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A High-Accuracy Finite Difference Scheme for Solving Reaction-Convection-Diffusion Problems with a Small Diffusivity

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Advances in Applied Mathematics and Mechanics 2014年第5期6卷 637-662页

作者： Po-Wen hsieh Suh-Yuh Yang Cheng-Shu You Department of Applied Mathematics Chung Yuan Christian UniversityJhongli CityTaoyuan County 32023Taiwan Department of Mathematics National Central UniversityJhongli CityTaoyuan County 32001Taiwan

This paper is devoted to a new high-accuracy finite difference scheme for solving reaction-convection-diffusion problems with a small diffusivityε.With a novel treatment for the reaction term,we first derive a difference scheme of accuracy O(ε^(2)h+εh^(2)+h^(3))for the 1-D *** the alternating direction technique,we then extend the scheme to the 2-D case on a nine-point *** apply the high-accuracy finite difference scheme to solve the 2-D steady incompressible Navier-Stokes equations in the stream function-vorticity *** examples are given to illustrate the effectiveness of the proposed difference *** made with some high-order compact difference schemes show that the newly proposed scheme can achieve good accuracy with a better stability。

关键词： Reaction-convection-diffusion equation incompressible Navier-Stokes equations boundary layer interior layer finite difference scheme

KELVIN-HELMHOLTZ STABILITY AND TWO-PHASE FLOW

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Acta Mathematica Scientia 1989年第2期9卷 189-197页

作者： D.Y.hsieh Division of Appl.Math. Brown Univ.Providence RI 02912 USA

The ill-posedness of the two-phase flow problems is explicitly related to the Kelvin-Helmholtz instability of two compressible fluid Layers. A long wavelength formulation of the Kelvin-Helmholtz problem is derived. Va... 详细信息

关键词：二相流 Kelvin-Helmholtz稳定性

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THE PHOTOCHEMICAL SYNTHESIS OF THE PYRIDINE ADDUCT OF TETRAPHENYLPORPHYRINATORHODIUM(Ⅱ)AND THE MECHANISM OF PHOTOCHEMICAL REACTION

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Chinese Chemical Letters 1991年第4期2卷 279-280页

作者： A.K.hsieh Department of Chemistry National University of Singapore

A new rhodium(Ⅱ)porphyrin complex was isolated by chromatography from the photochemical reac- tion of(μ—tetraphenylporphyrinato)bis[dicarbonylrhodium(Ⅰ)]with pyridine in benzene and has been charac- *** the result... 详细信息

关键词： TPP THE PHOTOCHEMICAL SYNTHESIS OF THE PYRIDINE ADDUCT OF TETRAPHENYLPORPHYRINATORHODIUM AND THE MECHANISM OF PHOTOCHEMICAL REACTION

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Numerical study of the effects of check dams on erosion and sedimentation in the Pachang River

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International Journal of Sediment Research 2013年第3期28卷 304-315页

作者： Hui-ming hsieh Ching-ruey LUO Jinn-chuang YANG Rou-fei CHEN Department of Computer Science and Multimedia Design Taiwan Shoufu University Department of Civil Engineering National Chi-Nan University Dept.of Civil Engineering National Chiayio Tung University Department of Geology Chinese Culture University

Scouring and deposition processes resulting from variable rainfall and typhoon occurrence in tropical climatic conditions induce significant changes in the riverbeds of *** the Pachang River of western Taiwan,severe damage occurs during typhoons due to large and sudden variations in discharge,erosion,sediment transport and *** order to simulate this process,the NETSTARS numerical modeling tool was used in the present *** influence of existing and planned check dam structures on flow control was also analyzed to determine their capacity to resist river erosion or to not be buried beneath *** only does the modeling tool allow calculation of the erosion-deposition behavior at the scale of the whole river,but it also provides local determination of the optimum location and characteristics such as foundation depth and lateral encroachment of future check *** results of a 10-year,long-term modeling simulation in terms of riverbed stability and scouring potential thus provide insights about unsafe future behavior at 4 *** numerical model provides a better general understanding and useful information for the optimal prevention of both the scouring damage and the burial related to sediment deposition with large changes in discharge and sediment transport.

关键词： NETSTARS model River bed erosion Check dam Pachang River

Characterization of horseshoe vortex in a developing scour hole at a cylindrical bridge pier

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International Journal of Sediment Research 2019年第2期34卷 118-124页

作者： Dawei Guan Yee-Meng Chiew Maoxing Wei Shih-Chun hsieh College of Harbour Coastal and Offshore EngineeringHohai University School of Civil and Environmental Engineering Nanyang Technological University

Since local scour at bridge piers in rivers and estuaries is a major cause of bridge failure,estimation of the maximum local scour depth is of great importance to hydraulic and coastal *** numerous studies that focus on scour-depth prediction have been done and published,understanding of the flow and turbulence characteristics of the horseshoe vortex that drives the scour mechanism in a developing scour hole still is *** study aims to quantify the detailed turbulent flow field in a developing clear-water scour hole at a circular pier using Particle Image Velocimetry(PIV).The distributions of velocity fields,turbulence intensities,and Reynolds shear stresses of the horseshoe vortex that form in front of the pier at different scour stages(t = 0,0.5,1,12,24,and 48 h)are presented in this *** scour development,the horseshoe vortex system was found to evolve from one initially small vortex to three *** strength and size of the main vortex are found to increase with increasing scour *** regions of both the maximum turbulence intensity and Reynolds shear stress are found to form at a location upstream of the main vortex,where the large turbulent eddies have the highest possibility of *** from this study not only provide new insight into the complex flow-sediment interaction at bridge piers,but also provide valuable experimental databases for advanced numerical simulations.

关键词： Sediment transport Scour Bridge pier PIV Horseshoe vortex Turbulence Scour hole

Human-micromanipulator cooperation using a variable admittance controller

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Science China(Information Sciences) 2019年第5期62卷 14-16页

作者： hsieh-Yu LI Theshani NURADHA Sebaratnam Alex XAVIER U-Xuan TAN Pillar of Engineering Product Development Singapore University of Technology and Design Department of Electronic and Telecommunication Faculty of Engineering University of Moratuwa

Dear editor,Micro-scale operations, such as microsurgery [1]and micro-devices assembly [2], have been gaining importance among different industries. However,it is challenging to execute these operations owing to the accuracy requirements of the operation which are close to the limit of the human hand accuracy. For example, microsurgery is a diffi-

关键词： Human-micromanipulator cooperation using a variable admittance controller

Roux-en-Y reconstruction does not require gastric decompression after radical distal gastrectomy

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World Journal of Gastroenterology 2012年第3期18卷 251-256页

作者： Cheng-Jueng Chen Tsang-Pai Liu Jyh-Cherng Yu Sheng-Der Hsua Tsai-Yuan hsieh Heng-Cheng Chu Chung-Bao hsieh Teng-Wei Chen, De-Chuan Chan Division of General Surgery Tri-Service General Hospital National Defense Medical Center 11490 Taipei Taiwan China Department of Surgery Mackay Memorial Hospital Mackay Medicine Nursing and Management College Peitou 10449 Taipei Taiwan China Division of Gastroenterology Tri-Service General Hospital National Defense Medical Center 11490 Taipei Taiwan China

AIM: To determine whether routine nasogastric (NG) decompression benefitted patients undergoing radical gastric surgery. METHODS: Between January 1998 and December 2008, 519 patients who underwent distal gastrectomy for gastric cancer were retrospectively divided into 2 time-period cohorts; those treated with Billroth Ⅱ (BⅡ) reconstruction in the first 6 years and those with Roux-en-Y (RY) reconstruction in the last 5 years. In the latter group, the patients were further divided into 2 subgroups; with and without nasogastric ***: Postoperatively, there were no significant differences in the number of anastomotic leaks between the 3 groups. In the tubeless RY group, time to semiliquid diet was significantly shorter than in the other 2 groups (4.4 d ± 1.4 d vs 7.2 d ± 1.3 d and 5.9 d ± 1.2 d, P = 0.005). The length of postoperative stay was significantly increased in patients with BⅡ reconstruction compared with patients with RY reconstruction with/without NG decompression (15.4 d ± 4.3 d in BⅡ group vs 12.6 d ± 3.1 d in decompressed RY and 11.4 d ± 3.4 d in the tubeless RY group, P = 0.035). The postoperative pneumonia rate was lowest in the tubeless group and highest in the BⅡ group (1.4% vs 4.6%, P = 0.01). Severe sore throat was noted in 59 (20.7%) members of the BⅡ group, 18 (17.4%) members of the decompressed RY group and 6 (4.2%) members of the tubeless RY group. Fewer patients in the tubeless group complained of severe sore throat (P = 0.001). CONCLUSION: This study provides support for abandoning routine NG decompression in patients undergoing subtotal gastrectomy with Roux-en-Y gastrojejunostomy.

关键词： Nasogastric decompression Billroth Ⅱ gas- trojejunostomy Roux-en-Y gastrojejunostomy Radical distal gastrectomy Gastric cancer

Relationship of Brazing Microstructure and Ti-Cu-Ni Phase Diagram

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材料科学与工程（中英文B版） 2017年第4期7卷 142-148页

作者： Ming-Chi Ho Pei Jen Lo Wei-liang Liu Ker-Chang hsieh Department of Materials and Optoelectronic Science National Sun Yat-Sen University Kaohsiung 804 Taiwan Metal Industries Research & Development Center Kaohsiung 804 Taiwan

The Microstructure of Zr-Based Bulk Metallic Glass and Glass Matrix Composite

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材料科学与工程（中英文B版） 2017年第4期7卷 135-141页

作者： Min-Chi Yeh Pei Jen Lo Wei-liang Liu Ker-Chang hsieh Department of Materials and Optoelectronic Science National Sun Yat-Sen University Kaohsiung 804 Taiwan Metal Industries Research & Development Center Kaohsiung 804 Taiwan