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151.
文章对空气质量自动监测系统的异构性问题进行了分析与研究,提出了"抽象设备、映射数据、虚拟协议"的解决方案,将物理设备屏蔽在驱动一级,将抽象设备屏蔽在转换程序一级,将数据按空气质量因子分类型打包传送到组态王对应的寄存器组,实现了不同数据接口、不同数据类型以及不同传送协议下的企业信息自动化。 相似文献
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结合Skyline软件中的Video On Terrain技术提出了一种3DGIS与视频监控系统相集成的三维地面影像视频监控新方案,设计了3DGIS视频监控系统的软硬件框架和数据库,讨论了视频数据传输和编码、视频监控报警流程以及网络分析等关键技术,详细介绍了三维场景的创建过程,最后实现了视频监控与3DGIS集成的原型系统,并分析了系统集成的优势。 相似文献
154.
防范地址解析协议ARP(Address Resolution Protocol)欺骗攻击的难点是:攻击源可以隐藏在网段内任何一个主机中,即使发现了攻击的存在,也难以迅速定位攻击源。结合校园网络的特点,提出了一种新的ARP攻击检测方案:检测服务器通过SNMP协议定期读取核心交换机的ARP、VLAN等信息和接入交换机的MAC-PORT信息,利用综合检测算法,及时发现攻击现象,迅速定位攻击源,并根据网络实际情况采用不同的技术措施进行处理。实践证明,该方法能够有效保障校园网络安全。 相似文献
155.
Alfonso E. Gerevini Patrik Haslum Derek Long Alessandro Saetti Yannis Dimopoulos 《Artificial Intelligence》2009,173(5-6):619-668
The international planning competition (IPC) is an important driver for planning research. The general goals of the IPC include pushing the state of the art in planning technology by posing new scientific challenges, encouraging direct comparison of planning systems and techniques, developing and improving a common planning domain definition language, and designing new planning domains and problems for the research community. This paper focuses on the deterministic part of the fifth international planning competition (IPC5), presenting the language and benchmark domains that we developed for the competition, as well as a detailed experimental evaluation of the deterministic planners that entered IPC5, which helps to understand the state of the art in the field.We present an extension of pddl, called pddl3, allowing the user to express strong and soft constraints about the structure of the desired plans, as well as strong and soft problem goals. We discuss the expressive power of the new language focusing on the restricted version that was used in IPC5, for which we give some basic results about its compilability into pddl2. Moreover, we study the relative performance of the IPC5 planners in terms of solved problems, CPU time, and plan quality; we analyse their behaviour with respect to the winners of the previous competition; and we evaluate them in terms of their capability of dealing with soft goals and constraints, and of finding good quality plans in general. Overall, the results indicate significant progress in the field, but they also reveal that some important issues remain open and require further research, such as dealing with strong constraints and computing high quality plans in metric-time domains and domains involving soft goals or constraints. 相似文献
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Long Cheng Hanlei Wang Zeng-Guang Hou Min Tan 《International journal of systems science》2016,47(8):1966-1981
Consensus problem of high-order integral multi-agent systems under switching directed topology is considered in this study. Depending on whether the agent’s full state is available or not, two distributed protocols are proposed to ensure that states of all agents can be convergent to a same stationary value. In the proposed protocols, the gain vector associated with the agent’s (estimated) state and the gain vector associated with the relative (estimated) states between agents are designed in a sophisticated way. By this particular design, the high-order integral multi-agent system can be transformed into a first-order integral multi-agent system. Also, the convergence of the transformed first-order integral agent’s state indicates the convergence of the original high-order integral agent’s state, if and only if all roots of the polynomial, whose coefficients are the entries of the gain vector associated with the relative (estimated) states between agents, are in the open left-half complex plane. Therefore, many analysis techniques in the first-order integral multi-agent system can be directly borrowed to solve the problems in the high-order integral multi-agent system. Due to this property, it is proved that to reach a consensus, the switching directed topology of multi-agent system is only required to be ‘uniformly jointly quasi-strongly connected’, which seems the mildest connectivity condition in the literature. In addition, the consensus problem of discrete-time high-order integral multi-agent systems is studied. The corresponding consensus protocol and performance analysis are presented. Finally, three simulation examples are provided to show the effectiveness of the proposed approach. 相似文献
160.
We present a refined entanglement concentration protocol (ECP) for an arbitrary unknown less-entangled four-electron-spin cluster state by exploring the optical selection rules derived from the quantum-dot spins in one-sided optical microcavities. In our ECP, the parties obtain not only the four-electron-spin systems in the partial entanglement with two unknown parameters, but also the less-entangled two-electron-spin systems in the first step. Utilizing the above preserved systems as the resource for the second step of our ECP, the parties can obtain a standard cluster state by keeping the robust odd-parity instances with two parity-check gates. Meanwhile, the systems in the rest three instances can be used as the resource in the next round of our ECP. The success probability of our ECP is largely increased by iteration of the ECP process. Moreover, all the coefficients of our ECP are unknown for the parties without assistance of extra single electron-spin, so our ECP maybe has good applications in quantum communication network in the future. 相似文献