Thermal Drilling in Planetary Ices: An Analytic Solution with Application to Planetary Protection Problems of Radioisotope Power Sources

Astrobiology ◽  
2012 ◽  
Vol 12 (8) ◽  
pp. 799-802 ◽  
Author(s):  
Ralph D. Lorenz
2020 ◽  
Vol 7 (3) ◽  
pp. 11-22
Author(s):  
VALERY ANDREEV ◽  
◽  
ALEXANDER POPOV

A reduced model has been developed to describe the time evolution of a discharge in an iron core tokamak, taking into account the nonlinear behavior of the ferromagnetic during the discharge. The calculation of the discharge scenario and program regime in the tokamak is formulated as an inverse problem - the optimal control problem. The methods for solving the problem are compared and the analysis of the correctness and stability of the control problem is carried out. A model of “quasi-optimal” control is proposed, which allows one to take into account real power sources. The discharge scenarios are calculated for the T-15 tokamak with an iron core.


2014 ◽  
Vol 134 (3) ◽  
pp. 230-235
Author(s):  
Yuma Yamamoto ◽  
Kazuki Kawamura ◽  
Akihiro Ametani ◽  
Naoto Nagaoka ◽  
Yoshihiro Baba
Keyword(s):  

2019 ◽  
Vol 12 (3) ◽  
pp. 16-26
Author(s):  
Victor V. Kharitonov

Three first-year ice ridges have been examined with respect to geometry and morphology in landfast ice of Shokal'skogo Strait (Severnaya Zemlya Archipelago) in May 2018. Two of the studied ice ridges were located on the edge of the ridged field and were part of it, because their keels extended for a long distance deep into this field. Ice ridges characteristics are discussed in the paper. These studies were conducted using hot water thermal drilling with computer recording of the penetration rate. Boreholes were drilled along the cross-section of the ridge crest at 0.25 m intervals. Cross-sectional profiles of ice ridges are illustrated. The maximal sail height varied from 2.9 up to 3.2 m, the maximal keel depth varied from 8.5 up to 9.6 m. The average keel depth to sail height ratio varied from 2.8 to 3.3, and the thickness of the consolidated layer was 2.5-3.5 m. The porosity of the non-consolidated part of the keel was about 23-27%. The distributions of porosity versus depth for all ice ridges are presented.


2019 ◽  
Vol 12 ◽  
pp. 21-29
Author(s):  
Victor Ya. BESPALOV ◽  
◽  
Boris N. KARZHAVOV ◽  
Anton O. SIDOROV ◽  
◽  
...  

Author(s):  
Nikita Ravochkin

From the standpoint of historical (macro) sociology, the article examines the main directions of transformation of the sources of power identified by the English scientist M. Mann in the realities of post-modern society. The essential characteristics of the four sources of social power, which include ideology, military forces, economics and political characteristics of the organization of states, are considered. The vectors of transformations of these sources of power, contributing to changes in the image of power at the present time, are noted. The interdependence of transformations and the specificity of their manifestation at the institutional level in the political and legal sphere of public life are shown.


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