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Selections of data preprocessing methods and similarity metrics for gene cluster analysis

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Progress in Natural Science:Materials International 2006年第6期16卷 607-613页

作者： YANG Chunmei, WAN Baikun and GAO Xiaofeng (Department of Biomedical Engineering and Scientific Instrumentations, tianjin University, tianjin 300072, china Motorola (china) Electronics ltd., tianjin 300457, china) [a]Department of Biomedical Engineering and Scientific Instrumentations Tianjin University Tianjin China [b]Motorola (china) Electronics ltd. Tianjin China

Clustering is one of the major exploratory techniques for gene expression data analysis. Only with suitable similarity metrics and when datasets are properly preprocessed, can results of high quality be obtained in cluster analysis. In this study, gene expression datasets with external evaluation criteria were preprocessed as normalization by line, normalization by column or logarithm transformation by base-2, and were subsequently clustered by hierarchical clustering, k-means clustering and self-organizing maps (SOMs) with Pearson correlation coefficient or Euclidean distance as similarity metric. Finally, the quality of clusters was evaluated by adjusted Rand index. The results illustrate that k -means clustering and SOMs have distinct advantages over hierarchical clustering in gene clustering, and SOMs are a bit better than k-means when randomly initialized. It also shows that hierarchical clustering prefers Pearson correlation coefficient as similarity metric and dataset normalized by line. Meanwhile, k -means clustering and SOMs can produce better clusters with Euclidean distance and logarithm transformed datasets. These results will afford valuable reference to the implementation of gene expression cluster analysis.

关键词： gene expression cluster analysis data preprocessing similarity metrics Rand index.

Theory on real-time control of construction quality and progress and its application to high arc dam

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Science china(Technological Sciences) 2010年第10期53卷 2611-2618页

作者： ZHONG DengHua1, REN BingYu1, LI MingChao1, WU BinPing1 & LI MingChuan2 1 Department of Hydraulic and Hydroelectric Engineering, School of Civil Engineering, tianjin University, tianjin 300072, china 2 Ertan Hydropower Development company, ltd., Chengdu 610051, china 1. Department of Hydraulic and Hydroelectric Engineering School of Civil Engineering Tianjin University Tianjin 300072 China2. Ertan Hydropower Development Company Ltd. Chengdu 610051 China

A complete scheme for solving the key scientific problems associated with high-standard,high-intensity continuous construction of high arch dams was presented. First,based on a coupling analysis of construction system decomposition and coordination for a high arc dam,a mathematical model for real-time control of construction quality and progress that considers complex constraints was developed. Second,a method of progress control was proposed based on a dynamic simulation. Third,a dynamic quality control mechanism was established based on construction information collected using a PDA. Fourth,a system for integrating collected information,progress simulation and quality control analyses under a network environment was developed. Finally,these methods were applied to a practical project to show that each aspect of a construction process can be managed effectively and that real-time monitoring and feedback control can be realized. Our methods provide new theoretical principles and technical measures for quality and progress control in the high arc dam construction process.

关键词： construction quality construction progress dynamic simulation real-time control network high arc dam

An Evaluation Method for Combustion Characteristics of Coal in Cement Industry

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Journal of Wuhan University of Technology(Materials Science) 2010年第1期25卷 174-178页

作者：陶从喜 School of Environmental Science and Engineering Tianjin University tianjin Cement Industry Design and Research Institute Co Ltd.

As the coal combustion behaviors are rather complex in the cement industry, the traditional assessment method cannot be directly applied to evaluate the quality of coal. Based on the thermal analysis tests of more than 80 kinds of anthracite and bituminous coal, three evaluation parameters, namely, burning intensity （I）, average capacity of heat release （Q）, and general burning index （S） are presented, combining with the consideration of application and calciner types in the cement industry. Taking these three parameters into consideration together is necessary. Experimental results show that the coal with higher S, lower I and higher Q can be rated as the best for the calciner in the cement industry. The quantitative indexes are given to evaluate the bituminous coal and anthracite in this paper. This new assessment method has implications for the design of calciner in the cement industry.

关键词： coal burning intensity average capacity of heat release general burning index calciner

Analysis of sea surface temperature fronts in the Taiwan Strait and its adjacent area using an advanced edge detection method

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Science china Earth Sciences 2010年第7期53卷 1008-1016页

作者： PI QingLing1,2,3 & HU JianYu1,2 1 State Key Laboratory of Marine Environmental Science, Xiamen University, Xiamen 361005, china 2 Department of Oceanography, Xiamen University, Xiamen 361005, china 3 china Communications Construction company First Harbor Consultants CO., ltd., tianjin 300222, china 1. State Key Laboratory of Marine Environmental Science Xiamen University Xiamen 361005 China2. Department of Oceanography Xiamen University Xiamen 361005 China3. China Communications Construction Company First Harbor Consultants CO. LTD. Tianjin 300222 China

A morphology-based edge detection method has been used to study sea surface temperature (SST) fronts in the Taiwan Strait and its adjacent area. The method is based on mathematical morphology with multi-dimensional and multi-structural elements. Using six years’ SST data from September 2002 to August 2008, we distinguished the large SST front like Kuroshio Front as well as the smaller ones: namely Taiwan Bank Front, Zhe-Min Coastal Front and Zhang-Yun Ridge Front. The seasonal and monthly variations of these fronts were also studied. Generally, the SST fronts are stronger in winter but weaker in summer. And the fronts are at their active stage during the period from January to May but at their declining stage during the period from July to October.

关键词： SST front remote sensing edge detection Taiwan Strait Kuroshio

Sequence stratigraphic framework and distribution of depositional systems for the Paleogene in Liaodong Bay area

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Science china Earth Sciences 2008年第S2期51卷 1-10页

作者： ZHU XiaoMin1,DONG YanLei1,YANG JunSheng1,ZHANG Qin1,LI DeJiang2,XU ChangGui3 & YU Shui3 1 National Key Laboratory of Petroleum Resources and Prospecting,china University of Petroleum,Beijing 102249,china 2 Research Institute of Petroleum Exploration and Development——Langfang,Petrochina,Langfang 065007,china 3 Technology Department of CNOOC tianjin company,tianjin 300452,china china Univ Petr Natl Key Lab Petr Resources & Prospecting Beijing 102249 Peoples R China Petrochina Res Inst Petr Explorat & Dev Langfang Langfang 065007 Peoples R China CNOOC tianjin Co Dept Technol Tianjin 300452 Peoples R China

With a comprehensive geological and geophysical data base,the Paleogene in the Liaodong Bay area,which consists of the Kongdian,Shahejie and Donghying Formations from the base to top,was divided into 4 second-order sequences and 8 third-order sequences based on the characteristics of the se-quence boundaries. Each third-order sequence is subdivided into the lowstand,lake transgressive and highstand systems tracts. The Lowstand systems tract (LST) is mainly composed of progradational parasequence sets,while the lake transgressive systems tract (TST) largely consists of the retrograda-tional parasequence sets and the highstand systems tract (HST) is dominated by the progradational parasequence sets. The main types of depositional systems include the shallow lake,semi-deep lake,deep lake,delta,fan delta,braided fluvial delta and nearshore subaqueous fan. The braided fluvial delta and fan delta depositional systems are mainly confined to the sequences of the lower SEs4-Ek,SEs3 and SEs1+2,while the sequences of SEd3,SEd2 and SEd1 are dominated by the delta and nearshore subaqueous fan depositional systems with the latter being developed at the downthrown side of the basin-bounding fault in each sequence. The evolution of the depositional systems is always con-trolled by the paleo-tectonic setting and the ancient landform in the space and geological time. It is concluded that the most favorable reservoirs are distributed in the Liaoxi low uplift and the central Liaozhong sag.

关键词： Liaodong Bay area Paleogene sequence stratigraphy sequence boundary depositional system

Design and performance of dual-band high temperature superconducting filter

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Science china(Information Sciences) 2012年第4期55卷 956-961页

作者： JI LaiYun 1,MA Jie 1,2,SUN Jun 1,WANG Lang 1,LI YanQi 1 & LIU Bin 1 1 tianjin Hi-Tech Superconducting Electronic Co.ltd.tianjin 300384,china 2 Department of Information Engineering,Hebei University of Technology,tianjin 300130,china 1. tianjin Hi-Tech Superconducting Electronic Co. ltd Tianjin 300384 China2. Department of Information Engineering Hebei University of Technology Tianjin 300130 China

In this paper,a dual-band high temperature superconducting (HTS) filter with 14-pole and 3 cross couplings is *** equivalent model,theoretical result,coupling matrix,and the simulated result of the filter are *** desired filter is designed and fabricated using double-sided DyBa 2 Cu 3 O 7 thin films on MgO wafer 2 inches in diameter and 0.5 mm in *** filter has two passbands with frequencies 1920-1940 MHz and 1960-1980 MHz respectively,and insertion loss less than 0.2 *** measurement results show that the response of practical filters is in good agreement with that of simulated results and theoretical analysis,with the group delay variation being less than ±20 ns over 90% of the filter bandwidth for the two passbands.

关键词： HTS filter dual-band cross-coupling cascaded quadruplet structure

基于滑模PI控制的电动汽车集群出力与调频联合优化

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电力自动化设备 2024年第2期44卷 87-93页

作者：吴二博梁军黄征王要强陈天锦郑州大学电气与信息工程学院河南郑州450001 河南省电力电子与电力系统工程技术研究中心河南郑州450001 卡迪夫大学工程学院英国卡迪夫CF243AA 许继电源有限公司河南许昌461000 河南省智能充电技术重点实验室河南许昌461000

电动汽车(EV)集群在参与电网调频时,持续大量的出力可能会导致系统频率出现超调现象,且会增加系统的调频成本和对EV集群的补偿成本。在保证系统频率稳定的前提下,为了协调EV集群与发电机的出力,提出了基于滑模比例-积分(PI)控制的发电机... 详细信息

电动汽车(EV)集群在参与电网调频时,持续大量的出力可能会导致系统频率出现超调现象,且会增加系统的调频成本和对EV集群的补偿成本。在保证系统频率稳定的前提下,为了协调EV集群与发电机的出力,提出了基于滑模比例-积分(PI)控制的发电机和EV集群联合优化方法,并以系统调频成本和频率稳定为目标,对EV集群的车辆投入比例进行优化。考虑私家车、公交车、出租车这3种类型EV参与电网辅助调频,建立了EV集群参与微电网调频的单区域系统模型,通过滑模PI对EV集群进行控制,在保证频率稳定的情况下,显著减小EV集群出力;进一步对EV集群车辆投入比例参数进行优化,显著降低系统的调频成本。对发电机容量充足、不足的工况进行仿真,并对比参数优化前、后的结果,验证了所提联合优化方法的有效性和经济性。

关键词：电动汽车集群控制滑模PI控制调频联合优化

STUDY ON THE POLLUTION OF URBAN SCENIC WATER BODY BY MUNICIPAL DRAINAGE IN FLOOD SEASON AND ITS CONTROL PLANNING

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Journal of Hydrodynamics 2008年第6期20卷 797-803页

作者： TIAN Yi-mei ZHOU Ying Li Hong LIU Zhi-qiang PENG Xiu-hua School of Environmental Science and Technology Tianjin University Tianjin 300072 China Veolia Water Systems （Beijing） Co. Ltd. Beijing 100027 China Michael Baker Corporation Alexandria Virginia 22304 USA

In this article, based on river quality simulation and system optimization, a water quality model was established for scenic river after rainfall discharge in flood season, with the target of making water pollutants meet the standard in priority and saving expenditure on pollution control. With the principle of reducing sewage from combined sewage pumping station and heavily polluted initial rainwater, a mathematical multiobjective planning model was constructed for rain sewage pollution control in flood season, and one scenic river in a northern city was taken for simulation example. The results show that： the optimization result meets the requirements of planning, among which, sewage reduction from the combined pumping station accounts for 17.38% in the total reduction of rain sewage, and the reduction in the heavily polluted rain water accounts for 77.24% in the total reduction of rainwater pumping station. The planning scheme can provide theoretical basis for pollution control of scenic river in flood season, and for rational reconstruction and layout of outfalls along two banks of the river.

关键词： scenic river flood season water quality simulation water pollutant controlling multiobjective planning

Visual Dynamic Simulation and Optimization of Zhangjiuhe Diversion Project

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Transactions of tianjin University 2008年第3期14卷 186-192页

作者：钟登华刘建民熊开智付金强 School of Civil Engineering Tianjin University TEDA Investment Holding Co. ltd. Tianjin 300457 China Ertan Hydropower Development Co. ltd.

With the aim of visualizing the real-time simulation calculation of water delivery system (WDS), a structural drawing-oriented (SDO) simulation technique was presented, and applied to Zhangjiuhe Diversion Project, which is a long-distance water delivery system constructed for draw- ing water from the Zhangjiuhe River to Kunming city. Taking SIMULINK software as simulating plat-form, the technique established a visual dynamic simulation model for the system. The simulation procedure of the system was simplified,and the efficiency of modeling was also enhanced according to the modularization and reutilization of the simulation program. Furthermore, a self-optimization model was presented. Based on the digital simulation models, the on line controlled optimization link was added, and the input data can be continually optimized according to the feedback information of simulating output. The system was thus optimized automatically. Built upon MATLAB software, simulation optimization of the Zhangjiuhe Diversion Project was achieved, which provides a new way for the research of optimal operation of WDS.

关键词： Zhangjiuhe Diversion Project structural drawing-oriented technique digital simulation simulation optimization visualization