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971.
We solve the problem of petroleum products distribution through oil pipelines networks. This problem is modelled and solved using two techniques: A heuristic method like a multiobjective evolutionary algorithm and Mathematical Programming. In the multiobjective evolutionary algorithm, several objective functions are defined to express the goals of the solutions as well as the preferences among them. Some constraints are included as hard objective functions and some are evaluated through a …  相似文献   
972.
Abstract

This study attempted to identify the predictors of entrepreneurial behavior by assessing a series of variables that included teamwork skills and demographic variables, and to explore teachers’ experiences with teamwork. A sample of 367?K-12 public school teachers completed the survey. The findings indicated that teamwork predicts entrepreneurial behavior. Most participants received teamwork training through their school districts. Barriers to teamwork included time constraints, individual differences, and inability to collaborate.  相似文献   
973.
CHILDREN with mental retardation and children with normal intelligence were asked to perform a series of tasks or to only imagine performing them. They were then asked to remember which tasks had been performed and which had been imagined at an immediate interview and after an eight week delay. There were no overall differences between the two groups in the number of correct responses. However, all children gave more correct responses to specific probes than to open‐ended probes and remembered activities performed better than those imagined. Performance was more accurate for both groups at the immediate interview than at the delayed interview. Responses to questions about activities neither performed nor imagined were good for both groups of children to the initial questions but decreased significantly in response to a follow‐up probe. Accuracy of responses to these misleading questions decreased over the eight week delay.  相似文献   
974.
In answer to a reader's question, the author of this column addresses the legal and ethical responsibilities of a Lamaze Certified Childbirth Educator who agrees to attend her students' drug-free delivery.  相似文献   
975.
Children's number sense in kindergarten was used to predict their calculation fluency in second grade (N = 198). Using block entry regression, usual predictors of age, reading, memory, and verbal and spatial cognition were entered in the first block and number sense measures were added in the second block. Number sense measures contributed a significant amount of variance over and above the more general predictors (26%-42%). Uniquely predictive subareas were active memory for numbers, number knowledge, and number combinations, with number combinations standing out as the strongest single predictor. Number sense screening in kindergarten, using "at-risk" versus "not-at-risk" criteria, successfully ruled out 84% of the children who did not go on to have calculation fluency difficulties and positively identified 52% of the children who later showed fluency difficulties. The relation of early number skills to later calculation fluency has important implications for math screening and intervention.  相似文献   
976.
PROBLEM: After the Soviet Union dissolved in 1989, it became apparent that there was little recognition of the problems of child abuse and neglect, professionally, legally, or societally. There were no effective systems or laws in place to deal with these problems. METHOD: Beginning in 1995 the Children's Mental Health Alliance, in conjunction with the Open Society Institute began conducting trainings in Eastern Europe [Journal of the American Academy of Child Adolescent Psychiatry 39 (2000) 660]. Originally 18 countries from the Baltics to the Balkans participated. A program was elaborated which would proceed in several stages: (1) training mental health professionals to deal with child abuse and neglect (CAN); (2) teaching multidisciplinary team work and fostering the development of multidisciplinary NGOs focused on CAN; (3) promoting the self-sufficiency of these NGO's which would then facilitate social and legal reform and increase public awareness of the problem. Specific methods included multi-national trainings, assignment of mentors to the developing teams who maintained weekly contact with the teams and made yearly site visits to their countries, and overseeing project grants from OSI. RESULTS: NGO's had been established and registered in 11 countries, many establishing a network of programs within their countries. By 2000, over 3800 mental health professional had been trained, either directly by the program or by the trainees of the program. By the end of 2000, over 17,000 other professionals (lawyers, police, judges, educators, other physicians, etc.) had been trained by the network. CONCLUSION: While more work needs to be in this region, the teams in 11 countries have made solid starts.  相似文献   
977.
Numerical exercises are presented on the thermally induced motion of internally heated beams under various heat transfer and structural boundary conditions. The dynamic displacement and dynamic thermal moment of the beam are analyzed taking into consideration that the temperature gradient is independent as well as dependent on the beam displacement. The effect of length to thickness ratio of the beam on the thermally induced vibration is also investigated. The type of boundary conditions has its influence on the magnitude of dynamic displacement and dynamic thermal moment. A sustained thermally induced motion is observed with progress of time when the temperature gradient being evaluated is dependent on the forced convection generated due to beam motion. A finite element method (FEM) is used to solve the structural equation of motion as well as the heat transfer equation.  相似文献   
978.
Postsecondary institutions in the United States, including member institutions of the National Collegiate Athletic Association (NCAA), are charged with the responsibility of cultivating positive learning environments where all students have an opportunity to excel regardless of their demographic backgrounds (e.g., race, socioeconomic status, etc.). However, one subgroup of students these institutions have persistently been unable to retain and graduate at rates comparable to their peers is Black male student athletes. Previous research has cited unwelcoming campus climates, inadequate academic support, and an overemphasis on athletics as key factors that contribute to Black male student athletes' academic underperformance and negative psychosocial experiences at these institutions. The purpose of this article is to present a series of strategies and recommendations for enhancing Black male student athletes' educational experiences and holistic development at postsecondary institutions in the U.S. A review of scholarly literature on Black male student athletes, college student development theories, and student athlete support programs was conducted to identify best practices related to the phenomena. An analysis of the literature led to the creation of the Excellence Beyond Athletics (EBA) approach. The EBA approach consists of the following six holistic development principles (HDPs): (1) self-identity awareness, (2) positive social engagement, (3) active mentorship, (4) academic achievement, (5) career aspirations, and (6) balanced time management.  相似文献   
979.
980.
MplusAutomation is a package for R that facilitates complex latent variable analyses in Mplus involving comparisons among many models and parameters. More specifically, MplusAutomation provides tools to accomplish 3 objectives: to create and manage Mplus syntax for groups of related models; to automate the estimation of many models; and to extract, aggregate, and compare fit statistics, parameter estimates, and ancillary model outputs. We provide an introduction to the package using applied examples including a large-scale simulation study. By reducing the effort required for large-scale studies, a broad goal of MplusAutomation is to support methodological developments in structural equation modeling using Mplus.  相似文献   
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