岩矿石电磁频散规律及其在电磁波法勘探中的影响和校正

本文以大量的实测资料为依据,总结了岩矿石电磁频散的规律性。结合电磁波勘探方法中的实际问题,讨论了频散对相位常数α和吸收系数β所产生的影响及误差。提出了在实际工作中对频散进行校正的必要性,并且给出了校正公式。     

用于多频电磁波测井的负阻抗变换式有源接收天线

本文对用负阻抗变换电路同小圆锥螺旋天线相结合,构成的有源接收天线进行了理论分析,并给出了该有源天线稳定工作的条件。结果表明,用该方法设计的有源接收天线具有较宽的频带、较高的灵敏度和较小的尺寸。是多频电磁波测井较理想的接收天线。     

Separation of ocean features from multifrequency full-polarization SAR imagery

Different ocean features usually appear in synthetic aperture radar (SAR) images simultaneously. This makes the image compli- cated and hard to understand. Because of lower signal-to-noise rate , it is much more difficult to separate different ocean features than to separate different land features. A completely novel method is presented to separate ocean features from multifrequency po- larimetric SAR imagery. AIRSAR data from Jet Propulsion Laboratory (JPL), National Aeronautics and Space Administration (NASA) are used in the case studies and good results are achieved.     

多频测深初探

在频率域测深的基础上,提出了多频测深方法,实现一机多频同时观测的目的,以提高观测速度。本文讨论了多频观测方法的理论依据及工作特点,并提示实现这种观测的方案。     

无线寻呼台自动传呼器设计

介绍了一种无线寻呼台自动传呼器的组成、结构和控制软件，利用此设备可以在人工寻呼台中简单，方便地实现自动传呼。     

大底盘双塔结构风振控制研究分析

大底盘多塔超过一定高度时属于复杂超高限结构,这类结构风工程研究多涉及风洞试验或理论研究,过程复杂且应用局限。以宁夏悦海新天地为工程背景,在ETABS建立悦海新天地双塔模型为风控对象。在空间相关性基础上,以自回归过滤技术模拟10a、50a和100a重现期风压下随机脉动风载。由相关资料确定研究对象最不利风向角,在该风向角下动力输入模拟脉动风载。对双塔结构分塔定义,输出T1和T2两个方向风振响应。结合工程提出在设备层布设5种不同黏滞阻尼器位移增效机构,确定最优安装形式。并对比在设备层以最优安装形式布设黏滞阻尼器位移增效机构、顶层布设多调谐质量阻尼器和混合控制法的减振效果。结果表明:3种风振控制措施均有效衰减结构风致振动,其中混合控制法为优控方案。     

利用CSSM进行多频InSAR相位融合及DEM重构

提出了一种基于相关信号子空间处理方法(coherent signal subspace method,CSSM)的多频带InSAR自适应DEM重构方法,采用广义像素模型对各频带InSAR信号建模,再用CSSM中构造聚焦矩阵的思想将多频带相关矩阵变换到参考频率上,然后采用子空间投影方法来估计高程信息。该方法可以在图像配准精度很差(可以允许达到一个分辨单元)的条件下得到稳健的估计性能,仿真数据和SIR-C实际雷达数据验证了此方法的有效性。     

Dielectric relaxation in oil-bearing clayey rocks

The dielectric properties of the bentonite–oil–salt solution mixtures with different water and oil saturation were experimentally studied in the frequency range of 10 kHz to 4 GHz at 25–60 °C. It has been established that besides the region of the Debye water relaxation, there are two more relaxation regions resulting from the interfacial interaction of the mixture components in this frequency range. To describe the dielectric permittivity and equivalent conductivity of the mixture, a spectroscopic model taking into account the multifrequency relaxation is proposed. The dependence of the model parameters on the water saturation and temperatures of the samples has been determined. The experimental data are compared with the modeling results, and the error of prediction for the dielectric permittivity and conductivity of mixture is estimated using the proposed model.     

Evaluation of pinnacle reef distribution at shallow subsurface using integrated geophysical methods: A case study from the upper Kimmeridgian (Spain)

The well exposed outcrops of the upper Kimmeridgian shallow-marine carbonates at Jabaloyas (Iberian Chain, NE Spain) permit the evaluation of geophysical methods for the identification of sedimentary facies. Direct measurement of magnetic susceptibility in facies and detailed grids of magnetometry, electromagnetic multifrequency and ground-penetrating radar (50–500 MHz antennas) have been performed in two study areas where the upper Kimmeridgian rocks are nearly horizontal. Magnetometry indicates negative anomalies in residual magnetic field and vertical magnetic gradient related to reef pinnacles and faults. Electromagnetic data reveal that positive anomalies of apparent conductivity correlate with non-reefal facies. The areal distribution of magnetometry and EM data does not permit the unequivocal identification of pinnacles and faults at the studied area. By contrast, ground penetrating radar profiles and maps of relative reflectivity in two way travel time slices are useful for the identification of faults (hyperbolic anomalies) and reefal and non-reefal facies (radar facies A and B, respectively). The integration of geophysical data, mainly ground penetrating radar, has permitted the 3D reconstruction of reef pinnacles and its tectonic framework.