An Active helideck testbed for floating structures based on a Stewart-Gough platform

A parallel robot testbed based on Stewart-Gough platform called Active-helideck is designed, developed and tested as a helicopter floating helideck. The objective of this testbed is to show the advantages of helicopters that use an active helideck upon landing on and taking off from ships or from offshore structures. Active-helideck compensates simulated movements of a ship at sea. The main goal of this study is to maintain the robot’s end effector (helideck) in a quasi-static position in accordance to an absolute inertial frame. Compensation is carried out through the coordinate action of its six prismatic actuators in function of an inertial measurement unit. Moreover, the simulation of the sea movement is done by a parallel robot called ship platform with three degrees of freedom. The ship platform is built with a vertical oscillation along the z axis, i.e. heave, and rotates on remaining axes, i.e. roll and pitch. Active helideck is able to compensate simulated movements by considering the ship as an inertial frame as observed in the experiment

On The Effects of The Variations In Network Characteristics In Cyber Physical Systems

The popular robotic simulator, Gazebo, lacks the feature of simulating the effects of control latency that would make it a fully-fledged cyber-physical system (CPS) simulator. The CPS that we address to measure is a robotic arm (UR5) controlled remotely with velocity commands. The main goal is to measure Quality of Control (QoC) related KPIs during various network conditions in a simulated environment. We propose a Gazebo plugin to make the above measurement feasible by making Gazebo capable to delay internal control and status messages and also to interface with external network simulators to derive even more advanced network effects. Our preliminary evaluation shows that there is certainly an effect on the behavior of the robotic arm with the introduced network latency in line with our expectations, but a more detailed further study is needed.Comment: In Proc., 31st European Simulation and Modelling Conference, Oct 25-27, 201

Multibody Dynamics Model of a Human Hand for Haptics Interaction

In this paper we propose a strategy for modelling a human hand for Haptics interaction. The strategy consists in a parallel computing architecture that calculates the dynamics of a hand; this is accomplished by computing the dynamics of each finger in a parallel manner. In this approach multiple threads (e.g. haptics thread, graphics thread, collision detection thread, etc.) run concurrently and therefore we developed a synchronization mechanism for data exchange. We describe in detail the elements of the developed software

Seroprevalencia de marcadores para infecciones transmisibles por transfusión en donantes de un hospital de referencia nacional de Paraguay, 2016

El uso de los componentes sanguíneos se ha vuelto muy importante para el manejo clínico de diversas patologías, sin embargo, no está exento de complicaciones, una de ellas son las infecciones transmisibles por transfusión (ITT). En las últimas décadas el riesgo de ITT se ha reducido eficazmente gracias a la pesquisa de marcadores serológicos en los donantes. El objetivo del trabajo fue determinar la seroprevalencia de marcadores para infecciones transmitidas por transfusión en donantes de un Hospital de Referencia Nacional de Paraguay durante el año 2016. Este fue un estudio observacional descriptivo de corte transversal. Fueron incluidos todos los pacientes registrados como donantes voluntarios y de reposición que acudieron al hospital durante los meses de enero a diciembre del 2016. La población base estuvo conformado por 21.428 donantes, de los cuales 10.05% presentó pruebas serológicas reactivas. La mediana de edad fue de 32 años, el rango etario más frecuente fue entre 25 a 29 años, el sexo masculino tuvo una frecuencia de 66.89% en los donantes, y el 56.69% de los donantes contaba con seguro médico. El 0.75% fueron donantes voluntarios mientras que el marcador más prevalente fue para sífilis con 5.36%. En relación al Informe del Estado Global de la seguridad de la sangre y su disponibilidad publicado por la Organización Mundial de la Salud (OMS) en el año 2012, los resultados son coherentes con las seroprevalencias dadas por el mismo

La gestión de las microempresas del cacao y sus efectos en el comportamiento de las exportaciones en la provincia de Santo Domingo de los Tsáchillas – Ecuador

Aborda la gestión de las microempresas del cacao y su efecto en el comportamiento de las exportaciones en la provincia de Santo Domingo de los Tsáchilas en Ecuador. El estudio es de tipo descriptivo, transversal, con enfoque cualitativo y cuantitativo en el que se aplicaron encuestas a una muestra de 95 cacaoteros de un universo de 465 agricultores; y se realizaron 30 observaciones a fincas cacaoteras mediante una lista de chequeo. Los resultados mostraron que la mayor parte de los cacaoteros se caracteriza, una gestión administrativa y operativa informal, en la que prima el saber ancestral, y que han recibido poco apoyo en transferencia técnica y de conocimiento por parte del Estado. Las exportaciones de cacao desde esta provincia se ven limitadas debido a que los cacaoteros no alcanzan los estándares de calidad y requisitos mínimos necesarios para la exportación. Se encontró una correlación de 0,876 (Pearson) entre el nivel de gestión administrativa y operativa y la participación en exportaciones. Como propuesta se formuló una serie de lineamientos que funcionarían a través del apoyo estatal, sustentados en mejorar la capacitación, conocimiento y tecnificación; además de impulsar procesos de asociatividad para la conformación de gremios que fortalezcan su poder de negociación, abrir puertas al acceso a créditos y apoyo técnico.Tesi

Deteção de incidentes marítimos nas zonas costeiras

O amplo espaço marítimo Português p ermite o desenvolvimento de diferentes atividades, tais como o comércio internacional, a p esca e o turismo. Porém, a o corrência de incidentes marítimos p o de aumentar e ameaçar a p opulação. A p oluição das águas, o aparecimento de caravelas-p ortuguesas nas praias, os acidentes com embarcaçõ es e a queda de arribas, constituem algu ns desses incidentes. Como tal, torna-se imp erativo a vigilância e monitorização destas ameaças p or parte das autoridades marítimas. Assim, de forma a auxiliar as autoridades marítimas na vigilância e monitorização destas ameaças, a presente dissertação prop õ e u m sistema de ap oio à decisão de baixo custo comp osto p or 4 comp onentes: veículo aéreo não-tripulado, sensor, aprendizagem automática e interface gráfica. Este sistema tem como ob jetivo detetar, identificar e classificar in cidentes marítimos nas zonas costeiras p ortuguesas em temp o real contribuindo para uma melhor eficácia das autoridades marítimas. Para isto, foi testado o uso de um veículo aéreo não-tripulado, de p equenas dimensõ es e baixo custo, com sensor ótico na recolh a de imagens de manch as de hidro carb onetos na água em ambiente simulado. Foram aplicadas fu ncionalidades de aprendizagem automática do software Orange Data Mining To ol para treino e teste do reconhecimento e classifi cação das imagens com manch as de hidro carb onetos na água recolhidas. Posteriormente, foi criado um protótip o de uma interface gráfico de uma aplicação móvel com recurso ao software Balsamiq. Este oferece a p ossi bilidade de planear e controlar o vo o do drone e a receção de alertas de in ci dentes marítimos e foi validado através do critério System Usability Scale. Os resultados obtidos em ambiente simul ad o su gerem que o drone, o sensor ótico e a aprendizagem automática p o derão constituir a solução d e um sistema de ap oio à deteção de incidentes marítimos. Desta forma, este estudo contribui para o auxílio das autoridades marítimas na deteção, identificação e classificação de incidentes marítimos nas zonas costeiras p ortuguesas.The ample Portuguese maritime space allows the development of different activities, such as international trade, fishing and touri sm. However, the o ccurrence of maritime in cidents can increase and threaten the p opulation. Water p ollution, the app earance of Portuguese caravels on b eaches, accidents with b oats and falling cliffs, are s ome of these incidents. As su ch, it b ecomes imp erative for maritime authorities to b e vigilant and monitor these threats. Therefore, in order to assist the maritime authorities in the surveillance and monitoring of these threats, this dissertation prop oses a low cost decision supp ort system comp osed of 4 comp onents: unmanned aerial veh icle, sensor, automatic learning an d graphic interface. This system aims to detect, identify and classify maritime incidents in Portuguese coastal areas in real time, contributing to a b etter effectiveness of maritime auth ori ties. For this, it was tested the use of an unmanned aerial vehicle, of small dimensions and low cost, with optical sensor in the collection of images of hydro carb on stains in the water in a simulated environment. The Orange Data Mining To ol software’s automatic learning features were applied for training and testing the recognition and classification of the images of hydro carb on stains in the water collected. Subsequently, a prototyp e of a graphic interface for a mobile application was created using the Balsamiq software. This offers the p ossibility to plan an d control the drone’s flight and th e reception of maritime incident alerts and was validated through the System Usability Scale criteria. The results obtained in a simulated environment suggest that the drone, the optical sensor and the automatic learning could constitute the solution of a system to supp ort the d etection of maritime i ncidents. Thus, this study contributes to the assistance of maritime authorities i n the detection, identification and classification of maritime incidents in Portuguese coastal areas

A Proactive Adaptation Framework for Composite Web Services

Service orientation is a design paradigm consisting of a set of principles governed by a service-oriented architecture (SOA) to support the creation of software systems as a composition of interoperable services. The ability to effectively compose services is not a trivial task due to the dynamic nature of the execution environment of service compositions. In this context, dynamic service selection and composition is a critical requirement and one of the major research challenges for service-based systems. This research investigates the identification, detection and prediction of the need for adaptation as well as ways to autonomously reconfigure the service composition during its execution time in order to improve service reliability and conformance with systems requirements and policies. We propose a framework for proactive adaptation of service compositions that extends current approaches for dynamic service composition by proactively and individually identifying the need for adaptation for each parallel running instance of service composition while avoiding unnecessary changes and distributing load request among different service operations when necessary. Our framework has been tested and validated using different prototypes implemented in both simulated and real environments. The results were favourable with the research objectives and indicates a major gain in the use of the proposed proactive techniques in the execution and adaptation of web service compositions