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A wealth distribution model with a non-Maxwellian collision kernel

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Chinese Physics B 2024年第7期33卷 224-231页

作者：孟俊周霞赖绍永 college of Mathematics and Statistics Kashi UniversityKashi 844006China college of Mathematics and Physics Mianyang Teacher's CollegeMianyang 621000China School of Mathematics Southwestern University of Finance and EconomicsChengdu 611130China

A non-Maxwellian collision kernel is employed to study the evolution of wealth distribution in a multi-agent *** collision kernel divides agents into two different groups under certain conditions. Applying the kinetic theory of rarefied gases, we construct a two-group kinetic model for the evolution of wealth distribution. Under the continuous trading limit, the Fokker–Planck equation is derived and its steady-state solution is obtained. For the non-Maxwellian collision kernel, we find a suitable redistribution operator to match the taxation. Our results illustrate that taxation and redistribution have the property to change the Pareto index.

关键词： kinetic theory non-Maxwellian collision kernel wealth distribution Pareto index

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The Construction of a Learning-Oriented Speaking Assessment Model in college English Based on the Online Diagnostic Assessment

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Journal of Contemporary Educational Research 2024年第2期8卷 26-33页

作者： Hua Dai Prospect college Chongqing College of Mobile CommunicationChongqing 401120China

Since language is a tool for communication,proficiency in English communication is a fundamental necessity for talent in the 21st ***,surveys reveal that most college students at private colleges possess inadequate oral English skills,and what some have learned is“mute English.”Therefore,developing their English-speaking skills is another challenge faced by students attending private *** diagnostic assessment methods are growing globally with the use of *** diagnostic assessment system is one of the online English diagnostic assessment platforms currently being widely used in ***,the present work is conducted to investigate and conduct an oral English learning-oriented assessment model in college English using the online diagnostic *** the research result,it is hoped that the study could provide useful information for improving UDig system and make a better use of it in college oral English learning and teaching.

关键词： Oral English assessment Diagnostic assessment UDig system Learning-Oriented Assessment(LOA)

Distributed adaptive resilient formation control for nonlinear multi-agent systems under DoS attacks

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Science China(Information Sciences) 2024年第10期67卷 391-392页

作者： Hao WEN Yongming LI Shaocheng TONG college of Science Liaoning University of Technology

The cooperative control for multi-agent systems(MASs)with fixed topology [1–3] has been extensively studied recently. However, in practice, denial-of-service(DoS) attacks become an increasingly important issue due to... 详细信息

关键词： Directed graphs

Progress in the generation of spinal cord organoids over the past decade and future perspectives

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Neural Regeneration Research 2024年第5期19卷 1013-1019页

作者： Gang Zhou Siyuan Pang Yongning Li Jun Gao Department of Neurosurgery Peking Union Medical College HospitalChinese Academy of Medical Sciences&Peking Union Medical CollegeBeijingChina Department of International Medical Service Peking Union Medical College HospitalChinese Academy of Medical Sciences&Peking Union Medical CollegeBeijingChina

Spinal cord organoids are three-dimensional tissues derived from stem cells that recapitulate the primary morphological and functional characteristics of the spinal cord in *** emerging bioengineering methods have led to the optimization of cell culture protocols,spinal cord organoids technology has made remarkable advancements in the past *** literature search found that current spinal cord organoids do not only dynamically simulate neural tube formation but also exhibit diverse cytoarchitecture along the dorsal-ventral and rostral-caudal ***,fused organoids that integrate motor neurons and other regionally specific organoids exhibit intricate neural circuits that allows for functional *** qualities make spinal cord organoids valuable tools for disease modeling,drug screening,and tissue *** utilizing this emergent technology,researchers have made significant progress in investigating the pathogenesis and potential therapeutic targets of spinal cord ***,at present,spinal cord organoid technology remains in its infancy and has not been widely applied in translational *** of the next generation of spinal cord organoids will depend on good manufacturing practice standards and needs to focus on diverse cell phenotypes and electrophysiological functionality evaluation.

关键词： development organoid-on-a-chip pluripotent stem cells progress spinal cord diseases spinal cord organoids vascularization

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Study on Static Deflection Model of MEMS Capacitive Microwave Power Sensors

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Chinese Journal of Electronics 2024年第5期33卷 1188-1195页

作者： Ye JIN Debo WANG college of Electronic and Optical Engineering & college of Flexible Electronics (Future Technology) Nanjing University of Posts and Telecommunications college of Integrated Circuit Science and Engineering Nanjing University of Posts and Telecommunications

In this paper, a static deflection model of MEMS cantilever beam is proposed, which can better study the force deformation of micro-electro-mechanical system(MEMS) cantilever beam and the output characteristics of capacitive microwave power sensor. The deflection curve is used to describe the deformation of the cantilever beam and then the overload power and sensitivity of this power sensor are derived. It is found that the overload power decreases with the beam length, and increases with the initial height of beam. The sensitivity increases with the beam length, and has a linear growth relationship with the measuring electrode width. A MEMS dual-channel microwave power sensor is designed, fabricated and measured. At a microwave signal frequency of 10 GHz, the sensitivity of the sensor is measured to be 0.11 V/W for the thermoelectric detection channel and 65.17 fF/W for the capacitive detection channel. The sensitivity calculated by the lumped model is 92.93 fF/W, that by the pivot model is 50.88 fF/W,and that by the deflection model proposed in this work is 75.21 fF/W. Therefore, the theoretical result of the static deflection model is more consistent with the measured result and has better accuracy than the traditional lumped model and pivot model.

关键词： Microwave measurement Micromechanical devices Microelectromechanical systems Sensitivity Voltage measurement Accuracy Deformation Micro-electro-mechanical system (MEMS) cantilever beam Static deflection model Power sensor Overload power

Image Fusion Based on Bioinspired Rattlesnake Visual Mechanism Under Lighting Environments of Day and Night Two Levels

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Journal of Bionic Engineering 2024年第3期21卷 1496-1510页

作者： Yong Wang Hongmin Zou college of Communication Engineering Jilin UniversityChangchun130012China

This study,grounded in Waxman fusion method,introduces an algorithm for the fusion of visible and infrared images,tailored to a two-level lighting environment,inspired by the mathematical model of the visual receptive field of rattlesnakes and the two-mode cells'*** research presented here is segmented into three *** the first segment,we design a preprocessing module to judge the ambient light intensity and divide the lighting environment into two levels:day and *** second segment proposes two distinct network structures designed specifically for these daytime and nighttime *** the daytime images,where visible light information is predominant,we feed the ON-VIS signal and the IR-enhanced visual signal into the central excitation and surrounding suppression regions of the ON-center receptive field in the B channel,***,for nighttime images where infrared information takes precedence,the ON-IR signal and the Visual-enhanced IR signal are separately input into the central excitation and surrounding suppression regions of the ON-center receptive field in the B *** outcome is a pseudo-color fused *** third segment employs five different no-reference image quality assessment methods to evaluate the quality of thirteen sets of pseudo-color images produced by fusing infrared and visible *** images are then compared with those obtained by six other methods cited in the relevant *** empirical results indicate that this study's outcomes surpass the comparative results in terms of average gradient and spatial *** one or two sets of fused images underperformed in terms of standard deviation and entropy when compared to the control *** sets of fused images did not perform as well as the comparison in the QAB/F *** conclusion,the fused images generated through the proposed method show superior performance in terms of scene detail,visual perception,and image sharpness

关键词： Rattlesnake Visible image Infrared image Daylight Bionic

Multidimensional coupled structure-activity relationship models for replacement of SF_(6)

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High Voltage 2024年第2期9卷 484-494页

作者： Mi Zhang Hua Hou Baoshan Wang college of Chemistry and Molecular Sciences Wuhan UniversityWuhanChina

Computational screening of single gases to replace SF_(6)for electrical insulation has been challenged by the difficulty in combining various mutually exclusive properties especially for dielectric performance with liquefaction and environmental *** reveal the inherent correlations between dielectric strength(Er),boiling point(Tb),and global warming potential(GWP)of dielectric materials,a coupled structure-activity relationship(CSAR)model has been proposed for the first *** means of the generic descriptors,as deduced from the electrostatic potentials,and the specific descriptors,as introduced from the respective microscopic mechanisms,the complex interdependence between Er,Tb,and GWP of the insulation gases is quantitatively characterised by the 3-D coupling *** coupling mechanism for the right balance of properties is uncovered in terms of the first-principle *** CSAR model outperforms the previous SAR models in predicting Er,Tb,and GWP simultaneously in a self-consistent *** importantly,the concept of CSAR could be extended readily to any multidimensional macroscopic *** replacement compounds have been identified tentatively to be the promising candidates to replace SF_(6)using the CSAR model.

关键词： properties. dielectric insulation

Study on force chain evolution of rice straw with different length during vibrational compression

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Particuology 2024年第2期85卷 310-322页

作者： Han Tang Wenlong Xu Guixuan Zhu Changsu Xu Jinwu Wang college of Engineering Northeast Agricultural UniversityHarbin150030China

This paper explores the mechanism of force chain evolution and voidage change under vibrational and non-vibrational compression conditions of rice straw of different *** were used to explore the force chain evolution and voidage variation mechanism under different *** re-sults show that under non-vibrational compression,the strong force chain passes from top to bottom in vertical direction and from center to periphery in tangential *** vibrational compression,the force chain passes from top and bottom to center in vertical direction and the force chain evolves from outer ring to interior and exterior in tangential *** number of strong chains,voidage and standard deviation of the mean pressure under vibratory compression are lower than the values under non-vibratory *** promotes stress transfer and enhancement,velocity enhancement and density *** study analyzes the mechanical properties of different lengths straw during vibrational and non-vibrational compression from a detailed viewpoint.

关键词： Straw compression Voidage Discrete element method Mechanical properties Force chain transmission

Influence of liquid film shape on evaporation performance of agitated thin film evaporator

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Chinese Physics B 2024年第8期33卷 305-314页

作者：顾鑫强黄瑶邹鲲彭倚天 college of Mechanical Engineering Donghua UniversityShanghai 201620China

The agitated thin film evaporator(ATFE),which is known for its high efficiency,force the material to form a film through the scraping process of a scraper,followed by evaporation and *** complex shape of the liquid film inside the evaporator can significantly affect its evaporation *** work explores how change in shape of the liquid films affect the evaporation of the materials with non-Newtonian characteristics,achieved by changing the structure of the *** the distribution of circumferential temperature,viscosity,and mass transfer of the flat liquid film shows that the film evaporates rapidly in shear-thinning *** wavy liquid films are developed by using shear-thinning theory,emphasizing the flow condition in the thinning area and the factors contributing to the exceptional evaporation *** exploration is conducted on the spread patterns of the wavy liquid film and flat liquid film on the evaporation wall throughout the *** is noted that breaking the wavy liquid film on the evaporating wall during evaporation is challenging due to its film-forming *** which the fundamental causes are demonstrated by acquiring the data regarding the flow rate and temperature of the liquid *** definitive findings of the analysis reveal a significant improvement in the evaporation capability of the wavy liquid *** enhancement is attributed to increasing the shear-thinning areas and maintaining the overall shape of the film throughout the entire evaporation process.

关键词： liquid film shape shear-thinning fluids flow characteristics evaporative heat transfer

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