Dissertations / Theses on the topic 'Finite State Airload Theory'
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Merryman, William Patrick. "Animating the conversion of nondeterministic finite state automata to deterministic finite state automata." Thesis, Montana State University, 2007. http://etd.lib.montana.edu/etd/2007/merryman/MerrymanW0507.pdf.
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Yap, Ngee Thai. "Modeling syllable theory with finite-state transducers." Access to citation, abstract and download form provided by ProQuest Information and Learning Company; downloadable PDF file, 279 p, 2006. http://proquest.umi.com/pqdweb?did=1179954391&sid=4&Fmt=2&clientId=8331&RQT=309&VName=PQD.
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Liu, Jiuling. "A finite state machine synthesizer." PDXScholar, 1989. https://pdxscholar.library.pdx.edu/open_access_etds/3912.
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This thesis presents a Finite State Machine (FSM) Synthesizer developed at Portland State University. The synthesizer starts from a high level behavioral description, in which no states are specified, and generates the lower level FSM descriptions for simulation and physical layout generation.
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Zhao, William Yue. "A new approach to state minimization of finite state machines." PDXScholar, 1989. https://pdxscholar.library.pdx.edu/open_access_etds/3951.
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A complete program to ease the task of large scale Finite State Machine (FSM) minimization presented in this thesis: TDFM (Two Dimensional FSM Minimizer), is a part of the DIADES system. DIADES is an Automatic Design Synthesis System whose development in the Department of Electrical Engineering at Portland State University is supported in part by a research grant from SHARP Microelectronics Technology.
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Kshatriya, Jagannath Rajini Singh. "Visualizing the minimization of a deterministic finite state automaton." Thesis, Montana State University, 2007. http://etd.lib.montana.edu/etd/2007/kshatriyajagannath/KshatriyaJagannathR1207.pdf.
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Hayashi, Masahito. "Asymptotic estimation theory for a finite dimensional pure state model." 京都大学 (Kyoto University), 1999. http://hdl.handle.net/2433/181932.
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Wang, Suning. "Classical and logic based control theory for finite state machines." Thesis, McGill University, 1991. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=70243.
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This thesis formulates the state estimation and control problem for partially observed finite machines in terms of classical and logic-based approaches. First, in Part I, we present a set operation based formulation of an observer (tree) and a dynamic programming based controller. Then we provide the results of computational complexity of building and running such classical observer and controllers. In Part II, we introduce a notion of a logic-based dynamical system, a new paradigm for controlling finite machines. In particular, we give concepts of a logic-based dynamic observer, and a logic-based dynamic controller and demonstrate an equivalence between classical and logic-based systems. Then we introduce a conditional observer and controller logic--COCOLOG for finite machines, which consists of a family of first order logics each corresponding to a node in the observer tree. Conditional control statements are formulated so that (closed loop) control actions occur when specified past measurable (i.e. past observation dependent) conditions are fulfilled. A semantics is supplied for each COCOLOG in terms of interpretations of controlled transitions on a tree of state estimate sets indexed by observation o(k). Consistency and completeness of the first order theories in a COCOLOG family are established. Furthermore, through a certain unique model property, we obtain the decidability result for each logical theory in a COCOLOG family. Last, in Part III, a function evaluation based resolution for COCOLOG theorems, called FE-resolution, is presented. Completeness results for the FE-resolution method is given in terms of relative truthfulness and validity.
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Mason, Kahn. "Notes on the parallel decomposition theory of finite state machines." Thesis, University of Canterbury. Computer Science, 1998. http://hdl.handle.net/10092/8419.
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We extend existing theory for the parallel decomposition of finite machines (finite automata) to ω-machines and timed machines. The focus for all three is the existence of a structural relationship between the decomposition and the original machine. This is defined in terms of suitable homomorphisms. The homomorphisms also yield inuitively obvious relationships between the languages of accepted words.
The theory of decomposition by state partitions obtaining quotient machines is known for finite machines [Hol82, Shi87]. The extensions to ω-machines is straightforward with a suitable choice of acceptance criteria. Muller acceptance criteria [Tho90] seem natural and are used here. A suitable partial order on the partitions leads to a lattice, the minimal elements of which are the natural starting points in locating decompositions.
The extension to timed machines [AD94] is not as straightforward. As anticipated clock resetting and constraints prevent a straightforward state based generalisation. Suitable partitions of both states and clocks are required to generate quotient machines. Once again, a suitable partial order leads to a regarding a lattice, the minimal elements of which are natural starting points. The members of the lattice are now pairs of state partitions with clock subsets.
Each of the theories is developed alongside a worked example illustrating how the theory is applied. Discussion of the results, their potential applications and areas of concern is interleaved with the results, and is summarised at the end.
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Cazalis, Daniel S. "Algebraic Theory of Minimal Nondeterministic Finite Automata with Applications." FIU Digital Commons, 2007. http://digitalcommons.fiu.edu/etd/8.
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Since the 1950s, the theory of deterministic and nondeterministic finite automata (DFAs and NFAs, respectively) has been a cornerstone of theoretical computer science. In this dissertation, our main object of study is minimal NFAs. In contrast with minimal DFAs, minimal NFAs are computationally challenging: first, there can be more than one minimal NFA recognizing a given language; second, the problem of converting an NFA to a minimal equivalent NFA is NP-hard, even for NFAs over a unary alphabet. Our study is based on the development of two main theories, inductive bases and partials, which in combination form the foundation for an incremental algorithm, ibas, to find minimal NFAs. An inductive basis is a collection of languages with the property that it can generate (through union) each of the left quotients of its elements. We prove a fundamental characterization theorem which says that a language can be recognized by an n-state NFA if and only if it can be generated by an n-element inductive basis. A partial is an incompletely-specified language. We say that an NFA recognizes a partial if its language extends the partial, meaning that the NFA's behavior is unconstrained on unspecified strings; it follows that a minimal NFA for a partial is also minimal for its language. We therefore direct our attention to minimal NFAs recognizing a given partial. Combining inductive bases and partials, we generalize our characterization theorem, showing that a partial can be recognized by an n-state NFA if and only if it can be generated by an n-element partial inductive basis. We apply our theory to develop and implement ibas, an incremental algorithm that finds minimal partial inductive bases generating a given partial. In the case of unary languages, ibas can often find minimal NFAs of up to 10 states in about an hour of computing time; with brute-force search this would require many trillions of years.
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Mogliacci, Sylvain [Verfasser]. "Probing the finite density equation of state of QCD via resummed perturbation theory / Sylvain Mogliacci." Bielefeld : Universitätsbibliothek Bielefeld, 2014. http://d-nb.info/1053467508/34.
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Khemuka, Atul Ravi. "Workflow Modeling Using Finite Automata." [Tampa, Fla.] : University of South Florida, 2003. http://purl.fcla.edu/fcla/etd/SFE0000172.
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Marwah, Gaurav. "Algorithms for stochastic finite memory control of partially observable systems." Master's thesis, Mississippi State : Mississippi State University, 2005. http://library.msstate.edu/etd/show.asp?etd=etd-07082005-132056.
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Shin, Dong-Ryeol. "Optimal control of a finite state markov process under counting observation and applications to integrated networks." Diss., Georgia Institute of Technology, 1992. http://hdl.handle.net/1853/13081.
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Druma, Calin. "Formulation of steady-state and transient potential problems using boundary elements." Ohio : Ohio University, 1999. http://www.ohiolink.edu/etd/view.cgi?ohiou1175886094.
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Pelino, Guglielmo. "Topics in finite state mean field games and non-Markovian interacting spin systems." Doctoral thesis, Università degli studi di Padova, 2019. http://hdl.handle.net/11577/3422695.
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This Dissertation is devoted to the study of large stochastic systems of small interacting individuals and their macroscopic limit formulations, under symmetric properties of the interactions.
The examples we consider belong to two separate contexts, depending on whether the individuals can control their dynamics or not.
In the first case, treated in Part 1, we fall into the framework of N-player and mean field games, while in the latter, analyzed in Part 2, the resulting models are examples of interacting particle systems.
More specifically, in the first part (Chapters 1-2) we focus on the convergence problem in mean field games, i.e. on the rigorous justification of mean field games as limits, when the number of players tends to infinity, of Nash equilibria of symmetric non-zero sum non-cooperative N-player games. In particular, we study finite state mean field games, where the state of each player belongs to a discrete finite space, analyzing separately the uniqueness case (Chapter 1) and a scenario with non-uniqueness of solutions to the mean field game (Chapter 2).
In the second part of the Dissertation (Chapters 3-4) we study some examples of interacting spin systems, with non-Markovian individual dynamics, arising as proper modifications of classical ferromagnetic mean field spin systems dynamics. In particular, we focus on two mechanisms for relaxing the Markovianity: a state augmentation procedure, and the insertion of memory effects in the evolution.
While one of the goals is still to rigorously justify the passage to a macroscopic description, the models of Part 2 present some features of independent interest, including phase transitions (Chapters 3-4), the emergence of self-sustained oscillations (Chapter 3), and the presence of multiple spatio-temporal scales phenomena (Chapter 4).
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Calzolari, Francesco. "Second quantization theory for many-particles stochastic dynamics on finite transport and storage capacity network." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2017. http://amslaurea.unibo.it/13553/.
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Nella tesi viene studiato il random walk di particelle non interagenti su network con capacità di trasporto e capienza dei nodi finite. L’argomento viene affrontato introducendo per il sistema un formalismo di seconda quantizzazione. Dopo avere dimostrato l'effettiva conservazione del numero totale di particelle e che per il sistema vale una relazione di bilancio dettagliato, vengono derivate le relazioni di Onsager per il caso di un network con capacità di trasporto finita. Infine, viene ricavata l'espressione esplicita della distribuzione stazionaria di probabilità per il caso di un network con capienza finita per nodo.
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Wu, Zhibo. "Equation of state for polytetrafluoroethylene (PTFE) and mixtures with PTFE." Diss., Atlanta, Ga. : Georgia Institute of Technology, 2009. http://hdl.handle.net/1853/29696.
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Thesis (Ph.D)--Aerospace Engineering, Georgia Institute of Technology, 2009.Committee Chair: Hanagud,Sathya; Committee Member: Apetre, Nicoleta; Committee Member: Kardomateas, George; Committee Member: McDowell, David L.; Committee Member: Ruzzene, Massimo. Part of the SMARTech Electronic Thesis and Dissertation Collection.
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Adedoyin, Adetokunbo Adelana. "Determination of best practice guidelines for performing large eddy simulation of flows in configurations of engineering interest." Master's thesis, Mississippi State : Mississippi State University, 2007. http://library.msstate.edu/etd/show.asp?etd=etd-06222007-140721.
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Nikolic, Aleksandar. "The physics of multilayer topological insulator heterostructures using low-energy models." Thesis, University of Cambridge, 2018. https://www.repository.cam.ac.uk/handle/1810/283001.
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This thesis studies the physics of multilayer heterostructures grown from topological insulators (TIs), primarily bismuth selenide and antimony telluride, and other topologically trivial materials. This is done by extending a standard low-energy 3D TI Hamiltonian and varying its associated material parameters across the simulation domain. New results arising from the position-dependent TI interface model are found. For the first time, this method is incorporated into a density-functional theory (DFT) solver in order to study the self-consistent charge density in multilayer TI heterostructures due to the interface states. The thesis is structured as follows. The introduction (Ch. 1) presents a pedagogical review of the theory of 3D TIs and low-energy Hamiltonians used to study them, as well as typical methods in solid state physics that are made use of throughout the thesis. Chapter 2 presents the position-dependent Hamiltonian, showing new evidence for topological features of bulk states including varying degrees of band mixing and inversion; also, interface state tunnelling is shown to be affected by atomic layer orbital overlap, and incomplete localisation of surface states is demonstrated for antimony telluride. Chapter 3 presents a new DFT model of TI heterostructure interfaces and shows how conduction through TI interface states can be controlled with an electric field. Chapter 4 covers the extension of the model in Ch. 1 to 2D cross-sections of TI wires and heterostructures, showing for the first time evidence of localisation of conduction almost entirely within the inner interfaces of a 2D heterostructure wire. Chapter 5 presents our work with magnetic fields, demonstrating evolution of interface and bulk states with changing magnetic field and Landau level, as well as presenting new evidence for more complex spin structures in bismuth selenide arising from Landé factor signs. Our conclusions are presented in Chapter 6.
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Müller, Tobias [Verfasser]. "A new perspective to strongly-interacting lattice fermions in the framework of density functional theory : from ground-state correlations to spin-charge separation at finite temperatures / Tobias Müller." Kassel : Universitätsbibliothek Kassel, 2021. http://d-nb.info/123338113X/34.
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Saers, Markus. "Translation as Linear Transduction : Models and Algorithms for Efficient Learning in Statistical Machine Translation." Doctoral thesis, Uppsala universitet, Institutionen för lingvistik och filologi, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-135704.
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Automatic translation has seen tremendous progress in recent years, mainly thanks to statistical methods applied to large parallel corpora. Transductions represent a principled approach to modeling translation, but existing transduction classes are either not expressive enough to capture structural regularities between natural languages or too complex to support efficient statistical induction on a large scale. A common approach is to severely prune search over a relatively unrestricted space of transduction grammars. These restrictions are often applied at different stages in a pipeline, with the obvious drawback of committing to irrevocable decisions that should not have been made. In this thesis we will instead restrict the space of transduction grammars to a space that is less expressive, but can be efficiently searched. First, the class of linear transductions is defined and characterized. They are generated by linear transduction grammars, which represent the natural bilingual case of linear grammars, as well as the natural linear case of inversion transduction grammars (and higher order syntax-directed transduction grammars). They are recognized by zipper finite-state transducers, which are equivalent to finite-state automata with four tapes. By allowing this extra dimensionality, linear transductions can represent alignments that finite-state transductions cannot, and by keeping the mechanism free of auxiliary storage, they become much more efficient than inversion transductions. Secondly, we present an algorithm for parsing with linear transduction grammars that allows pruning. The pruning scheme imposes no restrictions a priori, but guides the search to potentially interesting parts of the search space in an informed and dynamic way. Being able to parse efficiently allows learning of stochastic linear transduction grammars through expectation maximization. All the above work would be for naught if linear transductions were too poor a reflection of the actual transduction between natural languages. We test this empirically by building systems based on the alignments imposed by the learned grammars. The conclusion is that stochastic linear inversion transduction grammars learned from observed data stand up well to the state of the art.
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Angus, Simon Douglas Economics Australian School of Business UNSW. "Economic networks: communication, cooperation & complexity." Awarded by:University of New South Wales. Economics, 2007. http://handle.unsw.edu.au/1959.4/27005.
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This thesis is concerned with the analysis of economic network formation. There are three novel sections to this thesis (Chapters 5, 6 and 8). In the first, the non-cooperative communication network formation model of Bala and Goyal (2000) (BG) is re-assessed under conditions of no inertia. It is found that the Strict Nash circle (or wheel) structure is still the equilibrium outcome for n = 3 under no inertia. However, a counter-example for n = 4 shows that with no inertia infinite cycles are possible, and hence the system does not converge. In fact, cycles are found to quickly dominate outcomes for n > 4 and further numerical simulations of conditions approximating no inertia (probability of updating > 0.8 to 1) indicate that cycles account for a dramatic slowing of convergence times. These results, together with the experimental evidence of Falk and Kosfeld (2003) (FK) motivate the second contribution of this thesis. A novel artificial agent model is constructed that allows for a vast strategy space (including the Best Response) and permits agents to learn from each other as was indicated by the FK results. After calibration, this model replicates many of the FK experimental results and finds that an externality exploiting ratio of benefits and costs (rather than the difference) combined with a simple altruism score is a good proxy for the human objective function. Furthermore, the inequity aversion results of FK are found to arise as an emergent property of the system. The third novel section of this thesis turns to the nature of network formation in a trust-based context. A modified Iterated Prisoners' Dilemma (IPD) model is developed which enables agents to play an additional and costly network forming action. Initially, canonical analytical results are obtained despite this modification under uniform (non-local) interactions. However, as agent network decisions are 'turned on' persistent cooperation is observed. Furthermore, in contrast to the vast majority of non-local, or static network models in the literature, it is found that a-periodic, complex dynamics result for the system in the long-run. Subsequent analysis of this regime indicates that the network dynamics have fingerprints of self-organized criticality (SOC). Whilst evidence for SOC is found in many physical systems, such dynamics have been seldom, if ever, reported in the strategic interaction literature.
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Challa, Subhash. "Nonlinear state estimation and filtering with applications to target tracking problems." Thesis, Queensland University of Technology, 1998.
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Newhouse, Jack. "Explorations of the Aldous Order on Representations of the Symmetric Group." Scholarship @ Claremont, 2012. https://scholarship.claremont.edu/hmc_theses/35.
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The Aldous order is an ordering of representations of the symmetric group motivated by the Aldous Conjecture, a conjecture about random processes proved in 2009. In general, the Aldous order is very difficult to compute, and the proper relations have yet to be determined even for small cases. However, by restricting the problem down to Young-Jucys-Murphy elements, the problem becomes explicitly combinatorial. This approach has led to many novel insights, whose proofs are simple and elegant. However, there remain many open questions related to the Aldous Order, both in general and for the Young-Jucys-Murphy elements.
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Gabriel, Naveen. "Automatic Speech Recognition in Somali." Thesis, Linköpings universitet, Statistik och maskininlärning, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-166216.
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The field of speech recognition during the last decade has left the research stage and found its way into the public market, and today, speech recognition software is ubiquitous around us. An automatic speech recognizer understands human speech and represents it as text. Most of the current speech recognition software employs variants of deep neural networks. Before the deep learning era, the hybrid of hidden Markov model and Gaussian mixture model (HMM-GMM) was a popular statistical model to solve speech recognition. In this thesis, automatic speech recognition using HMM-GMM was trained on Somali data which consisted of voice recording and its transcription. HMM-GMM is a hybrid system in which the framework is composed of an acoustic model and a language model. The acoustic model represents the time-variant aspect of the speech signal, and the language model determines how probable is the observed sequence of words. This thesis begins with background about speech recognition. Literature survey covers some of the work that has been done in this field. This thesis evaluates how different language models and discounting methods affect the performance of speech recognition systems. Also, log scores were calculated for the top 5 predicted sentences and confidence measures of pre-dicted sentences. The model was trained on 4.5 hrs of voiced data and its corresponding transcription. It was evaluated on 3 mins of testing data. The performance of the trained model on the test set was good, given that the data was devoid of any background noise and lack of variability. The performance of the model is measured using word error rate(WER) and sentence error rate (SER). The performance of the implemented model is also compared with the results of other research work. This thesis also discusses why log and confidence score of the sentence might not be a good way to measure the performance of the resulting model. It also discusses the shortcoming of the HMM-GMM model, how the existing model can be improved, and different alternatives to solve the problem.
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Бондаренко, Марина Олександрівна. "Забезпечення міцності тонкостінних конструкцій шляхом обґрунтування параметрів із використанням апроксимацій поверхонь відгуку." Thesis, НТУ "ХПІ", 2018. http://repository.kpi.kharkov.ua/handle/KhPI-Press/37533.
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Дисертація на здобуття наукового ступеня кандидата технічних наук за спеціальністю 05.02.09 – динаміка та міцність машин. Національний технічний університет "Харківський політехнічний інститут", Міністерство освіти і науки України, Харків, 2018.
Дисертація присвячена розробці підходу і моделей для забезпечення конструкційної міцності складних тонкостінних машинобудівних конструкцій, що працюють в умовах геометрично та фізично нелінійної поведінки матеріалу, шляхом обґрунтування проектних рішень. Розроблений підхід базується на використанні математичної моделі напружено-деформованого стану з урахуванням геометричної та фізичної нелінійностей, а також – методів апроксимації для побудови функцій, що описують оцінювані характеристики досліджуваного об'єкта. Різні критерії, за якими проводиться пошук проектних рішень (включаючи характеристики міцності, жорсткості, технологічні та економічні чинники), вносяться до цільової функції. У процесі пошуку проектних рішень запропоновано послідовно використовувати апроксимаційні моделі різного ступеня точності. До них застосовується розроблений алгоритм пошуку раціональних параметрів, який враховує особливості форми поверхонь відгуку, що спостерігаються при розв'язанні прикладних задач. Розроблені алгоритми і моделі застосовані для розв'язання тестових та прикладних задач. Зокрема, розроблені рекомендації для каркасу кузова автобуса, вантажного напіввагона, каркасу кабіни трактора, корпусів БТР-80 та тягача МТ-Л. Проведена розрахунково-експериментальна верифікація розроблених скінченно-елементних моделей.The thesis in qualification for a scientific degree of Candidate of Technical Science in speciality 05.02.09 ‒ dynamics and strength of machines, National Technical University "Kharkiv Polytechnical Institute", Kharkiv, 2018. The dissertation deals with the development of approach and models for providing of structural strength of complicated thin-walled machine-building structures, which operate in the conditions of geometric and physical nonlinearities using design solution validation. The developed approach is based on the use of mathematical model for stress-strain state taking into account geometric and physical nonlinearities and methods of approximation for constructing functions describing the evaluated characteristics of the object under study. The various factors behind the search for design solutions (including characteristics of strength, rigidity, technological and economic factors), are being added into this function. During searching for design solutions it is proposed to successively use approximation models of various accuracy degrees. The developed algorithm for rational parameters search, which takes into account the peculiarities of the response surface shape observed in solving applied problems, is applied to them. In this case, the solution is sought over the whole range of parameter changes. Thus, in the search process, global trends of changes in design decisions are taken into account, and not local ones, as in other approaches. This allows obtain a rational solution that is stable to changes in parameters, which are possible in course of design work and production conditions. The developed algorithms and models are used for solving test and applied problems. In particular, recommendations for the body framing of the bus, freight car, the frame of the tractor cabin, the BTR-80 and MT-L hulls are developed. Computational and experimental verification of developed finite-element models was carried out. The research was carried out at three objects: on the upper part of BTR-80 armored personnel carrier mock-up, and on the prototypes of BTR-3E hull and covered railcar. During frequency characteristics studies, the oscillations excitation of the hull mock-up was effected by rubberized drummer influence at certain points of structure. With use of verified finite element models, the BTR-3E hull prototype was investigated. The experimental research technique provided impulsive action on the hull at a number of points, and fixation of time distributions of accelerations at these points by accelerometers. The results difference is in range of 8-12% for frequencies of free oscillations and for damping logarithmic decrement. Computational studies, and then full-scale tests are also subject to the covered railcar prototype made with recommended settings. Average difference for displacement and stress is 15%.
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Бондаренко, Марина Олександрівна. "Забезпечення міцності тонкостінних конструкцій шляхом обґрунтування параметрів із використанням апроксимацій поверхонь відгуку." Thesis, НТУ "ХПІ", 2018. http://repository.kpi.kharkov.ua/handle/KhPI-Press/37536.
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Дисертація на здобуття наукового ступеня кандидата технічних наук за спеціальністю 05.02.09 – динаміка та міцність машин. Національний технічний університет "Харківський політехнічний інститут", Міністерство освіти і науки України, Харків, 2018.
Дисертація присвячена розробці підходу і моделей для забезпечення конструкційної міцності складних тонкостінних машинобудівних конструкцій, що працюють в умовах геометрично та фізично нелінійної поведінки матеріалу, шляхом обґрунтування проектних рішень. Розроблений підхід базується на використанні математичної моделі напружено-деформованого стану з урахуванням геометричної та фізичної нелінійностей, а також – методів апроксимації для побудови функцій, що описують оцінювані характеристики досліджуваного об'єкта. Різні критерії, за якими проводиться пошук проектних рішень (включаючи характеристики міцності, жорсткості, технологічні та економічні чинники), вносяться до цільової функції. У процесі пошуку проектних рішень запропоновано послідовно використовувати апроксимаційні моделі різного ступеня точності. До них застосовується розроблений алгоритм пошуку раціональних параметрів, який враховує особливості форми поверхонь відгуку, що спостерігаються при розв'язанні прикладних задач. Розроблені алгоритми і моделі застосовані для розв'язання тестових та прикладних задач. Зокрема, розроблені рекомендації для каркасу кузова автобуса, вантажного напіввагона, каркасу кабіни трактора, корпусів БТР-80 та тягача МТ-Л. Проведена розрахунково-експериментальна верифікація розроблених скінченно-елементних моделей.The thesis in qualification for a scientific degree of Candidate of Technical Science in speciality 05.02.09 ‒ dynamics and strength of machines, National Technical University "Kharkiv Polytechnical Institute", Kharkiv, 2018. The dissertation deals with the development of approach and models for providing of structural strength of complicated thin-walled machine-building structures, which operate in the conditions of geometric and physical nonlinearities using design solution validation. The developed approach is based on the use of mathematical model for stress-strain state taking into account geometric and physical nonlinearities and methods of approximation for constructing functions describing the evaluated characteristics of the object under study. The various factors behind the search for design solutions (including characteristics of strength, rigidity, technological and economic factors), are being added into this function. During searching for design solutions it is proposed to successively use approximation models of various accuracy degrees. The developed algorithm for rational parameters search, which takes into account the peculiarities of the response surface shape observed in solving applied problems, is applied to them. In this case, the solution is sought over the whole range of parameter changes. Thus, in the search process, global trends of changes in design decisions are taken into account, and not local ones, as in other approaches. This allows obtain a rational solution that is stable to changes in parameters, which are possible in course of design work and production conditions. The developed algorithms and models are used for solving test and applied problems. In particular, recommendations for the body framing of the bus, freight car, the frame of the tractor cabin, the BTR-80 and MT-L hulls are developed. Computational and experimental verification of developed finite-element models was carried out. The research was carried out at three objects: on the upper part of BTR-80 armored personnel carrier mock-up, and on the prototypes of BTR-3E hull and covered railcar. During frequency characteristics studies, the oscillations excitation of the hull mock-up was effected by rubberized drummer influence at certain points of structure. With use of verified finite element models, the BTR-3E hull prototype was investigated. The experimental research technique provided impulsive action on the hull at a number of points, and fixation of time distributions of accelerations at these points by accelerometers. The results difference is in range of 8-12% for frequencies of free oscillations and for damping logarithmic decrement. Computational studies, and then full-scale tests are also subject to the covered railcar prototype made with recommended settings. Average difference for displacement and stress is 15%.
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Атрошенко, Александр Александрович. "Анализ конструкционной прочности составных тонкостенных конструкций с болтовым соединением элементов." Thesis, НТУ "ХПИ", 2016. http://repository.kpi.kharkov.ua/handle/KhPI-Press/21814.
Full textAbstract:
Диссертация на соискание научной степени кандидата технических наук по специальности 05.02.09 – динамика и прочность машин. Национальный технический университет "Харьковский политехнический институт", Министерство образования и науки Украины, Харьков, 2016.
Диссертация посвящена разработке подходов, методов и моделей для исследования конструкционной прочности составных тонкостенных машиностроительных конструкций с болтовым соединением элементов. В работе решена задача анализа напряженно-деформированного состояния составных тонкостенных машиностроительных конструкций с болтовым соединением элементов, а также его реализация и определение закономерностей распределения прогибов, смещений и продольных усилий. Также в данной постановке учитывались следующие важные факторы: зазор в болтовых соединениях, силы трения между контактирующими поверхностями, предварительная затяжка болтовых соединений, наличие уплотнительных шайб состоящих из полимерных материалов, а также учета гофрированной формы применяемых панелей. На основе математических моделей напряженно-деформированного состояния оболочечных, стержневых и пластинчатых конструкций в работе разработана математическая модель, которая учитывает влияние продольных сил и геометрической нелинейности в целом на НДС составленных тонкостенных конструкций. При этом предложена процедура осреднения продольных усилий, действующей в сечении стержня. В результате система связанных дифференциальных уравнения преобразуется к дифференциальному уравнению и интегральному соотношению. Для решения задачи об определении НДС составного стержня выбран метод конечных разностей. Получены результаты решения ряда прикладных задач. Установлены закономерности изменения напряженно-деформированного состояния тонкостенных конструкций на примере металлических бункеров при варьировании проектно-технологических параметров. Экспериментально определен характер поведения системы полос, соединенных болтовым крепежом с зазором, нагруженных равномерно по верхней кромке поперечным циклическим усилием. Проведено сравнение полученных численных результатов исследований с полученными экспериментальными данными. Подтверждено качественное и количественное соответствие результатов численных и экспериментальных исследований изменения прогибов системы полос.Thesis for the degree of Candidate of technical Sciences in specialty 05.02.09 – dynamics and strength of machines. National technical University "Kharkiv Polytechnic Institute", Ministry of Education and Science of Ukraine, Kharkiv, 2016. The thesis is devoted to the development of approaches, methods and models to study structural strength of composite thin-walled engineering structures with bolted elements. This work is solves the problem of analysis of the stress-strain state of composite thin-walled engineering structures with bolted elements, as well as its implementation and determination of the distribution of deflections, displacements and longitudinal efforts. Also in this formulation the following important factors were taken into account: the gap in bolted joints, friction force between the contacting surfaces, the pre-tightening of bolted connections, the presence of polymeric materials, as well as consideration of the corrugated shape of panels used. On the basis of mathematical models of the stress-strain state of the shell, the rod and plate structures, a mathematical model that takes into consideration the influence of axial forces and geometric nonlinearity in general on stress-strain state of composed thin-walled structures was elaborated in this thesis. The results of solving some applied problems were obtained. The regularities of changes of stress-strain state of thin-walled engineering structures at variation of design and process parameters were defined.
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Атрошенко, Олександр Олександрович. "Аналіз конструкційної міцності складених тонкостінних конструкцій з болтовим з'єднанням елементів." Thesis, НТУ "ХПІ", 2016. http://repository.kpi.kharkov.ua/handle/KhPI-Press/21789.
Full textAbstract:
Дисертація на здобуття наукового ступеня кандидата технічних наук за спеціальністю 05.02.09 – динаміка та міцність машин. Національний технічний університет "Харківський політехнічний інститут", Міністерство освіти і науки України, Харків, 2016.
Дисертація присвячена розробці підходів, методів і моделей для дослідження конструкційної міцності складених тонкостінних машинобудівних конструкцій з болтовим з'єднанням елементів. У роботі розв'язана задача аналізу напружено-деформованого стану складених тонкостінних машинобудівних конструкцій з болтовим з'єднанням елементів, а також його реалізація і визначення закономірностей розподілу прогинів, зміщень і поздовжніх зусиль. Також в даній постановці ураховувались наступні важливі чинники: зазор у болтовому з'єднанні, сили тертя між контактуючими поверхнями, попереднє затягуванням болтових з'єднань, наявністю полімерних матеріалів, а також урахування гофрованої форми застосованих панелей. На основі математичних моделей напружено-деформованого стану оболонкових, стрижневих та пластинчатих конструкцій, в роботі розроблена математична модель, яка ураховує вплив поздовжніх сил і геометричної нелінійності в цілому на НДС складених тонкостінних конструкцій. Отримані результати розв'язання низки прикладних задач. Установленні закономірності зміни напружено-деформованого стану тонкостінних машинобудівних конструкцій при варіюванні проектно-технологічних параметрів.Thesis for the degree of Candidate of technical Sciences in specialty 05.02.09 – dynamics and strength of machines. National technical University "Kharkiv Polytechnic Institute", Ministry of Education and Science of Ukraine, Kharkiv, 2016. The thesis is devoted to the development of approaches, methods and models to study structural strength of composite thin-walled engineering structures with bolted elements. This work is solves the problem of analysis of the stress-strain state of composite thin-walled engineering structures with bolted elements, as well as its implementation and determination of the distribution of deflections, displacements and longitudinal efforts. Also in this formulation the following important factors were taken into account: the gap in bolted joints, friction force between the contacting surfaces, the pre-tightening of bolted connections, the presence of polymeric materials, as well as consideration of the corrugated shape of panels used. On the basis of mathematical models of the stress-strain state of the shell, the rod and plate structures, a mathematical model that takes into consideration the influence of axial forces and geometric nonlinearity in general on stress-strain state of composed thin-walled structures was elaborated in this thesis. The results of solving some applied problems were obtained. The regularities of changes of stress-strain state of thin-walled engineering structures at variation of design and process parameters were defined.
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Скрипченко, Наталья Борисовна. "Контактное взаимодействие сложнопрофильных деталей машиностроительных конструкций с учетом локальной податливости поверхностного слоя." Thesis, НТУ "ХПИ", 2015. http://repository.kpi.kharkov.ua/handle/KhPI-Press/19908.
Full textAbstract:
Диссертация на соискание научной степени кандидата технических наук по специальности 05.02.09 – динамика и прочность машин. Национальный технический университет "Харьковский политехнический институт", Министерство образования и наук Украины, Харьков, 2016.
Диссертация посвящена разработке подходов, методов и моделей для исследования напряженно-деформированного состояния сложнопрофильных шероховатых тел с учетом контактного взаимодействия. В работе решена задача анализа контактного взаимодействия сложнопрофильных элементов машиностроительных конструкций с учетом дополнительных факторов влияющих на распределение контактных давлений (учет податливости поверхностного слоя, конечность размеров контактирующих тел). Предложено для анализа контактного взаимодействия сложнопрофильных тел применять вариант метода граничных уравнений, дополненный моделью учета податливости промежуточного слоя. Для моделирования упругого слоя применена модель Винклера. Предложенный метод исследования контактного взаимодействия объединяет в рамках единых соотношений "локальные" и "глобальные" характеристики податливости контактирующих шероховатых тел. Решен ряд прикладных задач анализа контактного взаимодействия, а именно проведено исследование влияния формы зазора и податливости шероховатого слоя на характер распределений контактных давлений, проведено исследование контактного взаимодействия прямоугольного в плане штампа со скруглениями, решена задача контакта подшипника качения с модифицированным двурадиусным роликом, проведен анализ взаимодействия шаровых поршней с беговыми дорожками гидрообъмной передачи танковой трансмиссии. Во время выполнения работы проведен ряд экспериментальных исследований для анализа контактного взаимодействия сложнопрофильных элементов машиностроительных конструкций с учетом податливости шероховатого слоя. Для исследования контактных давлений задействована технология контактных отпечатков с использованием чувствительных пленок. Проведено сравнение полученных численных результатов исследований с полученными экспериментальными данными. Подтверждена точность и достоверность предложенных методов и моделей, а также созданного программно-модельного комплекса.The thesis in qualification for a scientific degree of Candidate of Technical Science in speciality 05.02.09 - dynamics and strength of machines, National Technical University "Kharkiv Polytechnical Institute", Kharkiv, 2016. The thesis is devoted to development of approaches, methods and models for analysis of stress-strain state of complex-shaped bodies with account for their contact over rough surfaces. In the present work the contact problem is solved for complex-shaped elements of engineering structures with local compliance of the surface layer. For this purpose a variation to the boundary integral equations method extended with a Winkler-type model of elastic layer is proposed. The resulting approach combines in a unified formulation the "local" and "global" compliance characteristics of the contacting rough bodies. The numerical implementation of the boundary element method is included in a software-and-model complex for analysis of contact interaction of complex-shaped bodies. A number of applied contact problems is solved. Namely, the influence of the gap and rough layer compliance on the contact pressure distribution is studied for the following cases: contact of a rectangular round-end stamp with a flat surface, junction of a rolling bearing and a modified double-radius roller, normal traction between spherical pistons and treadmills of a tank transmission. Numerical results of the research are compared to experimental data. Accuracy and reliability of the proposed methods and models, as well as special-purpose software-andmodel complex are confirmed.
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Скріпченко, Наталія Борисівна. "Контактна взаємодія складнопрофільних деталей машинобудівних конструкцій з урахуванням локальної податливості поверхневого шару." Thesis, ФО-П Дуюнова Т. В, 2016. http://repository.kpi.kharkov.ua/handle/KhPI-Press/19907.
Full textAbstract:
Дисертація на здобуття наукового ступеня кандидата технічних наук за спеціальністю 05.02.09 – динаміка та міцність машин. Національний технічний університет "Харківський політехнічний інститут", Міністерство освіти і науки України, Харків, 2016.
Дисертація присвячена розробці підходів, методів і моделей для дослідження напружено-деформованого стану складнопрофільних тіл з урахуванням їхнього контакту по шорстких поверхнях. У роботі розв'язана задача аналізу контактної взаємодії складнопрофільних елементів машинобудівних конструкцій за наявності локальної податливості поверхневого шару. Для цього запропоновано варіант методу граничних рівнянь, в який додана модель пружного проміжного шару за Вінклером. Отриманий метод дослідження контактної взаємодії об'єднує в рамках єдиних співвідношень "локальні" та "глобальні" характеристики податливості контактуючих шорстких тіл. Числова реалізація методу граничних елементів здійснена в спеціалізованому програмно-модельному комплексі для дослідження контактної взаємодії складнопрофільних тіл. Розв'язано низку прикладних задач аналізу контактної взаємодії, а саме проведено дослідження впливу форми зазору і податливості шорсткого шару на характер розподілів контактного тиску у наступних випадках: контакту прямокутного в плані штампа з округленнями з плоскою поверхнею, спряження підшипника кочення з модифікованим дворадіусним роликом, передачі зусиль між кульовими поршнями та біговими доріжками в гідрооб'ємній передачі танкової трансмісії. Проведене порівняння отриманих числових результатів досліджень з експериментальними даними. Підтверджено точність і достовірність запропонованих методів та моделей, а також створеного програмно-модельного комплексу.The thesis in qualification for a scientific degree of Candidate of Technical Science in speciality 05.02.09 - dynamics and strength of machines, National Technical University "Kharkiv Polytechnical Institute", Kharkiv, 2016. The thesis is devoted to development of approaches, methods and models for analysis of stress-strain state of complex-shaped bodies with account for their contact over rough surfaces. In the present work the contact problem is solved for complex-shaped elements of engineering structures with local compliance of the surface layer. For this purpose a variation to the boundary integral equations method extended with a Winkler-type model of elastic layer is proposed. The resulting approach combines in a unified formulation the "local" and "global" compliance characteristics of the contacting rough bodies. The numerical implementation of the boundary element method is included in a software-and-model complex for analysis of contact interaction of complex-shaped bodies. A number of applied contact problems is solved. Namely, the influence of the gap and rough layer compliance on the contact pressure distribution is studied for the following cases: contact of a rectangular round-end stamp with a flat surface, junction of a rolling bearing and a modified double-radius roller, normal traction between spherical pistons and treadmills of a tank transmission. Numerical results of the research are compared to experimental data. Accuracy and reliability of the proposed methods and models, as well as special-purpose software-andmodel complex are confirmed.
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"Parental finite state vector quantizer and vector wavelet transform-linear predictive coding." 1998. http://library.cuhk.edu.hk/record=b5889548.
Full textAbstract:
by Lam Chi Wah.Thesis submitted in: December 1997.
Thesis (M.Phil.)--Chinese University of Hong Kong, 1998.
Includes bibliographical references (leaves 89-91).
Abstract also in Chinese.
Chapter Chapter 1 --- Introduction to Data Compression and Image Coding --- p.1
Chapter 1.1 --- Introduction --- p.1
Chapter 1.2 --- Fundamental Principle of Data Compression --- p.2
Chapter 1.3 --- Some Data Compression Algorithms --- p.3
Chapter 1.4 --- Image Coding Overview --- p.4
Chapter 1.5 --- Image Transformation --- p.5
Chapter 1.6 --- Quantization --- p.7
Chapter 1.7 --- Lossless Coding --- p.8
Chapter Chapter 2 --- Subband Coding and Wavelet Transform --- p.9
Chapter 2.1 --- Subband Coding Principle --- p.9
Chapter 2.2 --- Perfect Reconstruction --- p.11
Chapter 2.3 --- Multi-Channel System --- p.13
Chapter 2.4 --- Discrete Wavelet Transform --- p.13
Chapter Chapter 3 --- Vector Quantization (VQ) --- p.16
Chapter 3.1 --- Introduction --- p.16
Chapter 3.2 --- Basic Vector Quantization Procedure --- p.17
Chapter 3.3 --- Codebook Searching and the LBG Algorithm --- p.18
Chapter 3.3.1 --- Codebook --- p.18
Chapter 3.3.2 --- LBG Algorithm --- p.19
Chapter 3.4 --- Problem of VQ and Variations of VQ --- p.21
Chapter 3.4.1 --- Classified VQ (CVQ) --- p.22
Chapter 3.4.2 --- Finite State VQ (FSVQ) --- p.23
Chapter 3.5 --- Vector Quantization on Wavelet Coefficients --- p.24
Chapter Chapter 4 --- Vector Wavelet Transform-Linear Predictor Coding --- p.26
Chapter 4.1 --- Image Coding Using Wavelet Transform with Vector Quantization --- p.26
Chapter 4.1.1 --- Future Standard --- p.26
Chapter 4.1.2 --- Drawback of DCT --- p.27
Chapter 4.1.3 --- "Wavelet Coding and VQ, the Future Trend" --- p.28
Chapter 4.2 --- Mismatch between Scalar Transformation and VQ --- p.29
Chapter 4.3 --- Vector Wavelet Transform (VWT) --- p.30
Chapter 4.4 --- Example of Vector Wavelet Transform --- p.34
Chapter 4.5 --- Vector Wavelet Transform - Linear Predictive Coding (VWT-LPC) --- p.36
Chapter 4.6 --- An Example of VWT-LPC --- p.38
Chapter Chapter 5 --- Vector Quantizaton with Inter-band Bit Allocation (IBBA) --- p.40
Chapter 5.1 --- Bit Allocation Problem --- p.40
Chapter 5.2 --- Bit Allocation for Wavelet Subband Vector Quantizer --- p.42
Chapter 5.2.1 --- Multiple Codebooks --- p.42
Chapter 5.2.2 --- Inter-band Bit Allocation (IBBA) --- p.42
Chapter Chapter 6 --- Parental Finite State Vector Quantizers (PFSVQ) --- p.45
Chapter 6.1 --- Introduction --- p.45
Chapter 6.2 --- Parent-Child Relationship Between Subbands --- p.46
Chapter 6.3 --- Wavelet Subband Vector Structures for VQ --- p.48
Chapter 6.3.1 --- VQ on Separate Bands --- p.48
Chapter 6.3.2 --- InterBand Information for Intraband Vectors --- p.49
Chapter 6.3.3 --- Cross band Vector Methods --- p.50
Chapter 6.4 --- Parental Finite State Vector Quantization Algorithms --- p.52
Chapter 6.4.1 --- Scheme I: Parental Finite State VQ with Parent Index Equals Child Class Number --- p.52
Chapter 6.4.2 --- Scheme II: Parental Finite State VQ with Parent Index Larger than Child Class Number --- p.55
Chapter Chapter 7 --- Simulation Result --- p.58
Chapter 7.1 --- Introduction --- p.58
Chapter 7.2 --- Simulation Result of Vector Wavelet Transform (VWT) --- p.59
Chapter 7.3 --- Simulation Result of Vector Wavelet Transform - Linear Predictive Coding (VWT-LPC) --- p.61
Chapter 7.3.1 --- First Test --- p.61
Chapter 7.3.2 --- Second Test --- p.61
Chapter 7.3.3 --- Third Test --- p.61
Chapter 7.4 --- Simulation Result of Vector Quantization Using Inter-band Bit Allocation (IBBA) --- p.62
Chapter 7.5 --- Simulation Result of Parental Finite State Vector Quantizers (PFSVQ) --- p.63
Chapter Chapter 8 --- Conclusion --- p.86
REFERENCE --- p.89
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Malik, Tuhin. "Equation of state for dense matter from finite nuclei to neutron star mergers." Doctoral thesis, 2019. http://hdl.handle.net/10316/94981.
Full textAbstract:
Documentos apresentados no âmbito do reconhecimento de graus e diplomas estrangeirosEquation of state (EOS) of dense matter has been constrained from the experimental data available on the properties of finite nuclei and neutron stars. Towards this purpose, a diverse set of nuclear energy density functionals based on relativistic and non-relativistic mean field models have been employed. These EOSs are so chosen that they are consistent with the bulk properties of the finite nuclei. The values of various nuclear matter parameters which predominantly govern the behaviour of the EOS are determined through their correlations with the properties of the neutron stars such as radii, tidal deformability and maximum mass of the neutron stars. The nuclear matter parameters considered are incompressibility, symmetry energy and their density derivatives which appear in the expansion of the EOS around the saturation density. The radii and tidal deformability of the neutron star with the canonical mass display strong correlations with the linear combinations of slopes of the incompressibility and symmetry energy coefficients. Similar correlations with the curvature of the symmetry energy coefficient are also obsvered indicating that the properties of the neutron stars are sensitive to the high density behaviour of the symmetry energy. It is also shown that the giant resonances in nuclei are instrumental in limiting the tidal deformability parameter and the radius of a neutron star in somewhat narrower bounds. The outcomes of the present thesis is important in view of the fact that the accurate values of the various neutron star observables as considered are expected to be available in near future.
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"Finite-state methods and natural language processing : 6th International Workshop, FSMNLP 2007 Potsdam, Germany, september 14 - 16 ; revised papers." Universität Potsdam, 2008. http://opus.kobv.de/ubp/volltexte/2008/2381/.
Full textAbstract:
Proceedings with the revised papers of the FSMNLP (Finite-state Methods and Natural Language Processing) 2007 Workshop in PotsdamTagungsband mit den Beiträgen der FSMNLP (Finite-state Methods and Natural Language Processing) 2007 in Potsdam
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Balasubramanian, Bharath. "Fault tolerance in distributed systems : a coding-theoretic approach." Thesis, 2012. http://hdl.handle.net/2152/ETD-UT-2012-08-5980.
Full textAbstract:
Distributed systems are rapidly increasing in importance due to the need for scalable computations on huge volumes of data. This fact is reflected in many real-world distributed applications such as Amazon's EC2 cloud computing service, Facebook's Cassandra key-value store or Apache's Hadoop MapReduce framework. Multi-core architectures developed by companies such as Intel and AMD have further brought this to prominence, since workloads can now be distributed across many individual cores. The nodes or entities in such systems are often built using commodity hardware and are prone to physical failures and security vulnerabilities. Achieving fault tolerance in such systems is a challenging task, since it is not easy to observe and control these distributed entities. Replication is a standard approach for fault tolerance in distributed systems. The main advantage of this approach is that the backups incur very little overhead in terms of the time taken for normal operation or recovery. However, replication is grossly wasteful in terms of the number of backups required for fault tolerance. The large number of backups has two major implications. First, the total space or memory required for fault tolerance is considerably high. Second, there is a significant cost of resources such as the power required to run the backup processes. Given the large number of distributed servers employed in real-world applications, it is a hard task to provide fault tolerance while achieving both space and operational efficiency. In the world of data fault tolerance and communication, coding theory is used as the space efficient alternate for replication. A direct application of coding theory to distributed servers, treating the servers as blocks of data, is very inefficient in terms of the updates to the backups. This is primarily because each update to the server will affect many blocks in memory, all of which have to be re-encoded at the backups. This leads us to the following thesis statement: Can we design a mechanism for fault tolerance in distributed systems that combines the space efficiency of coding theory with the low operational overhead of replication? We present a new paradigm to solve this problem, broadly referred to as fusion. We provide fusion-based solutions for two models of computation that are representative of a large class of applications: (i) Systems modeled as deterministic finite state machines and, (ii) Systems modeled as programs containing data structures. For finite state machines, we use the notion of Hamming distances to present a polynomial time algorithm to generate efficient backup state machines. For programs hosting data structures, we use a combination of erasure codes and selective replication to generate efficient backups for most commonly used data structures such as queues, array lists, linked lists, vectors and maps. We present theoretical and experimental results that demonstrate the efficiency of our schemes over replication. Finally, we use our schemes to design an efficient solution for fault tolerance in two real-world applications: Amazons Dynamo key-value store, and Google's MapReduce framework.text
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Ang, Thomas. "Problems Related to Shortest Strings in Formal Languages." Thesis, 2010. http://hdl.handle.net/10012/5162.
Full textAbstract:
In formal language theory, studying shortest strings in languages, and variations thereof, can be useful since these strings can serve as small witnesses for properties of the languages, and can also provide bounds for other problems involving languages. For example, the length of the shortest string accepted by a regular language provides a lower bound on the state complexity of the language.
In Chapter 1, we introduce some relevant concepts and notation used in automata and language theory, and we show some basic results concerning the connection between the length of the shortest string and the nondeterministic state complexity of a regular language. Chapter 2 examines the effect of the intersection operation on the length of the shortest string in regular languages. A tight worst-case bound is given for the length of the shortest string in the intersection of two regular languages, and loose bounds are given for two variations on the problem. Chapter 3 discusses languages that are defined over a free group instead of a free monoid. We study the length of the shortest string in a regular language that becomes the empty string in the free group, and a variety of bounds are given for different cases. Chapter 4 mentions open problems and some interesting observations that were made while studying two of the problems: finding good bounds on the length of the shortest squarefree string accepted by a deterministic finite automaton, and finding an efficient way to check if a finite set of finite words generates the free monoid.
Some of the results in this thesis have appeared in work that the author has participated in \cite{AngPigRamSha,AngShallit}.