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Chinese Annals of Mathematics,Series B 2006年第5期27卷 507-538页

作者： Hideo kUBO kji kUBOTA Department of Mathematics Osaka University Machikaneyama 1-1ToyonakaOsaka 560-0043Japan Department of Mathematics Hokkaido University Sapporo 060-0810Japan

This paper is concerned with a class of semilinear hyperbolic systems in odd space dimensions. Our main aim is to prove the existence of a small amplitude solution which is asymptotic to the free solution as t →-∞ in the energy norm, and to show it has a free profile as t →＋∞. Our approach is based on the work of [11]. Namely we use a weighted L^∞ norm to get suitable a priori estimates. This can be done by restricting our attention to radially symmetric solutions. Corresponding initial value problem is also considered in an analogous framework. Besides, we give an extended result of [14] for three space dimensional case in Section 5, which is prepared independently of the other parts of the paper.

关键词： Semilinear wave equations Asymptotic behavior Radially symmetric solution

Nomore blind dates with calcite: Fluid-flow vs. fault-slip along the Očkov thrust, Prague Basin

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Geoscience Frontiers 2021年第4期12卷 163-174页

作者： Nick M.W.Roberts jiřížák František Vacek jiříSláma Geochronology and Tracers Facility British Geological SurveyEnvironmental Science CentreNottingham NG125GGUK Institute of Geology and Paleontology Faculty of ScienceCharles UniversityAlbertov 6Prague 12843Czech Republic Department of Mineralogy and Petrology National MuseumVáclavskénáměstí68Prague 11579Czech Republic Institute of Geology Czech Academy of Sciencesv.v.i.Rozvojová269Prague 16500Czech Republic

Dating of fracture-filling calcitewith U-Pb geochronology is becoming a rapidly adopted technique for determining the absolute timing of brittle deformation in the upper *** calcite is a desirable target,as it precipitates between individual fault slip displacement events,and provides additional kinematic *** we present a case study of slickenfibres formed on the Očkov thrust in the Lower Palaezoic Prague Basin,Bohemian Massif,utilising a combination of petrographic and in situ *** demonstrate that slickenfibre external textures can be preserved,whilst internally primary textures are removed by fluid infiltration and recrystallization,leading to variable U and Pb *** slickenfibre yielded a date of ca.250 Ma,which we interpret as recording fault slip along the Očkov *** cross-cutting slickenfibre yielded more scattered U-Pb data,with an imprecise apparent age around ca.95 *** slickenfibre is recrystallised,destroying the primary textures,and exhibits element *** meaning of this younger apparent age is therefore questionable;whereas it likely reflects Cretaceous U and Pb mobility assisted by fluid-flow along the fault plane,it may not reflect a period of fault *** results demonstrate that slickenfibre-based U-Pb dates do not unequivocally relate to fault motion,and that petrographic and elemental analyses are important requirements for interpreting calcite U-Pb data.

关键词： U-Pb geochronology Calcite Fault dating Fluid-flow Prague Basin LA-ICP-MS

Research of Mechanical and Thermal Properties of Composite Material Based on Gypsum and Straw

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Journal of Renewable Materials 2022年第7期10卷 1859-1873页

作者： Nikola Vavřínová kateřina Stejskalová jiříTeslík kateřina kubenková jiříMajer Faculty of Civil Engineering VSB-Technical University of OstravaOstrava70800Czech Republic

This article is focused on the investigation of the mechanical and thermal properties of composite material that could be used for the production of plaster or *** composite material is made of gypsum and reinforcing natural *** article verifies whether this natural reinforcement can improve the investigated properties compared to conventional plasters and gypsum plasterboards made of pure *** this composite material,high-strength plasterboards could then be produced,which meet the higher demands of users than conventional gypsum *** their production,natural waste materials would be used *** part of the development of new building materials,it is necessary to specify essential characteristics for their later use in civil *** wheat straw and three gypsum classes with strengths G2(2 MPa)—gypsum Class I.,G5(5 MPa)—gypsum Class *** G16(16 MPa)—gypsum Class *** used to create the test *** were made with different ratios of the two ingredients,with the percentages of straw being 0%,2.5%,and 5%for each gypsum *** first part of the article describes how the increasing proportion of straw affects the composite’s mechanical properties(flexural strength and compressive strength).The second part of the article focuses on the change of thermal properties(thermal conductivity and specific heat capacity).The last part of the article mentions the verification of the fire properties(single-flame source fire test and gross heat of combustion)of this composite *** research has shown that the increasing proportion of straw reinforcement caused a deterioration in the flexural strength(up to 56.49%in the *** of gypsum Class II.)and compressive strength(up to 80.27%in the *** of gypsum Class III.)and an improvement in the specific heat capacity and thermal conductivity(up to 31.40%in the ***).This composite material is thus not suitable for the production of high-streng

关键词： Composite material gypsum plasterboard crushed straw flexural strength compressive strength thermal conductivity specific heat capacity ignitability gross heat of combustion

Identification of altitude profiles in 3D geovisualizations:the role of interaction and spatial abilities

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International Journal of Digital Earth 2019年第2期12卷 156-172页

作者： Petr kubíček Čeněk Šašinka Zdeněk Stachoň Lukáš Herman Vojtěch Juřík Tomáš Urbánek jiří Chmelík Department of Geography Faculty of ScienceMasaryk UniversityBrnoCzech Republic HUME Lab Faculty of ArtsMasaryk UniversityBrnoCzech Republic Department of Psychology Faculty of ArtsMasaryk UniversityBrnoCzech Republic Department of Computer Graphics and Design Faculty of InformaticsMasaryk UniversityBrnoCzech Republic

Three-dimensional geovisualizations are currently pushed both by technological development and by the demands of experts in various applied *** the presented empirical study,we compared the features of real 3D(stereoscopic)versus pseudo 3D(monoscopic)geovisualizations in static and interactive digital elevation *** tested 39 high-school students in their ability to identify the correct terrain profile from digital elevation ***’performance was recorded and further analysed with respect to their spatial abilities,which were measured by a psychological mental rotation test and think aloud *** results of the study indicated that the influence of the type of 3D visualization(monoscopic/stereoscopic)on the performance of the users is not clear,the level of navigational interactivity has significant influence on the usability of a particular 3D visualization,and finally no influences of the spatial abilities on the performance of the user within the 3D environment were identified.

关键词： 3D geovisualizations stereoscopic and monoscopic 3D vision spatial abilities level of navigational interactivity

No more blind dates with calcite:Fluid-flow ***-slip along the O?kov thrust,Prague Basin

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Geoscience Frontiers 2021年第4期12卷 167-178页

作者： Nick M.W.Roberts ji?í ?ák Franti?ek Vacek ji?í Sláma Geochronology and Tracers Facility British Geological SurveyEnvironmental Science Centre Institute of Geology and Paleontology Faculty of ScienceCharles University Department of Mineralogy and Petrology National Museum Institute of Geology Czech Academy of Sciences

Dating of fracture-filling calcite with U-Pb geochronology is becoming a rapidly adopted technique for determining the absolute timing of brittle deformation in the upper *** calcite is a desirable target,as it precipitates between individual fault slip displacement events,and provides additional kinematic *** we present a case study of slickenfibres formed on the O?kov thrust in the Lower Palaezoic Prague Basin,Bohemian Massif,utilising a combination of petrographic and in situ *** demonstrate that slickenfibre external textures can be preserved,whilst internally primary textures are removed by fluid infiltration and recrystallization,leading to variable U and Pb *** slickenfibre yielded a date of ca.250 Ma,which we interpret as recording fault slip along the O?kov *** cross-cutting slickenfibre yielded more scattered U-Pb data,with an imprecise apparent age around ca.95 *** slickenfibre is recrystallised,destroying the primary textures,and exhibits element *** meaning of this younger apparent age is therefore questionable;whereas it likely reflects Cretaceous U and Pb mobility assisted by fluid-flow along the fault plane,it may not reflect a period of fault *** results demonstrate that slickenfibre-based U-Pb dates do not unequivocally relate to fault motion,and that petrographic and elemental analyses are important requirements for interpreting calcite U-Pb data.

关键词： U-Pb geochronology Calcite Fault dating Fluid-flow Prague Basin LA-ICP-MS

Making the Genotypic Variation Visible:Hyperspectral Phenotyping in Scots Pine Seedlings

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Plant Phenomics 2023年第4期5卷 790-804页

作者： Jan Stejskal Jaroslav Čepl Eva Neuwirthová Olusegun Olaitan Akinyemi jiří Chuchlík Daniel Provazník Markku keinänen Petya Campbell Jana Albrechtová Milan Lstiburek Zuzana Lhotáková Department of Genetics and Physiology of Forest Trees Faculty of Forestry and Wood SciencesCzech University of Life Sciences PraguePragueCzech Republic Department of Environmental and Biological Sciences University of Eastern FinlandJoensuuFinland Department of Experimental Plant Biology Charles UniversityPragueCzech Republic Center for Photonic Sciences University of Eastern FinlandJoensuuFinland Department of Geography and Environmental Sciences University of Maryland Baltimore CountyBaltimoreMDUSA Biospheric Sciences Laboratory NASA Goddard Space Flight CenterGreenbeltMDUSA

Hyperspectral reflectance contains valuable information about leaf functional traits,which can indicate a plant's physiological ***,using hyperspectral reflectance for high-throughput phenotyping of foliar traits could be a powerful tool for tree breeders and nursery practitioners to distinguish and select seedlings with desired adaptation potential to local *** evaluated the use of 2 nondestructive methods(i.e.,leaf and proximal/canopy)measuring hyperspectral reflectance in the 350-to 2,500-nm range for phenotyping on 1,788 individual Scots pine seedlings belonging to lowland and upland ecotypes of 3 different local populations from the Czech ***-level measurements were collected using a spectroradiometer and a contact probe with an internal light source to measure the biconical reflectance factor of a sample of needles placed on a black background in the contact probe field of *** proximal canopy measurements were collected under natural solar light,using the same spectroradiometer with fiber optical cable to collect data on individual seedlings'hemispherical conical reflectance *** latter method was highly susceptible to changes in incoming *** spectral datasets showed statistically significant differences among Scots pine populations in the whole spectral ***,using random forest and support vector machine learning algorithms,the proximal data obtained from the top of the seedlings offered up to 83%accuracy in predicting 3 different Scots pine *** conclude that both approaches are viable for hyperspectral phenotyping to disentangle the phenotypic and the underlying genetic variation within Scots pine seedlings.

关键词： Scots forest reflectance

High-resolution genome-wide association study of a large Czech collection of sweet cherry (Prunus avium L.) on fruit maturity and quality traits

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Horticulture Research 2023年第1期10卷 113-127页

作者： kateřina Holušová JanaČmejlová Pavol Suran RadekČmejla jiříSedlák Lubor Zelený Jan Bartoš Centre of the Region Hanáfor Biotechnological and Agricultural Research Institute of Experimental Botany of the Czech Academy of Sciencesšlechtitelu 31Olomouc77900Czech Republic Research and Breeding Institute of Pomology Holovousy Ltd. Holovousy 129Holovousy50801Czech Republic

In sweet cherry(Prunus avium L.),quantitative trait loci have been identified for fruit maturity,colour,firmness,and size to develop markers for marker-assisted ***,resolution is usually too low in those analyses to directly target candidate genes,and some associations are *** contrast,genome-wide association studies are performed on broad collections of accessions,and assemblies of reference sequences from Tieton and Satonishiki cultivars enable identification of single nucleotide polymorphisms after whole-genome sequencing,providing high marker *** hundred and thirty-five sweet cherry accessions were sequenced and phenotyped for harvest time and fruit colour,firmness,and ***-wide association studies were used to identify single nucleotide polymorphisms associated with each trait,which were verified in breeding material consisting of 64 additional accessions.A total of 1767106 single nucleotide polymorphisms were *** that density,significant single nucleotide polymorphisms could be linked to co-inherited haplotype blocks(median size∼10 kb).Thus,markers were tightly associated with respective phenotypes,and individual allelic combinations of particular single nucleotide polymorphisms provided links to distinct *** addition,yellow-fruit accessions were sequenced,and a∼90-kb-deletion on chromosome 3 that included five MYB10 transcription factors was associated with the ***,the study confirmed numerous quantitative trait loci from bi-parental populations using high-diversity accession populations,identified novel associations,and genome-wide association studies reduced the size of trait-associated loci from megabases to kilobases and to a few candidate genes per ***,a framework is provided to develop molecular markers and evaluate and characterize genes underlying important agronomic traits.

关键词： fir breeding maturity

The significance of cherts as markers of Ocean Plate Stratigraphy and paleoenvironmental conditions:New insights from the Neoproterozoic-Cambrian Blovice accretionary wedge,Bohemian Massif

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Geoscience Frontiers 2023年第1期14卷 162-180页

作者： LukášAckerman jirízák Václav kachlík Jan Pašava karelZák Andreas Pack František Veselovsky Ladislav Strnad Institute of Geology of the Czech Academy of Sciences Rozvojová269CZ-16500 Prague 6Czech Republic Czech Geological Survey Klárov3CZ-11821 Prague 1Czech Republic Institute of Geology and Paleontology Faculty of ScienceCharles UniversityAlbertov 6Prague 12843Czech Republic Geowissenschaftliches Zentrum Universität GöttingenGoldschmidtstraβe 1D-37077 GöttingenGermany Laboratories of the Geological Institutes Faculty of ScienceCharles UniversityAlbertov 6Prague 12843Czech Republic

The Ediacaran to early Cambrian Blovice accretionary complex,Bohemian Massif,hosts abundant chert bodies that formed on an oceanic plate and were involved in subduction beneath the northern margin of *** relationships of cherts to their host,their microstructure and elemental as well as isotopic compositions revealed diverse processes of chert petrogenesis reflecting depositional environment and position on the oceanic *** deep-water cherts formed through a hydrothermal precipitation of silica-rich gels on outer trench swell of the subducted slab with none or only minor addition of terrigenous *** the contrary,the shallow-water cherts formed in lagoons on seamount slopes,and at least some of them represent a product of hydrothermal replacement of former carbonate and/or evaporite *** both chert types,the hydrothermal fluids were of low temperature and continuous pervasive hydrothermal alteration of oceanic crust,together with an elevated Si content in Neoproterozoic seawater,served as the major source of *** the other hand,minor carbon enrichment in chert is mostly linked to variable incorporation of organic matter that was deposited on the *** earth element(REE)systematics of the cherts indicate predominantly oxygenated environment for the shallow-water cherts whereas the deep-water cherts were deposited in diverse redox conditions,depending on their distance from hydrothermal *** these data,we demonstrate that the cherts once formed a part of Ocean Plate Stratigraphy(OPS)now dismembered and mixed with terrigenous siliciclastic material to form OPS mé*** our data with those from the existing literature,we show that cherts can serve as significant markers of OPS since the Archean,recording a complex interplay between seafloor-related volcanic(production of MORB-and OIB-like magmas)and sedimentary processes,hydrothermal activity at mid-ocean ridges and seamount chains as well as at outer slopes o

关键词： Chert Accretionary wedge Ediacaran Triple oxygen isotopes Strontium isotopes Ocean Plate Stratigraphy

Mathematical and Computational Methods in Biomechanics of Human Skeletal Systems: An Introduction 1

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Brain age estimation:premise,promise,and problems

丛书名： Wiley Series on Bioinformatics: Computational Techniques and Engineering

2011年

作者： jiří Nedoma jiří Stehlík Ivan Hlaváček Josef Daněk Tatjana Dostálová Petra Přečková

ISBN: (数字)9781118006474

ISBN: (纸本)9780470408247

Cutting-edge solutions to current problems in orthopedics, supported by modeling and numerical analysis Despite the current successful methods and achievements of good joint implantations, it is essential to further optimize the shape of implants so they may better resist extreme long-term mechanical demands. This book provides the orthopedic, biomechanical, and mathematical basis for the simulation of surgical techniques in orthopedics. It focuses on the numerical modeling of total human joint replacements and simulation of their functions, along with the rigorous biomechanics of human joints and other skeletal parts. The book includes: An introduction to the anatomy and biomechanics of the human skeleton, biomaterials, and problems of alloarthroplasty The definition of selected simulated orthopedic problems Constructions of mathematical model problems of the biomechanics of the human skeleton and its parts Replacement parts of the human skeleton and corresponding mathematical model problems Detailed mathematical analyses of mathematical models based on functional analysis and finite element methods Biomechanical analyses of particular parts of the human skeleton, joints, and corresponding replacements A discussion of the problems of data processing from nuclear magnetic resonance imaging and computer tomography This timely book offers a wealth of information on the current research in this field. The theories presented are applied to specific problems of orthopedics. Numerical results are presented and discussed from both biomechanical and orthopedic points of view and treatment methods are also briefly addressed. Emphasis is placed on the variational approach to the investigated model problems while preserving the orthopedic nature of the investigated problems. The book also presents a study of algorithmic procedures based on these simulation models. This is a highly useful tool for designers, researchers, and manufacturers of joint implants who require the resul

关键词： Biomechanics.Human mechanicsMathematics.Musculoskeletal systemMathematical models.Artificial jointsMathematical models.Biomechanics.Arthroplasty Replacement.Jointssurgery.Models Theoretical.

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Neural Regeneration Research 2025年第8期20卷 2313-2314页

作者： Jarrad Perron ji Hyun ko Graduate Program in Biomedical Engineering Price Faculty of EngineeringUniversity of ManitobaWinnipegMBCanada PrairieNeuro Research Centre Kleysen Institute for Advanced MedicineHealth Sciences CentreWinnipegMBCanada Department of Human Anatomy and Cell Science Rady Faculty of Health SciencesUniversity of ManitobaWinnipegMBCanada

Premise:The com bined effects of modern healthcare practices which prolong lifespan and declining birthrates have created unprecedented changes in age demographics worldwide that are especially pronounced in Japan,South korea,Europe,and North *** old age is the most significant predictor of dementia,global healthcare systems must rise to the challenge of providing care for those with neurodegenerative disorders.

关键词： estimation providing birth