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基于动态优化模型集的多模型自适应控制 被引量:7
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作者 李锋 周有训 《计算机测量与控制》 CSCD 2005年第2期138-140,共3页
针对多模型自适应控制的传统算法中固定模型集无法准确覆盖对象的不确定域的问题,提出了一种新型的能够在线动态优化模型集的方法。该方法能够在线自动添加、删除以及修改模型集中的模型,有效地控制模型数量以及优化模型集,使模型集对... 针对多模型自适应控制的传统算法中固定模型集无法准确覆盖对象的不确定域的问题,提出了一种新型的能够在线动态优化模型集的方法。该方法能够在线自动添加、删除以及修改模型集中的模型,有效地控制模型数量以及优化模型集,使模型集对不确定域进行精确覆盖,并且在系统运行的稳定阶段可以停止优化模型集的动作,从而大幅减少计算量。该方法在优化控制性能的同时不会过分增加系统运算负担,仿真实验表明了此算法的优越性。 展开更多
关键词 模型自适应控制 动态优化模型 线性模型 模型
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MOSFET的大信号动态集总模型及射频电路模拟
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作者 陈宰曼 来金梅 +2 位作者 任俊彦 许俊 Omar Wing 《固体电子学研究与进展》 CAS CSCD 北大核心 2004年第1期44-49,共6页
针对 RF电路模拟的需要 ,在文中提出了一个基于表面势的 MOSFET大信号动态集总模型。这个模型是由 MOSFET的 PDE模型简化推导而来。它不仅比传统的模型能更精确地描述晶体管在高频大信号情况下的伏 -安特性 ,而且比 PDE模型易于求解 ,... 针对 RF电路模拟的需要 ,在文中提出了一个基于表面势的 MOSFET大信号动态集总模型。这个模型是由 MOSFET的 PDE模型简化推导而来。它不仅比传统的模型能更精确地描述晶体管在高频大信号情况下的伏 -安特性 ,而且比 PDE模型易于求解 ,从而大大提高了电路模拟的速度。通过模拟几个具体的 RF电路 ,将这个模型与 PDE模型作了比较 ,结果表明两者吻合得很好。 展开更多
关键词 MOSFET 表面势 大信号动态模型 射频电路 偏微分方程
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600MW超临界锅炉半辐射受热面积灰监测模型研究 被引量:3
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作者 徐力刚 黄亚继 +1 位作者 岳峻峰 陈波 《动力工程学报》 CAS CSCD 北大核心 2015年第11期871-877,共7页
针对燃煤锅炉受热面积灰监测的需求,以某电厂600 MW锅炉的半辐射受热面为研究对象,采用污染率作为受热面积灰监测指标建立了监测模型,提出了一种高温区域烟气温度推算方法,在变负荷工况下考虑了锅炉运行动态特性并引入集总参数动态修正... 针对燃煤锅炉受热面积灰监测的需求,以某电厂600 MW锅炉的半辐射受热面为研究对象,采用污染率作为受热面积灰监测指标建立了监测模型,提出了一种高温区域烟气温度推算方法,在变负荷工况下考虑了锅炉运行动态特性并引入集总参数动态修正模型,研究了稳定负荷和变负荷工况下半辐射受热面的污染率变化趋势.结果表明:稳定负荷下的积灰监测模型能够满足积灰监测的要求,而变负荷工况下的积灰监测模型虽然在一定程度上缓解了负荷变化的影响,但污染率计算结果波动较大,仍受到负荷变化的干扰. 展开更多
关键词 超临界锅炉 半辐射受热面 积灰监测 污染率 变负荷 总参数动态修正模型
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一种改进的两阶段目标跟踪方法
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作者 王静 王琰 杨大为 《沈阳理工大学学报》 CAS 2015年第2期16-22,共7页
针对动态场景中使用固定模板进行跟踪容易丢失目标的问题以及利用动态模型估计目标位置时产生的漂移问题,提出一种改进的基于偏最小二乘法的两阶段目标跟踪方法。该方法利用偏最小二乘分析法对在高维特征空间中搜集的正负样本降维,获得... 针对动态场景中使用固定模板进行跟踪容易丢失目标的问题以及利用动态模型估计目标位置时产生的漂移问题,提出一种改进的基于偏最小二乘法的两阶段目标跟踪方法。该方法利用偏最小二乘分析法对在高维特征空间中搜集的正负样本降维,获得特征子空间构建目标表观模型集。跟踪在贝叶斯推理框架下进行:在初始跟踪阶段,利用粒子滤波原理及似然函数估计目标的初步位置;在校正阶段,采用一种适应性的基准模型确定最终的目标位置。对一些视频序列的实验结果证明了所提出方法的有效性。 展开更多
关键词 目标跟踪 偏最小二乘法 粒子滤波 动态模型集 基准模型
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现代油藏精细描述技术和方法 被引量:11
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作者 夏朝晖 余国清 +2 位作者 石宁 冯英 吴淑华 《内蒙古石油化工》 CAS 2000年第2期195-199,共5页
现代油藏描述的突出特点是其整体性、综合性、预测性、阶段性、先进性和早入性。而精细描述和预测是油田不断深入开发的必然要求 ,与早中期的油藏描述相比 ,它不仅表现在精细程度高、基本单元小 (流动单元 )、预测性强等特点 ,而且正在... 现代油藏描述的突出特点是其整体性、综合性、预测性、阶段性、先进性和早入性。而精细描述和预测是油田不断深入开发的必然要求 ,与早中期的油藏描述相比 ,它不仅表现在精细程度高、基本单元小 (流动单元 )、预测性强等特点 ,而且正在形成一套油藏精细描述的技术地质知识库建立和应用 ,地质统计学尤其随机模拟技术、动态、集成化的油藏模型建立技术 ,开发地震技术中的地震反演 (储层横向预测 )技术 ,全三维地震精细解释与可视化技术、四维地震、井间地震等技术 ,多功能综合性一体化三维油藏描述软件等技术方法最具代表性 。 展开更多
关键词 油藏描述 油藏精细描述 层次界面分析法 流动单元 地质知识库 地质统计学尤其随机摸拟技术 动态成化的油藏模型建立技术 开发地震
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A Hierarchical Virus Immunization Method for Community Networks 被引量:1
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作者 FU Cai LI Min ZHANG Yunhe ZOU Deqing HAN Lansheng 《China Communications》 SCIE CSCD 2014年第9期148-159,共12页
Due to the enormous harm of virus propagation,research regarding virus immunizations still absolutely necessary.In comparison to current researches,a new virus immunization method the hierarchical virus immunization m... Due to the enormous harm of virus propagation,research regarding virus immunizations still absolutely necessary.In comparison to current researches,a new virus immunization method the hierarchical virus immunization method(HVIM) for community networks is proposed.Based on the virus transmission dynamic model SusceptibleInfectious-Removed and SusceptibleRemoved(SIRSR),HVIM considered the influence of external factors on the spread of viruses and only needs a portion of the network structure to be able to carry out immunization.Another pro for HVIM is that it is scalable and suitable for parallel computing which is a requirement in the big data era.Finally,a simulation dataset and a real dataset were used to run experiments,and the results of simulation showed that HVIM obviously is superior to others on the aspect of immunity. 展开更多
关键词 Community Networks VirusPropagation SIRSR Model HierarchicalVirus Immunization Method (HVIM)
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Factors Acquisition and Content Estimation of Farmland Soil Organic Carbon Based upon Internet of Things 被引量:1
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作者 WU Qiulan LIANG Yong +3 位作者 LI Ying WANG Xizhi YANG Lei WANG Xiaotong 《Chinese Geographical Science》 SCIE CSCD 2017年第3期431-440,共10页
Aiming at the shortage of sufficient continuous parameters for using models to estimate farmland soil organic carbon(SOC) content, an acquisition method of factors influencing farmland SOC and an estimation method of ... Aiming at the shortage of sufficient continuous parameters for using models to estimate farmland soil organic carbon(SOC) content, an acquisition method of factors influencing farmland SOC and an estimation method of farmland SOC content with Internet of Things(IOT) are proposed in this paper. The IOT sensing device and transmission network were established in a wheat demonstration base in Yanzhou Distict of Jining City, Shandong Province, China to acquire data in real time. Using real-time data and statistics data, the dynamic changes of SOC content between October 2012 and June 2015 was simulated in the experimental area with SOC dynamic simulation model. In order to verify the estimation results, potassium dichromate external heating method was applied for measuring the SOC content. The results show that: 1) The estimated value matches the measured value in the lab very well. So the method is feasible in this paper. 2) There is a clear dynamic variation in the SOC content at 0.2 m soil depth in different growing periods of wheat. The content reached the highest level during the sowing period, and is lowest in the flowering period. 3) The SOC content at 0.2 m soil depth varies in accordance with the amount of returned straw. The larger the amount of returned straw is, the higher the SOC content. 展开更多
关键词 Internet of Things(IOT) soil organic carbon(SOC) factors acquisition SOC content estimation Soil-C model
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Semantic-based dynamic positioning mechanism for problem solving in multi-agent systems
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作者 李青山 褚华 +1 位作者 薛宝叶 张超 《Journal of Central South University》 SCIE EI CAS 2014年第2期618-628,共11页
In multi-agent systems(MAS),finding agents which are able to service properly in an open and dynamic environment are the key issue in problem solving.However,it is difficult to find agent resources quickly and positio... In multi-agent systems(MAS),finding agents which are able to service properly in an open and dynamic environment are the key issue in problem solving.However,it is difficult to find agent resources quickly and position agents accurately and complete the system integration by the keyword matching method,due to the lack of clear semantic information of the classical agent model.An semantic-based agent dynamic positioning mechanism was proposed to assist in the system dynamic integration.According to the semantic agent model and the description method,a two-stage process including the domain positioning stage and the service semantic matching positioning stage,was discussed.With this mechanism,proper agents that provide appropriate service to assign sub-tasks for task completion can be found quickly and accurately.Finally,the effectiveness of the positioning mechanism was validated through the in-depth performance analysis in the application of simulation experiments to the system dynamic integration. 展开更多
关键词 multi-agent systems(MAS) task revolution SEMANTICS dynamic location
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Vehicles PEMFC Power System Mathematical Model for Integrated Design
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作者 Vincenzo Di Dio Diego La Cascia Rosario Liga Rosario Miceli 《Journal of Energy and Power Engineering》 2013年第4期746-751,共6页
In this paper, the mathematical dynamical model of a PEMFC (proton exchange membrane fuel cells) stack, integrated with an automotive synchronous electrical power drive, developed in Matlab environment, is shown. Lo... In this paper, the mathematical dynamical model of a PEMFC (proton exchange membrane fuel cells) stack, integrated with an automotive synchronous electrical power drive, developed in Matlab environment, is shown. Lots of simulations have been executed in many load conditions. In this paper, the load conditions regarding an electrical vehicle for disabled people is reported. The innovation in this field concerns the integration, in the PEMFC stack mathematical dynamic model, of a synchronous electrical power drive for automotive purposes. Goal of the simulator design has been to create an useful tool which is able to evaluate the behaviour of the whole system so as to optimize the components choose. As regards the simulations with a synchronous electrical power drive, the complete mathematical model allows to evaluate the PEMFC stack performances and electrochemical efficiency. 展开更多
关键词 Proton exchange membrane fuel cells mathematical model automotive synchronous electrical power drive test cycle.
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Collective mechanism of molecular motors and a dynamic mechanical model for sarcomere 被引量:5
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作者 YIN YueHong GUO Zhao 《Science China(Technological Sciences)》 SCIE EI CAS 2011年第8期2130-2137,共8页
A non-equilibrium statistical method is used to study the collective characteristics of myosin II motors in a sarcomere during its contraction. By means of Fokker-Planck equation of molecular motors, we present a dyna... A non-equilibrium statistical method is used to study the collective characteristics of myosin II motors in a sarcomere during its contraction. By means of Fokker-Planck equation of molecular motors, we present a dynamic mechanical model for the sarcomere in skeletal muscle. This model has been solved with a numerical algorithm based on experimental chemical transition rates. The influences of ATP concentration and load on probability density, contraction velocity and maximum active force are discussed respectively. It is shown that contraction velocity and maximum isometric active force increase with the increasing ATP concentration and become constant when the ATP concentration reaches equilibrium saturation. Contraction velocity reduces gradually as the load force increases. We also find that active force begins to increase then decrease with the increasing length of sarcomere, and has a maximum value at the optimal length that all myosin motors can attach to actin filament. Our results are in good agreement with the Hill muscle model. 展开更多
关键词 molecular motor myosin II actin filament SARCOMERE collective characteristics Fokker-Planck equation muscle force model
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