Articles de revista
http://hdl.handle.net/2117/665
2024-03-28T11:05:37ZObservation and measurement of ice morphology in foods: a review
http://hdl.handle.net/2117/400871
Observation and measurement of ice morphology in foods: a review
Pérez Bermúdez, Irina; Castillo Suero, Alison; Cortés Inostroza, Anielka; Jeldrez, Cristóbal; Dantas, Adriana; Hernández Yáñez, Eduard; Orellana Palma, Patricio; Petzold, Guillermo
Freezing is an effective technology with which to maintain food quality. However, the formation of ice crystals during this process can cause damage to the cellular structure, leading to food deterioration. A good understanding of the relationship between food microstructure and ice morphology, as well as the ability to effectively measure and control ice crystals, is very useful to achieve high-quality frozen foods. Hence, a brief discussion is presented on the fundamentals/principles of optical microscopic techniques (light microscopy), electronic microscopic techniques (transmission electron microscopy (TEM) and scanning electron microscopy (SEM)), as well as other non-invasive techniques (X-rays, spectroscopy, and magnetic resonance) and their application to measuring ice formation rates and characterizing ice crystals, providing insight into the freezing mechanisms as well as direct monitoring of the entire process. And, in addition, this review compares (the negative and positive aspects of) the use of simple and cheap but destructive technologies (optical microscopy) with detailed microscopic technologies at the micro/nanometer scale but with pretreatments that alter the original sample (SEM and TEM), and non-destructive technologies that do not require sample preparation but which have high acquisition and operational costs. Also included are images and examples which demonstrate how useful an analysis using these techniques can be.
2024-02-02T11:56:03ZPérez Bermúdez, IrinaCastillo Suero, AlisonCortés Inostroza, AnielkaJeldrez, CristóbalDantas, AdrianaHernández Yáñez, EduardOrellana Palma, PatricioPetzold, GuillermoFreezing is an effective technology with which to maintain food quality. However, the formation of ice crystals during this process can cause damage to the cellular structure, leading to food deterioration. A good understanding of the relationship between food microstructure and ice morphology, as well as the ability to effectively measure and control ice crystals, is very useful to achieve high-quality frozen foods. Hence, a brief discussion is presented on the fundamentals/principles of optical microscopic techniques (light microscopy), electronic microscopic techniques (transmission electron microscopy (TEM) and scanning electron microscopy (SEM)), as well as other non-invasive techniques (X-rays, spectroscopy, and magnetic resonance) and their application to measuring ice formation rates and characterizing ice crystals, providing insight into the freezing mechanisms as well as direct monitoring of the entire process. And, in addition, this review compares (the negative and positive aspects of) the use of simple and cheap but destructive technologies (optical microscopy) with detailed microscopic technologies at the micro/nanometer scale but with pretreatments that alter the original sample (SEM and TEM), and non-destructive technologies that do not require sample preparation but which have high acquisition and operational costs. Also included are images and examples which demonstrate how useful an analysis using these techniques can be.Price transmission during food safety incidents: The case of Spanish tuna fraud
http://hdl.handle.net/2117/400152
Price transmission during food safety incidents: The case of Spanish tuna fraud
Jin, Yan; Gil Roig, José María
Using a two-regime threshold vector autoregressive model, this study investigates the nonlinear price transmission among tuna, salmon and hake during a food safety incident. The tuna fraud in Spain caused a histamine outbreak in 2017, which made 105 people fall ill. To evaluate the degree to which the food safety incident affected price transmission and reflected consumer awareness of the tuna fraud scandal, we have developed a communication index based on the number of Twitter posts and use its first difference to identify the increasing and decreasing regime of the development of the incident
2024-01-24T12:58:55ZJin, YanGil Roig, José MaríaUsing a two-regime threshold vector autoregressive model, this study investigates the nonlinear price transmission among tuna, salmon and hake during a food safety incident. The tuna fraud in Spain caused a histamine outbreak in 2017, which made 105 people fall ill. To evaluate the degree to which the food safety incident affected price transmission and reflected consumer awareness of the tuna fraud scandal, we have developed a communication index based on the number of Twitter posts and use its first difference to identify the increasing and decreasing regime of the development of the incidentDrastic microbial count reduction in soy milk using continuous short-wave ultraviolet treatments in a tubular annular thin film UV-C reactor
http://hdl.handle.net/2117/400114
Drastic microbial count reduction in soy milk using continuous short-wave ultraviolet treatments in a tubular annular thin film UV-C reactor
Sauceda Gálvez, Jezer Noe; Codina Torrella, Idoia; Gervilla Fernández, Ramón; Hernández Herrero, María Manuela; Roig Sagués, Artur Xavier; Martínez García, María
Vegetative cells of Listeria monocytogenes and Escherichia coli and spores of Bacillus subtilis and Aspergillus niger were inoculated in soy milk at an initial concentration of ˜5 log CFU/mL. Inoculated and control (non-inoculated) soy milk samples were submitted to three types of treatments using a tubular annular thin film short-wave ultraviolet (UV-C) reactor with 1 mm of layer thickness. Treatments applied depended on the flow rate and the number of entries to the reactor, with UV-C doses ranging from 20 to 160 J/mL. The number of entries into the reactor tube (NET) was established as the most determining parameter for the efficiency of the UV-C treatments. Conidiospores of A. niger were reported as the most resistant, followed by B. subtilis spores, while vegetative cells were the most sensible to UV-C, with Listeria monocytogenes being more sensible than Escherichia coli. Treatments of just 80 J/mL were needed to achieve a 5 log CFU/mL reduction of L. monocytogenes while 160 J/mL was necessary to achieve a similar reduction for A. niger spores
2024-01-24T11:04:57ZSauceda Gálvez, Jezer NoeCodina Torrella, IdoiaGervilla Fernández, RamónHernández Herrero, María ManuelaRoig Sagués, Artur XavierMartínez García, MaríaVegetative cells of Listeria monocytogenes and Escherichia coli and spores of Bacillus subtilis and Aspergillus niger were inoculated in soy milk at an initial concentration of ˜5 log CFU/mL. Inoculated and control (non-inoculated) soy milk samples were submitted to three types of treatments using a tubular annular thin film short-wave ultraviolet (UV-C) reactor with 1 mm of layer thickness. Treatments applied depended on the flow rate and the number of entries to the reactor, with UV-C doses ranging from 20 to 160 J/mL. The number of entries into the reactor tube (NET) was established as the most determining parameter for the efficiency of the UV-C treatments. Conidiospores of A. niger were reported as the most resistant, followed by B. subtilis spores, while vegetative cells were the most sensible to UV-C, with Listeria monocytogenes being more sensible than Escherichia coli. Treatments of just 80 J/mL were needed to achieve a 5 log CFU/mL reduction of L. monocytogenes while 160 J/mL was necessary to achieve a similar reduction for A. niger sporesTECTEX-Grupo de investigación en tecnología textil: investigación para contribuir a la transición verde y digital de la industria textil
http://hdl.handle.net/2117/399930
TECTEX-Grupo de investigación en tecnología textil: investigación para contribuir a la transición verde y digital de la industria textil
Carrera Gallissà, Enric; Algaba Joaquín, Inés María; Buscio Olivera, Valentina; Claramunt Blanes, Josep; Cano Casas, Francesc; Cayuela Marín, Diana; Ilén, Elina Emilia; Oliver Ortega, Helena; Riba Moliner, Marta; Tornero García, José Antonio; Ventura Casellas, Heura; Ardanuy Raso, Mònica
El grupo de investigación de ingeniería textil (TECTEX) INTEXTER y del Departamento de Ciencia e Ingeniería de Materiales de la Universitat Politècnica de Catalunya tiene como principal objetivo el desarrollo y optimización de nuevos materiales, procesos y tecnologías de la cadena de valor de la industria textil (desde la producción y caracterización de fibras y tejidos, procesos de tintura y acabado, hasta productos textiles). La finalidad de la actividad de nuestro grupo de investigación es reducir los impactos ambientales, aumentar la circularidad y optimizar los materiales, procesos y tecnologías textiles, así como desarrollar soluciones de alto valor añadido. Todo ello para contribuir a la creación de un sector textil más sostenible y competitivo. En particular, la investigación que llevamos a cabo en TECTEX se centra en contribuir a resolver los retos globales y las necesidades de competitividad industrial europea relacionadas con la transición ecológica y la transición digital, así como con el desarrollo de nuevas soluciones de alto valor añadido enfocadas principalmente al desarrollo de dispositivos y sistemas para aplicaciones biomédicas. En este artículo se presentarán los principales proyectos que actualmente estamos liderando desde nuestro grupo de investigación, como son los proyectos relacionados con la obtención de fibras naturales a partir de residuos agrícolas (HEMPQUAL), la obtención de colorantes naturales a partir de residuos agrícolas (OLIWASTEX), el reciclaje de residuos textiles por métodos mecánicos (RECYWASTEX), el desarrollo de materiales compuestos de cemento reforzados con fibras y estructuras textiles (RECYBUILDMAT), el electrohilado para aplicaciones biomédicas (ONCOFIBRAS y la aplicación del blockchain y trazabilidad a la industria textil (TRICK)
2024-01-22T12:40:10ZCarrera Gallissà, EnricAlgaba Joaquín, Inés MaríaBuscio Olivera, ValentinaClaramunt Blanes, JosepCano Casas, FrancescCayuela Marín, DianaIlén, Elina EmiliaOliver Ortega, HelenaRiba Moliner, MartaTornero García, José AntonioVentura Casellas, HeuraArdanuy Raso, MònicaEl grupo de investigación de ingeniería textil (TECTEX) INTEXTER y del Departamento de Ciencia e Ingeniería de Materiales de la Universitat Politècnica de Catalunya tiene como principal objetivo el desarrollo y optimización de nuevos materiales, procesos y tecnologías de la cadena de valor de la industria textil (desde la producción y caracterización de fibras y tejidos, procesos de tintura y acabado, hasta productos textiles). La finalidad de la actividad de nuestro grupo de investigación es reducir los impactos ambientales, aumentar la circularidad y optimizar los materiales, procesos y tecnologías textiles, así como desarrollar soluciones de alto valor añadido. Todo ello para contribuir a la creación de un sector textil más sostenible y competitivo. En particular, la investigación que llevamos a cabo en TECTEX se centra en contribuir a resolver los retos globales y las necesidades de competitividad industrial europea relacionadas con la transición ecológica y la transición digital, así como con el desarrollo de nuevas soluciones de alto valor añadido enfocadas principalmente al desarrollo de dispositivos y sistemas para aplicaciones biomédicas. En este artículo se presentarán los principales proyectos que actualmente estamos liderando desde nuestro grupo de investigación, como son los proyectos relacionados con la obtención de fibras naturales a partir de residuos agrícolas (HEMPQUAL), la obtención de colorantes naturales a partir de residuos agrícolas (OLIWASTEX), el reciclaje de residuos textiles por métodos mecánicos (RECYWASTEX), el desarrollo de materiales compuestos de cemento reforzados con fibras y estructuras textiles (RECYBUILDMAT), el electrohilado para aplicaciones biomédicas (ONCOFIBRAS y la aplicación del blockchain y trazabilidad a la industria textil (TRICK)Mechanical properties and durability of biobased fabric-reinforced lime composites intended for strengthening historical masonry structures
http://hdl.handle.net/2117/399925
Mechanical properties and durability of biobased fabric-reinforced lime composites intended for strengthening historical masonry structures
Rakhsh Mahpour, Ali; Ardanuy Raso, Mònica; Ventura Casellas, Heura; Rosell Amigó, Juan Ramón; Claramunt Blanes, Josep
The use of lime-based composites reinforced with fabrics made of natural fibers, is a promising solution for the strengthening of historical masonry structures owing to its moderate mechanical strength, similar color and chemical compatibility, avoiding damage on the historical structure and contributing to crack-width control. In this study, a new lime-based composite reinforced with flax nonwoven fabrics is mechanically characterized to study its reinforcement potential in terms of strength, and stress distribution. To this end, laminate plates with lime/metakaolin matrix and four to six layers of fabric reinforcement were produced and totally carbonated in a CO2 chamber. Both the mechanical (flexural and tensile) and durability (against wet-dry cycles) properties of the composite were subsequently assessed. Furthermore, Digital Image Correlation (DIC) was carried out on tensile testing to study the stress distribution. The 6-layer composites displayed the best performance (with flexural and tensile strengths of approximately 5.3 MPa and 2.5 MPa, respectively), followed by the 5-layer and the 4-layer composites. The DIC analysis revealed a higher stress distribution in the 6-layer composites, with an increased number of cracks, although having a lower severity. As for durability, a decrease of 30–45% is observed in flexural strength, and of 6–18% in tensile strength, depending on the number of reinforcing layers. SEM analysis refers to fiber/matrix debonding as the cause of this decrease. No damage has been observed on the fiber surface, which retains its reinforcing capacity. All of the composites displayed strain-hardening behavior in both the unaged and aged conditions. Study outcomes are intended to serve as the basis for the creation of a future, compatible, reliable, and sustainable system given its potential application in the historical restoration of masonry structures
2024-01-22T10:20:34ZRakhsh Mahpour, AliArdanuy Raso, MònicaVentura Casellas, HeuraRosell Amigó, Juan RamónClaramunt Blanes, JosepThe use of lime-based composites reinforced with fabrics made of natural fibers, is a promising solution for the strengthening of historical masonry structures owing to its moderate mechanical strength, similar color and chemical compatibility, avoiding damage on the historical structure and contributing to crack-width control. In this study, a new lime-based composite reinforced with flax nonwoven fabrics is mechanically characterized to study its reinforcement potential in terms of strength, and stress distribution. To this end, laminate plates with lime/metakaolin matrix and four to six layers of fabric reinforcement were produced and totally carbonated in a CO2 chamber. Both the mechanical (flexural and tensile) and durability (against wet-dry cycles) properties of the composite were subsequently assessed. Furthermore, Digital Image Correlation (DIC) was carried out on tensile testing to study the stress distribution. The 6-layer composites displayed the best performance (with flexural and tensile strengths of approximately 5.3 MPa and 2.5 MPa, respectively), followed by the 5-layer and the 4-layer composites. The DIC analysis revealed a higher stress distribution in the 6-layer composites, with an increased number of cracks, although having a lower severity. As for durability, a decrease of 30–45% is observed in flexural strength, and of 6–18% in tensile strength, depending on the number of reinforcing layers. SEM analysis refers to fiber/matrix debonding as the cause of this decrease. No damage has been observed on the fiber surface, which retains its reinforcing capacity. All of the composites displayed strain-hardening behavior in both the unaged and aged conditions. Study outcomes are intended to serve as the basis for the creation of a future, compatible, reliable, and sustainable system given its potential application in the historical restoration of masonry structuresAn opportunity for acerola pulp (Malpighia emarginata DC) valorization evaluating its performance during the block cryoconcentration by physicochemical, bioactive compounds, HPLC–ESI-MS/MS, and multi-elemental profile analysis
http://hdl.handle.net/2117/399606
An opportunity for acerola pulp (Malpighia emarginata DC) valorization evaluating its performance during the block cryoconcentration by physicochemical, bioactive compounds, HPLC–ESI-MS/MS, and multi-elemental profile analysis
Marafon, Karine; Pereira Coleho, Marina; Da Silva Haas, Isabel Cristina; Da Silva Monteiro Wanderley, Bruna Rafaela; Santos de Gois, Jefferson; Vitali, Luciano; Luna, Ardeval S.; Machado Canella, Maria Helena; Hernández Yáñez, Eduard; Dias de Mello Castanho, Renata; Prudêncio, Elane Schwinden
The present study evaluated the effect of cryoconcentration of pulp blocks of acerola (Malpighia emarginata DC). The study evaluated cryoconcentration in three stages. The cryoconcentrated samples, the ice fractions, and the initial pulp were evaluated for physicochemical composition, bioactive composition, and multielement profile. The cryoconcentrated sample obtained in the third stage of cryoconcentration showed the best results for the concentration factor, process efficiency, total soluble solids content, red color intensity, and increasing of the macro and micronutrients: Cu, Ca, S, Sr, K, Mn, Na, P, Mg, Fe. All stages presented good performance in the total soluble solids content, increase in the titratable acidity of the concentrates, and progressive increase in the intensity of the red color. Generally, higher levels of total phenolic and antioxidant activity were found for the 2nd and 3rd concentrates. The phenolic activity showed an increase of 166.90% in the 3rd stage concentrate compared to fresh pulp, and the antioxidant activity was 112.10% by the ABTS method and 131.60% by the DPPH method, both in the 3rd stage concentrate. The major individual polyphenols were Ferulic acid, Protocatechuic acid, and Taxifolin, with significant increases in the concentration of the compounds in the 2nd and 3rd stage concentrates. In addition, the contents of potentially toxic metals were below detection limits. During the cryoconcentration process, there was a decrease in the values of vitamin C content, moisture content, density, and elements Cu, Sr, and Zn.
2024-01-16T12:34:27ZMarafon, KarinePereira Coleho, MarinaDa Silva Haas, Isabel CristinaDa Silva Monteiro Wanderley, Bruna RafaelaSantos de Gois, JeffersonVitali, LucianoLuna, Ardeval S.Machado Canella, Maria HelenaHernández Yáñez, EduardDias de Mello Castanho, RenataPrudêncio, Elane SchwindenThe present study evaluated the effect of cryoconcentration of pulp blocks of acerola (Malpighia emarginata DC). The study evaluated cryoconcentration in three stages. The cryoconcentrated samples, the ice fractions, and the initial pulp were evaluated for physicochemical composition, bioactive composition, and multielement profile. The cryoconcentrated sample obtained in the third stage of cryoconcentration showed the best results for the concentration factor, process efficiency, total soluble solids content, red color intensity, and increasing of the macro and micronutrients: Cu, Ca, S, Sr, K, Mn, Na, P, Mg, Fe. All stages presented good performance in the total soluble solids content, increase in the titratable acidity of the concentrates, and progressive increase in the intensity of the red color. Generally, higher levels of total phenolic and antioxidant activity were found for the 2nd and 3rd concentrates. The phenolic activity showed an increase of 166.90% in the 3rd stage concentrate compared to fresh pulp, and the antioxidant activity was 112.10% by the ABTS method and 131.60% by the DPPH method, both in the 3rd stage concentrate. The major individual polyphenols were Ferulic acid, Protocatechuic acid, and Taxifolin, with significant increases in the concentration of the compounds in the 2nd and 3rd stage concentrates. In addition, the contents of potentially toxic metals were below detection limits. During the cryoconcentration process, there was a decrease in the values of vitamin C content, moisture content, density, and elements Cu, Sr, and Zn.Air-pinch PWM valve to regulate flow rate of hollow-cone nozzles for variable-rate sprayers
http://hdl.handle.net/2117/399472
Air-pinch PWM valve to regulate flow rate of hollow-cone nozzles for variable-rate sprayers
Zhu, Heping; Jeon, Hongyoung; Salcedo Cidoncha, Ramón; Ozkan, Erdal; Román, Carla; Gil Moya, Emilio
Electric pulse width modulation (PWM) solenoid valves are commonly used to regulate nozzle flow rates to achieve precision variable-rate spray applications. However, some pesticide formulations, such as wettable powders and adhesive additives, can potentially cause a malfunction such that the valve cannot completely shut off during flow rate modulation if spray lines are not cleaned thoroughly after spray applications. An air-pinch PWM valve was evaluated as a potential alternative to conventional PWM valves to modulate the flow rates of hollow-cone nozzles used on air-assisted orchard sprayers. With the air-pinch valve, spray mixtures only passed through a flexible tube to avoid chemicals directly contacting the moving components inside the valve chamber. The flow rate modulation was performed by pinching and releasing the tube back and forth with air-pilot PWM actions. Evaluations included the flow rate modulation capability along with droplet size distributions from three disc-core hollow-cone nozzles coupled with the PWM pinch valve and compared with a conventional electric PWM valve. Both air-pinch and electric PWM valves performed comparably in the flow rate modulation accuracy and droplet size distribution for hollow-cone nozzles operated at 414 and 827 kPa pressures across the duty cycles (DUCs) ranging from 10% to 100%, except for the air-pinch valve that could not activate at 10% DUC. The flow rates of nozzles modulated with both PWM valves at all DUCs were 5.3% greater on average than the target flow rates, while the flow rates were similar at 90% and 100% DUCs. Droplet size classifications based on ASABE Standard S-572.3 were generally consistent across DUCs ranging from 20% to 100% for the same nozzle and pressure with the air-pinch PWM valve and from 10% to 100% with the conventional electric PWM valve. The consistency of droplet sizes across DUCs and accuracy of flow rate modulations demonstrated the potential advantage of using the air-pinch PWM solenoid valve as an alternative for precision variable-rate sprayers to accurately apply different chemicals.
2024-01-15T15:35:07ZZhu, HepingJeon, HongyoungSalcedo Cidoncha, RamónOzkan, ErdalRomán, CarlaGil Moya, EmilioElectric pulse width modulation (PWM) solenoid valves are commonly used to regulate nozzle flow rates to achieve precision variable-rate spray applications. However, some pesticide formulations, such as wettable powders and adhesive additives, can potentially cause a malfunction such that the valve cannot completely shut off during flow rate modulation if spray lines are not cleaned thoroughly after spray applications. An air-pinch PWM valve was evaluated as a potential alternative to conventional PWM valves to modulate the flow rates of hollow-cone nozzles used on air-assisted orchard sprayers. With the air-pinch valve, spray mixtures only passed through a flexible tube to avoid chemicals directly contacting the moving components inside the valve chamber. The flow rate modulation was performed by pinching and releasing the tube back and forth with air-pilot PWM actions. Evaluations included the flow rate modulation capability along with droplet size distributions from three disc-core hollow-cone nozzles coupled with the PWM pinch valve and compared with a conventional electric PWM valve. Both air-pinch and electric PWM valves performed comparably in the flow rate modulation accuracy and droplet size distribution for hollow-cone nozzles operated at 414 and 827 kPa pressures across the duty cycles (DUCs) ranging from 10% to 100%, except for the air-pinch valve that could not activate at 10% DUC. The flow rates of nozzles modulated with both PWM valves at all DUCs were 5.3% greater on average than the target flow rates, while the flow rates were similar at 90% and 100% DUCs. Droplet size classifications based on ASABE Standard S-572.3 were generally consistent across DUCs ranging from 20% to 100% for the same nozzle and pressure with the air-pinch PWM valve and from 10% to 100% with the conventional electric PWM valve. The consistency of droplet sizes across DUCs and accuracy of flow rate modulations demonstrated the potential advantage of using the air-pinch PWM solenoid valve as an alternative for precision variable-rate sprayers to accurately apply different chemicals.Static and dynamic performance evaluation of a solid-state lidar for 3D object detection in greenhouse spray applications
http://hdl.handle.net/2117/399469
Static and dynamic performance evaluation of a solid-state lidar for 3D object detection in greenhouse spray applications
Zhang, Zhihong; Long, Jianing; Lai, Qinghui; Zhu, Qingmeng; He, Hao; Salcedo Cidoncha, Ramón; Yan, Tingting
An effective variable-rate spraying system for greenhouses requires accurate canopy structure parameters of plants to ensure proper pesticide dosage adjustment. While conventional laser systems integrated into spray systems can provide precise point cloud data of plants, they still present a high expense. This study examines the performance of a recently introduced, cost-effective, and high-resolution solid-state LiDAR (Intel RealSense L515) in relation to its potential for greenhouse spray applications. Additionally, a specialized point cloud acquisition algorithm was developed for this solid-state LiDAR to obtain the geometrical parameters of objects. To assess the LiDAR sensor's suitability for greenhouse spray applications, the performance of the LiDAR sensor and the algorithm was evaluated using five different sized regular-shaped cartons and three artificial plants with complex geometry. Various factors were analyzed, such as the horizontal distances between objects and the LiDAR sensor (0.5, 1.0, 1.5, 2.0, 2.5, and 3.0 m), the tilt angle of the LiDAR sensor relative to the ground (45°, 60°, and 75°), the height of the LiDAR sensor from the ground (ranging from 0.3 to 0.8 m with 0.5 m distance intervals), and the forward speed of the LiDAR sensor (0.1, 0.3, 0.6, and 0.9 m s-1). The findings revealed that the optimal detection distance for this LiDAR sensor is 1.0 m. Increasing or decreasing the detection distance of the object relative to the LiDAR sensor diminished the measurement accuracy. The accuracy of the derived geometrical variables was affected by the height and tilt angle of the LiDAR sensor. Nevertheless, the geometrical parameters obtained from the solid-state LiDAR showed a favorable correspondence with the results of manual measurements. The highest root mean square error (RMSE) and coefficient of variation (CV) for the overall test were 14.3 mm and 14.3% in the X (length) direction, 14.3 mm and 14.3% in the Y (width) direction, and 10.8 mm and 10.8% in the Z (height) direction, respectively. The contour Edge Similarity Score for objects measured using the solid-state LiDAR and images obtained with an RGB camera exceeded 0.90. These findings suggest that the proposed solid-state LiDAR and the specifically designed algorithm could be effectively adapted to acquire the geometrical parameters of objects and to develop precise variable-rate spraying systems for greenhouse applications.
2024-01-15T15:10:42ZZhang, ZhihongLong, JianingLai, QinghuiZhu, QingmengHe, HaoSalcedo Cidoncha, RamónYan, TingtingAn effective variable-rate spraying system for greenhouses requires accurate canopy structure parameters of plants to ensure proper pesticide dosage adjustment. While conventional laser systems integrated into spray systems can provide precise point cloud data of plants, they still present a high expense. This study examines the performance of a recently introduced, cost-effective, and high-resolution solid-state LiDAR (Intel RealSense L515) in relation to its potential for greenhouse spray applications. Additionally, a specialized point cloud acquisition algorithm was developed for this solid-state LiDAR to obtain the geometrical parameters of objects. To assess the LiDAR sensor's suitability for greenhouse spray applications, the performance of the LiDAR sensor and the algorithm was evaluated using five different sized regular-shaped cartons and three artificial plants with complex geometry. Various factors were analyzed, such as the horizontal distances between objects and the LiDAR sensor (0.5, 1.0, 1.5, 2.0, 2.5, and 3.0 m), the tilt angle of the LiDAR sensor relative to the ground (45°, 60°, and 75°), the height of the LiDAR sensor from the ground (ranging from 0.3 to 0.8 m with 0.5 m distance intervals), and the forward speed of the LiDAR sensor (0.1, 0.3, 0.6, and 0.9 m s-1). The findings revealed that the optimal detection distance for this LiDAR sensor is 1.0 m. Increasing or decreasing the detection distance of the object relative to the LiDAR sensor diminished the measurement accuracy. The accuracy of the derived geometrical variables was affected by the height and tilt angle of the LiDAR sensor. Nevertheless, the geometrical parameters obtained from the solid-state LiDAR showed a favorable correspondence with the results of manual measurements. The highest root mean square error (RMSE) and coefficient of variation (CV) for the overall test were 14.3 mm and 14.3% in the X (length) direction, 14.3 mm and 14.3% in the Y (width) direction, and 10.8 mm and 10.8% in the Z (height) direction, respectively. The contour Edge Similarity Score for objects measured using the solid-state LiDAR and images obtained with an RGB camera exceeded 0.90. These findings suggest that the proposed solid-state LiDAR and the specifically designed algorithm could be effectively adapted to acquire the geometrical parameters of objects and to develop precise variable-rate spraying systems for greenhouse applications.Biopesticides as alternatives to reduce the use of copper in Spanish and Portuguese viticulture: Main trends in adoption
http://hdl.handle.net/2117/399388
Biopesticides as alternatives to reduce the use of copper in Spanish and Portuguese viticulture: Main trends in adoption
Ortega Rioja, Paula; Salcedo Cidoncha, Ramón; Sánchez Sánchez, Elena; Gil Moya, Emilio
The traditional use of copper as a fungicide in vineyards has raised concerns among authorities as it increases environmental pollution. As a result, new regulations have been enacted to reduce the use of plant protection products while encouraging the use of biological pesticides, which are less harmful to the environment. In this study, we surveyed two of the most relevant countries in terms of vine cultivation: Spain and Portugal. The objective of this study was to analyse the factors influencing the use of copper-based fungicides and their biological alternatives to provide a framework for state-of-the-art downy mildew control. This has led to some forward-thinking on the applicability of EU objectives. A probabilistic LogiT model was used to observe the field and exploitation variables that influenced winegrowers’ use of biopesticides. Given its great reliance on copper, it can be concluded that copper is still a necessary product for viticulture. Moreover, because the use of synthetic products is prohibited in organic vineyards, more copper treatments are carried out. Although the intention to use biopesticides exists, this did not result in actual use. The most influential factor in the probability of biopesticide use is knowledge of the legislation; however, it is also important to have watercourses near the field and to have the necessary technology. These results are relevant for formulating recommendations to ensure that all information reaches small farmers, as this would be key to more sustainable agriculture in Europe.
2024-01-15T13:01:10ZOrtega Rioja, PaulaSalcedo Cidoncha, RamónSánchez Sánchez, ElenaGil Moya, EmilioThe traditional use of copper as a fungicide in vineyards has raised concerns among authorities as it increases environmental pollution. As a result, new regulations have been enacted to reduce the use of plant protection products while encouraging the use of biological pesticides, which are less harmful to the environment. In this study, we surveyed two of the most relevant countries in terms of vine cultivation: Spain and Portugal. The objective of this study was to analyse the factors influencing the use of copper-based fungicides and their biological alternatives to provide a framework for state-of-the-art downy mildew control. This has led to some forward-thinking on the applicability of EU objectives. A probabilistic LogiT model was used to observe the field and exploitation variables that influenced winegrowers’ use of biopesticides. Given its great reliance on copper, it can be concluded that copper is still a necessary product for viticulture. Moreover, because the use of synthetic products is prohibited in organic vineyards, more copper treatments are carried out. Although the intention to use biopesticides exists, this did not result in actual use. The most influential factor in the probability of biopesticide use is knowledge of the legislation; however, it is also important to have watercourses near the field and to have the necessary technology. These results are relevant for formulating recommendations to ensure that all information reaches small farmers, as this would be key to more sustainable agriculture in Europe.Design, implementation and validation of a sensor-based precise airblast sprayer to improve pesticide applications in orchards
http://hdl.handle.net/2117/399382
Design, implementation and validation of a sensor-based precise airblast sprayer to improve pesticide applications in orchards
Salas i Barenys, Bernat; Salcedo Cidoncha, Ramón; García Ruiz, Francisco José; Gil Moya, Emilio
An orchard sprayer prototype running a variable-rate algorithm to adapt the spray volume to the
canopy characteristics (dimensions, shape and leaf density) in real-time was designed and
implemented. The developed machine was able to modify the application rate by using an
algorithm based on the tree row volume (TRV), in combination with a newly coefficient defined
as Density Factor (Df). Variations in the canopy characteristics along the row crop were
electronically measured using six ultrasonic sensors (three per sprayer side)
2024-01-15T12:41:10ZSalas i Barenys, BernatSalcedo Cidoncha, RamónGarcía Ruiz, Francisco JoséGil Moya, EmilioAn orchard sprayer prototype running a variable-rate algorithm to adapt the spray volume to the
canopy characteristics (dimensions, shape and leaf density) in real-time was designed and
implemented. The developed machine was able to modify the application rate by using an
algorithm based on the tree row volume (TRV), in combination with a newly coefficient defined
as Density Factor (Df). Variations in the canopy characteristics along the row crop were
electronically measured using six ultrasonic sensors (three per sprayer side)