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A 3D Geometry-Based Scattering Model for Vehicleto-Vehicle Wideband MIMO Relay-Based Cooperative Channels 被引量:1
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作者 Xiaolin Liang Xiongwen Zhao +2 位作者 Shu Li Qi Wang Wenbing Lu 《China Communications》 SCIE CSCD 2016年第10期1-10,共10页
In this paper, a three-dimensional(3D) geometry- based stochastic scattering model(GBSSM) for wideband multi-input multi-output(MIMO) vehicle-to-vehicle(V2V) relay-based cooperative fading channel based on geometrical... In this paper, a three-dimensional(3D) geometry- based stochastic scattering model(GBSSM) for wideband multi-input multi-output(MIMO) vehicle-to-vehicle(V2V) relay-based cooperative fading channel based on geometrical three-cylinder is proposed. Non-line-of-sight(NLOS) propagation condition is assumed in amplify-and-forward(AF) cooperative networks from the source mobile station(S) to the destination mobile station(D) via the mobile relay station(R). We extend the proposed narrowband model to wideband and also introduce the carrier frequency and bandwidth into the model. To avoid complicated procedure in deriving the analytical expressions of the channel parameters and functions, the channel is realized first. By using the realized channel matrix, the channel properties are further investigated. 展开更多
关键词 geometry-based scattering model MIMO relay-based cooperative communication vehicle-to-vehicle(V2V) WIDEBAND
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Quantum decoder design for subsystem surface code based on multi-head graph attention and edge weighting
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作者 Nai-Hua Ji Hui-Qian Sun +2 位作者 Bo Xiao Ping-Li Song Hong-Yang Ma 《Chinese Physics B》 2025年第2期165-176,共12页
Quantum error-correcting codes are essential for fault-tolerant quantum computing,as they effectively detect and correct noise-induced errors by distributing information across multiple physical qubits.The subsystem s... Quantum error-correcting codes are essential for fault-tolerant quantum computing,as they effectively detect and correct noise-induced errors by distributing information across multiple physical qubits.The subsystem surface code with three-qubit check operators demonstrates significant application potential due to its simplified measurement operations and low logical error rates.However,the existing minimum-weight perfect matching(MWPM)algorithm exhibits high computational complexity and lacks flexibility in large-scale systems.Therefore,this paper proposes a decoder based on a graph attention network(GAT),representing error syndromes as undirected graphs with edge weights,and employing a multihead attention mechanism to efficiently aggregate node features and enable parallel computation.Compared to MWPM,the GAT decoder exhibits linear growth in computational complexity,adapts to different quantum code structures,and demonstrates stronger robustness under high physical error rates.The experimental results demonstrate that the proposed decoder achieves an overall accuracy of 89.95%under various small code lattice sizes(L=2,3,4,5),with the logical error rate threshold increasing to 0.0078,representing an improvement of approximately 13.04%compared to the MWPM decoder.This result significantly outperforms traditional methods,showcasing superior performance under small code lattice sizes and providing a more efficient decoding solution for large-scale quantum error correction. 展开更多
关键词 quantum error correction graph attention network subsystem surface code circuit-level noise
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Application of soft sensor modeling based on SSA-CNN-LSTM in solar thermal power collection subsystem
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作者 LU Xiaojuan ZHANG Yaohui +2 位作者 FAN Duojin KONG Linggang ZHANG Zhiyong 《Journal of Measurement Science and Instrumentation》 2025年第4期505-514,共10页
To address the stochasticity and nonlinearity of solar collector power systems,a soft sensor prediction model with a hybrid convolutional neural network(CNN)and long short-term memory network(LSTM)was constructed,and ... To address the stochasticity and nonlinearity of solar collector power systems,a soft sensor prediction model with a hybrid convolutional neural network(CNN)and long short-term memory network(LSTM)was constructed,and the hyperparameter optimization of the hybrid neural network(CNN-LSTM)was carried out by using the sparrow search algorithm(SSA).The model utilized the powerful feature extraction and non-linear mapping capabilities of deep learning to effectively handle the complex relationship between input and target variables.The batch normalization technique was used to speed up the training and improve the stability of the soft-sensing model,and the random discard technique was used to prevent the soft-sensing model from overfitting.Finally,the mean absolute error(MAE)was used to assess the accuracy of the soft sensor model predictions.This study compared the proposed model with soft sensor prediction models like Bp,Elman,CNN,LSTM,and CNN-LSTM,using dynamic thermal performance data from the solar collector field of the molten salt linear Fresnel photovoltaic demonstration power plant.The deep learning-based soft sensor model outperformed the other models according to the experimental data.Its coefficients of determination(namely R^(2))are higher by 6.35%,8.42%,5.69%,6.90%,and 3.67%,respectively.The accuracy and robustness have been significantly improved. 展开更多
关键词 soft sensor modeling linear Fresnel collector subsystem collector field outlet temperature deep learning sparrow search algorithm
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具有不可镇定子系统的切换系统的事件驱动控制
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作者 冯肖亮 施圣洋 闫晶晶 《控制工程》 北大核心 2026年第1期14-21,共8页
研究了事件驱动传输机制和执行器饱和影响下,具有不可镇定子系统的切换系统的指数稳定性。首先,通过设计适当的事件驱动传输机制和预设命题,实现了执行器饱和约束下闭环切换系统的模态转换;然后,针对两种情况求李雅普诺夫函数的递增/递... 研究了事件驱动传输机制和执行器饱和影响下,具有不可镇定子系统的切换系统的指数稳定性。首先,通过设计适当的事件驱动传输机制和预设命题,实现了执行器饱和约束下闭环切换系统的模态转换;然后,针对两种情况求李雅普诺夫函数的递增/递减率,从而得到保证闭环切换系统指数稳定的充分性条件,并验证了预设命题的合理性;最后,基于线性矩阵不等式方法给出了反馈矩阵的设计方法。仿真结果验证了理论分析的正确性。 展开更多
关键词 切换系统 不可镇定子系统 事件驱动 执行器饱和
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继电器类单机长期热待机加速退化试验方法与系统
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作者 何涛 郑伟 +4 位作者 郭士豪 陈绘宇 林义刚 舒亮 陈威 《机电工程技术》 2026年第3期108-117,共10页
针对继电器类单机在长期热待机工况下的可靠性评估需求,提出了一套基于加速退化试验的工程化验证方法,并研制了配套自动化测试系统。通过解析单机热待机任务剖面的温度与电应力特征及影响机理,确立了温度-电应力联合加载加速试验模式,... 针对继电器类单机在长期热待机工况下的可靠性评估需求,提出了一套基于加速退化试验的工程化验证方法,并研制了配套自动化测试系统。通过解析单机热待机任务剖面的温度与电应力特征及影响机理,确立了温度-电应力联合加载加速试验模式,制定了多应力协同加载方案。自主开发的测试系统配备高精度数据采集模块与动态间隔测试策略,实现了5台试件关键性能参数的连续监测。试验数据显示,在90℃加速温度条件下,单机退化过程显著激活,其退化趋势与数字样机模型预测结果的吻合度达到95%。研究成果不仅建立了从应力加载到数据采集的全流程试验框架,更通过退化数据与理论模型的交互验证,形成了可量化的评估体系,为继电器类单机长寿命可靠性评估提供了标准化解决方案,具有重要的工程应用价值。 展开更多
关键词 继电器类单机 热待机 加速退化试验 测试系统
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小扰动强度视角下新型电力系统构建的必要约束条件探讨
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作者 胡光 辛焕海 +3 位作者 庄可好 高晖胜 黄林彬 鞠平 《中国电机工程学报》 北大核心 2026年第1期17-30,I0002,共15页
大规模电力电子设备的接入使得新型电力系统动态特性非常复杂,系统的安全稳定运行面临挑战。小扰动动态特性良好是系统安全稳定运行的基本前提,该文从系统小扰动强度视角,探讨新型电力系统安全稳定运行的必要条件,给出电压幅值、相角和... 大规模电力电子设备的接入使得新型电力系统动态特性非常复杂,系统的安全稳定运行面临挑战。小扰动动态特性良好是系统安全稳定运行的基本前提,该文从系统小扰动强度视角,探讨新型电力系统安全稳定运行的必要条件,给出电压幅值、相角和频率3个维度的强度约束。首先,基于特征子空间的降阶方法,由原系统复杂模型导出描述系统电压幅值、相角与频率动态特性的低阶特征子系统,用于反映原系统3个维度的关键动态特性;其次,基于特征子系统,建立包含电压广义短路比、相角广义短路比和频率动态偏移的新型电力系统强度指标,并通过3个不等式明确系统构建的必要强度约束条件,分别对应电压强度、相角(同步)强度和频率强度;最后,仿真验证该所提系统动态分析方法体系及强度约束条件的有效性。 展开更多
关键词 特征子系统 广义短路比 强度约束 全局模态
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系统强度视角下含跟网型和构网型设备混联系统的低频段小干扰稳定分析
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作者 詹修瑜 袁辉 +1 位作者 胡光 辛焕海 《电工技术学报》 北大核心 2026年第3期865-882,共18页
未来电力系统将呈现大量跟网型与构网型设备混联并网新特征。然而,强电网背景下系统存在构网型设备引发的低频振荡问题,构网型设备异构特性以及跟网型与构网型设备交互作用如何影响该类低频振荡问题目前尚不清楚。为此,该文首先构建了... 未来电力系统将呈现大量跟网型与构网型设备混联并网新特征。然而,强电网背景下系统存在构网型设备引发的低频振荡问题,构网型设备异构特性以及跟网型与构网型设备交互作用如何影响该类低频振荡问题目前尚不清楚。为此,该文首先构建了适用于低频振荡分析的构网型和跟网型设备的简化模型;其次,基于矩阵摄动理论,分别针对考虑异构特性的构网型设备多馈入系统以及跟网型和构网型混联多馈入系统,构造了近似反映原系统低频主导模态的等效同构系统,保留了原系统网架结构特征,并得到了能反映原系统低频主导模态的特征子系统;然后,从系统强度的视角提出了考虑异构特性的系统低频段稳定性评估指标,并揭示了构网型设备异构特性以及跟网型设备动态对系统低频段稳定性的作用机理;最后,通过仿真算例说明了所提分析方法的有效性。 展开更多
关键词 跟网型设备 构网型设备 低频振荡 特征子系统 系统强度
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机组组合模型不可行分析方法综述与展望
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作者 刘彦宏 虞泽宽 +3 位作者 颜心斐 黄河 钟海旺 康重庆 《电网技术》 北大核心 2026年第1期122-134,I0074-I0077,共17页
机组组合是电力系统优化调度和电力市场出清的关键环节。随着我国电力市场运营范围的扩大与市场参与者的多元化,在电力市场出清时效性要求下,复杂出清模型不收敛或出清结果不合理的情况时有发生。当前电力市场出清模型的可行性修复主要... 机组组合是电力系统优化调度和电力市场出清的关键环节。随着我国电力市场运营范围的扩大与市场参与者的多元化,在电力市场出清时效性要求下,复杂出清模型不收敛或出清结果不合理的情况时有发生。当前电力市场出清模型的可行性修复主要依赖人工经验修改模型与调整边界条件,尚缺少通用的模型不可行分析与修复方法,这将影响电力市场的公平运营与电力系统的安全经济运行。文章梳理了不同求解框架下的机组组合模型不可行分析方法,在此基础上总结了混合整数线性规划通用的不可行分析方法,并展望了在机组组合模型不可行分析与修复方面有待进一步研究的内容,希望为我国新型电力系统建设及电力市场运营工作提供有益参考。 展开更多
关键词 机组组合 拉格朗日松弛 混合整数线性规划 不可行分析 最小不可行子系统
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基于部分状态反馈信息的切换控制器设计
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作者 付雯雯 周宇生 《井冈山大学学报(自然科学版)》 2026年第1期1-9,共9页
系统状态信息不能得到完全的反馈与使用是实际控制系统中普遍存在的问题。采用切换思想可以很好地解决由于部分状态反馈信息量不足和控制输入能量受限所导致受控系统难以镇定的难题。为此,本研究提出将部分状态反馈与切换控制思想相结... 系统状态信息不能得到完全的反馈与使用是实际控制系统中普遍存在的问题。采用切换思想可以很好地解决由于部分状态反馈信息量不足和控制输入能量受限所导致受控系统难以镇定的难题。为此,本研究提出将部分状态反馈与切换控制思想相结合的策略。针对二阶线性受控系统,为受控系统设计两个带参数的部分状态反馈控制器,然后基于能量落差最大的原则计算出切换直线,从而设计合适的切换规则及切换控制器。针对三阶线性受控系统,利用Pade降阶方法将其转化为线性二阶系统后,对简化模型设计合适的切换控制器,再基于投影矩阵方法得到原三阶线性受控系统的切换控制器。仿真结果表明,采用本研究的切换控制策略能够使得受控系统的状态快速收敛到平衡点。 展开更多
关键词 切换控制 部分状态反馈 不稳定子系统 渐近稳定
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Design on the Soccer-robot Wireless Communication Subsystem
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作者 李鹏 《中国新通信》 2009年第15期91-93,共3页
在足球机器人比赛中,无线通信子系统的主要任务是将主机的命令准确地传送给每一个机器人,其性能的好坏,将会影响足球机器人的运动和比赛的顺利进行,直接关系到比赛的胜负。本文提出了一种基于高速尢线通信模块PTR6000的设计方案,... 在足球机器人比赛中,无线通信子系统的主要任务是将主机的命令准确地传送给每一个机器人,其性能的好坏,将会影响足球机器人的运动和比赛的顺利进行,直接关系到比赛的胜负。本文提出了一种基于高速尢线通信模块PTR6000的设计方案,介绍了发射和接收部分的硬件及软件设计,有效地提高了通信系统的性能,为足球机器人系统提供了一个高效可靠的通信平台。 展开更多
关键词 足球机器人 无线通信子系统 PTR6000 人工智能
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DVOR地面设备控制交换子系统设计
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作者 苏从兵 王岸石 +1 位作者 刘新宇 许健 《现代导航》 2026年第1期27-32,共6页
多普勒甚高频全向信标(DVOR)是民航导航系统中的重要组成部分,其控制交换子系统性能直接影响导航信号的稳定输出。围绕DVOR地面设备控制交换子系统需求,提出了一种由主备冗余的控制接口单元构成的系统架构。阐述了面向系统需求的整体设... 多普勒甚高频全向信标(DVOR)是民航导航系统中的重要组成部分,其控制交换子系统性能直接影响导航信号的稳定输出。围绕DVOR地面设备控制交换子系统需求,提出了一种由主备冗余的控制接口单元构成的系统架构。阐述了面向系统需求的整体设计思路,介绍了控制接口单元的设计与实现方法;重点分析了双控制接口单元的主从协同机制,包括数据同步策略与主从状态协调逻辑,并对告警触发自动关机的后续自恢复开机功能流程进行了设计说明。该设计为DVOR地面设备控制交换子系统工程实现提供了可行的技术路径。 展开更多
关键词 多普勒甚高频全向信标 控制交换子系统 控制接口单元
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5G增强通话DCSF建设方案研究
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作者 张玉珍 《通信电源技术》 2026年第1期159-161,共3页
电信运营商拥有大规模的语音用户数,但是随着OTT(Over The Top)业务的广泛使用,给运营商基础语音业务受到了冲击,每用户通话时长(Minutes Of Usage,MOU)持续降低且收入逐年下降。5G增强通话是基于5G的新一代通话产品,提供超高清、智能... 电信运营商拥有大规模的语音用户数,但是随着OTT(Over The Top)业务的广泛使用,给运营商基础语音业务受到了冲击,每用户通话时长(Minutes Of Usage,MOU)持续降低且收入逐年下降。5G增强通话是基于5G的新一代通话产品,提供超高清、智能化、全交互三大能力,以期增加用户黏性并为基础通话业务带来新的潜在增长空间。介绍5G增强通话的业务类型和发展现状,然后从建设原则、网络架构、数据通道信令功能(Data Channel Signaling Function,DCSF)网元建设方案、资源池建设方案、网络安全及可靠性等方面探讨5G增强通话控制面网元DCSF的建设实施方案。 展开更多
关键词 5G增强通话 数据通道信令功能(DCSF) 媒体功能(MF) IP多媒体子系统(IMS)
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Canonical Correlation Analysis on Natural Subsystem and Economic Subsystem——Taking the Eco-development of Hebei Province as an Example
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作者 赵晓晓 张雯 马寨璞 《Agricultural Science & Technology》 CAS 2012年第8期1722-1726,1775,共6页
[Objective] This study aimed to provide referential basis for ecosystem study of Hebei Province in the new decade of 21st century, by investigating the correlation between natural subsystem and economic subsystem. [Me... [Objective] This study aimed to provide referential basis for ecosystem study of Hebei Province in the new decade of 21st century, by investigating the correlation between natural subsystem and economic subsystem. [Method] The correlation between natural subsystem and economic subsystem in ecosystem was discussed by means of the canonical correlation, and the correlation between variables was explored with statistical data. [Result] The canonical correlation between the two subsystems could be explained by three groups of typical variables, Le., the canonical correlation between crop production and consumption; the canonical correlation between agricultural crop production, aquaculture and scientific research development funds; and the canonical correlation between forest area and GDP per capita. With the growth of economy and revenue and the steady development of agricultural production, there are still some serious problems, including the change of residents consumption is out of proportion to its material consumption; the socio-economic development depends on consuming of forests more heavily, which destroy the balance between the economic growth and environmental protection. [Conclusion] The results provide referential basis for the ecosystem study of Hebei Province. 展开更多
关键词 Canonical correlation Economic subsystem Natural subsystem Urban ecology
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Useful life prediction using a stochastic hybrid automata model for an ACS multi-gyro subsystem 被引量:2
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作者 CHENG Yuehua JIANG Liang +1 位作者 JIANG Bin LU Ningyun 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2019年第1期154-166,共13页
A useful life prediction method based on the integration of the stochastic hybrid automata(SHA) model and the frame of the dynamic fault tree(DFT) is proposed. The SHA model can incorporate the orbit environment, work... A useful life prediction method based on the integration of the stochastic hybrid automata(SHA) model and the frame of the dynamic fault tree(DFT) is proposed. The SHA model can incorporate the orbit environment, work modes, system configuration, dynamic probabilities and degeneration of components,as well as spacecraft dynamics and kinematics. By introducing the frame of DFT, the system is classified into several layers, and the problem of state combination explosion is artfully overcome.An improved dynamic reliability model(DRM) based on the Nelson hypothesis is investigated to improve the defect of cumulative failure probability(CFP), which is used to address the failure probability of components in the SHA model. The simulation using the Monte-Carlo method is finally conducted on two satellites, which are deployed with the same multi-gyro subsystem but run on different orbits. The results show that the predicted useful life of the attitude control system(ACS) with consideration of abrupt failure,degradation, and running environment is quite different between the two satellites. 展开更多
关键词 useful life prediction STOCHASTIC hybrid AUTOMATA (SHA) multi-gyro subsystem DYNAMIC fault tree (DFT) DYNAMIC reliability.
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Kinematics Analysis of Motion Simulation Subsystem for Unmanned Vehicle 被引量:1
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作者 TANG Guoming MEI Tao +1 位作者 LIU Wei LI Bichun 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2011年第6期923-934,共12页
Unmanned vehicle has attracted wide attention and interests throughout the world since it first deputed in the 1960s. However, the experimental methods for unmanned vehicle's intelligent behavior, such as semi-physic... Unmanned vehicle has attracted wide attention and interests throughout the world since it first deputed in the 1960s. However, the experimental methods for unmanned vehicle's intelligent behavior, such as semi-physical simulation and motion subsystem, have not been widely explored. First, the requirements of the motion subsystem in unmanned vehicle semi-physical facility are analyzed, and a six DOF parallel manipulator is selected to reproduce the pose of the vehicle. The link lengths of the motion subsystem are worked out under the given rotational angles of the vehicle. According to the geometric properties of tetrahedron, three joint positions of the top platform are determined, and the rest are obtained from the first three position vectors. Six constraint equations are set up based on the vertices on the top platform and the link lengths. In order to solve the six angle variables, a numerical algorithm built on the Newton-Raphson iterative method is presented, which is based on Taylor series expansion of six constraint equations. The pose of the top platform is ultimately calculated. The eigenvalues of the top platform are solved to obtain the natural frequencies of the motion subsystem. The coordinates of six joint centers on the top platform and six constraint equations can be realized by simple algebraic manipulation, which allows significant abbreviation in the formulation and provides a systematic way of obtaining the kinematic solution of the parallel manipulator. A numerical example is given and its efficacy is demonstrated by the inverse kinematics. The computation strategy based on tetrahedron method and Newton-Raphson iterative method provide a simple and cost-effective method for solving forward kinematics of six DOF parallel manipulators, and this method sheds light on other parallel manipulators. 展开更多
关键词 unmanned vehicle motion simulation subsystem Tetrahedron method KINEMATICS Newton-Raphson iterative method
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The Design of I/O Subsystem in Satellite Real-Time Microkernel Operating System 被引量:1
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作者 Liu Xiaodong & Li Lianzhi (Dept. of Computer Science & Engineering, Harbin Institute of Technology, 150001, P. R. China) Qian Chunlai(Beijiing Institute of Radio Measurement, 100854, P. R. China) 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 1998年第3期77-81,共5页
One of the most important features of modern minor satellites is to realize autonomous moving. The performance of the satellite autonomous computer operating system acting as the control center is utmost important. Th... One of the most important features of modern minor satellites is to realize autonomous moving. The performance of the satellite autonomous computer operating system acting as the control center is utmost important. The recent trend in operating system development is adopting microkernel architecture which holds such advantages as microminiaturization, modularity, portability and extendibility. The performance of I/O subsystem is currently receiving considerable research attention. Object-orientation offers an approach to application development in which software system can be constructed by composing and refining the pre-designed plug-compatible software components.It also starts with some basic notions fairly well accepted in computer science, namely encapsulation and reuse. In this paper, a new object-oriented real-time I/O subsystem model has been designed.In this model, the traditional I/O subsystem framework is discarded and a stream mechanism based on the object-oriented concept is introduced. In addition, the I/O requests are classified according to their time emergency to obtain real-time performance. So, this model meets such satelliteperformance requirements as reliability, flexibility, portability and real-time performance. 展开更多
关键词 Satellite operating system I/O subsystem OBJECT-ORIENTED REAL-TIME
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Comparative study on multibody vehicle dynamics models based on subsystem synthesis method using Cartesian and joint coordinates 被引量:1
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作者 Sung Soo Kim Wan Hee Jeong +1 位作者 Myung Ho Kim Jong Boo Han 《Theoretical & Applied Mechanics Letters》 CAS 2012年第6期65-70,共6页
The subsystem synthesis method has been developed in order to improve computational efficiency for a multibody vehicle dynamics model. Using the subsystem synthesis method, equations of motion of the base body and eac... The subsystem synthesis method has been developed in order to improve computational efficiency for a multibody vehicle dynamics model. Using the subsystem synthesis method, equations of motion of the base body and each subsystem can be solved separately. In the subsystem synthesis method, various coordinate systems can be used and various integration methods can be applied in each subsystem, as long as the effective mass matrix and the effective force vector are properly produced. In this paper, comparative study has been carried out for the subsystem synthesis method with Cartesian coordinates and with joint relative coordinates. Two different integration methods such as an explicit integrator and an explicit implicit integrator are employed. In order to see the accuracy and computational efficiency from the different models based on the different coordinate systems and different integration methods, a rough terrain run simulations has been carried out with a 6 × 6 off-road multibody vehicle model. 展开更多
关键词 subsystem synthesis method differential algebraic equations
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Lipschitz Shadowing Property for 1-Dimensional Subsystems of Z^(k)-Actions 被引量:5
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作者 Lin WANG Jinlian ZHANG 《Journal of Mathematical Research with Applications》 CSCD 2021年第6期615-628,共14页
In this paper,the shadowing property for 1-dimensional subsystems of Z^(k)-actions is investigated.The concepts of pseudo orbit and shadowing property for 1-dimensional subsystems of Z^(k)-actions are introduced in tw... In this paper,the shadowing property for 1-dimensional subsystems of Z^(k)-actions is investigated.The concepts of pseudo orbit and shadowing property for 1-dimensional subsystems of Z^(k)-actions are introduced in two equivalent ways.For a smooth Z^(k)-action T on a closed Riemannian manifold,we propose a notion of Anosov direction via the induced nonautonomous dynamical system.Adapting Bowen’s geometric method to our case,we show that T has the Lipschitz shadowing property along any Anosov direction. 展开更多
关键词 Z^(k)-actions Lipschitz shadowing 1-dimensional subsystem
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Prototype for Integrating Internet of Things and Emergency Service in an IP Multimedia Subsystem for Wireless Body Area Networks 被引量:1
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作者 Kai-Di Chang Jiann-Liang Chen Han-Chieh Chao 《ZTE Communications》 2014年第3期30-37,共8页
In recent years, the application of the Internet of Things (IoT) has become an emerging business. The most important concept of next-generation network for providing a common global IT platform is combining seamless... In recent years, the application of the Internet of Things (IoT) has become an emerging business. The most important concept of next-generation network for providing a common global IT platform is combining seamless networks and networked things, objects or sensors. Also, wireless body area networks (WBANs) are becoming mature with the widespread usage of the IoT. In order to support WBAN, the platform, scenario and emergency service are necessary due to the sensors in WBAN being related to wearer&#39;s life. The sensors on the body detect a lot of information about bioinformatics and medical signals, such as heartbeat and blood. Thus, the integration of IoT and network communication in daily life is important. However, there is not only a lack of common fabric for integrating IoT with current Internet and but also no emergency call process in the current network communication envi-ronment. To overcome such situations, the prototype of integrating IoT and emergency call process is discussed. A simulated boot-strap platform to provide the discussion of open challenges and solutions for deploying IoT in Internet and the emergency commu-nication system are analyzed by using a service of 3GPP IP multimedia subsystem. Finally, the prototype for supporting WBAN with emergence service is also addressed and the performance results are useful to service providers and network operators that they can estimate their migration to IoT by referring to this experience and experiment results. Furthermore, the queuing model used to achieve the performance of emergency service in IMS and the delay time of the proposed model is analyzed. 展开更多
关键词 loT WBAN radio frequency identification (RFID) emergency service IP multimedia subsystem
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A smartcard conditional access interface scheme for conditional access subsystem separation in digital TV broadcasting 被引量:2
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作者 XIE Qiang ZHENG Shi-bao YU Xiao-jing 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2006年第6期1008-1017,共10页
Conditional access system (CAS) is a key technical component in digital TV broadcasting through which TV op-erators manage the appropriate rights of different subscribers in order to protect their commercial benefits.... Conditional access system (CAS) is a key technical component in digital TV broadcasting through which TV op-erators manage the appropriate rights of different subscribers in order to protect their commercial benefits. The normal digital TV receiver can only receive and decode the pay TV programs scrambled by one specific CAS. In this paper, the authors proposed a smartcard conditional access interface (SCAI) scheme in order to make the digital TV receiver be a common receiving platform independent of any specific CAS employed at the broadcasting head-end. As a result, it only needs to include a common condi-tional access software package (CCAP) without any requirement of hardware modification in the receiver. Comparison between the two mentioned DVB-CI-based schemes showed that the cost of such kind receiver is greatly reduced. The main design points of the proposed scheme and its reference implementation’s architecture are presented in this paper. This scheme is also one of the candidate national standards for Chinese digital TV broadcasting industry. 展开更多
关键词 Digital TV broadcasting Conditional access subsystem separation Smartcard interface
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