利用预失真条纹校正PMP系统投影仪畸变的研究

依据摄像机畸变模型提出了一种投影条纹相位畸变校正方法来简化相位-高度映射关系.该方法首先通过投两套互相垂直的相移正弦条纹,以相位值代替投影仪像素坐标,将投影仪当成摄像机看待,标定出投影仪的内参量.然后根据标定出的投影仪镜头畸变参量对理想相位施加反向的畸变,在投影时反向畸变的光栅通过镜头畸变,又成为理想的光栅,从而简化了相位-高度映射关系.实验中,虽然由于测量误差的影响,校正后的投影仪径向畸变系数还是比原来小了1个数量级.     

“巴黎地铁定价”方案在因特网QoS中的应用

文章介绍在因特网中引入“巴黎地铁定价”(PMP)方案,把网络分成价格不同的几个通道,利用价格机制来提高因特网QoS。该方案根据价格提供区分服务,避免了QoS技术给因特网带来的复杂性,是最简单的因特网QoS解决方案。     

PMP软件架构的研究

便携式多媒体播放器(Portable Multimedia Player)已成为继MP3以后消费类电子产品的一个新热点。介绍以TI的DM320为主芯片,基于嵌入式Linux的PMP软件架构。整个软件架构包括Bootloader、嵌入式Linux内核、多媒体框架、以及上层主GUI和各种应用程序。以本软件框架为背景的“便携式多媒体应用软件”课题已经成功地申请了“上海市创新基金”,目前“国家创新基金”正在对本课题进行评审。     

Theoretical Studies on the Reaction Mechanism of Hydroxyl Radical with 1,1,1-Trichloroethane

Ab initio and density functional theory calculations have been carried out to investigate the reaction of hydroxyl radical (OH) and 1,1,1-trichloroethane (CH3CCl3). The potential energy surface has been given according to the relative energies calculated at the MP2/cc-pVTZ level after the spin projection (PMP2). Five reaction channels were identified and the intramolecular hydrogen bonding was observed in some transition state structures. The barrier heights and reaction enthalpies calculated for all possible channels show that the hydrogen abstraction channel is predominant kinetically and thermodynamically. The contribution from other channels was predicted to be minor.     

IEEE 802.16和WiMax的组网技术

如何提高网络资源利用率和网络传输效率是无线通信领域面临的难题。作为宽带无线接入系统的标准，IEEE802，16在物理层采用正交频分复用技术和灵活的编码调制方式采提高传输速度和性能；在MAC层采用预约与竞争相结合的调度机制，以连接、服务流等与服务质量（QoS）相关的概念为基础。在入网与初始化、帧结构设计上优化设计，提高网络吞吐量，降低网络时延，使网络配置更加灵活。WiMAX基于IEEE802．16技术标准。采用点对多点（PMP）方式实现灵活组网，是宽带无线接入系统的典型血用技术。     

Room temperature phosphorescence in the liquid state as a tool in analytical chemistry

A wide-ranging overview of room temperature phosphorescence in the liquid state (RTPL¹) is presented, with a focus on recent developments. RTPL techniques like micelle-stabilized (MS)-RTP, cyclodextrin-induced (CD)-RTP, and heavy atom-induced (HAI)-RTP are discussed. These techniques are mainly applied in the stand-alone format, but coupling with some separation techniques appears to be feasible. Applications of direct, sensitized and quenched phosphorescence are also discussed. As regards sensitized and quenched RTP, emphasis is on the coupling with liquid chromatography (LC) and capillary electrophoresis (CE), but stand-alone applications are also reported. Further, the application of RTPL in immunoassays and in RTP optosensing—the optical sensing of analytes based on RTP—is reviewed. Next to the application of RTPL in quantitative analysis, its use for the structural probing of protein conformations and for time-resolved microscopy of labelled biomolecules is discussed. Finally, an overview is presented of the various analytical techniques which are based on the closely related phenomenon of long-lived lanthanide luminescence. The paper closes with a short evaluation of the state-of-the-art in RTP and a discussion on future perspectives.