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Toward Modelling of Transformational Change Processes in Farm Decision-Making
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作者 S. Huet C. Rigolot +2 位作者 q. xu Y. De Cacqueray-Valmenier I. Boisdon 《Agricultural Sciences》 2018年第3期340-350,共11页
In the coming decades, agricultural systems will have to adapt to tremendous challenges. Behavioral models have important potential to better understand and steer changes toward sustainability brought about by this co... In the coming decades, agricultural systems will have to adapt to tremendous challenges. Behavioral models have important potential to better understand and steer changes toward sustainability brought about by this context. Relying on a literature review, we distinguish incremental changes (extensions of what is already done) and transformational changes, which involve the reorientation of a considerable amount of farming activities. Transformational changes are particularly important in the context of global change. Existing integrated modelling frameworks based on behavioral theories are suited for incremental changes, but remain limited for transformational changes. Qualitative studies provide important insights on two key aspects of transformational changes, learning and social relations, but they have not been explicitly oriented toward computer modelling yet. Based on this literature and three seminal decision-making approaches, we propose a description of transformational change processes in farm decision-making, as a first step toward an implementation in agent-based models. 展开更多
关键词 TRANSFORMATION ADAPTATION Modelling DECISION-MAKING FARMER
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Full-band error control and crack-free surface fabrication techniques for ultra-precision fly cutting of large-aperture KDP crystals 被引量:5
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作者 F. H. ZHANG S. F. WANG +2 位作者 C. H. AN J. WANG q. xu 《Frontiers of Mechanical Engineering》 SCIE CSCD 2017年第2期193-202,共10页
Large-aperture potassium dihydrogen phos- phate (KDP) crystals are widely used in the laser path of inertial confinement fusion (ICF) systems. The most common method of manufacturing half-meter KDP crystals is ult... Large-aperture potassium dihydrogen phos- phate (KDP) crystals are widely used in the laser path of inertial confinement fusion (ICF) systems. The most common method of manufacturing half-meter KDP crystals is ultra-precision fly cutting. When processing KDP crystals by ultra-precision fly cutting, the dynamic characteristics of the fly cutting machine and fluctuations in the fly cutting environment are translated into surface errors at different spatial frequency bands. These machin- ing errors should be suppressed effectively to guarantee that KDP crystals meet the full-band machining accuracy specified in the evaluation index. In this study, the anisotropic machinability of KDP crystals and the causes of typical surface errors in ultra-precision fly cutting of the material are investigated. The structures of the fly cutting machine and existing processing parameters are optimized to improve the machined surface quality. The findings are theoretically and practically important in the development of high-energy laser systems in China. 展开更多
关键词 ultra-precision fly cutting large-aperture KDP crystals spatial frequency processing error
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