Variational mesh segmentation via quadric surface fitting

We present a new variational method for mesh segmentation by fitting quadric surfaces. Each component of the resulting segmentation is represented by a general quadric surface (including plane as a special case). A novel energy function is defined to evaluate the quality of the segmentation, which combines both $L^2$ and $L^{2,1}$ metrics from a triangle to a quadric surface. The Lloyd iteration is used to minimize the energy function, which repeatedly interleaves between mesh partition and quadric surface fitting. We also integrate feature-based and simplification-based techniques in the segmentation framework, which greatly improve the performance. The advantages of our algorithm are demonstrated by comparing with the state-of-the-art methods.     

面向框架的管理信息系统架构

随着企业信息化建设的推进,诸多管理信息系统的独立开发模式和不合理的框架设计耗费了大量的时间和人力．研究和设计了面向框架的管理信息系统架构,通过业务需求抽象和功能构件标准化,缩短开发周期,节省开发成本,提高软件质量,其可扩性和灵活性解决了相对固化的软件开发模式与企业快速变化的运营环境之间的矛盾．该研究方案对管理及其他应用系统的研发均有很好的借鉴作用．     

基于关联挖掘的软件错误定位方法

基于覆盖率的错误定位(Coverage Based Fault Localization,CBFL)方法旨在通过分析程序执行的结果预测错误信息,是一种行之有效的错误定位方法.然而,CBFL方法中代码覆盖率的独立统计忽略了程序内存在的复杂控制依赖和数据依赖,从而忽视了语句间的语义关系,影响错误定位的准确性.该文借助实例重点分析了基于代码覆盖率所得到的错误可疑度与错误代码的表现关系,指出现有CBFL方法的不足是片面地将基于覆盖率的错误可疑度直接作为错误代码判定的依据;提出程序失效规则及基于覆盖向量的覆盖信息分析模型,并在此模型基础之上,指出高可疑代码与错误代码在执行路径上的覆盖一致性,进而提出用以挖掘与高可疑代码相关联的错误代码的频繁集求解方法.以SIR基准程序为实验对象建立的受控实验结果表明,相比之前的研究,文中方法在一定程度上能够改进错误定位结果.     

高斯二阶差分特征算子在图像拼接中的应用

为了将同一场景中具有重叠区域序列的图像快速准确合成一幅具有宽视角、高分辨率的图像,提出了基于高斯二阶差分(D2oG)特征检测算子的SIFT算法.采用高斯二阶差分(D2oG)金字塔的过零点检测提取图像尺度不变特征点,并选用RANSAC算法对特征点匹配对进行提纯,在此基础上计算不变换矩阵H,最后,用渐进渐出平滑算法完成图像的无缝拼接.实验中分别采用所提方法和SIFT算法对具有典型变换的4种图像进行拼接与测试,结果表明:所提方法提取的匹配点数、拼接所消耗时间明显低于采用SIFT算法,同时匹配效率也高于后者.此方法降低了运算复杂度的同时,图像拼接实时性也得到提高.     

High-quality 2D mesh generation without obtuse and small angles

In this paper, we present an efficient method to eliminate the obtuse triangles for high quality 2D mesh generation. Given an initialization (e.g., from Centroidal Voronoi Tessellation—CVT), a limited number of point insertions and removals are performed to eliminate obtuse or small angle triangles. A mesh smoothing and optimization step is then applied. These steps are repeated till a desired good quality mesh is reached. We tested our algorithm on various 2D polygonal domains and verified that our algorithm always converges after inserting a few number of new points, and generates high quality triangulation with no obtuse triangles.     

Surface micromachined high-performance RF MEMS inductors

High-performance three-dimensional (3-D) microinductors with air-core and polyimide-core were fabricated by using simple MEMS technology. Both inductors have electroplated copper coils to minimize resistance to obtain high quality factor. The measurement results show that both inductors have high Q-factors over wide range of operating frequency. The maximum Q-factor of the polyimide-core is 36.5 and the inductance is 1.42 nH at 4.5 GHz, while the maximum Q-factor of the air-core inductor is 22.9 and the inductance is 1.17 nH at 5.5 GHz. The series resistance/parasitic capacitance of the polyimide-core inductor and air-core inductor is 1.05 Ω/1.07 pF and 1.82 Ω/0.57 pF respectively at the peak-Q frequency.     

Design, fabrication and performance of a new vibration-based electromagnetic micro power generator

This paper presents a new vibration-based electromagnetic micro power generator fabricated using microelectromechanical systems (MEMS) technology, which can convert ambient vibration energy into electric power. The microgenerator consists of a permanent magnet of NdFeB, a copper planar spring and a two-layer copper coil. ANSYS modal analysis was used to predict the resonant frequencies and resonant vibration modes of the spring-mass system. The detailed fabrication processes of the microgenerator are given. Experimental results show that the prototype microgenerator can generate open-circuit voltage of 60 mV ac peak–peak with 121.25 Hz input frequency and the acceleration of 1.5g (g=9.8 m/s²). The experimental and simulated results were compared and discussed.     

互联网通信中的两个数学模型及求解

面对内外众多客户对Ｗｅｂ服务信息的频繁访问请求,容易形成访问瓶颈,须有效合理地组织、分配和规划内部网信息资源,以达到减轻服务器的负担;为避免对同一信息过多的重复的访问,引起通信费用不必要的浪费和信道负担的增加,因此必须设法降低访问费用,提高Ｉｎｔｒａｎｅｔ网使用效率。本文通过引入集合划分问题（ＳＰＰ）和背包问题（ＫＮＡＰＳＡＣＫ）数学模型及相应算法,定量地解决了“访问瓶颈”和“通信费用”两个关于互     

创制杀菌剂啶菌恶唑的生物活性及应用研究(Ⅱ)黄瓜灰霉病

啶菌恶唑是一种结构新颖、作用方式独特的新型杀菌剂,具有保护、治疗效果及良好的内吸传导性。对子囊菌、担子菌和半知菌引起的多种植物病害具有良好的防治作用。啶菌恶唑对黄瓜灰霉病具有很高的杀菌活性,室内离体试验结果啶菌恶唑对黄瓜灰霉病(Botrytis cinerea Pers)的EC50值为0．199μg／ml;1998～2002年多点的田间小区试验结果表明：啶菌恶唑对黄瓜灰霉病具有良好的防治效果,在200～400g a．i．／hm^2处理剂量下、施药2～3次、间隔期6～8d可有效控制黄瓜灰霉病的发生与危害。防效优于目前生产上推广使用的多菌灵、腐霉利,菌核净、嘧霉胺等常规杀菌剂。     

Distinguishing Computer-Generated Images from Natural Images Using Channel and Pixel Correlation

Journal of Computer Science and Technology - With the recent tremendous advances of computer graphics rendering and image editing technologies, computergenerated fake images, which in general do...