• 한국해양학회지
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• 제28권2호
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• pp.114-120
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• 1993

입도분포의 특징분석에 종래의 조직특성치 대신 수치해석적인 분해법의 적용을 시 도하였다. 그 결과 이 방법이 제주해협의 대륙붕 표층퇴적물과 같은 복모드형 입 도분포의 분석에 매우 유용함이 입증 되었다. 복모드형 입도분포 퇴적물은 제주해협 대륙붕에서는 86%의 높은 비율을 점한다. 종래의 입도특성치(평균, 표준편차, 왜도, 첨도)는 복모드형 입도분포에 대해서는 왜곡된 값을 보인다. 따라서 입도분포의 모드 에 대체로 대응되는 정규성분으로 분해해서 각 정규성분의 특성치를 해석함으로써 입 도특성치에서와 같은 특징의 누락이나 왜곡을 피할 수 있다. 제주해협 대륙붕의 167개 퇴적물 입도분포곡선을 비선형 최소자승법을 사용하여 정규성분으로 분해해서 총 387 개의 정규성분을 얻었다. 정규성분의 평균은 1-3 phi 8-9 phi에 집중되는 것이 많다. 이중 조립질 정규성분의 평균치는 복잡하고 특징적인 지리적 분포를 보인다. 이러한 분포는 퇴적물 총층후 분포와 매우 유사하며 해저면의 지질과 지형을 면밀하게 반영하 고 있다. 해저면을 형성하는 퇴적층은 플라이스토세 후기의 해침성 모래층이며 해저지 형은 플라이스토세말 빙하기 저해수면시기의 침식에 의해 형성된 것으로 보인다.

• 대한기계학회논문집B
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• 제21권3호
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• pp.380-391
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• 1997

A numerical study has been done on the evolution of particle size distribution in particle laden high temperature jet flows undergoing convection, diffusion, thermophoresis and coagulation. The dynamic behavior of these particles have been modelled by approximating the particle size distribution by a lognormal function throughout the process and the moments of the particle size distribution have been used to solve the general dynamic equation. The size distributions of spherical particles in the radial and axial direction have been obtained including the effect of buoyancy. Of particular interests are the variations of geometric mean diameter, number concentration and polydispersity. Results show that buoyancy significantly alters the size distribution in both axial and radial direction. One dimensional analysis for non-spherical particles has also been done and the results have been compared with the existing experimental data.

• 대한화학회지
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• 제51권5호
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• pp.407-411
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• 2007

크기 분포를 가진 금 나노 입자 콜로이드의 소광 스펙트럼을 미 이론으로 계산하고 실험과 비교하였다. 입자 크기 분포를 고려한 계산이 크기 분포를 고려하지 않은 계산보다 실험과 더 가까움을 확인하였다. 최소 자승법을 이용하여 실험에서 얻은 소광 스펙트럼으로부터 입자 크기 분포를 이론적으로 도출하였다. 이렇게 얻은 입자 크기는 입자 지름이 10에서 28 나노미터인 경우 투과전자현미경 분석 결과와 잘 일치하였다.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2012년도 제42회 동계 정기 학술대회 초록집
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• pp.554-554
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• 2012

Controlling the size distribution of gold nanoparticles (NPs) is of great importance due to the fact that their properties are strongly dependent upon the size distribution as well as the size itself. In the citrate reduction method for gold NP synthesis, the citrate works as (1) a reducing agent, (2) a surfactant, and also (3) a weak base: it raises the pH of the whole reaction mixture. Here, we have extensively studied the all three roles of the citrate, by adding other reagents separately (NaBH4, CTAB, and NaOH) for the independent control of the three roles of the citrate. Among the roles of the citrate, that as a weak base was found to be the most critical parameter affecting the size distribution of gold NPs and the size distribution became much more improved with the increase of the solution pH, while adding a supplementary surfactant or reducing agent resulted in the formation of less homogeneous NPs.

• 대한수학회논문집
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• 제10권2호
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• pp.419-438
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• 1995

We investigate a tansient diffusion approximation of queue size distribution in $M^{X}/G^{Y}/c$ system using the diffusion process with elementary return boundary. We choose an appropriate diffusion process which approxiamtes the queue size in the system and derive the transient solution of Kolmogorov forward equation of the diffusion process. We derive an approximation formula for the transient queue size distribution and mean queue size, and then obtain the stationary solution from the transient solution. Accuracy evalution is presented by comparing approximation results for the mean queue size with the exact results or simulation results numerically.

• 생명과학회지
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• 제7권4호
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• pp.355-357
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• 1997

대립종자와 소립종자의 cross부터 F$_{2}$와 F$_{3}$ 세대에서의 종자크기에 대한 빈도분포의 다음과 같다. 두 세대에서 모본의 크기와 같은 progeny는 나타나지 않았으며 각 세대의 평균치는 양 모본의 평균치 보다 낮았다. 소립종자 크기에 비해 우성적인 유전양상을 나타 내었다.

• 산업경영시스템학회지
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• 제27권4호
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• pp.23-32
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• 2004

This paper addresses a model for the transportation planning that determines the transportation cycle time and the vehicle size to minimize the cost in a distribution system. The vehicle routing to minimize the transportation distance of the vehicles is also determined. A distribution system is consisted of a distribution center and many retailers. Products are transported from distribution center to retailers according to transportation planning. A model is assumed that the time horizon is continuous and infinite, and the demand of retailers is constant and deterministic. Cost factors are the transportation cost and the inventory cost, which the transportation cost is proportional to the transportation distance of vehicle when products are transported from distribution center to retailers, and the inventory cost is proportional to inventory amounts of retailers. A transportation cycle time and a vehicle size are selected among respective finite alternatives. The problem is analyzed, and a illustrative example is shown.

• 복식문화연구
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• 제8권4호
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• pp.549-561
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• 2000

The purpose of this study was to survey and analyze the age classification of women customers as a target market and sizes on a label that were actually produced by each brand in Korean national brands ; they were classified into size for bodice and bottom, and compared with the distribution of national data of women's body measurement. They were analyzed and classified by brand groups of 'miss', 'missy', 'Mrs.'and 'madam', The results were ; 1) It was found that recent products for ready-made for women's clothes tend to be designed with target to the measured ages classified by the range of five or ten years. The main practice was that for 'miss'brand group the age range was of five years, and for 'missy'brand group, ten years. And for 'Mrs'and 'madam'brand groups, it was of 15 or 20 years. So that, it is necessary to design their clothes based on their features of body considering the intervals of age. 2) 'Mrs'and 'madam'groups were most remarkable for their distribution into a vast range of sizes for three control dimensions and waist girth size when compared to 'miss'and 'missy'groups. The distribution of brand size had no relation with that of body measurement, and in particular, none was produced for short height size between 145 and 150 ㎝. For tall height size between 175 and 180 ㎝, many brand sizes were distributed while body measurement was few. It means that distribution of brand size was different from real distribution of body measurement was few. It means that distribution of brand size was different from real distribution of body measurement as a result that the larger the bust girth in such cases over 160 ㎝, the larger the size of hip girth. Even as for the height 155 and 160 ㎝ in which body measurement is concentrated, there were many problems because while sizes of 'large'bust girth and 'small'hip girth had a large distribution, their clothes were not produced.

• 한국입자에어로졸학회지
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• 제19권4호
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• pp.155-164
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• 2023

APS (Aerodynamic Particle Sizer) and OPC (Optical Particle Counter) have been widely used to real-time measurement of indoor and outdoor aerosols. The APS measures the size distribution based on an aerodynamic diameter, while the OPC uses optical diameter to measure the size distribution of aerosols. Since obtaining a size distribution based on aerodynamic diameter is important to understand aerosol characteristics, lots of researcher had been developed experimental equations which can convert optical diameter into aerodynamic diameter. However, previous studies have conducted repeated experiments on particles having a single diameter. In this study, an experimental method of converting optical diameter into aerodynamic diameter through a single experiment was presented. The collection efficiencies of an axial cyclone were measured using APS and OPC at the same time, and the correlation equation between aerodynamic diameter and optical diameter was driven through a theoretical model. Using the proposed method, the size distribution of NaCl particles measured by OPC showed a high correlation with the size distribution obtained by APS (0.93 of R-squared value). In the tests conducted on ISO A1, A2, and A4 test particles, the converted OPC size distribution tended to be similar to the APS size distribution, and for each of test particles (ISO A1, A2, and A4), the R-squared values for the APS particle size distribution were 0.75, 0.86, and 0.89, respectively.

• 한국지반공학회논문집
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• 제21권7호
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• pp.13-20
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• 2005

본 연구에서는 입도분포가 액상화 저항강도 및 동적물성치에 미치는 영향을 실험적으로 검증하였다. 우리나라 준설매립토의 입도분포 조사를 통해 준설매립토의 보편적인 평균입경 4가지와 균등계수 3가지를 선정하였고 평균입경과 균등계수를 각각 달리한 총 12종류의 대표적 준설매립토의 입도분포를 선정, 시료를 제작하였다. 제작된 시료를 이용하여 진동삼축시험을 수행하여 평균입경과 균등계수가 액상화 저항강도에 미치는 영향을 분석하였다. 또한 공진주시험을 수행하여 입도분포가 동적물성치에 미치는 영향도 분석하였다.