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Complexity of Human Language ComprehensionRistad, Eric Sven 01 December 1988 (has links)
The goal of this article is to reveal the computational structure of modern principle-and-parameter (Chomskian) linguistic theories: what computational problems do these informal theories pose, and what is the underlying structure of those computations? To do this, I analyze the computational complexity of human language comprehension: what linguistic representation is assigned to a given sound? This problem is factored into smaller, interrelated (but independently statable) problems. For example, in order to understand a given sound, the listener must assign a phonetic form to the sound; determine the morphemes that compose the words in the sound; and calculate the linguistic antecedent of every pronoun in the utterance. I prove that these and other subproblems are all NP-hard, and that language comprehension is itself PSPACE-hard.
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Hard and soft conditions on the faculty of language : constituting parametric variationZeijlstra, Hedde January 2009 (has links)
In this paper I argue that both parametric variation and the alleged differences between languages in terms of their internal complexity straightforwardly follow from the Strongest Minimalist Thesis that takes the Faculty of Language (FL) to be an optimal solution to conditions that neighboring mental modules impose on it. In this paper I argue that hard conditions like legibility at the linguistic interfaces invoke simplicity metrices that, given that they stem from different mental modules, are not harmonious. I argue that widely attested expression strategies, such as agreement or movement, are a direct result of conflicting simplicity metrices, and that UG, perceived as a toolbox that shapes natural language, can be taken to consist of a limited number of markings strategies, all resulting from conflicting simplicity metrices. As such, the contents of UG follow from simplicity requirements, and therefore no longer necessitate linguistic principles, valued or unvalued, to be innately present. Finally, I show that the SMT does not require that languages themselves have to be optimal in connecting sound to meaning.
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The 3rd international IEEE scientific conference on physics and control (PhysCon 2007) : September 3rd-7th 2007 at the University of PotsdamJanuary 2007 (has links)
During the last few years there was a tremendous growth of scientific activities in the fields related to both Physics and Control theory: nonlinear dynamics, micro- and nanotechnologies, self-organization and complexity, etc. New horizons were opened and new exciting applications emerged. Experts with different backgrounds starting to work together need more opportunities for information exchange to improve mutual understanding and cooperation. The Conference "Physics and Control 2007" is the third international conference focusing on the borderland between Physics and Control with emphasis on both theory and applications. With its 2007 address at Potsdam, Germany, the conference is located for the first time outside of Russia. The major goal of the Conference is to bring together researchers from different scientific communities and to gain some general and unified perspectives in the studies of controlled systems in physics, engineering, chemistry, biology and other natural sciences. We hope that the Conference helps experts in control theory to get acquainted with new interesting problems, and helps experts in physics and related fields to know more about ideas and tools from the modern control theory.
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Narrating Entrepreneurship: a Complexity Adaptive System PerspectiveLin, Shao-yi 13 August 2007 (has links)
In the past, most entrepreneurship researches were constructed on static, unilateral, single-level perspectives. They were used to adopt logic positivism as methodology so that it¡¦s hard to see the dynamic process of entrepreneurship. In this paper, I avoid following such paradigm and seek a novel solution in entrepreneurship study. I adopt complexity adaptive system (CAS) as a new theoretical perspective and narrative inquiry as a fresh methodology. In this way, entrepreneurship is viewed as a dynamic process, and all the accounts are arranged in four entrepreneurship stories: ¡§The first step : far from equilibrium¡¨, ¡§Strange attractors : vision and core capability¡¨, ¡§Dawn of the chaos : self-organization¡¨, and ¡§The pattern accompanied innovation: emergence¡¨.
Through the lens of CAS, this research expresses that successful entrepreneurship is simply not the result of perfect planning in advance or opportunity identification. In fact, entrepreneurs try to enact self-organizing through interactions with the outsiders and finally generate innovation. Organizations should view chaos as normal condition thus they can keep evolution to survive. With these metaphors, the research attempt to inspire entrepreneurs and make their entrepreneurship come off.
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Det är enklare i teorin...Om skolutveckling i praktiken : En fallstudie av ett skolutvecklingsprojekt i en gymnasieskolavon Schantz Lundgren, Inger January 2008 (has links)
This dissertation is a case study dealing with a school development project that took place in an upper secondary school as a result of a merger of two schools with different cultures. The project used a method called “Frirumsmodellen” and was planned to be conducted in three steps. The first was to carry out a cultural analysis in order to map the preconditions to start a school development project. The second was to carry out concrete actions and finally study eventual effects from such activities by doing a second cultural analysis. My role was to be a supervisor in the school development work, but at the same time study how this work was conducted and its impact in the ordinary school day. The dissertation takes its departure in the fact that schools are political governed. The mission of schools is never neutral; it is always an expression of behind laying social forces, ideologies and ideals of the contemporary society. Of this reason, there is a close connection between the macro political level and the micro political level. Another point of departure is the transition from a modern to a post modern society that gives the character to the changes that take place in schools. Steering of schools has partly been treated as a technical implementation problem. Schools contain on going conflicts between different interest groups that, more or less regularly, end up in educational reforms. These reforms generate school development activities in the single school. Undoubtedly, this makes school development to a complex process. At a rather late stage of the study I decided not to fulfil my task to follow the original plan. I instead let the school development project as a model to be in focus. The over all purpose was formulated: How is it possible to understand what happened in the school development project in the Falkgymnasiet and why was it not possible to carry it out as it was said in the project plan? To interpret what took place during the project I did create an interpretation frame of implementation and complexity theory that also made it possible to critically scrutinise the “Frirumsmodellen”. Already in an early stage of the process it was obvious that the “Frirumsmodellen” did not supply any tools to use and it became disconnected from the project. The project in it selves was marginalised and made invisible. The headmaster used the situation to change things she thought were important to develop. As a result, things happened, but most of the involved people did not at first hand connect this to the project. It is, of course, difficult in detail to say what caused what. The complexity theory successively made the hidden patterns revealed, hidden unofficial potentates visible, as well as unpredictable conditions that generated reactions from the personnel in front of a development work. Together this was rather efficient obstacles for not changing this school. I also discuss school development and implementation problems on a general level, for example, the possibility to transform a top-down initiated project to be bottom-up driven and using project as a tool for school development work. It was obvious that headmasters and teachers must be prepared to handle the ideological dimensions of problems schools have to face. Consequently, development work is about making problems visible and to handle these in the intersection point between the intentions of educational policies, pedagogical researchers, school administrators, headmasters, teachers and pupils. The ideological dimension also contains an existential issue. Do I as a teacher share the intentions for the development work? If not, how must I act?
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Marketing Your Intangible Future : Tangibilization of Retirement Savings at Handelsbanken and SwedbankLarsson, Emelie, Södersten, Marianne January 2008 (has links)
The purpose of this study is to investigate how individual retirement savings are made tangible for potential customers. As case companies we have studied the marketing strategies of Handelsbanken and Swedbank. We use Miller and Foust’s classification of services by intangibility based on attributes and benefits and Tarn’s four strategy marketing-based model in order to find out how the retirement savings are made tangible. We find that the attributes and benefits that are used to define retirement savings depend on how the service is affiliated to life-insurance or banking services. Intangibility is coped by simplifying the products by lifting forward salient features. Complexity is overcome by explanation. Putting emphasis on flexibility is a mean to cope with the uncertainty of future income.
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Effects of Temperature on the Kinetic Isotope Effects for Proton and Hydride Transfers in the Active Site Variant of Choline Oxidase Ser101AlaUluisik, Rizvan C 23 May 2013 (has links)
Choline oxidase catalyzes the oxidation of choline to glycine betaine. The reaction includes betaine aldehyde as an intermediate. FAD is reduced by the alcohol substrate, betaine aldehyde intermediate and oxidized by molecular oxygen to give hydrogen peroxide. In this study, the Ser101Ala variant of choline oxidase was prepared to elucidate the contribution of the hydroxyl group of Ser101 in the proton and hydride transfer reactions for proper preorganization and reorganization of the active site towards quantum mechanical tunneling. The thermodynamic parameters associated with the enzyme-catalyzed OH and CH bond cleavages and the temperature dependence of the associated solvent and substrate kinetic isotope effects were investigated using a stopped-flow spectrophotometer. The proton and hydride transfer have been shown to be occurring via quantum tunneling in CHO-S101A enzyme.
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On the Complexity of Finding Spanner PathsNilsson, Mikael January 2013 (has links)
We study the complexity of finding so called spanner paths between arbitrary nodes in Euclidean graphs. We study both general Euclidean graphs and a special type of graphs called Integer Graphs. The problem is proven NP-complete for general Euclidean graphs with non-constant stretches (e.g. (2n)^(3/2) where n denotes the number of nodes in the graph). An algorithm solving the problem in O(2^(0.822n)) is presented. Integer graphs are simpler and for these special cases a better algorithm is presented. By using a partial order of so called Images the algorithm solves the spanner path problem using O(2^(c(\log n)^2)) time, where c is a constant depending only on the stretch.
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Expansion, Random Graphs and the Automatizability of ResolutionZabawa, Daniel Michael 25 July 2008 (has links)
We explore the relationships between the computational problem of recognizing expander graphs, and the problem of efficiently approximating proof length in the well-known system of \emph{resolution}. This program builds upon known connections between graph expansion and resolution lower bounds.
A proof system $P$ is \emph{(quasi-)automatizable} if there is a search algorithm which finds a $P$-proof of a given formula $f$ in time (quasi)polynomial in the length of a shortest $P$-proof of $f$. It is open whether resolution is (quasi-)automatizable. We prove several conditional non-automatizability results for resolution modulo new conjectures concerning the complexity of identifying bipartite expander graphs. Our reductions use a natural family of formulas and exploit the well-known relationships between expansion and length of resolution proofs. Our hardness assumptions are unsupported; we survey known results as progress towards establishing their plausibility. The major contribution is a conditional hardness result for the quasi-automatizability of resolution.
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Topological entanglement complexity of systems of polygons and walks in tubesAtapour, Mahshid 09 September 2008
In this thesis, motivated by modelling polymers, the topological entanglement complexity of systems of two self-avoiding polygons (2SAPs), stretched polygons and systems of self-avoiding walks (SSAWs) in a tubular sublattice of Z3 are investigated. In particular, knotting and linking probabilities are used to measure a polygonfs selfentanglement and its entanglement with other polygons respectively. For the case of 2SAPs, it is established that the homological linking probability goes to one at least as fast as 1-O(n^(-1/2)) and that the topological linking probability goes to one exponentially rapidly as n, the size of the 2SAP, goes to infinity. For the case of stretched polygons, used to model ring polymers under the influence of an external
force f, it is shown that, no matter the strength or direction of the external force, the knotting probability goes to one exponentially as n, the size of the polygon, goes to infinity. Associating a two-component link to each stretched polygon, it is also proved that the topological linking probability goes to unity exponentially fast as n→∞. Furthermore, a set of entangled chains confined to a tube is modelled by a system of self- and mutually avoiding walks (SSAW). It is shown that there exists a positive number γ such that the probability that an SSAW of size n has entanglement complexity (EC), as defined in this thesis, greater than γn approaches one exponentially as n→∞. It is also established that EC of an SSAW is bounded above by a linear function of its size. Using a transfer-matrix approach, the asymptotic form of
the free energy for the SSAW model is also obtained and the average edge-density for span m SSAWs is proved to approach a constant as m→∞. Hence, it is shown that EC is a ggoodh measure of entanglement complexity for dense polymer systems modelled by SSAWs, in particular, because EC increases linearly with system size, as the size of the system goes to infinity.
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