15 documents found, page 1 of 2
Aplicação de indução eletromagnética e modelação inversa para o mapeamento 3D d...
Farzamian, M.; Paz, A.; Castanheira, N.; Ramos, T.; Martinez Moreno, F.; Rodríguez, M.; Monteiro Santos, F.; Alexandre, C.; Vanderlinden, K.Neste estudo, foi feito um ensaio num campo agrícola inserido no perímetro de rega do Roxo, no Alentejo, usando o sensor de indução eletromagnética DUALEM21, de forma a analisar o seu potencial no mapeamento 3D da textura do solo. Os dados da condutividade elétrica aparente do solo (ECa), obtidos com o sensor, foram transformados utilizando um algoritmo de modelação inversa, Quasi-3D, para obter imagens da cond...
Interacção da salinidade e da fertilização azotada na produtividade do milho-grão
Gonçalves, M.C.; Martins, J. C.; Castanheira, N.; Santos, F. L.; Neves, M. J.; Reis, J.; Prazeres, A.; Ramos, T.; Fonte, S.; Pires, F.; Bica, M.Instalaram-se, em 2004 e 2005, dois ensaios de campo (Évora e Alvalade), em solos diferentes, com mobilização convencional e a cultura de milho-grão regada com sistema gota-a-gota, em fonte tripla linear. Neste sistema existem 3 fontes: água salina, água de rega e solução fertilizante, de modo a obter dois gradientes, um de salinidade (adição de NaCl), e outro de fertilizante (adição de solução azotada). Preten...
Optimization of a recyclabe waste collection system: The Valorsul case study
Lopes, D.; Ramos, T.; Póvoa, A.This paper studies alternative scenarios for a recyclable waste collection system in order to increase efficiency in their operations. Three alternative scenarios are proposed where two different locations for one or two additional depots are studied. The problem is considered as a multi-depot vehicle routing problem and a solution approach is developed. The three scenarios are compared with the current solutio...
Planning collection routes with multi-compartment vehicles
Oliveira, A.; Ramos, T.; Martins, A.This paper aims to assess the impact of using vehicles with multiple compartments in a recyclable waste collection system. Such systems perform single-material routes to collect three types of recyclable materials (paper, glass and plastic/metal), where vehicles with a single compartment are used. If vehicles with multi-compartments were used, two or even the three materials could be collected simultaneously wi...
Assessing obstetrics perceived service quality at a public hospital
Martins, A.; Crespo de Carvalho, J.; Ramos, T.; Fael, J.Assessing service quality has become a major issue in the healthcare sector. Although direct evaluation has already taken place, literature is scarce in terms of the impact the distance covered by the user has on perceived service quality. The aim of this study was to assess the influence distance has on perceived service quality when no similar service alternatives are available. The Servperf instrument was us...
Economic and environmental concerns in planning recyclable waste collection sys...
Ramos, T.; Gomes, M. I.; Barbosa-Póvoa, A. P.This paper addresses the planning of recyclable waste collection systems while accounting for economic and environmental concerns. Service areas and vehicle routes are defined for multiple-depot logistics networks where different products have to be collected. The problem is modeled as a multi-product, multi-depot vehicle routing problem with two objective functions: distance and CO2 emissions minimization. A d...
Planning a sustainable reverse logistics system: balancing costs with environme...
Ramos, T.; Gomes, M. I.; Barbosa-Póvoa, A. P.The present work aims to support tactical and operational planning decisions of reverse logistics systems while considering economical, environmental and social objectives. In the literature, when addressing such systems economical aspects have been often used, while environmental concerns have been only recently emerging. The social component is the one less studied, and rarely the combination of the three con...
Assessing obstetrics perceived service quality at a public hospital
Martins, A.; Crespo de Carvalho, J.; Ramos, T.Assessing service quality has become a major issue in the healthcare sector. Although direct evaluation has already taken place, literature is scarce in terms of the impact the distance covered by the user has on perceived service quality. The aim of this study was to assess the influence distance has on perceived service quality when no similar service alternatives are available. The Servperf instrument was us...
Strategic fast supply demand-chains in a network context: opportunistic practic...
Crespo de Carvalho, J.; Martins, A.; Ramos, T.; Dias, E. B.This paper has a conceptual character and explores an approach between transaction cost analysis theory and network theory when applied to supply chains in a broader context: industrial management research. This approach raises the assumptions that fast supply chains, i.e., supply chains made of short time relationships and multiple partners can contribute to destroying trust and collaboration between companies...
Assessing and improving management practices when planning packaging waste coll...
Ramos, T.; Gomes, M. I.; Barbosa-Póvoa, A. P.Packaging waste collection systems are responsible to collect, within a geographic area, three types of packaging materials (paper, glass and plastic/metal) that are disposed by the final consumer into special bins. Those systems are often characterized by having a network with multiple depots that act as transfer and sorting stations, and where the vehicle fleet is based. However, each depot is often managed i...