• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2010.06a
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• pp.119-119
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• 2010

Among the various factors influencing the service life of the electric equipment, the performance of dielectric insulation materials has an important role to determine their whole service life. In order to determine the degradation of insulating materials immersed in extremely low temperature media such as liquid nitrogen, the abrupt temperature change from cryogenic to normal room temperature should be considered. But the assessments of low-temperature aging test method for the dielectric materials immersed in liquid nitrogen considering these conditions were not fully reported. Therefore, for the fundamental step to establish the suitable degradation test methods for cryogenic dielectric materials, we focused on the evaluation of ageing test methods for dielectric materials exposed to low temperature environments considering thermal shock by cool-down and warm up test.

• Transactions of the Korean hydrogen and new energy society
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• v.7 no.2
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• pp.121-128
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• 1996

A direct cooling equipment for hydrogen liquefaction has been developed and tested. A direct cooling equipment consists of a liquefaction vessel, a radiation shield, a cryostat and a GM refrigerator. The cool-down and warm-up characteristics of the liquefaction apparatus have been investigated in detail. It is found that the hydrogen starts to be liquefied in the liquefaction vessel after 45 minutes of cool-down. The cool-down and warm-up tests of helium gas are also performed. The cool-down and warm-up characteristics of helium gas are found to be very different from those of hydrogen gas, since helium is not liquefied under the present operating conditions. When the liquefaction vessel is evacuated, natural convection phenomena of charged gas in liquefaction vessel can be removed. It is seen that the cool-down time of liquefaction vessel is substantially increased in vacuum environment.

• Physical Therapy Rehabilitation Science
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• v.2 no.1
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• pp.57-61
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• 2013

Objective: To determine the correlation among three functional tests: single leg vertical jump (SLVJ), single leg hop for distance (SLHD), and single leg squat (SLSQ). Design: Cross sectional study. Methods: Twenty healthy men (n=10) and women (n=10) with no history of lower extremity dysfucntion participated in this study and performed in university research laboratory. The procedures consisted of a general warm-up, a task-specific warm-up, actual testing, and a cool down. All participants performed the three tests in random order. Each test was performed three times for the dominant and non-dominant lower extremity (LE). SLVJ, SLHD, SLSQ were measured using a standard tape measure. Results: Statistically significant difference was presented between dominant LE and non-dominant LE in each function test (p<0.05). The strongest correlation was between SLVJ and SLSQ, 0.939 and 0.883 for dominant and non-dominant LE, respectively (p<0.05). The weakest correlation was between SLVJ and SLHD, 0.713 for dominant (p<0.05) and between SLSQ and SLHD, 0.739 for non-dominant (p<0.05). Conclusions: There is a strong correlation between SLVJ and SLSQ, suggesting that each test measures similar constructs of function and can be substitutive, while weak correlation between SLSQ and SLHD suggest these two tests do not measure the same functional components and could be paired as outcome measures for the clinical assessment of LE function. It will provide physical therapist with scientific evidence for effective test combination of LE function assessment in clinical practice.

• Journal of International Academy of Physical Therapy Research
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• v.3 no.2
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• pp.440-445
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• 2012

The purpose of this study was to assess the effects of lower extremity resistance training using elastic bands on balance in elderly people. Eight elderly persons each were randomly assigned to a test group(resistance exercise group, REG) or a control group(CG). FRT and TUG test were used to compare balance before and after exercise. Exercise programs were implemented three times a week for 40 minutes for nine weeks. They did warm-up exercise for 5 minutes and then lower extremity resistance exercise using elastic bands for 30 minutes. And then they did cool-down exercise for 5 minutes. TUG and FRT significantly decreased but in the control group it did not significantly decrease. In comparison between the groups, TUG and FRT significantly reduced in the resistance exercise group compared to the control group. Lower extremity resistance training using elastic bands performed by elderly persons are considered to be effective in improving balance.

• Physical Therapy Korea
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• v.1 no.1
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• pp.83-87
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• 1994

The purpose of this paper is to provide an overview of the clinical physical therapy program used at the University of Yonsei Rehabilitation Hospital, for the practicing university trained physical therapists who may be unfamiliar with patients who have suffered a myocardial infarction. The four primary phases of the cardiac physical therapy graded exercise program are: 1) coronary care unit program (phase I), 2) general ward program (phase II), 3) convalescence program (phase III), 4) maintenance program (phase IV). The exercise prescription defines the exercise intensity, duration, frequency, and mode of exercise a after pre- discharge low level graded exercise test(LL-GXT) or symptom limited maximum graded exercise test. A typical exercise routine consists of preparation warm-up exercise, therapeutic exercise, cool-down exercise. Physical therapy is involved in the acute care and rehabilitation of the patient after a myocardial infarction. Therefore, the physical therapist must throughly comprehened the cardiac anatomy, cycle, performance, conduction system, pathogenesis, risk factors, and exercise benefits.

• Proceedings of the KSME Conference
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• 2007.05b
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• pp.2206-2210
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• 2007

As a power transmission line supplying power to a densely populated city, the high temperature superconducting (HTS) cable is expected to one of the most effective cables with a compact size because of its high current density. The verification of HTS power cable system have been progressed by KEPRI. A cooling system for a 3-phase 100m HTS power cable with 22.9kV/1.25kA was installed and tested at KEPCO's Gochang power testing center in Korea. The system consists of a liquid nitrogen decompression cooling system with a cooling capacity of 3kW and a closed circulation system of subcooled liquid nitrogen. Several performance tests of the cable system with respect to the cooling such as cooling capacity, heat load and temperature stability, were performed at several temperatures. Thermal cycle test, cool-down to liquid nitrogen temperature and warm-up to room temperature, was also performed to investigate thermal cycle influences. The outline of the installed cooling system and performance test results are presented in this paper.

• The Journal of Korean Physical Therapy
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• v.31 no.5
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• pp.311-316
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• 2019

Purpose: Generally, patients with stroke present with decreased balance and increased spasticity following weakness of the paralyzed muscles. Muscle weakness caused by stroke has two causes. This is caused by a decrease in motor output and an adaptive muscle change, resulting in muscle weakness and muscle paralysis. The purpose of this study was to investigate the effect of strengthening exercise on balance and spasticity in chronic stroke patients and to suggest the basis of clinical treatment. Methods: Twenty subjects were divided into two groups: a lower-extremity strengthening group (experimental group) and a general physical therapy group (control group). The sliding stander equipment was used for the experimental group and a regimen of warm-up exercise, the main exercise routine, and cool-down exercise were used for the muscle strengthening exercise program. Balance and spasticity were measured before and after the training period. Balance ability was measured by the Berg balance scale, the Timed up and Go test and the weight distribution of the paralyzed muscles by the Spacebalance 3D. Spasticity was measured by the Biodex system. Results: After the training periods, the experimental group showed a significant improvement in BBS, weight distribution of the paralyzed muscles, and decreased spasticity when compared to the control group (p<0.05). Conclusion: This study supported the hypothesis that lower-extremity strengthening exercise improves the balance and decreases the spasticity of stroke patients. If it is combined with conventional neurologic physiotherapy, it would be effective rehabilitation for stroke patients.

• The Journal of Korean Physical Therapy
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• v.17 no.2
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• pp.11-22
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• 2005

Purpose: The purpose of this study was to investigate the effects of aquatic health exercise program for the old. Methods: 20 healthy female with an average age of 71years($71{\pm}4.2$), were participated in this study. The aquatic health exercise program that include warm-up, stretching, strengthening exercise, WATSU and cool-down was performed in the pool two times a week for eight weeks(40min per one session). Body composition, strength of the both knee flexors and extensors, balance ability(sway area and path), whole body reaction time and flexibility(forward reaching test in long sitting) were measured before and after exercise. The data was analyzed with paired t-test to determine significant differences of all suggested factors between pre and post-exercise by make use of the SPSS(ver 10.0) package program. Results: The strength of the both knee flexors and extensors were increased significantly(right knee; p<0.01, left knee; p<0.05). Anteroposterior sway area (p<0.01), and sway path (p<0.001) of both leg were reduced significantly with eyes closed and opened. Whole body reaction time by optical stimulation was increased significantly (p<0.01) but whole body reaction time by auditory stimulation was no significant difference. The flexibility was increased significantly (p<0.01). Conclusion: Aquatic health exercise program can improve muscle strength, balance, whole body reaction, and flexibility.

• PNF and Movement
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• v.16 no.1
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• pp.7-17
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• 2018

Purpose: The aim of this study was to investigate the effects of coordinative locomotor training in a chronic stroke patient. Methods: A left hemiplegic patient diagnosed with a right middle cerebral artery stroke participated in this research. The patient's functional conditions were assessed, and a coordinative locomotor training program was initiated to resolve the problems identified. A set of movements deemed difficult based on the brief International Classification of Functioning, Disability and Health core set for stroke and d4501 (long-distance walking) were agreed as improvement targets. The program comprised warm up, main, cool-down, and home exercises. Repeated measurements were obtained, as follows: five times at baseline (A), 10 times during the intervention (B), and five times after the intervention (A). The study period was 7 weeks, and the intervention period was 1 h per day, twice a week for 5 weeks. Various tools, including the community walking test (CWT), 10-m walking test (10 MWT), 6-min walking test (6 MWT), and timed up and go (TUG) test, were conducted to assess the patient's walking ability. Changes in functional domains before and after the ICF Qualifier were compared. The mean values of the descriptive statistics were calculated, and a visual analysis using graphs was used to compare the rates of change. Results: The results showed that the CWT, 10 MWT, 6 MWT, and TUG test scores during the intervention period improved and that this improvement remained, even during the baseline period. In addition, the ICF Qualifier before and after the comparison decreased from moderate to mild. Conclusion: Based on the results, we propose that coordinative locomotor training can have positive effects on community ambulation of chronic stroke patients.

• The Journal of Korean Physical Therapy
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• v.21 no.4
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• pp.23-30
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• 2009

Purpose: This study investigated the efficacy of task-related circuit training aimed at improving balance in individuals discharged from rehabilitation facilities following a stroke. Methods: We recruited 12 stroke patients (34-66 years of age) to participate in a task-related circuit training program. Baseline assessment included a history of stroke and an assessment using the Mini-Mental State Examination Korea (MMSE-K). After a baseline assessment, follow-up assessments were administered pre- and post-training. These included Berg Balance Scale (BBS), Functional Reach Test (FRT), and the Time Up & Go Test (TUG). Physiotherapists trained study subjects under the one-to-one supervision of students from the department of physical therapy. Circuit class study participants attended 90-minute treatment sessions, one day a week for 12 weeks (from September to December 2008). The program consisted of a light warm-up period (10 min), physical exercises for improving balance (20 min), tasks focused on improving balance (50 min) and a cool-down period (10 min). Results: Scores for the BBS assessment increased significantly (from 43.2 to 49.7) after the training (p<0.05). Reach distance on the FRT increased substantially (from 27.7 cm to 47.0 cm), although the improvement was not significant (p>0.05). The average time on the TUG test decreased significantly (from 23.7 sec to 19.5 sec) after the training (p<0.05). Conclusion: The task-related circuit training program improved the balance and mobility of subjects, indicating that such a group program is useful for stroke patients who are discharged from the hospital. More such task-related programs set in a community environment should be developed.