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Multiscale Isogeometric Topology Optimization with Unified Structural Skeleton

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Computer Modeling in Engineering & Sciences 2020年第3期122卷 779-803页

作者： Chen Yu qifu wang Chao Mei Zhaohui Xia National Enterprise Information Software Engineering Research Center School of Mechanical Science and EngineeringHuazhong University of Science and TechnologyWuhanChina.

This paper proposes a multiscale isogeometric topology optimization(ITO)method where the configuration and layout of microstructures are optimized *** micro scale,a shape deformation method is presented to transform a prototype microstructure(PM)for obtaining a series of graded microstructures(GMs),where microstructural skeleton based on the level set framework is applied to retain more topology features and improve the *** the macro scale calculation,the effective mechanical properties can be estimated by means of the numerical homogenization *** adopting identical non-uniform rational basis splines(NURBS)as basis functions for both parameterized level set model and isogeometric calculation model,the isogeometric analysis(IGA)is integrated into the level set method,which contributes to improving the accuracy and *** examples demonstrate that,the proposed method is effective in improving the performance and manufacturability.

关键词： Isogeometric analysis topology optimization shape deformation method structural skeleton level set method.

IGA Based Bi-Layer Fiber Angle Optimization Method for Variable Stiffness Composites

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Computer Modeling in Engineering & Sciences 2020年第7期124卷 179-202页

作者： Chao Mei qifu wang Chen Yu Zhaohui Xia School of Mechanical Science and Engineering Huazhong University of Science and TechnologyWuhan430074China

This paper presents a topology optimization method for variable stiffness composite panels with varying fiber orientation and curvilinear fiber ***-uniform rational B-Splines(NURBS)based Isogeometric analysis(IGA)is utilized for the numerical computation of the general minimum compliance *** sensitivity analysis of the structure compliance function for the density and bi-layer orientation is *** bi-layer fiber paths in the design domain are generated using streamline method and updated by divided pieces reselection method after the optimization *** common examples are tested to demonstrate the effectiveness of the *** results show that the proposed method can generate more manufacturable fiber paths than some typical topology optimization methods.

关键词： Isogeometric analysis fiber angle optimization variable stiffness

An XBi-CFAO Method for the Optimization of Multi-Layered Variable Stiffness Composites Using Isogeometric Analysis

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Computer Modeling in Engineering & Sciences 2021年第11期129卷 627-659页

作者： Chao Mei qifu wang Chen Yu Zhaohui Xia School of Mechanical Science and Engineering Huazhong University of Science&TechnologyWuhan430074China School of Mechanical Engineering Yangtze UniversityJingzhou434023China

This paper presents an effective fiber angle optimization method for two and multi-layered variable stiffness composites.A gradient-based fiber angle optimization method is developed based on isogeometric analysis(IGA).Firstly,the element densities and fiber angles for two and multi-layered composites are synchronously optimized using an extended Bi-layered continuous fiber angle optimization method(XBi-CFAO).The densities and fiber angles in the base layer are attached to the control *** structure response and sensitivity analysis are accomplished using the non-uniform rational B-spline(NURBS)based *** the benefit of the B-spline space,this method is free from checkerboards,and no additional filtering is needed to smooth the sensitivity *** the curved fiber paths are generated using the streamline method and the discontinuous fiber paths are smoothed using a partitioned selection *** proposed method in the paper can alleviate the phenomenon of fiber discontinuity,enhance information retention for the optimized fiber angles of the singular points and save calculating resources effectively.

关键词： Isogeometric analysis fiber angle optimization variable stiffness laminates fiber path optimization topology optimization

Drosophila Homolog of FMRP Maintains Genome Integrity by Interacting with Piwi

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Journal of Genetics and Genomics 2016年第1期43卷 11-24页

作者： Fangfang Jiang Falong Lu Peixue Li Wei Liu Lu Zhao qifu wang Xiaofeng Cao Lei Zhang Yong Q.Zhang State Key Laboratory for Molecular and Developmental Biology Institute of Genetics and Developmental Biology Chinese Academy of Sciences State Key Laboratory of Plant Genomics and National Center for Plant Gene Research Institute of Genetics and Developmental Biology Chinese Academy of Sciences State Key Laboratory of Molecular Biology Institute of Biochemistry and Cell Biology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Science and Technology Center Fenyang College Shanxi Medical University Department of Medical Laboratory Science Fenyang College Shanxi Medical University

Fragile X syndrome （FraX）, the most common form of inherited mental retardation, is caused by the absence of the evolutionally conserved fragile X mental retardation protein （FMRP）. While neuronal functions of FMRP have been intensively studied for the last two decades, its role in non-neuronal cells remains poorly understood. Piwi, a key component of the Piwi-interacting RNA （piRNA） pathway, plays an essential role in germline development. In the present study, we report that similar to piwi, dfmrl, the Drosophila homolog of human FMR1, is required for transposon suppression in the germlines. Genetic analyses showed that dfmrl and piwi act synergistically in heterochromatic silencing, and in inhibiting the differentiation of primordial germline cells and transposon expression. Northern analyses showed that roo piRNA expression levels are reduced in dfmrl mutant ovaries, suggesting a role of dfmrl in piRNA biogenesis. Biochemical analysis demonstrated a physical interaction between dFMRP and Piwi via their N-termini. Taken together, we propose that dFMRP cooperates with Piwi in maintaining genome integrity by regulating heterochromatic silencing in somatic cells and suppressing transposon activity via the piRNA pathway in germlines.

关键词： Fragile X syndrome FMRP piwi piRNA Germline

A NEW FEATURE-BASED MANNEQUIN MODELING METHOD

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Computer Aided Drafting,Design and Manufacturing 1997年第1期7卷 45-54页

作者： Fan Jin wang qifu Yuan Minghui Zhou Ji

This paper presents a new feature-based mannequin modeling method, which is used in 3D computer aided garment design. Different from the traditional human modeling methods, a feature-based parametric design algorithm is involved in this method and mannequin posture animation is also implemented. They can greatly satisfy the requirements of the 3D computer aided garment design. At present, this mannequin modeling method has been implemented as a part of the computer aided 3D garment design system. Several mannequins for garment design have been manufactured by using this method and the rapid prototype technique.

关键词： D computer aided garment design human modeling surface modeling parametric design posture animation rapid prototype

Method for pests detecting in stored grain based on spectral residual saliency edge detection

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Grain & Oil Science and Technology 2019年第2期2卷 33-38页

作者： Yao Qin Yanli Wu qifu wang Suping Yu College of Information Science and Engineering Henan University of TechnologyZhengzhou 450001China Key Laboratory of Grain Information Processing and Control Henan University of TechnologyMinistry of EducationZhengzhou 450001China Henan Academy of Science Applied Physics Institute Co.LtdZhengzhou 450001China Luoyang Institute of Science and Technology Department of Computer and Information EngineeringLuoyang 471000China

Pests detecting is an important research subject in grain storage *** the past decades,many edge detection methods have been applied to the edge detection of stored grain *** some of them can realize the stored grain pests detecting,precision and robustness are not good *** residual(SR)saliency edge detection defines the logarithmic spectrumof image as novelty part of the image *** remaining spectrumis converted to the airspace to obtain edge detection *** algorithm is completely based on frequency domain *** not only can effectively simplify the target detection algorithm,but also can improve the effectiveness of target *** experimental results show that the edge results of stored grain pests detected by SR method are effective and stable.

关键词： Stored grain pests Saliency detection Spectral residual (SR) Edge detection

PARAMETRIC SURFACE/SURFACE INTERSECTION

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Computer Aided Drafting,Design and Manufacturing 1994年第2期4卷 40-49页

作者： Zeng Xianglin wang qifu Zhou Ji Yu Jun

Parametric surfacelsurface intersection methods are essential in a sculptured solid modelingsystem- To improve the robustness, accuracy and topological consistence, an algorithm extendedfrom ideas in [1] and in [3] is described in this paper. Including a new rnethod for obtaining the sur-face near points; an appropriate method for estimating the marching step length; and a reliablernethod for determining singular points. Furthermore, our algorithm can evaluate intersections between offset surfaces without offset approximation. These ideas are discussed and implemented in anintegrated CADICAM system. Tested by rnany typical examples , they have been proved to be robustand efficient. Some exarnples are provided.

关键词： parametric surface intersection subdivision solid modeling

DETECTING AND DETERMINING THE CHARACTERISTIC POINTS ON THE SURFACE／SURFACE INTERSECTIONS

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Computer Aided Drafting,Design and Manufacturing 1995年第1期5卷 9-14页

作者： Zeng Xianglin wang qifu Huang Zhengdong Zhou Ji

in this paper we present a method for detecting and determining the characteristicpoints on the surfacelsurface intersection. At first , criteria for detecting the characteristic pointsare derived by aid of a theorem on algebraic curves , and then ar algorithm is presented for locaringthe characteristic points which is coupled with the numerical tracing techniques. instances are alsopresented for illustrating the capability of our algorithm.

关键词： characteristic point intersetion parametric surface

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一种动态改变惯性权重的粒子群优化算法

中国机械工程 2005年第11期16卷 945-948页

作者：王启付王战江王书亭华中科技大学武汉430074

针对粒子群优化算法的局限性,提出了一种动态改变惯性权重的粒子群算法,在优化迭代过程中,惯性权重值随粒子的位置和目标函数的性质而变化。函数测试表明,改进后的算法使收敛速度显著加快,而且不易陷入局部极值点。

关键词：粒子群优化算法动态惯性权重收敛速度