• 제목/요약/키워드: wedge joint

검색결과 74건 처리시간 0.023초

암반 사면의 파괴 예측을 위한 불연속면 분포 특성 분석 (Analysis of Discontinuity Distribution Property to Predict Rock Slope Failure)

  • 윤운상;김정환;배기훈
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 1999년도 가을 학술발표회 논문집
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    • pp.147-152
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    • 1999
  • Distribution of fracture system is an important factor to analyse instability of jointed rock slope. In the most case of rock slopes, joint distribution properties are related to potential, shape, size and locality of slope failure. The purpose of this paper is to present an application of fracture characterization related to rock slope failure. Fracture data used in this study are collected by scanline survey. Two aspects of fracture characterization for rock slope are handled in this study First, In order to determine the potential and shape of slope failure, trace length of joints is considered as the weighting factor about collected orientation data. Second, Relationship between trace length and spacing is analysed to estimate failure location and size. The distribution of fracture system is directly influenced on wedge failure. It is effective to analyse the orientation of fractures by using weighting factors associated with the trace length of fractures rather than to analyse only that of fractures. It gives a conclusion that the wedge failure occurred along the peak of fracture density(or intensity) cycles.

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Comparison of Lower Extremity Muscle Activity during the Deep Squat Exercise Using Various Tools

  • Park, Jun Hyeon;Lee, Jong Kyung;Park, Ji Won
    • The Journal of Korean Physical Therapy
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    • 제34권2호
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    • pp.63-67
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    • 2022
  • Purpose: The purpose of this study was to investigate the effect of assistance tools such as gym balls, wedges, and straps on lower extremity muscle activity and the increase in the range of motion made possible by the use of these tools. The subjects were divided into two groups: a group capable of deep-squatting (PS) and the second finding it impossible or having difficulty in performing such squats (IS). Methods: Twenty-three subjects participated in this study. Surface electromyography was used to measure the muscle activation of the rectus femoris (RF), vastus medialis (VM), and tibialis anterior (TA) muscles during deep squats, normal squats (NS), gym ball squats (GS), wedge squats (WS), and strap squats (SS). A motion analysis system was used to measure the range of motion of the knee joint during each of these exercises. Results: There was a significant difference in the RF muscle activity between the possible squat (PS) and the impossible squat (IS) groups in the GS, and there were significant differences in the RF and TA muscle activity between the groups in the WS. Both the PS group and the IS group showed a significant difference in the TA muscle activity depending on the tool used. There were also significant differences in the range of motion of the knee joints between the intervention methods using NS and those using the tools. Conclusion: In both groups, the muscle activity of the TA muscles was lower when GS, WS, and SS were performed compared to NS. In addition, compared to NS, the range of motion of the knee joint increased when the three tools were used. This study shows that the activity of the RF, VM, and TA muscles decreased and the range of motion of the knee joint increased during deep squats for both the PS and IS groups when tools were used.

Freiberg병에서 시행한 Weil 절골술 (Weil Osteotomy for Freiberg's Disease)

  • 이화성;권순용;김동욱;정진화
    • 대한족부족관절학회지
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    • 제15권4호
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    • pp.217-222
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    • 2011
  • Purpose: The aim of this study was to evaluate the result of combined Weil and dorsal closing wedge osteotomy for Freiberg's disease. Materials and Methods: We performed combined Weil and dorsal closing wedge osteotomy of the second metatarsal under the diagnosis of Freiberg's disease in 7 patients, 7 feet (2 male and 5 female). The mean age at the time of operation was 29 years and the mean follow-up period was 31 months. Patients had no trauma history and no combined deformity of the foot. The surgical results were evaluated by VAS and weight bearing radiographs in antero-posterior and oblique projection. Results: According to Smillie staging system, there were 1 of stage II, 2 of stage III and 4 of stage IV patients. The osteotomy site was united at 8 weeks and the second metatarsal was shortened in length of average 2.8 mm. Remodeling of the metatarsal head was observed at 24 months. The mean VAS was decreased from 8.2 points preoperatively to 2.7 points at follow-up. And average range of motion of second metatarso-phalangeal joint was increased from 30o preoperatively to 45o at follow-up. There was no transfer metatarsalgia or arthritis of the metatarsal head during follow-up. Conclusion: Combined Weil and dorsal closing wedge osteotomy of the metatarsal appears to be an effective procedure for the treatment of Freiberg's disease with a view to shortening of metatarsal length and elevation of metatarsal head.

링 전단시험기를 이용한 암석절리의 잔류강도 특성에 관한 연구 (A Study on Residual Stress Characteristics for Joint of Rock in Ring Shear Tests)

  • 권준욱;김선명;윤지선
    • 한국지반공학회논문집
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    • 제16권6호
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    • pp.35-41
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    • 2000
  • Residual stress is defined as a minimum stress with a large displacement of specimens and the residual stress after peak shear stress appears with displacement volume but there is no provision to select the residual stress. In the previous study, residual stress was recorded when the change of shear load is small in the condition of the strain more than 15%. But, in this study, hyperbolic function((No Abstract.see full/text), b=experimental constant) of soil test is adapted to joint of rock and the propriety is investigated. In a landslide and landsliding of artificial slope, wedge failure of tunnel with a large displacement, tests are simulated from peak stress to residual stress for safety analysis. But now. direct shear stress and triaxial compressive tests are usually performed to find out characteristics of shear stress about joint. Although these tests get a small displacement, that data of peak stress and residual stress are used for safety analysis. In this study, we tried to determine failure criteria for joints of rock using ring shear test machine. The residual stress following shear behavior was determined by the result of ring shear test and direct shear test. In conclusion, after comparing the results of the two test, we found that cohesion(c) and internal friction angle(ø) of ring shear test are 30% and 22% respectively of those of the direct shear test.

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누두흉의 외과적 치료Metal bar 를 이용한 수술 1례 치험 (Surgical Correction of Funnel Chest by using Sulamaa`s metal strut)

  • 손동섭
    • Journal of Chest Surgery
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    • 제18권3호
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    • pp.492-496
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    • 1985
  • Two cases of surgical correction of funnel chest using metal struts were presented. The main procedures of the method were transverse submammary incision, subperichondrial resection of the deformed costal cartilages, division of the xiphisternal joint, wedge osteotomy of the sternum, freeing of the posterior surface of the sternum and stabilization by means of 2 metal struts. The struts were removed postoperative 3 and 6 months by a small incision under the local anesthesia. The results in both patients were satisfactory. This method of correction is simple, easy to perform and free of any operative risks.

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사지(四肢) 단순촬영조건(單純撮影條件)의 관전압(管電壓)에 대(對)한 연구(硏究) (A Study on Kilovoltage in Radiographic Technique Factors of the Extremities)

  • 최종학;전만진;김영일
    • 대한방사선기술학회지:방사선기술과학
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    • 제3권1호
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    • pp.29-35
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    • 1980
  • The tube voltage in radiographic technique factors of the extremities was studied to use the acryl phantom and aluminum step wedge. It was the proper tube voltage that was over 55-60kV in the finger, over 65kV in the forearm and over 75kV in the knee joint.

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편마암지역 자연사면.절취사면의 안정성 분석 사례 (Analysis of Rock Slope Stability for Natural Slope and Cut Slope of Gneiss Area in Andong, Korea)

  • 김만일;배두원;김종태;채병곤;정교철
    • 지질공학
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    • 제17권2호
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    • pp.289-297
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    • 2007
  • 매년 강우로 인해 발생되는 사면파괴는 많은 재산피해와 인명피해를 발생시키고 있다. 사면재해로부터의 피해저감을 위해 인간의 생활권과 인접한 사면에 대한 지속적인 관리를 통해 이들의 안정성 검토와 보강 대책이 요구된다. 연구지역은 편마암으로 이루어진 암반사면으로써 단층작용으로 인해 대규모 절리군이 형성되어 있는 풍화암 내지 연암의 풍화 특성을 보여준다. 조사사면을 자연사면과 절취사면으로 구분하여 현장자료를 검토한 결과, 자연사면에서는 주 절리군이 형성된 4개 지점에서 평면파괴와 쐐기파괴 가능성이 우세하였으며, 절취사면의 경우 8개 지점에서 쐐기파괴 발생 가능성이 높게 나타났다. 또한 SLIDE 2D에 적용해 이들 사면의 최소안전율에 대한 수치해석 결과에서는 자연사면보다 절취사면의 안정성이 비교적 취약한 것으로 분석되었다.

자가 골연골 이식술을 이용한 Freiberg 병의 치료(1예 보고) (Autogenous Osteochondral Graft for Freiberg's Disease (A Case Report))

  • 김형년;엄상화;서동현;박용욱
    • 대한족부족관절학회지
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    • 제13권2호
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    • pp.223-226
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    • 2009
  • Freiberg disease is a osteochondrosis of the lesser metatarsal heads. Various surgical treatment have been recommanded including joint debridement and metatarsal head reshaping, metatarsal dorsal wedge osteotomy, metatarsal head excision and joint arthroplasty. Autogenous osteochondral graft for the treatment of Freiberg disease is an effective restorative procedure that provides early range of motion exercise, weight bearing, and reduces other morbidity. We report a case of late stage Freiberg disease treated with arthrotomy, removal of loose body and autogenous osteochondral graft.

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대학 골프 선수의 Pitching wedge 스윙동작의 운동학적 특성 분석 (Kinematical Analysis of Pitching wedge swing motion in University Golfer)

  • 백진호;윤동섭;김재필
    • 한국운동역학회지
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    • 제13권3호
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    • pp.133-149
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    • 2003
  • The purposes of present study were to determine the major check-points of golf swing from the review of previous studies, and to suggest additional information on the teaching theory of golf. The golf swing motion of 6 male and female elite university golf players were filmed with 16mm Locam II high speed cameras at the speed of 200f/s, and variables such as time, displacement, angle, velocity were calculated and analyzed by 3D Cinematography using DLT method. The results were: 1. Differences were shown in the ratio of weight distribution on the feet, cocking angle, take-back velocity, club-head velocity at impact depending upon the physical characteristics and club used for swing. 2. Time for the down-swing and impact were $0.27{\sim}0.29s$ in men and $0.29{\sim}0.32s$ in women, which was 1/3 of the time for the back-swing. Women showed longer total swing time than men because of longer time in back-swing, follow-through and finish. 3. Men showed larger range of motion in shoulder and knee joints than women, on the other hand women showed larger range of motion in hip joint than men. 4. Cocking motion and right elbow flexion were occurred at the top of back-swing and cocking release was occurred at the moment of impact. Maximum rotations of shoulder and hip joints were found between the top of back-swing and down-swing phase. 5. Women showed lower back-swing velocity than men, and men showed higher club velocity(men: $38.2{\sim}38.6m/s$, women: $35.1{\sim}36.4m/s$) than women.

Short-Term Results of Hybrid Closed-Wedge High Tibial Osteotomy: A Case Series with a Minimum 3-Year Follow-up

  • Saito, Hidetomo;Saito, Kimio;Shimada, Yoichi;Yamamura, Toshiaki;Yamada, Shin;Sato, Takahiro;Nozaka, Koji;Kijima, Hiroaki;Miyakoshi, Naohisa
    • Knee surgery & related research
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    • 제30권4호
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    • pp.293-302
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    • 2018
  • Purpose: High tibial valgus osteotomy (HTO) is a well-established surgical procedure for patients with medial compartment osteoarthritis (OA) of the knee. The hybrid closed-wedge HTO (CWHTO) procedure permits extensive correction in patients with severe deformities or patellofemoral joint OA. The aim of this study was to report the short-term results in a consecutive series of patients treated with hybrid CWHTO. Materials and Methods: We retrospectively evaluated the clinical outcomes and radiographic parameters in 29 consecutive knees that underwent hybrid CWTHO to correct medial compartment OA at an average follow-up of 52.6 months. Clinical outcomes were assessed using the Lysholm score and knee scoring system of the Japanese Orthopedic Association (JOA). The Kellgren-Lawrence grading system and pre- and postoperative mechanical axis (MA), femorotibial angle (FTA), posterior tibial slope, and patella height were assessed. Results: The FTA and MA significantly changed from $180.7^{\circ}$ to $170.4^{\circ}$ and from $22.0^{\circ}$ to $60.2^{\circ}$, respectively. No significant differences were observed between the mean pre- and postoperative posterior tibial slope, Insall-Salvati ratio, or Caton-Deschamps index. The postoperative JOA and Lysholm scores significantly improved from 76.7 to 95.8 and from 58.8 to 90.2, respectively. Conclusions: Satisfactory outcomes can be achieved with hybrid CWHTO in patients with medial OA.