TSP观测系统处理参数的研究

近几年,随着国家铁路建设的不断发展,隧道施工越来越多,隧道施工过程中的超前地质预报就担当起了越来越重要的角色,但是在实际测量和数据处理过程中暴露出了越来越多的问题,本文重点对目前国内应用较多的一种超前地质预报技术TSP(tunnel seismic prediction system)的数据处理过程中的几个重点参数进行分析,为数据准确处理和施工指导提供参考.     

Plasticizers derived from cardanol: synthesis and plasticization properties for polyvinyl chloride(PVC)

Two natural plasticizers derived from cardanol (CD), cardanol acetate (CA) and epoxidized cardanol acetate (ECA), were synthesized and characterized by ¹H NMR and ¹³C NMR. The plasticizing effects of the obtained plasticizers on semi-rigid polyvinylchloride (PVC) formulations were also investigated. Two commercial phthalate ester plasticizers, dioctyl terephthalate (DOTP) and diisononyl phthalate (DINP), were used as controls. Mechanical and thermal properties, compatibility, thermal stability, microstructure, and workability were assessed by dynamic mechanical analysis (DMA), mechanical analysis, thermogravimetric analysis (TGA), scanning electron microscopy (SEM), and dynamic stability analysis, respectively. Results indicated that the natural plasticizer ECA had overallsuperior flexibility, compatibility, thermal stability, and workability comparable to both controls. The obtained CA and ECA have lower volatility resistance and similar extraction and exudation resistance than that of DOTP and DINP. The CA was further blended with DOTP in soft PVC films. Results of DMA, TGA and mechanicalanalysis indicated that CA can serve as a secondary plasticizer to improve the related properties of soft PVC formulations. These CD derived plasticizers show promise as an alternative to fully or partially replace petroleum-based plasticizers.     

基于BP网络的曲线拟合法的线图处理

通过实例验证BP神经网络对解析曲线及非解析曲线都非常有效,供开发面向对象的参数化CAD系统时参考.     

基于改进一致性算法的无人机集群饱和攻击

针对无人机一般难以单独打击空防严密的高价值目标问题,采用低成本无人机集群饱和攻击技术,提出协同控制下的三阶段一致性饱和攻击策略,根据不同阶段的任务特点,设计对应的改进一致性算法,并在满足饱和攻击任务多条件协同的基础上,加入Dubins曲线增加飞行轨迹约束,平滑无人机飞行航迹,缩短航程.此外,在高精度队形保持的任务环境下,设计改进的二阶一致性控制器,确保飞行精度,加快收敛速度.最后,将各阶段改进算法的实际效果与传统算法进行对比,在验证改进算法有效性的同时,检验算法延展性.仿真结果表明,该算法可应用于大规模无人机集群并具有良好的效果,为饱和攻击战略决策部署与战术实现提供了依据和参考.     

基于Netty的高性能消息中间件设计与实现

随着互联网业务规模的扩大以及访问量的增多,应用服务可能因流量过大而产生崩溃.为解决此问题和保证应用服务器接收消息的准确性,本文设计了一种基于Netty的消息中间件.该中间件以Netty网络框架为基础实现异步通信,同时为了提升通信双方的编解码速度及缩减整个通信流程的时间,自定义了一种通信协议.该中间件根据本协议特点设计了消费模型及基于文件系统的存储模型,并在消费者端进行了幂等性处理,以提高中间件的可靠性与准确性.实验表明,相比于不使用中间件或使用其它中间件,该中间件在产业化的智慧宿管平台中应用,有效提高了应用服务的响应速率以及接收消息的准确率,保证了智慧宿管平台的平稳运行.     

鄱阳湖滨岸带对N素的净化及其影响因素

以鄱阳湖周边的土壤、水体为研究对象,在调查取样的基础上对典型滨岸带中N素分布及运移进行分析,利用主成分分析法对影响滨岸带对N素净化效果的因素进行排序。结果表明:鄱阳湖滨岸带采样点土壤TN质量比平均值为(0.721±0.275)mg/g,空间差异性大,且周边用地土壤TN质量比普遍高于临水区;水体TN质量浓度表现出周边内陆水体高于近岸湖水、汛前高于汛后的特征;滩地式滨岸带中的土壤TN质量比随滨岸带缓冲宽度增加而减少,且比值普遍低于堤岸式结构;滨岸带结构对N素净化率影响显著,滨岸带的净化效果与结构形式和植被配置有关。     

TDR法、干烧法及烘干法测定土壤含水量的比较研究

以第四纪红壤土为研究对象,采用TDR法、干烧法及烘干法3种方法对不同土层深度的不同梯度土壤含水量进行测定,研究结果表明:干烧法测量值接近烘干法,TDR法测量值比烘干法小,TDR法和干烧法绝对偏差和相对偏差随着土层深度的增加而减小;TDR法和干烧法绝对偏差和相对偏差随着土壤含水量增大而减小,土壤含水量在半湿润条件下偏差较大;TDR法、干烧法与烘干法相关性分别为98.7%和96.4%。本研究结果证实,TDR法和烘干法均能较好的反映土壤水分变化规律,TDR法相对烘干法偏小,使用前有必要进行标定以提高精确度。     

基于相位补偿的任意次谐波有功/无功电流的检测

为了实现更加精细化的谐波分析和治理,需要对任意次谐波电流的有功分量和无功分量进行精确检测。对传统的同步坐标变换法进行了改进,采用park变换构建了电网电压各次谐波的初相位计算方法,根据该初相位构建扩展广义park变换矩阵对电流进行广义park变换,得到各次谐波电流的有功分量和无功分量。设计了改进的检测电路结构并用Matlab/simulink进行了仿真验证,结果表明,该方法可以精确地提取电流有功分量和无功分量,满足任意次谐波细粒度检测的要求。     

基于位移映射的非规则军队标号绘制算法

为了解决三维非规则军标与地形的叠加问题,提出一种基于位移映射的军队标号绘制算法.首先在GPU片元着色器中对地形进行平滑过滤,滤除局部细节而保留地形起伏的主体趋势,将处理结果实时绘制成位移映射纹理;然后由非规则军标的控制点集生成军标二维外轮廓,用之裁剪一次NURBS表面生成平面的军标网格;最后在GPU顶点着色器中依据绑定的位移映射纹理位移军标网格上各顶点,以达到地形匹配的目的.实验结果表明,该算法可使非规则军标合理地匹配上三维地形,且运算效率高,能满足交互编辑以及动态推演的实时要求.     

Synthesis and application of a novel cardanol‐based plasticizer as secondary or main plasticizer for poly(vinyl chloride)

A novel plasticizer based on cardanol, hydrogenated cardanol glycidyl ether acetic ester containing phosphaphenanthrene group (HCGEP), was prepared and incorporated into poly(vinyl chloride) (PVC) for the first time. The molecular structure was characterized with Fourier transform infrared and ¹H NMR spectroscopies. The thermal degradation behavior and flame retardant performance of PVC films with HCGEP as secondary or main plasticizer were investigated using thermogravimetric analysis, combustion tests, limiting oxygen index tests and morphological analysis of residues. Furthermore, the mechanical properties of PVC films were examined based on the results of tensile testing. The results were compared to those of the petroleum‐based plasticizer dioctyl phthalate. With the substitution of dioctyl phthalate with HCGEP, PVC films exhibited high thermal stability and better flame retardant performance. The tensile test results showed that the addition of HCGEP could endow PVC resin with well‐balanced properties of flexibility, strength and hardness. © 2017 Society of Chemical Industry