二维阵列线圈核磁共振地下水探测理论研究

核磁共振法(Magnetic Resonance Sounding,MRS)是一种直接探测地下水的地球物理方法,目前只能对水平层状的含水层进行一维测深,对于尺寸小于线圈直径的二维或三维含水构造成像时,其灵敏度和横向分辨率很低.本文从研究二维阵列线圈核磁共振地下水探测方式的可行性出发,推导了地面发射线圈产生的椭圆极化激发...     

井环境对阵列感应测井响应的影响分析

阵列感应测井资料经常出现与井眼环境有关的质量问题.采用三维矢量有限元法分别在椭圆形井眼、仪器偏心及斜井条件下的阵列感应测井原始响应进行了模拟,并对环境校正和合成聚焦后的数据进行了分析.结果表明,线圈距较短的原始测量信号更易受井眼椭圆度、仪器偏心、泥浆电阻率及与地层电阻率反差的影响;而合成聚焦后的浅探测曲线虽然经过了环境校正和合成聚焦等数据处理,但仍然受这些因素的影响,这反映出阵列感应测井的数据处理是不完善的或采用的校正模型是理想化的;在井斜影响方面,浅探测曲线受井斜角大小影响相对较小,深探测曲线在井斜角为60°以上时受其影响较大而必须进行进一步处理.     

A Simple Model Of Software Costs For The Square Kilometre Array

Software costs for radio telescopes have nearly always been underestimated. Since the Square Kilometre Array is often called a software telescope, repeating the usual error would be particularly egregious. We estimate software costs by scaling from the reasonably well-known costs for the Atacama Large Millimeter Array. The resulting model has sharp dependency on the complexity of the SKA, suggesting the obvious – that software costs can most easily be limited by constraining the scientific and operational requirements. A bottom-up costing will not be possible until SKA is much more clearly defined. For the moment, we recommend that 20% of the SKA budget be allocated to software development.     

Isolation of differentially expressed genes from contaminant exposed European flounder by suppressive, subtractive hybridisation

Commercially farmed European flounder (Platichthys flesus) were treated with benzo[a]pyrene or cadmium under controlled laboratory conditions. In addition, animals were collected from the polluted Tyne and relatively clean Alde estuaries in the UK. Potential differentially expressed genes were isolated from liver tissue by means of suppressive, subtractive hybridisation. A total of 284 different mRNAs were identified as having the potential for being differentially expressed, of which 84 could be tentatively identified by homology with database sequences. These clones will form part of a flounder cDNA array for validation and future applications, with full identification being pursued for those expressed sequence tags for which differential expression can be confirmed by array technology.     

Research on the Result of Calibration for the Location of the Seismic Array in Shanghai

The paper proposes the calibration theory and methods for the Shanghai seismic array and analyzes the calibration results. As a result, the calibration results for the seismic array based on 2 typical earthquakes have been drawn; the difference of calibration results between Hokkaido and Honshu region in Japan is investigated. And calibration results of different directions, different epicenter distances and different magnitudes are probed into. The result shows that the location of earthquakes on the Shanghai seismic array is greatly improved.     

上海台阵标定方法的对比研究

本文介绍了基于台阵标定理论建立的上海台阵标定数据库;提出了最近标定和平均标定的方法。通过典型的地震事件对新方法进行了校验,结果表明最近标定和平均标定法的标定效果都比较好,有效的提高了地震定位精度。     

Calculation and analysis of correlation curves between Lanzhou Seismic Array sites and assessment of primary array

Introduction After the field survey for the building of Lanzhou Seismic Array, Dajian Mountain that is lo-cated 18 km on the southwest of Lanzhou Seismic Station was chosen as the array address among the several eligible areas. Lanzhou Array address is situated on the Wusu Mountain range with the stable base rocks, and no large active faults are found nearby. During the site survey, we made a 18-day field observation at Dajian Mountain array address in Lanzhou by using a set of FBS-3A b…     

兰州台阵勘址测点相关值曲线的计算分析与初选台阵评估

利用兰州台阵勘址观测中方的资料，对勘址测点的信号与噪声的相关值进行了计算与分析，结果得出检测PG与P震相的最佳内外环半径分别为380 m和1 500 m．根据台阵内外环半径的计算结果，以及内外环子台不要按放射状排列的要求，从勘址测点中选出了满足背景噪声水平要求的9个子台作为初选台阵，并对初选台阵进行了评估． 结果表明，此初选台阵的定位能力与检测能力均达到规定的标准．      

Vla and Spacecraft Observations of Solar Activity

We describe the world's largest synthesis radio telescope, the Very Large Array (VLA), and how it can be used to complement observations with the Solar and Heliospheric Observatory (SOHO) and the Yohkoh solar spacecraft. The VLA provides images with high spatial and temporal resolution, often across the visible solar disk. The VLA also detects nonthermal radiation that is not observed with SOHO and Yohkoh, and provides estimates for the coronal magnetic field strengths that are not directly measured by these spacecraft. The VLA data can be combined with SOHO CDS, SOHO EIT, or Yohkoh SXT observations to provide new insights to the compact, variable sources, called blinkers and bright points, in the solar transition region or low corona. A new 400 cm VLA system provides images of nonthermal burst activity associated with Coronal Mass Ejections (CMEs), and may detect thermal emission from CMEs, that can be compared with SOHO's LASCO and EIT instruments to obtain new information about the origin and evolution of CMEs.