Search results for "Atlas"
showing 10 items of 652 documents
Challenges of the ATLAS Monte Carlo production during run 1 and beyond
2013
In this paper we will review the ATLAS Monte Carlo production setup including the different production steps involved in full and fast detector simulation. A report on the Monte Carlo production campaigns during run 1 and long shutdown 1 will be presented, including details on various performance aspects. Important improvements in the work flow and software will be highlighted. Besides standard Monte Carlo production for data analyses at 7 and 8 TeV, the production accommodates for various specialised activities. These ranges from extended Monte Carlo validation, Geant4 validation, pileup simulation using zero bias data and production for various upgrade studies. The challenges of these act…
Measuring lepton flavor violation at LHC with a long-lived slepton in the coannihilation region
2008
When the mass difference between the lightest slepton, the NLSP, and the lightest neutralino, the LSP, is smaller than the tau mass, the lifetime of the lightest slepton increases in many orders of magnitude with respect to typical lifetimes of other supersymmetric particles. These small mass differences are possible in the MSSM and, for instance, they correspond to the coannihilation region of the CMSSM for $M_{1/2} \gsim 700$ GeV. In a general gravity-mediated MSSM, where the lightest supersymmetric particle is the neutralino, the lifetime of the lightest slepton is inversely proportional to the square of the intergenerational mixing in the slepton mass matrices. Such a long-lived slepton…
A framework for vertex reconstruction in the ATLAS experiment at LHC
2010
In anticipation of the first LHC data to come, a considerable effort has been devoted to ensure the efficient reconstruction of vertices in the ATLAS detector. This includes the reconstruction of photon conversions, long lived particles, secondary vertices in jets as well as finding and fitting of primary vertices. The implementation of the corresponding algorithms requires a modular design based on the use of abstract interfaces and a common Event Data Model. An enhanced software framework addressing various physics applications of vertex reconstruction has been developed in the ATLAS experiment. Presented in this paper are the general principles of this framework. A particular emphasis is…
Atlas selection strategy using least angle regression in multi-atlas segmentation propagation
2011
International audience; In multi-atlas based segmentation propagation, segmentations from multiple atlases are propagated to the target image and combined to produce the segmentation result. Local weighted voting (LWV) method is a classifier fusion method which combines the propagated atlases weighted by local image similarity. We demonstrate that the segmentation accuracy using LWV improves as the number of atlases increases. Under this context, we show that introducing diversity in addition to image similarity by using least-angle regression (LAR) criteria is a more efficient way to rank and select atlases. The accuracy of multi-atlas segmentation converges faster when the atlases are sel…
SINCONAPP: A Computerized learning tool for CBCT normal anatomy and variants of the nose and paranasal sinuses
2014
1. Purpose To supply an useful learning tool aimed to interactively display on mobile devices normal anatomy and variants of the nose and paranasal sinuses as seen on CBCT images. 2. Methods and Materials Images Images of the nose and paranasal sinuses were derived by a study series acquired by a CBCT device. CBCT studies of the paranasal sinuses were acquired in patients referred for nasal obstruction or sinusitis with the following parameters: 90 kVp, 12.5 mA, 20 s rotation time, FOV 13 x 14.5 cm, 0.25 x 0.25 x 0.25 mm voxel size. Software The application has been developed for iOS based mobile devices through the platform XCode provided by Apple®, and it is developed using the Objective-…
Innovations in the Art of Microneurosurgery for Reaching Deep-Seated Cerebral Lesions.
2019
Deep-seated cerebral lesions have fascinated and frustrated countless surgical innovators since the dawn of the microneurosurgical era. To determine the optimal approach, the microneurosurgeon must take into account the characteristics and location of the pathological lesion as well as the operator's range of technical expertise. Increasingly, microneurosurgeons must select between multiple operative corridors that can provide access to the surgical target. Innovative trajectories have emerged for many indications that provide more flexible operative angles and superior exposure but result in longer working distances and more technically demanding maneuvers. In this article, we highlight 4 …
Jaunākā krievu daiļliteratūra krievu valodas kā svešvalodas stundās 12. klasē
2017
Diplomdarba tēma «JAUNĀKĀ KRIEVU DAIĻLITERATŪRA KRIEVU VALODAS KĀ SVEŠVALODAS STUNDĀS 12.KLASĒ.» -2017.g. Darba autore : LU Pedagoģijas,psiholoģijas un mākslas fakultātes studente Olga Karpova Darba vadītāja: Dr.paed.,doc.Jeļena Marčenko Diplomdarba apjoms: 52 lpp., kurās ir divas nodaļas, literatūras saraksts un pielikums. Diplomdarba tapšanas procesā tika izmantoti 22 avoti. Diplomdarbs satur materiālus, kas domāti izmantošanai krievu valodas kā svešvalodas stundās. Par pamata avotiem izmantoti jaunākās krievu literatūras teksti, kuru autori ir literāra konkursa "Debjut" laureāti un dalībnieki un tieši šie darbi kļuva par diplomdarba izpētes priekšmetu. Veidojot šos materiālus tika izvēlē…
Personāla atlases process Kuldīgas novada pašvaldībā
2019
Šī darba būtība ir parādīt un uzsvērt personāla atlases procesa nozīmīgumu valsts pārvaldes iestādē – Kuldīgas novada pašvaldībā (turpmāk – KNP). Personāla atlases process ir ikvienas iestādes pamatu pamats, bez kura nav iespējams izveidot iestādes prasībām un vajadzībām atbilstošu darbinieku komandu, kas veicinātu iestādes izaugsmi un uzstādīto mērķu sasniegšanu. Darba pirmajā daļā tiek raksturota personāla atlases būtība. Otrajā daļa tiek teorētiski analizēts personāla atlases process un tā posmi. Trešajā daļā tiek raksturota Kuldīgas novada pašvaldība, tās struktūra, funkcijas, mērķi un misija. Ceturtajā daļā tiek pētīti un analizēti divi dažādu amatu personāla atlases procesi KNP. Piekt…
Le anfore fenicio-puniche prodotte nel Mediterraneo occidentale: caratteristiche petrografiche degli impasti siciliani e spagnoli.
2009
The aim of this paper is to provide well-stated petrographic reference groups for the recognition of several Sicilian and Spanish Phoenician-Punic production centres in order to facilitate an instrument of further objective support for amphorae provenance. This instrument is based on the crosschecking between data provided by typological studies and the thinsection analysis of amphorae fabrics. It is worth noting that this is only a first step within the framework of a larger research project focused in the creation of an Atlas of Phoenician and Punic Amphorae in the Western Mediterranean including both archaeological and petrographic data. In this context a systematical work on the known p…
Performance of ATLAS tracking detector
2012
The track and vertex reconstruction algorithms of the ATLAS Inner Detector have demonstrated excellent performance in the early data from the LHC. However, the rapidly increas- ing number of interactions per bunch crossing introduces new challenges both in computational aspects and physics performance. The combination of both silicon and gas based detectors provides high precision impact parameter and momentum measurement of charged particles, with high efficiency and small fake rate. Vertex reconstruction is used to identify with high efficiency the hard scattering process and to measure the amount of pile-up interactions, both aspects are cru- cial for many physics analyses. The performan…