58,196 research outputs found
Solving QCD evolution equations in rapidity space with Markovian Monte Carlo
This work covers methodology of solving QCD evolution equation of the parton
distribution using Markovian Monte Carlo (MMC) algorithms in a class of models
ranging from DGLAP to CCFM. One of the purposes of the above MMCs is to test
the other more sophisticated Monte Carlo programs, the so-called Constrained
Monte Carlo (CMC) programs, which will be used as a building block in the
parton shower MC. This is why the mapping of the evolution variables (eikonal
variable and evolution time) into four-momenta is also defined and tested. The
evolution time is identified with the rapidity variable of the emitted parton.
The presented MMCs are tested independently, with ~0.1% precision, against the
non-MC program APCheb especially devised for this purpose.Comment: version compatible with with the erratum in Acta Physica Polonic
Break-up fragments excitation and the freeze-out volume
We investigate, in microcanonical multifragmentation models, the influence of
the amount of energy dissipated in break-up fragments excitation on freeze-out
volume determination. Assuming a limiting temperature decreasing with nuclear
mass, we obtain for the Xe+Sn at 32 MeV/nucleon reaction [J. D. Frankland et
al., Nucl. Phys. A689, 905 (2001); A689, 940 (2001)] a freeze-out volume almost
half the one deduced using a constant limiting temperature.Comment: 11 pages, 6 figure
Neuroevolution of Humanoids that Walk Further and Faster with Robust Gaits
Bipedal locomotion requires precise rhythm and balance. Here we demonstrate two fitness-function enhancements applied to OpenAI?s 3D Humanoid-v1 walking task using a replica of Salimans et al.?s evolution strategy (Salimans et al., 2017). The first enhancement reduces control cost, following a start-up period, and the second enhancement penalises poor balance. Individually, each enhancement results in improved gaits and doubles both median speed and median distance walked. Combining the two enhancements results in little further improvement in the absence of noise but is shown to produce gaits that are much more robust to noise in their actions, with median speed, distance and time two to five times those of the default and individual-enhancement gaits at an intermediate noise level
Isabelle/DOF. User and Implementation Manual
The software for which this is the manual is available via the DOI in this recordIsabelle/DOF provides an implementation of DOF on top of Isabelle/HOL. DOF itself is a
novel framework for defining ontologies and enforcing them during document development
and document evolution. Isabelle/DOF targets use-cases such as mathematical texts referring to a theory development or technical reports requiring a particular structure. A major
application of DOF is the integrated development of formal certification documents (e.g.,
for Common Criteria or CENELEC 50128) that require consistency across both formal and
informal arguments.
Isabelle/DOF is integrated into Isabelle’s IDE, which allows for smooth ontology development as well as immediate ontological feedback during the editing of a document. Its checking
facilities leverage the collaborative development of documents required to be consistent with
an underlying ontological structure.
In this user-manual, we give an in-depth presentation of the design concepts of DOF’s Ontology Definition Language (ODL) and describe comprehensively its major commands. Many
examples show typical best-practice applications of the system. Isabelle/DOF is the first ontology language supporting machine-checked links between the formal and informal parts in
an LCF-style interactive theorem proving environment.IRT System
Kinetic energy spectra for fragments and break-up density in multifragmentation
We investigate the possibility, in nuclear fragmentation, to extract
information on nuclear density at break-up from fragment kinetic energy spectra
using a simultaneous scenario for fragment emission. The conclusions we derive
are different from the recently published results of Viola et al. [Phys. Rev.
Lett. 93, (2004), 132701] assuming a sequential fragment emission and claiming
that the experimentally observed decrease of peak centroids for kinetic energy
spectra of fragments with increasing bombarding energy is due to a monotonic
decrease of the break-up density.Comment: 6 pages, 3 figure
Perinatal outcome in patients with pre-eclampsia at the university of maiduguri teaching hospital, Nigeria
Pre-eclampsia, a common maternal disease in pregnancy is an important cause of perinatal morbidity and mortality especially in developing countries. Objectives: To determine the perinatal outcome of patients with pre-eclampsia in our environment. Methods: A retrospective review of the perinatal outcome of patients with pre-eclampsia managed at the University of Maiduguri Teaching Hospital from January 2005 to June 2007. Logistic regression analysis was used to determine sociodemographic and obstetrics factors that are independently associated with perinatal mortality in these patients. Results: During the study period, there were 84 cases of preeclampsia and 3,560 deliveries giving a pre-eclampsia prevalence of 2.36%. Sixty-nine cases (82.1%) were available for review. The mean booking diastolic blood pressure of the study group was 78.6±15.7 mmHg. Majority of the patients 55(79.7%) were in the age group 19-35 years and 33(47.8%) were primigravidae. In 36(52.2%) of the cases, the birth weight of the babies was <2.5 Kg and IUGR was diagnosed in 37(53.6%). There were 16 perinatal death giving a perinatal mortality rate of 262/1000 live birth. IUGR (OR=11.35, 95%CI=2.06-62.55, p=0.005) and diagnosis of PE at a gestational age <32 weeks (OR=3.39, 95%CI=1.09-10.55, p=0.04) were found to be independently associated with perinatal mortality in patients with preeclampsia. Conclusion: Pre-eclampsia is associated with adverse perinatal outcome, with early onset disease and IUGR being independently associated with an increase risk of perinatal mortality
System and market failures: the unavailability of magnesium sulphate for the treatment of eclampsia and pre-eclampsia in Mozambique and Zimbabwe.
Low cost and effective drugs, such as magnesium sulphate, need to be included in initiatives to improve access to essential medicines in Afric
A Taylor method for numerical solution of generalized pantograph equations with linear functional argument
AbstractThis paper is concerned with a generalization of a functional differential equation known as the pantograph equation which contains a linear functional argument. In this paper, we introduce a numerical method based on the Taylor polynomials for the approximate solution of the pantograph equation with retarded case or advanced case. The method is illustrated by studying the initial value problems. The results obtained are compared by the known results
Anticipation and transfer of expert pattern perception
Conference Theme: Meeting New Challenges and Bridging Cultural Gaps in Sport and Exercise PsychologyINTRODUCTION: When an observer views a moving object that is abruptly halted, the human perceptual system continues to extrapolate the object’s movement, predicting it’s likely pathway and misrepresenting the final stopping point as being further along the original trajectory (Freyd & Johnson, 1987). This extrapolation of the temporal features is typically referred to as “representational momentum” (Freyd, 1987; Freyd & Finke, 1984; Intraub, 2002). It has been suggested that this phenomenon occurs because participants anticipate the trajectory of the object and remember that object by integrating its predicted motion with perceptions of its implied acceleration and velocity (Didierjean & Marmèche, 2005; Finke, Freyd, & Shyi, 1986). This anticipatory trace is then stored in memory and can be accessed for subsequent recall and recognition …postprin
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