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991.
Abstract

This paper is organized into two main sections. The first section examines extension as an engine for innovation and reviews the numerous priorities confronting extension systems. Section two highlights the current knowledge imperative and the critical connection of extension to post-secondary higher education and training, organizational inservice training, and vocationally oriented self-directed learning. Final comments address ‘The Continuing Role of the Public Sector’, and the prospect of its role in balancing societal interests and promoting extension as an aspect of a knowledge economy. The conclusion proposes what may be agricultural extension's challenges ahead.  相似文献   
992.
Abstract

Purpose: To identify and review production and marketing information sources and flows for smallholder cashew (Anacardium occidentale L.) growers in Tanzania and recommend systems improvements for better technology uptake.

Design/methodology/approach: Two-stage purposive samples were drawn. First, two districts in the main cashew producing areas, one with significant research investment and good marketing infrastructure and the other a counterfactual. Second, two villages were purposively selected from each district to provide the maximum contrast of variables pertinent to the study. Field data were collected using a semi-structured, open-ended questionnaire complimented by field verification and a wrap-up stakeholders' workshop. The data were analysed using chi-square test and the orderly probit model.

Findings: Sources of information and flows varied between districts and villages. For production, the most reliable sources were role model farmers (RMFs), extensionists, radio, on-farm demonstrations, researchers, cashew development centres (CDCs), print media and mobile phones in order of popularity. RMFs, radio programmes, extensionists, interactions with researchers, CDCs and print were the main pathways. For marketing, primary society notice boards, radio announcements, RMFs, extensionists, mobile phones and print were listed in order of popularity. Print media was the least popular due to a low level of literacy among growers. RMFs were popular actors in the information systems irrespective of social-economic background.

Practical implications: Policy change and additional resources are required for improvement of existing information systems. Additionally, incentive structures that will enhance and sustain continued investment in cashew production should be emphasized.

Originality and value: This is the first attempt in the Tanzanian cashew sector to analyse and link social economics of growers with information sources, communication channels and technology uptake.  相似文献   
993.
Abstract

The aim of this study, carried out in association with beef cattle producers, was to explore the capacity of farms to adapt, from a techno-conomic point of view, to both structural changes in consumer demand for beef products and market disruptions (sudden drop in beef consumption due partly to media coverage of bovine spongiform encephalopathy [BSE] and foot-and-mouth disease in the winter 2000/2001). The aim is to help farmers and advisors to find solutions to fit farmers’ management choices with their strategic objectives. The flexibility concept was adopted in order to examine how farms reacted to the winter 2000/2001 crisis, and was based on several technical, economic and sociological surveys. A series of variables was proposed and several hypotheses were formulated regarding their impact on farm flexibility. Four types of farm strategy were identified using different combinations of the degree of importance of these variables, with technical, economic and marketing flexibilities specific to each type. The results revealed the different combinations of flexibility-types possible (technical, economic, marketing) and explain why cattle farmers reacted as they did. Analysis of farm flexibility also revealed situations where these technical, economic and marketing flexibilities were either complementary or incompatible. For traditional livestock farmers, high flexibility (technical and economic) allowed them to minimize the impact of the crisis on their systems. In other cases, low flexibility either resulted in inertia, or led farmers to react by seeking solutions outside the cattle farming system. Development groups should take into account these parameters when interacting with farmers. We propose a framework to qualify the use of information resources by farmers, relative to their flexibility.  相似文献   
994.
Abstract

Purpose: The fields of competence development and capacity development remain isolated in the scholarship of learning and innovation despite the contemporary focus on innovation systems thinking in agricultural and rural development. This article aims to address whether and how crossing the conventional boundaries of these two fields provide new directions for developing learning and innovation competence in international development.

Design/methodology/approach: Using mixed methods research, this article assesses work environments for experiential learning and innovation, and investigates effective ways of enhancing core competence in agricultural research, education, extension and entrepreneurship.

Findings: Findings suggest that while the focus on input and output indicators are relevant for technological innovation competence development, outcome indicators, such as measures of changes in cognitive, affective and psychomotor domains of learning and innovation, would better serve the purpose of developing organisational and institutional learning and innovation competence.

Practical implications: This research concludes that crossing the conventional boundaries of competence development and capacity development serves as a way to renew the role of education within the innovation systems thinking. However, such an attempt to enhance human capabilities and functionings through education should integrate theory-based, competence-based and experiential learning components as a coherent whole.

Originality/value: This article demonstrates the value of crossing the conventional boundaries of the two seemingly unrelated fields—competence development through education and capacity development through extension—to provide new directions to operationalise innovation systems thinking in agricultural education and extension.  相似文献   
995.
系统观是绩效技术整个知识体系的指导原则,系统观也是绩效改进方案在组织中成功实施的关键。绩效技术专家朗姆勒博士正是这样一位秉持系统观,对组织的系统进行层层透视的杰出贡献者。文章在分析了系统观对于绩效技术领域的意义的基础上,分别从朗姆勒的理论和实践两方面介绍他对于绩效技术领域的突出贡献,以期能给与在绩效技术之路上探索的教育技术界同仁些许启发。  相似文献   
996.
研究二阶系统的周期解的存在性。通过使用最小作用原理获得一个新的存在性定理。  相似文献   
997.
针对一类具有饱和非线性输入的混沌系统,基于RBF神经网络的逼近能力提出一种控制方案。该方法利用自适应控制和鲁棒控制,使系统可在模型函数和外扰未知下,设计出结构简单有效的控制器,有效消除了现实中由于饱和非线性输入的存在而引起的控制器抖动的不良控制效果。仿真结果表明了所提控制方法的可行性。  相似文献   
998.
在国家大力推进城乡医院对口支援的大背景下,对城乡医院帮扶机制的概念进行了解析,并以系统论为视角讨论了城乡医院帮扶机制的构建理论,提出了由七要素所构成的城乡医院帮扶机制整体框架,探讨了城乡医院帮扶机制的整体性、层次性和开放性等。在此基础上,应用所构建的城乡医院帮扶机制系统理论对丽水市中心医院的帮扶机制进行了案例分析,详细阐述了现有帮扶机制中的闪光点和短板。最后还为城乡医院帮扶机制的未来研究指出了方向。  相似文献   
999.
在新的形势下如何激发大学生学习的积极性、主动性和创造性,促进其全面和谐发展,是一个重要的课题。从学校制度文化的角度来看,教师影响、教学制度建设、学校制度建设对促进大学生学习观念的养成,促进大学生全面和谐发展,影响深远。  相似文献   
1000.
20世纪50年代,爱国爱港诗人王一桃在广西从教多年,于80年代末定居香港,现已年近八旬,但他保持高度的政治敏感性和异常旺盛的创作激情,笔耕不辍,佳作迭出。近年又出版了沉甸甸的政治抒情诗集《预言和创举》。全书分为冬之卷、春之卷、夏之卷、秋之卷四大卷,别有创意,既有时序更替的本意,更有政治风云变幻的象征。诗集立意高远,气度不凡;政论和诗水乳交融,诗情格调骤然飞升;语言阳刚落地有声,韵律柔美彩色生辉。诗人纵情讴歌了中国特色社会主义如画如诗的美好前景。  相似文献   
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