A class of quasi-cubic B-spline base functions by trigonometric polynomials are established which inherit properties similar to those of cubic B-spline bases. The corresponding curves with a shape parameter a, defined...A class of quasi-cubic B-spline base functions by trigonometric polynomials are established which inherit properties similar to those of cubic B-spline bases. The corresponding curves with a shape parameter a, defined by the introduced base functions, include the B-spline curves and can approximate the B-spline curves from both sides. The curves can be adjusted easily by using the shape parameter a, where dpi(a,t) is linear with respect to da for the fixed t. With the shape parameter chosen properly, the defined curves can be used to precisely represent straight line segments, parabola segments, circular arcs and some transcendental curves, and the corresponding tensor product surfaces can also represent spherical surfaces, cylindrical surfaces and some transcendental surfaces exactly. By abandoning positive property, this paper proposes a new C^2 continuous blended interpolation spline based on piecewise trigonometric polynomials associated with a sequence of local parameters. Illustration showed that the curves and surfaces constructed by the blended spline can be adjusted easily and freely. The blended interpolation spline curves can be shape-preserving with proper local parameters since these local parameters can be considered to be the magnification ratio to the length of tangent vectors at the interpolating points. The idea is extended to produce blended spline surfaces.展开更多
Newton's polynomial interpolation may be the favorite linear interpolation,associated continued fractions interpolation is a new type nonlinear interpolation.We use those two interpolation to construct a new kind of ...Newton's polynomial interpolation may be the favorite linear interpolation,associated continued fractions interpolation is a new type nonlinear interpolation.We use those two interpolation to construct a new kind of bivariate blending rational interpolants.Characteristic theorem is discussed.We give some new blending interpolation formulae.展开更多
Objective To evaluate the feasibility of the Shikani Optical Stylet (SOS)-guided inmbation through a new Intubafing Laryngeal Airway (ILA) in anticipated difficult airways caused by scar contracture of the face an...Objective To evaluate the feasibility of the Shikani Optical Stylet (SOS)-guided inmbation through a new Intubafing Laryngeal Airway (ILA) in anticipated difficult airways caused by scar contracture of the face and neck. Methods Thirty-three adult patients with anticipated difficult airways undergoing selective faciocervical scar plastic surgery under general anesthesia were enrolled in this study. After anesthesia induction, a size 2.5, 3.5 or 4.5 ILA was inserted. Following good lung ventilation being verified, the SOS preloaded with an endotracheal tube was inserted via the ILA. Once the clear vocal cords came into view under the SOS, the endotracheal tube was advanced through glottis into the trachea. Results The ILA provided an effective airway in all patients, lntubation was successful at the first attempt on 22/33 (66.7%) occasions and at the second attempt on 6/33 (18.2%). Intubation failed in 5 (15.1%) patients who suffered from severe limitation of head extension due to scar contracture of the neck. These patients' tracheas were finally intubated using a fibreoptic bronchoscope via the ILA. Conclusions The SOS-guided intubating method via the ILA is a feasible technique in patients with scar contracture of the face and neck. However, in patients with severe limitation of head extension, the use of SOS cannot be recommended. The SOS can be used as an alternative apparatus when the fibreoptic bronchoscope is not available.展开更多
In this paper, we propose a highly automatic approach for 3D photorealistic face reconstruction from a single frontal image. The key point of our work is the implementation of adaptive manifold learning approach. Befo...In this paper, we propose a highly automatic approach for 3D photorealistic face reconstruction from a single frontal image. The key point of our work is the implementation of adaptive manifold learning approach. Beforehand, an active appearance model (AAM) is trained for automatic feature extraction and adaptive locally linear embedding (ALLE) algorithm is utilized to reduce the dimensionality of the 3D database. Then, given an input frontal face image, the corresponding weights between 3D samples and the image are synthesized adaptively according to the AAM selected facial features. Finally, geometry reconstruction is achieved by linear weighted combination of adaptively selected samples. Radial basis function (RBF) is adopted to map facial texture from the frontal image to the reconstructed face geometry. The texture of invisible regions between the face and the ears is interpolated by sampling from the frontal image. This approach has several advantages: (1) Only a single frontal face image is needed for highly automatic face reconstruction; (2) Compared with former works, our reconstruction approach provides higher accuracy; (3) Constraint based RBF texture mapping provides natural appearance for reconstructed face.展开更多
基金Project supported by the National Natural Science Foundation of China (Nos. 10171026 and 60473114), the Research Funds forYoung Innovation Group, Education Department of Anhui Prov-ince (No. 2005TD03) and the Natural Science Foundation of An-hui Provincial Education Department (No. 2006KJ252B), China
文摘A class of quasi-cubic B-spline base functions by trigonometric polynomials are established which inherit properties similar to those of cubic B-spline bases. The corresponding curves with a shape parameter a, defined by the introduced base functions, include the B-spline curves and can approximate the B-spline curves from both sides. The curves can be adjusted easily by using the shape parameter a, where dpi(a,t) is linear with respect to da for the fixed t. With the shape parameter chosen properly, the defined curves can be used to precisely represent straight line segments, parabola segments, circular arcs and some transcendental curves, and the corresponding tensor product surfaces can also represent spherical surfaces, cylindrical surfaces and some transcendental surfaces exactly. By abandoning positive property, this paper proposes a new C^2 continuous blended interpolation spline based on piecewise trigonometric polynomials associated with a sequence of local parameters. Illustration showed that the curves and surfaces constructed by the blended spline can be adjusted easily and freely. The blended interpolation spline curves can be shape-preserving with proper local parameters since these local parameters can be considered to be the magnification ratio to the length of tangent vectors at the interpolating points. The idea is extended to produce blended spline surfaces.
基金Supported by the Project Foundation of the Department of Education of Anhui Province(KJ2008A027,KJ2010B182,KJ2011B152,KJ2011B137)Supported by the Grant of Scientific Research Foundation for Talents of Hefei University(11RC05)Supported by the Grant of Scientific Research Foundation Hefei University(11KY06ZR)
文摘Newton's polynomial interpolation may be the favorite linear interpolation,associated continued fractions interpolation is a new type nonlinear interpolation.We use those two interpolation to construct a new kind of bivariate blending rational interpolants.Characteristic theorem is discussed.We give some new blending interpolation formulae.
文摘Objective To evaluate the feasibility of the Shikani Optical Stylet (SOS)-guided inmbation through a new Intubafing Laryngeal Airway (ILA) in anticipated difficult airways caused by scar contracture of the face and neck. Methods Thirty-three adult patients with anticipated difficult airways undergoing selective faciocervical scar plastic surgery under general anesthesia were enrolled in this study. After anesthesia induction, a size 2.5, 3.5 or 4.5 ILA was inserted. Following good lung ventilation being verified, the SOS preloaded with an endotracheal tube was inserted via the ILA. Once the clear vocal cords came into view under the SOS, the endotracheal tube was advanced through glottis into the trachea. Results The ILA provided an effective airway in all patients, lntubation was successful at the first attempt on 22/33 (66.7%) occasions and at the second attempt on 6/33 (18.2%). Intubation failed in 5 (15.1%) patients who suffered from severe limitation of head extension due to scar contracture of the neck. These patients' tracheas were finally intubated using a fibreoptic bronchoscope via the ILA. Conclusions The SOS-guided intubating method via the ILA is a feasible technique in patients with scar contracture of the face and neck. However, in patients with severe limitation of head extension, the use of SOS cannot be recommended. The SOS can be used as an alternative apparatus when the fibreoptic bronchoscope is not available.
基金Project supported by the National Natural Science Foundation of China (Nos. 60533090, 60525108)the National Basic Research Program (973) of China (No. 2002CB312101)+1 种基金the Science and Technology Project of Zhejiang Province, China (Nos. 2005C13032, 2005C11001-05)China-US Million Book Digital Library Project
文摘In this paper, we propose a highly automatic approach for 3D photorealistic face reconstruction from a single frontal image. The key point of our work is the implementation of adaptive manifold learning approach. Beforehand, an active appearance model (AAM) is trained for automatic feature extraction and adaptive locally linear embedding (ALLE) algorithm is utilized to reduce the dimensionality of the 3D database. Then, given an input frontal face image, the corresponding weights between 3D samples and the image are synthesized adaptively according to the AAM selected facial features. Finally, geometry reconstruction is achieved by linear weighted combination of adaptively selected samples. Radial basis function (RBF) is adopted to map facial texture from the frontal image to the reconstructed face geometry. The texture of invisible regions between the face and the ears is interpolated by sampling from the frontal image. This approach has several advantages: (1) Only a single frontal face image is needed for highly automatic face reconstruction; (2) Compared with former works, our reconstruction approach provides higher accuracy; (3) Constraint based RBF texture mapping provides natural appearance for reconstructed face.