50 research outputs found
Le rôle des caractéristiques sectorielles dans la détermination des performances à l'exportation
No full text[eng] Alain Roncin - Sectoral characteristics and export performances. The analysis of the role of the sectoral characteristics in the explanation of the expert performances must satisfy various requirements, which are seldom satisfied simultaneously in empirical studies. These requirements are concerned first with the way the characteristics of the sectors are taken into account (level of disaggregation, reference to the effective production factor combination in the country concerned, heterogeneity of production factors) and secondly with the necessary recognition of the multiplicity of the explanatory factors involved. The analysis of the export performances of France, Germany and the U.S tends to show that the influence of the variables considered, in particular of the variables considered, in particular of the factor coefficient, in particular of the factor coefficient, is quite diffeentiated according to the country concerned. The results obtained. The results obtained from models applied to subsets of the industrial activity tend to show that it is not possible to explain all trade flows with a unique model. [fre] Alain Roncin - Le role des caractéristiques sectorielles dans la détérmination des performances à l'exportation. La recherche de l'action des caractéristiques sectorielles sur les performances à l'exportation des activités industrielles doit répondre à plusieurs conditions rarement respectées simultanément dans les études empiriques. Les conditions tiennent d'une part au mode de prise en compte des caractéristiques sectorielles (analyse à un niveau désagrégé, caractérisation des activités selon les valeurs effectives des combinaisons productives, hétérogénéité des facteurs) et d'autre part à la reconnaissance de la multiplicité des déterminants du commerce international. L'analyse des performances extérieures de la France, de la R.F.A. et des Etats Unis, met en évidence une action différenciée selon les pays des variables introduites et notamment celle des facteurs de production. Les résultats obtenus à partir des partitions de l'ensemble des activités industrielles, montrent qu' un modèle unique ne peut expliquer l'ensemble des échanges de produits manufacturés.
INTERMOLECULAR POTENTIAL OF EXCITED ATOMS AND MOLECULES FROM MATRIX SHIFTS.
No full text J.-Y. Roncin, J. Mol. Spectry, 26, 105 (1968). J.-Y. Roncin, N. Damany and B. Vodar, Chem. Phys. Letters, March 1969.Author Institution: Laboratoire des Hautes, Pressions, C.N.R.S., Bellevue France and National Research Council of Canada Division of Pure PhysicsThe experimental shifts and broadening of far u.v. transitions of trapped species have so far permitted only qualitative conclusions concerning the dimensions of the excited In particular the matrix isolation technique has strikingly shown the profound difference in behavior of trapped molecules according to the nature of the transition; valence transitions are little affected whereas Rydberg transitions are strongly Enough experimental data are now available to attempt a quantitative estimation of the dimension of some excited states on the basis of a simple Lennard-Jones intermolecular potential . The values of and , computed for some excited states of Xe, Kr, Hg, CO, NO and , are given below: [FIGURE] During the year 1969, J.-Y. Roncin has been a Postdoctoral Fellow at the Division of Pure Physics, National Research Council of Canada, Ottawa, Canada
L'engagement des PMI dans l'exportation
No full textThe Involvement of Small and Medium-sized Firms in Exporting - Theoretical economic analyses give relatively little importance, somewhat surprisingly, to a firm's size as a decisive factor which influences its tendency to export. Furthermore, on an empirical level, the results of studies in this area are at times contradictory. This article attempts to evaluate within French industrial firms to what extent there exists a link between size (mesured as the number of employees) and the tendency to export. Within industry taken as a whole, such a relation does exist, although small and medium-sized firms are not excessively present among low-export industries. From the standpoint of sector, however, the relationship has only a limited value : by using a rigorous procedure of statistical tests, it emerges that, out of 47 individual sectors, the link is significant only within thirteen of them. Nearly all of these sectors belong to the areas of professional capital goods and intermediary goods.Les analyses économiques théoriques accordent assez peu d'importance, contrairement à ce qu'on pourrait penser, à la dimension de l'entreprise comme facteur décisif favorisant la tendance à exporter. Empiriquement, les résultats sont d'ailleurs parfois contradictoires. L'article s'attache à apprécier, sur les entreprises industrielles françaises, l'existence d'une relation entre la taille (mesurée par le nombre de salariés) et la propension à exporter. Dans l'industrie prise globalement, la relation existe, bien que les PMI ne soient que peu sur-représentées parmi les entreprises faiblement exportatrices. Au niveau sectoriel, en revanche, la relation n'a qu'une portée limitée: l'utilisation d'une procédure rigoureuse de tests statistiques indique que, sur les 47 secteurs individualisés, la liaison n'est significative que dans 13. Ces secteurs font presque tous partie des biens d'équipement professionnel et des biens intermédiaires.Obligación para la pequena y mediana empresa de exportar - Los análisis economicos teoricos dan escasa importancia, a la inversa de lo que se pudiere suponer, al tamaño de la empresa como factor decisivo que favorece la propension a exportar. Empiricamente, los resultados se verifican a veces contradictories. El articulo se aplica a estimar, respecto a las empresas industriales francesas, la presencia de una relación entre dimension, medida por el numéro de asalariados y tendencia a exportar. En la industria, considerada globalmente, la relación existe si bien la pequena y mediana industria destaca poco entre empresas escasamente exportadoras. A nivel sectoral, en cambio, la relación es de poco alcance : la utilización de un procedimiento rigoroso de pruebas estadisticas pone de manifiesto que de 47 sectores individual ados, el vinculo no es significativo más que en 13 de ellos. Casi todos estos sectores forman parte de los bienes de equipo profesional y de bienes intermedios.Roncin Alain. L'engagement des PMI dans l'exportation. In: Economie et statistique, n°148, Octobre 1982. Les PME face aux grandes entreprises / France et RFA dans la crise. pp. 39-51
L'engagement des PMI dans l'exportation
No full text[eng] The Involvement of Small and Medium-sized Firms in Exporting - Theoretical economic analyses give relatively little importance, somewhat surprisingly, to a firm's size as a decisive factor which influences its tendency to export. Furthermore, on an empirical level, the results of studies in this area are at times contradictory. This article attempts to evaluate within French industrial firms to what extent there exists a link between size (mesured as the number of employees) and the tendency to export. Within industry taken as a whole, such a relation does exist, although small and medium-sized firms are not excessively present among low-export industries. From the standpoint of sector, however, the relationship has only a limited value : by using a rigorous procedure of statistical tests, it emerges that, out of 47 individual sectors, the link is significant only within thirteen of them. Nearly all of these sectors belong to the areas of professional capital goods and intermediary goods. [spa] Obligación para la pequena y mediana empresa de exportar - Los análisis economicos teoricos dan escasa importancia, a la inversa de lo que se pudiere suponer, al tamaño de la empresa como factor decisivo que favorece la propension a exportar. Empiricamente, los resultados se verifican a veces contradictories. El articulo se aplica a estimar, respecto a las empresas industriales francesas, la presencia de una relación entre dimension, medida por el numéro de asalariados y tendencia a exportar. En la industria, considerada globalmente, la relación existe si bien la pequena y mediana industria destaca poco entre empresas escasamente exportadoras. A nivel sectoral, en cambio, la relación es de poco alcance : la utilización de un procedimiento rigoroso de pruebas estadisticas pone de manifiesto que de 47 sectores individual ados, el vinculo no es significativo más que en 13 de ellos. Casi todos estos sectores forman parte de los bienes de equipo profesional y de bienes intermedios. [fre] Les analyses économiques théoriques accordent assez peu d'importance, contrairement à ce qu'on pourrait penser, à la dimension de l'entreprise comme facteur décisif favorisant la tendance à exporter. Empiriquement, les résultats sont d'ailleurs parfois contradictoires. L'article s'attache à apprécier, sur les entreprises industrielles françaises, l'existence d'une relation entre la taille (mesurée par le nombre de salariés) et la propension à exporter. Dans l'industrie prise globalement, la relation existe, bien que les PMI ne soient que peu sur-représentées parmi les entreprises faiblement exportatrices. Au niveau sectoriel, en revanche, la relation n'a qu'une portée limitée: l'utilisation d'une procédure rigoureuse de tests statistiques indique que, sur les 47 secteurs individualisés, la liaison n'est significative que dans 13. Ces secteurs font presque tous partie des biens d'équipement professionnel et des biens intermédiaires.
Validation of a simple aerodynamic model capable to predict the interaction effects occuring between two generic wind propulsion systems
No full textIn recent years wind-assisted propulsion for commercial ships has gained an increasing interest as valuable alternative to reduce fuel pollutant emissions. However, the development of feasible and commercially viable wind propulsion systems to partially (or fully) propel a ship is nowadays hindered by the difficulties of modelling the complicated aerodynamic and hydrodynamic aspects involved. From an aerodynamic point of view, it appears that one of the main challenges of predicting the performance of a wind-assisted ship, is to properly evaluate the interaction effects that occur between the various wind propulsion systems mounted on the deck of the ship. This research deals with the validation of a simple and quick-to-use aerodynamic model that is capable of evaluating such effects, i.e. upwash, downwash and wake, occurring between two generic propulsion systems placed at any given relative position on the ship's deck. The wind propulsion systems might assume any given angle of attack; the flow can be attached as well as separated. Such aerodynamic model, that was first presented in [1], consists of the horseshoe vortex method modified with semi-empirical formulas to take into account the effects of viscosity. First, the results provided by the aerodynamic model were compared with results obtained by using more sophisticated tools, i.e. a CFD body force model and RANS CFD. Then, experimental validation was carried out by means of dedicated wind-tunnel tests. It can be concluded that, despite the simplicity of the aerodynamic model employed, it proved to give reasonable results when compared to more sophisticated tools and to experimental data. REFERENCES [1] K. Roncin and J.M. Kobus, “Dynamic simulation of two sailing boats in match racing”, Sports Engineering , Vol. 7, pp. 139-152, (2004)
