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nonstationary laser-supported ionization wave in layer of porous substance with subcritical density

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Matter and Radiation at Extremes 2024年第1期9卷 58-70页

作者： S.Yu Gus’kov R.A.Yakhin P.n.Lebedev Physical Institute of Russian Academy of Sciences Leninskii Prospect 53Moscow 119991Russia

A time-dependent analytical solution is found for the velocity of a plane ionization wave generated under nanosecond laser pulse action on the surface of a flat layer of low-Z porous substance with density less than the critical density of the produced *** corrections for the two-dimensional nature of the problem when a laser beam of finite radius interacts with a flat target,this solution is in quantitative agreement with measurements of ionization wave velocity in various *** solution compared with experimental data covering wide ranges of performance conditions,namely,(3-8)×10^(14)W cm^(−2)for laser pulse intensity,0.3-3 ns for pulse duration,0.35-0.53μm for laser wavelength,100-1000μm for laser beam radius,380-950μm for layer thickness,4.5-12 mg cm^(−3)for average density of porous substance,and 1-25μm for average pore *** parameters of the laser beam that ensure the generation of a plane ionization wave in a layer of subcritical porous matter are determined for the problem statements and are found to meet the requirements of practical applications.

关键词： laser pulse porous

On non-normal Arc-Transitive 4-Valent Dihedrants

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Acta Mathematica Sinica,English Series 2010年第8期26卷 1485-1498页

作者： István kovCS Botjan KUZMAn Aleksander MALnI FAMnIT University of Primorska PeF University of Ljubljana IMFM University of Ljubljana

Let X be a connected non-normal 4-valent arc-transitive Cayley graph on a dihedral group Dn such that X is bipartite, with the two bipartition sets being the two orbits of the cyclic subgroup within Dn. It is shown that X is isomorphic either to the lexicographic product Cn[2K1] with n 〉 4 even, or to one of the five sporadic graphs on 10, 14, 26, 28 and 30 vertices, respectively.

关键词： Cayley graph arc transitivity dihedral group

Isomorphisms of Cubic Cayley Graphs on Dihedral Groups and Sparse Circulant Matrices

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Acta Mathematica Sinica,English Series 2023年第4期39卷 618-632页

作者： Istvan kovACS UP IAM&FAMnIT University of PrimorskaMuzejski trg 26000 KoperSlovenia

We show that,up to isomorphism,there is a unique non-CI connected cubic Cayley graph on the dihedral group of order 2n for each even number n≥*** answers in the negative the question of Li whether all connected cubic Cayley graphs are CI-graphs(Discrete Math.,256,301-334(2002)).As an application,a formula is derived for the number of isomorphism classes of connected cubic Cayley graphs on dihedral groups,which generalises the earlier formula of Huang et *** with the particular case when n is a prime(Acta ***.,***.,33,996-1011(2017)).As another application,a short proof is also given for a result on sparse circulant matrices obtained by Wiedemann and Zieve(arXiv preprint,(2007)).

关键词： Cayley graph graph isomorphism dihedral group circulant matrix

Enabling Technologies for Autonomous Robotic Systems in Manufacturing

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Transactions of nanjing University of Aeronautics and Astronautics 2024年第4期41卷 403-431页

作者： ERDŐS Gábor ABAI Kristóf BEREGI Richárd CSEMPESZ János CSERTEG Tamás GODÓGábor HAJÓS Mátyás HÁY Borbála HORVÁTH Dániel HORVÁTH Gergely JUnIKIÁdám KEMÉnY Zsolt kovÁCS András nACSA János PAnITI Imre PEDOnE Gianfranco TAKÁCS Emma TIPARY Bence ZAHORÁn László VÁnCZA József Institute for Computer Science and Control Hungarian Research Network(HUN-REN SZTAKI)BudapestHungary Department of Manufacturing Science and Technology Budapest University of Technology and Economics(BME)BudapestHungary EPIC InnoLabs nonprofit Ltd. BudapestHungary Eötvös Loránd University(ELTE) BudapestHungary

Research of autonomous manufacturing systems is motivated both by the new technical possibilities of cyber-physical systems and by the practical needs of the *** operation in semi-structured industrial environments can now be supported by advanced sensor technologies,digital twins,artificial intelligence and novel communication *** enable real-time monitoring of production processes,situation recognition and prediction,automated and adaptive(re)planning,teamwork and performance improvement by *** paper summarizes the main requirements towards autonomous industrial robotics and suggests a generic workflow for realizing such *** case studies will be presented from recent practice at HUn-REn SZTAKI in a broad range of domains such as assembly,welding,grinding,picking and placing,and *** various solutions have in common that they use a generic digital twin concept as their *** making general recommendations for realizing autonomous robotic solutions in the industry,open issues for future research will be discussed.

关键词： industrial robotics autonomy digital twin enabling technology

Automated tree detection and crown delineation using airborne laser scanner data in heterogeneous East-Central Europe forest with different species mix

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Journal of Forestry Research 2017年第5期28卷 1049-1059页

作者： Róbert Smreek Ivan Sakov Zuzana Michnová Ján Tuek Department of Forest Management and Geodesy Technical University in Zvolen Department of Forest Policy Economics and Forest ManagementNational Forest Centre-Forest Research Institute Zvolen

Identifying tree locations is a basic step in the derivation of other tree parameters using remote sensing techniques, particularly when using airborne laser scanning. There are several techniques for identifying tree positions. In this paper, we present a raster-based method for determining tree position and delineating crown coverage. We collected data from nine research plots that supported different mixes of species. We applied a raster-based method to raster layers with six different spatial resolutions and used terrestrial measurement data as reference data. Tree identification at a spatial resolution of 1.5 m was demonstrated to be the most accurate, with an average identification ratio (IR) of 95% and average detection ratio of 68% being observed. At a higher spatial resolution of 0.5 m, IR was overestimated by more than 600%. At a lower spatial resolution of 3 m, IR was underestimated at less than 44% of terrestrial measurements. The inventory process was timed to enable evaluation of the time efficiency of automatic methods.

关键词： Airborne laser scanning East-Central Europe Individual tree Mixed forest Tree crown delineation

A General Version of the Retract Method for Discrete Equations

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Acta Mathematica Sinica,English Series 2007年第2期23卷 341-348页

作者： Josef DIBLíK Irena RzIkov Miroslava RZIkov Department of Mathematics Faculty of Electrical Engineering and CommunicationBrno University of TechnologyTechnická 8616 00 BrnoCzech Republic Department of Applied Mathematics Faculty of ScienceCilina UniversityHurbanova 15010 26 CilinaSlovak Republic

We study a problem concerning the compulsory behavior of the solutions of systems of discrete equations u（k ＋ 1） = F（k, u（k））, k ∈ n（a） = {a, a ＋ 1, a ＋ 2 }, a ∈ n,n= {0, 1,... } and F ： n（a） × R^n→R^n. A general principle for the existence of at least one solution with graph staying for every k ∈ n（a） in a previously prescribed domain is formulated. Such solutions are defined by means of the corresponding initial data and their existence is proved by means of retract type approach. For the development of this approach a notion of egress type points lying on the defined boundary of a given domain and with respect to the system considered is utilized. Unlike previous investigations, the boundary can contain points which are not points of egress type, too. Examples are inserted to illustrate the obtained result.

关键词： discrete equation consequent point retract

Role of forests in headwater control with changing environment and society

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International Soil and Water Conservation Research 2021年第1期9卷 143-157页

作者： Josef Krecek Jana nováková Ladislav Palán Eva Pazourková Evzen Stuchlík Department of Hydrology Czech Technical University in PragueThákurova 7CZ-16629Prague 6Czech Republic Independent Botanist Na Vrcholu 4CZ-13000PragueCzech Republic AOn Impact Forecasting Václavskénáměstí19CZ-11000PragueCzech Republic Institute of Hydrobiology Biology CentreCzech Academy of SciencesNa Sádkách 7CZ-37005(C)eskéBudějoviceCzech Republic

Forest practices in headwater catchments are related to environmental and social *** aim of this study is to analyse the changing protective functions of forests in the upper plain of the Jizera Mts.(north Bohemia,Czech Republic)since the second half of the 19th *** time,forests have gradually changed from native stands to spruce plantations(Picea abies),introducing exotic conifers(more resistant to air pollution),and,recently,back to more diverse mixed *** priority in pro-tective forest functions there shifted from flood protection to integrated control of water resources(quantity and quality).In the 1980s,forest-water interactions were degraded by consequences of extreme acid atmospheric deposition,forest die-back,and extensive *** the Jizerka catchment,first signs of recovery were observed in the early *** waters there are still affected by prolonged *** reconstruction of stream water chemistry at Jizerka follows the drop of the acid deposition in some 5 years,the revival of stream biota takes 10-15 *** 2071-2100,the pro-jected climate change shows rising annual air temperatures by 3.0-4.6℃,decreasing water yield by 65-123 mm,60%drop in'minimum residual discharge',and 20-30%rise in ***,these projected environmental changes cannot substantially decline the high potential in water resource recharge,or,start reverse processes in recent recovery from acidification and radically affect the exis-tence of planned mixed forests in the upper plain of the Jizera Mts.

关键词： Headwater catchment Forest functions Water resource recharge Acid atmospheric deposition Climate change

Efficiency of local minima and GLM techniques in sinkhole extraction from a LiDAR-based terrain model

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International Journal of Digital Earth 2019年第9期12卷 1067-1082页

作者： Péter Enyedi Melinda Pap Zoltán kovács László Takács-Szilágyi Szilárd Szabó a Department of Physical Geography and Geoinformatics University of DebrecenDebrecenHungary Internet of Things Research Institute Eszterházy Károly University of Applied SciencesEgerHungary

The aim of this paper was to study reliable automated delineationpossibilities of karst sinkholes using a LiDAR-based digital terrain model(DTM) with pixel-based classifications. We applied two approaches toextract sinkholes: (1) general linear modeling (GLM) with morphometricindices derived from DTM;(2) and a local minima-based delineationusing only LiDAR DTM as the input layer. The outcome of the localminima was significantly different from the reference ones but found allthe sinkholes without previous knowledge of the area. The GLM-basedoutcome did not differ statistically from the reference. Results showedthat these approaches were efficient in detecting sinkholes based onLIDAR derivatives, and can be used for risk assessment and hazardpreparedness in karst areas: GLM had an overall accuracy of 89.5% andlocal minima had an accuracy of 92.3%;both methods identifiedsinkholes but also had commission errors, identifying depressions assinkholes.

关键词： Karst mapping sinkhole identification general linear model statistical evaluation sink fill

Water in the upper mantle and deep crust of eastern China: concentration, distribution and implications

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national Science Review 2019年第1期6卷 125-144页

作者： Qun-Ke Xia Jia Liu István kovács Yan-Tao Hao Pei Li Xiao-Zhi Yang Huan Chen Ying-Ming Sheng School of Earth Sciences Zhejiang University CAS Key Laboratory of Crust-Mantle Materials and Environments University of Science and Technology of China Hungarian Geological and Geophysical Institute 4. School of Earth Sciences and Engineering Nanjing University

Understanding the concentration and distribution of water in the Earth’s mantle plays a substantial role in studying its chemical, physical and dynamic processes. After a decade of research, a comprehensive dataset of water content in upper-mantle samples has been built for eastern China, which is now the only place with water-content data from such diverse types of natural samples, and provides an integrated picture of the water content and its distribution in the upper mantle at a continental scale. The main findings include the following:(i) the temporal heterogeneity of the water content in the lithospheric mantle from early Cretaceous(～120 Ma) to Cenozoic(nnected with the stability of the north China Craton(from its destruction to its consolidation);(ii) the heterogeneous water content in the Cenozoic lithospheric mantle beneath different blocks of eastern China was not only inherited from tectonic settings from which they came, but was also affected later by geological processes they experienced;(iii) the distinct water content between the lowermost crust and lithospheric mantle of eastern China and its induced rheological contrast at the base of the crust indicate that the continental crust–mantle boundary could behave either in a coupled or decoupled manner beneath different areas and/or at different stages;(iv) the alkali basalts of eastern China demonstrate a heterogeneous distribution of water content in the mantle;local and regional comparisons of the water content between the lithospheric mantle and basalts’ source indicate that the Cenozoic alkali basalts in eastern China were not sourced from the lithospheric ***, the inferred high water contents in the mantle sources suggest that the Cenozoic eastern China basalts were likely sourced from the mantle transition zone(MTZ); and(v) both oceanic and continental crusts may carry a certain amount of water back into the deep mantle of eastern China by plate *** re

关键词： water upper mantle and deep crust continental stability basalt genesis eastern China