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WNCS在邻区优化中的应用 被引量:1
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作者 蔡凯 肖瑞 曾伟 《移动通信》 2011年第24期18-22,共5页
文章从WCDMA网络邻区优化的重要性和必要性入手,介绍了WNCS这种便捷、高效的邻区优化工具的功能,分五种情况分析了它在WCDMA网络邻区优化中的应用,包括:冗余邻区优化,缺邻区优化,邻区优先级优化,天馈接反问题优化和经纬度错误问题优化。
关键词 wncS 邻区优化 优先级规划
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基于优先级预测器的无线网络化控制系统的动态传输策略
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作者 闫文晓 赵云波 《高技术通讯》 CAS 2023年第12期1286-1294,共9页
本文针对无线通信网络中存在丢包的多包传输无线网络化控制系统(WNCSs),提出了一种基于预测器的动态传输策略,在几乎不增加信道资源占用的情况下显著提升系统稳定性。在多包传输的无线网络化控制系统中,由于通信资源的限制,传感器到控... 本文针对无线通信网络中存在丢包的多包传输无线网络化控制系统(WNCSs),提出了一种基于预测器的动态传输策略,在几乎不增加信道资源占用的情况下显著提升系统稳定性。在多包传输的无线网络化控制系统中,由于通信资源的限制,传感器到控制器间的数据传输中出现丢包问题,影响控制系统性能。针对这个问题,本文首先设计了优先级预测器来预测下一时刻每个传感器数据对系统稳定性的影响,帮助系统决策每个传感器的发送优先级;再通过传输调节器对不同优先级传感器补偿相应的随机退避时间上限,进而让优先级高的传感器在随机退避的方式下优先传输;然后在此策略下设计控制器使系统稳定;最后通过数值仿真验证了本文策略的有效性。 展开更多
关键词 无线网络化控制系统(wncS) 多包传输 丢包 预测器 动态传输策略 指数稳定
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基于动态信道切换的无线网络化控制系统的资源调度策略
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作者 郝小梅 赵云波 《高技术通讯》 CAS 2023年第9期973-980,共8页
本文针对通信网络中存在竞争和非竞争信道的无线网络化控制系统(WNCS),提出了一种基于估计器的信道选择策略,在保证控制系统稳定性的同时尽可能地节约了宝贵的非竞争信道资源。在无线网络化控制系统中,控制信号通过竞争信道传输时可能... 本文针对通信网络中存在竞争和非竞争信道的无线网络化控制系统(WNCS),提出了一种基于估计器的信道选择策略,在保证控制系统稳定性的同时尽可能地节约了宝贵的非竞争信道资源。在无线网络化控制系统中,控制信号通过竞争信道传输时可能发生数据包丢失,导致执行器无法收到实时的控制信号。而传感器端未知控制信号的实际传输情况,因而也无法得知每个时刻执行器所使用的控制信号。针对这种情况,本文首先设计了估计器来估计执行器端上一时刻实际使用的控制信号,再通过信道选择策略来约束执行器端使用控制信号的误差。最后,在所提信道选择策略下设计控制器来保证控制系统稳定。本文通过数值仿真验证了所提算法的有效性。 展开更多
关键词 无线网络化控制系统(wncS) 网络资源 动态信道切换 估计器 控制信号误差
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W_nC^(0,±)(n=1,…,6)团簇结构与电子性质的理论研究 被引量:8
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作者 张秀荣 康张李 李扬 《计算物理》 CSCD 北大核心 2011年第4期598-604,共7页
利用密度泛函理论(DFT)中的杂化密度泛函B3LYP在Lanl2dz基组水平上对WnC0,±(n=1,…,6)团簇的各种可能构型进行几何结构优化,得出它们的基态构型,并对基态构型的稳定性和电子性质进行理论研究.结果表明,当n>3时,稳定构型从平面... 利用密度泛函理论(DFT)中的杂化密度泛函B3LYP在Lanl2dz基组水平上对WnC0,±(n=1,…,6)团簇的各种可能构型进行几何结构优化,得出它们的基态构型,并对基态构型的稳定性和电子性质进行理论研究.结果表明,当n>3时,稳定构型从平面转变成立体结构,同时C原子趋向于表面最稳定;C原子的掺入使得Wn团簇的稳定性增强,其中W3 C团簇稳定性最高,可看作WnC0,±(n=1,…,6)团簇的结构基元;通过比较WnC与纯Wn团簇的垂直亲和能(VEA)和垂直电离能(VIP)可知,WnC团簇更易得到电子,非金属性增强. 展开更多
关键词 wnc0 ±(n=1 6)团簇 几何结构 电子性质 密度泛函理论
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FBIS族:美国政府与决策智囊对外政策的重要信息源 被引量:1
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作者 曾原 《情报探索》 2009年第7期3-5,共3页
梳理了美国FBIS机构及其产品的发展历程,介绍了FBIS族的获取途径及其针对中国进行媒体监测的情况,分析了FBIS族的主要特点,并指出其对我国的启示。
关键词 FBIS wnc OSC 政府决策 公开信息源
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无线网络直流伺服控制系统的研究与仿真
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作者 王健 刘雪花 《现代工业经济和信息化》 2015年第21期80-82,共3页
针对无线网络控制系统存在的无线发射功率与系统稳定性问题,在基于True Time的网络控制系统仿真工具的平台上,对一个典型的直流伺服控制系统模型进行了仿真研究,通过对功率控制策略、网络协议和功率控制参数进行设置,最终使得系统运行... 针对无线网络控制系统存在的无线发射功率与系统稳定性问题,在基于True Time的网络控制系统仿真工具的平台上,对一个典型的直流伺服控制系统模型进行了仿真研究,通过对功率控制策略、网络协议和功率控制参数进行设置,最终使得系统运行在一个稳定的状态。 展开更多
关键词 wncS TRUE TIME 发射功率控制
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环氧氯丙烷改性水性硝化纤维乳液的制备及性能 被引量:7
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作者 蒋吉磊 苏秀霞 +1 位作者 惠媛媛 李仲谨 《中国胶粘剂》 CAS 北大核心 2012年第1期24-27,共4页
以硝化纤维(NC)、异佛尔酮二异氰酸酯(IPDI)和二羟甲基丙酸(DMPA)等为主要原料,制得自乳化型WNC(水性硝化纤维)乳液;然后以环氧氯丙烷(ECH)为交联改性剂,制成改性WNC乳液胶粘剂。研究结果表明:当w(DMPA)=3.5%、w(ECH)=7%时,改性WNC乳液... 以硝化纤维(NC)、异佛尔酮二异氰酸酯(IPDI)和二羟甲基丙酸(DMPA)等为主要原料,制得自乳化型WNC(水性硝化纤维)乳液;然后以环氧氯丙烷(ECH)为交联改性剂,制成改性WNC乳液胶粘剂。研究结果表明:当w(DMPA)=3.5%、w(ECH)=7%时,改性WNC乳液具有优良的储存稳定性,其胶膜耐水性(吸水率为9.1%)、T型剥离强度(7.1 N/mm)、拉伸强度(14.9 MPa)和断裂伸长率(529.3%)俱佳,柔韧性和耐热性优异。 展开更多
关键词 水性硝化纤维 乳液 胶粘剂 环氧氯丙烷 改性
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现代工业生产自动化控制的发展过程 被引量:1
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作者 王治霞 江峡 +1 位作者 赵丽红 方永 《当代化工研究》 2017年第2期92-94,共3页
本文介绍了几种控制系统包括PLC,DCS,FCS, WNCS,Wi NCS,并作了一一对比。
关键词 PLC控制器 PLC控制系统 DCS控制系统 FCS控制系统 wncS控制系统 WiNCS控制系统
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基于TrueTime的无线网络功率控制系统 被引量:3
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作者 赵贤林 逄滨 沈明霞 《计算机工程》 CAS CSCD 北大核心 2010年第10期127-128,132,共3页
介绍一种基于Matlab/Simulink的联合仿真工具——TrueTime工具箱,利用该工具箱,并以直流电机为对象,建立一个无线网络控制系统的仿真模型。通过对路径损耗函数的研究,得出信号传输的最远距离。仿真实验结果表明,在信号传输的最远距离内... 介绍一种基于Matlab/Simulink的联合仿真工具——TrueTime工具箱,利用该工具箱,并以直流电机为对象,建立一个无线网络控制系统的仿真模型。通过对路径损耗函数的研究,得出信号传输的最远距离。仿真实验结果表明,在信号传输的最远距离内,降低节点的发射功率,可实现对无线网络控制系统节点的功率控制。 展开更多
关键词 无线网络控制系统 TRUETIME工具箱 路径损耗 功率控制
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交联型水性硝化纤维乳液的制备及应用研究 被引量:2
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作者 董伟 苏秀霞 张云 《中国胶粘剂》 CAS 北大核心 2014年第9期37-40,共4页
以甘油为交联剂、硝化纤维(NC)为基体和邻苯二甲酸二丁酯(DBP)为增塑剂,制备了交联型水性硝化纤维(WNC)乳液。探讨了Tri-IPDI(异佛尔酮二异氰酸酯三聚体)、甘油及DBP对WNC乳液及其胶膜性能的影响。研究结果表明:当n(Tri-IPDI)∶n(NC)=0... 以甘油为交联剂、硝化纤维(NC)为基体和邻苯二甲酸二丁酯(DBP)为增塑剂,制备了交联型水性硝化纤维(WNC)乳液。探讨了Tri-IPDI(异佛尔酮二异氰酸酯三聚体)、甘油及DBP对WNC乳液及其胶膜性能的影响。研究结果表明:当n(Tri-IPDI)∶n(NC)=0.54∶1.00、w(甘油)=1.0%和w(DBP)=1.5%(均相对于总物料质量而言)时,WNC乳液的储存稳定性良好,WNC胶膜的耐水性和力学性能明显提高,其断裂伸长率由无增塑剂时的85.3%增至356.2%、拉伸强度由1.52 MPa降至1.30 MPa。 展开更多
关键词 水性硝化纤维 乳液 胶粘剂 交联
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Modeling Delay and Packet Drop in Networked Control Systems Using Network Simulator NS2 被引量:9
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作者 Mohammad Shahidul Hasan Christopher Harding Alison Griffiths 《International Journal of Automation and computing》 EI 2005年第2期187-194,共8页
Wireless Networked Control Systems (WNCS) are used to implement a control mechanism over a wireless network that is capable of carrying real-time traffic. This field has drawn enormous attention from current researche... Wireless Networked Control Systems (WNCS) are used to implement a control mechanism over a wireless network that is capable of carrying real-time traffic. This field has drawn enormous attention from current researchers because of its flexibility and robustness. However, designing efficient WNCS over Mobile Ad Hoc Networks (MANET) is still a challenging topic because of its less-predictable aspects, such as inconsistent delay, packet drop probability, and dynamic topology. This paper presents design guidelines for WNCS over MANET using the Network Simulator version 2, NS2 software. It investigates the impact of packet delay and packet drop under the AODV and DSR routing protocols. The simulation results have been compared to MATLAB results for validation. Keywords Adhoc On-Demand Distance Vector (AODV) routing - Dynamic Source routing (DSR) - Mobile Adhoc Networks (MANET) - Wireless Networked Control Systems (WNCS) Mohammad Shahidul Hasan received his BSc and first MSc in Computer Science from the University of Dhaka, Bangladesh. He obtained his 2nd MSc in Computer & Network Engineering from Sheffield Hallam University, Sheffield, UK. Currently he is pursuing his PhD under the Faculty of Computing, Engineering and Technology, Staffordshire University, Stafford, UK in Networked Control Systems over MANET.Chris Harding received his BSc in Computing Science and Masters by Research from Staffordshire University, UK. Currently he is pursuing his PhD in Wireless Networked Control Systems, specifically looking at NCS over MANETs, with research interests in this area concentrating on the network routing and effect of routing protocols on the NCS system.Hongnian Yu is Professor of Computer Science at Staffordshire University. He was a lecturer in Control and Systems Engineering at Yanshan University, China in 1985–1990, did his PhD in Robotics at King’s College London (1990–1994), was a research fellow in Manufacturing Systems at Sussex University (1994–1996), a lecturer in Artificial Intelligence at Liver-pool John Moore’s University (1996–1999), a lecturer in Control and Systems Engineering at the University of Exeter (1999–2002), and a Senior Lecturer in Computing at the University of Bradford (2002–2004). He now leads the Mobile Computing and Distributed Systems Research Group at Staffordshire University. He was a founding member of the Modeling Optimisation Scheduling and Intelligent Control research group at the University of Bradford. He has extensive research experience in neural networks, mobile computing, modeling, control of robot manipulators, and modeling, scheduling, planning, and simulations of large discrete event dynamic systems with applications to manufacturing systems, supply chains, transportation networks, and computer networks. He has published over 100 research papers focusing on the following: neural networks, computer networks, adaptive and robust control of robot manipulators, analysis and control of hybrid machines, control of timed delay systems, predictive control, manufacturing system modeling and scheduling, planning, and supply chains. He has held several research grants from EPSRC, the Royal Society, and the EU, as well as from industry. He was awarded the F.C. William Premium for his paper on adaptive and robust control of robot manipulators by the IEE Council in 1997. Professor Yu is an EPSRC college member, a member of IEEE, and a committee member of several conferences and journal editorial boards.Alison Griffiths has been a Senior Lecturer in Telecommunications at Staffordshire University since 2003. She was a lecturer in Computing at Staffordshire University in 2002–2003. She was a Research Associate on an EPSRC funded project whilst doing her PhD on the convergence of Mobile Computing and Telecommunications at Staffordshire University (1999–2003). The investigation consisted of the communication of different types of media (voice, video conferencing, web browsing, and downloading) over a common network, using a mobile device. Problems considered were the complications that occurred when a user moves, and consequently changes their end-point in the network during communication, with respect to the type of service the user is provided with (delays and losses). She obtained both her MEng and 1st Class BEng (Hons) from Staffordshire University in 1999 and 1998 respectively. She is now part of the Mobile Computing and Distributed Systems Research Group at Staffordshire University. She has published 8 research papers focusing on quality of service and access between cellular and IP packet switched networks. Future directions include mobile agents and control of mobile wireless ad-hoc networks. Her current research interests have extended to Wireless Networked Control Systems, specifically looking at NCS over MANETs, with research interests in this area concentrating on the network routing and effect of routing protocols on the NCS system. 展开更多
关键词 Adhoc On-Demand Distance Vector (AODV) routing Dynamic Source routing (DSR) Mobile Adhoc Networks (MANET) Wireless Networked Control Systems (wncS)
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Feedback Stabilization over Wireless Network Using Adaptive Coded Modulation 被引量:5
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作者 Li Yang Xin-Ping Guan +1 位作者 Cheng-Nian Long Xiao-Yuan Luo 《International Journal of Automation and computing》 EI 2008年第4期381-388,共8页
In this paper,we apply adaptive coded modulation (ACM) schemes to a wireless networked control system (WNCS) to improve the energy efficiency and increase the data rate over a fading channel.To capture the characteris... In this paper,we apply adaptive coded modulation (ACM) schemes to a wireless networked control system (WNCS) to improve the energy efficiency and increase the data rate over a fading channel.To capture the characteristics of varying rate, interference,and routing in wireless transmission channels,the concepts of equivalent delay (ED) and networked condition index (NCI) are introduced.Also,the analytic lower and upper bounds of EDs are obtained.Furthermore,we model the WNCS as a multicontroller switched system (MSS) under consideration of EDs and loss index in the wireless transmission.Sufficient stability condition of the closed-loop WNCS and corresponding dynamic state feedback controllers are derived in terms of linear matrix inequality (LMI). Numerical results show the validity and advantage of our proposed control strategies. 展开更多
关键词 Wireless networked control system (wncS) adaptive coded modulation (ACM) equivalent delay (ED) networked condition index (NCI) multicontroller switched system (MSS) stability.
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无线网络节点功率控制仿真研究 被引量:2
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作者 沈永增 刘锋 《计算机仿真》 CSCD 北大核心 2010年第3期115-118,共4页
在WNCS(无线网络控制系统)仿真中节点的功率控制是仿真关键问题之一。为了研究节点的功率控制问题,基于Truetime工具箱中的Kernel模块和Wireless Network模块,首先,提出了两种功率控制策略,一种是把网络控制中RM(RateMonotonic)调度策... 在WNCS(无线网络控制系统)仿真中节点的功率控制是仿真关键问题之一。为了研究节点的功率控制问题,基于Truetime工具箱中的Kernel模块和Wireless Network模块,首先,提出了两种功率控制策略,一种是把网络控制中RM(RateMonotonic)调度策略的思想应用到节点功率的控制和调度中,而提出的PM(Power Monotonic)功率控制策略,另一种是基于TrueTime仿真示例通过归纳而提出的AH功率控制策略,并着重介绍了PM功率控制策略的算法。最后通过一个无线网络控制系统的仿真模型,就这两种节点功率控制策略对系统性能的影响进行仿真验证。 展开更多
关键词 无线网络控制系统 节点 功率控制 仿真
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Modeling and Control for Wireless Networked Control System 被引量:3
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作者 Chang-Chun Hua Ying Zheng Xin-Ping Guan 《International Journal of Automation and computing》 EI 2011年第3期357-363,共7页
In this paper, the stabilization problem is considered for the class of wireless networked control systems (WNCS). An indicator is introduced in the WNCS model. The packet drop sequences in the indicator are represe... In this paper, the stabilization problem is considered for the class of wireless networked control systems (WNCS). An indicator is introduced in the WNCS model. The packet drop sequences in the indicator are represented as states of a Markov chain. A new discrete Markov switching system model integrating 802.11 protocol and new scheduling approach for wireless networks with control systems are constructed. The variable controller can be obtained easily by solving the linear matrix inequality (LMI) with the use of the Matlab toolbox. Both the known and unknown dropout probabilities are considered. Finally, a simulation is given to show the feasibility of the proposed method. 展开更多
关键词 Wireless networked control systems wncS) packet dropout sequences CONTROLLER network scheduling stability.
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Electronic structure and infrared spectrum of a W_n C^(0,±) (n = 1-6) cluster 被引量:1
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作者 张秀荣 康张李 郭文录 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第10期204-211,共8页
WnC0'± (n= 1-6) clusters are investigated by using the density functional theory (DFT) at the B3LYP/LANL2DZ level. We find that the neutral, anionic and cationic ground state structures are similar within th... WnC0'± (n= 1-6) clusters are investigated by using the density functional theory (DFT) at the B3LYP/LANL2DZ level. We find that the neutral, anionic and cationic ground state structures are similar within the same size, and constituted by substituting a C atom for one W atom in the structures of Wn+1 clusters. The natural bond orbital (NBO) charge analyses indicate that the direction of electron transfer is from the W atom to the 2p orbital of the C atom. In addition, the calculated infrared spectra of the WnC0'± (n= 2-6) clusters manifest that the vibrational frequencies of neutral, anionic and cationic clusters are similar in a range of 80 cm-1-864 cm-1. The high frequency, strong peak modes are found to be an almost stretched deformation of the carbide atom. Finally, the polarizabilities of WnC0'± (n= 1-6) clusters are also discussed. 展开更多
关键词 wnc0'± (n= 1-6) clusters electronic structure infrared spectrum density functionaltheory
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温针灸治疗膝关节骨性关节炎Meta分析 被引量:6
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作者 李小贾 雷梦南 +3 位作者 蒋志明 赵丽娜 胡玲 吴子建 《河南中医》 2021年第2期250-260,共11页
目的:运用循证医学方法对温针灸(needle warming moxibustion,NWM)治疗膝关节骨性关节炎(knee osteoarthritis,KOA)的临床疗效进行系统回顾和Meta分析。方法:检索国内外主要数据库查找相关文献并筛选治疗组为NWM治疗,对照组为传统针刺(t... 目的:运用循证医学方法对温针灸(needle warming moxibustion,NWM)治疗膝关节骨性关节炎(knee osteoarthritis,KOA)的临床疗效进行系统回顾和Meta分析。方法:检索国内外主要数据库查找相关文献并筛选治疗组为NWM治疗,对照组为传统针刺(traditional acupuncture,TA)或电针(electroacupuncture,EA)治疗的相关临床随机对照试验。根据Cochrane偏倚风险评估标准对所纳入文献的质量进行评估,并使用Review Manager 5.3软件对文献数据进行统计分析。结果:共纳入17篇文献,共计1 515例。与EA治疗比较,NWM治疗KOA有效率[OR:0.91,95%CI(0.58,1.43),Z=0.41],WOMAC总评分[WMD:0.98,95%CI(-1.76,3.71),Z=0.70],WOMAC功能活动评分[WMD:2.22,95%CI(-3.94,8.38),Z=0.71],其差异均无统计学意义(P>0.05)。在改善疼痛评分方面[WMD:1.05,95%CI(0.31,1.79),Z=2.77],EA治疗效果优于NWM,两组差异具有统计学意义(P<0.01);在改善僵硬评分方面[WMD:-1.28,95%CI(-2.11,-0.45),Z=3.02],NWM治疗效果优于EA,两组差异具有统计学意义(P<0.01)。与TA治疗比较,NWM治疗KOA有效率[OR:3.44,95%CI(2.25,5.27),Z=5.70],疼痛评分[WMD:-1.61,95%CI(-1.96,-1.27),Z=9.19],Lysholm膝功能评分[WMD:17.36,95%CI(13.40,21.32),Z=8.60],WOMAC总评分[WMD:-10.13,95%CI(-16.19,-4.07),Z=3.28],僵硬评分[WMD:-8.01,95%CI(-13.39,-2.63),Z=2.92],功能活动评分[WMD:-1.14,95%CI(-1.67,-0.61),Z=4.18],ISOA指数[WMD:-2.98,95%CI(-3.78,-2.18),Z=7.26],差异均有统计学意义(P<0.01)。结论:NWM治疗KOA僵硬效果优于EA,治疗KOA有效率、改善WOMAC总评分及改善WOMAC功能活动评分效果与EA相当。NWM治疗KOA有效率、改善WOMAC总评分、疼痛评分、僵硬评分、功能活动评分、Lysholm膝功能评分、ISOA指数效果优于TA。但由于纳入研究在选择性、测量、双盲等其他来源偏倚的存在,可能会在一定程度上影响结果,因此本研究还需要大样本量、高质量的RCTs进行验证。 展开更多
关键词 温针灸 膝关节骨性关节炎 系统回顾 META分析
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基于Wi-Fi的无线网络控制系统的仿真研究 被引量:1
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作者 曾山 翁正新 《微型电脑应用》 2010年第9期10-11,17,共3页
近年来,以Wi-Fi为代表的无线局域网(Wireless Local Area Network,WLAN)技术不断发展和成熟,被广泛应用到各个领域。其中,将无线网络与传统控制系统融合起来,形成具备高移动性、可扩展性和灵活性等优势的无线网络控制系统(Wireless Netw... 近年来,以Wi-Fi为代表的无线局域网(Wireless Local Area Network,WLAN)技术不断发展和成熟,被广泛应用到各个领域。其中,将无线网络与传统控制系统融合起来,形成具备高移动性、可扩展性和灵活性等优势的无线网络控制系统(Wireless Networked Control Systems,WNCS),成为控制界的研究趋势之一。针对基于Wi-Fi技术的无线网络控制系统进行了研究,利用TrueTime仿真工具箱以及MATLAB/Simulink仿真环境,构建了一个WNCS的仿真系统模型,设计了相应的PID控制器,并研究了网络传输速率、采样周期等网络性能指标对系统控制性能的影响。 展开更多
关键词 WI-FI 无线网络控制系统 TRUETIME工具箱 PID控制 网络性能指标
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Analysis and Design of Wireless Networked Control System Utilizing Adaptive Coded ModulationAnalysis and Design of Wireless Networked Control System Utilizing Adaptive Coded Modulation 被引量:4
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作者 YANG Li GUAN Xin-Ping LONG Cheng-Nian LUO Xiao-Yuan 《自动化学报》 EI CSCD 北大核心 2009年第7期911-918,共8页
关键词 无线网络控制系统 计算机技术 自动化系统 网络条件
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