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Premonoidal *-Categories and Algebraic Quantum Field TheoryComeau, Marc A 16 March 2012 (has links)
Algebraic Quantum Field Theory (AQFT) is a mathematically rigorous framework
that was developed to model the interaction of quantum mechanics and relativity. In
AQFT, quantum mechanics is modelled by C*-algebras of observables and relativity
is usually modelled in Minkowski space. In this thesis we will consider a generalization
of AQFT which was inspired by the work of Abramsky and Coecke on abstract
quantum mechanics [1, 2]. In their work, Abramsky and Coecke develop a categorical
framework that captures many of the essential features of finite-dimensional quantum
mechanics.
In our setting we develop a categorified version of AQFT, which we call premonoidal
C*-quantum field theory, and in the process we establish many analogues of
classical results from AQFT. Along the way we also exhibit a number of new concepts,
such as a von Neumann category, and prove several properties they possess.
We also establish some results that could lead to proving a premonoidal version
of the classical Doplicher-Roberts theorem, and conjecture a possible solution to constructing
a fibre-functor. Lastly we look at two variations on AQFT in which a causal
order on double cones in Minkowski space is considered.
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Premonoidal *-Categories and Algebraic Quantum Field TheoryComeau, Marc A January 2012 (has links)
Algebraic Quantum Field Theory (AQFT) is a mathematically rigorous framework
that was developed to model the interaction of quantum mechanics and relativity. In
AQFT, quantum mechanics is modelled by C*-algebras of observables and relativity
is usually modelled in Minkowski space. In this thesis we will consider a generalization
of AQFT which was inspired by the work of Abramsky and Coecke on abstract
quantum mechanics [1, 2]. In their work, Abramsky and Coecke develop a categorical
framework that captures many of the essential features of finite-dimensional quantum
mechanics.
In our setting we develop a categorified version of AQFT, which we call premonoidal
C*-quantum field theory, and in the process we establish many analogues of
classical results from AQFT. Along the way we also exhibit a number of new concepts,
such as a von Neumann category, and prove several properties they possess.
We also establish some results that could lead to proving a premonoidal version
of the classical Doplicher-Roberts theorem, and conjecture a possible solution to constructing
a fibre-functor. Lastly we look at two variations on AQFT in which a causal
order on double cones in Minkowski space is considered.
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Grothendieck Group Decategorifications and Derived Abelian CategoriesMcBride, Aaron January 2015 (has links)
The Grothendieck group is an interesting invariant of an exact category. It induces a decategorication from the category of essentially small exact categories (whose morphisms are exact functors) to the category of abelian groups. Similarly, the triangulated Grothendieck group induces a decategorication from the category of essentially small triangulated categories (whose morphisms are triangulated functors) to the category of abelian groups. In the case of an essentially small abelian category, its Grothendieck group and the triangulated Grothendieck group of its bounded derived category are isomorphic as groups via a natural map. Because of this, homological algebra and derived functors become useful in surprising ways. This thesis is an expository work that provides an overview of the theory of Grothendieck groups with respect to these decategorications.
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SOME MEASURED PERFORMANCE BOUNDS AND IMPLEMENTATION CONSIDERATIONS FOR THE LEMPEL-ZIV-WELCH DATA COMPACTION ALGORITHMJacobsen, H. D. 10 1900 (has links)
International Telemetering Conference Proceedings / October 26-29, 1992 / Town and Country Hotel and Convention Center, San Diego, California / Lempel-Ziv-Welch (LZW) algorithm is a popular data compaction technique that has been
adopted by CCITT in its V.42bis recommendation and is often implemented in association
with the V.32 standard for 9600 bps modems. It has also been implemented as Microcom
Networking Protocol (MNP) Level 7, where it goes by the name of Enhanced Data
Compression. LZW compacts data by encoding frequently occurring input strings with a
single output symbol. The algorithm automatically generates a string dictionary for each
symbol at each end of the transmission path. The amount of compaction that can be
derived with the LZW algorithm varies with the type of data being transmitted and the
efficiency by which table entries can be indexed. Table indexing is usually implemented by
use of a hashing table. Although some manufacturers advertise a 4-to-1 gain in throughput,
this seems to be an extreme case. This paper documents a implementation of the exact
ZLW algorithm. The results presented in this paper are significantly less, typically on the
order of 1-to-2 for ASCII text, with substantially less compaction for pre-compacted files
or files containing random bit patterns.
The efficiency of the LZW algorith on ASCII text is shown to be a function of dictionary
size and block size. Although fewer transmitted symbols are required for larger dictionary
tables, the additional bits required for the symbol index is marginally greater than the
efficiency that is gained. The net effect is that dictionary sizes beyond 2K in size are
increasingly less efficient for input data block sizes of 10K or more. The author concludes
that the algorithm could be implemented as a direct table look-up rather than through a
hashing algorithm. This would allow the LZW to be implemented with very simple
firmware and with a maximum of hardware efficiency.
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Reevaluating the determinants of category-based inductionRein, Jonathan Raymond, 1983- 21 September 2010 (has links)
What makes one more or less likely to project a novel property from an item to that item’s broader category? Research on category-based induction has documented a consistent typicality effect: typical exemplars promote stronger inferences than atypical exemplars. This work has been largely confined to categories whose central tendencies are the most typical members of the category. Experiments 1 and 2, using natural and artificial categories, showed that central tendencies have greatest induction strength even for categories that are best represented by ideal exemplars. Experiments 3-7 investigate the role of familiarity in induction. Experiments 3 and 4 directly contrast statistical averageness against familiarity through category learning procedures. Experiment 5 creates this contrast through frequency differences across stimuli. Experiments 6 and 7 investigate how the familiarity advantage found in Experiments 3-5 can be modified
through fluency manipulations, independent of actual experience. Taken together, these studies suggest that category-based induction is driven largely by a familiarity heuristic. / text
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Categorical model structuresWilliamson, Richard David January 2011 (has links)
We build a model structure from the simple point of departure of a structured interval in a monoidal category — more generally, a structured cylinder and a structured co-cylinder in a category.
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Performance of Brain-Injured versus Non-Brain-Injured Individuals on Three Versions of the Category TestMercer, Walt N. (Walt Neilson) 08 1900 (has links)
To date, no research exists examining criterion-related validity of alternate, computerized forms of the Category Test. The intent of this study was to address criterion-related validity of three full forms of the Category Test. In that, the goal was to examine equivalency of each version in their ability to differentiate brain-injured from non-brain-injured individuals. Forty-nine (N = 49) healthy adults and 45 (N = 45) brain-injured adults were tested using three versions of the Category Test, the BDI, and the WAIS-R NI. ANOVA indicated no significant differences between versions of the Category Test or an interaction between Category Test version and group membership on the total error score. MANOVA performed between versions of the Category Test and Subtest error scores indicated significant differences between versions on Subtest 3 and Subtest 6. Group membership (brain-injured v. non-brain-injured) produced a significant main effect on all subtests of the Category Test except Subtest 2. Several exploratory analyses were performed examining the relationship between neuropsychological impairment, group membership based on Category Test error scores, and the WAIS-R NI. Clinical applications, such as the use of serial testing to index neurorehabilitation gains, were discussed.
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Topics in Category TheoryMiller, Robert Patrick 08 1900 (has links)
The purpose of this paper is to examine some basic topics in category theory. A category consists of a class of mathematical objects along with a morphism class having an associative composition. The paper is divided into two chapters. Chapter I deals with intrinsic properties of categories. Various "sub-objects" and properties of morphisms are defined and examples are given. Chapter II deals with morphisms between categories called functors and the natural transformations between functors. Special types of functors are defined and examples are given.
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Přístrojové vybavení pilota paraglidingu / Device equipement of the paragliding pilotMrázek, Martin January 2012 (has links)
Name of thesis Flight equipment and its importance in efficiency categories of paragliding Abstract: The goals The goal of this thesis is to find out appropriate instruments and the dependence of their using on the performance category of pilot. Practical contribution of this thesis will be find out the most frequent usage of the instruments between pilots and how important they are for pilots. Methods The thesis is compiled in the form of quantitative research. For the collection of data we have chosen questionnaries, which were situated in a paragliding web. Results Detected facts represent that with increasing efficiency category, the count of respondents, for who instruments are important, is increased. The next fact represent, that with increasing efficiency category, the count of respondents, who have and use instruments, is increased. The most important instrument for all efficiency categories is variometr and then GPS. Key words Paragliding, instruments, efficiency category, importance.
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Category Management : The effective way of managing retail business.RASHID, MD. SANUWAR January 2010 (has links)
Today’s fragmented and intensely competitive market place is the obstacle for retailers and suppliers to do business in a traditional way. Even customers have never been more sophisticated. In this perspective, thousands of idea has already been brought though articles, journals and books and thousands of seminars has been hold to define a new way of managing business. Just as an tremendous heat and pressure create diamond, these uncertainties and competitive challenges has produced a new marketing ideas known as category management that offers an wealth of opportunity for those who can adopt with this systematic approach. In this thesis, some definition and structure-oriented phases as well as the challenging area of category management are mentioned. In the next step, a perfect scenario through different stages starting from zero is brought out to show how retailers and suppliers can overcome the power game and collaborate with each other. Finally I have shown that a trust worthy relationship, coupled with in-store implementation of category management, can create a win-win situation for both retailers and suppliers. / Program: Magisterutbildning i Applied Textile Management
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