• 제목/요약/키워드: single-channel

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Effect of Acupuncture(PC6) on Behavior, Dopamine Release in the Nucleus Accumbens in Rats Sensitized to Morphine (몰핀에 민감화된 흰쥐의 내관부위 자침이 행동과 측핵의 도파민 유리에 미치는 효과)

  • Kim, Sang-Ho;Lyu, Seung-Jun;Kim, Tae-Heon;Kang, Hyung-Won;Lyu, Yeoung-Su
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.19 no.4
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    • pp.982-992
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    • 2005
  • Acupuncture as a therapeutic intervention is widely used for the treatment of many functional disorders such as substance abuse and mental dysfunction. Clinical trials are currently underway to determine the effectiveness of acupuncture in the treatment of drug addiction. Yet, there are still many unanswered questions about the basic mechanism of acupuncture. Studies have shown that both the psychomotor stimulant effects and rewarding properties of addictive drugs, including morphine, are sensitized by repeated drug administration and raised the possibility that both of these effects may De linked to the same or closely overlapping the mesolimbic dopamine systems. Neiguan (PC6) point on the pericardium channel which is associated with the brain and its mental function, has been used to treat mental, psychosomatic disorders and gastroenterological disorders. The present study was designed to investigate the effect of acupuncture on repeated morphine-induced changes in extracellular dopamine levels using in vivo microdialysis and to measure the effect of acupuncture on repeated morphine-induced behavioral changes. Male Sprague-Dawley rats were treated twice a day for three days with increasing doses of morphine (10, 20 and 40 mg/kg, s.c.) or with saline. After 15 days of withdrawal, rats were challenged with morphine hydrochloride (5 mg/kg, s.c.). Acupuncture was applied at bilateral Neiguan (PC6) points for 1min after the morphine challenge. Results showed that acupuncture at the specific acupoint PC6, but not at control points (tail and HE8) significantly decreased both dopamine release, behavior induced by a systemic morphine challenge or a single s.c. morphine injection in the morphine-repeated animals. These results suggest that reduction in sensitization may be one mechanism whereby acupuncture alleviates morphine craving in addicts. Moreover, in a more general sense these results suggest that acupuncture can be used as a therapeutic intervention for correcting reversible malfunction of the body by direction of brain pathway and thus acupuncture can contribute to the biochemical balance in the central nervous system by regulating neurotransmitters.

An Experimental Study on Tip Velocity and Downstream Recirculation Zone of Single Groyne Conditions (단일 횡수제 조건에 따른 선단부 유속과 재순환 영역에 대한 실험 연구)

  • Kang, Joon-Gu;Yeo, Hong-Koo;Kim, Sung-Jung
    • Journal of Korea Water Resources Association
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    • v.38 no.2
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    • pp.143-153
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    • 2005
  • Recently, the concern of groynes that provide us with various ecological environment and improvement of scenary near river as well as hydraulic improvement has greatly increased for naturalized river and ecological river restoration. However there is no adequate design guidelines in Korea. Furthermore there is lack of research for installation of groynes in Korea. Thus, in this study, we have conducted hydraulic modeling test for kinds of groyne and changes of permeability and made a study of the analysis for installation factor of groyne. Experimental conditions were the fixed bed model for flow pattern of groyne tip and separation length about changes of groyne length and permeability. The Experiments were conducted to measure velocity and drift angle at groyne tip. The main study kas measured the groyne tip velocity for a factor of scour and drift angle for velocity increase at center of channel. We have suggested the equation about groyne tip velocity rate(tip velocity/ approach velocity) and area rate(groyne area/ flow area). And In recirculation zone of groyne downstream, To study the basic data of groyne about installation interval has analyzed the change of separation length and incidence angle. We have suggested the equation about separation length rate(separation length/ groyne length), changes of permeability and installation angle.

Geophysical Imaging of Alluvial Water Table and the underlying Layers of Weathered and Soft Rocks (충적층 지하수면 및 그 하부의 풍화암/연암의 경계면 파악을 위한 복합 지구물리탐사)

  • Ju, Hyeon-Tae;Lee, Chul-Hee;Kim, Ji-Soo
    • The Journal of Engineering Geology
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    • v.25 no.3
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    • pp.349-356
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    • 2015
  • Although geophysical methods are useful and generally provide valuable information about the subsurface, it is important to recognize their limitations. A common limitation is the lack of sufficient contrast in physical properties between different layers. Thus, multiple methods are commonly used to best constrain the physical properties of different layers and interpret each section individually. Ground penetrating radar (GPR) and shallow seismic reflection (SSR) methods, used for shallow and very shallow subsurface imaging, respond to dielectric and velocity contrasts between layers, respectively. In this study, we merged GPR and SSR data from a test site within the Cheongui granitic mass, where the water table is ~3 m deep all year. We interpreted the data in combination with field observations and existing data from drill cores and well logs. GPR and SSR reflections from the tops of the sand layer, water table, and weathered and soft rocks are successfully mapped in a single section, and they correlate well with electrical resistivity data and SPS (suspension PS) well-logging profiles. In addition, subsurface interfaces in the integrated section correlate well with S-wave velocity structures from multi-channel analysis shear wave (MASW) data, a method that was recently developed to enhance lateral resolution on the basis of CMP (common midpoint) cross-correlation (CMPCC) analysis.

Reliability improvement of an ion-measuring system using FET sensor array (FET 센서 어레이를 이용한 이온 측정 시스템의 신뢰도 개선)

  • Choi, Jung-Tae;Lee, Seung-Hyup;Kim, Young-Jin;Lee, Young-Chul;Cho, Byung-Woog;Sohn, Byung-Ki
    • Journal of Sensor Science and Technology
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    • v.8 no.4
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    • pp.341-346
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    • 1999
  • In general cases, compared with glass electrode, FET type electrolyte sensors have many advantages. But the drift, memory effect and the poor reproducibility of the FET type electrolyte sensor cause the decrease of the reliability in the measurement system. To improve the reliability, an ion-measuring system using FET type electrolyte sensor array with 8 sensors has been developed. Developed system employed the electronic switchs to connect a signal detecting circuit with 8 sensor array and the system can measure ion concentration of 4 different type electrolyte($H^+$, $Na^+$, $K^+$, $Ca^{2+}$). The signal processing algorithm with insertion sorting method was adopted to enhance the reliability. We measured 3 different ion($H^+$, $Na^+$, $K^+$) to evaluate the performance of developed system. The results show that the designed signal processing algorithm can reduce the error range in comparison with a simple arithmetic mean and the developed system has a good reliability over the previous single channel sensor system.

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Association Study Between Polymorphisms of Inositol 1,4,5-triphosphate Receptor Type 1 (IP3R1) Gene and Carcass Traits in Korean Cattle (Hanwoo) (한우 Inositol 1,4,5-triphosphate Receptor Type 1 (IP3R1) 유전자의 다형성 및 형질 관련성 분석)

  • Kim, Nam-Kuk;Kim, Geon-Seok;Jung, Yu-Sung;Moon, Hee-Joo;Cho, Yong-Min;Yoon, Du-Hak
    • Journal of Animal Science and Technology
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    • v.51 no.4
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    • pp.289-294
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    • 2009
  • Inositol 1,4,5-triphosphate receptor type 1 (IP3R1) is a $Ca^{2+}$ release channel that responds to the second messenger IP3 and that modulates diverse cellular functions such as contraction/excitation, secretion, gene expression and cellular growth. We discovered single nucleotide polymorphisms (SNPs) within IP3R1 gene and analyzed associations between gene polymorphisms and carcass traits in Korean cattle (Hanwoo) in order to develop novel DNA markers at genomic level. Three SNPs were detected at the position of g.1428617A>G, g.1418843C>T and g.1414377C>T with 24 unrelated Hanwoo samples by direct sequencing of the PCR products. We found that genotype of g.1414377C>T SNP was associated with live weight (P<0.05) and carcass weight (P<0.01) using the general linear model of SAS package. These results suggest that polymorphism of IP3R1 gene was associated with weight-related traits in Hanwoo.

Multirate Multicarrier DS/CDMA with 2-Domain Spreading (2차원 확산을 사용하는 다중전송률 MC-DS/CDMA 시스템)

  • Kim, Nam-Sun
    • Journal of Korea Society of Industrial Information Systems
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    • v.16 no.4
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    • pp.27-35
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    • 2011
  • Multicarrier-Direct Sequence/Code Division Multiple Access(MC-DS/ CDMA) which is a combination of Orthogonal Frequency Division Multiplexing(OFDM) and DS/CDMA has been of significant interest as a means to take such advantages as bandwidth efficiency, high bit rate and robustness against multipath fading. In this paper we study a reduced-complexity multiuser detection aided multirate MC-DS/CDMA with time(T)-domain and frequency(F)-domain spreading. The one- dimensional orthogonal variable spreading factor(1D OVSF) code extracted from 2D OVSF code are used as a spreading code in T/F-domain. The proposed system will use code grouping interference cancellation(CGIC) receiver to reduce Multiuser Interference(MUI). The CGIC receiver uses code grouping by the correlation properties of 1D OVSF code and dose not requires the code information and activity of other user. The multiuser detector with CGIC receiver will be analyzed in Time- and Frequency-domain separately(jointly). The system performance is analytically derived in Additive White Gaussian Noise(AWGN) channel and we also compare the system performance between proposed system and T/F spreaded single(multi) rate multiuser MC-DS/CDMA system. In the computer simulation results, the proposed receiver of demonstrated huge performance improvement over conventional matched filter receiver.

Frame Synchronization Algorithm based on Differential Correlation for Burst OFDM System (Burst OFDM 시스템을 위한 차동 상관 기반의 프레임 동기 알고리즘)

  • Um Jung-Sun;Do Joo-Hyun;Kim Min-Gu;Choi Hyung-Jin
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.30 no.10C
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    • pp.1017-1026
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    • 2005
  • In burst OFDM system, the frame synchronization should be performed first for the acquisition of received frame and the estimation of the correct FFT-window position. The conventional frame synchronization algorithms using design features of the preamble symbol, the repetition pattern of the OFDM symbol by pilot sub-carrier allocation rule and Cyclic Prefix(CP), has difficulty in the detection of precise frame timing because its correlation characteristics would increase and decrease gradually. Also, the algorithm based on the correlation between the reference signal and the received signal has performance degradation due to frequency offset. Therefore, we adopt a differential correlation method that is robust to frequency offset and has the clear peak value at the correct frame timing for frame synchronization. However, performance improvement is essential for differential correlation methods, since it usually shows multiple peak values due to the repetition pattern. In this paper, we propose an enhanced frame synchronization algorithm based on the differential correlation method that shows a clear single peak value by using differential correlation between samples of identical repeating pattern. We also introduce a normalization scheme which normalizes the result of differential correlation with signal power to reduce the frame timing error in the high speed mobile channel environments.

An Asynchronous UWB Positioning Scheme with Low Complexity and Low Power Consumption (낮은 복잡도와 전력 소모의 비동기식 UWB 무선측위 기법)

  • Kim, Jae-Woon;Park, Young-Jin;Lee, Soon-Woo;Shin, Yo-An
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.34 no.11C
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    • pp.1098-1105
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    • 2009
  • In this paper, we propose an asynchronous UWB (Ultra Wide Band) Positioning scheme that can provide precise positioning performance with low complexity and low power consumption. We also present the residual test to improve the positioning performance in multipath channels having heavy NLoS (Non-Line of Sight) components. As compared to conventional ToA (Time of Arrival) positioning scheme that requires round-trip transmissions as many as the number of beacons, the proposed UWB positioning scheme effectively decrease power consumption and processing delay since a single round-trip transmission is only required. Also, as compared to conventional TDoA (Time Difference of Arrival) positioning scheme requiring precise synchronization among the beacons, asynchronous nature of the proposed scheme achieves very low system complexity. Through simulations in LoS (Line of Sight) channel models, we observe that the proposed scheme requires low system complexity, low power consumption, while providing positioning performance of almost the same accuracy as the conventional ToA and TDoA positioning schemes. In addition, the proposed scheme by employing the residual test achieves accurate positioning performance even in multipath channels having heavy NLoS components.

GaN HEMT Based High Power and High Efficiency Doherty Amplifiers with Digital Pre-Distortion Correction for WiBro Applications

  • Park, Jun-Chul;Kim, Dong-Su;Yoo, Chan-Sei;Lee, Woo-Sung;Yook, Jong-Gwan;Chun, Sang-Hyun;Kim, Jong-Heon;Hahn, Cheol-Koo
    • Journal of electromagnetic engineering and science
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    • v.11 no.1
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    • pp.16-26
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    • 2011
  • This paper presents high power and high efficiency Doherty amplifiers for 2.345 GHz wireless broadband (WiBro) applications that use a Nitronex 125-W ($P_{3dB}$) GaN high electron mobility transistor (HEMT). Two- and three-way Doherty amplifiers and a saturated Doherty amplifier using Class-F circuitry are implemented. The measured result for a center frequency of 2.345 GHz shows that the two-way Doherty amplifier attains a high $P_{3dB}$ of 51.5 dBm, a gain of 12.5 dB, and a power-added efficiency (PAE) improvement of about 16 % compared to a single class AB amplifier at 6-dB back-off power region from $P_{3dB}$. For a WiBro OFDMA signal, the Doherty amplifier provides an adjacent channel leakage ratio (ACLR) at 4.77 MHz offset that is -33 dBc at an output power of 42 dBm, which is a 9.5 dB back-off power region from $P_{3dB}$. By employing a digital pre-distortion (DPD) technique, the ACLR of the Doherty amplifier is improved from -33 dBc to -48 dBc. The measured result for the same frequency shows that the three-way Doherty amplifier, which has a $P_{3dB}$ of 53.16 dBm and a gain of 10.3 dB, and the saturated Doherty amplifier, which has a $P_{3dB}$ of 51.1 dBm and a gain of 10.3 dB, provide a PAE improvement of 11 % at the 9-dB back-off power region and 7.5 % at the 6-dB back-off region, respectively, compared to the two-way Doherty amplifier.

Design of 77 GHz Automotive Radar System (77 GHz 차량용 레이더 시스템 설계)

  • Nam, Hyeong-Ki;Kang, Hyun-Sang;Song, Ui-Jong;Cui, Chenglin;Kim, Seong-Kyun;Nam, Sang-Wook;Kim, Byung-Sung
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.24 no.9
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    • pp.936-943
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    • 2013
  • This work presents the design and measured results of the single channel automotive radar system for 76.5~77 GHz long range FMCW radar applications. The transmitter uses a commercial GaAs monolithic microwave integrated circuit(MMIC) and the receiver uses the down converter designed using 65 nm CMOS process. The output power of the transmitter is 10 dBm. The down converter chip can operate at low LO power as -8 dBm which is easily supplied from the transmitter output using a coupled line coupler. All MMICs are mounted on an aluminum jig which embeds the WR-10 waveguide. A microstrip to waveguide transition is designed to feed the embedded waveguide and finally high gain horn antennas. The overall size of the fabricated radar system is $80mm{\times}61mm{\times}21mm$. The radar system achieved an output power of 10 dBm, phase noise of -94 dBc/Hz at 1 MHz offset and a conversion gain of 12 dB.