中国多媒体通信业务市场展望

多媒体通信发展如火如荼，对未来业务市场的正确估计将对网络的发展和建设具有重要的指导意义。本文提出ＩＰ网络、ＩＰ技术和宽带技术，社会发展影响是多媒体通信业务市场的构成因素，并在此基础上，通过列举详尽的数据，从业务终端，计算机普及率和上网率以及计算机的应用状况（包括商用和家用）等方面，对我国２０００年乃至２０１０年的多媒体通信业务市场进行了展望。     

Characterisation and modelling of a 5 kW PEMFC for transportation applications

In the framework of the French inter lab SPACT project (fuel cell systems for transportation applications), a 10 kW PEM fuel cell testing bench has been installed in 2002 in the national fuel cell test platform located in Belfort, France. The behaviour of a 5 kW fuel cell, fed with humidified pure hydrogen gas and compressed air, has been investigated by the Laboratory of Electrical Engineering and Systems (L2ES) in association with the French National Institute for Transport and Safety Research (INRETS).     

Combined Optical and MR Bioimaging Using Rare Earth Ion Doped NaYF4 Nanocrystals

Here, novel nanoprobes for combined optical and magnetic resonance (MR) bioimaging are reported. Fluoride (NaYF₄) nanocrystals (20–30 nm size) co‐doped with the rare earth ions Gd³⁺ and Er³⁺/Yb³⁺/Eu³⁺ are synthesized and dispersed in water. An efficient up‐ and downconverted photoluminescence from the rare‐earth ions (Er³⁺ and Yb³⁺ or Eu³⁺) doped into fluoride nanomatrix allows optical imaging modality for the nanoprobes. Upconversion nanophosphors (UCNPs) show nearly quadratic dependence of the photoluminescence intensity on the excitation light power, confirming a two‐photon induced process and allowing two‐photon imaging with UCNPs with low power continuous wave laser diodes due to the sequential nature of the two‐photon process. Furthermore, both UCNPs and downconversion nanophosphors (DCNPs) are modified with biorecognition biomolecules such as anti‐claudin‐4 and anti‐mesothelin, and show in vitro targeted delivery to cancer cells using confocal microscopy. The possibility of using nanoprobes for optical imaging in vivo is also demonstrated. It is also shown that Gd³⁺ co‐doped within the nanophosphors imparts strong T1 (Spin‐lattice relaxation time) and T2 (spin‐spin relaxation time) for high contrast MR imaging. Thus, nanoprobes based on fluoride nanophosphors doped with rare earth ions are shown to provide the dual modality of optical and magnetic resonance imaging.     

紧凑型FLC光纤PDL模块

描述了紧凑型FLC（铁电液晶）光纤PDL（光子延迟线）模块的结构和运转特性；分析了插入损失；提出多信道运转时依赖于波长的设计方案。     

An Effective Software Pipelining Algorithm for Clustered Embedded VLIW Processors

This paper proposes a software pipelining framework, CALiBeR (ClusterAware Load Balancing Retiming Algorithm), suitable for compilers targetingclustered embedded VLIW processors. CALiBeR can be used by embedded systemdesigners to explore different code optimization alternatives, that is, high-qualitycustomized retiming solutions for desired throughput and program memory sizerequirements, while minimizing register pressure. An extensive set of experimentalresults is presented, demonstrating that our algorithm compares favorablywith one of the best state-of-the-art algorithms, achieving up to 50% improvementin performance and up to 47% improvement in register requirements. In orderto empirically assess the effectiveness of clustering for high ILP applications,additional experiments are presented contrasting the performance achievedby software pipelined kernels executing on clustered and on centralized machines.     

电真空器件用氧化铝陶瓷的介电性能

对影响氧化铝陶瓷介电性能(介电常数、介电损耗和介电强度)的各种因素进行了较为系统的评述,并对相应的影响机理进行了分析和探讨.希望能为电真空用氧化铝陶瓷的质量控制和检验提供理论依据,同时也为工艺方法(包括材料工艺和电真空器件工艺)的选择提供有益的技术参考.     

Improving Reconfigurable Systems Reliability by Combining Periodical Test and Redundancy Techniques: A Case Study

This paper revises and introduces to the field of reconfigurable computer systems, some traditional techniques used in the fields of fault-tolerance and testing of digital circuits. The target area is that of on-board spacecraft electronics, as this class of application is a good candidate for the use of reconfigurable computing technology. Fault tolerant strategies are used in order for the system to adapt itself to the severe conditions found in space. In addition, the paper describes some problems and possible solutions for the use of reconfigurable components, based on programmable logic, in space applications.     

FPGA-based Physical Unclonable Functions: A comprehensive overview of theory and architectures

Physically Unclonable Functions (PUFs) are a promising technology and have been proposed as central building blocks in many cryptographic protocols and security architectures. Among other uses, PUFs enable chip identifier/authentication, secret key generation/storage, seed for a random number generator and Intellectual Property (IP) protection. Field Programmable Gate Arrays (FPGAs) are re-configurable hardware systems which have emerged as an interesting trade-off between the versatility of standard microprocessors and the efficiency of Application Specific Integrated Circuits (ASICs). In FPGA devices, PUFs may be instantiated directly from FPGA fabric components in order to exploit the propagation delay differences of signals caused by manufacturing process variations. PUF technology can protect the individual FPGA IP cores with less overhead. In this article, we first provide an extensive survey on the current state-of-the-art of FPGA based PUFs. Then, we provide a detailed performance evaluation result for several FPGA based PUF designs and their comparisons. Subsequently, we briefly report on some of the known attacks on FPGA based PUFs and the corresponding countermeasures. Finally, we conclude with a brief overview of the FPGA based PUF application scenarios and future research directions.     

Improving evidence-based assessment of players using serious games

Serious games are highly interactive systems which can therefore capture large amounts of player interaction data. This data can be analyzed to provide a deep insight into the effect of the game on its players. However, traditional techniques to assess players of serious games make little use of interaction data, relying instead on costly external questionnaires. We propose an evidence-based process to improve the assessment of players by using their interaction data. The process first combines player interaction data and traditional questionnaires to derive and refine game learning analytics variables, which can then be used to predict the effects of the game on its players. Once the game is validated, and suitable prediction models have been built, the prediction models can be used in large-scale deployments to assess players solely based on their interactions, without the need for external questionnaires. We briefly describe two case studies where this combination of traditional questionnaires and data mining techniques has been successfully applied. The evidence-based assessment process proposed radically simplifies the deployment and application of serious games in real class settings.     

Theranostic USPIO‐Loaded Microbubbles for Mediating and Monitoring Blood‐Brain Barrier Permeation

Efficient and safe drug delivery across the blood‐brain barrier (BBB) remains one of the major challenges of biomedical and (nano‐) pharmaceutical research. Here, it is demonstrated that poly(butyl cyanoacrylate)‐based microbubbles (MB), carrying ultrasmall superparamagnetic iron oxide (USPIO) nanoparticles within their shell, can be used to mediate and monitor BBB permeation. Upon exposure to transcranial ultrasound pulses, USPIO‐MB are destroyed, resulting in acoustic forces inducing vessel permeability. At the same time, USPIO are released from the MB shell, they extravasate across the permeabilized BBB and they accumulate in extravascular brain tissue, thereby providing non‐invasive R ₂*‐based magnetic resonance imaging information on the extent of BBB opening. Quantitative changes in R ₂* relaxometry are in good agreement with 2D and 3D microscopy results on the extravascular deposition of the macromolecular model drug fluorescein isothiocyanate (FITC)‐dextran into the brain. Such theranostic materials and methods are considered to be useful for mediating and monitoring drug delivery across the BBB and for enabling safe and efficient treatment of CNS disorders.