• 한국안전학회지
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• 제12권4호
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• pp.3-8
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• 1997

This paper shows a performance estimation of windowing a single tone with added Gaussian noise and uniform noise. Signal-to-noise ratio can be determined by the ratio of the output noisy signal variance to the input noisy signal variance of a window. Standard deviation of noise is reduced by windowing Signal-to-noise ratio of the noisy signal is reduced by the windowing operation. Thus, performance of window function can be determined by this filtering operation that improved the signal-to-noise ratio.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2001년도 추계학술대회 논문집 전기기기 및 에너지변환시스템부문
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• pp.51-53
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• 2001

Permanent Magnet DC Motors are widely used in Automotive parts because they have cheap price, simple structure and high torque-speed ratio. But the motor in automotive parts is required high quality, complex function and lower price than before. This paper deals with design of controller for safety function that body trap on the automotive window. The algorithm of controller can adapt variety conditions with temperature, electrical, driving, etc.

• 한국소음진동공학회논문집
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• 제17권9호
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• pp.888-894
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• 2007

The speech sound is detected by the vibration measurement of the window glass. In this study, we investigate the effect of the disturbing waves by background noise and window shaker excitation on the speech intelligibility of the detected sound. Based upon Modulation Transfer Function(MTF), speech intelligibility of the sound is objectively estimated by Speech Transmission Index(STI) As the level of the disturbing wave varies, variation of the speech intelligibility is examined. Experimental result reveals how STI is influenced by the level and frequency characteristics of the disturbing wave. By using a customized window shaker for disturbing sound, we evaluate the efficiency and the frequency characteristics of the anti-eavesdropping system. The purpose of the study is to provide useful information to prevent the eavesdropping through the window glass.

• 전기전자학회논문지
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• 제23권2호
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• pp.395-402
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• 2019

In this paper, we implemented an Ultra-Wideband radar system using Stripmap Synthetic Apertrure Radar algorithm to recognize objects inside a box. Different window functions such as Hanning, Hamming, Kaiser, and Taylor functions to improve image recognition performance are applied and implemented to radar system. The Ultra-Wideband radar system with 3.1~4.8 GHz broadband and UWB antenna were implemented to recognize the conductor plate located inside 1m3 box. To obtain the image, we use the propagation data in the time domain according to the 1m movement distance and use the Range Doppler algorithm. The effect of different window functions to improve the recognition performance of the image are analyzed. From the compared results, we confirmed that the Kaiser window function can obtain a relatively good image.

• 한국통신학회:학술대회논문집
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• 한국통신학회 1983년도 추계학술발표회논문집
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• pp.61-64
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• 1983

It is shown that the new window function of Exponential type can be derived from Cheby-chev Identity for the design of FIR filter, and the various kinds of windows which have different characterristics can also be made by changing the coefficients of them oasily

• 대한의용생체공학회:학술대회논문집
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• 대한의용생체공학회 1992년도 추계학술대회
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• pp.79-82
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• 1992

Under the assumption that the EMG signal was used as the reference signal for driving a prosthetic arm, function discrimination of EMG signal from the biceps and triceps of subject was achived with LPC CEPSTRUM coefficients. By varying the number of coefficients, the types of windows, window size, and window overlaping rates, the best conditions for the function discrimination of EMG signal were obtained.

• 한국수자원학회논문집
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• 제32권6호
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• pp.731-740
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• 1999

자기상관함수는 수문시계열의 선형상관 관계를 나타내는 척도롤 널리 이용되고 있다. 그러나 비선형 동역학에서 필수적인 지체시간 또는 무상관시간 $\tau$d를 산정하는데는 적합하지 않을수도 있기 때문에 비선형 상관관계의 척도로 상호정보이론이 추천되어 왔다. 최근에 일부 학자들은 카오스 동역학 분석을 위하여 지체신간 $\tau$d대신에 상태 공간상에 구축된 각 상태 벡타점 성분들의 총시간을 표시하는 지체시간창을 제안하였다. 그러나 지체신간창은 자기상관함수나 상호정보이론에 의해 추정될 수 없다. 기본적으로 지체신간창은 시계열 자료의 상관관계가 가장 작을 최적시간이며 지체시간은 국지적인 최소값 중 첫 번째의 최적시간이다. 본 연구에서는 수문시계열의 지체시간과 지체사간창을 구하기 위하여 C-C밥법이라는 기법을 이용하고, 여기에서 산정된 값들을 근거로 수문시계열의 모형화와 예측에 중요한 선형 또는 비선형 종속성을 파악하고자 한다.

• 한국소음진동공학회논문집
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• 제20권6호
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• pp.568-576
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• 2010

It is widely known that the leak locating of underground plastic pipelines is much more difficult than that of cast iron pipelines. The precision of the leak locating depends upon the speed of leak signal and the time delay estimation between the two sensors on the pipeline. In this paper, six different windowing filters are considered to improve the time delay estimation especially for the plastic pipelines. The time delay is usually estimated from the peak time of cross-correlation functions. The filtering windows including rectangle, Roth, Wiener, SCOT, PHAT and maximum likelihood are applied to derive the generalized cross-correlation function and compared each other. Experimental results for the actual plastic underground water supply pipeline show that the introduction of the filtering windows improved the precision of time delay estimation. Some window functions provide excellent leak locating capability for the plastic pipe of 98 m long, which is less than 1 % of the pipe lengths. Also a new probabilistic approach that the combinations of all results from each filtering window is suggested for the better leak locating.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제4권5호
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• pp.896-909
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• 2010

IEEE 802.11 medium access control (MAC) employs the distributed coordination function (DCF) as the fundamental medium access function. DCF operates with binary exponential backoff (BEB) in order to avoid frame collisions. However it may waste wireless resources because collisions occur when multiple stations are contending for frame transmissions. In order to solve this problem, a binary negative-exponential backoff (BNEB) algorithm has been proposed that uses the maximum contention window size whenever a collision occurs. However, when the number of contending stations is small, the performance of BNEB is degraded due to the unnecessarily long backoff time. In this paper, we propose the adaptive BNEB (A-BNEB) algorithm to maximize the throughput regardless of the number of contending stations. A-BNEB estimates the number of contending stations and uses this value to adjust the maximum contention window size. Simulation results show that A-BNEB significantly improves the performance of IEEE 802.11 DCF and can maintain a high throughput irrespective of the number of contending stations.

• 한국기계가공학회지
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• 제7권1호
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• pp.22-31
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• 2008

The operating window method is a novel approach in quality improvement. But it has not received deserved attention in academic research. If a critical factor for competing failure modes can be identified, the probability of failure can be reduced by widening the operating window of this factor. Traditional SN ratio for the operating window advocated by Taguchi has a critical shortcoming, which has been derived under the assumption that failure rates are determined by the operating window factor only. A new metric for robustness is given for the operating window method, which has relaxed the restrictive assumption of Taguchi's SN ratio. And procedures for determining optimal conditions based on the new metric is presented. The effectiveness of the proposed approach over the traditional practice is tested with the aid of a wave soldering process.