13,793 research outputs found
Queer Theory in the Metal Music Scene: How These Cultures Influence Each Other
Queer theory has existed in the metal music scene since its beginning. In this paper, many aspects of both topics are dissected. Focusing on metal fashion and its crossover into queer armor, Queer coding, and its translation to metal archetypes on television. And the analysis of queer comfortability in metal music spaces by using queer theory as it applies to mass cultures and subcultur
Field Quantization, Photons and Non-Hermitean Modes
Field quantization in three dimensional unstable optical systems is treated
by expanding the vector potential in terms of non-Hermitean (Fox-Li) modes in
both the cavity and external regions. The cavity non-Hermitean modes (NHM) are
treated using the paraxial and monochromaticity approximations. The NHM
bi-orthogonality relationships are used in a standard canonical quantization
procedure based on introducing generalised coordinates and momenta for the
electromagnetic (EM) field. The quantum EM field is equivalent to a set of
quantum harmonic oscillators (QHO), associated with either the cavity or the
external region NHM. This confirms the validity of the photon model in unstable
optical systems, though the annihilation and creation operators for each QHO
are not Hermitean adjoints. The quantum Hamiltonian for the EM field is the sum
of non-commuting cavity and external region contributions, each of which is sum
of independent QHO Hamiltonians for each NHM, but the external field
Hamiltonian also includes a coupling term responsible for external NHM photon
exchange processes. Cavity energy gain and loss processes is associated with
the non-commutativity of cavity and external region operators, given in terms
of surface integrals involving cavity and external region NHM functions on the
cavity-external region boundary. The spontaneous decay of a two-level atom
inside an unstable cavity is treated using the essential states approach and
the rotating wave approximation. Atomic transitions leading to cavity NHM
photon absorption have a different coupling constant to those leading to photon
emission, a feature resulting from the use of NHM functions. Under certain
conditions the decay rate is enhanced by the Petermann factor.Comment: 38 pages, tex, 2 figures, ps. General expression for decay rate
added. To be published in Journal of Modern Optic
A water-poverty accounting framework: analyzing the water-poverty link
Water use, Water poverty, Water management, Irrigation water, Case studies, Thailand
Poverty and Aspirations Failure
We develop a theoretical framework to study the psychology of poverty and 'aspirations failure'. In our framework, the rich and the poor share the same preferences - and also a behavioral bias in setting aspirations. Greater downside risks imposed by poverty exacerbates the effects of this behavioral bias: the poor are more susceptible to both an aspirations failure and pessimism about the likelihood of achieving success. Poverty limits the set of people whose life experiences the poor consider relevant for forming their own beliefs and aspirations. Mitigating behavioral poverty traps require policies which go beyond reducing material deprivation.Reference-dependent Preferences;Aspirations;Persistent Poverty;Locus of control;Simillarity and Belief Formation
Optimal Clustering under Uncertainty
Classical clustering algorithms typically either lack an underlying
probability framework to make them predictive or focus on parameter estimation
rather than defining and minimizing a notion of error. Recent work addresses
these issues by developing a probabilistic framework based on the theory of
random labeled point processes and characterizing a Bayes clusterer that
minimizes the number of misclustered points. The Bayes clusterer is analogous
to the Bayes classifier. Whereas determining a Bayes classifier requires full
knowledge of the feature-label distribution, deriving a Bayes clusterer
requires full knowledge of the point process. When uncertain of the point
process, one would like to find a robust clusterer that is optimal over the
uncertainty, just as one may find optimal robust classifiers with uncertain
feature-label distributions. Herein, we derive an optimal robust clusterer by
first finding an effective random point process that incorporates all
randomness within its own probabilistic structure and from which a Bayes
clusterer can be derived that provides an optimal robust clusterer relative to
the uncertainty. This is analogous to the use of effective class-conditional
distributions in robust classification. After evaluating the performance of
robust clusterers in synthetic mixtures of Gaussians models, we apply the
framework to granular imaging, where we make use of the asymptotic
granulometric moment theory for granular images to relate robust clustering
theory to the application.Comment: 19 pages, 5 eps figures, 1 tabl
Design of an integrated shallow water wave experiment
The experimental design and instrumentation for an integrated shallow-water surface gravity wave experiment is discussed. The experiment required the measurement of the water surface elevation, meteorological parameters, and directional spectra at a number of locations on a shallow lake. In addition, to acquire data under a wide range of conditions, an experimental period of three years was required. A system of telephone and radio modem links were installed to enable real-time monitoring of instrument performance at eight separate measurement locations on the lake. This system also enabled logging sessions to be optimized to ensure the maximum possible data return from this extended experimentIEEE Oceanic Engineering Societ
Brownian ratchet in a thermal bath driven by Coulomb friction
The rectification of unbiased fluctuations, also known as the ratchet effect,
is normally obtained under statistical non-equilibrium conditions. Here we
propose a new ratchet mechanism where a thermal bath solicits the random
rotation of an asymmetric wheel, which is also subject to Coulomb friction due
to solid-on-solid contacts. Numerical simulations and analytical calculations
demonstrate a net drift induced by friction. If the thermal bath is replaced by
a granular gas, the well known granular ratchet effect also intervenes,
becoming dominant at high collision rates. For our chosen wheel shape the
granular effect acts in the opposite direction with respect to the
friction-induced torque, resulting in the inversion of the ratchet direction as
the collision rate increases. We have realized a new granular ratchet
experiment where both these ratchet effects are observed, as well as the
predicted inversion at their crossover. Our discovery paves the way to the
realization of micro and sub-micrometer Brownian motors in an equilibrium
fluid, based purely upon nano-friction.Comment: main paper: 4 pages and 4 figures; supplemental material joined at
the end of the paper; a movie of the experiment can be viewed
http://www.youtube.com/watch?v=aHrdY4BC71k ; all the material has been
submitted for publication [new version with substantial changes in the order
of the presentation of the results; differences with previous works have been
put in evidence
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