• Proceedings of the Korean Information Science Society Conference
• /
• 2010.06b
• /
• pp.318-323
• /
• 2010

최근 병원이 주체가 되어 유비쿼터스 인프라를 구축하여, 이를 기반으로 병원 구성원뿐만 아니라 환자에 이르기까지 다양한 병원 정보 서비스를 제공하기 위한 연구와 시범사업이 이루어지고 있는 추세이다. 본 논문에서는 u-병원 환경에서 위치기반 가이드 시스템을 제안한다. 제한한 시스템의 소프트웨어 구조는 기존 연구되었던 분산객체그룹프레임워크(Distributed Object Group Framework)와 JADE(Java Agent DEvelopment Framework)를 기반으로 한다. 특히, RFID를 이용한 실내 위치 추적 기술과 본 연구실에서 연구해온 분산 프레임워크를 바탕으로 병원을 대상으로 하여 환자의 위치에 따르는 각 검사실의 위치와 검사에 필요한 정보를 제공한다. 이를 위해 시스템을 구성하는 전체 시스템 구조와 구성요소 간 상호작용에 대해 기술하였다. 그리고 물리적인 환경을 보이고 시스템의 수행과정을 모바일 디바이스상의 사용자 GUI를 통해 보였다.

• The KIPS Transactions:PartA
• /
• v.11A no.6
• /
• pp.419-424
• /
• 2004

Mobile Internet using mobile devices provides Portability to users and is Spreading throughout out lives. But Practical use of the mobile Internet is insufficient due to it's fundamental limitations. Especially, mobile resources are not sufficient because they are not closely connected under current mobile Internet services which are provided with pre-designed structure. For these reasons it will take a lot more time and effort for mobile Internet to grow as a popular service. In this paper, we are focusing to overcome the local limitation and to enhance the 'Sharing of Mobile Resources' by expanding mutual connectivity between resource objects scattered over the mobile Internet environment. To archive this, we propose the MRSS(Mobile Resources Sharing System). MRSS automatically converts single request from user to multiple instructions based on 'Context-Awareness' to search for proper information. Using MRSS, we can expect 'Mobile Ubiquitous Computing' environment which users can reach to information anywhere, anytime.

• The Journal of the Institute of Internet, Broadcasting and Communication
• /
• v.12 no.6
• /
• pp.33-42
• /
• 2012

Rapid evolution of wired and wireless technologies results in various types of embedded systems, and the software to be embedded into those devices now needs the flexibility rather than the fixedness which was well-known property for the embedded software in the past. Mobile agent is one of the useful distributed technologies of reducing network load and latency because of its disconnected operations and high asynchrony. In this paper, a component-based mobile agent framework, called EmHUMAN, is designed and implemented for structural embedding into the devices showing different functions and resource constraints. It consists of 3 layers of components. Based on those components, a structural embedding, considering resource constraints of required functions, amount of storage space, computing power, network bandwidth, ${\ldots} $ etc can be performed. The components in each layer can be extended with addition of new components, removing some components and modifying components. EmHUMAN plays the role of a framework for developing mobile agent based distributed systems. It is also a mobile agent system by itself. EmHUMAN provides several utilities as built-in API's, and thus high effectiveness in programming mobile agents can be achieved.

• Proceedings of the Korea Multimedia Society Conference
• /
• 2003.11b
• /
• pp.699-702
• /
• 2003

본 논문에서는 무선 인터넷 주요 기술로 관심을 받고 있는 분산데이터 동기화 표준인 SyncML을 이용한 개인정보관리 시스템의(PIMS) 설계 및 구현에 대한 소개하고자 한다. 객체 지향 설계 기법을 사용하여 분석, 설계하여 최적화 된 시스템을 도출하고 그것을 통해 우선인터넷상에서 경량화 된 동기화 최적의 시스템을 설계와 구현하는데도 목적이 있다. 특히 무선인터넷의 여러 제약 사항 특히 데이터의 관리에 있어서의 문제점을 동기화 기술을 통해 많은 데이터를 효과적으로 관리함으로써 대용량의 데이터 베이스와 디바이스에 상관없이 데이터 일관성을 유지하여 지연성 및 복수성에 신뢰성을 유지 할 수 있도록 시스템을 개발하였다.

• Journal of the Institute of Electronics Engineers of Korea TC
• /
• v.48 no.9
• /
• pp.17-26
• /
• 2011

Many types of services appear in a ubiquitous environment promulgated by the evolution of web service technology with the advances in wireless network technologies and mobile computing devices. These services differ according to their location environments, such as home, office, airport, and exhibition. It is required that a different set of services dynamically drops into the mobile user's device depending on their context and the distributed localized services are efficiently managed to seamlessly provide these localized services to the user. This paper proposes an Autonomic Service Composition System (ASCS) to provide useful services to the user with minimal or no effort for service selection. ASCS seamlessly installs the programs of localized services in the user's mobile device. It automatically provides localized services to users that are in the local service zone. Also ASCS can manage distributed localized services remotely and efficiently. ASCS is composed of a Remote Manager, Service Gateway, and Mobile Device. The prototype implementation uses 802.11b Wireless Network and Bundles using the OSGi Framework.

• Proceedings of the Korea Information Processing Society Conference
• /
• 2010.11a
• /
• pp.883-885
• /
• 2010

최근 무선통신기술의 발전으로 3G, WIFI, 그리고 블루투스와 같은 다양한 통신 인터페이스를 지닌 스마트폰이 등장하고 있다. 이러한 다양한 인터페이스를 동시에 활용하게 되면 보다 더 빠른 속도로 데이터를 송수신할 수 있다. 이러한 시스템의 대표적인 특징은 서버로 집중되는 트래픽을 분산시킬 수 있다는 것이다. 이러한 특징 때문에 최근 모바일 P2P 와 스트리밍 서버를 통한 동영상 스트리밍에 대한 연구가 활발히 진행되고 있다. 본 논문에서는 다양한 네트워크 인터페이스를 활용한 P2P 스트리밍 시스템을 제안한다. 제안하는 시스템은 모바일 피어들로 P2P 네트워크를 구성하고 3G 망을 이용하여 서버에 접속을 한다. 본 논문에서는 간단한 시나리오를 통하여 제안한 시스템의 성능을 분석하였다. 실험 결과, 시스템의 버퍼링은 44.0% 감소하였고, 에너지는 30.2% 적게 소모하였으며, 그리고 서버의 트래픽 사용량도 50.0% 감소시켰다.

• Journal of the Korea Society for Simulation
• /
• v.15 no.4
• /
• pp.21-28
• /
• 2006

In this paper, we introduce the mobile grid architecture using kernel-based managements. Mobile grid paradigm is used to allow mobile users to access distributed resources in a transparent, secure and effective way. Each mobile grid user requests job submission, searches for suitable resources to run Job, executes the job to the allocated system resources, and receives the results of the requested job. There are a number of challenging issues when taking mobile environment into account, such as limited performance of mobile devices and mobility of mobile device. To resolve these issues, we design and implement the kernel-based management system for mobile grid application to overcome the limited resources of mobile devices. Also, we show the efficiency of the suggested architecture using the performance evaluation.

• The KIPS Transactions:PartB
• /
• v.17B no.6
• /
• pp.413-420
• /
• 2010

In this paper, we propose a scheme for dynamic allocating network bandwidth based on the playback buffer levels of the clients in a distributed mobile multimedia system. In this scheme, the amount of bandwidth allocated to serve a video request depends on the buffer level of the requesting client. If the buffer level of a client is low or high temporarily, more or less bandwidth will be allocated to serve it with an objective to make it more adaptive to the playback situation of this client. By employing the playback buffer level based bandwidth allocation policy, fair services can also be provided to the clients. In order to support high quality video playbacks, video frames must be transported to the client prior to their playback times. The main objectives in this bandwidth allocation scheme are to enhance the quality of service and performance of individual video playback such as to minimize the number of dropped video frames and at the same time to provide fair services to all the concurrent video requests. The performance of the proposed scheme is compared with that of other static bandwidth allocation scheme through extensive simulation experiments, resulting in the 4-9% lower ratio of frames dropped according to the buffer level.

• The KIPS Transactions:PartD
• /
• v.15D no.3
• /
• pp.411-420
• /
• 2008

This paper implemented the u-Healthcare Context Information System (HCIS) supporting ubiquitous healthcare by using location, health and titrating environment information collected from sensors/devices equipped in home for healthcare home service. The HCIS is based on the Distributed Object Group Framework (DOGF), a management model which can customize distributed resources, and manages various context information, applications and devices as a group in healthcare home environment, as one more logical units. Also, this system provides continuous healthcare multimedia service considering a resident's location using Mobile Proxy, and the healthcare context information through Context Provider to a resident in home. For verifying execution of our system, we implemented the seamless multimedia service based on resident's location and the prescription/advice and schedule notification/alarm service as healthcare applications in home. And we showed the executing results of healthcare home service by using service device existed in the residential space on which the resident is located according to the healthcare scenario.

• Journal of the Korea Convergence Society
• /
• v.12 no.7
• /
• pp.45-51
• /
• 2021

In accordance with the rapid non-face-to-face environment and mobile first strategy, the explosive increase and creation of many structured/unstructured data every year demands new decision making and services using big data in all fields. However, there have been few reference cases of using the Hadoop Ecosystem, which uses the rapidly increasing big data every year to collect and load big data into a standard platform that can be applied in a practical environment, and then store and process well-established big data in a relational database. Therefore, in this study, after collecting unstructured data searched by keywords from social network services based on Hadoop 2.0 through three virtual machine servers in the Spring Framework environment, the collected unstructured data is loaded into Hadoop Distributed File System and HBase based on the loaded unstructured data, it was designed and implemented to store standardized big data in a relational database using a morpheme analyzer. In the future, research on clustering and classification and analysis using machine learning using Hive or Mahout for deep data analysis should be continued.