基于PDXP协议的数据监视软件的设计实现

基于UDP（用户数据报协议）组播数据传输方式,通过对接收到数据包中相关PDXP（包数据交换协议）字段的实时解析和挖掘分析,采用BackgroundWorker（后台工作者线程）模型简化多线程交互方式,以分级缓存为基础优化数据存储结构,通过直接调用GDI（图形设备接口）＋绘图接口设计开发高效的UI（用户接口）显示控件,并且利用Linq（语言级集成查询）数据访问技术,以可视化的形式对PDXP数据包的丢包和乱序等问题进行实时判读和基于源码的分析,提供了一种对中心之间交互的数据进行实时连续性监视分析的简捷、直观和有效的途径。     

涡喷发动机多变量自适应加速控制

提出了一种模型参考自适应控制方法, 并应用于双转子涡喷发动机多变量控制系统。仿真研究表明, 该方法在整个飞行包线内均有满意的瞬态响应, 对非线性的建模不确定性具有较好的鲁棒性, 以及对多变量系统中较强的耦合作用有较好的解耦效果。与传统的调节器相比, 发动机加速时间约减少16%, 加速过程中发动机推力明显增加, 平衡状态仍可提高约9%。      

UML软件开发过程和支持环境研究

从当前对软件工程过程的需求出发,结合软件工程领域的最新成果统一建模语言UML(Unified Modeling Language),重点讨论了适应需求变化的迭代式软件开发过程,提出了柔性软件开发模型.在此研究的基础上,设计了集成化UML软件开发环境的框架,指出其组成应包括UML可视化建模系统、UML模拟系统、UML代码生成系统和UML逆向变换系统4个部分,并提出了需要解决的问题.     

利用校准卫星进行USB外场试验的方法

探讨一种USB外场试验的方法,即利用在轨卫星对USB进行外场试验,检验设备的跟踪性能,并对测量精度进行评估。阐述在USB设备研制过程中,利用卫星对USB进行外场试验的必要性和可行性。     

Best practices for model-based and simulation-aided engineering of power transmission and motion control systems

This paper deals with the modelling and simulation of aircraft systems, in particular for power transmission and control. It is intended to review, propose and disseminate best practices for making model-based/simulation-aided engineering more efficient at any phase of the system life cycle. The proposals are aimed at creating value, not only by increasing the performance of the product under study but also by shortening the time to market, capitalizing knowledge, mitigating risks and facilitating concurrent engineering. The needs associated with the engineering activities are firstly identified to define a set of requirements for the models. Then, these requirements are used to drive the considerations leading to model development, focusing in particular on the process, modelled physical effects, modelling level, model architecting and concurrent engineering. The third part deals with the model implementation, giving special consideration to the different types of models, causalities, parameterization, implementation and verification. Each part is illustrated by examples related to safety critical actuators.     

多GPU并行可压缩流求解器及其性能分析

为实现可压缩流问题的大规模高效数值求解,开展基于图形处理单元（GPU）的并行计算研究。在NVIDIA GTX 1070上建立了基于消息传递接口+统一计算设备架构（MPI+CUDA）的多GPU并行可压缩流求解器,该求解器基于结构网格有限体积法,空间离散采用AUSM⁺UP格式。采用一维区域分解法对计算网格进行划分,使得各GPU之间达到负载平衡。针对超声速进气道算例,对算法单GPU并行性能和多GPU可扩展性能进行分析。数值结果显示,单GPU并行计算可以获得37~46倍的加速比,极大地提高了计算效率;4块GPU并行计算加速比从47倍增加到143倍,并行效率维持在70%以上,说明并行算法具有良好的可扩展性。     

Modelling and simulation of flight control electromechanical actuators with special focus on model architecting,multidisciplinary effects and power flows

In the aerospace field, electromechanical actuators are increasingly being implemented in place of conventional hydraulic actuators. For safety-critical embedded actuation applications like flight controls, the use of electromechanical actuators introduces specific issues related to thermal balance, reflected inertia, parasitic motion due to compliance and response to failure. Unfortu-nately, the physical effects governing the actuator behaviour are multidisciplinary, coupled and nonlinear. Although numerous multi-domain and system-level simulation packages are now avail-able on the market, these effects are rarely addressed as a whole because of a lack of scientific approaches for model architecting, multi-purpose incremental modelling and judicious model implementation. In this publication, virtual prototyping of electromechanical actuators is addressed using the Bond-Graph formalism. New approaches are proposed to enable incremental modelling, thermal balance analysis, response to free-run or jamming faults, impact of compliance on parasitic motion, and influence of temperature. A special focus is placed on friction and compliance of the mechanical transmission with fault injection and temperature dependence. Aileron actuation is used to highlight the proposals for control design, energy consumption and thermal analysis, power net-work pollution analysis and fault response.     

提高大学生读写能力之策略

本文着重论述了加强语言基础训练和培养语篇阅读能力是提高大学生读写能力的有效途径。指出两者是相互促进、相辅相成的的关系。同时，就如何提高大学生的读写能力提出了一些方法和策略。     

The fast debris evolution model

The ‘particles-in-a-box’ (PIB) model introduced by Talent [Talent, D.L. Analytic model for orbital debris environmental management. J. Spacecraft Rocket, 29 (4), 508–513, 1992.] removed the need for computer-intensive Monte Carlo simulation to predict the gross characteristics of an evolving debris environment. The PIB model was described using a differential equation that allows the stability of the low Earth orbit (LEO) environment to be tested by a straightforward analysis of the equation’s coefficients. As part of an ongoing research effort to investigate more efficient approaches to evolutionary modelling and to develop a suite of educational tools, a new PIB model has been developed. The model, entitled Fast Debris Evolution (FADE), employs a first-order differential equation to describe the rate at which new objects ?10 cm are added and removed from the environment. Whilst Talent [Talent, D.L. Analytic model for orbital debris environmental management. J. Spacecraft Rocket, 29 (4), 508–513, 1992.] based the collision theory for the PIB approach on collisions between gas particles and adopted specific values for the parameters of the model from a number of references, the form and coefficients of the FADE model equations can be inferred from the outputs of future projections produced by high-fidelity models, such as the DAMAGE model.     

图式理论在第二语言习得中的作用

本文通过对图式理论的阐述 ,分析学生在英语学习中所面临的重大障碍 ,进一步阐明这些障碍所产生的根源。从而归结出图式理论在学生从事第二语言习得时所起的重要作用。倡导教育工作者对学生的图式进行编码、解码、重构码 ,最终帮助学生建立其英语国家人们学习英语时运用的图式