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1.
Louise Shaxson 《Philosophical transactions of the Royal Society of London. Series B, Biological sciences》2009,364(1526):2141-2151
How can we strengthen the science–policy interface for plastics, the environment and human health? In a complex policy area with multiple stakeholders, it is important to clarify the nature of the particular plastics-related issue before trying to understand how to reconcile the supply and demand for evidence in policy. This article proposes a simple problem typology to assess the fundamental characteristics of a policy issue and thus identify appropriate processes for science–policy interactions. This is illustrated with two case studies from one UK Government Department, showing how policy and science meet over the environmental problems of plastics waste in the marine environment and on land. A problem-structuring methodology helps us understand why some policy issues can be addressed through relatively linear flows of science from experts to policymakers but why others demand a more reflexive approach to brokering the knowledge between science and policy. Suggestions are given at the end of the article for practical actions that can be taken on both sides. 相似文献
2.
Gabriela Caballero 《Morphology》2006,16(2):273-289
Although a wide array of phonological properties seem to backcopy in reduplication, it is an open question whether reduplicative
templates can backcopy as well. It has been argued that natural languages do not have reduplicative
constructions where the base truncates to match the truncated reduplicant (McCarthy & Prince, 1994; McCarthy & Prince, 1999;
Spaelti, 1997; inter alia). In Guarijio Abbreviated Reduplication (Miller, 1996), however, both copies of the reduplicative
construction truncate, instantiating the pattern that has been claimed not to exist. This paper argues that the Guarijio case
fills this typological gap. Although the data can be given a templatic backcopying analysis, this paper defends a Morphological
Doubling Theory (MDT) analysis using cophonologies (Inkelas & Zoll, 2005). In MDT, Guarijio Abbreviated Reduplication results
from the parallel imposition of a truncating cophonology in each copy of the reduplicative construction. Guarijio Abbreviated
Reduplication is predicted to exist by MDT together with other documented cases of parallel phonological modification in reduplication.
I am grateful to many people for helpful comments and suggestions, including Isabel Barreras Aguilar, Laura Downing, Nicholas
Fleisher, Andrew Garrett, Jason Haugen, Larry Hyman, Yuni Kim, Teresa McFarland, David Mortensen, Mary Paster, Eric Raimy,
and Timothy Thornes as well as the audience of the LSA 2005 Annual Meeting in Oakland. I would like to extend a special thanks
to Alan Yu for his detailed comments and suggestions to latter versions of this paper. I am particularly indebted to Sharon
Inkelas, for her generous advice, feedback, and numerous discussions throughout the development of this paper. I am also grateful
to two anonymous reviewers for their comments and criticisms, and especially to Ingo Plag for his patience and detailed suggestions
as editor. All remaining errors and omissions are mine. This study was made possible by fellowships by CONACYT (Consejo Nacional
de Ciencia y Tecnología, México), the University of California Institute for Mexico and the United States (UCMEXUS) and Fulbright. 相似文献
3.
Sequential medical trials involving paired data 总被引:2,自引:0,他引:2
4.
The formulation, content, and corollaries of the so-called kT problem are considered. The problem points to a paradox in the biological effect of weak low-frequency magnetic fields. The conventional formulation of the problem contains implicit assumptions that prove not fully valid according to the results of analysis. 相似文献
5.
N. Mielenz 《Biometrical journal. Biometrische Zeitschrift》1984,26(1):1-12
In this paper the problem of unistage selection with inequality constraints is formulated. If the predictor and criterion variables are all normally distributed, this problem can be written as a convex programming problem, with a linear objective function and with linear constraints and a quadratic constraint. Using the duality theory, for convex nonlinear programming it is proved, that its dual problem can be transformed into a convex minimization problem with non-negativity conditions. Good computational methods are known for solving this problem. By the help of the dual problem sufficient conditions for a solution of the original primal problem are derived and illustrated by an example of practical interest. 相似文献
6.
A robust method for selection of variables with the greatest discriminatory power is presented in the paper. The method deals with the two groups of data problem. An application of the method to some respiratory disease data and comparisons with classical procedures are given, also. 相似文献
7.
E.R. Vazquez J.H. Pierluissi 《Computer methods in biomechanics and biomedical engineering》2014,17(2):119-127
Acoustic reflectometry is often used for estimating the cross-sectional area of a cylindrical cavity when used in combination with an acoustic pulse. The objective of this research is to sweep a spectral bandwidth from 50 Hz to 10 kHz at steps of 50 Hz, with Gaussian sinusoidal wave packets, and to apply the Ware–Aki algorithm. In practice, not only it is difficult to generate a broad spectral bandwidth, but also robust methods are required to compensate for attenuation in the propagating wave and to eliminate a DC offset component generated in its impulse response. This paper looks at using numerical techniques to compute the impulse response and estimate the cross-sectional area as a function of an increment in the frequency response. Preliminary results show that both simulated and reconstructed cross-sectional areas for an in vitro model of a human upper airway may be estimated with an appropriate resolution, suggesting that this method is suitable for such applications. 相似文献
8.
9.
J. M. VIAÑO M. BURGUERA J. R. FDEZ-GARCÍA 《Computer methods in biomechanics and biomedical engineering》2013,16(4):273-285
Abstract In this article, the more usual mandible fracture areas are located by identifying the highest stress lines using a three-dimensional (tetrahedral) finite element method. By taking into account the temporomandibular contact and the inertia effects, the mathematical model is considered to be a dynamic Signorini's problem, that is, a dynamic variational inequality which is discretized in time following Newmark's method. So, in each time step a stationary variational inequality is solved by a penalty-duality algorithm. Finally, some numerical results obtained by simulating the more usual fractures in the human mandible are presented and compared with clinical experimental information. 相似文献
10.