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991.
Four experiments examined how people make inductive inferences using categories. Subjects read stories in which 2 categories were mentioned as possible identities of an object. The less likely category was varied to determine if people were using it, as well as the most likely category, in making predictions about the object. Experiment 1 showed that even when categorization uncertainty was emphasized, subjects used only 1 category as the basis for their prediction. Experiments 2–4 examined whether people would use multiple categories for making predictions when the feature to be predicted was associated to the less likely category. Multiple categories were used in this case, but only in limited circumstances; furthermore, using multiple categories in 1 prediction did not cause subjects to use them for subsequent predictions. The results increase the understanding of how categories are used in inductive inference. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
992.
Davis Roger T.; Blashfield Roger K.; McElroy Ross A. 《Canadian Metallurgical Quarterly》1993,102(2):319
Focused on how clinicians combine symptom information about narcissistic personality disorder (NPD) to make a diagnosis. A sample of 59 psychiatrists and clinical psychologists were asked to read and diagnose 20 case histories of which 6 cases had criteria for NPD embedded as sentences. The number of criteria and the face validity of the criteria were varied across case histories. Three models of how criteria might be combined to form a diagnosis were compared: the polythetic model, the additive model, and the weighting model. The results were most consistent with the weighting model. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
993.
994.
The development of new wind energy projects requires a significant consideration of land use issues. An analytic framework using a Geographic Information System (GIS) was developed to evaluate site suitability for wind turbines and to predict the locations and extent of land available for feasible wind power development. The framework uses rule-based spatial analysis to evaluate different scenarios. The suitability criteria include physical requirements as well as environmental and human impact factors. By including socio-political concerns, this technique can assist in forecasting the acceptance level of wind farms by the public. The analysis was used to evaluate the nine-county region of the Greater San Francisco Bay Area. The model accurately depicts areas where large-scale wind farms have been developed or proposed. It also shows that there are many locations available in the Bay Area for the placement of smaller-scale wind turbines. The framework has application to other regions where future wind farm development is proposed. This information can be used by energy planners to predict the extent that wind energy can be developed based on land availability and public perception. 相似文献
995.
Norma C. Pangilinan G. Wayne Ivie Beverly A. Clement Ross C. Beier Michael Uwayjan 《Journal of chemical ecology》1992,18(2):253-270
The metabolism of xanthotoxin, a naturally occurring furanocoumarin photosensitizer, was studied in laying hens and a lactating goat treated with single oral doses equivalent to 10 mg xanthotoxin/kg of body weight. Within 48 h, essentially all of the administered radiocarbon was eliminated in the excreta of the laying hens, while in the goat 92% and 3% were excreted in the urine and feces, respectively. Radiocarbon residues in the milk, egg white, and egg yolk were low. Xanthotoxin, 8-hydroxypsoralen (xanthotoxol), 6-(7-hydroxy-8-methoxycoumaryl)-acetic acid (HCA) and 6-(7-hydroxy-8-methoxycoumaryl)-hydroxyacetic acid (HCHA) were identified in the excreta of laying hens. In the goat, xanthotoxin was metabolized to HCA, HCHA, xanthotoxol, 5,8-dihydroxypsoralen, psoralenquinone, 5-hydroxy-8-methoxy-psoralen and 3[5-(6-hydroxy-7-methoxybenzofuryl)]-propanoic acid. Thus, identified metabolites in one or both of these species arose throughO-demethylation, oxidative cleavage of the furan ring, hydroxylation, reduction, oxidation, and hydrolysis of the lactone ring. 相似文献
996.
Insoo Woo Sung Ye Kim Ross Maciejewski David S. Ebert Timothy D. Ropp Krystal Thomas 《Computer Graphics Forum》2009,28(3):943-950
When performing daily maintenance and repair tasks, technicians require access to a variety of technical diagrams. As technicians trace components and diagrams from page-to-page, within and across manuals, the contextual information of the components they are analyzing can easily be lost. To overcome these issues, we have developed a Schematic Diagram Visualization System (SDViz) designed for maintaining and highlighting contextual information in technical documents, such as schematic and wiring diagrams. Our system incorporates various features to aid in the navigation and diagnosis of faults, as well as maintaining contextual information when tracing components/connections through multiple diagrams. System features include highlighting relationships between components and connectors, diagram annotation tools, the animation of flow through the system, a novel contextual blending method, and a variety of traditional focus+context visualization techniques. We have evaluated the usefulness of our system through a qualitative user study in which subjects utilized our system in diagnosing faults during a standard aircraft maintenance exercise. 相似文献
997.
We consider a firm that faces random demand and receives shipments from a single supplier who faces random supply. The supplier's availability may be affected by events such as storms, strikes, machine breakdowns, and congestion due to orders from its other customers. In our model, we consider a dynamic environment: the probability of disruption, as well as the demand intensity, can be time dependent. We model this problem as a two-dimensional non-homogeneous continuous-time Markov chain (CTMC), which we solve numerically to obtain the total cost under various ordering policies. We propose several such policies, some of which are time dependent while others are not. The key question we address is: How much improvement in cost is gained by using time-varying ordering policies rather than stationary ones? 相似文献
998.
Fallon M. Walton A.J. Stevenson J.T.M. Ross A.W.S. 《Semiconductor Manufacturing, IEEE Transactions on》1994,7(3):272-278
A test structure is described which can be used to optimize the focus of wafer steppers. Simulation is used to examine the effect that some of the design parameters have on the sensitivity of the structure. Finally some practical measurements are presented 相似文献
999.
When learning about a category, people often compare new instances with similar old instances and notice features common to the compared instances. Five experiments demonstrate that such comparisons cause features common to compared instances to be considered more important for the category than equally frequent features that are not common to compared instances. Exp 1 shows that what is learned depends on which instances are compared. Exp 2 investigates the conditions under which comparison-based learning occurs. The next experiments find that these comparisons affect subjective feature frequency (Exp 3) and sensitivity to feature correlations (Exp 4). Exp 5 shows that comparisons during early learning affect what is learned from later instances. The discussion focuses on the implications for models of category representation. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
1000.