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  • 1.
    Abtahi, Farhad
    et al.
    KTH, Skolan för teknik och hälsa (STH), Medicinsk teknik, Medicinska sensorer, signaler och system.
    Snäll, Jonatan
    KTH, Skolan för teknik och hälsa (STH).
    Aslamy, Benjamin
    KTH, Skolan för teknik och hälsa (STH).
    Abtahi, Shirin
    KTH, Skolan för teknik och hälsa (STH).
    Seoane, Fernando
    KTH, Skolan för teknik och hälsa (STH), Medicinsk teknik, Medicinska sensorer, signaler och system. University of Boras, Sweden.
    Lindecrantz, Kaj
    KTH, Skolan för teknik och hälsa (STH), Medicinsk teknik, Medicinska sensorer, signaler och system. Karolinska Institute, Sweden.
    Biosignal PI, an Affordable Open-Source ECG and Respiration Measurement System2014Inngår i: Sensors, ISSN 1424-8220, E-ISSN 1424-8220, Vol. 15, nr 1, s. 93-109Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Bioimedical pilot projects e.g., telemedicine, homecare, animal and human trials usually involve several physiological measurements. Technical development of these projects is time consuming and in particular costly. A versatile but affordable biosignal measurement platform can help to reduce time and risk while keeping the focus on the important goal and making an efficient use of resources. In this work, an affordable and open source platform for development of physiological signals is proposed. As a first step an 8–12 leads electrocardiogram (ECG) and respiration monitoring system is developed. Chips based on iCoupler technology have been used to achieve electrical isolation as required by IEC 60601 for patient safety. The result shows the potential of this platform as a base for prototyping compact, affordable, and medically safe measurement systems. Further work involves both hardware and software development to develop modules. These modules may require development of front-ends for other biosignals or just collect data wirelessly from different devices e.g., blood pressure, weight, bioimpedance spectrum, blood glucose, e.g., through Bluetooth. All design and development documents, files and source codes will be available for non-commercial use through project website, BiosignalPI.org.

    Fulltekst (pdf)
    fulltext
  • 2.
    Atefi, Seyed Reza
    et al.
    KTH, Skolan för teknik och hälsa (STH), Medicinsk teknik, Medicinska sensorer, signaler och system.
    Seoane, Fernando
    KTH, Skolan för teknik och hälsa (STH), Medicinsk teknik, Medicinska sensorer, signaler och system.
    Thorlin, Thorleif
    Lindecrantz, Kaj
    KTH, Skolan för teknik och hälsa (STH), Medicinsk teknik, Medicinska sensorer, signaler och system.
    Stroke Damage Detection Using Classification Trees on Electrical Bioimpedance Cerebral Spectroscopy Measurements2013Inngår i: Sensors, ISSN 1424-8220, E-ISSN 1424-8220, Vol. 13, nr 8, s. 10074-10086Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    After cancer and cardio-vascular disease, stroke is the third greatest cause of death worldwide. Given the limitations of the current imaging technologies used for stroke diagnosis, the need for portable non-invasive and less expensive diagnostic tools is crucial. Previous studies have suggested that electrical bioimpedance (EBI) measurements from the head might contain useful clinical information related to changes produced in the cerebral tissue after the onset of stroke. In this study, we recorded 720 EBI Spectroscopy (EBIS) measurements from two different head regions of 18 hemispheres of nine subjects. Three of these subjects had suffered a unilateral haemorrhagic stroke. A number of features based on structural and intrinsic frequency-dependent properties of the cerebral tissue were extracted. These features were then fed into a classification tree. The results show that a full classification of damaged and undamaged cerebral tissue was achieved after three hierarchical classification steps. Lastly, the performance of the classification tree was assessed using Leave-One-Out Cross Validation (LOO-CV). Despite the fact that the results of this study are limited to a small database, and the observations obtained must be verified further with a larger cohort of patients, these findings confirm that EBI measurements contain useful information for assessing on the health of brain tissue after stroke and supports the hypothesis that classification features based on Cole parameters, spectral information and the geometry of EBIS measurements are useful to differentiate between healthy and stroke damaged brain tissue.

  • 3.
    Bagula, Antoine
    et al.
    University of Cape Town.
    Inggs, Gordon
    University of Cape Town.
    Scott, Simon
    University of Cape Town.
    Zennaro, Marco
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Kommunikation: Infrastruktur och tjänster, Telekommunikationssystem, TSLab.
    On the Relevance of Using Open Wireless Sensor Networks in Environment Monitoring2009Inngår i: Sensors, ISSN 1424-8220, E-ISSN 1424-8220, Vol. 9, nr 6, s. 4845-4868Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    This paper revisits the problem of the readiness for field deployments of wireless sensor networks by assessing the relevance of using Open Hardware and Software motes for environment monitoring. We propose a new prototype wireless sensor network that fine-tunes SquidBee motes to improve the life-time and sensing performance of an environment monitoring system that measures temperature, humidity and luminosity. Building upon two outdoor sensing scenarios, we evaluate the performance of the newly proposed energy-aware prototype solution in terms of link quality when expressed by the Received Signal Strength, Packet Loss and the battery lifetime. The experimental results reveal the relevance of using the Open Hardware and Software motes when setting up outdoor wireless sensor networks.

  • 4.
    Belloni, Valeria
    et al.
    Sapienza Univ Rome, Geodesy & Geomat Div, DICEA, I-00184 Rome, Italy..
    Ravanelli, Roberta
    Sapienza Univ Rome, Geodesy & Geomat Div, DICEA, I-00184 Rome, Italy..
    Nascetti, Andrea
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Samhällsplanering och miljö, Geoinformatik.
    Di Rita, Martina
    Sapienza Univ Rome, Geodesy & Geomat Div, DICEA, I-00184 Rome, Italy..
    Mattei, Domitilla
    Sapienza Univ Rome, Dept Struct & Geotech Engn, I-00184 Rome, Italy..
    Crespi, Mattia
    Sapienza Univ Rome, Geodesy & Geomat Div, DICEA, I-00184 Rome, Italy..
    py2DIC: A New Free and Open Source Software for Displacement and Strain Measurements in the Field of Experimental Mechanics2019Inngår i: Sensors, ISSN 1424-8220, E-ISSN 1424-8220, Vol. 19, nr 18, artikkel-id 3832Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Thanks to the advances in computer power, memory storage and the availability of low-cost and high resolution digital cameras, Digital Image Correlation (DIC) is currently one of the most used optical and non-contact techniques for measuring material deformations. A free and open source 2D DIC software, named py2DIC, was developed at the Geodesy and Geomatics Division of the Sapienza University of Rome. Implemented in Python, the software is based on the template matching method and computes the 2D displacements and strains of samples subjected to mechanical loading. In this work, the potentialities of py2DIC were evaluated by processing two different sets of experimental data and comparing the results with other three well known DIC software packages Ncorr, Vic-2D and DICe. Moreover, an accuracy assessment was performed comparing the results with the values independently measured by a strain gauge fixed on one of the samples. The results demonstrate the possibility of successfully characterizing the deformation mechanism of the investigated materials, highlighting the pros and cons of each software package.

  • 5.
    Cheng, Xiaogang
    et al.
    KTH, Skolan för elektroteknik och datavetenskap (EECS). Nanjing Univ Posts & Telecommun, Coll Telecommun & Informat Engn, Nanjing 210003, Jiangsu, Peoples R China.;Umea Univ, Dept Appl Phys & Elect, S-90187 Umea, Sweden.
    Yang, Bin
    Umea Univ, Dept Appl Phys & Elect, S-90187 Umea, Sweden.;Xian Univ Architecture & Technol, Sch Environm & Municipal Engn, Xian 710055, Shaanxi, Peoples R China..
    Liu, Guoqing
    Nanjing Tech Univ, Sch Phys & Math Sci, Nanjing 211800, Jiangsu, Peoples R China..
    Olofsson, Thomas
    Umea Univ, Dept Appl Phys & Elect, S-90187 Umea, Sweden..
    Li, Haibo
    KTH, Skolan för elektroteknik och datavetenskap (EECS). Nanjing Univ Posts & Telecommun, Coll Telecommun & Informat Engn, Nanjing 210003, Jiangsu, Peoples R China..
    A Total Bounded Variation Approach to Low Visibility Estimation on Expressways2018Inngår i: Sensors, ISSN 1424-8220, E-ISSN 1424-8220, Vol. 18, nr 2, artikkel-id 392Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Low visibility on expressways caused by heavy fog and haze is a main reason for traffic accidents. Real-time estimation of atmospheric visibility is an effective way to reduce traffic accident rates. With the development of computer technology, estimating atmospheric visibility via computer vision becomes a research focus. However, the estimation accuracy should be enhanced since fog and haze are complex and time-varying. In this paper, a total bounded variation (TBV) approach to estimate low visibility (less than 300 m) is introduced. Surveillance images of fog and haze are processed as blurred images (pse udo-blurred images), while the surveillance images at selected road points on sunny days are handled as clear images, when considering fog and haze as noise superimposed on the clear images. By combining image spectrum and TBV, the features of foggy and hazy images can be extracted. The extraction results are compared with features of images on sunny days. Firstly, the low visibility surveillance images can be filtered out according to spectrum features of foggy and hazy images. For foggy and hazy images with visibility less than 300 m, the high-frequency coefficient ratio of Fourier (discrete cosine) transform is less than 20%, while the low-frequency coefficient ratio is between 100% and 120%. Secondly, the relationship between TBV and real visibility is established based on machine learning and piecewise stationary time series analysis. The established piecewise function can be used for visibility estimation. Finally, the visibility estimation approach proposed is validated based on real surveillance video data. The validation results are compared with the results of image contrast model. Besides, the big video data are collected from the Tongqi expressway, Jiangsu, China. A total of 1,782,000 frames were used and the relative errors of the approach proposed are less than 10%.

  • 6.
    Cuartero, Maria
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Tillämpad fysikalisk kemi.
    Parrilla, Marc
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Tillämpad fysikalisk kemi.
    Crespo, Gaston A.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Tillämpad fysikalisk kemi.
    Wearable Potentiometric Sensors for Medical Applications2019Inngår i: Sensors, ISSN 1424-8220, E-ISSN 1424-8220, Vol. 19, nr 2, artikkel-id 363Artikkel, forskningsoversikt (Fagfellevurdert)
    Abstract [en]

    Wearable potentiometric sensors have received considerable attention owing to their great potential in a wide range of physiological and clinical applications, particularly involving ion detection in sweat. Despite the significant progress in the manner that potentiometric sensors are integrated in wearable devices, in terms of materials and fabrication approaches, there is yet plenty of room for improvement in the strategy adopted for the sample collection. Essentially, this involves a fluidic sampling cell for continuous sweat analysis during sport performance or sweat accumulation via iontophoresis induction for one-spot measurements in medical settings. Even though the majority of the reported papers from the last five years describe on-body tests of wearable potentiometric sensors while the individual is practicing a physical activity, the medical utilization of these devices has been demonstrated on very few occasions and only in the context of cystic fibrosis diagnosis. In this sense, it may be important to explore the implementation of wearable potentiometric sensors into the analysis of other biofluids, such as saliva, tears and urine, as herein discussed. While the fabrication and uses of wearable potentiometric sensors vary widely, there are many common issues related to the analytical characterization of such devices that must be consciously addressed, especially in terms of sensor calibration and the validation of on-body measurements. After the assessment of key wearable potentiometric sensors reported over the last five years, with particular attention paid to those for medical applications, the present review offers tentative guidance regarding the characterization of analytical performance as well as analytical and clinical validations, thereby aiming at generating debate in the scientific community to allow for the establishment of well-conceived protocols.

  • 7.
    Gomez-Espinosa, Alfonso
    et al.
    Tecnol Monterrey, Escuela Ingn & Ciencias, Ave Epigmenio Gonzalez 500, Fracc San Pablo 76130, Queretaro, Mexico..
    Sundin, Roberto Castro
    KTH.
    Loidi Eguren, Ion
    Univ Mondragon, Escuela Politecn Super, Pais Vasco 20500, Spain..
    Cuan-Urquizo, Enrique
    Tecnol Monterrey, Escuela Ingn & Ciencias, Ave Epigmenio Gonzalez 500, Fracc San Pablo 76130, Queretaro, Mexico..
    Trevino-Quintanilla, Cecilia D.
    Tecnol Monterrey, Escuela Ingn & Ciencias, Ave Epigmenio Gonzalez 500, Fracc San Pablo 76130, Queretaro, Mexico..
    Neural Network Direct Control with Online Learning for Shape Memory Alloy Manipulators2019Inngår i: Sensors, ISSN 1424-8220, E-ISSN 1424-8220, Vol. 19, nr 11, artikkel-id 2576Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    New actuators and materials are constantly incorporated into industrial processes, and additional challenges are posed by their complex behavior. Nonlinear hysteresis is commonly found in shape memory alloys, and the inclusion of a suitable hysteresis model in the control system allows the controller to achieve a better performance, although a major drawback is that each system responds in a unique way. In this work, a neural network direct control, with online learning, is developed for position control of shape memory alloy manipulators. Neural network weight coefficients are updated online by using the actuator position data while the controller is applied to the system, without previous training of the neural network weights, nor the inclusion of a hysteresis model. A real-time, low computational cost control system was implemented; experimental evaluation was performed on a 1-DOF manipulator system actuated by a shape memory alloy wire. Test results verified the effectiveness of the proposed control scheme to control the system angular position, compensating for the hysteretic behavior of the shape memory alloy actuator. Using a learning algorithm with a sine wave as reference signal, a maximum static error of 0.83 degrees was achieved when validated against several set-points within the possible range.

  • 8.
    Karlsson, Mikael
    et al.
    RISE Res Inst Sweden AB, Box 1070, SE-16425 Kista, Sweden.;Pamitus AB, Timotejvagen 1, SE-35253 Vaxjo, Sweden..
    Strandqvist, Carl
    Swedish Natl Forens Ctr, SE-58194 Linkoping, Sweden..
    Jussi, Johnny Israelsson
    KTH, Centra, Science for Life Laboratory, SciLifeLab. KTH, Skolan för teknikvetenskap (SCI), Tillämpad fysik. RISE Res Inst Sweden AB, Box 1070, SE-16425 Kista, Sweden..
    Oberg, Olof
    RISE Res Inst Sweden AB, Box 1070, SE-16425 Kista, Sweden..
    Petermann, Ingemar
    RISE Res Inst Sweden AB, Box 1070, SE-16425 Kista, Sweden..
    Elmlund, Louise
    Swedish Natl Forens Ctr, SE-58194 Linkoping, Sweden..
    Dunne, Simon
    Swedish Natl Forens Ctr, SE-58194 Linkoping, Sweden..
    Fu, Ying
    KTH, Skolan för teknikvetenskap (SCI), Tillämpad fysik. KTH, Centra, Science for Life Laboratory, SciLifeLab. Royal Inst Technol, Sci Life Lab, Dept Appl Phys, SE-17121 Solna, Sweden..
    Wang, Qin
    RISE Res Inst Sweden AB, Box 1070, SE-16425 Kista, Sweden..
    Chemical Sensors Generated on Wafer-Scale Epitaxial Graphene for Application to Front-Line Drug Detection2019Inngår i: Sensors, ISSN 1424-8220, E-ISSN 1424-8220, Vol. 19, nr 10, artikkel-id 2214Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Generation of large areas of graphene possessing high quality and uniformity will be a critical factor if graphene-based devices/sensors are to be commercialized. In this work, epitaxial graphene on a 2" SiC wafer was used to fabricate sensors for the detection of illicit drugs (amphetamine or cocaine). The main target application is on-site forensic detection where there is a high demand for reliable and cost-efficient tools. The sensors were designed and processed with specially configured metal electrodes on the graphene surface by utilizing a series of anchors where the metal contacts are directly connected on the SiC substrate. This has been shown to improve adhesion of the electrodes and decrease the contact resistance. A microfluidic system was constructed to pump solutions over the defined graphene surface that could then act as a sensor area and react with the target drugs. Several prototypic systems were tested where non-covalent interactions were used to localize the sensing components (antibodies) within the measurement cell. The serendipitous discovery of a wavelength-dependent photoactivity for amphetamine and a range of its chemical analogs, however, limited the general application of these prototypic systems. The experimental results reveal that the drug molecules interact with the graphene in a molecule dependent manner based upon a balance of -stacking interaction of the phenyl ring with graphene (p-doping) and the donation of the amine nitrogens lone pair electrons into the *-system of graphene (n-doping).

  • 9.
    Lu, Ke
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH). Institute of Environmental Medicine, Karolinska Institutet, Solnavägen 1, 171 77 Solna, Sweden.
    Yang, Liyun
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Medicinteknik och hälsosystem, Ergonomi.
    Seoane, F.
    Abtahi, Farhad
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH). Institute of Environmental Medicine, Karolinska Institutet, Solnavägen 1, 171 77 Solna, Sweden.
    Forsman, Mikael
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Medicinteknik och hälsosystem, Ergonomi. Institute of Environmental Medicine, Karolinska Institutet, Solnavägen 1, 171 77 Solna, Sweden.
    Lindecrantz, K.
    Fusion of heart rate, respiration and motion measurements from a wearable sensor system to enhance energy expenditure estimation2018Inngår i: Sensors, ISSN 1424-8220, E-ISSN 1424-8220, Vol. 18, nr 9, artikkel-id 3092Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    This paper presents a new method that integrates heart rate, respiration, and motion information obtained from a wearable sensor system to estimate energy expenditure. The system measures electrocardiography, impedance pneumography, and acceleration from upper and lower limbs. A multilayer perceptron neural network model was developed, evaluated, and compared to two existing methods, with data from 11 subjects (mean age, 27 years, range, 21–65 years) who performed a 3-h protocol including submaximal tests, simulated work tasks, and periods of rest. Oxygen uptake was measured with an indirect calorimeter as a reference, with a time resolution of 15 s. When compared to the reference, the new model showed a lower mean absolute error (MAE = 1.65 mL/kg/min, R2 = 0.92) than the two existing methods, i.e., the flex-HR method (MAE = 2.83 mL/kg/min, R2 = 0.75), which uses only heart rate, and arm-leg HR+M method (MAE = 2.12 mL/kg/min, R2 = 0.86), which uses heart rate and motion information. As indicated, this new model may, in combination with a wearable system, be useful in occupational and general health applications. 

  • 10. Ludovici, Alessandro
    et al.
    Di Marco, Piergiuseppe
    KTH, Skolan för elektro- och systemteknik (EES), Reglerteknik.
    Calveras, Anna
    Johansson, Karl H.
    KTH, Skolan för elektro- och systemteknik (EES), Reglerteknik.
    Analytical Model of Large Data Transactions in CoAP Networks2014Inngår i: Sensors, ISSN 1424-8220, E-ISSN 1424-8220, Vol. 14, nr 8, s. 15610-15638Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    We propose a novel analytical model to study fragmentation methods in wireless sensor networks adopting the Constrained Application Protocol (CoAP) and the IEEE 802.15.4 standard for medium access control (MAC). The blockwise transfer technique proposed in CoAP and the 6LoWPAN fragmentation are included in the analysis. The two techniques are compared in terms of reliability and delay, depending on the traffic, the number of nodes and the parameters of the IEEE 802.15.4 MAC. The results are validated trough Monte Carlo simulations. To the best of our knowledge this is the first study that evaluates and compares analytically the performance of CoAP blockwise transfer and 6LoWPAN fragmentation. A major contribution is the possibility to understand the behavior of both techniques with different network conditions. Our results show that 6LoWPAN fragmentation is preferable for delay-constrained applications. For highly congested networks, the blockwise transfer slightly outperforms 6LoWPAN fragmentation in terms of reliability.

  • 11.
    Löfhede, Johan
    et al.
    University of Borås.
    Seoane, Fernando
    KTH, Skolan för teknik och hälsa (STH), Medicinska sensorer, signaler och system (MSSS).
    Thordstein, Magnus
    Göteborg Universitet .
    Textile Electrodes for EEG Recording: A Pilot Study2012Inngår i: Sensors, ISSN 1424-8220, E-ISSN 1424-8220, Vol. 12, nr 12, s. 16907-16919Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The overall aim of our research is to develop a monitoring system for neonatal intensive care units. Long-term EEG monitoring in newborns require that the electrodes don’t harm the sensitive skin of the baby, an especially relevant feature for premature babies. Our approach to EEG monitoring is based on several electrodes distributed over the head of the baby, and since the weight of the head always will be on some of them, any type of hard electrode will inevitably cause a pressure-point that can irritate the skin. Therefore, we propose the use of soft conductive textiles as EEG electrodes, primarily for neonates, but also for other kinds of unobtrusive long-term monitoring. In this paper we have tested two types of textile electrodes on five healthy adults and compared them to standard high quality electrodes. The acquired signals were compared with respect to morphology, frequency distribution, spectral coherence, correlation and power line interference sensitivity, and the signals were found to be similar in most respects. The good measurement performance exhibited by the textile electrodes indicates that they are feasible candidates for EEG recording, opening the door for long-term EEG monitoring applications.

  • 12. Mohino-Herranz, Inma
    et al.
    Gil-Pita, Roberto
    Ferreira, Javier
    KTH, Skolan för teknik och hälsa (STH), Medicinsk teknik, Medicinska sensorer, signaler och system. University of Boras, Boras, Sweden.
    Rosa-Zurera, Manuel
    Seoane, Fernando
    KTH, Skolan för teknik och hälsa (STH), Medicinsk teknik, Medicinska sensorer, signaler och system. University of Boras, Boras, Sweden.
    Assessment of Mental, Emotional and Physical Stress through Analysis of Physiological Signals Using Smartphones2015Inngår i: Sensors, ISSN 1424-8220, E-ISSN 1424-8220, Vol. 15, nr 10, s. 25607-25627Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Determining the stress level of a subject in real time could be of special interest in certain professional activities to allow the monitoring of soldiers, pilots, emergency personnel and other professionals responsible for human lives. Assessment of current mental fitness for executing a task at hand might avoid unnecessary risks. To obtain this knowledge, two physiological measurements were recorded in this work using customized non-invasive wearable instrumentation that measures electrocardiogram (ECG) and thoracic electrical bioimpedance (TEB) signals. The relevant information from each measurement is extracted via evaluation of a reduced set of selected features. These features are primarily obtained from filtered and processed versions of the raw time measurements with calculations of certain statistical and descriptive parameters. Selection of the reduced set of features was performed using genetic algorithms, thus constraining the computational cost of the real-time implementation. Different classification approaches have been studied, but neural networks were chosen for this investigation because they represent a good tradeoff between the intelligence of the solution and computational complexity. Three different application scenarios were considered. In the first scenario, the proposed system is capable of distinguishing among different types of activity with a 21.2% probability error, for activities coded as neutral, emotional, mental and physical. In the second scenario, the proposed solution distinguishes among the three different emotional states of neutral, sadness and disgust, with a probability error of 4.8%. In the third scenario, the system is able to distinguish between low mental load and mental overload with a probability error of 32.3%. The computational cost was calculated, and the solution was implemented in commercially available Android-based smartphones. The results indicate that execution of such a monitoring solution is negligible compared to the nominal computational load of current smartphones.

  • 13.
    Pastuhoff, Markus
    et al.
    KTH, Skolan för teknikvetenskap (SCI), Mekanik. KTH, Skolan för industriell teknik och management (ITM), Centra, Competence Center for Gas Exchange (CCGEx).
    Tillmark, Nils
    KTH, Skolan för teknikvetenskap (SCI), Mekanik. KTH, Skolan för industriell teknik och management (ITM), Centra, Competence Center for Gas Exchange (CCGEx).
    Alfredsson, P. Henrik
    KTH, Skolan för teknikvetenskap (SCI), Mekanik. KTH, Skolan för industriell teknik och management (ITM), Centra, Competence Center for Gas Exchange (CCGEx).
    Measuring surface pressure on rotating compressor blades using pressure sensitive paint2016Inngår i: Sensors, ISSN 1424-8220, E-ISSN 1424-8220, Vol. 16, nr 3, artikkel-id 344Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Pressure sensitive paint (PSP) was used to measure pressure on the blades of a radial compressor with a 51 mm inlet diameter rotating at speeds up to 50 krpm using the so called lifetime method. A diode laser with a scanning-mirror system was used to illuminate the paint and the luminescent lifetime was registered using a photo multiplier. With the described technique the surface-pressure fields were acquired for eight points in the compressor map, useful for general understanding of the flow field and for CFD validation. The PSP was of so called fast type, which makes it possible to observe pressure variations with frequencies up to several kHz. Through frequency spectrum analysis we were able to detect the pulsating flow frequency when the compressor was driven to surge.

  • 14.
    Sakr, Mahmoud A.
    et al.
    AUC, Grad Program Nanotechnol, New Cairo 11835, Egypt.;AUC, Dept Mech Engn, New Cairo 11835, Egypt..
    Elgammal, Karim
    KTH, Skolan för teknikvetenskap (SCI), Tillämpad fysik. KTH, Centra, SeRC - Swedish e-Science Research Centre.
    Delin, Anna
    KTH, Skolan för teknikvetenskap (SCI), Tillämpad fysik. KTH, Centra, SeRC - Swedish e-Science Research Centre. Uppsala University, Box 516, Uppsala, SE-75120, Sweden.
    Serry, Mohamed
    AUC, Dept Mech Engn, New Cairo 11835, Egypt..
    Performance-Enhanced Non-Enzymatic Glucose Sensor Based on Graphene-Heterostructure2020Inngår i: Sensors, ISSN 1424-8220, E-ISSN 1424-8220, Vol. 20, nr 1, artikkel-id 145Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Non-enzymatic glucose sensing is a crucial field of study because of the current market demand. This study proposes a novel design of glucose sensor with enhanced selectivity and sensitivity by using graphene Schottky diodes, which is composed of graphene (G)/platinum oxide (PtO)/n-silicon (Si) heterostructure. The sensor was tested with different glucose concentrations and interfering solutions to investigate its sensitivity and selectivity. Different structures of the device were studied by adjusting the platinum oxide film thickness to investigate its catalytic activity. It was found that the film thickness plays a significant role in the efficiency of glucose oxidation and hence in overall device sensitivity. 0.8-2 mu A output current was obtained in the case of 4-10 mM with a sensitivity of 0.2 mu A/mM.cm(2). Besides, results have shown that 0.8 mu A and 15 mu A were obtained by testing 4 mM glucose on two different PtO thicknesses, 30 nm and 50 nm, respectively. The sensitivity of the device was enhanced by 150% (i.e., up to 30 mu A/mM.cm(2)) by increasing the PtO layer thickness. This was attributed to both the increase of the number of active sites for glucose oxidation as well as the increase in the graphene layer thickness, which leads to enhanced charge carriers concentration and mobility. Moreover, theoretical investigations were conducted using the density function theory (DFT) to understand the detection method and the origins of selectivity better. The working principle of the sensors puts it in a competitive position with other non-enzymatic glucose sensors. DFT calculations provided a qualitative explanation of the charge distribution across the graphene sheet within a system of a platinum substrate with D-glucose molecules above. The proposed G/PtO/n-Si heterostructure has proven to satisfy these factors, which opens the door for further developments of more reliable non-enzymatic glucometers for continuous glucose monitoring systems.

  • 15.
    Seoane, Fernando
    et al.
    KTH, Skolan för teknik och hälsa (STH), Medicinsk teknik, Medicinska sensorer, signaler och system.
    Ferreira, Javier
    KTH, Skolan för teknik och hälsa (STH), Medicinsk teknik, Medicinska sensorer, signaler och system.
    Alvarez, Lorena
    Buendia, Ruben
    KTH, Skolan för teknik och hälsa (STH), Medicinsk teknik, Medicinska sensorer, signaler och system.
    Ayllon, David
    Llerena, Cosme
    Gil-Pita, Roberto
    Sensorized Garments and Textrode-Enabled Measurement Instrumentation for Ambulatory Assessment of the Autonomic Nervous System Response in the ATREC Project2013Inngår i: Sensors, ISSN 1424-8220, E-ISSN 1424-8220, Vol. 13, nr 7, s. 8997-9015Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Advances in textile materials, technology and miniaturization of electronics for measurement instrumentation has boosted the development of wearable measurement systems. In several projects sensorized garments and non-invasive instrumentation have been integrated to assess on emotional, cognitive responses as well as physical arousal and status of mental stress through the study of the autonomous nervous system. Assessing the mental state of workers under stressful conditions is critical to identify which workers are in the proper state of mind and which are not ready to undertake a mission, which might consequently risk their own life and the lives of others. The project Assessment in Real Time of the Stress in Combatants (ATREC) aims to enable real time assessment of mental stress of the Spanish Armed Forces during military activities using a wearable measurement system containing sensorized garments and textile-enabled non-invasive instrumentation. This work describes the multiparametric sensorized garments and measurement instrumentation implemented in the first phase of the project required to evaluate physiological indicators and recording candidates that can be useful for detection of mental stress. For such purpose different sensorized garments have been constructed: a textrode chest-strap system with six repositionable textrodes, a sensorized glove and an upper-arm strap. The implemented textile-enabled instrumentation contains one skin galvanometer, two temperature sensors for skin and environmental temperature and an impedance pneumographer containing a 1-channel ECG amplifier to record cardiogenic biopotentials. With such combinations of garments and non-invasive measurement devices, a multiparametric wearable measurement system has been implemented able to record the following physiological parameters: heart and respiration rate, skin galvanic response, environmental and peripheral temperature. To ensure the proper functioning of the implemented garments and devices the full series of 12 sets have been functionally tested recording cardiogenic biopotential, thoracic impedance, galvanic skin response and temperature values. The experimental results indicate that the implemented wearable measurement systems operate according to the specifications and are ready to be used for mental stress experiments, which will be executed in the coming phases of the project with dozens of healthy volunteers.

  • 16.
    Seoane, Fernando
    et al.
    KTH, Skolan för teknik och hälsa (STH), Medicinsk teknik, Medicinska sensorer, signaler och system.
    Mohino-Herranz, Inmaculada
    Ferreira, Javier
    KTH, Skolan för teknik och hälsa (STH), Medicinsk teknik, Medicinska sensorer, signaler och system.
    Alvarez, Lorena
    Buendia, Ruben
    KTH, Skolan för teknik och hälsa (STH), Medicinsk teknik, Medicinska sensorer, signaler och system.
    Ayllon, David
    Llerena, Cosme
    Gil-Pita, Roberto
    Wearable Biomedical Measurement Systems for Assessment of Mental Stress of Combatants in Real Time2014Inngår i: Sensors, ISSN 1424-8220, E-ISSN 1424-8220, Vol. 14, nr 4, s. 7120-7141Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The Spanish Ministry of Defense, through its Future Combatant program, has sought to develop technology aids with the aim of extending combatants' operational capabilities. Within this framework the ATREC project funded by the Coincidente program aims at analyzing diverse biometrics to assess by real time monitoring the stress levels of combatants. This project combines multidisciplinary disciplines and fields, including wearable instrumentation, textile technology, signal processing, pattern recognition and psychological analysis of the obtained information. In this work the ATREC project is described, including the different execution phases, the wearable biomedical measurement systems, the experimental setup, the biomedical signal analysis and speech processing performed. The preliminary results obtained from the data analysis collected during the first phase of the project are presented, indicating the good classification performance exhibited when using features obtained from electrocardiographic recordings and electrical bioimpedance measurements from the thorax. These results suggest that cardiac and respiration activity offer better biomarkers for assessment of stress than speech, galvanic skin response or skin temperature when recorded with wearable biomedical measurement systems.

  • 17.
    Seoane, Fernando
    et al.
    Univ Boras, Swedish Sch Text, S-50190 Boras, Sweden.;Karolinska Univ Hosp, Dept Med Care Technol, S-14157 Huddinge, Sweden.;Karolinska Inst, Inst Clin Sci Intervent & Technol, S-14157 Huddinge, Sweden..
    Soroudi, Azadeh
    Univ Boras, Swedish Sch Text, S-50190 Boras, Sweden..
    Lu, Ke
    Chalmers Univ Technol, Dept Elect Engn, S-41296 Gothenburg, Sweden..
    Nilsson, David
    RISE Res Inst Sweden, Box 857, S-50115 Boras, Sweden..
    Nilsson, Marie
    RISE Res Inst Sweden, Box 857, S-50115 Boras, Sweden..
    Abtahi, Farhad
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Medicinteknik och hälsosystem, Ergonomi. Karolinska Inst, Inst Clin Sci Intervent & Technol, S-14157 Huddinge, Sweden.
    Skrifvars, Mikael
    Univ Boras, Swedish Sch Text, S-50190 Boras, Sweden..
    Textile-Friendly Interconnection between Wearable Measurement Instrumentation and Sensorized Garments-Initial Performance Evaluation for Electrocardiogram Recordings2019Inngår i: Sensors, ISSN 1424-8220, E-ISSN 1424-8220, Vol. 19, nr 20, artikkel-id 4426Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The interconnection between hard electronics and soft textiles remains a noteworthy challenge in regard to the mass production of textile-electronic integrated products such as sensorized garments. The current solutions for this challenge usually have problems with size, flexibility, cost, or complexity of assembly. In this paper, we present a solution with a stretchable and conductive carbon nanotube (CNT)-based paste for screen printing on a textile substrate to produce interconnectors between electronic instrumentation and a sensorized garment. The prototype connectors were evaluated via electrocardiogram (ECG) recordings using a sensorized textile with integrated textile electrodes. The ECG recordings obtained using the connectors were evaluated for signal quality and heart rate detection performance in comparison to ECG recordings obtained with standard pre-gelled Ag/AgCl electrodes and direct cable connection to the ECG amplifier. The results suggest that the ECG recordings obtained with the CNT paste connector are of equivalent quality to those recorded using a silver paste connector or a direct cable and are suitable for the purpose of heart rate detection.

  • 18. Si, Zhongwei
    et al.
    Ma, Junyang
    Thobaben, Ragnar
    KTH, Skolan för elektro- och systemteknik (EES), Kommunikationsteori. KTH, Skolan för elektro- och systemteknik (EES), Centra, ACCESS Linnaeus Centre.
    Coded Cooperation for Multiway Relaying in Wireless Sensor Networks2015Inngår i: Sensors, ISSN 1424-8220, E-ISSN 1424-8220, Vol. 15, nr 7, s. 15265-15284Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Wireless sensor networks have been considered as an enabling technology for constructing smart cities. One important feature of wireless sensor networks is that the sensor nodes collaborate in some manner for communications. In this manuscript, we focus on the model of multiway relaying with full data exchange where each user wants to transmit and receive data to and from all other users in the network. We derive the capacity region for this specific model and propose a coding strategy through coset encoding. To obtain good performance with practical codes, we choose spatially-coupled LDPC (SC-LDPC) codes for the coded cooperation. In particular, for the message broadcasting from the relay, we construct multi-edge-type (MET) SC-LDPC codes by repeatedly applying coset encoding. Due to the capacity-achieving property of the SC-LDPC codes, we prove that the capacity region can theoretically be achieved by the proposed MET SC-LDPC codes. Numerical results with finite node degrees are provided, which show that the achievable rates approach the boundary of the capacity region in both binary erasure channels and additive white Gaussian channels.

  • 19. Smith, A. D.
    et al.
    Li, Qi
    Vyas, Agin
    Haque, Mohammad Mazharul
    Wang, Kejian
    Velasco, Andres
    Zhang, Xiaoyan
    Thurakkal, Shameel
    Quellmalz, Arne
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Intelligenta system, Mikro- och nanosystemteknik.
    Niklaus, Frank
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Intelligenta system, Mikro- och nanosystemteknik.
    Gylfason, Kristinn
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Intelligenta system, Mikro- och nanosystemteknik.
    Lundgren, Per
    Enoksson, Peter
    Carbon-Based Electrode Materials for Microsupercapacitors in Self-Powering Sensor Networks: Present and Future Development2019Inngår i: Sensors, ISSN 1424-8220, E-ISSN 1424-8220, Vol. 19, nr 19, artikkel-id 4231Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    There is an urgent need to fulfill future energy demands for micro and nanoelectronics. This work outlines a number of important design features for carbon-based microsupercapacitors, which enhance both their performance and integration potential and are critical for complimentary metal oxide semiconductor (CMOS) compatibility. Based on these design features, we present CMOS-compatible, graphene-based microsupercapacitors that can be integrated at the back end of the line of the integrated circuit fabrication. Electrode materials and their interfaces play a crucial role for the device characteristics. As such, different carbon-based materials are discussed and the importance of careful design of current collector/electrode interfaces is emphasized. Electrode adhesion is an important factor to improve device performance and uniformity. Additionally, doping of the electrodes can greatly improve the energy density of the devices. As microsupercapacitors are engineered for targeted applications, device scaling is critically important, and we present the first steps toward general scaling trends. Last, we outline a potential future integration scheme for a complete microsystem on a chip, containing sensors, logic, power generation, power management, and power storage. Such a system would be self-powering.

  • 20.
    Stankovic, Milos S.
    et al.
    Univ Belgrade, Sch Elect Engn, Innovat Ctr, Belgrade 11120, Serbia.;Vlatacom Inst, Belgrade 11070, Serbia.;Singidunum Univ, Sch Tech Sci, Belgrade 11000, Serbia..
    Stankovic, Srdjan S.
    Vlatacom Inst, Belgrade 11070, Serbia.;Univ Belgrade, Sch Elect Engn, Belgrade 11120, Serbia..
    Johansson, Karl Henrik
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Intelligenta system, Reglerteknik. KTH, Skolan för elektroteknik och datavetenskap (EECS), Centra, ACCESS Linnaeus Centre.
    Beko, Marko
    Univ Lusofona Humanidades & Tecnol, COPELABS, Campo Grande 376, P-1749024 Lisbon, Portugal.;Univ Nova Lisboa, CTS, P-2829516 Monte De Caparica, Caparica, Portugal..
    Camarinha-Matos, Luis M.
    Univ Nova Lisboa, CTS, P-2829516 Monte De Caparica, Caparica, Portugal.;NOVA Univ Lisbon, Fac Sci & Technol, P-2825149 Caparica, Portugal..
    On Consensus-Based Distributed Blind Calibration of Sensor Networks2018Inngår i: Sensors, ISSN 1424-8220, E-ISSN 1424-8220, Vol. 18, nr 11, artikkel-id 4027Artikkel, forskningsoversikt (Fagfellevurdert)
    Abstract [en]

    This paper deals with recently proposed algorithms for real-time distributed blind macro-calibration of sensor networks based on consensus (synchronization). The algorithms are completely decentralized and do not require a fusion center. The goal is to consolidate all of the existing results on the subject, present them in a unified way, and provide additional important analysis of theoretical and practical issues that one can encounter when designing and applying the methodology. We first present the basic algorithm which estimates local calibration parameters by enforcing asymptotic consensus, in the mean-square sense and with probability one (w.p.1), on calibrated sensor gains and calibrated sensor offsets. For the more realistic case in which additive measurement noise, communication dropouts and additive communication noise are present, two algorithm modifications are discussed: one that uses a simple compensation term, and a more robust one based on an instrumental variable. The modified algorithms also achieve asymptotic agreement for calibrated sensor gains and offsets, in the mean-square sense and w.p.1. The convergence rate can be determined in terms of an upper bound on the mean-square error. The case when the communications between nodes is completely asynchronous, which is of substantial importance for real-world applications, is also presented. Suggestions for design of a priori adjustable weights are given. We also present the results for the case in which the underlying sensor network has a subset of (precalibrated) reference sensors with fixed calibration parameters. Wide applicability and efficacy of these algorithms are illustrated on several simulation examples. Finally, important open questions and future research directions are discussed.

  • 21. Stöggl, Thomas
    et al.
    Holst, Anders
    KTH, Skolan för datavetenskap och kommunikation (CSC), Beräkningsbiologi, CB. Swedish Institute of Computer Science, Sweden .
    Jonasson, Arndt
    Andersson, Erik
    Wunsch, Tobias
    Norström, Christer
    Holmberg, Hans-Christer
    Automatic Classification of the Sub-Techniques (Gears) Used in Cross-Country Ski Skating Employing a Mobile Phone2014Inngår i: Sensors, ISSN 1424-8220, E-ISSN 1424-8220, Vol. 14, nr 11, s. 20589-20601Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The purpose of the current study was to develop and validate an automatic algorithm for classification of cross-country (XC) ski-skating gears (G) using Smartphone accelerometer data. Eleven XC skiers (seven men, four women) with regional-to-international levels of performance carried out roller skiing trials on a treadmill using fixed gears (G2left, G2right, G3, G4left, G4right) and a 950-m trial using different speeds and inclines, applying gears and sides as they normally would. Gear classification by the Smartphone (on the chest) and based on video recordings were compared. Formachine-learning, a collective database was compared to individual data. The Smartphone application identified the trials with fixed gears correctly in all cases. In the 950-m trial, participants executed 140 +/- 22 cycles as assessed by video analysis, with the automatic Smartphone application giving a similar value. Based on collective data, gears were identified correctly 86.0% +/- 8.9% of the time, a value that rose to 90.3% +/- 4.1% (P < 0.01) with machine learning from individual data. Classification was most often incorrect during transition between gears, especially to or from G3. Identification was most often correct for skiers who made relatively few transitions between gears. The accuracy of the automatic procedure for identifying G2left, G2right, G3, G4left and G4right was 96%, 90%, 81%, 88% and 94%, respectively. The algorithm identified gears correctly 100% of the time when a single gear was used and 90% of the time when different gears were employed during a variable protocol. This algorithm could be improved with respect to identification of transitions between gears or the side employed within a given gear.

  • 22.
    Su, Hang
    et al.
    Politecn Milan, Dipartimento Elettron Informaz & Bioingn, I-20133 Milan, Italy..
    Qi, Wen
    Politecn Milan, Dipartimento Elettron Informaz & Bioingn, I-20133 Milan, Italy..
    Hu, Yingbai
    Tech Univ Munich, Dept Informat, D-85748 Munich, Germany..
    Sandoval, Juan
    Univ Poitiers, CNRS, ENSMA, Pprime Inst,Dept GMSC,UPR 3346, Poitiers, France..
    Zhang, Longbin
    KTH, Skolan för teknikvetenskap (SCI), Mekanik. KTH, Skolan för teknikvetenskap (SCI), Centra, BioMEx.
    Schmirander, Yunus
    Politecn Milan, Dipartimento Elettron Informaz & Bioingn, I-20133 Milan, Italy..
    Chen, Guang
    Tongji Univ, Coll Automot Engn, Shanghai 201804, Peoples R China..
    Aliverti, Andrea
    Politecn Milan, Dipartimento Elettron Informaz & Bioingn, I-20133 Milan, Italy..
    Knoll, Alois
    Tech Univ Munich, Dept Informat, D-85748 Munich, Germany..
    Ferrigno, Giancarlo
    Politecn Milan, Dipartimento Elettron Informaz & Bioingn, I-20133 Milan, Italy..
    De Momi, Elena
    Politecn Milan, Dipartimento Elettron Informaz & Bioingn, I-20133 Milan, Italy..
    Towards Model-Free Tool Dynamic Identification and Calibration Using Multi-Layer Neural Network2019Inngår i: Sensors, ISSN 1424-8220, E-ISSN 1424-8220, Vol. 19, nr 17Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    In robot control with physical interaction, like robot-assisted surgery and bilateral teleoperation, the availability of reliable interaction force information has proved to be capable of increasing the control precision and of dealing with the surrounding complex environments. Usually, force sensors are mounted between the end effector of the robot manipulator and the tool for measuring the interaction forces on the tooltip. In this case, the force acquired from the force sensor includes not only the interaction force but also the gravity force of the tool. Hence the tool dynamic identification is required for accurate dynamic simulation and model-based control. Although model-based techniques have already been widely used in traditional robotic arms control, their accuracy is limited due to the lack of specific dynamic models. This work proposes a model-free technique for dynamic identification using multi-layer neural networks (MNN). It utilizes two types of MNN architectures based on both feed-forward networks (FF-MNN) and cascade-forward networks (CF-MNN) to model the tool dynamics. Compared with the model-based technique, i.e., curve fitting (CF), the accuracy of the tool identification is improved. After the identification and calibration, a further demonstration of bilateral teleoperation is presented using a serial robot (LWR4+, KUKA, Germany) and a haptic manipulator (SIGMA 7, Force Dimension, Switzerland). Results demonstrate the promising performance of the model-free tool identification technique using MNN, improving the results provided by model-based methods.

  • 23.
    Tomkowski, Robert
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Industriell produktion.
    Sorsa, Aki
    Univ Oulu, Fac Technol, Control Engn Environm & Chem Engn, POB 4300, FI-90014 Oulu, Finland..
    Santa-aho, Suvi
    Tampere Univ, Fac Engn & Nat Sci, POB 589, FI-33014 Tampere, Finland..
    Lundin, Per
    Schlumpf Scandinavia AB, Flygfaltsgatan 2D, S-12830 Skarpnack, Sweden..
    Vippola, Minnamari
    Tampere Univ, Fac Engn & Nat Sci, POB 589, FI-33014 Tampere, Finland..
    Statistical Evaluation of Barkhausen Noise Testing (BNT) for Ground Samples2019Inngår i: Sensors, ISSN 1424-8220, E-ISSN 1424-8220, Vol. 19, nr 21, artikkel-id 4716Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Barkhausen noise testing (BNT) is a nondestructive method for investigating many properties of ferromagnetic materials. The most common application is the monitoring of grinding burns caused by introducing locally high temperatures while grinding. Other features, such as microstructure, residual stress changes, hardening depth, and so forth, can be monitored as well. Nevertheless, because BNT is a method based on a complex magnetoelectric phenomenon, it is not yet standardized. Therefore, there is a need to study the traceability and stability of the measurement method. This study aimed to carry out a statistical analysis of ferromagnetic samples after grinding processes by the use of BNT. The first part of the experiment was to grind samples in different facilities (Sweden and Finland) with similar grinding parameters, different grinding wheels, and different hardness values. The second part was to evaluate measured BNT parameters to determine significant factors affecting BNT signal value. The measurement data from the samples were divided into two different batches according to where they were manufactured. Both grinding batches contained measurement data from three different participants. The main feature for calculation was the root-mean-square (RMS) value. The first processing step was to normalize the RMS values for all the measurements. A standard analysis of variance (ANOVA) was applied for the normalized dataset. The ANOVA showed that the grinding parameters had a significant impact on the BNT signal value, while the other investigated factors (e.g., participant) were negligible. The reasons for this are discussed at the end of the paper.

  • 24.
    Vega-Barbas, Mario
    et al.
    Karolinska Inst, Inst Environm Med, Solnavagen 1, S-17177 Solna, Sweden.
    Diaz-Olivares, Jose A.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Medicinteknik och hälsosystem, Ergonomi.
    Lu, Ke
    Karolinska Inst, Inst Environm Med, Solnavagen 1, S-17177 Solna, Sweden..
    Forsman, Mikael
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Medicinteknik och hälsosystem, Ergonomi. Karolinska Inst, Inst Environm Med, Solnavagen 1, S-17177 Solna, Sweden.
    Seoane, Fernando
    Karolinska Inst, Dept Clin Sci Intervent & Technol, Halsovagen 7, S-14157 Huddinge, Sweden.;Univ Boras, Swedish Sch Text, Allegatan 1, S-50190 Boras, Sweden.;Karolinska Univ Hosp, Dept & T Biomed Engn, S-17176 Solna, Sweden..
    Abtahi, Farhad
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Medicinteknik och hälsosystem, Ergonomi. Karolinska Inst, Inst Environm Med, Solnavagen 1, S-17177 Solna, Sweden.
    P-Ergonomics Platform: Toward Precise, Pervasive, and Personalized Ergonomics using Wearable Sensors and Edge Computing2019Inngår i: Sensors, ISSN 1424-8220, E-ISSN 1424-8220, Vol. 19, nr 5, artikkel-id 1225Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Preventive healthcare has attracted much attention recently. Improving people's lifestyles and promoting a healthy diet and wellbeing are important, but the importance of work-related diseases should not be undermined. Musculoskeletal disorders (MSDs) are among the most common work-related health problems. Ergonomists already assess MSD risk factors and suggest changes in workplaces. However, existing methods are mainly based on visual observations, which have a relatively low reliability and cover only part of the workday. These suggestions concern the overall workplace and the organization of work, but rarely includes individuals' work techniques. In this work, we propose a precise and pervasive ergonomic platform for continuous risk assessment. The system collects data from wearable sensors, which are synchronized and processed by a mobile computing layer, from which exposure statistics and risk assessments may be drawn, and finally, are stored at the server layer for further analyses at both individual and group levels. The platform also enables continuous feedback to the worker to support behavioral changes. The deployed cloud platform in Amazon Web Services instances showed sufficient system flexibility to affordably fulfill requirements of small to medium enterprises, while it is expandable for larger corporations. The system usability scale of 76.6 indicates an acceptable grade of usability.

  • 25.
    Vega-Barbas, Mario
    et al.
    KTH, Skolan för teknik och hälsa (STH), Medicinsk teknik, Medicinska sensorer, signaler och system.
    Pau, Ivan
    Universidad Politecnica de Madrid.
    Martín-Ruiz, Maria Luisa
    Universidad Politecnica de Madrid.
    Seoane, Fernando
    KTH, Skolan för teknik och hälsa (STH), Medicinsk teknik, Medicinska sensorer, signaler och system.
    Adaptive Software Architecture Based on Confident HCI for the Deployment of Sensitive Services in Smart Homes2015Inngår i: Sensors, ISSN 1424-8220, E-ISSN 1424-8220, Vol. 15, nr 4, s. 7294-7322Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Smart spaces foster the development of natural and appropriate forms of human-computer interaction by taking advantage of home customization. The interaction potential of the Smart Home, which is a special type of smart space, is of particular interest in fields in which the acceptance of new technologies is limited and restrictive. The integration of smart home design patterns with sensitive solutions can increase user acceptance. In this paper, we present the main challenges that have been identified in the literature for the successful deployment of sensitive services (e.g., telemedicine and assistive services) in smart spaces and a software architecture that models the functionalities of a Smart Home platform that are required to maintain and support such sensitive services. This architecture emphasizes user interaction as a key concept to facilitate the acceptance of sensitive services by end-users and utilizes activity theory to support its innovative design. The application of activity theory to the architecture eases the handling of novel concepts, such as understanding of the system by patients at home or the affordability of assistive services. Finally, we provide a proof-of-concept implementation of the architecture and compare the results with other architectures from the literature.

1 - 25 of 25
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