2,043 research outputs found
Development of innovative materials for building envelopes in dynamic behavior for energy saving and environmental sustainability
No full textIl risparmio energetico, lo sfruttamento delle energie rinnovabili, il rispetto dell'ambiente, e il comfort abitativo, rappresentano gli obiettivi della ricerca condotta, afferente il tema della Protezione Civile ed Ambientale, in 'ambito edilizio. Nello specifico sono stati sviluppati vetri innovativi capaci di conciliare aspetti contrastanti quali: garantire l'introspezione di luce naturale e nello stesso tempo gestire gli apporti termici esterni. I prototipi studiati riescono ad adattarsi agli stimoli esterni, grazie ad elementi fotocromatici organici che, sotto la radiazione solare, si oscurano gradualmente aumentando l'energia riflessa e garantendo il contenimento delle temperature interne.
Al calare della radiazione solare, tornano trasparenti lasciando filtrare la luce solare. La ratio dei vetri è la schermatura dell'energia termica grazie all'assemblaggio di vetri Low-E, riflettenti le radiazioni dell'infrarosso, con elementi fotocromatici in grado di riflettere, attivandosi, la banda ultravioletta e gran parte della radiazione visibile. Nelle campagne sperimentali, è stato possibile apprezzare le prestazioni dei vetri sperimentali, confrontandole con quelle di un modulo bassoemissivo campione (uno dei prodotti più performanti e diffusi sul mercato). I vantaggi dei vetri sperimentali sono stati quantificati, secondo le procedure tecniche dalle Norme UNI EN 410/2000 e UNI EN 673/2011, attraverso la valutazione dei parametri caratterizzanti delle vetrate, primi tra tutti il fattore solare G che è l'energia termica totale trasmessa dai vetri e il fattore di trasmissione luminosa v che rappresenta la luce naturale introiettata. I test hanno confermato la validità dei moduli sperimentali che, al massimo oscuramento, sono riusciti a schermare il 25% in più di energia termica, rispetto al campione di riferimento e garantire 8÷10 gradi K in meno di temperatura all'interno dei box; mentre, allo stato trasparente hanno garantito l'introspezione di luce naturale.The energy saving, the exploitation of renewable energy, respect for the environment, and living comfort, represent the objectives of the research conducted, relating to the theme of Civil and Environmental Protection, in the building sector. Specifically, innovative glasses have been developed capable of reconciling contrasting aspects such as: guaranteeing the introspection of natural light and at the same time managing the external thermal contributions. The studied prototypes are able to adapt to external stimuli, thanks to organic photochromatic elements that, under the solar radiation, gradually darken by increasing the reflected energy and ensuring the containment of internal temperatures. When the solar radiation drops, they return transparent, letting the sunlight filter through. The ratio of the glasses is the shielding of the thermal energy thanks to the assembly of Low-E glasses, reflecting the infrared radiation, with photochromatic elements able to reflect, activating, the ultraviolet band and a large part of the visible radiation. In experimental campaigns, it was possible to appreciate the performance of experimental glasses, comparing them with those of a low-emission sample module (one of the most performing and widespread products on the market). The advantages of the experimental glasses were quantified, according to the technical procedures of the Standards UNI EN 410/2000 and UNI EN 673/2011, through the evaluation of the characteristic parameters of the windows, first of all the solar factor G which is the total thermal energy transmitted by glass and the light transmission factor v representing introjected natural light. The tests have confirmed the validity of the experimental modules that, at the most obscuring, have managed to screen 25% more thermal energy, compared to the reference sample and guarantee 8 ÷ 10 degrees K less temperature inside the boxes; while, in the transparent state, they guaranteed the introspection of natural light
Consistency analysis of sensor data distribution
No full textIn this paper we analyze the probability of consistency of sensor data distribution systems (SDDS), and determine suitable evaluation models. This problem is typically difficult, since a reliable model taking into account all parameters and processes which affect the system consistency is unavoidably very complex. The simplest candidate approach consists of modeling the state sojourn time, or holding time, as memoryless, and resorting to the well known solutions of Markovian processes. Nevertheless, it may happen that this approach does not fit with some working conditions. In particular, the correct modeling of the SDDS dynamics requires the introduction of a number of parameters, such as the packet transfer time or the packet loss probability, the value of which may determine the suitability of unsuitability of the Markovian model. Candidate alternative solutions include the Erlang phase-type approximation of nearly constant state holding time and a more refined model to account for overlapping events in semi-Markov processes
An edge abstraction layer enabling federated and hierarchical orchestration of CCAM services in 5G and beyond networks
No full textImplementation issues of diffusion-based molecular communications receivers based on transcriptional elements
No full textThe recent research activities on molecular communications systems highlighted impressive potentials for realizing new services in many fields. They include biomedical systems, nanotechnologies, food production and many others. Since the nature of such areas may be extremely different, in terms of geometrical scale, information delivery media, and related technologies, the proposed molecular communication systems include different reception techniques, adapted to the operating environment. In this survey, we focus on systems based on diffusion of signaling molecules, and analyze the main components running in a receiver, namely the reception process and the information decoding mechanism. For each of them, we review the most popular techniques proposed in literature, and discuss the feasibility of using these models to realize receivers based on living cells. In more detail, for the reception process, we discuss the matching between literature models and real reception mechanism. As for the information decoding mechanism, we review and critically discuss its possible implementation through transcriptional elements, which is the main way of implementing processing elements in living cells, highlighting feasibility in term of complexity and decoding time
An Experimental System for Continuous Users Tracking in Emergency Scenarios
No full textIn emergency scenarios, like those following a earthquake, road accident in tunnel, large fire and so on, the possibility to track personnel engaged in providing first aid and rescue services is of paramount importance, also in order to promptly manage unexpected and potentially hazardous situations. While in open areas the precision, accuracy and availability of GPS service is enough in most cases, in partially obstructed environments, such as urban canyon, or indoor, GPS service is not available or the quality of provided estimates could be quite coarse. While the literature reports a lot of solutions able to overcome these limitations of the GPS system in standard settings, in emergency scenarios these solutions could be partially or completely unavailable, raising serious concerns about their suitability in these situations. In this paper, we propose a localization and tracking system based on the usage of IEEE 802.11 technology for augmenting the GPS coverage where it is scarce, and to completely substitute it where it is missing, e.g. indoor. The system is characterized by ease of deployment and usage by non-technical personnel, such as that engaged in rescue services in emergency scenarios. In order to assess the feasibility of the proposed solution, we implemented a proof-of-concepts prototype made up of low-cost commercial off-the-shelf components. The preliminary performance tests we performed confirm the effectiveness of proposed system
Probabilistic Codebook-Based Fault Localization in Data Networks
No full textThis paper shows a codebook-based proposal for identifying simultaneous faults in data networks. It includes three main contributions. The first consists of the Probabilitstic Reduced Search Space Heuristic (PRSSH), which aims to significantly reduce the cardinality of the candidate set of solutions through a so-called compatibility filtering. It is applied to the codebook optimized by the second contribution, which is a solution of the Codebook Optimization problem. It is built on the Weighted Set Covering optimization problem and consists of a heuristic, named Minimum Hamming Distance Increment Maximization Heuristic (MHDIM-HEU). Performance has been evaluated both by applying the proposed techniques to some sample networks, simulated by using the e2e connectivity service model, and by using an experimental codebook generated by using data collected from a real, nation-wide, NGN network. This codebook has been used to simulate fault effects, which were used to analyze the proposal. We compared the PRSSH approach with (a) a previous proposal, named incremental hypothesis update -IHU, (b) the MHDIM-HEU, (c) a random heuristic, and (d) an optimal branch and bound solution (only for very small network size). Results show the effectiveness of our proposals: PRSSH can decrease the false positive rate up to 66% with respect to IHU, with a significantly reduced processing time (two orders of magnitude). As for MHDIM-HEU, for the same target minimum Hamming distance it requires about half of the symptoms of the random heuristic, with performance very close to the optimal approach. As a third contribution, we evaluated the performance of the PRSSH approach over the codebook optimized by means of MHDIM-HEU, in order to evaluate the impact of the codebook compression on the fault localization performance. Numerical results confirm the goodness of the joint application of both approaches
An Extended Java Call Control for the Session Initiation Protocol
No full textIn this paper we propose a functional mapping between Java Call Control (JCC) and Session Initiation Protocol (SIP). We show its effectiveness in enabling easy service design and implementation through experimental results. For this purpose, we have implemented a JCC-SIP Resource Adaptor for a Jain Service Logic Execution Environment (JSLEE). In particular, we have used the Mobicents JSLEE, which is the only existing open source JSLEE implementation. Results, obtained by implementing a typical VoIP service, show both feasibility and good performance of our proposal
Mixed-Sized Biomedical Image Segmentation Based on U-Net Architectures
No full textConvolutional neural networks (CNNs) are becoming increasingly popular in medical Image Segmentation. Among them, U-Net is a widely used model that can lead to cutting-edge results for 2D biomedical Image Segmentation. However, U-Net performance can be influenced by many factors, such as the size of the training dataset, the performance metrics used, the quality of the images and, in particular, the shape and size of the organ to be segmented. This could entail a loss of robustness of the U-Net-based models. In this paper, the performance of the considered networks is determined by using the publicly available images from the 3D-IRCADb-01 dataset. Different organs with different features are considered. Experimental results show that the U-Net-based segmentation performance decreases when organs with sparse binary masks are considered. The solution proposed in this paper, based on automated zooming of the parts of interest, allows improving the performance of the segmentation model by up to 20% in terms of Dice coefficient metric, when very sparse segmentation images are used, without affecting the cost of the learning process
Workflow Engine Integration in JSLEE AS
No full textThis letter proposes a new architectural solution for service creation in JSLEE-compliant platforms, where service business logic can be separated by implementation issues and designed by non JSLEE experts. The novelty consists of integrating a workflow engine inside the development environment of the JSLEE platform, thus allowing simplified management in the development of advanced services and reduction of the time to market of new services
A simulation tool for biological nano-communication systems
No full textBiological nanonetworks is a novel interdisciplinary research area including nanotechnology, biotechnology, and ICT. In this paper, we illustrate a simulation tool designed for modeling communications at nanoscales. This tool is fully adaptable to all nano-scale bearers, used to transport information, which may range from electromagnetic waves to calcium ions. In addition, it can be easily adapted to the interested environment. In this paper, we illustrate an example of the simulator functions by modeling a portion of a lymph node, and simulating the information transfer during the humoral immune response by antibody molecules
- …
