The Corralitos Observatory program for the detection of lunar transient phenomena

This is a final report on the establishment, observing procedures, and observational results of a survey program for the detection of lunar transient phenomena (LTP's) by electro-optical image conversion means. For survey, a unique detection system with an image orthicon was used as the primary element in conjunction with a 24-in. f/20 Cassegrainian telescope. Observations in three spectral ranges, with 6,466 man-hours of observing, were actually performed during the period from October 27, 1965, to April 26, 1972. Within this entire period, no color or feature change within the detection capabilities of the instrumentation was observed, either independently or in follow up of amateur LTP reports, with the exception of one general bluing and several localized bluings (probably ascribable to the effects of the terrestrial atmosphere) that were observed solely by the Corralitos system. A table is presented indicating amateur and professional reports of LTP's and the results of efforts to confirm these reports through the Corralitos system

Regulatory Reform and the National Energy Board

Government regulation has been increasing rapidly for the past five decades. At present, boards, commissions, and other variously named administrative agencies pervade nearly every phrase of the nation\u27s economic and social activity. At the federal level, these groups are involved in formulating economic policy; they control the construction and operation of pipelines and other means of transport; they supervise most facets of the telecommunications and broadcasting industries; they regulate, in many ways, the exploration for and manufacturing and marketing of raw materials. At the provincial level, they are concerned with labour relations, education, and the use of property. In addition, an assortment of fire marshalls, engineers, inspectors, and registrars are among those who operate under municipal ordinances to maintain property according to certain guidelines, to regulate how and where structures will be built and maintained and, in many circumstances, to control how, when, and where individuals may operate businesses

A robust method for measuring the Hubble parameter

We obtain a robust, non-parametric, estimate of the Hubble constant from galaxy linear diameters calibrated using HST Cepheid distances. Our method is independent of the parametric form of the diameter function and the spatial distribution of galaxies and is insensitive to Malmquist bias. We include information on the galaxy rotation velocities; unlike Tully-Fisher, however, we retain a fully non-parametric treatment. We find $H_0=66\pm6$ km/s/Mpc, somewhat larger than previous results using galaxy diameters.Comment: 4 pages, 1 figure, Cosmic Flows Workshop, Victoria B.C. Canada, July 1999, ed. S. Courteau, M. Strauss & J. Willick, ASP conf. serie

Microlensing of Extended Stellar Sources

We investigate the feasibility of reconstructing the radial intensity profile of extended stellar sources by inverting their microlensed light curves. Using a simple, linear, limb darkening law as an illustration, we show that the intensity profile can be accurately determined, at least over the outer part of the stellar disc, with realistic light curve sampling and photometric errors. The principal requirement is that the impact parameter of the lens be less than or equal to the stellar radius. Thus, the analysis of microlensing events provides a powerful method for testing stellar atmosphere models.Comment: 4 pages LaTeX, to appear in New Astronomy Reviews - proceedings of the Oxford Workshop `Gravitational Lensing: Nature's Own Weighing Scales'. Uses elsart.cls. Paper also available at ftp://info.astro.gla.ac.uk/pub/martin/extended.p

Intensity dependences of the nonlinear optical excitation of plasmons in graphene

Recently, we demonstrated an all-optical coupling scheme for plasmons, which takes advantage of the intrinsic nonlinear optical response of graphene. Frequency mixing using free-space, visible light pulses generates surface plasmons in a planar graphene sample, where the phase matching condition can define both the wavevector and energy of surface waves and intraband transitions. Here, we also show that the plasmon generation process is strongly intensity-dependent, with resonance features washed out for absorbed pulse fluences greater than 0.1 J m−2. This implies a subtle interplay between the nonlinear generation process and sample heating. We discuss these effects in terms of a non-equilibrium charge distribution using a two-temperature model.Peer ReviewedPostprint (author's final draft

Hot phonon decay in supported and suspended exfoliated graphene

Near infrared pump-probe spectroscopy has been used to measure the ultrafast dynamics of photoexcited charge carriers in monolayer and multilayer graphene. We observe two decay processes occurring on 100 fs and 2 ps timescales. The first is attributed to the rapid electron-phonon thermalisation in the system. The second timescale is found to be due to the slow decay of hot phonons. Using a simple theoretical model we calculate the hot phonon decay rate and show that it is significantly faster in monolayer flakes than in multilayer ones. In contrast to recent claims, we show that this enhanced decay rate is not due to the coupling to substrate phonons, since we have also seen the same effect in suspended flakes. Possible intrinsic decay mechanisms that could cause such an effect are discussed.Comment: 4 pages, 3 figure

Can patient characteristics explain variance in ultrasound strain elastography measures of the quadratus femoris and patellar tendons?

Objectives To explore the associations between participant characteristics and magnitudes of difference in paired elastography measures of knee tendon from different ultrasound systems, and to compare strain elastography pattern description. Materials and Methods Quadriceps and patellar tendons of 20 healthy volunteers (40 tendons) were examined by an experienced operator employing two ultrasound systems (GE S8 and Esaote MyLab 70XVG). Pearson/Spearman correlations explored the influence of participant characteristics (BMI, body fat %, leg circumference, activity level) on the magnitude of differences between measures. Paired-sample t test or Wilcoxon signed rank test were performed to compare repeated measures of individual ultrasound systems. Results The quadriceps tendon was characteristically stiffer than the patellar tendon. Participant characteristics were associated with within machine differences of the distal quadriceps tendon (BMI; r = 0.49, p = 0.028–0.03 and body fat %; r = 0.43, p = 0.05–0.056) ER measures. Conclusions Anthropometric and body composition parameters were associated with within machine differences for elasticity measures, where high BMI and body fat % contribute to paired measurement variance at the distal quadriceps tendon. Strain elastography protocols should be standardised, repeated ER measures performed using the same US system and patient characteristics considered for future clinical applications

Can a workspace help to overcome the query formulation problem in image retrieval?

We have proposed a novel image retrieval system that incorporates a workspace where users can organise their search results. A task-oriented and user-centred experiment has been devised involving design professionals and several types of realistic search tasks. We study the workspace’s effect on two aspects: task conceptualisation and query formulation. A traditional relevance feedback system serves as baseline. The results of this study show that the workspace is more useful with respect to both of the above aspects. The proposed approach leads to a more effective and enjoyable search experience