DTU Electrical Engineering in Pro! le 2010 DTU Electrical Engineering in Pro! le 2010 Editorial function: Bettina Bork & Kristian Stubkjær Photography: Birgitte Sundwall, Sonja Iskov, Lasse Rusborg, Colourbox, Lars Bahl, Peter Ho! mann, " orkild Amdi Christensen, Evert J. Friberg-Jensen, Lars Skaaning Cover: Electronics, photo Mikkel Adsbøll Reproduction and printing: Brande Bladet Design: Artcome DTU Electrical Engineering Technical University of Denmark Ørsteds Plads, building 349 DK-2800 Kgs. Lyngby www.elektro.dtu.dk E-mail: [email protected] ISBN: 978-87-92465-29-0 Contents Introduction ............................................................................................................................................................... 2 Facts and ! gures ................................................................................................................................................... 3 PhD projects .............................................................................................................................................................. 4 Awards, honours and appointments ....................................................................................................... 42 Public outreach ........................................................................................................................................................ 44 Advisory board ......................................................................................................................................................... 48 Management .............................................................................................................................................................. 48 Publications ................................................................................................................................................................. 48 Links .................................................................................................................................................................................. 48 1 DTU ELECTRICAL ENGINEERING IN PROFILE 2010 Introduction We are happy to present this pro! le magazine 2010 that re" ects our many research ! elds and activities. DTU Electrical Engineering is the central department at DTU within electrical engineering, within bio-medical engineering and within our new ! eld of playware. We experience an enormous interest in our activities from the world round us including many new students. # is is clearly emphasising the relevance of the activities for society: • # e health sector and the biomedical industry rely on our activities in hearing technology, ultrasound imaging and the increasing number of activities in a wide range of biomedical engineering and technologies for diagnosis of diseases • Activities in playware also address health issues and therapeutics via play as well as the well being of people of all ages. # e area supports the growth of a new industry • We engage in future electric energy systems including the intelligent grid which is crucial for Denmark to achieve 30 % renewable energy in 2020 • Our world leading activities on energy saving solutions in electric power systems, power electronics and automation and control are of importance to both industry and private households • Our expertise on antennas and microwaves is used in activities ranging from telecommunications and sensing to the new topic of body area networks • # e traditionally strong acoustics industry in Denmark is relying on our expertise and our candidates in the ! eld of electro-acoustics and building acoustics. We are delighted to be a very popular choice for the students of DTU which is re" ected in full uptake on our three bachelor programs. At the same time the number of students on our master programs has nearly tripled during the last couple of years. We strive to maintain high standards regarding the student training and have recently renewed our bachelor programs. Much of our project oriented training is in collaboration with industry. O$ en solutions derive from student projects, and our research projects ! nd their way into new products. We are happy that our students are in high demand. A considerable part of our research activities are linked to PhD projects. Currently we have about 70 PhD projects in the department; many are sponsored or conducted in collaboration with industry. We have chosen to concentrate this pro! le magazine on our PhD projects in stead of giving detailed descriptions of the activities in our sections. If you are interested in further details of our activities you are welcome to contact us. We hope you will enjoy reading this pro! le magazine. Professor Kristian Stubkjær Head of Department 2 DTU ELECTRICAL ENGINEERING IN PROFILE 2010 Facts and ! gures Income 2008 2009 Expenses 2008 2009 External funds 33,826 37,489 Salaries 62,921 77,127 Industrial/commercial 1,070 1,433 Operational costs 22,240 19,071 DTU funding 60,242 68,699 Total 85,161 96,198 Total 95,138 107,621 60,000 80,000 45,000 30,000 40,000 in 1000 DKK 15,000 in 1000 DKK 0 0 External funds Industrial/commercial DTU funding 2008 2009 2009 37,489 1,433 68,699 Salaries 62,921 77,127 2008 33,826 1,070 60,242 Operational costs 22,240 19,071 Total sta! * 2008 2009 Education 2008 2009 Faculty sta" 40 40 Graduated MScEE 79 80 Externally ! nanced 22 35 Graduated Bachelor EE 38 35 PhD students 45 68 Student f.t.e.*(value added) 414 370 Tech/Adm sta" 38 41 * f.t.e.=full time equivalent (årsværk) Total 143 184 * f.t.e.=full time equivalent (årsværk) 70 60 50 450 40 30 300 20 150 10 full time equivalent 0 0 Faculty sta! Externally PhD Tech/Adm Graduated Graduated Student "nanced students sta! MScEE Bachelor EE f.t.e.*(value added) 2009 40 35 68 41 2009 80 35 370 2008 40 20 45 38 2008 79 38 414 3 DTU ELECTRICAL ENGINEERING IN PROFILE 2010 ACOUSTIC TECHNOLOGY Head of group: Associate Professor Finn Jacobsen he research activities at Acoustic Technology may be divided into electro acoustics, physical acoustics, and architectural Tacoustics. In what follows a few examples of the group’s research activities from 2009 have been singled out. Some important acoustic transducers, e.g. loudspeakers, are inherently weakly nonlinear. If the nonlinearities are su% ciently well understood and the important parameters are known, the unwanted distortion can be removed using nonlinear control theory. Unfortunately, parameter dri$ is a serious problem with ordinary loudspeakers. Our research indicates that the problem of parameter dri$ is much less of an issue for the miniature loudspeakers in hearing aids, and there are reasons to expect that a nonlinear compensation technique can be successful. A remarkably simple and powerful stochastic model for predicting measurement uncertainties in reverberation rooms has been developed by our group. # e model takes account of the phenomenon known as “weak Anderson localization”, and has so far been used successful in predicting the uncertainty associated with the sound power emitted in a reverberation room, and the uncertainty associated with the " uctuations in potential energy density, kinetic energy density, and sound intensity. Statistical room acoustic models based on the concept of modal overlap in the frequency domain have been extremely successful for more than half a century, but similar considerations in the time domain have never led to convincing results. Our group, however, has developed a good model of the phenomenon based on the simple idea that not only does the re" ection density increase with time; the widths of the impulses are increased with each re" ection. PhD Projects Speaker’s comfort and increase of their voice level in lecture rooms Vocal health is a major concern among teachers and represents a signi! cant cost for the school authorities. The physical environment of the teaching room – not only the background noise – plays a very important role in determining the average voice power levels at which teachers speak. When designing the acoustics of a classroom, one has to predict quantitatively the vocal e" ort that the teachers will experience, and regulations regarding classroom acoustics should take account of the voice levels needed to speak in classrooms to improve the teacher’s vocal health. In this project a virtual auditory environment is used for determining the voice levels that teachers use in di" erent simulated classrooms under di" erent background noise conditions. Additional measurements are carried out in real classrooms during teaching activities. Physical measures of the classroom and of the sound ! eld are used to predict variations in the voice levels. To be completed: 2011 David Pelegrin Garcia 4 DTU ELECTRICAL ENGINEERING IN PROFILE 2010 Modeling structural acoustic properties of loudspeaker cabinets Modern loudspeaker systems are becoming increasingly complex. Consequently, the design engineers have to face the fact that unwanted structural acoustic problems may occur unexpectedly after a pre-production prototype has been manufactured and tested. Such problems are usually solved ad hoc at a late stage and may involve excessive costs to the modi! cation of production tools. Thus, prediction techniques are becoming more and more important. The objective of this project is to develop new techniques for predicting the structural acoustic properties and forced vibration response of loudspeaker cabinets of irregular geometry. More speci! cally, the goal is to