• 한국전산구조공학회논문집
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• 제12권3호
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• pp.397-406
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• 1999

본 연구는 부구조화에 기초한 다단계 혼성 구조 재해석방법을 제시한다. 부구조화의 틀에 보존근사화의 각 항을 차원축소법의 기저로 한 보존 전역-부분근사화에 의하여 변위 산정의 정확성과 효율성을 확보하고, 이를 바탕으로 이미 구성된 응력-변위 관계식을 병용하는 혼성방식을 통하여 전체 설계의 중간 단계에서 반복되는 재해석 과정의 신뢰성을 높인다. 전체적으로 선형근사화와 상반근사화를 교차적용하는 1단계 보존근사화로부터 전역 근사화와 결합하여 구하는 변위산정과 그에 종속되는 행렬연산으로 산출하는 응력계산의 3단계로 이루어지는 본 방법은 대형 구조계를 대상으로 하여, 해석의 기본 틀로 부구조화 방법을 택하였으며, 몇 개의 예제들을 통하여 타당성 및 유용성을 검증하였다.

• 대한족부족관절학회지
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• 제22권2호
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• pp.55-61
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• 2018

Chronic lateral ankle instability is a major complication of acute ankle sprains, which can cause discomfort in both daily and sports activity. In addition, it may result in degenerative changes to the ankle joint in the long term. An accurate diagnostic approach and successful treatment plan can be established based on a comprehensive understanding of the concept of functional and mechanical instability. The patients' history and correct physical examination would be the first and most important step. The hindfoot alignment, competence of the lateral ligaments, and proprioceptive function should be evaluated. Additional information can be gathered using standard and stress radiographs. In addition, concomitant pathologic conditions can be investigated by magnetic resonance imaging. Conservative rehabilitation composed of the range of motion, muscle strengthening, and proprioceptive exercise is the main treatment for functional instability and mechanical instability. Regarding the mechanical instability, surgical treatment can be considered for irresponsible patients after a sufficient period of rehabilitation. Anatomic repair (modified $Brostr{\ddot{o}}m$ operation) is regarded as the gold standard procedure. In cases with poor prognostic factors, an anatomical reconstruction or additional procedures can be chosen. For combined intra-articular pathologies, arthroscopic procedures should be conducted, and arthroscopic lateral ligament repair has recently been introduced. Regarding the postoperative management, early functional rehabilitation with short term immobilization is recommended.

• 대한기계학회논문집A
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• 제20권6호
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• pp.1743-1752
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• 1996

In this paper, a precision inspection technique using CAD/CAI integration is proposed for the parts having very thin and sharp 3 dimensional curve features. The technique begings with feature reconstruction of turbine blades which have 3 dimensional combined feometry, such as splines, and thin circles. The alifnment procedures consistsb of two phases-rough and fine phases : rough phase alignment is based on the conventional 6 point5s probing on the clear cut surfacef, and fine phase alignment is based on the intial measurement on the 3 dimensional curved parts using an lterative measurement feed-back least sequares technique for alignment. Forf the analysis of profile tolerance of parts, the actual measured points are obtained by finding the closet points on the CAD geometry by the developed subdivision technique and the Tschebycheff norm is applied based on iterative fashion, giving accurate profile tolerance value. The developed inspection technique is applied to practical procedures of blade manufacturing and demonstrated high performance.

• Journal of Chest Surgery
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• 제29권8호
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• pp.927-930
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• 1996

인제의대 서울백병원에서는 1986년부터 1994년까지 말초동맥에 발생한가성동맥류환자 6례를 수술 치험하였다. 발생원인은 자상의 일차 봉합술 후 3례, 혈관에 도관삽입 후 2례, 골절상 후 고정 핀을 제거하기 위한 수술 후 1례였다. 발생부위는심부 대퇴동맥 2례, 총대퇴동맥 2례, 쇄골하동맥과 액와동맥에 각각 1례였다. 증상은 박동성 종괴가 4례에서 촉지되었고, 청진시 잡음은 3례, 동통과 종창이 2례, 압통이 1례에서 있었다. 이 중 5례에서 수술을 시행하였다. 수술은 2례에서 심부 대퇴동맥을 결찰하여 가성동맥류를 제거하였다. 단순 가성동맥류의 절제, 요피정맥을 연결하여 성형술, 복재정맥의 첩제를 이용한 성형술을 각각 1례에서 시행하여 가성동맥류를 제거하였다. 1례는 자연 치유되었다.

• 산경연구논집
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• 제10권5호
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• pp.7-20
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• 2019

Purpose - This study provides appropriate procedures for EFA to help researchers conduct empirical studies by using PLS-SEM. Research design, data, and methodology - This study addresses the absolute and relative sample size criteria, sampling adequacy, factor extraction models, factor rotation methods, the criterion for the number of factors to retain, interpretation of results, and reporting information. Results - The factor analysis procedure for PLS-SEM consists of the following five stages. First, it is important to look at whether both the Bartlett test of sphericity and the KMO MSA meet the qualitative criteria. Second, PAF is a better choice of methodology. Third, an oblique technique is a suitable method for PLS-SEM. Fourth, a combined approach is strongly recommended to factor retention. PA should be used at the onset. Next, it is recommended using the K1 criterion. In addition, it is necessary to extract factors that increase the total variance explanatory power through the PVA-FS. Finally, it is appropriate to select an item with a factor loading into 0.5 or higher and a communality of 0.5. Conclusions - It is expected that the accurate factor analysis processed for PLS-SEM as previously presented will help us extract more precise factors of the structural model.

• Geomechanics and Engineering
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• 제3권3호
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• pp.169-188
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• 2011

Response of buried flexible pipe-soil system is studied, through numerical analysis, with respect to deflection and buckling in a spatially varying soil media. In numerical modeling procedure, soil parameters are modeled as two-dimensional non-Gaussian homogeneous random field using Cholesky decomposition technique. Numerical analysis is performed using random field theory combined with finite difference numerical code FLAC 5.0 (2D). Monte Carlo simulations are performed to obtain the statistics, i.e., mean and variance of deflection and circumferential (buckling) stresses of buried flexible pipe-soil system in a spatially varying soil media. Results are compared and discussed in the light of available analytical solutions as well as conventional numerical procedures in which soil parameters are considered as uniformly constant. The statistical information obtained from Monte Carlo simulations is further utilized for the reliability analysis of buried flexible pipe-soil system with respect to deflection and buckling. The results of the reliability analysis clearly demonstrate the influence of extent of variation and spatial correlation structure of soil parameters on the performance assessment of buried flexible pipe-soil systems, which is not well captured in conventional procedures.

• 응용통계연구
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• 제21권3호
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• pp.509-521
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• 2008

평균과 분산이 동시에 변화할 수 있는 공정을 관리할 경우, 평균의 변화를 탐지하는 관리도와 분산의 변화를 탐지하는 관리도를 병행하여 사용하는 것이 일반적이다. 여러 연구자들이 하나의 관리도를 사용하여 공정 평균과 분산의 변화를 동시에 탐지할 수 있는 절차를 제안했는데, 이 논문에서는 이와 같은 관리도들을 소개하고 그 효율을 비교하였다. 그 결과 GLR 관리도 Omnibus EWMA 관리도 그리고 Interval 관리도는 충분히 좋은 효율을 가짐을 알 수 있었다.

• 대한족부족관절학회지
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• 제17권1호
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• pp.11-16
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• 2013

Freiberg's disease is a osteochondrosis of a metatarsal head that is recognized as primarily a disorder of the second metatarsal. It is seen more often in girls. Pain and limitation of motion of the affected joint is the predominant clincal feature. The radiographic appearance demonstrates from osteosclerosis in the early stage to osteolysis with collapse in the later stage. Conservative therapy may take the form of rest, a stiff shoe, and even a cast support to decrease the stress across the joint. Surgical intervention may also be of benefit. Surgery have been attempted either to modify the diseae process or to salvage the situation once the metatarsophalangeal joint develops degenerative changes. Metatarsophalangeal joint instability is common cause of forefoot pain that can develop in association with a traumatic episode and inflamatory tissue disorders as well as neighboring toe deformities. The second ray is by far the most frequently involved. The diagnosis can be made by clinical observation and physical examination including drawer test. Many surgical procedures have beem recommended when conservative treatment has failed. Procedures described range from soft tissue releases and tendon trasfer to the direct plantar plate repair combined with a Weil osteotomy.

• Advances in pediatric surgery
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• 제3권1호
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• pp.1-5
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• 1997

Regional lymphadenitis is the most common complication following BCG vaccination in this country. The literature describes controversial results with medical, surgical and combined therpy. The purpose of this study is to clarify the therapeutic effect of isoniazid(INH) after surgical procedures. The early and late postoperative complications of 136 children with lymphadenitis following BCG vaccination at the Taegu Fatima Hospital between March 1985 and February 1996 were reviewed. In 90 children, INH was given for 3-4 days before operation and for 3 months after surgery. In the other 46 cases, INH was not given during the pre- or postoperative period. Surgical procedures were excision or incision and currettage according to the states of lesions. Postoperative complications were fluid accumulation, wound infection, sinus formation and others. Complication rates were 14.4 % in INH-treated group and 13.0% of INH-nontreated group. The difference was not significant. There was no recurrence or other late complication in either groups. The result suggest that surgical excision or incision and currettage are sufficient for the treatment of regional lymphadenitis following BCG vaccination and postoperative INH therapy is not necessary.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2001년도 하계학술대회 논문집 D
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• pp.2123-2125
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• 2001

In thermal power plant, the efficiency of a combined power plant with a gas turbine increases, exceeding 50%, while the efficiency of traditional steam turbine plants is approximately 35% to 40%. Up to the present time, the PID controller has been used to operate this system. However, it is very difficult to achieve an optimal PID gain without any experience, since the gain of the PID controller has to be manually tuned by trial and error procedures. This paper focuses on the neural network tuning of the 2-DOF PID controller with a separated 2-DOF parameter (NN-Tuning 2-DOF PID controller), for optimal control of the Gun-san gas turbine generating plant in Seoul. Korea. In order to attain optimal control, transfer function and operating data from start-up, running, and stop procedures of the Gun-san gas turbine have been acquired, and a designed controller has been applied to this system. The results of the NN-Tuning 2-DOF PID are compared with the PID controller and the conventional 2-DOF PID controller tuned by the Ziegler-Nichols method through experimentation. The experimental results of the NN-Tuning 2-DOF PID controller represent a more satisfactory response than those of the previously-mentioned two controller.