130 research outputs found
Economic Uncertainty and European Solidarity: Public Opinion Trends
Impressive growth in public support for the European Community took place during the decade follow ing its founding; there is reason to believe that this development was partly due to the exceptional prosperity then prevailing in the Community's member nations. Con versely, there is evidence that the troubled economic conditions present since expansion of the Community in 1973 have had the opposite effect—subject to some important limiting factors. Analysis of public opinion survey data re veals a positive correlation between support for Community membership and a given nation's level of industrial pro duction at a given time point; and a negative correla tion with rates of inflation. Nevertheless, long-term in fluences seem to dominate the effects of the immediate economic context. Among these long-term factors, length of membership in the Community seems particularly important. But the presence of "Post-Materialist" value priorities, and of relatively high levels of "Cognitive Mobilization" also show significant linkages with public support for European integration.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/68039/2/10.1177_000271627844000108.pd
Carbure de silicium 4H et 3C (microstructures de déformation dans le domaine fragile)
L'objectif de cette thèse est d'étudier le comportement plastique du carbure de silicium dans le domaine fragile. A cette fin, des essais de déformation par micro et nanoindentation ont été réalisés sur des échantillons monocristallins de SiC (4H et 3C). Des couches homoépitaxiées de 4H-SiC de différents dopages électroniques ont été étudiées. Ces couches présentent des caractéristiques mécaniques différentes en fonction du dopage : le dopage de type p durcit le matériau par rapport au dopage de type n ou au matériau intrinsèque. De plus, l'analyse des courbes charge-enfoncement obtenue en nanoindentation montre que la nucléation des dislocations est plus difficile lorsque le matériau est dopé de type p par rapport au matériau dopé n ou intrinsèque. Ceci est confirmé par les microstructures de déformation observées en Microscopie Electronique en Transmission (MET). Les observations par MET montrent que les dislocations introduites à l'ambiante autour des empreintes sont parfaites et glissent dans les plans {0001} dans le 4H-SiC et dans les plans {111} dans le 3C-SiC. Elles sont orientées principalement le long de la direction vis. Les sites de nanoindentation à température ambiante des couches 4H homoepitaxiées ont été particulièrement étudiés. On met en évidence que les sites de nucléation des dislocations sont vraisemblablement situés dans les plans {1100}, les dislocations se développant par la suite dans le plan basal. La nature des cœurs des dislocations parfaites a été déterminée par la technique LACBED. Ces dislocations parfaites ont un cœur silicium en mode shuffle. Un changement de mécanisme de plasticité est observé par MET pour les échantillons indentés 800The aim of this thesis is to study the plastic behaviour of silicon carbide in the brittle domain. For this purpose micro and nanoindentation deformation tests were performed on single crystal specimens of SiC (4H and 3C). Homoepitaxial layers of 4H-SiC with different doping have been studied. These layers show different mechanical characteristics as a function of doping: p-type doping hardens the material as compared to n-type doping or intrinsic material. In addition, load-penetration depthcurves show that the nucleation of dislocations is more difficult in p-doped material as compared to intrinsic or n-doped material. This is confirmed by deformation microstructures observations using Transmission Electron Microscope (TEM). TEM observations show that dislocations introduced around the imprints at room temperature are perfect dislocations gliding in the {0001} plane in 4H-SiC and in the {111} plane in 3C-SiC. They are mostly screw oriented. Room temperature nanoidentation imprints of 4H homoepitaxied layers have been extensively studied. It is evidenced that dislocation nucleation sites are likely to be located in {1100} planes and that dislocations bow out subsequently in the basal plane. The core nature of perfect dislocations has been determined using the LACBED technique. Those perfect dislocations have a silicon core in the shuffle mode. TEM observations on specimens indented at 800 C indicate a change in plastic deformation mechanism. At this temperature, partial dislocations with large stacking faults are observed.POITIERS-SCD-Bib. électronique (861949901) / SudocSudocFranceF
A survey of the combined effects of waterlogging and salinity on fruit yield in the date palm groves of the Wargla basin, Algeria
Introduction. While researchers have paid considerable attention to the effect of soil salinity on crop yield, methodological impediments remain when salinity is combined with other growth factors, especially in farmers' fields. A specific methodology was adapted to assess the effect of waterlogging and salinity on date palm yield ( Phoenix dactylifera L. cv. Deglet Noor). Materials and methods. Date palm yield, water table depth, irrigation water, groundwater and soil salinity were measured in 167 field plots located in five irrigation sectors of the Wargla basin (Algeria). Variance analysis and a boundary line approach were combined to analyze actual and potential yields according to environmental stresses. Results and discussion. High soil salinity resulted from saline irrigation water and a shallow water table. Actual yield decreased with the increase in soil salinity, the decrease in water table depth, and the presence of a gypsum-cemented horizon within the soil profile. The significant effect of the interaction between water table depth and soil salinity showed that the crop responded to the most severe stress rather than to combinations of the individual effects. Potential yield was assessed according to classes of water table depth, soil salinity and the occurrence of a gypsum-cemented horizon. The relationship between soil salinity and potential yield was calibrated according to two models. The limiting factors in order of decreasing importance were shallow water table, high soil salinity and occurrence of a gypsum-cemented horizon for 38.3%, 16.8% and 2.4% of the field plots, respectively; there was no limiting factor for 42.5% of the field plots. In certain sectors, actual yields remained far below potential yields and the additional effect of irrigation water salinity could thus be considered. (Résumé d'auteur
Evaluation of a potential candidate for heavy metal phytostabilization in polluted sites of the Mediterranean littoral (SE Marseille): endomycorrhizal status, fitness biomarkers and metal content of Atriplex halimus spontaneous populations
This study showed that Atriplex halimus forms endomycorrhizae on heavy metal polluted-soils. But no variation of chlorophylls content in leaves was observed. Only low concentrations of heavy metals were found in leaves compared with the high levels of pollutants in the soil. A. halimus appears as a good candidate for phytostabilization of heavy metals in brackish soils
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On the interaction of observation and prior error correlations in data assimilation
The importance of prior error correlations in data assimilation has long been known, however, observation error correlations have typically been neglected. Recent progress has been made in estimating and accounting for observation error correlations, allowing for the optimal use of denser observations. Given this progress, it is now timely to ask how prior and observation error correlations interact and how this affects the value of the observations in the analysis. Addressing this question is essential to understanding the optimal design of future observation networks for high-resolution numerical weather prediction. This paper presents new results which unify and advance upon previous studies on this topic.
The interaction of the prior and observation error correlations is illustrated with a series of 2-variable experiments in which the mapping between the state and observed variables (the observation operator) is allowed to vary. In an optimal system, the reduction in the analysis error variance and spread of information is shown to be greatest when the observation and prior errors have complementary statistics. For example, in the case of direct observations, when the correlations between the observation and prior errors have opposite signs. This can be explained in terms of the relative uncertainty of the observations and prior on different spatial scales. The results from these simple 2-variable experiments are used to inform the optimal observation density for observations of a circular domain (with 32 grid points). It is found that dense observations are most beneficial when they provide a more accurate estimate of the state at smaller scales than the prior estimate. In the case of second order auto-regressive correlation functions, this is achieved when the lengthscales of the observation error correlations are greater than those of the prior estimate and the observations are direct measurements of the state variables
Women Employees in Europe (1984)
Work and occupation situation of women employees in Europe. Topics: type of employment; temporary work; type of job and employer; time worked each week; area of business; company size; position in company hierarchy; company employment; age at start of employment; unemployment experience and length of unemployment; job demands and personal abilities; sex of immediate superior and of colleagues; comparison of occupational situation of women with the situation of male colleagues; assumed equal treatment of men and women in reduction in personnel; personal experiences of sex-specific discrimination in hiring of new employees; judgement on one´s own chances in the job market; job security of spouse; assessment of impact in case of hypothetical unemployment of respondent as well as of spouse (scale); perceived reasons for unemployment of women; attitude to a male privilege in hiring in times of high unemployment; primary earner in the household; personal education; assumed effects of technological development on personal job and type of effects; judgement on personal preparedness as well as ability to adapt to technical changes in comparison to male colleagues; assessment of the possibility of performing the current occupation at home; interest in work at home; influence of high income taxation on interest in a job; knowledge of women not working due to high taxation; experience of sexual harassment at work; knowledge of laws on equal treatment of men and women at work; knowledge of institutions of the European Community and their occupation with problems of equality of men and women at work; judgement on the effectiveness of these departments; judgement on the efforts of trade unions for equal treatment; attitude to trade unions or membership. Demography: marital status; household size; household composition; respondent is head of household; characteristics of head of household; age at leaving school; date of birth; number of children under 8 and between 8 and 15 years in the household.Arbeits- und Berufssituation von weiblichen Beschäftigten in Europa. Themen: Art der Beschäftigung; Zeitarbeit; Art des Arbeitsplatzes und des Arbeitgebers; Wochenarbeitszeit; Branche; Firmengröße; Stellung in der Betriebshierarchie; Betriebszugehörigkeit; Berufseintrittsalter; Arbeitslosigkeitserfahrung und Arbeitslosigkeitsdauer; Arbeitsplatzanforderungen und eigene Fähigkeiten; Geschlecht des unmittelbar Vorgesetzten und der Arbeitskollegen; Vergleich der beruflichen Situation von Frauen mit der Situation der männlichen Kollegen; vermutete Gleichbehandlung von Männern und Frauen bei Personalverringerung; eigene Erfahrungen einer geschlechtsspezifischen Diskriminierung bei der Einstellung neuer Arbeitnehmer; Beurteilung der eigenen Arbeitsmarktchancen; Arbeitsplatzsicherheit des Ehepartners; Einschätzung der Betroffenheit im Falle angenommener Arbeitslosigkeit des Befragten sowie des Ehepartners (Skalometer); perzipierte Gründe für Frauenarbeitslosigkeit; Einstellung zu einem männlichen Vorrecht bei der Einstellung in Zeiten hoher Arbeitslosigkeit; Hauptverdiener im Haushalt; eigene Ausbildung; vermutete Auswirkungen der technologischen Entwicklung auf den eigenen Arbeitsplatz und Art der Effekte; Beurteilung des eigenen Vorbereitetseins sowie Anpassungsfähigkeit an die technischen Veränderungen im Vergleich zu den männlichen Kollegen; Einschätzung der Verrichtungsmöglichkeit der jetzigen Tätigkeit in Heimarbeit; Interesse an Heimarbeit; Einfluß einer hohen Einkommensbesteuerung auf das Interesse an einer Arbeit; Kenntnis von Frauen, die wegen hohen Besteuerung nicht arbeiten; Erfahrung sexueller Belästigungen am Arbeitsplatz; Kenntnis von Gesetzen zur Gleichbehandlung von Männern und Frauen bei der Arbeit; Kenntnis von Einrichtungen der Europäischen Gemeinschaft und deren Beschäftigung mit Problemen der Gleichheit von Mann und Frau am Arbeitsplatz; Beurteilung der Effektivität dieser Abteilungen; Beurteilung der Bemühungen der Gewerkschaften um eine Gleichbehandlung; Einstellung zu den Gewerkschaften bzw. Mitgliedschaft. Demographie: Familienstand; Haushaltsgröße; Haushaltszusammensetzung; Befragter ist Haushaltsvorstand; Charakteristika des Haushaltsvorstands; Schulaustrittsalter; Geburtsdatum; Anzahl der Kinder unter 8 und zwischen 8 und 15 Jahren im Haushalt
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