458 research outputs found
Domain variance and superstructure across the antiferroelectric/ferroelectric phase boundary in Pb1−1.5xLax(Zr0.9TiM0.1)O3
Transmission electron microscopy, x-ray diffraction, relative permittivity as a
function of temperature, and polarization versus field loops were used to study the
antiferroelectric/ferroelectric (AFE/FE) phase boundary in Pb1−1.5xLaxZr0.9Ti0.1O3
(PLZT, 100x/90/10) ceramics. X-ray diffraction and electrical measurements indicated
a FE rhombohedral (R) to AFE tetragonal (T) phase transition between PLZT 2/90/10
and 4/90/10. Both phases exhibited superstructure reflections in electron-diffraction
patterns at 1⁄2{hkl} positions consistent with rotations of the octahedra in antiphase.
Previously, neutron diffraction suggested that the FER has an a−a−a− tilt system
(Glazer notation), in agreement with its macroscopic symmetry. By analogy, it is
proposed that the AFET phase has an a0a0c− tilt system. The AFE phase was also
characterized by incommensurate superstructure along pseudocubic 〈110〉p directions,
whereas the FE phase had extra commensurate superlattice reflections at 1⁄2{hk0}p
positions. 1⁄2{hk0}p reflections are forbidden in both tilt systems, but their presence is
explained by Pb ion displacements averaged along 〈111〉 but with short coherence
antiparallel components along 〈110〉 directions. The antiparallel Pb displacements are
coupled to an a−b−b− (a ≈ b) monoclinic tilt system in the vicinity of the AFE/FE
boundary
Can biochemical analyses risk stratify acutely admitted medical patients: an external validation of two existing systems
A Dynamic Market Mechanism for Integration of Renewables and Demand Response
The most formidable challenge in assembling a Smart Grid is the integration of a high penetration of renewables. Demand Response, a largely promising concept, is increasingly discussed as a means to cope with the intermittent and uncertain renewables. In this paper, we propose a dynamic market mech- anism that reaches the market equilibrium through continuous negotiations between key market players. In addition to incor- porating renewables, this market mechanism also incorporates a quantitative taxonomy of demand response devices, based on the inherent magnitude, run-time, and integral constraints of demands. The dynamic market mechanism is evaluated on an IEEE 118 Bus system, a high fidelity simulation model of the Midwestern United States power grid. The results show how the proposed mechanism can be utilized to determine combinations of demand response devices in the presence of intermittent and uncertain renewables with varying levels of penetration so as to result in a desired level of Social Welfare.This work was supported in part by the National Science Foundation grants ECCS-1135815 and EFRI-1441301
RIO Country Report 2017: Denmark
The R&I Observatory country report 2017 provides a brief analysis of the R&I system covering the economic context, main actors, funding trends & human resources, policies to address R&I challenges, and R&I in national and regional smart specialisation strategies. Data is from Eurostat, unless otherwise referenced and is correct as at January 2018. Data used from other international sources is also correct to that date. The report provides a state-of-play and analysis of the national level R&I system and its challenges, to support the European Semester.JRC.B.7-Knowledge for Finance, Innovation and Growt
RIO Country Report 2016: Denmark
The 2016 series of the RIO Country Report analyses and assesses the development and performance of the national research and innovation system of the EU-28 Member States and related policies with the aim of monitoring and evaluating the EU policy implementation as well as facilitating policy learning in the Member States.JRC.B.7-Knowledge for Finance, Innovation and Growt
Modelling of a High Temperature PEM Fuel Cell Stack using Electrochemical Impedance Spectroscopy
Hardware Resource Allocation for Hardware/Software Partitioning in the LYCOS System
This paper presents a novel hardware resource alloca-tion technique for hardware/software partitioning. It al-locates hardware resources to the hardware data-path us-ing information such as data-dependencies between op-erations in the application, and profiling information. The algorithm is useful as a designer’s/designtool’s aid to generate good hardware allocations for use in hard-ware/software partitioning. The algorithm has been imple-mented in a tool under the LYCOS system [9]. The results show that the allocations produced by the algorithm come close to the best allocations obtained by exhaustive search.
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