一种基于物联网技术的智能路灯监控系统设计

为实现城市照明的节能环保、成本控制以及对照明设备的精细管理和远程监控,提出了一种基于物联网技术的智能路灯监控系统设计方案,并介绍了系统实现的关键技术、系统结构和系统主要功能.方案提出GPRS通信与ZigBee通信相结合的一种新型的混合网络结构,服务器上采用GIS技术实现信息图形化,该方案可对单灯或多灯进行智能监控管理.实验表明,系统可靠性较高、功耗较低,并且实施后可延长路灯的使用寿命,降低路灯的损坏率和维护费用,并能提供防盗预警功能.该系统能节省人力物力成本,提升城市照明管理的技术水平和服务水平.     

注气井井筒结垢预测研究

在油田开发过程中,油、气、水和泥浆在地层或管道中流动,当达到一定条件时,油垢、水垢或泥垢便会产生。在实际生产过程中,油垢和泥垢通常伴随着水垢而生成,所以对水垢结垢趋势的预测研究显得至关重要。介绍了Oddo-Tomos饱和指数法的理论预测模型,以及在生产过程中利用Oddo-Tomos饱和指数法预测油田结垢趋势的方法,阐述并分析了油田结垢对油田开采的影响。研究结果可为下一步的生产作业提供理论依据。     

室内燃气报警器的安装位置优化

燃气属于易燃易爆的危险性气体,当在室内有限空间发生泄漏时,会带来相当严重的后果。针对燃气泄漏扩散的特点,利用 Gambit建立室内燃气灶喷嘴处气体泄漏扩散的物理模型,并结合 CFD 流体动力学软件FLUENT模拟了燃气连续泄漏的扩散过程。对燃气在一定温度梯度、不同湿度条件下的扩散效果进行了对比,并监测了指定安装区域内不同安装点处的浓度,以期达到优化报警器安装位置的目的。结果表明,室内空气的相对湿度和安装位置是影响报警时间的关键因素;在相同安装点,当空气相对湿度增加15%时,报警时间延迟近6 s;在一定的空气相对湿度下,报警器距离泄漏口水平位置增加1 m,报警时间滞后4 s。     

一种用于多方通信的新的SMC安全协议*

对主流安全协议在多方通信环境下的应用进行分析,总结其各自优缺点。在综合各个协议优点的基础上,提出并介绍了一个用于多方通信环境下的SMC(securing multiparty communications)协议,该协议工作在传输层之上,具有更强的可部署性。SMC协议被设计用来取代当前用于多方通信环境的MSEC协议族。通过将SMC协议与MSEC协议族进行比较,证明SMC协议具有与MSEC协议族一致的安全性,并且具有更强的可部署性。     

基于纹理切换的虚拟战斗人员三维显示方法

为了解决形象化模型显示方法硬件依赖性过高、不易实现推广等问题,从“分队指挥模拟对抗演练系统”虚拟战斗人员显示的实际需要出发,提出了一种基于纹理切换的虚拟战斗人员三维显示方法. 重点叙述了这种纹理切换显示方法的基本思路、算法思想、技术路线以及具体实现;并且对实现过程中涉及到的在视点角度发生变化的条件下,如何同时保持纹理框架朝向不变以及如何保持虚拟战斗人员逻辑方向不变两个纹理切换的关键问题进行了重点研究.     

雅安市旅游WebGIS的构建及其存在问题探讨*

基于ArcIMS9.0系统,并结合ArcXML、JavaScript等编程技术、数据库技术及空间数据库引擎ArcSDE,构建了雅安市旅游WebGIS系统。在WebGIS基础平台上,对雅安市旅游资源信息进行采集、存储、管理、分析和图形处理显示,并由图形、图像、文字和声音等多种形式综合展示。针对系统构建过程中遇到的一些主要问题提出了有效的解决方案。针对目前尚未有适合中国国情的地址编码方案问题,率先编制了中国式的地址标准化规则文件和匹配规则文件;利用MapObjects＋VB 6.0开发了地址匹配软件,不仅提高了地址匹配成功率,还大幅度提升了匹配效率;利用TM和DEM等多源信息融合技术解决了三维＂近自然＂地形的显示问题。     

凝胶法制备Cu-BTC块体及其吸附脱除二甲基二硫醚性能

金属有机骨架材料Cu-BTC具有高孔隙率、易调控的骨架结构以及含过渡金属等特点,是吸附脱除硫化物的优异材料。采用凝胶法在常温条件下制备块状样品Cu-BTC-g,并通过X射线衍射(XRD)、扫描电子显微镜(SEM)、红外光谱(FT-IR)、拉曼光谱(Raman)、X射线光电子能谱(XPS)、N₂吸附-脱附等手段对其进行分析表征,同时测定Cu-BTC-g样品对模型硫化物二甲基二硫醚(DMDS)的静态吸附容量、吸附热力学和动力学特性。结果表明：凝胶法制备的Cu-BTC-g样品晶体平均尺寸约为0.2μm、比表面积为901 m²/g、孔体积为0.40 cm³/g,晶体尺寸、比表面积和孔体积均小于溶剂热法合成的样品Cu-BTC-s;在吸附温度298 K下,Cu-BTC-g样品的DMDS吸附容量为110.8 mg/g,比Cu-BTC-s样品提高12%。     

Kinetics simulation of propylene epoxidation over different Ti species in TS-1

A thorough experimental investigation on the kinetic behavior of liquid-phase propylene epoxidation over TS-1 and tetrapropylammonium hydroxide (TPAOH) treated TS-1 catalysts was conducted in a fixed-bed reactor. The amounts of different coordinated Ti species in the catalysts were quantified by spectroscopies, and their catalytic performances of the epoxidation and alcoholysis of propylene oxide were measured by kinetic modeling. The study shows that the TPAOH treatment converted some of the tetrahedrally coordinated Ti to octahedrally coordinated Ti, and both species were active for the epoxidation and alcoholysis. The superior catalytic performance observed over the TPAOH treated TS-1 is due to two factors, the increased percentage of active sites, and reduced energy barrier for epoxidation on the octahedrally coordinated Ti. In addition, as the H₂O₂ conversion increases, the adsorption equilibrium constant of propylene oxide plays a more decisive role than the activation energy for the selectivity of propylene glycol monomethyl ethers.     

Electric field assisted solid-state interfacial joining of TaC-HfC ceramics without filler

The application of ultra-high-temperature ceramics (UHTCs) demands effective ways of joining in overcoming the problems associated with the fabrication of complex-shaped components. In this study, we choose to investigate a new method of rapidly joining pre-sintered TaC and HfC ceramics without any filler material using the spark plasma sintering (SPS) technique. A well-bonded TaC–HfC interface was observed with no apparent cracking and porosity at the joint. The joining mechanisms were predominantly driven by solid-state diffusion and localized plastic deformation. The nanomechanical properties of the TaC-HfC joint are better than the HfC while comparable to that of the TaC. High-load indentation (up to 200 N) results suggest that the TaC–HfC interface is stronger than the parent UHTCs with no crack propagating at the interface. Upon comparison with the parent UHTCs, the damaged area and the average crack length at the interface, reduced up to ~94% and ~56%, respectively. This study shows that the SPS technique can also apply to joining other UHTCs without any filler, resulting in the new field of developing complex components for the thermal protection system (TPS).     

Simultaneously achieved high-energy storage density and efficiency in (K,Na)NbO3-based lead-free ferroelectric films

With the development of advanced electrical and electronic devices and the requirement of environmental protection, lead-free dielectric capacitors with excellent energy storage performance have aroused great attention. However, it is a great challenge to achieve both large energy storage density and high efficiency simultaneously in dielectric capacitors. This work investigates the energy storage performance of sol-gel-processed (K,Na)NbO₃-based lead-free ferroelectric films on silicon substrates with compositions of 0.95(K_0.49Na_0.49Li_0.02)(Nb_0.8Ta_0.2)O₃-0.05CaZrO₃-x mol% Mn (KNN-LT-CZ5-x mol% Mn). The appropriate amount of Mn-doping facilitates the coexistence of orthorhombic and tetragonal phases, suppresses the leakage current, and considerably enhances the breakdown strengths of KNN-LT-CZ5 films. Consequently, large recoverable energy storage density up to 64.6 J cm⁻³ with a high efficiency of 84.6% under an electric field of 3080 kV cm⁻¹ are achieved in KNN-LT-CZ5-5 mol% Mn film. This, to the best of our knowledge, is superior to the majority of both the lead-based and lead-free films on silicon substrates and thus demonstrates great potentials of (K,Na)NbO₃-based lead-free films as dielectric energy storage materials.