Smooth point matching based on SIFT

Fabric shape style is one of the most important conditions in textile appearance evaluation, and also the main factor influences customer purchasing psychology. At first, the previous fabric shape style evaluation methods are classified and summarized, measurement and evaluation method discussed from tactic and dynamic aspects. Then, companied with computer vision principle, a non-contact method for measuring fabric shape style was put forward. In this method, two high-speed CCD cameras were used to capture fabric movement dynamically, fabric sequences image were obtained in this process. Used the image processing technology include pretreatment and feature point matching to get 3D motion parameters, it can provide data supports for shape style evaluation.

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Closed-Form Expressions for Numerical Evaluation of Self-Impedance Terms Involved on Wire Antenna Analysis by the Method of Moments

Electronics ◽

10.3390/electronics10111316 ◽

2021 ◽

Vol 10 (11) ◽

pp. 1316

Author(s):

Carlos-Ivan Paez-Rueda ◽

Arturo Fajardo ◽

Manuel Pérez ◽

Gabriel Perilla

Keyword(s):

Numerical Integration ◽

Method Of Moments ◽

Computing Time ◽

Basis Functions ◽

Wire Antenna ◽

Complex Geometries ◽

Point Matching ◽

Piecewise Constant ◽

Matching Procedure ◽

Time Required

This paper proposes new closed expressions of self-impedance using the Method of Moments with the Point Matching Procedure and piecewise constant and linear basis functions in different configurations, which allow saving computing time for the solution of wire antennas with complex geometries. The new expressions have complexity O(1) with well-defined theoretical bound errors. They were compared with an adaptive numerical integration. We obtain an accuracy between 7 and 16 digits depending on the chosen basis function and segmentation used. Besides, the computing time involved in the calculation of the self-impedance terms was evaluated and compared with the time required by the adaptative quadrature integration solution of the same problem. Expressions have a run-time bounded between 50 and 200 times faster than an adaptive numerical integration assuming full computation of all constant of the expressions.

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Line and point matching based on the maximum number of consecutive matching edge segment pairs for large viewpoint changing images

Signal Image and Video Processing ◽

10.1007/s11760-021-01959-6 ◽

2021 ◽

Author(s):

Luzi Wang ◽

Yunsheng Qian ◽

Xiangyu Kong

Keyword(s):

Point Matching ◽

Edge Segment

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Scene Wireframes Sketching for Drones

Proceedings ◽

10.3390/proceedings2181193 ◽

2018 ◽

Vol 2 (18) ◽

pp. 1193

Author(s):

Roi Santos ◽

Xose Pardo ◽

Xose Fdez-Vidal

Keyword(s):

State Of The Art ◽

Point Clouds ◽

Outdoor Environment ◽

Point Matching ◽

3D Point Clouds ◽

Complementary Approach ◽

Straight Line ◽

Scene Representation ◽

Feature Point Matching ◽

3D Scene

The increasing use of autonomous UAVs inside buildings and around human-made structures demands new accurate and comprehensive representation of their operation environments. Most of the 3D scene abstraction methods use invariant feature point matching, nevertheless some sparse 3D point clouds do not concisely represent the structure of the environment. Likewise, line clouds constructed by short and redundant segments with inaccurate directions limit the understanding of scenes as those that include environments with poor texture, or whose texture resembles a repetitive pattern. The presented approach is based on observation and representation models using the straight line segments, whose resemble the limits of an urban indoor or outdoor environment. The goal of the work is to get a full method based on the matching of lines that provides a complementary approach to state-of-the-art methods when facing 3D scene representation of poor texture environments for future autonomous UAV.

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The Bending, Buckling, and Flexural Vibration of Simply Supported Polygonal Plates by Point-Matching

Journal of Applied Mechanics ◽

10.1115/1.3641670 ◽

1961 ◽

Vol 28 (2) ◽

pp. 288-291 ◽

Cited By ~ 51

Author(s):

H. D. Conway

Keyword(s):

Hydrostatic Pressure ◽

Boundary Conditions ◽

Flexural Vibration ◽

Frequency Equation ◽

Numerical Results ◽

Special Technique ◽

Point Matching ◽

Buckling Loads ◽

Simply Supported ◽

Flexural Vibrations

The bending by uniform lateral loading, buckling by two-dimensional hydrostatic pressure, and the flexural vibrations of simply supported polygonal plates are investigated. The method of meeting the boundary conditions at discrete points, together with the Marcus membrane analog [1], is found to be very advantageous. Numerical examples include the calculation of the deflections and moments, and buckling loads of triangular square, and hexagonal plates. A special technique is then given, whereby the boundary conditions are exactly satisfied along one edge, and an example of the buckling of an isosceles, right-angled triangle plate is analyzed. Finally, the frequency equation for the flexural vibrations of simply supported polygonal plates is shown to be the same as that for buckling under hydrostatic pressure, and numerical results can be written by analogy. All numerical results agree well with the exact solutions, where the latter are known.

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