• 한국수자원학회논문집
• /
• 제40권2호
• /
• pp.101-112
• /
• 2007

본 연구에서는 댐군을 연계운영할 경우 발생하는 효과를 이수측면에서 평가할 수 있는 방법을 개발하여 한강수계 댐군 운영 실적의 평가에 적용하였다. 개발된 평가방법에서는 용수공급과 유황개선 부분에서 연계운영의 효과를 평가하기 위하여 평가지점에서 필요수량에 대한 충족률과 유황안정도를 평가지표로 사용하였다 발전 부분에서 연계운영의 효과는 댐군에 의해 생산된 총발전량을 평가지표로 사용하였다. 실제 운영실적은 공칭공급량을 공급하는 단독운영과 최적화 모형에 의한 평가지표들과 비교하여 평가되었다. 한강수계의 2001년부터 2004년까지의 실제 연계운영 실적을 단독운영과 최적화 모형의 결과와 각 연도별로 비교해 보면, 용수공급 측면에서 필요수량 충족률은 단독운영은 $94.36{\sim}99.68%$, 실제운영은 $97.16{\sim}99.90%$, 최적화 모형은 4개년 모두 100.0 %를 나타냈다. 댐 운영 방법별로 하상계수와 유황계수를 사용하여 유황안정도를 평가해 보면, 유황이 단독운영 보다 실제운영과 최적화 모형이 더 안정적인 결과를 나타냈다. 실제 총발전량을 다른 운영방법의 결과와 비교해 보면, 최적화 모형은 실제 총발전량 보다 $-3.47{\sim}6.54%$ 증가된 결과를 나타냈으며, 단독운영은 실제 총발전량 보다 $12.68{\sim}38.94%$ 감소된 결과를 나타냈다.

• The Journal of Korean Physical Therapy
• /
• 제36권1호
• /
• pp.27-32
• /
• 2024

Purpose: This study was conducted to verify the effect of applying a pressure biofeedback unit on walking ability and knee joint function while performing knee joint extensor strengthening exercises using resistance exercise equipment in total knee replacement (TKR) patients. Methods: This study was conducted on twelve patients receiving rehabilitation treatment after being admitted to a rehabilitation hospital post-TKR. Of these, six were allocated to a feedback group with a pressure biofeedback unit, and the other 6 were allocated to a control group without a pressure biofeedback unit. The subjects performed an exercise program for 45 minutes per session, five times a week, for two weeks. Walking ability and knee joint function were evaluated and analyzed before and after exercise. Results: The feedback group showed significantly better improvements in walking speed, gait cycle, step length on the non-operation side, time on the foot on the operation side, K-WOMAC stiffness, and K-WOMAC function than the control group (p<0.05). Conclusion: When strengthening the knee joint extensor muscles using resistance exercise equipment in TKR patients, the provision of a pressure biofeedback unit was found to improve walking ability and knee joint function by inducing concentric-eccentric contraction of the knee joint extensor muscles. Therefore, the study shows that exercise based on the provision of a pressure biofeedback unit should be considered when strengthening knee joint extensor muscles to improve the walking ability and knee joint function of TKR patients in clinical practice.

• 한국수자원학회:학술대회논문집
• /
• 한국수자원학회 2007년도 학술발표회 논문집
• /
• pp.31-39
• /
• 2007

In this study we developed a turbidity management system to support the operation for effective turbid water management. The decision-making system includes various models for prediction of turbid water inflow, effective reservoir operation using the selective withdrawal facility, analysis of turbid water discharge in the downstream. The system is supported by the intensive monitoring devices installed in the upstream rivers, reservoirs, and downstream rivers. SWAT and HSPF models were constructed to predict turbid water flows in the Imha and Andong catchments. CE-QUAL-W2 models were constructed for turbid water behavior prediction, and various analyses were conducted to examine the effects of the selective withdrawal operation for efficient high turbid water discharge, turbid water distribution under differing amount and locations of turbid water discharge. A 1-dimensional dynamic water quality model was built using Ko-Riv1 for simulation of turbidity propagation in the downstream of the reservoirs, and 2-dimensional models were developed to investigate the mixing phenomena of two waters discharged from the Andong and Imha reservoirs with different temperature and turbidity conditions during joint dam operation for reducing the impacts of turbid water.

• 국제물리치료학회지
• /
• 제10권2호
• /
• pp.1791-1796
• /
• 2019

Background: Vibration exercise after ankle surgery improves proprioception and ankle muscle strength through vibration stimulation. Objective: To examine the effects of vibration exercise on the ankle stability. Design: Randomized controlled clinical trial (single blind) Methods: Twenty soccer players were randomly divided into experimental group and control group. The Vibration exercise program was conducted 12 weeks and 3 times a week. Ankle joint proprioceptive sensory test and Isokinetic muscle strength test were performed using Biodex system pro III to measure plantar flexion / dorsiflexion and eversion / inversion motion. Results: The result of isokinetic test of ankle joint is showed significant improvement in all measurement items, such as leg flexion, lateral flexion, external and internal muscle forces, compared to previous ones by performing vibration movements for 12 weeks. However, in the comparison group, plantar flexor ($30^{\circ}$), eversion muscle ($120^{\circ}$), inversion ($30^{\circ}$) of limb muscle strength were significantly improved compared with the previous phase; was no significant difference in dorsi-flexion. There was no significant difference between groups in all the items. Conclusions: In this study, we analyzed the effects of rehabilitation exercise on soccer players who had reconstructed with an ankle joint ligament injury through vibration exercise device. As a result, we could propose an effective exercise method to improve the ability, and confirmed the applicability as an appropriate exercise program to prevent ankle injuries and help quick return.

• 한국정밀공학회:학술대회논문집
• /
• 한국정밀공학회 2004년도 추계학술대회 논문집
• /
• pp.704-708
• /
• 2004

The RMD(Rehabilitation Medicine Device) with CJM(Compound Joint Motion) is the lower limb unit muscular strengthening promotion rehabilitation medicine device for patients of joint orthopedic operation or the deficient elder of ability to walk, the handicapped. Since the products for the rehabilitation medicine device have limited to the simplicity linear motion, those do not give efficient the lower unit muscular strengthening effects. This device which was under the development gives to exercise of hip joint and knee joint with user's selection at once, get out of the simplicity linear motion. Also it will be contributed to a field of rehabilitation medicine and a mobility aid technology of the deficient elders of ability to walk, the handicapped.

• 한국산학기술학회논문지
• /
• 제8권4호
• /
• pp.795-802
• /
• 2007

미 국방성은 미래 전장에서 네트워크화를 통한 전투 능력의 시너지 효과 증대를 도모하고 있다. 특히 Joint 2020에서는 전장에서 작전 수행시 합동군의 지식 우위와 결심 우위를 위한 정보 우위를 추구하고 있다. 본 연구에서는 미국을 중심으로 하는 네트워크 중심 작전에 대한 개념과 운용 사례를 살펴보고 작전운용 거리에 대한 정량적인 거리와 영향, 통신중계 성능을 분석하였다.

• 소음진동
• /
• 제9권5호
• /
• pp.1050-1057
• /
• 1999

The existence of clearance at the link joint of a machine is inevitable for assembly and mobility. During the cyclic operation of a machine, rapid changes of the direction and magnitude of connection forces cause momentary loss of contact between the pin and the bushing at the link joint. Contact loss at the clearance joint gives rise to undesirable impact. The impulsive force affects on the performance of the machine, and leads to excessive vibration, noise and faster wear in the connecitons. In this paper, experiment and theoretical analysis were carried out for the variation of crank speed and clearance size. The link mechanism employed in this investigation was newly designed to check the effects of parameter changes on the occurrence of contact loss and on the magnitude of the impact force. The contact loss and impact position were calculated with various driving conditions.

• 한국소음진동공학회:학술대회논문집
• /
• 한국소음진동공학회 2002년도 추계학술대회논문집
• /
• pp.328-333
• /
• 2002

When vehicle travelling along the track which has irregularity such as vertical profile, dynamic forces arise at the Wheel/Rail contact patch by wheel/rail interaction. In particular short wavelength irregularities on dipped joint and small stiffness of connecting rail bring about intense wheel/rail dynamic effects at higher speed. In the paper, a new model for dipped joint rail is developed to study dynamic behavior of track. A cusp behavior on dipped joint was defined by its amplitude and decay factor, which was presented by FRA track classes. The result of case study are presented, which show wheel rail contact force in each track classes, train operation speed and bending flexible rigidity ratio of fishplates which are connecting the rail.

• The Journal of Korean Physical Therapy
• /
• 제28권1호
• /
• pp.27-32
• /
• 2016

Purpose: The purpose of this study is to examine the effects of sensorimotor training on knee joint stability after anterior cruciate ligament reconstruction. Methods: The subjects were sixteen 16 adults who received anterior cruciate reconstruction by arthroscopy, and underwent sensorimotor training for which was to have them maintenanceain of a standing position with a step Balance ball on the affected side over 30 degrees knee flexion with 100% weight bearing for 15-20 seconds. Before the genuine experiment commenced, the Lysholm scale was had been used to assess functional disorders on the affected knee joint. KT-2000 Arthrometer measurement equipment was used to measure anterior displacement of tibia against to femur before and after the sensorimotor training. Results: There was significant relaxation on the affected side in tibia anterior displacement of the affected and sound sides on in supine position before the sensorimotor training. There was little significant difference in tibia anterior displacement of the affected knee joints on in the supine position before and after the sensorimotor training. The results also showed that there was a reduction in the difference of tibia anterior displacement of the affected knee joints on in the standing position. These results suggest that the effects of sensorimotor training on knee joint stability after anterior cruciate ligament reconstruction is to induce the change of tibia anterior displacement against femur and the variation of muscles activation. Conclusion: The sensorimotor training may contribute to the improvement of joint functional stability in people who are in post-operation state and with orthopedic musculoskelectal injuries.

• 대한용접접합학회:학술대회논문집
• /
• 대한용접접합학회 2003년도 춘계학술발표대회 개요집
• /
• pp.216-218
• /
• 2003

A fracture mechanics analysis methodology for stress corrosion cracks (SCCs) existing in the Alloy 600 nozzle weld joint for control rod drive mechanisms (CRDMs) of pressurized water reactor is studied. Effects of weld residual stresses on the sub-critical crack behavior during the reactor operation are investigated by a fracture mechanics analysis, which is combined with the finite element alternating method. It is found that effects f the residual stresses on the stress intensity factor (SIF) and crack growth rate (CGR) are dominant and values of SIF and CGR of cracks in the region of weld joint are increased by a factor of three or more on an average.