohlraum axis is applied to acquire the timeresolved x-ray images from the open *** on the images,we can study the evolutions of the wall plasma,corona bubble plasma and LEH plasma simultaneously through an equivalent view field of hohlraum ***-group flat response x-ray detectors are applied to measure the x-ray *** order to understand these characteristics,our two-dimensional radiation hydrodynamic code is used to simulate the experimental *** the accuracy of reproduction,dielectronic recombination and two parameter corrections are applied in our *** on the comparison between experiments and simulations,we quantitatively understand the blocking process of LEH and the motion effects of other *** calibrated code is beneficial to design the gas-filled hohlraum in a nearby parameter space,especially the limit size of LEH.

关键词： gas-filled hohlraum plasma expansion LEH blocking

Tamping the movement of the laser absorption cutoff position using gold foam hohlraum

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Plasma Science and Technology 2024年第5期26卷 56-61页

作者：张璐李丽灵林稚伟董云松景龙飞郑建华况龙钰黎航郑金华张继彦宋天明张志宇赵阳牛高杨冬杨家敏丁永坤 research Center of Laser Fusion China Academy of Engineering PhysicsMianyang 621900People’s Republic of China Institute of applied Physics and Computational Mathematics Beijing 100088People’s Republic of China

In indirect-driven laser fusion experiments,the movement of the laser absorption layer will distort the radiation uniformity on the *** gold foam has advantages in symmetry control and lowering wall plasma blowoff when used in an inertial confinement fusion(ICF)*** work investigates the motion of the laser absorption cutoff position using lowdensity foam gold *** is found that the motion of the laser absorption cutoff position can be significantly mitigated through optimal initial low density,tailored to a specific laser *** a short square laser pulse,the laser absorption cutoff position remains almost stationary at an initial density of approximately 0.6 g cm^(-3).For a long-shaped laser pulse,the minimal motion of the laser absorption cutoff position is observed at an initial density of about 0.1 g cm^(-3).This approach allows for the adjustment of the symmetry of the hohlraum radiation *** insights gained from this study serve as a crucial reference for optimizing the hohlraum wall density.

关键词： hohlraum symmetry laser absorption plasma blowoff gold foam

Artificial Intelligence Based Meteorological Parameter Forecasting for Optimizing Response of Nuclear Emergency Decision Support System

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原子能科学技术 2024年第10期58卷 2068-2076页

作者： BILAL Ahmed Khan HASEEB ur Rehman QAISAR Nadeem MUHAMMAD Ahmad Naveed Qureshi JAWARIA Ahad MUHAMMAD Naveed Akhtar AMJAD Farooq MASROOR Ahmad Pakistan Institute of Engineering and applied Sciences Islamabad 44000Pakistan

This paper presents a novel artificial intelligence (AI) based approach to predict crucial meteorological parameters such as temperature,pressure,and wind speed,typically calculated from computationally intensive weather research and forecasting (WRF) *** meteorological data is indispensable for simulating the release of radioactive effluents,especially in dispersion modeling for nuclear emergency decision support *** of meteorological conditions during nuclear emergencies using the conventional WRF model is very complex and ***,a new artificial neural network (ANN) based technique was proposed as a viable alternative for meteorological prediction.A multi-input multi-output neural network was trained using historical site-specific meteorological data to forecast the meteorological *** evaluation of this technique was conducted to test its performance in forecasting various parameters including atmospheric pressure,temperature,and wind speed components in both East-West and North-South *** performance of developed network was evaluated on an unknown dataset,and acquired results are within the acceptable range for all meteorological *** show that ANNs possess the capability to forecast meteorological parameters,such as temperature and pressure,at multiple spatial locations within a grid with high accuracy,utilizing input data from a single ***,accuracy is slightly compromised when predicting wind speed *** mean square error (RMSE) was utilized to report the accuracy of predicted results,with values of 1.453℃for temperature,77 Pa for predicted pressure,1.058 m/s for the wind speed of U-component and 0.959 m/s for the wind speed of *** conclusion,this approach offers a precise,efficient,and wellinformed method for administrative decision-making during nuclear emergencies.

关键词： prediction of meteorological parameters weather research and forecasting model artificial neural networks nuclear emergency support system

Improved Dwarf Mongoose Optimization Algorithm for Feature Selection:Application in Software Fault Prediction Datasets

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Journal of Bionic Engineering 2024年第4期21卷 2000-2033页

作者： Abdelaziz I.Hammouri Mohammed A.Awadallah Malik Sh.Braik Mohammed Azmi Al-Betar Majdi Beseiso Department of Computer Science Al-Balqa Applied UniversityAl-Salt19117Jordan Department of Scientific research and Graduate Studies University of Prince Mugrin42241MedinaSaudi Arabia Department of Computer Science Al-Aqsa UniversityGaza4051Palestine Artificial Intelligence research Center(AIRC) Ajman UniversityAjmanUnited Arab Emirates Department of Information Technology Al-Huson University CollegeAl-Balqa Applied UniversityAl-HusonIrbid21110Jordan

Feature selection(FS)plays a crucial role in pre-processing machine learning datasets,as it eliminates redundant features to improve classification accuracy and reduce computational *** paper presents an enhanced approach to FS for software fault prediction,specifically by enhancing the binary dwarf mongoose optimization(BDMO)algorithm with a crossover mechanism and a modified positioning updating *** proposed approach,termed iBDMOcr,aims to fortify exploration capability,promote population diversity,and lastly improve the wrapper-based FS process for software fault prediction *** gained superb performance compared to other well-esteemed optimization methods across 17 benchmark *** ranked first in 11 out of 17 datasets in terms of average classification ***,iBDMOcr outperformed other methods in terms of average fitness values and number of selected features across all *** findings demonstrate the effectiveness of iBDMOcr in addressing FS problems in software fault prediction,leading to more accurate and efficient models.

关键词： Dwarf mongoose optimization algorithm Optimization Feature selection Classification

Exploration of microscopic physical processes of Z-pinch by a modified electrostatic direct implicit particle-in-cell algorithm

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Chinese Physics B 2024年第9期33卷 433-442页

作者： Kaixuan Li Cheng Ning Ye Dong Chuang Xue Institute of applied Physics and Computational Mathematics Beijing 100088China

For investigating efficiently the stagnation kinetic-process of Z-pinch,we develop a novel modified electrostatic implicit particle-in-cell algorithm in radial one-dimension for Z-pinch simulation in which a small-angle cumulative binary collision algorithm is *** our algorithm,the electric field in z-direction is solved by a parallel electrode-plate model,the azimuthal magnetic field is obtained by Ampere’s law,and the term for charged particle gyromotion is approximated by the cross product of the averaged velocity and magnetic *** simulation results of 2 MA deuterium plasma shell Zpinch,the mass-center implosion trajectory agrees generally with that obtained by one-dimensional MHD simulation,and the plasma current also closely aligns with the external *** phase space diagrams and radial-velocity probability distributions of ions and electrons are *** main kinetic characteristic of electron motion is thermal equilibrium and oscillation,which should be oscillated around the ions,while that of ion motion is implosion *** the region of stagnation radius,the radial-velocity probability distribution of ions transits from the non-equilibrium to equilibrium state with the current increasing,while of electrons is basically the equilibrium *** the initial ion density and current peak are not high enough,the ions may not reach their thermal equilibrium state through collisions even in its stagnation phase.

关键词： Z-pinch particle-in-cell ion heating charged particle collisions

GLOBAL BOUND ON THE GRADIENT OF SOLUTIONS TO p-LAPLACE TYPE EQUATIONS WITH MIXED DATA

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Acta Mathematica Scientia 2024年第4期44卷 1394-1414页

作者： Minh-Phuong TRAN The-Quang TRAN Thanh-Nhan NGUYEN applied Analysis research Group Faculty of Mathematics and StatisticsTon Duc Thang UniversityHo Chi Minh CityVietnam Nguyen Huu Huan High School Thu Duc CityVietnam Group of Analysis and applied Mathematics Department of MathematicsHo Chi Minh City University of EducationVietnam

In this paper,the study of gradient regularity for solutions of a class of elliptic problems of p-Laplace type is *** particular,we prove a global result concerning Lorentz-Morrey regularity of the non-homogeneous boundary data problem:-div((s^(2)+|▽u|^(2)p-2/2)▽u)=-div(|f|^(p-2)f)+g inΩ,u=h in■Ω,with the(sub-elliptic)degeneracy condition s∈[0,1]and with mixed data f∈L^(p)(Q;R^(n)),g∈Lp/(p-1)(Ω;R^(n))for p∈(1,n).This problem naturally arises in various applications such as dynamics of non-Newtonian fluid theory,electro-rheology,radiation of heat,plastic moulding and many *** on the idea of level-set inequality on fractional maximal distribution functions,it enables us to carry out a global regularity result of the solution via fractional maximal *** to the significance of M_(α)and its relation with Riesz potential,estimates via fractional maximal functions allow us to bound oscillations not only for solution but also its fractional derivatives of orderα.Our approach therefore has its own interest.

关键词： gradient estimates p-Laplace quasilinear elliptic equation fractional maximal operators Lorentz-Morrey spaces

Applying the Shearlet-Based Complexity Measure for Analyzing Mass Transfer in Continuous-Flow Microchannels

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Fluid Dynamics & Materials Processing 2024年第8期20卷 1743-1758页

作者： Elena Mosheva Ivan Krasnyakov Institute of Continuous Media Mechanics UB RAS Perm614013Russia Department of applied Physics Perm National Research Polytechnic UniversityPerm614990Russia

Continuous-flow microchannels are widely employed for synthesizing various materials,including nanoparticles,polymers,and metal-organic frameworks(MOFs),to name a *** technology allows precise control over reaction parameters,resulting in purer,more uniform,and structurally stable products due to more effective mass transfer ***,continuous-flow synthesis processes may be accompanied by the emergence of spatial convective structures initiating convective *** the one hand,convection can accelerate reactions by intensifying mass *** the other hand,it may lead to non-uniformity in the final product or defects,especially in MOF microcrystal *** ability to distinguish regions of convective and diffusive mass transfer may be the key to performing higher-quality reactions and obtaining purer *** this study,we investigate,for the first time,the possibility of using the information complexity measure as a criterion for assessing the intensity of mass transfer in microchannels,considering both spatial and temporal non-uniformities of liquid’s distributions resulting from convection *** calculate the complexity using shearlet transform based on a local *** contrast to existing methods for calculating complexity,the shearlet transform based approach provides a more detailed representation of local *** analysis involves experimental images illustrating the mixing process of two non-reactive liquids in a Y-type continuous-flow microchannel under conditions of double-diffusive convection *** obtained complexity fields characterize the mixing process and structure formation,revealing variations in mass transfer intensity along the *** compare the results with cases of liquid mixing via a pure diffusive *** analysis,it was revealed that the complexity measure exhibits sensitivity to variations in the type of mass transfer,establishing its feasibility as an ind

关键词： Shearlet analysis complexity measure entropy measure convection microchannels double-diffusive instability

Quantifying the impacts of the COVID-19 pandemic lockdown and the armed conflict with Russia on Sentinel 5P TROPOMI NO_(2)changes in Ukraine

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Big Earth Data 2024年第1期8卷 58-81页

作者： Anh Phan Hiromichi Fukui Graduate School of Engineering Chubu UniversityKasugaiJapan Chubu Institute for Advanced Studies and International Digital Earth applied Science research Center(IDEAS) Chubu UniversityKasugaiJapan

This study investigated variations in nitrogen dioxide(NO_(2))levels in Ukraine during two significant periods:the COVID-19 pandemic lockdown in 2020 and the armed conflict with Russia in *** and reprocessed Sentinel 5P data products were utilized for the analysis.A machine learning model was employed to generate a business-as-usual NO_(2)time series that accounted for meteorological *** the nine most populous cities in Ukraine,during the lockdown in 2020 we observed a moderation of increases in NO_(2)levels during the lockdown compared to the pre-lockdown *** at the same months during the conflict period in 2022,we identified much more significant reductions in NO_(2)level in these cities,averaging 12.1%for original and 18.1%for reprocessed *** our examination of major urban areas,we observed reductions in NO_(2)levels in areas surrounding coal power plants damaged or destroyed by the *** the major urban areas in Ukraine,we conclude that changes in daily anthropogenic activities due to the conflict-related events had more substantial impacts on NO_(2)levels than did COVID-19 lockdown.

关键词： NO_(2) COVID-19 Russia-Ukraine armed conflict weather-normalization

Revealing the Regulation Effect of Surface Charge at Aromatic Interface to Dynamic Conformational Changes of α-Synuclein at Early Aggregation Stage

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Chinese Journal of Chemistry 2024年第16期42卷 1867-1876页

作者： Yuqi Zhang Lie Wu Xiue Jiang State Key Laboratoryof Electroanalytical Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun Jilin 130022China Schoolof applied Chemistry and Engineering University of Science and Technology of ChinaHefei Anhui 230026China research Center for Analytical Science College of ChemistryNankai UniversityTianjin 300071China

The aggregation ofα-synuclein(α-syn)is strongly influenced by membrane interfaces,but the mechanism of transition from monomers to oligomers at early aggregation stage is not ***,we investigate the adsorption and structure changes ofα-syn on oppositely charged aromatic interfaces through in-situ surface-enhanced infrared absorption(SEIRA)spectroscopy and nano-IR *** results show that the synergy of electrostatic and hydrophobic interactions leads to a“fast-slow”two-step aggregation pathway on negatively charged *** adsorption induces the formation of an extended helix structure and subsequently partial helix unwinding in NAC region,which enables the hydrophobic stacking between nearby NAC *** antiparallel β-sheet rich aggregates are gradually emerging as further interactions of monomers with the fast formed“first layer”.Monomers electrostatically adsorb on positively charged interface by C-terminus with NAC region and N-terminus stretched in solvent,which serve as an aggregation core and induce further adsorption and gradual formation of aggregates with C-terminus *** results demonstrate the modulation of surface charge and synergy of electrostatic and hydrophobic interactions on the interaction modes and aggregation pathways,which provide insights into dynamic conformation changes ofα-syn at early aggregation stage and imply the important role of spatial-temporal heterogeneity of membranes inα-synucleinopathies.

关键词： α-Synuclein Interface Early aggregation IR spectroscopy Surface analysis Analytical methods Proteins Dynamic monitoring