A scheme for efficient quantum computation wtih linear optics

Quantum computers promise to increase greatly the efficiency of solving problems such as factoring large integers, combinatorial optimization and quantum physics simulation. One of the greatest challenges now is to implement the basic quantum-computational elements in a physical system and to demonstrate that they can be reliably and scalably controlled. One of the earliest proposals for quantum computation is based on implementing a quantum bit with two optical modes containing one photon. The proposal is appealing because of the ease with which photon interference can be observed. Until now, it suffered from the requirement for non-linear couplings between optical modes containing few photons. Here we show that efficient quantum computation is possible using only beam splitters, phase shifters, single photon sources and photo-detectors. Our methods exploit feedback from photo-detectors and are robust against errors from photon loss and detector inefficiency. The basic elements are accessible to experimental investigation with current technology.

A power system control scheme based on security visualisation in parameter space

Power system real time security assessment is one of the fundamental modules of the electricity markets. Typically, when a contingency occurs, it is required that security assessment and enhancement module shall be ready for action within about 20 minutes’ time to meet the real time requirement. The recent California black out again highlighted the importance of system security. This paper proposed an approach for power system security assessment and enhancement based on the information provided from the pre-defined system parameter space. The proposed scheme opens up an efficient way for real time security assessment and enhancement in a competitive electricity market for single contingency case

Barriers to equality: men's and women's attitudes to workplace entitlements in Australia

This paper examines attitudes to workplace entitlements, such as parental leave and flexible work hours. Family friendly policies such as leave to care for children have implications for feminist debates about sameness versus difference and the extent to which such policies will lead to greater equality between men and women, or alternatively, further entrench existing gender divisions of labour: Using data from a recent national survey in Australia, the paper shows that while the Australian workforce is generally in favour of workplace entitlements, women are generally more supportive of these kinds of benefits than men. Surprisingly, most respondents are more supportive of unpaid rather than paid parental leave. The results also show that the most important determinants of support for work entitlements are a combination of the extent to which one needs work entitlements and employment location. The results raise issues about whether the provision of workplace entitlements will encourage greater participation by men in domestic responsibilities, or simply ease women's double burden of paid and unpaid work.

A director theory for visco-elastic folding instabilities in multilayered rock

A model for finely layered visco-elastic rock proposed by us in previous papers is revisited and generalized to include couple stresses. We begin with an outline of the governing equations for the standard continuum case and apply a computational simulation scheme suitable for problems involving very large deformations. We then consider buckling instabilities in a finite, rectangular domain. Embedded within this domain, parallel to the longer dimension we consider a stiff, layered beam under compression. We analyse folding up to 40% shortening. The standard continuum solution becomes unstable for extreme values of the shear/normal viscosity ratio. The instability is a consequence of the neglect of the bending stiffness/viscosity in the standard continuum model. We suggest considering these effects within the framework of a couple stress theory. Couple stress theories involve second order spatial derivatives of the velocities/displacements in the virtual work principle. To avoid C-1 continuity in the finite element formulation we introduce the spin of the cross sections of the individual layers as an independent variable and enforce equality to the spin of the unit normal vector to the layers (-the director of the layer system-) by means of a penalty method. We illustrate the convergence of the penalty method by means of numerical solutions of simple shears of an infinite layer for increasing values of the penalty parameter. For the shear problem we present solutions assuming that the internal layering is oriented orthogonal to the surfaces of the shear layer initially. For high values of the ratio of the normal-to the shear viscosity the deformation concentrates in thin bands around to the layer surfaces. The effect of couple stresses on the evolution of folds in layered structures is also investigated. (C) 2002 Elsevier Science Ltd. All rights reserved.

Fast-convergent iterative scheme for filtering velocity signals and finding Kolmogorov scales

The present fundamental knowledge of fluid turbulence has been established primarily from hot- and cold-wire measurements. Unfortunately, however, these measurements necessarily suffer from contamination by noise since no certain method has previously been available to optimally filter noise from the measured signals. This limitation has impeded our progress of understanding turbulence profoundly. We address this limitation by presenting a simple, fast-convergent iterative scheme to digitally filter signals optimally and find Kolmogorov scales definitely. The great efficacy of the scheme is demonstrated by its application to the instantaneous velocity measured in a turbulent jet.

Gender equality and participation in housework: A cross-national perspective

This paper examines men's and women's participation in housework in the United States, Sweden, Norway, Canada and Australia. While there has been considerable research into the factors relating to the division of housework between husbands and wives within countries, very little research has examined the way in which housework patterns vary across countries. The results show that women continue to undertake the bulk of domestic labor in all five countries, and that the factors determining men's and women's participation in housework do not vary markedly across countries. This suggests that variations across countries in levels of gender equality at a broader level have only very limited effects on levels of gender equality in the home.

Willingness of Sri Lankan farmers to pay for a scheme to conserve elephants: An empirical analysis

This paper explores the feasibility of adopting an integrated economic approach to raise farmers’ tolerance of the presence of elephants on their farming lands. Responses to this approach were sought from a sample of farmers in the areas affected by human elephant conflict in the northwestern province of Sri Lanka. Results from a contingent valuation survey of their willingness to pay for a scheme to conserve elephants are also reported. Two separate logit regression analyses were undertaken to examine the factors that influence the farmers’ responses for the payment principle question and their opinions on the integrated economic approach. Although found that the majority of the respondents expressed their willingness to pay for the proposed scheme and supported for the implementation of the integrated approach, we have insufficient data yet to determine if their support and financial contribution would be sufficient to set up this programme and also to predict its economic viability. Nevertheless, the overall finding of this study provides an improved economic assessment of the farmers’ attitudes towards the wild elephant in Sri Lanka. At the same time the study shows that, contrary to commonly held assumptions, farmers in this developing country, do support wildlife conservation.

Elucidation of reaction scheme describing malondialdehyde-acetaldehyde-protein adduct formation

Malondialdehyde and acetaldehyde react together with proteins and form hybrid protein conjugates designated as MAA adducts, which have been detected in livers of ethanol-fed animals. Our previous studies have shown that MAA adducts are comprised of two distinct products. One adduct is composed of two molecules of malondialdehyde and one molecule of acetaldehyde and was identified as the 4-methpl-1,4-dihydropyridine-3,5-dicarbaldehyde derivative of an amino group (MHHDC adduct). The other adduct is a 1:1 adduct of malondialdehyde and acetaldehyde and was identified as the 2-formyl-3-(alkylamino)butanal derivative of an amino group (FAAB adduct). In this study, information on the mechanism of MAA adduct formation was obtained, focusing on whether the FAAB adduct serves as a precursor for the MDHDC adduct. Upon the basis of chemical analysis and NMR spectroscopy, two initial reaction steps appear to be a prerequisite for MDHDC formation. One step involves the reaction of one molecule of malondialdehyde and one of acetaldehyde with an amino group of a protein to form the FAAB product, while the other step involves the generation of a malondialdehyde-enamine. It appears that generation of the MDHDC adduct requires the FAAB moiety to be transferred to the nitrogen of the MDA-enamine. For efficient reaction of FAAB with the enamine to take place, additional experiments indicated that these two intermediates likely must be in positions on the protein of close proximity to each other. Further studies showed that the incubation of liver proteins from ethanol-fed rats with MDA resulted in a marked generation of MDHDC adducts, indicating the presence of a pool of FAAB adducts in the liver of ethanol-fed animals. Overall, these findings show that MDHDC-protein adduct formation occurs via the reaction of the FAAB moiety with a malondialdehyde-enamine, and further suggest that a similar mechanism may be operative in vivo in the liver during prolonged ethanol consumption.

Confucianism and the idea of equality

It is often supposed that Confucianism is opposed to the idea of equality insofar as the key ideals to which it is committed, such as meritocracy and li , are incompatible with equality. Sympathetic commentators typically defend Confucianism by saying that (a) the Confucian person is not a free-standing individual but a social being embedded in a social structure with different and unequal roles, and (b) social inequality has to be traded in for other values. This paper argues that in advocating meritocracy, Confucianism does not abandon the idea of equality. Indeed, invoking Aristotle's account of equality in the Nicomachean Ethics , it can be argued that the unequal distribution of rights and benefits reflects one aspect of equality, namely the vertical aspect, or the unequal treatment of unequals.

Estimating economic relationships subject to firm- and time-varying equality and inequality constraints

Applied econometricians often fail to impose economic regularity constraints in the exact form economic theory prescribes. We show how the Singular Value Decomposition (SVD) Theorem and Markov Chain Monte Carlo (MCMC) methods can be used to rigorously impose time- and firm-varying equality and inequality constraints. To illustrate the technique we estimate a system of translog input demand functions subject to all the constraints implied by economic theory, including observation-varying symmetry and concavity constraints. Results are presented in the form of characteristics of the estimated posterior distributions of functions of the parameters. Copyright (C) 2001 John Wiley Sons, Ltd.