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排序方式： 共有1206条查询结果，搜索用时 15 毫秒
121.
某连续箱梁桥上部结构存在严重的病害情况,为进一步了解技术状况,通过现场检测及静、动载试验,分析病害原因,进行技术状况评价,掌握其实际承载能力,为该桥及类似病害桥梁的维修加固处理提供依据,具有一定的理论和实用价值。 相似文献
122.
在工程投标中从研究招标文件、现场考察、标价计算等方面对完成投标要注意的问题进行了论述,旨在使投标人提高中标概率和中标后的经济效益。 相似文献
123.
李淑艳 《国防交通工程与技术》2007,5(4):78-80,83
分析了国内外弯沉检测技术现状及发展动态,比较了静态弯沉量测、稳定弯沉量测及冲击荷载下动态弯沉量测等几种弯沉检测方法,详述了贝克曼梁弯沉检测与落锤式弯沉仪各自的特点与不足,最后介绍了FWD弯沉仪在工程检测中的应用实例,有利于FWD在国内的推广应用。 相似文献
124.
ABSTRACTInspections play a key role in keeping vessels safe. Inspection authorities employ different policies to decide which vessels to inspect, including type of vessel, age, and flag. Attention for vessel history is usually restricted only to past detentions. This paper demonstrates that the correlation between the probabilities of detention and (very serious and serious) incidents is very low and that proactive prevention of future incidents is improved by accounting for both risk dimensions, that is, by combining past incident and detention information for targeting high-risk vessels for inspection. Five combined methods are presented to classify vessels based on these two risk dimensions, each of which involves extensive sets of factors. These combined classification methods have predictive power for future incidents. Depending on the applied inspection rate, incorporation of incident risk improves inspection hit rates for vessels with future incidents by 30–50% compared to using only detention information. It is recommended to focus on vessels where both risks are relatively high. A practical example shows how the methods can be applied for inspection selection and for prioritizing inspection areas defined in terms of eight risk domains that include collisions, groundings, engine and hull failures, loss of life, fire, and pollution. 相似文献
125.
William S. Fisher Deborah N. Vivian Jed Campbell Charles Lobue Rebecca L. Hemmer Sherry Wilkinson 《Coastal management》2013,41(5):429-452
AbstractStates and other jurisdictions may protect coral reefs using biological water quality standards outlined by the United States Clean Water Act (CWA). Such protection will require long-term, regional monitoring of the resource using biological indicators and a probability-based sampling design. A 60-station survey targeting nearshore linear coral reef was conducted across southern Puerto Rico in December 2011 to document the status of reef inhabitants using a probabilistic, regional sampling design. The quantity, type and condition of stony corals, fish, gorgonians, and sponges were documented from each station, providing a robust representation of linear reef status and composition across the region. Fish represented 106 unique taxa and stony corals 32 unique taxa. Benthic organisms (stony corals, sponges, and gorgonians) averaged nearly 12 colonies per square meter, more than half of which were gorgonians. Assessment results can be used as a baseline to compare with future regional surveys to quantify change in reef condition over time (trend). Both temporal and spatial changes can be expected after large-scale disturbances like hurricanes Maria and Irma in 2017. The indicators and probabilistic sampling design support the long-term regional monitoring envisioned by the Environmental Protection Agency to implement CWA protections in Puerto Rico and elsewhere. 相似文献
126.
Risk-based inspection is nowadays the predominant approach to structural integrity assurance in complex engineering systems, such as those designed for and operated in deepwater environments. One of the major tasks in risk-based planning is risk ranking of the components comprising an engineering system. In this paper, a mathematical model based on data envelopment analysis is developed for this purpose, whereby two types of weights are employed: subjective judgmental weights which are provided as input, and objective which constitute the output of the model. The use of the mathematical model is illustrated in a real world system of subsea flexible pipes, which operational in the south Atlantic Shelf off the Southeast Coast of Brazil. 相似文献
127.
提出地铁列车可靠性验收的基本条件,分别介绍了基于定时截尾试验、序贯截尾试验和全数检验的3种经典的可靠性验收方法;提出基于全数检验和定时截尾试验的地铁列车整车可靠性验收方法,设计了可靠性验收的流程;以某一具体项目为例,对该可靠性验收方法进行了验证.结果 证明:基于全数检验与定时截尾试验的地铁列车整车可靠性验收方法是有效的... 相似文献
128.
129.
龙腾;王彧弋;林军;史可;潘文波;康高强 《机车电传动》2024,(1):11-21
随着感知、决策、控制、诊断等技术不断向智能化方向发展,在轨道交通领域,车载智能化应用也逐渐成为未来轨道交通发展的趋势。文章介绍了列车自动驾驶、主动防撞、基础设施检测、行为监测等车载关键技术的发展现状以及展望,这些技术的应用提高了轨道交通的运行效率和安全性。其中,列车自动驾驶技术的应用使得列车可以更加准确、高效地运行,降低了人为操作失误带来的风险;主动防撞技术的应用可以实现列车之间的自动避让,有效预防碰撞事故;基础设施检测和行为监测技术的应用可以在设备故障或者司机疲劳等情况下及时预警,减少潜在风险。随着这些技术的应用,轨道交通车载智能化将迎来更多的创新和发展,为未来轨道交通的高效、安全、智能化运营提供有力支持。 相似文献
130.