scholarly journals Wave-optical treatment of the shadow cast by a large gravitating sphere

2018 ◽  
Vol 98 (10) ◽  
Author(s):  
Slava G. Turyshev ◽  
Viktor T. Toth
Keyword(s):  
Optical Treatment ◽  
Shadow Cast

scholarly journals Wave-optical treatment of the shadow cast by a large sphere

2018 ◽  
Vol 97 (3) ◽  
Author(s):  
Slava G. Turyshev ◽  
Viktor T. Toth
Keyword(s):  
Large Sphere ◽  
Optical Treatment ◽  
Shadow Cast

The Theoretical Contrast in Scanning and Conventional High Resolution Microscopes

1969 ◽  
Vol 27 ◽  
pp. 170-171
Author(s):  
E. Zeitler ◽  
M. G. R. Thomson
Keyword(s):  
Small Volume ◽  
Volume Element ◽  
Optical Processing ◽  
Image Construction ◽  
Object Interaction ◽  
Transmission Electron ◽  
Scanning Transmission ◽  
Optical Treatment ◽  
Electron Microscopes ◽  
Intensity Contrast

In the formation of an image each small volume element of the object is correlated to an areal element in the image. The structure or detail of the object is represented by changes in intensity from element to element, and this variation of intensity (contrast) is determined by the interaction of the electrons with the specimen, and by the optical processing of the information-carrying electrons. Both conventional and scanning transmission electron microscopes form images which may be considered in this way, but the mechanism of image construction is very different in the two cases. Although the electron-object interaction is the same, the optical treatment differs.

Chromatic aberration and low-voltage SEM

1987 ◽  
Vol 45 ◽  
pp. 546-547
Author(s):  
Zhifeng Shao ◽  
A.V. Crewe
Keyword(s):  
Electron Energy ◽  
Low Voltage ◽  
Spherical Aberration ◽  
Chromatic Aberration ◽  
Primary Electron ◽  
Probe Size ◽  
Non Local ◽  
Optical Treatment ◽  
Electron Microscopes ◽  
Scanning Electron Microscopes

For scanning electron microscopes, it is plausible that by lowering the primary electron energy, one can decrease the volume of interaction and improve resolution. As shown by Crewe /1/, at V0 =5kV a 10Å resolution (including non-local effects) is possible. To achieve this, we would need a probe size about 5Å. However, at low voltages, the chromatic aberration becomes the major concern even for field emission sources. In this case, δV/V = 0.1 V/5kV = 2x10-5. As a rough estimate, it has been shown that /2/ the chromatic aberration δC should be less than ⅓ of δ0 the probe size determined by diffraction and spherical aberration in order to neglect its effect. But this did not take into account the distribution of electron energy. We will show that by using a wave optical treatment, the tolerance on the chromatic aberration is much larger than we expected.

BICOLOR OPTICAL TREATMENT OF MULTI-LAYERS FILM SAMPLES

2010 ◽  
Vol 24 (08) ◽  
pp. 937-942 ◽  
Author(s):  
K. OZGA ◽  
J. EBOTHÉ ◽  
H. NGUYEN CONG ◽  
D. MARTEL ◽  
W. GRUHN ◽  
...  
Keyword(s):  
Electric Field ◽  
Power Density ◽  
Local Heating ◽  
Independent Measurement ◽  
Yag Lasers ◽  
Optical Susceptibility ◽  
Dc Electric Field ◽  
Optical Treatment ◽  
532 Nm ◽  
Multi Layer Film

In the present paper, we study the influence of simultaneous polarized optical treatment (10 ns Nd: YAG lasers with wavelengths 1064 nm and 532 nm with power density 0.6 GW/cm2) together with electrostatic dc electric field (up to 8 kV/cm) on self-assembled multi-layer film samples. The second-order optical susceptibility (SOS) achieves the maximal values after one minute simultaneous dc electrical-optical treatment. Further treatment will not enhance the values and even leads to the decrease of SOS. The independent measurement of the local temperature shows that local heating does not exceed 10.1 K.

scholarly journals Shadow cast and deflection angle of Kerr-Newman-Kasuya spacetime

2018 ◽  
Vol 2018 (10) ◽  
pp. 041-041 ◽  
Author(s):  
Ali Övgün ◽  
İzzet Sakallı ◽  
Joel Saavedra
Keyword(s):  
Deflection Angle ◽  
Shadow Cast

Exiled from History: Africa in Hegel’s Academic Practice

2018 ◽  
Vol 46 ◽  
pp. 165-194
Author(s):  
Tom C. McCaskie
Keyword(s):  
Nineteenth Century ◽  
African Studies ◽  
Academic Practice ◽  
The Past ◽  
Shadow Cast ◽  
To Come ◽  
African Intellectuals ◽  
Educational Formation

Abstract:Many scholars, African and otherwise, have excoriated G.W.F. Hegel for his dismissal of Africa from history and progress in his lectures on the philosophies of history and religion. This has been done by quoting his texts and setting his words in the context of his influence on nineteenth-century European imperialism and racism. A different approach informs this paper. I treat Hegel, a complicated person, as a working university academic with a career to make and an overriding desire to publicize his own thought. I provide biographical insights relevant to these matters, and go on to examine specific texts about Africa that Hegel either sought out or chanced upon, read, misread, excerpted, used, and misused in support of his theorizing and apriorism. Attention is paid throughout to the construction, recording, and dissemination of Hegel’s lectures, and to aspects of their reception and authority in the educational formation of selected modern African intellectuals. I argue that such persons and African studies more widely are still trying to come to grips with the long and enduring shadow cast by Hegel over both the past and present of the continent.

scholarly journals Foreword to the small wild cats special issue

2019 ◽  
Vol 11 (4) ◽  
pp. 13419-13420
Author(s):  
Angie Appel ◽  
Shomita Mukherjee
Keyword(s):  
Camera Trap ◽  
Special Issue ◽  
Catch Data ◽  
International Funding ◽  
Ecological Roles ◽  
Shadow Cast ◽  
By Catch ◽  
Wild Cats

Small wild cats are fascinating but elusive.  Biologists are only beginning to fathom their vital ecological roles in maintaining and preserving biodiversity.  Yet, surveys and conservation efforts targeting them are still underfunded.  Most of them live in the long shadow cast by the more widely known Panthera cats that attract the lion’s share of international funding.  Much of what we know about small wild cats is a result of by-catch data from camera trap surveys targeted at larger mammals.  There is still a dearth of people with passion for and expertise in research and conservation of small wild cats.  With this issue, we hope to raise your awareness for their conservation needs and inspire you to join us in unravelling their mysteries.

scholarly journals Obstacle Detection in Cluttered Traffic Environment Based on Candidate Generation and Classification

2006 ◽  
Vol 1 (4) ◽  
pp. 93 ◽  
Author(s):  
Qing Li ◽  
F.C. Sun
Keyword(s):  
Vehicle Detection ◽  
Obstacle Detection ◽  
Experimental Results ◽  
Geometrical Features ◽  
Traffic Environment ◽  
Novel Method ◽  
Shadow Cast

A novel method to detect vehicles is presented in the paper. Assumption of the vehicle is made using the geometrical features of the vehicle rear by the statistical histogram. Then hypothesis is verified using the property of the shadow cast by the car according to a prior acknowledgement of traffic scene. Finally, the vehicle detection is realized by hypothesis and verification of objects. The experimental results show the efficiency and feasibility of the method.

DFT study of elastic, half-metallic and optical properties of Co2V(Al, Ge, Ga and Si) compounds

2017 ◽  
Vol 31 (14) ◽  
pp. 1750109 ◽  
Author(s):  
Heidar Khosravi ◽  
Arash Boochani ◽  
Golnaz Rasolian ◽  
Shahram Solaymani ◽  
Sirvan Naderi
Keyword(s):  
Optical Properties ◽  
Density Functional ◽  
Magnetic Moments ◽  
Elastic Stability ◽  
Metallic Behavior ◽  
Functional Theory ◽  
Spin Mode ◽  
Half Metallic ◽  
Lattice Constants ◽  
Optical Treatment

First-principles study of elastic, electronic and optical properties of full-Heusler Co2V(Al, Ge, Ga and Si) compounds are calculated through density functional theory (DFT) to obtain and compare the mentioned properties. Equilibrium lattice constants of these compounds are in good agreement with other works. Electronic calculations are shown full spin polarization at Fermi level for all compounds, so in the down spin, indirect bandgap is calculated as 0.33, 0.6, 0.2 and 0.8 eV for Co2V(Al, Ge, Ga and Si), respectively. The integer amounts of the magnetic moments are compatible with Slater–Pauling role. The optical treatment of Co2VGa is different from three other compounds. All mentioned compounds have metallic behavior by 22 eV plasmonic frequency. The imaginary part of the dielectric function for the up spin indicates that the main optical transitions occurred in this spin mode. Moreover, the elastic results show that the Co2VGa does not have elastic stability, but the other three compounds have fully elastic stability and the Co2V(Al, Ge and Si) belong to the hardness of materials.

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