Search results for "95"
showing 10 items of 2244 documents
Design of Wideband MIMO Car-to-Car Channel Models Based on the Geometrical Street Scattering Model
2012
Published version of an article in the journal: Modelling and Simulation in Engineering. Also available from the publisher at: http://dx.doi.org/10.1155/2012/264213 Open access We propose a wideband multiple-input multiple-output (MIMO) car-to-car (C2C) channel model based on the geometrical street scattering model. Starting from the geometrical model, a MIMO reference channel model is derived under the assumption of single-bounce scattering in line-of-sight (LOS) and non-LOS (NLOS) propagation environments. The proposed channel model assumes an infinite number of scatterers, which are uniformly distributed in two rectangular areas located on both sides of the street. Analytical solutions a…
Analysis of Offshore Knuckle Boom Crane - Part One: Modeling and Parameter Identification
2013
This paper presents an extensive model of a knuckle boom crane used for pipe handling on offshore drilling rigs. The mechanical system is modeled as a multi-body system and includes the structural flexibility and damping. The motion control system model includes the main components of the crane's electro-hydraulic actuation system. For this a novel black-box model for counterbalance valves is presented, which uses two different pressure ratios to compute the flow through the valve. Experimental data and parameter identification, based on both numerical optimization and manual tuning, are used to verify the crane model. The demonstrated modeling and parameter identification techniques target…
Design And Characterization Of Automated Color Sensor System
2017
Abstract The paper presents a color sensor system that can process light reflected from a surface and produce a digital output representing the color of the surface. The end-user interface circuit requires only a 3-bit pseudo flash analog-to-digital converter (ADC) in place of the conventional/typical design comprising ADC, digital signal processor and memory. For scalability and compactness, the ADC was designed such that only two comparators were required regardless of the number of color/wavelength to be identified. The complete system design has been implemented in hardware (bread board) and fully characterized. The ADC achieved less than 0.1 LSB for both INL and DNL. The experimental r…
Thermal stress analysis of different full and ventilated disc brakes
2015
During the braking phase, the heat produced by friction between pads and disc cannot be entirely dissipated. Consequently, the brake disc, especially if very hard braking occur, can accumulate large amounts of heat in a short time so producing high gradients of temperature on it. Under these conditions, functionality and safety of the brake system can be compromised. The object of this study is to investigate, under extreme working conditions, the thermomechanical behaviour of different brake rotors in order to evaluate their efficiency and stability and to identify any compromising weakness on them. In particular, by means of FEM thermo-mechanical coupled analyses, one full disc and three …
Composite Building Materials: Thermal and Mechanical Performances of Samples Realized with Hay and Natural Resins
2017
Unidad de excelencia María de Maeztu MdM-2015-0552 Recent years have seen an increasing public interest in issues related to energy saving and environmental pollution reduction in the building sector. As a result, many directives have been issued, the most important being the Directive 2010/31/EU (EPBD Recast) on the energy performance of buildings, which requires that "Member States shall ensure that by 31 December 2020 all new buildings are nearly zero-energy buildings". This goal can be obtained not only by reducing energy demand for heating and cooling, but also, for example, by improving building envelope performances. In this work, a first analysis of the thermal and structural behavi…
Strategic Vision of a Euro-Mediterranean Port City: A Case Study of Palermo
2013
Italian harbours assume a decisive role in order to develop a Euro-Mediterranean web for maritime transportation. The geostrategic position of the Italian peninsula can be seen as a logistic platform at the centre of the maritime trades in the Mediterranean area, giving to its port cities the role of gateway of economic flows. The port poles, meant as hubs, are able to attract investments and create economic growth and territorial development through new operative models of urban usage and management. The management policies have to consider the environmental characteristics and distinctive features, respecting the identity of the places as concrete evidence of history, a source of intellec…
An interpretive framework for assessing and monitoring the sustainability of school gardens
2016
School gardens are, increasingly, an integral part of projects aiming to promote nutritional education and environmental sustainability in many countries throughout the world. In the late 1950s, FAO (Food and Agriculture Organization) and UNICEF (United Nations Children's Fund) had already developed projects to improve the dietary intake and behavior through school and community gardens. However, notwithstanding decades of experience, real proof of how these programs contribute to improving sustainability has not been well-documented, and reported findings have mostly been anecdotal. Therefore, it is important to begin a process of collecting and monitoring data to quantify the results and …
Evaluating the Sustainability in Complex Agri-Food Systems: The SAEMETH Framework
2015
During the last few years, the definition of sustainability and the translation of its general principles into practical and operative tasks have come into the foreground of scientific research and political agendas throughout the world. The understanding and the evaluation of the environmental, social and economic performances of complex agricultural food systems is probably the real challenge, and the design of more sustainable alternatives has been recognized as necessary for a correct territorial management. This study’s primary goal is the proposition of an interpretive structure “Sustainable Agri-Food Evaluation Methodology” (SAEMETH), able to guide the evaluation of the sustainabilit…
Identification of Defensive Performance Factors in the 2010 FIFA World Cup South Africa
2016
The aim of this study was to determine the efficacy of defensive play in elite football, to identify variables associated with the direct recovery of ball possession, and to propose a model for predicting the success of defensive transitions. We analyzed 804 transitions in the final stages of the Fedération Internationale Football Association (FIFA) World Cup 2010, and investigated the following variables using univariate, bivariate, and multivariate analyses: duration of defensive transition, possession loss zone, position of players at the start and end of the defensive transitions, defensive organization, general defensive approach, time of the match, position of defense, zone in which t…
Performances Comparison for a Rotating Shaft Suspended by 4-Axis Radial Active Magnetic Bearings via 𝜇 -Synthesis, Loop-Shaping Design, and Sub ( 𝐻…
2011
The control systems applied on active magnetic bearing are several. A perfect levitation is characterized by maintaining the operating point condition that is characterized by the center of stator coincident with the geometric center of shaft. The first controller implemented for this purpose is PID controller that is characterized by an algorithm that leads the amplifier to produce control current until the operating point condition is not reached, this is obtained by an integration operator. The effect of an integrator is essential but not necessary for a centered levitation for example in the robust control characterized by a dynamic model depended on plant of system so that it depends o…