• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 808
  • 523
  • 180
  • 134
  • 126
  • 47
  • 35
  • 35
  • 25
  • 19
  • 16
  • 11
  • 8
  • 8
  • 8
  • Tagged with
  • 2306
  • 404
  • 371
  • 287
  • 278
  • 245
  • 231
  • 217
  • 161
  • 148
  • 144
  • 142
  • 134
  • 133
  • 130
  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.

Quantitative untersuchungen über die Thomsonschen abstossungsversuche ...

Winderlich, Alfred Theodor, January 1905 (has links)
Inaug.-diss.--Greifswald. / Lebenslauf.

Determination of conductor clearances-to-ground for EHV AC and DC transmission lines

Stremlaw, Arthur John January 1968 (has links)
The analyses presented in this thesis are based on a consideration of induction effects below transmission lines and the hazards as presented to the public. The rapid increase of transmission voltages has caused a great deal of concern among utilities about these hazards. The induction effects are a function of line height and at present there is conflict concerning-these dimensions. Primarily, this thesis is concerned with the establishment of the minimum line-to-ground clearances of EHV ac and dc transmission lines. These clearances are established in terms of the electric field under the line based on the "electric field recognition level". Equations are derived for the electric field, and potential at any point below the line in Chapter 2. These equations are then used in Chapter 3 to show the effect of conductor spacing, height and size on the field. Also, the effect of sky wires and bundle conductors is noted. Chapter 4 derives an allowable value of electric field which is used in Chapter 5 to derive the required heights. Chapter 6 considers a reduction of these clearances or induction effects using ground wires below the line conductors for shielding purposes. Experimental readings are obtained in Chapter 7 to verify the equations derived in Chapter 2 and the effects of sky wires and bundle conductors on the electric field below the line. Chapter 8 establishes right-of-way widths based on induction effects. / Applied Science, Faculty of / Electrical and Computer Engineering, Department of / Graduate

'n Ondersoek na die elektromagnetiese verbetering van die induksiesmelting van metale

Dorland, Pieter 29 May 2014 (has links)
M.Ing. (Electrical And Electronic Engineering) / The metals manufacturing industry is the link between the mining industry, where the ore is mined, and the manufacturing industries, where metals are utilized to create a wide range of products. Melting processes.are used in the manufacturing of metals from the ore, of which induction melting is one of the possible melting processes. In this study the improvement of induction melting of metals is investigated. A new topology for an induction melting furnace is proposed, and this topology is thoroughly investigated. The induction melting process is influenced by certain user-controlled variables as well as the electromagnetic layout of the furnace. In this study, the influence of these variables on the performance of the furnace are investigated through finite element simulations and insight is also gained into the influence of the electromagnetic layout of the system. An experimental induction melting furnace is described in this study, investigated and compared to the predictions from the simulations. Improvements from structural, thermal and measuring viewpoints are also investigated and implemented.

Novice teachers' perceptions of their first year induction program in urban schools

Charleston-Cormier, Phyllis A 02 June 2009 (has links)
The study examined and evaluated perceptions of first year teachers on the effectiveness of induction activities, assistance, and support following participation in their induction program. This was a quantitative study of novice teachers in an urban school district. Teachers from all teaching disciplines, both at the elementary and secondary level, participated in the study. The researcher used the Novice Teacher Perceptions Assessment to survey 171 teachers. Of the 171 surveys distributed, 144 were returned and analyzed for this study. From the survey data, descriptive statistics and frequency counts were obtained for demographic information items and specific induction activities, assistance, and support. All data were analyzed for the effectiveness of teacher induction program components. The results of this study revealed that novice teachers were provided with six factors that were important to them. The factors were: information concerning the school and its culture; support for emotional stress; assistance in instructional strategies; the allocation of resources; and overall support of the induction program in relation to mentors and reflection. Perceptions were consistent among the demographics; namely, the subject taught, grade level taught, gender, age, ethnicity and environment. Novice teachers ranked ten activities they valued while in the induction program. The activities most valued were the support they received in assistance with discipline problems; feedback from observations, and the opportunity to observe other teachers. On the contrary, novice teachers least valued the support given to them relating to the physical aspect of their classrooms. This included classroom arrangement, designing bulletin boards and learning centers.

Determination of a simplified method for evaluating earth resistivity for inductive coordination calculations

Polk, Orval Harold, 1904- January 1933 (has links)
No description available.

Analysis of concepts of weak confirmation

Wiebe, Phillip Howard January 1972 (has links)
ix, 297 leaves ; 26 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (Ph.D.)--University of Adelaide, Dept. of Philosophy, 1972

Analysis of concepts of weak confirmation.

Wiebe, Phillip Howard. January 1972 (has links) (PDF)
Thesis (Ph.D.) -- University of Adelaide, Dept. of Philosophy, 1972.

A solid state controller for induction loads /

Havas, George. January 1972 (has links)
Thesis (M.S.)--Youngstown State University, 1972. / Typescript. Includes bibliographical references (leaf 85).

Relations between length, elasticity, and magnetization of iron and nickel wires

Gallaudet, Edson Fessenden, January 1896 (has links)
Thesis (Ph. D.)--Johns Hopkins University. / Biographical sketch. Bibliography: p. 29.

The effect of pressure upon magnetic permeability ...

Frisbie, Fannie Cornelia. January 1904 (has links)
Thesis (Ph. D.)--University of Chicago. / "Reprinted from the Physical review, vol. XVIII, no. 6, June, 1904."

Page generated in 0.0992 seconds