• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2008년도 International Meeting on Information Display
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• pp.1362-1365
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• 2008

ED-2523 (Measuring methods for matr ix reflective LCD modules) was published by JEITA (Japan Electronics and Information Technology Industries Association) in 2001. Since then, round robin tests had been done and the accuracy of measurement values had been discussed. In this paper, considerations for error factors in four measurement systems are showed.

• 한국분무공학회지
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• 제25권2호
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• pp.51-59
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• 2020

The purpose of this study is to propose and compare methods for measuring individual spray cone angles using spray cross-section images. In direct injection gasoline engines, it was believed that the distribution of air-fuel mixture in the combustion chamber directly affected combustion performance and emission formation. However, since gasoline direct injection (GDI) injectors have a small injection angle, interference between individual spray plumes occurs. Therefore, GDI injectors have only measured the spray angle of the entire spray. To overcome these limitations, three methods of indirectly measuring the spray cone angles of individual spray plume were presented and compared by forming sheet beams using Nd:YAG laser and acquiring spray cross-section images. Each method currently has advantages and disadvantages, and research to apply the method suitable for various GDI injectors needs to be continued.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2003년도 추계학술대회 논문집(I)
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• pp.167-174
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• 2003

Recently, the "ride comfort" problem becomes increasingly important because of today′s needs for train speedup. The concept of term "ride comfort" is equivocal. Generally it is defined as the vehicle vibration. There are many studies on evaluation method of ride comfort for railway. But each of them recommends the different assessment method and the different guidance. So users must review whether they can apply it to their system or not. In general, the evaluation methods defined in the standards - ISO 2631, UIC 513 R, and Ride Index suggested by Sporting - have been used in the railroad. The ride comfort measuring system according to the previous mentioned evaluation methods "ride comfort" has developed, verified and utilized in the railways.

• 한국가정과교육학회지
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• 제7권1호
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• pp.1-10
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• 1995

This study was intended to provide an improved method for testing textiles in high school. Four kinds of test subjects were selected and applied to the classes. Problems of the methods in the textbooks were corrected as follows: 1)Burning test: The number of specimen is reduced to 3 kinds of fibers(cotton, wool, and polyester) and recommends are given to make result by comparing with the burning characteris-tics of paper and hair. 2) Absorbency test: Test Method is changed to drop test. The result is recorded by measuring time required for the water drops absorbed to the specimen. 3) Wrinkle recovery test: A glass is provided instead of metal weight. The method of measuring angle which is made by the specimen is shown in figure. 4) Effects of Detergent: 0.2% of detergent solution is provided before class. The amount of oil and carbon black is specified. Students have generally agreed that the improved methods were better than those in the text-books after they made the above 4 recommendable experiments(p<.001)

• 한국정보통신설비학회:학술대회논문집
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• 한국정보통신설비학회 2006년도 하계학술대회
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• pp.145-150
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• 2006

For most of the measuring methods of traditional control theory, measuring equipments are located at the output of the system to measure quantities transformed from non-electrical form into electrical one. This method helps us to define the value of parameters to be measured, but it has limitation because it can only assess the efficiency of a movement process. That means we can not understand the inner kinetics which is the essence of the system. In the modern control theory, states of system are considered as the feedback to the control process, which helps us to assess the elements in the inside of the system. In this paper, we survey methods for estimating states being not exposed to the correct measurements. Using this method, we also suggest an application for giving an estimate of the traffic on the LSPs to adapt the network configuration for changing traffic conditions.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2006년도 춘계학술대회 논문집
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• pp.283-284
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• 2006

In this paper 3-point weighing method is adopted to measure the unbalance moment of small-sized precision spinning elements using electronic scales with 0.1 mgf resolution. Firstly methods to eliminate the fixture error and to reduce the effects of frictional force that is known as side effect, are proposed. A measuring system is developed and various experiments are performed to verify the proposed approach. The measured and calculated values are analysed in statistical methods, and this provides the errors of the measuring system. The results show that the proposed theory and test procedures gives reliable unbalance moments and gravitational centers.

• Korean Journal of Hydrosciences
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• 제8권
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• pp.57-68
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• 1997

The daily soil water contents were obtained from the time domain reflectometry(TDR) method and energy balance-water budget approach with eddy correlation at the two small semiarid watersheds of Lucky Hills and Kendall during the summer rainy period. There was a comaprison of daily soil water content measured and estimated from these two different approaches. The comparison is valuable to evaluate the accuracy of current soil water content measuring system using TDR and energy balance-water budget approach using eddy correlation method at a small watershed scale. The degree of simiarity between the regressions of these two methods of measuring soil water content was explained by determining the correlations between these methods. Simple linear regression analyses showed that soil water content measured from TDR method was responsible for 58% and 63% of the variations estimated from energy balance-water budget approach with edy correlation at Lucky Hills and Kendall, respectively. The scatter plots and the regression analyses revealed that two different approaches for soil water content measurement at a small watershed scale have no significant difference.

• 한국소음진동공학회논문집
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• 제22권11호
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• pp.1106-1112
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• 2012

This paper deal with a technique for monitoring machining conditions by measuring the vibration of cutting forces at milling machining. The vibrations of cutting forces in milling process were measured and analyzed to be related with processing parameters. The magnitude of cutting force is linearly proportional to the feed rate and cutting depth, and frequency of cutting force is linearly proportional to the rotating speed. Wired and wireless communication methods were applied in transmitting the measured vibration signals and the two methods were compared. The magnitude of the vibration signals transmitted by the wireless communication method was similar to that transmitted by the wired communication method.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2006년도 추계학술대회 논문집
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• pp.376-380
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• 2006

There are several methods which estimate the behavior of the Structures. Recently, several displacement measuring instruments such a GPS are substantially developed. So, considering this technique, displacement measurement will be a very efficient method for estimating the behavior of the Structures and maintenance. Therefore we need to develop methods of structure maintenance & management by using displacement measuring instruments. In this study, I suggest to maintenance & management method by using displacements about simple beams and cantilever beams which are very important structure in civil engineering. The results show that the proposed method is capable of estimating the displacement and stress of the Beam Member by combining the proper number of measurement and optimum measurement points.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2007년도 하계학술대회 논문집
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• pp.211-213
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• 2007

The electrical parameters are used to calculate gains in the current regulator as well as to determine the reference currents of speed controller in various control strategies of Synchronous Reluctance Motors (SynRMs). Many methods of measuring or estimating the electrical parameters of SynRM have been proposed by other authors. But almost papers only measure or estimate in the limited conditions without fully considering the effects of inverter, connecting wire and magnetic saturation. The parameter results are usually different from the real system parameters. The drive performance, therefore, can not be good if using inaccurate parameters. In this paper, several methods used to measure the electrical parameters are introduced. The first method is LCR meter. And then, a method determining inductances by measuring AC current and voltage from AC power supply is presented. A new method with high reliability is proposed to measure the electrical parameters of SynRM. The experiment results verify the effectiveness of the new proposed method.