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61.
We consider conditionals of the form A ? B where A depends on the future and B on the present and past. We examine models for such conditional arising in Talmudic legal cases. We call such conditionals contrary to time conditionals. Three main aspects will be investigated:
- Inverse causality from future to past, where a future condition can influence a legal event in the past (this is a man made causality).
- Comparison with similar features in modern law.
- New types of temporal logics arising from modelling the Talmudic examples.
62.
Javier Irizarry Katy L. Simonsen Dulcy M. Abraham 《Canadian Metallurgical Quarterly》2005,131(12):1310-1319
In spite of the efforts by government agencies, labor organizations, and researchers in the field of health and safety, injuries and fatalities continue to affect the construction industry. In 2002 the construction industry had the undesirable distinction of having two of the most dangerous occupations in the United States, with fatalities among structural steel workers at 58.2 per 100,000 workers (fourth highest rate) and among construction laborers at 27.7 per 100,000 workers (ninth highest rate). Costs associated with construction accidents, such as increased insurance premiums and medical expenses, and loss of productivity are also concerns in the industry. It has not been demonstrated how unsafe working conditions affect worker performance, and the impact of unsafe work practices on worker performance has not been quantified. This paper describes a methodology that included direct observation of steel erection activities and statistical analysis of task duration data. The data collected at steel erection sites included safety conditions such as the use of personal protective equipment (PPE), elevation of the work area, environmental conditions such as temperature and humidity, and worker performance in the form of task durations. Analysis of variance (ANOVA) analysis of 186 of steel erection task durations collected over a six-month period showed that the use of personal protective equipment (PPE), the time of day during which the operation was being performed, the elevation at which the work was being performed, and the presence of decking below the work area had statistically significant effects on the durations of steel erection tasks. 相似文献
63.
Kahana Michael J.; Rizzuto Daniel S.; Schneider Abraham R. 《Canadian Metallurgical Quarterly》2005,31(5):933
This article addresses the relation between item recognition and associative (cued) recall. Going beyond measures of performance on each task, the analysis focuses on the degree to which the contingency between successful recognition and successful recall of a studied item reflects the commonality of memory processes underlying the recognition and recall tasks. Specifically, 4 classes of distributed memory models are assessed for their ability to account for the relatively invariant correlation (≈ .5) between successive recognition and recall. Basic versions of each model either under- or overpredict the intertask correlation. Introducing variability in goodness-of-encoding and response criteria, as well as output encoding, enabled all 4 models to reproduce the moderate intertask correlation and the increase in correlation observed in 2 mixed-list experiments. This model-based analysis provides a general theoretical framework for interpreting contingencies between successive memory tests. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
64.
The basic operations of fuzzy sets, such as negation, intersection, and union, usually are computed by applying the one‐complement, minimum, and maximum operators to the membership functions of fuzzy sets. However, different decision agents may have different perceptions for these fuzzy operations. In this article, the concept of parameterized fuzzy operators will be introduced. A parameter α will be used to represent the degree of softness. The variance of α captures the differences of decision agents' subjective attitudes and characteristics, which result in their differing perceptions. The defined parameterized fuzzy operators also should satisfy the axiomatic requirements for the traditional fuzzy operators. A learning algorithm will be proposed to obtain the parameter α given a set of training data for each agent. In this article, the proposed parameterized fuzzy operators will be used in individual decision‐making problems. An example is given to show the concept and application of the parameterized fuzzy operators. © 2003 Wiley Periodicals, Inc. 相似文献
65.
This study considers serial production systems with exponential processing times. The systems are balanced, i.e. all resources have the same production rate capacity. Preceding the system there is a 'gate' set to regulate the flow of material into the system. A control strategy directs each resource when to work or stay idle. The trade-off is between throughput (TP) and work-in-process (WIP). G-MaxWIP is a production control strategy allowing resources, except for the gate, to work unconstrained. The gate 'shuts' once the system's WIP reaches a maximum allowable level. We study the properties of G-MaxWIP and compare it to 'simple pull' and CONWIP. Our main findings are: G-MaxWIP is superior to simple pull. For any simple pull system operating a fixed set of resources it is possible to find G-MaxWIP systems that operate the same resources with less WIP while maintaining the same (or higher) TP. G-MaxWIP is superior to CONWIP. For any CONWIP system operating a fixed set of resources it is possible to find G-MaxWIP systems that operate the same resources with less WIP while maintaining the same (or higher) TP. 相似文献
66.
Shankumar Mooyottu Anup Kollanoor-Johny Genevieve Flock Laurent Bouillaut Abhinav Upadhyay Abraham L. Sonenshein Kumar Venkitanarayanan 《International journal of molecular sciences》2014,15(3):4415-4430
Clostridium difficile is a nosocomial pathogen that causes a serious toxin-mediated enteric disease in humans. Reducing C. difficile toxin production could significantly minimize its pathogenicity and improve disease outcomes in humans. This study investigated the efficacy of two, food-grade, plant-derived compounds, namely trans-cinnamaldehyde (TC) and carvacrol (CR) in reducing C. difficile toxin production and cytotoxicity in vitro. Three hypervirulent C. difficile isolates were grown with or without the sub-inhibitory concentrations of TC or CR, and the culture supernatant and the bacterial pellet were collected for total toxin quantitation, Vero cell cytotoxicity assay and RT-qPCR analysis of toxin-encoding genes. The effect of CR and TC on a codY mutant and wild type C. difficile was also investigated. Carvacrol and TC substantially reduced C. difficile toxin production and cytotoxicity on Vero cells. The plant compounds also significantly down-regulated toxin production genes. Carvacrol and TC did not inhibit toxin production in the codY mutant of C. difficile, suggesting a potential codY-mediated anti-toxigenic mechanism of the plant compounds. The antitoxigenic concentrations of CR and TC did not inhibit the growth of beneficial gut bacteria. Our results suggest that CR and TC could potentially be used to control C. difficile, and warrant future studies in vivo. 相似文献
67.
68.
Analía V. Gómez Cristina Ferrero Cecilia Puppo Carmen C. Tadini Analía G. Abraham 《International Journal of Food Science & Technology》2014,49(10):2315-2322
The objectives of this research were to study the effect of the addition of lyophilised kefir milk to premixes for household production of bread and evaluate the quality attributes of them. Four lyophilised samples were obtained from the followings: skim milk, acidified skim milk, fermented skim milk and neutralised fermented skim milk. Breads were prepared with commercial wheat flour, lyophilised milk samples and yeast through a straight dough process. Quality was assessed through loaf volume, crumb porosity and moisture, crumb texture and crust colour. Changes in texture and starch recrystallisation by X‐ray diffractometry were determined after 1 and 3 days of storage at room temperature. Breads with acidified milks showed the highest specific volumes and crumbs with the best texture properties. Crystallinity in bread with fermented milks was higher than for skim milk sample. This would indicate that there would be a certain effect of the type of milk processing on the promotion of starch retrogradation. 相似文献
69.
Information systems (IS) research has drawn heavily on social and cognitive psychology to explain technology adoption. Indeed, the many variations of the technology acceptance model all share these same theoretical foundations. Focusing exclusively on the socio-cognitive lens can lead to overlooking enhanced explanations of technology acceptance, such that new theoretical perspectives may be warranted. In this qualitative grounded theory study, we discovered how the lens of evolutionary psychology, as embodied in the Four-Drive model, was helpful in understanding technology acceptance across three organizational sites. We contend that evolutionary psychology is an important addition to the theoretical repertoire of IS researchers, and propose including ‘evolved psychological mechanisms’ within traditional models of technology acceptance. 相似文献
70.
Abraham Kandel† 《控制论与系统》2013,44(1):119-126
Abstract A strictly binary approach to the treatment of switching circuits today is not always adequate to describe systems in the real world. This approach is partly due, to the relative simplicity of designing binary switching systems, and to the fact that basic switching modules in common use are two-positional. Consequently, every variable in Boolean logic is assumed to be two-valued. However, because of real-world constraints, the attributes of system variables are often ambiguously defined. In other words, quite often variables might have values other than falsehood and truth. Cases with such attributes arise, for example in artifical intelligence and related subjects. Ever since Zadeh introduced the idea of fuzzy set theory [11 by utilizing the concept of membership grade, a number of authors have been concerned with the analysis and applications of fuzzy models. Especially, the relation of fuzzy to switching systems have been discussed in [2]–[12] and by other researchers in relation to other topics. In this paper we are concerned with the study of fuzzy switching functions and their properties. Special attention is devoted to their minimization, enumeration, and their application to Boolean static hazard detection. 相似文献