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.

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.

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.

골반골절 환자의 골절위치와 출혈량간의 상관관계 분석을 통한 대량수혈 필요에 대한 간단한 예측도구 개발: 골반골 출혈 지수

이상식 ( Sang Sik Lee ),배병관 ( Byung Kwan Bae ),한상균 ( Sang Kyoon Han ),박성욱 ( Sung Wook Park ),류지호 ( Ji Ho Ryu ),정진우 ( Jin Woo Jeong ),염석란 ( Seok Ran Yeom ) 대한외상학회 2012 대한외상학회지 Vol.25 No.4

Purpose: Hypovolemic shock is the leading cause of death in multiple trauma patients with pelvic bone fracures. The purpose of this study was to develop a simple prediction method for injury severity and amount of hemorrhage via an analysis of the correlation between the site of pelvic bone fracture and the amount of transfusion and to verify the usefulness of the such a simple scoring system. Methods: We analyzed retrospectively the medical records and radiologic examination of 102 patients who had been diagnosed as having a pelvic bone fracture and who had visited the Emergency Department between January 2007 and December 2011. Fracture sites in the pelvis were confirmed and re-classified anatomically as pubis, ilium or sacrum. A multiple linear regression analysis was performed on the amount of transfusion, and a simplified scoring system was developed. The predictive value of the amount of transfusion for the scoring system as verified by using the receiver operating characteristics (ROC). The area under the curve of the ROC was compared with the injury severity score (ISS). Results: From among the 102 patients, 97 patients (M:F=68:29, mean age=46.7±16.6 years) were enrolled for analysis. The average ISS of the patients was 16.2±7.9, and the average amount of packed RBC transfusion for 24 hr was 3.9±4.6 units. The regression equation resulting from the multiple linear regression analysis was ``packed RBC units=1.40×(sacrum fracture)+1.72×(pubis fracture)+1.67×(ilium fracture)+0.36`` and was found to be suitable (p=0.005). We simplified the regression equation to ``Pelvic Bleeding Score=sacrum+pubis +ilium``. Each fractured site was scored as 0(no fracture) point, 1(right or left) point, or 2(both) points. Sacrum had only 0 or 1 point. The score ranged from 0 to 5. The area under the curve (AUC) of the ROC was 0.718 (95% CI: 0.588-0.848, p=0.009). For an upper Pelvis Bleeding Score of 3 points, the sensitivity of the prediction for a massive transfusion was 71.4%, and the specificity was 69.9%. Conclusion: We developed a simplified scoring system for the anatomical fracture sites in the pelvis to predict the requirement for a transfusion (Pelvis Bleeding Score (PBS)). The PBS, compared with the ISS, is considered a useful predictor of the need for a transfusion during initial management. (J Trauma Inj 2012;25:139-144)

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.

수소생산을 위한 메탄 부분산화용 코발트와 니켈촉매의 반응특성 연구

이상식 ( Sang Sik Lee ),홍주환 ( Ju Hwan Hong ),하호정 ( Ho Jung Ha ),김병관 ( Byung Kwan Kim ),한종대 ( Jong Dae Han ) 한국화학공학회 2010 Korean Chemical Engineering Research(HWAHAK KONGHA Vol.48 No.6

Co and Ni catalysts supported on Al2O3 for partial oxidation of methane producing hydrogen were synthesized using impregnation to incipient wetness. The activities of these catalysts for the partial oxidation of methane was investigated at 1atm and CH4/O2=2.0 in the temperature range of 450~650˚C. The reaction activity of Ni/Al2O3 and Co/Al2O3 catalysts with different loading was investigated. And the beneficial effects of Ni addition to Co/Al2O3 and the promotional effects of Ce and La addition to Ni/Al2O3 and Co/Al2O3 were investigated. These catalysts were characterized by XRD and SEM/EDX. Comparing catalyst loadings, 10 wt% Co and 10 wt% Ni were found to be optimal at the experimental conditions. The 10 wt% Ni/Al2O3 and 10 wt% Co/Al2O3 catalysts in partial oxidation of methane showed CH4 conversions and CO selectivity close to the thermodynamic equilibrium levels, but showed lower H2 selectivity than equilibrium level. The addition of Ni to Co/Al2O3 exhibited higher H2 selectivity but beneficial effect was not observed in the CH4 conversion. Addition of Ce to Co/Al2O3 and addition of La to Ni/Al2O3 improved the CH4 conversion level and H2 selectivity.

수직상승형 고소작업차의 개발을 위한 구조해석

이상식(Sang-Sik Lee),김준태(Jun-Tae Kim),박원엽(Won-Yeop Park) 한국정보전자통신기술학회 2017 한국정보전자통신기술학회논문지 Vol.10 No.3

본 연구는 과수원에서 높은 곳에서의 작업을 진행함에 있어 안정적인 고소작업 기계차의 제작을 위하여 진행하였다. 과수원의 경우 비포장도로 및 경사진 지면이 많아 고소작업 기계차가 과수원에서 작업함에 있어 전복이 되거나 안전성에 관하여 문제가 되고 있는 부분을 해결하기 위함이다. 보다 안정적인 작업을 위하여 Auto leveling system을 설계 하였고 구조해석을 하는 도중 우리가 원하는 기준에 부합하지 않아 수평센서를 추가적으로 설치하였다. INVENTOR를 바탕으로 3D 모델링을 통해 구조해석을 한 결과 작업자가 작업할 수 있는 최대 기울어짐 정도는 좌측 116.49Mpa, 우측 118.26Mpa로 나타났다. SThis study was carried out for the production of aerial work machinery in high place in the orchard. In the case of orchards, there are many unpaved roads and sloping grounds to solve the problem of overturning or safety problems when working in a orchard. For more stable operation, an automatic leveling system was designed. During the structural analysis, the horizontal sensor was installed in addition to the standard that we wanted. Based on the INVENTOR, the structural analysis through 3D modeling showed that the maximum tilt of the worker was 116.49Mpa on the left and 118.26Mpa on the right.

고소작업차의 원격 제어를 포함한 중앙집중식 컨트롤러 및 유압식 상승리프트 개발

이상식(Sang-Sik Lee),김준태(Jun-Tae Kim),박원엽(Won-Yeop Park) 한국정보전자통신기술학회 2017 한국정보전자통신기술학회논문지 Vol.10 No.3

본 연구는 선행 연구로 진행되었던 과수원 및 농경지에서 사용되는 고소작업차의 안정적인 요소를 설계하기 위하여 진행되었다. Auto leveling system과 수평센서를 이용하여 불규칙하고 경사가진 곳에서 안전하게 작업하기 위하여 유압식 상승리프트를 개발하였으며 고소작업대에서의 제어를 하기 위하여 원격 제어를 포함한 중앙집중식 컨트롤러의 개발을 진행하였다. 개발된 모듈을 통하여 고소작업대에서의 안정적 제어가 되는지 현장 시 운행을 실시하였으며, 고소 작업대의 구조해석을 통하여 작업자가 작업대에서 안전하게 작업을 할 수 있는 최대 적재 하중 및 균등 적재량을 제시함으로서 보다 안전에 대해 유의하도록 하였다. 각 부위별 설계 및 검증, 제작을 통하여 완성된 고소기계차의 현장 시운행을 통하여 프로토타입의 고소기계차를 제작하였고, 몇 가지의 수정 보완 사항을 통하여 연구를 지속적으로 행할 예정이다. This study was carried out to design the stable elements of the aerial work machinery used in the orchard and farmland which had been conducted in the previous research. A hydraulic lifting lift has been developed to work safely at irregular and inclined locations using an auto leveling system and a horizontal sensor. The development of a centralized controller including remote control has been carried out in order to control the elevated work platform. Through the developed module, we carried out on-site test run to check whether the control is stable in the elevation workbench. Through the structural analysis of the elevation workbench, the maximum load and the equal load amount that the worker can safely work on the workbench are presented.

상완이두근의 등장성 운동시 근피로인자로서 표면근전도의 저주파수대역 선정에 관한 연구

이상식 ( Sang Sik Lee ),이기영 ( Ki Young Lee ) 한국농업기계학회 2011 바이오시스템공학 Vol.36 No.4

Muscle fatigue is characterized as a progressive increase in discomfort arising from the active muscle at moderate load levels are maintained. The median frequency is the most commonly used as a parameter to describe muscle fatigue. However, the estimate of the median frequency is difficult to indicate muscle fatigue because of its high standard deviation and instability. This paper investigates the power changes of the appropriate low frequency band as a fatigue parameter in EMG during isotonic exercise. To select the appropriate band, linear regression lines are employed to calculate the slopes and the coefficient of determination. Three females and seven males volunteered to participate in surface EMG recordings placed on the biceps brachii and each recording experiment continued until their exhaustion. The results of experiment shows that the power changes of the selected low frequency band (15~45 Hz) have linear slopes and high determinant coefficients. Therefore, this fatiguing parameter using the power changes of the low frequency band is valid to measure the state of muscular fatigue.