• Title/Summary/Keyword: Series Expansion

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IEEE-754 Floating-Point Divider for Embedded Processors (내장형 프로세서를 위한 IEEE-754 고성능 부동소수점 나눗셈기의 설계)

  • Jeong, Jae-Won;Hong, In-Pyo;Jeong, Woo-Kyong;Lee, Yong-Surk
    • Journal of the Institute of Electronics Engineers of Korea SD
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    • v.39 no.7
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    • pp.66-73
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    • 2002
  • As floating-point operations become widely used in various applications such as computer graphics and high-definition DSP, the needs for fast division become increased. However, conventional floating-point dividers occupy a large hardware area, and bring bottle-becks to the entire floating-point operations. In this paper, a high-performance and small-area floating-point divider, which is suitable for embedded processors, is designed using he series expansion algorithm. The algorithm is selected to utilize two MAC(Multiply-ACcumulate) units for quadratic convergence to the correct quotient. The two MAC units for SIMD-DSP features are shared and the additional area for the division only is very small. The proposed divider supports all rounding modes defined by IEEE 754 standard, and error estimations are performed for appropriate precision.

Next-generation gene targeting in the mouse for functional genomics

  • Gondo, Yoichi;Fukumura, Ryutaro;Murata, Takuya;Makino, Shigeru
    • BMB Reports
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    • v.42 no.6
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    • pp.315-323
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    • 2009
  • In order to elucidate ultimate biological function of the genome, the model animal system carrying mutations is indispensable. Recently, large-scale mutagenesis projects have been launched in various species. Especially, the mouse is considered to be an ideal model to human because it is a mammalian species accompanied with well-established genetic as well as embryonic technologies. In 1990', large-scale mouse mutagenesis projects firstly initiated with a potent chemical mutagen, N-ethyl-N-nitrosourea (ENU) by the phenotype-driven approach or forward genetics. The knockout mouse mutagenesis projects with trapping/conditional mutagenesis have then followed as Phase II since 2006 by the gene-driven approach or reverse genetics. Recently, the next-generation gene targeting system has also become available to the research community, which allows us to establish and analyze mutant mice carrying an allelic series of base substitutions in target genes as another reverse genetics. Overall trends in the large-scale mouse mutagenesis will be reviewed in this article particularly focusing on the new advancement of the next-generation gene targeting system. The drastic expansion of the mutant mouse resources altogether will enhance the systematic understanding of the life. The construction of the mutant mouse resources developed by the forward and reverse genetic mutagenesis is just the beginning of the annotation of mammalian genome. They provide basic infrastructure to understand the molecular mechanism of the gene and genome and will contribute to not only basic researches but also applied sciences such as human disease modelling, genomic medicine and personalized medicine.

Free Vibrations of Linearly Tapered I-Beams (선형(線形) 변단면(變斷面) I-형(型) 부재(部材)의 자유진동(自由振動))

  • Lee, Yong Woo;Min, Kyung Ju
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.14 no.5
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    • pp.1023-1031
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    • 1994
  • The closed forms of consistent mass matrix with rotational inertia matrix are developed for free vibration analysis in space sutructures containing linearly tapered members with cross section of thin-walled I-sections. The exact displacement functions are used for formulating mass matrices. The very small slopes of the tapered member are used in usual practice, such that the series expansion forms of these are also developed to avoid numerical failure in vibration analysis. Significant improvements of accuracy and efficiency of free vibation analysis are achieved by using the mass matrices developed in this study. Frequencies of free vibation of tapered members are compared with solutions based upon stepped representation of beam element in the ANSYS. The mass matrices presented in this study can be used for the free vibration analysis of tapered and prismatic members.

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Design of Square Root and Inverse Square Root Arithmetic Units for Mobile 3D Graphic Processing (모바일 3차원 그래픽 연산을 위한 제곱근 및 역제곱근 연산기 구조 및 설계)

  • Lee, Chan-Ho
    • Journal of the Institute of Electronics Engineers of Korea SD
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    • v.46 no.3
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    • pp.20-25
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    • 2009
  • We propose hardware architecture of floating-point square root and inverse square root arithmetic units using lookup tables. They are used for lighting engines and shader processor for 3D graphic processing. The architecture is based on Taylor series expansion and consists of lookup tables and correction units so that the size of look-up tables are reduced. It can be applied to 32 bit floating point formats of IEEE-754 and reduced 24 bit floating point formats. The square root and inverse square root arithmetic units for 32 bit and 24 bit floating format number are designed as the proposed architecture. They can operation in a single cycle, and satisfy the precision of $10^{-5}$ required by OpenGL 1.x ES. They are designed using Verilog-HDL and the RTL codes are verified using an FPGA.

Characteristics of Soil Parameter for Lade's Single Work-Hardening Constitutive Model with Dry Density of Pocheon Granite Soil (포천 화강토의 건조단위중량에 따른 Lade의 단일항복면 구성모델의 토질매개변수 특성)

  • Cho, Won-Beom;Kim, Chan-Kee
    • Journal of the Korean Geosynthetics Society
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    • v.10 no.4
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    • pp.29-36
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    • 2011
  • In this study, a series of the isotropic compression-expansion tests and the drained triaxial tests were performed on Pocheon granite soil with various the dry densities of $16.67kN/m^3$, $17.26kN/m^3$ and $17.65kN/m^3$. Using the tests results the characteristic of the parameters of Lade's single hardening constitutive model were investigated. The soil parameters such as kur and n related to elastic behavior, m and ${\eta}_1$ related to failure criterion, c and p related to hardening function and ${\psi}_2$ and ${\mu}$ related to plastic potential show in a positive linear relationship with the dry density. Since the soil parameters h and representing yield function do not change much to relative density and also are closely related to failure criterion, they can be replaced by failure criterion. We also observed that predicted values from the Lade's single hardening constitutive model were well consistent with the observed data.

Development of a Cycle Simulation Program for Multi-Airconditioning Systems using R410A (R410A를 사용하는 멀티에어컨 시스템을 위한 사이클 시뮬레이션 프로그램 개발)

  • Kim, Young-Jae;Park, In-Sub;Kim, Hak-Hee;Yoon, Baek;Gil, Sung-Ho
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.3 no.3
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    • pp.210-215
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    • 2002
  • In this study, the computer program called Multi_Cycle, which simulates the steady-state performance (coefficient of performance, capacity, power consumption and etc.) of multi- airconditioning systems using R410A, was developed. In order to validate the simulation program, a series of case studies were carried out. The Multi_Cycle consists of several subroutines for simulating indoor units. outdoor unit, compressor, and expansion devices. and for estimating the thermodynamic and transport properties of the refrigerants and moist air. It would appear to be advantageous to use the Multi_Cycle for a performance analysis when considering various kinds of refrigerants and the complex operating conditions of each unit making up the multi-airconditioner cycle. Moreover, the Multi_Cycle would seem to be useful tool in optimizing a multi-airconditioning system and establishing economical and efficient operating conditions in the multi-airconditioner cycle. In the present study, the Multi_Cycle was programmed with Digital Visual Fortran for the main simulation code and Visual Basic for- the graphic user interface.

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Cycle Property in the (n,k)-star Graph ((n,k)-스타 그래프의 사이클 특성)

  • Chang, Jung-Hwan
    • The Transactions of the Korea Information Processing Society
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    • v.7 no.5
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    • pp.1464-1473
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    • 2000
  • In this paper, we analyze the cycle property of the (n,k)-star graph that has an attention as an alternative interconnection network topology in recent years. Based on the graph-theoretic properties in (n,k)-star graphs, we show the pancyclic property of the graph and also present the corresponding algorithm. Based on the recursive structure of the graph, we present such top-down approach that the resulting cycle can be constructed by applying series of "dimension expansion" operations to a kind of cycles consisting of sub-graphs. This processing naturally leads to such property that the resulting cycles tend to be integrated compactly within some minimal subset of sub-graphs, and also means its applicability of another classes of the disjoint-style cycle problems. This result means not only the graph-theoretic contribution of analyzing the pancyclic property in the underlying graph model but also the parallel processing applications such a as message routing or resource allocation and scheduling in the multi-computer system with the corresponding interconnection network.

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A Study on Query Refinement by Online Relevance Feedback in an Information Filtering System (온라인 이용자 피드백을 사용한 정보필터링 시스템의 수정질의 최적화에 관한 연구)

  • Choi, Kwang;Chung, Young-Mee
    • Journal of the Korean Society for information Management
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    • v.20 no.4 s.50
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    • pp.23-48
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    • 2003
  • In this study an information filtering system was implemented and a series of relevance feedback experiments were conducted using the system. For the relevance feedback, the original queries were searched against the database and the results were reviewed by the researchers. Based on users' online relevance judgements a pair of 17 refined queries were generated using two methods called 'co-occurrence exclusion method' and 'lower frequencies exclusion method,' In order to generate them, the original queries, the descriptors and category codes appeared in either relevant or irrelevant document sets were applied as elements. Users' relevance judgments on the search results of the refined queries were compared and analyzed against those of the original queries.

Speech Quality Measure for VoIP Using Wavelet Based Bark Coherence Function (웨이블렛 기반 바크 코히어런스 함수를 이용한 VoIP 음질평가)

  • 박상욱;박영철;윤대희
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.27 no.4A
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    • pp.310-315
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    • 2002
  • The Bark Coherence Function (BCF) defies a coherence function within perceptual domain as a new cognition module, robust to linear distortions due to the analog interface of digital mobile system. Our previous experiments have shown the superiority of BCF over current measures. In this paper, a new BCF suitable for VoIP is developed. The unproved BCF is based on the wavelet series expansion that provides good frequency resolution while keeping good time locality. The proposed Wavelet based Bark Coherence function (WBCF) is robust to variable delay often observed in packet-based telephony such as Voice over Internet Protocol (VoIP). We also show that the refinement of time synchronization after signal decomposition can improve the performance of the WBCF. The regression analysis was performed with VoIP speech data. The correlation coefficients and the standard error of estimates computed using the WBCF showed noticeable improvement over the Perceptual Speech Quality Measure (PSQM) that is recommended by ITU-T.

Modeling and State Observer Design for Roll Slip in Cold Cluster Mills (냉간압연 다단 압연기의 롤 슬립 모델링 및 상태 관측기 설계)

  • Kang, Hyun Seok;Hong, Wan Kee;Hwang, I Cheol
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.36 no.12
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    • pp.1543-1549
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    • 2012
  • This study focuses on the state space model and the design of a state observer for the slip dynamics between rolls in STS cold cluster mills. First, a mathematical model of the roll slip is given as a nonlinear differential equation. Then, by using a Taylor series expansion, it is linearized as a state space model. Next, by using Gopinath's algorithm, a minimal-order state observer based on the state space model is designed to estimate the angular speed of all idle rolls except for an actuated roll that is measureable. Finally, a computer simulation is used to validate that the proposed state space model very well describes slip dynamics between, and moreover, the state observer very well estimates the angular speed of the idle roll.