Plurality-count Diversity Combining for Fading M-ary Transmissions

Plurality-count Diversity Combining for Fading M-ary Transmissions
Author: John N. Pierce
Publisher:
Total Pages: 38
Release: 1965
Genre: Alphabets
ISBN:

The performance of a plurality-count diversity combiner for fading M-ary transmissions is analyzed, and calculated error probabilities are presented graphically for alphabet sizes of 2, 8, and 32. The performance is shown to be within 3 dB of that of an optimum square-law combiner for moderate alphabet sizes when there is no restriction on the allowable number of diversity branches. It is shown that a worthwhile saving in transmitted power can be effected by using nonbinary alphabets with plurality-count combining for the transmission of binary data. The availability of extra information from the combiner for use with error-correction is discussed.

Electrophoretic Power Generation in Thermally Ionized Plasmas

Electrophoretic Power Generation in Thermally Ionized Plasmas
Author: C. C. Leiby (Jr.)
Publisher:
Total Pages: 42
Release: 1965
Genre: Electrophoresis
ISBN:

Druyvesteyn's solutions for electrophoretically induced gas flows in electrical discharges in gases were extended over a larger pressure range and corrected for the influence of Debye shielding effects. The effects of molecular or 'slip' flow were also taken into account. These more accurate and general solutions were applied to the reverse phenomenon of space charge field generation arising from the flow of a thermally ionized cesium plasma through a tube. Under such flow conditions, a non-linear differential equation for the axial pressure distribution was obtained but not solved. However, it was possible to obtain estimates of the ranges of cesium pressure, temperature and tube radii which would be required for sensible levels of electric power generation. Anaphoretic flow power levels of the order of 0.1 to 10 watts, in tubes of laboratory dimensions (radii of 10 cm or less), appear feasible at temperatures from 1700 to 2400K. Sensible power generation levels at lower temperatures require very large diameter tubes, and therefore are not feasible. (Author).

On the Theory of Boolean Formulas

On the Theory of Boolean Formulas
Author: Lorenzo Calabi
Publisher:
Total Pages: 50
Release: 1965
Genre: Algebra, Boolean
ISBN:

Substitution operators for subformulas of Boolean formulas are introduced and investigated.

An Evaluation of an Important Advance in Network Synthesis Theory

An Evaluation of an Important Advance in Network Synthesis Theory
Author: E. Folke Bolinder
Publisher:
Total Pages: 34
Release: 1965
Genre: Electric circuits
ISBN:

A discussion of a recent significant advance in network synthesis theory is presented. This 'breakthrough' was accomplished by D. Hazony of the Case Institute of Technology and by D. C. Youla of the Polytechnic Institute of Brooklyn, who independently of each other developed methods for unifying the theory of two-port cascade synthesis. Both methods are based on Richards' theorem, and both introduce the gyrator artificually. Different methods of proof are used, however. A valuable 'cookbook recipe' was developed by Youla. Hazony managed to extend the method to n-ports. In all, this epoch-making achievement has resulted in an important, simple, and beautiful method of network synthesis. (Author).

Feasible Control Computations Using Dynamic Programming

Feasible Control Computations Using Dynamic Programming
Author: Stephen J. Kahne
Publisher:
Total Pages: 30
Release: 1965
Genre: Control theory
ISBN:

The application of Bellman's dynamic programming technique to realistic control problems has generally been precluded by excessive storage requirements inherent in the method. In this paper, the notion of state mobility is described and shown to be valuable in reducing certain classes of dynamic programming calculations to manageable size. The scheme requires one simple calculation at each stage of the process. IN many cases even this calculation may be omitted. It results in the reduction of the range of allowable state variables to be scanned. The amount of reduction varies from problem to problem. A simple example exhibits a fifty percent reduction. This corresponds to a fifty percent reduction in storage requirements for the problem. Reductions of one or two orders of magnitude appear possible for certain classes of problems.

Theory of Continuous Zone Refining Via the Zone-transport Method

Theory of Continuous Zone Refining Via the Zone-transport Method
Author: John K. Kennedy
Publisher:
Total Pages: 22
Release: 1964
Genre: Equations of state
ISBN:

This paper explains the differences and the reasons for the differences which exist between the theory of the zone-transport system of continuous zone refining as presented by W. G. Pfann and T. Abe. The identity between the mathematical model used to describe the zone-transport system and one of the models used to describe the recently reported matter-transport system is noted. Nondimensional equations for the zone-transport system are presented and the difference between the limit of alpha in the zone-void and zonetransport systems, when L sub e = 0, is correlated. (Author).