scholarly journals A Real-Time Deformation Monitoring Method for Large-Scale Structure Based on Relay Camera

2021 ◽  
Vol 2021 ◽  
pp. 1-10
Author(s):  
Chuan He ◽  
Lianxiong Liu ◽  
Changhua Hu

In the process of the deformation monitoring for large-scale structure, the mobile vision method is often used. However, most of the existent researches rarely consider the real-time property and the variation of the intrinsic parameters. This paper proposes a real-time deformation monitoring method for the large-scale structure based on a relay camera. First, we achieve the real-time pose-position relationship by using the relay camera and the coded mark points whose coordinates are known. The real-time extrinsic parameters of the measuring camera are then solved according to the constraint relationship between the relay camera and the measuring camera. Second, the real-time intrinsic parameters of the measuring camera are calculated based on the real-time constraint relationship among the extrinsic parameters, the intrinsic parameters, and the fundamental matrix. Finally, the coordinates of the noncoded measured mark points, which are affixed to the surface of the structure, are achieved. Experimental results show that the accuracy of the proposed method is higher than 1.8 mm. Besides, the proposed method also possesses the real-time and automation property.

Universe ◽  
2020 ◽  
Vol 6 (10) ◽  
pp. 168
Author(s):  
Christopher Marsden ◽  
Francesco Shankar

In this work we present “Astera’’, a cosmological visualization tool that renders a mock universe in real time using Unreal Engine 4. The large scale structure of the cosmic web is hard to visualize in two dimensions, and a 3D real time projection of this distribution allows for an unprecedented view of the large scale universe, with visually accurate galaxies placed in a dynamic 3D world. The underlying data are based on empirical relations assigned using results from N-Body dark matter simulations, and are matched to galaxies with similar morphologies and sizes, images of which are extracted from the Sloan Digital Sky Survey. Within Unreal Engine 4, galaxy images are transformed into textures and dynamic materials (with appropriate transparency) that are applied to static mesh objects with appropriate sizes and locations. To ensure excellent performance, these static meshes are “instanced’’ to utilize the full capabilities of a graphics processing unit. Additional components include a dynamic system for representing accelerated-time active galactic nuclei. The end result is a visually realistic large scale universe that can be explored by a user in real time, with accurate large scale structure. Astera is not yet ready for public release, but we are exploring options to make different versions of the code available for both research and outreach applications.


2014 ◽  
Vol 4 (1-2) ◽  
pp. 42-45 ◽  
Author(s):  
A. Tugay

Filaments are clearly visible in galaxy distributions, but they are difficult to detect by computer algorithms. Most methods of filament detection can be used only with numerical simulations of a large-scale structure. New simple and effective methods for the real filament detection should be developed. The method of a smoothed galaxy density field was applied in this work to SDSS data of galaxy positions. Five concentric radial layers of 100 Mpc are appropriate for filaments detection. Two methods were tested for the first layer and one more method is proposed.


1988 ◽  
Vol 130 ◽  
pp. 495-505
Author(s):  
P. J. E. Peebles

This conference has been marked by our willingness to entertain grand schemes of synthesis of theoretical ideas and the observational evidence on how galaxies and large-scale structure might have formed. At IAU Symposium 104 on this subject held in Crete just 5 years ago there was little discussion of how all the pieces of the puzzle might fit together. Now we have at least three candidate grand syntheses that have been worked out in some detail and have been discussed here: scale-invariant cold dark matter, by Frenk; massive cosmic strings, by Turok; and exploding magnetized superconducting cosmic strings, by Ostriker. I have accordingly placed each of the topics I want to review under the heading of the grand scheme for which it seems most embarrassing. This negative approach is a little unfair, but I think we can take it as given that we would not be considering a scheme that did not have many good points, and that the real interest is the probing of weak points by which we hope to learn which schemes might be strengthened, which might safely be abandoned.


2014 ◽  
Vol 59 (1) ◽  
pp. 79-92
Author(s):  
Alexander Becker

Wie erlebt der Hörer Jazz? Bei dieser Frage geht es unter anderem um die Art und Weise, wie Jazz die Zeit des Hörens gestaltet. Ein an klassischer Musik geschultes Ohr erwartet von musikalischer Zeitgestaltung, den zeitlichen Rahmen, der durch Anfang und Ende gesetzt ist, von innen heraus zu strukturieren und neu zu konstituieren. Doch das ist keine Erwartung, die dem Jazz gerecht wird. Im Jazz wird der Moment nicht im Hinblick auf ein Ziel gestaltet, das von einer übergeordneten Struktur bereitgestellt wird, sondern so, dass er den Bewegungsimpuls zum nächsten Moment weiterträgt. Wie wirkt sich dieses Prinzip der Zeitgestaltung auf die musikalische Form im Großen aus? Der Aufsatz untersucht diese Frage anhand von Beispielen, an denen sich der Weg der Transformation von einer klassischen zu einer dem Jazz angemessenen Form gut nachverfolgen lässt.<br><br>How do listeners experience Jazz? This is a question also about how Jazz music organizes the listening time. A classically educated listener expects a piece of music to structure, unify and thereby re-constitute the externally given time frame. Such an expectation is foreign to Jazz music which doesn’t relate the moment to a goal provided by a large scale structure. Rather, one moment is carried on to the next, preserving the stimulus potentially ad infinitum. How does such an organization of time affect the large scale form? The paper tries to answer this question by analyzing two examples which permit to trace the transformation of a classical form into a form germane to Jazz music.


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