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101.
102.
In January 2004, the National Collaboration for Youth approved a list of core competencies needed by entry-level youth development workers for effective youth development practice. This chapter provides an overview of these competencies, explaining why and how the list was created, outcomes, and recommendations for next steps.  相似文献   
103.
As debates continue over the effectiveness of after-school programs, we need to create stronger links between schools and out-of-school activities. Where do such connections begin? How can we integrate skill-building and academic competence into the out-of-school-time context?  相似文献   
104.
The Accuracy of Respondent-Coded Occupation   总被引:1,自引:0,他引:1  
This study reports results from a methodological experimentconducted in a national survey to test the accuracy of respondent-codedoccupation. For most uses, we conclude that such measures aresufficiently precise. There are, however, some systematic sourcesof error which the investigator should be aware of.  相似文献   
105.
106.
Strong, effective communication may be the single most important key to success for any type of executive. Leaders of health care organizations must be able to promote ideas that others will implement, help staff see the value of their work, and have the vision to overcome limitations that stand in the way of progress.  相似文献   
107.
This simulation study compares three operational measures of performance through the exploration of three work-in-process (WIP) inventory drive systems and their associated inventory buffer characteristics. The three drive systems under study are a push, a pull and a hybrid push-pull system. While these systems have many aspects in common, their buffer management systems do not. The data analysis was based on information gathered from three computer-simulated flow shop assembly lines all operating in the same environment. Hypotheses concerning the operational performance measurements were established, independent variables were controlled and manipulated and a conclusion was drawn as to which system would afford the operation optimum results. While inventory has traditionally been considered and is currently being shown as an asset from an accounting point of view, it is obvious from the findings of this study, that excess WIP inventory, above the minimal requirements for production, may have a negative effect on the operational measurements evaluated.  相似文献   
108.
Protecting riparian corridors is a commonly applied environmental policy in urban landscapes. However, empirical data demonstrating their efficacy for biodiversity conservation outcomes is scarce. In this study we investigated whether riparian corridor width influences the diversity and community structure of ant (Hymenoptera: Formicidae) and vascular plant assemblages therein. Eighteen corridors of differing widths were selected from within the Ku-ring-gai Local Government Area, Sydney Australia. Ants were sampled using pitfall traps positioned within rectangular vegetation transects (30 × 10 m). Both ant and plant species richness, when standardised for sampling effort, were unrelated to riparian corridor width. However, significant compositional differences between sites were evident with increased width up to ~50 m. Narrow corridors contained greater abundances of opportunistic ant species and higher proportions of exotic plants. We interpret this to be the result of the greater disturbance/edge influence derived from adjacent upland urban environments. Site beta diversity did not increase with corridor width, suggesting that the exclusion of novel upslope habitats in narrow riparian corridors is not a significant cause of community assemblage modification at these sites. To minimise the impact of deleterious edge effects on ant fauna, environmental managers should seek to retain riparian corridors wider than ~50 m. However, we observed substantial between-site variability of biotic assemblages, irrespective of corridor width. Therefore we recommend that environmental management practice needs to take a catchment-wide approach and consider other parameters that may contribute to riparian health so as to optimise the protection of riparian biodiversity.  相似文献   
109.
Formalized planning is currently applied to planning for operations and capital investment, planning for products and markets, and occasionally for manpower. However, there is little evidence that companies are producing formal plans and programmes to deal with social and political change. Unfortunately, public opinion is moving against business, action groups inside and outside companies are challenging the authority of management, and public officials and politicians are already framing new laws and regulations. Unless managers begin to get more involved in the framing of these controls they are likely to find laws enacted and enforced by people who have little knowledge or sympathy with business. In this article the author points up the necessity to assess the social and political challenge to their business, and formulate and implement social and political strategies and plans aimed at ensuring the survival and prosperity of their organisations.  相似文献   
110.
SUMMARY A novel proposal for combining forecast distributions is to use quantile regression to combine quantile estimates. We consider the usefulness of the resultant linear combining weights. If the quantile estimates are unbiased, then there is strong intuitive appeal for omitting the constant and constraining the weights to sum to unity in the quantile regression. However, we show that suppressing the constant renders one of the main attractive features of quantile regression invalid. We establish necessary and sufficient conditions for unbiasedness of a quantile estimate, and show that a combination with zero constant and weights that sum to unity is not necessarily unbiased.  相似文献   
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