Thèses : « PARTIAL COMPLETION »

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Easton, Todd William. « On partial completion problems ». Diss., Georgia Institute of Technology, 1999. http://hdl.handle.net/1853/25478.

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Bakonyi, M. (Mihaly). « Completion of partial operator matrices ». W&M ScholarWorks, 1992. https://scholarworks.wm.edu/etd/1539623821.

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This work concerns completion problems for partial operator matrices. A partial matrix is an m-by-n array in which some entries are specified and the remaining are unspecified. We allow the entries to be operators acting between corresponding vector spaces (in general, bounded linear operators between Hilbert spaces). Graphs are associated with partial matrices. Chordal graphs and directed graphs with a perfect edge elimination scheme play a key role in our considerations. A specific choice for the unspecified entries is referred to as a completion of the partial matrix. The completion problems studied here involve properties such as: zero-blocks in certain positions of the inverse, positive (semi)definitness, contractivity, or minimum negative inertia for Hermitian operator matrices. Some completion results are generalized to the case of combinatorially nonsymmetric partial matrices. Several applications including a "maximum entropy" result and determinant formulae for matrices with sparse inverses are given.;In Chapter II we treat completion problems involving zero-blocks in the inverse. Our main result deals with partial operator matrices R, for which the directed graph is associated with an oriented tree. We prove that under invertibility conditions on certain principal minors, R admits a unique invertible completion F such that {dollar}(F\sp{lcub}-1{rcub})\sb{lcub}ij{rcub}{dollar} = 0 whenever {dollar}R\sb{lcub}ij{rcub}{dollar} is unspecified.;Chapter III treats positive semidefinite and Hermitian completions. In the case of partial positive operator matrices with a chordal graph, a "maximum entropy" principle is presented, generalizing the maximum determinant result in the scalar case. We obtain a linear fractional transform parametrization for the set of all positive semidefinite completions for a generalized banded partial matrix. We also give an inertia formula for Hermitian operator matrices with sparse inverses.;In Chapter IV prior results are applied to obtain facts about contractive and linearly constrained completion problems. The solution to a general n-by-n "strong-Parrott" type completion problem is the main result. We prove necessary and sufficient conditions for the existence of a solution as well as a cascade transform parametrization for the set of all solutions.;Chapter V extends the results in Chapter II and III to prove determinant formulae for matrices with sparse inverses. Several ideas from graph theory are used. An inheritance principle for chordal graphs is also presented.

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KUMARI, POONAM. « IN PARTIAL COMPLETION OF REQUIREMENT SUBMITTED FOR THE AWARD ». Thesis, DELHI TECHNOLOGICAL UNIVERSITY, 2021. http://dspace.dtu.ac.in:8080/jspui/handle/repository/18789.

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Boundary Element Method progress into research foR study pile groups. This method including the non-linear conduct of the soil by a hyperbolic modulus reduction curve; the non-linear response of rc pile section. The non- linear behaviour of soil is modelled using a hyperbolic modulus reduction curve; the non-linear response of rcc pile sections is modelled using a hyperbolic modulus reduction curve, also considering tension stiffening's impact; and the effect of suction is modelled using rising the stiffness of shallow portions of soil. The pile group shadowing effect was analysed by a method comparable to that suggested in the Strain Wedge Model for pile group studies.In comparison to more complicated codes like VERSAT-P3D, PLAXIS 3D, and FLAC-3D, the suggested BEM approach requires less computing effort and produces accurate results utilising data from a normal site inquiry. A study of measured and calculated result for a horizontal loaded fixed-head pile group made up of rcc bored piles is provided . The findings of the recommended approach are found to be quite similar to those obtained in the field. To determine the ultimate lateral capacity and deflection under working loads, all tests were carried out to failure. When compared to straight shaft piles , test findings show a non linear response, a significant increase in lateral capacity, and a reduction in deflections at working loads .

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Van, der Walt Jan Harm. « Generalized solutions of systems of nonlinear partial differential equations ». Thesis, Pretoria : [s.n.], 2009. http://upetd.up.ac.za/thesis/available/etd-05242009-122628.

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Grout, Jason Nicholas. « Ultraconnected and Critical Graphs ». BYU ScholarsArchive, 2004. https://scholarsarchive.byu.edu/etd/34.

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We investigate the ultraconnectivity condition on graphs, and provide further connections between critical and ultraconnected graphs in the positive definite partial matrix completion problem. We completely characterize when the join of graphs is ultraconnected, and prove that ultraconnectivity is preserved by Cartesian products. We completely characterize when adding a vertex to an ultraconnected graph preserves ultraconnectivity. We also derive bounds on the number of vertices which guarantee ultraconnectivity of certain classes of regular graphs. We give results from our exhaustive enumeration of ultraconnected graphs up to 11 vertices. Using techniques involving the Lovász theta parameter for graphs, we prove certain classes of graphs are critical (and hence ultraconnected) in the positive definite partial matrix completion problem.

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Kreuger, Per. « Computational Issues in Calculi of Partial Inductive Definitions ». Doctoral thesis, Decisions, Networks and Analytics lab, 1995. http://urn.kb.se/resolve?urn=urn:nbn:se:ri:diva-21196.

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We study the properties of a number of algorithms proposed to explore the computational space generated by a very simple and general idea: the notion of a mathematical definition and a number of suggested formal interpretations ofthis idea. Theories of partial inductive definitions (PID) constitute a class of logics based on the notion of an inductive definition. Formal systems based on this notion can be used to generalize Horn-logic and naturally allow and suggest extensions which differ in interesting ways from generalizations based on first order predicate calculus. E.g. the notion of completion generated by a calculus of PID and the resulting notion of negation is completely natural and does not require externally motivated procedures such as "negation as failure". For this reason, computational issues arising in these calculi deserve closer inspection. This work discuss a number of finitary theories of PID and analyzethe algorithmic and semantical issues that arise in each of them. There has been significant work on implementing logic programming languages in this setting and we briefly present the programming language and knowledge modelling tool GCLA II in which many of the computational prob-lems discussed arise naturally in practice.

Also published as SICS Dissertation no. SICS-D-19

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Edmunds, Hannah. « Perversion of the reel : a thesis presented in partial fulfilment of the requirements for the completion of Master of Fine Arts at Massey University, Wellington, New Zealand ». Massey University, 2010. http://hdl.handle.net/10179/1271.

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Through the use of masculinity as a visual language this research aims to unravel the divide between the role of the act and the acted. French actor Julien Boisselier operates as the male manifestation of the actor in question and functions on multiple levels of performance, both as male and as an actor. Boisseliers depictions of major, medium and minor acted characters offer another level to the performance variable. The aim to highlight the visible triggers of a ‘pure performance’ (a performance where the actor may slip or falter out of acted character and into default human performance) as shown through the choreography of his physiognomy is the experience underpinning this thesis.

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Callow, Glenn. « Extending relational model transformations to better support the verification of increasingly autonomous systems ». Thesis, Loughborough University, 2013. https://dspace.lboro.ac.uk/2134/13435.

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Over the past decade the capabilities of autonomous systems have been steadily increasing. Unmanned systems are moving from systems that are predominantly remotely operated, to systems that include a basic decision making capability. This is a trend that is expected to continue with autonomous systems making decisions in increasingly complex environments, based on more abstract, higher-level missions and goals. These changes have significant implications for how these systems should be designed and engineered. Indeed, as the goals and tasks these systems are to achieve become more abstract, and the environments they operate in become more complex, are current approaches to verification and validation sufficient? Domain Specific Modelling is a key technology for the verification of autonomous systems. Verifying these systems will ultimately involve understanding a significant number of domains. This includes goals/tasks, environments, systems functions and their associated performance. Relational Model Transformations provide a means to utilise, combine and check models for consistency across these domains. In this thesis an approach that utilises relational model transformation technologies for systems verification, Systems MDD, is presented along with the results of a series of trials conducted with an existing relational model transformation language (QVT-Relations). These trials identified a number of problems with existing model transformation languages, including poorly or loosely defined semantics, differing interpretations of specifications across different tools and the lack of a guarantee that a model transformation would generate a model that was compliant with its associated meta-model. To address these problems, two related solvers were developed to assist with realising the Systems MDD approach. The first solver, MMCS, is concerned with partial model completion, where a partial model is defined as a model that does not fully conform with its associated meta-model. It identifies appropriate modifications to be made to a partial model in order to bring it into full compliance. The second solver, TMPT, is a relational model transformation engine that prioritises target models. It considers multiple interpretations of a relational transformation specification, chooses an interpretation that results in a compliant target model (if one exists) and, optionally, maximises some other attribute associated with the model. A series of experiments were conducted that applied this to common transformation problems in the published literature.

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Casselgren, Carl Johan, et Roland Häggkvist. « Completing partial Latin squares with one filled row, column and symbol ». Linköpings universitet, Matematik och tillämpad matematik, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-92689.

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Let P be an n×n partial Latin square every non-empty cell of which lies in a fixed row r, a fixed column c or contains a fixed symbol s. Assume further that s is the symbol of cell (r,c) in P. We prove that P is completable to a Latin square if n≥8 and n is divisible by 4, or n≤7 and n∉{3,4,5}. Moreover, we present a polynomial algorithm for the completion of such a partial Latin square.

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González, Luciano J. « Topological dualities and completions for (distributive) partially ordered sets ». Doctoral thesis, Universitat de Barcelona, 2015. http://hdl.handle.net/10803/314382.

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This PhD thesis is the result of our research on duality theory and completions for partially ordered sets. A first main aim of this dissertation is to propose different kind of topological dualities for some classes of partially ordered sets and a second aim is to try to use these dualities to obtain completions with nice properties. To this end, we intend to follow the line of the classical dualities for bounded distributive lattices due to Stone and Priestley. Thus, we will need to consider a notion of distributivity on partially ordered sets. Also we propose a topological duality for the class of all partially ordered sets and we use this duality to study some properties of partially ordered sets like its canonical extension, order-preserving maps and the extensions of n-ary maps that are order-preserving in each coordinate. Moreover, to attain these aims we will study the partially ordered sets from an algebraic point of view.
Esta tesis doctoral es el resultado de nuestra investigación sobre la teoría de la dualidad y completaciones de conjuntos parcialmente ordenados. Un primer objetivo general de este trabajo es proponer diferentes tipos de dualidades topológicas para algunas clases de conjuntos parcialmente ordenados y un segundo objetivo es tratar de utilizar estas dualidades para obtener diferentes completaciones con buenas propiedades. Para este fin, nos proponemos seguir la línea de las dualidades clásicas para retículos distributivos acotados debidas a Stone y a Priestley. Por lo tanto, necesitaremos considerar una noción de distributividad sobre conjuntos parcialmente ordenados. También proponemos una dualidad topológica para la clase de todos los conjuntos parcialmente ordenados y usamos esta dualidad para estudiar algunas propiedades de los conjuntos parcialmente ordenados como su extensión canónica, funciones que preservan orden y las extensiones de funciones n-arias que preservan orden en cada coordenada. Por otra parte, para alcanzar estos objetivos vamos a estudiar los conjuntos parcialmente ordenados desde un punto de vista algebraico.

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Göransson, Herman. « Completing partial latin squares with 2 filled rows and 3 filled columns ». Thesis, Linköpings universitet, Matematiska institutionen, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-163092.

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The set PLS(a, b; n) is the set of all partial latin squares of order n with a completed rows, b completed columns and all other cells empty. We identify reductions of partial latin squares in PLS(2, 3; n) by using permutations described by filled rows and intersections of filled rows and columns. We find that all partial latin squares in PLS(2, 3;n), where n is sufficiently large, can be completed if such a reduction can be completed. We also show that all partial latin squares in PLS(2, 3; n) where the intersection of filled rows and columns form a latin rectangle have completions for n ≥ 8.

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Bobga, Benkam Benedict Johnson Peter D. « Some necessary conditions for list colorability of graphs and a conjecture on completing partial Latin squares ». Auburn, Ala, 2008. http://repo.lib.auburn.edu/EtdRoot/2008/FALL/Mathematics_and_Statistics/Dissertation/Bobga_Benkam_22.pdf.

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Doerr, Johanna. « Amodal completion of partially occluded letters : an automatic process defining the shape of a completed representation ». Thesis, Lancaster University, 2009. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.543961.

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Brooks, David. « Completing the partial mind : the (im)perfection of the human condition in the later poetry of W.B. Yeats / ». Title page only, 1995. http://web4.library.adelaide.edu.au/theses/09AR/09arb8728.pdf.

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Öhman, Lars-Daniel. « How to do what you want to do when you can not do what you want : on avoiding and completing partial latin squares ». Doctoral thesis, Umeå University, Mathematics and Mathematical Statistics, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-867.

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Öhman, Lars-Daniel. « How to do what you want to do when you can not do what you want : on avoiding and completing partial latin squares / ». Umeå : Department of Mathematics and Mathematical Statistics, Umeå University, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-867.

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Sen, Sagar. « Découverte automatique de modèles effectifs ». Phd thesis, Université Rennes 1, 2010. http://tel.archives-ouvertes.fr/tel-00507530.

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Les découvertes scientifiques aboutissent souvent à la représentation de structures dans l'environnement sous forme de graphes d'objets. Par exemple, certains réseaux de réactions biologiques visent à représenter les processus vitaux tels que la consommation de gras ou l'activation/désactivation des gênes. L'extraction de connaissances à partir d'expérimentations, l'analyse des données et l'inférence conduisent à la découverte de structures effectives dans la nature. Ce processus de découverte scientifiques peut-il être automatisé au moyen de diverses sources de connaissances? Dans cette thèse, nous abordons la même question dans le contexte contemporain de l'ingénierie dirigée par les modèles (IDM) de systèmes logiciels complexes. L'IDM vise à accélérer la création de logiciels complexes en utilisant de artefacts de base appelés modèles. Tout comme le processus de découverte de structures effectives en science un modeleur crée dans un domaine de modélisation des modèles effectifs, qui représente des artefacts logiciels utiles. Dans cette thèse, nous considérons deux domaines de modélisation: métamodèles pour la modélisation des langages et des feature diagrams pour les lignes de produits (LPL) logiciels. Pouvons-nous automatiser la découverte de modèles effectifs dans un domaine de modélisation? Le principal défi dans la découverte est la génération automatique de modèles. Les modèles sont des graphes d'objets interconnectés avec des contraintes sur leur structure et les données qu'ils contiennent. Ces contraintes sont imposées par un domaine de modélisation et des sources hétérogènes de connaissances, incluant plusieurs règles de bonne formation. Comment pouvons-nous générer automatiquement des modèles qui satisfont ces contraintes? Dans cette thèse, nous présentons un framework dirigé par les modèles pour répondre à cette question. Le framework pour la découverte automatique de modèles utilise des sources hétérogènes de connaissances pour construire, dans un premier temps, un sous-ensemble concis et pertinent d'une spécification du domaine de modélisation appelée domaine de modélisation effectif. Ensuite, il transforme le domaine de modélisation effectif défini dans différent langages vers un problème de satisfaction de contraintes dans le langage de spécification formel Alloy. Enfin, le framework invoque un solveur sur le modèle Alloy pour générer un ou plusieurs modèles effectifs. Nous incorporons le framework dans deux outils: PRAMANA pour la découverte de modèles a partir de n'importe quel langage de modélisation et AVISHKAR pour la découverte de produits dans une LPL. Nous validons notre framework par des expérimentations rigoureuses pour la génération de test, la complétion de modèles partiel, la génération de produits, et la génération d'orchestrations web service. Les résultats montrent que notre framework génère systématiquement des solutions effectives dans des domaines de modélisation à partir de cas d'étude significatifs.

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Dimuro, Gracaliz Pereira. « Domínios intervalares da matemática computacional ». reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 1991. http://hdl.handle.net/10183/24890.

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Fundamentada a importância da utilização da Teoria dos Intervalos em computação científica, é realizada uma revisão da Teoria Clássica dos Intervalos, com críticas sobre as incompatibilidades encontradas como motivos de diversas dificuldades para desenvolvimento da própria teoria e, consequentemente, das Técnicas Intervalares. É desenvolvida uma nova abordagem para a Teoria dos Intervalos de acordo com a Teoria dos Domínios e a proposta de [ACI 89], obtendo-se os Domínios Intervalares da Matemática Computacional. Introduz-se uma topologia (Topologia de Scott) compatível com a idéia de aproximação, gerando uma ordem de informação, isto é, para quaisquer intervalos x e y, diz-se que se x -c y , então y fornece mais (no mínimo tanto quanto) informação, sobre um real r, do que x. Prova-se que esta ordem de informação induz uma topologia To (topologia de Scott) , que é mais adequada para uma teoria computacional que a topologia da Hausdorff introduzida por Moore [MOO 66]. Cada número real r é aproximado por intervalos de extremos racionais, os intervalos de informação, que constituem o espaço de informação II(Q), superando assim a regressão infinita da abordagem clássica. Pode-se dizer que todo real r é o supremo de uma cadeia de intervalos com extremos racionais “encaixados”. Assim, os reais são os elementos totais de um domínio contínuo, chamado de Domínio dos Intervalos Reais Parciais, cuja base é o espaço de informação II (Q). Cada função contínua da Análise Real é o limite de sequências de funções contínuas entre elementos da base do domínio. Toda função contínua nestes domínios constitui uma função monotônica na base e é completamente representada em termos finitos. É introduzida uma quasi-métrica que induz uma topologia compatível com esta abordagem e provê as propriedades quantitativas, além de possibilitar a utilização da noção de sequências, limites etc, sem que se precise recorrer a conceitos mais complexos. Desenvolvem-se uma aritmética, critérios de aproximação e os conceito de intervalo ponto médio, intervalo valor absoluto e intervalo diâmetro, conceitos compatíveis com esta abordagem. São acrescentadas as operações de união, interseção e as unárias. Apresenta-se um amplo estudo sobre a função intervalar e a inclusão de imagens de funções, com ênfase na obtenção de uma extensão intervalar natural contínua. Esta é uma abordagem de lógica construtiva e computacional.
The importance of Interval Theory for scientific computation is emphasized. A review of the Classical Theory is macle, including a discussion about some incompatibities that cause problems in developing interval algorithms. A new approach to the Interval Theory is developed in the light of the Theory of Domains and according to the ideas by Acióly [ACI 89], getting the Interval Domains of Computational Mathematics. It is introduced a topology (Scott Topology), which is associated with the idea of approximation, generating an information order, that is, for any intervals x and y one says that if x -c y, then "the information given by y is better or at least equal than the one given by x". One proves that this information order induces a To topology (Scott's topology) which is more suitable for a computation theory than that of Hausdorff introduced by Moore [MOO 66]. This approach has the advantage of being both of constructive logic and computational. Each real number is approximated by intervals with rational bounds, named information intervals of the Information Space II(Q), eliminating the infinite regression found in the classical approach. One can say that every real a is the supreme of a chain of rational intervals. Then, the real numbers are the total elements of a continuous domain, named the Domain of the Partial Real Intervals, whose basis is the information space II (Q). Each continuous function in the Real Analysis is the limit of sequences of continuous functions among any elements which belong to the base of the domain. In these same domains, each continuous function is monotonic on the base and it is completely represented by finite terms. It is introduced a quasi-metric that leads to a compatible topology and supplies the quantitative properties. An arithmetic, some approximation criteria, the concepts of mean point interval, absolute value interval and width interval are developed and set operations are added. The ideas of interval functions and the inclusion of ranges of functions are also presented, and a continuous natural interval extension is obtained.

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Tang, Chang-Jei, et 唐盛吉. « Partial Discharge Detection Techniques Applied to Completion and Acceptance of XLPE Power Cables ». Thesis, 2012. http://ndltd.ncl.edu.tw/handle/80406096229551702558.

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碩士
國立臺灣海洋大學
電機工程學系
100
Through the survey, we found that most of the power cables, most accidents occurred on the cable terminal processing head and joint , mainly because of flaws in the human construction, traditional testing methods can not effectively prevent the cable from the accident, you must combine the AC voltage test and a sensitive partial discharge measurements in order to achieve the best test results. This thesis from the formation of the cable partial discharge, the occurrence of the conditions and factors of the partial discharge theory for analysis, and examples of domestic and foreign situations for the use of partial discharge, and finally the actual description of the cable terminal processing head after the installation is complete, the AC series resonant voltage to the completion of acceptance testing, and implementation of the partial discharge measurement situation. Based on the importance of the substation equipment currently used in multi-line partial discharge measurement sensors for contactless, and more generally used as power cable insulation condition assessment.UHF sensors and data collection for the new system used in this paper, a fixed continuous partial discharge monitoring to monitor the side of the status of the GIS side and outdoor cable terminations, and the detection of pattern and noise effectively identification, only in operation for continuous monitoring in order to provide sufficient information in order to reduce the accident rate and improve the electricity cables running quality management.

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Sele, Morten. « Defining public relations in New Zealand through its history and practice. Dissertation in partial completion of Master of International Communication COMM 9181 / ». Diss., 2006. http://www.coda.ac.nz/cgi/viewcontent.cgi?article=1006&context=unitec_comm_di.

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Nel, Liza. « The usefulness of corporate ethics programmes in integrating ethics into an organisation's culture. Dissertation in partial completion of Master of International Communication, Unitec New Zealand / ». Diss., 2008. http://www.coda.ac.nz/cgi/viewcontent.cgi?article=1004&context=unitec_comm_di.

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Bartos, Janice Theriault Joseph C. « Enhancing the design of high school completion programs for pregnant and parenting teens a report submitted in partial fulfillment ... for the degree of Master of Science, Parent-Child Nursing ... / ». 1997. http://catalog.hathitrust.org/api/volumes/oclc/68799611.html.

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Bartlett, Padraic James. « Completions of ε-Dense Partial Latin Squares ». Thesis, 2013. https://thesis.library.caltech.edu/7819/1/caltech_dissertation_padraic_draft.pdf.

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A classical question in combinatorics is the following: given a partial Latin square $P$, when can we complete $P$ to a Latin square $L$? In this paper, we investigate the class of textbf{$epsilon$-dense partial Latin squares}: partial Latin squares in which each symbol, row, and column contains no more than $epsilon n$-many nonblank cells. Based on a conjecture of Nash-Williams, Daykin and H"aggkvist conjectured that all $frac{1}{4}$-dense partial Latin squares are completable. In this paper, we will discuss the proof methods and results used in previous attempts to resolve this conjecture, introduce a novel technique derived from a paper by Jacobson and Matthews on generating random Latin squares, and use this novel technique to study $ epsilon$-dense partial Latin squares that contain no more than $delta n^2$ filled cells in total.

In Chapter 2, we construct completions for all $ epsilon$-dense partial Latin squares containing no more than $delta n^2$ filled cells in total, given that $epsilon < frac{1}{12}, delta < frac{ left(1-12epsilonright)^{2}}{10409}$. In particular, we show that all $9.8 cdot 10^{-5}$-dense partial Latin squares are completable. In Chapter 4, we augment these results by roughly a factor of two using some probabilistic techniques. These results improve prior work by Gustavsson, which required $epsilon = delta leq 10^{-7}$, as well as Chetwynd and H"aggkvist, which required $epsilon = delta = 10^{-5}$, $n$ even and greater than $10^7$.

If we omit the probabilistic techniques noted above, we further show that such completions can always be found in polynomial time. This contrasts a result of Colbourn, which states that completing arbitrary partial Latin squares is an NP-complete task. In Chapter 3, we strengthen Colbourn's result to the claim that completing an arbitrary $left(frac{1}{2} + epsilonright)$-dense partial Latin square is NP-complete, for any $epsilon > 0$.

Colbourn's result hinges heavily on a connection between triangulations of tripartite graphs and Latin squares. Motivated by this, we use our results on Latin squares to prove that any tripartite graph $G = (V_1, V_2, V_3)$ such that begin{itemize} item $|V_1| = |V_2| = |V_3| = n$, item For every vertex $v in V_i$, $deg_+(v) = deg_-(v) geq (1- epsilon)n,$ and item $|E(G)| > (1 - delta)cdot 3n^2$ end{itemize} admits a triangulation, if $epsilon < frac{1}{132}$, $delta < frac{(1 -132epsilon)^2 }{83272}$. In particular, this holds when $epsilon = delta=1.197 cdot 10^{-5}$.

This strengthens results of Gustavsson, which requires $epsilon = delta = 10^{-7}$.

In an unrelated vein, Chapter 6 explores the class of textbf{quasirandom graphs}, a notion first introduced by Chung, Graham and Wilson cite{chung1989quasi} in 1989. Roughly speaking, a sequence of graphs is called "quasirandom"' if it has a number of properties possessed by the random graph, all of which turn out to be equivalent. In this chapter, we study possible extensions of these results to random $k$-edge colorings, and create an analogue of Chung, Graham and Wilson's result for such colorings.

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Hamidi, Alireza. « An aggregative approach for scalable detection of DoS attacks ». Thesis, 2008. http://hdl.handle.net/1828/1084.

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If not the most, one of the serious threats to data networks, particularly pervasive commercial networks such as Voice-over-IP (VoIP) providers is Denial-of-Service (DoS) attack. Currently, majority of solutions for these attacks focus on observing detailed server state changes due to any or some of the incoming messages. This approach however requires significant amount of server’s memory and processing time. This results in detectors not being able to scale up to the network edge points that receive millions of connections (requests) per second. To solve this problem, it is desirable to design stateless detection mechanisms. One approach is to aggregate transactions into groups. This research focuses on stateless scalable DoS intrusion detection mechanisms to obviate keeping detailed state for connections while maintaining acceptable efficiency. To this end, we adopt a two-layer aggregation scheme termed Advanced Partial Completion Filters (APCF), an intrusion detection model that defends against DoS attacks without tracking state information of each individual connection. Analytical as well as simulation analysis is performed on the proposed APCF. A simulation test bed has been implemented in OMNET++ and through simulations it is observed that APCF gained notable detection rates in terms of false positive and true positive detections, as opposed to its predecessor PCF. Although further study is needed to relate APCF adjustments to a certain network situation, this research shows invaluable gain to mitigate intrusion detection from not so scalable state-full mechanisms to aggregate scalable approach.

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Thèses sur le sujet « PARTIAL COMPLETION »

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