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Adaptive foreground and shadow segmentation using hidden conditional random fields

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第4期8卷 586-592页

作者： CHU Yi-ping ye xiu-zi QIAN Jiang ZHANG Yin ZHANG San-yuan School of Computer Science State Key Lab. of CAD ＆ CG Zhejiang University Hangzhou 310027 China

Video object segmentation is important for video surveillance, object tracking, video object recognition and video editing. An adaptive video segmentation algorithm based on hidden conditional random fields (HCRFs) is proposed, which models spatio-temporal constraints of video sequence. In order to improve the segmentation quality, the weights of spatio-temporal con- straints are adaptively updated by on-line learning for HCRFs. Shadows are the factors affecting segmentation quality. To separate foreground objects from the shadows they cast, linear transform for Gaussian distribution of the background is adopted to model the shadow. The experimental results demonstrated that the error ratio of our algorithm is reduced by 23% and 19% respectively, compared with the Gaussian mixture model (GMM) and spatio-temporal Markov random fields (MRFs).

关键词： Video segmentation Shadow elimination Hidden conditional random fields (HCRFs) On-line learning

Denoising of Chinese calligraphy tablet images based on run-length statistics and structure characteristic of character strokes

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2006年第7期7卷 1178-1186页

作者： ZHANG Jun-song YU Jin-hui MAO Guo-hong ye xiu-zi State Key Lab of CAD ＆ CG Zhejiang University Hangzhou 310027 China School of Computer Sctence China University ofGeosciences Wuhan 430074 China

In this paper, a novel approach is proposed for denoising of Chinese calligraphy tablet documents. The method includes two phases: First, a partial differential equations (PDE) based the total variation model and Otsu thresholding method are used to preprocess the calligraphy document image. Second, a new method based on run-length statistics and structure charac- teristics of Chinese characters is proposed to remove some random and ant-like noises. This includes the optimal threshold se- lection from histogram of run-length probability density, and improved Hough transform algorithm for line shape noise detection and removal. Examples are given in the paper to demonstrate the proposed method.

关键词： Denoising Tablet images Structure characteristics Character strokes

3D graphical visualization of the genetic architectures underlying complex traits in multiple environments

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第4期8卷 563-567页

作者： HU Cheng-cheng ye xiu-zi ZHANG Yin YU Rong-dong YANG Jian ZHU Jun College of Computer Science Zhejiang University Hangzhou 310027 China James D. Watson Institute of Genomic Science Zhejiang University Hangzhou 310029 China Institute of Bioinformatics. Zheiiane University. Hangzhou 310029. China

An approach for generating interactive 3D graphical visualization of the genetic architectures of complex traits in multiple environments is described. 3D graphical visualization is utilized for making improvements on traditional plots in quan- titative trait locus (QTL) mapping analysis. Interactive 3D graphical visualization for abstract expression of QTL, epistasis and their environmental interactions for experimental populations was developed in framework of user-friendly software QTLNetwork (http://***/software/qtlnetwork). Novel definition of graphical meta system and computation of virtual coordinates are used to achieve explicit but meaningful visualization. Interactive 3D graphical visualization for QTL analysis provides geneticists and breeders a powerful and easy-to-use tool to analyze and publish their research results.

关键词： Ouantitative trait locus (QTL) Visualization 3D graphical Interactive visualization

A Method of Generating Semi-Experimental Biomedical Datasets

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Journal of Beijing Institute of Technology 2024年第3期33卷 219-226页

作者： Jing Wang Naike Du zi He xiuzhu ye School of Information and Electronics Beijing Institute of TechnologyBeijing 100081China

This paper proposed a method to generate semi-experimental biomedical datasets based on full-wave simulation *** system noise such as antenna port couplings is fully considered in the proposed datasets,which is more realistic than synthetical *** this paper,datasets containing different shapes are constructed based on the relative permittivities of human ***,a back-propagation scheme is used to obtain the rough reconstructions,which will be fed into a U-net convolutional neural network(CNN)to recover the high-resolution *** results show that the network trained on the datasets generated by the proposed method can obtain satisfying reconstruction results and is promising to be applied in real-time biomedical imaging.

关键词： electromagnetic imaging dataset biomedical imaging

On the superconvergence of a WG method for the elliptic problem with variable coefficients

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Science China Mathematics 2024年第8期67卷 1899-1910页

作者： Junping Wang Xiaoshen Wang xiu ye Shangyou Zhang Peng Zhu Division of Mathematical Sciences National Science FoundationAlexandriaVA 22314USA Department of Mathematics University of Arkansas at Little RockLittle RockAR 72204USA Department of Mathematical Sciences University of DelawareNewarkDE 19716USA College of Data Science Jiaxing UniversityJiaxing 314001China

This article extends a recently developed superconvergence result for weak Galerkin(WG)approximations for modeling partial differential equations from constant coefficients to variable *** superconvergence features a rate that is two orders higher than the optimal-order error estimates in the usual energy and L^(2)*** extension from constant to variable coefficients for the modeling equations is highly *** underlying technical analysis is based on a sequence of projections and *** results confirm the superconvergence theory for second-order elliptic problems with variable coefficients.

关键词： weak Galerkin finite element methods superconvergence second-order elliptic problems stabilizerfree

Hypoglycemic effect and the mechanism of action of a polysaccharide from sweet corncob in a high-fat diet and streptozotocin-induced diabetic mice

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Food Science and Human Wellness 2024年第3期13卷 1543-1555页

作者： Xin Wang Weiye xiu ye Han Zhili Wang Yu Luo Yongqiang Ma Heilongjiang Provincial Key Laboratory of Cereals and Comprehensive Processing of Cereal Resources College of Food EngineeringHarbin University of CommerceHarbin 150028China

Type 2 diabetes mellitus(T2DM)is a metabolic disease caused by a glycolipid metabolism disorder and isletβ-cell ***-80-I is a biologically active water-soluble polysaccharide isolated from sweet corncob,an agricultural *** hypoglycemic effects of SCP-80-I on T2DM mice and its mechanisms were investigated in this ***-80-I was found to significantly reduce blood glucose and lipid deposition levels in T2DM mice,as well as decrease serum leptin and increase adiponectin ***,real time-polymerase chain reaction(RT-PCR)and Western blotting results revealed that SCP-80-I could regulate the expression of several glycolipid metabolisms and insulin secretion genes and proteins,including 5'-AMP-activated protein kinase(AMPK),carnitine palmitoyltransferase I(CPTI),and acetyl coenzyme A carboxylase(ACC)in the liver and AMPK,sirtuin1(Sirtl),peroxisome proliferator-activated receptorycoactivator-1(PGC-1α),and uncoupling protein 2(UCP2)in the *** have a hypoglycemic effect,SCP-80-1 regulated glycolipid metabolism and islet cell function in the liver by regulating the AMPK/AC C/CPT1 signaling pathway and the AMPK/Sirt1/PGC-1αand AMPK/Sirtl/UCP2 signaling *** findings improve our understanding of polysaccharides derived from sweet corncob and the use of SCP-80-I in the production of hypoglycemic foods.

关键词： Sweet corn cob polysaccharide Type 2 diabetes Signal pathway 5’-AMP-activated protein kinase(AMPK)

协同环境下CAD模型的多层次动态安全访问控制

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软件学报 2007年第9期18卷 2295-2305页

作者：方萃浩叶修梓彭维张引浙江大学计算机科学与技术学院浙江杭州310027

提出一个专门针对协同环境下CAD模型的多层次动态的安全访问控制(multi-level and dynamic security access control,简称MLDAC)模型.该模型利用一种多层次的权限模型,以简化权限定义及其分配过程,丰富了权限表达能力,实现了产品模型的... 详细信息

提出一个专门针对协同环境下CAD模型的多层次动态的安全访问控制(multi-level and dynamic security access control,简称MLDAC)模型.该模型利用一种多层次的权限模型,以简化权限定义及其分配过程,丰富了权限表达能力,实现了产品模型的多粒度访问控制.通过参照工作流的基本理念,引入权限的依赖关系及权限状态迁移概念,实现了权限的动态授权管理.通过实践证明,MLDAC模型可以对协同设计操作进行更加有效的控制,符合设计任务间的分工性、依赖性和交互性的特点.

关键词：访问控制工作流信息安全协同设计 CAD

基于离散Hopfield网络求解极大独立集的茎区选择算法以及在RNA二级结构预测中的应用

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计算机学报 2008年第1期31卷 51-58页

作者：刘琦张引叶修梓俞荣栋浙江大学沃森基因组科学研究院杭州310008 浙江大学计算机科学与技术学院杭州310027

提出了一种利用离散Hopfield网络求解图论极大独立集的启发式算法,并将其应用于RNA二级结构的茎区选择和预测当中.算法通过映射RNA序列的茎区为无向图中的节点,将预测RNA二级结构的问题转化为求解图的极大独立集的问题.定义了合理的能... 详细信息

提出了一种利用离散Hopfield网络求解图论极大独立集的启发式算法,并将其应用于RNA二级结构的茎区选择和预测当中.算法通过映射RNA序列的茎区为无向图中的节点,将预测RNA二级结构的问题转化为求解图的极大独立集的问题.定义了合理的能量变化函数,利用离散Hopfield网络进行迭代,以获得能量最优的预测结构.文中将算法与传统的最大匹配数算法以及最小自由能算法在运行时间上进行比较,并且选择特定的序列在茎区和碱基对水平上进行精度测试,结果证明该算法在效率和精度上具有一定的优势.算法的时间复杂性为max{O(n2),O(N2)},空间复杂度为O(N2),其中n为RNA序列长度,N为RNA的茎区段个数.

关键词： RNA 二级结构极大独立集离散Hopfield神经网络茎区

基于奇异值分解的RNA二级结构相似度计算方法

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浙江大学学报（工学版） 2007年第8期41卷 1249-1254页

作者：刘琦张引叶修梓俞荣栋浙江大学沃森基因组科学研究院浙江大学计算机科学与技术学院浙江杭州310027

针对传统的核糖核酸(RNA)分子结构相似度计算方法存在复杂度高、未能充分考虑二级结构全局信息的缺点,基于一种7维序列编码方法,提出了一种利用矩阵奇异值分解提取RNA二级结构数据分布特征的算法,利用提取出的奇异值向量,基于向量距离进... 详细信息

针对传统的核糖核酸(RNA)分子结构相似度计算方法存在复杂度高、未能充分考虑二级结构全局信息的缺点,基于一种7维序列编码方法,提出了一种利用矩阵奇异值分解提取RNA二级结构数据分布特征的算法,利用提取出的奇异值向量,基于向量距离进行RNA二级结构相似度比对.通过对yeast tRNA-phe、PSTV、poliovirusmutant 3种RNA分子二级结构构象的实验分析,表明了该方法的可行性和高效性.并将这种方法推广至任意两个RNA分子之间二级结构的相似度衡量,同样取得了不错的效果.

关键词： RNA二级结构相似度奇异值分解特征提取