• 유체기계공업학회:학술대회논문집
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• 유체기계공업학회 2001년도 유체기계 연구개발 발표회 논문집
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• pp.433-438
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• 2001

Noise is one of the major environmental problems in human life. To reduce the noise emitted from the control valve it is necessary to develop the measurement method, measurement system, analysis method applicable to the field. In this study IEC and ISO standards were investigated and measurement method for the valve noise was proposed. Noise from the valve was measured in the reverberation room and sound power level was calculated. The sound power level increased as the flow rate and pressure difference increased. The noise characteristics are useful to predict valve noise for given conditions, to compare the performance of different valves and to develope low-noise valves.

• 한국콘텐츠학회:학술대회논문집
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• 한국콘텐츠학회 2005년도 추계 종합학술대회 논문집
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• pp.611-615
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• 2005

본 논문은 향후에 구축될 BcN망을 통해 제공될 멀티미디어 서비스를 위한 QoS를 보장하기 위해 서비스를 분류하고 풀질기준과 측정방법을 분석한다. 현재의 서비스 및 향후 BcN에서 제공될 서비스를 분류하였고, 종단간 품질기준을 살펴보고, 종단간 품질측정을 위한 측정방안으로서 호성공률, 패킷손실율, 단방향지연, 지터, R-값 등의 측정방법을 소개하였다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1999년도 춘계학술대회 논문집
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• pp.426-429
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• 1999

In this paper, we have provided the measurement technique of the grounding mesh resistance by field measurements. The standard of measurement is specified in the IEEE Std 81.2-1991 and JEAC 5001-1988, which is the the fall-of-potential method by test-current injection, but this method is difficult to apply at field, where is small around a electric power substation of domestic. For the convenient measurement method, space of assistant probe and quantity of test-current injection are changed step for step. As the result, ' the proposed measurement technique of grounding mesh resistance is that the space of current and potential probes must be fixed at 150rn from a grounding mesh, the test-current injection has to keep 5A or more.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2004년도 추계학술대회논문집
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• pp.503-507
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• 2004

This paper is concerned with the measurement of low-frequency vibrations of structures using the image processing method. To measure the vibrations visually, the measurement system consists of a camera, an image grabber board, and a computer. The specific target installed on the structure is used to calculate the vibration of structure. The captured image is then converted into a pixel-based data and then analyzed numerically. The limitation of the system depends on the image capturing speed and the size of image. In this paper, we discuss the methodology for the vibration measurement using the image processing method. The method enables us to measure the displacement directly without any contact. The resolution of the vibration measurement can be refined but limited to the sub centimeter displacement.

• 한국군사과학기술학회지
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• 제22권2호
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• pp.233-240
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• 2019

High-altitude ElectroMagnetic Pulse(HEMP) is a high-power electromagnetic pulse caused by nuclear explosions at altitudes above 30 km. This pulse can cause serious damage to the electrical/electronic device. Therefore, there are a lot of studies on the effects of HEMP in the literature. When conducting studies on the effects of HEMP, it is essential to measure the simulated HEMP. Depending on the need for measurement, this paper focuses on the HEMP measurement method. This paper proposes a measurement method using frequency domain compensation to extract the correct waveform and solves the offset problem more efficiently than the conventional methods. The proposed method is verified by experiment using HEMP simulator and measurement system in ADD.

• 감성과학
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• 제13권1호
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• pp.111-120
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• 2010

제품 사용자의 감성 측정 연구에 있어서 제품을 처음 접하는 순간에 무의식적으로 발생하는 초기 감성의 측정은 매우 중요하다. 일반적으로 사용자의 감성은 사용자의 주관적인 평가를 토대로 하는 심리적 측정방법과 생리신호를 이용하는 생리적 측정방법, 그리고 행위적인 반응을 측정하는 행위적 측정방법이 있다. 하지만 각 측정방법들이 초기 감성 측정에 활용될 경우 여러 가지 한계점들이 발생하게 된다. 따라서 본 연구에서는 사용자가 제품을 실제 접하는 환경에서의 초기 감성을 측정할 수 있는 방법을 제안하였다. 먼저 사용자의 초기 감성을 보다 객관적이고 체계적으로 측정하기 위한 초기 감성 측정 프레임워크를 제시하였고, 이에 부합하는 감성 측정 방법들을 활용하여 사용자의 초기 감성을 보다 정확하게 측정할 수 있는 초기 감성 측정 시스템(IEMS)을 제안하였다. 시선 추적 및 동공 크기 변화를 측정하기 위해 모바일 시선 추적 장비를 활용하였고, 행동 관찰을 위한 관찰 카메라와 음성 녹음을 위한 휴대용 음성 녹음기를 결합하여 생리적, 행위적 감성 반응이 측정 가능한 초기 감성 측정 시스템을 제안하였다. 본 연구를 통해 실제 제품을 접하는 환경에서 사용자의 초기 감성을 보다 정확하고 객관적으로 측정할 수 있을 것으로 판단된다.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2011년도 제40회 동계학술대회 초록집
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• pp.30-30
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• 2011

The wave-cutoff tool is a new diagnostic method to measure electron density and electron temperature. Most of the plasma diagnostic tools have the disadvantage that their application to processing plasma where toxic and reactive gases are used gives rise to many problems such as contamination, perturbation, precision of measurement, and so on. We can minimize these problems by using the wave-cutoff method. Here, we will present the results obtained through the development of the wave-cutoff diagnostic method. The frequency spectrum characteristics of the wave-cutoff probe will be obtained experimentally and analyzed through the microwave field simulation by using the CST-MW studio simulator. The plasma parameters are measured with the wave-cutoff method in various discharge conditions and its results will be compared with the results of Langmuir probe. Another disadvantage is that other diagnostic methods spend a long time (~ a few seconds) to measure plasma parameters. In this presentation, a fast measurement method will be also introduced. The wave-cutoff probe system consists of two antennas and a network analyzer. The network analyzer provides the transmission spectrum and the reflection spectrum by frequency sweeping. The plasma parameters such as electron density and electron temperature are obtained through these spectra. The frequency sweeping time, the time resolution of the wave-cutoff method, is about 1 second. A short pulse with a broad band spectrum of a few GHz is used with an oscilloscope to acquire the spectra data in a short time. The data acquisition time can be reduced with this method. Here, the plasma parameter measurement methods, Langmuir probe, pulsed wave-cutoff method and frequency sweeping wave-cutoff method, are compared. The measurement results are well matched. The real time resolution is less than 1 ?sec. The pulsed wave-cutoff technique is found to be very useful in the transient plasmas such as pulsed plasma and tokamak edge plasma.

• 한국건설관리학회:학술대회논문집
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• 한국건설관리학회 2006년도 정기학술발표대회 논문집
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• pp.187-193
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• 2006

최근의 과학기술의 발전과 더불어 인공위성을 이용한 GPS 측량시스템의 실용화가 토목을 중심으로 한 건설현장에서도 두드러지고 있다. 특히 측량기준점을 확인하기 어려운 토목현장의 경우에는 GPS 측량의 유용성이 적극적으로 도입되어 실용화 단계에 이르렀다. 그러나 mm단위의 정밀성이 요구되는 건축현장의 경우에는 GPS가 가지는 오차의 크기로 인하여 적용되어 오지 못하다가 최근에 정밀도를 향상시킨 새로운 측량 기술이 개발되어 초고층 건물을 중심으로 적용되고 있다. 본 논문에서는 정확성과 편리성을 획기적으로 개선한 GPS 측량시스템을 세계초고층 건물인 버즈 두바이 현장에 적용한 사례를 소개하고자 한다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2000년도 하계학술대회 논문집 C
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• pp.1957-1959
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• 2000

The PD measurement method is very useful to detect insulation degradation. Recently, the HFPD(High Frequency Partial Discharge) measurement testing is widely used in partial discharge measurement of HV machines because HFPD measurement testing receives less influence of external noise and has a merit of good sensitivity. Therefore it is very useful method compare to previous conventional PD testing method and effective diagnosis method in power transformer that requires in-service diagnosis. But partial discharges have very complex characteristics of discharge pattern so it is required continuous research to development of precise analysis method. In this study, simulated transformer is manufactured and HFPD occurred from simulated transformer is measured with broad band antenna and active-line RF measurement system in real time, the degradation grade of transformer is analyzed through produced patterns in simulated transformer according to applied voltages. Also the PD pattern which was measured with EMC analyzer and RF measurement system is compared.

• 한국산업융합학회 논문집
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• 제25권2_2호
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• pp.299-307
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• 2022

Wireless earphones, along with smart devices, are the most sought-after products by consumers. Compared to general earphones, wireless earphones do not have twisted wires and are easy to use, so various types of products are currently on the market. However, information on quality is somewhat lacking, so consumers tend to purchase products according to brand awareness, and manufacturers are delivering information to consumers using different standards for each product because there is no standard for quality control. In particular, the playback time of wireless earphones is a factor that directly affects consumers' purchases, so a standard measurement method is needed to properly measure it. In this paper, we present a method for measuring the audio playback time of wireless earphones derived from domestic wireless earphone status survey, commercial product measurement test, and research analysis, and a developed standard measurement method. In addition, this paper proposes a measurement result reporting format to provide accurate information to consumers and induce a fair competitive environment for each product to manufacturers.