scholarly journals Close-range geological photogrammetry studies: field and laboratory procedures with examples from prograde granulite facies orthogneisses, Kerala, South India

1992 ◽  
Vol 156 ◽  
pp. 53-62
Author(s):  
A.A Garde
Keyword(s):  
South India ◽  
Granulite Facies ◽  
Ground Control ◽  
Practical Procedure ◽  
Small Frame ◽  
Palghat Gap ◽  
Close Range ◽  
On Line ◽  
Laboratory Procedures ◽  
Metamorphic Facies

Precambrian orthogneisses exposed in quarries in the Palghat Gap, KeraIa, South India, were photographed for use in geological photogrammetry studies with a 35 mm (small frame) hand-held camera. Local ground control was provided by simple means: hand level, geological compass and 2 m rule. The practical procedure of photography and acquisition of ground control data is described. The stereoscopic photographs, which show complicated field relations in gneisses with prograde, transitional amphibolite to granulite metamorphic facies relations, were studied using multi-model photogrammetry (see Dueholm, 1992) and an analytical plotter. The estimated standard deviations in the stereo models of scale, azimuth and levelling were ± 2%, 2° and 5°, respectively, but the precision was very good (Iess than 1 cm). Outcrop maps were drawn with an on-line plotter at scales varying from 1:25 to 1:200 with contour intervals between 5 and 100 cm. The plot data were transferred, edited on a Macintosh computer and made ready for publication with a vector-based graphics application.

On-Line Industrial 3D Measurement Techniques for Large Volume Objects

2005 ◽  
Vol 295-296 ◽  
pp. 423-430 ◽  
Author(s):  
Ji Gui Zhu ◽  
S.H. Ye ◽  
Xue You Yang ◽  
Xing Hua Qu ◽  
C.J. Liu ◽  
...  
Keyword(s):  
Large Volume ◽  
Measurement Techniques ◽  
Integrated System ◽  
3D Measurement ◽  
Digital Cameras ◽  
Combined Use ◽  
Small Set ◽  
Close Range ◽  
On Line ◽  
Set Up

Rapid progress in modern manufacturing demands for better measurement technique with on-line characteristics. This paper presents a systematic visual solution for on-line industrial 3D measurement. The solution comprises two parts, a multi-sensor visual inspecting station (MSVIS) and a digital close-range visual inspecting station (DCVIS). MSVIS is an integrated system with many sensors. It can meet the requirement of application with sparse measuring points distributed within a large volume. DCVIS only contains two digital cameras with one or more projectors. It has high relative accuracy and a small set up volume and is suitable for applications with dense measuring points. The combined use of MSVIS and DCVIS can provide a general solution for on-line industrial 3D measurement.

Progressive Metamorphism of Mafic Rocks from Greenschist to Granulite Facies in the Dharwar Craton of South India

1986 ◽  
Vol 94 (2) ◽  
pp. 261-282 ◽  
Author(s):  
P. Raase ◽  
M. Raith ◽  
D. Ackermand ◽  
R. K. Lal
Keyword(s):  
South India ◽  
Granulite Facies ◽  
Dharwar Craton ◽  
Mafic Rocks

A greenstone belt—basement relationship in the Tanganyika shield

1976 ◽  
Vol 113 (1) ◽  
pp. 53-60 ◽  
Author(s):  
I. S. Haidutov
Keyword(s):  
Greenstone Belt ◽  
Granulite Facies ◽  
Structural Setting ◽  
Tectonic Events ◽  
Younger Age ◽  
Metamorphic Facies

SummaryAn Archaean greenstone belt, occupied by rocks of the Nyanzian System, rests apparently unconformably on a basement composed of the metamorphites of the Dodoman System in the central part of the Tanganyika shield. The latter were originally metamorphosed in granulite facies. Two episodes of migmatization were imposed on this earlier crust producing two complexes of anatectic granitoids (Puma and Ikungi) which locally have a charnockitic character. Differences in structural setting suggest that they were developed in connection with two major tectonic events. A basin-like structure was built up during the second – Ikungi – in which the Nyanzian System occurs. The Nyanzian rocks are not migmatized and their juxtaposition with the migmatites suggests that they are of younger age. Another tectonism took place after deposition of the greenstones as a result of which they were intensely deformed. Two types of intrusive granites were emplaced in the greenschists upgrading them to hornfelses during this tectonism. An interesting feature is the coincidence of the general tectonic axes of these three events. For the successively established metamorphic processes in this Archaean nucleus a gradual downgrading of metamorphic facies is characteristic, showing its irreversible development.

Les problemes geologiques et miniers dans l'exploitation du mica phlogopite a Madagascar

1956 ◽  
Vol S6-VI (1-3) ◽  
pp. 269-273
Author(s):  
Pierre Brenon
Keyword(s):  
Granulite Facies ◽  
Fracture Pattern ◽  
Exploration And Exploitation ◽  
Basement Complex ◽  
Different Types ◽  
Metamorphic Facies

Abstract The phlogopite-bearing pyroxenites of Madagascar occur as interstratified lenses, transverse veins, and rare vertical columns in crystalline schists of the basement complex. They belong to the most highly metamorphic facies (the so-called granulite facies). The mica is concentrated along structural lines in the schists or, as in the case of the transverse veins, along an ancient fracture pattern. The latter are generally more important from an economic viewpoint. Exploration and exploitation of the mica would benefit greatly from an understanding of the different types of mineralization. If the parametamorphic nature of the diopside pyroxenites of southern Madagascar is proved, a new theory of mica mineralization must be formulated.

Automated Image Processing for on-Line Photogrammetry

2011 ◽  
Vol 130-134 ◽  
pp. 3577-3580
Author(s):  
Jun Wang ◽  
Ming Li Dong
Keyword(s):  
Image Processing ◽  
High Accuracy ◽  
Process Time ◽  
Pixel Size ◽  
Dynamic Adjustment ◽  
Close Range Photogrammetry ◽  
Close Range ◽  
On Line ◽  
Line Photogrammetry ◽  
Automated Image Processing

In order to monitor the deformation of the surface or dynamic adjustment and measurement, the real-time and on-line close range photogrammetry system is needed. Before camera calibration and 3D reconstruction, the targets in the images must be recognized and located automatically with high accuracy and speed firstly. This paper describes the automated image processing for the on-line photogrammetry system. Experimental results show that compared with the other measurement system, the accuracy of subpixel target centroid can reach to about 2% of the pixel size, while the process time of an image with 3008×2000 pixels is about 0.1S.

scholarly journals Learning the psychology of the tip-of-the-tongue phenomenon through on-line practice

Open Praxis ◽  
2017 ◽  
Vol 9 (4) ◽  
pp. 421
Author(s):  
Marcos Ruiz ◽  
María José Contreras
Keyword(s):  
Distance Education ◽  
Item Type ◽  
Laboratory Procedure ◽  
Significant Group ◽  
Distance Education Program ◽  
Psychological Phenomena ◽  
On Line ◽  
Type Interaction ◽  
Laboratory Procedures ◽  
Tip Of The Tongue

Psychology undergraduates can benefit from direct experiences with laboratory procedures of psychological phenomena. However, they are not always available for students within a distance education program. The present study included students from the Spanish National Distance Education University (UNED) that were to take part in a Basic Psychology examination session. They participated in web-sessions on a tip-of-the-tongue (TOT) laboratory procedure. The aim was to study whether their performance at TOT-related items would be differentially improved. Our results support the conclusion that practicing with the TOT application was effective in improving the TOT comprehension among students. Study A showed that the performance level was higher for the TOT-practiced participants relative to the non-practiced ones. Study B showed significant group by item-type interaction. Also, there was a significant effect of group, and item-type. The results are contextualized in the psychological institutions’ mainstream effort for Psychology to be viewed as a STEM discipline by students, the political representatives, and the society.

Two Vanishing Points Error Estimation Based on Line Clustering and Condition Adjustment with Parameters

2010 ◽  
Vol 439-440 ◽  
pp. 1197-1202 ◽  
Author(s):  
Chang Li ◽  
Ling Yang ◽  
Min Hu ◽  
Peng Cheng Liu
Keyword(s):  
Error Estimation ◽  
Vanishing Point ◽  
Vanishing Points ◽  
New Methods ◽  
Vanishing Point Detection ◽  
Close Range ◽  
On Line ◽  
Condition Adjustment ◽  
Random Sample Consensus ◽  
Point Detection

In close-range digital photogrammetry and computer vision, a major challenge is the automation of 3D reconstruction from 2D-images. And single image calibration is a fundamental task in these areas for research. It is known that camera parameters can be recovered by the vanishing points of three orthogonal directions. However, three reliable and well-distributed vanishing points are not always available. Therefore, how to estimate the error of two vanishing points is very significant for us to analyze the precision of camera calibration. New methods for vanishing point detection and error estimation are presented, which can be illustrated as follows. Firstly, the line clustering, which parallel to object lines and correspond to the vanishing points, are detected based on RANSAC (Random Sample Consensus). Secondly, "condition adjustment with parameters" is utilized to estimate a nonlinear error equation. Thirdly, the error of vanishing point is expressed by error ellipse that is derived by co-factor matrix according to adjustment principle. Finally, experimental results of vanishing points coordinates and their errors are shown and analyzed.

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