Search results for " 4"
showing 10 items of 3131 documents
La utopía correctora: A propòsit del mite d'El polític de Plató
2014
[spa] Cal entendre la narració del mite de l'Edat de Cronos en El polític de Plató en el marc on esta situada. Sera aleshores que es podra comprendre com Plató va compasar els diferents materials que hi inteiVenen per aconseguir neutralitzar la creen~a que aquella edat d'or era una situació óptima.
Hydrography and food distribution during a tidal cycle above a cold-water coral mound
2022
Cold-water corals (CWCs) are important ecosystem engineers in the deep sea that provide habitat for numerous species and can form large coral mounds. These mounds influence surrounding currents and induce distinct hy- drodynamic features, such as internal waves and episodic downwelling events that accelerate transport of organic matter towards the mounds, supplying the corals with food. To date, research on organic matter distribution at coral mounds has focussed either on seasonal timescales or has provided single point snapshots. Data on food distribution at the timescale of a diurnal tidal cycle is currently limited. Here, we integrate physical, biogeochemical, and biological data throug…
Studies of the performance of the ATLAS detector using cosmic-ray muons
2011
Muons from cosmic-ray interactions in the atmosphere provide a high-statistics source of particles that can be used to study the performance and calibration of the ATLAS detector. Cosmic-ray muons can penetrate to the cavern and deposit energy in all detector subsystems. Such events have played an important role in the commissioning of the detector since the start of the installation phase in 2005 and were particularly important for understanding the detector performance in the time prior to the arrival of the first LHC beams. Global cosmic-ray runs were undertaken in both 2008 and 2009 and these data have been used through to the early phases of collision data-taking as a tool for calibrat…
Measurement of inclusive jet and dijet cross sections in proton-proton collisions at 7 TeV centre-of-mass energy with the ATLAS detector
2011
Jet cross sections have been measured for the first time in proton-proton collisions at a centre-of-mass energy of 7 TeV using the ATLAS detector. The measurement uses an integrated luminosity of 17 nb−1 recorded at the Large Hadron Collider. The anti-k t algorithm is used to identify jets, with two jet resolution parameters, R=0.4 and 0.6. The dominant uncertainty comes from the jet energy scale, which is determined to within 7% for central jets above 60 GeV transverse momentum. Inclusive single-jet differential cross sections are presented as functions of jet transverse momentum and rapidity. Dijet cross sections are presented as functions of dijet mass and the angular variable χ. The res…
Measurements of underlying-event properties using neutral and charged particles in pp collisions at root s=900 GeV and root s=7 TeV with the ATLAS de…
2011
We present first measurements of charged and neutral particle-flow correlations in pp collisions using the ATLAS calorimeters. Data were collected in 2009 and 2010 at centre-of-mass energies of 900 GeV and 7 TeV. Events were selected using a minimum-bias trigger which required a charged particle in scintillation counters on either side of the interaction point. Particle flows, sensitive to the underlying event, are measured using clusters of energy in the ATLAS calorimeters, taking advantage of their fine granularity. No Monte Carlo generator used in this analysis can accurately describe the measurements. The results are independent of those based on charged particles measured by the ATLAS …
Luminosity determination in pp collisions at s=7 TeV using the ATLAS detector at the LHC
2011
Measurements of luminosity obtained using the ATLAS detector during early running of the Large Hadron Collider (LHC) at s√=7 TeV are presented. The luminosity is independently determined using several detectors and multiple algorithms, each having different acceptances, systematic uncertainties and sensitivity to background. The ratios of the luminosities obtained from these methods are monitored as a function of time and of μ, the average number of inelastic interactions per bunch crossing. Residual time- and μ-dependence between the methods is less than 2% for 0<μ<2.5. Absolute luminosity calibrations, performed using beam separation scans, have a common systematic uncertainty of ±11%, do…
Limits on the production of the standard model Higgs boson in pp collisions at root s=7 TeV with the ATLAS detector
2011
A search for the Standard Model Higgs boson at the Large Hadron Collider (LHC) running at a centre-of-mass energy of 7 TeV is reported, based on a total integrated luminosity of up to 40 pb−1 collected by the ATLAS detector in 2010. Several Higgs boson decay channels: H→γγ, H→ZZ(∗)→ℓℓℓℓ, H→ZZ→ℓℓνν, H→ZZ→ℓℓqq, H→WW(∗)→ℓνℓν and H→WW→ℓνqq (ℓ is e, μ) are combined in a mass range from 110 GeV to 600 GeV. The highest sensitivity is achieved in the mass range between 160 GeV and 170 GeV, where the expected 95% CL exclusion sensitivity is at Higgs boson production cross sections 2.3 times the Standard Model prediction. Upper limits on the cross section for its production are determined. Models wit…
Globorotalia truncatulinoides in the Mediterranean Basin during the Middle–Late Holocene: Bio-Chronological and Oceanographic Indicator
2022
The planktonic foraminiferal species Globorotalia truncatulinoides is widely used as a biostratigraphic proxy for the Quaternary in the Mediterranean region. High-resolution quantitative studies performed on sediment cores collected in the central and western Mediterranean Sea evidence a significant abundance of G. truncatulinoides during the Middle Holocene. The robust chronological frame allows us to date this bio-event to 4.8–4.4 ka Before Present (BP), very close to the base of the Meghalayan stage (4.2 ka BP). As a consequence, we propose that G. truncatulinoides can be considered a potential marker for the Middle–Late Holocene chronological subdivision. G. truncatulinoides is a deep-d…
Entry-Item-Quantity-ABC Analysis-Based Multitype Cigarette Fast Sorting System
2012
Published version of an article in the journal: Mathematical Problems in Engineering. Also available from the publisher at: http://dx.doi.org/10.1155/2012/847591 Open access Numerous items, small order, and frequent delivery are the characteristics of many distribution centers. Such characteristics generally increase the operating costs of the distribution center. To remedy this problem, this study employs the Entry-Item-Quantity (EIQ) method to identify the characteristic of the cigarette distribution center and further analyzes the importance degree of customers and the frequently ordered products by means of EQ/EN/IQ-B/IK statistic charts. Based on these analyses as well as the total rep…
Lavtemperatur brenselceller
2005
Dokumentet er en del av en eksamensoppgave i MEF4200 Energimaterialer ved UiO høsten 2004. Som del av eksamen i emnet MEF4200 Energimaterialer ved Universitetet i Oslo (UiO) høsten 2004 var oppgaven å skrive en populærvitenskapelig artikkel for avgangselever i videregående skole. Artikkelen presenteres her og omhandler lavtemperatur brenselceller. De brenselcelletypene som beskrives er alkaliske brenselceller, PEM-brenselceller og metanolbrenselceller, alle med en driftstemperatur på normalt under 100 °C, og deres bruksområder.