• Journal of Acupuncture Research
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• 제29권4호
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• pp.25-34
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• 2012

Objectives : This study was conducted to investigate the effects of fixed-intensity and varied-intensity electroacupuncture in pain and sensory threshold concerning parameters visual analogue scale(VAS), brief pain inventory(BPI) and quantitative sensory testing(QST), among chronic tension headache patients. Methods : Thirty patients with chronic tension headache were randomly assigned to three groups and received different kinds of electroacupuncture at $ST_{36}$ and $ST_{37}$. Group A received fixed-intensity electroacupuncture(fixed-EA), group B received varied-intensity electroacupuncture (varied-EA), and group C received only acupuncture treatment without electrical stimulation as a control group. The intervention was given three times per week, and continued in two weeks. All the experiments were conducted blindly. Results : Fixed-EA group showed a significant decrease of VAS and BPI compared to the baseline measurement, while both varied-EA and control group did not. Of the parameters of QST, subtraction of heat pain threshold(HPT) and cold pain threshold(CPT) slightly increased in all groups, but this was not significant. Conclusions : These results suggest that fixed-EA reduce pain and improve quality of life in patients with chronic tension headache and that acupuncture may regulate patient's pain sensitivity through changing sensory threshold.

• Journal of Acupuncture Research
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• 제28권2호
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• pp.107-116
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• 2011

Objectives : This study was performed to investigate the effects of fixed-intensity and varied-intensity electroacupuncture on heart rate variability in healthy people with stress task. Methods : Forty healthy subjects were randomly assigned to either group A or group B or C. Group A received fixed-intensity electroacupuncture(F-EA) at $ST_{36}$ and $ST_{37}$. After 1 week wash out period to prevent overlapping residual effects, they received varied-intensity electroacupuncture(V-EA) in which the intensity was changed every two minutes based on individual heart rate variability at the same points. Group B received the treatments in reverse order. Group C received no intervention as a control group. Results : Control group showed a significant increase of LF and LF/HF during the 2nd working memory task, while both F-EA and V-EA did not. In addition, V-EA showed a significant increase of HF during 2nd rest while F-EA did not. Conclusions : These results suggest that F-EA and V-EA can inhibit sympathetic activation more than control group and that V-EA can enhance parasympathetic activation more than F-EA.

• 한국윤활학회:학술대회논문집
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• 한국윤활학회 1999년도 제29회 춘계학술대회
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• pp.297-302
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• 1999

Finite element analysis is peformed about the crack propagation in half-space due to sliding contact. The analysis is based on linear elastic fracture mechanics and stress intensity factor concept. The crack location is fixed and the friction coefficient between asperity and half-space is varied to analyze the effect of surface friction on stress Intensity factor for horizontal crack. The crack propagation direction is predicted based on the maximum range of shear and tensile stress intensity factor.

• 한국음향학회:학술대회논문집
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• 한국음향학회 1994년도 FIFTH WESTERN PACIFIC REGIONAL ACOUSTICS CONFERENCE SEOUL KOREA
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• pp.879-884
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• 1994

This paper reports on several experiments carried out to find the effects of intensity difference on duration discrimination in pairs of pure tones. Pure-tone signals were presented with the modification of amplitude and duration. Duration-discrimination thresholds for the musical tones and the signals that were varied in amplitude were investigated together with those of the fixed signals. From the results, it was found that the duration discrimination tasks are affected by an intensity difference of 20 phons.

• Journal of Magnetics
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• 제20권3호
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• pp.290-294
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• 2015

To investigate the effects of alternating magnetic field intensity and stimulation time on the proliferation of human breast cancer cells (BT-20), we cultured the cells under a magnetic field with a saw tooth waveform of 2 kHz. The field intensities varied from 3 to 7 mT, and the stimulation time varied from 24 to 72 hours. Cell proliferation decreased dramatically to 40% during magnetic stimulation for 72 hours at 5 mT. However, the cells were not affected by a strong magnetic field of 7 mT. The p-values obtained using statistical package for social science software were below 0.05 for 5-7 mT. This means that the results have statistical significance. However, it is difficult to explain our results based on the physiology of cell membranes, which have various ionic flows at ion channels.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2004년도 추계학술대회 논문집 전기물성,응용부문
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• pp.147-149
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• 2004

Inductively coupled plasma is commonly used for electrodeless lamp due to its ease of plasma generation. Optical characteristics significantly depend on the RF power and gas pressure of the plasma. This paper describes the measurement of spectrum as a function of RF power and gas pressure with a goal of finding optimal operating conditions of the electrodeless lamp. The gas pressure was varied from 10 [mTorr] to 100 [mTorr] and the RF power was varied from 10 [W] to 120 [W]. It was found that the intensity of wavelength tends to be decreased when argon pressure is increased, and the intensity of wavelength is increased as RF power is increased.

• 한국미생물·생명공학회지
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• 제19권4호
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• pp.377-382
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• 1991

우지를 lipase에 의해 지방산과 글리세린으로 분해하는 반응을 액상 및 고상에서 수행하였다. 올리브유를 기질고 lipase OF 360(일본 메이토사 제품)의 특성을 조사한 결과 최적 pH는 6, 최적 온도는 $37^{\circ}C$이었다. 우지를 기질로 액상 효소반응을 수행한 결과는 물사용량 80 wt/wt, 온도 $37^{\circ}C$, 효소사용량 200unit/g tallow 조건에서 93의 가수분해율을 얻을 수 있었다.

• 대한기계학회논문집B
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• 제23권2호
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• pp.166-174
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• 1999

The flow characteristics of 2-valve and 4-valve cylinder heads with various blocked-valve were experimentally investigated in a steady flow rig. Effects of the blocked-valve configurations on flow coefficient, swirl and tumble intensity are studied. Compared to the conventional valve, the blocked valve in both cylinder heads have the much lower flow coefficient and the much higher intensity of swirl and tumble. Under the same size of blockage, the value of flow coefficient and swirl(or tumble) intensity were varied according to the position of blockage. Throughout these steady flow test the optimized positions of blockage in both cylinder heads were determined.

• Tribology and Lubricants
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• 제16권5호
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• pp.373-380
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• 2000

Finite element analysis is performed on the subsurface crack propagation in brittle materials due to sliding contact. The sliding contact is simulated by a rigid asperity moving across the surface of an elastic half-surface containing single and multiple cracks. The single crack, coplanar cracks and parallel cracks are modeled to investigate the interaction effects on the crack growth in contact fatigue. The crack location is fixed and the friction coefficients between asperity and half-space are varied to analyze the effect of surface friction on stress intensity factor for horizontal cracks. The crack propagation direction is predicted based on the maximum range of shear and tensile stress intensity factors. With a coplanar crack, the stress intensity factor was increased. However, with a parallel crack, the stress intensity factor was decreased. These results indicate that the interaction of a coplanar crack increases fatigue crack propagation, whereas that of a parallel crack decreases it.

• 음성과학
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• 제5권1호
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• pp.49-62
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• 1999

This study is concerned with the educational program Visual Analysis Tool (VAT) for sound development for foreign intonation using personal computer. The VAT can run on IBM-PC 386 compatible or higher. It shows the spectrogram, waveform, intensity and the pitch contour. The system can work freely on either waveform zoom in-out or the documentation of measured value. In this paper, intensity and pitch contour information were used. Twelve French sentences were recorded from a French conversational tape. And three Korean participated in this study. They spoke out twelve sentences repeatly and trid to make the same pitch contour - by visually matching their pitcgh contour to the native speaker's. A sentences were recorded again when the participants themselves became familiar with intonation, intensity and pauses. The difference of pitch contour(rising or falling), pitch value, energy, total duration of sentences and the boundary of rhythmic group between native speaker's and theirs before and after training were compared. The results were as following: 1) In a declarative sentence: a native speaker's general pitch contour falls at the end of sentences. But the participant's pitch contours were flat before training. 2) In an interrogative: the native speaker made his pitch contours it rise at the end of sentences with the exception of wh-questions (qu'est-ce que) and a pitch value varied a greath. In the interrogative 'S + V' form sentences, we found the pitch contour rose higher in comparison to other sentences and it varied a great deal. 3) In an exclamatory sentence: the pitch contour looked like a shape of a mountain. But the participants could not make it fall before or after training.