• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.33 no.1
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• pp.48-53
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• 2005

The purpose of this investigation is to explore the possibility of using artificial mechanical means for excitation of shear layers with application in swirling jet mixing enhancement. For this purpose, a mechanical excitation device was designed and fabricated. The major system components consist of two subsonic nozzles, one swirl generator, and the excitation device. The experiments were carried out at various helical excitation modes; i.e., m=+0, m=$\pm$1, m=$\pm$2, m=$\pm$3, and m=$\pm$4. Axial mean velocity measurements were made with plane and helical wave excitation using a hot-wire anemometer. The results are compared with the baseline (plane-wave excitation) at various helical modes. The acquired data is presented in 3-D mesh plots and 2-D contour plots. It was observed that new device was effective in excitation of the helical instability waves and resulting in mixing enhancement of the swirling jet.

• The Journal of the Korea Contents Association
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• v.10 no.4
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• pp.257-264
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• 2010

Though existent a transcranial magnetic stimulation makes various treatment and diagnostic sine waveform of fixed stimulation pulse, there is limitation. In this research, because strength, pulse width, pulse pattern required in treatment and diagnostic introduce other Cockroft-Walton circuit and half bridge inverter frequency and voltage variable become new device propose wish to. Have more advantages than existing device. First, do not have high voltage transformer. Second, switching loss can be less, and control output energy precisely. Three, stimulation strengths, pulse width, pulse pattern are various. As a result, sought special quality and an experiment that is improved applying inverter and cockroft - Walton circuit is half bridge inverter that do not use transformer.

• Journal of the Korean Applied Science and Technology
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• v.37 no.4
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• pp.755-761
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• 2020

The purpose of this study was to investigate the effects of balance board and whole-body vibration stimulator application on body muscle activities during static squat motion. Twenty adult males(age, 21.90±0.36 years; height, 174.30±1.09 cm; body mass, 66.50±1.00 kg; and BMI, 21.90±0.31 kg/㎡) were participated in this study as subjects. Three types' static squat motions were performed(basic static squat motion, BSSM; static squat motion with balance board, SSBB; static squat motion with whole-body vibration stimulator, SSVS). We measured the right side's body muscle activities of the rectus abdominis(RA), internal oblique(IO), external oblique(EO), rectus femoris(RF), vastus lateralis(VL), and vastus medialis(VM). The research findings were as follows. There was a significant higher RA, IO, and EO muscle activity of SSBB and SSVS(p=.001, p=.004, p=.000). And RF, VL, and VM muscle activities were greatest during SSVS(p=.000). These findings are expected to serve as references for static squat motion applications in training programs for body muscle strengthening.

• Clean Technology
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• v.20 no.3
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• pp.226-231
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• 2014

This study presents a micromolding for the synthesis of Janus particles with reconfigurable shape by pH stimuli. First, we use acrylic acid (AA) as pH responsive monomer in the hydrophilic part and trimethylolpropane triacylate (TMPTA) in the hydrophobic part, respectively. The change of acidity in solvent induces the swelling of hydrophilic part in the Janus particles. The pH-responsive Janus particles show different swelling ratio of hydrophilic part in according to composition of acrylic acid in diverse range (0-70% v/v) and pH (3-11). As the concentration of acrylic acid in the hydrophilic part and environmental pH increase, the hydrophilic part in the Janus particles is proportionally swelled. Second, we fabricate novel type of Janus particles with two different hydrophilicities. As a proof of concept, we have applied acrylic acid (AA) and 2-(dimethylamino)ethyl methacrylate (DAEMA) into each part because the monomers provide reverse responsive activity. As expected, these Janus particles show different shape anisotropies with reconfigurable property in accordance with the polarity of each part at same acidity of environmental solvent. We envision that the stimuli responsive Janus particles have a wide application from fundamental science to diagnostic apparatus.

• Journal of rehabilitation welfare engineering & assistive technology
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• v.7 no.2
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• pp.13-18
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• 2013

In this paper design a 8 bit Current Steering D/A Converter for stimulating neuron signal. Proposed circuit in paper shows the conversion rate of 10KS/s and the power supply of 3.3V with 0.35um Magna chip CMOS process using full custom layout design. It employes segmented structure which consists of 3bit thermometer decoders and 5bit binary decoder for decreasing glitch noise and increasing resolution. So glitch energy is down by $10nV{\bullet}sec$ rather than binary weighted type DAC. And it makes use of low power current stimulator because of low LSB current. And it can make biphasic signal by connecting with Micro Controller Unit which controls period and amplitude of signal. As result of measurement INL is +0.56/-0.38 LSB and DNL is +0.3/-0.4 LSB. It shows great linearity. Power dissipation is 6mW.

• Journal of Periodontal and Implant Science
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• v.37 no.sup2
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• pp.311-323
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• 2007

Receptor activation of nuclear factor ${\kappa}$ B ligand (RANKL)은 파골세포의 분화와 기능에 중요한 역할을 하는 단백질로 이들 물질의 조절에는 p38 MAP kinase가 관여한다. 그러나 치주인대 섬유모세포에서 RANKL 발현 시 p38 MAP kinase의 역할은 잘 알려져 있지 않다. 이에 이번 연구는 마우스 치주인대 섬유모세포의 $IL-1{\beta}-induced$ RANKL 발현과정에서 p38의 역할을 규명하고자 하여 다음과 같은 결과를 얻었다. 마우스 치주인대 섬유모세포에 $IL-1{\beta}$ (1ng/ml)의 자극은 수용성 RANKL의 합성을 증가시켰다. 수용성 RANKL의 합성은 p38 MAP kinase 억제제인 SB203580에 의해 농도 의존적으로 억제되었으나 다른 MAP kinase 억제제인 SP600125, JNK 억제제와 PD98059, ERK 억제제에 의해서는 수용성 RANKL의 합성이 조절되지 않았다. NF-kB 억제제에 의해서도 수용성 RANKL의 합성이 억제되지 않았다. RANKL 유전자의 발현은 $IL-1{\beta}$로 자극 시에는 대조군에 비해 약 5배의 발현 증가를 보였으나 SB203580으로 전처치 시 $IL-1{\beta}$ (1ng/ml)로 자극시보다 약 1.5배의 감소를 보였다. 그러나 SP600125, PD98059, 및 NF-kB 억제제로 전처치한 경우에는 $IL-1{\beta}$로 자극한 경우와 비슷한 수준을 보였다. $IL-1{\beta}$로 자극 시 RANKL 유전자의 반감기가 90분 이었으나 SB203580로 전처치 후 $IL-1{\beta}$로 자극 시 RANKL 유전자의 반감기는 60분으로 감소하였다. Cycloheximide 전처리 시 SB203580에 의한 RANKL 유전자 발현 억제가 관찰되지 않았다. 단백질 분석결과 p38 MAP kinase의 인산화 활성은 30분까지 증가하였으나 그 이후 감소하여 2시간째에는 그 발현이 미약하였다. SB203580로 전처치 후 $IL-1{\beta}$로 자극 시 p38 MAP kinase의 인산화 활성이 감소하였다. 이상의 결과는 p38 MAP kinase가 RANKL 유전자 조절에 중요한 역할을 담당하고 있음을 시사한다.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.13 no.6
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• pp.1157-1166
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• 2009

The effect of acupuncture that occurs at Meridians, can not be defined by western science. But we can find out the electrical effects when acupuncturing by measuring the charges meridians electric potential. So instead of using a needle to acupuncture, we used a electromagnet to give the same effect. We stimulated the meridians, with a electromagnet. Then we observed the pattern of the meridians potential, that occurred at ST-39 and ST-37. After doing clinical experiments with the acupuncture stimulation and the electromagnet stimulation. We found out the acupuncture stimulation and the electromagnet stimulations electric waves were similar. From this result, we knew it was possible to give similar effects to acupuncture stimulation by using electromagnets.

• Proceedings of the Korean Society for Emotion and Sensibility Conference
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• 1998.04a
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• pp.75-80
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• 1998

본 연구는 얼굴근전도(facial EMG)가 다양한 시각자극에 의해서 유발된 감성을 평가할 수 있는가를 알아보고자 하였다. 특히 감성의 차원중 각성-이완차원에서의 차이를 얼굴근전도를 이용하여 객관적으로 측정할 수 있는가를 알아보았다. 사용된 자극은 15개의 시각자극이었다 . 각각의 자극은 30초씩 무선적으로 제시되었고, 각 자극의 제시사이마다 120초씩의 휴식기를 두었다. 매 자극제시후 피험자는 제시된 자극에 대해 각성-이완의 정도를 주관적으로 평가하였다. 실험참가자는 25명의 여자대학생이었으며, 왼쪽이마의 추미근(corrugator muscle)과 빰의 관골근(zygomatic muscle)의 얼굴근전도를 측정하였다. 측정된 얼굴근전도에 대해서 절대값을 취해 면적을 구하였다. 최대 각성(the most arousing stimulus), 최소 각성(the least arousing stimulus), 최소이완(the least relaxing stimulus), 최대이완(the most relaxing stimulus)이라고 피험자들마다 주관적으로 평가한 가극에 대한 얼굴근전도를 비교.분석하였다. 그 결과 이마의 추미근이 각성과 이완감성의 차이를 변별할 수 있었다. 즉 각성감성을 느낄수록 이마의 추미근의 활동이 증가함을 보였다. 또한 최대각성감성을 느낄때 이마의 추미근의 활동이 증가함을 보였다. 결론적으로, 얼굴근전도가 다양한 시각자극에 의해 유발된 감성의 각성-이완차원을 측정할 수 있는 좋은 지표가 될수 있음을 나타낸다.

• Journal of Biomedical Engineering Research
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• v.19 no.5
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• pp.539-546
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• 1998

The purpose of this study is to estimate human emotion quantitatively under colors and music stimuli and to examine the for correlation between color and music sensibility. Physiological signals(electroencephalogram, electrocardiogram, Galvanic skin conductivity and respiration rate) were measured to compare color with music sensibilities. The personality of the subject were investigated using factor analysis and semantic differential method of 20 items(7 interval scaled). The results showed that red, yellow and violets color provoked active and exciting senses mainly as dance, rock and blues music. While blue, cyan and pink colors ware involved in tranquil and resting emotions deeply as classic and ballade music.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2000.10a
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• pp.21-22
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• 2000

생물의 특성 중 하나는 외부나 내부의 자극에 대하여 반응한다는 것이다. 이러한 환경의 변화를 감각기관에서 수용하여 그 환경의 변화에 적절하게 대응하는데 이러한 반응은 작게는 운동, 크게는 행동이라는 형태로 나타난다. 동물에 있어서 이와 같이 자극에 대하여 특이한 반응행동을 일으키는 성질들을 주성(Taxis)이라 한다. 주성에는 자극에 따라 주광성, 주촉성, 주류성, 주온성 등이 있으나 어업에 있어서 가장 광범위하게 이용하고 있는 것이 어류의 주광성이라 할 수 있다. (중략)