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11.
A fully Bayesian approach for combining multilevel failure information in fault tree quantification and optimal follow-on resource allocation 总被引:3,自引:2,他引:3
M. Hamada H. F. Martz C. S. Reese T. Graves V. Johnson A. G. Wilson 《Reliability Engineering & System Safety》2004,86(3):297-305
This paper presents a fully Bayesian approach that simultaneously combines non-overlapping (in time) basic event and higher-level event failure data in fault tree quantification. Such higher-level data often correspond to train, subsystem or system failure events. The fully Bayesian approach also automatically propagates the highest-level data to lower levels in the fault tree. A simple example illustrates our approach. The optimal allocation of resources for collecting additional data from a choice of different level events is also presented. The optimization is achieved using a genetic algorithm. 相似文献
12.
Park H Tsang T Kirk HG Ladeinde F Graves VB Spampinato PT Carroll AJ Titus PH McDonald KT 《The Review of scientific instruments》2008,79(4):045111
An optical diagnostic system is designed and constructed for imaging a free mercury jet interacting with a high intensity proton beam in a pulsed high-field solenoid magnet. The optical imaging system employs a backilluminated, laser shadow photography technique. Object illumination and image capture are transmitted through radiation-hard multimode optical fibers and flexible coherent imaging fibers. A retroreflected illumination design allows the entire passive imaging system to fit inside the bore of the solenoid magnet. A sequence of synchronized short laser light pulses are used to freeze the transient events, and the images are recorded by several high speed charge coupled devices. Quantitative and qualitative data analysis using image processing based on probability approach is described. The characteristics of free mercury jet as a high power target for beam-jet interaction at various levels of the magnetic induction field is reported in this paper. 相似文献
13.
Intra-abdominal pressure (IAP) has been used as the basis for a series of force limits for manual handling based on a limiting pressure criterion of 12 kPa (90 mm Hg). Measurements of the IAP responses to a series of standard loads were carried out on a group of eight instructors from the British coal mining industry. The results showed that there was a very low probability (.0016 or less) of obtaining an IAP value of 12 kPa or greater from the population represented by our sample. Average responses were 33% lower than would have been expected from previous reports on force limits based on IAP measurements. While more data are necessary in order to confirm the applicability of these findings to the general mining population, the results clearly suggest that greater loads could safely be lifted by mineworkers than can be lifted by the industrial population represented by the guidelines. 相似文献
14.
Li Ding Timothy Lebo John S. Erickson Dominic DiFranzo Gregory Todd Williams Xian Li James Michaelis Alvaro Graves Jin Guang Zheng Zhenning Shangguan Johanna Flores Deborah L. McGuinness James A. Hendler 《Journal of Web Semantics》2011,9(3):325-333
International open government initiatives are releasing an increasing volume of raw government datasets directly to citizens via the Web. The transparency resulting from these releases not only creates new application opportunities but also imposes new burdens inherent to large-scale distributed data integration, collaborative data manipulation and transparent data consumption. The Tetherless World Constellation (TWC) at Rensselaer Polytechnic Institute (RPI) has developed the Semantic Web-based TWC LOGD portal to support the deployment of linked open government data (LOGD). The portal is both an open source infrastructure supporting linked open government data production and consumption and a vibrant community portal that educates and serves the growing international open government community of developers, data curators and end users. This paper motivates and introduces the TWC LOGD Portal and highlights innovative aspects and lessons learned. 相似文献
15.
PulseNet standardized protocol for subtyping Listeria monocytogenes by macrorestriction and pulsed-field gel electrophoresis 总被引:4,自引:0,他引:4
PulseNet is a national network of pubic health and food regulatory laboratories established in the US to detect clusters of foodborne disease and respond quickly to foodborne outbreak investigations. PulseNet laboratories currently subtype Escherichia coli O157:H7, non-typhoidal Salmonella, and Shigella isolates by a highly standardized 1-day pulsed-field gel electrophoresis (PFGE), and exchange normalized DNA "fingerprint" patterns via the Internet. We describe a standardized molecular subtyping protocol for subtyping Listeria monocytogenes that was recently added to PulseNet. The subtyping can be completed within 30 h from the time a pure culture of the bacteria is obtained. 相似文献
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New analytical models supporting the design conceptualization of automated storage and retrieval systems are proposed. They include an analytical cycle time model for automated storage and retrieval systems using dedicated storage and computationally efficient procedures for estimating space requirements with systems using randomized or class-based storage. These models fill two gaps in the existing literature focused on analysing space and cycle time tradeoffs for alternative system configurations defined by the number of storage aisles, rows and bays. They are illustrated through a sample problem. 相似文献
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19.
The throughput performance model and the state equation model are alternative analytical approaches for determining the proportion of dual versus single command crane cycles in automated storage and retrieval systems that utilize opportunistic interleaving. The different assumptions underlying these models result in biases in the estimation of expected crane cycle times. The magnitude of the biases is investigated to assess whether the use of the older, less computationally efficient state equation model is still warranted in practical conceptualizing situations. The results suggest that the TP model is a dominating alternative for AS/RS conceptualizing applications. 相似文献
20.
Ethnic differences in social-emotional development in preschool: The impact of teacher child relationships and classroom quality. 总被引:1,自引:0,他引:1
Drawing from the National Center for Early Development and Learning (NCEDL) Multi-State Study of Prekindergarten and the State-Wide Early Education Programs Study (SWEEP), this study examined the effects of classroom and teacher variables on social-emotional development in prekindergarten. Results indicated that prekindergarten teachers rated males significantly higher in behavioral problems and lower in social competence than females. However, when teacher-child ethnic match was taken into consideration these differences were not present. In contrast to existing evidence, African American males in particular were no more likely to have teachers who report behavior problems than their Latino and White male peers. Implications for the prevention of behavioral problems are discussed. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献