1,749 research outputs found
Development of an Event Builder software based on InfiniBand network for the LHCb experiment
No full textLHCb è uno dei quattro esperimenti principali, attualmente in funzione, presso il Large Hadron Collider (LHC) del CERN. I suoi obiettivi sono quelli di eseguire misure precise dei parametri della violazione di CP e di studiare decadimenti rari degli adroni contenenti i quark b e c. L’esperimento LHCb subirà un importante aggiornamento durante il secondo spegnimento di LHC (2018-2019), da realizzare con l'obiettivo di acquisire una quantità di dati un'ordine di grandezza superiore rispetto alle possibilità del presente rivelatore. L'aggiornamento del detector prevede la realizzazione di un trigger completamente software, che permette di acquisire dati alla frequenza di bunch crossing di 40 MHz senza limitazioni. A tale scopo è stata progettata una nuova scheda di acquisizione, ad alte prestazioni, basata sullo standard PCIe-3. Questa scheda permetterà la costruzione di un sistema di acquisizione efficiente, ed economicamente vantaggioso, utilizzando tecnologie di rete ad alte prestazioni.
Lo scopo di questa tesi è lo studio, la progettazione e l'implementazione del software impiegato per 'Event Builder del futuro rivelatore di LHCb. L'Event Builder sarà costituito da circa 500 nodi di calcolo, ciascuno dei quali eseguirà due funzioni logiche distinte: la Readout Unit (RU) e la Builder Unit (BU). Ciascuna RU, a partire dai dati provenienti dal detector, creerà un frammento di evento e lo spedirà ad una specifica BU in un modello "molti a uno”. Ciascuna BU ha la funzione di riaggregare i frammenti per creare gli eventi completi. Gli eventi completi sono spediti al sistema di trigger software per successive elaborazioni.
Attualmente la rete InfiniBand è la tecnologia di connessione più utilizzata nei supercalcolatori e fornisce le prestazioni migliori tra le tecnologie basate su standard aperti. Per queste ragioni ho scelto InfiniBand come tecnologia di rete per l'implementazione di questo Event Builder. Per prima cosa ho sviluppato il Communication Layer, un software per il trasferimento dati tra differenti nodi utilizzando i "verbi" di InfiniBand (una libreria che offre delle API che permettono di sfruttare le capacità RDMA della scheda).
Sopra al Communication Layer ho creato il Logic Layer dell'Event Builder, un software che simula la logica dell'event-building in maniera realistica. Questo software implementa un approccio "push" con regole di spedizione dedicate, in modo tale da minimizzare il rischio di congestione del traffico. Ho inoltre evitato l'utilizzo di un supervisore centrale, preferendo una strategia predefinita di scheduling.
L'Event Builder è stato testato in differenti centri di calcolo in modo tale da provare le prestazioni e la scalabilità del software. Infine, ho effettuato studi preliminari sulla possibilità di utilizzare architetture a basso consumo per sistemi di acquisizione ad alte prestazioni, utilizzando l'Event Builder come caso d'uso.The LHCb experiment is one of the four main experiments operating at the Large Hadron Collider at CERN. Its main goals are to make precise measurements of CP violation and to study rare decays of b and c-quark hadrons. The LHCb experiment will undergo a major upgrade during the second long shutdown (2018 - 2019), aiming at collecting an order of magnitude more data the possible with the present detector. The upgraded detector foresees a full software trigger, running at the LHC bunch crossing frequency of 40 MHz. A new high-throughput PCIe Generation 3 based read-out board has been designed on this purpose. The read-out board will allow an efficient and cost-effective implementation of the Data Acquisition System by means of high-speed PC networks.
The aim this thesis is to study, design and implement an efficient Event Builder software for the LHCb upgrade. The Event Builder will consist of about 500 nodes. Each server of the EB relies on two distinct logical components: the Readout Unit (RU) and the Builder Unit (BU). The RU packs the event fragments from the detector, and ship it to a receiving BU in a many-to-one pattern. Each BU gathers the event fragments to assemble them in the full events, which is sent out afterwards for filtering to a specific trigger farm unit. For these reasons I choose InfiniBand as network technology to build up the Event Builder implementation. I developed the EB Communication Layer software, to be used for data transfer among different nodes of the EB exploiting InfiniBand verbs, which is a library that offers an user space API to access the RDMA capabilities of the network device. The InfiniBand network standard is currently the most commonly used interconnection technology in supercomputers. It provides the best performances among the open-standard I/O technologies.
On top of the Communication Layer I created the Logic Layer of the Event Builder, a software that performs the event-building in a realistic way. This software implements a push approach with custom dispatching policies, minimizing the risk of traffic congestion. I also avoided the adoption of a central scheduler, preferring a predefined scheduling strategy. The Event Builder software was tested on different clusters in order to prove its performance and scalability. Finally, I performed preliminary studies on the possibility to use low power architectures for high-throughput data acquisition purposes, using the Event Builder software as use case
A general purpose suite for Grid resources exploitation
No full textWe present a general-purpose software framework, which allows different multi-disciplinary communities to take advantage of a distributed computational infrastructure. The ultimate goal is to provide organizations that need to exploit resources with CPU-intensive loose-parallel tasks with a software service capable to offer a user-friendly, standard and highly customizable access to the Grid. The software suite we developed has been designed specifically for organizations that cannot afford the adoption costs of more specialized and complex frameworks, developed in High Energy Physics (HEP) environment, but that still require an easy-to-use interface to the Grid. Our framework heavily relies on a bookkeeping database, storing both application-specific and infrastructure meta-data, which is tightly coupled with a web-based user-interface. The first makes available to the users information on the execution status of jobs and their specific meaning and parameters, and contributes in orchestrating the submission mechanism. The latter provides job submission management, bookkeeping database interactions, basic monitoring functionality and eLog system. Multi-site submissions based on user-defined requests and fine grain parametric submission interfaces are available. The structure of framework services follow a centralized design: job management service and bookkeeping database are hosted in a European Grid Infrastructure (EGI) site. Jobs executed into remote sites transfer their output to predefined target site repository and update the bookkeeping database. In addition, the framework requires a proper configuration of the remote Grid sites on which the jobs will run. Results from a large production of Monte Carlo simulated events submitted to 15 Grid sites are reported, and a comparison in terms of features, scopes, and targets, with a broad spectrum of general-purpose solutions in the same field of application is presented as well
The Trigger and Data Acquisition System for the 8 tower subsystem of the KM3NeT detector
No full textKM3NeT is a deep-sea research infrastructure being constructed in the Mediterranean Sea. It will host a large Cherenkov neutrino telescope that will collect photons emitted along the path of the charged particles produced in neutrino interactions in the vicinity of the detector. The philosophy of the DAQ system of the detector foresees that all data are sent to shore after a proper sampling of the photomultiplier signals. No off-shore hardware trigger is implemented and a software selection of the data is performed with an on-line Trigger and Data Acquisition System (TriDAS) to reduce the large throughput due to the environmental light background. A first version of the TriDAS has been developed to operate a prototype detection unit deployed in March 2013 in the abyssal site of Capo Passero (Sicily, Italy), about 3500 m deep. A revised and improved version has been developed to meet the requirements of the final detector, using new tools and modern design solutions. First installation and scalability tests have been performed at the Bologna Common Infrastructure and results comparable to what expected have been observed
The Trigger and Data Acquisition System for the KM3NeT-Italia towers
No full textKM3NeT-Italia is an INFN project supported with Italian PON fundings for building the core of the Italian node of the KM3NeT neutrino telescope. The detector, made of 700 10′′ Optical Modules (OMs) lodged along 8 vertical structures called towers, will be deployed starting from fall 2015 at the KM3NeT-Italy site, about 80 km off Capo Passero, Italy, 3500 m deep. The all data to shore approach is used to reduce the complexity of the submarine detector, demanding for an on-line trigger integrated in the data acquisition system running in the shore station, called TriDAS. Due to the large optical background in the sea from 40K decays and bioluminescence, the throughput from the underwater detector can range up to 30 Gbps. This puts strong constraints on the design and performances of the TriDAS and of the related network infrastructure. In this contribution the technology behind the implementation of the TriDAS infrastructure is reviewed, focusing on the relationship between the various components and their performances. The modular design of the TriDAS, which allows for its scalability up to a larger detector than the 8-tower configuration is also discussed
TUTELA DEL LAVORO E LIBERTA' D'IMPRESA NEI PROCESSI DI ESTERNALIZZAZIONE
No full textL’elaborato analizza le conseguenze lavoristiche della successione fra imprenditori, muovendo da una ricognizione delle varie tipologie di esternalizzazione con le relative esigenze e principali criticità.
L’indagine si concentra in primo luogo sul trasferimento d’azienda, esaminando la normativa e la giurisprudenza europee per passare poi alla disciplina di diritto interno, alle procedure sindacali e a uno specifico focus sul trasferimento delle aziende in crisi.
Successivamente l’autore si sofferma sull’appalto, prendendone in particolare considerazione gli indici di genuinità, i criteri di distinzione dalla somministrazione illecita di manodopera e la tutela delle maestranze in caso di avvicendamento fra imprese.
Da ultimo, la ricerca approfondisce le c.d. “clausole sociali”, sia di prima che di seconda generazione, valutandone la compatibilità con il diritto eurounitario e con la costituzione nonché riflettendo sui possibili rimedi in caso di loro violazione.The author analyzes the labour consequences of the succession between entrepreneurs, starting from a recognition of the various types of outsourcing with the related needs and main critical issues.
The survey focuses primarily on the transfer of businesses, examining European legislation and case-law and then moving on to internal legislation, trade union procedures and a specific focus on the transfer of companies in crisis.
The author then dwells on the contract, taking into account in particular the indications of authenticity, the criteria of distinction from the illicit administration of labour and the protection of workers in the event of turnover between companies.
Finally, the research deepens the "social clauses", both first and second generation, assessing their compatibility with European law and with the constitution and reflecting on possible remedies in case of their violation
Ultra Low Carbon Vehicles: New Parameters for Automotive Design
No full textAs the influence of vehicle emissions on our environment has become better understood, the UK government has recently placed urgent emphasis on the implementation of low carbon
technologies in the automotive industry through: the UK Low Carbon Industrial Strategy. The overall objective is to offer big incentives to consumers and support for the development of infrastructure and engineering solutions. This scheme however does not consider how the development of functional and experiential user value might drive consumer demand, contributing to the adoption of low carbon vehicles (LCVs) in the mass market.
With the emergence of the North East of England as the UK’s first specialised region for the development of ultra-low carbon vehicles (ULCVs), ONE North East, as a development agency for the region's economic and business development, and Northumbria University Ideas-lab have supported a project to facilitate innovation through the collaboration of technology, research and development (R&D) and business. The High Value Low Carbon (HVLC) project aims to envisage
new user value made possible by the integration of low carbon vehicle platforms with new process and network technologies. The HVLC consortium represents vehicle manufacturers and their suppliers as well as technology based companies and through an ongoing process of design concept generation the project offers a hub for innovation led enterprise.
Whilst new technological developments in areas such as power generation, nano materials, hydrogen fuel cells, printed electronics and networked communications will all impact on future automotive design, the mass adoption of low carbon technologies represents a paradigm shift for the motorist. This paper aims to describe how the mapping of new parameters will lead to new transport scenarios that will create the space for new collaborative research on user experiences supported by innovative technologies and related services
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Matteo Maria Boiardo (1441-1494)
No full textMatteo Maria Boiardo – contemporary of Sir Thomas Malory and forerunner of Shakespeare, Spenser, Milton, Cervantes, Tolkien, and C.S. Lewis – is best known as the author of the Orlando Innamorato [Orlando in Love], a poem in ottava rima organically merging Carolingian epic and Arthurian romance. He was also a lyric and pastoral poet, playwright, and translator of classical texts into the Italian vernacular. Matteo was active in Italy during the years of 1463 throughout 1494, the year of his death
Uno sguardo all'Est. Lavoro e diritti fondamentali in Russia e negli altri Paesi della Comunità di Stati indipendenti
No full textNel contributo l'autore, dopo aver esaminato i diritti fondamentali del lavoro presenti nelle Costituzioni dei Paesi della Comunità di Stati indipendenti, si sofferma sul diritto del lavoro russo. La trattazione, a carattere diacronico, abbraccia i rami principali del diritto del lavoro: il rapporto individuale, le relazioni collettive, il mercato del lavoro. L'autore rileva una sorprendente continuità nelle linee essenziali del diritto del lavoro russo, pur nel susseguirsi di sistemi socioeconomici completamente diversi. Egli conclude che il diritto del lavoro russo appartiene saldamente alla matrice europea della materia.The contribution of the author starts by examining fundamental labour rights recognised by the Constitutions of the Countries of the Community of Independent States. Then the author focuses upon Russian Labour Law, going through the history of the main branches of the discipline: the individual relationship, industrial relations, the labour market. The article finds a surprising continuity in the essential lines of Russian Labour Law, in spite of the completely different socio-economic systems that were experimented in Russia during the twentieth century. The author concludes that Russian Labour Law clearly belongs to the European matrix of the discipline
Large-scale DAQ tests for the LHCb upgrade
No full textThe Data Acquisition (DAQ) of the LHCb experiment[1] will be upgraded in 2020 to a high-bandwidth trigger-less readout system. In the new DAQ event fragments will be forwarded to the to the Event Builder (EB) computing farm at 40 MHz. Therefore the front-end boards will be connected directly to the EB farm through optical links and PCI Express based interface cards. The EB is requested to provide a total network capacity of 32Tb/s, exploiting about 500 nodes. In order to get the required network capacity we are testing various technology and network protocols on large scale clusters. We developed on this purpose an Event Builder implementation designed for an InfiniBand interconnect infrastructure. We present the results of the measurements performed to evaluate throughput and scalability measurements on HPC scale facilities
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