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The Prevalence of Hepatitis C Virus Infection in Oral Lichen Planus in an Ethnic Chinese Cohort of 232 Patients

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International Journal of Oral Science 2010年第2期2卷 90-97页

作者： Yu Zhou Lu Jiang Jie Liu xin zeng Qian-ming chen State Key Laboratory of Oral Diseases West China College of Stomatology Sichuan University Chengdu China Section of Oral Biology College of Dentistry the Ohio State University Columbus USA

Aim Oral lichen planush （OLP） is a chronic inflammatory disease, and has been reported to have a correlation with hepatitis Cvirus （HCV） infection in some regional investigations. In this study, we investigated the prevalence of HCV in patients with oral lichen planus in an ethnic Chinese cohort. Methodology The antibody of HCV infection was detected by using enzymelinked immunosorbent assay. Moreover, the clinical characteristics of whole the cohort have also been studied, such as the gender, age, clinical type, habits and social factors. Results Of all 232 patients, the antibody of HCV infection was detected positive in 4 patients （1.72%） using enzyme-linked immunosorbent assay. It was lower than that in control group of 2.5%, but not significant （P=0.309）. The positive rate of HCV antibody in the erosive type ones （4.2%） was higher than that in the reticular type ones （1.0%）, but this difference was proved to be not significant （P=0.389）. The clinical characteristics of whole cohort, such as the gender, age, clinical type, habits and social factors, showed the outcome obtained in the present study were similar to thao of our previous study. Conclusion HCV may play no etiological role in oral lichen planus in ethnic Chinese OLP patients.

关键词： hepatitis Cvirus oral lichen planus epidemiology Chinese cohort

Tracking with nonlinear measurement model by coordinate rotation transformation

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Science China(Technological Sciences) 2014年第12期57卷 2396-2406页

作者： zeng Tao LI Chun Xia LIU Quan Hua chen xin Liang School of Information and Electronics Beijing Institute of Technology

A new filtering method is proposed to accurately estimate target state via decreasing the nonlinearity between radar polar measurements(or spherical measurements in three-dimensional(3D) radar) and target position in Cartesian coordinate. The degree of linearity is quantified here by utilizing correlation coefficient and Taylor series expansion. With the proposed method, the original measurements are converted from polar or spherical coordinate to a carefully chosen Cartesian coordinate system that is obtained by coordinate rotation transformation to maximize the linearity degree of the conversion function from polar/spherical to Cartesian coordinate. Then the target state is filtered along each axis of the chosen Cartesian coordinate. This method is compared with extended Kalman filter(EKF), Converted Measurement Kalman filter(CMKF), unscented Kalman filter(UKF) as well as Decoupled Converted Measurement Kalman filter(DECMKF). This new method provides highly accurate position and velocity with consistent estimation.

关键词： target tracking Kalman filtering nonlinear filtering decoupled nonlinearity

Evaluating the hydrological effects of the Three Gorges Reservoir based on a large-scale coupled hydrological-hydrodynamic-dam operation model

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Journal of Geographical Sciences 2023年第5期33卷 999-1022页

作者： zeng Sidong LIU xin- XIA Jun DU Hong chen Minghao HUANG Renyong Chongqing Institute of Green and Intelligent Technology CASChongqing400714China Chongqing School University of Chinese Academy of SciencesChongqing400714China State Key Laboratory of Water Resources and Hydropower Engineering Science Wuhan UniversityWuhan430072China College of Resources and Environmental Science South-Central Minzu UniversityWuhan430074China Yangtze River Scientific Research Institute Wuhan430010China

Understanding the hydrological effects of the Three Gorges Dam operation in the entire reservoir area is significant to achieving optimal dam regulation. In this paper, a large-scale coupled hydrological-hydrodynamic-dam operation model is developed to comprehensively evaluate the hydrological effects of the river-type Three Gorges Reservoir. The results show that the coupled model is effective for hydrological, hydrodynamic regime and hydropower simulations in the reservoir area. Dam operation could have a notable positive effect on flood control and could reduce the maximum daily flood peak by up to 26.2%. It also contributes a large amount of hydropower, approximately 94.27 TWh/year, and a water supply increase for the downstream area of up to 22% during the dry season. In the flood season, the water level at Cuntan would increase under the condition that the water level of the dam is higher than approximately 158 m due to dam operation. In the dry season, attention should be paid to the low flow velocity near the dam in the reservoir area.

关键词： hydrological effects Three Gorges Reservoir coupled model flood control

Deformation mechanism of commercially pure titanium under biaxial loading at ambient and elevated temperatures

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Journal of Materials Science & Technology 2022年第31期126卷 237-251页

作者： Yuanjie Fu Yao cheng Yun Cui Yunchang xin Yuyao zeng Xiao Liu Gang chen School of Chemical Engineering and Technology Tianjin UniversityTianjin 300350China Key Laboratory for Light-weight Materials Nanjing Tech UniversityNanjingJiangsu 210009China School of Chemical Engineering and Technology Tianjin Ren’ai CollegeTianjin 301636China Tianjin Key Laboratory of Chemical Process Safety and Equipment Technology Tianjin 300350China Zhejiang Institute of Tianjin University NingboZhejiang 315201China Nuclear Power Institute of China ChengduSichuan 610015China

Commercially pure(CP)titanium is thermally processed and subjected to biaxial ***,the evolution of the microstructural deformation mechanisms under such circumstances is not adequately *** this study,the mechanical responses and microstructural deformation mechanisms of TA2 CP titanium sheets under equi-biaxial loading at room temperature(RT),300℃,and 400℃were *** activated slip and twinning systems were investigated by transmission electron microscopy(TEM)after polished cruciform specimens were biaxially tensile-tested at RT and elevated *** results show that{11¯22}contraction twinning and{10¯12}extension twinning are the main deforma-tion mechanisms of RT biaxial deformation,while dislocation glide is predominant in biaxial deformation at 300℃and 400℃.This difference yields varied work-hardening behaviors at RT and elevated *** biaxial deformation at 400℃,the main slip trace type is multiple *** interaction of different slip systems in multiple slip created shear deformation concentration areas and further induced ***,in biaxial deformation at 300℃,the amounts of simplex and multiple slip were significantly reduced compared to those at 400℃because the lower temperature increased the critical resolved shear stress and insufficient activated slip systems were available for grain ***-fore,several stress-concentration areas were generated with the activation of cross-slip.

关键词： CP titanium Biaxial tensile tests High temperature Dislocation glide TEM

Multi-Objective Cooperative Salvo Attack Against Group Target

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Journal of Systems Science & Complexity 2018年第1期31卷 244-261页

作者： zeng Jie DOU Lihua xin Bin School of Automation State Key Laboratory of Intelligent Control and Decision of Complex SystemsBeijing Advanced Innovation Center for Intelligent Robots and Systems Beijing Institute of Technology

This paper proposes a solution for the problem of cooperative salvo attack of multiple cruise missiles against targets in a group. Synchronization of the arrival time of missiles to hit their common target, minimizing the time consumption of attack and maximizing the expected damage to group targets are taken into consideration simultaneously. These operational objectives result in a hierarchical mixed-variable optimization problem which includes two types of subproblems, namely the multi-objective missile-target assignment（MOMTA） problem at the upper level and the time-optimal coordinated path planning（TOCPP） problems at the lower level. In order to solve the challenging problem, a recently proposed coordinated path planning method is employed to solve the TOCPP problems to achieve the soonest salvo attack against each target. With the aim of finding a more competent solver for MOMTA, three state-of-the-art multi-objective optimization methods（MOMs）,namely NSGA-II, MOEA/D and DMOEA-εC, are adopted. Finally, a typical example is used to demonstrate the advantage of the proposed method. A simple rule-based method is also employed for comparison. Comparative results show that DMOEA-εC is the best choice among the three MOMs for solving the MOMTA problem. The combination of DMOEA-εC for MOMTA and the coordinated path planning method for TOCPP can generate obviously better salvo attack schemes than the rule-based method.

关键词： Coordinated path planning missile-target assignment multi-missile salvo attack multiobjective optimization

Advanced regeneration and fixed-bed study of ammonium and potassium removal from anaerobic digested wastewater by natural zeolite

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Journal of Environmental Sciences 2013年第5期25卷 954-961页

作者： Xuejun Guo Larry zeng xin Jin State Key Laboratory of Water Environment Simulation School of EnvironmentBeijing Normal University Environmental Technologies Alberta Research Council Inc.VegrevilleAlberta T9C 1T4Canada

Highly efficient regeneration of natural zeolite was developed in conjunction with the removal of high concentrations of ammonia and potassium from the reverse osmosis effluent of anaerobic-digested wastewater by fixed-bed ion *** elution and uptake behavior of ammonium and potassium in the fixed bed were *** batch desorption tests and on-column regeneration were conducted to develop an optimum regeneration condition compatible with the wastewater *** effectiveness of ammonium elution increased with increasing alkaline *** increase of salt dose significantly enhanced the ammonium maximum in the elution *** ammonium elution was achieved in 6 bed volumes（BV） when the alkaline and salt concentrations were respectively 0.1 mol/L and 18.6 g/L at a flow rate of 2.5-3.0 BV/*** to the higher affinity of potassium with natural clinoptilolite,complete potassium elution was not achieved in all cases.

关键词： regeneration removal ammonium potassium natural zeolite

A joint mid-course and terminal course cooperative guidance law for multi-missile salvo attack

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Chinese Journal of Aeronautics 2018年第6期31卷 1311-1326页

作者： Jie zeng Lihua DOU Bin xin School of Automation Beijing Institute of Technology Beijing 100081 China State Key Laboratory of Intelligent Control and Decision of-Complex Systems Beijing 100081 China

Salvo attacking a surface target by multiple missiles is an effective tactic to enhance the lethality and penetrate the defense system. However, existing cooperative guidance laws in the midcourse or terminal course are not suitable for long-and medium-range missiles or stand-off attacking. Because the initial conditions of cooperative terminal guidance that are generally generated from the mid-course flight may not lead to a successful cooperative terminal guidance without proper mid-course flight adjustment. Meanwhile, cooperative guidance in the mid-course cannot solely guarantee the accuracy of a simultaneous arrival of multiple missiles. Therefore, a joint mid-course and terminal course cooperative guidance law is developed. By building a distinct leader-follower framework, this paper proposes an efficient coordinated Dubins path planning method to synchronize the arrival time of all engaged missiles in the mid-course flight. The planned flight can generate proper initial conditions for cooperative terminal guidance, and also benefit an earliest simultaneous arrival. In the terminal course, an existing cooperative proportional navigation guidance law guides all the engaged missiles to arrive at a target accurately and *** integrated guidance law for an intuitive application is summarized. Simulations demonstrate that the proposed method can generate fast and accurate salvo attack.

关键词： Cooperative systems Dubins path Mid-course flight Missile guidance Salvo attack

Design and evaluation of control strategies in urban drainage systems in Kunming city

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Frontiers of Environmental Science & Engineering 2017年第4期11卷 105-112页

作者： xin Dong Senchen Huang Siyu zeng School of Environment Tsinghua University Beijing 100084 China

Real time control （RTC） of urban drainage systems （UDSs） is an important measure to reduce combined sewer overflow （CSO） and urban flooding, helping achieve the aims of ＂Sponge City＇. Application of RTC requires three main steps： strategy design, simulation-based evaluation and field test. But many of published RTC studies are system-specific, lacking discussions on how to design a strategy step by step. In addition, the existing studies are prone to use hydrologic model to evaluated strategics, but a more precise and dynamic insight into strategy performance is needed. To fill these knowledge gaps, based on a case UDS in Kunming city, a studio on RTC strategy design and Management Model （SWMM） - uncier four typical rainfall events characterized by different return periods （1-year or 0.5 year） and different spatial distributions （uniform or uneven）. The equal filling strategy outperformss other two strategies and it can achieve 10% more CSO reduction and 5% more flooding reduction relative to the no-tank case.

关键词： Urban drainage system Real time control Static strategy Constant strategy Equal filling strategy

Comprehensive analysis of the influence of structural and dynamic parameters on the accuracy of nano-precision positioning stages

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Frontiers of Mechanical Engineering 2019年第3期14卷 255-272页

作者： chengyuan LIANG Fang YUAN Xuedong chen Wei JIANG Lizhan zeng xin LUO State Key Laboratory of Digital Manufacturing Equipment and Technology Huazhong University of Science and Technology Wuhan 430074 China

Nano-precision positioning stages are characterized by rigid-flexible coupling systems. The complex dynamic characteristics of mechanical structure of a stage, which are determined by structural and dynamic parameters, exert a serious influence on the accuracy of its motion and measurement. Systematic evaluation of such influence is essential for the design and improvement of stages. A systematic approach to modeling the dynamic accuracy of a nano-precision positioning stage is developed in this work by integrating a multi-rigid-body dynamic model of the mechanical system and measurement system models. The influence of structural and dynamic parameters, including aerostatic bearing configurations, motion plane errors, foundation vibrations, and positions of the acting points of driving forces, on dynamic accuracy is investigated by adopting the H-type configured stage as an example. The approach is programmed and integrated into a software framework that supports the dynamic design of nano-precision positioning stages. The software framework is then applied to the design of a nano-precision positioning stage used in a packaging lithography machine.

关键词： nano-precision positioning stage analysis and design structural and dynamic parameters dynamic accuracy systematic modeling