• Title/Summary/Keyword: Measuring instrument

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A New Magnatic Modulation for Improving Sensitivity of DC Current Sensor (DC 전류검출기의 감도 개선을 위한 새로운 자기변조)

  • Kim, Han-Sung;Lee, Hwan
    • The Transactions of the Korean Institute of Electrical Engineers
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    • v.43 no.2
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    • pp.268-277
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    • 1994
  • Current sensor using Hall device is an instrument of detecting a current by Hall effect. The existing current sensor is ordinarily worked by concentrating electromagnetism produced around the conducting wire turned iron core. The tiny curren, however, could not be accurately detected by the instrument owing to influence of residual magnetism exisisting in iron core, and the result of detecting is also somewhat on the large side. kAccordingly, We fabricated a new type of instrument minimizing the influence of residual magnetism existing in iron core and detected the tiny DC current accurately by taking advantage of magnetic modulation. The range of measuring DC current is 0[mA]-100[mA] and the maxiumm Linerity tolleance by the result of detecting current, can be reduced less than 3 percent.

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MICROTHERMAL INSTRUMENT FOR MEASURING SURFACE LAYER SEEING

  • Li, Xue-Bao;Zheng, Yan-Fang;Deng, Lin Hua;Xu, Guang
    • Journal of The Korean Astronomical Society
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    • v.45 no.1
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    • pp.19-24
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    • 2012
  • Microthermal fluctuations are introduced by atmospheric turbulence very near the ground. In order to detect microthermal fluctuations at Fuxian Solar Observatory (FSO), a microthermal instrument has been developed. The microthermal instrument consists of a microthermal sensor, which is based on a Wheatstone bridge circuit and uses fine tungsten filaments as resistance temperature detectors, an associated signal processing unit, and a data collection, & communication subsystem. In this paper, after a brief introduction to surface layer seeing, we discuss the instrumentation behind the microthermal detector we have developed and then present the results obtained. The results of the evaluation indicate that the effect of the turbulent surface boundary layer to astronomical seeing would become sufficiently small when installing a telescope at a height of 16m or higher from the ground at FSO.

A Study on the Development of a Clothing Design Evaluation Instrument (의복디자인의 평가도구 개발을 위한 연구 -실루엣 평가를 중심으로-)

  • 이경희
    • Journal of the Korean Home Economics Association
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    • v.29 no.1
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    • pp.37-49
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    • 1991
  • The purpose of this study was to investigate the visual effects of clothing design. The specific objectives were: 1) to develop a clothing design evaluation instrument using semantic differential scales for the purpose of measuring visual responses with clothing design: 2) to identify the factor structure of the clothing design evaluation instrument: 3) to test the differences of perception to the clothing design depending on sex and knowledge about clothing design. The major findings were: 1. 37 pairs of descriptors of clothing form were found to include five factor dimensions (total variance:62.1%). Five major factors were found: attractiveness, practicability, elegance, comfort, hardness and softness. 2. for the visual evaluation of silhouettes, there were significant differences. H-line was explained by the simple image. A-line was explained by the comfortable image. V-line was explained by the mature and refined image. X-line was explained by the attractive and femine image and evaluated positively. 3. For the visual evaluation of observers, there were partly significant differences depending on sex and knowledge about clothing design in the observers' responses. But there were greater differences depending on sex than knowledge about clothing design in the observers' responses.

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Psychometric properties of an instrument 3: convergent, discriminant, known-groups, and criterion validity (측정도구의 심리계량적 속성 3: 수렴, 판별, 집합 및 준거타당도)

  • Lee, Eun-Hyun
    • Women's Health Nursing
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    • v.27 no.3
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    • pp.176-179
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    • 2021
  • Before evaluating convergent, discriminant, and known-groups validity, it is suggested to design an instrument that reflects hypothetical relationships or differences with other comparator instruments or groups. For criterion validity, a gold-standard instrument measuring the same construct should be carefully selected.

Development of Force Measuring System using Three-axis Force Sensor for Measuring Two-finger Force (3축 힘센서를 이용한 두 손가락 힘측정장치 개발)

  • Kim, Hyeon-Min;Yoon, Jong-Won;Shin, Hee-Suk;Kim, Gab-Soon
    • Journal of Institute of Control, Robotics and Systems
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    • v.16 no.9
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    • pp.876-882
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    • 2010
  • Stroke patients can't use their hands because of the paralysis their fingers. Their fingers are recovered by rehabilitating training, and the rehabilitating extent can be judged by measuring the pressing force to be contacted with two fingers (thumb and first finger, thumb and middle finger, thumb and ring finger, thumb and little finger). But, at present, the grasping finger force of two-finger can't be accurately measured, because there is not a proper finger-force measuring system. Therefore, doctors can't correctly judge the rehabilitating extent. So, the finger-force measuring system which can measure the grasping force of two-finger must be developed. In this paper, the finger-force measuring system with a three-axis force sensor which can measure the pressing force was developed. The three-axis force sensor was designed and fabricated, and the force measuring device was designed and manufactured using DSP (Digital Signal Processing). Also, the grasping force test of men was performed using the developed finger-force measuring system, it was confirmed that the grasping forces of men were different according to grasping methods.

Development of Ground Impedance Measuring Instrument for Lightning Protection System (뇌보호 설비를 위한 접지임피던스 측정기 개발)

  • Lee, Tae-Hyung;Cha, Sung-Chul;Earn, Ju-Hang
    • Proceedings of the KIEE Conference
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    • 2006.10a
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    • pp.194-195
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    • 2006
  • This study evaluated the impedance characteristics of earth termination system and developed a variable frequency-typed inverter (measuring tool) for the utilization in ground design for lightning protection. The variable-frequency-typed inverter were composed of rectification part, voltage adjuster, IGBT controller and measuring part. Meanwhile, the square wave signal of variable frequency converted its frequency up to lightning surge band by using an IGBT after rectifying an alternating current (AC). It conducted performance evaluation of ground impedance of actual earth termination system by using the developed measuring tool for ground impedance and confirmed that such impedance-oriented performance evaluation was effective in the design of lightning protection.

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The Development of the Environmental Literacy Instrument for the Elementary School Students (초등학생 환경 소양 측정 도구의 개발)

  • Jung, Hyun-Hee;Seo, Woo-Seok
    • Hwankyungkyoyuk
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    • v.21 no.4
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    • pp.79-93
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    • 2008
  • The purpose of this study was to develop an instrument for measuring elementary school students' environmental literacy. The process of instrument development was four phases. The first two phases involved defining the domain of the construct, writing an initial pool of 55 items, and reviewing the items for revision and deletion. These steps were taken to provide the evidence of content-related validity, and to reduce a number of items. The third phase was, through item analysis, to determine the most appropriate items for the environmental literacy for the elementary school students. For the forth phases, the fifth and sixth students in elementary school participated in this survey. To examine the reliability and validity of environmental literacy for the elementary school students, internal consistency estimate, and factor analysis were used. The results of this study were summarized as follows; Firstly, thorough factor analysis, we developed Environmental Literacy Instrument for the elementary school students, consisted of total 41 items (knowledge 8 items, emotion 11 items, skill 10 items, and behavior 13 items); Secondly, Cronbach's alpha was .783 for knowledge, .832 for emotion, .866 for skill and 8.61 for behavior.

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The Development of Mathematics Teaching Efficacy Instrument (수학 교수 효능감 측정 도구 개발 연구)

  • Kang, Moonbong;Kim, Jeongha
    • Journal of Elementary Mathematics Education in Korea
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    • v.18 no.3
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    • pp.519-537
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    • 2014
  • Teacher efficacy influences teacher's own behaviors in class and students outcomes such as achievement, motivation and their own self-efficacy. In recent years, self efficacy and teacher efficacy are becoming more popular in many educational aspects. Teacher efficacy depends on him/her and each tasks and goals. Therefore, we need special instrument for measuring mathematics teacher efficacy. On this study, we derived educationally meaningful factors on mathematics teacher efficacy from previous literature. We developed Mathematics Teaching Efficacy Instrument(MTEI) consisted of 30 items with 6-point Likert scale. The six factors are as follows; mathematics teaching efficacy expectancy, mathematics teaching outcome expectancy, mathematics teaching content knowledge, teacher belief on their own students, the past mathematics learning experience for teacher own, influence from social-cultural environment.

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A Study on the Pulmonary Functional Characteristics of Amateur Wind Instrument Players and Choir Members

  • Baek, Jeong Yun;Kim, Joong Hwi
    • The Journal of Korean Physical Therapy
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    • v.34 no.5
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    • pp.248-254
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    • 2022
  • Purpose: This study was undertaken to identify the effect of amateur wind musical performance and choir activity on pulmonary function, and to determine the usefulness as a respiration training program by measuring the pulmonary functions of subjects. Methods: A total of 90 subjects (wind instrument players group=30, choir members group=30, control group=30) participated in the experiment. Pulmonary function test (FVC, FEV1, FEV1/FVC ratio, MVV, SVC, PEF, FEF 25-75%, IRV, ERV) was conducted using a spirometer (CardioTouch 3000S, Bionet, Seoul, Republic of Korea). Each factor was measured 3 times to meet the American Thoracic Society criteria, and the highest value was used in the analysis. Results: Comparing pulmonary function between the amateur wind instrument players (WP), amateur choir members (CH), and control (CG) groups revealed significant differences in FEV1, FVC, FEV1/FVC, and ERV (p<0.05). Highest values were obtained in the WP group. Significant differences were obtained for various factors in the multiple regression analysis of practice year (PY), practice time per week (PTPW), and exercise time per week (ETPW): FEV1 and FVC in PY, FEV1/FVC in PTPW, and FEV1/FVC, MVV, PEF, and FEF (25-75%) in ETPW. Conclusion: Amateur wind instrument performance effectively improves lung function and is useful as a breathing training program for preventing debilitation and improving respiratory function.

The Technology for Reduction of Color Difference to Exhaustion Dyeing (흡진염색에서의 색상차이 감소 기술)

  • 김기정
    • Journal of the Korean Professional Engineers Association
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    • v.33 no.5
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    • pp.45-48
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    • 2000
  • DyeMax-L system(a real-time dyeing measuring system) which can do on line monitoring of dyeing process and measurement of the exhaustion of individual dye in mixtured dyes were developed By using the instrument, the compatability of mixture dyes and changes of exhaustion behavior of each dye with the variation of dyeing auxiliaries and dyeing conditions to get factors for control of dyeing

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