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基于PSO和滚动优化的不确定环境下移动机器人动态路径规划 总被引：1，自引：0，他引：1
针对全局环境未知且存在动态障碍物情况下的移动机器人路径规划问题,本文提出了一种结合粒子群算法(PSO)和滚动优化策略的动态路径规划方法。通过在一系列移动空间窗口中进行在线规划来充分利用机器人实时测得的局部环境信息,并用粒子群算法求解每一个移动窗口内的最优路径。为及时躲避动态障碍物,提出了一种适用于动态未知环境下的适应度函数。仿真试验表明,该方法克服了现有局部路径规划方法的高复杂性的缺点,算法操作简单、具有全局寻优能力、收敛速度快、鲁棒性好,可以满足机器人在复杂的未知动态环境下路径规划的实时性要求。 相似文献
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利用蚁群算法对于空域内复杂环境下飞行冲突进行路径规划与动态防撞的预测算法。该算法模拟蚂蚁的觅食行为,利用多组机器蚂蚁采用局部搜索策略和趋近导向函数方法完成全局最优路径搜索,可以利用虚拟蚂蚁代替飞机作碰撞的预测,理论和仿真实验结果说明在多机冲突环境中能够迅速规划出优化路径,防止飞机间的相互碰撞。 相似文献
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【目的/意义】通过对我国省域数字政府高质量建设的政策驱动路径进行分析，有利于丰富和完善我国数字政府政策的内部协同机制，可在政策层面为我国政府的数字化转型工作提供决策支持。【方法/过程】选取我国31个省级行政区政府已经出台的76份政策文本，采用内容分析法，借助NVivo12软件，基于政策工具视角对政策文本进行量化分析；根据量化分析结果选取典型的政策工具类型，采用模糊集定性比较分析（fsQCA）方法揭示政策工具的不同组合与数字政府高质量建设间的因果关系，分析我国省域数字政府高质量建设的政策驱动路径。【结果/结论】单一政策工具不能构成数字政府高质量建设的必要条件。数字政府高质量建设的驱动路径有四种类型（包括7条不同的组态路径），分别是供给型路径、环境型路径、供给-环境协同型路径和供需-环境协同型路径。【创新/局限】将内容分析法与fsQCA方法相结合，构建了政策工具视角下省域数字政府高质量建设驱动路径的理论分析框架。但研究结论有待获取更多维度、更细粒度的主客观实证数据进行实践检验，未来还可以考虑通过采集面板数据进行动态QCA组态分析。 相似文献
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[目的/意义]主路径上核心主题的演化可以反映行业发展方向，凸显行业热点技术并预测技术的未来发展，有效判断技术主题间的传承演变关系。[方法/过程]本研究构建一种凸显主路径上的核心主题及演化方法。该方法不同于文本挖掘和聚类，是基于引文网络主路径映射专利分类号的链接计数，通过专利的分类号替代技术主题在主路径上演化并计算节点的技术主题含量，以技术主题含量的变化凸显主路径上的核心主题及其发展历程。[结果/结论]展示有机发光二极管OLED的主题演化图，证实了该方法的合理性。 相似文献
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TSP问题茁物流配送、选址等领域普遍存在，是当前相关领域研究的热点问题。本文提出在WebGIS环境下，利用遗传算法表求解该问题．首先，针对WebGIS数据，以实际地标经纬度信息作为初始点，提取路网拓扑结构，然后使用遗传算法采求解哈密顿路开最终给出优化路径。实验结装表明提出的方法具有良好的实际应用效果。 相似文献
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本文采用栅格法建立机器人的环境模型,把免疫算法应用到机器人的路径规划中,通过提出一种新的多因素适应度函数,使对个体的评估更符合机器人所需要的最优路径。仿真结果表明该方法可行,而且有效,可以提高收敛速度,并与遗传算法进行比较,发现使用该免疫算法解决了遗传算法后期的波动现象。 相似文献
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【目的/意义】在国际政治经济环境和全球创新格局不断变化的背景下，拓展全球科技创新合作伙伴、建立更为广泛和紧密的全球科技创新合作网络，成为亟待解决的问题。【方法/过程】本文基于科技论文构建主题词共现矩阵，筛选二阶共现主题词对作为潜在国际科技合作主题对，通过定义主题对的国际合作潜力指数以及主题路径的国际科技合作路径强度指数，判定主题对的国际合作潜力并寻找有效的主题合作路径。【结果/结论】以中俄人工智能领域的SCI论文和CPCI-S论文为分析对象，通过对该领域潜在国际科技合作主题的识别和分析，证实本文所提方法的有效性。【创新/局限】本文提出一种识别潜在国际科技合作主题的方法，并利用中俄两国论文进行实证研究，但未考虑不同国家研究产出规模差异，未对关键词进行语义分析，需在后续研究中进一步探讨。 相似文献
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面向突发事件和危机的企业管理新路径 总被引：2，自引：1，他引：2
当代企业面临的环境更趋动态、复杂,突发事件和危机不可避免,然而现有管理理论和方法没能提供较为系统、有效的应对路径。社会资本理论提供了应对突发事件与危机的新视角,通过社会组织治理实现社会资本结构与质量的不断优化是该视角下企业应对突发事件和危机的新路径,IESS模型和SOCA框架为此新路径提供了理论工具和操作指南。 相似文献
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A research group led by Prof. ZHAI Qiwei from the Institute for Nutritional Sciences under the CAS Shanghai Institutes for Biological Sciences has discovered that even relatively low doses of resveratrol-a chemical found in the skins of red grapes in red wine-can improve the sensitivity of mice to the hormone insulin according to a report in the October issue of Cell Metabolism.…… 《中国科学院院刊(英文版)》2008,22(1):14-15
Aresearch group led by Prof. ZHAI Qiwei from the Institute for Nutritional Sciences under the CAS Shanghai Institutes for Biological Sciences has discovered that even relatively low doses of resveratrol--a chemical found in the skins of red grapes and in red wine--can improve the sensitivity of mice to the hormone insulin, according to a report in the October,2007 issue of Cell Metabolism. As insulin resistance is often characterized as the most critical factor contributing to the development of Type 2 diabetes, the findings“provide a potential new therapeutic approach for preventing or treating” both conditions, the researchers said. 相似文献
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Marjorie Armstrong-Stassen Margaret Landstrom Ramona Lumpkin 《The Information Society》1998,14(2):153-164
This study examined how students who had no prior experience with videoconferencing would react to the use of videoconferencing as an instructional medium. Students enrolled in seven different courses completed a questionnaire at the beginning of the semester and again at the end of the semester. Students at the origination and remote sites did not differ in their reactions toward videoconferencing but there was a significant difference for gender. Women reacted less favorably to videoconferencing. Compared to the beginning of the semester, students reported significantly less positive attitudes toward taking a course through videoconferencing at the end of the semester. There were no significant differences in students' attitudes toward videoconferencing across courses at the beginning of the semester but there were significant differences across the courses at the end of the semester. The results suggest the need for better preparation for both students and instructors. 相似文献
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A joint study by Prof. ZHANG Zhibin from the CAS Institute of Zoology his co-workers from Norway US Swiss have indicated that historical outbreaks of migratory locusts in China were associated with cold spells suggesting that China's projected climate warming could decrease the pest's numbers. The study was published in Proceedings of the National Academy of Sciences on September .…… 《中国科学院院刊(英文版)》2008,22(1):6-7
Ajoint study by Prof. ZHANG Zhibin from the CAS Institute of Zoology and his co-workers from Norway, US and Swiss have indicated that historical outbreaks of migratory locusts in China were associated with cold spells, suggesting that China＇s projected climate warming could decrease the pest＇s numbers. The study was published in Proceedings of theNational Academy of Sciences on 17 September, 2007. 相似文献
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Caroline Haythornthwaite 《The Information Society》2001,17(3):211-226
A computer-mediated group is a complex entity whose members exchange many types of information via multiple means of communication in pursuit of goals specific to their environment. Over time, they coordinate technical features of media with locally enacted use to achieve a viable working arrangement. To explore this complex interaction, a case study is presented of the social networks of interactions and media use among members of a class of computer-supported distance learners. Results show how group structures associated with project teams dominated who communicated with whom, about what, and via which media over the term, and how media came to occupy their own communication niches: Webboard for diffuse class-wide communication; Internet Relay Chat more to named others but still for general communication across the class; and e-mail primarily for intrateam communication. Face-to-face interaction, occurring only during a short on-campus session, appears to have had a catalytic effect on social and emotional exchanges. Results suggest the need to structure exchanges to balance class-wide sharing of ideas with subgroup interactions that facilitate project completion, and to provide media that support these two modes of interaction. 相似文献
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Active biological molecules functional structures can be fabricated into a bio-mimetic system by using molecular assembly method. Such materials can be used for the drug delivery disease diagnosis therapy new nanodevice construction.…… 《中国科学院院刊(英文版)》2008,22(1):22-22
Active biological molecules and functional structures can be fabricated into a bio-mimetic system by using molecular assembly method. Such materials can be used for the drug delivery, disease diagnosis and therapy, and new nanodevice construction. 相似文献
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《中国科学院院刊(英文版)》2008,22(1):2-3
CAS should stick to the principle of rendering service to, and giving impetus for, the development of China＇s science enterprise by making S＆T innovations, said CAS President LU Yongxiang. The CAS president made the remarks in a recent talk to communicate the gist of the winter session of the Party＇s Leading-member Group at CAS, which was held from 7 to 11 January in Beijing. 相似文献
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《中国科学院院刊(英文版)》2008,22(1)
With great care, Dr. ZHOU Zhonghe takes out a package wrapped by cotton tissue from a drawer and says: "This is the gem of our collections: the fossil of a bird that lived 125 million years ago!" Then, pointing at a tiny mound, he explains: "Look, this is the claw and that is the head. It was in the egg shell and ready to hatch ... The species fell into a family of waterside inhabitants." 相似文献
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Electronic data interchange (EDI) provides means for interorganizational communication, creates network externalities, requires an advanced information technology (IT) infrastructure, and relies on standards. In the diffusion of such innovations, institutional involvement is imperative. Such institutions contain governmental agencies, national and global standardization organizations, local government, and nonprofit private organizations like industry associations. The last type of organizations we call intermediating institutions. They intermediate or coordinate ("inscribe") the activities of a group of would-be adopters. Unfortunately, little is known of how these organizations shape the EDI diffusion trajectory. In this article we examine one specific type of intermediating organizations?industry associations?and how they advanced the EDI diffusion process in the grocery sectors of Hong Kong, Denmark and Finland. We identify six institutional measures, placed into a matrix formed by the mode of involvement (influence vs. regulation) and the type of diffusion force (supply push vs. demand pull), that can be mobilized to further the EDI diffusion. Industry associations were found to be active users of all these measures to varying degrees. Their role was critical especially in knowledge building, knowledge deployment, and standard setting. Furthermore, institutional involvement varied due to policy and cultural contingencies and power dependencies. 相似文献
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Leah A. Lievrouw 《The Information Society》2000,16(2):155-159
This essay focuses on universal service and the Internet as means to support social and political participation. The emphasis on access to telecommunications systems in conventional approaches to universal service is contrasted with access to content. A model of the information environment is described that accounts for the roles of content and conduit, both of which are necessary conditions to achieve true access. A method is outlined for employing information indicators to observe or measure the information environment. 相似文献
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Puay Tang 《The Information Society》1998,14(1):19-31
The increasing prospects of digital piracy has prompted the perceived need by electronic publishers to adopt technical systems of protection, and governments to reform their copyright laws. This article is a preliminary study of the management of intellectual property by electronic publishers, defined as those involved in the production of online databases, and CD-ROMs. It focuses on three main issues: (1) how electronic publishers view the increasing threat of piracy; (2) the methods of protection employed to protect intellectual property in digital format; and (3) the importance of technological protection of intellectual property in electronic publications. The analysis is based on a sample of 23 UK electronic publishers. The interviews revealed an interesting assortment of protection methods and did not show that technological protection was a preferred way. Instead, the means of protection, in addition to copyright law, comprised niche markets, pricing, trust, bad publicity, and nontechnical and technical means. 相似文献