The topic of exact, exponential-time algorithms for NP-hard problems has received a lot of attention, particularly with the focus of producing algorithms with stronger theoretical guarantees, e.g. ...

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Algorithms, Measures and Upper Bounds for Satisfiability and Related Problems

Modern equation-based object-oriented modeling languages which have emerged during the past decades make it easier to build models of large and complex systems. The increasing size and complexity o ...

/pdf/automatic-parallelization-of-equation-based-simulation-2dg910wgjy.pdf

Automatic Parallelization of Equation-Based Simulation Programs

This dissertation clarifies the role and relevance of the body in social interaction and cognition from an embodied cognitive science perspective. Theories of embodied cognition have during the past two decades offered a radical shift in explanations of the human mind, from traditional computationalism which considers cognition in terms of internal symbolic representations and computational processes, to emphasizing the way cognition is shaped by the body and its sensorimotor interaction with the surrounding social and material world. This thesis develops a framework for the embodied nature of social interaction and cognition, which is based on an interdisciplinary approach that ranges historically in time and across different disciplines. The theoretical framework presents a thorough and integrated understanding that supports and explains the embodied nature of social interaction and cognition. It is argued that embodiment is the part and parcel of social interaction and cognition in the most general and specific ways, in which dynamically embodied actions themselves have meaning and agency. The framework is illustrated by empirical work that provides some detailed observational fieldwork on embodied actions captured in three different episodes of spontaneous social interaction in situ. Besides illustrating the theoretical issues discussed in the thesis, the empirical work also reveals some novel characteristics of embodied action in social interaction and cognition. Furthermore, the ontogeny of social interaction and cognition is considered, in which social scaffolding and embodied experience play crucial roles during child development. In addition, the issue what it would take for an artificial system to be (socially) embodied is discussed from the perspectives of cognitive modeling and technology. Finally, the theoretical contributions and implications of the study of embodied actions in social interaction and cognition for cognitive science and related disciplines are summed up. The practical relevance for applications to artificial intelligence and human-computer interaction is also outlined as well as some aspects for future work.

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Minding the Body Interacting socially through embodied action

Mobile devices gain increasing computational power and storage capabilities, and there are already mobile phones that can show movies, act as digital music players and offer full-scale web browsing. The bottleneck for information flow is however limited by the inefficient communication channel between the user and the small device. The small mobile phone form factor has proven to be surprisingly difficult to overcome and limited text entry capabilities are in effect crippling mobile devices’ use experience. The desktop keyboard is too large for mobile phones, and the keypad too limited. In recent years, advanced mobile phones have come equipped with touch-screens that enable new text entry solutions. This dissertation explores how software keyboards on touch-screens can be improved to provide an efficient and practical text and command entry experience on mobile devices. The central hypothesis is that it is possible to combine three elements: software keyboard, language redundancy and pattern recognition, and create new effective interfaces for text entry and control. These are collectively called “shape writing” interfaces. Words form shapes on the software keyboard layout. Users write words by articulating the shapes for words on the software keyboard. Two classes of shape writing interfaces are developed and analyzed: discrete and continuous shape writing. The former recognizes users’ pen or finger tapping motion as discrete patterns on the touch-screen. The latter recognizes users’ continuous motion patterns. Experimental results show that novice users can write text with an average entry rate of 25 wpm and an error rate of 1% after 35 minutes of practice. An accelerated novice learning experiment shows that users can exactly copy a single well-practiced phrase with an average entry rate of 46.5 wpm, with individual phrase entry rate measurements up to 99 wpm. When used as a control interface, users can send commands to applications 1.6 times faster than using de-facto standard linear pull-down menus. Visual command preview leads to significantly less errors and shorter gestures for unpracticed commands. Taken together, the quantitative results show that shape writing is among the fastest mobile interfaces for text entry and control, both initially and after practice, that are currently known.

/pdf/discrete-and-continuous-shape-writing-for-text-entry-and-51ecip528c.pdf

Discrete and Continuous Shape Writing for Text Entry and Control

When performing predictive data mining, the use of ensembles is claimed to virtually guarantee increased accuracy compared to the use of single models. Unfortunately, the problem of how to maximize ...

/pdf/obtaining-accurate-and-comprehensible-data-mining-models-an-1xqlipv055.pdf

Obtaining Accurate and Comprehensible Data Mining Models : An Evolutionary Approach

The motivation for this thesis was the need for further development of multibody dynamics simulation packages focused on detailed contact analysis. The thesis makes contributions in three different ...

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Iakov Nakhimovski

Papers

Contributions to the Modeling and Simulation of Mechanical Systems with Detailed Contact Analyses