1,199 research outputs found
Impacts of safety on the design of light remotely-piloted helicopter flight control systems
This paper deals with the architecture definition and the safety assessment of flight control systems for light remotely-piloted helicopters for civil applications. The methods and tools to be used for these activities are standardised for conventional piloted aircraft, while they are currently a matter of discussion in case of light remotely-piloted systems flying into unsegregated airspaces. Certification concerns are particularly problematic for aerial systems weighing from 20 to 150 kgf, since the airworthiness permission is granted by national authorities. The lack of specific requirements actually requires to analyse both the existing standards for military applications and the certification guidelines for civil systems, up to derive the adequate safety objectives. In this work, after a survey on applicable certification documents for the safety objectives definition, the most relevant functional failures of a light remotely-piloted helicopter are identified and analysed via Functional Hazard Assessment. Different architectures are then compared by means of Fault-Tree Analysis, highlighting the contributions to the safety level of the main elements of the flight control system (control computers, servoactuators, antenna) and providing basic guidelines on the required redundancy level
Access to Healthcare as a New Commons: Telemedicine as a Strategy for Providing Value-Based Healthcare Services in Rural Areas
Commons is a general term that refers to a resource shared by a group of people. Over the years, scholars have identified two generations of commons. The first generation of commons was about sharing of physical things; the second one is about intangible commons pool resources such as science and culture. These generally can be recognized as "rights" (Hess 2008). Among the various New Commons sectors there is medical and health. In the perspective of guaranteeing the right of Health, the âAccess to Healthcareâ could be considered as a New Commons provided by worldwide National Healthcare Systems (NHS), However, healthcare sector is characterized by plenty of stakeholders with myriad, often, conflicting goals. The value-based approach (Porte, 2010) attempts to introduce a new universal language in healthcare management around the value for the patient that reconcile all stakeholdersâ interests. The goal of this approach is to improve the outcome and increase the number of treatments. This aim is very difficult to be enriched for rural residents; when patients live in remote areas, providing them with valuable medical care can be considered a hard challenge for the NHS, which has to be addressed also by the employment of new healthcare strategies and technologies. Defined as "a new healthcare delivery process provided when patient and professional are not physically in the same place" (Italian Ministry of Health, 2014), telemedicine could be seen as an answer to this challenge. Accordingly, this study aims at discovering if telemedicine employment can be effectively considered as a successful strategy to improve healthcare in location far from specialized hospital, enhancing the New Commons âAccess to careâ.
A statistical-based narrative review of the literature was conducted in the field of telemedicine, with the aim to understand which experiences of telemedicine applications have got successful results as support of healthcare delivering in rural locations. With regards to rural and remote areas, several Authors recognized telemedicine-based strategies as a method to facilitate the access to healthcare in different medical disciplines. In particular, many studies highlight that telemedicine improves patient care by increasing the capacity of the rural clinician to manage patient locally, minimizing time away to support networks and reducing unnecessary transfers. Telemedicine could also be considered a cost-effective method whose outcomes remain similar (if not better) in quality to âstaffedâ services, whose infrastructural costs could be easily paid-back
The quantum-classical transition in thermally seeded parametric downconversion
We address the pair of conjugated field modes obtained from
parametric-downconversion as a convenient system to analyze the
quantum-classical transition in the continuous variable regime. We explicitly
evaluate intensity correlations, negativity and entanglement for the system in
a thermal state and show that a hierarchy of nonclassicality thresholds
naturally emerges in terms of thermal and downconversion photon number. We show
that the transition from quantum to classical regime may be tuned by
controlling the intensities of the seeds and detected by intensity
measurements. Besides, we show that the thresholds are not affected by losses,
which only modify the amount of nonclassicality. The multimode case is also
analyzed in some detail.Comment: 12 pages, 3 figure
The quantum-classical transition in thermally seeded parametric downconversion
We address the pair of conjugated field modes obtained from
parametric-downconversion as a convenient system to analyze the
quantum-classical transition in the continuous variable regime. We explicitly
evaluate intensity correlations, negativity and entanglement for the system in
a thermal state and show that a hierarchy of nonclassicality thresholds
naturally emerges in terms of thermal and downconversion photon number. We show
that the transition from quantum to classical regime may be tuned by
controlling the intensities of the seeds and detected by intensity
measurements. Besides, we show that the thresholds are not affected by losses,
which only modify the amount of nonclassicality. The multimode case is also
analyzed in some detail.Comment: 12 pages, 3 figure
Development of a simulation platform of all-electric aircraft on-board systems for energy management studies
This paper deals with the development of a simulation platform for the dynamic analysis of systems characterised by different physical domains. The research has been carried out
in the context of the EC-funded Clean Sky Joint Technology Initiative (Green Regional Aircraft/All-Electric Aircraft domain). In particular, the objective of the research is focused
on the on-board systems of new All-Electric Aircraft, where a crucial design point is related to the electrical energy management. In the âall-electricâ concept, where pneumatic and
hydraulic power systems are eliminated to improve aviation costs and environmental impact, the dynamics of electrical power absorptions is to be characterised and managed to avoid
excessive peaks with respect to generators capabilities. The paper describes the architecture of a Matlab/Simulink simulation platform developed in order to design and validate of the
electrical energy management logics, which lead up to 32% reduction of the maximum power request for the case study considered. Thanks to an approach based on a mixing of cosimulation
and S-function compiling, the platform integrates models coming from different environments (AMESim, Dymola/Modelica), and developed by various partners/specialists
Wintertime thermal performance of green façades in a mediterranean climate
The increasing environmental issues have afforded opportunities for a widespread application of green systems in urban areas. Greening the building with green roofs and vertical green systems can be a design and retrofitting strategy to improve building energy performance in summer and in winter. Research efforts have been mainly concentrated on their energy saving function during warm periods. Green façades have a great application potential thanks to the space available in urban environment. The effect of green façades on building energy performance has been studied mainly for warm periods. In order to evaluate the effect during cold periods, an experiment was conducted in Bari, Italy, for two years. Pandorea jasminoides variegated and Rhyncospermum jasminoides were tested as evergreen climbing plants on walls; a third wall was used as control. The night-time temperature of the covered wall was higher than the uncovered wall temperature by up to 3.5°C, thanks to the presence of plants. The thermal barrier function performed by the vegetation layer was analysed. The influence of outdoor air temperature, relative humidity and wind velocity on the façades thermal effect during night-time was investigated. The experimental test demonstrated that both Pandorea jasminoides variegated and Rhyncospermum jasminoides are suitable for green façades in the Mediterranean climatic area during winter. The use of the green façades allowed increasing the thermal performance of the walls during night-time. They also reduced the surface temperature changes throughout the day
Implementing a GIS-Based Digital Atlas of Agricultural Plastics to Reduce Their Environmental Footprint: Part II, an Inductive Approach.
Plastic pollution, largely perceived by the public as a major risk factor that strongly impacts sea life and preservation, has an even higher negative impact on terrestrial ecosystems. Indeed, quantitative data about plastic contamination on agricultural soils are progressively emerging in alarming ways. One of the main contributors to this pollution involves the mismanagement of agricultural plastic waste (APW), i.e., the residues from plastic material used to improve the productivity of agricultural crops, such as greenhouse covers, mulching films, irrigation pipes, etc. Wrong management of agricultural plastics during and after their working lives may pollute the agricultural soil and aquifers by releasing macro-, micro-, and nanoplastics, which could also enter into the human food chain. In this study, we aimed to develop a methodology for the spatial quantification of agricultural plastics to achieve sustainable post-consumer management. Through an inductive approach, based on statistical data from the agricultural census of the administrative areas of the Italian provinces, an agricultural plastic coefficient (APC) was proposed, implemented, and spatialized in a GIS environment, to produce a database of APW for each type of crop. The proposed methodology can be exported to other countries. It represents valuable support that could realize, in integration with other tools, an atlas of agricultural plastics, which may be a starting point to plan strategies and actions targeted to the reduction of the plastic footprint of agriculture
Implementing a GIS-based Digital Atlas of Agricultural Plastics to Reduce Their Environmental Footprint. Part I: A Deductive Approach.
The agricultural sector has benefitted over the last century from several factors that have led to an exponential increase in its productive efficiency. The increasing use of new materials, such
as plastics, has been one of the most important factors, as they have allowed for increased production in a simpler and more economical way. Various polymer types are used in different
phases of the agricultural production cycle, but when their use is incorrectly managed, it can lead to different environmental impacts. In this study, an applied and simplified methodology to manage agricultural plastics monitoring and planning is proposed. The techniques used are based on quantification through the use of different datasets (orthophotos and satellite images) of the areas covered by plastics used for crop protection. The study area chosen is a part of the Ionian Coast of Southern Italy, which includes the most important municipalities of the Basilicata Region for fruit and vegetable production. The use of geographical techniques and observation methodologies, developed in an openâsource GIS environment, enabled accurate location of about 2000 hectares of agricultural land covered by plastics, as well as identification of the areas most susceptible to the accumulation of plastic waste. The techniques and the model implemented, due to its simplicity of use and reliability, can be applied by different local authorities in order to realize an Atlas of agricultural plastics, which would be applied for continuous monitoring, thereby enabling the upscaling of future social and ecological impact assessments, identification of new policy impacts, market searches, etc
Greenhouse localized heating powered by a polygeneration system
Energy consumption in greenhouse heating could reach up to 90% of the total energy requirement depending on the type of greenhouse, environmental control equipment and location of the greenhouse. The use of climate conditioning technologies that exploit renewable energy and the application of passive systems to improve the energy efficiency and the sustainability of the greenhouse sector are recommended. During winter 2020-2021, an experimental test was carried out at the University of Bari in a Mediterranean greenhouse heated by a polygeneration system, composed of a solar system and an air-water heat pump. Three localized heating systems were tested to transfer thermal energy close to plants of Roman lettuce. Heating pipes were placed inside the cultivation substrate in the underground pipe system and on the cultivation substrate in the laid pipe system. The third system consists of metal plates heated by steel tubes and placed in the aerial area of plants. A weather climatic station and a sensor system interfaced with a data logger for continuous data acquisition and storage were used. The plate system was the best for air temperature rising, as it allowed an increase of 3.6% compared to the set-up without any localised heating system. The underground pipe system was the best for the soil heating, as it achieved a temperature increase of 92%. Localized soil heating systems contributed significantly to an earlier harvest by almost 2 weeks
Reduction of Evapotranspiration in Microenvironment Conditions of Table Grape Vineyards Protected by Different Types of Plastic Covers
Saving water is a major challenge to increase environmental sustainability, particularly in semi-arid regions where most table grapes are produced. Water use is driven by atmospheric demand, which combines effects of solar radiation (prominent factor), wind, air temperature and humidity. Covering table grapes with transparent plastics is spread in many regions. Covers lower incoming solar radiation and wind speed, changing air temperature and humidity. This study assessed the effects of two plastic covers on reference evapotranspiration (ET0 ) in comparison to the open field. For two years, two vineyards (cv. Victoria) trained to overhead trellis systems (tendone) were covered with two transparent polyethylene sheets: an agrotextile fabric (C), and a commercial film (S). The sheet spectrophotometric properties were analyzed and the radiometric coefficients calculated. Micrometeorological data were recorded in the covered vineyards and in a nearby uncovered one. ET0 was calculated for June and July using the simplified PenmanâMonteith equation. The coefficient of transmissivity to total photosynthetic radiation, a proxy of net radiation, was 73% for cover C and 83% for cover S. On average, ET0 decreased by 35% under cover C and 31% under cover S. Hence, in addition to providing protection from external agents, covers represent a valid tool for saving water in table grape viticulture; nevertheless, their radiometric properties should be considered and optimized to better achieve this goal
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