• 제목/요약/키워드: basis

검색결과 31,608건 처리시간 0.052초

Construction of Orthogonal Basis Functions with Non-Divergent Barotropic Rossby-Haurwitz Waves

  • Cheong, Hyeong-Bin;Jeong, Hanbyeol;Kim, Wonho
    • 한국지구과학회지
    • /
    • 제35권5호
    • /
    • pp.333-341
    • /
    • 2014
  • A new set of basis functions was constructed using the Rossby-Haurwitz waves, which are the eigenfunctions of nondivergent barotropic vorticity equations on the sphere. The basis functions were designed to be non-separable, that is, not factored into functions of either the longitude or the latitude. Due to this property, the nodal lines of the functions are aligned neither along with the meridian nor the parallel. The basis functions can be categorized into groups of which members have the same degree or the total wavenumber-like index on the sphere. The orthonormality of the basis functions were found to be close to the machine roundoffs, giving the error of $O(10^{-15})$ or $O(10^{-16})$ for double-precision computation (64 bit arithmetic). It was demonstrated through time-stepping procedure that the basis functions were also the eigenfunctions of the non-divergent barotropic vorticity equations. The projection of the basis functions was carried out onto the low-resolution geopotential field of Gaussian bell, and compared with the theory. The same projections were performed for the observed atmospheric-geopotential height field of 500 hPa surface to demonstrate decomposition into the fields that contain disturbance of certain range of horizontal scales. The usefulness of the new basis functions was thus addressed for application to the eigenmode analysis of the atmospheric motions on the global domain.

변형된 다항식 기저를 이용한 유한체의 연산 (Arithmetic of finite fields with shifted polynomial basis)

  • 이성재
    • 정보보호학회논문지
    • /
    • 제9권4호
    • /
    • pp.3-10
    • /
    • 1999
  • 유한체(Galois fields)가 타원곡선 암호법 coding 이론 등에 응용되면서 유한체의 연 산은 더많은 관심의 대상이 되고 있다. 유한체의 연산은 표현방법에 많은 영향을 받는다. 즉 최적 정규기 저는 하드웨 어 구현에 용이하고 Trinomial을 이용한 다항식 기저는 소프트웨어 구현에 효과적이다. 이논문에서는 새로운 변형된 다항식 기저를 소개하고 AOP를 이용한 경우 하드웨어 구현에 효과적인 최 적 정규기저와 의 변환이 위치 변화로 이루어지고 또한 이것을 바탕으로 한 유한체의 연산이 소프트웨어적 으로 효율적 임을 보인다. More concerns are concentrated in finite fields arithmetic as finite fields being applied for Elliptic curve cryptosystem coding theory and etc. Finite fields arithmetic is affected in represen -tation of those. Optimal normal basis is effective in hardware implementation and polynomial field which is effective in the basis conversion with optimal normal basis and show that the arithmetic of finite field with the basis is effective in software implementation.

THE DECISION OF OPTIMUM BASIS FUNCTION IN IMAGE CLASSIFICATION BASED ON WAVELET TRANSFORM

  • Yoo, Hee-Young;Lee, Ki-Won;Jin, Hong-Sung;Kwon, Byung-Doo
    • 대한원격탐사학회:학술대회논문집
    • /
    • 대한원격탐사학회 2008년도 International Symposium on Remote Sensing
    • /
    • pp.169-172
    • /
    • 2008
  • Land-use or land-cover classification of satellite images is one of the important tasks in remote sensing application and many researchers have been tried to enhance classification accuracy. Previous studies show that the classification technique based on wavelet transform is more effective than that of traditional techniques based on original pixel values, especially in complicated imagery. Various wavelets can be used in wavelet transform. Wavelets are used as basis functions in representing other functions, like sinusoidal function in Fourier analysis. In these days, some basis functions such as Haar, Daubechies, Coiflets and Symlets are mainly used in 2D image processing. Selecting adequate wavelet is very important because different results could be obtained according to the type of basis function in classification. However, it is not easy to choose the basis function which is effective to improve classification accuracy. In this study, we computed the wavelet coefficients of satellite image using 10 different basis functions, and then classified test image. After evaluating classification results, we tried to ascertain which basis function is the most effective for image classification. We also tried to see if the optimum basis function is decided by energy parameter before classifying the image using all basis function. The energy parameter of signal is the sum of the squares of wavelet coefficients. The energy parameter is calculated by sub-bands after the wavelet decomposition and the energy parameter of each sub-band can be a favorable feature of texture. The decision of optimum basis function using energy parameter in the wavelet based image classification is expected to be helpful for saving time and improving classification accuracy effectively.

  • PDF

벼의 횡류 연속식 건조 모델 개발과 퍼지논리를 이용한 건조 속도 제어에 관한 연구(II) - 건조속도제어 - (Development of Continuous Cross-Flow Rice Drying Model and Drying Speed Control System Using Fuzzy Logic(II) - Drying Speed Control -)

  • 송대빈;고학균;조성인
    • Journal of Biosystems Engineering
    • /
    • 제23권5호
    • /
    • pp.457-464
    • /
    • 1998
  • A drying speed control system using fuzzy logic was developed in order to minimize the damage of rice quality for a large capacity continuous dryer. The performance of the system was tested at two object moisture content of 17% and 25% on a wet basis. For object moisture content of 17% on a wet basis, the final output moisture contents from 20.46%, 20.96%, 18.98% on a wet basis were 17.99%, 17.6% and 17.23% on a wet basis, respectively. For object moisture content of 25% on a wet basis, the final output moisture contents from 28.85%, 26.95%, 28.11%, 27.8% on a wet basis were 25.24%, 24.9%, 25.23% and 25.09% on a wet basis, respectively.

  • PDF

지역 평량이 지역 변형률에 미치는 영향 (The Effect of Local Basis Weight on Local Strain)

  • 남원석;백기현
    • 펄프종이기술
    • /
    • 제31권3호
    • /
    • pp.105-109
    • /
    • 1999
  • The purpose of this experiment was to see the effect of local basis weight on the local strain during changing moisture content in handsheets. The averaged strain value of the whole size of paper sheet did not give more valuable information to explain non uniform deformation in the paper sheet. The combination of intact strain measurement system KISA (Linear Image Strain Analysis) and local basis weight measurement method using a scanner made it possible to compare local basis weight with local strain to explain moisture induced paper deformation . Usually higher basis weight local area showed higher moisture induced local strain. However, the hygro-induced strain values were highly affected by the behavior of neighbor local areas. Well distributed local basis weight paper would give more uniform local strains than those of non-uniformed local basis weight paper.

  • PDF

Comparison Chosen DFT Methods with Six Basis Sets on Harmine Molecule

  • Malekzadeh, Maryam;Heshmati, Emran
    • 대한화학회지
    • /
    • 제57권1호
    • /
    • pp.20-24
    • /
    • 2013
  • The effect of the DFT methods and basis sets on harmine molecule has been investigated. 26 DFT methods with 6 basis sets were used. Two main comparison chosen DFT methods in this work has been investigated. It is concluded that this contribution is very important and cannot be neglected. In the following analysis, changes in energy levels were investigated by two different methods. Considering a specific basis set, changes in energy levels were obtained using different DFT methods. A specific DFT method is chosen and changes in energy levels have been investigated by means of various basis sets. Effect of the choice of basis sets on geometrical parameters on harmine molecule has also been investigated.

AFFINE TRANSFORMATION OF A NORMAL ELEMENT AND ITS APPLICATION

  • Kim, Kitae;Namgoong, Jeongil;Yie, Ikkwon
    • Korean Journal of Mathematics
    • /
    • 제22권3호
    • /
    • pp.517-527
    • /
    • 2014
  • In this paper, we study affine transformations of normal bases and give an explicit formulation of the multiplication table of an affine transformation of a normal basis. We then discuss constructions of self-dual normal bases using affine transformations of traces of a type I optimal normal basis and of a Gauss period normal basis.

단체법에서 효과적인 초기기저의 설정 (On the Construction of Initial Basis in the Simplex Method)

  • 임성묵;김기태;박순달
    • 경영과학
    • /
    • 제17권2호
    • /
    • pp.13-20
    • /
    • 2000
  • In this research, we compare and analyze the two initial basis construction procedures: LPAKO’s procedure proposed by Seo et. al. and symbolic crash procedure proposed by Maros et. al.. Based on the analysis, we present a new procedure which complements the previous procedures. The new procedure shows superiority to the previous procedures with respects to the optimality of initial basis. Also, the linear basis Also. the initial basis constructed by the new procedure reduces the number of simplex iterations.

  • PDF

적응적 성분분석 기법에 의한 RBF 신경망의 성능개선 (Performance Improvement of Radial Basis Function Neural Networks Using Adaptive Principal Component Analysis)

  • 조용현;윤중환
    • 한국정보과학회:학술대회논문집
    • /
    • 한국정보과학회 2000년도 봄 학술발표논문집 Vol.27 No.1 (B)
    • /
    • pp.475-477
    • /
    • 2000
  • 본 논문에서는 적응적 성분분석 기법을 이용하여 radial basis 함수 신경망의 학습시간과 분류성능을 개선한 새로운 기법을 제안하였다. 제안된 기법에서 적응적 성분분석 기법은 radial basis 함수 신경망의 은닉층 뉴런 개수와 중심값 설정을 위해 이용하였다. 제안된 기법의 radial basis 함수 신경망을 200명의 암환자를 2부류(초기와 악성)로 분류하는 문제에 적용하여 시뮬레이션한 결고, k-평균 군집화 알고리즘을 이용한 radial basis 함수 신경망과 비교할 때 학습시간과 시험 데이터의 분류에서 더욱 우수한 성능이 있음을 확인할 수 있었다.

  • PDF

EFFICIENT PARALLEL GAUSSIAN NORMAL BASES MULTIPLIERS OVER FINITE FIELDS

  • Kim, Young-Tae
    • 호남수학학술지
    • /
    • 제29권3호
    • /
    • pp.415-425
    • /
    • 2007
  • The normal basis has the advantage that the result of squaring an element is simply the right cyclic shift of its coordinates in hardware implementation over finite fields. In particular, the optimal normal basis is the most efficient to hardware implementation over finite fields. In this paper, we propose an efficient parallel architecture which transforms the Gaussian normal basis multiplication in GF($2^m$) into the type-I optimal normal basis multiplication in GF($2^{mk}$), which is based on the palindromic representation of polynomials.