Systems software, such as an operating system or a network stack, underlies everything we do on a computer, whether that computer is a desktop machine, a server, a mobile phone, or any embedded device. It is therefore vital that such software operates correctly in all situations. In recent years, dependent types have emerged as a promising approach to ensuring program correctness using languages and verification tools such as Agda and Coq. However, these tools operate at a high level of abstraction and so it can be difficult to map these verified programs to efficient low level code, working with bit-level operations and interacting directly with system services.

In this talk I will describe Idris, a dependently typed programming language implemented with systems programming in mind. I will show how it may be used to implement programs which interact safely with the operating system, in particular how to give precise APIs for verifiable systems programming with external C libraries.

Bio: Edwin Brady is a SICSA Advanced Research Fellow at the University of St Andrews
(http://www.cs.st-andrews.ac.uk/~eb)

Many ‘failures’ in software-intensive organisational systems result from human actions or inaction so, to reduce the possibility of such ‘failures’ and so improve system dependability, it is important to adopt a holistic view where system designers consider the environment in which a system will be used as well as the technical characteristics of the system itself.

In this talk, I will introduce the notion of responsibility modelling, which aims to represent the responsibilities of human and automated agents in a complex system, where the system may be created by integrating different systems from different agencies. The motivation for the work is that many ‘system failures’ are actually failures of agents in the system to fulfil their expected responsibilities and so responsibility modelling offers the opportunity to analyse how responsibilities are distributed and to identify responsibility vulnerabilities, before these lead to system failure.

Bio

 Ian Sommerville has been Professor of Computer Science at St Andrews University since 2006. For more details see http://www.software-engin.com.

In this talk we will introduce how new mobile base station architectures are evolving not only to meet demand but also to become “greener” since at current rates of deployment, mobile networks are becoming very large CO2 contributors. These new base station architectures are also becoming enablers for new Radio Access Networks (RANs) where the same infrastructure can support multiple radio technologies simultaneously by backhauling their baseband leading towards distributed antenna systems and distributed base station architectures. Some would argue that this represents a paradigm shift towards “cloud” enabled mobile networks. In the talk we will cover the reasons why things are progressing this way, how this is being enabled through technology innovation, and what Agilent has done to meet some of the test and measurement challenges in this evolved 4G wireless communications space.

Abstract:

In Capability and Wellbeing, Sen (1993) says that acting freely and being able to choose may be directly conducive to wellbeing, not just because more freedom may make better alternatives available, but because the action of choice is itself a freedom. This talk reflects on three projects with older people and considers their sense of agency in thinking about interactive systems and future technologies, looking particularly at how agency might contribute to a sense of wellbeing. Although a theme running through the talk is the design of digital tools, the discussion takes a broad view of the factors to be considered in human-computer interaction.

Sen, Amartya. (1993). Capability and Well-Being. In M. Nussbaum and A. Sen, eds. The Quality of Life, pp. 30–53. New York: Oxford University Press.

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Abstract

The human visual system is extraordinary powerful, but it is not a perfect seeing device. In this talk I will use the example of binocular vision to explore visual processing. I will describe some of the biology of the binocular visual system, some of the limitations that the biology presents, and I will describe methods used to probe the relative importance of binocular vision, versus other sources of 3-D visual information. These methods allow us to predict where and when binocular vision provides a powerful source of 3-D information, and is therefore useful to inform the design and production of devices across a range of HCI applications.

Bio


Julie Harris is interested in visual perception, with particular interests in how binocular vision and eye movements are used for the perception of shape and depth and the control of action in 3-D space. Current projects include how binocular information is used for distance perception, how gaze patterns can be described in simple mathematical terms, and how we perceive motion in three dimensions.

Abstract

Despite Moore’s “law”, uniprocessor clock speeds have now stalled. Rather than using single processors running at ever higher clock speeds, it is common to find dual-, quad- or even hexa-core processors, even in consumer laptops and desktops. Future hardware will not be slightly parallel, however, as in today’s multicore systems, but will be massively parallel, with manycore and perhaps even megacore systems becoming mainstream. This means that programmers need to start thinking parallel. To achieve this they must move away from traditional programming models and development processes that offer parallelism as an bolted-on afterthought.

This talk introduces the idea of “paraforming”, a new approach to constructing parallel functional programs using formally-defined refactoring transformations.
We show how parallel programs can be built from a small number of primitive Haskell building blocks, and describe some new refactorings for Parallel Haskell that capture common parallel abstractions, such as divide-and-conquer and data parallelism using these building blocks. Using a paraforming approach, we are able to easily obtain significant and scalable speedups (up to 7.8 on an 8-core machine).

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Opportunistic networks provide an ad hoc communication medium without the need for an infrastructure network, by leveraging human encounters and mobile devices. Routing protocols in opportunistic networks frequently rely upon encounter histories to build up meaningful data to use for informed routing decisions. This seminar presents work showing it is possible to use pre-existing social-network information to improve existing opportunistic routing protocols, and that these self-reported social networks have a particular benefit when used to bootstrap an opportunistic routing protocol.

Frequently, opportunistic routing protocols require users to relay messages on behalf of one another: an act that incurs a cost to the relaying node. Nodes may wish to avoid this forwarding cost by not relaying messages. Opportunistic networks need to incentivise participation and discourage the selfish behaviour. This seminar further presents an incentive mechanism that uses self-reported social networks to construct and maintain reputation and trust relationships between participants, and demonstrates its superior performance over existing incentive mechanisms.

Greg Bigwood is a Ph.D. student in the School of Computer Science at the University of St Andrews. He works in the field of opportunistic networks and social networks, researching the use of social-network information to improve opportunistic networks.

He read Computer Science at the University of St Andrews, graduating in 2007.