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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 ChinaHefei 230026China

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,*** practical applications,quadric surfaces,which are the most basic type of surfaces,are typically bounded surfaces trimmed by a sequence of *** 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 *** 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 *** error control is based on an effective solution to a set of polynomial inequality system using the root isolation *** 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

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

Homogeneous void nucleation in the presence of supersaturated vacancies and interstitials

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Journal of Materiomics 2024年第5期10卷 1147-1159页

作者： Lin shao Accelerator Laboratory Department of Nuclear EngineeringTexas A&M UniversityCollege StationTX77843USA

Homogeneous void nucleation in metals containing arbitrary vacancies and interstitials has been reexamined,with corrections made to the original work by Katz and *** void size distributions derived previously missed an exponential modification function with void size as the *** a result,void nucleation under a given vacancy supersaturation ratio is underestimated by orders of *** second improvement arises from the accuracy in calculating the vacancy arrival rate to a *** present work proposes establishing a direct relationship between the vacancy arrival rate and the available self-diffusion *** these corrections and improvements,void nucleation in pure Fe is calculated as an example,and an analytic fitting formula is *** required vacancy supersaturation ratio and interstitial-to-vacancy flux ratio for void nucleation calculations can be easily obtained from an analytical solution of rate theory calculations,in which dislocation density and displacements per atom(dpa)rate are adjustable ***,the nucleation rate calculation can be incorporated into rate theory calculations considering evolving dislocation densities,which leads to time-dependent void nucleation.

关键词： Void nucleation Voids Irradiation Swelling Defects

聚合物/表面活性剂二元载体的固体分散体提高普罗布考的溶出度

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沈阳药科大学学报 2017年第7期34卷 535-540,605页

作者：李妍妍李佳杨雁王绍宁徐晖沈阳红旗制药有限公司辽宁沈阳110179 沈阳药科大学药学院辽宁沈阳110016 沈阳药科大学制药工程学院辽宁沈阳110016

目的制备以普罗布考为模型药物的固体分散体,以聚合物与表面活性剂为二元载体材料,提高药物溶出度。方法以聚维酮PVP K3.、Kollidon VA64、Eudragit E100和Soluplus等聚合物,非离子型表面活性剂Cremophor RH40、D-α-生育酚聚乙二醇100... 详细信息

目的制备以普罗布考为模型药物的固体分散体,以聚合物与表面活性剂为二元载体材料,提高药物溶出度。方法以聚维酮PVP K3.、Kollidon VA64、Eudragit E100和Soluplus等聚合物,非离子型表面活性剂Cremophor RH40、D-α-生育酚聚乙二醇1000琥珀酸酯等为载体材料,采用溶剂挥发法制备单一载体或聚合物/表面活性剂二元载体的普罗布考固体分散体。分别在漏槽和非漏槽条件下考察固体分散体的溶出度,差示扫描量热法表征固体分散体中药物结晶状态。结果单一载体普罗布考固体分散体在非漏槽条件下的溶出度均不理想。适宜的聚合物与表面活性剂组合的二元载体固体分散体能明显增加非漏槽条件下的溶出度。热分析结果显示,药物在固体分散体中以非结晶状态存在。非漏槽条件下,VA64/RH40或聚维酮/RH40二元载体固体分散体在介质中形成纳米分散液,溶出度显著增加;而Soluplus/RH40二元载体固体分散体在介质中聚集沉淀,导致溶出度很低。结论聚合物/表面活性剂二元载体有利于提高难溶性药物的溶出,Kollidon VA64/RH40二元载体固体分散体显著提高普罗布考在非漏槽条件的溶出度。

关键词：固体分散体普罗布考溶出度聚合物/表面活性剂二元载体

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

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)

BSAlign:A Library for Nucleotide Sequence Alignment

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Genomics, Proteomics & Bioinformatics 2024年第2期22卷 135-142页

作者： Haojing shao Jue Ruan Shenzhen Branch Guangdong Laboratory of Lingnan Modern AgricultureGenome Analysis Laboratory of the Ministry of Agriculture and Rural AffairsAgricultural Genomics Institute at ShenzhenChinese Academy of Agricultural SciencesShenzhen 518120China

Increasing the accuracy of the nucleotide sequence alignment is an essential issue in genomics *** classic dynamic programming(DP)algorithms(e.g.,Smith–Waterman and Needleman–Wunsch)guarantee to produce the optimal result,their time complexity hinders the application of large-scale sequence *** optimization efforts that aim to accelerate the alignment process generally come from three perspectives:redesigning data structures[e.g.,diagonal or striped Single Instruction Multiple Data(SIMD)implementations],increasing the number of parallelisms in SIMD operations(e.g.,difference recurrence relation),or reducing search space(e.g.,banded DP).However,no methods combine all these three aspects to build an ultra-fast *** this study,we developed a Banded Striped Aligner(BSAlign)library that delivers accurate alignment results at an ultra-fast speed by knitting a series of novel methods together to take advantage of all of the aforementioned three perspectives with highlights such as active F-loop in striped vectorization and striped move in banded *** applied our new acceleration design on both regular and edit distance pairwise *** achieved 2-fold speed-up than other SIMD-based implementations for regular pairwise alignment,and 1.5-fold to 4-fold speed-up in edit distance-based implementations for long *** is implemented in C programing language and is available at https://***/ruanjue/bsalign.

关键词： Pairwise alignment Edit distance Striped vectorization Banded dynamic programming F evaluation