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City flight migration patterns in the East Midlands
This paper investigates migration to and from the Three Cities of Derby, Leicester and Nottingham. It investigates whether these cities lose more migrants than they gain from more rural parts of the city-regions and the extent to which these flows impact on the demographic profiles of the Three Cities
Computer program for analysis of split-Stirling-cycle cryogenic coolers
A computer program for predicting the detailed thermodynamic performance of split-Stirling-cycle refrigerators has been developed. The mathematical model includes the refrigerator cold head, free-displacer/regenerator, gas transfer line, and provision for modeling a mechanical or thermal compressor. To allow for dynamic processes (such as aerodynamic friction and heat transfer) temperature, pressure, and mass flow rate are varied by sub-dividing the refrigerator into an appropriate number of fluid and structural control volumes. Of special importance to modeling of cryogenic coolers is the inclusion of real gas properties, and allowance for variation of thermo-physical properties such as thermal conductivities, specific heats and viscosities, with temperature and/or pressure. The resulting model, therefore, comprehensively simulates the split-cycle cooler both spatially and temporally by reflecting the effects of dynamic processes and real material properties
Shell model description of the 14C dating beta decay with Brown-Rho-scaled NN interactions
We present shell model calculations for the beta-decay of the 14C ground
state to the 14N ground state, treating the states of the A=14 multiplet as two
0p holes in an 16O core. We employ low-momentum nucleon-nucleon (NN)
interactions derived from the realistic Bonn-B potential and find that the
Gamow-Teller matrix element is too large to describe the known lifetime. By
using a modified version of this potential that incorporates the effects of
Brown-Rho scaling medium modifications, we find that the GT matrix element
vanishes for a nuclear density around 85% that of nuclear matter. We find that
the splitting between the (J,T)=(1+,0) and (J,T)=(0+,1) states in 14N is
improved using the medium-modified Bonn-B potential and that the transition
strengths from excited states of 14C to the 14N ground state are compatible
with recent experiments.Comment: 4 pages, 5 figures Updated to include referee comments/suggestion
TMS communications hardware. Volume 2: Bus interface unit
A prototype coaxial cable bus communication system used in the Trend Monitoring System to interconnect intelligent graphics terminals to a host minicomputer is described. The terminals and host are connected to the bus through a microprocessor-based RF modem termed a Bus Interface Unit (BIU). The BIU hardware and the Carrier Sense Multiple Access Listen-While-Talk protocol used on the network are described
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