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101.
102.
The problem of determining the number of multi-type protection devices and their locations on electrical supply tree networks with subtree dependency is investigated. The aim is to reduce the amount of inconvenience caused to customers that are affected by any given fault on the networks. An appropriate implementation of tabu search is proposed. We exploit a variable neighborhood and a soft aspiration level, and we embed a data structure and reduction tests into the search to speed up the process. Computational tests are performed on randomly generated electrical tree networks varying in size and branch complexity with encouraging results.  相似文献   
103.
104.
This article examines why members of the U.S. House of Representatives voted for H.R. 4437, the controversial 2005 bill to construct a 700‐mile immigration barrier along the U.S.‐Mexican border and to criminalize illegal presence and aid to undocumented immigrants. Logit analysis suggests that being a first‐term House member or a Republican and representing a district that was in the South or the West or heavily blue‐collar substantially boosted the odds of supporting H.R. 4437. If a member's district was disproportionately Asian, Latino, or, especially, African American, he or she was instead more likely to oppose the measure.  相似文献   
105.
1. With the consistent number of part-time nurses in the workforce, hospitals would benefit by more actively integrating them into professional nursing practice. 2. Empowering part-time nurses by affording them the opportunity to provide primary care has the potential to effectively use part-time personnel, decrease the workload for full-time staff, offer more flexibility in scheduling, and result in savings for hospitals in terms of nursing recruitment and retention. 3. This program has successfully developed and implemented a model of primary nursing that places three part-time nurses on a team capable of handling two to three primary patients. The success of this model has been attributed to excellent communication, trust in one another's professional skills, and nursing expertise.  相似文献   
106.
Child welfare workers and agencies are vulnerable to lawsuits. Recent court rulings have more clearly defined the liability of workers. The distinguishing variable is custody. Children injured while in the custody of the state are entitled to sue for damages. Children injured by their parent, even if under the supervision of a child welfare agency, are not entitled to claim a violation of their 14th Amendment rights. These cases are reviewed and strategies designed to minimize vulnerability are offered.  相似文献   
107.
Sex differences in expressiveness are well documented, but the reasons for and correlates of these important differences are not well studied. A comprehensive set of emotion-relevant personality measures was administered to 40 female and 39 male undergraduate participants, who were also videotaped in three situations: engaging in natural social interaction, describing a past emotional experience, and posing various emotions. Videotapes were judged by sets of naive observers as to emotion communicated and overall impression. Expressive females, who appeared friendly and dominant in social interaction, were found to have a hostile/aggressive personality (but this was not true of males). Expressive females also tended to look angry/disgusted when describing happy and sad experiences. The findings suggest that nonverbally skilled, charismatic women (but not men) may often possess a dominant/aggressive but self-controlled personality, in a new twist on the theory that sex differences in expressiveness result in part from the oppression of women in society.This research was supported in part by an intramural research grant from University of California, Riverside.  相似文献   
108.
Past studies have found equivocal support for the ability of young infants to discriminate infant‐directed (ID) speech information in the presence of auditory‐only versus auditory + visual displays (faces + voices). Generally, younger infants appear to have more difficulty discriminating a change in the vocal properties of ID speech when they are accompanied by faces. Forty 4‐month‐old infants were tested using either an infant‐controlled habituation procedure (Experiment 1) or a fixed‐trial habituation procedure (Experiment 2). The prediction was that the infant‐controlled habituation procedure would be a more sensitive measure of infant attention to complex displays. The results indicated that 4‐month‐old infants discriminated voice changes in dynamic face + voice displays depending on the order in which they were viewed during the infant‐controlled habituation procedure. In contrast, no evidence of discrimination was found in the fixed‐trial procedure. The findings suggest that the selection of experimental methodology plays a significant role in the empirical observations of infant perceptual abilities.  相似文献   
109.
In this article, we describe a straightforward method for solving the probability of at least one malignant cell by time t, and the associated hazard function, in the general (i.e., nonhomogeneous) two-stage Moolgavkar-Venzon-Knudson (MVK) model of cancer. The method consists of solving four coupled ordinary differential equations derived from the Kolmogorov backward equations for this process. The relationship of this method to previously proposed solutions is discussed.  相似文献   
110.
In multiple linear regression analysis, each observation affects the fitted regression equation differently and has varying influences on the regression coefficients of the different variables. Chatterjee & Hadi (1988) have proposed some measures such as DSSEij (Impact on Residual Sum of Squares of simultaneously omitting the ith observation and the jth variable), Fj (Partial F-test for the jth variable) and Fj(i) (Partial F-test for the jth variable omitting the ith observation) to show the joint impact and the interrelationship that exists among a variable and an observation. In this paper we have proposed more extended form of those measures DSSEIJ, FJ and FJ(I) to deal with the interrelationships that exist among the multiple observations and a subset of variables by monitoring the effects of the simultaneous omission of multiple variables and multiple observations.  相似文献   
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