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冠心病合并重度颈动脉狭窄的血运重建

中国现代神经疾病杂志 2024年第1期24卷 22-26页

作者：杨寅房庆瑞王联群李军山许洋郭志刚天津大学胸科医院心血管外科、天津市心血管病研究所、天津市心血管急危重症重点实验室 300222

动脉粥样硬化是临床常见的慢性系统性血管病变,可引起冠心病和颈动脉狭窄,二者常共病且互为血运重建手术后并发症的重要危险因素,如何选择血运重建策略尚未达成共识。本文综述冠心病合并颈动脉狭窄的流行病学和血运重建策略,以为共病的... 详细信息

动脉粥样硬化是临床常见的慢性系统性血管病变,可引起冠心病和颈动脉狭窄,二者常共病且互为血运重建手术后并发症的重要危险因素,如何选择血运重建策略尚未达成共识。本文综述冠心病合并颈动脉狭窄的流行病学和血运重建策略,以为共病的有效治疗提供理论依据。

关键词：冠心病颈动脉狭窄血流动力学综述

Global Well-posedness for the Non-viscous MHD Equations with Magnetic Diffusion in Critical Besov Spaces

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Acta Mathematica Sinica,English Series 2022年第9期38卷 1493-1511页

作者： Wei Kui YE Zhao yang yin Institute of Applied Physics and Computational Mathematics P.O.Box 8009Beijing 100088P.R.China Department of Mathematics Sun Yat-sen UniversityGuangzhou 510275P.R.China

In this paper,we mainly investigate the Cauchy problem of the non-viscous MHD equations with magnetic *** first establish the local well-posedness(existence,uniqueness and continuous dependence)with initial data(u_(0),b_(0))in critical Besov spaces B_(p,1)^(d/p+1)×B_(p,1)^(d/p)with 1≤p≤∞,and give a lifespan T of the solution which depends on the norm of the Littlewood–Paley decomposition(profile)of the initial ***,we prove the global existence in critical Besov *** particular,the results of global existence also hold in Sobolev space C([0,∞);H~s(S~2))×(C([0,∞);H^(s-1)(S~2))∩L~2([0,∞);H~s(S~2)))with s>2,when the initial data satisfies∫_(S~2)b_(0)dx=0 and||u_(0)||B_(()∞,1~((S~2)))~1+||b_(0)||B_(()∞,1^(S~2))~0≤ε.It’s worth noting that our results imply some large and low regularity initial data for the global existence.

关键词： The non-viscous MHD equations with magnetic diffusion local well-posedness critical Besov spaces global existence

应用型本科物流管理专业教育与“三创”教育深度融合研究

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物流工程与管理 2024年第4期46卷 125-128页

作者：尹阳朱东红福州大学至诚学院福建福州350002 福州大学经济与管理学院福建福州350108

伴随着新时代创新创业需求的快速增长,传统意义上的高校专业教育与“三创”教育(创新、创业、创造教育)融合发展不平衡、不充分的问题逐渐暴露,无法实现协同发展与作用促进。文中以物流管理专业为对象,以“三创”教育为导向,分析专业教... 详细信息

伴随着新时代创新创业需求的快速增长,传统意义上的高校专业教育与“三创”教育(创新、创业、创造教育)融合发展不平衡、不充分的问题逐渐暴露,无法实现协同发展与作用促进。文中以物流管理专业为对象,以“三创”教育为导向,分析专业教育与“三创”教育深度融合存在的问题,并结合新时代社会需要、企业需求,探索其深度融合的路径,提出“三改两增”的改革机制,旨在培养“三创融合”型物流管理人才,服务国家和区域经济高质量发展。

关键词：应用型物流管理专业 “三创”教育

Jointly optimizing user clustering,power management,and wireless channel allocation for NOMA-based Internet of Things

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Digital Communications and Networks 2021年第1期7卷 29-36页

作者： Xiang Sun Liangkun Yu yin yang Department of Electrical&Computer Engineering University of New MexicoAlbuquerqueNM87131USA School of Computing Clemson UniversityClemsonSC29634USA

In order to accommodate the large number of Internet of Things(IoT)connections in mobile networks,Non-Orthogonal Multiple Access(NOMA)has been applied as the resource sharing mechanism in mobile access networks to improve the spectrum *** NOMA-based resource management for uplink communications comprises two problems,i.e.,user clustering and power&wireless channel *** clustering refers to assigning users in terms of IoT devices to different clusters(where users in the same cluster are sharing the wireless channels to upload their data),and power&wireless channel allocation is to optimize the transmission power of the users and the number of wireless channels allocated to the users in a *** two problems are coupled together,thus making it difficult to solve the NOMA-based resource management *** this paper,we propose a QoS-aWarE resourcE managemenT(SWEET)for NOMA algorithm to jointly optimize the user clustering,power management,and wireless channel allocation such that the number of wireless channels is minimized and the data rate requirements of the users can be *** performance of SWEET is validated via extensive simulations.

关键词： NOMA Internet of Things Resource management

Fabrication of morphology-controlled TiO_2 photocatalyst nanoparticles and improvement of photocatalytic activities by modification of Fe compounds

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Rare Metals 2015年第5期34卷 291-300页

作者： Teruhisa Ohno Szu ying Lee yin yang Department of Materials Science Graduate School of Engineering Kyushu Institute of Technology

Our previous studies suggested that redox reaction proceeded separately on specific exposed crystal faces of TiO2 nanoparticles. Site-selective deposition of metal or metal oxide on TiO2 specific exposed crystal faces successfully proceeded using the unique reactivity properties on the surface of TiO2 nanoparticles under photoexcitation. A remarkable improvement ofphotocatalytic activity of shape- controlled brookite and rutile TiO2 nanorods with modification of Fe^3＋ compounds was observed under visible light. Crystal face-selective metal compound modification on exposed crystal faces of TiO2 nanorods with brookite and futile phases was successfully prepared. Brookite and rutile TiO2 nanorods prepared by site-selective modification with metal compounds should be ideal visible-light responsive TiO2 photocatalysts because of the remarkable suppression of back electron transfer from TiO2 to oxidized metal com- pounds on the surface of the TiO2 nanorod with a brookite or rutile phase. In this paper, the development of exposed crystal face-controlled TiO2 nanorods with rutile and brookite phases was described. The obtained rutile and brookite TiO2 nanorod, showing remarkably high activity for degra- dation of organic compounds compared with the photocatalytic activities of anatase fine particles （ST-01）, is one of the most active commercially available photocatalysts for environmental cleanup in Japan. The technology of visiblelight responsive treatment for morphology-controlled rutile and brookite TiO2 nanorods by crystal face-selective modification of Fe^3＋ compounds was also discussed in this paper. The Fe^3＋ compound-modified rutile and brookite TiO2 nanorods show much higher activity than conventional visible-light responsive N-doped TiO2, which is commercially available in Japan.

关键词： Morphology-controlled TiO2 Separation of reaction sites Visible-light responsive TiO2 loaded with Fe^3+

AN EFFICIENT MOVING MESH METHOD FOR A MODEL OF TURBULENT FLOW IN CIRCULAR TUBES

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Journal of Computational Mathematics 2009年第2期27卷 388-399页

作者： yin yang Yanping Chen Yunqing Huang Hunan Key Laboratory for Computation and Simulation in Science and Engineering School of Mathematics and Computational Science Xiangtan University Xiangtan 411105 China School of Mathematical Sciences South China Normal University Guangzhou China

This paper presents an efficient moving problem with an optimal control constrained mesh method to solve a nonlinear singular condition. The physical problem is governed by a new model of turbulent flow in circular tubes proposed by Luo et al. using Prandtl＇s mixing-length theory. Our algorithm is formed by an outer iterative algorithm for handling the optimal control condition and an inner adaptive mesh redistribution algorithm for solving the singular governing equations. We discretize the nonlinear problem by using a upwinding approach, and the resulting nonlinear equations are solved by using the Newton- Raphson method. The mesh is generated and the grid points are moved by using the arc-length equidistribution principle. The numerical results demonstrate that proposed algorithm is effective in capturing the boundary layers associated with the turbulent model.

关键词： Eddy viscosity Turbulent pipe flow Boundary layer Optimal control Moving mesh

Adaptive Extended Isogeometric Analysis for Steady-State Heat Transfer in Heterogeneous Media

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Computer Modeling in Engineering & Sciences 2021年第3期126卷 1315-1332页

作者： Weihua Fang Tiantang Yu yin yang Nanjing Automation Institute of Water Conservancy and Hydrology Ministry of Water ResourcesNanjing210012China Department of Engineering Mechanics Hohai UniversityNanjing211100China Lake Research Institute Hydraulic Research Institute of Jiangsu ProvinceNanjing210017China

Steady-state heat transfer problems in heterogeneous solid are simulated by developing an adaptive extended isogeometric analysis(XIGA)method based on locally refined non-uniforms rational B-splines(LR NURBS).In the XIGA,the LR NURBS,which have a simple local refinement algorithm and good description ability for complex geometries,are employed to represent the geometry and discretize the field variables;and some special enrichment functions are introduced into the approximation of temperature field,thus the computational mesh is independent of the material interfaces,which are described with the level *** to the approximation of temperature field,a temperature gradient recovery technique for heterogeneous media is proposed,and based on the Zienkiewicz–Zhu recovery technique a posteriori error estimator is defined to automatically identify the locally refined *** convergence and performance properties of the developed method are verified by using three numerical *** numerical results show that(1)The convergence speed of the adaptive local refinement is faster than that of the uniform global refinement;(2)The convergence rate of the high-order basis functions is faster than that of the low-order basis functions;and(3)The existing inclusions change the local distributions of the temperature,and the extreme values of the temperature gradients take place around the inclusion interfaces.

关键词： Heterogeneous media steady-state heat transfer adaptive XIGA LR NURBS heat dissipation

《土官底簿》视域下明代改土归流的时间、空间与原因探析

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遵义师范学院学报 2024年第4期26卷 9-13,39页

作者：颜丙震杨胤焓贵州大学马克思主义学院贵州贵阳550025

《土官底簿》载录有众多改土归流的事例,为我们研究明代的土司政策和地方治理提供了重要史料。从这些改土归流的时间和空间分布看,明嘉靖中期以前改土归流的高潮集中于正统和成化时期的云南地区。究其原因,正统麓川之役和成化吏治败坏... 详细信息

《土官底簿》载录有众多改土归流的事例,为我们研究明代的土司政策和地方治理提供了重要史料。从这些改土归流的时间和空间分布看,明嘉靖中期以前改土归流的高潮集中于正统和成化时期的云南地区。究其原因,正统麓川之役和成化吏治败坏与之关系密切。这些改土归流的原因复杂多样,反映了明代土司承袭制度的完备性和灵活性。但更值得关注的是,《土官底簿》对改土归流的详细记载亦暴露出明王朝的土司政策与地方施政存在较大程度的背离。

关键词：《土官底簿》明代改土归流土司制度地方施政

基于改进型多目标粒子群算法的光伏并网逆变器LCLLC滤波器参数优化方法

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水电能源科学 2024年第8期42卷 213-217,196页

作者：赵永熹殷明洋范宏梅丘梅上海电力大学自动化工程学院上海200090 上海电力大学电气工程学院上海200090 浙江华云清洁能源有限公司浙江杭州310000

LCLLC型滤波器同时具有LCL和LLCL型滤波器的优点,即高频谐波衰减效果好,又可以滤除开关频率处的谐波,其性能主要取决于参数的设计。然而,LCLLC型滤波器参数设计复杂,传统设计方法过于保守且成本较高,单目标算法和传统的多目标优化算法... 详细信息

LCLLC型滤波器同时具有LCL和LLCL型滤波器的优点,即高频谐波衰减效果好,又可以滤除开关频率处的谐波,其性能主要取决于参数的设计。然而,LCLLC型滤波器参数设计复杂,传统设计方法过于保守且成本较高,单目标算法和传统的多目标优化算法存在权重选择困难、收敛性差和优化效果不佳的问题。通过对LCLLC滤波器的谐波进行分析,提出一种多目标参数优化方法,将纹波电流最小化、谐波电流衰减比最小化、总成本最小化作为优化目标,利用提出的三方竞争纵横交叉多目标粒子群算法,得到LCLLC型滤波器的最优参数组合,并利用Matlab/Simulink软件对光伏并网系统中的LCLLC型滤波器进行仿真。结果表明,设计方案正确、有效。

关键词： LCLLC滤波器参数设计多目标优化算法三方竞争机制纵横交叉方案