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Publications

Publications by SYSTEM

2018

Navigating in a sea of project supporting apps: how to get acceptance for managerial needs

Authors
Costa, JS; Soares, AL;

Publication
CENTERIS 2018 - INTERNATIONAL CONFERENCE ON ENTERPRISE INFORMATION SYSTEMS / PROJMAN 2018 - INTERNATIONAL CONFERENCE ON PROJECT MANAGEMENT / HCIST 2018 - INTERNATIONAL CONFERENCE ON HEALTH AND SOCIAL CARE INFORMATION SYSTEMS AND TECHNOLOGIES, CENTERI

Abstract
Organizations are nowadays more and more structured in projects in the so-called project-based organizations (PBO). The advantages of PBOs - operational and managerial focus and effectiveness - are counterweight by difficulties in information / knowledge sharing and overall coordination. Project management (PM) applications have been adopted by PBOs with success, mostly at the project level. More innovation-oriented PBOs are keen to experiment and adopt a range of different project supporting applications to optimize several aspects of project management, resulting in “ecosystems” of PM related applications. This paper addresses the problems arising from the implementation of a global project coordination and collaboration application in a research center whose ecosystem of PM applications is extensive. The main challenge has been managing change. An action-research approach was followed to successfully implement the new application while reflecting theoretically on the process and results. The main conclusion is that the requirements elicitation and negotiation are as important as the management of change regarding processes and individual practices. © 2018 The Authors. Published by Elsevier Ltd..

2018

Decision Support Tool for Dynamic Scheduling

Authors
Ferreirinha, L; Santos, AS; Madureira, AM; Varela, MLR; Bastos, JA;

Publication
Hybrid Intelligent Systems - 18th International Conference on Hybrid Intelligent Systems, HIS 2018, Porto, Portugal, December 13-15, 2018

Abstract
Production scheduling in the presence of real-time events is of great importance for the successful implementation of real-world scheduling systems. Most manufacturing systems operate in dynamic environments vulnerable to various stochastic real-time events which continuously forces reconsideration and revision of pre-established schedules. In an uncertain environment, efficient ways to adapt current solutions to unexpected events, are preferable to solutions that soon become obsolete. This reality motivated us to develop a tool that attempts to start filling the gap between scheduling theory and practice. The developed prototype is connected to the MRP software and uses meta heuristics to generate a predictive schedule. Then, whenever disruptions happen, like arrival of new tasks or cancelation of others, the tool starts rescheduling through a dynamic-event module that combines dispatching rules that best fit the performance measures pre-classified by Kano’s model. The proposed tool was tested in an in-depth computational study with dynamic task releases and stochastic execution time. The results demonstrate the effectiveness of the model. © 2020, Springer Nature Switzerland AG.

2018

Understanding Customer-Focused Supply Chain Management: A Set-Based Concept Framework

Authors
João Augusto de Sousa Bastos;

Publication

Abstract

2018

Observability of power systems with optimal PMU placement

Authors
Carvalho, M; Klimentova, X; Viana, A;

Publication
COMPUTERS & OPERATIONS RESEARCH

Abstract
Phasor Measurement Units (PMUs) are measuring devices that, when placed in electrical networks, observe their state by providing information on the currents in their branches (transmission lines) and voltages in their buses. Compared to other devices, PMUs have the capability of observing other nodes besides the ones they are placed on. Due to a set of observability rules, depending on the placement decisions, the same number of PMUs can monitor a higher or smaller percentage of a network. This leads to the optimization problem hereby addressed, the PMU Placement Problem (PPP) which aims at determining the minimum number and location of PMUs that guarantee full observability of a network at minimum cost. In this paper we propose two general mathematical programming models for the PPP: a single-level and a bilevel integer programming model. To strengthen both formulations, we derive new valid inequalities and promote variable fixing. Furthermore, to tackle the bilevel model, we devise a cutting plane algorithm amended with particular features that improve its efficiency. The efficiency of the algorithm is validated through computational experiments. Results show that this new approach is more efficient than state-of-the-art proposals.

2018

Preface to the Special Issue on Improving Healthcare: New Challenges, New Approaches

Authors
Dias, JM; Rocha, H; Viana, A;

Publication
INTERNATIONAL TRANSACTIONS IN OPERATIONAL RESEARCH

Abstract

2018

Stochastic last-mile delivery with crowdshipping

Authors
Gdowska, K; Viana, A; Pedroso, JP;

Publication
Transportation Research Procedia

Abstract
For the predicted growth of e-commerce, supply chains need to adapt to new conditions, so that delivery can be fast, cheap and reliable. The key to success is the last-mile product delivery (LMD) - the last stage of the supply chain, where the ordered product is delivered to the final consumer's location. One innovative proposal puts foundations in a new delivery model where a professional delivery fleet (PF) is supplemented partially or fully with crowdshipping. The main idea of crowdshipping is to involve ordinary people - in our case in-store shoppers - in the delivery of packages to other customers. In return, occasional couriers (OC) are offered a small compensation. In hitherto formulated problems it was assumed that OCs always accept delivery tasks assigned to them. In this paper we consider OCs as independent agents, which are free to reject assignments. The main contribution of the paper is an original bi-level methodology for matching and routing problem in LMD with OCs and the PF. The goal is to use crowdshipping to reduce the total delivery cost in a same-day last-mile delivery system with respect to occasional couriers' freedom to accept or reject the assigned delivery. We introduce probability to represent each OC's willingness to perform the delivery to a given final customer. We study the OCs' willingness to accept or reject delivery tasks assigned to them and the influence of their decision on the total delivery cost associated to both the OCs' compensation fees and the delivery cost generated by the PF used for the delivery of remaining parcels. © 2018 The Author(s).

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