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排序方式: 共有457条查询结果,搜索用时 15 毫秒
51.
This paper describes early planning stages of a nurse-managed clinic to offer primary health care services in a nontraditional university setting. A community needs assessment was conducted with quantitative and qualitative findings reported. This unique setting triggered a number of considerations in planning for services. Recommendations for health services and resources for the university community are discussed. 相似文献
52.
Gunther Maier 《Papers in Regional Science》1991,70(2):133-147
The paper extends the well-known economic search model to take into account the fact that all search takes place in two-dimensional space. This adds arouting problem to thestopping problem usually discussed in the search literature. The paper shows that these two problems are interdependent and can only be solved simultaneously. This relates thespatial search problem as it is discussed in this paper toNP-Complete problems like the traveling salesman problem, some of the most complex problems in mathematics. The paper discusses this relationship and closes with some suggestions about how to circumvent this complexity.An earlier version of this paper was presented at the 30th European Congress, Istanbul, August 1990. 相似文献
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Momotenko D Cortes-Salazar F Lesch A Wittstock G Girault HH 《Analytical chemistry》2011,83(13):5275-5282
This paper presents a microfluidic push-pull probe for scanning electrochemical microscopy (SECM) consisting of a working microelectrode, an integrated counter/reference electrode and two microchannels for pushing and pulling an electrolyte solution to and away from a substrate. With such a configuration, a droplet of a permanently renewed redox mediator solution is maintained just at the probe tip to carry out SECM measurements on initially dry substrates or in microenvironments. For SECM imaging purposes, the probe fabricated in a soft polymer material is used in a contact regime. SECM images of various gold-on-glass samples demonstrate the proof-of-concept of a push-pull probe for local surface activity characterization with high spatial resolution even on vertically oriented substrates. Finite element computations were performed to guide the improvement of the probe sensitivity. 相似文献
55.
We propose a new algorithm for vector quantization, the Activity Equalization Vector quantization (AEV). It is based on the winner takes all rule with an additional supervision of the average node activities over a training interval and a subsequent re-positioning of those nodes with low average activities. The re-positioning is aimed to both an exploration of the data space and a better approximation of already discovered data clusters by an equalization of the node activities. We introduce a learning scheme for AEV which requires as previous knowledge about the data only their bounding box. Using an example of Martinetz et al. [1], AEV is compared with the Neural Gas, Frequency Sensitive Competitive Learning (FSCL) and other standard algorithms. It turns out to converge much faster and requires less computational effort. 相似文献
56.
Projection or Persuasive Press? Contrary Effects of Personal Opinion and Perceived News Coverage on Estimates of Public Opinion 总被引:1,自引:1,他引:0
This study explores the effects of personal opinion and perceived media content on individuals' assessments of public opinion, as well as the curious phenomenon that, although people perceive public agreement with their own point of view, they tend to see press coverage as disagreeable. One hypothesis, based on theories of projection of personal opinion, predicts that people will see public opinion as much like their own, but a contrary outcome is suggested by 2 interrelated hypotheses, the hostile media effect and the persuasive press inference. Data were collected on 4 issues from a large, representative national sample and provided evidence for all 3 effects. Projection received the most consistent support, but findings indicate that this assimilation effect can be substantially offset by media coverage seen as both disagreeable and influential. 相似文献
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Differences in processing representations of conditioned and unconditioned stimuli (CSs and UCSs) may result from either their temporal order in training (i.e., CSs precede UCSs) or the greater biological significance of UCSs. The CS- and UCS-preexposure effects were used to probe this question. These effects are similar except that context extinction between preexposure and training more readily attenuates the UCS- than the CS-preexposure effect. In Experiments 1, 2, and 5, context extinction following preexposure to the stimulus that later served as Event 1 in Event 1?→?Event 2 pairings alleviated the response deficit due to Event 1 preexposure if Event 1 was biologically significant. In Experiments 3 and 4, context extinction alleviated the response deficit due to Event 2 preexposure if Event 2 was biologically significant. Thus, biological significance and not temporal order determines how a representation will be processed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
60.
In 4 conditioned lick suppression experiments with rats, the combined effects of latent inhibition treatment followed by overshadowing treatment were assessed as a test of the comparator hypothesis's (R.R. Miller & L.D. Matzel, 1988) explanations of overshadowing and latent inhibition. Experiments 1 and 2 confirmed the prediction of the comparator hypothesis that combined latent inhibition and overshadowing treatments attenuate the response deficit produced by either treatment alone. Furthermore, consistent with the comparator hypothesis, posttraining changes in the associative status of the putative comparator stimulus altered responding to the target conditioned stimulus (Experiment 3), and switching contexts between latent inhibition and overshadowing treatments (Experiment 4) eliminated the interaction between the latent inhibition and overshadowing treatments. 相似文献