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Medical image segmentation using improved FCM

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science china(Information sciences) 2012年第5期55卷 1052-1061页

作者： ZHANG XiaoFeng 1,2,ZHANG CaiMing 1,3,4,TANG WenJing 1,2 & WEI ZhenWen 1 1 school of Computer science and Technology,Shandong university,jinan 250101,china 2 school of Information and Electrical Engineering,Ludong university,Yantai 264025,china 3 school of Computer science and Technology,Shandong university of Finance and Economics,jinan 250014,china 4 Shandong Province Key Lab of Digital Media Technology,jinan 250014,china 1. school of Computer science and Technology Shandong University Jinan 250101 China2. School of Information and Electrical Engineering Ludong University Yantai 264025 China3. School of Computer Science and Technology Shandong University of Finance and Economics Jinan 250014 China4. Shandong Province Key Lab of Digital Media Technology Jinan 250014 China

Image segmentation is one of the most important problems in medical image processing,and the existence of partial volume effect and other phenomena makes the problem much more *** C-means,as an effective tool to deal with PVE,however,is faced with great challenges in *** at this,this paper proposes one improved FCM algorithm based on the histogram of the given image,which will be denoted as HisFCM and divided into two *** first phase will retrieve several intervals on which to compute cluster centroids,and the second one will perform image segmentation based on improved FCM *** with FCM and other improved algorithms,HisFCM is of much higher efficiency with satisfying *** on medical images show that HisFCM can achieve good segmentation results in less than 0.1 second,and can satisfy real-time requirements of medical image processing.

关键词： FCM histogram image segmentation medical image processing

Microstructure and diffraction pattern changes resulted from long-term aging of martensite CuZnAlMnNi shape memory alloy

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Rare Metals 2002年第4期21卷 308-312页

作者： BAIYujun WANGShouren 等 MechanicalDepartment ShandongUniversityofScienceandTechnologyJinan250031China InstituteofMechanicalEngineering JinanUniversityJinan250022China

Microstructures of a CuZnAlMnNi shape memory alloy in the as-quenched andlong-term aged conditions were investigated by transmission electron microscopy. Aged for one yearin martensite phase, an equilibrium α-phase with fcc structure was observed in the M18R martensitematrix, accompanied by the appearance of a novel diffraction pattern. By analysis, it was suggestedthat the novel pattern results from the α-phase and the martensite matrix remaining in seven fineplates which produce intense secondary diffraction effect when the diffraction beams enter from onephase into another.

关键词： CuZnAlMnNi shape memory alloy martensite aging transmission electronmicroscopy

A maximum principle for partially observed optimal control of forward-backward stochastic control systems

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science china(Information sciences) 2010年第11期53卷 2205-2214页

作者： WU Zhen school of Mathematics, Shandong university, jinan 250100, china 1. school of Mathematics Shandong University Jinan 250100 China

This paper studies an optimal control problem for partially observed forward-backward stochastic control system with a convex control domain and the forward diffusion term containing control variable. A maximum principle is proved for this kind of partially observable optimal control problems and the corresponding adjoint processes are characterized by the solutions of certain forward-backward stochastic differential equations in finite-dimensional spaces. One partially observed recursive linear-quadratic (LQ) optimal control example is also given to show the application of the obtained maximum principle. An explicit observable optimal control is obtained in this example.

关键词： maximum principle partial information adjoint equation backward stochastic differential equation filtering linear-quadratic optimal control

DFT study of the conductance of molecular wire:The effect of coupling geometry and intermolecular interaction on the transport properties

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science china Chemistry 2006年第6期49卷 492-498页

作者： QI Yuanhua1,2, GUAN Daren1 & LIU Chengbu1 1. Institute of Theoretical Chemistry, Shandong university, jinan 250100, china 2. school of Physics and Microelectronics, Shandong university, jinan 250061, china 1. Institute of Theoretical Chemistry Shandong University Jinan 250100 China 2. school of Physics and Microelectronics Shandong University Jinan 250061 China

The density functional theory (DFT) combining with the non-equilibrium Green functions (NEGF) method is applied to the study of the electronic transport properties for a Di-thiol-benzene (DTB) molecule coupled to two Au(111) surfaces. The dependence of the transport properties on the bias, the coupling geometry of the molecule-electrode interface, and the intermolecular interaction are examined in detail. The results show that the existence of the hydrogen atom at the end of the DTB molecule would significantly decrease the transmission coefficients, and then the differential conductance (dI/dV). By changing the position of the DTB molecule located between two electrodes a maximum value of calculated current is observed. It is also found that the intermolecular interaction will strongly influence the transport properties of the system studied.

关键词： non-equilibrium Green functions method, transmission spectrum, the molecular projected selfconsistent Hamiltonian, projected density of state.

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基于微流控芯片的人工细胞研究进展

生物工程学报 2024年第7期40卷 2100-2119页

作者：杨雁婷邓吉楠杨军西南大学动物科学技术学院重庆400715 重庆大学生物工程学院重庆400030

合成生物学的主要目标之一是自下而上地构建人工细胞。它不仅能深入理解生命的起源和细胞功能,还能在人工细胞底盘、组织模型、工程治疗递送系统和药物筛选工具等领域发挥关键作用。然而,这一目标的实现极具挑战,细胞结构的复杂性、基... 详细信息

合成生物学的主要目标之一是自下而上地构建人工细胞。它不仅能深入理解生命的起源和细胞功能,还能在人工细胞底盘、组织模型、工程治疗递送系统和药物筛选工具等领域发挥关键作用。然而,这一目标的实现极具挑战,细胞结构的复杂性、基础模块的微型化和多样性对构建方法提出了极高要求。微流控芯片作为一种先进的分析系统,为人工细胞的构建提供了一种有效工具,能够更精确地控制其结构及局部微环境,成为当前研究的首选途径。本文综述了基于微流控芯片的人工细胞构建、操作与分析方法,强调了微环境对生命系统和人工自我维持体系的重要性,展示了人工细胞在多个关键生物医学领域的广泛应用。通过探讨不同微流控方法的优缺点及其在各种应用中的表现,帮助研究人员更深入地理解人工细胞相关研究。最后,对基于微流控技术的人工细胞研究的未来发展进行了展望,期待这一领域能够取得更大突破和进步。

关键词：合成生物学巨型脂质体微环境区室结构

Influence of Heating Rate on Double Reversible Transformation in CuZnAlMnNi Shape Memory Alloy

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Rare Metals 2001年第2期20卷 117-120页

作者： Yujun Bai, Chengwei Lu, Xiangang Xu, Guili Geng, Longwei Yin (Mechanical Department, Shandong university of science and Technology, jinan 250031, china Institute of Materials science and Engineering, Shandong university, jinan 250061, china) Shandong Univ Sci & Technol Dept Mech Jinan 250031 Peoples R China Shandong Univ Inst Mat Sci & Engn Jinan 250061 Peoples R China

The influence of heating rate on double reversible transformation in CuZnAlMnNi shape memory alloy was investigated by differential scanning calorimetry. It was found that rapid heating inhibits X -->M transformation but is favorable to the reverse martensite transformation, giving rise to the approach of the two transformation peaks. With the decrease of heating rate, the two transformation peaks separate gradually.

关键词： double reversible transformations heating rate CuZnAlMnNi shape memory alloy differential scanning calorimetry

Image denoising and deblurring: non-convex regularization, inverse diffusion and shock filter

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science china(Information sciences) 2011年第6期54卷 1184-1198页

作者： FU ShuJun 1,2,3 , ZHANG CaiMing 2 & TAI XueCheng 3,4 1 school of Mathematics, Shandong university, jinan 250100, china 2 school of Computer science and Technology, Shandong university, jinan 250101, china 3 school of Physical and Mathematical sciences, Nanyang Technological university, Singapore 639798, Singapore 4 Department of Mathematics, university of Bergen, Bergen 5008, Norway 1. school of Mathematics Shandong University Jinan 250100 China2. School of Computer Science and Technology Shandong University Jinan 250101 China3. School of Physical and Mathematical Sciences Nanyang Technological University Singapore 639798 Singapore4. Department of Mathematics University of Bergen Bergen 5008 Norway

A large number of applications in image processing and computer vision depend on image quality. In this paper, main concerns are image denoising and deblurring simultaneously in a restoration task by three types of methodologies: non-convex regularization, inverse diffusion and shock filter. We discuss their relations in the context of image deblurring: the inverse diffusion implied by the non-convex regularization, and the superior ability of deblurring edge of the shock filter to that of the inverse diffusion, both in 1D and 2D cases. Finally, we propose a region-based adaptive anisotropic diffusion with shock filter method, which shows advantages of deblurring edges, denoising and smoothing contours in experiments, compared with some related methods. Therein an idea of "divide and rule" is introduced.

关键词： image denoising image deblurring non-convex regularization inverse diffusion shock filter adaptive anisotropic diffusion

Cutting tool materials for high speed machining

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Progress in Natural science:Materials International 2005年第9期15卷 777-783页

作者： LIU Zhanqiang** and AI Xing(school of Mechanical Engineering, Shandong university, jinan 250061, china) school of Mechanical Engineering Shandong University Jinan 250061 China

High speed machining (HSM) is one of the emerging cutting processes, which is machining at a speed significantly higher than the speed commonly in use on the shop floor. In the last twenty years, high speed machining has received great attentions as a technological solution for high productivity in manufacturing. This article reviews the developments of tool materials in high speed machining operations, and the properties, applications and prospective developments of tool materials in HSM are also presented.

关键词： tool materials high speed machining.

Modeling of Mechanical Behavior of Fractal Rock Joint

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International Journal of Minerals,Metallurgy and Materials 1999年第3期13卷 157-164页

作者： jinan bang Marek A. Kwasniewski( Resources Engineering school. university of science and Technology Beijing, Bejing 100083, china)( Rock Mechanics Laboratory, Faculty of Mining and Geology, Technical university of Silesia, Gliwice , Poland) Resources Engineering school University of Science and Technology Beijing Beijing 100083 China Rock Mechanics Laboratory Faculty of Mining and Geology Technical University of Silesia Gliwice Poland

The present study shows that naturally developed fracture surfaces in rocks display the properties of self-affine fractals. Surface roughness can be quantitatively characterized by fractal dimension D and the intercept A on the log-log plot of variance: the former describes the irregularity and the later is statistically analogues to the slopes of asperities. In order to confirm the effects of these fractalparameters on the properties and mechanical behavior of rock joints, which have been observed in experiments under both normal andshear loadings, a theoretic model of rock joint is proposed on the basis of contact mechanics. The shape of asperity at contact is assumed to have a sinusoidal form in its representative scale r, with fractal dimension D and the intercept A. The model considers different local contact mechanisms, such as elastic deformation, frictional sliding and tensile fracture of the asperity. The empirical evolution law of surface damage developed in experiment is implemented into the model to up-date geometry of asperity in loading history. The effects of surface roughness characterized by D, A and re on normal and shear deformation of rock joint have been elaborated.

关键词： fractal roughness mechanical behavior rock joints fractal dimension the intercept contact mechanics normal stiffness shear stiffness, surface damage