• Journal of Power Electronics
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• v.15 no.1
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• pp.146-159
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• 2015

Since the power capacity needed for the propulsion of large ships is very large, a multiphase AC induction propulsion mode is generally adopted to meet the higher requirements of reliability, redundancy and maintainability. This paper gives a detailed description of the development of a 20MW fifteen-phase PWM driver for advanced fifteen-phase propulsion induction motors with a special third-harmonic injection in terms of the main circuit hardware, control system design, experiments, etc. The adoption of the modular design method for the main circuit hardware design can make the enclosed mechanical structure simple and maintainable. It can also avoid the larger switch stresses caused by the multiple turn on of the IGBTs in conventional large-capacity converter systems. The use of the distributed controller design method based on a high-speed fiber-optic ring net for the control system can overcome such disadvantages as the poor reliability and long maintenance times arising from the conventional centralized controller which is designed according to point-to-point communication. Finally, the performance of the 20MW PWM driver is verified by experimentation on a new fifteen-phase induction propulsion motor.

• Journal of Chest Surgery
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• v.24 no.2
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• pp.197-201
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• 1991

Twenty-three patients with traumatic diaphragmatic injuries treated at the Department of Thoracic and Cardiovascular Surgery, Keimyung University Dongsan Medical Center from Aug. 1978 to Nov. 1990 were reviewed. There were 19 male and 4 female patients. The age distribution was ranged from 1.5 to 72 years, with a mean age of 34.3 years. Sixteen patients had blunt trauma[traffic accident 14, fall down 2], and 7 had penetrating injuries[stab wound 6, broken glass 1]. Sixteen [70 percent]of the injuries occurred on the left side and 7[30 percent] on the right side. Fifteen patients were operated on during the acute phase, 5 patients during the latent phase, 2 patients during the obstructive phase. The surgical approach in 20 patients was through a thoracotomy; in 2 patients, a thoracoabdominal incision was necessary, and in 1 patient, a laparotomy was performed. Herniated organs in thorax included stomach[10], colon[5], small bowel[5], spleen[4], liver[2]. Postoperative complications included wound infection, empyema, pneumonia, hepatitis and respiratory failure. There were 3 postoperative deaths, 2 with cerebral dysfunction and 1 with sepsis.

• The Journal of Korean Physical Therapy
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• v.23 no.3
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• pp.1-5
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• 2011

Purpose: This study examined the relationship between the center of pressure (COP) displacement time during the stance phase and dynamic balance ability when older adults cross a 10 cm obstacle. Methods: Fifteen older adults were enrolled in this study (all ${\geq}65$ years of age). The F-scan was used to measure the COP displacement time when subjects cross a 10 cm obstacle, and the Dynamic gait index. Berg's balance scale and the Four square step test were used to measure dynamic balance ability. Results: The Dynamic gait index, Berg's balance scale and the Four square step test were correlated with each other. Dynamic balance ability was correlated with COP displacement time during the stance phase at an obstacle crossing in older adults. Conclusion: People with higher dynamic balance ability show a smaller COP displacement time during the stance phase at an obstacle crossing. Therefore, dynamic balance ability can be predicted by measuring the center of pressure displacement time.

• The Journal of Korean Physical Therapy
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• v.23 no.2
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• pp.1-5
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• 2011

Purpose: This study examined the difference in the center of pressure (COP) displacement time in older adults according to the obstacle height during stance at each sub.phase when crossing obstacles. Methods: Fifteen older adults were enrolled in this study (${\geq}65$ years of age). The F-scan was used to measure the COP displacement time when crossing a 0, 10 and 40cm obstacle, and the stance phase was divided into 4 sub-phases according to the foot contact pattern. Results: During the stance phase, the COP displacement time increased with increasing obstacle height. During the mid-stance, terminal stance and pre-swing except for the loading response, there were significant differences in the COP displacement time according to the obstacle height. Conclusion: This study suggests that older adults show differences in the COP displacement time according to the stance sub-phase while crossing obstacles, and they use different mechanisms according the sub-phases to maintain balance during obstacle crossing.

• Women's Health Nursing
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• v.10 no.2
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• pp.162-170
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• 2004

Purpose: The purpose of this study was to differentiate between women with three perimenstrual symptom severity patterns : premenstrual syndrome(PMS), premenstrual magnification(PMM), and low symptom(LS), and to explore the related dietary factors to premenstrual symptoms. Method: Women were asked to keep a diary record of perimenstrual symptoms and food intake for 50 days. Result: Symptom patterns were defined for 26 among 38 women ; Eight(21.1%) demonstrated a PMS pattern, three(7.9%) demonstrated a PMM pattern, and fifteen(39.5%) exhibited a LS pattern. There were significant differences in symptom scores during the premenstrual phase($x^2=19.30$, p=.000), menstrual phase($x^2=13.32$, p=.001), and post menstrual phase($x^2=9.93$, p=.007) for three groups. Protein, vit E, vit C, niacin, folic acid, and phosphorus in the premenstrual phase, and energy, and vit B6 in the menstrual period were significantly different between the three groups. Among dietary compositions, amino acids, lipids, fatty acids, saturated fatty acids, natrium, vit B6, niacin, and vit E were negatively related to PMS symptoms. Conclusion: Pattern of perimenstrual symptoms should be differentiated for individualized PMS management. As a more efficient diet assessment for PMS women, randomized nutritional analysis during the 3 phases of the menstrual cycle should be done and a replication study is necessary with a larger sample.

• Journal of the Korean Academy of Clinical Electrophysiology
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• v.3 no.1
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• pp.1-12
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• 2005

This study aimed at examining the maximal isometric contraction caused by voluntary exercise and at comparing its aspects of decrease and restoration in their different repeated application, as to the quadriceps muscles of thigh in the subjects composed of patients with spastic hemiplegia and normal adults. Using isokinetic exercise analyser(Biodex Medical Systems Inc., Biodex System 3PRO, U.S.A.), experiment was conducted as to the normal group composed of fifteen adults and the patient group composed of fifteen patients with spastic hemiplegia. As to each group, MVIC(maximal voluntary isometric contraction) of the quadriceps muscle of thigh caused by voluntary exercise and the aspects of decrease and restoration of the isometric contraction were examined with the method to induce isometric exercise, and their SDI(strength decrement index) and SRI(strength recovery index) were also calculated. The results can be summarized as follows: 1. As for decrease of maximal isometric contraction, both groups showed slow decrease in voluntary exercise, but the normal group showed rapid decrease later phase. 2. As for SDI, no significant differences could be observed in comparison between groups. 3. As for restoration of maximal isometric contraction, both groups showed slow restoration in voluntary exercise, but the normal group showed rapid restoration early phase. 4. As for SRI, comparison between groups showed significant differences in voluntary exercise. These results lead us to the conclusions that spastic muscle is characterized by slow decrease and restoration of MVIC in comparison with normal muscle in voluntary exercise.

• Asian-Australasian Journal of Animal Sciences
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• v.12 no.8
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• pp.1285-1291
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• 1999

A feeding trial was carried out over 238 days to determine the effect of compensatory growth in crossbred calves having 166 kg body weight. Fifteen crossbred calves were divided into two groups of five calves (G1 group) and ten calves (G2 group) as per randomized block design. Growth study was conducted on the feeding of wheat straw based diet containing 60 and 30 percent concentrate supplying equal amount of protein in group G1 and G2 respectively for 119 days (phase - I). At the end of phase-I, calves of G2 group were subdivided in to two groups (G3 and G4). One sub group (G4) received 60% concentrate in their diet (during 120 to 238 days of experiment) while other subgroup G3 received 30% concentrate in their diet (phase-II). The calves of G1 group continued to receive the same diet as during phase-I experiment. Mean DM intake was significantly higher in calves fed high level of concentrate (in G1 and G4 groups), which resulted in significantly higher digestibility of all nutrients except NDF. Nitrogen balance was positive in all the groups and showed significant differences in phase-II (higher nitrogen retention in G4 group than G1 group). ME intake was significantly affected by the level of dietary concentrate, being higher in high concentrate fed group (G1 and G4 than G2 and G3 group). Higher daily body weight gain in the calves of G4 group during phase-II than in G1 and G3 groups was due to compensatory growth on shifting animals from low concentrate to high concentrate based ration. Average daily body weight gain was higher in phase-I than in the phase-II. Protein and energy intake per unit body weight gain were significantly lower in calves fed high concentrate diet.

• The Korean Journal of Nuclear Medicine
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• v.17 no.1
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• pp.63-69
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• 1983

Fifteen cases of Korean hemorrhagic fever who were admitted Chungnam National University Hospital from October 1981 to December 1981 were analysed on the evaluation of metabolic.changes of the thyroid hormones, and thyroid function status in each clinical phase. 1. Serum $T_3,\;T_4$ concentratron, $FT_4I\;and\;T_4/TBG$ ratio were significantly lower (p<0.001, p<0.005, p<0.005, p<0.001, respectively) than control group in oliguric and early diuretic phase of Korean hemorrhagic fever. With the recovery of illness, abnormal thyroid hormones and thyroid function indices tend to become normal range. But Serum $FT_4$, TSH and TBG concentration were within normal range in all phase of KHF. Thus in Korean hemorrhagic fever, euthyroidism is probably maintained by normal or elevated serum $FT_4$ 2. $T_4/T_3\;and\;rT_3/T_3$ rato (p<0.005, p<0.005) were increased in oliguric and early diuretic phase of KHF. These results might be explained by decreased peripheral conversion of $T_4\;to\;T_3$ in oliguric and early diuretic phase.

• Journal of The Korean Society of Integrative Medicine
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• v.2 no.3
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• pp.57-63
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• 2014

Purpose : The purpose of this study was to identify the muscle activity of leg during stair down in the subjects with flatfoot and normal foot. Methods : The fourteen subjects with the flatfoot group and the fifteen subjects with the normal foot group volunteered for this study. All subjects descended the stairs that the height was 20cm and consisted 25 stairs. The target muscles for recording muscle activity were posterior fiber of gluteus medius, vastus medialis and vastus lateralis oblique, semitendinosus and biceps femoris, tibialis anterior, and medial and lateral fiber of gastrocnemius muscles. The muscle activity was recorded using the wireless EMG system. Results : The flatfoot group had significantly lower the muscle activity of posterior fiber of gluteus medius than the normal foot group in stance phase during stair down(p<.05). The flatfoot group had significantly higher the muscle activity of biceps femoris and tibialis anterior than the normal foot group in swing phase during stair down(p<.05). Conclusions : This study proposed that the subject with flatfoot should train the strengthening exercise for posterior fiber of gluteus medius.

• Journal of the Korean Society of Physical Medicine
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• v.3 no.3
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• pp.177-183
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• 2008

Purpose : The purpose of this study was to investigate characteristics of the muscle activities during level walking and stairs ascending in young adults. Methods : Fifteen young adult were recruited this study. Muscle activity (BIOPAC System Inc., Santa Barbara, U.SA). Statistical analysis was difference between level and stair walking. Results : In stance phase, muscle activity of low extremity generally more increased during ramp ascent both young adults. In swing phase, muscle activity of low extremity generally more increased during stairs ascent in young adults. Conclusion : These results indicate that stair and ramp ascent is more difficult task than level walking in young adults. Muscle activity was more changed at ramp ascent. In the future, we suggest that studies of stair and ramp gait pattern regarding ambulatory patient with disabilities be further studied and an appropriate stairs and ramp inclination will be indicated.