嵌入式GPS/DR车载组合导航系统EKF算法软件设计

介绍一种嵌入式GPS／DR（全球定位系统／航位推算）车载组合导航（它通过GPS与DR的优势互补,提高了车辆导航系统定位数据的可靠性）的EKF（扩展卡尔曼滤波）算法软件设计方法。采用统计学原理剔除导航数据的粗差点,用扩展卡尔曼滤波进行导航参数的实时求解,采用EKF算法的GPS／DR组合导航系统有利于导航信息的稳定性、可靠性和实时性。     

Hα measurements using DEFPOS/RTT150 Telescope： Instrumentation and observations

To investigate the physical properties of HII regions and some PNe about 4' in size, a DEFPOS Fabry-Perot spectrometer has been redesigned and set up at the (Antalya/Bakirlitepe, Turkey), The spectrometer has a 4' circular field of view and a velocity resolution of 27.27 km s- 1 (a spectral resolving power of 11000) over a 200 km s-1 spectral window near Hα. This work presents the details of the newly redesigned inphysical results of our new Hα observations selected from the Reynolds et al. (2005) and Fich et al. (1990) papers. The DEFPOS system has been fully tested and the first observations of HII regions and PNe in the Galaxy are used to illustrate the power of the instrument. We feel that our first Fabry-Perot observations can provide a powerful tool for the study of objects with small angular size. In the future, we are planning to prepare a catalog including some physical properties such as radial velocity, line width, and intensity of some PNe and HII regions close to the 4' field of view.     

IAGA模型支持下的灾区基站组网优化

根据矿井、失火办公大楼等灾区自然环境特征,结合基站信号多重覆盖的特点,提出了一种改进自适应遗传算法（IAGA）,对基站组网部署进行优化。首先介绍灾害环境下的时间到达差算法（TDOA）,用精度因子（DOP）刻画精度指标,提出了基站组网部署原则,以定位综合性能作为目标函数求解基站坐标。仿真试验表明,IAGA模型能够较好地应用于应急组网优化的部署,该算法基本能够达到最优解或次优解。     

基于调和分析法与ANFIS系统的综合潮汐预报模型

港口沿岸地区以及河流入海口等地区的精确潮汐预报对于各种海洋工程作业有着非常重要的意义。潮汐水位的变化受到众多复杂因素的影响,而且这些复杂的因素往往有着较强的实变性和非线性。为了进一步提高沿岸港口码头等水域的潮汐水位的预测精度,本文提出了一种基于调和分析模型与自适应神经模糊推理系统相结合的模块化潮汐水位预测模型;并采用相关分析确定整个预测模型的输入维数;模块化将潮汐分解为两部分：由天体引潮力形成的天文潮部分和由各种天气以及环境因素引起非天文潮部分。其中调和分析法用于天文潮部分的预测,ANFIS用于预测具有较强非线性的非文潮部分。模块化综合了两种方法的优势,即调和分析法能够实现长期、稳定的天文潮预报,ANFIS能够以较高的精度实现潮汐非线性拟合与预测。模型使用ANFIS模型和调和分析模型分别对潮汐的非天文潮和天文潮部分进行仿真预测,然后将两部分的预测结果综合形成最终的潮汐预测值。此外,本文选用三种不同的模糊规则生成方法（grid partition （GP）,fuzzy c-means （FCM） and sub-clustering （SC））生成完整的ANFIS系统,并使用实测数据进行验证用以选取最优的ANFIS预测模型。最后将最优的ANFIS模型与调和分析模型相结合进行潮汐水位的最终预报。仿真实验选用Fort Pulaski潮汐观测站的实测潮汐值数据进行预报的仿真实验,仿真结果验证了该模型的可行性与有效性并取得了良好的效果,具有较高的预报精度。     

Sequential Filtering for Surface Wind Speed Estimation from Ambient Noise Measurement

Many research results show that ocean ambient noise and wind speed are highly relevant, and the surface wind speed can be effectively inverted using ocean noise data. In most deep-sea cases, the ambient noise of medium frequency is mainly determined by the surface wind, and there is a conventional relationship between them. This paper gives an equation which shows this relationship firstly, and then a surface-wind inversion method is proposed. An efficient particle filter is used to estimate the speed distribution, and the results exhibit more focused close to the actual wind speed. The method is verified by the measured noise data, and analysis results showed that this approach can accurately give the trend of sea surface wind speed.     

Fast computation of 2D transfer functions from adaptive optics data

The use of atmospheric transfer functions is common in image reconstruction techniques such as speckle interferometry to calibrate the Fourier amplitudes of the reconstructed images. Thus, an accurate model is needed to ensure proper photometry in the reconstruction. The situation complicates when adaptive optics (AO) are used during data acquisition. I propose a novel technique to derive two‐dimensional transfer functions from data collected using AO simultaneously with the observations. The technique is capable to compute the relevant transfer functions within a short time for the prevailing atmospheric conditions and AO performance during data acquisition (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)     

SUNRISE – Impressions from a successful science flight

SUNRISE is a balloon‐borne telescope with an aperture of one meter. It is equipped with a filter imager for the UV wavelength range between 214 nm and 400 nm (SUFI), and with a spectro‐polarimeter that measures the magnetic field of the photosphere using the Fe I line at 525.02 nm that has a Landé factor of 3. SUNRISE performed its first science flight from 8 to 14 June 2009. It was launched at the Swedish ESRANGE Space Center and cruised at an altitude of about 36 km and geographic latitudes between 70 and 74 degrees to Somerset Island in northern Canada. There, all data, the telescope and the gondola were successfully recovered. During its flight, Sunrise achieved high pointing stability during 33 hours, and recorded about 1.8 TB of science data. Already at this early stage of data processing it is clear that SUNRISE recorded UV images of the solar photosphere, and spectropolarimetric measurements of the quiet Sun's magnetic field of unprecedented quality (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)     

Determination of the Angle of Shearing Resistance of Soils Using Multivariate Adaptive Regression Spline

This article adopts Multivariate Adaptive Regression Spline (MARS) for prediction of Angle of Shearing Resistance(?) of soil. MARS is an adaptive, non-parametric regression approach. Percentages of fine-grained (FG), coarse-grained (CG), liquid limit (LL), and bulk density (BD) have been used as input variables of MARS. The developed MARS gives an equation for prediction of ? of soil. The results of MARS have been compared with Genetic Expression Programming (GEP), Artificial Neural Network (ANN), and Adaptive Neuro Fuzzy Inference System (ANFIS) models. These results demonstrate that the developed MARS can be used as a robust model for determination of ? of soil.     

精密单点定位的一种低动态解法

采用自适应选权滤波法,对低动态精密单点定位的解算方法进行研究,并编写了精密单点定位程序。通过合理选择自适应因子参数,对船载动态GPS测量数据进行了事后精密单点定位处理。结果表明:相对于经典卡尔曼滤波方法,采用自适应选权滤波法可大大提高低动态精密单点定位解的精度,X、Y、Z三个方向的RMS分别提高了79.9%、69.7%和92.0%。     

海道测量中余水位分离方法的研究

证明了基于余水位信息进行海洋潮汐推算时不需考虑测量区域内潮汐性质是否相似;计算了中数法、陈宗镛法、Rossiter法、Doodson法、Godin法关于63个主要分潮的滤波器谱数值,从理论上对各模型滤波能力进行了量化表征;基于上述滤波法进行了仿真和实测水位的余水位分离计算。结果表明,Godin法可基本消除实测水位的短周期分潮影响,若进一步消除其隐含的中、长周期分潮影响,则Godin法在海道测量水位改正中将有更大应用价值。