发音过程中舌头运动的3D可视化方法*

研究中文发音过程中舌头运动的3D可视化问题。根据核磁共振数据构建舌头精细的3D模型,在此基础上,提取舌背表面处3个点的EMA数据为驱动源,利用弹簧网技术真实再现中文发音过程中的舌头运动。为了验证文中建模和舌头运动合成方法的有效性,使用计算机图形学的方法模拟舌头运动的细节效果,并对比其与由语言学家亲自拍摄的“普通话发音器官动作特征”的X光影像。实验表明,文中方法实现的3D舌头运动符合真实的舌头运动情况,拥有广泛的应用前景。     

Embedding Pyramids into 3D Meshes

The pyramid architecture is a powerful topology in the area of computer vision. On the other hand, the 3D mesh architecture possesses rich topological features which make it suitable for building scalable parallel processor systems. The usefulness of these two architectures has led us to consider the problem of embedding pyramids into 3D meshes, for which we present two solutions. The first solution, termednatural embedding,maps a pyramid into a 3D mesh such that each level of the pyramid is mapped to a single level of the 3D mesh. The second solution, termedmultiple embedding,allows simultaneous embedding of multiple pyramids into a single 3D mesh. The quality of both solutions is evaluated using dilation and expansion measures. Using the multiple embedding, we are able to obtain an average dilation of 1.26 and a near-optimal expansion of 1.12.     

关于Autostereoscopic 3D技术的几点探讨

从计算机图形学的观点对立体与三维的关系、立体成像原理以及影响立体显示的因素等问题作了探讨，分析总结了基于OpenGL/GLSL的立体显示编程方法，介绍了Autostereoscopic 3D技术的最新进展。     

Taking a 2D educational title into 3D

Maturing software for creating real-time interactive 3D (3D/VR) and hardware enabling its delivery give us the chance to explore practical issues involved in making commercially viable 3D/VR content. In October 1996, The Learning Company released the educational title Logic Quest, built using Sense8's WorldToolKit software. One of the first commercial 3D/VR children's titles for Windows 95, Logic Quest provides an example of what is involved in converting a 2D title (Think Quick!) to 3D. Studying the process the company followed lets us evaluate some of the challenges and benefits of moving a 2D title to 3D     

基于三维加速度信息的上肢动作质量评价的研究

利用主成份分析对基于加速度信息的上肢动作质量进行评价,并利用评价结果驱动人机交互游戏中球的线路、旋转或者球速.研究结果表明在本套系统内影响上肢动作质量主要有爆发力和耐力两个因素.     

A procedural method to exchange editable 3D data from a free-hand 2D sketch modeling system into 3D mechanical CAD systems

In the concept development phase, a designer wants to rapidly create a product’s overall shape and user interfaces by making simple sketches, known as ‘thumbnail sketches’, to evaluate ideas and possibilities. Free-hand 2D sketch systems are regarded as a computerized tool for making thumbnail sketches. After the concept development phase, subsequent editing of the 3D data reconstructed from a free-hand 2D sketch with a 3D mechanical CAD system in the detail design phase is indispensable because inaccurate dimensions are inherent in a free-hand 2D sketch. For this reason, we present a new method to translate 3D data reconstructed from a free-hand 2D sketch into an editable form that reflects design intent so that the translated data can be directly used in 3D mechanical CAD systems. The feasibility of the proposed method has been demonstrated through experiments with prototype systems.     

Incorporating non-motion cues into 3D motion segmentation

We address the problem of segmenting an image sequence into rigidly moving 3D objects. An elegant solution to this problem in the case of orthographic projection is the multibody factorization approach in which the measurement matrix is factored into lower rank matrices. Despite progress in factorization algorithms, their performance is still far from satisfactory and in scenes with missing data and noise, most existing algorithms fail.In this paper we propose a method for incorporating 2D non-motion cues (such as spatial coherence) into multibody factorization. We show the similarity of the problem to constrained factor analysis and use the EM algorithm to find the segmentation. We show that adding these cues improves performance in real and synthetic sequences.     

Diving into the depths of immersive 3D

Commercial use of three-dimensional imaging is discussed. Applications include surgical simulation in medical education, simulation of stealthy torpedos, astronaut training, and data visualization.     

二维概念格图形的三维重构研究

介绍了二维概念格图形向三维空间转化和延伸的必要性和现状。通过对传统概念格图形分层定位布局方法的研究与分析,提出并实现了一种新的以具有大量的平行四边形和有向线段为基本特征的概念格在三维空间的自动布局算法,描述了一种基于该算法的二维概念格图形的三维重构机制,有效地解决了节点横向过度扩张的问题并减少了线段交叉,较好地实现了复杂概念格图形的三维可视化,为知识发现和知识处理提供了良好的基础。     

二维概念格图形的三维重构研究

介绍了二维概念格图形向三维空问转化和延伸的必要性和现状.通过对传统概念格图形分层定位布局方法的研究与分析,提出并实现了一种新的以具有大量的平行四边形和有向线段为基本特征的概念格在三维空间的自动布局算法,描述了一种基于该算法的二维概念格图形的三维重构机制,有效地解决了节点横向过度扩张的问题并减少了线段交叉,较好地实现了复杂概念格图形的三维可视化,为知识发现和知识处理提供了良好的基础.     

3D SLAM from stereoimages

A method of visual navigation by stereoimages for autonomous underwater vehicles is suggested. Two modifications of the method are considered. The first one is based on integration of measurement data of onboard navigation system with visual data. The second modification relies on the use of a six-cloud computation scheme. Results of computational experiments with model data are presented.     

Dynamic integration of height maps into a 3D world representation from range image sequences

Integration of 21/2D sketches obtained at different observation stations into a consistent world (or object) representation is one of the central issues in computer vision and robotics. The resolution and accuracy of 21/2D sketches may be different from one view point to another, and inconsistent data between different observations may occur. This article presents an approach to building a spatiotemporal representation of dynamic scenes including moving objects from a sequence of range images taken by a moving observer. A range image is transformed into a height-map representation, which is segmented into the ground plane and objects on it. In order to capture the resolution and accuracy of the range information and the consistency of the height information between different height maps, we define a reliability measure of the height information for each bucket on the height map. Using this reliability, the system finds the correspondences of both static and moving objects between different observations, and successively refines the height information and its reliability with newly acquired data, dealing with inconsistent data. Final representation of the integrated height map consists of the time stamp of the last observation, region labels of static and moving objects and their spatiotemporal properties such as height information, its reliability, and the velocities of both the observer and independently moving objects. We applied the method to road scenes physically simulated by landscape toy models and show the experimental results.     

Building a Large Database of Facial Movements for Deformation Model‐Based 3D Face Tracking

We introduce a new markerless 3D face tracking approach for 2D videos captured by a single consumer grade camera. Our approach takes detected 2D facial features as input and matches them with projections of 3D features of a deformable model to determine its pose and shape. To make the tracking and reconstruction more robust we add a smoothness prior for pose and deformation changes of the faces. Our major contribution lies in the formulation of the deformation prior which we derive from a large database of facial animations showing different (dynamic) facial expressions of a fairly large number of subjects. We split these animation sequences into snippets of fixed length which we use to predict the facial motion based on previous frames. In order to keep the deformation model compact and independent from the individual physiognomy, we represent it by deformation gradients (instead of vertex positions) and apply a principal component analysis in deformation gradient space to extract the major modes of facial deformation. Since the facial deformation is optimized during tracking, it is particularly easy to apply them to other physiognomies and thereby re‐target the facial expressions. We demonstrate the effectiveness of our technique on a number of examples.     

Optimizing 3D Irregular Object Packing from 3D Scans Using Metaheuristics

For efficient construction-assemblies transportation, volume constrained 3D printing, dry stacking, and facility waste management, a common problem must be solved. It is the practical problem of packing irregular 3D rigid objects into a container with fixed dimensions so that the volume of the final packed objects is minimized. To solve this problem, a methodology is presented that begins with capturing the initial as-is 3D shape data for each object, followed by a metaheuristic-based packing optimization algorithm. This methodology is demonstrated to be effective in two situations with known optimum solutions and in a third situation involving packing of real-life as-is objects. A high-level selection algorithm that is designed to guide the search of possible object subsets, when not all objects can fit into a single predefined container, is discussed as well. Performance is examined for variations, and a preliminary sensitivity analysis is performed. The methodology and its key algorithms are demonstrated to produce effective packing solutions in a mostly automatic manner. Object packing for this class of applications in civil engineering can thus be potentially improved in terms of outcome efficiency and level of planning effort required.     

Integration of 3D dynamic models being created by 3D machine vision system into telerobotics applications

State of the art and outlook of machine vision systems for telerobotics are overviewed. A project of integration of compression and streaming functions for threedimensional dynamic model data being obtained from a three-dimensional machine vision system into a distributed robotic system is discussed.     

Extending distortion viewing from 2D to 3D

Addresses the visual exploration of 3D information layouts. Several visual exploration techniques have been proposed for 2D information layouts. Many of these try to take advantage of humans' natural visual pattern-recognition abilities to understand global relationships while simultaneously integrating this knowledge with local details. This desire for detail-in-context views (also called fisheye, multiscale and distortion views) has fueled considerable research in the development of distortion viewing tools. Generally, these tools provide space for magnification of local detail by compressing the rest of the image. In considering a possible detail-in-context view for 3D layouts, we first examine 2D distortion techniques, bearing in mind the particular 3D problem of occlusion. Comparing 2D and 3D information layout adjustment tools leads directly to a 3D visual access tool that clears a line of sight to any region of interest. While our technique can extend to any type of 3D information display, we focus on graphs