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Publications

2025

Digital assessment of plant diseases: A critical review and analysis of optical sensing technologies for early plant disease diagnosis

Authors
Pereira, MR; Tosin, R; dos Santos, FN; Tavares, F; Cunha, M;

Publication
COMPUTERS AND ELECTRONICS IN AGRICULTURE

Abstract
The present critical literature review describes the state-of-the-art innovative proximal (ground-based) solutions for plant disease diagnosis, suitable for promoting more precise and efficient phytosanitary measures. Research and development of new sensors for this purpose are currently a challenge. Present procedures and diagnosis techniques depend on visual characteristics and symptoms to be initiated and applied, compromising an early intervention. Also, these methods were designed to confirm the presence of pathogens, which did not have the required high throughput and speed to support real-time agronomic decisions in field extensions. Proximal sensor-based systems are a reasonable tool for an efficient and economic disease assessment. This work focused on identifying the application of optical and spectroscopic sensors as a tool for disease diagnosis. Biophoton emission, fluorescence spectroscopy, laser-induced breakdown spectroscopy, multi- and hyperspectral spectroscopy (HS), nuclear magnetic resonance spectroscopy, Raman spectroscopy, RGB imaging, thermography, volatile organic compounds assessment, and X-ray fluorescence were described due to their relevant potential. Nevertheless, some techniques revealed a low technology readiness level (TRL). The main conclusions identify HS, single and multi-spatial point observation, as the most applied methods for early plant disease diagnosis studies (88%), combined with distinct feature selection (FeS), dimensionality reduction (DR), and modeling techniques. Vegetation indices (28%) and principal component analysis (19%) were the most popular FeS and DR approaches, highlighting the most relevant wavelengths contributing to disease diagnosis. In modeling, classification was the most applied technique (80%), used mainly for binary and multi-class health status identification. Regression was used in the remaining (21%) scientific works screened. The data was collected primarily in laboratory conditions (62%), and a few works were performed in field conditions (21%). Regarding the study's etiological agent responsible for causing the disease, fungi (53%) and viruses (23%) were the most analyzed group of pathogens found in the literature. Overall, proximal sensors are suitable for early plant disease diagnosis before and after symptom appearance, presenting classification accuracies mostly superior to 71% and regression coefficients superior to 61%. Nevertheless, additional research regarding the study of specific host-pathogen interactions is necessary.

2025

Object segmentation dataset generation framework for robotic bin-picking: Multi-metric analysis between results trained with real and synthetic data

Authors
Cordeiro, A; Rocha, LF; Boaventura-Cunha, J; Pires, EJS; Souza, JP;

Publication
Computers & Industrial Engineering

Abstract

2025

Nonlinear Control of Mecanum-Wheeled Robots Applying H8Controller

Authors
Chellal, AA; Braun, J; Lima, J; Gonçalves, J; Valente, A; Costa, P;

Publication
IEEE International Conference on Autonomous Robot Systems and Competitions, ICARSC 2025, Funchal, Portugal, April 2-3, 2025

Abstract
The growing demand for highly maneuverable mobile robots today drives Mecanum-wheeled robot popularity in industrial automation, logistics, and service robotics. These omnidirectional robots have features that enable them to run appropriately in conditions requiring exact motion control. Nevertheless, low-level control techniques for these robots are still challenging to apply because of their nonlinear dynamics and external perturbations, including wheel friction and slip-page.

2025

MANAGER-JOB FIT ON INDIVIDUAL AND GROUP JOB PERFORMANCE

Authors
SAMUL, J; e CUNHA, JF;

Publication
Scientific Papers of Silesian University of Technology. Organization and Management Series

Abstract

2025

Dissipative pulses stabilized by nonlinear gradient terms: A review of their dynamics and their interaction

Authors
Descalzi, O; Facao, M; Carvalho, MI; Cartes, C; Brand, HR;

Publication
PHYSICA D-NONLINEAR PHENOMENA

Abstract
We study the dynamics as well as the interaction of stable dissipative solitons (DSs) of the cubic complex Ginzburg-Landau equation which are stabilized only by nonlinear gradient (NLG) terms. First we review stationary, periodic, quasi-periodic, and chaotic solutions. Then we investigate sudden transitions to chaotic from periodic and vice versa as a function of one parameter, as well as different outcomes, for fixed parameters, when varying the initial condition. In addition, we present a quasi-analytic approach to evaluate the separation of nearby trajectories for the case of stationary DSs as well as for periodic DSs, both stabilized by nonlinear gradient terms. In a separate section collisions between different types of DSs are reviewed. First we present a concise review of collisions of DSs without NLG terms and then the results of collisions between stationary DSs stabilized by NLG terms are summarized focusing on the influence of the nonlinear gradient term associated with the Raman effect. We point out that both, meandering oscillatory bound states as well as bound states with large amplitude oscillations appear to be specific for coupled cubic complex Ginzburg-Landau equations with a stabilizing cubic nonlinear gradient term.

2025

Preface

Authors
Simoes, A; Dalmarco, G; Rodrigues, JC; Zimmermann, R;

Publication
Springer Proceedings in Business and Economics

Abstract
[No abstract available]

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