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1.
This paper presents Bayes estimators for the reliability measures of the individual components in a multi-component systems in the presence of masked system life test data. The life time distributions of the system components are assumed to be geometric with different parameters. Two-sided Bayesian probability intervals of the parameters are also derived. Numerical simulation study is given in order to: (i) explain how one can apply the theoretical results obtained, (ii) study the influence of the sample size and masking level on the accuracy of point estimates. 相似文献
2.
当前,市场上数据库系统软件种类非常多,Access是Microsoft旗下的一款小型数据库系统软件,其特点是使用简便、体积较小,非常适合于信息量较少的数据信息管理。在Access的使用过程当中,我们必须要考虑到的一个问题就是数据库的安全问题,为了能够保证Access数据库数据信息的安全性与完整性,就必须要采取有效的安全策略来对Access数据库进行保护。基于作者自身的实际工作经验与相关知识了解,首先对Access数据库软件系统的安全定义与安全风险进行了分析,然后针对性地提出了部分安全策略,以期对Access数据库的安全质量起到提升作用。 相似文献
3.
针对房地产投资周期长、金额大、变现能力差的特点,以房地产项目开发前期为分析对象,将可拓工程方法引入到房地产风险分析评价中,构建房地产项目开发前期风险的可拓评判模型,并通过具体实例验证了这种方法的可行性. 相似文献
4.
Soil effects due to sewage sludge application in agriculture 总被引:3,自引:0,他引:3
Field trials show that increased nutrients (mainly P) and heavy metals in soil due to agricultural use of sewage sludge have mainly to be expected when sludge is applied in too high amounts. The biological effects of heavy metals on plants are determined by their solubility which is increased by pH decrease and degradation of organic matter. Normally, it should be expected that the microbial activity in soil would increase with the application of organic matter in sewage sludge. But, also negative effects on the microflora by simultaneous enrichment of organic matter or inorganic and organic pollutants were found. The most important deleterious effects on soil microorganisms are the reduction in size of the total biomass, a reduced nitrogen fixing activity and changes in the composition of microbial populations of the soil. At what stage heavy metal toxicity to soil microorganisms or to microbial processes in soil is likely to become evident is unfortunately still uncertain. Again, the soluble fraction of heavy metals (also of organic pollutants) is a determing factor. To minimize the shown environmental risks an adequate sludge management is proposed. 相似文献
5.
成永康 《重庆电力高等专科学校学报》2014,(6):28-30
分析高职院校廉政建设的现状及存在的问题,运用管理反腐的理念,对如何开展廉政风险防控机制建设进行探讨。 相似文献
6.
基于资源分布规律的信息系统风险量化模型 总被引:1,自引:1,他引:0
为了实施信息系统的风险度量,首先基于信息流的资源分布规律,参考风险评估要素改进模型,得到具有体系性和完整性的风险分布;在获取风险分布后,基于资源保护角度,考虑安全保护等级,运用层次分析法、多级模糊综合评判、函数级数展开、F-统计量等方法和工具对资源的安全属性所面临的风险进行量化,给出系统的风险量化指标体系,重点考虑风险之间的相关性,构建相关性准则,并得到其计算量为o(Si)。 相似文献
7.
Michael J. Griffin 《Ergonomics》2015,58(7):1063-1070
At work or in leisure activities, many people are exposed to vibration or mechanical shocks associated with risks of injury or disease. This paper identifies information that can be used to decide whether there may be a risk from exposure to hand-transmitted vibration or whole-body vibration and shock, and suggests actions that can control the risks. The complex and time-varying nature of human exposures to vibration and shock, the complexity of the different disorders and uncertainty as to the mechanisms of injury and the factors influencing injury have prevented the definition of dose–response relationships well proven by scientific study. It is necessary to wave a flag indicating when there is a need to control risks from exposure to vibration and shock while scientific enquiry provides understanding needed to weave a better flag. It is concluded that quantifying exposure severity is often neither necessary nor sufficient to either identify risks or implement measures that control the risks.Practitioner Summary: The identification of risks associated with exposure to vibration and mechanical shock cannot, and need not, rely solely on the quantification of exposure severity. Qualitative methods can provide a sufficient indication of the need for control measures, which should not be restricted to reducing standardised measures of exposure severity. 相似文献
8.
电力设备的诊断与维护在电力系统的运行中起着非常重要的作用。本文着重介绍利用信息、智能控制、网络等技术构建基于互联网的电力设备网络管理系统,为电力设备的诊断与维护提供一个方便的讨论、共享及全球合作的技术平台。 相似文献
9.
本文简单阐述了目前电子商务中普遍存在的安全隐患,结合电子商务的主要安全要素,提出几点解决方案。 相似文献
10.
Vicente G. CanchoFranscisco Louzada-Neto Gladys D.C. Barriga 《Computational statistics & data analysis》2011,55(1):677-686
In this paper we proposed a new two-parameters lifetime distribution with increasing failure rate. The new distribution arises on a latent complementary risk problem base. The properties of the proposed distribution are discussed, including a formal proof of its probability density function and explicit algebraic formulae for its reliability and failure rate functions, quantiles and moments, including the mean and variance. A simple EM-type algorithm for iteratively computing maximum likelihood estimates is presented. The Fisher information matrix is derived analytically in order to obtaining the asymptotic covariance matrix. The methodology is illustrated on a real data set. 相似文献