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41.
Farhad Mirzaei 《The Journal of Agricultural Education and Extension》2013,19(3):321-323
Abstract The paper explores the difficulties and challenges in mobilizing and managing social capital in concrete local and territorial directed rural development project activities. The main focus is put on the roles of local facilitators working with farmers and other local stakeholders during project implementation. The EU 5th framework project IMALP included a strong component of implementing concrete actions. In each of the four participating countries a region was selected where a so-called local group was established. A local facilitator was employed to moderate the local group and to assist in the design and implementation of concrete projects. Research accompanied and monitored the process. The recent shift of EU policy towards rural development from a mainly sectoral (agricultural) approach to a territorial approach requires new competences in managing social capital and on their changing role(s) in the different stages of group formation and development. Professional support by facilitators with a set of new skills is needed in the course of group formation and development. The identification, mobilization and management of social capital become a crucial challenge. So far the mobilization and management of social capital does not happen consciously. Agricultural advisors taking over the task of local facilitators need to be specially trained in actively mobilizing and coordinating towards a common goal. The value of the paper lies in the analysis of the experimental approach of the project and the cross-country comparison of the results. 相似文献
42.
In the structures where long-term behavior should be monitored and controlled, creep and shrinkage effects have to be included precisely in the analysis and design procedures. Shrinkage varies with the constituent and mixture proportions, and depends on the curing conditions and the work environment as well. Self-compacting concrete (SCC) contains combinations of various components, such as aggregate, cement, superplasticizer, water-reducing agent and other ingredients which affect the properties of the SCC including shrinkage. Hence, the realistic prediction shrinkage strains of SCC are an important requirement of the design process for this type of concrete structures. This study reviews the accuracy of the conventional concrete (CC) shrinkage prediction models proposed by the international codes of practice, including CEB-FIP (1990), ACI 209R (1997), Eurocode 2 (2001), JSCE (2002), AASHTO (2004; 2007) and AS 3600 (2009). Also, SCC shrinkage prediction models proposed by Poppe and De Schutter (2005), Larson (2007), Cordoba (2007) and Khayat and Long (2010) are reviewed. Further, a new shrinkage prediction model based on the comprehensive analysis on both of the available models, i.e., the CC and the SCC is proposed. The predicted shrinkage strains are compared with the actual measured shrinkage strains in 165 mixtures of SCC and 21 mixtures of CC. 相似文献
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In four experiments, rats were trained on different patterning discriminations before being tested with compounds composed of novel combinations of the trained stimuli. In Experiment 1, rats were trained on a negative-patterning schedule (A+ B+ AB-) intermixed with reinforced presentations of a second compound (CD+). On a subsequent test, the rats responded more to two novel compounds, AC and BD, than to A and B, but less than to CD. In Experiment 2, rats were trained on two concurrent negative-patterning discriminations (A+ B+ AB-, C+ D+ CD-). On test, they responded more to AC and BD than to AB and CD, but less than to the single stimuli. In Experiment 3, rats were trained on two concurrent positive-patterning discriminations (A-B- AB+, C- D- CD+). On test, their response rates to AC and BD were not different from the response rates to the trained compounds (AB and CD). Finally, in Experiment 4, rats were trained on a positive- and negative-patterning discrimination concurrently. Once again, on test, response rates to AC and BD were not different from responding on reinforced trials of the trained discriminations (A+, B+, and CD+). We discuss the implications of these findings for elemental and configural models of stimulus representation. 相似文献
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