781 research outputs found
Single-valley high-mobility (110) AlAs quantum wells with anisotropic mass
We studied a doping series of (110)-oriented AlAs quantum wells (QWs) and
observed transport evidence of single anisotropic-mass valley occupancy for the
electrons in a 150 \AA wide QW. Our calculations of strain and quantum
confinement for these samples predict single anisotropic-mass valley occupancy
for well widths greater than 53 \AA. Below this, double-valley occupation
is predicted such that the longitudinal mass axes are collinear. We observed
mobility anisotropy in the electronic transport along the crystallographic
directions in the ratio of 2.8, attributed to the mass anisotropy as well as
anisotropic scattering of the electrons in the X-valley of AlAs
Automatic Restoration of Diacritics for Igbo Language
Igbo is a low-resource African language with orthographic and tonal diacritics, which capture distinctions between words that are important for both meaning and pronunciation, and hence of potential value for a range of language processing tasks. Such diacritics, however, are often largely absent from the electronic texts we might want to process, or assemble into corpora, and so the need arises for effective methods for automatic diacritic restoration for Igbo. In this paper, we experiment using an Igbo bible corpus, which is extensively marked for vowel distinctions, and partially for tonal distinctions, and attempt the task of reinstating these diacritics when they have been deleted. We investigate a number of word-level diacritic restoration methods, based on n-grams, under a closed-world assumption, achieving an accuracy of 98.83 % with our most effective method
Fast and low cost analysis of dioxin and dioxin-like compounds in marine matrices: final report
0info:eu-repo/semantics/publishe
Product design and business model strategies for a circular economy
© 2016 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group. The transition within business from a linear to a circular economy brings with it a range of practical challenges for companies. The following question is addressed: What are the product design and business model strategies for companies that want to move to a circular economy model? This paper develops a framework of strategies to guide designers and business strategists in the move from a linear to a circular economy. Building on Stahel, the terminology of slowing, closing, and narrowing resource loops is introduced. A list of product design strategies, business model strategies, and examples for key decision-makers in businesses is introduced, to facilitate the move to a circular economy. This framework also opens up a future research agenda for the circular economy.Part of this work was supported by ResCoM, which is co-funded by the European Union under EU Seventh Framework Programme (FP7), Grant agreement number: 603843. We would like to thank the ResCoM team for their support and encouraging discussions on the topic of the circular economy
Tunable Conductivity and Conduction Mechanism in a UV light activated electronic conductor
A tunable conductivity has been achieved by controllable substitution of a
novel UV light activated electronic conductor. The transparent conducting oxide
system H-doped Ca12-xMgxAl14O33 (x = 0; 0.1; 0.3; 0.5; 0.8; 1.0) presents a
conductivity that is strongly dependent on the substitution level and
temperature. Four-point dc-conductivity decreases with x from 0.26 S/cm (x = 0)
to 0.106 S/cm (x = 1) at room temperature. At each composition the conductivity
increases (reversibly with temperature) until a decomposition temperature is
reached; above this value, the conductivity drops dramatically due to hydrogen
recombination and loss. The observed conductivity behavior is consistent with
the predictions of our first principles density functional calculations for the
Mg-substituted system with x=0, 1 and 2. The Seebeck coefficient is essentially
composition- and temperature-independent, the later suggesting the existence of
an activated mobility associated with small polaron conduction. The optical gap
measured remains constant near 2.6 eV while transparency increases with the
substitution level, concomitant with a decrease in carrier content.Comment: Submitted for publicatio
Explicit singular viscosity solutions of the Aronsson equation
We establish that when n≥2 and H∈C1(Rn) is a Hamiltonian such that some level set contains a line segment, the Aronsson equation D2u:Hp(Du)⊗Hp(Du)=0 admits explicit entire viscosity solutions. They are superpositions of a linear part plus a Lipschitz continuous singular part which in general is non-C1 and nowhere twice differentiable. In particular, we supplement the C1 regularity result of Wang and Yu (2008) [11] by deducing that strict level convexity is necessary for C1 regularity of solutions. © 2011 Académie des sciences
Serum dioxin and PCB levels among PCB waste processing plant workers
peer reviewedA clinical investigation and a biological monitoring were carried out to evaluate the occupational exposure of workers in contact with pyralen in a PCB-transformer and capacitor decontamination plant in France. The aim of this study was to assess the body burden of polychlorinated dibenzo-p- dioxin (PCDDs), polychlorinated dibenzofurans (PCDFs), dioxin-like (DL) PCBs and marker PCBs for those workers. We examined 8 representative workers (34-44 years old). The subjects of this study worked from 5 years to 19 years at the plant. All workers reported daily multiple contacts with various metal and wood parts of dismantled transformers during working hours. On a yearly basis, the exposed subjects were examined by the occupational health physician for a check-up. Basic parameters such as liver function and lipid statement were performed
Драматичні елементи у фольклорі – традиція та актуальність
The researches of the folklore and ethnographic sources underscore, that the dramatic elements exist in the folk art (songs, fairy tales, small folklore genres, children folklore etc.), in customs and in the other forms of the life of the folk. But it's importaint what I mean by the notion "dramatic elements in the folklore". Namely, existence of the action, plot, culmination and denouement, then the place and time of the development of the action, monologue, dialogue in the action, characters, masks, dresses, text, scenography, scenario, director, audience, puppet-show, i. e. the presence of the performance. In this paper special attention is given to some dramatic acting with multitude of the dramatic elements, which are connected with large quantity of the Cristmas holidays. We also drew parallels between traditional forms and new elements of celebration and results of the actualization of some innovations in society. It is worth to refer the carnivals in Vechani and Strumitsa and also celebrations of the Eve in Skopje
Resistivity of dilute 2D electrons in an undoped GaAs heterostructure
We report resistivity measurements from 0.03 K to 10 K in a dilute high
mobility 2D electron system. Using an undoped GaAs/AlGaAs heterojunction in a
gated field-effect transistor geometry, a wide range of densities, to , are explored. For high
densities, the results are quantitatively shown to be due to scattering by
acoustic phonons and impurities. In an intermediate range of densities, a peak
in the resistivity is observed for temperatures below 1 K. This non-monotonic
resistivity can be understood by considering the known scattering mechanisms of
phonons, bulk and interface ionized impurities. Still lower densities appear
insulating to the lowest temperature measured.Comment: 4 pages, 4 figure
The efficacy of itraconazole against systemic fungal infections in neutropenic patients : a randomised comparative study with amphotericin B
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