4,875 research outputs found
An Econometric Approach To Estimating Support Prices And Measures Of Productivity Change In Public Hospitals
In industry sectors where market prices are unavailable it is common to represent multiple-input multiple-output production technologies using distance functions. Econometric estimation of such functions is complicated by the fact that more than one variable in the function may be endogenous. In such cases, maximum likelihood estimation can lead to biased and inconsistent estimates of the model parameters and associated measures of firm performance. We solve the problem by using linear programming to construct a quantity index. The distance function is then written in the form of a conventional stochastic frontier model where the explanatory variables are unambiguously exogenous. We use this approach to estimate productivity indexes and support (or shadow) prices for a sample of Australian public hospitals. We decompose the productivity index into several measures of environmental change and efficiency change. We find that the productivity effects of improvements in input-oriented technical efficiency have been largely offset by the effects of deteriorations in the production environment over time.
Critically phase-matched Ti:sapphire-laserpumped deep-infrared femtosecond optical parametric oscillator based on CdSiP2
We report a high-repetition-rate femtosecond optical parametric oscillator (OPO) for the deep-infrared (deep-IR) based on type-I critical phase-matching in CdSiP2 (CSP), pumped directly by a Ti:sapphire laser. Using angle-tuning in the CSP crystal, the OPO can be continuously tuned across 7306–8329 nm (1201–1369 cm−1) in the deep-IR. It delivers up to 18 mW of idler average power at 7306 nm and >7 mW beyond 8000 nm at 80.5 MHz repetition rate, with the spectra exhibiting bandwidths of >150 nm across the tuning range. Moreover, the signal is tunable across 1128–1150 nm in the near-infrared, providing up to 35 mW of average power in ∼266 fs pulses at 1150 nm. Both beams exhibit single-peak Gaussian distribution in TEM00 spatial profile. With an equivalent spectral brightness of ∼5.6×1020photons s−1 mm−2 sr−10.1% BW−1, this OPO represents a viable alternative to synchrotron and supercontinuum sources for deep-IR applications in spectroscopy, metrology, and medical diagnostics.Peer ReviewedPostprint (author's final draft
Moving beyond the ‘language problem': developing an understanding of the intersections of health, language and immigration status in interpreter-mediated health encounters
Health systems internationally are dealing with greater diversity in patient populations. However the focus on ‘the language problem’ has meant little attention is paid to diversity within and between migrant populations; and how interpreted consultations are influenced by intersecting migratory, ethnicity and sociodemographic variables. Our analysis of the experiences of patients, health care providers and interpreters in Scotland evidences the need to move beyond language, addressing multiple hidden inequalities in health care access and provision that operate in both clinic and, especially, home-based settings. We call for a practice-evidenced research agenda promoting cultural communication across health care and home settings, acknowledging immigration status as a social determinant of health.
Sur le plan international, des systèmes de santé font face à une diversité croissante dans ses populations de patients. Cependant, l’accent sur ‘le problème de langue’ se traduit dans une manque d’attention à la diversité a l’intérieur même et entre des populations des migrants; et la façon par laquelle des variables migratoire, ethnique et sociodémographique influencent elles-mêmes des consultations interprétées. Notre analyse des expériences des patients, des professionnels fournissant de soins de santé et des interprètes offre des preuves du besoin de dépasser le problème de langue. Et en faisant cela, nous adressons des multiples inégalités, souvent cachées dans des contextes de soins de santé, dans les milieux clinique et domicile. Nous proposons un programme de recherche basé sur la pratique, qui favorise la communication culturelle dans des milieux clinique et domicile, et qui reconnait le statut d’immigration comme un déterminant social de la santé
An Integrated Telemetric Thermocouple Sensor for Process Monitoring of CFRP Milling Operations
AbstractA wireless temperature measurement system was developed and integrated into a cutting tool holder via a thermocouple embedded within the cutting tool. The primary purpose of such an embedded thermal measurement sensor/system is for online process monitoring of machining processes within which thermal damage poses a significant threat both for the environment and productivity alike – as is the case with the machining of carbon fibre reinforced polymer (CFRP) components. A full system calibration was performed on the device. Response times were investigated and thermal errors, in the form of damping and lag, were identified. Experimental temperature results are presented which demonstrate the performance of the integrated wireless telemetry sensor during the edge trimming of CFRP composite materials. Thermocouple positioning relative to heat source effect was among the statistical factors investigated during machining experiments. Initial results into the thermal response of the sensor were obtained and a statistical package was used to determine the presence of significant main effects and interactions between a number of tested factors. The potential application of the embedded wireless temperature measurement sensor for online process monitoring in CFRP machining is demonstrated and recommendations are made for future advancements in such sensor technology
Quantum matchgate computations and linear threshold gates
The theory of matchgates is of interest in various areas in physics and
computer science. Matchgates occur in e.g. the study of fermions and spin
chains, in the theory of holographic algorithms and in several recent works in
quantum computation. In this paper we completely characterize the class of
boolean functions computable by unitary two-qubit matchgate circuits with some
probability of success. We show that this class precisely coincides with that
of the linear threshold gates. The latter is a fundamental family which appears
in several fields, such as the study of neural networks. Using the above
characterization, we further show that the power of matchgate circuits is
surprisingly trivial in those cases where the computation is to succeed with
high probability. In particular, the only functions that are
matchgate-computable with success probability greater than 3/4 are functions
depending on only a single bit of the input
Optical energies of AllnN epilayers
Optical energy gaps are measured for high-quality Al1−xInxN-on-GaN epilayers with a range of compositions around the lattice match point using photoluminescence and photoluminescence excitation spectroscopy. These data are combined with structural data to determine the compositional dependence of emission and absorption energies. The trend indicates a very large bowing parameter of 6 eV and differences with earlier reports are discussed. Very large Stokes' shifts of 0.4-0.8 eV are observed in the composition range 0.13<x<0.24, increasing approximately linearly with InN fraction despite the change of sign of the piezoelectric fiel
An exact quantification of backreaction in relativistic cosmology
An important open question in cosmology is the degree to which the
Friedmann-Lemaitre-Robertson-Walker (FLRW) solutions of Einstein's equations
are able to model the large-scale behaviour of the locally inhomogeneous
observable universe. We investigate this problem by considering a range of
exact n-body solutions of Einstein's constraint equations. These solutions
contain discrete masses, and so allow arbitrarily large density contrasts to be
modelled. We restrict our study to regularly arranged distributions of masses
in topological 3-spheres. This has the benefit of allowing straightforward
comparisons to be made with FLRW solutions, as both spacetimes admit a discrete
group of symmetries. It also provides a time-symmetric hypersurface at the
moment of maximum expansion that allows the constraint equations to be solved
exactly. We find that when all the mass in the universe is condensed into a
small number of objects (<10) then the amount of backreaction in dust models
can be large, with O(1) deviations from the predictions of the corresponding
FLRW solutions. When the number of masses is large (>100), however, then our
measures of backreaction become small (<1%). This result does not rely on any
averaging procedures, which are notoriously hard to define uniquely in general
relativity, and so provides (to the best of our knowledge) the first exact and
unambiguous demonstration of backreaction in general relativistic cosmological
modelling. Discrete models such as these can therefore be used as laboratories
to test ideas about backreaction that could be applied in more complicated and
realistic settings.Comment: 13 pages, 9 figures. Corrections made to Tables IV and
Distributed Drug Discovery, Part 2: Global Rehearsal of Alkylating Agents for the Synthesis of Resin-Bound Unnatural Amino Acids and Virtual D3 Catalog Construction
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