People of ACM European Chapters - Veljko Pejovic

July 25, 2019

Can you briefly describe your own line of research and how you became interested in this area?

Over a little more than a decade, the smartphone has become the digital Swiss Army Knife—we have it with us at all times and use it for a wide range of applications. Unfortunately, all these applications compete for our attention, creating a cacophony of notifications that often interrupt us at inappropriate times, reducing our work efficiency and causing stress. In 2012, I joined the University of Birmingham, UK as a part of an interdisciplinary team, which, among other things, aimed to understand how machine learning and mobile sensing can be harnessed to model human interruptibility—so that information can be delivered via mobile devices at times when an intended recipient is likely to engage in the communication.

Later in my career, as an assistant professor at the University of Ljubljana, I dug deeper into the reasons for varying interruptibility and examined how a person's location, physical activity, collocation with other users, relationship to a person sending a message, and many other factors, impact her openness to incoming messages. At present, we are working on systems that rely on non-intrusive measurements of a user's physiological signals, such as breathing and heartbeat, in order to infer one's task engagement, and then schedule the incoming messages to minimize interruption. My team and I like to build stuff. Therefore, besides modeling human behavior, we actively investigate the most efficient means of realizing mobile systems, which includes research on resource-efficient mobile technologies, energy-efficient sensing, and similar mobile computing aspects.

In your area of research, what recent advance/emerging subfield will yield important advances in the years ahead?

Despite tremendous advances in mobile computing devices' hardware capabilities, as well as in the machine learning algorithms, our mobile devices don’t yet autonomously understand our needs. The lack of this understanding means that people become very much aware of and annoyed by all these ubiquitous devices grabbing our attention. In the future, I believe that successful ubiquitous computing devices will simply steer our attention, similar to what researcher Mark Weiser envisioned in a 1991 paper. The term we use for predicting and proactively addressing a mobile user's needs is “anticipatory mobile computing.” Advances in this field will require the collective efforts of many computing specialists: machine learning experts will need to create models of users' future behavior and how it changes after autonomous actions are taken; human-computer interaction experts will need to communicate these actions in the most appropriate way; and mobile systems experts will need to construct systems that respect the tight energy, processing, and storage constraints of mobile devices.

Will you tell us a little about the Bled ACM SIGCHI Chapter?

Established in 2019, the chapter is a very young chapter that aims to connect human-computer interaction researchers active in Slovenia and the surrounding regions, from northern Croatia to northeast Italy and beyond. Moving to the area just a few years ago, I was surprised to discover how active HCI research is here. What I find particularly astounding is that the region's research often transcends the traditional scientific article output and delivers prototypes, open source software, and spinoff companies.

Yet research efforts in the region remain rather fragmented, and one of the top priorities of our chapter is to provide a forum where individual groups can consolidate their efforts, potentially creating a front capable of running very large research projects and translating this research into high-impact practice. The first major step in this direction is the Human-Computer Interaction in Information Society (HCI-IS 2019) conference that we will organize this October. I’d like to invite all HCI researchers and practitioners—especially those active in southeastern and central Europe—to come and join us for the occasion! We named the chapter "Bled" after one of the most stunning lakes in the world, and this might be your opportunity to see it!

What advice would you offer a younger colleague just starting out in the field?

Communication is crucial for great research, and merely communicating via scientific publications is not enough. Discuss your work with as many people as possible and be ready to change your direction accordingly. Especially in areas such as HCI, if research is good, laypeople should understand the need for it and experts should appreciate its scientific value. Do not get attached to your ideas early on—be ready to question them, abandon them, move on. Finally, the most exciting research often lies at the boundaries between disciplines. There is so much you can learn from experts in other branches of computer science, or ever further, from electrical engineers, psychologists, or sociologists. Indeed, unhindered interdisciplinary exchange is one of the most valuable perks of academia. Enjoy it!


Veljko Pejovic is an assistant professor at the Faculty of Computer and Information Science, University of Ljubljana, Slovenia. With a broad interest in mobile and wireless computing, he has conducted research in computer networks, distributed systems, mobile sensing, machine learning, and the interaction of technology and society. His honors include co-authoring a Best Paper Nominee at UbiComp 2014 and co-authoring a Best Paper Award for the 2013 Data for Development (D4D) Challenge.

Pejovic is the Vice Chair of the Bled (Slovenia) ACM SIGCHI Chapter.