• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 810
  • 523
  • 181
  • 134
  • 126
  • 50
  • 35
  • 35
  • 25
  • 19
  • 16
  • 11
  • 8
  • 8
  • 8
  • Tagged with
  • 2312
  • 408
  • 371
  • 288
  • 275
  • 245
  • 231
  • 217
  • 161
  • 148
  • 144
  • 142
  • 134
  • 133
  • 129
  • 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.
21

Explanation and induction /

Josephson, John R. January 1982 (has links)
No description available.
22

Automatic forward modelling of two-dimensional problems in electromagnetic induction

Poll, Helena Eva 11 July 2018 (has links)
A finite difference algorithm for solving the forward modelling problem of geo-electromagnetic induction in two-dimensional (2D) structures has been developed in this thesis. The governing equations have been modified to solve for the anomalous field by separating out the 'host' field which is assumed to be the field generated by the one-dimensional (1D) conductivity distribution on the left hand side of the model. This was done to prevent the small anomalous fields being masked by the much larger host field due to the finite length of the computer word. One of the most important features of this program is an automatic gridding subroutine which greatly reduces the amount of time required to design a suitable grid for a model and removes the human element from such grid design. Up to 20 periods can be submitted to the model at one time and specific locations (e.g. the locations at which field data are available) can be added to the automatically generated grid. Integral boundary conditions at the surface and bottom (z = d) of the model eliminate the need to extend the grid above the earth's surface or down into the half-space underlying the model. The program has been used to perform a 2D inversion of magnetoteliuric data from a NS profile in Sardinia. The magnetoteliuric responses from two sites along this profile indicated that the structure underneath them could not be considered to be solely 2D. To examine the conductivity anomalies perpendicular to the profile indicated that are affecting the results at these two sites, 2D inversions were performed on the data to obtain their EW conductivity models. The apparent resistivity curves from the models fit the data fairly well at both sites especially at short periods. Many features of the models were in agreement with the 2D model along the profile obtained by Peruzza et al. (1990) and they also provided insight into the geological structure of the area. A study was made of the behaviour of 2D induction arrows over a buried conductivity contrast. Although the general trend of in-phase arrows is to point towards the regions of high electrical conductivity, some investigators have found small amplitude in-phase arrows that point away from these same regions. Reversals such as these, which do not behave according to the general trend, can cause confusion and erroneous interpretation of the in-phase induction arrows. Using a model with two semi-infinite conducting plates, one at the surface and one buried at a depth d in a layered half space, it was found that the period at which a reversal in the in-phase induction arrow direction occurs was a function of the apparent resistivity of the layered host. Anomalous behaviour was found in the short period in-phase arrows from which the coast effect had been removed. The problems in interpretation of such arrows was discussed. Finally a 2D inversion scheme was discussed in which a 2D forward modelling program was incorporated with a minimization routine MTNDEF. First an investigation was made into the relative merits of using the impedances ZTE, ZTM, Zave and Zeff to calculate the ID inversions that are combined to form starting models for the 2D inversions. A subsequent 2D inversion of the North American Central Plains (NACP) anomaly results in a best fit model whose responses show good agreement with the field data from 20 sites. Tests have been performed to ensure that an oversimplification of the starting model is not responsible for the lack of certain features found by other authors. It is concluded that the incorporation of these features in the model is not required in order to obtain a good fit to the field data. / Graduate
23

Optimal design algorithms for induction machines /

Wieczorek, Jan Pawel Unknown Date (has links)
Thesis (PhD)--University of South Australia, 2000
24

The investigation of the small signal inductive effect in P-I-N junction diodes using the equivalent circuit technique of Linvill and Gibbons

Krohn, Norman Fred, January 1963 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1963. / Typescript. Vita. Includes computer source code. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 137-138).
25

A double synchronous speed induction machine

Gifford, Joseph Hugh. January 1948 (has links)
Thesis (M.S.)--University of Wisconsin--Madison, 1948. / Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaf [44]).
26

Modelling deep bar effects in induction machines

Creer, Wallace Hight. January 1984 (has links)
Thesis (M.S.)--University of Wisconsin--Madison, 1984. / Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leav 110).
27

Design of an alternating current squirrel-cage induction motor

Thompson, Thomas Moffett. January 1925 (has links) (PDF)
Thesis (B.S.)--University of Missouri, School of Mines and Metallurgy, 1925. / The entire thesis text is included in file. Typescript. Illustrated by author. Title from title screen of thesis/dissertation PDF file (viewed September 16, 2009) Includes bibliographical references (p. 30) and index (p. 31-32).
28

Inductor simulation utilizing a balanced y-parameter gyrator

Petzold, Donald Wayne, January 1968 (has links)
Thesis (M.S.)--University of Wisconsin--Madison, 1968. / eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.
29

The Effect of Induction experiences on the teaching performance of beggining Secondary School Teachers : The case of Boteti district in Botswana

Pule, G D January 2013 (has links)
The study examined how the induction experiences of beginner secondary school teachers impact on their teaching performance. A total of 15 participants were purposively selected from the four schools. They were four school heads, three senior teachers' staff development and eight teachers who were last to be employed in the four secondary schools in the Boteti District far north of Botswana. The school heads were selected as they are overseers of the schools. The senior teachers' staff development were selected because their job description entail staff development which includes induction and lastly beginner teachers were chosen as they are the ones who are supposed to be inducted. A qualitative case study research design was used whereby data was collected through face-to-face semi structured interviews and open-ended questionnaires. It was fow1d that the maj01ity of beginner teachers who undergo induction training do not perform satisfactorily with regard to delivering to learners; do not fit well in their duties and some even leave the teaching profession at an early stage. The findings indicated that Newly Qualified Teachers are not given enough professional guidance and support. It is recommended that p1incipals as key personnel for induction of Newly Qualified Teachers should welcome Newly Qualified Teachers and assure them of the support and guidance during their initial year of teaching and throughout. Induction programmes should be given more priority and the seriousness they deserve since the first year of teaching is tl1e most important determiner in the teaching career of an individual. / Thesis (M.Ed) North-West University, Mafikeng Campus, 2013
30

Single slot models for cage rotors

Gersh, Danielle January 1995 (has links)
No description available.

Page generated in 0.0892 seconds