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Fast searching measurement of absolute displacement based on submicron-aperture fiber point-diffraction interferometerWang, Daodang, Wang, Zhichao, Liang, Rongguang, Kong, Ming, Zhao, Jun, Zhao, Jufeng, Mo, Linhai, Li, Wei 26 June 2017 (has links)
The submicron-aperture fiber point-diffraction interferometer (SFPDI) can be applied to realize the measurement of three-dimensional absolute displacement within large range, in which the performance of point-diffraction wavefront and numerical iterative algorithm for displacement reconstruction determines the achievable measurement accuracy, reliability and efficiency of the system. A method based on fast searching particle swarm optimization (FS-PSO) algorithm is proposed to realize the rapid measurement of three-dimensional absolute displacement. Based on the SFPDI with two submicron-aperture fiber pairs, FS-PSO method and the corresponding model of the SFPDI, the measurement accuracy, reliability and efficiency of the SFPDI system are significantly improved, making it more feasible for practical application. The effect of point-diffraction wavefront error on the measurement is analyzed. The error of point-diffraction wavefront obtained in the experiment is in the order of 1x10(-4). (the wavelength. is 532 nm), and the corresponding displacement measurement error is smaller than 0.03 mu m. Both the numerical simulation and comparison experiments have been carried out to demonstrate the accuracy and feasibility of the proposed SFPDI system, high measurement accuracy in the order of 0.1 mu m, convergence rate (similar to 90.0%) and efficiency have been realized with the proposed method, providing a feasible way to measure three-dimensional absolute displacement in the case of no guide rail.
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Stability of BDF-ADI DiscretizationsFelício dos Reis, João Miguel 17 August 2017 (has links)
We present new results on absolute stability for BDF-ADI (Backward differentiation formula Alternating Direction Implicit) methods applied to a linear advection and diffusion equations. Unconditional absolute stability of the BDF2-ADI method is proven for advection and diffusion separately, as well as to the BDF3-ADI method for the purely-diffusive case. Conditional absolute stability of the BDF4-ADI is also proven for the purely-diffusive case, and stability regions for BDF3-ADI and BDF4- ADI are given in terms of the PDE coefficients and numerical parameters. Lastly, numerical experiments are presented to support the theoretical results and conjectures. These experiments also suggest future work.
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Absolute Configuration and Biosynthesis of Pahayokolide A from Lyngbya sp. Strain 15-2 of the Florida EvergladesLiu, Li 01 November 2009 (has links)
Pahayokolides A-D are cytotoxic cyclic polypeptides produced by the freshwater cyanobacterium Lyngbya sp. strain 15-2 that possess an unusual β-amino acid, 3-amino-2,5,7,8-tetrahydroxy-10-methylundecanoic acid (Athmu). The absolute configuration of pahayokolides A-D was determined using advanced Marfey’s method. It was also confirmed that a pendant N-acetyl-N-methyl leucine moiety in pahayokolide A was absent in pahayokolides B and pahayokolides C-D were conformers of pahayokolide A. Feeding experiments indicated that the biosynthesis of the Athmu sidechain arises from leucine or α-ketoisovalerate, however could not be further extended by three rounds of condensation with malonate units. Putative four peptide and one unique polyketide synthetases in Lyngbya sp. strain 15-2 were identified by using a PCR method and degenerate primers derived from conserved core sequences of known NRPSs and PKSs. Identification of one unique KS domain conflicted with the logic rule that the long side chain of Athmu was assembled by three rounds of ketide extensions if PKSs were involved. A gene cluster (pah) encoding a peptide synthetase putatively producing pahayokolide was cloned, partially sequenced and characterized. Seven modules of the non-ribosomal peptide synthetase (NRPS) were identified. Ten additional opening reading frames (ORFs) were found, responsible for peptide resistance, transport and degradation. Although the predicted substrate specificities of NRPS agreed with the structure of pahayokolide A partially, the disagreement could be explained. However, no PKS gene was found in the pah gene cluster.
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Fractionation Resistance of Duplicate Genes Following Whole Genome Duplication in Plants as a Function of Gene Ontology Category and Expression LevelChen, Eric Chun-Hung January 2015 (has links)
With the proliferation of plant genomes being sequenced, assembled, and annotated, duplicate gene loss from whole genome duplication events, also known in plants as frac- tionation, has shown to have a different pattern from the classic gene duplication models described by Ohno in 1970. Models proposed more recently, the Gene Balance and Gene Dosage hypotheses, try to model this pattern. These models, however, disagree with each other on the relative importance of gene function and gene expression. In this thesis we explore the effects of gene function and gene expression on duplicate gene loss and retention.
We use gene sequence similarity and gene order conservation to construct our gene fam- ilies. We applied multiple whole genome comparison methods across various plants in rosids, asterids, and Poaceae in looking for a general pattern. We found that there is great consistency across different plant lineages. Genes categorized as metabolic genes with low level of expression have relatively low fractionation resistance, losing duplicate genes readily, while genes categorized as regulation and response genes with high level of expression have relatively high fractionation resistance, retaining more duplicate gene pairs or triples.
Though both gene function and gene expression have important effects on retention pattern, we found that gene function has a bigger effect than gene expression. Our results suggest that both the Gene Balance and Gene Dosage models account to some extent for fractionation resistance.
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Trust and Reputation Algorithms for Hierarchically Structured Peer-to-Peer SystemsKalala, Kalonji January 2017 (has links)
This research focuses on the redesign of trust and reputation algorithms in the context of hierarchically structured Peer-to-Peer (P2P) networks with Chord, a scalable P2P lookup service for Internet applications. Chord, which is an open source project, is an overlay network based on a distributed hash table(DHT), and all peers in Chord are arranged around a circle. In this work, we propose four adapted trust and reputation algorithms for hierarchically structured P2P networks: EigenTrust, PowerTrust, Absolute Trust and NodeRanking. EigenTrust is one of the most well-known trust and reputation algorithms, as well as the most simple. To calculate the reputation, EigenTrust needs to normalize trust and rely on pre-trusted peers. Like EigenTrust, PowerTrust relies on feedback and the use of a distributed ranking mechanism. It chooses a limited number of power nodes with a high reputation. By combining a random walk strategy and the power nodes, it improves accuracy of global reputation. AbsoluteTrust does not require normalization of trust, pretrusted peers or any centralized authority. Weighted average combined with feedback from peers is employed to determine trust. NodeRanking relies on both individual reputation
and social relationship to compute the trust value. NodeRanking evaluates reputation using local information. A node's reputation value can be readily determined by the number of references from other nodes in the network. These adapted algorithms are capable of handling a huge number of nodes disseminated in different rings, which improves complexity and reduces the number of malicious nodes in a hierarchical context. Furthermore, we describe the components of the hierarchical model architecture and present and discuss the results from the experiments. These experiments are employed to verify and compare reduction of downloads from malicious peers, load distribution and residual curl in at structured networks and in hierarchically structured networks.
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Ekonomická analýza podniku KK Technoing, spol.s r.o. / Economic analysis of KK TECHNOING co., Ltd.Kovařík, Jakub January 2014 (has links)
This diploma thesis comprehensively analyzes the economic situation of a family-owned business, KK TECHNOING Co., Ltd, between 2010 and 2014. The analysis focuses specifically on quantifying the economic benefits generated for the businesses' owners. The theory of the thesis, including an introduction to the methodological apparatus applied in the analytical portion of the thesis, is presented after the foreword. The analytical portion is located after a short introduction to KK TECHNOING. The practical part of the economic analysis includes a horizontal and vertical analysis of the company's financial statements, ratios parallel system, the DuPont and the Economic value added analysis, creditworthy and bankruptcy models and a business sector comparison. All findings will be summarized and evaluated at the end of the thesis with specific suggestions for company improvement.
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Does Jealousy of Others Make Us Happy? / Činí nás žárlivost druhých šťasnými?Svatoš, Jiří January 2014 (has links)
The relative income is often cited as a reason why happiness of nations does not grow in time with growing GDP. The study replicates the methodology of several different researchers from basic scatterplots, standard OLS and ordered probit models to hierarchical linear multilevel models (HLM). The results provide evidence that the happiness is actually rising with the growing GDP, although slowly and with the GDP measured in logarithm. On the contrary, the relevance of relative income to happiness is ambiguous through all the proposed models. Furthermore, the individual characteristics like marital status or employment status are proved to explain the differences in happiness much better than income. Finally it is shown that income has similar effects on different measurements of subjective well-being (health, happiness and emotional well-being).
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Shared sovereignty in a two State context : a problem of distributive justiceNunez, Jorge Emilio January 2014 (has links)
Most - if not all - conflicts in international relations have - to an extent - something to do with sovereignty. On the theoretical side, we learn at University that either considered as a strong concept or one that has lost relevance, it is still discussed. On the practical side, the prerogatives a State has over its people and territory appear to be the highest. Within these ideal and real backgrounds, there are various sovereignty disputes around the world that struggle between legal and political limbo, status quo and continuous tension with various negative consequences for all the involved parties (e.g. violation of human rights, war, arms trafficking, only to name a few). It is increasingly clear that the available remedies have been less than successful, and a peaceful and definitive solution is needed. This thesis proposes a fair and just way of dealing with certain sovereignty conflicts. Part One presents the core argument to work out the structure upon which this thesis will be developed. There is a traditional idea that sovereignty must be unshared and unlimited. I argue that in actual fact both in theory and in practice sovereignty is always limited. Thereby, I consider how shared sovereignty is possible—how a State can limit itself and stay sovereign. Chapter One, the Introduction, presents the basic constitutive elements of this thesis. Chapter Two examines if sovereignty can be (in fact, may actually be) limited, and therefore can be shared. To show this I use both criticism of the best known theories of sovereignty and investigation of the historical facts. Part Two explores the minimum elements that must be acknowledged conceptually, legally and realistically in order to give flesh to shared sovereignty and the way it needs to work if we want a peaceful understanding amongst the parties concerned. Chapter Three appraises ‘shared sovereignty’ and similar expressions used in political and legal literature. In order to do that, I show which notions of shared sovereignty are not relevant. Chapter Four examines how a relevant notion can be developed, using the analogy of self-ownership. Chapter Five discusses the main remedies applied at international level in sovereignty issues and why proposed alternatives to shared sovereignty will not solve the problem. Part Three considers how distributive justice theories can be in tune with the concept of sovereignty and explores the possibility of a solution for sovereignty conflicts. I argue that shared sovereignty can be that solution based on Rawlsian principles. Chapter Six introduces and explores a new conception of shared sovereignty. Chapter Seven evaluates what sorts of institutions and arrangements could, and would best, realise shared sovereignty so defined by showing in outline how it might be applied to territory, population, government and law. Chapter Eight brings together the main points of this thesis, and shows possible further implications.
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Grothendieck's dessins d'enfants and the combinatorics of Coxeter groupsMalic, Goran January 2015 (has links)
In this thesis we study the properties of Lagrangian matroids of dessins d'enfants (also known as maps on orientable surfaces) and their behaviour under the action of the absolute Galois group Gal(Q). We show that while the Lagrangian matroid of a dessin itself is not invariant under this action, some of its properties, namely its width and parity, are. We also study the partial duals of a dessin and their Lagrangian matroids and show that certain partial duals can always be defined over their field of moduli. We prove some results on the representations of Lagrangian matroids as well. A relationship between dessins, their partial duals and tropical curves arising from monodromy groups of dessins is observed.
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Finanční analýza podniku / Financial Analysis of an EnterpriseTýčová, Miloslava January 2012 (has links)
The content of this thesis is to evaluate the financial situation of the company VARIEL, using methods of financial analysis and comparison with the relevant standards.
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