寒冷地区某既有办公建筑围护结构优化改造研究

既有公共建筑能耗中,围护结构节能潜力巨大。以兰州某既有办公建筑为例,采用DeST-C软件模拟围护结构不同材料厚度、窗型,得出系列负荷,通过对数据分析、比较,得出如下结论:外墙外保温适宜材料为50mm的挤塑板,最大热负荷节能率为45.66%;屋面适宜保温材料为65mm的挤塑板,最大热负荷节能率为4.25%;外窗各个朝向全部更换玻璃,推荐选用内张膜中空玻璃(双膜),最大热负荷节能率为7.36%;单独更换南向外窗材料,推荐选用真空镀膜复合中空玻璃,最大热负荷节能率为1.78%。     

注入种子CuBr激光器中的光谱控制

报道了采用注入种子方法．对ＣｕＢｒ激光器进行激光模式控制的实验结果。实现了单纵模ＣｕＢｒ激光脉冲的注入放大，获得了功率为１００ｍＷ水平的窄线宽铜激光辐射．在理论上分析了短脉冲高增益激光器中注入种子过程，讨论了在注入种子ＣｕＢｒ激光器中进行光谱控制的实验结果．     

氧化铝/莫来石复合陶瓷断裂行为研究

用X射线衍射方法测定了氧化铝/莫来石复合陶瓷的残余应力,并通过计算加以验证。在莫来石含量比较小的情况下,氧化铝/莫来石复合陶瓷基体拉应力与莫来石体积含量成线性关系。通过模型分析了氧化铝基体和莫来石颗粒的应力状态及其对裂纹扩展的影响。由莫来石颗粒引入的基体拉应力使裂纹倾向于向晶内扩展。观察了氧化铝/莫来石复合陶瓷断裂方式的转变,计算了穿晶断裂比率与基体应力的关系,进而建立了莫来石含量、基体应力、穿晶断裂比率三者的对应关系。这为复合陶瓷材料的制备和性能分析提供了可靠基础。     

Al2O3/SiC复合陶瓷的反应烧结

在空气中于1600℃对Al2O3/0.78%SiC纳米复合体进行2h的反应烧结,制得Al2O3/5%莫来石复合陶瓷,其中的莫来石分为两类,即3Al2O3·2SiC和Al5.65Si0.35O9.175。采用SEM和TEM研究Al2O3/莫来石复全陶瓷的微观结构。对Al2O3/莫来石复合陶瓷的密度和力学性能如杨氏模量、泊松比、硬度、韧性和强度进行了研究。     

面向信息检索的藏文文本索引策略研究

互联网文本数量持续爆炸式增长,用户通过互联网查找信息变得更加困难,响应时间得不到满足。针对藏文本身的语言学特点,探讨一种面向信息搜索的藏文文本索引建立策略,建立一种高效的藏文文本索引,以提高藏文信息检索速度。     

基于互质阵列的运动单站信号直接定位方法

信号直接定位方法是一种新型无源定位体制,具有适应低信噪比、无需参数关联等优势。为适应复杂电磁环境,该文提出了一种基于互质阵列的运动单站信号直接定位方法。以典型窄带信号为例,该文首先构建了互质阵列截获信号模型,然后推导了其差分共性阵对应的等效信号数学模型,最后使用空间谱技术构建了直接定位代价函数,实现了定位。经仿真分析验证,采用相同互质阵列时,该方法在分辨率和精度稍有损失的情况下可大幅提升传统直接定位方法的自由度,且与基于均匀线阵的直接定位方法相比,该方法在自由度、分辨率和定位精度等方面都具有优势。      

Cooperative optimal preview tracking control of continuous-time multi-agent systems

This paper presents the cooperative preview control method for continuous-time multi-agent systems with a time-invariant directed communication topology. First, the cooperative tracking preview control problem is transformed into the optimal regulation problem of an augmented system. Next, by applying the results of the standard optimal preview control of continuous-time linear systems, a controller of the augmented system is obtained. Furthermore, the stabilisability and detectability of the augmented system are studied under the fixed digraph and the prescribed leader. Then, we derive the controller of multi-agent systems with error integral and preview action that can guarantee the achievement of cooperative optimal preview tracking. Finally, the effectiveness of the controller is shown by numerical simulations.     

Hydrological Changes of the Irtysh River and the Possible Causes

Hydrological changes of the Irtysh River were analyzed concerning the changes of annual runoff and its distribution features within a year measured by coefficient of variation and concentration degree. Abrupt changes were detected by the heuristic segmentation method. Possible causes of the hydrological changes were investigated considering climate changes and human activities (especially the reservoir operation). The Mann-Kendall method was applied to estimate whether the temperature and precipitation was changed. The increased precipitation in winter may increase the runoff of April. The increased temperature and the decreased precipitation in the flood season may decrease the runoff. At the middle reaches, the impact of the reservoirs at the upper reaches is significant and may be the main factor leading to the abrupt decreases in annual runoff and its intra-annual variability and concentration. The increased water surface area of the reservoirs aggravates the evaporation and leads to annual runoff reduction. The reservoirs regulate runoff by storing water in the flood season and releasing water in the dry season. While at the lower reaches, the annual runoff remained steady and its intra-annual variation and concentration were reduced gradually because the impact of the reservoirs is relative small and the climatic impact may be more relevant.     

基于DM的入侵检测系统模型研究

通过研究数据挖掘技术在入侵检测系统中的应用。提出了一个基于数据挖掘的入侵检测系统的模型。     

利用EXEC功能加载并执行程序模块的实现方法

提出利用ＤＯＳ系统提供的ＥＸＥＣ功能，在一个应用程序中直接装入并执行若干个可执行程序模块的实现方法．用该方法可将大型软件系统中若干子模块集合起来，任意调用执行，使系统结构严谨、功能清晰、操作方便．文中给出了实用源程序．