• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2004년도 춘계학술대회논문집
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• pp.770-773
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• 2004

The transmission loss coefficient is very important acoustic property in parallel with absorption and acoustic impedance categorizing the acoustical materials, which can control the acoustical problems. At the same time, the transmission loss coefficient is a key parameter to choose the optimum material for the analysis of acoustical characteristics of material using SEA(Statistical Energy Analysis). In this paper, the acoustic transmission loss measurement system using 4-microphone TL tube is applied to the exhaust system, which is one of the most important acoustic control parameters in a car, based on the idea calculating the full transfer matrix. The theoretical background and measurement system are introduced, and finally the measurement results are verified.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2003년도 춘계학술대회논문집
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• pp.658-661
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• 2003

The transmission loss coefficient is very important acoustic property in parallel with absorption and acoustic impedance categorizing the acoustical materials, which can control the acoustical problems. At the same time, the transmission loss coefficient is a key parameter to choose the optimum material for the analysis of acoustical characteristics of material using SEA(Statistical Energy Analysis). In this paper, the transmission loss coefficient measurement system using 4-microphone impedance tube is proposed, based on the idea calculating the full transfer matrix of the acoustical sample to test. The theoretical background and measurement system are introduced, and finally the measurement results are verified.

• International Journal of Aeronautical and Space Sciences
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• 제18권3호
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• pp.555-564
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• 2017

In this paper, a new technique for attitude and heading reference system (AHRS) using low-cost MEMS sensors of the gyroscope, accelerometer, and magnetometer is addressed particularly in vibration environments. The motion of MEMS sensors interact with the scale factor and cross-coupling errors to produce random errors by the harsh environment. A new adaptive attitude estimation algorithm based on the Kalman filter is developed to overcome these undesirable side effects by analyzing windowed measurement error covariance. The key idea is that performance degradation of accelerometers, for example, due to linear vibrations can be reduced by the proposed measurement error covariance analysis. The computed error covariance is utilized to the measurement covariance of Kalman filters adaptively. Finally, the proposed approach is verified by using numerical simulations and experiments in an acceleration phase and/or vibrating environments.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2000년도 추계학술대회논문집
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• pp.322-326
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• 2000

This paper is concerned with the development of remote vibration measurement system using the internet. Recently, various techniques are developed based on the advance of the internet environment. In this study, we developed the remote vibration measurement system using the internet server programming technique, the client programming technique, the GPIB programming, and the A/D, D/A programming techniques. Hence, we can control the measurement devices remotely. The feasibility of the system is validated using the experimental setup. The output of the D/A is connected to the small exciter and the piezoceramic sensor is connected to the A/D port. By sending out the exciting signal to the structure, we can collect the response. The experiment shows that the proposed idea works well. Another experiment consists of the function generator and the low-pass filter circuit. The wave form, amplitude, and the frequency of the function generator is controlled by the GPIB program and the output of the circuit is collected by the A/D port. The output is then displayed in HTML format.

• 경영과정보연구
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• 제21권
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• pp.49-76
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• 2007

The main purpose of this study is to assess the relationship between communication satisfaction and group creativity. To achieve this purpose, this study has two objectives. First, I will identify the relationship between the satisfaction of communication and idea creation. Second, the relationship between communication satisfaction and problem solving activity will be statistically tested. The major findings of the study can be summarized as follows: First, Statistically significant positive relations were found between the communication satisfaction and idea creation. Especially, sub-construct for supervisor communication$({\beta}=0.14,\;p<.05)$, quality of media$({\beta}=0.13,\;p<.05)$, individual feedback$({\beta}=0.36,\;p<.001)$, organizational prospect$({\beta}0.31,\;p<.001)$ showed the statistically significant positive(+) relationship with construct in idea creation. Second, the measurement of communication satisfaction had showed statistically significant relationship with the problem solving activity. Especially, communication with supervisor$({\beta}=0.21,\;p<.05)$, quality of media$({\beta}=0.21,\;p<.001)$, organizational prospects$({\beta}=0.22,\;p<.001)$, and communication with subordinate$({\beta}=0.37,\;p<.001)$ showed the significant positive(+) relationship with problem solving activity construct. These consequences suggest that communication satisfaction of employee is effective in the improving the group creativity in organization. In the conclusion, this study present the satisfaction factor of employee communication as a incremental factor of group creativity.

• 한국인터넷방송통신학회논문지
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• 제21권3호
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• pp.193-200
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• 2021

본 연구는 창의적 문제해결력 평가를 위한 요인을 탐색하고 측정 항목을 규명하기 위해 진행하였다. 선행 연구와 설문을 통해 7개의 요인과 26개의 예비 문항을 얻을 수 있었다. 창의적 문제해결 역량과 관련하여 문제해결 절차 면에서 문제 발견 능력, 아이디어 생성 능력, 아이디어 평가 능력, 아이디어 실행 능력을 확인하였다. 또한, 문제해결 수행자간의 상호작용 능력과 문제 해결 수행자의 창의적 효능감 요인이 탐색 되었다. 마지막으로 HTE 창의교육 모델의 창의적 문제해결력 요인으로 은유와 비유적 인지 사고 능력과 그에 대한 평가 항목을 제시하였다. 후속 연구를 통해 HTE 창의 교육 평가 모델의 초석이 되기를 기대한다.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제9권9호
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• pp.3559-3571
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• 2015

This paper addresses the problem of signal acquisition with a sparse representation in a given orthonormal basis using fewer noisy measurements. The authors formulate the problem statement for randomly measuring with strong signal noise. The impact of white Gaussian signals noise on the recovery performance is analyzed to provide a theoretical basis for the reasonable design of the measurement matrix. With the idea that the measurement matrix can be adapted for noise suppression in the adaptive CS system, an adapted selective compressive sensing (ASCS) scheme is proposed whose measurement matrix can be updated according to the noise information fed back by the processing center. In terms of objective recovery quality, failure rate and mean-square error (MSE), a comparison is made with some nonadaptive methods and existing CS measurement approaches. Extensive numerical experiments show that the proposed scheme has better noise suppression performance and improves the support recovery of sparse signal. The proposed scheme should have a great potential and bright prospect of broadband signals such as biological signal measurement and radar signal detection.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2005년도 춘계학술대회 논문집
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• pp.569-572
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• 2005

Technological feasibility of using recently-available femtosecond ultra short pulse lasers for advanced precision length metrology is investigated with emphasis on absolute distance measurements with $10{\mu}m$ ??resolution over extensive ranges. The idea of using femtosecond lasers for the measurement of absolute distances is based on the fact that a short pulse train is a mode-locked combination of discrete monochromatic light components spanning a wide spectral bandwidth. The synthetic wavelength is created from the repetition frequency, $f_r$ of the femtosecond laser and for more precise resolution, higher-order harmonics of the repetition frequency may be selected as the synthetic wavelength by using appropriate electronic filters.

• 품질경영학회지
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• 제27권3호
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• pp.94-112
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• 1999

It is booming to use computer and information owing to the information society. As software applications have grown, so too has the importance of software quality. Therefore, software quality measurement and evaluation are necessary to satisfy the users who are using computers. The ISO/IEC 9126 defines six quality characteristics and twenty-one subcharacteristics including forty inter quality characteristics. We developed software measurement and evaluation technique using the check list in accordance with the ISO/IEC 9126 in design phase. We applied idea and concept of Total Quality Management in order to evaluate and measure the quality of software. Namely, it is the concept such as "you should do it right the first time." or "you have to build quality in the process." We executed the quantitative evaluation of software, also had shown the distinctive result in order that users and developers can find the errors easily. We evaluated the quality of academic softwares in order to verify developing technique at S college. As a result of the evaluation, this college has found it necessary to maintain the software as soon as possible because academic systems are not adequate for users at this present time.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2003년도 춘계학술대회
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• pp.845-850
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• 2003

The scattered light pattern from a machined surface generally contains much information concerning the surface roughness. The light pattern can be acquired by optical system and analyzed by statistical method. This kind of surface roughness measurement system can be easily adopted on the machine measurement. But the fully assembled system is too complex to implement on small systems using micro-controller. This study proposes the idea of reducing the number of optical components by removing screen and examines image processing of a light pattern to minimize the negative result of incomplete optical system. And the Gaussian blur filtering is concluded to be the best method of proposed measurement system. Furthermore light intensity variation of image pattern can be treated as a signal, therefore FIR filtering gives the similar result of Gaussian blur effect.