• 대한기계학회:학술대회논문집
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• 대한기계학회 2001년도 춘계학술대회논문집A
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• pp.636-643
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• 2001

Interference between the crossover leg of the reactor coolant system (RCS) and the pipe whip restraints (PWR) has brought a degradation issue of the integrity of the Reactor Coolant System in Westinghouse type nuclear power plants (NPPs) of Korea. According to the gap Inspect ion carried out during planned overhaul (Year 2000), interference between the crossover leg and the PWR was found in each RCS loop. This plant has had the high vibration problem on the RC pump 'B'. The reason for the high vibration in the RC pump 'B' had been massively surveyed and it was found that the crossover leg of RCS contacted with the PWR in hot condition. Since the contact between the crossover leg and the PWR changes the dynamic characteristics of the piping system for the RCS, this is considered as one reason for the high vibration. And a possibility of overstress on the crossover leg due to the contact with the PWR should be evaluated. Through performing RCS integrity analyses, subsequent actions were initiated to increase the gap between those parts. As the results of the appropriate separation between two parts, it was reported that there was no unusual noise or vibration during plant heat-up. In this paper, the evaluations for the gap between the crossover leg and the PWR and the structural integrity due to loop binding is described.

• 한국원자력학회:학술대회논문집
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• 한국원자력학회 2001년도 춘계학술발표회요약집
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• pp.112.1-112
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• 2001

• Journal of Chest Surgery
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• 제22권2호
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• pp.337-341
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• 1989

A 40-year-old male developed the swelling of the right leg one month after trauma on cycling. Conservative measures to relieve the swelling of the right leg for three months were failed. Venogram showed complete obstruction of the right common iliac vein. Crossover bypass [Palmas operation] with great saphenous vein graft for relief of venous stasis of the right leg was performed. Postoperatively, the swelling of the right leg was subsided and able to walk without edema of the right leg.

• Journal of Chest Surgery
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• 제43권5호
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• pp.534-537
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• 2010

5세 때에 교통사고 후 지혈목적으로 대퇴정맥 결찰을 받은 26세 남자 환자가 입원 5일 전 축구하다 생긴 좌측 하지의 정맥궤양에서 나타난 출혈을 주소로 입원하였다. 환자는 좌측 하지에 하지 정맥류의 발생과 정체성 피부염과 정맥 궤양이 있었다. 좌측 대퇴정맥 혈류를 우측 대퇴정맥으로 환류시키려고 우측 대복재정맥을 이용하여 동정맥루가 있는 우회로 조성술을 시행하였다. 우회로의 원활한 개통을 위해 만든 동정맥루는 처음 수술 6주 후에 폐쇄하였다. 환자는 수술 후 6개월 간 좌측 하지 둘레가 비교적 일정하게 유지되고 있다. 이와 같이 만성 대퇴정맥 결찰 환자에 대한 정맥 crossover 우회로 조성술 1예를 치험하였기에 보고하는 바이다.

• Nuclear Engineering and Technology
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• 제50권6호
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• pp.829-841
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• 2018

An experiment was conducted for the OECD/NEA ROSA-2 Project using the large-scale test facility (LSTF), which simulated a 17% hot leg intermediate-break loss-of-coolant accident in a pressurized water reactor (PWR). In the LSTF test, core uncovery started simultaneously with liquid level drop in crossover leg downflow-side before loop seal clearing, and water remaining occurred on the upper core plate in the upper plenum. Results of the uncertainty analysis with RELAP5/MOD3.3 code clarified the influences of the combination of multiple uncertain parameters on peak cladding temperature within the defined uncertain ranges. For studying the scaling problems to extrapolate thermal-hydraulic phenomena observed in scaled-down facilities, an experiment was performed for the OECD/NEA PKL-3 Project with the Primarkreislaufe Versuchsanlage (PKL), as a counterpart to a previous LSTF test. The LSTF test simulated a PWR 1% hot leg small-break loss-of-coolant accident with steam generator secondary-side depressurization as an accident management measure and nitrogen gas inflow. Some discrepancies appeared between the LSTF and PKL test results for the primary pressure, the core collapsed liquid level, and the cladding surface temperature probably due to effects of differences between the LSTF and the PKL in configuration, geometry, and volumetric size.

• Journal of Chest Surgery
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• 제36권5호
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• pp.367-370
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• 2003

양측 하지의 냉감과 우측 족지의 피부변색을 주소로 내원한 62세 남자환자가 혈관조영상 우측 외장골동맥과 좌측 총장골동맥의 폐쇄소견을 보였다. 환자는 전반적인 전신상태가 좋지 않아 확장성 해부학적외 동맥재건슬을 시행하였다. 우측 쇄골하동맥에서 우측 슬와동맥까지는 8 mm PTFE와 6 mm PTFE를 이용하여 문합하였다. 우측 서혜부의 8 mm PTFE와 좌측 총대퇴동맥을 골반 위에 다른 8 mm PTFE를 거치하여 교차문합하였다. 이후 환자는 별다른 합병증 없이 퇴원하여 현재 외래 추적 중으로 우측 하지의 족지에 피부변색은 없어져 완전히 정상화되었으며 통증 또한 사라졌다. 쇄골하동맥-슬개동맥-교차-대퇴동맥-PTFE-우회술이라는 확장성 해부외 동맥 재건술을 치험하였기에 보고하는 바이다.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2003년도 ICCAS
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• pp.215-219
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• 2003

In this paper, we generate a trajectory minimized the energy gait of a biped robot for walking a staircase using genetic algorithms and apply to the computed torque controller for the stable dynamic biped locomotion. In the saggital plane, a 6 degree of freedom biped robot that model consists of seven links is used. In order to minimize the total energy efficiency, the Real-Coded Genetic Algorithm (RCGA) is used. Operators of genetic algorithms are composed of a reproduction, crossover and mutation. In order to approximate the walking gait, the each joint angle is defined as a 4-th order polynomial of which coefficients are chromosomes. Constraints are divided into equality and inequality. Firstly, equality constraints consist of position conditions at the end of stride period and each joint angle and angular velocity condition for periodic walking. On the other hand, inequality constraints include the knee joint conditions, the zero moment point conditions for the x-direction and the tip conditions of swing leg during the period of a stride for walking a staircase.

• 한국정밀공학회지
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• 제23권4호
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• pp.75-82
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• 2006

In this paper, we propose an optimal trajectory for biped robots to move up-and-down stairs using a genetic algorithm and a computed-torque control for biped robots to be dynamically stable. First, a Real-Coded Genetic Algorithm (RCGA) which of operators are composed of reproduction, crossover and mutation is used to minimize the total energy. Constraints are divided into equalities and inequalities: Equality constraints consist of a position condition at the start and end of a step period and repeatability conditions related to each joint angle and angular velocity. Inequality constraints include collision avoidance conditions of a swing leg at the face and edge of a stair, knee joint conditions with respect to the avoidance of the kinematic singularity, and the zero moment point condition with respect to the stability into the going direction. In order to approximate a gait, each joint angle trajectory is defined as a 4-th order polynomial of which coefficients are chromosomes. The effectiveness of the proposed optimal trajectory is shown in computer simulations with a 6-dof biped robot that consists of seven links in the sagittal plane. The trajectory is more efficient than that generated by the modified GCIPM. And various trajectories generated by the proposed GA method are analyzed in a viewpoint of the consumption energy: walking on even ground, ascending stairs, and descending stairs.

• 대한통합의학회지
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• 제9권3호
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• pp.165-173
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• 2021

Purpose : Myofascial decompression is frequently mentioned as a method applied to cupping. The purpose of this study is to evaluate and compare active range of motion (AROM), muscle strength, and functional movement by applying myofascial decompression to the hamstrings. Methods : This study evaluated AROM, muscle strength, and functional movement by applying active movement myofascial decompression and static myofascial decompression to the dominant leg, respectively, in a crossover design conducted with normal adults (n=21) in their average 20s enrolled at G University in G city, Gyeongsangbuk-do. Active movement myofascial decompression was implemented for five minutes at a rate of 100 bpm to make the beats in flexion and extension respectively. Static myofascial decompression was only performed for five minutes while at rest. All of these interventions were performed at a cupping depth of two mm. After a one-week washout period, static was applied again to compare the same dependent variables. Results : Regarding AROM and muscle strength, both groups showed significant differences in the before and after results (p<.05). However, in the Functional Reach Aspect and Single Leg Hop test, the active movement myofascial decompression group showed better results. There was no statistical difference between the Active movement myofascial decompression group and Static myofascial decompression group in any dependent variable (p<.05). Conclusion : As a result of this experiment, both active movement myofascial decompression and static myofascial decompression had a positive effect on dependent variable. Therefore this study is meaningful in that it is easier and simpler to see the effect on flexibility, muscle strength, and functional movement just by implementing movement myofascial decompression.

• 대한물리의학회지
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• 제12권3호
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• pp.23-32
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• 2017

PURPOSE: Flexibility and range of motion are very important factors in sports performance, rehabilitation, and musculoskeletal pain. The purpose of this study was to measure the effects of cupping therapy on flexibility, muscle activity, and pain threshold of hamstring muscle compared to passive stretching in healthy subjects. METHODS: Thirty healthy subjects were randomly assigned in a crossover design to cupping therapy and passive stretching. Subjects were tested to compare their effects according to the intervention such as Passive range of motion (PROM) (straight leg raising) and active range of motion (AROM). And algometer (pain) testing and MVC assessment using EMG were performed as dependent variables. RESULTS: The cupping therapy group and passive stretching group showed significant differences in all variables including PROM (p=.00, p=.00), AROM (p=.00, p=.03), Pain Threshold (p=.03, p=.08), Semitendinosus MVC (p=.01, p=.00), and Biceps femoris MVC (p=.01, p=.16). There were no significant differences between the two groups in all variables. CONCLUSION: These findings of this study suggested that cupping therapy has as much positive effect on flexibility, pain threshold, and muscle contraction as passive stretching. Also, it is more convenient and easier to work on patients than passive stretching. Therefore, cupping therapy should be considered as another option to treat range of motion, pain, and muscle activity in the clinical field.