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Particuology 2024年第8期91卷 38-49页

作者： Zeman He shaofu Du Guanying shao peiyu Li Lei Sheng Gaohong He Xiaobin Jiang Wu Xiao State Key Laboratory of Fine Chemicals School of Chemical EngineeringEngineering Laboratory for Petrochemical Energy-efficient Separation Technology of Liaoning ProvinceDalian University of TechnologyDalian 116024China

Cooling crystallization is an important separation process and particuology technology that requires accurate nucleation control ***,we introduced the polymeric hollow fiber membrane with proper thermal properties as the effective nucleation induction interface during cooling *** heterogeneous nucleation control mechanism was introduced based on classical nucleation theory and the thermal transfer *** properties and the thermal conductivity of two kinds of polymeric membranes,polytetrafluoroethylene(PTFE)and polyethersulfone(PES),were measured and simulated with the developed *** two membranes possessed different nucleation induction periods,nucleation rates and crystallization performances,which validated that the hollow fiber membrane module could effectively accelerate the nucleation process compared to conventional cooling crystallization owing to the shorter nucleation induction period and the reduced solution surface *** to the higher hydrophobicity and the lower roughness of the membrane surface,the PTFE membrane possessed a more moderate performance in generating stable heterogeneous nucleation than the one of PES ***,the adjustable membrane property enabled the hollow fiber membrane-assisted cooling crystallization to possess the accurate nucleation control and desired terminal particle products.

关键词： Cooling crystallization Nucleation Particle process Hollow fiber membrane Induction period Process control

Can Digital Village Construction Help Upgrade Rural Household Consumption?An Empirical Examination Based on China’s Rural Household Survey Data

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Contemporary Social Sciences 2023年第4期8卷 1-24页

作者： shao peiyu Liu Hui Wang Yang Liu Changjun School of Statistics Chengdu University of Information Technology Institute of Marxism Beijing Academy of Social Sciences

Digital village construction opens a new vista for fulfilling consumption capabilities and optimizing consumption patterns in rural *** this research,we used the microdata on rural households from the 2019 China Household Finance Survey(CHFS)to conduct an empirical examination of the impact of digital village construction on the upgrading of rural household consumption and its possible influence mechanisms in the endogenous switching regression(ESR)*** research findings can be summarized in three ***,digital village construction has significantly contributed positive contributions to the improvements and upgrading of rural household ***,digital village construction can help upgrade rural household consumption by increasing their participation in online shopping and expanding online shopping ***,digital village construction means different things to rural households at different levels of risk exposure,with its facilitation to consumption upgrades in proportion to income risks facing rural *** research findings,which came from an extensive,in-depth exploration of the factors influencing rural household consumption,are of practical significance and policy value to the stimulating and fulfilling of consumption potentials among rural households.

关键词： digital village consumption upgrades influence mechanisms endogenous switching regression(ESR)

Pseudoeffective thresholds and cohomology of twisted symmetric tensor fields on irreducible Hermitian symmetric spaces

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Science China Mathematics 2024年第11期67卷 2433-2452页

作者： Feng shao Institute of Mathematics Academy of Mathematics and Systems ScienceChinese Academy of Sciences School of Mathematical Sciences University of Chinese Academy of Sciences

Let X be an irreducible Hermitian symmetric space of compact type(IHSS for short).In this paper,we give the irreducible decomposition of *** a by-product,we give a cohomological characterization of the rank of ***,we introduce pseudoeffective thresholds to measure the bigness of tangent bundles of smooth complex projective varieties precisely and calculate them for irreducible Hermitian symmetric spaces of compact type.

关键词： tangent bundle pseudoeffective threshold irreducible Hermitian symmetric space of compact type (IHSS) multiplicity free action

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Interview with optical scientist and engineer Joseph Braat

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Advanced Photonics 2024年第3期6卷 7-12页

作者： Yifeng shao Delft University of Technology

Joseph Braat(professor emeritus TU Delft and former research fellow at Philips Research) received the 2019 Holst Memorial Lecture Award for his important contributions in to diffractionlimited optical imaging and scan...

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基于2-2压电复合晶片的SH波探头研究及应用

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压电与声光 2015年第3期37卷 473-476页

作者：李旺明刘晴岩邵佩玉华东理工大学承压系统安全科学教育部重点实验室上海200237

为了获得水平偏振横波(SH波),研制开发了基于2-2压电复合晶片的SH波斜探头。通过研制的SH波探头对小口径奥氏体不锈钢管标准试块和对比试块进行测试对比试验,研究其声衰减及信噪比特性。试验结果表明,基于2-2压电复合晶片的SH波探头可... 详细信息

为了获得水平偏振横波(SH波),研制开发了基于2-2压电复合晶片的SH波斜探头。通过研制的SH波探头对小口径奥氏体不锈钢管标准试块和对比试块进行测试对比试验,研究其声衰减及信噪比特性。试验结果表明,基于2-2压电复合晶片的SH波探头可实现对小口径奥氏体不锈钢管焊缝缺陷的检测,且具有较高的检测灵敏度和信噪比。

关键词：奥氏体不锈钢管焊缝超声检测 SH波小口径 2-2压电复合晶片

Analysis of spatial distribution characteristics and driving factors of ethnicminority villages in China using geospatial technology and statistical models

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Journal of Mountain Science 2024年第8期21卷 2770-2789页

作者： shao Dandan ZOH Kyungjin Interdisciplinary Program in Landscape Architecture Graduate School of Environmental StudiesSeoul National UniversitySeoul 08826Korea Graduate School of Environmental Studies Seoul National UniversitySeoul 08826Korea

This study aims to reveal the spatial structural characteristics of 1,652 Ethnic-Minority Villages(EMV)in China and to analyze the mechanisms driving their spatial *** are a special type of settlement space that preserve a large number of historical traces of the ethnic culture of ancient *** are important carriers of China’s excellent traditional culture and are key to the implementation of rural revitalization *** this study,1652 EMV in China were selected as the research *** Nearest Neighbor Index,kernel density,and spatial autocorrelation index were employed to reveal the spatial structural characteristics of minority *** network models,spatial lag models,and geographical detectors were used to analyze the formation mechanism of spatial heterogeneity in *** results indicate that:(1)EMV exhibit significant spatial differentiation characterized by“single-core with multiple surrounding sub-centers,”“polarization between east and west,”“decreasing quantity from southwest to east coast to northeast to northwest,”and“large dispersion with small agglomeration.”(2)EMV are mainly distributed in areas rich in intangible cultural heritage,with high vegetation coverage and low altitude,far from central cities,and having limited arable land and an underdeveloped economy and transportation,particularly in shaded or riverbank areas.(3)Distance from the nearest river(X3),distance from central cities(X8),national intangible cultural heritage(X9),and NDVI(X10)were the main driving factors affecting the spatial distribution of EMV,whereas elevation(X1)and GDP(X5)had the weakest *** EMV are a relatively unique territorial spatial unit,the identification of their spatial heterogeneity characteristics not only deepens the research content of settlement geography,but also involves the assessment,protection,and development of Minority Villages,which is of great significance for the inheritance and utilization of excellent

关键词： Ethnic-Minority Villages Spatial structure Settlement geography Neural network model Spatial econometric model GeoDetector

Topologically Correct Intersection Curves of Two Trimmed Quadrics with Tolerance Control

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Journal of Systems Science & Complexity 2024年第5期37卷 2207-2239页

作者： shao Wenbing CHEN Falai Department of Mathematics University of Science and Technology of China

Surface/surface intersection is a fundamental problem in Compute Aided Design and Geometric Modeling since it is essential to solid modeling, numerically controlled machining, feature recognition, computer animation, etc. In practical applications, quadric surfaces, which are the most basic type of surfaces, are typically bounded surfaces trimmed by a sequence of planes. In this paper,a robust algorithm is proposed for computing the intersection curve segments of two trimmed quadrics based on the parametric representation of the intersection curves of two quadrics. The proposed algorithm guarantees correct topology and ensures that the approximation errors of the end points of the intersection curve segments are less than a given tolerance. The error control is based on an effective solution to a set of polynomial inequality system using the root isolation technique. Some examples are presented to validate the robustness and effectiveness of the proposed algorithm.

关键词： Polynomial inequality system root isolation surface/surface intersection tolerance control trimmed quadrics

Fear and delay effects on a food chain system with two kinds of different functional responses

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International Journal of Biomathematics 2024年第3期17卷 89-122页

作者： Yuanfu shao College of Science Guilin University of Technology GuilinGuangci 541004P.R.China

For food chain system with three populations,direct predation is the basic interaction between *** species often have different predation functional responses,so a food chain system with Holling-II response for middle predator and Beddinton-DeAngelis response for top predator is *** from direct predation,predator population can significantly impact the survival of prey population by inducing the prey's fear,but the impact often possesses a time *** paper is concentrated to explore how the fear and time delay affect the system stability and the species *** use of Lyapunov functional method and bifurcation theory,the positiveness and boundedness of solutions,local and global behavior of species,the system stability around the equilibrium states and various kinds of bifurcation are ***,some simulations are carried out to validate the main findings and the critical values of the bifurcation parameters of fear and conversion rate are *** is observed that fear and delay can not only stabilize,but also destabilize the system,which depends on the magnitude of the fear and *** system varies from unstable to stable due to the continuous increase of the prey's fear by middle *** fear induced by top predator or small delay of the prey's fear can stabilize the system,while they are sufficiently large,the system stability is to be ***,the conversion rate can also change the stability and even make the species to be *** rich dynamics like multiple stabilities and various types of bistability behaviors are also exhibited,which results in the convergence of the species from one stable equilibrium to another.

关键词： Fear functional response equilibrium bifurcation analysis bi-stability

Layered double hydroxides functionalization toward rechargeable batteries Author links open overlay panel

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Particuology 2024年第8期91卷 138-154页

作者： Jianxiong Gao Bowen Jin Mingfei shao State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical TechnologyBeijing100029China Renewable Energy Research Institute Quzhou Institute for Innovation in Resource Chemical EngineeringQuzhou324000China

Layered double hydroxides(LDHs),known as typical two-dimensional materials with unique physicochemical properties,are regarded as promising candidates in energy storage ***,some inherent defects,such as poor conductivity and limited active sites,hinder the further development of ***,various functionalization strategies(e.g.,intercalation of guest molecules;metal ions doping and defect introduction of host layer;exfoliation to monolayer;hybridization with functional materials;construction of hierarchical structure;interface engineering and phase transformation)have been used to modify the characteristics of LDHs,which provides guidance for designing novel *** this review,we discuss how these strategies improve the properties of LDH-based materials,which are expected to possess high electronic and ionic conductivity,high specific surface area and high mechanical and chemical stability ***,the application of LDH-based materials in advanced energy conversion and storage techniques,including metal-ions batteries,lithium-sulfur batteries and metal-air batteries,have been comprehensively summarized.

关键词： Layered double hydroxide Functionalization strategy Rechargeable battery

Aerial target threat assessment based on gated recurrent unit and self-attention mechanism

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Journal of Systems Engineering and Electronics 2024年第2期35卷 361-373页

作者： CHEN Chen QUAN Wei shao Zhuang School of Automation Beijing Institute of TechnologyBeijing 100081China State Key Laboratory of Intelligent Control and Decision of Complex Systems Beijing 100081China

Aerial threat assessment is a crucial link in modern air combat, whose result counts a great deal for commanders to make decisions. With the consideration that the existing threat assessment methods have difficulties in dealing with high dimensional time series target data, a threat assessment method based on self-attention mechanism and gated recurrent unit(SAGRU) is proposed. Firstly, a threat feature system including air combat situations and capability features is established. Moreover, a data augmentation process based on fractional Fourier transform(FRFT) is applied to extract more valuable information from time series situation features. Furthermore, aiming to capture key characteristics of battlefield evolution, a bidirectional GRU and SA mechanisms are designed for enhanced ***, after the concatenation of the processed air combat situation and capability features, the target threat level will be predicted by fully connected neural layers and the softmax classifier. Finally, in order to validate this model, an air combat dataset generated by a combat simulation system is introduced for model training and testing. The comparison experiments show the proposed model has structural rationality and can perform threat assessment faster and more accurately than the other existing models based on deep learning.

关键词： target threat assessment gated recurrent unit(GRU) self-attention(SA) fractional Fourier transform(FRFT)