• Journal of KIISE:Computing Practices and Letters
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• v.16 no.3
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• pp.263-274
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• 2010

Mutual exclusion that applied on existing systems was designed for static distributed systems. but now computing environments are going to mobile computing environments. Therefore a mutual exclusion algorithm in static distributed environments should be designed for new computing environments. So this paper proposes a mobile mutual exclusion algorithm to support the mutual exclusion of shared resources in mobile computer environments. Mobile computing resources as wireless hosts cause new issues because of their mobility and weakness and made mutual exclusion problem more complex than stationary distributed environments. So we proposed a new mobile token mutual exclusion algorithm with deadlock-free and starvation-free in mobile computing environments based on spanning tree topology and extend for mobile computing environments. The proposed algorithm minimizes message complexity in case of free hopping in cellular networks.

• Journal of Korea Society of Digital Industry and Information Management
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• v.8 no.1
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• pp.99-105
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• 2012

Given the numbers of smartphones, tablets and other mobile devices shipped every day, more and more users are relying on the cloud as the main driver for satisfying their computing needs, whether it is data storage, applications or infrastructure. Mobile cloud computing is simply cloud computing in which at least some of the devices involved are mobile. Each node is owned by a different user and is likely to be mobile. Using mobile hardware for cloud computing has advantages over using traditional hardware. These advantage include computational access to multimedia and sensor data without the need for large network transfer, more efficient access to data stored on other mobile devices and distributed ownership and maintenance of hardware. It is important to predict job execution time in mobile cloud computing because there are many mobile nodes with different capabilities. This paper analyzes the job execution time for mobile cloud computing in terms of network environment and heterogeneous mobile nodes using a mathematical model.

• Journal of Internet Computing and Services
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• v.8 no.3
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• pp.85-98
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• 2007

In distributed computing paradigm, mobile surrogate systems have not gained wide acceptance because of security concerns that have not been suitably addressed yet. Currently even the widely used Grid middleware, Globus, does not have a host authentication mechanism, which makes it hard to provide high performance Grid computing capabilities to mobile clients. In this paper, a mobile Grid service framework is designed and implemented in order to provide Grid services to mobile host such as PDA. The surrogate host-based system allows mobile hosts to be provided with Grid services while moving. The implemented mobile Grid services system has been applied to mobile healthcare system which utilizes Grid computing for ECG signal processing. The presented system framework can be used as a secure enterprise mobile healthcare system for hospital physicians.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.11 no.10
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• pp.4948-4967
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• 2017

On mobile devices, image sequences are widely used for multimedia applications such as computer vision, video enhancement, and augmented reality. However, the real-time processing of mobile devices is still a challenge because of constraints and demands for higher resolution images. Recently, heterogeneous computing methods that utilize both a central processing unit (CPU) and a graphics processing unit (GPU) have been researched to accelerate the image sequence processing. This paper deals with various optimizing techniques such as parallel processing by the CPU and GPU, distributed processing on the CPU, frame buffer object, and double buffering for parallel and/or distributed tasks. Using the optimizing techniques both individually and combined, several heterogeneous computing structures were implemented and their effectiveness were analyzed. The experimental results show that the heterogeneous computing facilitates executions up to 3.5 times faster than CPU-only processing.

• Proceedings of the IEEK Conference
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• 1998.10a
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• pp.491-494
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• 1998

This paper describes the design and implementation of file system which allows the collaborative computing in mobile environment. The design goal is to make a logically one file system in the distributed computer systems. The characteristics of frequent, foreseeable and variable disconnections in a mobile environment wrer taken into consideration. We introduce an auto-hoarding system that provides the availability of large number of nodes which are weakly and intermittently connected. The data consistency problems in distributed or replicated mobile data are also discussed.

• Journal of information and communication convergence engineering
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• v.6 no.3
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• pp.348-352
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• 2008

In distributed computing paradigm, mobile surrogate systems migrates from on host in a network to another. However, Mobile surrogate system have not gained wide acceptance because of security concerns that have not been suitably addressed yet. In this paper, we propose a security framework based on Grid Proxy Gateway for mobile Grid service. The current Grid Security Infrastructure is extended to mobile computing environments. The surrogate host system designed for mobile Personal Digital Assistant (PDA) users can access the certified host and get his proxy credential to launch remote job submission securely.

• International Journal of Contents
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• v.2 no.4
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• pp.25-30
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• 2006

The mutual exclusion (MX) paradigm can be used as a building block in many practical problems such as group communication, atomic commitment and replicated data management where the exclusive use of an object might be useful. The problem has been widely studied in the research community since one reason for this wide interest is that many distributed protocols need a mutual exclusion protocol. However, despite its usefulness, to our knowledge there is no work that has been devoted to this problem in a mobile computing environment. In this paper, we describe a solution to the mutual exclusion problem from mobile computing systems. This solution is based on the token-based mutual exclusion algorithm.

• Journal of KIISE:Computing Practices and Letters
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• v.10 no.1
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• pp.75-88
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• 2004

Condor is a distributed batch system for sharing the workload among the computers connected by a network. Condor distributed system was developed on the basis that every machine in a Condor pool is always connected by a network to run a Condor Job. Due to advances in wireless communication and mobile computing technology, conventional distributed computer systems can now include “mobile” clients as well as “fixed” clients. Moreover, mobile users want to lower their power consumption by off-loading potentially power and resource consuming jobs. In this paper, we describe the design and implementation of mobile interface for mobile clients in Condor distributed batch system. The main purpose of this work is to enable users on mobile computers to interact with Condor environment any time anywhere regardless of their connection to a Condor pool. The mobile Condor distributed system also aims to provide mobile users the same Condor services without making any significant changes to the existing Condor system.

• Proceedings of the Korean Information Science Society Conference
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• 2006.10a
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• pp.326-330
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• 2006

배터리를 사용하는 소형 임베디드 시스템은 효과적인 전력관리가 필요하다. 그러나 현재까지 개발된 전력관리 기법들은 대부분 운영체제와 하드웨어를 대상으로 하고 있어 개발 플랫폼에 종속적인 특징을 갖는다. 따라서 시스템을 개발할 때마다 지원하는 전력관리 기법을 하드웨어나 운영체제에 따라 여러 번 개발을 해야 하는 단점이 있다. 본 논문에서는 하위 계층에서 지원하는 전력관리 기법에 관계없이 동일한 기능을 제공하는 웨어러블 컴퓨터용 전력관리 미들웨어를 설계하였다.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2000.10a
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• pp.368-371
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• 2000

The distributed object computing is possible to distributed computing on same or heterogeneous machine environment with growth of distributed computing and object-oriented technology. The typical of model, CORBA is int solved the interoperability in heterogeneous machine environment over the network But, the CORBA has a problem that the server is can't rely on request of client occurs network overhead by extinction of network A plan was on the rise to solve the problem that is combination of mobile agent and distributed computing technology.