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The last thirty years have seen tremendous growth in research in mobile telecommunications. However, interest in mobile computing, which includes mobile telephony and more, has increased over the last ten years. Nevertheless, most of the research on mobile computing addresses the "engineering" issues and the electronic componentary required for building mobile systems. On the other hand, algorithmics research in mobile computing is still in its infancy, and only dates back to few years. The elegance and terseness that exist today in algorithmics, especially parallel computing algorirthmics, can be brought to bear on research on "mobile computing algorithmics". However, mobility brings to the stage a whole gamut of new problems that needs to be addressed in order to develop new and efficient parallel algorithms that can be used to solve mobile computing problems.

Electronic activities are realized on the Internet due to the growth of the Internet. As conference organization is getting more popular, we proposed an electronic virtual conference system (EVCS) to handle all activities of real-world conferences. The EVCS includes a virtual conference management system (VCMS) and a mobile conferencing system (MCS). Video conferencing is a trend of future communications. With the improvement of broadband network technologies, video conferencing becomes possible in the global society. It is feasible to use video conferencing technologies to organize future international conferences. As such, transportation and accommodation costs are saved. This paper proposed a total solution toward virtual conferencing. We use a mobile server/storage pre-broadcasting technique, as well as a communication network optimization algorithm, which is based on a graph computation mechanism. The system also relies on a network bandwidth reservation facility as well as a multicasting control function. With the assistance of the virtual conference management system, the system is able to support virtual conferencing in the future academic society.

For mobile computing system such as wearable computer, one of the most critical hardware issues is the provision of electric power. Various different sources of power for wearable computer have been investigated; however, we are interested only in power that can be generated in-situ, such as human power. This paper describes a novel mean of multiple source human power generation for small wearable electronic devices, and then demonstrates the digital information transfer between wearable computing devices by using human skin as "antenna".

There are a wide range of peripheral devices in a mobile computing system, such as sensors and identification memory tags. As the amount of such devices increases in a mobile computing design, there is a need for these devices to communicate efficiently with the central processing unit. Also, it is highly desirable that these devices could be conveniently connected to the wearable computer without many dangling wires. We developed a personal area network (PAN) system which attempts to interconnect such devices, and at the same time uses human body as communication channel. This system is in a way novel because it is totally powered by human motion.

The number and variety of applications for mobile devices continue to grow. However, the resources on mobile devices including computation and storage do not keep pace with the growth. How to incorporate the computation capacity on cloud servers into mobile computing has been desired and challenge issues to resolve. In this work, we design an elastic computation framework to take advantage the heterogeneous computation capacity on cloud servers, which consist of CPUs and GPGPUs, to meet the computation demands of ever growing mobile applications. The computation framework extends OpenCL framework to link remote processors with local mobile applications. The framework is flexible in the sense that the computation can be stopped at any time and gains results, which is called imprecise computation in real-time computing literature. The framework has been evaluated against OpenCL benchmark and physical computation engine for gaming. The results show that the framework supports OpenCL benchmark, RODINIA, without modifying the codes with few exceptions. The elastic computation framework allows the cloud servers to support more mobile clients without sacrificing their QoS requirements. The experiment results also show that IO intensive applications do not perform well when the network capacity is insufficient or unreliable.

Recently available low-cost personal computers and mechanisms to produce digital data have caused a staggering increase in the amount of multimedia data acquired by the user. Hence, the user's personal information space that consists of a large collection of files, may distribute over a number of computers. Situation-dependent metaphor methodology, described in this paper, provides a novel approach to managing such a collection with respect to the context of user's interactions with data. By considering the mobile computing environment, the physical location, time periods and activities are primarily used in modeling the situation metaphor. Sensors and software agents are used in capturing contextual factors automatically. Situation Space describes the theoretical foundation for the situation metaphor based information organization. We also presents our prototype engineered model, Situated Information Filing and Filtering (SIFF), to demonstrate the situation-dependent data management. The SIFF provides the framework for organizing the personal information and developing applications that require contextual information.

Two significant performance factors in Mobile Agent Planning (MAP) for distributed information retrieval are the number of mobile agents and the total execution time. Using fewer mobile agents results in less network traffic and consumes less bandwidth. Regardless of the number of agents used, the total execution time for a task must be kept to a minimum. A retrieval service must minimize both these factors for better system performance, and at the same time, it must be able to supply the required information to users as quickly as possible. In this paper, we propose heuristic algorithms, called Cost-Effective MAP (CEMAP), to minimize both the number of mobile agents and the total execution time under the condition that the turnaround time is kept to a minimum. Although these algorithms tend to slightly increase the planning cost, a simulation study shows that these algorithms enhance the system performance significantly. By adopting these algorithms, systems can maintain lower network traffic while satisfying the minimum turnaround time.

The decoupled nature of computing in mobile ad hoc networks (MANETs) can result in disconnections at inopportune times during an interaction between a pair of hosts. We introduce the notion of a priori selection of partner hosts to reduce the likelihood of disconnection during such interactions. An application may specify the times when and the physical locations where it requires interactions with peer applications on partner hosts. A knowledge base of the physical motion profiles of various hosts maintained on each mobile host is used to select partner hosts that are co-located with the reference host at the required time and are least likely to disconnect. In this paper, we present a formal model for such knowledge management, along with an algorithm used to determine suitable partner hosts. We also provide details of our implementation of partner selection, which has been used in the context of a service-oriented computing middleware for MANETs, developed previously by our group. Finally, we present simulation results of our approach.

The collection of outcomes data is critical for conducting clinical studies in orthopaedic surgery. Both subjective outcome data [e.g. Short Form-12 (SF-12) and Western Ontario Rotator Cuff (WORC) index] and objective data (e.g. range of motion) are necessary. Numerous studies have been conducted on the collection of patient survey data through electronic means (e.g. personal digital assistant and tablet PC), but none of these studies have made use of a device with an intuitive touch-screen interface. Studies have also been conducted on the collection of physical examination data through research-grade accelerometers but few have focused on the use of commercially available electronic devices. The goal of our project was to develop a mobile computing touch-screen system for capturing subjective and objective outcome data for the assessment of patients with rotator cuff tears. We were able to accomplish this goal through the development of a novel iPad/iPod Touch tool. Intra-rater and inter-rater reliability of shoulder flexion and external rotation measurements were good.

Future mobile multimedia systems will have wearable computing devices as their front ends, supported by database servers, I/O servers, and compute servers over a backbone network. Multimedia applications on such systems are demanding in terms of network and compute resources, and have stringent Quality of Service (QoS) requirements. Providing QoS has two aspects. On the one hand, the QoS requirements for the relevant resources have to be defined and suitable policies for meeting these requirements have to be devised and analyzed. On the other hand, the architecture of the system components and the mechanisms enabling the implementation of these policies have to be designed. In this paper we propose an architecture called HARMONY for providing QoS in mobile computing environments. The HARMONY architecture is a layered architecture that provides mechanisms for the management of network and compute resources, in particular for call admission control taking into account the simultaneous requests for both types of resources by the mobile units. It also provides a mechanism for mobility management of mobile units as they move from one cell to another in a mobile computing environment. The network resources are reserved based on the Entropy model. In order to provide compute guarantees, we provide a novel scheme for off-loading tasks from the mobile units to the compute servers in the backbone network. We propose a load-balancing scheme to minimize the call blocking probability due to lack of compute resources, which redistributes the total load in the system across all compute servers so that these are equally loaded. Through a quantitative analysis of the HARMONY architecture we establish its effectiveness in providing quality of service in mobile computing environments.

A dual channel system, which is based on the GPS and the GSM Network, is being developed to compensate the problem of the lost of GPS signals in providing location services to mobile users in urban areas. In this design, when GPS signals are being blocked in blind spot areas, GSM positioning algorithms would be used as an alternative method to provide location estimations. This research is an investigation in search of a set of location estimation algorithms based on signal attenuation to work with GPS, so as to develop a dual channel positioning system. With the technical support from a local mobile operator, we have constructed and conducted several real world experiments for our investigation and results are promising.

Data dissemination scheme has been of great interest due to its scalability. In mobile environment, the advantage of such scheme is significant considering the inherent limitations of wireless environment. The application of broadcast indexing scheme in a wireless broadcast environment is necessary to help mobile clients to find the desired data instances efficiently. In this paper, we present a novel index structure called global indexing scheme for location-dependent queries. The proposed scheme is applied in a multi channel wireless environment and designed to serve queries efficiently in which the queries result depend on the mobile clients' current location. We develop a simulation model to find out the access time, tuning time and power consumption performance of global indexing scheme as compared to non-global indexing scheme. Additionally, we analyse the efficiency of valid scope used in the global index scheme as compared with an existing valid scope. It is found that global index performs substantially better than the existing indexing concept.

This paper proposes a semi-automatic method of geographic information linking based on spatial relationships, entity names, entity categories and other features, combined with semantic and machine learning methods. First, we extracted geographic information from three geographic information sources: Open Street Map, Wikimapia, and Google places. The extracted geographic information is mainly for urban buildings in different regions. Secondly, we analyzed and extracted the characteristics of geographic information data to construct a geographic information ontology, and realized the integration of geographic data through the mapping of geographic information source data and geographic information ontology. Finally, the linking method of fusion classification algorithm support vector machine and K-nearest neighbor method are discussed separately. At the same time, it is compared with the linking method proposed by Samal et al. to comprehensively verify the accuracy of the method proposed in this paper from multiple angles, laying a good foundation for seismic information integration.

The work described in this paper proposes and evaluates an end-to-end communication approach in realizing terminal mobility in IP wireless access networks. The proposed network architecture also provides a solution to multi-homing in IPv4 and IPv6 networks. It concentrates on end-to-end abstraction and does not require any special service from the underlay network infrastructure. The multi-homing capability is used to achieve seamless handoff. Based on multi-homing we also propose and evaluate a handoff scheme that exploits the overlapping coverage area and speed of the mobile node between sub-networks. We describe the network architecture and show its mobility and multi-homing capability by prototype implementation and by performance evaluation. Our implementation does not have any significant bad performance impact on plain versions of IPv4 and IPv6. The evaluation of handoff scheme shows that packet loss and handoff latency can be reduced significantly even with the end-to-end design, depending upon the characteristics of underlay wireless access network.

With advances in the Internet of Things and communication technologies, the diversity of edge devices has attracted excessive computational loads to these technology systems while causing device heterogeneity. In the context of mobile edge computing, differences in communication and computing resources of edge devices may affect the performance of the model. In personalized federated learning, the differences among different devices can further widen the convergence effect differences. Thus, we propose a multi-exit selection mechanism based on limited resource allocation, which allows devices with weaker computing power to end training early. Subsequently, we propose a hierarchical personalized federated learning algorithm called FedMEM, which is based on the multi-exit selection mechanism. The algorithm divides the local model into a global layer and a personalized layer, with the global layer participating in federated model aggregation while the personalized layer is retained locally. Simulation results show that compared with FedAvg and FedPre algorithms, the proposed algorithm achieves better results and considerably reduces transmission delay.

Compared to today’s traditional distributed systems, the mobile computing environment is very different in many respects. Limited battery life and high communication prices are bottlenecks in mobile computing, so a new method is urgently needed to resolve such problems. This paper proposed a new framework to meet the demands of future wireless applications. In the framework we propose Asynchronous Access Pattern (AAP) and Service Configure File (SCF) supporting disconnection (include voluntarily and involuntarily) operations for mobile clients. AAP allow a mobile user voluntarily disconnect itself from the server to save its battery life and avoid high communication prices. And new wireless applications are easy to be developed/deployed based on SCF in our framework.

Location-Dependent Query is becoming more and more important in mobile environments. In this paper, to improve system performance, author proposes a new model for LDQ. Firstly, a new structure of semantic index is defined, which can store semantic segment circle and timestamp information. Then we analyze the detailed query processing based on our semantic model. To overcome the shortage of FAR at location prediction and influence of semantic valid scope to cache hit ratio, we propose a new improved replacement algorithm (RBF-FAR), in which a cost function P based on semantic segment distance and valid scope, is introduced as replacement criterion. The experiment results show that new model can gain better performance at response time, network-load and cache hit ratio, than the model on the basis of FAR algorithm.

This paper focusses on adapting the lifetime value of binding update for mobile nodes in a hierarchical Mobile IPv6. In our proposal, mobile node's lifetime can be adjusted from minimum value to maximum value according to mobile nodes's mobility pattern. The simulation result presented in this paper shows that our proposal can reduce the signaling cost for binding update by dynamic allocation of binding update lifetime.

Aiming at the issue of collaboration plotting in mobile computing environment, a mobile collaboration plotting system based on multi-agent was constructed. At first, the interrelated formalizable definition about mobile collaboration plotting system was given. Then, the collaboration model of multi-agent was introduced, the architecture of mobile collaboration plotting based on multi-agent was proposed. And, the algorithm of mobile collaboration plotting was designed. At last the prototype instance of the system was shown. The practice indicates the system was feasible and efficacious and provided strong support to the implement of mobile collaboration plotting.

Aiming at the mobile user collaboration issue in mobile collaboration computing environment, a novel model, named MUGFM (mobile user group forming model), was proposed. Based on the discussion about the cooperation requirement and cooperative ways of mobile user, the spatial-temporal factors and collaboration interest of cooperative mobile user were taken as the mainly matter formed the mobile collaborative group, under the specific character of mobile computing environment. Compared with previous user model, the MUGFM is more embodying the essence characteristic of mobile users in a mobile collaboration group, because of the collaboration interest of cooperative mobile user was been considered. So, the MUGFM fit to the specific situation of mobile collaborative computing environment more than others. Nowadays, the MUGFM was applied to the platform building that support the mobile collaboration services. The result indicated that the model has the correctness semantic and the ability depicting effectively the formulation mechanism of mobile collaborative group in mobile collaboration.

Although more and more organizations are adopting mobile computing devices such as smartphones and tablets, not all companies are equally profiting from the integration of mobile information systems (IS) and information technology (IT). This is surprising since the benefits of mobile IS/IT adoption cited in literature, such as productivity and motivation increases, are rather generic and should – in theory – be measurable in every instance of mobile IS/IT adoption. We address this issue by developing a conceptual model of the benefits of mobile IS/IT adoption and a number of key moderators, which we believe may offer an explanation why some companies are failing to reap these benefits. The model is based on a deductive-inductive research approach, combining an extensive literature review and 17 interviews with mobile computing experts in major German and Swiss public corporations. The model therefore integrates insights from theory and practice to arrive at a more holistic understanding of our research topic.