基于Windows200x的WDM体系的IP过滤实现技术

基于内容的IP包过滤技术涉及到操作系统的内核态技术.通过对比用户态及内核态的特征,分析了Windows内核态的网络编程接口,采用了WDM的驱动程序模式体系及NDIS的层次架构.遵循IRP(I/O request packet)规范,实现了具有Miniport和Protocol层的中间驱动程序,并透明钩挂,截取、分析IP包.具体给出了Windows 200X系统中实现IP包过滤的鳊程技术方案.     

集成式计算机协同工作(CSCW)支持环境的研究与实现

提出了一种构造集成式计算机支持的协同工作（ＣＳＣＷ）支持环境的解决方案,介绍了集成机制的原理、消息机制与挂接机制的结合和应用,以及ＣＳＣＷ支持环境的设计与实现技术．讨论了相关问题,提出并实现了改进方案．同时,也介绍了集成式ＣＳＣＷ支持环境与视频会议系统的结合．     

基于Detours的文件操作监控方案

研究了两种文件操作监控常用的API钩挂技术,通过实验指出IAT Hook技术的不稳定性,提出使用基于Inline Hook技术的Detours来解决explorer.exe错误。最后给出了文件操作监控方案的实现方法,并对Detours技术进行了详细阐述。经测实验证,该方案确实能有效实现文件的安全保护。     

幂强化吊钩在含炸药部件跌落试验中的应用

针对含炸药部件跌落试验的特点,以幂强化材料为例分析了吊钩在跌落试验中抵抗意外跌落的能力。并结合实际应用情况,通过数值模拟简要分析理想塑性和幂强化2种材料本构模型对吊钩钩柄转角的影响关系,说明吊钩材料的制造工艺研究可以提高吊钩的抗冲击性能。     

直列泵柴油机燃用二甲醚(DME)的燃烧排放特性分析

在一台增压直列泵柴油机进行了燃用柴油和二甲醚的试验,实测了缸内压力,并据此计算了燃烧放热率,对动力性及排放特性进行了对比分析。结果表明:发动机燃用二甲醚后,功率和扭矩都有所提升,选用9°CA和12°CA供油提前角时,在不同转速下的NOx排放均低于柴油;在全负荷情况下的最高燃烧压力和峰值放热率均低于柴油;二甲醚的喷油量是柴油的两倍,但二甲醚的燃烧速度高于柴油,所以二者的燃烧持续期相差不大;选用6孔的喷嘴比5孔喷嘴燃烧更加充分,但是较高的最高燃烧压力和燃烧放热律也使得NOx排放增加。     

天然气脱水技术探讨

天然气脱水是天然气净化过程中必不可少的环节。在对国内外脱水技术调研和查阅相关文献的基础上,总结了天然气开采后的各种脱水工艺,并对其原理、工艺特点等进行了概括分析,同时也对其在国内的应用现状进行了总结,并分析运行中存在的一些问题。通过对比发现,分子筛脱水法达到的天然气露点最低,一般用于深度脱水的环境;超音速脱水法具有结构简单,无需外部动力,免维护等优点,是天然气脱水技术发展的新趋势;内联式脱液器具有新型、紧凑、高效等特点,同时可用法兰连接在管道上进行在线预脱水,通常适用于海上平台及海底脱水系统。     

PF线C型钩载荷梁优化设计

针对高线厂PF线C形钩载荷梁存在的结构缺陷，对载荷梁上吊轴的安装结构进行了改进，使之能够防尘，并减小转动摩擦阻力，减少了PF线设备故障，降低了备件消耗和系统能耗。     

Inline electron holography and VEELS for the measurement of strain in ternary and quaternary (In,Al,Ga)N alloyed thin films and its effect on bandgap energy

We present the use of (1) dark‐field inline electron holography for measuring the structural strain, and indirectly obtaining the composition, in a wurtzite, 4‐nm‐thick InAlGaN epilayer on a AlN/GaN/AlN/GaN multinano‐layer heterosystem, and (2) valence electron energy‐loss spectroscopy to study the bandgap value of five different, also hexagonal, 20–50‐nm‐thick InAlGaN layers. The measured strain values were almost identical to the ones obtained by other techniques for similarly grown materials. We found that the biaxial strain in the III‐N alloys lowers the bandgap energy as compared to the value calculated with different known expressions and bowing parameters for unstrained layers. By contrast, calculated and experimental values agreed in the case of lattice‐matched (almost unstrained) heterostructures.     

Dynamic Changes in Reactive Oxygen Species in the Shoot Apex Contribute to Stem Cell Death in Arabidopsis thaliana

In monocarpic plants, stem cells are fated to die. However, the potential mechanism of stem cell death has remained elusive. Here, we reveal that the levels of two forms of reactive oxygen species (ROS), superoxide anion free radical (O2·−) and hydrogen peroxide (H₂O₂), show dynamic changes in the shoot apex during the plant life cycle of Arabidopsis thaliana. We found that the level of O2·− decreased and disappeared at four weeks after bolting (WAB), while H₂O₂ appeared at 3 WAB and showed a burst at 5 WAB. The timing of dynamic changes in O2·− and H₂O₂ was delayed for approximately three weeks in clv3-2, which has a longer lifespan. Moreover, exogenous application of H₂O₂ inhibited the expression of the stem cell determinant WUSCHEL (WUS) and promoted the expression of the developmentally programmed cell death (dPCD) marker gene ORESARA 1 (ORE1). These results indicate that H₂O₂ triggers an important signal inducing dPCD in stem cells. Given that O2·− plays roles in maintaining WUS expression and stem cell activity, we speculate that the dynamic shift from O2·− to H₂O₂ in the shoot apex results in stem cell death. Our findings provide novel insights for understanding ROS-mediated regulation during plant stem cell death.