基于半边折叠的三角网格模型分片参数化与重构算法

提出了一种三角网格模型参数化与重构算法,在网格分片参数化的基础上实规了模型三角面的半正规化重构.首先,使用考虑顶点权重和边长度的半边折叠方法把网格模型分层简化到基网格,在每次折叠操作的同时使用分片参数化方法把被删除顶点动态地映射到下层网格面上;然后,把基网格进行多次平面细分,利用原始网格顶点、参数化点和细分点之间的位置关系,对细分点进行扰动完成网格重构.实验结果表明,该算法能够得到特征保持的多分辨率简化模型,使用参数化结果重构的三角网格也能够较好地还原原始模型.     

Watermarking on 3D mesh based on spherical wavelet transform

INTRODUCTIONTherapidgrowthofdigitalmediaoverInternetprovideseverybodywiththefacilityofeasyaccess,copy,editanddistributionofdigitalcontentssuchaselectronicdocuments,images,soundsandvideos.Thereisurgentdemandfortechniquestoprotectthecopyrightoftheoriginaldigitaldataandtopreventunauthorizedduplicationortampering.Digitalwatermarkingordatahidingisonesolutionforthecopyrightprotectionofdigitaldata.Digitalwatermarkingisaprocessbywhichauser-specifiedsignal(watermark)ishiddenorembeddedintoanothersi…     

Watermarking on 3D mesh based on spherical wavelet transform

In this paper we propose a robust watermarking algorithm for 3D mesh. The algorithm is based on spherical wavelet transform. Our basic idea is to decompose the original mesh into a series of details at different scales by using spherical wavelet transform; the watermark is then embedded into the different levels of details. The embedding process includes: global sphere parameterization, spherical uniform sampling, spherical wavelet forward transform, embedding watermark, spherical wavelet inverse transform, and at last resampling the mesh watermarked to recover the topological connectivity of the original model. Experiments showed that our algorithm can improve the capacity of the watermark and the robustness of watermarking against attacks.     

三角网格模型的多分辨分析:方法和数据结构

提出了一个健壮有效的网格模型多分辨分析方法. 该方法面向任意网格模型且不需要具有子分连通性, 通过删除边和拆分点操作进行网格模型的向下采样和向上采样, 将网格模型表示为由一个低分辨率的网格和一系列修改操作组成的多分辨模型. 该算法在向下采样时, 重点考虑了简化误差对模型精度的影响, 在生成网格多分辨模型时, 将细化操作分解为对网格模型的几何修改信息和各细化操作之间的关系信息, 确保了多分辨网格模型的健壮性. 实验结果证明了本算法的有效性.     

图的符号边控制的若干下界

设G=(V,E)是一个非空图,一个函数f:E→{-1,1},如果满足∑e’∈N[e]f(e’)≥1对于每一条边e∈E(G)均成立,则称f为图G的一个符号边控制函数。图G的符号边控制数记为r’s(G),定义为r’s(G)=min{∑e∈E(G)f(e)︱f}为G的一个符号边控制函数。全文对图的符号边控制函数进行了研究,得到了图的符号边控制数的若干新的下界。     

A new algorithm of brain volume contours segmentation

This paper explores brain CT slices segmentation technique and some related problems, including contours segmentation algorithms, edge detector, algorithm evaluation and experimental results. This article describes a method for contour-based segmentation of anatomical structures in 3D medical data sets. With this method, the user manually traces one or more 2D contours of an anatomical structure of interest on parallel planes arbitrarily cutting the data set. The experimental results showed the segmentation based on 3D brain volume and 2D CT slices. The main creative contributions in this paper are: (1) contours segmentation algorithm; (2) edge detector; (3) algorithm evaluation. Project (No.69931010) supported by the National Natural Science Foundation of China     

一种改进的Sobel边缘检测和细化算法

提出了一种改进的Sobel边缘检测和细化算法,用8个方向的模板对灰度图像进行边缘检测得到粗边缘图像,将粗边缘图像再进行Sobel边缘检测得到新的边缘图像,将前者减去后者得到差值图,从而得到边缘较细的边缘图,对于边缘模糊的部分,这种过程可以重复多次,这样能够捕捉多个方向的边缘信息,使检测到的边缘和边缘细化定位更精确。该算法容易实现,计算量小,速度快,适合作为图像检测中的快速边缘检测及细化。     

Adaptive sampling for mesh spectrum editing

INTRODUCTION Free-form surface editing plays an importan part in geometric modeling, such as Free-Form De- formation (FFD), level of detail editing. Users need to be careful to avoid artifacts in the result surface. In this paper, we present a new mesh editing technique based on geometry signal wavelet analysis. It indi- rectly modifies vertex positions in spatial domain by the simple geometry proxy that is simplified from the original mesh, and performs filtering and enhance- ment in f…     

薄板连铸合金钢边裂原因分析

文章对本钢薄板坯连铸机低合金钢的生产出现的边裂原因进行分析,铸坯温度和[Nj、[Als]、[B]含量对成品卷边部裂纹有较大影响,通过改善冷却水工艺、合理控制[N]、[Als]、[B]含量,有效的减少了含B钢铸坯边部裂纹的产生。     

基于混沌映射的小波域自适应数字水印算法

提出一种基于混沌映射的小波域数字图像水印新算法。将含有版权信息的二值图像作为水印,利用两个混沌映射的切换得到一个混沌序列,用其对水印图像进行加密。并用二维混沌映射对嵌入位置进行加密。算法根据HVS特性得到嵌入点的局部掩模函数,实现了水印在原始图像小波域中的自适应嵌入。实验结果证明该算法具有良好的鲁棒性。     

C_(5m)×C_(5n)图的邻点可区别的边染色

设G是阶数不小于3的简单连通图,G的k-正常边染色称为是邻点可区别的,如果对G任意相邻两顶点关联边的颜色集合不同,则k中最小者称为是G的邻点可区别的边色数.本文证明了C5m×C5n的邻点可区别的边色数是5.     

The role of domain knowledge in creative generation

Previous studies have shown that a predominant tendency in creative generation tasks is to base new ideas on well-known, specific instances of previous ideas (e.g., basing ideas for imaginary aliens on dogs, cats or bears). However, a substantial minority of individuals has been shown to adopt more abstract approaches to the task and to develop more original products as a result. Because domain knowledge is sometimes thought to be associated with more abstract representations, it is possible that these individual differences are linked to how much people have learned about the domain in question. The present study explored the relationship between domain knowledge, the tendency to rely on specific domain instances and both the originality and practicality of outcomes in a task in which participants designed novel sports. In addition to designing novel sports, participants rated their own knowledge about and participation in sports, and they took a short test of sport knowledge. As in previous studies, there were individual differences in approaches to the task, and participants who relied on specific known sports (e.g., basketball) produced less original designs. Neither the measures of sport knowledge nor the measure of sport participation related to the tendency to rely on specific instances in developing the novel sports or to the originality of those creations. However, there were links between tested knowledge and the rated practicality of the designs.     

Stress field near an interface edge of linear hardening materials

The elastic-plastic singular stress field near an interface edge of bounded linear hardening material is substantially as same as that of bonded elastic materials whose Young's modulus and Poisson ratio are substituted by equivalent values, respectively. Further investigation by the elasto-plastic boundary element method (BEM) on the stress field near the interface edge showed that the stress field there can be divided into three regions: the domain region of the elastic-plastic singular stress field, the transitional region and the elastic region. The domain region of the elastic-plastic singular stress becomes larger with the increasing of the linear hardening coefficient. When the linear hardening coefficient decreases to a certain value, the effective stress in most of the yield zone equals approximately the yield stress. The stress distribution in the elastic region under small-scale yielding condition was also investigated. Project (No. 19972060) supported by the National Natural Science Foundation of China.     

A maximum a posteriori super resolution algorithm based on multidimensional Lorentzian distribution

This paper presents a threshold-free maximum a posteriori （MAP） super resolution （SR） algorithm to reconstruct high resolution （HR） images with sharp edges. The joint distribution of directional edge images is modeled as a multidimensional Lorentzian （MDL） function and regarded as a new image prior. This model makes full use of gradient information to restrict the solution space and yields an edge-preserving SR algorithm. The Lorentzian parameters in the cost function are replaced with a tunable variable, and graduated nonconvexity （GNC） optimization is used to guarantee that the proposed multidimensional Lor- entzian SR （MDLSR） algorithm converges to the global minimum. Simulation results show the effectiveness of the MDLSR algorithm as well as its superiority over conventional SR methods.     

论道德调整私人企业劳资关系的可行性

运用道德手段调节初级阶段我国私人企业的劳资关系具有现实的可行性。市场经济体制的建立和深化、完善为之提供了最深厚的宏观环境和社会支持，越来越尖锐化的私人企业劳资关系现状急切地呼唤以道德调整为主要途径和手段的新式管理理念，在理论与实践的结合和中外管理经验的交流互动领域里的新趋势则更进一步地例证了道德调整初级阶段我国私人企业劳资关系的紧迫性和现实性。     

形态学算子在图像处理中的应用

将腐蚀、膨胀算子经过有效组合,形成了一个性能优良的滤波算子,同时介绍了在冲击噪声的去噪中表现出显著效果的Extrema killer算子。提出了一种基于数学形态学的边缘检测算法,该算法先用一个较小尺度的结构元素进行腐蚀,后用一个较大尺度结构元素进行膨胀,用（fθB1） B2-f作为边缘检测算子。实验证明用所给算法进行图像边缘检测,能较好地保持图像的细节特征,同时能有效的抑制噪声。     

A new algorithm of brain volume contours segmentation

INTRODUCTIONSegmentation ,acentralissueofcomputervision ,isafundamentalprocessingstepinmostsystemsthatsupportmedicaldiagnosisorplan ningofsurgicaloperationsandradiationtreat ments (Wyattetal.,2 0 0 0 ;Wintereretal.,2 0 0 2 ;Baoetal.,1998) .Contour basedse…     

Easy cross parameterization for articulated shapes

This paper presents a novel interactive system for establishing compatible meshes for articulated shapes. Given two mesh surfaces, our system automatically generates both the global level component correspondence and the local level feature correspondence. Users can use some sketch-based tools to specify the correspondence in an intuitive and easy way. Then all the other vertex correspondences could be generated automatically. The cross parameterization preserves both high level and low level features of the shapes. The technique showed in the system benefits various applications in graphics including mesh inter- polation, deformation transfer, and texture transfer.     

二维视频序列转换为伪3D视频的方法

本文提出了一种二维视频到三维视频的转换方法。采用时域和空域相结合的方法,根据边缘信息．从图像序列中提取运动对象。对二维视频序列来说,其本身并不包含有视差信息,但是可以根据运动信息来估算视差。本文中采用基于三角形网格的浓密视差提取方法来估算。根据双目立体视觉原理和立体显示技术．我们将二维视频帧经过变换,得到伪三维立体视频帧,并合成视频序列。     

滤波预处理在分水岭分割算法中的应用

为了降低图像噪声对分水岭算法产生的过分割的影响,在分水岭算法之前进行滤波预处理.而滤波算法在平滑噪声的同时会丢失图像的边缘结构信息,为了保持在滤波预处理过程中图像的边缘结构信息,使用相似性度量的滤波函数,并且相似性度量从基于像素点的方法扩展到基于图像块的方法.