Labour demand adjustment : Does foreign ownership matter ?

This paper examines whether multinational companies differ in their employment adjustment from domestic firms, on the basis of a panel of Belgian firms for the period 1997-2007. We focus on incumbent firms as, in general, they account for the largest fraction of net employment creation, especially among multinational firms (MNFs). We obtain structural estimates of adjustment cost parameters for blue-collar workers and white-collar workers, domestic firms, and MNFs. We find evidence of convex, asymmetric (in the sense that it is more expensive to downsize than to upsize) and cross adjustment costs (indicating costly substitution between workers). To adjust white-collar employment seems to be around half as costly for MNFs as for domestic firms. There is no difference between Belgian MNFs and foreign MNFs. A small fraction of the gap between the adjustment costs of MNFs and domestic firms may be explained by the use of fixed-term contracts and early retirement. Controlling for firm size does not yield robust conclusions; the cost advantage of MNFs may diminish, vanish or turn into a disadvantage.

The International Strategy of Firms: the Role of Endogenous Product Differentiation

We study the impact of trade liberalization on the international strategy of firms (to export and/or invest abroad as well as the number of products to be produced and exported) when product differentiation is endogenous. By considering product differentiation as a strategic variable, our analysis sheds new light on the impact of trade barriers on the decision to produce abroad and on the choice of product range, in accordance with recent empirical evidence. Indeed, we show that, even though technology exhibits the same productivity for each variety, firms drop some varieties with trade integration. In addition, our results reveal that, contrary to the standard theoretical literature, the relationship between the decision to export and trade costs is non-linear. When trade costs are relatively high, each firm export and is multi-product. Then, when trade costs take intermediate values, firms may invest abroad and the choice of producing abroad results from a prisoner's dilemma game. Finally, when trade costs are low, firms export but become single-product.Foreign direct investment, exports, multi-product competition, endogenous differentiation product, trade integration

Proto-TGO formation in TBC systems fabricated by spark plasma sintering

Thermal barrier coatings (TBC) are commonly used in modern gas turbines for aeronautic and energy production applications. The conventional methods to fabricate such TBCs are EB-PVD or plasma spray deposition. Recently, the spark plasma sintering (SPS) technique was used to prepare new multilayered coatings. In this study, complete thermal barrier systems were fabricated on single crystal Ni-based superalloy (AM1®) substrate in a one-step SPS process. The lifetime of TBC systems is highly dependent on its ability to form during service a dense, continuous, slow-growing alumina layer (TGO) between an underlying bond coating and a ceramic top coat. In the present paper, we show that such kind of layer (called proto-TGO in the following) can be in situ formed during the SPS fabrication of TBC systems. This proto-TGO is continuous, dense and its nature has been determined using TEM-EDS-SAD and Raman spectroscopy. This amorphous oxide layer in the as-fabricated samples transforms to α-Al2O3 during thermal treatment under laboratory air at 1100 °C. Oxidation kinetics during annealing are in good agreement with the formation of a protective α-Al2O3 laye

Portrait des conditions de pratique et de la pénurie des effectifs infirmiers au Québec

This study wants to draw a broad picture of the employment context for nurses in the province of Quebec and to compare it with other provinces. We found that Quebec nurses work less than nurses in the rest of Canada, in terms of effective hours worked, of contracted hours and in terms of overtime worked. That weak work intensity in Quebec could be explained by a larger proportion of part time nurses and by the longer and more frequent sick leaves. We also looked at the shortage of nurses, as computed by the department of Health and social services (Ministère de la Santé et des services sociaux). We found that the so-called shortage of nurses did not represent the needs of workers to give more services to the patients, but the needs of workers to eliminate extra overtime worked by nurses. We also found that methodological choices made by the department lead to an overestimation of 16% to 18% of the effective shortage. Three scenarios of increased work effort show that it would be possible to reduce the shortage by 20% to 30%, including the methodological correction on the computations. Ce document vise à établir un portrait du contexte de pratique des effectifs infirmiers québécois et de les comparer avec celui qui prévaut dans les autres provinces canadiennes. On trouve dans un premier temps que l’intensité de travail des infirmières québécoises est plus faible que celle du reste du Canada, notamment au chapitre des heures effectives travaillées, des heures contractées et des heures supplémentaires. Cette intensité moindre pourrait s’expliquer par une plus grande proportion d’infirmières à temps partiel et par des absences plus longues et plus fréquentes au Québec que dans les autres provinces. On aborde également le calcul de la pénurie d’infirmières effectué par le MSSS. On trouve que ce calcul ne reflète pas les besoins d’effectifs infirmiers pour répondre à la demande pour les soins de santé, mais bien les besoins en effectifs qui permettraient d’éliminer les heures supplémentaires excédentaires travaillées par les infirmières. On trouve également que les choix méthodologiques surestiment de 16 % à 18 % la pénurie effective. Divers scénarios montrent ensuite l’effet d’une augmentation graduelle de l’intensité du travail des infirmières sur l’ampleur de la pénurie. Ceux-ci montrent une diminution de 20 % à 30 % de la pénurie, en incluant la correction méthodologique abordée précédemment.Nurses, nurses’ shortage, health economics, health care., Effectifs infirmiers, pénurie d’infirmières, économie de la santé, soins de santé.

Thermal cycling behavior of EBPVD TBC systems deposited on doped Pt-rich γ–γ′ bond coatings made by Spark Plasma Sintering (SPS)

In the last decade, an increasing interest was given to Pt-rich γ–γ′ alloys and coatings as they have shown good oxidation and corrosion properties. In our previous work, Spark Plasma Sintering (SPS) has been proved to be a fast and efficient tool to fabricate coatings on superalloys including entire thermal barrier coating systems (TBC). In the present study, this technique was used to fabricate doped Pt-rich γ–γ′ bond coatings on AM1® superalloy substrate. The doping elements were reactive elements such as Hf, Y or Zr, Si and metallic additions of Ag. These samples were then coated by electron beam physical vapour deposition (EBPVD) with an yttria partially stabilized zirconia (YPSZ) thermal barrier coating. Such TBC systems with SPS Pt rich γ–γ′ bond coatings were compared to conventional TBC system composed of a β-(Ni,Pt)Al bond coating. Thermal cycling tests were performed during 1000-1 h cycles at 1100 °C under laboratory air. Spalling areas were monitored during this oxidation test. Most of the Pt rich γ–γ′ samples exhibited a better adherence of the ceramic layer than the β-samples. After the whole cyclic oxidation test, cross sections were prepared to characterize the thickness and the composition of the oxide scales by using scanning-electron microscopy. In particular, the influence of the doping elements on the oxide scale formation, the metal/oxide roughness, the TBC adherence and the remaining Al and Pt under the oxide scale were monitored. It was shown that RE-doping did not improve the oxidation kinetics of the studied Pt rich γ–γ′ bond coatings, nevertheless most of the compositions were superior to “classic” β-(Ni,Pt)Al bond coatings in terms of ceramic top coat adherence, due to lower rumpling kinetics and better oxide scale adherence of the γ–γ′-based systems

Lattice stability and formation energies of intrinsic defects in Mg2Si and Mg2Ge via first principles simulations

We report an ab initio study of the semiconducting Mg2X (with X = Si, Ge) compounds and in particular we analyze the formation energy of the different point defects with the aim to understand the intrinsic doping mechanisms. We find that the formation energy of Mg2Ge is 50 % larger than the one of Mg2Si, in agreement with the experimental tendency. From the study of the stability and the electronic properties of the most stable defects taking into account the growth conditions, we show that the main reason for the n-doping in these materials comes from interstitial magnesium defects. Conversely, since other defects acting like acceptors such as Mg vacancies or multivacancies are more stable in Mg2Ge than in Mg2Si, this explains why Mg2Ge can be of n or p type, contrary to Mg2Si. The finding that the most stable defects are different in Mg2Si and Mg2Ge and depend on the growth conditions is important and must be taken into account in the search of the optimal doping to improve the thermoelectric properties of these materials.Comment: 25 pages, 6 Table