Data-matched filter

After amplification and normalization, incoming data bits are fed, alternately, to pair of integrators. While one integrator is operating, content of other is on hold, sample, and dump. Clock derived in bit-timing extractor times and controls integrators. Frequency of clock is one-half data rate

Kinematic analysis of handwriting movements in patients with Alzheimer's disease, mild cognitive impairment, depression and healthy subjects

A variety of studies have demonstrated that motor disorders, parkinsonism and extrapyramidal motor symptoms (EPMS) are common in patients with Alzheimer's disease (AD). Several studies have reported an association of EPMS with severity, progression and poor prognosis of AD. The majority of these studies used clinical assessments for the rating of EPMS. In this study, kinematic handwriting analysis was used to quantify differences in fine hand motor function in patients with probable AD and mild cognitive impairment (MCl, as an assumed initial stage of AD) compared to depressed patients and healthy controls. Both patients with MCl and patients with probable AD exhibited loss of fine motor performance. Movements of AD patients were significantly less regular than those of healthy controls. Copyright (C) 2003 S. Karger AG, Basel

Small-sample asymptotic distributions of M-estimators of location

Asymptotic formulae for the distribution of M-estimators, i.e. maximum likelihood type estimators, of location, including the arithmetic mean, are derived which numerical studies show to give relative errors for densities and tail areas of the order of magnitude of 1% down to sample sizes 3 and 4 even in the extreme tails. The paper is the continuation of earlier work by the second author and is also closely related to Daniels's work on the saddlepoint approximation. The method consists in expanding the derivative of the logarithm of the unstandardized density of the estimator in powers of 1/n at each point, using recentring by means of conjugate distributions. This method yields a unified point of view for the comparison of other asymptotic methods, namely saddlepoint method, Edgeworth expansion and large deviations approach, which are also compared numericall

Results of ultra-low level 71ge counting for application in the Gallex-solar neutrino experiment at the Gran Sasso Underground Physics Laboratory

It has been experimentally verified that the Ultra-Low-Level Counting System for the Gallex solar neutrino experiment is capable of measuring the expected solar up silon-flux to plus or minus 12% during two years of operation

Violation of Equivalence Principle and Solar Neutrinos

We have updated the analysis for the solution to the solar neutrino problem by the long-wavelength neutrino oscillations induced by a tiny breakdown of the weak equivalence principle of general relativity, and obtained a very good fit to all the solar neutrino data.Comment: 3 pages, 5 figures, uses espcrc2.sty, Talk presented by H. Nunokawa at Europhysics Neutrino Oscillation Workshop (NOW2000), Otranto, Italy, September 9-16, 200

Cleaning the USNO-B Catalog through automatic detection of optical artifacts

The USNO-B Catalog contains spurious entries that are caused by diffraction spikes and circular reflection halos around bright stars in the original imaging data. These spurious entries appear in the Catalog as if they were real stars; they are confusing for some scientific tasks. The spurious entries can be identified by simple computer vision techniques because they produce repeatable patterns on the sky. Some techniques employed here are variants of the Hough transform, one of which is sensitive to (two-dimensional) overdensities of faint stars in thin right-angle cross patterns centered on bright (<13 \mag) stars, and one of which is sensitive to thin annular overdensities centered on very bright (<7 \mag) stars. After enforcing conservative statistical requirements on spurious-entry identifications, we find that of the 1,042,618,261 entries in the USNO-B Catalog, 24,148,382 of them (2.3 \percent) are identified as spurious by diffraction-spike criteria and 196,133 (0.02 \percent) are identified as spurious by reflection-halo criteria. The spurious entries are often detected in more than 2 bands and are not overwhelmingly outliers in any photometric properties; they therefore cannot be rejected easily on other grounds, i.e., without the use of computer vision techniques. We demonstrate our method, and return to the community in electronic form a table of spurious entries in the Catalog.Comment: published in A

V2:Performance of the solid deuterium ultra-cold neutron source at the pulsed reactor TRIGA Mainz

The performance of the solid deuterium ultra-cold neutron source at the pulsed reactor TRIGA Mainz with a maximum peak energy of 10 MJ is described. The solid deuterium converter with a volume of V=160 cm3 (8 mol), which is exposed to a thermal neutron fluence of 4.5x10^13 n/cm2, delivers up to 550 000 UCN per pulse outside of the biological shield at the experimental area. UCN densities of ~ 10/cm3 are obtained in stainless steel bottles of V ~ 10 L resulting in a storage efficiency of ~20%. The measured UCN yields compare well with the predictions from a Monte Carlo simulation developed to model the source and to optimize its performance for the upcoming upgrade of the TRIGA Mainz into a user facility for UCN physics.Comment: 23 pages, 8 figure

The Solar Neutrino Problem in the Light of a Violation of the Equivalence Principle

We have found that long-wavelength neutrino oscillations induced by a tiny breakdown of the weak equivalence principle of general relativity can provide a viable solution to the solar neutrino problem.Comment: 3 pages, 1 eps figure, Talk given by R. Zukanovich Funchal at the VIth International Workshop on ``Topics in Astroparticle and Underground Physics'' (TAUP99), Sep. 6-10, 1999, College de France, Paris - Franc

Training teachers for the multimedia age: developing teacher expertise to enhance online learner interaction and collaboration

This article considers the skills that enable teachers to foster interaction and collaboration in online language learning. Drawing on Hampel and Stickler’s (2005) skills pyramid for online language learning and teaching, it presents the pre-service and in-service training programme that associate lecturers in the Department of Languages at the Open University undergo in the context of teaching languages with the help of online communication tools. Two projects are presented that shed more light on the expertise required to teach languages in virtual learning environments. The first project highlights the skills that are needed to teach in a complex online environment; the second one, a teacher training study, aimed to examine distance teachers’ experience of facilitating online group work, identify development needs, try out the potential of specific asynchronous and synchronous tools to support collaborative learning and trial possible development activities. The paper concludes by describing the kind of training programme that tutors require in order to acquire the skills identified