• Title/Summary/Keyword: Small-signal

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Research for Image Enhancement using Anti-halation Disk for Compact Camera Module (헤일레이션 방지 디스크를 이용한 소형 카메라 이미지 화질개선 연구)

  • Kim, Tae-Kyu;Song, In-Ho;Han, Chan-Ho
    • Journal of the Institute of Convergence Signal Processing
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    • v.17 no.1
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    • pp.26-31
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    • 2016
  • In this paper, we propose an image quality evaluation system for compact camera module and assess the effect of optical performance improvement for proposed anti-halation disk in small lens. We develop a image quality evaluation system for quality estimation of camera module image. And we also develop a program to control register in image signal processor. Finally the resolution, brightness, and color reproduction performances were evaluated image quality comparison between conventional and proposed camera module using developed quality evaluation system and ISP register control program.

A Design of Multi format HD LCD Monitor for Broadcasting (방송용 Multi format HD LCD Monitor의 설계)

  • Han, Sung-Il;Jun, Eung-Sup;Noh, Hyung-Il
    • Journal of the Korea Society of Computer and Information
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    • v.15 no.3
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    • pp.37-43
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    • 2010
  • In this study, the multi format 8.4" LCD monitor for broadcasting has been proposed by the simple circuit design and the efficient processing technique. The small sizing technique, the mixed-type video signal processing technique, the emerging skill of multi-format HD signal to one port, the dividing technique between the analog and digital signal, the embedded audio signal developing technique are the key researches of this study. The proposed multi format 8.4" LCD monitor has been focused on the broadcasting field and has been supposed to have the efficiency at that field.

Hardware design for SNR estimation of QAM modulation systems (QAM 변조 방식에 대한 SNR 추정을 위한 하드웨어 구현)

  • Jung, Man-Ho;Song, Sang-Seob;Kim, Soo-Young
    • Proceedings of the IEEK Conference
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    • 2006.06a
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    • pp.77-78
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    • 2006
  • This paper presents a signal quality estimation technique for QAM modulation systems. By making a LUT(Look-up table) putting the number of N enough, we can derive estimated SNR from LUT even though N is small. That is so called MOTM algorithm. In 16-QAM, the distance $d_a$, between adjacent symbols is always invariable, so absolute value of R(the amplitude of signal) minus $d_a$ has a always same signal distribution value. This value does not form a Gaussian shape but, by making a little bit correction, we can make this symmetrical. So, from the received symbol value, by using LUT we can easily derive the estimated SNR. By considering this, we introduce a signal quality estimation technique for QAM schemes. This proposed method can be applicable to high order modulation schemes and wide range of signal to noise ratio.

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Switching performances of multivarite VSI chart for simultaneous monitoring correlation coefficients of related quality variables

  • Chang, Duk-Joon
    • Journal of the Korean Data and Information Science Society
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    • v.28 no.2
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    • pp.451-459
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    • 2017
  • There are many researches showing that when a process change has occurred, variable sampling intervals (VSI) control chart is better than the fixed sampling interval (FSI) control chart in terms of reducing the required time to signal. When the process engineers use VSI control procedure, frequent switching between different sampling intervals can be a complicating factor. However, average number of samples to signal (ANSS), which is the amount of required samples to signal, and average time to signal (ATS) do not provide any control statistics about switching performances of VSI charts. In this study, we evaluate numerical switching performances of multivariate VSI EWMA chart including average number of switches to signal (ANSW) and average switching rate (ASWR). In addition, numerical study has been carried out to examine how to improve the performance of considered chart with accumulate-combine approach under several different smoothing constant and sample size. In conclusion, process engineers, who want to manage the correlation coefficients of related quality variables, are recommended to make sample size as large and smoothing constant as small as possible under permission of process conditions.

A Study on the Adaptive Neural Network Filter for Signal Detection (신호 검출을 위한 적응형 신경망 필터에 관한 연구)

  • 안종구;추형석
    • Journal of the Institute of Convergence Signal Processing
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    • v.5 no.2
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    • pp.132-137
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    • 2004
  • In this paper, the adaptive noise canceler using neural network with backpropagation is designed. The adaptive noise canceler using the least mean square algorithm has the large correlativity of the reference signal. The performance of the adaptive noise canceler shows the limitation when the information signal is relatively small to the noise. The system proposed in this paper plays an important role in denoising these signals. In addition, the experiments are carried out to analyze the effects of the number of hidden layers and nodes about the system. The performance of the proposed adaptive noise canceler is compared with that of the system which is used the least mean square algorithm.

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Speed Control of DC Motor for Roller Type Seeder (롤러형 파종기 구동용 직류모터의 회전속도 제어)

  • 이중용;김유용;박상래
    • Journal of Biosystems Engineering
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    • v.25 no.5
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    • pp.351-358
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    • 2000
  • This study was conducted to develop a speed control system of a DC motor which drove a barley seeder mounted on a combine harvester. Barley seeder mounted on a combine has been known to reduce labor and cost of barley cultivation. However, development of the seeder has been unsuccessful because the combine, a dedicated rice and barley harvester has not enough space and proper power take-off for barley seeder. To develop a barley seeder, small powered motor speed controller was required. A proximity sensor for detecting working speed of the combine and a programmable one board microprocessor was used to develope a control system. Motor parameters and motor constant, relationship between seeding rate, motor speed, groove volumes of a tested roller, torque were measured. The proximity sensor sent a frequency signal to the microprocessor. In laboratory experiments, the excitation voltage of the motor was shown not to be proportional to the size of pulse width (duty ratio). A table transforming frequency signal, that represented for working speed to proper pulse width was developed from seeding rate experiments. However, seeding rate at low frequency signal was not proportional to the working speed. Seeding rate control proportional to the frequency signal was achieved by shifting of the frequency signal.

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A study on the determination of Ultrasonic Travel Time by Norm Phase-Time Method (위상시간법에 의한 초음파전파시간의 결정에 관한 연구)

  • 이은방
    • Journal of the Korean Institute of Navigation
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    • v.18 no.4
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    • pp.137-146
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    • 1994
  • In this paper, a new algorithm to measure the ultrasonic travel time is proposed, which is fundamental to estimate distance depth and volume in several media. Pulse wave has been used to measure travel time of transmitted signal. However, due to the characteristic of transducer and propagation, the received signal is so distorted that it is difficult to measure travel time, which is propagation, the received signal is so distorted that it is difficult to measure travel time, which is to be time difference between transmitted and received signals. In this proposed method, transmitted and received signal are transformed respectively into norm phase newly designed by this paper and displayed on phase-time curve. And travel time is simply determined by the arithmetic numerical mean of time difference at the identical norm phase on the phase-time curves of transmitted and received signals. This method has several features; firstly, travel time is calculated analytically with high accuracy by least square error method, secondly, it is useful to compare the difference of signal magnitude for time information, thirdly, noise and discrete errors are relatively small, finally, the measurement accuracy is not influenced by D.C. bias. In particular, this method is useful and applicable to measuring very short distance and sound speed with high accuracy.

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Improved Dynamic Programming in Local Linear Approximation Based on a Template in a Lightweight ECG Signal-Processing Edge Device

  • Lee, Seungmin;Park, Daejin
    • Journal of Information Processing Systems
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    • v.18 no.1
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    • pp.97-114
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    • 2022
  • Interest is increasing in electrocardiogram (ECG) signal analysis for embedded devices, creating the need to develop an algorithm suitable for a low-power, low-memory embedded device. Linear approximation of the ECG signal facilitates the detection of fiducial points by expressing the signal as a small number of vertices. However, dynamic programming, a global optimization method used for linear approximation, has the disadvantage of high complexity using memoization. In this paper, the calculation area and memory usage are improved using a linear approximated template. The proposed algorithm reduces the calculation area required for dynamic programming through local optimization around the vertices of the template. In addition, it minimizes the storage space required by expressing the time information using the error from the vertices of the template, which is more compact than the time difference between vertices. When the length of the signal is L, the number of vertices is N, and the margin tolerance is M, the spatial complexity improves from O(NL) to O(NM). In our experiment, the linear approximation processing time was 12.45 times faster, from 18.18 ms to 1.46 ms on average, for each beat. The quality distribution of the percentage root mean square difference confirms that the proposed algorithm is a stable approximation.

The Coordination of Pyridyl-N to Pentacyanoferrate for the Electrochemical Detecting Small Organic Molecules

  • Choi, Young-Bong;Jeon, Won-Yong;Kim, Hyug-Han
    • Bulletin of the Korean Chemical Society
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    • v.34 no.2
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    • pp.595-599
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    • 2013
  • The coordination of pyridyl-N to pentacyanoferrate for the detection of small organic antigens in solution is presented. The unique contribution of this paper is the direct conjugation of pyridyl-N in small organic antigens to pentacyanoferrate. Pentacyanoferrate is promising as an electrochemical label owing to its good electro-chemical properties, which can be utilized to generate an electrical signal in homogeneous electrochemical immunoassays. The facilely synthesized pyridyl-N to pentacyanoferrate was characterized by the electrochemical and spectroscopic methods. Hippuric acid (HA) has been detected competitively on the interaction of free HA and pentacyanoferrate-(4-aminomethylpyridine-hippuric acid) (Fe-HA) to its antibody, with the detection limit of 0.50 ${\mu}g\;mL^{-1}$. While pentacyanoferrate-based immunoassay is in its simplicity and infancy, the proposed immunoassay offers attractive opportunities for developing pyridyl-N-based the electrochemical detection of small organic antigens in the health care area.

Fiber Fabry-Perot interferometric sensor for the measurement of current flowing into a small fuse (소형 퓨즈에 흐르는 전류 측정용 광섬유 패브리-페로 간섭형 센서)

  • Park, Sung-Sun;Park, Jae-Hee;Kim, Kyung-Chan
    • Journal of Sensor Science and Technology
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    • v.14 no.2
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    • pp.91-95
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    • 2005
  • A fiber Fabry-Perot interferometric sensor for the measurement of current flowing into a small fuse have been studied. The proposed current sensor was fabricated with a fiber Fabry-Perot interferometer attached close to a fuse line inside a small fuse. The fiber Fabry-Perot interferometer used in the experiment had the 10 mm cavity length and the 3.5 % reflectance mirrors. The phase shift of the output signal of the current sensor was proportional to the square of current applied to the fuse and the sensitivity of the current sensor was 0.87 degree/$mA^{2}$. The experiment results show that this sensor can be used for measuring current flowing into the fuse.