6,516 research outputs found
N=2 Supersymmetric Model with Dirac-Kahler Fermions from Generalized Gauge Theory in Two Dimensions
We investigate the generalized gauge theory which has been proposed
previously and show that in two dimensions the instanton gauge fixing of the
generalized topological Yang-Mills action leads to a twisted N=2 supersymmetric
action. We have found that the R-symmetry of N=2 supersymmetry can be
identified with the flavour symmetry of Dirac-Kahler fermion formulation. Thus
the procedure of twist allows topological ghost fields to be interpreted as the
Dirac-Kahler matter fermions.Comment: 22 pages, LaTe
Generalized Gauge Theories and Weinberg-Salam Model with Dirac-K\"ahler Fermions
We extend previously proposed generalized gauge theory formulation of
Chern-Simons type and topological Yang-Mills type actions into Yang-Mills type
actions. We formulate gauge fields and Dirac-K\"ahler matter fermions by all
degrees of differential forms. The simplest version of the model which includes
only zero and one form gauge fields accommodated with the graded Lie algebra of
supergroup leads Weinberg-Salam model. Thus the Weinberg-Salam model
formulated by noncommutative geometry is a particular example of the present
formulation.Comment: 33 pages, LaTe
Microscopic reversibility of quantum open systems
The transition probability for time-dependent unitary evolution is invariant
under the reversal of protocols just as in the classical Liouvillian dynamics.
In this article, we generalize the expression of microscopic reversibility to
externally perturbed large quantum open systems. The time-dependent external
perturbation acts on the subsystem during a transient duration, and
subsequently the perturbation is switched off so that the total system would
thermalize. We concern with the transition probability for the subsystem
between the initial and final eigenstates of the subsystem. In the course of
time evolution, the energy is irreversibly exchanged between the subsystem and
reservoir. The time reversed probability is given by the reversal of the
protocol and the initial ensemble. Microscopic reversibility equates the time
forward and reversed probabilities, and therefore appears as a thermodynamic
symmetry for open quantum systems.Comment: numerical demonstration is correcte
Photoinduced Magnetization in a Thin Fe-CN-Co Film
The magnetization of a thin Fe-Co cyanide film has been investigated from 5 K
to 300 K and in fields up to 500 G. Upon illumination with visible light, the
magnetization of the film rapidly increases. The original cluster glass
behavior is further developed in the photoinduced state and shows substantial
changes in critical temperature and freezing temperature.Comment: 2 pages, 2 figures, 1 table, International Conference on Magnetism
200
Note on Dirac--K\"ahler massless fields
We obtain the canonical and symmetrical Belinfante energy-momentum tensors of
Dirac--K\"{a}hler's fields. It is shown that the traces of the energy-momentum
tensors are not equal to zero. We find the canonical and Belinfante dilatation
currents which are not conserved, but a new conserved dilatation current is
obtained. It is pointed out that the conformal symmetry is broken. The
canonical quantization is performed and the propagator of the massless fields
in the first-order formalism is found.Comment: 16 pages, minor corrections in the text, published versio
Microscopic analysis of the microscopic reversibility in quantum systems
We investigate the robustness of the microscopic reversibility in open
quantum systems which is discussed by Monnai [arXiv:1106.1982 (2011)]. We
derive an exact relation between the forward transition probability and the
reversed transition probability in the case of a general measurement basis. We
show that the microscopic reversibility acquires some corrections in general
and discuss the physical meaning of the corrections. Under certain processes,
some of the correction terms vanish and we numerically confirmed that the
remaining correction term becomes negligible; the microscopic reversibility
almost holds even when the local system cannot be regarded as macroscopic.Comment: 12 pages, 10 figure
Twisted Superspace for N=D=2 Super BF and Yang-Mills with Dirac-K\"ahler Fermion Mechanism
We propose a twisted D=N=2 superspace formalism. The relation between the
twisted super charges including the BRST charge, vector and pseudo scalar super
charges and the N=2 spinor super charges is established. We claim that this
relation is essentially related with the Dirac-K\"ahler fermion mechanism. We
show that a fermionic bilinear form of twisted N=2 chiral and anti-chiral
superfields is equivalent to the quantized version of BF theory with the Landau
type gauge fixing while a bosonic bilinear form leads to the N=2 Wess-Zumino
action. We then construct a Yang-Mills action described by the twisted N=2
chiral and vector superfields, and show that the action is equivalent to the
twisted version of the D=N=2 super Yang-Mills action, previously obtained from
the quantized generalized topological Yang-Mills action with instanton gauge
fixing.Comment: 36 page
SPATIAL EFFECTS: 3D MOVEMENT OF A VIRTUAL SOUND SOURCE
This document intends to explain the audio development project proposed to emulate the spatial effect of having a sound source moving in a 3D sonic environment. Throughout this document the reader will see a detailed explanation of how the problem was approached, the specific requirements needed to achieve the result, how this requirements were implemented using MatLab coding and how the end product was tested to evaluate the effectiveness of the solution provided. MatLab files will also be provided so that the reader can associate the concepts being described in order to have a better understanding of the process followed to develop this application.Architecture & Allied Art
Improving Clinical Practice Using Clinical Decision Support Systems: A Systematic Review of Trials to Identify Features Critical to Success
Objective To identify features of clinical decision support systems critical for improving clinical practice. Design Systematic review of randomised controlled trials. Data sources Literature searches via Medline, CINAHL, and the Cochrane Controlled Trials Register up to 2003; and searches of reference lists of included studies and relevant reviews. Study selection Studies had to evaluate the ability of decision support systems to improve clinical practice. Data extraction Studies were assessed for statistically and clinically significant improvement in clinical practice and for the presence of 15 decision support system features whose importance had been repeatedly suggested in the literature. Results Seventy studies were included. Decision support systems significantly improved clinical practice in 68% of trials. Univariate analyses revealed that, for five of the system features, interventions possessing the feature were significantly more likely to improve clinical practice than interventions lacking the feature. Multiple logistic regression analysis identified four features as independent predictors of improved clinical practice: automatic provision of decision support as part of clinician workflow (P \u3c 0.00001), provision of recommendations rather than just assessments (P = 0.0187), provision of decision support at the time and location of decision making (P = 0.0263), and computer based decision support (P = 0.0294). Of 32 systems possessing all four features, 30 (94%) significantly improved clinical practice. Furthermore, direct experimental justification was found for providing periodic performance feedback, sharing recommendations with patients, and requesting documentation of reasons for not following recommendations. Conclusions Several features were closely correlated with decision support systems\u27 ability to improve patient care significantly. Clinicians and other stakeholders should implement clinical decision support systems that incorporate these features whenever feasible and appropriate
A method for segregation of speech signals
International audienc
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