This paper presents a reconstruction algorithm to build a surface mesh approximating an object from an unorganized point sampling of the boundary object. It combines 3D Delaunay tetrahedralization and mesh-growing method and uses only once Delaunay triangulation. It begins with 3D Delaunay triangulation of the sampling. Then initialize the surface mesh with seed facets selected from Delaunay triangulation. Selection is based on the angle formed by the circumscribing ball of incident tetrahedral. Finally, grow until complete the surface mesh based on some heuristic rules. This paper shows several experimental results that demonstrate this method can handle open and close surfaces and work efficiently on various object topologies except non-manifold surface with self-intersections. It can reproduce even the smallest details of well-sampled surfaces but not work properly in every under-sampled situation that point density is too low.
Compactly supported radial basis function can enable the coefficient matrix of solving weigh linear system to have a sparse banded structure,thereby reducing the complexity of the algorithm.Firstly,based on the compactly supported radial basis function,the paper makes the complex quadratic function(Multiquadric,MQ for short) to be transformed and proposes a class of compactly supported MQ function.Secondly,the paper describes a method that interpolates discrete motion capture data to solve the motion vectors of the interpolation points and they are used in facial expression reconstruction.Finally,according to this characteristic of the uneven distribution of the face markers,the markers are numbered and grouped in accordance with the density level,and then be interpolated in line with each group.The approach not only ensures the accuracy of the deformation of face local area and smoothness,but also reduces the time complexity of computing.
In computer graphic(CG),illumination rendering generated realistic effect at virtual scene is amazing.Not only plausible lighting effect is to show the relative position between of the objects,but also to reflect the material of visual appearance of the virtual objects.The diffuse-scene rendering reflectance credibility has gradually matured.Global illumination rendering method for the glossy material is still a challenge for the CG research.Because of the shiny materials is highly energy reflection between the complex light paths.Whether we trace glossy reflection paths,or use of one-reflection or multi-reflection approximate above complex illumination transmission is a difficult working.This paper we gather some commonly used global illumination algorithms recently year and its extension glossy scene improvements.And we introduce the limitation of classical algorithms rendering glossy scene and some extended solution.Finally,we will summarize the illumination rendering for specular scene,there are still some open problems.
We present a method that combines performance-driven method with segmented 3D blendshape models to animate a face.First we prepare key sample examples and corresponding key target examples.Next we segment the whole face into two regions,for each region we reduce dimensionality of source examples using PAC into abstract space which is defined by truncated PCA eigenvectors.Then for each example we fix the cardinal base function,which can determine the weight of the target example.Finally,in the animation stage we compute the weight of each example for each frame and add the weighted displacement vectors of each region on the general face model.
Photocatalysts with the photocatalytic"memory"effect could resolve the intrinsic activity loss of traditional photocatalysts when the light illumination is turned off.Due to the dual requirements of light absorption and energy storage/release functions,most previously reported photocatalysts with the photocatalytic"memory"effect were composite photocatalysts of two phase components,which may lose their performance due to gradually deteriorated interface conditions during their applications.In this work,a simple solvothermal process was developed to synthesize Bi2WO6 microspheres constructed by aggregated nanoflakes.The pure phase Bi_(2)WO_(6) was found to possess the photocatalytic"memory"effect through the trapping and release of photogenerated electrons by the reversible chemical state change of W component in the(WO_(4))^(2–)layers.When the illumination was switched off,Bi_(2)WO_(6) microspheres continuously produced H_(2)O_(2) in the dark as those trapped photogenerated electrons were gradually released to react with O_(2) through the two-electron O_(2) reduction process,resulting in the continuous disinfection of Escherichia coli bacteria in the dark through the photocatalytic"memory"effect.No deterioration of their cycling H2O2 production performance in the dark was observed,which verified their stable photocatalytic"memory"effect.
Weiyi YangYan ChenShuang GaoLicheng SangRuoge TaoCaixia SunJian Ku ShangQi Li
