7,012 research outputs found
Preventing Incomplete/Hidden Requirements: Reflections on Survey Data from Austria and Brazil
Many software projects fail due to problems in requirements engineering (RE).
The goal of this paper is analyzing a specific and relevant RE problem in
detail: incomplete/hidden requirements. We replicated a global family of RE
surveys with representatives of software organizations in Austria and Brazil.
We used the data to (a) characterize the criticality of the selected RE
problem, and to (b) analyze the reported main causes and mitigation actions.
Based on the analysis, we discuss how to prevent the problem. The survey
includes 14 different organizations in Austria and 74 in Brazil, including
small, medium and large sized companies, conducting both, plan-driven and agile
development processes. Respondents from both countries cited the
incomplete/hidden requirements problem as one of the most critical RE problems.
We identified and graphically represented the main causes and documented
solution options to address these causes. Further, we compiled a list of
reported mitigation actions. From a practical point of view, this paper
provides further insights into common causes of incomplete/hidden requirements
and on how to prevent this problem.Comment: in Proceedings of the Software Quality Days, 201
Two-color QCD with staggered fermions at finite temperature under the influence of a magnetic field
In this paper we investigate the influence of a constant external magnetic
field on the finite-temperature phase structure and the chiral properties of a
simplified lattice model for QCD. We assume an SU(2) gauge symmetry and employ
dynamical staggered fermions of identical mass without rooting, corresponding
to Nf=4 flavors of identical electric charge. For fixed mass (given in lattice
units) the critical temperature is seen to rise with the magnetic field
strength. For three fixed beta-values, selected such that we stay (i) within
the chirally broken phase, (ii) within the transition region or (iii) within
the chirally restored phase, we study the approach to the chiral limit for
various values of the magnetic field. Within the chirally broken (confinement)
phase the chiral condensate is found to increase monotonically with a growing
magnetic field strength. In the chiral limit the increase starts linear in
agreement with a chiral model studied by Shushpanov and Smilga. Within the
chirally restored (deconfinement) phase the chiral condensate tends to zero in
the chiral limit, irrespective of the strength of the magnetic field.Comment: 15 pages, 12 figures; version accepted by Physical Review
New proton polarized structure functions in charged current processes at HERA
Estimates for longitudinal spin asymmetries which single out new polarized
nucleon structure functions in deeply inelastic charged current interactions at
HERA energies are given, exploiting their interpretation in terms of polarized
quark distributions. These asymmetries turn out to be large and allow a
measurement of the new polarized structure functions and ,
which would add valuable tests and information on the spin content of quarks
inside a polarized proton. We also show that single spin asymmetries in neutral
current interactions are very small.Comment: LaTeX, 8 pages, 6 figure
On Evidence-based Risk Management in Requirements Engineering
Background: The sensitivity of Requirements Engineering (RE) to the context
makes it difficult to efficiently control problems therein, thus, hampering an
effective risk management devoted to allow for early corrective or even
preventive measures. Problem: There is still little empirical knowledge about
context-specific RE phenomena which would be necessary for an effective
context- sensitive risk management in RE. Goal: We propose and validate an
evidence-based approach to assess risks in RE using cross-company data about
problems, causes and effects. Research Method: We use survey data from 228
companies and build a probabilistic network that supports the forecast of
context-specific RE phenomena. We implement this approach using spreadsheets to
support a light-weight risk assessment. Results: Our results from an initial
validation in 6 companies strengthen our confidence that the approach increases
the awareness for individual risk factors in RE, and the feedback further
allows for disseminating our approach into practice.Comment: 20 pages, submitted to 10th Software Quality Days conference, 201
Metastable Pores at the Onset of Constant-Current Electroporation
Single metastable nanopores, appearing before the actual electroporation under constant-current conditions, are used to characterize the onset of electroporation. Unlike the long-lived electropores typical of the current controlled methods, these pores survive for milliseconds and observing them is possible due to slow development of electroporation, provided by the gradual accumulation of charges on a planar membrane. Analysis of the metastable pore appearance frequency and lifetime shows the first introductory stage of electroporation. During this stage two species of metastable pores open, the majority of very low conductance that seem not fully developed as hydrophilic electropores. The experiments reveal that voltage value defines the electroporation onset while the current value affects the rate of electroporation. Membrane capacitance has a great impact on the membrane susceptibility to the pore appearance, related to its thickness and integrity. Pores of nonperfect membranes appear more easily, but they do not live any longer than others
Complete Draft Genome Sequence of the Actinobacterium Nocardiopsis sinuspersici UTMC102 (DSM 45277T), Which Produces Serine Protease.
Tokovenko B, Rückert C, Kalinowski J, et al. Complete Draft Genome Sequence of the Actinobacterium Nocardiopsis sinuspersici UTMC102 (DSM 45277T), Which Produces Serine Protease. Genome Announc. 2017;5(20): e00362-17.The genome sequence of alkalohalophilic actinobacterium Nocardiopsis sinuspersici UTMC102 is provided. N. sinuspersici UTMC102 produces a highly active serine alkaline protease, and contains at least 11 gene clusters encoding the biosynthesis of secondary metabolites. The N. sinuspersici UTMC102 genome was assembled into a single chromosomal scaffold
Heavy MSSM Higgs Bosons at CMS: "LHC wedge" and Higgs-Mass Precision
The search for MSSM Higgs bosons will be an important goal at the LHC. In
order to analyze the search reach of the CMS experiment for the heavy neutral
MSSM Higgs bosons, we combine the latest results for the CMS experimental
sensitivities based on full simulation studies with state-of-the-art
theoretical predictions of MSSM Higgs-boson properties. The experimental
analyses are done assuming an integrated luminosity of 30 or 60 fb^-1. The
results are interpreted as 5 \si discovery contours in MSSM M_A-tan_beta
benchmark scenarios. Special emphasis is put on the variation of the Higgs
mixing parameter mu. While the variation of mu can shift the prospective
discovery reach (and correspondingly the ``LHC wedge'' region) by about Delta
tan_beta= 10, the discovery reach is rather stable with respect to the impact
of other supersymmetric parameters. Within the discovery region we analyze the
accuracy with which the masses of the heavy neutral Higgs bosons can be
determined. An accuracy of 1-4% should be achievable, depending on M_A and
tan_beta.Comment: Talk given by G.W. at EPS07 (Manchester, July 2007) and talk given by
S.H. at SUSY07 (Karlsruhe, July 2007). 4 pages, 2 figure
Adaptive Boolean Networks and Minority Games with Time--Dependent Capacities
In this paper we consider a network of boolean agents that compete for a
limited resource. The agents play the so called Generalized Minority Game where
the capacity level is allowed to vary externally. We study the properties of
such a system for different values of the mean connectivity of the network,
and show that the system with K=2 shows a high degree of coordination for
relatively large variations of the capacity level.Comment: 4 pages, 4 figure
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