水力喷射径向水平井生产管的工艺评定与检验

在URRS系统施工过程中 ,生产管处于多种变化复杂的应力和变形状态下 ,若出现失稳、渗漏、刺穿和断裂等事故 ,将造成巨大经济损失。为此 ,开展了水力喷射径向水平井用生产管的焊接方法、焊接设备、焊接工艺过程和焊接接头力学性能评定方法的试验研究。通过研究和试验 ,管材基本上实现了国产化 ,与之相匹配的焊接材料、焊接工艺以及质量检测技术已基本配套和规范化 ,形成了一套稳定的、可靠性较高且能完全满足现场工况的施工体系和质量保证体系     

利用CFD获取超声流量计截面速度分布

 通过CFD技术在超声波流量计设计过程中的引入,为流量系数的获取提供了新的途径.通过对特定管道的理论计算表明,采用CFD技术获取的管道内部流型完全可以与试验数据吻合,有助于超声波流量计应用场合流量系数曲线的获取及其精度的保证.     

二过碘酸合银（Ⅲ）钾引发丙类酸甲酯在淀粉上接枝共聚合反应的研究

研究了由二过碘酸合银（Ⅲ）钾（简称Ag(Ⅲ））与可溶性淀粉组成的氧化还原体系，于碱性介质中引发淀粉的接枝共聚合反应，得到高接枝效率的接枝共聚物，测定了引发剂浓度、单体浓度、pH值和反应温度对接枝参数的影响，并探讨了引发机理。     

Theory and design of a tapered line distributed photodetector

We present the theory and design of a tapered line distributed photodetector (TLDP). In the previously demonstrated velocity-matched distributed photodetector (VMDP), high electrical bandwidth is achieved by proper termination in the input end to absorb reverse traveling waves, sacrificing one-half of the quantum efficiency. By utilizing the tapered line structure and phase matching between optical waves and microwaves in our analyzed structure, a traveling-wave photodetector is more realizable and ultrahigh bandwidth can be attained due to removal of the extra input dummy load that sacrifices one-half of the total quantum efficiency. To investigate the advantages of TLDP over VMDP, we calculate their electrical bandwidth performances by using an analytic photodistributed current model. We adopted low-temperature-grown (LTG) GaAs-based metal-semiconductor-metal (MSM) traveling-wave photodetectors as example unit active devices in the analytic bandwidth calculation for their high-speed and high-power performances. Both VMDP and TLDP in our simulation are assumed to be transferred onto glass substrates, which would achieve high microwave velocity/impedance and make radiation loss negligible. The simulated bandwidth of a properly designed LTG GaAs MSM TLDP is /spl sim/325 GHz, which is higher than the simulated bandwidth of the LTG GaAs MSM VMDP with an open-circuit input end (/spl sim/240 GHz) and is almost comparable to the simulated bandwidth of an input-terminated LTG GaAs MSM VMDP (/spl sim/330 GHz). This proposed method can be applied to the design of high-bandwidth distributed photodetectors for radio-frequency photonic systems and optoelectronic generation of high-power microwaves and millimeter waves.     

Multicast routing and bandwidth dimensioning in overlay networks

Multicast services can be provided either as a basic network service or as an application-layer service. Higher level multicast implementations often provide more sophisticated features and can provide multicast services at places where no network layer support is available. Overlay multicast networks offer an intermediate option, potentially combining the flexibility and advanced features of application layer multicast with the greater efficiency of network layer multicast. In this paper, we introduce the multicast routing problem specific to the overlay network environment and the related capacity assignment problem for overlay network planning. Our main contributions are the design of several routing algorithms that optimize the end-to-end delay and the interface bandwidth usage at the multicast service nodes within the overlay network. The interface bandwidth is typically a key resource for an overlay network provider, and needs to be carefully managed in order to maximize the number of users that can be served. Through simulations, we evaluate the performance of these algorithms under various traffic conditions and on various network topologies. The results show that our approach is cost-effective and robust under traffic variations.     

移动通信系统中有效的身份认证方案和支付协议

文中给出了一个基于公钥密码的有效的身份认证和密钥交换协议，该协议可以实现通信双方的相互认证，产生的会话密钥对通信双方是公正的，且会话密钥的产生不需要其他第三方的参与，协议的结构简单，执行效率高：在此协议基础上设计了一个适用于移动通信系统的小额支付协议。     

现场总线技术在城市污水处理与气象中的应用

文章主要讨论了LonWorks现场总线技术在城市污水处理厂和气象指数预报中的应用。采用IPC和PLC控制结构对现场的各种设备实现控制和数据的采集，通过现场总线网络传输数据到中心控制室或远程终端，实现污水处理的自动控制和气象信息的实时采集和处理。     

高质量ZnO薄膜的退火性质研究

在LP－MOCVD中，我们利用Zn(C2H5)2作Zn源，CO2作氧源，在（0002）蓝宝石衬底上成功制备出皮c轴取向高度一致的ZnO薄膜，并对其进行500℃-800℃四个不同温度的退火。利用XRD、吸收谱、光致发光谱和AFM等手段研究了退火对ZnO晶体质量和光学性质的影响。退火后，（0002）ZnO的XRD衍射峰强度显著增强，c轴晶格常数变小，同时（0002）ZnOX射红衍射峰半高宽不断减小表明晶粒逐渐增大，这与AFM观察结果较一致。由透射谱拟合得到的光学带隙退火后变小，PL谱的带边发射则加强，并出现红移，蓝带发光被有效抑制，表明ZnO薄膜的质量得到提高。     

风扇磨煤机ZGMn13冲击板的失效分析

ZGMn13冲击板的失效方式为不同角度的粒子撞击和冲刷，其表面可以分为三个典型的磨损区域：低角度撞击区、高角度撞击区和冲刷区。详细分析了该三个磨损区域的磨损机理。次表面分析的结果表明，在低负度撞击和冲刷条件下，高锰钢未能充分加工硬化，耐磨性提高有限。     

基于规则的光学邻近矫正中规则的相关处理

讨论了如何选择适当的规则,如何建立简洁实用的规则库,如何应用规则库.提出了四种主要的光学邻近矫正规则,在实验结果中列举了规则库中的部分数据.利用规则矫正后的版图光刻得到的硅片图形有了明显的改善.规则库的自动建立部分 (OPCL)是基于规则的光学邻近矫正系统的重要组成部分.