• Journal of Korea Technology Innovation Society
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• v.4 no.1
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• pp.110-126
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• 2001

In this study, we survey the demand of precision measurement technology including instrument and technical manpower in Korean industry and institution. Also this study is purposed to improve the metrological technology by suggesting the solution of technical problems.

• Journal of Biosystems Engineering
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• v.35 no.6
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• pp.443-449
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• 2010

A machine vision-based instrument to measure a droplet size spectrum of a spray nozzle was developed and tested to evaluate its accuracy on measuring spray droplet sizes and classifying nozzle sizes. The instrument consisted of a machine vision, light emitting diode (LED) illumination and a desktop computer. The illumination and machine vision were controlled by the computer through a C++ program. The program controlled the machine vision to capture droplet images under controlled illumination, and processed the droplet images to characterize the droplet size distribution of a spray nozzle. An image processing algorithm was developed to improve the accuracy of the system by eliminating random noise and out-of-focus droplets in droplet images while measuring droplet sizes. The instrument measured sizes of the three different balls (254.0, 497.8 and $793.8\;{\mu}m$) and the measurement ranges were $241.2-273.6\;{\mu}m$, $492.9-529.6\;{\mu}m$ and $800.8-824.1\;{\mu}m$ for 254.0-, 497.84- and $793.75-\;{\mu}m$ balls, respectively. Error of the measured droplet mean was less than 3.0 %. Droplet statistics, $D_{V0.1}$, $D_{V0.5}$ and $D_{V0.9}$, of a reference nozzle set were measured, and droplet size spectra of five spray nozzles covering from very fine to extremely coarse were measured to classify spray nozzle sizes. Ninety percent of the classification results of the instrument agreed with manufacturer's classification. A comparison study was carried out between developed and commercial instruments, and measurement results of the developed instrument were within 20 % of commercial instrument results.

• Journal of the Korean Society for Precision Engineering
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• v.27 no.4
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• pp.33-39
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• 2010

Manufacturing accuracy of a precision instrument was essential to stability and efficiency of the product. Accordingly, geometrically accuracy management of precision instrument was very becoming the technique in order to design and manufacturing for machine. In this study, Measuring System is developed for extra long roller using non-contact sensor. Futhermore, It's studied by Geometric Tolerance. Exact roundness is obtained to Least Squares method from the reference circle of measured data. Measuring System is analyzed point of measurement and straightness of extra long roller is evaluated by FEM.

• IEMEK Journal of Embedded Systems and Applications
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• v.9 no.4
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• pp.219-227
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• 2014

Natural disasters such as a ground collapse and a landslide have broken out due to the climate change of the Korea and the reckless expansion of cities and roads. The climate changes and the reckless urbanization have made the ground weak. Thus, it is important to keep a close eye on the highly weakened landslide and to prevent its natural disasters. In order to prevent these disasters, this paper presents a system of recognizing the road slide condition by measuring the displacements using laser scanner instrument. The previous system of monitoring the road slide has some problems as inaccurate recognition due to using only images from a camera, or expensive system such as artificial satellites and aircraft systems. To solve this problem, our proposed system uses the 3D range data from the laser scanner for measuring the accurate displacement of the road slide and optical flows from the Lucas-Kanade algorithm for recognizing the road slide in the image.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.59 no.4
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• pp.423-427
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• 2010

Portable sheet resistance-measuring instrument using the dual-configuration Four-Point Probe method is developed for the purpose of precisely measuring the sheet resistance of conducting thin films. While single-configuration Four-Point Probe method has disadvantages of applying sample size, shape and thickness corrections for a probe spacing, the developed instrument has advantages of no such corrections, little edge effects and measuring simply and accurately the sheet resistance between $0.2\Omega/sq$ and $2k\Omega/sq$.

• Transactions of the Korean Society of Mechanical Engineers
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• v.13 no.5
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• pp.862-874
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• 1989

A phase evil method and spectrum analysis were instrument error which is originated from measurement system and the form error of standard specimens. An instrument with a rotating table supported by an air bearing is calibrated using standard specimens. The phase of standard specimens was measured 12 times on the rotating table with rotating 30 in turn and its measurement magnification was set by 100000 times. As a result of data analysis of all the observations, read out at each of 144 orientations(per 2.5) from recorded datafiles, the error of the performance of the instrument and those of the standard specimens are evaluated and a systematic deviation of the instrument is determined. In the particular instrument used in the present experiment, the deviation of the instrument is determined with the accuracy of 15nm and those of standard specimens with the accuracy of 23, 13 n, respectively. The reproducibility of the instrument is investigated, too. If the instrument is calibrated by using the above standard specimens, then the accuracy of the measurement of roundness error can be improved to about 15nm.

• Proceedings of the KSR Conference
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• 2001.10a
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• pp.156-162
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• 2001

Current collection performance on-line tests for a Korean High Speed Train being developed in G7 project is scheduled to start in June, 2002. In this paper, preparatory efforts for measuring contact forces which is regarded as one of major measuring items in the test are introduced. Specifically speaking, review of frequencies related with contact force fluctuations, brief of contact force measuring algorithm, review of measuring instrument specifications and development of a data acquisition program are presented.

• Asian Oncology Nursing
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• v.1 no.1
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• pp.18-31
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• 2001

This Research was designed to develop an instrument that can be used for measuring and analysing the degree of the quality of life of the Allogenic bone marrow transplantation survivors and to provide basic data to help them attain a better quality of life. The subjects of this study were a total of 101 people who were undergone Allogenic bone marrow transplantation and were over 100 days after transplantation. Data were collected during the period from September 3 to December 2. 2000. In Developing this instrument, the researcher established a conceptual framework based on the result of previous research, interview of patients and medical staff and researcher's experience. The scale for this instrument consisted of 51 items. Responses were obtained from the respondents through a self reporting method and each item had a possible score of 5. The collected data were analyzed using the SPSS program. The reliability of the scale was tested by Cronbach‘s alpha. For the examination of the component factors of the measuring instruments, factor analysis method was used. Examination of the difference in the quality of life as related to demographic variables was done using t-test, analysis of variance(ANOVA). For the examination of the major variables influencing the quality of life, Pearson's Correlations was used. The results were as follows: (1) The reliability of the instrument was 0.90 (Cronbach's alpha) (2) The validity of the instrument was tested by factor analysis. The result of the factor analysis of the 51 items is making up the instruments were classified into the following factor; emotional state, Interpersonal problem, physical problem, spiritual state, social problem, decrease of physical energy, physical problem-eye, physical problem-skin and mucosa, health awareness, elimination problem, worry about health, financial problem, sexual problem. (3) Demographic variables related to quality of life is the time after transplantation. GVHD experience, lose of job. Age at the transplantation, diagnosis, type of the transplantation, marital status, monthly income, educational background, sex, religion are not related to the quality of life.

• Journal of Science Education
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• v.43 no.2
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• pp.258-269
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• 2019

This study developed an instrument for measuring STEAM education effectiveness focused on key competencies of STEAM. This study performed literature reviews on the prior studies associated with the STEAM education and completed a pilot instrument through reflective reviews by external experts. A pilot study was administered to a total of 408 students and finalized by statistical analyses such as reliability check and exploratory factor analysis. The factors of the final instrument were identified as convergence (seven items), creativity (eleven items), challenge (five items), and care (nine items). The Cronbach' ${\alpha}$ for each construct ranged from .849 to .929 turned out to be reliable. This instrument can be utilized for measuring the effectiveness of the STEAM education on students' key competencies.

• Journal of The Korean Association For Science Education
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• v.28 no.2
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• pp.139-149
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• 2008

The purpose of this study is to develop a valid and reliable instrument for measuring scientific problem-finding ability for the scientifically-gifted student. On the basis of an operational definition of scientific problem-finding ability, this instrument consists of five sections(appropriateness, flexibility, originality, elaboration, and valuation) which are designed for measuring the ability of the scientifically-gifted. This instrument was checked the validity of content and evaluation criteria by the five experienced specialists in science education, and then was administered to 38 students of science high school. Because the validity of content and evaluation criteria, construct validity, inter-rater reliability, item difficulty, and item discrimination are suitable for the criteria of good test, this developed instrument in this study is considered valid and reliable.