32 research outputs found
Manejo del racimo y los retoños para rendimientos rentables y frutos de alta calidad en guineos (Musa acuminata, AAA)
Two long-term banana experiments were conducted to determine the effect of bunch bagging, removal of lower hands, and sucker management on fruit and bunch characteristics and total yield. Bunches covered with either Dursban-treated or untreated perforated polyethylene bags yielded 10,539 kg/ha more than the uncovered ones during a 40-month production period. Considering the price that quality bananas demand at the farm gate and the cost of bagging (materials and labor), this practice represents a net profit of 3,329.25/ha. La remoción de las tres manos inferiores del racimo inmaduro redujo significativamente el peso medio final de los racimos y el rendimiento total. Sin embargo, el eliminar manos y el enfundar los racimos aumentaron substancialmente el tamaño y el peso de las frutas individuales en la mano distal, con lo que mejoró la calidad de los frutos. Ambas prácticas, además, acortaron el tiempo entre la floración y la cosecha. La selección de un hijuelo de "lanza" vigoroso inmediatamente después de la siembra seguido de la poda continua de otros hijuelos competidores produjo el mayor rendimiento equivalente a 183,744 kg/ha de frutos
Development of an autonomous mobile towing vehicle for logistic tasks
Frequently carrying high loads and performing repetitive
tasks compromises the ergonomics of individuals, a recurrent scenario
in hospital environments. In this paper, we design a logistic planner of
a fleet of autonomous mobile robots for the automation of transporting
trolleys around the hospital, which is independent of the space configuration,
and robust to loss of network and deadlocks. Our robotic solution
has an innovative gripping system capable of grasping and pulling nonmodified
standard trolleys just by coupling a plate. Robots are able to
navigate autonomously, to avoid obstacles assuring the safety of operators,
to identify and dock a trolley, to access charging stations and
elevators, and to communicate with the latter. An interface was built
allowing users to command the robots through a web server. It is shown
how the proposed methodology behaves in experiments conducted at the
Faculty of Engineering of the University of Porta and Braga's Hospital.This work is financed by the ERDF - European Regional
Development Fund through the Operational Programme for Competitiveness and Internationalisation-
COMPETE 2020 Programme, and by National Funds through the Portuguese
funding agency, FCT-Fundação para a Ciência e a Tecnologia, within project
SAICTPAC/0034/2015 - POCI-01- 0145-FEDER-016418.
Authors would like to acknowledge to Trivalor, Itau and Gertal for the support of
the project RDH.info:eu-repo/semantics/publishedVersio
Robust mobile robot localization based on a security laser: An industry case study
This paper aims to address a mobile robot localization system that avoids using a dedicated laser scanner, making it possible to reduce implementation costs and the robot's size. The system has enough precision and robustness to meet the requirements of industrial environments. Design/methodology/approach - Using an algorithm for artificial beacon detection combined with a Kalman Filter and an outlier rejection method, it was possible to enhance the precision and robustness of the overall localization system. Findings - Usually, industrial automatic guide vehicles feature two kinds of lasers: one for navigation placed on top of the robot and another for obstacle detection (security lasers). Recently, security lasers extended their output data with obstacle distance (contours) and reflectivity. These new features made it possible to develop a novel localization system based on a security laser. Research limitations/implications - Once the proposed methodology is completely validated, in the future, a scheme for global localization and failure detection should be addressed. Practical implications - This paper presents a comparison between the presented approach and a commercial localization system for industry. The proposed algorithms were tested in an industrial application under realistic working conditions. Social implications - The presented methodology represents a gain in the effective cost of the mobile robot platform, as it discards the need for a dedicated laser for localization purposes. Originality/value - This paper presents a novel approach that benefits from the presence of a security laser on mobile robots (mandatory sensor when considering industrial applications), using it simultaneously with other sensors, not only to guarantee safety conditions during operation but also to locate the robot in the environment. This paper is also valuable because of the comparison made with a commercialized system, as well as the tests conducted in real industrial environments, which prove that the approach presented is suitable for working under these demanding conditions.Project "TEC4Growth" - Pervasive Intelligence, Enhancers and Proofs of Concept with Industrial Impact/NORTE-01-0145-FEDER-000020" is fnanced by the North Portugal Regional Operational Programme (NORTE 2020), under the PORTUGAL 2020 Partnership Agreement, and through the European Regional Development Fund (ERDF).info:eu-repo/semantics/publishedVersio
Autonomous robot navigation for automotive assembly task: an industry use-case
Automobile industry faces one of the most flexible productivity
caused by the number of customized models variants due to the
buyers needs. This fact requires the production system to introduce flexible,
adaptable and cooperative with humans solutions. In the present
work, a panel that should be mounted inside a van is addressed. For that
purpose, a mobile manipulator is suggested that could share the same
space with workers helping each other. This paper presents the navigation
system for the robot that enters the van from the rear door after
a ramp, operates and exits. The localization system is based on 3DOF
methodologies that allow the robot to operate autonomously. Real tests
scenarios prove the precision and repeatability of the navigation system
outside, inside and during the ramp access of the van.This work is financed by the ERDF- European Regional Development
Fund through the Operational Programme for Competitiveness and Internationalisation-
COMPETE 2020 Programme, and by National Funds through the Portuguese
funding agency, FCT- Fundação para a Ciência ea Tecnologia, within project
SAICTPAC/0034/2015 - POCI-01- 0145-FEDER-016418.info:eu-repo/semantics/publishedVersio
2D cloud template matching - a comparison between iterative closest point and perfect match
Self-localization of mobile robots in the environment is one of the most fundamental problems in the robotics field. It is a complex and challenging problem due to the high requirements of autonomous mobile vehicles, particularly with regard to algorithms accuracy, robustness and computational efficiency. In this paper we present the comparison of two of the most used map-matching algorithm, which are the Iterative Closest Point and the Perfect Match. This category of algorithms are normally applied in localization based on natural landmarks. They were compared using an extensive collection of metrics, such as accuracy, computational efficiency, convergence speed, maximum admissible initialization error and robustness to outliers in the robots sensors data. The test results were performed in both simulated and real world environments.info:eu-repo/semantics/publishedVersio
Austrolebias luzardoi (Cyprinodontiformes: Rivulidae), una especie nueva de pez anual de la cuenca del rÃo Cuareim, República Oriental del Uruguay
Austrolebias luzardoi sp. n. is described from a temporary pool of the middle section of Cuareim river basin, Departamento de Artigas, northern Uruguay. The new taxon is considered as a member of a group of species morphologically similar, defined by a short predorsal distance, the presence of light dots concentrated in the subdistal area of the dorsal fin, the absence of dark vertical stripes in the body sides of males, and by the presence of differentiated spots in the posterior portion of the caudal peduncle in females. This combination of characters includes the following species A. affinis (Amato, 1986), A. cyaneus (Amato, 1987) and A. periodicus (Costa, 1999). Austrolebias luzardoi sp. n. is distinguished from these species by the color pattern of male body, the dorsal profile of the head, the lowest height of body in relation to its standard length, and the inclination of the suborbital band that is vertical or displaced forward.Austrolebias luzardoi sp. n., se describe de charcos temporales del sector medio de la cuenca del rÃo Cuareim, Departamento de Artigas, al norte de la República Oriental del Uruguay. Este nuevo taxon se considera incluido en un grupo de especies morfológicamente similar, definido porque los machos tienen distancia predorsal corta, puntos claros concentrados en la zona subdistal de la aleta dorsal, ausencia de bandas verticales oscuras en los costados del cuerpo del macho y manchas diferenciadas en la porción posterior del pedúnculo caudal de las hembras. Esta combinación de caracteres incluye a las especies A. affinis (Amato, 1986), A. cyaneus (Amato, 1987) y A. periodicus (Costa, 1999). Esta nueva especie, se distingue de éstas por el patrón de color del cuerpo de los machos, por el perfil dorsal de la cabeza, por la altura del cuerpo mas baja en relación a la longitud estándar y por la inclinación de la banda suborbital que se encuentra vertical o desplazada hacia adelante
EVALUATION OF N-RATIO IN SELECTING PATIENTS FOR ADJUVANT CHEMORADIOTHERAPY AFTER D2-GASTRECTOMY
Ovinocultura do Rio Grande do Sul: descrição do sistema produtivo e dos principais aspectos sanitários e reprodutivos
Dosis, intervalos de aplicación y rotación de cuatro plaguicidas granulados, registrados para el control de nematodos y el picudo negro (Cosmopolites sordidus Germar) en plátano
The efficacy of the nematicide-insecticides aldicarb, carbofuran, ethoprop and phenamiphos was studied in plantain using recommended and lower label rates, shorter application intervals and rotation. These compounds were effective in reducing Radopholus similis and Pratylenchus coffeae populations when lower than recommended rates were applied at the shortened interval of four months or when the chemicals were rotated. Except for ethoprop, these compounds were also effective in controlling the corm-weevil when applied at below recommended label rates and intervals. However, the insecticide efficacy of phenamiphos and the rotation of aldicarb, phenamiphos and carbofuran was particularly high when applied at planting time and every six months thereafter. Yield components were not significantly affected by the various nematicide-insecticide treatments in the plant crop.Se estudió la eficacia de los plaguicidas granulados aldicarb, carbofuran, etoprop y fenamifos en plátano, usando las dosis recomendadas en la etiqueta del producto y dosis e intervalos de aplicación más bajos que los recomendados. También, se probaron estos plaguicidas en rotación. Todos los compuestos fueron efectivos en reducir las poblaciones de Radopholus similis y Pratylenchus coffeae cuando se aplicaron en dosis más bajas que las recomendadas en la etiqueta y a intervalos de cuatro meses, o cuando se aplicaron en rotación Excepto por etoprop, los demás compuestos fueron efectivos en reducir el daño causado por el picudo negro, cuando se aplicaron en dosis más bajas y a intervalos más cortos que lo recomendado en la etiqueta, o en rotación. Sin embargo, los tratamientos con mayor eficacia como insecticidas fueron fenamifos y la rotación de aldicarb, fenamifos y carbofuran aplicados a la siembra y a intervalos de seis meses. Ninguno de los tratamientos afectó significativamente los componentes de rendimiento en la cosecha de plantilla