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141.
142.
The use of modules in constructing corporate planning systems has been reported by companies such as I.B.M. Xerox, and Standard Oil of New Jersey. The modules may be of organizational units, or of functions such as production, distribution and finance. Modules may also be used for different types of calculations and for generating report output. A module is quite simply a standard unit. Modularity becomes more important as systems grow large, because it is one means of keeping order within large systems. Modularisation is a key concept in structuring large systems, and a useful approach to use in designing procedures for Corporate Planning.  相似文献   
143.
144.
We examined relationships between stream fish assemblages and land use alteration associated with urbanization in 15 lower Piedmont watersheds along an urbanization gradient north of Columbus, western Georgia. Based on land cover data from 2002 Landsat 7 TM imagery aerial photos, streams drained watersheds that were largely urban, developing (suburban), agricultural (pasture), managed pine forest, and unmanaged mixed-forest. We quantified fish seasonally from 3 run-pool segments in each stream, and used a variety of metrics as response variables in analyses of relationships between fish assemblage structure and land use and natural basin variation. In general, Georgia-Index of Biotic Integrity (GA-IBI) values, Bray-Curtis faunal similarity of streams to mean conditions within reference streams, proportions of fish as lithophilic spawners, and fish lacking eroded fins, lesions, tumors decreased with increasing urbanization. Multiple regression indicated that assemblages were explained by a combination of land use and natural basin variables (basin size, average discharge, nearest distance to a larger downstream tributary [colonization source]), with land use variables being important predictors of summer assemblages and natural basin variables being more important in winter and spring assemblages. Non-metric multidimensional scaling (NMDS) ordinations revealed strong separation between assemblages in urban watersheds and forested watersheds, whereas assemblages in agricultural and developing watersheds were intermediate between those in urban and forested watersheds. Our data suggest that fish are reliable indicators of anthropogenic disturbance at the landscape scale, at least seasonally, and may be used to forecast the magnitude of landscape-level changes in stream structure and function associated with the conversion of forests to urban/suburban land in the Southeast.  相似文献   
145.
It was hypothesized that the cognitive representation of distances between locations in an environment is a function not only of the environment's structure, but also of a person's pattern of travel within the environment. In the present study subjects were exposed to an experimental environment in which some locations were separated either by an opaque or a transparent barrier and other locations were not separated by any barrier. As subjects learned where the locations were, they were required to follow a specific route that allowed travel between some locations in each category but not others. Afterward subjects were asked to reproduce from memory the separation between pairs of locations. The results supported the hypothesis. Recalled distance between locations was significantly affected by both movement patterns of subjects and structural aspects of the environment (type of barrier and actual separation between locations). These results are interpreted in terms of the types of information made available through particular movement patterns and the corresponding salience of that information.  相似文献   
146.
While births may be dichotomous, fertility intentions are not inherently so. Intentions are predictions about the future and, as such, are couched in considerable uncertainty. Ignoring this uncertainty hides much of what could be learned from data on fertility intentions. This paper presents a model which allows analysis of the full range of intentions. After selecting a sample of women in the later stage of childbearing (e.g., those who intend fewer than two additional children) from the 1965and 1970 National Fertility Studies, it is shown that: (1) substantial portions of women at this stage of the reproductive life cycle were indeed uncertain of their parity-specific intention; (2) this certainty, like more firm intentions, varies by age and parity as the model predicts; and (3) there were significant shifts in the level of certainty between 1965 and 1970. Specifically, while intentions for third, fourth, and fifth births declined, more women “didn’t know” if they intended to have another child or not. Among those not intending another child, more seemed uncertain of this intention in 1970 than did comparable women in 1965. In contrast, those intending another child seemed more certain. These changes in intention and uncertainty indicate that the observed decline in intended parity was tentative. Post-1970 evidence suggests that this tentative decline has become an unequivocal one.  相似文献   
147.
Traditional (non-stochastic) iterative methods for optimizing functions with multiple optima require a good procedure for selecting starting points. This paper illustrates how the selection of starting points can be made automatically by using a method based upon simulated annealing. We present a hybrid algorithm, possessing the accuracy of traditional routines, whilst incorporating the reliability of annealing methods, and illustrate its performance for a particularly complex practical problem.Now at the Statistical Laboratory, University of Cambridge, 16 Mill Lane, Cambridge, CB2 1SB, UK.  相似文献   
148.
The objectives of this research are first to empirically replicate Advanced Manufacturing Technology (AMT) utilization taxonomies identified in foregoing research, second to investigate the relationship between patterns of AMT utilization and manufacturing capabilities attainment, and third to explore differences in context, and performance across AMT groups. Theories of performance frontiers and capability progression provide the basis for our hypotheses. Data were collected from 224 U.S. manufacturing plants in industries considered to have potential utilizations of AMTs. A cluster analysis of the data yields a solution that closely resembles a previous AMT utilization taxonomy, including four groups labeled, respectively, as Traditionalists, Generalists, High Investors, and Designers. Significant manufacturing capability differences across these four groups indicate that plants that utilize a broader scope of AMTs enjoy a greater breadth of manufacturing capabilities. The implied capability attainment pattern is consistent with cumulative capability theory. However, the results suggest that cost capability is not included in the capability mix when broad‐based AMT utilization is the enabler of capability gains. A post hoc exploration of the AMT groups indicates significant differences in performance across the groups. Collectively, the results extend prior research by providing added insights into the possible rationale and impact of AMT utilization patterns.  相似文献   
149.
Helping individuals make a career decision is a key aim of career counseling. Determining how to encourage self-regulated learning and behaviors needed to achieve this goal often underlies career interventions. The English version of the Career Exploration Behavior survey (CEB-E) measures activities individuals engage in to learn about career options. The present study explored the psychometric properties of the CEB and its impact on various career outcomes. In the first study (N = 498), a good-fitting second-order factor model with four group-level scales and loadings was retained as the best model. In the second study (N = 143), convergent validity and incremental validity of the CEB dimensions were explored through correlation and regression analyses. The CEB predicted commitment making, metacognitions, and vocational identity. Results suggest the CEB-E is a psychometrically sound assessment of career exploration behaviors with potential utility for theory development, program evaluation, and monitoring client progress.  相似文献   
150.
An exploratory qualitative study was conducted to explore how child welfare administrators use research evidence in decision-making. Content analysis revealed that a cultural shift toward evidence-based practice (EBP) is occurring in Canadian child welfare organizations and multiple types of evidence inform policy decisions. Barriers to using evidence include individual, organizational, and environmental factors. Facilitating factors include the development of internal champions and organizational cultures that value EBP. Integrating research into practice and policy decisions requires a multifaceted approach of creating organizational cultures that support research utilization and supporting senior bureaucrats to use research evidence in policy development.  相似文献   
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