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Full-Text Articles in Physical Sciences and Mathematics

Eigenvalue Analysis Of A Block Red-Black Gauss–Seidel Preconditioner Applied To The Hermite Collocation Discretization Of Poisson's Equation, Stephen Brill, George Pinder Mar 2012

Eigenvalue Analysis Of A Block Red-Black Gauss–Seidel Preconditioner Applied To The Hermite Collocation Discretization Of Poisson's Equation, Stephen Brill, George Pinder

Stephen H. Brill

This article is concerned with the numerical solution of Poisson's equation with Dirichlet boundary conditions, defined on the unit square, discretized by Hermite collocation with uniform mesh. In [1], it was demonstrated that the Bi-CGSTAB method of van der Vorst [2] with block Red-Black Gauss–Seidel (RBGS) preconditioner is an efficient method to solve this problem. In this article, we derive analytic formulae for the eigenvalues that control the rate at which the Bi-CGSTAB/RBGS method converges. These formulae, which depend upon the location of the collocation points, can be utilized to determine where the collocation points should be placed in order …

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Optimal Hermite Collocation Applied To A One-Dimensional Convection-Diffusion Equation Using An Adaptive Hybrid Optimization Algorithm, Karen Ricciardi, Stephen Brill Mar 2012

Optimal Hermite Collocation Applied To A One-Dimensional Convection-Diffusion Equation Using An Adaptive Hybrid Optimization Algorithm, Karen Ricciardi, Stephen Brill

Stephen H. Brill

Purpose – The Hermite collocation method of discretization can be used to determine highly accurate solutions to the steady-state one-dimensional convection-diffusion equation (which can be used to model the transport of contaminants dissolved in groundwater). This accuracy is dependent upon sufficient refinement of the finite-element mesh as well as applying upstream or downstream weighting to the convective term through the determination of collocation locations which meet specified constraints. Owing to an increase in computational intensity of the application of the method of collocation associated with increases in the mesh refinement, minimal mesh refinement is sought. Very often this optimization problem …

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Analysis Of A Block Red-Black Preconditioner Applied To The Hermite Collocation Discretization Of A Model Parabolic Equation, Stephen Brill, George Pinder Mar 2012

Analysis Of A Block Red-Black Preconditioner Applied To The Hermite Collocation Discretization Of A Model Parabolic Equation, Stephen Brill, George Pinder

Stephen H. Brill

We are concerned with the numerical solution of a model parabolic partial differential equation (PDE) in two spatial dimensions, discretized by Hermite collocation. In order to efficiently solve the resulting systems of linear algebraic equations, we choose the Bi-CGSTAB method of van der Vorst (1992) with block Red-Black Gauss-Seidel (RBGS) preconditioner. In this article, we give analytic formulae for the eigenvalues that control the rate at which Bi-CGSTAB/RBGS converges. These formulae, which depend on the location of the collocation points, can be utilized to determine where the collocation points should be placed in order to make the Bi-CGSTAB/RBGS method converge …

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Labeling Matched Sums With A Condition At Distance Two, Sarah Spence Adams, Denise Troxell Mar 2012

Labeling Matched Sums With A Condition At Distance Two, Sarah Spence Adams, Denise Troxell

Sarah Spence Adams

An L(2,1)-labeling of a graph G is a function f:V(G)→{0,1,…,k} such that |f(x)−f(y)|≥2 if x and y are adjacent vertices, and |f(x)−f(y)|≥1 if x and y are at distance 2. Such labelings were introduced as a way of modeling the assignment of frequencies to transmitters operating in close proximity within a communications network. The lambda number of G is the minimum k over all L(2,1)-labelings of G. This paper considers the lambda number of the matched sum of two same-order disjoint graphs, wherein the graphs have been connected by a perfect matching between the two vertex sets. Matched sums have …

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Dynamic Monopolies And Feedback Vertex Sets In Hexagonal Grids, Sarah Spence Adams, Denise Troxell, S. Luke Zinnen Mar 2012

Dynamic Monopolies And Feedback Vertex Sets In Hexagonal Grids, Sarah Spence Adams, Denise Troxell, S. Luke Zinnen

Sarah Spence Adams

In a majority conversion process, the vertices of a graph can be in one of the two states, colored or uncolored, and these states are dynamically updated so that a vertex becomes colored at a certain time period if at least half of its neighbors were in the colored state in the previous time period. A dynamic monopoly is a set of vertices in a graph that when initially colored will eventually cause all vertices in the graph to become colored. This paper establishes a connection between dynamic monopolies and the well-known feedback vertex sets which are sets of vertices …

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A Construction Technique For Generalized Complex Orthogonal Designs And Applications To Wireless Communications, Jennifer Seberry, Sarah Spence Adams, Tadeusz Wysocki Mar 2012

A Construction Technique For Generalized Complex Orthogonal Designs And Applications To Wireless Communications, Jennifer Seberry, Sarah Spence Adams, Tadeusz Wysocki

Sarah Spence Adams

We introduce a construction technique for generalized complex linear processing orthogonal designs, which are p × n matrices X satisfying XHX = fI, where f is a complex quadratic form, I is the identity matrix, and Xhas complex entries. These matrices generalize the familiar notions of orthogonal designs and generalized complex orthogonal designs. We explain the application of these matrices to space–time block coding for multiple-antenna wireless communications. In particular, we discuss the practical strengths of the space–time block codes constructed via our proposed technique.

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Bistability In A Simple Fluid Network Due To Viscosity Contrast, John Geddes, Brian Storey, David Gardner, Russell Carr Mar 2012

Bistability In A Simple Fluid Network Due To Viscosity Contrast, John Geddes, Brian Storey, David Gardner, Russell Carr

Brian Storey

We study the existence of multiple equilibrium states in a simple fluid network using Newtonian fluids and laminar flow. We demonstrate theoretically the presence of hysteresis and bistability, and we confirm these predictions in an experiment using two miscible fluids of different viscosity—sucrose solution and water. Possible applications include blood flow, microfluidics, and other network flows governed by similar principles.

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Noise-Induced Oscillations In An Actively Mode-Locked Laser, Kelly Black, John Geddes Mar 2012

Noise-Induced Oscillations In An Actively Mode-Locked Laser, Kelly Black, John Geddes

John B. Geddes

Oscillations induced by noise are examined for an actively mode-locked laser. Additive noise, proportional noise, and combined noise are considered. Spatial noise is approximated by Hermite expansions and temporal noise is approximated via an approximation of the variance of the random variable using a fourth-order Adams–Bashforth scheme. The approach is verified on a sample problem and used to explore the governing equations for a mode-locked laser. The inclusion of multiplicative noise leads to much wider pulses and much longer intervals between pulses.

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Multiple Equilibrium States In A Micro-Vascular Network, David Gardner, Yiyang Li, Benjamin Small, John Geddes, Russell Carr Mar 2012

Multiple Equilibrium States In A Micro-Vascular Network, David Gardner, Yiyang Li, Benjamin Small, John Geddes, Russell Carr

John B. Geddes

We use a simple model of micro-vascular blood flow to explore conditions that give rise to multiple equilibrium states in a three-node micro-vascular network. The model accounts for two primary rheological effects: the Fåhræus–Lindqvist effect, which describes the apparent viscosity of blood in a vessel, and the plasma skimming effect, which governs the separation of red blood cells at diverging nodes. We show that multiple equilibrium states are possible, and we use our analytical and computational tools to design an experiment for validation.

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Quantifying Factors That Influence Metal Ion Release In Photocaged Complexes Using Zincast Derivatives, Shawn Burdette Mar 2012

Quantifying Factors That Influence Metal Ion Release In Photocaged Complexes Using Zincast Derivatives, Shawn Burdette

Shawn C. Burdette

Two generations of nitrobenzhydrol-based photocages for Zn2+ have been prepared and characterized. The first series includes the tridentate ZinCast-1 utilizes a bis-pyridin-2-ylmethyl-aniline ligand that forms a 5,5-chelate ring upon metal binding. The related photocages ZinCast-2 with a N-[2-(pyridine-2-yl)ethyl]-N-(pyridine-2-ylmethyl)aniline (5,6-chelate ring) and ZinCast-3 with a N,N-bis[2-(pyridine-2-yl)ethyl]aniline (6,6-chelate ring) were synthesized for comparative studies. The complexes formed by the ions Cu2+, Zn2+ and Cd2+ with three ZinCast and their photoproducts (ZinUnc) were interrogated by UV-Vis spectroscopy. The studies indicate that ZinCast-1 forms complexes of the highest stability and ZinCast-3 exhibits the most significant changes in metal affinity upon uncaging. These results suggest …

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On The Coordinated Navigation Of Multiple Independent Disk-Shaped Robots, Cem Serkan Karagöz, H. Isil Bozma, Daniel Koditschek Mar 2012

On The Coordinated Navigation Of Multiple Independent Disk-Shaped Robots, Cem Serkan Karagöz, H. Isil Bozma, Daniel Koditschek

Daniel E Koditschek

This paper addresses the coordinated navigation of multiple independently actuated disk-shaped robots - all placed within the same disk-shaped workspace. Assuming perfect sensing, shared centralized communications and computation, as well as perfect actuation, we encode complete information about the goal, obstacles and workspace boundary using an artificial potential function over the cross product space of the robots’ simultaneous configurations. The closed-loop dynamics governing the motion of each robot take the form of the appropriate projection of the gradient of this function. We show, with some reasonable restrictions on the allowable goal positions, that this function is an essential navigation function …

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Methods To Convert Local Sampling Coordinates Into Geographic Information System/Global Positioning Systems (Gis/Gps)-Compatible Coordinate Systems, Mark Rudnicki, Thomas Meyer Mar 2012

Methods To Convert Local Sampling Coordinates Into Geographic Information System/Global Positioning Systems (Gis/Gps)-Compatible Coordinate Systems, Mark Rudnicki, Thomas Meyer

Mark Rudnicki

Laying out a sampling transect in the field is a common task when researching natural systems and resources. With widespread availability of global navigation satellite systems (GNSS), such as the US global positioning system (GPS), it is becoming more common to resurvey legacy transects to establish them in globally referenced coordinate systems such as geodetic latitude/longitude or planimetric systems such as the Universal Transverse Mercator (UTM) or the State Plane Coordinate System (SPCS). Transforming local coordinates into a globally referenced coordinate system allows (1) disparate legacy surveys to be combined into a common geographic information system (GIS) database, (2) new …

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A High-Resolution, Multi-Channel, Over-Sea-Ice Seismic Reflection Survey Over The Mackay Sea Valley, Granite Harbor, Antarctica, B. Williams, Marvin Speece, Ross Powell Mar 2012

A High-Resolution, Multi-Channel, Over-Sea-Ice Seismic Reflection Survey Over The Mackay Sea Valley, Granite Harbor, Antarctica, B. Williams, Marvin Speece, Ross Powell

M. A Speece

In the austral summer of 2007, 20.5 km of high-resolution over-sea-ice seismic reflection data were collected in the Granite Harbor region of southern McMurdo Sound over the Mackay Sea Valley. The goal of the survey was to image thin pelagic sediment deposited in the Mackay Sea Valley after the Last Glacial Maximum. A generator–injector air gun was lowered beneath the sea ice through holes drilled by an auger drill system. The recording system was a 60 channel snow streamer with vertically oriented gimbaled geophones spaced 25 m apart. Unique problems in the over-sea-ice seismic reflection survey—noise from the ice column …

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Mixing Them Up: Group-Work With Nesb Students, Mark Freeman Mar 2012

Mixing Them Up: Group-Work With Nesb Students, Mark Freeman

Dr Mark Freeman

This paper describes the implementation of a Problem-Based Learning assessment in a postgraduate ICT fundamentals subject. With an entirely international student cohort drawn from 14 countries, many students had never participated in group work. To facilitate student adjustment into the Australian educational environment, and develop understanding of the role and importance of group work, students were educated in group work theory prior to engaging in the group work process. The experiences of both teaching staff and students identified a number of positive outcomes resulting from this approach.

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2011 Scholars And Artists Bibliography, Mark Tebeau Mar 2012

2011 Scholars And Artists Bibliography, Mark Tebeau

Mark Tebeau

This bibliography was created for the annual Friends of the Michael Schwartz Library Scholars and Artists Reception, recognizing scholarly and creative achievements of Cleveland State University faculty, staff and emeriti. Mark Tebeau was the guest speaker

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Electrically Controlled Exchange Bias For Spintronic Applications, Christian Binek, A. Hochstrat, X. Chen, P. Borisov, W. Kleeman, B. Doudin Mar 2012

Electrically Controlled Exchange Bias For Spintronic Applications, Christian Binek, A. Hochstrat, X. Chen, P. Borisov, W. Kleeman, B. Doudin

Christian Binek

Exchange coupling between a magnetoelectric (111)-oriented Cr2O3 single crystal and a CoPt multilayer with perpendicular anisotropy exhibits an exchange bias field proportional to the applied axial electric field. Extrapolation from bulk to thin film magnetoelectric pinning system suggests promising spintronic applications due to coupling between the electric field-controlled magnetization and the magnetization of a neighbor ferromagnetic layer. Pure voltage control of magnetic configurations of tunneling magnetoresistance spin valves is an attractive alternative to current-induced magnetization switching. ©2005 American Institute of Physics

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Freezing Field Dependance Of The Exchange Bias In Uniaxial Fef2-Copt Heterosystems With Perpendicular Anisotropy, Christian Binek Mar 2012

Freezing Field Dependance Of The Exchange Bias In Uniaxial Fef2-Copt Heterosystems With Perpendicular Anisotropy, Christian Binek

Christian Binek

The exchange bias effect is measured for the first time in FeF2–CoPt heterosystems with perpendicular anisotropy. The exchange previous field exhibits a strong dependence on the axial previous freezing field. This behavior is explained in terms of the microscopic spin structure at the interface, which is established on cooling to below TN. We calculate the dependence of the spin structure on the previous freezing field within the framework of an Ising model. It takes into account the Zeeman energy as well as an antiferromagnetic exchange coupling between the adjacent layers at the interface.

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Isothermal Low-Field Tuning Of Exchange Bias In Epitaxial Fe/Cr2o3/Fe, S. Sahoo, T. Mukherjee, K. Belashchenko, Christian Binek Mar 2012

Isothermal Low-Field Tuning Of Exchange Bias In Epitaxial Fe/Cr2o3/Fe, S. Sahoo, T. Mukherjee, K. Belashchenko, Christian Binek

Christian Binek

Moderate dc magnetic fields of less than 1 T allow tuning the exchange bias in an epitaxially grown Fe 10 nm/Cr2O3 2.7 nm/Fe 10 nm trilayer between negative and positive bias fields. Remarkably, this tunable exchange bias is observed at least up to 395 K which exceeds the Néel temperature of bulk Cr2O3 (307 K). The presence of spontaneous exchange bias and the absence of training effects at room temperature suggest the existence of stable interface moments independent of antiferromagnetic long range order in Cr2O3. Furthermore, the coercivity remains constant, independent of the exchange bias field. In contrast, large training …

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Temperature Dependence Of The Training Effect In Exchange Coupled Ferromagnetic Bilayers, S. Polisetty, Sarbeswar Sahoo, A. Berger, Christian Binek Mar 2012

Temperature Dependence Of The Training Effect In Exchange Coupled Ferromagnetic Bilayers, S. Polisetty, Sarbeswar Sahoo, A. Berger, Christian Binek

Christian Binek

The temperature dependence of the training effect is studied in an exchange coupled thin-film bilayer composed of a hard ferromagnetic pinning (CoPtCrB) layer in proximity of a soft ferromagnetic pinned (CoCr) layer. Interlayer exchange shifts the hysteresis loops of the soft layer along the magnetic-field axis. This shift is quantified by the bias field in far reaching analogy to the exchange bias field of conventional antiferromagnetic/ferromagnetic heterostructures. A ferromagnetic domain state induced in the hard layer experiences aging very similar to the training behavior of the antiferromagnetic domain state in conventional exchange bias systems. Training originates from changes in the …

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Dilution-Induced Enhancement Of The Blocking Temperature In Exchange-Bias Heterosystems, Xi Chen, Christian Binek, A. Hochstrat, W. Kleeman Mar 2012

Dilution-Induced Enhancement Of The Blocking Temperature In Exchange-Bias Heterosystems, Xi Chen, Christian Binek, A. Hochstrat, W. Kleeman

Christian Binek

The temperature dependence of the exchange bias field is investigated by superconducting quantum interference device magnetometry in Fe1-xZnxF2(110)/Fe14 nm/Ag35 nm, x=0.4. Its blocking temperature exhibits a significant enhancement with respect to the global ordering temperature TN=46.9 K, of the bulk antiferromagnet Fe0.6Zn0.4F2. The enhancement is attributed to fluctuations of the diamagnetic dilution which creates clusters on all length scales having a Zn dilution of 0<~x<~1. While the infinite clusters give rise to the well-known Griffiths phase, finite clusters also provoke a local enhancement of the exchange bias. The temperature dependence of the integral exchange bias effect is modeled by averaging all local contributions of the antiferromagnetic surface magnetization which exhibit a surface critical behavior.

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Magnetic Relaxation Phenomena In The Superspin-Glass System [Co80Fe20/Al2O3]10, S. Sahoo, O. Petracic, Christian Binek, W. Kleemann, J. B. Sousa, S. Cardoso, P. P. Freitas Mar 2012

Magnetic Relaxation Phenomena In The Superspin-Glass System [Co80Fe20/Al2O3]10, S. Sahoo, O. Petracic, Christian Binek, W. Kleemann, J. B. Sousa, S. Cardoso, P. P. Freitas

Christian Binek

Relaxation and temperature cycles of thermoremanent magnetization, MTRM, in the superspin-glass phase of [Co80Fe20 (0.9 nm)/Al2O3 (3 nm)] 10 have been investigated. The relaxation of MTRM exhibits ageing phenomena. In negative temperature cycles for temperature steps larger than 1 K the magnetic state is retrieved (memory effect) on returning to the measurement temperature. This property is independent of the application of a field step during intermediate cooling. In positive temperature cycles the relaxation is suppressed after temporary heating. The observations are discussed in the light of both the droplet and the hierarchical picture.

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Metamagnetic Domains And Dynamic Fluctuations In Febr2, O. Petracic, Christian Binek, W. Kleeman Mar 2012

Metamagnetic Domains And Dynamic Fluctuations In Febr2, O. Petracic, Christian Binek, W. Kleeman

Christian Binek

The mixed phase and the regime of non-critical fluctuations of the magnetic phase diagram of FeBr2 is investigated by SQUID susceptometry and light diffraction techniques. The experiments seem to evidence instability of the tricritical point as conjectured recently. The observation of stripe domains and light diffraction below and above Tm = 4.6 K and the virtual continuation of the phase transition line to above Tm are in agreement with the occurrence of a critical endpoint at Tm and of a bicritical endpoint at T > Tm. ©1997 American Institute of Physics.

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Quenching Of The Exchange Bias Training In Fe/Cr2o3/Fe Trilayer, S. Sahoo, Christian Binek Mar 2012

Quenching Of The Exchange Bias Training In Fe/Cr2o3/Fe Trilayer, S. Sahoo, Christian Binek

Christian Binek

Exchange bias (EB) and its associated training effects are studied in an epitaxial Fe(10 nm)/Cr2O3(2.7 nm)/Fe(10 nm) trilayer heterostructure grown by molecular beam epitaxy. The EB decreases linearly with increasing temperature from T = 5 K to T = 50 K. It changes sign and becomes positive within 50 K < T < 200 K, finally changing back to regular EB for T<200K up to the highest measured temperature of T = 395 K. Remarkably, the latter is far above the bulk Néel temperature TN = 307 K. EB training effects occur only at 5 K < T < 50 K. We show …

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Magnetic States Of Discontinuous Co80fe20al2o3 Multilayers, Christian Binek Mar 2012

Magnetic States Of Discontinuous Co80fe20al2o3 Multilayers, Christian Binek

Christian Binek

Discontinuous metal–insulator multilayers [Co80Fe20(t)/Al2O3(3 nm)]n were studied by SQUID magnetometry and AC susceptometry. CoFe forms ferromagnetic particles in the Al2O3 matrix. In this paper, we focus on the field dependence of the AC susceptibility of samples with t=1.3 nm. We find strong evidence for transitions from a superpara- to a superferromagnetic and, finally, to a reentrant superspin glass previous state.

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Nonadiabatic Heat-Capacity Measurements Using A Superconducting Quantum Interference Device Magnetometer, A.I. Kharkovski, Christian Binek, W. Kleeman Mar 2012

Nonadiabatic Heat-Capacity Measurements Using A Superconducting Quantum Interference Device Magnetometer, A.I. Kharkovski, Christian Binek, W. Kleeman

Christian Binek

Nonadiabatic measurements of the heat capacity involving sample-inherent thermometry are proposed. The method is realized with superconducting quantum interference device magnetometry and applied to FeBr2 single crystals by using the magnetization for both thermometry and relaxation calorimetry. When heating with a step pulse of laser light, the magnetization relaxes on a characteristic time scale Ί = RC, where C is the heat capacity and R is the heat resistance between the sample and the bath. R is independently determined from the temperature dependence of the magnetic moment measured with and without stationary light irradiation. ©2000 American Institute of Physics.

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Robust Isothermal Electric Control Of Exchange Bias At Room Temperature, Xi He, Yi Wang, Christian Binek, Peter Dowben Mar 2012

Robust Isothermal Electric Control Of Exchange Bias At Room Temperature, Xi He, Yi Wang, Christian Binek, Peter Dowben

Christian Binek

Voltage-controlled spin electronics is crucial for continued progress in information technology. It aims at reduced power consumption, increased integration density and enhanced functionality where non-volatile memory is combined with highspeed logical processing. Promising spintronic device concepts use the electric control of interface and surface magnetization. From the combination of magnetometry, spin-polarized photoemission spectroscopy, symmetry arguments and first-principles calculations, we show that the (0001) surface of magnetoelectric Cr2O3 has a roughness-insensitive, electrically switchable magnetization. Using a ferromagnetic Pd/Co multilayer deposited on the (0001) surface of a Cr2O3 single crystal, we achieve reversible, room-temperature isothermal switching of the exchange-bias field between positive …

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Domain Wall Relaxation, Creep, Sliding, And Switching In Superferromagnetic Discontinuous Co80Fe20/Al2O3 Multilayers, X. Chen, O. Sichelschmidt, W. Kleeman, Christian Binek, J.B. Sousa, S. Cardoso, P.P. Freitas Mar 2012

Domain Wall Relaxation, Creep, Sliding, And Switching In Superferromagnetic Discontinuous Co80Fe20/Al2O3 Multilayers, X. Chen, O. Sichelschmidt, W. Kleeman, Christian Binek, J.B. Sousa, S. Cardoso, P.P. Freitas

Christian Binek

The ac susceptibility of a superferromagnetic discontinuous multilayer [Co80Fe20(1.4   nm)/ Al2O3(3   nm)]10 is measured as a function of temperature, frequency, and field amplitude and compared to static and dynamic hysteresis loops. Its properties are successfully mapped onto the predicted [T. Nattermann, V. Pokrovsky, and V. M. Vinokur, Phys. Rev. Lett. 87, 197005 (2001).] dynamical phase transitions, which link the relaxation, creep, sliding, and switching regimes of pinned domain walls.

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Electrically Controlled Magnetism, Christian Binek, Xi He, Yi Wang, S. Sahoo Mar 2012

Electrically Controlled Magnetism, Christian Binek, Xi He, Yi Wang, S. Sahoo

Christian Binek

Manipulation of magnetically ordered states by electrical means is a promising approach towards novel spintronics devices. We report on the electric control of surface magnetism in Cr2O3 thin films and uniaxial anisotropy in ferroelectric/ferromagnetic heterostructures, respectively. Artificial magnetoelectricity is realized in a BaTiO3/Fe heterostructure. Here, thermally induced coercivity changes of the Fe hysteresis loop are used to derive the stress imposed by the ferroelectric BaTiO3 substrate on the adjacent Fe film. Electrically induced coercivity changes give rise to a giant magnetoelectric susceptibility in the vicinity of the magnetic coercive field.

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Exact Lambda-Numbers Of Generalized Petersen Graphs Of Certain Higher-Orders And On Mobius Strips, Sarah Spence Adams, Paul Booth, Harold Jaffe, Denise Troxell, Luke Zinnen Feb 2012

Exact Lambda-Numbers Of Generalized Petersen Graphs Of Certain Higher-Orders And On Mobius Strips, Sarah Spence Adams, Paul Booth, Harold Jaffe, Denise Troxell, Luke Zinnen

Sarah Spence Adams

An L(2,1)-labeling of a graph G is an assignment f of nonnegative integers to the vertices of G such that if vertices x and y are adjacent, |f(x)−f(y)|≥2, and if x and y are at distance two, |f(x)−f(y)|≥1. The λ-number of Gis the minimum span over all L(2,1)-labelings of G. A generalized Petersen graph (GPG) of order n consists of two disjoint copies of cycles on n vertices together with a perfect matching between the two vertex sets. By …

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Multi-Channel Peer-To-Peer Streaming Systems As Resource Allocation Problems, Miao Wang Feb 2012

Multi-Channel Peer-To-Peer Streaming Systems As Resource Allocation Problems, Miao Wang

Miao Wang

In the past few years, the Internet has witnessed the success of Peer-to-Peer (P2P) streaming technology, which has attracted millions of users. More recently, commercial P2P streaming systems have begun to support multiple channels and a user in such systems is allowed to watch more than one channel at a time. We refer to such systems as multi-channel P2P streaming systems. In this dissertation, we focus on designing multi-channel P2P streaming systems with the goal of providing optimal streaming quality for all channels, termed as system-wide optimal streaming quality. Specifically, we design the systems from the perspective of how to …

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