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The X-ray CT lab and the research at the Institute of Geonics AS CR
Souček, Kamil; Staš, Lubomír
2014 - English
In recent decades, non-destructive methods of materials analysis (Desrues 2006) have been used increasingly for the study of different kinds of materials. Especially, it concerns the method of the X-ray computed tomography (CT). This technique was invented in 1970's (Hounsfield 1972) and it quickly became an indispensable part of medicine. In the 1980's, this success in medicine encouraged the research and development of the X-ray CT applications in the field of materials engineering and consequently also in the field of geomaterials (Otani, Obara 2004). Nowadays, many applications are possible due to high resolution of individual building units in the tomographic cross-sections (so called voxels) with dimensions of units or tens of micrometres. To get this resolution, the use of the 2D and the 3D high-resolution X-ray CT, or the micro-CT with micro-focal sources of X-rays, and suitable linear or flat (2D) X-Ray detectors are preferred.
Keywords:
X-Ray computed tomography; non-destructive investigation of geomaterials; X-ray CT lab; rentgenové záření; materiály
Available in digital repository of the ASCR
The X-ray CT lab and the research at the Institute of Geonics AS CR
In recent decades, non-destructive methods of materials analysis (Desrues 2006) have been used increasingly for the study of different kinds of materials. Especially, it concerns the method of the ...
Brownfields in Karviná: Opportunity or Threat?
Martinát, Stanislav; Cyroňová, K.; Dvořák, Petr; Klusáček, Petr
2014 - Czech
Brownfields are in creasingly discussed topic among researchers and public administration representatives as well. Especially in peripheral areas and in regions affected by structural changes is an issue of brownfields due to their limited attractiveness for investments very specific. This paper aims to comment the issue of brownfields in the above type of area on the example of city of Karviná. The theoretical part of the paper discusses the economic, social and environmental aspects of brownfield regeneration. Then spatial analysis of these areas brownfields on the area studied city is Sborník p ř ísp ě vk ů X VII . mezinárodní kolokvium o regionálních v ě dách Hustope č e 18. – 20 . 6. 20 14 622 carried on from the point of view of their size, previous use, type of ownership, contamination and location within the city. The specifics of regeneration of mining brownfields are then formu lated. In the last part of the paper thematic survey conducted among the population of the city of Karviná (n = 150) is evaluated. The survey aimed to determine preferences for future use of brownfields and general perception of these areas by local popula tion. Brownfieldy jsou stále více diskutovaným tématem mezi výzkumníky i ve ř ejnou správou. Zvlá š t ě v periferních oblastech a v regionech posti ž ených strukturálními zm ě nami je problém brownfield ů s ohledem na jejich omezenou atraktivitu pro investory velmi specifický. P ř ísp ě vek se sna ž í komentovat problematiku brownfield ů ve vý š e uvedeném typu území na p ř íklad ě m ě sta Karviná. Ve své teoretické č ásti p ř ísp ě vek diskutuj e nad ekonomickými, sociálními a environmentálními aspekty regenerace brownfield ů , na co ž navazuje prostorová analýza t ě chto ploch na území Karviné, v jejím ž rámci zkoumána jejich velikost, p ř edchozí vyu ž ití, typ vlastnictví, kontaminace a umíst ě ní v rámci m ě sta. Jsou formulována specifika regenerace t ěž ebních brownfield ů . V poslední č ásti p ř ísp ě vku je vyhodnoceno tematické dotazníkové š et ř ení provedené mezi obyvatelstvem m ě sta (n=150), v n ě m ž byly zji šť ovány preference budoucího vyu ž ití brownfield ů a obecn ě percepce t ě chto ploch místními obyvateli. V záv ě ru jsou formulována doporu č ení jak ve ř ejné správ ě , tak investor ů m, jak p ř istupovat k problematice brownfield ů
Keywords:
brownfieldy; Karviná; Czech Republic; regeneration
Fulltext is available at external website.
Brownfields in Karviná: Opportunity or Threat?
Brownfields are in creasingly discussed topic among researchers and public administration representatives as well. Especially in peripheral areas and in regions affected by structural changes is an ...
Stability of suspension bridges in lateral wind
Malík, Josef
2014 - English
The collapse of the original Tacoma suspension bridge has been studied in many papers. On 7 November 1940 around 10 a.m. the torsional oscillations appeared on the deck of the original Tacoma bridge after the loosening of one midspan cable band, which resulted in the lateral asymmetry of the construction. It seems that the loosening of the midspan cable band had a significant impact on the behavior of the bridge and in the end it resulted in the collapse.
Keywords:
stability; suspension bridges; torsional oscillations
Available in a digital repository NRGL
Stability of suspension bridges in lateral wind
The collapse of the original Tacoma suspension bridge has been studied in many papers. On 7 November 1940 around 10 a.m. the torsional oscillations appeared on the deck of the original Tacoma bridge ...
The Analysis of Material Inner Structure and Industry X-ray Computed Microtomography
Souček, Kamil
2014 - Czech
In recent decades, non-destructive methods of materials analysis have been used increasingly for the study of different kinds of materials. Especially, it concerns the method of the X-ray industry computed microtomography (CT). This paper is elaborated on the basis of the experiences of X-ray CT use within the frame of research activities of the Institute of Geonics ASCR. Particularly, the possibilities and examples of the different kind material research by X-ray CT are presented. The X-ray CT systems fy. Nikom Metrology X TH 225 ST and XT H 450 at Institute of Geonics cover a wide range of the X-ray CT and radiography applications in the fields of analysis of materials and geomaterials (e.g. analysis of the pore space, inner structure and their defects), the inspection of small castings and plastic parts, as well as in the fields of palaeontology (e.g. inspection of bones, sculls, fossils etc.), size measurement of internal dimensions of the components, defectoscopy of machines and equipment parts and also in the field of biological structures analysis. V současné době jsou stále častěji využívány nedestruktivní metody analýzy různých typů materiálů. Jednu z takovýchto metod představuje především průmyslová rentgenová počítačová mikrotomografie (CT). Tento příspěvek je zpracován na základě zkušeností používání rentgenové průmyslové počítačové mikrotomografie v rámci výzkumných aktivit Ústavu geoniky AV ČR a pojednává o možnostech výzkumu různých typů materiálů pomocí této metody, včetně příkladů jejího použití. Rentgenové CT systémy firmy Nikom Metrology X TH 225 ST a XT H 450 na Ústavu geoniky pokrývají širokou oblast tomografických a radiografických aplikací, například v oblasti analýzy materiálů a geomateriálů (např. analýza pórového prostoru, vnitřní stavby a jejich defektů), stejně tak jako v oblasti kontroly malých odlitků a plastových dílů, v oblasti paleontologie (např. kontrola kosti, lebek, fosílií apod.), měření velikosti vnitřních rozměrů součástek, defektoskopie strojů a částí zařízení a rovněž v oblasti analýzy biologických struktur.
Keywords:
X-ray computed microtomography; inner structure of materials; porosity; defectoscopy
Available in a digital repository NRGL
The Analysis of Material Inner Structure and Industry X-ray Computed Microtomography
In recent decades, non-destructive methods of materials analysis have been used increasingly for the study of different kinds of materials. Especially, it concerns the method of the X-ray industry ...
Geosite and geomorphosite assessment for geotourism purposes: a case study from the Vizovická vrchovina Highland, Eastern Moravia
Kirchner, Karel; Kubalíková, L.
2014 - English
Contribution deals with the problem of geodiversity, geoheritage and possibilities of their assessment for geotourism purposes. Geological, geomorphological and pedological sites are the most important resource for the geotourism activities. To find out which site can be used, it is necessary to identify, describe and assess various sites using a suitable assessment methodology. Based on the definition and concepts of geotourism and the assessment methods already used for geomorphosite assessment, authors propose five groups of assessment criteria. The method was used for assessing selected sites in the Vizovická vrchovina Highland.
Keywords:
geodiversity; numerical assessment; Outer Western Carpathians
Available in a digital repository NRGL
Geosite and geomorphosite assessment for geotourism purposes: a case study from the Vizovická vrchovina Highland, Eastern Moravia
Contribution deals with the problem of geodiversity, geoheritage and possibilities of their assessment for geotourism purposes. Geological, geomorphological and pedological sites are the most ...
Optimization methods for inverse problems with energy norm
Hrtus, Rostislav; Haslinger, Jaroslav; Blaheta, Radim
2014 - English
The paper deals with the application of the energy norm in the inverse problem which is based on a minimization of a nonlinear least squares function. Three different parameter distribution examples are solved by the steepest descent, nonlinear conjugate gradient and Newton methods. Efficiency comparison is also presented.
Keywords:
optimization methods; parameter distribution; Newton methods
Available in a digital repository NRGL
Optimization methods for inverse problems with energy norm
The paper deals with the application of the energy norm in the inverse problem which is based on a minimization of a nonlinear least squares function. Three different parameter distribution examples ...
Selected aspects from monitoring mine rescuers´ exposure to heat
Pavelek, Zdeněk
2014 - Czech
The responses of mine rescuers in worsened microclimatic conditions are among the most arduous and risky operations undertaken by mine rescue crews. The standard method of monitoring mine rescuers´ exposure to heat consists of manually measuring the temperature (relative humidity) of the mine atmosphere both en route and on site and further, of monitoring the actual physical condition of mine rescuers by measuring their pulse rate. From the measurement of the temperature (relative humidity) in the mine atmosphere, the duration of responses without wearing breathing apparatuses, or when wearing them, can subsequently be determined by means of tabulated values. New trends in monitoring the mine rescuers´ exposure to heat mainly accentuate continuous evaluation of the current physical condition of every individual mine rescuer in action, while this evaluation is based on continuous measurement of the physiological quantities of physical organism. This method of monitoring mine rescuers´ exposure to heat represents a significant improvement in safety when guiding responses of mine rescue services during mining activity in underground mines. Zásahy báňských záchranářů ve ztížených mikroklimatických podmínkách patří mezi nejobtížnější a také nejrizikovější zásahové činnosti báňského záchranného sboru. Standardně používaná metoda monitoringu tepelné expozice báňských záchranářů spočívá v manuálním měření teplot (relativní vlhkosti) důlního ovzduší při cestě na pracovišti a na pracovišti samotném a dále ve sledování aktuálního tělesného stavu báňských záchranářů měřením jejich tepové frekvence. Z měření teplot (relativní vlhkosti) důlního ovzduší je následně tabelárně stanovována délka doby zásahu bez dýchacích přístrojů i s nasazenými dýchacími přístroji. Nové směry v monitoringu tepelné expozice báňských záchranářů s sebou přinášejí především akcentaci kontinuálního hodnocení aktuálního tělesného stavu každého jednotlivého zasahujícího báňského záchranáře, přičemž toto hodnocení je založeno na průběžném měřením fyziologických veličin tělesného organismu. Tento způsob monitoringu tepelné expozice báňských záchranářů představuje výrazné zvýšení míry bezpečnosti vedení zásahové činnosti báňského záchranné služby při hornické činnosti v hlubinných dolech.
Keywords:
mine rescuers; worsened microclimatic conditions; risky operations
Available at various institutes of the ASCR
Selected aspects from monitoring mine rescuers´ exposure to heat
The responses of mine rescuers in worsened microclimatic conditions are among the most arduous and risky operations undertaken by mine rescue crews. The standard method of monitoring mine rescuers´ ...
Flash floods in the Czech lands on examples from the 16th – 21st centuries
Munzar, Jan; Ondráček, Stanislav
2014 - Czech
An often discussed and still topical question is whether the frequency of the occurrence of flash floods has been increasing in the last decennia or the impression results only from the increased interest (and improved technical possibilities) of media and wide public in these extreme hydro-meteorological phenomena. There are many floods of this type that can be documented from the past, which occurred before the hydro-meteorological measurements. Although they did not affect vast areas, they usually represented (similarly as today) crushing disasters for the hit territories. The contribution brings examples of such extremes from the end of the 16th century to the beginning of the 21st century, which went down in the flood history of the affected areas. Často diskutovanou a stále aktuální otázkou je, zda se v posledních desetiletích zvyšuje četnost výskytu přívalových povodní nebo je to dáno jen větším zájmem (i technickými možnostmi) médií a širší veřejnosti o tyto extrémní hydrometeorologické jevy. Z minulosti lze však doložit řadu případů povodní tohoto typu, ke kterým docházelo samozřejmě i před počátkem hydrometeorologických měření. Nepostihovaly sice rozsáhlé oblasti, ale pro zasažené území většinou znamenaly (stejně jako dnes) zničující katastrofu. V příspěvku jsou uvedeny příklady takovýchto extrémů od konce 16. do počátku 21. století, které se zapsaly do povodňové historie postižených území.
Keywords:
flash floods; 16th-21st centuries; Czech lands
Available in digital repository of the ASCR
Flash floods in the Czech lands on examples from the 16th – 21st centuries
An often discussed and still topical question is whether the frequency of the occurrence of flash floods has been increasing in the last decennia or the impression results only from the increased ...
Analysis of Brownfields Regeneration Occasions: Liberecký Region Example
Černík, J.; Kunc, Josef
2014 - Czech
Brownfield is any land degenerated by it ́s previous use. Such areas (and structures in this area) may currently be vacant and it represents a barrier in future balanced development of the area and surroundings. This contribu tion targets on describing the ability of brownfields remediation by using the Principal Component Analysis of socio - economic, spatial and demographic indicators. As a study area was set up the Liberece region. From results it is clear that selected indica tors can satisfactorily describe the ability for remediation only by agricultural brownfields. Regarding to the type of analysed data we can presuppose a significant influence of soft factors on brownfield remediation. Such factors may describe the role of active participation of stakeholders, private motivating factors, inspiration in case of best practices, etc. Za brownfields pova ž ujeme území, je ž jsou deprimována po svém p ř edchozím vyu ž ití. V sou č asnosti pozbyla tato území a objekty, které se na nich nachází, vyu ž ití a vytvá ř í tak p ř eká ž ku v dal š ím rovnová ž ném rozvoji území. Cílem p ř edkládaného p ř ísp ě vku je, na základ ě faktorové analýzy hlavních komponent ovliv ň ujících regeneraci brownfields, identifikace socio - ekonomických, prostorových a demografických faktor ů , je ž mají vliv na regeneraci brownfields na p ř íkladu Libereckého kraje. Z výsledk ů je patrné, ž e zvolené ukazatele mají prokazatelný vliv pouze na regeneraci brownfields zem ě d ě lského p ů vodu. Vzhledem k charakteru analyzovaných dat se lze domnívat, ž e u p oz ů statk ů jiných č inností hrají významn ější roli tzv. měkké faktory, především aktivní participace dotčených stran, jejich osobní motivace, inspirace dobrými příklady regenerace, apod.
Keywords:
brownfileds; regeneration; factor analysis; Liberecký region; the Czech Republic
Fulltext is available at external website.
Analysis of Brownfields Regeneration Occasions: Liberecký Region Example
Brownfield is any land degenerated by it ́s previous use. Such areas (and structures in this area) may currently be vacant and it represents a barrier in future balanced development of the area and ...
Slightly generalized regular space decompositions
Kolcun, Alexej
2014 - English
Space decomposition methods represent an important part of numerical modelling process. In many applications it is suitable to use the simplest case of decomposition { regular rectangular grid: the whole raster graphic concept can be seen from this point of view. Dierent raster concept, based on regular hexagonal mesh, is analyzed e.g. in [18]. Generalized task { decomposition of the space to the set of the identical elements have been presented in various research areas since a long time, and it is connected with Hilbert's 18th problem [9], [10].
Keywords:
space decomposition methods; numerical modelling; discretization
Available in a digital repository NRGL
Slightly generalized regular space decompositions
Space decomposition methods represent an important part of numerical modelling process. In many applications it is suitable to use the simplest case of decomposition { regular rectangular grid: the ...
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