• Journal of the Korea Institute of Information and Communication Engineering
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• v.15 no.5
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• pp.1105-1110
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• 2011

It is possible to synchronize the spatio-temporal data with a server using a wireless network. These data has the benefit to be up-to-date and able to service to the user efficiently. However, the mobile devices or the wireless network are very vulnerable to various hard or soft failures. If an failure occurs during a synchronization process, the spatio-temporal data which is synchronizing could be inconsistent state. In this paper, we propose the recovery scheme to solve the problem caused by the errors which occur during the synchronization on mobile environments. The proposed scheme writes the log records for the synchronization process into the both local storages of the server and the mobile client. When the errors arise, the data which are synchronizing are recovered using the written log records. Also, we design and implement the proposed recovery scheme on the synchronization system.

• Journal of Korean Library and Information Science Society
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• v.54 no.1
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• pp.25-44
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• 2023

This study was to prepare a development plan for nationwide authority control system based on national authority sharing system of NLK through the survey targeting on libraries which do not participate in the system. Six plans were suggested to establish a nationwide authority control system based on this survey. First, an authority data construction module and a module linked to the national authority sharing system should be developed. Second, describing external identifiers such as ISNI to the national authority sharing system is to provides reliability of data and to utilizes to build linked data. Third, it is necessary to prepare strategies for promoting the national authority sharing system and diversifying services. Fourth, both authority establishment and non-establishment show difficulties and diversity in the selection and description of authorized access point, so it is necessary to prepare rules related to authorized access points. Fifth, since the data described in authority records is not enough, it is necessary to improve and upgrade authority records by using bibliographic records. Sixth, it is necessary to educate librarians about the necessity and function of authority control. As such, this study is meaningful in that it investigated the current status and requirements of libraries that do not participate in the nationwide authority system and sought ways to establish a nationwide cooperative authority control system.

• Journal of the Korea Society of Computer and Information
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• v.20 no.5
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• pp.1-12
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• 2015

NAND flash memory has being used for storage systems widely, because it has good features which are low-price, low-power and fast access speed. However, NAND flash memory has an in-place update problem, and therefore it needs FTL(flash translation layer) to run for applications based on hard disk storage. The FTL includes complex functions, such as address mapping, garbage collection, wear leveling and so on. Futhermore, implementation of the FTL on low-power embedded systems is difficult due to its memory requirements and operation overhead. Accordingly, many index data structures for NAND flash memory have being studied for the embedded systems. Overall performances of the index data structures are enhanced by a decreasing of page write counts, whereas it has increased page read counts, as a side effect. Therefore, we propose an index management method using a page mapping log table in $B^+$-Tree based on NAND flash memory to decrease page write counts and not to increase page read counts. The page mapping log table registers page address information of changed index node and then it is exploited when retrieving records. In our experiment, the proposed method reduces the page read counts about 61% at maximum and the page write counts about 31% at maximum, compared to the related studies of index data structures.

• Journal of the Korean Society for information Management
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• v.26 no.1
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• pp.163-184
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• 2009

This study is aimed to develop standard metadata model and develop elements and present the importance of oral history archives that contrast with literature history. The study analyzed standard metadata description elements that can express contents and forms of oral history archives as information. Furthermore, it designed Project, Management, Record, and metadata modeling as a Related record domain for the sake of building digital oral archives. Finally, the study gave shape to real oral history archives based on basic elements, details, and design principles of division elements.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2010.05a
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• pp.686-688
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• 2010

The supply of context information is increasing with the propagation of ubiquitous computing environment. Recently, as context information is being collected through electronic tags and sensors attached to the environment, we need methods to efficiently store and search large volumes of data. This paper describes the application of the RLE (Run Length Encoding) compression method for sensors that continuously collect data in USN/RFID terminals.Time information is marked on the data and one data block is generated and saved. This paper proposes a storage method that allows us to quickly search data of the desired time and place by recording time information in continuous data.

• Journal of the Korean Society for Library and Information Science
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• v.53 no.1
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• pp.109-132
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• 2019

The purpose of this study is to examine and propose to improve the features of a simple keyword search box and faceted navigations of KOLIS-NET operated by the National Library of Korea. A record group of '2011-2020 (776)' under 'Publication date' facet, out of 3,702 records retrieved from a search of '김훈', were examined. Major findings are as follows: (1) Five facets including 'Format', 'Publication date', 'Subject', 'Language' and 'Country' are used to limit search results only in the first step, and multiple facets cannot be simultaneously used; (2) With 'Publication date' facet formed in the span of ten years, a separate publication year cannot be identified; (3) 'Subject' facet based on KDC limits the results only in broad subject classes without sub-facets; (4) Under 'Format' facet, a special format such as large print texts cannot be identified; (5) Without 'Author' facet, authors cannot be identified; and (6) 'Publication date missing', 'Language missing', and 'Miscellaneous subject' record groups cannot be clicked and displayed, a navigation to-and-fro between a brief list and bibliographic records is not smooth, etc. Therefore an application of multiple facets in all stages of limiting the search result, a construction of sub-facets for 'Publication date' and 'Subject' facets, an accurate description and coding of 'General Material Designation', etc. are suggested to improve KOLIS-NET's faceted navigation.

• Proceedings of the Korean Society of Computer Information Conference
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• 2020.01a
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• pp.65-66
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• 2020

이 논문에서는 NTFS 파일시스템에서 여러 개의 클러스터에 걸쳐서 슬랙 영역에 데이터 숨기기를 수행하는 데이터 숨기기 방법의 강인성을 조사하기 위하여 디스크 조각모음 실험을 수행할 때 필요한 방법을 제안한다. 디스크 조각모음의 실행으로 클러스터의 위치가 변동되기 위해서는 여러 클러스터에 걸친 디스크 조각의 단편화가 일어날 수 있도록 파일을 생성하고 삭제하는 작업을 수행한다. 그 후에 용량이 큰 파일을 복사하여 여러 클러스터에 걸친 단편화된 파일을 작위적으로 생성한다. 단편화된 파일만을 남기고 그 이외의 다른 파일들을 삭제한 후에 디스크조각 모음을 수행한다. 이 실험에 필요한 준비과정과 실험과정을 제안한다.

• Proceedings of the Korea Contents Association Conference
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• 2007.11a
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• pp.414-417
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• 2007

Citation matching (CM) is a method for clustering citation records that refer to the same paper. Normally, CM is preceded by citation field segmentation (CFS) which divides a citation record into its fields such as author(s), a title, a title of publication, year, etc. Although many studies have attacked CFS and CM, the relationship between CFS and CM was not sufficiently explored. Among many aspects of the effect of CFS on CM, this study concentrates on what citation fields should identify for CM. As its first attempt, we compared CM performances over different sets of citation fields manually segmented, and confirmed that the use of more citation fields help CM to cluster citation records better.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.7
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• pp.293-300
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• 2016

Traditional databases exploit a record-based model, where the attributes of a record are placed contiguously in a slow hard disk to achieve high performance. On the other hand, for read-intensive data analysis systems, the column-based compressed database has become a proper model because of its superior read performance. Currently, flash memory SSD is largely recognized as the preferred storage media for high-speed analysis systems. This paper introduces a compressed column-storage model and proposes a new index and its data management scheme for a high-capacity data warehouse system. The proposed index management scheme is based on the asymmetric index duplication and achieves superior search performance using the master index and compact index, particularly for large read-mostly databases. In addition, the data management scheme contributes to the read performance and high reliability by compressing the related columns and replicating them in two mirrored SSD. Based on the results of the performance evaluation under the high workload conditions, the data management scheme outperforms the traditional scheme in terms of the search throughput and response time.

• Journal of the Korean Society for information Management
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• v.37 no.2
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• pp.197-223
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• 2020

The purpose of this study is to analyze the issues resulted from the process of grouping KORMARC records using FRBR WORK concept and to suggest a new method. The previous studies did not sufficiently address the criteria or processes for identifying representative authors of records and their derivatives. Therefore, our study focused on devising a method of identifying the representative author when there are multiple contributors in a work. The study developed a method of identifying representative authors using an author role dictionary constructed by extracting role-terms from the statement of responsibility field (245). We also designed another way to group records as a work by calculating similarity measures of authors and titles. The accuracy rate of WORK grouping was the highest when blank spaces, parentheses, and controling processes were removed from titles and the measured similarity rates of authors and titles were higher than 80 percent. This was an experiment study where we developed an author-role dictionary that can be utilized in selecting a representative author and measured the similarity rate of authors and titles in order to achieve effective WORK grouping of KORMARC records. The future study will attempt to devise a way to improve the similarity measure of titles, incorporate FRBR Group 1 entities such as expression, manifestation and item data into the algorithm, and a method of improving the algorithm by utilizing other forms of MARC data that are widely used in Korea.