29 research outputs found

    Mobile computing with the Rover Toolkit

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    Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1998.Includes bibliographical references (leaves 138-147).by Anthony Douglas Joseph.Ph.D

    A Resource Intensive Traffic-Aware Scheme for Cluster-based Energy Conservation in Wireless Devices

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    Wireless traffic that is destined for a certain device in a network, can be exploited in order to minimize the availability and delay trade-offs, and mitigate the Energy consumption. The Energy Conservation (EC) mechanism can be node-centric by considering the traversed nodal traffic in order to prolong the network lifetime. This work describes a quantitative traffic-based approach where a clustered Sleep-Proxy mechanism takes place in order to enable each node to sleep according to the time duration of the active traffic that each node expects and experiences. Sleep-proxies within the clusters are created according to pairwise active-time comparison, where each node expects during the active periods, a requested traffic. For resource availability and recovery purposes, the caching mechanism takes place in case where the node for which the traffic is destined is not available. The proposed scheme uses Role-based nodes which are assigned to manipulate the traffic in a cluster, through the time-oriented backward difference traffic evaluation scheme. Simulation study is carried out for the proposed backward estimation scheme and the effectiveness of the end-to-end EC mechanism taking into account a number of metrics and measures for the effects while incrementing the sleep time duration under the proposed framework. Comparative simulation results show that the proposed scheme could be applied to infrastructure-less systems, providing energy-efficient resource exchange with significant minimization in the power consumption of each device.Comment: 6 pages, 8 figures, To appear in the proceedings of IEEE 14th International Conference on High Performance Computing and Communications (HPCC-2012) of the Third International Workshop on Wireless Networks and Multimedia (WNM-2012), 25-27 June 2012, Liverpool, U

    Mobile Ticketing Framework for Malaysia’s Cinemas

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    From simple and manual life into electronic services finally into mobile electronic services, the solutions of mobility services made it easier to obtain many things at anytime and anywhere, with this new services and technologies the time has come to open an another marketing channel to express product and services to the consumers. Where in strong economic structure and the successful commercial marketing, the electronic commerce Including (electronic ticketing, mobile commerce and mobile ticketing) is changing the style of company's marketing, production, and operation, in addition it facilitated the life, reduced the cost and increased the profits.In context of mobility is a crucial part of the work, this research addresses to design and development a reservation system prototype based mobile e-ticketing for Malaysia's cinemas with kedah's scope. This prototype contains two parts, web and WAP application service, web application to make ability to manage cinemas and the WAP application to give the user the possibility of booking by using mobile phone

    Locating objects in wide-area systems

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    Mobile Databases: a Selection of Open Issues and Research Directions

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    International audienceThis paper reports on the main results of a specific action on mobile databases conducted by CNRS in France from October 2001 to December 2002. The objective of this action was to review the state of progress in mobile databases and identify major research directions for the French database community. Rather than provide a survey of all important issues in mobile databases, this paper gives an outline of the directions in which the action participants are now engaged, namely: copy synchronization in disconnected computing, mobile transactions, database embedded in ultra-light devices, data confidentiality, P2P dissemination models and middleware adaptability

    System modeling and performance evaluation of rate allocation schemes for packet data services in wideband CDMA systems

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    To fully exploit the potential of a wideband CDMA-based mobile Internet computing system, an efficient algorithm is needed for judiciously performing rate allocation, so as to orchestrate and allocate bandwidth for voice services and high data rate applications. However, in existing standards (e.g., cdma2000), only a first-come-first-served equal sharing allocation algorithm is used, potentially leading to a low bandwidth utilization and inadequate support of high data rate multimedia mobile applications (e.g., video/audio files swapping, multimedia messaging services, etc.). In this paper, we first analytically model the rate allocation problem that captures realistic system constraints such as downlink power limits and control, uplink Interference effects, physical channel adaptation, and soft handoff. We then suggest six efficient rate allocation schemes that are designed based on different philosophies: rate optimal, fairness-based, and user-oriented. Simulations are performed to evaluate the effectiveness of the rate allocation schemes using realistic system parameters In our model.published_or_final_versio

    DataStations: ubiquitous transient storage for mobile users

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    technical reportIn this paper, we describe DataStations, an architecture that provides ubiquitous transient storage to arbitrary mobile applications. Mobile users can utilize a nearby DataStation as a proxy cache for their remote home file servers, as a file server to meet transient storage needs, and as a platform to share data and collaborate with other users over the wide area. A user can roam among DataStations, creating, updating and sharing files via a native file interface using a uniform file name space throughout. Our architecture provides transparent migration of file ownership and responsibility among DataStations and a user?s home file server. This design not only ensures file permanence, but also allows DataStations to reclaim their resources autonomously, allowing the system to incrementally scale to a large number of DataStations and users. The unique aspects of our DataStation design are its decentralized but uniform name space, its locality-aware peer replication mechanism, and its highly flexible consistency framework that lets users select the appropriate consistency mechanism on a per-file replica basis. Our evaluation demonstrates that DataStations can support low-latency access to remote files as well as ad-hoc data sharing and collaboration by mobile users, without compromising consistency or data safety

    Mobile Applications for Government: A Framework for Evaluating Their Economic Impact

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    An implementation strategy for a mobile app must be adjusted as the app progresses through different stages of maturity as it progresses through different stages of development as it progresses through different stages of maturity. A challenge that can arise when it comes to assessing the quality of mobile apps that are used by governments is the assessment of their quality. The reason for this is that they are progressing from the infancy stage of their use to the maturity stage of it. Through the use of a multi-item scale, this study intends to assess the quality of mobile apps offered by the governments that involve transactions in order to determine whether or not these apps are of a high quality. The results of a comprehensive review of scientific research that has been carried out by academic scholars and practitioners has led to the identification of a number of factors that influence the quality of mobile apps developed by government agencies based on a comprehensive review of scientific research. It was the purpose of our study to conduct a survey of fully functional mobile apps in order to develop a questionnaire that would be used to gather feedback from users based on an analysis of reviews and interviews with users in order to develop a survey of fully functional mobile apps. Following the quantitative analysis of the data, an appropriate scale was able to be developed based on the responses that had been received as a result of the quantitative analysis of the data. By evaluating the perceived value of government mobile applications, citizens can be able to evaluate the perceived quality of government mobile applications and the perceived value of government services. It has been found that, based on the analysis of the data, seven constructs can be used as a way of evaluating the quality of government apps on the basis of demand. A number of constructs are included in these constructs, such as user friendliness, transaction transparency, loading speeds, flexibility, complete information, trust and safety, as well as efficiency of the apps

    MobiPADS: a reflective middleware for context-aware mobile computing

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    distributed computing services that essentially abstract the underlying network services to a monolithic “black box. ” In a mobile operating environment, the fundamental assumption of middleware abstracting a unified distributed service for all types of applications operating over a static network infrastructure is no longer valid. In particular, mobile applications are not able to leverage the benefits of adaptive computing to optimize its computation based on current contextual situations. In this paper, we introduce the Mobile Platform for Actively Deployable Service (MobiPADS) system. MobiPADS is designed to support context-aware processing by providing an executing platform to enable active service deployment and reconfiguration of the service composition in response to environments of varying contexts. Unlike most mobile middleware, MobiPADS supports dynamic adaptation at both the middleware and application layers to provide flexible configuration of resources to optimize the operations of mobile applications. Within the MobiPADS system, services (known as mobilets) are configured as chained service objects to provide augmented services to the underlying mobile applications so as to alleviate the adverse conditions of a wireless environment. Index Terms—Middleware, mobile applications, mobile computing support services, mobile environments.
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