1,721,077 research outputs found
Metodo per il controllo di un sistema meccanico articolato e⁄o deformabile e sue applicazioni
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METHOD FOR CONTROLLING AN ARTICULATED AND/OR DEFORMABLE MECHANICAL SYSTEM AND ITS APPLICATIONS
No full textTowards a Real-Time Transduction and Classification of Chemo-Resistive Sensor Array Signals
No full textRecently, a growing interest in artificial implementations of biological systems has been arising. In particular, several research groups have been working in mimicking the mammalian olfactory system with the so-called electronic noses (e-noses). The e-noses, which are based on a sensor array, a fluid-dynamic system, and a data processing unit, are systems devoted to detecting and analyzing volatiles, where a deep knowledge of the target application is needed. In order to achieve effective results the sampling system, the measurement protocols, the sensor array, and the pattern recognition techniques have to be carefully designed. The increasing complexity of such design poses issues in sensory feature extraction and fusion, drift compensation, and data processing, especially when high efficiency is required for real-time applications. The interconnection and cooperation of several modules devoted to processing different tasks, such as control, data acquisition, data filtering interfaces, feature selection, and pattern analysis, are already mandatory. Moreover, heterogeneous techniques used to implement such tasks may introduce module interconnection and cooperation issues.
In this paper, we address the development of a dedicated instrument able to perform real-time transduction, fusion, and processing of chemoresistive sensor array signals. In particular, this instrument realizes a dynamic and efficient management of data processing techniques and automatically controls the measurement protocols and the sampling system. An array of conducting poly (alkoxy-bithiophenes) sensors, the fluid-dynamic system, the electronic section, the framework's base architecture, and the implementation of dedicated application processes are described. The classification task is based on a self-organizing map where models for artificial neurons and connections were derived from the base structures available in the framework core. According to the target application, this instrument is portable and easily tailored, calibrated, and trained. Classification of olive oil headspaces supports its utility in supplying high-efficiency routine for volatile organic compounds detection and analysis
“A radially symmetric measurement chamber for electronic noses”
No full textA measurement chamber for the dynamic exposure of a sensor array to gaseous or liquid samples is presented. The device has been designed to optimise sensor response signals in terms of stability, reproducibility, response time and amplitude. This chamber has a radially symmetric flow splitter, which allows homogeneous flow conditions with low velocity gradients, and avoids significant recirculating zones and stagnant volumes. These characteristics, together with the fact that sample paths from the inlet to the sensors and from the sensors to the outlet have the same length, guarantee that all sensors are always exposed to the same chemical sample under the same experimental conditions. Through mathematical models, the introduction of a tracer in the form of a square wave concentration signal was simulated, and the effects of the working tolerances of the device main component on flow conditions were discusse
Backpropagation-Based Non Linear PCA for Biomedical Applications
No full textMachine learning methodologies such as artificial neural networks (ANN), fuzzy logic or genetic programming, as well as principal component analysis (PCA) and intelligent control have been recently introduced in medicine. ANNs imitate the structure and workings of the human brain by means of mathematical models able to adapt several parameters. ANNs learn the input/output behavior of a system through a supervised or an unsupervised learning algorithm. In this work, we present and demonstrate a new pre-processing algorithm able to improve the performance of an ANN in the processing of biomedical datasets. The algorithm was tested analyzing lung function and fractional exhaled nitric oxide differences in the breath in children with allergic bronchial asthma and in normal population. Classification obtained using non linear PCA based on the new algorithm shows a better precision in separating asthmatic and control subjects
A new low-error approximation of artificial neurons sigmoid function and its derivative
No full textA new low-error approximation of the sigmoid function based on the piecewise linear method is proposed. The approximation results, in comparison with those of the state-of-the-art, show the lowest mean absolute and relative errors
The promise of the metaverse in mental health: the new era of MEDverse
No full textSince Mark Zuckerberg’s announcement about the development of new three-dimensional virtual worlds for social communication, a great debate has been raised about the promise of such a technology. The metaverse, a term formed by combining meta and universe, could open a new era in mental health, mainly in psychological disorders, where the creation of a full-body illusion via digital avatar could promote healthcare and personal well-being. Patients affected by body dysmorphism symptoms (i.e., eating disorders), social deficits (i.e. autism) could greatly benefit from this kind of technology. However, it is not clear which advantage the metaverse would have in treating psychological disorders with respect to the well-known and effective virtual reality (VR) exposure therapy. Indeed, in the last twenty years, a plethora of studies have demonstrated the effectiveness of VR technology in reducing symptoms of pain, anxiety, stress, as well as, in improving cognitive and social skills. We hypothesize that the metaverse will offer more opportunities, such as a more complex, virtual realm where sensory inputs, and recurrent feedback, mediated by a “federation” of multiple technologies - e.g., artificial intelligence, tangible interfaces, Internet of Things and blockchain, can be reinterpreted for facilitating a new kind of communication overcoming self-body representation. However, nowadays a clear starting point does not exist. For this reason, it is worth defining a theoretical framework for applying this new kind of technology in a social neuroscience context for developing accurate solutions to mental health in the future
AUTISM AND LACK OF D3 VITAMIN: A SYSTEMATIC REVIEW
No full textutism Spectrum Disorder (ASD) is a complex neurodevelopmental disorder characterized by social communication deficits and restricted, repetitive patterns of behavior. Several medical conditions including gastrointestinal (GI) problems, asthma and allergies have been associated with ASD, and multiple risk factors, both genetic and environmental, have been proposed. Among them, vitamin D (VD) deficiency is probably associated with ASD, and may play a role in the condition.
We conducted a systematic review of the literature for the period January 1, 2010 through June 15, 2014, according to PRISMA guidelines, aiming to investigate the complex biological interplay between VD, metabolism, immune system and nervous system in ASD.
Different trends in the association between ASD and VD deficiency have been observed, and factors such as gender, ethnicity, sampling, and methodology play a role in the results and outcomes.
At present, for at least a subgroup of ASD individuals, an imbalance in VD metabolism probably exists and may be associated with the condition. In this cohort, VD replacement in these individuals might contribute to improving ASD symptoms and/or associated conditions. This topic is an important challenge for future research, and could lead to a new tailored therapeutic approach for VD in ASD
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