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Influence of environmental predispositions on temperate mountain forest damage at different spatial scales during alternating drought and flood periods:case study in Hruby Jeseník Mts.(Czech Republic)

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Journal of Mountain Science 2022年第7期19卷 1931-1944页

作者： pavel SAMEC Romana KUDELKOVA Petr LUKES Ales KUCERA pavel CUDLIN Global Change Research Institute CAS Bělidla 986/4aBrnoCZ-60300Czech Republic Department of Geology and Soil Science Faculty of Forestry and Wood TechnologyMendel University in BrnoZemědělská3BRNOCZ-61300Czech Republic Department of Geoinformatics Faculty of SciencePalacky University Olomouc17.listopadu 50OlomoucCZ-77900Czech Republic

Mountain forests are more prone to environmental predispositions(EPs)than submountain *** remote sensing of mountain forests enables instantaneous damage mapping,the investigation of the causes requires field ***,a local field or regionally modeled environmental characteristics influence remote data evaluation *** study focused on the evaluation of EPs effects damaging mountain forests between various spatial resolutions during environmental *** evaluation was divided into managed and natural forests in the Hruby Jeseník Mts.(Czech Republic;240-1491 m a.s.l.;50.082°N,17.231°E).Damage was assessed through the discrimination analysis of the normalised difference vegetation index(NDVI)by MODIS VI during alternating drought and flood periods *** local environmental influence was assessed using the discrimination function(DF)separability of forest damage in the training *** regional influence was assessed through map algebra estimated via the DF and a forest decline spatial model based on EPs from differences between risk growth conditions and biomass fuzzy ***,EPs and soil influenced forest NDVI at different *** management afflicted the NDVI more than the *** EPs afflicted the NDVI more than the soil *** winters and droughts had a greater influence on the NDVI than the flood events,with the winter of 2005/2006 inverting the DF direction,and the 2003 drought increasing differences in managed forest biomass and decreasing differences in natural forest *** than 50% of declining managed forests in the training sets occurred on Leptosols,Podzols and *** a regional scale,the soil influence was eliminated by multiple *** EPs influenced 96% of natural forest and 65% of managed forest,though managed forest damage was more *** mountain forest NDVI decline was dependent on both management and risk predispositions.

关键词： Mountain environment Forest damage types Canopy density Soil group Norway spruce(Picea abies)

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Selected aspects of dielectric behavior of plasma sprayed titanates

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Journal of Advanced Ceramics 2012年第1期1卷 50-59页

作者： pavel CTIBOR Josef SEDLACEK Institute of Plasma Physics ASCRv.v.i.Za Slovankou 3PragueCzech Republic Department of Electrotechnology Faculty of Electrical EngineeringCzech Technical UniversityTechnicka 2PragueCzech Republic

XRD measurements were carried out on plasma sprayed titanates BaTiO_(3),CaTiO_(3),MgTiO_(3)and a mixture of the last *** were tested as dielectrics and volume resistivities of the materials were also *** microscopy was used for mapping of the dielectric response of selected *** results show differences in the crystal structure between plasma sprayed coatings and feedstock powders in the case of BaTiO_(3)and MgTiO_(3)whereas CaTiO_(3)is crystalograffically identical with its *** reason can be found in larger sensitivity of BaTiO_(3)and MgTiO_(3)to the reductive conditions at plasma spraying whereas CaTiO_(3)seems to be rather inert from this *** CaTiO_(3)exhibits anomalous dielectric losses because of intrinsic conductivity.

关键词： plasma spraying dielectric properties electrical properties BaTiO3 and titanates capacitors

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Supersonic Flow Structure in the Entrance Part of a Mixing Chamber of 2D Model Ejector

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Journal of Thermal Science 2003年第4期12卷 344-349页

作者： Vaclav Dvorak pavel Safarik Technical University in Liberec Faculty of Mechanical Engineering Department of Power Engineering Equipment. Halkova 6461 17 Liberec Czech RepublicCzech Technical University in Prague Faculty of Mechanical Engineering 207.1 Institute of Fluid Dynamics and Power Engineering Division of Fluid Dynamics and Thermodynamics. Technicka 4 166 07 Praha 6 Czech Republic

The paper deals with experimental and numerical results of investigation into supersonic and transonic flow past a two-dimensional model ejector. Results of optical measurements show a flow structure and flow parameter development in the entrance part of the mixing chamber of the ejector. Numerical results are obtained by means of both the straight solution of shock waves in supersonic flow field using classical relations of parameters of shock waves and the Fluent 6 program. Results of numerical solutions are compared with experimental pictures of flow fields. Flow structure development in the mixing chamber is analysed in detail.

关键词： supersonic ejector shock waves shear layers mixing process boundary layer separation.

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Migration Algorithm:A New Human-BasedMetaheuristic Approach for Solving Optimization Problems

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Computer Modeling in Engineering & Sciences 2023年第11期137卷 1695-1730页

作者： pavel Trojovsky Mohammad Dehghani Department of Mathematics Faculty of ScienceUniversity of Hradec KrálovéHradec Králové50003Czech Republic

This paper introduces a newmetaheuristic algorithmcalledMigration Algorithm(MA),which is helpful in solving optimization *** fundamental inspiration of MA is the process of human migration,which aims to improve job,educational,economic,and living conditions,and so *** of the proposed MAis presented in two phases to empower the proposed approach in exploration and exploitation during the search *** the exploration phase,the algorithm population is updated based on the simulation of choosing the migration destination among the available *** the exploitation phase,the algorithm population is updated based on the efforts of individuals in the migration destination to adapt to the new environment and improve their ***’s performance is evaluated on fifty-two standard benchmark functions consisting of unimodal and multimodal types and the CEC 2017 test *** addition,MA’s results are compared with the performance of twelve well-known metaheuristic *** optimization results show the proposed MA approach’s high ability to balance exploration and exploitation to achieve suitable solutions for optimization *** analysis and comparison of the simulation results show that MA has provided superior performance against competitor algorithms in most benchmark ***,the implementation of MA on four engineering design problems indicates the effective capability of the proposed approach in handling optimization tasks in real-world applications.

关键词： Optimization metaheuristic migration human-based algorithm exploration exploitation

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Analysis of the Caratheodory's Theorem on Dynamical System Trajectories Under Numerical Uncertainty

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IEEE/CAA Journal of Automatica Sinica 2018年第4期5卷 787-793页

作者： pavel Osinenko Grigory Devadze Stefan Streif Automatic Control and System Dynamics Laboratory Technische Universitat Chemnitz09107 ChemnitzGermany IEEE

The current work proposes a new and constructive proof for the Caratheodory's theorem on existence and uniqueness of trajectories of dynamical systems. The key concern is the numerical uncertainty, i.e., the discrepancy between mathematical proofs, algorithms, and their implementations, which may affect the correct functioning of a control system. Due to growing demands on security and compliance with specifications,correctness of the control system functioning is becoming ever more important. Since in both dynamical systems and many control design approaches, one of the central notions is the system trajectory, it is important to address existence and uniqueness of system trajectories in a way which incorporates numerical uncertainty. Constructive analysis is a particular approach to formalizing numerical uncertainty and is used as the basis of the current work. The major difficulties of guaranteeing existence and uniqueness of system trajectories arise in the case of systems and controllers which possess discontinuities in time,since classical solutions to initial value problems do not *** issue is addressed in Caratheodory's theorem. A particular constructive variant of the theorem is proven which covers a large class of problems found in practice.

关键词： Constructive analysis Caratheodory’s theorem dynamical systems

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Analytical and Numerical Modifications of Transonic Nozzle Flows

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Journal of Thermal Science 2018年第4期27卷 382-388页

作者： Jiri STODULKA Helmut SOBIECZKY pavel SAFARIK CTU in Prague Faculty of Mechanical Engineering Dpt. of Fluid Dynamics and Thermodynamics TU Wien Institute of Technology

Classical transonic hodograph-based design methods are employed and revitalized using modern numerical tools to illustrate the design of a symmetrical accelerating-decelerating nozzle throat design. The concept of Elliptic Continuation is applied to solve transonic boundary value problems avoiding the inherently nonlinear nature of the basic equations and obtaining transonic flow examples using the Method of Characteristics in an inverse mode. Purpose of the present paper, besides describing a new special flow example, is to keep these classical methods alive for education of a new generation of creative engineers.

关键词： transonic design characteristics nozzle throat fictitious gas

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长江中下游不同小麦品种淀粉特性及产量的差异性分析

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湖北农业科学 2024年第10期 1-7页

作者：史丽丽李梦娟李慕嵘 KEM SENOU pavel DARYL 王小燕湿地生态与农业利用教育部工程研究中心/长江大学农学院

为揭示长江中下游不同小麦（Triticum aestivum L.）品种的淀粉特性及产量间差异，寻找更适宜在该地区生长的优良小麦品种，对15个小麦品种的淀粉特性、沉淀值、蛋白质含量及产量进行分析。结果表明，各小麦品种间的淀粉糊化特性、淀粉... 详细信息

为揭示长江中下游不同小麦（Triticum aestivum L.）品种的淀粉特性及产量间差异，寻找更适宜在该地区生长的优良小麦品种，对15个小麦品种的淀粉特性、沉淀值、蛋白质含量及产量进行分析。结果表明，各小麦品种间的淀粉糊化特性、淀粉冻融稳定性和淀粉含量差异较大，其中，宁麦9号和鄂麦006的糊化特性在一定程度上优于其他品种，且这2个品种的淀粉冻融稳定性表现较好、淀粉含量也较高。不同小麦品种间沉淀值存在显著差异，襄麦55和荆麦102沉淀值较高，分别为10.67 mL和8.00 mL。在15个品种中产量居前三位的依次为荆麦102、鄂麦596和漯麦6010，宁麦9号和鄂麦006产量居中。综上所述，荆麦102、鄂麦596和漯麦6010在长江中下游平原区种植可获得高产，而宁麦9号和鄂麦006在长江中下游平原区种植淀粉品质较优，故这些品种可以成为后续推广的优良品种。

关键词：小麦(Triticum aestivum L.) 品种淀粉特性糊化特性产量长江中下游

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Terahertz frequency selective surfaces using heterostructures based on two-dimensional diffraction grating of single-walled carbon nanotubes

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International Journal of Smart and Nano Materials 2023年第1期14卷 21-35页

作者： pavel Evgenjevich Timoshenko Alexander Lerer Sergei Bernardovich Rochal pavel E.Timoshenko Faculty of Physics Southern Federal UniversityRostov-on-DonRussia Southern Federal University Rostov-on-DonRussia

For single-walled carbon nanotubes(SWCNTs)with a length of 1-50μm,the surface plasmon-polariton(SPP)resonance is within the terahertz frequency range;therefore,SWCNT lattices can be used to design frequency-selective surface(FSS).A numerical model of electromagnetic wave diffraction on a two-dimensional periodic SWCNT lattice can be described by an integro-differential equation of the second-order with respect to the surface current along *** equation can be solved by the Bubnov-Galerkin *** dependence of reflecting and transmitting electromagnetic waves for FSSs near the SPP resonance is studied *** is shown that the resonances are within the lowerfrequency part of the terahertz *** also estimate the relaxa-tion frequency of an individual SWCNT and demonstrate the applic-ability of the Kubo formula for graphene conductivity to array of strips similar in size to SWCNTs under consideration.

关键词： Carbon nanotubes gratings graphene surface plasmon polaritons dielectric response functions

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Definition of the Seismic Field of the Underground Sources in the Ambient Seismic Noise in the Tien Shan Region Using a Three-Component Gradient System

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Journal of Earth Science 2020年第5期31卷 988-992页

作者： Anatoly Kuzmich Rybin Elena Anatol'evna Bataleva Kseniia Sergeevna Nepeina pavel Alexandrovich Kaznacheev pavel Alexandrovich Matiukov pavel Nikolaevich Aleksandrov Research Station of the Russian Academy of Sciences Bishkek 720049Kyrgyz Republic The Schmidt Institute of Physics of the Earth of the Russian Academy of Sciences Moscow 123242Russia Geoelectromagnetic Research Center of the Schmidt Institute of Physics of the Earth of the Russian Academy of Sciences Troitsk 108840Russia

This paper considers a new approach to solving the problem of quantitative estimation of the microseism energy for underground sources that is based on the synthesis of noise interferometry and the passive seismic method of the gradient system. The selection of a seismic field of the underground sources is considered in an experiment conducted in the Tien Shan region. The peculiarities of approach include the separation of vertical microseisms in the ambient seismic noise field structure according to the data of the seismic gradient system and a passive noise interferometry diagram, where microseisms from the underground sources are used as the seismic signal source. It is shown that the use of noise interferometry and passive seismic gradient system allows using the synchronous microseism recordings in a small number of points for passive medium sensing, and leads to the restoration of unknown energy parameters of the seismic field of underground sources.

关键词： gradient system passive seismic Tien Shan geodynamics

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Leaf area index estimated by direct, semi-direct, and indirect methods in European beech and sycamore maple stands

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Journal of Forestry Research 2020年第3期31卷 827-836页

作者： Jakub Cerny pavel Haninec Radek Pokorny The Forestry and Game Management Research Institute Research Station at OpocnoNa Olive 55051773 OpocnoCzech Republic The Department of Silviculture and Forest Establishment Faculty of Forestry and Wood TechnologyMendel UniversityZemedelska 361300 BrnoCzech Republic

Leaf area index(LAI)is one of the most important characteristics of forest stands that affects the fundamentals of tree physiological processes,biomass production,and mechanical *** LAI results obtained by the semi-direct and indirect methods(the needle technique and an LAI-2000 PCA)in three European beech(Fagus sylvatica L.)stands and one sycamore maple(Acer pseudoplatanus L.)stand were compared with LAI estimated by litter traps during the 2013 growing *** LAI was estimated using an LAI-2000 PCA which showed similar trends among the stands and strongly corresponded to phenological phases of deciduous stands in Europe,with the fastest rate of leaf area increment occurring during the first month following bud *** the growing season,maximum stand LAI value was on June 19th and reached 4.5–5.1,and 4.0 in the beech and maple stands,*** needle technique significantly underestimated(p05)LAI on average by 15.1%and 5.8%in the beech and maple stands,*** methods for LAI estimation at the stand level could be applicable in deciduous forest stands(beech,maple)with similar site and stand ***,calibration by direct method is necessary to obtain the required precision.

关键词： Leaf area index Specific leaf area Litter trap Needle technique LAI-2000 PCA

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