Showing papers in "Electrical Engineering in 1961"
Journal Article•
TL;DR: A new recording technique is described that is practically instantaneous, providing storage densities up to 40 million bits of information per square inch, and both image as well as sequential information can be recorded.
Abstract: A new recording technique is described that is practically instantaneous, providing storage densities up to 40 million bits of information per square inch. Frequency response exceeds 40 mc and both image as well as sequential information can be recorded. Its versatility and practicality are illustrated by noting its broad field of application.
28 citations
TL;DR: A general method for analyzing film-type networks, built around the theory of indefinite matrices, is presented and simple rules are developed for generating subnetworks from a given 4-terminal network.
Abstract: An important microminiaturization technique is that of realizing complex network components by means of resistive and dielectric films. A general method for analyzing these film-type networks, built around the theory of indefinite matrices, is presented and simple rules are developed for generating subnetworks from a given 4-terminal network.
26 citations
TL;DR: A brief history of the early days of the transformer's development is presented in this paper, where the first commercial installation of a transformer was celebrated 75 years ago, and the first transformer was installed in a commercial building.
Abstract: Last year marked the 75th anniversary of the first commercial installation of the transformer. In this article a brief history of the) early days of the transformer's development is presented.
19 citations
TL;DR: In this article, the main benefit of superconductivity is increased efficiency and reduction in transformer size, which is the main reason for the need for superconductors in the refrigerator.
Abstract: Increased efficiency is the main benefit of superconductivity. Some power is needed to operate the refrigerator but it is extremely small. Reduction in transformer size is also important. Other advantages include an improvement in power factor, extended life, and automatic limiting of short circuits.
16 citations
TL;DR: In this paper, the evaluation of message circuit noise has been an important problem from the earliest days of telephony and of particular interest has been the evaluation that noise originating from harmonic components present in power system voltages and currents.
Abstract: From the earliest days of telephony the evaluation of message circuit noise has been an important problem. Of particular interest has been the evaluation of noise originating from harmonic components present in power system voltages and currents. Magnetic fields set up by power currents, and electric fields set up by power voltages, tend to induce voltages in nearby telephone conductors. Even a small transfer of power at harmonic frequencies in the voice band can cause trouble. For example an input of 400 ?watts (micromicrowatts), or 26 db (decibels) above reference noise, into a telephone set at 1,000 cps (cycles per second) will give an audible tone. To put such a tone on all of the 60 million telephones in the United States at once would require just 24 milliwatts, transmission losses neglected.
14 citations
TL;DR: This article summarizes several general approaches to automatic regulation and economy dispatch that have evolved in recent years and suggests a system of classifying them by their basic scope and method.
Abstract: This article summarizes several general approaches to automatic regulation and economy dispatch that have evolved in recent years and suggests a system of classifying them by their basic scope and method.
12 citations
TL;DR: In this article, the authors compared the performance of systems with primary distribution of 4.16 and 12.5 kv, as well as the more recently introduced higher voltages of 20.8 to 34.5kv, with load densities varying from 1,000 to 32,000 kva per square mile.
Abstract: Cost comparisons are given for systems with primary distribution of 4.16 and 12.5 kv, as well as the more recently introduced higher voltages of 20.8 to 34.5 kv. Load densities varying from 1,000 to 32,000 kva per square mile are considered in the study.
11 citations
TL;DR: In this paper, a new hard-soldered structure is described which has been proved by long experience to eliminate fatigue failure completely in soft-ssoldered silicon devices, and it is shown that this limitation in life is due to fatigue rupture of the soft soldered joints when subjected to cyclic thermal stress.
Abstract: Germanium devices, when correctly used, are capable of essentially infinite life. It was commonly assumed in early higher temperature semiconductor work that silicon devices and those of materials, such as silicon carbide and III-V compounds would have similar life expectancy. That this is not realized in soft-soldered silicon devices is now well established. Evidence is presented to show that this limitation in life is due to fatigue rupture of the soft-soldered joints when they are subjected to cyclic thermal stress. A new hard-soldered structure is described which has been proved by long experience to eliminate fatigue failure completely.
10 citations
TL;DR: In this article, the authors present a preliminary study and evaluation of ELD transmission, which involves the following assumptions and constraints: 1. Series and shunt compensating elements are applied in the pi configuration, and conmplete shunt compensation of the line sections is assumed.
Abstract: In a preliminary study and evaluation of ELD transmission, it is desirable to have available a general but relatively simple method of estimating the magnitudes and interrelationships of the principal factors and variables. More detailed planning or design would, of course, require refinements and closer examination of operating and equipment limitations. The method incorporated in this paper involves the following assumptions and constraints: 1. Series and shunt compensating elements are applied in the pi configuration, and conmplete shunt compensation of the line sections is assumed. 2. Line loading or capability is based on a displacement angle of 30 degrees between the high-side terminal voltages. 3. Terminal power factors at the two ends are held at equal values, leading at the receiving end and lagging at the sending end. 4. Sending and receiving end terminal voltage magnitudes are restricted so that their geometric mean is equal to the nominal line voltage. The following general conclusions arise from the results of applying these restrictions to the studies reported herein, and these, in turn, prompt some comments and conjecture on the problems and prospects of ELD transmission in the range of 600 miles and beyond. 1. When unit transmission costs are considered in mills per kwhr, ELD transmission inherently calls for the utilization of EHV. 2. In ELD transmission, shunt compensation is required to control voltage conditions, and economic considerations dictate the use of relatively heavy series compensation, up to 80% and above. 3.
10 citations
TL;DR: In this article, a system of coils receiving a rapid transfer of energy from large capacitor banks storing large quantities of energy is described, and the problems involved fall within the compass of electrical engineering analysis and can best be solved by the engineer in his normal work environment.
Abstract: To contain and heat the deuterium plasma used in fusion experiments, strong magnetic fields are necessary. Fields are produced by a system of coils receiving a rapid transfer of energy from large capacitor banks storing large quantities of energy. The problems involved fall within the compass of electrical engineering analysis and can best be solved by the engineer in his normal work environment.
10 citations
TL;DR: In this paper, the authors consider two questions to consider when applying an autotransformer: is the tertiary winding needed, and if needed, what should be its size?
Abstract: AUTOTRANSFORMERS in power systems are usually Y-connected and commonly have delta-connected tertiary windings. Is the tertiary winding needed? If needed, what should be its size? These are two questions to consider when applying an autotransformer.
TL;DR: A satisfactory radio influence level (RIL) can be achieved in a 345-kv transmission line using 945-MCM ACSR conductor bundled at 18-inch spacing, standard clamps, triangular space plates, and a horizontal phase spacing of 27 feet as discussed by the authors.
Abstract: A satisfactory radio-influence level (RIL) can be achieved in a 345-kv transmission line using 945-MCM ACSR conductor bundled at 18-inch spacing, standard clamps, triangular space plates, and a horizontal phase spacing of 27 feet. Attenuation tests show that RI readings at one site are not materially affected by precipitation on the line a few miles away The Ohio Edison Company conducted laboratory tests (previous to the construction of 70 miles of the 345-kv line) to determine the corona and RI levels of the line hardware to be used on its 345-kv transmission lines and has conducted field tests on the completed transmission line to evaluate the selection of hardware. On January 31, 1961, the Sammis-Star North 345-kv transmission line was energized for RI testing; see Figs. 1 and 2. The tests ran for approximately 8 weeks.
TL;DR: In this article, the ratio of asymmetric to symmetric rms current for the first current loop, for different values of power factor of the circuit, and for varying points of short-circuit initiation on the voltage wave has been evaluated accurately.
Abstract: THE value of the ratio of asymmetric to symmetric rms current is an important parameter in the evaluation of asymmetric current effects on electric protective devices. For the simple resistance-reactance circuit (Fig. 1), the ratio of asymmetric to symmetric rms current, for the first current loop, for different values of power factor of the circuit, and for varying points of short-circuit initiation on the voltage wave has been evaluated accurately. The instants of short-circuit initiation on the voltage wave which lead to the maximum values of the ratio of asymmetric and symmetric rms current for different power factors of the circuit can also be found.
TL;DR: Analog-to-digital conversion consists of both sampling and quantizing, an operator that assigns a value to a variable equal to its closest integer.
Abstract: QUANTIZATION, or round-off, takes place whenever physical quantities are represented numerically A quantizer is an operator that assigns a value to a variable equal to its closest integer Analog-to-digital conversion consists of both sampling and quantizing
TL;DR: In this paper, an analysis of the character of natural light at dusk and dawn is presented, and criteria for control of street lights are defined so that the user may evaluate the control devices to best advantage.
Abstract: The use of photoelectric devices to control street lights has grown rapidly in recent years. Many new types of devices have been developed but, in several areas, there is uncertainty as to how they can best be used. An analysis of the character of natural light at dusk and dawn is presented, and criteria for control of street lights is defined so that the user may evaluate the control devices to best advantage.
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TL;DR: The ruby maser as discussed by the authors is a solid-state device that utilizes the principles of microwave amplification by stimulated emission of radiation (maser), which is used to transmit vast amounts of information from one point to another.
Abstract: A brief description is presented of a solid-state device, a ruby maser, that utilizes the principles of microwave amplification by stimulated emission of radiation (maser). Experiments under way point to a new medium of communication in which a beam of light is used to transmit vast amounts of information from one point to another.
TL;DR: The molecular electronics approach to microsystems considers the electronic function to be performed, then attempts to synthesize its characteristics within a suitable solid material as discussed by the authors, and it is expected that this approach will lead to many new concepts in the realization of electronic functions.
Abstract: The molecular electronics approach to microsystems considers the electronic function to be performed, then attempts to synthesize its characteristics within a suitable solid material. It is expected that this approach will lead to many new concepts in the realization of electronic functions.
TL;DR: Because the heart is a dynamic system whose rate changes with stimuli and time, it lends itself well to study by means of the analog computer.
Abstract: Because the heart is a dynamic system whose rate changes with stimuli and time, it lends itself well to study by means of the analog computer. Experiments have been made on both the steady-state and dynamic response of the heart to vagal and sympathetic nerve stimulation The human heart is a very complex muscle-pump system which is controlled from several different areas of the body and by many factors. Because of the experimental difficulties and the complexity of the system itself, no complete mechanical or electrical model of the system has been constructed.
TL;DR: In this paper, the revealed differences between concrete and abstract quantities and units require separate names to avoid any ambiguity and the origin of these differences is clarified but the author contends that new names are not justified.
Abstract: The discussion, begun by F B Silsbee,1 is continued on the question whether the revealed differences between concrete and abstract quantities and units require separate names to avoid any ambiguity The origin of these differences is clarified but the author contends that new names are not justified
TL;DR: In this article, a permanent-magnet slab is used as a counterbiasing means instead of an air gap, and the magnetic operating point is shifted toward the maximum incremental permeability point with a gap much shorter than the optimum air gap.
Abstract: IT HAS LONG been known that when a highly unsymmetrical (I min ≠ I max ) current magnetizes a closed iron core in an inductor or transformer, the optimum design includes an air gap in the core to reduce saturation. The presence of the air gap has two opposing effects: (1) it increases the reluctance of the core to both the biasing (d-c) magnetization and the incremental (a-c) magnetization, and (2) the shift of magnetic operating point due to (1) reduces the reluctance of the iron to the incremental magnetization. If a permanent-magnet slab is used as a counterbiasing means instead of an air gap, the magnetic operating point may be shifted toward the maximum incremental permeability point with a gap much shorter than the optimum air gap. The direct increase in reluctance is then much smaller than in the air-gap case, and the inductance is much larger. A given core size can supply a larger inductance or, conversely, a smaller permanent-magnet-gapped core can supply the same inductance as a larger air-gapped core.
TL;DR: In this article, an equation based on the highest switching surges and including safety factors is developed for the limit of approach to live parts of transmission lines, and the effect of temporary protective gaps is shown.
Abstract: An equation, based on the highest switching surges and including safety factors, is developed for the limit of approach to live parts of transmission lines. The effect of temporary protective gaps is shown, and the mechanism of shocks experienced by linemen during loose contact with a tower is discussed. Such shocks, although harmless, are annoying and can be avoided by the use of conducting shoes Live-line maintenance is performed by many utilities with a high degree of safety at all voltage levels now used. It will be expedient to extend this practice to lines operating at voltages of 460 kv and over, but in so doing it seems advisable to analyze the possible hazards which may be encountered and to see how the present degree of safety can be maintained.
TL;DR: The conductive-sheet analog field plotter as discussed by the authors is a versatile instrument for the study of various types of 2-dimensional field patterns, which can frequently optimize the design of a device without having to fabricate several experimental models.
Abstract: The conductive-sheet analog field plotter is a versatile instrument for the study of various types of 2-dimensional field patterns. By means of a field plotter, one can frequently optimize the design of a device without having to fabricate several experimental models. Thus, a substantial savings in both time and money can be achieved.
TL;DR: An approach to the mechanization of letter sorting called "codesorting" is presented, which utilizes a computer as an integral part of the system and the operational characteristics and requirements of the computer are emphasized.
Abstract: An approach to the mechanization of letter sorting called “codesorting” is presented. This approach utilizes a computer as an integral part of the system. The operational characteristics and requirements of the computer are emphasized.
TL;DR: The second installment in the series on the new epoch in electrical science that such men as Oersted and Volta brought about is presented in this paper, where the authors present the second part of the series.
Abstract: This is the second installment in the series on the new epoch in electrical science that such men as Oersted and Volta brought about.
TL;DR: The 2.19-million-kw Niagara Power Project, now well on its way to completion, will be the largest hydroelectric installation in the Western Hemisphere, if not in the world as mentioned in this paper.
Abstract: The 2.19-million-kw Niagara Power Project, now well on its way to completion, will be the largest hydroelectric installation in the Western Hemisphere, if not in the world. The salient electrical design features of the project are described.
TL;DR: In this paper, the principles of steady-state heat transfer as they apply to the field of electric heating are discussed and the governing differential equations are presented and references containing the solutions for various boundary conditions are cited.
Abstract: THIS PAPER is a discussion of the principles of steady-state heat transfer as they apply to the field of electric heating and, as such, no solutions are derived, but rather the governing differential equations are presented and references containing the solutions for various boundary conditions are cited. In most of the references given, the work was concerned with the temperature distribution in electric coils or other electric apparatus wherein the generation of heat was an unwanted phenomenon and not as is considered here, the prime function of the device. However, since these are the solutions to basic differential equations, they are directly applicable to any other body for which the basic equation and the boundary conditions hold.
TL;DR: The development of the telegraph industry, with its technical problems that were overcome only through fundamental research in electrical phenomena, furnished the greatest impetus to the growth of the profession and the establishment of its professional societies.
Abstract: Electrical engineering as a science dates from the second half of the 19th century. The development of the telegraph industry, with its technical problems that were overcome only through fundamental research in electrical phenomena, furnished the greatest impetus to the growth of the profession and the establishment of its professional societies.
TL;DR: In this article, the influence of all significant design parameters, such as conductor size and depth of the grid below the earth's surface, was considered for the evaluation of switch yards of all practical sizes.
Abstract: Data presented herein make possible the evaluation of grounding resistances of switch yards of all practical sizes. Included is the consideration of the influence of all significant design parameters, such as conductor size and depth of the grid below the earth's surface.
TL;DR: Over-all characteristics and design techniques of on-line data processing systems, used for large-scale operations such as transportation reservations, bank transactions, and inventory control, are described briefly.
Abstract: On-line data processing systems have been developed for industrial and business problems which may be classed as inventory control of products with regional, nation-wide, or even worldwide distribution and demand. The control and reservation of passenger or cargo space in the transportation industry, the handling of deposits and withdrawals in savings banks with many branches, the processing, distributing, and retrieval of information concerning stock transactions and quotations, and the control of inventory for large-scale manufacturing and distributing organizations as well as for government and military organizations are examples of application for which systems of this type are required.
TL;DR: The grounding of supporting structures and enclosures for d-c power circuits and apparatus has been a controversial subject ever since metal-enclosed power rectifiers and switchgear came into use in the electrochemical and other industries as mentioned in this paper.
Abstract: THE GROUNDING of supporting structures and enclosures for d-c power circuits and apparatus has been a controversial subject ever since metal-enclosed power rectifiers and switchgear came into use in the electrochemical and other industries Many users of d-c equipment naturally followed the well-established a-c practice of solidly grounding enclosures through a low-resistance conductor Relatively few of these equipments included sensitive grounding protective relays Many cases of serious injury and damage resulting from ground faults that might have been avoided by the use of grounding protective relays have been described earlier1