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技术演化Logistic模型的扩展:多种技术创新演化的选择过程分析
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作者 陆瑾 《价值工程》 2006年第5期37-39,共3页
典型的技术演化Logistic模型描述的是当存在两种新、旧技术的竞争时,单种创新的技术随时间的演化而扩散演化的轨迹,其缺陷是没有对多种创新技术同时作用进行分析。本文考虑一个改进的创新技术的扩散模型,拓展Logistic模型的解释空间,用... 典型的技术演化Logistic模型描述的是当存在两种新、旧技术的竞争时,单种创新的技术随时间的演化而扩散演化的轨迹,其缺陷是没有对多种创新技术同时作用进行分析。本文考虑一个改进的创新技术的扩散模型,拓展Logistic模型的解释空间,用技术适应度、新技术选择“尝试努力”时所运行的时间、平均尝试次数、“尝试努力”成功次数的平均概率等指标,来考察在一个固定的技术选择空间内,多种技术演化的随机寻优轨迹和寻优难度;从而在一定程度上为拓展技术选择空间引入新技术,不断进行技术创新提供理论解释。 展开更多
关键词 LOGISTIC模型 创新技术扩散 技术适应度 技术选择空间 随机选择
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Rapid satellite-to-site visibility determination based on self-adaptive interpolation technique 被引量:4
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作者 HAN Chao GAO XiaoJie SUN XiuCong 《Science China(Technological Sciences)》 SCIE EI CAS CSCD 2017年第2期264-270,共7页
Rapid satellite-to-site visibility determination is of great significance to coverage analysis of satellite constellations as well as onboard mission planning of autonomous spacecraft. This paper presents a novel self... Rapid satellite-to-site visibility determination is of great significance to coverage analysis of satellite constellations as well as onboard mission planning of autonomous spacecraft. This paper presents a novel self-adaptive Hermite interpolation technique for rapid satellite-to-site visibility determination. Piecewise cubic curves are utilized to approximate the waveform of the visibility function versus time. The fourth-order derivative is used to control the approximation error and to optimize the time step for interpolation. The rise and set times are analytically obtained from the roots of cubic polynomials. To further increase the computational speed, an interval shrinking strategy is adopted via investigating the geometric relationship between the ground viewing cone and the orbit trajectory. Simulation results show a 98% decrease in computation time over the brute force method. The method is suitable for all orbital types and analytical orbit propagators. 展开更多
关键词 satellite-to-site visibility rapid determination self-adaptive Hermite interpolation viewing cone
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