Interaction of electronic current with hypersonic waves in solids quarterly progress report no. 3, apr. 1 - jun. 31, 1964

Electronic current interaction with hypersonic waves in cadmium sulfide crysta

Interaction of electronic current with hypersonic waves in solids Technical summary report, 1 Oct. 1963 - 30 Sep. 1964

Current saturation, noise spectrum, low frequency oscillation, radio frequency, and optical measurements in cadmium sulphide when electric field exceeds sound velocit

Electric-arc heater Patent

Magnetically diffused radial electric arc heate

1,3,4,6-Tetramethyl-1,4-dihydro-1,2,4,5-tetrazine, C_6H_(12)N_4

M_r =140∙19, monoclinic, P2_1/n, a = 10∙612(3), b=6∙820(1), c= 10∙975 (2) Å, β=95∙31(2)°, V=790.9(5) Å^3, Z=4, D_m=1.13(5) (flotation), D_x = 1∙177 g cm^(-3), Mo Kα, λ = 0.71073 Å, μ= 0.848 cm^(-1), F(000) = 304, T= 295 K, R = 0∙077 for 704 observed reflections. This potentially antiaromatic or homoaromatic ring system has a flattened boat conformation with both N-methyls in equatorial positions. Bond angles and distances (excluding H's) predicted to be symmetry equivalent exhibit variations of 0.002-0.014 Å and 0.0-2.0°. Substantial delocalization of the electron lone pairs of N(1) and N(4) is found

A magnetically rotated electric arc air heater employing a strong magnetic field and copper electrodes

Magnetically rotated electric arc air heater using strong magnetic field and copper electrode

Small high-temperature nuclear reactors for space power

Criticality calculations for small, cylindrical, lithium cooled reactors for space power system

An Evaluation of Social Grade as a Classification Scheme

Social Grade is a standard classifier that has been questioned by researchers on numerous occasions over the past thirty years but remains a key element of market research. This thesis presents results of research conducted on the discriminatory ability of Social Grade and other commonly used classification systems. A systematic random sample of 2000 records was extracted from the 1989 Target Group Index (TGI) database of British Market Research Bureau. Social Grade and other classifiers were then used as classifiers of household usage, purchase, and ownership of consumer products and services. A variety of statistics were then calculated to evaluate how well Social Grade and the other classifiers could discriminate usage, purchase, and ownership of consumer products and services. Social Grade was shown to clearly provide statistically significant discrimination for; usage and purchase of food products, ownership of consumer durables and use of service products. Social Grade was unable to provide statistically significant discrimination between regular users of different brands of household food products. Social Grade provided low levels of discriminatory power for usage and purchase of food products, consumer durables and service products. Social Grade indicated very poor discriminatory power when used to discriminate brand usage. In general, the other socio-economic, demographic and geo demographic classifiers did provide statistically significant discrimination of the purchase and use of food products, ownership of consumer durables and use of services but did not provide statistically significant discrimination between brands of food products. All these classifiers provided low levels of discriminatory power in all product categories. The implications of this study relate to three main areas in which Social Grading is used. Firstly, Social Grade classification is commonly used as a control variable in sample surveys in stratification, establishing quota controls or post stratification. Secondly, Social Grade is used as a common system of classification in different data sets and, thence, as a linking variable between those data sets. In this situation Social Grade is required to provide consistent sub-groups across many data sources. The final major use of Social Grade is in the analysis of survey information. Social Grade is used to locate concentrations of groups of social or marketing interest or in the discrimination or prediction of behaviour. The results of this study pose many doubts on the suitability of Social Grade in each of these main areas in which it is used

Field theory of the inverse cascade in two-dimensional turbulence

A two-dimensional fluid, stirred at high wavenumbers and damped by both viscosity and linear friction, is modeled by a statistical field theory. The fluid's long-distance behavior is studied using renormalization-group (RG) methods, as begun by Forster, Nelson, and Stephen [Phys. Rev. A 16, 732 (1977)]. With friction, which dissipates energy at low wavenumbers, one expects a stationary inverse energy cascade for strong enough stirring. While such developed turbulence is beyond the quantitative reach of perturbation theory, a combination of exact and perturbative results suggests a coherent picture of the inverse cascade. The zero-friction fluctuation-dissipation theorem (FDT) is derived from a generalized time-reversal symmetry and implies zero anomalous dimension for the velocity even when friction is present. Thus the Kolmogorov scaling of the inverse cascade cannot be explained by any RG fixed point. The beta function for the dimensionless coupling ghat is computed through two loops; the ghat^3 term is positive, as already known, but the ghat^5 term is negative. An ideal cascade requires a linear beta function for large ghat, consistent with a Pad\'e approximant to the Borel transform. The conjecture that the Kolmogorov spectrum arises from an RG flow through large ghat is compatible with other results, but the accurate k^{-5/3} scaling is not explained and the Kolmogorov constant is not estimated. The lack of scale invariance should produce intermittency in high-order structure functions, as observed in some but not all numerical simulations of the inverse cascade. When analogous RG methods are applied to the one-dimensional Burgers equation using an FDT-preserving dimensional continuation, equipartition is obtained instead of a cascade--in agreement with simulations.Comment: 16 pages, 3 figures, REVTeX 4. Material added on energy flux, intermittency, and comparison with Burgers equatio