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91.
垃圾焚烧站的PLC集散控制系统设计 总被引:1,自引:1,他引:1
垃圾焚烧技术作为目前城市处理垃圾的主要手段,得到了比较广泛的应用。简单阐述了垃圾焚烧的工艺流程。并以浙江诸暨某垃圾焚烧站为例,介绍该垃圾焚烧站的整体设计,包括建立了一个基于西门子S7系列PLC为硬件基础的集散控制系统,且人机界面采用了国内流行的亚控组态王工控软件进行开发。除此,还介绍了一种神经网络PID控制算法实现对焚烧温度的控制,给出了该算法在监控界面上的一个仿真结果,进而验证了该算法的可行性。 相似文献
92.
93.
Hangyang Dai Hongbing Xu 《Frontiers of Electrical and Electronic Engineering in China》2009,4(3):300-306
For security services in wireless sensor networks, key management is a fundamental building block. In this article, we propose
a triangle-based key predistribution approach and show that it can improve the effectiveness of key management in wireless
sensor networks. This is achieved by using the bivariate polynomial in a triangle deployment system based on deployment information
about expected locations of the sensor nodes. The analysis indicates that this scheme can achieve higher probability of both
direct key establishment and indirect key establishment. On the other hand, the security analysis shows that its security
against node capture would increase with a decrease of the sensor node deployment density and size of the deployment model
and an increase of the polynomial degree. 相似文献
94.
95.
Due to power considerations, it is possible that not all wavelengths available in a fiber can be used at a given time. In this paper, an analytical model is proposed to evaluate the blocking performance of wavelength-routed optical networks with and without wavelength conversion where the usable wavelengths in a fiber is limited to a certain maximum number, referred to as wavelength usage constraint. The effect of the wavelength usage constraint is studied on ring and mesh-torus networks. It is shown that the analytical model closely approximates the simulation results. We also evaluate the performance of the first-fit wavelength assignment algorithm and compare its performance with the random wavelength assignment algorithm through simulation. It is observed that increasing the total number of wavelengths in a fiber is an attractive alternative to wavelength conversion when the number of usable wavelengths in a fiber is maintained the same. 相似文献
96.
There are protocols that can be used by mobile clients to discover service providers in foreign networks to which they get attached, e.g., SDP of Bluetooth and SLP of IETF. These protocols do address service discovery, but do not address the selection of a service provider among a set of candidates according to a physical proximity of the client and service provider. The goal of the research described in this paper is to integrate proximity-based selection mechanisms to service discovery protocols. We present in this paper protocols that allow nomadic clients to discover and select service providers according to physical proximity. 相似文献
97.
在无线传感器网络中,节点具有有限的电池能量,为了延长网络的生存时间,提出了一种基于生成树的分布式路由协议STRP及其具有能量意识的改进版本STRP-PA.每个传感器节点根据相邻节点与基站的距离、剩余能量等信息寻找父节点,构造一棵以基站为根的近优最小生成树,节点采集的数据沿树传输,并在树杈节点进行聚合.仿真实验结果表明:STRP-PA协议能够节省网络能量,显著延长网络稳定工作的时间,性能明显好于LEACH协议. 相似文献
98.
旋转机械是许多大型生产设备系列中不可缺少的关键设备,必须对设备进行实时监控。把传感器节点布置在旋转机械的有利测量点上采集数据,通过软硬系统平台搭建,实现无线传感器网络传输,在监控诊断中心由专家系统进行诊断,然后实现远程和本地控制,达到对设备进行及时维护和更换。通过系统仿真到达设计要求。 相似文献
99.
Berta Carballido VillaverdeAuthor Vitae Susan Rea Author VitaeDirk Pesch Author Vitae 《Ad hoc Networks》2012,10(3):458-478
Wireless sensor networks are a key enabling technology for industrial monitoring applications where the use of wireless infrastructure allows high adaptivity and low cost in terms of installation and retrofitting. To facilitate the move from the current wired designs to wireless designs, concerns regarding reliability must be satisfied. Current standardization efforts for industrial wireless systems lack specification on efficient routing protocols that mitigate reliability concerns. Consequently, this work presents the InRout route selection algorithm, where local information is shared among neighbouring nodes to enable efficient, distributed route selection while satisfying industrial application requirements and considering sensor node resource limitations. Route selection is described as a multi-armed bandit task and uses Q-learning techniques to obtain the best available solution with low overhead. A performance comparison with existing approaches demonstrates the benefits of the InRout algorithm, which satisfies typical quality of service requirements for industrial monitoring applications while considering sensor node resources. Simulation results show that InRout can provide gains ranging from 4% to 60% in the number of successfully delivered packets when compared to current approaches with much lower control overhead. 相似文献
100.
本文根据主观信任的主观性、模糊性以及随机性特点,基于隶属云理论提出了适合于电信系统中分布式信任模型。 相似文献