Search results for "Proa"
showing 10 items of 1834 documents
A theoretical and methodological framework for the analysis and measurement of environmental heritage at local level
2017
Abstract The study aims to assess the lived experience and the environmental heritage perceived level by residents of an high complexity rural area, and which is, in this context, the role played by production of renewable energies. The paper introduces the concept of rural capital as an effective tool for environmental heritage analysis and measurement. The proposed theoretical and methodological approach allows, in fact, its analysis in order to understand what dimensions related to territoriality are connected to the perceived level of environmental heritage at local level. Translated into operational terms, the methodology has resulted in an empirical analysis of a rural and inner area …
Steel and composite tied-arch bridges: a conceptual approach to structural design
2021
The behaviour of tied-arch bridges with composite decks (bowstring bridges) is overly sensitive to the different choices made by the designer in the first phases of the conceptual approach, mainly in the design of the arch and the deck. The geometry of the arch shape, the design of the arch–tie joint and the construction sequence can significantly modify the global behaviour in terms of stress state and deformed configuration. After a general discussion on the different parameters affecting the behaviour of bowstring bridges with steel–concrete composite decks, the consequences of choices made in the conceptual design phases are discussed, analysing the effects of each choice on the global…
U.I.R.D.A. – Unbuilt Italian Rationalism Digital Archive
2018
For twenty years, the architecture of Italian rationalism through the digital modelling has been investigated. Very often, the production of a model and the consequent representation of tridimensional views, in many case studies, as outcome of the research on architecture have been considered. Actually, the digital model, intended as a critical tool, has to be conceived as a ‘starting point' for graphic analysis of architecture and not as the outcome. Indeed, it is associated to other graphics, sometimes not ‘deducted' from the model, useful for the understanding/translation of architecture. The construction of the model is not the construction of a simple image, operation, which is often c…
The evaluation of springback in 3D stamping and coining processes
1998
Abstract An effective predictive technique of the elastic springback in a fully 3D 90° V-punch V-die bending process is presented. This is based on a combined approach in which an explicit finite element code was used to simulate the loading phase of the process whilst an implicit procedure was used to analyse the springback phase. Two different punches with a nose radius of 4 and 8 mm were used. An increase in the springback ratio with the coining load was observed with the lower nose radius. Conversely, an increase in the springback ratio with the coining load up to a peak value (>1), corresponding to a force of about 20 kN, followed by a decrease in the springback ratio with increasing t…
Preparation of photocatalysts by chemical methodologies
2021
Abstract The synthesis of photocatalytic materials is an important task for obtaining better results in terms of activity and/or selectivity in photocatalysis. This chapter reports an overview of the main methodologies using physical techniques to obtain bulky, supported powders or films and coatings to be used as heterogeneous photocatalysts. The classical chemical methodologies for the preparation of photocatalytic materials are presented in the previous chapter, so the information presented here complements the aforementioned one. Materials scientists and engineers have made significant progresses in the improvement of methods of synthesis of nanomaterial solids by developing different a…
Stability analysis of rotor whirl under nonlinear internal friction by a general averaging approach
2016
The two main sources of internal friction in a rotor-shaft system are the shaft structural hysteresis and the possible shrink-fit release of the assembly. The internal friction tends to destabilize the over-critical rotor running, but a remedy against this effect may be provided by a proper combination of some external damping in the supports and an anisotropic arrangement of the support stiffness, or at most by the support damping alone, depending on the system geometry. The present analysis reported here considers a general asymmetric rotor-shaft system, where the rotor is perfectly rigid and is constrained by viscous–flexible supports having different stiffnesses on two orthogonal plane…
A predictive maintenance policy with imperfect monitoring
2010
For many systems,failure is a very dangerous or costly event. To reduce the occurrence of this event,it is necessary to implement a preventive maintenance policy to replace the critical elements before failure.Since elements do not often exhibit incipient faults, they are replaced before a complete exploiting of their useful life.To conjugate the objective of exploiting elements for almost all their useful life with the objective to avoid failure,condition based and,more recently,predictive maintenance policies have been proposed.This paper deals with this topic and proposes a procedure for the computation of the maintenance time that minimizes the global maintenance cost.By adopting a stoc…
Decoding the Japanese Lean Production System according to a Viable Systems Perspective
2012
The increase in the complexity and variability of the business environment, due to constant and rapid changes in markets, calls for more flexible and effective production systems. Of the most valuable production systems, the Japanese lean production system (LPS) is the best known and studied, but is still not the most widely applied with success outside Japan. The reason for the low level of success of lean production outside its native country is the lack of understanding of the strong interactions which hold between enterprises and business systems. In order to fill this gap in our knowledge, we investigate the systemic interactions according to the Viable System View. To develop our anal…
The Advantages of the Network-based Electronic Teaching Package by the Implementation of English for Specific Purposes Course
2015
Abstract The article analyses the advantages of English for Specific Purposes teaching of the fourth year students majoring in “Electrical and Power Engineering” at National Research Tomsk Polytechnic University by means of the network-based electronic teaching package. This paper analyzes the structural content of the network-based electronic teaching package, shows the key approaches used to develop this tool and focuses on the description of its main components. The conclusions made are based on the results obtained over a three year period (2012-2015) of the network-based electronic teaching package use.
Improving Maintenance Activities of Machine Tools
2013
The paper follows the current trends in the field of maintenance, proposing approaches that fit in the concept of Total Productive Maintenance (TPM). First it is presented a new proposal for tracking in-service machine tools. This is based on the identification of three operating states: good running condition, state of repair and stationary state. During the stationary state there are differentiated two distinct types of stops: natural stays and unproductive stays (those who often produce considerable losses). Based on the information contained in the records made for tracking the operation of machine tools there are proposed formulas for calculating some operational indicators and practic…