• 제목/요약/키워드: Block Division

검색결과 917건 처리시간 0.03초

완전탐색에 의한 움직임 추정기 시스토릭 어레이 구조 (Systolic arry archtecture for full-search mothion estimation)

  • 백종섭;남승현;이문기
    • 전자공학회논문지B
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    • 제31B권12호
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    • pp.27-34
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    • 1994
  • Block matching motion estimation is the most widely used method for motion compensated coding of image sequences. Based on a two dimensional systolic array, VLSI architecture and implementation of the full search block matching algorithm are described in this paper. The proposed architecture improves conventional array architecture by designing efficient processing elements that can control the data prodeuced by efficient search window division method. The advantages are that 1) it allows serial input to reduce pin counts for efficient composition of local memories but performs parallel processing. 2) It is flexible and can adjust to dimensional changes of search windows with simple control logic. 3) It has no idel time during the operation. 4) It can operate in real/time for low and main level in MPEG-2 standard. 5) It has modular and regular structure and thus is sutiable for VLSI implementation.

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Decision Feedback Detector for Space-Time Block Codes over Time-Varying Channels

  • Ahn, Kyung-Seung;Baik, Heung-Ki
    • 한국통신학회논문지
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    • 제28권5C호
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    • pp.506-513
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    • 2003
  • Most existing space-time coding (STC) schemes have been developed for flat fading channels. To obtain antenna diversity gain, they rely on channel state information (CSI) required at the receiver through channel estimation techniques. This paper proposes a new decision feedback decoding scheme for Alamouti-based space-time block coding (STBC) transmission over time-selective fading channels. In wireless channels, time-selective fading effects arise mainly due to Doppler shift and carrier frequency offset, Modelling the time-selective fading channels as the first-order Gauss-Markov processes, we use recursive algorithms such as Kalman filtering, LMS and RLS algorithms for channel tracking. The proposed scheme consists of the symbol decoding stage and channel tracking algorithms. Computer simulations confirm that the proposed scheme shows the better performance and robustness to time-selectivity.

Motion-Compensated Frame Interpolation Using a Parabolic Motion Model and Adaptive Motion Vector Selection

  • Choi, Kang-Sun;Hwang, Min-Chul
    • ETRI Journal
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    • 제33권2호
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    • pp.295-298
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    • 2011
  • We propose a motion-compensated frame interpolation method in which an accurate backward/forward motion vector pair (MVP) is estimated based on a parabolic motion model. A reliability measure for an MVP is also proposed to select the most reliable MVP for each interpolated block. The possibility of deformation of bidirectional corresponding blocks is estimated from the selected MVP. Then, each interpolated block is produced by combining corresponding blocks with the weights based on the possibility of deformation. Experimental results show that the proposed method improves PSNR performance by up to 2.8 dB as compared to conventional methods and achieves higher visual quality without annoying blockiness artifacts.

A Study on Complexity Reduction for Space-Time Block Codes Decoder in MIMO OFDM systems

  • Pham, Van-Su;Le, Minh-Tuan;Mai, Linh;Yoon, Gi-Wan
    • 한국정보통신학회:학술대회논문집
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    • 한국해양정보통신학회 2005년도 춘계종합학술대회
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    • pp.117-121
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    • 2005
  • In this work, we first present our study on the decoding schemes for space-time block code as well as our comments on their complexity. Then, we propose a new modified complex sphere decoding scheme, which has lower computational load than that of conventional complex sphere decoders. In the proposed scheme, the boundary for searching is defined by the intersection of an approximate polygon of searching circle and disk of lattice constellation. Therefore, the proposed scheme can reduce the searching boundary and it can avoid missing searching points as well. The performance of the proposed scheme, which is verified by computer simulations, consolidates our scheme.

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Complexity Reduction for Space-Time Block Codes Decoder in MIMO OFDM Systems

  • Pham Van-Su;Le Minh-Tuan;Mai Linh;Yoon Giwan
    • Journal of information and communication convergence engineering
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    • 제3권2호
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    • pp.72-75
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    • 2005
  • In this work, we first present our study on the decoding schemes for space-time block code as well as our comments on their complexity. Then, we propose a new modified complex sphere decoding scheme, which has lower computational load than that of conventional complex sphere decoders. In the proposed scheme, the boundary for searching is aided with the intersection of approximate polygon of searching circle and disk of constellation. Therefore, the proposed scheme can reduce the searching boundary while can avoid missing searching points. The performance of the proposed scheme is verified by computer simulation that consolidates our scheme.

Theoretical Optical Waveguide Investigation of Self-Organized Polymer Thin Film Nanostructures with Nanoparticle Incorporation

  • Lau, King Hang Aaron;Knoll, Wolfgang;Kim, Dong-Ha
    • Macromolecular Research
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    • 제15권3호
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    • pp.211-215
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    • 2007
  • Hybrid thin film nanostructures composed of metal nanoparticles (NPs) and self-assembled polymer films with different spatial distributions of NPs were analyzed by optical waveguide spectroscopy (OWS). Specifically, the dielectric constants were calculated using effective medium theory for the incorporation of 1 vol% Au NP into the block copolymer (BCP) films having a cylindrical nanodomain morphology. Three cases were considered: uniform distribution of NPs in the film; selective distribution of NPs only in the cylindrical domains; and segregation of NPs to the center of the cylindrical domains. The optical waveguide spectra derived from the calculated dielectric constants demonstrate the feasibility of experimentally distinguishing the composite nanostructures with different inner morphologies in the hybrid metal NP-BCP nanostructures, by the measurement of the dielectric constants using OWS.

Design of initial support required for excavation of underground cavern and shaft from numerical analysis

  • Oh, Joung;Moon, Taehyun;Canbulat, Ismet;Moon, Joon-Shik
    • Geomechanics and Engineering
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    • 제17권6호
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    • pp.573-581
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    • 2019
  • Excavation of underground cavern and shaft was proposed for the construction of a ventilation facility in an urban area. A shaft connects the street-level air plenum to an underground cavern, which extends down approximately 46 m below the street surface. At the project site, the rock mass was relatively strong and well-defined joint sets were present. A kinematic block stability analysis was first performed to estimate the required reinforcement system. Then a 3-D discontinuum numerical analysis was conducted to evaluate the capacity of the initial support and the overall stability of the required excavation, followed by a 3-D continuum numerical analysis to complement the calculated result. This paper illustrates the application of detailed numerical analyses to the design of the required initial support system for the stability of underground hard rock mining at a relatively shallow depth.

Blockchain and Cryptocurrency Distributed Testing Methods

  • Lee, Taegyu
    • International Journal of Internet, Broadcasting and Communication
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    • 제14권1호
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    • pp.1-9
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    • 2022
  • Recently, a large number of cryptocurrencies and block chains have been continuously released. However, these cryptocurrencies and block chains are open to users without authorized verification and testing procedures, causing various reliability problems. Existing cryptocurrencies and blockchain test methods build a blockchain Testnet for a certain period of time by the developer without external verification by a third party, and after repeatedly self-testing and self-operating processes, commercialization is in progress by switching to the Mainnet. This self-verification method does not guarantee objectivity and publicness, and high reliability of customers cannot be realized. This study proposes a cryptocurrency and blockchain test interface and test control system as a third-party open test method.

딥러닝을 이용한 돼지 얼굴 인식 (Pig Face Recognition Using Deep Learning)

  • 마리한;김상철
    • 한국정보처리학회:학술대회논문집
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    • 한국정보처리학회 2022년도 추계학술발표대회
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    • pp.493-494
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    • 2022
  • The development of livestock faces intensive farming results in a rising need for recognition of individual animals such as cows and pigs is related to high traceability. In this paper, we present a non-invasive biometrics systematic approach based on the deep-learning classification model to pig face identification. Firstly, in our systematic method, we build a ROS data collection system block to collect 10 pig face data images. Secondly, we proposed a preprocessing block in that we utilize the SSIM method to filter some images of collected images that have high similarity. Thirdly, we employ the improved image classification model of CNN (ViT), which uses the finetuning and pretraining technique to recognize the individual pig face. Finally, our proposed method achieves the accuracy about 98.66%.

Effect of Vermicompost in Combination with Bacterial and Mineral Fertilizers on the Yield of Vegetable Soybean

  • Bajracharya, S.K.;Shercahn, D.P.;Bhattarai, S.
    • 한국작물학회지
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    • 제52권1호
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    • pp.100-103
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    • 2007
  • A field experiment was conducted in Agronomy farm at an altitude of 1350 m. above sea level in a randomized complete block design with three replications and eight treatments on vegetable type soybean in 2005. The objective was to see the effect of vermicompost alone and in combination with Rhizobium inoculum and mineral fertilizers on the yield of vegetable soybean. The result showed higher number of nodules from the non inoculated plot, however, the nodules weight was highest from the inoculated plots. No significant difference was notice statistically on roots and shoots dry weight. Soybean grain was obtained highest (32.3%) over the non inoculated plot followed by vermicompost plus inoculated, however, there was non significant difference. There was a slight increment on grain and straw yield from the inoculated plots over the non inoculated.