• 대한물리의학회지
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• 제18권1호
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• pp.15-24
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• 2023

PURPOSE: This study examined the effects of lowintensity resistance exercise combined with blood flow restriction on muscle activity and muscle fatigue to determine if such a combination may be an alternative to high-intensity resistance exercise in maintaining the muscle mass and strength and preventing degenerative loss of skeletal muscle and to provide basic data for presenting the effectiveness of exercise. METHODS: The interventions were provided for five weeks, four sessions a week, once a day, 60 minutes a session to Experimental group I (n = 13), in which low-intensity resistance exercise was applied by combining blood flow restriction with the biceps curl and experimental group II (n = 12), in which only high-intensity resistance exercise was applied. As a pre-test, the biceps brachii muscle activity and fatigue were measured by surface electromyography, and the hemodynamic variables, such as blood pressure and heart rate, were measured. The post-test was performed identically to the pre-test and compared and analyzed with the pre-test. RESULTS: A significant difference within-group was observed in the biceps brachii muscle activity and fatigue in experimental group I and only in biceps brachii activity in experimental group II. No significant differences were observed between the two groups. CONCLUSION: Since the low-intensity resistance exercise combined with blood flow restriction has similar effects to high-intensity resistance exercise, it is considered an alternative for improving muscle function in groups unable to perform high-intensity resistance exercise.

• The Journal of Korean Physical Therapy
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• 제27권5호
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• pp.339-344
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• 2015

Purpose: The purpose of this study was to determine the effects of high and low resistance exercise using an elastic band on the strength and lymphedema of upper extremity in patients with breast cancer. Methods: Seventeen female patients with breast cancer related lymphedema were randomly allocated to the high (n=9) or low (n=8) resistance exercise group. Both groups participated in the elastic band exercise program three times a week for eight weeks. For the high resistance exercise group (HR), the resistance was gradually increased, while maintaining constant intensity of exercise for the low resistance exercise group (LR). Assessments made include the upper extremity muscle strength and lymphedema before and after training. Results: After the exercise program, the HR showed significantly improved shoulder flexion and elbow flexion strength variation compared to the LR (p<0.05). Upper arm edema rate was significantly decreased in HR (p<0.05), but the difference between the two groups was not significant. Conclusion: These findings suggest that the elastic band exercise helps improve the strength and lymphedema of upper extremity in patients with breast cancer. In particular, high resistance exercise is more effective in improving muscle strength and does not exacerbate lymphedema, rather may improve upper arm edema if it is applied with a low elastic bandage or compression sleeve.

• Imaging Science in Dentistry
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• 제35권4호
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• pp.207-213
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• 2005

Purpose: To classify and describe the characteristic features of MRI of some ameloblastoma variants. Materials and Methods: The MR images, CT images, and panoramic radiographs in 5 cases were retrospectively examined as follows. First, the contents of ameloblastomas were devided into two portions of either solid or cystic components on the basis of MR signal intensities. The signal intensity within the solid or cystic portions was classified as homogeneous or heterogeneous. Next, the characteristic internal feature of the lesion on T1W1 or T2WI was described. The signal intensities were classified into low, intermediate, slightly high, high, and strong high signal intensity. Results: Unicystic lesion showed homogeneous high signal intensity (SI) on T2W2 and the rim enhancement of the surrounding area including the mural nodule and the thick wall except the central portion on Gd- T1W1. Solid type revealed heterogeneous and high SI area with strong high SI area on T2W2. On Gd- T1W1, the area corresponding to the low signal spot on T1W1 and the strong high signal spot on T2W1 showed low SI. Hybrid type showed slightly enhanced capsular structures and low SI for the round bony septa and the areas connecting the mixed and cystic lesions on T2Wl and Gd-T1W1. Conclusion: MRI could easily assess the relationship between the mixed and cystic findings in ameloblastoma.

• The Journal of Korean Physical Therapy
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• 제22권6호
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• pp.71-76
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• 2010

Purpose: The purpose of this study was to examine changes in autonomic nerve responses after low-frequency transcutaneous electrical nerve stimulation (TENS). Methods: Research subjects were 24 students who attend University. Subjects were divided into two groups: 1 = a low intensity group; 2 = a high intensity group. Electrodes were attached to the forearm of the dominant arm and electrical stimuli were administered for 15 minutes. Outcome measures were skin conduction velocity, skin temperature, blood flow, and pulse frequency, each of which was measured a total of 4 times. The data were analyzed using a repeated measures ANOVA. Results: In changes in conduction velocity, the main effect of time variation (in black) was statistically significant. The interaction between time and group main effects was not statistically significant; nor was the difference between the groups. Results showed that skin conduction velocity changed without any relation to group. Conclusions: Low frequency TENS selectively increases skin conduction velocity, which may be helpful for activating sudomotor function regardless of intensity.

• 한국조명전기설비학회:학술대회논문집
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• 한국조명전기설비학회 2003년도 학술대회논문집
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• pp.3-8
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• 2003

Platforms of many railroad stations are crowded with passengers regardless of the time throughout day. But the intensity of illumination of the existing lightening systems are so low enough to make passengers feel inconvenience in using platforms. Consequently there exists high possibility of accidents in platforms of low illumination. Hence, for the safety and convenience of passengers, it is necessary to improve the luminous intensity of lightening system for platforms. This paper points out the problems of existing system and presents the method to improve it.

• 한국해양공학회지
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• 제16권5호
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• pp.80-87
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• 2002

In this study, CT specimens were prepared from spring steel(SUP9) which was used in suspension of automobile for room temperature and low temperature service. We got the following characteristics from fatigue crack growth test carried out in the environment of room temperature and low temperature at $25^{\circ}C$, ­3$0^{\circ}C$, ­5$0^{\circ}C$, ­7$0^{\circ}C$ and ­10$0^{\circ}C$ in the range of stress ratio of 0.05 by means of opening mode displacement. The threshold stress intensity factor range ΔKth in the early stage of fatigue crack growth (Region I) and stress intensity factor range ΔK in the stable of fatigue crack growth (Region II) was decreased in proportion to descend temperature. It is assumed that the fatigue resistance characteristics and fracture strength at low temperature and high temperature is considerable higher than that of room temperature in the early stage and stable of fatigue crack growth region.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2003년도 추계학술대회논문집
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• pp.333-337
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• 2003

The use of reactive shearing structural intensity to place small patches of constrained layer damping material in order to achieve the largest reduction in the radiated sound power of Air-conditioner outdoor unit is described. The normal surface velocity of each panel was measured using a laser doppler vibrometer. Experimental results indicated that patches of constrained layer damping material placed over areas of high reactive structural intensity reduced the radiated sound power significantly more than patches of the same area placed over areas of low reactive structural intensity

• 산경연구논집
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• 제8권7호
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• pp.13-20
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• 2017

Purpose - Performance appraisal has a significant influence on the development of low-carbon tourism distribution. Research design, data, and methodology - Data of this study are collected from 27 provinces (cities) of China. SBM-Malmquist model is used to measure the TFP and its dynamic changes of low-carbon tourism distribution; TOBIT model is used to discuss the factors of TFP of low-carbon tourism distribution. Results - The results show that, there are obvious differences among regional TFP of low-carbon tourism distribution, the average change tends to grow positively in general, and the western region grows fastest on average due to the improvement of technical efficiency and technical progress, while there are technical efficiency improvement but technical regresses in eastern and central regions. The economic scale, economic strength, structure of energy consumption, location quotient and government regulation have a significant positive effect on the TFP of low-carbon tourism; energy intensity, industrial structure and opening degree have a negative effect; investments in fixed assets, intensity of R&D fund and urbanization rate have no significant influence on the TFP of low-carbon tourism. Conclusions - Improving the productivity of low-carbon tourism and reducing regional differences are effective ways to develop low-carbon tourism and enhance tourism competitiveness.

• 한국안광학회지
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• 제19권1호
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• pp.105-109
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• 2014

목적: 본 연구는 낮은 조도에서 1시간 동안 스마트폰을 시청 한 이후 시력변화와 NIBUT를 비교하였다. 방법: 20대(평균나이 $20.7{\pm}2.4$세)의 안질환이 없고 건강한 눈을 가진 50명(남자 22명, 여자 28명)을 대상으로 실험을 하였다. 낮은 조도(0 lx)에서 스마트폰(Galaxy 2, Samsung, KOREA)을 시청 전과 한 시간 시청 후의 타각적 굴절이상도 검사, 원거리 교정 시력과 NIBUT를 측정하였다. 타각적 측정은 Auto-chart Project(CP-1000, Dongyang, Korea), Phoropter(VT-20, Dongyang, Korea), Auto refractor-keratometer(MRK-3100, Huvitz, Korea)를 이용하였다. 결과: 낮은 조도에서 스마트폰을 시청하기 전과 한 시간 시청 후의 굴절이상도의 변화는 $-3.20{\pm}2.00$ D에서 $-3.38{\pm}2.00$ D로 변화했고(p=0.006), 원거리 교정시력의 변화는 $0.93{\pm}0.08$에서 $0.91{\pm}0.10$으로 변화했으며(p=0.000), NIBUT의 변화는 $10.48{\pm}7.00$ 초에서 $10.29{\pm}6.47$ 초로 변화했다(p=0.761). 결론: 낮은 조도에서 스마트폰을 지속적으로 시청하는 것은 일시적인 원거리 시력의 변화를 초래하였고, 적절한 휴식은 원거리 시력과 눈물 안정성에 미치는 영향을 줄여줄 것으로 사료된다.

• Journal of Microbiology and Biotechnology
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• 제12권3호
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• pp.457-462
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• 2002

Low Electromagnetic Field (EMF) intensity in the range of $1{\mu}T\;to\;10{\mu}T$(Tesla) was found to enhance the growth of CHO cells and the production of tPA in batch and perfusion cultivations. At $1{\mu}T\;intensity,\;1.3{\times}10^7$ viable cells/ml of maximum cell density and 80 mg/l of maximum tPA production were obtained in batch cultivation, compared to $2.8{\times}10^6$ viable cells/ml and 59 mg tPA/1 in unexposed case (control). A similar trend was observed in the perfusion process, where it was possible to obtain $1.2{\times}10^7$ viable cells/ml of maximum cell density and 81 mg tPA/l of maximum tPA production by more than 80 days of cultivation. However, there was not much difference between $1{\mu}T\;and\;10{\mu}T$ in perfusion cultivation, possibly due to better environmental growth conditions being maintained by continuous feeding of fresh medium into the reactor. On the contrary, both cell growth and tPA production were severely inhibited at higher than 1 mT intensity, showing no growth at 10 mT exposure. Specific growth rate was linearly correlated to specific tPA production rate at $1{\mu}T$EMF intensity, which represents a partially growth-related relationship. It was also found that a large amount of $Ca^2+$ was released at low EMF intensity, even though the cell growth was not much affected. Low EMF intensity significantly improved both cell growth and tPA production, and tPA production seemed to be more affected than the cell growth, possibly due to the changes of cell membrane characteristics. It can be concluded that the elaboration of EMF intensity less than $10{\mu}T$ could improve cell growth and tPA production, but mainly tPA secretion through batch or perfusion process in a bioreactor.