• IEMEK Journal of Embedded Systems and Applications
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• 제11권5호
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• pp.299-304
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• 2016

As public interest in air quality and environment problem is increasing, many researches are being carried out the gas measurement system. Especially, Non-dispersive infrared (NDIR) measurements using Beer-Lambert gas sensing principle with very high selectivity and long life time are noted for reliable method. It is possible to detect various gases such as carbon dioxide (CO2), carbon monoxide (CO), and nitrogen dioxide (NO2), but many researches are mostly concentrated on CO2 sensor. The multi-gas measuring instrument is high price and unwieldy, therefore it is not suitable for wide area required numerous instrument. So we study the NDIR multi-gas measurement system for air quality based on wireless sensor network, and experiment the realized measurement system.

• Progress in Superconductivity and Cryogenics
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• 제14권2호
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• pp.32-35
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• 2012

The objective of the present work is to develop a precise instrument for measuring the thermal property of insulating material over a temperature range from 30 K to near room temperature by utilizing a cryocooler. The instrument consists of two thermal links, a test sample, heat sink, heat source and vacuum vessel. The cold head of the cryocooler as a heat sink is thermally anchored to the thermal link and used to bring the apparatus to a desired temperature in a vacuum chamber. An electric heater as a heat source is placed in the middle of test sample for generating uniform heat flux. The entire apparatus is covered by thermal shields and wrapped in multi-layer insulation to minimize thermal radiation in a vacuum chamber. For a supplied heat flux the temperature distribution in the insulating material is measured in steady and transient state. The thermal conductivity of insulating material is measured from temperature difference for a given heat flux. In addition, the specific heat of insulating material is obtained by solving one-dimensional heat diffusion equation.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 한국공작기계학회 2004년도 추계학술대회 논문집
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• pp.114-121
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• 2004

The sensor and measuring instrument that are used for the infrastructure is discussed the reliability problem from the various environment factors. In the domestic infrastructure, the low reliability products are produced, because of lack of the pertinent test methods and equipments. To improve the practical use and accuracy of the sensor, it raises the measurement reliability about the sensor and measurement instrument. In this study, the variance of the displacement value according to temperature was investigated using the LVDT for the infrastructure. The experimental results showed that a sensor is affected by environment factor such as temperature.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 한국공작기계학회 2004년도 추계학술대회 논문집
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• pp.352-357
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• 2004

The high speed machining center(HMC) has been widely applied to manufacture a die and machine elements product in industrial field. Because the evaluation for HMC is not sufficiently performed, ineffective machining is occasionally conducted in machining industry. In this study, the dynamic characteristics of newly developed machining center is evaluated under running condition and the machinability is investigated experimentally. Also, the in-process measuring instrument which can measure the tool wear on the machine were developed by using the CCD and exclusive jig and calibration instrument for tool wear measurement.

• Proceedings of the Korean Society of Marine Engineers Conference
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• 한국마린엔지니어링학회 2012년도 전기공동학술대회 논문집
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• pp.129-129
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• 2012

Pumps are used widely in industry, the commercial sector and ships. A poorly selected pump or a pump that does not run at optimum design duty point is a classic symbol of wasted energy and money. It, therefore, becomes important to evaluate the efficiency of these pumps. This paper analyzes traditional technique and instrument to measure some parameters needed to calculate a pump efficiency. The pump efficiency measuring instrument (PEMI) was made and tested on real pump systems. It has been giver the accurate results compared with performance curve given by pump maker.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 한국전기전자재료학회 2003년도 춘계학술대회 논문집 기술교육전문연구회
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• pp.154-158
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• 2003

In this study, to measure the density of compaction, it is designed to use the 5 gamma-ray detectors. The developed instrument consists of measuring circuits for gamma-rays and thermal neutrons, a high voltage supply unit, stable circuit unit, count circuit unit and a microprocessor. To read count pulse from gamma-ray detectors are very accurate and it can be count to data calibration excluded count of ripple.

• Journal of the Semiconductor & Display Technology
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• 제3권1호
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• pp.31-34
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• 2004

We develop Mueller-matrix spectroscopic ellipsometry based on dual compensator configuration. This technique is very powerful for measuring surface anisotropy in nano-scale, especially when materials show depolarization. Dual-rotating compensator configuration is adopted with the rotational ratio of 5:3 originally developed by Collins et al[1]. The instrument can provide 250-point spectra over the wavelength range from 230 nm to 820 nm in one irradiance waveform with minimum acquisition time of Tc=10 s. In this work, the results obtained in transmission modes are presented for the initial attempt. We present calibration procedures to diagnose the system from the utilized data collected in transmission mode without sample. We expect that the instrument will have important applications in thin films and surfaces that have anisotropy and inhomogeneity.

• Proceedings of the Korea Society for Industrial Systems Conference
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• 한국산업정보학회 2001년도 춘계학술대회논문집:21세기 신지식정보의 창출
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• pp.114-128
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• 2001

정보화시대를 맞이하면서 컴퓨터와 통신의 결합체인 정보통신의 획기적인 발전에 의해 방대한 데이터의 신속·정확한 처리가 가능하게 되었으며, 이를 바탕으로 다양한 소비자의 요구에 효율적으로 대웅할 수 있게 되었다. 즉, 이러한 정보화의 급속한 발전과 더불어 개인의 다양한 사생활 영역으로부터의 개인정보들이 좀더 용이하게 축적되고 이용될 수 있게 되었다. 반면 이러한 현상은 개인정보의 무분별한 수집, 유통 및 오·남용을 유발할 수 있다는 측면에서 그 심각성이 더한다고 할 수 있다. 따라서 본 연구에서는 이러한 급진적 변화양상 속에서 개인의 정보를 취급하는 많은 기업 및 기관의 태도에 대해 개인이 지닌 의식을 조사하여 이를 토대로 실증적 Instrument를 제시하고자 하며, 이를 바탕으로 개인정보를 필요로 하는 관계기업들 즉, 전자상거래나 온라인에서의 마케터들에게 개인정보에 대한 소비자 의식을 파악할 수 있게 하여 앞으로 이에 효율적으로 대처할 수 있는 지침으로서의 역할을 제공하고자 한다.

• Journal of Biomedical Engineering Research
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• 제10권1호
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• pp.25-32
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• 1989

In this study, Rheoencephalography( REG ) was designed and constructed. Using the cons- tructed instrument cerebral blood flow(CBF) of left and right brain, CBF change by posture, and reproducibility were studied. Followings are important results. Relative CBF could be measured noninvasively and continuously. Since reproducibility of the constructed REG was found to be quite high (4%), the accuracy of the instrument itself was proved. REG can be easily applied for testing the effect of drugs for the patients with cerebral vessel diseases since it is quite sensitive to the relative changes of CBF. Various cerebral diseases can be diagnosed by analyzing the REG waveforms. The area of restricted cerebral blood vessels can be located by arranging the electrode configuration. Comparative studies with the standard techinques of measuring CBF are needed to verify the accuracy of REG. Further studies on optimal electrode configuration and various artifacts are also necessary.

• Proceedings of the Korean Society Of Semiconductor Equipment Technology
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• 한국반도체및디스플레이장비학회 2003년도 추계학술대회 발표 논문집
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• pp.12-17
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• 2003

We develop Mueller-matrix spectroscopic ellipsometry based on dual compensator configuration. This technique is very powerful for measuring surface anisotropy in nano-scale, especially when materials show depolarization. Dual-rotating compensator configuration is adopted with the rotational ratio of 5:3 originally developed by Collins et al [1]. The instrument can provide 250-point spectra over the wavelength range from 230 nm to 820 nm in one irradiance waveform with minimum acquisition time of $Tc{\approx}10 s$. In this work, the results obtained in transmission modes are presented for the initial attempt. We present calibration procedures to diagnose the system from the utilize data collected in transmission mode without sample. We expect that the instrument will have important applications in thin films and surfaces that have anisotropy and inhomogeneity.