• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2004년도 추계학술대회 논문집
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• pp.1180-1185
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• 2004

The purpose of this study is to develop a Multi-joint rehabilitation system (CMRS : C&R Lab. Multi-joint Rehabilitation System). This study presents the mechanism of rehabilitation system that enables rehabilitation of multi-joint with kinematical analysis for joints of human body. Also, the relative positioning between human subjects and the head part to rehabilitate for the mechanism is based on robotics and anatomy. This study was verified with simulations. Finally, Automation of positioning was realized. Rehabilitation exercises in passive mode were enabled with the results.

• Structural Engineering and Mechanics
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• 제29권1호
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• pp.17-35
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• 2008

Neglecting the real joint behaviour in frame analysis may result in unrealistic predictions of the response and reliability of steel frames. The reliability of the prediction of main joint properties according to the component method (Eurocode 3-Part 1.8) still remains open to further investigation. The first step toward the solution is to compare the theoretical expressions given in EN 1993-1-8 and the experimental results. With that goal in mind six nominally the same, but really different specimens of welded beam-to-column joints subjected to static load were tested. The specimens present a combination of nominally identical structural elements produced in different European mills. This paper provides these tests, as well as their detailed evaulation and interpretation. All three joint structural properties (rotational stiffness, moment resistance and rotation capacity) have been considered. Four models for determining the plastic resistance out of experimental Mj-${\phi}$ curves have been applied. The results that have been discussed in detail, point to the fact that EN 1993-1-8 underestimates the real structural properties of the tested type of joint, as well as to the conclusion that detailed research of this problem needs to be conducted using the probabilistic reliability methods.

• 한국농공학회지
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• 제43권6호
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• pp.113-119
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• 2001

Experiments on the yield strength of pipe connectors made of metal wire, joint pins, pole pipes, multi span insertion joints, and T-clamp joints used in pipe houses were conducted. The strength of connections of a pipe connector made of metal wire was adequate but it had a big difference according to loading direction. Therefore as it is installed, its direction should be taken into consideration. The collapse load of pipes connected with a joint pin was lower than that of single pipes. In the part of frame member at which the great bending moment occurs, the use of joint pin should be avoided. Also experimental results showed that pole pipes for use in a part of frame buried under the ground were safe, and the strength of multi span insertion joints should be increased. The resistant moment of T-clamp was about 13.7% of a single pipe. In case that the external forces acting on left and right rafter are different. a unsymmetrical rotational force is produced at the multi span joint. If it is expected that the actual bending moment on the multi span joint is larger than resistant moment of T-clamp, a reinforcement to safely resist the rotational force is required.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2006년도 춘계학술대회 논문집
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• pp.399-402
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• 2006

The outer race of CV(constant velocity) joint is an important load-supporting automotive part, which transmits torque between the transmission gear box and driving wheel. The outer race is difficult to forge because its shape is very complicated and the required dimensional tolerances are very small. Traditional warm and cold forging methods have their own limitations to produce such a complex shaped part; warm forging requires complex system with relatively higher manufacturing cost, while cold forging is not applicable to materials with limited formability. Therefore, multistage forging may be advantageous to produce complex shaped parts. In order to build a multistage forging system, it is necessary to characterize mechanical properties in response to system design parameters such as temperature, forging speed and reduction. For the analysis of formability of multistage forging process, finite element method(FEM) has been used for the process analysis. As a model case, a constant velocity (CV) joint forging process is analyzed by FEM, since CV joint has a complex shape and also its required dimensional tolerances are very tight. The data acquired by FEM is compared with operational forging data obtained from an industrial production line. Based on this comparative analysis, multistage forging process for CV joints is proposed.

• 대한족부족관절학회지
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• 제21권3호
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• pp.108-112
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• 2017

The midtarsal joint is composed of the talonavicular and calcaneocuboid joints. It is also known as the Chopart joint. Midtarsal joint fracture and dislocation are relatively rare and frequently missed or misdiagnosed. A proper understanding about the anatomy of the midtarsal joint is an essential part in comprehending the mechanism of injury and rationale for treatment. Anatomical reduction of midtarsal joint with correction of the column in length and shape are important; however, it is technically challenging and may require open procedure. Herein, we described a case of initial open reduction and internal fixation for midtarsal joint fracture and dislocation with a brief literature review.

• Journal of Electrical Engineering and information Science
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• 제2권6호
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• pp.90-94
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• 1997

The joints between the superconducting wires are inevitably needed from the requirement of a high magnetic stability with respect to time in the superconducting MRI magnet. In this study, a new superconducting joint using Cu/Nb-Ti sleeve has been tried on the MRI type Nb-Ti superconducting wires. The transformer induction type apparatus was made and applied to measure the joint resistance. A very low joint resistance of 10\ulcorner $\Omega$ could be successfully obtained from this joint method. It was confirmed that the initial rapid current decay occurs before the very stable current decay due to only superconducting joint. Some unstable part in the joint like exposed filaments causes the initial induced current to lower and influence on the increase of the joint resistance.

• 기본간호학회지
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• 제10권1호
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• pp.30-36
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• 2003

Purpose: The strength of hand grip, low back muscles and knee joint muscles were measured and then compared to the bone mineral density (BMD) of each forearm bones (including ulna and radius), lumbar spine, and femur in young women in order to identify the relationship between muscle strength and bone mineral density. Method: The BMD was measured with a Dual Energy X-ray Absorptiometry and muscle strength was measured with a handgrip dynamometer and a Cybex Norm. Data were analyzed with frequencies, percentages, means, and Pearson correlation coefficients. Result: 1) Higher grip strength correlated positively with higher BMD in the forearm (r=.246, p=.007), higher low back extensor strength with higher BMD in the femur (neck, trochanter and Ward's triangle)($r=.323{\sim}.226$, $p=.003{\sim}.043$) and higher strength in the knee joint extensor with higher BMD in the lumbar spine (r=.227, p=.041), femur neck, and femur trochanter significantly ($r=.295{\sim}.226$, $p=.007{\sim}.043$). There was no significant correlation between the strength of low back extensors and BMD in the lumbar spine, now with strength of knee joint flexor and the BMD in the femur. 2) The muscle strength of each part of the body had significant positive correlations to each other part ($r=.255{\sim}.728$ $p=.021{\sim}.000$) Conclusion: The results of this study showed that with the development of a muscle there was an increased BMD of the corresponding part, and the BMD of each part was influenced by adjacent muscles. To promote the health of bones, it is important to strengthen the muscles of related bones, based on balanced development of all muscles.

• 대한물리의학회지
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• 제9권4호
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• pp.347-354
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• 2014

PURPOSE: This study was to examine changes in muscle activity of lower extremity shoes sole form (high heels, shoes with curved out sole, house shoes). METHODS: The subjects of this study were 12 women in their twenties. They put three kinds of shoes (high heels, shoes with curved out sole, house shoes) and walked 5m. The muscles activities of lower extremity muscles (rectus femoris, vastus medialis, tibialis anterior, gastrocnemius medial part) were measured using a wireless electromyogram (EMG). Rectus femoris was attached to 1/2 position at the distance between ASIS and knee bone and vastus medials was attached to 2cm from upper inside of knee bone. Tibialis anterior was attached to 75% position above line connecting knee joint and ankle joint and gastrocnemius medial part was attached to 3 5% position above knee joint and ankle. RESULTS: It was found that there were significant differences in changes of muscles activities of lower extremity muscles (rectus femoris, vastus medialis, tibialis anterior, gastrocnemius medial part) on shoes sole forms (p<.05). All lower extremity muscles were showed high muscles activities, when high heels wear (p<.05). Wearing shoes with curved out sole was showed high muscle activity of tibialis anterior and lower muscle activity of gastrocnemius medial part compared with wearing house shoes (p<.05). CONCLUSION: Shoes sole form should be considered when patients with knee and ankle joint problems choose shoes because muscles were showed different activities according to shoes sole forms.

• 재활복지공학회논문지
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• 제8권3호
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• pp.177-185
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• 2014

본 연구에서는 하지마비 장애인의 족하수 방지를 위하여 족배굴곡 보조를 위한 외골격 보조기를 개발하였다. 본 보조기는 인공 근육형 공압 액추에이터를 이용한 동력 전달부, 동력부의 고정을 위한 무릎 관절 착용부 및 보행 신호 검출을 위한 발목 관절 착용부로 구성되었다. 보조기는 무릎 관절 착용부와 발목 관절 착용부에 고정되어 족배굴곡 토크를 발생시켰으며, 발바닥 압력센서를 통해 사용자의 보행 단계를 검출하고, 족배굴곡 보조 타이밍을 감지하도록 하였다. 보행에 이상이 없는 건강한 65세 이상 고령자 7명과 20대 성인 10명을 대상으로 외골격 보조기의 족배굴곡 보조에 대한 성능을 확인한 결과, 인공 근육형 공압 액추에이터의 보조 시 전경골근의 근활성이 감소하는 결과가 나타났다. 향후 연구에서는 하지마비 환자를 대상으로 외골격 보조기의 효과를 검증할 것이다.

• 한국건축시공학회지
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• 제10권3호
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• pp.129-136
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• 2010

지붕 개폐형태의 대공간 막 구조물은 멀티미디어적인 요소 및 전천후 공간을 활용할 수 있지만, 다수의 연결 조인트에 의해 구조물이 형성되므로 누수에 취약한 문제점이 있다. 특히 개폐식 지붕 맞댐부위의 우수차단 시스템은 우수의 직접적인 유입을 차단하는 역할을 하고 있으므로 바람을 동반한 강우환경에서도 수밀성능이 요구된다. 따라서 상기의 환경 조건을 부여한 수밀성 실험을 통하여 우수차단 시스템의 디테일에 대한 수밀성능을 평가하고자 한다. 실험 결과, 모든 실험체에서 누수가 발생하였으며, 우수의 유입경로는 동일한 것으로 확인되었다. 특히, 바람에 의하여 물입자들이 구조물 내부로 들이치는 현상이 주원인이므로 이를 보완한 새로운 우수차단 시스템의 디테일이 요구된다. 이 연구를 통해 강우 환경과 바람 환경을 동시에 부여하였을 때 발생될 수 있는 우수 침입 경로를 확인하였으며, 수밀 성능 확보 유무가 사전에 검토되어 져야함을 알 수 있었다. 또한, 디테일을 사전에 작성하여 모형 수밀성 시험을 반드시 시행한 후 그 결과에 따라 설계 디테일의 변경, 개선, 보완시공을 하여야 할 것이다.