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71.
A damage identification technique for CF/EP composite laminates using distributed piezoelectric transducers 总被引:8,自引:0,他引:8
In this study, a damage identification approach was developed for carbon fibre/epoxy composite laminates with localized internal delamination. Propagation of the Lamb wave in laminates and its interaction with the delamination were examined. The fundamental symmetric Lamb wave mode, S0, and the lowest order shear wave mode, S0′, were chosen to predict damage location. A real-time active diagnosis system was therefore established. This technique uses distributed piezoelectric transducers to generate and monitor the ultrasonic Lamb wave with narrowband frequency. The two-way switches were employed to minimize the number of transducers. A signal-processing scheme based on the time–frequency spectrographic analysis was utilised to extract useful diagnostic information. Also, an optimal identification method was applied on damage searching procedure to reduce errors and obtain the diagnostic results promptly. Experiments were conducted on [0/−45/45/90]s CF/EP laminates to verify this diagnosis system. The results obtained show that satisfactory detection accuracy could be achieved. 相似文献
72.
对水电厂计算机监控软件中的数据库管理系统进行分析研究,采取自行开发实时数据库管理系统和商用数据库管理系统相结合,并将二者紧密集成,集中管理实时数据和非实时数据,为应用软件提供了统一透明的SQL操作接口.该数据库管理方案具有快速响应、可扩充性好、使用方便等特点. 相似文献
73.
Zheng Wen Technological Faculty of Maintenance Engineering Guangzhou University Guangzhou P.R.China 《国际设备工程与管理》1997,(3)
VibrationMonitoringandDiagnosisofPipelinePumpsonOfshorePlatformsZhengWenTechnologicalFacultyofMaintenanceEngineringGuangzhou... 相似文献
74.
A vibration-acoustic method for diagnostics and monitoring of production processes such as cutting metals makes it possible
compared with other methods to reduce the requirement for measuring equipment and it provides a computer representation of
the results observed. The set of equipment suggested has low cost and it exhibits considerable flexibility compared with existing
equipment.
__________
Translated from Izmeritel’naya Tekhnika, No. 7, pp. 30–34, July, 2006. 相似文献
75.
We propose in this paper a self-organized monitoring architecture for mobile ad-hoc networks based on a selective scheme where
subsets of nodes are managed. These nodes are determined based on their network behavior in order to favor subsets of well-connected
nodes. The key idea is to relax the requirements of the management plane, and to use these manageable subsets to monitor the
performance of the overall network. We therefore propose a new performance metric to be monitored, in order to estimate the
capability of ad-hoc nodes to communicate end-to-end in the network. Extensive simulations show how different parameters affect
this metric. 相似文献
76.
77.
Carolyn McGregor Bruce Kneale Mark Tracy 《Journal of Network and Computer Applications》2007,30(4):1309-1323
Premature and ill term babies born in regional Australia must be moved to another hospital with Neonatal Intensive Care Unit (NICU) facilities. Transferred pre-term and critically ill term babies have higher mortality rates and much higher rates of long term disability than similar babies born in hospitals with NICU facilities. This paper details the Bush Babies Broadband project that aims to significantly improve the quality of treatment for babies born in rural, remote as well as urban areas by providing the first on-demand virtual NICU architecture in Australia. Real-time data collected from medical monitors and ventilators attached to the baby, audiovisual streams and static physiological data such as X-ray images are transmitted to the consulting Neonatologist to gain a better picture of the patient's condition than is currently available. The key contribution of this significant research is the infrastructure providing a mechanism for Neonatologists to receive information directly from a regional hospital, thereby preventing, in some cases, the immediate need to move the baby. A key benefit of this framework is that it is available to link regional hospitals with the supporting NICU Neonatologist ‘on demand’ eliminating the need to establish permanent point to point connections. This paper further describes the application of that architecture to a specific pilot connecting the Bathurst regional hospital with Neonatologists within the NICU at Nepean Hospital, Penrith Australia. 相似文献
78.
79.
农业重组微生物生物安全研究进展 总被引:2,自引:2,他引:0
综述了近年来农业重组微生物的研究现状和进展 ,详细介绍农业重组微生物环境释放的监控方法以及对环境的冲击作用 ,对一些有关生物安全研究的热点问题进行了探讨 相似文献
80.
分布式光纤测温系统在小湾拱坝温度监测中的运用 总被引:2,自引:1,他引:1
小湾水电工程拱坝内铺设了10 km的分布式测温光纤,为目前国内之最.本文总结了测温光纤在常态混凝土下施工埋设,特别是在当前国内没有相关技术规范的情况下,对测温光纤的率定和施工中存在的问题进行了总结.小湾大坝绘制出温度场分布图,为大坝温控工作提供了较为精准的数据依据,为今后测温光纤的推广和使用提供宝贵的经验. 相似文献