J2MEMicroDB: a new Open Source lightweight database engine for J2ME mobile devices

J2ME is the development platform for mobile devices with larger support and availability in the market right now. Due to the minimalist definition of this architecture it does include neither API’s for data persistence management, like object serialization, and relational database access nor standard APIs to access a remote host. This paper presents J2MEMicroDB, an Open Source software that implements object serialization, a local relational database engine on the mobile device and a remote database access protocol that allows access to any JDBC database. In the design and implementation of J2MEMicroDB specific requirements and limitation of mobile devices have been considered. Even some performance improvements have been developed, like BTree indexing structures which improves significantly the efficiency of the searches, as the presented cross-platform benchmarking proves.     

Controlling energy without compromising system performance in mobile grid environments

The challenges confronting in mobile grid systems are: limited CPU power, limited memory, small screen, short battery life, and intermittent disconnection. Considering all these limitations, this paper is targeted to control energy consumption without compromising system’s performance in mobile grid. In this paper, we focus on using the mobile devices on the mobile grid environment. Mobile devices can serve two important functions in mobile grid environment either as service consumer or as valuable service providers. The proposed approach is not only to reduce energy consumption, but also to improve system performance in mobile grid environment. Utility functions are used to express grid users’ requirements, resource providers’ benefit function and system’s objectives. Dynamic programming is used to optimize the total utility function of mobile grid. A distributed controlling energy algorithm in mobile grid environment is proposed which decomposes mobile grid system optimization problem into sub-problems. In order to verify the efficiency of the proposed algorithm, in the experiment, the performance evaluation of controlling energy algorithm is conducted.     

Deploying personalized mobile services in an agent-based environment

The mobile Internet allows users to obtain digitized contents and services from wired and wireless networks virtually anywhere at any time via different handheld mobile devices. However, due to the distinct features of mobile users, mobile devices and wireless networks, deploying mobile services is not as straightforward as generally expected. To ensure the success of mobile services, this paper presents a multi-agent framework that considers different contexts to support personalized services on wireless networks. In the proposed approach, client users, content providers, and service providers are all considered as software agents. They interoperate on the same platform to request and deliver mobile services. The most important issues related to agent operations and context awareness in an agent world are also discussed and analyzed. To verify our framework, different application services are developed accordingly on a publicly available middleware platform. Experiments are conducted for both services to evaluate their corresponding performance. The preliminary results show that our multi-agent approach to personalization is promising and efficient in the deployment of mobile services.     

A Web-based, Offline-able, and Personalized Runtime Environment for executing applications on mobile devices

An increasing number of people use cell phones daily. Users are not only capable of making phone calls, but can also install applications on their mobile phones. When creating mobile applications, developers usually encounter the cross-platform incompatibility problem (for example, iPhone applications cannot be executed on the Android platform). Moreover, because mobile Web browsers have increasingly supported more and more Web-related standards, Web applications are more possible to be executed on different platforms than mobile applications. However, the problem of Web application is that it cannot be executed in offline mode. This study proposes a Web-based platform for executing applications on mobile devices. This platform provides several services for developers such as offline service, content adaptation service, and synchronization service. With the help of the proposed platform, application developers can develop and publish offline Web applications easily with simplified external Web content and synchronization capability.     

A study on stackable mosaic generation for mobile devices

With the growing use of mobile devices such as smartphones, tablet PCs, and digital cameras, photography has become an integral part of everyday life. In particular, mobile devices with cameras allow us to easily capture and modify photographs that can be shared via social networks. In this paper, we introduce a mobile device application for converting photographs into photomosaic images. In general, high-quality photomosaics require large databases. However, mobile devices have limited resources; hence it is difficult for such devices to support photomosaics. We propose a method that produces a photomosaic effect using a database that consists of rotatable images. We also propose a solution to the performance issue based on a best match search.     

Neck kinematics and muscle activity during mobile device operations

Neck pain is a significant health problem due to its high incident rates and economic costs. Increased use of touch screen mobile devices is becoming pervasive in the modern society and may further influence this already prevalent health problem. However, our current understanding of the cervical spine biomechanics during the operation of touch screen mobile devices is very limited. This study evaluated the neck extensor muscle activities and the kinematics of the cervical spine during the operation of a touch screen tablet and a smart phone. Three-variables, DEVICE, LOCATION and TASK were treated as the independent variables. NASA TLX revealed that “Gaming” was the least difficult task and “Typing” was the most difficult task. Participants of this study maintained significantly deeper neck flexion when operating a smart phone (44.7°), with the mobile devices set on a table (46.4°), and while performing a “Typing” task (45.6°). Lower levels of neck muscle activities were observed while performing a “Reading” task and holding mobile devices with hand. Lower levels of neck muscle activities were also observed when using a smart phone vs. a tablet, however such change was statistically insignificant.Relevance to industryThe current study demonstrated that users maintain deep neck flexion when using touchscreen mobile devices. In the recent years, there is an increasing popularity of mobile smart devices in various occupational environments. The findings of this study may be useful in implementing human-centered task designs to reduce neck injury risks among mobile device users.     

A personal mobile DRM manager for smartphones

In this paper we report on our experience in building the experimental Personal Digital Rights Manager for Motorola smartphones, an industry first.Digital Rights Management allows producers or owners of digital content to control the manner in which the content is consumed. This may range from simply preventing duplication to finer access policies such as restricting who can use the content, on what devices, and for how long. In most commercial DRM systems, the average end user plays the role of content consumer, using DRM protected content made available by a service. Here we present a personal digital rights system for mobile devices where the end user has the ability to place DRM protection and controls on his or her own personal content.We designed the personal DRM system to allow users of a mobile device to transparently define controls and generate licenses on custom content and securely transfer them to other mobile devices. A user is able to define and restrict the intended audience and ensure expiration of the content as desired. Compatible devices automatically detect each other and exchange credentials. The personal DRM system on each device safely enforces the content usage rules and also handles moving licenses between devices while preventing leakage of content. We implemented a prototype of our system on Motorola E680i smartphones.     

Wukong: A cloud-oriented file service for mobile Internet devices

Along with the rapid growth of heterogeneous cloud services and network technologies, an increasing number of mobile devices use cloud storage services to enlarge their capacity and share data in our daily lives. We commonly use cloud service client-side software in a straightforward fashion. However, when more devices and users participate in heterogeneous services, the difficulty of managing these services efficiently and conveniently increases. In this paper, we report a novel cloud-oriented file service, Wukong, which provides a user-friendly and highly available facilitative data access method for mobile devices in cloud settings. Wukong supports mobile applications, which may access local files only, transparently accessing cloud services with a relatively high performance. To the best of our knowledge, Wukong is the first file service that supports heterogeneous cloud services for mobile devices by using the innovative storage abstraction layer. We have implemented a prototype with several plugins and evaluated it in a systematic way. We find that this easily operable file service has a high usability and extensibility. It costs about 50 to 150 lines of code to implement a new backend service support plugin. Wukong achieves an acceptable throughput of 179.11 kB/s in an ADSL environment and 80.68 kB/s under a countryside EVDO 3G network with negligible overhead.     

Adaptive searching and replication of images in mobile hierarchical peer-to-peer networks

Due to the limitation of resources in mobile handheld devices and bandwidth constraints in wireless networks, it is important to efficiently manage image content and traffic to improve network throughput and response time. The efficient distribution of images in wireless networks is based on many parameters like the quality of service requirement, available bandwidth, restricted memory and diverse user profiles. We consider digital images as data objects accessed in a hierarchical mobile ad-hoc peer-to-peer network, referred as M-P2P. Our objective is to optimize the number of replicas of images in such a network architecture based on the resource limitations of the requesting peers equipped with miniature mobile devices as well as of wireless constraints in mobile ad-hoc networks (MANET). While replicating images, fragments of different resolution and their residues are used to optimize the traffic in the network and to decrease the search turnaround time. We call this replication algorithm as Ada-Rep. Performance evaluation is done by simulating Ada-Rep, base replication and uniform replication methods to evaluate parameters such as response time, failure rate, memory usage, traffic etc. Our results prove the efficiency and better performance of Ada-Rep.     

针对移动云计算任务迁移的快速高效调度算法

计算量较大的应用程序由于需要大量的能耗,因此在电池容量有限的移动设备上运行时十分受限。云计算迁移技术是保证此类应用程序在资源有限的设备上运行的主流方法。针对无线网络中应用程序任务图的调度和迁移问题,提出了一种快速高效的启发式算法。该算法将能够迁移到云端的任务都安排在云端完成这种策略作为初始解,通过逐次计算可迁移任务在移动端运行的能耗节省量,依次将节省量最大的任务迁移到移动端,并依据任务间的通讯时间及时更新各个任务的能耗节省量。为了寻找全局最优解,构造了适用于此问题的禁忌搜索算法,给出了相应的编码方法、禁忌表、邻域解以及算法终止准则。构造的禁忌搜索算法以提出的启发式解为初始解进行全局搜索,并实现对启发解的进一步优化。通过 实验 将所提方法与无迁移、随机迁移、饱和迁移3类算法进行对比,结果表明提出的启发式算法能够快速有效地给出能耗更小的解。例如,在宽度为10的任务图上,当深度为8时,无迁移、随机迁移与饱和迁移的能耗分别为5461、3357和2271能量单位,而给出的启发解对应的能耗仅为2111。在此基础上禁忌搜索算法又将其能耗降低到1942, 这进一步说明了提出的启发式算法能够产生高质量的近似解。     

Context-driven encrypted multimedia traffic classification on mobile devices

The Internet has been experiencing immense growth in multimedia traffic from mobile devices. The increase in traffic presents many challenges to user-centric networks, network operators, and service providers. Foremost among these challenges is the inability of networks to determine the types of encrypted traffic and thus the level of network service the traffic needs to maintain an acceptable quality of experience. Therefore, end devices are a natural fit for performing traffic classification since end devices have more contextual information about device usage and traffic. This paper proposes a novel approach that classifies multimedia traffic types produced and consumed on mobile devices. The technique relies on a mobile device’s detection of its multimedia context characterized by its utilization of different media input/output (I/O) components, e.g., camera, microphone, and speaker. We develop an algorithm, MediaSense, which senses the states of multiple I/O components and identifies the specific multimedia context of a mobile device in real-time. We demonstrate that MediaSense classifies encrypted multimedia traffic in real-time as accurately as deep learning approaches and with even better generalizability.     

一种基于图复杂度的移动导航服务回归测试优先方法

随着现代移动导航服务的实时化、智能化发展,导航服务算法日益复杂,影响其服务质量的因素众多,使得移动导航服务测试验证较为困难。文中提出一种基于图复杂度的移动导航服务回归测试优先方法,该方法通过设定导航服务区域,基于图复杂度理论,提出可达交叉点数、交叉点的交叉度、可达路段数、最短可达路线的路段数等5个优先指标,用于对回归测试数据优先排序,以提高移动导航服务的回归测试效率。     

CAD data visualization on mobile devices using sequential constrained Delaunay triangulation

3D graphic rendering in mobile application programs is becoming increasingly popular with rapid advances in mobile device technology. Current 3D graphic rendering engines for mobile devices do not provide triangulation capabilities for surfaces; therefore, mobile 3D graphic applications have been dealing only with pre-tessellated geometric data. Since triangulation is comparatively expensive in terms of computation, real-time tessellation cannot be easily implemented on mobile devices with limited resources. No research has yet been reported on real-time triangulation on mobile devices.In this paper, we propose a real-time triangulation algorithm for visualization on mobile devices based on sequential constrained Delaunay triangulation. We apply a compact data structure and a sequential triangulation process for visualization of CAD data on mobile devices. In order to achieve a high performance and compact implementation of the triangulation, the nature of the CAD data is fully considered in the computational process. This paper also presents a prototype implementation for a mobile 3D CAD viewer running on a handheld Personal Digital Assistant (PDA).     

基于移动Agent技术的Internet模糊信息服务模型

提出一种基于移动Agent技术的Internet模糊信息服务模型,讨论了其总体工作框架和结构。将模糊检索算法用于Internet信息的智能搜索,给出了信息检索系统的设计方法。用Java语言实现该模型的软件平台,通过实验验证了其可行性。     

Utilizing national public-key infrastructure in mobile payment systems

Payments are the locomotive behind any business domain. It has been predicted that mobile payments will become one of the most successful mobile services, and the security of payments is an important requirement. However, it is difficult to strongly authenticate mobile users remotely and provide an adequate level of non-repudiation of transactions. In this article, we argue that a nationwide public-key infrastructure supported by governmental bodies can be used in a mobile payment system. Not only does it provide strong security, but it also makes the system open to any mobile user, merchant, or financial service provider. Two payment protocols are described: one for virtual point-of-sale payments, and one for vending machine payments. We argue that such a system can be implemented using open development platforms, and its performance is adequate for enabling swift transactions. A prototype of a system which accepts virtual point-of-sale payments is implemented, and its performance and usability are evaluated.     

Mobile local search with noisy locations

The deep penetration of mobile devices have led to the emergence of multiple mobile applications that seek to harness the positioning capabilities embedded in such devices. One of the most functional of these applications is local search. Local search is similar to a regular web search, yet is more powerful in a mobile setting since results are ranked both by prominence and locality. Undoubtedly popular, the current design of local search applications fails to cater equally to a privacy-aware user who desires finer controls in her location disclosure. Towards this end, we propose the design for a private local search (PriLS) application that enables a user to first learn the geographic variation in local search results and then use it to determine a noisy location that has little or no affect on the search results. Parametric studies and real-world evaluations show that PriLS can help identify geographic locations that would produce similar search results (compared to when the user’s location is used) with no noticeable delays in user experience. They also reveal that large areas typically exist where there is no change in the result of a local search query, and can be exploited to provide spatial privacy guarantees to a user.     

基于 Phonegap 的移动课件应用的设计与实现

随着移动互联网的快速发展,在移动设备上观看讲座、培训课件等视频将成为空闲时间学习的重要途径,而课件视频容量太大,下载耗时太长无疑造成了课件资源获取、存储上的困难,给移动学习带来了很多不便.本文提出了只使用课件音频、课件 ppt 图片以及图片时间配置文件来取代视频播放的解决方案,并详细介绍了基于 Phonegap 的移动混合方式开发的原理与好处以及应用系统的关键模块的详细设计与实现.     

物联网中多设备多服务器的移动边缘计算任务卸载技术综述

随着物联网(Internet of Things,IoT)技术的快速发展,出现了大量具有不同功能的设备(如多种带不同传感器的智能家居设备、移动智能交通设备、智能物流或仓储管理设备等),它们相互连接,被广泛应用于智能城市、智慧工厂等领域.然而,这些物联网设备的处理能力有限,很难满足延迟敏感、计算密集型应用的需求.移动边缘...     

基于语义Web技术的上下文感知的智能移动服务

语义Web技术应用于上下文感知的智能移动服务，通过构建上下文信息本体，使得移动服务的实体之间可以进行上下文信息共享和语义互操作，并进行上下文信息推理，实现智能服务。本文首先介绍了语义Web及本体技术，其次阐述了语义Web技术应用于上下文感知的移动服务，然后详细分析了智能移动服务中的上下文信息本体构建，包括通用的上下文信息本体、用户概况本体、情境本体以及服务本体等，接着介绍了相关的研究项目，最后进行展望和总结。