9,595 research outputs found
Charge breaking bounds in the Zee model
We study the possibility that charge breaking minima occur in the Zee model.
We reach very different conclusions from those attained in simpler, two Higgs
doublet models, and the reason for this is traced back to the existence of
cubic terms in the potential. A scan of the Zee model's parameter space shows
that CB is restricted to a narrow region of values of the parameters
DC-Prophet: Predicting Catastrophic Machine Failures in DataCenters
When will a server fail catastrophically in an industrial datacenter? Is it
possible to forecast these failures so preventive actions can be taken to
increase the reliability of a datacenter? To answer these questions, we have
studied what are probably the largest, publicly available datacenter traces,
containing more than 104 million events from 12,500 machines. Among these
samples, we observe and categorize three types of machine failures, all of
which are catastrophic and may lead to information loss, or even worse,
reliability degradation of a datacenter. We further propose a two-stage
framework-DC-Prophet-based on One-Class Support Vector Machine and Random
Forest. DC-Prophet extracts surprising patterns and accurately predicts the
next failure of a machine. Experimental results show that DC-Prophet achieves
an AUC of 0.93 in predicting the next machine failure, and a F3-score of 0.88
(out of 1). On average, DC-Prophet outperforms other classical machine learning
methods by 39.45% in F3-score.Comment: 13 pages, 5 figures, accepted by 2017 ECML PKD
INFLUENCE OF CELL WALL CALCIUM CONTENT IN FRUIT FIRMNESS DURING THE RIPENING OF PLUMS (PRUNUS DOMESTICA L.).
‘Rainha Claudia Verde’ is a regional cultivar of Prunus domestica L. well adapted to a specific region in the south of Portugal. In order to understand the postharvest behavior of this cultivar produced in different orchards, cell wall poly-saccharides and cell wall calcium fruit content were studied during ripening in two consecutive years. During harvest period pectic fractions soluble in water, carbonate and KOH were prepared from alcohol-insoluble residue (AIR) of plums. Galacturonic and neutral sugars contents were measured during fruit ripening and fruit firmness was also evaluated. The calcium fruit level was determined in the AIR during harvest season as well as in dry matter. Fruit firmness was significantly higher in the second year and was probably related with calcium fruit content and pectic polysaccharides. There was a significant difference in calcium fruit content between orchards, and this might influence the overall fruit texture during the postharvest period. During fruit ripening water soluble pectic polysaccharides did not change significantly, which corresponded with the small decrease in tissue firmness. The occurrence in the supernatant of the cellulosic residue of highly branched polysaccharides might be the consequence of matrix material associated with microfibrilar phase. Depolymerization of the hemicellulosic fraction was not evident during plum ripening. The loss of fruit firmness is a consequence of many cellular events which are influenced by external factors. The knowledge of calcium content in the cell wall and the pectic poly¬saccharides could be of great importance to local farmers to predict fruit texture
Retraction methods and fixed point free maps with null minimal displacements on unit ball
In this paper we consider the class of H\"older-Lipschitz maps on unit ball
of a Banach space , and the question we deal with is whether for any
and there exists a fixed-point free map such that for all and . We show that if has a spreading
Schauder basis then such a map can always be built, answering a question posed
by the first author in \cite{Bar}. In the general case, using a recent approach
of R. Medina \cite{M} concerning H\"older retractions of -flat closed
convex sets, we show that for any decreasing null sequence , there exists a fixed-point free mapping on so that
for all and
. New results related to Lipschitz maps are also obtained.Comment: Comments welcom
Influence of oxygen supply on the susceptibility of cv. Palomino fino must to browning
Experiments have been conducted on the oxidation of must (cv. Palomino fine). At the initial decanting process prior to fermentation, wines produced from hyperoxidized must had a reduced content of oxidable polyphenolic compounds and a reduced tendency to browning; they maintained these characteristics after bottling. Intermediate doses and the combined use of oxygen and sulphur dioxide were not fully effective in resolving the problem of browning for must of this grape variety, The larger the dose of oxygen (30 mg.l-1), the less the content of hydroxycinnamic esters and the lower the oxidizability, This dose was appropriate for producing a "fino" sherry wine with a low tendency to browning, retaining the sensory characteristics of this particular type of wine
Single Stellar Populations in the Near-Infrared - I. Preparation of the IRTF spectral stellar library
We present a detailed study of the stars of the IRTF spectral library to
understand its full extent and reliability for use with Stellar Population (SP)
modeling. The library consist of 210 stars, with a total of 292 spectra,
covering the wavelength range of 0.94 to 2.41 micron at a resolution R = 2000.
For every star we infer the effective temperature (Teff), gravity (logg) and
metallicity ([Z/Zsun]) using a full-spectrum fitting approach in a section of
the K band (2.19 to 2.34 micron) and temperature-NIR colour relations. We test
the flux calibration of these stars by calculating their integrated colours and
comparing them with the Pickles library colour-temperature relations. We also
investigate the NIR colours as a function of the calculated effective
temperature and compared them in colour-colour diagrams with the Pickles
library. This latter test shows a good broad-band flux calibration, important
for the SP models. Finally, we measure the resolution R as a function of
wavelength. We find that the resolution increases as a function of lambda from
about 6 angstrom in J to 10 angstrom in the red part of the K-band. With these
tests we establish that the IRTF library, the largest currently available
general library of stars at intermediate resolution in the NIR, is an excellent
candidate to be used in stellar population models. We present these models in
the next paper of this series.Comment: 17 pages, 19 figures. Accepted for publication in Astronomy and
Astrophysic
BDGS: A Scalable Big Data Generator Suite in Big Data Benchmarking
Data generation is a key issue in big data benchmarking that aims to generate
application-specific data sets to meet the 4V requirements of big data.
Specifically, big data generators need to generate scalable data (Volume) of
different types (Variety) under controllable generation rates (Velocity) while
keeping the important characteristics of raw data (Veracity). This gives rise
to various new challenges about how we design generators efficiently and
successfully. To date, most existing techniques can only generate limited types
of data and support specific big data systems such as Hadoop. Hence we develop
a tool, called Big Data Generator Suite (BDGS), to efficiently generate
scalable big data while employing data models derived from real data to
preserve data veracity. The effectiveness of BDGS is demonstrated by developing
six data generators covering three representative data types (structured,
semi-structured and unstructured) and three data sources (text, graph, and
table data)
Recognition of the epidemiological significance of Neisseria meningitidis capsular serogroup W135 in the Rio de Janeiro region, Brazil
Neisseria meningitidis retains its ability to cause endemic and hiperendemic disease in human population living in any environment, as well as localized outbreaks and massive epidemics in civilians and military personnel. In Rio de Janeiro it has been reported in the 1990s as prolonged outbreak of serogroup B and at least one epidemic of serogroup C was well defined, both demanding quick action by the Public Health authorities. We report here the emergence of serogroup W135 meningococcal disease causing endemic and case cluster in Rio de Janeiro during the first years of this new century
Inelaticity in hadron-nucleus collisions from emulsion chamber studies
The inelasticity of hadron-carbon nucleus collisions in the energy region
exceeding 100 TeV is estimated from the carbon-emulsion chamber data at Pamirs
to be . When combined with the recently presented data on
hadron-lead nucleus collisions taken at the same energy range it results in the
mass number dependence of inelasticity. The evaluated partial
inelasticity for secondary () interactions, ,
suggests that the second and higher interactions of the excited hadron inside
the nucleus proceed with only slight energy losses.Comment: LaTeX file and 5 LaTeX files with figures, 11 pages altogether.
Thoroughly rewritten and modified, one figure addded one removed. To be
published in Phys. Rev.
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