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51.
徐鹏 《科技广场》2011,(1):42-44
机器人技术作为20世纪自动控制领域的一项伟大成就已经取得了长足的发展,移动机器人也越来越多地应用到了各个行业中。移动机器人具有高度自规划、自组织和自适应能力,适合工作于复杂的非结构化环境中。本文以自主移动机器人为背景,着重对其关键的路径规划技术进行研究和探讨。  相似文献   
52.
以网损最小为目标函数,节点电压、网络辐射性和电源容量的限制为约束条件,建立了配电网络重构优化数学模型。针对各种单一算法的局限性,提出了一种基于链式遗传-模拟退火算法。该算法将环境压力映射为待优化问题,进化链(食物链)上每条染色体(个体)则对应问题的一个候选解,通过模拟退火Metropolis取舍准则控制算法搜索最优方案的进程。最后,在IEEE16节点系统上验证了所提方法的有效性。  相似文献   
53.
A great deal of attention has been paid to design and optimization of low-temperature liquefaction and gas separation problems over the past years, due to their difficult nature. In this paper, two approaches featuring sequential and simultaneous methods for selection and arrangement of sub-ambient separation systems and their associated refrigeration cycles are compared. The effect of ignoring heat integration within the separation system and between the separation and refrigeration systems is addressed as well as fixing the sequence order of separation. The optimization is carried out using two famous stochastic search methods i.e. Genetic Algorithm (GA) and Simulated Annealing (SA). Three case studies are examined to illustrate the significant differences between optimization results. Also, the design optimality is re-checked with respect to usage of different refrigerants and the resulting structure is verified by application of a comprehensive exergy analysis.  相似文献   
54.
The K-means algorithm is one of the most popular techniques in clustering. Nevertheless, the performance of the K- means algorithm depends highly on initial cluster centers and converges to local minima. This paper proposes a hybrid evolutionary programming based clustering algorithm, called PSO-SA, by combining particle swarm optimization (PSO) and simulated annealing (SA). The basic idea is to search around the global solution by SA and to increase the information exchange among particles using a mutation operator to escape local optima. Three datasets, Iris, Wisconsin Breast Cancer, and Ripley's Glass, have been considered to show the effectiveness of the proposed clustering algorithm in providing optimal clusters. The simulation results show that the PSO-SA clustering algorithm not only has a better response but also converges more quickly than the K-means, PSO, and SA algorithms.  相似文献   
55.
对空间数据挖掘聚类技术及其在公共设施选址方面的传统应用方法进行了综述,分析了传统应用方法中有待解决的关键问题,对空间距离代价的表示问题和传统方法的算法时间复杂度进行了初步探讨,运用模拟退火算法和图论对传统方法进行了改进,实现了算法时间复杂度的降低和聚类结果的优化。  相似文献   
56.
文化自信是一个民族、一个国家以及一个政党对自身文化价值的充分肯定和积极践行,并对其文化的生命力持有的坚定信心。本文以文化自信视角,从旅游类核心课程“模拟导游”出发,对其实施意义、实施现状进行数据分析,找出问题,并试图从教学内容、教学方法和考核方式三个方面构建“文化自信”理论下的课程教学模式。  相似文献   
57.
“作业成本法”具有能够准确分析客户成本信息的优点,本文简要阐释了这种分析方法,并在此基础上提出如何运用此方法对客户进行分类管理。  相似文献   
58.
A simulated moving bed (SMB), equipped with eight silica-gel columns, was used to separate phosphatidylcholine (PC) from soybean phospholipids. The effects of flow rate in Sections 2 (Q2) and 3 (Q3), switching time, feed flow rate and feed concentration on the operating performance parameters: purity, recovery, productivity and desorbent consumption were studied. Operating conditions leading to more than 90% purity in both outlet streams have been identified, together with those achieving optimal performance. Regions leading to complete separation are observed and explained theoretically. As the mass-transfer effect was not considered, the triangle theory only gives initial guesses for the optimal operating conditions.  相似文献   
59.
《普罗米修斯》2012,30(2):145-160

Patients and carers now have unprecedented access to health information via specialist journals and the popular media, while the worldwide web has revolutionised public access to clinical information. Levels of patient demand for information about health have grown and there is evidence to suggest that patients wish to receive more information than is sometimes currently provided by clinicians. In secondary care, some specialisms have more readily adopted the use of information communication technologies (ICT) in clinician/patient communication than others. This paper focuses on clinicians' perceptions of client Internet use for psychiatric conditions and studies the influence this has had on the consultation process in the United Kingdom. The research method consisted of a postal questionnaire distributed to the members of the Women in Psychiatry Group on the register of the Royal College of Psychiatry. Telephone interviews were conducted, employing the critical incident method, as well as a brief additional questionnaire. The data show that psychiatrists who used the Internet discerned client usage more readily. Where the client sought to discuss information acquired electronically with the consultant this tended to extend the consultation period, but a number of psychiatrists reported a greater sense of partnership as a result. The paper explores consultant perceptions of client motivations for Internet use and the perceived advantages and disadvantages for both client and psychiatrist. Overall, the psychiatry profession appears to be following the lead of clients in the use of ICT. Policy recommendations are offered with respect to the provision of profession-validated information on the Internet and psychiatrists' training in IT.  相似文献   
60.
A progressive attempt to replace traditional public administration values and concepts by others that are closer to private management can be observed in the replacement of the service user concept by that of consumer or client. This redefinition's more implicit or explicit intent is to increase consumers'/clients' status, their capacity to choose and make rational choices in the market, and, ultimately, to ensure that organisations fulfil their needs. Influenced by this tendency, higher education institutions (HEIs) also started to see students as clients or consumers and to influence their choices by trying to define HE demand. This is evident in the shift in their external communication strategies: ‘institutional information’, based on HEIs' prestige, is being progressively replaced by ‘marketed information’, based on economic consumer logic. In trying to understand how students are perceived by Portuguese HEIs, we undertook qualitative research based on the content analysis of undergraduate degrees' announcements in newspapers. Major findings evidence that their content: (1) can be classified in a continuum bounded by two poles: the use of ‘institutional information’ and the use of ‘marketed information’; (2) show the presence of a social representation of students as clients or consumers; (3) seems related to HEIs' nature (public vs. private), positioning in the HE system (universities and polytechnics) and ‘symbolic capital’ (traditional vs. new institutions).  相似文献   
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