• 한국연소학회:학술대회논문집
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• 한국연소학회 2007년도 제34회 KOSCO SYMPOSIUM 논문집
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• pp.107-113
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• 2007

The burning characteristics of interacting droplets with internal circulation in a convective flow are numerically investigated at various particle arrangement and size difference. In this simulation some conditions are fixed, surround gas temperature is 1250K, pressure is 10 atm and drolet's initial temperature is 300K. The transient combustion of arranged droplets, the fixed droplet distances of 4 radii to 20 radii horizontally, is studied. And the range of size of droplet is 75${\mu}m$ to 100${\mu}m$. The results obtained from the present numerical analysis reveal that the transient flame configuration and retardation of droplet internal motion with the horizontal spacing substantially influence lifetime of interacting droplets. At a Reynolds number 10, lifetime of the three droplets with decreasing horizontal droplet spacing increases monotonically. But when droplet spacing decreases further to 4radii, Lifetime of interacting droplets are increase. So Lifetime of interacting droplets exhibits a strong dependence on the horizontal droplet spacing and size difference. It can be investigated well with these conditions to that of single burning droplet.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1997년도 추계학술대회 논문집 학회본부
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• pp.339-341
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• 1997

From this first studies, We have investigated the latch-up characteristics of various CMOS well structures possible with high energy ion implantation processes. In this study, we also investigated those of STI(Shallow Trench Isolation} structures with varing n+/p+ spacing and the depth of trench. STI structure is formed by T-SUPREM4 process simulator, and then latch-up simulations for each case were performed by MEDICI device simulator for latch-up immunity improvement. STI is very effective to preventing the degradation of latch-up characteristics as the n+/p+ spacing is reduced. These studies will allow us to evaluate each technology and suggest guidelines for the optimization of latch-up susceptibility.

• 한국약용작물학회지
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• 제5권1호
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• pp.67-71
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• 1997

시호(柴胡) 성력화(省力化) 재배기술(栽培技術) 개발(開發)의 일환(一環)으로 기계파종시(機械播種時) 재식밀도(栽植密度) 차이(差異)가 생육과6 수량에 미치는 영향을 검토(檢討)코자 시험(試驗)한 결과(結果)를 요약(要約)하면 다음과 같다. 1. 인력파종기(人力播種機)를 이용(利用)한 파종(播種) 소요시간(所票時間)은 손파종(播種)에 비하여 조간(條間) 20 및 30cm 처리(處理) 모두 96%의 파종노력을 절감(節減)할 수 있었다. 2. 재식밀도(栽植密度)에 따른 입모수(立毛數)는 조간(條間) 및 주간(株間)이 좁아질수록 많아졌으며, 경장(莖長) 및 마디 수는 차이가 없었다. 3. 주간거리(株間距離)가 좁아질수록 경태(莖太), 분기수(分枝數), 지상부종(地上部重), 규근경(圭根莖), 생체중(生體重) 및 건근중(乾根重)등이 감소(減少)되는 경향(傾向)이었다. 4. 근수량(根收量)은 조간(條間) 20cm 처리(處理)가 30cm보다 증가(增加)되었으며, 주간거리(株間距離)에 따라서는 조간(條間) 20 및 30cm 처리(處理) 모두 밀식(密植)일수록 증가(增加)되어 적정(適定) 재식밀도(栽植密度)는 조간(條間) 20cm에 조파(條播) 또는 주간(株間) 5cm로 나타났다. 5. 재식밀도(栽植密度)를 다르게 할 경우 입모수(立毛數)와 근수량(根收量)과는 정상관(正相關)을 보여 유의성(有意性)이 인정(認定) 되었다.

• 한국광학회지
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• 제14권4호
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• pp.365-368
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• 2003

본 논문에서는 장주기 광섬유격자쌍을 이용하여 광섬유 Mach-Zehnder 간섭계(MZI)를 기계적인 방법으로 구현해 보았다. 제작한 간섭계의 장주기 광섬유격자쌍의 투과스펙트럼과 fringe spacing의 이론치과 실험치를 비교, 분석해 보았다. 그 결과, fringe spacing의 값은 이론치와 실험치가 비교적 잘 일치하는 것을 알았다.

• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 2000년도 춘계 학술대회논문집
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• pp.99-106
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• 2000

A method of two and three dimensional orthogonal grid generation with control of spacing by using the covariant Laplace equation is Presented. An important feature of the methodology is its ability to control effectively the grid spacing especially near the boundaries still maintaining good orthogonality in whole field. The method is based on the concept of decomposition of the global transformation into consecutive transformation of an approximate conformal mapping and au auxiliary orthogonal mapping to have linear and uncoupled equations. Control of cell spacing is based on the concept of reference arc length, and orthogonal correction is performed in the auxiliary domain. It is concluded that the methodology can successfully generate well controlled orthogonal grids around bodies of 2 and 3 dimensional configurations.

• 한국감성과학회:학술대회논문집
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• 한국감성과학회 2000년도 춘계 학술대회 및 국제 감성공학 심포지움 논문집 Proceeding of the 2000 Spring Conference of KOSES and International Sensibility Ergonomics Symposium
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• pp.380-384
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• 2000

Effectiveness of information conveyance in reading is affected by several factors such as line length, letter size, line spacing arrangement as well as typeface itself. This study examined relative importance of these factors by asking people to read the texts that was constituted with non-square form letter and rank the preference of texts through conjoint analysis. In the case of reading time, justification was the most important factor, followed by leading, line spacing, letter width, line length, font size, font type in their order of importance. And in the case of preference decision, letter width was the most important factor, followed by font size, justification, line spacing, leading, line length, font type. The result will be useful in understanding how to consider human preference in the hangul typography.

• 산업기술연구
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• 제24권A호
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• pp.157-164
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• 2004

Air voids in hardened concrete have an important influence on concrete durability such as resistance of freezing and thawing, permeability and surface scaling resistance. Linear traverse method and point count method in ASTM standard method have been widely used to estimate the air void system in hardened concrete. However, these methods are not used at present time, because they are is exhausted much time and effort. In previous study, air voids system of concrete was estimated by spacing factor. The purpose of this study organizes image analysis method by analyzing air contents, air voids distributions by diameters, air voids system as well as spacing factors after hardened concrete. The experimental variables institute of depth of specimen(top, middle, bottom), air contents(AE contents 0, 0.01, 0.03%).

• Asian-Australasian Journal of Animal Sciences
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• 제16권4호
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• pp.473-480
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• 2003

In order to control the genetic background noise in QTL mapping, cofactor markers were incorporated in single marker analysis (SMACO) and interval mapping (CIM). A simulation was performed to see how effective the cofactors were by the number of QTL, the number and the type of markers, and the marker spacing. The results of QTL mapping for the simulated data showed that the use of cofactors was slightly effective when detecting a single QTL. On the other hand, a considerable improvement was observed when dealing with more than one QTL. Genetic background noise was efficiently absorbed with linked markers rather than unlinked markers. Furthermore, the efficiency was different in QTL mapping depending on the type of linked markers. Well-chosen markers in both SMACO and CIM made the range of linkage position for a significant QTL narrow and the estimates of QTL effects accurate. Generally, 3 to 5 cofactors offered accurate results. Over-fitting was a problem with many regressor variables when the heritability was small. Various marker spacing from 4 to 20 cM did not change greatly the detection of multiple QTLs, but they were less efficient when the marker spacing exceeded 30 cM. Likelihood ratio increased with a large heritability, and the threshold heritability for QTL detection was between 0.30 and 0.05.

• 한국주조공학회지
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• 제27권2호
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• pp.77-82
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• 2007

The effects of thermal gradient and solidification rate on the dendrite arm spacing and carbide morphology were investigated in directionally solidified Ni-base superalloy, CM 247LC. Thermal gradient was controlled by changing the position of the cold chamber and the furnace set temperature. The interface morphology changed from the planar to dendritic as increasing solidification rate. It was found that the dendrite spacing decreased as increasing the thermal gradient as well as the solidification rate. Also, as increasing solidification rate, carbide morphology changed from blocky shape to script and spotty shapes.

• 터널과지하공간
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• 제14권6호
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• pp.429-439
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• 2004

국내 원전에서 발생되는 36,000톤의 사용후핵연료를 처분하기 위해서는 약 $4km^2$의 지하 처분장이 필요하다. 본 연구에서는 굴착량과 처분장 면적을 최소화하기 위한 지하 심부 처분장 배치의 최적화를 실시하였다. 열 해석 결과를 토대로 처분 터널과 처분공 간격이 처분장 배치에 미치는 영향을 고려한 결과, 처분장 면적과 굴착량은 처분 터널의 길이가 길어짐에 따라 감소하였다. 주어진 열적 기준을 만족하면서 처분장 면적을 줄이기 위해서는 처분 터널의 간격을 줄이고 처분공 간격을 늘리는 것이 유리하였으며, 반면에 굴착량을 최소화하는 경우 처분공 간격을 줄이고 처분 터널 간격을 늘려주는 것이 효과적인 것으로 나타났다.