전자화폐의 확산에 따른 주요 쟁점에 관한 一考

송경석,김영훈 한국통상정보학회 2003 통상정보연구 Vol.5 No.2

The main issues addressed in this paper are as follows : First, this paper makes a distinction among types of e-money, IC card type versus Network type, open-loop type versus closed-loop type, online type versus offline type and accountable type versus unaccountable type, and analysis the clear and accurate criterion. Second, generally speaking, e-money is a claim on originator of e-money and not legal tender, so, delivery of e-money by itself does not relieve of monetary obligation. Because it is not easy to define e-money, by now there are many definitions of e-money. there is a legal uncertainty accordingly and then it is not easy to find proper law applicable to resolve a particular issue. As a result, many problems relating to e-money would be solved through analogical application of the most proper law among the laws that apply to the cash, checks, credit card, or fund transfer after analyzing type of e-money at issue. This paper studies the methods on diffusion of the utilization of electronic money. To diffuse the usage of electronic money, it needs prerequisitely as a basic conditions independence of electronic money, non-reusability, and anonymity. And also as a additional conditions it needs usability in the offline commerce, transferability, divisibility. And now electronic money is used very actively, but still has many law problems such as protections of consumer, law enforcement, supervisory, etc. So electronic money has called as money, but it is sure that electronic money is not a legal tender. So to facilitate the economic function of the electronic monet it is need to supplement the electronic money in the legal sides.

자궁내 발육지연이 있는 출생체중 2,500 g 이상인 환아의 주산기 예후에 관한 연구

송태복,조명숙,하진아,윤대석,김철홍,김윤하,최영륜 全南大醫大 2004 전남의대학술지 Vol.40 No.1

열림 모드에 대한 형상 최적화

한석영,송시엽 한국공작기계학회 2001 한국공작기계학회 춘계학술대회논문집 Vol.2001 No.-

The relationship between structural geometry and number of life cycles to failure is investigated to improve the fatigue life of structural components. The linear elastic fracture mechanics(LEFM) approach is integrated with shape optimal design methodology. The primary objective of this study is to decide an optimal shape for enhancing the life of the structure. The results from LEFM analyses are used in the fatigue model to predict the life of the structure before failure is occurred. The shape of the structure is optimized by using the growth strain method. Relevant issues such as problem formulation, finite element modeling are explained. Three design examples are solved, and the results show that, with proper shape changes, the life of structural systems subjected to fatigue loads can be enhanced significantly.

강섬유보강 철근 콘크리트보의 휨거동 해석

차희석,송영석 慶南大學校 附設 工業技術硏究所 1998 硏究論文集 Vol.16 No.-

강섬유보강 철근 콘크리트 보의 해석에 있어서 강섬유의 혼입으로 인한 휨 압축응력과 휨 인장응력의 증가가 있음에도 불구하고 기존의 연구들은 휨 인장응력의 증가만을 고려하였다. 따라서 본연구에서는 기존의 연구와는 달리 압축축의 휨 응력 증가를 고려하여 압축영역의 응력블록을 사다리꼴로 가정하였다. 이를 수식화하여 컴퓨터 프로그램을 이용한 수치해석결과는 이전의 연구에 비해 실험결과치에 더 가까이 접근함을 알 수 있었다. 이로써 강섬유보강 철근 콘크리트 보의 해석시에는 휨압축응력의 증가를 고려하여야 함이 실증되었다. In this study, analysis of reinforced steel fiber concrete beam, considered the increasing flexural compressive stress in company with tensile stress and stress block in compressive zone assumed trapezoid shape. But existing study just considered tensile stress in spite of increasing flexural compressive stress. In comparing and analyzing this experimentation and existing experimentation with computer program, we found that the result of this study was very closer actual value than existing value. Therefore, we should consider that the flexural compressive stress increase when we explain the reinforced steel fiber concrete beam.

하수 염소 소독시 소독부산물 발생 특성

백영석,송민형,정경훈,권동식,이기공 한국물환경학회 2004 한국물환경학회지 Vol.20 No.3

This study was performed to investigate the disinfection efficiency and the formation characteristics of disinfection by-products(DBPs) by chlorination in the sewage effluent. The effluent was sampled from the sewage treatment plants operated in the activated sludge process and the advanced sewage process. The type of DBPs investigated were Trihalomethanes(THMs), Dichloroacetonitrile(DCAN), Chloral hydrate(CH), Dichloroacetic acid(DCAA), Trichloroacetic acid(TCAA). Major findings are as follows. First, the optimum injection concentration for chlorination in sewage effluent were found to be in the range 0.5 ~ 1.0 ㎎ Cl₂/L. Also, It was found that the chlorine dosage in the effluent of activated sludge process was higher than in the effluent of advanced sewage process. Second, the maximum formation concentration of THMs were 12.7 μg/L. The THMs formation reaction was finished in a short time of several seconds and chloroform was mainly formed. Also, it was found that the concentration of ammonium nitrogen is higher, the concentration of THMs is lower. Third, it was found that DCAA and TCAA were mainly formed as DBPs by disinfection.

항갑상선제로 치료한 그레이브스병 환자의 관해예측인자

남일송,윤여일,김선규,김용현,이주영,목지오,윤석기,김철희,김영선,변동원,서교일,유명희 순천향의학연구소 2001 Journal of Soonchunhyang Medical Science Vol.7 No.2

Background: Most cases of Graves' disease have been treated by antithyroid drugs in Korea. The major drawbacks of antithyroid drugs are the relative high rate of relapse and the inconvinience of long term therapy. Measurement of TBII and TRH stimulation test have been considered as the most reliable tests predicting relapse, but the predictive power is not high enough to use in clinical situation. This study was performed to find good prognostic indicators in Graves' disease patients after the discontinuation of antithyroid drug therapy. Subjects and methods : We restrospectively evaluated 96 patients with Graves' disease who showed normal TRH test at the end of antithyroid drug therapy and were followed for more than one year. Serum T3, T4, T3/T4 ratio, TBII, Anti-TPO Ab and TGAb levels were measured at the time of diagnosis and at the end of therapy. Two to three months after withdrawal of antithyroid medication, serum TSH and free T3 responses to TRH were examined. These parameters were compared between the relapse group and the remission group. Results : Among the 96 patients, 22 patients(22.9%) relapsed(Group Ⅱ) and 74 patients(77.1%) remained in remmision(Group Ⅰ). No significant difference was observed between the relapse and the remission group in clinical parameters, serum T3, T4, TSH, T3/T4 ratio, TBⅡ and Anti-TPO Ab determined before and after treatment. Serum TSH and free T3 levels measured after TRH stimulation were also similar in both groups. Serum TGAb levels determined at the end of treatment were significantly higher in the remission group(p<0.05). Relapse following the discontinuation of therapy occured within 24 months in 72.7% of the relapsed cases. After 24 months, relapse rate was reduced significantly. Conclusion : These results suggest that high serum TGAb levels could be a favorable prognostic indicator for the long term remission of Graves' disease treated with antithyroid drugs, and may suggest that Hashimoto's thyroiditis is combined with Graves' disease in those patients.

급성심근경색증에서 운동부하 심전도상 유발된 ST절 변화와 심근관류와의 관계

임도선,김영훈,김병회,김미양,김수미,황교승,안정천,송우혁,박창규,서홍석,심완주,오동주,노영무 대한순환기학회 1998 Korean Circulation Journal Vol.28 No.5

공기압 실린더의 위치제어기 선정에 관한 연구

김일수,김기우,정영재,손준식,송창재,박주석 한국공작기계학회 1999 한국생산제조학회지 Vol.8 No.6

This paper concentrates on the position control of a pneumatic cylinder under parameter variation. A closed-loop control is proposed to design the different controllers(P, PI, PID, PD controller) in order to choose the best controller based on the fast and accurate control of the system. It is shown that the control algorithm is robust and effective in attaining the fast and accurate position control of system under time-dependent parameter variation. Experimental results showed that PD controller law is effective to obtain the fast response and to increase the stability of the system. The method is a useful control algorithm which always automatically adjusts the position control in accordance with the error, using carrier wave of triangle type regardless of changes on the operating condition and physical differences between components.

급성심근경색증을 가진 한국인에 있어 Chlamydia Pneumoniae 감염의 영향에 대한 연구

이은미,오동주,황교승,안정천,송우혁,임도선,박창규,김영훈,서홍석,심완주,노영무,정희진,김우주,김종헌,송기준 대한순환기학회 2000 Korean Circulation Journal Vol.30 No.4

조혈모세포이식 환자에서의 기계 환기의 위험 인자 : Assessment of Risk Factors

안중경,이홍기,황정혜,박세훈,이효락,송서영,이순일,박준오,김기현,김원석,정철원,임영혁,강원기,박근칠 대한조혈모세포이식학회 2002 대한조혈모세포이식학회지 Vol.7 No.1

연구배경: 조혈모세포이식을 시행한 환자에서 집중 치료 시 예후가 매우 나쁜 것으로 알려져 있고, 기계 환기는 강력한 사망 예측 인자로서 보고되고 있다. 그러나 현재까지 이식 환자에서 기계 환기의 위험 인자를 밝힌 연구는 매우 드물다. 따라서 기계 환기를 시행한 조혈모세포이식 환자의 임상적 특징을 살펴보고 기계 환기에 대한 위험 인자를 알아보고자 하였다. 방법: 삼성서울병원에서 조혈모세포이식을 시행한 환자 중 기계 환기를 시행한 23명과 기계 환기를 시행하지 않은 142명을 대상으로 후향적 연구를 시행하였다. 기계 환기에 대한 위험 인자의 여부에 관해서는 chi-square 또는 Fisher's exact 검정을 시행하였으며 기계 환기에 대한 각 위험 인자의 영향에 관해서는 다중로지스틱 회귀분석을 시행하였다. 결과: 기계 환기를 시행한 23명의 환자 중 30일째 생존자는 1명이었고 6개월째 생존율은 0%였다. 생존자와 사망자 모두에서 다기관 기능부전이 관찰되었으며, APACHE II 점수와 SAPS II 점수에 의한 예측 사망률은 각각 56%, 59%였다. 조혈모세포이식 후 기계 환기의 위험 인자로는 선행 질환이 혈액질환, 부분불일치 동종이식, 간정맥폐색성질환, 이식 전 질병 상태가 재발하였거나 약물에 반응하지 않는 경우였다. 다중로지스틱 회귀분석 결과 기계 환기의 위험 인자로 통계적으로 유의한 차이를 나타낸 것은 단지 부분불일치 동종이식을 시행한 경우였다. 결론: 현재까지 조혈모세포이식 환자에서 집중 치료의 역할에 대해서는 확실히 정립되어 있지는 않으며, 이식 환자에서 기계 환기는 강력한 사망 예측 인자이다. 따라서, 조혈모세포이식을 시행한 환자에서 기계 환기의 위험 인자와 불량한 예후 인자를 고려하여 기계 환기 여부에 대한 신중한 결정을 내려야 한다. Background: Respiratory failure requiring mechanical ventilation is a frequent, critical complication of hematopoietic stem cell transplantation (HSCT). Patients who require mechanical ventilatory support after HSCT generally have a very poor prognosis. Mechanical ventilation in HSCT recipients is a strong predictive factor of mortality. The objectives of this study are to describe clinical characteristics of HSCT recipients undergoing mechanical ventilation and to identify the risk factors for mechanical ventilatory support after HSCT. Methods: We performed a retrospective chart review of all patients >15 yrs old who received HSCT at Samsung Medical Center and subsequently required mechanical ventilatory support between 1996 and 2001. Results: Thirty-day mortality rate in HSCT recipients undergoing mechanical ventilation was 95.6%. The mean predictive mortality rates of APAHCE II score and SAPS II score were 56% and 59%, respectively. Reasons for mechanical ventila-tion were sepsis (47.8%) followed by fungal infection (13%) and diffuse alveolar hemorrhage (8.7%). Univariate analysis identified relapsed or refractory diseases at HSCT, hematologic disease, hepatic venoocclusive disease and allogeneic or HLA-mismatched transplant as significant risk factors for mechanical ventilation. On multivariate logistic regression analysis, only allogeneic mismatched transplant remained significant. Conclusion: Overall outcome of HSCT recipients undergoing mechanical ventilation is very poor. Therefore, the risk factors and the poor prognostic factors for mechanical ventilation should be taken into account in making further treatment decision for HSCT recipients requiring mechanical ventilation.