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- Identification of landmines in thermal infrared imagesPublication . Pimenta, Jorge LeitãoThis paper explores the detection of landmines using thermal images acquired in military context. The conditions in which the images are obtained have a direct influence on the methods used to perform the automatic detection of landmines through image processing techniques. The proposed methodology follows two main phases: acquisition of thermal images and its processing. In the first phase, four different experiences were prepared to analyze the factors that influence the quality of the detection. In the second phase was conducted the image processing on a set of images based on classification techniques using the K-Nearest Neighbor (KNN) and Support Vector Machine (SVM) algorithms. The classification was performed on a set of features extracted from ROI’s obtained by a sliding window. A second approach was also implemented based on segmentation using thresholds. The results achieved allow to identify factors that influence the detection of the mines: the burial depth, the presence of vegetation on the surface and the time of the day at which images were obtained. The optimal classification was obtained with the KNN classifier with 40 features selected with Sequential Backward Selection (SBS), and using the distance metric of correlation.
- Image fusion for the detection of camouflaged peoplePublication . Bento, Nádia Alexandra FerreiraThe use of thermal imaging is a benefit for the Armed Forces. Due to their advantages, they have a large number of applications, including the detection of camouflaged people. For better results, the thermal information can be merged with the color information which allows a greater detail, resulting in a greater degree of security. The present study implemented as pixel level image fusion methods: Principal Components Analysis; Laplacian Pyramid; and Discrete Wavelet Transform. A qualitative analysis concluded that the method which performs better is the one that uses Wavelets, followed by the Laplacian Pyramid and finally the PCA. A quantitative analysis was made using as performance metrics: Standard Deviation, Entropy, Spatial Frequency, Mutual Information, Fusion Quality Index and Structural Similarity Index. The values obtained support the conclusions drawn from the qualitative analysis. The Mutual Information, Fusion Quality Index and Structural Similarity Index are the appropriate metrics to measure the quality of image fusion as they take into account the relationship between the fused image and the input images.
- Automatic classification of green areas for cartography purposesPublication . Dias, Joel Augusto Joanaz D’AssunçãoThis paper exposes a study with the purpose of discriminating the different types of vegetation. One way to get information about the land is through cartography, where aerial photogrammetry is one of the most used techniques. The main objective of this study is the development of a tool capable of processing aerial photographs on the visible spectrum and for it to be able to discern and classify the different types of vegetation. The adopted methodology comprises into three major steps: feature extraction, feature selection and image classification using two classifiers, K-Nearest Neighbors and Support Vector Machine. The first step extracts statistical features and features of texture, the second step implements a technique that allows the selection of the most relevant features and the last step is divided in the optimization of the classifiers input parameters and subsequent image classification. It was not possible to use the eight classes pre-defined due to the similarity between some of them, which led to the merge of some, resulting in four new classes. The images were classified according the new classes and the performance of the two classifiers was compared. It was found that the best classifier is the Support Vector Machine using the function of kernel Radial Basis Function showing 89,8% of correct classifications. The influence of the feature selector was tested and it was concluded that it led to an average increase of 8,25% in the classifier’s performance. It was also concluded that the best results were achieved with 10 features for the KNearest Neighbors and with 20 features for the Support Vector Machine.
- New Ways to Deal with Omni-Channel Services: Opening the Door to Synergies, or Problems in the Horizon?Publication . Reis, João Carlos Gonçalves dos; Amorim, Marlene Paula Castro; Melão, Nuno Filipe RosaThis article aims to investigate organizational synergies in the omnichannel service context. In doing so, it discloses new omni-channel trends and discusses its implications for managers and academics. It uses a qualitative multimethod approach, which includes more than one method of collecting data to generate comprehensiveness and rich knowledge, namely: a systematic literature review and a case study. The transition to an omni-channel service requires companies to overcome many organizational challenges and is compelling academics and practitioners to focus on its operations management. The results indicate that organizational synergies are changing the omni-channel landscape and may provide several opportunities for gaining competitive advantages by implementing new technologies (e.g. m-payments), and anticipating customer needs (e.g. multi-brand experience). It is possible that these organizational synergies are transcending the omni-channel concept, creating new trends, but to confirm this hypothesis further investigation is needed.
- Breaking Barriers with Qualitative Multi-method Research for Engineering Studies: Pros, Cons and IssuesPublication . Reis, João Carlos Gonçalves dos; Amorim, Marlene Paula Castro; Melão, Nuno Filipe RosaThe purpose of this article is to investigate how contemporary studies about engineering are breaking down boundaries of knowledge. This study uses a systematic literature review to show how the application of qualitative multi-method approaches may offer reliable results and provide greater emphasis to the dimensions of development, triangulation and complementarity. The article offers new insights on the role of qualitative researches for the engineering domain, an area which has been largely unaddressed in the literature.
- Powerpoint Presentation "New Ways to Deal with Omni-Channel Services: Opening the Door to Synergies, or Problems in the Horizon?" 8th International Conference on Exploring Service Science, Rome, Italy 2017Publication . Reis, João Carlos Gonçalves dos; Amorim, Marlene Paula Castro; Melão, Nuno Filipe Rosa
- Omni-channel service operations: Building technology-based business networksPublication . Reis, João Carlos Gonçalves dos; Amorim, Marlene Paula Castro; Melão, Nuno Filipe RosaThis article investigates how omni-channel services operations are building technology-based business networks. It uses a case study research, which includes multiple sources of data collection for triangulation purposes, to study a real-life phenomenon. The results suggest that omni-channel companies are changing their landscape to business networks, looking for competitive advantages over their rivals. But this move incorporates new challenges, as it requires a transition based on operations management to allow these firms to adapt their processes and channels, in order to be able to collaborate in a heterogeneous network of firms. Another possible solution is the integration of innovation technologies that are enabling the combination of firm capabilities to underpin collaborative relationships. Previous research also suggests that service operations management in an omni-channel services context is largely unaddressed, as this discipline is essential for the edification of technology-based business networks. Thereby, this article provides real-life statements and examples of firms that are moving their service operations into a business network paradigm. Subsequently, since omni-channel services are multidisciplinary in nature, these exploratory results represent a fruitful opportunity for future research to involve other disciplines than service operations.
- Multichannel service failure and recovery in a O2O era: A qualitative multi-method research in the banking services industryPublication . Reis, João Carlos Gonçalves dos; Amorim, Marlene Paula Castro; Melão, Nuno Filipe RosaThis article aims to investigate how service providers are employing their channels to support the handling of customer complaints in an online to offline era. It provides a timely contribution by characterizing multichannel recovery practices, discussing its implications for customers, and discovering new trends. The study employs a qualitative multi-method research, which includes not only more than one method of collecting data, but also more than one method of analyzing data. Data collection involved 50 records of customer complaints, 10 semi-structured interviews, direct observation and internal bank reports. The results suggest that multichannel customers are not willing to interact with a large number of channels to solve their problems leading to a high number of interactions. Customers expect a complex recovery not in terms of interactivity but in terms of depth. Recovery solutions, such as apologizing and monetary compensations are non-permanent solutions, that are inefficient in the long term and imply financial losses. Despite the investment that is required, this investigation advocates for permanent solutions. To avoid service failures and complex recovery processes, it is possible that companies are improving their operations management in search of new strategies that are blurring the boundaries of O2O into a mix of offline and online channels (O2).
- Digital Transformation: A Literature Review and Guidelines for Future ResearchPublication . Reis, João Carlos Gonçalves dos; Amorim, Marlene Paula Castro; Melão, Nuno Filipe Rosa; Matos, Patrícia Sofia LopesThe aim of this paper is to provide insights regarding the state of the art of Digital Transformation, and to propose avenues for future research. Using a systematic literature review of 206 peer-reviewed articles, this paper provides an overview of the literature. Among other things, the findings indicate that managers should adapt their business strategy to a new digital reality. This mainly results in the adaptation of processes and operations management. Scholars, for the other side, are also facing challenges, as prior research may not have identified all the opportunities and challenges of Digital Transformation. Furthermore, while the Digital Transformation has expanded to all sectors of activity there are some areas with more prospects of being developed in the future than others.
- Industrial Engineering and Operations Management IPublication . Reis, João Carlos Gonçalves dos; Pinelas, Sandra; Melão, Nuno Filipe RosaBased on the 2018 International Joint Conference on Industrial Engineering and Operations Management (IJCIEOM) conference that took place in Lisbon, Portugal, this proceedings volume is the first of two focusing on mathematical applications in digital transformation. The different contributions in this volume explore topics such as modelling, simulation, logistics, innovation, sustainability, health care, supply chain, lean manufacturing, operations management, quality and digital. Written by renowned scientists from around the world, this multidisciplinary volume serves as a reference on industrial engineering and operations management and as a source on current findings for researchers and students aiming to work on industrial-related problems.
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