• Geophysics and Geophysical Exploration
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• v.14 no.2
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• pp.127-132
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• 2011

We acquired and interpreted more than 650 km of high-resolution seismic reflection profiles in the Hupo Basin, offshore east coast of Korea at $37^{\circ}N$ in the East Sea (Japan Sea) to image shallow and basement deformation. The seismic profiles reveal that the main depocenter of the Hupo Basin in the study area is bounded by the large offset Hupo Fault on the east and an antithetic fault on the west; however, the antithetic fault is much smaller both in horizontal extension and in vertical displacement than the Hupo Fault. Sediment infill in the Hupo Basin consists of syn-rift (late Oligocene. early Miocene) and post-rift (middle Miocene.Holocene) units. The Hupo Fault and other faults newly defined in the Hupo Basin strike dominantly north and show a sense of normal displacement. Considering that the East Sea has been subjected to compression since the middle Miocene, we interpret that these normal faults were created during continental rifting in late Oligocene to early Miocene times. We suggest that the current ENE direction of maximum principal compressive stress observed in and around the Korean peninsula associated with the motion of the Amurian Plate induces the faults in the Hupo Basin to have reverse and right-lateral, strike-slip motion, when reactivated. A recent earthquake positioned on the Hupo Fault indicates that in the study area and possibly further in the eastern Korean margin, earthquakes would occur on the faults created during continental rifting in the Tertiary.

• Journal of the Korean Arthroscopy Society
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• v.7 no.2
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• pp.220-225
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• 2003

The meniscal cyst of knee joint is a rare disease, and the discoid meniscal cyst has not been reported in Korea. We report 3 cases of the discoid meniscal cyst confirmed by MRI and arthroscopy. In physical examination, all cases have tenderness of the knee joint. One has palpable mass of knee joint and the other one has limitation of knee motion with knee flexion contracture of 10 degrees and positive McMurray test at external rotation of the knee. All cases are complete discoid meniscus, which are, one medial discoid meniscus and two lateral discoid meniscus through MRI. We confirmed horizontal tear of meniscus in all cases and the location of meniscal cysts are anterior hem of meniscus in one and body of meniscus in two. We could get excellent results in all 3 cases that return to normal knee range of motion.

• Journal of Korean Orthopaedic Sports Medicine
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• v.2 no.2
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• pp.77-81
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• 2003

Purpose: The biomechanics and kinematics of knee joint were reviewed in this article. And then the common sports injuries were presented. Anatomy and Kinetics: None of the pairs of bearing surfaces in the knee joint is exactly congruent This allows the knee six degrees of freedom of motion. Tibiofemoral Kinematics: In flexion and extension, the axis of motion is not perpendicular to the medial-lateral plane of the joint, nor is it perpendicular to the axis of longitudinal rotation. This results in coupled varus angulation and internal rotation with flexion and in valgus angulation and external rotation with extension. Patellofemoral Articulation: Loads across the patellofemoral joint are indirectly related to the angle of knee flexion and directly related to the force generated within the quadriceps mechanism. Fractures of the Patella: Nonoperative treatment is indicated if the extensor mechanism is intact and if displacement of fragment is minimal. The specific type of internal fixation depends on the fracture pattern. It is important to repair retinaculum. Acute and Recurrent Patellar Instability: The degree of dysplasia and the extent of the instability play a large part in determining the success of nonoperative treatment. Patients who experience recurrent dislocations and patients with major anatomic variations require surgery to minimize their instability. Sports Injuries in School-age Atheletes: Patellar pain in young athletes groups a number of conditions, including Idiopathic Adolescent Anterior Knee Pain, Osgood- Schlatter Disease, and Sinding-Larsen-Johansson Disease.

• Journal of Korean Orthopaedic Sports Medicine
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• v.4 no.2
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• pp.116-121
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• 2005

Purpose: Isolated capitellar fractures are rare, intra-articular fractures requiring an aggressive management regimen. Review the outcome after open reduction and internal fixation of the capitellar fractures. Materials and Methods: From 1998 to 2004, 4 patients with displaced fractures of the humeral capitellum were treated by open reduction and internal fixation of the capitellar fragments with cannulated screws. By use of the criteria of Bryan and Morrey et al, there were 3 type I fractures, 1 type III fracture. A lateral approach was used. The elbows were immobilized postoperatively for 4 to 28 days We evaluated the range of motion, stability, and pain using the criteria of Mayo score. Results: The follow-up period ranged from 12 to 36 months (mean, 15months). Three patients had a stable, pain-free elbow with good range of motion at follow-up. One patient with a neglected capitellar fracture have felxtion cpontracture of 40 degrees with 100 degrees of further felxion(total arc: 60) due to poor compliance to the postoperative rehabilitation. All fractures healed, and there was no evidence of avascular necrosis or degenerative change. Conclusion: Capitellar fractures, rare in case, gave a good result after open reduction and simple internal fixation with cannulated screws without any problem.

• Korean Journal of Applied Biomechanics
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• v.19 no.3
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• pp.467-479
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• 2009

The purpose of this study was to present the quantitative data which riders can utilize teaching field by comparison analysis of kinematics according to skill level of rider during 2 strides rising trot with the JeJu's-Horse. Participated subjects was consisted of total 10 riders(unskilled: n=5, skilled: n=5). The method of experiment & analysis was based on 3D cinematography. Variables were consisted of temporal, linear & angular kinematics by each event & phase. The skilled assigned more ratio of elapsed time in air than support phase, had the less range of motion in up-down direction and more consistent velocity in lateral & forward direction and performed periodic up-down movement with alignment in vertical direction according to elapsing of phases. The skilled more flexed at elbow and extended backwardly according to elapsing of phases, while more flexed forwardly at hip & knee and plantarflexion at ankle. The skilled postured backward extension but the unskilled do forward flexion. That is, It was considered that the unskilled continued more unstable posture than the skilled during 2 strides in rising trot.

• Radiation Oncology Journal
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• v.15 no.4
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• pp.387-392
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• 1997

Purpose : To quantify the movement of lung Parenchyma for ICRU 50 Planning Target Volume (PTV) delineation of the lung region. Materials and Method : Fluoroscopic observations and measurements are Performed on 10 patients with chest region cancer who have normal putmonary functions We have divided the lung region into 12 parts for the right lung, 10 parts for the left lung and four to five Points of lung parenchyma were selected for anatomical analysis Points, Fluoroscopic images are sent to a computer and then movements are measured. Results : Both lowe lobes showed the longest longitudinal movements because of breathing (average 14.1mm, maximum 22.1mm), while anteroposterior displacement showed the smallest value. Lateral movements of the lung parenchyma averaged 6.6mm, and the maximum value was 9.1mm, (both hilar regions showed maximum values because of cardiac motion) Conclusion : We could quantify the lung movements by measuring parenchyma displacements. The movements of both upper lobes were less than those of the middle and upper lobes in longitudinal and transverse movements. Optimal margins can be selected for PTV delineation using these results.

• Clinics in Shoulder and Elbow
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• v.9 no.1
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• pp.50-59
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• 2006

Purpose: The nonoperative outcome of elbow dislocations with associated radial head and coronoid fractures are often unsatisfactory because of chronic instability and stiffness from proloned immobilization, Therefore we managed these injuries with well programed surgical appproaches. Method: Ten patients with this injury were evaluated retrospectively from May 1998 to June 2004 after a minimum of 12 months. These injuries include elbow dislocation and associated fractures of both the radial head and the coronoid process. All ten patients were treated by one clinic operatively with similar scheduled surgical methods which started on the lateral side and terminated on the medial side of the elbow. Radial head and neck fractures were classified Mason types, as two and three types respectively with six and four cases and six cases were fixated. Coronoid process were fixated with screws anteroposterior directly or anchor suture in all cases, each type was classified one, two and three. where were three type one, four type two, and three type three were according to Regan and Morrey classification. Results: The outcome was three resulting in excellent, four good, two normaland and the remaining case was one poor according to the Mayo Elbow Performance score. At a terminal follow up, the range of motion of the elbow averaged flection contracture, $6^{\circ}(0{\sim}20^{\circ})$ and further flection, $129^{\circ}(115{\sim}140^{\circ})$. Two patients had complications requiring additional care. One, displaced coronoid process which was repaired with capsule and the other patient experienced, palsy of ulnar nerve and contracted elbow joint. Conclusions: Usage of early operation as the minimum injury of medial ligaments complex and the rigid fixation of fractures to prompt motion with our scheduled management for elbow dislocations with associated radial head and coracoid fractures provided excellent results.

• Journal of the Society of Naval Architects of Korea
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• v.39 no.3
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• pp.57-63
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• 2002

This paper describes a control algorithm for the buffer of a deep-sea mining system, in which the buffer is connected to a long slender pipe and then to a surface ship on one end, and to a collector on sea floor through a flexible hose on the other end. A mathematical modeling is established for designing the controller for buffer thrusters, in which the dynamic response of the long pipe is taken into account based on the mode superposition method. The fluid loading acting on the pipe is estimated by using Morison's formula. For simplicity, the surface ship is assumed to be kept stationary, the reaction from the flexible hose is ignored and only the lateral motions are considered. In order to guide the buffer to react only to the low-frequency motion of the surface vessel, the FIR digital filter is introduced to a PID-based controller It can be shown numerically that the high frequency component of the ship's motion can be effectively filtered out by using the FIR low pass filter.

• Physical Therapy Korea
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• v.25 no.3
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• pp.19-26
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• 2018

Background: Genu varum is also known as bow leg. It is a deformity wherein there is lateral bowing of the legs at the knee. it does give rise to pain, and persistent bowing can often give rise to discomfort in knees, hips and ankles. Objects: This study investigated the effect of narrow squats on the knee joint during a gait and distance between the knees of person with genu varum. Methods: This study analyzed 23 patient with genu varum that grade III, 12 narrow squat group and 11 genenal squat group in motion analysis laboratory. The subjects of experiment took gait before and after intervention, the range of joint motion, moment of knee joint adduction, power, distance of the knees were measured. And in order to make an analysis between groups, an paiered t-test and independent t-test was carried out. For statistical significance testing, it was decided that significance level ${\alpha}$ be .05. Results: It was shown that the group of narrow squat exercise significantly decreased in distance of knees (p<.05),In moment of adduction of knee joint, it was shown to significantly decrease in two groups (p<.05), was significantly decreased in adduction, abduction, and rotation (p<.05). In relation of peak-knee adduction moment and valgus angle, there was significant decrease in narrow squat group (p<.05). Conclusion: When the above result of study were examined, a narrow squat exercise given to the genu varum patients significantly decreased the distance between the knees, range of knee adduction and abduction, knee adduction moment, knee power. And stability gains through the decrease of excursion of knee medial part be effective for the correction of genu varum deformation.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.33 no.2
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• pp.121-128
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• 2020

The purpose of this study is to investigate the distribution patterns of displacement and acceleration fields in a nonlinear soil ground based on the interaction of high-speed train, wheel, rail, and ground. For this purpose, a high-speed train in motion was modeled as the actual wheel, and the vertical contact of wheel and rail and the lateral contact, caused by meandering motion, were simulated; this simulation was based on the moving mass analysis. The soil ground part was given the nonlinear behavior of the upper ground part by using the modified the Drucker-Prager model, and the changes in displacement and acceleration were compared with the behavior of the elastic and inelastic grounds. Using this analysis, the displacement and acceleration ranges close to the actual ground behavior were addressed. Additionally, the von-Mises stress and equivalent plastic strain at the ground were examined. Further, the equivalent plastic and total volumetric strains at each failure surface were examined. The variation in stresses, such as vertical stress, transverse pressure, and longitudinal restraint pressure of wheel-rail contact, with the time history was investigated using moving mass. In the case of nonlinear ground model, the displacement difference obtained based on the train travel is not large when compared to that of the elastic ground model, while the acceleration is caused to generate a large decrease.