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  • 301. Bompard, E.
    et al.
    Correia, P.
    Gross, G.
    Amelin, M.
    KTH, Tidigare Institutioner.
    A Comparative Analysis of Congestion Management Schemes under a Unified Framework2002Ingår i: IEEE Power Engineering Review, ISSN 0272-1724, E-ISSN 1558-1705, Vol. 22, s. 59-60Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The restructuring of the electricity industry has spawned the introduction of new independent grid operators or IGOs, typically called transmission system operators (TSO), independent system operator (ISO) or regional transmission organizations (RTO), in various parts of the world. An important task of an IGO is congestion management (CM) and pricing. This activity has significant economic implications on every market participant in the IGO’s region. The paper briefly reviews the congestion management schemes and the associated pricing mechanism used by the IGO’s in five representative schemes. These were selected to Illustrate the various CM approaches in use: England and Wales, Norway, Sweden, PJM and Califomia. We develop a unified framework for the mathematical representation of the market dispatch and redispatch problems that the IGO must solve in CM in these various jurisdictions. We use this unified framework to develop meaningful metrics to compare the various CM approaches so as to assess their efficiency and the effectiveness of the market signals provided to the market participants. We compare, using a small test system, side by side, the performance of these schemes.

  • 302. Bompard, E.
    et al.
    Correia, P.
    Gross, G.
    Amelin, Mikael
    KTH, Tidigare Institutioner.
    Congestion-management schemes: A comparative analysis under a unified framework2003Ingår i: IEEE Transactions on Power Systems, ISSN 0885-8950, E-ISSN 1558-0679, Vol. 18, nr 1, s. 346-352Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The restructuring of the electricity industry has spawned the introduction of new independent grid operators (IGOs), typically called transmission system operators (TSOs); independent system operator (ISOs); or regional transmission organizations (RTOs), in various parts of the world. An important task of an IGO is congestion management (CM) and pricing. This activity has significant economic implications on every. market participant in the IGO's region. The paper briefly reviews the CM schemes and the associated pricing mechanism used by the IGOs in five representative schemes. These were selected to illustrate the various CM approaches in use: England and Wales, Norway, Sweden, PJM, and California. We develop a unified framework for the mathematical representation of the market dispatch and redispatch problems that the IGO must solve in CM in these various jurisdictions. We use this unified framework to develop meaningful metrics to compare the various CM approaches so as to assess their efficiency and the effectiveness of the market signals provided to the market participants. We compare, using a small test system, side by side, the performance of these schemes.

  • 303.
    Bonnaud, Etienne L.
    et al.
    KTH, Skolan för teknikvetenskap (SCI), Hållfasthetslära (Inst.). Infineon Technologies Sweden AB, Sweden .
    Gudmundson, Peter
    KTH, Skolan för teknikvetenskap (SCI), Hållfasthetslära (Inst.).
    Influence of component position on lead-free solder interconnections during drop test2005Konferensbidrag (Refereegranskat)
    Abstract [en]

    When subjected to drop test, interconnections between components and test board experience high stresses mainly due to differential bending. Using analytical and numerical modal analysis, bending moments have here been calculated and shown to strongly depend on the location on the test board; the highest value not being found at the centre, as usually stated. In parallel, experiments to determine visco-plastic material properties at high strain rates (∼1s-1) for lead-free solder (SnAgCu) have been performed and used in drop test simulations. Inelastic strains calculated at different locations confirm results from the modal analyses and give a first insight into the development of a drop test failure criterion.

  • 304.
    Borkar, Amol
    et al.
    Georgia Institute of Technology.
    Hayes, Monson
    Georgia Institute of Technology.
    Smith, Mark T.
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Kommunikationssystem, CoS.
    A New Multi-Camera Approach For Lane Departure Warning2011Ingår i: ACIVS 2011: Proceedings of Acivs 2011, 2011, s. 58-69Konferensbidrag (Refereegranskat)
    Abstract [en]

    In this paper, we present a new multi camera approach to Lane Departure Warning (LDW). Upon acquisition, the captured images are transformed to a bird's-eye view using a modified perspective removal transformation. Then, camera calibration is used to accurately determine the position of the two cameras relative to a reference point. Lane detection is performed on the front and rear camera images which are combined using data fusion. Finally, the distance between the vehicle and adjacent lane boundaries is determined allowing to perform LDW. The proposed system was tested on real world driving videos and shows good results when compared to ground truth.

  • 305.
    Borkar, Amol
    et al.
    Georgia Institute of Technology.
    Hayes, Monson
    Georgia Institute of Technology.
    Smith, Mark T.
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Kommunikationssystem, CoS.
    A Non Overlapping Camera Network: Calibration and Application Towards Lane Departure Warning2011Ingår i: IPCV 2011: Proceedings of the 15th International Conference on Image Processing, Computer Vision, and Pattern Recognition, 2011Konferensbidrag (Refereegranskat)
    Abstract [en]

    In this paper, we present a new multi camera approach toLane DepartureWarning (LDW). First, a perspective removaltransformation is applied to the camera captured images toconvert them into bird’s-eye view images. Then, the positionof the two cameras relative to a reference point is accuratelydetermined using a new calibration technique. Lane detectionis performed on the front and rear camera images who resultsare combined using data fusion. Finally, LDW is implementedby determining the distance between the vehicle andadjacent lane boundaries. The proposed system was tested onreal world driving videos and shows good results when comparedto ground truth.

  • 306. Borkar, Amol
    et al.
    Hayes, Monson
    Smith, Mark T.
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Kommunikationssystem, CoS.
    A Novel Lane Detection System With Efficient Ground Truth Generation2012Ingår i: IEEE transactions on intelligent transportation systems (Print), ISSN 1524-9050, E-ISSN 1558-0016, Vol. 13, nr 1, s. 365-374Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    A new night-time lane detection system and its accompanying framework are presented in this paper. The accompanying framework consists of an automated ground truth process and systematic storage of captured videos that will be used for training and testing. The proposed Advanced Lane Detector 2.0 (ALD 2.0) is an improvement over the ALD 1.0 or Layered Approach with integration of pixel remapping, outlier removal, and prediction with tracking. Additionally, a novel procedure to generate the ground truth data for lane marker locations is also proposed. The procedure consists of an original process called time slicing, which provides the user with unique visualization of the captured video and enables quick generation of ground truth information. Finally, the setup and implementation of a database hosting lane detection videos and standardized data sets for testing are also described. The ALD 2.0 is evaluated by means of the user-created annotations accompanying the videos. Finally, the planned improvements and remaining work are addressed.

  • 307.
    Borkar, Amol
    et al.
    Georgia Institute of Technology.
    Hayes, Monson
    Georgia Institute of Technology.
    Smith, Mark T
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Kommunikationssystem, CoS.
    Advanced Lane Detection Using Elliptical Lane Marker Grouping and Cascaded Templates2010Ingår i: ACIVS 2010: Proceedings of ACIVS 2010, 2010Konferensbidrag (Refereegranskat)
  • 308.
    Borkar, Amol
    et al.
    Georgia Institute of Technology.
    Hayes, Monson
    Georgia Institute of Technology.
    Smith, Mark T
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Kommunikationssystem, CoS.
    An Efficient Method to Generate Ground Truth For Evaluating Lane Detection Systems2010Ingår i: 2010 IEEE INTERNATIONAL CONFERENCE ON ACOUSTICS, SPEECH, AND SIGNAL PROCESSING, 2010, s. 1090-1093Konferensbidrag (Refereegranskat)
    Abstract [en]

    In this document, a new and efficient method to specify the ground truth locations of lane markers is presented. The method comprises of a novel process called Time-Slicing that provided the user with a unique visualization of the video. Coupled with automation via spline interpolation, the quick generation of necessary ground truth information is achieved. Videos recorded from a vehicle while driving on local city roads and highways are marked with ground truth information for use in testing. The performance of a variety of lane detection systems is compared to the ground truth and the error is computed for each system. Finally, quantitative analysis shows that the reference lane detection system presented in [1] produces the most accurate lane detections which is depicted by the smallest error.

  • 309.
    Borkar, Amol
    et al.
    Georgia Institute of Technology.
    Hayes, Monson
    Georgia Institute of Technology.
    Smith, Mark T.
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Kommunikationssystem, CoS.
    Detecting Lane Markers in Complex Environments Using a Monocular Camera2011Ingår i: SPPRA 2011: Proceedings of the Eighth IASTED International Conference on Signal Processing, Pattern Recognition, and Applications, 2011Konferensbidrag (Refereegranskat)
  • 310.
    Borkar, Amol
    et al.
    Georgia Institute of Technology.
    Hayes, Monson
    Georgia Institute of Technology.
    Smith, Mark T.
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Kommunikationssystem, CoS.
    Lane Detection Using Constraints of Parallel Lines2011Ingår i: ICCE 2011: Proceedings of the 29th IEEE International Conference on Consumer Electronics, 2011Konferensbidrag (Refereegranskat)
  • 311.
    Bormann, Dierk
    et al.
    KTH, Skolan för elektro- och systemteknik (EES), Elektroteknisk teori och konstruktion.
    Tavakoli, Hanif
    KTH, Skolan för elektro- och systemteknik (EES), Elektroteknisk teori och konstruktion.
    Reluctance Network Treatment of Skin and Proximity Effects in Multi-Conductor Transmission Lines2012Ingår i: IEEE transactions on magnetics, ISSN 0018-9464, E-ISSN 1941-0069, Vol. 48, nr 2, s. 735-738Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    A novel method is developed to easily compute the complex series impedance matrix of amulti-conductor transmissionline in a wide frequency range. It is based on a network of complex reluctances describing flux paths around the conductors. The network parameters are derived from the geometry of the conductor-insulator arrangement and from its material parameters. The method is best suited for situations where the typical gap width between conductors is much smaller than their thicknesses, where it provides an accurate treatment of both skin and proximity effects. Especially the proximity effect is hard to treat by other means in that limit. The method is demonstrated for an idealized example geometry, where its accuracy is verified with harmonic FEM field calculations.

  • 312.
    Bourchas, Konstantinos
    KTH, Skolan för elektro- och systemteknik (EES), Elektrisk energiomvandling.
    Manufacturing Effects on Iron Losses in Electrical Machines2015Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [sv]

    I detta examensarbete studeras hur de magnetiska egenskaperna hos SiFe-plat paverkas

    av skarning och svetsning. Permeabilitet och jarnforlustdensitet undersoks eftersom de

    ar kritiska variabler for elektriska maskiners prestanda. De magnetiska matningarna

    genomfordes pa en Epstein ram med en odesfrekvens pa 50, 100 och 200 Hz, enligt

    IEC 404-2. E ekterna av mekanisk skarning med giljotin samt skarning med ber- och

    CO2-laser studerades. Inverkan av olika berlaserinstallningar undersoktes ocksa genom

    att variera gastrycket, skarhastigheten samt frekvensen och e ekten av laserstralen.

    For att oka skare ekten inkluderades Epsteinremsor med ytterligare 1, 2 och 3 langsgaende

    skarsnitt. Det visas att mekanisk skarning har en mindre paverkan pa de magnetiska

    egenskaperna hos materialet an vad laserskarning har. Matningar pa plat med 1.8% Si

    visar att da prov med tre extra langsgaende giljotinklipp anvands kan permeabiliteten

    reduceras med upp till 63% och jarnforlusterna kan oka med upp till 35%. Motsvarande

    resultat for laserskurna platar visar en permeabilitetsreduktion pa upp till 65% och

    en jarnforlustokning pa upp till 65%. Ur studien av de tva studerade skarprocesserna

    framkommer aven att tunnare plat paverkas mindre negativt an tjockare plat. Ett antal

    olika installningar har provats for att utreda hur olika parametrar paverkar e ekterna

    av laserskarning. Studien indikerar att skarning med hog e ekt och hog hastighet ger

    den minsta paverkan pa materialets magnetiska egenskaper. Vilket aven har en positiv

    inverkan pa produktiviteten vid laserskarning.

    Epsteinprover har aven utforts for att undersoka vilka e ekter som introduceras da

    SiFe-plat svetsas. Provstyckena bestod av remsor med en, tre, fem och 10 svetspunkter.

    Experimenten visar en jarnforlustokning med upp till 50% samt en permeabilitetsreduktion

    upp till 62% da platarna svetsats samman tva och tva.

    En modell for att studera e ekterna av de forandrade materialegenskaperna vid skarning

    pa en induktionsmotor utvecklas och implementeras i en FEM-baserad mjukvara. Resultaten

    tyder pa en jarnforlustokning med 30% da skare ekten orsakad av giljotin beaktas.

    Vid simulering av laserskuren plat kan denna okning vara sa stor som 50%. Det framkommer

    aven att laserskarningen kan reducera e ektfaktorn sa mycket som 2.6%.

  • 313. Bratman, V. L.
    et al.
    Bandurkin, I. V.
    Fedotov, A. E.
    Kalynov, Y. K.
    Makhalov, Petr B.
    KTH, Skolan för elektro- och systemteknik (EES), Mikro- och nanosystemteknik. Russian Academy of Sciences, Russian Federation.
    Manuilov, V. N.
    Osharin, I. V.
    Savilov, A. V.
    Low-Voltage gyrotron for DNP applications: Project and features2017Ingår i: 2017 42nd International Conference on Infrared, Millimeter, and Terahertz Waves (IRMMW-THz), IEEE Computer Society, 2017, artikel-id 8067061Konferensbidrag (Refereegranskat)
    Abstract [en]

    A possibility of gyrotron operation at a very low voltage, 1.5-2 kV, is considered in the context of dynamic nuclear polarization (DNP) application. Simulations predict that a low-voltage device has some specific but useful features like efficiency operation at high axial modes and capability of wide-band frequency tuning.

  • 314. Bratman, V. L.
    et al.
    Fedotov, A. E.
    Makhalov, Petr B.
    KTH, Skolan för elektro- och systemteknik (EES), Mikro- och nanosystemteknik. Institute of Applied Physics of the RAS, Nizhny Novgorod, Russian Federation.
    Manuilov, V. N.
    Non-relativistic hollow electron beam formation for mm-wave BWO2017Ingår i: 10th International Workshop 2017 “Strong Microwaves and Terahertz Waves: Sources and Applications”, EDP Sciences , 2017, Vol. 149, artikel-id 04038Konferensbidrag (Refereegranskat)
  • 315. Brecher, C.
    et al.
    Kehne, Sebastian
    KTH.
    Epple, A.
    Primary operating reserve by means of regenerative industrial plants2019Ingår i: ZWF Zeitschrift fuer Wirtschaftlichen Fabrikbetrieb, Vol. 114, nr 1-2, s. 11-15Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The publication shows in a simulation how an emergency generating unit with uninterruptible power supply can be used to provide primary control for the grid and thus its electricity costs could be reduced. Furthermore, the use case shows exemplarily on how also consumers with recovery capabilities can be integrated in the control market. By adding a conventional emergency generating unit it is possible to fulfill the prescribed minimum holding period of 15 minutes. In contrast to other approaches the model of the electricity market does not have to be changed which increases the acceptance of this approach.

  • 316.
    Bresin, R.
    et al.
    KTH, Tidigare Institutioner (före 2005), Tal, musik och hörsel.
    Friberg, Anders
    KTH, Tidigare Institutioner (före 2005), Tal, musik och hörsel.
    Emotional expression in music performance: synthesis and decoding1998Ingår i: TMH-QPSR, Vol. 39, nr 4, s. 085-094Artikel i tidskrift (Övrigt vetenskapligt)
  • 317.
    Bresin, Roberto
    et al.
    KTH, Skolan för datavetenskap och kommunikation (CSC), Medieteknik och interaktionsdesign, MID.
    Elblaus, Ludvig
    KTH, Skolan för datavetenskap och kommunikation (CSC), Medieteknik och interaktionsdesign, MID.
    Frid, Emma
    KTH, Skolan för datavetenskap och kommunikation (CSC), Medieteknik och interaktionsdesign, MID.
    Favero, Federico
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE).
    Annersten, Lars
    Musikverket.
    Berner, David
    Musikverket.
    Morreale, Fabio
    Queen Mary University of London.
    SOUND FOREST/LJUDSKOGEN: A LARGE-SCALE STRING-BASED INTERACTIVE MUSICAL INSTRUMENT2016Ingår i: Sound and Music Computing 2016, SMC Sound&Music Computing NETWORK , 2016, s. 79-84Konferensbidrag (Refereegranskat)
    Abstract [en]

     In this paper we present a string-based, interactive, largescale installation for a new museum dedicated to performing arts, Scenkonstmuseet, which will be inaugurated in 2017 in Stockholm, Sweden. The installation will occupy an entire room that measures 10x5 meters. We aim to create a digital musical instrument (DMI) that facilitates intuitive musical interaction, thereby enabling visitors to quickly start creating music either alone or together. The interface should be able to serve as a pedagogical tool; visitors should be able to learn about concepts related to music and music making by interacting with the DMI. Since the lifespan of the installation will be approximately five years, one main concern is to create an experience that will encourage visitors to return to the museum for continued instrument exploration. In other words, the DMI should be designed to facilitate long-term engagement. Finally, an important aspect in the design of the installation is that the DMI should be accessible and provide a rich experience for all museum visitors, regardless of age or abilities.

  • 318.
    Bresin, Roberto
    et al.
    KTH, Tidigare Institutioner (före 2005), Tal, musik och hörsel. KTH, Tidigare Institutioner (före 2005), Talöverföring och musikakustik.
    Friberg, Anders
    KTH, Tidigare Institutioner (före 2005), Tal, musik och hörsel.
    A multimedia environment for interactive music performance1997Ingår i: Proceedings of KANSEI - The Technology of Emotion, AIMI International Workshop, 1997, s. 64-67Konferensbidrag (Refereegranskat)
  • 319.
    Briggner, Viktor
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik, Industriell ekologi.
    Grahn, Pontus
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik, Industriell ekologi.
    Johansson, Linus
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Hållbar utveckling, miljövetenskap och teknik, Industriell ekologi.
    Centralized Versus Distributed State Estimation for Hybrid AC/DC Grid2016Självständigt arbete på avancerad nivå (masterexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [en]

    State estimation enables for values throughout a power transmission grid to be known with a higher level of certainty. New technologies for bulk power transmission and power grid measuring enables for new possibilities in the energy sector and it is required that state estimation algorithms are developed to adapt to these new technologies. This project aims to develop a state estimator (SE) that is modified for hybrid AC/HVDC grids with voltage source converters (VSC) and phasor measurement units (PMU). Two different sets of architectures are tested. The centralized architecture where one common SE is implemented for both AC and DC grids or the distributed where a separate SE for every grid is used. The method used for the SE is the weighted least square (WLS) method. The SE will be developed based on the power grid model ’The CIGRE B4 DC Grid Test System’, designed by the International Council on Large Electric Systems (CIGRE) as a benchmark system. The SE is subject to four different scenarios in order to evaluate the quality of the SE, benefits of added phasor measurements and choice of architecture for the SE. The results of the tests show that the developed SE improves the accuracy of state values on the DC grid. However, regarding the AC state values of the converters the results of the test are ambiguous. Furthermore the distributed architecture offered slightly less accurate AC values than the centralized. The addition of PMU measurements improved the error of the estimated values. 

  • 320.
    Brodén, Daniel
    et al.
    KTH, Skolan för elektro- och systemteknik (EES), Industriella informations- och styrsystem.
    Sandels, Claes
    KTH, Skolan för elektro- och systemteknik (EES), Industriella informations- och styrsystem.
    Nordström, Lars
    KTH, Skolan för elektro- och systemteknik (EES), Industriella informations- och styrsystem.
    Assessment of Congestion Management Potential in Distribution Networks using Demand-Response and Battery Energy Storage2015Ingår i: Innovative Smart Grid Technologies Conference (ISGT), 2015 IEEE Power & Energy Society, IEEE conference proceedings, 2015Konferensbidrag (Refereegranskat)
    Abstract [en]

    The integration of large shares of renewable energy sources in distribution grids runs the risk of outpacing the capacity of the network. Thus, high investment costs are expected at distribution system level to expand the existing grid to manage, among other challenges, anticipated congestion. This paper involves a study of the technical feasibility of using an ancillary service toolbox including day- and hour-ahead demand-response and battery energy storage as an alternative to grid expansion. The ancillary service toolbox is applied on radial distribution grids having large shares of renewable generation, controllable loads and power export capability to the overlaying power grid. The toolbox is simulated for a real use case presenting results on required demand-response participants and operation of flexibility resources for different congestion scenarios. The study concludes that the ancillary service solution is technically feasible for the use case, which may imply network investment deferral for distribution system operators.

  • 321. Brostrom, Elin
    et al.
    Alvehag, Karin
    KTH, Skolan för elektro- och systemteknik (EES), Elektriska energisystem.
    Söder, Lennart
    KTH, Skolan för elektro- och systemteknik (EES), Elektriska energisystem.
    Calculation of Residential Interruption Costs caused by Adverse Weather using Monte Carlo Methods2008Konferensbidrag (Refereegranskat)
    Abstract [en]

    The main contribution of this paper is a residential interruption cost model that aims to capture households? inconvenience due to power outages caused by adverse weather. Commonly, the customer interruption cost is modelled to be a function of the outage duration. However, other factors also affect the interruption cost. For example, the cost for a household increases if public services also are affected by the outage. The number of public services that a household cannot use is often correlated to the total number of customers affected by the outage. This relationship is explored in the proposed cost model in order to consider the impact of widespread and long-lasting outages caused by, for example, adverse weather. An adverse weather model gives wind and ice loads. These loads in combination with a vulnerability model for components in a transmission system and a restoration time model give the outage duration. In a case study, the impact of adverse weather on a meshed test system with residential customers is studied using Monte Carlo simulations. It is concluded that more surveys investigating the increased costs for households due to long-lasting and widespread outages are needed.

  • 322. Brostrom, Elin
    et al.
    Söder, Lennart
    KTH, Skolan för elektro- och systemteknik (EES), Elektriska energisystem.
    ON TRANSMISSION RESTORATION EVALUATION AFTER ICE STORMS USING MONTE CARLO TECHNIQUES2006Ingår i: CRIS 2006 in Alexandria, USA, 2006Konferensbidrag (Refereegranskat)
  • 323.
    Broström, Elin
    et al.
    KTH, Skolan för elektro- och systemteknik (EES), Elektriska energisystem.
    Ahlberg, Jesper
    KTH, Skolan för elektro- och systemteknik (EES), Elektriska energisystem.
    Söder, Lennart
    KTH, Skolan för elektro- och systemteknik (EES), Elektriska energisystem.
    Modelling of ice storms and their impact applied to a part of the Swedish Transmission network2007Ingår i: 2007 IEEE LAUSANNE POWERTECH, VOLS 1-5, NEW YORK: IEEE , 2007, s. 1593-1598Konferensbidrag (Refereegranskat)
    Abstract [en]

    In this paper a technique of modelling severe weather for power system reliability calculations is developed. The model is based on geographically moving winds and precipitation and is suitable for transmission network. A scenario represents a weather situation with given parameters. Besides the weather model a stochastic vulnerability model for the components is required for each scenario that connects the risk of failure to the weather situation. In order to mitigate severe consequences of future ice storms in an efficient way it is essential to be able to estimate the consequences based on assumptions of the technical system and the severity of possible storms. It is assumed that the probability of a failure due to a given weather depends on load functions for wind and ice together with the component vulnerability model which is based on the design of the components. The wind load is direct and the ice load is given by a known ice accretion model. Conclusions about the reliability of the studied lines under ice storms are presented as well as a graph of the critical conditions for the studied lines with ice thickness on the x-axis and gust wind on the y-axis. The numerical examples show the impact of different weather situations on a part of the Swedish Transmission network using data both from real weather situations in Sweden and the weather model.

  • 324.
    Broström, Elin
    et al.
    KTH, Skolan för elektro- och systemteknik (EES), Elektriska energisystem.
    Söder, Lennart
    KTH, Skolan för elektro- och systemteknik (EES), Elektriska energisystem.
    Ice Storm Impact on Power System Reliability2007Ingår i: 12 th International Workshop on Atmospheric Icing on Structures (IWAIS 2007), Yokohama, Japan, 2007Konferensbidrag (Refereegranskat)
    Abstract [en]

    Ice storms are freezing rain that coats everything in ice, often in combination with heavy wind. The aim of the methods developed in this paper is to estimate the risk of failure due to ice storms. This includes a severe weather model, a new method for choosing weather parameters and a component vulnerability model. The weather model is based on how a low pressure behaves and consists of functions that describe the wind and precipitation parts of the weather. An ice accretion model is used to estimate the ice loads. The method for choosing weather parameters is useful for Monte Carlo simulations where the effects of many different weather situations are studied. In the stochastic component vulnerability model the failure rates are based on how an increased ice load influences the critical wind. Swedish weather conditions and transmission components are used in the case study and the loads and their impact are estimated for many different weather situations.

  • 325.
    Broström, Elin
    et al.
    KTH, Skolan för elektro- och systemteknik (EES), Elektriska energisystem.
    Söder, Lennart
    KTH, Skolan för elektro- och systemteknik (EES), Elektriska energisystem.
    Modelling of Ice Storms for Power Transmission Reliability Calculations2005Ingår i: Proceedings 15th Power Systems Computation Conference PSCC2005, Liège, Belgium: PSCC , 2005Konferensbidrag (Refereegranskat)
    Abstract [en]

    This paper describes a new technique of modelling adverse weather for power system reliability calculations. The reliability calculation is based on a Monte-Carlo technique where each scenario represents a certain weather situation with certain parameters. For each scenario a model of the adverse weather is needed and in this paper a model based on geographically moving winds and ice storms is developed. The benefit of this is that it is possible to estimatethe time difference between mean times to failure indifferent lines, not only the outage risk. For each scenario a weather impact model is also required, where the risk of transmission outage is connected to the weather situation.The here-developed model connects the direct wind impact with the integrating impact from the ice storm. The developed method is applied to a numerical example.

  • 326.
    Brunsell, Per. R.
    et al.
    KTH, Tidigare Institutioner, Alfvénlaboratoriet.
    Malmberg, Jenny-Ann
    KTH, Tidigare Institutioner, Alfvénlaboratoriet.
    Yadikin, Dimitry
    KTH, Tidigare Institutioner, Alfvénlaboratoriet.
    Cecconello, Marco
    KTH, Tidigare Institutioner, Alfvénlaboratoriet.
    Resistive wall modes in the EXTRAP T2R reversed-field pinch2003Ingår i: Physics of Plasmas, ISSN 1070-664X, E-ISSN 1089-7674, Vol. 10, s. 3823-Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Resistive wall modes (RWM) in the reversed field pinch are studied and a detailed comparison of experimental growth rates and linear magnetohydrodynamic (MHD) theory is made. RWM growth rates are experimentally measured in the thin shell device EXTRAP T2R [P. R. Brunsell , Plasma Phys. Controlled Fusion 43, 1 (2001)]. Linear MHD calculations of RWM growth rates are based on experimental equilibria. Experimental and linear MHD RWM growth rate dependency on the equilibrium profiles is investigated experimentally by varying the pinch parameter Theta=B-theta(a)/<B-phi> in the range Theta=1.5-1.8. Quantitative agreement between experimental and linear MHD growth rates is seen. The dominating RWMs are the internal on-axis modes (having the same helicity as the central equilibrium field). At high Theta, external nonresonant modes are also observed. For internal modes experimental growth rates decrease with Theta while for external modes, growth rates increase with Theta. The effect of RWMs on the reversed-field pinch plasma performance is discussed.

  • 327.
    Brunsell, Per
    et al.
    KTH, Tidigare Institutioner, Alfvénlaboratoriet.
    Yadikin, Dimitry
    KTH, Tidigare Institutioner, Alfvénlaboratoriet.
    Gregoratto, D.
    Paccagnella, R.
    Bolzonella, T.
    Cavinato, M.
    Cecconello, Marco
    KTH, Tidigare Institutioner, Alfvénlaboratoriet.
    Drake, James Robert
    KTH, Tidigare Institutioner, Alfvénlaboratoriet.
    Luchetta, A.
    Manduchi, G.
    Marchiori, G.
    Marrelli, L.
    Martin, P.
    Masiello, A.
    Milani, F.
    Ortolani, S.
    Spizzo, G.
    Zanca, P.
    Feedback Stabilization of Multiple Resistive Wall Modes2004Ingår i: Physical Review Letters, ISSN 0031-9007, E-ISSN 1079-7114, Vol. 93, nr 22, s. 225001-Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Active feedback stabilization of multiple independent resistive wall modes is experimentally demonstrated in a reversed-field pinch plasma. A reproducible simultaneous suppression of several nonresonant resistive wall modes is achieved. Coupling of different modes due to the limited number of the feedback coils is observed in agreement with theory. The feedback stabilization of nonresonant RWMs also has an effect on tearing modes that are resonant in the central plasma, leading to a significant prolongation of the discharge pulse.

  • 328.
    Brunsell, Per
    et al.
    KTH, Skolan för elektro- och systemteknik (EES), Centra, Alfvénlaboratoriet.
    Yadikin, Dmitriy
    KTH, Skolan för elektro- och systemteknik (EES), Centra, Alfvénlaboratoriet.
    Cecconello, Marco
    KTH, Skolan för elektro- och systemteknik (EES), Centra, Alfvénlaboratoriet.
    Drake, James Robert
    KTH, Skolan för elektro- och systemteknik (EES), Centra, Alfvénlaboratoriet.
    Marchiori, Giuseppe
    Feedback stabilization of resistive wall modes in a reversed-field pinch2005Ingår i: Physics of Plasmas, ISSN 1070-664X, E-ISSN 1089-7674, Vol. 12, nr 9, s. 092508-Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    An array of saddle coils having Nc =16 equally spaced positions along the toroidal direction has been installed for feedback control of resistive wall modes (RWMs) on the EXTRAP T2R reversed-field pinch [P. R. Brunsell, H. Bergsaker, M. Cecconello, Plasma Phys. Controlled Fusion 43, 1457 (2001)]. Using feedback, multiple nonresonant RWMs are simultaneously suppressed for three to four wall times. Feedback stabilization of RWMs results in a significant prolongation of the discharge duration. This is linked to a better sustainment of the plasma and tearing mode toroidal rotation with feedback. Due to the limited number of coils in the toroidal direction, pairs of modes with toroidal mode numbers n, n′ that fulfill the condition ∫n- n′ ∫ = Nc are coupled by the feedback action from the discrete coil array. With only one unstable mode in a pair of coupled modes, the suppression of the unstable mode is successful. If two modes are unstable in a coupled pair, two possibilities exist: partial suppression of both modes or, alternatively, complete stabilization of one target mode while the other is left unstable.

  • 329.
    Brännlund, Håkan
    KTH, Skolan för elektro- och systemteknik (EES), Elkraftteknik.
    Network Programming Applied too Operation Planning of Hydrothermal Power Systems1986Doktorsavhandling, monografi (Övrigt vetenskapligt)
    Abstract [en]

    The objective of the project was to develop models and methods suitable for computer implementation. In particular, this work has been devoted to generation scheduling of a power system with a sizeable amount. of hydro energy. Optimal operation planning of hydrothermal power systems aims at minimizing incurred production costs while supplying customer de­mand. The planning horizon may vary from one day to several years and the associated planning problems are categorized as short term, seasonal and long term operation planning. The topic of this thesis is short term operation planning.

    In this planning, it is necessary to use detailed models of the different parts of the power system. These include models of cas­caded reservoirs in a multi-river system as we11 as a representa­tion of the nonlinear generating characteristics of the hydro plants.

    he thermal generating units are modelled using linear production cost curves and by recognizing various technical constraints asso­ciated with the operation of these plants.

    Effects on the optimal operating strategy caused by interregional transmission capacity limitations are also accounted for by the model. These constraints are modelled to main1y affect the hydro plant operation.

  • 330.
    Bu, Junfu
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap, Tillämpad processmetallurgi.
    Jönsson, Pär G.
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap, Tillämpad processmetallurgi.
    Zhao, Zhe
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap, Tillämpad processmetallurgi. Shanghai Institute of Technology, China.
    Ionic conductivity of dense BaZr(0.5)Ce(0.3)Ln(0.2)O(3-delta) (Ln = Y, Sm, Gd, Dy) electrolytes2014Ingår i: Journal of Power Sources, ISSN 0378-7753, E-ISSN 1873-2755, Vol. 272, s. 786-793Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    BaZr(0.5)Ce(0.3)Ln(0.2)O(3-delta) (BZCLn532, Ln = Y, Sm, Gd, Dy) based electrolytes were successfully synthesized by a cost-effective solid-state reactive sintering (SSRS) method while using 1.0 wt.% NiO as a sintering aid. Dense pellets of BZCLn532 compounds can be prepared at sintering temperatures of 1600 degrees C (BZCY532) and 1400 degrees C (BZCS532, BZCG532 and BZCD532). The conductivities of the dense BZCLn532 ceramics were tested in dry and wet air at temperatures of 700 degrees C-200 degrees C. On the basis of the obtained results, it could be concluded that the BZCY532-based electrolyte show promise for use as oxygen-ion conductors and proton conductors in intermediate temperature solid oxide fuel cells (ITSOFCs).

  • 331.
    Buendia, Ruben
    et al.
    University of Borås, Sweden.
    bogonez-franco, Paco
    Technical University of Catalonia.
    Nescolarde, Lexa
    Technical University of Catalonia.
    Seoane, Fernando
    KTH, Skolan för teknik och hälsa (STH), Medicinska sensorer, signaler och system (MSSS).
    Influence of electrode mismatch on Cole parameter estimation from Total Right Side Electrical Bioimpedance Spectroscopy measurements2012Ingår i: Medical Engineering and Physics, ISSN 1350-4533, E-ISSN 1873-4030, Vol. 34, nr 7, s. 1024-1028Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Applications based on measurements of Electrical Bioimpedance (EBI) spectroscopy analysis, like assessment of body composition, have proliferated in the past years. Currently Body Composition Assessment (BCA) based in Bioimpedance Spectroscopy (BIS) analysis relays on an accurate estimation of the Cole parameters R-0 and R-infinity. A recent study by Bogonez-Franco et al. has proposed electrode mismatch as source of remarkable artefacts in BIS measurements. Using Total Right Side BIS measurements from the aforementioned study, this work has focused on the influence of electrode mismatch on the estimation of R-0 and R-infinity using the Non-Linear Least Square curve fitting technique on the modulus of the impedance. The results show that electrode mismatch on the voltage sensing electrodes produces an overestimation of the impedance spectrum leading to a wrong estimation of the parameters R-0 and R-infinity, and consequently obtaining values around 4% larger that the values obtained from BIS without electrode mismatch. The specific key factors behind electrode mismatch or its influence on the analysis of single and spectroscopy measurements have not been investigated yet, no compensation or correction technique is available to overcome the deviation produced on the EBI measurement. Since textile-enabled EBI applications using dry textrodes, i.e. textile electrodes with dry skin-electrode interfaces and potentially large values of electrode polarization impedance are more prone to produce electrode mismatch, the lack of a correction or compensation technique might hinder the proliferation of textile-enabled EBI applications for personalized healthcare monitoring.

  • 332.
    Buendia, Ruben
    et al.
    KTH, Skolan för teknik och hälsa (STH), Medicinska sensorer, signaler och system (MSSS).
    Gil-Pita, Roberto
    Department of Theory of the Signal and Communications.
    Seoane, Fernando
    KTH, Skolan för teknik och hälsa (STH), Medicinska sensorer, signaler och system (MSSS).
    Cole Parameter Estimation from the Modulus of the Electrical Bioimpeadance for Assessment of Body Composition: A Full Spectroscopy Approach2011Ingår i: Journal of Electrical Bioimpedance, ISSN 1891-5469, E-ISSN 1891-5469, Vol. 2, s. 72-78Artikel i tidskrift (Refereegranskat)
    Abstract [en]

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

  • 333.
    Bueno, Fermin
    et al.
    KTH, Tidigare Institutioner, Elektroniksystemkonstruktion.
    Öberg, Johnny
    Kumar, Anshul
    Torkelsson, Mats
    Ericsson AB.
    High-Level Synthesis of a 1 Mbps Direct-Sequence Spread-Spectrum RAKE Receiver1996Ingår i: Workshop on Synthesis And System Integration, 1996, s. 170-177Konferensbidrag (Refereegranskat)
  • 334.
    Buono, Benedetto
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Integrerade komponenter och kretsar.
    Simulation and Characterization of Silicon Carbide Power Bipolar Junction Transistors2012Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    The superior characteristics of silicon carbide, compared with silicon, have suggested considering this material for the next generation of power semiconductor devices. Among the different power switches, the bipolar junction transistor (BJT) can provide a very low forward voltage drop, a high current capability and a fast switching speed. However, in order to compete on the market, it is crucial to a have high current gain and a breakdown voltage close to ideal. Moreover, the absence of conductivity modulation and long-term stability has to be solved.

    In this thesis, these topics are investigated comparing simulations and measurements. Initially, an efficient etched JTE has been simulated and fabricated. In agreement with the simulations, the fabricated diodes exhibit the highest BV of around 4.3 kV when a two-zone JTE is implemented. Furthermore, the simulations and measurements demonstrate a good agreement between the electric field distribution inside the device and the optical luminescence measured at breakdown.

    Additionally, an accurate model to simulate the forward characteristics of 4H-SiC BJTs is presented. In order to validate the model, the simulated current gains are compared with measurements at different temperatures and different base-emitter geometries. Moreover, the simulations and measurements of the on-resistance are compared at different base currents and different temperatures. This comparison, coupled with a detailed analysis of the carrier concentration inside the BJT, indicates that internal forward biasing of the base-collector junction limits the BJT to operate at high current density and low forward voltage drop simultaneously. In agreement with the measurements, a design with a highly-doped extrinsic base is proposed to alleviate this problem.

    In addition to the static characteristics, the comparison of measured and simulated switching waveforms demonstrates that the SiC BJT can provide fast switching speed when it acts as a unipolar device. This is crucial to have low power losses during transient.

    Finally, the long-term stability is investigated. It is observed that the electrical stress of the base-emitter diode produces current gain degradation; however, the degradation mechanisms are still unclear. In fact, the analysis of the measured Gummel plot suggests that the reduction of the carrier lifetime in the base-emitter region might be only one of the causes of this degradation. In addition, the current gain degradation due to ionizing radiation is investigated comparing the simulations and measurements. The simulations suggest that the creation of positive charge in the passivation layer can increase the base current; this increase is also observed in the electrical measurements.

  • 335.
    Buono, Benedetto
    et al.
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Integrerade komponenter och kretsar.
    Ghandi, Reza
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Integrerade komponenter och kretsar.
    Domeij, Martin
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Integrerade komponenter och kretsar.
    Malm, B. Gunnar
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Integrerade komponenter och kretsar.
    Zetterling, Carl-Mikael
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Integrerade komponenter och kretsar.
    Östling, Mikael
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Integrerade komponenter och kretsar.
    Current Gain Degradation in 4H-SiC Power BJTs2011Ingår i: Materials Science Forum, ISSN 0255-5476, E-ISSN 1662-9752, Vol. 679-680, s. 702-705Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    SiC airs are very attractive for high power application, but long term stability is still problematic and it could prohibit commercial production of these devices. The aim of this paper is to investigate the current gain degradation in BJTs with no significant degradation of the on-resistance. Electrical measurements and simulations have been used to characterize the behavior of the BJT during the stress test. Current gain degradation occurs, the gain drops from 58 before stress to 43 after 40 hours, and, moreover, the knee current shows fluctuations in its value during the first 20 hours. Current gain degradation has been attributed to increased interface traps or reduced lifetime in the base-emitter region or small stacking faults in the base-emitter region, while fluctuations of the knee current might be due to stacking faults in the collector region.

  • 336.
    Buono, Benedetto
    et al.
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Integrerade komponenter och kretsar.
    Ghandi, Reza
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Integrerade komponenter och kretsar.
    Domeij, Martin
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Integrerade komponenter och kretsar.
    Malm, B. Gunnar
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Integrerade komponenter och kretsar.
    Zetterling, Carl-Mikael
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Integrerade komponenter och kretsar.
    Östling, Mikael
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Integrerade komponenter och kretsar.
    Temperature Modeling and Characterization of the Current Gain in 4H-SiC Power BJTs2010Ingår i: Materials Science Forum, ISSN 0255-5476, E-ISSN 1662-9752, Vol. 645-648, s. 1061-1064Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The current gain of 4H-SiC BJTs has been modeled using interface traps between SIC and SiO2 to describe surface recombination, by a positive temperature dependence of the carrier lifetime in the base region and by bandgap narrowing in the emitter region. The interface traps have been modeled by one single level at 1 eV above the valence band, with capture cross section of 1 x 10(-15) cm(2) and concentration of 2 x 10(12) cm(-2). The temperature behavior of SiC BJTs has been simulated and the results have been compared with measurements. An analysis of the carrier concentration has been performed in order to describe the mechanisms for fall-off of the current gain at high collector current. At room temperature high injection in the base and forward biasing of the base-collector junction occur simultaneously causing an abrupt drop of the current gain. At higher temperatures high injection in the base is alleviated by the higher ionization degree of the aluminum dopants, and then forward biasing of the base-collector junction is the only acting mechanism for the current gain fall-off at high collector current. This mechanism and the negative temperature dependence of the carrier mobility can also explain the reduction of the knee current for gain fall-off with increasing temperature. Simulations with different emitter widths have been also performed and analyzed to characterize the emitter size effect. Higher current density caused by reducing the emitter width introduces higher carrier recombination in the emitter region, leading to a reduction of the current gain.

  • 337.
    Buono, Benedetto
    et al.
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Integrerade komponenter och kretsar.
    Lee, Hyung-Seok
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Integrerade komponenter och kretsar.
    Domeij, Martin
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Integrerade komponenter och kretsar.
    Zetterling, Carl -Mikael
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Integrerade komponenter och kretsar.
    Östling, Mikael
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Integrerade komponenter och kretsar.
    Simulations of Open Emitter Breakdown Voltage in SiC BJTs with non Implanted JTE2009Ingår i: Materials Science Forum, ISSN 0255-5476, E-ISSN 1662-9752, Vol. 615-617, s. 841-844Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Ion implantation for selective doping of SiC is problematic due to damage generation during the process and low activation of dopants. In SiC bipolar junction transistor (BJT) the junction termination extension (JTE) can be formed without ion implantation using instead a controlled etching into the epitaxial base. This etched JTE is advantageous because it eliminates ion implantation induced damage and the need for high temperature annealing. However, the dose, which is controlled by the etched base thickness and doping concentration, plays a crucial role. In order to find the optimum parameters, device simulations of different etched base thicknesses have been performed using the software Sentaurus Device. A surface passivation layer consisting of silicon dioxide, considering interface traps and fixed trapped charge, has been included in the analysis by simulations. Moreover a comparison with measured data for fabricated SiC BJTs has been performed.

  • 338.
    Butt, Bilal
    KTH, Skolan för elektro- och systemteknik (EES), Elektroteknisk teori och konstruktion.
    Electric and electromagnetic modelling for railway traction system applications2015Självständigt arbete på avancerad nivå (yrkesexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [sv]

    Tågindustrin är ett område som är under löpande utveckling. Allt eftersom tekniken rör sig

    framåt blir även den kravställning kunderna ställer på leverantörer. Ett tågdrivsystem består

    idag utav ett stort antal komponenter där leverantörer av dessa drivsystem måste förlita sig på

    underleverantörer för att uppnå en viss prestanda.

    Detta examensarbete visar med tre olika fältstudier hur man med hjälp av mjukvara baserad

    på finita elementmetoden kan användas för implementering på ett tågdrivsystem. Ett sådant

    verktyg är COMSOL Multiphysics.

    Den första fältstudien visar hur man kan modellera elektromagnetiska fält producerade av en

    induktor som används i filter-sammanhang och för att se den resulterande upphettningen

    förorsakad av de producerade magnetfälten.

    Den andra fältstudien beskriver hur mana kan förutspå den resulterande upphettningen

    beroende utav ojämnheter i en skarv där två statorkablar i en motor löds ihop. Tre olika

    nivåer på ojämnheter undersöktes och resultaten visar att ur ett termiskt perspektiv har nivån

    på ojämnheterna ingen påverkan.

    Den tredje och sista fältstudien presenterar en undersökning rörande vilken slags induktor

    som skall användas för ett filter i ett specifikt system. Tre olika förslag ges där alla har sina

    för- och nackdelar. Utifrån dessa resultat är en rekommendation given baserat på vad en

    systemdesigner måste ta hänsyn till när ett aktivt val måste göras.

    Slutsatsen av examensarbetet är att modellering utav elektriska och elektromagnetiska

    komponenter kan användas för att beräkna elektromagnetiska fält, bestämma induktans,

    skärmning samt högfrekvent beteende för induktorer samt upphettning pga induktion samt

    resistiv upphettning.

  • 339.
    Bylerius, Patrik
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Medicinteknik och hälsosystem, Hälsoinformatik och logistik.
    Positionering av tågvagn med hjälp av ett Kalmanfilter2019Självständigt arbete på grundnivå (högskoleexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [sv]

    Positionering av tågvagnar är en viktig del av järnvägen. Dagligen används Sveriges järnvägar av 1000-tals tåg, vilket medför en säkerhetsrisk om inte det finns teknik för att upptäcka tågvagnstapp.

    Projektet undersökte om det med hjälp av ett Kalmanfilter på en Raspberry Pi med variablerna latitud och longitud kunde positionera en tågvagn i realtid. Projektet undersökte även om Kalmanfiltret som programmerades kunde ersätta en GPS där täckning inte fanns i området.

    En prototyp framställdes och utvärderades genom att ett Kalmanfilter programmerades och implementerades på en enkortsdator tillsammans med en GPS-modul.

    Simuleringar av flera värden gjordes för att säkerställa de värden som uppkom. Prototypen visar att metoden fungerar inom den felmarginal järnvägen kräver för ett säkert system. Resultatet visar en avvikelse av den positionen som eftersöktes med Kalmanfiltret. Koordinaterna för latitud hade en differens med 0,9 m jämfört med det Kalmanfilter som programmerades. Longitud hade också en differens men med 0,001 m jämfört mot de värdena som GPS-modulen genererade.

  • 340. Cai, F.
    et al.
    Yu, J.
    He, Sailing
    KTH, Skolan för elektro- och systemteknik (EES), Elektroteknisk teori och konstruktion. KTH, Skolan för informations- och kommunikationsteknik (ICT), Centra, Zhejiang-KTH Joint Research Center of Photonics, JORCEP.
    Vectorial electric field Monte Caro simulations for focused laser beams (800 nm-2220 nm) in a biological sample2013Ingår i: Progress In Electromagnetics Research, ISSN 1070-4698, E-ISSN 1559-8985, Vol. 142, s. 667-681Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Here we develop a method that combines vectorial electric field Monte Carlo simulation with Huygens-Fresnel principle theory to determine the intensity distribution of a focused laser beam in a biological sample. The proper wavelengths for deep tissue imaging can be determined by utilizing our method. Furthermore, effects of anisotropic factor, scattering and absorption coeffcients on the focal spots are analyzed. Finally, the focal beams formed by objective lenses with different values of numerical aperture are also simulated to study the focal intensity in the biological sample.

  • 341.
    Cairo, Ignasi
    et al.
    IREC.
    Del Rosario, Gerard
    IREC.
    Dominguez, J.L.
    IREC.
    Vanfretti, Luigi
    KTH, Skolan för elektro- och systemteknik (EES), Elektriska energisystem.
    Al-Khatib, Iyad
    KTH, Skolan för elektro- och systemteknik (EES), Elektriska energisystem.
    Baudette, Maxime
    KTH, Skolan för elektro- och systemteknik (EES), Elektriska energisystem.
    Almas, M. Shoaib
    KTH, Skolan för elektro- och systemteknik (EES), Elektriska energisystem.
    Equipos para medidas precisas de fase en tension corriente para redes inteligentes2013Ingår i: Automatica e Instrumentación, ISSN 0213-3113, nr 451, s. 87-90Artikel i tidskrift (Övrig (populärvetenskap, debatt, mm))
  • 342. Camacho, Miguel
    et al.
    Mitchell-Thomas, Rhiannon C.
    Hibbins, Alastair P.
    Sambles, J. Roy
    Quevedo-Teruel, Oscar
    KTH, Skolan för elektro- och systemteknik (EES), Elektroteknisk teori och konstruktion.
    Designer surface plasmon dispersion on a one-dimensional periodic slot metasurface with glide symmetry2017Ingår i: Optics Letters, ISSN 0146-9592, E-ISSN 1539-4794, Vol. 42, nr 17, s. 3375-3378Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    In this Letter, we explore the dispersion of spoof surface plasmons supported by a single-layer glide-symmetric structure. This structure consists of an infinitely long double-notched slot perforated in a metal layer. The presence of a degeneracy of the two lowest-order modes at the Brillouin zone boundary, which have non-zero group velocity is explained and experimentally demonstrated. Further, the dependence of the band structure when glide-symmetric configuration is broken is also explored.

  • 343.
    Campion, James
    et al.
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Mikro- och nanosystemteknik.
    Beuerle, Bernhard
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Mikro- och nanosystemteknik.
    Krivovitca, Aleksandr
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Mikro- och nanosystemteknik.
    Shah, Umer
    KTH, Skolan för elektro- och systemteknik (EES), Mikro- och nanosystemteknik.
    Oberhammer, Joachim
    KTH, Skolan för elektro- och systemteknik (EES), Mikro- och nanosystemteknik.
    Low-Loss Hollow and Silicon-Core Micromachined Waveguide Technologies Above 100 GHz2018Konferensbidrag (Övrigt vetenskapligt)
  • 344.
    Campion, James
    et al.
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Mikro- och nanosystemteknik.
    Glubokov, Oleksandr
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Mikro- och nanosystemteknik.
    Gomez-Torrent, Adrian
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Mikro- och nanosystemteknik.
    Krivovitca, Aleksandr
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Mikro- och nanosystemteknik.
    Shah, Umer
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Mikro- och nanosystemteknik.
    Bolander, Lars
    Ericsson Research.
    Li, Yinggang
    Ericsson Research.
    Oberhammer, Joachim
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Mikro- och nanosystemteknik.
    An Ultra Low-Loss Silicon-Micromachined Waveguide Filter for D-Band Telecommunication Applications2018Ingår i: 2018 IEEE/MTT-S International Microwave Symposium, IEEE, 2018, s. 583-586Konferensbidrag (Refereegranskat)
    Abstract [en]

    A very low-loss micromachined waveguide bandpassfilter for use in D-band (110–170GHz) telecommunication applicationsis presented. The 134–146GHz filter is implemented in a silicon micromachined technology which utilises a double H-plane split, resulting in significantly lower insertion loss than conventional micromachined waveguide devices. Custom split-blocks are designed and implemented to interface with the micromachined component. Compact micromachined E-plane bends connect the split-blocks and DUT. The measured insertion loss per unit length of the waveguide technology (0.008–0.016 dB/mm) is the lowest reported to date for any micromachined waveguide at D-band. The fabricated 6-pole filter, with a bandwidth of 11.8 GHz (8.4%), has a minimum insertion loss of 0.41 dB, averaging 0.5 dB across its 1 dB bandwidth, making it the lowest-loss D-band filter reported to date in any technology. Its return loss is better than 20 dB across 85% of the same bandwidth. The unloaded quality factor of a single cavity resonator implemented in this technology is estimated to be 1600.

  • 345.
    Campion, James
    et al.
    KTH, Skolan för elektro- och systemteknik (EES), Mikro- och nanosystemteknik.
    Shah, Umer
    KTH, Skolan för elektro- och systemteknik (EES), Mikro- och nanosystemteknik.
    Oberhammer, Joachim
    KTH, Skolan för elektro- och systemteknik (EES), Mikro- och nanosystemteknik.
    Elliptical alignment holes enabling accurate direct assembly of micro-chips to standard waveguide flanges at sub-THz frequencies2017Ingår i: 2017 IEEE MTT-S International Microwave Symposium (IMS), Institute of Electrical and Electronics Engineers (IEEE), 2017, s. 1262-1265, artikel-id 8058838Konferensbidrag (Refereegranskat)
    Abstract [en]

    Current waveguide flange standards do not allow for the accurate fitting of microchips, due to the large mechanical tolerances of the flange alignment pins and the brittle nature of Silicon, requiring greatly oversized alignment holes on the chip to fit worst-case fabrication tolerances, resulting in unacceptably large misalignment error for sub-THz frequencies. This paper presents, for the first time, a new method for directly aligning micromachined Silicon chips to standard, i.e. unmodified, waveguide flanges with alignment accuracy significantly better than the waveguide-flange fabrication tolerances, through the combination of a tightly-fitting circular and an elliptical alignment hole on the chip. A Monte Carlo analysis predicts the reduction of the mechanical assembly margin by a factor of 5.5 compared to conventional circular holes, reducing the potential chip misalignment from 46 μm to 8.5 μm for a probability of fitting of 99.5%. For experimental verification, micromachined waveguide chips using either conventional (oversized) circular or the proposed elliptical alignment holes were fabricated and measured. A reduction in the standard deviation of the reflection coefficient by a factor of up to 20 was experimentally observed from a total of 200 measurements with random chip placement, exceeding the expectations from the Monte Carlo analysis. To our knowledge, this paper presents the first solution for highly accurate assembly of micromachined waveguide chips to standard waveguide flanges, requiring no custom flanges or other tailor-made split blocks.

  • 346. Cantoni, M.
    et al.
    Jönsson, Ulf T.
    KTH, Skolan för teknikvetenskap (SCI), Matematik (Inst.), Optimeringslära och systemteori.
    Kao, C. -Y
    IQC robustness analysis for feedback interconnections of unstable distributed parameter systems2009Ingår i: Proceedings of the 48th IEEE Conference on Decision and Control, 2009 held jointly with the 2009 28th Chinese Control Conference. CDC/CCC 2009, IEEE , 2009, s. 1124-1130Konferensbidrag (Refereegranskat)
    Abstract [en]

    In recent work the authors combined integral-quadratic-constraint (IQC) based analysis with ν-gap metric based analysis to study the robustness of feedback interconnections of possibly unstable rational transfer functions. This is extended here to the case of irrational transfer functions without pure delays. Specifically, we restrict attention to the sub-algebra of Callier-Desoer class transfer functions that have a limit at infinity.

  • 347. Cantoni, Michael
    et al.
    Jönsson, Ulf T.
    KTH, Skolan för teknikvetenskap (SCI), Matematik (Inst.), Optimeringslära och systemteori.
    Kao, Chung-Yao
    Robustness Analysis for Feedback Interconnections of Distributed Systems via Integral Quadratic Constraints2012Ingår i: IEEE Transactions on Automatic Control, ISSN 0018-9286, E-ISSN 1558-2523, Vol. 57, nr 2, s. 302-317Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    A framework is established for directly accommodating feedback interconnections of unstable distributed-parameter transfer functions in robust stability analysis via integral quadratic constraints (IQCs). This involves transfer function homotopies that are continuous in a nu-gap metric sense. As such, the development includes the extension of nu-gap metric concepts to an irrational setting and the study of uncertainty-set connectedness in these terms. The main IQC based robust stability result is established for constantly-proper transfer functions in the Callier-Desoer algebra; i.e. finitely many unstable poles and a constant limit at infinity. Problems of structured robust stability analysis and robust performance analysis are considered to illustrate use of the main result. Several numerical examples are also presented. These include stability analysis of an autonomous system with uncertain time-delay and a closed-loop control system, accounting for both the gain and phase characteristics of the distributed-parameter uncertainty associated with the nominal rational plant model used for controller synthesis.

  • 348.
    Carlborg, Carl Fredrik
    et al.
    KTH, Skolan för elektro- och systemteknik (EES), Mikrosystemteknik (Bytt namn 20121201).
    Haraldsson, Tommy
    KTH, Skolan för elektro- och systemteknik (EES), Mikrosystemteknik (Bytt namn 20121201).
    Stemme, Göran
    KTH, Skolan för elektro- och systemteknik (EES), Mikrosystemteknik (Bytt namn 20121201).
    Wijngaart, Wouter van der
    KTH, Skolan för elektro- och systemteknik (EES), Mikrosystemteknik (Bytt namn 20121201).
    RELIABLE BATCH MANUFACTURING OF MINIATURIZED VERTICAL VIAS IN SOFT POLYMER REPLICA MOLDING2007Ingår i: 11th International Conference on Miniaturized Systems for Chemistry and Life Sciences (microTAS 2007), 2007, s. 527-529Konferensbidrag (Refereegranskat)
    Abstract [en]

    We introduce and have successfully tested an uncomplicated polydimethylsiloxane (PDMS) compatible method for batch manufacturing vertical microfluidic interconnects via a surface inhibition of cationic photopolymerization. The yield of the maskless method is 100%. Moreover, the method enhances bond strength with subsequently laminated polymer layers.

  • 349.
    Carlborg, Carl Fredrik
    et al.
    KTH, Skolan för elektro- och systemteknik (EES), Mikrosystemteknik (Bytt namn 20121201).
    Haraldsson, Tommy
    KTH, Skolan för elektro- och systemteknik (EES), Mikrosystemteknik (Bytt namn 20121201).
    Öberg, Kim
    KTH, Skolan för kemivetenskap (CHE), Fiber- och polymerteknologi.
    Malkoch, Michael
    KTH, Skolan för kemivetenskap (CHE), Fiber- och polymerteknologi.
    van der Wijngaart, Wouter
    KTH, Skolan för elektro- och systemteknik (EES), Mikrosystemteknik (Bytt namn 20121201).
    BEYOND PDMS:: OFF-STOCHIOMETRY THIOL-ENE BASED SOFT LITHOGRAPHY FOR RAPID PROTOTYPING OF MICROFLUIDIC DEVICES2010Ingår i: 14th International Conference on Miniaturized Systems for Chemistry and Life Sciences (micro TAS 2010), 2010, s. 70-72Konferensbidrag (Refereegranskat)
    Abstract [en]

    We present an easy to use, rapid fabrication platform for microfluidic systems, based on micro-molding of novel thiolene based polymer formulations. The novel fabrication platform addresses major drawbacks of PDMS by allowing large freedom in material and surface properties, including: (photo)patterning of stable surface modifications, bonding without plasma treatment, rapid UV or thermal curing, variable E-modulus, minimized leaching of uncured components [1] and suppressed non-specific binding of biomolecules [2]. This process is potentially suited for both rapid prototyping in the laboratory and medium-scale commercial production, bridging the “development gap”.

  • 350.
    Carlborg, Carl Fredrik
    et al.
    KTH, Skolan för elektro- och systemteknik (EES), Mikrosystemteknik (Bytt namn 20121201).
    Saharil, Farizah
    KTH, Skolan för elektro- och systemteknik (EES), Mikrosystemteknik (Bytt namn 20121201).
    Haraldsson, Tommy
    KTH, Skolan för elektro- och systemteknik (EES), Mikrosystemteknik (Bytt namn 20121201).
    Wijngaart, Wouter van der
    KTH, Skolan för elektro- och systemteknik (EES), Mikrosystemteknik (Bytt namn 20121201).
    LOW TEMPERATURE “CLICK” WAFER BONDING OF OFF-STOICHIOMETRY THIOL-ENE (OSTE) POLYMERS TO SILICON2011Ingår i: 15th International Conference on Miniaturized Systems for Chemistry and Life Sciences (microTAS 2011), 2011, s. 1143-1145Konferensbidrag (Refereegranskat)
    Abstract [en]

    We present a low temperature (< 37°C) wafer-scale microfluidic batch packaging process using covalent, dry bonding of offstoichiometry thiol-ene polymers (OSTE), enabling rapid, bio-compatible integration of fluidics on wafer-scale in combination with excellent polymer properties.

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