• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.22 no.4
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• pp.107-113
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• 2008

We investigated the electro-optical characteristics of an ICP(Inductively Coupled Plasma) light source depending on driving temperature, and length of discharge tube. An electro-optical stability of a sample at operating was measured to see a steady state of a sample. In this results, we can see that a stability of power loss and luminous flux of a sample at operating of upper 70[min] was 1.45[%1 and 0.36[%]. We measured the optical characteristics of a sample in a thermal chamber operated at a specific temperature divided into 5 steps. While luminance increased with temperature increasing, the decrement of luminance a eared at u or $46.7[^{\circ}C]$. According to Parchen's and Boyle-Charles' law, we can speculate that a pressure was increased and a higher voltage was needed but a ballaster having a rating power can't support a higher voltage corresponding to a pressure change, 0.02[Torr] at $46.7[^{\circ}C]$. Moreover, we measured an a lied power and current of samples depending to a various length of a discharge tube.

• Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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• 2003.04a
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• pp.137.2-138
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• 2003

농산물의 효율적인 가공.저장은 농산물의 안정된 공급과 물가안정에 크게 기여하며, 부가가치 향상과 식품관련산업의 국제경쟁력 강화에도 필수적인 요건이라 할 수 있다. 호박은 전국 각지의 유휴지에서 별다른 시비나 농약의 사용없이 재배가능한 농산물로 vitamin C 및 vitamin A의 전구체인 carotene과 무기질, 식이섬유, 전분, 자당, 포도당 등이 풍부하다. 호박은 이뇨작용과 산후부종에 효과가 인정되어 널리 이용되고 있으며, 당뇨병, 야맹증, 각막건조증 등에도 효과가 있다. 국민의 생활수준이 향상되고 사회구조가 변화함에 따라 식품소비의 양상도 크게 변화하여 편의식과 건강 지향적인 가공식품의 수요가 급격히 증가하고 있으며, 이에 부응하여 건강식품에 관한 다각적인 연구가 많이 행해지고 있으나 미비한 실정이다. 호박은 특히 수분함량이 많고 조직의 연화현상 등으로 저장성이 낮아서 경제성이 떨어지므로 호박을 이용한 다양한 가공제품의 개발이 요구된다. 호박의 이용성을 검토하고, 나아가 호박의 부가가치 향상 및 경쟁력을 가진 지역특산물화를 위하여 기능성을 갖춘 건강음료개발을 시도하였으며, 이러한 음료의 유통중 품질변화를 모니터링하였다. 호박음료의 유통중 품질변화는 저장온도(20, 30, 40, 50, 6$0^{\circ}C$) 및 저장기간(0, 2, 4, 6, 8 week)에 따른 중심합성실험계획으로 실험을 행하여, 저장에 따른 당, 산, pH, 갈색도 및 관능적 특성에 대하여 반응표면분석을 하였다. 당도, 산도, pH 및 갈색도의 경우 저장시간에 영향을 많이 받는 것으로 나타났으며, 관능적 특성 중 전반적인 기호도에 있어서는 저장온도 및 저장시간에 영향을 많이 받는 것으로 나타났다. 당도, 산도, pH의 경우 저장온도 및 저장기간에 따라 큰 차이를 보이지 않았다. 갈색도의 경우 저장온도 51.1$0^{\circ}C$ 및 저장기간 7.33 week일 때 최대의 갈색도로 나타났다. 전반적인 기호도 있어서는 저장온도 32.52$^{\circ}C$ 및 저장기간 0.30 week일 때 우수한 것으로 나타났다.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.14 no.6
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• pp.1385-1394
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• 1994

A three-dimensional numerical model of surface buoyant jets with variable density was established. The model uses fully nonlinear, time-dependent, three-dimensional, ${\sigma}$-transformed equations of motion and equation of heat transport. A semi-implicit numerical scheme in time has been adopted for computational efficiency. The model was applied for thermal jets discharging into a stagnant water and the simulated results were compared with a hydraulic experimental data set showing good agreement. Comparative studies of exchange coefficients and stability functions indicated that spatial variation of exchange coefficients should be considered and the existing stability functions should be modified to simulate surface buoyant jets accurately.

• Korean Journal of Food Science and Technology
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• v.17 no.4
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• pp.265-270
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• 1985

The saponin yield and its compositional changes of red ginseng extract (RG-EXT) was investigated during extraction at various temperature for 5 times of 8 hours. The higher temperature resulted an increase in solids yield while the total saponin recovered was decreased, particularly at $100^{\circ}C$. A relatively lower thermal stability was found for protopanaxadiol saponin, one of the saponin fractions, than protopanaxatriol saponin. The compositional ratio of saponin at ginsenoside level was little affected by extraction time. The yields data showed that more than 94% of total saponin was recovered by 3$\sim$4 times of 8 hours extraction. Extraction at $80^{\circ}C$ for 4 times of 8 hours were suggested for preparation of RG-EXT from the result of this work.

• The Korean Journal of Nuclear Medicine Technology
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• v.13 no.1
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• pp.116-119
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• 2009

Background: Preanalytical factors can affect reliability of hormone assay results. Adrenocorticotropic hormone (ACTH) in blood is considered highly unstable because of proteolytic degradation, so storage of blood samples on ice until analysis is recommended. In clinical practice, however, this procedure may present logistical problems because most samples for ACTH measurement must be shipped from the place of sample collection to the laboratory. Therefore, we studied the impact of time and temperature before plasma separation and analysis on the results of ACTH assays. Methods: A total number of 22 patients were enrolled in this study. We obtained 2 blood samples. ACTH concentrations were 35~126 pg/mL. ACTH concentrations were measured by immunoradiometric assay (IRMA) using commercial kits (CIS Biointernational, Gif-sur-Yvette, France). Results: ACTH levels showed a significant difference between the samples of $22^{\circ}C$ EDTA and $4^{\circ}C$ EDTA. Measured ACTH concentrations significantly decreased with time before freezing at $-20^{\circ}C$. ACTH levels showed no significant difference between the groups of after storage for 24 hr without centrifugation at $22^{\circ}C$ and $4^{\circ}C$. Conclusion: We recommend that blood samples be obtained on pre-chilled EDTA collection tubes. The shortest possible time between sample collection and processing is always the best laboratory practice.

• Proceedings of the Korean Institute of Industrial Safety Conference
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• 1998.11a
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• pp.303-308
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• 1998

암반을 대상으로 하는 건설공사는 많은 시간과 비용, 설계, 시공, 안전상에 많은 문제점을 일으키고 있다. 이러한 암반들은 흡수, 풍화 등에 기인하여 안정성이 약화되어 낙석, 산사태, 붕괴 등의 위험을 안고 있으며 이러한 현상은 우기, 해빙기에 두드러지게 나타나고 있다 비균질, 비등방성의 역학적 성질을 지닌 암석은 변형 거동을 완벽하게 예측하지는 못하고 있는 실정으로 이러한 거동은 암석의 종류와 구성 광물, 내부 불연속면의 상태, 응력 조건과 온도, 습도의 함수비등과 같은 다양한 요소에 의해 영향을 받으며, 이러한 경향은 퇴적암의 경우 두드러지게 나타나고 있다. (중략)

• Journal of the Microelectronics and Packaging Society
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• v.5 no.2
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• pp.27-36
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• 1998

통신시스템의 고발열 전자부품 냉각을 위해 3종류의 써모싸이폰을 각각의 용도에 따라 개 발하였으며 그 각각의 설계변수에 대한 냉각특성을 실험적으로 구하였다. TS-I에서는 증발부 내부 에 금속스크린 메쉬형심지를 삽입함으로써 시간에 따른 온도 변화를 작게 하여 냉각성능 안정성을 확보하였고, TS-II에서는 9W/cm2의 높은 냉각성능을 가진 루프형 써모사이폰을 개발하였으며 TS-III에서는 작동유체의 종류, 파이프개수 와이어 삽입여부등 써모사이폰의 주요 설계변수에 따 른 냉각특성을 구하였다.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.13 no.6
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• pp.284-289
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• 2003

The electric furnace, inside which the desired temperature is kept by the generated heat, is known to be a difficult system to control and model exactly because system parameters and response delayed time are varied as the temperature and positions are changed. In this study, the GPCEW (generalized predictive control with exponential weight), which always guarantees the stability of the closed loop system and can be effectively applied to the internally unstable system, was introduced to the ceramic drying electric furnace and was verified by showing its temperature tracking performance experimentally.

• Applied Biological Chemistry
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• v.35 no.5
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• pp.410-414
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• 1992

Endoinulase from Streptomyces sp. S56 was immobilized by adsorption on DEAE-cellulose in 0.01 M citrate-sodium phosphate buffer, pH 6.0 and the properties of immobilized and free enzymes were investigated. The immobilized enzyme preparation, having 40 inulase activity units per dried matrix, revealed the maximal activity at $pH\;4.5{\sim}5.5$ and $55{\sim}60^{\circ}C$ and were most stable at pH 6 and 45^{\circ}C$. The immobilization caused a drop in optimum pH and affinity toward inulin, a slight increase in optimum temperature, an important increase in thermal stability and maximum reaction velocity. The immobilized endoinulase hydrolyzed the tuber extract of jerusalem artichoke and inulin, mainly into fructose and inulobise, degrading 63 and 78% of the total sugar respectively, within 48 hrs in batch reactor.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.29 no.5A
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• pp.551-555
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• 2009

This study is performed to apply a standard to evaluate fire protection assessment for tunnel structures when a fire breaks out in the road tunnel. Recently, a number of road tunnels have been rapidly increased and fire risk also multiplyed according to extend tunnel length, due to natural features and environmentally-friendly road construction in Korea. But we have not yet been prescribed appropriate time-temperature curve for tunnel fire. Therefore, we presented fire design model and investigated time-temperature curve proposed by a foreign country considering traffic, a kinds of vehicles which are a basis of heat rate. At the end, Hydrocarbon modified curve applied as design fire model by using numerical analysis and presented design fire model and examined the effects of tunnel structures.