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671.
OSCAR F. GARZA ALEX J. GOLUB JACK F. LUPER ALAN W. NEEBE 《Production and Operations Management》1992,1(2):151-158
R. J. Reynolds Tobacco USA (RJR) is currently implementing a microcomputer-based decision support system to computerize and optimize the selection of patterns for loading cases of finished product into truck trailers at RJR's Central Distribution Center. This system allows for the efficient loading of trucks with less supervision. Total annual savings from reduced personnel and shipping costs is approximately $850,000. In addition to these benefits, the system is a stepping stone for trailer loading automation and the integration of a comprehensive load planning system. 相似文献
672.
Artificial neural networks are new methods for classification. We investigate two important issues in building neural network models; network architecture and size of training samples. Experiments were designed and carried out on two-group classification problems to find answers to these model building questions. The first experiment deals with selection of architecture and sample size for different classification problems. Results show that choice of architecture and choice of sample size depend on the objective: to maximize the classification rate of training samples, or to maximize the generalizability of neural networks. The second experiment compares neural network models with classical models such as linear discriminant analysis and quadratic discriminant analysis, and nonparametric methods such as k-nearest-neighbor and linear programming. Results show that neural networks are comparable to, if not better than, these other methods in terms of classification rates in the training samples but not in the test samples. 相似文献
673.
Social Indicators Research - Monitoring progress towards the Sustainable Development Goals by 2030 requires the global community to disaggregate targets along socio-economic lines, but little has... 相似文献
674.
Population Research and Policy Review - Often, demographers charged with projecting enrollments for school districts are asked to provide a range of future enrollments, as point estimates are not... 相似文献
675.
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677.
Justin F. Jackson 《Journal of historical sociology》2020,33(1):116-133
Between 1898 and 1934, in synchronous and successive U.S. military interventions and occupations in Cuba, Puerto Rico, the Philippines, Haiti, and the Dominican Republic, American soldiers made public works, and especially roads, into a global technology of imperial power. This essay examines infrastructure as a factor in state formation and capitalist transition in these five different imperial spaces as a way to study U.S. empire, and its effects on foreign societies, through a comparative, global, and intra‐imperial approach often precluded by the methodological nationalism of historical and sociological literatures. Despite significant differences between these sites of U.S. war and occupation, both prior to American interventions and during them, U.S. military public works expressed and advanced a common political‐economic logic of state centralization and capital accumulation. Colonial and post‐colonial political institutions and political economies, the strength of central governments, the extent of plantation agriculture and rural proletarianization, world commodity markets, and geography and natural events varied, but determined U.S. imperial infrastructure's outcomes. By the 1930s, the U.S. military had elevated infrastructural improvement to a key repertoire of American imperial power in the world, and one which persisted as the United States turned away from formal colonialism in the era of the Cold War and decolonization. 相似文献
678.
Urban Ecosystems - Generalist wildlife species often thrive in urban environments because of increased anthropogenic resources. However, human-wildlife interactions, especially if negative, raise... 相似文献
679.
Tessa M. L. Kaufman Hae Yeon Lee Aprile D. Benner David S. Yeager 《Journal of research on adolescence》2020,30(3):769-786
The present research examined how school contexts shape the extent to which beliefs about the potential for change (implicit theories) interact with social adversity to predict depressive symptoms. A preregistered multilevel regression analysis using data from 6,237 ninth‐grade adolescents in 25 U.S. high schools showed a three‐way interaction: Implicit theories moderated the associations between victimization and depressive symptoms only in schools with high levels of school‐level victimization, but not in schools with low victimization levels. In high‐victimization schools, adolescents who believed that people cannot change (an entity theory of personality) were more depressed when they were victimized more frequently. Thus, the mental health correlates of adolescents’ implicit theories depend on both personal experiences and the norms in the context. 相似文献
680.
Urban Ecosystems - Critical resources for birds nesting in cities can support populations in spite of the challenges imposed by urbanization, and the identification of such resources can shed light... 相似文献