431 research outputs found
NRQCD Results on Form Factors
We report results on and semi-leptonic decay form factors using
NRQCD. We investigate scaling behavior of decay amplitudes. For
Effect of higher order relativistic correction terms are also studied.Comment: 9 pgs. 10 figures. Latex2e. espcrc2.sty included. Talk presented at
the Internatioal Workshop "LATTICE QCD ON PARALLEL COMPUTERS", March 1997,
Tsukub
Heavy quark mass dependence of semileptonic form factors for B decays
We present our study of the dependence of the heavy-to-light semileptonic B
decay form factors on the heavy-light meson mass . Simulations are made
over a range of the heavy quark mass covering both the charm and bottom quarks
using the -improved clover action at on a and
lattice. We find that a weak dependence of form factors on
observed in previous studies in the region of charm quark persists up
to the region of quark. The soft pion relation is
examined and found to be largely violated.Comment: 3 pages, latex source-file, 4 figures as epsf-file, uses espcrc2.sty.
Talk presented by S. Tominaga at Lattice 97, Edinburgh, Scotland, 22-26 Jul
199
Gauge Theories on a 2+2 Anisotropic Lattice
The implementation of gauge theories on a four-dimensional anisotropic
lattice with two distinct lattice spacings is discussed, with special attention
to the case where two axes are finely and two axes are coarsely discretized.
Feynman rules for the Wilson gauge action are derived and the renormalizability
of the theory and the recovery of the continuum limit are analyzed. The
calculation of the gluon propagator and the restoration of Lorentz invariance
in on-shell states is presented to one-loop order in lattice perturbation
theory for on both 2+2 and 3+1 lattices.Comment: 27 pages, uses feynmf. Font compatibility adjuste
Victim-offender mediation and social work: focus groups with mediators in Flanders
The role of social work in the restorative justice field remains largely unexplored. This article reports on the findings of focus groups conducted with mediators of juvenile and adult mediation practices in Flanders (Belgium) to gain more insight into how mediators perceive their professional role and to what extent they refer to individual and structural dimensions of social work practice. Implications for future social work involvement and research are made
Potential Models for Radiative Rare B Decays
We compute the branching ratios for the radiative rare decays of B into
K-Meson states and compare them to the experimentally determined branching
ratio for inclusive decay b -> s gamma using non relativistic quark model, and
form factor definitions consistent with HQET covariant trace formalism. Such
calculations necessarily involve a potential model. In order to test the
sensitivity of calculations to potential models we have used three different
potentials, namely linear potential, screening confining potential and heavy
quark potential as it stands in QCD.We find the branching ratios relative to
the inclusive b ->s gamma decay to be (16.07\pm 5.2)% for B -> K^* (892)gamma
and (7.25\pm 3.2)% for B -> K_2^* (1430)gamma for linear potential. In the case
of the screening confining potential these values are (19.75\pm 5.3)% and
(4.74\pm 1.2)% while those for the heavy quark potential are (11.18\pm 4.6)%
and (5.09\pm 2.7)% respectively. All these values are consistent with the
corresponding present CLEO experimental values: (16.25\pm 1.21)% and (5.93\pm
0.46)%.Comment: RevTeX, 6 pages, 1 eps figur
QCD Sum Rule Analysis of the Decays and
We use QCD sum rules to calculate the hadronic matrix elements governing the
rare decays and induced by
the flavour changing neutral current transition. We also study
relations among semileptonic and rare decay form factors. The
analysis of the invariant mass distribution of the lepton pair in and of the angular asymmetry in provides us with interesting tests of the Standard Model and its
extensions.Comment: 26 pages REVTEX + 7 figures. Some typos corrected, figure 5 and 7
modified. This version will appear on Physical Review
The transition form factors for semi-leptonic weak decays of in QCD sum rules
Within the Standard Model, we investigate the semi-leptonic weak decays of
. The various form factors of transiting to a single charmed
meson () are studied in the framework of the QCD sum rules.
These form factors fully determine the rates of the weak semi-leptonic decays
of and provide valuable information about the non-perturbative QCD
effects. Our results indicate that the decay rate of the semi-leptonic weak
decay mode is at order of .Comment: 28 pages, 6 figures, revised version to be published in Eur.Phys.J.
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Federal Emergency Management Information System (FEMIS) Bill of Materials (BOM) for FEMIS Version 1.3
This document describes the Bill of Materials (BOM) for the Federal Emergency Management Information System (FEMIS) for version 1.3. FEMIS runs on a client/server platform consisting of a UNIX system, employed as a data server, and personal computers (PCs) using the Windows NT operating system. Servers and PCs require the operating system, utility software, communications and other internal cards that are also listed in the following sections. FEMIS will support the use of Commercial Off-The-Shelf (COTS) software applications and tools. Several configurations are possible at a Chemical Stockpile Emergency Preparedness Program (CSEPP) site. In this description, a site is understood to be compromised of several installations, including the depot, surrounding Immediate Response Zone (IRZ) and Protective Action Zone (PAZ) counties, and one or more state Emergency Operations Centers (EOCs). In general, the main differences between possible configurations are the number of users at an installation, the location of the UNIX data server(s), and wide area network (WAN) link between installations. The number of PC workstations will vary between installations
Passerine Birds Breeding under Chronic Noise Experience Reduced Fitness
Background
Fitness in birds has been shown to be negatively associated with anthropogenic noise, but the underlying mechanisms remain obscure. It is however crucial to understand the mechanisms of how urban noise impinges on fitness to obtain a better understanding of the role of chronic noise in urban ecology. Here, we examine three hypotheses on how noise might reduce reproductive output in passerine birds: (H1) by impairing mate choice, (H2) by reducing territory quality and (H3) by impeding chick development.
Methodology/Principal Findings
We used long-term data from an island population of house sparrows, Passer domesticus, in which we can precisely estimate fitness. We found that nests in an area affected by the noise from large generators produced fewer young, of lower body mass, and fewer recruits, even when we corrected statistically for parental genetic quality using a cross-fostering set-up, supporting H3. Also, individual females provided their young with food less often when they bred in the noisy area compared to breeding attempts by the same females elsewhere. Furthermore, we show that females reacted flexibly to increased noise levels by adjusting their provisioning rate in the short term, which suggests that noise may be a causal factor that reduces reproductive output. We rejected H1 and H2 because nestbox occupancy, parental body mass, age and reproductive investment did not differ significantly between noisy and quiet areas.
Conclusions/Significance
Our results suggest a previously undescribed mechanism to explain how environmental noise can reduce fitness in passerine birds: by acoustically masking parent–offspring communication. More importantly, using a cross-fostering set-up, our results demonstrate that birds breeding in a noisy environment experience significant fitness costs. Chronic noise is omnipresent around human habitation and may produces similar fitness consequences in a wide range of urban bird species
Demystifying image-based machine learning: a practical guide to automated analysis of field imagery using modern machine learning tools
Image-based machine learning methods are becoming among the most widely-used forms of data analysis across science, technology, engineering, and industry. These methods are powerful because they can rapidly and automatically extract rich contextual and spatial information from images, a process that has historically required a large amount of human labor. A wide range of recent scientific applications have demonstrated the potential of these methods to change how researchers study the ocean. However, despite their promise, machine learning tools are still under-exploited in many domains including species and environmental monitoring, biodiversity surveys, fisheries abundance and size estimation, rare event and species detection, the study of animal behavior, and citizen science. Our objective in this article is to provide an approachable, end-to-end guide to help researchers apply image-based machine learning methods effectively to their own research problems. Using a case study, we describe how to prepare data, train and deploy models, and overcome common issues that can cause models to underperform. Importantly, we discuss how to diagnose problems that can cause poor model performance on new imagery to build robust tools that can vastly accelerate data acquisition in the marine realm. Code to perform analyses is provided at https://github.com/heinsense2/AIO_CaseStudy
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