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Publications

2019

Computational Simulation Results in Power Systems Operation to Integrate Reliability in the Security Constrained Optimization Problem

Authors
Sheikh, M; Aghaei, J; Nikoobakht, A; Osório, GJ; khah, MS; Lotfi, M; Catalão, JPS;

Publication
Conference on Next Generation Computing Applications, NextComp 2019, Mauritius, September 19-21, 2019

Abstract
In order to decrease operation costs in a security constrained unit commitment (SCUC) problem, strategies such as transmission switching (TS) can be utilized. However, having no limit for the switching of circuit breakers (CBs) in the system is troublesome, since a high number of switching increases the failure probability and decreases the reliability of a CB, in addition to resulting in shorter CB lifespans and higher maintenance and operating costs. In this paper, the reliability of CBs is integrated into the SCUC problem with TS to limit its switching. Since the higher reliability of CBs will increase the reliability of the system, it can be inferred that the reliability of CBs will affect the amount of load shedding. A linearization method is presented to linearize the CB reliability equation. Also, an improved linear AC optimal power flow (ILACOPF) with dynamic thermal line rating (DTLR) which considers weather conditions is used in the model to further reduce the number of switching. In order to evaluate the suggested approach, numerical testing is performed for 6-bus and large-scale 118-bus IEEE test systems with different scenarios. © 2019 IEEE.

2019

Design of an underwater sensor network perpetually powered from AUVs

Authors
Pessoa L.M.; Duarte C.; Salgado H.M.; Correia V.; Ferreira B.; Cruz N.A.; Matos A.;

Publication
OCEANS 2019 - Marseille, OCEANS Marseille 2019

Abstract
In this paper we evaluate the long-term deployment feasibility of a large-scale network of abandoned underwater sensors, where power is provided by autonomous underwater vehicles (AUVs) in periodic visits.

2019

Comparison of Financial Performance Between Branded and Non-Branded Hotel Companies Using Composite Indicator

Authors
Martins, CA; Vaz, CB; Alves, JMA;

Publication
VISION 2025: EDUCATION EXCELLENCE AND MANAGEMENT OF INNOVATIONS THROUGH SUSTAINABLE ECONOMIC COMPETITIVE ADVANTAGE

Abstract
The Hospitality industry is one of the main sectors of tourism activity, being important to assess the performance of the hotel companies. The aim of the present paper is to study the financial performance of 570 companies operating hotel units in Portugal, in 2017, allowing for comparison among companies with similar stars rating and market orientation to explore the question of branded and non-branded affiliation. This issue is studied using a methodology based on Data Envelopment Analysis to assess the overall performance for each company. The hotel company performance is assessed through the aggregation of multiple financial indicators using the composite indicator derived from the DEA model. The empirical results show that the hotel branded companies have, on average, significantly, higher overall financial performance than hotel non-branded companies. Although, the best practices are observed in hotel branded and non-branded companies. This analysis can support the strategic decision process of the hotel companies in choosing to operate independently or selecting a brand affiliation.

2019

Does Theory Really Fit Real Life Situations?

Authors
Furtado, JV; Pereira, AR; Pereira, I; Moreira, AC;

Publication
Handbook of Research on Entrepreneurship, Innovation, and Internationalization - Advances in Business Strategy and Competitive Advantage

Abstract
This chapter analyzes the strategic international formulation of a SME technological service-based firm to perceive the internationalization theory that best suits the company throughout its history. The literature review of the most studied internationalization patterns—Uppsala Model, Born Globals, Born Again Globals, and Born Regionals—allowed comparison of the main characteristics of each theory vis-à-vis the firm's internationalization. A synthesis table summarizes the main characteristics of the internationalization process of each model and presents a clearer view of the particularities of each. Analysis of the primary data and interviews provided by the company's CEO made it possible to compare the internationalization process adopted by the company with those characteristics, facilitating the process of identifying the strategy followed. The present case study took into account the theoretical model with the greatest similarity of characteristics with the path followed by the firm, as well as its learning and future plans.

2019

História, escolas e movimentos dos indicadores culturais

Authors
Martins, TC; Gomes de Azevedo Pinto, MM;

Publication
Políticas Culturais em Revista

Abstract
A literatura dos indicadores culturais  reconhece-os como o membro mais novo da família dos indicadores. Na perspectiva de entender como ocorre a sua conceituação e aplicação na realidade social, procura-se compreender  a sua história à luz das escolas e movimentos em torno do tema. Para tanto, problematiza-se esse percurso a partir de agentes, instituições, temporalidades e intencionalidades na definição e uso dos indicadores. Conclui-se com a apresentação dos resultados da pesquisa exploratória realizada, envolvendo o levantamento bibliográfico e documental,  nomeadamente um <em>framework</em> das linhas de atuação e os expoentes de investigação e uso dos indicadores culturais.

2019

Novel Incentive Mechanism for End-Users Enrolled in DLC-Based Demand Response Programs Within Stochastic Planning Context

Authors
Erdinc, O; Tascikaraoglu, A; Paterakis, NG; Catalao, JPS;

Publication
IEEE TRANSACTIONS ON INDUSTRIAL ELECTRONICS

Abstract
In this paper, a novel direct load control (DLC) planning based on providing free energy credits to residential end-users for their heating, ventilation, and air conditioning load during demand response (DR) events is proposed. The obtained credit can then be used by the end-users during relatively higher price periods free-of-cost to enable them lowering their energy procurement costs. Furthermore, the resulting reduction in the total household energy consumption considerably decreases the critical load demands in power systems, which is of vital importance for load-serving entities in maintaining the balance between supply and demand during peak load periods. In this regard, the aforementioned energy credits-based incentive mechanism is proposed for end-users enrolled in the DLC-based DR program, as a new contribution to the existing literature, testing it in a stochastic day-ahead planning context.

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