• The Journal of Korean Physical Therapy
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• 제18권3호
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• pp.37-45
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• 2006

Purpose: This study analyzed changes in spinal neuron and action potential of motor unit depending on voluntary contraction on spinal neuron adaptation. Methods: It selected 80 university students in their twenties and divided into experimental groups of 25% MVIC (I), 50% MVIC (II), 75% MVIC (III) and 100% MVIC (IV) depending on maximum voluntary isometric contraction (MVIC) and performed isometric exercise of plantar flexor muscle to each experimental group with given contraction for 20 times. It measured Mmax, H/Mmax, Hmax latency, V/Mmax, V wave latency before and after exercise, compared method and volume of contraction. Results: H/Mmax ratio showed significant difference in comparison among groups (p<0.01) and there was difference in I and IV groups. V/Mmax ratio showed significant difference in comparison among experimental groups (p<0.05) and there was difference in I and IV groups. When voluntary contraction level was maximum, changes were greatest. However, no significantly difference was to Mmax, H latency and V wave latency. Conclusion: These results suggest that amplitude changes of voluntary contraction level, spinal neuron and supra-spinal neuron had a dose connection that the more contraction level, the better central activation seem to decrease highly for a short time.

• Journal of the Korean Wood Science and Technology
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• 제23권2호
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• pp.47-54
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• 1995

This study was to measure the properties of logs and classify them by non-destructive methods. The purpose of this experiment was focused at mensurability of logs by non-destructive methods. The non-destructive instrument, Stress-Wave Timer 239A which was made by Metriguard in U.S.A., was used. The stress wave velocities of log's cross direction were measured and compared with three different methods; 1. with hammer, 2. with hammer and D.B.H. meter, 3. with manufactured instrument. Number of used logs were seven logs, which were classified by naked eye into six groups; very severe rot, severe rot, mild rot & knot, mild rot & check, mild rot, sound log, and in diameter were into three groups; large(57.4cm), medium(36~41.2cm), small(28.9cm) log. The results, which were classified by mensurability with non-destructive methods, were followed; 1. The stress wave velocities were very different between rot and sound log. So it meant the possibility of mensurability of logs by non-destructive method even if high standard error. 2. The stress wave velocities decreased with checks more than with rots, which meant the checks affected speeds more. 3. The stress wave velocities increased with knot. 4. The velocities with manufactured instrument showed lower standard error, so more accurate results than other methods. Especially the required labour decreased from 3~4 to 2 persons. 5. Finally, the mensurability showed more accurate results and made the classification of logs scientific.

• 한국환경보건학회지
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• 제27권4호
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• pp.73-78
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• 2001

Hair will be persuit of beautifulness of human being in various permanent wave by many kinds of its drugs. Skin is based upon the hair which enroll the body of high living animals and have multiple membrane structure In this study used rat the effects of commercial permanent wave products to skin which are composed with L- cysteine and bases Results are as follow: the content of penetration 4 hors later with steady state and no significant changeable after 20 hours later. In cysteine groups, lag time and permeability coefficient of healthy skin is 2.22hr and 0.13$\mu\textrm{g}$/㎥ hr, lag time and permeability coefficient of old skin is 4.01 hr and 0.108 $\mu\textrm{g}$/㎥ hr . In conclusion of study lag time and permeability coefficient in old skin and wounded skin are faster than healthy skin. We notified that fine rinkle and rash of skin were changeable in the case of treating with permanent wave drugs than normal skin.

• Smart Structures and Systems
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• 제19권4호
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• pp.415-429
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• 2017

This paper focuses on the impact of the wave passage effect on the long-span bridge. In order to make the wave passage effect more obvious, ground motion samples are selected from the near-fault ground motion of the 1999 Chi-Chi earthquake and an arch bridge with a 280m main span is selected as a bridge sample. The motion ground samples are divided into two groups according to the characteristics of near-fault. A sequence of fragility curves is developed. It is shown that the seismic damage is increased by the wave passage effect and the increase is more obvious in the near-fault ground motion.

• 대한암한의학회지
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• 제26권1호
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• pp.29-37
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• 2021

Objectives: The purpose of this study is to examine whether heart rate variability (HRV) and pulse wave of cancer patients can be used as indicators of their health status and prognosis. Methods: We retrospectively compared HRV, pulse wave and body mass index (BMI) of cancer patients and healthy individuals who visited W hospital from November of 2020 to October of 2021. Results: As a result of comparing HRV and pulse wave parameters between cancer patients and healthy subjects, among HRV indices, mean heart rate (MHR), standard deviation of normal to normal (SDNN) and total power (TP), very low frequency (VLF) showed significant differences between two groups. Cancer patients' pulse wave parameters showed more rapid and superficial than that of healthy subjects. Also, cancer patients weighed less and had lower BMI. Conclusion: For increased MHR, decreased SDNN, rapid and superficial pulse wave can be indicators of poor prognosis of cancer patients, keep monitoring HRV and pulse wave can help to manage patients efficiently.

• Restorative Dentistry and Endodontics
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• 제23권1호
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• pp.346-356
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• 1998

The purpose of this study was to evaluate the sealing ability of various canal filling methods. Palatal roots of ninety extracted human maxillary molar teeth were resected at cementoenamel junction. Eighty of them were randomly assigned to four experimental groups, ten were served as positive and negative controls. All canals were prepared to # 40 using Profile. Experimental groups were obturated by lateral condensation technique, Thermafil technique, Continuous Wave of Condensation Technique, and down-pack & back-fill technique of Obtura-II, each with root canal sealer. Control groups were not obturated. Teeth were immersed in resorcinol-formaldehyde resin for 5 days at $4^{\circ}C$, and the resin was allowed to polymerize completely for 4 days at room temperature. Teeth were then ground horizontally at 1.5mm(level 1), 2.5mm(level 2), 3.5 mm(level 3) from the anatomical apex and examined with a stereomicroscope at ${\times}40$ magnification. The gap between the canal wall and the filling material, which was filled with the resin, was measured at each of the three levels. Each ratio of leakage was obtained by calculating the ratio of the area of the resin to the total area of the canal and was analyzed statistically (Rank-sum test). The results were as follows : 1. At the level 1, there was the greatest leakage in the Thermafil group and Obtura-II group, and the difference between the Obtura-II group and Continuous Wave of Condensation Technique group was statistically significant(p<0.05). 2. At the level 2, there was the least leakage in the Continuous Wave of Condensation Technique group, but there was no statistically significant difference between each group (p>0.05). 3. At the level 3, there was no statistically significant difference between each group(p>0.05).

• 동의생리병리학회지
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• 제35권6호
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• pp.274-279
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• 2021

This study was conducted to find objective diagnostic indicators for the Eight Principle Pattern Identification using a pulse wave analyzer. Typology Complexion Pulse and Symptom data from 500 women over the age of 18 were used. Five experts made a diagnosis of Eight Principle Pattern Identification and divided the subjects into 'Yin-Yang', 'Exterior-Interior', 'Cold-Heat', 'Deficiency-Excess' groups. Their pulse waves were measured in the left and right radial arteries, and it was investigated whether there was a significant difference between groups in the pulse wave parameter values. 'Yin' group showed a significantly lower value in the left radial artery for Ener, Emin, EIX, T4T, T4TT parameters and in the Right for T2, T2T, T5. The Vmag, As and Ad parameters were significantly different between the 'Exterior' and 'Interior' groups. 'Heat' group showed a significantly higher value in the right radial artery for RAI/t parameter. 'Deficiency' group showed a significantly higher value in the right radial artery for W, Angl parameters. Through this study, significant pulse wave parameters were found, and they can be used as objective diagnostic indicators for Eight Principle Pattern Identification.

• Restorative Dentistry and Endodontics
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• 제46권2호
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• pp.28.1-28.10
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• 2021

Objectives: This study evaluated the effect of repeated uses and autoclaving in the instrumented area, fracture resistance, and time of instrumentation of thermally treated nickel-titanium reciprocating systems. Materials and Methods: Two hundred simulated canals were instrumented using Reciproc Blue and WaveOne Gold. Each file was used up to 10 times or until fracture. The instrumented area was measured in pre- and post-operative images, using ImageJ software. Kaplan-Meier survival analysis evaluated the number of uses of instruments before fracture. Instrumented area and time of instrumentation were analyzed by Mann-Whitney U test and Kruskal-Wallis. Correlations among the number of uses and instrumented area were measured. The level of statistical significance was set at p < 0.05. Results: Reciproc Blue presented a higher estimated number of uses in comparison with WaveOne Gold (p = 0.026), but autoclaving did not affect the resistance to fracture of instruments (p > 0.05). The instrumented area was different among the evaluated groups (p = 0.039), and the instrumented area along the uses of both tested instruments was reduced. With the time of instrumentation, there was also a significant difference among the evaluated groups; the groups without sterilization cycles were faster, in comparison to those submitted to autoclaving (p = 0.010). Conclusions: Reciproc Blue was more resistant than WaveOne Gold, suffering later fracture. Additionally, the sterilization cycles did not influence the estimated number of uses of thermally treated reciprocating instruments, but the instrumented area of root canals was reduced along with the repeated uses of both instruments.

• 경영과정보연구
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• 제36권2호
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• pp.21-35
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• 2017

1990년대 이후 중국에서부터 시작된 한류는 전 세계적인 현상으로 자리매김하고 있다. 그러므로 최근 외국인 관광객 증가 흐름을 살펴보았을 때 방한 수요를 결정하는 거시적인 요인 외에 한류현상도 중요한 영향을 미치고 있음을 알 수 있다. 또한 방한 수요와 관련한 기존의 연구들이 연령별 차이를 두지 않고 전 세대를 포괄하거나 특정 세대만을 대상으로 분석하고 있다. 그러나 연령에 따라 한류에 영향을 받는 정도가 다르며 따라서 한류로 인한 방한수요가 연령별로 차이가 존재한다 할 수 있다. 본 연구는 한류가 외국인 관광객 방한에 미치는 영향을 분석하기 위해 한류지수를 이용하고 분석대상을 연령별로 세분화하여 실증분석을 시행한다. 분석 결과에 따르면 한류에 쉽게 영향을 받는 20대 이하가 한류로 인한 방한이 가장 많이 이루어지고 있다. 주목할 만한 사실은 50대 이상의 한류지수 추정계수가 30~40대 보다 높게 나왔다는 점이다. 이는 부모세대가 한류에 영향을 받은 어린 자녀와 함께 한국으로의 동반 입국이 이루어지고 있음을 의미한다. 본 연구를 통해 방한 선택에 있어 한류의 영향이 연령별로 차이가 존재하고, 세대별로 적절한 관광 마케팅 전략이 필요한 것을 알 수 있다. 예를 들어 모녀여행 상품처럼 한류에 영향을 받은 20대 이하의 자녀뿐만 아니라 함께 방한한 부모세대가 같이 즐길 수 있는 관광 상품을 개발해야 할 것이다. 또한 상대적으로 한류로 인한 방한이 적은 30~40대의 경우 다른 세대보다 본인에 대한 투자가 많은 세대이므로 한류를 통해 소개된 한국의 뷰티, 패션, 문화, 레저 등과 연계된 관광 상품을 개발할 필요가 있다.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2003년도 학술발표회논문집(2)
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• pp.1051-1054
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• 2003