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The maximum average mutual information in the observation of the output, y(t) , of a channel over the time interval [T_3,T_4] about the signal (input), s(t) , in the interval [T_1, T_2] is taken as the definition of channel capacity for the time-continuous case. In the case where the channel introduces additive Independent Gaussian noise of known correlation function, the capacity is evaluated subject to the constraint that the signal process have a given correlation function. For this evaluation a new joint expansion of the processes y(t) and s(t) is introduced which has the property that all coefficients in the expansion are uncorrelated. Thus, the expansion is a generalization of the Karkunen-Lo'{e}ve expansion to which it reduces when the noise is white and the time intervals coincide. The channel capacity is shown to be directly related to results in the theory of optimum filtering over a finite time interval. Closed form results for the capacity of several channels are given as well as some limiting expressions and bounds. For the case of white noise of spectral density N_o , the capacity is always bounded by \bar{E}/N_o where \bar{E} is the average signal energy.

Hypernuclear binding energies obtained from 43 uniquely identified mesic decays are reported here. The values are in good agreement with the previous data. Reported also are binding energies of two short-range mesic spallation hyperfragments.

Measurements were taken of the viscoelastic properties of six polymer melts by mean of the Weissenberg rheogoniometer and the Han slit/capillary rheometer. Polymers in vestigated were three high-density polyethylenes of different polydispersity, a low-density polyethylene, a polypropylene, and a polystyrene. The range of shear rates tested was from about 5.0 × 10−3 to 10 sec−1 with the Weissenberg rheogoniometer, from about 10 to 102 sec−1 with the slit rheometer, and from about 102 and 103 with the capillary rheometer: the temperature of measurement was 200°C. The three different apparatuses give consistent results over almost six decades of shear rates, yielding satisfactory correlations of shear viscosity to shear rate and of normal stress difference to shear rate.

Shannon's definition for the information content of a Gaussian, time-continuous process in Gaussian noise is extended to the case where the observation interval is finite, and where the processes may be nonstationary, in a straightforward way. The extension is based on a generalization of the Karhunen-Loeve Expansion, which allows both the signal and noise processes to be expanded in the same set of functions, with uncorrelated coefficients. The resultant definition is consistent with that of Gel'fand and Yaglom, and avoids the difficulties posed by Good and Doog to Shannon's original definition. This definition is shown to be useful by applying it to the calculation of the information content of some cases of stationary signals in stationary noise, with different spectra, and to one case where both are nonstationary. Limiting relations are derived, to show that this reduces to previously established results in some cases, and to enable one to obtain rule-of-thumb estimates in others. In addition, both the matched filter and the Wiener filter are related to the information; the matched filter in a very direct way, in that it converts a time-continuous process to a set of random variables while conserving the information.

INTRODUCTION NATURAL barriers, as proposed by Dobzhansky (1951) and Riley (1952), have effectively isolated most species and prevented mating, so that although numerous hybrids from natural mating have been reported (Gray, 1958) other hybrids have resulted only when man has affected mating by artificial techniques. Among the latter is the cross between the chicken and the Japanese quail, recently reported by Wilcox and Clark (1961). This paper reports on fertility and hatchability results from artificial crossing of the red jungle fowl (Gallus bankiva) with the Japanese quail (Coturnix japonica), and on some factors involved in the production of such hybrids. MATERIAL AND METHODS Birds used in the experiments were Japanese quail and the red jungle fowl. The quail, hatched in the fall of 1959, and the jungle fowl, hatched in the spring of 1959, were brooded in insulated quarters and transferred at six weeks of age to specially constructed cages…

A modification to the Weissenberg rheogoniometer has been developed. This development makes it possible to measure continuously shear stress-shear rate flow curves for newtonian, time independent non-newtonian and time dependent non-newtonian fluids. Data determined with the modified unit are precise, reproducible and accurate (+or-1%). The modification represents a less expensive and more versatile development than any to date. In addition ranges of capability are greatly extended. Finally, times required for experimentation can be reduced by order of magnitude with the modification.