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281.
Spatial Relation Resolution and Spatial Relation Abstraction 总被引:1,自引:0,他引:1
AlTinghua LIUYaolin 《地球空间信息科学学报》2003,6(4):10-16
This paper attempts to regard spatial relation transformation as an important process in map generalization. The spatial relation generalization can be divided into the components of abstraction: topology, distance and orientation. The concept‘‘ spatial relation resolution‘‘ is introduced to describe the constraints of relative spatial relation. On the basis of nine intersection models, the cardinal direction models and the iso-dis-tance-relation models, this paper gives three sorts of relation resolution representations for topological, distance and orientation relation, respectively. Two mapping implementations in map generalization is discussed. 相似文献
282.
The determination of the attitude, the position and the intrinsic geometric characteristics of the camera is recognised as the fundamental photogrammetric problem. It can be summarised as the determination of camera interior and exterior orientation parameters, as well as the determination of 3D coordinates of object points. The term "exterior orientation"of an image refers to its position and orientation related to an exterior (object space) coordinate system. Several methods can be applied to determine the parameters of the orientation of one, two or more photos. The orientation can be processed in steps (as relative and absolute orientation) but simultaneous methods (such as bundle adjustments) are now available in many software packages. Several methods have also been developed for the orientation of single images. They are based in general on geometric and topological characteristics of imaged objects.
This paper presents a survey of classical and modern methods for the determination of the exterior parameters in photogrammetry, some of which are available as software packages (with practical examples) on the Internet. The methods presented are classified in three principal groups. In the first, a selection of approximate methods for applications that do not require great accuracy is presented. Such methods are also used to calculate values required for iterative processes. In the second group, standard point–based methods derived from collinearity, coplanarity or coangularity conditions are briefly reviewed, followed by line–based approaches. The third group represents orientation methods based on constraints and on concepts of projective geometry, which are becoming of increasing interest for photogrammetrists. In the last section, the paper gives a summary of existing strategies for automatic exterior orientation in aerial photogrammetry. 相似文献
This paper presents a survey of classical and modern methods for the determination of the exterior parameters in photogrammetry, some of which are available as software packages (with practical examples) on the Internet. The methods presented are classified in three principal groups. In the first, a selection of approximate methods for applications that do not require great accuracy is presented. Such methods are also used to calculate values required for iterative processes. In the second group, standard point–based methods derived from collinearity, coplanarity or coangularity conditions are briefly reviewed, followed by line–based approaches. The third group represents orientation methods based on constraints and on concepts of projective geometry, which are becoming of increasing interest for photogrammetrists. In the last section, the paper gives a summary of existing strategies for automatic exterior orientation in aerial photogrammetry. 相似文献
283.
This paper aims at multiscale representation of urban GIS,presenting a model to dynamically generalize the building on the basis of Delaunay triangulation model.Considering the constraints of position accuracy,statistical area balance and orthogonal characteristics in building cluster generalization,this paper gives a progressive algorithm of building cluster aggregation,including conflict detection (where),object(who) displacement,and geometrical combination operation(how).The algorithm has been realized in an interactive generalization system and some experiment illustrations are provided. 相似文献
284.
N. V. Pravikova E. A. Matveeva Al. V. Tevelev A. B. Veimarn A. V. Rudakova 《Moscow University Geology Bulletin》2008,63(6):359-367
The paper discusses Late Devonian and Early Carboniferous volcanic rock complexes in the Southern Urals and describes relationships between them. The general trend of volcanism evolution has been revealed, and a new geodynamic model is suggested for the discussed time interval. 相似文献
285.
286.
Complex electrical resistivity and permeability were measured on two gneiss samples and nine amphibolites (originally located at a depth of 4150 m to 5012 m) from the main drilling of the German deep drilling project (KTB). Measurements were performed as a function of hydrostatic pressures up to 240 MPa on core samples (30 mm in diameter and 10–20 mm high). For each measurement, two samples were used, one being parallel, and one perpendicular to the borehole axis. At low pressures and again at maximum pressure the frequency dispersion (1 kHz up to 1 MHz) of the complex resistivity was measured using a two electrode device. An unusual pressure effect was detected on some of the samples and was established to be due to the oriented deposition of good conducting phases in the foliation. Rock fabric and the orientation of ore mineralization was measured on thin sections and polished sections prepared from the same samples. 相似文献
287.
El. Al. IVANOV 《Geostandards and Geoanalytical Research》1981,5(1):27-29
La préparation et l'étude préliminaire d'un Granite de Bulgarie (G-B), préparé en vue d'utilisation comme un échantillon géochimique de référence sont brièvement présentées. Cet échantillon est disponible en quantité importante (180 kg). 相似文献
288.
In the present work the most characteristic mechanical and physical properties of ten Hellenic marbles were investigated. The marbles, five of which were white and the other five coloured, are the most representative ones found in Greece. Among those studied are the famous marbles of Paros and Penteli, the latter being the basic material of the Parthenon. After a rough classification and the determination of their composition, the following properties of each marble were determined: specific gravity; apparent density; behaviour in water; coefficient of thermal conductivity; coefficient of linear thermal expansion and its variation with temperature; strength in various loading forms; and dynamic modulus of elasticity as well as the resistance to frost and corrosion. All the results obtained are given in diagrammatic and tabular forms. On the basis of these results, useful conclusions regarding the utility of each marble for various applications are derived. 相似文献
289.
290.
Zeid Abdullah ALOthman Mohamed Abdelaty Habila Nora H. Al-Shalan Sulaiman M. Alfadul Rahmat Ali Ibrahim Gar Al alm Rashed Bader Alfarhan 《Arabian Journal of Geosciences》2016,9(4):315
This work aimed to investigate the adsorption characteristics, both kinetically and thermodynamically, of Cu(II) and Pb(II) removal from aqueous solutions onto mixed-waste activated carbon, as well as to study the competitive behavior found in mixed heavy metal solution systems. This study shows that activated carbon prepared from mixed waste is an effective adsorbent for the removal of Cu(II) and Pb(II) from aqueous solutions, with the aim of detoxifying industrial effluents before their safe disposal onto water surfaces. The adsorption process was characterized in terms of kinetic and thermodynamic studies. In addition, the influence of presence of Cu(II) and Pb(II) in a competitive system was investigated. The results showed that the maximum adsorption capacities were gained at a pH of 6 with a contact time of 180 min, a metal solution concentration of 300 ppm, and an adsorbent dose of 0.3 g/L. The adsorption process was found to follow a pseudo-first-order kinetic model. Thermodynamic parameters such as ΔG o, ΔH o, and ΔS o showed that the sorption process was spontaneous and endothermic in nature. A competitive study demonstrated the applicability of mixed-waste activated carbon to adsorb Cu(II) and Pb(II) from a solution of mixed metals. In addition, the adsorption capacity was found to be as effective as other adsorbents reported in the literature. The developed adsorptive removal procedure was applied for treatment of real wastewater samples and showed high removal efficiency. 相似文献