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941.
Hui Jin Mary Ann LundteigenMarvin Rausand 《Reliability Engineering & System Safety》2011,96(3):365-373
Safety instrumented systems (SISs) are usually divided into two modes of operation, low-demand and high-demand. Unfortunately, this classification is not easy to justify and the available formulas that are used to quantify the reliability performance in these two modes of operation are unable to capture combined effects of functional testing, spurious activations, and successful responses to demands. This article discusses some important modeling issues for SIS reliability performance quantification, and demonstrates their implementation in a Markov model. The accuracy of the Markov model for a simple case study of a pressure transmitter is verified through comparison with a scenario-based formula, and it is shown that the Markov approach gives a sufficiently accurate result for all demand rates, covering both low- and high-demand modes of operation. 相似文献
942.
Eric W.T. Ngai Dorothy C.K. Chau T.L.A. Chan 《The Journal of Strategic Information Systems》2011,20(3):232-249
Given the growing emphasis on the need for supply chain agility to sustain competitive advantage, this study explores the impact of the relationship between supply chain competence and supply chain agility on firm performance. Although the influence of supply chain agility on firm performance has been acknowledged, this study further articulates the relationship from the perspective of inter-organizational collaboration. We develop a conceptual model based on the resource-based view and employ a multi-case study method in this exploratory research. Our findings highlight the importance of distinguishing the difference between supply chain agility and supply chain competence and their impact on firm performance. This study contributes to the growing body of conceptual and empirical literature on supply chain agility and adds to the understanding of the complexity of supply chain competence. 相似文献
943.
本文以国密算法CPU卡为核心,详细阐述了基于国密CPU卡的门禁管理系统的设计,并以佛山市文化中心为例,分析了国密CPU卡门禁在项目中的应用情况。 相似文献
944.
U. Götze Th. Weber C. Linke A. Schmidt 《Materialwissenschaft und Werkstofftechnik》2009,40(7):566-572
Target Costing for Materials – Potentialities and Methodology Target Costing is a standard instrument of cost management in business administration, but hardly mentioned in the economic oriented literature on material sciences. Nevertheless there are high potentialities for developers, producers, or users of materials regarding the improvement of efficiency. Therefore, this article will present these potentialities of a material oriented Target Costing. Besides, the general methodology of Target Costing will be modified to meet the specifics of materials from the perspectives of users of materials on the one hand and developers respectively producers of materials on the other. 相似文献
945.
We consider the basic delay-time model in which a system has three states, the perfect functioning state, a defective state and the failure state. The system is deteriorating and to reduce the number of failures, preventive replacements are carried out when the system is in the defective state. The time in the defective state is referred to as the delay time. Inspections are required to check whether the system is in the defective state. System failures are safety critical and to control the risk, management considers two types of safety constraints: (i) the probability of at least one failure in the interval [0,A] should not exceed a fixed probability ω1 and (ii) the fraction of time the system is in the defective state should not exceed a fixed limit ω2. The problem is to determine optimal inspection intervals T, minimizing the expected discounted costs under the safety constraints. Conditions are established for when the safety constraints affect the optimal inspection time and causes increased costs. 相似文献
946.
A GIS Database for Sustainable Management of Shallow Water Resources in the Tulul al Ashaqif Region, NE Jordan 总被引:2,自引:2,他引:0
The Tulul al Ashaqif region is an arid area in northeastern Jordan that contains renewable shallow perched aquifer water.
The study of these aquifers has led to better understanding of the recharge process as well as other hydrological issues related
to management of water resources in similar areas. The use of geographic information system (GIS)-based predictive mapping
to locate areas of high potential for shallow perched aquifer sites is explored in this paper. Knowledge of the hydrologic,
geologic and geomorphic variables influencing the development of shallow aquifer formation is used to produce GIS layers representing
the spatial distribution of those variables. The GIS layers are then analyzed to identify locations where combinations of
environmental variables match patterns observed at known sites. In addition, information can be deduced on the volume of water
that is available and the best locations to site recharge facilities. Moreover, future development of these resources requires
consideration of possible adverse affects of usage on these resources. The database developed can be used for this purpose
as well. 相似文献
947.
项目管理作为带有强执行文化色彩的管理工具,为提高企业的执行力提供了可操作性强、规范的快速通道.在有完善知识体系指导下的项目管理实践活动不但可以有效地解决企业执行力差的问题,而且能够在企业中建立起行之有效的执行体系,并最终帮助企业形成执行文化,从而提升企业的竞争力. 相似文献
948.
Lars Peter Andersen Line Nørdam Thomas Joensson Pete Kines Kent J. Nielsen 《Construction Management & Economics》2018,36(1):22-31
The construction industry has one of the highest frequencies of work-related accidents. We examined whether construction workers predominantly identify themselves in terms of their workgroup or in terms of the construction site. In addition, we examined the associations between social identity and safety climate, and how these constructs are associated with work-related accidents. The analyses were based on questionnaire responses from 478 construction workers from two large construction sites, and the methods involved structural equation modeling. Results showed that the workers identified themselves primarily with their workgroup, and to a lesser degree with the construction site. Social identity and safety climate were related both at the workgroup and construction site levels, meaning that social identity may be an antecedent for safety climate. The association between social identity and safety climate was stronger at the workgroup level than at the construction site level. Finally, safety climate at both levels was inversely associated with self-reported accidents, with the strongest association at the workgroup level. A focus on improving safety climate, particularly by integrating initiatives at both the workgroup and management level, may have the potential to improve safety performance and thus decrease the risk of accidents and injuries on construction sites. 相似文献
949.
《Thin》2015
A two-part paper has been written to summarise the main results of a comparative study on the design provisions currently adopted in Europe (EU) and the United States (US) for steel storage pallet racks. In part 1 (Discussion and general comparisons), key features of the verification procedures for thin-walled cold-formed members as well as of the design alternatives permitted by the EU and US rack codes have been discussed, pointing out the most relevant similarities and differences. The present part 2 applies six design alternatives to medium-rise pallet racks unbraced in the longitudinal direction. In particular, the proposed research outcomes are based on the design of 216 racks differing for configurations, geometry of components and degree of rotational stiffness of beam-to-column joints and base-plate connections. Results are presented and compared directly to each other in term of safety index in order to allow for a concrete appraisal of the most relevant differences between the considered design methods, highlighting also the influence associated with the approaches to modelling the geometric imperfection effects. Finally, Appendix A presents a complete design example to be used as benchmark for researchers and designers, where all the discussed design options are applied. 相似文献
950.
《Food Control》2016
Food Fraud is illegal deception for economic gain using food. There are many types of fraud including adulterant-substances, tampering, theft, diversion and gray marketing, simulations, misbranded, and intellectual property rights product counterfeiting. The concept is beginning to be addressed by laws, regulations, standards, and certifications. Regardless of the presence of an actual health hazard, Food Fraud incidents can: negatively impact sales, brand equity, market capitalization; violate regulations such as Sarbanes-Oxley; and even lead to the criminal prosecution of corporate leaders. Emerging regulations and industry standards are requiring risk and vulnerability assessments of Food Fraud as a prerequisite to countermeasures and decision-making systems. These assessments and risk management systems are not familiar food safety tools. It is effective and efficient to utilize an enterprise risk management (ERM) framework, such as developed by the Committee of the Sponsoring Companies of the Treadway Commission (COSO). ERM risk assessment occurs into two stages: (1) a qualitative initial screening followed by (2) a more detailed quantitative assessment. All types of Food Fraud can result in enterprise-wide risks so an enterprise risk management system must cover all types of vulnerabilities. The model developed in this paper addresses the unmet need of the first stage referred to here as the Food Fraud Initial Screening (FFIS). 相似文献