317 research outputs found
Public and private food procurement and short food value chains in urban areas: a case study analysis
No full textThis chapter explores the PPP-URB (Public and Private Food Procurement and Short Food Value Chains in Urban Areas) project within the Onfoods PNRR research. It details how the project has been organized through a system design approach by the coordinator (Politecnico di Milano - Design Department) to embrace the diversity of disciplines and various points of view and approaches to the topic. It outlines the overall organization and dives deep into the first deliverable on the analysis of case studies through the different expertise lenses of the partners. The project focuses on the food ecosystems within small territorial units, specifically tailored to university campuses, to understand their role in local food systems. The first deliverable of the PPP-URB is related to the analysis of case studies useful for approaching the second deliverable, which concerns strategic approaches to the topic, and the third, related to in-field experimentation. The author describes how the partnership has been organized and how the case studies analysis has been approached, providing key insights for the following chapters that dive deep into the case studies through the expertise lenses of the partners
Events and the city - When Arnold meets NoLo
No full textthe author presents the result of "Arnold" second phase, "from prototyping to mise-en-scene" and collateral initiatives, with a strong accent on the role of the temporary event (and its construction) as a mean of creating scenarios for long term and creative use of spaces to improve the quality of the neighbourhood. The input artists and designers involved gave to reach the action prototyping was the shift from being object maker to maker of experiences (Spayde, 2012). The output of the second phase were read through the legacy left to the neighbourhood, the impact of the actions and the sustainability of the event making. "Arnold" created a system of actors related to art and design in the area creating an event format to be possibly used even in future as an annual appointment for the city. It involves a substantial number of stakeholders including professionals, artist, citizens and caught the attention by several media thanks to the sinergy with collateral event such as "ZuArt -Looper fest" and "GiraNolo". Further it was a sustainable event from the environmental and economic point of view and let the visitors have a social interaction aided at improving their level of satisfaction (Nordvall et al., 2014)
Searches for heavy resonances decaying to top quarks with the ATLAS detector
No full textSeveral models of physics beyond the Standard Model contain preferential couplings to top quarks. A search for new phenomena in t̄t final states with additional heavy-flavour jets as well as the new physics of heavy gauge bosons hadronically-decaying resonances. The searches have been carried out using proton-proton collision data collected with the ATLAS detector at LHC at a centre-of-mass energy of 13 TeV. Data are analysed in the lepton-plus-jets final state and as large-radius jets, characteristic of signal events
ATLAS Distributed Data Analysis: challenges and performance
No full textIn the LHC operations era the key goal is to analyse the results of the collisions of high-energy particles as a way of probing the fundamental forces of nature. The ATLAS experiment at the LHC at CERN is recording and simulating several 10's of PetaBytes of data per year. The ATLAS Computing Model was designed around the concepts of Grid Computing. Large data volumes from the detectors and simulations require a large number of CPUs and storage space for data processing. To cope with this challenge a global network known as the Worldwide LHC Computing Grid (WLCG) was built. This is the most sophisticated data taking and analysis system ever built. ATLAS accumulated more than 140 PB of data between 2009 and 2014. To analyse these data ATLAS developed, deployed and now operates a mature and stable distributed analysis (DA) service on the WLCG. The service is actively used: more than half a million user jobs run daily on DA resources, submitted by more than 1500 ATLAS physicists. A significant reliability of the DA system during the first run and the following shutdown period has been reached due to the continuous automatic validation of the grid sites against a set of standard tests, and a dedicated team of expert shifters who provide user support and communicate user problems to the sites in a more efficient way. In this report we review the state of the DA system, emphasis will be put on the DA infrastructure changes to cope with the second LHC run challenges (starting in 2015) to improve the analysis workflows, including a new analysis model. A special care will be devoted to discuss the ATLAS Distributed Analysis support facility (DAST)
Achievements of the ATLAS Distributed Analysis during the first run period
No full textSummary : In the LHC operations era analyzing the large data by the distributed physicists becomes a challenging task. The Computing Model of the ATLAS experiment at the LHC at CERN was designed around the concepts of grid computing. Large data volumes from the detectors and simulations require a large number of CPUs and storage space for data processing. To cope with these challenges a global network known as the Worlwide LHC Computing Grid (WLCG) was built. This is the most sophisticated data taking and analysis system ever built. Since the start of data-taking, the ATLAS Distributed Analysis (ADA) service has been running stably with the huge amount of data. The reliability of the ADA service is high but steadily improving; grid sites are continually validated against a set of standard tests, and a dedicated team of expert shifters provides user support and communicates user problems to the sites. The ATLAS Grid Computing Model is reviewed in this talk. Emphasis is given to ADA system. Description : The central goal here is to analyze the results of the collisions of high energy particles as a way of probing the fundamental forces of nature. The challenge in a LHC data analysis is the need to explore large data volumes from the detectors and simulation, which require a large number of CPUs for processing. In addition to the complex experiment software structure and a high connectivity to the data that needs to be provided by the large-scale physics analysis activities. Analysis jobs are routed to sites based on the availability of relevant data and processing resources. The data distribution is optimized to fit the resource distribution, and it is dynamically changed to meet rapidly the evolving requirements for analysis use cases. Distributed analysis tools used to analyze the data are reliable and fast to work with. Both the user support techniques and the direct feedback of users are the goal of improving the success rate and user experience when utilizing the distributed computing environment. The service is actively used: more than 1600 users have submitted jobs in the year 2012 and more than 2 million analysis jobs per week. PanDA is the ATLAS workload management system for processing user analysis, group analysis and production jobs. The reliability of the ADA service is high but steadily improving; grid sites are continually validated against a set of standard tests, and a dedicated team of expert shifters provides user support and communicates user problems to the sites. The ATLAS Grid Computing Model is reviewed in this talk as to how the ATLAS data is stored, distributed and processed. An emphasis is given on the distributed data analysis services, summarize this year of distributed analysis activity, and present the perspectives for future improvements to the system. Impact : The WLCG approach has the benefit of distributing responsibility in such a way that CERN’s role is to generate the raw data along with the additional calibration needed to interpret it while the broad international community accesses and analyzes this data through its own hierarchical network. The main point is that the data analysis, storage and deployment are driven by the requirements of the experimenters and theoretical analysts. Big achievements make the collection, handling and basic analysis of large data feasible. The LHC data intensive science activities have proved that the data volumes are large but they are not unmanageable. This is a very valuable experience for the scientific community that faces the challenge of storing, analysing and accessing large data sets, as well as the need to archive data in a robust and enduring way
ATLAS Distributed Data Analysis: performance and challenges
No full textIn the LHC operations era the key goal is to analyse the results of the collisions of high-energy particles as a way of probing the fundamental forces of nature. The ATLAS experiment at the LHC at CERN is recording and simulating several 10's of PetaBytes of data per year. The ATLAS Computing Model was designed around the concepts of Grid Computing. Large data volumes from the detectors and simulations require a large number of CPUs and storage space for data processing. To cope with this challenge a global network known as the Worldwide LHC Computing Grid (WLCG) was built. This is the most sophisticated data taking and analysis system ever built. ATLAS accumulated more than 140 PB of data between 2009 and 2014. To analyse these data ATLAS developed, deployed and now operates a mature and stable distributed analysis (DA) service on the WLCG. The service is actively used: more than half a million user jobs run daily on DA resources, submitted by more than 1500 ATLAS physicists. A significant reliability of the DA system during the first run and the following shutdown period has been reached due to the continuous automatic validation of the grid sites against a set of standard tests, and a dedicated team of expert shifters who provide user support and communicate user problems to the sites in a more efficient way. In this report we review the state of the DA system, emphasis will be put on the DA infrastructure changes to cope with the second LHC run challenges (starting in 2015) to improve the analysis workflows, including a new analysis model. A special care will be devoted to discuss the ATLAS Distributed Analysis support facility (DAST)
Searches for new physics with top- and bottom-quark signatures using the ATLAS detector
No full textHigh-mass resonances or new particles decaying into top- and/or bottom-quark + X are predicted in many new physics scenarios including extended gauge models, extra dimensions, 2HDM, etc. The vector-like quarks (VLQs), preferentially coupled to the third generation SM quarks, are also predicted e.g, in composite Higgs models as a “natural” way to stabilise the Higgs boson mass. This talk highlights recent ATLAS searches with the third generation quarks using LHC Run 1 data. First LHC Run-2 results will be included if available
Study of the ATLAS Tile-Cal performance: Precise determination of the top mass
No full textA new very promising method for the top mass reconstruction in ATLAS is presented. The method uses a special sub-sample of the single lepton plus jet events where the top has high pt (pt>200 Gev), available with acceptable statistics at LHC due to the high ttbar production rate. The top mass is reconstructed as the invariant mass of all the calorimeter towers in a cone around the top quark direction. From studies made with both the fast and full detector simulation programs, it is shown that an accuracy of 1-1.5 in the reconstructed top quark mass can be achieved, using only one year's data at low luminosity of LHC (10 invfb). A detailed study of the systematic errors involved with the measurement is discussed as well
Four top probes of new physics
No full textIn the Standard Model (SM) of particle physics, four-top-quark production is an extremely rare process with a cross section of approximately 12 fb. In extensions of the SM with top-philic new states, the four-top production rate can be enhanced considerably. In this contribution results will be presented of searches by the ATLAS and CMS experiments that have yielded the first evidence for the SM process, as well as stringent bounds on more exotic production mechanism of the same final state. The talk will address a review of the latest results of the SM ̅̅ searches at ATLAS and CMS. The results of the BSM ̅̅ searches at ATLAS will be discussed as well
Performance Indices for the Evaluation of Microgrippers Precision in Grasping and Releasing Phases
No full textIn manipulating and assembly tasks, the gripper plays a fundamental role. Tasks at the microscale are particularly challenging due to the possible effect of unwanted stiction. Many different grasping tools (generally called microgrippers) have been developed and are described in literature. The differences rely on size, shape, exchanged forces with the manipulated parts and working principle depending on the application field. Despite the large number of research and industrial cases, each author has developed different and not comparable procedures and indices to assess the device grasping and releasing performance. Therefore, the paper proposes a formalization of methods and indices for the evaluation of the performance of a generic contact microgripper in terms of precision in grasping and releasing and successful rate. This review could be helpful to support the design or the choice of the most suitable gripper according to the properties of the components to be manipulated, the task requirements and the system constraints (i.e., according to the application requirements). The validity of the proposed methodologies and indices is confirmed by theory and experimental data analysis
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