自动播控软件在硬盘播出系统中应用

随着计算机技术的不断发展,视音频服务器开始广泛应用于电视播出系统,电视播控进入了全硬盘时代。在这一高度自动化的领域中,计算机控制技术无可比拟的优越性得到了充分的体现,而相对于硬件来说,自动播控软件同样发挥着越来越重要的作用。     

基于JSP自动生成工具的实现

随着计算机及网络技术的发展,计算机技术有了新的发展。JSP是Web开发的最先进的技术,是当前Web开发人员的最好技术。但是由于JSP对web开发人员要求高,所以许多web开发人员还不能够使用这一项技术。本文基于JSP网页自动生成工具的设计和实现,提出具体的设计思想和实现方法。     

浅析VPN技术在网络安全中的应用

现在,越来越多的公司走向集团化,计算机网络又缺乏足够的安全性,网络上传输的信息随时都受到非法存取、盗听、篡改和破坏等威胁,出于对网络安全的考虑这样就迫使用户采用不同的安全措施防范。     

A double-threshold image binarization method based on edge detector

This paper presents a new double-threshold image binarization method based on the edge and intensity information. We first find seeds near the image edges and present an edge connection method to close the image edges. Then, we use closed image edges to partition the binarized image that is generated using a high threshold, and obtain a primary binarization result by filling the partitioned high-threshold binary image with the seeds. Finally, the final binarization result is obtained by remedying the primary binarization result with the low-threshold binary image. Compared with the classical binarization methods and the similar binarization methods, our method is effective on the binarization of images with low contrast, noise and non-uniform illumination.     

Interference Shaders of Thin Films

This paper presents a systematic study of light interferences at single thin films. Based on Fresnel's law, we have derived generic expressions of reflectance and transmittance for film interference, as well as specific expressions for free thin films and films coated on transparent or opaque objects. By combining film interference and volume absorption, we have obtained the reflectances and transmittances of film‐coated thin objects such as ribbons. Illumination models for all interference cases of single thin films are presented, and they have been implemented and tested for various structures and materials.     

Global Intrinsic Symmetries of Shapes

Although considerable attention in recent years has been given to the problem of symmetry detection in general shapes, few methods have been developed that aim to detect and quantify the intrinsic symmetry of a shape rather than its extrinsic, or pose‐dependent symmetry. In this paper, we present a novel approach for efficiently computing symmetries of a shape which are invariant up to isometry preserving transformations. We show that the intrinsic symmetries of a shape are transformed into the Euclidean symmetries in the signature space defined by the eigenfunctions of the Laplace‐Beltrami operator. Based on this observation, we devise an algorithm which detects and computes the isometric mappings from the shape onto itself. We show that our approach is both computationally efficient and robust with respect to small non‐isometric deformations, even if they include topological changes.     

Analysis and reduction of data spikes in thin client computing

While various optimization techniques have been used in existing thin client systems to reduce network traffic, the screen updates triggered by many user operations will still result in long interactive latencies in many contemporary network environments. Long interactive latencies have an unfavorable effect on users’ perception of graphical interfaces and visual contents. The long latencies arise when data spikes need to be transferred over a network while the available bandwidth is limited. These data spikes are composed of a large amount of screen update data produced in a very short time. In this paper, we propose a model to analyze the packet-level redundancy in screen update streams caused by repainting of graphical objects. Using this model we analyzed the data spikes in screen update streams. Based on the analysis result we designed a hybrid cache-compression scheme. This scheme caches the screen updates in data spikes on both server and client sides, and uses the cached data as history to better compress the recurrent screen updates in possible data spikes. We empirically studied the effectiveness of our cache scheme on some screen updates generated by one of the most bandwidth-efficient thin client system, Microsoft Terminal Service. The experiment results showed that this cache scheme with a cache of 2M bytes can reduce 26.7%–42.2% data spike count and 9.9%–21.2% network traffic for the tested data, and can reduce 25.8%–38.5% noticeable long latencies for different types of applications. This scheme costs only a little additional computation time and the cache size can be negotiated between the client and server.     

Algorithm-system scalability of heterogeneous computing

Scalability is a key factor of the design of distributed systems and parallel algorithms and machines. However, conventional scalabilities are designed for homogeneous parallel processing. There is no suitable and commonly accepted definition of scalability metric for heterogeneous systems. Isospeed scalability is a well-defined metric for homogeneous computing. This study extends the isospeed scalability metric to general heterogeneous computing systems. The proposed isospeed-efficiency model is suitable for both homogeneous and heterogeneous computing. Through theoretical analyses, we derive methodologies of scalability measurement and prediction for heterogeneous systems. Experimental results have verified the analytical results and confirmed that the proposed isospeed-efficiency scalability works well in both homogeneous and heterogeneous environments.     

高速磁浮列车相对位置传感器的设计

根据直线同步电机长定子的齿槽结构特性,设计了一种新型的电感式相对位置传感器.介绍了检测线圈的结构和同步解调电路,并利用DSP的运算能力,在算法上实现磁极与长定子之间的高精度定位.最后,通过实验验证表明,该传感器工作稳定,满足牵引要求.