• Title/Summary/Keyword: exact methods

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Monotone Local Linear Quasi-Likelihood Response Curve Estimates

  • Park, Dong-Ryeon
    • Communications for Statistical Applications and Methods
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    • v.13 no.2
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    • pp.273-283
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    • 2006
  • In bioassay, the response curve is usually assumed monotone increasing, but its exact form is unknown, so it is very difficult to select the proper functional form for the parametric model. Therefore, we should probably use the nonparametric regression model rather than the parametric model unless we have at least the partial information about the true response curve. However, it is well known that the nonparametric regression estimate is not necessarily monotone. Therefore the monotonizing transformation technique is of course required. In this paper, we compare the finite sample properties of the monotone transformation methods which can be applied to the local linear quasi-likelihood response curve estimate.

A FAST TEMPLATE MATCHING METHOD USING VECTOR SUMMATION OF SUBIMAGE PROJECTION

  • Kim, Whoi-Yul;Park, Yong-Sup
    • Proceedings of the Korean Society of Broadcast Engineers Conference
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    • 1999.06a
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    • pp.171-176
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    • 1999
  • Template matching is one of the most often used techniques for machine vision applications to find a template of size M$\times$M or subimage in a scene image of size N$\times$N. Most template matching methods, however, require pixel operations between the template and the image under analysis resulting in high computational cost of O(M2N2). So in this thesis, we present a two stage template matching method. In the first stage, we use a novel low cost feature whose complexity is approaching O(N2) to select matching candidates. In the second stage, we use conventional template matching method to find out the exact matching point. We compare the result with other methods in terms of complexity, efficiency and performance. Proposed method was proved to have constant time complexity and to be quite invariant to noise.

A Study On Preprocessing of Fingerprint Image Using Multi-Scale Roof Edges (다척도 지붕에지 검출방법을 이용한 지문영상의 전처리에 대한 연구)

  • Kim Soo Gyeam
    • Journal of Advanced Marine Engineering and Technology
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    • v.29 no.2
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    • pp.217-224
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    • 2005
  • A new roof edge detection method based on multi level scales of wavelet function is proposed in this paper roof edge and its direction are obtained in this new methods at one time. Besides. scale characteristics of detecting roof edge is analyzed. And a few new methods on fingerprint image pre-processing are described. A method segmenting foreground/background of fingerprint images is proposed, in which Prior estimation of direction field is not required any more. A segmentation method based on multi-scale roof edges is implemented. and the valid scale range of the method is defined. too. And the method is used to segment ridges and valleys in fingerprint images simultaneously The exact direction fields made up of the direction of each point in ridges can be obtained when detecting ridges exactly based on the roof edge detector, in comparison with the traditional coarse estimation of direction fields. Obviously. it will establish a solid foundation for the sequent fingerprint identification.

The study on the multi-mode muffler by intelligent control for low noise and low backpressure (저소음 저배압을 위한 다중모드 지능제어 배기계에 관한 연구 -음향관 모델의 모델차수 결정방법-)

  • 손동구;김흥섭;오재응
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 1996.10a
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    • pp.142-147
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    • 1996
  • For prediction and control of sound, acoustic systems must be modeled. Because sound systems like exhaust systems are very difficult to calculate mathematically, this study presents a method to determine experimentally the order of poles by transfer function. When designing a control system by traditional methods the exact model order and coefficient of the system to be controlled must be determined. But in acoustic systems, where systems to be controlled are very complex, mathematical interpretation is almost always impossible. Therefore transversal filters using trial and error methods to determine model order of a system are used to design a system. Compared to mathematical models with poles, transversal filters, in which the model order becomes relatively large, have the disadvantage of prolonged processing time and marked time delay. This study presents a method to determine experimentally the order of poles in a system model with poles and zeroes. Also, the validity of this method was verified mathematically and confirmed by application in general simple models and acoustic tube simulators.

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Virtual boundary element-equivalent collocation method for the plane magnetoelectroelastic solids

  • Yao, Wei-An;Li, Xiao-Chuan;Yu, Gui-Rong
    • Structural Engineering and Mechanics
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    • v.22 no.1
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    • pp.1-16
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    • 2006
  • This paper presents a virtual boundary element-equivalent collocation method (VBEM) for the plane magnetoelectroelastic solids, which is based on the fundamental solutions of the plane magnetoelectroelastic solids and the basic idea of the virtual boundary element method for elasticity. Besides all the advantages of the conventional boundary element method (BEM) over domain discretization methods, this method avoids the computation of singular integral on the boundary by introducing the virtual boundary. In the end, several numerical examples are performed to demonstrate the performance of this method, and the results show that they agree well with the exact solutions. So the method is one of the efficient numerical methods used to analyze megnatoelectroelastic solids.

An improved Rankine source panel method for three dimensional water wave problems

  • Feng, Aichun;You, Yunxiang;Cai, Huayang
    • International Journal of Naval Architecture and Ocean Engineering
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    • v.11 no.1
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    • pp.70-81
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    • 2019
  • An improved three dimensional Rankine source method is developed to solve numerically water wave problems in time domain. The free surface and body surface are both represented by continuous panels rather than a discretization by isolated points. The integral of Rankine source 1/r on free surface panel is calculated analytically instead of numerical approximation. Due to the exact algorithm of Rankine source integral applied on the free surface and body surface, a space increment free surface source distribution method is developed and much smaller amount of source panels are required to cover the fluid domain surface than other numerical approximation methods. The proposed method shows a higher accuracy and efficiency compared to other numerical methods for various water wave problems.

Evaluation of Average Shear-wave Velocity Estimation Methods of Multi-layered Strata Considering Site Period (지반주기를 고려한 다층지반의 평균전단파속도 추정 방법 평가)

  • Kim, Dong-Kwan
    • Journal of the Earthquake Engineering Society of Korea
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    • v.23 no.3
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    • pp.191-199
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    • 2019
  • To calculate proper seismic design load and seismic design category, the exact site class for construction site is required. At present, the average shear-wave velocity for multi-layer soil deposits is calculated by the sum of shear-wave velocities without considering of vertical relationship of the strata. In this study, the transfer function for the multi-layered soil deposits was reviewed on the basis of the wave propagation theory. Also, the transfer function was accurately verified by the finite element model and the eigenvalue analysis. Three methods for site period estimation were evaluated. The sum of shear-wave velocities underestimated the average shear-wave velocities of 526 strata with large deviations. The equation of Mexican code overestimated the average shear-wave velocities. The equation of Japanese code well estimated the average shear-wave velocities with small deviation.

Heat Transfer Analysis in a Straight Fin of Trapezoidal Profile by the Heat Balance Integral Method (열평형적분법에 의한 사다리꼴단면의 직선휜에서의 열전달해석)

  • Jo Jong-Chull;Cho Jin-Ho
    • The Magazine of the Society of Air-Conditioning and Refrigerating Engineers of Korea
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    • v.11 no.3
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    • pp.1-8
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    • 1982
  • When exact analytical solutions to certain type of heat conduction problems are quite cumbersome or not obtainable, it is important to introduce approximate analytical methods which are simple and useful compared with numerical methods. In this study, therefore, the Heat Balance Integral Method is applied to analysis of steady-state conduction in a straight fin of trapezoidal profile, and the two-dimensional temperature distribution in the fin and the approximate fin efficiency are obtained. Results are compared with those by the one- dimensional analysis and two-dimensional numerical analysis for a wide range of Biot numbers. It is shown that the two-dimensional temperature distribution obtained by the integral method is in good agreement with that by the finite element method at Biot numbers for which the result by the one-dimensional analysis is unreliable.

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Free vibration analysis of FG carbon nanotube reinforced composite plates using dynamic stiffness method

  • Shahabeddin Hatami;Mohammad Reza Bahrami
    • Steel and Composite Structures
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    • v.50 no.2
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    • pp.135-148
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    • 2024
  • This paper analytically investigates the free vibration analysis of functionally graded-carbon nanotube reinforced composite (FG-CNTRC) plates by dynamic stiffness method (DSM). The properties of CNTRC are determined with the extended rule of mixture. The governing differential equations of motion based on the first-order shear deformation theory of CNTRC plate are derived using Hamilton's principle. The FG-CNTRC plates are studied for a uniform and two different distributions of carbon nanotubes (CNTs). The accuracy and performance of the DSM are compared with the results obtained from closed closed-form and semi-analytical solution methods in previous studies. In this study, the effects of boundary condition, distribution type of CNTs, plate aspect ratio, plate length to thickness ratio, and different values of CNTs volume fraction on the natural frequencies of the FG-CNTRC plates are investigated. Finally, various natural frequencies of the plates in different conditions are provided as a benchmark for comparing the accuracy and precision of the other analytical and numerical methods.

An accurate analytical exploration for dynamic response of thermo-electric CNTRC beams under driving harmonic and constant loads resting on Pasternak foundation

  • Mohammadreza Eghbali;Seyed Amirhosein Hosseini
    • Advances in nano research
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    • v.16 no.6
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    • pp.549-564
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    • 2024
  • This paper aims to analyze the dynamic response of thermoelectric carbon nanotube-reinforced composite (CNTRC) beams under moving harmonic load resting on Pasternak elastic foundation. The governing equations of thermoelectric CNTRC beam are obtained based on the Karama shear deformation beam theory. The beams are resting on the Pasternak foundation. Previous articles have not performed the moving load mode with the analytical method. The exact solution for the transverse and axial dynamic response is presented using the Laplace transform. A comparison of previous studies has been published, where a good agreement is observed. Finally, some examples were used to analyze, such as excitation frequency, voltage, temperature, spring constant factors, the volume fraction of Carbon nanotubes (CNTs), the velocity of a moving harmonic load, and their influence on axial and transverse dynamic and maximum deflections. The advantages of the proposed method compared to other numerical methods are zero reduction of the error percentage that exists in numerical methods.