期刊文献+
共找到12篇文章
< 1 >
每页显示 20 50 100
工作流过程模型结构性冲突中死锁的探测 被引量:1
1
作者 顾华江 王华 邵培南 《计算机工程》 EI CAS CSCD 北大核心 2006年第16期70-71,88,共3页
从业务流程模型静态结构的角度分析了业务过程模型的结构性冲突中死锁发生的可能性。为了能够更清晰地阐述问题,引入两个概念——可达性和绝对可传输性,用来表示一个节点的输出点和另外一个节点的输入点之间的连接属性。阐述了死锁发生... 从业务流程模型静态结构的角度分析了业务过程模型的结构性冲突中死锁发生的可能性。为了能够更清晰地阐述问题,引入两个概念——可达性和绝对可传输性,用来表示一个节点的输出点和另外一个节点的输入点之间的连接属性。阐述了死锁发生的情形并将之归结为5种模式,并说明了如果一个业务模型中存在与这5种死锁类型中的某一个模型相匹配的结构,那么这个业务模型就存在死锁的可能。 展开更多
关键词 工作流 结构冲突 死锁 可达 绝对可传输性
下载PDF
地理信息特点的研究 被引量:15
2
作者 闾国年 吴平生 +1 位作者 陈钟明 钱亚东 《南京师大学报(自然科学版)》 CAS CSCD 2000年第2期120-124,共5页
地理信息基本特点的研究是当前地理信息科学基础研究重要内容之一 .根据地理信息产生、传输和转化的规律 ,作者将地理信息的特点归纳为客观存在性与抽象性、时空性与属性、可存储性与可传输性、可度量性与近似性、可转换性与可扩充性、... 地理信息基本特点的研究是当前地理信息科学基础研究重要内容之一 .根据地理信息产生、传输和转化的规律 ,作者将地理信息的特点归纳为客观存在性与抽象性、时空性与属性、可存储性与可传输性、可度量性与近似性、可转换性与可扩充性、商品性与共享性等特征 . 展开更多
关键词 地理信息 时空特征 特征 可存储 可传输性
下载PDF
A Novel Built-in CMOS Temperature Sensor for VLSI Circuits 被引量:3
3
作者 王乃龙 张盛 周润德 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2004年第3期252-256,共5页
A novel temperature sensor is developed and presented especially for the purpose of on-line thermal monitoring of VLSI chips.This sensor requires very small silicon area and low power consumption,and the simulation re... A novel temperature sensor is developed and presented especially for the purpose of on-line thermal monitoring of VLSI chips.This sensor requires very small silicon area and low power consumption,and the simulation results show that its accuracy is in the order of 0.8℃.The proposed sensor can be easily implemented using regular CMOS process technologies,and can be easily integrated to any VLSI circuits to increase their reliability. 展开更多
关键词 temperature sensor thermal testability frequency-output
下载PDF
信息六大特征
4
《内蒙古社会科学》 1984年第2期60-60,共1页
(1)可扩充性。信息随着时间日新月异地变化,大部分的信息将不断扩充,人对太阳的认识不断扩充就是一例。(2)可压缩性。人对信息进行加工、整理、概括、归纳就可使之精炼,从而“浓缩”。(3)可替代性。信息的利用可以代替资本、劳力和物质... (1)可扩充性。信息随着时间日新月异地变化,大部分的信息将不断扩充,人对太阳的认识不断扩充就是一例。(2)可压缩性。人对信息进行加工、整理、概括、归纳就可使之精炼,从而“浓缩”。(3)可替代性。信息的利用可以代替资本、劳力和物质材料。 展开更多
关键词 可传输性 可扩充 可替代 物质材料 传输信息 传递信息 可压缩 光速 劳力 工业革命
下载PDF
A novel MAC mechanism to resolve 802.11 performance anomaly 被引量:7
5
作者 CHENG Yan-hong LI Zhi-shu +1 位作者 XING Jian-chuan ZHU Li 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2007年第10期1573-1583,共11页
In the 802.11b networks, the guarantee of an equal long-run channel access probability causes performance anomaly in a multi-rate wireless cell. Much interest has been involved in this issue and many effective mechani... In the 802.11b networks, the guarantee of an equal long-run channel access probability causes performance anomaly in a multi-rate wireless cell. Much interest has been involved in this issue and many effective mechanisms have been proposed. The usual MAC layer solutions include the initial contention window adaptation, the maximum transfer unit size adaptation and the packet bursting. In this paper, we propose a novel approach which introduces a new parameter called the transmission prob- ability pt to the legacy protocol. By adjusting pt according to the transmission rate, the proposed scheme can solve the performance anomaly problem cleanly. Throughput analysis and performance evaluation show that our scheme achieves significant im- provement in the aggregate throughput and the fairness. 展开更多
关键词 IEEE 802.11 WLAN Transmission probability Performance anomaly
下载PDF
Peer priority based data scheduling algorithm in P2P streaming system
6
作者 任浩 Wang Jinlin You Jiali 《High Technology Letters》 EI CAS 2013年第2期208-213,共6页
In order to solve the problem that the existing data scheduling algorithm cannot make full use of neighbors' bandwidth resources when allocating data request among several senders in the multisender based P2P stre... In order to solve the problem that the existing data scheduling algorithm cannot make full use of neighbors' bandwidth resources when allocating data request among several senders in the multisender based P2P streaming system,a peer priority based scheduling algorithm is proposed.The algorithm calculates neighbors' priority based on peers' historical service evaluation as well as how many wanted data that the neighbor has.The data request allocated to each neighbor is adjusted dynamically according to the priority when scheduling.Peers with high priority are preferred to allocate more data request.Experiment shows the algorithm can make full use of neighbors' bandwidth resources to transmit data to reduce server pressure effectively and improve system scalability. 展开更多
关键词 peer-to-peer (P2P) STREAMING data scheduling PRIORITY request allocation
下载PDF
Adjustable transmission properties through ring-shaped nanotube arrays using finite-difference time-domain method
7
作者 周凤麒 刘志敏 +1 位作者 李宏建 刘二根 《Journal of Central South University》 SCIE EI CAS 2014年第8期3013-3018,共6页
Metallic ring-shaped nanotube arrays are proposed and its optical transmission properties are studied by using finite-difference time-domain (FDTD) method. Compared with the transmission spectra of conventional circ... Metallic ring-shaped nanotube arrays are proposed and its optical transmission properties are studied by using finite-difference time-domain (FDTD) method. Compared with the transmission spectra of conventional circular nanotube arrays, two photonic band gaps are emerged in the transmission spectra offing-shaped nanotube arrays, the two band gaps and transmission spectra are adjusted by the length, inner radius, intertube spacing and the dielectric constants of the core and embedding medium, and magnitude modification, redshift and blueshift of the resonance modes are observed. A metallic ring-shaped nanotube arrays for subwavelength band-stop filter in the range of visible light can be achieved. To understand its physical origin, field-interference mechanism was suggested by the field distributions. The proposed nanostructures and results may have great potential applications in subwavelength near-field optics. 展开更多
关键词 ring-shaped nanotube arrays PLASMON transmission spectrum finite-difference time-domain (FDTD) OPTIMIZATION
下载PDF
A Multi-homed VPN Architecture Based on Extended SOCKS+TLS Protocols
8
作者 张宝良 胡汉平 陈翔 《Journal of Shanghai Jiaotong university(Science)》 EI 2005年第3期250-255,共6页
A multi-homed VPN architecture based on extended SOCKSv5 and TLS was proposed. The architecture employs a dynamic connection mechanism for multiple proxies in the end system,i n which the security-demanded transmissio... A multi-homed VPN architecture based on extended SOCKSv5 and TLS was proposed. The architecture employs a dynamic connection mechanism for multiple proxies in the end system,i n which the security-demanded transmission connections can switch smoothly among the multiple proxies by maint aining a coherent connection context.The mechanism is transparent to application programs and can support th e building of VPN.With the cooperation of some other security components,the mechanism guarantees the reso urce availability and reliability of the end system against some attacks to the specific ports or hosts. 展开更多
关键词 multi-homed SOCKSv5 security connection context virtual private network (VPN)
下载PDF
Robust and Scalable P2P Live Streaming
9
作者 陈锬 熊馨 《Journal of Donghua University(English Edition)》 EI CAS 2009年第5期482-488,共7页
Distributing real-time video stream in large scale group communication over Interuet poses several challenging problems due to the complex network dynamics, stringent requirement of delay and loss. This paper proposes... Distributing real-time video stream in large scale group communication over Interuet poses several challenging problems due to the complex network dynamics, stringent requirement of delay and loss. This paper proposes a novel peer-to-peer scheme, named TeamCast, to combat with these issues. Constructing multiple diverse application layer multicast (ALM) trees to transmit multiple independent complementary descriptions produced by multiple description coding (MDC) simultaneously, TeamCast improves error resilient ability in the presence of various levels of packet loss caused by unpredictable congestion of Internet and node failure, as well as enlarges system capacity. The results of extensive simulations indicate that TeamCast achieves low latency, scalability, and fault tolerance for the delivery of live media stream. 展开更多
关键词 path diversity multiple description coding application layer multicast media streaming topologyuware
下载PDF
Research of CAN Bus in the Coal Mine Field Data Transmission based on Reliability
10
作者 LUO Li 《International Journal of Technology Management》 2014年第8期83-85,共3页
Under the current situation, China' s rapid economic development, various new science, emerge in an endless stream of new technology, under the environment of coal mine industry, seize the opportunity, by virtue of i... Under the current situation, China' s rapid economic development, various new science, emerge in an endless stream of new technology, under the environment of coal mine industry, seize the opportunity, by virtue of its original advantages, coupled with technology introduction and innovation consciousness of the play, ushered in a new period of development, into the modern coal mining era. CAN bus technology is a new technology which has the typical data transmission in coal mining, the introduction of a certain degree of CAN bus technology, not only improve the efficiency of data transmission, at the same time, in terms of reliability and greatly enhance. In this paper, to a certain extent on the introduction of the CAN bus technology, and on this basis, based on the CAN bus in the coal mine field data transmission reliability research and analysis 展开更多
关键词 CAN Bus Underground Coal Mines Field Bus Control System Data Transmission Reliability
下载PDF
松下电器开发出可传输视频图像的芯片组
11
《中外科技信息》 北大核心 2003年第4期76-76,共1页
关键词 视频图像 芯片组 日本松下电器公司 信号处理 可传输性
原文传递
Tunable slow-light multi-mode photonic crystal waveguides based on the coupling of square cavities 被引量:5
12
作者 FENG Shuai YANG GuoJian +3 位作者 LI YuXi CHEN Xiao WANG YiQuan WANG WenZhong 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2012年第10期1769-1775,共7页
The light transmission properties through two-dimensional photonic crystal waveguides based on coupling of square cavities are studied by the finite-difference time-domain technique.Through interlacing the adjacent ca... The light transmission properties through two-dimensional photonic crystal waveguides based on coupling of square cavities are studied by the finite-difference time-domain technique.Through interlacing the adjacent cavities along the direction vertical to the waveguide,the coupling distance between the adjacent cavities is extended,and the group velocity of the guiding modes can be slowed by five-fold compared with that in vacuum.Because of the different spatial field distributions of various resonant modes,the corresponding group velocities are also different for the same CROW structure. 展开更多
关键词 photonic crystal coupled-resonator optical waveguide group velocity
原文传递
上一页 1 下一页 到第
使用帮助 返回顶部