805 research outputs found
Local and global minimizers for a variational energy involving a fractional norm
No full textWe study existence, uniqueness, and other geometric properties of the minimizers of the energy functional
∥u∥2Hs(Ω)+∫ΩW(u)dx,
where ∥u∥Hs(Ω) denotes the total contribution from Ω in the H s norm of u and W is a double-well potential. We also deal with the solutions of the related fractional elliptic Allen-Cahn equation on the entire space Rn . The results collected here will also be useful for forthcoming papers, where the second and the third author will study the Γ-convergence and the density estimates for level sets of minimizers
A Soviet cargo for the experiment NA4 landed at Cointrin
No full textSee photo 7802387. Among the crowd, Nicolas Koulberg (third from left) and at his right Igor Golutvin (talking to a journalist ?), Igor Savin (second from right) and at his left Mike Doran
L'arche de Noé de Saint-Savin
No full textThe depiction of the ark at Saint-Savin-sur-Gartempe was noted mainly because of the two giant figures holding onto the roof of the ark. Similar representation can be found in the murals of the church of Saint Jean Baptist de Château-Gontier. The author shows their origin to be in Jewish legends. The distribution of the animals and humans in the ark points also to the same origins. The article compares the depiction of the ark in Saint-Savin with those of the illuminations in the manuscripts of the Caedmon poetry, wich shows angels in a somewhat similar position, with the Aelfric paraphrase, as well as the paintings by W. de Brailes, all of which show some traces of Jewish legends. The unconventional form of the sequence and continuity of the stories depicted in the vault painting in the nave of Saint-Savin and the direction of some of the depictions from right to left may point also to an earlier pictorial model of Jewish origin.La représentation de l'arche de Noé à Saint-Savin-sur-Gartempe et son exceptionnelle iconographie ont retenu l'attention des chercheurs essentiellement focalisés sur les deux personnages gigantesques agrippés à la toiture de l'arche. La même représentation figure à l'église Saint-Jean-Baptiste de Château-Gontier. L'A. en fait remonter l'origine aux légendes juives, origine qu'atteste également la distribution des animaux et des hommes aux différents points de l'arche. L'article compare la représentation de l'arche de Saint-Savin, d'une part avec celle des enluminures des manuscrits du poème de Caedmon, où les anges affectent une position quelque peu semblable, d'autre part avec celle de la paraphrase d'Aelfric et des peintures de W. de Brailes, où l'on relève aussi des traces de légendes juives. La forme non conventionnelle des séquences et le fait que la lecture de certaines images se fasse de droite à gauche renvoient aussi à un modèle pictural précoce d'origine juive.Friedman Mira. L'arche de Noé de Saint-Savin. In: Cahiers de civilisation médiévale, 40e année (n°158), Avril-juin 1997. pp. 123-143
Flat level set regularity of p-Laplace phase transitions
No full textWe prove a Harnack inequality for level sets of p-Laplace phase transition minimizers. In particular, if a level set is included in a flat cylinder, then, in the interior, it is included in a flatter one. The extension of a result conjectured by De Giorgi and recently proven by the third author for p = 2 follows
Elliptic boundary value problems associated with isometric group actions
No full textGiven a manifold with boundary endowed with an action of a discrete group on it, we consider the algebra of operators generated by elements in the Boutet de Monvel algebra of pseudodifferential boundary value problems and shift operators acting on functions on the manifold and its boundary. Provided that the group is of polynomial growth and its action is isometric, we construct a Chern character for elliptic elements in this algebra with values in a de Rham type cohomology of the fixed point manifolds for the group action and obtain an index formula in terms of this Chern character. Our index formula contains as special cases the index formula by Fedosov for boundary value problems in the Boutet de Monvel algebra and the index formula by Nazaikinskii, Savin and Sternin for operators on a closed manifold associated with an isometric group action. © 2021, The Author(s), under exclusive licence to Springer Nature Switzerland AG
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Eu telecommunications law /
No full textEU Telecommunications Law provides a comprehensive overview of the current European regulatory framework as it applies to telecommunications and examines the challenges facing regulators in this sector. Key chapters focus on the selection of appropriate regulatory models that serve to encourage effective investment in next-generation networks and ensure their successful deployment. Andrej Savin provides an up to date overview of all the relevant sources, guiding the reader through these disparate materials in a simple and systematized way. In particular, the book provides analysis of the 2016 proposal for a European Electronic Communications Code (EECC). Using the 2009 Regulatory Framework on electronic communications as a basis the author analyses each of the 2009 framework's five main directives, comparing them with the changes proposed in the EECC. Providing a comprehensive introduction to the main areas of EU telecoms regulation, this book will be of great value to telecoms and IT lawyers. It will also appeal to academics carrying out research in IT law or competition law as it relates to IT and telecoms. EU Telecommunications Law provides a comprehensive overview of the current European regulatory framework as it applies to telecommunications and examines the challenges facing regulators in this sector. Key chapters focus on the selection of appropriate regulatory models that serve to encourage effective investment in next-generation networks and ensure their successful deployment. Andrej Savin provides an up to date overview of all the relevant sources, guiding the reader through these disparate materials in a simple and systematized way. In particular, the book provides analysis of the 2016 proposal for a European Electronic Communications Code (EECC). Using the 2009 Regulatory Framework on electronic communications as a basis the author analyses each of the 2009 framework's five main directives, comparing them with the changes proposed in the EECC. Providing a comprehensive introduction to the main areas of EU telecoms regulation, this book will be of great value to telecoms and IT lawyers. It will also appeal to academics carrying out research in IT law or competition law as it relates to IT and telecoms
A model for simulating the height of rice plants
No full textA reliable approach for modelling rice plant height would allow the simulation of processes with a significant impact on yields, e.g., lodging, floodwater effect on leaves temperature, crop-weeds competition for radiation interception. In this paper we present a new model for the simulation of rice plant height based on the integral of the percentage of biomass partitioned to stems. The model was compared with four alternative approaches using data collected during eight experiments carried out in Russia, Japan and US between 1991 and 2000, proving to be the most accurate in reproducing plant height during the whole crop cycle. RRMSE ranged between 8.02% and 20.87%, modelling efficiency was always close to one and the absolute value of coefficient of residual mass never exceeded 0.16. It resulted also the most robust and the less complex (according to the Akaike's Information Criterion) among those compared. The model presents a lower level of empiricism with respect to the other approaches found in the literature, deriving plant height from the allocation of biomass to stems, which are the plant organs most involved in determining canopy height. This model represents a suitable base for further developments aiming at including the effect of management practices (e.g., fluctuating water depth) and environmental factors (e.g., crop-weeds competition for radiation interception). Moreover, the low input requirements favour its inclusion in operational cropping systems models
Silicon Surface Passivation by Mixed Aluminum Precursors in Al2O3 Atomic Layer Deposition
No full textDimethylaluminum chloride (DMACl) is a cost-effective aluminium precursor alternative to conventional trimethylaluminium (TMA) for Atomic Layer Deposited (ALD) Al2O3. The DMACl water process shows better passivation after high temperature firing when compared with conventional TMA water process. However, after low-temperature post-anneal its passivation quality is slightly worse than with TMA. Here we show that a mixed use of TMA and DMACl precursors in the ALD process results in better surface passivation both after 400 °C post-anneal and after an 800 °C firing step. The high-quality passivation results from the low interface defect density and high negative charge at the surface. Specifically, we investigate the role of chlorine in the ALD Al2O3 passivation by varying the TMA and DMACl pulse proportions.Peer reviewe
4 per 1000 soil carbon sequestration
No full textBudiman Minasny, Alex. B. McBratney, Brendan P. Malone, Denis A. Angers, Dominique Arrouays, Adam Chambers, Vincent Chaplot, Zueng-Sang Chen, Kun Cheng, Bhabani S. Das, Damien J. Field, Alessandro Gimona, Carolyn Hedley, Suk Young Hong, Biswapati Mandal, Ben P. Marchant, Manuel Martin, Brian G. McConkey, Vera Leatitia Mulder, Sharon O’Rourke, Anne C. Richer-de-Forges, Inakwu Odeh, José Padarian, Keith Paustian,Genxing Pan, Laura Poggio, Igor Savin, Vladimir Stolbovoy, Uta Stockmann, Yiyi Sulaeman, Chun-Chih Tsui, Tor-Gunnar Vågen, Bas van Wesemael, Leigh Winowiecki 2017. 4 per 1000 soil carbon sequestration. Proceedings of the Global Symposium on Soil Organic Carbon 2017. 21-23 March 2017. Rome, Italy. FAO.International audienc
Effect of Different ALD Al2O3 Oxidants on the Surface Passivation of Black Silicon
No full textAbstractWe study how different oxidants in atomic layer deposition of aluminium oxide (ALD Al2O3) affect the surface passivation of black silicon. Here we show that processes using ozone cause higher fixed charge but surprisingly lead to lower lifetimes in black silicon samples as compared to water-based samples. In planar samples however, the best surface passivation is reached with O3-based processes. In case of water as oxidant, the planar wafers suffer from severe blistering and poorer surface passivation, while this seems to be the best process for black silicon. To find a reason for the lifetime differences we also study different Al2O3 stacks where both H2O and O3 are used as oxidants. In conclusion, surface texture seems to affect the optimal oxidant in the ALD process
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