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The deletion-contraction algorithm is perhaps the most popular method for computing a host of fundamental graph invariants such as the chromatic, flow, and reliability polynomials in graph theory, the Jones polynomial of an alternating link in knot theory, and the partition functions of the models of Ising, Potts, and Fortuin-Kasteleyn in statistical physics. Prior to this work, deletion-contracti

Popular Abstract in Swedish Denna studie betonar att de mekanismer, som skapar tillväxt, inte nödvändigtvis är universella utan kan skilja sig åt mellan olika områden, beroende på vad som produceras och vilken teknik som används. Avhandlingen hävdar inledningsvis att ekonomisk tillväxt är den viktigaste enskilda faktor som påverkar individers inkomstnivå och att ökad produktivitet i sin tur är gruThis study shows that the mechanisms behind knowledge accumulation and the sources of productivity growth differ from industry to industry depending on what is produced and what technology is used. Although it is apparent to most researchers in the field that the only way to explain long-run growth in output per capita is through technological progress and accumulation of knowledge that counteract

Photosynthesis is the process by which energy of light is converted into chemical energy by plants, algae and photosynthetic bacteria. For this, highly specialized pigment-proteins have evolved that capture the light and transform the short-lived excited states of pigment molecules into a stable transmembrane potential. By close scrutiny of organization and processes of the photosynthetic pigment

Regression testing is expensive and may consume much of organizations’ software development budgets. Thus, it is of interest to reduce the total time devoted to test execution by using test selection techniques. Many techniques have been proposed but few have been evaluated on real-world, large scale systems. In this paper we report on an empirical evaluation of using the class firewall regression

A recent study of ours suggested that the very presence of a Teachable Agent (TA) from a mathematics learning game might affect students’ test performance when the TA reappeared in the margin of a regular, digital math test. We hypothesized that this effect, which seemed to particularly target low-achievers, was due to the students’ mindset changing from that of “taking a test” to that of “teachin

This paper presents our contribution in the closed track of the 2008 CoNLL Shared Task. To tackle the problem of joint syntactic--semantic analysis, the system relies on a syntactic and a semantic subcomponent. The syntactic model is a bottom-up projective parser using pseudo-projective transformations, and the semantic model uses global inference mechanisms on top of a pipeline of classifiers. Th

For future robot control, there is a strong need for tools and methods supporting the development and deployment of control software. To this end, we propose a method for developing hard real-time software based on the standard Java language and multi-stage deployment and verification towards the embedded platform. This allows us to develop embedded Java software on the desktop using standard soft

A modularized approach to modeling of harmonics in electrical distribution networks at steady state is presented. It is based on harmonic balance and exploits that the loads in a distribution network are connected in parallel in such a way that their operating conditions are approximately known in advance (e.g. 230 V, 50 Hz) and the harmonic distortion of the voltage is limited. The model for a co

Control theory is emerging as a source of solutions for many problems in the computing systems domain, and in particular for resource allocation. However, the techniques proposed to date in the literature, do not successfully address the difficulty of devising allocation schemes that are general enough, provide stability guarantees, and can be parametrised and managed by system administrators, or

An important topic in the area of airborne sound propagation is the prediction of sound propagation above an impedance ground with an atmospheric profile whose sound speed varies with height. Even if this problem is simple in concept, it leads to complications for general velocity profiles. This work illustrates the existence of a large class of realistic atmospheric profiles for which analytical

This paper describes an original numerical prediction technique developed for the analysis of coupled vibro-acoustic problems in fluid waveguides. Specifically it is is a wave-based method. Unlike the conventional element-based methods, this technique uses wave functions that satisfy the governing equations to describe the dynamic variables exactly. One advantage is that fine domain discretization

It can be difficult to engage colleagues with the findings and recommendations of an externally-funded project, even when, or perhaps particularly when, it has major implications for institutional processes. The authors were involved with a large single-institution Higher Education change project that aimed to make the university more responsive to changes in curriculum needs, the student voice, e

In this paper we describe how to determine the time delays caused by synchronous and asynchronous control loops. These time delays can vary in a quite irregular way and can cause problems for the control loops closed over a communication network of, for instance, field-buses. Different setups allowing an arbitrary number of communication layers are analyzed. The theoretical derivations are illustr

An overview of the insertion devices (ID) activities at MAX IV Laboratory will be presented. This paper describes the current status of the MAX IV insertion devices and the first commissioning results of some of the first 12 IDs installed at the three accelerators in MAX IV laboratory. The IDs are two Elliptically Polarizing Undulators (EPU), two In-Vacuum Undulators (IVU) and one In-vacuum wiggle