• The Journal of Korean Physical Therapy
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• 제28권5호
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• pp.264-268
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• 2016

Purpose: This study was conducted to investigate the effects on muscle thickness and balance ability after performing plank exercise on various surface types. Methods: In this study, there were thirty healthy participants. Participants were randomly distributed into three groups, a control group (n=10), sling group (n=10), and ball group (n=10). All participants performed plank exercises three times a week for four weeks. Plank exercises consisted of five sets of 30 seconds each with a one minute break between each set. Muscle thickness of the transverse abdominis (TrA), internal oblique (IO), and external oblique (EO) was measured using an ultrasound diagnostic apparatus and balance was measured using I-balance. Results: Evaluation of muscle thickness revealed that the IO and EO muscle of the ball group changed significantly relative to the control group (p<0.05). However, there were no significant changes in balance. Conclusion: The results revealed that performing plank exercise on a ball is more effective among various types of surfaces.

• 대한물리의학회지
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• 제15권1호
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• pp.11-18
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• 2020

PURPOSE: This study was to investigate examined the differences in the autonomic nervous functions of elite female judo athletes according to their performance by measuring the heart rate variability (HRV). METHODS: Sixteen elite female judo players participated in this study. The participants were divided into a high performance and low performance group according to the results of their competitions. The HRV (mean heart rate, SDNN, RMSSD, TP, LF, HF, LF/HF ratio) was measured in the resting status. A t-test was used to compare the two groups, and bivariate logistic regression analysis was performed to determine the HRV elements that affect performance. The data were analyzed using IBM SPSS Statistics ver. 24.0 (IBM Co., Armonk, NY, USA). RESULTS: The mean heart rate was higher in the high performance group (72.88) than in the low performance group (64.75) (p=.049). The LF/HF ratio was higher in the high performance group (3.43) than in the low performance group (0.83), and the results were significant (p=.038). No HRV elements having a significant effect on the performance were observed. CONCLUSION: This study showed that the activity of the sympathetic nervous system was dominant in the high performance group in the resting status than in the low performance. The high performance group is believed to be in the overtraining status who experience more stress.

• 암석학회지
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• 제11권3_4호
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• pp.250-258
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• 2002

석영의 파동소광은 암석의 변형도를 나타낼 수 있는 좋은 지표로서 사용할 수 있다 암석의 변형도를 결정하기 위해 석영의 파동소광 강도(IWE)를 편광현미경, 디지털 카메라, NIH Image로 측정하였다. 본 연구 에서는 이러한 방법을 이용하여 복잡한 변형을 받은 청산지역일대의 청산반상화강암, 청산복운모화강암, 백록화강암의 변형도를 구하여 청산일대의 변형사를 밝혔다. NIH Image로 측정한 결과, 청산화강암과 백록화강암 사이의 주향이동단층 부근과 청산화강암과 영동층군 사이의 부정합면 부근에서 높은 변형도가 나타났다. 따라서 이 지역의 최근의 주된 변형 요인은 영동분지를 형성한 단층과 청산화강암과 백록화강암 사이에 있는 주향이동단층이다.

• 대기
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• 제17권4호
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• pp.349-364
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• 2007

The main purpose of this study is to examine the sensitivity of the WRF (Weather Research and Forecasting) in the wind field to the steepness of mountains in the case with a strong downslope wind occurred in the Yeongdong province. We conducted WRF simulations for February 13 2006. The initial and boundary data are from the NCEP/NCAR $1^{\circ}{\times}1^{\circ}$ GDAS. Arbitrary terrains of the mountains with a symmetric orography and an asymmetric one with steeper leeward slope, were introduced to examine the sensitivity of the shape of the mountains. The simulation with an asymmetric terrain results in stronger maximum surface wind by about $10ms^{-1}$ than with a symmetric terrain, especially in the narrow region from the peak to ~ 4 km away in the downstream. However, the maximum surface wind speed is weaker by $20ms^{-1}$ than with a symmetric terrain away from the narrow peak region. This indicates that the steeper slope leads to the intensification of downslope wind in the narrower region leeward. In addition, for the simulation with an asymmetric terrain, the strength of wave breaking is greater and the Lee wave is more dominant than for that with a symmetric terrain.

• 품질경영학회지
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• 제28권4호
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• pp.75-98
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• 2000

The purpose of this study is to empirically examine the customers' perceived service quality and response in the field of hotel industry. The subjects of survey for this empirical analyses are limited to the customers of deluxe hotels in Korea; data are collected from the 16 deluxe hotels amongst 27 of its kind in the Seoul, Pusan, Cheju and Kyongju area. SAS package is used for Simple Regression, Multiple Regression and the results are as follows: First, the perceived service quality shows significantly positive effect upon the customers' satisfaction; Second, the customers' perceived service quality shows significantly positive with respect to the customers' response; Third, the customers' satisfaction shows significantly positive regarding the customers' response, and the customers' satisfaction have greater influence upon the customers' response than the customers' perceived service quality; On the basis of the above empirical analyses, I propose the management implication as follows: First, the hotel management staffs should have a close relation with their customers through the customers' positive, and eventually be concemed about improving service quality and customers' satisfaction to maximize the enterprise's performance; Second, the hotel management staffs, to induce and build up the positive customers' response, should have interest in serving high-quality products and service and enforcing the proper price policy.

• The Journal of Korean Physical Therapy
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• 제29권1호
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• pp.27-32
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• 2017

Purpose: Recent electrophysiological studies have shown that the sensorymotor cortex is activated during both actual action excuted by themselves and observation of action performed by other persons. Observation of action based on mirror neuron system can be used as a cognitive intervention to promote motor learning. The purpose of this study was to investigate the brain activity changes during action observation and action execution using EEG. Methods: Thirty healthy volunteers participated and were requested to perform hand action and to observe the video of hand action performed by another person. The EEG activity was evaluated by a method which segregated the time-locked for each condition. To compare the differences between action observation and execution, the Mu suppression and the relative band power were analysed. Results: The results showed significant mu suppression during the action observation and execution, but the differences between the two conditions were not observed. The relative band power showed a significant difference during the action observation and execution, but there were no differences between the two conditions. Conclusion: These results indicate that action execution and observation involve overlapping neural networks in the sensorymotor cortical areas, proposing positive changes on neurophysiology. We are expected to provide information related to the intervention of cognitive rehabilitation.

• 패션비즈니스
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• 제11권5호
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• pp.124-135
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• 2007

To understand tendency of body shapes of Chinese women who reside in Beijing and Shanghai for improving the match of exported clothes to China, this categorizes the bodies by extracting the elements of the objects and understanding body promotion. To categorize the subject by not size factor but form factor, data were compared and analyzed mainly with index based on measurement of the body. This selected specimen as 1381 of Chinese women from 19 to 50 selected in random sampling in Shanghai and Beijing from 23th, June to 7th August in 2004. 1. Chinese women is generally separated in 7.09 parts and upper body including waist shapes round. 2. The elements indicating the women's physical properties are obesity, the size of upper part, front shape, side shape, shoulder and back shape, perpendicular size and lower part length, body shape. 3. The Chinese are categorized by three factors. Normal shape which is not both fat and skinny, records the highest in the ranking.

• 한국안광학회지
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• 제4권2호
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• pp.165-169
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• 1999

시료의 한 부분에 순간적으로 가열하여 시료의 특정 부분의 온도변화를 조사함으로써 시료의 열 확산도를 측정하였다. $Pb_5Ge_3O_{11}$ 단결정의 환산 열 확산도는 trigonal 구조인 $30^{\circ}C$에서는 $0.0117cm^2/^{\circ}C$, curie point 근방인 $178^{\circ}C$에서는 $0.0105cm^2/^{\circ}C$이며 hexagonal 구조인 $180^{\circ}C$에서는 0.0112cm로 각각 나타났다. 이는 $Pb_5Ge_3O_{11}$ 단결정을 같은 열량으로 가열하였을 때, 실온에서 curie 온도쪽으로 갈 때 가열 효과가 적었으며 curie point에서 최소가 되었다가 curie 온도 이상에서는 갑자기 증가하여 일정하게 되었다. 따라서 $Pb_5Ge_3O_{11}$ 단결정의 상전이 용도가 1m 근방임을 확인하였다.

• 한국안광학회지
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• 제8권2호
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• pp.99-103
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• 2003

본 연구에서는 4매의 렌즈로 해상도와 왜곡을 최적화한 렌즈 설계이다. 컴팩트한 광학계를 얻기 위해서 retrofocus 형태의 광학계 대신에 (+)굴절능과 (-)굴절능으로 조합된 telephoto 형태로 구성하였다. 이미지 센서 렌즈계의 설계 사양은 초점거리 8.3mm, F/# 2.8, 그리고 화각은 $54.7^{\circ}$였다. MTF 값은 설계된 물체 높이의 경우 110 lp/mm의 공간주파수에서 0.57 이상으로 나타났다. 설계된 렌즈계는 디지털 스틸 카메라용 광학계에서 요구되는 성능을 충분히 만족하며, 특히 렌즈설계의 간단한 프로파일 특성 때문에 컴팩트한 디지털 카메라와 저비용 설계에 적합하다.

• 한국주조공학회지
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• 제21권6호
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• pp.359-365
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• 2001

The superplastic behavior of whisker reinforced aluminum alloy matrix composites fabricated by squeeze casting as one of high pressure routes was investigated. The preforms of ${\alpha}-Si_3N_4$ and ${\beta}-SiC$ whiskers without any binder as a reinforcement were used. The matrix materials were 2024 and 7075 aluminum alloys. For the purpose of optimum superplastic condition, respectively, the whiskers volume fraction, extrusion temperature, tensile test temperature and initial strain rate were changed. Fracture surface of tested specimens were observed by SEM. By the results, it became possible to produce superplastic composites by applying only a hot extrusion process to composites obtained by the squeeze casting. The superplastic composites developed are ${\alpha}-Si_3N_4w/7075$, ${\alpha}-Si_3N_4w/2024$ and ${\beta}-SiCw/2024$ systems at high strain rate.