Academic literature on the topic 'Frictions de marché'
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Journal articles on the topic "Frictions de marché"
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Lentz, Rasmus. "Models of Wages and Mobility in Frictional Labor Markets with Random Search." Revue économique Vol. 51, no. 1 (February 27, 2024): 113–45. http://dx.doi.org/10.3917/reco.751.0113.
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J’étudie les modèles de détermination de l’équilibre des salaires et de la mobilité avec frictions sur le marché du travail. La recherche d’un emploi est aléatoire. La concurrence entre les entreprises se fait en termes de promesses de valeur faites aux travailleurs. La nature exacte de cette concurrence dicte la répartition des promesses de valeur dans l’économie. La mobilité des travailleurs et l’allocation des emplois sont souvent comprises directement à partir de cette partie du modèle. L’étude détaille comment les restrictions sur les contrats de travail traduisent les valeurs des contrats en salaires .
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Thibout, Charles. "Les ancrages nationaux d’une multinationale." Réseaux N° 244, no. 3 (September 30, 2024): 187–224. http://dx.doi.org/10.3917/res.245.0187.
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Si le pouvoir des multinationales, et des GAFAM en particulier, apparaît comme l’un des faits politiques et économiques majeurs de notre époque, s’exerce-t-il sans frictions au contact des espaces de pouvoir nationaux qu’elles rencontrent au gré de leur internationalisation ? Cet article entend contribuer à y répondre, en analysant l’implantation de Google en France à travers le prisme de ses recrutements. Fondée sur des entretiens, l’exploitation d’archives et une analyse prosopographique, cette enquête permet de rendre compte des efforts d’adaptation produits par une multinationale du numérique pour pénétrer le marché français, alors que la firme est précocement l’objet de mobilisations hostiles et d’une mise en problème politique. L’objectif de l’article est d’analyser ce processus d’adaptation, qui passe par le recrutement de salariés et de dirigeants aux propriétés hybrides, situés à l’interface entre Google et le champ du pouvoir national. Les ancrages nationaux de ces recrues en général, et des représentants d’intérêts en particulier, aménagent des espaces de négociation où se jouent l’entrée de la firme dans le travail gouvernemental et la reconnaissance de sa légitimité à s’insérer dans certains secteurs d’action publique.
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Restrepo, María Isabel, and Diana Constanza Restrepo. "El canal del crédito bancario en Colombia: 1995-2005. Una aproximación mediante modelos de umbral." Lecturas de Economía, no. 67 (July 31, 2009): 99–118. http://dx.doi.org/10.17533/udea.le.n67a2022.
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El canal del crédito bancario, que amplifica los efectos del canal tradicional de la política monetaria, hace énfasis en la estructura y las fricciones del mercado financiero como determinantes del gasto agregado. Este artículo analiza y verifica la existencia del canal del crédito bancario en Colombia estimando un modelo propuesto por Michael Gibson en 19971997, quien utiliza regresiones de umbral para determinar el impacto de la política monetaria sobre la demanda agregada. Los resultados obtenidos no permiten descartar la existencia de este mecanismo de transmisión en Colombia durante el periodo analizado, aunque éste parece operar solo a través de la política monetaria contraccionista. Palabras clave: política monetaria, mecanismos de transmisión, canal de crédito bancario, modelos de umbral. Clasificación JEL: C12, C52, E44, E52, G11. Abstract: The Bank Credit Channel, which amplifies the effects of the traditional channel of monetary policy, emphasizes on the structure and frictions of financial markets as determinants of aggregate spending. This paper aims at analyze and verify the existence of the bank credit channel in Colombia estimating a model proposed by Gibson (1997) which uses threshold regressions as a way to determine the impact of monetary policy on aggregate demand. Results do not allow dismissing the existence of this transmission mechanism in Colombia during the analyzed period, although it seems to operate only through contractionary monetary policy. Keywords: monetary policy, transmission mechanisms, bank lending channel, threshold regressions. JEL classification: C12, C52, E44, E52, G11. Résumé: Le canal du crédit bancaire amplifie les effets du canal traditionnel de la politique monétaire et met l.accent sur la structure et sur les frictions du marché financier, lesquels constituent les éléments qui déterminent de la dépense agrégée. L.objectif de cet article est d.analyser et de vérifier l.existence du canal du crédit bancaire en Colombie en estimant le modèle proposé par Michael Gibson en 1997, lequel utilise des régressions à seuil pour déterminer l.impact de la politique monétaire sur la demande agrégée. Les résultats obtenus ne permettent pas d.écarter l.existence d.un mécanisme de transmission pendant la période analysée, malgré le fait qu.il ne paraisse agir qu.à travers une politique monétaire restrictive. Mots clef: politique monétaire, mécanismes de transmission, canal du crédit bancaire, modèles à seuil. Classification JEL: C12, C52, E44, E52, G11.
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Tripier, Fabien. "Frictions de recherche sur les marchés financiers." Revue française d'économie XXVIII, no. 4 (2013): 15. http://dx.doi.org/10.3917/rfe.134.0015.
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Whitehall, Geoffrey, and Victoria Silva Sánchez. "In different states of indifference: movement, friction, and resistance." Relaciones Internacionales, no. 54 (October 24, 2023): 39–56. http://dx.doi.org/10.15366/relacionesinternacionales2023.54.002.
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. This article critically engages with the question of mobility in the study of international politics by centering the concept of resistance. It starts with the example of the Canadian Government blocking the Roxham Road irregular border crossing in March 2023 and Canadian officials arguing in favour of normalizing movement between the US/Canada. In general, the paper challenges the global state centric project of normalizing movement by arguing that resistance always comes first. As such, this challenge does not only ask who/what gets to move freely and when; it is centers the very resistances to normalizing movement that emerges from within and without movement itself. The paper has three sections: the first acknowledges that celebrating movement is important because it loosens the state centric study of international politics and sets borders, states, and migrants adrift in a sea of irregular movements. It creates a differential analysis of movement which I refer to as “differential encounters”. In the context of this article, recasting the state in the context of movement demands an engagement with Indigenous and migrant histories beyond the modern categories of immigrant or settler. It requires going beyond merely placing Indigenous peoples into other non-Indigenous migrations stories since it reproduces the colonial efforts to exceptionalize the immigrant experience in and through its universalization/provincialization. Such practical efforts to normalize movement allow the Canadian state to present itself as the apolitical and fixed arbiter of different movements and thereby displace the unceded mediating role inherent to Indigenous relationships to the land and its peoples. The second section shifts to an epistemological register of movements to recognize that celebrating movement can also depoliticize movements differences. Therefore, movement is not simply given; it is itself treated as diagnostic and productive by attending to the function of friction inside and between movements. Following the work of Anna Tsing, frictions are not only the product of movement but also the shapers and materializers of movement(s). They are the encounters that actualize, materialize, and define movements. They occur when movements interact, and they produce something new within the specific place-based context of differential encounters. Friction is becoming movement because nothing moves or matters without friction. This section “matters” the nine individuals, including two children, who lost their lives while being smuggled through the Akwesasne district of the St. Lawrence River, which straddles the US/Canada border. Their lives are mattered in and through the materialization of movements. Yet, in differential encounters, there can be no sovereign, disciplinary, or biopolitical accounting of bodies and lives: only frictions, movements, and resistances. These frictions both materialize and are material. They are historical and immediate. From macro to micro: the decision to deploy a particular technology is as significant as the reliability of an operation, machine, or equipment in the day to day. The political frictions between movements, as such, become the focus of studies which centre movement. To find politics one must move with resistance. To move with resistance is to open untoward frictions. Moving with resistance politicizes those very movements and frictions that have become regularized and/or normalized. The final section argues that despite the emancipatory narrative attached to privileging ontological and epistemological approaches, resistance should always be situated as a generative force that comes first. This section uses the four-part documentary series Thunder Bay (2023), by Ryan McMahonm, the award winning Anishinaabe journalist, to investigates forms of resistance in Thunder Bay, Ontario, which sits at the head of Lake Superior. The history of Thunder Bay is defined by Indigenous/settler relations —a complex of trade, employment, governance, policing, and personal frictions —and amass into the colonial frictions of the city. Thunder Bay’s purpose has not changed. It continues to exist in order to control, extract and extinguish Indigenous futures. While the documentary challenges the audience to see Thunder Bay as both an exceptional crisis in policing and as an exemplar case of continued Canadian colonialism, McMahon’s series also helps the effort in this paper to rethink the concept of resistance in the context of movement and friction. To think about resistance as coming first, the concept of resistance itself must be redefined, not as opposition or reaction, but as an enduring medium of escalation and indifference. Resisting colonialism cannot erase its constitutive frictions; colonialism is a movement responding to already existing resistance, friction and movement. As such, the colonial project remains intact, and escalation adds new opportunities for the state to escalate in turn. Thunder Bay laments that, despite the inspiring efforts of individuals and movements, Indigenous resistance is reduced to new and further instances of friction that keep the wheels of the Canadian state turning. Resistance in movement is a prior interplay of indifferently releasing one movement and politically escalating other emergent movements that resurface in the wake. The article puts special attention to the concept of indifference since “to indiffer” break or turn away from the modern state form, is to actively dismantle those escalatory forces of resistance and friction captured by the state’s ambition to appear static. However, just as resistance has come to mean opposition to movement and lost its political value, indifference has also been cast as a static apolitical form of being. Again, just as resistance escalates, it also indiffers. To indiffer evokes differing, but not in ways that contribute to a particular movement’s escalation or friction. Instead, indiffering releases, liberates, suspends both escalation and friction. This does not mean that indifference has no relationship with escalation or friction in the abstract. To indiffer is an active unattending to a movement’s particular escalation and friction. It is resisting, releasing, and forgetting and generating new frictions and movements. Yet indifference is not innocent —it is not only a weapon of the weak. The state also practices indifference. The indifferent state actively uncares about Indigenous lives because its own future requires unmaking of Indigenous future horizons. This article suggests that if resistance is no longer believed to be a willful action of the liberal subject, and resistance always comes in advance, then the frictions that unfold as movements inevitably unmap geographies of the state and open untoward irregular movements and futures.
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Lesourne, Jacques. "Le marché et l’auto-organisation." Économie appliquée 38, no. 3 (1985): 663–701. http://dx.doi.org/10.3406/ecoap.1985.4057.
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The paper presents an on-going research on the occurrence of self-organization as a consequence of market dynamics. After an analysis of a labour market on which workers look for jobs, negociate with firms and adapt, as well as the latters, their requirements through time, the paper introduces successively information constraints, friction costs, location costs, information costs, then examines more complex set ups. In one of them, workers may acquire new professional abilities when employed by given firms, the structure of the future labour supply being thus randomly generated by market dynamics. It is shown in the conclusion that a market may be considered as an autopoïetic system.
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Renkin, Hadley Z. "Perverse Frictions: Pride, Dignity, and the Budapest LGBT March." Ethnos 80, no. 3 (March 5, 2014): 409–32. http://dx.doi.org/10.1080/00141844.2013.879197.
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Vadacca, Luigi. "The Altotiberina Low-Angle Normal Fault (Italy) Can Fail in Moderate-Magnitude Earthquakes as a Result of Stress Transfer from Stable Creeping Fault Area." Geosciences 10, no. 4 (April 16, 2020): 144. http://dx.doi.org/10.3390/geosciences10040144.
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Geological and geophysical evidence suggests that the Altotiberina low-angle (dip angle of 15–20 ° ) normal fault is active in the Umbria–Marche sector of the Northern Apennine thrust belt (Italy). The fault plane is 70 km long and 40 km wide, larger and hence potentially more destructive than the faults that generated the last major earthquakes in Italy. However, the seismic potential associated with the Altotiberina fault is strongly debated. In fact, the mechanical behavior of this fault is complex, characterized by locked fault patches with a potentially seismic behavior surrounded by aseismic creeping areas. No historical moderate (5 ≤ Mw ≤ 5.9) nor strong (6 ≤ Mw ≤ 6.9)-magnitude earthquakes are unambiguously associated with the Altotiberina fault; however, microseismicity is scattered below 5 km within the fault zone. Here we provide mechanical evidence for the potential activation of the Altotiberina fault in moderate-magnitude earthquakes due to stress transfer from creeping fault areas to locked fault patches. The tectonic extension in the Umbria–Marche crustal sector of the Northern Apennines is simulated by a geomechanical numerical model that includes slip events along the Altotiberina and its main seismic antithetic fault, the Gubbio fault. The seismic cycles on the fault planes are simulated by assuming rate-and-state friction. The spatial variation of the frictional parameters is obtained by combining the interseismic coupling degree of the Altotiberina fault with friction laboratory measurements on samples from the Zuccale low- angle normal fault located in the Elba island (Italy), considered an older exhumed analogue of Altotiberina fault. This work contributes a better estimate of the seismic potential associated with the Altotiberina fault and, more generally, to low-angle normal faults with mixed-mode slip behavior.
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Ramirez-Zamudio, Aldo, and Elmer Sanchez Davila. "Lessons from COVID’S Vaccination: External-Internal Frictions and Efficiency." Vaccines 11, no. 2 (January 22, 2023): 248. http://dx.doi.org/10.3390/vaccines11020248.
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This paper explores some economic variables that determine the emerging of new COVID-19 variants and the determinants of vaccination advances in 108 countries during a quarterly period from March 2020 to March 2022. We found that more people being fully vaccinated and more education (measured as schooling years) decrease the probability of the emergence of new COVID-19 variants, but more crowded cities and higher percentages of urban population increase that probability. Furthermore, we found that the percentage of fully vaccinated people depends positively on the country’s preparation to respond to a health crisis, educational levels, and the index of economic complexity (which measures how diverse in the production of goods and services a country is and the level of its infrastructure), and it depends negatively on the percentage of rural populations (which makes vaccination more difficult).
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Smith, Roderick A. "Kenneth Langstreth Johnson. 19 March 1925 — 21 September 2015." Biographical Memoirs of Fellows of the Royal Society 62 (January 2016): 247–65. http://dx.doi.org/10.1098/rsbm.2016.0012.
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Kenneth Johnson, born in Barrow in 1925, studied mechanical engineering at Manchester during World War II. After some years in industry and an early appointment back in Manchester, he spent most of his academic career teaching and researching at the Engineering Department of Cambridge University. He was also a long-serving Fellow of Jesus College. He was renowned for the insightful analysis of meticulous experiments in contact mechanics. He was widely acknowledged as the doyen of this area, particularly after the publication of his seminal work of the same name. His major publications included topics in friction and wear, rheology and lubrication, rolling contact and adhesion. Important applications of his insights included the prediction of corrugations and cracks in railway lines. He was gratified when, after many years of dormancy, his ideas in adhesion were used by others to explain the climbing behaviours of insects and other small animals with soft feet. He was a devoted family man, characterized by warm personal qualities that won him many friends around the world.
Dissertations / Theses on the topic "Frictions de marché"
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Sales, Marine. "Frictions financières et marché du travail." Thesis, Université Paris-Saclay (ComUE), 2018. http://www.theses.fr/2018SACLN041/document.
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Les niveaux des taux de chômage des économies développés sont aujourd'hui sensiblement différents. Les institutions du marché du travail sont elles aussi diverses et protéiformes selon les pays. Ces institutions pourraient être considérées comme permettant d'accroître ou de réduire les niveaux de chômage. Or empiriquement, on ne trouve pas de lien direct et univoque entre les taux de chômage et les institutions sur le marché du travail. Si nous considérons plus précisément la façon dont les firmes décident de leur masse salariale, on réalise que l'on omet en faisant ce simple lien de corrélation, une variable essentielle qui détermine les comportements d'embauche et de licenciement des entreprises, à savoir la variable du financement. La capacité de financement externe des firmes pourrait déterminer, ou non, la demande de travail, conditionnellement aux institutions sur le marché du travail. Ainsi, le problème ne serait pas de savoir si les institutions sur le marché du travail conditionnent sa performance relative mais plutôt de savoir si le couple d'institutions sur le marché du travail et le marché du crédit détermine ces performances. Une entreprise est certes contrainte par la plus ou moindre grande flexibilité existante sur le marché du travail, mais ses calculs s'inscrivent dans une perspective plus large, qui est de savoir si elle a accès ou non aux financements dont elle a besoin. L'importance des frictions financières sur le marché du crédit détermine le niveau de la contrainte de financement externe pour les firmes. Cela pourrait alors avoir un impact sur leurs projets d'embauche et sur les niveaux d'emplois dans les économies. Les niveaux de frictions financières devraient donc influencer le niveau des principales variables macroéconomiques relatives au marché du travail, que sont le chômage, le niveau du salaire et le nombre de postes vacants, conditionnellement aux institutions existantes sur le marché du travailUnemployment rates in developed economies are now significantly different. Labor market institutions are also diverse and multifaceted. These institutions could be considered as allowing to increase or to reduce the levels of unemployment. However empirically, there is no direct and unambiguous link between unemployment rates and institutions in the labor market. By considering more precisely the way in which firms decide on their payroll, we realize that we omit, by making this simple correlation link, an essential variable that determines the hiring and firing behavior of firms, namely the funding variable. The external financing capacity of firms may determine the labor demand, conditional on the institutions in the labor market. Thus, the problem is not whether institutions in the labor market condition its relative performance but rather whether the couple of institutions in labor and credit markets determines this performance. A firm is certainly constrained by a greater or lesser flexibility in the labor market, but its computations are part of a broader perspective, which is whether or not it has access to the funding it needs. The importance of financial frictions in the credit market determines the level of the external financing constraint for firms. This could then have an impact on their hiring plans and job levels in economies depending on the prevailing labor market institutions. Financial frictions should therefore influence the main labor market macroeconomic variables, namely unemployment, wage level and the number of vacancies, conditional on existing labor market institutions
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Lacaussade, Charles-Thierry. "Evaluation d'actifs financiers et frictions de marché." Electronic Thesis or Diss., Université Paris sciences et lettres, 2024. http://www.theses.fr/2024UPSLD021.
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Cette thèse vise à fournir des méthodes théoriques et empiriques innovantes dans le cadre de l'évaluation des actifs financiers aux chercheurs en économie, aux teneurs de marché et aux différents acteurs de marché, dont les courtiers, les négociants, les gestionnaires d'actifs et les régulateurs. Nous proposons une extension du théorème fondamental de l'évaluation des actifs (FTAP) adaptée aux marchés présentant des frictions financières. Par conséquent, nos méthodes d'évaluation des actifs permettent d'obtenir un système de prix présentant des bid-ask spreads (écarts entre le prix d’achat et de vente), tels qu'ils sont observés sur les marchés financiers ce qui les rendent plus facilement interprétables. Dans le premier chapitre, nous introduisons deux théorèmes de représentation pour l'évaluation des actifs financiers sur les marchés à deux dates, en tenant compte d'une variété de frictions financières (coûts de transaction, taxes, frais de commission). Ce résultat repose sur une nouvelle condition d'absence d'arbitrage adaptée au marché avec frictions financières, qui prend en compte les stratégies potentielles d'achat et de vente. En outre, ces modèles d'évaluation des actifs reposent tous deux sur des mesures de probabilité non additives. Le premier modèle est une règle de prix de Choquet, pour laquelle nous proposons un cas particulier adapté à la calibration, et le second est une règle d'évaluation à priors multiples. Dans le deuxième chapitre, en vue de généraliser nos modèles d'évaluation des actifs, nous fournissons les conditions nécessaires et suffisantes pour des règles de prix de Choquet en multi-périodes caractérisées notamment par l’existence des bid-ask spreads. Nous montrons qu'il est possible de modéliser un problème de tarification dynamique sur plusieurs périodes par un problème de tarification sur une période lorsque la filtration est sans friction, ce qui est équivalent à supposer la propriété de martingale, qui est équivalente à supposer la cohérence des prix. Enfin, dans le troisième chapitre, nous présentons l'axiomatisation d'une classe particulière de règles de prix de Choquet, à savoir les règles de tarification dépendantes du rang qui supposent aussi l'absence d'arbitrage et la parité put-call (entre les options de vente et les options d'achat). Les règles de prix dépendantes du rang ont l'avantage d'être facilement calibrées car la mesure de probabilité non additive prend la forme de la probabilité objective distordue. Nous proposons donc une étude empirique de ces règles de prix dépendantes du rang par le biais d'une calibration paramétrique sur des données de marché afin d'explorer l'impact des frictions financières sur les prix. Nous étudions également la validité empirique de la parité put-call. En outre, nous étudions l'impact du délai d'expiration (valeur temps) et de la moneyness (valeur intrinsèque) sur la forme de la fonction de distorsion. Nous trouvons que les règles de prix dépendantes du rang qui en résultent sont toujours plus précises que la règle de référence (FTAP). Enfin, nous établissons un lien entre les frictions du marché et l'aversion au risque du marchéThis thesis aims to provide innovative theoretical and empirical methods for valuing securities to economics researchers, market makers, and participants, including brokers, dealers, asset managers, and regulators. We propose an extension of the Fundamental Theorem of Asset Pricing (FTAP) tailored to markets with financial frictions. Hence, our asset pricing methodologies allow for more tractable bid and ask prices, as observed in the financial market. This thesis provides both theoretical models and an empirical application of the pricing rule with bid-ask spreads.In our first chapter, we introduce two straightforward closed-form pricing expressions for securities in two-date markets, encompassing a variety of frictions (transaction cost, taxes, commission fees). This result relies on a novel absence of arbitrage condition tailored to the market with frictions considering potential buy and sell strategies. Furthermore, these asset pricing models both rely on non-additive probability measures. The first is a Choquet pricing rule, for which we offer a particular case adapted for calibration, and the second is a Multiple Priors pricing rule.In the second chapter, as a step toward generalizing our asset pricing models, we provide the necessary and sufficient conditions for multi-period pricing rules characterized by bid-ask spreads. We extend the multi-period version of the Fundamental Theorem of Asset Pricing by assuming the existence of market frictions. We show that it is possible to model a dynamic multi-period pricing problem with a one-stage pricing problem when the filtration is frictionless, which is equivalent to assuming the martingale property, which is equivalent to assuming price consistency.Finally, in the third chapter, we give the axiomatization of a particular class of Choquet pricing rule, namely Rank-Dependent pricing rules assuming the absence of arbitrage and put-call parity. Rank-dependent pricing rules have the appealing feature of being easily calibrated because the non-additive probability measure takes the form of a distorted objective probability. Therefore, we offer an empirical study of these Rank-Dependent pricing rules through a parametric calibration on market data to explore the impact of market frictions on prices. We also study the empirical validity of the put-call parity. Furthermore, we investigate the impact of time to expiration (time value) and moneyness (intrinsic value) on the shape of the distortion function. The resulting rank-dependent pricing rules always exhibit a greater accuracy than the benchmark (FTAP). Finally, we relate the market frictions to the market's risk aversion
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Aboulkacem, El Mehdi. "Infrastructures de transport urbain et frictions du marché du travail." Thesis, Lille 1, 2017. http://www.theses.fr/2017LIL12021/document.
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Cette thèse explore quelques facettes du rôle des infrastructures de transport urbain dans la fluidification des frictions du marché du travail causées par la dissociation spatiale entre les lieux de résidence et les opportunités d'emploi. Pour ce faire, elle est construite en trois chapitres.Dans le premier, nous construisons une série de fonctions d'appariement spatiales entre les travailleurs au chômage et les postes vacants qui tiennent compte de la dimension spatiale de la recherche d'emploi, qui dépendent des paramètres de l'infrastructure de transport et qui ne sont pas conditionnées par la structure de la ville dans laquelle l'appariement se déroule.Dans le second chapitre nous présentons un outil d'évaluation de politiques publiques novateur, utilisé ici pour mesurer l'impact de la performance de l'infrastructure et des services de transports publics franciliens sur les taux de chômage locaux et pour prédire l'impact du Grand Paris Express sur ces taux, mais qui peut être utilisé dans d'autres contextes et pour d'autres régions.Enfin, le troisième chapitre se penche sur les déterminants des distances domicile-travail parcourues par les travailleurs des ménages bi-actifs en région parisienne. L'objectif est de fournir des clés de compréhension de la demande de transport engendrée par l'augmentation constante de la part de ces ménages et de l'anticiper dans l'élaboration des politiques d'aménagement du territoire futuresWe explore in this thesis some aspects of the role played by the urban transport infrastructures in reducing the labor market frictions caused by the spatial separation between the places of residence and the job opportunities locations. To do so, this thesis is written in three chapters.In the first, we build a series of spatial matching functions linking jobless workers to vacant positions. These functions depend on the transport infrastructures parameters and are not conditional on the structure of the city in which the matching process occurs. In the second chapter we present an innovative public policy evaluation instrument used for measuring the impact of the Paris region transport infrastructures performances on the local unemployment rates and for predicting the impact of the Grand Paris Express on these rates. This instrument can be used in other contexts and for other regions. Last but not least, the third chapter analyses the determinants of the home-workplace distance of two-worker households' workers living in Paris region. The objective is to provide some clues to understand the transportation demand generated by the constant growth of the part of this kind of households and to anticipate it while designing the future planning policies
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Oh, Samil. "Trois essais sur les frictions du marché du travail, le commerce international et l'incertitude." Thesis, Cergy-Pontoise, 2018. http://www.theses.fr/2018CERG0972/document.
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Le marché du travail est une institution centrale dans toute économie moderne. En même temps, le marché du travail est caractérisé par une réglementation omniprésente. Une littérature récente et croissante étudie les conséquences d'une telle hétérogénéité dans les institutions du marché du travail. Jusqu'à présent, cependant, peu de travaux ont abordé les implications des rigidités du marché du travail pour la dynamique du travail induite par le commerce en se concentrant sur le secteur informel, ou les chocs de second moment dans un contexte d'économie ouverte. Le but de cette thèse est de répondre à ces questions.Le premier chapitre étudie l'impact des chocs d'incertitude dans une petite économie ouverte avec des frictions de recherche et d'appariement et l'entrée d'entreprises. Nous développons d'abord notre analyse empirique dans le contexte de l'économie coréenne, car toutes les dimensions du modèle sont pertinentes dans ce pays. Une augmentation de l'incertitude réduit la production, la consommation, l'investissement et le taux de recherche d'emploi, tout en augmentant le chômage et les séparations d'emploi. Nous complétons également les données empiriques existantes en examinant la dynamique des entreprises, le taux de change réel et le comportement du compte courant. Dans notre cadre théorique, nous illustrons de nouveaux mécanismes de transmission qui sont ignorés dans la littérature. Les mécanismes économiques vont au-delà de la simple addition de chaque caractéristique. Les frictions de recherche, l'entrée des entreprises et la dimension de l'économie ouverte interagissent fortement pour amplifier les effets des chocs d'incertitude et rendre le modèle cohérent avec les données empiriques.Le deuxième chapitre étudie comment les réformes fiscales contribuent à assurer une mondialisation équitable. Dans cet article, nous développons un modèle à deux zones: un pays développé et un pays émergent. Les deux domaines diffèrent selon la taille du secteur informel, caractérisé par un marché du travail plus flexible et une productivité plus faible. Notre analyse suggère que la libéralisation du commerce stimule l'activité économique et l'emploi dans les secteurs formel et informel. Cependant, cette expansion de l'emploi est biaisée vers le secteur informel, qui n'est pas soumis à la réglementation du travail et donc plus flexible. Par conséquent, la libéralisation du commerce entraîne une baisse de la qualité de l'emploi, car les travailleurs informels ne sont pas couverts par la législation du travail, la sécurité sociale et reçoivent des salaires moins élevés. Une réforme fiscale neutre en termes de budget, qui ferait passer le fardeau fiscal des taxes sur les salaires versées par les entreprises opérant dans le secteur formel à une taxe à la consommation, pourrait représenter une stratégie pour soutenir le secteur formel. Cependant, la formalisation se fait au prix d'une inégalité croissante des revenus entre travailleurs formels et informels.Le troisième chapitre évalue l'importance des institutions du marché du travail dans la transmission des chocs d'incertitude aux marchés du travail. En utilisant des VAR spécifiques aux pays dans les pays de l'OCDE, je constate qu'il y a une hétérogénéité considérable entre les réponses des taux de chômage aux chocs d'incertitude. Je fournis également des preuves que cette hétérogénéité peut être attribuée à la législation différentielle sur la protection de l'emploi (EPL). Les pays à faible niveau d'EPL subissent des augmentations de chômage plus graves que les pays à EPL élevé à la suite de chocs d'incertitude. EPL plus stricte neutralise la réaction du chômage, rendant plus coûteux le licenciement des travailleurs. De plus, le choc du second moment renforce ce mécanisme à travers le canal des options réelles. Sous l'irréversibilité et l'incertitude, les coûts de tir viennent avec un coût plus élevéThe labor market is a central institution in any modern economy. At the same time, the labor market is characterized by pervasive regulation. Across nations, the labor market is subject to minimum wages, hiring and firing restrictions, compulsory collective bargaining, etc. A recent and growing literature investigates the consequences of such heterogeneity in labor market institutions, studying how labor market rigidities affect the causes and consequences of policy changes. Thus far, however, few works have addressed the implications of labor market rigidities for trade-induced labor dynamics focusing on the informal sector, or the second moment shocks in an open economy setting. Important questions remain open for researchers and policymakers. The purpose of this thesis is to address these questions, studying the role of labor market frictions and its interaction with international trade and uncertainty.The first chapter investigates the impact of uncertainty shocks in a small open economy with search and matching frictions and firm entry. We first develop our empirical analysis in the context of the Korean economy, as all dimensions of the model are relevant in this country. An increase in uncertainty lowers output, consumption, investment and job finding rate, while raising unemployment and job separations. We also supplement the existing empirical evidence by looking at firm dynamics, real exchange rate and current account behavior. In our theoretical framework, we illustrate new transmissions mechanism that are ignored in the literature. Economic mechanisms go beyond the simple addition of each feature. Search frictions, firm entry and the open economy dimension actually strongly interact to amplify the effects of uncertainty shocks and make the model consistent with the empirical evidence.The second chapter studies how tax reforms help ensure a fair globalization. In this paper we develop a two-area model: a developed and an emerging country. The two areas differ according to the size of the informal sector, which is characterized by a more flexible labor market and lower productivity. Our analysis suggests that trade liberalization boosts economic activity and employment in both the formal and informal sector. However, this employment expansion is biased toward the informal sector, which is not subject to labor regulation and hence more flexible. Hence, trade liberalization leads to lower employment quality, as informal workers are not covered by the labor legislation, social security and receive lower paid. A budget-neutral tax reform switching the tax burden from payroll taxes paid by firms operating in the formal sector to a consumption tax may represent a strategy to support the formal sector. However, formalization comes at the cost of widening income inequality between formal and informal workers.The third chapter assesses the importance of labor market institutions in the transmission of uncertainty shocks to labor markets. Using country-specific VARs across OECD countries, I find that there is substantial cross-country heterogeneity in the responses of unemployment rates to uncertainty shocks. I also provide evidence that this heterogeneity can be attributed to differential employment protection legislation (EPL). Low EPL countries suffer more severe rises in unemployment compared to high EPL countries following uncertainty shocks. Stricter EPL mutes the reaction of unemployment, making it more costly to lay workers off. Moreover, the second moment shock reinforces this mechanism through the real options channel. Under irreversibility and uncertainty, firing costs come with a bigger cost. On the other hand, the role of other labor market characteristics is ambiguous
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Bocognano, Laurène. "Cultural transmission, education and employment with labor market frictions." Thesis, Aix-Marseille, 2020. http://www.theses.fr/2020AIXM0128.
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Cette thèse évalue les effets combinés des valeurs culturelles et des frictions du marché du travail sur les choix d'éducation des individus et leur comportement au chômage. Le premier chapitre propose une explication à la reproduction sociale. J'utilise un modèle de générations imbriquées où les parents transmettent des valeurs plus ou moins favorables à l'emploi et où l'enfant choisit son éducation et cherche un emploi. La transmission se fait sous information imparfaite sur les capacités scolaires de son enfant. Dans les familles privilégiées, les parents ne doutent pas de la réussite de leur progéniture, et transmettent une forte valeur pro-emploi. Ce mécanisme accroît l'immobilité sociale. Le deuxième chapitre montre comment calculer l'assurance-chômage dans un cas où les préférences endogènes sont représentées par un choix optimal d'une estime de soi au travail qui peut être complémentaire ou substituable au salaire. En négligeant la nature endogène et spécifique à l'état de l'estime de soi, une approche de statistiques suffisantes peut appeler, à tort, à une expansion de l'assurance-chômage. Le troisième chapitre analyse la relation entre l'éthique au travail et la décision de toucher des prestations en cas de chômage avec un modèle de recherche d'emploi où les parents transmettent une estime de soi au travail. Augmenter les allocations chômage ou baisser le coût du recours augmente la probabilité de toucher des prestations, tandis que diminuer le coût de recherche d'emploi diminue les taux de chômage et de participation via une augmentation de l'éthique au travail (pour un risque chômage plus faible), entraînant une stigmatisation du chômageThis dissertation assesses the combined effects of cultural values and labor market frictions on individuals' educational investments and unemployment behaviors. The first chapter proposes an explanation to social reproduction. I use an overlapping generations model where parents transmit values more or less favorable to employment and the child chooses education and looks for a job. Transmission occurs through imperfect information about their offspring's scholastic ability. In privileged families, parents do not doubt about their offspring's success on the labor market, and transmit a strong pro-employment value. I find that this mechanism increases social immobility.The second chapter assesses how to compute optimal UI in a case where endogenous preferences are represented by an optimal choice of self-esteem at work which can either be complementary or substitutable to work income. While neglecting the state-specific and endogenous nature of self-esteem weights, a sufficient statistics approach may wrongly call for UI expansions. The third chapter analyzes the relationship between inherited work ethic and the decision to take up benefits in case of unemployment with a search model where parents transmit self-esteem at work to their offspring. An increase in non employment income or a decrease of the claiming cost increase the probability of taking benefits up in the case of unemployment, while a decrease in the searching cost decreases the unemployment rate and the take-up rates. This last result comes from an increase of employment self-esteem when the unemployment risk is lower, which itself leads to an increase in unemployment stigma
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Guigue, Etienne. "Market Power and Frictions in Supply Chains." Electronic Thesis or Diss., Institut polytechnique de Paris, 2023. http://www.theses.fr/2023IPPAG009.
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Cette thèse vise à mieux comprendre le rôle du pouvoir de marché et de la concurrence imparfaite dans les relations entre fournisseurs et acheteurs opérant dans des chaînes de valeur mondiales et nationales entrelacées. Cette recherche s'appuie sur des outils empiriques et théoriques, appliqués à l'industrie laitière française et aux industriels importateurs français.Le Chapitre 1 propose une nouvelle méthodologie pour estimer séparément le pouvoir de marché à l'achat et à la vente, appliquée aux transformateurs de produits laitiers en France. Ces entreprises exercent du pouvoir de marché à l'achat lorsqu'elles achètent du lait cru et à la vente lorsqu'elles commercialisent des produits laitiers. L'analyse est basée sur des données individuelles d'entreprises, où les prix et les quantités de lait cru par origine côté achat et par produit côté vente sont observés de 2003 à 2018. Les marges totales sont estimées via une approche « fonction de production ». L'existence d'un produit de base (i) substituable en tant qu'intrant ou en tant que produit, et (ii) échangé sur les marchés mondiaux où les transformateurs laitiers français sont preneurs de prix, permet ensuite d'estimer séparément les marges de chaque entreprise à l'achat, par origine, et à la vente, par produit. Les résultants indiquent que les entreprises laitières achètent en moyenne le lait cru à un prix inférieur de 16% à sa contribution marginale à leurs bénéfices, et vendent les produits laitiers à un prix supérieur de 41% à leurs coûts marginaux. Une analyse de la transmission des chocs de coûts des agriculteurs et des transformateurs sur la chaîne d'approvisionnement révèle que ces chocs sont partiellement absorbés par les transformateurs. En ajustant leurs marges, les transformateurs lissent les variations de revenu des agriculteurs mais détournent en moyenne 65% de leurs subventions.Le Chapitre 2 analyse l'impact des quotas de production et de leur suppression progressive sur le marché du lait en France, montrant que les quotas ont généré deux types de distorsions. Premièrement, en fixant mécaniquement les parts de production des départements français à leurs niveaux pré-quotas (1984), les quotas ont stoppé une concentration spatiale naturelle pendant environ 25 ans, un processus qui a repris après le début du retrait progressif des quotas en 2008. Deuxièmement, le système de quotas a favorisé la croissance des petites exploitations mais limité l'expansion des plus grandes, freinant ainsi des inégalités jusqu'alors croissantes entre fermes, mais au prix d'une distorsion de l'écrémage concurrentiel des exploitations laitières. Enfin, le processus de rattrapage dans la sélection des exploitations post-quotas est intervenu plus ou moins tôt dans les départements, en fonction de la contrainte imposée par les quotas au niveau local. Ces observations sont rationalisées à l'aide d'un modèle de concurrence parfaite entre exploitations hétérogènes.Le Chapitre 3 quantifie le pouvoir de marché des entreprises à l'achat d'intrants et évalue ses effets agrégés. Le chapitre présente une stratégie empirique visant à estimer le pouvoir de marché à l'achat de produits intermédiaires importés ou achetés localement, sans imposer d'hypothèses sur d'autres marchés d'intrants, et utilisant des données standard de commerce international et de production. Ce chapitre montre que les entreprises manufacturières françaises exercent une marge moyenne à l'achat de 1,49 sur les intrants importés et de 1,59 sur les intrants achetés localement, révélant un pouvoir de marché à l'achat significatif sur les deux types d'intrants. Les conséquences en termes de bien-être sont ensuite explorées avec un modèle d'équilibreThis dissertation aims to better understand the role of market power and competition frictions between suppliers and buyers in intertwined global and national supply chains. This research leverages empirical and theoretical tools applied to the French dairy industry and French manufacturing importers.Chapter 1 suggests a new methodology to separately estimate firm buyer and seller power, which is important for policy-making but challenging, and apply it to French dairy processors. These firms exert buyer power when purchasing raw milk, and seller power when marketing dairy products. The analysis is based on plant-level data on dairy firms, with observations on prices and quantities of raw-milk input by origin and output by product from 2003 to 2018. Total margins are estimated relying on a production function approach. The existence of a commodity, (i) substitutable as an input or as an output, and (ii) exchanged on global markets where firms are price-takers, then allows separately estimating firm-origin markdowns and firm-product markups. The methodology can also be useful in other contexts, with more limited data. Markdown estimates imply that dairy firms on average purchase raw milk at a price 16% below its marginal contribution to their profits, while markup estimates indicate that firms sell dairy products at a price exceeding their marginal costs by 41%. This chapter also analyzes how exogenous farmer and processor cost shocks pass through the supply chain. Processors partially absorb such shocks by adjusting markups and markdowns, thus smoothing variations in farmer revenues. It further implies that 65% of subsidies are currently diverted from farmers due to processor buyer power.Chapter 2 analyzes the impact of production quotas and their progressive removal in the French milk market, showing that production quotas generated two types of distortions. First, by mechanically fixing production shares across French départements at their pre-quota (1984) level, quotas stopped a natural spatial concentration for about 25 years, a process that restarted right after the start of the progressive quota removal in 2008. Second, the design of the quota system spurred the growth of small farms while constraining the expansion possibilities of larger farms. This redistributive scheme thus successfully refrained inequalities among farms growing until then, yet at the cost of distorting the competition-led cream-skimming of farms. Results finally show how the catching-up process in farm selection following the quota removal intervened more or less early across départements, depending on the stringency implied by quota constraints at the local level. These observations are rationalized with a simple model of perfect competition between heterogeneous farms.Chapter 3 quantifies buyer power in input trade and evaluates its aggregate effects. The developed empirical strategy for estimating importer buyer power from standard trade and production data does not rely on assumptions about other input markets. The results show that French manufacturing firms exert an average markdown of 1.49 on imported inputs and of 1.59 on domestically purchased inputs, revealing their significant buyer power in both markets. The welfare implications are then explored using an equilibrium model
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Rastouil, Jeremy. "Three essays on labor market frictions under firm entry and financial business cycles." Thesis, Bordeaux, 2019. http://www.theses.fr/2019BORD0228.
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Durant la grande récession, les interactions entre fluctuations du prix de l’immobilier, du travail et de l’entrée des firmes sur le marché des biens, ont mis en avant l’existence de relations étroites entre ces marchés. Le but de cette thèse est de mettre en lumière les interactions entre le marché du travail et le marché des biens ainsi que des cycles financiers, en utilisant les récents progrès des modèles DSGE. Dans le premier chapitre, nous avons trouvé un fort rôle joué par la création de firmes dans l’amplification des dynamiques de l’emploi. En introduisant le mécanisme du modèle de Diamond-Mortensen-Pissarides sur le marché du travail, nous avons pu étudier sous un nouvel angle les fluctuations du taux de marge des firmes. Comparé aux travaux théoriques utilisant un marché du travail sans frictions, nous avons trouvé un taux de marge moins contracyclique dû au coût marginal acyclique d’un modèle avec frictions. De plus, le rôle accordé à la création de firmes dans la détermination du taux de marge est moins important que dans les papiers précédents. Dans le second chapitre, nous avons lié la capacité d’endettement des ménages avec leur situation sur le marché de l’emploi. Grâce à cette microfondation, les nouveaux arrivants sur le marché du travail entrainent un plus haut niveau de dette immobilière tandis que ceux qui perdent leurs emplois sont exclus du marché du crédit. En conséquence, le ratio LTV devient endogène et répond de manière procyclique aux fluctuations de l’emploi. Nous avons montré que cette modélisation était empiriquement fondée et résout les anomalies d'une contrainte de crédit standard. Dans le dernier chapitre, nous avons étendu l’analyse précédemment effectuée en intégrant des firmes qui s’endettent dans le but d’obtenir un cycle financier plus complet. Le premier résultat est qu’une contrainte de crédit pour les firmes intégrant à la fois les biens immobiliers, le capital et la masse salariale permet de mieux rendre compte des fluctuations sur le marché du travail comparativement aux contraintes n’intégrant qu’une partie de ces trois composantes. Le second résultat met en évidence le rôle des fluctuations immobilières et du crédit sur l’emploi. Les deux derniers chapitres ont d’importantes implications pour les politiques économiques. Une réforme structurelle du marché du travail visant à le déréguler entraine une forte hausse de la dette immobilière pour les ménages ainsi que du prix de l’immobilier et une augmentation moindre de la dette des firmes. Notre approche révèle qu’une politique macroprudentielle visant à restreindre la capacité d’emprunt des ménages conduit à des effets positifs à long terme pour l’économie tout en limitant les effets sur le marché immobilier (dette et prix). A l’inverse, une politique macroprudentielle visant à réduire l’emprunt des entreprises conduit à l’effet inverse avec des effets négatifs à long terme pour l’économieDuring the Great Recession, the interactions between housing, labor and entry highlight the existence of narrow propagation channels between these markets. The aim of this thesis is to shed a light on labor market interactions with firm entry and financial business cycles, by building on the recent theoretical and empirical of DSGE models. In the first chapter, we have found evidence of the key role of the net entry as an amplifying mechanism for employment dynamics. Introducing search and matching frictions, we have studied from a new perspective the cyclicality of the mark-up compared to previous researches that use Walrasian labor market. We found a less countercyclical markup due to the acyclical aspect of the marginal cost in the DMP framework and a reduced role according to firm's entry in the cyclicality of the markup. In the second chapter, we have linked the borrowing capacity of households to their employment situation on the labor market. With this new microfoundation of the collateral constraint, new matches on the labor market translate into more mortgages, while separation induces an exclusion from financial markets for jobseekers. As a result, the LTV becomes endogenous by responding procyclically to employment fluctuations. We have shown that this device is empirically relevant and solves the anomalies of the standard collateral constraint. In the last chapter, we extend the analysis developed in the previous one by integrating collateral constrained firms in order to have a more complete financial business cycle. The first result is that an entrepreneur collateral constraint integrating capital, real commercial estate and wage bill in advance is empirically relevant compared to the collateral literature associated to the labor market which does not consider these three assets. The second finding is the role of the housing price and credit squeezes in the rise of the unemployment rate during the Great Recession. The last two chapters have important implications for economic policy. A structural deregulation reform in the labor market induces a significant rise in the debt level for households and housing price, combined with a substantial rise of firm debt. Our approach allows us to reveal that a macroprudential policy aiming to tighten the LTV ratio for household borrowers has positive effects in the long run for output and employment, while tightening LTV ratios for entrepreneurs leads to the opposite effect
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Pappadà, Francesco. "Effets au niveau agrégé de l'hétérogénéité des firmes et des frictions sur le marché du crédit." Paris 1, 2011. http://www.theses.fr/2011PA010020.
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Les conclusions générales de cette thèse peuvent être synthétisées en trois points. Le chapitre 1 montre que la taille relative de la marge intensive et de la marge extensive de l'ajustement des déséquilibres mondiaux des comptes courants sont déterminées par la dispersion de la taille des firmes. Le modèle calibré sur la dispersion de la taille des firmes observée aux Etats-Unis montre que la marge intensive est le canal prédominant de l'ajustement du compte courant. L'effet amortissant de la marge extensive sur l'ajustement des taux de change a une grandeur significative seulement pour des niveaux de dispersion des tailles des firmes très faibles. Le chapitre 2 montre que la cessation d'activité des entreprises génère un effet d'amplification des chocs macroéconomiques. A l'aide d'un modèle théorique, nous montrons comment les contraintes de crédit conduisent à amplifier l'effet des récessions sur la production agrégée en fragilisant les entreprises. Les fluctuations du taux de sortie sont exacerbées: la récession conduit certaines firmes, qui auraient survécu en l'absence de contraintes de crédit, à liquider leur activité. Dans le chapitre 3, nous utilisons les données sur l'évasion fiscale de l'Agenzia delle Entrate pour montrer que la corrélation entre l'évasion fiscale et le développement financier est négative et significative. Nous proposons une explication pour la corrélation négative entre le développement financier et l'évasion fiscale. Les frictions sur le marché du crédit réduisent le bénéfice marginal de l'investissement dans le secteur formel, et facilitent ainsi l'investissement dans le secteur informel.
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Guglielminetti, Elisa. "Empirical and theoretical implications of frictional labor markets." Thesis, Paris, Institut d'études politiques, 2015. http://www.theses.fr/2015IEPP0034.
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J’utilise des modèle de search comme point de départ de mon analyse, en examinant l'impact des frictions d'un point de vue soit théorique soit empirique. Dans le Chapitre 1 j’analyse les effets de l’incertitude sur la macroéconomie. Les estimes empiriques montrent que l’incertitude a un impact négatif sur l’économie et que le marché du travail est un important canal de transmission. Un modèle d’équilibre général avec frictions DMP est capable de reproduire les faits observés. Dans le Chapitre 2 j’utilise un Time Varying Parameter SVAR avec volatilité stochastique pour investiguer les propriétés de la création d’emploi aux Etats Unis et leur variation dans le temps. Les estimes indiquent que la volatilité dépend largement des chocs de demande et de prix. Les postes de travail réagissaient négativement aux chocs technologiques jusqu’au début des années 90. Le Chapitre 3 intègre la dimension spatiale dans un modèle de search. Cela permet d'expliquer quelques régularités observées dans des données Autrichiens: i) l’existence d’une frontière de réserve entre salaire est distance; ii) le changement de stratégie de recherche d’emploi; iii) l'effet décourageant des d’allocations chômage. Dans le Chapitre 4 je présente un modèle qui explique la sélection des nouvelles embauches entre contrats à court et à long terme. En exploitant une base de données italienne, on trouve que la probabilité d’obtenir un contrat permanent dépend négativement du degré de mismatch entre l'éducation du travailleur et l'occupation. En outre, les réformes qui libéralisent le contrats à durée déterminée encouragent leur utilisation mais ils ont effets non-linéaires sur le taux de chômageIn this thesis I take the search and matching framework as the starting point of my analysis to investigate several aspects of the labor market. In Chapter 1, I explore the consequences of uncertainty on the macroeconomy . The empirical analysis shows that uncertainty has a detrimental effect on the aggregate economy and that job creation is an important channel of transmission. The empirical findings are then rationalized through a DSGE model incorporating the DMP setup and featuring stochastic volatility. In Chapter 2, I study the time-varying characteristics of job creation in the US. The econometric setup is a Time-Varying Parameter SVAR (TVP-SVAR) with stochastic volatility. The identification strategy is based on a DSGE model with a frictional labor marketIn Chapter 3, I extend the standard framework to take into account the spatial dimension of job search. Austrian data show the existence of a trade- off between wage and commute time. They also uncover complex patterns in the dynamics of exits from unemployment. Cox-regressions further show that the level of unemployment benefits has a strong discouraging effect on job search. In Chapter 4, I use a random search model to study the sorting of new hires into open-ended and fixed-term contracts. The co-existence of these two types of contracts is explained by match heterogeneity. The match productivity is interpreted as the fit of worker's skills to task requirements. This hypothesis is supported by matched employer-employee data from a large Italian region
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Cerdan, Ophelie. "La nature des investissements en capital humain et le design des institutions du marché du travail." Thesis, Aix-Marseille 2, 2011. http://www.theses.fr/2011AIX24020.
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L'éducation est un investissement qui trouve son rendement sur le marché du travail.Cependant, les frictions à l'œuvre sur ce marché affectent aussi bien le niveau que la nature des investissements éducatifs. Dans le même temps, les compétences acquises lors de la scolarité conditionnent le design des institutions du marché du travail.Nous proposons trois chapitres qui examinent chacun une question particulière.Le premier présente un modèle de mismatch sur le marché du travail où le degré d'inadéquation entre travailleurs et emplois est endogène : il dépend des efforts éducatifs (qui réduisent le mismatch) et des investissements technologiques (qui l'augmentent). Nous examinons l'impact de l'incertitude concernant le futur partenaire de travail, de l'hétérogénéité des travailleurs vis-à-vis de leur capacité scolaire, et de l'aversion au risque.Le deuxième construit un modèle d'appariement avec spécialistes et généralistes dans lequel la proportion de spécialistes est endogène. La nature du capital humain détermine le nombre de files d'attentes dans lequel le travailleur peut prospecter ainsi que son rang dans chacune d'elles. L'éducation véhicule plusieurs externalités : les spécialistes favorisent la création d'emplois dans chaque secteur ; les généralistes améliorent l'efficience de la technologie d'appariement mais aggravent le problème de coordination des firmes. Nous calibrons le modèle sur données agrégées pour 20 pays de l'OCDE. L'auto-sélection s'avère toujours inefficace : taxer la formation professionnelle pourrait réduire le taux de chômage de plus d'un point de pourcentage.Le troisième étudie le design de l'assurance chômage dans un contexte où les travailleurs diffèrent quant à la nature de leur capital humain. Nous montrons que selon le scénario retenu pour la gestion de la caisse d'assurance, la proportion de spécialistes peut conduire à diminuer ou accroître le taux de remplacement de l'indemnité chômage optimaleEducation is an investment that has its return on the labor market. However, frictions at work in this market affect both the level and the nature of educational investments. At the same time, the skills gained during schooling time determine the design of labor market institutions.This thesis is made of three chapters examining, each of them examines a particular issue.The first one presents a mismatch model on labor market where the efficiency of the assignment mechanism is endogenous: it depends on educational efforts (which reduce the mismatch) and on technological investments (which increases it). We examine the impact of uncertainty regarding the future work associate, of the worker's heterogeneity toward scholastic ability, and of risk aversion.In the second one we build a two-sector matching model with generalists and specialists, in which the proportion of specialists is endogenous. The nature of human capital determines the number of job queues in which worker can candidates as well as its rank in each of them. Self-selection in education type leads to three main externalities: specialists enhance job creation in each sector; generalists improve the efficiency of the matching technology, but nevertheless exacerbate firm's coordination problems. We calibrate the model on aggregate data for 20 OECD countries. Self-selection is always inefficient: taxing vocational education, to reduce the proportion of specialists down the efficient level, could reduce unemployment rates by more than one point of percentage.The third one studies the unemployment insurance scheme in a context where workers have different kind of human capital. We show that, depending on the scenario chosen for the management of the insurance fund, the proportion of individuals with specific human capital can lead either to a decrease or to an increase of the replacement rate of the optimal unemployment benefit
Books on the topic "Frictions de marché"
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Cederlöf, Gunnel, and Willem van Schendel. Flows and Frictions in Trans-Himalayan Spaces. Nieuwe Prinsengracht 89 1018 VR Amsterdam Nederland: Amsterdam University Press, 2022. http://dx.doi.org/10.5117/9789463724371.
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Flows and Frictions in Trans-Himalayan Spaces traces movements and connections in a region known for its formidable obstacles to mobility. Eight original essays and a conceptual introduction engage with questions of networks and interconnection between people across a bordered landscape. Mobility among the extremely varied ecologies of south-western China, Myanmar and north-eastern India, with their rugged terrain, high mountains, monsoon-fed rivers and marshy lowlands, is certainly subject to friction. But today, harsh political realities have created hard borders and fractured this trans-Himalayan terrain. However, the closely researched chapters in this book demonstrate that these borders have not prevented an abundance of movements, connections and flows. Mobility has always coexisted with friction here, but this coexistence has been unsettled, giving this space its historical shape and its contemporary dynamism. Introducing the concept of the ‘corridor’ as an analytical framework, this collection investigates mobility and flows in this unique socio-political landscape.
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Minerals, Metals and Materials Society. Meeting. Friction stir welding and processing II: Proceedings of symposium sponsored by the Shaping and Forming Committee of the Materials Processing & Manufacturing Division (MPMD) of TMS (The Minerals, Metals & Materials Society : 2003 TMS Annual Meeting, San Diego, California, March 2-6, 2003. Warrendale, PA: TMS (The Minerals, Metals & Materials Society), 2003.
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Institution of Mechanical Engineers (Great Britain). Power Industries Division. and Nihon Kikai Gakkai, eds. Combustion engines: Reduction of friction and wear : 18-19 March 1985, 1 Birdcage Walk, Westminster, London SW1. London: Published for the Institution by Mechanical Engineering Publications, 1985.
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V, Jata K., Minerals, Metals and Materials Society. Shaping and Forming Committee., Minerals, Metals and Materials Society. Meeting, and TMS Symposium on Friction Stir Welding (3rd : 2005 : San Francisco, Calif.), eds. Friction stir welding and processing III: Proceedings of a symposia [sic] sponsored by the Shaping and Forming Committee of the Materials Processing and Manufacturing Division (MPMD) of TMS (The Minerals, Metals & Materials Society), 2003 TMS Annual Meeting, San Diego, California, March 2-6, 2003. Warrendale, Pa: TMS, 2005.
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Mishra, Rajiv S. Friction stir welding and processing VI: Proceedings of a symposium sponsored by the Shaping and Forming Committee of the Materials Processing & Manufacturing Division of TMS (The Minerals, Metals & Materials Society) : held during the TMS 2011 Annual Meeting & Exhibition, San Diego, California, USA, February 27-March 3, 2011. Hoboken, N.J: John Wiley & Sons, 2011.
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A, Smidt F., Blau P. J, ASM International. Washington, D.C. Chapter., ASM International. Wear Resistant Materials Group., United States. National Bureau of Standards., and Conference on Engineered Materials for Advanced Friction and Wear Applications (1988 : Gaithersburg Md.), eds. Engineered materials for advanced friction and wear applications: Proceedings of an international conference, Gaithersburg, Maryland, USA, 1-3 March, 1988. [Metals Park, Ohio]: ASM International, 1988.
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Symposium on "Celestial Mechanics" (34th 2002 Kanagawa, Japan). Dynamical friction strikes back?: Proceedings of the 34th Symposium on Celestial Mechanics, March 11-13, 2002 at Hakone-Onsen, Kanagawa, Japan = Imasara rikigaku teki masatsu? : Hakone tentai rikigaku N tai rikigaku kenkyūkai shūroku : Heisei 13-nen 3-gatsu 11-nichi-13-nichi, Kanagawa-ken Ashigara-gun Hakone-machi Kyōra Seiun-sō. Edited by Kokubo E, Ito T, and Arakida H. [Japan?: s.n., 2002.
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Gajewski, Jean-François. Frictions et asymétrie d'information sur les marchés d'actions. Economica, 2000.
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Combustion engines - reduction of friction and wear: [papers read at the conference held at the Institution of Mechanical Engineers, London on 18-19 March 1985]. London: Published for the Institution of Mechanical Engineers by Mechanical Engineering, 1985.
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Preston, Daniel, ed. The Papers of James Monroe, Volume 7. ABC-CLIO, LLC, 2020. http://dx.doi.org/10.5040/9798400695117.
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The 605 documents presented in Volume 7 of The Papers of James Monroe date from April 1814, the midpoint of Monroe's term as secretary of state under President James Madison, to March 1817, just prior to his inauguration as president. Volume 7 opens in the midst of the War of 1812, documenting Monroe's role as military adviser to President Madison during an ill-fated defense of Washington in August 1814, his appointment as secretary of war in September 1814, and his return to the State Department in March 1815, when he began the work of normalizing relations with the European nations after the end of the Napoleonic wars. Relations with Great Britain remained uneasy, but Monroe reduced friction by negotiating the 1817 Rush-Bagot Treaty, which led to disarmament of the Great Lakes. Numerous documents detail the ill will between the United States and Spain caused by the war, disagreement over possession of Florida, and the revolutions in Spain's American colonies. The volume also addresses the presidential election of 1816. Monroe, in line with the accepted practice at the time, avoided any overt acts that would indicate he was seeking the office. Correspondence with friends and confidants and several campaign essays written by Monroe nevertheless reveal a strategy of a quiet campaign to garner support for his candidacy.
Book chapters on the topic "Frictions de marché"
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Moron, J. W., and M. Klosek. "Remarks on the Nature of the High Internal Friction Peak near Tg in Glassy Alloys." In March 16, 317–22. De Gruyter, 1988. http://dx.doi.org/10.1515/9783112480823-039.
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Wyss, Marco. "A French Prerogative." In Postcolonial Security, 187–222. Oxford University Press, 2021. http://dx.doi.org/10.1093/oso/9780198843023.003.0007.
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In contrast to Nigeria, there had not been any real planning for the creation of national armed forces in Côte d’Ivoire in the late 1950s. Houphouët-Boigny relied on the protection of the French-led Community army, and de Gaulle continued to expect Ivorian contributions in manpower. The situation changed, however, in the wake of the abrupt end of the Community and Houphouët-Boigny’s sudden march towards independence. Despite Franco-Ivorian frictions during the transfer of power, however, the Ivorian leader expected and could eventually count on French military assistance. But France’s exclusive military assistance role nevertheless came to be challenged from unexpected quarters, with the Ivorian civic service being built up with Israeli assistance. But even though the French were at the time probably the Israelis’ closest Western security partners, and retained control of the purely military assistance to the Ivorian armed forces, they actively and successively sought to reduce Israel’s involvement.
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Reynolds, Robert G. "The Impact of Raiding on Settlement Patterns in the Northern Valley of Oaxaca: An Approach Using Decision Trees." In Dynamics in Human and Primate Societies. Oxford University Press, 2000. http://dx.doi.org/10.1093/oso/9780195131673.003.0016.
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A growing body of data indicates that armed conflict played a role in the creation of complex societies such as chiefdoms and states (Wright 1984; Spencer 1998). For example, according to Wright (1977:382), "most ethnographically reported chiefdoms seem to be involved in constant warfare," and large chiefdoms grew by absorbing their weaker neighbors. Marcus and Flannery suggest that warfare was often used to create a state out of rival chiefdoms: . . . We do not believe that a chiefdom simply turns into a state. We believe that states arise when one member of a group of chiefdoms begins to take over its neighbors, eventually turning them into subject provinces of a much larger polity. (Marcus and Flannery 1996:157) . . . As an example of this process, the authors cite Kamehameha's creation of a Hawaiian state out of five to seven rival chiefdoms between 1782 and 1810. They suggest that something similar happened in the Valley of Oaxaca, Mexico, when a chiefdom in the Etla region seized the defensible mountain top of Monte Albán and began systematically subduing rival chiefdoms in the southern and eastern parts of the valley. If this is the case, there should be a point in the sequence when considerations of defense began to influence settlement choice. In this chapter, our goal is to provide a preliminary description of our efforts in testing the suitability of this model to the Oaxacan case, and its potential use as the basis for a more general model of state formation. In order to test this hypothesis we need some way to operationalize it in terms of the archaeological record in the Valley of Oaxaca. The key phases of the model can be expressed as follows: 1. An early period in which raiding was minimal, and variables relevant to successful agriculture predominate in settlement choices. 2. A gradual rise in friction between social groups prior to state formation. This friction can be represented by archaeological evidence for raiding, the principle form of warfare in tribes and chiefdoms.
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Del Percio, Enrique. "Argentina: The Philosophical Resistance to the Conquest of the Soul1." In A Post-Neoliberal Era in Latin America?, 159–76. Policy Press, 2019. http://dx.doi.org/10.1332/policypress/9781529200997.003.0008.
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In 1976, a terrible dictatorship was established in Argentina, even before Foucault claimed with crystal clarity that the fundamental difference between classical liberalism and neoliberalism was the substitution of the homo economicus −related to the exchange− by the homo economicus as entrepreneur of himself (lecture delivered on 14 March 1979); and also before Margaret Thatcher (in Ronald Butt’s interview, Sunday Times, 3 May 1981) confirmed Foucault´s analysis stating that: “Economics are the method; the object is to change the heart and soul”. In the same year, Milton Friedman received the Nobel Prize in Economics. The explicit purpose of the Military Junta was to promote a profound cultural transformation, based on the premise that the causes of the alleged “underdevelopment” were not so much economical but cultural and political. Nevertheless, as García Delgado and Molina (2006) pointed out, the problem is not related to a sort of inevitable structural poverty, due to the culture of our people. It is a matter of a decline in society, produced by the policy orientation of the dictatorship. Until then, the income distribution was similar to that of the countries from the Southern Europe with an almost frictional unemployment. Until the coup d’état, Argentina had a poverty rate of 8% and the best distributive structure of income in Latin America. However, 1976 was a turning point; the surge of the neoliberal model promoted a process of over-indebtedness, wealth concentration, unrestricted opening of markets with an unfavourable exchange rate for national industry, labour flexibilization, with the insertion in a competitive globalization of “savage capitalism” that “strengthened the asymmetries and transfers of resources from the periphery to the centre. This concept differs from thinking about inequality as a problem related to culture, corruption and poor institutional quality” (García Delgado, 2006).Despite the overwhelming adverse evidence, it is still a commonplace to blame all the ills of our society on that culture, the maximum expression of which would be Peronism. In fact, the great majority of disappeared people during the dictatorship were Peronist political, trade union and social leaders. The motto of the Ministry of Economics during the dictatorship was “towards a change of mentality”. The current Argentine situation, in terms of advances of neoliberalism as well as resistances to it, cannot be understood without referring to the dictatorship. In Poratti words, “the coup d’état of 1976 does not only put an end to a government, a political system and project, but also to a 'world' in which Argentinians were living at least from the independence project of 1810. In those days, there was not an abrupt differentiation between generations and, in many aspects, people could identify themselves, diachronically, with a historical line beyond the particular generational characteristics” (Various Authors, 2009).These aspects go along with others that appeared in other areas, such as the implementation of new computer and communication technologies and, as a consequence, individual and social fragmentation. The impact of these technologies on daily life was decisive to the emergence of what some authors, like Sloterdijk (2002), called “mass individualism.” No doubt, this is a necessary aspect to explain the rise of the neoliberal subjectivity in developed countries. Yet, in Argentina, the existence of political, social, trade-union and ecclesiastical movements based on popular roots, with solidarity as a fundamental value, hampered the conquest of the “heart and soul” in 1976; and they are still now an obstacle to be overcome by sectors interested in imposing a neoliberal model. It is impossible to explain any isolated phenomenon of popular resistance to the hegemonic attempts from neoliberalism without analysing the common conceptions and understandings found in Argentina. Indeed, the popular culture substrate in Argentina is made up, mainly, by the confluence of different cultures: Andean, Guaraní Indians, Afro and Criollo (native). All of them are characterized by their relational and solidarity conceptions, intrinsically opposed to a subjectivity that conceives the individual as an entrepreneur of himself/herself.
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"Kuchma first became president on 10 July 1994. Friction between president and parliament has been a factor (as will be discussed below) in hindering economic reform. Kuchma has been re-elected, winning the second round of the presidential election (held on 14 November 1999) more comfortably than anticipated. His rival, Petro Simonenko (head of the Communist Party), was perceived as too inclined to state regulation of the economy and too close to Russia. Nevertheless, OSCE expressed considerable concern about the way Kuchma ran his campaign, e.g. the use of the state to manipulate the media. The general election of 29 March 1998 did not result in a sea change in the balance of forces in parliament: leftist forces remained the strongest but without a majority; a substantial centre persisted; nationalist forces, however, weakened somewhat. Parties have generally been strengthened. Kuchma hoped for a more constructive relationship with parliament and for a less geographi-cally split country." In The Countries of the Former Soviet Union at the Turn of the Twenty-First Century, 130–40. Routledge, 2004. http://dx.doi.org/10.4324/9780203647547-7.
Full textConference papers on the topic "Frictions de marché"
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Santos, Andrew, Ishan Srivastava, Leonardo Silbert, Jeremy Lechman, and Gary Grest. "Granular rheology with sliding rolling and twisting friction." In Proposed for presentation at the American Physical Society 2021 March Meeting held March 15-19, 2021. US DOE, 2021. http://dx.doi.org/10.2172/1856090.
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Lie, Halvor, Decao Yin, and Stergios Liapis. "On the Torsional Friction of Freely Rotating Short Fairing." In ASME 2014 33rd International Conference on Ocean, Offshore and Arctic Engineering. American Society of Mechanical Engineers, 2014. http://dx.doi.org/10.1115/omae2014-24591.
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Vortex-induced vibrations (VIV) model tests were carried out by Shell on a 38 m flexible pipe at the MARINTEK Ocean Basin in March 2011, Trondheim. As part of the model test campaign, the pipe with short fairings under two different torsional friction conditions between riser and fairings was tested in uniform currents. Test with ‘high’ friction show small responses, tests with ‘low’ friction show distinct large responses, even though, the spectra analysis shows that the responses seem to be dominated by vortex induced forces. Decay tests were carried out on a riser section with fairings to further investigate the torsional friction effect. Friction coefficients were calculated by ‘Coulomb damping model’, which is proved to be a suitable model for fairing-riser friction. The friction coefficients could be directly used to determine the damping ratio and implemented in numerical models. Such decay tests are especially useful to design, manufacture and install fairings in order to achieve a proper friction level and avoid unstable responses such as galloping.
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Clemmer, Joel, Ishan Srivastava, Jeremy Lechman, and Gary Grest. "Impact of loading geometry on steady-state flow of frictional granular packings." In Proposed for presentation at the American Physical Society March Meeting held March 15-19, 2021 in Virtual, United States. US DOE, 2021. http://dx.doi.org/10.2172/1882039.
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"New Correlations for Friction Factor and Nusselt Number Prediction for Laminar Flow in a Circular Duct having only Spiral Corrugations & only Twisted Tapes with Oblique Teeth." In March 2017 Singapore International Conferences. EAP, 2017. http://dx.doi.org/10.17758/eap.u0317218.
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Kumar Yadav, Pawan, Sandesh Thapa, Xiao Han, Cecilia Richmond, and Ning Zhang. "Investigation of the Effects of Wetland Vegetation on Coastal Flood Reduction Using Hydrodynamic Simulation." In ASME/JSME/KSME 2015 Joint Fluids Engineering Conference. American Society of Mechanical Engineers, 2015. http://dx.doi.org/10.1115/ajkfluids2015-3044.
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Storm surge flood is a major threat to the inhabitants of Southwest Louisiana and to the health of the marshes in the area. Knowledge of potential impacts from a flood allows expedited response and recovery. In order to predict the flooding coverage and damage to the wetlands, hydrodynamic simulation of the flooding event has to be conducted. The target model area is Calcasieu Lake and its surrounding wetlands. The wetlands around Calcasieu Lake are covered by marsh grasses. The presence of these marsh grasses have significant effects on the friction of the flooding water, the size of the total flooded area, the speed, and the distribution of the flooding water. In this study, measured grass information was utilized and incorporated into the hydrodynamic model. A comparison between with and without vegetation models was conducted and the effect of the grasses in the target area was revealed.
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Goodwin, M. A., A. F. Shinn, and S. P. Vanka. "Numerical Study of Thermophoretic Deposition in Laminar and Turbulent Variable-Property Flat Plate Channel Flow." In ASME 2009 Heat Transfer Summer Conference collocated with the InterPACK09 and 3rd Energy Sustainability Conferences. ASMEDC, 2009. http://dx.doi.org/10.1115/ht2009-88369.
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Thermophoresis is a significant deposition mechanism for the fouling of exhaust gas recirculation (EGR) coolers. The present paper is motivated by the need to understand and predict the rates of deposition of soot particles in heat exchanger fins used in EGR coolers. This preliminary study considers flat plate channels in the laminar and transitional turbulent regimes. Because of the nano-meter range of the particles, an Eulerian approach is used to determine the particle concentration. Full consideration is given to property variations due to changes in temperature. The inlet gas is at a fixed temperature and the effects of wall temperature are studied for several Reynolds numbers in laminar and transitional turbulent regimes. A finite difference method is used to march downstream in both laminar and transitional turbulent flows. The Launder-Sharma two-equation low-Reynolds-number k-ε model is employed in the numerical simulations to obtain data about flow friction, heat transfer and mass transfer.
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Corral, Roque, and Juan Manuel Gallardo. "Verification of the Vibration Amplitude Prediction of Self-Excited LPT Rotor Blades Using a Fully Coupled Time-Domain Non-Linear Method and Experimental Data." In ASME Turbo Expo 2008: Power for Land, Sea, and Air. ASMEDC, 2008. http://dx.doi.org/10.1115/gt2008-51416.
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The vibration level of aerodynamically unstable low-pressure-turbine rotor blades has been assessed for the first time using two-different approaches. Both methods assume that the aerodynamic forcing is due solely to the self-excitation of the airfoil and that the vibration amplitude is saturated due to the non-linearity associated to the fir-tree dry friction, which is modeled using a simplified approach. To compensate for the limitations of the friction model several hypotheses need to be done, among them, the geometric similarity of the different configurations and that the aspect ratio of the rotor blades is high. The first approach, which is novel, assumes that the vibration amplitude is small enough and the unsteady aerodynamics associated to the airfoil motion may be computed using a frequency domain linearized Navier-Stokes solver. The vibration amplitude is obtained posing the energy balance between the energy exerted by the most unstable aerodynamic mode and the energy dissipated by dry friction. The second approach time marches simultaneously the Reynolds-Average Navier Stokes equations and a simple mass-spring non-linear model consistent with the mechanical model used in the first approach. This fully coupled non-linear, both in the aerodynamic and structural sides, flutter analysis is considered unique in its kind. It is demonstrated by means of a simplified, but consistent with typical low-pressure-turbine bladed-disk, model that both methods are equivalent. The first approach has been applied to several bladed-disks and the comparison with experimental data is good in overall.
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Tijsseling, A. S. "Exact Solution of the Linear Hyperbolic Four-Equation System in Axial Liquid-Pipe Vibration." In ASME 2002 International Mechanical Engineering Congress and Exposition. ASMEDC, 2002. http://dx.doi.org/10.1115/imece2002-32209.
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The so-called “FSI four-equation model” describes the axial vibration of liquid-filled pipes. Two equations for the liquid are coupled to two equations for the pipe, through terms proportional to the Poisson contraction ratio, and through mutual boundary conditions. Skalak (1955/1956ab) defined this basic model, which disregards friction and damping effects. The four equations can be solved with the method of characteristics (MOC). The standard approach is to cover the distance-time plane with equidistantly spaced grid-points and to time-march from a given initial state. This approach introduces error, because either numerical interpolations or wave speed adjustments are necessary. This paper presents a method of exact calculation in terms of a simple recursion. The method is valid for transient events only, because the calculation time grows exponentially with the duration of the event. The calculation time is proportional to the temporal and spatial resolution. The exact solutions are used to investigate the error due to numerical interpolations and wave speed adjustments, with emphasis on the latter.
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Zolfagharroshan, Mohammad, Minghan Xu, Ahmad Zueter, and Agus Sasmito. "Theoretical Study of Counter-Current Liquid-Vapor Flow Under Condensation Conditions Over Non-Isothermal Vertical Wall of Two-Phase Closed Thermosyphon." In ASME 2023 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2023. http://dx.doi.org/10.1115/imece2023-112692.
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Abstract This paper proposes a new mathematical formulation describing the relationship between shear stress and film thickness to model condensing falling film of liquid in vertical thermosyphons. The mathematical model incorporates various factors, encompassing the contribution of shear stress resulting from friction force and phase change at the liquid-vapor interface, the impact of subcooling, and the influence of the convective boundary on film heat transfer. Vapor phase condensation in thermosyphons with relatively longer condenser lengths, where temperature variation is inevitable, is an area of interest for using the proposed model. The novel formulation is solved iteratively with the analytical solution of conservation equations, thermal equilibrium, and thermal resistance analogy. Optimized relaxation factors are used, and when the convergence criteria are met, the model marches over the condenser wall. The high accuracy of the model in regenerating literature data allowed the implementation of parametric study analyses on the variation of ambient air temperature, heat transfer coefficient, and wind velocity. The results are verified with a numerical model based on the modified Nusselt theory, and the underestimation of the latter approach in film thickness prediction and, consequently, heat flux has been discussed. The introduced model indicated the promising potential for laminar to wavy-laminar film regimes and could be applied to similar cases, such as co-current flows and evaporating thin films by minor revision.
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Yu-sheng, Liu, Xu Chao, Zhuang Shao-xin, Li Cong-xin, and Zhang Pan. "Scaling Analysis of Passive Heat Exchanger Under Station Blackout Accident." In 2017 25th International Conference on Nuclear Engineering. American Society of Mechanical Engineers, 2017. http://dx.doi.org/10.1115/icone25-66274.
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Station blackout accidents increasingly become the focus of research in the field of nuclear safety after Japan’s Fukushima nuclear plant accident in March 2011. Core decay heat under station blackout condition will be transferred by natural circulation occurring between core and passive heat exchanger for the nuclear plants incorporated passive safety design concept such as AP1000 or CAP1400. As a result, response of safety systems will differ in accident sequence and kind between passive safety plant and traditional plant. What is more, cooling capacity of passive heat exchanger (PHX) which takes on heat sink has significant effect on performance of natural circulation in passive safety system. The safety need that characteristics of passive safety plant should be verified through integral experiment facility makes scaling analysis important in design or modification of experiment facility. Furthermore, scaling analysis of natural circulation phenomena under station blackout accident plays an important role in design verification, safety review verification or thermo-hydraulic program development. It not only determines the similar similarity criteria between the nuclear power plant prototype and test facility, but also provides technical basis for selecting different experiment schemes. As a part of scaling analysis on natural circulation phenomena for station blackout, the cooling capacity of PHX in test facility should be scaled properly and reasonably with conservatism. Therefore, scaling of passive residual heat removal (PRHR) heat exchanger under station blackout accident is investigated analytically in this paper. The analytical model for natural circulation in passive heat exchanger is established based on the performance characteristics of PRHR system in passive plant. By proper hypothesis and simplification, the governing equations for PHX are normalized using steady-state solutions, initial or boundary conditions. The similarity criteria that should be preserved between PHXs in test facility and prototype are finally obtained from non-dimensionalized equations. Furthermore, the distortion analysis for PHE design is also investigated based on the similarity criteria for selected scaling factors and parameters. The safety analysis based on models of nuclear power plant prototype and test facility is conducted on transient performance of designed PHX with PHX of prototype. The results show that: heat source number is the dominant similarity criteria for PHXs design under SBO condition. Requirements of Richardson number and friction number could be satisfied by resistance adjusting on test loop. The performance of PHX designed following heat source number requirement can better represent the transient response characteristics of prototype under SBO condition.
Reports on the topic "Frictions de marché"
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Obot, N. T., E. B. Esen, and L. Das. Experimental studies of friction and heat transfer in enhanced passages. Progress report, October 1, 1991--March 31, 1992. Office of Scientific and Technical Information (OSTI), March 1992. http://dx.doi.org/10.2172/10135543.
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