The existing results of curve degree elevation mainly focus on the degree of algebraic polynomials. The paper considers the elevation of degree of the trigonometric polynomial, from a Bezier curve on the algebraic pol...The existing results of curve degree elevation mainly focus on the degree of algebraic polynomials. The paper considers the elevation of degree of the trigonometric polynomial, from a Bezier curve on the algebraic polynomial space, to a C-Bezier curve on the algebraic and trigonometric polynomial space. The matrix of degree elevation is obtained by an operator presentation and a derivation pyramid. It possesses not a recursive presentation but a direct expression. The degree elevation process can also be represented as a corner cutting form.展开更多
In this note we prove that the corner cutting procedure preserves continuityproperties,i.e.,a sequence of polygons obtained in this way belongs to the Lipschitz classof the same constant and exponent.As a consequence ...In this note we prove that the corner cutting procedure preserves continuityproperties,i.e.,a sequence of polygons obtained in this way belongs to the Lipschitz classof the same constant and exponent.As a consequence this also holds for all functions orcurves obtained as the limit of this procedure, such as the Bernstein polynomials,Bezierand spline parametric curves,etc.展开更多
A ceramic dielectric resonator antenna excited by a corner-cut square patch for the circularly-polarized operation is introduced. The effect of patch size and cut size is investigated, showing that the resonant freque...A ceramic dielectric resonator antenna excited by a corner-cut square patch for the circularly-polarized operation is introduced. The effect of patch size and cut size is investigated, showing that the resonant frequency of the antenna can be changed by simply changing the patch size. The reflection, axial ratio, and radiation characteristics of the antenna are found. Measurements were carried out to verify the design. The antenna is compact in structure, which is attractive in the application as the satellite communication terminals.展开更多
基金Supported by the National Natural Science Foundation of China(61402201,11326243,61272300,11371174)the Jiangsu Natural Science Foundation of China(BK20130117)
文摘The existing results of curve degree elevation mainly focus on the degree of algebraic polynomials. The paper considers the elevation of degree of the trigonometric polynomial, from a Bezier curve on the algebraic polynomial space, to a C-Bezier curve on the algebraic and trigonometric polynomial space. The matrix of degree elevation is obtained by an operator presentation and a derivation pyramid. It possesses not a recursive presentation but a direct expression. The degree elevation process can also be represented as a corner cutting form.
文摘In this note we prove that the corner cutting procedure preserves continuityproperties,i.e.,a sequence of polygons obtained in this way belongs to the Lipschitz classof the same constant and exponent.As a consequence this also holds for all functions orcurves obtained as the limit of this procedure, such as the Bernstein polynomials,Bezierand spline parametric curves,etc.
基金Project supported by the National High-Technology Research and Development Project of China (Grant No.2007AA12Z125)the Innovation Foundation of Shanghai University (Grant No.SHUCX092130)
文摘A ceramic dielectric resonator antenna excited by a corner-cut square patch for the circularly-polarized operation is introduced. The effect of patch size and cut size is investigated, showing that the resonant frequency of the antenna can be changed by simply changing the patch size. The reflection, axial ratio, and radiation characteristics of the antenna are found. Measurements were carried out to verify the design. The antenna is compact in structure, which is attractive in the application as the satellite communication terminals.
