• Journal of the Korean Arthroscopy Society
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• v.10 no.2
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• pp.165-172
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• 2006

Purpose: The purpose of this study is to evaluate the effects of intratunnel fixation in the tibial side on the arthroscopic ACL reconstruction with quadruple hamstring tendon at the second look arthroscopy. Materials and Method: From Dec 1999 to May 2005, we arthroscopically reexamined 32 cases who had been done arthroscopic ACL reconstruction with quadruple hamstring tendons. Hamstring tendons of all cases were fixed at femoral side with RigidfixTM. At the tibial side hamstring tendons were fixed only Post-tie (Group I) or Post-tie combined with IntrafixTM (Group II). At the time of second look arthroscopy mean age of cases was 30 years and mean duration for second look arthroscopy was 21.3 months. We analyzed the results with IKDC score, KT-1000 arthrometer under anesthesia, Telos stress radiography, tibial tunnel widening on the radiography and second look arthroscopic findings. Results: Group II had more superior than group I at side to side differences with KT-1000 and Telos stress radiograph, IKDC score, but the differences were insignificant. At arthroscopic evaluation, Group ll also had more superior than group I at graft tension and graft appearance, graft synovialization, but the differences were insignificant. Tibial tunnel widening in the knee AP radiograph was 2.3 mm in Group I and 1.7 mm in Group II and the difference was significant. (P=0.042) Conclusions: Additional procedure of tibial intratunnel fixation in arthroscopic ACL reconstruction with autogenous hamstring tendon significantly prohibited from tibial tunnel widening but clinical results, radiologic joint stability, findings in second look arthroscopy were insignificantly different. We concluded that Post-tie itself induced satisfactory clinical results, joint stability and graft maturation and that tibial tunnel widening did not affect the results.

• Journal of the Korea Society of Computer and Information
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• v.13 no.4
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• pp.19-30
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• 2008

Branch history is one of major input vectors in branch prediction. Therefore, the Proper use of branch history plays a critical role of improving branch prediction accuracy. To improve branch prediction accuracy, this paper proposes a new branch history management policy, based on interrelationship analysis of instructions. First of all, we propose three different algorithms to analyze the relationship: register-writhing method, branch-reading method, and merged method. Then we additionally propose variable input gshare predictor as an implementation of these algorithms. In simulation part, we provide performance differences among the algorithms and analyze their characteristics. In addition, we compare branch prediction accuracy between our proposals and conventional fixed input predictors. The performance comparison for optimal input branch predictor is also provided.

• Journal of the Society of Naval Architects of Korea
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• v.37 no.4
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• pp.92-105
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• 2000

A study for the structural strength evaluation on the slender doubler plate has been performed through the systematic evaluation process. In order to estimate the proper static strength of doubler plate subjected to the longitudinal in-plane compression, elasto-plastic large deflection analysis is introduced including the contact effect between main plate and doubler. The characteristics of stiffness and strength variation are discussed based on their results. Also, in order to compare the doubler structure with the original strength of main plate without doubler, a simple formula for the evaluation of the equivalent flat plate thickness is derived based on the additional series analysis of flat plate structure. Using this derived equation, the thickness change of a equivalent flat plate is analyzed according to the variation of various design parameters of doubler plate and some design guides are suggested in order to maintain the original strength of main plate without doubler reinforcement. Finally, correlation between derived equivalent flat plate formula and the developed buckling strength formulas by author et al. is discovered and these relations are formulated for the future development of simple strength evaluation formula of doubler plate structure.

• The korean journal of orthodontics
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• v.38 no.5
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• pp.304-313
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• 2008

Objective: The purpose of this study was to evaluate the stress distribution in bone and displacement distribution of the miniscrew according to the length and number of the miniscrews used for the fixation of miniplate, and the direction of orthodontic force. Methods: Four types of finite element models were designed to show various lengths (6 mm, 4 mm) and number (3, 2) of 2 mm diameter miniscrew used for the fixation of six holes for a curvilinear miniplate. A traction force of 4 N was applied at $0^{\circ}$, $30^{\circ}$, $60^{\circ}$ and $90^{\circ}$ to an imaginary axis connecting the two most distal unfixed holes of the miniplate. Results: The smaller the number of the miniscrew and the shorter the length of the miniscrew, the more the maximum von Mises stress in the bone and maximum displacement of the miniscrew increased. Most von Mises stress in the bone was absorbed in the cortical portion rather than in the cancellous portion. The more the angle of the applied force to the imaginary axis increased, the more the maximum von Mises stress in the bone and maximum displacement of the miniscrew increased. The maximum von Mises stress in the bone and maximum displacement of the miniscrew were measured around the most distal screw-fixed area. Condusions: The results suggest that the miniplate system should be positioned in the rigid cortical bone with 3 miniscrews of 2 mm diameter and 6 mm length, and its imaginary axis placed as parallel as possible to the direction of orthodontic force to obtain good primary stability.

• The Journal of the Korean bone and joint tumor society
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• v.17 no.1
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• pp.44-50
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• 2011

Purpose: To compare clinical outcomes of the tumor prosthetic replacement and osteosynthetic fixation for pathologic fracture of skeletal metastatic lesion of the proximal femur. Materials and Methods: From 1994 May to 2009 May, medical records of 22 patients who underwent tumor prosthetic replacement with tumor resection (group 1) and 15 others (16 hips) who underwent osteosynthetic fixation without tumor resection (group 2) were reviewed. The mean age of overall patients were 59 (group 1) and 60 (group 2). Mean follow up periods were 23 and 11 months. The oncological and functional results were evaluated with Kaplan-Meier methods and Musculoskeletal Tumor Society (MSTS) scoring system, 1993. The statistical evaluation was assessed with Log rank test and t-test. Results: The mean survival periods were 24 months in group 1 and 11months in group 2. The 1 year survival rates were 86% in group 1 and 50 % in group 2, and 2 year survival rates were 29.7% in group 1 and 9.4% in group 2. The mean MSTS functional score were 26.4 (19-30), 87.9% in group 1 and 15.3 (10-23), 51.0% in group 2. Conclusion: The results of tumor resection and prosthetic replacement in selected cases was better than osteosynthetic fixation without tumor resection for metastatic bone tumors around proximal femur in oncological and functional aspects.

• The Journal of the Korea Contents Association
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• v.5 no.4
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• pp.219-226
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• 2005

With the rise of interest in sports and introduction of a five-day duty service, it is. increasing the desire for leisure and well-being recently. In this paper, 1 design and implement a baseball broadcasting system for PDAs to offer a sports broadcasting service using wireless network. The implemented baseball broadcasting system is composed of PDA clients, a relay reporter, and a relay server. Users can search and retrieve baseball-related information as well as relay broadcasting information using PDA.

• Proceedings of the Korean Vacuum Society Conference
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• 2015.08a
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• pp.103.2-103.2
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• 2015

10-3 Pa 이하의 고진공 환경과 $180^{\circ}C$ 이하의 극저온 환경에서 대형정지궤도위성의 고온 열평형 환경구현을 위한 열제어패널이 설계되었다. 열제어패널은 가로 2.2 m, 세로 2.6 m, 두께 2 mm의 구리판에 구리 튜브가 브레이징되어 있는 형태로 설계되었으며, 지상에서 6 m 이상의 높이에 설치되고 위성의 위치에 따라 이동이 가능해야 하기 때문에, 별도의 지지 구조물이 함께 설계되었다. 따라서, 열제어패널 설치 및 고정을 위한 지지구조물의 경우 160 kg의 무게를 견뎌내야 하며 이동 및 설치에 있어 구조적인 안전성이 확보 되어야 한다. 이에 본 연구에서는 상용유한요소해석 프로그램을 사용하여 열평형시험 시 위성체 상단부의 고온 환경모사를 위한 열제어패널 지지구조물에 대한 구조 안전성을 확인 하였다.

• Archives of design research
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• v.13
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• pp.1-12
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• 1996

환경을 고려하는 제품개발에 대한 시대적 요구는 자연스럽게 그린 디자인 개념을 형성하게 되었고, 이러한 그린 디자인에 대한 관심이 디자인의 가치기준을 근본적으로 변화시켜 나갔다. 또한 소비촉진을 부추겨 환경파괴에 일익을 담당했던 디자인은 환경문제를 고려한 새로운 디자인철학을 바탕으로 환경을 위한 실천노력이 요구되는 시점이다. 이에 본 논문에서는 환경문제를 고려한 실천노력의 하나로 플라스틱을 주요 소재로 사용하는 제품 디자인의 제품설계단계에서 폐기물을 사전에 줄이고, 발생된 폐기물 중 재생 및 재활용이 가능한 재료를 최대한 회수하여 효율적으로 자원화 할 수 있도록 구체적인 재활용 설계방법을 모색해 보았다. 연구의 진행은 재활용 설계 시 고려해야 할 요소를 재료에 관한 문제, 구조에 관한 문제, 2차 가공에 관한 문제로 나누어 진행하였다. 재료의 문제는 플라스틱 재료의 재활용 범위를 검토해보고 재활용을 가능하게 하는 재료의 선택 및 활용방법을 제시해 보았으며, 재활용 재료의 분류를 돕는 재료표시방법에 대하여 살펴보았다. 이어서 구조의 문제를 생산 및 재활용 시 조립과 분해를 용이하게 하기 위한 임시고정구조와 영구 조임 구조의 디테일 설계방법을 정리하였고, 제품완성단계에서 필요한 2차 가공방법이 재활용에 미치는 영향을 검토해 보았다. 이상과 같이 세 가지 연구방향을 토대로 재할용 설계를 위한 종합적 가이드라인을 추출하여 제시하였다.

• Proceedings of the IEEK Conference
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• 2001.09a
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• pp.113-116
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• 2001

제로트리 부호화 알고리즘 중 효율적이며 잘 알려진 SPIHT는 높은 메모리 요구로 인해 하드웨어 구현에 큰 어려움을 가지고 있다. 이 논문에서는 저 메모리 사용과 빠른 제로트리 부호화 알고리즘을 제안한다. 메모리를 줄이고 빠른 코딩을 위한 방법으로 다음 3가지를 사용한다. 첫 번째, 리프팅을 이용한 웨이블릿 변환은 기존의 필터뱅크 방식의 변환보다 저 메모리와 계산량의 감소를 가진다. 두 번째, 웨이블릿 변환된 계수들은 블럭으로 나누어져 각각 코딩된다. 여기서 블록은 제로트리 구조가 유지되는 STB(spatial tree-based block)이다. 세 번째, Wheeler 와 Pearlman이 제안한 NLS (no list SPIHT)를 이용한 부호화이다. NLS는 효율성에서 SPIHT와 거의 같으며 작고 고정된 메모리와 빠른 부호화 속도를 보여준다.

• Proceedings of the KSAR Conference
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• 2004.06a
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• pp.271-271
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• 2004

본 실험은 TGF-a를 처리하여 분화가 유도된 인간배아 줄기세포를 파킨슨 동물모델에 이식하여 숙주세포에서의 생존 및 이식효과를 검토하고자 실시하였다. TGF-a로 분화된 세포의 이식효과를 판정하고자 배양시 TGF-a처리군과 처리하지 않은 군으로 나누어 분화를 유도한 인간배아 줄기세포를 hoechst33342로 표지 하여 병변 유발과 동일한 방법으로 동측 선조체내에 4×10⁴개/2ul가 되도록 이식하고(이식 위치: AP 0.7, ML 2.0, DV3.4) 이식 후 2, 4주에서 행동학적 변화를 관찰하고 4주에 동물을 희생시켜 4% PFA를 이용하여 뇌 조직을 고정하고 뇌 조직은 40㎛ 두께로 동결 절편을 만들어 면역조직화학염색을 시행하여 신경세포로의 분화 및 TH 발현 여부를 관찰하였고 분화의 표지물질로 nestin, NF200, GFAP, TH를 사용하여 형태학적 변화를 관찰하였다. (중략)