两椭球体接触时应力计算式的简化与应用

对两椭球体间接触应力公式的有关参数进行了整合，简化了应力计算式，使工程设计和实验研究中类似的应力计算变得较为方便。     

关于逻辑函数化简的行为诊断的研究

本文以逻辑函数化简的行为诊断为研究背景，提出了一种适合于解题ＩＣＡＩ系统中学生行为的、符合人类思维特征的认识诊断系统模型，详细论述了逻辑函数化简过程中，学生行为认识诊断的具体实现，在准确捕捉学生行为中的错误及错误原因等重要问题上取得了意义的研究成果。     

Punctuated simplification of man-made objects

We present a simplification algorithm for manifold polygonal meshes of plane-dominant models. Models of this type are likely to appear in man-made environments. While traditional simplification algorithms focus on generality and smooth meshes, the approach presented here considers a specific class of man-made models. By detecting and classifying edge loops on the mesh and providing a guided series of binary mesh partitions, our approach generates a series of simplified models, each of which better respects the semantics of these kinds of models than conventional approaches do. A guiding principle is to eliminate simplifications that do not make sense in constructed environments. This, coupled with the concept of “punctuated simplification”, leads to an approach that is both efficient and delivers high visual quality. Comparative results are given.     

基于统计特征的二维矢量地图鲁棒水印算法

数字矢量地图的实际应用受到数据安全性的限制，数字水印技术是解决该问题的重要辅助手段．在二维矢量地图数据中嵌入水印需要充分考虑地图数据及其应用环境的特殊性．现有算法所暴露的一个共同的缺陷是水印的嵌入会破坏原始数据的形状特征．本文提出了一种基于数据统计特征的鲁棒水印算法，该算法以地图曲线特征点提取为基础，水印的嵌入能够尽量保持曲线本身的形状特征．实验表明该水印方案具有较好的隐蔽性和鲁棒性，能够抵抗地图几何变换、数据简化、插值，以及小幅度的加性噪声．     

A Robust Algorithm for Watermarking 2D Vector Maps with Low Shape-Distortions

The technique of watermarking has been introduced into 2D vector maps for many potential applications such as protecting the copyright of important GIS （geographical information system） data and tracing the data source of military maps. In most previous works, although the validity of the map data could be preserved during the embedding procedure, the shape-distortions of the map elements are usually neglected which would tend to degrade the invisibility of the watermarking schemes. A shape-preserving algorithm for watermarking 2D vector maps is presented in this paper. A 1D distance sequence extracted from the original map is adopted as the cover data instead of 2D coordinates. A watermark bit is represented by changing the distributions of the cover data. The embedding procedure induces lower shape-distortions than in former works. Experimental results indicate better invisibility of the proposed scheme, as well as its robustness to certain attacks such as map simplification, interpolation, additive noise and most geometric transforms.     

涡轮叶片密集点云数据与CAD模型配准方法

针对密集点云数据与CAD模型的配准问题,提出了一种基于简化模型曲率计算的配准方法。该方法通过计算简化模型和CAD模型各点的曲率提取出两模型上某一对应的特征面,根据特征面求出三组对应点对并计算坐标变换矩阵;把得到的变换矩阵应用于简化前的原始点云模型实现模型的预配准;最后通过奇异值分解和最近点迭代相结合的算法实现精确配准。实例表明,该方法实现了密集点云数据与CAD模型的配准,并在保证配准精度的前提下提高了配准的速度,从而验证了方法的有效性和实用性。     

浅谈电力网无功功率最优分布的新方法

对稍微复杂的电力网,采用确定电力网无功功率最优分布的简化算法,可以使无功优化的计算过程大为简化。     

Resource Allocation for Uplink CSI Sensing Report in Multi-User WLAN Sensing

Sensing in wireless local area network (WLAN) gains great interests recently. In this paper we focus on the multi-user WLAN sensing problem under the existing 802.11 standards. Multiple stations perform sensing with the access point and transmit channel state information (CSI) report simultaneously on the basis of uplink-orthogonal frequency division multiple access (OFDMA). Considering the transmission resource consumed in CSI report and the padding wastage in OFDMA based CSI report, we optimize the CSI simplification and uplink resource unit (RU) allocation jointly, aiming to balance the sensing accuracy and padding wastage performances in WLAN sensing. We propose the minimize padding maximize efficiency (MPME) algorithm to solve the problem and evaluate the performance of the proposed algorithm through extensive simulations.     

Geometric and biomechanical analysis for computer-aided design of assistive medical devices

This paper presents geometric and biomechanical analysis for designing elastic braces used to restrict the motion of injured joints. Towards the ultimate goal of the brace research, which is to design custom-made braces of the stiffness prescribed by a physician, this paper presents an analysis of the relationship between the brace geometry/dimension and its stiffness. As input, physician-prescribed brace stiffness and 3D-scanned data of the injured joint are given. The 3D joint geometry determines the tentative dimension of the brace. When the joint is bent, the brace stuck onto it is accordingly deformed through an appropriately devised deformation model. As a result of the deformation, strain energy is stored in the brace material. The strain energy is calculated using strain energy density functions. For effective calculation, mesh simplification and surface parametrization techniques are innovatively applied, which have been widely investigated in the computer graphics field. The calculated strain energy leads to the brace stiffness, and the obtained relationship between the brace dimension and stiffness can be used for designing a custom-made brace that meets the stiffness prescribed by a physician. The experiment results prove that geometric and biomechanical analysis works quite well for computer-aided design of assistive medical devices.