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61.
随着通信市场迅速发展和手机的高普及率,利用手机数据研究人类活动和城市规划发展成为可能.本文主要工作是构建了大数据实时处理分析平台,并基于此平台提出了一种利用手机数据感知城市人口分布的方法.通过实验表明,基于手机数据的动态人口感知能够反映实际城市人口分布,对于城市交通监管、公共资源配置优化等方面具有重要意义.  相似文献   
62.
Tourist recommendation services provide suggestions for places of interest. While the spatial structure of a tourist's visit has been successfully exploited to improve the quality of place recommendations, its temporal structure has not been taken into account so far. This is surprising because the importance of the visitors' time management is well known from tourism research. We present findings of an empirical study that sheds light on the temporal aspects of tourist exploration behaviour and discuss implications for the design of tourist-recommender systems. The data-set consists of interviews, GPS tracks and geo-referenced photo sequences from visitors of a typical Middle European destination for cultural tourism. Among the results relevant to place recommending are the following: (1) the set of places is often replanned during the visit; (2) comparing place popularity based on photo frequency and place popularity based on staying time, we found notable differences in rank ordering; and (3) the photo frequency and the detour sinuosity of the GPS tracks are decreasing slowly over time. We interpret this last finding as a time-geographic cone effect. Based on the empirical results, we discuss the implications for the design of tourist-recommending services and propose a corresponding user interface utilising a recommendation strategy that tries to counterbalance the time-geographic cone effect, that is, to decelerate the visiting experience.  相似文献   
63.
Abstract

This article reports on the current state of reference services on the World Wide Web (WWW). It explains what a WWW-based reference service is, describes several models of handling requests, and explores the impact of these services on traditional reference services. Based upon anecdotal information the author concludes that, to date, Web-based reference services have had little impact upon traditional reference services.  相似文献   
64.
Virtual reference service has become ubiquitous in academic libraries. The increased adoption of chat technology brings to light some of the challenges of providing high-quality reference service. The lack of a personal connection, increased transaction time, and technical problems are often cited. Techniques, such as conducting a reference interview or using online communication conventions, can make virtual reference as effective as face-to-face reference. Additionally, inclusion of video or Web annotation in the virtual reference session can add an element of personalization that might otherwise be missing. Virtual reference can be an emotionally rich, engaging, and effective form of reference service if these techniques and technologies are adopted.  相似文献   
65.
SUMMARY

As distance education courses increasingly move to the online environment, librarians are discovering new challenges and opportunities for reaching distant students. Collaboration with faculty is essential in reaching students who may never enter the library building. One such method of collaboration is librarian participation in online courses through “lurking” in Blackboard and Desire2Learn classrooms and monitoring discussion threads devoted to library research. Advantages such as improved access to students, course content, and assessment data are discussed, as are disadvantages, such as time commitment, varying expectations, and privacy issues. Considerations for librarians interested in “lurking” are outlined.  相似文献   
66.
Frameworks for aggregating similar services into structures called communities have been recently advocated. A common assumption in those frameworks is that residing services are coopetitive, i.e., competing over received requests, but also cooperating, for instance in terms of substituting each other. In this coopetition context, deciding to compete or cooperate at different moments in time is an open question yet to be addressed. The contribution of this paper is the answer to this challenging question by proposing a game-theoretic-based decision mechanism that services can use to effectively choose competition or cooperation strategies that maximize their payoffs. To achieve this objective, we investigate autonomous services’ characteristics and their expected utilities over different strategies. We propose a game-theoretic best response technique to measure the threshold that services can use in order to decide about the two strategies. We prove that the proposed decision mechanism is efficient and can be implemented in time linear in the length of the time period considered for the analysis and the number of services in the community. Moreover, we conduct extensive simulations to analyze various scenarios and confirm the obtained theoretical results. Those results show that our model outperforms existing competitive and random coopetitive strategies and the more services deviate from our game-theoretic-based coopetitive strategy the more they make less benefits.  相似文献   
67.
The objective of this study was to assess the response to location-based services (LBS) by three key demographic groups within the United Kingdom. This study took the form of a survey of relevant demographics, attitudes and consumer behaviour undertaken via a web-based survey. Results are based on over 1200 respondents, filtered and segmented into three demographic groups who are typically early adopters of new technology. There were positive attitudes towards a range of LBS, with the major exception being location-based advertising. There were mixed views towards location-based gaming and safety camera information. There were low levels of awareness of many services. The levels of use were typically under 20% for all types of LBS.  相似文献   
68.
Machine tools (MTs), as the key equipment of manufacturing systems, have enormous quantities and consume a great amount of energy. However, the diversity of both machines and their energy consumption properties make it difficult to transfer the energy-saving knowledge and services among different MT. To facilitate the initialization configuration of energy-saving services, the inherent energy performance (IEP) is investigated to describe the differences in energy consumption among MTs, and a generalized method for modeling the IEP of MT and its electrical subsystems is proposed. Three key enablers, including generalized experimental design rules, automatic coding, and data processing algorithms, are presented and integrated into a supporting system to reduce the modeling efforts and knowledge requirements. Case studies of an offline manufacturing scenario and an Internet of Things (IoT)-enabled manufacturing scenario were carried out to verify the effectiveness and convenience of the proposed method. The results show that the proposed method can provide essential modeling support for large-scale energy-saving service configurations and energy-efficient MT development.  相似文献   
69.
A key agenda of policy-makers in both the developing and the developed worlds is to have an inclusive growth. Financial services have been recognised as one of the fundamental services that have the potential to achieve this objective and help move towards a more just and equitable society. This paper attempts to assess the impact of three information and communication technology-driven initiatives in the field of financial services by differentiating them on the basis of service design. This study goes beyond the stated objective of these services and uses Sen’s capability perspective to study their impact across three non-economic outcome variables viz. literacy, service-specific well-being and empowerment. The data for the study are collected from the urban poor across different locations in a large metropolitan city in South India where the three different services are being offered. The study follows a quasi-experimental design (field study) and ensures matching of the treatment and control groups through propensity score matching. The matched data are analysed using an independent sample t-test. The result of the analysis shows that service design plays a key role in increasing service literacy, improving service-specific well-being and empowering end users. The study suggests that the true challenge for providers (government and partner agencies) of these services is in designing a service that ensures a balance of structure and flexibility without constraining the choice of end users through innovative service blueprints.  相似文献   
70.
Rubber agroforests in the mostly deforested lowlands of Sumatra, Indonesia are threatened by conversion into monoculture rubber or oil palm plantations. We applied an agent-based model to explore the potential effectiveness of a payment for ecosystem services (PES) design through a biodiversity rich rubber eco-certification scheme. We integrated conditionality, where compliance with biodiversity performance indicators is prerequisite for awarding incentives. We compared a PES policy scenario to ‘business-as-usual’ and ‘subsidized land use change’ scenarios to explore potential trade-offs between ecosystem services delivery and rural income. Results indicated that a rubber agroforest eco-certification scheme could reduce carbon emissions and species loss better than alternative scenarios. However, the suggested premiums were too low to compete with income from other land uses. Nevertheless, integrating our understanding of household agent behavior through a spatially explicit and agent-specific assessment of the trade-offs can help refine the design of conservation initiatives such as PES.  相似文献   
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