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Pegada de carbono do caju em diferentes sistemas de cultivo: métodos de quantificação de gases de efeito estufa e projeções

Thu, 01 Jan 2026 00:00:00 GMT

Título: Pegada de carbono do caju em diferentes sistemas de cultivo: métodos de quantificação de gases de efeito estufa e projeções Autor(es): Sales, Jonnathan Richeds da Silva Abstract: In the face of the climate crisis, food supply chains are increasingly seeking to implement sustainable production practices; for example, studies focused on the fruit sector. Cashew farming plays an important socioeconomic role in agriculture in Brazil, especially in the Northeast region. Thus, the objective was to evaluate, compare, and integrate methodological approaches for estimating the carbon footprint in Brazilian cashew farming, considering both life cycle inventories based on empirical equations and the dynamics of carbon in biomass and soil throughout the useful life of the orchards. Initially, different methods for quantifying GHGs in a conventional cashew production system were evaluated. The Nemecek-Calc, WFLDB, IPCC-Calc, BR-Calc, and Agri-footprint methodologies were compared according to ISO 14067 standard. The results showed variations of up to 24.5% between the methods, with N₂O being the main contributor to emissions. Based on criteria of methodological clarity, scientific robustness, and suitability to regional data, the WFLDB, IPCC-Calc, and BR-Calc methods showed the best performance. In a second stage, the carbon footprint was integrated with the quantification of carbon stored in biomass and the modeling of soil organic carbon (SOC) throughout the cashew tree's production cycle, considering a lifespan of 25 years. Five production systems were evaluated in experimental and commercial areas, including monoculture and intercropping systems. Biomass was quantified using specific allometric equations, and the SOC (0–20 cm) was estimated using the RothC model. The results demonstrated greater carbon accumulation in biomass and soil in diversified systems, reflecting lower carbon footprint values compared to conventional systems. It is concluded that the methodological choice and management system significantly influence the carbon footprint results in cashew farming, highlighting the potential of diversified production systems as a strategy for mitigating climate change and supporting the sustainability of the sector. Tipo: Tese

Desenvolvimento e validação de sistema vestível para monitoramento de cães de busca e resgate

Wed, 01 Jan 2025 00:00:00 GMT

Título: Desenvolvimento e validação de sistema vestível para monitoramento de cães de busca e resgate Autor(es): Viana, Vinícius de Sena Sales Abstract: The operational efficiency of cynotechnical teams in search and rescue missions is conditioned by communication effectiveness and the monitoring of canine behavioral patterns. However, remote supervision in scenarios of high structural complexity or dense vegetation still faces tactical and technological limitations. This study aimed to develop a monitoring system for search and rescue dogs, which comprised the engineering of a transmitter prototype based on a microcontroller, integrating an accelerometer, a gyroscope, and a sound detector. The system underwent an experimental protocol with dogs from the Search Dog Company (CBCães/CBMCE). Results showed that the fusion of kinematic and sound data enabled the identification of resting, displacement, and alert barking states with an overall accuracy of 98.70%. The LoRa protocol ensured the stability of real-time telemetric transmission with a reduced standard deviation (± 0.35), providing objective metrics for the handler's decision-making. In conclusion, the device demonstrates high technical and operational robustness, mitigating the subjectivity of human observation and optimizing assertiveness in victim localization in disaster scenarios. Tipo: Tese

Aerodinâmica de caixas de transporte de aves

Wed, 01 Jan 2025 00:00:00 GMT

Título: Aerodinâmica de caixas de transporte de aves Autor(es): Lima, Victor Abreu de Abstract: Poultry transportation presents a significant challenge to animal welfare, particularly when birds are exposed to thermal stress during travel, a condition that can compromise physiological stability, performance, and survival. Despite the relevance of this issue, research on engineering improvements in poultry transport crates remains limited. In this study, four poultry transport crates models were evaluated to determine their potential to improve thermal comfort and internal airflow conditions. Computational Fluid Dynamics (CFD) simulations were performed at three transport speeds, complemented by wind tunnel experiments using reduced-scale prototypes manufactured by additive manufacturing. The CFD simulation results demonstrated that alternative crate model 3 (AC3) exhibited higher average internal airflow velocities (IAFV) at all speeds, including a 32.85% increase compared to the conventional Brazilian crate (CC) at 60 km/h. Wind tunnel tests confirmed significant differences between the crates. AC3 presented lower air temperature than AC1 and reduced relative humidity compared to CC and AC2. Bioclimatic indices corroborated these results, with AC3 presenting the lowest THI and enthalpy, indicating a less stressful microclimate. In terms of airflow, AC2 and AC3 achieved higher IAFV (19.27 ± 8.49 m/s and 19.30 ± 4.80 m/s) than AC1 and CC. AC3 also presented the lowest dynamic pressure, suggesting less resistance to airflow and more efficient aerodynamics. Therefore, the improved geometry of the boxes and the increase in ventilation surface area may improve airflow distribution, potentially reducing heat accumulation and improving animal welfare. However, further studies involving live birds, realistic stocking densities, and full-scale trailer simulations are needed to validate these benefits under commercial transport conditions. Tipo: Tese

Agricultura digital 4.0 em compost barn: monitoramento ambiental e soluções de manejo baseadas em microcontroladores

Wed, 01 Jan 2025 00:00:00 GMT

Título: Agricultura digital 4.0 em compost barn: monitoramento ambiental e soluções de manejo baseadas em microcontroladores Autor(es): Peixoto, Maria Simone Mendes Abstract: This study aimed to investigate structural and environmental aspects, as well as to propose technological solutions based on microcontrollers for compost barn systems on dairy farms located in the state of Ceará, Brazil. Initially, the main concepts, limitations, and advancements of the topic are presented. In Chapter 1, the environmental dynamics of dairy cow housing were evaluated using geostatistics in six farms during the dry season. Microclimatic characteristics, construction aspects, bedding management, animals’ physiological responses, and the degree of producer satisfaction were investigated. It was observed that the animals remained under severe heat stress, especially in the afternoon. The influence of stocking density and barn typology on thermal comfort and bedding uniformity was also confirmed. Regarding the degree of producer satisfaction, interviewees identified the implementation costs as a limiting factor but expressed a high level of satisfaction with the system. The results highlight the challenges of adopting this system for dairy cattle housing in semi-arid regions. In Chapter 2, a portable device based on the Internet of Things (IoT) was developed for compost barn systems. Initially, the necessary electronic components for assembling the prototype were selected and acquired. The development occurred gradually, with three successive versions: the first based on Arduino UNO R3, and the following versions with ESP32, additional sensors, and improvements in power supply and display. Performance tests of the prototype were carried out on commercial dairy farms and in a laboratory at the Federal University of Ceará. In the field phase, bedding temperature results obtained with conventional devices were compared to those from the proposed prototype, with statistically significant differences (p < 0.05) in some layers. These findings indicate the need for further studies, especially regarding the stabilization time of the DS18B20 sensor. As for data storage, no losses were recorded, even with oscillations or connection failures, as all information was successfully saved to a memory card. The device demonstrated satisfactory performance in measuring environmental and bedding thermal variables, with potential application in the intelligent management of compost barn facilities in semi-arid climates. Tipo: Tese