6,541 research outputs found
Weak Matrix Elements without Quark Masses on the Lattice
We introduce a new parameterization of four-fermion matrix elements which
does not involve quark masses and thus allows a reduction of systematic
uncertainties in physical amplitudes. As a result the apparent quadratic
dependence of e'/e on m_s is removed. To simplify the matching between lattice
and continuum renormalization schemes, we express our results in terms of
Renormalization Group Invariant B-parameters which are renormalization-scheme
and scale independent. As an application of our proposal, matrix elements of
DeltaI=3/2 and SUSY DeltaF=2 (F=S,C,B) four-fermion operators have been
computed.Comment: Invited talk at QCD Euroconference 99, 4 pages BUHEP-99-2
Estimation of the control parameter from symbolic sequences: Unimodal maps with variable critical point
The work described in this paper can be interpreted as an application of the
order patterns of symbolic dynamics when dealing with unimodal maps.
Specifically, it is shown how Gray codes can be used to estimate the
probability distribution functions (PDFs) of the order patterns of parametric
unimodal maps. Furthermore, these PDFs depend on the value of the parameter,
what eventually provides a handle to estimate the parameter value from symbolic
sequences (in form of Gray codes), even when the critical point depends on the
parameter.Comment: 10 pages, 14 figure
Derivation of diagnostic models based on formalized process knowledge
© IFAC.Industrial systems are vulnerable to faults. Early and accurate detection and diagnosis in production systems can minimize down-time, increase the safety of the plant operation, and reduce manufacturing costs. Knowledge- and model-based approaches to automated fault detection and diagnosis have been demonstrated to be suitable for fault cause analysis within a broad range of industrial processes and research case studies. However, the implementation of these methods demands a complex and error-prone development phase, especially due to the extensive efforts required during the derivation of models and their respective validation. In an effort to reduce such modeling complexity, this paper presents a structured causal modeling approach to supporting the derivation of diagnostic models based on formalized process knowledge. The method described herein exploits the Formalized Process Description Guideline VDI/VDE 3682 to establish causal relations among key-process variables, develops an extension of the Signed Digraph model combined with the use of fuzzy set theory to allow more accurate causality descriptions, and proposes a representation of the resulting diagnostic model in CAEX/AutomationML targeting dynamic data access, portability, and seamless information exchange
Maximum Likelihood Estimation and Graph Matching in Errorfully Observed Networks
Given a pair of graphs with the same number of vertices, the inexact graph
matching problem consists in finding a correspondence between the vertices of
these graphs that minimizes the total number of induced edge disagreements. We
study this problem from a statistical framework in which one of the graphs is
an errorfully observed copy of the other. We introduce a corrupting channel
model, and show that in this model framework, the solution to the graph
matching problem is a maximum likelihood estimator. Necessary and sufficient
conditions for consistency of this MLE are presented, as well as a relaxed
notion of consistency in which a negligible fraction of the vertices need not
be matched correctly. The results are used to study matchability in several
families of random graphs, including edge independent models, random regular
graphs and small-world networks. We also use these results to introduce
measures of matching feasibility, and experimentally validate the results on
simulated and real-world networks
Use of Myofascial Release and Proprioceptive Neuromuscular Facilitation in Combination with a Rehabilitation Protocol for a Patient following a Massive Rotator Cuff Tear and Repair: A Case Report
Background and Purpose. This case report describes the use of postoperative treatments incorporating myofascial release and proprioceptive neuromuscular techniques, on a 59-year-old male who underwent a left open rotator cuff repair following a massive rotator cuff tear. This was after an 8 week passive motion phase. The goals of this case report were to evaluate the feasibility of these techniques and to examine improvements in shoulder range of motion, function of the involved extremity, and pain reduction.
Case Description. The patient suffered a massive rotator cuff tear at work after falling on his shoulder. The patient started with an 8 week passive motion treatment phase combined with stretching to protect the surgical sites and allow the rotator cuff tendons to heal. At 8 weeks the patient started an active assistive range of motion treatment phase to work on strengthening and flexibility. At 10 weeks he was able to do active range of motion and began strength exercises to help strengthen the deltoid and rotator cuff muscles.
Intervention. Myofascial release was used to stretch out tight restrictive tissues. The patient also performed a proprioceptive neuromuscular facilitation (PNF) hold-relax technique for external rotation.
Outcomes. Visual analog pain scores (0-10) at examination, 8 weeks, and 12 weeks were 6, 3, and 1, respectively. Passive shoulder flexion, abduction, and external rotation increased by 95°,55° and 40°, respectively. At 12 weeks the patient was able to do some overhead activities at 90 degrees and was able to put on and take off his coat.
Discussion. The findings suggest that myofascial release and a PNF hold-relax technique may be incorporated into a rehabilitation program for a rotator cuff tear and repair
Real-time Quantum evolution in the Classical approximation and beyond
With the goal in mind of deriving a method to compute quantum corrections for
the real-time evolution in quantum field theory, we analyze the problem from
the perspective of the Wigner function. We argue that this provides the most
natural way to justify and extend the classical approximation. A simple
proposal is presented that can allow to give systematic quantum corrections to
the evolution of expectation values and/or an estimate of the errors committed
when using the classical approximation. The method is applied to the case of a
few degrees of freedom and compared with other methods and with the exact
quantum results. An analysis of the dependence of the numerical effort involved
as a function of the number of variables is given, which allow us to be
optimistic about its applicability in a quantum field theoretical context.Comment: 32 pages, 6 figure
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