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FUZZY RELIABILITY-BASED OPTIMUM DESIGN OF LAMINATED COMPOSITES

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Acta Mechanica Solida Sinica 2006年第3期19卷 255-263页

作者： wei junhong chen jianqiao ge rui Department of Mechanics Huazhong University of Science and Technology Wuhan 430074 China

In conventional reliability-based optimum design of structures, the reliability is computed based on the probability assumption, and the design objective and constraint are considered as deterministic ones. In many cases, however, there exist some fuzzy factors in the design objective and constraint functions. In this paper, the fuzzy reliability and fuzzy constraint are introduced to establish the fuzzy reliability-based optimum model for laminated composites. The examples show that the method developed in this paper can give consideration to both the reliability demand and the economic aspect of a structure. Since the fuzzy reliability-based optimum design is a ＇soft＇ design, the present results provide a new methodology for the effective evaluation of structural reliability and bring us an alternative optimum design idea.

关键词： fuzzy reliability fuzzy constraint the best safety level fuzzy synthetic evaluation

NOMA-Based UAV Communications for Maritime Coverage Enhancement

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China Communications 2021年第4期18卷 230-243页

作者： rui Tang wei Feng Yunfei chen Ning ge Department of Electronic Engineering Tsinghua UniversityBeijing 100084China School of Engineering University of WarwickCoventry CV47ALUK

The lack of communication infrastructure in the ocean inevitably leads to coverage blind *** addition to high-throughput marine satellites,unmanned aerial vehicles(UAVs)can be used to provide coverage for these blind zones along with onshore base *** this paper,we consider the use of UAV for maritime coverage ***,to serve more ships on the vast oceanic area with limited spectrum resources,we employ non-orthogonal multiple access(NOMA).A joint power and transmission duration allocation problem is formulated to maximize the minimum ship throughput,with the constraints on onboard communication *** from previous works,we only assume the slowly time-varying large-scale channel state information(CSI)to reduce the system cost,as the large-scale CSI is locationdependent and can be obtained according to a priori radio *** solve the non-convex problem,we decompose it into two subproblems and solve them in an iterative *** results show the effectiveness of the proposed solution.

关键词： large-scale channel state information(CSI) maritime communications non-orthogonal multiple access(NOMA) unmanned aerial vehicle(UAV)

基于PSO算法的复合材料层合板可靠性优化设计

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华中科技大学学报（自然科学版） 2006年第4期34卷 96-98页

作者：陈建桥葛锐魏俊红华中科技大学土木工程与力学学院湖北武汉430074

采用粒子群算法(PSO)分析了存在初始缺陷的复合材料层合板的可靠性优化问题.在层合板结构总厚度一定的情况下,以系统可靠度最大为目标函数,对复合材料的纤维方向角和相对厚度进行优化设计.单层板失效与否应用Tsai-Wu准则判断,采用一次... 详细信息

采用粒子群算法(PSO)分析了存在初始缺陷的复合材料层合板的可靠性优化问题.在层合板结构总厚度一定的情况下,以系统可靠度最大为目标函数,对复合材料的纤维方向角和相对厚度进行优化设计.单层板失效与否应用Tsai-Wu准则判断,采用一次二阶矩法(FORM)计算和评价失效概率.通过具体算例及借鉴遗传算法中的在线性能和离线性能评估准则,对粒子群算法的收敛性能进行评估,结果表明:与遗传算法相比,该方法具有操作简单、计算效率高等特点,对复合材料层合结构的可靠性优化设计十分有效.

关键词：复合材料层合板可靠性优化设计粒子群优化

Progress in electrode materials for the industrialization of sodium-ion batteries

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Progress in Natural Science:Materials International 2023年第1期33卷 1-7页

作者： Zhaoxin Guo Guangdong Qian Chunying Wang ge Zhang Ruofan Yin wei-Di Liu rui Liu Yanan chen School of Materials Science and Engineering Shandong University of Science and Technology School of Materials Science and Engineering Tianjin University Australian Institute for Bioengineering and Nanotechnology The University of Queensland

In recent years, sodium-ion batteries(SIBs) have received renewed attention due to the continued rise in lithium prices. SIBs are promising to replace lithium-ion batteries under various application scenarios, such as large-scale energy storage systems and low-speed electric vehicles. As the core of SIBs, electrode materials are the key factor demining the electrochemical performance. Key drawback, including cycle stability, air stability and energy density, are refraining the development of SIBs off-industrialization. For a systematic understanding on the development of SIBs, in this review, we summarized the progress of SIBs from the industrialization viewpoint,including the fabrication methods suitable for large scale production of electrode materials of SIBs, and the optimization strategies to improve electrochemical performance. Finally, we proposed promising directions for future development of electrode materials for SIBs toward industrialization.

关键词： Sodium-ion batteries Electrode materials Industrialization

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复合材料层合板的模糊稳健设计

应用力学学报 2008年第2期25卷 244-246页

作者：魏俊红陈建桥葛锐曹莹华中科技大学武汉430074

提出对复合材料结构进行稳健可靠性设计,设计中同时考虑了随机因素和模糊因素的影响。首先考虑约束的模糊性,建立了复合材料层合板的模糊优化设计模型。在模糊优化设计的基础上,考虑纤维角度和单层板厚度的变异对模糊约束的影响,进一步... 详细信息

提出对复合材料结构进行稳健可靠性设计,设计中同时考虑了随机因素和模糊因素的影响。首先考虑约束的模糊性,建立了复合材料层合板的模糊优化设计模型。在模糊优化设计的基础上,考虑纤维角度和单层板厚度的变异对模糊约束的影响,进一步研究了复合材料层合板的模糊稳健设计。算例说明了本文提出的方法的有效性,对复合材料结构的合理设计具有一定的指导意义。

关键词：复合材料模糊约束模糊稳健设计

Improved Particle Swarm Optimization for Structural Engineering Design

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Improved Particle Swarm Optimization for Structural Engineer...

Salvage of venoarterial extracorporeal membrane oxygenation following prolonged cardiopulmonary resuscitation and failure of catheter-directed thrombectomy for massive pulmonary embolism in a young patient

第一届工程科学与力学中的计算方法国际会议

作者： rui ge jianqiao chen and junhong wei Department of Mechanics Huazhong University of Science & Technology 430074 Wuhan China

＜正＞To overcome the difficulties occurring in the particle swarm optimization （PSO） such as the problem of premature convergence and / or slow search speed, this paper proposes an improved PSO （IPSO） algorithm to guarantee the convergence and get the global optimization solution for complex problems. Particles in PSO are anticipated to fly to their best position in the process of searching, but some particles will depart from the ideal routine owing to the uncertainty factors. In this paper a special mutation operator is introduced to make particles explore the search space more efficiently. The novel strategy produces a variation of the speed, which makes the algorithm explore the local and global minima thoroughly at the same time and improve the capability of the algorithm. The computational study of examples shows that the proposed method can not only significantly speed up the convergence, but also effectively solve the premature convergence problem.

关键词： particle swarm optimization structural engineering design intelligent optimization algorithm evolutionary algorithm

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World Journal of Emergency Medicine 2023年第2期14卷 161-164页

作者： ge Yu Dong-po wei Hui Xie Jian Lu Jun-li Zhao Shuang Li wei chen rui-lan Wang Department of Emergency and Critical Care Medicine Shanghai General Hospital(Shanghai First People’s Hospital)Shanghai Jiao Tong University School of MedicineShanghai 200080China Department of Cardiology Shanghai Municipal Hospital of Traditional Chinese MedicineShanghai University of Traditional Chinese MedicineShanghai 200071China Department of Cardiology Shanghai Fourth People’s Hospital Affiliated to Tongji UniversityShanghai 200434China

Dear editor,Acute massive pulmonary embolism(PE) is a common life-threatening disease with high mortality of up to 30%–50%.[1,2]Potential heterogeneous reasons for PE remain controversial, and its treatment strategie... 详细信息

关键词： Acute mortality massive

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Asian Journal of Andrology 2023年第1期25卷 132-136页

作者： wei-Hao Shao Cai-Fang Zheng Yong-Chao ge Xiao-rui chen Bo-Wen Zhang Gai-Li Wang wei-Dong Zhang Department of Epidemiology School of Public HealthZhengzhou UniversityZhengzhou 450001China Department of Urology The Third People's Hospital of ZhengzhouZhengzhou 450000China

A cross-sectional study was conducted to estimate the age-stratified normal levels and age-related changes in the risk predictors of benign prostatic hyperplasia(BPH)progression.A total of 4706 male participants aged 40 years or older in Zhengzhou(China)were *** values of the International Prostate Symptom Score(IPSS),prostate-specific antigen(PSA),prostate volume(PV),and postvoid residual urine volume(PVR)significantly increased with *** relationships between age and IPSS scores≥8(P for nonlinearity=0.046),PSA level≥1.6 ng ml^(-1),PV≥31 ml,or PVR≥39 ml(all P for nonlinearityge of 61 years,the risk indicators related to BPH progression were positively correlated with age(odds ratio[OR]>1),regardless of the predictors of the IPSS score,PSA level,PV,or PVR;and the OR values increased ***,after the age of 61 years,the risk predictors related to BPH progression were positively correlated with age.

关键词： aging lower urinary tract symptoms postvoid residual urine volume prostate-specific antigen prostate volume

维普期刊数据库评论

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精密及缺陷信息条件下的结构可靠性设计

力学进展 2008年第4期38卷 427-436页

作者：陈建桥魏俊红葛锐华中科技大学力学系武汉430074

概率方法一直以来被认为是处理不确定现象的最有效的方法.传统的概率可靠性模型建立在随机变量的分布函数基础上,需要较完整的数据信息.在结构设计问题中,有关载荷、抗力等影响因素的统计数据一般是稀少的或缺乏的,信息往往以非完整的... 详细信息

概率方法一直以来被认为是处理不确定现象的最有效的方法.传统的概率可靠性模型建立在随机变量的分布函数基础上,需要较完整的数据信息.在结构设计问题中,有关载荷、抗力等影响因素的统计数据一般是稀少的或缺乏的,信息往往以非完整的形式出现.此外,结构的安全设计还需考虑结构和环境的相互作用,结构设计、分析、评价以及制作过程中可能存在的误差等,有些不确定因素不能归于随机性.因此,需要发展新的结构可靠性设计模型和方法,以克服传统的概率可靠性方法的局限和不足.本文对精密及缺陷信息条件下的可靠性设计模型和方法进行综述,内容包括随机可靠性设计模型与方法、非完整信息下的可靠性分析和设计、模型误差和主观不确定的影响、复杂系统优化求解镱略、以及今后的研究展望.

关键词：可靠性设计缺陷信息模型误差主观不确定或然性理论优化策略