Selection of Spectral Sensitivity for Optical Systems Used in Studying the Earth from Space

1975 ◽  
Vol 116 (8) ◽  
pp. 746
Author(s):  
Yu.M. Chesnokov ◽  
V.A. Kottsov
1975 ◽  
Vol 26 ◽  
pp. 395-407
Author(s):  
S. Henriksen

The first question to be answered, in seeking coordinate systems for geodynamics, is: what is geodynamics? The answer is, of course, that geodynamics is that part of geophysics which is concerned with movements of the Earth, as opposed to geostatics which is the physics of the stationary Earth. But as far as we know, there is no stationary Earth – epur sic monere. So geodynamics is actually coextensive with geophysics, and coordinate systems suitable for the one should be suitable for the other. At the present time, there are not many coordinate systems, if any, that can be identified with a static Earth. Certainly the only coordinate of aeronomic (atmospheric) interest is the height, and this is usually either as geodynamic height or as pressure. In oceanology, the most important coordinate is depth, and this, like heights in the atmosphere, is expressed as metric depth from mean sea level, as geodynamic depth, or as pressure. Only for the earth do we find “static” systems in use, ana even here there is real question as to whether the systems are dynamic or static. So it would seem that our answer to the question, of what kind, of coordinate systems are we seeking, must be that we are looking for the same systems as are used in geophysics, and these systems are dynamic in nature already – that is, their definition involvestime.


1986 ◽  
Vol 29 (1) ◽  
pp. 53-57
Author(s):  
A. S. Koshelev ◽  
G. N. Maslov ◽  
Yu. V. Petrov

Author(s):  
Filippo Del Lucchese

This chapter examines Empedocles’s idea of monstrosity in the early generation of life, when the earth spontaneously produces all sort of monstrous beings, only some of which will survive and generate viable forms of life. Empedocles intends to establish the norms of life on the process of generation and selection of monstrosities. Nature is not an artist that shapes normal life after many unsuccessful attempts. Empedocles rather sees Nature itself as the successful result of spontaneuous events that create limits and boundaries for viable life. The other major philosopher of the pre-Platonic period is Democritus. I explore his materialism and its relationship with necessity and chance. Atomists have been accused of paradoxically grounding their universe on both necessity and chance. I show that the paradox, however, is only such from the Aristotelian perspective, which aims at establishing teleology as the highest form of causality, in particular in the biological realm. Through the idea of monstrosity, Democritus grounds its atomism on the concept of the spontaneous formation of life. Beyond Empedocles, Democritus flattens even further the material ontology of nature, grounding it on the epigenetical production of normal and mostrous life alike. Through a reading of the agonistic process of life formation, monstrosity becomes the antidote to teleology.


2020 ◽  
Vol 12 (15) ◽  
pp. 2468 ◽  
Author(s):  
Dennis Helder ◽  
Cody Anderson ◽  
Keith Beckett ◽  
Rasmus Houborg ◽  
Ignacio Zuleta ◽  
...  

One of the biggest changes in the world of optical remote sensing over the last several years is the sheer increase in the number of sensors that are imaging the Earth in moderate to high spatial resolution. With respect to the calibration of these sensors, they are broadly classified into two types, namely government systems and commercial systems. Because of the differences in the design and mission of these sensor types, calibration approaches are often substantially different. Thus, an opportunity exists to foster discussion between calibration teams for these sensors with the goal of improving overall sensor calibration and data interoperability. The approach used to accomplish this task was a one-day workshop where team members from both government and commercial sensors could share best practices, discuss methods for collaboration and improvement, and make recommendations for continuing activities. Five major recommendations were developed from the event that focused on coordinated activities using pseudo invariant calibration sites (PICS), broader and more consistent communication, collaboration on specific cross-calibration opportunities, developing a reference sensor for all optical systems, and encouraging the coordinated development of surface reflectance products. Workshop participants concluded that regular interactions between these teams could foster a better calibration of all sensor systems and accelerate the improved interoperability of surface products.


1946 ◽  
Vol 24a (4) ◽  
pp. 15-40 ◽  
Author(s):  
L. E. Howlett

The nature of photographic resolving power is discussed and attention called to the widespread misconception of it that exists at the present time. Most of the detailed discussion applies specifically to photographic objectives intended for use in aerial photography but the general approach to their photographic resolving power is applicable to studies of the photographic performance of all types of optical systems. An annulus type of target is proposed as more suitable than line targets. A method is given for the selection of the photographic focal plane when the essential requirement of the photographic use is the acquisition of maximum information. General remarks are made on the proper trend to be followed in the future design of photographic objectives. Results are presented on a study of a number of well known types of photographic objectives used for aerial photography.


Author(s):  
A. Yu. Kuznecov ◽  
A. A. Sadikova ◽  
V. I. Gornyj ◽  
I. Sh. Latypov

The aim of the work is to research and develop methods for synthesizing aperture in hyperspectral systems for remote sensing of the Earth to reduce weight and size characteristics by applying methods of program-algorithmic processing of the input signal and implementing the synthesized aperture. A method of neural networks for deconvolution on the construction of a radial basis network is developed. A method has been developed to increase the synthesis of apertures in hyperspectral systems for remote sensing of the Earth. A method for increasing the spatial resolution of images obtained by optical systems for remote sensing of the Earth is described. A method for radiometric calibration of output data has been developed, which allows universalizing the analysis of spectral characteristics. In the process, to achieve the goals were used: methods of spectral optics, mathematical analysis and statistics, methods of processing images and signals. The project results contribute to the reduction of overall weight and cost characteristics and the possibility of synthesizing the aperture at the exit of the polychromator, which will avoid the use of expensive camera lenses in hyperspectral systems of remote sensing of the Earth. The developed methods for synthesizing aperture in hyperspectral systems of remote sensing of the Earth differ from the existing ones in that the receiving device for the video signal does not contain structural changes, and they contain the function of the algorithmic apparatus, which includes the analysis of the functions of the scattering point, the deconvolution of the recorded signal is performed by the method of neural networks after the stage learning.


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