An analysis and enhanced proposal of atmospheric boundary layer wind modelling techniques for automation of air traffic management

The air traffic management automation imposes stringent requirements on the weather models, in such a way that they should be able to provide reliable short-time forecasts in digital formats in almost real time. The atmospheric boundary layer is one of the regions where aircraft operation and coordination are critical and therefore atmospheric model performance is also vital. This paper presents conventional and innovative techniques to improve the accuracy in the forecasting of winds in the lower atmospheric layer, proposing mechanisms to develop better models including deterministic and stochastic simulations. Accuracy is improved by optimizing the grid, assimilating observations in cycling simulations and managing a number of ensemble members. An operation-driven post-processing stage helps to incorporate detailed terrain definitions and real-time observations without re-running the model. The improvements are checked against mesoscale weather simulations at different scales and a dedicated flight campaign. The results show good performance of the model without sensitively increasing the required throughput.     

多层CT用数据采集系统的设计与测试

提出了一种多通道、高密度、高精度数据采集系统的设计方案.采用基于现场可编程逻辑门阵列(FPGA, Field Programmable Gate Arrays)内嵌软核的体系结构,实现了多通道数据的缓冲、格式转换、乒乓读写等流水操作,解决了多层CT(Computed Tomography)有限扫描时间内数据量大、时序要求严格和数据传输精确性要求高的问题;同时利用高精度电压源和精密电阻模拟了前端输入,设计了基于PXI(PCI eXtensions for Instrumentation)总线的虚拟仪器,精确测试了设计系统的性能且未额外引入噪声.方案已成功应用于多层CT中,同时也为数据采集提供一种借鉴.      

高精度力值计量巡回标准的研制

摘要根据巡回标准的特殊要求,以应用实例详细介绍了高精度力值计量巡回标准的研制方案。实例中采用McS51单片机、∑-△型A／D芯片、精密参考电源、液晶显示屏模块等,经对数据采集部分的分析估算,得出该标准具有1×10^-4的高精度,分辨率可达满量程的1．2×10^-7。具有结构简单、成本低、接口方便、便携等优点。     

CDAS 20m 天线分系统设计

ＣＤＡＳ天线分系统主要由天线机械结构、馈电网络、天线控制及微机监控几部分组成。天线采用２０ｍ卡塞格伦式天线,馈源为波纹喇叭,多模单脉冲自跟踪方案;利用轴角编码器构成伺服位置环;由三相可控硅功放及伺服直流电机驱动天线;双电机克服齿隙影响;天线具有多种工作方式,操控方便;监控微机对系统统一监控并完成故障实时在线检测功能。     

固体火箭发动机试验测量系统零位变化研究

介绍了测试系统推力测量中常见的零位变化现象,对零位变化的原理进行了分析,并提出了针对性的数据处理方法。     

一种用于热校准风洞的数据采集系统集成及软件设计

简要介绍了研华ＡＤＡＭ４０００系列模块的性能及其特点,并详细阐述了利用该系列模块组成一种用于热校准风洞的数据采集秕 及ＬＡＢＴＥＣＨＣＯＴＲＯＬ组态软件包在整个中的应用。     

高速率遥感卫星接收与处理系统的设计与实现

为成功接收搭载分米级分辨率的SAR（Synthetic Aperture Radar,合成孔径雷达）载荷低轨遥感卫星数据,验证卫星载荷工作状态和性能,本项目研发一套Ka/S双频段遥感卫星接收与处理机动站。针对窄波束高动态卫星跟踪、多通道高速率遥感数据星地传输的重难点,本文着重从窄波束高动态目标卫星跟踪、超高速高性能全数字解调以及高精度双模式自适应盲均衡等关键技术进行研究。通过试验验证技术路径正确、措施有效,可为后续相关系统研制提供技术参考。     

航天器空投试验用大容量数据记录器的研究

在航天器空投试验中,数据记录器需要长时间高速采集试验数据,并将试验数据保存起来。记录器还要满足体积小和抗着陆冲击等恶劣环境的要求。文章介绍了数据记录器的特点、主要功能,硬件选型及软件设计等。提供了一种利用嵌入式技术来构成大容量高速率航天器空投试验用数据记录器的方法。     

A combined technique of Kalman filter,artificial neural network and fuzzy logic for gas turbines and signal fault isolation

The target of this paper is the performance-based diagnostics of a gas turbine for the automated early detection of components malfunctions. The paper proposes a new combination of multiple methodologies for the performance-based diagnostics of single and multiple failures on a two-spool engine. The aim of this technique is to combine the strength of each methodology and provide a high success rate for single and multiple failures with the presence of measurement malfunctions. A combination of KF (Kalman Filter), ANN (Artificial Neural Network) and FL (Fuzzy Logic) is used in this research in order to improve the success rate, to increase the flexibility and the number of failures detected and to combine the strength of multiple methods to have a more robust solution. The Kalman filter has in his strength the measurement noise treatment, the artificial neural network the simulation and prediction of reference and deteriorated performance profile and the fuzzy logic the categorization flexibility, which is used to quantify and classify the failures. In the area of GT (Gas Turbine) diagnostics, the multiple failures in combination with measurement issues and the utilization of multiple methods for a 2-spool industrial gas turbine engine has not been investigated extensively.This paper reports the key contribution of each component of the methodology and brief the results in the quantification and classification success rate. The methodology is tested for constant deterioration and increasing noise and for random deterioration. For the random deterioration and nominal noise of 0.4%, in particular, the quantification success rate is above 92.0%, while the classification success rate is above 95.1%. Moreover, the speed of the data processing (1.7 s/sample) proves the suitability of this methodology for online diagnostics.     

一种针对液体火箭发动机可靠性的双线评估方法

针对液体火箭发动机可靠性评估过程中试验数据利用不充分、主观性强、与设计改进关联不足等现状,给出了一种可靠性双线评估方法,在有限试车条件下提升可靠性评估结果的准确性,并从风险控制角度识别出发动机的薄弱环节.该方法采用两条主线开展可靠性评估,第一条线以发动机部组件试验数据为输入,以发动机工作时序为线索,识别发动机故障模式,...