The document summarizes the research activity of Antonio F. Di Rienzo over the past three years. It discusses using the lattice Boltzmann method to solve the radiative transfer equation, developing a lattice Boltzmann model for reactive flows that can account for large temperature variations, and a new link-wise artificial compressibility method beyond lattice Boltzmann.
This document discusses superdiffusion of waves in random media. It describes how Lévy walks, which involve random walks with heavy-tailed step lengths, can lead to superdiffusion described by fractional diffusion equations. This results in anomalous transport properties like superdiffusive propagation. The document also discusses how interference effects between multiply scattered waves can occur and be observed through phenomena like coherent backscattering in such disordered media exhibiting superdiffusion.
Dresden 2014 A tour of some fractional models and the physics behind themNick Watkins
This document provides a summary of fractional models and the physics they seek to describe. It begins with an overview of classical Brownian motion and diffusion models, highlighting the central limit theorem, Wiener process, Langevin equation, and fluctuation-dissipation theorem. It then discusses two approaches to generalizing these models: fractional kinetics via continuous time random walks, which modifies diffusion through time subordination; and fractional motions like fractional Brownian motion, which derive from non-Markovian generalizations of the Langevin equation. The document aims to build intuition about these fractional models and their relationships to underlying physical phenomena.
Link-wise Artificial Compressibility Method: a simple way to deal with comple...FabioDiRienzo
The document summarizes the Link-wise Artificial Compressibility Method (LW-ACM), which is a simplified version of the Lattice Boltzmann Method (LBM) for solving fluid flow problems with complex geometries on structured grids. It discusses how LW-ACM modifies the standard Artificial Compressibility Method (ACM) to use a link-wise formulation that borrows ideas from LBM to handle boundaries without needing complex mesh generation. The document provides examples showing LW-ACM can accurately simulate flows like Couette flow and Couette flow with wall injection on simple structured grids.
This document summarizes research on modeling wildfires and turbulent premixed combustion. It discusses how turbulence affects wildfire propagation through turbulent transport of hot air, making the fire front position random. It presents a level set method for modeling deterministic and random fire fronts, accounting for turbulence. It also discusses using a Lagrangian approach to model turbulent premixed combustion, describing how the burned mass fraction evolves due to particle motion, flame front velocity, and curvature.
Black hole microstate geometries from string amplitudesdjt36
The non-trivial features of supergravity fields corresponding to D-brane bound states can be calculated from string amplitudes. This allows certain supergravity solutions to be identified as gravitational descriptions of particular microscopic bound states. This identification can provide insights into possible descriptions of BPS black holes in supergravity. String amplitudes are used to reproduce the asymptotic behavior of supergravity fields for D1-D5 bound states. The solutions differ from the naive D1-D5 geometry at order 1/r3 and these terms can be calculated from disk amplitudes with mixed boundary conditions.
The document summarizes research on discriminating kinetic models for the isomerization of n-butene to isobutene. Two proposed mechanisms from literature were analyzed using a general rate equation method. Experimental data was used to test the mechanisms. Mechanism (b), where the byproduct polyisobutene is produced from the addition of isobutene to an intermediate, was identified as the reasonable mechanism for the reaction based on its ability to accurately predict yield ratios from the experimental data. The general rate equation method allowed analysis of the mechanisms without assuming any rate-determining steps.
Nonlinear transport phenomena: models, method of solving and unusual features...SSA KPI
The document is a lecture on nonlinear transport phenomena and patterns. It discusses heat transport models described by balance equations. The key equations presented are the heat transport balance equation and the resulting partial differential equation in one spatial variable. The lecture aims to discuss patterns supported by various transport equations, defined as non-monotonic solutions that maintain shape or evolve self-similarly over time.
This document discusses superdiffusion of waves in random media. It describes how Lévy walks, which involve random walks with heavy-tailed step lengths, can lead to superdiffusion described by fractional diffusion equations. This results in anomalous transport properties like superdiffusive propagation. The document also discusses how interference effects between multiply scattered waves can occur and be observed through phenomena like coherent backscattering in such disordered media exhibiting superdiffusion.
Dresden 2014 A tour of some fractional models and the physics behind themNick Watkins
This document provides a summary of fractional models and the physics they seek to describe. It begins with an overview of classical Brownian motion and diffusion models, highlighting the central limit theorem, Wiener process, Langevin equation, and fluctuation-dissipation theorem. It then discusses two approaches to generalizing these models: fractional kinetics via continuous time random walks, which modifies diffusion through time subordination; and fractional motions like fractional Brownian motion, which derive from non-Markovian generalizations of the Langevin equation. The document aims to build intuition about these fractional models and their relationships to underlying physical phenomena.
Link-wise Artificial Compressibility Method: a simple way to deal with comple...FabioDiRienzo
The document summarizes the Link-wise Artificial Compressibility Method (LW-ACM), which is a simplified version of the Lattice Boltzmann Method (LBM) for solving fluid flow problems with complex geometries on structured grids. It discusses how LW-ACM modifies the standard Artificial Compressibility Method (ACM) to use a link-wise formulation that borrows ideas from LBM to handle boundaries without needing complex mesh generation. The document provides examples showing LW-ACM can accurately simulate flows like Couette flow and Couette flow with wall injection on simple structured grids.
This document summarizes research on modeling wildfires and turbulent premixed combustion. It discusses how turbulence affects wildfire propagation through turbulent transport of hot air, making the fire front position random. It presents a level set method for modeling deterministic and random fire fronts, accounting for turbulence. It also discusses using a Lagrangian approach to model turbulent premixed combustion, describing how the burned mass fraction evolves due to particle motion, flame front velocity, and curvature.
Black hole microstate geometries from string amplitudesdjt36
The non-trivial features of supergravity fields corresponding to D-brane bound states can be calculated from string amplitudes. This allows certain supergravity solutions to be identified as gravitational descriptions of particular microscopic bound states. This identification can provide insights into possible descriptions of BPS black holes in supergravity. String amplitudes are used to reproduce the asymptotic behavior of supergravity fields for D1-D5 bound states. The solutions differ from the naive D1-D5 geometry at order 1/r3 and these terms can be calculated from disk amplitudes with mixed boundary conditions.
The document summarizes research on discriminating kinetic models for the isomerization of n-butene to isobutene. Two proposed mechanisms from literature were analyzed using a general rate equation method. Experimental data was used to test the mechanisms. Mechanism (b), where the byproduct polyisobutene is produced from the addition of isobutene to an intermediate, was identified as the reasonable mechanism for the reaction based on its ability to accurately predict yield ratios from the experimental data. The general rate equation method allowed analysis of the mechanisms without assuming any rate-determining steps.
Nonlinear transport phenomena: models, method of solving and unusual features...SSA KPI
The document is a lecture on nonlinear transport phenomena and patterns. It discusses heat transport models described by balance equations. The key equations presented are the heat transport balance equation and the resulting partial differential equation in one spatial variable. The lecture aims to discuss patterns supported by various transport equations, defined as non-monotonic solutions that maintain shape or evolve self-similarly over time.
This document contains lecture notes on exponential growth and decay from a Calculus I class at New York University. It begins with announcements about an upcoming review session, office hours, and midterm exam. It then outlines the topics to be covered, including the differential equation y=ky, modeling population growth, radioactive decay including carbon-14 dating, Newton's law of cooling, and continuously compounded interest. Examples are provided of solving various differential equations representing exponential growth or decay. The document explains that many real-world situations exhibit exponential behavior due to proportional growth rates.
Dependence of Charge Carriers Mobility in the P-N-Heterojunctions on Composit...msejjournal
In this paper we consider manufacturing a p-n-junctions by dopant diffusion or ion implantation into a multilayer structure. We introduce an approach to increase sharpness of these p-n-junctions and at the same time to increase homogeneity of distributions of dopants in enriched by these dopants areas. We consider influence of the above changing of distribution of dopant on charge carrier mobility. We also consider an approach to decrease value of mismatch-induced stress in the considered multilayer structure by using a buffer layer. The decreasing gives a possibility to increase value of charge carrier mobility.
This document discusses applying renewal theorems to analyze the exponential moments of local times of Markov processes. It contains three main points:
1) If γ is greater than 1/G∞(i,i), the expected exponential moment grows exponentially over time.
2) If γ equals 1/G∞(i,i), the expected exponential moment grows linearly over time if H∞(i,i) is finite, and sublinearly otherwise.
3) If γ is less than 1/G∞(i,i), the expected exponential moment converges to a constant as time increases.
The analysis simplifies and strengthens previous results by framing the problem as a renewal
This document is a master's thesis written in Chinese that investigates the existence and uniqueness of solutions to stochastic differential equations (SDEs) with Lévy noise and non-Lipschitz coefficients. It introduces Lévy processes and their properties, including the Lévy-Itô decomposition. It defines stochastic integration with respect to compensated Poisson processes and provides Itô's formula for Lévy diffusions. The thesis proves that if weak existence and pathwise uniqueness hold for an SDE with Lévy noise, then it has a unique strong solution. It establishes conditions on the coefficients that ensure infinite lifetime and pathwise uniqueness of the solution.
This document contains notes from a Calculus I class at New York University. It discusses related rates problems, which involve taking derivatives of equations relating changing quantities to determine rates of change. The document provides examples of related rates problems involving an oil slick, two people walking towards and away from each other, and electrical resistors. It also outlines strategies for solving related rates problems, such as drawing diagrams, introducing notation, relating quantities with equations, and using the chain rule to solve for unknown rates.
This document discusses noncommutative quantum field theory, where the coordinates do not commute. It begins by motivating noncommutativity from theories of quantum gravity and string theory. It then introduces the Moyal product to write actions for noncommutative fields. While Lorentz symmetry is broken, the actions are still invariant under a twisted Poincaré algebra. Representations are classified by mass and spin as in ordinary theories. The document considers both space-like and time-like noncommutativity, but argues that time-like noncommutativity poses challenges for perturbative unitarity.
The document discusses a model of thermal sneutrino dark matter in the FD-term model of hybrid inflation. The FD-term model extends the MSSM with an inflaton-waterfall sector generating an effective μ-term and neutrino masses. During hybrid inflation, the inflaton field acquires a vacuum expectation value that breaks supersymmetry, giving masses to the right-handed sneutrino. Thermal production of right-handed sneutrinos in the early universe can account for the observed dark matter abundance if the sneutrinos annihilate via Yukawa interactions.
[L'angolo del PhD] Sara Borroni - XXIII Ciclo - 2010accatagliato
This thesis is focused on the study of the Z -> µ+ µ- process. This process is quite interesting. From the detector performance point of view, it can be used to measure from data muon trigger and reconstruction efficiencies. To extract these efficiencies, in the past three years I developed and optimized a method, called Tag&Probe, using Monte Carlo simulation. In the past few months, with the first ATLAS data, it allowed to measure the muon efficiencies from data for the first time. A data sample of 1.3 pb^-1 of integrated luminosity has been used and the results have been compared with the MC expectations.
The efficiencies estimation is also relevant for the cross-section measurement of all processes involving muons. In fact, when comparing the measured cross-section from data with the theoretical expectations, one has to correct for the detector inefficiencies, which at the start-ip are not perfectly reproduced in the simulation. In this thesis, these muon efficiencies have been used for a first data/MC comparison of the Z -> µ+ µ- cross-section, both inclusive and differential as a function of the jet multiplicity.
This document outlines Antonio Di Rienzo's PhD defense presentation on mesoscopic numerical methods for reactive flows. The presentation covers:
1. The Link-wise Artificial Compressibility Method (LW-ACM), which solves the incompressible Navier-Stokes equations using kinetic mock-up models in a similar way to the Lattice Boltzmann Method (LBM).
2. Using LBM to solve the Radiative Transfer Equation by updating intensity according to lattice velocities.
3. A new LBM model for simulating reactive flows that addresses current limitations in modeling combustion processes.
Dokumen ini membahas tentang tingkat kepuasan nasabah atas pelayanan karyawan Bank BRI Cabang Palembang Sriwijaya. Tujuan penelitian ini adalah untuk mengetahui tingkat kepuasan nasabah terhadap pelayanan karyawan BRI Unit tersebut. Hasil penelitian diharapkan dapat menjadi masukan untuk meningkatkan kualitas pelayanan dan menarik lebih banyak nasabah.
Web Copy Optimization http://www.advmedialab.com/ - Perché è così importante ottimizzare i contenuti del proprio website? Com'è possibile unire Web e SEO Copy? Nel workshop vengono delineati scenari, elementi, linee guida e best practices utili alla creazione di contenuti efficaci per website di prodotto ed eCommerce.
Sanyam Rastogi is currently working as a Software Engineer at Tavant Technologies in Bangalore since June 2013. He has experience with technologies like C#, .NET, HTML, Microsoft SQL Server, Oracle, and IDEs such as Visual Studio. He has strong skills in areas like data structures, databases, and object-oriented programming. His past projects include work on point of sale systems, inventory management, and remote desktop applications.
A resume for Brandon Jacobs. Brandon is a student at Marian University in Fond du Lac, Wisconsin. He is a major in graphic arts and a minor in studio arts.
Berdasarkan survei kepada 100 nasabah BRI Cabang Palembang Sriwijaya, pelayanan cabang tersebut dinilai memuaskan. Pelayanan keuangan dan non-keuangan seperti kecepatan layanan, keramahan petugas, dan fasilitas cabang dinilai baik secara umum oleh nasabah. Saran untuk cabang adalah mempertahankan kualitas pelayanan yang memuaskan, meningkatkan pelatihan petugas, serta program untuk mempertahankan loyalitas
Asia Tengah terdiri dari 5 negara bekas Uni Soviet yaitu Kazakhstan, Kyrgyzstan, Tajikistan, Turkmenistan, dan Uzbekistan dengan luas total sekitar 4.000.000 km2 dan populasi lebih dari 60 juta jiwa. Definisi Asia Tengah bervariasi namun umumnya mencakup wilayah tersebut.
Este documento presenta preguntas sobre un texto literario. En la primera sección, se pide responder 10 preguntas verdadero o falso. La segunda sección contiene 4 preguntas de selección múltiple sobre detalles del texto. La tercera sección pide respuestas completas a 6 preguntas sobre sucesos y personajes de la historia. El documento evalúa la comprensión lectora del estudiante sobre un cuento mapuche.
The document provides information about upcoming events at KELC in June, including field trips to the library to see birds and giraffes, preschool graduation, and a community picnic. It reminds parents to send towels for swimming and lists closed days in 2016. It also shares news from the classrooms about a past field trip to Dunham's Tavern and planting a tree as part of an arboretum opening, and notes that 17 children will graduate preschool.
Penyelesaian pertikaian secara berkesan bagi pertikaian berkaitan dengan skim...Sr Ezwan Bustamin
Ada beberapa kaedah alternatif untuk menyelesaikan pertikaian strata secara murah dan cepat tanpa melalui litigasi, termasuk rundingan, mediasi, dan konsiliasi. Kaedah-kaedah ini informal, sukarela, dan murah, tetapi tidak mempunyai ikatan undang-undang. Kaedah formal seperti tribunal strata memberikan keputusan yang mengikat secara undang-undang tetapi lebih mahal. Oleh itu, kaedah penyelesaian
This document contains lecture notes on exponential growth and decay from a Calculus I class at New York University. It begins with announcements about an upcoming review session, office hours, and midterm exam. It then outlines the topics to be covered, including the differential equation y=ky, modeling population growth, radioactive decay including carbon-14 dating, Newton's law of cooling, and continuously compounded interest. Examples are provided of solving various differential equations representing exponential growth or decay. The document explains that many real-world situations exhibit exponential behavior due to proportional growth rates.
Dependence of Charge Carriers Mobility in the P-N-Heterojunctions on Composit...msejjournal
In this paper we consider manufacturing a p-n-junctions by dopant diffusion or ion implantation into a multilayer structure. We introduce an approach to increase sharpness of these p-n-junctions and at the same time to increase homogeneity of distributions of dopants in enriched by these dopants areas. We consider influence of the above changing of distribution of dopant on charge carrier mobility. We also consider an approach to decrease value of mismatch-induced stress in the considered multilayer structure by using a buffer layer. The decreasing gives a possibility to increase value of charge carrier mobility.
This document discusses applying renewal theorems to analyze the exponential moments of local times of Markov processes. It contains three main points:
1) If γ is greater than 1/G∞(i,i), the expected exponential moment grows exponentially over time.
2) If γ equals 1/G∞(i,i), the expected exponential moment grows linearly over time if H∞(i,i) is finite, and sublinearly otherwise.
3) If γ is less than 1/G∞(i,i), the expected exponential moment converges to a constant as time increases.
The analysis simplifies and strengthens previous results by framing the problem as a renewal
This document is a master's thesis written in Chinese that investigates the existence and uniqueness of solutions to stochastic differential equations (SDEs) with Lévy noise and non-Lipschitz coefficients. It introduces Lévy processes and their properties, including the Lévy-Itô decomposition. It defines stochastic integration with respect to compensated Poisson processes and provides Itô's formula for Lévy diffusions. The thesis proves that if weak existence and pathwise uniqueness hold for an SDE with Lévy noise, then it has a unique strong solution. It establishes conditions on the coefficients that ensure infinite lifetime and pathwise uniqueness of the solution.
This document contains notes from a Calculus I class at New York University. It discusses related rates problems, which involve taking derivatives of equations relating changing quantities to determine rates of change. The document provides examples of related rates problems involving an oil slick, two people walking towards and away from each other, and electrical resistors. It also outlines strategies for solving related rates problems, such as drawing diagrams, introducing notation, relating quantities with equations, and using the chain rule to solve for unknown rates.
This document discusses noncommutative quantum field theory, where the coordinates do not commute. It begins by motivating noncommutativity from theories of quantum gravity and string theory. It then introduces the Moyal product to write actions for noncommutative fields. While Lorentz symmetry is broken, the actions are still invariant under a twisted Poincaré algebra. Representations are classified by mass and spin as in ordinary theories. The document considers both space-like and time-like noncommutativity, but argues that time-like noncommutativity poses challenges for perturbative unitarity.
The document discusses a model of thermal sneutrino dark matter in the FD-term model of hybrid inflation. The FD-term model extends the MSSM with an inflaton-waterfall sector generating an effective μ-term and neutrino masses. During hybrid inflation, the inflaton field acquires a vacuum expectation value that breaks supersymmetry, giving masses to the right-handed sneutrino. Thermal production of right-handed sneutrinos in the early universe can account for the observed dark matter abundance if the sneutrinos annihilate via Yukawa interactions.
[L'angolo del PhD] Sara Borroni - XXIII Ciclo - 2010accatagliato
This thesis is focused on the study of the Z -> µ+ µ- process. This process is quite interesting. From the detector performance point of view, it can be used to measure from data muon trigger and reconstruction efficiencies. To extract these efficiencies, in the past three years I developed and optimized a method, called Tag&Probe, using Monte Carlo simulation. In the past few months, with the first ATLAS data, it allowed to measure the muon efficiencies from data for the first time. A data sample of 1.3 pb^-1 of integrated luminosity has been used and the results have been compared with the MC expectations.
The efficiencies estimation is also relevant for the cross-section measurement of all processes involving muons. In fact, when comparing the measured cross-section from data with the theoretical expectations, one has to correct for the detector inefficiencies, which at the start-ip are not perfectly reproduced in the simulation. In this thesis, these muon efficiencies have been used for a first data/MC comparison of the Z -> µ+ µ- cross-section, both inclusive and differential as a function of the jet multiplicity.
This document outlines Antonio Di Rienzo's PhD defense presentation on mesoscopic numerical methods for reactive flows. The presentation covers:
1. The Link-wise Artificial Compressibility Method (LW-ACM), which solves the incompressible Navier-Stokes equations using kinetic mock-up models in a similar way to the Lattice Boltzmann Method (LBM).
2. Using LBM to solve the Radiative Transfer Equation by updating intensity according to lattice velocities.
3. A new LBM model for simulating reactive flows that addresses current limitations in modeling combustion processes.
Dokumen ini membahas tentang tingkat kepuasan nasabah atas pelayanan karyawan Bank BRI Cabang Palembang Sriwijaya. Tujuan penelitian ini adalah untuk mengetahui tingkat kepuasan nasabah terhadap pelayanan karyawan BRI Unit tersebut. Hasil penelitian diharapkan dapat menjadi masukan untuk meningkatkan kualitas pelayanan dan menarik lebih banyak nasabah.
Web Copy Optimization http://www.advmedialab.com/ - Perché è così importante ottimizzare i contenuti del proprio website? Com'è possibile unire Web e SEO Copy? Nel workshop vengono delineati scenari, elementi, linee guida e best practices utili alla creazione di contenuti efficaci per website di prodotto ed eCommerce.
Sanyam Rastogi is currently working as a Software Engineer at Tavant Technologies in Bangalore since June 2013. He has experience with technologies like C#, .NET, HTML, Microsoft SQL Server, Oracle, and IDEs such as Visual Studio. He has strong skills in areas like data structures, databases, and object-oriented programming. His past projects include work on point of sale systems, inventory management, and remote desktop applications.
A resume for Brandon Jacobs. Brandon is a student at Marian University in Fond du Lac, Wisconsin. He is a major in graphic arts and a minor in studio arts.
Berdasarkan survei kepada 100 nasabah BRI Cabang Palembang Sriwijaya, pelayanan cabang tersebut dinilai memuaskan. Pelayanan keuangan dan non-keuangan seperti kecepatan layanan, keramahan petugas, dan fasilitas cabang dinilai baik secara umum oleh nasabah. Saran untuk cabang adalah mempertahankan kualitas pelayanan yang memuaskan, meningkatkan pelatihan petugas, serta program untuk mempertahankan loyalitas
Asia Tengah terdiri dari 5 negara bekas Uni Soviet yaitu Kazakhstan, Kyrgyzstan, Tajikistan, Turkmenistan, dan Uzbekistan dengan luas total sekitar 4.000.000 km2 dan populasi lebih dari 60 juta jiwa. Definisi Asia Tengah bervariasi namun umumnya mencakup wilayah tersebut.
Este documento presenta preguntas sobre un texto literario. En la primera sección, se pide responder 10 preguntas verdadero o falso. La segunda sección contiene 4 preguntas de selección múltiple sobre detalles del texto. La tercera sección pide respuestas completas a 6 preguntas sobre sucesos y personajes de la historia. El documento evalúa la comprensión lectora del estudiante sobre un cuento mapuche.
The document provides information about upcoming events at KELC in June, including field trips to the library to see birds and giraffes, preschool graduation, and a community picnic. It reminds parents to send towels for swimming and lists closed days in 2016. It also shares news from the classrooms about a past field trip to Dunham's Tavern and planting a tree as part of an arboretum opening, and notes that 17 children will graduate preschool.
Penyelesaian pertikaian secara berkesan bagi pertikaian berkaitan dengan skim...Sr Ezwan Bustamin
Ada beberapa kaedah alternatif untuk menyelesaikan pertikaian strata secara murah dan cepat tanpa melalui litigasi, termasuk rundingan, mediasi, dan konsiliasi. Kaedah-kaedah ini informal, sukarela, dan murah, tetapi tidak mempunyai ikatan undang-undang. Kaedah formal seperti tribunal strata memberikan keputusan yang mengikat secara undang-undang tetapi lebih mahal. Oleh itu, kaedah penyelesaian
Hacking Sales - Sales 2.0 e Inbound SalesAdv Media Lab
Hacking sales significa trasformare il processo di vendita grazie agli strumenti digitali di nuova generazione, tattiche e nuove strategie. Partendo dall’edizione “Hacking Sales: The Playbook for Building a High-Velocity Sales Machine” di Max Altschuler, l’obiettivo è far evolvere totalmente la figura del venditore integrandolo al moderno (inbound) marketer.
The document summarizes Antonio Di Rienzo's PhD defense presentation on mesoscopic numerical methods for reactive flows. The presentation covered:
1. The Link-wise Artificial Compressibility Method (LW-ACM), a modification of the Artificial Compressibility Method that retains the link-wise formulation of the Lattice Boltzmann Method (LBM).
2. Using LBM to solve the Radiative Transfer Equation by updating intensity according to lattice velocities.
3. A consistent LBM model for simulating reactive flows that addresses lack of accurate combustion models in the LBM literature.
Ic technology- diffusion and ion implantationkriticka sharma
The document discusses various methods of doping semiconductors, including diffusion and ion implantation. It provides details on Fick's laws of diffusion and their solutions, which describe how dopant concentration changes over time during diffusion. The effects of temperature, electric fields, and oxidation on diffusion are also covered. Ion implantation is introduced as an alternative doping technique that allows for precise control of dopant dose and depth but requires annealing. Key advantages and challenges of each method are highlighted.
1) The document discusses using quantum probes to indirectly extract information about complex quantum systems like ultracold atomic gases, without directly measuring the system.
2) One method is to use an impurity atom as a qubit probe immersed in a 2D Bose-Einstein condensate. Interactions between the probe and gas induce decoherence on the probe that depends on properties of the gas like dimensionality and phase fluctuations, allowing characterization of the gas.
3) The non-Markovianity of the probe's dynamics, quantified by information flow between the probe and gas, can reveal information about the gas without directly measuring it. Positive information flow indicates non-Markovian dynamics and backflow of information
Presentation for the defense of my PhD Thesis in Mathematical Physics (Quantum Information Science) at the University of Trieste (Italy), on March 26th, 2010.
In this second lecture, I will discuss how to calculate polarization in terms of Berry phase, how to include GW correction in the real-time dynamics and electron-hole interaction.
An approach to decrease dimentions of logicalijcsa
In this paper we consider manufacturing logical elements with function AND-NOT based on bipolar transistors.Based on recently considered approach to decrease dimensions of solid state electronic devices with the same time increasing of their performance we introduce an approach to decrease dimensions of transistors and p-n-junctions, which became a part of the logical element. Framework the approach a heterostructure
with required configuration should be manufactured. After the manufacture required areas of the heterostructures should be doped by diffusion or ion implantation. The doping should be finished by optimized annealing of dopant and/or radiation defects.
This document provides an overview of chaos theory, including:
1) It defines chaos as the apparently noisy, aperiodic behavior in deterministic systems that is sensitive to initial conditions.
2) Important milestones in chaos theory research are discussed, from Poincare in 1890 to fractal geometry work in the 1970s.
3) Attractors, strange attractors, and fractal geometry are introduced as important concepts.
4) Methods for measuring chaos like Lyapunov exponents and entropy are described.
This document discusses the density-density correlation function of strongly inhomogeneous Luttinger liquids (LLs) with both forward scattering interactions between fermions and localized scalar impurities. It shows that the most singular contributions to the slow part of the asymptotic density-density correlation function can be expressed analytically in terms of simple functions involving only the bare transmission and reflection coefficients of single particles scattering from the impurities. This result is obtained using conventional fermionic perturbation theory resummed to all orders, along with the idea that higher-order connected moments of the density operator beyond the second order are less singular than the second order moment. This analytical form serves as an important input to the "Non-Chiral Bosonization Technique
The document discusses the importance of mathematics in describing ionic solutions, which play a key role in biology. It notes that while chemists have reliable quantitative data on ionic solutions, most theories ignore interactions between ions. This represents an opportunity for new mathematical approaches that can account for these interactions. The document advocates for developing a consistent theoretical framework, like the Energetic Variational Approach, to model ionic solutions in a way that replaces trial and error with computations. This would help provide insights into important biological and chemical processes that occur in ionic solutions.
An alternative to the "big molecules" view of proteins is the "small things" view in which protein have a shape and material properties. This talk is about investigating these properties.
On Decreasing of Dimensions of Field-Effect Transistors with Several Sourcesmsejjournal
We analyzed mass and heat transport during manufacturing field-effect heterotransistors with several
sources to decrease their dimensions. Framework the result of manufacturing it is necessary to manufacture
heterostructure with specific configuration. After that it is necessary to dope required areas of the heterostructure by diffusion or ion implantation to manufacture the required type of conductivity (p or n). After
the doping it is necessary to do optimize annealing. We introduce an analytical approach to prognosis mass
and heat transport during technological processes. Using the approach leads to take into account nonlinearity of mass and heat transport and variation in space and time (at one time) physical parameters of these
processes
ON DECREASING OF DIMENSIONS OF FIELDEFFECT TRANSISTORS WITH SEVERAL SOURCESmsejjournal
We analyzed mass and heat transport during manufacturing field-effect heterotransistors with several
sources to decrease their dimensions. Framework the result of manufacturing it is necessary to manufacture
heterostructure with specific configuration. After that it is necessary to dope required areas of the heterostructure by diffusion or ion implantation to manufacture the required type of conductivity (p or n). After
the doping it is necessary to do optimize annealing. We introduce an analytical approach to prognosis mass
and heat transport during technological processes. Using the approach leads to take into account nonlinearity of mass and heat transport and variation in space and time (at one time) physical parameters of these
processes
ON DECREASING OF DIMENSIONS OF FIELDEFFECT TRANSISTORS WITH SEVERAL SOURCESmsejjournal
This document analyzes mass and heat transport during manufacturing field-effect heterotransistors with several sources to decrease their dimensions. An analytical approach is introduced to model mass and heat transport during technological processes like doping and annealing. This approach accounts for nonlinearities in mass and heat transport and variations in physical parameters over space and time. The goal is to optimize doping distributions to increase compactness and homogeneity of transistor elements. Equations are developed to model concentration distributions of dopants and point defects over space and time during diffusion and ion implantation doping processes and subsequent annealing.
This document discusses problems with using tachyon condensation to drive inflation in string theory. It finds that inflation from tachyon condensation typically requires super-Planckian densities where the effective field theory breaks down. Additionally, if the tachyon potential minimum is at infinity, the tachyon field does not oscillate after inflation, making reheating and matter creation difficult. The tachyon would also always dominate the post-inflationary universe's energy density if it drove inflation. Successful inflation may require a second stage of inflation after the initial tachyon-driven stage.
Introduction to the phenomenology of HiTc superconductors.ABDERRAHMANE REGGAD
1. The document provides an introduction to the phenomenology of high-temperature superconductors (HiTc).
2. It discusses the basic physics of doped Mott insulators and experimental methods used to study HiTc superconductors such as thermodynamic measurements, transport properties, neutron scattering, and ARPES.
3. It also covers topics such as the pseudo-gap phase, the one-hole problem, properties at small doping levels, and properties of the superconducting state.
This study examines transport phenomena in an inhomogeneous quantum spin chain composed of two different semi-infinite spin chains connected at a junction. The study finds that relaxation dynamics within the light cone propagating from the junction occurs at different rates in different regions. Close to the light cone boundaries, a stationary current is rapidly approached, while near the junction the current continues decreasing slowly without reaching a steady state. This indicates two qualitatively different behaviors coexist - intermediate ballistic regions with fast relaxation and slow relaxation regions near the junction.
1. Mesoscopic numerical methods for
reactive flows: lattice Boltzmann
method and beyond
PhD Student: Antonio F. Di Rienzo
Advisors: P. Asinari, E. Chiavazzo
Energy Department (DENERG), Politecnico di Torino, Torino, Italy
PhD Day, Torino 20 December, 2011
Antonio F. Di Rienzo (Politecnico di Torino) PhD Day Torino, 20th December 2011 1 / 26
2. Outline of The Talk
1 Research activity: a flip through
2 The Lattice Boltzmann Method (LBM)
3 Radiative Transfer Equation
4 Reactive Flows
5 Link-wise Artificial Compressibility Method (LW-ACM)
Antonio F. Di Rienzo (Politecnico di Torino) PhD Day Torino, 20th December 2011 2 / 26
3. Research activity: a flip through
Outline Compass
1 Research activity: a flip through
2 The Lattice Boltzmann Method (LBM)
3 Radiative Transfer Equation
4 Reactive Flows
5 Link-wise Artificial Compressibility Method (LW-ACM)
Antonio F. Di Rienzo (Politecnico di Torino) PhD Day Torino, 20th December 2011 3 / 26
4. Research activity: a flip through
Over the past three years...
2009 1
The Radiative transfer equation (RTE) is solved by means of
lattice Boltzmann method (LBM) formalism: intensity is updated
according to lattice velocities.
2010-2011 2
A consistent lattice Boltzmann model for reactive flows has been
proposed, so as to overcome lacks of previous existing models (in
collaboration with the Paul Scherrer Institute, Switzerland).
2011 3
Link-wise Artificial Compressibility Method: CFD by kinetic
mock-up (beyond Lattice Boltzmann Method).
1
Di Rienzo A. F., Asinari P., Borchiellini R., Mishra S. C., Improved angular discretization and error analysis of
the lattice Boltzmann method for solving radiative heat transfer in a participating medium, IJNMH&FF, 21 (5),
640-662, 2011
2
Di Rienzo A. F., Asinari P., Chiavazzo E., Prasianakis N., Mantzaras J., A Lattice Boltzmann model for reactive
flows simulation, submitted
3
Asinari P., Ohwada T., Chiavazzo E., Di Rienzo A.F., Link-wise Artificial Compressiniblity Method, submitted
Antonio F. Di Rienzo (Politecnico di Torino) PhD Day Torino, 20th December 2011 4 / 26
5. The Lattice Boltzmann Method (LBM)
Outline Compass
1 Research activity: a flip through
2 The Lattice Boltzmann Method (LBM)
3 Radiative Transfer Equation
4 Reactive Flows
5 Link-wise Artificial Compressibility Method (LW-ACM)
Antonio F. Di Rienzo (Politecnico di Torino) PhD Day Torino, 20th December 2011 5 / 26
6. The Lattice Boltzmann Method (LBM)
What is Lattice Boltzmann Method?
"The lattice Boltzmann method (LBM) is used for the numerical
simulation of physical phenomena and serves as an alternative to
classical solvers of partial differential equation (PDEs)"
[www.lbmethod.org]. The main unknown is the discrete
distribution function, from which all relevant macroscopic
quantities can be derived.
The operative formula consists of the (a) relaxation process and
the (b) advection process:
(e)
fi (t + δt, x + ci δt) − fi (t, x) = ω fi (t, x) − fi (t, x) . (1)
The updating of fi is link-wise, in the sense that only the
informations along the directions identified by the lattice velocity ci
are required.
Antonio F. Di Rienzo (Politecnico di Torino) PhD Day Torino, 20th December 2011 6 / 26
7. Radiative Transfer Equation
Outline Compass
1 Research activity: a flip through
2 The Lattice Boltzmann Method (LBM)
3 Radiative Transfer Equation
4 Reactive Flows
5 Link-wise Artificial Compressibility Method (LW-ACM)
Antonio F. Di Rienzo (Politecnico di Torino) PhD Day Torino, 20th December 2011 7 / 26
8. Radiative Transfer Equation
Radiative Lattice Boltzmann Model
For an absorbing, emitting and scattering participating medium
and under the assumptions of isotropic scattering and radiative
equilibrium condition, radiative LBM reads:
G
Ii (t + δt, x + ci δt) = Ii (t, x) + ci β (t, x) − Ii (t, x) . (2)
4π
The link-wise formulation makes unnecessary to march from each
single corner (e.g. Finite Volumes).
The data structures for radiation are the same of those for the fluid
flow.
Antonio F. Di Rienzo (Politecnico di Torino) PhD Day Torino, 20th December 2011 8 / 26
10. Reactive Flows
Outline Compass
1 Research activity: a flip through
2 The Lattice Boltzmann Method (LBM)
3 Radiative Transfer Equation
4 Reactive Flows
5 Link-wise Artificial Compressibility Method (LW-ACM)
Antonio F. Di Rienzo (Politecnico di Torino) PhD Day Torino, 20th December 2011 10 / 26
11. Reactive Flows
State of Art for Reactive LBM
1 Filippova O., Hänel D., J. Comp. Phys., 2000
An additional factor is introduced in the kinetic equation in order to
model temporal changes of the density: constant density limitation
is removed.
The model behaves like a weak-compressible solver: not suitable to
accurately simulate thermal flows with large density and
temperature variations.
Energy and species transport equations are solved by means of a
finite differences scheme.
2 Yamamoto K., He X., Doolen G. D., J. Stat. Phys., 2002
Fully LBM based.
The flow field is incompressible and not affected by chemical
reactions: density is (nearly) constant.
Significant deviations are observed when compressibility is taken
into account.
Antonio F. Di Rienzo (Politecnico di Torino) PhD Day Torino, 20th December 2011 11 / 26
12. Reactive Flows
Simulating Reactive Flows: What’s Required?
"In principle, once lattice Boltzmann models can properly account
for large temperature variation, extension to reactive flows
essentially involves adding appropriate source terms..."[C. E.
Frouzakis, Fluid Mechanics and Its Applications, 2011]
So far, no reactive LBM models has been proposed that satisfies
this requirement.
Combustion problems exhibit significant temperature changes due
to the heat release in chemical reactions.
The LBM model is requested to accurately recover the Navier-
Stokes-Fourier equations, coupled to a transport equation for each
chemical species, and thus to behave macroscopically like a
compressible solver.
Antonio F. Di Rienzo (Politecnico di Torino) PhD Day Torino, 20th December 2011 12 / 26
13. Reactive Flows
Governing Equations for Reactive Flows
The system of macroscopic governing equations reads:
∂t ρ + · (ρu) = 0,
∂t (ρu) + · (ρu ⊗ u + pI) = · Π,
(3)
dp
∂t (ρhs ) + · (ρuhs + q) = +Π: u + ST ,
dt
∂t (ρYk ) + · (ρuYk ) = · (ρDk Yk ) + SYk . (4)
The corresponding kinetic equations reads:
2δt (e) 2δtτ
ft+δt = ft + ξt − ft + [Ψt + Φt + ST ], (5)
δt + 2τ δt + 2τ
(e)
gt+δt = gt + ωk gt − gt + SYk (6)
Antonio F. Di Rienzo (Politecnico di Torino) PhD Day Torino, 20th December 2011 13 / 26
14. Reactive Flows
Navier-Stokes-Fourier in the Compressible Limit
2δt (e) 2δtτ
ft+δt = ft + ξt − ft + [Ψt + Φt + ST ] (7)
δt + 2τ δt + 2τ
The correction terms Ψ and Φ are added to the discrete kinetic
equation in order to remove the deviations in the momentum and
energy equations.
By means of these correction terms, it is possible to accurately
recover Navier-Stokes-Fourier equations in the compressible
limit.4,5
This partially bridges over the lacks of the existing models: also
species transport equation must reckon with compressibility
effects.
4
Prasianakis N. I., Karlin I. V., Lattice Boltmann method for simulation of thermal flows on standard lattice, PRE,
2007, 76, 016702
5
Prasianakis N. I., Karlin I. V., Lattice Boltzmann method for simulation of compressible flows on standard
lattices, PRE, 2008, 78, 016704
Antonio F. Di Rienzo (Politecnico di Torino) PhD Day Torino, 20th December 2011 14 / 26
15. Reactive Flows
Species Equation in the Compressible Limit
Standard LBM solves the species transport equation with the
following deviation term:
· (Dk Yk ρ). (8)
Deviation in the species equation is activated in case of significant
compressibility effects (i.e. large ρ).
It can be removed without adding any correction terms, due to the
simpler nature of the equation.
By modifying the equilibrium distribution function, it is possible to
correct the second order moment, so that
(e) 1
c2 gi
i = Π(e) = ρmin Yk , (9)
3
and
∂t (ρYk ) + · (ρuYk ) = · ρmin Dk Yk + SYk . (10)
Antonio F. Di Rienzo (Politecnico di Torino) PhD Day Torino, 20th December 2011 15 / 26
16. Reactive Flows
Species Equation in the Compressible Limit
By relating the relaxation frequency to the density-weighted mass
diffusivity as:
1 1 1 2
ρDk = ρmin − c δt, (11)
3 ωk 2
the species equation in the compressible limit is recovered.
Through the suggested procedure, the most general advection-
diffusion-reaction transport equation can be solved. The particular
cases of weak-compressible and incompressible flows are readily
provided.
Since compressibility effects are accounted for both in Navier-
Stokes-Fourier and species equations, the proposed model is
actually suitable for simulating reactive flows.
Antonio F. Di Rienzo (Politecnico di Torino) PhD Day Torino, 20th December 2011 16 / 26
17. Reactive Flows
Reactive LBM at Work
We consider combustion of premixed stoichiometric H2 /Air
reactive mixture in a narrow channel.
Reactive LBM is validated against FLUENT for H2 +1/2O→H2 O.
Figure: Lines and symbols represent the LBM and FLUENT solutions, respectively
Antonio F. Di Rienzo (Politecnico di Torino) PhD Day Torino, 20th December 2011 17 / 26
18. Link-wise Artificial Compressibility Method (LW-ACM)
Outline Compass
1 Research activity: a flip through
2 The Lattice Boltzmann Method (LBM)
3 Radiative Transfer Equation
4 Reactive Flows
5 Link-wise Artificial Compressibility Method (LW-ACM)
Antonio F. Di Rienzo (Politecnico di Torino) PhD Day Torino, 20th December 2011 18 / 26
19. Link-wise Artificial Compressibility Method (LW-ACM)
Link-wise Artificial Compressibility Method
Let us consider the following formula 6 :
(e)
fi (x, t + δt) = fi (x − ci δt, t)
ω−1 (12)
(e,o) (e,o)
+2 fi (x, t) − fi (x − ci δt, t) ,
ω
The updating rule of Eq.(12) is link-wise in the sense that for
updating fi only the information along the direction identified by
the lattice velocity ci are required. This is similar to LBM.
The updating of fi is ruled only by hydrodynamic quantities, while
LBM works also with the so-called ghost variables, beyond the
hydrodynamic variables.
6
Asinari P., Ohwada T., Chiavazzo E., Di Rienzo A.F., Link-wise Artificial Compressibility Method, submitted
Antonio F. Di Rienzo (Politecnico di Torino) PhD Day Torino, 20th December 2011 19 / 26
20. Link-wise Artificial Compressibility Method (LW-ACM)
Simple Boundaries: Stealing from CFD
L2 [u] L2 [u]
δx M a ∝ δt/δx ν∝ Re−1 Test 1 Test 2
1 × 10−1 3 × 10−2 3 × 10−2 1.74 × 10−3 4.59 × 10−4
5 × 10−2 1.5 × 10−2 3 × 10−2 4.49 × 10−4 1.21 × 10−4
2.5 × 10−2 7.5 × 10−2 3 × 10−2 1.20 × 10−4 3.11 × 10−5
Antonio F. Di Rienzo (Politecnico di Torino) PhD Day Torino, 20th December 2011 20 / 26
21. Link-wise Artificial Compressibility Method (LW-ACM)
Complex Boundaries: Stealing from LBM
δx M a ∝ δt/δx ν ∝ Re−1 L2 [u]
5 × 10−2 3 × 10−1 4 × 10−2 1.84 × 10−3
1.5 × 10−2 1.5 × 10−1 4 × 10−2 3.83 × 10−4
1.25 × 10−2 7.5 × 10−1 4 × 10−2 1.11 × 10−4
Antonio F. Di Rienzo (Politecnico di Torino) PhD Day Torino, 20th December 2011 21 / 26
22. Link-wise Artificial Compressibility Method (LW-ACM)
2D Lid Driven Cavity Flow
Figure: Comparison between LW-ACM and BGK at Re = 5000: streamlines (top) and
pressure contours (bottom).
Antonio F. Di Rienzo (Politecnico di Torino) PhD Day Torino, 20th December 2011 22 / 26
23. Link-wise Artificial Compressibility Method (LW-ACM)
3D Diagonally Driven Cavity Flow
Figure: 3D diagonally driven cavity (a); flow at the middle plane MP at Re = 2000 (b);
velocity profile along the line ML (c) and the line RL (d) at Re = 700.
Antonio F. Di Rienzo (Politecnico di Torino) PhD Day Torino, 20th December 2011 23 / 26
24. Link-wise Artificial Compressibility Method (LW-ACM)
3D Diagonally Driven Cavity with Palabos
Palabos "[...] offers an access to the rich world of lattice
Boltzmann, even to an audience with restricted theoretical
knowledge of this method" [www.lbmethod.org].
Implementation of LW-ACM in Palabos is in progress (in
collaboration with the University of Geneva, Switzerland).
Figure: Flow in the plane perpendicular to the direction of the lid at Re = 700. Results
are obtained with the LW-ACM currently implemented in Palabos.
Antonio F. Di Rienzo (Politecnico di Torino) PhD Day Torino, 20th December 2011 24 / 26
25. Conclusions
1 A lattice Boltzmann scheme for simulating reactive flows has been
developed, so as to compensate for the limitations of previous
approaches. Accounting for compressibility effects in the
Navier-Stokes-Fourier and species equations, significant
temperature (density) variation can be handled.
2 Radiative LBM can be directly included (same data structures).
3 The LW-ACM has been proposed as an alternative to both
classical CFD and LBM, as long as incompressible and
weak-compressible flows are investigated. The link-wise
formulation preserves the ability of LBM in dealing with complex
geometries (no body-fitting is required), while the formulation in
terms of hydrodynamic quantities makes all existing CFD
technology readily available.
Antonio F. Di Rienzo (Politecnico di Torino) PhD Day Torino, 20th December 2011 25 / 26
26. Thank you for your attention!
Antonio F. Di Rienzo (Politecnico di Torino) PhD Day Torino, 20th December 2011 26 / 26