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21.
Qian?LiEmail author Wenjia?Niu Gang?Li Endong?Tong Yue?Hu Ping?Liu Li?Guo 《Journal of Network and Systems Management》2015,23(3):474-501
With the motivation of seamlessly extending wireless sensor networks to the external environment, service-oriented architecture comes up as a promising solution. However, as sensor nodes are failure prone, this consequently renders the whole wireless sensor network to seriously faulty. When a particular node is faulty, the service on it should be migrated into those substitute sensor nodes that are in a normal status. Currently, two kinds of approaches exist to identify the substitute sensor nodes: the most common approach is to prepare redundancy nodes, though the involved tasks such as maintaining redundancy nodes, i.e., relocating the new node, lead to an extra burden on the wireless sensor networks. More recently, other approaches without using redundancy nodes are emerging, and they merely select the substitute nodes in a sensor node’s perspective i.e., migrating the service of faulty node to it’s nearest sensor node, though usually neglecting the requirements of the application level. Even a few work consider the need of the application level, they perform at packets granularity and don’t fit well at service granularity. In this paper, we aim to remove these limitations in the wireless sensor network with the service-oriented architecture. Instead of deploying redundancy nodes, the proposed mechanism replaces the faulty sensor node with consideration of the similarity on the application level, as well as on the sensor level. On the application level, we apply the Bloom Filter for its high efficiency and low space costs. While on the sensor level, we design an objective solution via the coefficient of a variation as an evaluation for choosing the substitute on the sensor level. 相似文献
22.
李刚 《计算机光盘软件与应用》2011,(6)
本文依据交换机与路由器学科技术的特点及教学实践中存在的现实问题,展开了对教材建设、教学手段及教学模式的全面探讨,并制定了科学有效的实践教学改革策略,对提升交换机与路由器技术课程教学效果水平有重要的推进作用. 相似文献
23.
本文介绍所设计的一种带GPS定位和GSM通讯功能的野外测量终端模型系统。系统采用μC/OS-II嵌入式实时操作系统,以基于ARM并辅以GSM和GPS模块为硬件平台,提供给野外测量终端用户基本的通话功能和个人定位信息,为实时采集地理信息作基础。 相似文献
24.
25.
秦二厂固体废物处理系统装桶站存在成本高、固化质量差等缺陷,需进行技术改造以满足更高的管理和安全要求.改造将原浓缩液和废树脂的承运容器由水泥桶变更为金属桶,同时将原二站和四站设备进行变更,以配合金属桶的自动取封盖、树脂与水的精确测量.主要介绍了改造后系统控制实现方式、主要设备原理、施工过程及遇到的问题和处理办法。 相似文献
26.
Research on the group decision-making about emergency event based on network technology 总被引:1,自引:1,他引:0
Kefan Xie Gang Chen Qian Wu Yang Liu Pan Wang 《Information Technology and Management》2011,12(2):137-147
In order to improve decision-making efficiency about emergency event, this paper proposes a novel concept, i.e., Agile-Delphi
Method, which is an integration of agile decision and Delphi Method implicating that the decision-makers instantly deliver,
respond, treat, and utilize information via Delphi process while conducting group decision-making about emergency event. The
paper details the mechanism of group decision-making about emergency event based on network technology and Agile-Delphi Method.
Finally, the paper conducts an empiric analysis taking the “111 event”, i.e., the liquid ammonia spill event happened on November
1, 2006 in a phosphorus chemical company in China, as an example. 相似文献
27.
In this paper, a novel structure is derived for efficient implementation of digital filters as well as minimizing the finite word length (FWL) errors. Such a structure is actually an improved version of that reported previously. The performance of this new structure and the famous normalized lattice structure are analyzed by deriving the corresponding expression for the roundoff noise gain. Design examples are presented to illustrate the behavior of the proposed structure and to compare it with some existing ones. It is shown that the proposed structure outperforms the others in terms of minimizing roundoff noise as well as implementation efficiency. 相似文献
28.
In this paper, we shall establish sufficient conditions for the existence of mild solutions for nonlocal impulsive differential inclusions. On the basis of the fixed point theorems for multivalued maps and the technique of approximate solutions, new results are obtained. Examples are also provided to illustrate our results. 相似文献
29.
介绍了冬季供暖水循环泵节能控制方法,采用了传统PID结合温度模糊控制和PWM的方法.可预设转折频率、转折延时、不同温度段脉冲频率上、下限值,节能控制柜根据出水管和回水管两者温差通过PID算法调节水泵运转频率,当水泵运转频率低于转折频率,转折延时后,采用PWM方式;若水泵运转频率高于转折频率,则进入模糊PID调节.PWM技术的应用,使得供暖温度能够结合室外大气温度进行实时调控.该方法在满足用户的温度需求前提下,可使水泵电机节能30%以上. 相似文献
30.
Multimedia Tools and Applications - Aiming for the problem detection of infrared imaging aerial small target under complex background, an intelligent algorithm is presented based on digital image... 相似文献