Electrode construction Patent

Electrode attached to helmets for detecting low level signals from skin of living creature

Helmet system broadcasts electroencephalograms of wearer

EEG monitoring system consisting of nonirritating sponge-type electrodes, amplifiers, and a battery-powered wireless transmitter, all mounted in the subjects helmet, obtains electroencephalograms /EEGs/ of pilots and astronauts performing tasks under stress. After a quick initial fitting, the helmet can be removed and replaced without adjustments

Constructing Melchior Lorichs's 'Panorama of Constantinople'

In Constructing Melchior Lorichs's Panorama of Constantinople, Nigel Westbrook, Kenneth Rainsbury Dark, and Rene Van Meeuwen propose that Melchior Lorichs's 1559 Panorama of Constantinople was created by using a viewing grid. The panorama is thus a reliable graphic source for the lost or since-altered Ottoman and Byzantine buildings of the city. The panorama appears to lie outside the conventional symbolic mode of topographical depiction common for its period and constitutes a rare "scientific" record of an encounter of a perspicacious observer with a vast subject. The drawing combines elements of allegory with extensive empirical observation. Several unknown structures, shown on the drawing, have been located in relation to the present-day topography of Istanbul, as a test-case for further research

Narrowband, crystal-controlled biomedical telemetry system

Telemetry system utilizing miniature, single-channel, crystal-controlled transmitter is described suitable for biomedical applications. Receiver used in conjunction with transmitter is narrowband superheterodyne FM receiver with crystal control in both conversion stages

Constant-amplitude RC oscillator

Sinusoidal oscillator has a frequency determined by resistance-capacitance /RC/ values of two charge control devices and a constant-amplitude voltage independent of frequency and RC values. RC elements provide either voltage-control, resistance-control, or capacitance-control of the frequency

Estimating returns to scale with large imperfect panels

In this paper, the authors provide systematic panel-based econometric estimates of plant-level returns to scale for various 3-digit and 4-digit manufacturing industries, using panel data for Chilean plants. The paper attempts to answer two questions: 1) Do policies that promote"bigness"in manufacturing plants also promote greater productivity?; and 2) As plants grow, do they become more efficient? The paper is organized as follows. First, the author's assumptions regarding technology and behavior are presented. The following section discusses alternative estimators that deal with different aspects of the econometric problems they faced. Finally, applications of the alternative estimators to various 3-digit and 4-digit industries are reported and an attempt is made to determine which returns to scale estimates are the most reliable.Scientific Research&Science Parks,Science Education,Environmental Economics&Policies,Economic Theory&Research,Statistical&Mathematical Sciences

Non-monotonic variation of stress intensity with flaw size in metal-lined fibre-reinforced pressure vessels

Metal-lined continuous fibre reinforced plastic (FRP) over-wrapped pressure vessels are used in aerospace applications, for storage of breathing air in fire fighting and scuba diving and for the storage of compressed gaseous fuels on natural gas and hydrogen vehicles. Continuous fibres, generally about 15 micro m in diameter and made of glass, carbon or kevlar, are embedded in a polymer matrix. The metallic liner is made of a ductile material - generally steel or aluminum alloy. After the metallic liner has been wrapped, the composite vessel is subjected to a process termed Autofrettage. In that process the vessel is internally pressurized to the point that the ductile metal liner undergoes a small amount of plastic deformation (unlike elastic deformation which disappears upon removal of stress, plastic deformation remains after the stress has been removed). Upon de-pressurization of the vessel, the metallic liner remains under compression and the FRP under tension. Acoustic emissions associated with fiber breakage are being developed currently as a non-destructive means of assessing the structural integrity of metal-lined continuous FRP over-wrapped vessels. Laboratory experiments have been carried out with flaws such as cracks and saw cuts of varying dimensions oriented in an axial-radial plane and located in the metallic liner, in the FRP or in both. Pressurization of the flawed vessel leads to fiber breakage, the extent of which is being examined with the intent that it will be a measure of structural integrity of the vessel. The results, however, suggest that the acoustic emissions attain a maximum for an intermediate flaw size. Low emissions are recorded when on the one hand the vessel has insignificant flaws, or on the other if the vessel has serious flaws. This non-monotonic variation of acoustic emission occurs whether the flaws are located in the metallic liner, in the FRP or in both. The experiments suggest that the stress intensity at the discontinuity (crack tip) attains a maximum at an intermediate flaw size. A mathematical corroboration is desired

Behavioural correlate of choice confidence in a discrete trial paradigm

How animals make choices in a changing and often uncertain environment is a central theme in the behavioural sciences. There is a substantial literature on how animals make choices in various experimental paradigms but less is known about the way they assess a choice after it has been made in terms of the expected outcome. Here, we used a discrete trial paradigm to characterise how the reward history shaped the behaviour on a trial by trial basis. Rats initiated each trial which consisted of a choice between two drinking spouts that differed in their probability of delivering a sucrose solution. Critically, sucrose was delivered after a delay from the first lick at the spouts--this allowed us to characterise the behavioural profile during the window between the time of choice and its outcome. Rats' behaviour converged to optimum choice, both during the acquisition phase and after the reversal of contingencies. We monitored the post-choice behaviour at a temporal precision of 1 millisecond; lick-response profiles revealed that rats spent more time at the spout with the higher reward probability and exhibited a sparser lick pattern. This was the case when we exclusively examined the unrewarded trials, where the outcome was identical. The differential licking profiles preceded the differential choice ratios and could thus predict the changes in choice behaviour.This research was supported by the Australian Research Council Discovery Project Grant DP0987133 to EA

Theory and observations of ice particle evolution in cirrus using Doppler radar: evidence for aggregation

Vertically pointing Doppler radar has been used to study the evolution of ice particles as they sediment through a cirrus cloud. The measured Doppler fall speeds, together with radar-derived estimates for the altitude of cloud top, are used to estimate a characteristic fall time tc for the `average' ice particle. The change in radar reflectivity Z is studied as a function of tc, and is found to increase exponentially with fall time. We use the idea of dynamically scaling particle size distributions to show that this behaviour implies exponential growth of the average particle size, and argue that this exponential growth is a signature of ice crystal aggregation.Comment: accepted to Geophysical Research Letter