基于多线程的小型工业实时监控数据库设计

提出了一种面向小型工业的实时监控数据库解决方案。采用ADO技术与多线程技术解决了过程监控系统中实时数据的存储、管理和处理的问题。利用Visual C＋＋6.0语言编程,在自来水厂的Ethernet现场总线设备上对监控数据库进行试验运行,其性能稳定、运行可靠。     

基于LabVIEW的便携式推力轴承数据采集系统设计

在大型水轮发电机工作中,推力轴承的运行状态与发电机工作的效率与安全有着重要的关联;因此在水轮发电机运行过程中需要对轴承系统的各项数据进行实时监测,已保证发电机在可控条件下进行作业;本系统采用了基于LabVIEW软件平台的多路并行数据采集结构,实现了对轴承系统中推力瓦的温度、油膜厚度、电机转速等试验数据的实时采集,将采集到的数据实时显示、显示界面的截屏以及对试验数据的分析、处理、记录和保存等功能;同时利用DataSocket技术实现不同计算机之间的高速数据共享,让多个试验人员实时分析记录轴承系统数据;试验结果表明此便携式推力轴承数据采集系统具有能够长时间稳定可靠的运行,数据采集控制精度高,试验人员查看数据方便,系统操作简单等特点。     

基于物联网的电梯运行安全监测软件设计与实现

电梯的实时监测是提升电梯安全监管水平的重要手段。本文介绍了基于物联网技术构建的电梯运行安全监测系统,设计了该系统客户端、监测服务器和短信服务器3个主要软件模块。该系统能实时监测电梯的运行状态,并及时将故障告警信息发送到指定的手机终端。试验表明:系统软件运行稳定可靠,报警及时有效。     

站点式飞行试验实时监控软件平台研究

飞行试验实时监控软件平台的运行效率直接影响着飞行试验过程管理的高效性。在实时数据解算服务器的基础上,配置站点服务器及DNS服务器,构建站点式飞行试验实时监控软件平台,利用交互式页面设计及网络数据库管理技术,提高实时监控软件平台的管理及维护效率,改善监控软件的用户交互模式。实现了监控组件在站点式软件平台下“访问部署、链接监控”的目的,从而简化了飞行试验监控工作环节,有助于缩短型号科目试飞周期。     

飞行试验实时监控管理系统软件设计与实现

飞行试验实时监控是飞机试飞的重要环节, 监控大厅是实施实时监控的重要场所。为了提升飞行监控大厅实时监控效能,我们自行研发管理软件,通过软件相关技术实现了飞机相关实时监控资源管理、网络负载与局域网管理、安全机制、SD-LAN技术研制与应用。通过此软件也解决了传统纸质化管理方式约束力差以及监控人员对个人监控职责不清楚而无目标监控的问题,另外由于监控人员经常来自国内不同的单位,指挥员在监控过程中遇到问题很难及时落实到具体监控人员,采用此软件后指挥员可以实时查询当前型号飞机各个专业监控人员的情况,并及时与之沟通交流,更好的完成试飞任务。本系统通过一段时间运行,各项技术指标达到预期目的,实时监控管理、网络管控系统等并行运行稳定、清晰。     

动力系统的智能化监测与安全保护设计

直升机旋翼模型风洞试验是高转速、高风险的动态试验,为保护试验的安全运行,必须实时、准确、可靠地监测试验台关键驱动设备-动力驱动系统及辅助系统的运行状态,并根据运行状态分级采取相应的保护措施。本文以动力系统主控PLC为基础,打通试验台各系统之间的信息孤岛,提出了一种基于历史数据分析的设备运行状态分级评价及风险评估方法,根据实时运行数据判断动力系统运行风险,给出安全操作建议。风洞试验应用效果表明本文构建的旋翼模型试验台动力系统智能监测与安全保护设计数据分析科学,状态监测实时,安全保护可靠。提高了直升机试验的安全可靠性。     

直升机旋翼平衡实时调整地面维护处理系统设计与实现

为了开展直升机旋翼实时调整技术(In-Flight Tuning, IFT)研究和产品研制,开发了一套地面维护处理系统。它具有工作流程控制、数据采集与监测、在线实时调整、数据分析和健康监测功能。同时针对飞行系统数据传输稳定性、多种独立的业务数据同步问题,设计了一种基于时间的业务数据同步方法,并采用多线程技术优化数据处理。经旋翼塔试验验证,本系统软件运行稳定,实时调整方法能够有效降低旋翼系统振动。     

智能车无线监控与定位系统

为实时掌控智能车的运行参数和定位参数,设计了智能车无线监控与定位系统。该系统包括智能车系统、监控系统和定位系统。实验表明,利用通信技术和Zigbee技术能够实时获取智能车的运行参数和控制智能车的运行状态,并能够进行准确定位。     

全机结构强度试验多路故障监测系统设计及应用

在全尺寸飞机结构强度试验中,实时监控飞机姿态及加载系统运行状态尤为重要。针对现有的多路故障检测装置电路复杂、功能单一及通用性差等缺陷,本文提出了一种试验安全信号分类监测及保护技术,并设计了一套基于PLC的全机结构强度试验分级多路故障监测系统,可实现对试验运行过程中的多路安全信号的实时监测、逻辑运算以及分级响应。该智能监测系统已成功应用在全机结构强度试验中,对保护试验件及提升试验效率具有重要意义。     

基于物联网的氙灯老化试验辅助系统

针对氙灯老化试验,利用物联网技术设计了一套试验辅助系统。辅助系统实现了氙灯老化箱的运行状态、温度、湿度、光照等重要参数的实时采集以及可视化展示。试验人员能够远程实时获取设备信息,接收辅助系统提供的样件进度信息、报警信息,并根据辅助系统进行氙灯光源的维护保养,帮助试验人员及时有效地获取试验过程信息,大大提高试验效率。     

Model-based software diagnosis

Software development is a complex process in which it is all too easy to introduce errors or faults that can be extremely difficult to identify . However , there has been little research into the use of intelligent diagnostic techniques for software ( as compared to hardware , for example ). Therefore , applying such techniques to software is potentially extremely useful . In many cases the presence of a bug is only identified when an invalid result is observed . However , the task of identifying the software elements that may have contributed to this result can be a time - consuming and tedious task , but must be performed before the actual root cause can be identified and a repair effected . This operation is akin to fault localization within hardware diagnosis and has been the subject of extensive research within the model - based community . This article presents a technique that minimizes the tedious task of fault localization with the software system , leaving the developer to concentrate on identifying the root cause and remedial action . In particular , we treat diagnosis as a trial with witnesses for the prosecution and defense . The result is a diagnostic trial that uses the source code of a system as its model and knowledge of valid and invalid results ( victims ) to identify a set of suspects for a developer to investigate further .     

基于浮标平台的海洋生物化学要素原位监测仪器研制与近海实验研究

海洋生物化学要素是海洋环境与生态监测的重要对象。传统的监测方法多基于人工操作,需 要使用化学试剂,不仅测量时间长,而且无法及时准确反映海水的当前状态。该文基于光学传感的方 法,研究无需化学试剂的海洋叶绿素 a、化学需氧量(COD)、生化需氧量(BOD)原位传感器和水下浮 游生物成像仪,并基于浮标平台在近海开展了海洋原位测量实验和示范。在海试过程中,通过采用环 境友好的生物涂料和机械刷设计,克服了生物附着对传感器连续工作的影响,实现了传感器连续原位 工作 6 个月以上,实验结果准确反映了海水的真实状态。     

集成用户可定制锁和操作转换的并发控制方法

锁是一种用于分布计算和数据库系统的传统的并发控制方法,它通过将对共享对象的修改访问权在某一时间内授予唯一的访问者,以使对共享对象的访问得以串行化;操作转换方法是一种用于实时协同系统中一致性维护的方法。这两种方法均不能完全解决数据一致性问题。论述了锁机制和操作转换在一致性维护中的互补关系,提出了一种用户可定制的锁方法,并将该锁方法与操作转换结合起来应用于全复制式的协同环境中。用户可定制的锁机制集成操作转换方法具有可靠性高、响应速度快和非阻塞的特点;用户动态定制加锁粒度可以保证最大程度的并发性。该方法有效地解决了实时群件系统中一般的一致性问题和特定上下文的一致性问题。     

基于连续分区与串联编码的线段裁剪新算法

提出连续分区裁剪的新思想,按不同的方式多次将平面分成不同的区域,从而简单而快速地舍弃窗外线段,避免没有必要的求交运算。2次分区后提出串联编码技术,将2次编码技术中的两次编码串联起来,继承了第1次编码所做的工作,节省了很多时间;在此基础上,3次分区中提出点对称技术,并将其应用于多次分区,取得了较好的效果。点对称技术所划分平面区域边界的斜率为0°、±45°或无穷大,适合于程序的实现,且与2次编码技术相比,可以舍弃更多的窗外线段,避免更多的求交运算。算法实现清楚地表明该算法能明显提高线段裁剪效率。     

基于主体的扩展权能技术研究与实现

权能作为一种基于主体的访问控制手段,其实现方式灵活多样,使用方便。权能的概念很早就已经提出,已经成为分布式操作系统中的一种基本访问控制机制。通过对主体行为的限制,权能技术能方便地达到限制主体作用范围的目的。另外,通过对传统权能技术进行改进,还可同时实现对访问时间和次数的限制。在此基础上,通过对操作系统中权能实现方法的研究,提出了扩展权能访问控制（Extended Capability Access Control,ECAC）,并给出了该技术在Irix系统上的一种实现方法。     

Fast modular multiplication based on complement representation and canonical recoding

Modular multiplication is the fundamental operation in implementing circuits for cryptosystem, as the process of encrypting and decrypting a message requires modular exponentiation that can be decomposed into multiplications. In this paper, a proposed multiplication method utilizes the complement recoding method and canonical recoding technique. By performing the complement representation method and canonical recoding technique, the number of partial products can be further reduced. Based on these techniques, an algorithm with efficient multiplication method is proposed. For multiplication operation, in average case, the proposed algorithm can reduce the number of k-bit additions from 1/4k+(log (k)/k)+5/2 to 1/6k+(log (k)/k)+5/2, where k is the bit length of the multiplicand and multiplier. Besides, if we perform the proposed technique to compute common-multiplicand multiplication, the computational complexity can reduce the number of k-bit additions from 1/2k+2×(log (k)/k)+5 to 1/3k+2×(log (k)/k)+5. We can, therefore, efficiently speed up the overall computing performance of the multiplication operation.     

Estimating Effective Prefetch Distance in Threaded Prefetching for Linked Data Structures

Helper threaded prefetching based on chip multiprocessor has been shown to reduce memory latency and improve overall system performance, and has been explored in linked data structures accesses. In our earlier work, we had proposed an effective threaded prefetching technique that balances delinquent loads between main thread and helper thread to improve effectiveness of prefetching. In this paper, we analyze memory access characteristic of specific application to estimate effective prefetch distance range for our proposed threaded prefetching technique. The effect of hardware prefetchers on the estimation is also exploited. We discuss key design issues of our proposed method and present preliminary experimental results. Our experimental evaluations indicated that the bounded range of effective prefetch distance can be determined using our method, and the optimal prefetch distances can be determined based on the estimated effective prefetch distance range by few trial runs.     

An approach to surface retouching and mesh smoothing

In this paper, we discuss a novel, fast, practical algorithm for surface modification of geometric objects. A space-mapping technique is used to transform a given or damaged part of a surface into a different shape in a continuous manner. The proposed approach is used for surface-retouching and mesh-smoothing problems. The technique, in fact, is based on a local processing of polygonal data that can be applied to the fairing of 3D meshes. We consider shape transformation as a general type of operation for surface modification and attempt to approach the problem from a single point of view, namely, that of the space-mapping technique based on the implementation of radial-basis functions. Experimental results are included to demonstrate the functionality of our mesh-modeling tool.     

医学图象软组织分层显示的设计与实现

主要针对医学图象提出了基于距离变换的算法,并应用在我们自行开发的三维医学图象处理与分析系统中对医学CT图象进行软组织分层显示处理,取得了较好的分割效果。应用该算法由于能够达到物体外轮廓的准确识别和切割深度的精确定位,从而使其重建后的三维体显示模型可清晰地再现皮下血管肌肉与周围组织的解剖关系,大大增强了医学图象分析系统的临床实用价值。     

Adaptive learning control for general nonlinear systems with nonuniform trial lengths,initial state deviation,and unknown control direction

This paper studies the iteration varying trail lengths problem for high‐order continuous‐time nonlinear systems, where the initial state may deviate from the desired value and the sign of input gain is unknown. First, to deal with the general nonlinear systems, a fuzzy approximation technique is applied for each dimension of the nonlinear function and the backstepping technique is then used for controller design and performance analysis. Moreover, to deal with the randomly varying trial length problem, we introduce a novel composite energy function for the asymptotic convergence analysis. Furthermore, the initial state deviation issue is resolved by introducing an initial state learning protocol such that the initial state tracking error converges to zero asymptotically. Last but not least, the unknown control direction is regulated by applying a Nussbaum function and the analysis in the presence of nonuniform trial lengths is strictly established. Based on these treatments, we prove that the tracking error converges to zero as iteration number increases and all signals are bounded. The effectiveness of the proposed framework is verified by numerical simulations.