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T(0,4)系统中等轴双曲线根轨迹的判定 被引量:1
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作者 王泽南 《农机化研究》 北大核心 2003年第2期115-115,135,共2页
在经典控制论的根轨迹研究中,解析法是对通用的图解法的一种补充。利用解析法对T(0,4)系统根轨迹进行了研判,导出了在系数满足一定条件时根轨迹为等轴双曲线的结论。
关键词 t(0 4)系统 等轴双曲线 根轨迹 解析法 常微分方程
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商场冷凝水耦合光伏/光热系统在不同气候区的适宜性研究
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作者 张长兴 许冲 +2 位作者 路希正 吴相杰 彭冬根 《科学技术与工程》 北大核心 2024年第16期6718-6725,共8页
光伏光热技术是太阳能的主要利用方式之一,太阳能光伏光热一体化(solar photovoltaic-thermal,PV/T)系统可实现系统产电和热量的双重效益。基于不同气候区的气候特征,以商场冷凝水耦合光伏/光热系统为研究对象。在确定制冷季冷凝水量的... 光伏光热技术是太阳能的主要利用方式之一,太阳能光伏光热一体化(solar photovoltaic-thermal,PV/T)系统可实现系统产电和热量的双重效益。基于不同气候区的气候特征,以商场冷凝水耦合光伏/光热系统为研究对象。在确定制冷季冷凝水量的基础上,计算分析系统一次能源节约率及环境效益,研究该系统在不同气候区的适宜性。结果表明:在寒冷地区、夏热冬冷地区和夏热冬暖地区,PV/T系统比光伏(photovoltaic,PV)系统更加高效节能。在整个制冷季中,PV/T系统的发电量均高于PV系统,海口的发电效率提升了0.53%,拉萨的发电效率提升了0.11%;PV/T系统在海口地区一次能源节约率最高,达到59.62%;青岛CO_(2)减排量最高,总减排量达到5.5 t。 展开更多
关键词 光伏光热一体化(PV/t)系统 冷凝水 太阳辐射 一次能源节约率 CO_(2)减排量
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FUZZY ROBUST H_∞ CONTROL OF UNCERTAIN NONLINEAR SYSTEM WITH TIME-DEALY 被引量:3
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作者 刘亚 胡寿松 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2002年第2期123-126,共4页
This paper addresses the problem of the fuzzy H ∞state feedback control for a class of uncertain nonlinear systems with time delay. The Takagi Sugeno (T S) mo del with time delay and parameter uncertainties is ... This paper addresses the problem of the fuzzy H ∞state feedback control for a class of uncertain nonlinear systems with time delay. The Takagi Sugeno (T S) mo del with time delay and parameter uncertainties is adopted for modeling of nonlinear system. The systematic design procedure for the fuzzy robust controller based on linear matrix inequality (LMI) is given. Some sufficient conditions are derived for the existence of fuzzy H ∞ state feedback controllers such that the closed loop system is asymptotically stable and the effect of the disturbance input on controlled output is reduced to a prescribed level. An example is given to demonstrate the effectiveness of the proposed method. 展开更多
关键词 UNCERtAINtY time delay t S fuzzy model linear matrix inequality (LMI)
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Chaos Control in a New Three-Dimensional Chaotic T System 被引量:5
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作者 CHEN Yong YAN Zhen-Ya 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第4期951-954,共4页
In this paper, we study chaos control of the new 3D chaotic system. We use three feedback methods (the linear, speed, doubly-periodic function controller) to suppress the chaos to unstable equilibrium. As a result, ... In this paper, we study chaos control of the new 3D chaotic system. We use three feedback methods (the linear, speed, doubly-periodic function controller) to suppress the chaos to unstable equilibrium. As a result, some controllers are obtained. Moreover, numerical simulations are used to verify the effectiveness of the obtained controllers. 展开更多
关键词 chaos control chaotic t system feedback control Routh-Hurwitz theorem numerical simulation
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Interaction between antigen presenting cells and autoreactive T cells derived from BXSB mice with murine lupus 被引量:2
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作者 Peng Yang Bo Li +2 位作者 Ping Lv Yan Zhang Xiao-Ming Gao, Department of Immunology, Peking University Health Science Center, Peking University, 38 Xueyuan Rd, Beijing 100083, China 《Cell Research》 SCIE CAS CSCD 2007年第6期556-564,共9页
Systemic lupus erythematosus (SLE) is a typical autoimmune disease involving multiple systems and organs. Ample evidence suggests that autoreactive T cells play a pivotal role in the development of this autoimmune d... Systemic lupus erythematosus (SLE) is a typical autoimmune disease involving multiple systems and organs. Ample evidence suggests that autoreactive T cells play a pivotal role in the development of this autoimmune disorder. This study was undertaken to investigate the mechanisms of interaction between antigen presenting cells (APCs) and an autoreactive T cell (ATLI) clone obtained from lupus-prone BXSB mice. ATLI cells, either before or after 7-ray irradiation, were able to activate naive B cells, as determined by B cell proliferation assays. Macrophages from BXSB mice were able to stimulate the proliferation of resting ATL 1 cells at a responder/stimulator (R/S) ratio of 1/2.5. Dendritic cells (DCs) were much more powerful stimulators for ATLI cells on a per cell basis. The T cell stimulating ability ofmacrophages and B cells, but not DCs, was sensitive to T-ray irradiation. Monoclonal antibodies against mouse MHC-Ⅱ and CD4 were able to block DC-mediated stimulation of ATL 1 proliferation, indicating cognate recognition between ATL 1 and APCs. Our data suggest that positive feedback loops involving macrophages, B cells and autoreactive T cells may play a pivotal role in keeping the momentum of autoimmune responses leading to autoimmune diseases. 展开更多
关键词 SLE t cells antigen presenting cells
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Downregulation of CD4+CD25+ regulatory T cells may underlie enhanced Th1 immunity caused by immunization with activated autologous T cells 被引量:5
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作者 Qi Cao Li Wang +8 位作者 Fang Du Huiming Sheng Yan Zhang Juanjuan Wu Baihua Shen TianweiShen Jingwu Zhang Dangsheng Li Ningli Li 《Cell Research》 SCIE CAS CSCD 2007年第7期627-637,共11页
Regulatory T cells (Treg) play important roles in immune system homeostasis, and may also be involved in tumor immunotolerance by suppressing Th1 immune response which is involved in anti-tumor immunity. We have pre... Regulatory T cells (Treg) play important roles in immune system homeostasis, and may also be involved in tumor immunotolerance by suppressing Th1 immune response which is involved in anti-tumor immunity. We have previously reported that immunization with attenuated activated autologous T cells leads to enhanced anti-tumor immunity and upregulated Thl responses in vivo. However, the underlying molecular mechanisms are not well understood. Here we show that Treg function was significantly downregulated in mice that received immunization of attenuated activated autologous T cells. We found that Foxp3 expression decreased in CD4+CD25+ T cells from the immunized mice. Moreover, CD4+CD25+Foxp3+ Treg obtained from immunized mice exhibited diminished immunosuppression ability compared to those from naive mice. Further analysis showed that the serum of immunized mice contains a high level ofanti-CD25 antibody (about 30 ng/ml, p〈0.01 vs controls). Consistent with a role ofanti-CD25 response in the downregulation of Treg, adoptive transfer of serum from immunized mice to naive mice led to a significant decrease in Treg population and function in recipient mice. The triggering of anti-CD25 response in immunized mice can be explained by the fact that CD25 was induced to a high level in the ConA activated autologous T cells used for immunization. Our results demonstrate for the first time that immunization with attenuated activated autologous T cells evokes anti-CD25 antibody production, which leads to impeded CD4+CD25+Foxp3+ Treg expansion and function in vivo. We suggest that dampened Treg function likely contributes to enhanced Thl response in immunized mice and is at least part of the mechanism underlying the boosted anti-tumor immunity. 展开更多
关键词 immunization with activated autologous t cells CD4+CD25+Foxp3+ treg anti-CD25 antibody serum adoptive transfer
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100G Transport Systems: Technology Bench-Mark Testing in China and Evolution to Terabit/s Interfaces 被引量:1
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作者 张晓宏 易小波 +1 位作者 刘翔 Peter J.Winzer 《China Communications》 SCIE CSCD 2013年第4期19-30,共12页
To meet the exponentially growing demand fbr bandwidth in Optical Transport Networks (OTNs), 100-Gb/s (100G) coherent technology based oil Polarization-Division Multiplexed Quadrature Phase Shift Keying (PDM-QPSK... To meet the exponentially growing demand fbr bandwidth in Optical Transport Networks (OTNs), 100-Gb/s (100G) coherent technology based oil Polarization-Division Multiplexed Quadrature Phase Shift Keying (PDM-QPSK), which enables the capacity of a Wavelength Division Multiplexing (WDM) system to approach 10 Tb/s, is being widely deployed globally. As the first vendor to intro- duce a single-carrier 100G solution, A1- catel-Lucent has developed key transponder and network management technologies, which are reviewed in this paper together with their commercial evolution to 400G. Focusing on the Chinese market, we also review some key bench-mark testing results obtained in partner- ship with major Chinese operators. Finally, we discuss enabling technologies that are currently being researched to allow interfaces to scale to Terabit/s rates. 展开更多
关键词 WDM transmission digital co-herent detection advanced modulation for-mats: wavelength monitoring superchannel
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Min-max fuzzy model predictive tracking control of boiler-turbine system for ultra-supercritical units 被引量:1
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作者 Chen Chen Pan Lei Kwang Y.Lee 《Journal of Southeast University(English Edition)》 EI CAS 2021年第1期42-51,共10页
To improve the control performance of nonlinear ultra-supercritical(USC)thermal power units,an improved min-max fuzzy model predictive tracking control(FMPTC)strategy is proposed.First,a T-S fuzzy model is established... To improve the control performance of nonlinear ultra-supercritical(USC)thermal power units,an improved min-max fuzzy model predictive tracking control(FMPTC)strategy is proposed.First,a T-S fuzzy model is established to approximate the dynamics of the nonlinear boiler-turbine system.Then,based on an extended fuzzy model containing state variables and output variables,a min-max FMPTC is derived for output regulation while ensuring the closed-loop system stability and the inputs in their given constraints.For greater controller design freedom,the developed controller adopts a new state-and output-based objective function.In addition,the observer estimation error is regarded as a bounded disturbance,ensuring the stability of the entire closed-loop control system.Simulation results on a 1000 MW USC boiler-turbine model illustrate the effectiveness of the proposed approach. 展开更多
关键词 ultra-supercritical boiler-turbine system t-S model min-max model predictive control output tracking linear matrix inequality
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Traffic Forecasting Model Based on Takagi-Sugeno Fuzzy Logical System
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作者 王维工 李征 程美玲 《Journal of Donghua University(English Edition)》 EI CAS 2005年第1期129-132,共4页
The local multiple regression fuzzy(LMRF)model based on Takagi-Sugeno fuzzy logical system and its application in traffic forecasting is proposed. Besides its prediction accuracy is testified and the model is proved m... The local multiple regression fuzzy(LMRF)model based on Takagi-Sugeno fuzzy logical system and its application in traffic forecasting is proposed. Besides its prediction accuracy is testified and the model is proved much better than conventional forecasting methods. According to the regional traffic system, the model perfectly states the complex non-linear relation of the traffic and the local social economy. The model also efficiently deals with the system lack of enough data. 展开更多
关键词 t-S model traffic forecasting LMRF model.
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SME share transfer system financing Efficiency Analysis
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作者 CUI Jinxing 《International English Education Research》 2016年第5期7-9,共3页
SME share transfer system financing has become the main theme of a new three-panel market.The efficiency of the new board of corporate finance and has become the core focus, more controversial aspects.SMEs in SME shar... SME share transfer system financing has become the main theme of a new three-panel market.The efficiency of the new board of corporate finance and has become the core focus, more controversial aspects.SMEs in SME share transfer system market mainly private placement financing, equity financing pledge, and Transfer of Listing and mergers and acquisitions.This paper will be discussed by comparing the SMEs through SME share transfer system market financing, the use of a single sample T-test (One-Sample T Test) to verify the efficiency of the new board of corporate finance assets problem. 展开更多
关键词 SME share transfer system SMES financing efficiency
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A research on an energy-saving software for pumping units based on FNN intelligent control
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作者 丁宝 齐维贵 王凤平 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2004年第3期240-244,共5页
An energy-saving scheme for pumping units via intermission start-stop performance is proposed. Because of the complexity of the oil extraction process, Fuzzy Neural Network (FNN) intelligent control is adopted. The st... An energy-saving scheme for pumping units via intermission start-stop performance is proposed. Because of the complexity of the oil extraction process, Fuzzy Neural Network (FNN) intelligent control is adopted. The structure of the Takagi-Sugeno (T-S) fuzzy neural network model is introduced and modified. FNNs are trained with sample information from oil fields and expert knowledge. Finally, pumping unit energy-saving FNN software, which cuts down power costs substantially, is presented. 展开更多
关键词 rocker pumping unit t-S fuzzy system fuzzy neural network BP algorithm
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Role of nuclear receptor NR4A2 in gastrointestinal inflammation and cancers 被引量:7
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作者 Yi-Fang Han Guang-Wen Cao 《World Journal of Gastroenterology》 SCIE CAS CSCD 2012年第47期6865-6873,共9页
NR4A2 is a transcription factor belonging to the steroid orphan nuclear receptor superfamily.It was originally considered to be essential in the generation and maintenance of dopaminergic neurons,and associated with n... NR4A2 is a transcription factor belonging to the steroid orphan nuclear receptor superfamily.It was originally considered to be essential in the generation and maintenance of dopaminergic neurons,and associated with neurological disorders such as Parkinson's disease.Recently,NR4A2 has been found to play a critical role in some inflammatory diseases and cancer.NR4A2 can be efficiently trans-activated by some proinflammatory cytokines,such as tumor necrosis factor-α,interleukin-1β,and vascular endothelial growth factor(VEGF).The nuclear factor-κB signaling pathway serves as a principal regulator of inducible NR4A expression in immune cells.NR4A2 can trans-activate Foxp3,a hallmark specifically expressed in regulatory T(Treg) cells,and plays a critical role in the differentiation,maintenance,and function of Treg cells.NR4A2 in T lymphocytes is pivotal for Treg cell induction and suppression of aberrant induction of Th1 under physiological and pathological conditions.High density of Foxp3 + Treg cells is significantly associated with gastrointestinal inflammation,tumor immune escape,and disease progression.NR4A2 is produced at high levels in CD133 + colorectal carcinoma(CRC) cells and significantly upregulated by cyclooxygenase-2-derived prostaglandin E 2 in a cyclic adenosine monophosphate(cAMP)/protein kinase A(PKA)-dependent manner in CRC cells.The cAMP/PKA signaling pathway is the common pathway of NR4A2-related inflammation and cancer.NR4A2 trans-activates osteopontin,a direct target of the Wnt/β-catenin pathway associated with CRC invasion,metastasis,and poor prognosis.Knockdown of endogenous NR4A2 expression attenuates VEGF-induced endothelial cell proliferation,migration and in vivo angiogenesis.Taken together,NR4A2 emerges as an important nuclear factor linking gastrointestinal inflammation and cancer,especially CRC,and should serve as a candidate therapeutic target for inflammation-related gastrointestinal cancer. 展开更多
关键词 NR4A2 INFLAMMAtION Immune cells Signaling pathway Gastrointestinal carcinoma
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Correlation between CD4^+CD25^+Treg Cells and CCR4 in Nasopharyngeal Carcinoma 被引量:1
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作者 Yan-xin REN Jun SUI +5 位作者 Xin SONG Gee WAN WONG Jing MA Hong YAO Marie Chia-mi LIN Xiao-jiang LI 《Clinical oncology and cancer researeh》 CAS CSCD 2011年第2期106-113,共8页
OBJECTIVE CD4^+CD25^+ T regulatory (Treg) cells are a population of T cells which suppress an overactive immune system. CCR4 is a chemokine receptor involved in the recruitment of lymphocytes. Nasopharyngeal carci... OBJECTIVE CD4^+CD25^+ T regulatory (Treg) cells are a population of T cells which suppress an overactive immune system. CCR4 is a chemokine receptor involved in the recruitment of lymphocytes. Nasopharyngeal carcinoma (NPC) is resistant to immunosurveillance, owing to the increased number of tumor-infiltrating Treg cells which are recruited to the tumor bv CCR4. 展开更多
关键词 nasopharyngeal carcinoma CD4^+CD25^+ treg cells CCR4 flow cytometry tumor-infiltrating lymphocytes.
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基于有限射影平面上(ω,r,d)-CFF(N,T)系统的构作
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作者 陈海霞 胡海燕 《数学的实践与认识》 2021年第4期319-323,共5页
在有限射影平面上利用有限射影平面的性质构作了(ω,r,d)-CFF(N,T)系统,并利用有限射影平面的性质计算了它的参数.最后利用一个有限点集构作了一个(ω,r,d)-DS(N,T)系统并计算了它的参数.
关键词 有限射影平面 r d)-CFF(N t)系统 r d)-DS(N t)系统
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玻璃盖板与光伏板间距对PV/T系统性能的影响 被引量:1
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作者 周青山 张志刚 《煤气与热力》 2019年第8期7-11,J0041,共6页
通过对PV/T系统中的光伏板和玻璃盖板进行热平衡分析,探讨光伏板与玻璃盖板之间的板间距对PV/T系统光热效率的影响。根据天津地区典型年气象参数,计算出在不同的板间距不同光伏板温度的情况下,PV/T系统中光伏板散热量和光热效率,对计算... 通过对PV/T系统中的光伏板和玻璃盖板进行热平衡分析,探讨光伏板与玻璃盖板之间的板间距对PV/T系统光热效率的影响。根据天津地区典型年气象参数,计算出在不同的板间距不同光伏板温度的情况下,PV/T系统中光伏板散热量和光热效率,对计算结果进行分析。随着板间距变大,PV/T系统的光热效率开始快速升高,达到极大值后随着板间距继续增加,光热效率有所下降,下降到一定程度后又有所上升。PV/T系统中光伏板散热量的变化趋势与此相反。对所分析的两种光伏板温度(40℃、50℃),最佳板间距随着光伏板温度的升高而减小。当光伏板的温度控制在40℃时最佳板间距为6 cm,当光伏板的温度控制在50℃时最佳板间距为5 cm。由于调节板间距容易实现,所以选择合适的板间距对提高PV/T系统的光热效率有实用价值。 展开更多
关键词 光伏光热一体化(PV/t)系统 板间距 光热效率 玻璃盖板 散热量
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利用辛空间上子空间构作(ω,r,d)-CFF(N,T)
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作者 李素芳 《数学的实践与认识》 CSCD 北大核心 2011年第11期241-244,共4页
利用辛空间上m维(m,s)型子空间的性质构作了(w,r,d)-CFF(N,T)系统,并利用子空间的计数定理计算了它的参数.一个(ω,r,d)-CFF(N,T)系统在许多领域有着极为广泛的应用.
关键词 r d)-CFF(N t)系统 r d)-DS(N t)系统 有限辛空间 (m s) 型子空间
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Mixing via the extended family
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作者 KUANG Rui 《Science China Mathematics》 SCIE 2014年第2期367-376,共10页
In this paper,the relationship between the extended family and several mixing properties in measuretheoretical dynamical systems is investigated.The extended family eF related to a given family F can be regarded as th... In this paper,the relationship between the extended family and several mixing properties in measuretheoretical dynamical systems is investigated.The extended family eF related to a given family F can be regarded as the collection of all sets obtained as"piecewise shifted"members of F.For a measure preserving transformation T on a Lebesgue space(X,B,μ),the sets of"accurate intersections of order k"defined below are studied,Nε(A0,A1,...,Ak)=n∈Z+:μk i=0T inAiμ(A0)μ(A1)μ(Ak)<ε,for k∈N,A0,A1,...,Ak∈B and ε>0.It is shown that if T is weakly mixing(mildly mixing)then for any k∈N,all the sets Nε(A0,A1,...,Ak)have Banach density 1(are in(eFip),i.e.,the dual of the extended family related to IP-sets). 展开更多
关键词 FAMILY the extended family weak mixing mild mixing order
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Adoptive therapy with CAR redirected T cells for hematological malignancies 被引量:11
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作者 Shiqi Li Zhi Yang +2 位作者 Junjie Shen Juanjuan Shan Cheng Qian 《Science China(Life Sciences)》 SCIE CAS CSCD 2016年第4期370-378,共9页
The survival of patients with hematological malignancies has been significantly improved due to the development of new therapeutic agents. However, relapse remains a major matter for concern. Recently, T cells enginee... The survival of patients with hematological malignancies has been significantly improved due to the development of new therapeutic agents. However, relapse remains a major matter for concern. Recently, T cells engineered with chimeric antigen receptor(CAR) were reported to show unprecedented responses in a range of hematological malignancies. The persistence of the CAR-T cell can last for years and tends toward long-term antitumor memory by which relapses can be effectively prevented. The primary side effects that appear in most clinical trials are cytokine release syndrome and neurotoxicity. However, these symptoms can be treated and reversed. In this review, we describe CAR structure and function and summarize recent advances in CAR-T cell therapy in hematological malignancies. 展开更多
关键词 cancer hematological malignancies immunotherapy chimeric antigen receptor t-cell therapy
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Output Consensus for Heterogeneous Nonlinear Multi-Agent Systems Based on T-S Fuzzy Model 被引量:3
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作者 LI Xiaolei LUO Xiaoyuan +1 位作者 LI Shaobao GUAN Xinping 《Journal of Systems Science & Complexity》 SCIE EI CSCD 2017年第5期1042-1060,共19页
In this paper, the output consensus problem of general heterogeneous nonlinear multi-agent systems subject to different disturbances is considered. A kind of Takagi-Sukeno fuzzy modeling method is used to describe the... In this paper, the output consensus problem of general heterogeneous nonlinear multi-agent systems subject to different disturbances is considered. A kind of Takagi-Sukeno fuzzy modeling method is used to describe the nonlinear agents' dynamics. Based on the model, a distributed fuzzy observer and controller are designed based on parallel distributed compensation scheme and internal reference models such that the heterogeneous nonlinear multi-agent systems can achieve output consensus. Then a necessary and sufficient condition is presented for the output consensus problem. And it is shown that the consensus trajectory of the global fuzzy model is determined by the network topology and the initial states of the internal reference models. Finally, some simulations are given to illustrate and verify the effectiveness of the proposed scheme. 展开更多
关键词 Heterogeneous nonlinear multi-agent system internal reference model output consensus t-S fuzzy model.
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