ISSN:0021-8979    

DOI:10.1063/1.1707268

出版商:AIP    

年代:1939

数据来源: AIP

ISSN:0021-8979    

DOI:10.1063/1.1707269

出版商:AIP    

年代:1939

数据来源: AIP

ISSN:0021-8979    

DOI:10.1063/1.1707270

出版商:AIP    

年代:1939

数据来源: AIP

摘要:

Starting with the energy functions of a general, linear, bilateral, resistanceless, lumped network the canonical equations of the circuit are obtained. These equations are solved in a general form taking into account applied electromotive forces and initial charges and currents by a matrix multiplication process. It is shown how the matrix multiplication process replaces the usual ``frequency equation'' which determines the normal modes of the system. Initial charges and currents in the various component parts of the network are considered for generality. The method given appears to have some computational advantages in certain classes of problems over the method of the ``Heaviside calculus.'' The discussion is concluded with a discussion of normal coordinates and an illustrative numerical example is given. Since oscillatory networks are used extensively in communication engineering it is hoped that the present discussion will be of value. Since, if the circuit has a small amount of resistance present it may be shown that periods of oscillation are affected only by the squares of small quantities, it is seen that the method given is applicable to many technical problems. A method is given by which the attenuation due to the presence of small resistances in the system may be readily calculated.

ISSN:0021-8979    

DOI:10.1063/1.1707271

出版商:AIP    

年代:1939

数据来源: AIP

摘要:

The author's theory of elasticity of the second order is being applied to calculate the increase of torsional stiffness of a prismatical bar when an axial tension is initially imposed upon it. It is found that the classical shear stress distribution is not affected by the axial stress. However, an increase of torsional stiffness is produced due to the fact that the boundary condition over the cross section contains not only the shearing stress but also the product of the axial stress by the rotations. This increase of torsional stiffness turns out to be proportional to the polar moment of inertia of the cross section with respect to its center of gravity.

ISSN:0021-8979    

DOI:10.1063/1.1707272

出版商:AIP    

年代:1939

数据来源: AIP

摘要:

The principles governing the oscillations in a klystron may be divided into four groups: (1) those of space resonance within each rhumbatron, previously discussed by Hansen; (2) the equations of coupled circuits, with modifications appropriate to space‐resonant systems; (3) the kinematics and dynamics of cathode‐ray bunching, previously discussed by the author; (4) the constraint on phase relations between the rhumbatrons introduced by the cathode‐ray bunches. It is shown here that (4) makes the oscillations assume forms very different from those familiar in free oscillations. These forms are described by general equations and then these equations are applied to three specific problems: maximizing the power output from an oscillator, minimizing the power input for an ideal regenerative amplifier, and finding how stable the frequency is against changes in cathode potential.

ISSN:0021-8979    

DOI:10.1063/1.1707273

出版商:AIP    

年代:1939

数据来源: AIP

摘要:

The extremely finely detailed drawing in Lichtenberg figures offers an unusually clear record of the early stages of discharge phenomena. The interpretation of these records in terms of electronic ionization, space charge, plasma formation, and neutralization of charges is presented in this paper. After giving a short summary of our present knowledge about gas breakdown, the ``normal'' history of a Lichtenberg discharge is established by a study in nitrogen between five millimeters of mercury and thirty atmospheres of pressure. It progresses in three stages—the primary figure, spark development, and the discharge of negative surface charges. (The ``back figure.'') Admixture of carbon tetrachloride and experiments in ``Freon'' up to six atmospheres show the decisive influence of electro‐negative components on the development of the phenomena, and reveal the reasons why these new gases are so effective in suppressing corona discharges. Deviations from Paschen's law, recently observed by several workers, can be interpreted in terms of the photographic evidence gained.

ISSN:0021-8979    

DOI:10.1063/1.1707274

出版商:AIP    

年代:1939

数据来源: AIP

ISSN:0021-8979    

DOI:10.1063/1.1707275

出版商:AIP    

年代:1939

数据来源: AIP

摘要:

That difficulties in the use of various types of pressure gauges warrant meticulous scrutiny in the rendering of an accurate pressure‐time curve has advanced each type of gauge for particular work. In powder gas and internal combustion engine gas pressures the spring type and piezoelectric type offer great possibilities with the first a self‐contained unit and the latter a charge‐collecting device, and with the former following the true curve by an admitted time lag and the latter assumed to be responding instantaneously. Sparse comparative records of the two show the case to be more nearly the reverse of what the popular assumption leads one to believe. Fuller data are needed to determine the comparative lagging characteristics of both types.

ISSN:0021-8979    

DOI:10.1063/1.1707276

出版商:AIP    

年代:1939

数据来源: AIP