• Transactions of the Korean Society of Mechanical Engineers B
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• v.30 no.4 s.247
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• pp.320-327
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• 2006

The computations of chemically reacting laminar and turbulent flows are performed using the preconditioned Navier-Stokes solver coupled with turbulent transport and multi-species equations. A low-Reynolds number $k-\varepsilon$ turbulence model proposed by Chien is used. The presence of the turbulent kinetic energy tenn in the momentum equation can materially affect the overall stability of the fluids-turbulence system. Because of this coupling effect, a fully coupled formulation is desirable and this approach is taken in the present study. Choi and Merkle's preconditioning technique is used to overcome the convergence difficulties occurred at low speed flows. The numerical scheme used for the present study is based on the implicit upwind ADI algorithm and is validated through the comparisons of computational and experimental results for laminar methane-air diffusion flame and $ H_2/O_2$ reacting turbulent shear flow. Preconditioning formulation shows better convergence characteristics than that of non-preconditioned system by approximately five times as much.

• Transactions of the Korean Society of Mechanical Engineers
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• v.17 no.1
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• pp.190-199
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• 1993

In order to find the effect of flame interaction on NO production, dual laminar diffusion flames issuing from two rectangular nozzles were investigated theoretically. Chemical equilibrium model and Zeldovich mechanism were used in numerical model. The effect of four major parameters on NO production were inspected. These parameters are nozzle spacing, Raynolds number, aspect ratio of nozle cross section and velocity of secondary flow. It is found that interaction of flames enhances production of n. It is also found that multiflames with large spacing, small aspect ratio and strong secondary flow product less n.

• Journal of Sericultural and Entomological Science
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• v.35 no.1
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• pp.69-72
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• 1993

Effects of topical application with 1, 5 and 10 ${\mu}$g/ml testosterone on the precocooning and post cocooning traits of the polyvoltine. Pure Mysore breed of silkworm were studied. Each concentration was treated independently at 36th to III, IV and V instar larvae(Treatment-1), at 48th to IV and V instar larvae(Treatment-2_ and at 72th to V instar larvae(Treatment-3). The repeated application with each concentration of testosterone propionate in treatment, and 2 larvae or single application in treatment 3 variously affected the precocooning and post cocooning traits. Repeated applications of all doses of testosterone propionate(Treatment-1) and single application of 1 & 5 ${\mu}$g of the chemical(Treatment-3) increase the fecundity and decrease the percentage of cocooning and moth emergence.

• FLOWER RESEARCH JOURNAL
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• v.18 no.2
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• pp.147-150
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• 2010

A new cultivar potted miniature rose (Rosa hybrida) 'Tiny Ball' was selected out of cross combination 1999 and 2002 at Gumi Floricultural Experiment Station. Characteristics trials were conducted three times from 2003 to 2006. 'Tiny Ball' came from the combination that '990905' crossed to 'Manish'. New cultivar has pink and white flower color and the shape of flower is similar to tiny ball. The number of flower petals and flowers per pot are more than those of 'POULra022' as comparison cultivar. This cultivar has low plant height without treatment of plant retardant materials, so the high quality grade ratio of potted rose is higher than that of comparison cultivar.

• Korean Journal of Agricultural Science
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• v.41 no.4
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• pp.299-302
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• 2014

A freesia (Freesia hybrida Hort.) 'Shiny Bell' was developed for the cut flower in the National Institute of Horticultural Herbal Science in 2012. This hybrid was selected from a crossing between cn. 'Teresa' and 'Rossini', which is white semi-double flowering and red double flowering, respectively. in 2004. Morphological characteristics of the selected hybrid were investigated for 3 years from 2009 to 2011, and then it was named 'Shiny Bell'. 'Shiny Bell' had red color of RHS W155C, and double flower. The growth of the plant was vigorous and the average height was 109.3 cm. The average flower width was 5.8 mm, number of floret per stalk was 11.3, and stalk length was 8.5 cm. The average yield, 7.3 Branches per plant, was 3 stems per plant more than the control cultivar. The average days to first flowering of 'Shiny Bell', was 143.3 days, and it was approximately 7 days later than the control cultivar. The average yield of 'Shiny Bell' was 4.0 cormlets per plant.

• Transactions of the Korean Society of Mechanical Engineers
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• v.15 no.1
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• pp.355-365
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• 1991

New definition for the interaction of flames is introduced and interacting turbulent diffusion flames issuing from two rectangular nozzles are investigated on the basis of the definition. Theoretical study through numerical model is carried out and experiment for validation is conducted. The characteristics of interaction due to the variation of major parameters such as nozzle spacing, Reynolds number and nozzle aspect ratio are studied. Results show that strong interaction occurs for small nozzle spacing, small Reynolds number and large aspect ratio. In order of their magnitude, the intensity of interactions on the individual transport mechanism is momentum, heat and mass. It is also found that interaction makes flames longer, tilted and finally merged. Increase of velocities and temperature, decrease of oxygen concentration and depression of turbulence are occurred in the region between flames.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.36 no.4
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• pp.321-327
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• 2008

The shock tunnel as a hypersonic ground test facility was designed, constructed and its performance test was conducted to reproduce the high speed flow which the hypersonic propulsion system is encountered. The design points were understood and the conceptual design was completed using the quasi one dimensional operation analysis code. After that, the specific performance and compartment design were completed using CFD simulation as the part analysis. The facility was then constructed according to those design results and the performance test was conducted for various operation conditions. In this paper, we suggested the design method of hypersonic shock tunnel including the conceptual and performance design using theoretical analysis and the quasi 1D Multi-species computational fluid dynamics code.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2018.10a
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• pp.117-117
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• 2018

강황(Curcuma longa L.)은 생강과(Zingiberaceae)에 속하는 다년생 아열대 초본 식물로, 약 40여 종이 존재한다고 알려져 있으며, 특유한 맛과 향기가 있어 세계적으로 널리 이용되고 있다. 현재 국내에는 전남 진도를 중심으로 경남, 제주 등으로 재배지역이 확대되고 있으며, 생산량이 증가하는 것으로 나타나고 있다. 한편, 강황은 우리나라에서 한약재와 식품원료로 구분하여 사용되고 있으며, 한약재 강황은 대한 민국약전을 근거로 규격품 한약재로서 품질관리가 이루어지고 있다. 특히, 국내산 강황은 대한민국약전의 지표성분 함량(쿠르쿠민, 데메톡시쿠르쿠민 및 비스데메톡시 쿠르쿠민의 합 3.2 % 이상)의 기준 규격에 미달되어 대부분 식품원료로 사용되고 있는 실정이다. 따라서, 본 연구는 강황의 비닐하우스 재배를 통해 한약재 활용 가능성을 알아보기 위해 수행되었다. 본 시험은 한약진흥재단 한약자원개발본부 시험포에서 수행되었으며, 강황 종근은 진도 재배 농가를 통해 수집되었다. 2017년 4월 20일에 일반 노지와 비닐하우스에 각각 정식하였다. 수확은 정식 후 200일에 각 실험구의 강황을 채취하여 초장, 엽수, 경경, 경수, 생체중, 건물중 등 생육 특성을 조사하였으며, 쿠르쿠민 함량 분석은 식품의약품안전처 고시법에 따라 HPLC를 이용하여 동시 분석 하였다. 하우스 재배가 강황의 생육에 미치는 영향을 살펴본 결과, 초장은 하우스 재배가 노지 재배에 비해 약 65% 높게 나타났으며, 엽수, 경경, 경수는 약 15~68% 높게 나타났다. 쿠르쿠민 함량은 하우스 재배가 노지 재배에 비해 약 53% 높게 나타났지만, 대한민국약전의 기준 규격에는 미달되었다. 따라서 본 연구 결과는 강황을 비닐하우스에서 재배할 때 생산성과 지표성분을 각각 68%, 53% 증수시켰지만, 한약재로 활용할 수 있는 기준 규격에는 못 미치는 것으로 나타났다. 향후, 강황 해외 지역종 수집 및 재배를 통하여 한약재 품질규격에 적합한 국내산 강황 재배기술 개발을 위한 기초자료로 활용이 가능할 것으로 사료된다.

• Progress in Medical Physics
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• v.4 no.2
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• pp.59-67
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• 1993

In this paper, we present a result of our study on how to construct a HIMCS(hospital image management and communication system) based on Windows system. The proposed HIMCS is composed of image acquisition units, image archiving and processing units, display units, and all units are interfaced with LAN. We construct high speed image transmission system for distributed database and retrieval of various medical pictures in ward through image transmission system and realize integrated image diagnosis. Hospital image management and communication systems(HIMCS) have been proposed as a way to meet the challenge presented by the growing volume of medical imaging data. These systems are based on the concept of handing images in digital form, there by marking use of advances in computer-based technology. A HIMCS offers a wide spectrum of advantages over filmbased imaging. Digital acquisition of images eliminates the need for film processing and associated costs in both time and materials.

• Korean Journal of Agricultural Science
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• v.40 no.4
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• pp.305-309
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• 2013

A freesia (Freesia hybrida Hort.) 'Dancing Flame' was developed for the cut flower in the National Institute of Horticultural Herbal Science in 2007. This hybrid was selected from a crossing between a seedling 'Vulcano' and 'Sailor', which is scarlet double flowering and purple single flowering, respectively, and 'Figaro' which is bright red color and semi-double flowering, in 2000. Morphological characteristics of the selected hybrid were investigated for 3 years from 2005 to 2007, and then it was named 'Dancing Flame'. 'Dancing Flame' had red color (RHS R44B) and single flower with yellow center color (RHS Y9A). The growth of the plant was vigorous and the average height was 93.3 cm. The average flower width was 60 mm, number of floret per stalk was 14.3, and stalk was 13.2 cm length. The average yield, 7.8 cuttings per plant, was 2.5 stems per plant more than the control cultivar. The average days to first flowering of 'Dancing Flame', 133 days, was approximately 5 days earlier than the control cultivar. And its average yield, 7.1 cormlet per plant, was also 2.5times more than the control cultivar.