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A New Clustering Algorithm for Categorical Attributes

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International Journal of Minerals,Metallurgy and Materials 2000年第4期14卷 318-322页

作者： Songfeng Lu, Zhengding Lu (College of computer science and {2., Huazhong university of science and {2., Wuhan 430074, china) College of computer science and {2. Huazhong University of Science and Technology Wuhan 430074 China

In traditional data clustering, similarity of a cluster of objects is measured by distance between objects. Such measures are not appropriate for categorical data. A new clustering criterion to determine the similarity between points with categorical attributes is pre- sented. Furthermore, a new clustering algorithm for categorical attributes is addressed. A single scan of the dataset yields a good clus- tering, and more additional passes can be used to improve the quality further.

关键词： data mining clustering similarity Information

A Series Piezoelectric Quartz Crystal Response Kinetics for *** Growth in the Presence of Cu(Ⅱ)

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Journal of Central south university 2000年第1期12卷 15-19页

作者： CHAI Li yuan 1,2.,WEI Wan zhi 2.YAO Shou zhuo 2.1. department of Metallurgical science and Engineering, Central {2. university of technology, Changsha 410083, china 2. College of Chemistry and Chemical Engineering, Hunan university, Changsha 1. department of Metallurgical science and Engineering Central South University of Technology 410083 Changsha China 2. College of Chemistry and Chemical Engineering Hunan University 410082 Changsha China

The kinetics on the growth of *** in the presence of Cu(Ⅱ) was studied using of series piezoelectric quartz crystal (SPQC). Arsenic ion inhibits the growth of *** , which is consistent with the previous results by other measuring methods. This further demonstrates that the SPQC can monitor the chemical activity of *** growth. Cupric ion accelerates the growth of *** . The mechanism was discussed, i. e., copper promotes the protein enzyme of *** , rusticyanin, to form over the range of cupric ion concentration studied. The reaction order of cupric ion in accelerating the bacterial growth is 0.067. The growth of *** is dependent on temperature, the apparent reaction activation energy decreases from 2..56 kJ/mol to 18.32.kJ/mol because of the addition of 10 mg/L Cu(Ⅱ) to the bacterial growth solution of pH 2.0 at initial inoculum of 10%.

关键词： series piezoelectric quartz crystal T.ferrooxidans growth kinetics sigmoid curve cupric ion

Inhibition of ethanol-induced toxicity by tanshinone ⅡA in PC12.cells

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Acta Pharmacologica Sinica 2006年第6期27卷 659-664页

作者： Xian-fang MENG~2.Xiao-jing ZOU~3 Bin PENG~2.Jing SHI~2.Xin-min GUAN~2.Chun ZHANG~(4,5)2.department of Neurobiology,Tongji Medical College,Huazhong university of {2. and technology,Wuhan 430030,china 3 department of Anesthesiology,4 department of Nephrology,Union Hospital,Tongji Medical College,Huazhong university of {2. and technology,Wuhan 43002..china department of Neurobiology Tongji Medical College Huazhong University of Science and Technology Wuhan China department of Anesthesiology Union Hospital Tongji Medical College Huazhong University of Science and Technology Wuhan China department of Nephrology Union Hospital Tongji Medical College Huazhong University of Science and Technology Wuhan China

Aim:To observe the effects of tanshinone IIA(Tan IIA)on the neurotoxicityinduced by ethanol in PC 12.cells and to explore its protective ***:PC 12.ell survival was measured by MTT *** formation of reactive oxygenspecies(ROS)and lactate dehydrogenase(LDH)release were detected by 2.,7′-dichlorofluorescin(DCF)fluorescence and calorimetric method,*** of cell apoptosis was monitored by flow *** expression ofp53 was detected by immuno-fluorescence and flow ***:Ethanolsignificantly impaired the survival of PC12.cells as demonstrated by MTT *** also induced significant ROS formation and increased LDH ***-incubation with Tan IIA in the culture medium significantly reversed these *** caused cell apoptosis and the upregulation of p53 *** anti-apoptosis effects of Tan IIA on ethanol-induced toxicity were accompanied by thedownregulation of pro-apoptotic p53 protein ***:Tan IIAcan protect neurons from apoptosis and might serve as a potential therapeuticdrug for neurological disorders induced by ethanol.

关键词： apoptosis ethanol PC12.cells p53 tanshinone ⅡA

Mining and Integrating Reliable Decision Rules for Imbalanced Cancer Gene Expression Data Sets

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Tsinghua science and technology 2012年第6期17卷 666-673页

作者： Hualong Yu 1 , Jun Ni 2., Yuanyuan Dan 3 , Sen Xu 4 1. School of computer science and Engineering, Jiangsu {2. of science and technology, Zhenjiang 2.2.03, china 2. department of Radiology, Carver College of Medicine, The {2. of Iowa, Iowa City, IA 52.42. USA 3. School of Biology and Chemical Engineering, Jiangsu {2. of science and technology, Zhenjiang 2.2.03, china 4. School of Information Engineering, Yancheng Institute of technology, Yancheng 2.4051, china School of computer science and Engineering Jiangsu University of Science and Technology Zhenjiang 212003 China|c|

There have been many skewed cancer gene expression datasets in the post-genomic era. Extraction of differential expression genes or construction of decision rules using these skewed datasets by traditional algorithms will seriously underestimate the performance of the minority class, leading to inaccurate diagnosis in clinical trails. This paper presents a skewed gene selection algorithm that introduces a weighted metric into the gene selection procedure. The extracted genes are paired as decision rules to distinguish both classes, with these decision rules then integrated into an ensemble learning framework by majority voting to recognize test examples; thus avoiding tedious data normalization and classifier construction. The mining and integrating of a few reliable decision rules gave higher or at least comparable classification performance than many traditional class imbalance learning algorithms on four benchmark imbalanced cancer gene expression datasets.

关键词： cancer gene expression data class imbalance paired differential expression genes decision ruleensemble learning majority voting

Dynamic behavior of polymer surface and the time dependence of contact angle

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science china Chemistry 2005年第6期48卷 553-559页

作者： WANG Xinping1, CHEN Zhifang1 & SHEN Zhiquan2.1. Key Laboratory of Advanced Textile Materials and Manufacturing technology of Education Ministry, department of Applied Chemistry, Zhejiang Institute of {2. and technology, Hangzhou 310033, china 2. department of Polymer {2. and Engineering, Zhejiang university, Hangzhou 31002., china 1. department of Applied Chemistry Zhejiang Institute of Science and Technology Key Laboratory of Advanced Textile Materials and Manufacturing Technology of Education Ministry 310033 Hangzhou China 2. department of Polymer science and Engineering Zhejiang University 310027 Hangzhou China

Time-dependent contact angles were measured by depositing sessile drops of wa-ter on the polymer surfaces and monitoring the drop shape as a function of time. It was found that contact angles decreased sharply with contact time and the equilibrium contact angle was finally attained after a certain time. Values of starting (θ s) and equilibrium contact angles (θ e) obtained by the sessile drop method depend on polymer properties. The Wilhelmy plate technique was used to measure advancing and receding contact angles. The variations of starting (θ s) and equilibrium contact angles (θ e), advancing (θ a) and receding contact angles (θ r) have been studied on the oxidized surface of polymers containing polybutadiene block to explore the cause of time-dependence in contact angle measurement and the meaning of θ s and θ e. The results showed the linear relationships between starting (θ s) and advancing contact angles (θ a), the equilibrium (θ e) and receding contact angles (θ r). The similar relationship was also established between the contact angle hysteresis (θ a?θ r) and differences (θ s ?θ e) in starting contact angles and equilibrium contact angles. Therefore, time-dependence in contact angle measurement was mainly attributed to the surface reconstruction when water drops were deposited on polymer surfaces. The starting contact angle was contributed by the hydrophobic component on polymer surface and the equilibrium contact angle mainly by the hydrophilic component of polymer. These results not only demonstrated the interdependency between two contact angle measurements, the sessile drop method and the Wilhelmy plate technique, but also provided the experimental evidence to explain the cause of time-dependent contact angle. This may also provide a new method to study dynamic behavior of polymer surface.

关键词： contact angle, surface dynamic behavior, polymer surface, dynamic contact angle, time-dependence.

EXISTENCE OF INFINITELY MANY SOLUTIONS FOR ELLIPTIC PROBLEMS WITH CRITICAL EXPONENT

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Acta Mathematica Scientia 2004年第3期24卷 395-402页

作者：傅红卓沈尧天 department of Mathematics South China University of Technology Guangzhou 510640 China Department of Mathematics University of Science and Technology of China Hefei 230026 China department of Mathematics South China University of Technology Guangzhou 510640 Chinahis paper is concerned with the following nonlinear Dirichlet problem:where △pu = div(| ▽u|p- 2 ▽u) is the p-Laplacian of u Ωis a bounded domain in Rn (n > 3) 1 < p < n p = -pn/n-p is the critical exponent for the Sobolev imbedding λ> 0 and f(x u) satisfies some conditions. It reaches the conclusion that this problem has infinitely many solutions. Some results as p = 2 or f(xu) = |u|q-2u where 1 < q < p are generalized.

This paper is concerned with the following nonlinear Dirichlet problem:where △pu = div(| ▽u|p- 2.▽u) is the p-Laplacian of u, Ω is a bounded domain in Rn (n > 3), 1 0 and f(x, u) satisfies some conditions. It reaches the conclusion that this problem has infinitely many solutions. Some results as p = 2.or f(x,u) = |u|q-2., where 1 < q < p, are generalized.

关键词： critical Sobolev exponent concentration compactness principle genus infinitely many solutions

A low frequency piezoelectric power harvester using a spiral-shaped bimorph

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science china(Physics,Mechanics & Astronomy) 2006年第6期49卷 649-659页

作者： HU Yuantai1,2.HU Hongping2.& YANG Jiashi3 1. Institute of Mechanics and Sensing technology,Central south {2.,Changsha 410083,china 2. department of Mechanics,Huazhong {2. of science and technology,Wuhan 430074,china 3. department of Engineering Mechanics,{2. of Nebraska,Lincoln,NE 68588-052.,USA 1. Institute of Mechanics and Sensing technology Central South University Changsha 410083 China 2. department of Mechanics Huazhong University of Science and Technology Wuhan 430074 China 3. department of Engineering Mechanics University of Nebraska Lincoln NE 68588-0526 USA

We propose a spiral-shaped piezoelectric bimorph power harvester operating with coupled flexural and extensional vibration modes for applications to low frequency energy sources. A theoretical analysis is performed and the computational results show that the spiral structure has relatively low operating frequency compared to beam power harvesters of the same size. It is found that to optimize the performance of a piezoelectric spiral-shaped harvester careful design is needed.

关键词： spiral-shaped bimorph,piezoelectric harvester,power density.

A verifiable low-level concurrent programming model based on colored Petri nets

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science china(Information sciences) 2011年第10期54卷 2013-2027页

作者： WANG ShengYuan & DONG Yuan department of computer {2. and technology,Tsinghua university,Beijing 100084,china 1. department of computer {2. and technology Tsinghua University Beijing 100084 China

Concurrent programs written in a machine-level language are being used in many areas,but the verification of such programs brings various new challenges to the programming language *** of existing contributions on verifying the safety properties of concurrent programs are for high-level languages,specifications,or calculi in the *** to the lack of abstraction at a low level,additional work is needed to extend these methods to machine-level *** paper describes an approach to integrate Petri nets into low-level concurrent programs to form a new programming model (abstract machine).A program in the programming model is a restricted version of colored Petri net,with transitions colored by assembly codes for machine-level threads,and places colored by shared data consisting of memory locations or *** analysis and verification approaches for usual Petri nets can be applied indirectly for such a low-level concurrent program.

关键词： low-level concurrent programs colored Petri nets abstract machine verification

Sound intensity radiated by Gaohu

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science china(Technological sciences) 2010年第7期53卷 1792-1797页

作者： ZHAO YueZhe1, WU ShuoXian1, QIU JianZhen1, HUANG Hong2.& WU LiLing2.1 State Key Laboratory of Subtropical Building science, south china university of technology, {2. 510640, china 2.department of Musicology, Xinghai Conservatoire of Music, {2. 510500, china 1. State Key Laboratory of Subtropical Building science South China University of Technology Guangzhou 510640 China2. Department of Musicology Xinghai Conservatoire of Music Guangzhou 510500 China

Gaohu is one of the main bowed stringed instruments used in Guangdong music and Chinese native Orchestra. However its sound intensity has never been carefully measured. In this paper the sound power measurements of Gaohu were performed in a reverberation chamber according to the Chinese national standard. Two qualified musicians performed on their own instruments. The mean sound power levels and the dynamic ranges of Gaohu were investigated by four channel acoustic measuring equipments when single notes, music scale and melodies were performed under pp, mp, f and ff dynamics. Great differences were found when Gaohu performed single notes, while the sound power levels were quite close when music scale were performed under f dynamic to those when melodies were performed under normal dynamic mark, the sound power levels of Gaohu when music scale was performed under f dynamics were suggested as the typical and representative value of the sound intensities of Gaohu instrument.

关键词： Gaohu Guangdong music sound intensities sound power level