• 한국수자원학회논문집
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• 제47권11호
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• pp.1007-1015
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• 2014

본 연구에서는 실내실험을 통하여 국내 중 소하천에 가장 많이 설치되고 있는 개량형 공압식 가동보를 대상으로 다양한 유량 변화에 대한 흐름특성을 분석하고, 유량계수산정식을 도출하였다. 실험결과, 가동보 기립각도에 따라 월류유량계수 ($C_d$)의 값은 0.613~0.634로 산정되었으며, 상류 Froude number ($F_{r1}$), 상대위어길이(${\xi}$), 전수두비($H_1/W$), 상류수심과 위어마루를 월류하는 수심의 비($y_c/y_1$)는 상류의 영향을 받으며 하류 Froude number ($F_{r2}$), 하류수심과 위어마루를 월류하는 수심의 비($y_c/y_2$)는 하류의 영향을받아 변화하였다. 상 하류수위차와 하류수심의 비(${\Delta}y/y_2$)는 상 하류의 영향을 모두 받아 변화되는 특성을 보여주었다. 주요 영향변수를 고려하여 다중회귀분석에 의한 유량계수산정식을 도출한 결과, 개량형 공압식 가동보의 월류유량계수는 상류흐름 조건이 상류일 때, 가동보의 높이 즉, 기립각도에 따른 물리적 제원과 상류 접근흐름수두의 조건에 의하여 결정되는 것으로 나타났다.

• Journal of Plant Biotechnology
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• 제2권3호
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• pp.157-163
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• 2000

Optimization of chemicals in the large scale sea water medium and inoculum for biomass and natural colourants production in the marine cyanobacteria, Phomidium tenue BDU 46241 (phycoerythrin producer) and P.valderianum BDU 30501 (phycocyanin producer) was carried out by experiments in L8 orthogonal array. Mathematical analysis revealed the significance of these factors. The factor(s) that critically control the yield varied with the organism and the end-product further, the desirable level of these factors between the normal and a higher level tested was identified and improved media were evolved. In both cyanobacteria, higher level of $K_2$$HPO_4$, $NaNO_3$ and inoculum with normal level of ferric ammonium citrate was found to be desirable for biomass production and additionally, higher level of $MgSO_4$ for pigment production. The level of other factors varied with the organism and the end-product. Confirmation experiments showed that the clues obtained based on mathematical experimentation are valid. In P.tenue, the medium optimized for biomass production increased the yield of biomass by 495% and the medium optimized for phycoerythrin production increased the yield of biomass by 408% with 30% increase in phycoerythrin content of the biomass. Similarly in P.valderianum, the medium optimized for biomass production increased the yield of biomass by 224% and the medium optimized for phycocyanin production increased the yield of biomass by 143% with 44% increase in phycocyanin content of the biomass.

• 대한기계학회논문집A
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• 제38권5호
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• pp.489-495
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• 2014

마이크로 유전알고리즘은 적은 수의 개체 사용 및 무작위 개체 구성을 통한 돌연변이 기능 대체의 특징을 갖는 진화연산을 수행하여 일반적인 유전알고리즘이 갖는 각 세대당 많은 계산 량이 요구되는 단점을 극복하고자 하였다. 이러한 마이크로 알고리즘은 특히 설계변수가 3~5 개를 갖는 문제에 효율적이라는 것이 많은 연구자들에 의하여 알려졌다. 따라서 본 연구의 목적은 순차적 실험계획법과 마이크로 유전알고리즘을 이용한 최적화 알고리즘을 개발하는 것이며, 이를 수학예제와 구조물 문제에 적용하여 실용성을 확인하고자 한다. 순차적 실험계획법은 저자들의 선행연구에서 제안되었으며, 실험계획법과 반응표면법을 이용하는 근사최적화 기법에 의한 시행착오적인 반복과정을 최소화하고자 하는 방법으로써, 행렬실험과 평균분석을 반복 적용하는 개념이다.

• 한국도로학회논문집
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• 제18권3호
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• pp.59-65
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• 2016

PURPOSES : This paper aims to develop a road pavement de-icing system using carbon sheet to replace the older snow de-icing method. Carbon sheet is a light and high-strength metal. Hence, various bodies of research for its applications in many industries have progressed. METHODS : The experiment was conducted in a laboratory. The carbon sheet supplied voltage through a power supply system, and produced heat transfers to the concrete surface. Various factors, such as pavement material, carbon sheet width, penetration depth, and freezing-thawing resistance, were considered in the conducted experiments to confirm the heating transfer efficiency of the carbon sheet. RESULTS : The carbon sheet used was a conductor. Therefore, it produced heat if voltage was supplied. The exposed carbon sheet on the atmosphere did not affect the carbon sheet width when it provided constant voltage. However, the sheet showed different heating behaviors by width change when the carbon sheet penetrated into the concrete. Moreover, the freezing-thawing resistance was decreased by the carbon sheet with increasing width. CONCLUSIONS : The experiments confirmed the possibility of developing a road snow melting system using a carbon sheet. The antiicing system using the carbon sheet to replace the traditional anti-icing system has disadvantages of environmental pollution risk and electric leakage. The pavement also improved its toughness resistance. The utilization value will be very high in the future if carbon sheet heat loss can be minimized and durability is improved.

• 디자인학연구
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• 제18권2호
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• pp.201-210
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• 2005

본 연구에서는 복잡한 기능을 가진 A/V기기 리모컨의 사용성을 저해하는 요인은 무엇인가 파악하고, 이를 개선하기 위한 사용성 결정 인자를 설정하여 사용성 비교 실험을 수행하고, 개선안을 제시, 이 개선안이 기존의 안에 비하여 우월하다는 점을 증명하고자 한다. 리모컨의 사용성 저해 요인을 파악하기 위하여 40여종의 각종 A/V관련 제품의 리모컨을 조사 분석하였다. 이를 통하여 사용성에 영향을 미치는 인자를 추출해 내고, 차기 버전의 플레이앳티비$(Play@TV^{TM})$용 리모컨을 선정하는데 이 인자를 만족하는 3개의 안을 도출해냈다. 기존의 리모컨과 새롭게 제시하는 3개의 리모컨 안에 대하여 사용성 테스트를 수행하여, 정성적, 정량적 분석을 하였다. 분석 결과 개선안 B가, 동일한 과제를 수행하는데 기존 리모컨에 비하여 9.2% 시간이 덜 걸리는 것을 확인 할 수 있었다. 이와 같은 결과는 본 연구에서 제시하는 리모컨 사용성의 결정인자, 즉, 기능수용성, 촉각적 단서의 제공, 적절한 크기와 무게, 주요 키의 배치 방법, 관련 기능의 그룹핑 등이 제품의 사용성을 개선하는데 유효함을 보이는 것이라 하겠다.

• 수산해양기술연구
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• 제41권2호
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• pp.147-155
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• 2005

This study was conducted in order to improve the automatic fishing operation system for anchovy boat seine by comparison with the fishing gear geometry and efficiency using the labor saving nets and the combined type net with midwater trawl. Field experiments were carried out to observe the geometry of nets and improve the fishing operation system by catcher boats. The vertical net opening of fore wing net, square, fore bag net and after bag net of the combined type net were varied in the range of 9.9~12.9. 16.2~28.2, 6.8~12.1 and 9.5~15.2m respectively, when the towing speed was 1.0m/sec and the distance between boats were 100m, 200m, 300m. The vertical net opening of the combined type nets was gradually decreased as function of with increasing the distance between catcher boats. Labor saving net which was maintained the net opening and towing depth stable was more suitable for the automatic hauling operation system by improvement of bag net rather than the combined type nets which was impossible in swallow depth and near to anchovy school. 3 boats hauling operation system of the labor saving net was carried out by crane with power block in 2 catcher boats for improvement of hauling operation and pushing equipment of anchovy cooking system in the processing boat for maintain more anchovy in dry frame. From the results of field experiments, 3 boats hauling operation system with power block and improved cooking system was very 3 boats hauling operation system with power block and improved cooking system was very useful and more practical as hauling time 20~35min and No. of fishermen 12~13 in comparison with the traditional system such as hauling time 30~50 min and No. of fishmen 28~38.

• Asian-Australasian Journal of Animal Sciences
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• 제12권8호
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• pp.1200-1204
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• 1999

Two experiments were conducted to study the effect of urea treatment of rice and wheat straw on feed intake, dry matter (DM) digestibility and milk yield of lactation buffaloes in their late lactation under farmers' management conditions in the western hills of Nepal during 1995 and 1997. Dry matter intake (DMI) from urea treated rice and wheat straw was not improved significantly (p<0.05) nor the total DMI of the lactating buffaloes was improved significantly. However, feeding urea treated rice straw increased straw DMI by 14.2% and total DMI by 10.63% units over the untreated rice straw. Similarly, the increase in straw and total DMI were 20.18 and 17.40% units over the untreated wheat straw fed animals. Although there was no significant effect of urea treatment of both straw on DM digestibility, it was higher for treated than untreated straw at all locations. An overall increment of 18.1% units for rice straw and 13.3% units for wheat straw was observed. There was a significant effect (p<0.01) of feeding urea treated rice and wheat straw on the milk yield of lactating buffaloes during late lactation under farmers conditions. Post experiment milk yield was also significantly (p<0.05) higher for the animals fed treated straw in both the experiments. Buffalo milk yield was also significantly affected by breed (p<0.01), location (p<0.01) and parity (p<0.01) of the animals. General response of the farmers about the technology and their observed effect on animal performance was also very positive.

• 한국생활과학회지
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• 제19권4호
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• pp.699-707
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• 2010

Catechu is widely used as in natural dyeing as well as in various medicines and tannage. This study investigated the dyeing properties and functionality of Catechu through a series of dyeing experiments using cotton fabric. It was shown that the absorbance of Catechu solution has two peaks at 220nm and 280nm. Thus, it can be concluded that the color constituent of Catechu is a catechol tannin and color tone is YR. The dyeability of Catechu increases as the concentration of the dye is increased. Its variation was shown to be similar to the isothermal absorption curve of the Freundlich. As dyeing time was increases, the dyeability did not change significantly after the 30 minute mark was passed. At high temperatures the dyeability was shown to increase. As the dyeing temperature was increased the color of dyeing fabrics changes from Y and YR to R. Experiments with pre-mordanting method showed that various colors can be obtained using Catechu. Cotton is effective in using K, Cu, Fe mordants, and the dyeability was shown to be improved with low pH. Both washing fastness and light fastness were shown to be low. However, the fabric color gradually changed to red was due to mailard reaction of catechol tannin causing by repeated washing and sunlight. The ultraviolet-cut ability was improved for cotton fabric dyed with Catechu. Also, dyed fabric with Catechu showed very good antimicrobial abilities at 99.9%.

• 고려인삼학회:학술대회논문집
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• 고려인삼학회 1993년도 학술대회지
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• pp.40-48
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• 1993

Intravenous administration of saponin extracted from the root of Panax ginseng lowered the blood pressure dose-dependently (10-200 mg/kg, B.W) in anesthetized rats. Therefore, experiments were designed to study the hypothesis that the lowering of blood pressure is associated with the release of endothelium-derived relaxing factor and the accumulation of guanosine 3, 5-cyclic monophosphate (cGMP). Rings of thoracic aorta with and without endothelium were suspended for the measurement of isometric tension in organ chamber and the tissue content of cGMP was measured by radioimmunoassay. All experiments were performed in the presence of $indomethacin(10^{-5}M).$ Ginseng saponin $(10^{-5}-3{\times}10^{-6}g/ml)$ relaxed contractions induced by phenylephrine $10^{-6}M)$ in the aorta with endothelium but not in that without endothelium. Treatment of aortic rings with $N^G$ monomethyl-L-arginine (L-NMMA, $10^{-4}M$ for 30 min), a competitive inhibitor of nitric oxide synthase, and methylene blue $(MB,\;3{\times}10^{-7}M$ for 30 min). an inhibitor of soluble guanylate cyclase, diminished the relaxation induced by Ginseng saponin. Ginseng saponin $10^{-4}g/ml$ for 2 min) increased the accumulation of cGMP in rings with endothelium. L-NMMA and MB inhibited the accumulation of cGMP induced by Ginseng saponin. These data suggest that vascular relaxations induced by Ginseng saponin are mediated by release of endothelium-derived relaxing factor and the accumulation of cGMP. The effect of Ginseng saponin on endothelial function in hypercholesterolemic rabbits was examined. In hypercholesterolemic rabbits fed with $2\%$ cholesterol for 8 weeks, relaxation of aortic rings to acetylcholine was impaired. The impaired relaxations of aortic rings in hypercholesterolemic rabbits were improved by dietary supplementation of Ginseng saponin, probably because of an improved release of endothelium - derived relaxing factor.

• 대기
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• 제29권5호
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• pp.567-583
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• 2019

In this study, the high-resolution numerical simulations considering detailed anthropogenic heat, albedo, emission and roughness length are analyzed by using single layer Urban Canopy Model (UCM) in Weather Research Forecast (WRF). For this, improved urban parameter data for Seoul Metropolitan Area (SMA) was collected from global data. And then the parameters were applied to WRF-UCM model after it was processed into 2-dimensional topographical data. The 6 experiments were simulated by using the model with each parameter and verified against observation from Automated Weather Station (AWS) and flux tower for the temperature and sensible heat flux. The data for sensible heat flux of flux towers on Jungnang and Bucheon, the temperature of AWS on Jungnang, Gangnam, Bucheon and Neonggok were used as verification data. In the case of summer, the improvement of simulation by using detailed anthropogenic heat was higher than the other experiments in sensible flux simulation. The results of winter case show improved in all simulations using each advanced parameters in temperature and sensible heat flux simulation. Improvement of urban parameters in this study are possible to reflect the heat characteristics of urban area. Especially, detailed application of anthropogenic heat contributed to the enhancement of predicted value for sensible heat flux and temperature.