基于证据理论的TPS诊断性能综合评定

测试程序集TPS(Test Program Set)诊断性能的评定是保证TPS质量的重要手段.针对TPS诊断性能的评定问题,研究了基于D-S(Dempster-Shafer)证据理论的综合评定方法,介绍了D-S证据理论的基本原理,提出了TPS评价验证的数学模型以及基于证据理论的TPS诊断性能综合评定的基本框架,定义了TPS诊断性能的基本概率分配函数(BPAF,Basic Probability Assignment Functions),并在此基础上提出了基于Kolmogorov-Smimov(K-S)检验的BPAF确定方法,给出了TPS诊断性能综合评定的步骤,最后对基于D-S证据理论的TPS诊断性能综合评定的有效性进行了实例分析,结果证明了该方法的有效性.      

网络连接机群上CFD计算的一种负载平衡方法

讨论在网络连接的分布式存储并行机群上进行CFD计算的一种负载平衡方法和相关问题。当数值计算的方法是区域分解法时,各节点机上的负载与其处理的子区域的网格节点数成正比,所以同样大小的子区域可保证负载平衡。采用负载再分配即区域再剖分的方法来达到动态负载平衡,构造了一种对多块网格(每块内为结构网格但各块间的连接关系可以是非结构的)进行近似平均分划的方法,并用一种数据结构和算法保证了剖分出的多个子区之间正确的互联和边界信息传递关系。给出了用这种剖分算法对常见多块网格进行分划的例子,并对三维流场进行了实际计算。结果证明本文方法是正确的,能有效地均衡计算负载,达到较理想的并行效率。     

基于工程实践的民机金属结构ADR确定方法研究

偶然损伤额定值（ADR）的确定主要依赖用户（航空公司）和设计部门的经验。本文在对民机结构偶然损伤额定值（ADR）体系做简介的基础上,针对如何通过工程实践确定影响ADR的各因素指标等级,给出了采集工程实践数据的方法,以及统计数据的处理方法,确定出各指标等级。以前起落架舱壁板为例,确定出其ADR及检查间隔,结果与实际相符,验证了方法的正确性,为民机初始维修大纲的制定提供一种有效的方法。     

Heading south with a north-up map: A choice processing analysis of map alignment effects

This study employed an information accumulation model of choice reaction times to investigate alignment effects in mental representations of maps. University students studied a map from a single orientation (with north at the top). In a subsequent two-choice reaction time task, the students’ spatial knowledge of the map was assessed employing spatial left/right judgments, which were made from imagined perspectives that were either north-aligned or south-aligned. Data showed a standard alignment effect, favoring north- over south-aligned trials. To examine the locus of this effect, data were fit using the Linear Ballistic Accumulator (LBA) model of speeded decisions (Brown & Heathcote, 2008). Of interest were three model parameters: drift rate, the speed at which evidence accumulates toward a response; response threshold, the amount of evidence demanded from the decision maker before selecting a response; and non-decision time, the time consumed by pre- and postdecisional processes. The best-fitting model suggested that non-decision time accounted for the alignment effect. The difference in non-decision time between north and south-aligned judgments suggests a mental alignment stage on south-aligned trials, accounting for the longer reaction times for judgements misaligned with the presented north orientation of the map.     

TMS320C6678 多级程序加载模式的实现

为了对实地、多单元部署的TMS320C6678 产品同时提供独立启动、就地调试、远程加载功能，利 用TMS320C6678 片上多种通讯接口和资源，联合片上固化的内置加载核，设计和实现了一种灵活可配置的多 级程序加载模式，满足应用需求。     

ATLAS程序语言结构分析

以波音737飞机装备的FMC为例，详细分析和介绍ATLAS语言测试程序的组成、结构及其定界标志，可为涉及相关工作的技术人员提供参考。     

基于非结构动网格的非定常流数值模拟方法

给出了基于非结构动网格的非定常流动问题的数值模拟方法,重点说明两种动态非结构网格方法的原理以及在非定常流模拟中的算法.一种是基于非结构网格的重叠网格方法,该方法结合了非结构网格方法和重叠网格方法的优点,以物面距为准则参数对网格节点进行分类,进而建立重叠网格的网格问插值关系,通过采用动态非结构重叠网格算法,可以处理多体间...     

Experimental and Numerical Investigation of the Effects of Passive Vortex Generators on Aludra UAV Performance

A study of the effects of passive vortex generators (VGs) on Aludra unmanned aerial vehicle (UAV) aerodynamic characteristics is presented. Both experimental and numerical works are carried out where an array of VGs is attached on Aludra UAV’s wing. The flow measurements are made at various angles of attack by using 3-axis component balance system. In the numerical investigation, the Reynolds-averaged Navier-Stokes (RANS) code FLUENT 6.3TM is used in the simulations with fully structured mesh with Spalart-Allmaras (S-A) turbulence model and standard wall function. The comparison between the experimental and numerical results reveals a satisfactory agreement. The parametric study shows that higher maximum lift coefficient is achieved when the VGs are placed nearer to the separation point. In addition to this, shorter spanwise distance between the VGs also increases the maximum lift coefficient, rectangular and curve-edge VG performs better than triangular VG.     

基于案例推理的民用飞机系统维修间隔确定方法研究

制定合理有效的维修方案．是保持飞机安全性和经济性的重要手段。维修方案中规定了各系统的维修类型和维修间隔,由于各系统的维修类型相对固定,所以维修间隔的确定是制定维修方案的关键。本文采用了基于案例推理技术的方法来确定系统维修间隔,重点研究了案例知识的表达和案例的调整．并以波音737的部件使用可靠性数据为例．对本方法进行了验...     

基于能量法的舰载机拦阻着舰动力学分析及建模仿真

针对舰载机拦阻着舰过程,采用能量法分析了任意着舰姿态和位置下的拦阻力响应,建立了全机六自由度动力学模型,考虑了航母甲板风的影响以及航母纵摇和升沉运动。通过MATLAB／SIMULINK建立数学模型,并以一种偏心非垂直着舰拦阻状态为算例进行了仿真分析。