1,396 research outputs found
Patterns-based Evaluation of Open Source BPM Systems: The Cases of jBPM, OpenWFE, and Enhydra Shark
In keeping with the proliferation of free software development initiatives and the increased interest in the business process management domain, many open source workflow and business process management systems have appeared during the last few years and are now under active development. This upsurge gives rise to two important questions: what are the capabilities of these systems? and how do they compare to each other and to their closed source counterparts? i.e. in other words what is the state-of-the-art in the area?. To gain an insight into the area, we have conducted an in-depth analysis of three of the major open source workflow management systems - jBPM, OpenWFE and Enhydra Shark, the results of which are reported here. This analysis is based on the workflow patterns framework and provides a continuation of the series of evaluations performed using the same framework on closed source systems, business process modeling languages and web-service composition standards. The results from evaluations of the three open source systems are compared with each other and also with the results from evaluations of three representative closed source systems - Staffware, WebSphere MQ and Oracle BPEL PM, documented in earlier works. The overall conclusion is that open source systems are targeted more toward developers rather than business analysts. They generally provide less support for the patterns than closed source systems, particularly with respect to the resource perspective which describes the various ways in which work is distributed amongst business users and managed through to completion
The CLIC Programme: Towards a Staged e+e- Linear Collider Exploring the Terascale : CLIC Conceptual Design Report
This report describes the exploration of fundamental questions in particle
physics at the energy frontier with a future TeV-scale e+e- linear collider
based on the Compact Linear Collider (CLIC) two-beam acceleration technology. A
high-luminosity high-energy e+e- collider allows for the exploration of
Standard Model physics, such as precise measurements of the Higgs, top and
gauge sectors, as well as for a multitude of searches for New Physics, either
through direct discovery or indirectly, via high-precision observables. Given
the current state of knowledge, following the observation of a 125 GeV
Higgs-like particle at the LHC, and pending further LHC results at 8 TeV and 14
TeV, a linear e+e- collider built and operated in centre-of-mass energy stages
from a few-hundred GeV up to a few TeV will be an ideal physics exploration
tool, complementing the LHC. In this document, an overview of the physics
potential of CLIC is given. Two example scenarios are presented for a CLIC
accelerator built in three main stages of 500 GeV, 1.4 (1.5) TeV, and 3 TeV,
together with operating schemes that will make full use of the machine capacity
to explore the physics. The accelerator design, construction, and performance
are presented, as well as the layout and performance of the experiments. The
proposed staging example is accompanied by cost estimates of the accelerator
and detectors and by estimates of operating parameters, such as power
consumption. The resulting physics potential and measurement precisions are
illustrated through detector simulations under realistic beam conditions.Comment: 84 pages, published as CERN Yellow Report
https://cdsweb.cern.ch/record/147522
CLE PERCOLATIONS
Conformal loop ensembles (CLEs) are random collections of loops in a simply connected domain, whose laws are characterized by a natural conformal invariance property. The set of points not surrounded by any loop is a canonical random connected fractal set — a random and conformally invariant analog of the Sierpinski carpet or gasket. In the present paper, we derive a direct relationship between the CLEs with simple loops (CLEκ for κ ∈ (8/3, 4), whose loops are Schramm’s SLEκ -type curves) and the corresponding CLEs with nonsimple loops (CLEκ 0 with κ 0 := 16/κ ∈ (4, 6), whose loops are SLEκ 0-type curves). This correspondence is the continuum analog of the Edwards–Sokal coupling between the q-state Potts model and the associated FK random cluster model, and its generalization to noninteger q. Like its discrete analog, our continuum correspondence has two directions. First, we show that for each κ ∈ (8/3, 4), one can construct a variant of CLEκ as follows: start with an instance of CLEκ 0 , then use a biased coin to independently color each CLEκ 0 loop in one of two colors, and then consider the outer boundaries of the clusters of loops of a given color. Second, we show how to interpret CLEκ 0 loops as interfaces of a continuum analog of critical Bernoulli percolation within CLEκ carpets — this is the first construction of continuum percolation on a fractal planar domain. It extends and generalizes the continuum percolation on open domains defined by SLE6 and CLE6. These constructions allow us to prove several conjectures made by the second author and provide new and perhaps surprising interpretations of the relationship between CLEs and the Gaussian free field. Along the way, we obtain new results about generalized SLEκ (ρ) curves for ρ < −2, such as their decomposition into collections of SLEκ -type ‘loops’ hanging off of SLEκ 0-type ‘trunks’, and vice versa (exchanging κ and κ 0 ). We also define a continuous family of natural CLE variants called boundary conformal loop ensembles (BCLEs) that share some (but not all) of the conformal symmetries that characterize CLEs, and that should be scaling limits of critical models with special boundary conditions. We extend the CLEκ /CLEκ 0 correspondence to a BCLEκ /BCLEκ 0 correspondence that makes sense for the wider range κ ∈ (2, 4] and κ 0 ∈ [4, 8).J.M.’s work was partially supported by DMS-1204894. S.S.’s work was also partially supported by a grant from the Simons Foundation and NSF grant DMS-1209044. W.W. acknowledges the support of SNF grant 155922, and the support of the Clay Foundation. W.W. is part of the NCCR Swissmap
On the set of normalized dilatations of fully-punctured pseudo-Anosov maps
We improve the bound on the number of tetrahedra in the veering triangulation
of a fully-punctured pseudo-Anosov mapping torus in terms of the normalized
dilatation. When the mapping torus has only one boundary component, we employ
various techniques to improve the bound further. Together with the author's
work with Hironaka in the case when the mapping torus has at least two boundary
components, this allows us to understand small elements of the set
of normalized dilatations of fully-punctured pseudo-Anosov maps
using computational means. In particular, we certify that the minimum element
of is and the minimum accumulation point of
is , where is the golden
ratio.Comment: 80 pages, 31 figure
Measurement of the branching fractions of the semileptonic decays B+ → ηlν and B+ → η′lν with signal-side only reconstruction at the Belle experiment
Diese Dissertation präsentiert eine Messung des Verzweigungsverhältnisses der Zerfälle
B+ → ηlν und B+ → η′lν. Dabei wird der gesamte an der Energie der Υ(4S)-Resonanz
gemessene Datensatz des Belle-Experiments verwendet. Dieser enthält 772E6 BB-Paare. Das
im Zerfall entstehende η-Meson wird in zwei und das η′-Meson in einem Zerfallskanal
rekonstruiert. Nur die Zerfallskette eines der beiden B-Mesonen wird explizit rekonstruiert,
wobei das Neutrino mittels Erhaltungssätzen aus dem Rest des Ereignisses abgeleitet wird.
Hiermit wird eine größtmögliche Rekonstruktionseffizienz erzielt. Der Anteil an
Untergrundereignissem im rekonstruierten Datensatz wird mittels Boosted Decision Trees
verringert, bevor die Anzahl an Signalereignissen im Datensatz mittels eines
Binned-Maximum-Likelihood-Fits ermittelt wird, bei dem die einzelnen MC Verteilungen an
den Datensatz gefittet werden. Die gesamte Analyse hält die Abhängigkeit der Selektion vom
Impulsübertrag q2 so gering wie möglich, um Auswirkungen der Zerfallsmodellierung zu
vermeiden. Die gemessenen Verzweigungsverhältnisse sind
Br(B+ → ηlν) = (2.83 ± 0.55 ± 0.34)E−5 und
Br(B+ → η′lν) = (2.79 ± 1.29 ± 0.30)E−5 mit statistischer und systematischer
Unsicherheit.This thesis presents a measurement of the branching fractions of the decays B+ → ηlν and
B+ → η'lν. The entire data sample collected by the Belle experiment at the energy of the
Υ(4S) resonance is used, which contains in total 772E6 BB pairs. The η meson is
reconstructed in two decay channels and the η′ meson in one decay channel. Only the decay
products of one of the two B mesons from the BB pair are explicitly reconstructed to achieve a
high efficiency. Instead of explicitly reconstructing the remainder of the event, the neutrino in
the decay is inferred using conservation laws to allow reconstruction of the B+. Background
events are reduced using boosted decision trees. A binned maximum likelihood fit of MC
distributions to the data sample is used to extract the signal yield in the end. The entire
reconstruction chain keeps the dependence on the transferred momentum q2 as low as possible
to reduce effects of the modelling of the decay. The determined branching fractions are
Br(B+ → ηlν) = (2.83 ± 0.55 ± 0.34)E−5 and
Br(B+ → η′lν) = (2.79 ± 1.29 ± 0.30)E−5 with the statistical uncertainty first and the
systematic second.2021-12-0
Sensitivity and background estimates towards Phase-I of the COMET muon-to-electron conversion search
COMET is a future high-precision experiment searching for charged lepton flavour violation through the muon-to-electron conversion process. It aims to push the intensity frontier of particle physics by coupling an intense muon beam with cutting-edge detector technology. The first stage of the experiment, COMET Phase-I, is currently being assembled and will soon enter its data acquisition period. It plans to achieve a single event sensitivity to μ-e conversion in aluminium of 3.1x10⁻¹⁵.
This thesis presents a study of the sensitivity and backgrounds of COMET Phase-I using the latest Monte Carlo simulation data produced. The background contribution from cosmic ray-induced atmospheric muons is estimated using a backward Monte Carlo approach, which allows computational resources to be focused on the most critical signal-mimicking events.
Analysis of a μ-e conversion simulation sample suggests that COMET Phase-I will reach a single event sensitivity of 3.6x10⁻¹⁵ within 146 days of data acquisition. Our results suggest that, in that period, on the order of 10³ atmospheric muons will enter the detector system and produce an event similar enough to the conversion signal to pass all the signal selection criteria. Most of these events will be rejected by the Cosmic Ray Veto system, however, we expect at least 2.2 background events to sneak in unnoticed. It is vital for the conversion search that these events be discriminated from conversion electrons, for instance by using Cherenkov threshold counters to distinguish between muons and electrons or, alternatively, by developing a direction identification algorithm to reject some fraction of the μ⁺-induced events.Open Acces
Statistical mechanics models in protein association problems
Doctor of PhilosophyDepartment of PhysicsJeremy D. SchmitProtein-Protein interactions can lead to disordered states such as precipitates or gels, or to ordered states such as crystals or microtubules. In order to study the different natures of protein-protein interactions we have developed statistical mechanics models in order to interpret the varied behavior of different protein systems. The main point will be to develop theoretical models that infer the time a length scales that characterize the dynamics of the systems analyzed. This approach seek to facilitate a connection to simulations and experiments, where a high resolution analysis in length and time is possible, since the theories can provide insights about the relevant time and length scales, and also about issues that can appear when studying these systems.
The first system studied is monoclonal antibodies in solution. Antibody solutions deviate from the dynamical and rheological response expected for globular proteins, especially as volume fraction is increased. Experimental evidence shows that antibodies can reversibly bind to each other via F[subscript]ab and F[subscript]c domains, and form larger structures (clusters) of several antibodies. Here we present a microscopic equilibrium model to account for the distribution of cluster sizes. Antibody clusters are modeled as polymers that can grow via reversible bonds either between two F[subscript]ab domains or between a F[subscript]ab and a F[subscript]c. We propose that the dynamical and rheological behavior is determined by molecular entanglements of the clusters. This entanglement does not occur at low concentrations where antibody-antibody binding contributes to the viscosity by increasing the effective size of the particles. The model explains the observed shear-thinning behavior of antibody solutions.
The second system is protein condensates inside living cells. Biomolecule condensates appear throughout the cell serving a wide variety of functions, but it is not clear how functional properties show in the concentrated network inside the condensate droplets. Here we model disordered proteins as linear polymers formed by "stickers" evenly spaced by "spacers". The spacing between stickers gives rise to different network toplogies inside the condensate droplet, determining distinguishing properties such us density and client binding.
The third system is protein-protein binding in a salt solutions. Biomolecular simulations are typically performed in an aqueous environment where the number of ions remains fixed for the duration of the simulation, generally with a number of salt pairs intended to match the macroscopic salt concentration. In contrast, real biomolecules experience local ion environments where the salt concentration is dynamic and may differ from bulk. We develop a statistical mechanics model to account for fluctuations of ions concentrations, and study how it affects the free energy of protein-protein binding
Development and validation of computational fluid dynamics models for the coupled simulation of heat transfer and fluid flow in the coral microenvironments
This thesis explored the temperature deviations between coral surface temperature and ambient seawater temperature that likely determines the microscale processes involved in coral bleaching. The work presented here applied Computational Fluid Dynamics (CFD) technique coupled with hydrodynamic modelling and ray-tracing to predict coral surface warming due to the effects of stressors. This thesis demonstrates that modelling microscale temperature could yield important insights into thermoregulation in corals, which may lead to a more effective reef management
- …