Determination of the parameters and parameter variations of a 3-phase induction motor having a current-displacement rotor

1975 ◽  
Vol 122 (9) ◽  
pp. 919 ◽  
Author(s):  
J.E. Brown ◽  
C. Grantham
Keyword(s):  
Induction Motor ◽  
Parameter Variations ◽  
A Current

scholarly journals III. On the atomic weight of manganese

1883 ◽  
Vol 35 (224-226) ◽  
pp. 44-48
Keyword(s):  
Carbon Dioxide ◽  
Silver Chloride ◽  
Atomic Weight ◽  
Special Method ◽  
Its Analysis ◽  
A Current ◽  
Sulphuretted Hydrogen

Our attention has been directed for some time to a new determination of the atomic weight of manganese. This communication gives a succinct account of the results of the preliminary stages of such an inquiry, and although the further progress of the investigation may reveal some errors, still we feel convinced the final numbers can in no way differ materially from the present values, and therefore further delay in publication is unnecessary. The atomic weight of manganese has been determined by many chemists, but the resulting values vary considerably according to the special method selected. The results of the different investigators may be divided into two classes—those giving approximately 55 as the number, and those making it about 54. To the former class belong Turner, Berzelius, and Dumas, all of whom use the same method, viz., the determination of the silver chloride yielded by a weighed amount of chloride of manganese. Turner also made determinations from the analysis of the carbonate, and from the conversion of the monoxide into sulphate. Von Hauer used the same method as that employed by him in the determination of the atomic weight of cadmium, viz., the reduction of manganous sulphate to sulphide by ignition in a current of sulphuretted hydrogen. It is probable that this method is not very trustworthy, as, according to Schneider, the sulphide may be contaminated by oxysulphide. Schneider and Rawack belong to the second class of observers, the former employing the oxalate, and from its analysis calculating the atomic weight by deducting the weight of water and carbon dioxide obtained. Rawack, whose experiments were conducted in Schneider’s laboratory, weighed the water obtained by reducing manganoso-manganic oxide to manganous oxide.

Do centers of origin have a center?

Paleobiology ◽  
1981 ◽  
Vol 7 (3) ◽  
pp. 305-307 ◽  
Author(s):  
John C. Briggs
Keyword(s):  
United States ◽  
North America ◽  
Southeastern United States ◽  
Important Criterion ◽  
Centers Of Origin ◽  
Single Region ◽  
Evolutionary Radiation ◽  
A Current ◽  
Considerable Intensity

A current question being debated with considerable intensity is whether or not certain geographic areas act as centers of evolutionary radiation and supply species to other areas that are less active or less effective in an evolutionary sense. Darwin (1859) was the first to write about centers of origin which he called “single centers of creation.” He argued that each species was first produced within a single region and that it subsequently migrated from that area as far as its powers of migration and subsistence under past and present conditions permitted. Adams (1902), in discussing the influence of the southeastern United States as a center of distribution for the flora and fauna of North America, provided a series of criteria for the determination of “centers of dispersal.” His first, and evidently most important criterion was the location of “the greatest differentiation of a type.”

Study of the residual imperfections using methods of probability theory

2021 ◽  
Vol 87 (9) ◽  
pp. 44-49
Author(s):  
D. A. Kuzmin
Keyword(s):  
Probability Theory ◽  
Generalized Equation ◽  
Structural Elements ◽  
Non Destructive Testing ◽  
Operational Control ◽  
Destructive Testing ◽  
Control Procedures ◽  
Non Destructive ◽  
A Current

Discontinuities in the products that occur during manufacture, mounting or upon operation can be missed during non-destructive testing which do not provide their complete detectability at a current level of the technology. Therefore, it is necessary to take into account that certain structural elements may have discontinuities of significant dimensions. We present the results of using the methods of probability theory in studying the residual imperfections that remains in the structure after non-destructive control and repair of the previously identified defects. We used the results of operational control of units carried out by ultrasonic and radiographic methods. We present a method for determining a multifactorial coefficient that takes into account the detectability of defects, the number of control procedures and the errors in the instrumentation and methodological support, as well as a generalized equation for the probability distribution of detecting discontinuities. The developed approach provides assessing of the level of damage to the studied objects, their classification proceeding from the quantitative data and determination of the values of postulated discontinuities for deterministic calculations. The results obtained can be used to improve the methods of monitoring NPP facilities.

scholarly journals Study of Dual Stator Induction Motor in Photovoltaic-Fuel Cell Hybrid Pumping Application

2020 ◽  
Vol 53 (5) ◽  
pp. 601-608
Author(s):  
Arezki Adjati ◽  
Toufik Rekioua ◽  
Djamila Rekioua ◽  
Abdelmounaim Tounzi
Keyword(s):  
Fuel Cell ◽  
Induction Motor ◽  
Centrifugal Pump ◽  
Cell Hybrid ◽  
Double Star ◽  
Water Requirements ◽  
Matlab Simulink ◽  
Pumping System ◽  
Dynamic Head

This paper discusses the modeling of hybrid Photovoltaic/Fuel cell pumping. This system comprises a photovoltaic generator and a fuel cell, two DC/DC converters, two of inverters which supply a double star induction motor (DSIM) which drives the shaft of a centrifugal pump. The evaluation of the water requirements, the total dynamic head (TDH) and the flow are of great importance to evaluate the various powers allowing the determination of the size of the pumping system. The global proposed system is sized and simulated under Matlab/Simulink Package. The obtained results under different metrological conditions show the effectiveness of the proposed hybrid pumping system.

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