A four-transistor peak detector read-out system for digital magnetic surface recording systems

Straightforward amplitude threshold read-out systems fail at low packing densities in non-return-to-zero recording systems. Several elaborate systems have been designed as a remedy. The present circuit is a very much simplified version which operates satisfactorily, using the regenerative action within a flip-flop to detect the change in current polarity occurring at the peak in a voltage differentiator.     

Sphalerite geothermometry

Kullerud’s method of formation-temperature determination has been applied to the polymetallic sulphide deposits of Sadon in Northern Caucasus, U.S.S.R. The sulphide ore occurs at three places, separated by a few kilometers from each other. They are Sadon, Zgid and Holst. Mineralogical assemblage is sphalerite, galena, pyrite and pyrrhotite. It is found that sphalerites from the above three places were formed mainly within a temperature range of 120–500° C. The temperature data are represented in the form of histograms. The occurrence of more than one maximum in each histogram may indicate ore deposition in more than one stage. From the histograms, it is concluded that in Sadon, ore deposition took place in three stages: in Zgid, in only one stage and in Holst, in two stages. These conclusions are in agreement with those arrived at by others by mineragraphic studies.     

A Comment on: Forecasting and Stock Control for Intermittent Demands

Journal of the Operational Research Society -     

Ground state of liquid helium-3: off-shell effects due to non-local potentials

It is shown that by incorporating the off-shell effects through the introduction of phase equivalent nonlocal potentials, (that are essentially equivalent so far as two-body properties are concerned) one could obtain a much better agreement regarding the important properties of the ground state of liquid helium-3, in lowest order Brueckner-Goldstone theory. The binding energy, equilibruim density and the convergence character of Brueckner-Goldstone series improve drastically.