No (1149)
Number of found documents:
1149
Published from
to
Deformometrická a nivelační měření v katastrálním území obce Dětmarovice v roce 2017
Kajzar, Vlastimil; Staš, Lubomír
2017 - Czech
Ústav geoniky AV ČR, v.v.i. v Ostravě byl v souvislosti s uvažovaným hlubinným dobýváním uhelných zásob a jeho možného vlivu na katastrální území Dětmarovice požádán v roce 2001 Dolem ČSA o posouzení případných vlivů poddolování na stabilitu svahů na vybrané části katastrálního území Dětmarovice. Důsledkem dobývání jsou, mimo jiné, i poklesy povrchu, což vzhledem ke stávající morfologii terénu v předmětném katastrálním území vyvolalo obavu, zda tyto poklesy nebudou dále indukovat svahové pohyby. Institute of Geonics AS CR, v.v.i. in 2001, in connection with the underground mining of coal reserves and its possible influence on the cadastral area of Dětmarovice, Ostrava was asked in 2001 to assess the possible impacts of undermining on the stability of slopes on selected parts of the cadastral territory of Dětmarovice. Consequences of the mining are, among other things, surface drops, which, due to the existing morphology of the terrain in the cadastral area in question, raised the concern that these declines would not further induce sloping movements.
Keywords:
deformometric measuring; leveling measuring; Dětmarovice
Available at various institutes of the ASCR
Deformometrická a nivelační měření v katastrálním území obce Dětmarovice v roce 2017
Ústav geoniky AV ČR, v.v.i. v Ostravě byl v souvislosti s uvažovaným hlubinným dobýváním uhelných zásob a jeho možného vlivu na katastrální území Dětmarovice požádán v roce 2001 Dolem ČSA o posouzení ...
CFD simulation of a free surface jet of high pressure nozzle. Jet sloping 90° 85° and 75°
Říha, Zdeněk
2017 - English
The report contains CFD results and description of the two phase flow water and air. Water comes into the computational domain through the nozzle which creates water jet. The jet falls on the wall surface where flows along the surface plate in all directions (x,y mainly). The aim of the work is to show how the falling water flows on the wall surface with help of advanced CFD model. Three cases had been solved there with a various jets sloping to the bottom surface plate. The first case contains results with configuration of the geometry for the jet sloping 90o. Second case contains results with configuration of the geometry for the jet sloping 85o and third case contains results with configuration of the geometry for the jet sloping 75o, see enclosures 1, 2 and 3. Given calculation had been done as steady state calculations.
Keywords:
CDF model; free surface jet; high pressure nozzle
Available at various institutes of the ASCR
CFD simulation of a free surface jet of high pressure nozzle. Jet sloping 90° 85° and 75°
The report contains CFD results and description of the two phase flow water and air. Water comes into the computational domain through the nozzle which creates water jet. The jet falls on the wall ...
Applications of Mathematics. Special Issue - SNA ´17
Rozložník, Miroslav; Sysala, Stanislav
2017 - English
This isssue of Applications of Mathematics is devoted to the Seminar on Numerical Analysis 2017 (SNA’17) held in New Aula of the VŠB—Technical University of Ostrava, January 30–February 3, 2017, and organized by the Institute of Geonics of the Czech Academy of Sciences in collaboration with IT4Innovations National Supercomputing Centre. The history of Seminar on Numerical Analysis (SNA) goes back to 2003. In 2005–2015, SNA was organized annually by the Institute of Geonics and Institute of Computer Science of the Czech Academy of Sciences in cooperation with Charles University in Prague, Czech Technical University, and VŠB—Technical University\nof Ostrava. Since 2016, Seminar on Numerical Analysis is organized alternatively on a biannual basis with the EMS School in Applied Mathematics (ESSAM). The scope of the seminar ranges from mathematical modeling and simulation of challenging engineering problems, to methods of numerical mathematics, numerical linear algebra, and high performance computing. An important part of SNA has\nbeen devoted to its Winter School with several longer lectures or tutorials focused on selected topics within the scope of the meeting. This year part of the Winter School was also the course Parallel Linear Algebra organized within the French PRACE Advanced Training Centre Maison de la Simulation. SNA’17 was attended by 77 participants, who presented six invited Winter School lectures, 24 short communications, and several posters.
Keywords:
aplied mathematics; numerical analysis; mathematical modeling
Available at various institutes of the ASCR
Applications of Mathematics. Special Issue - SNA ´17
This isssue of Applications of Mathematics is devoted to the Seminar on Numerical Analysis 2017 (SNA’17) held in New Aula of the VŠB—Technical University of Ostrava, January 30–February 3, 2017, and ...
Předindustriální a postindustriální krajina na Moravě: koncepce a realita
Kolejka, Jaromír; Batelková, Kateřina
2017 - Czech
Přípěvek pojednává odborný obsah pojmů postindustriální a předindustriální krajina a přehled datových zdrojů potřebných k jejich zjišťování na území České republiky. V přehledu je uveden současný stav poznání a výzkumu obou typů historických krajin. Ve stručnosti je uvedena metodika jejich zjišťování, mapování a klasifikace podle klíčových vlastností. Na příkladech z historického území Moravy jsou prezentovány ukázky postindustriální krajiny Rosicko-Oslavansko a předindustriální krajiny Bělečsko. Zdůrazněn je jejich význam pro poznávací, vzdělávací a ochranářskou praxi. The paper deals with the scientific concept of the terms the post-industrial and the pre-industrial landscape and presents available data sources needed for their identification in the Czech Republic. The overview shows the current state of knowledge and the research progress in the study of such historical landscapes. In brief, the methodology of their identification, mapping and classification is given. The post-industrial landscape Rosice-Oslavany and the pre-industrial landscape Bělečsko are presented as examples from the historical territory of Moravia. Their significance for cognitive, educational and conservation practices is emphasized.
Keywords:
survey; assessment; classification; data sources; old maps; ortophoto
Available at various institutes of the ASCR
Předindustriální a postindustriální krajina na Moravě: koncepce a realita
Přípěvek pojednává odborný obsah pojmů postindustriální a předindustriální krajina a přehled datových zdrojů potřebných k jejich zjišťování na území České republiky. V přehledu je uveden současný stav ...
Ověřování skutečného napěťového pole horninového masivu za účelem zvýšení bezpečnosti v prostředí anomálních napěťových stavů
Koníček, Petr; Staš, Lubomír; Ptáček, Jiří; Kaláb, Tomáš; Chura, Jan; Souček, Kamil; Waclawik, Petr
2017 - Czech
Napěťová pole jsou jedním ze základních faktorů, které rozhodným způsobem, spolu s mechanickými a přetvárnými vlastnostmi hornin, výrazně ovlivňují chování horského masivu. Poznání napěťových polí je přínosem pro projektování a zdárnou realizaci geotechnických podzemních projektů (např. pro posouzení stability podzemních prostor, chování navržených výztuží podzemních objektů, pro časoprostorové situování podzemních objektů) zvláště v netriviálních geomechanických podmínkách jak z hlediska přírodních faktorů ovlivňujících napěťová pole (např. strukturní a geologická stavba horninového masivu, tektonická napětí, trhliny a diskontinuity v horninovém masivu), tak rovněž z hlediska antropogenních faktorů (geomechanická konfigurace podzemních prostor a dynamika jejich změn). V geotechnické praxi v našich (ČR) podmínkách bývají většinou využívány jen výpočty napěťového pole vycházející především z teoretického chování hornin a předpokládaného svislého geostatického tlaku v dané hloubce. Vývoj případných postupujících deformací napěťového pole je pak odvozován od vývoje antropogenních zásahů do relativně homogenního masivu. Ve skutečnosti je však napětí ovlivňováno i blízkými geologickými strukturami. Data získaná z výzkumu velikosti, směrů a změn napětí v horském masivu jsou zásadním přínosem v oblasti matematického modelování, kde mohou být použita jako vstupní parametry, pro získání přesnějšího obrazu o chování horského masivu a podzemních objektů v předmětných oblastech. Voltage fields are one of the key factors that, decisively, along with the mechanical and remodeling properties of rocks, greatly influence the behavior of the mountain massif. Knowledge of stress fields is beneficial for the design and successful implementation of geotechnical underground projects (eg for the assessment of the stability of underground spaces, the behavior of proposed reinforcements of underground structures, for space-time placement of underground structures) especially in non-trivial geomechanical conditions, both in terms of natural factors affecting stress fields structural and geological structure of the rock mass, tectonic stress, cracks and discontinuity in the rock mass) as well as anthropogenic factors (geomechanical configuration of the underground spaces and dynamics of their changes). Geotechnical practice in our (Czech) conditions is usually used only calculations of a voltage field based primarily on the theoretical behavior of the rocks and the assumed vertical geostatic pressure at a given depth. The development of possible progressive deformations of the stress field is then derived from the development of anthropogenic interventions into a relatively homogeneous massif. In fact, tension is also affected by close geological structures. The data obtained from the study of the magnitude, direction and change of stress in the mountain massif are a significant contribution in mathematical modeling where they can be used as input parameters to obtain a more accurate picture of the behavior of mountain massifs and underground structures in the subject areas.
Keywords:
rock mass; field voltage; stress states
Available on request at various institutes of the ASCR
Ověřování skutečného napěťového pole horninového masivu za účelem zvýšení bezpečnosti v prostředí anomálních napěťových stavů
Napěťová pole jsou jedním ze základních faktorů, které rozhodným způsobem, spolu s mechanickými a přetvárnými vlastnostmi hornin, výrazně ovlivňují chování horského masivu. Poznání napěťových polí je ...
Abrasive water jet drilling of cooling holes in aeroengines: preliminary experimental study
Hlaváček, Petr; Zlámal, T.; Sitek, Libor; Georgiovská, Lucie
2017 - English
This paper addresses an experimental investigation on the feasibility of using\nabrasive water jet (AWJ) for the drilling of small-diameter holes in aeroengines\ncomponents. These components are sprayed with ceramic thermal barrier coating\n(TBC). The required holes are typically 0.5 to 1 mm in diameter with a drilling\nangle of 30 to 90 deg. The parameters of the AWJ were varied to study their effects\non both quantitative and qualitative hole drilling parameters.
Keywords:
abrasive water jet; drilling; thermal barrier coating
Available on request at various institutes of the ASCR
Abrasive water jet drilling of cooling holes in aeroengines: preliminary experimental study
This paper addresses an experimental investigation on the feasibility of using\nabrasive water jet (AWJ) for the drilling of small-diameter holes in aeroengines\ncomponents. These components are ...
Evaluation of quality of cut surfaces created by abrasive water jet according to swiss standard SN 214001
Klichová, Dagmar; Gurková, Lucie
2017 - English
The article focuses on the evaluation of the quality of cut surfaces created by\nan abrasive water jet (AWJ) according to the Swiss standard SN 214001 (2010).\nThe standard presents a quantified description of the texture of the cut. It defines\nnew parameters and methods of parameter measurements used in order to\ncategorize the cut surface in various quality levels Q. They are so far the most\ncommonly applied form of the qualitative description of the quality of the cut\nsurfaces created by the AWJ technology.
Keywords:
surface quality; abrasive water jet; standard parameters
Available on request at various institutes of the ASCR
Evaluation of quality of cut surfaces created by abrasive water jet according to swiss standard SN 214001
The article focuses on the evaluation of the quality of cut surfaces created by\nan abrasive water jet (AWJ) according to the Swiss standard SN 214001 (2010).\nThe standard presents a quantified ...
Erosion capability of ultra-high-speed continuous waterjet and pulsating waterjet: the comparison
Sitek, Libor; Hlaváček, Petr; Klichová, Dagmar; Trieb, F.; Pude, F.
2017 - English
Advantages and possibilities of continuous ultra-high-speed waterjets (with\npressures of 600 MPa and more) when cutting metals are well known to\nthe professional public both from scientific studies and from practice. In addition\nto efficiency increased as water pressure increases and reduced water\nconsumption, abrasive consumption can also be reduced in the case of abrasive\nwaterjet. Ultra-high-speed waterjet technology allows not only to cut metal sheets\nwith pure water, but also allows cutting of harder materials such as ceramics.\nDespite the initial suspicion and technical problems associated with the reliability\nand sealing of some hyperpressure elements, high-pressure devices generating\nwater pressures around 600 MPa are now commercially available. However, no\ncomparison has been made so far concerning the efficiency of these jets with\nacoustically modulated high-speed pulsating waterjets using relatively low\npressures and higher water flow rates when eroding metallic materials.\nThe article compares cuts made by pure ultra-high-speed waterjet generated at\nhyperpressures (from 500 to 800 MPa) with erosive capabilities of pulsating\nwaterjets generated on the contrary at water pressures in the order of tens of MPa\non three metallic materials (stainless steel, mild steel and copper) using the same\njet hydraulic power.
Keywords:
hyperpressure; hydraulic power; ultra-high-speed waterjet; pulsating waterjet
Available on request at various institutes of the ASCR
Erosion capability of ultra-high-speed continuous waterjet and pulsating waterjet: the comparison
Advantages and possibilities of continuous ultra-high-speed waterjets (with\npressures of 600 MPa and more) when cutting metals are well known to\nthe professional public both from scientific studies ...
Velocity measurements on continuous micro water jet using fluorescent PMMA seeding particles
Zeleňák, Michal; Ščučka, Jiří; Souček, Kamil
2017 - English
The paper deals with application of optical diagnostic techniques for velocity\nmeasurements of continuous micro water jet. The combination of Particle image\nvelocimetry, Particle tracking velocimetry, Laser induced fluorescence and\nShadowgraphy methods have been applied together with the use of fluorescent\nPMMA seeding particles. An experimental closed water circuit was designed with\na low-pressure water pump, and a series of experiments was conducted to\nmeasure the velocity of seeding particles in the water jet flow below the diamond\nmicro-nozzle outlet. The basic principles of the methods used in experiments are\nalso described.
Keywords:
micro water jet; fluorescent PMMA particles; velocity; LIF; PTV; PIV
Available on request at various institutes of the ASCR
Velocity measurements on continuous micro water jet using fluorescent PMMA seeding particles
The paper deals with application of optical diagnostic techniques for velocity\nmeasurements of continuous micro water jet. The combination of Particle image\nvelocimetry, Particle tracking ...
Community area risk assessment for flash flood
Kolejka, Jaromír; Rapant, P.; Krejčí, Tomáš
2017 - English
The flash floods forecasting is struggling mainly with extraordinary irregularities in origin of causal precipitations. They only in conjunction with the territory water saturation caused by antecedent precipitations start effect of other local factors that can consequences of short-term extreme precipitation either worsen or mitigate vice versa. Other community area features represent a permanent potential for an adequate territory response after heavy rains. According to current knowledge, it is possible to assess the flash floods hazard of a particular territory in case of extreme precipitation in advance. If such precipitations are already on the ground, or if they are just coming up in the atmosphere, the local flood control headquarters has at least time enough to call alarm and issue a flood warning. In the ideal case, it is possible to incorporate such area assessment into the concept of decision-making of the disaster staff and to insert it into the master plan documentation. The aim of this text is to present above mentioned original method, which can be used in authomatic GIS environment by public administration as well as other users. Suggested procedure is based on automatic hydrologic modelling in ArcGIS platform in combination with advanced digital terrain model. Delimitation of partial catchment basins is also part of our proces, which enables to decide about the risk value of the area in more detail using weighted arithmetic mean. These methods result to detailed imagination about probably threatened localities - and it is essential tool for local authorities and their decision making process in case of early warning.
Keywords:
flash flood; local development; risk assessment; planning documentation
Available at various institutes of the ASCR
Community area risk assessment for flash flood
The flash floods forecasting is struggling mainly with extraordinary irregularities in origin of causal precipitations. They only in conjunction with the territory water saturation caused by ...
NRGL provides central access to information on grey literature produced in the Czech Republic in the fields of science, research and education. You can find more information about grey literature and NRGL at service web
Send your suggestions and comments to nusl@techlib.cz
Provider
Other bases