• 한국안광학회지
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• 제4권2호
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• pp.73-79
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• 1999

안경렌즈의 재질개발에서 중요하게 고려하는 것 중 하나는 높은 굴절률을 갖는 물질을 개발하는 것이다. 본 연구에서는 비교적 값싸면서 쉽게 굴절률을 얻을 수 있는 굴절률 측정법으로 Michelson 간섭계에 의한 평판시료의 굴절률 측정장치를 고안하고 이론식을 도출하였다. 고안된 굴절률 측정장비로 굴절률을 측정한 결과 BK7의 굴절률은 $n_{6328}$=1.5159으로 측정되어 참고문헌의 값과 0.001정도의 굴절률 오차를 나타내었다. 또한 용융석영의 굴절률은 $n_{6328}$=1.4528로 측정되어 참고문헌의 값과 0.003정도의 오차를 보이고 있다. 그러므로 본 연구에서 고안된 Michelson 간섭계에 의한 평판시료의 굴절률 측정장치는 굴절률 측정법으로 유용한 것으로 나타났다.

• Earthquakes and Structures
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• 제12권6호
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• pp.673-687
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• 2017

A three-dimensional; structural health monitoring; vertical; planar; cross-sample entropy; multiscaleA three-dimensional structural health monitoring (SHM) system based on multiscale entropy (MSE) and multiscale cross-sample entropy (MSCE) is proposed in this paper. The damage condition of a structure is rapidly screened through MSE analysis by measuring the ambient vibration signal on the roof of the structure. Subsequently, the vertical damage location is evaluated by analyzing individual signals on different floors through vertical MSCE analysis. The results are quantified using the vertical damage index (DI). Planar MSCE analysis is applied to detect the damage orientation of damaged floors by analyzing the biaxial signals in four directions on each damaged floor. The results are physically quantified using the planar DI. With progressive vertical and planar analysis methods, the damaged floors and damage locations can be accurately and efficiently diagnosed. To demonstrate the performance of the proposed system, performance evaluation was conducted on a three-dimensional seven-story steel structure. According to the results, the damage condition and elevation were reliably detected. Moreover, the damage location was efficiently quantified by the DI. Average accuracy rates of 93% (vertical) and 91% (planar) were achieved through the proposed DI method. A reference measurement of the current stage can initially launch the SHM system; therefore, structural damage can be reliably detected after major earthquakes.

• 천문학회보
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• 제39권2호
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• pp.56.2-56.2
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• 2014

We present an extensive study of the environment of galaxies with bars in the low-redshift Uni-verse, using a volume-limited sample of over 30,000 galaxies drawn from the Sloan Digital Sky Survey, with visually-determined morphological classifications and bar identifications. We use four different statistics to quantify the environment of our galaxies: the projected two-point cross-correlation function with respect to a spectroscopic sample of reference galaxies, the background-subtracted number count of galaxies in a deep photometric sample in the vicinity of our galaxies, the overdensity of the local environment estimated at ~3 Mpc scale from the three-dimensional reconstruction of the cosmic density field of the local Universe, and the membership of our galaxies in the SDSS galaxy groups to segregate central to satellite systems. We find a weak, but significant trend for early-type galaxies with a bar to be more strongly clustered on scales from a few 100 kpc to 1 Mpc, when compared to early-type galaxies without a bar. For late-type galaxies, we find less neighbours within ~50 kpc around the barred late-types when compared to the unbarred late-types. For late-type galaxies we also detect a decrease of the bar fraction for dark matter dominated systems, and finally we find no obvious correlation between the overdensity and the fraction of barred galaxies in our sample.

• 한국염색가공학회지
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• 제26권4호
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• pp.339-346
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• 2014

To give a positive effect on dispersion behavior of high performance fibers $Vectran^{(R)}$ in water with reference to wet-laid nonwoven technology, 9 kinds of sulfonate type anionic surfactants were chosen to study. After dispersion experiment, the number and the area occupied by fibers in each sample were counted and figured to calculate the index of dispersion in conjunction with quadrat analysis. Similar tendency was observed in the results of two experiments. The sample without addition of any surfactant resulted in the most aggregated dispersion behavior. As the length of alkyl group attached to sulfonate increases, the sample shows more dispersed behavior. The sample with the surfactant having the aryl group and the longer alkyl group shows the most dispersed behavior and it can be seen with the naked eye as well.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제13권2호
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• pp.771-789
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• 2019

Text detection has been a popular research topic in the field of computer vision. It is difficult for prevalent text detection algorithms to avoid the dependence on datasets. To overcome this problem, we proposed a novel unsupervised text detection algorithm inspired by bootstrap learning. Firstly, the text candidate in a novel form of superpixel is proposed to improve the text recall rate by image segmentation. Secondly, we propose a unique text sample selection model (TSSM) to extract text samples from the current image and eliminate database dependency. Specifically, to improve the precision of samples, we combine maximally stable extremal regions (MSERs) and the saliency map to generate sample reference maps with a double threshold scheme. Finally, a multiple kernel boosting method is developed to generate a strong text classifier by combining multiple single kernel SVMs based on the samples selected from TSSM. Experimental results on standard datasets demonstrate that our text detection method is robust to complex backgrounds and multilingual text and shows stable performance on different standard datasets.

• 한국진공학회지
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• 제22권5호
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• pp.231-237
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• 2013

본 연구에서는 분동식 기준압력계의 기준분동(reference weight)의 부피를 측정하는 새로운 측정방법인 기체용적계(gas pycnometer) 측정방법을 제안하였다. 제안된 측정방법에 의한 측정결과로서 기준분동 1 kg, 2 kg, 5 kg에 대한 부피 측정불확도는 신뢰수준 95%에서 0.2%를 나타내었다. 기체용적계의 주요 장치는 샘플용기와 팽창용기, 정밀압력계, 정밀온도계, 진공펌프로 구성되며, 측정 원리는 일정한 용기 내에 들어 있는 일정한 양의 기체의 압력과 부피는 서로 반비례한다는 보일(boyle's law)의 법칙을 용용하였다. 본 결과는 현재까지 문헌이나 제조사로부터 기준분동 재질에 대한 밀도값을 적용하여 오던 것을 기준분동의 부피를 직접 측정하여 밀도값을 적용함으로서 압력기준기의 압력 기준값에 대한 국가측정표준의 신뢰도 향상에 기여될 것이다.

• 한국도서관정보학회지
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• 제36권2호
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• pp.283-305
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• 2005

과학기술데이터는 엄격한 평가기준에 의해 신뢰성과 정확성이 보장된 참조표준(standard reference data) 값을 지닐 수 있어야 한다. 참조표준은 측정표준을 바탕으로 구하여진 결과 값을 표준화시키는 작업으로서 데이터의 생산조건, 실험환경. 측정방법, 데이터 처리 등이 검토되어 참조데이터(reference data)와 구분된다. 참조표준은 "공인된 수치데이터"로 표현되고 이는 측정결과의 신뢰도를 정량적으로 나타내는 불확도 (uncertainty)로 표기된다. 본 연구에서는 참조표준에 대한 의미를 이해하고, 평가되지 않은 과학기술 데이터가 어떤 평가 과정을 거쳐 참조표준으로 분류되는지를 알아보기 위해 소재물성분야를 예로 살펴보았다. 그리고 국가 참조표준을 본격적으로 운영하기 위한 방안으로 국가참조표준센터, 데이터센터, 위원회의 역할과 임무, 이를 뒷받침하기 위한 법적. 제도적 방안을 제시하였다.

• 한국소프트웨어감정평가학회 논문지
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• 제7권1호
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• pp.29-39
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• 2011

프로그램 내의 코드클론을 찾아주는 도구나 기술들을 평가하기 위해서는 해당 도구가 탐지하는 못하는 클론이 있는지 확인해야 한다. 이를 위해서 샘플 소스코드에 대해서 코드클론을 모두 모아놓은 표준 표본 집합체가 필요하다. 그런데 기존의 코드클론 표본 집합체는 여러 클론탐지 도구의 결과들을 참조해 수작업으로 구축하지만 평가 기준으로 사용하기에는 빠져있는 표본이 많다. 본 연구에서는 자동으로 코드클론 표본 집합체를 생성하는 방법을 제안하고 도구를 구현하였다. 이 도구는 프로그램 소스를 핵심구문트리로 변환한 뒤, 트리를 샅샅이 비교하여 클론 패턴을 찾아낸다. 본 도구는 오탐이 없으며, 특정한 패턴을 제외하고 미탐도 없어서 코드클론 표본 집합체를 자동으로 생성하기 적합하다. 실험결과 상용도구인 CloneDR에서 찾아낸 클론을 모두 포함하면서 2-3배 더 많은 클론들을 찾아내었고, Bellon의 기존 표본 집합체의 클론들을 거의 대부분 포함(93-100%)하면서 자동 구축한 표본 집합체의 크기가 훨씬 크다.

• 대한치과교정학회지
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• 제23권4호
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• pp.565-606
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• 1993

The purpose of this study was to evaluate the change of before and after treatment of anterior openbite malocclusions treated by Multiloop Edgewise Archwire technique. The openbite sample consisted of 4 male and 12 female adults, treated with nonextraction or third molar extraction. The normal sample consisted of 58 subjects, which have pleasing facial profile and normal occlusion and no experience of orthodontic or prosthodontic treatment. The 58 subjects of normal sample were subdivided by cephalemetric vertical relationship of face. The 40 subjects, cephalometric vertical relationship of face was in normal range, classified as Normal Sample group 1. The 18 subjects, increased cephalometric vertical relationship of face, classified as Normal Sample group 2. The computerized cephalometric analysis was accomplished with 50 reference points for 22 skeletal measurements, 46 dentoalveolar measurements, 8 soft tissue measurements. Statistical analysis of the data was carried out with paired t-test, Student's t-test, and DUNCAN test using SAS(PC version), The results were as follows : 1. There were no statistically significant differences in skeletal measurement between before and after treatment. The major changes were in dentoalveolar region. 2. After treatment, the long axis of maxillary and mandibular posterior teeth were distally tipped-back, and uprighted to bisected occlusal plane. The interincisal angle was increased. 3. There were no statistically significant increase in the upper posterior dental height and statistically significant decrease in the lower posterior dental height. The upper anterior dental height was increased, but there was no statistically significant increase in the absolute upper anterior dental hight. The lower anterior dental height was increased. 4. After treatment, the maxillary occlusal plane to palatal plane angle and the mandibular occlusal plane to mandibular plane angle were statistically significant increased. Then, there were no statistically significant difference between after treatment group and normal sample group 2. 5. After treatment, the percentage of upper lip length to upper anterior dental height was decreased. Then, There were no statistically significant difference between after treatment group and normal sample group 2.

• 한국작물학회지
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• 제56권1호
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• pp.88-93
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• 2011

This experiment was carried out to find suitable sample type for the more accurate prediction and non-destructive way in the application of near infrared reflectance spectroscopy (NIRS) technique for estimation the protein, total amino acids, and total isoflavone of soybean by comparing three different sample types, single seed, whole seeds, and milled seeds powder. The coefficient of determination in calibration ($R^2$) and coefficient of determination in cross-validation (1-VR) for three components analyzed using NIRS revealed that milled powder sample type yielded the highest, followed by single seed, and the whole seeds as the lowest. The coefficient of determination in calibration for single seed was moderately low($R^2$ 0.70-0.84), while the calibration equation developed with NIRS data scanned with whole seeds showed the lowest accuracy and reliability compared with other sample groups. The scatter plot for NIRS data versus the reference data of whole seeds showed the widest data cloud, in contrary with the milled powder type which showed flatter data cloud. By comparison of NIRS results for total isoflavone, total amino acids, and protein of soybean seeds with three sample types, the powder sample could be estimated for the most accurate prediction. However, based from the results, the use of single bean samples, without grinding the seeds and in consideration with NIRS application for more nondestructive and faster prediction, is proven to be a promising strategy for soybean component estimation using NIRS.