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- Airports Catchment Area Size Definition: a Portuguese Case StudyPublication . Baltazar, Maria Emilia; Silva, JorgeThe definition of the Catchment Area of an airport is very broad and current literature suggests doing it in combination with certain pre-defined criteria: the assessment of the impact or effectiveness of a certain airport, or from the perspective of competition between airports. This paper aims to assess the validity of the hinterland defined by the Portuguese airport manager, ANA - Aeroportos de Portugal. A case study was developed involving the three main national airports: Lisbon (LIS), Oporto (OPO) and Faro (FAO). ANA defined the hinterland of each airport. Thus, a survey was developed to the companies located within the hinterland of every airport aiming to understand the existence of any relationship between them and the closest airport. We followed a stratified sample method to determine the size of the survey. We only considered import and export companies with the highest business volumes. Data analysis was performed using GIS (Geographic Information System), that is a software, spatial data and computational procedures system that enables and facilitates the analysis, management and representation of space and phenomena that occur in it. We collected a total of 243 surveys. The main conclusion of the study was that the calculation of an airport’s hinterland based exclusively on the travel time or distance is, potentially, misleading. It is proposed the use of other factors. The validity of such a method and practice raises some doubts. The actual distribution of economic activities and population is ignored as well as the mutual influence of several airports. Further research is now needed to calculate airports actual influence.
- Global decision support for airport performance and efficiency assessmentPublication . Baltazar, Maria; Rosa, Tiago; Silva, JorgeAirport benchmarking depends on airport performance and efficiency indicators, and it is an important issue for business, operational management, regulatory agencies, airlines and passengers. Using the MACBETH (Measuring Attractiveness by a Categorical Based Evaluation Technique) approach, a hierarchical additive value model is constructed with criteria weights and value scales derived from expert's judgments (obtained by an online survey) and by comparison of different reference levels and profiles of performance. This model measures airport performance and efficiency and also peer benchmarks it within a set of direct competitors or self-benchmarks itself during a specified period. GDS (Global Decision Support) model outputs, integrated into a management system, allows the identification of deficiencies requiring urgent intervention and corrective measures for its continuous improvement.
- Air Budjet: a VTOL virtual operator company in PortugalPublication . Duarte, Manuel Mendes; Baltazar, Maria Emilia; Silva, J.Creation of sustainable transportation service for a new and virtual airline company that uses VTOL aircraft in order to increase mobility and flexibility in Portugal. This study started with the VTOL concepts, peripherally and accessibility, and business models and plans reviews. The air service characterization was then carried out using localization and trajectory optimization algorithms, thus allowing to elaborate two applications (software): one for clients to book their flights and another that compiles flight's data booked by clients and optimizes flights routes/trajectories. With this study, it is possible to depict the viability of the economic-financial results of the new virtual company and the application development results with the optimized trajectories. The development of this air service will increase accessibility and mobility in all regions of Portugal and companies that cannot afford the costs of executive aviation, too. In order to facilitate the booking of the flights, an application was created for the client in order to optimize the company costs related to this air service, and thus to make the cost of a trip more appealing; a second application was elaborated that optimizes the trajectories of the aircraft.
- Fuel Burn Benefits of Altitude Optimization Strategies in the Cruise Phase of LongHaul FlightsPublication . Silva, JorgeThis paper focuses on the vertical profile of the cruise phase of long-haul commercial flights covering legislation, operational standards, communications, surveillance, flight planning and performance aspects. Two case studies are presented: the first one describes and compares an actual vertical profile of a flight and an optimised one, with detailed calculations as well as results estimation; the second one compares two vertical profile optimization procedures strategies. Small modifications in how cruise phase of a flight is operated airlines can achieve cost reductions, mitigate environmental impacts, and contribute to airspace efficiency.
- The concept of aerotropolis applied to a medium-sized city and its airportPublication . Carmo, João Jóia do; Silva, Jorge; Baltazar, Maria EmiliaMovements in Faro airport have been on a constant rise even exceeding the airport capacity. Faro city has grown in the same proportion. Both occurred in a pattern that can be applied to compare with the development of an Aerotropolis. At least three steps must be taken to develop an effective Aerotropolis plan. First, the catchment area is determined based on the existing transportation network and 60-minute travel time from the airport. Second, several socioeconomic indicators within the catchment area are evaluated through different periods using GIS software. Third, catchment area and socioeconomic indicators for the Faro region are compared with layouts obtained from several examples of Aerotropolises in Europe. The Aerotropolis model created by John Kasarda has been used in several regions across Europe. One key aspect of this model is determining whether the region evolved along with the airport throughout the years. Faro, its airport and surrounding areas, are not an exception. Thus, it is possible to identify Faro development patterns of growth useful for several stakeholders: administrative authorities, airport authorities, and territory planners. Faro airport movements have been on a constant rise. Faro city has grown, probably, in the same proportion. Both growths can be compared with an Aerotropolis development. Identifying development patterns of growth will be useful for: those responsible for the distribution of services in the territory; those who oversee the airport operation and expansion; those who are responsible for combining the interests of all for the regional development.
- Perdendo Altitude: Ascensão e Declínio da INFRAEROPublication . Arantes, Elaine; Netto, Omar; Silva, JorgeO cenário brasileiro de gestão de aeroportos indica que a Empresa Brasileira de Infraestrutura Aeroportuária (INFRAERO) vem perdendo receita com seus principais aeroportos. O objetivo deste artigo é entender o que contribuiu para a ascensão e o declínio da INFRAERO. Este estudo é apoiado pelas teorias da complexidade, dos sistemas e do interesse público. Considera a base teórica e legal da privatização, regulação e desregulamentação. Trata-se de um estudo exploratório-descritivo de natureza aplicada, seguindo a estratégia do estudo de caso. Os dados primários foram coletados em entrevistas com especialistas do setor aeroportuário. Os dados secundários obtidos através da análise documental dos relatórios da INFRAERO, bem como de estudos realizados no setor aeroportuário. Até 2003, a INFRAERO era uma operadora lucrativa e respeitada em todo o mundo. A recente concessão aeroportuária brasileira levou a INFRAERO a perder receita com seus principais aeroportos e terminais de carga. O moral de seus funcionários foi profundamente abalado. Espera-se que esta pesquisa indique os motivos do declínio da INFRAERO. Os dados primários e secundários coletados também permitirão uma discussão teórico-empírica. A pesquisa apresenta relevância empírica, teórica e acadêmica. Empiricamente, os resultados desta pesquisa permitirão aos membros do setor aéreo aprender, compreendendo os fatores que transformaram uma empresa respeitada e lucrativa a entrar em um processo de declínio. Teoricamente, retomará aspectos específicos das teorias no contexto organizacional do aeroporto. Academicamente, este estudo fornecerá subsídios para a continuação da pesquisa no setor aeroportuário em todo o mundo.
- Mechanical Properties of Fused Filament Fabrication MaterialsPublication . Santos, João; Silva, Jorge; Gamboa, Pedro; Neves, JoãoThe last decades have witnessed a significant development and increased usage of additive manufacturing (AM) technologies. Among these technologies, the fused filament fabrication (FFF) is being characterized by a massive worldwide spreading, from specialized companies with high-quality equipment to the hobbyist with home-made 3D printers. Thus, and aiming to help the user achieving the best results, it is essential to continuously perform studies and analyses concerning the mechanical properties resulting from different feedstock materials and printing settings. This study covers the execution and the subsequent comparative analysis of the results of flexural and tensile tests on three different types of FFF materials: polylactic acid (PLA), acrylonitrile butadiene styrene (ABS), and CarbonFilTM. It also comprehends a parallel study of the infill setting, more specifically the testing of specimens with a 50% infill reduction. All tests were executed according to the corresponding American Society for Testing and Materials (ASTM) standards. This work aims to clarify the properties of three different materials and the effect of the internal material reduction on the mechanical properties of 3D printed objects.
- Ultralight Aviation and Hypoxia: Pilot Perspec- tives on Cerebral Oximetry MonitorizationPublication . Zorro, Sara; Silva, Jorge; Patrão, LuisThe current study features collected information from a heterogeneous group of pilots regarding their prior experiences of hypoxia. The study focuses on whether the group of assembled pilots has received hypoxia training and on their perceptions of the trainings relevancy. Also analyzed is whether the installation of a physiological monitoring system would be considered by pilots as being relevant to improving flight safety. A monitoring system for brain oximetry was tested in light aviation pilots during real flight conditions
- Air transportation: perception and impact of passengers with reduced mobilityPublication . Zorro, Sara; Macário, Rosário; Silva, JorgeAir transport has many restrictions for persons with reduced mobility (PRM). This study aims to better understand the needs of PRMs and the main constraints they face within airports and aircraft. The passengers’ air rights and how they are being met for PRMs were analysed. An online survey was used to gather information about accessibility constraints and PRMs’ perception of air travel. The specific regulations for these passengers are not being properly complied with. There is still room for both airports and airlines to improve PRM experience during air travel.
- Optimized communication plan and its impact on the contingency plan previously put in place for timely crisis response in the air sectorPublication . Piedade, Lúcia; Silva, J.Analyze the crises spread in the Organization, taking into account their effects, response time (partial and total) and entities involved. In theory, the goal is to understand how the crisis response should be and how the system responds to the same type of crisis. There is a gap in the communication plan for crisis response in place. The deepening and exploration of typologies of organizational crises in the air sector, will to optimize the response times that can satisfy or mitigate the worsening of the situations, setting off a new challenge. It is through the methodology of gathering information, readings and research of the subject literature that this will be analyzed based in success cases, typologies of crisis and also models of response time exist. The study will shine a light on the different crisis typologies as well as their propagation at the Lisbon airport. Leading to the creation of a model or models for a quick and effective response to it. Thus minimizing the response time and eventual recourse due to the analysis of success stories in similar infrastructures. The objective of this study is to study is the production of a model or several. Therefor optimizing the response time in crisis situations as a result of studies and research on typologies of crisis and their effects in time and in the entities involved.