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821.
The oil supply chain is facing new challenges due to emerging issues such as new alternative energy sources, oil sources scarcity, and price variability with high impact on demand and production and profit margins reduction. Additionally, the existence of large, complex and world wide spread businesses implies a complex system to be managed where distribution can be seen as one of the key areas that needs to be efficiently and effectively managed. Different types of distribution modes characterize the oil supply chain where the pipeline mode is one of the most complex to operate when having multiproduct characteristics. This paper addresses the planning of a generic oil derivatives transportation system characterized by a multiproduct pipeline that connects a single refinery to a storage tank farm. Two alternative mixed integer linear programming models (MILP) that aim to attain a set of planning objectives such as fulfilling costumers’ demands (which is mandatory) while minimizing the medium flow rate are developed. Additionally, final inventory levels are avoided to be excessively low. A real world scenario of a Portuguese company is used to validate and compare the two alternative MILP models developed in this paper.  相似文献   
822.
Few empirical studies have examined the effect of personal values on the importance attached by individuals to training and development in organizations. We argue that personal values play an important role in decision-making processes (i.e. commitment to training and development) and that such values are the product of socialization processes operating at an organizational and societal level. Questionnaire data were collected from 340 Irish and Canadian line managers to test the hypothesis that personal values affect the importance attached by respondents to training and development. Capability values were found to be a significant positive predictor of the perceived importance of training and development. The findings emphasize the need for simultaneously examining both personal values and organizational factors as predictors of training and development activity.  相似文献   
823.
The main purpose of this research was to examine the relationship between adult students' self-directed learning (SDL) ability and instructional technology (IT) competency in an online course. The study also investigated motivation and learning strategies that the students used to learn IT. The research involved surveying 198 continuing education professionals who took online courses at a large Midwest state university. The results indicate a statistically significant positive correlation between SDL ability and IT competency in students with above average SDL ability. The results also indicate that motivation is an important factor for learning technology in an online course regardless of the students' SDL ability. Additionally, the results show that students with higher level of SDL ability are likely to exhibit higher level of self-efficacy for learning and performance, and higher level of effort regulation.  相似文献   
824.
This study explored whether career orientation is stable and whether predominant types exist by looking at the differences in specific demographic variables (age, years of work experience, employment level, gender, type of job and education level). These were examined through the framework of career success orientation in a Korean wireless communications company. The findings show that career success orientations were not the same by age, length of work experience, and employment level, and dominant career success orientations were based only on education level. The results imply that there are either generation differences or changes in career orientation and that theoretical re-investigation is needed in researching dominant career orientation by gender.  相似文献   
825.
This paper explores the moderating role of cultural values on relationships between participation satisfaction (PS) and employees’ organizational commitment (OC). A survey of 1390 employees of Bharat Sanchar Nigam Limited, a Government of India Public Sector Undertaking providing telecommunication services across India, shows that PS is directly related to OC, and is moderated by employees’ cultural values at individual level. The form of moderation reveals: positive and insignificant relationship between PS and affective commitment for employees high in uncertainty avoidance; positive and significant relationship between PS and normative commitment for employees high in individualism/collectivism, low in masculinity/femininity, and low in power distance. No moderation has been found in the relationship between PS and continuance commitment.  相似文献   
826.
As developing excellent global leaders should be an urgent priority of companies in the global business world, there has been considerable research in this area. Despite this, there is limited research on the systematic global leadership competency structure reflecting both on its levels and dimensions and on specific competencies. The purpose of this article is to create a theory-based integrative framework that can be used to identify the competencies comprising global leadership. To accomplish this purpose, an integrative literature review was employed on competency theory and global leadership, resulting in the development of an integrative framework for global leadership competency. The framework, with three levels and four dimensions, established in this article contributes to corporations in providing a means of developing company-specific models of global leadership competency. Also discussed are implications for future human resource development research and theory building.  相似文献   
827.
目的观察阿卡波糖对老年糖耐量减低患者颈动脉内中膜厚度的影响。方法120例老年糖耐量减低患者分为两组:60例口服阿卡波糖50 mg,3次·d-1,持续1年,60例未服药,均随访1年。结果治疗后4周患者口服馒头餐后2 h血糖明显下降(P<0.01);1年后治疗组患者HbA1c明显减低(P<0.05),平均颈动脉内中膜厚度增加治疗组明显低于对照组(P<0.05)。结论阿卡波糖有效降低糖耐量减低患者餐后血糖,长期治疗可降低糖化血红蛋白,减缓动脉粥样硬化的发展。  相似文献   
828.
In this paper, we establish some Pitman closeness results concerning the sample median from a symmetric continuous distribution. We show that when an odd sample size is increased by one, the sample median becomes Pitman-closer to the population median, while when an even sample size is increased by one, the sample median need not be Pitman-closer. We establish the former through probabilistic derivations while the latter is through a counterexample. We also discuss the situation when the sample is increased by two observations.  相似文献   
829.
Small area estimation is studied under a nested error linear regression model with area level covariate subject to measurement error. Ghosh and Sinha (2007) obtained a pseudo-Bayes (PB) predictor of a small area mean and a corresponding pseudo-empirical Bayes (PEB) predictor, using the sample means of the observed covariate values to estimate the true covariate values. In this paper, we first derive an efficient PB predictor by using all the available data to estimate true covariate values. We then obtain a corresponding PEB predictor and show that it is asymptotically “optimal”. In addition, we employ a jackknife method to estimate the mean squared prediction error (MSPE) of the PEB predictor. Finally, we report the results of a simulation study on the performance of our PEB predictor and associated jackknife MSPE estimator. Our results show that the proposed PEB predictor can lead to significant gain in efficiency over the previously proposed PEB predictor. Area level models are also studied.  相似文献   
830.
In this paper, we consider estimation of the mean squared prediction error (MSPE) of the best linear predictor of (possibly) nonlinear functions of finitely many future observations in a stationary time series. We develop a resampling methodology for estimating the MSPE when the unknown parameters in the best linear predictor are estimated. Further, we propose a bias corrected MSPE estimator based on the bootstrap and establish its second order accuracy. Finite sample properties of the method are investigated through a simulation study.  相似文献   
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