理论、实践经验和实践能力

掌握了理论知识并不等于有了实战经验,更不等于有实战能力。从理论到有实战能力的飞跃,只有亲临生产线,在不断解决问题过程中实现。     

从美国有线电视产业应对竞争的策略和举措获得的启示

1前言 近年来出现了有关IP电视（网络电视）和移动电视（手机电视）属于电信增值业务,应当由电信企业主办、电信部门主管的大量论调,并已在社会上造成许多误解.由于其论据是外国情况、世界趋势就是这样,而且把这些信息网络传播视听节目的产业运营前景描绘得非常光明,笔者于是认真查考有关的外国情况,写了多篇综述（本刊2005年第2、第3、第5、第6、第8、第9、第14、第16及第22期）,其中结合国情的评述,由于国内针对这些新事物的政策法规不明朗,论据尚有欠缺.     

Effective Location Based Services with Dynamic Data Management in Mobile Environments

With the proliferation of mobile computing technologies, location based services have been identified as one of the most promising target application. We classify mobile information service domains based on feature characteristics of the information sources and different patterns of mobile information access. By carefully examining the service requirements, we identify the dynamic data management problem that must be addressed for effective location based services in mobile environments. We then devise a general architecture and cost model for servicing both location independent and location dependent data. Based on the architecture and cost model, we propose a set of dynamic data management strategies that employs judicious caching, proactive server pushing and neighborhood replication to reduce service cost and improve response time under changing user mobility and access patterns. Detail behavior analysis helps us in precisely capturing when and how to apply these strategies. Simulation results suggest that different strategies are effective for different types of data in response to different patterns of movement and information access. Shiow-yang Wu is an associate professor of the Department of Computer Science and Information Engineering at National Dong Hwa University, Hualien, Taiwan, R.O.C. He received the BS and MS degrees in computer engineering from National Chiao Tung University, Hsinchu, Taiwan, ROC, and the PhD degree in computer science from the University of Texas at Austin in 1984, 1986, and 1995, respectively. His research interests include data/knowledge bases, mobile computing, distributed processing, intelligence information systems, and electronic commerce. Kun-Ta Wu was born in Taipei, Taiwan, R.O.C., in 1976. He received the B.S. degree in computer science from Soochow University, Taipei, Taiwan, R.O.C., in 1999 and the M.S. degree in computer science and information engineering from National Dong Hwa University, Hualien, Taiwan, R.O.C., in 2001. Currently, he is an Assistant Researcher in the Domestic Division at Science and Technology Information Center, National Science Council, R.O.C., as a member of Information Gathering and Analysis Group of National Information and Communication Security Taskforce. His research interests include mobile computing, wireless network and information security.     

A power-driven multiplication instruction-set design method for ASIPs

This paper presents a novel power-driven multiplication instruction-set design method for application-specific instruction-set processors (ASIPs). Based on a dual-and-configurable-multiplier structure, our proposed method devises a multiplication instruction set for low-power ASIPs. Our method exploits the execution sequences of multiplication instructions and effective bit widths of variables to reduce power consumed by redundant multiplication bits while minimizing the multiplication execution time. Experimental results on a set of DSP programs demonstrate that our proposed method achieves significant power reduction (up to 18.53%) and execution time improvement (up to 10.43%) with 18% area overhead.     

An MPEG‐4 Compliant Interactive Multimedia Streaming Platform Using Overlay Networks

This paper presents a multimedia streaming platform for efficiently transmitting MPEG‐4 content over IP networks. The platform includes an MPEG‐4 compliant streaming server and client, supporting object‐based representation of multimedia scenes, interactivity, and advanced encoding profiles defined by the ISO standard. For scalability purposes, we employ an application‐layer multicast scheme for media transmission using overlay networks. The overlay network, governed by the central entity of the network distribution manager, is dynamically deployed according to a set of pre‐defined criteria. The overlay network supports both broadcast delivery and video‐on‐demand content. The multimedia streaming platform is standards‐compliant and utilizes widespread multimedia protocols such as MPEG‐4, real‐time transport protocol, real‐time transport control protocol, and real‐time streaming protocol. The design of the overlay network was architected with the goal of transparency to both the streaming server and the client. As a result, many commercial implementations that use industry‐standard protocols can be plugged into the architecture relatively painlessly and can enjoy the benefits of the platform.     

多带抗噪声语音识别算法研究

根据Flether等人的研究,基于感知独立性假设的子带识别方法被用于抗噪声鲁棒语音识别。本文拓展子带方法,采用基于噪声污染假定的多带框架来减少噪声影响。论文不仅从理论上分析了噪声污染假定多带框架在识别性能上的潜在优势,而且提出了多带环境下的鲁棒语音识别算法。研究表明：多带框架不仅回避了独立感知假设要求,而且与子带方法相比,多带方法能更好的减少噪声影响,提高系统识别性能。     

Injection-locked Fabry-Pe/spl acute/rot laser with electronic feedback for clock recovery from high-speed OTDM signals

We demonstrate the use of an injection-locked Fabry-Pe/spl acute/rot laser diode with electronic feedback for base-rate clock recovery in N/spl times/10 Gb/s optical time-division-multiplexing (OTDM) systems. Injection-locking enhances the resonance frequency of the laser and the electrical feedback achieves strong resonance at the base-rate frequency of the injected data streams, enabling ultrastable electrical clock signal generation at the base rate of 10 GHz. Experimental demonstrations for clock recovery at 10 GHz from 40-Gb/s OTDM data streams and 4-1 demultiplexing of the data using the extracted clock after fiber transmission is presented. The timing jitter measured in the recovered electrical clock is less than 0.25 ps.     

工作流技术及其应用研究

文章介绍了工作流技术及其发展历史,对工作流的系统模型进行了详细分析,探讨了工作流技术在企业管理信息系统中的实际应用。     

动感像素全息母版图案的设计制作研究

本文介绍了一种新颖的数码像素全息高速拍摄装置来实现全息母版的制作。提出和介绍了运用Photoshop软件一些特殊的图像处理功能设计制作动感像素全息图的方法,并结合多种防伪技术,使产生的图案具有不可仿制的图形畸变特点,并列举了设计实例。