1,721,271 research outputs found
Unsaturated polyester-styrene resins: Effect of the catalyst concentration on the kinetic rate and activation energy of the radical crosslinking reactions
No full text
Computer aided engineering for sheet metal forming: definition of a springback quality function
No full textThis paper presents an original formulation for
the evaluation of springback occurrence after sheet
metal stamping. Its aim consists of defining an objective
function able to globally describe springback,
according to specific changes in process or design
variables. This formulation is based on modal analysis
principles and it is applied on Finite Element
simulations of a stamping process. It has been developed
in the general context of design for quality
of sheet metal components. The reasons why such
global index is required are presented by means of a
general state of the art about Computer Aided Engineering
methods for optimizing stamped parts. Then
the basic requirements for its definition are given together
with the proposed formulation. Finally, after
an overview of its potentialities, given by the analysis
of some case studies, conclusion on its adoption and
possible improvements are discussed
New Surface Fitting Approach in Reverse Engineering of Sheet Metal Parts
No full textThe paper is focused on surface reconstruction techniques, developed to enhance the capability of a measurement system set up for analysing sheet-metal parts.
It presents an alternative technique to get accurate results in shape reconstruction in terms of deviation and smoothing. The matrix-like structured data, output of the measure, allows to reconstruct the surfaces following two approaches: Fit curves to sets of aligned points and then blend a surface onto them; fit surfaces on the whole point data set. The first approach is easier to perform because of the wide diffusion, also in the CAD systems, of many robust routines for 2D-curve fitting. The second approach requires a more complex algorithm to surface the 3D point cloud directly but allows to take into account a smoothing factor on the whole data set, that is very useful when more noise is expected on the point cloud
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
A Computer-Aided Design Module To Analyse Manufacturing Configurations of Bent and Hydroformed Tubes
No full textThis paper presents a computer-aided design (CAD) module able to analyze different manufacturing configurations of tubes used in mechanical assemblies, such as exhaust system manifolds. It can be included in the knowledge-based expert system category and has been implemented into a CAD platform as a dedicated module able to take into account manufacturing requirements related to tube bending, hydroforming, and cutting. The expert's knowledge, in terms of set of rules and criteria, has been implemented by means of the automation tools of CATIAV5R10 according to the socalled methodological formal approach. The resulting module is able to join different tubes starting from their geometrical models, obtaining a set of manufacturing alternatives. Each of them is verified with respect to collisions with a bending machine and also in terms of hydroforming process feasibility. Only those solutions that satisfy these checks are accepted as feasible and ranked according to three evaluation criteria related to manufacturing cost and easiness. The system is completely automatic and able to analyze more than 100 different configurations in <10 min. The feasible solutions are saved as CAD model to allow FEA of hydroforming and other possible CAE activities. Unfeasible solutions are deleted but reported and documented in a log file. The feasible solution rank is given in a table and has been developed according to a multicriteria approach to make optimal solution detection easier. The proposed test case aims to show and discuss these capabilities. By this module, two or more components of the exhaust system manifold can be manufactured in one stroke as a single component, starting from the same pipe and next trimmed to obtain the desired final parts. This capability can be used to reduce scraps and improve cycle time of the manufac-turing process. Copyright © 2007 by ASME
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
A free lance am I [music] : or the soldier of fortune /
No full textH & C. 1538 (Publisher number). For voice and piano.; Caption title.; "Sung ... by Signor Federici, also by Signor Lancelotti"--Cover.; First line of chorus: My sword by my side.; First line of verse: The clash of arms.; Also available online http://nla.gov.au/nla.mus-vn4503855.Soldier of fortun
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