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201.
Pasquier and Marcotte [Pasquier P, Marcotte D. Steady- and transient-state inversion in hydrogeology by successive flux estimation. Adv Wat Res 2006;29:1934–52] propose some modifications to the Comparison Model Method (CMM), in order to apply it to transient 3D ground water flow data for conductivity identification. We present some remarks on that paper to improve the comprehension of the basic features of the CMM and of the real value of the novelties introduced by Pasquier and Marcotte. 相似文献
202.
《The Photogrammetric Record》2002,17(99):505-511
18th International Symposium of Cipa by D. M. Barber, p.505
48th Photogrammetric Week by A. T. Smart, p.506
5th Conference on Optical 3D Measurement Techniques by G. Hunter, p.509 相似文献
48th Photogrammetric Week by A. T. Smart, p.506
5th Conference on Optical 3D Measurement Techniques by G. Hunter, p.509 相似文献
203.
《The Photogrammetric Record》2002,17(99):523-547
Books reviewed:
S. Openshaw and R. J. Abrahart, Geocomputation
M. Craglia and H. Onsrud, Geographic Information Research: Transatlantic Perspectives
P. J. Halls, Spatial Information and the Environment
J. Sievers and T. Schneider, Second International Symposium on Geographical Names: Geonames 2000
J. C. Leachtenauer and R. G. Driggers, Surveillance and Reconnaissance Imaging Systems: Modelling and Performance Prediction
P. A. Longley, M. F. Goodchild, D. J. Maguire and D. W. Rhind, Geographic Information Systems and Science
Y. Q. Chen and Y. C. Lee, Geographical Data Acquisition
K. Borre, Plane Networks and their Applications.
A. Hirschfield and K. Bowers, Mapping and Analysing Crime Data: Lessons from Research and Practice
O. Koelbl, Proceedings of the Oeepe Workshop on Automation in Digital Photogrammetric Production
RICS Books, Vertical Aerial Photography and Derived Digital Imagery: Client Specification Guidelines
D. E. Reeve and J. R. Petch, Gis Organisations and People: A Socio-Technical Approach 相似文献
S. Openshaw and R. J. Abrahart, Geocomputation
M. Craglia and H. Onsrud, Geographic Information Research: Transatlantic Perspectives
P. J. Halls, Spatial Information and the Environment
J. Sievers and T. Schneider, Second International Symposium on Geographical Names: Geonames 2000
J. C. Leachtenauer and R. G. Driggers, Surveillance and Reconnaissance Imaging Systems: Modelling and Performance Prediction
P. A. Longley, M. F. Goodchild, D. J. Maguire and D. W. Rhind, Geographic Information Systems and Science
Y. Q. Chen and Y. C. Lee, Geographical Data Acquisition
K. Borre, Plane Networks and their Applications.
A. Hirschfield and K. Bowers, Mapping and Analysing Crime Data: Lessons from Research and Practice
O. Koelbl, Proceedings of the Oeepe Workshop on Automation in Digital Photogrammetric Production
RICS Books, Vertical Aerial Photography and Derived Digital Imagery: Client Specification Guidelines
D. E. Reeve and J. R. Petch, Gis Organisations and People: A Socio-Technical Approach 相似文献
204.
205.
利用GPS实现大跨桥梁的实时安全监测 总被引:6,自引:0,他引:6
由于悬索桥跨度大,台风、地震、车载和温度变化对桥梁变形影响很大,对大桥实时监测,获取桥梁在上述环境下的工作状况,验证结构的抗风、抗震分析的特征参数,成为大桥安全性研究的重大课题。为连续实时监测大跨染在环境如台风、地震、车载和温度作用下的位移变形,通过比较几种桥梁传统的位移测量方法,提出利用GPS技术实时监测桥梁位移和转角的新方法,该系统能精确记录大桥的温度变化、车载、风荷载下桥梁变形的位移和模态特性,这些数据在评估大桥安全性和交通安全方面有着重要作用。 相似文献
206.
养殖珍珠微量元素特征及其对珍珠生长环境的指示意义 总被引:14,自引:0,他引:14
采用等离子光谱和X射线荧光探针等分析方法,对海水养殖珍珠和淡水养殖珍珠的微量元素特征进行了深入研究,表明:(1)海水养殖珍珠中S、Na、Mg、Sr等微量元素相对富集,Mn等相对亏损;(2)淡水养殖珍珠中Mn相对富集,而S、Na,Mg,Sr相对亏损,与海水养殖珍珠微量元素特征正好相反,研究成果对养殖珍珠的生长环境的判定及其类型的精确鉴定具有重要意义。 相似文献
207.
Considering the fact that there is only one pair of fixed potential poles in one direction used to monitor the resistivity
changes under the observatory station which may indicate process of earthquake preparation, based on the precondition that
the resistivity structure is 1-dimensional under the observatory station, and by way of equivalent model put forward by the
authors, this paper suggests a kind of method trying to separate the resistivity changes in deep layers from that of the shallow
layer. Analysis shows that, to obtain the same measured data with the same array, any a multi-layered geo-electrical structure
can be equivalently taken as a two-layered one, we call it equivalent model. In this paper, the resistivity and thickness
of the upper layer of the equivalent model are equal to that of the first layer of the original one, the resistivity of the
lower layer of the equivalent model is obtained with calculation according to the requirement of equivalence, its value is
relevant with the resistivities and thicknesses of all layer of the original model except for the first one, so the resistivity
change of the equivalent layer can indicate the synthetic effect of variation of all layers of the original model except for
the first one. The primary research results show that this method can work well.
Foundation item: Chinese Joint Seismological Science Foundation (100146). 相似文献
208.
M. I. Todorovska S. S. Ivanovi M. D. Trifunac 《Soil Dynamics and Earthquake Engineering》2001,21(3):705
For transient, high frequency, and pulse like excitation of structures in the near field of strong earthquakes, the classical design approach based on relative response spectrum and mode superposition may not be conservative. For such excitations, it is more natural to use wave propagation methods. In this paper (Part I), we review several two-dimensional wave propagation models of buildings and show results for theoretical dispersion curves computed for these models. We also estimate the parameters of these models that would correspond to a seven-story reinforced concrete building in Van Nuys, California. Ambient vibration tests data for this building imply vertical shear wave velocity βz=112 m/s and anisotropy factor βx/βz=0.55 for NS vibrations, and βz=88 m/s and βx/βz=1 for EW vibrations. The velocity of shear waves propagating through the slabs is estimated to be about 2000 m/s. In the companion paper (Part II), we estimate phase velocities of vertically and horizontally propagating waves between seven pairs of recording points in the building using recorded response to four earthquakes. 相似文献
209.
This purpose of this paper is to study the dynamic characteristics of the Fei-Tsui arch dam using the seismic response data and the ambient vibration data. For the identification of dam properties from seismic response data, the multiple inputs from the abutment of the dam to represent the nonuniform excitations of seismic input motion are considered, and the ARX model is applied using the discrete-time linear filtering approach with least-squares approximation to identify the dynamic characteristics of the dam. The system modal dampings, natural frequencies and frequency response functions are identified. A comparison of the identified modal parameters is made among different seismic events. Post-earthquake safety evaluation of the dam can be made based on the identified model. Finally, the ambient vibration test of the dam is performed to identify the mode shapes along the dam crest. 相似文献
210.
PHILIP K.HOPKE 《地理学报(英文版)》1992,(2)
In many cases,monitoring data for ambient airborne particles can be organized in the form of a three-way data table with one way for chemical species,one for sampling periods and one for sites.A directtrilinear decomposition followed by a matrix reconstruction(DTDMR)is developed to analyze such adata table as a whole.The three-way data set is composed into three two-way matrices by a direct trilineardecomposition(DTD).The column vectors of each of the matrices are called‘source profiles’,‘emissionpatterns’and‘site coefficients’respectively.Particulate sources are identified by examining both theirsource profiles and emission patterns.After the sources have been identified,emission patterns and sitecoefficients are used to produce a three-way matrix that gives estimates of mass contributions of sourcesto the samples collected at every site in every period.By simulation study,not only has the method beenverified,but a good indicator has been found that shows the number of factors(i.e.sources)in thesystem.Unlike other receptor models,DTDMR does not require source profile data and does not involvetrial-and-error procedures.Since DTDMR identifies sources based on variations in two dimensions,it hasa higher potential to distinguish two sources that have similar chemical compositions.The DTDMRmodel has provided excellent results with simulated data and has been applied in a real world three-waydata set. 相似文献