국가수준의 과학데이터 시각화 지원체계에 관한 연구

박동진,채균식,류범종,이상태,Park, Dong-Jin,Chae, Kyun-Shik,Ryu, Beom-Jong,Lee, Sang-Tae 한국과학기술정보연구원 과학기술정보센터 2011 Journal of Information Science Theory and Practice Vol.42 No.2

전통적으로 과학데이터 시각화는 데이터 분석과 관련이 깊은 연구 수행과정 중의 하나로 간주되어 왔다. 그러나 최근 들어서 과학데이터 시각화의 연구영역 자체가 독립적인 학문분야로서 자리를 잡기 시작하면서 시각화의 기술 및 방법들이 점차 고도화되고 복잡해지고 있다. 그러나 과학데이터 시각화 연구가 개인 및 그룹의 연구자들 스스로의 노력으로 시각화 문제를 해결하는 데 있어서 한계가 있다. 따라서 전문집단에 의한 체계적인 지원의 필요성이 대두되고 있으며, 본 연구는 거시적 관점의 국가수준에서 어떻게 과학데이터 시각화를 체계적으로 지원할 것인가를 정책적인 시각에서 분석하였다. 구체적으로 기존 문헌의 조사를 통하여 주요 성공요인들을 파악하였으며, 집중적으로 투자해야 할 연구의 영역을 설정하였다. 다음으로 국가수준의 시각화 연구지원의 전략적인 방향과 전략적 과제를 제언하였다. Conventionally, scientific data visualization is thought of as one of activities performed by scientists during the scientific data analysis. However, recently, there exits a set of research papers which count scientific data visualization as a independent research area. They show the research subjects for studying the scientific data visualization technology and methods. In case, a scientist or group of scientists can not solve their own visualization problem due to the unskillfulness and inexperience on using visualization tool. Therefore, it needs to help them by the systematic way for solving the problem. In this study, we analyze and propose the national level scientific visualization support system for scientists. In particular, we first analyze the existing papers and find out the critical success factors. Then, by integrating the findings of the analysis, we propose the research areas which need to be focused, and the strategic direction and specific research topics for scientific data visualization support system in national level.

ATM 망에서 인터넷 트래픽 성능 향상을 위한 GFR 통합 버퍼 관리 기법

정광일,김관웅,곽현민,김남희,정경택,채균식,전병실,Jeong Kwang-Il,Kim Kwan-Woong,kwak Hyun-min,Kim Nam-Hee,Chung Hyung-Taek,Chae Kyun-Shik,Chon Byoung-Sil 대한전자공학회 2004 電子工學會論文誌-TC (Telecommunications) Vol.41 No.1

GFR 서비스는 UBR의 단순성을 유지하면서 최소 전송율 보장, 잉여 대역의 공평한 할당 및 효율적인 링크 대역의 사용을 보장해야 한다. ATM에서 TCP 트래픽에 대응해서 만들어진 이러한 GFR 서비스 클래스의 효율적인 관리를 위해서는 ATM 스위치에서의 버퍼 관리가 필요하다. 제안된 버퍼 관리 알고리즘은 단일 FIFO에서 per-VC accounting 방식을 사용하며 GFR.1 및 GFR.2 모두를 수용할 수 있는 버퍼 관리 알고리즘이다. 제안된 알고리즘은 GFR.1 및 GFR.2를 차별적으로 다루기 위해서 CLP=0인 셀 수 및 CLP=1인 셀 수를 이용하여 버퍼 관리를 함으로써 GFR.1 VC들과 GFR.2 VC들에게 공평하게 잉여대역을 할당하여 사용함을 볼 수 있었으며, 전체 공평성 관점에서도 기존 알고리즘보다 우수한 성능을 보여주었다. As a new service category to better support TCP traffic in ATM networks, the Guaranteed Frame Rate (GFR) service category aims to support minimum cell rate guarantee, fairly distribute available bandwidth while keeping the simplicity of Unspecified Bit Rate (UBR). In this paper, we proposed a buffer management scheme which uses the per-VC accounting of single FWO queue and capable of supporting both GFR.1 and GFR.2 conformance definition. The proposed buffer management deal with GFR.1 and GFR.2 conformance definitions differentially by controlling the number of CLP=0 cell and CLP=1 cell which are occupying buffer space. The simulation results show that our proposed scheme satisfies the requirements of GFR services as well as improves total fairness index and each conformance definition fairness index.

참조표준의 중요성과 역할

김창근(Chang Geun Kim),박주근(Jookeun Park),채균식(Kyun Shik Chae),방건웅(Gun Woong Bahng) 대한인간공학회 2009 대한인간공학회 학술대회논문집 Vol.2009 No.5

참조표준은 측정표준 및 성문표준과 함께 국가표준기본법에 명시되어 있을 정도로 중요한 표준분야이다. 참조표준은 엄밀한 평가 과정을 거쳐 그 신뢰성이 보장된 수치 데이터를 의미한다. 데이터의 신뢰성을 보장하기 위해서는 데이터의 평가기준 수립, 평가기준에 의거한 데이터 평가 과정을 거쳐야 한다. 이러한 체계를 갖추기 위하여 국가참조표준센터가 2006년에 설립되었으며 2009년 현재 12개의 데이터센터가 지정되어 각 담당 분야별로 참조표준을 확립하기 위한 작업을 수행하고 있다. 본 논문에서는 참조표준의 개념과 참조표준체계, 그리고 활용에 대해 간략하게 기술하였다.

충돌해석 시 동적인장물성 불확도의 영향 평가

정세환(Sehwan Jeong),허훈(Hoon Huh),최민국(Min Kuk Choi),채균식(Kyun Shik Chae),김창근(Chang-Geun Kim) 한국자동차공학회 2011 한국자동차공학회 학술대회 및 전시회 Vol.2011 No.11

This research is concerned with the standard uncertainties in the tensile properties of auto-body steel considering strain rate effects and effects of uncertainties of tensile properties on crash analyses. A procedure to obtain plastic true stress data and analytic uncertainty model are established. Uncertainty sources in the high-speed tensile test are summarized. Standard uncertainties in measuring input quantities such as load, length, thickness, and width of the specimens are calculated, as are their associated sensitivity coefficients. Uncertainty induced by the FFT smoothing process used to reduce unnecessary signal in acquired data is also considered. Image analysis using a high-speed camera is performed in order to measure the length of the specimen during the high-speed tensile test. Combined standard uncertainty is then evaluated for the true stress data of an auto-body steel sheet at intermediate strain rates. Crash analysis of a square tube is performed with measured true stress data considering standard uncertainties. In the analyses, maximum and minimum values of true stress data in the range of expanded uncertainty are applied into the analyses. Finally, effects of the uncertainties on the crash analyses are quantitatively evaluated.

금속소재의 참조표준 평가기준 개발

남승훈(Seung Hoon Nahm),이윤희(Yun-Hee Lee),백운봉(Un Bong Baek),채균식(Kyun Shik Chae),방건웅(Gun Woong Bahng) 대한기계학회 2006 대한기계학회 춘추학술대회 Vol.2006 No.3

Reference standards are usable data to be used repeatedly, widely and continuously in all fields. They are authorized by analyzing scientifically and estimating the accuracy and reliability of measurement data and information. They are physical-chemical constants, authorized properties, authorized scientific- technological statistics, etc. Reference standards are national infra in connection with almost industry field as well as basic scientific technique fields. To develope reference standards evaluation system for tensile properties of metallic materials, evaluation procedure and criterion of tensile properties of metallic materials were described briefly in this study.

자동차용 강판 동적인장물성 측정에서의 표준불확도평가

정세환(Sehwan Jeong),허훈(Hoon Huh),방건웅(Gun Woong Bahng),김창근(Chang Geun Kim),채균식(Kyun Shik Chae) 한국자동차공학회 2011 한국자동차공학회 부문종합 학술대회 Vol.2011 No.5

The crashworthiness of auto?body structures is one of the important issues in the automotive industry. The crash analysis with finite element methods has been conducted in order to evaluate the crashworthiness of auto?body structures. In the car crash, auto?body structures undergo deformation with a wide range of strain rate from 0.001/sec to 500/sec. Since the material properties of steel sheets depend on the rate of deformation, in order to ensure the impact characteristics of auto?body structures accurately, the dynamic behavior of sheet metals must be examined and applied to the finite element model appropriately. This research is concerned with standard uncertainty evaluation of tensile properties of auto-body steel sheets in wide range of strain rate from 0.001/sec to 100/sec. Stress-strain relations of an auto-body steel sheet were obtained with quasistatic and high speed tensile tests. Uncertainty components in both testing methods are summarized and standard uncertainties of each input quantities are evaluated. An analytic model is established in order to calculate combined standard uncertainty of the measurand. The measurand is true stress with respect to true strain and the input quantities are load and displacement data during the tensile test and initial dimensions of specimen such as thickness, width and length. Uncertainties which come from signal processing and deviation of measured values in repetitive tests are also considered.

개선된 자동차용 강판 동적인장물성 측정에서의 표준불확도평가

최민국(Min Kuk Choi),정세환(Sehwan Jeong),허훈(Hoon Huh),김창근(Chang Geun Kim),채균식(Kyun Shik Chae) 한국자동차공학회 2013 한국자동차공학회 부문종합 학술대회 Vol.2013 No.5

Evaluation of the crashworthiness is one of the important issues in the automotive industry. In order to evaluate the crashworthiness of auto-body structure, finite element methods has been conducted for crash analysis. Generally, strain rates distribution of auto-body structure in the car crash is ranging from 0.001/s to 500/s. Since the material properties of steel sheets depend on the strain rates, the dynamic behavior of sheet metals must be examined and applied to the finite element model appropriately. This paper is concerned with the evaluation of standard uncertainty of modified measurement of high speed tensile properties of auto-body steel sheets. Obtaining procedure of the true stress?true strain data at intermediate strain rates is properly designed for the experiment and data acquisition compared with previous procedure. Standard uncertainty of the true stress is evaluated considering sources of uncertainties of input quantities and their associated sensitivity coefficients. A combined standard uncertainty is evaluated from not only the uncertainties of the input quantities but also the influence factor for the true stress. The results show that the standard uncertainty evaluation procedure has been successfully applied to high speed tensile properties.