• 한국압력기기공학회 논문집
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• 제11권1호
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• pp.74-78
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• 2015

Nuclear power plant steam generator that is one of the main component has several thousands of thin tubes. And the steam generator tube is subject to damage because of the severe operation conditions such as the high temperature and pressure. Therefore periodic inspections are conducted to ensure the integrity of steam generator component. Hanul unit 3 also has been inspected in accordance with in-service inspection program and is scheduled to be replaced for exceeding the plugging rate which was recommended by manufacturer. During the steam generator replacement activity, we found several clustered porosity on inner surface of main feed water pipe. Additionally crack-like indications were found at weld interface between base material and weld of main feed water pipe. This paper describes the field experience and visual testing results for inner surface of main feed water pipes. The destructive test result had shown that these indications were porosities which were caused by manufacturing process not by operation service.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2004년도 하계학술대회 논문집 Vol.5 No.2
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• pp.1121-1124
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• 2004

Aging test to estimate life property of polymer insulator is executed through several international standard such as IEC 61109 and CEA tracking wheel test, but is not getting clear conclusion yet. There are two methods in the diagnosis method of polymer insulator such as off-line and on-line. The diagnosis methods in off-line are external condition analysis by the eye, contaminant analysis on surface, surface analysis, pollution withstand voltage test, power frequency flashover voltage test, lightning impulse flashover test, tensile fracture load test and flexural load test. The diagnosis methods in off-line most are the method for virgin and last aged sample. However, the diagnosis method in on-line is method that can be evaluate sample state as progressing continuously aging test in beginning, The diagnosis method in on-line is arranged as following: leakage current measurement, electric field, surface state investigation, thermal image, emitting light measurement and then so. In this paper, the tracking performance of polymer insulator with salt solution which is added surface active agent. The diagnosis of insulator sample has been analyzed by leakage current and visual examination.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2005년도 Proceedings of ISRS 2005
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• pp.260-263
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• 2005

This study was carried out to investigate the effects of spatial resolutions on digital image for detecting pine trees damaged by pine wilt disease. Color infrared images taken from PKNU-3 multispectral airborne photographing system with a spatial resolution of 50cm was used as a basic data. Further test images with spatial resolutions of 1m, 2m and 4m were made from the basic data to test the detecting capacity on each spatial resolution. The test was performed with visual interpretation both on mono and stereo modus and compared with field surveying data. It can be conclude that it needs less than 1m spational resolutions or 1m spatial resolutions with stereo pair in order to detect pine trees damaged by pine wilt disease.

• 한국초등과학교육학회지:초등과학교육
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• 제23권4호
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• pp.305-317
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• 2004

The learning materials in elementary school science textbooks should include all kinds of materials being used by both teachers and students in the science teaching. The major purpose of this research is to analysis textbooks and teacher's guidebooks prepared for the science teaching of 3-6 grade students. To clarify this research, we listed whole of the learning materials of science teaching for each grade and counted numbers being used for whole of the lessons of science. And according to the characteristics and the methods of its preparation of materials, the types of learning materials can be divided into 10 categories such as teaching equipments for science, test materials, consumables, audio-visual aids, teaching equipments in general, collecting' recycling materials, field studies' collected data, breeding' cultivation materials, manufacture materials, and etc. At the result of this research, the 7th national science curriculum needs total 844 items of learning materials for science education. They could be separated into ten types of categories such as 159 items of teaching equipments for science, 65 items of test materials, 116 items of consumables, 198 items of audio-visual aids, 64 items teaching equipments in general, 31 items of collecting' recycling materials, 38 items of field studies (collecting) materials, 17 items of breeding-cultivation materials, 58 items of manufacturing materials, 105 items of other materials. And we found out that there were 332 items of materials for the 3rd grade, 303 items for the 4th grade, 324 items for the 5th grade, and 254 items for the 6th grade. The result of this research could be useful for classroom activities for science teaching.

• 한국의상디자인학회지
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• 제22권1호
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• pp.97-111
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• 2020

Classifying clothing fabrics into fashion images lacks research, but is necessary due to the short cycle of fashion and rapidly changing modern trends as consumers seek to satisfy various needs with an increase of online purchases. There is also a lack of research on fashion trend books which attach real fabrics. Therefore, this study aims to help the planning field by recognizing fabric sensibility related to the fabric image perceived by consumers. The data analysis results from descriptive statistics, t-test, and ANOVA using SPSS are as follows: Differences in the visual tactility evaluation related to the consumer recognized fabric images showed more significant differences in F/W seasons. The elegance image was shown as relatively thick, the avant-garde image was shown as relatively heavy, thick fabric. The feminine image was shown as relatively thin and smooth fabric, the sporty images were shown to be moist, flexible and elastic, and the mannish images were relatively rough. The romantic images were shown as relatively thin fabrics. The conclusions inferred from the visual tactile evaluation related to the fabric images recognized by consumers vary by major, so the prior information concerning fabrics and trends can affect the selection of images. The results of this study show that in order to produce clothes suitable for fashion product planning by learning about visual tactility that consumers recognize, fabrics component data displayed in fashion trend books from 2016 to 2018 are needed, so the planner can receive help when selecting the fabrics suitable for each trend.

• 복식문화연구
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• 제20권3호
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• pp.309-318
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• 2012

This study aimed to find the components of visual image by researching main image-related adjectives applied to high-waist skirts. In addition, it compared and analyzed the differences and mutual influences of visual images according to variations in the waistline and skirt length of high-waist skirts. The researchers made nine high-waist skirts-combinations of three different levels of waistlines and skirt lengths. The test involved 121 people who hold degrees in the field of Clothing and Textiles. The panels tested actual images of all models wearing the high-waist skirts shown on a computer screen. The results of the study are as follows.: Four factors affected the visual image as waist-height and skirt-length changed: attractiveness, upper-body compensation, length compensation, and hips compensation. Among these factors, attractiveness was estimated as the most important factor. The torso and the hip were highlighted as the waistline increased from 3cm to 11cm, due to the optical illusion of a tighter skirt wrapping the bust, waist, and hips. As the waistline increased, the stature and leg length increased, possibly revising the overall appearance. For the skirt length, a length measuring 20cm above the knees, proved to be most attractive. This resulted in elongated height and leg length, and a slimmer overall look.

• 한국도로학회논문집
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• 제19권2호
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• pp.25-34
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• 2017

PURPOSES: The purpose of this paper is to evaluate interface performance while using various tack coat materials for asphalt overlay. METHODS : The evaluation was conducted with tracking test, permeability, and interface bond strength. Tracking test was conducted using an image processing technique, to investigate the susceptibility of the tack coat materials. BBS and pull-off test were conducted to evaluate bond strength. The permeability test was conducted to evaluate the effect of tack coat materials. RESULTS : Results reveal that the trackless tack coat material demonstrates less tracking compared to other materials. Moreover, both BBS and pull-off tests can effectively evaluate the bond strength at the interface. RSC-4 was measured less bond strength. Moreover, tack coat prevents water penetration through the surface and aids the extension of the surface life of asphalt pavement. CONCLUSIONS : Trackless tack coat demonstrated a high and consistent bond strength performance. The tack coat types demonstrate marginally different performance as function of curing times. Field applicability was tested based on visual observation. Therefore, these should be considered when trackless tack coat is slightly enhanced the pavement performance based on limited this study results. Finally, it is necessary to allow reasonable time for the tack coat to completely cure.

• 컴퓨터교육학회논문지
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• 제4권1호
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• pp.99-107
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• 2001

수학교육에서 기하교육의 주된 목적 중 하나는 기하학적 직관능력과 그것을 바탕으로 한 논리적인 추론능력을 향상시키는 것이다. 직관과 관련된 시각적인 요소는 기하의 교수학습에서 중요한 역할을 한다. 따라서, 본 연구는 시각적 요소에 대한 동적인 조작이 가능한 멀티미디어 타이틀을 개발하고 그 효과를 검증하는데 목적이 있다. 중학교 3학년 과정의 "피타고라스의 정리 및 그 활용"을 학습하기 위한 본 타이틀은 Toolbook으로 설계 및 구현하였으며 개별학습이 가능하고 학교 현장에 적용할 수 있다. 그리고 중학교 2학년을 대상으로 적용집단과 비교집단으로 구분하여 수업을 실시하고 학업성취도 평가와 설문조사를 실시하였다. 두 집단의 학업성취도를 SPSS를 사용하여 t-test를 실시한 결과 적용집단이 비교집단에 비하여 학업성취도가 높은 것으로 나타났으며, 시각적인 요소에 대한 동적인 조작 가능성의 제공은 학습자에게 매우 높은 학습효과를 지각하게 하고 지적 능력 향상에 도움이 되는 것으로 나타났다.

• 한국농공학회지
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• 제32권E호
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• pp.67-73
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• 1990

Many distress mechanisms in pavement are known to be caused by the poor mechanical properties of bituminous concretes. Among many mechanical properties, tensile strength is one of the more important indicates that represent the resistance of pavement to traffic loading. However, there has been no relationship established between the strength and distress mechanisms. Therefore, this study was conducted to evaluate a correlation between the tensile strength value and the intensity of distress in bituminous concrete. Distress data were collected from an extensive field investigation over 77km of a four-lane highway in South Carolina, USA, and from laboratory prepared specimens in two phases of study. Strength data were obtained from a total of more than 400 field cores taken from the same highway and from 640marshall specimens of surface course mixture prepared in the laboratory. These data were analyzed using statistical test techniques. It was found from statistical analyses that the tensile strength of bituminous concrete had a strong relation with the pavement condition in the field. In the analysis of rutting and stripping, low strength concrete showed a higher distress rate in the mixture, and mixtures under distress in the field showed obviously reduced strength values. Stripping was found to be the most significant distress mechanism that was correlated with low strength bituminous concrete. Rutting appeared more frequently in a low strength pavement section of the highway as a sign of failure due to traffic loading.

• 터널과지하공간
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• 제28권5호
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• pp.493-511
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• 2018

본 논문에서는 그라운드 앵커의 긴장력 손실에 대응하고자 긴장력 상시확인을 위한 앵커 긴장력 상시 육안확인장치에 대한 내용을 다루었다. 그라운드 앵커는 사회적 인프라 시설의 안정성을 확보하기 위해 시공되었지만 지속적인 긴장력 손실로 인해 시설물에 대한 안전이 심각하게 우려되고 있는 실정이다. 이에 앵커의 유지관리가 요구되지만 현재 잔존긴장력의 계측은 경제적인 측면을 고려하여 표본조사로 이루어지고 있어 정밀도에 대한 한계점을 지니고 있다. 따라서 본 논문에서는 앵커의 긴장력을 육안으로 확인할 수 있는 앵커 긴장력 상시 육안확인장치의 개발을 목적으로 개념설계, 실내 인장실험을 통한 규격화를 수행하였으며, 현장시험을 통해 성능을 확인하였다.