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Large-scale geosimulations using GEM and trilions
Blaheta, Radim; Jakl, Ondřej; Hrtus, Rostislav; Kolcun, Alexej; Kohut, Roman; Starý, Jiří; Turan, E.
2017 - English
The project deals with efficient solution of singular symmetric positive semidefinite problems. Our motivation arises from the \nneed to solve special problems of geotechnics, e.g. to perform upscaling analysis of geocomposites. In that and other applications we have to solve boundary problems with pure Neumann boundary conditions. We show that the stabilised PCG method with various preconditioners is a good choice for systems resulting from the numerical solution of Neumann problems, or more generally problems with a known small dimensional null space. The work was also taken as an opportunity to compare parallel implementations of the orresponding solvers, namely implementations in the in-house finite element software GEM and implementations employing components of the general Trilinos library. The studies show that the solvers based on GEM are highly competitive with its recognised counterpart.
Keywords:
singular symmetric positive semidefinite problems; special problems of geotechnics; PCG method
Fulltext is available at external website.
Large-scale geosimulations using GEM and trilions
The project deals with efficient solution of singular symmetric positive semidefinite problems. Our motivation arises from the \nneed to solve special problems of geotechnics, e.g. to ...
SNA´17 - Seminar on Numerical Analysis
Blaheta, Radim; Starý, Jiří; Sysalová, Dagmar
2017 - English
Seminar on Numerical Analysis 2017 (SNA'17) is a continuation in a series of SNA events held in different places in the Czech Republic and organized alternatively by Ostrava and Prague institutions. TheSNA'17isorganizedbytheInstituteofGeonicsoftheCASincollaborationwith VŠB - Technical University of Ostrava and IT4Innovations National Supercomputing Centre. Conference location is one of the lecture rooms in New Aula of the VŠB-TU Ostrava. Let us note that SNA 2016 was reshaped to EMS School in Applied Mathematics (ESSAM) devoted to mathematical modelling, numerical analysis and scientific computing. The SNA'17 is turning back to more traditional winter event. It provides opportunity for meeting and mutual information of the community working in computational mathematics and computer science, but an important part of SNA is devoted to the Winter School with tutorial lectures focused on selected important topics within the scope of numerical methods and modelling.
Keywords:
mathematics; numerical analysis; modelling
Fulltext is available at external website.
SNA´17 - Seminar on Numerical Analysis
Seminar on Numerical Analysis 2017 (SNA'17) is a continuation in a series of SNA events held in different places in the Czech Republic and organized alternatively by Ostrava and Prague institutions. ...
Professor Ivo Marek (1933-2017)
Blaheta, Radim; Tůma, Miroslav
2017 - English
Ivo Marek, Professor at Charles University and the Czech Tec\nhnical University in Prague, was for many decades one of the best-known Czech ma\nthematicians, who contributed significantly to the development of computa\ntional methods and numerical analysis. At the same time, he was a teacher and a le\nading personality that integrated and influenced the Czech mathematical commu\nnity.
Fulltext is available at external website.
Professor Ivo Marek (1933-2017)
Ivo Marek, Professor at Charles University and the Czech Tec\nhnical University in Prague, was for many decades one of the best-known Czech ma\nthematicians, who contributed significantly to the ...
The GIS support to measures on the ground in case of leakage of liquid pollutant on the road
Kolejka, Jaromír; Rapant, P.; Zapletalová, Jana
2016 - English
Accidents on roads associated with the leakage of hazardous substances are one of the major challenges encountered by disaster management. Because of the impossibility of predicting the place and time of the event, then it is necessary in the event of such an accident to proceed in quick succession of steps. They are designed primarily to protect human life and health, and then to minimize to property and environment damage. The paper describes the response to this event using GIS tools and generally available geodata. The simulated accident on the D1 highway near Ostrava is applied as a demonstration example.
Keywords:
GIS decision support; geographic data and knowledge; geography
Available in digital repository of the ASCR
The GIS support to measures on the ground in case of leakage of liquid pollutant on the road
Accidents on roads associated with the leakage of hazardous substances are one of the major challenges encountered by disaster management. Because of the impossibility of predicting the place and time ...
Geodiversity values as a basis for geosite and geomorphosite assessment: a case study from Žďárské vrchy Highland
Bajer, A.; Kirchner, Karel; Kubalíková, L.
2016 - English
Paper presents geodiversity values, geodiversity is understood as a set of geological, geomorphological and pedological components, including systems consisting of this components and geological, geomorphological and pedological processes. Geodiversity values are analyzed in relation to ecosystem values (e.g. cultural, functional value). Geodiversity values were used as basis for a methodical approach to geosite and geomorphosite assessment. Methodological approach is presented at selected sites in the top part of the Žďárské vrchy Highland. The acquired results can serve as a basis for geoconservation of PLA Žďárské vrchy, development of geotourism as well as an offer for extension geoeducational activities.\n
Keywords:
geodiversity; geoeducation; geosite; geomorphosite assessment
Available in digital repository of the ASCR
Geodiversity values as a basis for geosite and geomorphosite assessment: a case study from Žďárské vrchy Highland
Paper presents geodiversity values, geodiversity is understood as a set of geological, geomorphological and pedological components, including systems consisting of this components and geological, ...
European countgryside and its perception
Zapletalová, Jana; Vaishar, Antonín; Šťastná, M.
2016 - English
Rural area was traditionally connected with agriculture. To compare with urban, rural areas were considered to be backward, retarded, not worthy of an intensive research. But \nthe situation has changed in the last time. Although cities are still centres of development in the globalization process, people in Europe leave them as a result of the \ntrends of suburbanization and counter - urbanization. We intend to pay our attention on transformation processes of the European countryside. We can focus on more processes occurring there: transformation from productive to non-productive, from central planned to the market oriented countryside, from the mono-functional to the multifunctional, from the national to \nEuropean and globalized. The urbanisation process shows more faces in European countryside. Such a transformation generates many impacts on natural, economic and social \nprocesses occurring in present European countryside.
Keywords:
European countryside; Europe; rural settlement; countryside
Available in digital repository of the ASCR
European countgryside and its perception
Rural area was traditionally connected with agriculture. To compare with urban, rural areas were considered to be backward, retarded, not worthy of an intensive research. But ...
Bukov PVP underground research laboratory - geotechnical conditions of construction
Souček, Kamil; Vavro, Martin; Staš, Lubomír; Koníček, Petr; Ptáček, Jiří; Waclawik, Petr; Vavro, Leona; Lednická, Markéta; Kaláb, Zdeněk; Šňupárek, Richard; Vondrovic, L.
2016 - English
Bukov PVP Underground Research Laboratory (Bukov URL) is designed to be a test site for the evaluation of properties and behavior of the rock mass which is of similar type as selected candidate sites in the Czech Republic. It is situated at a depth corresponding to the proposed storage depth of the final locality for the national deep repository of high-level radioactive waste. The Bukov URL, the construction of which has begun in 2013, is situated in the southern part of the Rožná uranium deposit, at the northeastern periphery of the Strážek Moldanubicum close to its contact with the Svratka Unit. The rock mass is composed of relatively monotonous rock sequences primarily of a volcanosedimentary origin. They are currently represented, due to the subsequent tectonometa-morphic development, by migmatized biotite paragneisses up to stromatitic and/or oftalmitic migmatites, amphibole-biotite to biotite-amphibole gneisses, and amphibolites. The workings of the Bukov URL are situated on the level 12 of the Bukov-1 shaft, at the depth of about 600 m below the earth’s surface. The Bukov URL is still under construction and the research works by the consortium of several organizations – ÚJV Řež, a.s., Czech Geological Survey, Institute of Geonics of the CAS, v.v.i., and Arcadis CZ, a.s. - are carried out simultaneously. The research activities focus on a complex geological and geotechnical characterization of the rock mass of interest, which is vital for the realization of further research in situ. This paper briefly describes the technical solution of the Bukov URL and the process of its construction.
Keywords:
Bukov URL; rock mass; radioactive waste
Available in digital repository of the ASCR
Bukov PVP underground research laboratory - geotechnical conditions of construction
Bukov PVP Underground Research Laboratory (Bukov URL) is designed to be a test site for the evaluation of properties and behavior of the rock mass which is of similar type as selected candidate sites ...
Secondary geodiversity and its potential for geoeducation and geotourism: a case study from Brno city
Kubalíková, Lucie; Bajer, A.; Kirchner, Karel
2016 - English
Geodiversity is considered to be the most important resource for geoeducational and geotourist activities. Usually the geoeducation and geotourism are developed within natural areas and they are based on the primary geodiversity (natural landforms). Nevertheless, so called secondary geodiversity or man-made/anthropogenic geodiversity (represented by the anthropogenic geosites as old quarries, pits or underground landforms) can be also viewed as a remarkable resource for these activities. Brno city is rich in these landforms; some of them already serve as excursion localities for the university students or they are used for recreation and leisure, some of them are unique (from the geoscience point of view) and they have also certain added values (historical, archaeological or ecological), however, their potential is not fully developed. The article presents examples of these geosites and outlines possibilities of the rational use for the geoeducation and geotourism purposes.
Keywords:
anthropogenic landforms; geosites; geoeducational and geotourist activities
Available in digital repository of the ASCR
Secondary geodiversity and its potential for geoeducation and geotourism: a case study from Brno city
Geodiversity is considered to be the most important resource for geoeducational and geotourist activities. Usually the geoeducation and geotourism are developed within natural areas and they are based ...
Preliminary study using pulsating water jet for bone cement demolition
Hloch, Sergej; Kloc, J.; Foldyna, Josef; Pude, F.; Smolko, I.; Zeleňák, Michal; Sitek, Libor; Hvizdoš, P.; Monka, P.; Monková, K.; Kozak, D.; Stoić, A.; Sedmak, A.; Milosevic, M.; Lehocká, D.; Mihalčinová, E.
2015 - English
The paper deals with the study of using the selective property of ultrasonic pulsating water jet for the disintegration of bone cement which creates the interface between femoral stem and trabecular bone tissue. For investigation, commercial bone cements were used. Bone cements were tested by nanoindentation in order to review their mechanical properties. A representative sample Palacos R+G was selected for disintegration of bone cement. Bone cements samples fixed between two plexiglasses were disintegrated using ultrasonic water jet and water jet generated by self-resonating nozzle at the pressure level of 20 MPa. Visualisation of bone cement demolition was provided with high speed 1 kHz cameras with two led pulsed sources. Potential were observed for using of pulsating water jet for bone cement demoliton during femoral stem extraction.
Keywords:
bone cement; ultrasonic pulsating water jet; revision arthroplasty
Available in digital repository of the ASCR
Preliminary study using pulsating water jet for bone cement demolition
The paper deals with the study of using the selective property of ultrasonic pulsating water jet for the disintegration of bone cement which creates the interface between femoral stem and trabecular ...
Study of surface topography of material eroded by pulsating water jet
Klich, Jiří; Klichová, Dagmar
2015 - English
The paper focuses on the study of the effect of technological parameters on the topography of a surface eroded by a pulsating water jet. Parameters of the water pressure and the traversing velocity of the nozzle over the surface were observed. Effects of technological parameters were compared to the surface roughness parameters Ra, Rz, Rv, Rp, Rsk and Rku. The material tested was the aluminium alloy EN AW6060 T66. The surface was measured using an optical profilometer and further assessed using the confocal microscope based on a metallographic section.
Keywords:
pulsating water jet (PWJ); surface roughness; erosion
Available in digital repository of the ASCR
Study of surface topography of material eroded by pulsating water jet
The paper focuses on the study of the effect of technological parameters on the topography of a surface eroded by a pulsating water jet. Parameters of the water pressure and the traversing velocity ...
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