基于蚁群算法的城市公共自行车调度研究

由于城市公共自行车存在供需时空分布的不均衡性,因而进行公共自行车的调度是十分必要的。通过分析现阶段我国城市公共自行车调度方式特性,为充分满足租赁者的需求,提出了一种带模糊时间窗的城市公共自行车调度路径优化模型。以租赁点满意度最大化为目标函数,同时将基本蚁群算法进行改进后应用于求解最优调度路径模型。最后,以宁波市公共自行车区域调度为例,运用Matlab进行仿真实验,证明了该模型及求解算法的有效性和可行性。     

公共自行车租赁管理系统的设计与实现研究

最近几年,公共租赁自行车在各大城市得到了普及,城市公共交通管理者加大了对其的重视、投入力度。纵观国内外,巴黎、伦敦、北京等发达城市建立了公共自行车租赁系统。公共租赁自行车的存在,既有利于城市公共建设,有利于用户出行。然而,在设计运营系统时,其目标对象为单个区域用户的自行车,且处于封闭状态,存有很多问题,对推广及应用公共自行车租赁具有负面影响。公共自行车租赁业务的不断拓展及使用效益愈来愈大,其对管理系统提出了多区域的要求。     

浅谈公共自行车调度问题

公共自行车是一种创新的公共交通方式,公共自行车在国内已经引起了重视,并且得到了快速的发展。国内外对于公共自行车的研究主要在于租赁点布局,但是对于公共自行车运营、调度问题研究较少。现阶段,国内几大城市存在公共自行车车辆调度难题,文章对于这几个城市车辆调度现状及问题进行深入分析。国外对于公共自行车的研究起源较早,开始集中于公共自行车系统规划、运营以及自行车使用特征调查分析,现阶段已经逐渐转移到调度问题上,国内对于公共自行车调度研究处于起始阶段,规模较小,调配算法研究目前还不是很深入。本文在对国内外对于公共自行车调度研究存在缺陷,进行总结,同时提出创新的调度优化方法。     

基于用户与资源一体化的公共自行车自适应调度模式研究

当前公共自行车已在国内广大城市获得普及使用,然而在各公共自行车租赁点经常出现"无车可借,无处还车"的尴尬局面,究其原因主要是由于自行车使用中存在分布不均匀,调度不及时造成。当前普遍采用的"人工+调度车"的调度模式不能及时感应自行车的分布不均匀性,对自行车损伤较大等问题。为了克服当前自行车调度的不足,本文提出一种基于用户资源一体化的公共自行车自适应调度模式,其应用互联网技术、GPS定位技术、移动通讯技术等实时进行自行车用户、自行车、调度平台三者之间的信息交互,调度平台将各站点历史数据、实时车辆信息和用户出行需求信息在时间和空间上进行动态结合,通过分析各站点实时需求量,利用经济手段通过奖励机制及时而自动的引导用户将自行车停放到合适的地点,从而实现自行车的自适应调度。     

西安自行车租赁系统的问题调查和建议

城市公共自行车,作为公共交通中解决"最后一公里"问题,实现"门对门"服务的新成员,具有经济、环保、灵活、便捷、成本低、占地少等独特优势。通过本次调研发现城市自行车租赁系统的问题,分析人与系统的关系,提出以西安为例的大城市的自行车租赁点规划和设计并提出改进措施。     

农网物资储备点需求趋势优化预测方法

为了提高农网物资储备点的优化管理和调度能力,需要对农网物资储备点的需求趋势进行优化预测,提出基于关联规则调度和模糊自适应聚类的农网物资储备点需求趋势优化预测方法,构建农网物资储备点需求趋势的统计序列分布模型,采用大数据挖掘方法进行农网物资储备点需求趋势的大数据统计信息建模,提取农网物资储备点需求趋势的关联规则特征量,采用模糊聚类方法对需求趋势大数据进行自动聚类处理,建立农网物资储备点需求趋势预测的优化迭代模型,结合自适应寻优算法实现农网物资储备点需求趋势优化预测。仿真结果表明,采用该方法进行农网物资储备点需求趋势预测的自适应性较好,预测精度较高,提高了农网物资储备点的自适应调度和管理能力。     

基于任务聚类策略的云计算资源调度研究

云计算是信息时代的新型的计算模式,代表着下一代的互联网技术。资源调度和管理是云计算的关键技术之一,资源调度的目标包括满足用户服务质量、提高资源利用率、节点负载均衡等,为此有必要借助各种调度策略与各优化算法对资源调度方案进行优化,以提高任务和资源的匹配效率。聚类是将物理或者抽象的对象集合依据相似程度划分为若干类群,源于数学、统计和经济等领域,并广泛应用于很多领域。在云计算资源调度中,用户任务的资源需求特征异同,本文基于相似分治的思想,对用户任务进行聚类处理后优化调度是云计算资源调度研究的一个有效思路。实验仿真表明,任务聚类策略有效地提高了后续任务资源调度优化的效率。     

基于聚类划分的增量式关联规则研究

数据挖掘是目前信息领域和数据库技术领域的前沿研究课题,它涉及到数理统计、模糊理论、神经网络和人工智能等多种技术,技术含量比较高,实现难度也较大.本文研究了关联规则挖掘技术的基本概念、过程和算法等,为提高数据挖掘效率,提出了基于聚类划分的增量式关联规则挖掘算法.即运用快速聚类方法实现数据划分、运用改进的FP-growth算法实现关联规则的挖掘和运用增量FP-growth挖掘算法实现增量数据挖掘的关联规则挖掘算法.     

基于贝叶斯粗糙集的大数据频繁项挖掘技术

对大数据的频繁项集挖掘是关联规则挖掘的关键步骤,通过有效的频繁项挖掘提高大数据量数据库的访问效率。传统方法中对大数据的频繁项集挖掘采用FP-Growth的粗糙集挖掘算法,扩展性和容错性不好。提出一种基于贝叶斯粗糙集的大数据频繁项挖掘技术,引入后缀项表的概念,通过后缀项表的构建,保留频繁项集的完整信息。构建FP-Tree,生成闭频繁项集,计算样本的密度,并抽取高密度区域的点集作为聚类中心集合,进行后缀项表的构造,按支持度分成若干集合,对各约简集内的属性集合进行融合,用变精度粗糙集的贝叶斯粗糙进行数据挖掘算法改进,仿真结果表明,算法不受可变参数的影响,鲁棒性较高,数据挖掘的准确度较高,运行时间较短。算法将在人工智能和数据挖掘领域具有更广的应用前景。     

社会化标注系统中基于关联规则的Tag资源聚类研究

运用关联规则挖掘标签间的相互关系,并结合典型的划分聚类算法k-means进行Tag资源自动聚类,从而实现对Tag资源重新组织,为用户提供更好地标签导航和浏览机制。并利用豆瓣网上的实例数据验证了算法的可行性和有效性。     

Students' Reactions to the Introduction of Videoconferencing for Classroom Instruction

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.     

Cooler temperatures inductive to locust outbreaks

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.     

Exploring Multiplexity: Social Network Structures in a Computer-Supported Distance Learning Class

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.     

The Role of Intermediating Institutions in the Diffusion of Electronic Data Interchange (EDI): How Industry Associations Intervened in Denmark, Finland, and Hong Kong

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.     

How Electronic Publishers are Protecting Against Piracy: Doubts About Technical Systems of Protection

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.     

Rough Justice: A Statistical Assessment of ICANN's Uniform Dispute Resolution Policy

Long-standing conflict between domain name registrants and trademark holders prompted the Internet Corporation for Assigned Names and Numbers (ICANN) to create a global, mandatory arbitration procedure known as the Uniform Dispute Resolution Policy (UDRP). The UDRP has been used in 2166 cases involving 3938 domain names as of 1 November 2000. The policy gives the initiator of a complaint, generally a trademark holder, the right to choose which ICANN-accredited dispute resolution service provider (RSP) will handle the case. During the preparation of the UDRP,some feared that complainant selection would lead to "forum shopping" that might bias the results. This article performs a statistical assessment of the forum-shopping thesis and finds support for it. There are statistically significant differences in the various RSPs' propensity to take away names from defendants; there are also major differences in the number of cases brought to each RSP. RSPs who take away names have the larger share of cases. The study examines other variables that might explain differences in market share, such as price, the plaintiff's nationality, or the time taken to decide a case. It finds that nationality and time also are correlated with market share. The study concludes that shopping for a favorable outcome is an important factor in the UDRP.     

Prevalence of soft neurological signs in Chinese people

Prof. Raymond C.K. Chen, a neuropsychologist with the CAS Institute of Psychology, has made novel progress in his studies of schizophrenia. His work has been reported by a recent issue of Behavioural Neurology.     

Monoculture Rubber Plantations Have Negative Ef ects on Controlling Splash Erosion

<正>In Xishuangbanna,one of China’s most biodiverse regions,landscape has changed dramatically during the past three decades due to the conversion of tropical rainforest to rubber plantations.In steep areas,terraces are often constructed before planting rubber trees,which causes two important changes in the soil:the destabilization of soil in the bench terraces and the increased vulnerability of unvegetated riser faces to erosion.Few studies have documented the nature and intensity of erosion on bench terraces.Prof.LIU Wenjie and his colleagues from the Xishuangbanna Tropical Botanical Garden(XTBG)conducted a study in Menglun County(21°5′39″N,101°15′55″E),Xishuangbanna to evaluate the influence     

Chinese Scientists Use Earth Observation Technologies to Study and Protect Wild Camels

<正>Chinese scientists plan to apply Earth Observation technologies to protect the critically endangered wild camels(Camelus ferus).With the help of remote sensing,satellite positioning,geographical information system and wireless sensors networks,they will be able to access the distribution and population of the wild camels and protect their habitats.The project will be carried out by the International Research Center for Wild Camel Conservation,which was jointly established earlier this year by the Institute of Remote Sensing and Digital Earth(RADI)of the Chinese     

More than Skin Deep – Understand Skin Biology by Means of Dermatogenomics

<正>The Paul Gerson Unna Research Group on Dermatogenomics was founded in October 2012 at the Partner Institute for Computational Biology.The ultimate goal of the group is to understand the biology of skin and skin appendages.