241 research outputs found
Two Applications of High Order Methods: Wave Propagation and Accelerator Physics
Numerical simulations of partial differential equations (PDE) are used to predict the behavior of complex physics phenomena when the real life experiments are expensive. Discretization of a PDE is the representation of the continuous problem as a discrete problem that can be solved on a computer. The discretization always introduces a certain inaccuracy caused by the numerical approximation. By increasing the computational cost of the numerical algorithm the solution can be computed more accurately. In the theory of numerical analysis this fact is called the convergence of the numerical algorithm. The idea behind high order methods is to improve the rate of convergence so a slight increase of numerical work will lead to a significant increase of accuracy. We consider the wave equation on the domain around the body of a complex shape. This problem is challenging since because of the geometrical complexity. In this work we propose the Hybrid Hermite-Discontinuous Galerkin method of the overset grids for the wave equation. It combines highly efficient Hermite methods acting on Cartesian grids with the Discontinuous Galerkin method acting on a curvilinear grid around the body. The results of long time simulation will be presented to demonstrate the high order accuracy and stability of the proposed method. High energy particle physicists would like polarized electron beams in the next generation of circular particle accelerators. The so-called DK formulas predict well the level of polarization at current energies but they may not be valid at the higher energies of the next generation machines. We aim the check the validity of the formulas and extend them if needed by numerically integrating the so-called full Bloch equation. This is a system of PDEs which is more fundamental than the DK formulas and is believed to contain all the relevant physics. The full Bloch equations can be classified as an advection-diffusion problem in 3 degrees of freedom which is an enormous problem to solve on the computer. Our idea is to use the fast Fourier transform for the angular dimensions and introduce the parallel in Fourier modes numerical algorithm. The results of numerical simulation for a one degree of freedom and a two degrees of freedom model circular accelerator will be presented
Android Permissions Remystified: A Field Study on Contextual Integrity
Due to the amount of data that smartphone applications can potentially
access, platforms enforce permission systems that allow users to regulate how
applications access protected resources. If users are asked to make security
decisions too frequently and in benign situations, they may become habituated
and approve all future requests without regard for the consequences. If they
are asked to make too few security decisions, they may become concerned that
the platform is revealing too much sensitive information. To explore this
tradeoff, we instrumented the Android platform to collect data regarding how
often and under what circumstances smartphone applications are accessing
protected resources regulated by permissions. We performed a 36-person field
study to explore the notion of "contextual integrity," that is, how often are
applications accessing protected resources when users are not expecting it?
Based on our collection of 27 million data points and exit interviews with
participants, we examine the situations in which users would like the ability
to deny applications access to protected resources. We found out that at least
80% of our participants would have preferred to prevent at least one permission
request, and overall, they thought that over a third of requests were invasive
and desired a mechanism to block them
The Feasibility of Dynamically Granted Permissions: Aligning Mobile Privacy with User Preferences
Current smartphone operating systems regulate application permissions by
prompting users on an ask-on-first-use basis. Prior research has shown that
this method is ineffective because it fails to account for context: the
circumstances under which an application first requests access to data may be
vastly different than the circumstances under which it subsequently requests
access. We performed a longitudinal 131-person field study to analyze the
contextuality behind user privacy decisions to regulate access to sensitive
resources. We built a classifier to make privacy decisions on the user's behalf
by detecting when context has changed and, when necessary, inferring privacy
preferences based on the user's past decisions and behavior. Our goal is to
automatically grant appropriate resource requests without further user
intervention, deny inappropriate requests, and only prompt the user when the
system is uncertain of the user's preferences. We show that our approach can
accurately predict users' privacy decisions 96.8% of the time, which is a
four-fold reduction in error rate compared to current systems.Comment: 17 pages, 4 figure
Подвійна природа політичних ринків: чи підриває це демократію?
This article is an attempt to analyze the contradictions of political marketing as a theory and technology. Various
aspects of scholarly debate analyzed and various problems associated with application of political marketing are
highlighted. У статті проаналізовано суперечливу природу політичного маркетингу як теорії та технології. Також розглянуто різні аспекти
цих суперечностей і різні проблеми, пов’язані із застосуванням політичного маркетингу
Theoretical Approaches to the Concept of Legal Relations
A state governed by the rule of law establishes balanced legal relations. This article describes four scientific and theoretical approaches to the concept of legal relations, i.e., legal, subject-object, moral, and socio-psychological. According to the legal approach, legal relations are regulated by law. The subject-object approach defines legal relations as those that occur between subjects who possess certain rights and exercise them in relation to each other or to the objects in the legal field. According to the moral approach, society builds the system of law based on moral principles. This approach offers a step-by-step formation of law in the process of social development. Stage 1 shapes moral norms as a result of direct communication between community members. Stage 2 is associated with the individual assimilation of norms and the formation of morality. Stage 3 presupposes the arrival of legal norms. Stage 4 ends with the legislative consolidation of legal norms. The theoretical analysis revealed four socio-psychological processes in the development of legal norms: a) informal interpersonal communication yields moral norms, b) moral behavior patterns become internal, and moral consciousness appears; c) moral norms are exteriorized in the public consciousness, thus leading to legal consciousness; d) moral norms are legitimized, and legal norms become law. The socio-psychological approach considers such principles of legal relations as the sense of justice and equality
American Government (UWG)
This Grants Collection for American Government was created under a Round Four ALG Textbook Transformation Grant.
Affordable Learning Georgia Grants Collections are intended to provide faculty with the frameworks to quickly implement or revise the same materials as a Textbook Transformation Grants team, along with the aims and lessons learned from project teams during the implementation process.
Documents are in .pdf format, with a separate .docx (Word) version available for download. Each collection contains the following materials: Linked Syllabus Initial Proposal Final Reporthttps://oer.galileo.usg.edu/polisci-collections/1001/thumbnail.jp
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