Search results for "FLE"
showing 10 items of 3517 documents
On the assessment of power consumption and critical impeller speed in vortexing unbaffled stirred tanks
2017
Abstract Unbaffled stirred tanks are increasingly recognized as a viable alternative to common baffled tanks for a number of processes and bio-processes where the presence of baffles is undesirable. Notwithstanding the increasing industrial interest towards unbaffled tanks, available experimental information on their behaviour is still very poor, even for important parameters such as mechanical power drawn and critical impeller speed (Ncr) at which the transition between non-aerated (sub-critical regime) and aerated (super-critical regime) conditions occurs. In this work the influence of Reynolds and Froude numbers on power consumption characteristics of unbaffled stirred tanks is presented…
Shear strength of High-strength concrete beams: modeling and design recommendations
2014
Abstract In the present paper, the flexural and the shear resistance of high strength reinforced concrete (HSC) beams with longitudinal bars, in the presence of transverse stirrups is analyzed both theoretically and experimentally. The experimental researches here presented are parts of previous researches carried out by the author. Researches refer to HSC beams with high percentages of steel bars failing in shear and in flexure. From the analytical point of view, a model based on the evaluation of the resistance contribution due to beam and arch actions including bond splitting and concrete crushing failure modes is developed and presented. The model was verified against available experime…
Oscillation dynamics of free vortex surface in uncovered unbaffled stirred vessels
2016
Abstract The main feature of unbaffled stirred tanks is the highly swirling liquid motion, which leads to the formation of a central vortex on the liquid free surface, when the vessel is operated without top-cover (Uncovered Unbaffled Stirred Tanks, UUST). One of the main drawbacks of such vessels, that limits their industrial applicability, is the possible onset of low-frequency sloshing of the free surface. In this work, original data on oscillation dynamics in UUST are presented. In particular, data focus on the oscillation amplitude as well as on their frequency. Data were obtained by means of a novel experimental technique based on digital image analysis. The effect of impeller geometr…
Sustainable Transportation Management System for a Fleet of Electric Vehicles
2015
In the last few years, significant efforts have been devoted to developing intelligent and sustainable transportation to address pollution problems and fuel shortages. Transportation agencies in various countries, along with several standardization organizations, have proposed different types of energy sources (such as hydrogen, biodiesel, electric, and hybrid technologies) as alternatives to fossil fuel to achieve a more ecofriendly and sustainable environment. However, to achieve this goal, there are significant challenges that still need to be addressed. We present a survey on sustainable transportation systems that aim to reduce pollution and greenhouse gas emissions. We describe the ar…
Flexural behaviour of glass panels under dead load and uniform lateral pressure
2013
Abstract In the present paper the experimental results relative to flexural tests on out-of-plane loaded large scale panels made of laminated structural glass are presented and discussed. Glass panels are parts of the structural facade of the Fontanarossa International Airport of Catania (Italy). Panels are mounted on a rigid testing frame and loaded with an uniformly distributed lateral pressure. Two different kinds of tests were carried-out, cyclic and monotonic, able to reproduce the serviceability and the ultimate conditions of the glass panels when subjected to the coupled effects of dead load and horizontal forces, the latter reproducing the wind action. Results obtained focused the h…
Task scheduling control of BGA solder joint process in flexible manufacturing system
2006
This paper describes an open loop control method of the solder joint process in a rework station for faulty printed circuit board (PCBs) containing electronic components in packages ball grid arrays (BGAs). In particular, a mathematical model describing the solder joint process is, first of all, obtained. Then, the desired thermal profile of the junctions BGA-PCB is determined according to the physical constraints of the rework station framework. The control parameters corresponding to the above desired thermal profile are identified using the above mathematical model. Finally, the open loop control algorithm is implemented on the supervisor interface of the rework station in order to carri…
Describing urban soils through a faceted system ensures more informed decision-making
2016
Urban areas are increasing worldwide at a dramatic rate and their soils definitely deserve more attention than they have received in the past. In urban environments, soils potentially provide the same ecosystem services as in rural and wild environments, although in some cases they are depleted of their basic functions, such as when they lose their productive and filtering capacities because of sealing, and become mere supports for infrastructures. In other cases, soils of urban areas acquire new functions that are unique to these environments. Current soil classifications fail to effectively account for the complexity of urban soils and the information that is required for their management…
Eletric vehicles impact using renewable energy
2015
In this moment, the principle topics for the modern world are the reduction of environmental pollution and the production of energy from renewable sources (for example photovoltaic system, wind farm, hydroelectric plants, etc.). This particular attention is determined by different reasons, in particular from the Kyoto Protocol, and from different problems as greenhouse effect, acid rain and climate change. The scope of this work is to study, for different years (1997-2013) in Italy, the production of electric energy from renewable and non-renewable. At a later stage, the attention will be on the consumption of the electric energy divided for different sectors. In particular, we study the po…
Techno-economic analysis of a local district heating plant under fuel flexibility and performance
2017
Brovst is a small district in Denmark. This paper analyses the use of local renewable resources in the district heating systems of Brovst. The present use of fossil fuels in the Brovst district heating plant (DHP) represents an increasing environmental and climate-related load. Therefore, an investigation has been made to reduce the use of fossil fuels for district heating system and make use of the local renewable resources (biogas, solar, and heat pump) for district heating purposes. In this article, the techno-economic assessment is achieved through the development of a suite of models that are combined to give cost and performance data for this district heating system. Local fuels have …
Faculty professional development within the domains of pedagogical content knowledge in engineering
2013
The purpose of this work is to contribute to reflection on the strategies for faculty professional development that promote a culture of scholarly and systematic innovation in engineering education. This paper presents the results of implementing a professional development proposal for engineering professors based on developing their teaching competencies and discusses their relative effectiveness.