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151.
This paper reports how the study of formal logical reasoning provides insight into more everyday types of reasoning, such as that involved in language comprehension. Both of these types of cognition are thought to involve the use of mental models, and so it is reasonable to think that the cognitive operations needed for formal logical reasoning would be involved in everyday reasoning as well. We focused on three aspects of formal reasoning: (a) the integration of information into a common mental model, (b) the drawing of inferences, and (c) the coordination of alternative possibilities. We were able to show that the integration and inference components were related to narrative comprehension processes, but the coordination of alternative models was not. Thus, there is evidence for some overlap in the mental processes used in formal and everyday reasoning. This further justifies the study of formal logical reasoning as a window into certain types of everyday reasoning. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
152.
The Procedural Reasoning System (PRS) is the best established agent architecture currently available. It has been deployed in many major industrial applications, ranging from fault diagnosis on the space shuttle to air traffic management and business process control. The theory of PRS-like systems has also been widely studied: within the intelligent agents research community, the belief-desire-intention (BDI) model of practical reasoning that underpins PRS is arguably the dominant force in the theoretical foundations of rational agency. Despite the interest in PRS and BDI agents, no complete attempt has yet been made to precisely specify the behaviour of real PRS systems. This has led to the development of a range of systems that claim to conform to the PRS model, but which differ from it in many important respects. Our aim in this paper is to rectify this omission. We provide an abstract formal model of an idealised dMARS system (the most recent implementation of the PRS architecture), which precisely defines the key data structures present within the architecture and the operations that manipulate these structures. We focus in particular on dMARS plans, since these are the key tool for programming dMARS agents. The specification we present will enable other implementations of PRS to be easily developed, and will serve as a benchmark against which future architectural enhancements can be evaluated.  相似文献   
153.
154.
作为一家专业机柜生产厂商,所生产的产品主要在恶劣的环境中为电气和电子部件提供保护,有时客户会要求厂商现场协助解决一些设计和使用中碰到的问题。进行现场评估时,会经常发现基本的机柜设计并没有问题,导致问题的是一些其它因素。有时是安装不正确。例如,安装不正确的液体密封导管配件或电缆衬垫会导致灰尘或水进入机柜,幸运的是,此类问题通常在安装后不久就可发现并可快速解决。然而,对于那些需要数月或数年时间才会逐渐显现的问题怎么办?暖气炉在每个取暖季节前都会进行清洁,每3000英里汽车机油也需要更换,我们自己更是(或应该)进行例…  相似文献   
155.
Evaluating the design of flexible manufacturing systems is complex. Developing a measure of performance useful for evaluating alternate designs continues to be interesting. Here, total productivity of the system is proposed as an appropriate measure. Specification of parameters based upon strategic considerations for this measure are discussed. Finally, the usefulness of the measure is demonstrated through an example.  相似文献   
156.
Studied the differences in moral orientation in terms of gender specific modes of reasoning, in 2 experiments. In Exp 1, 32 Ss (aged 24–55 yrs) were read the "Heinz dilemma," and asked 3 questions regarding it. Deliberative and justificatory strategies were identified on the basis of the presence or absence of the higher level knowledge structures. In Exp 2, 40 undergraduates were presented with "Michael and Kohlberg Heinz dilemma," followed by a set of relevant questions. Male Ss preferred to apply a norm or rule in their solutions, while females rejected the application of a norm and sought alternative solutions. This was replicated in Exp 2, but the pattern was reversed with female Ss preferring to apply a norm. Males were divided in their use of either strategy indicating that although, genders differed in their judgments as to which norms or rules to apply; once adopted, norms and rules were used in similar ways. (French abstract) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
157.
The authors reviewed the evidential basis of three environmental approaches to reducing population obesity: What are the effects of (a) taxing or subsidizing foods, (b) manipulating the ease of food access, and (c) restricting access to certain foods? A narrative review evaluated evidence using National Heart, Lung, and Blood Institute criteria. There was strong evidence that subsidization influences food purchases, but not necessarily food consumption or body weight. Ease of food access may influence food purchases, and possibly food intake and body weight. Data on restriction were lacking. More studies are needed to justify that altering these macro-environmental variables will necessarily reduce population obesity. A proposed conceptual model posits that the steps through environmental interventions may exert intended and unintended influences on body weight and obesity prevalence. Contemplated policy changes should weigh scientific evidence with social judgments and values concerning changes to the environment. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
158.
A new image analysis technique has been developed which allows maceral analysis of coal to be carried out. The technique is able to separate the liptinite component from the background resin by using two separate images of the surface captured with different camera exposure times. At normal exposure, the liptinite has a similar grey scale value to the surrounding resin, but at a higher exposure time, the resin remains black whilst the liptinite grey scale increases significantly enough to distinguish it from the resin. The method has been tested for repeatability and reproducibility and found to be within the ISO Standard requirements.  相似文献   
159.
The constraint satisfaction problem is known to be NP-hard in general, but a number of restrictions of the problem have been identified over the years which ensure tractability. This paper introduces two simple methods of combining two or more tractable classes over disjoint domains, in order to synthesise larger, more expressive tractable classes. We demonstrate that the classes so obtained are genuinely novel, and have not been previously identified. In addition, we use algebraic techniques to extend the tractable classes which we identify, and to show that the algorithms for solving these extended classes can be less than obvious.  相似文献   
160.
Advances in instrumentation have made it possible in recent years to study the microstructure of inorganic materials at atomic resolution using the technique of high-resolution electron microscopy (HREM). Details of instrumentation have been described elsewhere [l], and applications and trends for HREM have recently been reviewed [2]. Although HREM is primarily a technique for studying bulk defects, it is increasingly also being applied in the profile-imaging mode to derive information about surfaces [3]. The high spatial resolution of the electron microscope makes it a valuable tool for the characterization of heterogeneous catalysts. This is evidenced by the growing number of studies wherein electron micrographs are being used to describe the morphology of a particular catalyst. Profile imaging is proving particularly useful in this regard for following changes in surface structure as a function of treatment conditions [4].  相似文献   
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