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471.
This study investigates the impact of worker learning, worker flexibility, and labor attrition on the system performance of a dual resource constrained (DRC) job-shop. The effects of learning and labor attrition have not been previously addressed in DRC literature. Results from the study, consistent with previous literature, show that the greatest benefits are achieved when inter-departmental worker flexibility is incrementally introduced into the system. In addition, the learning environment, which depends on the initial processing time of jobs and the learning rates of workers, is shown to impact the acquisition of flexibility. The study also shows that the impact of labor attrition on system performance under certain shop conditions may be significant.  相似文献   
472.
Few studies of just-in-time (JIT) implementation examine their significance in make-to-order manufacturing environments. This study examines the relative importance of several operating variables that are characteristic features of JIT systems within such environments in North America. The results suggest that the most salient features of JIT for make-to-order and assemble-to-order firms are the elimination of waste (in the form of time and defects), reduced setup time, reduced lotsize, and a smaller pool of suppliers. In addition, the results suggest that the use of non-domestic suppliers can possibly hinder efforts at JIT implementation of materials procurement.  相似文献   
473.
The purpose of this study is to examine the reliability of the skin tone measures in the widely used American National Election Studies data collection (AN  相似文献   
474.
Population Research and Policy Review - This paper examines the impact of school starting age on teenage marriage and motherhood in Vietnam. The investigation uses data from the 2009 Vietnam...  相似文献   
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477.
Interdependence is a defining feature of close relationships, and alcohol use is one domain where one person’s motivations and behaviors can affect a partner’s well-being. Concern about partner drinking is a gauge that determines whether a partner’s alcohol use has the potential to be problematic to the relationship, and brief and efficient measurement of this construct can be used to serve clinicians, scientists, and practitioners. Across four studies (N = 1,807), we use item response theory analysis to present a 3-item brief screening tool assessing concern about partner drinking: Thinking about your Partner’s Drinking-3 (TPD-3). The TPD-3 revealed strong test–retest reliability and expected patterns of convergent, concurrent, and incremental validity with perceived partner drinking and alcohol-related consequences, behavioral responses to partner drinking, and relationship well-being. We present the TPD-3 as a useful screening tool and for measurement of concern about partner drinking when efficient assessment is desired.  相似文献   
478.
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   
479.
Technology is pervasive in homes of families with young children, despite evidence for negative associations between infant exposure to screen‐based media and cognitive development that has led the American Academy of Pediatrics (AAP) to discourage parents from exposing children under the age of 18 months to any kind of screen time (AAP, 2016). Here, we apply a propensity score matching approach to estimate relations between electronic screen‐based media use in infancy and executive function in early toddlerhood. In an international sample of 416 firstborn infants, parental report of regular exposure to screen‐based media at 4 months predicted poorer performance on a test of inhibition at 14 months, but was unrelated to either cognitive flexibility or working memory at 14 months. Results of this study are therefore consistent with the view that early exposure to screen‐based media adversely affects the development of executive function.  相似文献   
480.
To meet the [African] crisis one must turn to agricultural-led growth. But, based on historical experience, an agricultural-led strategy must be framed in no less than a twenty-year horizon and must entail a combination of technological innovation, policy reform, and institutional restructuring because each, by itself, is limited. (Eicher, 1989)  相似文献   
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