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231.
中远船务构筑特色安全文化的探索与实践   总被引:2,自引:2,他引:0  
本文主要阐述了在企业核心价值理念孵化牵引下生发的安全文化理念,总结和提炼了具有企业特色的“严、细、真、实、慎”的安全文化,并从制度建设、行为规范以及体现执行力的十大主要措施上,进行了比较系统的论述,对进一步促进企业安全文化建设提出了4个方面的对策。  相似文献   
232.
钢筋混凝土梁在火侵袭下的反应分析   总被引:5,自引:2,他引:5  
结构物在大火侵袭下,结构内部温度和结构挠度、内力将随时间发生不断变化,这种变化极为复杂。本文在试验研究的基础上,采用非线性有限元法,着重研究钢筋混凝土梁在火侵袭作用下其温度和挠度的反应,提出了一种理论分析方法,编制了计算机程序,对钢筋混凝土梁的温度、挠度和内力的反应进行了计算,并得到试验结果的验证。  相似文献   
233.
ABSTRACT: Electronic instruments are increasingly being used to gather water quality data. Quality assurance protocols are needed which provide adequate documentation of the procedures followed in calibration, collection, and validation of electronically acquired data. The level of precision of many data loggers exceeds the technology which is commonly used to make field measurements. Overcoming this problem involves using laboratory quality equipment in the field or enhanced quality control at the time of instrument servicing. Time control procedures for data loggers are needed to allow direct comparisons of data between instruments. Electronic instruments provide a mechanism to study transient events in great detail, but, without time controls, multiple loggers produce data which contain artifacts due to timing errors. Individual sensors deployed with data loggers are subject to different degrees of drift over time. Certain measurements can be measured with defined precision and accuracy for long periods of time, while other sensors are subject to loss of both precision and accuracy with increasing time of use. Adequate quality assurance requires the levels of precision and accuracy be documented, particularly those which vary with increasing time deployment.  相似文献   
234.
ABSTRACT: This paper discusses the economics, advantages, potential applications, and status and future research needs of porous pavements. Porous pavements are an available storm water management technique which can be used on parking lots and low volume roadways in order to reduce both storm water runoff volume and pollution. In addition, ground water recharge is enhanced. Also, cost reductions result due to elimination of curbs, drains, and small sized storm sewers. Porous asphalt pavements consist of a relatively thin course of open graded asphalt mix over a deep base of large size crushed stones. Water can be stored in the crushed stone base until it can percolate into the subbase or drain laterally. Other porous pavement types include concrete lattice blocks and a porous concrete mix.  相似文献   
235.
ABSTRACT: Sliding polynomials differ from other piecewise interpolation and smoothing methods in their functional continuity at the nodes. This functional continuity was used to establish optional spacing of nodes and optional boundary controls in data smoothing while still maintaining mathematically continuous rates or gradients. Cyclic as well as noncyclic data can be smoothed. Variance of the individual nodal values. derived through least-squares optimization, can be calculated using the rigorously determined weighting coefficients between data points and nodes. Such nodal variances are estimates of localized uncertainty in the data which complement the localization of smoothing through use of piecewise functions. Choice of controls in smoothing and calculation of variance have been incorporated in a computer program for user convenience.  相似文献   
236.
光纤Bragg光栅传感器实现斜拉桥索力实时监测的研究   总被引:6,自引:1,他引:5  
民用工程结构的健康监测 ,日益引起人们的重视 ,光纤传感技术 ,尤其是光纤光栅传感技术 ,因其易构成高性能、低成本的传感器阵列 ,并在结构监测应用工程中 ,具有巨大的潜力。笔者介绍一种斜拉桥索力实时监测的新方法即光纤光栅法。将光纤光栅刚性粘贴于传感头外表面上 ,使传感头承受拉索的索力 ,通过对光纤光栅波长移动量 (Δλb)的解调 ,以测出索力的大小。通过实验结果与理论分析证明 ,该测试系统具有结构简单、测量范围大、稳定性和线性度好等特点 ,该监测系统既可用于斜拉桥施工阶段的索力测定 ,也可以用于在役斜拉桥结构的长期安全监测。  相似文献   
237.
A multi-channel continuous water toxicity monitoring system was, after confirming the systems' performance, implemented to samples of water discharged from power plants to detect and classify their toxicity using several recombinant bioluminescent bacteria. Each channel of the system is composed of a series of two mini-bioreactors to enable a continuous operation, i.e., without system interruption due to highly toxic samples. A different recombinant bacterial strain was present in each channel: DPD2540 (fabA::lux CDABE), DPD2794 (recA::luxCDABE), and TV1061 (grpE::luxCDABE), which are induced by cell membrane-, DNA-, and protein-damaging agents, respectively. GC2 (lac::luxCDABE) is a constitutive strain, whose bioluminescence is reduced by an increase in cellular toxicity. Phenol and mitomycin C (MMC) were used for evaluating the system's performance to detect toxic chemicals. These samples were injected into the second mini-bioreactor according to a step or bell-curve manner. The field samples used in this study were obtained from the water discharged from two different power plants in Korea – from a nuclear power plant and a thermo-electronic power plant, and were injected into the second mini-bioreactor to initiate the toxicity test. Each channel showed specific bioluminescent (BL) response profiles due to the toxic compounds present in the water samples. Comparing the BL signals between the standard toxic chemical samples and discharged water samples, the equivalent toxicity of the field water could be estimated. Finally, it was proved that this novel continuous toxicity monitoring system can be used as an alternative tool for the quick monitoring and control of water quality, as well as aid in the setting up of a new monitoring strategy to protect the source of tap water and in the prevention of polluted water discharge.  相似文献   
238.
A network of five water quality monitoring stations has been established in Long Island Sound, measuring temperature, salinity, and dissolved oxygen since 1999. The stations are located in areas of extreme water quality degradation (western Long Island Sound) as well as in pristine areas (eastern Long Island Sound). The data from these stations are collected every 15 minutes and posted to the project web site in real time as provisional data. After subsequent quality assurance procedures, the data are archived to the project File Transfer Protocol (FSP) site for downloading by the user community. The network of stations is in part supported logistically by a number of partners, including state and local agencies, schools, and non-governmental organizations. Data from the monitoring programs of some of these partners are also published to the project website providing a more comprehensive and complete picture of the status of the Sound than can be provided independently. This repository of information is used by marine educators, resource managers, scientists, and the general public, each with a different end purpose. We use the data from two of the stations to show that these high frequency time series measurements can be used to complement and enhance other monitoring programs within the Sound, documenting in greater detail the occurrence and duration of hypoxic events.  相似文献   
239.
2003年陕西持续性暴雨成因分析   总被引:13,自引:8,他引:13  
张弘  孙伟 《灾害学》2004,19(3):55-61
对2003年发生在陕西的持续性暴雨分析认为: 乌山阻高与副热带高压的配置及稳定少动为这次持续性暴雨提供了有利的背景条件.贝湖低压底部分裂出小槽引导的冷空气与副高西北侧暖湿气流在高原东侧一带反复交绥是暴雨的主要成因.高低空急流耦合使高层辐散区迭加在低层辐合区的上方而产生强烈的上升运动,为深对流的发展提供了条件,促进了暴雨时中尺度系统的生成和维持.  相似文献   
240.
梁腹板开圆孔的钢框架抗震节点   总被引:11,自引:1,他引:11  
介绍了梁腹板开圆孔的钢框架梁柱节点 ,笔者探讨的基本思路是希望通过对梁截面的削弱确保结构在强震作用时的塑性铰远离节点域而出现在梁上 ;同时 ,该节点形式应用于住宅体系时 ,使水暖管线穿梁和降低结构空间占用成为可能。因此 ,笔者对该节点形式的基本受力性能及设计中需要考虑的构造措施进行了较详细的探讨 ,并利用ANSYS对其塑性区分布和剪应力分布进行了分析。研究结果初步表明 ,梁腹板开圆孔的钢框架节点具有理论上的合理性和实用上的可行性 ,可达到塑性铰外移和增加使用功能的目的。  相似文献   
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