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  • 1.
    Abbasi, Ziwar
    et al.
    Högskolan i Borås, Akademin för textil, teknik och ekonomi.
    Bernebrand, Anna
    Högskolan i Borås, Akademin för textil, teknik och ekonomi.
    Projektering av elnätet för ett exploateringsområde2018Självständigt arbete på grundnivå (yrkesexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [sv]

    Det växande invånarantalet i Sverige har under det senaste decenniet lett till ett stort behov av nybyggnationer av bostäder. Till följd av detta har nybyggnationer av bostäder ökat kraftigt. För att bemöta kapacitetsbehovet krävs stora investeringar från elnätsbolagen för att kunna ansluta de nytillkomna bostadsområdena samt för att möjliggöra utbyggnad av ny infrastruktur. Expansionsmöjligheterna som har uppstått i den aktuella kommunen har lett till utbyggnad av elnätet för ett nytt bostadsområde. Syftet med projekteringen är att hitta en rationell lösning för att kunna förse ett exploateringsområde bestående av 19 bostäder med elektricitet. För att uppnå ett önskvärt resultat med projekteringen har företagsriktlinjer och branschstandarder använts. Det projekterade distributionsnätet utformas av radiellt system, vilket innebär att matning enbart sker från ett håll. Distributionsnätet är uppbyggt av två olika fördelningssystem: TN-S och TN-C. Projekteringen omfattar även nätberäkningar som utförts med både optimeringsprogrammet NetBas och även manuellt. De parametrar som har beräknats är spänningsfall, kortslutningsströmmar och utlösningstider. Dimensioneringen av distributionsnätet, som utfördes endast med hjälp av NetBas, resulterade i placering av en nätstation, fem stycken kabelskåp, 0,9 kilometer lågspänningskabel och 0,13 kilometer högspänningskabel. Projektets totala investeringskostnad har approximativt beräknats till 568 000 kronor.

  • 2. Abtahi, F
    et al.
    Seoane, F
    Högskolan i Borås, Institutionen Ingenjörshögskolan.
    Lindecrantz, K
    Högskolan i Borås, Institutionen Ingenjörshögskolan.
    Electrical bioimpedance spectroscopy in time-variant systems: Is undersampling always a problem?2014Ingår i: Journal of Electrical Bioimpedance, ISSN 1891-5469, E-ISSN 1891-5469, Vol. 5, nr 1, s. 28-33Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    During the last decades, Electrical Bioimpedance Spectroscopy (EBIS) has been applied mainly by using the frequency-sweep technique, across a range of many different applications. Traditionally, the tissue under study is considered to be time-invariant and dynamic changes of tissue activity are ignored by treating the changes as a noise source. A new trend in EBIS is simultaneous electrical stimulation with several frequencies, through the application of a multi-sine, rectangular or other waveform. This method can provide measurements fast enough to sample dynamic changes of different tissues, such as cardiac muscle. This high sampling rate comes at a price of reduction in SNR and the increase in complexity of devices. Although the frequency-sweep technique is often inadequate for monitoring the dynamic changes in a variant system, it can be used successfully in applications focused on the time-invariant or slowly-variant part of a system. However, in order to successfully use frequency-sweep EBIS for monitoring time-variant systems, it is paramount to consider the effects of aliasing and especially the folding of higher frequencies, on the desired frequency e.g. DC level. This paper discusses sub-Nyquist sampling of thoracic EBIS measurements and its application in the case of monitoring pulmonary oedema. It is concluded that by considering aliasing, and with proper implementation of smoothing filters, as well as by using random sampling, frequency-sweep EBIS can be used for assessing time-invariant or slowly-variant properties of time-variant biological systems, even in the presence of aliasing. In general, undersampling is not always a problem, but does always require proper consideration.

  • 3.
    Abtahi, Farhad
    et al.
    Karolinska Institutet.
    Anund, Anna
    Fors, Carina
    Seoane, Fernando
    Högskolan i Borås, Akademin för textil, teknik och ekonomi. Högskolan i Borås, Akademin för vård, arbetsliv och välfärd. Karolinska Institutet.
    Lindecrantz, Kaj
    Högskolan i Borås, Akademin för textil, teknik och ekonomi. Karolinska Institutet.
    Association of Drivers’ sleepiness with heart rate variability. A Pilot Study with Drivers on Real Road2017Konferensbidrag (Övrigt vetenskapligt)
  • 4. Abtahi, Farhad
    et al.
    Aslamy, Benjamin
    Boujabir, I
    Seoane, Fernando
    Högskolan i Borås, Institutionen för Vårdvetenskap.
    Lindecrantz, Kaj
    Högskolan i Borås, Institutionen Ingenjörshögskolan.
    An Affordable ECG and Respiration Monitoring System Based on Raspberry PI and ADAS1000: First Step towards Homecare Applications2014Ingår i: 16th Nordic-Baltic Conference on Biomedical Engineering / [ed] Mindedal H., Persson M., Springer International Publishing , 2014, s. 5-8Konferensbidrag (Refereegranskat)
    Abstract [en]

    Homecare is a potential solution for problems associated with an aging population. This may involve several physiological measurements, and hence a flexible but affordable measurement device is needed. In this work, we have designed an ADAS1000-based four-lead electrocardiogram (ECG) and respiration monitoring system. It has been implemented using Raspberry PI as a platform for homecare applications. ADuM chips based on iCoupler technology have been used to achieve electrical isolation as required by IEC 60601 and IEC 60950 for patient safety. The result proved the potential of Raspberry PI for the design of a compact, affordable, and medically safe measurement device. Further work involves developing a more flexible software for collecting measurements from different devices (measuring, e.g., blood pressure, weight, impedance spectroscopy, blood glucose) through Bluetooth or user input and integrating them into a cloud-based homecare system.

  • 5.
    Abtahi, Farhad
    et al.
    Högskolan i Borås, Institutionen för Vårdvetenskap.
    Berndtsson, A
    Högskolan i Borås, Institutionen för Vårdvetenskap.
    Abtahi, Shirin
    Högskolan i Borås, Institutionen för Vårdvetenskap.
    Seoane, Fernando
    Högskolan i Borås, Institutionen för Vårdvetenskap.
    Lindecrantz, Kaj
    KTH.
    Development and preliminary evaluation of an Android based heart rate variability biofeedback system2014Konferensbidrag (Refereegranskat)
    Abstract [en]

    The reduced Heart Rate Variability (HRV) is believed to be associated with several diseases such as congestive heart failure, diabetes and chronic kidney diseases (CKD). In these cases, HRV biofeedback may be a potential intervention method to increase HRV which in turn is beneficial to these patients. In this work, a real-time Android biofeedback application based on a Bluetooth enabled ECG and thoracic electrical bioimpedance (respiration) measurement device has been developed. The system performance and usability have been evaluated in a brief study with eight healthy volunteers. The result demonstrates real-time performance of system and positive effects of biofeedback training session by increased HRV and reduced heart rate. Further development of the application and training protocol is ongoing to investigate duration of training session to find an optimum length and interval of biofeedback sessions to use in potential interventions.

  • 6.
    Agrawal, Tarun Kumar
    et al.
    Högskolan i Borås, Akademin för textil, teknik och ekonomi.
    Kumar, Vijay
    Högskolan i Borås, Akademin för textil, teknik och ekonomi.
    Pal, Rudrajeet
    Högskolan i Borås, Akademin för textil, teknik och ekonomi.
    Blockchain-Based Framework for Traceability – A Case Example of Nonwoven Supply Chain2019Ingår i: EDANA-Nonwovens Innovation Academy 2019, 2019Konferensbidrag (Refereegranskat)
    Abstract [en]

    Supply chain traceability has emerged as a prime requirement for multi-tier supply chains. It not only enables the supply chain visibility but also caters to the consumer requirements related to transparency, quality assurance, and production tracking. Nonwoven supply chain is one such example that particularly requires traceability implementation due to prevailing problems related to information asymmetry and complex supply chain networks. Conversely, it is challenging for supply chain partners to share all the competitive information in the unsecure environment. In this context, in line with Industry 4.0, this study investigates blockchain technology, which uses a shared and secured data infrastructure to keep track of information about assets and requires no central authority to function. It further proposes a blockchain-based traceability framework that explains supply chain partner interaction and network architecture at organizational level and smart contract and transaction validation rules at the operational level. In order to illustrate the application of the framework, the study presents an example of a nonwoven supply chain to track the nonwoven manufacturing and distribution processes. The proposed system can build a technology-based trust among the supply chain actors, where the distributed ledger would be used to store and authenticate of supply chain transactions.

  • 7.
    Axelberg, P.
    et al.
    Högskolan i Borås, Institutionen Ingenjörshögskolan.
    Gu, I.
    Bollen, M.
    Trace of Flicker Sources by using the Quantity of Flicker power.2008Ingår i: IEEE Transactions on Power Delivery, ISSN 0885-8977, E-ISSN 1937-4208, Vol. 23, nr 1, s. 465-471Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Industries that produce flicker are often placed close to each other and connected to the same power grid system. This implies that the measured flicker level at the point of common coupling (PCC) is a result of contribution from a number of different flicker sources. In a mitigation process it is essential to know which one of the flicker sources is the dominant one. We propose a method to determine the flicker propagations and trace the flicker sources by using flicker power measurements. Flicker power is considered as a quantity containing both sign and magnitude. The sign determines if a flicker source is placed downstream or upstream with respect to a given monitoring point and the magnitude is used to determine the propagation of flicker power throughout the power network and to trace the dominant flicker source. This paper covers the theoretical background of flicker power and describes a novel method for calculation of flicker power that can be implemented in a power network analyzer. Also conducted simulations and a field test based on the proposed method will be described in the paper.

  • 8.
    Axelberg, Peter
    Högskolan i Borås, Institutionen Ingenjörshögskolan.
    On Tracing Flicker Sources and Classification of Voltage Disturbances2007Doktorsavhandling, monografi (Övrigt vetenskapligt)
    Abstract [en]

    Developments in measurement technology, communication and data storage have resulted in measurement systems that produce large amount of data. Together with the long existing need for characterizing the performance of the power system this has resulted in demand for automatic and efficient information-extraction methods. The objective of the research work presented in this thesis was therefore to develop new robust methods that extract additional information from voltage and current measurements in power systems. This work has contributed to two specific areas of interest. The first part of the work has been the development of a measurement method that gives information how voltage flicker propagates (with respect to a monitoring point) and how to trace a flicker source. As part of this work the quantity of flicker power has been defined and integrated in a perceptionally relevant measurement method. The method has been validated by theoretical analysis, by simulations, and by two field tests (at low-voltage and at 130-kV level) with results that matched the theory. The conclusion of this part of the work is that flicker power can be used for efficient tracing of a flicker source and to determine how flicker propagates. The second part of the work has been the development of a voltage disturbance classification system based on the statistical learning theory-based Support Vector Machine method. The classification system shows always high classification accuracy when training data and test data originate from the same source. High classification accuracy is also obtained when training data originate from one power network and test data from another. The classification system shows, however, lower performance when training data is synthetic and test data originate from real power networks. It was concluded that it is possible to develop a classification system based on the Support Vector Machine method with “global settings” that can be used at any location without the need to retrain. The conclusion is that the proposed classification system works well and shows sufficiently high classification accuracy when trained on data that originate from real disturbances. However, more research activities are needed in order to generate synthetic data that have statistical characteristics close enough to real disturbances to replace actual recordings as training data.

  • 9.
    Axelberg, Peter
    et al.
    Högskolan i Borås, Institutionen Ingenjörshögskolan.
    Carlsson, Jonny
    Unipower AB.
    Measuring method for deciding direction to a flickering source2003Patent (Övrig (populärvetenskap, debatt, mm))
    Abstract [en]

    Method and arrangement for deciding the direction to a flickering source in relation to a measurement point in an electrical network with alternating current with a network frequency with low-frequency amplitude variations from the flickering source. The method includes the steps: recording an amplitude-modulated current signal having signals that originate from the network frequency and the low-frequency amplitude variations in the current signal; recording an amplitude-modulated voltage signal having signals that originate from the network frequency and the low-frequency amplitude variations in the voltage signal; creating a flicker power with a sign value by multiplication of the low-frequency amplitude variations in the current signal and the low-frequency amplitude variations in the voltage signal, and analyzing the sign value, with the sign value indicating in which direction the flickering source is to be found in relation to the measurement point.

  • 10.
    Axelberg, Peter
    et al.
    Högskolan i Borås, Institutionen Ingenjörshögskolan.
    Carlsson, Jonny
    Unipower AB.
    Mätmetod för bestämning av riktning till flimmerstörkälla2002Patent (Övrig (populärvetenskap, debatt, mm))
  • 11.
    Axelberg, Peter G. V.
    et al.
    Högskolan i Borås, Institutionen Ingenjörshögskolan.
    Bollen, Math H. J.
    Gu, Irene Y. H.
    A Measurement Method for Determining the Direction of Propagation of Flicker and for Tracing a Flicker Source.2007Konferensbidrag (Refereegranskat)
  • 12.
    Axelberg, Peter G. V.
    et al.
    Högskolan i Borås, Institutionen Ingenjörshögskolan.
    Bollen, Math H. J.
    Gu, Irene Y. H.
    Automatic classification of voltage events using the support Vector2007Konferensbidrag (Refereegranskat)
  • 13.
    Axelberg, P.G.V.
    et al.
    Högskolan i Borås, Institutionen Ingenjörshögskolan.
    Gu, Irene Yu-Hua
    Bollen, M.H.J.
    Support Vector Machine for Classification of Voltage Disturbances2007Ingår i: IEEE Transactions on Power Delivery, ISSN 0885-8977, E-ISSN 1937-4208, Vol. 22, nr 3, s. 1297-1303Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The support vector machine (SVM) is a powerful method for statistical classification of data used in a number of different applications. However, the usefulness of the method in a commercial available system is very much dependent on whether the SVM classifier can be pretrained from a factory since it is not realistic that the SVM classifier must be trained by the customers themselves before it can be used. This paper proposes a novel SVM classification system for voltage disturbances. The performance of the proposed SVM classifier is investigated when the voltage disturbance data used for training and testing originated from different sources. The data used in the experiments were obtained from both real disturbances recorded in two different power networks and from synthetic data. The experimental results shown high accuracy in classification with training data from one power network and unseen testing data from another. High accuracy was also achieved when the SVM classifier was trained on data from a real power network and test data originated from synthetic data. A lower accuracy resulted when the SVM classifier was trained on synthetic data and test data originated from the power network.

  • 14. Bollen, M.
    et al.
    Gu, I.
    Axelberg, P.
    Högskolan i Borås, Institutionen Ingenjörshögskolan.
    Styvaktakis, E.
    Classification of Underlying Causes of Power Quality Disturbances: Deterministic versus Statistical Methods.2007Ingår i: EURASIP Journal on Advances in Signal Processing, ISSN 1687-6172, E-ISSN 1687-6180, Vol. 2007, nr 79747, s. 17-Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    This paper presents the two main types of classification methods for power quality disturbances based on underlying causes: deterministic classification, giving an expert system as an example, and statistical classification, with support vector machines as an example. An expert system is suitable when one has limited amount of data and sufficient power system expert knowledge, however its application requires a set of threshold values. Statistical methods are suitable when large amount of data is available for training. Two important issues to guarantee the effectiveness of a classifier, data segmentation and feature extraction, are discussed. Segmentation of a sequence of data recording is pre-processing to partition the data into segments each representing a duration containing either an event or transition between two events. Extraction of features is applied to each segment individually. Some useful features and their effectiveness are then discussed. Some experimental results are included for demonstrating the effectiveness of both systems. Finally, conclusions are given together with the discussion of some future research directions.

  • 15.
    Buendia, Ruben
    et al.
    Högskolan i Borås, Institutionen Ingenjörshögskolan.
    Gil-Pita, Roberto
    Seoane, Fernando
    Högskolan i Borås, Institutionen Ingenjörshögskolan.
    Cole Parameter Estimation from the Modulus of the Electrical Bioimpeadance for Assessment of Body Composition. A Full Spectroscopy Approach2011Ingår i: Journal of Electrical Bioimpedance, ISSN 1891-5469, E-ISSN 1891-5469, Vol. 2, s. 72-78Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Activities around applications of Electrical Bioimpedance Spectroscopy (EBIS) have proliferated in the past decade significantly. Most of these activities have been focused in the analysis of the EBIS measurements, which eventually might enable novel applications. In Body Composition Assessment (BCA), the most common analysis approach currently used in EBIS is based on the Cole function, which most often requires curve fitting. One of the most implemented approaches for obtaining the Cole parameters is performed in the impedance plane through the geometrical properties that the Cole function exhibit in such domain as depressed semi-circle. To fit the measured impedance data to a semi-circle in the impedance plane, obtaining the Cole parameters in an indirect and sequential manner has several drawbacks. Applying a Non-Linear Least Square (NLLS) iterative fitting on the spectroscopy measurement, obtains the Cole parameters considering the frequency information contained in the measurement. In this work, from experimental total right side EBIS measurements, the BCA parameters have been obtained to assess the amount and distribution of whole body fluids. The values for the BCA parameters have been obtained using values for the Cole parameters estimated with both approaches: circular fitting on the impedance plane and NLLS impedance-only fitting. The comparison of the values obtained for the BCA parameters with both methods confirms that the NLLS impedance-only is an effective alternative as Cole parameter estimation method in BCA from EBIS measurements. Using the modulus of the Cole function as the model for the fitting would eliminate the need for performing phase detection in the acquisition process, simplifying the hardware specifications of the measurement instrumentation when implementing a bioimpedance spectrometer.

  • 16. Buendia, Ruben
    et al.
    Seoane, Fernando
    Högskolan i Borås, Institutionen Ingenjörshögskolan.
    Bosaeus, Ingvar
    Gil-Pita, Roberto
    Johannsson, G
    Ellegård, Lars
    Lindecrantz, Kaj
    Högskolan i Borås, Institutionen Ingenjörshögskolan.
    Robustness study of the different immittance spectra and frequency ranges in bioimpedance spectroscopy analysis for assessment of total body composition2014Ingår i: Physiological Measurement, ISSN 0967-3334, E-ISSN 1361-6579, ISSN 0967-3334, Vol. 35, nr 7, s. 1373-Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The estimation of body fluids is a useful and common practice for assessment of disease status and therapy outcomes. Electrical bioimpedance spectroscopy (EBIS) methods are noninvasive, inexpensive and efficient alternatives for determination of body fluids. One of the main source of errors in EBIS measurements in the estimation of body fluids is capacitive coupling. In this paper an analysis of capacitive coupling in EBIS measurements was performed and the robustness of the different immittance spectra against it tested. On simulations the conductance (G) spectrum presented the smallest overall error, among all immittance spectra, in the estimation of the impedance parameters used to estimate body fluids. Afterwards the frequency range of 10–500 kHz showed to be the most robust band of the G spectrum. The accuracy of body fluid estimations from the resulting parameters that utilized G spectrum and parameters provided by the measuring device were tested on EBIS clinical measurements from growth hormone replacement therapy patients against estimations performed with dilution methods. Regarding extracellular fluid, the correlation between each EBIS method and dilution was 0.93 with limits of agreement of 1.06 ± 2.95 l for the device, 1.10 ± 2.94 l for G [10–500 kHz] and 1.04 ± 2.94 l for G [5–1000 kHz]. Regarding intracellular fluid, the correlation between dilution and the device was 0.91, same as for G [10–500 kHz] and 0.92 for G [5–1000 kHz]. Limits of agreement were 0.12 ± 4.46 l for the device, 0.09 ± 4.45 for G [10–500 kHz] and 0.04 ± 4.58 for G [5–1000 kHz]. Such close results between the EBIS methods validate the proposed approach of using G spectrum for initial Cole characterization and posterior clinical estimation of body fluids status.

  • 17. Buendia, Ruben
    et al.
    Seoane, Fernando
    Högskolan i Borås, Institutionen Ingenjörshögskolan.
    Gil-Pita, Roberto
    A Novel Approach for Removing the Hook Effect Artefact from Electrical Bioimpedance Spectroscopy Measurements2009Ingår i: Journal of Physics: Conference Series, Institute of Physics Publishing Ltd. , 2009Konferensbidrag (Refereegranskat)
    Abstract [en]

    Very often in Electrical Bioimpedance (EBI) spectroscopy measurements the presence of stray capacitances creates a measurement artefact commonly known as Hook Effect. Such an artefact creates a hook-alike deviation of the EBI data noticeable when representing the measurement on the impedance plane. Such Hook Effect is noticeable at high frequencies but it also causes a data deviation at lower measurement frequencies. In order to perform any accurate analysis of the EBI spectroscopy data, the influence of the Hook Effect must be removed. An established method to compensate the hook effect is the well known Td compensation, which consist on multiplying the obtained spectrum, Zmeas() by a complex exponential in the form of exp[jTd]. Such a method cannot correct entirely the Hook Effect since the hook-alike deviation occurs a broad frequency range in both magnitude and phase of the measured impedance, and by using a real value for Td. First, a real value only modifies the phase of the measured impedance and second, it can only correct the Hook Effect at a single frequency. In addition, the process to select a value for Td by an iterative process with the aim to obtain the best Cole fitting lacks solid scientific grounds. In this work the Td compensation method is revisited and a modified approach for correcting the Hook Effect that includes a novel method for selecting the correcting values is proposed. The initial validation results confirm that the proposed method entirely corrects the Hook Effect at all frequencies.

  • 18.
    Buendia, Ruben
    et al.
    Chalmers University of Technology.
    Seoane, Fernando
    Högskolan i Borås, Akademin för vård, arbetsliv och välfärd. KTH-School of Technology and Health.
    Lindecrantz, Kaj
    KTH-School of Technology and Health.
    Bosaeus, Ingvar
    University of Gothenburg.
    Gil-Pita, Roberto
    Universidad de Alcala.
    Johannsson, Gudmundur
    University of Gothenburg.
    Ellegård, Lars
    University of Gothenburg.
    Ward, Leigh
    University of Queensland.
    Estimation of body fluids with bioimpedance spectroscopy: state of the art methods and proposal of novel methods2015Ingår i: Physiological Measurement, ISSN 0967-3334, E-ISSN 1361-6579, Vol. 36, nr 10Artikel i tidskrift (Refereegranskat)
  • 19.
    Chen, Wei
    et al.
    Fudan University.
    Augusto, Juan CarlosMiddlesex University.Seoane, FernandoHögskolan i Borås, Akademin för vård, arbetsliv och välfärd. KTH-School of Technology and Health.Ledhocki, FedorSlovak University of Technology.Arends, JohanTechnical University of Technology.Ungureanu, ConstantinHobo Heeze.Wichert, ReinerFraunhofer IGD.
    Recent Advances in Ambient Assisted Living: Bridging Assistive Technologies, e-Health and Personalized Health Care2015Samlingsverk (redaktörskap) (Refereegranskat)
  • 20.
    Cheng, Jingyuan
    et al.
    German Research Center for Artificial Intelligence (DFKI).
    Zhou, Bo
    German Research Center for Artificial Intelligence (DFKI).
    Lukowicz, Paul
    German Research Center for Artificial Intelligence (DFKI).
    Seoane, Fernando
    Högskolan i Borås, Akademin för textil, teknik och ekonomi. Högskolan i Borås, Akademin för vård, arbetsliv och välfärd. Karolinska Institutet.
    Varga, Matija
    ETH Zurich.
    Mehmann, Andreas
    ETH Zurich.
    Chabrecek, Peter
    SEFAR AG.
    Gaschler, Werner
    SEFAR AG.
    Goenner, Karl
    ITV Denkendorf.
    Horter, Hansjürgen
    ITV Denkendorf.
    Schneegass, Stefan
    Hassib, Mariam
    University of Stuttgart.
    Schmidt, Albrecht
    University of Stuttgart.
    Freund, Martin
    University of Passau.
    Zhang, Rui
    University of Passau.
    Amft, Oliver
    University of Passau.
    Textile Building Blocks:Toward Simple, Modularized, and Standardized Smart Textile2017Ingår i: Smart Textiles: Fundamentals, Design, and Interaction, Springer, Cham , 2017, s. 303-331Kapitel i bok, del av antologi (Refereegranskat)
    Abstract [en]

    Textiles are pervasive in our life, covering human body and objects, as well as serving in industrial applications. In its everyday use of individuals, smart textile becomes a promising medium for monitoring, information retrieval, and interaction. While there are many applications in sport, health care, and industry, the state-of-the-art smart textile is still found only in niche markets. To gain mass-market capabilities, we see the necessity of generalizing and modularizing smart textile production and application development, which on the one end lowers the production cost and on the other end enables easy deployment. In this chapter, we demonstrate our initial effort in modularization. By devising types of universal sensing fabrics for conductive and non-conductive patches, smart textile construction from basic, reusable components can be made. Using the fabric blocks, we present four types of sensing modalities, including resistive pressure, capacitive, bioimpedance, and biopotential. In addition, we present a multi-channel textile–electronics interface and various applications built on the top of the basic building blocks by ‘cut and sew’ principle.

  • 21.
    Ferreira Gonzalez, Javier
    Högskolan i Borås, Institutionen Ingenjörshögskolan.
    Textile-enabled Bioimpedance Instrumentation for Personalised Health Monitoring Applications2013Licentiatavhandling, monografi (Övrigt vetenskapligt)
    Abstract [en]

    A growing number of factors, including the costs, technological advancements, an ageing population, and medical errors are leading industrialised countries to invest in research on alternative solutions to improving their health care systems and increasing patients’ life quality. Personal Health System (PHS) solutions envision the use of information and communication technologies that enable a paradigm shift from the traditional hospital-centred healthcare delivery model toward a preventive and person-centred approach. PHS offers the means to follow patient health using wearable, portable or implantable systems that offer ubiquitous, unobtrusive bio-data acquisition, allowing remote access to patient status and treatment monitoring.Electrical Bioimpedance (EBI) technology is a non-invasive, quick and relatively affordable technique that can be used for assessing and monitoring different health conditions, e.g., body composition assessments for nutrition. EBI technology combined with state-of-the-art advances in sensor and textile technology are fostering the implementation of wearable bioimpedance monitors that use functional garments for the implementation of personalised healthcare applications.This research studies the development of a portable EBI spectrometer that can use dry textile electrodes for the assessment of body composition for the purposes of clinical uses. The portable bioimpedance monitor has been developed using the latest advances in system-on-chip technology for bioimpedance spectroscopy instrumentation. The obtained portable spectrometer has been validated against commercial spectrometer that performs total body composition assessment using functional textrode garments.The development of a portable Bioimpedance spectrometer using functional garments and dry textile electrodes for body composition assessment has been shown to be a feasible option. The availability of such measurement systems bring closer the real implementation of personalised healthcare systems.

  • 22.
    Ferreira Gonzalez, Javier
    et al.
    Högskolan i Borås, Institutionen Ingenjörshögskolan.
    Seoane, Fernando
    Högskolan i Borås, Institutionen Ingenjörshögskolan.
    Lindecrantz, Kaj
    Högskolan i Borås, Institutionen Ingenjörshögskolan.
    AD5933-Based Electrical Bioimpedance Spectrometer. Towards Textile-Enabled Applications.2011Konferensbidrag (Refereegranskat)
  • 23.
    Ferreira, Javier
    et al.
    Högskolan i Borås, Institutionen Ingenjörshögskolan.
    Seoane, Fernando
    Högskolan i Borås, Institutionen Ingenjörshögskolan.
    Ansede, Antonio
    Bragos, Ramon
    AD5933-based Spectrometer for Electrical Bioimpedance Applications2010Ingår i: Journal of Physics: Conference Series, Institute of Physics Publishing Ltd. , 2010Konferensbidrag (Refereegranskat)
    Abstract [en]

    To build an Electrical Bioimpedance (EBI) spectrometer using the Impedance Measurement System-On-Chip AD5933 together with a 4-Electrode Analog Front End (4E-AFE) has been proven practicable. Such small measurement devices can make possible several new applications of EBI technology, especially when combined with functional textiles, which can enable wearable applications for personal health and home monitoring. After the implementation and functional validation of the 4E-AFE-enabled spectrometer, the next natural step is to validate for which EBI applications the 4E-AFE-enabled system is suitable. To test the applicability of this novel spectrometer on several EBI applications, 2R1C equivalents models have been experimentally obtained and impedance spectroscopy measurements have been performed with the system under study and with the SFB7 EBI spectrometer manufactured by ImpediMed. The 2R1C circuit parameters have been estimated with the BioImp software from the spectra obtained with both EBI spectrometers and the estimated values have been compared with the original values used in each circuit model implementation. The obtained results indicated that the 4E-AFE-enabled system cannot beat the performance of the SFB7 in accuracy but it performs better in preciseness. In any case the overall performance indicates that the 4E-AFE-enabled system can perform spectroscopy measurements in the frequency range from 5 to 100 kHz.

  • 24.
    Guo, Li
    et al.
    Högskolan i Borås, Institutionen Textilhögskolan.
    Berglin, Lena
    Högskolan i Borås, Institutionen Textilhögskolan.
    Conductive coated force sensor in cargo transportation security system2010Konferensbidrag (Övrigt vetenskapligt)
  • 25.
    Guo, Li
    et al.
    Högskolan i Borås, Institutionen Textilhögskolan.
    Berglin, Lena
    Högskolan i Borås, Institutionen Textilhögskolan.
    Mattila, Heikki
    Högskolan i Borås, Institutionen Textilhögskolan.
    Textile Strain Sensors Characterization- Sensitivity, Linearity, Stability and Hysteresis2010Ingår i: Nordic Textile Journal, nr 2, s. 51-63Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    In this paper 4 different textile based strain sensors for measuring different level of strains were presented. Sensor consist a conductive part formed by coating or weaving technique. Both elastic and inelastic textile substrates were selected to achieve the required stains in applications. Sensor configuration was characterized using a tensile tester and measuring the resistance parallel by microprocessor. A linear working range with transfer function of each sensor was found. Coated sensor gives a good stability, while woven sensor was relative less stable. Inelastic textile substrate reduces the hysteresis error caused by refraction and construction of materials. The sensitivities were between 2.5 to 9 vary with different sensors. This paper finished by a discussion of how to choose sensors with different applications, among which sensor function and processability are most important aspects to be considering.

  • 26.
    Guo, Li
    et al.
    Högskolan i Borås, Institutionen Textilhögskolan.
    Berglin, Lena
    Högskolan i Borås, Institutionen Textilhögskolan.
    Mattila, Heikki
    Högskolan i Borås, Institutionen Textilhögskolan.
    Mehrjerdi, Adib
    Skrifvars, Mikael
    Högskolan i Borås, Institutionen Ingenjörshögskolan.
    Disappearing Sensors. Textile Based Sensors for Monitoring Breathing2011Konferensbidrag (Refereegranskat)
    Abstract [en]

    Textile based sensors were developed and used for remote monitoring of breathing. The breathing is simulated by using a new cyclic tester device. In the simulated a cyclic force is applied along the length of the textile sensor. However due to the morphology of human body, in real situation the sensor is not only under stretching but also under a certain degree of bending. A prototype garment with the sensor situated on the chest area was made. The prototype was worn by 10 persons, and breathing was recorded as the persons were sitting still, walking and jogging. Deep breathing in the supine position and breathing with a method called athletic breathing were used to evaluate the sensor. A testing circuit and a Labview program were made for preliminary test. The sensor is wearable, washable and comfortable. Sensor construction is totally ‘disappearing’ and visualize as printed pattern onto the surface of garment.

  • 27.
    Göbel, Hannes
    et al.
    Högskolan i Borås, Institutionen Handels- och IT-högskolan.
    Cronholm, Stefan
    Högskolan i Borås, Institutionen Handels- och IT-högskolan.
    Seigerroth, Ulf
    Towards an agile method for ITSM self-assessment: A Design Science Research Approach2013Ingår i: Proceedings of ICMLG 2013 The International Conference on Management, Leadership and Governance., ICMLG , 2013Konferensbidrag (Refereegranskat)
    Abstract [en]

    IT Service Management (ITSM) is an expensive field where small and medium sized enterprises (SMEs) need to become more efficient in their ITSM related work in order to cut costs and improve quality. The focus of this paper is to suggest a solution to the scarcity of process improvement methods dedicated to ITSM-processes in SMEs. The solution consists of an agile self-assessment method designed and evaluated in accordance with Design Science Research. The aim of the method is to support SMEs in their attempt to evaluate and improve their quality of ITSM processes. The findings show that the method creates opportunities for organizations to improve their ITSM processes. The method can be used to identify process gaps in comparison to standards for ITSM. It can also be used for benchmarking purposes within an organization as well as it can guide an organization’s improvement efforts. The method also depicts a standard that is easy for SMEs to understand and to use as guidance (with ITSM specific examples). Finally, the method enables SMEs to implement standards for ITSM in a resource-efficient way. Based on empirical evidence from applying the method the conclusion is that the method is useful for the intended target group and that the method agrees well with theories within the field.

  • 28.
    Hallnäs, Lars
    Högskolan i Borås, Institutionen Textilhögskolan.
    Proceedings Ambience112011Konferensbidrag (Refereegranskat)
  • 29. Hopkins, P
    et al.
    Outram, N
    Löfgren, N
    Ofeachor, E. C.
    Rosén, K. G.
    Högskolan i Borås, Institutionen Ingenjörshögskolan.
    A comparative study of fetal heart rate variability analysis techniques2006Konferensbidrag (Refereegranskat)
  • 30. Jiang, Wen jun
    et al.
    Wittek, Peter
    Högskolan i Borås, Institutionen Biblioteks- och informationsvetenskap / Bibliotekshögskolan.
    Zhao, Li
    Gao, Shi Chao
    Adaptive Thresholding with Inverted Triangular Area for Real-Time Detection of the Heart Rate from Photoplethysmogram Traces on a Smartphone2014Konferensbidrag (Refereegranskat)
    Abstract [en]

    Photoplethysmogram (PPG) signals acquired by smartphone cameras are weaker than those acquired by dedicated pulse oximeters. Furthermore, the signals have lower sampling rates, have notches in the waveform and are more severely affected by baseline drift, leading to specific morphological characteristics. This paper introduces a new feature, the inverted triangular area, to address these specific characteristics. The new feature enables real-time adaptive waveform detection using an algorithm of linear time complexity. It can also recognize notches in the waveform and it is inherently robust to baseline drift. An implementation of the algorithm on Android is available for free download. We collected data from 24 volunteers and compared our algorithm in peak detection with two competing algorithms designed for PPG signals, Incremental-Merge Segmentation (IMS) and Adaptive Thresholding (ADT). A sensitivity of 98.0 % and a positive predictive value of 98.8 % were obtained, which were 7.7 % higher than the IMS algorithm in sensitivity, and 8.3 % higher than the ADT algorithm in positive predictive value. The experimental results confirmed the applicability of the proposed method.

  • 31.
    Jiong, Sun
    et al.
    Högskolan i Skövde.
    Billing, Erik
    Högskolan i Skövde.
    Seoane, Fernando
    Högskolan i Borås, Akademin för textil, teknik och ekonomi. Högskolan i Borås, Akademin för vård, arbetsliv och välfärd. Karolinska Institutet.
    Zhou, Bo
    DFKI.
    Högberg, Dan
    Högskolan i Skövde.
    Hemeren, Paul
    Högskolan i Skövde.
    Categories of touch: Classifying human touch using a soft tactile sensor2017Ingår i: The robotic sense of touch: From sensing to understanding, workshop at the IEEE International Conference on Robotics and Automation (ICRA), 29 May, Singapore., 2017Konferensbidrag (Refereegranskat)
  • 32.
    Kapur, Jyoti
    Högskolan i Borås, Akademin för textil, teknik och ekonomi.
    Engaging with Sense of Smell through Textile Interactions2019Ingår i: Distributed, Ambient and Pervasive Interactions: 7th International Conference, DAPI 2019 Held as Part of the 21st HCI International Conference / [ed] Norbert Streitz, Shin’ichi Konomi, Switzerland: Springer, 2019, s. 241-257Konferensbidrag (Refereegranskat)
    Abstract [en]

    This research paper discusses dimension of smell for designing spatial interactions through textiles. The focus in these design examples is combining the sense of touch to actuate the smells. Sense of touch is explored in terms of different tactile sensations that include pressing, rubbing and movement of the body. Through these tactile interactions smells embedded in the textile objects are released. The temporal textile expressions of smells open up for further investigations for designing spaces, as these design examples bring forward the olfactory expressions and proposes frameworks for future research in potential human-computer interactions through our everyday objects and surroundings. The proposal of textile interactions that engage sense of smell and create slow interactions with objects and situations from our daily lives opens up the opportunity to encourage more social interactions within the physical world. These interactions will include computational things, however, in a discreet manner, helping build deep bonds between human to human and human to environment.

  • 33.
    Kontopoulos, E.
    et al.
    CERTH, Thessaloniki, Greece.
    Darányi, Sándor
    Högskolan i Borås, Akademin för bibliotek, information, pedagogik och IT.
    Wittek, Peter
    Högskolan i Borås, Akademin för bibliotek, information, pedagogik och IT.
    Konstantinidis, K.
    CERTH, Thessaloniki, Greece.
    Riga, M.
    CERTH, Thessaloniki, Greece.
    Mitzias, P.
    CERTH, Thessaloniki, Greece.
    Stavropoulos, T.
    CERTH, Thessaloniki, Greece.
    Andreadis, S.
    CERTH, Thessaloniki, Greece.
    Maronidis, A.
    CERTH, Thessaloniki, Greece.
    Karakostas, A.
    CERTH, Thessaloniki, Greece.
    Tachos, S.
    CERTH, Thessaloniki, Greece.
    Kaltsa, V.
    CERTH, Thessaloniki, Greece.
    Tsagiopoulu, M.
    CERTH, Thessaloniki, Greece.
    Avgerinakis, K.
    CERTH, Thessaloniki, Greece.
    Deliverable 4.5: Context-aware Content Interpretation2016Rapport (Refereegranskat)
    Abstract [en]

    The current deliverable summarises the work conducted within task T4.5 of WP4, presenting our proposed approaches for contextualised content interpretation, aimed at gaining insightful contextualised views on content semantics. This is achieved through the adoption of appropriate context-aware semantic models developed within the project, and via enriching the semantic descriptions with background knowledge, deriving thus higher level contextualised content interpretations that are closer to human perception and appraisal needs. More specifically, the main contributions of the deliverable are the following: A theoretical framework using physics as a metaphor to develop different models of evolving semantic content. A set of proof-of-concept models for semantic drifts due to field dynamics, introducing two methods to identify quantum-like (QL) patterns in evolving information searching behaviour, and a QL model akin to particle-wave duality for semantic content classification. Integration of two specific tools, Somoclu for drift detection and Ncpol2spda for entanglement detection. An “energetic” hypothesis accounting for contextualized evolving semantic structures over time. A proposed semantic interpretation framework, integrating (a) an ontological inference scheme based on Description Logics (DL), (b) a rule-based reasoning layer built on SPARQL Inference Notation (SPIN), (c) an uncertainty management framework based on non-monotonic logics. A novel scheme for contextualized reasoning on semantic drift, based on LRM dependencies and OWL’s punning mechanism. An implementation of SPIN rules for policy and ecosystem change management, with the adoption of LRM preconditions and impacts. Specific use case scenarios demonstrate the context under development and the efficiency of the approach. Respective open-source implementations and experimental results that validate all the above.All these contributions are tightly interlinked with the other PERICLES work packages: WP2 supplies the use cases and sample datasets for validating our proposed approaches, WP3 provides the models (LRM and Digital Ecosystem models) that form the basis for our semantic representations of content and context, WP5 provides the practical application of the technologies developed to preservation processes, while the tools and algorithms presented in this deliverable can be deployed in combination with test scenarios, which will be part of the WP6 test beds.

  • 34.
    Kontopoulos, Efstratios
    et al.
    CERTH, Thessaloniki, Greece.
    Riga, Marina
    CERTH, Thessaloniki, Greece.
    Mitzias, P.
    CERTH, Thessaloniki, Greece.
    Andreadis, S.
    CERTH, Thessaloniki, Greece.
    Stavropoulos, T.
    CERTH, Thessaloniki, Greece.
    Konstantinidis, K.
    CERTH, Thessaloniki, Greece.
    Maronidis, A.
    CERTH, Thessaloniki, Greece.
    Karakostas, A.
    CERTH, Thessaloniki, Greece.
    Tachos, S.
    CERTH, Thessaloniki, Greece.
    Kaltsa, V.
    CERTH, Thessaloniki, Greece.
    Tsagiopoulu, M.
    CERTH, Thessaloniki, Greece.
    Darányi, Sándor
    Högskolan i Borås, Akademin för bibliotek, information, pedagogik och IT.
    Wittek, Peter
    Högskolan i Borås, Akademin för bibliotek, information, pedagogik och IT.
    Gill, A.
    King's College London, UK.
    Tonkin, E. L.
    King's College London, UK.
    Waddington, S.
    King's College London, UK.
    Sauter, Ch.
    King's College London, UK.
    Corubolo, F.
    University of Liverpool, UK.
    PERICLES Deliverable 4.4: Modelling Contextualised Semantics2016Rapport (Refereegranskat)
    Abstract [en]

    The current deliverable summarises the work conducted within task T4.4 of WP4, presenting our proposed models for semantically representing digital content and its respective context – the latter refers to any information coming from the environment of the digital object (DO) that offers a better insight into the object’s status, its  interrelationships with other content items and information about the object’s context of use. Within PERICLES, we refer to the content semantics enriched with the contextual perspective as “contextualised semantics”. The deliverable presents two complementary modelling approaches, based respectively on (a) ontologies and logics, and, (b) multivariate statistics.

  • 35. Kulinska, Maria
    et al.
    Bruniaux, Pascale
    Ainamo, Antti
    Högskolan i Borås, Akademin för textil, teknik och ekonomi.
    VIRTUAL MANNEQUINS AND GARMENT PARAMETRIZATION2016Ingår i: VIRTUAL MANNEQUINS AND GARMENT PARAMETRIZATION, 2016Konferensbidrag (Refereegranskat)
  • 36.
    Kumar, Vijay
    et al.
    Högskolan i Borås, Akademin för textil, teknik och ekonomi. Soochow University China.
    Hallqvist, Carina
    Högskolan i Borås, Akademin för bibliotek, information, pedagogik och IT.
    Ekwall, Daniel
    Högskolan i Borås, Akademin för textil, teknik och ekonomi. Hanken School of Economics, Finland.
    Developing a Framework for Traceability Implementation in the Textile Supply Chain2017Ingår i: Systems, ISSN 2079-8954, Vol. 5, nr 2, artikel-id 33Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Traceability has recently gained considerable attention in the textile industry. Traceability stands for information sharing about a product including the product history, specification, or location. With the involvement of globally dispersed actors in the textile supply chain, ensuring appropriate product quality with timely supplies is crucial for surviving in this industry with ever increasing competition. Hence it is of paramount importance for a supply chain actor to track every product and trace its history in the supply chain. In this context, this paper presents a framework to implement traceability in the textile supply chain. A system approach has been followed, where firstly the usage requirement of traceability is defined, and then a framework for implementing intra-actor or internal traceability and inter-actor or external traceability is discussed. This article further presents a sequential diagram to demonstrate the interaction and information exchange between the actors in the supply chain, when the traceability information is requested. An example is also illustrated for data storage using a relational database management system and information exchange using XML for the textile weaver. Finally, the article discusses challenges and future studies required to implement traceability in the textile supply chain.

  • 37. Kuzmicova, Anezka
    et al.
    Dias, Patricia
    Vogrincic Cepic, Ana
    Albrechtslund, Anne-Mette
    Kotrla Topic, Marina
    Minguez Lopez, Xavier
    Nilsson, Skans Kersti
    Högskolan i Borås, Akademin för bibliotek, information, pedagogik och IT.
    Teixeira-Botelho, Ines
    Social Space in Silent Reading Practices2017Konferensbidrag (Refereegranskat)
  • 38.
    Li, Cai
    et al.
    Cognitiona and Interaction Lab, School of Informatics, University of Skövde, Sweden.
    Bredies, Katharina
    Design Research Lab Berlin.
    Lund, Anja
    Högskolan i Borås, Akademin för textil, teknik och ekonomi.
    Nierstrasz, Vincent
    Högskolan i Borås, Akademin för textil, teknik och ekonomi.
    Hemeren, Paul
    Cognition and Interaction Lab, School of Informatics, University of Skövde, Sweden.
    Högberg, Dan
    School of Engineering Science, University of Skövde, Sweden.
    kNN based Numerical Hand Posture Recognition using a Smart Textile Glove2015Ingår i: Ambient 2015: The Fifth International Conference on Ambient Computing, Applications, Services and Technologies / [ed] Maarten Weyn, 2015, s. 36-41Konferensbidrag (Refereegranskat)
  • 39.
    Lind, Carl Mikael
    et al.
    Division of Ergonomics, KTH Royal Institute of Technology.
    Sandsjö, Leif
    Högskolan i Borås, Akademin för vård, arbetsliv och välfärd.
    Mahdavian, Nafise
    School of Engineering Science; University of Skövde.
    Högberg, Dan
    School of Engineering Science; University of Skövde.
    Hanson, Lars
    School of Engineering Science; University of Skövde.
    Olivares, Jose Antonio Diaz
    Division of Ergonomics, KTH Royal Institute of Technology.
    Yang, Liyun
    Unit of Occupational Medicine, Karolinska Institutet.
    Forsman, Mikael
    Division of Ergonomics, KTH Royal Institute of Technology.
    Prevention of Work-Related Musculoskeletal Disorders Using Smart Workwear – The Smart Workwear Consortium2019Ingår i: International Conference on Human Systems Engineering and Design: Future Trends and Applications: Human Systems Engineering and Design. IHSED 2018. Advances in Intelligent Systems and Computing, vol 876. Springer, Cham / [ed] Ahram T., Karwowski W., Taiar R. (eds), Springer, Cham , 2019, Vol. 876, s. 477-483Konferensbidrag (Övrigt vetenskapligt)
    Abstract [en]

    Adverse work-related physical exposures such as repetitive movements and awkward postures have negative health effects and lead to large financial costs. To address these problems, a multi-disciplinary consortium was formed with the aim of developing an ambulatory system for recording and analyzing risks for musculoskeletal disorders utilizing textile integrated sensors as part of the regular workwear. This paper presents the consortium, the Smart Workwear System, and a case study illustrating its potential to decrease adverse biomechanical exposure by promoting improved work technique.

  • 40. Löfgren, N.
    et al.
    Lindecrantz, Kaj
    Högskolan i Borås, Institutionen Ingenjörshögskolan.
    Flisberg, A.
    Bågenholm, R.
    Kjellmer, I.
    Thordstein, M.
    Spectral Distance for ARMA Models Applied to Electroencephalogram for Early Detection of Hypoxia.2006Ingår i: Journal of Neural Engineering, ISSN 1741-2560, E-ISSN 1741-2552, Vol. 3, nr 3, s. 227-234Artikel i tidskrift (Refereegranskat)
  • 41.
    Löfhede, Johan
    Högskolan i Borås, Institutionen Ingenjörshögskolan.
    The EEG of the neonatal brain: classification of background activity2009Doktorsavhandling, monografi (Övrigt vetenskapligt)
    Abstract [en]

    The brain requires a continuous supply of oxygen and nutrients, and even a short period of reduced oxygen supply can cause severe and lifelong consequences for the affected individual. The unborn baby is fairly robust, but there are of course limits also for these individuals. The most sensitive and most important organ is the brain. When the brain is deprived of oxygen, a process can start that ultimately may lead to the death of brain cells and irreparable brain damage. This process has two phases; one more or less immediate and one delayed. There is a window of time of up to 24 hours where action can be taken to prevent the delayed secondary damage. One recently clinically available technique is to reduce the metabolism and thereby stop the secondary damage in the brain by cooling the baby. It is important to be able to quickly diagnose hypoxic injuries and to follow the development of the processes in the brain. For this, the electroencephalogram (EEG) is an important tool. The EEG is a voltage signal that originates within the brain and that can be recorded easily and non-invasively at bedside. The signals are, however, highly complex and require special competence to interpret, a competence that typically is not available at the intensive care unit, and particularly not continuously day and night. This thesis addresses the problem of automatic classification of neonatal EEG and proposes methods that would be possible to use in bedside monitoring equipment for neonatal intensive care units. The thesis is a compilation of six papers. The first four deal with the segmentation of pathological signals (burst suppression) from post-asphyctic full term newborn babies. These studies investigate the use of various classification techniques, using both supervised and unsupervised learning. In paper V the scope is widened to include both classification of pathological activity versus activity found in healthy babies as well as application of the segmentation methods on the parts of the EEG signal that are found to be of the pathological type. The use of genetic algorithms for feature selection is also investigated. In paper VI the segmentation methods are applied on signals from pre-term babies to investigate the impact of a certain medication on the brain. The results of this thesis demonstrate ways to improve the monitoring of the brain during intensive care of newborn babies. Hopefully it will someday be implemented in monitoring equipment and help to prevent permanent brain damage in post asphyctic babies.

  • 42.
    Löfhede, Johan
    et al.
    Högskolan i Borås, Institutionen Ingenjörshögskolan.
    Degerman, Johan
    Löfgren, Nils
    Thordstein, Magnus
    Flisberg, Anders
    Kjellmer, Ingemar
    Lindecrantz, Kaj
    Högskolan i Borås, Institutionen Ingenjörshögskolan.
    Comparing a Supervised and an Unsupervised Classification Method for Burst Detection in Neonatal EEG2008Ingår i: Proceedings of Engineering in Medicine and Biology Society, EMBS 2008. 30th Annual International Conference of the IEEE, 20-24 August, 2008, IEEE , 2008, s. 3836-3839Konferensbidrag (Refereegranskat)
    Abstract [en]

    Hidden Markov Models (HMM) and Support Vector Machines (SVM) using unsupervised and supervised training, respectively, were compared with respect to their ability to correctly classify burst and suppression in neonatal EEG. Each classifier was fed five feature signals extracted from EEG signals from six full term infants who had suffered from perinatal asphyxia. Visual inspection of the EEG by an experienced electroencephalographer was used as the gold standard when training the SVM, and for evaluating the performance of both methods. The results are presented as receiver operating characteristic (ROC) curves and quantified by the area under the curve (AUC). Our study show that the SVM and the HMM exhibit similar performance, despite their fundamental differences.

  • 43.
    Löfhede, Johan
    et al.
    Högskolan i Borås, Institutionen Ingenjörshögskolan.
    Löfgren, N
    Thordstein, M
    Flisberg, A
    Kjellmer, I
    Lindecrantz, Kaj
    Högskolan i Borås, Institutionen Ingenjörshögskolan.
    Detection of bursts in the EEG of post asphyctic newborns2006Konferensbidrag (Refereegranskat)
  • 44.
    Löfhede, Johan
    et al.
    Högskolan i Borås, Institutionen Ingenjörshögskolan.
    Löfgren, Nils
    Thordstein, Magnus
    Flisberg, Anders
    Kjellmer, Ingemar
    Lindecrantz, Kaj
    Högskolan i Borås, Institutionen Ingenjörshögskolan.
    Classification of burst and suppression in the neonatal electroencephalogram2008Ingår i: Journal of Neural Engineering, ISSN 1741-2560, E-ISSN 1741-2552, Vol. 5, nr 4, s. 402-410Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Fisher's linear discriminant (FLD), a feed-forward artificial neural network (ANN) and a support vector machine (SVM) were compared with respect to their ability to distinguish bursts from suppressions in electroencephalograms (EEG) displaying a burst-suppression pattern. Five features extracted from the EEG were used as inputs. The study was based on EEG signals from six full-term infants who had suffered from perinatal asphyxia, and the methods have been trained with reference data classified by an experienced electroencephalographer. The results are summarized as the area under the curve (AUC), derived from receiver operating characteristic (ROC) curves for the three methods. Based on this, the SVM performs slightly better than the others. Testing the three methods with combinations of increasing numbers of the five features shows that the SVM handles the increasing amount of information better than the other methods.

  • 45.
    Löfhede, Johan
    et al.
    Högskolan i Borås, Institutionen Ingenjörshögskolan.
    Löfgren, Nils
    Thordstein, Magnus
    Flisberg, Anders
    Kjellmer, Ingmar
    Lindecrantz, Kaj
    Högskolan i Borås, Institutionen Ingenjörshögskolan.
    Classification of Burst Suppression and Tracé Alternant in Neonatal EEG2008Ingår i: Proceedings of Medicinteknikdagarna 2008. Annual conference of Svensk Förening för Medicinsk Teknik och Fysik, Göteborg, Oct., 2008, 2008Konferensbidrag (Refereegranskat)
  • 46. Macias, Raul
    et al.
    Seoane, Fernando
    Högskolan i Borås, Institutionen Ingenjörshögskolan.
    Bragos, Ramon
    Performance of the Load-in-the-Loop Single Op-Amp Voltage Controlled Current Source from the Op-Amp Parameters2010Ingår i: Journal of Physics: Conference Series, Institute of Physics Publishing Ltd. , 2010Konferensbidrag (Refereegranskat)
    Abstract [en]

    In recent years, Electrical Bioimpedance (EBI) methods have gained importance. These methods are often based on obtaining impedance spectrum in the range of β-dispersion, i.e. from a few kHz up to some MHz. To measure EBI a constant current is often injected and the voltage across the tissue under study (TUS) is recorded. Due to the performance of the current source influences the performance of the entire system, in terms of frequency range, several designs have been implemented and studied. In this paper the basic structure of a Voltage-Controlled Current Source (VCCS) based on a single Op-Amp in inverter configuration with a floating load, known as load-in-the-loop current source, is revisited and studied deeply. We focus on the dependence of the output impedance with the circuit parameters, i.e. the feedback resistor and the inverter-input resistor, and the Op-Amp main parameters, i.e. open loop gain, CMRR and input impedance. After obtaining the experimental results and comparing to the theoretical and simulated ones, they confirm the design under study can be a good solution for multi-frequency wideband EBI applications because of higher values of the output impedance than 100kΩ at 1MHz are obtained. Furthermore, an enhancement of the basic design, using a current conveyor as a first stage, is proposed, studied and implemented.

  • 47.
    Magnusson, Andreas
    Högskolan i Borås, Institutionen Ingenjörshögskolan.
    Evolutionary optimisation of a morphological image processor for embedded systems2008Doktorsavhandling, monografi (Övrigt vetenskapligt)
    Abstract [en]

    The work presented in this thesis concerns the design, development and implementation of two digital components to be used, primarily, in autonomously operating embedded systems, such as mobile robots. The first component is an image coprocessor, for high-speed morphological image processing, and the second is a hardware-based genetic algorithm coprocessor, which provides evolutionary computation functionality for embedded applications. The morphological image coprocessor, the Clutter-II, has been optimised for efficiency of implementation, processing speed and system integration. The architecture employs a compact hardware structure for its implementation of the morphological neighbourhood transformations. The compact structure realises a significantly reduced hardware resource cost. The resources saved by the compact structure can be used to increase parallelism in image processing operations, thereby improving processing speed in a similarly significant manner. The design of the Clutter-II as a coprocessor enables easy-to-use and efficient access to its image processing capabilities from the host system processor and application software. High-speed input-output interfaces, with separated instruction and data buses, provide effective communication with system components external to the Clutter-II. A substantial part of the work presented in this thesis concerns the practical implementation of morphological filters for the Clutter-II, using the compact transformation structure. To derive efficient filter implementations, a genetic algorithm has been developed. The algorithm optimises the filter implementation by minimising the number of operations required for a particular filter. The experience gained from the work on the genetic algorithm inspired the development of the second component, the HERPUC. HERPUC is a hardware-based genetic algorithm processor, which employs a novel hardware implementation of the selection mechanism of the algorithm. This, in combination with a flexible form of recombination operator, has made the HERPUC an efficient hardware implementation of a genetic algorithm. Results indicate that the HERPUC is able to solve the set of test problems, to which it has been applied, using fewer fitness evaluations and a smaller population size, than previous hardware-based genetic algorithm implementations.

  • 48.
    Malmgren, Kristina
    et al.
    University of Gothenburg.
    Sandsjö, Leif
    Högskolan i Borås, Akademin för vård, arbetsliv och välfärd.
    "wearIT" - Smart textiles project2017Ingår i: Engineering Health - The Legacy of William Chalmers, 2017Konferensbidrag (Övrigt vetenskapligt)
  • 49.
    Maronidis, A.
    et al.
    CERTH, Thessaloniki, Greece.
    Chatzilari, E.
    CERTH, Thessaloniki, Greece.
    Kontopoulos, E.
    CERTH, Thessaloniki, Greece.
    Nikopoulos, S.
    CERTH, Thessaloniki, Greece.
    Riga, M.
    CERTH, Thessaloniki, Greece.
    Mitzias, P.
    CERTH, Thessaloniki, Greece.
    Darányi, Sándor
    Högskolan i Borås, Akademin för bibliotek, information, pedagogik och IT.
    Wittek, Peter
    Högskolan i Borås, Akademin för bibliotek, information, pedagogik och IT.
    Gill, A.
    King's College London, UK.
    Tonkin, E.L.
    King's College London, UK.
    De Weerdt, D.
    SpaceApps, Belgium.
    Corubolo, F.
    University of Liverpool, UK.
    Waddington, S.
    King's College London, UK.
    Sauter, Ch.
    King's College London, UK.
    PERICLES Deliverable 4.3: Content Semantics and Use Context Analysis Techniques2016Rapport (Refereegranskat)
    Abstract [en]

    The current deliverable summarises the work conducted within task T4.3 of WP4, focusing on the extraction and the subsequent analysis of semantic information from digital content, which is imperative for its preservability. More specifically, the deliverable defines content semantic information from a visual and textual perspective, explains how this information can be exploited in long-term digital preservation and proposes novel approaches for extracting this information in a scalable manner. Additionally, the deliverable discusses novel techniques for retrieving and analysing the context of use of digital objects. Although this topic has not been extensively studied by existing literature, we believe use context is vital in augmenting the semantic information and maintaining the usability and preservability of the digital objects, as well as their ability to be accurately interpreted as initially intended.

  • 50.
    Marquez, Juan Carlos
    Högskolan i Borås, Institutionen Ingenjörshögskolan.
    On the Feasibility of Using Textile Electrodes for Electrical Bioimpedance Measurements2011Licentiatavhandling, monografi (Övrigt vetenskapligt)
    Abstract [en]

    The application of textile electrodes has been widely studied for biopotential recordings, especially for monitoring cardiac activity. Commercially available applications, such as the Adistar T-shirt and the Numetrex Cardioshirt, have shown good performance for heart rate monitoring and are available worldwide. Textile technology can also be used for electrical bioimpedance (EBI) spectroscopy measurements in home and personalized health monitoring applications, however solid basic research about the measurement performance of the electrodes must be performed prior to the development of any textile-enabled EBI application. This research work studies the performance of EBI spectroscopy measurements when performed with textile electrodes. An analysis using an electrical circuit equivalent model and experimental data obtained with the Impedimed spectrometer SFB7 was carried out. The experimental study focused on EBI spectroscopy measurements obtained with different types of textile electrodes and in different measurement scenarios. The equivalent model analysis focused on the influence of the electrode polarization impedance Zep on the EBI spectroscopy measurements in the frequency range of 3 kHz to 500 kHz. The analysis of the obtained complex EBI spectra shows that the measurements obtained with textile electrodes produce constant and reliable EBI spectra. The results also indicate the importance of the skin-electrode interface in EBI spectroscopy measurement. Textile technology, if successfully integrated, may enable the performance of EBI spectroscopy measurements in new scenarios, which would allow the generation of novel, wearable, or textile-enabled applications for home and personal health monitoring

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