• Title/Summary/Keyword: multichannel system

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A Study on the Shift Register-Based Multi Channel Ultrasonic Focusing Delay Control Method using a CPLD for Ultrasonic Tactile Implementation (초음파 촉각 구현을 위한 CPLD를 사용한 Shift Register기반 다채널 초음파 집속 지연 제어 방법에 대한 연구)

  • Shin, Duck-Shick;Park, Jun-Heon;Lim, Young-Cheol;Choi, Joon-Ho
    • Journal of Sensor Science and Technology
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    • v.31 no.5
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    • pp.324-329
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    • 2022
  • This paper proposes a shift-register-based multichannel ultrasonic focusing delay control method using a complex programmable logic device (CPLD) for a high resolution of ultrasonic focusing system. The proposed method can achieve the ultrasonic focusing through the delay control of driving signals of each ultrasonic transducer of an ultrasonic array. The delay of the driving signals of all ultrasonic channels can be controlled by setting the shift register in the CPLD. The experiment verified that the frequency of the clock used for the delay control increased, the error of the focusing point decreased, and the diameter of the focusing point decreased as the length of the shift register in the proposed method. The proposed method used only one CPLD for ultrasonic focusing and did not require to use complex hardware circuits. Therefore, the resources required for the design of an ultrasonic focusing system could be reduced. The proposed method can be applied to the fields of human computer interaction (HCI), virtual reality (VR) and augmented reality (AR).

Influence of Sensor Noise on the Localization Error in Multichannel SQUID Gradiometer System (다채널 스퀴드 미분계에서 센서 잡음이 위치추정 오차에 미치는 영향)

  • 김기웅;이용호;권혁찬;김진목;정용석;강찬석;김인선;박용기;이순걸
    • Progress in Superconductivity
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    • v.5 no.2
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    • pp.98-104
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    • 2004
  • We analyzed a noise-sensitivity profile of a specific SQUID sensor system for the localization of brain activity. The location of a neuromagnetic current source is estimated from the recording of spatially distributed SQUID sensors. According to the specific arrangement of the sensors, each site in the source space has different sensitivity, that is, the difference in the lead field vectors. Conversely, channel noises on each sensor will give a different amount of the estimation error to each of the source sites. e.g., a distant source site from the sensor system has a small lead-field vector in magnitude and low sensitivity. However, when we solve the inverse problem from the recorded sensor data, we use the inverse of the lead-field vector that is rather large, which results in an overestimated noise power on the site. Especially, the spatial sensitivity profile of a gradiometer system measuring tangential fields is much more complex than a radial magnetometer system. This is one of the causes to make the solutions of inverse problems unstable on intervening of the sensor noise. In this study, in order to improve the localization accuracy, we calculated the noise-sensitivity profile of our 40-channel planar SQUID gradiometer system, and applied it as a normalization weight factor to the source localization using synthetic aperture magnetometry.

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Performance Analysis of WFMT Modulation System Robust to ICI and Doppler Effect (부반송파간 간섭과 도플러 효과에 강한 WFMT 변조 방식의 성능 분석)

  • Kim, Seon-Ae;Ryu, Heung-Gyoon
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.19 no.10
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    • pp.1137-1146
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    • 2008
  • OFDM is very effective for the high speed communication system. However, OFDM has the problems of high PAPR and serious ICI, which is different from the single carrier system. Especially, ICI problem caused by phase noise, Doppler effect and frequency offset is main reason for poor performance since it breaks down the orthogonality between subcarriers in OFDM communication system. Therefore, WFMT modulation scheme is studied and the effect of the carrier frequency offset and phase noise is analyzed. WFMT modulation scheme is based on the wavelet theory and complex filter banks for synthesis and analysis of multichannel signal. WFHT modulation scheme keeps on the advantage of filter banks system and can be easily possible for the implementation of filter banks. In this paper, we compare ISI and ICI distortions of the WFMT and OFDM system due to the carrier frequency offset and phase noise. Also, we analyze the PAPR and BER performances in the HPA and ICI situation caused by the Doppler frequency shift and the frequency offset.

Low-Power Implementation of A Multichannel Hearing Aid Using A General-purpose DSP Chip (범용 DSP 칩을 이용한 다중 채널 보청기의 저전력 구현)

  • Kim, Bum-Jun;Byun, Joon;Park, Young-Cheol
    • The Journal of Korea Institute of Information, Electronics, and Communication Technology
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    • v.11 no.1
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    • pp.18-25
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    • 2018
  • In this paper, we present a low-power implementation of the multi-channel hearing aid system using a general-purpose DSP chip. The system includes an acoustic amplification algorithm based on Wide Dynamic Range Compression (WDRC), an adaptive howling canceller, and a single-channel noise reduction algorithm. To achieve a low-power implementation, each algorithm is re-constructed in forms of integer program, and the integer program is converted to the assembly program using BelaSigna(R) 250 instructions. Through experiments using the implementation system, the performance of each processing algorithm was confirmed in real-time. Also, the clock of the implementation system was measured, and it was confirmed that the entire signal processing blocks can be performed in real time at about 7.02MHz system clock.

Design of Multichannel Telemetering IC for Physiological Signals (생체 신호처리를 위한 다채널 텔레미터용 IC 설계)

  • Park, Jong-Dae;Seo, Hee-Don;Choi, Se-Gon
    • Journal of Sensor Science and Technology
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    • v.1 no.2
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    • pp.147-154
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    • 1992
  • This paper describes the design of implantable 8-channel telemetering system to get physiological signals. The internal circuits of this system are designed not only to achieve as small size and low power dissipation as possible, but also to enable continuous measurement of physiological signals. Its main functions are to enable continuous measurement of physiological signals and to accomplish on-off power switching of an implantable battery by receiving appropriate command signals from an external circuit. To integrate implantable biotelemetry system, we performed layout of internal system using Lambda based $2{\mu}m$ n-well design rules. This system, used together with appropriate sensors, is expected to be capable of measuring and transmitting such significant parameters as pressure, pH, and temperature.

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A Study on Characteristics Analysis of Multichannel Filter Module for Near-infrared Fluorescence Imaging (근적외선 형광 이미징 영상 구현을 위한 다채널 필터 모듈 특성분석 연구)

  • Choi, Jinsoo;Cho, Sang Uk;Kim, Doo-In;Lee, Hak-Guen;Choi, Hak Soo;Jeong, Myung Yung
    • Journal of the Microelectronics and Packaging Society
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    • v.23 no.1
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    • pp.29-34
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    • 2016
  • In this study, development of multichannel filter module and characteristic evaluation for bio imaging were studied. The filter module was fabricated in order to realize near infrared fluorescence imaging of 700 nm and 800 nm wavelength ranges, and contrast imaging analysis for characteristic evaluation of the filter module was studied through signal to back ground ratio (SBR), controlled by parameters such as magnification, exposure, gain. Furthermore, phantoms, which are biomimetic tissue with equal optical properties of kidney and liver, were fabricated to study characteristics of both filter module depending on thickness and exposure amount of light source for bio imaging analysis. The fabricated filter module has more than 4 of SBR difference despite changes of magnification, exposure, gain, and in the case of the kidney phantom and the liver phantom, contrast imaging of more than 4 of SBR was confirmed on 50 mA, 60 mA exposure amount of light source respectively.

Omnichannel's Perception Effect on Omnichannel Use and Customer-Brand Relationship (옴니채널의 지각된 편리성과 유용성이 옴니채널 사용과 소비자-브랜드 관계에 미치는 영향)

  • Yim, Duk-Soon;Han, Sang-Seol
    • Journal of Distribution Science
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    • v.14 no.7
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    • pp.83-90
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    • 2016
  • Purpose - This study focuses on new type distribution channel that named as Omnichannel. Omnichannel is developed from Multichannel which is used in many distribution channels to buy or selling goods. Omnichannel basically needs an Information and Communications Technologies(ICT) to use, so researcher conduct a Technology Acceptance Model(TAM) to research model. Customer-brand relationship was used as dependent variable to focus on the role of Omnichannel. Research design, data, and methodology - The subject of this study is customer who purchase goods or service through omnichannel. Based on the literature from the preceding research analysis of TAM and customer-brand relationship, this study was constructed by the reference to previous studies, final research model design for figure out casual relationship among perceived ease of use, perceived usefulness, omnichannel use and customer-brand relationship. From 2016 February 3 to March 17, questionnaire survey targeted customers who use online and offline channels. 273 questionnaire survey had conducted, then, 252 survey data were available for empirical analysis. Researcher provide descriptive statistics for checking generality. Cronbach's alpha value was used to check the reliability of data. Exploratory factor analysis was used for purification of values and eigenvalue checking. After EFA, Confirmatory factor analysis was used to prepare structural equation modeling with executing structural equation modeling for confirming hypothesis which developed by researcher. Results - The main results of this empirical study are as follows. First, omnichannel's perceived ease of use has positive significant effect on perceived usefulness(estimate: 0.579). Moreover, omnichannel's perceived ease of use and perceived usefulness has positive significant effect on omnichannel use(estimate: 0.325,0.648). Second, using omnichannel has positive significant effect on brand-customer relationship(estimate: 0.521). Every hypothesis adopted as researcher designed. This study found out the intermediate relationship between perceived ease of use and omnichannel use by investigating hypothesis. Conclusions - Base on the empirical result, this study confirmed that TAM theory perceived has relation with omnichannel. First, factors of TAM has positive effect on omnichannel use, so it highlights the important role of customer based interface and usefulness. Especially, perceived usefulness has high indirect influence on ease of use and use of omnichannel. It seems that when customers try to decide use or not use omnichannel, customers focus on percept benefits from omnichannel. Thus, a provider should applicate attractive price table, accurate product or service information and high switching cost strategy to emphasize the usefulness of omnichannel. Second, using omnichannel enhances the relationship between customers and brand, because there are more time and frequency to serve customers. It is important because good relationship between customers can increase the future's financial performance through word of mouse, positive brand image and loyalty to brand or company. Finally, despite of empirical result and implications, this study has limitations. First, there are only a few previous studies about omnicahnnel, so literature reviews are restricted. While set up the factors which can affect the use of omnichannel, next study should be considered with broader theories or models(ex: contingency theory). Second, omnichannel has developed from multichannel, so comparative analysis is needed between these methods because there is a possibility about different forte character of each distribution system on customer's consuming patterns.

Modified CTAB DNA Methods for efficient DNA extraction from Rice (Oryza sativa L.) (벼 분자육종을 위한 CTAB DNA 추출 시스템 개량)

  • Lee, Jong-Hee;Kwak, Do-Yeon;Yeo, Un-Sang;Kim, Choon-Song;Jeon, Myeong-Gi;Kang, Jong-Rae;Park, Dong-Soo;Shin, Mun-Sik;Oh, Byeong-Geun;Hwang, Hung-goo
    • Korean Journal of Breeding Science
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    • v.40 no.3
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    • pp.286-290
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    • 2008
  • Many important traits have been tagged allowing plant breeders to apply marker assisted selection (MAS) in rice. PCR itself is simple to set up, and requires little hands-on time. However, a crucial limiting step of MAS programs is the reliable and efficient extraction of DNA which can be performed on thousands of individuals. In this study, We describe a modification of the DNA extraction method, in which cetyltrimethylammonium bromide (CTAB) is used to extract DNA from leaf tissues for suitable MAS in rice. We followed the standard 2% CTAB extraction method in all the procedure. In addition we used the 1.2 ml 8-strip tube instead of 1.5 ml E-tubes to fit the 8-multichannel pipette and employ the 96 well plate to use the swing bucket centrifuge. Our modified CTAB DNA extraction method offers several advantages with respect to traditional and simple methods. 1) adult leaf samples collected in paddy field are applicable. 2) 96 leaf samples can be homogenized only one-time by using tungsten carbonate bead and 96well block. 3) semiautomatic loading method using 8-multichannel pipette from DNA extraction to electrophoresis of PCR products. 4) our system can extract about 400 leaf samples per day by only one technicion. Therefore, this method could be useful for marker assisted breeding in rice.

Cell Interference Analysis and Link Budget for Output Power of Base Station in KOREA Environment of Digital MMDS (디지털 MMDS 방식의 국내환경에서 기지국 송신출력에 따른 링크버짓 및 셀 간섭 분석)

  • Cho, Byung-Lok
    • The KIPS Transactions:PartC
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    • v.9C no.3
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    • pp.439-444
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    • 2002
  • In this paper, we present both the link budget analysis according to system parameters and the cell coverage according to transmitter power and modulation scheme of digital MMDS among the wireless CATV system methods which is bated on the wireless internet service. Also, in this paper, we present C/I and number of subscriber according to splitting cell. In this paper, the cell coverage of which obtain the results according to both transmitter power from 0dBW to -9dBW and modulation scheme of QPSK, 16QAM and 64QAM based on link budget was analysis for system parameter of digital MMDS was able to provide from maximum 134km to minimum 4.3km. Also, in this paper, the number of subscriber of which obtain the results according to polarization wave, frequency of frequency reuse and C/I in 4. 6 and 8 sectors was able to provide from maximum 5,200DSI to minimum 1,300DSI.

The study for electric readout of X-ray signal using MOSFET (MOSFET를 이용한 X선 신호의 전기적 획득에 관한 연구)

  • Park, S.K.;Kang, Y.S.;Seo, J.H.;Park, J.K.;Nam, S.H.
    • Proceedings of the KOSOMBE Conference
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    • v.1998 no.11
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    • pp.295-296
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    • 1998
  • With xeroradiography appearance, DR (Digital Radiography) system have been studying for X-ray detection using photoreceptor. Also detection method for receptor charge change have been developing variably. We use photoreceptor material of a-Se(Amorphous Selenium) with high DQE, high SNR(Signal to Noise Ratio) and high transformation efficiency of X-ray signals into electrical signals. After a-Se receptor is uniformly charged by using Arc discharge, X-ray is exposed. Then a-Se receptor produce subtle charge variation and MOSFET detect charge variations. The detected signal pass A/D converter and signal processing by PC. As results, the initial voltage is 8V. It has wide dynamic range needed digital radiography system. In this study, we obtained data with changing kVp(tube potential voltage) and fixed 8mAs(tube current by exposure time) in X-ray system. However MOSFET detector for X-ray signal is not tested X-ray mAs variations. But if MOSFET detector is tested X-ray mAs variation and exactly calibrated multichannel is made and noise-reduction is done, suitable DR system readout method will be done.

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