Motion measurement of acoustically levitated object

A system is described for determining motion of an object that is acoustically positioned in a standing wave field in a chamber. Sonic energy in the chamber is sensed, and variation in the amplitude of the sonic energy is detected, which is caused by linear motion, rotational motion, or drop shape oscillation of the object. Apparatus for detecting object motion can include a microphone coupled to the chamber and a low pass filter connected to the output of the microphone, which passes only frequencies below the frequency of sound produced by a transducer that maintains the acoustic standing wave field. Knowledge about object motion can be useful by itself, can be useful to determine surface tension, viscosity, and other information about the object, and can be useful to determine the pressure and other characteristics of the acoustic field

Optimal Galaxy Distance Estimators

The statistical properties of galaxy distance estimators are studied and a rigorous framework is developed for identifying and removing the effects of Malmquist bias due to obsevational selection. The prescription of Schechter (1980) for defining unbiased distance estimators is extended to more general -- and more realistic -- cases. The derivation of `optimal' unbiased distance estimators of minimum dispersion, by utilising information from additional -- suitably correlated -- observables, is discussed and the results applied to a calibrating sample from the Fornax cluster, as used in the Mathewson spiral galaxy redshift survey. The optimal distance estimator derived from I-band magnitude, diameter and 21cm line width has an intrinsic scatter which is 25 \% smaller than that of the Tully-Fisher relation quoted for this calibrating sample. (Figures are available on request).Comment: Plain Latex, 19 pages, Sussex-AST-93/9-

Randomized Smoothing for Stochastic Optimization

We analyze convergence rates of stochastic optimization procedures for non-smooth convex optimization problems. By combining randomized smoothing techniques with accelerated gradient methods, we obtain convergence rates of stochastic optimization procedures, both in expectation and with high probability, that have optimal dependence on the variance of the gradient estimates. To the best of our knowledge, these are the first variance-based rates for non-smooth optimization. We give several applications of our results to statistical estimation problems, and provide experimental results that demonstrate the effectiveness of the proposed algorithms. We also describe how a combination of our algorithm with recent work on decentralized optimization yields a distributed stochastic optimization algorithm that is order-optimal.Comment: 39 pages, 3 figure

BARGAINING FOR EUROPEAN UNION FARM POLICY REFORM THROUGH U.S. PESTICIDE RESTRICTIONS

Future trade negotiations will incorporate environmental concerns. This study presents a framework to evaluate whether the United States would be willing to adopt a pesticide restriction in exchange for European Union liberalization of producer support. It outlines the conditions that must be met if a bargain is to occur. Partial equilibrium commodity models test whether the conditions for a bargaining solution are satisfied. The research results indicate that a potential bargain is possible for stricter U.S. environmental regulations in coarse grains if there is a sufficiently large positive EU externality. Conditions in the oilseed market preclude a bargain.Agricultural and Food Policy,

Interview with John Martin by Mike Hastings

Biographical NoteJohn Lewis Martin was born on June 5, 1941, in Eagle Lake, Maine. At the age of three, his parents moved from Eagle Lake to Brownville Junction; he grew up speaking French and English. Martin was graduated from Fort Kent Community School in 1959 and afterwards spent two years at the University of Maine, Fort Kent before transferring to the University of Maine, Orono, graduating in 1963. While doing graduate work, he was elected to the Maine state legislature as a Democrat in 1964. He served in the Maine House of Representatives from 1964-1994 and was speaker of the house from 1975-1994. During that period, he also held a number of other positions, including teaching at various colleges and high schools in northern Maine and serving as a campaign aide to Senators Edmund S. Muskie and George J. Mitchell. SummaryInterview includes discussion of: working on Muskie’s campaign; the Dubord decision; working with Mitchell on Muskie’s staff; Mitchell’s 1974 gubernatorial campaign; Martin being elected speaker of the house in Maine state legislature; 1968 Muskie Vice Presidential campaign; 1970 Muskie Senate reelection campaign as treasurer; Martin working with Jim Longley; Martin’s reaction when Mitchell was appointed to replace Muskie; Mitchell’s ascent to leadership in the Senate; the importance of the Dickey-Lincoln project to northern Maine; the future of Aroostook County; the size of the legislature and the possibility of a unicameral legislature; and thoughts on Mitchell’s work in the Middle East

British pain clinic practitioners' recognition and use of the bio-psychosocial pain management model for patients when physical interventions are ineffective or inappropriate : results of a qualitative study

Background To explore how chronic musculoskeletal pain is managed in multidisciplinary pain clinics for patients for whom physical interventions are inappropriate or ineffective. Methods A qualitative study was undertaken using semi-structured interviews with twenty five members of the pain management team drawn from seven pain clinics and one pain management unit located across the UK. Results All clinics reported using a multidisciplinary bio-psychosocial model. However the chronic pain management strategy actually focussed on psychological approaches in preference to physical approaches. These approaches were utilised by all practitioners irrespective of their discipline. Consideration of social elements such as access to social support networks to support patients in managing their chronic pain was conspicuously absent from the approaches used. Conclusion Pain clinic practitioners readily embraced cognitive/behavioural based management strategies but relatively little consideration to the impact social factors played in managing chronic pain was reported. Consequently multidisciplinary pain clinics espousing a bio-psychosocial model of pain management may not be achieving their maximum potential