• Title/Summary/Keyword: Measuring instrument

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Solar Radiation Measurement and Data Quality Management (태양자원 측정 및 데이터 품질관리)

  • Jo, Dok-Ki;Yun, Chang-Yeol;Kim, Kwang-Deuk;Kang, Young-Heak
    • 한국신재생에너지학회:학술대회논문집
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    • 2010.11a
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    • pp.63.2-63.2
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    • 2010
  • Solar radiation data are used in several forms and for a variety of purposes. The most detailed information we have is beam and diffuse solar radiation on a horizontal surface, by hours, which is useful in simulations of solar processes. Daily data are more often available and monthly total solar radiation on horizontal surface can be used in some process design methods. However, as performance is generally not linear with solar radiation, the use of average may lead to serious errors if non-linearities ara not taken into account. It is also possible to reduce radiation data to more manageable forms by statistical methods. The control of the quality of most measurements is relegated to the control of the measuring instruments and measuring processes themselves. An accurate measurement will usually result from the use of a high-quality instrument that has been accurately calibrated and is properly used by a qualified individual.

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A Survey on the Current State and the Characteristics of Scoliosis in College Students

  • Jung, Hwa Shik
    • Journal of the Ergonomics Society of Korea
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    • v.18 no.3
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    • pp.13-26
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    • 1999
  • 126 male and 95 female Korean college students were examined for Scoliosis by using Moire type body observation apparatus. Scoliotic hump measuring instrument, and spinal cord side curvature condition measuring instrument. The prevalence rate of Scoliosis along with identifying its possible causal factors and characteristics were investigated. The results revealed that 5.56% of male and 8.42% of female students(male to female ratio 1:1.47) were suspected as having Scoliosis. There was a significant correlation between the students who have symptoms of Scoliosis and their physiological measurements(e.g., lower breathing capacity of the lungs). There were also close relationships between the suspected cases and their habits(e.g., poor sitting and sleeping posture). It is concluded that the Scoliosis in Korean college students should not be ignored.

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The Development of an Instrument for Measuring Scientific Attitudes of Elementary School children (국민학생의 과학적 태도 측정을 위한 도구 개발)

  • Chung, Wan-Ho;Hur, Myung;Yeun, Beong-Ho
    • Journal of The Korean Association For Science Education
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    • v.14 no.3
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    • pp.265-271
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    • 1994
  • The purpose of this survey was to develop the scale for measuring scientific attitudes. This instrument was contain 37 items of five-point Likert format. This survey is designed to measure scientific attitudes of elementary school 3-6 grade. The main results of this survey are as follows: (1) The internal consistency(reliability) was estimated using Cronbach ${\alpha}$ coefficient. The ${\alpha}$ coefficient was 0.91. (2) Male students exhibited more positive attitudes than females according to 2-Way ANOVA. (3) The interaction effect of sex and grade is not significant in level ${\alpha}=.05$. (4) The constructed scale was administered to 343 childrens in grade 3 to 6 of 8 elementary schools in Seoul and Kyeung-gi province.

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Ambient Vibration Measurement of Buildings Horizontal Vibration Using a Mobile Phone Application (휴대폰 앱을 이용한 건물 수평진동의 상시진동계측)

  • Moon, Sang-Hyouen;Yoon, Sung-Won
    • Journal of Korean Association for Spatial Structures
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    • v.15 no.3
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    • pp.77-83
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    • 2015
  • The cases of conducting the vibration measurement using the mobile phone with regard to the building's horizontal vibration are very rare in Korea and foreign countries. Therefore, this study analyzed the horizontal vibration nature of the building using the mobile phone targeting 5 tall buildings, and reviewed about the applicability of the mobile phone vibration measuring instrument through the comparison/verification with the data of the existing vibration measuring instrument. The peak of the measured time series waveform was measured clearly and it showed a similar value to the existing natural frequency.

Development of a Wavelet Based Optical Instrument Autofocusing algorithm (일차원 웨이브렛 변환을 이용한 광학기기의 자동 초점 조절에 관한 연구)

  • Park, Bong-Kil;Kim, Se-Hoon;Kim, Yoon-Soo;Park, Sang-Hui
    • Proceedings of the KIEE Conference
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    • 1997.11a
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    • pp.603-605
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    • 1997
  • A new algorithm using 1-dimensional wavelet transform for autofocusing of optical instrument has been developed. Previous studies based on the conventional frequency analysis have shown that as the lens-object distance approaches the optimum value, the high frequency energy in the corresponding image shows a consistent increase. However, as conventional frequency analysis techniques hide spatial distribution of each band energy, shape information in the original signal cannot be easily utilized. In this paper, a newly devised wavelet based focus measuring scheme is presented. Unlike other frequency domain analysis techniques that simply produce "frequency-only" spectra, wavelet analysis provides a "time-frequency" localized view of a given signal. As a result, both frequency band filtering and spatial distribution filtering can easily be realized. Depending on the proposed focus quality measuring algorithm, a fast and reliable automatic focus adjustment of optical devices could be implemented.

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A Design on neutron absorber and moderator for the content measurement of Asphalt (아스팔트 함량 측정을 위한 중성자 흡수체 및 감속재 설계)

  • Kim Ki-Joon
    • Journal of the Korea Computer Industry Society
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    • v.7 no.1
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    • pp.7-14
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    • 2006
  • In Korea, under the influence of the jurisdiction, usage of radioisotopes are limited. The limitation is $100[{\mu}Ci]$ or less. Therefore, in this study, basic data were designed, and the following data are needed in order to improve content measuring instrument which is suitable for radioisotopes limitation. Owing to the source and detector's properties, measuring instrument was designed geometrically, neutron and photon's particle transportation was analysed by using the MCNP code which is in Monte Carlo Method, also the location of source and detectors, geometrical structure of neutron absorber and moderator was designed.

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Development of Wireless Instrument for Measuring Cattle's Somatic Information for Stockbreeding Automatization(II) - Development of Single-Channel Wireless Instrument for Measuring Sphygmus - (축산자동화를 위한 가축의 생체정보 무선 계측장치 개발(II) - 단일채널 무선 맥박 계측장치 개발 -)

  • Lee, S.K.;Min, Y.B.;Kim, T.K.
    • Journal of Biosystems Engineering
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    • v.17 no.4
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    • pp.404-409
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    • 1992
  • It is important to measure the somatic informations for stockbreeding automatization. This study was carried out for the development of wireless measurement system of sphygmus in living animals. In meauring sphygmus counting with the single-channel telemety system, a LED-photo transistor sensor showed more sensitivity to the change of blood pressure than a piezo-electric sensor based pressure sensor. The LED-photo transistor sensor resulted ${\pm}1.29%$ of measurement error of sphygmus counting. In the process of transmitting and receiving the blood pressure signal for counting sphygmus, noises were mixed with, and the noises made the counting almost impossible. Auto-correlation analysis technique was applied to the signal data to extract the sphygmus information, and the technique was proved to be very effective.

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Magnetic Shielding Effectiveness Measurement of Magnetic Steel Sheets in ELF Range

  • Yeon, Kyo-Heum;Son, Derac;Park, Eon-Byeong;Lee, Jae-Young;Do, Kyung-Hwan;Park, Jae-Seg
    • Journal of Magnetics
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    • v.13 no.4
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    • pp.173-176
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    • 2008
  • In this study, a new kind of instrument for measuring the magnetic shielding effectiveness (MSE) was developed using a double yoke; one a magnetizing yoke and the other a sensing yoke. Using the developed instrument, the MSE could be measured for a steel sheet specimen in the ELF range, where the magnetic permeability contributes to the MSE at low frequencies and eddy currents contributes to the MSE high frequencies with < 0.1 dB reproducibility. The developed measuring method can be applied to quality control in a steel sheet company producing EMI/EMC shielding materials.

A Study on an experimental basis a use deodorize stink of food-waste in order to cooling dehumidification (냉각 제습에 의한 음식물 쓰레기 처리장치 악취제거에 관한 실험적 연구)

  • Park, I.S.;Kim, J.D.
    • Journal of Power System Engineering
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    • v.12 no.1
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    • pp.35-40
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    • 2008
  • This paper presents an effective cooling dehumidification method to remove odorous gas from food-wastes. The odorous gases, such as Styrene, Ammonia, Hydrogen sulfide and Acetaldehyde, are produced in environments where temperature is $50\sim80^{\circ}C$ and humidity is $40\sim70%$. Under such conditions, experiments are performed reiteratively using experiment equipments. The effect of the cooling dehumidification is measured via measuring instrument, and this research is focused on improving efficiency. The effect of cooling dehumidification using measuring instrument is validated. At $80^{\circ}C$, four type of gases that was mentioned previously showed generally better cooling efficiency with a good result for a component concentration. Among them, hydrogen sulfide gas demonstrated the highest reduction of 50%.

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Output performance of current transformer on over-current (직류분전류를 포함한 과전류에 대한 변류기의 출력특성)

  • Jung, Heung-Soo;La, Dae-Ryeol;Kim, Sun-Koo;Roh, Chang-Il;Kim, Won-Man;Lee, Dong-Jun
    • Proceedings of the KIEE Conference
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    • 2005.07b
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    • pp.951-953
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    • 2005
  • The current transformer is used for the insulation of measuring instrument, enlargement of measurement scope, standardization of measuring instrument, control of protective device. It's required various performance as the intention of service, site of establishment, insulation. especailly, current transformer has small ratio errors. if current transformer has large ratio error, it's caused a electricity failure. so in this paper, we examine the theory of current transformer, major factor of errors, output performance on over-current.

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