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Search Results: 1 - 10 of 3476 matches for " Federico Calzolari "
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CP Violation and K0 decays revelation: study and simulation of neutral Trigger in NA48 experiment -- Violazione di CP e rivelazione dei decadimenti del K0: studio e simulazione del Trigger neutro nell'esperimento NA48
Federico Calzolari
Physics , 2007,
Abstract: At the INFN laboratory in Pisa I have prepared my dissertation, which essentially concerned Montecarlo simulation of subnuclear particles decays and investigation of low-noise electronic devices for analyzing high-frequency signals. The team-work was part of NA48/EPSI experiment jointly carried out with European Organization for Nuclear Research CERN, Geneva. ----- Nell'ambito dell'esperimento NA48 in corso al CERN Super Proton Syncrothon (SPS) finalizzato a misurare la violazione diretta di CP in sistemi di particelle K0 attraverso il doppio rapporto R = [N(K_L->Pi0Pi0)]/[N(K_S->Pi0Pi0)] / [N(K_L->Pi+Pi-)]/[N(K_S->Pi+Pi-)] = 1 - 6 Re(e1/e) con una precisione di Re(e1/e) superiore a 2 * 10^-4, il lavoro di tesi si propone di effettuare una simulazione per la rivelazione dei decadimenti neutri dei K0 ed una successiva analisi dei dati raffrontando l'evento fisico generato con metodo Montecarlo e quello ricostruito. Per la misura di e1/e occorre isolare tra i vari modi di decadimento dei K quelli K_S->Pi0Pi0, K_S->Pi+Pi-, e quelli K_L->Pi0Pi0, K_L->Pi+Pi-.
High availability using virtualization
Federico Calzolari
Computer Science , 2009,
Abstract: High availability has always been one of the main problems for a data center. Till now high availability was achieved by host per host redundancy, a highly expensive method in terms of hardware and human costs. A new approach to the problem can be offered by virtualization. Using virtualization, it is possible to achieve a redundancy system for all the services running on a data center. This new approach to high availability allows to share the running virtual machines over the servers up and running, by exploiting the features of the virtualization layer: start, stop and move virtual machines between physical hosts. The system (3RC) is based on a finite state machine with hysteresis, providing the possibility to restart each virtual machine over any physical host, or reinstall it from scratch. A complete infrastructure has been developed to install operating system and middleware in a few minutes. To virtualize the main servers of a data center, a new procedure has been developed to migrate physical to virtual hosts. The whole Grid data center SNS-PISA is running at the moment in virtual environment under the high availability system. As extension of the 3RC architecture, several storage solutions have been tested to store and centralize all the virtual disks, from NAS to SAN, to grant data safety and access from everywhere. Exploiting virtualization and ability to automatically reinstall a host, we provide a sort of host on-demand, where the action on a virtual machine is performed only when a disaster occurs.
Proxy dynamic delegation in grid gateway
Federico Calzolari,Daniele Licari
Computer Science , 2012,
Abstract: Nowadays one of the main obstacles the research comes up against is the difficulty in accessing the required computational resources. Grid is able to offer the user a wide set of resources, even if they are often too hard to exploit for non expert end user. Use simplification has today become a common practice in the access and utilization of Cloud, Grid, and data center resources. With the launch of L-GRID gateway, we introduced a new way to deal with Grid portals. L-GRID is an extremely light portal developed in order to access the EGI Grid infrastructure via Web, allowing users to submit their jobs from whatever Web browser in a few minutes, without any knowledge about the underlying Grid infrastructure.
A new job migration algorithm to improve data center efficiency
Federico Calzolari,Silvia Volpe
Computer Science , 2012,
Abstract: The under exploitation of the available resources risks to be one of the main problems for a computing center. The growing demand of computational power necessarily entails more complex approaches in the management of the computing resources, with particular attention to the batch queue system scheduler. In a heterogeneous batch queue system, available for both serial single core processes and parallel multi core jobs, it may happen that one or more computational nodes composing the cluster are not fully occupied, running a number of jobs lower than their actual capability. A typical case is represented by more single core jobs running each one over a different multi core server, while more parallel jobs - requiring all the available cores of a host - are queued. A job rearrangement executed at runtime is able to free extra resources, in order to host new processes. We present an efficient method to improve the computing resources exploitation.
The Anatomy of a Grid portal
Daniele Licari,Federico Calzolari
Computer Science , 2012, DOI: 10.1088/1742-6596/331/7/072043
Abstract: In this paper we introduce a new way to deal with Grid portals referring to our implementation. L-GRID is a light portal to access the EGEE/EGI Grid infrastructure via Web, allowing users to submit their jobs from a common Web browser in a few minutes, without any knowledge about the Grid infrastructure. It provides the control over the complete lifecycle of a Grid Job, from its submission and status monitoring, to the output retrieval. The system, implemented as client-server architecture, is based on the Globus Grid middleware. The client side application is based on a java applet; the server relies on a Globus User Interface. There is no need of user registration on the server side, and the user needs only his own X.509 personal certificate. The system is user-friendly, secure (it uses SSL protocol, mechanism for dynamic delegation and identity creation in public key infrastructures), highly customizable, open source, and easy to install. The X.509 personal certificate does not get out from the local machine. It allows to reduce the time spent for the job submission, granting at the same time a higher efficiency and a better security level in proxy delegation and management.
Operations structure for the management, control and support of the INFN-GRID/Grid.It production infrastructure
Maria Cristina Vistoli,Luciano Gaido,Federico Calzolari
Physics , 2007,
Abstract: Moving from a National Grid Testbed to a Production quality Grid service for the HEP applications requires an effective operations structure and organization, proper user and operations support, flexible and efficient management and monitoring tools. Moreover the middleware releases should be easily deployable using flexible configuration tools, suitable for various and different local computing farms. The organizational model, the available tools and the agreed procedures for operating the national/regional grid infrastructures that are part of the world-wide EGEE grid as well as the interconnection of the regional operations structures with the global management, control and support structure play a key role for the success of a real production grid. In this paper we describe the operations structure that we are currently using at the Italian Grid Operation and Support Center. The activities described cover monitoring, management and support for the INFN-GRID/Grid.It production grid (spread over more than 30 sites) and its interconnection with the EGEE/LCG structure as well as the roadmap to improve the global support quality, stability and reliability of the Grid service.
Unifying Lexicons in view of a Phonological and Morphological Lexical DB
Federico Calzolari,Michele Mammini,Monica Monachini
Computer Science , 2006,
Abstract: The present work falls in the line of activities promoted by the European Languguage Resource Association (ELRA) Production Committee (PCom) and raises issues in methods, procedures and tools for the reusability, creation, and management of Language Resources. A two-fold purpose lies behind this experiment. The first aim is to investigate the feasibility, define methods and procedures for combining two Italian lexical resources that have incompatible formats and complementary information into a Unified Lexicon (UL). The adopted strategy and the procedures appointed are described together with the driving criterion of the merging task, where a balance between human and computational efforts is pursued. The coverage of the UL has been maximized, by making use of simple and fast matching procedures. The second aim is to exploit this newly obtained resource for implementing the phonological and morphological layers of the CLIPS lexical database. Implementing these new layers and linking them with the already exisitng syntactic and semantic layers is not a trivial task. The constraints imposed by the model, the impact at the architectural level and the solution adopted in order to make the whole database `speak' efficiently are presented. Advantages vs. disadvantages are discussed.
Next Generation Language Resources using GRID
Federico Calzolari,Eva Sassolini,Manuela Sassi,Sebastiana Cucurullo,Eugenio Picchi,Francesca Bertagna,Alessandro Enea,Monica Monachini,Claudia Soria,Nicoletta Calzolari
Computer Science , 2006,
Abstract: This paper presents a case study concerning the challenges and requirements posed by next generation language resources, realized as an overall model of open, distributed and collaborative language infrastructure. If a sort of "new paradigm" is required, we think that the emerging and still evolving technology connected to Grid computing is a very interesting and suitable one for a concrete realization of this vision. Given the current limitations of Grid computing, it is very important to test the new environment on basic language analysis tools, in order to get the feeling of what are the potentialities and possible limitations connected to its use in NLP. For this reason, we have done some experiments on a module of Linguistic Miner, i.e. the extraction of linguistic patterns from restricted domain corpora.
High availability using virtualization - 3RC
Federico Calzolari,Silvia Arezzini,Alberto Ciampa,Enrico Mazzoni,Andrea Domenici,Gigliola Vaglini
Computer Science , 2012, DOI: 10.1088/1742-6596/219/5/052017
Abstract: High availability has always been one of the main problems for a data center. Till now high availability was achieved by host per host redundancy, a highly expensive method in terms of hardware and human costs. A new approach to the problem can be offered by virtualization. Using virtualization, it is possible to achieve a redundancy system for all the services running on a data center. This new approach to high availability allows the running virtual machines to be distributed over a small number of servers, by exploiting the features of the virtualization layer: start, stop and move virtual machines between physical hosts. The 3RC system is based on a finite state machine, providing the possibility to restart each virtual machine over any physical host, or reinstall it from scratch. A complete infrastructure has been developed to install operating system and middleware in a few minutes. To virtualize the main servers of a data center, a new procedure has been developed to migrate physical to virtual hosts. The whole Grid data center SNS-PISA is running at the moment in virtual environment under the high availability system.
Enlargement of filtration and predictable representation property for semi-martingales
Antonella Calzolari,Barbara Torti
Mathematics , 2013,
Abstract: We present two examples of loss of the predictable representation property for semi-martingales by enlargement of the reference filtration. First of all we show that the predictable representation property for a square-integrable semi-martingale X does not transfer from the reference filtration F to a larger filtration G when the information starts growing up to a positive time. Then we study the case when F coincides with the natural filtration of X and G is obtained by adding the natural filtration of a second square-integrable semi-martingale, Y. We establish conditions under which the triplet (X,Y,[X,Y]) enjoys the predictable representation property with respect to G.
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