824 research outputs found
Structural instability of nonlinear plates modelling suspension bridges: mathematical answers to some long-standing questions
We model the roadway of a suspension bridge as a thin rectangular plate and
we study in detail its oscillating modes. The plate is assumed to be hinged on
its short edges and free on its long edges. Two different kinds of oscillating
modes are found: longitudinal modes and torsional modes. Then we analyze a
fourth order hyperbolic equation describing the dynamics of the bridge. In
order to emphasize the structural behavior we consider an isolated equation
with no forcing and damping. Due to the nonlinear behavior of the cables and
hangers, a structural instability appears. With a finite dimensional
approximation we prove that the system remains stable at low energies while
numerical results show that for larger energies the system becomes unstable. We
analyze the energy thresholds of instability and we show that the model allows
to give answers to several questions left open by the Tacoma collapse in 1940.Comment: 33 page
An Exploratory Study of Field Failures
Field failures, that is, failures caused by faults that escape the testing
phase leading to failures in the field, are unavoidable. Improving verification
and validation activities before deployment can identify and timely remove many
but not all faults, and users may still experience a number of annoying
problems while using their software systems. This paper investigates the nature
of field failures, to understand to what extent further improving in-house
verification and validation activities can reduce the number of failures in the
field, and frames the need of new approaches that operate in the field. We
report the results of the analysis of the bug reports of five applications
belonging to three different ecosystems, propose a taxonomy of field failures,
and discuss the reasons why failures belonging to the identified classes cannot
be detected at design time but shall be addressed at runtime. We observe that
many faults (70%) are intrinsically hard to detect at design-time
Educação corporativa na Embrapa Trigo: uma breve explanação.
Editores técnicos: Joseani Mesquita Antunes, Ana Lídia Variani Bonato, Márcia Barrocas Moreira Pimentel
The meat market in Brazil: a partial equilibrium model
A partial equilibrium model for the meat market is fit to Brazilian data by three stages least squares. The model is consistent with the data and may be used for simulation purposes. In this context we compare model simulations for the near future with the OECD/ Aglink outlook. To illustrate using the model for simulations in policy assessments, we investigate the effect of a relative increase in corn price on the poultry and pork markets, coeteris paribus.Meat markets, elasticities, three stage least squares, simultaneous system of equations., Agribusiness, C 32,
Evolução da produção e do mercado mundial do feijão.
Realizou-se uma avaliação do mercado internacional de feijão, considerando produção, exportação e importação, mostrando o comportamento e oscilações dos principais países
Brazil nut almonds: nutritional and market aspects.
The aim of this study was to estimate the annual growth rate in production and exportation of Brazil nut almonds. Presents information related to the composition of different fatty acids from brazil nut almonds and the human daily intake needs, as well as an analysis of its production, its growth rate during the last 20 years and its export. and the human daily intake needs
Natural wine as an expression of sustainability: an exploratory analysis of Italy’s restaurant industry
Purpose – Although not yet fully defined, natural wine represents a sector that has gained the widespread attention of final consumers and, therefore, also of the restaurant world, because of its promise of sustainability. The objective of this paper is to understand Italian haute cuisine’s interest in natural wine, with the aim of analysing what qualifies this product as sustainable.
Design/methodology/approach – After introducing a theoretical framework based on the concept of
natural wine, a brief paragraph is dedicated to consumer preferences; subsequently, the analysis focusses on a questionnaire given to restaurateurs to determine the impact that natural wine has had in the Italian context. The results try to identify the importance that restaurateurs give to the characteristics of natural wine and their propensity for using such wine in their own businesses.
Findings – The analysis, conducted on a sample of medium-high range restaurants, highlights their strong interest in natural wine, as a result of the final consumers’ attitude towards wine with characteristics attributable to sustainability. The positive perception by restaurateurs is similar across Italy, both geographically and in terms of the size of the restaurant.
Originality/value – The originality of the work is the focus on the world of restaurants. To date, the literature on natural wine remains embryonic and always refers to the final consumer. This research is the first step in a broader study that will involve a greater number of restaurants, extending beyond Italy to all of Europe, with the aim of understanding the real development potential of natural win
Consumo, valor nutritivo e evolução da produção e de mercado mundial de feijão.
Apresentado Painel na 6º Semana de Ensino, Pesquisa e Extensão Universidade Federal de Santa Catarina
- …