• Journal of Advanced Technology Convergence
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• v.2 no.1
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• pp.23-31
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• 2023

This study was described about the EEG response results of tea tree oil fragrance for the development of functional shampoo additives. In the case of experimenters (1) the intensity change of the right brain alpha wave in electroencephalographic (EEG) response was increased after inhalation of the tea tree oil fragrance. (2) the change of physical tension and stress both the left brain and the right brain in EEG response showed a tendency to decrease after inhalation compared to before inhalation of the tea tree fragrance. (3) the mental distraction and stress was decreased after experimenters inhales the tea tree oil fragrances. These means the tea tree fragrances have both mental stability and stress relief. From above results, we prepared the functional shampoo additives with tea tree oil, and the we determined the alpha wave in EEG response after the functional shampoo additive fragrance for experimenters. As results, (4) the alpha wave intensity in left and right brain was significantly decreased after inhaling the functional shampoo additives fragrance. (5) physical tension and stress changes were decreased after inhalation of functional shampoo additive fragrance. (6) mental distraction and stress changes were also decreased after inhalation of functional shampoo additive fragrance. , From above results, the functional shampoo additives could be used as physical and mental relievers. Furthermore, the functional shampoo additives have the effects of scalp calming when the experimenter was treated shampoo with the functional shampoo additives.

• Food Engineering Progress
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• v.15 no.2
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• pp.122-129
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• 2011

In this study, discrimination of salted cuttle fish and salted mitra squid was carried out using electronic nose based on mass spectrometer. Intensities of each fragment from salted cuttlefish by electronic nose were completely different from those of salted mitra squid. Each sample was analyzed, and discriminant function analysis (DFA) was used for the discrimination of similar products. DFA plot indicated a significant separation of each salted cuttlefish and mitra squid ($r^2$= 0.8789, F= 162.13). Electronic nose based on mass spectrometer could be used as an efficient method for discrimination of Economically Motivated Authentication (EMA) foods.

• Journal of Energy Engineering
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• v.4 no.2
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• pp.261-269
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• 1995

본 연구에서는 밀폐형 2상 열사이폰의 액체 Pool에서 발생하는 핵비등현상과 유동영역에 대해 가시화 방법으로 연구하였다. 실험용 열사이폰은 스텐레스와 유리관을 이용하여 제작하였으며, 열공급은 증발부 주위에 설치된 유도 가열용 코일에 고주파를 가함으로써 스텐레스 외면에 발열이 일어나도록 하였다. 이에 따른 결과는 다음과 같다. 실험용 열사이폰은 고주파 가열등 열사이폰의 작동성능을 저해하는 여러 요인들이 포함되어 있었으나, 실험결과 이러한 문제는 실험 내용에 영향을 미칠만큼 크게 나타나지 않았다. 열속과 상당압력의 범위는 각각2$m^2$, 0.1

• Magazine of the Korea Concrete Institute
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• v.10 no.5
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• pp.177-187
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• 1998

최근 국내에서 해양 구조물, 장대 교량의 하부구조물, LNG저장탱크 등 매스콘크리트의 증가추세에 따라 구조물의 고내구성과 관련하여 시멘트의수화열에 의한 온도균열의 발생을 최소화 시킬 수 있는 3성분계 혼합형 저발열시멘트가 개발되어 실 구조물의 적용단계에 있으나, 저발열시멘트가 개발되어 실 구조물의 적용단계에 있으나 저발열시멘트의 특성에 대한 전반적인 연구보고가 국내에서는 미진한 실정이다. 따라서 본 연구에서는 3성분계 혼합형 저발열시멘트의 특성 및 코\ulcorner리트의기초물성을 1종 보통포틀랜트 시멘트, 5종 내황산염시멘트, 슬래그시멘트와 비교하였다. 글 결과 저발열 콘크리트의 찹축강도는 초기재령에서 강도발현률이 적은 반면 장기강도발현률은 상당히 큰 경향을 보였다. 또한 수화열은 1종시멘트를 사용한 콘크리트에 비하여 1/3~1/2정도로 매스콘크리트의 수화열을 대폭적으로 저감시킬 수 있을 뿐만 아니라 염소이온에 대한 저항성이 상대적으로 높게 나타나 거대 해양 구조물의 적용에 매우 유리한 시멘트로 판단되었다.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.30 no.3A
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• pp.229-239
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• 2010

For the purpose of improvement of the load carrying capacity and constructibility of the conventional steel-concrete composite girder through a effective appliance of the construction materials and optimization of the girder section, a new type section of composite girder and RC shear connection were proposed. In this study shear strength of the RC shear connection is estimated, and the characteristics of shear load-slip behaviour is analyzed. Push-out tests on shear specimens and FEM analysis with various design parameters are carried out, and results are analyzed. The results of test and FEM analysis showed that shear strength of RC shear connection is underestimated by the design provisions of the current design code. By regression analysis a empirical equation for the estimation of shear strength of RC shear connection is proposed.

• Journal of the Korean Magnetics Society
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• v.26 no.4
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• pp.133-136
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• 2016

In this study, we have constructed a measuring system to investigate tensile stress of tendons, which is employed in bridges, by means of the magnetic non-destructive testing (NDT) method. For the twisted 7-strands tendon, we have used Wiedemann effect. An ac current was applied to the tendon and voltage induced from Search Coil on Tendon (SCT) under applying tensile stress was measured. The measuring system consists of tensile stress applying apparatus up to 2 GPa, and ac current supply to apply current to the tendon directly to magnetize the tendon. We have invested two kinds of tendon which were produced by different companies for testing with constructed measuring system. Voltage induced from SCT was decreased up to 1.5 GPa linearly and two kinds of tendon which were produced by different companies shows similar trends. Thus, Wiedemann effect was also applicable to measure tensile stress of tendon by means of magnetic NDT.

• Korean Journal of Food Science and Technology
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• v.32 no.1
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• pp.9-16
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• 2000

Aroma of various extracts of Agastache rugosa O. Kuntze was analyzed by electronic nose with 32 conducting polymer sensor arrays. The 57 extracts were prepared by extraction solvents (hot water, ethanol and NaCl solution), extraction temperatures $(100,\;80\;and\;60^{\circ}C)$, solvent mixture ratios of solvent (10 times 35 times) and parts of Agastache rugosa O. Kuntze(flower, leaf and stem). Aroma pattern of Agastache rugosa O. Kuntze extracts showed big difference in normalized pattern and odor intensity with extraction temperatures and parts, but showed no difference with extraction solvents. Especially in the case of ethanol extracts, because odor of ethanol itself was very strong, difference in aroma of extracts with extraction temperatures and parts did not show through the electronic nose. The organoleptic characteristics such as mint odor, grassy odor, mint taste, medicinal herb taste and sweetness for Agastache rugosa O. Kuntze extracts were determined by the profile test and the result of sensory evaluation by quantitative descriptive analysis was explained to QDA diagram. In correlation with the result of aroma analysis by electronic nose and the sensory evaluation, difference in aroma pattern among the extracts concretely brought to light definite characteristics such as mint odor and mint taste.

• Horticultural Science & Technology
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• v.28 no.4
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• pp.656-663
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• 2010

In order to improve the consumer acceptance of fragrant yellow hybrids of $Phalaenopsis$ ($Phal.$), crosses between yellow hybrid varieties were made and the obtained hybrids were investigated for horticultural characteristics as well as difference in fragrance patterns. Cross combination of $Phal.$ Brother lawrence and $Phal.$ Brother saragold yielded good seedling population of 500 plants. Segregation was noticed in color density, spot and stripe patterns on yellow color base of petal and also in fragrance. Six lines with multi-branch on flower stalk and strong fragrance flower were finally selected. Volatile fragrance components were compared among $Phal.$ Brother lawrence, $Phal.$ Brother saragold and their hybrids by GC/SAW electronic nose. In the derivative pattern of chromatogram and polar derivative pattern of fragrance, similar dominant peaks appeared on retention time 7-9 s and some hybrid lines had two strong peaks on retention time 20-25 s, respectively. Also in polar frequency pattern of fragrance obtained by $VaporPrint^{TM}$ image analysis among parent flowers and hybrids, an identical strong peak near 8 s of retention time was shown. This single fragrance component is considered a key element of fragrance in $Phal.$ Brother lawrence, $Phal.$ Brother saragold and their hybrids. This peak could be used as a marker for the breeding of fragrance in $Phalaenopsis$.

• Journal of the Korea institute for structural maintenance and inspection
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• v.23 no.1
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• pp.147-153
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• 2019

The prestressing steel wire, which is applied a tension to reinforce the structure, is applied flexure simultaneously by the duct and the deviator. In order to evaluate the deflected tensile performance of the prestressing steel wire subjected to both tensile and flexural stresses, the numerical analysis for 600 cases with variables of wire diameters, mandrel diameters, and friction coefficient between mandrel and steel wire was performed. As the result of analysis, the larger the diameter of the steel wire was, the lower the deflected tensile performance was, and the effect decreased with the increase of the wire elongation. The effect of mandrel diameter and friction coefficient between mandrel and wire on the deflected tensile performance of the wire was very small. But the deflected tensile performance and the friction coefficient between mandrel and strand showed a relatively high correlation. Therefore, it is necessary to make enough large elongation to secure the deflected tensile performance. If there is a restriction on the elongation, it is necessary to reduce the diameter of the steel wire to an appropriate value, and to increase the friction between steel wires by adjusting the surface condition of the steel wire.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.18 no.3
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• pp.235-242
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• 1985

The mechanics of the walking shrimps is useful to clarify the fishing mechanisms in relation to the fishing gears. The gaiting behaviour concerning step positions and step timings on the flat board and the nettings, 16, 23 and 37mm in mesh size were experimented in the aquarium using video camera from June to October, 1984. It was found that the irregular movements of walking legs in step positions and step patterns were appeared on the nettings more than the flat surface due to the absence of mechanical contact with the substrates. The mean stride length and coefficient of variation of the periods in the walking shrimps on the flat board were significantly different from those values on the nettings, However, the velocity, the period and the ratio of forestroke to backstroke were unsteadily changed with the carapace length, and showed little difference under the four conditions. The mean phase difference on the flat board was greater than those values on the nettings which were decreased, while standard deviation on the flat board was smaller than those values on the nettings which were increased with increasing in mesh size.