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Articles 1531 - 1560 of 3219

Full-Text Articles in Physical Sciences and Mathematics

Mechanisms Of Shear Zone Localization And Raman Thermobarometry In Spinel Peridotites From The Alpine Fault, New Zealand, Emily J. Lubicich Jan 2017

Mechanisms Of Shear Zone Localization And Raman Thermobarometry In Spinel Peridotites From The Alpine Fault, New Zealand, Emily J. Lubicich

Dissertations and Theses

A suite of xenoliths from two localities on South Island, New Zealand, exhibit rare microstructures and provide information on deformation during the early stages of development of the Alpine Fault. The first set of samples has evidence of dislocation creep with subgrains, recrystallized grains, undulose extinction and a lattice preferred orientation. These samples also show evidence of post deformation static grain growth with polygonal grains, 120° triple junctions, and euhedral grains within larger grains of the same phase. Samples from the second locality also show evidence of dislocation creep but with minimal static grain growth. This set also has a …


The Impact Of New York State's 2016 Mold Licensing Requirement On Indoor Air Quality Assessments, Angelo Lampousis, Mark Drozdov Jan 2017

The Impact Of New York State's 2016 Mold Licensing Requirement On Indoor Air Quality Assessments, Angelo Lampousis, Mark Drozdov

Publications and Research

As of January 2016, New York joined a select number of states in regulating mold. The New York State Department of Labor has approved mold-related training courses in three levels, ranging from two to four days. These include the mold abatement worker, mold remediation contractor, and mold assessor courses. In this presentation we share the experience obtained to date from delivering the above referenced courses and challenges as an approved training provider. We also evaluate the relative effectiveness of the mode of delivery as it relates to different audiences.


Recovery And Resilience Of Urban Stream Metabolism Following Superstorm Sandy And Other Floods, Alexander J. Reisinger, Emma J. Rosi, Heather A. Bechtold, Thomas R. Doody, Sujay S. Kaushal, Peter M. Groffman Jan 2017

Recovery And Resilience Of Urban Stream Metabolism Following Superstorm Sandy And Other Floods, Alexander J. Reisinger, Emma J. Rosi, Heather A. Bechtold, Thomas R. Doody, Sujay S. Kaushal, Peter M. Groffman

Publications and Research

Urban streams are exposed to multiple different stressors on a regular basis, with increased hydrological flashiness representing a common urban stream stressor. Stream metabolism, the coupled ecosystem functions of gross primary production (GPP) and ecosystem respiration (ER), controls numerous other ecosystem functions and integrates multiple processes occurring within streams. We examined the effect of one large (Superstorm Sandy) and multiple small and moderately sized flood events in Baltimore, Maryland, to quantify the response and recovery of urban stream GPP and ER before and after floods of different magnitudes. We also compared GPP and ER before and after Superstorm Sandy to …


What’S Brewing? A Statistics Education Discovery Project, Marla A. Sole, Sharon L. Weinberg Jan 2017

What’S Brewing? A Statistics Education Discovery Project, Marla A. Sole, Sharon L. Weinberg

Publications and Research

We believe that students learn best, are actively engaged, and are genuinely interested when working on real-world problems. This can be done by giving students the opportunity to work collaboratively on projects that investigate authentic, familiar problems. This article shares one such project that was used in an introductory statistics course. We describe the steps taken to investigate why customers are charged more for iced coffee than hot coffee, which included collecting data and using descriptive and inferential statistical analysis. Interspersed throughout the article, we describe strategies that can help teachers implement the project and scaffold material to assist students …


Technology Design: The Movement Of Means, Yu Gu Jan 2017

Technology Design: The Movement Of Means, Yu Gu

Open Educational Resources

In order to promote students’ conceptual understanding and learning experience in introductory statistics, a technology task, which focuses on the probability distribution in which means are defined, was created using TinkerPlots, an exploratory dataanalysis and modeling software. The targeted audiences range from senior high school grade levels to college freshmen who are starting their introductory course in statistics. Students will be guided to explore and discover the movement behaviors of means of a set of numbers randomly generated from a fixed range of values characterized by a predetermined probability distribution. The cognitive, mathematical, technological and pedagogical natures of the task, …


Supergroups In Critical Dimensions And Division Algebras, Čestmir Burdik, Sultan Catto, Yasemin Gürcan, Amish Khalfan, Levent Kurt, V. Kato La Jan 2017

Supergroups In Critical Dimensions And Division Algebras, Čestmir Burdik, Sultan Catto, Yasemin Gürcan, Amish Khalfan, Levent Kurt, V. Kato La

Publications and Research

We establish a link between classical heterotic strings and the groups of the magic square associated with Jordan algebras, allowing for a uniform treatment of the bosonic and superstring sectors of the heterotic string.


Disk Heating, Galactoseismology, And The Formation Of Stellar Halos, Kathryn V. Johnston, Adrian M. Price-Whelan, Maria Bergemann, Chervin F. P. Laporte, Ting S. Li, Allyson A. Sheffield, Steven R. Majewski, Rachael S. Beaton, Branimir Sesar, Sanjib Sharma Jan 2017

Disk Heating, Galactoseismology, And The Formation Of Stellar Halos, Kathryn V. Johnston, Adrian M. Price-Whelan, Maria Bergemann, Chervin F. P. Laporte, Ting S. Li, Allyson A. Sheffield, Steven R. Majewski, Rachael S. Beaton, Branimir Sesar, Sanjib Sharma

Publications and Research

Deep photometric surveys of the MilkyWay have revealed diffuse structures encircling our Galaxy far beyond the “classical” limits of the stellar disk. This paper reviews results from our own and other observational programs, which together suggest that, despite their extreme positions, the stars in these structures were formed in our Galactic disk. Mounting evidence from recent observations and simulations implies kinematic connections between several of these distinct structures. This suggests the existence of collective disk oscillations that can plausibly be traced all the way to asymmetries seen in the stellar velocity distribution around the Sun. There are multiple interesting implications …


Australian Shelf Sediments Reveal Shifts In Miocene Southern Hemisphere Westerlies, Jeroen Groeneveld, Jorijntje Henderiks, Willem Renema, Cecilia M. Mchugh, David De Vleeschouwer, Beth A. Christensen, Craig S. Fulthorpe, Lars Reuning, Stephen J. Gallagher, Kara Bogus, Gerald Auer, Takeshige Ishiwa, Expedition 356 Scientists Jan 2017

Australian Shelf Sediments Reveal Shifts In Miocene Southern Hemisphere Westerlies, Jeroen Groeneveld, Jorijntje Henderiks, Willem Renema, Cecilia M. Mchugh, David De Vleeschouwer, Beth A. Christensen, Craig S. Fulthorpe, Lars Reuning, Stephen J. Gallagher, Kara Bogus, Gerald Auer, Takeshige Ishiwa, Expedition 356 Scientists

Publications and Research

Global climate underwent a major reorganization when the Antarctic ice sheet expanded ~14 million years ago (Ma) (1). This event affected global atmospheric circulation, including the strength and position of the westerlies and the Intertropical Convergence Zone (ITCZ), and, therefore, precipitation patterns (2–5). We present new shallow-marine sediment records from the continental shelf of Australia (International Ocean Discovery Program Sites U1459 and U1464) providing the first empirical evidence linking high-latitude cooling around Antarctica to climate change in the (sub)tropics during the Miocene. We show that Western Australia was arid during most of the Middle Miocene. Southwest Australia became wetter during …


A Novel Approach For Library Materials Acquisition Using Discrete Particle Swarm Optimization, Daniel A. Sabol Jan 2017

A Novel Approach For Library Materials Acquisition Using Discrete Particle Swarm Optimization, Daniel A. Sabol

Publications and Research

The academic library materials acquisition problem is a challenge for librarian, since library cannot get enough funding from universities and the price of materials inflates greatly. In this paper, we analyze an integer mathematical model by considering the selection of acquired materials to maximize the average preference value as well as the budget execution rate under practical restrictions. The objective is to improve the Discrete Particle Swarm Optimization (DPSO) algorithm by adding a Simulate Annealing algorithm to reduce premature convergence. Furthermore, the algorithm is implemented in multiple threaded environment. The experimental results show the efficiency of this approach.


Circular Dichroistic Impacts Of 1‑(3-Dimethylaminopropyl)-3- Ethylurea: Secondary Structure Artifacts Arising From Bioconjugation Using 1‑Ethyl-3-[3-Dimethylaminopropyl]Carbodiimide, Matthew B. Kubilius, Raymond S. Tu Jan 2017

Circular Dichroistic Impacts Of 1‑(3-Dimethylaminopropyl)-3- Ethylurea: Secondary Structure Artifacts Arising From Bioconjugation Using 1‑Ethyl-3-[3-Dimethylaminopropyl]Carbodiimide, Matthew B. Kubilius, Raymond S. Tu

Publications and Research

1-Ethyl-3-[3-dimethylaminopropyl]carbodiimide (EDC) is a commonly used reagent for bioconjugation and peptide synthesis. Both EDC and the corresponding urea derivative, 1-(3-dimethylaminopropyl)-3-ethylurea (EDU), are achiral. As the reagent is active in aqueous solutions, it is a common choice for the study of evolving secondary structural changes via circular dichroism. This work highlights the effect of EDU on spectropolarimetric measurements, namely, the problematic absorption profile at low wavelengths (190−220 nm). We demonstrate that EDU is capable of erroneously indicating structural changes, particularly loss of α-helical character, through masking of the characteristic minimum at 208 nm. However, if the concentrations of the EDU in …


Comparing Cmaq Forecasts With A Neural Network Forecast Model For Pm2.5 In New York, Samuel D. Lightstone, Fred Moshary, Barry Gross Jan 2017

Comparing Cmaq Forecasts With A Neural Network Forecast Model For Pm2.5 In New York, Samuel D. Lightstone, Fred Moshary, Barry Gross

Publications and Research

Human health is strongly affected by the concentration of fine particulate matter (PM2.5). The need to forecast unhealthy conditions has driven the development of Chemical Transport Models such as Community Multi-Scale Air Quality (CMAQ). These models attempt to simulate the complex dynamics of chemical transport by combined meteorology, emission inventories (EI’s), and gas/particle chemistry and dynamics. Ultimately, the goal is to establish useful forecasts that could provide vulnerable members of the population with warnings. In the simplest utilization, any forecast should focus on next day pollution levels, and should be provided by the end of the business day (5 p.m. …


Gauge-Invariant Variables And Entanglement Entropy, V. Parameswaran Nair, Dimitra Karabali, Abhishek Agarawal Jan 2017

Gauge-Invariant Variables And Entanglement Entropy, V. Parameswaran Nair, Dimitra Karabali, Abhishek Agarawal

Publications and Research

The entanglement entropy (EE) of gauge theories in three spacetime dimensions is analyzed using manifestly gauge-invariant variables defined directly in the continuum. Specifically, we focus on the Maxwell, Maxwell-Chern-Simons (MCS), and nonabelian Yang-Mills theories. Special attention is paid to the analysis of edge modes and their contribution to EE. The contact term is derived without invoking the replica method and its physical origin is traced to the phase space volume measure for the edge modes. The topological contribution to the EE for the MCS case is calculated. For all the abelian cases, the EE presented in this paper agrees with …


Evaluation Of Extratropical Cyclone Precipitation In The North Atlantic Basin: An Analysis Of Era-Interim, Wrf, And Two Cmip5 Models, James F. Booth, Catherine M. Naud, Jeff Willison Jan 2017

Evaluation Of Extratropical Cyclone Precipitation In The North Atlantic Basin: An Analysis Of Era-Interim, Wrf, And Two Cmip5 Models, James F. Booth, Catherine M. Naud, Jeff Willison

Publications and Research

The representation of extratropical cyclones (ETCs) precipitation in general circulation models (GCMs) and a weather research and forecasting (WRF) model is analyzed. This work considers the link between ETC precipitation and dynamical strength and tests if parameterized convection affects this link for ETCs in the North Atlantic Basin. Lagrangian cyclone tracks of ETCs in ERA-Interim reanalysis (ERAI), the GISS and GFDL CMIP5 models, and WRF with two horizontal resolutions are utilized in a compositing analysis. The 20-km resolution WRF model generates stronger ETCs based on surface wind speed and cyclone precipitation. The GCMs and ERAI generate similar composite means and …


Arithmetic | Algebra Homework, Samar Elhitti, Ariane Masuda, Lin Zhou Jan 2017

Arithmetic | Algebra Homework, Samar Elhitti, Ariane Masuda, Lin Zhou

Open Educational Resources

Arithmetic | Algebra Homework book is a static version of the WeBWork online homework assignments that accompany the textbook Arithmetic | Algebra for the developmental math courses MAT 0630 and MAT 0650 at New York City College of Technology, CUNY.


Arithmetic | Algebra, Samar Elhitti, Marianna Bonanome, Holly Carley, Thomas Tradler, Lin Zhou Jan 2017

Arithmetic | Algebra, Samar Elhitti, Marianna Bonanome, Holly Carley, Thomas Tradler, Lin Zhou

Open Educational Resources

Arithmetic | Algebra provides a customized open-source textbook for the math developmental students at New York City College of Technology. The book consists of short chapters, addressing essential concepts necessary to successfully proceed to credit-level math courses. Each chapter provides several solved examples and one unsolved “Exit Problem”. Each chapter is also supplemented by its own WeBWork online homework assignment. The book can be used in conjunction with WeBWork for homework (online) or with the Arithmetic | Algebra Homework handbook (traditional). The content in the book, WeBWork and the homework handbook are also aligned to prepare students for the CUNY …


Automated Refactoring Of Legacy Java Software To Default Methods, Raffi T. Khatchadourian, Hidehiko Masuhara Jan 2017

Automated Refactoring Of Legacy Java Software To Default Methods, Raffi T. Khatchadourian, Hidehiko Masuhara

Publications and Research

Java 8 default methods, which allow interfaces to contain (instance) method implementations, are useful for the skeletal implementation software design pattern. However, it is not easy to transform existing software to exploit default methods as it requires analyzing complex type hierarchies, resolving multiple implementation inheritance issues, reconciling differences between class and interface methods, and analyzing tie-breakers (dispatch precedence) with overriding class methods to preserve type-correctness and confirm semantics preservation. In this paper, we present an efficient, fully-automated, type constraint-based refactoring approach that assists developers in taking advantage of enhanced interfaces for their legacy Java software. The approach features an extensive …


Detecting Broken Pointcuts Using Structural Commonality And Degree Of Interest, Raffi T. Khatchadourian, Awais Rashid, Hidehiko Masuhara, Takuya Watanabe Jan 2017

Detecting Broken Pointcuts Using Structural Commonality And Degree Of Interest, Raffi T. Khatchadourian, Awais Rashid, Hidehiko Masuhara, Takuya Watanabe

Publications and Research

Pointcut fragility is a well-documented problem in Aspect-Oriented Programming; changes to the base-code can lead to join points incorrectly falling in or out of the scope of pointcuts. Deciding which pointcuts have broken due to base-code changes is a daunting venture, especially in large and complex systems. We present an automated approach that recommends pointcuts that are likely to require modification due to a particular base-code change, as well as ones that do not. Our hypothesis is that join points selected by a pointcut exhibit common structural characteristics. Patterns describing such commonality are used to recommend pointcuts that have potentially …


Dynamical Systems Modeling To Identify A Cohort Of Problem Drinkers With Similar Mechanisms Of Behavior Change, Kidist Maxwell, Rebecca Everett, Sijing Shao, Alexis Kuerbis, Lyric Stephenson, H. T. Banks, Jon Morgenstern Jan 2017

Dynamical Systems Modeling To Identify A Cohort Of Problem Drinkers With Similar Mechanisms Of Behavior Change, Kidist Maxwell, Rebecca Everett, Sijing Shao, Alexis Kuerbis, Lyric Stephenson, H. T. Banks, Jon Morgenstern

Publications and Research

One challenge to understanding mechanisms of behavior change (MOBC) completely among individuals with alcohol use disorder is that processes of change are theorized to be complex, dynamic (time varying), and at times non-linear, and they interact with each other to influence alcohol consumption. We used dynamical systems modeling to better understand MOBC within a cohort of problem drinkers undergoing treatment. We fit a mathematical model to ecological momentary assessment data from individual patients who successfully reduced their drinking by the end of the treatment. The model solutions agreed with the trend of the data reasonably well, suggesting the cohort patients …


Existence Conditions Of Super-Replication Cost In A Multinomial Model, Mei Xing Jan 2017

Existence Conditions Of Super-Replication Cost In A Multinomial Model, Mei Xing

Publications and Research

This paper gives a theorem for the continuous time super-replication cost of European options in an unbounded multinomial market. An approximation multinomial scheme is put forward on a finite time interval [0,1] corresponding to a pure jump Levy model with unbounded jumps. Under the assumption that the expected underlying stock price at time 1 is bounded, the limit of the sequence of the super-replication cost in a multinomial model is proved to be greater than or equal to an optimal control problem. Furthermore, it is discussed that the existence conditions of a super-replication cost and a liquidity premium for the …


Enzymatically Active Microspheres For Self-Propelled Colloidal Engines, Jungeun Park Jan 2017

Enzymatically Active Microspheres For Self-Propelled Colloidal Engines, Jungeun Park

Dissertations and Theses

Micro- and nano-motors have attracted numerous attentions from various scientific areas due to their potential applications. Most studies on self-propelled colloidal engines have exploited catalytic decomposition of hydrogen peroxide to drive the motor. Since the hydrogen peroxide is caustic, it is not suitable to use in biological applications, encouraging people to develop “greener” fuels. The aim of this research is to study a new transduction mechanism for self-propulsion not tied to hydrogen peroxide, and which can in particular be used with biological molecules as fuels. In this study, we focus on making particles with enzymatic activity which can effectively decompose …


Temporal Variability Of Fluorescent Dissolved Organic Matter At A Brackish, Tidal Marsh-Estuary Interface, Alana B. Menendez Jan 2017

Temporal Variability Of Fluorescent Dissolved Organic Matter At A Brackish, Tidal Marsh-Estuary Interface, Alana B. Menendez

Dissertations and Theses

Marshes are both terrestrial and aqueous, sitting as an intermediate between land and water. Studies over constrained numbers of tidal cycles have demonstrated that these marshes are net exporters of dissolved organic carbon (DOC) to adjoining estuaries, however, there is need for continuous monitoring to better understand the temporal variability of this flux: tidally, seasonally, and during episodic rain events. Through use of a YSI EXO2 sonde, an in situ optical sensor at the interface of the brackish, tidal Kirkpatrick Marsh and Rhode River sub-estuary in Edgewater, Maryland (located on the northwestern shore of the Chesapeake Bay), we were able …


2d Vector Map And Database Design For Indoor Assisted Navigation, Luciano Caraciolo Albuquerque Jan 2017

2d Vector Map And Database Design For Indoor Assisted Navigation, Luciano Caraciolo Albuquerque

Dissertations and Theses

In this paper we implemented a 2D Vector Map, map editor and Database design intended to provide an efficient way to convert cad files from indoor environments to a set of vectors representing hallways, doors, exits, elevators, and other entities embedded in a floor plan, and save them in a database for use by other applications, such as assisted navigation for blind people.

A graphical application as developed in C++ to allow the user to input a CAD DXF file, process the file to automatically obtain nodes and edges, and save the nodes and edges to a database for posterior …


Marsh-Exported Dissolved Organic Matter Fate In Estuaries, Laura Ann Logozzo Jan 2017

Marsh-Exported Dissolved Organic Matter Fate In Estuaries, Laura Ann Logozzo

Dissertations and Theses

Dissolved organic matter (DOM) is a significant driver of estuarine productivity and nutrient cycling. The colored component of DOM, chromophoric dissolved organic matter (CDOM), impacts coastal optical properties, ocean color, and light attenuation. While marshes are largely considered sinks for carbon due to their high productivity and low soil carbon degradation rates, laterally they are sources of carbon as optically and chemically distinct DOM to surrounding aquatic ecosystems; these inputs are often essential in sustaining a net heterotrophic system. However, the photoreactivity and bioavailability of marsh-exported DOM is largely uncategorized, thus making it difficult to quantify its impacts on estuarine …


Teaching Size And Power Properties Of Hypothesis Tests Through Simulations, Suleyman Taspinar, Osman Dogan Jan 2017

Teaching Size And Power Properties Of Hypothesis Tests Through Simulations, Suleyman Taspinar, Osman Dogan

Publications and Research

In this study, we review the graphical methods suggested in Davidson and MacKinnon (Davidson, Russell, and James G. MacKinnon. 1998. “Graphical Methods for Investigating the Size and Power of Hypothesis Tests.” The Manchester School 66 (1): 1–26.) that can be used to investigate size and power properties of hypothesis tests for undergraduate and graduate econometrics courses. These methods can be used to assess finite sample properties of various hypothesis tests through simulation studies. In addition, these methods can be effectively used in classrooms to reinforce students’ understanding of basic hypothesis testing concepts such as Type I error, Type II error, …


Schrödinger Theory Of Electrons In Electromagnetic Fields: New Perspectives, Viraht Sahni, Xiao-Yin Pan Jan 2017

Schrödinger Theory Of Electrons In Electromagnetic Fields: New Perspectives, Viraht Sahni, Xiao-Yin Pan

Publications and Research

The Schrödinger theory of electrons in an external electromagnetic field is described from the new perspective of the individual electron. The perspective is arrived at via the time-dependent "Quantal Newtonian" law (or differential virial theorem). (The time-independent law, a special case, provides a similar description of stationary-state theory). These laws are in terms of "classical" fields whose sources are quantal expectations of Hermitian operators taken with respect to the wave function. The laws reveal the following physics: (a) in addition to the external field, each electron experiences an internal field whose components are representative of a specific property of the …


Electron Correlations In An Excited State Of A Quantum Dot In A Uniform Magnetic Field, Marlina Slamet, Viraht Sahni Jan 2017

Electron Correlations In An Excited State Of A Quantum Dot In A Uniform Magnetic Field, Marlina Slamet, Viraht Sahni

Publications and Research

Electron correlations in a two-electron two-dimensional ‘artificial atom’ or quantum dot (with harmonic confining potential) in the presence of a uniform magnetic field in an excited singlet state are studied via quantal density functional theory (QDFT). QDFT allows for the separation of the electron correlations due to the Pauli exclusion principle and Coulomb repulsion, as well as the determination of the contribution of these correlations to the kinetic energy. The QDFT mapping is from the excited state of the quantum dot to one of noninteracting fermions in their ground state possessing the same basic variables of the density and physical …


Generalization Of The Schrödinger Theory Of Electrons, Viraht Sahni Jan 2017

Generalization Of The Schrödinger Theory Of Electrons, Viraht Sahni

Publications and Research

The Schrödinger theory for a system of electrons in the presence of both a static and time-dependent electromagnetic field is generalized so as to exhibit the intrinsic self-consistent nature of the corresponding Schrödinger equations. This is accomplished by proving that the Hamiltonian in the stationary-state and time-dependent cases {\hat{H}; \hat{H}(t)} are exactly known functionals of the corresponding wave functions {\Psi; \Psi(t)}, i.e. \hat{H} = \hat{H}[\Psi] and \hat{H}(t) = \hat{H}[\Psi(t)]. Thus, the Schrödinger equations may be written as \hat{H}[\Psi]\Psi = E[\Psi]\Psi and \hat{H}[\Psi(t)]\Psi(t) = i\partial\Psi(t)/\partial t. As a consequence the eiegenfunctions and energy eigenvalues {\Psi; E} of the stationary-state equation, and …


Rules And Mechanisms For Efficient Two-Stage Learning In Neural Circuits, Tiberiu Teşileanu, Bence Ölveczky, Vijay Balasubramanian Jan 2017

Rules And Mechanisms For Efficient Two-Stage Learning In Neural Circuits, Tiberiu Teşileanu, Bence Ölveczky, Vijay Balasubramanian

Publications and Research

Trial-and-error learning requires evaluating variable actions and reinforcing successful variants. In songbirds, vocal exploration is induced by LMAN, the output of a basal ganglia-related circuit that also contributes a corrective bias to the vocal output. This bias is gradually consolidated in RA, a motor cortex analogue downstream of LMAN. We develop a new model of such two-stage learning. Using stochastic gradient descent, we derive how the activity in ‘tutor’ circuits (e.g., LMAN) should match plasticity mechanisms in ‘student’ circuits (e.g., RA) to achieve efficient learning. We further describe a reinforcement learning framework through which the tutor can build its teaching …


Bulk Viscous Corrections To Screening And Damping In Qcd At High Temperatures, Qianqian Du, Adrian Dumitru, Yun Guo, Michael Strickland Jan 2017

Bulk Viscous Corrections To Screening And Damping In Qcd At High Temperatures, Qianqian Du, Adrian Dumitru, Yun Guo, Michael Strickland

Publications and Research

Non-equilibrium corrections to the distribution functions of quarks and gluons in a hot and dense QCD medium modify the “hard thermal loops” (HTL). The HTLs determine the retarded, advanced, and symmetric (time-ordered) propagators for gluons with soft momenta as well as the Debye screening and Landau damping mass scales. We compute such corrections to a thermal as well as to a non-thermal fixed point. The screening and damping mass scales are sensitive to the bulk pressure and hence to (pseudo-) critical dynamical scaling of the bulk viscosity in the vicinity of a second-order critical point. This could be reflected in …


Geodesic Merging, Konstantinos Georgatos Jan 2017

Geodesic Merging, Konstantinos Georgatos

Publications and Research

We pursue an account of merging through the use of geodesic semantics, the semantics based on the length of the shortest path on a graph. This approach has been fruitful in other areas of belief change such as revision and update. To this end, we introduce three binary merging operators of propositions defined on the graph of their valuations and we characterize them with a finite set of postulates. We also consider a revision operator defined in the extended language of pairs of propositions. This extension allows us to express all merging operators through the set of revision postulates.