• 제목/요약/키워드: efficient computation

검색결과 1,281건 처리시간 0.023초

On Minimalist Requirements in Syntax

  • Lee, Hong-Bae
    • 한국영어학회지:영어학
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    • 제3권2호
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    • pp.255-280
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    • 2003
  • The present paper will argue what can be considered to be principled elements of the initial state S/sub 0/ of the Faculty of Language, which are called the Interface Condition (IC), and how far we can take the strongest minimalist thesis (SMT), which aims to offer principled explanation of language in terms of IC and the principle of efficient computation, to linguistic analysis. We will discuss implications of label-free phrase structures, required by the strong version of the Inclusiveness Condition, and possibilities of crash-free syntax, required by the condition of efficient computation. I will point out problems of Chomsky's assumption that an externally Merged expletive there is a head, which, as a probe, undergoes agreement with the goal T. I will present several advantages we obtain if we maintain A and A' distinction, and assume that wh-movement to the outer [SPEC, υ] is an A'-movement like wh-movement to [SPEC, C].

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하이브리드기법을 이용한 저마하수 난류소음의 효율적 전산해석 (Efficient Computation of Turbulent Flow Noise at Low Mach Numbers Via Hybrid Method)

  • 서정희;문영준
    • 대한기계학회논문집B
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    • 제31권9호
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    • pp.814-821
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    • 2007
  • A hybrid method is presented for efficient computation of turbulent flow noise at low Mach numbers. In this method, the turbulent flow field is computed by incompressible large eddy simulation (LES), while the acoustic field is computed with the linearized perturbed compressible equations (LPCE) derived in this study. Since LPCE is computed on the rather coarse acoustic grid with the flow variables and source term obtained by the incompressible LES, the computational efficiency of calculation is greatly enhanced. Furthermore, LPCE suppress the instability of perturbed vortical mode and therefore secure consistent and stable acoustic solutions. The proposed LES/LPCE hybrid method is applied to three low Mach number turbulent flow noise problems: i) circular cylinder, ii) isolated flat plate, and iii) interaction between cylinder wake and airfoil. The computed results are closely compared with the experimental measurements.

여유 자유도를 갖는 미니퓰레이터의 기구학적 제어를 위한 효율적 계산 방법 (An Efficient Computation Method for Kinematic Control of Redundant Manipulators)

  • 이경수;서일홍;임준홍
    • 대한전자공학회논문지
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    • 제25권4호
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    • pp.379-385
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    • 1988
  • A kinematic control for redundant manipulators is consisdered. An efficient computation method is proposed to determine the joint variable solutions for a given Cartesian path of the end effector. In the proposed method, the Jacobian matrix and its pseudoinverse matrix are calculated intermittently only when the errors exceed the prescribed tolerance. Thereby, the computational burdens are greatly reduced, and at the same time, the errors are maintained within a tolerable range. To show the effectiveness of the mehtod, the result of the simulation is provided in which the redundancy of the manipulator is resolved to avoid the singularity.

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셀 분할을 이용한 거리장의 효율적 계산 (Efficient Calculation of Distance Fields Using Cell Subdivision)

  • 유동진
    • 한국정밀공학회지
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    • 제25권3호
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    • pp.147-156
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    • 2008
  • A new approach based on cone prism intersection method combined with sorting algorithm is proposed for the fast and robust signed distance field computation. In the method, the space bounding the geometric model composed of triangular net is divided into multiple smaller cells. For the efficient calculation of distance fields, valid points among the triangular net which will generate minimum distances with current cell are selected by checking the intersection between current cell and cone prism generated at each point. The method is simple to implement and able to achieve an order of magnitude improvement in the computation time as compared to earlier approaches. Further the method is robust in handling the traditional sign problems. The validity of the suggested method was demonstrated by providing numerous examples including Boolean operation, shape deformation and morphing of complex geometric models.

다양한 해석조건을 갖는 항공기에 대한 효율적인 플러터 해석 (Efficient Flutter Analysis for Aircraft with Various Analysis Conditions)

  • 이상욱;김태욱;황인희;백승길
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2005년도 추계 학술대회논문집(수송기계편)
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    • pp.49-52
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    • 2005
  • Flutter analysis procedure can be divided into two steps such as the computation of generalized mass, stiffness, and unsteady aerodynamic matrices and the calculation of major vibration modes frequency and damping values at each flight speed by solving the complex eigenvalue problem. In aircraft flutter analyses, most of the time is spent in the process of computing the unsteady aerodynamic matrices at each Mach-reduced frequency pairs defined. In this study, the method has been presented for computation and extraction of unsteady aerodynamic matrix portions dependent only on aerodynamic model using DMAP ALTER in MSC/NASTRAN SOL 145. In addition, efficient flutter analysis method has been suggested by computing and utilizing the unsteady generalized aerodynamic matrices for each analysis condition using the unsteady aerodynamic matrix portions extracted above.

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A MODIFIED EXTENDED KALMAN FILTER METHOD FOR MULTI-LAYERED NEURAL NETWORK TRAINING

  • KIM, KYUNGSUP;WON, YOOJAE
    • Journal of the Korean Society for Industrial and Applied Mathematics
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    • 제22권2호
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    • pp.115-123
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    • 2018
  • This paper discusses extended Kalman filter method for solving learning problems of multilayered neural networks. A lot of learning algorithms for deep layered network are sincerely suffered from complex computation and slow convergence because of a very large number of free parameters. We consider an efficient learning algorithm for deep neural network. Extended Kalman filter method is applied to parameter estimation of neural network to improve convergence and computation complexity. We discuss how an efficient algorithm should be developed for neural network learning by using Extended Kalman filter.

Robust and Efficient 3D Model of an Electromagnetic Induction (EMI) Sensor

  • Antoun, Chafic Abu;Perriard, Yves
    • Journal of international Conference on Electrical Machines and Systems
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    • 제3권3호
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    • pp.325-330
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    • 2014
  • Eddy current induction is used in a wide range of electronic devices, for example in detection sensors. Due to the advances in computer hardware and software, the need for 3D computation and system comprehension is a requirement to develop and optimize such devices nowadays. Pure theoretical models are mostly limited to special cases. On the other hand, the classical use of commercial Finite Element (FE) electromagnetic 3D models is not computationally efficient and lacks modeling flexibility or robustness. The proposed approach focuses on: (1) implementing theoretical formulations in 3D (FE) model of a detection device as well as (2) an automatic Volumetric Estimation Method (VEM) developed to selectively model the target finite elements. Due to these two approaches, this model is suitable for parametric studies and optimization of the number, location, shape, and size of PCB receivers in order to get the desired target discrimination information preserving high accuracy with tenfold reduction in computation time compared to commercial FE software.

EETCA: Energy Efficient Trustworthy Clustering Algorithm for WSN

  • Senthil, T.;Kannapiran, Dr.B.
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제10권11호
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    • pp.5437-5454
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    • 2016
  • A Wireless Sensor Network (WSN) is composed of several sensor nodes which are severely restricted to energy and memory. Energy is the lifeblood of sensors and thus energy conservation is a critical necessity of WSN. This paper proposes a clustering algorithm namely Energy Efficient Trustworthy Clustering algorithm (EETCA), which focuses on three phases such as chief node election, chief node recycling process and bi-level trust computation. The chief node election is achieved by Dempster-Shafer theory based on trust. In the second phase, the selected chief node is recycled with respect to the current available energy. The final phase is concerned with the computation of bi-level trust, which is triggered for every time interval. This is to check the trustworthiness of the participating nodes. The nodes below the fixed trust threshold are blocked, so as to ensure trustworthiness. The system consumes lesser energy, as all the nodes behave normally and unwanted energy consumption is completely weeded out. The experimental results of EETCA are satisfactory in terms of reduced energy consumption and prolonged lifetime of the network.

Efficient methods for integrating weight function: a comparative analysis

  • Dubey, Gaurav;Kumar, Shailendra
    • Structural Engineering and Mechanics
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    • 제55권4호
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    • pp.885-900
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    • 2015
  • This paper introduces Romberg-Richardson's method as one of the numerical integration tools for computation of stress intensity factor in a pre-cracked specimen subjected to a complex stress field across the crack faces. Also, the computation of stress intensity factor for various stress fields using existing three methods: average stress over interval method, piecewise linear stress method, piecewise quadratic method are modified by using Richardson extrapolation method. The direct integration method is used as reference for constant and linear stress distribution across the crack faces while Gauss-Chebyshev method is used as reference for nonlinear distribution of stress across the crack faces in order to obtain the stress intensity factor. It is found that modified methods (average stress over intervals-Richardson method, piecewise linear stress-Richardson method, piecewise quadratic-Richardson method) yield more accurate results after a few numbers of iterations than those obtained using these methods in their original form. Romberg-Richardson's method is proven to be more efficient and accurate than Gauss-Chebyshev method for complex stress field.

연산공유 승산 알고리즘을 이용한 내적의 최적화 및 이를 이용한 1차원 DCT 프로세서 설계 (Optimization Design Method for Inner Product Using CSHM Algorithm and its Application to 1-D DCT Processor)

  • 이태욱;조상복
    • 대한전기학회논문지:시스템및제어부문D
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    • 제53권2호
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    • pp.86-93
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    • 2004
  • The DCT algorithm needs an efficient hardware architecture to compute inner product. The conventional design method, like ROM-based DA(Distributed Arithmetic), has large hardware complexity. Because of this reason, a CSHM(Computation Sharing Multiplication) was proposed for implementing inner product by Park. However, the Park's CSHM has inefficient hardware architecture in the precomputer and select units. Therefore it degrades the performance of the multiplier. In this paper, we presents the optimization design method for inner product using CSHM algorithm and applied it to implementation of 1-D DCT processor. The experimental results show that the proposed multiplier is more efficient than Park's when hardware architectures and logic synthesis results were compared. The designed 1-D DCT processor by using proposed design method is more high performance than typical methods.