A study on human error in the interaction with the computer systems

The term human factor is used by professionals of various fields meant for understanding the behavior of human beings at work. The human being, while developing a cooperative activity with a computer system, is subject to cause an undesirable situation in his/her task. This paper starts from the principle that human errors may be considered as a cause or factor contributing to a series of accidents and incidents in many diversified fields in which human beings interact with automated systems. We propose a simulator of performance in error with potentiality to assist the Human Computer Interaction (HCI) project manager in the construction of the critical systems. © 2011 Springer-Verlag.

Viabilidade de uso de um misturador para a análise de propriedades reológicas de produtos alimentícios

Pós-graduação em Agronomia (Energia na Agricultura) - FCA

Mapeamento geoambiental com imagem de satélite do Vale do Paraíba

Pós-graduação em Geociências e Meio Ambiente - IGCE

A gestão da informação e do conhecimento como subsídios para a geração de inovação

Pós-graduação em Ciência da Informação - FFC

Influência do tratamento térmico sobre a tenacidade de um aço com AISI SAE 1045 com médio teor de carbono, avaliada por ensaios de impacto

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Research on policies and institutions to support small and medium scale enterprise in the Caribbean: Trinidad adn Tobago report

The Government of Trinidad and Tobago continues to provide support to SMEs in order to enhance their international competitiveness. The increasing effects of globalization and the reality of several trade agreements require that local businesses attain and maintain a level of competitiveness which ensures their continued survival and growth. This report examines in detail the policy environment within which these enterprises operate. It also examines the role of the key implementing agencies such as the BDC and NEDCO for government’s policy on the sector and also the role of the respective line ministries. These organizations strive to deliver value added technical, financial and export promotion services to its clients on a subsidised basis. The services offered reflect five key business areas such as financing, training, technical assistance, trade assistance, business re-engineering, project management and export promotion. In the case of the BDC its services target six sectors: food and beverage, metal processing, leisure marine, including yachting, information and communication technology/electronics, printing and packaging and entertainment. These said sectors are identified by the government, on the basis of a study which was done by TIDCO, for the promotion of a cluster development strategy. In the case of NEDCO it targets the following sectors: art and craft, food and beverages, fashion and fashion accessories, culture and ecotourism, bed and breakfast operations, indigenous entertainment and light manufacturing.

Avaliação quantitativa da dinâmica espaço-temporal da precipitação na região hidrográfica Tocantins-Araguaia

A análise do comportamento da precipitação em uma bacia hidrográfica é fundamental para a engenharia e gerenciamento dos recursos hídricos. A Região Hidrográfica Tocantins-Araguaia (RHTA) pela sua ocupação recente e potencialidades econômicas, ganha destaque no cenário nacional. Este trabalho avalia quantitativamente a dinâmica espaço-temporal da precipitação anual nesta região durante um período de 30 anos de dados. A dinâmica da precipitação pode ser analisada pelo cálculo da precipitação média em uma dada área, compondo assim mapas de isoietas de precipitação anual. No entanto, a confecção destes mapas requer um método de interpolação que melhor represente as características pluviométricas em locais não amostrados para posterior análise quantitativa do comportamento da precipitação. Para tanto, foram realizados análises exploratórias descritivas amostral e espacial como requisito de estacionaridade do método de interpolação geoestatístico, ajuste e validação do modelo teórico que se adéque ao variograma de precipitação anual. Após a confecção do mapa de isoietas pelo método de Krigagem Ordinária (sem tendência) e Krigagem Universal (com tendência) foi realizado o cálculo do volume precipitado na região hidrográfica pelo método dos contornos. A dinâmica espacial da precipitação foi realizada com base na análise da estatística descritiva, mapa de isoietas, mapa hipsométrico, Índice de Irregularidade Meteorológica (IMM) e Coeficiente de Variação. A dinâmica temporal foi analisada pela distribuição dos totais anuais de precipitação volumétrica para cada sub-bacia da RHTA, pelo Índice de Anomalia Padronizada, na variação interanual de precipitação e teste de tendência e magnitude representados respectivamente pelo Teste de Mann Kendall e Sen’s. Os resultados correlacionados com as anomalias meteorológicas do Oceano Atlântico (Dipolo) e Pacífico (ENOS) indicam o comportamento da precipitação bastante heterogêneo e com grande variabilidade temporal principalmente na sub-bacia Tocantins-Alto (TOA) (14%). Diminuição da amplitude pluviométrica, em anos de anomalia meteorológica intensa ocasionando um incremento de precipitação ao sul das sub-bacias TOA e ARA e diminuição da precipitação na sub-bacia TOB, em eventos de El Niño. Não se pode comprovar pelo teste de Mann Kendall que há uma tendência estatisticamente significativa no volume precipitado na RHTA, mas o estimador Sen’s dá indícios de queda na precipitação na sub-bacia TOA (-1,24 Km^³/ano) e Araguaia (ARA) (-1,13 Km^³/ano) e aumento da precipitação na sub-bacia do Tocantins Baixo (TOB) (0,53 Km^³/ano) e para a RHTA (-1,5 Km^³/ano). Assim a variabilidade espacial e temporal nas sub-bacias está intimamente relacionada aos eventos de anomalia meteorológica, na qual, a sua ação ocorre de maneira irregular ao longo da área de estudo e pode influenciar as diversas atividades sócio-econômicas na RHTA de acordo com sua magnitude e área de ocorrência.

Ensino de gestão da capacidade e da empresa com o apoio do jogo Mercado Virtual no curso de Mestrado Integrado em Engenharia Industrial e Gestão da UMINHO/Azurém e no Programa de Pós-Graduação em Engenharia de Produção da FEB/Bauru/UNESP

O jogo de empresas Mercado Virtual foi desenvolvido para mediar o processo ensino-aprendizagem na área de tomada decisão e gestão de empresas e tem um banco de dados que armazena as decisões dos alunos. Os dados nele armazenados foram analisados em relação ao balanceamento de capacidade, objetivo de lucro e uso de recursos financeiros da empresa e foram encontradas incoerências entre os conteúdos pertinentes ao modelo e as decisões dos alunos. Elas foram classificadas como lacunas de aprendizado. Com o objetivo de analisar se as mesmas se repetem entre alunos do Programa de Mestrado Engenharia de Produção da UNESP de Bauru e Mestrado Integrado em Engenharia Industrial e Gestão da Uminho de Guimarães, Portugal, foram realizados dois experimentos, um em cada grupo. Para realizá-los utilizou-se o jogo Mercado Virtual e uma planilha de dimensionamento da empresa nos dois locais. A Sala de Estudos, os indicadores e o questionário de pesquisa da opinião foram utilizados somente em Portugal. Os resultados mostraram que o jogo é capaz de evidenciar as diferenças de domínio de conteúdo nos dois grupos e, também, que estas diferenças estão associadas aos projetos dos cursos. Sendo uma pesquisa exploratória, os experimentos foram realizados considerando-se somente os controles do jogo. Por isso, propõe-se a realização de pesquisas adicionais combinando controle sobre algumas das variáveis relacionadas do uso do jogo e atuação sobre aprendizagem dos alunos na forma de entrevistas e pesquisas não estruturadas. Conforme previsto, a pesquisa mostrou que os jogos podem ser utilizados com objetivos de aprendizagem mais amplos, considerando-se a avaliação indireta e cruzada sobre as decisões tomadas pelos alunos, como é o caso dos indicadores. Outra contribuição importante da pesquisa refere-se ao uso de jogos de empresas sob condições pouco controladas, ou seja, não houve...

Estudo do fenômeno de instabilidade de estruturas cilíndricas de paredes finas submetidas ao carregamento de pressão externa

Thin walled cylindrical shells are widely used in many areas of industry, including civil, mechanical, nuclear, marine, petroleum and aerospace engineering. The wide application of thin cylindrical shells and the importance of instability phenomenon are the motivation basis to this study, since these factors have a great importance in engineering projects. It is presented a detailed study about the instability of cylindrical shells based on theoretical calculation, which results are compared with finite elements method calculation. The loading and boundary conditions analyzed are based on the most common types verified in real engineering projects and refer respectively to lateral (external) pressure and cylinders with simply supported edges. The calculation based on the finite elements method was executed with ANSYS 13.0 software. The results obtained with this calculation are in good agreement with the analytical theory presented in the technical note NACA No 1341 (BATDORF, 1947) considering a wide range of applicability. On the other hand, the analytical method presented in the book Theory of Elastic Stability (TIMOSHENKO; GERE, 1936) has a very restrict applicability and has presented considerable deviations in a great sort of the analyzed cases

Estudo da propagação de trinca por fadiga sob carregamento de amplitude variável

For engineering projects that require high reliability levels, is often not enough know only physical and chemical material properties. It’s necessary understand the failure mode of these materials in operation to ensure security level in the project and establish more stringent criteria in the analysis of structural integrity. Due to this need, aircraft industry has been using aluminum alloys in their designs and projects. “Currently more than 70% of aircraft structures are built of high strength aluminum alloys among which stand out 7075-T6 and 2024-T3 alloys, which are considered basics for being used in the new alloys development.” (PASTOUKHOV & VOORWALD, 1995). Some years ago ALCOA develops Al 2524 alloy that has emerged as refinement of Al 2024 (Al, Cu. Mg) alloy, with purpose of improve fracture toughness and fatigue resistance on structural components. The present research addresses testing of fatigue crack propagation under variable amplitude loading for Al 2024 alloy, observing the interaction effects from application of overhead blocks and plastic zone at the crack tip and makes an analysis of fracture surface images

Mapeamento geológico-geontécnico de trecho da estrada vicinal na Serra de Itaqueri, Charqueada (SP)

Geological-geotechnical problems affecting escarps as well as embankment and fill slopes of roads and motorways may generate different types of unsteadiness, which are mainly arisen from the deficient knowledge about the physical environment. This results in unsuitable engineering projects and inadequate executions, which can be worsened by an occasional inappropriate maintenance of the construction. A geologically-geotechnically characterization of escarps and slopes is crucial in order to prevent these problems. This work deals with a geological-geotechnical study of 1:10.000 scale mapping in a stretch of a local road (CHQ-40) at the Serra de Itaqueri, Charqueada town, State of São Paulo. The stretch is known by several physical problems as erosion and mass movement. The methods of study were based on an integrative analysis of the diverse elements of the physical environment by using aerial photographs - to obtain the physiographic compartmentalization of terrain units - as well as field work - to accomplish the evaluation of the units by employing sketch lists. To achieve this, we selected several techniques in order to identify and classify different types of existing problems as erosion, landslide in embankments and fill slopes, rockfall, block rolling, among others. We also included the analysis of soil horizon, thickness and composition. The geological-geotechnical mapping resulted in six units: 1- Sandstones in cuesta’s backhill; 2 – Basalts in cuesta’s front; 3- Sandstones in cuesta’s front; 4 – Talus and colluvial deposits at cuesta’s foothill; 5- Sandstones of the Piramboia Formation in hillside; and 6 – Colluvial soil in the hill top. A characterization of the geological-geotechnical units is detailed, coupled to the cartographic material. Other cartographic products elaborated for this study included 1:10.000 maps of hypsometry, slope and curvature

Estudo, desenvolvimento e concepção de uma célula de carga

In engineering projects, it’s fundamental to determine the active loads in components in order to guarantee acceptable values of safety and reliability according to project specifications. On the other hand, force measurement methods might be very complex and impracticable in some cases and, so that, load cells with eletric resistance strain gages can be applied as a simple and accurate option to measure the required load. The main purpose of this paper is to present the development of a load cell that measures uniaxial forces using electric resistance strain gages without being influenced by the location of the loading in a cantilever beam. For that, it was taken as basis a secondary purpose which is to present a general study of basic and wide concepts about transducers, load cells and extensometers primarily. Information such as: loading and measurements types, characteristics of the presented devices as well as factors that influence its functioning, the most common kinds of Wheatstone bridge links, the main points of a load cell project, cements used to fix extensometers and, finally, the project itself with the tests of the built transducer are presented. By the end of this paper, all the results are shown and analyzed, concluding about the designed load cell and the work itself

Medições de áreas por fotografias aéreas, em escala nominal, comparadas com a área obtida em fotografias com escalas corrigidas por meio de um SIG

Land use management has becoming a very important activity. Aerial photo interpretation is a basic resource and constitutes in a technique which enables infinite refining. Agricultural development and land use require a careful initial planning in order not only to protect them against superficial changing provoked by natural phenomenon but also to gradually develop its productive capacity. For the efficiency of land management, it is necessary to access correct and detailed information which can be available through aerial images of remote sensing. The use of vertical aerial photography through Remote Sensing has become more common in boundary survey projects, management and exploration, mainly because it substitutes, with lots of advantage, for cartographic bases, besides offering detailed characteristics, eliminating access difficulties in inaccessible areas, as well as facilitating a tridimensional view once it increases map efficiency and accuracy by combining field and laboratory work with photography interpretation. This work, using panchromatic aerial photography in nominal scale 1:25000 (1962), 1:45000 (1977) , and approximate nominal scale of 1:30.000, originating from aerial survey obtained in 2005, aimed at showing through the Geographic Information System (GIS) the possibility of developing a more complete and accurate analysis of the area values, obtained directly from photos without scale correction, and after comparing it with area values obtained from aerial photography with correct scale referred in IGC (Brazilian Cartography and Geography Institute) guidelines, resulting in an error coefficient which shows area differences through two proposed study. Considering the aerial photography in three different years: 1962, 1977 and 2005 it is possible to affirm that the 2005’s images presented lower values of area difference (43, 48 square meters) than determined area values in reference chart and the 2005’s colored images has facilitated the photo interpretation of the landscape, becoming accurate the confronting traces and among land owners and consequently offering precision during land marking.

Application of Submerged Grouted Anchors in Sheet Pile Quay Walls

Sheet pile walls are one of the oldest earth retention systems utilized in civil engineering projects. They are used for various purposes; such as excavation support system, cofferdams, cut-off walls under dams, slope stabilization, waterfront structures, and flood walls. Sheet pile walls are one of the most common types of quay walls used in port construction. The worldwide increases in utilization of large ships for transportation have created an urgent need of deepening the seabed within port areas and consequently the rehabilitation of its wharfs. Several methods can be used to increase the load-carrying capacity of sheet-piling walls. The use of additional anchored tie rods grouted into the backfill soil and arranged along the exposed wall height is one of the most practical and appropriate solutions adopted for stabilization and rehabilitation of the existing quay wall. The Ravenna Port Authority initiated a project to deepen the harbor bottom at selected wharves. An extensive parametric study through the finite element program, PLAXIS 2D, version 2012 was carried out to investigate the enhancement of using submerged grouted anchors technique on the load response of sheet-piling quay wall. The influence of grout-ties area, length of grouted body, anchor inclination and anchor location were considered and evaluated due to the effect of different system parameters. Also a comparative study was conducted by Plaxis 2D and 3D program to investigate the behavior of these sheet pile quay walls in terms of horizontal displacements induced along the sheet pile wall and ground surface settlements as well as the anchor force and calculated factor of safety. Finally, a comprehensive study was carried out by using different constitutive models to simulate the mechanical behavior of the soil to investigate the effect of these two models (Mohr-Coulomb and Hardening Soil) on the behavior of these sheet pile quay walls.

Equations for the Drag Force and Aerodynamic Roughness Length of Urban Areas with Random Building Heights

We use a conceptual model to investigate how randomly varying building heights within a city affect the atmospheric drag forces and the aerodynamic roughness length of the city. The model is based on the assumptions regarding wake spreading and mutual sheltering effects proposed by Raupach (Boundary-Layer Meteorol 60:375-395, 1992). It is applied both to canopies having uniform building heights and to those having the same building density and mean height, but with variability about the mean. For each simulated urban area, a correction is determined, due to height variability, to the shear stress predicted for the uniform building height case. It is found that u (*)/u (*R) , where u (*) is the friction velocity and u (*R) is the friction velocity from the uniform building height case, is expressed well as an algebraic function of lambda and sigma (h) /h (m) , where lambda is the frontal area index, sigma (h) is the standard deviation of the building height, and h (m) is the mean building height. The simulations also resulted in a simple algebraic relation for z (0)/z (0R) as a function of lambda and sigma (h) /h (m) , where z (0) is the aerodynamic roughness length and z (0R) is z (0) found from the original Raupach formulation for a uniform canopy. Model results are in keeping with those of several previous studies.