• Transactions of the Korean Society of Mechanical Engineers A
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• v.41 no.7
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• pp.591-597
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• 2017

This study is to develop a vehicle Integrated Dynamics Control System(IDCB) that can stabilize the lateral dynamics and maintain steerability. To accomplish this task, an eight degree of freedom vehicle model and a nonlinear observer are designed. The IDCB independently controls the brake systems of four wheels with a fuzzy logic control and a sliding model control. The result shows that the nonlinear observer produced satisfactory results. IDCB tracked the reference yaw rate and reduced the body slip angle under all tested conditions. It indicates that the IDCB enhanced lateral stability and preserved steerability.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.37 no.11
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• pp.1371-1377
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• 2013

In this analysis, a method is presented to calculate the critical speed of a railway vehicle by using a multibody dynamic model. The contact conditions and contact forces between the wheel and the rail are formularized for the wheelset model. This is combined with the bogie model to obtain a multibody dynamic model of a railway vehicle with constraint conditions. First-order linear dynamic equations with independent coordinates are derived from the constraint equations and dynamic equations of railway vehicles using the QR decomposition method. Critical speeds are calculated for the wheelset and bogie dynamic models through an eigenvalue analysis. The influences of the design parameters on the critical speed are presented.

• Archives of design research
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• v.11
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• pp.1-9
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• 1995

Scandinavian design has special meaning in design history. Especially the Swedish designers have developed elegant and humane design style by combining the functionalism originated in Germany in the beginning of 20th century with their own crafts tradition. Now 'Swedish Modern' or 'Swedish Grace' is regarded as the most preferrable style for modern industrial society. American design as well as European design has been much changed under the influence of this democratic, simple and beautiful style. To find out the essential qualities of Swedish design style, I want to investigate the history of modern Swedish design and the design mechanism in Swedish corporates. Also I want to introduce the design education system in Sweden, which has contributed to developing contemporary Swedish design philosophy.

• Journal of the Society of Naval Architects of Korea
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• v.29 no.1
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• pp.55-60
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• 1992

A study has been made on the hydrodynamic forces on and the motion response of a sliding block in a bay within the framework of linear potential theory. To simplify the problem, following assumptions are made : The configuration of the bay is a long channel with narrow width, constant depth and straight coastline. Incident waves are long compared to the depth. We applied matched asymptotic expansion techniques. The flued domain is subdivided into three regions ; ocean, bay entrance, bay regions. Boundary-vague problems are solved first in each region. Then unknown coefficients are determined by matching individual solutions at the intermediate region between two neighboring legions. It is found that the motion of the block is greatly amplified at the resonant frequencies, in particular at the quarter wavelength mode. We examined the mechanism of negative added mass, which results from the localized hydrodynamic resonance.

• Journal of the Korea Convergence Society
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• v.12 no.4
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• pp.179-190
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• 2021

This study tried to provide the way of development in sport-climbing base on the history and present of Korean sport climbing. In terms of the policy, single sport climbing association needs to be formed and separated from Korean Alpine Federation. School teams and athletes are required to expand, college teams in particular. These athletes could be sport instructors and professional athletes vitalizing competition and sport climbing after graduation. Public sport climbing facilities need to be counted accurately. Ministry of Culture, Sports and Tourism needs to administrate the public sport blimbing facilities by counting and checking the facilities with the responsibility.

• 한국노년학
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• v.25 no.2
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• pp.143-154
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• 2005

This study was conducted to examine the environmental status, FIM(Function Independence Measure), Illness intrusiveness of home stayed stroke patients. Data were collected on 145 patients living in K city and the neighborhood located in southern part of Korea. The data were analyzed by means of SPSS program. Results : In assessment of environmental safety, 46.2%(67) felt unsafe around their residential area. The most dangerous facilities in their residence was stairs(58.2%), gas/electric facilities(14.9%). For sanitary problems, 28.2%(41) felt they have problems at their home. The most important problems were outdoor polluted toilet(22.0%) and scattered and dirty residential circumstances(22.0%). The average FIM score was 74.52(4.14) of total score 126(7). In motor area FIM was lowest at stair walking(3.01) and bathing(3.16). In cognitive area FIM was lowest at social activities(3.36). The mean score of Illness intrusiveness was 58.86(4.52) of total score 91(7). The major area largely impacted by stroke were health(5.61), working(5.68), active leisure activities(5.56). There was significant reverse correlation between FIM and illness intrusiveness(r=-0.66, p=0.00). Conclusion : It was needed environmental improvement and rehabilitation program for stroke patients, and repeated follow up study.

• Journal of the Korean Applied Science and Technology
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• v.34 no.4
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• pp.756-768
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• 2017

The subjects for the study were twenty four obese women(50's) composed of the exercise group(n=12) and to a "no exercise" control group(n=12). The variables of health-related fitness, blood pressure, and blood vessel elasticity where measured in all the subjects before the start of the training program and after at the end of the 8 weeks circuit training. The test data were analyzed by t-test, paired t-test, and alpha level of p<.05 was set for all tests of significance. Health-related fitness was exercise group, the BMI had significantly decreased, and the 20m shuttle run, sit-ups and sit-and-reach had significantly increased. Blood pressure was exercise group, the systolic blood pressure, and diastolic blood pressure had significantly decreased. Also, after the circuit training program, the exercise group had significantly higher diastolic blood pressure than did the control group. blood vessel elasticity was exercise group, the blood vessel elasticity had significantly decreased. And exercise group had significantly higher diastolic blood vessel elasticity than did the control group. In conclusion, BMI, systolic blood pressure, and diastolic blood pressure had significantly decreased, but 20 m shuttle run, sit-ups and sit-and-reach had significantly increased in the combined exercise group after the 8 weeks circuit training. Therefore, regular and continuous circuit training were effective in improving the body composition, blood pressure, blood vessel elasticity and health-related fitness.

• Sleep Medicine and Psychophysiology
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• v.7 no.1
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• pp.34-42
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• 2000

Objectives: Periodic limb movements in sleep(PLMS) is a moderately prevalent disorder, of which pathophysiology remains largely unknown. PLMS has been reported to be common in patients with obstructive sleep apnea syndrome(OSAS), but reports on their relationship have been inconsistent in previous studies. Inconsistency of results may be attributable to insufficient number of the study subjects. We attempted to explore the influence of OSAS on PLMS in a large number of subjects. Methods: Three hundred and twenty subjects(M : F=192:128) with PLMS, as identified by the nocturnal polysomnography, were studied. Sample mean age was 53.1(SD=15.1) years and their mean periodic limb movement index(PLMI) is 25.2/hr (SD=24.8). PLMS subjects were divided into two groups, based on the presence or absence of OSAS. Periodic limb movement indices and sleep parameters between two groups were analyzed to evaluate the effects of OSAS on PLMS. Results: Each of PLMI and PLMI with arousal(PLMAI) correlated positively with age. PLMI of men was larger than that of women (p<0.01). The presence of comorbid OSAS independently had influence on PLMI(t=-2.20, p<0.05), but not PLMAI. There were no significant differences between the two groups in their PLMI, PLMAI and sleep parameters. However, the two groups differed in PLMI-correlated sleep parameters. In PLMS subjects with comorbid OSAS, PLMI was negatively correlated with each of slow wave sleep time and REM sleep time. In subjects without comorbid OSAS, PLMI was negatively correlated with sleep efficiency. Conclusion: PLMS patients with OSAS turned out to have increased PLMI than those without OSAS We suggest that OSAS patients may have subtle autonomic arousals and these arousals could, in part, express themselves as PLM.

• Journal of the Korean Applied Science and Technology
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• v.36 no.4
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• pp.1312-1326
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• 2019

The purpose of this study is to examine whether the 12-week Nordic walking can improve the physical function and arthritis pain of elderly women with osteoarthritis This study were divided into randomly assigned Nordic Walking Exercise Group (n=9) and Control Group (n=7) for 16 Elderly women diagnosed with Osteoarthritis (age: 73±3.79 year, height: 154.3±4.09 cm). The exercise group used Nordic sticks to carry out 30 minutes of Nordic walking exercise three times a week for 12 weeks, and the kinetic intensity was set at 40-60% of HRR. The control group maintained daily life for the same period. Body composition (weight, percentage body fat, skeletal muscle mass), muscular strength, Flexibility (muscular strength of upper and lower limbs, flexibility of upper and lower limbs), balance ability (static balance, dynamic balance) and pain level were measured as subordinate variables. These indicators were measured twice before and after the exercise program. The study shows that percentage body fat and skeletal muscle mass in the body composition function over 12 weeks of Nordic walking exercise have significant effects after the exercise than before (p=004)(p=.003), and it also shows significant interaction effects between the groups and timings(p=.018)(p=.005). In muscular strength, Flexibility factors, there were significant effects between the groups and timings in the upper limb muscular strength and the lower limb flexibility (p=.009)(p=.036), and a significant difference between the exercise group and the control group(p=.006) in the lower limb muscular strength. In addition, in the upper limb flexibility, there was a more significant difference after the exercise than before(p=.020). There were improvement effects after the exercise than before in the balance ability and the static balance(p=.016), but no difference in the dynamic balance(p>.05). In pain, there was a significant improvement after the exercise than before(p=.022), and a significant difference between the exercise group and the control group(p=.013). In conclusion, the 12-week Nordic walking exercise has positive effects on the body composition functions of the elderly women with Osteoarthritis, and has a positive effect on the improvement of upper limb muscular strength and lower limb flexibility in the health fitness factors. These effects are believed to have contributed effectively to the improvement of the level of pain by contributing to the improvement of physical and motor functions of the elderly women with Osteoarthritis. Therefore, it is considered that Nordic walking exercise, which enhances stability and balance of the patients with Osteoarthritis by using poles, is an effective exercise method for the improvement of the body and motor functions by lowering the pain of the joints and reducing the muscular strength and percentage body fat.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.7
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• pp.4395-4403
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• 2014

The purpose of study was to compare the effectiveness of sling exercise on the muscle strength and range of motion in female patients who received a total knee replacement. The participants were allocated randomly into 2 groups: sling exercise group (n=15) and control group (n=15). The subjects were evaluated using the Biodex system for the muscle strength test and a goniometer for the range of motion test. The data was analyzed using a paired t-test and independent t-test to determine the statistical significance. As a result, the sling exercise group before and after intervention showed a statistical significance difference in the flexion angle, quadriceps femoris, and hamstring muscle strength. The control group before and after the intervention revealed a statistically significant increase in the flexion & extension angle, quadriceps femoris, and hamstring muscle strength. Muscle strength test and flexion range of motion test in the sling exercise group showed statistical significance differences compared to the control group (p<.05). Therefore, the sling exercise group has a positive influence on the muscle strength and ROM in patients with a total knee replacement.