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741.
Neural correlates of anticipatory and reactive saccades were studied in 4‐month‐old infants by recording high‐density event‐related potentials. Infants were presented with a fixed sequence of stimulus presentation to which they rapidly showed anticipatory saccades, as well as continuing with some reactive (stimulus‐driven) saccades. As in a previous study, no clear evidence was found for adultlike, saccade‐related potentials, although some presaccadic differences between reactive and anticipatory saccades were observed. Infants also showed different stimulus offset‐related effects preceding the 2 types of trials with a right‐frontal positivity when an anticipatory look follows, but only left‐frontal positivity when a reactive saccade follows.  相似文献   
742.
This article describes the development of a generic loss assessment methodology, which is applicable to earthquake and windstorm perils worldwide. The latest information regarding hazard estimation is first integrated with the parameters that best describe the intensity of the action of both windstorms and earthquakes on building structures, for events with defined average return periods or recurrence intervals. The subsequent evaluation of building vulnerability (damageability) under the action of both earthquake and windstorm loadings utilizes information on damage and loss from past events, along with an assessment of the key building properties (including age and quality of design and construction), to assess information about the ability of buildings to withstand such loadings and hence to assign a building type to the particular risk or portfolio of risks. This predicted damage information is then translated into risk-specific mathematical vulnerability functions, which enable numerical evaluation of the probability of building damage arising at various defined levels. By assigning cost factors to the defined damage levels, the associated computation of total loss at a given level of hazard may be achieved. This developed methodology is universal in the sense that it may be applied successfully to buildings situated in a variety of earthquake and windstorm environments, ranging from very low to extreme levels of hazard. As a loss prediction tool, it enables accurate estimation of losses from potential scenario events linked to defined return periods and, hence, can greatly assist risk assessment and planning.  相似文献   
743.
This paper presents the current Dutchsociotechnical design approach to integralorganizational renewal in a contextual way. Both itsdesign theory and intervention processes are reviewedand some aggregated empirical evidence is presented. Next, thepaper compares the ideas developed in the Dutch approachto those presented in its American, Scandinavian, andAustralian counterparts. It is concluded that, at a meta-level, they all share the ideal ofparticipative democracy, while at the conceptual level,these distinctive approaches appear quite incompatible.Notwithstanding substantial diversity, it is presumed these approaches can be seen as localmanifestations of a single sociotechnicalparadigm.  相似文献   
744.
Abstract

This study investigated the gender-specific, self-reported sexual behaviors and attitudes of never-married college students attending a southeastern university in 1973 and 1988. Data were collected by means of a mailed questionnaire that remained essentially unchanged for both years. The authors found that both men and women reported an increase in heterosexual relationships that included sexual intercourse and a decrease in nonsexual relationships with the other gender. The majority of the students perceived themselves as adequately informed about sexuality and satisfied with their relationships, although the proportion of men who reported being satisfied with their relationships declined over the 15 years. The students indicated that sexuality education should focus primarily on information about AIDS and on preparation for marriage.  相似文献   
745.
Earlier work with decision trees identified nonseparability as an obstacle to minimizing the conditional expected value, a measure of the risk of extreme events, by the well-known method of averaging out and folding back. This first of two companion papers addresses the conditional expected value that is defined as the expected outcome assuming the exceedance of a threshold β, where β is preselected by the decision maker. An approach is proposed to overcome the need to evaluate all policies in order to identify the optimal policy. The approach is based on the insight that the conditional expected value is separable into two constituent elements of risk and can thus be optimized along with other objectives, including the unconditional expected value of the outcome, by using a multiobjective decision tree. An example of sequential decision making for improving highway capacity is given.  相似文献   
746.
Today's manufacturing enterprises face tremendous competitive pressures. Global competition, together with market demands for customized products delivered just in time, place tremendous pressures on manufacturers. The emerging global economy is rapidly replacing local markets. The emergence of open markets, reductions in trade barriers, and improvements in transportation and communications links have led to a situation where local competition and markets operate in the context of global standards. This open infrastructure allows manufacturers to respond to these challenges by working more closely with their suppliers and customers, and by building extended enterprises across the whole value chain. Such extended enterprises present great challenges in terms of redesigning business processes to create a competitive advantage from the linkages they include. This paper describes the manufacturing philosophies currently in vogue. Any manufacturing or related business will need to use them, albeit tailored to its own circumstances, in one form or the other, to ensure its prosperity.  相似文献   
747.
The two-parent disease-genotype association problem is studied from the point of view of a coefficient of association between the disease phenotype of the child and the disease phenotypes of the parents, in the presence of some genotypic information about the parents. This coefficient of partial association is derived, and certain tests of hypotheses are constructed. The results are shown to be useful in estimation of recurrence risks, and in understanding the nature of the association between child and parental disease phenotypes.  相似文献   
748.
It is recognized in the field of social work that institutionalization of any people produces certain negative and detrimental patterns of behaviour. In geriatrics present practice is away from institutionalization. The aged are encouraged to find employment or interests and to move out of institutions. Emphasis is placed upon individual flats and self-care with any supportive services that are necessary. More and more the emphasis in child care is upon foster care in ordinary homes scattered through the general community and culture to which the children belong.  相似文献   
749.
750.
The author presents a robust F-test for comparing nested linear models. It is suggested that the approach will be attractive to practitioners because it is based on the familiar F-statistic and corresponds to the common practice of reporting F-statistics after removing obvious outliers. It is calibrated in terms of a real parameter that can be directly interpreted as the willingness of the data analyst to remove observations, and the sensitivity of the F-statistic to this parameter is easily examined. The procedure is evaluated with a simulation study where a scale mixture distribution is used to generate outliers. The procedure is also applied to some data where the occurrence of an outlier is confounded with the significance of a regression term. This provides a comparison of two competing models for the data: one removing an outlier and the other including an additional regression term instead.  相似文献   
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