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Effect of Media on the Electric Field of a Rhombic Nanostructure Array

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Chinese Physics Letters 2010年第6期27卷 217-220页

作者： ZHU shao-li ZHOU Wei Precision Engineering and Nanotechnology Centre School of Mechanical and Aerospace Engineering Nanyang Technological University 50 Nanyang Avenue Singapore 639798

Electric field distribution is an important parameter for nanostructure arrays in nanobiosensing appfications. It can influence the sensitivity and the resolution of nanobiosensors. We focus on the effect of media on the electric field distribution of a rhombic silver nanostructure array. The finite-difference time-domain algorithm- based numerical calculation method is used to monitor the electric field distribution of the silver nanostructures when the refractive index of the medium around the nanostructure array is changed. The calculated results show that tuning the refractive index of the medium around silver can have a considerable influence on the electric field distribution in the reflection and transmission directions. This effect can be used to increase the extinction efficiency and to improve the resolution of the spectra for nanobiosensing.

关键词： ELECTRIC fields NANOSTRUCTURES RHOMBIC antennas BIOSENSORS SENSITIVITY analysis FINITE differences TIME-domain analysis NUMERICAL calculations

Sealing Performance and Optimization of a Subsea Pipeline Mechanical Connector

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Chinese Journal of Mechanical Engineering 2018年第1期31卷 142-155页

作者： li-Quan Wang Zong-liang Wei shao-Ming Yao Yu Guan shao-Kai li College of Mechanical and Electrical Engineering Harbin Engineering University Advanced Manufacturing Research Centre with Boeing The University of Sheffield

Researchers seldom study the optimum design of a mechanical connector for subsea oil-gas pipeline based upon the sealing performance. An optimal design method of a novel subsea pipeline mechanical connector is presented. By analyzing the static metal sealing mechanism, the critical condition of the sealing performance is established for this connector and the formulation method of the contact pressure on the sealing surface is created. By the method the minimum mean contact pressure of the 8.625 inch connector is calculated as 361 MPa, which is the constraint condition in the optimum design of *** finite element model is created in ANSYS Parametric Design Language(APDL) and the structure is optimized by the zero-order method, with variance of contact pressure as the objective function, and mean contact pressures and plastic strains as constraint variables. The optimization shows that variances of contact pressure on two sealing surfaces decrease by 72.41% and 89.33%, respectively, and mean contact pressures increase by 31.18% and 52.84%, respectively. The comparison of the optimal connectors and non-optimal connectors in the water pressure experiments and bending experiments shows that the sealing ability of optimized connectors is much higher than the rated pressure of 4.5 MPa, and the optimal connectors don’t leak under the bending moment of 52.2 kN·*** research provides the formulation to solve contact pressure on the sealing surface and a structure optimization method to design the connectors with various dimensions.

关键词： Mechanical connector Sealing mechanism Sealing performance Critical condition Minimum mean contact pressure Variance

Pancharatnam–Berry metasurface for terahertz wave radar cross section reduction

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Chinese Physics B 2019年第9期28卷 220-226页

作者： shao-He li Jiu-Sheng li Center for THz Research China Jiliang University

The digital coding metasurfaces need several kinds of meta-particle structures to obtain corresponding electromagnetic wave responses and require time-consuming *** this paper, we present train-symbol-shaped meta-particles with various orientations utilizing Pancharatnam-Berry(PB) phase to achieve 1-, 2-, and 3-bit digital coding *** wave scattering patterns of the coding metasurfaces with regular and random sequences are given and *** have strongly suppressed backward scattering with approximately-13.5 dB radar cross section(RCS) reduction in a wide band range from 0.85 THz to 1.6 *** proposed digital coding metasurfaces provide a simple way and new opportunities for manipulating terahertz wave scattering with polarization independence.

关键词： terahertz metasurface terahertz optics terahertz polarization

Crowdsourcing aggregation with deep Bayesian learning

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Science China(Information Sciences) 2021年第3期64卷 46-56页

作者： shao-Yuan li Sheng-Jun HUANG Songcan CHEN College of Computer Science and Technology College of Artificial IntelligenceNanjing University of Aeronautics and Astronautics State Key Laboratory for Novel Software Technology Nanjing University

In this study, we consider a crowdsourcing classification problem in which labeling information from crowds is aggregated to infer latent true labels. We propose a fully Bayesian deep generative crowdsourcing model(Bayes DGC), which combines the strength of deep neural networks(DNNs) on automatic representation learning and the interpretable probabilistic structure encoding of probabilistic graphical models. The model comprises a DNN classifier as a prior for the true labels and a probabilistic model for the annotation generation process. The DNN classifier and annotation generation process share the latent true label variables. To address the inference challenge, we developed a natural-gradient stochastic variational inference, which combines variational message passing for conjugate parameters and stochastic gradient descent for DNN and learns the distribution of latent true labels and workers’ confusion matrix via end-to-end training. We illustrated the effectiveness of the proposed model using empirical results on 22 real-world datasets.

关键词： crowdsourcing classification fully Bayesian deep generative models natural gradient stochastic variational inference

Ranking effects of candidate drugs on biological process by integrating network analysis and Gene Ontology

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Chinese Science Bulletin 2010年第26期55卷 2974-2980页

作者： li liSha ZHANG NingBo li shao MOE Key Laboratory of Bioinformatics Division TNLIST/Department of Automation Tsinghua University Beijing 100084 China

There are high preclinical attrition rates in current drug discovery. The efficient assessment approach in the high throughout candidate drugs screening still needs great improvement. We propose two hypotheses. First, both drug action process and biological process can be converted to a common space of gene or gene product profiling. Second, the strength of drug action on biological process can be realized in the context of biological network. Based on the above hypotheses, we establish an algorithm termed Network-based Assessment for Drug Action (NADA) to assess the action strength of candidate drugs on certain biological processes. Then NADA is used to prioritize the effects of six compounds from traditional Chinese medicine on endothelial cell migration, a simple process defined by Gene Ontology, in the biological network specific for a given pathological process, angiogenesis. The computational results are subsequently tested by the experiment on the migration of Human Umbilical Vein Endothelial Cells in vitro. The experimental ranks for six compounds generally agree with the predicted output of NADA. NADA also outperforms the DAVID and meet/min methods in terms of the experimental orders, suggesting that the network topological features may have a key role in catching the mechanistic relationship between drug action and biological process. Hopefully, the progress of network biology approaches for deciphering complex diseases will further expedite the preclinical screening and accelerate the development of treatment modalities.

关键词：基因本体论药物作用生物过程网络分析过程集成人脐静脉内皮细胞细胞迁移产物分析

Model Predictive Control for Vapor Compression Cycle of Refrigeration Process

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International Journal of Automation and computing 2018年第6期15卷 707-715页

作者： Xiao-Hong Yin shao-Yuan li Department of Automation Shanghai Jiao Tong University and Key Laboratory of System Control and Information Processing Ministry of Education of China

A model predictive controller based on a novel structure selection criterion for the vapor compression cycle （VCC） of refrigeration process is proposed in this paper. Firstly, those system variables are analyzed which exert significant influences on the system performance. Then the structure selection criterion, a trade-off between computation complexity and model performance, is applied to different model structures, and the results are utilized to determine the optimized model structure for controller design. The controller based on multivariable model predictive control （MPC） strategy is designed, and the optimization problem for the reduced order models is formulated as a constrained minimization problem. The effectiveness of the proposed MPC controller is verified on the experimental rig.

关键词： Vapor compression refrigeration cycle model structure structure selection criterion model reduction model predictive control.

Speciation of heavy metals in airborne particles,road dusts,and soils along expressways in China

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Chinese Journal Of Geochemistry 2013年第4期32卷 420-429页

作者： shao li XIAO Huayun WU Daishe Environmental and Chemical Engineering College Nanchang University State Key Laboratory of Environment Geochemistry Institute of GeochemistryChinese Academy of Sciences

This study analyzed the concentrations and chemical forms of Zn,Cu,Pb,Sb,Cd and Mn in airborne particles,road dusts and soils collected along three expressways in Jiangxi Province,China,with different traffic densities,and identified the levels and sources of heavy metal *** concentrations of Zn,Cu,Pb,Sb,and Cd except Mn in airborne particles,road dusts and soils were all in direct proportion to traffic *** concentrations were low compared with other *** instance,the concentrations of Zn,Cu,Pb,Sb,Mn and Cd were 6.6,0.7,2.2,0.1,0.1 and 0.1μg·m-3in PM10along the Changjiu Expressway,792.8,241.4,248.3,9.6,340.5and 8.0 mg·kg-1in road dusts,and 201.1,143.2,59.5,9.5,338.9 and 2.3 mg·kg-1in soils,respectively,but in the case of the ratio of concentration to the environmental background value,most serious contamination was caused by *** sources of the heavy metals were judged by comparisons of the chemical forms of the heavy metals in different environmental *** and Mn in airborne particles were both derived from traffic;Pb in road dusts and soils resulted mainly from the use of leaded gasoline in the past;and Mn in road dusts and soils was derived from parent ***,Cu,Sb and Cd in airborne particles,road dusts and soils were derived primarily from traffic,and differences in chemical forms of the heavy metals in different media were due to the interaction between heavy metals in airborne particles and organic matter and other surfaces in road dusts and *** also discussed the change of chemical forms of heavy metals in particles of different sizes and under different weather *** of heavy metals in airborne particles was much higher than that in road dusts and soils,especially Pb(0.676 in airborne particles,0.159 in road dusts and 0.095 in soils).

关键词：大气颗粒物重金属形态中国土壤高速公路空气道路粉尘生物有效性

Homoclinic and Heteroclinic Flows in Global Attractor for Davey-stewartson Ⅱ Equation

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Acta Mathematicae Applicatae Sinica 2008年第4期24卷 599-612页

作者： Zheng-de Dai shao-lin li School of Mathematics and Statistics Yunnan University Kunming 650091 China Department of Information and Computing Science Guangxi Institute of Technology Liuzhou 545006 China Department of Mathematics Honghe College Mengzi 661100 China

By the variable transformation and generalized Hirota method, exact homoclinic and heteroclinic solutions for Davey-Stewartson II （DSII） equation are obtained. For perturbed DSII equation, the existence of a global attractor is proved. The persistence of homoclinic and heteroclinic flows is investigated, and the special homoclinic and heteroclinic structure in attractors is shown.

关键词： Persistence Homoclinic And Heteroclinic Flows Attractor Davey-Stewarson equation

Predictive Zone Control of Pressure Management for Water Supply Network Systems

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International Journal of Automation and computing 2016年第6期13卷 607-614页

作者： Dong-Ming liu shao-Yuan li Department of Automation Shanghai Jiao Tong University Shanghai 200240 China Key Laboratory of System Control and Information Processing Ministry of Education Shanghai 200240 China Changzhou Institute of light Industry Technology Jiangsu 213164 China

In this paper we address the problem of pressure management in water supply system （WSS） network. The model-based predictive control （MPC） strategies have some important features to deal with WSS. By hydraulic analysis of WSS, the predictive model is derived from the dynamic model and static model of WSS. Through WSS, the consumers＇ demands are required to be met at all times according to some operational constraints that must be satisfied. The constraints of flow through actuators, the water level of reservoirs and the consumer areas＇ pressure demand are determined by a specific system. In this work, we develop a constrained MPC controller that considers the zone control of the pressure outputs and incorporates steady state economic targets in the control cost function. The designed management strategies are applied to a case study and simulation results, covering different aspects, are provided. The output nodal pressure can be controlled in the desired zone by optimal scheduling the actuators of the WSS. If the variation range of reservoir＇s water level is broader, the rate of flow through the actuators is gentle, and vice versa.

关键词： Water supply system (WSS) network mathematical modelling zone control pressure control model predictive control(MPC).