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Calculated Temperature of Grid Lateral Wires in Microwave Power TriodesTucker, Jewell 01 September 1976 (has links)
In microwave power triodes the grid drive power causes grid lateral wire heating. This development calculates the temperature of the wire as a function of the drive power, physical dimensions and characteristics of the wire material, for the following boundary conditions:
I. Constant grid drive, grid lateral wire of infinite length not connected to a heat sink.
II. Same as I except the wire is of finite length brazed to a grid frame.
III. The grid excitation in the form of pulses, and the grid lateral wire of finite length brazed to a grid frame.
the equations were verified experimentally by calculating the temperature of a rod whose surface was heated in a vacuum and the temperature measured. The equations were also used to estimate the grid drive power necessary to melt tungsten lateral wire in a microwave power triode, GE18651. The repeated use of LaPlace and Fourier transforms. the Dirac impulse function and convolution integral are the principal mathematical tools used to solve the conduction equations.
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GSM/WCDMA Leakage Detection SystemJohansson, Emil, Myhrman, Kim January 2011 (has links)
Ericsson in Linkoping houses one of the largest test laboratories within thewhole Ericsson Company. Mainly, the laboratories contain equipment forGSM, WCDMA and LTE. To test these systems, a quite large number ofRadio Base Stations are needed. The RBS's are housed in a proportionatelysmall area. Instead of sending signals through the air, cables are used totransfer the RF signals. In this way the equipment communicating witheach other are well speci ed. However this may not be the case if leakageoccur.This thesis work is about developing a system for monitoring the radioenvironment and detect leakages in the test site. There is a need to de newhat a leakage really is and measurements needs to be performed in order toaccomplish this. This report describes how the work has proceeded towardsthe nal implemented solution.
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Applications and characterisation of correlations in quantum opticsKothe, Christian January 2011 (has links)
Quantum optics offers a huge variety of exciting phenomena. Many of them are still in their infancy and especially when it comes to implementing devices using these effects for more than a proof of principle demonstration still many things have to be investigated and understood. In this thesis I discuss the role of correlations in some areas of quantum optics and in some cases compare it to classical optics. Four papers form the core of the thesis. In the first paper, I propose a new measure for entanglement. This measure is based on correlations between two states. I show, how this measure relates to another measure, the concurrence. It turns out that the measure is a bijective map of the concurrence for a pure state of two qubits. I motivate why the new measure is useful if one wants to implement it experimentally. I discuss its behaviour for the case of two qubits and show its properties when dealing with pure and with mixed states. The second paper extends the result of the first one to the case where one has higher-dimensional states than qubits. In the third paper I look at phase super-resolution. I show that it can be interpreted as a purely classical effect and I analyse what is needed and what is not needed to achieve it. Specifically, I show that quantum correlations in terms of entanglement is not needed to demonstrate phase super-resolution. By doing so I propose how one could achieve arbitrarily high phase super-resolution. Finally, the last paper looks at the efficiency of quantum lithography and quantum imaging. It shows, that some basic assumptions in the original proposals of quantum lithography seems unfounded and that, as a consequence, the efficiency is poor. I give formulæ for the explicit scaling behaviour when changing the number of photons in a mode or when changing the number of pixels. The effect of the results on the future of quantum lithography is discussed as well. / Kvantoptiken erbjuder ett stort antal spännande fenomen. Många av dem är fortfarande i sin linda och särskilt när man vill tillämpa kvantoptiska effekter snarare än att bara visa att principen fungerar så finns det många saker och ting som måste förstås och undersökas bättre. I denna avhandling ska jag diskutera vilken roll korrelationer spelar i några områden inom kvantoptik och i några fall ska jag jämföra dem med klassisk optik. Fyra vetenskapliga artiklar bildar kärnan i avhandlingen. I det första pappret föreslår jag ett nytt sammanflätningsmått. Detta mått har sin ursprung i korrelationer mellan två tillstånd. Jag visar hur måttet förhåller sig till ett annat mått, den så kallade "concurrence". Det visar sig att måttet är en bijektiv avbildning av concurrence för rena tillstånd av två qubitar. Jag motiverar varför det nya måttet är användbart när man vill implementera det experimentellt. Jag diskuterar hur måttet beter sig för två qubitar och visar dess egenskaper för rena och blandade tillstånd. Det andra pappret utvidgar första papprets resultat till situationer där man har tillstånd med högre dimension än qubitar. I det tredje pappret undersöker jag superfasupplösning. Jag visar att man kan tolka detta som en rent klassisk effekt och jag undersöker vad man behöver och vad man inte behöver för att uppnå superfasupplösning. Jag visar särskilt att kvantkorrelationer genom sammanflätning inte behövs för att visa superfasupplösning. Därigenom ger jag förslag om hur man kan uppnå godtyckligt hög superfasupplösning. Slutligen tittar jag i sista pappret på effektiviteten av kvantlitografi och kvantavbildning. Pappret visar att några grundläggande antaganden i originalförslaget till kvantlitografi verkar vara illa underbyggda och att därigenom kvantlitografins effektivitet reduceras kraftigt. Jag ger ekvationer för det exakta skalningsbeteendet när man ändrar antalet fotoner i en mod eller när man ändrar antalet pixlar. Jag diskuterar också implikationerna som det medför för kvantlitografins framtid. / QC 20110524
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Mechanical Studies on the Porcine Aortic Valve Part II: A Stress Analysis of the Porcine Aortic Valve Leaflets in DiastoleChong, Ming 12 1900 (has links)
<p> A stress analysis of porcine aortic valve leaflets in diastole at 80 mm. Hg. in-vitro is presented. Incorporations of local surface geometry, leaflet material inhomogeneity, anisotropy and non-linearity are applied. The stress theory used is a modified form of the thin membrane stress theory for a homogeneous, linearly elastic and orthotropic lamina. Modifications are made so that the linear Hooke's Law equations of stress may be applied to the inhomogeneous, non-linearly elastic and orthotropic thin membrane aortic valve leaflets. </p> <p> Stress calculations are made on the premise that the diastolic valve leaflets at 80 mm. Hg. are in pre-transition (that is, characterized by a small elastic modulus) for the circumferential direction, and in post-transition (that is, characterized by a large elastic modulus) for the radial direction. Circumferential stresses are calculated to be relatively negligible; they are estimated to be less than 1 gm/mm². Radial stresses for the non coronary leaflet lie primarily in the 0 to 20 gm/mm² range. The regions of the largest stress concentrations are in the areas of mutual leaflet coaptation, especially near the Nodes of Aranti. A progressive increase of the radial stresses from the sinus annulus edges toward the coaptation edges of the leaflets is also observed. Based on the one valve reported , it appears that the left coronary leaflet is the highest stressed and the right coronary leaflet is the least stressed. Central leaflet radial stresses for the right coronary leaflet are in the 0 to 10 gm/mm² range, as compared to 0 to 20 gm/mm² for the non coronary and left coronary leaflets. </p> <p> The question as to whether the diastolic strains of the valve leaflets are in pre-transition, transition or post-transition is raised. The resolution of the question is seen to be critical to the validity of the stress analysis. It is also realized that further improvements in the analysis are possible through improvements and refinements to the experimental methods used in obtaining the necessary inputs for the analysis. </p> / Thesis / Master of Engineering (ME)
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The Design and Construction of a Surface Analysis Station (Part A)Cuthbert, John Richard 09 1900 (has links)
One of two project reports. Part B is available at http://hdl.handle.net/11375/17552 / <p> The design, construction, and initial operation of a surface analysis station were undertaken. The final UHV system is equipped for ion surface scattering, low energy electron diffraction, Auger analysis, secondary ion mass spectroscopy and residual gas analysis. </p> <p> The main goal of this project was the preliminary operation of the ion surface scattering equipment. A complete beam transport system was constructed utilizing an Einzel lens and electrostatic quadroles. </p> <p> The ion surface scattering was effected through the use of a time-of-flight (TOF) technique to obtain an energy spectrum of particles backscattered from a target surface. The TOF spectrum and subsequent energy spectrum were for 5.1 keV hydrogen ions incident on a practical silver target. </p> / Thesis / Master of Engineering (ME)
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Development of the Signal Detection Electronics for an Auger Spectrometer (Part B)Donnison, William R. 04 1900 (has links)
One of two Project Reports; Part A: http://hdl.handle.net/11375/17663 / No abstract provided / Thesis / Master of Engineering (ME)
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Morse Code Communication Aid for the HandicappedCallway, E.G. 04 1900 (has links)
<p> A microprocessor driven display was built and programmed for the storage and reproduction of Bliss symbols. An explanation is offered for the success of the symbol language in teaching the handicapped. </p> <p> The hardware was designed to be inexpensive enough for classroom use, but still deliver adequate flexibility and resolution. Due to the complexity and variety of the symbols a method of data compaction was developed to reduce the required storage space. </p> <p> Initial tests are presented and suggestions are made for continuing the work. </p> / Thesis / Master of Engineering (ME)
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Natural Gas Micro-Gas Turbine Combustion Flue Gas Characterization and After- Treatment by Non-Thermal Plasma-Catalyst ReactorAmbridge, Scott 10 1900 (has links)
<p>With the increasing need for alternative power sources in the future, the growth of the distributed energy sector will play an important role for meeting future world energy needs. One potential source of distributed energy is the natural gas combustion micro-gas turbine (MGT). Although natural gas is considered a cleaner source of energy than some solid and liquid fuels, there are still significant pollutant emissions. In order to determine the potential pollution from MGTs, two types of MGTs were characterized for their emissions; one single stage moderate lean burn combustion type MGT and one dual stage lean burn combustion type MGT. Furthermore, a novel pollution control device, a trench type nonthermal plasma-catalyst reactor, was examined for potential effectiveness of treating gaseous pollutants in MGT type flue gas.</p> <p>The MGT characterization of the exhaust flue gas revealed that the pollutants of greatest concern for the single stage combustion type MGT were nitrogen oxides (NO<sub>x</sub>) and volatile organic compounds (VOCs), with steady state concentrations of 15ppm (-510 g[NO<sub>x</sub>]/MWh) and 120ppm at a full load of 101.2kW, respectively. VOCs were observed to be higher in the dual stage MGT's flue gas with a maximum steady state concentration of 140ppm at a full load of 70kW. It was observed that the dual stage MGT had a significant amount of particulate matter emission for a diameter smaller than 29nm.</p> <p>Preliminary MGT simulated exhaust gas treatment results for the trench type non-thermal plasma-catalyst reactor were observed to be effective for converting NO to: N0<sub>2</sub>, N<sub>2</sub>, O<sub>2</sub>, CO<sub>2</sub> and H<sub>2</sub>0. Further tests need to be completed on real natural gas combustion exhaust in order to determine the effectiveness of the non-thermal plasma catalyst for treating MGT exhaust.</p> / Master of Applied Science (MASc)
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Part A: Validity of Rutherford Scattering. Part B: A Monte-Carlo Technique for the calculation of keV ion back-scattering from metal surfaces.Agamy, Said January 1973 (has links)
<p>Part A:</p> <p>The purpose of this report is to study the validity of the Rutherford Scattering Law. Both the angular and energy dependence of the . scattering cross-section are checked, also comparison between the absolute cross-section determined experimentally and the theoretical cross-section is made.</p> <p>Here we study the scattering of helium and oxygen ions with energies varying from 0.5 to 2.0 MeV from thin bismuth targets made by implanting 40 keV bismuth ions in low Z(silicon) substrate to doses of 10<sup>16</sup> ions/cm<sup>2</sup>. The implantation process was made on the Isotope Separator and the scattering experiments were made on the Van-de-Graff accelerator of the SSS branch of the AECL. The scattering angles considered here range from 90˚ to 160˚ and a special geometrical arrangement was used to enable us to measure the scattering angle accurately. Also the report contains a brief description of the different sources of errors during target preparation (implantations) and the scattering experiments.</p> <p>Part B:</p> <p>As an introduction to a larger study of ion bombardment phenomena on metal surfaces, we apply the Monte-carlo technique to calculate the range distribution and back-scattering of keV ions from metal surfaces. Lindhard theory is used to calculate both the ion-metal atom scattering and the electron stopping power. The program can be used over a wide range of reduced energies (.1 < ɛ < 30) limited only by the validity of the Lindhard theory. A sample calculation of hydrogen scattering from aluminum is presented.</p> / Master of Engineering (ME)
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Materials Patterning with an Excimer LaserGuzzo, Edward 03 1900 (has links)
An investigation into the feasibility of laser ablation as a material selective removal technique was conducted. Polyimide films approximately 1 micron thick were prepared on silicon wafers. The ablation rate of these films as a function of laser fluence was studied. It was observed that a minimum threshold fluence of 67 +/- 6 mJ/cm^2 had to be surpassed to achieve a significant material removal rate. In addition to polyimide, the removal and damage characteristics of aluminum films were also examined. These films, which ranged in thickness from 50 to 1000 nm, were deposited on polyimide coated silicon wafers. It was found that the best results were produced by a single shot removal technique, with the quality of the hole dependent upon the incident fluence. At lower fluences, removal ceased and only physical damage to the film occurred. In an attempt to characterize this damage, the electrical resistance of small aluminum wires was monitored as they were exposed to laser pulses. It was found that a change in the resistance of the wires could not be detected prior to the onset of visible damage. Once the optimal removal fluences for both materials were determined, a multilayer consisting of an aluminum layer "sandwiched" between two polyimide layers was prepared. By varying only the incident fluence, it was possible to remove upper layers without removing or damaging the underlying ones. In a related experiment, the possible incubation of polyimide by low fluence laser pulses was also examined. / Thesis / Master of Engineering (ME)
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