• Title/Summary/Keyword: Small-signal

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Development of Proportional Valve Actuator Controller for Industrial Site (산업용 밸브 액추에이터 비례제어 컨트롤러 개발)

  • Park, Han Young;Kim, Jin Young;Ahn, Sung Soo;Kang, Joonhee
    • Journal of the Institute of Electronics and Information Engineers
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    • v.50 no.5
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    • pp.269-274
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    • 2013
  • To proportionally control the electronic valve position of the actuator, we designed and fabricated PCU, CPT, and rotary absolute optical encoder for the detection of absolute angular position in the actuator. We also designed and constructed the test system by using DAQ hardware and Labview. We designed PCU to convert 1-5 V, 0-5 V, 0-10 V, 2-10 V voltage signals and 4-20 mA current signals to the voltage signals in the common 0.5-2.5 V range. We designed CPT to output 4-20 mA current signals corresponding to the valve positions based on the PWM signal input from the MCU. We also designed 20 bit optical encoder by using infrared LED and infrared transistor and made the serial communication with the main board possible. When we tested PCU and CPT with DAQ hardware and Labview software, they operated correctly with the small errors within ${\pm}0.003$ V and ${\pm}0.01$ mA, respectively, showing that our actuator has the excellent performance to employ as the industrial proportional-valve-actuator. The resolution of the encoder was $11.25^{\circ}$ and the maximum revolution to detect was 32,768.

The Transmission of Tele-Information System using BlueTooth (블루투스를 이용한 웹으로의 원격 의료정보 전송 시스템)

  • 채희영;강형원;김영길
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2002.05a
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    • pp.130-133
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    • 2002
  • As a society advances, an aging phenomenon and many diseases which did not exist in old times are happening. Especially, in case of the aged patient, because we cant know the time the condition of the patients health become worse, the study of the Tele-information system has been actively carried out by the necessity of a persistent observation. A ECG signal a kind of a vital signals has been widely used to the medical information system as an usual clinical diagnosis for the patients who possess heart diseases. BlueTooth is a close range wireless communication technology which uses a wireless frequency 2.4GHz and has a high trust and self - error correction technology according to a low power consumption quality and a high-speed frequency hopping. This makes get a high trust concerning a data transmission than an existing modem. In addition, though wireless modem is restricted by a minimal of a wireless terminal, It will be possible to coincide with the function of the portable with the low power consumption quality by using Bluetooth. And as the system on a chip of module progresses, the possibility of the small size is present According to this, Bluetooth module transmits the medical information, which is input from the outside among the operations that use the Bluetooth to the Bluetooth module that is connected the host PC. And the system that the host PC transmits the medical information from the connected Bluetooth module to the Internet has once embedded. this study let the host PC embedded in advance of the existing system and transmit the medical information by the addition of the Tcp/Ip protocol stark under all embedded environments to internet.

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A Variable-Gain Low-Voltage LNA MMIC Based on Control of Feedback Resistance for Wireless LAN Applications (피드백 저항 제어에 의한 무선랜용 가변이득 저전압구동 저잡음 증폭기 MMIC)

  • Kim Keun Hwan;Yoon Kyung Sik;Hwang In Gab
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.29 no.10A
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    • pp.1223-1229
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    • 2004
  • A variable-gain low-voltage low noise amplifier MMIC operating at 5GHz frequency band is designed and implemented using the ETRI 0.5$\mu\textrm{m}$ GaAs MESFET library process. This low noise amplifier is designed to have the variable gain for adaptive antenna array combined in HIPERLAN/2. The feedback circuit of a resistor and channel resistance controlled by the gate voltage of enhancement MESFET is proposed for the variable-gain low noise amplifier consisted of cascaded two stages. The fabricated variable gain amplifier exhibits 5.5GHz center frequency, 14.7dB small signal gain, 10.6dB input return loss, 10.7dB output return loss, 14.4dB variable gain, and 2.98dB noise figure at V$\_$DD/=1.5V, V$\_$GGl/=0.4V, and V$\_$GG2/=0.5V. This low noise amplifier also shows-19.7dBm input PldB, -10dBm IIP3, 52.6dB SFDR, and 9.5mW power consumption.

An Enhanced DESYNC Scheme for Simple TDMA Systems in Single-Hop Wireless Ad-Hoc Networks (단일홉 무선 애드혹 네트워크에서 단순 TDMA 시스템을 위한 DESYNC 알고리즘 개선 방안)

  • Hyun, Sanghyun;Lee, Jeyul;Yang, Dongmin
    • KIPS Transactions on Computer and Communication Systems
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    • v.3 no.9
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    • pp.293-300
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    • 2014
  • TDMA(Time Division Multiple Access) is a channel access scheme for shared medium networks. The shared frequency is divided into multiple time slots, some of which are assigned to a user for communication. Techniques for TDMA can be categorized into two classes: synchronous and asynchronous. Synchronization is not suitable for small scale networks because it is complicated and requires additional equipments. In contrast, in DESYNC, a biologically-inspired algorithm, the synchronization can be easily achieved without a global clock or other infrastructure overhead. However, DESYNC spends a great deal of time to complete synchronization and does not guarantee the maximum time to synch completion. In this paper, we propose a lightweight synchronization scheme, C-DESYNC, which counts the number of participating nodes with GP (Global Packet) signal including the information about the starting time of a period. The proposed algorithm is mush simpler than the existing synchronization TDMA techniques in terms of cost-effective method and guarantees the maximum time to synch completion. Our simulation results show that C-DESYNC guarantees the completion of the synchronization process within only 3 periods regardless of the number of nodes.

UA Tree-based Reduction of Speech DB in a Large Corpus-based Korean TTS (대용량 한국어 TTS의 결정트리기반 음성 DB 감축 방안)

  • Lee, Jung-Chul
    • Journal of the Korea Society of Computer and Information
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    • v.15 no.7
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    • pp.91-98
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    • 2010
  • Large corpus-based concatenating Text-to-Speech (TTS) systems can generate natural synthetic speech without additional signal processing. Because the improvements in the natualness, personality, speaking style, emotions of synthetic speech need the increase of the size of speech DB, it is necessary to prune the redundant speech segments in a large speech segment DB. In this paper, we propose a new method to construct a segmental speech DB for the Korean TTS system based on a clustering algorithm to downsize the segmental speech DB. For the performance test, the synthetic speech was generated using the Korean TTS system which consists of the language processing module, prosody processing module, segment selection module, speech concatenation module, and segmental speech DB. And MOS test was executed with the a set of synthetic speech generated with 4 different segmental speech DBs. We constructed 4 different segmental speech DB by combining CM1(or CM2) tree clustering method and full DB (or reduced DB). Experimental results show that the proposed method can reduce the size of speech DB by 23% and get high MOS in the perception test. Therefore the proposed method can be applied to make a small sized TTS.

A Study on Motion Estimator Design Using DCT DC Value (DCT 직류 값을 이용한 움직임 추정기 설계에 관한 연구)

  • Lee, Gwon-Cheol;Park, Jong-Jin;Jo, Won-Gyeong
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.38 no.3
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    • pp.258-268
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    • 2001
  • The compression method is necessarily used to send the high quality moving picture that contains a number of data in image processing. In the field of moving picture compression method, the motion estimation algorithm is used to reduce the temporal redundancy. Block matching algorithm to be usually used is distinguished partial search algorithm with full search algorithm. Full search algorithm be used in this paper is the method to compare the reference block with entire block in the search window. It is very efficient and has simple data flow and control circuit. But the bigger the search window, the larger hardware size, because large computational operation is needed. In this paper, we design the full search block matching motion estimator. Using the DCT DC values, we decide luminance. And we apply 3 bit compare-selector using bit plane to I(Intra coded) picture, not using 8 bit luminance signals. Also it is suggested that use the same selective bit for the P(Predicted coded) and B(Bidirectional coded) picture. We compare based full search method with PSNR(Peak Signal to Noise Ratio) for C language modeling. Its condition is the reference block 8$\times$8, the search window 24$\times$24 and 352$\times$288 gray scale standard video images. The result has small difference that we cannot see. And we design the suggested motion estimator that hardware size is proved to reduce 38.3% for structure I and 30.7% for structure II. The memory is proved to reduce 31.3% for structure I and II.

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Effects of Joint Mobilization Techniques on the Joint Receptors (관절 가동운동이 관절 감수기에 미치는 영향)

  • Kim, Suhn-Yeop
    • The Journal of Korean Academy of Orthopedic Manual Physical Therapy
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    • v.2 no.1
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    • pp.9-19
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    • 1996
  • Type I, II, III are regarded as "true" joint receptors, type IV is considered a class of pain receptor. Type I, II and III mechanoreceptors, via static and dynamic input, signal joint position, intraarticular pressure changes, and the direction, amplitude, and velocity of joint movements. Type I mechanoreceptor subserve both static and dynamic physiologic functions. Type I are found primarily in the stratum fibrosum of the joint capsule and ligaments. Type I receptors have a low threshold for activation and are allow to adapt to changes altering their firing frequency. Type II receptors have a low threshold for activation. These dynamic receptors respond to joint movement. Type II receptors are thus termed rapidly adapting. Type II joint receptors are located at the junction of the synovial membrane and fibrosum of the joint capsule and intraarticular and extraarticular fat pads. Type III receptors have been found in collateral ligaments of the joints of the extremities. Morphologically similar to Golgi tendon organ. These dynamic receptors have a high threshold to stimulation and are slowly adating. Type IV receptors possess free nerve ending that have been found in joint capsule and fat pads. They are not normally active, but respond to extreme mechanical deformation of the joint as well as to direct chemical or mechanical irritation. Small amplitude oscillatory and distraction movements(joint mobilization) techniques are used to stimulate the mechanoreceptors that may inhibit the transmission of nociceptors stimuli at the spinal cord or brain stem levels.

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Digital Modulation Types Recognition using HOS and WT in Multipath Fading Environments (다중경로 페이딩 환경에서 HOS와 WT을 이용한 디지털 변조형태 인식)

  • Park, Cheol-Sun
    • Journal of the Institute of Electronics Engineers of Korea CI
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    • v.45 no.5
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    • pp.102-109
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    • 2008
  • In this paper, the robust hybrid modulation type classifier which use both HOS and WT key features and can recognize 10 digitally modulated signals without a priori information in multipath fading channel conditions is proposed. The proposed classifier developed using data taken field measurements in various propagation model (i,e., rural area, small town and urban area) for real world scenarios. The 9 channel data are used for supervised training and the 6 channel data are used for testing among total 15 channel data(i.e., holdout-like method). The Proposed classifier is based on HOS key features because they are relatively robust to signal distortion in AWGN and multipath environments, and combined WT key features for classifying MQAM(M=16, 64, 256) signals which are difficult to classify without equalization scheme such as AMA(Alphabet Matched Algorithm) or MMA(Multi-modulus Algorithm. To investigate the performance of proposed classifier, these selected key features are applied in SVM(Support Vector Machine) which is known to having good capability of classifying because of mapping input space to hyperspace for margin maximization. The Pcc(Probability of correct classification) of the proposed classifier shows higher than those of classifiers using only HOS or WT key features in both training channels and testing channels. Especially, the Pccs of MQAM 3re almost perfect in various SNR levels.

Signal Treatement for Topex/Poseidon Satellite Altimetric Data and Its Application near the Korean Seas (Topex/Poseidon위성 고도계 자료에 대한 신호처리 및 한반도 주변해역에 대한 그 적용)

  • Yoon, Hong-Joo
    • Journal of the Korean Association of Geographic Information Studies
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    • v.2 no.1
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    • pp.12-31
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    • 1999
  • Topex/Poseidon satellite altimetric data are used to estimate characteristics on the oceanic and atmospheric correction factors, and the mean sea level and its variations in the Yellow Sea, the East China Sea and the East Sea from September 1992 through August 1994(70cycles). For the atmospheric correction factors, the variations of dry troposphere, humid troposphere, ionosphere and inverted barometer were very small as a few centimeters, but the variations of electromagnetic bias were higher than other factors. For the oceanic correction factors, the variations of ocean tide(35cm in track 127 and 60cm in track 214) showed high ranges compared to elastic tide(5cm in track 127 and 1cm in track 214) and loading tide(1.8cm in track 127 and 1cm in track 214). It should be understood that the variations of ocean free surface is mainly under the influence of, firstly, ocean tide and, secondly, electromagnetic bias. Mean sea level in the Yellow Sea are higher than in the rest of Seas. Then its range generally comprised between -60cm and 210cm with mean value of about 100cm. Also its variations showed high values in the Yellow Sea and East China Sea, especially 5.689cm in Youngampo. This result is mainly due to the effects of local topography and tidal current.

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An Electromagnetic Shock Wave Generator Employing a Solenoid Coil for Extracorporeal Shock Wave Therapy: Construction and Acoustical Properties (체외 충격파 치료술을 위한 솔레노이드 코일을 이용한 전자기식 충격파 발생기: 구성 및 음향학적 특성)

  • Choi Min Joo;Lee Jong Soo;Kang Gwan Suk;Paeng Dong Guk;Lee Yoon Joon;Cho Chu Hyun;Rim Geun Hie
    • The Journal of the Acoustical Society of Korea
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    • v.24 no.5
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    • pp.271-281
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    • 2005
  • An electromagnetic type shock wave generator suitable for extracorporeal shock wave therapy has been constructed by employing a solenoid coil. The Property of the shock waves produced by the shock wave generator was evaluated using a needle hydrophone. It was shown that, as the capacitor discharging voltage increased from 8 to 18 kV, the Positive Peak Pressure (P+) of the shock wave increased non-linearly from 10 to 77 Wa. In contrast. the negative peak Pressure (f) varied between -3.2 and -6.8 MPa. had its absolute maximum of -6.9 ma at 14 kV The peak amplitudes P+ measured repeatedly under the same voltage setting varied within $5\;\%$ from mean values and this is very small compared to about $50\;\%$ for electrohydraulic type shock wave generators. It could be observed, from the hydrophone signal recorded over 1 ms. several sequential acoustic impulses representing bubble collapses. namely. acoustic cavitation. induced by the shock wave. A technique based on wavelet transformation was used to accurately measure the time delay between the 1st and 2nd collapse known to be closely related to the shock strength. It was observed that the measured time delay increased almost linearly from 120 to $700\;{\mu}s$ with the shock wave Pressure P+ increasing from 10 to 77 MPa.