1,721,208 research outputs found
The inflammatory reflex reloaded
No full textIn their recent paper in Brain, Behavior, and Immunity, Katayama and colleagues outlined the neural pathway of a basic neural reflex responsible for the endogenous inhibition of inflammation (Katayama et al., 2022)
Workshop Tematico: LFR-GEN IV Stato attuale della tecnologia e prospettive di sviluppo
No full textPresso il CR ENEA “E. Clementel” di Bologna si terrà, dal 15 al 16 Gennaio 2014, un Workshop tematico dal titolo “LFR-GEN IV STATO ATTUALE DELLA TECNOLOGIA E PROSPETTIVE DI SVILUPPO”, organizzato da ENEA in collaborazione con le principali università italiane che svolgono attività di ricerca in campo nucleare. Il Workshop, promosso nell’ambito delle attività inerenti la Linea Progettuale 2 “Collaborazione internazionale per il nucleare di IV generazione” dell’ AdP MSE-ENEA, assume il duplice obiettivo di condividere lo stato dell’arte dei sistemi LFR tra gli stakeholder italiani definendo al contempo, in maniera condivisa e sinergica con il contesto Europeo, le linee di intervento future in ambito LFR
Numerical analysis of the thermal-hydraulic behaviour of the ICE test section by the coupling of a system code and a CFD code
Full text linkIn this report the thermal fluid-dynamics results of the DHR (Decay Heat Removal) pre-test analysis of the test foreseen at ENEA by the ICE (Integral Circulation Eutectic) test section of CIRCE (CIRCulation Eutectic) facility are presented. The aim of this work is the study of the PLOHS (Protective Loss Of Heat Source) + LOF (Loss Of Flow) accident that in a LFR (Lead Fast Reactor) consists in the loss of all primary pumps and secondary circuits, with consequent reactor scram and decay heat removed in natural circulation by emergency systems (DHR-HXs).
In order to better represent the boundary conditions a one way coupled model between the RELAP5 system code and the CFD Fluent code was developed. In particular, the boundary conditions implemented in the Fluent code as the HX (Heat eXchanger) removed power and the LBE (Lead-Bismuth Eutectic) flow rate at the entrance of the HS (Heater System) were set-up by previous RELAP5 stand alone simulations. The CFD (Computational Fluid Dynamic) analysis was performed adopting an axial-symmetric domain and assuming adiabatic the external walls. The natural circulation in the HLM (Heavy Liquid Metal) pool and the cooling capability of air circulating in the secondary side of the DHR were also investigated in transient conditions. Twenty hours of transient analysis were performed and at the end of that time the system had not yet reached complete steady state conditions. At t = 20 h, the temperature results show a stratified temperature field in the pool region, reaching a distribution in which the upper region is characterized by a temperature of about 316°C and a lower region in which the LB) reaches an approximately uniform value of about 283°C. The LBE mass flow rate in the DHR annular region reaches a value of about 7.5 kg/s (i.e. about 94% of the total LBE mass flow rate entering at the inlet section); under these conditions the DHR system is able to remove about 39 kW of heat power from the vessel, which represents 5% of the nominal power generated before the accident
Validation of the coupled calculation between RELAP5 STH code and Ansys FLUENT CFD code
Full text linkThis report, carried out at the DICI (Dipartimento di Ingegneria Civile e Industriale) of the University of, illustrates the activities performed in the framework of the AdP2013 and dealing with the application of an in-house developed coupling methodology between a modified version of RELAP5/Mod3.3 and Fluent commercial CFD code, to the NACIE (Natural Circulation Experiment) LBE experimental loop (built and located at the ENEA Brasimone research centre). In particular, the first part of this work deals with the application of the developed two way explicit coupling tool to a simulation representative of a natural circulation test with a heating power of about 21.5 kW. The second part of the document deals with the development of an implicit coupling scheme in order to increase the numerical stability of the coupled simulations and its application to simulate an experimental test representative of an isothermal gas enhanced circulation test. Obtained results show a good agreement with the experimental data; moreover, the robustness of the developed implicit scheme allows the use of larger time steps reducing significantly the computational time. Finally, in order to further reduce the computational efforts, the User Defined Function realized for the Fluent code to receive b.c. data from RELAP5 and to send b.c data to RELAP5 for each CFD time step was parallelized allowing to run the CFD code using multiple processor and thus reducing the computational time especially for those simulations involving a 3D-CFD geometrical domain
Holographic renormalization and Ward identities with the Hamilton-Jacobi method
No full textpreprint: ArXiV:hep-th/020506
L’analisi del rischio locatario nel mercato immobiliare italiano
Full text linkLa difficoltà di riallocazione degli immobili che potrebbero essere lasciati vacanti dagli affittuari a causa dell’attuale crisi ha riportato alla luce un rischio spesso sottovalutato in passato dagli operatori: il rischio locatario. Scopo del presente lavoro è l’analisi del rischio tenant degli investimenti immobiliari nel mercato domestico, concentrandosi in modo particolare su tre aspetti specifici: dapprima viene presentata una fotografia del mercato italiano, con l’obiettivo di verificare se la durata “reale” dei contratti sia inferiore a quella pattuita inizialmente per via dell’esercizio delle opzioni di recesso anticipato da parte degli locatari. La seconda parte della ricerca è invece incentrata sulla verifica delle modalità con cui gli investitori professionali gestiscono questa componente aleatoria, al fine di verificare se le diverse asset allocation considerano anche tale fattore di rischio. L’ultima parte dell’analisi, infine, è dedicata all’impostazione di un modello statistico che mira ad individuare eventuali situazioni di tensione, ossia casi in cui le possibilità di abbandono dell’immobile da parte dei locatari sono particolarmente elevate.Difficulties in relocating buildings that occupants could leave vacant due to the current crisis have induced landlords to consider a risk that in the past was in most cases underestimated: the tenant risk. The aim of this study is to analyze the tenant risk in the Italian real estate market, focusing especially on three different aspects: firstly, the study presents an overview of the Italian real estate market, in order to verify whether the effective contract lengths are lower than those ones agreed at the stipulation dates, due to the exercise of break options by tenants. Then the study analyzes in details if and how professional investors manage this kind of risk, in order to determine whether different asset allocations consider this risky factor. Finally, the last part of the study aims to build a statistical model which helps landlords in identifying possible critical situations, i.e. cases where the probability of the break option exercise by tenants is particularly high
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
The impact of corporate culture, efficiency and geographic distance on M&A results: the European case
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