862 resultados para Sensor-based Learning


Relevância:

80.00% 80.00%

Publicador:

Resumo:

The sensing of carbon dioxide (CO2) at room temperature, which has potential applications in environmental monitoring, healthcare, mining, biotechnology, food industry, etc., is a challenge for the scientific community due to the relative inertness of CO2. Here, we propose a novel gas sensor based on clad-etched Fiber Bragg Grating (FBG) with polyallylamine-amino-carbon nanotube coated on the surface of the core for detecting the concentrations of CO2 gas at room temperature, in ppm levels over a wide range (1000 ppm-4000 ppm). The limit of detection observed in polyallylamine-amino-carbon nanotube coated core-FBG has been found to be about 75 ppm. In this approach, when CO2 gas molecules interact with the polyallylamine-amino-carbon nanotube coated FBG, the effective refractive index of the fiber core changes, resulting in a shift in Bragg wavelength. The experimental data show a linear response of Bragg wavelength shift for increase in concentration of CO2 gas. Besides being reproducible and repeatable, the technique is fast, compact, and highly sensitive. (C) 2013 AIP Publishing LLC.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

Detection of petroleum leakages in pipelines and storage tanks is a very important as it may lead to significant pollution of the environment, accidental hazards, and also it is a very important fuel resource. Petroleum leakage detection sensor based on fiber optics was fabricated by etching the fiber Bragg grating (FBG) to a region where the total internal reflection is affected. The experiment shows that the reflected Bragg's wavelength and intensity goes to zero when etched FBG is in air and recovers Bragg's wavelength and intensity when it is comes in contact with petroleum or any external fluid. This acts as high sensitive, fast response fluid optical switch in liquid level sensing, petroleum leakage detection etc. In this paper we present our results on using this technique in petroleum leakage detection.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

Single-stranded DNA (ssDNA) is a prerequisite for electrochemical sensor-based detection of parasite DNA and other diagnostic applications. To achieve this detection, an asymmetric polymerase chain reaction method was optimised. This method facilitates amplification of ssDNA from the human lymphatic filarial parasite Wuchereria bancrofti. This procedure produced ssDNA fragments of 188 bp in a single step when primer pairs (forward and reverse) were used at a 100:1 molar ratio in the presence of double-stranded template DNA. The ssDNA thus produced was suitable for immobilisation as probe onto the surface of an Indium tin oxide electrode and hybridisation in a system for sequence-specific electrochemical detection of W. bancrofti. The hybridisation of the ssDNA probe and target ssDNA led to considerable decreases in both the anodic and the cathodic currents of the system's redox couple compared with the unhybridised DNA and could be detected via cyclic voltammetry. This method is reproducible and avoids many of the difficulties encountered by conventional methods of filarial parasite DNA detection; thus, it has potential in xenomonitoring.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

In this paper, we present a machine learning approach for subject independent human action recognition using depth camera, emphasizing the importance of depth in recognition of actions. The proposed approach uses the flow information of all 3 dimensions to classify an action. In our approach, we have obtained the 2-D optical flow and used it along with the depth image to obtain the depth flow (Z motion vectors). The obtained flow captures the dynamics of the actions in space time. Feature vectors are obtained by averaging the 3-D motion over a grid laid over the silhouette in a hierarchical fashion. These hierarchical fine to coarse windows capture the motion dynamics of the object at various scales. The extracted features are used to train a Meta-cognitive Radial Basis Function Network (McRBFN) that uses a Projection Based Learning (PBL) algorithm, referred to as PBL-McRBFN, henceforth. PBL-McRBFN begins with zero hidden neurons and builds the network based on the best human learning strategy, namely, self-regulated learning in a meta-cognitive environment. When a sample is used for learning, PBLMcRBFN uses the sample overlapping conditions, and a projection based learning algorithm to estimate the parameters of the network. The performance of PBL-McRBFN is compared to that of a Support Vector Machine (SVM) and Extreme Learning Machine (ELM) classifiers with representation of every person and action in the training and testing datasets. Performance study shows that PBL-McRBFN outperforms these classifiers in recognizing actions in 3-D. Further, a subject-independent study is conducted by leave-one-subject-out strategy and its generalization performance is tested. It is observed from the subject-independent study that McRBFN is capable of generalizing actions accurately. The performance of the proposed approach is benchmarked with Video Analytics Lab (VAL) dataset and Berkeley Multimodal Human Action Database (MHAD). (C) 2013 Elsevier Ltd. All rights reserved.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

This paper describes an ab initio design and development of a novel Fiber Bragg Grating (FBG) sensor based strain sensing plate for the measurement of plantar strain distribution in human foot. The primary aim of this work is to study the feasibility of usage of FBG sensors in the measurement of plantar strain in the foot; in particular, to spatially resolve the strain distribution in the foot at different regions such as fore-foot, mid-foot and hind-foot. This study also provides a method to quantify and compare relative postural stability of different subjects under test; in addition, traditional accelerometers have been used to record the movements of center of gravity (second lumbar vertebra) of the subject and the results obtained have been compared against the outcome of the postural stability studies undertaken using the developed FBG plantar strain sensing plate. (C) 2013 Elsevier Ltd. All rights reserved.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

Prognosis regarding durability of composite structures using various Structural Health Monitoring (SHM) techniques is an important and challenging topic of research. Ultrasonic SHM systems with embedded transducers have potential application here due to their instant monitoring capability, compact packaging potential toward unobtrusiveness and non-invasiveness as compared to non-contact ultrasonic and eddy current techniques which require disassembly of the structure. However, embedded sensors pose a risk to the structure by acting as a flaw thereby reducing life. The present paper focuses on the determination of strength and fatigue life of the composite laminate with embedded film sensors like CNT nanocomposite, PVDF thin films and piezoceramic films. First, the techniques of embedding these sensors in composite laminates is described followed by the determination of static strength and fatigue life at coupon level testing in Universal Testing Machine (UTM). Failure mechanisms of the composite laminate with embedded sensors are studied for static and dynamic loading cases. The coupons are monitored for loading and failure using the embedded sensors. A comparison of the performance of these three types of embedded sensors is made to study their suitability in various applications. These three types of embedded sensors cover a wide variety of applications, and prove to be viable in embedded sensor based SHM of composite structures.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

In this letter, we present the results of systematic experimental investigations of the effect of different chemical environments on the low frequency resistance fluctuations of single layer graphene field effect transistors. The shape of the power spectral density of noise was found to be determined by the energetics of the adsorption-desorption of molecules from the graphene surface making it the dominant source of noise in these devices. We also demonstrate a method of quantitatively determining the adsorption energies of chemicals on graphene surface based on noise measurements. We find that the magnitude of noise is extremely sensitive to the nature and amount of the chemical species present. We propose that a chemical sensor based on the measurement of low frequency resistance fluctuations of single layer graphene field effect transistor devices will have extremely high sensitivity, very high specificity, high fidelity, and fast response times. (c) 2015 AIP Publishing LLC.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

Abstract-This paper reports a single-crystal silicon mass sensor based on a square-plate resonant structure excited in the wine glass bulk acoustic mode at a resonant frequency of 2.065 MHz and an impressive quality factor of 4 million at 12 mtorr pressure. Mass loading on the resonator results in a linear downshift in the resonant frequency of this device, wherein the measured sensitivity is found to be 175 Hz cm2/μg. The silicon resonator is embedded in an oscillator feedback loop, which has a short-term frequency stability of 3 mHz (approximately 1.5 ppb) at an operating pressure of 3.2 mtorr, corresponding to an equivalent mass noise floor of 17 pg/cm2. Possible applications of this device include thin film monitoring and gas sensing, with the potential added benefits of scalability and integration with CMOS technology. © 2008 IEEE.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

Este informe recoge las guías del docente y del estudiante para la puesta en marcha, seguimiento continuo y evaluación de la asignatura Ingeniería del Software del segundo curso del Grado en Ingeniería Informática. Todo ello basado en metodologías activas, concretamente la metodología de Aprendizaje Basado en Proyectos (ABP, o PBL de Project Based Learning). El trabajo publicado en este informe es el resultado obtenido por los autores dentro del programa de formación del profesorado en metodologías activas (ERAGIN), auspiciado por el Vicerrectorado de Calidad e Innovación Docente de la Universidad del País Vasco (UPV/EHU).

Relevância:

80.00% 80.00%

Publicador:

Resumo:

Se presentan herramientas y material de apoyo para aplicar la metodología de aprendizaje cooperativo en la docencia universitaria, con una orientación especial a ingeniería.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

Networks for Knowledge (n4k Ltd) are a Work Based Learning organisation which specialises in Early Years Education. Training and Development Manager, Elaine Wareing has developed the use of Facebook and Twitter to promote peer learning and interaction beyond the classroom. It also allows trainers to discuss ideas and challengers with a wider group of learners. This has allowed practitioners across a wide geographical area to share their thoughts and ideas together on some of the subjects relating to early years practice.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

Headjogs is a well established hair academy within the Essex and East of London region. This work-based learning provider is run by Stephen Daly, Director, and Debbie Scott. Around six months ago, Debbie participated in the e-Guides programme, where she gained the expertise to implement innovative technology into the curriculum. Since then they have received Association of Learning Providers (ALP) Learner Innovation Grant funding with which they plan to reinforce their innovative approach to hairdressing.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

Work-based learning provider, KEITS has improved efficiencies and institutional effectiveness with the introduction of Blackberry mobile devices to all their assessors. They have saved time and money on paper and travel, diversified evidence capture and improved their overall engagement with learners.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

Crossing the Threshold, one of a series of advice and guidance publications, is designed to support use of the online e-Portfolio Implementation Toolkit and video case studies by those involved in wide-scale implementation of e-portfolios in their institutions. As the resources address the needs of both managers and practitioners, the publication has relevance for a wide range of readers in further and higher education and work-based learning. To assist the planning and effective management of a large-scale e-portfolio implementation, Crossing the Threshold follows the stages of an implementation journey with insights and guidance drawn from the toolkit and its supporting case studies. Links are provided throughout the publication to more detailed information in the two online resources.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

Effective Practice in a Digital Age is designed for those in further and higher education who aim to enhance the student learning experience through apt and imaginative uses of technology. A visually rich publication, Effective Practice in a Digital Age outlines key aspects of designing learning in a technology-rich context and is structured to address the needs of experienced practitioners as well as those new to technology-based learning and teaching – the ten newly researched case studies offer a choice of pathways reflecting the diversity of approaches taken by practitioners in current UK practice.