基于结构层贡献率的沥青路面抗车辙措施

采用环道试验及德国汉堡车辙试验方法,研究在中面层使用改性沥青对路面结构和组合结构抗车辙性能的影响,包括对结构层贡献率和对沥青层剪切流动变形的影响;探讨在中面层添加纤维对路面结构抗车辙能力的影响.研究结果表明:中面层使用改性沥青,能提高路面结构的整体抗车辙性能;使剪切流动变形由95.2%下降至84.4%;中面层变形贡献率达到60%以上,应该重视提高中面层的抗车辙能力;对于中面层采用普通沥青的结构,在中面层添加纤维可明显减少整个结构车辙深度,但对于中面层已采用改性沥青的结构,添加纤维减少车辙的效果不明显.     

Yersinia pestis genome sequencing identifies patterns of global phylogenetic diversity

Plague is a pandemic human invasive disease caused by the bacterial agent Yersinia pestis. We here report a comparison of 17 whole genomes of Y. pestis isolates from global sources. We also screened a global collection of 286 Y. pestis isolates for 933 SNPs using Sequenom MassArray SNP typing. We conducted phylogenetic analyses on this sequence variation dataset, assigned isolates to populations based on maximum parsimony and, from these results, made inferences regarding historical transmission routes. Our phylogenetic analysis suggests that Y. pestis evolved in or near China and spread through multiple radiations to Europe, South America, Africa and Southeast Asia, leading to country-specific lineages that can be traced by lineage-specific SNPs. All 626 current isolates from the United States reflect one radiation, and 82 isolates from Madagascar represent a second radiation. Subsequent local microevolution of Y. pestis is marked by sequential, geographically specific SNPs.     

碱激发胶凝材料的碳化性能研究进展

碱激发胶凝材料作为新型绿色建筑材料,在促进工业固体废料的循环使用、减少CO2气体排放等方面有着突出的优势,近几年针对这种材料耐久性能的研究越发受到重视,碳化作为影响耐久性能的关键因素,也需要进一步的研究。从碳化机理、碳化速率、碳化影响以及抗碳化性能改善方面总结了碱激发胶凝材料碳化性能研究现状,概述了目前碳化领域研究所取得的成果和面临的困难。基于已有成果,提出了研究建议,以期为碱激发混凝土的发展和推广应用提供参考。     

小波降噪方法在电动机故障信号特征提取中的应用

针对油田电动机运行环境恶劣、结构复杂、故障信号中噪声干扰多的特点,采用基于小波变换的降噪方法对电动机故障信号进行特征提取,克服了传统滤波方法的缺陷,为提高电动机故障诊断的精度提供了一个有效工具。同时给出了一个应用实例。     

基于D3D的三维游戏引擎的设计与实现

设计了一种基于Direct3D的三维游戏引擎的框架结构及各个模块的相互关系.并给出了纹理映射、加密解密、GUI的设计、和系统接口的实现方法.     

综述某高层住宅楼的绿色施工

文章结合工程实例,系统地介绍了某高层住宅楼的绿色施工,有一定的推广价值.     

平面艺术设计中的形式美构成探讨

文章从艺术设计的角度,对形式美的构成、形式美共性与特性进行理论上的探讨,并以格式塔心理学为基础,从设计的角度剖析形式法则与视觉心理内在的关联。通过对形式美的理论探讨,促进人们对形式美的认知和理解,进而提升设计者在平面艺术设计中对形式美法则应用的实践。     

基于OMAP5910的出租车无线视频监控系统

将视频监控、GPS和3G技术应用于出租车的远程监控系统，解决了目前基于GSM和GPRS无线信息传输所存在的传输量不足的缺点。     

Effect of KNbO3 content on the crystal structure and electrical properties of (1 − x)PbZr0.54Ti0.46O3-xKNbO3 piezoelectric ceramics

(1 ? x)PbZr_0.54Ti_0.46O₃-xKNbO₃ (0 ≤ x ≤ 25mol%) (abbreviated as PZT-xKN) piezoelectric ceramics were successfully fabricated by a traditional sintering technique at 1225°C for 30 min. The influence of KNbO₃ content on the crystal structure and electrical properties of the PZT-xKN piezoelectric ceramics was studied. Samples with 0 ≤ x ≤ 0.20 show a pure perovskite structure, indicating that all KNbO₃ diffused into the crystal lattice of PZT to form a single solid solution in this compositional range. A second Pb₃Nb₄O₁₃ phase is observed in the PZT-0.25KN sample, showing that the maximum solid solubility of KNbO₃ in PZT matrix ceramic is less than 25mol%. Compared with pure PZT piezoelectric ceramics, samples containing KNbO₃ have smaller crystal grains. PZT-0.15KN exhibits excellent piezoelectric properties with d ₃₃ = 209 pC/N.     

浅谈古建筑设计中的文脉思想

强调建筑文脉,就是更加强调个体建筑是群体的一部分,注重新/老建筑在视觉、心理、环境上的连续性.新旧建筑在建筑造型上不必完全一致取得一定程度的协调,或形体、或色彩、或风格、或气势.建筑物的体量、造型、质感、色彩、装饰、细部处理等方面是与原有建筑协调的关键.