测井仪器的故障分析与排除思路     

邓红旗  陆勇 《中国煤炭地质》2008,(12):46-48

TYSC-3Q与PSJ-2型数字测井仪是目前煤田测井中常用的二种测井仪器,在使用过程中难免发生诸如测井控制故障、声速探管故障、密度三侧向探管故障、井温、井液电阻率探管故障、电法面板故障、数字测井面板故障、电测井故障等常见故障类型。通过对各类故障因素进行剖析,指出了故障易发生的部位,并详细的介绍了检查的方法及故障的排除步骤。  相似文献   

The gravitational field of topographic-isostatic masses and the hypothesis of mass condensation II-the topographic-isostatic geoid     

J. Engels  E. W. Grafarend  P. Sorcik 《Surveys in Geophysics》1996,17(1):41-66

In Part I we focussed on a convergent representation of the gravitational potential generated bytopographic masses on top of the equipotential surface atMean Sea Level, thegeoid, and by those masses which compensate topography. Topographic masses have also been condensated, namely represented by a single layer. Part II extends the computation of the gravitational field of topographic-isostatic masses by a detailed analysis of itsforce field in terms ofvector-spherical harmonic functions. In addition, the discontinuous mass-condensated topographic gravitational force vector (head force) is given. Once we identify theMoho discontinuity asone interface of isostatically compensated topographical masses, we have computed the topographic potential and the gravitational potential which is generated by isostatically compensated masses atMean Sea Level, the geoid, and illustrated by various figures of geoidal undulations. In comparison to a data oriented global geoid computation ofJ. Engels (1991) the conclusion can be made that the assumption of aconstant crustal mass density, the basic condition for isostatic modeling, does not apply. Insteaddensity variations in the crust, e.g. betweenoceanic and continental crust densities, have to be introduced in order to match the global real geoid and its topographic-isostatic model. The performed analysis documents that thestandard isostatic models based upon aconstant crustal density areunreal.  相似文献   

Overbreak and underbreak in underground openings Part 2: causes and implications   总被引：7，自引：0，他引：7  

J. A. Ibarra  N. H. Maerz  J. A. Franklin 《Geotechnical and Geological Engineering》1996,14(4):325-340

Summary The newly developed light sectioning method has been used to investigate some of the causes and costs of overbreak and underbreak. Investigations at the Aquamilpa Hydroelectric Project in Mexico have shown decreased overbreak and increased underbreak as a result of increased rock quality and decreased explosive energy. A new measure of explosive energy, the perimeter powder factor (PPF), has been defined and shown to be useful in the context of tunnel-wall rock damage. Tentative results indicate that explosive energy (PPF) may be a more important factor in producing underbreak, whereas rock quality may be a greater factor in producing overbreak. A site-specific equation is given for predicting overbreak or underbreak as a function of rock quality and explosive energy, with an evaluation of the cost of underbreak and overbreak.  相似文献   

Passing through resonance: The excitation and dissipation of the lunar free libration in longitude     

Donald H. Eckhardt 《Celestial Mechanics and Dynamical Astronomy》1993,57(1-2):307-324

The acceleration of the mean lunar longitude has a small effect on the periods of most terms in a Fourier expansion of the longitude. There are several planetary perturbation terms that have small amplitudes, but whose periods are close to the resonant period of the lunar libration in longitude. Some of these terms are moving toward resonance, some are moving away from resonance, and the periods of those terms that do not include the Delaunay variables in their arguments are not moving. Because of its acceleration of longitude, the Moon is receding from the Earth, so the magnitude of the restoring torque that the Earth exerts on the rotating Moon is gradually attenuating; thus resonance itself is moving, but at a much slower rate than the periods of the accelerating planetary perturbations. There are five planetary perturbation terms from the ELP-2000 Ephemeris (with amplitudes of 0.00001 or greater) that have passed through resonance in the past two million years. One of them is of special interest because it appears to be the excitation source of a supposed free libration in longitude that has been detected by the lunar laser ranging experiment. The amplitude of the term is only 0.00021 but it could be the source of the 1 amplitude free libration term if the viscoelastic properties of the Moon are similar to those of the Earth.  相似文献   

基于立体补偿的遥感立体像对压缩方法     

李飞鹏  马国锐  秦前清  李德仁 《遥感学报》2005,9(2):195-203

提出研究遥感立体像对的压缩问题。主要讨论了左右影像的视差补偿和辐射补偿。针对遥感立体像对视差分布不均以及左右影像存在辐射差的特点,提出了一种基于立体补偿的遥感立体像对压缩算法。该算法以左片为基准图像,采用自适应视差估计计算出右片的视差矢量,结合辐射校正和重叠块视差补偿技术得到平滑的右片的预测图像,以右片减去预测图像得到残差图像,然后采用小波压缩算法对残差图像进行压缩。实验结果表明,该算法能显著提高遥感立体像对的压缩性能。  相似文献   

DAS24-3B数据采集系统采集控制模块的工作原理     

侯广兵  倪大来 《地球物理学进展》2002,17(4):715-721

DAS24-3B是中国科学院地质与地球物理研究所研制的宽频带地震数据采集系统。采集控制模块是该系统的重要组成部分。本文阐述了控制模块的工作原理，介绍了DAS24-3B系统的基本组成和采集器工作过程，并给出该系统如何与笔记本端应用程序界面通讯和联络的操作建议，使该系统能够在工作中发挥更大的作用。  相似文献   

高压铁芯串联电抗器烧损故障分析   总被引：1，自引：0，他引：1       下载免费PDF全文

魏志新  侯建军  王立成 《地质找矿论丛》2003,18(Z1):152-154

分析了高压铁芯串联电抗器烧损的原因,进一步探讨了V-A特性对铁芯串联电抗器的影响,以及电抗率的选取.  相似文献   

Distribution of L_g coda Q in the Chinese continent and its adjacent regions     

丛连理  胡家富  傅竹武  温一波  康国发  吴小平 《中国科学D辑(英文版)》2003,46(6)

In continent Lg is usually one of the predominant phases recorded by short-period or broad-band seismometers. A ray-theoretical approach shows that Lg wave is the superposition of higher-mode surface waves propagating in the continental crust[1—4]. The g…  相似文献   

Anelastic structure of the upper mantle beneath the northern Philippine Sea     

Azusa Shito  Takuo Shibutan 《Physics of the Earth and Planetary Interiors》2003,140(4):319-329

We investigated the upper mantle anelastic structure beneath the northern Philippine Sea region, including the Izu-Bonin subduction zone and the Shikoku Basin. We used regional waveform data from 69 events in the Pacific and the Philippine Sea slabs, recorded on F-net and J-array network broadband stations in western Japan. Using the S–P phase pair method, we obtained differential attenuation factors, δt^*, which represent the relative whole path Q. We conducted a tomographic inversion using 978 δt^* values to invert for a fine-scale (50–100 km) three-dimensional anelastic structure.

The results shows two high-Q regions (Q_P>1000) which are consistent with the locations of the Pacific and the Philippine Sea slabs. Also there is a low-Q (Q_P110) area extending to the deeper parts (350–400 km) of the model just beneath the old spreading center and the Kinan Seamount Chain in the Shikoku Basin. A small depth dependence of the laterally averaged Q_P was found, with values of 266 (0–250 km), 301 (250–400 km), and 413 (400–500 km).  相似文献   

全站仪轴系补偿原理及检验方法探讨   总被引：1，自引：0，他引：1  

叶晓明  凌模  谢方 《测绘信息与工程》2003,28(3):40-43

全面阐述了全站仪的轴系补偿相关理论和实践，指出了我国检验规程的不足之处，提出了改进方法。  相似文献