scholarly journals On Cosmic Epochand Linear Size/Luminosity Evolution of Compact Steep Spectrum Sources

2021 ◽  
Vol 9 (1) ◽  
pp. 8
Author(s):  
Ezeugo Jeremiah Chukwuemerie
Author(s):  
Dmitriy B. Slinko ◽  
Vyacheslav A. Denisov ◽  
Dmitriy A. Dobrin ◽  
Andrey V. Afanas’yev ◽  
Pavel M. Kislov

Reducing operating costs during soil processing and increasing the wear resistance of parts and components is an important condition for reducing the cost of agricultural products, increasing its efficiency and competitiveness. The development of materials with increased wear resistance and new effective technologies for strengthening working bodies in their manufacture is now becoming an urgent task. (Research purpose) The research purpose is increasing the wear resistance of the working bodies of soil-processing machines by electric arc surfacing. (Materials and methods) During the experimental study, it has been performed testing of modes and surfacing of a pilot batch of working bodies from Kverneland for field tests in VIM on an automated installation for electric arc surfacing. Authors used eutectic CastolinEnDotec DO*30 powder wire with a diameter of 1.2 millimeters and a boron content of up to 4 percent for surfacing wear-resistant rollers, which allows to obtain wear-resistant rollers with a hardness of up to 65 HRC without pores and cracks. (Results and discussion) It has been revealed that hardened ploughshares that have passed field tests are subject to lower wear rates compared to non-hardened ones. It was found that when operating time is 24.785 hectares per ploughshare, the wear of the linear size of the cutting edge along the width of hardened ploughshares is on average up to 10-11 millimeters less than that of non-hardened ones. It was found that when processing 228 hectares, the wear of the linear size of the cutting edge along the width of hardened bits is on average up to 9-10 millimeters less than that of non-hardened ones. (Conclusions) The technology of surfacing with intermittent wear-resistant rollers provides an increase in the efficiency of hardening of Kverneland working bodies according to the criterion of wear resistance by an average of 20-30 percent. The adjusted technological parameters of the surfacing process will reduce the wear rate and increase the service life of the blade part of the working bodies, as well as reduce the amount of surfaced material by an average of 60 percent. The continuation of work on strengthening the working bodies should be aimed at changing the surfacing scheme and choosing a cheaper domestic cored wire.


1999 ◽  
Vol 511 (2) ◽  
pp. 574-584 ◽  
Author(s):  
Ping He ◽  
Yuan‐Zhong Zhang

2018 ◽  
Vol 1067 ◽  
pp. 022006
Author(s):  
N Karastathis ◽  
F Antoniou ◽  
I Efthymiopoulos ◽  
M Hostettler ◽  
G Iadarola ◽  
...  
Keyword(s):  

2014 ◽  
Vol 554 ◽  
pp. 50-63 ◽  
Author(s):  
Joshua Baron ◽  
Yuval Ishai ◽  
Rafail Ostrovsky

2017 ◽  
Vol 43 (8) ◽  
pp. 1421-1427
Author(s):  
M.P. Foschini ◽  
R. Miglio ◽  
C. Quinn ◽  
B. Belgio ◽  
P. Regitnig ◽  
...  

1980 ◽  
Vol 92 ◽  
pp. 269-277
Author(s):  
Gary L. Grasdalen

The (V-K) colors of giant elliptical galaxies as a function of redshift are discussed. Present data are consistent with mild color evolution at z ~ 0.45. An infrared Hubble (redshift-magnitude) diagram is given. Cosmological models with qo = 0 and no luminosity evolution are clearly excluded by the present data. A wide variety of models including those with qo = 0 are permissible if luminosity evolution is included. Instrumental and programmatic implications of these results are summarized.


1994 ◽  
Vol 1 (2) ◽  
Author(s):  
Alexander E. Andreev

The complexity of a nondeterministic function is the minimum possible complexity of its determinisation. The entropy of a nondeterministic function, F, is minus the logarithm of the ratio between the number of determinisations of F and the number of all deterministic functions.<br /> <br />We obtain an upper bound on the complexity of a nondeterministic function with restricted entropy for the worst case.<br /> <br /> These bounds have strong applications in the problem of algorithm derandomization. A lot of randomized algorithms can be converted to deterministic ones if we have an effective hitting set with certain parameters (a set is hitting for a set system if it has a nonempty intersection with any set from the system).<br /> <br />Linial, Luby, Saks and Zuckerman (1993) constructed the best effective hitting set for the system of k-value, n-dimensional rectangles. The set size is polynomial in k log n / epsilon.<br /> <br />Our bounds of nondeterministic functions complexity offer a possibility to construct an effective hitting set for this system with almost linear size in k log n / epsilon.


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