• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2001년도 춘계학술대회 논문집
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• pp.483-486
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• 2001

Rapid Prototyping(RP) has been widely applied in designing and developing processes a new product. The functional requirements of a rapid prototyping system are high speed and high accuracy, and they depend on the operating parameters, some of which can be set by users. The accuracy is evaluated by dimensional errors and form errors of manufactured pars. A specially designed specimen with various features has been used for the accuracy evaluation. According to the Taguchi experimental design techniques, and orthogonal array of experiments has been set which has the least number of experimental runs to find the parametric effects. A laser scanner is used to obtain the point data of the parts and Surfacer is used to determine the lengths and angles. The conditions for the FDM manufacturing parametrs have been found.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 1997년도 추계학술대회 논문집
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• pp.83-86
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• 1997

Even as many methods and technologies have been introduced on data generation, parts orientation and layer slicing to acquire the rapid prototyping(RP) parts that have useful surface to satisfy customers' needs such as stylingldesign verification directionlindirect tooling directly from the RP machine, these trials continue to suffer from the surface roughness due to the build characteristics of RP technology. A new postprocess finishing method is suggested in this paper to overcome the surface roughness problem on the surface of the RP parts. To prevent deterioration of dimensional accuracy from the conventional grinding-only, and coating-grinding methods, 4-step surface finishing process is applied. To satisfy the various requirements from the RP oriented industrial f elds, effective procedure, coating material, grmd~ng tools and methods are employed.

• 콘크리트학회논문집
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• 제11권4호
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• pp.117-127
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• 1999

In concrete incorporating high volume ground granulated blast-furnace slag that has frozen at early age, to evaluated the results of resistance to freezing and thawing is very difficult because the hydration of the concrete increases over the duration of rapid freezing and thawing test. Hence, the dynamic modulus of elasticity of specimens after freezing and thawing will be favorable results unless the hydration effect is taken into consideration. In this study, a method of evaluating to the resistance to freezing and thawing of concrete subjected freezing at early age, in which the effect of hydration is modified for its increase during rapid freezing and thawing test, is investigated.

• 한국의학물리학회지:의학물리
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• 제28권4호
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• pp.181-189
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• 2017

The conventional delivery quality assurance (DQA) process for RapidArc (Varian Medical Systems, Palo Alto, USA), has the limitation that it measures and analyzes the dose in a phantom material and cannot analyze the dosimetric changes under the motional organ condition. In this study, a DQA method was designed to overcome the limitations of the conventional DQA process for internal target volume (ITV) based RapidArc. The dynamic DQA measurement device was designed with a moving phantom that can simulate variable target motions. The dose distribution in the real volume of the target and organ-at-risk (OAR)s were reconstructed using 3DVH with the ArcCHECK (SunNuclear, Melbourne, USA) measurement data under the dynamic condition. A total of 10 ITV-based RapidArc plans for liver-cancer patients were analyzed with the designed dynamic DQA process. The average pass rate of gamma evaluation was $81.55{\pm}9.48%$ when the DQA dose was measured in the respiratory moving condition of the patient. Appropriate method was applied to correct the effect of moving phantom structures in the dose calculation, and DVH data of the real volume of target and OARs were created with the recalculated dose by the 3DVH program. We confirmed the valid dose coverage of a real target volume in the ITV-based RapidArc. The variable difference of the DVH of the OARs showed that dose variation can occur differently according to the location, shape, size and motion range of the target. The DQA process devised in this study can effectively evaluate the DVH of the real volume of the target and OARs in a respiratory moving condition in addition to the simple verification of the accuracy of the treatment machine. This can be helpful to predict the prognosis of treatment by the accurate dose analysis in the real target and OARs.

• 디자인학연구
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• 제13권2호
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• pp.103-109
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• 2000

실 제품을 제작하기 전 컴퓨터를 이용해 프로토타이프를 제작해 미리 제품은 평가하는 방법이 널리 사용되고 있다. 프로토타이핑 작업으로 제품의 외관을 미리 평가하는 부분은 이미 실효성을 입증 받았다. 그러나 사용자 인터페이스(User Interface) 디자인 부분에 대한 평가에서는 아직 그 유효성에 대한 연구가 충분하지 못한 형편이다. 본 연구는 프로토타이핑 방법에 의한 사용자 인터페이스 디자인 평가가 과연 적절한 방법이 될 수 있는 지에 대해 실험적 검정을 수행하였다. 대상이 되는 제품으로 전자렌지를 선택했으며 이를 컴퓨터를 이용해 프로토타이프를 제작했다. 12명의 피실험자들을 나누어 실 제품과 프로토타이프에 대한 사용성 평가를 수행하였고 그 결과를 분석하였다. 분석 결과 실 제품과 프로토타이프 사이에 작업성공률, 작업수행시간, 버튼 조작 회수 등에 차이가 있는 것으로 밝혀졌다. 이는 아직도 프로토타이핑 방법이 사용성 평가 도구로 사용하기에는 보완해야할 점이 많이 있다는 것을 의미한다. 토의에서는 이에 대한 원인 규명과 문제점 해결을 위한 보완 사항 등을 제시하였다. 본 연구의 결과는 현장에서 래피드 프로토타이핑 방법을 적용해 제품의 사용성 평가를 수행하려는 디자이너들에게 도움을 줄 수 있을 것이다

• 한국물환경학회지
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• 제30권3호
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• pp.329-339
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• 2014

This study aims to estimate chlorophyll-a concentration in rivers using multi-spectral RapidEye imagery and Spectral Mixture Analysis (SMA) and assess the applicability of SMA for multi-temporal imagery analysis. Comparison between images (acquired on Oct. and Nov., 2013) predicted and ground reference chlorophyll-a concentration showed significant performance statistically with determination coefficients of 0.49 and 0.51, respectively. Two band (Red-RE) model for the October and November 2013 RapidEye images showed low performance with coefficient of determinations ($R^2$) of 0.26 and 0.16, respectively. Also Three band (Red-RE-NIR) model showed different performance with $R^2$ of 0.016 and 0.304, respectively. SMA derived Chlorophyll-a concentrations showed relatively higher accuracy than band ratio models based values. SMA was the most appropriate method to calculate Chlorophyll-a concentration using images which were acquired on period of low Chlorophyll-a concentrations. The results of SMA for multi-temporal imagery showed low performance because of the spatio-temporal variation of each end members. This approach provides the potential of providing a cost effective method of monitoring river water quality and management using multi-spectral imagery. In addition, the calculated Chlorophyll-a concentrations using multi-spectral RapidEye imagery can be applied to water quality modeling, enhancing the predicting accuracy.

• Journal of Veterinary Science
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• 제22권3호
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• pp.40.1-40.12
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• 2021

Background: The microsporidian parasite Nosema ceranae is a global problem in honeybee populations and is known to cause winter mortality. A sensitive and rapid tool for stable quantitative detection is necessary to establish further research related to the diagnosis, prevention, and treatment of this pathogen. Objectives: The present study aimed to develop a quantitative method that incorporates ultra-rapid real-time quantitative polymerase chain reaction (UR-qPCR) for the rapid enumeration of N. ceranae in infected bees. Methods: A procedure for UR-qPCR detection of N. ceranae was developed, and the advantages of molecular detection were evaluated in comparison with microscopic enumeration. Results: UR-qPCR was more sensitive than microscopic enumeration for detecting two copies of N. ceranae DNA and 24 spores per bee. Meanwhile, the limit of detection by microscopy was 2.40 × 10⁴ spores/bee, and the stable detection level was ≥ 2.40 × 10⁵ spores/bee. The results of N. ceranae calculations from the infected honeybees and purified spores by UR-qPCR showed that the DNA copy number was approximately 8-fold higher than the spore count. Additionally, honeybees infected with N. ceranae with 2.74 × 10⁴ copies of N. ceranae DNA were incapable of detection by microscopy. The results of quantitative analysis using UR-qPCR were accomplished within 20 min. Conclusions: UR-qPCR is expected to be the most rapid molecular method for Nosema detection and has been developed for diagnosing nosemosis at low levels of infection.

• 한국안전학회지
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• 제12권4호
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• pp.180-190
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• 1997

A new method in the fault tree analysis (FTA) for the reliability calculation is suggested. Two steps are necessary in traditional method in evaluation of the occurrence probability of top event in fault tree (FT). The first step is to find the minimal outsets, and the second one is to substitute the result into the poincare equation. In order to reduce the enormous computing time of this method, lots of rapid algorithms have been developed. Almost of all achievements were, however, based on the partial structural properties of FT. In this paper, the FT is transformed to a non-linear graph G which has the same minimal outsets of original n, and then the reliability is calculated using the domination theory. In this new method, the required number of equation terms are at most $2^n$ (n is node number of graph G), while $2^m$-1 (m is the number of minimal cutsets) calculation terms are required in the poincare equation in traditional method. Since m>>n in general. our new method reduces the calculation time significantly.

• 한국작물학회지
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• 제38권1호
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• pp.66-71
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• 1993

자동분석기(Rapid Ftow Autoanalyzer) RF A-300을 이용한 쌀의 아밀로스 분석법을 확립하였다. 자동분석기로 분석한 아밀로스 함량을 Williams나 Juliano 등의 방법에 따른 분석결과와 비교하여 본 결과 매우 높은 직선적인 상관관계 (r=0.95$^{**}$-0.97$^{**}$)를 나타내었다. 자동분석기를 이용한 분석법으로 얻어진 아밀로스함량은 Juliano등의 분석법에 의해 얻어진 결과에 비해 저ㆍ중 아밀로스 품종에서는 1.0-2.0%가 높게, 고 아밀로스품종에서는 1%정도 낮게 측정된 반면 Williams등의 분석법에 따른 검정결과에 비해서는 2.0-5.0% 정도로 높은 함량을 나타내었는데 검정치가 저 아밀로스품종 쪽일수록 증가정도가 약간 큰 경향이었다. 세가지 분석방법간에 상호 직선적인 상관을 보이면서 쌀가루에 비해 녹말시료에서 아밀로스함량이 약간 높은 경향이었다.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2005년도 춘계학술대회 논문집
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• pp.738-742
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• 2005

Rapid Prototype has been used to design and Production of part in a variety of fields ; Car, Electronic products, Aviation, Heavy industry etc. Moreover development of hardware gave rise to use the method of Rapid Prototype more and more at high precision and complicated shapes. Expecially, to be using process of products that shapes of Micro-hole ; Cellular phones, Antennas, Jewels, Semi conductor cases. In case of Micro-shape, precision of the shape turns on various condition ; Laser size, Laminate height, scanning speed, overcure, viscosity of resin, etc. Sometimes breaks out the case that interner hole of shape is blocked by viscosity of resin. The phenomenon has solved easily to reduce viscosity of resin. But, in case of the method brings about the problem that strength goes down in actuality products hardening. This study on verify to change of shape of Micro-hole and makes the semiconductor case which has shape of Micro-hole by using resin of higher viscosity, scanning speed and overcure