A Survey of the Arithmetical Concepts of Children in the Elementary Grades Pertaining to the Use of Money

It was the purpose of this study: (1) to survey the present concepts of money and its use, in a specific elementary grade level, in a cross section of a city that included all socio-economic levels; (2) to determine the extent to which knowledge of economic concepts is related to socio-economic level; and (3) make suggestions as to areas where greater emphasis towards understanding of money concepts should be placed

Non-Isothermal Mercury Pipe Flow Turbulent Characteristics

The turbulence structure of fully-developed mercury pipe flow, with and without heat transfer, was studied using hot-film anemometry at Reynolds number of approximately 50,000. Single sensors and slanted multiple sensors were used to obtain the radial distribution of axial fluctuating velocity and temperature quantities. Isothermal data were generally in good agreement with comparable air data indicating similar velocity structure. Temperature intensity data agreed with other data in liquid metals. Axial and radial turbulent heat flux results were somewhat inconclusive. Spectra and turbulence scales were developed providing a picture of the structure

Joule heat calculations for simulations of multielectrode glass melters and in situ vitrification systems

A procedure is developed for calculating Joule heating power density in simulating multielectrode, multiphase, generalized waveform electrically heated glass melters and in situ vitrification systems. A superposition principle valid at low frequencies allows calculating the cycle-averaged power density from a set of potential amplitude solutions, each solution having a current source amplitude in one electrode and a current sink amplitude in another electrode of a driven electrode pair. The calculated cycle-averaged power density can be coupled to balance equations for flow and energy in molten glass or soil. The procedure has advantages over the complex harmonic form for analyzing systems having waveforms chopped by silicon controlled rectifiers. A Scott-T transformer configuration with two emfs driving diagonally opposite electrodes in a rectangular array is one configuration having practical significance. Symmetries of this configuration are affected by amplitudes, phase relations, and waveforms of the electrical driving