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941.
首先介绍了USS协议及基于该协议的控制网络的结构,并重点对该控制网络的时间性能进行了分析,其中,给出了有关的测试方法,讨论了时间性能的影响以及改善时间性能的方法,最后,指出了该方法的特点及适用性。  相似文献   
942.
Air abrasion cutting, using particulates accelerated in a controlled compressed gas stream, is currently being re-evaluated as a precision tissue removal technique for dental cavity preparation. The minimal vibrations and heat generated during cutting commend the technique for use in the shaping of fragile or brittle materials that are vulnerable to vibrations and thermal stresses.
Traditional air abrasion studies have relied solely upon post-procedure imaging, and cutting process details have been inferred from the nature of the residual surface. In this paper, however, a real-time confocal microscopic imaging method is described, which for the first time has allowed prior target structure characterization with subsequent imaging of cutting interactions and substrate failure patterns. Using internally focusing long working distance Hill objective lenses, focusing deep to a protective microscope slide and adhesive interfaces, unhindered remote image sampling within the bulk of specimens such as tooth tissue, acrylic and brittle ceramics was possible.
Moreover, areas of active cutting and inactive regions were identified within air abraded cavities during their creation. The characteristics of the finished cut surfaces were demonstrated and confirmed the findings of previous SEM studies. The method allowed direct control over all the known variables influencing cutting with particulate streams.  相似文献   
943.
A computer test bench for testing and debugging natural samples of the automatic excitation regulation systems of generators, the protection units and the power part of the excitation system is described. The bench includes a personal computer with specialized input-output circuit boards for analog and digital signals, and enables the time and cost involved in developing and checking control systems to be reduced considerably. The program employed operates in real time and enables the automatic excitation regulators of synchronous generators and generators with longitudinal-transverse excitation in a specific power system to be adjusted. __________ Translated from élektricheskie Stantsii, No. 3, March 2008, pp. 47–53.  相似文献   
944.
为了减小施工中的盲目性,实现对原本隐蔽的地下灌浆工程的科学的施工控制、严格的工程质量评定和全面细致的经验总结,有必要将灌浆施工由“地下操作”变为全程“可视化操作”。即,开发一套自动跟踪记录设备,将灌浆施工过程中的压力、流量等重要参数的数值实时地记录并存储下来,同时生成这些参数的趋时曲线,从而使施工的进展情况一目了然。在此基础上,希望能进一步开发可自动同步处理数据并做出专家决策的专家系统软件,最终实现多功能的计算机自动控制的灌浆系统。  相似文献   
945.
A novel real-time scheduler was developed to implement an interactive user interface for an existing state-of-the-art, hand-held blood analyzer. A software-timer-based scheduler was designed and implemented and guaranteed schedulability analysis performed to ensure that all hard execution deadlines could be met at run time. An execution bandwidth preservation mechanism that increases the robustness and predictability of the scheduler is presented. The paper is a case study that describes the design and development process from a point of view that emphasizes the importance of the systems integration issues that were encountered.  相似文献   
946.
运行可靠性短期评估基于能量管理系统/广域测量系统(EMS/WAMS),研究电力系统在实时运行状态下的短期可靠性水平。建立了一套运行可靠性在线短期评估方案,给出了指标体系、评估算法和应用框架。进一步介绍了方案实施中所采用的关键技术:通过建立元件实时模型,评估系统在当前运行状态下的可靠性;基于瞬时状态概率评估系统的短期可靠性;采用快速排序技术进行系统状态选择,协调评估精度和速度的矛盾,实现在线评估;基于系统实时运行工况分析系统状态在预测时刻的后果。通过IEEE-RTS系统验证了整套方案的可行性和有效性。  相似文献   
947.
Update rates and fidelity in virtual environments   总被引:1,自引:0,他引:1  
Interaction is the primary characteristic of a Virtual Environment and update rate is normally taken as an index or measure of the interactivity of the system. The speed of many systems is dictated by the slowest component which is often the Computer Image Generator (CIG). It is common for the workload of the CIG to vary and hence the performance of the system. This paper shows how a variable update rate can produce undesirable results. Two solutions to this problem are presented: service degradation and worst-case. In the case of the CIG, service degradation would require the quality of the image to be reduced such that the time taken never exceeds a given deadline. The worst-case technique works by finding the longest time taken to render any view and then uses that as the deadline for completion. The support of predictive methods is one of several benefits of this approach. An implementation of the worst-case technique is described which takes finer control over the CIG than usual and may be applied to many existing systems with little modification.  相似文献   
948.
流媒体技术概述   总被引:2,自引:0,他引:2  
流媒体技术是现在最流行的技术之一,先介绍了流媒体的概念和应用流媒体技术的挑战,然后讨论了流媒体的传输方式和相关协议,最后从需求和应用的角度分析了流媒体采用的技术。  相似文献   
949.
也谈基于OWL的Windows事件驱动串行通信技术   总被引:1,自引:0,他引:1  
本结合作的实际DCS开发经经验,有针对性地就利用Windows的事件驱动进行串行通信时需要注意的问题进行了阐述。  相似文献   
950.
This paper presents an integrated real-time control system for a Robotic Filament Winding manufacturing cell. The architecture is based on a multiprocessor system employing four processor boards. The system incorporates a hierarchical control layout with the task specification at the highest level and the robot and winder set point tracking at the lowest. Eventual design goals include a PC front-end unit capable of winding path generation and testing prior to actual part production. Preliminary experimental results on cylindrical, elbow and T-shaped pipe-fittings are included.  相似文献   
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