Ramos, Tania Rodrigues Pereira, Maria Isabel Gomes, and Ana Paula Barbosa-póvoa. "
Restructuring service areas and vehicle routes in a recyclable waste collection system."
EurOMA Conference. Cambridge, UK 2011. 1-10.
AbstractThe present work aims to develop a decision supporting tool to help the decision making process related to the planning of waste collection systems. Such systems involve more than one depot and the objective is to define the delimitation of service areas and the vehicles routes. The problem is modelled as a multi-product, multi-depot vehicle routing problem. A hybrid method that combines exact formulations with heuristic procedures is developed and applied to a real recyclable collection system whose managers want to restructure the current service areas as well as the vehicle routes used to collect three types of recyclable materials.
Azevedo, S. G., and H. Carvalho. "
RFID Technology in the Fashion Supply Chain: An Exploratory Analysis."
Fashion Supply Chain Management: Industry and Business Analysis. Business Science Reference (an imprint of IGI Global), 2011. 302-326.
AbstractRadio Frequency Identification (RFID) is a new technology that has received considerable attention from academics and practitioners due to its large scope of application, advantages and potentialities. This chapter aims to highlight the potentialities associated with RFID in fast moving Fashion Supply Chain Management (FSCM). The research emphasizes the technological contribution to the Fashion Supply Chain (FSC) such as speed up logistics activities, increased quality, reduced prices, and more responsive improvements for customer satisfaction. The chapter reviews the RFID technology, presents the benefits, disadvantages, and barriers associated with it. To explore the deployment of the RFID technology in the Fashion Supply Chain (FSC), a case study investigation of companies in different FSCM nodes was carried out. A cross-case analysis it is also presented to achieve a deeper understanding about this technology in a fast moving FSCM context
Karlovich, Alexei Yu. "
Singular integral operators on Nakano spaces with weights having finite sets of discontinuities."
Function spaces IX. Proceedings of the 9th international conference, Kraków, Poland, July 6–11, 2009. Banach Center Publications, 92. Eds. Henryk Hudzik, Grzegorz Lewicki, Julian Musielak, Marian Nowak, and Leszek Skrzypczak. Warszawa: Polish Academy of Sciences, Institute of Mathematics, 2011. 143-166.
AbstractIn 1968, Gohberg and Krupnik found a Fredholm criterion for singular integral operators of the form \(aP+bQ\), where \(a,b\) are piecewise continuous functions and \(P,Q\) are complementary projections associated to the Cauchy singular integral operator, acting on Lebesgue spaces over Lyapunov curves. We extend this result to the case of Nakano spaces (also known as variable Lebesgue spaces) with certain weights having finite sets of discontinuities on arbitrary Carleson curves.
Ramos, Tania Rodrigues Pereira, Maria Isabel Gomes, and Ana Paula Barbosa-póvoa Solving a multi-product, multi-depot vehicle routing problem by a hybrid method. Livro de actas do 15º congresso da APDIO, IO2011. Coimbra, Portugal, 2011.
AbstractThis paper is focused on the delimitation of service areas and on vehicle routes definition in recyclable waste collection systems with more than one depot. Three types of materials have to be collected in separated routes, so the problem is modelled as a multi-product, multi-depot vehicle routing problem. A hybrid method is developed where a MIP solver is embedded inside a heuristic framework. The effectiveness of this method is tested by comparing the results obtained for some test instances when solved only by an exact formulation. The hybrid method is then applied to a medium size problem based on a real recyclable waste collection system.
Hollander, Yoav, Alan Hu, João M. Lourenço, and Ronny Morad. "
Special Session on Debugging."
Hardware and Software: Verification and Testing. Eds. Sharon Barner, Ian Harris, Daniel Kroening, and Orna Raz. Vol. 6504. Lecture Notes in Computer Science, 6504. Springer Berlin / Heidelberg, 2011. 24-28.
AbstractIn software, hardware, and embedded system domains, debugging is the process of locating and correcting faults in a system. Depending on the context, the various characteristics of debugging induce different challenges and solutions. Post-silicon hardware debugging, for example, needs to address issues such as limited visibility and controllability, while debugging software entails other issues, such as the handling of distributed or non-deterministic computation. The challenges that accompany such issues are the focus of many current research efforts. Solutions for debugging range from interactive tools to highly analytic techniques. We have seen great advances in debugging technologies in recent years, but bugs continue to occur, and debugging still encompasses significant portions of the life-cycles of many systems. The session covered state-of-the-art approaches as well as promising new research directions in both the hardware and software domains.
Barbosa, R., N. Lapa, H. Lopes, I. Gulyurtlu, and B. Mendes. "
Stabilization/solidification of fly ashes and concrete production from bottom and circulating ashes produced in a power plant working under mono and co-combustion conditions."
Waste Management. 31.9-10 (2011): 2009-2019.
AbstractTwo combustion tests were performed in a fluidized bed combustor of a thermo-electric power plant: (1) combustion of coal; (2) co-combustion of coal (68.7% w/w), sewage sludge (9.2% w/w) and meat and bone meal (MBM) (22.1% w/w).
Three samples of ashes (bottom, circulating and fly ashes) were collected in each combustion test. The ashes were submitted to the following assays: (a) evaluation of the leaching behaviour; (b) stabilization/solidification of fly ashes and evaluation of the leaching behaviour of the stabilized/solidified (s/s) materials; (c) production of concrete from bottom and circulating ashes. The eluates of all materials were submitted to chemical and ecotoxicological characterizations. The crude ashes have shown similar chemical and ecotoxicological properties. The s/s materials have presented compressive strengths between 25 and 40 MPa, low emission levels of metals through leaching and were classified as non-hazardous materials. The formulations of concrete have presented compressive strengths between 12 and 24 MPa. According to the Dutch Building Materials Decree, some concrete formulations can be used in both scenarios of limited moistening and without insulation, and with permanent moistening and with insulation.
Dias, Ricardo J., Dino Distefano, João M. Lourenço, and João Costa Seco StarTM: Automatic Verification of Snapshot Isolation in Transactional Memory Java Programs. Departamento de Informática FCT/UNL, 2011.
AbstractThis paper presents StarTM , an automatic verification tool for transactional memory Java programs executing under relaxed isolation levels. We certify which transactions in a program are safe to execute under Snapshot Isolation without triggering the write-skew anomaly, opening the way to run-time optimizations that may lead to considerable performance enhancements.
Our tool builds on a novel shape analysis technique based on Separation Logic to statically approximate the read- and write-sets of a transactional memory Java program. This technique is particularly challenging due to the presence of dynamically allocated memory.
We implement our technique and apply our tool to a set of intricate examples. We corroborate known results, certifying some of the examples for safe execution under Snapshot Isolation by proving the absence of write-skew anomalies. In other cases we identify transactions that potentially trigger the write-skew anomaly.
Luís, João E., João M. Lourenço, and Paulo A. Lopes. "
Suporte Transaccional para o Sistema de Ficheiros Btrfs."
InForum 2011: Proceedings of InForum Simpósio de Informática. Coimbra: Universidade do Coimbra, 2011.
AbstractEm caso de falha abrupta de um sistema, é imperativo garantir a consistência do Sistema de Ficheiros (SF). Actualmente existem várias soluções que visam garantir que tanto os dados como os metadados do SF se encontram num estado consistente, mas que não contemplam a garantia de consistência dos dados do ponto de vista das aplicações. Por exemplo, aplicações que pretendam alterar vários ficheiros de configuração terão de encontrar mecanismos para garantir que, ou todos os ficheiros são devidamente alterados, ou nenhum o é, evitando assim que numa situação de falha o conteúdo dos ficheiros fique inconsistente. Do ponto de vista da aplicação, pode não ser simples implementar este comportamento sobre um SF típico; e pode também não ser razoável utilizar um Sistema de Gestão de Bases de Dados (SGBD), que oferece propriedades ACID. Neste artigo propomos, testamos e avaliamos uma integração das propriedades ACID num SF. Partindo do suporte para snapshots do sistema de ficheiros Btrfs, oferece-se uma semântica transaccional às aplicações que operam sobre volumes (sub-árvores) do SF, sem comprometer a semântica POSIX do SF.