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- Experimental study of the consequences of controlled atmosphere conservation environment on cherry characteristicsPublication . Andrade, L.P.; Nunes, José; Simões, M.P.; Morais, Diogo; Canavarro, M.C.C.; Espírito Santo, Christophe; Gaspar, Pedro Dinis; Silva, Pedro Dinho da; Resende, Mafalda; Caseiro, Catarina; Beato, Helena; Belane, Yuran; Ferreira, DoraCherry is a highly perishable fruit widely appreciated that is only commercialized during a short period. The post-harvest control and monitoring of this fruit is central and essential for optimal consumption in its highest state of quality. The conservation process aimed to inhibit the microbial propagation is usually accomplished by low temperatures and/or variable atmosphere composition. This paper describes experimental tests conducted in different refrigeration chambers located in industrial and laboratorial facilities. The latter one includes modified atmosphere and controlled atmosphere chambers. The tests were performed with four different concentration of O2 and CO2 in the controlled atmosphere chamber. Fruit samples extracted from each chamber were analyzed at specific residence times and several organoleptic characteristics were analyzed. The results show that the modified and controlled atmosphere maintain the fruit quality in terms of size, color, appearance and firmness, thus increasing their shelf life and food safety.
- The use of technology in the diagnosis and treatment of epilepsy: Trends and open issuesPublication . Fernandes, J.; Gaspar, Pedro Dinis; Menino, Eva; Caldeira, J.M.L.P.; Soares, V.N.G.J.Epilepsy is one of the most common neurological diseases in the world, affecting millions of people. The impact of this disease goes beyond seizures. It has repercussions on the individual’s health and quality of life (i.e., neurological, psychological, and physical consequences) and social inclusion. This article presents a review of the literature and discusses the technological and scientific advances in the diagnosis and treatment of epilepsy. It begins by introducing the related concepts, then analyzes the different technological approaches, exposing their strengths and limitations, and concludes by identifying challenges and open problems for future research.
- Protótipo de solução de deteção e dispersão de aves para proteção de colheitasPublication . Lourenço, Leonardo G.P.S.; Micaelo, Eduardo B.; Gaspar, Pedro Dinis; Caldeira, J.M.L.P.; Soares, Vasco N.G.J.Os animais são uma das pragas que constituem uma ameaça para a produtividade das culturas destinadas ao consumo humano. As perdas de colheitas causadas por aves representam um desafio sério e dispendioso para os agricultores. O trabalho apresentado neste artigo parte de um estudo prévio dos mesmos autores que concluiu sobre a ineficiência das técnicas dissuasoras comumente utilizadas para dispersão de aves nas colheitas. Assim, num contexto de agricultura inteligente, propõe o uso de drones, inteligência artificial, sensores e IoT, para tentar resolver este problema. Apresenta uma proposta de arquitetura e descreve o processo de implementação de um protótipo, incluindo os seus componentes de hardware e software. Descreve um conjunto de testes realizados para validação do conceito e identifica pontos de trabalho em aberto.
- Peaches detection using a deep learning technique — A contribution to yield estimation resources management, and circular economy.Publication . Assunção, Eduardo; Gaspar, Pedro Dinis; Mesquita, Ricardo; Simões, M.P.; Ramos, António Santos; Proença, Hugo; Inácio, Pedro R.M.Fruit detection is crucial for yield estimation and fruit picking system performance. Many state-of-the-art methods for fruit detection use convolutional neural networks (CNNs). This paper presents the results for peach detection by applying a faster R-CNN framework in images captured from an outdoor orchard. Although this method has been used in other studies to detect fruits, there is no research on peaches. Since the fruit colors, sizes, shapes, tree branches, fruit bunches, and distributions in trees are particular, the development of a fruit detection procedure is specific. The results show great potential in using this method to detect this type of fruit. A detection accuracy of 0.90 using the metric average precision (AP) was achieved for fruit detection. Precision agriculture applications, such as deep neural networks (DNNs), as proposed in this paper, can help to mitigate climate change, due to horticultural activities by accurate product prediction, leading to improved resource management (e.g., irrigation water, nutrients, herbicides, pesticides), and helping to reduce food loss and waste via improved agricultural activity scheduling.
- The development of a prototype solution for detecting wear and tear in pedestrian crossingsPublication . Rosa, Gonçalo J.M.; Afonso, João M.S.; Gaspar, Pedro Dinis; Soares, Vasco N.G.J.; Caldeira, J.M.L.P.Crosswalks play a fundamental role in road safety. However, over time, many suffer wear and tear that makes them difficult to see. This project presents a solution based on the use of computer vision techniques for identifying and classifying the level of wear on crosswalks. The proposed system uses a convolutional neural network (CNN) to analyze images of crosswalks, determining their wear status. The design includes a prototype system mounted on a vehicle, equipped with cameras and processing units to collect and analyze data in real time as the vehicle traverses traffic routes. The collected data are then transmitted to a web application for further analysis and reporting. The prototype was validated through extensive tests in a real urban environment, comparing its assessments with manual inspections conducted by experts. Results from these tests showed that the system could accurately classify crosswalk wear with a high degree of accuracy, demonstrating its potential for aiding maintenance authorities in efficiently prioritizing interventions.
- Energy life-cycle assessment of fruit products - Case study of Beira Interior’s peach (Portugal)Publication . Gaspar, João Pires; Gaspar, Pedro Dinis; Silva, Pedro Dinho da; Simões, M.P.; Espírito Santo, ChristopheCurrently, there is a growing demand for cleaner and sustainable technologies due to environmental issues. In this sense, there is a necessity to manage the assessment of production processes and the rationalization of energy consumption. In this study, an Energy Life-Cycle Assessment (ELCA) was carried out through energy efficiency indicators, directed to the characterization and renewability of the peach production system life-cycle in the Portuguese region of Beira Interior. The study intends to investigate the non-renewable energy inputs from fossil fuels, as well as the emissions resulting from machinery. In addition, warehouse energy inputs are analyzed, mainly cooling systems of refrigerated chambers where fruits are preserved. This analysis aims to find opportunities for technological, environmental and best practices improvements. Test scenarios were analyzed and revealing soil groundcover maintenance is the operation with the largest impact in the energy consumption of the production process (3176 MJ·ha−1 ). In the post-harvest processes, the energy consumption largest impact is given by the warehouse’s operations (35,700 MJ·ha−1 ), followed by transportation (6180 MJ·ha−1 ). Concerning the emissions resulting from the fuels consumption, the largest impact is due to the plantation machinery and the transportation from warehouse to retailers
- GPS-based autonomous navigation system for multitask robotic rover for agricultural activities with augmented reality web application for supervision support on peach orchardsPublication . Menezes, G.; Gaspar, Pedro Dinis; Mesquita, Ricardo; Assunção, Eduardo; Simões, M.P.As a result of the increasing world population and the growing demand for food, there is a great need to increase agricultural productivity. However, the problem is aggravated by the population migration from rural areas to cities, which causes a decrease in the workforce in the agricultural sector. In this regard, within the concept of agriculture 4.0, the introduction of autonomous robots in agricultural activities may face these problems, supporting the growing lack of labor and promoting increased agricultural productivity. This work exposes the algorithm used to perform autonomous navigation, based on global positioning systems (GPS), of the robotic rover for agricultural applications (R2A2) multitasking aimed at performing herbicide spraying. An augmented reality (AR) web application has also been developed to assist in the supervision of autonomous vehicles. A code in C/C++ was developed for the autonomous movement of the robotic platform using an Arduino Mega2560 as the main microprocessor and the AR web application based on the positioning which was developed using the AR.JS libraries and the A-FRAME framework compiled in a code HTML. The application was tested in a peach orchard and presented an average of approximately 94% of correct answers, which reveals the accuracy of the technological solution developed. Also exposed are the results and conclusions of the autonomous movement algorithm and the web application.
- Desenho e implementação de protótipo para deteção de contentores de resíduos em cidades inteligentesPublication . Valente, Miguel; Silva, Hélio; Caldeira, J.M.L.P.; Soares, V.N.G.J.; Gaspar, Pedro DinisEste trabalho apresenta o desenho e implementação de um protótipo funcional para avaliar e validar a utilização de técnicas de visão computacional, na identificação de contentores de resíduos no contexto de uma cidade inteli- gente. Este protótipo recorre à utilização de uma rede neuronal convolucional YOLO e de um microcomputador Jetson Nano da Nvidia. Comparativamente ao método atual de identificação de contentores de resíduos por radiofrequência, esta abordagem é mais ágil e diminui os recursos necessários para implementa- ção, contribuindo para poupar nos gastos logísticos e de implementação da gestão inteligente de resíduos.
- The effect of controlled atmosphere storage on fruit quality and postharvest performance of ‘Sweet Henry’ peach cultivarPublication . Veloso, Abel; Gaspar, Pedro Dinis; Andrade, L.P.; Espírito Santo, Christophe; Resende, Mafalda; Silva, Pedro Dinho da; Teixeira, M.C.C.; Simões, M.P.Peach is a highly perishable climacteric fruit. Cold storage is the most widely used method for peach storage, delaying fruit deterioration. This study describes the experimental tests developed to evaluate the evolution of peach characteristics under different storage conditions of controlled (CA) and normal atmosphere (NA) of ‘Sweet Henry’ cultivar. Tests were performed in refrigeration chambers in industrial and laboratory facilities, throughout 2years. In the controlled atmosphere chamber, the tests were performed with 3different concentrations of O2 and CO2, namely 3 treatments of controlled atmosphere (2% O2-5% CO2, 2% O2-10%CO2and 2% O2-15% CO2), 2treatments of normal atmosphere (at Research Centre and at FarmersOrganization facilities). From each treatment, peach samples were extracted and analyzed at 14, 21, 28, 35 (for all treatments) and at 42, 49, and 56 days(for controlled atmosphere). The analysis of the biometric parameters NDASHsize, weight, color, firmness, total soluble solids, acidity – were performed inorder to evaluate peach quality. In FO treatment, a weight loss of -13% in 2020 and -11% in 2021 was observed after 35 days. In NA treatment the maximum weight loss was -5% after 35 days of storage. A decrease of fruit firmness and acidity content was observed in all the treatments throughout time, but firmness remain globally similar between CA treatments. The CA treatments maintained the fruit quality in terms of weight, and firmness, thus increasing fruit market life. First chilling injury (CI) symptoms were observed at 35 + 2days of storage. The treatment 2% O2-15% CO2 allowed fruit firmness maintenance, the minimal decrease of acidity content and low CI incidence of Sweet Henry cultivar for a storage period of 56 days.
- Road pavement damage detection using computer vision techniques: Approaches, challenges and opportunitiesPublication . Gonçalves, Miguel; Marques, Tomás; Gaspar, Pedro Dinis; Soares, V.N.G.J.; Caldeira, J.M.L.P.Este artigo apresenta uma visão geral e os resultados de uma investigação preliminar que visa a utilização de técnicas de visão computacional para deteção de defeitos em pavimentos rodoviários, no contexto de uma cidade inteligente. Primeiro introduz os conceitos relacionados. Em seguida, faz um levantamento do estado da arte e das soluções existentes, apresentando as suas principais características, pontos fortes e limitações. São identificadas as soluções mais promissoras. Para finalizar discute desafios em aberto e direções de investigação nesta área.