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Wes Jackson 《Public Library Quarterly》2013,32(1):76-79
In this letter, the director of the Institute, Wes Jackson, contrasts the agriculture he sees in a nearby cultivated field versus the agriculture that Americans need to sustain farm land and the human food supply. Jackson suggests that “a new agriculture” is the only way we will improve the quality of our land and increase the reliability of our food supply. 相似文献
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The purpose of this article and the special issue is to improve our understanding of the theoretical, managerial, and policy implications of entrepreneurial innovation. We accomplish this objective by examining the role of context in stimulating such activity, as well as its impact on the outcomes of entrepreneurial innovation. Our analysis begins by outlining an overarching framework for entrepreneurial innovation and context. With reference to this framework we then compare the attributes of national innovation systems, entrepreneurship and entrepreneurial innovation, and categorize contextual influences on entrepreneurial innovation. We then situate the papers presented in this special issue within this framework. We conclude by outlining an agenda for additional research on this topic, focusing on the relationships between contexts and entrepreneurial innovation and then discuss policy implications, focusing on how public and private actors can meet these challenges. 相似文献
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《International Journal of Information Management》2016,36(1):44-59
Platform-centric ecosystems run by Apple, Google, Microsoft, etc. enable the companies to magnify the values of their products and services on an unprecedented scale, by harnessing third-party add-on software such as mobile apps. Despite the importance, however, there is a dearth of empirical research that investigates how third-party developers’ continued participation is actually determined. This paper examined two different mechanisms increasing dedication to a platform and constraining exit from the platform, respectively. Specific factors in each mechanism and their casual relationships were tested and discussed in the context of Apple’s mobile platform. 相似文献
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基于智力生态系统的研究生创新培养机制研究 总被引：1，自引：0，他引：1
结合研究型大学的研究生培养要求和创造力研究成果,阐明构建研究生创新培养机制的依据。在此基础上,提出构建创新培养机制的基本方法,即建立研究生创新培养机制的目标系统--智力生态系统。研究了智力生态系统的内涵与组成、教育模式、激励机制;提出了基于智力生态系统的研究生创新培养机制的实现方法,包括创新教学内容、建立导师组互动团队、建立知识创新平台、创建研究生培养过程控制机制、创造良好的生活环境、建立国际互访和联合培养制度等。在智力生态系统的运行中贯穿着对研究生进行以人为本的个性化培养模式的探究,以期实现现代研究型大学科技创新和人才培养的可持续发展。 相似文献
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作者对西部干旱地区\"四河四域\"(黄河宁蒙段、石羊河、黑河、塔里木河)的水问题进行了调研,涉及其上中下游的历史背景与现状,包括水资源、水灾害、水生态、水污染;水工程、节水技术、水景观;水制度、水经济、水伦理、水美学,认为:西部干旱地区水问题主要不是自然原因,而是人类因素造成的。根据\"生态水利\"观,就广义\"水资源\"概念,自然生态用水定额,干旱地区的经济结构和城镇建设模式,恢复、保护和创造性利用内陆河下游自然生态系统,节水行动和技术的新方向,与干旱地区自然环境和生态特点相适应的水利工程,完备水制度以及人工调水等8个方面,提出了建议。 相似文献
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Megan Powell Cuzzolino Tina A. Grotzer M. Shane Tutwiler Eric W. Torres 《科学教学研究杂志》2019,56(8):1083-1105
Agent-oriented pedagogies have been used in teaching concepts related to complex systems dynamics. However, little research has systematically explored the role of a strong agency-oriented focus on understanding of complex, dynamic ecological systems. This study analyzed seventh graders' (n = 216) explanations of a complex ecological scenario. The findings show that students were more likely to generate agentive than nonagentive explanations and students who adopted an agentive framing were least likely to understand the complex causal dynamics of two environmental scenarios, eutrophication in a pond and acid rain in a forest. Furthermore, students' initial inclination toward agency-oriented explanation on the assessment was predictive of their performance on a postassessment following an instructional opportunity to learn about ecosystems dynamics; a strong agency orientation corresponded to less complex interpretations of the dynamics of the ecosystems. The results suggest that a strongly agentive perspective may limit students' ability to learn complex systems dynamics and that the pedagogical advantages of agent-based approaches may not be without limitations. 相似文献
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区域性农田景观对昆虫的生态学效应与展望 总被引：1，自引：0，他引：1
有害生物的生态调控一直是作物病虫害预防与治理的重要前沿科技领域。目前有害生物生态调控研究已由单一的农田拓展到区域性农田景观的空间范围。研究区域性农田景观中格局特征和人类活动对病虫害和天敌种群动态影响,不仅在病虫害生物防治的实践中有重要意义,而且对于揭示人类活动对生物多样性结构与功能的影响,阐明区域性农田景观中生物多样性整合、维持机理有重大的理论意义。作物病虫害的导向性防控——生物间信息流与行为操纵,最终需要体现和落实在特定的地理区域空间范围内,参与到粮食作物生产与病虫害生态管理活动过程中。文章主要阐述区域性农田景观中格局特征与人类种植活动对昆虫的生态学效应,并提出构建基于区域性农田景观多元化的有害生物生态调控体系。 相似文献