用于光纤光栅传感解调系统的线阵InGaAs驱动时序电路的设计

从理论上分析了线阵InGaAs光电探测器阵列在采用光谱成像技术的光纤光栅传感解调系统中的的成像原理,在此基础上,对日本滨淞光子公司生产的G9212 型号的线阵InGaAs结构、工作方式等光电信号处理过程进行讨论.针对该型号的光电探测器阵列设计了使其正常工作的驱动时序电路,并用Verilog HDL 语言进行模块描述和CPLD实现驱动时序电路的仿真.实验结果表明,设计符合光纤光栅传感解调系统中线阵InGaAs实际工作需要.     

FTF加弹机绊丝与成形不良的控制

介绍了ＦＴＦ加弹机的特性,通过对工艺、设备及辅料的有效控制,大大减少了绊丝和成形不良现象,为进一步稳定生产、提高产品质量总结出最佳工艺参数。     

超声波及其在粮食食品工业中的应用

介绍了超声波特性及超声波的发生方法,并列举了其在粮食食品工业中的应用实例。     

进口板式换热器在亚法糖厂的使用

本文着重介绍了进口板式换热器在云南亚法糖厂的使用情况,并从节能角度出发,通过分析,提出了更有效发挥板式换热器节能效果的方法。     

CDF填充树脂在全粒面牛皮上的应用研究

本文研究了CDF树脂填充全粒面牛皮时渗透剂用量、填充液配比、填充深度等对填充效果的影响,确定了该树脂在全粒面牛皮上使用时相应的应用工艺。     

Medium access control in ultra-wideband wireless networks

Ultra-wideband (UWB) transmission is an emerging wireless communication technology with unique potential merits such as high-rate, low-transmission power, immunity to multipath propagation, and capability in precise positioning. It has received significant interests for future wireless communications from both academia and industry. In UWB wireless networks, medium access control (MAC) is essential to coordinate the channel access among competing devices. The unique UWB characteristics not only pose significant challenges but also offer great opportunities in efficient UWB MAC design. This paper presents a comprehensive overview of UWB MAC development on four important aspects: multiple access, overhead reduction, resource allocation, and quality of service (QoS) provisioning, and identifies some future research issues.     

基于图像的激光微尺度烧蚀质量估算方法

激光微尺度烧蚀下的烧蚀质量是激光微推进系统中评估比冲等性能参数的重要物理量,文中在利用扫描电镜得到的烧蚀坑图像的基础上,基于灰度表面重构形貌方法,建立了微尺度烧蚀坑形貌三维模型重构算法;针对图像噪声影响,对图像进行分段平滑,有效地解决了量化误差和灰度模糊对重构形貌的影响,实现了烧蚀坑体积估算.结果 表明:所提出的方法能够快速有效地重构激光微尺度烧蚀下烧蚀坑形貌的三维形状,进而计算其烧蚀质量.     

Robust l 2–l ∞ Filter for Uncertain Discrete-Time Switched Time-Delay Systems

This paper is concerned with the problem of robust l ₂–l _∞ filter design for a class of uncertain switched time-delay systems based on a switched Lyapunov functional. The parametric uncertainties are assumed to be time varying but norm bounded. The purpose is to design a switched filter such that, for all admissible uncertainties, the resulting filtering error system is robustly stable and satisfies a prescribed l ₂–l _∞ performance level. By introducing some extra matrices, a desired filter can be constructed by solving certain linear matrix inequalities (LMIs). A numerical example is given to demonstrate the effectiveness of the proposed method.     

Resource Management and QoS Provisioning for IPTV over mmWave-based WPANs with Directional Antenna

There is an increasing interest in 60 GHz millimeter-wave (mmWave) communication technologies for multi-Gigabit wireless personal area networks (WPAN), aiming to support broadband multimedia applications. Internet Protocol TV (IPTV) is an emerging killer application which requires high data rate and stringent quality of services (QoS) in terms of delay and packet loss. In this paper, we propose a method to efficiently support high definition video flows in a mmWave-based WPAN with QoS guarantee, considering the characteristics of both the IPTV traffic and the mmWave communication technology. We first quantify the effective bandwidth of IPTV video sources using a simple, two-level Markov traffic model. Considering the overheads of the protocol stack in mmWave WPANs, we then quantify the minimum channel time needed for each IPTV flow. Since mmWave-based WPANs will deploy directional antennas to not only extend the transmission range, but also reduce the interference level to neighboring flows, we further propose an admission control scheme and scheduling algorithm to improve the network resource utilization by taking advantage of concurrent transmissions. Extensive simulations with NS-2 using real video traces have validated our analysis and demonstrated the efficiency and effectiveness of the proposed schemes, which will be an enabling technology for future mmWave-based WPANs supporting IPTV services. Part of this work was presented at 2008 Int. Conf. Heterogeneous Networking for Quality, Reliability, Security and Robustness (QShine’08), Hong Kong, July 2008. This work has been supported by research grants from the Natural Sciences and Engineering Research Council (NSERC) of Canada.