• Journal of the Korea Society of Computer and Information
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• v.22 no.2
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• pp.1-7
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• 2017

Recently, NAND flash memory, which is used as a storage medium, is replacing HDD (Hard Disk Drive) at a high speed due to various advantages such as fast access speed, low power, and easy portability. In order to apply NAND flash memory to a computer system, a Flash Translation Layer (FTL) is indispensably required. FTL provides a number of features such as address mapping, garbage collection, wear leveling, and hot data identification. In particular, hot data identification is an algorithm that identifies specific pages where data updates frequently occur. Hot data identification helps to improve overall performance by identifying and managing hot data separately. MHF (Multi hash framework) technique, known as hot data identification technique, records the number of write operations in memory. The recorded value is evaluated and judged as hot data. However, the method of counting the number of times in a write request is not enough to judge a page as a hot data page. In this paper, we propose hot data identification which considers not only the number of write requests but also the persistence of write requests.

• The KIPS Transactions:PartC
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• v.18C no.4
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• pp.199-206
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• 2011

Removable Storage provides the excellent portability with light weight and small size which fits in one's hand, many users have recently turned attention to the high-capacity products. However, due to the easy of portability for Removable Storage, Removable Storage are frequently lost and stolen and then many problems have been occurred such as the leaking of private information to the public. The advent of remote storage services where data is stored throughout the network, has allowed an increasing number of users to access data. The main data of many users is stored together on remote storage, but this has the problem of disclosure by an unethical administrator or attacker. To solve this problem, the encryption of data stored on the server has become necessary, and a searchable encryption system is needed for efficient retrieval of encrypted data. However, the existing searchable encryption system has the problem of low efficiency of document insert/delete operations and multi-keyword search. In this paper, an efficient searchable encryption system is proposed.

• Journal of the Korea Society of Computer and Information
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• v.22 no.9
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• pp.1-8
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• 2017

In this paper, we propose a file system for flash memory which remedies shortcomings of existing flash memory file systems. Besides supporting large block size, the proposed file system reduces time in initializing file system significantly by adopting logical address comprised of erase block number and bitmap for pages in the block to find a page. The file system is suitable for embedded systems with limited main memory since it has small in-memory data structures. It also provides efficient management of obsolete blocks and free blocks, which contribute to the reduction of file update time. Finally the proposed file system can easily configure the maximum file size and file system size limits, which results in portability to emerging larger flash memories. By conducting performance evaluation studies, we show that the proposed file system can contribute to the performance improvement of embedded systems.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 2005.10a
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• pp.371-387
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• 2005

From early 1999 years, the Mobile Telecommunication Companies have introduced the Mobile Telecommunication Membership Program to attract more customers. However, the severe competition in the Mobile Telecommunication market has made the Mobile Telecommunication Membership Program to be faced with the matured Mobile Telecommunication market and the Mobile Number portability. Main focus of this study is to find what are the core elements of service quality of the Mobile Telecommunication Membership Program. To achieve research objective, we conceptualized the service quality of Mobile Telecommunication Membership Program. We also derived hypotheses regarding the relationships between service quality of the program, customer satisfaction, and customer loyalty and examined it by using the empirical research methodology. We suggest new marketing strategies of the Mobile Telecommunication Membership Program which can be applied to improve the corporate competitiveness.

• Proceedings of the Korean Information Science Society Conference
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• 2007.06d
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• pp.220-224
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• 2007

번호이동성은 이용자가 사업자, 위치, 서비스 등을 변경하더라도 기존에 사용하던 전화번호를 그대로 사용 할 수 있도록 하는 제도로써 통신 산업의 경쟁을 활성화하고 이용자의 편익을 증진시키기 위해 도입되었다. 현재는 시내전화 내 또는 이동전화 내에서와 같이 단일 역무 내에서만 번호이동성이 시행되고 있지만, 광대역통합망(BcN)과 같은 IP기반의 컨버전스 네트워크 상의 번호이동성에서는 URI 기반 라우팅, 이종 역무간 번호이동과 같은 고려사항이 발생하게 된다. 본 고에서는 BcN 상의 번호이동 시스템을 구현하기 위한 ENUM DNS 활용방안을 제시하고자 한다.

• Korean Management Science Review
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• v.23 no.1
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• pp.115-133
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• 2006

From early 1999 years, the mobile telecommunication companies have introduced the mobile telecommunication membership program to attract more customers. However, the severe competition in the mobile telecommunication market has made the mobile telecommunication membership program to be faced with the matured mobile telecommunication market and the mobile number portability. Wain focus of this study is to find what are the core elements of service qualify of the mobile telecommunication membership program. To achieve research objective, we conceptualized the service quality of mobile telecommunication membership program. We also derived hypotheses regarding the relationships between service quality of the program, customer satisfaction, and customer loyalty and examined it by using the empirical research methodology. We suggest new marketing strategies of the mobile telecommunication membership program which can be applied to improve the corporate competitiveness.

• Korean Management Science Review
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• v.21 no.2
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• pp.235-252
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• 2004

Recently domestic mobile carriers have been engaged in heated battles for survival as the market is now rapidly approaching its maturity phase. and the launch of 3G service combined with the introduction of mobile number portability is dramatically reshaping the market landscape. The mobile carriers may have to create and maintain their competitive advantage based on their core capabilities and differentiated strategies. which will lead continuous survival and profits of the firm. This paper investigated competitiveness factors among mobile carriers. and analyzed the relationships of firm capabilities. competitive strategies and competitive advantage. We found that core capabilities and competitive strategies affecting competitive advantage are different from each carrier. Finally. we discussed strategic implications for carriers to increase their competitiveness.

• The Transactions of the Korea Information Processing Society
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• v.5 no.12
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• pp.3214-3220
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• 1998

국내 차세대 지능망은 ITU-T IN CS-1 권고안을 근간으로 개발 중에 있으며, 한국통신은 1999년부터 UPT, VOT서비스를 상용화할 예정이다. 다양한 통신서비스를 제공하기 위해 국내에서는 많은 통신 사업자들이 등장하였고 사용자 요구를 만족시키기 위해 사업자간 경쟁하고 있다. 번호 이동성 문제는 통신시장의 경쟁 구도를 지향하고 있는 국내 통신 환경에서도 앞으로 중요한 문제로 대두될 것이다. 따라서, 본 논문에서는 차세대 지능망을 이용하여 번호이동성을 제공하는 방식을 살펴보고, 개발 중인 차세대 지능망 시스템을 이용하여 각 통신사업자마다 번호이동성을 구현하는 효율적인 방안을 제안한다.

• Proceedings of the Korea Information Processing Society Conference
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• 2000.10b
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• pp.1549-1552
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• 2000

경쟁이 도입된 통신시장에는 사업자간에 공정경쟁을 촉진하고 가입자에게는 사업자 선택의 폭을 증대시켜 주는 서비스제공자 번호이동성이 도입되고 있다. 이동전화시장에도 최근 영국을 비롯한 선진 통신국을 중심으로 번호이동성 서비스를 제공 중에 있다. 본 논문에서는 이동전화의 번호이동성 제공기술들을 살펴보고, ETSI 에서 표준화하고 있는 네트워크 solution의 요구기능을 검토하여 이동전화의 번호이동성 제공기술의 장.단점을 비교 분석하였다. 또한 국내 도입 시 바람직한 기술적 제공방안이 선택될 수 있도록 국내 적용을 위한 사전 고려사항을 제시하였다.

• Electronics and Telecommunications Trends
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• v.17 no.4 s.76
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• pp.39-50
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• 2002

번호이동성은 전화가입자가 사업자, 지역 및 서비스를 바꾸어도 기존에 사용하고 있는 자신의 전화번호를 그대로 유지할 수 있도록 하는 제도이다. 경쟁적인 측면에서 이동전화 번호이동성은 로밍 서비스와 함께 이동전화시장의 소매 가입부문의 경쟁을 촉진할 수 있다. 우리나라의 경우 2001년 1월 8일에 개정된 전기통신사업법에서 번호이동성의 국내 도입과 관련된 사항들을 규정하였다. 유선전화 번호이동성의 경우 2003년 말부터 구현이 가능한 지역부터 제공할 예정이며, 이동전화 번호이동성의 경우 3G 서비스부터 먼저 실시할 계획으로 복수의 사업자가 3G 서비스를 개시한 이후 6개월 이내부터 도입할 예정이다. 본 연구에서는 이동전화 번호이동성의 도입에 가장 적극적인 유럽의 주요 국가들과 호주의 사례를 검토하여 국내 이동전화 번호이동성 정책의 수립에 적용될 수 있는 시사점을 도출하고자 한다.