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4D printing of core-shell hydrogel capsules for smart controlled drug release 被引量:6
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作者 Shuo Zu Zhihui Zhang +5 位作者 Qingping Liu Zhenguo Wang Zhengyi Song Yunting Guo Yuanzhu Xin Shuang Zhang 《Bio-Design and Manufacturing》 SCIE EI CAS CSCD 2022年第2期294-304,共11页
Personalized drugs,as well as disease-specific and condition-dependent drug release,have been highly desired in drug delivery systems for effective and safe therapies.Four-dimensional(4 D)printing,as a newly emerging ... Personalized drugs,as well as disease-specific and condition-dependent drug release,have been highly desired in drug delivery systems for effective and safe therapies.Four-dimensional(4 D)printing,as a newly emerging technique to develop drug capsules,displays unique advantages that can autonomously control drug release according to the actual physiological circumstances.Herein,core-shell structured hydrogel capsules were developed using a multimaterial extrusion-based 4 D printing method,which consists of a model drug as the core and UV cross-linked poly(N-isopropylacrylamide)(PNIPAM)hydrogel as the shell.Owing to the lower critical solution temperature(LCST)-induced shrinking/swelling properties,the prepared PNIPAM hydrogel capsules showed temperature-responsive drug release along with the topography changes in the cross-linked PNIPAM network.The in vitro drug release test confirmed that the PNIPAM hydrogel capsules can autonomously control their drug release behaviors according to changes in ambient temperature.Moreover,the increased shell thickness of these capsules causes an obvious reduction in drug release rate,distinctly indicating that the drug release behavior can be well adjusted by setting the shell thickness of the capsules.The proposed 4 D printing strategy pioneers the paradigm of smart drug release by showing great potential in the smart controlled release of drugs and macromolecular active agents. 展开更多
关键词 4d printing Hydrogel capsules controlled release Poly(N-isopropylacrylamide)(PNIPAM) Personalized drugs
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The design and artificial realization of a controller of pulse coupling feedback 被引量:3
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作者 吕翎 郭治安 +2 位作者 栾玲 邹成业 赵鸿雁 《Chinese Physics B》 SCIE EI CAS CSCD 2006年第5期958-962,共5页
In this paper a controller of pulse coupling feedback (PCF) is designed to control chaotic systems. Control principles and the technique to select the feedback coefficients are introduced. This controller is theoret... In this paper a controller of pulse coupling feedback (PCF) is designed to control chaotic systems. Control principles and the technique to select the feedback coefficients are introduced. This controller is theoretically studied with a three dimensional (3D) chaotic system. The artificial simulation results show that the chaotic system can be stabilized to different periodic orbits by using the PCF method, and the number of the periodic orbits are 2^n×3^m p (n and m are integers). Therefore, this control method is effective and practical. 展开更多
关键词 chaos control pulse coupling feedback 3d chaotic system periodic orbit
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Practice of Controlled Temperature Chain (CTC) Technique during a Mass Vaccination Campaign in Côte d’Ivoire 被引量:4
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作者 Damus Paquin Kouassi Lépri Bernadin Nicaise Aka +7 位作者 Bi Vroh Joseph Bénié Soplé Ruth Coulibaly Dodji Blaise Tagodé Daouda Coulibaly Kouadio Félix Koffi Patrick Lydon Anna-Lea Kahn Olivier Ronveaux 《World Journal of Vaccines》 2016年第1期16-22,共7页
Background: MenAfriVac<sup>TM</sup> is the first of the World Health Organization (WHO)’s pre-qualified vaccines to be allowed to mass vaccination campaign at a temperature below or equal to 40°C dur... Background: MenAfriVac<sup>TM</sup> is the first of the World Health Organization (WHO)’s pre-qualified vaccines to be allowed to mass vaccination campaign at a temperature below or equal to 40°C during 4 days. This new vaccination practice has already been used in some African countries. This article described the opinion and use of this new technique by actors on the field, during a mass vaccination campaign in Côte d’Ivoire, in December 2014. Methods: We conducted a crosssectional study on the practice of CTC by actors on the field and their perception on the new practice, during a mass vaccination campaign in 2 of 25 health districts in Côte d’Ivoire, in December 2014. Findings: As results, in Séguéla 98.25% of respondents expressed a favourable opinion of CTC, citing advantages such as vaccine carriers requiring no ice packs (29.2%), financial benefit (12.28%) and lighter vaccine carriers (5.26%). In Bouna, respondents gave the same advantages in, respectively, 34%, 2% and 8% of cases. The peak of the total of vials used for immunization sessions reached 376 vials at day one, then dropped to 235 vials at day three and 220 vials at day six. Discussion: Vaccinators found some benefits related to CTC practice, but on the field, they were cautious in using CTC technique. 展开更多
关键词 MenAfriVac controlled Temperature Chain Vaccine CAMPAIGN Africa Côte d’Ivoire
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MODIFIED AUTOMATIC TUNING OF PI/D CONTROLLERS BASED ON PHASE AND AMPLITUDE MARGIN SPECIFICATIONS
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作者 王亚刚 邵惠鹤 《Journal of Shanghai Jiaotong university(Science)》 EI 1999年第2期17-21,共5页
A new auto tuning procedure for PI/D controller based on phase and amplitude margin specifications was proposed.The procedure applied a modified relay feedback experiment to identifying the process frequency response ... A new auto tuning procedure for PI/D controller based on phase and amplitude margin specifications was proposed.The procedure applied a modified relay feedback experiment to identifying the process frequency response of the point where the Nyquist curve intersects the negative imaginary axis,and the PI/D controller settings can be obtained based on this single point.The auto tuning method has all the merits of the tuning method that Astrom and Hagglund had proposed,and overcomes its problems.The simulation results show that the proposed tuning method has better performance than Astrom Hagglund’s tuning method. 展开更多
关键词 RELAY FEEdBACK PI/d control AUTO tuning frequency response
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Construction Cost Control Strategy of Finished House Based on BIM-5D
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作者 Dongchun Xia Xinyue Zhou 《Journal of World Architecture》 2024年第4期15-20,共6页
Building Information Modeling(BIM)technology can not only achieve project refinement management of the construction process based on a 3D model but also form a BIM-5D model based on the fusion of progress data and cos... Building Information Modeling(BIM)technology can not only achieve project refinement management of the construction process based on a 3D model but also form a BIM-5D model based on the fusion of progress data and cost data to achieve the dynamic control of the whole process of project cost.This paper discusses the application of BIM-5D in the cost control of finished house construction,aiming to provide technical reference for China’s finished house project units,so that they can master how to realize the construction of cost control system based on BIM,the monitoring of the key coefficients of the cost,corrective action,to ensure that the project cost deviation is within the controllable range,and to make an effective guarantee for the economic benefits of the project construction. 展开更多
关键词 BIM-5d Finished house project Cost control system Cost corrective deviation
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Design and Research of Form Controlled Planar Folding Mechanism based on 4D Printing Technology
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作者 Wencai Zhang Zhenghao Ge Duanling Li 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2023年第4期281-293,共13页
The use of non-smart materials in structural components and kinematic pairs allows for flexible assembly in practical applications and is promising for aerospace applications.However,this approach can result in a comp... The use of non-smart materials in structural components and kinematic pairs allows for flexible assembly in practical applications and is promising for aerospace applications.However,this approach can result in a complex structure and excessive kinematic pairs,which limits its potential applications due to the difficulty in controlling and actuating the mechanism.While smart materials have been integrated into certain mechanisms,such integration is generally considered a unique design for specific cases and lacks universality.Therefore,organically combining universal mechanism design with smart materials and 4D printing technology,innovating mechanism types,and systematically exploring the interplay between structural design and morphing control remains an open research area.In this work,a novel form-controlled planar folding mechanism is proposed,which seamlessly integrates the control and actuation system with the structural components and kinematic pairs based on the combination of universal mechanism design with smart materials and 4D printing technology,while achieving self-controlled dimensional ratio adjustment under a predetermined thermal excitation.The design characteristics of the mechanism are analyzed,and the required structural design parameters for the preprogrammed design are derived using a kinematic model.Using smart materials and 4D printing technology,folding programs based on material properties and control programs based on manufacturing parameters are encoded into the form-controlled rod to achieve the preprogrammed design of the mechanism.Finally,two sets of prototype mechanisms are printed to validate the feasibility of the design,the effectiveness of the morphing control programs,and the accuracy of the theoretical analysis.This mechanism not only promotes innovation in mechanism design methods but also shows exceptional promise in satellite calibration devices and spacecraft walking systems. 展开更多
关键词 Form-controlled mechanism Self-folding Smart materials 4d printing Morphing control
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DSP Based Simulator for Speed Control of the Synchronous Reluctance Motor Using Hysteresis Current Controller
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作者 Abdel-Karim Daud Basim Alsayid 《Energy and Power Engineering》 2013年第5期363-371,共9页
This paper presents the field oriented vector control scheme for synchronous reluctance motor (SRM) drives, where current controller followed by hysteresis comparator is used. The test motor has a star-connected wound... This paper presents the field oriented vector control scheme for synchronous reluctance motor (SRM) drives, where current controller followed by hysteresis comparator is used. The test motor has a star-connected wound stator and a segmental rotor of the multiple barrier type with an external incremental encoder to sense rotor position. The magnetic characteristics of this motor are described using 2D finite element method, which is used firstly for rotor design of SRM. The field oriented vector control, that regulates the speed of the SRM, is provided by a quadrature axis current command developed by the speed controller. The simulation includes all realistic components of the system. This enables the calculation of currents and voltages in different parts of the voltage source inverter (VSI) and motor under transient and steady state conditions. Implementation has been done in MATLAB/Simulink. A study of hysteresis control scheme associated with current controllers has been made. Experimental results of the SRM control using TMS320F24X DSP board are presented. The speed of the SRM is successfully controlled in the constant torque region. Experimental results of closed loop speed control of the SRM are given to verify the proposed scheme. 展开更多
关键词 Field Oriented control 2d Finite Element Method SRM HYSTERESIS Current controller dSP MATLAB/SIMULINK
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A comparison of the effect of Vitamin D and Vitamin E supplementations,alone,and in combination,on reducing the intensity and duration of dysmenorrhea in women:A randomized controlled trial
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作者 Tahereh BEHROUZI LAK Nader AGHAKHANI +5 位作者 Davoud VAHABZADEH Samereh EGHTEDAR Rozita CHERAGHI Nazafarin GHASEMZADEH Vahid ALINEJAD Maryam MESGARZADEH 《Journal of Integrative Nursing》 2023年第1期21-26,共6页
Objective:The aim of this study is to compare the effect of Vitamin D and Vitamin E supplementations,alone,and in combination,on reducing the intensity and duration of dysmenorrhea in women who were referred to the Ko... Objective:The aim of this study is to compare the effect of Vitamin D and Vitamin E supplementations,alone,and in combination,on reducing the intensity and duration of dysmenorrhea in women who were referred to the Kowsar gynecological clinics of Shahid Motahari Hospital of Urmia University of Medical Sciences.Materials and Methods:A double-blinded clinical trial was conducted on 112 women with dysmenorrhea who were randomly allocated into the four study groups.Finally,100 women complete the study and received capsules containing a placebo(n=25),1000 IU of Vitamin D(n=25),400 mg of Vitamin E(n=25),and 1000 IU of Vitamin D+400 mg of Vitamin E(n=25)every 24 h for 2 consecutive months at the beginning of the menstrual period.The pain intensity and duration among groups were compared before and after the intervention.Results:The mean menstrual pain duration in all three experimental groups(Vitamin E,Vitamin D,and the combination of them)was lower than the placebo group(all P<0.05),and the mean pain intensity scores in all three experimental groups were significantly lower than the placebo group(all P<0.05).The results(means)for all of the drugs administered at the end of the 2nd month were better than the 1st month(all P<0.01).Conclusions:Vitamin E and Vitamin D,as well as their combination,are recommended as an effective and safe treatment for the management of the complications of dysmenorrhea. 展开更多
关键词 dURATION dYSMENORRHEA INTENSITY randomized controlled trial Vitamin d Vitamin E WOMEN
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State-feedback H_2/H-infinity controller design with D-stability constraints for stochastic systems
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作者 Zhongwei LIN Weihai ZHANG 《控制理论与应用(英文版)》 EI 2007年第3期291-294,共4页
This paper addresses the state-feedback H2/H-infinity controller design that satisfies D-stability constraints for stochastic systems. Firstly, the concept of regional stability for stochastic systems is defined in li... This paper addresses the state-feedback H2/H-infinity controller design that satisfies D-stability constraints for stochastic systems. Firstly, the concept of regional stability for stochastic systems is defined in linear matrix inequality(LMI) regions; Secondly, the characterization about stochastic D-stability is presented. This paper introduces a new technique to solve the regional stability problem for stochastic systems, which is different from the pole placement technique ever used in deterministic systems. Based on this, in the state-feedback case, mixed H2/H-infinity synthesis with D-stability constraints is discussed via LMI optimization. 展开更多
关键词 LMI region d-STABILITY H-infinity control
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Randomized Controlled Trials and Ph.D. Level Training in Educational Research
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作者 Robert Boruch Erling Boe 《Journal of Mathematics and System Science》 2012年第2期94-101,共8页
This invited paper reviews recent initiatives in teaching about randomized field trials at the graduate level in education research. Reports in a book on randomized trials by Mosteller and Boruch are used as a benchma... This invited paper reviews recent initiatives in teaching about randomized field trials at the graduate level in education research. Reports in a book on randomized trials by Mosteller and Boruch are used as a benchmark. The initiatives have been driven heavily by recent governmental emphasis on "evidence based policy" in education, criminology, welfare and other sectors. This policy has been backed, in the US at least, by substantial investments in mounting randomized controlled trials to evaluate curriculum packages and programs in grades K-12, crime prevention programs, welfare, and other work. Accelerated growth in randomized trials has entailed cross discipline pre-doctoral and post-doctoral institutes and graduate education programs aimed at enhancing the quality in trial design, execution, and analysis of results. Specific illustrations of graduate education in this area of statistics are taken mainly from experience at the University of Pennsylvania's Graduate School of Education and selected other institutions. 展开更多
关键词 Randomized controlled trials quantitative methods Ph.d. training in quantitative methods educational research Institute of Education Sciences.
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Non-Fragile Controller Design for 2-D Discrete Uncertain Systems Described by the Roesser Model
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作者 Amit Dhawan 《Journal of Signal and Information Processing》 2012年第2期248-251,共4页
This paper is concerned with the design problem of non-fragile controller for a class of two-dimensional (2-D) discrete uncertain systems described by the Roesser model. The parametric uncertainties are assumed to be ... This paper is concerned with the design problem of non-fragile controller for a class of two-dimensional (2-D) discrete uncertain systems described by the Roesser model. The parametric uncertainties are assumed to be norm-bounded. The aim of this paper is to design a memoryless non-fragile state feedback control law such that the closed-loop system is asymptotically stable for all admissible parameter uncertainties and controller gain variations. A new linear matrix inequality (LMI) based sufficient condition for the existence of such controllers is established. Finally, a numerical example is provided to illustrate the applicability of the proposed method. 展开更多
关键词 2-d dISCRETE Systems NON-FRAGILE control Roesser Model Linear MATRIX INEQUALITY LYAPUNOV Methods
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基于SIMADYN-D的矿井提升机全数字调速系统
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作者 何凤有 袁亚洲 徐志鸥 《煤矿机电》 2006年第2期1-3,6,共4页
本文介绍了基于SIMADYN-D的直流调速系统的硬件组态、软件设计、系统功能及信号流程,实现了矿井提升机的饱和非线性控制和准时间最优控制,使矿井提升机具有良好的静态性能和动态性能。系统经现场运行,达到了稳定、可靠、无故障的良好效果。
关键词 提升机 计算机控制simadyn-d 全数字 调速系统
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基于D-分割法的直流变换器遗传自抗扰控制器设计
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作者 周雪松 王鑫 +3 位作者 马幼捷 王博 赵明 问虎龙 《太阳能学报》 EI CAS CSCD 北大核心 2024年第9期378-385,共8页
针对光伏发电系统中DC-DC变换器由于负载和工作环境条件变化等扰动引起的输出波动问题,提出一种基于D-分割法的直流变换器遗传自抗扰控制器(ADRC)设计方法。该方法适用于设计光伏发电领域中的双向DC-DC变换器,采用D-分割法获得满足闭环... 针对光伏发电系统中DC-DC变换器由于负载和工作环境条件变化等扰动引起的输出波动问题,提出一种基于D-分割法的直流变换器遗传自抗扰控制器(ADRC)设计方法。该方法适用于设计光伏发电领域中的双向DC-DC变换器,采用D-分割法获得满足闭环系统鲁棒稳定的ADRC控制器参数范围;利用具有全局寻优能力的遗传算法,按综合性能指标在该范围内进行参数寻优。实验结果表明,所提基于D-分割法的直流变换器遗传自抗扰控制器设计方法能有效抑制微网母线侧的电压波动和负载突变,提高控制器的鲁棒性,增强光伏发电系统的动态响应性能和抗干扰能力。 展开更多
关键词 光伏发电 dC-dC变换器 遗传算法 自抗扰控制 d-分割法
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Robust H_∞ guaranteed cost satisfactory fault-tolerant control for discrete-time systems with quadratic D stabilizability 被引量:5
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作者 Xiaodong Han Jiangong Liu +2 位作者 Dexiao Xie Dengfeng Zhang Zhiquan Wang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2010年第3期496-502,共7页
The problem of robust H∞ guaranteed cost satisfactory fault-tolerant control with quadratic D stabilizability against actuator failures is investigated for a class of discrete-time systems with value-bounded uncertai... The problem of robust H∞ guaranteed cost satisfactory fault-tolerant control with quadratic D stabilizability against actuator failures is investigated for a class of discrete-time systems with value-bounded uncertainties existing in both the state and control input matrices.Based on a more practical and general model of actuator continuous gain failures,taking the transient property,robust behaviour on H∞ performance and quadratic cost performance requirements into consideration,sufficient conditions for the existence of satisfactory fault-tolerant controller are given and the effective design steps with constraints of multiple performance indices are provided.Meanwhile,the consistency of the regional pole index,H∞ norm-bound constraint and cost performance indices is set up for fault-tolerant control.A simulation example shows the effectiveness of the proposed method. 展开更多
关键词 fault-tolerant control actuator failures consistency theory quadratic d stabilizability.
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基于SIMADYN-D控制器的交-交变频技术在矿井提升机上的应用 被引量:7
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作者 周雨松 孙晓娟 《工矿自动化》 2010年第4期87-89,共3页
针对矿井提升机电控系统的扩容问题,提出了基于西门子SIMADYN-D控制器、结合国产功率柜的矢量控制交-交变频应用方案,分析了SIMADYN-D控制器与国产功率部件的接口问题。实际应用结果表明,该方案降低了交-交变频系统的应用成本,降低了能... 针对矿井提升机电控系统的扩容问题,提出了基于西门子SIMADYN-D控制器、结合国产功率柜的矢量控制交-交变频应用方案,分析了SIMADYN-D控制器与国产功率部件的接口问题。实际应用结果表明,该方案降低了交-交变频系统的应用成本,降低了能耗,扩充了提升机的容量。 展开更多
关键词 矿井 提升机 电控系统 交-交变频 矢量控制 simadyn-d控制器 节能
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A Combining Call Admission Control and Power Control Scheme for D2D Communications Underlaying Cellular Networks 被引量:7
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作者 Xujie Li Wenna Zhang +1 位作者 Honglang Zhang Wenfeng Li 《China Communications》 SCIE CSCD 2016年第10期137-145,共9页
As device-to-device(D2D) communications usually reuses the resource of cellular networks, call admission control(CAC) and power control are crucial problems. However in most power control schemes, total data rates or ... As device-to-device(D2D) communications usually reuses the resource of cellular networks, call admission control(CAC) and power control are crucial problems. However in most power control schemes, total data rates or throughput are regarded as optimization criterion. In this paper, a combining call admission control(CAC) and power control scheme under guaranteeing QoS of every user equipment(UE) is proposed. First, a simple CAC scheme is introduced. Then based on the CAC scheme, a combining call admission control and power control scheme is proposed. Next, the performance of the proposed scheme is evaluated. Finally, maximum DUE pair number and average transmitting power is calculated. Simulation results show that D2 D communications with the proposed combining call admission control and power control scheme can effectively improve the maximum DUE pair number under the premise of meeting necessary QoS. 展开更多
关键词 device-to-device(d2d) call admission control power control cellular networks
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Assessment on the Effects of Hepatitis B Prevention and Control Measures in Western China:A Comparison of Three Population-based Serosurveys 被引量:6
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作者 CHEN Hui LIU Nan +6 位作者 JI Zhao Hua PU Zhong Shu GUO Zhi Wen GAO Jie SHAO Zhong Jun LIU Yi Wen YAN Yong Ping 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2020年第10期735-744,共10页
Objective Despite the remarkable progress in efforts to control disease spread,the nationwide elimination of hepatitis B in China is still hindered by the persistently high rate of hepatitis B virus(HBV)infection in W... Objective Despite the remarkable progress in efforts to control disease spread,the nationwide elimination of hepatitis B in China is still hindered by the persistently high rate of hepatitis B virus(HBV)infection in Western China.This study aimed to evaluate the strategy of hepatitis B prevention and control in Western China and identify potential areas and strategies for improvement.Methods Susceptible population vaccination,health education,professional training of doctors,and other prevention and control measures have been implemented in Wuwei city since 2010.Data were obtained from three representative cross-sectional serosurveys conducted in 2010,2013,and 2015.The serum samples were subjected to enzyme-linked immunosorbent assays to detect the following seromarkers:HBV surface antigen(HBsAg),antibody against hepatitis B surface antigen(anti-HBs),and antibody against hepatitis B core antigen(anti-HBc).Estimates of variance were determined using Taylor series linearization methods.Results The three serosurveys revealed decreases in the prevalence of HBsAg(7.19% in 2010 vs.6.51% in 2013 vs.5.87% in 2015)and anti-HBc positivity(43.89%vs.32.87%vs.28.46%)and an increase in the prevalence of anti-HBs positivity(49.07%vs.53.66%vs.53.72%)over time.From 2010 to 2015,the legally reported incidence of hepatitis B in Wuwei city decreased from 686.53/100,000 to 53.72/100,000.Notably,persistently high HBsAg-positive rates(above 5.40%)were observed among subjects aged 20–69 years old in the three serosurveys;the prevalence of HBsAg was above 1% among children younger than 10 years old.Furthermore,rural subjects had higher rates of HBsAg and anti-HBc positivity than their urban counterparts(6.04%vs.4.83% and 30.26%vs.20.35%,respectively)in 2015 but had a lower rate of anti-HBs positivity(49.68 vs.55.18%).Multivariate regression analysis showed that age,urban and rural areas,and education level were the main factors affecting HBV infection.Conclusion Although vaccine-based prevention and control measures reduced the rate of HBV infection in Wuwei City over time,the hepatitis B infection rate in children younger than 10 years was still higher than the national average level.Therefore,the prevention and control of mother-to-child transmission and the management of the infected should be the focus of future prevention and control work. 展开更多
关键词 Hepatitis B Prevention a n d control measures SEROSURVEY Western China
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Structured Light 3D Vision Based on Laser Scanning Space-encoding and Its Synchro Control 被引量:1
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作者 于晓洋 强锡富 +1 位作者 张健 吴丽莹 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 1997年第2期20-24,共5页
This paper presents the principle and mathematic model for the 3D depth map method based on space encoding images performed by modulating scanning structuredlight according to time sequences,and the synchro control ... This paper presents the principle and mathematic model for the 3D depth map method based on space encoding images performed by modulating scanning structuredlight according to time sequences,and the synchro control among the camera,laser diode modulation and scanning polyhedron. 展开更多
关键词 d VISION STRUCTUREd LIGHT space encoding LASER SCANNING SYNCHRO control
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A Numerical-analytic Method for Quickly Predicting Springback of Numerical Control Bending of Thin-walled Tube 被引量:3
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作者 Mei ZHAN He YANG Liang HUANG 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2006年第5期713-720,共8页
Springback is one of important factors influencing the forming quality of numerical control (NC) bending of thin-walled tube. In this paper, a numerical-analytic method for springback angle prediction of the process... Springback is one of important factors influencing the forming quality of numerical control (NC) bending of thin-walled tube. In this paper, a numerical-analytic method for springback angle prediction of the process was put forward. The method is based on springback angle model derived using analytic method and simulation results from three-dimensional (3D) rigid-plastic finite element method (FEM). The method is validated through comparison with experimental results. The features of the method are as follows: (1) The method is high in efficiency because it combines advantages of rigid-plastic FEM and analytic method. (2) The method is satisfactory in accuracy, since the field variables used in the model is resulting from 3D rigid-plastic FEM solution, and the effects both of axial force and strain neutral axis shift have been included. (3) Research on multi-factor effects can be carried out using the method due to its advantage inheriting from rigid-plastic FEM. The method described here is also of general significance to other bending processes. 展开更多
关键词 Thin-walled tube Numerical control bending SPRINGBACK Numerical-analytic method 3d rigid-plastic FEM
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Feedback iterative learning control for time-delay systems based on 2D analysis approach 被引量:3
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作者 Deyuan MENG Yingmin JIA +1 位作者 Junping DU Shiying YUAN 《控制理论与应用(英文版)》 EI 2010年第4期457-463,共7页
This paper deals with the iterative learning control (ILC) design for multiple-input multiple-output (MIMO),time-delay systems (TDS).Two feedback ILC schemes are considered using the so-called two-dimensional ... This paper deals with the iterative learning control (ILC) design for multiple-input multiple-output (MIMO),time-delay systems (TDS).Two feedback ILC schemes are considered using the so-called two-dimensional (2D) analysis approach.It shows that continuous-discrete 2D Roesser systems can be developed to describe the entire learning dynamics of both ILC schemes,based on which necessary and sufficient conditions for their stability can be provided.A numerical example is included to validate the theoretical analysis. 展开更多
关键词 Iterative learning control Time-delay systems 2d analysis approach
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