인증기관 구성 및 운영정책 요구사항 분석

김영덕,정재수,최용락 대전대학교 산업기술연구소 1999 산업기술연구소 論文集 Vol.10 No.1

This study purposes to analyze the configuration of CAs(Certification Authorities) and the operating policy of CAs for cross-trusted authentication services. The CA is an authority trusted by one or more users to create and assign certificates being used to user authentication in the network. In this paper, each country's law related to Electronic Commerce and the requirement of PKI(Public Key Infrastructure) components are analyzed, and the guideline to organize CA mechanism in the domestic is mentioned

인증서의 상호인증을 위한 모델 체크리스트 분석

김영덕,신동명,최용락 대전대학교 산업기술연구소 1999 산업기술연구소 論文集 Vol.10 No.2

The Certification Authority in each country is briskly in progress to get the reliability of Electronic Commerce. One Certification Authority can not authenticate the reliability of Electronic Commerce spreading itself to the world rapidly. Therefore, Each country is constructing the base of Electronic Commerce Authority System and trying to provide cross connection with compatibility through the Cross-Authentication. This paper analysed the requirements of Cross-Authentication Mechanism on researching internationally and proposed the check-list of Cross-Authentication Model. The paper could be a guidance to organize domestic Cross-Authentication System Models.

DEVS 형식론을 이용한 RAID 시스템의 시뮬레이션

성영락 국민대학교 생산기술연구소 2002 공학기술논문집 Vol.25 No.-

In this paper, a RAID level 5 system is modeled by using the DEVS formalism. The system consists of one MPU and two PCI buses. For accurate evaluation of RAID system performance, modeling of the PCI bus and MPU are crucial. In the PCI bus model, start and end of message transfer are precisely modeled to measure the bus transfer time. The MPU model specifies the RAID software algorithm as well as the hardware architecture. Several input patterns are applied for verifying the modeling results.

시간적인 지역성을 이용한 실시간 태스크들의 전력을 고려한 스케줄링

성영락 국민대학교 생산기술연구소 2004 공학기술논문집 Vol.27 No.-

Many real-time tasks have a limited number of operation states which changes with temporal continuity. This paper proposes a novel dynamic voltage scaling algorithm, called TLDVS, for real-time tasks in order to exploit the temporal locality. TLDVS achieves significant energy savings while still preserving timeliness guarantees made by real-time scheduling. Time budgets for each task are divided into two parts. Then the task executes at the lowest attainable frequency/voltage level in the first part. If the task does not complete until the end of the first part, then the scheduler is invoked and increases the processor frequency and voltage to complete the remaining computation load with the remaining time budgets. Simulation results show that TLDVS provides up to 25% of additional energy savings.

온라인 게임을 위한 이 단계 주 메모리 데이터베이스 시스템

성영락 국민대학교 생산기술연구소 2003 공학기술논문집 Vol.26 No.-

In this paper, a main memory database management system for online games is proposed. An online game system is composed of several game servers and a single database server. Since all database operations are concentrated to the database server, the database server is a major bottleneck of online game systems. A main memory database management system employs RAM rather than hard disks as its storage media. Accordingly, the execution speed can be drastically enhanced. The proposed main memory database management system is composed of two layers: the game server main memory database management system and the database server main memory database management system. By using the proposed scheme, the communication cost between the database server and game servers as well as the disk I/O cost of the database server can be substantially reduced.

분산 어플리케이션의 정보보호 서비스를 위한 CAPI 설계 모델

이상기,김영덕,최용락 대전대학교 산업기술연구소 1998 산업기술연구소 論文集 Vol.9 No.2

Until recently, the integration of cryptographic functionality into application program has required that developers tightly couple the application to the cryptographic module. This approach forces each new combination of application and cryptography to be treated as a distinct development effort, and does not provide the modularity and maintainability. An approach that can provide flexibility and cost saving is the use of a standardized CAPI(Cryptographic Application Prigram Interface) suite. This Paper analyze the CAPI for the development of various types of security application programs in distributed environment. The analysis of CAPI are considered with the respect of 7 criteria items such as algorithm independence, application independence, cryptomodule independence, the degree of cryptographic awareness, modular design and auxiliary services, safe programming and security perimeter. In this paper, we suggested the basis of utilization to be selected for develope the cryptographic modules in distributed applications.

아동기 가정 내 스트레스가 공동의존성에 미치는 영향 및 공동의존성과 정신병리와의 관련성

곽운환,손지욱,한규희,박철수,김장락,김붕년,김봉조,강여화,하형래 대한생물치료정신의학회 2003 생물치료정신의학 Vol.9 No.1

연구목적: 본 연구는 공동의존성에 영향을 미치는 아동기 가정내 스트레스 요인과 공동의존성과 다른 병리와의 연관성을 규명하고자 하였다. 더불어 특정한 질환에서의 공동의존성의 평가가 가지는 의의를 탐색해 보고자 하였다. 방 법: 연구 대상은 정상 일반인 남성집단 88명과 알코올리즘 남성 집단 76명으로 구성되어 있다. 평가도구는 본 저자가 직접 작성한 '아동기 가정내 스트레스 요인 측정용 설문'과 공동의존 척도(RPS), 간이증상 진단검사(SCL-90-R)를 사용하였다. 통계적 분석은 Mann-Whitmey test, Kruskall- Wallis test, Multiple linear regression analysis, Spearman correlation analysis를 이용하였다. 결 과: 1) 정상 일반인 군과 알코올리즘 군의 공동의존성 평균값은 각각 49.12점(표준편차=15.41)과 88.31점(표준편차=17.48)이었다. 2) 정상 일반인 군에서는 '아동기 부모 사별'(p<0.01) '부모의 알코올리즘'(p<0.01) '부모의 상습적 구타'(p<0.01)의 3가지 요인에서, 알코올리즘 군에서는 '어린시절 부모 사별'(p<0.01) '부모의 알코올리즘'(p<0.01) '부모의 상습적 구타'(p<0.01) '부도의 도박'(p<0.01) '사회 병질자 부모의 존재'(p<0.05)의 5가지 요인에서 스트레스 유무에 따라 공동의존성에 유의한 차이를 보였다. 3) 두 집단 동시에 SCR-90-R의 8개 소척도 중 '대인관계 예민성'이 공동의존성과 가장 높은 연관성(rs>0.06, p<0.01)을 보였다. 이외에도 '우울증' '불안증'등이 두 집단 모두에서 통계적으로 유의한 연관성을 보였다. 결 론: 본 연구는 부모의 알코올리즘뿐만 아니라 여러 가정 내 스트레스 요인이 공동의존성의 발생에 영향을 미칠 수 있음과 공동의존성이 높은 집단이 다른 정신과 질환을 동반할 가능성이 높음을 증명한다고 할 수 있다. Objectives : The aim of this study was to examine the relationships of codependency with family stressors in childhood and psychopathology. Methods : Subjects were a group of 88 normal adult males and a group of 76 alcoholic males. The degree of codependency was assessed with the Korean version of Recovery Potential Survey(RPS). All subjects filled out questionnaires regarding demographic information and family stressors. The psychopathology was measured by self-administred questionnaires using Symptom Check List-90-Revision(SCL-90-R). Results : 1) There were no significant differences in codependency levels by sociodemographic characteristics in two groups, but obvious difference in mean of codependency scores(normal group : 49.12±15.41, alcoholism group : 88.31±17.48). 2) There were significant differences in codependency levels between the presence and absence of parental physical abuse, parental death, and parental alcoholism(p<0.01) in both groups. 3) Among family stressors, parental physical abuse had the largest contribution to codependency level in multiple linear regression. 4) There were significant correlations between the codependency levels and the scores of SCL-90-R's subscales of interpersonal sensitivity, depression, and anxiety in both groups. Conclusion : The codependency levels were related to some family stressors such as parental physical abuse, parental death, and parental alcoholism and the high-level codependency was correlated with higher level of psychopathology in both normal and alcoholism group. These results suggested that various family stressors, as well as parental alcoholism may be predictors of codependency, and codependency also may be a predictor of other psychiatric disorders.

웨이브렛 변환을 이용한 배전계통의 전력품질 외란 검출에 관한 연구

孫永洛(Yeong-Rak Son),李和錫(Hwa-Seok Lee),文景俊(Kyeong-Jun Mun),朴俊灝(June Ho Park),尹在暎(Jae-Young Yoon),金鍾律(Jong-Yul Kim),김슬기(Seul-Ki Kim) 대한전기학회 2005 전기학회논문지A Vol.54 No.7

NO96타입 LNG 방열시스템 Divinycell의 극저온 압축 강도 평가

최영락(Yeong-Rak Choe),김정현(Jeong-Hyeon Kim),김종민(Jong-Min Kim),박성균(Sungkyun Park),박강현(Kang Hyun Park),이재명(Jae-Myung Lee) 한국해양공학회 2016 韓國海洋工學會誌 Vol.30 No.5

Divinycell, which functions as both insulation and a supporting structure, is generally applied in the NO96-type liquefied natural gas (LNG) insulation system. Polymer-material-based Divinycell, which has a high strength and low weight, has been widely used in the offshore, transportation, wind power generation, and civil engineering fields. In particular, this type of material receives attention as an insulation material because its thermal conductivity can be lowered depending on the ambient temperature. However, it is difficult to obtain research results for Divinycell, even though the component materials of the NO96-type LNG cargo containment system, such as 36% nickel steel (invar steel), plywood, perlite, and glass wool, have been extensively studied and reported. In the present study, temperature and strain-rate dependent compressive tests on Divinycell were performed. Both the quantitative experimental data and elastic recovery are discussed. Finally, the mechanical characteristics of Divinycell were compared to the results of polyurethane foam insulation material.

하이퍼큐브 환경에서의 DEVS 모델의 병렬 시뮬레이션을 위한 매핑

성영락(Yeong Rak Seong),김탁곤(Tag Gon Kim),박규호(Kyu Ho Park) 한국정보과학회 1995 정보과학회논문지 : 시스템 및 이론 Vol.22 No.10

DEVS(Discrete Event Systems SpecificatIon) 형식론은 이산사건 시스템을 계층적으로 모듈화된 형태로 기술한다. DEVS에서 상태전이는 스케쥴링에 의한 내부사건과 불규칙적으로 도착하는 외부 사건에 의해서 이루어진다. P-DEVSim++는 DEVS 모델들을 위한 병렬 분산 시뮬레이션 환경이다. P-DEVSim++에서는 DEVS의 외부사건 외에 내부사건이 병렬처리 된다. 본 논문에서는 P-DEVSim++을 하이퍼큐브 멀티컴퓨터 환경에서 다중통신 없이 수행할 때 그 병렬성을 이용하기 위한 DEVS 모델의 매핑에 대해서 다룬다. 동시에 발생되는 외부사건에 대해서는 동기화를 위한 오버헤드를 줄이기 위해서 태스크 그래프를 이항트리로 변환하였다. 또 여러 내부사건이 동시에 발생되고 각 내부사건이 여러 외부사건을 야기할 경우에는 전체 하이퍼큐브를 서브큐브들의 집합으로 나누어서 하나의 내부사건과 그에 관련된 외부사건들이 같은 서브큐브에서 처리되도록 하였다. 실험을 통하여 제안된 알고리즘의 성능을 측정하였다. 실험 결과, 파라미터들이 바뀜에 따라, 제안된 매핑 알고리즘은 여러 다양한 매핑을 구하였다. 또, 그 구해진 매핑을 이용하여 계층적으로 모듈화된 이산사건 모델의 분산 시뮬레이션에서의 병렬성을 얻을 수 있었다. The DEVS(Discrete Event System Specification) formalism specifies discrete event systems in a modular, hierarchical manner. Within the formalism, state transition is achieved by scheduled internal events and randomly arrived external events. P-DEVSim++ is a parallel, distributed simulation environment for DEVS models In P-DEVSim++, internal events as well as external events are processed in parallel. This paper addresses mapping of DEVS models to utilize the parallelism of P-DEVSim++ in a hypercube multicomputer environment without multicasting, For simultaneous external events processing, task graphs are transformed into binomial trees to reduce synchronization overhead. Also, when multiple internal events occur simultaneously and each internal event is associated with multiple external events, a hypercube is partitioned into a set of subcubes so that an internal event and the associated external events can be processed in the same subcube. The performance of our algorithm is measured through experimentation The result shows that the proposed mapping algorithm generates diverse mappings against various combinations of system parameters. With the generated mapping, the significant parallelism of distributed simulation of hierarchical, modular discrete event models is achieved.