코카콜라 경구 투여 및 내시경을 통한 코카콜라주입법으로 치료한 활동성 위궤양을 동반한 다발성 거대위석 1예

곽원건,박보라,강지훈,강현우,김재학,임윤정,이준규,고문수,이진호 동국대학교 의학연구소 2009 東國醫學 Vol.16 No.1

위석은 섭취된 이물질이 위내에서 응결된 덩어리로 일반적으로 내시경적 분쇄법 및 화학적 용해법이 치료방법으로 알려져 있다. 최근 코카콜라를 경구 또는 비위관을 통하여 주입하여 치료한 사례들이 보고되고 있으며 경구 투여 및 내시경을 이용하여 위석내 콜라를 주입하는 것이 치료기간 및 위석치료 성공률을 향상시킨다는 보고가 있다. 최근 저자들은 급성 위궤양이 확인된 환자의 거대위석을 코카콜라 경구 및 내시경 직접 주입법을 통하여 치료한 1예를 경험하였기에 보고하는 바이다. Gastric bezoars are concretions of foreign bodies found in the stomach, common method for the treatment was endoscopic fragmentation or chemical dissolution therapy, recently, there were reports on the treatment of bezoars by cola drinking or Coca-Cola gastric lavage, combination therapy with Coca.Cola drinking and endoscopic injection decreases duration of therapeutic time and increases dissolution rate, we report one case of active gastric ulcer with huge gastric Bezoars completely treated by drinking Coca.Cola with endoscopic injection

조혈모세포이식 후 발생한 주폐포자층 폐렴에 대한 고찰

주지현,최정현,이동건,백지연,고윤호,이혜정,김세희,신호진,박윤희,박지영,김유진,신완식,김춘추 대한감염학회 2001 감염 Vol.33 No.4

Background : Pneumocytitis cainii pneumonia (PCP) can occur in immunocompromised hosts especially such as AIDS or cancer patients. Although recent research had focused on PCP in AIDS patients, few studies have described the clinical presentations of PCP in recipients of stem cell transplantation (SCT). We evaluated the clinical manifestations of PCP in SCT patients admitted at St. Mary's hospital, Seoul, Korea. Methods : The medical records of 17 PCP patients undergoing SCT between Feb. 1998 and Feb. 2000 were reviewed. The diagnosis of PCP was confirmed through the demonstration of Pneumocytitis cainii via either cytology of brochoalveolar lavage (BAL) or histological technique of lung biopsy. CMV disease and CMV infection were confirmed by BAL culture and antigenemia respectively . Results : Seventeen patients were all recipients of allogeneic SCT and 7 of 17 patients were performed non-sibling SCT. Patients presented with symptoms including brief period (4 ∼23 days) of fever (76%), dyspnea (70%), cough (64%), and signs such as rare(58.8%), Sixteen patients (94%) had been receiving immunosuppressive agent such as cyclosporine A (64%) or Fk506 (35%) without PCP prophylaxis. Eleven patients (64%) were treated with corticosteroid with mean dose of 16 mg/day prednisolone and mean duration of 4.6 months after post-SCT period. Twelve patients were co-infected with CMV. Another co-infected miCroorganisms were Pseudomonas aeruginosa, Mycobacterium tuberculosis, herpes simplex virus, parainfluenza virus, Average duration of treatment with trimethoprim-sulfamethoxazole (TMP/SMX) was 21 ±9 days. Four patients died, and three of them were related with PCP. Conclusion : PCP developed frequently in patients who were taking immunosuppressive drug due to graft versus host disease or were not taking TMP/SMX prophylaxis. High risk patients showing fever, cough, or dyspnea should be considered to take early bronchoscopic intervention for detection of PCP. When treat for PCP, it also be considered to the possibility of coinfection such as CMV. (Korean J Infect Dis 33:273∼279, 2001)

Detection and quantification of structural damage under ambient vibration environment

Yun, Gun Jin Techno-Press 2012 Structural Engineering and Mechanics, An Int'l Jou Vol.42 No.3

In this paper, a new damage detection and quantification method has been presented to perform detection and quantification of structural damage under ambient vibration loadings. To extract modal properties of the structural system under ambient excitation, natural excitation technique (NExT) and eigensystem realization algorithm (ERA) are employed. Sensitivity matrices of the dynamic residual force vector have been derived and used in the parameter subset selection method to identify multiple damaged locations. In the sequel, the steady state genetic algorithm (SSGA) is used to determine quantified levels of the identified damage by minimizing errors in the modal flexibility matrix. In this study, performance of the proposed damage detection and quantification methodology is evaluated using a finite element model of a truss structure with considerations of possible experimental errors and noises. A series of numerical examples with five different damage scenarios including a challengingly small damage level demonstrates that the proposed methodology can efficaciously detect and quantify damage under noisy ambient vibrations.

An Improved Mode Accuracy Indicator for Eigensystem Realization Analysis (ERA) Techniques

Gun Jin Yun,Soon-Gie Lee,Shen Shang 대한토목학회 2012 KSCE JOURNAL OF CIVIL ENGINEERING Vol.16 No.3

In this paper, an improved mode accuracy indicator is presented to more efficiently distinguish physically true modes from computational spurious modes generated by Eigensystem Realization Analysis (ERA) methods. Since the system order of real-life structures is a priori unknown, the number of assumed poles is usually set to be two to ten times the number of true modes in the frequency range of interests. Thus, the modal identification process could create exceedingly large number of computational modes. For the reason, it makes it difficult for analysts to distinguish the physically true modes from the spurious modes. The proposed mode accuracy indicator could better narrow down the choice of true modes than existing indicators and particularly it shows better consistency for the structure having high damping ratios. A series of numerical tests are demonstrated for verification of the proposed mode accuracy indicator. In addition, the improved mode accuracy indicator is applied to an experimental decentralized modal identification of a laboratory-size 8-panel space frame structure.

A total strain-based hysteretic material model for reinforced concrete structures: theory and verifications

Gun Jin Yun,Thomas G. Harmon,Shirley J. Dyke,Migeum So 사단법인 한국계산역학회 2008 Computers and Concrete, An International Journal Vol.5 No.3

In this paper, a total strain-based hysteretic material model based on MCFT is proposed for non-linear finite element analysis of reinforced concrete structures. Although many concrete models have been proposed for simulating behavior of structures under cyclic loading conditions, accurate simulations remain challenging due to uncertainties in materials, pitfalls of crude assumptions of existing models, and limited understanding of failure mechanisms. The proposed model is equipped with a fully generalized hysteresis rule and is formulated for 2D plane stress non-linear finite element analysis. The proposed model has been formulated in a tangent stiffness-based finite element scheme so that it can be used for most general finite element analysis packages. Moreover, it eliminates the need to check that tensile stresses can be transmitted across a crack. The tension stiffening model is a function of the bar orientation and any orientation can be accommodated. The proposed model has been verified with a series of experimental results of 2D RC planar panels. This study also demonstrates how parameters of the proposed model associated with cyclic damage modeling influences the pinched cyclic shear behavior.

Detection and quantification of structural damage under ambient vibration environment

Gun Jin Yun 국제구조공학회 2012 Structural Engineering and Mechanics, An Int'l Jou Vol.42 No.3

In this paper, a new damage detection and quantification method has been presented to perform detection and quantification of structural damage under ambient vibration loadings. To extract modal properties of the structural system under ambient excitation, natural excitation technique (NExT)and eigensystem realization algorithm (ERA) are employed. Sensitivity matrices of the dynamic residual force vector have been derived and used in the parameter subset selection method to identify multiple damaged locations. In the sequel, the steady state genetic algorithm (SSGA) is used to determine quantified levels of the identified damage by minimizing errors in the modal flexibility matrix. In this study, performance of the proposed damage detection and quantification methodology is evaluated using a finite element model of a truss structure with considerations of possible experimental errors and noises. A series of numerical examples with five different damage scenarios including a challengingly small damage level demonstrates that the proposed methodology can efficaciously detect and quantify damage under noisy ambient vibrations.

A two-stage damage detection approach based on subset selection and genetic algorithms

Yun, Gun Jin,Ogorzalek, Kenneth A.,Dyke, Shirley J.,Song, Wei Techno-Press 2009 Smart Structures and Systems, An International Jou Vol.5 No.1

A two-stage damage detection method is proposed and demonstrated for structural health monitoring. In the first stage, the subset selection method is applied for the identification of the multiple damage locations. In the second stage, the damage severities of the identified damaged elements are determined applying SSGA to solve the optimization problem. In this method, the sensitivities of residual force vectors with respect to damage parameters are employed for the subset selection process. This approach is particularly efficient in detecting multiple damage locations. The SEREP is applied as needed to expand the identified mode shapes while using a limited number of sensors. Uncertainties in the stiffness of the elements are also considered as a source of modeling errors to investigate their effects on the performance of the proposed method in detecting damage in real-life structures. Through a series of illustrative examples, the proposed two-stage damage detection method is demonstrated to be a reliable tool for identifying and quantifying multiple damage locations within diverse structural systems.

A two-stage damage detection approach based on subset selection and genetic algorithms

Gun Jin Yun,Kenneth A. Ogorzalek,Shirley J. Dyke,Wei Song 국제구조공학회 2009 Smart Structures and Systems, An International Jou Vol.5 No.1

A two-stage damage detection method is proposed and demonstrated for structural health monitoring. In the first stage, the subset selection method is applied for the identification of the multiple damage locations. In the second stage, the damage severities of the identified damaged elements are determined applying SSGA to solve the optimization problem. In this method, the sensitivities of residual force vectors with respect to damage parameters are employed for the subset selection process. This approach is particularly efficient in detecting multiple damage locations. The SEREP is applied as needed to expand the identified mode shapes while using a limited number of sensors. Uncertainties in the stiffness of the elements are also considered as a source of modeling errors to investigate their effects on the performance of the proposed method in detecting damage in real-life structures. Through a series of illustrative examples, the proposed two-stage damage detection method is demonstrated to be a reliable tool for identifying and quantifying multiple damage locations within diverse structural systems.

Extradosed PSC Box 교의 시공단계해석

윤군진(Yun, Gun Jin),이완수(Lee Wan, Su),이종신(Lee, Jong Sin),김성찬(Kim, Sung Chan) 한국콘크리트학회 2001 한국콘크리트학회 학술대회 논문집 Vol.2001 No.11

사장교의 정적 비선형 해석과 초기형상결정해석

윤군진(Yun Gun-Jin),이완수(Lee Wan-Su) 대한토목학회 2001 대한토목학회논문집 A Vol.21 No.1A