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231.
This research investigates the impact of lot splitting in unbalanced production systems, under a variety of experimental conditions. Scheduling policies specifically designed for use in the presence of a long-term bottleneck, a condition frequently encountered in practice, are developed and tested. Results indicate that when steps are taken at nonbottleneck work centers to capitalize on capacity imbalances through increasing the number of setups and, hence, the variety of products produced, shop effectiveness is improved. The results also indicate that scheduling policies that tend to increase the size of the average process batch retard the overlapping of operations, which is critical to the success of the lot-splitting methodology in reducing flow time. Finally, it is shown that increasing capacity at nonbottleneck work centers along with implementation of effectiveness-oriented scheduling polices leads to improved shop performance.  相似文献   
232.
Many prosocial behaviors involve social risks such as speaking out against a popular opinion, bias, group norm, or authority. However, little is known about whether adolescents’ prosocial tendencies develop over time with their perceptions of social risks. This accelerated longitudinal study used within-subject growth-curve analyses to test the link between adolescents' prosocial tendencies and social risk perceptions. Adolescents completed self-reports annually for 3 years (N = 893; Mage = 12.30 years, 10–14 years at Wave 1, and 10–17 years across the full study period; 50% girls, 33% White non-Latinx, 27% Latinx, 20% African American, 20% mixed/other race). The association between social risk tolerance and prosocial tendencies changed significantly across adolescence. Specifically, for younger adolescents, more prosocial tendencies were associated significantly with less social risk tolerance, whereas for relatively older adolescents, more prosocial tendencies were associated marginally with more social risk tolerance. Additional individual differences by empathy (but not sensation seeking) emerged. These findings suggest that prosocial tendencies across adolescence may be associated with an underlying ability to tolerate social risks.  相似文献   
233.
Although a decline in adolescents' well-being has repeatedly been reported, longitudinal evidence for this development is rare and time-varying factors like teacher autonomy support that could be associated with this trend have sparsely been investigated. Therefore, the present study examined how the temporal development of perceived autonomy support from their German language arts teachers is related to changes in four different facets of students' well-being. Longitudinal data from 3446 adolescents from Germany (NSchools = 178) on five measurement points (Grades 5–9) were analyzed using latent growth curve models. Satisfaction with school, enjoyment of school, and self-rated health decreased over time, while social integration remained stable. Perceived teacher autonomy support also declined between Grades 5 and 9. Furthermore, baseline levels of perceived teacher autonomy support and facets of well-being were positively related. Finally and most importantly, our results indicated that changes in perceived teacher autonomy support were positively associated with the development of satisfaction with school, enjoyment of school, and self-rated health, but not social integration. The findings suggest that perceived teacher autonomy support plays an important role in the development of students' well-being in adolescence.  相似文献   
234.
Job shops have long faced pressures for improvement in a challenging and volatile environment. Today's trends of global competition and shortening of product life cycles suggest that both the challenges and the intensity of market volatility will only increase. Consequently, the study of tactics for maximizing the flexibility and responsiveness of a job shop is important. Indeed, there is a significant body of literature that has produced guidelines on when and how to deploy tactics such as alternate routings for jobs and transfers of cross‐trained workers between machines. In this paper we consider a different tactic by adjusting the length of workdays. Hours in excess of a 40‐hour week are exchanged for compensatory time off at time and a half, and the total amount of accrued compensatory time is limited to no more than 160 hours in accordance with pending legislation. We propose several simple flexible workday policies that are based on an input/output control approach and investigate their performance in a simulated job shop. We find significant gains in performance over a fixed schedule of eight hours per day. Our results also provide insights into the selection of policy parameters.  相似文献   
235.
Culture provides a context in which emotion socialization is embedded, and the bidirectional effects between parents’ emotion socialization and children's emotional behaviors may work differently across cultures. To understand how emotion socialization may be shaped by the cultural context, we examined the moderating role of Asian cultural values in bidirectional associations between maternal emotion socialization practices and child anger and sadness. Seventy-four U.S. Chinese immigrant mothers (Mage = 40.71 years, SD = 3.61) completed measures assessing their Asian cultural values and parenting style. Children experienced a disappointment task in the lab (Cole, 1986), and mothers and their children (Mage = 6.73 years, SD = .95; 55% female) were observed at two different time intervals. Mothers’ socialization practices (emotion dismissing, emotion coaching, and moral and behavioral socialization) and children's anger and sadness responses at both intervals were coded. Mothers’ greater Asian cultural values buffered the negative effects of their emotion dismissing practices on children's anger and sadness. However, Asian cultural values did not impact the effects of children's anger and sadness on mothers’ emotion dismissing practices. When mothers endorsed fewer Asian values, their emotion coaching practices reduced children's anger and sadness. Children's anger and sadness evoked more emotion coaching practices when mothers endorsed lower levels of Asian cultural values. In addition, children's anger and sadness evoked greater moral and behavioral responses from their mothers when mothers endorsed more Asian values. Overall, findings underscored the importance of cultural values in the interplay between mothers’ emotion socialization practices and children's emotions.  相似文献   
236.
A recent study conducted by Abad [1] described a method of determining the optimal price and lot size when the supplier offers all-unit quantity discounts. The author developed a procedure using centralized and decentralized approaches. According to the author's suggestion, further study is necessary to determine if the decentralized approach always provides an optimal solution. In the present study, an attempt is made to investigate the uniformity between the centralized and decentralized approaches and to verify whether the decentralized approach always yields optimal solutions.  相似文献   
237.
Previous research has yielded a procedure for a retailer to determine the optimal lot size and selling price when a supplier offers all-unit quantity discounts and demand is a decreasing function of price. In this paper, we extend that research by allowing for shortages. An algorithm is presented that determines the optimal lot size, order level, and selling price for a class of demand functions, including the constant price-elasticity and linear demand functions.  相似文献   
238.
Early screening for language problems is a priority given the importance of language for success in school and interpersonal relationships. The paucity of reliable behavioral instruments for this age group prompted the development of a new touchscreen language screener for 2-year-olds that relies on language comprehension. Developmental literature guided selection of age-appropriate markers of language disorder risk that are culturally and dialectally neutral and could be reliably assessed. Items extend beyond products of linguistic knowledge (vocabulary and syntax) and tap the process by which children learn language, also known as fast mapping. After piloting an extensive set of items (139), two phases of testing with over 500 children aged 2; 0–2; 11 were conducted to choose the final 40-item set. Rasch analysis was used to select the best fitting and least redundant items. Norms were created based on 270 children. Sufficient test-retest reliability, Cronbach's alpha, and convergent validity with the MB-CDI and PPVT are reported. This quick behavioral measure of language capabilities could support research studies and facilitate the early detection of language problems.  相似文献   
239.
This study compares the performance of three artificial neural network (ANN) approaches—backpropagalion, categorical learning, and probabilistic neural network—as classification tools to assist and support auditor's judgment about a client's continued financial viability into the future (going concern status). ANN performance is compared on the basis of overall error rates and estimated relative costs of misclassificaticn (incorrectly classifying an insolvent firm as solvent versus classifying a solvent firm as insolvent). When only the overall error rate is considered, the probabilistic neural network is the most reliable in classification, followed by backpropagation and categorical learning network. When the estimated relative costs of misclassification are considered, the categorical learning network is the least costly, followed by backpropagation and probabilistic neural network.  相似文献   
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