• Title/Summary/Keyword: Basis Set

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Analysis of Transient Electromagnetic Scattering from 3-Dimensional Dielectric Objects by using Time-Domain PMCHW Integral Equation (시간영역 PMCHW 적분식을 이용한 3차원 유전체의 전자파 과도 산란 해석)

  • 정백호;서정훈;한상호
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.14 no.10
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    • pp.1096-1103
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    • 2003
  • In this paper, we analyze the transient electromagnetic response from three-dimensional(3-D) dielectric bodies using a time-domain PMCHW(Poggio, Miller, Chang, Harrington, Wu) formulation. The solution method in this paper is based on the Galerkin's method that involves separate spatial and temporal testing procedures. Triangular patch basis functions are used for spatial expansion and testing functions for arbitrarily shaped 3-D dielectric structures. The time-domain unknown coefficients of the equivalent currents are approximated by a set of orthonormal basis functions that are derived from the Laguerre polynomials. These basis functions are also used as the temporal testing. Numerical results involving equivalent currents and far fields computed by the proposed method are presented.

Formation Of Digital Culture Of Scientific And Pedagogical Workers In The Conditions Of General Digitalization Of Education

  • Kononenko, Andrii;Smyrnova, Iryna;Rybalko, Petro;Obraz, Vasyl;Balakhovska, Yuliia;Prepotenska, Maryna
    • International Journal of Computer Science & Network Security
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    • v.21 no.12
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    • pp.189-192
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    • 2021
  • The article theoretically substantiated, developed and practically implemented a structural and functional model of the formation of ICT competence, taking into account interdisciplinary integration, defines the pedagogical conditions that contribute to the formation of ICT competence: interdisciplinary integration as a basis for building an interdisciplinary course, the content of which is aimed at the formation of ICT competence; the use of IEE, including information, didactic, technological components as a basis for the formation of ICT competence; integration of formal, non-formal and informal education for the implementation the integrity of the acquired knowledge, skills, experience as the basis for the formation of the ICT competence of teachers; creation and use of a set of tasks (educational (UZ), educational and methodological (UMP), educational and professional (UPZ)) as special tools for the formation of ICT competence.

Structures and Barrier Heights for the Internal Rotation of Ethyl Halides Caculated by ab initio Methods

  • Ryu, Ung-Sik;Lee, Yoon-Sup
    • Bulletin of the Korean Chemical Society
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    • v.15 no.3
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    • pp.221-227
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    • 1994
  • The barrier heights of the internal rotations for ethyl halides calculated by ab initio methods differ from those of experiments by more than 0.2 kcal/mol. The use of basis sets larger than the $6-31G^{\ast}$ set and the inclusion of correlation do not improve the agreement between the calculated and experimental values. The zero-point vibration corrections are substantial in the HF calculations with $6-31G^{\ast}$ basis sets, but become negligible in the MP2 calculations with $6-311G^{{\ast}{\ast}}$ basis sets for $C_2H_5F\;and\;C_2H_5Cl$. It is shown that the rigid rotor approximation and the assumed shape of the potential curve as a cos2${\theta}$ curve could also be the sources of discrepancies between calculated and experimental values. Higher order perturbation corrections narrow the gap between experimental and theoretical values, but there still remains about 10% overestimate of 0.3 kcal/mol. Optimized geometries from the HF and MP2 calculations are in good agreement with those from experiments. Dipole moments calculated from the MP2 densities show slightly better agreement with experiments than those from the HF densities.

Statistical Analysis of Projection-Based Face Recognition Algorithms (투사에 기초한 얼굴 인식 알고리즘들의 통계적 분석)

  • 문현준;백순화;전병민
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.25 no.5A
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    • pp.717-725
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    • 2000
  • Within the last several years, there has been a large number of algorithms developed for face recognition. The majority of these algorithms have been view- and projection-based algorithms. Our definition of projection is not restricted to projecting the image onto an orthogonal basis the definition is expansive and includes a general class of linear transformation of the image pixel values. The class includes correlation, principal component analysis, clustering, gray scale projection, and matching pursuit filters. In this paper, we perform a detailed analysis of this class of algorithms by evaluating them on the FERET database of facial images. In our experiments, a projection-based algorithms consists of three steps. The first step is done off-line and determines the new basis for the images. The bases is either set by the algorithm designer or is learned from a training set. The last two steps are on-line and perform the recognition. The second step projects an image onto the new basis and the third step recognizes a face in an with a nearest neighbor classifier. The classification is performed in the projection space. Most evaluation methods report algorithm performance on a single gallery. This does not fully capture algorithm performance. In our study, we construct set of independent galleries. This allows us to see how individual algorithm performance varies over different galleries. In addition, we report on the relative performance of the algorithms over the different galleries.

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Performance Improvement of Radial Basis Function Neural Networks Using Adaptive Feature Extraction (적응적 특징추출을 이용한 Radial Basis Function 신경망의 성능개선)

  • 조용현
    • Journal of Korea Multimedia Society
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    • v.3 no.3
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    • pp.253-262
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    • 2000
  • This paper proposes a new RBF neural network that determines the number and the center of hidden neurons based on the adaptive feature extraction for the input data. The principal component analysis is applied for extracting adaptively the features by reducing the dimension of the given input data. It can simultaneously achieve a superior property of both the principal component analysis by mapping input data into set of statistically independent features and the RBF neural networks. The proposed neural networks has been applied to classify the 200 breast cancer databases by 2-class. The simulation results shows that the proposed neural networks has better performances of the learning time and the classification for test data, in comparison with those using the k-means clustering algorithm. And it is affected less than the k-means clustering algorithm by the initial weight setting and the scope of the smoothing factor.

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New N-dimensional Basis Functions for Modeling Surface Reflectance (표면반사율 모델링을 위한 새로운 N차원 기저함수)

  • Kwon, Oh-Seol
    • Journal of Broadcast Engineering
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    • v.17 no.1
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    • pp.195-198
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    • 2012
  • The N basis functions are typically chosen so that Surface reflectance functions(SRFs) and spectral power distributions (SPDs) can be accurately reconstructed from their N-dimensional vector codes. Typical rendering applications assume that the resulting mapping is an isomorphism where vector operations of addition, scalar multiplication, component-wise multiplication on the N-vectors can be used to model physical operations such as superposition of lights, light-surface interactions and inter-reflection. The vector operations do not mirror the physical. However, if the choice of basis functions is restricted to characteristic functions then the resulting map between SPDs/SRFs and N-vectors is anisomorphism that preserves the physical operations needed in rendering. This paper will show how to select optimal characteristic function bases of any dimension N (number of basis functions) and also evaluate how accurately a large set of Munsell color chips can approximated as basis functions of dimension N.

On the Design of Orthogonal Pulse-Shape Modulation for UWB Systems Using Hermite Pulses

  • Giuseppe, Thadeu Freitas de Abreu;Mitchell, Craig-John;Kohno, Ryuji
    • Journal of Communications and Networks
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    • v.5 no.4
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    • pp.328-343
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    • 2003
  • Orthogonal pulse-shape modulation using Hermite pulses for ultra-wideband communications is reviewed. Closedform expressions of cross-correlations among Hermite pulses and their corresponding transmit and receive waveforms are provided. These show that the pulses lose orthogonality at the receiver in the presence of differentiating antennas. Using these expressions, an algebraic model is established based on the projections of distorted receive waveforms onto the orthonormal basis given by the set of normalized orthogonal Hermite pulses. Using this new matrix model, a number of pulse-shape modulation schemes are analyzed and a novel orthogonal design is proposed. In the proposed orthogonal design, transmit waveforms are constructed as combinations of elementary Hermites with weighting coefficients derived by employing the Gram-Schmidt (QR) factorization of the differentiating distortion model’s matrix. The design ensures orthogonality of the vectors at the output of the receiver bank of correlators, without requiring compensation for the distortion introduced by the antennas. In addition, a new set of elementary Hermite Pulses is proposed which further enhances the performance of the new design while enabling a simplified hardware implementation.

A Study on the Adaptive Refinement Method for the Stress Analysis of the Meshfree Method (적응적 세분화 방법을 이용한 무요소법의 응력 해석에 관한 연구)

  • Han, Sang-Eul;Kang, Noh-Won;Joo, Jung-Sik
    • Proceedings of the Computational Structural Engineering Institute Conference
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    • 2008.04a
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    • pp.8-13
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    • 2008
  • In this study, an adaptive node generation procedure in the radial point interpolation method is proposed. Since we set the initial configuration of nodes by subdivision of background cell, abrupt changes of inter-nodal distance between higher and lower error regions are unavoidable. This unpreferable nodal spacing induces additional errors. To obtain the smoothy nodal configuration, it's regenerated by local Delaunay triangulation algorithm This technique was originally developed to generate a set of well-shaped triangles and tetrahedra. To demonstrate the performance of proposed scheme, the results of making optimal nodal configuration with adaptive refinement method are investigated for stress concentration problems.

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A Study on the Improvement of set-up of Required Operational Capability set up and Test & Evaluation method of Weapon System (무기체계 작전운용성능 설정 및 시험평가방법 개선에 대한 연구)

  • Eom, Dong Hwan
    • Journal of the Korean Society of Systems Engineering
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    • v.15 no.2
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    • pp.9-16
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    • 2019
  • The most important task in acquiring the weapon system is to determine the required performance and to test & evaluate it. The importance of the weapon system by ROC (Required Operational Capability) is not considered, and system development and test evaluation are carried out. In addition, technical incidental performance is tested on the same basis as ROC in the test evaluation and determined according to the result. Development test and evaluation that evaluates technical ability is very important, but development agency is supervised and performed. In this paper, we propose a method to give weights considering the importance of ROC, a technical incidental performance determination and test procedure, and a improvement plan for the development and operational test & evaluation.

The Solution of Vehicle Scheduling Problems with Multiple Objectives in a Probabilistic Environment

  • Park, Yang-Byung
    • Journal of Korean Institute of Industrial Engineers
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    • v.14 no.1
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    • pp.119-131
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    • 1988
  • Vehicle Scheduling Problem (VSP) is a generic name given to a whole class of problems involving the visiting of "stations" by "vehicles," where a time is associated with each activity. The studies performed to date have the common feature of a single objective while satisfying a set of restrictions and known customer supplies or demands. However, VSPs may involve relevant multiple objectives and probabilistic supplies or demands at stations, creating multicriteria stochastic VSPs. This paper proposes a heuristic algorithm based on goal programming approach to schedule the most satisfactory vehicle routes of a bicriteria VSP with probabilistic supplies at stations. The two relevant objectives are the minimization of the expected travel distance of vehicles and the minimization of the due time violation for collection service at stations by vehicles. The algorithm developed consists of three major stages. In the first stage, an artificial capacity of vehicle is determined, on the basis of decision maker's subjective estimates. The second one clusters a set of stations into subsets by applying an efficient cluster method developed. In the third one, the stations in each subset are scheduled by applying an iterative goal programming heuristic procedure to each cluster.

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