Event

Learning hard chart constraints for efficient context-free parsing by Brian Roark – Oregon Health & Science University

Abstract: In this talk, I’ll present some recent work in learning hard constraints for cells within a context-free parsing chart, to reduce parsing time. Each cell in the chart represents one of the O(n^2) substrings of the input string, and characteristics of each substring can be used to decide how much work to do in the associated chart cell. I’ll discuss finite-state models for tagging chart constraints on words, including methods for bounding the worst-case complexity of the parsing pipeline to quadratic or sub-quadratic in the length of the string. Empirical results will be presented for English and Chinese, achieved by constraining various high accuracy parsers.

Finally, I will present a generalization of these finite-state approaches that performs a quadratic number of classifications (one for each substring) to produce further (finer) constraints on the amount of processing within each cell. This latter approach has the nice property of being trained on maximum likelihood parses, rather than reference parses, making for a straightforward method for tuning parsing efficiency to new tasks and domains.

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Event details

  • When: 27th September 2011 13:00 - 14:00
  • Where: Cole 1.33
  • Series: CS Colloquia Series
  • Format: Colloquium

Is provenance logical? (James Cheney, University of Edinburgh)

Research on provenance in databases (or other settings) sometimes has an arbitrary flavor. Once we abandon the classical semantics of queries there is a large design space for alternative semantics that could provide some useful provenance information, but there is little guidance for how to explore this space or justify or compare different proposals. Topics from mathematical or philosophical logic could be used as a way of inspiring, justifying or comparing different approaches to provenance in databases. This talk will give a short tutorial on provenance in databases and present several topics in logic that may bear upon provenance techniques. These areas include nonclassical logics (e.g. relevance logic), algebraic logic (cylindric algebras), substructural logic (e.g. linear logic) and logics of knowledge, belief or causality.

Event details

  • When: 21st September 2011 13:00 - 14:00
  • Where: Cole 1.33a
  • Format: Seminar

Exploring semantics in situation identification using context lattices by Dr.Juan Ye

Pervasive systems must offer an open, extensible, and evolving portfolio of services which integrate sensor data from a diverse range of sources. The core challenge is to provide appropriate and consistent adaptive behaviours for these services in the face of huge volumes of sensor data exhibiting varying degrees of precision, accuracy and dynamism. Situation identification is an enabling technology that resolves noisy sensor data and abstracts it into higher-level concepts that are interesting to applications. 

In this talk, I will provide a comprehensive analysis of the nature and characteristics of situations, discuss the complexities of situation identification, and introduce a novel situation identification technique called “context lattice”. The context lattice is built on a sound mathematical model, aiming to identify situations by systematically exploring the semantics of sensor data, domain knowledge, and situations in a pervasive computing system. I will present and discuss the evaluation results when applying this technique to recognising human activities in smart home environments. This talk will be concluded with challenging questions in the area of situation identification.
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Event details

  • When: 3rd October 2011 14:00 - 15:00
  • Where: Cole 1.33
  • Series: CS Colloquia Series
  • Format: Colloquium

Measuring the Effectiveness of Abstract Data Visualisations

Speaker: Mark Shovman, University of Abertay, Dundee

Abstract:
In natural and social sciences, novel insights are often derived from visual analysis of data. But what principles underpin the extraction of meaningful content from these visualisations? Abstract data visualisation can be traced at least as far back as 1801; but with the increase in the quantity and complexity of data that require analysis, standard tools and techniques are no longer adequate for the task. The ubiquity of computing power enables novel visualisations that are rich, multimodal and interactive; but what is the most effective way to exploit this power to support analysis of large, complex data sets? Often, the lack of fundamental theory is pointed out as a central ‘missing link’ in the development and assessment of efficient novel visualisation tools and techniques.

In this talk, I will present some first steps towards the theory of visualisation comprehension, drawing heavily on existing research in natural scene perception and reading comprehension. The central inspiration is the Reverse Hierarchy Theory of perceptual organisation, which is a recent (2002) development of the near-centennial Laws of Gestalt. The proposed theory comes complete with a testing methodology (the ‘pop-out’ effect testing) that is based on our understanding of the cognitive processes involved in visualisation comprehension.

About Mark:
Mark Shovman is a SICSA Lecturer in Information Visualisation in the Institute of Arts, Media and Computer Games Technology in the University of Abertay Dundee. He is an interdisciplinary researcher, studying the perception and cognition aspects of information visualisations, computer games, and immersive virtual reality. His recent research projects include the application of dynamic 3D link-charts in Systems Biology; alleviating cyber-sickness in VR helmets; and immersive VR as an art medium. Mark was born in Tbilisi, Georgia, and lived in Jerusalem, Israel since 1990. He can be found on http://www.linkedin.com/pub/mark-shovman/3/a4b/849

Event details

  • When: 13th September 2011 14:00 - 15:00
  • Where: Cole 1.33a
  • Format: Seminar

MSc Poster Presentations 2011

The MSc poster presentations and project demonstrations took place this afternoon. We wish all of our MSc students good luck as they finish their dissertations and move closer to graduation!

Event details

  • When: 31st August 2011 14:00 - 16:00
  • Where: Honey 110 - MSc Lab

Summer school “Advanced techniques in computer algebra systems development”

The summer school “Advanced techniques in computer algebra systems development” is organised by the Centre of Interdisciplinary Research in Computational Algebra and supported by the Scottish Informatics and Computer Science Alliance (SICSA) and the EU FP6 project “SCIEnce – Symbolic Computation Infrastructure for Europe” Further details>>>

Event details

  • When: 29th August 2011 - 1st September 2011
  • Where: Maths Theatre A
  • Format: Summer School

Security and Privacy in mHealth systems

Mobile computing and sensing technologies present exciting opportunities for healthcare. Wireless sensors worn by patients can automatically deliver medical
sensor data to care providers, family members, or other caregivers, providing new opportunities to diagnose, monitor, and manage a wide range of medical
conditions. Using the mobile phones that patients already carry to provide connectivity between sensors and providers can help to keep costs low and
deployments simple. However, there are many security and privacy challenges involved in developing a system that will protect the patient’s privacy and the
integrity of the data collected. In this talk I describe the advent of these “mHealth” systems, survey the security and privacy issues, and describe research
underway at Dartmouth to address these challenges.

Biography

David Kotz is the Champion International Professor, in the Department of Computer Science, and Associate Dean of the Faculty for the Sciences, at Dartmouth
College in Hanover NH. During the 2008-09 academic year he was a Visiting Professor at the Indian Institute of Science, in Bangalore India, and a Fulbright
Research Scholar to India. At Dartmouth, he was the Executive Director of the Institute for Security Technology Studies from 2004-07. His research interests
include security and privacy, pervasive computing for healthcare, and wireless networks. He has published over 100 refereed journal and conference papers. He
is an IEEE Fellow, a Senior Member of the ACM, a member of the USENIX Association, and a member of Phi Beta Kappa.
After receiving his A.B. in Computer Science and Physics from Dartmouth in 1986, he completed his Ph.D in Computer Science from Duke University in 1991 and
returned to Dartmouth to join the faculty. For more information see http://www.cs.dartmouth.edu/~dfk/.

Event details

  • When: 22nd August 2011 11:30 - 12:30
  • Where: Cole 1.33a
  • Format: Seminar, Talk

Energy-efficient location-awareness on mobile devices

Speaker: Peterri Nurmi,  Helsinki Institute for Information Technology HIIT
Abstract:
Contemporary mobile phones readily support different positioning techniques. In addition to integrated GPS receivers, GSM and WiFi can be used for position estimation, and other sensors such as accelerometers and digital compasses can be used to support positioning, e.g., through dead reckoning or the detection of stationary periods. Selecting which sensor technologies to use for positioning is, however, a non-trivial task as available sensor technologies vary considerably in terms of their energy demand and the accuracy of location estimates. To improve the energy-efficiency of mobile devices and to provide as accurate position estimates as possible, novel on-device positioning technologies together with techniques that select optimal sensor modalities based on positioning accuracy requirements are required. In this talk we first introduce novel GSM and WiFi fingerprinting algorithms that run directly on mobile devices with minimal energy consumption [1]. We also introduce our recent work on minimizing the power consumption of continuous location and trajectory tracking on mobile devices [2].
[1] P. Nurmi, S. Bhattacharya, J. Kukkonen: “A grid-based algorithm for on-device GSM positioning.” Proc. 12th ACM International Conference on Ubiquitous Computing (Ubicomp, Copenhagen, Denmark, September 2010). ACM Press, 2010, 227-236.
[2] M. B. Kjaergaard, S. Bhattacharya, H. Blunck, P. Nurmi, “Energy-efficient Trajectory Tracking for Mobile Devices”, Proc. 9th International Conference on Mobile Systems, Applications and Services (MobiSys, June-July, 2011).

About Petteri:
Dr. Petteri Nurmi is a Senior Researcher at the Helsinki Institute for Information Technology HIIT. He received a PhD in Computer Science from the University of Helsinki in 2009. He is currently co-leading the Adaptive Computing research group at HIIT together with Doc. Patrik Floréen. His research focuses on ubiquitous computing, user modeling and interaction with a view of making the life of ordinary people easier through easy-to-use mobile services. He regularly serves as Program Committee Member and reviewer for numerous leading conferences and journals. More information about his research can be found from the webpage of the research group: http://www.hiit.fi/adapc/

Event details

  • When: 29th July 2011 12:00 - 13:00
  • Where: Cole 1.33a
  • Format: Seminar

Sensing, understanding and modelling people using mobile phones

Speaker: Mirco Musolesi, Computer Science, University of St Andrews

Abstract:

Mobile phones are increasingly equipped with sensors, such as accelerometers, GPS receivers, proximity sensors and cameras, that can be used to sense and interpret people behaviour in real-time. Novel user-centered sensing applications can be built by exploiting the availability of such technologies in these devices that are part of our everyday experience. Moreover, data extracted from the sensors can also be used to model people behaviour and movement patterns providing a very rich set of multi-dimensional data, which can be extremely useful for social science, marketing and epidemiological studies.

In this talk I will present some of my recent work in this area including the design and implementation of the CenceMe platform, a system that supports the inference of activities and other presence information of individuals using off-the-shelf sensor-enabled phones and of EmotionSense, a system for supporting social psychology research. Finally, I will discuss the issues related to the design of energy-efficient social sensing systems.

About Mirco:

Dr. Mirco Musolesi is a SICSA Lecturer at the School of Computer Science at the University of St. Andrews. He received a PhD in Computer Science from University College London in 2007 and a Master in Electronic Engineering from the University of Bologna in 2002. From October 2005 to August 2007 he was a Research Fellow at the Department of Computer Science, University College London. Then, from September 2007 to August 2008 he was an ISTS Postdoctoral Research Fellow at Dartmouth College, NH, USA, and from September 2008 to October 2009 a Postdoctoral Research Associate at the Computer Laboratory, University of Cambridge. His research interests lie in the broad area of mobile systems and networking with a current focus on intelligent mobile systems, online social networks, application of complex network theory to networked systems design, mobility modelling and sensing systems based on mobile phones. More information about his research profile can be found at the following URL: http://www.cs.st-andrews.ac.uk/~mirco

Event details

  • When: 26th July 2011 13:00 - 14:00
  • Where: Cole 1.33a
  • Format: Seminar

Narrative Generation: a case study in assistive technology

Speaker: Nava Tintarev, University of Aberdeen

Abstract:
Story-telling, (including personal narrative), is a big part of our personal and social communication. This talk will identify challenges and solutions that look at the generation of narrative for social communication. We describe a way to “automatically” generate personal stories. The stories which are mix of natural language and multimedia, are based on sensor, and other data, collected with a mobile phone. This study will place a particular focus on the natural language generation task of document structuring: segmenting this data into meaningful and distinct events.
About Nava:
Nava Tintarev has worked on applied HCI projects with themes such as explanations in recommender systems, recommendations in
a mobile travel scenario, and more recently, natural language generation for assistive technology.

Currently, she is working as a Research Fellow at the University of Aberdeen where she is a member of the Natural Language Generation Group.
She has been working on the “How was School today…?” project, which helps children with complex communication needs create and tell a story
about their day at school (which will be the applied setting for the talk on the 19th of July). Before that, she was at Telefónica Research, Barcelona,
working on user-centred issues in recommender systems.
Her doctoral thesis focused on explanations for recommender systems, and one of her papers on the topic
won her the James Chen best student paper award at the International Conference on Hypermedia (2008). For the last
three years she has also been co-organizing a workshop on explanation-aware computing (ExaCt) (http://exact2011.workshop.hm/).

Event details

  • When: 19th July 2011 13:00 - 14:00
  • Where: Cole 1.33a
  • Format: Seminar