18,162 research outputs found
The uniting of Europe and the foundation of EU studies: revisiting the neofunctionalism of Ernst B. Haas
This article suggests that the neofunctionalist theoretical legacy left by Ernst B. Haas is somewhat richer and more prescient than many contemporary discussants allow. The article develops an argument for routine and detailed re-reading of the corpus of neofunctionalist work (and that of Haas in particular), not only to disabuse contemporary students and scholars of the normally static and stylized reading that discussion of the theory provokes, but also to suggest that the conceptual repertoire of neofunctionalism is able to speak directly to current EU studies and comparative regionalism. Neofunctionalism is situated in its social scientific context before the theory's supposed erroneous reliance on the concept of 'spillover' is discussed critically. A case is then made for viewing Haas's neofunctionalism as a dynamic theory that not only corresponded to established social scientific norms, but did so in ways that were consistent with disciplinary openness and pluralism
Probing the Light Pseudoscalar Window
Very light pseudoscalars can arise from the symmetry-breaking sector in many
extensions of the Standard Model. If their mass is below 200 MeV, they can be
long-lived and have interesting phenomenology. We discuss the experimental
constraints on several models with light pseudoscalars, including one in which
the pseudoscalar is naturally fermiophobic. Taking into account the stringent
bounds from rare K and B decays, we find allowed parameter space in each model
that may be accessible in direct production experiments. In particular, we
study the photoproduction of light pseudoscalars at Jefferson Lab and conclude
that a beam dump experiment could explore some of the allowed parameter space
of these models.Comment: 22 pages, 4 figure
Installation Induced Stresses For Grouted Roof Bolts
The judicious use of roof bolts in stabilizing underground openings necessitates the ability to determine the state of stress in and around such bolts. A method of modeling a system of roof bolts is presented. This method is then applied in the determination of the state of stress due to bolt tightening. Two specific roof bolt configurations are considered: a fully grouted post-tensioned bolt and a post-tensioned bolt with grouted-end anchorage. The analysis showed that the grout annulus transferred nearly all of the bolt load 3nto the rock within a distance of 12 hole diameters from the point of bolt load application. © 1976
A Practical, Secure, and Verifiable Cloud Computing for Mobile Systems
Cloud computing systems, in which clients rent and share computing resources
of third party platforms, have gained widespread use in recent years.
Furthermore, cloud computing for mobile systems (i.e., systems in which the
clients are mobile devices) have too been receiving considerable attention in
technical literature. We propose a new method of delegating computations of
resource-constrained mobile clients, in which multiple servers interact to
construct an encrypted program known as garbled circuit. Next, using garbled
inputs from a mobile client, another server executes this garbled circuit and
returns the resulting garbled outputs. Our system assures privacy of the mobile
client's data, even if the executing server chooses to collude with all but one
of the other servers. We adapt the garbled circuit design of Beaver et al. and
the secure multiparty computation protocol of Goldreich et al. for the purpose
of building a secure cloud computing for mobile systems. Our method
incorporates the novel use of the cryptographically secure pseudo random number
generator of Blum et al. that enables the mobile client to efficiently retrieve
the result of the computation, as well as to verify that the evaluator actually
performed the computation. We analyze the server-side and client-side
complexity of our system. Using real-world data, we evaluate our system for a
privacy preserving search application that locates the nearest bank/ATM from
the mobile client. We also measure the time taken to construct and evaluate the
garbled circuit for varying number of servers, demonstrating the feasibility of
our secure and verifiable cloud computing for mobile systems
Interplay of size and Landau quantizations in the de Haas-van Alphen oscillations of metallic nanowires
We examine the interplay between size quantization and Landau quantization in
the De Haas-Van Alphen oscillations of clean, metallic nanowires in a
longitudinal magnetic field for `hard' boundary conditions, i.e. those of an
infinite round well, as opposed to the `soft' parabolically confined boundary
conditions previously treated in Alexandrov and Kabanov (Phys. Rev. Lett. {\bf
95}, 076601 (2005) (AK)). We find that there exist {\em two} fundamental
frequencies as opposed to the one found in bulk systems and the three
frequencies found by AK with soft boundary counditions. In addition, we find
that the additional `magic resonances' of AK may be also observed in the
infinite well case, though they are now damped. We also compare the numerically
generated energy spectrum of the infinite well potential with that of our
analytic approximation, and compare calculations of the oscillatory portions of
the thermodynamic quantities for both models.Comment: Title changed, paper streamlined on suggestion of referrees, typos
corrected, numerical error in figs 2 and 3 corrected and final result
simplified -- two not three frequencies (as in the previous version) are
observed. Abstract altered accordingly. Submitted to Physical Review
Who Can Deviate from the Party Line? Political Ideology Moderates Evaluation of Incongruent Policy Positions in Insula and Anterior Cingulate Cortex
Political polarization at the elite level is a major concern in many contemporary democracies, which is argued to alienate large swaths of the electorate and prevent meaningful social change from occurring, yet little is known about how individuals respond to political candidates who deviate from the party line and express policy positions incongruent with their party affiliations. This experiment examines the neural underpinnings of such evaluations using functional MRI (fMRI). During fMRI, participants completed an experimental task where they evaluated policy positions attributed to hypothetical political candidates. Each block of trials focused on one candidate (Democrat or Republican), but all participants saw two candidates from each party in a randomized order. On each trial, participants received information about whether the candidate supported or opposed a specific policy issue. These issue positions varied in terms of congruence between issue position and candidate party affiliation. We modeled neural activity as a function of incongruence and whether participants were viewing ingroup or outgroup party candidates. Results suggest that neural activity in brain regions previously implicated in both evaluative processing and work on ideological differences (insula and anterior cingulate cortex) differed as a function of the interaction between incongruence, candidate type (ingroup versus outgroup), and political ideology. More liberal participants showed greater activation to incongruent versus congruent trials in insula and ACC, primarily when viewing ingroup candidates. Implications for the study of democratic representation and linkages between citizensâ calls for social change and policy implementation are discussed
Nyquist method for Wigner-Poisson quantum plasmas
By means of the Nyquist method, we investigate the linear stability of
electrostatic waves in homogeneous equilibria of quantum plasmas described by
the Wigner-Poisson system. We show that, unlike the classical Vlasov-Poisson
system, the Wigner-Poisson case does not necessarily possess a Penrose
functional determining its linear stability properties. The Nyquist method is
then applied to a two-stream distribution, for which we obtain an exact,
necessary and sufficient condition for linear stability, as well as to a
bump-in-tail equilibrium.Comment: 6 figure
Phase diagram of hot magnetized two-flavor color superconducting quark matter
A two-flavor color superconducting (2SC) Nambu--Jona-Lasinio (NJL) model is
introduced at finite temperature T, chemical potential mu and in the presence
of a constant magnetic field eB. The effect of (T,mu,eB) on the formation of
chiral and color symmetry breaking condensates is studied. The complete phase
portrait of the model in T-mu, mu-eB, and T-eB phase spaces for various fixed
eB, T, and mu is explored. A threshold magnetic field eB_t~ 0.5 GeV^2 is found
above which the dynamics of the system is solely dominated by the lowest Landau
level (LLL) and the effects of T and mu are partly compensated by eB.Comment: V1: 29 pages, 15 figures, 3 tables. V2: Discussions improved. Version
accepted for publication in PR
The suppression of superconductivity in MgCNi3 by Ni-site doping
The effects of partial substitution of Cu and Co for Ni in the intermetallic
perovskite superconductor MgCNi3 are reported. Calculation of the expected
electronic density of states suggests that electron (Cu) and hole (Co) doping
should have different effects. For MgCNi3-xCux, solubility of Cu is limited to
approximately 3% (x = 0.1), and Tc decreases systematically from 7K to 6K. For
MgCNi3-xCox, solubility of Co is much more extensive, but bulk
superconductivity disappears for Co doping of 1% (x = 0.03). No signature of
long range magnetic ordering is observed in the magnetic susceptibility of the
Co doped material.Comment: submitted, Solid State Communication
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