• 제목/요약/키워드: Measurement technology

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The Evaluation Tool and Process for Effective Education Outcomes Measurement and Analysis of Computer Education

  • Kim, Young-Tak;Sim, Gab-Sig
    • 한국컴퓨터정보학회논문지
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    • 제21권9호
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    • pp.149-156
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    • 2016
  • This paper is concerned with education courses operating practices for basic computer literacy training. In this study, we propose an example for students to effectively measure and evaluate the achievement of defined ability in the performance measurement and analysis, learning objectives and learning outcomes set in operation throughout the course. Through research and development use case presents the tools for teaching method and effective and objective measurement of the related subjects. And based on the results, we propose the possibility of utilizing NCS-based course operation and education certification. In this study, the measurement process is based on the association with the objective of the development and operation, and measurement tools, measuring tools for measuring learning outcomes associated with the curriculum design methods for the measurement and evaluation of the case of the operation of the course units of learning outcomes and the method proposed.

Utilization of Light Microscopy and FFT for MFA Measurement from Unstained Sections of Red Pine (Pinus Densiflora)

  • Kwon, Ohkyung;Lee, Mi-Rim;Eom, Chang-Deuk
    • Journal of the Korean Wood Science and Technology
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    • 제41권5호
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    • pp.399-405
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    • 2013
  • This study demonstrates the utilization of light microscopy and Fast Fourier Transform-Peak Finding (FPF) method for microfibril angle (MFA) measurement from unstained sections of red pine (Pinus densiflora). To obtain an image with optimal contrast and resolution for MFA measurement, effects of numerical aperture (NA) of condenser lens and color filters were investigated. About 60% of NA of the maximum condenser NA produced an image with optimal contrast, but a color filter with short wavelength range (DAPI) created images with improved resolution. Manual angle measurement and the FPF method were applied to the image with optimal contrast for MFA measurement. The experimental results from the FPF method were considered to be more repeatable and less subjective than those from the manual angle measurement.

공기열원 히트펌프의 에너지 효율 비율에 관한 실험적 연구 (An Experimental Study on the Energy Efficiency Ratio of Heat Pump for Air Source)

  • 정순영
    • 한국수소및신에너지학회논문집
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    • 제33권6호
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    • pp.838-844
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    • 2022
  • In this paper, an experimental study was conducted on the energy efficiency ratio of performance for air source heat pump. The energy efficiency ratio presents the operating efficiency of heat pump performance. In order to improve reliability in the energy efficiency ratio test of air source heat pump, the measurement uncertainty of the instrument was estimated. Measurement uncertainty refers to the uncertainty of a measurement, estimates the range in which the expected value of the measurement can be within a certain confidence level, and suggests a range in which the measured representative value is incorrect. The measurement uncertainty for the energy efficiency ratio test of air source heat pump was calculated and the measured results were presented.

듀얼 비콘의 거리측정을 활용한 스마트 유모차용 도난방지 기법 (Theft Prevention Technology for Smart Stroller using Distance Measurement of Dual Beacon)

  • 정명범
    • 인터넷정보학회논문지
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    • 제21권6호
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    • pp.71-79
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    • 2020
  • 본 논문에서 우리는 스마트 유모차를 위한 비콘과 스마트 기기 기반 도난 방지 기술을 제안한다. 스마트 유모차는 두 개의 블루투스 기기를 내장한다. 하나의 블루투스는 데이터 상호 교환을 위한 것이며, 또 다른 블루투스는 거리 측정을 위한 비콘으로 사용한다. 즉, 스마트 기기는 데이터 상호 교환 기능으로 근력 보조 레벨 설정, 유모차 수동 잠금과 유모차 정보 제공 등에 사용하며, 비콘 기능을 이용하여 스마트 기기와 유모차의 주기적인 거리를 측정하여 거리가 멀어지는 경우 도난 방지 기능이 동작하게 한다. 우리는 도난 방지 기능의 성능을 높이기 위해 향상된 비콘 거리 측정 기술을 이용한 거리 측정 알고리즘과 도난 방지 알고리즘을 적용하였다. 제안 방법의 효용성을 확인하기 위해 스마트 기기 애플리케이션을 개발하고 스마트 유모차를 제작하여 2가지 거리 측정 실험과 하나의 도난 방지 실험을 하였으며, 그 결과 91.3%의 도난 방지 정확성을 나타냈다. 따라서 제안한 도난 방지 기술은 스마트 유모차에 보다 유용한 기술이 될 것이다.

Characterization of the Stress-optic Properties of Ceramics by Terahertz Time-domain Spectroscopy

  • Zhi Qiang Wang;Wen Jia Ren;Gui Ying Zhang;Zhi Yong Wang
    • Current Optics and Photonics
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    • 제8권3호
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    • pp.225-229
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    • 2024
  • This paper introduces a rapid measurement technique for the stress-optic coefficient, using terahertz time-domain spectroscopy. First we propose a design combining a four-point bending device with a scanning stage to streamline the loading process. Then we detail the measurement principle and outline the signal-processing algorithm. The experiments are carried out on Al2O3, a representative ceramic material. The experimental data reveal that the refractive index of Al2O3 exhibits a linear decrease with increasing stress. This work supplies an efficient method for stress measurement rooted in the stress-optic effect.

초정밀 광학식 변위 측정을 위한 센서 구호 밀 신호 처리 시스템 (Sensor Structure and Signal Processing System for Precision Optical Displacement Measurement)

  • 오세백;김경찬;김수현;곽윤근
    • 한국정밀공학회지
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    • 제18권8호
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    • pp.40-47
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    • 2001
  • Optical measurement methods make it possible to detect object displacements with high resolution and noncontact measurements. Also, they are very robust against EMI noises and have long operation range. An optical triangulation sensor is one of widely used displacement measurement sensors for its sub-micron resolution, fast response, simple structure, and low cost. However. there are several errors caused by inclinations of a surface. speckle effects, power fluctuations of light sources, and noises of detectors. In this paper, in order to minimize error effects, we performed error analysis and proposed a new structure. Then, we setup a new modeling method and verify it through simulations and experiments. Based on the new model. we propose a new sensor structure and establish design criteria. Finally, we design a signal processing system to overcome a resolution-limited problem of light detectors. The resolution of the proposed system is 0.2${\mu}{\textrm}{m}$ in 5mm operating range.

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Effect of Wall Groove Characteristics on Yield Stress Measurement of Magnetorheological Fluid

  • Tian, Zuzhi;Guo, Chuwen;Chen, Fei;Wu, Xiangfan
    • Journal of Magnetics
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    • 제22권2호
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    • pp.281-285
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    • 2017
  • To suppress the wall slip effect and improve the yield stress measurement precision of magnetorheological fluid, measurement disks with different grooves are first manufactured. Then, the influence of groove characteristics on the yield stress of magnetorheological fluid is investigated by the method of experiments. Finally, the optimization wall grooves of measurement disks are obtained, and the yield stress of a self-prepared magnetorheological fluid is measured. Results indicate that the groove type and groove width have a slight influence on the shear yield stress, whereas the measured yield stress increases with enhanced groove density, and the optimized groove depth is 0.3 mm. The measured shear yield stress of self-prepared MR fluid can be improved by 18 % according to the optimized grooved disks, and the maximum yield stress can reach up to 65 kPa as the magnetic flux density is 0.5 T.

무선 센서네트워크 기반 차량속도 측정 시스템 (Vehicle Speed Measurement System based on Wireless Sensor Network)

  • 유성은;김태홍;박태수;김대영;신창섭;성경복
    • 대한임베디드공학회논문지
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    • 제3권1호
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    • pp.42-48
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    • 2008
  • The architecture of WSN based Vehicle Speed Measurement System is presented in this paper from Telematics Sensor Network(TSN) to Management System. To verify the feasibility of the system, we implemented the vehicle speed measurement system and evaluated the accuracy of velocity measured by the system in our testbed, an old highway located near Kyungbu highway. The system performed over 95% of accuracy at 80kmph from the measurement. In addition, the battery life time of the sensor node was evaluated by simulation analysis with real measured current consumption profiles. Assuming the maximum average daily traffic in 2005, the battery life time is expected to be over 1.6 year from the simulation result.

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UV-Vis 분광분석에 의한 전기변압기 내 절연지 열화도 측정 (Application of UV-Vis Spectroscopic Analysis for Transformer Insulating Paper Degradation)

  • 공호성;한흥구
    • Tribology and Lubricants
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    • 제35권3호
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    • pp.151-157
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    • 2019
  • Insulated oil degradation produces charged by-products, such as acids and hydro-peroxides, which tend to reduce the insulating properties of the oil. In this study, UV-vis spectroscopy measurement technology is developed and experimentally compared with other measurement methods, such as the titration method and IR spectroscopy, to validate its ability to monitor the degradation of electrical insulating paper. The degradation characteristics of the insulating paper are appropriately represented through various types of measurement methods, such as the Tan (delta) method, $CO_2$ gas production measurement, the titration method, and IR spectroscopy. The results are demonstrated to be well comparable to a change in the fluorescence emission ratio (FER), which is defined as the shift in fluorescence intensity in the measured wavelength range, and also to the chromatic ratio, which is defined as a color shift to longer wavelength ranges. The results also show that, by using UV-vis spectroscopy, it is possible to detect the degradation of the insulating paper. This study suggests that UV-vis spectroscopy can be applied as an alternative to high-performance liquid chromatography, which is the internationally recognized measurement technology for cellulose paper degradation. The FER detector is also verified to be useful as an effective condition-monitoring device for power transformers.