196 research outputs found
Influence of Fuel Injection, Turbocharging and EGR Systems Control on Combustion Parameters in an Automotive Diesel Engine
Indicated pressure diagrams were measured during experimental campaigns on the control of fuel injection, turbocharging and hybrid exhaust gas recirculation systems in an automotive downsized diesel engine. Three part load operating conditions were selected for four test sets, where strategies aimed at the reduction of NOX emissions and fuel consumption, limiting penalties in soot emissions and combustion noise were applied to the selected systems. Processing of in-cylinder pressure signal, its first derivative and curves of rate of heat release allowed to evaluate seven parameters related to combustion centre and duration, maximum values of pressure, heat release and its first derivative, heat released in the premixed phase and a combustion noise indicator. Relationships between these quantities and engine operating, energy and environmental parameters were then obtained referring to the four test sets. In the paper, the most significant links are presented and discussed, aiming at a better understanding of the influence of control variables on combustion process and the effects on engine behavior. The proposed methodology proved to be a consistent tool for this analysis, useful for supporting the application of alternative fuels or advanced combustion modes
Effects of rail pressure control on fuel consumption, emissions and combustion parameters in a turbocharged diesel engine
The influence of rail pressure control on fuel consumption, emissions and combustion in an automotive downsized turbocharged diesel engine was investigated, considering different operating modes in three-part load working conditions. These modes were selected according to the results of a previous step of the study, where low NOX and fuel consumption levels were obtained managing a hybrid exhaust gas recirculation (EGR) system and the turbocharger variable nozzle turbine (VNT). Aiming at limiting observed soot penalties, increased values of rail pressure were applied, deepening the interactions with engine-controlled sub-assemblies and the related variations in operating, environmental, energy and combustion parameters. At low levels of engine speed and load, major reduction in NOX emissions and fuel consumption were observed, with acceptable soot and noise combustion increase, while turbocharger speed was also enhanced. No variations in fuel consumption were achieved at higher load and speed, while soot penalty remained significant. A simplified method to describe and model engine behaviour and combustion process was also developed, defining linear relationships between rail pressure and engine quantities, including a wide set of combustion parameters derived from in-cylinder pressure diagrams and heat release curves
Recommended from our members
Web–based Participatory GIS with data collection on the field – A prototype architecture
The rise of Web 2.0 and the current, unprecedented diffusion of mobile devices have laid new foundations for the development of PGIS (Participatory GIS). This study evaluates the possibility of exploiting FOSS (Free and Open Source Software) tools to build up a PGIS prototype providing Web publication of user field-collected data. Besides increasing public awareness and collaboration, user-generated content should also enlarge the knowledge of specific phenomena up to the local level. A prototype architecture was designed and tested in relation to a simple, planning-related case study, i.e., the report of road pavement damages. Open Data Kit suite was used to gather georeferenced multimedia data using mobile device sensors (e.g., the GPS) and to store them into a PostgreSQL database with PostGIS spatial extension. Data was then Web-published using GeoServer. Web access was finally enabled from both traditional desktop-computers and mobile platforms through ad hoc OpenLayers and Leaflet clientside solutions. The architecture provided support for FOSS applicability within the typical PGIS-related tasks, from field survey to data storage, management and dissemination on the Internet. This bottom-up communication paradigm, which exploits real-time, freely available user contributions, can become a potentially precious tool for making decision-processes more democratic, faster and ultimately better
Neonatal screening for glucose-6-phosphate dehydrogenase deficiency fails to detect heterozygote females
We examined glucose-6-phosphate dehydrogenase (G6PD) deficiency in north-eastern Italian Caucasian neonates detected by neonatal screening, in order to measure the incidence of heterozygote females detected by neonatal screening, and to estimate the near-true total incidence. A total of 85,437 Caucasian neonates, born between January 2000 and December 2001, have been enclosed in the study. The total incidence of the disease, measured by fluorescent method, is 0.9‰; the total incidence, calculated by Hardy-Weinberg law, is 4.8‰. The frequency of missed females is 93% of total females expected with G6PD deficiency; most of them are very likely heterozygous females. The sensitivity of the fluorescent method might be not sufficient to detect all females. Since heterozygote females might develop the symptoms of G6PD deficiency later, these results suggest that the G6PD neonatal screening may not be helpful in preventing disease in female
Positional accuracy assessment of the OpenStreetMap buildings layer through automatic homologous pairs detection: the method and a case study
OpenStreetMap (OSM) is currently the largest openly licensed collection of geospatial data. Being OSM increasingly exploited in a variety of applications, research has placed great attention on the assessment of its quality. This work focuses on assessing the quality of OSM buildings. While most of the studies available in literature are limited to the evaluation of OSM building completeness, this work proposes an original approach to assess the positional accuracy of OSM buildings based on comparison with a reference dataset. The comparison relies on a quasi-automated detection of homologous pairs on the two datasets. Based on the homologous pairs found, warping algorithms like e.g. affine transformations and multi-resolution splines can be applied to the OSM buildings to generate a new version having an optimal local match to the reference layer. A quality assessment of the OSM buildings of Milan Municipality (Northern Italy), having an area of about 180 km2, is then presented. After computing some measures of completeness, the algorithm based on homologous points is run using the building layer of the official vector cartography of Milan Municipality as the reference dataset. Approximately 100000 homologous points are found, which show a systematic translation of about 0.4 m on both the X and Y directions and a mean distance of about 0.8 m between the datasets. Besides its efficiency and high degree of automation, the algorithm generates a warped version of OSM buildings which, having by definition a closest match to the reference buildings, can be eventually integrated in the OSM database
Web Mapping technologies for the valorization of slow tourism: the Via Regina project
The practice of slow tourism denotes a sustainable way of living the territory based on environmentally-friendly forms of transportation, the appreciation of nature and the rediscovery of local history and cultural identity. Technological advancements in ICT, mostly in the domain of GIS, nowadays represent an essential mean to give new insights to this kind of activities. This work presents a rich implementation of Free and Open Source Software (FOSS) Web Mapping technologies to valorize slow tourism in the charming naturalistic area of Via Regina. This is an ancient cultural route overlooking Lake Como (Northern Italy) and defining a system of slow mobility paths – ideal for hiking and/or biking – which spans the mountainous region at the border between Italy and Switzerland. First, a mobile app is developed which allows tourists to report a wide range of points of interest while travelling around the paths. Along with a huge amount of other geospatial data (e.g. the authoritative data provided by local administrations and the paths surveyed by hikers associations), this crowdsourced information is made available within a standard 2D Web viewer. Services for routing as well as the computation of terrain profiles of paths are also implemented. Finally a virtual globe-based platform provides 3D data visualization while also offering a set of collaborative functionalities. Besides proving the efficiency of FOSS, the work provides a modern reinterpretation of the slow tourism concept which, along with the current technological possibilities, can simplify and at the same time enrich the travellers' experience
Volunteered Geographic Information For Water Management: A Prototype Architecture
Driven by Web 2.0 technology and the almost ubiquitous presence of mobile devices, Volunteered Geographic Information (VGI) is knowing an unprecedented growth. These notable technological advancements have opened fruitful perspectives also in the field of water management and protection, raising the demand for a reconsideration of policies which also takes into account the emerging trend of VGI. This research investigates the opportunity of leveraging such technology to involve citizens equipped with common mobile devices (e.g. tablets and smartphones) in a campaign of report of water-related phenomena. The work is carried out in collaboration with ADBPO - AutoritĂ di bacino del fiume Po (Po river basin Authority), i.e. the entity responsible for the environmental planning and protection of the basin of river Po. This is the longest Italian river, spreading over eight among the twenty Italian Regions and characterized by complex environmental issues. To enrich ADBPO official database with user-generated contents, a FOSS (Free and Open Source Software) architecture was designed which allows not only user field-data collection, but also data Web publication through standard protocols. Open Data Kit suite allows users to collect georeferenced multimedia information using mobile devices equipped with location sensors (e.g. the GPS). Users can report a number of environmental emergencies, problems or simple points of interest related to the Po river basin, taking pictures of them and providing other contextual information. Field-registered data is sent to a server and stored into a PostgreSQL database with PostGIS spatial extension. GeoServer provides then data dissemination on the Web, while specific OpenLayers-based viewers were built to optimize data access on both desktop computers and mobile devices. Besides proving the suitability of FOSS in the frame of VGI, the system represents a successful prototype for the exploitation of user local, real-time information aimed at managing and protecting water resources
NASA World Wind: virtual globe for an open smart city
In this article, firstly the open source framework NASA World Wind is introduced. NASA World Wind comes mainly with two versions. The Java version is well established in the market and has many customers. On the other hand the new version, which is the Web version, Web World Wind, is still at the dawn of development cycle, with many features implemented and already used in several applications, with a great future ahead. Following the introduction of NASA World Wind, the features available in the Web World Wind are listed and a short comparison with Cesium library is provided. Additionally, an application developed in the smart cities context with Web World Wind is described
School of Phlebological Surgery: an innovative training under the auspices of the Italian Society of Surgery and of Vascular and Endovascular Surgery
The Authors share some insights on the role of Phlebology in Italy and present the school of Phlebological Surgery, highlighting the importance of knowledge spead and inclusivity
Apps and Web mapping: innovative tools to promote slow tourism along Via Regina
Overlooking the West coast of Lake Como in Northern Italy, Via Regina has represented a fundamental European trade and pilgrim route since the ancient Roman times. The dense system of paths departing from it and spanning the beautiful mountainous region at the border between Italy and Switzerland makes this area an awesome destination for slow tourism activities, which consist of sustainable forms of transportation, appreciation of nature and (re)discovery of the local history and culture. In the frame of the Interreg project “The Paths of Regina – Crossborder paths linked to Via Regina”, which involves Italian and Swiss universities, cultural associations, local agencies and administrations, this work aims at valorizing slow tourism in the Via Regina region through the creation of open source Web Mapping applications leveraging also the modern fields of crowdsourcing and virtual globes
- …