1,293 research outputs found
IoT-based systems for soil nutrients assessment in horticulture
Soil nutrients assessment has great importance in horticulture. Implementation of an information system for horticulture faces many challenges: (i) great spatial variability within farms (e.g., hilly topography); (ii) different soil properties (e.g., different water holding capacity, different content in sand, sit, clay, and soil organic matter, different pH, and different permeability) for different cultivated plants; (iii) different soil nutrient uptake by different cultivated plants; (iv) small size of monoculture; and (v) great variety of farm components, agroecological zone, and socio-economic factors. Advances in information and communication technologies enable creation of low cost, efficient information systems that would improve resources management and increase productivity and sustainability of horticultural farms. We present an information system based on different sensing capability, Internet of Things, and mobile application for horticultural farms. An overview on different techniques and technologies for soil fertility evaluation is also presented. The results obtained in a botanical garden that simulates the diversity of environment and plant diversity of a horticultural farm are discussed considering the challenges identified in the literature and field research. The study provides a theoretical basis and technical support for the development of technologies that enable horticultural farmers to improve resources management.info:eu-repo/semantics/publishedVersio
Fear or humour in anti-smoking campaigns? Impact on perceived effectiveness and support for tobacco control policies
Several anti-smoking campaigns have been used for decades to reduce smoking consumption. However, so far, there is no consensus regarding the effectiveness of inducing distinct emotions in reducing smoke consumption. This study tested the effects of two types of anti-smoking ads, inducing fear or humor, on emotions, perceived effectiveness, support for tobacco control policies, urges to smoke, and susceptibility to smoke. Participants (N = 108; 54 smokers) of both genders were randomly assigned to one of the two following emotion ads condition: fear (N = 52) or humor (N = 56). During exposure, the continuous flow of their emotions by self-report and physiologically was collected. Measures of ads impact on emotions, perceived effectiveness, urges and susceptibility to smoking, and support for tobacco policies were applied after exposure. The results have shown that fear ads were perceived as more effective and reduced the urges to smoke in smokers. Non-smokers were more supportive of tobacco control policies. In conclusion, this study showed that fear campaigns can reduce the urge to smoke among smokers and are perceived to be more effective. This perceived effectiveness can be partially explained by feelings of fear, regardless the other emotions it also triggers, and of the smoking status.info:eu-repo/semantics/publishedVersio
Design and implementation of 3-D measurement method for container handling target
In the process of automatic container terminal loading and unloading, the threedimensional attitude of the container affects the security of loading and unloading operations, so the three-dimensional attitude positioning of the container is very important. In this paper, a visual non-contact measurement method is used to realize the real-time orientation of the threedimensional attitude of the container. First, the container corner is coarsely positioned by a smallscale deep learning network. Secondly, the precise position of the container keyhole is obtained by the secondary positioning of the container corner through the traditional image processing
algorithm, and the container posture is measured in three dimensions by combining the physical motion model of the container during loading and unloading. After testing, unlike previous
measurement methods, the measurement accuracy of this method met the requirements of automatic loading and unloading of container terminals, and the measurement time met the
requirements of real-time measurement.info:eu-repo/semantics/publishedVersio
Serious game for physical rehabilitation: measuring the effectiveness of virtual and real training environments
Recent advances in low-cost natural user interfaces such as Microsoft Kinect and Leap Motion controller allow the Virtual Reality implementation of 3D serious games for, posture, upper limb and lower limb rehabilitation purposes. However, it is very important to compare the results obtained by the users that train in virtual and real environments. This paper presents a virtual reality serious game for upper limb rehabilitation using a natural user interface expressed by Leap Motion controller. One of the developed virtual reality serious game for rehabilitation is converted to a real scenario with the same elements and rules and the same aims of physical rehabilitation. In order to extract appropriate information from the serious game based on real objects a RFID technology was used together with software components developed in LabVIEW. The evaluation of hand muscles' activity during the training session is based on the usage of thermography that permits to measure in an unobtrusive way the distribution of the temperature on the hands' level. Based on analysis of thermographic images obtained before and after serious game practice, the level of activity of specific muscles associated with training for virtual and real scenario is extracted. Experimental results that are also included in the paper underline the effectiveness of the proposed method for the comparison of the training in virtual and real scenarios.info:eu-repo/semantics/acceptedVersio
A Dual Measurement and Stimulating System to Monitor and Promote NNS
The present paper presents a dual system that can be used to measure and to generate
non-nutritive sucking (NNS) signals. The NNS measurement is based on a pressure sensor that
is pneumatically connected to a silicone pacifier. By its turn, the NNS stimulator is based on a
miniature pump and a miniature electro-valve that are operated by opposite phased signals to
produce the pulsed pressure signal that is pneumatically applied to the silicone pacifier. The
paper highlights some specific issues related with the calibration of the pneumatic signal
measuring chain. Processing and wireless transmission capabilities are provided by a low-cost
solution based on a microcontroller. Calibration and experimental results are also included in
the paper.info:eu-repo/semantics/publishedVersio
Software Based Sigma-Delta Converter with Auto-Calibration Capabilities
Trabalho apresentado em 1st IFSA Frequency & Time Conference (IFTC’ 2019), setembro 2019, Tenerife, EspanhaThis paper presents a software based sigma-delta converter. The proposed A/D converter represents a lowcost
and flexible digitalization solution that can be used in a large number of applications. The proposed discrete A/D
converter tasks, that are performed by a microcontroller, include: digital filtering, oversampling, noise shaping and
decimation. A simple implementation of the digital filtering is easily implemented by counting the number of high and low
pulses contained in the feedback bit stream generated by the microcontroller.
The first part of the paper contains an overview of the main characteristics of sigma-delta converters, the second part
includes a brief description of the proposed sigma-delta converter, hardware, software and implementation details, and the
last part will include simulation and experimental results.N/
Wearable biopotential measurement using the TI ADS1198 analog front-end and textile electrodes : signal conditioning and signal quality assessment
The development of mobile systems for monitoring bioelectric signals outside a hospital environment involves many challenges that do not arise when it is in a controlled environment, like a hospital. The dimensions of these systems are an important factor to consider in order to facilitate their use without interfering with the daily activities of individuals.
The purpose of this work is the implementation of a single-supply battery-powered, low power ECG/EMG signal monitoring system based on the ADS1198 Analog Front-End from Texas Instruments. The system was designed to acquire ECG signals from three electrodes using the integrated Right-Leg-Drive (RLD) circuit from the ADS1198.
The developed analog front-end was connected for testing purposes through the SPI interface to a NI-USB 8451 board and signals were acquired using LabVIEW. The circuit was tested in several situations and proved to provide high quality signals using textile integrated electrodes and conventional disposable gel electrodes.FEDER- “Programa Operacional Factores de Competitividade – COMPETE”, FCT - Fundação para a Ciência e a Tecnologia, projects PEst-C/CTM/UI0264/2011 and PTDC/EEA-ELC/70803/2006, and Instituto de Telecomunicaçõe
Continuous health monitoring using e-textile integrated biosensors
In this work, continuous health monitoring for
disabled or elderly people is proposed using textile integrated electrodes for ECG measurement. Other applications, such as EMG or skin impedance measurement are also envisaged. The paper specifically describes a shirt integrating electrodes for ECG measurement that has been tested in several conditions. The techniques for integration of ECG electrodes can be directly applied for production of EMG or skin-impedance electrodes.Signal processing techniques for heart rate value extraction and to deal with low-quality signal or motion artefacts are being tested and will also be described. Results show that signals
acquired with the shirt are comparable to signals acquired with conventional gel electrodes. The complete integration of the electrodes into clothing may have a very interesting psychological benefit, but some issues related to comfort and daily use have to be further investigated.Fundação para a Ciência e a Tecnologia (FCT
The Association between Childhood Obesity and Cardiovascular Changes in 10 Years Using Special Data Science Analysis
The increasing prevalence of overweight and obesity is a worldwide problem, with several well-known consequences that might start to develop early in life during childhood. The present research based on data from children that have been followed since birth in a previously established cohort study (Generation XXI, Porto, Portugal), taking advantage of State-of-the-Art (SoA) data science techniques and methods, including Neural Architecture Search (NAS), explainable Artificial Intelligence (XAI), and Deep Learning (DL), aimed to explore the hidden value of data, namely on electrocardiogram (ECG) records performed during follow-up visits. The combination of these techniques allowed us to clarify subtle cardiovascular changes already present at 10 years of age, which are evident from ECG analysis and probably induced by the presence of obesity. The proposed novel combination of new methodologies and techniques is discussed, as well as their applicability in other health domains.João Rala Cordeiro received support from Fundação para a Ciência e Tecnologia (PhD Research Scholarship reference 2020.07443.BD)
Effects of Vagal Stimulation on Induction and Termination of Atrial Fibrillation in an in Vivo Rabbit Heart Model
INTRODUCTION: Vagal activity is thought to influence atrial electrophysiological properties and play a role in the initiation and maintenance of atrial fibrillation (AF). In this study, we assessed the effects of acute vagal stimulation (vagus_stim) on atrial conduction times, atrial and pulmonary vein (PV) refractoriness, and vulnerability to induction of AF in the rabbit heart with intact autonomic innervation.
METHODS: An open-chest epicardial approach was performed in 11 rabbits (New Zealand; 3.9-5.0 kg), anesthetized and artificially ventilated after neuromuscular blockade. A 3-lead ECG was obtained. Atrial electrograms were recorded along the atria, from right to left (four monopolar electrodes), together with a circular electrode adapted for proximal left PV assessment. Acute vagus nerve stimulation was obtained with bipolar electrodes (20 Hz). Epicardial activation was recorded in sinus rhythm, and the conduction time from right (RA) to left atrium (LA), and from RA to PVs, was measured in basal conditions and during vagus_stim. The atrial effective refractory period (ERP) and dispersion of refractoriness (Disp_A) were analyzed. Vulnerability to AF induction was assessed at the right (RAA) and left (LAA) atrial appendages and the PVs. Atrial stimulation (50 Hz) was performed alone or combined with vagus_stim. Heart rate and blood pressure were monitored.
RESULTS: In basal conditions, there was a significant delay in conduction from RA to PVs, not influenced by vagus_stim, and the PV ERPs were shorter than those measured in LA and LAA, but without significant differences compared to RA and RAA. During vagus_stim, conduction times between RA and LA increased from 16+8 ms to 27+6 ms (p 10 s in 45.4% of rabbits during vagus_stim, and ceased after vagus_stim in 4 out of these 5 cases. In 3 animals, PV tachycardia, with fibrillatory conduction, induced with 50 Hz PV pacing during vagus_stim.
CONCLUSIONS: Vagus_stim reduces interatrial conduction velocity and significantly shortens atrial ERP, contributing to the induction and duration of AF episodes in the in vivo rabbit heart. This model may be useful for the assessment of autonomic influence on the pathophysiology of AF
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