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Traditional Chinese Medicine treatment with syndrome differentiation for patients with severe community-acquired pneumonia:a multicenter,randomized,placebo-controlled trial
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作者 LI Jiansheng WANG Haifeng +4 位作者 ZHANG Kang XIE Kai LI Suyun ZHANG Chenxi ZHANG Yaqing 《Journal of Traditional Chinese Medicine》 2025年第6期1376-1384,共9页
OBJECTIVE:To assess the effect of Traditional Chinese Medicine(TCM)treatment with syndrome differentiation in patients with severe community-acquired pneumonia(CAP).METHODS:A multicenter,randomized,placebocontrolled t... OBJECTIVE:To assess the effect of Traditional Chinese Medicine(TCM)treatment with syndrome differentiation in patients with severe community-acquired pneumonia(CAP).METHODS:A multicenter,randomized,placebocontrolled trial was conducted.Adult patients with severe CAP were randomly allocated to receive conventional medicine treatment(conventional group)or conventional medicine combine with TCM treatment with syndrome differentiation(combination group)underwent a 28-d treatment time.The primary endpoint was treatment failure.Secondary outcomes included time to clinical stability,28-d mortality,90-d mortality,length of hospital stay.RESULTS:A total of 183 patients were included in the intention-to-treat(ITT)population,with 91 allocated to the combination group and 92 to the conventional group.Patients with treatment failure in the combination group(18/91,19.8%)were lower compared with the conventional group(34/92,37.0%).Time to clinical stability was shorter in the combination group(11.8 d)than in the conventional group[17.8 d;HR=2.08,95%CI(1.38,3.14);P=0.001].The 28-d mortality was lower in the combination group(17.6%)than in the conventional group(31.5%).There was no difference in the length of hospital stay between the two groups(P=0.901).Adverse events were evenly distributed between the combination and conventional groups(P=0.837).CONCLUSION:Among patients with severe CAP,TCM treatment with syndrome differentiation reduced treatment failure,time to clinical stability,and the 28-d mortality and the 90-d mortality among patients admitted to the ward,without an increase in complications. 展开更多
关键词 community-acquired pneumonia treatment failure randomized controlled trial medicine Chinese traditional treatment with syndrome differentiation
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ON REGIONAL DIFFERENTIATION OF RIVER WATER ENVIRONMENT CAPACITY AND STRATEGIES TO CONTROL WATER ENVIRONMENT POLLUTION IN CHINA 被引量:4
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作者 王华东 王淑华 +1 位作者 鲍全盛 祁忠 《Chinese Geographical Science》 SCIE CSCD 1995年第2期116-124,共9页
China has large population and wide territory, the natural conditions of different regions are complicated. water resources are distributed unbalanced.economic developing states are unequal. For these reasons the vari... China has large population and wide territory, the natural conditions of different regions are complicated. water resources are distributed unbalanced.economic developing states are unequal. For these reasons the variation of concerned water environment capacity has obvious character of regional differentiation. In this paper, from the economic development point of view, the regular pattern of regional differentiation of China's water environment capacity resources is analyzed. the concept of contradictory degree between water environment capacity and economic development is introduced, based on them, rivers in China are divided into three regions, and corresponding strategies to control water pollution are advanced. The aims are to use river water environment capacity resources effectively. to control pollution and to improve environmental quality. 展开更多
关键词 WATER ENVIRONMENT capacity. REGIONAL differentiation. pollutioncontrol total quantity control
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Randomized controlled multicenter clinical trial for integrated treatment of community-acquired pneumonia based on Traditional Chinese Medicine syndrome differentiation 被引量:14
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作者 Jiansheng Li Xueqing Yu +8 位作者 Suyun Li Haifeng Wang Yunping Bai Minghang Wang Zikai Sun Wei Zhang Zhaoshan Zhou Xianhua Jia Qingwei Zhou 《Journal of Traditional Chinese Medicine》 SCIE CAS CSCD 2012年第4期554-560,共7页
OBJECTIVE:To evaluate the efficacy and safety of treatment based on syndrome differentiation ofTraditional Chinese Medicine(TCM) for community-acquired pneumonia(CAP).METHODS:A total of 240 CAP patients were randomly ... OBJECTIVE:To evaluate the efficacy and safety of treatment based on syndrome differentiation ofTraditional Chinese Medicine(TCM) for community-acquired pneumonia(CAP).METHODS:A total of 240 CAP patients were randomly divided into the following two groups:thecontrol group was treated by anti-infection plus conventional medicine treatment;and the trial group was treated by TCM plus the above-mentioned treatment given to the controls.The course of treatment was 14 days,and the patients were followed up for 7 days.RESULTS:Of the 240 patients,235 accomplished the whole process of treatment.The five patients who withdrew from the study were brought into an intent-to-treat analysis.The therapeutic effects of the trial group were superior to those of the control group(P<0.01).The trial group took less time to become clinically stable,with a higher score in the quality of life(P<0.01).There were no significant differences in mortality rate(P>0.05),white blood cell count(P>0.05),bacterial clearance rate(P>0.05),and adverse reactions between the two integrated groups.CONCLUSION:Treatment based on TCM syndrome differentiation for CAP has the advantages of resulting in less time to achieve a stable clinical condition,improvement of clinical symptoms and quality of life,and is comparatively safe. 展开更多
关键词 Community-acquired infections Pneu-monia Syndrome differentiation treatment Ran-domized controlled trials
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Integrated traditional and Western medicine for treatment of depression based on syndrome differentiation:a meta-analysis of randomized controlled trials based on the Hamilton depression scale 被引量:13
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作者 寇美静 陈家旭 《Journal of Traditional Chinese Medicine》 SCIE CAS CSCD 2012年第1期1-5,共5页
OBJECTIVE:To systematically review the benefits of integrated traditional and Western medicine therapies based on the Hamilton depression scale(HAMD) following syndrome differentiation of depression.METHODS:We searche... OBJECTIVE:To systematically review the benefits of integrated traditional and Western medicine therapies based on the Hamilton depression scale(HAMD) following syndrome differentiation of depression.METHODS:We searched six English and Chinese electronic databases for randomized clinical trials(RCTs) on integrated traditional and Western medicine for treatment of depression.Two authors extracted data and independently assessed the trial quality.RevMan 5 software was used for data analyses with an effect estimate presented as weighted mean difference(WMD) with a 95% confidence interval(CI).RESULTS:Seven RCTs with 576 participants were identified for this review.All trials were eligible for the meta-analysis and were evaluated as unclear or having a risk of bias.Meta-analysis showed,compared with Western medicine alone,integrated traditional and Western medicine based on syndrome differentiation could improve the effect of treatment represented by the HAMD [WMD=-2.39,CI(-2.96,-1.83),Z=8.29,P<0.00001].There were no reported serious adverse effects that were related to integrated traditional and Western medicine based therapies in these trials.CONCLUSIONS:Integrated traditional and Western medicine based therapies for the syndrome differentiation of depression significantly improved the HAMD,illustrating that combining therapies from integrated traditional and Western medicine for treatment of depression is better than Western medicine alone.However,further large,rigorously designed trials are warranted due to the insufficient methodological rigor seen in the trials included in this study. 展开更多
关键词 Syndrome differentiation DEPRESSION Integrated traditional and western medicine META-ANALYSIS Randomized controlled trials
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Proportion Integration Differentiation(PID)Control Strategy of Belt Sander Based on Fuzzy Algorithm 被引量:2
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作者 陈坤 张亚伟 +1 位作者 张振 桂志伟 《Journal of Donghua University(English Edition)》 CAS 2023年第2期177-184,共8页
Aiming at solving the problems of response lag and lack of precision and stability in constant grinding force control of industrial robot belts,a constant force control strategy combining fuzzy control and proportion ... Aiming at solving the problems of response lag and lack of precision and stability in constant grinding force control of industrial robot belts,a constant force control strategy combining fuzzy control and proportion integration differentiation(PID)was proposed by analyzing the signal transmission process and the dynamic characteristics of the grinding mechanism.The simulation results showed that compared with the classical PID control strategy,the system adjustment time was shortened by 98.7%,the overshoot was reduced by 5.1%,and the control error was 0.2%-0.5%when the system was stabilized.The optimized fuzzy control system had fast adjustment speeds,precise force control and stability.The experimental analysis of the surface morphology of the machined blade was carried out by the industrial robot abrasive grinding mechanism,and the correctness of the theoretical analysis and the effectiveness of the control strategy were verified. 展开更多
关键词 grinding mechanism constant force control strategy fuzzy control proportion integration differentiation(PID)
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Active traveling wave vibration control of elastic supported conical shells with smart micro fiber composites based on the differential quadrature method
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作者 Yuxin HAO Lei SUN +1 位作者 Wei ZHANG Han LI 《Applied Mathematics and Mechanics(English Edition)》 2025年第2期305-322,共18页
This paper investigates the active traveling wave vibration control of an elastic supported rotating porous aluminium conical shell(CS)under impact loading.Piezoelectric smart materials in the form of micro fiber comp... This paper investigates the active traveling wave vibration control of an elastic supported rotating porous aluminium conical shell(CS)under impact loading.Piezoelectric smart materials in the form of micro fiber composites(MFCs)are used as actuators and sensors.To this end,a metal pore truncated CS with MFCs attached to its surface is considered.Adding artificial virtual springs at two edges of the truncated CS achieves various elastic supported boundaries by changing the spring stiffness.Based on the first-order shear deformation theory(FSDT),minimum energy principle,and artificial virtual spring technology,the theoretical formulations considering the electromechanical coupling are derived.The comparison of the natural frequency of the present results with the natural frequencies reported in previous literature evaluates the accuracy of the present approach.To study the vibration control,the integral quadrature method in conjunction with the differential quadrature approximation in the length direction is used to discretize the partial differential dynamical system to form a set of ordinary differential equations.With the aid of the velocity negative feedback method,both the time history and the input control voltage on the actuator are demonstrated to present the effects of velocity feedback gain,pore distribution type,semi-vertex angle,impact loading,and rotational angular velocity on the traveling wave vibration control. 展开更多
关键词 rotating conical shell(CS) porous metal material active vibration control elastic support differential quadrature method
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Differential hydrocarbon enrichment and its major controlling factors in the southern Tethys Domain
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作者 BAI Guoping JIN Zhijun +4 位作者 HE Zhiliang ZHANG Guangya YIN Jinyin ZHU Houqin LYU Xueyan 《Petroleum Exploration and Development》 2025年第6期1439-1455,共17页
Using the latest global datasets of hydrocarbon fields and reservoirs,this study systematically investigates the characteristics of differential hydrocarbon enrichment and its primary controlling factors in the southe... Using the latest global datasets of hydrocarbon fields and reservoirs,this study systematically investigates the characteristics of differential hydrocarbon enrichment and its primary controlling factors in the southern Tethys Domain within the context of Tethys tectonic evolution.The results indicate that although the southern Tethys Domain comprises only one-third of the Tethys Domain in areal extent,it hosts nearly 80%of its total hydrocarbon reserves,exhibiting a markedly uneven distribution pattern.Specifically,the Middle East sub-segment is identified as the core enrichment area,with the Arabian Basin serving as a typical example.Through tectonic subdivision,classification of sedimentary basins,analysis of source rock distribution and reservoir-seal assemblages,as well as an integrated investigation of the relationship between succeeding paleo-uplifts and hydrocarbon enrichment,the study demonstrates that the superimposition patterns of prototype basins,the scale and distribution of source rocks,the effectiveness of reservoir-seal assemblages,and the basement paleo-uplifts are the key factors governing hydrocarbon enrichment in the southern Tethys Domain.The findings of this study provide valuable references for deeper understanding of hydrocarbon accumulation patterns in the central and northern Tethys Domain and even other global regions with similar geological settings,and offer a scientific basis for selection of favorable play fairways in the southern Tethys Domain. 展开更多
关键词 Tethys Domain Persian Gulf Arabian Basin differential hydrocarbon enrichment prototype basin source-reservoir-seal assemblage PALEO-UPLIFT hydrocarbon enrichment controlling factor
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Compact formulation of the augmented evolution equation for optimal control computation
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作者 Sheng Zhang Jiangtao Huang +2 位作者 Gang Liu Fei Liao Fangfang Hu 《Control Theory and Technology》 2026年第1期96-110,共15页
The augmented evolution equation is established under the framework of the Variation Evolving Method(VEM)that seeks optimal solutions by solving the transformed Initial-Value Problems(IVPs).To improve the numerical pe... The augmented evolution equation is established under the framework of the Variation Evolving Method(VEM)that seeks optimal solutions by solving the transformed Initial-Value Problems(IVPs).To improve the numerical performance,its compact form is developed herein.Through replacing the states and costates variation evolution with that of the controls,the dimension-reduced Evolution Partial Differential Equation(EPDE)only solves the control variables along the variation time to get the optimal solution,and the initial conditions for the definite solution may be arbitrary.With this equation,the scale of the resulting IVPs,obtained via the semi-discrete method,is significantly reduced and they may be solved with common Ordinary Differential Equation(ODE)integration methods conveniently.Meanwhile,the state and the costate dynamics share consistent stability in the numerical computation and this avoids the intrinsic numerical difficulty as in the indirect methods.Numerical examples are solved and it is shown that the compact form evolution equation outperforms the primary form in the precision,and the efficiency may be higher for the dense discretization.Actually,it is uncovered that the compact form of the augmented evolution equation is a continuous realization of the Newton type iteration mechanism. 展开更多
关键词 Optimal control Lyapunov dynamics stability Variation evolution Evolution partial differential equation Initial-value problem
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Design of PID controller with incomplete derivation based on differential evolution algorithm 被引量:16
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作者 Wu Lianghong Wang Yaonan +1 位作者 Zhou Shaowu Tan Wen 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2008年第3期578-583,共6页
To determine the optimal or near optimal parameters of PID controller with incomplete derivation, a novel design method based on differential evolution (DE) algorithm is presented. The controller is called DE-PID co... To determine the optimal or near optimal parameters of PID controller with incomplete derivation, a novel design method based on differential evolution (DE) algorithm is presented. The controller is called DE-PID controller. To overcome the disadvantages of the integral performance criteria in the frequency domain such as IAE, ISE, and ITSE, a new performance criterion in the time domain is proposed. The optimization procedures employing the DE algorithm to search the optimal or near optimal PID controller parameters of a control system are demonstrated in detail. Three typical control systems are chosen to test and evaluate the adaptation and robustness of the proposed DE-PID controller. The simulation results show that the proposed approach has superior features of easy implementation, stable convergence characteristic, and good computational efficiency. Compared with the ZN, GA, and ASA, the proposed design method is indeed more efficient and robust in improving the step response of a control system. 展开更多
关键词 PID controller incomplete derivation differential evolution parameter tuning.
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Differential Hydrocarbon Enrichment and its Main Controlling Factors in Depressions of the Bohai Bay Basin Differential Hydrocarbon Enrichment and its Main Controlling Factors in Depressions of the Bohai Bay Basin 被引量:17
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作者 JIANG Youlu LIU Hua +4 位作者 SONG Guoqi WANG Yongshi LIU Jingdong ZHAO Kai LYU Xueying 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2017年第5期1855-1872,共18页
Significant differential hydrocarbon enrichment occurs in depressions in a petroliferous basin.There are multiple depressions in the Bohai Bay Basin, and each depression as a relatively independent unit of hydrocarbon... Significant differential hydrocarbon enrichment occurs in depressions in a petroliferous basin.There are multiple depressions in the Bohai Bay Basin, and each depression as a relatively independent unit of hydrocarbon generation, migration and accumulation, contains significantly different hydrocarbon generation conditions and enrichment degree. On the basis of previous documents and a large number of statistical data, this work comparatively analyzed the differential hydrocarbon enrichment and its major controlling factors in depressions of the Bohai Bay Basin. The results show that depressions in the Bohai Bay Basin have various hydrocarbon enrichment degrees, and can be categorized into four types, namely enormously oil-rich, oil-rich, oily and oil-poor depressions. In general, the enormously oil-rich and oil-rich depressions are distributed in the eastern part of the basin along the Tan-Lu and Lan-Liao faults, whereas depressions in the western part of the basin are poor in hydrocarbons. Moreover, the vertical distribution of hydrocarbons is also highly heterogeneous, with Pre-Paleogene strata rich in hydrocarbons in the northern and western depressions, Paleogene strata rich in hydrocarbons in the entire basin, and Neogene strata rich in hydrocarbons in the off-shore areas of the Bohai Bay Basin. From early depressions in onshore areas to the late depressions in offshore areas of the Bohai Bay Basin, the source rocks and source-reservoir-cap rock assemblages gradually become younger and shallower, and the hydrocarbon resource abundance gradually increases. Hydrocarbon supplying condition is the key factor constraining the hydrocarbon enrichment for different depressions,while the main source-reservoir-cap rock assemblage, sufficient hydrocarbons and the transportation capacity of faults control the vertical distribution of hydrocarbons. The main factors controlling hydrocarbon enrichment are different for different layers. The hydrocarbon supplying condition of source rocks is the key controlling factor, whereas the source-reservoir configuration, the main sourcereservoir-cap rock assemblages, and the fault transportation are the main factors of hydrocarbon enrichment in the Paleogene, Paleogene and Neogene, respectively. 展开更多
关键词 differential hydrocarbon enrichment hydrocarbon distribution hydrocarbon-rich depression fault transportation main controlling factors Bohai Bay Basin
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Self-adapting control parameters modifieddifferential evolution for trajectoryplanning of manipulators 被引量:12
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作者 Lianghong WU Yaonan WANG Shaowu ZHOU 《控制理论与应用(英文版)》 EI 2007年第4期365-373,共9页
Control parameters of original differential evolution (DE) are kept fixed throughout the entire evolutionary process. However, it is not an easy task to properly set control parameters in DE for different optiinizat... Control parameters of original differential evolution (DE) are kept fixed throughout the entire evolutionary process. However, it is not an easy task to properly set control parameters in DE for different optiinization problems. According to the relative position of two different individual vectors selected to generate a difference vector in the searching place, a self-adapting strategy for the scale factor F of the difference vector is proposed. In terms of the convergence status of the target vector in the current population, a self-adapting crossover probability constant CR strategy is proposed. Therefore, good target vectors have a lower CFI while worse target vectors have a large CFI. At the same time, the mutation operator is modified to improve the convergence speed. The performance of these proposed approaches are studied with the use of some benchmark problems and applied to the trajectory planning of a three-joint redundant manipulator. Finally, the experiment results show that the proposed approaches can greatly improve robustness and convergence speed. 展开更多
关键词 Self-adapting control parameters differential evolution Redundant manipulator Trajectory planning
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PRINCIPLE TO CLOSED LOOP CONTROL DIFFERENTIAL CYLINDER WITH DOUBLE SPEED VARIABLE PUMPS AND SINGLE LOOP CONTROL SIGNAL 被引量:8
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作者 QuanLong NeubertT HelduserS 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2004年第1期85-88,共4页
To control the position of differential cylinder closed loop without usingany throttle elements, a flew idea that two speed variable pumps are used to compensate thenon-symmetric flow of differential cylinder is carri... To control the position of differential cylinder closed loop without usingany throttle elements, a flew idea that two speed variable pumps are used to compensate thenon-symmetric flow of differential cylinder is carried out. According to the leaking property of thesystem, a speed offset principle is also proposed to eliminate the cavitation and tension caused bythe leakage and condensation of oil, which makes the system be in the same state as a valvecontrolled circuit. This principle is explained theoretically and experimentally. Further therelationship that the pressures in cylinder chambers change with load and leakage, and therelationship between biasing speed and pre-load pressures in cylinder chambers are established. Theresearch has proved that the new system has similar technique features as those of controlled withservo valves, but due to the elimination of all the throttle lose the efficiency of system can beimproved greatly. 展开更多
关键词 Electro-hydraulic servo control Speed variable pump differential cylindersystem
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Application of PID controller to 2D differential geometric guidance problem 被引量:5
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作者 Chaoyong LI Wuxing JING 《控制理论与应用(英文版)》 EI 2007年第3期285-290,共6页
This paper presents the application of the proportional-integral-derivative (PID) controller to the flight control system (FCS) for two-dimensional (2D) differential geometric (DG) guidance and control problem... This paper presents the application of the proportional-integral-derivative (PID) controller to the flight control system (FCS) for two-dimensional (2D) differential geometric (DG) guidance and control problem. In particular, the performance of the designed FCS is investigated. To this end, the commanded angle-of-attack is firstly developed in the time domain using the classical DG formulations. Then, the classical PID controller is introduced to develop a FCS so as to form the 2D DG guidance and control system, and the PID controller parameters are determined by the Ziegler-Nichols method as well as the Routh-Hurwitz stability algorithm to guarantee the convergence of the system error. The results demonstrate that the designed controller yields a fast responding system, and the resulting DG guidance and control system is viable and effective in a realistic missile defense engagement. 展开更多
关键词 differential geometry Flight control system Missile guidance PID controller
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Novel adaptive neural control of flexible air-breathing hypersonic vehicles based on sliding mode differentiator 被引量:14
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作者 Bu Xiangwei Wu Xiaoyan +1 位作者 Ma Zhen Zhang Rui 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2015年第4期1209-1216,共8页
A novel adaptive neural control strategy is exploited for the longitudinal dynamics of a generic flexible air-breathing hypersonic vehicle(FAHV).By utilizing functional decomposition method, the dynamics of FAHV is ... A novel adaptive neural control strategy is exploited for the longitudinal dynamics of a generic flexible air-breathing hypersonic vehicle(FAHV).By utilizing functional decomposition method, the dynamics of FAHV is decomposed into the velocity subsystem and the altitude subsystem.For each subsystem, only one neural network is employed for the unknown function approximation.To further reduce the computational burden, minimal-learning parameter(MLP)technology is used to estimate the norm of ideal weight vectors rather than their elements.By introducing sliding mode differentiator(SMD) to estimate the newly defined variables, there is no need for the strict-feedback form and virtual controller.Hence the developed control law is considerably simpler than the ones derived from back-stepping scheme.Finally, simulation studies are made to illustrate the effectiveness of the proposed control approach in spite of the flexible effects, system uncertainties and varying disturbances. 展开更多
关键词 Adaptive neural control Flexible air-breathing hyper-sonic vehicle (FAHV) Flexible effects Minimal-learning parameter(MLP) Sliding mode differentiator(SMD)
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Sliding Mode Control for Fractional Differential Systems with State-delay 被引量:5
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作者 SI Jia-fang JIANG Wei 《Chinese Quarterly Journal of Mathematics》 CSCD 2012年第1期117-122,共6页
The problem of sliding mode control for fractional differential systems with statedelay is considered.A novel sliding surface is proposed and a controller is designed correspondingly,such that the state starting from ... The problem of sliding mode control for fractional differential systems with statedelay is considered.A novel sliding surface is proposed and a controller is designed correspondingly,such that the state starting from any initial value will move toward the switching surface and reach the sliding surface in finite time and the state variables on the sliding surface will converge to equilibrium point.And the stability of the proposed control design is discussed. 展开更多
关键词 sliding mode control fractional differential system TIME-DELAY
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A Simplified Sliding Mode Controlled Electronic Differential for an Electric Vehicle with Two Independent Wheel Drives 被引量:7
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作者 Azeddine Draou 《Energy and Power Engineering》 2013年第6期416-421,共6页
This paper presents a simple sliding mode control strategy used for an electronic differential system for electric vehicle with two independent wheel drives. When a vehicle drives along a curved road lane, the speed o... This paper presents a simple sliding mode control strategy used for an electronic differential system for electric vehicle with two independent wheel drives. When a vehicle drives along a curved road lane, the speed of the inner wheel has to be different from that of the outer wheel in order to prevent the vehicle from vibrating and travelling an unsteady path. Because each wheel of this electrical vehicle has independent driving force, an electrical differential system is required to replace a gear differential system. However, it is difficult to analyse the nonlinear behaviour of the differential system in relation to the speed and steering angle, as well as vehicle structure. The proposed propulsion system consists of two permanent magnet synchronous machines that ensure the drive of the two back driving wheels. The proposed control structure called independent machines for speed control allows the achievement of an electronic differential which ensures the control of the vehicle behaviour on the road. It also allows to control, independently, every driving wheel to turn at different speeds in any curve. Analysis and simulation results of the proposed system are presented in this paper. 展开更多
关键词 Electric Vehicle SLIDING Mode control Electronic differential PERMANENT MAGNET SYNCHRONOUS Motor Multimachine Multiconverter System
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EXISTENCE OF SOLUTION AND APPROXIMATE CONTROLLABILITY OF A SECOND-ORDER NEUTRAL STOCHASTIC DIFFERENTIAL EQUATION WITH STATE DEPENDENT DELAY 被引量:4
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作者 Sanjukta DAS Dwijendra PANDEY N. SUKAVANAM 《Acta Mathematica Scientia》 SCIE CSCD 2016年第5期1509-1523,共15页
This paper has two sections which deals with a second order stochastic neutral partial differential equation with state dependent delay. In the first section the existence and uniqueness of mild solution is obtained b... This paper has two sections which deals with a second order stochastic neutral partial differential equation with state dependent delay. In the first section the existence and uniqueness of mild solution is obtained by use of measure of non-compactness. In the second section the conditions for approximate controllability are investigated for the distributed second order neutral stochastic differential system with respect to the approximate controllability of the corresponding linear system in a Hilbert space. Our method is an extension of co-author N. Sukavanam’s novel approach in [22]. Thereby, we remove the need to assume the invertibility of a controllability operator used by authors in [5], which fails to exist in infinite dimensional spaces if the associated semigroup is compact. Our approach also removes the need to check the invertibility of the controllability Gramian operator and associated limit condition used by the authors in [20], which are practically difficult to verify and apply. An example is provided to illustrate the presented theory. 展开更多
关键词 approximate controllability cosine family state dependent delay neutral stochastic differential equation measure of noncompactness
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Approximate Controllability of Second-Order Neutral Stochastic Differential Equations with Infinite Delay and Poisson Jumps 被引量:4
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作者 PALANISAMY Muthukumar CHINNATHAMBI Rajivganthi 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2015年第5期1033-1048,共16页
The modelling of risky asset by stochastic processes with continuous paths, based on Brow- nian motions, suffers from several defects. First, the path continuity assumption does not seem reason- able in view of the po... The modelling of risky asset by stochastic processes with continuous paths, based on Brow- nian motions, suffers from several defects. First, the path continuity assumption does not seem reason- able in view of the possibility of sudden price variations (jumps) resulting of market crashes. A solution is to use stochastic processes with jumps, that will account for sudden variations of the asset prices. On the other hand, such jump models are generally based on the Poisson random measure. Many popular economic and financial models described by stochastic differential equations with Poisson jumps. This paper deals with the approximate controllability of a class of second-order neutral stochastic differential equations with infinite delay and Poisson jumps. By using the cosine family of operators, stochastic analysis techniques, a new set of sufficient conditions are derived for the approximate controllability of the above control system. An example is provided to illustrate the obtained theory. 展开更多
关键词 Approximate controllability Hilbert space Poisson jumps second-order neutral stochas-tic differential equations semigroup theory.
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On the finite horizon Nash equilibrium solution in the differential game approach to formation control 被引量:3
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作者 JOND Hossein Barghi NABIYEV Vasif 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2019年第6期1233-1242,共10页
The solvability of the coupled Riccati differential equations appearing in the differential game approach to the formation control problem is vital to the finite horizon Nash equilibrium solution.These equations(if so... The solvability of the coupled Riccati differential equations appearing in the differential game approach to the formation control problem is vital to the finite horizon Nash equilibrium solution.These equations(if solvable)can be solved numerically by using the terminal value and the backward iteration.To investigate the solvability and solution of these equations the formation control problem as the differential game is replaced by a discrete-time dynamic game.The main contributions of this paper are as follows.First,the existence of Nash equilibrium controls for the discretetime formation control problem is shown.Second,a backward iteration approximate solution to the coupled Riccati differential equations in the continuous-time differential game is developed.An illustrative example is given to justify the models and solution. 展开更多
关键词 formation control differential game dynamic game Nash equilibrium coupled Riccati equations.
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Inducing human induced pluripotent stem cell differentiation through embryoid bodies:A practical and stable approach 被引量:8
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作者 Ning-Ning Guo Li-Ping Liu +1 位作者 Yun-Wen Zheng Yu-Mei Li 《World Journal of Stem Cells》 SCIE 2020年第1期25-34,共10页
Human induced pluripotent stem cells(hiPSCs)are invaluable resources for producing high-quality differentiated cells in unlimited quantities for both basic research and clinical use.They are particularly useful for st... Human induced pluripotent stem cells(hiPSCs)are invaluable resources for producing high-quality differentiated cells in unlimited quantities for both basic research and clinical use.They are particularly useful for studying human disease mechanisms in vitro by making it possible to circumvent the ethical issues of human embryonic stem cell research.However,significant limitations exist when using conventional flat culturing methods especially concerning cell expansion,differentiation efficiency,stability maintenance and multicellular 3D structure establishment,differentiation prediction.Embryoid bodies(EBs),the multicellular aggregates spontaneously generated from iPSCs in the suspension system,might help to address these issues.Due to the unique microenvironment and cell communication in EB structure that a 2D culture system cannot achieve,EBs have been widely applied in hiPSC-derived differentiation and show significant advantages especially in scaling up culturing,differentiation efficiency enhancement,ex vivo simulation,and organoid establishment.EBs can potentially also be used in early prediction of iPSC differentiation capability.To improve the stability and feasibility of EB-mediated differentiation and generate high quality EBs,critical factors including iPSC pluripotency maintenance,generation of uniform morphology using micro-pattern 3D culture systems,proper cellular density inoculation,and EB size control are discussed on the basis of both published data and our own laboratory experiences.Collectively,the production of a large quantity of homogeneous EBs with high quality is important for the stability and feasibility of many PSCs related studies. 展开更多
关键词 Induced pluripotent stem cells Suspension culture Embryoid body Early prediction Committed differentiation HETEROGENEITY Three-dimensional culture SCALING-UP Quality control
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