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  • 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.
51

Control guidelines for the transportation of chemically contaminated dry vacuum pumps

Hildebrandt, Leslie M. January 1998 (has links) (PDF)
Thesis--PlanB (M.S.)--University of Wisconsin--Stout, 1998. / Includes bibliographical references.
52

The transductor amplifier its manner of action and comments on its use for automatic regulation.

Krabbe, Ulrik. Ytterberg, Arle. January 1900 (has links)
Thesis--Danmarks Tekniske Højskole. / Without thesis statement. Summary in Danish. Bibliography: p. 166-167.
53

The transductor amplifier its manner of action and comments on its use for automatic regulation.

Krabbe, Ulrik. Ytterberg, Arle. January 1900 (has links)
Thesis--Danmarks Tekniske Højskole. / Without thesis statement. Summary in Danish. Bibliography: p. 166-167.
54

Analysis of discrete quantum mechanics and Higgs vacuum theories based on concepts involving infinities /

Cheng, Bing-kwan. January 1998 (has links)
Thesis (Ph. D.)--University of Hong Kong, 1999. / Includes bibliographical references.
55

Vacuum flow of gases through channels with circular, annular, and rectangular cross sections

Dong, Walter. January 1956 (has links)
Thesis (Ph.D.)--University of California, Berkeley, 1956. / "Chemistry Distribution" -t.p. Includes bibliographical references (p. 117-118).
56

A study of the generation of vacuum ultraviolet radiation from discharges in helium

Garber, Carl Clifford, January 1976 (has links)
Thesis--Wisconsin. / Vita. Includes bibliographical references (leaves 201-211).
57

The construction of high power vacuum tubes and their uses in radio telephony

Jansky, Cyril Moreau, January 1919 (has links)
Thesis (M.A.)--University of Wisconsin--Madison, 1919. / Typescript. eContent provider-neutral record in process. Description based on print version record.
58

Analise de viabilidade técnica-econômica na substituição de um sistema combinado de geração de vapor-vácuo por bombas secas

Oliva, Robson Vitor [UNESP] 25 January 2013 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:30:11Z (GMT). No. of bitstreams: 0 Previous issue date: 2013-01-25Bitstream added on 2014-06-13T21:00:27Z : No. of bitstreams: 1 oliva_rv_me_guara.pdf: 1375478 bytes, checksum: 3262d22d7d9ad344b00c640163dc65e0 (MD5) / Traditional technologies used to generate vacuum for steelmaking are steam ejectors, liquid ring vacuum pumps and systems combined of them. The steam ejector system has a capacity to generate a medium vacuum 101 kPa (1 atm) a 0,1 Pa (0,01 mbar), the liquid ring pumps only reach 3 kPa (30 mbar) and dried pump cover the range of 101 kPa (1 atm) até 67 Pa (0,67 mbar), band required for use in secondary metallurgy and is the limit of this technology. In this work was realized a case study in the industrial sector that uses the vacuum generation through steam ejectors superheated at 250 ° C and 1,2 MPa (12 kgf/cm2). The vacuum is needed for removal of undesirable gases in the composition of the steel as nitrogen, oxygen, hydrogen and sulfur which causes weakness in the crystalline structure. Currently there have been technological innovations for vacuum generation in applications in VD (vacuum degassing), vacuums until to 67 Pa (0,67 mbar) and VOD (decarburization) for vacuums of 8-20 kPa (80-200 mbar). One of these innovations is mechanical pumps dried formed by three-stage vacuum, joining various technologies, the first and second rotor roots and the third screw rotor. In this study the objective was to measure the real returns offered by the steam ejector system, along with the performance of the boiler compared to the new dry pump technology in steel making industry, will present the advantages, disadvantages and cost effective to replace the vacuum generating system. Representing a 92,7% reduction in energy consumption and 81,4 % reduction in operating costs
59

A hybrid-coupled tunnel-diode amplifier

Holland, John Henry January 1962 (has links)
The analysis and design of a hybrid-coupled tunnel-diode amplifier is described, considering both the hybrid junction and the tunnel-diode circuitry. The fundamental theory of the tunnel diode is reviewed. The hybrid junction is in the form of a strip-line directional coupler which makes use of the inherent contra-directional coupling between two adjacent transmission lines. A complete analysis of the frequency dependence of the response of such a coupler is given. The amplifier is realized using the coupler and a pair of matched diodes terminating mutually isolated ports. To optimize the performance of this type of amplifier the design of the coupler is integrated with the design of the diode circuit. In doing so, account is taken of the frequency dependence of the hybrid junction, an aspect of the problem which has not been treated in the literature. As an example, an amplifier covering the VHF television channels is designed, and experimental results of a working model for a 50-ohm system are presented. The amplifier uses the periodicity of the directional coupler to provide two pass bands spanning Channels 2 to 6 (54 to 88 Mc) and Channels 7 to 12 (174 to 216 Mc), respectively. The two GE lN2939A tunnel diodes used for the amplifier provide a gain of 7.8 db ± 0.3 db for the lower band and 8.9 db ± 0.45 db for the upper band. The maximum input VSWR for the lower and upper bands are less than 2.3 and 3.2, respectively. The theoretical noise figure for a bias current of 0.7 ma is 3.79 db. It is found that the experimental results are in general agreement with the theory. Suggestions for improvement are given in cases where discrepancies do occur. / Applied Science, Faculty of / Electrical and Computer Engineering, Department of / Graduate
60

On the selection of tuning patterns in stagger-tuning multicavity klystron amplifiers

Yuan, John Tsong January 1960 (has links)
In the iterative method for producing maximally-flat response for the multicavity klystron amplifier, a choice must be made in allocating poles to cavities. In this thesis, a method is described for selecting the tuning pattern which will give flat response with maximum gain for a specific multicavity klystron. The iterative method for multicavity klystron amplifiers is extended, to tubes with up to six cavities. It is shown that the optimum tuning pattern has an appreciable advantage in gain over the alternative choices. The practice of allocating the highest-frequency pole to the penultimate cavity is justified, at least for relatively short tubes. Illustrative numerical tuning designs for four-, five- and six-cavity klystron amplifiers with different tuning patterns are given to verify the method. The restrictions of small-signal fundamental-mode theory apply throughout the thesis. / Applied Science, Faculty of / Electrical and Computer Engineering, Department of / Graduate

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