Proceedings of the Ire Volume 6

Proceedings of the Ire Volume 6

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This historic book may have numerous typos and missing text. Purchasers can usually download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1918 edition. Excerpt: ...having given values T and AQ. It seems admissable to reduce to such a problem that of the most economical charging of a radiotolographic condenser. If the current is i at the time t, this problem consists in fact to determine the minimum value of the integral having a fixed value. In other words, we ought to try to find the shape of wave which gives the maximum square root of the mean square, or effective value, the average value being fixed. It is possible to find the answer by means of the general method which is applicable to such a problem; but we prefer a very elementary solution, which has been already applied by M. Marius Latour for a problem concerning the electric transmission of energy.1 Put: AQ + x. We can immediately write from (2): xdt = 0. Therefore, when substituted in (l): W = R+2RA( xdt+Rlx'dt, the first integral of the second member is zero, and the minimum value of W manifestly occurs when x = constant =0, since the second integral contains only essentially positive elements. Consequently it may be said that the most economical charging for a radiotelegraphic condenser is obtained when the current has a constant value during the whole charging. This value is naturallv: r AQ If we call Q the initial charge of the condenser, the efficiency can be defined by the ratio:: -, or: stored energy + wasted energy 'Cf. Marius Latour, 'L'Eclairage Electrique." February 23, 1901. page 279, number S, volume XXVI. a being the logarithmic decrement, and T the natural period of the circuit. It will be noted that with the Poulsen arc working with oscillations of the 2nd type of M. Blondel, one realizes in practice the charging with a current of constant value by means of the extremely high inductance inserted in the more

Product details

  • Paperback | 80 pages
  • 189 x 246 x 4mm | 159g
  • United States
  • English
  • black & white illustrations
  • 1236954831
  • 9781236954831