miun.sePublikasjoner
Endre søk
Begrens søket
45678910 301 - 350 of 1597
Referera
Referensformat
• apa
• ieee
• modern-language-association-8th-edition
• vancouver
• Annet format
Fler format
Språk
• de-DE
• en-GB
• en-US
• fi-FI
• nn-NO
• nn-NB
• sv-SE
• Annet språk
Fler språk
Utmatningsformat
• html
• text
• asciidoc
• rtf
Treff pr side
• 5
• 10
• 20
• 50
• 100
• 250
Sortering
• Standard (Relevans)
• Forfatter A-Ø
• Forfatter Ø-A
• Tittel A-Ø
• Tittel Ø-A
• Type publikasjon A-Ø
• Type publikasjon Ø-A
• Eldste først
• Nyeste først
• Disputationsdatum (tidligste først)
• Disputationsdatum (siste først)
• Standard (Relevans)
• Forfatter A-Ø
• Forfatter Ø-A
• Tittel A-Ø
• Tittel Ø-A
• Type publikasjon A-Ø
• Type publikasjon Ø-A
• Eldste først
• Nyeste først
• Disputationsdatum (tidligste først)
• Disputationsdatum (siste først)
Merk
Maxantalet träffar du kan exportera från sökgränssnittet är 250. Vid större uttag använd dig av utsökningar.
• 301.
University of Brescia, Brescia, Italy.
University of Brescia, Brescia, Italy. University of Brescia, Brescia, Italy. Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för elektronikkonstruktion. University of Brescia, Brescia, Italy. University of Brescia, Brescia, Italy. University of Brescia, Brescia, Italy.
Virtual Respiratory Rate Sensors: An Example of A Smartphone-Based Integrated and Multiparametric mHealth Gateway2017Inngår i: IEEE Transactions on Instrumentation and Measurement, ISSN 0018-9456, E-ISSN 1557-9662, Vol. 66, nr 9, s. 2456-2463, artikkel-id 7949106Artikkel i tidsskrift (Fagfellevurdert)

In the last few years, several wearables appeared in the market, for fitness and healthcare applications. Such smart devices have been proposed as a possible solution for lowering the costs of healthcare, leading to the mHealth revolution. In the typical scenario, each wearable, embedding sensors, processing units and communication modules, adopts a smartphone for data collection, data displaying, and remote communication. In this paper, authors modify this paradigm simplifying the wearables (e.g., relying only on simple analog front ends and communication interfaces) and exploiting the (relatively large) computational capability of the smartphone, not only for implementing gateway features but also for processing raw biosignals as well. Several experiments verify the feasibility of the proposed approach and demonstrate that 'local' biosensor virtualization is possible, expanding possibilities of mHealth. In particular, tests have been carried out to evaluate the performance of hearth rate computation and respiratory rate virtual sensor, starting from a single-lead electrocardiogram signal.

• 302.
Univ Milano Bicocca, Milan, Italy; CNR, Milan, Italy; INFN, Milan, Italy.
CNR, Milan, Italy. CNR, Milan, Italy. CNR, Milan, Italy. Univ Milano Bicocca, Milan, Italy. Univ Milano Bicocca, Milan, Italy. CNR, IENI, Milan, Italy. Tech Univ Munich, Heinz Maier Leibnitz Zentrum MLZ, Lichtenbergstr 1, Garching, Germany. Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för elektronikkonstruktion. ESS, ERIC, Lund. ESS, ERIC, Lund; Linköping Univ, Linköping. Rutherford Appleton Lab, STFC, ISIS Facil, Didcot, Oxon, England. Rutherford Appleton Lab, STFC, ISIS Facil, Didcot, Oxon, England. ESS, ERIC, Lund. ESS, ERIC, Lund. Rutherford Appleton Lab, STFC, ISIS Facil, Didcot, Oxon, England. Tech Univ Munich, Heinz Maier Leibnitz Zentrum MLZ, Lichtenbergstr 1, Garching, Germany. CNR, IFP, Milan, Italy; ESS, ERIC, Lund.
A high-efficiency thermal neutron detector based on thin 3D (B4C)-B-10 converters for high-rate applications2018Inngår i: Europhysics letters, ISSN 0295-5075, E-ISSN 1286-4854, Vol. 123, nr 5, artikkel-id 52001Artikkel i tidsskrift (Fagfellevurdert)

new position-sensitive thermal neutron detector based on boron-coated converters has been developed as an alternative to today's standard He-3-based technology for application to thermal neutron scattering. The key element of the development is a novel 3D (B4C)-B-10 converter which has been ad hoc designed and realized with the aim of combining a high neutron conversion probability via the B-10(n, alpha)(7) Li reaction together with an efficient collection of the produced charged particles. The developed 3D converter is composed of thin aluminium grids made by a micro-waterjet technique and coated on both sides with a thin layer of( 10)B(4)C. When coupled to a GEM detector this converter allows reaching neutron detection efficiencies close to 50% at neutron wavelengths equal to 4 angstrom. In addition, the new detector features a spatial resolution of about 5 min and can sustain counting rates well in excess of 1 MHz/cm(2). The newly developed neutron detector will enable time-resolved measurements of different kind of samples in neutron scattering experiments at high flux spallation sources and can find a use in applications where large areas and custom geometries of thermal neutron detectors are foreseen.

• 303.
Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för informations- och kommunikationssystem.
User Experience Enhancement in 3D Video Conferencing2013Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave

3D video conferencing is continuously evolving to make the visual experience realistic. The main advantage of 3D video conferencing deals with the addition of depth perception which enhances the user experience. The configuration of capturing and rendering equipments and the location of scene objects play an essential role in the quality of the user experience. An incorrect configuration of equipment parameters or an inconsistent distribution of scene components could cause an uncomfortable user experience, yielding in user sickness and dizziness.

The aim of this thesis is therefore to provide the tools and methods to assure a comfortable user experience when using Ericsson’s stereoscopic 3D video conferencing system. To achieve this goal, an investigation on the capturing and rendering systems has been performed to identify possible conflicts. This investigation has shown that accommodation-convergence rivalry, comfortable viewing range and stereo framing violation are the major sources of user discomfort in 3D video conferencing.

An algorithm for continuous analysis of produced stereoscopic content has been proposed. In particular, it detects wrong equipment configuration and problematic content in real time by means of automatic adjustments or user interaction, either at initiation phase or during the call session at capturing side. To validate and evaluate the efficiency of the implemented solution, a subjective test with participation of the 3D experts has been carried out. It has been shown that the proposed solution can detect targeted problems with high accuracy and apply corrective actions. It is important to note that manual solutions are not immune to problems. Nevertheless, it has also been shown that automatic solutions can considerably compensate manual methods inconsistency and provide a comfortable user experience.

• 304.
Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för elektronikkonstruktion.
Fastighetsautomation: En projektering2018Independent thesis Basic level (professional degree), 10 poäng / 15 hpOppgave

Fastighetsautomation används för att automatisera processer i byggnader och kan avse automatisering av HVAC, belysning, säkerhetsfunktioner samt mycket mer. Det här arbetet avser en projektering av ett BAS för HVAC för cirkellokstallet i Sundsvall åt SKIFU. Projekteringen avser att ta reda på vad nuvarande system består av samt att jämföra två nya system som SKIFU valt, dessa är Schneider Electric och Regin. Metoden för att finna ut nuvarande system är att göra fältstudier på platsen samt att studera dokumentation tillhörande byggnaden. För att göra jämförelsen görs en litteraturstudie samt studie av tillverkarnas hemsidor. Det nuvarande systemet är ett Honeywell Excel 5000 och använder sig av LonTalk och BACnet för kommunikation. Systemet består av DHC, DUCar och flertalet aktorer och sensorer. De nya systemen Schneider Electric och Regin har olika kommunikationsstandarder, KNX respektive EXOline, BACnet, M-bus och Modbus. Schneider behöver inte använda DHC och DUC då alla enheter i KNX har mikrokontrollers och inte behövs styras centralt. Med KNX blir det stor flexibilitet då KNX har över 400 tillverkare av produkter som är KNX-certifierade. Regin med deras flera kommunikationsstandarder har även de stor flexibilitet men gateways kan behövas användas mellan kommunikationsstandarderna vilket kan leda till packet loss. Författaren av rapporten anser att Schneider Electric ska väljas på grunderna av att KNX används och att det i övriga fall inte skiljer sig åt mellan tillverkarna utan enheterna fungerar liknande men med olika standarder. Slutsatsen är att det BAS som är installerat är av Honeywell och om något system ska installeras så bör det vara KNX -baserat då gateways inte behövs och KNX är störst på den europeiska marknaden.

• 305. Dai, X W
Guangzhou Inst. of Energy Conversion, Chinese Academy of Sciences, China. Guangzhou Inst. of Energy Conversion, Chinese Academy of Sciences, China. Guangzhou Inst. of Energy Conversion, Chinese Academy of Sciences, China. Guangzhou Inst. of Energy Conversion, Chinese Academy of Sciences, China.
Pyrolysis of waste tires in a circulating fluidized-bed reactor2001Inngår i: Energy, ISSN 0360-5442, E-ISSN 1873-6785, Vol. 26, nr 4, s. 385-399Artikkel i tidsskrift (Fagfellevurdert)

Using a circulating fluidized bed (CFB) as the main reactor, an integrated process development unit was operated aiming at the pyrolysis of waste tires. The main chemical processes in the CFB can be divided into two zones corresponding to pyrolysis and secondary reactions. The pyrolysis of tire powder was carried out at various pyrolysis temperatures, particle sizes of tire powder and feed positions. The effects of temperature, residence time and heating rate on pyrolysis were analyzed based on the experimental data. The main trends are that (1) a long residence time contributes to secondary reactions and (2) lower temperature and heating rate favor carbonization, which reduces the oil yield. Analysis of the pyrolytic oil shows that the predominant components are aromatics, followed by alkanes, non-hydrocarbons and asphalt.

• 306.
Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för informations- och kommunikationssystem.
The Sampling Pattern Cube: A Framework for Representation and Evaluation of Plenoptic Capturing Systems2013Licentiatavhandling, monografi (Annet vitenskapelig)

Digital cameras have already entered our everyday life. Rapid technological advances have made it easier and cheaper to develop new cameras with unconventional structures. The plenoptic camera is one of the new devices which can capture the light information which is then able to be processed for applications such as focus adjustments. The high level camera properties, such as the spatial or angular resolution are required to evaluate and compare plenoptic cameras. With complex camera structures that introduce trade-offs between various high level camera properties, it is no longer straightforward to describe and extract these properties. Proper models, methods and metrics with the desired level of details are beneficial to describe and evaluate plenoptic camera properties.

This thesis attempts to describe and evaluate camera properties using a model based representation of plenoptic capturing systems in favour of a unified language. The SPC model is proposed and it describes which light samples from the scene are captured by the camera system. Light samples in the SPC model carry the ray and focus information of the capturing setup. To demonstrate the capabilities of the introduced model, property extractors for lateral resolution are defined and evaluated. The lateral resolution values obtained from the introduced model are compared with the results from the ray-based model and the ground truth data. The knowledge about how to generate and visualize the proposed model and how to extract the camera properties from the model based representation of the capturing system is collated to form the SPC framework.

The main outcomes of the thesis can be summarized in the following points: A model based representation of the light sampling behaviour of the plenoptic capturing system is introduced, which incorporates the focus information as well as the ray information. A framework is developed to generate the SPC model and to extract high level properties of the plenoptic capturing system. Results confirm that the SPC model is capable of describing the light sampling behaviour of the capturing system, and that the SPC framework is capable of extracting high level camera properties with a higher descriptive level as compared to the ray-based model. The results from the proposed model compete with those from the more elaborate wave optics model in the ranges that wave nature of the light is not dominant. The outcome of the thesis can benefit design, evaluation and comparison of the complex capturing systems.

• 307.
Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för informationsteknologi och medier.
Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för informationsteknologi och medier. Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för informationsteknologi och medier.
Extraction of the lateral resolution in a plenoptic camera using the SPC model2012Inngår i: 2012 International Conference on 3D Imaging, IC3D 2012 - Proceedings, IEEE conference proceedings, 2012, s. Art. no. 6615137-Konferansepaper (Fagfellevurdert)

Established capturing properties like image resolution need to be described thoroughly in complex multidimensional capturing setups such as plenoptic cameras (PC), as these introduce a trade-off between resolution and features such as field of view, depth of field, and signal to noise ratio. Models, methods and metrics that assist exploring and formulating this trade-off are highly beneficial for study as well as design of complex capturing systems. This work presents how the important high-level property lateral resolution is extracted from our previously proposed Sampling Pattern Cube (SPC) model. The SPC carries ray information as well as focal properties of the capturing system it models. The proposed operator extracts the lateral resolution from the SPC model throughout an arbitrary number of depth planes resulting in a depth-resolution profile. We have validated the resolution operator by comparing the achieved lateral resolution with previous results from more simple models and from wave optics based Monte Carlo simulations. The lateral resolution predicted by the SPC model agrees with the results from wave optics based numerical simulations and strengthens the conclusion that the SPC fills the gap between ray-based models and wave optics based models, by including the focal information of the system as a model parameter. The SPC is proven a simple yet efficient model for extracting the depth-based lateral resolution as a high-level property of complex plenoptic capturing system.

• 308.
Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för informations- och kommunikationssystem.
Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för informations- och kommunikationssystem. Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för informations- och kommunikationssystem.
Performance analysis in Lytro camera: Empirical and model based approaches to assess refocusing quality2014Inngår i: ICASSP, IEEE International Conference on Acoustics, Speech and Signal Processing - Proceedings, IEEE conference proceedings, 2014, s. 559-563Konferansepaper (Fagfellevurdert)

In this paper we investigate the performance of Lytro camera in terms of its refocusing quality. The refocusing quality of the camera is related to the spatial resolution and the depth of field as the contributing parameters. We quantify the spatial resolution profile as a function of depth using empirical and model based approaches. The depth of field is then determined by thresholding the spatial resolution profile. In the model based approach, the previously proposed sampling pattern cube (SPC) model for representation and evaluation of the plenoptic capturing systems is utilized. For the experimental resolution measurements, camera evaluation results are extracted from images rendered by the Lytro full reconstruction rendering method. Results from both the empirical and model based approaches assess the refocusing quality of the Lytro camera consistently, highlighting the usability of the model based approaches for performance analysis of complex capturing systems.

• 309.
Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för informationsteknologi och medier.
Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för informationsteknologi och medier. Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för informationsteknologi och medier.
The Sampling Pattern Cube: A Representation and Evaluation Tool for Optical Capturing Systems2012Inngår i: Advanced Concepts for Intelligent Vision Systems / [ed] Blanc-Talon, Jacques, Philips, Wilfried, Popescu, Dan, Scheunders, Paul, Zemcík, Pavel, Berlin / Heidelberg: Springer Berlin/Heidelberg, 2012, , s. 12s. 120-131Konferansepaper (Fagfellevurdert)

Knowledge about how the light field is sampled through a camera system gives the required information to investigate interesting camera parameters. We introduce a simple and handy model to look into the sampling behavior of a camera system. We have applied this model to single lens system as well as plenoptic cameras. We have investigated how camera parameters of interest are interpreted in our proposed model-based representation. This model also enables us to make comparisons between capturing systems or to investigate how variations in an optical capturing system affect its sampling behavior.

• 310.
Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för informations- och kommunikationssystem.
Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för informations- och kommunikationssystem. Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för informations- och kommunikationssystem. Raytrix Gmbh. Raytrix Gmbh.
Spatial resolution in a multi-focus plenoptic camera2014Inngår i: IEEE International Conference on Image Processing, ICIP 2014, IEEE conference proceedings, 2014, s. 1932-1936, artikkel-id 7025387Konferansepaper (Fagfellevurdert)

Evaluation of the state of the art plenoptic cameras is necessary for design and application purposes. In this work, spatial resolution is investigated in a multi-focus plenoptic camera using two approaches: empirical and model-based. The Raytrix R29 plenoptic camera is studied which utilizes three types of micro lenses with different focal lengths in a hexagonal array structure to increase the depth of field. The modelbased approach utilizes the previously proposed sampling pattern cube (SPC) model for representation and evaluation of the plenoptic capturing systems. For the experimental resolution measurements, spatial resolution values are extracted from images reconstructed by the provided Raytrix reconstruction method. Both the measurement and the SPC model based approaches demonstrate a gradual variation of the resolution values in a wide depth range for the multi focus R29 camera. Moreover, the good agreement between the results from the model-based approach and those from the empirical approach confirms suitability of the SPC model in evaluating high-level camera parameters such as the spatial resolution in a complex capturing system as R29 multi-focus plenoptic camera.

• 311.
Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för informations- och kommunikationssystem.
Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för informations- och kommunikationssystem. Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för informations- och kommunikationssystem. Department of Optics, University of Valencia, Spain. Department of Optics, University of Valencia, Spain.
Investigating the lateral resolution in a plenoptic capturing system using the SPC model2013Inngår i: Proceedings of SPIE - The International Society for Optical Engineering: Digital photography IX, SPIE - International Society for Optical Engineering, 2013, s. 86600T-Konferansepaper (Fagfellevurdert)

Complex multidimensional capturing setups such as plenoptic cameras (PC) introduce a trade-off between various system properties. Consequently, established capturing properties, like image resolution, need to be described thoroughly for these systems. Therefore models and metrics that assist exploring and formulating this trade-off are highly beneficial for studying as well as designing of complex capturing systems. This work demonstrates the capability of our previously proposed sampling pattern cube (SPC) model to extract the lateral resolution for plenoptic capturing systems. The SPC carries both ray information as well as focal properties of the capturing system it models. The proposed operator extracts the lateral resolution from the SPC model throughout an arbitrary number of depth planes giving a depth-resolution profile. This operator utilizes focal properties of the capturing system as well as the geometrical distribution of the light containers which are the elements in the SPC model. We have validated the lateral resolution operator for different capturing setups by comparing the results with those from Monte Carlo numerical simulations based on the wave optics model. The lateral resolution predicted by the SPC model agrees with the results from the more complex wave optics model better than both the ray based model and our previously proposed lateral resolution operator. This agreement strengthens the conclusion that the SPC fills the gap between ray-based models and the real system performance, by including the focal information of the system as a model parameter. The SPC is proven a simple yet efficient model for extracting the lateral resolution as a high-level property of complex plenoptic capturing systems.

• 312.
Angstrom Laboratory, Division of Solid-State Electronics, Uppsala University, Uppsala, Sweden .
Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för elektronikkonstruktion. Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för elektronikkonstruktion. Angstrom Laboratory, Division of Solid-State Electronics, Uppsala University, Uppsala, Sweden . Angstrom Laboratory, Division of Solid-State Electronics, Uppsala University, Uppsala, Sweden .
Antennas on Paper Using Ink-Jet Printing of Nano-Silver Particles for Wireless Sensor Networks in Train Environment2016Inngår i: Microwave and optical technology letters (Print), ISSN 0895-2477, E-ISSN 1098-2760, Vol. 58, nr 4, s. 754-759Artikkel i tidsskrift (Fagfellevurdert)

This article presents the design, manufacturing, and measurements of antennas on paper, realized using ink-jet printing of conductive inks based on nano-silver particles (nSPs). The extraction of the substrate characteristics such as the dielectric constant and dielectric loss is performed using a printed ring resonator technique. The characterization of the nSPs conductive inks assesses different parameters as sintering time and temperature. Two antennas are realized corresponding to the most common needs for wireless sensor networks in Trains Environment. The first one is a patch antenna characterized by a broadside radiation pattern and suited for operation on metallic structures. The second one is a quasi-yagi antenna, with an end fire radiation pattern and higher directivity, without requiring a metallic ground plane. Both antennas present a good matching (S11 < -20 dB and S11 < -30 dB, respectively) and acceptable efficiency (55% and 45%, respectively) for the paper substrate used at the center frequency of 2.4 GHz, corresponding to the first channel of the IEEE 802.15.4 band.

• 313.
Dept. of Computer and Systems Sciences, Stockholm University.
Dept. of Computer and Systems Sciences, Stockholm University. Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för informationsteknologi och medier.
Generalised Risk Constraints in Decision Trees with Second-Order Probabilities2012Inngår i: Advances in Economics, Risk Management, Political and Law Science / [ed] D. Pavelkova, J. Strouhal, M. Pasekova, WSEAS Press , 2012, s. 376-383Konferansepaper (Fagfellevurdert)

Recently, representations and methods analysing decision problems where probabilities and values (utilities) are associated with belief distributions over them (second order representations) have been suggested. In this paper we present an approach to how imprecise information can be modelled by means of second-order distributions and how a risk evaluation process can be elaborated by integrating procedures for numerically impreciseprobabilities and utilities. We discuss some shortcomings in the use of the principle of maximising the expectedutility and of utility theory in general, and offer remedies by the introduction of supplementary decision rules based on a concept of risk constraints taking advantage of second-order distributions.

• 314.
Dept. of Computer and Systems Sciences, Stockholm University.
Dept. of Computer and Systems Sciences, Stockholm University. Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för informations- och kommunikationssystem. Dept. of Computer and Systems Sciences, Stockholm University.
Weighting Under Ambiguous Preferences and Imprecise Differences in a Cardinal Rank Ordering Process2013Inngår i: International Journal of Computational Intelligence Systems, ISSN 1875-6883, Vol. 7, nr 1, s. 105-112Artikkel i tidsskrift (Fagfellevurdert)

The limited amount of good tools for supporting elicitation of preference information in multi-criteria decision analysis (MCDA) causes practical problem. In our experiences, this can be remedied by allowing more relaxed input statements from decision-makers, causing the elicitation process to be less cognitively demanding. Furthermore, it should not be too time consuming and must be able to actually use of the information the decision-maker is able to supply. In this paper, we propose a useful weight elicitation method for MAVT/MAUT decision making, which builds on the ideas of rank-order methods, but increases the precision by adding numerically imprecise cardinal information as well.

• 315.
Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för elektronikkonstruktion.
Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för elektronikkonstruktion.
GaN Based Converters for Battery Charging Application of Electric Vehicle2019Inngår i: IECON2019: 45th Annual Conference of the IEEE Industrial Electronics Society, IEEE, 2019Konferansepaper (Fagfellevurdert)

The high frequency capability and low on-state losses of Gallium Nitride (GaN) transistors offer the potential to increase converter efficiency and/or reduce heatsink and passive component size. This paper investigates the use of GaN technology to enhance the performance of power factor correction (PFC) and LLC converters for battery charging applications. First the efficiency performance of non-isolated PFC converters using GaN transistors is compared by simulation, the asymmetric bridgeless PFC converter is shown to achieve the best efficiency, with a predicted figure of 99% in a 1MHz, 200W design. The predictions are validated by an experimental prototype using a GS66502B, GaN Systems E-mode GaN transistor. Then the efficiency comparison of the PFC and LLC converter using GaN devices for battery charging applications is included in the paper. The experimental results of the PFC converter with GaN devices are also included. Additionally, this paper includes the analysis and design of a common mode input filter for the GaN-based high frequency converters for battery charging application. The size of both the converters using GaN devices is reduced by 40% than the converters based on Si devices. The switching loss comparison of GaN and Si devices are also included in the paper.

• 316.
Department of Physics and Astronomy, University of Glasgow, Glasgow G12 8QQ, UK.
Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för informationsteknologi och medier. Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för informationsteknologi och medier.
Limitations to flat-field correction methods when using an X-ray spectrum2003Inngår i: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, ISSN 0168-9002, E-ISSN 1872-9576, s. 146-150Artikkel i tidsskrift (Fagfellevurdert)

Flat-field correction methods are implemented in order to eliminate non-uniformities in X-ray imaging sensors. If the compensation is perfect, then the remaining variations result from noise over the detector area. The efficiency of the compensation is reduced when an object is placed in the beam. A principle cause of this effect is believed to be the spectrum hardening caused by the object. In a normal application the correction factors are calculated for a certain spectrum, meaning that the average of the correction for the individual photon energies are used. If the composition of the spectrum changes the correction factor will also change. In this paper, we present a theory for the sensitivity of the gain constants on X-ray spectra. The theory is supported by experimental data obtained with X-ray spectra and monochromatic X-rays.

• 317.
University of Perugia, Perugia, Italy.
University of Perugia, Perugia, Italy. Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för elektronikkonstruktion. University of Brescia, Brescia, Italy. University of Brescia, Brescia, Italy.
Performance Assessment of Chirp-Based Time Dissemination and Data Communications in Inductively Coupled Links2017Inngår i: IEEE Transactions on Instrumentation and Measurement, ISSN 0018-9456, E-ISSN 1557-9662, Vol. 66, nr 9, s. 2474-2482, artikkel-id 7930481Artikkel i tidsskrift (Fagfellevurdert)

Advantages of inductively coupled links for short-range communications are well known. Recently, they gained popularity as a viable solution for wireless power transmission. Interesting to notice that data communication capability is required as well, mainly for coordinating the transfer process. In this paper, the authors address the use of chirp signaling over inductively coupled links for both time dissemination and data communications. Such an approach extends field of applications, including data acquisition and instrumentation that are used in industrial automation. The effectiveness of the proposed approach is verified with extensive simulations and using a proof-of-concept prototype. Despite the prototype simplicity, jitter on the synchronizing reference signal is in the order of few microseconds and the bit error rate, over a short distance, is negligible.

• 318.
NTNU, Trondheim, Norway.
Acreo Swedish ICTAB, Kista, Sweden. Acreo Swedish ICTAB, Kista, Sweden. Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för informations- och kommunikationssystem. Acreo Swedish ICTAB, Kista, Sweden. Acreo Swedish ICTAB, Kista, Sweden. Volvo Cars AB, Gothenburg, Sweden. Volvo Cars AB, Gothenburg, Sweden.
Influence of high ambient illuminance and display luminance on readability and subjective preference2015Inngår i: Proceedings of SPIE - The International Society for Optical Engineering / [ed] Rogowitz, B., Pappas, T. N., and de Ridder, H., Bellingham, WA, USA: SPIE - International Society for Optical Engineering, 2015, Vol. 9394, s. Art. no. 93941E-Konferansepaper (Fagfellevurdert)

Many devices, such as tablets, smartphones, notebooks, fixed and portable navigation systems are used on a (nearly) daily basis, both in in- and outdoor environments. It is often argued that contextual factors, such as the ambient illuminance in relation to characteristics of the display (e.g., surface treatment, screen reflectance, display luminance...) may have a strong influence on the use of such devices and corresponding user experiences. However, the current understanding of these influence factors is still rather limited. In this work, we therefore focus in particular on the impact of lighting and display luminance on readability, visual performance, subjective experience and preference. A controlled lab study (N=18) with a within-subjects design was performed to evaluate two car displays (one glossy and one matte display) in conditions that simulate bright outdoor lighting conditions. Four ambient luminance levels and three display luminance settings were combined into 7 experimental conditions. More concretely, we investigated for each display: (1) whether and how readability and visual performance varied with the different combinations of ambient luminance and display luminance and (2) whether and how they influenced the subjective experience (through self-reported valence, annoyance, visual fatigue) and preference. The results indicate a limited, yet negative influence of increased ambient luminance and reduced contrast on visual performance and readability for both displays. Similarly, we found that the self-reported valence decreases and annoyance and visual fatigue increase as the contrast ratio decreases and ambient luminance increases. Overall, the impact is clearer for the matte display than for the glossy display.

• 319.
Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för elektronikkonstruktion.
Using Fiber Bragg Grating for High Frequency Measurements of Acoustic Waves2018Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave

Fiber optical sensors are a new type of sensor-technology which has been in development for over 30 years, and the interest for the fiber technology has increased exponentially. The reason for this is because of its many advantages such as; electromagnetic immunity, size and weight reductions, and cost reduction. Even though the fiber optic sensor has many advantages, it still faces other challenges. A fiber optical sensor can for example be used to measure acoustic waves, which is a typical application for the sensor. However, one of the challenges is that the fiber optic sensor can be disturbed by an unknown thermal fluctuation. In this project we will develop technology for a control algorithm which will compensate for this unknown thermal fluctuation. During this project the fiber optical sensor; Fiber Bragg Grating, will be used to measure acoustic waves on a steel plate. For initial test a tuneable laser diode has been used, which then was be replaced with a superluminescent diode and a reference Fiber Bragg Grating. The results were that it was possible to measure acoustic waves with a tuneable laser diode. However when replacing the laser diode with a superluminescent diode and a reference Fiber Bragg Grating, the optical power was too low for the photodetector to

measure any change in optical power.

• 320. Deakin Crick, Ruth
Mittuniversitetet, Lärarutbildning, Institutionen för utbildningsvetenskap.
Developing an instrument to measure learning to learn: Paper presented at the Association for Educational Assessment Europe 8th Annual Conference in Stockholm in November 20072007Konferansepaper (Fagfellevurdert)

There is a growing interest in learning to learn in a European context. European Union initiatives have resulted in describing the competence of learning to learn in the framework for competencies for lifelong learning. Related to this has also been a wish to find ways to measure learning to learn. An Expert Group initiated by the European Commission developed a proposal to organise a pilot project on learning to learn. The group identified three interesting research projects which could be used in the further work to develop a European pilot study on learning to learn: an instrument to test learning to learn developed by the University of Helsinki, the Effective Lifelong Learning Inventory developed by the University of Bristol and the tests on cross-curricular skills developed by the University of Amsterdam. The Expert Group also proposed a framework on learning to learn. The framework was based on the assumption, proposed in the definition on learning to learn decided by the Education Council and the European Parliament, that this key competence can be defined as containing two dimensions; a cognitive and an affective (or belief) part. Under each dimension a number of subscales, based on existing subscales in the tests which have been developed in the research project mentioned above, were developed. A working group containing the authors of this paper was asked by the Expert Group to develop a test on learning to learn. This group has developed a draft instrument. The instrument has been constructed to correspond to the earlier developed framework. This paper describes how the work to construct this instrument has proceeded.

• 321.
European Spallat Source ESS AB, S-22100 Lund, Sweden.
Univ Copenhagen, Niels Bohr Inst, DK-2100 Copenhagen, Denmark. Univ Copenhagen, Niels Bohr Inst, DK-2100 Copenhagen, Denmark. Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för elektronikkonstruktion. European Spallat Source ESS AB, S-22100 Lund, Sweden.
A design study of VOR: A versatile optimal resolution chopper spectrometer for the ESS2015Inngår i: EPJ Web of Conferences, EDP Sciences, 2015, Vol. 83Konferansepaper (Fagfellevurdert)

VOR, the versatile optimal resolution chopper spectrometer, is designed to probe dynamic phenomena that are currently inaccessible for inelastic neutron scattering due to flux limitations. VOR is a short instrument by the standards of the European Spallation Source (ESS), 30.2 m moderator to sample, and provides instantaneous access to a broad dynamic range, 1-120 meV within each ESS period. The short instrument length combined with the long ESS pulse width enables a quadratic flux increase, even at longer wavelengths, by relaxing energy resolution from ΔE/E = 1% up to ΔE/E = 7%. This is impossible both on a long chopper spectrometer at the ESS and with instruments at short pulsed sources. In comparison to current day chopper spectrometers, VOR can offer an order of magnitude improvement in flux for equivalent energy resolutions, ΔE/E = 1-3%. Further relaxing the energy resolution enables VOR to gain an extra order of magnitude in flux. In addition, VOR has been optimised for repetition rate multiplication (RRM) and is therefore able to measure, in a single ESS period, 6-14 incident wavelengths, across a wavelength band of 9 Å with a novel chopper configuration that transmits all incident wavelengths with equivalent counting statistics. The characteristics of VOR make it a unique instrument with capabilities to access small, limited-lifetime samples and transient phenomena with inelastic neutron scattering.

• 322.
Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för informationsteknologi och medier.
Elastic interconnection micro contact stuctures-manufacture and characterisation2004Licentiatavhandling, monografi (Annet vitenskapelig)

...The task that was put to the author of this thesis was to find solutions for manufacturing of single elastic micro bump contacts as well as complete elastic sockets and interconnections down to the carrier substrate. Use of more or less standard equipment and methods in electronic industry was a demand too. The casting mold was made in Si by anisotropic wet etching of Si wafers in KOH, and in order to manage and keep preferred distance between casting mold and the currier substrate small columns of SU 8 photo resist were made on the mold as well. For prevention of silicone elastomer sticking to the mold, Parylene was deposited on to the mold. Additionally, making of via holes is treated in this work. Two techniques were tried practically. Laser drilling has shown some potential but RIE of silicone elastomer was found to be more useful so far. Deposition of required metal layers was realized by sputtering and patterning was conducted by applying electro plated photo resist and exposing in a low divergence light mask aligner. Some limited characterization of manufactured elastic micro bump contacts by measuring their contact resistance is also reported. Some advantages of elastic micro bump contact based structures relative to already existing similar interconnection techniques is discussed. Some discussions concerning remaining technological problems and thin film contact resistance estimation issues are presented as well as the promising results, up to 45 000 contact points per cm2, achieved by scaling down the structures.

• 323.
Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för informationsteknologi och medier.
Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för informationsteknologi och medier. Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för informationsteknologi och medier.
Manufacturing of Via Holes in Silicone ElastomerManuskript (Annet (populærvitenskap, debatt, mm))

In this work a possibility of making via holes in silicone elastomer was investigated. The methods that were taken into consideration were punching, mechanical drilling, laser drilling and RIE. Laser drilling and RIE were found to be viable and both were tried. Laser drilling of silicone elastomer has shown a big problem with burnt residues and has to be investigated much further to be usable. RIE of silicone elastomer is reported in this work. Several phenomena were observed. The etch-residues can be removed by washing them away in an ultra sonic water bath and subsequently totally removed by using a lift-off process based on wet Cu etch. A good anisotropy was achieved by applying CF4 plasma. Gradually broadening of the openings in the etch mask has contributed to a favorable etch profile and thus easier metallization of side-walls of via holes.

• 324.
Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för informationsteknologi och medier.
Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för informationsteknologi och medier.
Measurement of electrical parameters using Mixed-Signal Test Bus, IEEE Std. 1149.42001Rapport (Annet vitenskapelig)
• 325.
Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för informationsteknologi och medier.
Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för informationsteknologi och medier.
Measurement of Electrical Parameters Using Mixed-Signal Test Bus, IEEE Std. 1149.42005Inngår i: Measurement, ISSN 0263-2241, Vol. 37, nr 3, s. 260-277Artikkel i tidsskrift (Fagfellevurdert)

Test Access Port and Boundary-Scan Architecture, IEEE Std. 1149.1, was developed to ease the test of printed circuit board assemblies (PCBAs). The development of packaging technology and the increasing functionality of a circuit have made traditional testing methods, such as in-circuit tests and functional testing through edge connectors much more difficult or even impossible. Mixed-Signal Test Bus, IEEE Std. 1149.4, which is a further development of IEEE Std. 1149.1 has been developed to enable the testing of analog components and analog interconnects on PCBAs. IEEE Std. 1149.4 compliant circuits contain an analog bus and analog switches. Techniques applicable to the measurement of impedances via IEEE Std. 1149.4 compliant circuits are presented. A filter has been tested and the results are promising. It has been shown by both measurement and simulation that switching impedances can be managed in such a manner that the influence of deviations from their nominal value can be estimated.

• 326.
Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för informationsteknologi och medier.
Web application development with .NET: 3-tier architecture2012Independent thesis Basic level (degree of Bachelor), 10 poäng / 15 hpOppgave

The reason for performing this project work is to develop a Web application for the Student Union of Mid Sweden University applying the modern and comprehensive Microsoft .NET framework platform architecture. At present, the existing web application is divided into several modules which are built of server‐side scripting language technique and an open source database. The customer would like to develop the entire web applications using the Microsoft development tools and technologies in order to determine the possible benefit which could be obtained in terms of cost, maintenance, flexibility and the security perspective issues and also in terms of user friendly interactions options for all the involving partners in an effective way. The primary aim for the project is to start building a bookstore module for the Students Union that is responsible for selling literature to the students at the University. The module will also be integrated into a database system into which an administrator, a member of staff working in the Student Union, will be able to add a new book when it arrives and also update or delete if necessary later on. In addition to this module application all the book’s details belong to a certain category viewable to the students. The other part of this project work is aiming at finding a pattern similar to the bookstore module in which ordinary users can authenticate them towards a database and be able to add their curriculum vitae data entry and update it at a later stage as required.

• 327.
Univ. of Salerno.
Univ. of Salerno. Univ. of Salerno. Univ. of Salerno.
A vision system for the online quality monitoring of industrial manufacturing2017Inngår i: Optics and lasers in engineering, ISSN 0143-8166, E-ISSN 1873-0302, Vol. 89, s. 162-168Artikkel i tidsskrift (Fagfellevurdert)

The design of an image based measurement system for the online inspection of electromechanical parts is described. A two-camera architecture is introduced in order to highlight all the required details involved in the measurements. The design takes into account both the interfacing and the real-time issues that assure an effective online operation. The description of the measurement system and the corresponding installation on the production line points out a methodological approach to the design of these kinds of measurement systems. The paper provides details about the algorithms for the localization and the measurement of the required quantities, as well as the calibration procedure and the error correction. Experimental tests for the performance evaluation are presented and discussed in terms of timing and accuracy.

• 328.
Univ. of Salerno.
Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för elektronikkonstruktion. Univ. of Salerno. Univ. of Salerno. Univ. of Salerno. Univ. of Cassino.
I3DermoscopyApp: Hacking Melanoma thanks to IoT technologies2017Inngår i: Proceedings of the 50th Hawaii International Conference on System Sciences 2017, 2017, s. 3587-3596Konferansepaper (Fagfellevurdert)

The paper introduces I3DermoscopyApp, a new declination of the Internet of Things (IoT) paradigm, designed to allow the early detection of melanoma. Even though artificial intelligence programs cannot outperform the diagnostic accuracy of expert dermatologists yet, they reveal to be very useful in providing second opinions to physicians with short clinical experience, thus improving significantly their diagnostic performance. Following this trend, an original integration of mobile app technology and well-known image processing algorithms allows the automatic analysis of pigmented skin lesions to help physicians apply a diagnostic method (Seven Point Check List) based on dermoscopy. The web-based platform makes the physician able to: i) store digital images captured by smartphones featured with a dermatoscope; ii) measure morphological and chromatic parameters of the skin lesion; iii) make a diagnostic decision according to the Seven Point Checklist method. \ \ A detailed description of the adopted techniques, together with the first validation results are reported.

• 329.
Hungarian Acad Sci, Budapest, Hungary; European Spallat Source ESS ERIC, Lund; Budapest Univ Technol & Econ, Budapest, Hungary.
European Spallat Source ESS ERIC, Lund. Oak Ridge Natl Lab, Oak Ridge, TN USA. Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för elektronikkonstruktion. European Spallat Source ESS ERIC, Lund. European Spallat Source ESS ERIC, Lund. European Spallat Source ESS ERIC, Lund. Hungarian Acad Sci, Budapest, Hungary; Budapest Univ Technol & Econ, Budapest, Hungary.
Scattered neutron background in thermal neutron detectors2018Inngår i: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, ISSN 0168-9002, E-ISSN 1872-9576, Vol. 902, s. 173-183Artikkel i tidsskrift (Fagfellevurdert)

Inelastic neutron scattering instruments require very low background; therefore the proper shielding for suppressing the scattered neutron background, both from elastic and inelastic scattering is essential. The detailed understanding of the background scattering sources is required for effective suppression. The Multi-Grid thermal neutron detector is an Ar/CO2 gas filled detector with a (B4C)-B-10 neutron converter coated on aluminium substrates. It is a large-area detector design that will equip inelastic neutron spectrometers at the European Spallation Source (ESS). To this end a parameterised Geant4 model is built for the Multi-Grid detector. This is the first time thermal neutron scattering background sources have been modelled in a detailed simulation of detector response. The model is validated via comparison with measured data of prototypes installed on the IN6 instrument at ILL and on the CNCS instrument at SNS. The effect of scattering originating in detector components is smaller than effects originating elsewhere.

• 330.
Hungaritm Acad Sci, Ctr Energy Res, Budapest, Hungary.
European Spallat Source ESS ERIC, Lund. Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för elektronikkonstruktion. European Spallat Source ESS ERIC, Lund. Hungaritm Acad Sci, Ctr Energy Res, Budapest, Hungary. Budapest Univ Technol & Econ, Inst Nucl Tech, Budapest, Hungary.
Neutron activation and prompt gamma intensity in Ar/CO2-filled neutron detectors at the European Spallation Source2017Inngår i: Applied Radiation and Isotopes, ISSN 0969-8043, E-ISSN 1872-9800, Vol. 128, s. 275-286Artikkel i tidsskrift (Fagfellevurdert)

Monte Carlo simulations using MCNP6.1 were performed to study the effect of neutron activation in Ar/CO2 neutron detector counting gas. A general MCNP model was built and validated with simple analytical calculations. Simulations and calculations agree that only the Ar-40 activation can have a considerable effect. It was shown that neither the prompt gamma intensity from the Ar-40 neutron capture nor the produced Ar-41 activity have an impact in terms of gamma dose rate around the detector and background level.

• 331.
European Spallation Source ESS ERIC, Lund.
European Spallation Source ESS ERIC, Lund. Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för elektronikkonstruktion. Hungarian Academy of Sciences, Centre for Energy Research, Budapest, Hungary. Hungarian Academy of Sciences, Centre for Energy Research, Budapest, Hungary.
Shielding optimization study for 10b-based large area neutron detectors with detailed geant4 model2017Inngår i: 2016 IEEE Nuclear Science Symposium, Medical Imaging Conference and Room-Temperature Semiconductor Detector Workshop, NSS/MIC/RTSD 2016, Institute of Electrical and Electronics Engineers (IEEE), 2017, Vol. 2017-January, artikkel-id 8069784Konferansepaper (Fagfellevurdert)

The European Spallation Source (ESS) sets the scope on replacing 3He tube detectors where it is reasonably achievable, consequently advanced neutron detectors require a signal-To-noise (S/N) ratio high enough to be competitive with 3He tubes and satisfy scientific requirements. Advanced local shielding could provide the improved S/N. The objective of the current study is to create a tool that can be used during the shielding optimization process. The study is performed with Monte-Carlo simulations using a Geant4 version extended with NXSG4, that is capable to handle the crystal structure of specific materials, therefore the effects of neutron absorption, coherent and incoherent scattering were simulated. Validation of the extended Geant4 code, developed at ESS is also part of the current study by comparing the simulated results with analytical calculations. A detailed and realistic model of the state-of-The-Art Multi-Grid detector has been implemented, as it is almost the only prototype with published data on scattering effects. Simulations were performed for appropriate shielding materials with various monoenergetic neutron beams.A robust tool has been developed that could be effectively used to arise the S/N via optimizing the detector shielding for specific setups and requirements for all inelastic instruments.

• 332.
Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för informations- och kommunikationssystem.
Development of interactive entertainment system for Din Tur buses: Håll Platsen2015Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave

Public transport organizations, such as Din Tur, require affordable modern solutions to improve their public image and passenger satisfaction. An easy way to create positive associations in people is to provide either useful services or, preferably, entertainment. This report covers the design, development and evaluation of an entertainment system – consisting of a smartphone game, a cloud-hosted backend, and a supporting on-bus hardware system – with the objective of making Din Tur's bus service seem more modern and appealing. The smartphone game, “Håll Platsen”, is developed in Unity game engine, focuses on providing brief entertainment during bus commutes, and incorporates gamification design elements. The Python-based back-end resides in Google's App Engine and Datastore platforms, and provides a unified virtual game environment enabling player cooperation and competition. The prototype on-bus hardware system uses the Raspberry Pi as a Light-Emitting Diode control system to supply real-world feedback of the game's virtual environment. The systems incorporate real-world busstop positioning, player location, online mapping services, team location-control mechanics, reflex-based minigames, player progression mechanics, and mobile-focused design. The resulting system can be useful in estimating public response to non-standard “smart” promotion methods, the use of games to improve everyday routines (i.e. commuting), and serve as a basis for further research in human & smart-technology interaction.

• 333.
Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för informationssystem och –teknologi.
Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för informationssystem och –teknologi. RISE Research Institutes of Sweden, Division ICT - Acreo. Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för informationssystem och –teknologi. Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för informationssystem och –teknologi. Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för informationssystem och –teknologi. Alkit Communications AB. HIAB AB.
View Position Impact on QoE in an Immersive Telepresence System for Remote Operation2019Inngår i: 2019 Eleventh International Conference on Quality of Multimedia Experience (QoMEX), IEEE, 2019, s. 1-3Konferansepaper (Fagfellevurdert)

In this paper, we investigate how different viewing positions affect a user's Quality of Experience (QoE) and performance in an immersive telepresence system. A QoE experiment has been conducted with 27 participants to assess the general subjective experience and the performance of remotely operating a toy excavator. Two view positions have been tested, an overhead and a ground-level view, respectively, which encourage reliance on stereoscopic depth cues to different extents for accurate operation. Results demonstrate a significant difference between ground and overhead views: the ground view increased the perceived difficulty of the task, whereas the overhead view increased the perceived accomplishment as well as the objective performance of the task. The perceived helpfulness of the overhead view was also significant according to the participants.

• 334.
Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för informations- och kommunikationssystem.
Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för informations- och kommunikationssystem. Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för informations- och kommunikationssystem.
Assessment of Multi-Camera Calibration Algorithms for Two-Dimensional Camera Arrays Relative to Ground Truth Position and Direction2016Inngår i: 3DTV-Conference, IEEE Computer Society, 2016, artikkel-id 7548887Konferansepaper (Fagfellevurdert)

Camera calibration methods are commonly evaluated on cumulative reprojection error metrics, on disparate one-dimensional da-tasets. To evaluate calibration of cameras in two-dimensional arrays, assessments need to be made on two-dimensional datasets with constraints on camera parameters. In this study, accuracy of several multi-camera calibration methods has been evaluated on camera parameters that are affecting view projection the most. As input data, we used a 15-viewpoint two-dimensional dataset with intrinsic and extrinsic parameter constraints and extrinsic ground truth. The assessment showed that self-calibration methods using structure-from-motion reach equal intrinsic and extrinsic parameter estimation accuracy with standard checkerboard calibration algorithm, and surpass a well-known self-calibration toolbox, BlueCCal. These results show that self-calibration is a viable approach to calibrating two-dimensional camera arrays, but improvements to state-of-art multi-camera feature matching are necessary to make BlueCCal as accurate as other self-calibration methods for two-dimensional camera arrays.

• 335.
Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för informationssystem och -teknologi.
Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för informationssystem och -teknologi. Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för informationssystem och -teknologi.
Modeling Depth Uncertainty of Desynchronized Multi-Camera Systems2017Inngår i: 2017 International Conference on 3D Immersion (IC3D), IEEE, 2017Konferansepaper (Fagfellevurdert)

Accurately recording motion from multiple perspectives is relevant for recording and processing immersive multi-media and virtual reality content. However, synchronization errors between multiple cameras limit the precision of scene depth reconstruction and rendering. In order to quantify this limit, a relation between camera de-synchronization, camera parameters, and scene element motion has to be identified. In this paper, a parametric ray model describing depth uncertainty is derived and adapted for the pinhole camera model. A two-camera scenario is simulated to investigate the model behavior and how camera synchronization delay, scene element speed, and camera positions affect the system's depth uncertainty. Results reveal a linear relation between synchronization error, element speed, and depth uncertainty. View convergence is shown to affect mean depth uncertainty up to a factor of 10. Results also show that depth uncertainty must be assessed on the full set of camera rays instead of a central subset.

• 336. Djukic, D.
Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för informationsteknologi och medier.
Preisach-type hysteresis modelling in Bi-2223 tapes1997Inngår i: Applied Superconductivity 1997.: Proceedings of EUCAS 1997 Third European Conference on Applied Superconductivity, Vol. 2, 1997, s. 1409-1412Konferansepaper (Annet vitenskapelig)
• 337.
Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för informationsteknologi och medier.
Design and Construction Of A Paper Thin Magnetostatic Loudspeaker: using Arduino Mega 2560, MusicShield v1.13 and MPR1212012Independent thesis Basic level (degree of Bachelor), 10 poäng / 15 hpOppgave

This focus of this report is on design and the aim is to build a magnetostatic speaker and a music loudspeaker from scratch by assembling the sensors together and thus, making a simple but very thin foil loudspeaker. The Arduino sensor is programmed in C language in order to make the capaci-tive sensor to have the ability to control the functions of the music player and LEDs.At the end of the process, the product will be able to play music through the thin loudspeaker by touching the capacitive sensor.

• 338.
Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för data- och systemvetenskap.
End-to-End Quality of Service Guarantees for Wireless Sensor Networks2015Doktoravhandling, med artikler (Annet vitenskapelig)

Wireless sensor networks have been a key driver of innovation and societal progressover the last three decades. They allow for simplicity because they eliminate ca-bling complexity while increasing the flexibility of extending or adjusting networksto changing demands. Wireless sensor networks are a powerful means of fillingthe technological gap for ever-larger industrial sites of growing interconnection andbroader integration. Nonetheless, the management of wireless networks is difficultin situations wherein communication requires application-specific, network-widequality of service guarantees. A minimum end-to-end reliability for packet arrivalclose to 100% in combination with latency bounds in the millisecond range must befulfilled in many mission-critical applications.The problem addressed in this thesis is the demand for algorithmic support forend-to-end quality of service guarantees in mission-critical wireless sensor networks.Wireless sensors have traditionally been used to collect non-critical periodic read-ings; however, the intriguing advantages of wireless technologies in terms of theirflexibility and cost effectiveness justify the exploration of their potential for controland mission-critical applications, subject to the requirements of ultra-reliable com-munication, in harsh and dynamically changing environments such as manufactur-ing factories, oil rigs, and power plants.This thesis provides three main contributions in the scope of wireless sensor net-works. First, it presents a scalable algorithm that guarantees end-to-end reliabilitythrough scheduling. Second, it presents a cross-layer optimization/configurationframework that can be customized to meet multiple end-to-end quality of servicecriteria simultaneously. Third, it proposes an extension of the framework used toenable service differentiation and priority handling. Adaptive, scalable, and fast al-gorithms are proposed. The cross-layer framework is based on a genetic algorithmthat assesses the quality of service of the network as a whole and integrates the phys-ical layer, medium access control layer, network layer, and transport layer.Algorithm performance and scalability are verified through numerous simula-tions on hundreds of convergecast topologies by comparing the proposed algorithmswith other recently proposed algorithms for ensuring reliable packet delivery. Theresults show that the proposed SchedEx scheduling algorithm is both significantlymore scalable and better performing than are the competing slot-based schedulingalgorithms. The integrated solving of routing and scheduling using a genetic al-vvigorithm further improves on the original results by more than 30% in terms of la-tency. The proposed framework provides live graphical feedback about potentialbottlenecks and may be used for analysis and debugging as well as the planning ofgreen-field networks.SchedEx is found to be an adaptive, scalable, and fast algorithm that is capa-ble of ensuring the end-to-end reliability of packet arrival throughout the network.SchedEx-GA successfully identifies network configurations, thus integrating the rout-ing and scheduling decisions for networks with diverse traffic priority levels. Fur-ther, directions for future research are presented, including the extension of simula-tions to experimental work and the consideration of alternative network topologies.

• 339.
Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för informationsteknologi och medier.
Finding Optimal Size TDMA Schedules using Integer ProgrammingManuskript (preprint) (Annet vitenskapelig)

The problem of finding a shortest TDMA is formally described as anInteger Program (IP). A brief user manual explains how the attached implementation can be used to find an optimal size TDMA for any givenWSN and routing table, fulfilling the validity criteria.

• 340.
Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för informationsteknologi och medier.
InPUT: The Intelligent Parameter Utilization Tool2012Inngår i: GECCO Companion 12: Proceedings of the fourteenth international conference on Genetic and evolutionary computation conference companion, New York, NY, USA: ACM Press, 2012, s. 149-156Konferansepaper (Fagfellevurdert)

Computer experiments are part of the daily business formany researchers within the area of computational intelligence. However, there is no standard for either human orcomputer readable documentation of computer experiments.Such a standard could considerably improve the collaboration between experimental researchers, given it is intuitiveto use. In response to this deficiency the Intelligent Param-eter Utilization Tool ( InPUT ) is introduced. InPUT offers ageneral and programming language independent format forthe definition of parameters and their ranges. It providesservices to simplify the implementation of algorithms andcan be used as a substitute for input mechanisms of existing frameworks. InPUT reduces code-complexity and increases the reusability of algorithm designs as well as the reproducibility of experiments. InPUT is available as open-source for Java and this will soon also be extended to C++, two ofthe predominant languages of choice for the development ofevolutionary algorithms.

• 341.
Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för data- och systemvetenskap.
Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för informations- och kommunikationssystem. Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för informations- och kommunikationssystem.
Challenges for the use of data aggregation in industrial Wireless Sensor Networks2015Inngår i: IEEE International Conference on Automation Science and Engineering, IEEE Computer Society, 2015, s. 138-144Konferansepaper (Fagfellevurdert)

The provision of quality of service for Wireless Sensor Networks is more relevant than ever now where wireless solutions with their flexibility advantages are considered for the extension/substitution of wired networks for a multitude of industrial applications. Scheduling algorithms that give end-to-end guarantees for both reliability and latency exist, but according to recent investigations is the achieved quality of service insufficient for most control applications. Data aggregation is an effective tool to significantly improve on end-to-end contention and energy efficiency compared to single packet transmissions. In practice, though, it is not extensively used for process data processing on the MAC layer. In this paper, we outline the challenges for the use of data aggregation in Industrial Wireless Sensor Networks. We further extend SchedEx, a reliability-aware scheduling algorithm extension, for packet aggregation. Our simulations for scheduling algorithms from the literature show its great potential for industrial applications. Features for the inclusion of data aggregation into industrial standards such as WirelessHART are suggested, and remaining open issues for future work are presented and discussed.

• 342.
Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för data- och systemvetenskap.
Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för informations- och kommunikationssystem. Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för informations- och kommunikationssystem.
Latency Improvement Strategies for Reliability-Aware Scheduling in Industrial Wireless Sensor Networks2015Inngår i: International Journal of Distributed Sensor Networks, ISSN 1550-1329, E-ISSN 1550-1477, artikkel-id 178368Artikkel i tidsskrift (Fagfellevurdert)

In this paper, we propose novel strategiesfor end-to-end reliability-aware scheduling in Industrial WirelessSensor Networks (IWSN). Because of stringent reliability requirements inindustrial applications where missed packets may have disastrous or lethalconsequences, all IWSN communication standards are based on TimeDivision Multiple Access (TDMA), allowing for deterministic channel access onthe MAC layer. We therefore extend an existing generic and scalablereliability-aware scheduling approach by name SchedEx. SchedEx has proven toquickly produce TDMA schedules that guarantee auser-defined end-to-end reliability level $\underline\rho$ for all multi-hopcommunication in a WSN. Moreover, SchedEx executes orders of magnitude fasterthan recent algorithms in the literature while producing schedules withcompetitive latencies.We generalize the original problem formulation from single-channel tomulti-channel scheduling and propose a scalable integration into the existingSchedEx approach.We further introduce a novel optimal bound that produces TDMAschedules with latencies around 20\% shorter than the original SchedExalgorithm. Combining the novel strategies with multiple sinks, multiplechannels, and the introduced optimal bound, we could through simulationsverify latency improvements by almost an order of magnitude, reducingthe TDMA super-frame execution times from tens of seconds to seconds only, whichallows for a utilization of SchedEx for many time-critical control applications.

• 343.
Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för data- och systemvetenskap.
Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för informations- och kommunikationssystem. Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för informations- och kommunikationssystem.
A Reliability-Aware Cross-layer Optimization Framework for Wireless Sensor Networks.Manuskript (preprint) (Annet vitenskapelig)

One of the biggest obstacles for a broad deploymentof Wireless Sensor Networks for industrial applications is the dif-ficulty to ensure end-to-end reliability guarantees while providingas tight latency guarantees as possible. In response, we proposea novel centralized optimization framework for Wireless SensorNetworks that identifies TDMA schedules and routing combi-nations in an integrated manner. The framework is shown toguarantee end-to-end reliability for all events send in a schedulingframe while minimizing the delay of all packet transmissions. Itcan further be applied using alternative Quality of Service ob-jectives and constraints including energy efficiency and fairness.We consider network settings with multiple channels, multiplesinks, and stringent reliability constraints for data collectingflows. We compare the results to those achieved by the onlyscalable reliability-aware TDMA scheduling algorithm to ourknowledge, SchedEx, which conducts scheduling only. By makingrouting part of the problem and by introducing the conceptof source-aware routing, we achieve latency improvements forall topologies, with a notable average improvement of up to31percent.

• 344.
Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för data- och systemvetenskap.
Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för informations- och kommunikationssystem. Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för informations- och kommunikationssystem.
End-to-End Reliability-aware Scheduling for Wireless Sensor Networks2016Inngår i: IEEE Transactions on Industrial Informatics, ISSN 1551-3203, E-ISSN 1941-0050, Vol. 12, nr 2, s. 758-767Artikkel i tidsskrift (Fagfellevurdert)

Wireless Sensor Networks (WSN) are gaining popularity as a flexible and economical alternative to field-bus installations for monitoring and control applications. For missioncritical applications, communication networks must provide endto- end reliability guarantees, posing substantial challenges for WSN. Reliability can be improved by redundancy, and is often addressed on the MAC layer by re-submission of lost packets, usually applying slotted scheduling. Recently, researchers have proposed a strategy to optimally improve the reliability of a given schedule by repeating the most rewarding slots in a schedule incrementally until a deadline. This Incrementer can be used with most scheduling algorithms but has scalability issues which narrows its usability to offline calculations of schedules, for networks that are rather static. In this paper, we introduce SchedEx, a generic heuristic scheduling algorithm extension which guarantees a user-defined end-to-end reliability. SchedEx produces competitive schedules to the existing approach, and it does that consistently more than an order of magnitude faster. The harsher the end-to-end reliability demand of the network, the better SchedEx performs compared to the Incrementer. We further show that SchedEx has a more evenly distributed improvement impact on the scheduling algorithms, whereas the Incrementer favors schedules created by certain scheduling algorithms.

• 345.
Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för data- och systemvetenskap.
Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för informations- och kommunikationssystem. Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för informations- och kommunikationssystem.
QoS Assessment for Mission-critical Wireless Sensor Network Applications2013Inngår i: Proceedings - Conference on Local Computer Networks, LCN / [ed] Matthias Wählisch, IEEE Xplore , 2013, s. 663-666Konferansepaper (Fagfellevurdert)

Wireless sensor networks (WSN) must ensure worst-case end-to-end delay and reliability guarantees for mission-critical applications.TDMA-based scheduling offers delay guarantees, thus it is used in industrial monitoring and automation. We propose to evolve pairs of TDMA schedule and routing-tree in a cross-layer in order to fulfill multiple conflicting QoS requirements,exemplified by latency and reliability.The genetic algorithm we utilize can be used as an analytical tool for both the feasibility and expected QoS in production. Near-optimal cross-layer solutions are found within seconds and can be directly enforced into the network.

• 346.
Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för data- och systemvetenskap.
Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för informations- och kommunikationssystem. Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för informations- och kommunikationssystem.
QoS-Aware Cross-layer Configuration for Industrial Wireless Sensor Networks2016Inngår i: IEEE Transactions on Industrial Informatics, ISSN 1551-3203, E-ISSN 1941-0050, Vol. 12, nr 5, s. 1679-1691, artikkel-id 7485858Artikkel i tidsskrift (Fagfellevurdert)

In many applications of Industrial Sensor Networks, stringentreliability and maximum delay constraints paired with priority demands ona sensor-basis are present. These QoS requirements pose tough challenges forIndustrial Wireless Sensor Networks that are deployed to an ever largerextent due to their flexibility and extendibility.In this paper, we introduce an integrated cross-layer framework, SchedEx-GA, spanning MAC layer and networklayer. SchedEx-GA attempts to identify a network configuration that fulfills all application-specific process requirements over a topology including the sensorpublish rates, maximum acceptable delay, service differentiation, and eventtransport reliabilities. The network configuration comprisesthe decision for routing, as well as scheduling.

For many of the evaluatedtopologies it is not possible to find a valid configuration due to the physicalconditions of the environment. We therefore introduce a converging algorithm on top of the frameworkwhich configures a given topology by additional sink positioning in order tobuild a backbone with the gateway that guaranteesthe application specific constraints.The results show that, in order to guarantee a high end-to-end reliability of 99.999% for all flows in a network containing emergency, control loop, andmonitoring traffic, a backbone with multiple sinks is often required for thetested topologies. Additional features, such as multi-channel utilization andaggregation, though, can substantially reduce the demand for required sinks.In its present version, the framework is used for centralized control, butwith the potential to be extended for de-centralized control in future work.

• 347.
Poznan University, Poland.
Poznan University, Poland. University of Lisbon, Portugal. University of Malta, Malta. Institute de Telecomunicacôes and Politecico de Leiria, Portugal. Holografika, Budapest, Hungary. Institute de Telecomunicacôes and Politecico de Leiria, Portugal. University of Lisbon, Portugal. University of Cagliari, Italy. Institute de Telecomunicacôes and Politecico de Leiria, Portugal. Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för informationssystem och -teknologi. University of Lisbon, Portugal. Poznan university, Poland.
Emerging Imaging Technologies: Trends and Challenges2018Inngår i: 3D Visual Content Creation, Coding and Delivery / [ed] Assunção, Pedro Amado, Gotchev, Atanas, Cham: Springer, 2018, s. 5-39Kapittel i bok, del av antologi (Fagfellevurdert)
• 348.
Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för informationsteknologi och medier.
Cold molecules in pulsed optical lattices2005Inngår i: Progress in Quantum Electronics, ISSN 0079-6727, E-ISSN 1873-1627, Vol. 29, nr 1, s. 1-58Artikkel, forskningsoversikt (Fagfellevurdert)

We review recent theoretical studies on the dynamics of molecules in pulsed optical lattices. These lattices are periodic potential wells formed by the interaction between two counter propagating far-off resonant optical fields and the molecules. We show that the molecules can be manipulated in both constant velocity and accelerating lattices for a number of applications. We first study a molecular optical mirror through the reflections of molecules by a stationary optical lattice and show that the reflectivity can be significantly improved by optimizing the pulse duration. When reflection occurs from a moving lattice, we show that molecules can brought to rest when the lattice velocity is half the molecular velocity, demonstrating a new and efficient method for creating slow cold molecules. We further describe a microlinear accelerator for molecules produced by an accelerating optical lattice, which is achieved by frequency chirping one of the two optical fields. The molecules trapped by the potential wells of the lattice are accelerated to high velocities (10-100km/s) over micron-size distance within nanosecond time scales. When the lattice is decelerated, the trapped molecules can be slowed to zero velocity, offering an alternate method for producing slow cold molecules. Molecules that are not trapped in the accelerating lattice can be temporarily localized around a characteristic velocity,. which is uniquely dependent on the mass-to-polarizability ratio. We show that this feature can be used for a new form of time-of-flight mass spectrometry for chemical analysis of a mixture.

• 349.
University of Science and Technology of China.
University of Science and Technology of China. Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Institutionen för informationsteknologi och medier. University of Science and Technology of China. University of Science and Technology of China.
Spectroscopic analysis of LiKGdF5 : Er3+, Sm3+ single crystal2006Inngår i: Journal of Alloys and Compounds, ISSN 0925-8388, E-ISSN 1873-4669, Vol. 424, nr 1-2, s. 334-337Artikkel i tidsskrift (Fagfellevurdert)

Low temperature photoluminescence spectra were measured under the selective excitation to the energy levels of Gd3+,Er3+ and Sm3+, respectively. Corresponding transitions were assigned with the help of fluorescence decay measurements. By assuming that the rare earth ion is in C-2v symmetry instead of the actual C-2, crystal field calculations were carried out based on the deduced experimental energy level data of Er3+ and Sm3+. The theoretical result is in good agreement with the experimental data.

• 350.
Mittuniversitetet, Fakulteten för naturvetenskap, teknik och medier, Avdelningen för elektronikkonstruktion.
Design and verification of a USB 3.0 readout system for Timepix3 hybrid pixel detectors2018Independent thesis Advanced level (degree of Master (Two Years)), 10 poäng / 15 hpOppgave

This thesis describes the design, implementation, and verification of a USB 3.0 readout system for Timepix3 detectors. Timepix3 is a hybrid pixel detector consisting of a 256x256 pixel matrix with a 55 μm pitch and a timing resolution of 1.56ns. It allows to measure energy and time simultaneously utilising an event-driven data stream with a maximum data rate of up to 5.12 Gb/s or up to 85 million hits per second. Our aim is to implement a readout system that allows to add processing algorithms into the firmware, reducing the amount of data and the post-processing time. USB 3.0 was selected as an interface, because it provides a sufficient data rate and is present on all modern computers. Furthermore, the selected Opal Kelly XEM6310 development board provides a framework handling the communication between the FPGA and the host computer, FPGA components, and an API.

We implemented a hardware adapter board in collaboration with the University of Glasgow connecting the development board to the detector chip board converting the detector’s output signals from SLVS to LVDS signals. Moreover, we implemented FPGA firmware consisting of a detector interface, USB interface, and a core including a processing interface. A multi-platform desktop library was implemented in C/C++ using Qt, which is used to configure the readout system and handles high speed data streaming. Data analysis and verification is conducted using custom build Python scripts.

Simulations of the firmware showed the expected behaviour. The firmware and library were verified by configuring the detector, reading back the configuration, and measurements with an Americium source. An equalisation and a global and per-pixel energy calibration have been done successfully. Moreover, the system has been used to create and correct an X-ray image. Furthermore, the USB 3.0 data streaming performance was evaluated and it could be shown that the system can sustain a stream of around 380 MB/s.

The proposed readout system has been implemented and was verified in simulation and experiments with X-ray radiation. USB 3.0 data streaming performed better than anticipated reaching higher speeds as stated by Opal Kelly. Furthermore, the firmware and the library function as intended. The hardware adapter requires some changes to accommodate higher data speeds and the data chan- nels have to be moved to different pins to allow synchronisation to an external clock.

45678910 301 - 350 of 1597
Referera
Referensformat
• apa
• ieee
• modern-language-association-8th-edition
• vancouver
• Annet format
Fler format
Språk
• de-DE
• en-GB
• en-US
• fi-FI
• nn-NO
• nn-NB
• sv-SE
• Annet språk
Fler språk
Utmatningsformat
• html
• text
• asciidoc
• rtf