12 resultados para city, convergence, digital lifestyle, transdisciplinary research, Korea, network technology, mobile media, open design, play, shared visual ethnography, Seoul, social networking, transyouth, ubiquitous computing, urban ludology, urban networks

em Chinese Academy of Sciences Institutional Repositories Grid Portal


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网络编码允许网络节点在传统数据转发的基础上参与数据处理,已成为提高网络吞吐量、鲁棒性和安全性的有效方法.在介绍网络编码基本原理的基础上,比较了集中式和分布式网络编码构造方法的优缺点,并对实用网络编码设计中涉及的同步、纠错、编解码速度等问题进行了评述;进而,对网络编码在无线网络、P2P系统、分布式文件存储和网络安全等领域的最新应用进行了总结;最后对网络编码的理论和应用研究的发展趋势进行了分析与展望.设计简单高效的实现机制,并与其他领域的技术如信道编码与调制、路由算法、队列调度以及流媒体技术等的结合,将是网络编码发展的一个重要趋势.

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近年来,计算机网络迅速发展,各种网络应用层出不穷,各种网络性能面临挑战。对网络流量进行识别和分类,对网络性能进行测量和分析,已成为计算机网络的一个新兴课题。网络测量能够了解网络的行为特征和性能特征等,是对网络进行规划建设和优化改造的基础。 本文以当前网络测量实际应用为背景,介绍了网络测量技术的发展、分类和商用产品,设计并实现了一种纯软件开发的、扩展性强、有实际应用价值的网络测量系统,并对实现过程中所涉及到的网络流量测量和网络性能测量关键技术作了详细描述。 本文工作主要有如下贡献: 1、提出了以纯软件方法开发网络测量系统的方案; 2、设计了网络测量系统的系统结构及各模块之间的接口; 3、设计并实现了网络流量测量子系统,能够监测和分析从数据链路层到应用层等不同协议层次的流量组成和变化趋势,以及主机对之间和服务器负载上的应用类型和流量,提供实时的和历史的流量统计分析功能,可协助分析和定位网络异常和网络瓶颈; 4、设计并实现了网络性能测量子系统,能够测量网络层端到端的跳数、丢包率、往返延迟、往返延迟抖动等参数,以及HTTP、TELNET、FTP和EMAIL等常见网络业务的应用层性能,协助用户分析影响网络性能的原因。

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随着计算机网络、通信和控制技术的发展,以太网技术在工业控制领域中的应用倍受关注。但控制系统对高可用性和稳定性的要求限制了工业以太网的发展。同时面对国内工业生产的安全现状,基于工业以太网技术的控制系统越来越多的被用于安全仪表系统(Safety Instrumented System SIS)中,所以迫切需要开展总线安全技术的研究工作,提高工业以太网控制系统的安全性和可用性。 为了满足总线控制系统对工业以太网的安全性和可用性要求,本文重点研究了基于工业以太网的高可用性网络技术,提出了三种网络冗余协议,描述了设计和开发过程,最后,通过实验数据给出了性能分析。 论文首先介绍了工业以太网和高可用性网络技术在控制领域的应用情况。分析了目前普遍应用的环网冗余技术,包括通用的生成树协议、快速生成树协议和自动化厂商自己开发的专用环网冗余协议。讨论了以上环网冗余协议在高可用性控制系统中应用的不足。 论文针对环网冗余协议在故障恢复时间等方面的不足,设计了三种基于工业以太网的网络冗余协议:单网冗余协议、双网备份冗余协议和双网并行冗余协议。本文所设计的网络冗余协议都要求将冗余管理下放到节点设备,实现分布式的冗余管理,冗余节点和非冗余节点能够同时在网络中并存,而且所有的冗余管理对于上层应用协议具有透明性。但是每种网络冗余协议在拓扑结构、故障探测和故障恢复方面各不相同。结合EPA(Ethernet for Plant Automation EPA)通信协议栈,选择合适的软硬件环境,本文实现了所设计的三种网络冗余协议,包括协议栈结构,帧结构和通信过程。 为了对网络冗余协议的进行功能测试和性能评估,论文提出了故障恢复时间,故障定位时间等评估指标,在实验室环境下搭建了测试网络平台,针对每个评估指标设计了测试方案,最后给出了每个网络冗余协议的性能和测试结果。

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生产线数字制造环境是数字化工厂的核心 ,而加工过程的仿真与验证技术构成生产线数字系统的底层结构与制造过程数字化分析的主要内容。分析了目前加工过程在几何仿真与物理仿真方面的研究情况、研究方法与存在问题 ,就该项技术向生产线数字制造环境融合的关键技术 ,即综合设备数字样机的完整数字加工环境的建立及加工过程仿真与上层制造环境的信息集成等进行分析与研究

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本文以水下机器人的遥操作作业为应用背景 ,提出并实现了虚拟现实技术和视觉感知信息辅助机器人遥操作实验系统 .该系统使用了 CAD模型和立体视觉信息完成遥操作机器人及其作业环境的几何建模和运动学建模 ,实现了虚拟作业环境的生成和实时动态图形显示 .采用了基于立体视觉的虚拟环境与真实环境的一致性校正、图形图像叠加、作业体与环境位姿关系建立、基于网络的监控通讯等关键技术 .在这个实验系统中 ,操作人员可利用所生成的虚拟环境 ,在多视点、多窗口作业状态图形和图像显示帮助下 ,实时动态地进行作业观测与机器人遥操作与运动规划 ,为先进遥操作机器人系统的实现提供了经验和关键技术 .

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基于网络的SOMR(单操作者操作多机器人)遥操作系统可以通过网络将人的智能与多机器人系统的智能相结合,弥补多机器人自主性的不足,从而使得多机器人能够在复杂的非结构环境下执行任务,大大拓展多机器人系统的应用,因而有着广阔的应用前景。 多机器人系统的复杂性决定了操作者很难直接控制多机器人系统,因而多机器人系统需要具有一定的局部自主协调能力,同时操作者和多机器人系统之间还需要具有良好的交互能力,从而达到人机之间的协调工作。以网络作为操作者与多机器人系统进行交互的媒介,网络的时延、时延抖动、多通道传输等问题将给多机器人遥操作系统带来许多困难。目前,对于单操作者通过网络遥操作多机器人系统的研究还较少。本文在分析了现有的遥操作技术和理论的基础上,对基于网络的SOMR遥操作系统主要进行了以下深入细致的研究: 1. 根据基于网络的SOMR遥操作系统的特点,提出了基于网络的SOMR遥操作系统的体系结构ANSOMR(Architecture for Network based SOMR teleoperation system)。ANSOMR体系结构结合了自上而下和自下而上两种体系结构的优点,并充分考虑了系统中的人机交互,意义明确,易于扩展。 2. 围绕ANSOMR体系结构研究系统中多机器人的局部自主和协调,通过基于行为的方法实现了基于网络的SOMR遥操作系统中机器人的基本自主能力,并为多机器人系统的自主协调建立了分层混杂自动机模型。 3. 在ANSOMR体系结构的交互层中,应用多模式控制的方法丰富了操作者对多机器人系统的操作和控制手段,并通过集成多模式控制接口、超媒体反馈和操作界面构成了基于网络的SOMR遥操作系统的人机交互接口,实现了多机器人系统的自主与操作者能力的结合。 4. 研究了网络时延对多机器人遥操作系统的影响,应用基于事件的方法保证了系统的稳定性,并在此基础上提出了一种带有时间标记的基于事件的方法,将基于事件的方法与基于时间的多机器人系统的局部自主规划结合了起来,解决了事件之间的时延对操作者与多机器人系统之间交互的影响,从而提高了系统的效率。 5. 将网络遥操作技术应用于足球机器人系统,建立了基于网络的遥操作足球机器人系统作为实验平台,应用ANSOMR体系结构,封装了足球机器人的基本行为,分析了机器人足球比赛的状态空间,应用分层混杂自动机模型实现了足球机器人的角色分配和行为选择,并为系统设计了人机交互接口,从而使实验系统成为了一个典型的基于网络的SOMR遥操作系统。 通过在实验系统中应用各种模型和方法,对理论和方法的研究进行了实验验证,实验结果证明了所提出的方法是有效可行的,对于建立性能良好的基于网络的SOMR遥操作系统具有现实意义。

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文章研究了基于客户端/服务器(C/S)模式的多水下机器人仿真平台中网络通信的关键技术。文章介绍了该仿真平台的结构和功能,分析了仿真平台的信息流向和通信特点,在此基础上,提出了适合该仿真平台应用的网络通信协议和时钟同步方案,并详细讨论了Windows和QNX两种不同操作系统上的应用程序之间进行网络通信的实现方法。

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As a kind of special lithologic ones, Igneous rock oil and gas pool is more and more paid attention, and it has different forming condition and distribution from conventional ones, such as various terrane distribution types, serious reservoir anisotropy, complicated hydrocarbon-bearing, so there is not successful experience to follow for exploration and development of this complex subtle oil and gas pool at present. For an example of Igneous oil and gas pool of Luo151 area in Zhanhua seg, Eastern China, this article study the difficult problem, including petrologic nd lithofacies analysis, Origin, invasion age and times of Igneous rock, reservoir anisotropy, Geological Modeling, Igneous reservoir synthesis evaluation. forming condition and distribution are studied synthetically, and an integrated method to predict igneous rock oil and gas pool is formed, which is evaluated by using development data. The Igneous rock is mainly diabase construction in Luo151 area of Zhanhua Sag, and petrologic types include carbonaceous slate, hornfels, and diabases. Based on analyzing synthetically petrologic component, texture and construct, 4 lithofacies zones, such as carbonaceous slate subfacies, hornfels subfacies containing cordierite and grammite, border subfacies and central subfacies, are divided in the diabase and wall rock. By studying on isotopic chronology, terrane configuration and imaging logging data, the diabase intrusion in Zhanhua Sag is formed by tholeiite magma emplacing in Shahejie formation stratum on the rift tension background Lower Tertiary in North China. The diabase intrusion of Luo151 is composed possibly of three periods magma emplacement. There is serious anisotropy in the diabase reservoirs of Luo151 in Zhanhua Sag. Fracture is primary reservoir space, which dominated by tensile fracture in high obliquity, and the fracture zones are mainly developed round joint belt of igneous rock and wall rock and position of terrane thickness changing rapidly. The generation materials of the reservoirs in Luo151 igneous oil pools consist of Intergranular micropore hornfels, condensate blowhole-solution void diabase condensate edge, the edge and center of the condensate seam diabase, of which are divided into horizontal, vertical and reticulated cracks according fracture occurrence. Based on the above research, a conceptual model of igneous rock reservoir is generated, which is vertically divided into 4 belts and horizontally 3 areas. It is built for the first time that classification evaluation pattern of igneous rock reservoir in this area, and 3 key wells are evaluated. The diabase construction is divided into grammite hornfels micropore type and diabase porous-fracture type reservoirs. The heavy mudstone layers in Third Member of Shahejie formation (Es3) provide favorable hydrocarbon source rock and cap formation, diabase and hornfels belts serve as reservoirs, faults and microcracks in the wall rocks as type pathways for oil and gas migration. The time of diabase invasion was about in the later deposition period of Dongying Formation and the middle of that of Guantao Formation, the oil generated from oil source rock of Es3 in the period of the Minghuazhen formation and is earlier more than the period of diabase oil trap and porous space forming. Based on geological and seismic data, the horizon of igneous rocks is demarcated accurately by using VSP and synthetic seismogram, and the shape distribution and continuity of igneous rocks are determined by using cross-hole seismic technology. The reservoir capability is predicted by using logging constraining inversion and neural network technology. An integrated method to predict igneous rock oil and gas pool is formed. The study is appraised by using development data. The result show the reservoir conceptual model can guide the exploration and development of oil pool, and the integrated method yielded marked results in the production.

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Aim at the variousness and complexity of the spatial distribution of Remaining Oil in the fluvial and delta facies reservoir in paper. For example, in the La-Sa-Xing oilfield of Daqing, based on the research of the control factor and formation mechanization of block, single layer, interlayer and micromechanism, synthesizing the theories and methods of geology, well logging, reservoir engineering, artificial intelligence, physical simulation test , and computer multidisciplinary; Fully utilizing the material of geology, well logging, core well, dynamic monitor of oil and water well, and experimental analysis, from macro to micro, from quality to quantity, from indoor to workplace, we predicted the potentiality and distribution according to the four levels of Block, single layer, interlayer and micromechanism, and comprehensively summarized the different distribution pattern of remaining oil in the fluvial and delta facies reservoir This paper puts forward an efficient method to predict the remaining recoverable reserves by using the water flooding characteristic curve differential method and neutral network; for the first time utilizes multilevel fuzzy comprehensive judgment method and expert neutral network technology to predict the remaining oil distribution in the single layer? comprehensively takes advantage of reservoir flowing unit, indoor physical simulation test, inspection well core analysis and well-logging watered-out layer interpretation to efficiently predict the distribution of remaining oil; makes use of core analysis of different periods and indoor water driving oil test to study the micro distribution of remaining oil and the parameters varying law of reservoir substance properties, rock properties, wetting properties. Based on above, the remaining oil distribution predicting software is developed, which contains four levels of block, single layer, interlayer and micromechanism. This achievement has been used inLa-Sa-Xing oil field of Daqing and good results have been received.