• Title/Summary/Keyword: Single domain

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SC-FDE System Using Decision-Directed Method Over Time-Variant Fading Channels (시변 페이딩 채널에 대한 결정 지향 방식의 SC-FDE 시스템)

  • Kim, Ji-Heon;Yang, Jin-Mo;Kim, Whan-Woo
    • The Journal of the Acoustical Society of Korea
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    • v.26 no.6
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    • pp.227-234
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    • 2007
  • This paper describes a transmission method based on a single carrier with frequency domain equalization (SC-FDE) scheme with cyclic prefix(CP). The SC-FDE has similar features with orthogonal frequency division multiplexing(OFDM). Similar to OFDM, a SC-FDE system is computationally efficient since equalization is reformed on a block of data in the frequency domain. Especially, it has the advantage of low sensitivity to nonlinear distortion compared to OFDM. In this paper, we design a SC-FDE receiver using decision-directed method, and present simulation results.

Frequency Domain Encoding Matrices for Computationally Efficient STBC/SFBC OFDM Transmitters (복잡도 감소를 위한 MIMO-STBC/SFBC OFDM 방식의 주파수 도메인 부호화 행렬)

  • Cho, Se-Young;Shang, Pingping;Kim, Soo-Young;Lim, Kwang-Jae
    • Journal of the Institute of Electronics Engineers of Korea TC
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    • v.47 no.12
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    • pp.8-16
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    • 2010
  • In this paper, we present a structure of computationally efficient MIMO-OFDM transmitters, using STBC. Straightforward implementation of these systems requires separate WFT processing blocks for each of the transmit antennas. In our proposed scheme, we use symmetry properties of Fourier transform, and thus use a frequency domain encoding strategy. This greatly reduces the computational burden. The proposed scheme uses just a single IFFT block at each OFDM symbol period, and thus resulting in the same complexity as a single antenna OFDM system. As specific examples of the proposed schemes, we present frequency domain encoding matrices for QO-STBC-OFDM and QO-SFBC-OFDM transmitters.

Micro-defects in $LiNbO_3$ single crystals with congruent melting composition (조화용융성조성을 가진 $LiNbO_3$ 단결성의 미소결함)

  • 김현기;권달회;이선우;심광보;오근호
    • Journal of the Korean Crystal Growth and Crystal Technology
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    • v.9 no.3
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    • pp.267-272
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    • 1999
  • Micro-defects in the undoped and MgO-doped $LiNbO_3$ single crystals, which were grown from a congruent melting composition (48.6 mol% $Li_2$O) by the CZ (Czochralski) method, were analyzed using microscopic techniques such as optical microscopy (OM), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Effects of the dopant and g value (the fraction solidfied) on the domain structure and micro-defect were investigated to build a corelationship with a growth condition of crystal. It was observed that the micro-defect concentrated near the domain wall is caused by high stress. Especially, the micro-defect was observed to be biased toward a certain side of the domain wall.

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Dynamic 3D Worker Pose Registration for Safety Monitoring in Manufacturing Environment based on Multi-domain Vision System (다중 도메인 비전 시스템 기반 제조 환경 안전 모니터링을 위한 동적 3D 작업자 자세 정합 기법)

  • Ji Dong Choi;Min Young Kim;Byeong Hak Kim
    • IEMEK Journal of Embedded Systems and Applications
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    • v.18 no.6
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    • pp.303-310
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    • 2023
  • A single vision system limits the ability to accurately understand the spatial constraints and interactions between robots and dynamic workers caused by gantry robots and collaborative robots during production manufacturing. In this paper, we propose a 3D pose registration method for dynamic workers based on a multi-domain vision system for safety monitoring in manufacturing environments. This method uses OpenPose, a deep learning-based posture estimation model, to estimate the worker's dynamic two-dimensional posture in real-time and reconstruct it into three-dimensional coordinates. The 3D coordinates of the reconstructed multi-domain vision system were aligned using the ICP algorithm and then registered to a single 3D coordinate system. The proposed method showed effective performance in a manufacturing process environment with an average registration error of 0.0664 m and an average frame rate of 14.597 per second.

Development of Programmable Automation Controllers (PACs) having Multi-Domain Functionality (다양한 도메인 기능을 갖는 PAC 시스템 개발)

  • Kim K.D.;Lee K.J.;Kim H.N.;Oh J.S.;Kim C.B.
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2005.06a
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    • pp.250-253
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    • 2005
  • A Programmable Automation Controller (PAC) has been developed by Turbotek Co., Ltd. The developed system has multi-domain functionality-including sequence control, motion control and HMI- on a single platform. The PAC also has a common development platform for the design and integration of multi-domain automated systems. Since hardware of the developed system has modular architectures, performance and specification of the controller are determined by combination of specific modules. The developed system employs de facto standards such as OPC interface that allow users to easily exchange data as part of networked multi-vendor systems.

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On Narrowband Interference Suppression in OFDM-based Systems with CDMA and Weighted-type Fractional Fourier Transform Domain Preprocessing

  • Liang, Yuan;Da, Xinyu;Wang, Shu
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.11 no.11
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    • pp.5377-5391
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    • 2017
  • In this paper, we propose a new scheme to suppress the narrowband interference (NBI) in OFDM-based systems. The scheme utilizes code division multiple access (CDMA) and weighted-type fractional Fourier transform (WFRFT) domain preprocessing technologies. Through setting the WFRFT order, the scheme can switch into a single carrier (SC) or a multi-carrier (MC) frequency division multiple access block transmission system. The residual NBI can be eliminated to the maximum extent when the WFRFT order is selected properly. Final simulation results show that the proposed system can outperform MC and SC with CDMA and frequency domain preprocessing in terms of the narrowband interference suppression.

Identification and Expression Patterns of kif3bz during the Zebrafish Embryonic Development

  • Lee, A-Ram;Rhee, Myung-Chull
    • Animal cells and systems
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    • v.13 no.4
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    • pp.411-418
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    • 2009
  • We are reporting the identification, expression patterns, and possible biological functions of zebrafish kif3b (kif3bz) encoding 475 amino acids. Kif3Bz contains the kinesin motor domain, catalytic domain, KISc domain, and one single coiled coil domain. Phylogenetic analysis indicates that kif3bz is a highly conserved gene among the tested vertebrates. First of all, both maternal and zygotic messages of kif3bz were evenly distributed in the blastomeres at 2-cell stage. Its ubiquitous expression throughout the blastomeres continued till 40% epiboly. However, kif3bz transcripts became restricted in Kupffer's vesicle at tailbud and 6-somite stages. At 13-somite stage, kif3bz expression pattern became specific to the telencephalon, diencephalon, trigeminal placode, and somites. Such expression patterns were further intensified in the telencephalon, diencephalons, hind brain, pronephric ducts, optic vesicles, and spinal cord neurons in the 23-somite stage embryos, and last till 24 hpf. We discussed possible functions of Kif3Bz related to the vertebrate embryonic development.

A Novel Log-Domain First-Order Multifunction Filter

  • Kircay, Ali;Cam, Ugur
    • ETRI Journal
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    • v.28 no.3
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    • pp.401-404
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    • 2006
  • A new log-domain first-order multifunction filter is proposed in this letter. The proposed filter is systematically derived using the state-space synthesis procedure from a corresponding block diagram. It provides low-pass (LP), high-pass (HP), and all-pass (AP) responses simultaneously for a single input signal. The filter circuit has a very simple structure since it uses only bipolar junction transistors (BJTs) and a grounded capacitor. It can be electronically tuned by changing an external current. The filter has a greater bandwidth due to its inherent current-mode and log-domain operations. PSPICE simulations are given to confirm the theoretical analysis.

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Scanning Nonlinear Dielectric Microscopy : Overview -A High Resolution Tool for Observing Ferroelectric Domains and Nano-domain Engineering-

  • Cho, Yasuo
    • Journal of the Korean Ceramic Society
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    • v.40 no.11
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    • pp.1047-1057
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    • 2003
  • A sub-nanometer resolution Scanning Nonlinear Dielectric Microscope (SNDM) was developed for observing ferroelectric polarization. We also demonstrate that the resolution of SNDM is higher than that of a conventional piezo-response imaging. Secondly, we report new SNDM technique detecting higher nonlinear dielectric constants $\varepsilon$$\_$3333/ and $\varepsilon$$\_$33333/. Higher order nonlinear dielectric imaging provides higher lateral and depth resolution. Finally, the formation of artificial small inverted domain is reported to demonstrate that SNDM system is very useful as a nano-domain engineering tool. The nano-size domain dots were successfully formed in LiTaO$_3$ single crystal. This means that we can obtain a very high density ferroelectric data storage with the density above 1T-bits/inch$^2$.

Nanomolding of High Density Patterned Media and Measurement of Magnetic Domain (고밀도 패턴드 미디어 성형 및 자성 도메인 평가에 관한 연구)

  • Yang, J.M.;Lee, N.S.;Kang, S.
    • Proceedings of the Korean Society for Technology of Plasticity Conference
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    • 2008.05a
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    • pp.305-308
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    • 2008
  • In this paper, the magnetic domain states and recordability of the molded magnetic nanopillars were examined and analyzed by magnetic force microscopy (MFM) measurement. We focused on the some of the technical issues for MFM measurement regarding the lift height and geometry of the MFM tip. The effects of MFM tip shape and lift height on the MFM resolution were analyzed. Finally, we showed that the magnetic film on each molded nanopillars has a single magnetic domain state.

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