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Numerical simulation of tidal current and erosion and sedimentation in the Yangshan deep-water harbor of Shanghai

International Journal of Sediment Research 2009年第3期24卷 287-298页

作者： ZUO Shu-Hua1, ZHANG Ning-Chuan2. LI Bei3, ZHANG Zheng4, and ZHU Zhi-Xia51 Ph.D candidate, state key {2. of Coastal and Offshore Engineering, Dalian university of technology, Dalian 11602., china key {2. of Engineering Sediment of Ministry of Communications, tianjin Research Institute of Water Transport Engineering, tianjin 300456, china. 2.Dr., Prof., state key {2. of Coastal and Offshore Engineering, Dalian university of technology, Dalian 11602., china 3 Research Scientist, key {2. of Engineering Sediment of Ministry of Communications, tianjin Research Institute of Water Transport Engineering, tianjin 300456, china 4 Research Scientist, key {2. of Engineering Sediment of Ministry of Communications, tianjin Research Institute of Water Transport Engineering, tianjin 300456, china 5 Dr., Prof., Department of Harbor & Coastal Engineering, Shanghai Jiaotong university, Shanghai 2.0030, china [a] Ph.D candidate state key {2. of Coastal and Offshore Engineering Dalian university of technology Dalian 11602. china key laboratory of Engineering Sediment of Ministry of Communications tianjin Research Institute of Water Transport Engineering tianjin 300456 china [b] Dr. Prof. state key {2. of Coastal and Offshore Engineering Dalian university of technology Dalian 11602. china [c] Research Scientist key laboratory of Engineering Sediment of Ministry of Communications tianjin Research Institute of Water Transport Engineering tianjin 300456 china [d] Research Scientist key laboratory of Engineering Sediment of Ministry of Communications tianjin Research Institute of Water Transport Engineering tianjin 300456 china [e] Dr. Prof. Department of Harbor & Coastal Engineering Shanghai Jiaotong university Shanghai 2.0030 china

Yangshan near-shore sea area is the multi-island and multi-channel area with strong flow velocity and high suspended sediment concentration. Based on the characteristics of tidal currents, waves, and sediment in the Yangshan area, a two-dimensional numerical model of tidal currents, sediment transport, and sea bed deformation is developed. In the model, the effects of tidal currents and wind waves on sediment transport are considered. According to characteristics of the study area, unstructured grids are applied to fit the boundaries of the near-shore sea area. The results show that the calculated values are in good agreement with the measured data. The field of tidal currents, suspended sediment concentrations, and the deformation of the seabed can be successfully simulated.

关键词： Yangshan deep-water port Tidal currents Sediment Suspended sediment concentration Seabed deformation Numerical simulation

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A new relative radiometric consistency processing method for change detection based on wavelet transform and a low-pass filter

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Science china(Technological Sciences) 2010年第S1期53卷 7-14页

作者： SUN KaiMin1,SUI HaiGang1,2.LI DeRen1 & XU Chuan1,2.1 state key {2. of Information Engineering in Surveying,Mapping and Remote Sensing,Wuhan university,Wuhan 430079,china 2.state key {2. of Subtropical Building Science,South china university of technology,Guangzhou 510640,china 1. state key {2. of Information Engineering in Surveying Mapping and Remote Sensing Wuhan University Wuhan 430079 China 2. state key {2. of Subtropical Building Science South China University of Technology Guangzhou 510640 China

The research purpose of this paper is to show the limitations of the existing radiometric normalization approaches and their disadvantages in change detection of artificial objects by comparing the existing approaches,on the basis of which a preprocessing approach to radiometric consistency,based on wavelet transform and a spatial low-pass filter,has been *** approach first separates the high frequency information and low frequency information by wavelet ***,the processing of relative radiometric consistency based on a low-pass filter is conducted on the low frequency *** processing,an inverse wavelet transform is conducted to obtain the results *** experimental results show that this approach can substantially reduce the influence on change detection of linear or nonlinear radiometric differences in multi-temporal images.

关键词： wavelet transform radiometric normalization low-pass filter change detection

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Analysis of Material Removal in Alumina Ceramic Honing

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厦门大学学报（自然科学版） 2002年第S1期41卷 51-52页

作者： YU Ai-bing 1, XU Yan-shen 1, CHEN Si-fu 1, LIN Bin 1, TIAN Xin-li 2.(1. The state Education Ministry key {2. of High Temperature Structure Ceramics & Machining technology for Engineering Ceramics, tianjin university, tianjin 300072, china 2. Institute of Armored Force, Beijing 100072. china)

The removal mechanism is of importance to the grinding of hard and brittle ceramic materials. It is more suitable to analyze the material removal during ceramics honing processes by means of indention fracture approach. There are two honing characteristics different from grinding, the honing incidental tensile stresses and the crosshatch pattern. The stresses may influence material removal of brittle ceramics with lower tensile strength. In addition, the criss-cross cutting pattern on a bore known as crosshatch may also have its effect on the material removal of ceramics. The material removal of alumina is analyzed on the basis of honing characteristics, honing incidental tensile stresses and crosshatch pattern. By means of indentation fracture mechanics of brittle solids, the theoretical analysis of stress intensity factor and the crack response prove that honing incidental tensile stresses can increase the stress intensity factor of honing cracks and decrease the grinding stresses. So, the fracture criterion for crack propagation can be met easily. Therfore, it is possible to machine ceramic materials with small grinding forces in honing processes. The alumina honing experiments show that material at crosshatch intersecting point is removed by way of chipping which is similar to the edge-crumbled of ceramics. For brittle ceramics with lower tensile strength, such as Al 2. 3, SiO 2. the influences of the honing incidental tensile stresses and the crosshatch pattern on material removal are bigger than that of ceramics with relative higher toughness, such as ZrO 2.and Si 3N 4. Hence, the honing of Al 2. 3, SiO 2. is superior in cutting ability to the grinding. The large stock removal of brittle ceramic materials can be obtained through higher honing pressures. The increase in honing pressures can increase intensity factor of honing cracks, decrease the grinding stresses, and remarkably improve material removal rate. The researches show that honing is an efficient bor

关键词： material removal honing ceramics stresses

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Preparation of Oriented Barium Titanate Thin Films by Combination of Electrophoretic Deposition with Hydrothermal Treatment

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Journal of Materials Science & technology 2010年第11期26卷 996-1000页

作者： Lihong Xue and Youwei Yan state key {2. of Materials Processing and Die and Mould technology,Huazhong university of Science and technology,Wuhan 430074,china [a] state key {2. of Materials Processing and Die and Mould technology Huazhong university of Science and technology Wuhan 430074 china

Highly oriented barium titanate （BaTiO 3） thin films on Pt substrate were fabricated by combination of electrophoretic deposition with hydrothermal *** structure and morphology of thin films were characterized by X-ray diffraction and field-emission scanning electron *** is found that the titania precursor film,Ba（OH）2.concentration and hydrothermal temperature play crucial roles in the film morphology and *** BaTiO3 thin films with highly （110） preferred orientation can be formed on polycrystalline Pt substrate by appropriate adjustment of the reaction *** orientation parameter f of highly oriented BaTiO3 films was up to *** films exhibited a smooth and crack-free surface and remained in the layered *** situ topotactic transformation and dissolution-crystallization mechanisms were proposed to explain the morphology and orientation of BaTiO3 films during hydrothermal treatment.

关键词： Barium titanate Preferred orientation Electrophoretic deposition Hydrothermal treatment

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Genetic polymorphisms of milk epithelial mucin of yaks

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Progress in Natural Science:Materials International 2006年第11期16卷 1222-1226页

作者： ZHENG Yucai~1, ZHAO Xingbo~2.*, JIN Suyu~1, PENG Xianwen~1 and BAI Wenlin~1 (1. College of Life Science and technology, Southwest university for Nationalities, Chengdu 610041, {2. 2. state key laboratory for Agrobiotechnology and Ministry of Agriculture key laboratory of Animal Genetics, Breeding and Reproduction, {2. Agricultural university, Beijing 100094, {2.) [a]College of Life Science and technology Southwest University for Nationalities Chengdu China [b]state key {2. for Agrobiotechnology and Ministry of Agriculture key {2. of Animal Genetics Breeding and Reproduction China Agricultural University Beijing China

Milk epithelial mucin (MUC1) of yaks was separated by SDS-polyacrylamide gel electrophoresis. A total of nine types of MUC1 were revealed in 42. yaks from five yak breeds including Maiwa yak, Jiulong yak, Tianzhu white yak, Qinghai yak and Tibetan yak. The molecular weights of MUC1 are from 163 kD to 2.8 kD, most of which are larger than those of bovine. Population genetic analysis shows that the gene frequency and genotype frequency of yak MUC1 differ among breeds, with relatively high gene heterozygosity. The five yak breeds studied fall into two groups according to their milk MUC1 gene frequency, suggesting that milk MUC1 exhibits specificities for local yak groups.

关键词： yak milk genetic polymorphism MUC1.

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Degradation of 4-chlorophenol in aqueous solution by γ-radiation and ozone oxidation

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Science china Chemistry 2006年第2期49卷 186-192页

作者： HU Jun1, WANG Jianlong1,2.& CHEN Rong1 1. laboratory of Environmental technology, Institute of Nuclear Energy technology, Tsinghua university, Beijing 100084, china 2. state key Joint laboratory of Environmental Simulation and Pollution Control, Tsinghua university, Beijing 100084, china Correspondence should be addressed to Wang Jianlong 1. laboratory of Environmental technology Institute of Nuclear Energy Technology Tsinghua University Beijing 100084 China 2. state key Joint {2. of Environmental Simulation and Pollution Control Tsinghua University Beijing 100084 China

The degradation of 4-chlorophenol (4-CP) by using gamma rays generated by a 60Co source in the presence of O3 was investigated. The radiolysis of 4-CP and the kinetics of 4-CP min-eralization were analyzed based on the determination of total organic carbon (TOC). The influence of initial 4-CP concentration and the free radicals scavengers (such as NaHCO3 and t-butanol) on the 4-CP degradation was also studied. The results showed that when the radiation rate was 336 Gy·min?1, 4-chlorophenol at concentration of 10 mg·L?1 could be completely degraded at the radiation dose of 2.kGy. The degradation of 4-chlorophenol could be described by a first-order reaction model, the rate constant of 4-CP degradation by combined ozonation and radiation was 0.1016 min?1, which was 2.4 times higher than the sum of radiation (0.02.4 min?1) and ozonation (0.0137 min?1). It re-vealed that the combination of radiation and ozonation resulted in synergistic effect, which can re-markably increase the degradation efficiency of 4-CP.

关键词： radiolysis, 4-chlorophenol, priority pollutant, degradation, O3, synergistic effect, kinetics.

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Practical conditions of signal space alignment for generalized MIMO Y channel

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Science china(Information Sciences) 2012年第10期55卷 2171-2182页

作者： SHE JiaJu 1,2.CHEN ShanZhi 1,2.HU Bo 1,WANG YingMin 2.& SU Xin 2.1 state key {2. of Networking and Switching technology,Beijing university of Posts and Telecommunications,Beijing 100876,china 2.state key {2. of Wireless Mobile Communications,china Academy of Telecommunications technology,Beijing 100191,china 1. state key {2. of Networking and Switching technology Beijing University of Posts and Telecommunications Beijing 100876 China2. State Key Laboratory of Wireless Mobile Communications China Academy of Telecommunications Technology Beijing 100191 China

This paper proposes a generalization for applications of signal space alignment(SSA) in a generalized multiple input multiple output(MIMO) Y channel with K(K 2. nodes and an intermediate *** on that generalization,a method is introduced to determine the practical conditions for *** first study the generalized MIMO Y channel model with general signal demands;then,the degrees of freedom(DoF) achieved are given and are proved using *** SSA could decrease the number of antennas at the relay,it places new restrictions on the numbers of antennas at the *** then introduce a method to compare the models with and without SSA network coding(SSA-NC),mainly from the perspective of the total number of antennas *** results show that if each node must be able to exchange signals with all others,the model with SSA will definitely use more antennas to supply the same DoF,when K > *** it is not necessary for every node to exchange signals with all others,the comparison can still be made by using the method introduced *** a result,the conditions under which SSA-NC is needed are presented.

关键词： Signal space alignment MIMO Y channel degrees of freedom number of antennas

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A modified method for simulating non-stationary multi-point earthquake ground motion

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Earthquake Engineering and Engineering Vibration 2010年第2期9卷 201-211页

作者： Li Minggao,Li Xin and Zhou Jing state key {2. of Coastal and Offshore Engineering,Dalian university of technology,Dalian 11602.,china state key {2. of Coastal and Offshore Engineering Dalian University of Technology Dalian 116024 China

A spectral-representation-based algorithm is proposed to simulate non-stationary and stochastic processes with evolutionary power,according to a prescribed non-stationary cross-spectral density matrix. Non-stationary multi-point seismic ground motions at different locations on the ground surface are generated for use in engineering applications. First,a modified iterative procedure is used to generate uniformly modulated non-stationary ground motion time histories which are compatible with the prescribed power spectrum. Then,ground motion time histories are modeled as a non-stationary stochastic process with amplitude and frequency modulation. The characteristic frequency and damping ratio of the Clough-Penzien acceleration spectrum are considered as a function of time in order to study the frequency time variation. Finally,two numerical examples are presented to validate the efficiency of the proposed method,and the results show that this method can be effectively applied to the dynamic seismic analysis of long and large scale structures.

关键词： multi-support excitation spatial correlation power spectrum-compatibility non-stationary ground motion simulation

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A Creep Equation Based on Thermal Activation

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International Journal of Minerals,Metallurgy and Materials 1998年第1期12卷 44-46页

作者： Jiyue Sun Guoliang Chen (state key {2. for Advanced Metals and Materials, university of Science and technology Beijing, Beijing 100083, china) state key {2. for Advanced Metals and Materials University of Science and Technology Beijing Beijing 100083 China

The creep equation proposed in so called θ projection concept is developed in the concept of thermal activation of creep. The measured creep curves of A2.6 alloy are fitted by the equation. The activation energy in theequation is evaluated, and creep rupture lives are predicted. The results are confirmed by creep tests of up to 13years.

关键词： creep creep curve equation creep rupture life A2.6 superalloy

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Fuzzy tracking control design for hypersonic vehicles via T-S model

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Science china(Information Sciences) 2011年第3期54卷 521-528页

作者： GAO DaoXiang 1 & SUN ZengQi 2.1 School of technology, Beijing Forestry university, Beijing 100083, {2. 2.state key laboratory of Intelligent technology and System, Department of Computer Science and technology, Tsinghua university, Beijing 100084, {2. 1. School of technology Beijing Forestry University Beijing 100083 China2. State Key Laboratory of Intelligent Technology and System Department of Computer Science and Technology Tsinghua University Beijing 100084 China

The main focus of this paper is on designing a T-S fuzzy controller for the hypersonic vehicle. The longitudinal dynamics of the vehicle are studied using time-scale decomposition to reduce the complexity of T-S modeling. The dynamic inversion with PI control technique is applied for the slow dynamics to derive the flight path angle command and throttle setting by taking the pilot altitude and velocity command as its inputs. The T-S fuzzy controller is designed for the fast dynamics to derive the elevator deflection to track the flight path angle command. The discrepancy between the T-S model and real vehicle model is considered by using sliding mode control for the system stability. Simulation results are included to show the effectiveness of the controller.

关键词： fuzzy control T-S model sliding mode control hypersonic vehicle

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