• Title/Summary/Keyword: and Three-point method

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Vanishing Point Detection Method Using Multiple Initial Vanishing Points (다중 초기 소실점을 이용한 소실점 검출 방법)

  • Lee, Chang-Hyung;Choi, Hyung-Il
    • The Journal of the Korea Contents Association
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    • v.18 no.2
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    • pp.231-239
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    • 2018
  • In this paper, we propose a vanishing point detection method using multiple initial vanishing points. Vanishing points are important geometric information that is used for reconstructing 3D structures. Three vanishing points are detected for indoor scenes. In the previous work, it could be inaccurate to detect only one initial vanishing point, because initial vanishing point getting most highest sum of voting could be deferent from the best initial vanishing point. Therefore the method which sets multiple initial vanishing point and detects a best vanishing point from them gives us preparation for the prior case. Also in this paper, we propose a adjusting vanishing point method by postprocessing of detected vanishing points. We could detect more accurate vanishing point by using postprocessing. Experimental results show that the accuracy of the vanishing point detection is about 1~2% higher than that of the existing method through the proposed method and the performance is improved accordingly.

Bounding volume estimation algorithm for image-based 3D object reconstruction

  • Jang, Tae Young;Hwang, Sung Soo;Kim, Hee-Dong;Kim, Seong Dae
    • IEIE Transactions on Smart Processing and Computing
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    • v.3 no.2
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    • pp.59-64
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    • 2014
  • This paper presents a method for estimating the bounding volume for image-based 3D object reconstruction. The bounding volume of an object is a three-dimensional space where the object is expected to exist, and the size of the bounding volume strongly affects the resolution of the reconstructed geometry. Therefore, the size of a bounding volume should be as small as possible while it encloses an actual object. To this end, the proposed method uses a set of silhouettes of an object and generates a point cloud using a point filter. A bounding volume is then determined as the minimum sphere that encloses the point cloud. The experimental results show that the proposed method generates a bounding volume that encloses an actual object as small as possible.

Design of Optimal Locating Point of the Hydraulic Cylinder Actuating a Roller-Link Type Rotating Floodgate (콤플렉스법에 의한 롤러-링크 부착형 전도수문 구동용 유압실린더의 최적 설치점 설계)

  • Lee, S.R.
    • Journal of Drive and Control
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    • v.9 no.3
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    • pp.29-36
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    • 2012
  • The hydraulic cylinder is used for actuating the roller-link type rotating floodgate which controls the volume of water in the reservoir. The locating points of hydraulic cylinder are restricted to the limited space and determined to minimize the cylinder force necessary for actuating the floodgate. Generally, the head end point of cylinder is fixed at underground and the rod end point of cylinder is connected to the support link. Therefore there exist three design variables to be determined to minimize the cylinder force within the rotating range of floodgate. First, the mathematical model of the roller-link type rotating floodgate is derived to find the cylinder force corresponding to the floodgate angle. Then, the optimal locating point of hydraulic cylinder is searched using the complex method that is one kind of constrained direct search method.

A Fast Search Algorithm for Sub-Pixel Motion Estimation (부화소 움직임 추정을 위한 고속 탐색 기법)

  • Park, Dong-Kyun;Jo, Seong-Hyeon;Cho, Hyo-Moon;Lee, Jong-Hwa
    • Proceedings of the KIEE Conference
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    • 2007.04a
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    • pp.26-28
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    • 2007
  • The motion estimation is the most important technique in the image compression of the video standards. In the case of next generation standards in the video codec as H.264, a high compression-efficiency can be also obtained by using a motion compensation. To obtain the accurate motion search, a motion estimation should be achieved up to 1/2 pixel and 1/4 pixel uiuts. To do this, the computational complexity is increased although the image compression rate is increased. Therefore, in this paper, we propose the advanced sub-pixel block matching algorithm to reduce the computational complexity by using a statistical characteristics of SAD(Sum of Absolute Difference). Generally, the probability of the minimum SAD values is high when searching point is in the distance 1 from the reference point. Thus, we reduced the searching area and then we can overcome the computational complexity problem. The main concept of proposed algorithm, which based on TSS(Three Step Search) method, first we find three minimum SAD points which is in integer distance unit, and then, in second step, the optimal point is in 1/2 pixel unit either between the most minimum SAD value point and the second minimum SAD point or between the most minimum SAD value point and the third minimum SAD point In third step, after finding the smallest SAD value between two SAD values on 1/2 pixel unit, the final optimized point is between the most minimum SAD value and the result value of the third step, in 1/2 pixel unit i.e., 1/4 pixel unit in totally. The conventional TSS method needs an eight.. search points in the sub-pixel steps in 1/2 pixel unit and also an eight search points in 1/4 pixel, to detect the optimal point. However, in proposed algorithm, only total five search points are needed. In the result. 23 % improvement of processing speed is obtained.

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A Model Study for Electrical Resistivity Method Using Three-Point Electrode Array (Three-Point 전극(電極) 배열법(配列法)을 이용(利用)한 전기(電氣) 비저항탐사(比抵抗探査) 모형연구(模型硏究))

  • Min, Kyung Duck;Kim, Chong Mi
    • Economic and Environmental Geology
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    • v.14 no.3
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    • pp.111-122
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    • 1981
  • This study is a model analysis for an effective application of the geophysical prospecting to the investigation of geological structures or useful resources, and the purpose of it is to research a property of the electrical resistivity prospecting, especially by using a Three-Point electrode array method. In using the Three-Point electrode array method, it is theoretically assumed to choose the infinite for a distance between the two current electrodes, however it is impossible in applying to the practical field prospecting. Therefore this study was conducted for determination and presentation of a minimum appropriate distance between the two current electrodes by making a study on prospecting effect in the variation of distance between both the electrodes. In case that the ratios of the distance between the two current electrodes to that between the two potential electrodes are respectively chosen for 40, 400, 5,000, the experimental data of this study showed that the minimum appropriate distance between the two current electrodes is forty times as much as that between two potential electrodes. In order to make clear a problem about prospecting depth which is essential to the data processing, it had been chosen equally to the distance between two potential electrodes. As a result of it, it was shown that the anomaly is appeared along the position of an assumed ore body. Consequently it was found out that the prospecting depth of the Three-Point electrode array method is the same as the distance between the two potential electrodes. From the model experiment on the sheeting ore body(or linear structure) of horizontal, dipping of $30^{\circ}$, $60^{\circ}$ and vertical on the basis of above experimental condition, it was found out that the position and dip of assumed ore body could be inferred from the aspects of the equiresistivity curve. In consequence of performing out the simultaneous Normal and Reversal electrode movement, it was shown that the electrode movement of the Reversal forms the anomaly more clearly than that of Normal when the sheeting ore body is situated obliquely, therefore it could be ascertained that the electrode movement have to be performed simultaneously in the manner of Normal and Reversal. It was also exhibited that the aspect of the equiresistivity curve forms symmetrically when an assumed ore body (or linear structure) is situated horizontally or vertically, that is, symmetrically, and moreover that the aspect of the equiresistivity curve forms unsymmetrically when an assumed ore body (or linear structure) is situated obliquely. On the basis of these experimental analysis it is thought that it can be inferred from the aspect of equiresistivity curve whether an assumed ore body is obliquely situated or not.

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A discrete particle model for reinforced concrete fracture analysis

  • Azevedo, N. Monteiro;Lemos, J.V.;Almeida, J.R.
    • Structural Engineering and Mechanics
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    • v.36 no.3
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    • pp.343-361
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    • 2010
  • The Discrete Element Method adopting particles for the domain discretization has recently been adopted in fracture studies of non-homogeneous continuous media such as concrete and rock. A model is proposed in which the reinforcement is modelled by 1D rigid-spring discrete elements. The rigid bars interact with the rigid circular particles that simulate the concrete through contact interfaces. The DEM enhanced model with reinforcement capabilities is evaluated using three point bending and four point bending tests on reinforced concrete beams without stirrups. Under three point bending, the model is shown to reproduce the expected final crack pattern, the crack propagation and the load displacement diagram. Under four point bending, the model is shown to match the experimental ultimate load, the size effect and the crack propagation and localization.

Application of the Equivalent Point Method for Estimation of Kinetic Parameters (Kinetic Parameters 결정을 위한 Equivalent Point Method의 이용)

  • Rhim, Jong-Whan
    • Korean Journal of Food Science and Technology
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    • v.22 no.5
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    • pp.582-589
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    • 1990
  • A method for application of the equivalent time and temperature point for estimating kinetic parameters was proposed. The feasibility of the method was demonstrated with both theoretical and empirical kinetic data. The theoretical kinetic data were obtained from the arbitrarily chosen time-temperature data for three chemical reactions whose kinetics are well established. The experimental kinetic data were obtained for the acid (0.0005 N HCl) catalyzed hydrolysis of sucrose(2%). The activation energy and the frequency factor determined by the proposed method were $104.74{\pm}1.87kJ/mol\;and\;5.62{\times}10^{14}\;hr^{-1}$ respectively and the results agreed well with those obtained by a different method of kinetic parameter estimation, i.e. the linearly increasing temperature method.

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STRONG CONVERGENCE THEOREMS OF COMMON ELEMENTS FOR EQUILIBRIUM PROBLEMS AND FIXED POINT PROBLEMS IN BANACH SPACES

  • Wang, Ziming;Su, Yongfu
    • Journal of applied mathematics & informatics
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    • v.28 no.3_4
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    • pp.783-796
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    • 2010
  • We introduce a new iterative algorithm for equilibrium and fixed point problems of three hemi-relatively nonexpansive mappings by the CQ hybrid method in Banach spaces, Our results improve and extend the corresponding results announced by Xiaolong Qin, Yeol Je Cho, Shin Min Kang [Xiaolong Qin, Yeol Je Cho, Shin Min Kang, Convergence theorems of common elements for equilibrium problems and fixed point problems in Banach spaces, Journal of Computational and Applied Mathematics 225 (2009) 20-30], P. Kumam, K. Wattanawitoon [P. Kumam, K. Wattanawitoon, Convergence theorems of a hybrid algorithm for equilibrium problems, Nonlinear Analysis: Hybrid Systems (2009), doi:10.1016/j.nahs.2009.02.006], W. Takahashi, K. Zembayashi [W. Takahashi, K. Zembayashi, Strong convergence theorem by a new hybrid method for equilibrium problems and relatively nonexpansive mappings, Fixed Point Theory Appl. (2008) doi:10.1155/2008/528476] and others therein.

Non-destructive assessment of the three-point-bending strength of mortar beams using radial basis function neural networks

  • Alexandridis, Alex;Stavrakas, Ilias;Stergiopoulos, Charalampos;Hloupis, George;Ninos, Konstantinos;Triantis, Dimos
    • Computers and Concrete
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    • v.16 no.6
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    • pp.919-932
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    • 2015
  • This paper presents a new method for assessing the three-point-bending (3PB) strength of mortar beams in a non-destructive manner, based on neural network (NN) models. The models are based on the radial basis function (RBF) architecture and the fuzzy means algorithm is employed for training, in order to boost the prediction accuracy. Data for training the models were collected based on a series of experiments, where the cement mortar beams were subjected to various bending mechanical loads and the resulting pressure stimulated currents (PSCs) were recorded. The input variables to the NN models were then calculated by describing the PSC relaxation process through a generalization of Boltzmannn-Gibbs statistical physics, known as non-extensive statistical physics (NESP). The NN predictions were evaluated using k-fold cross-validation and new data that were kept independent from training; it can be seen that the proposed method can successfully form the basis of a non-destructive tool for assessing the bending strength. A comparison with a different NN architecture confirms the superiority of the proposed approach.

Analyses and Measurements of Rotational Accuracy for Journal Shaft in a Scroll Compressor (스크롤 압축기 저어널 회전축의 궤적 계산 및 측정)

  • Park, Sang-Shin;Kim, Gyu-Ha;Lee, Jin-Kab
    • Tribology and Lubricants
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    • v.23 no.3
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    • pp.83-88
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    • 2007
  • This paper presents measurement processes of rotational accuracy and comparison of theoretical values in the main bearing of scroll compressor. The main bearing is a type of oil journal bearing, but it has an axial or helical groove. The generalized coordinate system method, which can handle this groove, is applied to calculate the pressure profile in the journal bearing. The orbits of journal shaft are calculated corresponding to the compressed gas forces and bearing reaction forces. Then, the orbits are measured using three-point method. The results are compared to that from analyses.