Monize Sâmara Visentini

Review of real-time vehicle schedule recovery methods in transportation services

This paper presents a comprehensive review on methods for real-time schedule recovery in transportation services. The survey concentrates on published research on recovery of planned schedules in the occurrence of one or several severe disruptions such as vehicle breakdowns, accidents, and delays. Only vehicle assignment and rescheduling are reviewed; crew scheduling and passenger logistics problems during disruptions are not. Real-time vehicle schedule recovery problems (RTVSRP) are classified into three classes: vehicle rescheduling, for road-based services, train-based rescheduling, and airline schedule recovery problems. For each class, a classification of the models is presented based on problem formulations and solution strategies. The paper concludes that RTVSRP is a challenging problem that requires quick and good quality solutions to very difficult and complex situations, involving several different contexts, restrictions, and objectives. The paper also identifies research gaps to be investigated in the future, stimulating research in this area.

A vision of Orkut's users: studying this phenomenon through cognitive absorption

This study aims to identify the influence that Cognitive Absorption has on the intention of using Orkut. It happens due to the fact that Cognitive Absorption is related to the state of deep involvement users carry with an individual task, performed with the support of Information Technology (IT); it corroborates the study on this virtual community. Therefore, through descriptive research with a quantitative character and with the aid of structural equations, 645 Orkut users were investigated. After the identification of suitability of all indexes tested and fit for both constructs and the final model. The conclusion drawn is that Cognitive Absorption explains the 41% intention of using Orkut, emphasizing that for this kind of IT the Cognitive Absorption seems perfectly adequate to measure the Intention of Use.

Modelagem do projeto da cadeia de suprimentos global: considerações teóricas e perspectivas futuras

This theoretical paper aims to present and discuss features of mathematical optimization models for the global supply chain design in order to support future researches on this contemporary theme. The bibliographic research was performed in major international journals of Operational Research, comprising predominantly papers published between 2000 and 2013. Of the 111 papers selected, 22 were analyzed in depth considering aspects related to the modeling the global supply chain and international factors addressed. Through theoretical discussion, we identified emerging issues, indicating opportunities and needs for development of new mathematical models and solution techniques.

ANALISANDO AS RELAÇÕES NA CADEIA DE SUPRIMENTOS ATRAVÉS DA TEORIA DOS CUSTOS DE TRANSAÇÃO

A Teoria dos Custos de Transacao (TCT) pode contribuir na explicacao do funcionamento e das relacoes da Cadeia de Suprimentos. Tendo em vista os aspectos convergentes dessas duas abordagens, este ensaio teorico objetiva compreender como a racionalidade limitada, o oportunismo e a relacao interfirmas, aspectos presentes na TCT, podem influenciar na gestao da cadeia de suprimentos. Alguns indicios demonstram que tanto a racionalidade limitada quanto o oportunismo aumentam conforme se tem um acrescimo de complexidade e incerteza na transacao. O compartilhamento da informacao atua como fator fundamental na reducao desses inconvenientes, contribuindo para que se consiga melhorar a relacao interfirmas e minimizar os custos de transacao. Tambem sao evidenciados os aspectos que podem trazer vantagem competitiva as empresas participantes de uma cadeia de suprimentos, dentre eles, a adocao correta da estrategia de governanca. Palavras-chave: Teoria dos Custos de Transacao; Cadeia de Suprimentos; Racionalidade Limitada; Oportunismo; Relacao Interfirmas. ABSTRACT

Resolução integrada de problemas do planejamento do transporte público: foco na tabela de horários e no escalonamento de veículos com frota heterogênea

In this paper, we propose a new Integer Linear Programming model, based on a time-space network that integrates the timetable generation problem and the vehicle scheduling problem with heterogeneous fleet. A difference of this approach consists in considering the demand for the timetable redefinition and the vehicle scheduling, factor rarely applied in optimization models of the transportation system. We applied real and large random instances. The results indicate that the model may contribute to optimizing the public transport planning leading to significant savings in terms of scheduled vehicles. Moreover, as the timetable changes are fairly short, it is slightly modified, minimally modifying the passengers routine, which enables the application of these approaches to real context.

A INFLUÊNCIA DOS DETERMINANTES DO TRABALHO GERENCIAL NA PERCEPÇÃO DO AJUSTE ENTRE A TECNOLOGIA E A TAREFA: UM ESTUDO EXPLORATÓRIO (doi:10.5329/RESI.2010.0902003)

This paper investigates if the managerial work nature modifies the managers perception regarding the adjustment of Information Technology (IT) to their task. The indicators of managerial work, as experience and frequency of IT use and manager decision-making roles, were based on studies of Vlahos and Ferrat (1998) and Vlahos, Ferratt and Knoepfle (2004) as well as the task technology fit, reasoned from the Task-Technology Fit model (TTF) (Goodhue, 1995). This paper contributes to understanding the IS as a support tool for the tasks that composed the managers role in the organization. Through an exploratory study conducted with 238 managers, we observed that more increases the experience of the individual with the Information System (IS), greater the adjustment perceived for it, between the technology and the task running; and higher the user access the IS, greater the fit between the technology and their tasks. As for the decision-making roles, we identified the roles of manager/ entrepreneur and conflict manager are those who envisage a better adaptation of technology to their work, getting through the IS support for the work to proceed more efficiently.