Electrical Engineers, Proceedings of the Institution of

Volume 121 Issue 11 • November 1974

This issue contains several parts.Go to:  Part R

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Displaying Results 1 - 25 of 25
• Binary plot extraction using digital integrating counters

Publication Year: 1974, Page(s):1345 - 1350
| | PDF (693 KB)

Binary plot extraction systems are used in contemporary radar systems as an economical means for providing information on the presence and position of targets, by combining data from all the pulses during one scan of the beam. The paper assesses the performance of two binary plot extraction systems employing digital integrating counters. It is shown how to obtain probability of detection curves fo... View full abstract»

• Surface series-expansion coefficients for numerical design of scannable aspherical microwave and acoustic lenticular antennas

Publication Year: 1974, Page(s):1351 - 1354
Cited by:  Papers (1)
| | PDF (455 KB)

Normalised series-expansion coefficients are presented for the numerical design of the surfaces of extremely short-focal-length/wide angle asperical scanning lens antennas with symmetrical off-axis focal points. Based on theoretical techniques previously developed for the problem, the normalised numerical results presented assume an index of refraction of 1.594 and a fixed off-axis angle of 20Â° f... View full abstract»

• Analysis of centre-line-driven circular-loop antenna

Publication Year: 1974, Page(s):1355 - 1359
Cited by:  Papers (1)
| | PDF (495 KB)

A closed loop antenna being driven through a straight centre lineÂ¿ conductor which bridges the loop at an axis of the symmetry has been considered. This antenna is called the centre-line-driven loop antennaÂ¿. In view of the circuit and radiation properties, this is considered as two closely coupled coplanar loops, compressed into a single loop. By approximation of the antenna current by interp... View full abstract»

• Impedance characteristics of series slots

Publication Year: 1974, Page(s):1360 - 1362
Cited by:  Papers (1)
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The nature of an equivalent network of slots having any arbitrary orientation in the broad wall of a rectangular waveguide, for both even and odd distributions of the aperture field, has been investigated. The complex power radiated by the slot has been determined from the angular spectrum of plane waves. The impedance characteristics of the transverse slot and of the centred inclined slot have be... View full abstract»

• Dipole-type-mode propagation in a rectangular wave guide

Publication Year: 1974, Page(s):1363 - 1366
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The paper describes experimental evidence, supported by a simple theoretical analysis, of a new form of wave inside a rectangular-guide structure, two opposite walls of which present to the field anisotropic impedances. The mode concerned is of dipole pattern, belonging to the surface-wave family, and is not subject to cutoff. It is shown to be a slow wave, and to propagate along a guide of cross-... View full abstract»

• Properties of interface between homogeneous and inhomogeneous waveguides

Publication Year: 1974, Page(s):1367 - 1374
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The interface between empty and dielectric-loaded lossless waveguides is discussed in terms of three independent measurable quantities. A mode-matching technique is used to obtain an equivalent-circuit representation of the junction, when only the dominant mode propagates in each waveguide. The circuit has the form of two equivalent transmission lines, which describe the two waveguides, and a 2-el... View full abstract»

• Analysis of overheads in packet-switched data networks

Publication Year: 1974, Page(s):1375 - 1376
Cited by:  Papers (1)
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Theoretical and simulation results are presented for the overheads in packet-switched networks. These overheads arise owing to the operational spects of the network and `blankÂ¿ padding of the last packet of a message. Message lengths have been assumed to be exponentially distributed. Results indicate good agreement between theoretical and simulation results. It is concluded that overheads can be ... View full abstract»

• Protective scheme for series-compensated transmission lines

Publication Year: 1974, Page(s):1377 - 1384
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The problem of determining fault position on a series-compensated power line is considered and a novel measuring scheme based on definite integrals of relaying current and voltage is described. Attention is given to the effect of travelling-wave distortion of relaying signals in designing a prototype single-phase relay. Details of the equipment construction are given together with laboratory tests... View full abstract»

• New approach to the determination of synchronous-machine parameters from tests

Publication Year: 1974, Page(s):1385 - 1392
Cited by:  Papers (18)
| | PDF (755 KB)

In the last decade or more, a number of tests on large synchronous machines and the associated analytical work have revealed certain inaccuracies in the theory of synchronous-machine performance, which has been used for the last half century. A new look is taken at the assumptions underlying the old theory and several of them are discarded in the derivation of a new theory which corrects many of t... View full abstract»

• Transfer-matrix analysis of linear induction machines with finite width and depth

Publication Year: 1974, Page(s):1393 - 1398
| | PDF (640 KB)

The linear induction machine is considered as a stack of rectangular regions bounded by an impressed excitation. These regions may in general be moving or stationary secondary conductors and iron segments and airgaps. For performance analysis, the field quantities must be evaluated in each region. A wave-impedance approach has previously been successfully applied in cases where lateral edge effect... View full abstract»

• Current pulsation of induction motor driving a reciprocating compressor

Publication Year: 1974, Page(s):1399 - 1403
Cited by:  Papers (3)
| | PDF (498 KB)

With a reciprocating-compressor drive, large errors in the prediction of current pulsation can occur when the induction-motor steady-state characteristics are used in the analytical solution. A numerical solution, in which the induction motor is represented by its general 2-axis equations, is presented, and the results favourably compared with test measurements. The currently used equation for ind... View full abstract»

• Electrostatic fields underneath power lines operated at very high voltages

Publication Year: 1974, Page(s):1404 - 1408
Cited by:  Papers (2)
| | PDF (427 KB)

The intensity of the electrostatic field at ground level due to transmission lines operating at 765, 1100 and 1500kV have been calculated as a function of lateral distance under the line. These results showed that the maximum field varied between 15 and 20kV/m. It was found that this field could be reduced significantly by interposing earth shield wires between the line conductors and earth; the i... View full abstract»

• Damping effects of excitation control in load-frequency control system

Publication Year: 1974, Page(s):1409 - 1416
Cited by:  Papers (2)
| | PDF (664 KB)

A model is developed for a 2-area load-frequency control system, with the inclusion of excitation control in one area and voltage-perturbation input in the other. The change in load demand due to voltage perturbation is considered in both the areas. Optimal-control techniques are applied to this model to determine the optimum response of the system. This response is then compared with that obtaine... View full abstract»

• Discussion on "Overhead-line parameters for circuit-breaker application"

Publication Year: 1974, Page(s):1417 - 1418
| PDF (269 KB)
• Realisation of sinusoidal flux in a transformer-iron sample

Publication Year: 1974, Page(s):1419 - 1420
Cited by:  Papers (1)
| PDF (255 KB)
• Single-phase-induction-motor-reversal transient

Publication Year: 1974, Page(s):1420 - 1421
| PDF (233 KB)
• New technique for quadrilateral distance relay

Publication Year: 1974, Page(s):1421 - 1422
| PDF (248 KB)
• Improved logic model for thyristor

Publication Year: 1974, Page(s):1422 - 1423
| PDF (252 KB)
• Stability problems in the control of multipass processes

Publication Year: 1974, Page(s):1425 - 1432
Cited by:  Papers (22)
| | PDF (945 KB)

The general characteristics of multipass processes are discussed and a method of process modelling is proposed based on the single independent variable: total distance passed. The stability of a number of such processes, including longwall coal cutting, ploughing and metal rolling, is examined using this type of model analysed by the inverse Nyquist technique. Important stability problems, arising... View full abstract»

• Transfer-function evaluation in reduced form

Publication Year: 1974, Page(s):1433 - 1434
| | PDF (210 KB)

A method is presented for calculating the transfer function corresponding to a state-space description so that the numerator and denominator of each element are relatively prime. View full abstract»

• Longitudinal control of automated vehicles in guided transportation systems

Publication Year: 1974, Page(s):1435 - 1440
| | PDF (568 KB)

A detailed system model for a vehicle travelling on an automated mainline guideway under a synchronous moving-cell control philosophy is proposed. The model takes account of position, velocity and acceleration errors as well as the dynamics of the vehicle's propulsion system and the effects of stochastic input disturbances. It is assumed that not all the vehicle's states will be available for meas... View full abstract»

• Proportional-integral derivative realisation of optimal linear-quadratic regulators

Publication Year: 1974, Page(s):1441 - 1443
Cited by:  Papers (3)
| | PDF (361 KB)

The paper presents a new method for the realisation of optimal linear-quadratic regulators, for linear time-invariant systems, using the concept of proportional-integral derivative (p.i.d.) feedback. It is shown that an optimum complete-state-feedback regulator-system response can be alternatively obtained with incomplete feedback, by introducing the derivative-control action. Considering also the... View full abstract»

• Heaviside's 'posthumous papers'

Publication Year: 1974, Page(s):1444 - 1446
| | PDF (457 KB)

An independent search through the Heaviside Collection of the Institution of Electrical Engineers for the material discussed in Heaviside's 'posthumous papers' is reported. View full abstract»

• Low-loss dielectrics for 10ߝ3000 GHz

Publication Year: 1974, Page(s):1447 - 1450
Cited by:  Papers (2)
| | PDF (461 KB)

A new vacuum melting extraction and casting (v.m.e.c.) process for polyolefins has resulted in exceptionally low dielectric losses in the range 10ߝ3000 GHz. At 12.5 GHz, losses in polypropylene have been found to be usually below 30 μ rad and in a few cases as low as 5 μ rad. Measuring techniques have been refined to cope with these low values. Loss angles at 13 and 28 GHz ca... View full abstract»

• Treeing in mechanically strained h.v.-cable polymers using conducting polymer electrodes

Publication Year: 1974, Page(s):1451 - 1456
Cited by:  Papers (12)
| | PDF (996 KB)

An improved laboratory technique for the measurement of tree initiation voltages in polymeric insulation is described, which allows a closer approach to the conditions in extruded cable insulation. The potential importance of using divergent-field electrodes fabricated from polymeric cable screen compound is demonstrated by a reversal of the order of merit of two polymers when screen compound and ... View full abstract»

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The Proceedings of the Institution of Electrical Engineers was published by the IET between 1963 and 1979.

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