Open AccessArticle
Quantification of Feto-Maternal Heart Rate from Abdominal ECG Signal Using Empirical Mode Decomposition for Heart Rate Variability Analysis
Technologies 2017, 5(4), 68; doi:10.3390/technologies5040068 (registering DOI) -
Abstract
In this paper, a robust method of feto-maternal heart rate extraction from the non-invasive composite abdominal Electrocardiogram (aECG) signal is presented. The proposed method is based on the Complete Ensemble Empirical Mode Decomposition with Adaptive Noise (CEEMDAN) method, in which a composite aECG
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In this paper, a robust method of feto-maternal heart rate extraction from the non-invasive composite abdominal Electrocardiogram (aECG) signal is presented. The proposed method is based on the Complete Ensemble Empirical Mode Decomposition with Adaptive Noise (CEEMDAN) method, in which a composite aECG signal is decomposed into its constituent frequency components called Intrinsic Mode Functions (IMFs) or simply “modes”, with better spectral separation. Decomposed IMFs are then selected manually according to probable maternal and fetal heart rate information and are processed further for quantification of maternal and fetal heart rate and variability analysis. The proposed method was applied to aECG recordings collected from three different sources: (i) the PhysioNet (adfecgdb) database; (ii) the PhysioNet (nifecgdb) database; and (iii) synthetic aECG signal generated from mathematical modeling in the LabVIEW software environment. An overall sensitivity of 98.83%, positive diagnostic value of 97.97%, accuracy of 96.93% and performance index of 96.75% were obtained in the case of Maternal Heart Rate (MHR) quantification, and an overall sensitivity of 98.13%, positive diagnostic value of 97.62%, accuracy of 95.91% and performance index of 95.69% were obtained in case of Fetal Heart Rate (FHR) quantification. The obtained results confirm that CEEMDAN is a very robust and accurate method for extraction of feto-maternal heart rate components from aECG signals. We also conclude that non-invasive aECG is an effective and reliable method for long-term FHR and MHR monitoring during pregnancy and labor. The requirement of manual intervention while selecting the probable maternal and fetal components from “n” number of decomposed modes limits the real-time application of the proposed methodology. This is due to the fact that the number of modes “n” produced by the CEEMDAN decomposition is unpredictable. However, the proposed methodology is well suited for applications where a small time-delay or offset in feto-maternal monitoring can be acceptable. In future, application-specific modification of the CEEMDAN algorithm can be implemented to eliminate manual intervention completely and will be suitable for long-term feto-maternal monitoring. Full article
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Open AccessArticle
Correlation of Infrared Thermal Imaging Results with Visual Inspection and Current-Voltage Data of PV Modules Installed in Kumasi, a Hot, Humid Region of Sub-Saharan Africa
Technologies 2017, 5(4), 67; doi:10.3390/technologies5040067 -
Abstract
In this study, a photovoltaic (PV) modules site installed from 1997 to 2017 (20 years of outdoor exposure) in the hot, humid region of Kumasi, Ghana in Sub-Saharan Africa was selected in order to study the aging phenomenon and rate of degradation due
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In this study, a photovoltaic (PV) modules site installed from 1997 to 2017 (20 years of outdoor exposure) in the hot, humid region of Kumasi, Ghana in Sub-Saharan Africa was selected in order to study the aging phenomenon and rate of degradation due to long-term exposure. The main purpose of this work was to correlate the performance of 14 PV modules using data from infra-red thermal imaging (hot spot tests), current-voltage (I-V) tests and visual inspection. The modules were first visually inspected followed by electrical performance tests using an I-V curve tracer. Hot spot testing of each module was performed to enable further characterization. The results of the visual inspection using the United States National Renewable Energy Laboratory (NREL) checklist did not show any major observable defects. The results also show that the higher the temperature difference in the hot spot tests, the higher the rate of power degradation. Eleven modules failed the hot spot tests according to the criteria indicated in the literature. The average power degradation rate was 1.36%/year, which is above the industry-accepted range of 0.7–1.0%/year. The results provide evidence of a positive correlation between temperature difference and performance parameters such as power degradation (Pdeg), power performance factor (PPF) and power drop (Pdrop). The power performance factor for all 14 modules fell below the average 80% standard set by most manufacturers for modules operating within the 25-year warranty. Full article
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Open AccessFeature PaperArticle
An Approach for the Simulation of Ground and Honed Technical Surfaces for Training Classifiers
Technologies 2017, 5(4), 66; doi:10.3390/technologies5040066 -
Abstract
Training of neural networks requires large amounts of data. Simulated data sets can be helpful if the data required for the training is not available. However, the applicability of simulated data sets for training neuronal networks depends on the quality of the simulation
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Training of neural networks requires large amounts of data. Simulated data sets can be helpful if the data required for the training is not available. However, the applicability of simulated data sets for training neuronal networks depends on the quality of the simulation model used. A simple and fast approach for the simulation of ground and honed surfaces with predefined properties is being presented. The approach is used to generate a diverse data set. This set is then applied to train a neural convolution network for surface type recognition. The resulting classifier is validated on the basis of a series of real measurement data and a classification rate of >85% is achieved. A possible field of application of the presented procedure is the support of measurement technicians in the standard-compliant evaluation of measurement data by suggestion of specific data processing steps, depending on the recognized type of manufacturing process. Full article
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Open AccessArticle
Bushfire Disaster Monitoring System Using Low Power Wide Area Networks (LPWAN)
Technologies 2017, 5(4), 65; doi:10.3390/technologies5040065 -
Abstract
Some applications, including disaster monitoring and recovery networks, use low-power wide-area networks (LPWAN). LPWAN sensors capture data bits and transmit them to public carrier networks (e.g., cellular networks) via dedicated gateways. One of the challenges encountered in disaster management scenarios revolves around the
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Some applications, including disaster monitoring and recovery networks, use low-power wide-area networks (LPWAN). LPWAN sensors capture data bits and transmit them to public carrier networks (e.g., cellular networks) via dedicated gateways. One of the challenges encountered in disaster management scenarios revolves around the carry/forward sensed data and geographical location information dissemination to the disaster relief operatives (disaster relief agency; DRA) to identify, characterise, and prioritise the affected areas. There are network topology options to reach its destination, including cellular, circuit switched, and peer-to-peer networks. In the context of natural disaster prediction, it is vital to access geographical location data as well as the timestamp. This paper proposes the usage of Pseudo A Number (PAN), that is, the calling party address, which is used by every network to include the location information instead of the actual calling party address of the gateway in LPWAN. This PAN information can be further analysed by the DRA to identify the affected areas and predict the complications of the disaster impacts in addition to the past history of damages. This paper aims to propose a solution that can predict disaster proceedings based on propagation and the velocity of impact using vector calculation of the location data and the timestamp, which are transmitted by sensors through the PAN of the gateway in LPWAN. Full article
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Open AccessArticle
Combining Electromyography and Tactile Myography to Improve Hand and Wrist Activity Detection in Prostheses
Technologies 2017, 5(4), 64; doi:10.3390/technologies5040064 -
Abstract
Despite recent advances in prosthetics and assistive robotics in general, robust simultaneous and proportional control of dexterous prosthetic devices remains an unsolved problem, mainly because of inadequate sensorization. In this paper, we study the application of regression to muscle activity, detected using a
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Despite recent advances in prosthetics and assistive robotics in general, robust simultaneous and proportional control of dexterous prosthetic devices remains an unsolved problem, mainly because of inadequate sensorization. In this paper, we study the application of regression to muscle activity, detected using a flexible tactile sensor recording muscle bulging in the forearm (tactile myography—TMG). The sensor is made of 320 highly sensitive cells organized in an array forming a bracelet. We propose the use of Gaussian process regression to improve the prediction of wrist, hand and single-finger activation, using TMG, surface electromyography (sEMG; the traditional approach in the field), and a combination of the two. We prove the effectiveness of the approach for different levels of activations in a real-time goal-reaching experiment using tactile data. Furthermore, we performed a batch comparison between the different forms of sensorization, using a Gaussian process with different kernel distances. Full article
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Open AccessArticle
The Non-Euclidean Hydrodynamic Klein–Gordon Equation with Perturbative Self-Interacting Field
Technologies 2017, 5(4), 63; doi:10.3390/technologies5040063 -
Abstract
In this paper the quantum hydrodynamic approach for the Klein–Gordon equation (KGE) owning a perturbative self-interaction term is developed. The generalized model to non-Euclidean space–time allows for the determination of the quantum energy impulse tensor density of mesons, for the gravitational equation of
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In this paper the quantum hydrodynamic approach for the Klein–Gordon equation (KGE) owning a perturbative self-interaction term is developed. The generalized model to non-Euclidean space–time allows for the determination of the quantum energy impulse tensor density of mesons, for the gravitational equation of quantum mechanical systems. Full article
Open AccessArticle
Estimating Potential Methane Emission from Municipal Solid Waste and a Site Suitability Analysis of Existing Landfills in Delhi, India
Technologies 2017, 5(4), 62; doi:10.3390/technologies5040062 -
Abstract
The management of rapidly growing municipal solid waste (MSW) is one of the major challenges in developing countries. The current study also estimates the suitability of a site through a geographical information system using multi-criteria decision analysis (MCDA) for landfill sites in National
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The management of rapidly growing municipal solid waste (MSW) is one of the major challenges in developing countries. The current study also estimates the suitability of a site through a geographical information system using multi-criteria decision analysis (MCDA) for landfill sites in National Capital Territory (NCT). The results of the suitability index indicate that only 58.7 km2 of the land is suitable for the construction of landfill sites, while 194.27 km2 of the total area is moderately suitable. The existing three landfill sites that are currently functional and used by government organizations as landfills are found to be moderately suitable. A large fraction of MSW is disposed in landfills, which emit one third of the total anthropogenic methane (CH4) and are considered an important contributor of Green House Gases (GHGs) to the atmosphere. Thus, there is a need for the proper estimation of GHG emission from landfills, specifically CH4, which contributes 20% of the GHGs that contribute to global warming. The current study aims to estimate the CH4 emission from landfills in the NCT, Delhi, India using GHG inventory guidelines from the Intergovernmental Panel on Climate Change (IPCC). The CH4 emission from landfills has doubled from 31.06 Gg/yr to 65.16 Gg/yr from 1999 and 2000 to 2015. The generation of CH4 from MSW is strongly correlated (R2 = 0.58) with the Gross State Domestic Product (GSDP), which is an indicator of wellbeing. Full article
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Open AccessArticle
Assessing Operator Wellbeing through Physiological Measurements in Real-Time—Towards Industrial Application
Technologies 2017, 5(4), 61; doi:10.3390/technologies5040061 -
Abstract
This article focuses on how operator wellbeing can be assessed to ensure social sustainability and operator performance at assembly stations. Rapid technological advances provide possibilities for assessing wellbeing in real-time, and from an assembly system perspective, this could enable the assessment of physiological
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This article focuses on how operator wellbeing can be assessed to ensure social sustainability and operator performance at assembly stations. Rapid technological advances provide possibilities for assessing wellbeing in real-time, and from an assembly system perspective, this could enable the assessment of physiological data in real-time. While technology is available, it has not been implemented or tested in industry. The aim of this paper was to investigate empirically how concurrent physiological measurement technologies can be integrated into an industrial application, in order to increase operator wellbeing and operator performance. A mixed method approach was used, which included a literature study, two laboratory tests, two case studies and a workshop. The results indicated that operator wellbeing could be assessed through electro-dermal activity, but that the data is perceived as difficult to interpret. For an industrial application, operator perception and data presentation are important and risks connected to personal integrity and IT-support need to be addressed. Future work includes testing how a combination of physiological measures and self-assessments can be used to assess operator wellbeing in an industrial context. Full article
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Open AccessArticle
Elderly in the Digital Era. Theoretical Perspectives on Assistive Technologies
Technologies 2017, 5(3), 60; doi:10.3390/technologies5030060 -
Abstract
The present paper presents a theoretical perspective on assistive technology for elderly people. In a context characterized by an aging population and an increased life expectancy, it is highly likely that we will become the spectators of a powerful pressure on the medical
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The present paper presents a theoretical perspective on assistive technology for elderly people. In a context characterized by an aging population and an increased life expectancy, it is highly likely that we will become the spectators of a powerful pressure on the medical assistance process. An increasing life expectancy means an increasing need of assistance for longer periods of time, which might become an unfeasible and unrealistic policy due to limited medical resources. In this context, assistive technology might become the only solution. Starting from an international context, this paper aims to theoretically present the way technology can be used as a tool for the elderly’s needs. Full article
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Open AccessArticle
Effect of AQM-Based RLC Buffer Management on the eNB Scheduling Algorithm in LTE Network
Technologies 2017, 5(3), 59; doi:10.3390/technologies5030059 -
Abstract
With the advancement of the Long-Term Evolution (LTE) network and smart-phones, most of today’s internet content is delivered via cellular links. Due to the nature of wireless signal propagation, the capacity of the last hop link can vary within a short period of
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With the advancement of the Long-Term Evolution (LTE) network and smart-phones, most of today’s internet content is delivered via cellular links. Due to the nature of wireless signal propagation, the capacity of the last hop link can vary within a short period of time. Unfortunately, Transmission Control Protocol (TCP) does not perform well in such scenarios, potentially leading to poor Quality of Service (QoS) (e.g., end-to-end throughput and delay) for the end user. In this work, we have studied the effect of Active Queue Management (AQM) based congestion control and intra LTE handover on the performance of different Medium Access Control (MAC) schedulers with TCP traffic by ns3 simulation. A proper AQM design in the Radio Link Control (RLC) buffer of eNB in the LTE network leads to the avoidance of forced drops and link under-utilization along with robustness to a variety of network traffic-loads. We first demonstrate that the original Random Early Detection (RED) linear dropping function cannot cope well with different traffic-load scenarios. Then, we establish a heuristic approach in which different non-linear functions are proposed with one parameter free to define. In our simulations, we demonstrate that the performance of different schedulers can be enhanced via proper dropping function. Full article
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Open AccessEditorial
Special Issue on “Additive Manufacturing Technologies and Applications”
Technologies 2017, 5(3), 58; doi:10.3390/technologies5030058 -
Abstract
Additive Manufacturing (AM) is a well-known technology, first patented in 1984 by the French scientist Alain Le Mehaute [...]
Full article
Open AccessTechnical Note
Semiclassical Length Measure from a Quantum-Gravity Wave Function
Technologies 2017, 5(3), 56; doi:10.3390/technologies5030056 -
Abstract
The definition of a length operator in quantum cosmology is usually influenced by a quantum theory for gravity considered. The semiclassical limit at the Planck age must meet the requirements implied in present observations. The features of a semiclassical wave-functional state are investigated,
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The definition of a length operator in quantum cosmology is usually influenced by a quantum theory for gravity considered. The semiclassical limit at the Planck age must meet the requirements implied in present observations. The features of a semiclassical wave-functional state are investigated, for which the modern measure(ment)s is consistent. The results of a length measurement at present times are compared with the same measurement operation at cosmological times. By this measure, it is possible to discriminate, within the same Planck-length expansion, the corrections to a Minkowski flat space possibly due to classicalization of quantum phenomena at the Planck time and those due to possible quantum-gravitational manifestations of present times. This analysis and the comparison with the previous literature can be framed as a test for the verification of the time at which anomalies at present related to the gravitational field, and, in particular, whether they are ascribed to the classicalization epoch. Indeed, it allows to discriminate not only within the possible quantum features of the quasi (Minkowski) flat spacetime, but also from (possibly Lorentz violating) phenomena detectable at high-energy astrophysical scales. The results of two different (coordinate) length measures have been compared both at cosmological time and as a perturbation element on flat Minkowski spacetime. The differences for the components of the corresponding classical(ized) metric tensor have been analyzed at different orders of expansions. The results of the expectation values of a length operator in the universe at the Planck time must be comparable with the same length measurements at present times, as far as the metric tensor is concerned. The comparison of the results of (straight) length measures in two different directions, in particular, can encode the pertinent information about the parameters defining the semiclassical wavefunctional for (semiclassicalized) gravitational field. Full article
Open AccessArticle
Characterising the Physical, Phytochemical and Antioxidant Properties of the Tuckeroo (Cupaniopsis anacardioides) Fruit
Technologies 2017, 5(3), 57; doi:10.3390/technologies5030057 -
Abstract
The tuckeroo (Cupaniopsis anacardioides) is an Australian native plant that fruits over the summer months. There are very few studies that have characterised its fruit; consequently, this study aimed to delineate the physical, phytochemical and antioxidant properties of the tuckeroo fruit.
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The tuckeroo (Cupaniopsis anacardioides) is an Australian native plant that fruits over the summer months. There are very few studies that have characterised its fruit; consequently, this study aimed to delineate the physical, phytochemical and antioxidant properties of the tuckeroo fruit. The tuckeroo skin embodied the largest weight proportion with over 77% of the total fruit weight and it had the highest levels of total phenolic compounds (TPC; 151.36 mg GAE/g), total flavonoids compounds (TFC; 95.94 mg CAE/g), and proanthocyanidins (Proanth; 164.86 mg CAE/g) content, as well as the strongest antioxidant power. The seed and flesh accounted for 23% of the total fruit weight and they possessed significantly lower levels of TPC, TFC and Proanth. This study has demonstrated that the tuckeroo fruit skin is a rich source of phenolic compounds, which can be further isolated and identified for further utilisation in the food and pharmaceutical industries. Full article
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Open AccessArticle
Sample Entropy Identifies Differences in Spontaneous Leg Movement Behavior between Infants with Typical Development and Infants at Risk of Developmental Delay
Technologies 2017, 5(3), 55; doi:10.3390/technologies5030055 -
Abstract
We are interested in using wearable sensor data to analyze detailed characteristics of movement, such as repeatability and variability of movement patterns, over days and months to accurately capture real-world infant behavior. The purpose of this study was to explore Sample Entropy (SampEn)
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We are interested in using wearable sensor data to analyze detailed characteristics of movement, such as repeatability and variability of movement patterns, over days and months to accurately capture real-world infant behavior. The purpose of this study was to explore Sample Entropy (SampEn) from wearable sensor data as a measure of variability of spontaneous infant leg movement and as a potential marker of the development of neuromotor control. We hypothesized that infants at risk (AR) of developmental delay would present significantly lower SampEn values than infants with typical development (TD). Participants were 11 infants with TD and 20 infants AR. We calculated SampEn from 1–4 periods of data of 7200 samples in length when the infants were actively playing across the day. The infants AR demonstrated smaller SampEn values (median 0.21) than the infants with TD (median 1.20). Lower values of SampEn indicate more similarity in patterns across time, and may indicate more repetitive, less exploratory behavior in infants AR compared to infants with TD. In future studies, we would like to expand to analyze longer periods of wearable sensor data and/or determine how to optimally sample representative periods across days and months. Full article
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Open AccessArticle
A Conceptual Framework for Implementing a WSN Based Cattle Recovery System in Case of Cattle Rustling in Kenya
Technologies 2017, 5(3), 54; doi:10.3390/technologies5030054 -
Abstract
This study proposes a framework for remote identification and tracking of cattle movement based on wireless sensor networks (WSN), mobile communication, and unmanned aerial vehicles (UAVs). The proposed framework can be implemented for tracking cattle movement at the village level and extended to
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This study proposes a framework for remote identification and tracking of cattle movement based on wireless sensor networks (WSN), mobile communication, and unmanned aerial vehicles (UAVs). The proposed framework can be implemented for tracking cattle movement at the village level and extended to harsh terrain when recovering stolen animals in case of cattle rustling or theft. The system works by identifying and tracking the desired animal location and sending periodic location data at regular intervals to a database as well as availing the specific animal’s current location on demand through the Internet and text messages. The proposed cattle tracking and recovery system (CTRS) consists of a rumen sensor module, a WSN control unit, a Worldwide Interoperability for Microwave Access (WiMAX) gateway, WiMAX base stations, and a data center. Availing timely information about the location of the stolen animals could facilitate quick recovery of the animals while ensuring the safety of the security personnel involved in the recovery process. Speedy recovery of stolen animals also defeats the purpose of cattle rustling as the rustlers do not have the chance to use the animals for their intended purposes. The proposed system was tested through a MATLAB simulation experiment. Full article
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Open AccessReview
Organic Solar Cell by Inkjet Printing—An Overview
Technologies 2017, 5(3), 53; doi:10.3390/technologies5030053 -
Abstract
In recent years, organic solar cells became more attractive due to their flexible power devices and the potential for low-cost manufacturing. Inkjet printing is a very potential manufacturing technique of organic solar cells because of its low material usage, flexibility, and large area
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In recent years, organic solar cells became more attractive due to their flexible power devices and the potential for low-cost manufacturing. Inkjet printing is a very potential manufacturing technique of organic solar cells because of its low material usage, flexibility, and large area formation. In this paper, we presented an overall review on the inkjet printing technology as well as advantages of inkjet-printing, comparison of inkjet printing with other printing technologies and its potential for organic solar cells (OSCs). Here we highlighted in more details about the viability of environment-friendly and cost-effective, non-halogenated indium tin oxide (ITO) free large scale roll to roll production of the OSC by inkjet printing technology. The challenges of inkjet printing like the viscosity limitations, nozzle clogging, coffee ring effect, and limitation of printability as well as dot spacing are also discussed. Lastly, some of the improvement strategies for getting the higher efficiency of the OSCs have been suggested. Full article
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Open AccessArticle
Teaching Enzyme Activity to the Visual Impaired and Blind Students
Technologies 2017, 5(3), 52; doi:10.3390/technologies5030052 -
Abstract
Biochemistry requires a high abstraction level, and different approaches should be used to enable the proper understanding of different subjects. In particular, students with visual impairment or blindness need special attention, not due to a lack of cognitive skills, but due to the
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Biochemistry requires a high abstraction level, and different approaches should be used to enable the proper understanding of different subjects. In particular, students with visual impairment or blindness need special attention, not due to a lack of cognitive skills, but due to the fact that most of the teaching methods are visual. Enzyme properties are usually taught through experimental data that show how the activity changes in different conditions, which end up with the analysis of graphs. Therefore, our group developed experiments and graphical representations that enable visually impaired and blind students to understand enzyme properties. The experiments were done with pineapple bromelain, using reconstituted dry milk and gelatin as substrates. The “visualization” of the results were based on the sensation of the viscosity of the samples. The graphs were made with cold porcelain with all the labels (legends and numbers) written in Braille with a positive slate. From our experience with a blind student, both the experiments and the graphic representations were useful adaptations for teaching enzyme properties. Full article
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Open AccessArticle
A Conceptual Test for Cognitively Coherent Quantum Gravity Models
Technologies 2017, 5(3), 51; doi:10.3390/technologies5030051 -
Abstract
In quantum gravity interpretations, the role of space- and time-related concepts is debated. Some argue that these concepts are not needed to describe physical reality at the Planck scale. Others object that an operational definition of magnitudes cannot get rid of spatiotemporal notions.
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In quantum gravity interpretations, the role of space- and time-related concepts is debated. Some argue that these concepts are not needed to describe physical reality at the Planck scale. Others object that an operational definition of magnitudes cannot get rid of spatiotemporal notions. We propose a “conceptual test” to assess if the mathematical content of a quantum gravity theory refers to some possibly verifiable empirical model. Given that any physical model describes the evolution of a set of measurables, these must be detectable in any empirical interpretation of a physical theory, including quantum gravity ones. Our test ultimately relies on considerations and studies concerning human cognitive limits in the discrimination of magnitudes. Full article
Open AccessArticle
Paste Extruder—Hardware Add-On for Desktop 3D Printers
Technologies 2017, 5(3), 50; doi:10.3390/technologies5030050 -
Abstract
This paper presents the design, development and testing of a paste/clay extrusion device intended to be used as a drop-in replacement for the conventional thermoplastic extruder of a desktop filament-based 3D printer. A plastic cylinder loaded with gel, paste or clay material is
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This paper presents the design, development and testing of a paste/clay extrusion device intended to be used as a drop-in replacement for the conventional thermoplastic extruder of a desktop filament-based 3D printer. A plastic cylinder loaded with gel, paste or clay material is placed into the device. Feedstock is pressed through an extrusion nozzle by a piston driven by an electrically actuated drive-screw and nut mechanism. The device allows the build material to heat up to 80 °C. Forced air cooling is used to assist the cooling or hardening process of the freshly-printed material during fabrication. The feedstock container, nozzle, and material-loading process are all suitable for use in a sterile environment. The device is designed for seamless integration with existing 3D printing firmware and slicing software. After designing the device, a prototype was produced and installed on a 3D printer. Silicone and acrylic polymers, as well as dental gel, were used to fabricate 3D printed sample objects. Full article
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Open AccessArticle
A Low-Cost, Wearable Opto-Inertial 6-DOF Hand Pose Tracking System for VR
Technologies 2017, 5(3), 49; doi:10.3390/technologies5030049 -
Abstract
In this paper, a low cost, wearable six Degree of Freedom (6-DOF) hand pose tracking system is proposed for Virtual Reality applications. It is designed for use with an integrated hand exoskeleton system for kinesthetic haptic feedback. The tracking system consists of an
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In this paper, a low cost, wearable six Degree of Freedom (6-DOF) hand pose tracking system is proposed for Virtual Reality applications. It is designed for use with an integrated hand exoskeleton system for kinesthetic haptic feedback. The tracking system consists of an Infrared (IR) based optical tracker with low cost mono-camera and inertial and magnetic measurement unit. Image processing is done on LabVIEW software to extract the 3-DOF position from two IR targets and Magdwick filter has been implemented on Mbed LPC1768 board to obtain orientation data. Six DOF hand tracking outputs filtered and synchronized on LabVIEW software are then sent to the Unity Virtual environment via User Datagram Protocol (UDP) stream. Experimental results show that this low cost and compact system has a comparable performance of minimal Jitter with position and orientation Root Mean Square Error (RMSE) of less than 0.2 mm and 0.15 degrees, respectively. Total Latency of the system is also less than 40 ms. Full article
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