• Proceedings of the Korea Society for Energy Engineering kosee Conference
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• 1995.11a
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• pp.56-61
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• 1995

균일한 속도를 갖는 주유동장에 연료를 분사하였을때 분사된 연료가 주유동장의 공기와 혼합되는 정도를 정량적으로 설명하기 위하여 실험과 수치 계산을 실시하였다. 본 연구에서는 혼합 진전 정도를 나타내기 위하여 혼합진전변수(mixing progress variable)를 도입하여 유동조건에 따라 혼합 정도를 정량적으로 비교하였다. 주유동 속도가 일정할때 분사 속도를 증가시키면 연료가 주유동장의 공기와 혼합이 촉진됨을 알 수 있었다.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2005.11a
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• pp.437-444
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• 2005

Experiments were carried out in an atmospheric pressure, lab-scale gas turbine combustor to see the effect of partial premixing on unstable flame structure and Nox emission characteristics. The swirl angle is 45 deg., fuel-air mixing degrees were varied 0, 50 and 100% respectively at equivalence ratio ranging from 0.53 to 0.79. The evolution of phased-locked OH chemiluminescence images were acquired with an ICCD. NOx emission characteristics were also investigated at each experimental condition. The effect of the fuel-air mixing degree on the flame structure was obtained from phase-locked $OH^*$ images. And it was obtained from local heat release characteristics that the information about the region which the combustion instability was amplified or damped. It also could be confirmed that $\sigma$ has greatly influence on NOx emission characteristics at lean regimes. It would be expected that it could provide invaluable data for understanding the mechanism of combustion instability.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.19 no.1
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• pp.85-107
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• 1993

The cosmetic fine powders were mixed with variation of mixing time(5) in the mixers (ribbon mixer, powder mixer, micropulverizer and fine impact mill). The powders were nixed with small amount of ferric oxide. as tracer. The mixed powders ere measured the particle size distribution, specific surface area and surface color with mixing time (s). The color variation, particle size distribution and specific surface area of the mixed powder exist a relationship with mining time(s) that can be expressed as mathematical equations to show the degree of the mixing of the powder mixture. The linear velocity of the impellar tip is the main factor contributing to he mixing efficiency of the mixers un this study. According to the linear velocity, he mixers used are devieded as convection mixing (ribbon mixer), sclera mixing powder mixer) and diffusion mixing (micropulverizer/fine impact mill).

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2007.11a
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• pp.110-113
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• 2007

LES code was developed and verified to investigate the turbulence evolution in the gas generator equipped with turbulence ring. We compared mixing enhancement of various turbulence rings having different shape and size. To qualify the mixedness, we used two perturbation values of energy and enstrophy.

• Proceedings of the Korean Information Science Society Conference
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• 2000.10a
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• pp.539-541
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• 2000

윈도우 방법과 인수분해 방법을 혼합 적용하면 멱승 연산에 사용되는 곱셈 연산의 횟수를 줄임으로써 멱승 연산을 빠르게 수행할 수 있다. 지수가 512비트일 때 윈도우의 크가 5인 윈도우 방법은 607번 정도의 곱셈 연산을 필요로 하는데 반해 윈도우와 인수분해 방법을 혼합한 방법은 599번 정도의 곱셈 연산을 필요로 한다. 이는 현실적으로 가능한 멱승 연산 중에서 가장 적은 수의 곱셈 연산을 요구하는 방법이다.

• Korean journal of food and cookery science
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• v.3 no.2
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• pp.59-67
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• 1987

In order to make use of Job's tears widely, Job's tears starch was analyzed and determinded the contents of amylose, amylographical and other physicochemical properties. And also the yeast breads and rice cakes were made from flour and rice flours with various mixing ratios of Job's tears flour and then they were tested for suitability to preparation of bread and rice cake. 1. The starch contents of Job's tears showed 12~20%. Which was about one third of rice or waxyrice starch. But amounts of crude proteins, fats, and total ashes in Job's tears were higher than rice or waxyrice. Job' tears starch was composed of amylopectins only, and was similar to that of waxyrice starch. 2. Depends upon the Amylogram of each starch, initial gelatinization temperature of Job's tears starch was the highest among three starches of rice, waxyrice, and Job's tears. Maximum viscosity of Job's tears starch was 860BU, then it was about two times of rice starch viscosity. 3. By the sensory evaluation results, the taste of bread prepared with mixing of 10% Job's tears flour was better than flour bread and the volume and grains of the bread made from mixing of 10%, 20% Job's tears flour were similar to that of flour bread, but the taste, volume and grains of bread made from 30% mixed flour were undesirable. The rice cake Prepared from mixed flour with 25% Job's tears flour has shown to be desirable.

• Journal of the korean Society of Automotive Engineers
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• v.9 no.5
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• pp.19-24
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• 1987

본 문에서는 선회의 정도를 나타내는 선회도가 크고 작은 대표적인 두가지 경우에 대하여 시간평균 구조와 난류혼합 특성을 나타내는 시간변동치의 상관관계를 실험적으로 구한 예를 제시함으로써 선회운동에 의한 난류혼합특성을 설명하고자 한다.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.20 no.2
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• pp.127-132
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• 1984

Performance tests of small diesel engine were carried out, using the blend fuel oil as the substitute fuel oil and the following results were obtained. (1) The character at the blend oil as substitute fuel for small diesel engine was examined. (2) In the case of operating small diesel engine with blend oil, the exhaust gas volume increases at 8% in comparison with diesel oil. (3) In the case of operating small diesel engine with blend oil, the fuel consumption Increases at 3% in comparison with diesel oil. (4) In the brake thermal efficiency, blend oil is similar to diesel oil.

• Proceedings of the Korean Nuclear Society Conference
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• 1998.05a
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• pp.577-583
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• 1998

직접 접촉에 의한 응축 열전달은 혼합증기의 레이놀즈수, 비응축 가스(공기)의 질량비, 액막의 레이놀즈수, 그리고 액막의 과냉 정도에 따라 영향을 받게 된다. 이러한 변수들의 영향을 고찰하기 위하여 본 연구에서는 수평면으로부터 87˚ 기울어진 수직 사각 덕트에서 직접 접촉 응축 열전달 실험을 수행하였다. 위의 각 실험 변수에 따른 평균 열전달 대수의 변화를 고찰하였으며, 실험결과로부터 혼합증기 레이놀즈수, 비웅축 가스의 질량비, 액막 레이놀즈수, 그리고 제이콥수를 변수로 하여 직접 접촉 응축 열전달에 대한 평균 누셀트수에 대한 실험 상관식을 도출하였다. 혼합증기의 직접 접측 웅축 열전달에 대한 평균 열전달 계수는 비응축 가스의 질량비가 증가할수록 현저히 증가함을 보였으며, 액막의 과법 정도가 증가할수록 평균 열전달 계수는 감소하였다. 그리고 혼합증기의 레이놀즈수가 30,000 이상의 템위에서는 액막 레이놀즈수의 변화에 따라 평균 열전달 계수의 변화가 거의 없었다.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2010.11a
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• pp.614-615
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• 2010

The propellants distribution of an oxidizer rich preburner was predicted by a simplified physical approach. The Mixing head is composed of honeycomb array of 7 fuel injectors and 24 oxidizer injectors. The OF ratio of the mixing head is 15. As results, the OF ratio of the central area is about 9 and the OF ratio of the wall area is about 30.