• Journal of Korean Society for Quality Management
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• v.45 no.4
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• pp.933-942
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• 2017

Purpose: The purpose of this paper is to evaluate the performance quality of the open source DBMSs. Performance quality is defined as processing time for Join queries. Query processing time is measured and compared in the most widely used open source DBMSs and commercial DBMS. Methods: By varying the number of tuples of two relations to be joined, the average processing time(seconds) of a Join query in each DBMS was obtained experimentally. ANOVA and Tukey HSD test were used in order to compare the performance quality of DBMSs. Results: There was a significant difference between the performance qualities of the three DBMSs at all experimental levels where the number of tuples was 100, 1,000, 2,000, 10,000, and 50,000. As a result of the Tukey HSD test, two open source DBMSs (MariaDB, MySQL) were classified in the same group only at the tuple level of 100. The commercial DBMS (MS-SQL Server) belonged to another group. At level of more than 1,000 tuples, all three DBMSs belonged to different groups. Conclusion: Within the open source DBMS group, MariaDB showed the better performance quality except for a small number of tuples. Thus the results show that MariaDB can be the alternative to MySQL which is currently most widely used. Between open source DBMS and commercial DBMS groups, MS-SQL Server always shows the best performance quality, but the less number of tuples, the less the difference.

• Korean Journal of Agricultural and Forest Meteorology
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• v.22 no.3
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• pp.135-143
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• 2020

Shortwave radiation and sunshine hours (SHOUR) are important variables having many applications, including crop growth. However, observational data for these variables have low horizontal resolution, rendering its application to related research and decision making on f arming practices challenging. In the present study, hourly solar radiation data were physically generated using the Land-Atmosphere Modeling Package (LAMP) at the National Center f or Agro-Meteorology, and then daily SHOUR fields were calculated through statistical downscaling. After data quality evaluation, including case studies, the SHOUR data were added to the existing publically accessible LAMP daily database. The LAMP daily dataset, newly updated with SHOUR, has been provided operationally as input data to the "Gyeonggi-do Agricultural Drought Prediction System," which predicts agricultural weather disasters and field crop growth status.

• Journal of the Korean Geosynthetics Society
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• v.13 no.4
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• pp.133-141
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• 2014

This study was carried out to establish the database system by using the safety inspection and in-depth inspection results for infrastructures such as bridges, tunnels, dams, and water supplies. A classification system of each facility was proposed by standardizing items for inspection & diagnosis in order to automatize work process. Also, it justifies data structure based on database from pre-investigation to field survey, evaluation of facilities, and report making. In addition to this, it suggests improvement plans of relative regulations and guidelines such as Facility Management System(FMS), operational regulation, and inspection detailed guideline to make inspection result database of infrastructures which can be used effectively.

• Proceedings of the Korea Information Processing Society Conference
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• 2011.04a
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• pp.441-443
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• 2011

본 논문은 오디오 특징 분석을 기반으로 한 음악검색 방법에 대한 기술과 연구에 대한 내용이다. 본 연구에서는 크게 3가지의 주요 알고리즘을 이용하여 다 성음에서의 오디오 특징을 추출하고 3가지의 각자 다른 방식의 매칭 알고리즘을 기반으로 한 퓨전 매칭 방식을 제안한다. 오디오 특징으로는 메인 멜로디, 음악 구조를 분석한 세그먼테이션 정보를 이용한다. 본 연구에서 사용된 음악 DB는 음악 포털 서비스에서 제공하는 장르를 기반으로 한 8가지 장르에서 다양한 범위에서 2000곡을 선곡하였다. 오디오 특징 추출을 위한 알고리즘 개발과 매칭 알고리즘 개발을 위하여 음악 DB 2000곡 중 장르의 비율을 고려하여 100곡을 선정하고, 24명으로부터 1200개의 허밍을 녹음하였다. 24명중 3명은 대학에서 음악을 전공하고 나머지는 음악적 교육을 받은 경험이 없는 사람들이다. 1200개의 허밍을 분석한 결과 전체 허밍 중 60%정도가 노래의 시작 부분을 허밍하거나 노래를 불렀고, 30%정도는 하이라이트 부분을 허밍 하였다. 나머지 10%정도는 자신이 가장 자신 있는 부분을 불렀다. 이러한 분석 결과를 기반으로 가장 중요한 부분은 노래가 시작되는 부분에서의 멜로디를 정확하게 찾아내는 것이 무엇보다 중요하다는 것이다. 본 연구에서 검색결과의 평가는 MRR를 이용하여 측정하였다. MIDI DB를 사용한 경우가 다 성음에서 직접 멜로디를 추출한 경우보다 약간 성능이 우수하게 나왔으나 그 차이는 미미했다. 본 연구에서는 개발된 알고리즘을 이용하여 PC상에서 사용할 수 있는 클라이언트 프로그램과 Android app를 개발하였다.

• Proceedings of the Korean Society of Computer Information Conference
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• 2011.06a
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• pp.213-216
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• 2011

Cloud Network에서 Computing과 마찬가지로 원격지 전력IT기기에 대한 경제성과 산업기술에 대한 평가가 필요하다. 또한 Computer와 Network에서는 기술적인 연구가 필요하다. 본 연구에서는 원격지에서 전력IT기기 제품의 성능평가와 제품인증을 받기 위한 연구이다. 원격지 전력IT 기기의 제품별 기능, 모듈별 기능, 전력전송효율 평가값, 성능값, 허용오차 값 등의 대량 데이터가 존재하여, 전력IT 기기의 평가설계 및 DB, 웹환경에서 개발된 제조사, 평가기관, 인증기관의 주체가 원격지에서 실시간으로 표준화된 원격지 전력IT기기에 대한 평가 인증 프로세스와 평가 인증 값을 국제표준화에 맞출 수 있도록 연구한다.

• The Journal of the Korea Contents Association
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• v.16 no.1
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• pp.52-59
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• 2016

For almost of concrete structures by placing in cold weather, it is very important that the selection of curing method at early aged construction stage. The Exothermic curing method with hot wire and rapid hardening cement is used mostly to prevent the initial cracks and the strength decrease. Most of the construction sites, however, have not been applied to the optimal curing method caused by the simple approaches and the empirical judgements. Therefore, this paper has proposed a evaluation algorithm of the exothermic curing method for representing heating temperature, period, position of hot wire by analyzing the transient heat transfer solution. This has been implemented, moreover, using an object oriented programming language to develop structural analysis system taking account risk parameters. This system is composed of input module, database module, database store module, analysis module, and result generation module. Linkage interface between the central database and each of the related module is implemented by the visual c# concept. Graphic user interface and the relational database table are supported for user's convenience.

• Journal of KIISE:Software and Applications
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• v.31 no.7
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• pp.911-921
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• 2004

Accurate minutiae extraction from input fingerprint images is one of the critical modules in robust automatic fingerprint identification system. However, the performance of a minutiae extraction is heavily dependent on the quality of the input fingerprint images. If the preprocessing is performed according to the fingerprint image characteristics in the image enhancement step, the system performance will be more robust. In this paper, we propose a knowledge-based preprocessing method, which extracts S features (the mean and variance of gray values, block directional difference, orientation change level, and ridge-valley thickness ratio) from the fingerprint images and analyzes image quality with Ward's clustering algorithm, and enhances the images with respect to oily/neutral/dry characteristics. Experimental results using NIST DB 4 and Inha University DB show that clustering algorithm distinguishes the image Quality characteristics well. In addition, the performance of the proposed method is assessed using quality index and block directional difference. The results indicate that the proposed method improves both the quality index and block directional difference.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.26 no.1A
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• pp.35-43
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• 2006

In this paper, procedures and research results involved in the development of glass reinforced composite bridge deck of hollow section were presented. Laminate design for the 3 cell deck section was performed. Structural characteristics such as serviceability, strength, failure and stability for DB24 load were analytically studied through the finite element analysis for the composite deck plate girder bridge. Composite deck tube was fabricated with pultrusion and extensive tests such as flexural test, girder-connection test, barrier-connection test, compression fatigue test and flexural fatigue test were carried out to evaluate structural behavior experimentally. Also, field load test was conducted for the demonstration plate girder bridge with composite deck and requirements for the strength and serviceability were reviewed.

• KASI NEWSLETTER
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• s.38
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• pp.1-4
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• 2003

연구회 현장평가 실시/KAO Vision21 최종 총괄위원회 개최/제11회 천체사진공모전 개최/ 2003 별의 축제 개최/김종수 박사, 이달의 과학기술자상 수상/천문우주정보센터 DB 색인 1단계 구축 완료/PC 클러스터 32대 구축 완료/한국가상천문대 구축 현황/식목행사 실시/학회동정/인사발령/승진발령/브레인풀 임용/직원동정/콜로키움/호주 Mount Stromlo 천문대의 화재

• Journal of the Korean Society for Precision Engineering
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• v.23 no.7 s.184
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• pp.14-23
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• 2006