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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

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

Synthesis of ultrathin rhenium disulfide nanoribbons using nano test tubes

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nano Research 2022年第2期15卷 1282-1287页

作者： Luke T.norman Johannes Biskupek Graham A.Ranee Craig T.Stoppiello Ute Kaiser andrei n.Khlobystov School of Chemistry University of NottinghamNottinghamNG72RDUK Central Facility for Electron Microscopy Ulm UniversityAlbert Einstein-Allee 11Ulm 89081Germany nanoscale and Microscale Research Centre University of NottinghamNottinghamNG72RDUK

The synthesis of ultrathin rhenium disulfide(ReS_(2))nanoribbons within single-walled carbon nanotubes(SWnTs)has been *** decacarbonyl complex is encapsulated into the SWnTs to provide a source of confined rhenium atoms,which readily react with iodine to form discrete nm-sized clusters of rhenium iodide[Re_(6)l_(14)]^(2-) embedded in the *** final step of the synthesis is accomplished by admitting hydrogen sulfide gas into nano test tubes,yielding twisted nanoribbons of rhenium disulfide encapsulated in carbon nanotubes,ReS_(2)@*** width,structure,and composition of rhenium disulfide nanoribbons are strictly controlled by the extreme confinement of the host-SWnT.A holistic analytical approach combining complementary imaging and analysis methods is used at each synthetic step to elucidate the structure and composition of the guest material and reveal the role of the SWnT contributing towards the electronic interactions with encapsulated inorganic *** ReS_(2) nanoribbons are expected to retain the electronic properties of the bulk material,such as direct bandgap,the low dimensional form of this material can be of interest for use in nanoscale electronic devices.

关键词： nanotubes nanoribbons rhenium confinement microscopy spectroscopy

Modeling electronic and optical properties of Ⅲ–Ⅴ quantum dots-selected recent developments

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Light(Science & Applications) 2022年第1期11卷 13-26页

作者： Alexander Mittelstädt andrei Schliwa Petr Klenovský Institute for Solid State Physics Technical University of BerlinHardenbergstrasse 36D-10623 BerlinGermany Department of Condensed Matter Physics Faculty of ScienceMasaryk UniversityKotlářská267/261137 BrnoCzech Republic Czech Metrology Institute Okružní3163800 BrnoCzech Republic

Electronic properties of selected quantum dot(QD)systems are surveyed based on the multi-band k·p method,which we benchmark by direct comparison to the empirical tight-binding algorithm,and we also discuss the newly developed"linear combination of quantum dot orbitals"***,we focus on two major complexes:First,the role of antimony incorporation in InGaAs/GaAs submonolayer QDs and In1−xGax AsySb1−y/GaP QDs,and second,the theory of QD-based quantum cascade lasers and the related prospect of room temperature lasing.

关键词： quantum optical lasing

Mucosal healing effect of mesalazine granules in naproxen-induced small bowel enteropathy

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World Journal of Gastroenterology 2013年第6期19卷 889-896页

作者： István Rácz Milán Szalai Valéria kovács Henriett Regczi Gyngyi Kiss Zoltán Horváth Department of Gastroenterology Petz Aladár County and Teaching Hospital Department of Mathematics and Computational Sciences Széchenyi István University

AIM:To investigate the effect of mesalazine granules on small intestinal injury induced by naproxen using capsule endoscopy (CE).METHODS:This was a single center,non-randomized,open-label,uncontrolled pilot study,using the PillCam SB CE system with RAPID 5 *** Lewis Index Score (LIS) for small bowel injury was investigated to evaluate the severity of mucosal *** patients with at least one month history of daily naproxen use of 1000 mg and proton pump inhibitor co-therapy were *** with a minimum LIS of 135 were eligible to enter the 4-wk treatment phase of the *** this treatment period,3 × 1000 mg/d mesalazine granules were added to ongoing therapies of 1000 mg/d naproxen and 20 mg/d *** the end of the 4-wk combined treatment period,a second small bowel CE was performed to re-evaluate the enteropathy according to the LIS *** primary objective of this study was to assess the mucosal changes after 4 wk of mesalazine ***:A total of 18 patients (16 females),ranging in age from 46 to 78 years (mean age 60.3 years) were screened,all had been taking 1000 mg/d naproxen for at least one *** patients were excluded from the mesalazine therapeutic phase of the study for the following reasons:the screening CE showed normal small bowel mucosa or only insignificant damages (LIS n five patients,the screening esophagogastroduodenoscopy revealed gastric ulcer in one patient,capsule technical failure and incomplete CE due to poor small bowel cleanliness in two *** patients (9 female,mean age 56.2 years) whose initial LIS reached mild and moderate-to-severe enteropathy grades (between 135 and 790 and ≥ 790) entered the 4-wk therapeutic phase and a repeat CE was *** comparing the change in LIS from baseline to end of treatment in all patients,a marked decrease was seen (mean LIS:1236.4 ± 821.9 vs 925.2 ± 543.4,P=0.271).Moreover,a significant difference between pre-and post-t

关键词： nonsteroidal anti-inflammatory drug Small bowel enteropathy Mesalazine granules Mucosal healing Capsule endoscopy

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