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Publications

2023

Filling the maize yield gap based on precision agriculture-A MaxEnt approach

Authors
Norberto, M; Sillero, N; Coimbra, J; Cunha, M;

Publication
COMPUTERS AND ELECTRONICS IN AGRICULTURE

Abstract
Precision agriculture (PA) and yield gap (Yg) analysis are promising strategies to achieve the desired sustainable intensification of agricultural production systems. Current crop Yg approaches do not consider the internal field yield variability caused by soil properties. Topographic and edaphic characteristics causing consistent high and low yield patterns in time and space can be interpreted as an ecological niche and used as proxies for potential yield (Yp) and Yg. Ecological niche models (ENMs) are statistical models originally developed to forecast a species' niche. However, its application to analyse crop yield spatio-temporal variability has never been made. This study aimed to fill this void by developing a novel approach: i) to quantify the magnitude and spatiotemporal distribution of Yp and Yg, ii) to identify the main factors that cause the Yg, and iii) to provide statistical and agronomical interpretation of the data to reduce the Yg. We performed this work using high-resolution maize yield maps from three seasons, with an ancillary dataset composed of soil electrical conductivity, soil properties and digital elevation models provided by Quinta da Cholda, Portugal. The yield maps were averaged, resulting in a standardised multiyear yield map. The 90th and 10th yield percentiles were interpreted as proxies for Yp and Yg, and analysed by an ENM machine learning algorithm - maximum entropy (MaxEnt). The average Yg and Yp were quantified as 1.5 and 19.1 ton/ha. Yp was characterised by having silty, richer soils and lower elevations, with several nutritional factors above the critical limits to maintain higher yields. Yg had loam soils coupled with higher relative elevations and lower nutrition content. This innovative modelling approach can efficiently manage high-dimensional spatio-temporal data to support advanced PA solutions, allowing detailed support for narrowing the Yg.

2023

NOVA PLANTA DO CASTELO VELHO DE SAFARA: INTEGRAÇÃO DE DADOS ARQUEOLÓGICOS COM TOPOGRAFIA DE ALTA RESOLUÇÃO DERIVADA DE LEVANTAMENTO DRONE-LIDAR

Authors
Monge Soares, R; Nabais, M; Pereiro, TD; Dias, R; Hipólito, J; Fonte, J; Gonçalves Seco, L; Menéndez-Marsh, F; Neves, A;

Publication
Estudos do Quaternário / Quaternary Studies

Abstract
Resumo:Com este estudo apresenta-se uma nova perspectiva tridimensional do Castelo Velho de Safara (Moura), um dos grandes povoados muralhados da Idade do Ferro/período Romano Republicano existentes na linha do Rio Guadiana, criada a partir de um levantamento de alta resolução realizado com sensor LiDAR acoplado a um drone. O resultado obtido permitiu a definição detalhada da planta da muralha, o que implicou a revisão da superfície de ocupação, que agora é estimada em cerca de 1.36 hectares. Foram também identificados vários elementos inéditos, como a zona da entrada e eventuais soluções de reforço defensivo. Os dados obtidos para o Castelo Velho de Safara demonstram o potencial dos dados LiDAR para o reconhecimento das características topográficas deste tipo de recintos fortificados, cuja visibilidade das estruturas nem sempre é possível a olho nu.Palavras-chave: Idade do Ferro; Período Romano Republicano; Estruturas defensivas; Drone; LiDAR.   Abstract:This study presents a new tridimensional perspective on Castelo Velho de Safara (Moura), one of the great walled settlements of the Iron Age/Roman Republic by the Guadiana River, obtained through a high-resolution survey using a drone integrated with a LiDAR sensor. The outline of the walls was defined in more detail, which meant revising the occupation area, now estimated at circa 1.36 hectares. Several unknown elements were detected, such as the entrance area and other possible defensive structures. The data obtained for the Castelo Velho de Safara demonstrate the potential of LiDAR for understanding the topographical characteristics of this type of fortified enclosure, whose structural remains are not always clear to the naked eye.Keywords: Iron Age; Roman Republic; Defensive structures; Drone; LiDAR; Odyssey.

2023

Editorial: Explainability in knowledge-based systems and machine learning models for smart grids

Authors
Santos, G; Pinto, T; Ramos, C; Corchado, JM;

Publication
FRONTIERS IN ENERGY RESEARCH

Abstract
[No abstract available]

2023

Sensor Integration in a Forestry Machine

Authors
Pereira, T; Gameiro, T; Viegas, C; Santos, V; Ferreira, N;

Publication
SENSORS

Abstract
This paper presents the integration of multimodal sensor systems for an autonomous forestry machine. The utilized technology is housed in a single enclosure which consolidates a set of components responsible for executing machine control actions and comprehending its behavior in various scenarios. This sensor box, named Sentry, will subsequently be connected to a forestry machine from MDB, model LV600 PRO. The article outlines previous work in this field and then details the integration and operation of the equipment, integrated into the forest machine, providing descriptions of the adopted architecture at both the hardware and software levels. The gathered data enables the assessment of the forestry machine's orientation and position based on the information collected by the sensors. Finally, practical experiments are presented to demonstrate the system's behavior and to analyze the methods to be employed for autonomous navigation, thereby assessing the performance of the established architecture. The novel aspects of this work include the physical and digital integration of a multimodal sensor system on a forestry machine, its use in a real case scenario, namely, forest vegetation removal, and the strategies adopted to improve the machine localization and navigation performance on unstructured environments.

2023

THE EUNIVERSAL PORTUGUESE DEMONSTRATOR: FROM MV-LV COORDINATED IDENTIFICATION OF FLEXIBILITY NEEDS TO ACTIVATION THROUGH THE UMEI

Authors
Mourão, RL; Gouveia, C; Sampaio, G; Retorta, F; Merckx, C; Benothman, F; Águas, A; Boto, P; Silva, CD; Milzer, G; Marzano, G; Dumont, C; Crucifix, P; Kaffash, M; Heylen, E;

Publication
IET Conference Proceedings

Abstract
The EUniversal project, funded by the European Union, aims to establish a universal approach to the utilization of flexibility by Distribution System Operators (DSOs) and their engagement with new flexibility markets. To achieve this objective, the project team has focused on developing the Universal Market Enabling Interface (UMEI) concept. This paper presents an overview of the process of adapting grid core systems to interact with different market platforms and agents, which is a key aspect of the real-world demonstration set to take place in Portugal. © The Institution of Engineering and Technology 2023.

2023

A Hybrid BRKGA for Joint Scheduling Production, Transport, and Storage/Retrieval in Flexible Job Shops

Authors
Homayouni, SM; Fontes, DBMM; Fontes, FACC;

Publication
PROCEEDINGS OF THE 2023 GENETIC AND EVOLUTIONARY COMPUTATION CONFERENCE COMPANION, GECCO 2023 COMPANION

Abstract
This paper addresses the joint scheduling of production operations, transport tasks, and storage/retrieval activities in flexible job shop systems where the production operations and transport tasks can be done by one of the several resources available. Jobs need to be retrieved from storage and delivered to a load/unload area, from there, they are transported to and between the machines where their operations are processed on. Once all operations of a job are processed, the job is taken back to the load/unload area and then returned to the storage cell. Therefore, the problem under study requires, concurrently, solving job routing, machine scheduling, transport allocation, vehicle scheduling, and shuttle schedule. To this end, we propose a hybrid biased random-key genetic algorithm (BRKGA) in which the mutation operator resorts to six local search heuristics. The computational experiments conducted on a set of benchmark instances show the effectiveness of the proposed mutation operator.

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