1,212 research outputs found
Entwurf eines Frameworks für CTI-Lösungen im Call Center
Besonders in Call Centern spielt die unter dem Begriff CTI (Computer Telephony Integration) zusammengefasste Integration von IT-Systemen und Telefonanlagen eine wichtige Rolle. Wenn auch diese Integration auf technischer Ebene in der Regel zufriedenstellend gelöst wird, zeigt ein Blick auf die Softwareentwicklung in diesem Bereich noch Nachholbedarf. Die vorliegende Arbeit greift dieses Problem auf und versucht, den Ansatz CTI auf die Ebene der Entwicklung verteilter Anwendungen abzubilden. Ziel dabei ist es, Erkenntnisse darüber zu erzielen, inwieweit ein allgemeines Basismodell als Framework für die Entwicklung von CTI-Anwendungen definiert werden kann und welchen Mehrwert es mit sich bringt. Parallel dazu wird die Frage untersucht, inwieweit bewährte Methoden und Technologien verteilter Systeme auf diesem Spezialgebiet ihre Anwendung finden können. Dazu wird ein allgemeines Anwendungsmodell für CTI-Lösungen und darauf aufbauend ein objektorientiertes, verteiltes Framework entworfen. Das Framework selbst wird als Prototyp implementiert und diversen Leistungsmessungen unterzogen.Computer Telephony Integration (CTI) plays an important role wherever computer and telecommunication systems have to interact. Applications in a call center are typical examples. This integration has been studied widely from a technical viewpoint only, but not at the level of application development. Since telecommunication systems are naturally distributed systems, CTI eventually leads to distributed applications. This thesis presents an example of a general, object-oriented framework for CTI applications and examines the use of proven technologies and methodologies for distributed applications. Based on a prototype implementation the practicability of the concept is being examined and verified
On The Expected Photon Spectrum in B -> X_s + gamma and Its Uses
Measuring the photon energy spectrum in radiative B decays provides essential
help for gaining theoretical control over semileptonic B transitions. The
hadronic recoil mass distribution in B -> X_u \ell\nu promises the best
environment for determining |V_ub|. The theoretical uncertainties are largest
in the domain of low values of the lepton pair mass q^2. Universality relations
allow to describe this domain reliably in terms of the photon spectrum in B ->
X_s + \gamma. A method is proposed to incorporate 1/m_b corrections into this
relation. The low-E_\gamma tail in radiative decays is important in the context
of extracting |V_ub|. We argue that CLEO's recent fit to the spectrum
underestimates the fraction of the photon spectrum below 2 GeV. Potentially
significant uncertainties enter in the theoretical evaluation of the integrated
end-point lepton spectrum or the B -> X_u \ell\nu width with a too high value
of the lower cut on q^2 in alternative approaches to |V_ub|.Comment: 24 pages, 6 figures, LaTeX. Revised: Complete version. Numerical
predictions are improved and the estimate for the decay fraction revised. The
theoretical expectations for the decay fraction and the spectrum itself are
given on the plot
Algebras of Toeplitz operators on the n-dimensional unit ball
We study -algebras generated by Toeplitz operators acting on the standard weighted Bergman space over the unit ball in . The symbols of generating operators are assumed to be of a certain product type, see (\ref{Introduction_form_of_the_symbol}). By choosing and in different function algebras and over lower dimensional unit balls and , respectively, and by assuming the invariance of under some torus action we obtain -algebras whose structural properties can be described. In the case of -quasi-radial functions and bounded uniformly continuous
or vanishing oscillation symbols we describe the structure of elements from the algebra , derive a list of irreducible
representations of , and prove completeness of this list in some cases. Some of these representations originate from a ``quantization effect'', induced
by the representation of as the direct sum of Bergman spaces over a lower dimensional unit ball with growing weight parameter. As an application we derive the
essential spectrum and index formulas for matrix-valued operators
Uniform continuity and quantization on bounded symmetric domains
We consider Toeplitz operatorsTλfwith symbolfacting on the standard weighted Bergmanspaces over a bounded symmetric domain Ω⊂Cn.Hereλ>genus−1 is the weight parameter.The classical asymptotic relation for the semi-commutatorlimλ→∞∥∥∥TλfTλg−Tλfg∥∥∥λ=0,withf,g∈C(Bn),(∗)where Ω =Bndenotes the complex unit ball, is extended to larger classes of bounded andunbounded operator symbol-functions and to more general domains. We deal with operatorsymbols that generically are neither continuous inside Ω nor admit a continuous extension to theboundary. Letβdenote the Bergman metric distance function on Ω. We prove that(∗) remainstrue forfandgin the space UC(Ω) of allβ-uniformly continuous functions on Ω. Note that thisspace contains also unbounded functions. In case of the complex unit ball Ω =Bn⊂Cnwe showthat(∗) holds true for bounded symbols in VMO(Bn), where the vanishing oscillation insideBnismeasured with respect toβ.Atthesametime(∗) fails for generic bounded measurable symbols.We construct a corresponding counterexample using oscillating symbols that are continuousoutside of a single point in
Anomalous f_1 exchange in vector meson photoproduction asymmetries
We perform an analysis of the elastic production of vector mesons with
polarized photon beams at high energy in order to investigate the validity of a
recently proposed dynamical mechanism based on the dominance of the f_1
trajectory at large momentum transfer. The density matrix characterizing the
angular distributions of the vector meson decays is calculated within an
exchange model which includes the Pomeron and the f_1. The asymmetries of these
decays turn out to be very useful to disentangle the role of these exchanges
since their effect depends crucially on their quantum numbers which are
different. The observables analyzed are accessible with present experimental
facilities.Comment: 10 pages, REVTeX, 4 figures, some figures are corrected, conclusions
unchange
Towards Higgs boson production in gluon fusion to NNLO in the MSSM
We consider the Higgs boson production in the gluon-fusion channel to
next-to-next-to-leading order within the Minimal Supersymmetric Standard Model.
In particular, we present analytical results for the matching coefficient of
the effective theory and study its influence on the total production cross
section in the limit where the masses of all MSSM particles coincide. For
supersymmetric masses below 500 GeV it is possible to find parameters leading
to a significant enhancement of the Standard Model cross section, the
-factors, however, change only marginally.Comment: 20 pages; v2: modification of discussion of numerical effect, version
to appear in EPJC; v3: eq.(18) corrected, minor correction
Large introns in relation to alternative splicing and gene evolution: a case study of Drosophila bruno-3
Background:
Alternative splicing (AS) of maturing mRNA can generate structurally and functionally distinct transcripts from the same gene. Recent bioinformatic analyses of available genome databases inferred a positive correlation between intron length and AS. To study the interplay between intron length and AS empirically and in more detail, we analyzed the diversity of alternatively spliced transcripts (ASTs) in the Drosophila RNA-binding Bruno-3 (Bru-3) gene. This gene was known to encode thirteen exons separated by introns of diverse sizes, ranging from 71 to 41,973 nucleotides in D. melanogaster. Although Bru-3's structure is expected to be conducive to AS, only two ASTs of this gene were previously described.
Results:
Cloning of RT-PCR products of the entire ORF from four species representing three diverged Drosophila lineages provided an evolutionary perspective, high sensitivity, and long-range contiguity of splice choices currently unattainable by high-throughput methods. Consequently, we identified three new exons, a new exon fragment and thirty-three previously unknown ASTs of Bru-3. All exon-skipping events in the gene were mapped to the exons surrounded by introns of at least 800 nucleotides, whereas exons split by introns of less than 250 nucleotides were always spliced contiguously in mRNA. Cases of exon loss and creation during Bru-3 evolution in Drosophila were also localized within large introns. Notably, we identified a true de novo exon gain: exon 8 was created along the lineage of the obscura group from intronic sequence between cryptic splice sites conserved among all Drosophila species surveyed. Exon 8 was included in mature mRNA by the species representing all the major branches of the obscura group. To our knowledge, the origin of exon 8 is the first documented case of exonization of intronic sequence outside vertebrates.
Conclusion:
We found that large introns can promote AS via exon-skipping and exon turnover during evolution likely due to frequent errors in their removal from maturing mRNA. Large introns could be a reservoir of genetic diversity, because they have a greater number of mutable sites than short introns. Taken together, gene structure can constrain and/or promote gene evolution
The state of the Martian climate
60°N was +2.0°C, relative to the 1981–2010 average value (Fig. 5.1). This marks a new high for the record. The average annual surface air temperature (SAT) anomaly for 2016 for land stations north of starting in 1900, and is a significant increase over the previous highest value of +1.2°C, which was observed in 2007, 2011, and 2015. Average global annual temperatures also showed record values in 2015 and 2016. Currently, the Arctic is warming at more than twice the rate of lower latitudes
Supersymmetric next-to-next-to-leading order corrections to Higgs boson production in gluon fusion
We compute the total cross section for the production of a light CP even
Higgs boson within the framework of supersymmetric QCD up to
next-to-next-to-leading order. Technical subtleties in connection to the
evaluation of three-loop Feynman integrals with many mass scales are discussed
in detail and explicit results for the counterterms of the evanescent couplings
are provided. The new results are applied to several phenomenological scenarios
which are in accordance with the recent discovery at the LHC. In a large part
of the still allowed parameter space the factor of the supersymmetric
theory is close to the one of the Standard Model. However, for the case where
one of the top squarks is light, a deviation of more than 5% in the
next-to-next-to-leading order prediction of the cross section can be observed
where at the same time the predicted Higgs boson mass has a value of about 125
GeV.Comment: 37 page
Geophysical and atmospheric evolution of habitable planets
The evolution of Earth-like habitable planets is a complex process that depends on the geodynamical and geophysical environments. In particular, it is necessary that plate tectonics remain active over billions of years. These geophysically active environments are strongly coupled to a planet's host star parameters, such as mass, luminosity and activity, orbit location of the habitable zone, and the planet's initial water inventory. Depending on the host star's radiation and particle flux evolution, the composition in the thermosphere, and the availability of an active magnetic dynamo, the atmospheres of Earth-like planets within their habitable zones are differently affected due to thermal and nonthermal escape processes. For some planets, strong atmospheric escape could even effect the stability of the atmosphere
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