Peculiar Velocity and Deaberration of the Sky

Recent studies have found the earth's peculiar velocity to be significant in microwave background based tests for compact cosmic topology, and modifications to these tests have been proposed. Tests of non-gaussianity, weak lensing analysis and new tests using improved CMB data will also be sensitive to peculiar velocity. We propose here to simplify matters by showing how to construct a deaberrated CMB map to which any test requiring a Hubble flow viewpoint can be applied without further complication. In a similar manner deaberration can also be applied to object surveys used for example in topological searches and matter distribution analysis. In particular we have produced a revised list of objects with z > 1.0 using the NASA/IPAC Extragalactic Database.Comment: 8 pages, 1 figure, v4 accepted by Ap

The Failure of Uncovered Interest Parity: Is it Near-rationality in the Foreign Exchange Market?

A risk-averse US investor adjusts the shares of a portfolio of short-term nominal domestic and foreign assets to maximize expected utility. The optimal strategy is to respond immediately to all new information which arrives weekly. We calculate the expected utility foregone when the investor abandons the optimal strategy and instead optimizes less frequently. We also consider the cases where the investor ignores the covariance between returns sourced in different countries, and where the investor makes unsystematic mistakes when forming expectations of exchange rate changes. We demonstrate that the expected utility cost of sub-optimal behaviour is generally very small. Thus, for example, if investors adjust portfolio shares every three months, they incur an average expected utility loss equivalent to about 0.16% p.a. It is therefore plausible that slight opportunity costs of frequent optimization may outweigh the benefits. This result may help explain the failure of uncovered interest parity.

Soundfield synthesis with distributed modal constraints

A method is introduced for calculating driving functions for loudspeaker arrays used to control sound fields. This is based on the simultaneous solution of multiple modal constraints whose centres are distributed in space. Several test examples are described. Subjects considered include the control of the complete interior of convex and concave array boundaries, the control of subregions, loudspeaker distributions, open boundaries, independent regions, point source targets, and encoding and decodin

Economics and the marriage wars

We critique the economic analysis of marriage and divorce descending from Becker (1981): we call this the "economic" approach. Marriage is based on the "productive" gains available from specialization in market production and household production, and on the production of children. ln the more recent development of the theory, the husband and wife bargain over the gains. This analysis contrasts with the "covenant" view of marriage which is based on the Judea-Christian tradition. The ethical focus of the covenant view is self-giving love, which is not dependent on economic efficiency. We suggest that the changing attitudes to marriage and divorce in the West may reflect "motivation crowding out," as the economic approach erodes the values underpinning the covenant view. Marriage, like the monarchy over the last three centuries, remains popular in many quarters. But the mere existence of an institution can mask its wholesale transformation

Differential evolution schemes for speech segmentation: A comparative study

This paper presents a signal processing technique for segmenting short speech utterances into unvoiced and voiced sections and identifying points where the spectrum becomes steady. The segmentation process is part of a system for deriving musculoskeletal articulation data from disordered utterances, in order to provide training feedback. The functioning of the signal processing technique has been optimized by selecting the parameters of the model. The optimization has been carried out by testing and comparing multiple Differential Evolution implementations, including a standard one, a memetic one, and a controlled randomized one. Numerical results have also been compared with a famous and efficient swarm intelligence algorithm. For the given problem, Differential Evolution schemes appear to display a very good performance as they can quickly reach a high quality solution. The binomial crossover appears, for the given problem, beneficial with respect to the exponential one. The controlled randomization appears to be the best choice in this case. The overall optimized system proved to segment well the speech utterances and efficiently detect its uninteresting part

The discovery of a highly polarized bipolar nebula

During a search for the optical counterparts of IRAS sources whose flux peaks at 25 microns, a small faint bipolar nebula was discovered in Monoceros at the position of IRAS 07131-0147. The CCD images display the object's considerable structure. The central star seems relatively free of closeby nebulosity: the two lobes have a bow-tie structure with those parts nearest to the star consisting of series of small knots. The outer parts of the lobes seem to be made up of filaments streaming away from knots. On the basis of its optical spectrum, the central star was classified as a M5-6 giant. In the IRAS color classification scheme of Van der Veen and Habing (1988), the central star is VIb which indicates that there are distinct hot and cold components of circumstellar dust and that the mass loss process may have temporarily abated. Therefore, it is proposed that the object is in the post main sequence stage of evolution and is a protoplanetary nebulae. Young protoplanetary nebulae have totally obscured central stars illuminating reflective lobes whereas older ones such as M2-9 have lobes seen in emission from gas ionized by the central hot star which is clearly visible. Since the central object of IRAS07131-0147 is a relatively unobscured late type star and the lobes are seen only by reflection, it is suggested that this nebula is a protoplanetary nebula in an evolutionary stage intermediate between that of CRL2688 and M2-9