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执行器有时滞的馈能式主动悬架的鲁棒控制 被引量:3
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作者 王鹏 宋鹏云 +1 位作者 张继业 张克跃 《控制理论与应用》 EI CAS CSCD 北大核心 2012年第12期1609-1615,共7页
车辆用的馈能式主动悬架系统具有不确定参数,而且执行器有时滞.为了保证其稳定性、减振性和能量回收性能,我们提出了一种保成本/H∞鲁棒控制器设计方法.对车辆悬架系统性能方面的要求,用二次型加权性能指标和H∞性能指标反映.定义了一个... 车辆用的馈能式主动悬架系统具有不确定参数,而且执行器有时滞.为了保证其稳定性、减振性和能量回收性能,我们提出了一种保成本/H∞鲁棒控制器设计方法.对车辆悬架系统性能方面的要求,用二次型加权性能指标和H∞性能指标反映.定义了一个Lyapunov函数代表这两个性能指标;根据这个Lyapunov函数,把闭环系统设计问题转化为一组线性矩阵不等式以求解控制器.根据直流电机工作原理,分析了参数摄动和执行器时滞对系统能量平衡的影响,推导出了能量平衡方程.最后对二自由度1/4车悬架模型进行了仿真;结果表明:对一定范围内的参数摄动和有界时滞,悬架系统在有效减振的同时,实现了能量的回收. 展开更多
关键词 鲁棒控制 能量回收 执行 保成本 H∞ 线性矩阵不等式
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基于SDL的硬实时调度可执行分析模型 被引量:1
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作者 杨仕平 熊光泽 陈慧 《计算机科学》 CSCD 北大核心 2002年第7期142-145,共4页
1引言 在后PC时代,嵌入式实时系统的需求变得越来越复杂,传统的开发方法已经难于管理及实现日益复杂的实时软件.形式化描述技术FDTs(F0mal Description Techniques)为实时软件代码的自动生成提供了有力的根据,它允许实时软件的仿真、验... 1引言 在后PC时代,嵌入式实时系统的需求变得越来越复杂,传统的开发方法已经难于管理及实现日益复杂的实时软件.形式化描述技术FDTs(F0mal Description Techniques)为实时软件代码的自动生成提供了有力的根据,它允许实时软件的仿真、验证与确认(V&V)及代码的自动生成同步进行. 展开更多
关键词 软件开发 嵌入式实系统 软件代码 SDL 硬实调度可执行分析模型
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建设项目水土保持“三同时”执行率评价体系构建 被引量:1
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作者 宋立旺 王莎 钟壬琳 《中国人口·资源与环境》 CSSCI CSCD 北大核心 2018年第S1期157-159,共3页
为了对建设项目水土保持工作进行比较评价和科学管理,将建设项目水土保持"三同时"的执行情况予以量化是必要的,故提出水土保持"三同时"执行率概念。根据水土保持监管实践,构建了包含设计与变备(变更报批与备案)、... 为了对建设项目水土保持工作进行比较评价和科学管理,将建设项目水土保持"三同时"的执行情况予以量化是必要的,故提出水土保持"三同时"执行率概念。根据水土保持监管实践,构建了包含设计与变备(变更报批与备案)、水土保持监测、表土保护、渣料场防护、整治与恢复、水土保持验收等6个指标的建设项目水土保持"三同时"执行率评价体系。 展开更多
关键词 建设项目 水土保持 “三同执行 评价体系
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时延MPC自主车辆协同控制算法与仿真 被引量:7
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作者 刘富春 贺云 陈奕峰 《计算机工程与应用》 CSCD 北大核心 2019年第23期222-227,共6页
协同自适应巡航控制(CACC)系统中车辆纵向运动的上下位分层控制器结构,上位控制器采用状态空间模型预测控制算法,利用期望距离以及车辆与环境的实时信息决策出被控车辆运动的期望加速度。下位控制器根据期望加速度,求解发动机节气门开... 协同自适应巡航控制(CACC)系统中车辆纵向运动的上下位分层控制器结构,上位控制器采用状态空间模型预测控制算法,利用期望距离以及车辆与环境的实时信息决策出被控车辆运动的期望加速度。下位控制器根据期望加速度,求解发动机节气门开度或制动压力。车辆的执行器时延会对系统的稳定性产生很大的影响。根据动态矩阵控制算法对纯滞后对象的补偿作用,提出一种改进的模型预测控制算法,并与PID控制算法(下位控制器)相结合形成自主车辆纵向运动的上下位分层控制器,以补偿车辆的执行器时延带来的影响。通过SIMULINK/CARSIM联合仿真平台对所设计的算法进行了仿真研究,仿真结果表明所设计算法减小了CACC系统车辆在跟随过程中的速度跟踪误差以及间距误差,提高了系统的稳定性法。 展开更多
关键词 协同自适应巡航控制 执行 模型预测算法 联合仿真
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基于预设性能制导律的欠驱动AUV海底地形鲁棒时滞跟踪控制 被引量:2
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作者 李锦江 向先波 +1 位作者 刘传 杨少龙 《上海交通大学学报》 EI CAS CSCD 北大核心 2022年第7期944-952,共9页
针对自主水下机器人(AUV)面向海底起伏地形跟踪的实际应用需求,设计了基于预设性能制导律的鲁棒时滞跟踪控制器,实现执行机构时滞下的AUV起伏地形跟踪,同时可提升其航行安全性能.首先,基于航行安全性能函数对地形跟踪误差进行转换,结合... 针对自主水下机器人(AUV)面向海底起伏地形跟踪的实际应用需求,设计了基于预设性能制导律的鲁棒时滞跟踪控制器,实现执行机构时滞下的AUV起伏地形跟踪,同时可提升其航行安全性能.首先,基于航行安全性能函数对地形跟踪误差进行转换,结合时变视线制导角在运动学层面设计了预设性能制导律,为AUV动力层提供参考状态输入.其次,为处理执行机构时滞问题并降低精确建模需求,结合径向基函数(RBF)神经网络设计了鲁棒时滞动力学控制器.最后,采用李雅普诺夫理论证明了基于预设性能制导律的鲁棒时滞跟踪控制系统闭环稳定性.仿真结果表明:所设计的控制器可实现AUV起伏地形鲁棒跟踪,且瞬态跟踪误差时刻处于预设性能范围之内,可提升AUV在跟踪海底起伏地形时的航行安全性能. 展开更多
关键词 自主水下机器人 海底地形跟踪 预设性能制导 执行机构 鲁棒控制
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目前政策活动中存在的问题与改进意见
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作者 李洪山 范海燕 刘家顺 《学术交流》 CSSCI 北大核心 1995年第3期85-86,共2页
目前政策活动中存在的问题与改进意见李洪山,范海燕,刘家顺政策是政府管理国家的重要手段之一。建国几十年来,政策对促进、保证我国社会主义建设起了很大作用,但不容否认,我国的政策活动也确实存在着不少的问题。应对如何开展政策... 目前政策活动中存在的问题与改进意见李洪山,范海燕,刘家顺政策是政府管理国家的重要手段之一。建国几十年来,政策对促进、保证我国社会主义建设起了很大作用,但不容否认,我国的政策活动也确实存在着不少的问题。应对如何开展政策活动进行理论与对策研究。一、存在的... 展开更多
关键词 政策执行主体 政策科学 决策程序 政策体系 政策组织 间滞后 东北林业大学 总量控制 政策方案 执行时
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文件解读之三 市人力社保局关于印发天津市工伤职工日常生活及社会适应能力康复管理办法的通知
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《天津社会保险》 2014年第5期56-56,共1页
文件字号:津人社局发〔2014〕77号发文单位:天津市人力资源和社会保障局发文时间:2014年8月27日执行时间:2014年9月1日第一条为进一步做好我市工伤康复工作,探索工伤康复新路径,提高工伤职工日常生活及社会适应能力,根据《市人力社保局... 文件字号:津人社局发〔2014〕77号发文单位:天津市人力资源和社会保障局发文时间:2014年8月27日执行时间:2014年9月1日第一条为进一步做好我市工伤康复工作,探索工伤康复新路径,提高工伤职工日常生活及社会适应能力,根据《市人力社保局关于转发人社部进一步做好工伤康复试点工作指导意见的通知》(津人社局发〔2014〕12号)有关规定,制定本办法。 展开更多
关键词 社会适应能力 工伤职工 工伤康复 人社 发文 工作指导意见 管理办法 人力资源 支付范围 执行时
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试论税收调控的负效应
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作者 文英 《税收与社会》 1997年第11期40-41,共2页
试论税收调控的负效应文英税收调控的负效应是由于调节目标不准确,调节方式运用不当而给社会经济生活带来的不利影响,“两利相权取其重,两害相权取其轻”,通过权衡利害得失,我们应当力图把负效应减少到最低程度。税收调控的负效应... 试论税收调控的负效应文英税收调控的负效应是由于调节目标不准确,调节方式运用不当而给社会经济生活带来的不利影响,“两利相权取其重,两害相权取其轻”,通过权衡利害得失,我们应当力图把负效应减少到最低程度。税收调控的负效应主要有:1.偏调。由于调控目标不配... 展开更多
关键词 税收调控 负效应 公平与效率 税收收入 税收宏观调控 中性原则 供求结构 物质利益 执行时 认识
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Improved Pattern Tree for Incremental Frequent-Pattern Mining 被引量:1
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作者 周明 王太勇 《Transactions of Tianjin University》 EI CAS 2010年第2期129-134,共6页
By analyzing the existing prefix-tree data structure, an improved pattern tree was introduced for processing new transactions. It firstly stored transactions in a lexicographic order tree and then restructured the tre... By analyzing the existing prefix-tree data structure, an improved pattern tree was introduced for processing new transactions. It firstly stored transactions in a lexicographic order tree and then restructured the tree by sorting each path in a frequency-descending order. While updating the improved pattern tree, there was no need to rescan the entire new database or reconstruct a new tree for incremental updating. A test was performed on synthetic dataset T1014D100K with 100 000 transactions and 870 items. Experimental results show that the smaller the minimum sup- port threshold, the faster the improved pattern tree achieves over CanTree for all datasets. As the minimum support threshold increased from 2% to 3.5%, the runtime decreased from 452.71 s to 186.26 s. Meanwhile, the runtime re- quired by CanTree decreased from 1 367.03 s to 432.19 s. When the database was updated, the execution time of im- proved pattern tree consisted of construction of original improved pattern trees and reconstruction of initial tree. The experiment results showed that the runtime was saved by about 15% compared with that of CanTree. As the number of transactions increased, the runtime of improved pattern tree was about 25% shorter than that of FP-tree. The improved pattern tree also required less memory than CanTree. 展开更多
关键词 data mining association rules improved pattern tree incremental mining
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A Stoppable Clock Based Four Step Search Block-Matching Motion Estimation Architecture 被引量:1
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作者 Salah Dhahri Abdelkrim Zitouni Kholdoun Torki 《Computer Technology and Application》 2011年第7期570-574,共5页
Motion Estimation (ME) is considerate one of the most important compression methods. However, ME involves high computational complexity. The main goal is to reduce power conception and the execution time without red... Motion Estimation (ME) is considerate one of the most important compression methods. However, ME involves high computational complexity. The main goal is to reduce power conception and the execution time without reducing image quality. In this paper, the authors have proposed high parallel processing architecture is presented for four-step search block-matching motion estimation. The proposed method is based on the stoppable clock models. The architecture has been simulated and synthesized with VHDL and ASIC (CMOS 45 nm). Synthesize results show that the proposed architecture reduces the power consumption and achieves a high performance for real time motion estimation. 展开更多
关键词 H264 four step search power consumption motion estimation.
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Task scheduling scheme by checkpoint sharing and task duplication in P2P-based desktop grids
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作者 Joon-Min Gil Young-Sik Jeong 《Journal of Central South University》 SCIE EI CAS 2014年第10期3864-3872,共9页
A scheduling scheme is proposed to reduce execution time by means of both checkpoint sharing and task duplication under a peer-to-peer(P2P) architecture. In the scheme, the checkpoint executed by each peer(i.e., a res... A scheduling scheme is proposed to reduce execution time by means of both checkpoint sharing and task duplication under a peer-to-peer(P2P) architecture. In the scheme, the checkpoint executed by each peer(i.e., a resource) is used as an intermediate result and executed in other peers via its duplication and transmission. As the checkpoint is close to a final result, the reduction of execution time for each task becomes higher, leading to reducing turnaround time. To evaluate the performance of our scheduling scheme in terms of transmission cost and execution time, an analytical model with an embedded Markov chain is presented. We also conduct simulations with a failure rate of tasks and compare the performance of our scheduling scheme with that of the existing scheme based on client-server architecture. Performance results show that our scheduling scheme is superior to the existing scheme with respect to the reduction of execution time and turnaround time. 展开更多
关键词 P2P-based desktop grids checkpoint sharing task duplication embedded Markov chain
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A Strategy of Density-Based Partitioning for Scalability Problem in Network Self-management
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作者 Romildo Martins da Silva Bezerra Joberto Sergio Barbosa Martins 《Computer Technology and Application》 2013年第8期437-443,共7页
A density-based partitioning strategy is proposed for large domain networks in order to deal with the scalability issue found in autonomic networks considering, as a scenario, the autonomic Quality of Service (QoS) ... A density-based partitioning strategy is proposed for large domain networks in order to deal with the scalability issue found in autonomic networks considering, as a scenario, the autonomic Quality of Service (QoS) management context. The approach adopted focus as on obtaining dense network partitions having more paths for a given vertices set in the domain. It is demonstrated that dense partitions improve autonomic processing scalability, for instance, reducing routing process complexity. The solution looks for a significant trade-off between partition autonomic algorithm execution time and path selection quality in large domains. Simulation scenarios for path selection execution time are presented and discussed. Authors argue that autonomic networks may benefit from the dense partition approach proposed by achieving scalable, efficient and near real-time support for autonomic management systems. 展开更多
关键词 Network management SELF-MANAGEMENT scalability.
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High Efficiency Predictive Control Strategy Applied to a Fower Factor Correction System
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作者 Fernando Parillo 《Journal of Energy and Power Engineering》 2012年第11期1809-1815,共7页
This work explores the feasibility of a novel predictive control strategy on a power factor correction system. The proposed control strategy allows a significant reduction of the power losses respect to a classical pr... This work explores the feasibility of a novel predictive control strategy on a power factor correction system. The proposed control strategy allows a significant reduction of the power losses respect to a classical predictive control strategy working with a fixed execution time Ts. The proposed control strategy operates with a variable execution time T~, and it has been implemented using a low cost hardware platform based on TI~ TMS320F2812 DSP. The chosen platform is capable to execute a control strategy code with a variable execution time T,. This operation can be performed by setting in proper manner, the timer registers of one of two event manager A/B blocks present on the mentioned DSP (digital signal processor). 展开更多
关键词 DSP event manager A/B PFC variable execution time T system efficiency.
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Miniature Actuators and Scaling Effect
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作者 Tatiana Kelemenova Michal Kelemen 《Journal of Mechanics Engineering and Automation》 2013年第6期393-396,共4页
The paper deals with miniature actuators and scaling effect, which occurs in using of these actuators. Scaling effect describes how much decreased performance in miniaturized actuator is. Scaling effect law helps to m... The paper deals with miniature actuators and scaling effect, which occurs in using of these actuators. Scaling effect describes how much decreased performance in miniaturized actuator is. Scaling effect law helps to make perfect decision for right type of actuator. This analysis should be as the first strategic step for actuator selection. Research in area of in-pipe machine shows that scaling effect in both used actuator types (electromagnetic and piezoelectric) is the same. Passive forces cannot be neglected, because of their values, which are comparable with active forces in system. There is a potential risk, that designed system will have bigger passive forces than active forces and system cannot fulfill requirements. Energy sources selection has also important role in system design with respecting the energy requirements of selected actuator. Consequently, energy balance is also important viewpoint for actuator selection. 展开更多
关键词 ACTUATOR MECHATRONICS scale effect.
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Pakistan Electronic Media Legal and Regulatory System
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作者 Muhammad Abrar 《Journalism and Mass Communication》 2014年第1期36-41,共6页
In this paper, the legal and regulatory system of Pakistan media TV will be examined. In the digital era, electronic TV media has become one of Pakistan's fastest growing service industries, but there is still a need... In this paper, the legal and regulatory system of Pakistan media TV will be examined. In the digital era, electronic TV media has become one of Pakistan's fastest growing service industries, but there is still a need for considerable improvement with regard to the laws and regulations governing the activity. It defines the Pakistan electronic regulatory process and the relevant media laws. After that, it discusses enforcement mechanism operating in Pakistan, Lastly, it suggests some recommendations. 展开更多
关键词 MEDIA REGULATION ENFORCEMENT BROADCASTING Pakistan TELEVISION
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Settling Time Design and Parameter Tuning Methods for Finite-Time P-PI Control 被引量:1
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作者 Keigo Hiruma Hisakazu Nakamura Yasuyuki Satoh 《Journal of Control Science and Engineering》 2016年第1期1-10,共10页
High precision position control and high speed control of the robot manipulators are fundamental and important control problems. The effectiveness of finite-time P-PI control was confirmed by end-effector position con... High precision position control and high speed control of the robot manipulators are fundamental and important control problems. The effectiveness of finite-time P-PI control was confirmed by end-effector position control of robot manipulators. However, parameter tuning method has not been proposed to finite-time P-PI control. In this paper, we propose a settling time design method and a parameter tuning method for the finite-time P-PI control. The effectiveness of the proposed parameter tuning method is confirmed by experiments of end-effcctor position control of a robot manipulator. 展开更多
关键词 Nonlinear control finite-time control P-PI control settling time design robot manipulator.
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车载信息系统在院外急救中的应用 被引量:1
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作者 张振新 林长春 +1 位作者 吴隽 涂建刚 《中国急救复苏与灾害医学杂志》 2007年第5期296-297,共2页
无锡市急救中心自2002年使用车载信息系统已5年。2007年1月8日起又启用了新一代车载信息系统,并结合我中心工作需求,进行了功能扩展,有利于院外急救工作。1车载信息系统提供的功能1.1人员上下班管理通过在救护车车载信息终端输入急救人... 无锡市急救中心自2002年使用车载信息系统已5年。2007年1月8日起又启用了新一代车载信息系统,并结合我中心工作需求,进行了功能扩展,有利于院外急救工作。1车载信息系统提供的功能1.1人员上下班管理通过在救护车车载信息终端输入急救人员工号的方式选择“上班”或“下班”,管理人员和调度人员通过管理系统能随时掌握人员上下班信息。 展开更多
关键词 1.2接收/查看、显示有关信息可接收/查看并显示有关命令、通知单 执行命令的救护车状态信息、上传定位信息、收费信息、导航、电话(与病家或调度中心联系)等功能1.3专家知识库查询功能集成了毒品、化学危险品、救治措施数据库 设置了无锡市急救中心规章制度和无锡市各家医院专家资料信息 方便车上人员随查询专家知识库能根据需要不断更新2车载信息系统在急救中的作用2.1便于调度人员指挥和调度车载信息系统是急救调度系统的一个子系统
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自主车队的非线性建模与控制 被引量:5
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作者 岳伟 郭戈 《控制与决策》 EI CSCD 北大核心 2009年第7期996-1000,1006,共6页
针对自主式车队建模与控制这一重要课题,建立了包含路面坡度和风力因素的非线性车辆动力学模型,进而基于反馈线性化方法提出一种对坡度和风速变化具有一定适应能力的非线性PID控制算法,并给出了一种可以克服燃油和传输延时的控制器设计... 针对自主式车队建模与控制这一重要课题,建立了包含路面坡度和风力因素的非线性车辆动力学模型,进而基于反馈线性化方法提出一种对坡度和风速变化具有一定适应能力的非线性PID控制算法,并给出了一种可以克服燃油和传输延时的控制器设计方法以及可允许的延时上限.所得的非线性模型在很大程度上完善了现有的车辆动力学模型.仿真实验表明,该控制方法不但可实现车队的稳定运行控制,而且使车队控制效果大大改善. 展开更多
关键词 非线性模型 反馈线性化 非线性PID 执行器延
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PARALLEL SIMULTANEOUS STABILIZATION OF A SET OF PORT-CONTROLLED HAMILTONIAN SYSTEMS SUBJECT TO ACTUATOR SATURATION 被引量:4
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作者 Airong WEI Yuzhen WANG Xiaoming HU 《Journal of Systems Science & Complexity》 SCIE EI CSCD 2011年第1期120-139,共20页
This paper investigates parallel simultaneous stabilization (PSS) of a set of multi-input nonlinear Port-Controlled Hamiltonian (PCH) systems subject to actuator saturation (AS), and proposes a number of results... This paper investigates parallel simultaneous stabilization (PSS) of a set of multi-input nonlinear Port-Controlled Hamiltonian (PCH) systems subject to actuator saturation (AS), and proposes a number of results on the design of PSS controllers for the PCH systems with AS. Firstly, the case of two PCH systems with AS is studied. Exploring the special property of the saturation nonlinearity and the structural properties of dissipative Hamiltonian system, the two systems are combined to generate an augmented PCH system, with which some results on the control design are then obtained. When there are external disturbances in the two systems, a robust PSS controller is designed for the systems. Secondly, the case of more than two PCH systems with AS is investigated, and several new results are proposed for the PSS problem. Finally, two illustrative examples are presented to show that the stabilization controllers obtained in this paper work very well. 展开更多
关键词 Actuator saturation PCH system robust parallel simultaneous stabilization
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浅谈对环境工程监理的认识 被引量:4
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作者 杜海声 《环境工程》 CAS CSCD 北大核心 2009年第S1期543-546,共4页
通过对环境工程监理的作用和重点内容的分析,明确了环境工程监理在建设项目"三同时"执行情况的监管方面和实现污染治理设施长期稳定运行方面的较大作用,提出了环境工程监理应推行的范围和对环境工程监理队伍的要求,并对环境... 通过对环境工程监理的作用和重点内容的分析,明确了环境工程监理在建设项目"三同时"执行情况的监管方面和实现污染治理设施长期稳定运行方面的较大作用,提出了环境工程监理应推行的范围和对环境工程监理队伍的要求,并对环境工程监理工作的开展提出了建议。 展开更多
关键词 环境工程监理 “三同执行 污染治理设施 长期稳定运行 建议
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