• Title/Summary/Keyword: KD

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Development of KD- Propeller Series using a New Blade Section (새로운 날개단면을 이용한 KD-프로펠러 씨리즈 개발)

  • J.T. Lee;M.C. Kim;J.W. Ahn;H.C. Kim
    • Journal of the Society of Naval Architects of Korea
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    • v.28 no.2
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    • pp.52-68
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    • 1991
  • A new propeller series is developed using the newly developed blade section(KH18 section) which behaves better cavitation characteristics and higher lift-drag ratio at wide range of angle-of-attack. The pitch and camber distributions are disigned in order to have the same radial and chordwise loading distribution with the selected circumferentially averaged wake input. Since the geometries of the series propeller, such as chord length, thickness, skew and rate distribations, are selected by regression of the recent full scale propeller geometric data, the performance prediction of a propeller at preliminary design stage can be mure realistic. Number of blades of the series propellers is 4 and the expanded blade area ratios are 0.3, 0.45, 0.6 and 0.75. Mean pitch ratios are selected as 0.5, 0.65, 0.8, 0.75 and 1.1 for each expanded area ratio. The new propeller series is composed of 20 propellers and is named as KD(KRISO-DAEWOO) propeller series. Propeller open water tests are performed at the experimental towing tank, and the cavitation observation tests and fluctuating pressure measurements are carried out at the cavitation tunnel of KRISO. $B_{P}-\delta$ curves, which can be used to select the optimum propeller diameter at the preliminary design stage, are derived from a regression analysis of the propeller often water test results. The KD-cavitation chart is derived from the cavitation observation test results by choosing the local maximum lift coefficient and the local cavitation number as parameters. The caviy extent of a propeller can be predicted more accurately by using the KD-cavitation chart at a preliminary design stage, since it is derived from the results of the cavitation observation tests in the selected ship's wake, whereas the existing cavitation charts, such as the Burrill's cavitation chart, are derived from the test results in uniform flow.

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Application of the Distribution Law to Soil-Pesticide Systems (토양농약계(土壤農藥系)에 대(對)한 분배법칙(分配法則)의 적용(適用))

  • Shin, Young Oh;Baker, John H.
    • Korean Journal of Soil Science and Fertilizer
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    • v.7 no.1
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    • pp.1-4
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    • 1974
  • The application of the Distribution Law to soil-pesticide systems yielded the following empirical implications : 1) The amount of the pesticide adsorbed by a soil is negatively proportional to the soil water content. 2) At a given soil water content the amount adsorbed is proportional to the Kd of the soil. 3) The effect of soil water content on the amount of the pesticide adsorbed diminishes with increasing magnitude of the Kd.

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High Fidelity Calculation of Thermal Load in a Satellite Orbit (고정확도의 인공위성 궤도 열하중 계산 기법)

  • Kim, Min-Ki
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.45 no.10
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    • pp.898-906
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    • 2017
  • This paper discusses the efficient high fidelity calculation of external thermal loads of a spacecraft on its orbit. Thermal loads to a spacecraft consist of three major components, direct solar radiation, earth reflection of solar rays, and earth irradiation. With the assumption that both earth reflection and earth emission are diffuse, thermal loads from earth surface divided into pieces of segments to satellite surfaces are individually calculated and summed over. By using analytical integration of both reflected and emitted heat load by earth, high rate of numerical convergence is achieved and the results are even exactly calculated in special cases. Moreover, KD tree ray tracing is employed in the calculation of thermal load to determine whether the radiated ray is obstructed or not by satellite structure.

Modeling Knot Properties for Mongolian Pine in Northeast China

  • Jia, Weiwei;Li, Fengri;Jiang, Lichun
    • Journal of Korean Society of Forest Science
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    • v.97 no.5
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    • pp.485-491
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    • 2008
  • This study was performed in 14 unthinned Mongolian pine (Pinus sylvestris L. var. mongolica Litvin) plantations in northeast China. Data were collected on 70 sample trees of different canopy position with diameter at breast height (DBH) ranging from 6.9 cm to 34.5 cm. Diameter and length of knots per whorl below the living crown were studied by different vertical levels divided by relative knot height (RHK) in this paper. Models taking DBH and height to the crown base (HCB) as independent variables were developed to predict knot diameter (KD) in a sample whorl. According to the vertical distribution tendency and range of sound knot length (KLsound), KLsound was modeled as multiple linear function of DBH, KD and relative knot height (RHK). The loose knot length (KLloose) was described as a function of DBH, KD and height above the ground for knots (HK) in a mixed log-linear model. Results from this study can provide abundant knot information so as to describe the knot size and vertical distribution tendency of Mongolian pine plantation.

비스판 변이주에 의한 활성아포 생산성 증가

  • Jeon, Gyeong-Dong;Lee, Gwang-Ho;Kim, Won-Seok;Baek, Hyeon-Dong
    • 한국생물공학회:학술대회논문집
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    • 2000.04a
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    • pp.275-278
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    • 2000
  • Bacillus polyfermenticus SCD which is commonly called as 'Bispan strain' has been appropriately used for the treatment of long-term intestinal disorders, since the live strains in the form of active endospores can successfully reach the target intestine. The goal of this study were to get the novel bispan mutant strain and to get higher spore number of bispan mutant in submerged fermentation. Bispan mutant KD21 was obtained using NTG mutagenesis of bispan strain, and bispan mutant was cultivated in 5 L jar fermenter. In this study, productivity and sporulation rate of the bispan mutant KD2l showed approximately 77% increase when compared with bispan strain.

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Molecular Cloning of Serratia rnarcescens Metalloprotease Gene into Escherichia coli (Serratia marcescens Metalloprotease 유전자의 대장균에로의 클로닝)

  • 김기석;이창원;이상열;이병룡;신용철
    • Microbiology and Biotechnology Letters
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    • v.20 no.3
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    • pp.280-288
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    • 1992
  • Molecular cloning of metalloprotease gene from Serratia marcescens ATCC 21074 into Escherichia coli JM109 was carried out. Chromosomal DNA of S. marcescens was completely digested with Hind111 and southern hybridization with a synthetic oligonucleotide probe revealed that a 50 KD metalloprotease gene was contained in 4.0 Kb chromosomal DNA fragment, 4.0 Kb chromosomal DNA fragments eluted from agarose gel were ligated with pUC19 and transformed into E. coli JM109. Nine positive clones were obtained from about $1\times 10^3$ transformants by colony hybridization. Their recombinant plasmids, pSPl and pSP2 have same chromosomal DNA fragments in pUC19 in opposite-orientations. When cloned metalloprotease gene was expressed in E. coli, about 52 KD precursor protein of metalloprotease was detected by western blot analysis from E. coli harboring a recombinant plasmid pSP2. Plasmid pSP2 showed no protease activities in E. coli but overproduced the active metalloprotease in S. rnarcescens ATCC 27117.

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Surgical Correction of Complete Vascular Ring Associated with Kommerell's Diverticulum (Kommerell 게실과 동반된 완전 혈관륜의 수술적 교정)

  • Kim, Hee-Jung;Jung, Sung-Ho;Kim, Kyung-Mo;Yun, Tae-Jin
    • Journal of Chest Surgery
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    • v.39 no.12 s.269
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    • pp.943-945
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    • 2006
  • An 11-month old girl with a feeding difficulty and recurrent aspiration pneumonia received surgical correction of complete vascular ring, which was formed by right aortic arch, aberrant left subclavian artery(LSCA) originating from Kommerell's diverticulum(KD) and ligamentum arteriosum. Through left posterolateral thoracotomy, the ligamentum arteriosum was divided to relieve the tracheo-esophageal bundle. KD was separated from the right descending aorta, and the left subclavian artery was severed from KD at its origin and trasfered to the side wall of left common carotid artery. Postoperative course was uneventful, and the patient has been followed up with a clinical improvement.

Lower fat and better quality diet therapy for children with pharmacoresistant epilepsy

  • Yoon, Jung-Rim;Kim, Heung Dong;Kang, Hoon-Chul
    • Clinical and Experimental Pediatrics
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    • v.56 no.8
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    • pp.327-331
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    • 2013
  • The ketogenic diet (KD) is an established, effective, nonpharmacologic treatment for children with pharmacoresistant epilepsy. Although the KD is the most well-established dietary therapy for epilepsy, it is too restrictive and is associated with serious complications; therefore, alternative lower-fat diets, including a modified Atkins diet and low-glycemic index diet, have been developed. Recent ongoing clinical evidence suggests that other dietary therapies have an efficacy almost comparable to that of the KD. In addition, a diet rich in polyunsaturated fatty acids appears to increase the efficacy of diet therapy and reduce the complications of a high-fat diet. Here, we review the systematic information about lower-fat diets and better-quality dietary therapies and the current clinical status of each of these dietary approaches.

Atypical Kawasaki Disease Presented with Toxic Shock Syndrome (독성 쇼크 증후군 증상을 나타낸 비전형적 가와사끼병 1례)

  • Lee, Kyoung Yeon;Park, Jun Eun;Park, Woo Sung
    • Clinical and Experimental Pediatrics
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    • v.45 no.8
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    • pp.1048-1051
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    • 2002
  • Toxic shock syndrome(TSS) is clinically similar to Kawasaki disease(KD) in that both of them are characterized by fever, desquamating rash and mucous membrane erythema. In contrast the main feature of TSS is hypotension, whereas the complication of KD is coronary vasculitis. We report an 8-year-old boy who fulfilled the crireria for TSS and KD. Initially he showed clinical features of TSS, so he was treated with intravenous antibiotics and supportive management. But the fever sustained, and the coronary aneurysm that is the main complication of Kawasaki disease was shown by echocardiogram on Day 14. He was treated with intravenous immunoglobulin twice and the fever subsided and general condition was improved.

A stydy on The Biological Control of Sciarid Fly(Lycoriella sp.) Using Bacillus thuringiensis (Bacillus thuringiensis를 이용한 버섯 파리(Lycoriella sp.)의 생물적 방제에 관한 연구)

  • Choi, Kwang-Ho;Park, Hyean-Cheal;Park, Hyun-Woo;Jin, Byung-Rae;Kang, Seok-Kwon;Sohn, Hung-Dae
    • Journal of Life Science
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    • v.6 no.4
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    • pp.293-298
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    • 1996
  • Thirteen subspecies of Bacillus thuringiensis including B. t. israelensis, B. t. morrisoni PG-14 and B.t. darmstadoemsos known to be toxic to dipteran insects were treated on the mushroom (Flammulina velutipes) compost to estimate the biological control effect of a sciarid fly, Lycoriella sp. According to the results, it was found that there were no significant effects of the tested strains of B, thuringiensis on the control of Lycoriella sp. For further confirmation, larval gut juice of Lycoriella sp. and trypsin were respectively treated into the parasporal crystal proteins of three subspecies of B. t. israelensis, B. t. morrisoni PG-14, and B. t. darmstadiensis. The proteins were separated by SDS-PAGE. According to the results, the major parasporal crystal proteins were respectively produced by B. t. morrisoni as the amount of 52 kd, B. y. israelensis as 37kd and B. t. darmstadiensis as 39kd, but the activity of these proteins could not be unfortunately confirmed in this study.

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