770 research outputs found
Design of Nonoverconstrained Energy-Efficient Multi-Axis Servo Presses for Deep-Drawing Applications
No full textServo-actuated presses may provide maximum pressing force at any ram position in the same manner that hydraulic presses do, while offering several benefits in terms of precision, energy-conversion efficiency, and simplicity, due to their lack of hydraulic circuitry and oil. Several press builders have developed servo-actuated presses; however, issues relating to overconstrained multi-axis architecture have been disregarded. This study proposes an innovative method to avoid overconstrained architectures in multi-axis presses, by implementing a family of modular parallel mechanisms that connect multiple servo-axes to the press ram. Parallel mechanisms, which can be applied in several fields of robotics and industrial automation, exhibit important benefits for the application at hand, including high-load capacity, stiffness, and compactness. A biaxial industrial servo press prototype with a nonoverconstrained and modular architecture was built and presented as a proof of concept. Each axis comprises a servomotor, a gearbox reducer, and a ball-screw transmission. It is shown that such a press may be constructed from commercially available components, achieving high energy efficiency and high press force with relatively simple construction. A direct comparison with an equivalent hydraulic-press model is carried out, thus highlighting the servo press energy efficiency
Optimal selection of the motor-reducer unit in servo-controlled machinery: A continuous approach
No full textThis papers deals with the optimal selection of motors and reducers in servo-controlled machines. A model of an electromechanical servo-axis is developed, which allows electrical and mechanical losses to be evaluated. The model is based on data that can be extracted from commercial catalogs, thus requiring no experimental characterization. Then, a novel optimal selection procedure is presented, called continuous optimization, based on the extension of a discrete commercial catalog to a continuous one, by means of data fitting on the electromechanical parameters that influence the motor and reducer operation. A non-linear constrained optimization problem is solved in order to find the optimal motor-reducer unit with respect to a variety of objective functions, such as motor size, overall energetic efficiency, total mass, etc
Towards a deep learning based ASR system for users with dysarthria
No full textIn this paper, we investigate the benefits of deep learning approaches for the development of personalized assistive technology solutions for users with dysarthria, a speech disorder that leads to low intelligibility of users’ speaking. It prevents these people from using automatic speech recognition (ASR) solutions on computers and mobile devices. In order to address these issue, our effort is to leverage convolutional neural networks toward a speaker dependent ASR software solution intended for users with dysarthria, which can be trained according to particular user’s needs and preferences
A multi-axis deep drawing servo press with non-overconstrained architecture
No full textServo actuated presses can provide maximum pressing force at any slide position in the same manner that hydraulic presses do, while offering several benefits in terms of precision, energy conversion efficiency and simplicity due to their lack of hydraulic circuitry and oil. Several press builders have developed electric-spindle actuated presses; however, issues relating to multi-axis architecture have been neglected. The present study proposes an innovative method of avoiding overconstrained architecture by implementing a kinematic mechanism that connects multiple servo axes to one slide. Servo axis design is developed by creating a dynamic model of a kinematic chain composed of a servomotor, gearbox reducer and ball screw transmission. A study of a biaxial industrial servo press prototype with non-overconstrained architecture, currently under construction, is presented as proof of concept. It is shown that such a non-overconstrained multiaxis press can be constructed from commercially available components, achieving high energy efficiency at high load with relatively simple construction
Sirio, Orione and Pan: an Integrated Web System for Ontology-based Video Search and Annotation
No full textIn this technical demonstration we show an integrated web system for video search and annotation based on ontologies. The system is composed by three components: the Orione ontology-based search engine, the Sirio\footnote{Sirio was the hound of Orione. It was a dog so swift that no prey could escape it.} search interface, and the Pan web-based video annotation tool. The system is currently being developed within the EU IM3I project. The goal of the system is to provide an integrated environment for video annotation and retrieval of videos, for both technical and non-technical users. In fact, the search engine has different interfaces that permit different query modalities: free-text, natural language, graphical composition of concepts using Boolean and temporal relations and query by visual example. In addition, the ontology structure is exploited to encode semantic relations between concepts permitting, for example, to expand queries to synonyms and concept specializations. The annotation tool can be used to create ground-truth annotations to train automatic annotations systems, or to complement the results of automatic annotation, e.g. adding geolocalized information
Web-based Semantic Browsing of Video Collections using Multimedia Ontologies
No full textIn this technical demonstration we present a novel web-based tool that allows a user friendly semantic browsing of video collections, based on ontologies, concepts, concept relations and concept clouds. The system is developed as a Rich Internet Application (RIA) to achieve a fast responsiveness and ease of use that can not be obtained by other web application paradigms, and uses streaming to access and inspect the videos. Users can also use the tool to browse the content of social and media sharing sites like YouTube, Flickr and Twitter, accessing these external resources through the ontologies used in the system. The tool has won the second prize in the Adobe YouGC contest, in the RIA category
AI Techniques for Near Real-Time Monitoring of Contaminants in Coastal Waters on Board Future sat-2 Mission
No full textDifferently from conventional procedures, the proposed solution advocates for a groundbreaking paradigm in water quality monitoring through the integration of satellite Remote Sensing data, Artificial Intelligence techniques, and onboard processing. While conventional procedures present several drawbacks mainly related to late intervention capabilities, the objective of what proposed is to offer nearly real-time detection of contaminants in coastal waters addressing a significant gap in the existing literature and allowing fast alerts and intervention. In fact, the expected outcomes include substantial advancements in environmental monitoring, public health protection, and resource conservation. Namely, the specific focus of our study is on the estimation of Turbidity and pH parameters, for their implications on human and aquatic health. Nevertheless, the designed framework can be extended to include other parameters of interest in the water environment and beyond. Originating from our participation in the European Space Agency OrbitalAI Challenge, this article describes the distinctive opportunities and issues for the contaminants' monitoring on the Φsat-2 mission. The specific characteristics of this mission, with the tools made available, will be presented, with the methodology proposed by the authors for the onboard monitoring of water contaminants in near real-time. Preliminary promising results are presented, along with an introduction to ongoing and future work
Fluctuaciones de las variables físicas y químicas de los ríos Salí, Vipos y Tapia (Tucumán, Argentina)
No full textMartínez De Marco, Silvia N.; Beatriz C. Tracanna; María A. Barrionuevo; María G. Navarro; Gladys S. Meoni & Adriana P. Chaile. “Fluctuaciones de las variables físicas y químicas de los ríos Salí, Vipos y Tapia (Tucumán, Argentina)”. Lilloa 44 (1-2). En esta contribución se analizaron 20 parámetros físicos y químicos de los ríos Salí, Tapia y Vipos efectuándose muestreos mensuales desde marzo de 1998 a marzo de 1999. Los ríos mostraron diferentes composiciones iónicas, determinándose los siguientes tipos de aguas: bicarbonatadas / sulfatadas-sódicas / cálcicas; bicarbonatadas cálcicas-sódicas; sulfatadas cálcicas y cloruradas y/o sulfatadas sódicas. El pH varió entre 6,8 y 8,6. De acuerdo a la conductividad la mineralización fluctuó desde media en el río Vipos hasta excesiva en el Tapia. El promedio del oxígeno disuelto fue, en general, de 8 mgL-1, excepto para el emisario Salí en diciembre/98 y febrero/99 con registros a 20 mgL-1). Los valores máximos de manganeso oscilaron entre 74,3 - 426,4 µgL-1 en el río Salí emisario para agosto, octubre, diciembre de 1998 y enero de 1999 y en los ríos Tapia y tributario Salí en marzo/98 con 63,7 y 85,3 µgL-1, respectivamente. Entre los compuestos organoclorados sobresalieron metoxicloro y lindano con concentraciones que no superaron los límites establecidos para el agua de consumo.
(*) Trabajo subsidiado por el Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET). Proyecto PIP 0871/98; Consejo de Investigaciones de la Universidad Nacional de Tucumán (CIUNT) Proyectos 26/G128 y 26/G229
Tag Suggestion and Localization in User-Generated Videos Based on Social Knowledge
No full textNowadays, almost any web site that provides means for sharing user-generated multimedia content, like Flickr, Facebook, YouTube and Vimeo, has tagging functionalities to let users annotate the material that they want to share. The tags are then used to retrieve the uploaded content, and to ease browsing and exploration of these collections, e.g. using tag clouds. However, while tagging a single image is straightforward, and sites like Flickr and Facebook allow also to tag easily portions of the uploaded photos, tagging a video sequence is more cumbersome, so that users just tend to tag the overall content of a video. Moreover, the tagging process is completely manual, and often users tend to spend as few time as possible to annotate the material, resulting in a sparse annotation of the visual content. A semi-automatic process, that helps the users to tag a video sequence would improve the quality of annotations and thus the overall user experience. While research on image tagging has received a considerable attention in the latest years, there are still very few works that address the problem of automatically assigning tags to videos, locating them temporally within the video sequence. In this paper we present a system for video tag suggestion and temporal localization based on collective knowledge and visual similarity of frames. The algorithm suggests new tags that can be associated to a given keyframe exploiting the tags associated to videos and images uploaded to social sites like YouTube and Flickr and visual features
Progetto DUSE: analisi preliminare dei comportamenti sedentari, delle abitudini alimentari e del benessere psicologico negli adolescenti italiani
No full textIntroduzione
Secondo i dati dell’Organizzazione Mondiale della Sanità, negli ultimi decenni, l’obesità ha registrato un aumento significativo in Europa: attualmente, quasi il 60% degli adulti e circa un terzo dei bambini (29% dei maschi e 27% delle femmine) presenta sovrappeso o obesità. L’adolescenza costituisce una fase particolarmente delicata dal punto di vista nutrizionale, durante la quale è fondamentale promuovere strategie integrate di prevenzione, monitoraggio e educazione. In questo contesto si inserisce il progetto europeo DUSE, finalizzato allo sviluppo di interventi educativi innovativi volti a sensibilizzare adolescenti sull’importanza di adottare e mantenere stili di vita sani, essenziali per la prevenzione delle malattie non trasmissibili, tra cui il diabete di tipo 2. L’obiettivo dello studio è di analizzare le interazioni tra comportamenti sedentari, attività fisica, abitudini alimentari e benessere psicologico in un campione di studenti delle scuole superiori.
Materiali e Metodi
Nel quadro del progetto DUSE, è stata condotta un’analisi preliminare su un campione di 57 adolescenti di età mediana 16 anni (range 15-17) di cui 35 M, 21 F, 1 NR. Sono stati somministrati i questionari validati DAB-Q e KIDSCREEN-27. Le analisi descrittive e di regressione sono state effettuate con il software R (livello di significatività statistica p ≤ 0.05).
Risultati
I risultati evidenziano che il sesso maschile è associato a pattern alimentari più salutari, livelli inferiori di sedentarietà e maggiore stabilità del benessere psicologico, mentre il sesso femminile presenta una maggiore variabilità in tali ambiti. Inoltre, si osserva una correlazione significativa tra scelte alimentari salutari e comportamento alimentare positivo (p = 0.034). Il comportamento sedentario si conferma un predittore significativo delle abitudini alimentari (β = 0.373, p = 0.004), suggerendo che livelli più bassi di sedentarietà sono associati a comportamenti alimentari più sani. Al contrario, il benessere psicologico non risulta significativamente associato alle abitudini alimentari (β = 0.098, p = 0.578). Il modello di regressione, pur risultando statisticamente significativo, presenta una limitata capacità esplicativa, mostrando un’elevata dispersione dei dati e un ampio intervallo di confidenza; ciò suggerisce la necessità di includere ulteriori variabili per comprendere appieno i determinanti delle scelte alimentari.
Conclusioni
I dati sottolineano l'importanza di adottare un approccio olistico negli interventi preventivi, che consideri la complessità e l'interazione tra i vari determinanti dello stile di vita e del benessere. Investire nella prevenzione e promuovere buone pratiche, sin dall'adolescenza, con particolare attenzione alle abitudini alimentari, è cruciale per migliorare la qualità della vita e ridurre i costi sanitari
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