• Journal of KIISE:Computer Systems and Theory
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• v.29 no.7
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• pp.369-376
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• 2002

Although LRU is not adequate for database that has non-uniform reference pattern, it has been adopted in most database systems due to the absence of the proper alternative. We analyze database block reference pattern with the realistic database trace. Based on this analysis, we propose a new cache replacement policy. Trace analysis shows that extremely non-popular blocks take up about 70 % of the entire blocks. The influence of recency on blocks' re-reference likelihood is at first strong due to temporal locality, however, it rapidly decreases and eventually becomes negligible as stack distance increases. Based on this observation, RCB(Reference Characteristic Based) cache replacement policy, which we propose in this paper, classifies the entire blocks into four block groups by blocks' recency and re-reference likelihood, and operates different priority evaluation methods for each block group. RCB policy evicts non-popular blocks more quickly than the others and evaluates the priority of the block by frequency that has not been referenced for a long time. In a trace-driven simulation, RCB delivers a better performance than the existing polices(LRU, 2Q, LRU-K, LRFU). Especially compared to LRU. It reduces miss count by 5~l2.7%. Time complexity of RCB is O(1), which is the same with LRU and 2Q and superior to LRU-K(O(log$_2$N)) and LRFU(O(l) ~ O(log$_2$N)).

• Journal of the Economic Geographical Society of Korea
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• v.17 no.2
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• pp.385-401
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• 2014

This research analyses spatial and temporal characteristics of the academic performances of high school students by using all 2,065,166 SAT scores for 3 years. The spatial inequalities in Seoul are analysed by DBMS and GIS. Based on three-year raw data of Korean SAT scores, the spatial and temporal characteristics of academic performances are scrutinized: 868,029 SAT scores cases of 2000 academic year on Novemver 17, 1999, 609,258 cases in 2005 academic year on November 17, 2004 and 587,890 cases in 2009 on November 13. The result shows that there are significant spatial disparities of the level of academic performance in Seoul by Gu level, also indicating that the disparities are getting wider over the course of time. The widening disparities by Gu level means that educational spatial inequality is intensified in spite of the increasing overall trend of academic performance of Seoul. It is also notable that disparities between regions are distinctive, while those in regions are not significant and sustained constant as time flows.

• Journal of Korean Society of Environmental Engineers
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• v.27 no.12
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• pp.1340-1346
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• 2005

A water quality modeling study was performed for Chunggye stream during combined sewer overflow(CSO) period, utilizing the diagnostic system for water management in small watershed, CREEK-1(Cyber River for Environment and Economy in Korea). This system integrated geogaphic information system, data base, landscape ecological model(FRAGSTATS), watershed model(SWMM), water quality model (WASP5), and computer graphic. In this study, the watershed model and water quality model were extensively utilized so as to simulate water qualities and flow in Chunggye stream during wet periods. The Chunggye stream watershed was divided into 18 sub-basins in the watershed model and the stream reach into 11 segments in the water quality model. The watershed model was validated against field measurements of BOD, TN, TP, and flow at the downstream location, where the model results showed a reasonable agreement with the field measurements at all parameters. From this study, it was shown that the stream water quality would change along with elapsed time from rainfall start as well as rainfall intensity. The model results indicated that the water quality would significantly upgrade due to the first flush and high sewage ratio of CSO at the beginning of rainfall event, but become degraded along with the runoff increase due to dilution effect.

• Journal of Korean Library and Information Science Society
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• v.36 no.2
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• pp.263-281
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• 2005

This study was to elucidate the theoretical backgrounds and realities of consumer health information services from a review of the literature, to manifest the actual conditions of consumer health information services by domestic hospital libraries and public libraries, and then to activate library services at least to meet the needs of the services by enhancing their role for consumer demand for health information. This paper propose to activate consumer health information services, as follows : First, librarians both in hospital and in public libraries cognize that consumer health information services really are needed. Furthermore, they expect that when consumer health information services are implemented, the function of the library would be expanded even to the realm of preventive health medical care for consumers and as well as to the patients' right to know. Second, it is recommended that hospital libraries should actively perform their consumer health information services, along with the active collection of health information and materials and develop related bibliographies for hospital libraries to provide patients and their families with medical information. Public libraries also are required to actively collect, maintain and manage health information and to equip themselves with special books in their reference rooms. Third, it is recommended to launch such a cooperation network with a subsystem of MEDLIS as CHIN or CHIPS in the United States of America, to construct an integrated database of consumer health information and materials, an interlibrary system, a reference room service system as well as a cooperation network among hospital and public libraries.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.15 no.5
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• pp.1-7
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• 2015

Recently, a coaching helps individual to lead and maximize performance. Generally there is a face to face coaching at the current spot of education, and the e-coaching is on the rise. And the face-to-face coaching means that coach and the coachee come face to face directly. And, the effective coaching method is required to supply the weakness and to maximize the strength of the e-coaching using the Internet. Accordingly, we are studying a hybrid coaching to overcome the difficulty and the limit of face-to-face coaching and online coaching. In this paper, we design and implement the career coaching system to provide the face-to-face coaching and the e-coaching for coachee based on the Web service on the Internet. We provide the hybrid coaching using Web service based on the Restful and connect with the database based on the Web to save and manage the profiles and the coaching history of the coach and the coachee. Proposed hybrid coaching system for coachee career improves remote accessibility between the coach and the coachee. This system provides the interaction without the limit of the time and the space, and overcomes the limit of the traditional face-to-face coaching on the online environment.

• Journal of the Korean Institute of Intelligent Systems
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• v.22 no.2
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• pp.141-147
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• 2012

The purpose of the study is the acquisitions of knowledge related in job searching from local companies and job seekers using data mining techniques. At the first step, for the study, we had selected the local companies their headquarters are located in Jeonbuk province. Then we had picked the graduating students out from the high schools, colleges, and universities in the same area as the job seekers. After the targeting of the sample, we had surveyed 560 local companies and 14 schools for the collecting of the preliminary data. As the result of the survey, we could collect 173 responses from the companies and 551 responses from the job seekers. At the second step using data mining, we had adapted the C5.0 algorithm to extract the inference rules. Then we had used the Visual Basic (VB) programming language to visualize the rules at the third step. At the fourth step, we transformed the inference rules into DB tables. At the final step, we had executed the rule inferences to support the development of the long-term human resources development (HRD) strategies. As the result of the study, we could suggest the helpful information to the HRD directors and job seekers in designing their strategies in managing their jobs and career development.

• Journal of the Korean Association of Geographic Information Studies
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• v.20 no.4
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• pp.24-38
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• 2017

The awareness and demand for technological elements in the field of cloud computing and their application models have increased. Cloud-based service information systems are being expanded for use in many applications. Advancements in information technology are directly related to spatial information. PaaS is an important platform for implementing a substantial cloud ecosystem to develop geo-based application services. For this reason, it is necessary to analyze the PaaS cloud technology prior to the development of SaaS. The PaaS cloud supports sharing of related extensions, database operations and management, and application development and deployment. The development of geo-spatial information systems or services based on PaaS in ranging the domestic and overseas range is in the initial stages of both research and application. In this study, state-of-the-art cloud computing is reviewed and a conceptual design for geo-based applications is presented. The proposed model is based on container methods, which are the core elements of PaaS cloud technology based on open source. It is thought that these technologies contribute to the applicability and scalability of the geo-spatial information industry that addresses cloud computing. It is expected that the results of this study will provide a technological base for practical service implementation and experimentation for geo-based applications.

• Journal of KIISE:Computing Practices and Letters
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• v.8 no.1
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• pp.96-106
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• 2002

this paper, we propose a flexible, reusable, and extensible HL7 encoding and decoding framework using a Message Object Model (MOM) and Message Definition Repository (MDR). The MOM provides an abstract HL7 message form represented by a group of objects and their relationships. It reflects logical relationships among the standard HL7 message elements such as segments, fields, and components, while enforcing the key structural constraints imposed by the standard. Since the MOM completely eliminates the dependency of the HL7 encoder and decoder on platform-specific data formats, it makes it possible to build the encoder and decoder as reusable standalone software components, enabling the interconnection of arbitrary heterogeneous hospital information systems(HISs) with little effort. Moreover, the MDR, an external database of key definitions for HL7 messages, helps make the encoder and decoder as resilient as possible to future modifications of the standard HL7 message formats. It is also used by the encoder and decoder to perform a well formedness check for their respective inputs (i. e., HL7 message objects expressed in the MOM and encoded HL7 message strings). Although we implemented a prototype version of the encoder and decoder using JAVA, they can be easily packaged and delivered as standalone components using the standard component frameworks like ActiveX, JAVABEAN, or CORBA component.

• Proceedings of the Korean Information Science Society Conference
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• 2004.04b
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• pp.58-60
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• 2004

웹의 확산과 더불어 웹 페이지 검색의 성능 즉, 빠른 응답시간과 확장성(scalability)은 각 웹 사이트의 절대적 평가 기준이 되었다. 웹 옹용은 일반적으로 불특정 다수를 대상으로 하기 때문에 확장성 또한 주요 성능의 척도가 된다. 이와 같은 웹 사이트 성능을 담보하기 위한 대표적 요소기술이 웹 캐슁이다. 본 논문은 웹 상에서 XML 데이터베이스 기반의 웹 응용(XML database-backed web application)을 위한 응용서버의 XML 캐쉬를 이용하여 주어진 XML 질의를 변환, 처리하는 기법과 구현에 관한 것으로 XPath의 경로표현식 중 가장 중요한 세 가지 기능인 조건을 명시하는 필터 연산자, 부모-자식 관계를 나타내는 경로 연산자(/), 그리고 조상-후손 관계를 나타내는 경로 연산자(//)를 연구 범위로 하였다. [2]에서는 조상-후손 관계를 나타내는 경로 연산자(//)가 없는 경우에 경로표현식으로 주어진 XML 질의를 캐쉬를 이용하여 변환, 처리하는 알고리즘을 제시하였는데 본 논문에서는 [2]의 알고리즘을 확장하여 경로 연간자(//)가 지원되도록 하였다. 조상-후손 경로 연산자(//)로는 정규경로 표현식(regular path expression)을 나타낼 수 있는데 이는 스키마가 불확실한 반구조적 데이터인 XML 데이터에 대한 질의 표현에 유용하다. 제시된 알고리즘에서는 DTD를 이용하여 경로 정보를 얻어 처리함으로써 주어진 질의를 캐쉬와 하부 XML 소스에 대한 질의로 변환하였다. 이 알고리즘을 바탕으로 관계 DBMS를 이용하여 구현된 시스템으로 실제 웹 상에서 성능 실험을 수행하였다. 성능 실험 결과 정규 경로 표현식을 포함하는 XML 질의에 대해서도 웹에서 캐쉬를 이용한 처리가 효율적임을 확인하였다.키는데 목적이 있다.RED에 비해 향상된 성능을 보여주었다.웍스 네트워크상의 다양한 디바이스들간의 네트워크 다양화와 분산화 기능을 얻을 수 있었고, 기존의 고가의 해외 솔루션인 Echelon사의 LonMaker 소프트웨어를 사용하지 않고도 국내의 순수 솔루션인 리눅스 기반의 LonWare 3.0 다중 바인딩 기능을 통해 저 비용으로 홈 네트워크 구성 관리 서버 시스템 개발에 대한 비용을 줄일 수 있다. 기대된다.e 함량이 대체로 높게 나타났다. 점미가 수가용성분에서 goucose대비 용출함량이 고르게 나타나는 경향을 보였고 흑미는 알칼리가용분에서 glucose가 상당량(0.68%) 포함되고 있음을 보여주었고 arabinose(0.68%), xylose(0.05%)도 다른 종류에 비해서 다량 함유한 것으로 나타났다. 흑미는 총식이섬유 함량이 높고 pectic substances, hemicellulose, uronic acid 함량이 높아서 콜레스테롤 저하 등의 효과가 기대되며 고섬유식품으로서 조리 특성 연구가 필요한 것으로 사료된다.리하였다. 얻어진 소견(所見)은 다음과 같았다. 1. 모년령(母年齡), 임신회수(姙娠回數), 임신기간(姙娠其間), 출산시체중등(出産時體重等)의 제요인(諸要因)은 주산기사망(周産基死亡)에 대(對)하여 통계적(統計的)으로 유의(有意)한 영향을 미치고 있어 $25{\sim}29$세(歲)의 연령군에서, 2번째 임신과 2번째의 출산에서 그리고 만삭의 임신 기간에, 출산시체중(出産時體重) $3.50{\sim}3.99kg$사이의 아이에서 그 주산기사망률(周産基死亡率)이 각각 가장 낮았다. 2. 사산(死産)과 초생아사망(初生兒死亡)을 구분(區分)하여 고려해 볼때 사산(死産)은 모성(母性)의 임신력(

• Journal of Navigation and Port Research
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• v.46 no.6
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• pp.525-529
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• 2022

In the eLoran system, the Loran Data Channel (LDC) is used to provide precise timing and positioning. The LDC message can be modulated with the Eurofix method, which modulates the transmission time of the 3rd-8th pulse not used for navigation, and the 9th pulse method, which modulates data using the 9th additional pulse after the existing 8 Loran pulses. In this paper, we analyzed the reception performance of the LDC message transmitted from the eLoran transmitter according to the modulation method. The eLoran testbed transmitter in Incheon was set to transmit LDC messages simultaneously with the 9th pulse modulation method and the Eurofix modulation method. Then, the LDC messages stored in the databases of the eLoran differential stations in Incheon and Pyeongtaek were analyzed in terms of the message reception rate according to the modulation method. Using the navigation aid management ship Inseong No. 1, the range of LDC message reception of actual sea users near Incheon Port was also analyzed. The results of this study are expected to be utilized in the full operational capability service after the eLoran pilot service.