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THREE-DIMENSIONAL NUMERICAL SIMULATION OF INTAKE MODEL WITH CROSS FLOW

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Journal of Hydrodynamics 2011年第3期23卷 314-324页

作者： HSIAO Shih-Chun Department of Hydraulics and Ocean Engineering national cheng kung university

The hydrodynamics of a pump sump consisting of a main channel, pump sump, and intake pipe is examined using Truchas a three-dimensional Navier-Stokes solver, with a Large Eddy Simulation （LES） turbulence model. The numerical results of streamwise velocity profiles and flow patterns are discussed and compared with experimental data of Ansar and Nakato. Fairly good agreement is obtained. Furthermore, unlike Ansar et al.＇s inviscid solution, the proposed numerical model includes the effect of fluid viscosity and considers more realistic simulation conditions. Simulation results show that viscosity affects the prediction of flow patterns and that the streamwise velocity can be better captured by including cross flow. The effects of the submergence Froude number on the free surface and streamwise velocity are also examined. The free surface significantly fluctuates at high submergence Froude number flows and the corresponding distribution of streamwise velocity profiles exhibits a trend different from that obtained for low submergence Froude number flows.

关键词： pump sump cross flow submergence Froude number Large Eddy Simulation (LES)

Application of Thermolum inescence Techniques to Mineral Exploration—Principles and Advantages

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Journal of Earth Science 2000年第2期19卷 31-35页

作者： Chen Chi-Chieu Department of Earth Sciences, national cheng kung university, Tainan, Taiwan

The phenomena of TL are connected with the defect structures of the atomic lattice of the material concerned, and hence are very sensitive to changes in defection of the country rocks status as induced by the mineralizing solution. In other words, the TL of the country rocks from the mineralized area should be quite different from that in the intact barren *** the high sensitivity as mentioned above, advantages of the application of TL techniques to the mineral exploration the easiness in accessing to proper samples, the easy preparation of samples and the quickness in sample processing all amount to convenience and economy of the techniques, indicating the high competitiveness of the TL mineral exploration method, especially during the development stage of mining operations.

关键词： application thermoluminescence mineral exploration advantages.

Longshore Current on an Equilibrium Beach

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China Ocean Engineering 1996年第2期11卷 181-192页

作者： Chang Hsien-Kuo and HsuTai-Wen’ Associate Professor, Department of Civil Engineering, national Chiao Tung university, 1001 Ta-Hsueh Rd.,Hsinchu, 300 Taiwan . Associate Professor, Department of Hydraulics and Ocean Engineering, national cheng kung university,Tainan Department of Civil Engineering National Chiao Tung University 1001 Ta-Hsueh Rd. Hsinchu 300 Taiwan Dept. of Hydr. and Ocean Engineering National Cheng Kung University Tainan Taiwan

Natural beaches tend to be concave-up rather than planar and are reasonable to be modeled by an equilibrium beach profile. A governing equation for longshore current on an equilibrium beach is derived and its analytical solution is given in this paper. Through comparisons of the present solution and field data of longshore current for a step-type beach, the present solution is found to have fairly agreeable prediction to longshore current inside the surf zone. The effects of the shape of a concave-up beach and turbulent mixing stress on longshore current inside the surf zone are discussed in the present paper.

关键词： longshore current equilibrium beach profile surf zone turbulent mixing stress

An unsupervised grid-based approach for clustering analysis

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Science China(Information Sciences) 2010年第7期53卷 1345-1357页

作者： YUE ShiHong1, WANG JeenShing2, TAO Gao1 & WANG HuaXiang1 1School of Electrical Engineering and Automation, Tianjin Key Laboratory of Process Measurement and Control, Tianjin university, Tianjin 300072, China 2Department of Electrical Engineering, national cheng kung university, Tainan 701, China School of Electrical Engineering and Automation Tianjin Key Laboratory of Process Measurement and Control Tianjin University Department of Electrical Engineering National Cheng Kung University

In recent years, the growing volume of data in numerous clustering tasks has greatly boosted the existing clustering algorithms in dealing with very large datasets. The K-means has been one of the most popular clustering algorithms because of its simplicity and easiness in application, but its effciency and effectiveness for large datasets are often unacceptable. In contrast to the K-means algorithm, most existing grid-clustering algorithms have linear time and space complexities and thus can perform well for large datasets. In this paper, we propose a grid-based partitional algorithm to overcome the drawbacks of the K-means clustering algorithm. This new algorithm is based on two major concepts: 1) maximizing the average density of a group of grids instead of minimizing the minimal square error which is applied in the K-means algorithm, and 2) using grid- clustering algorithms to thoroughly reformulate the object-driven assigning in the K-means algorithm into a new grid-driven assigning. Consequently, our proposed algorithm obtains an average speed-up about 10-100 times faster and produces better partitions than those by the K-means algorithm. Also, compared with the K-means algorithm, our proposed algorithm has ability to partition any dataset when the number of clusters is unknown. The effectiveness of our proposed algorithm has been demonstrated through successfully clustering datasets with different features in comparison with the other three typical clustering algorithms besides the K-means algorithm.

关键词： clustering grid-based algorithm K-means algorithm

A Study of the Background for the Anti-Socialist Law of 1878 under Bismarck(Abstract)

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A Study of the Background for the Anti-Socialist Law of 1878...

The Reactions of Sydnone Compounds

北京论坛（2006）文明的和谐与共同繁荣—对人类文明方式的思考

作者： WANG Chi national cheng kung university,Taiwan

Bismarck is one of the most important historical figures for historians in their study of modem German history,especially of the European Relations at the end of the 19 *** Alliance System built up by Bismarck was even called the"Bismarck System,"and this means Bismarck in his management of intemational affairs had developed his own tactics that deserves

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来源： cnki会议评论

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cnki会议

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有机化学 1993年第2期 189-191页

作者： TIEN Hsien-Ju HO Young-Shang Department of Chemistry, national cheng kung university, Tainan, Taiwan 701 Nan-Jeon Junior College of Technology, Yen Shuyi, Tainan, Taiwan 737

The duality in electronic effect of sydnone ring and the effect of delocalization of 4-substitutedgroup to sydnone ring are investigated by the nitration of 3-benzyl-4-phenylsydnone and 4-formyl-3-arylsydnones. Sydnon... 详细信息

关键词： sydnone mesoinic compounds reaction

Prediction analysis of long-term memory effect for calamity gray series

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Science China Earth Sciences 2004年第3期47卷 209-220页

作者： CHEN Zhaonan (CHEN Chaonan)1 & LI Zongyang (LEE Tzongyeang)2 1. Department of Earth Sciences, national cheng kung university, 1 Ta-Hsueh Road, Tainan 70101, Taiwan, China 2. Department of Information Management, Leader university, No. 188, Sec 5, Au-Chung Road, Tainan 70901, Taiwan, China Department of Earth Sciences National Cheng Kung University 1 Ta-Hsueh Road Tainan 70101 Taiwan Department of Information Management Leader University No. 188 Sec 5 Au-Chung Road Tainan 70901 Taiwan

It is adequate to use the gray theory for modeling and forecasting short-term calamity series. The forecast of calamity gray series is equivalent to predicting an extraordinary event in nature. In order to look for the regularity, the calamity date series, created from the threshold for a fixed time-interval series, are studied. In this paper, the Hurst exponent is applied to defining the long-term memory effect of the simulated calamity series, and is tested for the feasibility of using it as pre-requisite information before the gray modeling and forecasting. Based on the fractional Brownian motion (fBm) model, the time series with a definite length or quantity of data are derived assuming that various kinds of memory effect exist. Different threshold values are defined to yield or to analogize the calamity date series that are required in the prediction of the gray calamity events. After case study, both of the simulated and real seismic data show that the Hurst exponents are greater than 0.5 and, therefore, indicate that the long-term memory ef-fect exists. The correlation between the Hurst exponent and the gray modeling parameter, a, provides criteria for the classification of the forecast.

关键词： gray theory, calamity series, Hurst exponent, long-term memory effect, fractional Brownian motion.

VARIATION OF WATER DEPTH AND MANNING'S ROUGHNESS n DUE TO RIVER MEANDERING IN SUBCRITICAL FLOW REGIME

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International Journal of Sediment Research 2001年第1期16卷 69-79页

作者： Chin-Kun HUANG and Chang-Ling LIU Assistant professor, Department of Hydraulics & Ocean Engineering, national cheng kung university, Tainan,70101, Taiwan, China Professor, Department of Hydraulics & Ocean Engineering, national cheng kung university, Tai Department of Hydraulics & Ocean Engineering National Cheng Kung University Tainan70101 Taiwan China Department of Hydraulics & Ocean Engineering National Cheng Kung University Tainan 70101Taiwan China

This paper aims to study the variation of water depth H and Manning’s n due to the meandering of a river. It is found from experimental results that the increase in H and n is related to the sinuosities and the Froude numbers measured in the straight reach. In this study, the channel form is generated from sine-generated curve with ten different sinuosities. The results of this analysis can be applied to both cases of fixed bed and mobile bed.

关键词： Water depth Manning’s roughness Meandering

An Implicit Pressure Correction Method for Incompressible Navier-Stokes Equations

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An Implicit Pressure Correction Method for Incompressible Na...