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Sufficient Conditions for Maximally Edge-connected and Super-edge-connected Digraphs Depending on the Size

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Acta Mathematica Sinica,English Series 2019年第12期35卷 1861-1870页

作者： Sebastian MILZ Lutz VOLKMANN lehrstuhl ⅱ für mathematik RWTH Aachen University

Let D be a finite and simple digraph with vertex set V(D).The minimum degreeδof a digraph D is defined as the minimum value of its out-degrees and its *** D is a digraph with minimum degreeδand edge-connectivity λ,then λ≤δ.A digraph is maximally edge-connected ifλ=δ.A digraph is called super-edge-connected if every minimum edge-cut consists of edges incident to or from a vertex of minimum *** this note we show that a digraph is maximally edge-connected or super-edge-connected if the number of arcs is large enough.

关键词： Digraphs edge-connectivity maximally edge-connected digraphs super-edge-connected digraphs

AN AUGMENTED BV SETTING fOr fEEDBACK SWITCHING CONTrOL

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Journal of Systems Science & Complexity 2010年第3期23卷 456-466页

作者： falk M.HANTE Günter LEUGErING Thomas I.SEIDMAN Department mathematik Lehrstuhl für Angewandte Mathematik ⅡUniversitt Erlangen-Nürnberg Department of Mathematics and Statistics University of Maryland Baltimore County

This paper considers dynamical systems under feedback with control actions limited *** authors wish to understand the closed-loop systems as approximating multi-scale problemsin which the implementation of switching merely acts on a fast *** hybrid dynamicalsystems are extensively studied in the literature,but not much so far for feedback with partial *** becomes in particular relevant when the dynamical systems are governed by partialdifferential *** authors introduce an augmented BV setting which permits recognition ofcertain fast scale effects and give a corresponding well-posedness result for observations with such *** an application for this setting,the authors show existence of solutions for systemsof semilinear hyperbolic equations under such feedback with pointwise observations.

关键词： feedback functions of bounded variation hybrid dynamical systems partial state observation switching control.

Absorbing Boundary Conditions for Hyperbolic Systems

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Numerical Mathematics(Theory,Methods and Applications) 2010年第3期3卷 295-337页

作者： Matthias Ehrhardt lehrstuhl für Angewandte mathematik und Numerische Analysis Fachbereich C Mathematik und NaturwissenschaftenBergische Universitt WuppertalGaufβstrasse 2042119 WuppertalGermany

This paper deals with absorbing boundary conditions for hyperbolic systems in one and two space *** prove the strict well-posedness of the resulting initial boundary value problem in *** we establish the GKS-stability of the corresponding Lax-Wendroff-type finite difference ***,we have to extend the classical proofs,since the(discretized) absorbing boundary conditions do not fit the standard form of boundary conditions for hyperbolic systems.

关键词： Absorbing boundary conditions hyperbolic system Engquist and Majda approach,strict well-posedness GKS-stability.

Total restrained Bondage in Graphs

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Acta Mathematica Sinica,English Series 2013年第6期29卷 1033-1042页

作者： Nader JAfArI rAD roslan HASNI Joanna rACZEK Lutz VOLKMANN Department of Mathematics Shahrood University of Technology Department of Mathematics Faculty of Science and Technology University Malaysia Terengganu Department of Mathematics Gdansk University of Technology lehrstuhl II fr mathematik RWTH Aachen University

A subset S of vertices of a graph G with no isolated vertex is a total restrained dominating set if every vertex is adjacent to a vertex in S and every vertex in V （G） S is also adjacent to a vertex in V （G） S. The total restrained domination number of G is the minimum cardinality of a total restrained dominating set of G. In this paper we initiate the study of total restrained bondage in graphs. The total restrained bondage number in a graph G with no isolated vertex, is the minimum cardinality of a subset of edges E such that G E has no isolated vertex and the total restrained domination number of G E is greater than the total restrained domination number of G. We obtain several properties, exact values and bounds for the total restrained bondage number of a graph.

关键词： Domination total restrained domination bondage

A New Convergent Explicit Tree-Grid Method for HJB Equations in One Space Dimension

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Numerical Mathematics(Theory,Methods and Applications) 2018年第1期11卷 1-29页

作者： Igor Kossaczky Matthias Ehrhardt Michael Gunther lehrstuhl fur Angewandte mathematik und Numerische Analysis Fakultat fur Mathematik und NaturwissenschaftenBergische Universitat WuppertalGaußstrasse 2042119 WuppertalGermany

In this work we introduce a new unconditionally convergent explicit Tree-Grid Method for solving stochastic control problems with one space and one time dimension or equivalently,the corresponding Hamilton-Jacobi-Bellman *** prove the convergence of the method and outline the relationships to other numerical *** case of vanishing diffusion is treated by introducing an artificial diffusion *** illustrate the superiority of our method to the standardly used implicit finite difference method on two numerical examples from finance.

关键词： Tree-Grid Method Hamilton-Jacobi-Bellman equation Stochastic control problem

DONSKEr'S WEAK INVArIANCE PrINCIPLE WITH rATES fOr C[0,1] - VALUED, DEPENDENT rANDOM - fUNCTIONS

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Analysis in Theory and Applications 1986年第4期 55-77页

作者： P.L.Butzer H.J.W.Kirschfink lehrstuhl lehrstuhl A für mathematik Aachen University of Technology 51 Aachen West Germany A für mathematik Aachen University of Technology 51 Aachen West Germany

Ⅰ. Introduction This paper is concerned with the weak invariance principle,namely with the weak convergence of the distribution of the randompolygonal lines

关键词： DEPENDENT rANDOM DONSKEr’S WEAK INVArIANCE PrINCIPLE WITH rATES fOr C[0,1 fUNCTIONS VALUED

A simulation study on spatial and time resolution for a cost-effective positron emission particle tracking system

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Particuology 2024年第5期88卷 312-322页

作者： Josephine Oppotsch Matthias Steinke Miriam fritsch fritz-Herbert Heinsius Thomas Held Nikoline Hilse Viktor Scherer Ulrich Wiedner ruhr-Universität Bochum Institut für Experimentalphysik I44801 BochumGermany ruhr-Universität Bochum Lehrstuhl für Energieanlagen und Energieprozesstechnik44801 BochumGermany

This work is the second part of a simulation study investigating the processing of densely packed and moving granular assemblies by positron emission particle tracking (PEPT).Since medical positron emission tomography (PET) scanners commonly used for PEPT are very expensive,a PET-like detector system based on cost-effective organic plastic scintillator bars is being developed and tested for its *** this context,the spatial resolution of a resting positron source,a source moving on a freely designed model path,and a particle motion given by a discrete element method (DEM) simulation is studied using Monte Carlo simulations and the software toolkit *** not only extended the simulation and reconstruction to a moving source but also significantly improved the spatial resolution compared to previous work by adding oversampling and iteration to the reconstruction ***,in the case of a source following a trajectory developed from DEM simulations,a very good resolution of about 1 mm in all three directions and an average 3D deviation between simulated and reconstructed events of 2.3 mm could be ***,the resolution for realistic particle motion within the generic grate system (which is the test rig for further experimental studies) is well below the smallest particle *** simulation of the dependence of the reconstruction accuracy on tracer particle location revealed a nearly constant efficiency within the entire detector system,which demonstrates that boundary effects can be neglected.

关键词： Positron emission particle tracking Monte Carlo method Time-of-flight Plastic scintillators Silicon photomultipliers(SiPMs)

A simulation study for a cost-effective PET-like detector system intended to track particles in granular assemblies

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Particuology 2024年第1期84卷 117-125页

作者： Josephine Oppotsch Antonios Athanassiadis Miriam fritsch fritz-Herbert Heinsius Thomas Held Nikoline Hilse Viktor Scherer Matthias Steinke Ulrich Wiedner ruhr-Universität Bochum Institut für Experimentalphysik I44801 BochumGermany ruhr-Universität Bochum Lehrstuhl für Energieanlagen und Energieprozesstechnik44801 BochumGermany

Since many industrial applications rely on the processing of densely packed and moving granular ma-terial,obtaining bulk internal information on the particle movement inside the reactors is of great *** information can be delivered by Positron Emission Particle Tracking(PEPT).By marking pellets with a positron-emitting radioisotope,the position of these tracer particles can be determined via the time-of-flight differences of the emitted gamma-ray *** current paper proposes a PET-like detector system based on cost-effective organic plastic scintillators instead of the more common but expensive inorganic *** system is currently under construction and was tested for its resolution and efficiency in this simulation *** Monte Carlo simulations and the software toolkit Geant4,three different geometries(an empty glass box,a generic grate system,and a cubic box of 1 m3 completely filled with pellets)were investigated,leading to a spatial resolution in the millimeter range and an efficiency,defined as the ratio of reconstructed decay locations to simulated decays,of 2.7%,1.4%,and 0.3%.

关键词： Positron emission particle tracking Geant4 Monte Carlo method Time-of-flight Plastic scintillators Silicon photomultipliers(SiPMs)

Domain Structure of the Selenocysteine-specific Translation factor SelB in Prokaryotes

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Biomedical and Environmental Sciences 1997年第2期10卷 125-128页

作者： AUGUST B■CK rOLf HILGENfELD PETEr TOrMAY rEINHArD WILTING, AND MATTHIAS KrOMAYEr (lehrstuhl fur Mikrobiologie der Universitat uüunchen, MiriaWard-Strasse 1a, D-80638 Munchen, Germany Institut fur olekulare Biotechnologie, Beutenbergtrasse 11,D-0770 lehrstuhl für Mikrobiologie Universität München Germany.

Translation factor SelB is the key component for the specific decoding of UGA codons with selenocysteine at the ribosome. SelB binds selenocysteyl-trNASec, guanine nucleotides and a secondary structure of the selenoprotein mrNA following the UGA at the 3' side. A comparison of the amino acid sequences of SelB species from E. coli,Desulfomicrobium baculatum, Clostridium thermoaceticum and Haemophilus influenzae showed that the proteins consist of at least four structural domains from which the Nterminal three are well conserved and share homology with elongation factor Tu whereas the C-terminal one is more variable and displays no similarity to any protein known. With the aid of the coordinates of Ef-Tu the N-terminal part has been modelled into a 3D structure which exhibits intriguing features concerning its interaction with guanine nucleotides and other components of the translational apparatus. Cloning and expression of fragments of SelB and biochemical analysis of the purified truncated proteins showed that the C-terminal 19 kDa protein fragment is able to specifically bind to the selenoprotein mrNA. SelB, thus, is a translation factor functionally homologous to Ef-Tu hooked up to the mrNA with its C-terminal end. The formation by SelB of a quaternary complex in vivo has been proven by overexpression of truncated genes of SelB and by demonstration that fragments comprising the mrNA or the trNA binding domain inhibit selenocysteine insertion

关键词： mrNA Ef Ts trNA Domain Structure of the Selenocysteine-specific Translation factor SelB in Prokaryotes Nature