• Title/Summary/Keyword: Measuring dimension

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Measuring library online service quality: An application of e-LibnQual (도서관의 온라인 서비스 품질 평가: e-LibQual의 적용)

  • 강회일;정용길
    • Journal of the Korean Society for information Management
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    • v.19 no.3
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    • pp.237-261
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    • 2002
  • The purpose of this study is to measure the library online service quality based on the expectation and the service performance from the users' point of view. The online questionnaire was developed based on SERVQUAL, however information quality dimension was added on it, and the survey was conducted within a research library. The factor analysis for effecting library online services showed that 5 service dimensions were loaded discretely, and information quality was put in the other dimension. The IPA (Important Performance Analysis) result confirmed that information quality, service reliability, and service assurance were considered as important factors : multiple regression analysis revealed that tangibility and information quality were the most significant dimension for the library online service.

Estimate for Ensuring sight Distance of Curve Section from Consideration of the Environmental Impact Assessment based on the 3D GIS (3차원 GIS기법으로 환경영향을 고려한 곡선부 시거 안정성 분석)

  • Choi Hyun
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.10 no.4
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    • pp.700-705
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    • 2006
  • The latest system of GIS has been changing from 2 dimension to 3 dimension. According to the rapid growth of the fields linked to 3D GIS, 3D GIS has variously affected the public field, the national defense field. and the industrial field. This study estimated sight distance safety of curve section considering the environmental impact based on 3D GIS. Sight distance is calculated from the relation between road which keeps the three-dimension character and driver gaze, so it needs to consider both plane and vertical for the accurate measuring. This study made analysis of the sight distance through considering the environmental impact with driving simulation of design speed 80km/h and running speed 60-120km/h.

Non-contacting OMM (On Machine Measurement) based on CAD Model (CAD 모델 기반 비접촉 기상 측정에 관한 연구)

  • 권세진;이정근;박정환;고태조;김선호
    • Journal of the Korean Society for Precision Engineering
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    • v.20 no.11
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    • pp.134-141
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    • 2003
  • An industrial product is designed and fabricated, followed by the inspection process in order to check whether it is dimensionally tolerable or not. The machining process produces a part such as a mold or die, in which the three-dimensional coordinate might be measured by a CMM (Coordinate Measuring Machine) for assessment of its dimension. It is not ignorable, however, that a CMM measurement requires a lot of operating time and cost, which has led to many studies on the OMM system. The OMM system can be categorized into contact and non-contact types, and each of which has its own strengths and weaknesses. Non-contacting types generally utilize structured lights, sounds or magnetic fields. Though they show rather poor performance in positional accuracy, the measuring speed is faster than the contacting probes. This paper presents the development of an OMM system based on a non-contacting laser displacement sensing apparatus and CAD model. The system is composed of software modules of center-aligning and measuring, which has been operated and verified on a NC machining center on a shop floor.

Analysis of Master Dimensional Shape Error Rate According to Reverse Engineering Technique (역설계 방법에 의한 시편 치수 형상의 오차율 분석)

  • Jung, Hyun-Suk;Park, Su-Jung;Yoo, Joong-Hak
    • Journal of the Korean Society of Manufacturing Technology Engineers
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    • v.25 no.5
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    • pp.393-399
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    • 2016
  • In this study, an experiment was conducted using a 3D scanner, commonly used in reverse engineering techniques, and the newly introduced CT measuring machine. The hole, width, and angle of specimens having various shapes were designated, the error rates in dimensional modelling generated during scanning with each device were compared, and the models were printed using a 3D printer. A secondary comparative analysis of the two printed specimens was conducted; the causes of dimension errors that occur during the printing process after scanning with each device and the differences associated with variation in shape were also analyzed. Based on the analysis results, the featured shape for each scanning application method and issues to consider in reverse engineering were presented, and the use of the CT measuring machine was recommended as a method to minimize error rates in dimensions and ensure efficient reverse engineering.

A Simulation of Arching Earth Pressure Exerted on Vertical Shafts through Centrifuge Tests (원심모형실험에 의한 수직구 아칭토압 모사)

  • Lee, Dae-Soo;Kim, Kyoung-Yul;Hong, Sung-Yun;Kim, Yoo-Suk
    • Proceedings of the Korean Geotechical Society Conference
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    • 2010.09a
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    • pp.1073-1080
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    • 2010
  • In this paper, the centrifuge model tests were conducted for the sake of measuring three dimensional arching earth pressure while two step excavation of the vertical shaft. The results of the centrifuge model tests were compared to newly suggested arching earth pressure equation proposed by Kim et al(2009) and two dimension earth pressure(Rankine). As the results, Measured arching earth pressure revealed about 35 percentages of two dimension earth pressure(Rankine) and almost same as that of newly suggested arching earth pressure equation.

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Camera Focal Length Measuring Method and 3-Dimension Image Correspondence of the Axial Motion Model on Stereo Computer Vision (3-Dimension 영상을 이용한 카메라 초점측정 및 동일축 이동 모델의 영상 정합)

  • 정기룡
    • Journal of the Korean Institute of Navigation
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    • v.16 no.3
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    • pp.77-85
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    • 1992
  • Camera arrangement for depth and image correspondence is very important to the computer vision. Two conventional comera arrangements for stereo computer vision are lateral model and axial motion model. In this paper, using the axial motion stereo camera model, the algorithm for camera focal length measurement and the surface smoothness with the radiance-irradiance is proposed fro 3-dimensional image correspondence on stereo computer vision. By adapting the above algorithm, camera focal length can be measured precisely and the resolution of 3-dimensional image correspondence has been improved comparing to that of the axial motion model without the radiance-irradiance relation.

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A Study on Transition of Dimension Error and Surface Precision in High Speed Machining of Al-alloy (Al 합금의 고속가공에서 치수오차와 표면정도 추이고찰)

  • 정문섭
    • Journal of the Korean Society of Manufacturing Technology Engineers
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    • v.9 no.3
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    • pp.96-102
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    • 2000
  • High speed machining aims to raise the productivity and efficiency by making more precise and higher value-added products than any other machining method by means of the high speediness of spindle and feed drive system. The purpose of this study is to investigate the effects of the run-out of endmill on the dimension precision of workpiece and to obtain the fundamental data on high speed machining which is available by machining the side of Al-alloy with solid carbide endmills in high speed machining center and by measuring dimensions and surface roughness. From the results of experimentation following are obtained ; if spindle speed is ultra high in conditions that radial depth of cut and feed per tooth are very small highly precise and accurate products are to be made efficiently with high feed rate. and so we can raise productivity.

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Hofstede Cultural Dimension Measuring through World Values Surveys (World Value Surveys를 활용한 Hofstede 문화차원 측정과 활용에 관한 연구)

  • Kang, Mi-Young;Kwon, Jong-Wook
    • Asia-Pacific Journal of Business
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    • v.9 no.2
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    • pp.137-152
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    • 2018
  • Hofstede cultural value model is one of the most influential model for cross-cultural studies to measure national difference. In this study, we examine that Hofstede Cultural Dimensions can be measured by World Value Surveys. Selected WVS questions for 31 measurable countries after Exploratory Factor Analysis(EFA) and Confirmatory Factor Analysis(CFA), approved valid through empirical analysis. It is applicable that Individualism values(IND) has related to 2 questionnaires including life satisfaction, Power Distance values(PDI) to 2 questionnaires about political action(Signing a petition and Joining in boycotts), Masculinity values(MAS) to 2 sexual-role questionnaires like "University is more important for a boy than for a girl", Uncertainty Avoidance values (UAI) to 3 questionnaires about confidence(Parliament, The Political parties and Justice System), Long-Term Oriented values(LTO) to 4 questionnaires including "How proud of nationality" and Indulgence versus Restraints values (IVR)to 2 questionnaires including Feeling of Happiness.

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An Experimental Study on the Long-Term Performance Variation of the Plate-Type Enthalpy Exchange Element Made of Paper (판형 종이 재질 전열교환 소자의 장기 성능 변화에 대한 실험적 연구)

  • Kim, Nae-Hyun
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.28 no.4
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    • pp.165-170
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    • 2016
  • Long-term performance of the enthalpy exchange element is a topic of current interest due to the concern of possible performance degradation over time. In this study, a 350 CMH enthalpy recovery ventilator equipped with an enthalpy exchange element was installed in an office room, and the performance has been traced over the past 5 years. The appearance, overall dimension, thermal performance, leakage ratio and anti-bacterial performance were checked annually. Results showed that the change in thermal performance (sensible, latent and enthalpy efficiency) was negligible with periodic cleaning with an air gun. However, the leakage ratio increased with time, measuring 7.3% after 5 years. Anti-bacterial test revealed that no bacteria were found during the test period. The largest change in the dimension occurred at the middle location of the element, although the change was less than 2% of the initial value.

Measurement of Defects on the Wall by use of the Inclination Angle of Laser Slit Beam and Position Tracking Algorithm of Camera (레이저 슬릿빔의 경사각과 카메라 자세 추정 알고리즘을 이용한 벽면 결함 측정)

  • 김영환;송상호;윤지섭;강이석
    • 제어로봇시스템학회:학술대회논문집
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    • 2000.10a
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    • pp.339-339
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    • 2000
  • In this parer, a method of measuring the size of defects on the wall and restructing the defect image of 3-dimension is developed based on the tracking algorithm of a camera position which uses the inclination angle of line slit beam for overcoming the difficulty of the corresponding problem identifying the image point in the both image. In the experiments, an algorithm for estimating the horizontal angle of CCD camera is presented and validated by applying it to the measurement of area and length under the variations of both the distance and the angle of CCD camera. And its performance is compared to that of the rotating and mapping method of image which has the Euclidian distance.

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