Zobrazeno 1 - 10
of 121
pro vyhledávání: '"Petkov Alexander"'
The efficiency of the working process of a forestry primer with a hydraulic drive of a rotor-thrower
Autor:
Petkov Alexander, Druchinin Denis, Popikov Petr, Pivtsov Anatoly, Zlenko Andrey, Sharov Andrey
Publikováno v:
BIO Web of Conferences, Vol 84, p 01056 (2024)
An analysis of the conducted studies of the causes of occurrence, methods and techniques used to combat and prevent a forest fire, including forest plows, ditchers and soil throwers, is presented. It has been established that units with active workin
Externí odkaz:
https://doaj.org/article/d1d7a8930ace4ae98d6d70ec0b64a0c6
Autor:
Ivanov, Stefan, Petkov, Alexander
We establish in the present paper two sub-gradient estimates for the quaternionic contact (qc) heat equation on a compact qc manifold of dimension $4n+3$, provided some positivity conditions are satisfied. These are qc versions of the prominent Li-Ya
Externí odkaz:
http://arxiv.org/abs/2405.14845
Autor:
Ivanov, Stefan, Petkov, Alexander
Curvature properties of the characteristic connection on an integrable $G_2$ space are investigated. It is proved that an integrable $G_2$ manifold has closed torsion if and only if the Ricci tensor of the characteristic connection is equal to the co
Externí odkaz:
http://arxiv.org/abs/2307.06438
Publikováno v:
EPJ Web of Conferences, Vol 176, p 05020 (2018)
A modified data-processing technique of the signals recorded by zenith-directed lidar, which operates in smoke-polluted atmosphere, is discussed. The technique is based on simple transformations of the lidar backscatter signal and the determination o
Externí odkaz:
https://doaj.org/article/003f5f8445a844ce880aac079fcb9010
Autor:
Ivanov, Stefan, Petkov, Alexander
We establish quaternionic contact (qc) versions of the so called Almost Schur Lemma, which give estimations of the qc scalar curvature on a compact qc manifold to be a constant in terms of the norm of the $[-1]$-component and the norm of the trace-fr
Externí odkaz:
http://arxiv.org/abs/2204.04482
Autor:
Ivanov, Stefan, Petkov, Alexander
We establish a new version of the CR almost Schur Lemma which gives an estimation of the pseudohermitian scalar curvature on a compact strictly pseudoconvex pseudohermitian manifold to be a constant in terms of the norm of the traceless Webster Ricci
Externí odkaz:
http://arxiv.org/abs/2204.03461
Publikováno v:
EPJ Web of Conferences, Vol 119, p 25001 (2016)
The significant issue of the classic multiangle data-processing technique is that the upper boundary height, up to which the multiangle data processing technique allows reliable extraction of optical parameters of the searched atmosphere, is always s
Externí odkaz:
https://doaj.org/article/36bfa8fd2eee4b0fa97171edc6afd161
Autor:
Ivanov, Stefan, Petkov, Alexander
It is shown that the qc Yamabe problem has a solution on any compact qc manifold which is non-locally qc equivalent to the standard 3-Sasakian sphere. Namely, it is proved that on a compact non-locally spherical qc manifold there exists a qc conforma
Externí odkaz:
http://arxiv.org/abs/1612.02406
Autor:
Ivanov, Stefan, Petkov, Alexander
A quaternionic contact (qc) heat equation and the corresponding qc energy functional are introduced. It is shown that the qc energy functional is monotone non-increasing along the qc heat equation on a compact qc manifold provided certain positivity
Externí odkaz:
http://arxiv.org/abs/1608.00460
Autor:
Petkov, Alexander1 (AUTHOR), Mishra, Abhishek1 (AUTHOR), Cattelan, Mattia2,3 (AUTHOR), Field, Daniel1 (AUTHOR), Pomeroy, James1 (AUTHOR), Kuball, Martin1 (AUTHOR) martin.kuball@bristol.ac.uk
Publikováno v:
Scientific Reports. 3/1/2023, Vol. 13 Issue 1, p1-7. 7p.