Logical sensor systems

Multisensor systems require a coherent and efficient treatment of the information provided by the various sensors. We propose a framework, the Logical Sensor Specification System, in which the sensors can be defined abstractly in terms of computational processes operating on the output from other sensors. Various properties of such an organization are investigated, and a particular implementation is described.     

基于无线传感器网络的分组加密算法的设计

为了适应传感器网络的发展,应对传感器节点计算能力和存储资源的限制,基于无线传感器网的WSW(Wireless Sensor Whisper,无线传感耳语算法)算法是一种专门针对传感器能力限制而提出的分组加密算法。WSW算法通过扩展基本逻辑运算获得256种不同的加密方式,同时通过在算法中引入随机选择算法来增强算法的安全性,该算法使用的加密方法和随机选择可以减少节点运算次数,使得节点数据保证安全的同时能量及时间消耗也尽可能减少。     

传感器故障检测、分离与恢复的神经网络方法

传感器是测控系统不可缺少的部件,传感器数据的高可靠性是系统正常工作的重要保证,本文基于递归神经网络具有优良的动态系统建模能力和时间数据序列预报区能力,融合时空信息,构造出具有传感器故障检测,分离和故障恢复能力的智能传感器系统,理论 仿真结果表明,所研究系统的优良性能。     

Design of modified PD algorithm to control angular motion of large space structure

Consideration was given to the design of an algorithm to control orientation of the large space structure (LSS) in the presence of infralow (less than 0.01Hz) frequencies of elastic oscillations exerting considerable influence on the quality of transients due to closeness of the LSS eigenfrequencies to the frequency of control of the object’s “rigid” motion. Procedure for designing a modified PD-algorithm for orientation of the LSS with infralow frequencies of elastic structural oscillations was described. Methods were proposed for calculation of the coefficients of additional components of the modified algorithm and determination of the LSS eigenfrequency boundary to the right of which the orientation control system is robust to the deviations of the object frequencies or inaccuracy of their definition. Some examples of mathematical modeling of the processes of the relay gyroforce control of LSS orientation using the proposed algorithm were given.     

无线传感器网络中信道接入分簇算法的研究

传感器技术、微机电系统、现代网络和无线通信等技术的进步,推动了具有现代意义的无线传感器网络的产生和发展。无线传感器网络能够广泛应用于恶劣环境和军事领域中。其中针对如何延长传感器网络的生存周期,降低传感节点的能量消耗成为研究的重点问题。文章通过分析无线传感器网络的特点和分簇算法的优点,提出新的基于信道接入分簇算法的路由解决方案,通过与已有的基于信道接入分簇算法的比较,新的分簇算法能够大大降低系统的能耗和复杂度,延长网络的寿命。最后,利用OPNET网络仿真工具给出相关的仿真结果。     

一种新型数字式角度传感器的研究

随着设备对角度的高精度检测的需求不断增加,研制一种精度高、寿命长的传感器十分必要。采用增量式光电编码器和可编程序控制器的全新设计,较好地解决了这一问题。角度全量程的最高分辨率为0.09°。实践表明性能指标满足工艺要求。由于采用光电传感,系统检测过程无磨损,可靠性高,已大量应用在诸如焊丝高精度层绕机、子午线轮胎纤维帘布裁断机等各种精加工设备上。     

Scale-free,self-organizing very large sensor networks

In this paper we introduce SFSN, an algorithm for self-organization of Very Large Sensor Networks (VLSN). The 10⁶ or more tiny and inexpensive sensors of a VLSN are indistinguishable from one another; they do not have either a physical or a logical address, as required by the traditional communication protocols. The self-organization scheme limits the number of partners each sensor collaborates with, thus, it limits the amount of communication and the complexity of coordination. The system is scalable, the amount of state information each node has to maintain is strictly limited regardless of the total number of sensors in the network. The systems we consider mimic biological systems where individual cells of the same type are indistinguishable.     

An implementation of disk objects in the logical machine monitor

User or program mobility in distributed computing systems is becoming increasingly significant, since users may sometimes change their working locations. This paper proposes a Logical Machine (LM) system that can effectively support software environment migration and resource mapping. The LM partitions the conventional operating systems into two parts: the Logical Machine Operating System (LMOS) and the Logical Machine Monitor (LMM). They are responsible for user service and system resource management, respectively. The LMM provides a machine independent appearance, called the Logical Machine Interface (LMI), for the upper operating system layers to provide the resources they need. In our experimental system, the LMM contains some disk objects that can be bound dynamically. By varying the binds, the users get different disk characteristics. A mobile disk object with the mechanism of block migration on demand is implemented. It can be incorporated with a logical machine migration facility to achieve job migration, i.e., the user can migrate the operating system and disk blocks to the place he or she desires. The mobile disk also simplifies the mechanism of parallel processing when each server reads and processes its data portion locally. With this approach, the system resources can be mapped more flexibly, while transparency to the operating system is retained. © 1997 John Wiley & Sons, Ltd.     

基于大规模智能电网网格结构的查询方法

由于智能电网输电线路监测系统的查询多数是针对无线传感器网络(WSN)的全局式查询,不能满足用户基于任意区域的灵活高效的查询需求,根据该系统的网络布局和查询特点,提出了一种基于大规模智能电网网格结构的查询方法MSQuery。MSQuery将不同网格内的查询节点的数据汇聚到一棵或多棵逻辑查询树上, 采用逻辑查询树的合并策略建立优化的回收路径。将MSQuery与采用路线型结构进行查询的RSA算法和采用簇型结构进行查询的SkySensor算法进行对比,结果显示MSQuery的平均传输消耗最小,平均剩余能量最大。实验结果表明,MSQuery可以快速地返回查询窗口内的查询结果,降低通信消耗,节省传感器节点能量。     

De-Coupling for Re-Use in Design and Implementation Using Virtual Sensors

ViSIAr (Virtual Sensor Integration Architecture) is an idealised framework for building sensing subsystems of flexible assembly and other robotic systems. This paper considers how it supports the design and analysis phase, and might therefore support the exchange of software solutions to sensing problems, by clearly identifying the role and function of software components and de-coupling them from specific hardware. Sensor usage models, specifications of what is to be sensed and the way in which it is sensed, are proposed as the principal objects suitable for design re-use and potentially for code re-use. Generally applicable classes of virtual sensor control models (which form part of sensor usage models) are presented.     

WSN SnSim:一种无线传感网络仿真平台的研究与实现

随着无线传感网络技术的研究逐渐深入,对于无线传感网络仿真平台的需求也受到越来越多的重视.为了更加方便有效地进行无线传感网络上的算法研究,设计实现了一种无线传感网络仿真平台SnSim (Sensor Network Simulator).针对目前无线传感网络的发展情况,结合无线传感网络的特点,采用目前流行的Eclipse RCP面向对象框架,设计了无线传感网络仿真平台的数学模型、体系结构、功能模块、平台语言.实现了无线传感网络仿真平台,并对其性能及有效性进行了科学评估.     

A flexible layered control policy for resource allocation in a sensor grid

The paper proposes a flexible layered control policy for sensor resource allocation in a sensor grid. In order to allocate sensor resources in the system to maximize the sensor grid utility, different controllers are deployed at three levels: a job-level controller, an application group controller, and a sensor grid system controller. At the lowest levels, job-level controllers perform fast, frequent, local adaptation for optimizing a single sensor grid application at a time, while, at the highest levels, sensor grid system controllers perform less frequent control actions to optimize all applications. Sensor grid system control considers all sensor grid applications in response to large system changes at coarse time granularity. Sensor grid system control exploits the interlayer coupling of the resource layer and the application layer to achieve a system-wide optimization based on the sensor grid users’ preferences. Job-level control adapts a single application to small changes at fine granularity. The layered control system uses a set of utility functions to evaluate the performance of sensor grid applications and groups. The control system chooses control actions that would result in a higher level of utility. In the simulation, a performance evaluation of the algorithm is carried out.     

基于SoRCA结构的WSN拓扑与路由优化

针对无线传感器网络SoRCA结构中存在的能耗高、负载不均衡和鲁棒性问题,提出了改进的SoRCA拓扑控制算法和路由算法。改进的拓扑控制算法根据SoRCA拓扑的结构化特点,计算出相邻传感器节点数据传输距离,然后依据传输距离调整传感器节点发射功率。改进的路由算法根据包中跳数的特征,给出数据传输时路由选择,并给出数据传输失败时新路由的选择。性能分析表明改进后的SoRCA结构较好地节省了节点的能量损耗,改善了WSN负载均衡性和鲁棒性,提高了WSN的生命周期。     

基于分簇的水声传感器网络多跳路由算法

分簇算法是指将网络分割成簇,建立多级网络,最早是由Wendi Rabiner等人在2000年提出,应用到无线传感器网络的LEACH协议中,然而分簇在水声传感器网络中的应用还存在众多弊端。为使其更好地应用到水声传感器网络中,本文将多跳引入到分簇路由协议,从网络的节能和效率角度出发,提出一种基于分簇的水声传感器网络多跳路由算法。该算法根据节点所在区域将网络划分为多个簇,每个簇创建一个子网络并创建对应的簇路由表,节点根据下一跳的状态动态修改路由,采用多跳方式传输数据,利用仿真实验的方法验证算法的优势。     

DEVSpecL: DEVS specification language for modeling,simulation and analysis of discrete event systems

Discrete EVent Systems Specification (DEVS) formalism supports specification of discrete event models in a hierarchical modular manner. This paper proposes a DEVS modeling language called DEVS Specification Language (DEVSpecL) based on which discrete event systems are modeled, simulated and analyzed within a DEVS-based framework for seamless systems design. Models specified in DEVSpecL can be translated in different forms of codes by code generators, which are executed with various tools for models verification, logical analysis, performance evaluation, and others.     

基于概率探测模型的传感器结点配置研究

无线传感器网络结点配置是传感器网络研究的核心问题之一,它反映出无线传感器网络的代价和探测能力.主要研究了基于一种更为实用化概率检测模型(引入x%-RS 的概念)的无线传感器网络覆盖优化配置问题.在严格确保无线传感器网络连通性的条件下,优化了传感器结点配置数目并达到要求的覆盖度,获得具体的传感器结点配置方案.为提高算法的效率,在分步优化算法的基础上尝试一次循环配置多个传感器结点.最后,通过模拟计算给出配置算法的性能.     

面向交通信息采集的智能无线传感器节点

为了准确实时获取交通信息参量,利用无线传感器网络技术作为智能交通感知前端和通信手段,融合GPRS技术,构建交通信息采集网,为道路交通信息采集提供了更加便捷的解决方案。设计了交通信息采集的传感器节点,提出了动态车辆探测算法和车速测量算法。实测结果表明:动态车辆探测算法和车速测量算法能够在计算能力有限的传感器节点上实现,能准确实时地获得车流量、车速等交通参量;该交通信息采集系统能满足网络大规模部署的需求,可应用于智能交通系统。     

一种无线传感器网络预分配密钥管理方案的改进

无线传感器网络在应用二元多项式密钥预分配协议时,通常容易遭受到敌方的合谋攻击。为了更好地解决这一问题,通过减少普通节点共享的密钥个数,改变簇首间建立共享密钥的方式,改进了一种无线传感器网络的密钥预分配管理方案。分析表明,改进后的方案保留了原方案的网络高安全性等优点,而且进一步节省了普通节点的内存空间,减少了节点间的通信量,延长了网络的生存周期,能够有效地抵御敌方的合谋攻击。