• Title/Summary/Keyword: scheme

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A Flexible Redundancy Scheme for Wide Data-width DRAM (Wide Data-width DRAM을 위한 Flexible Redundancy Scheme)

  • 전용원;이정환김석기전영현
    • Proceedings of the IEEK Conference
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    • 1998.10a
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    • pp.711-714
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    • 1998
  • 본 논문에서는 wide data-width DRAM을 위한 flexible column redundancy scheme을 제안하였다. 구현된 redundancy scheme은 DB line shift method를 사용하여 wide data-width를 갖는 고집적 DRAM에 적용할 때 기존 redundancy scheme보다 더 작은 redundancy cell 면적과 fuse개수를 가지면서 더 큰 flexibility를 가지게 되었다.

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MIMO-FTN Transceiver Structure Using W-ZF Method (W-ZF 기법을 이용한 MIMO-FTN 송수신 구조 연구)

  • Seo, Jung-hyun;Jung, Ji-won
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.21 no.7
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    • pp.1291-1298
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    • 2017
  • In this paper, we propose a decoding method that improves the transmission rate and reliability by integrating MIMO(Multiple Input Multiple Output) communication scheme using turbo code and FTN(Faster Than Nyquist) scheme among high rate and high reliability wireless communication schemes in wireless communication. The existing MIMO-FTN(Multiple Input Multiple Output-Faster Than Nyquist) scheme based on hierarchical space-time coded method induced data rate loss due to the application of the space-time trellis coding scheme to remove adjacent symbol interference due to FTN scheme. To solve these problems, this paper proposes a method using W-ZF(Weighted-Zero Forcing) which overcomes the disadvantages of ZF(Zero Forcing) scheme in MIMO-FTN scheme using ZF scheme. In this paper, we compared the performance and the transmission rate of the MIMO-FTN scheme based on the hierarchical space-time coding, the MIMO-FTN scheme using W-ZF and the SISO-FTN scheme. As a result, the MIMO-FTN scheme using the W-ZF scheme is two times better than the other two schemes.

Randomized Scheme for Cognizing Tags in RFID Networks and Its Optimization

  • Choi, Cheon Won
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.12 no.4
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    • pp.1674-1692
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    • 2018
  • An RFID network is a network in which a reader inquire about the identities of tags and tags respond with their identities to a reader. The diversity of RFID networks has brought about many applications including an inexpensive system where a single reader supports a small number of tags. Such a system needs a tag cognizance scheme that is able to arbitrate among contending tags as well as is simple enough. In this paper, confining our attention to a clan of simple schemes, we propose a randomized scheme with aiming at enhancing the tag cognizance rate than a conventional scheme. Then, we derive an exact expression for the cognizance rate attained by the randomized scheme. Unfortunately, the exact expression is not so tractable as to optimize the randomized scheme. As an alternative way, we develop an upper bound on the tag cognizance rate. In a closed form, we then obtain a nearly optimal value for a key design parameter, which maximizes the upper bound. Numerical examples confirm that the randomized scheme is able to dominate the conventional scheme in cognizance rate by employing a nearly optimal value. Furthermore, they reveal that the randomized scheme is robust to the fallacy that the reader believes or guesses a wrong number of neighboring tags.

Comparison of Breeding System Between Single Population and Two Sub-population Scheme by Computer Simulation I. Equal genetic level for Sub-populations

  • Oikawa, T.;Matsura, Y.;Sato, K.
    • Asian-Australasian Journal of Animal Sciences
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    • v.10 no.4
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    • pp.422-427
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    • 1997
  • Breeding efficiency was investigated to reveal crucial factors for constructing effective breeding system with subdivided populations under equal genetic level. Simulation study of selection experiment was performed for 20 generations with 20 replications each, comparing average breeding values and inbreeding coefficients between the two breeding systems; single population scheme and two population scheme, each of which had the same genetic parameters. Genetic correlations (-0.5 to 0.5) were assumed to be caused only by pleiotropic effect of a gene. Phenotypes of the two traits generated by polygenic effect with additive 36 loci and residuals distributed normally were selected by two traits selection index procedure. Comparing between the single population scheme and the two population scheme, the single population scheme showed higher genetic gain with lower inbreeding coefficient. This result was confirmed particularly for the situation of high selection intensity, high heritability and high degree of unevenness for economic weight. Genetic correlations in the single population scheme were significantly lower than the two population scheme when initial genetic correlation was negative. When terminal crossbreeding for the two population scheme is taken into account, superiority of the two population scheme was suggested. The terminal crossbreeding was effective under the situation of long term selection, existence of moderate inbreeding depression and use of less extreme economic weight.

CONSTRUCTION OF A SYMMETRIC SUBDIVISION SCHEME REPRODUCING POLYNOMIALS

  • Ko, Kwan Pyo
    • Communications of the Korean Mathematical Society
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    • v.31 no.2
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    • pp.395-414
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    • 2016
  • In this work, we study on subdivision schemes reproducing polynomials and build a symmetric subdivision scheme reproducing polynomials of a certain predetermined degree, which is a slight variant of the family of Deslauries-Dubic interpolatory ones. Related to polynomial reproduction, a necessary and sufficient condition for a subdivision scheme to reproduce polynomials of degree L was recently established under the assumption of non-singularity of subdivision schemes. In case of stepwise polynomial reproduction, we give a characterization for a subdivision scheme to reproduce stepwise all polynomials of degree ${\leq}L$ without the assumption of non-singularity. This characterization shows that we can investigate the polynomial reproduction property only by checking the odd and even masks of the subdivision scheme. The minimal-support condition being relaxed, we present explicitly a general formula for the mask of (2n + 4)-point symmetric subdivision scheme with two parameters that reproduces all polynomials of degree ${\leq}2n+1$. The uniqueness of such a symmetric subdivision scheme is proved, provided the two parameters are given arbitrarily. By varying the values of the parameters, this scheme is shown to become various other well known subdivision schemes, ranging from interpolatory to approximating.

HYBRID Scheme vs. QUICKER Scheme : Comparison Based on Lid-driven Cavity flow Computations (HYBRID기법과 QUICKER기법 : 공동 유동의 계산 특성 비교)

  • 조성호;강인준;박승오
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.17 no.6
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    • pp.1640-1647
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    • 1993
  • The numerical diffusion arising from streamline-to-grid skewness produces a deteriorating effect on the numerical accuracy. The QUICKER scheme to reduce the numerical diffusion requires more computational effort than the HYBRID scheme. This paper deals with the relative computational efficiencies of adopting QUICKER scheme with a coarser grid system and of adopting HYBRID scheme with a denser grid system. Laminar driven cavity flow with Re=400, 1000 is used as a test problem. It is found that QUICKER scheme with a coarser grid system is more efficient than the HYBRID scheme with a denser grid system.

Fully Collusion-Resistant Trace-and-Revoke Scheme in Prime-Order Groups

  • Park, Jong-Hwan;Rhee, Hyun-Sook;Lee, Dong-Hoon
    • Journal of Communications and Networks
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    • v.13 no.5
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    • pp.428-441
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    • 2011
  • A trace-and-revoke scheme is a type of broadcast encryption scheme for content protection on various platforms such as pay-per-view TV and DVD players. In 2006, Boneh and Waters (BW) presented a fully collusion-resistant trace-and-revoke scheme. However, a decisive drawback of their scheme is to require composite-order groups. In this paper, we present a new trace-and-revoke scheme that works in prime-order groups. Our scheme is fully collusion-resistant and achieves ciphertexts and private keys of size O($\sqrt{N}$) for N users. For the same level of security, our scheme is better than the BW scheme in all aspects of efficiency. Some superior features include 8.5 times faster encryption, 12 times faster decryption, and 3.4 times shorter ciphertexts. To achieve our goal, we introduce a novel technique where, by using asymmetric bilinear maps in prime-order groups, the cancellation effect same as in composite-order groups can be obtained.

Sequential Least Square Channel Estimation in OFDM Systems (OFDM 시스템에서의 Sequential Least Squares 채널 추정 방식)

  • 고은석;박병준;천현수;강창언;홍대식
    • Proceedings of the IEEK Conference
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    • 2000.06a
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    • pp.45-48
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    • 2000
  • The use of multi-level modulation scheme in the wireless LAN(Local Area Networks) system requires an accurate channel estimation. In this paper, we present sequential least squares(LS) channel estimation scheme based on decision-directed channel tracking scheme. The proposed scheme improves the performance of the conventional LS estimator for wireless LAN. In addition, its structure is suitable for the high-rate wireless LAN. Simulation results show that the proposed scheme achieves about IdB Packet Error Rate(PER) gain compared to the LS scheme in a frequency selective channel.

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Vibration suppression of flexible structures using optimal model following control scheme (최적 모델추종 제어기법을 이용한 유연 구조물 진동 억제에 관한 연구)

  • 양철호;김유단
    • 제어로봇시스템학회:학술대회논문집
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    • 1993.10a
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    • pp.931-936
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    • 1993
  • Optimal model following control scheme is to design the controller which makes the response of real system follow that of desirable model. This kind of design scheme is developed for first order system. We extends the scheme for second order system regarding the characteristics of mechanical second order system for vibration suppression of flexible structures. The model of mechanical second order system is obtained using suitable damping ratios and natural frequencies. Using this scheme, we can design the good controller which uses the characteristic of second order system. Numerical examples are presented which were used optimal model following control scheme.

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An EIGamal Signature Scheme using Cellular Automata (CA를 이용한 EIGamal 서명기법)

  • 이준석;장화식;이경현
    • Convergence Security Journal
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    • v.2 no.2
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    • pp.143-153
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    • 2002
  • In this paper, we propose a multiplication scheme based on cellular automata and propose high speed multiplication scheme and exponentiation scheme using a optimal normal basis. And then EIGamal signature scheme is implemented by proposed schemes. A proposed multiplication and exponentiation scheme based on cellular automata can be used in restricted computing environments such that basis is frequently changed and cryptosystem and multimedia applications that are required high speed operations.

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