고립성 폐 결절로 나타난 경화성 혈관종의 폐엽 절제술에 의한 치험 1예 : A case report

황은구,이송암,황재준,김상윤,권혁중,김요한 건국대학교 의과학연구소 2004 건국의과학학술지 Vol.13 No.-

Patient was sixty-eight years old female. She was transferred to our department to resect the solitary pulmonary nodule on right lower lobe. Intraoperative frozen-section revealed bronchioloalveolar carcinoma. So, we performed right lower lobectomy and mediastinal lymph node dissection. Permanent pathologic diagnosis of this patient was sclerosing hemangioma. We report experience of treatment of sclerosing hemagioma presenting solitary pulmonary nodule by lobectomy with the review of literatures.

담즙정체성 간염의 임상적 양상

최선택,은종렬,임상우,김봉준,이헌주,구미진,최준혁 영남대학교 기초/임상의학연구소 2001 Yeungnam University Journal of Medicine Vol.18 No.1

Background: Cholestatic hepatitis is failure of bile to reach the duodenum with hepatocellular damage and no demonstrable obstruction of the major bile ducts. The prognosis is usually good with recovery in less than 4 weeks after withdrawal of the offending drug. However, a prolonged course lasting over 3 months is possible and, in rare cases, progression to ductopenia with development of a vanishing bile duct syndrome occurs. A differential diagnosis with other causes of Chronic liver disease is needed. Materials and Methods: From January 1991 through Jaunary 2000, 14 patients diagnosed as cholestatic hepatitis by liver biopsy were inclouded. The possible causative drug, clinical features, laboatory findings, and progression of cholestatic hepatitis were evaluated. The semiquantitative study of liver lesions was performed by two independent observers. Results: Causes of cholestatic hepatitis are 5 cases of oriental medicine, 3 cases of anti-tuberculosis medication, 1 case of ticlopidine and antibiotics and 4 cases of unknown causes. The clinical features of cholestatic hepatitis were jaundice, itching, urine color change, and general weakness. During 6 to 30 months, LFT of 5 patients showed prolonged elevation. Elevated total cholesterol ≥250 mg/dL in 6 patients, pheripheral blood eosinophilia in 5 patients, auto-antibody positive in 6 patients were observed respectively. The biopsies showed intralobular bilirubinostasis with a mixed portal inflammatory infiltration. Conclusion: In cholestatic hepatitis. durations of abnormal LFT are variable regardless of causative drugs. If cholestatic hepatitis progresses toward chronic course, viral hepatitis, primary biliary cirrhosis, and autoimmune hepatitis should be differentially diagnosed and sequential liver biopsies are needed.

Effect of Strain Rate Variation on Fatigue Life of Spot Welded Joint

Song, Joon Hyuk,Yu, Hyu Sun,Kang, Hee Yong,Yang, Sung Mo Trans Tech Publications, Ltd. 2005 Key Engineering Materials Vol.297 No.-

<P>Resistance spot welding is used extensively to fasten sheet for automotive applications. In many components, these welds should maintain their integrity under severe loading conditions. However fatigue strength of the spot welded joint is considerably lower than base metal due to stress concentration at the nugget edge, and is influenced by its geometrical and mechanical factors such as welding condition and etc. In this paper, it is estimated that effect of strain rate variation on fatigue life of spot welded joint. The analytical method proposed to overcome above difficult using lethargy coefficient concept for evaluating the fatigue life cycle of spot welded joint. The reliability of the life cycle is completed by comparing with the life cycle obtained by fatigue test for the specimen with the welding current. And the above procedure is numerically extended to get the life of dynamic strain rate region.</P>

An improved approach for valuing American options and their greeks by Least-squares Monte Carlo simulation

Joon Hyuk Song,Young Soo Choi 한국증권학회 2008 한국증권학회지 Vol.37 No.2

Cardiovascular beriberi: rare cause of reversible pulmonary hypertension

Joon Hyuk Song,Sang Soo Cheon,Myung Hwan Bae,Jang Hoon Lee,Dong Heon Yang,Hun Sik Park,Yongkeun Cho,Shung Chull Chae 영남대학교 의과대학 2014 Yeungnam University Journal of Medicine Vol.31 No.1

Cardiovascular beriberi is caused by thiamine deficiency and usually presents as high cardiac output failure associated with predominantly right-sided heart failure and rapid recovery after treatment with thiamine. Because of its rarity in developed countries, the diagnosis can often be delayed and missed. We recently experienced a case of cardiovascular beriberi with pulmonary hypertension which successfully treated with thiamine infusion. A 50-year-old man with chronic heavy alcoholics was refered to our department for dyspnea with mental change. Echocardiography showed marked right ventricular (RV) dilatation and flattening of the interventricular septum with a D-shaped deformation of the left ventricle. Moderate tricuspid valve regurgitation was found and estimated RV systolic pressure was 52 mm Hg. Because of his confused mentality and history of chronic alcohol intake, neurological disorder due to thiamine deficiency was suspected and intravenous thiamine was administered and he continuously received a daily dose of 100 mg of thiamine. Follow up echocardiography showed marked reduction of RV dilatation and improvement of a D-shaped deformation of the left ventricle. He finally diagnosed as cardiovascular beriberi on the basis of dramatic response to intravenous thiamine. Thiamine deficiency can cause reversible pulmonary hypertension, and can still be encountered in the clinical setting. Thus high index of suspicion is critically needed for diagnosis.

Cardiovascular beriberi: rare cause of reversible pulmonary hypertension

Song, Joon Hyuk,Cheon, Sang Soo,Bae, Myung Hwan,Lee, Jang Hoon,Yang, Dong Heon,Park, Hun Sik,Cho, Yongkeun,Chae, Shung Chull Yeungnam University College of Medicine 2014 Yeungnam University Journal of Medicine Vol.31 No.1

Cardiovascular beriberi is caused by thiamine deficiency and usually presents as high cardiac output failure associated with predominantly right-sided heart failure and rapid recovery after treatment with thiamine. Because of its rarity in developed countries, the diagnosis can often be delayed and missed. We recently experienced a case of cardiovascular beriberi with pulmonary hypertension which successfully treated with thiamine infusion. A 50-year-old man with chronic heavy alcoholics was refered to our department for dyspnea with mental change. Echocardiography showed marked right ventricular (RV) dilatation and flattening of the interventricular septum with a D-shaped deformation of the left ventricle. Moderate tricuspid valve regurgitation was found and estimated RV systolic pressure was 52 mm Hg. Because of his confused mentality and history of chronic alcohol intake, neurological disorder due to thiamine deficiency was suspected and intravenous thiamine was administered and he continuously received a daily dose of 100 mg of thiamine. Follow up echocardiography showed marked reduction of RV dilatation and improvement of a D-shaped deformation of the left ventricle. He finally diagnosed as cardiovascular beriberi on the basis of dramatic response to intravenous thiamine. Thiamine deficiency can cause reversible pulmonary hypertension, and can still be encountered in the clinical setting. Thus high index of suspicion is critically needed for diagnosis.

Tensile properties of recycled-carbon fiber reinforced polypropylene composites by injection molding method

Joon-Hyuk Song,Dong-Guen Lee,Ho-Hyung KooK,Na-Ra Park,Myeong-Han Yoo,Min-Seok Moon,Won-Tae Kim,Je-Ha Oh,Jin-Soo Kim 한국생산제조학회 2018 한국생산제조시스템학회 학술발표대회 논문집 Vol.2018 No.10

An Empirical Evaluation of Fiscal Sustainability Near and Far

Joon Hyuk Song 한국경제학회 2009 The Korean Economic Review Vol.25 No.1

상태-공간모형을 이용한 Nelson-Siegel 이자율 기간구조 추정과 예측

송준혁 ( Joon Hyuk Song ) 한국파생상품학회(구 한국선물학회) 2011 선물연구 Vol.19 No.3

본 논문에서는 Nelson-Siegel 모형의 횡단면적 제약을 완화하기 위해 시계열적 특성을 반영한 상태-공간 모형을 설정하여 수익률곡선을 추정하고 미래 수익률에 대한 예측성과를 비교해 보았다. 자료를 분석한 결과 Nelson-Siegel 요인들은 수익률곡선의 수준, 기울기 및 곡률을 잘 표현하고 있으며 수익률곡선의 변곡은 대략 55개월 근처에서 형성되어 있음이 관찰되었다. 한편 Nelson-Siegel의 개별요인들에 대한 단위근 검정 결과 이들 요인 모두 단위근이 존재하였으나 각 요인들의 차분에 대한 단위근 검정결과는 모두 안정적인 시계열로 나타나 이들 요인들은 I(l) 변수들로 판명되었다. 상태-공간 Nelson-Siegel 모형이 수익률곡선을 예측하는 데 얼마나 유용한 지를 살펴보기 위해 표본외 예측을 수행하고 이를 임의보행, Fama-Bliss 그리고 Cochrane-Piazzesi 모형과 비교한 결과 Fama-Bliss 모형의 예측력이 가장 열등한 것으로 나타났다. Nelson-Siegel 모형과 임의보행 모형의 예측성과는 예측시계에 따라 상이하게 나타났는데 단기에서는 Nelson-Siegel 모형이, 장기에서는 임의보행 모형의 예측성과가 우수한 것으로 관찰되었다. This paper estimates a Nelson-Siegel model under the state-space representation in order to circumvent the shortcomings of the conventional Nelson-Siegel model and evaluates the predictive ability of the estimated model. The results indicate that the estimated Nelson-Siegel time-varying three factors have close relations to their counterparts: level, slope and curvature and the inflection of the Korean yield curve is located around the maturity of 55-month. Meanwhile, each factor is found to have unit-root but differenced-factors do not show signs of unit-roots, hence proved I(1) series. In order to assess the efficacy of the estimated model, we compare the yield prediction from our model with several natural competitors: random walk, Fama-Bliss, and Cochrane-Piazzesi. With respect to out-of-sample performance, Fama-Bliss model proves to be the worst in term structure forecasts in Korea. The predictive performance differs between the random walk and the state-space Nelson-Siegel model depending on the forecast horizon lengths. At the shorter horizon, the state-space Nelson-Siegel model outperforms the random walk, but the table is turned in the longer horizon.

경제학에서 분리가능 함수의 의의와 응용

송준혁 ( Joon Hyuk Song ) 한국경제교육학회 2014 경제교육연구 Vol.21 No.1

본고에서는 학부 및 석사 과정에서 다루는 수리 모형에서 암묵적으로 가정하고 사용하고 있는 효용함수의 분리가능(separability)에 대한 의의 및 기능을 설명하고 이를 이용한 몇 가지 응용 사례를 소개하고자 한다. 함수의 분리가능에 대한 가정은 소비자 최적화 문제에서의 닫힌 해와 실증 분석에 있어서의 모수 식별에 유용한 수학적 도구이나 이러한 가정은 결국 도출하고자 하는 해의 함수적 형태를 사전적으로 제약한다는 측면에서 효용함수의 분리가능에 대한 보다 정확한 이해가 선행될 필요가 있다. 경제학에서 사용하고 있는 분리가능은 가격체계에 일정한 가정을 부여하는 Hicksian 분리가능과 효용함수의 형태를 일정하게 제약하는 기능적(Functional) 분리가능으로 대별된다. Hicksian 분리가능은 통상 시점간 최적화 문제를 다룰 때 자주 나타나는 반면 기능적 분리가능은 주로 총량 변수 또는 복합재를 통한 가격 및 수량 지수를 구할 때 자주 사용된다. 본고에서 설명하는 분리가능에 대한 수리적 모형과 응용사례는 학부와 대학원에서 필요에 따라 다양한 형태로 변형하여 사용함으로써 경제 모형에 대한 이해도를 높이는데 도움을 줄 수 있을 것으로 기대한다. We present the implications and workings of the separability assumptions in the utility functions addressed in the mathematical models of the undergraduate and graduate economics courses and introduce several applications of them. Granting that separability is very convenient tool to both deriving closed-form solutions in the consumers’ optimal choice problem and identifying parameters in empirical studies, one should also acknowledge that this assumption levies some restrictions on the shape of optimal condition ex-ante. Hence, the underpinning of the assumption should be clearly understood in advance to make the best of it. Broadly speaking, there are two strands in the notion of separability applied in economics. Hicksian separability is the one which imposes restrictions on the price systems and functional separability is the other one which regulates the shape of utility functions. While Hicksian separability is usually seen in the inter-temporal choice problems, functional separability is widely employed in the index problems in aggregate or composite goods.