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32.
In recent decades, rapid population ageing has dramatically increased the need for older adult care provision in the UK. A prominent role in meeting the care needs of the older population has been played by migrant workers. The aim of this paper is to explore the characteristics of the UK social care system that shape demand for migrant labour, the conditions under which migrant care workers are employed, and older people’s and migrant care workers’ experiences of the quality of care. Our analysis draws on the findings of a survey of providers of social care for older people, in-depth interviews with migrant care workers, and focus groups with older people. The findings show that the underfunding of social care and interrelated workforce shortages are largely responsible for the extensive reliance on migrant workers among social care providers, and raise concerns for workforce inequalities and for the quality of care. 相似文献
33.
A Fabry-Perot resonator filled with second-order nonlinear optical material is investigated. Attention is devoted to making the resonator act as a nonlinear mirror for ultralow-intensity light signals that can be switched by a control beam at the second-harmonic frequency. The interaction process is an input-phase-independent parametric downconversion. The theoretical problem is solved through implementation of a dummy variable method optimized for a parametric process. Efficient amplification and bistability of low-intensity signals have been found. 相似文献
34.
Full first-order linear logic can be presented as an abstract logic programming language in Miller's system Forum, which yields a sensible operational interpretation in the ‘proof search as computation’ paradigm. However, Forum still has to deal with syntactic details that would normally be ignored by a reasonable operational semantics. In this respect, Forum improves on Gentzen systems for linear logic by restricting the language and the form of inference rules. We further improve on Forum by restricting the class of formulae allowed, in a system we call G-Forum, which is still equivalent to full first-order linear logic. The only formulae allowed in G-Forum have the same shape as Forum sequents: the restriction does not diminish expressiveness and makes G-Forum amenable to proof theoretic analysis. G-Forum consists of two (big) inference rules, for which we show a cut elimination procedure. This does not need to appeal to finer detail in formulae and sequents than is provided by G-Forum, thus successfully testing the internal symmetries of our system. 相似文献
35.
36.
A. DAlessio P.L. De Angelis A. Murli M.A. Pirozzi 《Mathematics and computers in simulation》1983,25(5):436-451
Two numerical hydrodynamic models of wind-driven water circulation in a basin are considered.Some results from their application to the Gulf of Naples are described. 相似文献
37.
Elisa Barney Smith David Monn Harsha Veeramachaneni Koichi Kise Alessio Malizia Leon Todoran Adnan El-Nasan Rolf Ingold 《International Journal on Document Analysis and Recognition》2003,6(3):200-206
This document is a collection of four working group reports in the areas of digital libraries, document image retrieval, layout analysis, and Web document analysis. These reports were the outcome of discussions by participants at the Fifth IAPR International Workshop on Document Analysis Systems held in Princeton, NJ on 19-21 August 2002.Published online: 16 March 2004 相似文献
38.
Alessio Gagliardi Thomas A. Niehaus Thomas Frauenheim Alessandro Pecchia Aldo Di Carlo 《Journal of Computational Electronics》2007,6(1-3):345-348
In this paper we present calculations of ballistic transport in molecular wires. The calculations are performed using an approximated
version of the GW correction in the plasmon-pole framework, which is used to improve the starting Density Functional Theory energy spectrum
of the molecule between metallic leads. We show that this correction reduces the error of the correlation part for the electron
energy. Finally a model with complex bands is implemented in order to get the damping regime for long polymers. 相似文献
39.
We propose a method for sparse and robust principal component analysis. The methodology is structured in two steps: first, a robust estimate of the covariance matrix is obtained, then this estimate is plugged-in into an elastic-net regression which enforces sparseness. Our approach provides an intuitive, general and flexible extension of sparse principal component analysis to the robust setting. We also show how to implement the algorithm when the dimensionality exceeds the number of observations by adapting the approach to the use of robust loadings from ROBPCA. The proposed technique is seen to compare well for simulated and real datasets. 相似文献
40.
Liberato Ferrara Alessio Caverzan Lior Nahum Alva Peled 《Materials and Structures》2016,49(5):1747-1760
In this work a granular cementitious composite has been developed, tailoring its performance to a low compressive strength and high deformation and energy dissipation capacity, which can be required to the material when employed in post-installed screeds for protection of structures and infrastructures against accidental actions such as impact and blast. The required level of performance can be achieved by uniform grain size distribution, paste content as low as minimum theoretical void ratio and low paste strength: it is believed that the synergy between the aforementioned three requirements can allow for energy dissipation capacity after paste cracking due to both rearrangement of grain meso-structure and, in case, grain crushing. After the mix design concept and optimization of the material composition, illustrated in the first part of this companion paper study, the mechanical performance of the composite under static and impact compressive loadings has been thoroughly characterized, as affected by mix-design variables, such as paste volume fraction, water to cement ratio and aggregate size. The reliability will thus be thoroughly checked, of the employed material concept, and the influence will also be investigated, if any, of specimen shape, size and boundary conditions. 相似文献