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  • 401. Ughi, G. J.
    et al.
    Adriaenssens, T.
    Larsson, Matilda
    KTH, School of Technology and Health (STH), Medical Engineering. Katholieke Universiteit Leuven, Belgium.
    Dubois, C.
    Sinnaeve, P.
    Coosemans, M.
    Desmet, W.
    D'Hooghe, J.
    Automatic three-dimensional registration of intra-vascular optical coherence tomography images for the clinical evaluation of stent implantation over time2012In: Progress in Biomedical Optics and Imaging - Proceedings of SPIE, SPIE - International Society for Optical Engineering, 2012, Vol. 8213, p. 82132K-Conference paper (Refereed)
  • 402. Ughi, Giovanni
    et al.
    Adriaenssens, T.
    Larsson, Matilda
    KTH, School of Technology and Health (STH), Medical Engineering.
    Dubois, C.
    Sinnaeve, P.
    Coosemans, M.
    Desmet, W.
    D'hooge, Jan
    Automated three-dimensional registration of intra-vascular optical coherence tomography images for the clinical evaluation of stent implantation over time2012Conference paper (Refereed)
  • 403. Vaidya, A. S.
    et al.
    Radhika, T. S. L.
    Srinivas, M. B.
    Mridha, Mannan
    KTH, School of Technology and Health (STH), Health Systems Engineering, Systems Safety and Management.
    Estimation of arterial stiffness through pulse transit time measurement2014In: BIODEVICES 2014 - 7th Int. Conference on Biomedical Electronics and Devices, Proceedings; Part of 7th International Joint Conference on Biomedical Engineering Systems and Technologies, BIOSTEC 2014, 2014, p. 238-242Conference paper (Refereed)
    Abstract [en]

    Early detection of cardiovascular disease (CVD) and its treatment is significantly expected to reduce the mortality rate across the world. While several diagnostic techniques have been developed for early detection of the CVD, recent focus has been on measuring the 'arterial stiffness', which appears to be a major indicator of onset of cardio vascular disease. In this work, authors consider three mathematical models that relate pulse wave velocity (PWV) with arterial stiffness. While one model considers blood to be a nonviscous and incompressible fluid, the other considers it to be a viscous and compressible. Pulse transit time has been measured experimentally for five different individuals of different ages and heights from where PWV has been estimated. Using values of PWV, Young's modulus of elasticity has been derived. Data related to arteries such as radius, wall thickness, density and viscosity of blood have been taken from published literature where these parameters have been measured using techniques such as MRI. Initial results indicate that different models predict different estimates for arterial stiffness that depend on assumptions made.

  • 404.
    Valastyán, Iván
    et al.
    KTH, School of Technology and Health (STH), Medical Engineering.
    Brodin, Lars-Åke
    KTH, School of Technology and Health (STH), Medical Engineering.
    Elmqvist, Håkan
    KTH, School of Technology and Health (STH), Medical Engineering.
    Kerek, Andras
    KTH, School of Technology and Health (STH), Medical Engineering.
    Molnar, J.
    Novak, D.
    Ribbe, T.
    Gated tomographic imaging in ectomography using a dynamic heart phantom2007In: Nuclear Science Symposium Conference Record, 2007. NSS '07. IEEE, IEEE , 2007, p. 3414-3417Conference paper (Refereed)
    Abstract [en]

    A new computer controlled dynamic heart phantom and the connection of an ECG unit to a tomographic gamma camera system, developed for ectomographic imaging, is presented. The phantom is used for validation of the camera. Measurements were performed to test the phantom as well as to study the feasibility of gated imaging in ectomography. The camera is intended for early diagnosis of myocardial and cerebral infarctions.

  • 405.
    Valastyán, Iván
    et al.
    KTH, School of Technology and Health (STH), Medical Engineering.
    Colarieti-Tostia, Massimiliano
    KTH, School of Technology and Health (STH), Medical Engineering.
    Rena, W.
    Turcoa, A.
    Kereka, A.
    Monte Carlo simulation of a dental Positron Emission Tomograph and image reconstruction of scatter and true coincidence events2012In: 2012 IEEE Nuclear Science Symposium and Medical Imaging Conference Record (NSS/MIC), IEEE , 2012, p. 3484-3487Conference paper (Refereed)
    Abstract [en]

    Detection of inflammation with nuclear medical imaging techniques [1], especially using PET, has an important role because the location of the disease helps the doctor in the choice of the treatment. In dental applications, the proper treatment of the inflammation might save a tooth.

  • 406.
    Valastyán, Iván
    et al.
    KTH, School of Technology and Health (STH), Medical Engineering.
    Gal, J.
    Hegyesi, G.
    Kalinka, G.
    Nagy, F.
    Kiraly, B.
    Imrek, J.
    Molnar, J.
    Colarieti-Tosti, Massimiliano
    KTH, School of Technology and Health (STH), Medical Engineering.
    Szabo, Z.
    Balkay, L.
    Novel time over threshold based readout method for MRI compatible small animal PET detector2012In: 2012 IEEE Nuclear Science Symposium and Medical Imaging Conference (NSS/MIC), IEEE , 2012, p. 1295-1299Conference paper (Refereed)
    Abstract [en]

    Combined PET-MRI scanners start a new era in medical imaging. However the development of MRI compatible PET detector module is a challenging task. SiPM sensors are insensitive to magnetic field and constitute a promising solution. A drawback is the high dark current. A readout concept for SiPM based small animal PET detector module is presented in this paper. The results show that the readout of the SiPM is possible using only four ADC channels and the position map is comparable to the ideal solution. The detector modules based on the method are feasible solution for MRI compatible PET scanners.

  • 407. Van den Hoogen, J.
    et al.
    Meijer, Sebastiaan
    KTH, School of Technology and Health (STH), Health Systems Engineering, Health Care Logistics.
    Gaming Simulation Hybrids in the Railway Domain: How Games Impact the Volatility of Innovation Processes2016In: SIMULATION AND GAMING IN THE NETWORK SOCIETY / [ed] Kaneda, T Kanegae, H Toyoda, Y Rizzi, P, SPRINGER-VERLAG SINGAPORE PTE LTD , 2016, p. 291-307Conference paper (Refereed)
    Abstract [en]

    Innovation processes in the railway domain are highly chaotic due to the reciprocal influences of technological, social, and institutional dynamics over time. The ways by which gaming simulation can contribute to these processes is therefore highly context, time, and history dependent. Using three case studies, we explore basic recurrent patterns in these innovation processes and how the employment of gaming simulation has alleviated or attenuated these patterns. For different product architectures that characterize the innovation artifact, different patterns arise in different sequences for the process. We conclude that gaming's main active substance is in the opening up or closing down of technological, social, and institutional spaces. In addition, this impact is again highly moderated by the specific constellation of these spaces when a game is designed, executed, and analyzed. Broadly we see that in stable times, gaming simulation is able to decrease stability and thereby front-load much of the volatility otherwise found at later stages of the innovation process. In contrast, gaming simulation's ability to decrease volatility in volatile times is more problematic.

  • 408. Van Den Hoogen, J.
    et al.
    Meijer, Sebastiaan
    KTH, School of Technology and Health (STH).
    Lessons on the design of gaming simulations for convergence and divergence in volatile innovation environments2016In: Proceedings - Winter Simulation Conference, IEEE conference proceedings, 2016, p. 1044-1055Conference paper (Refereed)
    Abstract [en]

    Gaming simulation allows innovation stakeholders to experiment with innovations in a shielded environment. The main contribution to innovation processes is not solely the provision of knowledge to stakeholders but also the manipulation of process volatility. Volatility is the speed and magnitude by which innovations, stakeholders and institutions change during the process, creating unpredictability and uncontrollability. This paper posits that a more even distribution of volatility over time is beneficial and that gaming simulation is able to contribute to this. The use of games allows innovation managers to front-load volatility beforehand or diminish it when it occurs. Crucial is that both effects demand from games qualitatively different design choices. This paper distills, from a multitude of gaming experiments in the U.K. And Dutch railroad sector, a set of design choices to consider. This enables game designers and innovation managers to improve the impact of gaming simulation on innovation processes.

  • 409.
    van Dommelen, JAW
    et al.
    Eindhoven University of Technology, Department of Mechanical Engineering.
    Cloots, Rudy J.H.
    Eindhoven University of Technology, Department of Mechanical Engineering.
    Hrapko, Matej
    Eindhoven University of Technology, Department of Mechanical Engineering.
    Peters, G.W.M
    Eindhoven University of Technology, Department of Mechanical Engineering.
    Kleiven, Svein
    KTH, School of Technology and Health (STH), Neuronic Engineering.
    Nyberg, Tobias
    KTH, School of Technology and Health (STH), Neuronic Engineering.
    Geers, Marc
    Eindhoven University of Technology, Department of Mechanical Engineering.
    Mechanics of Traumatic Brain Injury at Multiple Length Scales2010In: Proceedings of the 16th US National Congress on Theoretical and Applied Mechanics, State College, 2010Conference paper (Refereed)
    Abstract [en]

    Current numerical head models predict the response of the brain based on a geometrically homogeneous anatomical structure. However, these models often lack the detailed anatomy of the heterogeneous structures within the head and an accurate description of the constitutive response of the brain tissue. A nonlinear constitutive model for brain tissue has been developed and validated. The consequences of meso-level heterogeneities in the brain for the development of traumatic brain injury have been investigated, as well as the orientationdependent sensitivity of brain tissue to mechanical loads based on a cellular injury mechanism.

  • 410.
    Vega-Barbas, Mario
    et al.
    KTH, School of Technology and Health (STH), Medical Engineering, Medical sensors, signals and systems.
    Pau, Ivan
    Univerisdad Politecnica de Madrid.
    Seoane, Fernando
    KTH, School of Technology and Health (STH), Medical Engineering, Medical sensors, signals and systems.
    Confidence: dependencies and their critical role in fostering user acceptance in pervasive applications2014Conference paper (Refereed)
    Abstract [en]

    Pervasive computing offers new scenarios where users are surrounded by invisible and proactive technology making smart spaces. Although the utility and power of solutions developed using this computer paradigm are proved, there are unresolved problems that hinder their acceptance and inclusion in our private life. Users have problems understanding the operations of a pervasive computing solution, and therefore they should trust that the solution works properly and according to their expectations. Nevertheless, the concept of trust is already framed in a specific use within the ecosystem of applications that can populate a smart space. To take this concept of trust to the whole space, we propose to study and define the concept of confidence. In contrast to the concept of trust, confidence has deeper psychological implications.

  • 411. Verrecchia, L
    et al.
    Brantberg, K
    Tribukait, Arne
    KTH, School of Technology and Health (STH), Environmental Physiology.
    Gennser, Mikael
    KTH, School of Technology and Health (STH), Environmental Physiology.
    Partial labyrinthine injury in severe decompression illness: a vascular embolic explanation?2010Conference paper (Refereed)
  • 412. Verrecchia, L
    et al.
    Tribukait, Arne
    KTH, School of Technology and Health (STH), Environmental Physiology.
    Gennser, Mikael
    KTH, School of Technology and Health (STH), Environmental Physiology.
    Brantberg, K
    Perifer övre segmental vestibulär pares vid svår dekompressionssjuka: finns vaskulär embolisk orsak?2010Conference paper (Refereed)
  • 413.
    Vogel, Kjerstin
    et al.
    KTH, School of Technology and Health (STH), Health Systems Engineering, Ergonomics.
    Karltun, Johan
    School of Engineering, Jönköping University.
    Eklund, Jörgen
    KTH, School of Technology and Health (STH), Ergonomics (Closed 20130701).
    Ergonomic changes and their consequences in a Swedish meat cutting plant2010In: 44th Annual Nordic Ergonomics Society Conference: Proactive Ergonomics - implementation of ergonomics in planning of jobs, tasks, systems and environments, 2010Conference paper (Refereed)
    Abstract [en]

    Rotation schemes reducing daily working time with knife to 6 hours were planned and implemented at a meat cutting plant in a participatory process. These changes were evaluated concerning results, the change process and consequences on organizational performance. A questionnaire to the meat cutters and interviews with the production leaders were conducted. The results support that the meat cutters experienced the changes positively and that a reduction in physical and mental fatigue was reached. Other experiences were mixed indicating that both work organizational characteristics and local history should be taken more into consideration. The organizational performance was not particularly affected.

  • 414.
    Vogel, Kjerstin
    et al.
    KTH, School of Technology and Health (STH), Ergonomics (Closed 20130701).
    Karltun, Johan
    KTH, School of Technology and Health (STH), Health Systems Engineering, Ergonomics. Jönköpings Tekniska Högskola.
    Åström, Peter
    KTH, School of Technology and Health (STH), Health Systems Engineering, Ergonomics.
    Stay sharp2014In: Human Factors in Organizational design and Management: Xi Nordiv Ergonomics Society Annual Conference, Copenhagen 2014 / [ed] O. Broberg, N. Fallentin, P. Hasle, P.L. Jensen, A. Kabel, M.E. Larsen, T. Weller, 2014, p. 429-434Conference paper (Refereed)
    Abstract [en]

    Meat cutters’ work is physically demanding and is performed mainly with thehand held tool of a knife. The aim of this paper is to report experiences of how researcherstogether with three companies of different size and character developed and carried out aneducation program in maintaining knife sharpness for meat cutters. It describes the processof developing an educational program suited for the business and discusses the outcome.

  • 415.
    Vänje, Annika
    et al.
    KTH, School of Technology and Health (STH), Health Systems Engineering.
    Nord Nilsson, Lena
    KTH, School of Technology and Health (STH), Health Systems Engineering.
    WIKIOSH: to develop learning networks about safety and health in the engineering sector2015In: Proceedings 19th Triennial Congress of the IEA, Melbourne 9-14 August 2015, International Ergonomics Association , 2015, p. 1411-Conference paper (Refereed)
    Abstract [en]

    In this paper a network for knowledge sharing is presented. The network turns to safety and health engineers, ergonomists and researchers working in or with the manufacturing industry. The aim with the network is to strengthen and share sector related knowledge on safety and health. The results show a high interest in this kind of network and that the need for knowledge on how to handle complex situations is in focus, and not how to solve specific one dimensional problems.

  • 416.
    Waldenström, Anders
    et al.
    Umeå universitet.
    Erlandsson, Björn-Erik
    KTH, School of Technology and Health (STH), Health Systems Engineering, Systems Safety and Management.
    Incidenter i vården: Hur tar vi tillvara erfarenheterna för en säkrare vård?2014Conference paper (Refereed)
    Abstract [sv]

    Sjukvården blir alltmer komplicerad. Möjligheterna ökar med även riskerna. Mångåriga neddragningar i delar av vården kan inte ske utan risk att påverka säkerheten. Samhället har ett ansvar att minimera dessa risker. Med erfarenhet av ett fall utrett av Statens Haverikommission vill vi ventilera dessa frågor för att skapa debatt om hur detta arbete bäst kan bedrivas.

  • 417.
    Wang, Chunliang
    KTH, School of Technology and Health (STH), Medical Engineering, Medical Image Processing and Visualization.
    Segmentation of multiple structures in chest radiographs using multi-task fully convolutional networks2017In: 20th Scandinavian Conference on Image Analysis, SCIA 2017, Springer, 2017, Vol. 10270, p. 282-289Conference paper (Refereed)
    Abstract [en]

    Segmentation of various structures from the chest radiograph is often performed as an initial step in computer-aided diagnosis/detection (CAD) systems. In this study, we implemented a multi-task fully convolutional network (FCN) to simultaneously segment multiple anatomical structures, namely the lung fields, the heart, and the clavicles, in standard posterior-anterior chest radiographs. This is done by adding multiple fully connected output nodes on top of a single FCN and using different objective functions for different structures, rather than training multiple FCNs or using a single FCN with a combined objective function for multiple classes. In our preliminary experiments, we found that the proposed multi-task FCN can not only reduce the training and running time compared to treating the multi-structure segmentation problems separately, but also help the deep neural network to converge faster and deliver better segmentation results on some challenging structures, like the clavicle. The proposed method was tested on a public database of 247 posterior–anterior chest radiograph and achieved comparable or higher accuracy on most of the structures when compared with the state-of-the-art segmentation methods.

  • 418.
    Wang, Chunliang
    et al.
    KTH, School of Technology and Health (STH).
    Smedby, Örjan
    KTH, School of Technology and Health (STH).
    Automatic whole heart segmentation using deep learning and shape context2018In: 8th International Workshop on Statistical Atlases and Computational Models of the Heart, STACOM 2017, Held in Conjunction with MICCAI 2017, Springer, 2018, Vol. 10663, p. 242-249Conference paper (Refereed)
    Abstract [en]

    To assist 3D cardiac image analysis, we propose an automatic whole heart segmentation using a deep learning framework combined with shape context information that is encoded in volumetric shape models. The proposed processing pipeline consists of three major steps: scout segmentation with orthogonal 2D U-nets, shape context estimation and refining segmentation with U-net and shape context. The proposed method was evaluated using the MMWHS challenge data. Two sets of networks were trained separately for contrast-enhanced CT and MRI. On the 20 training datasets, using 5-fold cross-validation, the average Dice coefficients for the left ventricle, the right ventricle, the left atrium, the right atrium and the myocardium of the left ventricle were 0.895, 0.795, 0.847, 0.821, 0.807 for MRI and 0.935, 0.825, 0.908, 0.881, 0.879 for CT, respectively. Further improvement may be possible given more training data or advanced data augmentation strategy.

  • 419.
    Wang, Chunliang
    et al.
    KTH, School of Technology and Health (STH).
    Wang, Q.
    Smedby, Örjan
    KTH, School of Technology and Health (STH), Medical Engineering, Medical Image Processing and Visualization.
    Automatic heart and vessel segmentation using random forests and a local phase guided level set method2017In: Reconstruction, Segmentation, and Analysis Of Medical Images, Springer Verlag , 2017, Vol. 10129, p. 159-164Conference paper (Refereed)
    Abstract [en]

    In this report, a novel automatic heart and vessel segmentation method is proposed. The heart segmentation pipeline consists of three major steps: heart localization using landmark detection, heart isolation using statistical shape model and myocardium segmentation using learning based voxel classification and local phase analysis. In our preliminary test, the proposed method achieved encouraging results.

  • 420.
    Wibe, Torunn
    et al.
    Oslo Universitet.
    Ekstedt, Mirjam
    KTH, School of Technology and Health (STH).
    Hellesö, Ragnhild
    Oslo Universitet.
    Varsi, Cecilie
    Oslo Universitet Hospital.
    Ruland, Cornelia
    Oslo University Hospital.
    “You Are Not at All Bothersome”: Nurses’ Online Communication withTesticular Cancer Patients2012Conference paper (Refereed)
    Abstract [en]

    To some extent, electronic communication has supplemented nurses’ face-to-face contact with patients over the last few years. In this paper, we report findings from a study in which we examined cancer nurses’ answers to messages from testicular cancer patients in a nurse-managed online patient-provider communication service. The aim of the study was to investigate how nurses manage to meet patients’ different questions and concerns, and what aspects of expert nursing care are demonstrated when they communicate with patients online. The content of the messages formed a continuum from practical to existential issues. In their answers, the nurses demonstrated an ability to make reflected choices between both support modalities and means of communication. The professional knowledge and care of expert cancer nurses were clearly exposed in the nurses’ answers, although they were good at adapting their professional language so that it would be understandable to the patients.

  • 421. Wibeab, T.
    et al.
    Ekstedt, Mirjam
    KTH, School of Technology and Health (STH), Health Systems Engineering, Systems Safety and Management.
    Hellesø, R.
    Øyrid, K.
    Slaughter, L.
    Clinical documentation as a source of information for patients- possibilities and limitations2013In: Studies in Health Technology and Informatics, IOS Press, 2013, no 1-2, p. 793-797Conference paper (Refereed)
    Abstract [en]

    Recent legislation in many countries has given patients the right to access their own patient records. Making health-care professionals' assessments and decisions more transparent by giving patients access to their records is expected to provide patients with useful health information and reduce the power imbalance between patient and provider. We conducted both a mail survey and a face-to-face interview study, including patients who had requested a paper copy of their patient records (EPR), to explore their experiences. For many study participants, a view of their records filled in holes in the oral information they previously received. They had problems understanding parts of what they read, but rarely asked for help. Instead they searched for explanations on the Internet or attempted to understand based on the context. Patients are still afraid of seeming suspicious or displeased if they indicate that they would like to read their records. Health-care organizations should consider actively offering patients the chance to view their clinical documentation to a larger extent than what has been done so far.

  • 422.
    Widman, Erik
    et al.
    KTH, School of Technology and Health (STH), Medical Engineering, Medical Imaging.
    Caidahl, K.
    Larsson, Matilda
    KTH, School of Technology and Health (STH), Medical Engineering, Medical Imaging.
    In vivo radial and longitudinal carotid artery plaque strain estimation via ultrasound-based speckle tracking2014In: 2014 IEEE International Ultrasonics Symposium (IUS), IEEE Computer Society, 2014, p. 523-526Conference paper (Refereed)
    Abstract [en]

    Our objective was to assess strain in common carotid artery (CCA) plaques using a previously validated speckle tracking algorithm. Radial and longitudinal strain was measured in 7 patients (77 ± 6 years) with carotid atherosclerosis and was compared with a quantitative visual assessment grading of plaques on the Gray-Weale scale by two experienced physicians. A greater pulse-pressure adjusted radial and longitudinal strain was found in echolucent plaques compared to echogenic plaques. This study shows the feasibility of ultrasound speckle tracking strain estimation in plaques and indicates the possibility to characterize plaques using speckle tracking strain in vivo.

  • 423.
    Widman, Erik
    et al.
    KTH, School of Technology and Health (STH), Medical Engineering, Medical Imaging.
    Caidahl, Kenneth
    Karolinska Institutet.
    Heyde, Brecht
    KU Leuven.
    D’hooge, Jan
    KU Leuven.
    Larsson, Matilda
    KTH, School of Technology and Health (STH), Medical Engineering, Medical Imaging.
    Speckle tracking strain estimation of a carotid artery plaque phantom - Validation via sonomicrometry2013In: 2013 IEEE International Ultrasonics Symposium (IUS), IEEE conference proceedings, 2013, , p. 4p. 1757-1760Conference paper (Refereed)
    Abstract [en]

    Current clinical ultrasound-based methods for plaque characterization are limited to visual assessment of plaque echogenicity creating demand for quantitative diagnostic tools. Our objective was to validate radial and longitudinal speckle tracking (ST) strain in phantom plaques via sonomicrometry (sono), and to compare the peak plaque and arterial wall strain. Four carotid artery gel-phantoms with a soft wall inclusion, mimicking a vulnerable plaque, were constructed. The phantoms were connected to a programmable pump simulating a carotid flow. Cineloops were acquired using a GE Vivid E9 where radial and longitudinal strain were calculated using a normalized cross-correlation ST algorithm. The region of interest was adjusted according to the plaque size. Sonomicrometry was used as a reference measurement. The correlation between estimated mean peak strain and the reference peak strain was r = 0.96 (p < 0.001) radially and r = 0.75 (p ≤ 0.005) longitudinally. The soft plaque exhibited 35.1% (SD 16.9%) greater radial (p < 0.001) and 88.6% (SD 72.0%) greater longitudinal (p < 0.001) peak strain than the arterial wall when measured with speckle tracking. It was possible to estimate plaque strain by ST and to distinguish a soft plaque from the vessel wall via strain measurements.

  • 424.
    Widman, Erik
    et al.
    KTH, School of Technology and Health (STH), Medical Engineering, Medical Imaging. Karolinska Inst, Sweden.
    Maksuti, Elira
    KTH, School of Technology and Health (STH), Medical Engineering, Medical Imaging.
    Carrascal, Carolina Amador
    Urban, Matthew W.
    Larsson, Matilda
    KTH, School of Technology and Health (STH), Medical Engineering, Medical Imaging. Karolinska Inst, Sweden.
    Evaluating Arterial and Plaque Elasticity with Shear Wave Elastography in an ex vivo Porcine Model2015In: 2015 IEEE INTERNATIONAL ULTRASONICS SYMPOSIUM (IUS), IEEE , 2015Conference paper (Refereed)
    Abstract [en]

    Our objective was to use shear wave elastography (SWE) to characterize the mechanical properties of an arterial wall with a simulated calcified plaque in an ex vivo setup. A small porcine aorta was used as a model for a human carotid artery and attached to a fixture while pressurized with a water column. The stiffness of the arterial wall and a simulated plaque were estimated using SWE. The mean arterial wall and plaque shear modulus varied from 42 +/- 0 kPa to 100 +/- 1 kPa and 81 +/- 2 kPa to 174 +/- 2 kPa respectively over a pressure range of 20-120 mmHg. The results show the ability of SWE to characterize the mechanical properties of an arterial wall with a simulated plaque and take steps toward an in vivo implementation for quantitative plaque assessment.

  • 425.
    Widman, Erik
    et al.
    KTH, School of Technology and Health (STH), Medical Engineering, Medical Imaging.
    Maksuti, Elira
    KTH, School of Technology and Health (STH), Medical Engineering, Medical Imaging.
    Larsson, David
    KTH, School of Technology and Health (STH), Medical Engineering, Medical Imaging.
    Urban, M.
    Caidahl, K.
    KTH, School of Technology and Health (STH), Medical Engineering.
    Bjällmark, Anna
    KTH, School of Technology and Health (STH), Medical Engineering, Medical Imaging.
    Larsson, Matilda
    KTH, School of Technology and Health (STH), Medical Engineering, Medical Imaging.
    Feasibility of shear wave elastography for plaque characterization2014In: IEEE International Ultrasonics Symposium, IUS, 2014, p. 1818-1821Conference paper (Refereed)
    Abstract [en]

    Determining plaque vulnerability is critical when selecting the most suitable treatment for patients with atherosclerotic plaque in the common carotid artery and quantitative characterization methods are needed. In this study, shear wave elastography (SWE) was used to characterize soft plaque mimicking inclusions in three atherosclerotic arterial phantoms by using phase velocity analysis in a static environment. The results were validated with axial tensile mechanical testing (MT). SWE measured a mean shear modulus of 5.8 ± 0.3 kPa and 25.0 ± 1.2 kPa versus 3.0 kPa and 30.0 kPa measured by mechanical testing in the soft plaques and phantom walls respectively. The results show good agreement between MT and SWE for both the plaque and phantom wall.

  • 426.
    Widman, Erik
    et al.
    KTH, School of Technology and Health (STH), Medical Engineering, Medical Imaging.
    Maksuti, Elira
    KTH, School of Technology and Health (STH), Medical Engineering, Medical Imaging.
    Larsson, Matilda
    KTH, School of Technology and Health (STH), Medical Engineering, Medical Imaging.
    Bjällmark, Anna
    KTH, School of Technology and Health (STH), Medical Engineering, Medical Imaging.
    Caidahl, K.
    D'Hooge, J.
    Shear wave elastography for characterization of carotid artery plaques-A feasibility study in an experimental setup2012In: 2012 IEEE International Ultrasonics Symposium (IUS), IEEE , 2012, p. 6562400-Conference paper (Refereed)
    Abstract [en]

    Characterization of vulnerable plaques in the carotid artery is critical for the prevention of ischemic stroke. However, ultrasound-based methods for plaque characterization used in the clinics today are limited to visual assessment and evaluation of plaque echogenicity. Shear Wave Elastography (SWE) is a new tissue characterization technique based on radiation force-induced shear wave propagation with potential use in plaque vulnerability assessment. The purpose of this study was to develop an experimental setup to test the feasibility of SWE for carotid plaque characterization. A carotid artery phantom with a soft inclusion in the wall, mimicking a vulnerable plaque, was constructed (10% polyvinyl alcohol (PVA), 3% graphite) by exposing the vessel and plaque to three and one freeze-thaw cycles (6h freeze, 6h thaw) respectively. An Aixplorer SWE system (Supersonic Imagine) was used to measure the shear wave speed (cT) in the vessel wall and plaque. The Young's modulus (E) was then calculated via the Moens-Korteweg (M-K) equation. For comparison, eight cylinders (d = 4 cm, h = 4 cm) were constructed for mechanical testing from the same PVA batch, of which four were exposed to three freeze-thaw cycles (mimicking the vessel wall) and four to one freeze-thaw cycle (mimicking the plaque). The Young's moduli for the cylinders were obtained via a displacement controlled mechanical compression test (Instron 5567) by applying 5% strain. The mean shear wave speed was 2.6 (±0.7) m/s in the vessel wall, 1.8 (±0.7) m/s in the plaque, resulting in Evessel = 11.5 (±0.5) kPa, Eplaque = 4.3 (±0.5) kPa. The compression tests resulted in E = 64.2 (±11.1) kPa in the hard cylinder and E = 9.7 (±3.1) kPa in the soft cylinder. The results showed that it was possible to distinguish between the arterial wall and the plaque. The disagreement between mechanical testing and SWE can be explained by the fact that the shear wave does not propagate monochromatically in cylindrical geometry. To achieve a better calculation of the elastic modulus, the frequency dependency of the shear wave velocity must be considered.

  • 427. Winger, Anette
    et al.
    Ekstedt, Mirjam
    KTH, School of Technology and Health (STH), Health Systems Engineering.
    Bruun Wyller, Vegard
    Oslo University Hospital, Norway .
    Pain and quality of life among adolescents with chronic fatigue syndrome2011Conference paper (Refereed)
  • 428.
    Wåhslén, Jonas
    et al.
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    Lindh, Thomas
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    Real-time Performance Management of Assisted Living Services for Bluetooth Low Energy Sensor Communication2017In: Integrated Network and Service Management (IM), 2017 IFIP/IEEE Symposium on, IEEE conference proceedings, 2017Conference paper (Refereed)
    Abstract [en]

    PerfMon is a prototype implementation of a realtime performance management method for sensor data communication in assisted living applications. It is implemented in accordance with the specification for GATT services in Bluetooth low energy (BLE). PerfMon provides a tool for real-time performance monitoring and control for caregivers and service providers. Test results from monitoring and control of packet loss ratio related to alarm thresholds are presented. PerfMon is adapted to cloud-based web services using RESTful APIs and established object models. Performance management is a necessary component in an overall management system of IoT devices for healthcare and assisted living applications.

  • 429.
    Wåhslén, Jonas
    et al.
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    Lindh, Thomas
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering.
    Smartphone-Centric Wi-Fi Device-to-Device Sensor Communication for User Mobility in AAL Services2016In: Personal, Indoor, and Mobile Radio Communications (PIMRC), 2016 IEEE 27th Annual International Symposium on, IEEE conference proceedings, 2016, p. 80-85Conference paper (Refereed)
    Abstract [en]

    This paper evaluates a use-case for smartphone-centric Wi-Fi device-to-device sensor communication that enables user mobility in ambient assisted living (AAL) services. A real-time performance measurement method has been developed and implemented to evaluate the smartphone’s ability to act as a hub and gateway for Wi-Fi connected sensor nodes. The results show that Wi-Fi Direct and Wi-Fi Hotspot are feasible solutions for smartphone-centric device-to-device communication that enables user mobility. In addition, a cloud-based web application for monitoring and displaying sensor data has been implemented.

  • 430.
    Wåhslén, Jonas
    et al.
    KTH, School of Technology and Health (STH), Data- och elektroteknik (Closed 20130701).
    Lindh, Thomas
    KTH, School of Technology and Health (STH), Data- och elektroteknik (Closed 20130701).
    Eriksson, Martin
    KTH, School of Technology and Health (STH).
    A novel approach to multi-sensor data synchronization using mobile phones2011In: Proceedings of the 5th International ICST Conference on Body Area Networks: BodyNets 2010, 2011, p. 171-174Conference paper (Refereed)
    Abstract [en]

    This paper presents a new algorithm for synchronization of data from multiple sensors arriving to a mobile phone's Bluetooth interface with possibly unknown and different sampling frequencies. A system that provides feedback signals to an athlete is one example where it is crucial to synchronize data from several wireless sensors; especially sensor nodes use different and unknown sampling rates.

  • 431.
    Wåhslén, Jonas
    et al.
    KTH, School of Technology and Health (STH), Data- och elektroteknik (Closed 20130701).
    Orhan, Ibrahim
    KTH, School of Technology and Health (STH), Data- och elektroteknik (Closed 20130701).
    Lindh, Thomas
    KTH, School of Technology and Health (STH).
    Local Time Synchronization in Bluetooth Piconets for Data Fusion Using Mobile Phones2011In: BSN 2011: 8th International Conference on Body Sensor Networks, 2011, p. 113-138Conference paper (Refereed)
    Abstract [en]

    This paper presents a method to synchronize the clocks in a Bluetooth piconet from the application layer in a mobile phone. It adapts algorithms for time synchronization of distributed systems and the Internet to Bluetooth networks. The performance issues that cause problems for data synchronization between master and slaves in Bluetooth are highlighted. The tests show that the synchronization error is limited to one sampling time.

  • 432.
    Wåhslén, Jonas
    et al.
    KTH, School of Technology and Health (STH), Data- och elektroteknik (Closed 20130701).
    Orhan, Ibrahim
    KTH, School of Technology and Health (STH), Data- och elektroteknik (Closed 20130701).
    Sturm, Dennis
    KTH, School of Technology and Health (STH), Centres, Centre for Technology in Medicine and Health, CTMH.
    Lindh, Thomas
    KTH, School of Technology and Health (STH), Data- och elektroteknik (Closed 20130701).
    Performance evaluation of time synchronization and clock drift compensation in wireless personal area networks2012In: BodyNets '12 Proceedings of the 7th International Conference on Body Area Networks, ICST , 2012, p. 153-158Conference paper (Refereed)
    Abstract [en]

    Efficient algorithms for time synchronization, including compensation for clock drift, are essential in order to obtain reliable fusion of data samples from multiple wireless sensor nodes. This paper evaluates the performance of algorithms based on three different approaches; one that synchronizes the local clocks on the sensor nodes, and a second that uses a single clock on the receiving node (e.g. a mobile phone), and a third that uses broadcast messages. The performances of the synchronization algorithms are evaluated in wireless personal area networks, especially Bluetooth piconets and ZigBee/IEEE 802.15.4 networks. A new approach for compensation of clock drift and a realtime implementation of single node synchronization from the mobile phone are presented and tested. Finally, applications of data fusion and time synchronization are shown in two different use cases; a kayaking sports case, and monitoring of heart and respiration of prematurely born infants. 

  • 433.
    Xie, Li
    et al.
    KTH, School of Information and Communication Technology (ICT), Electronic Systems. KTH, School of Information and Communication Technology (ICT), Centres, VinnExcellence Center for Intelligence in Paper and Packaging, iPACK.
    Yang, Geng
    KTH, School of Information and Communication Technology (ICT), Electronic Systems. KTH, School of Information and Communication Technology (ICT), Centres, VinnExcellence Center for Intelligence in Paper and Packaging, iPACK.
    Xu, Linlin
    KTH, School of Information and Communication Technology (ICT), Centres, VinnExcellence Center for Intelligence in Paper and Packaging, iPACK.
    Seoane, Fernando
    KTH, School of Technology and Health (STH), Medical Engineering, Medical sensors, signals and systems.
    Chen, Qiang
    KTH, School of Information and Communication Technology (ICT), Electronic Systems. KTH, School of Information and Communication Technology (ICT), Centres, VinnExcellence Center for Intelligence in Paper and Packaging, iPACK.
    Zheng, Lirong
    KTH, School of Information and Communication Technology (ICT), Electronic Systems. KTH, School of Information and Communication Technology (ICT), Centres, VinnExcellence Center for Intelligence in Paper and Packaging, iPACK. State Key Laboratory of ASICs and Systems, Fudan University, 200433, Shanghai, China .
    Characterization of dry biopotential electrodes2013In: Proceedings of the Annual International Conference of the IEEE Engineering in Medicine and Biology Society, EMBS, 2013, p. 1478-1481Conference paper (Refereed)
    Abstract [en]

    Driven by the increased interest in wearable long-term healthcare monitoring systems, varieties of dry electrodes are proposed based on different materials with different patterns and structures. Most of the studies reported in the literature focus on proposing new electrodes and comparing its performance with commercial electrodes. Few papers are about detailed comparison among different dry electrodes. In this paper, printed metal-plate electrodes, textile based electrodes, and spiked electrodes are for the first time evaluated and compared under the same experimental setup. The contact impedance and noise characterization are measured. The in-vivo electrocardiogram (ECG) measurement is applied to evaluate the overall performance of different electrodes. Textile electrodes and printed electrodes gain comparable high-quality ECG signals. The ECG signal obtained by spiked electrodes is noisier. However, a clear ECG envelope can be observed and the signal quality can be easily improved by backend signal processing. The features of each type of electrodes are analyzed and the suitable application scenario is addressed.

  • 434.
    Yang, Liyun
    et al.
    KTH, School of Technology and Health (STH).
    Lu, Ke
    Abtahi, Farhad
    Lindecrantz, Kaj
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Ergonomics.
    Seoane, Fernando
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Ergonomics.
    Forsman, Mikael
    Institute of Environmental Medicine, Karolinska Institutet.
    Eklund, Jörgen
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Ergonomics.
    A pilot study of using smart clothes for physicalworkload assessment2017In: JOY AT WORK, Lund, Sweden, 2017, p. 169-170Conference paper (Refereed)
  • 435.
    Yu, Sicong
    et al.
    KTH, School of Technology and Health (STH).
    Hamid Muhammad, Hamed
    KTH, School of Technology and Health (STH), Health Systems Engineering, Systems Safety and Management.
    Denoising of SPECT-image sinogram-data before reconstruction2014In: WMSCI 2014 - 18th World Multi-Conference on Systemics, Cybernetics and Informatics, Proceedings, 2014, Vol. 1, p. 202-206Conference paper (Refereed)
    Abstract [en]

    Nuclear medicine images have low signal-to-noise ratio (SNR) due to several physical limitations which degrade the image quality considerably. In this study, the Gaussian filter and the patch confidence Gaussian filter (PCG) were used to improve the image quality for Single Photon Emission Computed Tomography (SPECT). The new approach applies these filtering methods on the acquired 2D-projections before reconstructing the image. The new approach was evaluated on a SPECT dataset and the performance was compared with several conventional methods presented in the literature.

  • 436.
    Yu, Sicong
    et al.
    KTH, School of Technology and Health (STH), Health Systems Engineering.
    Hamid Muhammed, Hamed
    KTH, School of Technology and Health (STH), Health Systems Engineering.
    Comparison of Pre- and Post-Reconstruction Denoising Approaches in Positron Emission Tomography2016In: THE 1ST 2016 INTERNATIONAL CONFERENCE ON BIOMEDICAL ENGINEERING (IBIOMED 2016), IEEE, 2016, p. 63-68Conference paper (Refereed)
    Abstract [en]

    In Positron Emission Tomography (PET), image quality is highly degraded by noise. Therefore, two main PETimage denoising approaches can be used: pre- and postreconstruction denoising. In the pre-reconstruction approach the PET sinogram is denoised before forwarding it to the image reconstruction algorithm. On the other hand, the reconstructed PET-image is denoised in the post-reconstruction approach. In this study, comparison of image quality of the resulting images of the pre- and post-reconstruction approaches is performed. In both types of approaches, the Gaussian filter, the Non-Local Means filter (NLM), the Block-Matching and 3D filter (BM3D), the K-Nearest Neighbors Filter (KNN) and the Patch Confidence K-Nearest Neighbors Filter (PCkNN) are utilized. These approaches are evaluated on a simulated PET-phantom dataset, a real-life physical thorax-phantom PET dataset as well as a reallife MicroPET-scan dataset of a mouse. The performance is measured using the Signal-to-Noise Ratio (SNR) in addition to the Contrast-to-Noise Ratio (CNR) in the resulting images.

  • 437.
    Yu, Sicong
    et al.
    KTH, School of Technology and Health (STH), Health Systems Engineering, Systems Safety and Management.
    Hamid Muhammed, Hamed
    KTH, School of Technology and Health (STH), Health Systems Engineering.
    Noise Type Evaluation in Positron Emission Tomography Images2016In: THE 1ST 2016 INTERNATIONAL CONFERENCE ON BIOMEDICAL ENGINEERING (IBIOMED 2016), IEEE, 2016, p. 101-106Conference paper (Refereed)
    Abstract [en]

    In Positron Emission Tomography (PET), the coincident emission of gamma photon pairs constitutes the useful signals that should be detected and processed to reconstruct the desired PET images of the studied objects. However, along with the useful signal, noise is also generated and added to the detected signals that are sorted with respect to their line-ofresponse and arranged as a sinogram for each two-dimensional slice. In this paper, the type and properties of noise in PET sinogram data will be evaluated. Furthermore, the effect of the used linear and non-linear image denoising and reconstruction procedures on the type of noise will be analyzed. For this purpose, the Gaussian filter, the Median filter, the Patch Confidence k-Nearest Neighbor filter (PCkNN) and the Block Matching 3D filter (BM3D) were used to denoise PET image data, as well as the maximum likelihood expectation maximization algorithm (MLEM) and the Filtered Back Projection algorithm (FBP) to reconstruct the PET images.

  • 438.
    Yu, Sicong
    et al.
    KTH, School of Technology and Health (STH), Health Systems Engineering, Systems Safety and Management.
    Hamid Muhammed, Hamed
    KTH, School of Technology and Health (STH), Health Systems Engineering, Systems Safety and Management.
    PET image improvement using the Patch Confidence K-Nearest Neighbors Filter2014Conference paper (Refereed)
    Abstract [en]

    In Positron Emission Tomography (PET), the resulted images are highly deteriorated by noise. In this study, we propose a new denoising framework using the Patch Confidence K-Nearest Neighbors Filter (PCKNN) to reduce noise in the sinogram before forwarding it to the reconstruction procedure. This method has been evaluated on a simulated PET image of a phantom, and the performance has been compared with several conventional methods in the literature. The results have shown that the PET image quality can be substantially improved in term of increased signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR

  • 439. Zahnd, G.
    et al.
    Larsson, Matilda
    KTH, School of Technology and Health (STH), Medical Engineering.
    Gao, H.
    Serusclat, A.
    Vray, D.
    D'Hooge, J.
    A novel method to generete synthetic ultrasound data of the carotid artery based on in vivo observation as a tool to validate algorithm accuracy2012In: 2012 IEEE International Ultrasonics Symposium (IUS), 2012, p. 1674-1677Conference paper (Refereed)
    Abstract [en]

    Ultrasound imaging represents a well designed modality to estimate the motion of biological tissues in vivo, from which relevant clinical information can be assessed. However, the lack of ground truth constitutes a challenging issue when it comes to evaluate the accuracy of computerized methods. Indeed, quantification of the reliability of experimental results often involves manual or visual human operations, which may introduce subjectivity and variability. Nonetheless, numerical simulation of the imaged tissues allow a comparison with a known reference. For this purpose, we propose in this work a realistic kinematic multi-layer model of the common carotid artery. A set of 10 models was generated by randomly positioning scatterers, on which intensity, specular reflection, and bi-dimensional motion over the duration of one cardiac cycle were applied. Two computerized methods, namely a block-matching method and a segmentation method, were also applied on our model using identical parameter settings as those used for in vivo clinical data, in the objective to assess their accuracy. The tracking errors were 42 ± 40 μm and 12 ± 10 μm in the longitudinal and radial directions, respectively. The segmentation errors were 28±18 μm for the lumen diameter, and 15±10 μm for the intima-media thickness. We conclude from these results that our model can constitute a reliable method to quantify the accuracy of computerized algorithms.

  • 440.
    Zhang, Chen
    et al.
    KTH, School of Technology and Health (STH), Health Systems Engineering, Health Care Logistics.
    Hanchi, Hamza
    KTH, School of Technology and Health (STH), Health Systems Engineering, Health Care Logistics.
    Meijer, Sebastiaan
    KTH, School of Technology and Health (STH), Health Systems Engineering, Health Care Logistics.
    Evaluating the Effect of Centralized Administration on Health Care Performances Using Discrete-Event Simulation2017Conference paper (Refereed)
  • 441.
    Zhang, Chen
    et al.
    KTH, School of Technology and Health (STH), Health Systems Engineering, Health Care Logistics.
    Hanchi, Hamza
    KTH, School of Technology and Health (STH), Health Systems Engineering, Health Care Logistics.
    Meijer, Sebastiaan
    KTH, School of Technology and Health (STH), Health Systems Engineering, Health Care Logistics.
    Identifying Influential Factors of Patient Length of Stay In a Surgery Center: a Simulation Modelling Approach2017Conference paper (Refereed)
  • 442.
    Zhang, Rui
    et al.
    University of Passau.
    Freund, Martin
    University of Passau.
    Amft, Oliver
    University of Passau.
    Cheng, Jingyuan
    DFKI.
    Zhou, Bo
    DFKI.
    Lukowicz, Paul
    DFKI.
    Seoane, Fernando
    KTH, School of Technology and Health (STH). Högskolan i Borås, Akademin för vård, arbetsliv och välfärd.
    Chabrecek, Peter
    Sefar AG.
    A generic sensor fabric for multi-modal swallowing sensing in regular upper-body shirts2016In: Proceedings of the 2016 ACM International Symposium on Wearable Computers, ACM Digital Library, 2016, p. 46-47Conference paper (Refereed)
    Abstract [en]

    We investigate a generic fabric material as basis for resistive pressure and bio-impedance sensors and apply the fabric in a shirt collar for swallowing spotting. A pilot study confirmed the signal performance of both sensor types.

  • 443.
    Zheng, Miaomiao
    et al.
    KTH, School of Technology and Health (STH), Medical Engineering.
    Härmark, Johan
    KTH, School of Technology and Health (STH), Basic Science and Biomedicine, Structural Biotechnology.
    Grishenkov, Dmitry
    KTH, School of Technology and Health (STH), Medical Engineering.
    Janerot Sjöberg, Birgitta
    CLINTEC, Department of Medical Imaging and Technology, Karolinska Institute.
    Polymer-Shelled Ultrasound Contrast Agents with controlled size and polydispersity.2011In: Nanomedicine: Nanotechnology, Biology & Medicine, 2011Conference paper (Refereed)
    Abstract [en]

    Ultrasound imaging techniques can be greatly improved by the use of ultrasound contrast agents (UCAs). Gas bubbles encapsulated into biocompatible polymer shell are of particular interest of this work. Shell of the bubbles produced from Poly-Vinyl-Alcohol (PVA) offers considerable chemical versatility and stability. However, questions regarding the size and polydispersity of the microbubbles must be further investigated. The ideal UCAs should not obstruct the blood flow in pulmonary capillaries which diameter is less than 10 μm. From the technical perspective UCAs should modify the acoustic properties of a region of interest, by increasing backscattered efficiency. In order to enhance the ultrasound response UCAs should be engineered with narrow size distribution. In the present work PVA-shelled UCAs with controlled size and polydispersity is manufactured under varied parameters of the manufacturing protocol. It was observed that temperature of the surrounding atmosphere has major effect on the size of the UCAs, while polydispersity is regulated by geometry and speed of the disperser. Finally, the acoustic response of these microbubbles is tested using developed ultrasound test rig. The enhancement of the backscattered power of about 25 dB from a suspension of the microbubbles is observed at 5 MHz ultrasound frequency. Keeping in mind that in clinical practice ultrasound scatter from the blood is of about 30 dB weaker than scatter from surrounding tissue, introduction of novel PVA microbubbles will potentially improve diagnosis of the cardiovascular patients.

  • 444. Zhuang, C.
    et al.
    Marquez, Juan C.
    KTH, School of Technology and Health (STH), Medical Engineering, Medical sensors, signals and systems. Shanghai Jiao Tong University, China.
    Qu, H. E.
    He, X.
    Lan, N.
    A neuromuscular electrical stimulation strategy based on muscle synergy for stroke rehabilitation2015In: International IEEE/EMBS Conference on Neural Engineering, NER, IEEE Computer Society, 2015, p. 816-819Conference paper (Refereed)
    Abstract [en]

    Recent experiments have suggested that the central nervous system (CNS) makes use of muscle synergies as a neural strategy to simplify the control of a variety of movements by using a single pattern of neural command signal. This nature of muscle coordination could have great significance in the treatment and rehabilitation of upper limb impairments for hemiparetic patients post stroke. The use of neuromuscular electrical stimulation (NMES) for neural prosthetics or therapeutic applications has been demonstrated as a promising clinical intervention for stroke patients to recover motor function of the upper extremity. However, the existing NMES systems do not provide control methods for the patient to achieve an individualized and functional rehabilitation training. In this research work, muscle synergies from the flexionextension elbow antagonistic muscles were studied. Using motion information and EMG signals, muscle synergies were extracted using non-negative matrix factorization (NMF) method. Reconstructed signals obtained from the muscle synergies were then applied to the virtual arm (VA) model to test a synergy based NMES strategy. Results show close resemblance to the original elbow trajectory of normal movements and thus the feasibility to control movements in stroke patients for rehabilitation.

  • 445.
    Zomer, Lara-Britt
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Transport Science.
    Daamen, Winnie
    TU Delft.
    Meijer, Sebastiaan
    KTH, School of Technology and Health (STH), Health Systems Engineering, Health Care Logistics.
    Hoogendoorn, Serge
    TU Delft.
    Managing Crowds: The Possibilities and Limitations of Crowd Information During Urban Mass Events2015Conference paper (Refereed)
    Abstract [en]

    Thischapter,basedonamixedmethodresearchapproach,offersinsights into possibilities and limitations of using ICT measures for crowd management and distribution during urban mass events (UMEs). Based on literature, practical applications and analyses of research results, we propose crowd management should consider characteristics of both crowds and UMEs to increase information effectiveness. In relation to urban planning, results show that possibilities to influence a crowd’s behavior depend on available (and known) choice sets offered in various locations, while distances towards locations across city centers appear less important. Limitations appear to be related to scarce knowledge on what drives crowd members to adapt or adhere to their activity choice behavior. Such insights are essential for smart cities striving for an optimal use of infrastructural capacity, as both the ambiguous effects of ICT measures, as well as a crowd’s self-organizing capacity should be taken into account for delaying, solving and preventing dis- ruptions of pedestrian flows in city centers. 

  • 446. Zomer, Lara-Britt
    et al.
    Moustaid, Elhabib
    KTH, School of Technology and Health (STH), Health Systems Engineering, Health Care Logistics.
    Meijer, Sebastiaan
    KTH, School of Technology and Health (STH), Health Systems Engineering, Health Care Logistics.
    A Meta-Model for Including Social Behavior and Data into Simulation in the Smart City Context2015In: Proceedings of the 2015 Winter Simulation Conference / [ed] L. Yilmaz, W. K. V. Chan, I. Moon, T. M. K. Roeder, C. Macal, and M. D. Rossetti, 2015Conference paper (Refereed)
    Abstract [en]

    mart city management can be regarded to bridge different realms of thinking about cities, i.e., 1) the city as complex-adaptive system, 2) socio-technical operational control center and 3) multi-actor policy-making. Underpinned by different world views and theoretical bodies, integration of the three realms puts forward new demands on simulation approaches and challenges current knowledge and available technology regarding integration of sub-models across different systems. In order to support urban transportation management, a holistic approach is needed that semantically connects the three realms by incorporation of human behavior and knowledge. Combining research on knowledge management and computer science, this paper presents a novel meta-framework as socio-technical hybrid simulation language to generalize integration of simulations, gaming and data for modeling urban transportation.

  • 447.
    Zou, Hong
    et al.
    Department of Mechanical Engineering, The Ohio State University.
    Kleiven, Svein
    KTH, School of Technology and Health (STH), Neuronic Engineering.
    Schmiedeler, James P.
    Department of Mechanical Engineering, The Ohio State University.
    The Effect of Brain Mass and Moment of Inertia on Relative Brain-Skull Displacement in Low-Severity Impacts2006Conference paper (Refereed)
  • 448.
    Öhman, Maj-Britt
    et al.
    Uppsala universitet.
    Sandström, Camilla
    Umeå University.
    Thunqvist, Eva-Lotta
    KTH, School of Technology and Health (STH), Health Systems Engineering, Systems Safety and Management.
    Designing Dam Safeties: Perspectives on large scale dams within the intra-actions of technology, nature and human decision making2013In: International Commission of Large Dams, ICOLD, Seattle, 2013: International Symposium, Seattle: ICOLD , 2013Conference paper (Refereed)
    Abstract [en]

    Analyzing the intra-actions between the actors involved, this paper presents results from interviews and participatory observations with local authorities, local inhabitants, power companies representatives as well as dam operators. We argue that the Swedish model for dam safety currently is suffering from a major deficiency as the expertise and understanding of the technical constructions remain among the dam owners and that the societal authority in charge of supervising the dam owners work have no capability of achieving the same level of understanding and thus to take informed and relevant decisions. Furthermore we argue that the lack of technical understanding of dams and hydropower outside of the dam sector has become a huge threat to dam safety as state representatives and political decision makers currently allow and even encourage mining exploitation both next to high risk classified hydropower dams and even within existing hydropower reservoirs.

    We argue that the actual challenge to safeguard an increased dam safety is by bridging the gap between the multitude of different actors– engineers/operators, users, political decision makers -   in order to generate new understandings and new methodologies to deal with risk, safety and security. It is necessary to bridge the gaps between the sectors and actors involved, and that this should be done through investment in close collaboration between the dam sector and engineering research on the one hand and social sciences and humanities on the other – to ensure understandings of political decision making as well as of technical artifacts and water flows.

    The geographical focus is on two rivers – the Ume River and the Lule River in the north of Sweden. Both rivers are of major importance for national production of electricity, and the rivers are water suppliers for a large amount of inhabitants.

  • 449. Öhman, May-Britt
    et al.
    Thunqvist, Eva-Lotta
    KTH, School of Technology and Health (STH), Centres, Centre for Health and Building, CHB.
    Challenging Genocide: Decolonizing Methods against Aggressive Swedish State Colonization of Sàmi Lands and Waters2013Conference paper (Refereed)
  • 450.
    Öhman, May-Britt
    et al.
    Uppsala universitet, Centrum för Genusvetenskap.
    Thunqvist, Eva-Lotta
    KTH, School of Technology and Health (STH), Centres, Centre for Health and Building, CHB.
    Human Bodies and the Forces of Nature: Regulated Rivers, Safety and Embodied Knowledge2012In: International Commission for Large Dams International Symposium, 2012Conference paper (Refereed)
    Abstract [en]

    This paper discusses the human bodies involved in the regulated rivers, via the technology of design and operation of remote controland surveillance systems. It draws on case studies of hydropower in Sweden, both historical and current events, from studies madewithin an ongoing research project. Within current civil engineering education, training as well as within societal and company leveldecision making on large scale technical systems, the human body, with its knowledges, emotions and affections, as well as itsvulnerabilities are to a large extent disregarded. The body of the engineer/ operator is considered uninteresting and replaceable whileat the same time as it is viewed as a never failing machine. New technologies for camera surveillance and monitoring have providedopportunities to assemble data on a dam and the water flowing through it. We argue that these new technologies may contribute to adecreased dam safety, as it reinforces this paradigm of a detached human body - working like a never failing machine, always in controlof nature’sforces. We suggest that more attention is paid to the human bodies – emotions, affections and societal contexts – workingwith the design and operation of remote control and surveillance systems

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