Le financement à court terme est le parent pauvre de la théorie financière. Pourtant, les moyennes entreprises françaises utilisent fortement ce financement. Ce travail a pour objectif d’analyser les déterminants du financement à court terme pour ces entreprises. La première partie vise à établir une revue de littérature des théories permettant d’expliquer l’utilisation du financement à court terme. La deuxième partie vient tester empiriquement ces théories sur deux échantillons, à savoir 201 entreprises familiales et 1 453 entreprises managériales. Il s’agit, d’une part, de caractériser les moyennes entreprises non cotées et d’autres part, de mettre en évidence les déterminants à l’utilisation de financement à court terme. Les principaux résultats indiquent que le financement à court terme est un outil de gestion au service de la moyenne entreprise. Il peut aussi assumer deux rôles, un compensatoire et/ou un de trésorerie passive. Par ailleurs, on met en évidence que les entreprises managériales et familiales exploitent différemment le financement à court terme. / Short-term financing is forgotten by theory of corporate finance. However, French medium-sized firms use a lot this source of funding. The objective of this thesis is to analyze the determinants of short-term financing for these firms. The first part aims to establish a literature review of theories to explain the use of short-term financing. The second part empirically checks these theories on two samples, specifically 201 family businesses and 1,453 managerial firms. On the one hand, it is a question of characterizing the unlisted medium-sized enterprises and on the other hand, highlighting the determinants of the use of short-term financing. The primary results indicate that short-term financing is a management tool for the medium-sized enterprise. It can also have two functions, one compensatory and / or one passive cash. Furthermore, it brings out that managerial and family businesses exploit short-term financing differently.

La décision de détention d’actifs liquides par les entreprises a fait l’objet de rares recherches. Pourtant,les entreprises françaises détiennent des niveaux importants de liquidités parmi leurs actifs. Ce travailvise à étudier théoriquement et empiriquement les motivations et les conséquences de la décision dedétention d’actifs liquides par les entreprises.La première partie de la thèse a pour objectif d’établir un état de l’art des théories explicatives ducomportement accumulateur de liquidités des entreprises. La deuxième partie cherche à testerempiriquement ces théories sur un échantillon de 202 entreprises françaises cotées au SBF 250. Il s’agit,d’un côté, de vérifier s’il existe un niveau optimal d’actifs liquides, de présenter les différents avantageset inconvénients de la détention de liquidités et de déterminer quels facteurs intrinsèques (financiers etorganisationnels) et macro-économiques influencent le niveau de liquidités, et d’un autre côté, d’estimerl’impact des actifs liquides sur l’investissement, la performance économique et financière ainsi que surla valeur de marché de l’entreprise. Le traitement de ces deux questions est articulé autour de l’étudedes rôles modérateurs des contraintes de financement, de la gouvernance d’entreprise et des conditionsmacroéconomiques. / The topic of corporate cash holdings has received relatively little attention from the academicresearchers. Yet, French firms hold significant cash reserves. This research aims to investigate,theoretically and empirically, the motivations and implications of the decision to hold cash.The first part of the thesis aims to provide a state of the art of the theories explaining corporate cashholding behavior. The second part seeks to empirically test these theories on a sample of 202 Frenchcompanies listed on the SBF 250. We first test the existence of an optimal level of liquid assets. Wesubsequently explore the advantages and disadvantages of holding cash before we examine the specific(financial and organizational) and macro-economic determinants of corporate cash levels. Finally, weestimate the impact of liquid assets on firms’ investment, performance and value and then we analyzethe moderating roles of financial constraints, corporate governance and macroeconomic conditions.

Syftet med denna studie är att undersöka och analysera det statistiska signifikanta sambandet mellan kapitalstruktur och lönsamhet för bolag noterade på OMXS Large Cap. Det görs under tidsperioden före samt under Covid-19 och studien använder sig av ett antal variabler för att kunna analysera ett potentiellt samband över en femårsperiod. Uppsatsen undersöker även om det eventuella sambandet ändras av Covid-19 pandemin. Studien har utgått ifrån en kvantitativ metod med en deduktiv ansats. För att ge svar på forskningsfrågan har paneldata regressioner genomförts på 30 bolag noterade på OMXS Large Cap för perioderna 2017-2019 och 2020-2021. Studien kommer fram till att det finns statistiskt signifikanta samband mellan kapitalstruktur och lönsamhet avseende vissa variabler samtidigt som studien finner att det inte finns samband för vissa andra variabler. Resultaten visar på både negativa och neutrala samband och slutsatsen att hög skuldsättningsgrad har en negativ effekt på lönsamhet dras, vilket stämmer överens med tidigare forskning inom ämnet. Sambanden som hittades visade sig ändras mellan perioden innan och under Covid-19 / The purpose of this study is to investigate the statistically significant relationship between capital structure and profitability for companies listed on OMXS Large Cap. This is done in connection with Covid-19 and the study uses a number of variables to analyze a potential relationship over a five-year period. The study  further examines if the possible relationship is affected by Covid-19. The study has been based on a quantitative method with a deductive approach. In order to answer the purpose of the study, the authors have carried out panel data regressions on 30 companies listed on OMXS Large Cap for the periods 2017-2019 and 2020-2021. The study finds that there exists statistically significant relationships between capital structure and profitability for some of the variables, whilst other variables show no significance. The results show both negative and neutral relations and the conclusion that a higher debt ratio has a negative effect on profitability is drawn, showing the same result as previous research. The results also show that the relationships differ from before the pandemic period to under.

Syftet med denna studie är att analysera eventuella kapitalstruktursförändringar i samband med Covid-19 pandemin hos svenska företag noterade på Stockholmsbörsen, OMXS, inom Large Cap. Urvalet utgörs av företag inom alla sektorer i Large Cap, exklusive finanssektorn. Sambandet mellan bolagens beroende och oberoende variabler analyseras före och under pandemins tidsperiod, 2015–2022. De beroende variablerna utgörs som Proxy för kapitalstruktur och omfattas av totala-, kortfristiga-, och långfristiga skulder i förhållande till totala tillgångar. Medan de oberoende variablerna utgörs av företagsstorlek, lönsamhet samt tillväxt. För att uppnå detta baseras uppsatsens teoretiska ramverk på Modigliani och Miller proposition 1 & 2, Pecking Order teorin och Trade Off teorin tillsammans med tidigare empiriska studier samt undersökningar. Uppsatsens analyser omfattas av en deskriptiv analys av samtliga variabler, en korrelationsanalys av de oberoende variablerna och slutligen flera multivariata regressionsanalyser mellan samtliga variabler. För att erhålla de mest valida och reliabla slutsatserna kommer uppsatsen tillämpa en kvantitativ forskningsmetod och en deduktiv ansats. Uppsatsens resultat fann flest statistiskt signifikanta samband mellan samtliga skuldkvoter och företagsstorlek. Uppsatsens slutsats konstaterade att kapitalstrukturen hos OMXS företag inom Large Cap hade förändrats under pandemin i jämförelse med före pandemin. Sammantaget bidrar denna uppsats till en djupare förståelse för sambandet mellan samtliga analyserade variabler baserat på en historisk bakgrund. Därmed kan svenska bolag inom alla sektorer, exklusive finanssektorn, skapa en bättre uppfattning kring sina kapitalstrukturer inför framtida finanskriser. / The purpose of this study is to analyze potential capital structure changes in connection with the Covid-19 pandemic among Swedish publicly traded companies on the Stockholm Stock Exchange, OMXS, within Large Cap. The sample consists of companies across all sectors within Large Cap, excluding the finance sector. Focusing on the relationship between the dependent and independent variables before and during the period of the pandemic, 2015–2022. The dependent variables consist of total-, short- term-, and long- term debt as a proportion to the total assets. These dependent variables constitute as a Proxy for capital structure. The independent variables include size, profitability and growth. To accomplish this, the theoretical framework for this essay is based on Modigliani and Miller proposition 1 & 2, The Pecking Order Theory, The Trade Off Theory along with previous empirical studies. The analyzes contains of a descriptive analysis of all variables, a correlation analysis of the independent variables, and lastly several multivariate regressions analyses between all variables. In order to make it possible to acquire the most valid and reliable conclusions, the study will be based on a quantitative method, applying a deductive approach. The results found the most statistically significant relationships between all debt ratios and company size. The conclusion stated that the capital structure of OMXS companies, within Large Cap, had changed during the pandemic compared to before. In summary the results contribute to a deeper understanding of the relationship between all analyzed variables based on a historical background. Hence Swedish companies within these sectors can gain a better understanding of their capital structure for future financial crises.

La thèse est consacrée à des problématiques d’algorithmique et de complexité sur deux sujets. Le premier sujet s’intéresse à la composition comportementale des services web. Ce problème a été réduit à la simulation d’un automate par le produit fermé d’un ensemble d’automates. La thèse étudie dans sa première partie la complexité de ce problème en considérant deux paramètres : le nombre des instances considéré de chaque service et la présence des états hybrides : état à la fois intermédiaire et final dans un automate. Le second sujet porte sur les systèmes de fermeture et s’intéresse au calcul de l’extension maximale d’un système de fermeture ainsi qu’à l’énumération des clefs candidates d’une base implicative. On donne un algorithme incrémental polynomial qui génère l’extension maximale d’un treillis codé par une relation binaire. Puis, la notion de key-ideal est définie, en prouvant que leur énumération est équivalente à l’énumération des clefs candidates. Ensuite, on donne un algorithme qui permet de générer les key-ideal minimaux en temps incrémental polynomial et les key-ideal non minimaux en délai polynomial. / This thesis investigates complexity and computational issues in two parts. The first concerns an issue related to web services composition problem: Deciding whether the behaviour of a web service can be composed out of an existing repository of web services. This question has been reduced to simulating a finite automata to the product closure of an automata set. We study the complexity of this problem considering two parameters; the number of considered instances in the composition and the presence of the so-called hybrid states (states that are both intermediate and final). The second part concerns closure systems and two related issues; Maximal extension of a closure system : we give an incremental polynomial algorithm that computes a lattice's maximal extension when the input is a binary relation. Candidate keys enumeration : we introduce the notion of key-ideal sets and prove that their enumeration is equivalent to candidate keys enumeration. We then give an efficient algorithm that generates all non-minimal key-ideal sets in a polynomial delay and all minimal ones in incremental polynomial time.

This diploma thesis deals with the subject of slenderness bars’ stability assessment, especially in the steel structures. Before the assessment of bars in the frame constructions, we search for the influence of the computational model’s settings on the final result. The initial geometrical imperfections are examined on the model of Euler’s bar. The influence of the rigidity of girders on the poles’ buckling length is examined on the basic frame construction. The buckling lengths are assessed in the comparison with the figures we got from the statistical tables and the computational software. The influence of construction’s initial tilt and its replacement by the system of outer forces is examined on the frame structure. Three-hinged frame structure with variable cross-section member is designed then and the influence of non-linear calculations on the inner forces is studied. In the complex frame assessment, the influence of the number of parts of variable cross-section member on the bars’ buckling length is examined.