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Software plays an increasingly important role in modern safety-critical systems. Although, research has been done to integrate software into the classical probabilistic risk assessment (PRA) framework, current PRA practice overwhelmingly neglects the contribution of software to system risk. Dynamic probabilistic risk assessment (DPRA) is considered to be the next generation of PRA techniques. DPRA is a set of methods and techniques in which simulation models that represent the behavior of the elements of a system are exercised in order to identify risks and vulnerabilities of the system. The fact remains, however, that modeling software for use in the DPRA framework is also quite complex and very little has been done to address the question directly and comprehensively. This paper develops a methodology to integrate software contributions in the DPRA environment. The framework includes a software representation, and an approach to incorporate the software representation into the DPRA environment SimPRA. The software representation is based on multi-level objects and the paper also proposes a framework to simulate the multi-level objects in the simulation-based DPRA environment. This is a new methodology to address the state explosion problem in the DPRA environment. This study is the first systematic effort to integrate software risk contributions into DPRA environments. 相似文献
3.
Review: Modified Atmosphere Packaging and its effects on the microbiological quality and safety of produce 总被引:10,自引:0,他引:10
Carol A. Phillips 《International Journal of Food Science & Technology》1996,31(6):463-479
Modified Atmosphere Packaging and related technologies are increasingly used to extend shelf-life of fresh produce. This paper reviews the effect of such technology on the spoilage microbiological flora and food-borne pathogens which may be present in produce and also on the organoleptic properties of the product. 相似文献
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Rubichi Sandro; Nicoletti Roberto; Iani Cristina; Umiltà Carol 《Canadian Metallurgical Quarterly》1997,23(5):1353
We investigated whether the Simon effect depends on the orienting of attention. In Experiment 1, participants were required to execute left-right discriminative responses to 2 patterns that were presented to the left or right of fixation. The 2 patterns were similar, and the discrimination was difficult. A letter at fixation signaled whether the current trial was a catch trial. The results showed a reversal of the Simon effect. That is, spatially noncorresponding responses were faster than spatially corresponding responses. In Experiment 2, the discrimination of the relevant stimulus attribute was easy. In Experiment 3, the discrimination of the relevant stimulus attribute was difficult, but the stimulus exposure time was long. In either experiment, the regular Simon effect was reinstated. In Experiment 4, the letter that signaled a catch trial appeared to the left or right of the imperative stimulus. The Simon effect occurred relative to the position of the letter. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
6.
Gabriel Tsechpenakis Dimitris Metaxas Carol Neidle 《Computer Vision and Image Understanding》2006,104(2-3):140
We present a data-driven dynamic coupling between discrete and continuous methods for tracking objects of high dofs, which overcomes the limitations of previous techniques. In our approach, two trackers work in parallel, and the coupling between them is based on the tracking error. We use a model-based continuous method to achieve accurate results and, in cases of failure, we re-initialize the model using our discrete tracker. This method maintains the accuracy of a more tightly coupled system, while increasing its efficiency. At any given frame, our discrete tracker uses the current and several previous frames to search into a database for the best matching solution. For improved robustness, object configuration sequences, rather than single configurations, are stored in the database. We apply our framework to the problem of 3D hand tracking from image sequences and the discrimination between fingerspelling and continuous signs in American Sign Language. 相似文献
7.
The addition of controlled amounts of phosphorus to 2 1/4Cr-1 Mo steel, heat treated under two different conditions, has produced microstructures containing a wide spectrum of types and amounts of individual carbide phases. X-ray diffraction analysis of carbide precipitates has been undertaken following quantitative extraction by anodic dissolution of the matrix. By combining this with selective chemical dissolution of certain carbide types, calibrations of relative weight fractions against the intensities of suitable X-ray diffraction peaks may be obtained without the need for the addition of a standard calibration powder. This has allowed the determination of the absolute amounts, within a given steel sample, of the carbide types M6C, M7C3, M23C6 and, most importantly, the creep-strengthening M2X phase. 相似文献
8.
Self-disclosure plays a central role in the development and maintenance of relationships. One way that researchers have explored these processes is by studying the links between self-disclosure and liking. Using meta-analytic procedures, the present work sought to clarify and review this literature by evaluating the evidence for 3 distinct disclosure-liking effects. Significant disclosure-liking relations were found for each effect: (1) People who engage in intimate disclosures tend to be liked more than people who disclose at lower levels, (2) people disclose more to those whom they initially like, and (3) people like others as a result of having disclosed to them. In addition, the relation between disclosure and liking was moderated by a number of variables, including study paradigm, type of disclosure, and gender of the discloser. Taken together, these results suggest that various disclosure-liking effects can be integrated and viewed as operating together within a dynamic interpersonal system. Implications for theory development are discussed, and avenues for future research are suggested. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
9.
Bloody Shankbones and Braided Bread: The Food Voice and the Fashioning of American Jewish Identities
Carol Harris-Shapiro 《Food and Foodways: Explorations in the History and Culture of》2006,14(2):67-90
American Jewish consensus on what constitutes a “good Jew” has faded in recent decades in the wake of American trends of declining communal authority and increasing emphasis on individual fashioning of religious and ethnic identities. Sociologists of American Jewry have begun to look at everyday activities to discover new configurations of Jewish belief and practice. In this study, food narratives are shown to be an important site for both the articulation and authentication of atypical Jewish identities. Two women respondents, taken from a larger interview study of American Jewry, use food stories as a vehicle to reject standards of proper Jewish attitudes and behavior and justify their differences from the norm. This study suggests that American Jewish foodways, usually studied as evidence of American acculturation or Jewish nostalgia, can also be fruitfully examined to better understand personalized Jewish identities. 相似文献
10.
A social-cognitive approach to motivation and personality. 总被引:9,自引:0,他引:9
Past work has documented and described major patterns of adaptive and maladaptive behavior: the mastery-oriented and the helpless patterns. In this article, we present a research-based model that accounts for these patterns in terms of underlying psychological processes. The model specifies how individuals' implicit theories orient them toward particular goals and how these goals set up the different patterns. Indeed, we show how each feature (cognitive, affective, and behavioral) of the adaptive and maladaptive patterns can be seen to follow directly from different goals. We then examine the generality of the model and use it to illuminate phenomena in a wide variety of domains. Finally, we place the model in its broadest context and examine its implications for our understanding of motivational and personality processes. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献