NHPP에 기초한 소프트웨어 신뢰도 모형에 대한 베이지안 추론에 관한 연구

이상식,김희철,송영재,Lee, Sang-Sik,Kim, Hui-Cheol,Song, Yeong-Jae 한국정보처리학회 2002 정보처리학회논문지D Vol.9 No.3

본 논문에서는 비동질 포아송 과정에 기초한 소프트웨어 오류 현상에 대한 신뢰도 모형을 고려하고 사전정보를 이용한 베이지안 추론을 시행하였다. 고장 패턴은 NHPP에 대한 강도함수와 평균값 함수로서 나타낼 수 있다. 따라서 본 논문에서는 기존의 모형인 Goel이 제시한 모형과 신뢰성 분포로 많이 사용되는 와이블 분포의 특수형태인 레일리분포와 라플라스 분포를 이용한 모형을 제시하여 베이지안 추론을 시행하고 또, 효율적 모형을 위한 모형선택으로서 편차자승합을 이용하여 비교하였다. 모수의 추정을 위해서 마코브체인 몬테카를로 기법중에 하나인 깁스샘플링을 이용한 근사추정 기법이 사용되었다. 수치적인 예에서는 실측자료인 NTDS 자료를 이용하여 모수 및 신뢰도를 추정하였고 편차자승합을 이용한 모형비교의 결과를 나열하였다. Software reliability growth models are used in testing stages of software development to model the error content and time intervals between software failures. This paper presents a stochastic model for the software failure phenomenon based on a nonhomogeneous Poisson process(NHPP) and performs Bayesian inference using prior information. The failure process is analyzed to develop a suitable mean value function for the NHPP ; expressions are given for several performance measure. Actual software failure data are compared with several model on the constant reflecting the quality of testing. The performance measures and parametric inferences of the suggested models using Rayleigh distribution and Laplace distribution are discussed. The results of the suggested models are applied to real software failure data and compared with Goel model. Tools of parameter point inference and 95% credible intereval was used method of Gibbs sampling. In this paper, model selection using the sum of the squared errors was employed. The numerical example by NTDS data was illustrated.

국내 포털사이트 음원서비스 취약점분석 및 대응방안 제안

이상식,최동현,원동호,김승주,Lee, Sang-Sik,Choi, Dong-Hyun,Won, Dong-Ho,Kim, Seung-Joo 한국정보처리학회 2009 정보처리학회논문지 C : 정보통신,정보보안 Vol.16 No.6

현재 국내 음악산업은 음반시장에서 디지털음악시장으로 중심이 이동하고 있으며, 대부분의 대형 포털사이트에서 디지털 음원서비스를 제공하고 있는 추세이다. 본 논문에서는 국내 포털사이트(도시락, 싸이월드, 네이버)에서 제공하고 있는 음원서비스프로세스를 살펴보고 취약점을 분석한다. 또한 분석된 취약점을 바탕으로 실제 공격을 수행하여 음원서비스의 문제점을 보여준다. 마지막으로 본 논문에서는 이러한 취약점을 해결할 수 있는 기술적인 대응방안을 제안함으로써 기업과 저작권자의 이익을 보호하고자 한다. Nowadays, the music industry is moving from analog to digital. Most of the big portal sites provide commercial online music streaming services according to the tendency. In this paper, we analyze the security of the Korean commercial online music streaming services which are provide by the Korea's major portal sites(Dosirak, Cyworld, and Naver). Moreover, we show attacks on commercial online music streaming services that lead to an infringement of copyright and propose technical countermeasures for online commercial music streaming services, the contributions of the present work are that the measures protect the copyright of the music.

비동질적 포아송과정을 사용한 소프트웨어 신뢰 성장모형에 대한 베이지안 신뢰성 분석에 관한 연구

이상식,김희철,송영재,Lee, Sang-Sik,Kim, Hee-Cheul,Kim, Yong-Jae 한국정보처리학회 2003 정보처리학회논문지D Vol.10 No.5

본 논문에서는 비동질 포아송 과정(NHPP)에 기초한 소프트웨어 에러 현상에 대한 신뢰도 모형을 고려하고 사전정보(Prior information)를 이용한 베이지안 추론을 시행하였다. 고장 패턴은 NHPP에 대한 강도함수와 평균값 함수로서 나타낼 수 있다. 따라서 본 논문에서는 대수형 포아송 실행시간 모형(Logarithmic Poisson model), Crow 모형 그리고 Rayleigh 모형에 대하여 베이지안 모수 추정방법을 적용하였다. 효율적 모형을 위하여 이들 모형에 관한 모형선택을 편차자승합(SSE)의 합을 이용하여 시행하였고 모수의 추정을 위해서 마코브체인 몬테카를로(MCMC) 기법중에 하나인 깁스샘플링(Gibbs sampling)과 메트로폴리스 알고리즘을 이용한 근사추정 기법이 사용되었다. 수치적인 예에서는 Musa의 T1 자료를 이용하여 모수 및 신뢰도를 추정한 수치 결과론 나열하였다. This paper presents a stochastic model for the software failure phenomenon based on a nonhomogeneous Poisson process (NHPP) and performs Bayesian inference using prior information. The failure process is analyzed to develop a suitable mean value function for the NHPP; expressions are given for several performance measure. The parametric inferences of the model using Logarithmic Poisson model, Crow model and Rayleigh model is discussed. Bayesian computation and model selection using the sum of squared errors. The numerical results of this models are applied to real software failure data. Tools of parameter inference was used method of Gibbs sampling and Metropolis algorithm. The numerical example by T1 data (Musa) was illustrated.

폐천의 습지 활용에 대한 레크리에이션 및 심미적 가치평가

이상식,김형수,정상만,Lee. Sang-Sik,Kim. Hung-Soo,Jeong. Sang-Man 한국방재학회 2002 한국방재학회논문집 Vol.2 No.1

본 연구에서는 통상 농경지 및 택지로 이용하고 있는 폐천의 경제적 가치에 대해 연구하였다. 즉, 폐천을 농경지로 활용하였을 경우와 습지나 위락단지로 활용하였을 경우에 대한 경제적 가치를 평가 비교하고자 하였다. 연구 대상유역은 한강의 제1지류인 곡릉천의 하류를 선정하였다. 농경지로 활용하였을 경우는 농림통계연보(2000)를 이용하여 그 가치를 산정하였고, 자연습지나 위락단지로 활용하였을 경우에 대해서는 설문조사를 통하여 그 가치를 평가하였다. 즉, 습지나 위락단지의 레크리에이션 가치는 설문조사 결과를 여행자비용법에 의해서 산정하였고, 심미적 가치는 선진국의 선례를 토대로 설문조사를 작성한 후 그 결과를 이용하여 가치를 평가하였다. 분석 결과 폐천을 농경지로 활용하였을 경우, 연간균등편익은 7.05 백만원으로 산정되었고, 습지와 레크리에이션 목적으로 활용하였을 경우에 대해서는 각각의 연간균등편익이 1931.4 백만원과 6284.86 백만원으로 산정되었다. 또한, 심미적 가치는 1년에 14만원으로 산정되었다. 따라서 폐천부지를 농경지로 활용할 경우 보다 습지나 위락시설로 활용할 경우가 훨씬 더 큰 가치를 보이고 있다. The cut river is widely used for the agricultural and housing purposes in Korea and this study is to evaluate the economic value of the cut river. Say, the study is to evaluate and compare the economic values for the cases of which the cut river can be used as the agricultural or housing site and a wetland or recreational site. The study area is the downstream part of Kok-Neung stream which is a main tributary of Han River. For the case of assuming the cut river is used as the agricultural purpose, the value is estimated from the Agricultural & Forestry Statistical Yearbook 2000. For the case of assuming the cut river is used as a wetland or recreational site, the value for a wetland or recreation is estimated by the enquete using questionnaire. That is to say, the results of enquete is used for the estimation of a recreational value by the Travel Cost Method (TCM) and the aesthetical value is estimated by the enquete based on the presumed value in USA. As a results, for the case of which the cut river is used as an agricultural purpose, the equal-payment-series is estimated as 7.06 million won. For wetland purpose, the series is estimated as 1931.40 million won and for the recreational purpose, the series is as 6284.86 million won. The aesthetical value is estimated as 140 thousand won per annum. Therefore, the wetland or recreational use of the cut river is more valuable than agricultural or housing purpose.

방향성 비선형 필터에 의한 화상의 잡음 제거

이상식(SANG SIK LEE),이태홍(TAE HONG LEE) 한국통신학회 1988 한국통신학회 학술대회논문집 Vol.1988 No.11

숙종대 保社功臣의 錄勳 과정과 사회적 關係網 분석

이상식(Lee Sang Sik) 한국사연구회 2011 한국사연구 Vol.155 No.-

The ensuring the legitimacy of the royal family and the stability of the throne was the core agenda in the early King Sukjong[肅宗] times. Ensuring legitimacy of royal family was resolved through the rites dispute of 1674[甲寅禮訟], the stability of the throne relying on Heo Jeok[許積], the Royal family[宗戚] the Relatives of queens[外戚] was maintained. Sam-bok[三福] and Faction Southerners[南人] were one of the axis powers in the early King Sukjong, But they were removed by Kim Seok-ju[金錫?] on the Regime change in the year 1680. King Sukjong, in spite of the opposition. was actively involved in the process of the Merit Subject[功臣] to build the guard forces. Relying on this, he realized his will to power. This article identifies what has been the formation of the power structure. whether contemporary awareness of how a meritorious retainer look in the early Sukjong through the process of the Merit Subject in 1680 year[保社功臣]. For social network analysis. I will explore the political relations and influence of the meritorious retainer. And from the prosecution three times in the year 1682[壬戌三告變], to the regime exchange in 1689[已巳換局], We are find a clue to understand a political structure and the operation The first course of the Merit Subject appointed led by King Sukjong was conducted quickly without a little opposition. It was an awkward implementation why King Sukjong prevented the conspiracy treat form sparking political power struggle between the political clique[朋黨]. However Lee Won-sung[李元成] having accused plotted, King Sukjong and the Relatives of queens was opposed to the political clique whether adding the record of the Merit Subject right. The authority of the Merit Subject and the Meaning of the regime exchange in 1680 was halved by the conflict between them. And the officiary promotion of Lee Sa-myung[李師命] and Sin Beom-hwa[申範華] was a watershed in the prosecution three times in the year 1682. Meanwhile, the personal relationships of the Merit Subject was connected by the adjutant soldiers or the relatives. They can be divided into two, Gim Man-gi[金萬基] group and Gim Seok-ju[金錫?]. Gim Man-si group. Yi Ip-sin[李立身], Nam Du-buk[南斗北] and soldiers entered into a relationship with Sam-bok[三福], Heo-gyeon[許堅]. Sin Beom-hwa[申範華] and Faction Southerners[南人]. Their role in the process of the regime exchange[換局] is the following. The first Merit Subject’s[正勳功臣] role was primarily spying activities. These were the person who were parasitic on the periphery of power rather than the core of power. On the other hand. The second Merit Subject’s[追錄功臣] role was limited to the planning and supporting rather than the direct action. Their officiary activities is the following. The first Merit Subject[正勳功臣]. most of them were appointed in the province and a soldier. The second Merit Subject[追錄功臣] were appointed in the special official by meritorious deed[蔭職] or the retired official[散職]. They were closely related to Sam-bok brother and Heo Jeok. After the regime exchange in 1680[庚申換局], they had been blocked by the political clique including the censorate[臺諫] on entering the officiary and the central government. On the other hand. the first Merit Subject undergone impeachment by the corruption and the lack of qualifications. the second Merit Subject were undergone impeachment by Justification. The potential conflict between the Merit Subject and the political clique sparked the prosecution three times in the year 1682. For the conflict and division between the Merit Subject. their political influence has been shrinking rapidly.

논문 : 노외기계시스템공학 ; 3점 히치 장착형 암식 작업기의 전자유압특성 분석

이상식 ( Sang Sik Lee ),박원엽 ( Won Yeop Park ) 한국농업기계학회 2011 바이오시스템공학 Vol.36 No.5

Arm-type implements of tractor are mainly utilized for the slope land operation. The proposed hydraulic system was implemented to arm-type implements of tractor. An experiment was conducted to evaluate response characteristics of the designed arm-type implement control system attached by three-point hitch of tractor at various conditions, such as engine speed, pumping rate and cylinder input flow. Effects of the valve response time didn`t affect engine speed. The flow rate of pump and cylinder changed to the pressure loss. Also, the pressure loss was within 2 MPa and the response characteristic was sufficient enough to use as the arm-type implement system.

Cog type과 Mono type 봉합사의 인장강도에 관한 기초 실험 연구

이상식(Sang-Sik Lee),신운섭(Un-Seop Shin),박병곤(Byung-Gon Park),류옥수(0k-Su Ryu) 대한전기학회 2016 대한전기학회 학술대회 논문집 Vol.2016 No.2

해양심층수 타라소테라피 적용에 따른 체간 관절가동범위와 최대근력의 변화

이상식(Sang-Sik Lee),김준태(Jun-Tae Kim),신운섭(Woon-Seob Shin),김남익(Nam-Ik Kim),류옥수(Ok-Su Ryu),장지훈(Jee-Hun Jang) 한국발육발달학회 2017 한국발육발달학회지 Vol.25 No.3

The purpose of this study was to evaluate the effects of deep sea water thalassotherapy(TT) program for trunk range of motion(ROM) and maximal strength(MS). Subjects were 40 male university students, and assigned randomly into 4 groups: ground exercise group(GEX, n=10), immersion in the water group(IMW, n=10), water exercise group(WEX, n=10), and deep sea water exercise group(DEX, n=10). Hydrotherapy(HT) and TT program was consisted of 8 exercises for cervical joint(CJ), 11 exercises for lumbar joint(LJ). Time was 16 min. for CJ, and 21 min. for LJ. Flexion and extension ROM, and flexion MS and extension MS in CJ and LJ was measured repeatedly before and after the program application. As a result, all variables were significantly increased after TT in DEX(p<.05). In WEX, flexion ROM in CJ, extension ROM in LJ, flexion and extension MS in LJ was significantly increased after HT(p<.05). No significant difference was shown in GEX and IMW. In conclusion, it is suggested that TT program in this study could be introduced as a floating exercise for trunk flexibility and muscular strength in deep sea water spa resort.

비만치료기 개발에 따른 저준위레이저에 관한 연구

이상식(Sang-sik Lee),김준태(Jun-tae Kim),정진형(Jin-hyoung Jeong),김남선(Nam-Sun Kim) 한국정보전자통신기술학회 2016 한국정보전자통신기술학회논문지 Vol.9 No.1

경제성장과 더불어 고령화 사회로 진입하여 ‘아름답고 건강하게 사는 욕구’와, ‘항 노화’에 대한 관심이 증진됨에 따라 미학 산업이 유망사업으로 부각되어 스킨케어 시장을 크게 증가시켰다. 하지만 병원이나 전문 관리업체의 관리를 받기위해서는 시간적, 공간적, 비용적 제약이 발생하여, 이를 해결하기 위해 많은 업체들이 홈 케어 방면으로 접근하기 시작했다. 세계적인 추세로 개인용 스킨케어 시장이 활성화 되었으며, 국내는 경기침체로 인한 저비용, 개인용 시장이 활성화 되었다. 우리는 이러한 점을 보완하기 위하여 가정용 스킨케어 장치를 개발하기 위해 본 실험을 실시하였다. 본 논문에서는 개인용 스킨케어 제품을 만들기 위해 저준위 레이저를 개발하고 이를 피부 미용적으로 접목시키기 위해 노력하였다. 피부에 저준위 레이저를 사용함으로써 모공을 확장시켜 피부의 진피층까지 해당 앰플을 침투시키는데 목적을 두고 실험하였으며, 의료용 저준위 레이저와의 비교를 통하여 안정성 및 성능의 효율성 유무를 판단하고 상용화 할 수 있도록 노력하였다. And by entering into an aging society with economic growth "beautiful and healthy desire to live ", aesthetics industry as promote interest in "Anti-aging "is emerging as a promising business increased significantly the skin care market. However, the management of the hospital or the temporal order to receive professional care providers, spatial, and cost constraints caused many companies to solve this problem began to approach the Home Care Area. Global trends in personal skin care market has been activated, the domestic has been activated at low cost, private market due to the recession. We have performed this test in order to develop a skin care device for home in order to compensate for this point.In this paper, we develop a low-level laser to create a personal skin care products and sought to incorporate them into the skin cosmetic.Expand the pores by using the low-level laser to the skin by to the dermal layer of the skin was penetrated aim experiment the ampoule, and by a comparison of the medical low-level laser reliability and determine the effectiveness or absence of the performance and efforts to commercialize.