Step by step, the University of Klagenfurt is steadily expanding its activities in the new research area “Humans in the Digital Age”. The appointment of Elisabeth Oswald (University of Bristol) represents an important milestone in this endeavour. As an applied cryptographer, Elisabeth Oswald works at the interface between mathematics and computer science. In her research, she focuses especially on the cryptographic aspects of cybersecurity.

Rendering theory useful in a practical setting is one of the central aims of Elisabeth Oswald’s work. “I want to make things work in real life”, she succinctly summarises her engineering-mathematical approach. Her research focuses on applied cryptography. Aided by statistical methods, she strives to detect and shut down data leaks in various applications (such as the smart phone, cash dispensing machines, car keys, etc.). These kinds of devices offer numerous information channels, which can be exploited in the course of an attack. “In the long term, the aim is to develop a form of cryptography that minimises or tolerates leaks”, Elisabeth Oswald explains.

Those who believe that fully secure systems already exist are mistaken, according to the mathematician: “There is not a single device, as far as I am aware, that is immune to attack.”  Encryption technologies provide good services in many quarters, but ultimately, cryptography can only offer absolute security in theory. Often, tricks borrowed from the field of computer science are deployed in order to make systems less vulnerable in practice. “In addition, we need to address how best to test and evaluate cryptographic implementations”, Elisabeth Oswald goes on to say. She refers to an EU project (ERC Consolidator Grant) she is currently leading, which aims to achieve advances in this area.

Born in Wolfsberg, Elisabeth Oswald studied technical mathematics with a particular emphasis on information processing at Graz University of Technology. She completed her doctoral degree there in 2003. She has been working at the University of Bristol since 2006, and she recently held a professorship in applied cryptography there. In her view, the greatest advantage offered by the academic environment is the opportunity to work with young people: “It is a privilege to be allowed to accompany students on their path of knowledge acquisition and personal growth.”

Elisabeth Oswald transferred to the University of Klagenfurt in June 2019. The university will effect this appointment by means of opportunity hiring (direct appointments acc. to § 99a Universities Act). As such, Elisabeth Oswald is the first professor to be appointed to the newly established Digital Age Research Center (D^!ARC). Rector Oliver Vitouch: “The aim of D^!ARC, which was established on the 1^st of January 2019 as an interfaculty centre, is to explore the technological, economic, legal, societal, individual, and cultural aspects of the digital revolution. To do this, we aim to attract and connect the best and brightest, from the budding scientist to the acclaimed professor. The digital transformation will affect each and every one of us. Here, in Klagenfurt, we provide our students with the requisite knowledge to actively participate in shaping that change”.

Der Beitrag The University of Klagenfurt makes the first professorial appointment to the Digital Age Research Center (D!ARC): Elisabeth Oswald, who specializes in researching cybersecurity, arrives in Klagenfurt erschien zuerst auf University of Klagenfurt.

Source: AAU TEWI

While MRI, CT and x-ray already provide valuable insights into the interior of the body, the technology involving so-called magnetic particle imaging now promises new possibilities with high resolution, less acquisition time and no harmful radiation. In order to be able to draw conclusions about biological processes based on the observation of magnetic particles in a magnetic field, research has to rely on mathematics. Tram Thi Ngoc Nguyen is completing her doctoral thesis on this topic at the University of Klagenfurt.

“Those who are willing to work hard and have the patience to allow the field of mathematics to open up to them, are rewarded in the end: They gain profound knowledge of the beauty of this discipline”, Tram Thi Ngoc Nguyen tells us. She came to the University of Klagenfurt from Vietnam in order to pursue her doctoral studies here. Before this, she spent eight years working as a geophysicist in the industrial sector. She regards Klagenfurt as a location that is ideally suited to conducting research: “The city is very peaceful and surrounded by mountains and the lake, which offer a stunning backdrop. There is also less distraction here than elsewhere.” Asked to explain what defines the aesthetics of mathematics, she offers her thoughts on the matter: “One endeavours to get to the bottom of things, and is faced with clear proofs, which remove all ambiguity. For me, this clarity is beautiful.” When she first started her studies, she was primarily interested in chemistry and computer science. It took a while before she found her way into this special discipline.  Nonetheless, she enthusiastically encourages others to take this course, and adds: “Even if you believe that mathematics lies above your own intellectual capabilities: It is absolutely worthwhile to put in the effort. I still find mathematics quite demanding, even today, but I also find it very enjoyable.”

In line with this approach, she is currently working on her doctoral thesis with great intensity, with the aim of making a contribution to new medical imaging techniques. The so-called magnetic particle imaging (MPI), which will be deployed in future alongside other procedures such as CT, MRI or x-ray, looks set to offer new possibilities. MPI is a dynamic imaging modality for medical applications that has been recently introduced in 2005 by B. Gleich and J. Weizenecker. The technique involves introducing magnetic nanoparticles into the bloodstream of a patient and generating an image of particle concentration. This procedure is expected to permit very high resolution (less than 1 micrometre, which is better than MRI) and greater speed (just 0.1 second for acquisition time, also faster than MRI) when it comes to visualising the human blood flow. All that acts on the body from the outside is an oscillating magnetic field. The nanoparticles in the body subsequently behave according to the magnetic field causing the change in the particle magnetization, thus induces an electric current in a coil.  By measuring the induced voltage in multiple receive coils, it is possible to draw conclusions about the spatial concentration of the particles inside the body. Since the particles are distributed along the bloodstream of a patient, the particle concentration yields information on the blood flow.

Mathematics supports this process with the help of so-called “inverse problems”. These are used to trace the effect of a system (the measured voltage in the receive coils) back to an underlying cause (the particle concentration). The theoretical part of Tram Thi Ngoc Nguyen’s work is largely completed. What follows now is a series of experiments, which will mostly be conducted at a computer for the mathematical aspects. In the long term, Tram Thi Ngoc Nguyen hopes to remain in the world of academia once she has completed her doctoral studies, “as this offers great freedom to follow one’s individual interests.” Plenty of interesting questions remain, she believes, particularly in the case of inverse problems, which are extremely challenging or even unsolvable from today’s point of view.

Der Beitrag Mathematics supports new medical imaging techniques erschien zuerst auf University of Klagenfurt.

Source: AAU TEWI

Machines are already capable of many things. A certain set of sensors has already been fully developed. And yet, Harald Gietler, researcher at the Department of Smart Systems Technologies seeks to discover: “Who knows what kinds of sensors we will need in the future?” He is currently developing a new technology, which will allow machines to determine the location of other machines.

Harald Gietler specialises in electrical engineering. Using electromagnetic fields, for instance, he hopes to improve the localisation of autonomous systems, such as robots or drones. Explaining the mechanism involved, he tells us: “There’s a transmitter and a receiver. Between the two, an electromagnetic field is established, which helps the receiver to determine the location of the transmitter.”

This technology could be useful, for example, in production halls where several robots are actively deployed, or in the case of wireless charging platforms, which require drones to land as accurately as possible. When asked whether there are limits to using an electromagnetic field in this way, Gietler replies: “Yes, there are limits. However, within a range of just a few metres we can provide a position determination that is precise to the nearest centimetre. What counts is this: the closer, the better.”

Under the supervision of Hubert Zangl, professor at the Department of Smart Systems Technologies, Harald Gietler is working on this topic for his doctoral thesis. In the course of his scientific career, he recently had the opportunity to spend a semester abroad at the renowned ETH Zürich, where he focused on a different aspect of the functionality of this technology. Specifically, electromagnetic fields are subject to disturbance variables, which often take the form of conductive objects, usually made of metal. “In many cases, robots are also made of metal”, Harald Gietler points out. In order to be able to deliver correct results despite these disturbance variables, their effects must be taken into account in the mathematical model. For this, attention needs to be paid to both the respective metals and the design of the robots. Due to the intensive support received at ETH Zurich, Gietler and his supervising professor were able to achieve very good results within a very short time. After returning to Klagenfurt, he now wants to process these results further. What is more, he is already preparing for a further research period abroad.

It appears that Harald Gietler, who began his studies in Information and Communications Engineering after completing the secondary technical college in Klagenfurt and who is now about to complete his doctorate, is aiming straight for a scientific career. When asked, he elaborates: “Yes, research offers many advantages. One of them is freedom. Freedom to work on whatever interests you. And, to a large degree, freedom to do that wherever and whenever you want”. Harald Gietler also enjoys teaching. Whether his path will eventually lead him to a professorship, or whether he will be tempted by a job in industry, is still wide open. “At any rate, I’m not worried,” he explains. Thanks to his goal-oriented approach to work, there is certainly no need for concern.

A few words with … Harald Gietler

What would you be doing now, if you had not become a scientist?

I’ve never really thought about it. I’d probably be a freelancer.

Do your parents understand what it is you are working on?

Possibly not in every detail, but they certainly grasp the basics.

What is the first thing you do when you arrive at the office in the morning?

Chat with my colleagues over a cup of coffee.

Do you have proper holidays? Without thinking about your work?

Absolutely.

What makes you furious?

Injustice.

What calms you down?

Sports. It allows me to forget the worries of everyday life.

Who do you regard as the greatest scientist in history, and why?

I don’t think it’s possible to name a single person. Progress is based on the work of many. If I had to choose, I would mention James Clerk Maxwell, because his work has a significant influence on mine.

What embarrasses you?

My occasional impatience.

What are you afraid of?

Obtaining unsatisfactory results from experiments that have been planned far in advance.

What are you looking forward to?

My upcoming annual surfing trip to Portugal.

Download: Harald Gietler | aau/Müller

Der Beitrag Expanding the sensory skills of machines erschien zuerst auf University of Klagenfurt.

Source: AAU TEWI

In practical settings, ten minutes of flight time are generally not enough for most applications. A team comprised of researchers from the University of Klagenfurt (AAU) and NASA-JPL/California is working on ways to enable the autonomous flight of drones in several stages with intermittent charging phases. Christian Brommer, AAU doctoral student, has recently published the results of his research.

When Christian Brommer came to Klagenfurt from California, he brought a subtle, barely noticeable American accent with him. We met him to discuss his recent publication on the autonomous and long-duration flight of helicopter-drones, also known as rotorcraft UAS. It quickly became clear that the mission time of such small drones, roughly the size of a shoebox is even shorter than one might generally assume.

The origins of Brommer’s work can be traced back to the time he spent at NASA’s Jet Propulsion Laboratory (JPL) at the California Institute of Technology in Pasadena. The department of agricultural sciences and the Robotic Aerial Mobility Group located there are collaborating on a particular study case: Rotorcraft UAS equipped with multispectral cameras are deployed to patrol agricultural land by air. It is hoped that data collected in this way will allow biologists to determine the condition of the plants. To date, this task has been performed by stationary instruments, which have a limited reach, and light aircraft, which lead to significantly higher costs.

Helicopter-drones can offer an agile and cost-efficient alternative, though they have a disadvantage due to their size. Equipped with a battery the size of a typical smartphone, these helicopters can only fly for a few minutes at a time.

The goal the research team initially set itself was to allow this process to run autonomously. During the flight, the helicopter-drone should recognize when the battery is running low and return to a charging station in a timely manner. Having arrived there, the on-board computer transmits the recorded data to a basestation while the helicopter battery is automatically charged. Once recharged, the drone should be able to take off again. Using this mission plan, a plot of arable land can be accurately surveyed in several stages.

For this sequence to work smoothly, several challenges must be faced, as Christian Brommer explains: “We need sophisticated state-estimation algorithms that provide an accurate location of the helicopter to navigate and touch down precisely on the one square metre charging platform. Markings applied to the charging platform help us to achieve this. These are recognized by a camera and allow greater precision for the navigation required during the landing phase. Our algorithms for the state estimation combine data from several sensors to determine the best possible position of the helicopter. While the navigation of drones in laboratory environments and the aid of motion capture systems are already very accurate, once we are outdoors, numerous factors such as wind, changes in air pressure or lighting conditions that affect the sensors make it more difficult to estimate an accurate location. Especially because the usual GPS positioning only allows an accuracy of about five meters.

The results of the study were recently presented at the internationally renowned IROS conference (IEEE/RSJ International Conference on Intelligent Robots and Systems) and in the Journal of Field Robotics (JFR), in a special issue focusing on agricultural robotics. Having first met Stephan Weiss at NASA’s research centre in California several years ago, Christian Brommer has recently joined him in Klagenfurt, to pursue his doctoral degree here. Brommer grew up in Werne, a small town in the northwest of Germany and is the first one in his family who pursues his PhD. “But life in the countryside also laid strong foundations for my subsequent move into technology and I could always count on the support of my family”, he told us during the interview. He studied at the University of Applied Sciences in Dortmund and then went to JPL to complete his Master’s degree. The initial 6-month contract turned into three and a half years, which had a lasting effect on him: “At JPL you have the opportunity to work with the very best in each discipline. The intensive concentration of knowledge in one place gives you the feeling of having many more opportunities to choose from.” Stephan Weiss, professor at the Department of Smart Systems Technologies at the University of Klagenfurt is widely regarded as the driving force in the area of state estimation for unmanned aerial vehicles (UAV). As a member of Weiss’s research group, Christian Brommer is ideally placed to take his next steps in the world of science.

Christian Brommer, Danylo Malyuta, Daniel R. Hentzen, and Roland Brockers. Long-duration autonomy for small rotorcraft UAS including recharging. In Proc. IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS), 2018. https://ieeexplore.ieee.org/document/8594111

Danylo Malyuta, Christian Brommer, Daniel Hentzen, Thomas Stastny, Roland Siegwart and Roland Brockers. Long-Duration Fully Autonomous Operation of Rotorcraft UAS for Remote-Sensing Data Acquisition. Journal of Field Robotics (JFR) Special Issue on Agricultural Robotics. DOI:10.1002/rob.21898

Der Beitrag Enabling drones to fly long-durations autonomously erschien zuerst auf University of Klagenfurt.

Source: AAU TEWI