Partial circle geometries and antiregular quadrangles

In this chapter, a partial circle ground textile patch antenna for wideband applications with better bandwidth is presented. The simulated antenna is proposed on textile jeans substrate having dielectric constant of 1.7. The radius of textile jeans substrate antenna is 15 mm. The overall simulation of partial circle grounded shaped antenna has been done using CST simulation tool. The simulated antenna resonates at frequency 9.285 GHz with the reflection coefficient of -28 dB. It covers a bandwidth from 7.008 GHz to 9.64 GHz. It has maximum directivity of 4.540 dBi.

The Case for the Rectangular/Trapezoidal Orchestra

Theatre Research International ◽

10.1017/s030788330001419x ◽

1988 ◽

Vol 13 (1) ◽

pp. 1-20 ◽

Cited By ~ 3

Author(s):

Clifford Ashby

Keyword(s):

Fourth Century ◽

Partial Circle

In 1947, Carlo Anti publishedTeatri Greci Arcaici da Minosse a Pericle. In this book, he formulated what one reviewer termed ‘the dogma of the originally rectangular orchestra’. This directly contradicted over a century of research which had concluded that Greek performance areas began with a completely circular dancing place and gradually changed to an arrangement which used a partial circle backed by a scene house. Over a hundred part-circular orchestras, lastingly embalmed in stone, attest to the accuracy of at least part of this curvilinear hypothesis. All of these stone remains, however, are from the mid-fourth century or later; nothing remains of the wooden theatres in which the plays of Aeschylus, Sophocles, Euripides, and Aristophanes were first performed.

D-optimal designs for combined polynomial and trigonometric regression on a partial circle

Journal of Statistical Planning and Inference ◽

10.1016/j.jspi.2013.01.013 ◽

2013 ◽

Vol 143 (7) ◽

pp. 1186-1194

Author(s):

Fu-Chuen Chang ◽

Chin-Han Li

Keyword(s):

Optimal Designs ◽

Trigonometric Regression ◽

Partial Circle

A Novel Arc Segmentation Approach for Document Image Processing

International Journal of Pattern Recognition and Artificial Intelligence ◽

10.1142/s0218001415530018 ◽

2015 ◽

Vol 29 (01) ◽

pp. 1553001 ◽

Cited By ~ 1

Author(s):

Zili Zhang ◽

Xuan Wang ◽

Kai Han ◽

Zoe L. Jiang

Keyword(s):

Image Processing ◽

Document Image ◽

Large Radius ◽

Circle Fitting ◽

Evaluation Tool ◽

Document Image Processing ◽

Segmentation Approach ◽

Average Distribution ◽

Seed Points ◽

Partial Circle

In document image processing, arc segmentation plays an important role in vectorization and graphic recognition. Moreover, the unsatisfactory results of several recent arc segmentation contests indicate that conventional methods are inadequate. This paper proposes a new arc segmentation algorithm called SymCAve (an acronym for Symmetry axis, Circle fitting and Average distribution points). First, we locate several seed points and adopt three strategies to ensure that the seed points are proper; then we calculate the center and radius utilizing the seed points. Second, the coordinates of the center and radius are adjusted by employing symmetry axes. Third, the average distribution points method is used to verify whether the points on the circumference are all black pixels. It is a complete circle if all of the points are black pixels. Otherwise, it is a partial circle if some of the points are black pixels and are continuous. Based on this information, the start and end angles of the partial circle can be determined. Finally, these arcs are verified to ensure that the results are accurate. Images and the evaluation tool were obtained from the GREC Workshop's Arc Segmentation contests, to test the systematic performance of the SymCAve algorithm. The experiments demonstrate that the proposed method can provide promising results. However, the algorithm has some drawbacks: it cannot detect a line with width of one pixel, small angles, and any large radius arcs. It is suited for segmenting images with appropriate symmetry axes.

A functional-algebraic determination of D-optimal designs for trigonometric regression models on a partial circle

Statistics & Probability Letters ◽

10.1016/s0167-7152(02)00152-9 ◽

2002 ◽

Vol 58 (4) ◽

pp. 389-397 ◽

Cited By ~ 7

Author(s):

Holger Dette ◽

Viatcheslav B. Melas ◽

Stefanie Biedermann

Keyword(s):

Regression Models ◽

Optimal Designs ◽

Trigonometric Regression ◽

Partial Circle

Exact $$D$$ -optimal designs for first-order trigonometric regression models on a partial circle

Metrika ◽

10.1007/s00184-012-0420-x ◽

2012 ◽

Vol 76 (6) ◽

pp. 857-872 ◽

Cited By ~ 6

Author(s):

Fu-Chuen Chang ◽

Lorens Imhof ◽

Yi-Ying Sun

Keyword(s):

Regression Models ◽

Optimal Designs ◽

First Order ◽

Trigonometric Regression ◽

Partial Circle