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Parametric Geometric Model and Hydrodynamic Shape Optimization of A Flying-Wing Structure Underwater Glider

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China Ocean Engineering 2017年第6期31卷 709-715页

作者： wang zhen-yu yu Jian-cheng ZHANG Ai-qun wang Ya-xing ZHAO Wen-tao State Key Laboratory of Robotics Shenyang Institute of Automation Chinese Academy of Sciences Shenyang 110016 China University of Chinese Academy of Sciences Beijing 100049 China

Combining high precision numerical analysis methods with optimization algorithms to make a systematic exploration of a design space has become an important topic in the modern design methods. During the design process of an underwater glider＇s flying-wing structure, a surrogate model is introduced to decrease the computation time for a high precision analysis. By these means, the contradiction between precision and efficiency is solved effectively. Based on the parametric geometry modeling, mesh generation and computational fluid dynamics analysis, a surrogate model is constructed by adopting the design of experiment （DOE） theory to solve the multi-objects design optimization problem of the underwater glider. The procedure of a surrogate model construction is presented, and the Gaussian kernel function is specifically discussed. The Particle Swarm Optimization （PSO） algorithm is applied to hydrodynamic design optimization. The hydrodynamic performance of the optimized flying-wing structure underwater glider increases by 9.1%.

关键词： surrogate model underwater glider design optimization blended-wing-body

Influence of excavation schemes on slope stability: A DEM study

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Journal of Mountain Science 2020年第6期17卷 1509-1522页

作者： wang zhen-yu GU Dong-ming ZHANG Wen-gang Key Laboratory of New Technology for Construction of Cities in Mountain Area Chongqing UniversityChongqing 400045China School of Civil Engineering Chongqing UniversityChongqing 400045China National Joint Engineering Research Center of Geohazards Prevention in the Reservoir Areas Chongqing UniversityChongqing 400045China

Slope failure due to improper excavation is one of common engineering disasters in *** explore the failure mechanism of soil slope induced by toe excavation,especially to investigate the influence of excavation unloading path and rate on slope stability,a numerical slope model was built via particle flow code PFC2 *** development of crack and strain during excavation were obtained and used to evaluate the deformation ***,excavation types representing different unloading paths and rates were compared in terms of crack number and strain *** indicate that crack number and strain level induced by horizontal column excavation are much greater than those of vertical column excavation and oblique *** crack number and strain level increase with excavation unloading ***,the feasibility of taking the average strain of slope surface and the average value of maximum strain along monitoring lines to represent the global deformation characteristics were *** study can provide a theoretical guidance for slope monitoring and preliminary optimal selection of excavation scheme in the design and construction of slope engineering.

关键词： Slope toe excavation Unloading path Unloading rate Strain distribution Slope stability Discrete element method

Analysis of bacterial community structures in two sewage treatment plants with different sludge properties and treatment performance by nested PCR-DGGE method

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Journal of Environmental Sciences 2007年第1期19卷 60-66页

作者： LIU Xin-chun ZHANG yu YANG Min wang zhen-yu LV Wen-zhou State Key Laboratory of Environmental Aquatic Chemistry Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beifing 100085 China

The bacterial community structures in two sewage treatment plants with different processes and performance were investigated by denaturing gradient gel electrophoresis （DGGE） of nested polymerase chain reaction （nested PCR） amplified 16S rRNA gene fragments with group-specific primers. Samples of raw sewage and treated effluents were amplified using the whole-cell PCR method, and the activated sludge samples were amplified using the extracted genomic DNA before the PCR products were loaded on the same DGGE gel for bacterial community analysis. Ammonia-oxidizing bacterial and actinomycetic community analysis were also carried out to investigate the relationship between specific population structures and system or sludge performance. The two plants demonstrated a similarity in bacterial community structures of raw sewage and activated sludge, but they had different effluent populations. Many dominant bacterial populations of raw sewage did not appear in the activated sludge samples, suggesting that the dominant bacterial populations in raw sewage might not play an important role during wastewater treatment. Although the two plants had different sludge properties in terms of settleability and foam forming ability, they demonstrated similar actinomycetic community structures. For activated sludge with bad settling performance, the treated water presented a similar DGGE pattern with that of activated sludge, indicating the nonselective washout of bacteria from the system. The plant with better ammonium removal efficiency showed higher ammonia-oxidizing bacteria species richness. Analysis of sequencing results showed that the major populations in raw sewage were uncultured bacterium, while in activated sludge the predominant populations were beta proteobacteria.

关键词： activated sludge wastewater treatment sewage community analysis PCR-DGGE

On the efficient search of punctured convolutional codes with simulated annealing algorithm

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The Journal of China Universities of Posts and Telecommunications 2014年第2期21卷 69-74,82页

作者： ZOU Wei-xia wang zhen-yu wang Gui-ye DU Guang-long GAO Ying Key Laboratory of Wireless Universal Communications Beijing University of Posts and Telecommunications School of Electronic Engineering Beijing University of Posts and Telecommunications

Punctured convolution codes （PCCs） have a lot of applications in modem communication system. The efficient way to search for best PCCs with longer constraint lengths is desired since the complexity of exhaustive search becomes unacceptable. An efficient search method to find PCCs is proposed and simulated. At first, PCCs＇ searching problem is turned into an optimization problem through analysis of PCCs＇ judging criteria, and the inefficiency to use pattern search （PS） for many local optimums is pointed out. The simulated annealing （SA） is adapted to the non-convex optimization problem to find best PCCs with low complexity. Simulation indicates that SA performs very well both in complexity and success ratio, and PCCs with memories varying from 9 to 12 and rates varying from 2/3 to 4/5 searched by SA are presented.

关键词： PCCs optimization problem pattern search simulated annealing

Cancellation of nonlinear distortion based on integration of FCM clustering algorithm and adaptive-two-stage linear approximation

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The Journal of China Universities of Posts and Telecommunications 2014年第3期21卷 18-22页

作者： wang Gui-ye ZOU Wei-xia wang zhen-yu DU Guang-long GAO Ying Key laboratory of wireless universal communications Beijing University of Posts and Telecommunications School of Electronic Engineering Beijing University of Posts and Telecommunications

A hybrid system of the fuzzy c-means （FCM） clustering algorithm and adaptive-two-stage linear approximation was presented for nonlinear distortion cancellation of radio frequency （RF） power amplifier （PA）. This mechanism can effectively eliminate noise, adaptively model PA＇s instantaneous change, and efficiently correct nonlinear distortion. This article puts forward the FCM clustering algorithm for clustering received signals to eliminate white noise, and then uses the adaptive-two-stage linear approximation to fit the inverse function of the amplitude＇s and phase＇s nonlinear mapping during the training phase. Parameters of the linear function and similarity function are trained using the gradient-descent and minimum mean-square error criteria. The proposed approach＇s training results is directly employed to eliminate sampling signal＇s nonlinear distortion. This hybrid method is realized easier than the multi-segment linear approximation and could reduce the received signal＇s bit error rate （BER） more efficiently.

关键词： PA nonlinear distortion cancellation FCM clustering algorithm similarity function adaptive-two-stage linear approximation

The characterization of acid and pepsin soluble collagen from ovine bones (Ujumuqin sheep)

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Journal of Integrative Agriculture 2018年第3期17卷 704-711页

作者： GAO Ling-ling wang zhen-yu LI zheng ZHANG Cai-xia ZHANG De-quan Institute of Food Science and Technology Chinese Academy of Agricultural Sciences/Key Laboratory of Agro-products Processing Ministry of Agriculture

Ovine bones are the major by-products after slaughtered. The present study was conducted to extract and characterize acid soluble collagens （ASC） and pepsin soluble collagens （PSC） from ovine bones （Ujumuqin sheep）. Ovine bones collagen were identified by sodium dodecyl sulfate-polyacrylamide gel electrophoresis （SDS-PAGE） and liquid chromatography-tan- dem mass spectrometry （LC-MS/MS） as type I collagen. The results of Fourier transform infrared （FTIR） spectra analysis testified the existence of triple superhelical structure in both ASC and PSC, showing pepsin did not disrupt the triple helical structure of ovine bones collagen. Glycine, accounting for one-third of total amino acids, was the major amino acid for ovine bones collagen. Higher imino acid content was responsible for higher thermal denaturation temperature of ovine bones collagen compared to fish collagens. The isoelectric point of ASC was lower than PSC due to the higher content of acidic amino acids. Therefore, this study provides the potential reference for collagen extraction and application of ovine bones by-procduct.

关键词： ovine bones collagen characterization amino acid composition denaturation temperature

Biodegradation of Crude Oil in Contaminated Soils by Free and Immobilized Microorganisms

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Pedosphere 2012年第5期22卷 717-725页

作者： wang zhen-yu XU Ying wang Hao-yun ZHAO Jian GAO Dong-Mei LI Feng-Min B. XING College of Environmental Science and Engineering Ocean University of China Qingdao 266100 (China) College of Animal Science and Veterinary Medicine Qingdao Agricultural University Qingdao 266109 (China) Chemical and Mineral Metal Material Testing Center Tianjin Entry-Exit Inspection and Quarantine Bureau Tianjin 300456 (China) Department of Plant Soil and Insect Sciences University of Massachusetts Amherst MA 01003 (USA)

The efficiencies of free and immobilized bacterial cultures of petroleum hydrocarbon degraders were evaluated and compared in this study. Hydrocarbon-degrading microbial communities with high tolerance to and high degrading ability of crude oil were obtained from the soil contaminated with crude oil in the Yellow River Delta. Then, the microbial cells were immobilized in sodium alginate （SA） beads and sodium Mginate-diatomite （SAD） beads. The biodegradation of crude oil in soil by immobilized cells was compared with that by free cells at three inoculation concentrations, 1× 104 colony forming units （cfu） kg-^（-1）（low concentration, L）, 5 × 104 cfu kg^（-1）（medium concentration, M）, and 1× 105 cfu kg^（-1）（high concentration, H）. At 20 d after inoculation, the maximum degradation rate in the immobilized systems reached 29.8% （SAD-M）, significantly higher （P 〈 0.05） than that of the free cells （21.1%）, and the SAD beads showed greater degradation than the SA beads. Moreover, both microbial populations and total microbial activity reached significantly higher level （P 〈 0.05） in the immobilized systems than free cell systems at a same initial inoculation amount. The scanning electronic microscope （SEM） images also confirmed the advantages of the immobilized microstructure of SAD beads. The enhanced degradation and bacterial growth in the SAD beads indicated the high potential of SAD beads as an effective option for bioremediation of crude oil-contaminated soils in the Yellow River Delta.

关键词： bacterial growth degradation rate hydrocarbon degraders immobilized cells sodium alginate-diatomite beads

Changes of Intramuscular Fat Composition,Lipid Oxidation and Lipase Activity in Biceps femoris and Semimembranosus of Xuanwei Ham During Controlled Salting Stages

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Journal of Integrative Agriculture 2013年第11期12卷 1993-2001页

作者： wang zhen-yu GAO Xiao-guang ZHANG Ji-hong ZHANG De-quan MA Chang-wei Institute of Agro-Products Processing Science and Technology Chinese Academy of Agricultural Sciences/Key Laboratory of Agro-ProductsProcessingMinistry of Agriculture College of Food Science and Nutritional Engineering China Agricultural University Department of Food Science Cornell University

Fatty acid composition of neutral lipids （NLs）, phospholipids （PLs） and free fatty acids （FFAs） from intramuscular fat （IMF）, lipid oxidation and lipase activity in muscle Semimembranosus （SM） and msucle Biceps femoris （BF） of dry-cured Xuanwei ham during the 90-d salting stages were analysed. The salt content increased from 0.34 to 3.52%in BF and from 0.10 to 5.42%in SM during the 90 d salting stage, respectively. PLs of IMF in both BF and SM decreased 54.70%（P〈0.001） and 34.64%（P〈0.05）, furthermore, the saturated fatty acids （SFA）, monounsaturated fatty acids （MUFA） and polyunsaturated fatty acids （PUFA） of PLs in both muscles were hydrolysed almost isochronously. FFAs were increased from 0.46 g 100 g-1 lipids to 2.92 g 100 g-1 lipids in BF at the end of salting, which was lower than SM （from 1.29 g 100 g-1 lipids to 9.70 g 100 g-1 lipids）. The activities of acid lipase, neutral lipase and acid phospholipase all remained active in the 90 d. The thiobarbituric acid reactive substances （TBARS） was slowly increased to 1.34 mg kg-1 muscle in BF and to 2.44 mg kg-1 muscle in SM during the salting stage. In conclusion, the controlled salting process prompted the hydrolysis of PLs of IMF notably and increased the lipid oxidation of muscles within some limits.

关键词： Xuanwei ham intramuscular fat lipid oxidation fatty acid composition salting

Proto col Design for Output Consensus of Port-controlled Hamiltonian Multi-agent Systems

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自动化学报 2014年第3期40卷 415-422页

作者： LI Chang-Sheng wang yu-zhen School of Control Science and Engineering Shandong University Jinan 250061 China Department of Information Science and Technology Taishan College Taian 271021 China

这份报纸调查控制港口的 Hamiltonian (PCH ) 多代理人系统的产量一致问题与修理并且切换的拓扑学。第一，一个分布式的组产量一致协议经由塑造方法全球性到达稳定性和组产量一致的能量被设计。第二，一个新分布式的控制协议被使用 PCH... 详细信息

这份报纸调查控制港口的 Hamiltonian (PCH ) 多代理人系统的产量一致问题与修理并且切换的拓扑学。第一，一个分布式的组产量一致协议经由塑造方法全球性到达稳定性和组产量一致的能量被设计。第二，一个新分布式的控制协议被使用 PCH 系统的结构的性质建议。这个协议的优点是它能由构造一种虚拟邻居转变指导的图到未受指导的图。第三，一个控制协议被设计，扩大 LaSalle0s 不变性原则在联合连接的拓扑学条件下面为交换系统发展了让所有代理人当拓扑学正在切换时，到达输出一致。最后，有模拟的一些解说性的例子被提供表明在这份报纸设计的协议的有效性。

关键词：输出端口多Agent系统哈密顿设计受控控制协议多智能体系统拓扑结构