1,787 research outputs found
GEOGRAPHIC DISTANCE AND R&D ACTIVITIES OF SUBSIDIARIES LOCATED IN SPAIN
This study investigates the impact of geographic distance between the home country of a Multinational Enterprise (MNE) and host countries where subsidiaries are located on the MNEâs decision to carry out overseas research and development (R&D) activities in the host market. The analysis is based on a sample of 1,161 foreign affiliates taken from the PITEC database (Techno-logical Innovation panel), based on the 2005 survey of firmsâ technological innovation activities compiled by the Spanish Statistical Institute (INE). Data allow to distinguish between internal and external R&D activities of firms. I find that, in the sample of Spanish subsidiaries of foreign MNEs, geographic distance negatively affects the likelihood of affiliates sourcing external R&D, but not that of carrying out internal R&D. Furthermore, the results also show that, conditional on doing external R&D, the greater the distance between the source and the host countries, the lower the probability of subsidiaries procuring R&D from local sources in the host country. RĂ©sumĂ© - Cette Ă©tude examine lâimpact de la distance gĂ©ographique entre le pays dâorigine des firmes multinationales et le pays oĂč sont situĂ©es leurs filiales sur leur dĂ©cision dâentreprendre des activitĂ©s de Recherche et DĂ©veloppement (R&D). Lâanalyse utilise un Ă©chantillon de 1161 filiales Ă©trangĂšres installĂ©es en Espagne collectĂ©es Ă partir de la base de donnĂ©es PITEC (Panel dâInnovation Technologique), fondĂ©e sur le questionnaire de lâannĂ©e 2005 sur lâactivitĂ© dâinnovation technologique des firmes de lâInstitut Espagnol de Statistiques (INE). Les donnĂ©es permettent de distinguer entre les activitĂ©s de R&D internes et externes des filiales. Les rĂ©sultats dâun modĂšle biprobit montrent que pour les filiales Ă©trangĂšres en Espagne, la distance a un impact nĂ©gatif sur la proba-bilitĂ© de recourir Ă la R&D externe. Toutefois, la distance nâa pas dâeffet statis-tiquement significatif sur la probabilitĂ© de faire de la R&D pour les filiales des firmes Ă©trangĂšres. Par ailleurs, les rĂ©sultats montrent que plus la distance entre les entreprises-mĂšres et les filiales situĂ©es en Espagne est grande, moins celles-ci sont susceptibles dâacquĂ©rir la technologie de source locale.GEOGRAPHIC DISTANCE, EXTERNAL R&D, INTERNAL R&D, MULTINATIONAL ENTERPRISES
Adhesion energy of single wall carbon nanotube loops on various substrates
The physics of adhesion of one-dimensional nano structures such as nanotubes,
nano wires, and biopolymers on different material substrates is of great
interest for the study of biological adhesion and the development of nano
electronics and nano mechanics. In this paper, we present force spectroscopy
experiments of a single wall carbon nanotube loop using our home-made
interferometric atomic force microscope. Characteristic force plateaux during
the peeling process allows us to access to quantitative values of the adhesion
energy per unit length on various substrates: graphite, mica, platinum, gold
and silicon. By combining a time-frequency analysis of the deflexion of the
cantilever, we access to the dynamic stiffness of the contact, providing more
information on the nanotube configurations and its intrinsic mechanical
properties
Statistical post-processing of hydrological forecasts using Bayesian model averaging
Accurate and reliable probabilistic forecasts of hydrological quantities like
runoff or water level are beneficial to various areas of society. Probabilistic
state-of-the-art hydrological ensemble prediction models are usually driven
with meteorological ensemble forecasts. Hence, biases and dispersion errors of
the meteorological forecasts cascade down to the hydrological predictions and
add to the errors of the hydrological models. The systematic parts of these
errors can be reduced by applying statistical post-processing. For a sound
estimation of predictive uncertainty and an optimal correction of systematic
errors, statistical post-processing methods should be tailored to the
particular forecast variable at hand. Former studies have shown that it can
make sense to treat hydrological quantities as bounded variables. In this
paper, a doubly truncated Bayesian model averaging (BMA) method, which allows
for flexible post-processing of (multi-model) ensemble forecasts of water
level, is introduced. A case study based on water level for a gauge of river
Rhine, reveals a good predictive skill of doubly truncated BMA compared both to
the raw ensemble and the reference ensemble model output statistics approach.Comment: 19 pages, 6 figure
Raman spectra of misoriented bilayer graphene
We compare the main feature of the measured Raman scattering spectra from
single layer graphene with a bilayer in which the two layers are arbitrarily
misoriented. The profiles of the 2D bands are very similar having only one
component, contrary to the four found for commensurate Bernal bilayers. These
results agree with recent theoretical calculations and point to the similarity
of the electronic structures of single layer graphene and misoriented bilayer
graphene. Another new aspect is that the dependance of the 2D frequency on the
laser excitation energy is different in these two latter systems
Fabrication de cellules triple-jonction Ă multi-terminaux
Dans lâindustrie du photovoltaĂŻque Ă concentration, les cellules utilisĂ©es sont des cellules Ă jonctions multiples vu quâelles permettent dâatteindre des efficacitĂ©s Ă©levĂ©es. Celles qui nous intĂ©ressent sont des cellules monolithiques triple-jonction Ă base dâInGaP/ InGaAs/Ge pouvant atteindre un rendement plus que 40 % sous concentration. CommunĂ©ment, on dĂ©pose deux contacts sur la face avant et en dessous de la face arriĂšre qui constituent consĂ©cutivement le contact Ă©metteur et le contact base, dâoĂč lâarchitecture Ă deux terminaux. Dans cette architecture, les sous-cellules sont Ă©lectriquement interconnectĂ©es en sĂ©rie. Si on veut amĂ©liorer les performances de la cellule triple-jonction, il est primordial dâavoir des informations Ă©lectriques sur chaque sous-cellule, dâoĂč la nĂ©cessitĂ© de les caractĂ©riser individuellement. Cependant, avec lâarchitecture Ă deux-terminaux, les caractĂ©risations des sous-cellules ne sont pas Ă©videntes. DâoĂč lâidĂ©e de fabriquer des cellules triple-jonction Ă multi-terminaux telles que les sous-cellules sont Ă©lectriquement indĂ©pendantes, ce qui permet dâavoir un accĂšs direct Ă chacune dâelles et les caractĂ©riser sur une base individuelle. Dans le cadre de cette recherche, un procĂ©dĂ© de gravure chimique sĂ©lective des diffĂ©rentes couches dâempilement Ă base dâInGaP/InGaAs/Ge a Ă©tĂ© dĂ©veloppĂ© en utilisant des solutions chimiques Ă base de H2SO4/H2O2/H2O et HCl/ H3PO4. Ce procĂ©dĂ© a visĂ© Ă rĂ©aliser une architecture permettant, par la suite, le dĂ©pĂŽt des contacts mĂ©talliques Pd/Ge/Ti/Pd/Al, Pt/Ti/Au, Cu/Pt/Ti/Au and Ni/Au sur chacune des sous-cellules en utilisant les techniques de fabrication souvent utilisĂ©es telles que la photolithographie et lâĂ©vaporation. Finalement, des caractĂ©risations en obscuritĂ© des diffĂ©rentes sous-cellules indĂ©pendantes Ă©lectriquement ont Ă©tĂ© effectuĂ©es afin de montrer la fiabilitĂ© du procĂ©dĂ© de fabrication proposĂ©.Abstract : In the concentrated photovoltaic industry, cells often used are multi-junction cells as they can achieve high efficiencies. Cells of interest are monolithic triple-junction cells based on InGaP/InGaAs/Ge that can achieve efficiencies higher than 40% under concentration. Commonly, two contacts are deposited on the front side and underneath the back side which consecutively constitutes the emitter contact and the base contact, hence the two-terminal architecture. In this architecture, the sub-cells are electrically interconnected in series. To improve the performance of the triple-junction cell, it is essential to have electrical information about each sub-cell, hence the need to characterize them individually. However, with the two-terminal architecture, characterizations of sub-cells are not straightforward. Hence, the idea of fabricating multi-terminal triple-junction cells such that sub-cells are electrically independent, allowing direct access to each of them and characterizing them on an individual basis. In this research, a process for wet selective etching of the InGaP/InGaAs/Geâs stack layers was developed using chemical solutions based on H2SO4/H2O2/H2O and HCl/H3PO4. This process aimed to achieve an architecture allowing the subsequent deposition of Pd/Ge/Ti/Pd/Al, Pt/Ti/Au, Cu/Pt/Ti/Au and Ni/Au metal contacts on each of the sub-cells using commonly used fabrication techniques such as photolithography and evaporation. Finally, dark characterisations of different electrically independent sub-cells were carried out to test the reliability of the proposed fabrication process
Gender, globalization and beyond in Karen Tei Yamashita's Tropic of Orange and Jhumpa Lahiri's The Interpreter of Maladies
Ce mĂ©moire explore deux concepts majeurs : la mondialisation et la diaspora et leur impact sur la reprĂ©sentation des femmes dans la sĂ©rie de nouvelles The Interpreter of Maladies de Jhumpa Lahiri et dans le roman Tropic of Orange de Karen Tei Yamashita. Dans le premier chapitre, en sâappuyant sur la thĂ©orie de Vijay Mishra, Literature of the Indian Diaspora: Theorizing the Diasporic Imaginary, ce mĂ©moire examinera lâĂ©tat diasporique de Mrs. Sen Ă travers la notion de « deuil impossible ». Mrs. Sen sera juxtaposĂ©e Ă deux autres personnages fĂ©minins dans le but de dĂ©montrer que la mobilitĂ© et le passage des frontiĂšres nâaffectent pas toutes les femmes de la mĂȘme façon, surtout lorsquâelles viennent de classes et de milieux sociaux diffĂ©rents. De plus, la condition de Mrs. Sen sera Ă©galement comparĂ©e Ă celle de son mari pour soutenir que lâimpact de lâimmigration est plus bĂ©nĂ©fique Ă lui quâĂ elle. Ce mĂ©moire repense donc certaines des raisons qui poussent les gens Ă migrer Ă travers le monde, ainsi quâaux impacts de cette migration sur les individus, en particulier les femmes dont le dĂ©placement limite souvent la mobilitĂ©, la libertĂ© et lâindĂ©pendance. Dans le second chapitre, la thĂ©orie de Chandra Talpade Mohanty, Feminism without Borders, sera utilisĂ©e pour souligner les diffĂ©rences entre la femme occidentale et la femme dite du tiers monde. En outre, lâessai de Mohanty Under Western Eyesâ Revisited, qui condamne les effets nĂ©fastes du capitalisme et de la mondialisation pour promouvoir un projet social basĂ© sur la solidaritĂ©, sera utilisĂ© pour Ă©tudier la description dâEmi et de Rafaela, deux personnages centraux du roman de Yamashita, et ce, dans le contexte de la mondialisation et de ses opĂ©rations dĂ©viantes. Câest en tenant compte des modes opĂ©rationnels criminels et criminisalisant du capitalisme que la mondialisation sera analysĂ©e, et ce, Ă travers la complicitĂ© et la rĂ©sistance des personnages fĂ©minins de Yamashita face au capitalisme global.This thesis explores two major concepts: globalization and diaspora and their impact on the
literary representation of women in Jhumpa Lahiriâs collection of short stories The Interpreter
of Maladies and Karen Tei Yamashitaâs novel Tropic of Orange. In the first chapter, using
Vijay Mishraâs theory on the Literature of the Indian Diaspora: Theorizing the Diasporic
Imaginary, the thesis examines the diasporic state of Mrs. Sen through Mishraâs notion of
âimpossible mourningâ. I juxtapose Mrs. Senâs character to two other female characters to
argue that mobility and crossing borders do not affect all women equally, especially if they
come from different social class and caste backgrounds. In addition, I compare Mrs. Senâs
diasporic condition to her husbandâs to contend that the impact of immigration is more
beneficial to him than her. This thesis, hence, rethinks some of the reasons why people migrate
across the world and its various impacts on individuals, especially women whose displacement
often curtails rather than expands their mobility, freedom and independence. In the second
chapter, therefore, I use Chandra Talpade Mohantyâs Feminism without Borders to highlight
the difference between Western women and so-called Third World women. Furthermore,
using Mohantyâs essay ââUnder Western Eyesâ Revisited,â which condemns the detrimental
effects of capitalism and globalization and promotes an anti-capitalist and anti-global project
based on solidarity, I study the characterization of Emi and Rafaela, two central characters of
Yamashitaâs novel, within the context of globalization and its deviant operations. Referring to
the criminal and criminalizing operative modes of global capitalism, including organ and sex
trafficking, deviant globalization is a critical concept in this thesis through which I read
Yamashitaâs novel and its female charactersâ complicity with and resistance to global
capitalism
Yield stress and elasticity influence on surface tension measurements
We have performed surface tension measurements on carbopol gels of different
concentrations and yield stresses. Our setup, based on the force exerted by a
capillary bridge on two parallel plates, allows to measure an effective surface
tension of the complex fluid and to investigate the influence of flow history.
More precisely the effective surface tension measured after stretching the
bridge is always higher than after compressing it. The difference between the
two values is due to the existence of a yield stress in the fluid. The
experimental observations are successfully reproduced with a simple
elasto-plastic model. The shape of successive stretching-compression cycles can
be described by taking into account the yield stress and the elasticity of the
gel. We show that the surface tension of yield stress fluids is
the mean of the effective surface tension values only if the elastic modulus is
high compared to the yield stress. This work highlights that thermodynamical
quantities measurements are challenged by the fluid out-of-equilibrium state
implied by jamming, even at small scales where the shape of the bridge is
driven by surface energy. Therefore setups allowing deformation in opposite
directions are relevant for measurements on yield stress fluids.Comment: 12 pages, 16 figures in Soft Matter 201
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