Rozprawy doktorskie: „Electronic measurements”

1

Van, Rooyen M. W. (Melchior Werner). "Simple broadband measurements of balanced loads using a network analyzer". Thesis, Stellenbosch : Stellenbosch University, 2001. http://hdl.handle.net/10019.1/52451.

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Thesis (MEng)--University of Stellenbosch, 2001.
ENGLISH ABSTRACT: Balanced loads such as antennas normally require baluns when they are measured. For wide band applications, designing and building a balun complicates the measurement and introduces errors. A simple model for load impedances was developed, together with a novel measurement procedure. The procedure enables the measurement of balanced loads using a network analyzer with no balun. Measured and simulated results are presented.
AFRIKAANSE OPSOMMING: Gebalanseerde laste soos antennas benodig gewoonlik balons om korrek gemeet te word. Die ontwerp van 'n balon vir wye band toepassings bemoeilik die metings en veroorsaak foute. 'n Eenvoudige model vir die lasimpedansies is ontwikkel sowel as 'n eenvoudige meetmetode. Die metode word gebruik om die gebalanseerde laste te meet met 'n netwerk analiseerder sonder die gebruik van 'n balon. Gemete en gesimuleerde resultate word getoon.

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Grebing, Jochen [Verfasser]. "Electronic Transport Measurements on Si4 Clusters / Jochen Grebing". Aachen : Shaker, 2010. http://d-nb.info/1081885424/34.

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Damaraju, Sarita. "Performance measurements of Web services". Morgantown, W. Va. : [West Virginia University Libraries], 2006. https://eidr.wvu.edu/etd/documentdata.eTD?documentid=4581.

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Thesis (M.S.)--West Virginia University, 2006.
Title from document title page. Document formatted into pages; contains v, 42 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 32-34).

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Hutchens, Chris. "An integrated design strategy for a range of industrial electronic pressure instrumentation". Thesis, University of South Wales, 1999. https://pure.southwales.ac.uk/en/studentthesis/an-integrated-design-strategy-for-a-range-of-industrial-electronic-pressure-instrumentation(604926cd-cf70-4281-afea-f64b05ab8161).html.

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This portfolio details the design, construction and testing of three high accuracy digital pressure indicators. A discussion of old and contemporary pressure measurement technologies is included, as well as a comprehensive market survey of electronic pressure measurement instruments currently available. An integrated design strategy is adopted for the three separate digital pressure instruments, namely a battery - powered stand alone unit, a retransmitting version and an intrinsically safe version of the battery powered unit. Their implementation takes into account many design issues including ease of manufacturing, low power circuit design and electromagnetic compatibility. Novel features available upon all three instruments resulting from the design strategy adopted are high accuracy measurements, typically ±0.2% of full scale, a battery life of over 12 months, push button zeroing and linearisation, electromagnetic compliance with minimum design changes and an intrinsically safe power supply design that may be used not only in the instrument for which it was designed but for future instruments. Individual design issues with respect to each instrument are in the three project sections which complete this portfolio.

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5

Hall, Angus John. "Electronic measurements of area and perimeter in ultrasonic images". Thesis, University of Leeds, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.328883.

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Lu, Shi-Jian. "The significance of atmospheric effects in electronic distance measurement". Thesis, University of Leeds, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.278369.

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Nussbaum, Nicholas J. "In-plume measurements of combustion exhaust /". abstract and full text PDF (free order & download UNR users only), 2007. http://0-gateway.proquest.com.innopac.library.unr.edu/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:1447810.

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Thesis (M.S.)--University of Nevada, Reno, 2007.
"May, 2007." Includes bibliographical references. Online version available on the World Wide Web. Library also has microfilm. Ann Arbor, Mich. : ProQuest Information and Learning Company, [2007]. 1 microfilm reel ; 35 mm.

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Crockett, Dean D. "Direct measurement of parallel plate heat sink bypass flow". Online access for everyone, 2006. http://www.dissertations.wsu.edu/Thesis/Fall2006/d_crockett_121206.pdf.

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Prabhakaran, Pradeep. "Development of electronic instrument for defect measurements with eddy currents /". St. Lucia, Qld, 2004. http://www.library.uq.edu.au/pdfserve.php?image=thesisabs/absthe17873.pdf.

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Sjödahl, Mikael. "An electronic speckle photography system for in plane deformation measurements". Licentiate thesis, Luleå tekniska universitet, Strömningslära och experimentell mekanik, 1993. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-16973.

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Cavusoglu, Mehmet Cagdas. "Improvements in electronic speckle pattern interferometry for residual stress measurements". Thesis, University of British Columbia, 2007. http://hdl.handle.net/2429/31579.

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Electronic Speckle Pattern Interferometry (ESPI) is an optical technique used for measuring surface displacements in the order of a wavelength of light by comparing interference patterns taken before and after surface deformation. Residual stress measurement is one of the applications where ESPI is useful. The technique is attractive because it provides very detailed information on deformation field and low per-measurement cost. However, ESPI data possess high noise content due to its high sensitivity to disturbances. In this research, factors that affect the quality of ESPI data were studied. The most important ones were found to be the specimen surface quality, illumination level and speckle size. The image quality was greatly improved by surface preparation. Good and faulty data were separated by evaluating their modulation level and identifying the saturated pixels. Mathematical methods were proposed to improve the data quality by either replacing the faulty data with good data or smoothing the data by filtering. Two common-path arrangements with single and double mirrors, which provide in-plane sensitive measurements, were designed to eliminate the separate and delicate optical paths. They improved the stability of ESPI measurements and greatly reduced the pixel drift that was a problem in the existing arrangement. The double mirror arrangement provided the measurement of full stress field. The single mirror method was confirmed by stress measurement, whereas the double mirror method could not be validated due to low data quality. Recommendations were made for an enhanced future design of this method.
Applied Science, Faculty of
Mechanical Engineering, Department of
Graduate

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O'Connell, Michael Patrick. "Electrical impedance measurements of the uterine cervix in pregnancy". Thesis, University of Hull, 2002. http://hydra.hull.ac.uk/resources/hull:8032.

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This is the first time that electrical impedance studies have been performed on the pregnant cervix. In this thesis the following has been demonstrated: 1. An inter-observer variability in resistivity readings, initially of the order of 20%, but decreasing to 1% once proficiency with the technique was established. 2. An intra-observer variability in resistivity readings of less than 15% in 94% of cases using the 5.5mm probe and 90% when using the 8mm probe. 3. A degree of heterogeneity in the pregnant cervix as attested to by the differences in resistivity measurements on different sites on the cervix. Some of these changes were partly due to technical difficulties. Nevertheless there appeared to be an increase in extracellular resistivity measurements between the anterior and posterior lips of the external cervical os. 4. A positive correlation between the resistivity measurements and gestational age using the 5.5mm probe. No significant correlations were identified between resistivity readings and both parity and maternal age. 5. A statistically significant difference in resistivity readings when comparing the non-pregnant and pregnant cervix. The change in readings was in a direction which reflected the increase in tissue hydration described by others. 6. A statistically significant difference between readings for ripe and unripe cervices at the time of induction of labour, with a fall in extracellular resistivity with increasing favourability as assessed by the Bishop score. This was accompanied by an increase in intracellular resistivity with increasing cervical favourability. The effect of prostaglandin administration on the pregnant cervix demonstrated a decrease in extracellular resistivity and an increase in intracellular resistivity associated with the cervical ripening process. Whilst the results were neither of statistical nor of clinical significance, they were nevertheless in the direction predicted. 7. A statistically significant correlation between extracellular resistivity and interval to delivery using the 8mm probe. 8. A new investigative modality that had high patient acceptability. To date the findings demonstrated in this thesis conceptually agree with the literature on the pregnant cervix. Thus it is imperative to continue with further studies of this new investigative modality.

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Ernsting, David. "Electron momentum density studies of the electronic structure of complex systems : measurements and ab initio calculations". Thesis, University of Bristol, 2015. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.687439.

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A method for computing electron momentum densities and Compton profiles from ab initio calculations is presented. This is employed, together with the momentum density spectroscopy known as Compton scattering to investigate the electronic structure of MgCNi3. A method for computing the positron state within a material is also presented. In our method for computing the electron momentum density, reciprocal space is divided into optimally-shaped tetrahedra for interpolation, and the linear tetrahedron method is used to obtain the momentum density and its projections such as Compton profiles. Results are presented and evaluated against experimental data, showing good agreement, and demonstrating the accuracy of our method. For the intermetallic superconductor MgCNi3 , high-resolution x-ray Compton scattering experiments were combined with electronic structure calculations to study a sample with the composition MgCO.93 Ni2.85. Our calculations indicate that the electronic structure, whilst smeared by disorder, does not drastically change in the presence of vacancies, and provide an explanation for some of the discrepancies between measurements of single crystals and polycrystals. Compton scattering measurements were used to determine a Fermi surface in good agreement with that of our supercell calculation, establishing the presence of the hole and electron Fermi surface sheets that are necessary for the proposed two-gap model for the superconductivity. We identify significant smearing of certain parts of the Fermi surface when C and Ni vacancies are present. To calculate the positron state, we have implemented two component density functional theory in the limit of vanishing positron density. We present calculations of the positron lifetime, affinity, and of the momentum density of annihilating electron-positron pairs, for several materials, using a wide variety of electron-positron correlation and enhancement schemes, finding excellent agreement with previous calculations and experimental results. Possible limitations of the method are found in describing positrons localised in vacancies .

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14

Datla, Venu. "Measurements based performance analysis of Web services". Morgantown, W. Va. : [West Virginia University Libraries], 2005. https://eidr.wvu.edu/etd/documentdata.eTD?documentid=4158.

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Thesis (M.S.)--West Virginia University, 2005.
Title from document title page. Document formatted into pages; contains v, 47 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 37-41).

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15

Forsberg, Erik. "Electronic and Photonic Quantum Devices". Doctoral thesis, KTH, Microelectronics and Information Technology, IMIT, 2003. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-3476.

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In this thesis various subjects at the crossroads of quantummechanics and device physics are treated, spanning from afundamental study on quantum measurements to fabricationtechniques of controlling gates for nanoelectroniccomponents.

Electron waveguide components, i.e. electronic componentswith a size such that the wave nature of the electron dominatesthe device characteristics, are treated both experimentally andtheoretically. On the experimental side, evidence of partialballistic transport at room-temperature has been found anddevices controlled by in-plane Pt/GaAs gates have beenfabricated exhibiting an order of magnitude improvedgate-efficiency as compared to an earlier gate-technology. Onthe theoretical side, a novel numerical method forself-consistent simulations of electron waveguide devices hasbeen developed. The method is unique as it incorporates anenergy resolved charge density calculation allowing for e.g.calculations of electron waveguide devices to which a finitebias is applied. The method has then been used in discussionson the influence of space-charge on gate-control of electronwaveguide Y-branch switches.

Electron waveguides were also used in a proposal for a novelscheme of carrierinjection in low-dimensional semiconductorlasers, a scheme which altogether by- passes the problem ofslow carrier relaxation in suchstructures. By studying aquantum mechanical two-level system serving as a model forelectroabsorption modulators, the ultimate limits of possiblemodulation rates of such modulators have been assessed andfound to largely be determined by the adiabatic response of thesystem. The possibility of using a microwave field to controlRabi oscillations in two-level systems such that a large numberof states can be engineered has also been explored.

A more fundamental study on quantum mechanical measurementshas been done, in which the transition from a classical to aquantum "interaction free" measurement was studied, making aconnection with quantum non-demolition measurements.

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16

Fiebig, Matthias. "Spatially resolved electronic and optoelectronic measurements of pentacene thin film transistors". Diss., lmu, 2010. http://nbn-resolving.de/urn:nbn:de:bvb:19-122033.

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Bertrand, Fabienne. "Fluvial erosion measurements of streambank using Photo-Electronic Erosion Pins (PEEP)". Thesis, University of Iowa, 2010. https://ir.uiowa.edu/etd/642.

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Fluvial erosion incites significant bridge scour and large-scale bank erosion causing estimated $1.1 billion damage in the Midwest. Conventional, manual, field monitoring methods, typically erosion pins, cross-section resurveys or terrestrial photogrammetry, used to monitor fluvial erosion rates merely provide a net change in bank surface retreat since the previous measurement. If mass wasting has occurred, the ongoing fluvial erosion would be masked. Erosion event timing, and the precise bank response to individual flow or flow hydrograph changes, is generally uncertain. Thus, a technique that automatically quantifies bank erosion on a continuous basis is needed. This study will monitor the bank response to individual flow (i.e., fluvial erosion) using the Photo-Electronic Erosion Pin (PEEP) sensors in Clear Creek Iowa. It attends to monitor a full episode of bank change, including event timings and magnitude information for specific erosion and deposition events, which can be compared to flow discharges and hydrographs. If exploited, this method can lead to more detailed analysis of bank erosion related to temporal fluctuations in the suspected hydraulic forces.

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18

Akambi, Aboudou S. "Low cost test fixture for self-resonant frequency measurements of passive chip components". abstract and full text PDF (free order & download UNR users only), 2005. http://0-gateway.proquest.com.innopac.library.unr.edu/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:3209953.

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Sahara, Emmy. "Stripping potentiometric determination of trace metals in environmental materials /". View thesis, 1996. http://library.uws.edu.au/adt-NUWS/public/adt-NUWS20030822.171402/index.html.

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French, Roger Harquail. "Electronic structure of A12O3 : VUV reflectivity measurements from room temperature to 1100C̊". Thesis, Massachusetts Institute of Technology, 1985. http://hdl.handle.net/1721.1/86250.

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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Materials Science and Engineering, 1985.
MICROFICHE COPY AVAILABLE IN ARCHIVES AND SCIENCE.
Includes bibliographical references.
by Roger Harquail French.
Ph.D.

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21

Sjödahl, Mikael. "Electronic speckle photography applied to in-plane deformation and strain field measurements". Doctoral thesis, Luleå tekniska universitet, Strömningslära och experimentell mekanik, 1995. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-17150.

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Non-contacting measurements of deformation and strain fields are of great importance in experimental mechanics. This thesis describes the development and applications of a video-based, computerized system called electronic speckle photography that measures the in-plane deformation of a strained body. The physical restrictions that limits the performance of the system have been carefully analysed. The system determines the deformation of a characteristic pattern, somehow attached onto the object surface. A FFT based cross-correlation of subimages from the two object states of interest is calculated. Subpixel accuracy is obtained through a Fourier serie expansion of the discrete correlation surface. For a pattern to be considered characteristic it has to be completely random, be of a high contrast and high frequent enough so that a small portion of the digitized image gets typical for its position. A good example of a characteristic pattern is a laser speckle pattern, but any pattern that fulfills the requirements can be used. For a good correlated pattern the system manages to calculate each displacement vector in the field with an accuracy of 1 % of a pixel. The accuracy decreases with increased speckle size and increased speckle decorrelation. An application in which the ESP-system has succesfully been used is to measure the deformation field caused by hygroexpansion in paper. Of primary interest in experimental mechanics is the strain field. There are two possibilities to determine the in-plane strain field with the use of the ESP-system. The first is to differentiate the measured deformation field obtained using either a laser speckle pattern or a white light speckle pattern. For this to be a feasable alternative the random error in the deformation field has to be decreased even further through the use of some filter. It seems difficult to obtain better accuracies than 100 μ strain in the strain fields through the differentiation process without losses in the spatial resolution. The second possibility relies on the motion of defocused laser speckle patterns. By combining the measured deformation fields obtained from four different illumination directions, all components of the in-plane strain field can be determined with an accuracy comparable to that of an electrical strain gauge (10 μ strain with retained spatial information. In measurements using laser speckle patterns to produce reliable results, a careful analysis of the behaviour of these patterns concerning speckle displacement, decorrelation and image point-object point correspondence have to be made. A telecentric imaging system has many positive qualities concerning these parameters for use in a defocused system and is the one that has been used in the measurements.
Godkänd; 1995; 20070426 (ysko)

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Sahara, Emmy. "Stripping potentiometric determination of trace metals in environmental materials". Thesis, View thesis, 1996. http://handle.uws.edu.au:8081/1959.7/29143.

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This thesis describes the development and application of stripping potentiometric methods for reliable determination of some trace metals in natural waters on a glassy carbon mercury film electrode (GCMFE). The development of these methods involved investigation of factors influencing the stripping potentiometric measurement, such as selection of adequate supporting electrolyte, choice of pH and/or concentration of supporting electrolyte, oxidant concentration, deposition potential, deposition time, stirring or sample rotation rate and equilibrium period. Moreover, the influence of complexing agents and the magnitude of constant current were carefully investigated for adsorptive cathodic stripping potentiometric methods. In addition, linear concentration range and detection limits were considered. The analytical application of the method to some natural waters was also demonstrated. It is concluded that the stripping potentiometric methods developed in this study are adequate for ultra-trace determination of copper, lead, cadmium, zinc, nickel and molybdenum. The methods provide very simple procedures, excellent precision and accuracy for the reliable determination of the six metals in natural water samples.

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23

Wagner, James Michael. "A hybrid finite element analysis of shot peen contour forming using residual stress measurements". Thesis, Wichita State University, 2013. http://hdl.handle.net/10057/7049.

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In order to develop surfaces that have the proper curvature for aerospace structures, it is sometimes necessary to use shot peen forming, also known as contour forming, to create the desired shape in a piece of metal. Since the preferred metal in aerospace continues to be aluminum and its alloys, this study will concentrate on the effects of shot peening on aluminum. Typically, shot intensity is measured using standard Almen strips made from cold rolled SAE 1070 spring steel. Since the effects of the shot on aluminum is the chief concern of this study, aluminum strips of the same size and thickness will be used to determine the intensity of the shot on aluminum parts. These strips will be exposed for different amounts of time to different intensities, measured using the steel Almen strips, and then the intensity (or arc height) will be measured on the aluminum strips. The residual stresses in these strips will then be measured using the hole drill method (ASTM E837). The stresses from the residual stress test will then be used to develop a finite element model that simulates the aluminum strips and the deformation in them. The model will then be calibrated with the empirical data. From there, it will be the goal of this study to be able to predict the deformation of aluminum parts when exposed to certain shot peen intensities. This will enable more efficient contour forming processes with less rework. Furthermore, the trial and error of a manual process can be avoided with the use of robotics. Robotics/Automation can also help in creating more consistent results.
Thesis (M.S.)--Wichita State University, College of Engineering, Dept. of Mechanical Engineering.

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Shaver, Mark D. "Wideband energy reflectance measurements: normative study and effects of negative and compensated middle ear pressures". Diss., Wichita State University, 2010. http://hdl.handle.net/10057/3657.

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Conventional clinical procedures for middle ear assessment have been used for several decades but have shown limitations. Application of a new technology, wideband energy reflectance (ER), has shown great potential. The ER measurement determines the proportion of acoustic energy reflected by the middle ear, across a broad frequency range. Negative middle ear pressure (MEP) is a highly prevalent, and mostly transient, form of middle ear dysfunction which effects ER measurement. Goals of the present study were to examine various factors relating to the ER test: (1) test-retest reliability, (2) the effects of pressure manipulations, (3) the effects of negative MEP, and (4) the effectiveness of a corresponding compensation procedure. Data were collected in 48 adults and analyzed across the frequency range from 0.223 to 8 kHz. Measurements were conducted using both ambient and dynamic pressure methods, under three conditions: normal MEP, negative MEP, and compensated negative MEP. Correlation between immediately repeated tests were strong for all frequencies. The sweeping pressure procedure caused ER reduction for a few frequencies but differences were small. Thirty-five subjects were able to produce a negative MEP ranging from -40 to -220 daPa. Negative MEP increased ER at low- and mid-frequencies while decreasing ER at high-frequencies. Magnitude of changes and frequency at which maximum change occurred increased when MEP became more negative. Compensated negative MEP reduced ER at low- and mid-frequencies but increased ER at high- frequencies. The present study demonstrated that negative MEP altered ER in a frequency-specific pattern. The compensation procedure eliminated the effects of negative MEP. Immediate test-retest reliability of the ambient ER test was excellent. Both probe reinsertion and manipulation of the ear canal and middle ear pressure produced minimal effects.
Thesis (Ph.D.)--Wichita State University, College of Health Professions, Dept. of Communication Sciences and Disorders

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Rivord, Jeremy. "Modeling contaminant spills on the upper Truckee River in CA and NV". abstract and full text PDF (UNR users only), 2008. http://0-gateway.proquest.com.innopac.library.unr.edu/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:1456401.

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Grönström, Niclas. "Optimal Demagnetization of Transformer After Winding Resistance Measurements". Thesis, KTH, Skolan för elektroteknik och datavetenskap (EECS), 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-291560.

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In this thesis, transformer demagnetization in connection to winding resistance tests is investigated. In transformer testing, winding resistance measurement (WRM) is an important test used to detect winding or connection faults. It is common practice to measure the resistance by injecting a DC current into the windings of a transformer. The method magnetizes the core, which leads to the transformer core remaining magnetized even after the test. A magnetized core can cause various problems, such as inrush currents that are several times higher than the rated current. Furthermore, residual magnetism may influence other AC diagnostic tests, such as the SFRA (Sweep Frequency Response Analysis) test and the excitation current test. Therefore, it is recommended to demagnetize transformers after WRM. The core-type and winding configuration may impact the demagnetization process. This makes the different demagnetization approaches of interest, so that the most efficient method can be used. This thesis presents demagnetization experiments on several power transformers with different core-types and winding configurations. The transformers were magnetized with WRM and then a TRAX (transformer and substation test system) was used to demagnetize the transformers with different approaches. Numerous measurements were performed on a three-limb and a five-limb power transformer. The effectiveness of the demagnetization methods was measured by using the excitation current in magnetized and demagnetized state as a comparative tool. It is shown that the demagnetization approach for the three-limb core had little impact on the magnetization result. The excitation currents at demagnetized state for the different combinations was roughly equal. The five-limb transformer was demagnetized on the middle limb, and then demagnetized on the outer limbs to see if the demagnetization gave better results. For the five-limb transformer, the measurements showed that the demagnetization approach impacted the results. Different Yy configurations were tested, and the result showed that the remanence was removed after one demagnetization with a phase to phase approach. However, if a Yy configuration was demagnetized with phase to neutral, then the transformer had to be demagnetized twice to remove the remanence. The result for the Yd configuration showed that it was not improved by a phase to phase approach. The phase that was magnetized did in general have a slightly larger excitation current than the other phases, even after demagnetization.
I detta examensarbete undersöks avmagnetisering av transformatorer i samband med lindningsresistansprovning. Vid transformatorprovning är mätning av lindningsresistans ett viktigt test som används för att upptäcka lindningseller kopplingsfel. Vanligtvis mäts resistansen genom att en likström injiceras i transformatorns lindningar. Processen magnetiserar kärnan, vilket leder till att transformatorn förblir magnetiserad även efter testet. En magnetiserad transformator kan orsaka olika problem med diagnostiska tester och leda till inkopplingsströmmar som är flera gånger högre än märkströmmen. Vidare kan restmagnetism påverka AC-tester, såsom SFRA-testet (Sweep Frequency Response Analysis) och exciteringsströmstestet. Därför rekommenderas det att transformatorer avmagnetiseras efter lindningsresistanstest. Kärntyp och lindningskonfiguration kan ha påverkan på avmagnetiseringsprocessen. Det gör det intressant att undersöka olika avmagnetiseringsmetoder, så att den mest effektiva metoden kan användas. Detta arbete demonstrerar avmagnetiseringsexperiment på flera krafttransformatorer med olika kärntyper och lindningskonfigurationer. Transformatorerna magnetiserades genom lindningsresistansmätning och sedan användes en TRAX (transformer and substation test system) för att avmagnetisera transformatorerna med olika tillvägagångssätt. Flera mätningar utfördes på trebenta och fembenta krafttransformatorer. Avmagnetiseringsmetodernas effektivitet mättes genom att jämföra exciteringsströmmen i magnetiserat och avmagnetiserat tillstånd. Det visas att avmagnetiseringsmetoden för den trebenta kärnan hade liten inverkan på magnetiseringsresultatet. Exciteringsströmmarna vid avmagnetiserat tillstånd för de olika kombinationerna var ungefär lika. Den fembenta transformatorn avmagnetiserades först på mittbenet och sedan på de yttre benen för att se om resultaten förbättrades. För den fembenta transformatorn visade mätningarna att avmagnetiseringsmetoden påverkade resultaten. Olika Yy-konfigurationer testades och resultatet visade att remanensen avlägsnades efter den första avmagnetiseringen med fas till fas tillvägagångssättet. Men om Yy-konfigurationen avmagnetiserades med fas till neutral, då krävdes det att transformatorn avmagnetiseras två gånger för att få bort remanensen. Resultatet för Yd-konfigurationen visade ingen förbättring genom fas till fas tillvägagångssättet. Den fas som magnetiserades hade i allmänhet en något större exciteringsström än övriga faser, även efter avmagnetisering.

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Dukkipati, Ravi Kiran. "Experimental investigation of fiber sizing-test fluid interaction for in-plane permeability measurements of continuous fibers". Thesis, Wichita State University, 2007. http://hdl.handle.net/10057/1534.

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Many manufacturers are using liquid composite molding (LCM) to manufacture composites because of its simplicity and cost effectiveness. This generic process includes techniques such as vacuum assisted resin transfer molding (VARTM), resin transfer molding (RTM), and Seemann composite reaction infusion molding (SCRIM). VARTM is most commonly used due to its low tooling cost and ease of use. One of the most important factors that affect the manufacturability of composite parts is permeability. Permeability usually affects resin flow within fibers; hence, many researchers have placed importance on the measurement of this factor in various studies. Alternate test fluids such as corn syrup, silicon oil and motor oil are being used to calculate permeability, since they are cheaper, easy to clean, and are not volatile like resins. Permeability is generally affected by fiber sizing-test fluid interaction, fiber volume fraction, and fiber orientation. In the present study, permeability effects due to fiber chemical coating or sizing were investigated using VARTM. Experiments were conducted by inducing high- and low-viscosity corn syrup and silicon oil through uni-directional glass fibers, bi-axial glass fibers, and two types of uni-directional carbon fibers, with and without sizing. Darcy’s law was used to calculate permeability. Significant permeability differences found using fibers with and without sizing are reported. Separate saturated flow rate measurements for one of the uni-directional carbon fibers and uni-directional glass fibers, both sized and unsized, were carried out by infusing corn syrup and silicon oil with similar viscosities. It was found that, over time, corn syrup displayed a gradual decrease in flow rate for saturated fiber material for constant vacuum infusion. From previous research studies, the flow rate history in the RTM process showed two stages: initial rapid flow and steady-state flow. However, in the VARTM process, the cumulative mass vs. time plot was linear. The corresponding flow rate vs. time plot showed a high initial flow rate but was decreased with time when corn syrup was used for both uni-directional glass and carbon fibers, with and without sizing. This effect was not observed in the case of silicon oil. It was concluded that corn syrup should be used with caution as a test fluid for permeability measurements until further investigations can be made.
Thesis (M.S.)--Wichita State University, College of Engineering, Dept. of Mechanical Engineering
"December 2007."

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Dukkipati, Ravi Kiran Soschinske Kurt A. "Experimental investigation of fiber sizing-test fluid interaction for in-plane permeability measurements of continuous fibers /". Thesis, A link to full text of this thesis in SOAR, 2007. http://hdl.handle.net/10057/1534.

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Simpson, Charles Robert Jr. "Analysis of Passive End-to-End Network Performance Measurements". Diss., Georgia Institute of Technology, 2007. http://hdl.handle.net/1853/14612.

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NETI@home, a distributed network measurement infrastructure to collect passive end-to-end network measurements from Internet end-hosts was developed and discussed. The data collected by this infrastructure, as well as other datasets, were used to conduct studies on the behavior of the network and network users as well as the security issues affecting the Internet. A flow-based comparison of honeynet traffic, representing malicious traffic, and NETI@home traffic, representing typical end-user traffic, was conducted. This comparison showed that a large portion of flows in both datasets were failed and potentially malicious connection attempts. We additionally found that worm activity can linger for more than a year after the initial release date. Malicious traffic was also found to originate from across the allocated IP address space. Other security-related observations made include the suspicious use of ICMP packets and attacks on our own NETI@home server. Utilizing observed TTL values, studies were also conducted into the distance of Internet routes and the frequency with which they vary. The frequency and use of network address translation and the private IP address space were also discussed. Various protocol options and flags were analyzed to determine their adoption and use by the Internet community. Network-independent empirical models of end-user network traffic were derived for use in simulation. Two such models were created. The first modeled traffic for a specific TCP or UDP port and the second modeled all TCP or UDP traffic for an end-user. These models were implemented and used in GTNetS. Further anonymization of the dataset and the public release of the anonymized data and their associated analysis tools were also discussed.

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Marais, Johannes Izak Frederik. "A permittivity measurement system for high frequency laboratories". Thesis, Link to the online version, 2006. http://hdl.handle.net/10019/580.

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Williams, Benjamin Heathcote. "Nano- and micro-scale techniques for electrical transport measurements". Thesis, University of Oxford, 2016. https://ora.ox.ac.uk/objects/uuid:09c73d9f-b68d-4f06-9ffe-cbb29d200809.

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This thesis outlines the development of two new techniques that exploit very small structures, on the micro- and nano-scale, to enable innovative electrical transport measurements on a variety of materials of current interest in condensed matter physics. The first technique aims to apply the versatility of electron-beam lithography for micro-fabrication of patterned electronic circuitry to the problem of performing transport experiments on individual crystallites taken from a typical powder sample. We show that these small samples, tens of microns in size, are actually often very high quality single crystals and can be exploited for measurements of electrical transport in materials of which no larger crystals are available. By way of demonstration, we present the results of preliminary transport measurements on a crystallite of the layered oxide chalcogenide Sr₂MnO₂Cu_1.5Se₂. We report a phase transition in the resistivity at 213K which may correspond to the onset of previously reported short-range order in copper and vacancy sites in the Cu_1.5Se₂ planes. The second technique is designed to investigate the topological protection of surface transport in 3-D topological insulators. We decorate the surfaces of single-crystal samples with two different species from a well-characterised family of single-molecule magnets. The two coatings have an electrostatically identical influence on the sample surface, but differ in that one species carries a spin and the other is spinless. The spinless molecule acts as a control, to allow us to cleanly determine the influence of the magnetic component of a scattering potential on transport in the surface. With this technique we investigate proposed topological Kondo insulator SmB₆. We find that the surface state dominates low-temperature transport and demonstrate that the momentum relaxation is very sensitive to a spin degree of freedom in the scatterer, in keeping with expectations of a topological insulator.

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Agjee, F. M. D. E. (Faatima Moosa Dawood Ebrahim). "A wideband signal conditioning system for high voltage measurements using a transconductance topology". Thesis, Stellenbosch : Stellenbosch University, 2000. http://hdl.handle.net/10019.1/51633.

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Thesis (MScEng)--Stellenbosch University, 2000.
ENGLISH ABSTRACT: Recent research has shown that standard substation capacitive voltage transformers (CVTs) and current transformers (CTs) can be used for the measurement of wideband high voltage phenomena by employing these apparatus in a transconductance topology. With this topology the voltage waveform can be obtained by integration of the ground return current in the earth straps of the CVT and the CT. This technique does, however, impose unique requirements on the amplification and integration instrumentation due to large dynamic range requirements and the strict offset specifications required for accurate integration. This thesis describes a programmable, wideband signal conditioning system for high voltage (HV) measurements using the transconductance topology. A suitable system topology, optimised to reduce the problems usually associated with grounding and electromagnetic interference (EMI) in HV environments, is proposed. This system consists of an analog signal conditioning subsystem, a digital signal conditioning subsystem and a high speed serial fibre-optic link. The analog signal conditioning subsystem conditions the signals from a sensor to levels suitable for the digitiser of the digital signal conditioning subsystem. The high bandwidth specification of the application made it necessary to consider both discrete and integrated implementation of the analog signal conditioning subsystem. Based on the simulated and laboratory test results of both implementations, the optimum design was chosen for the developed system. The digital signal conditioning subsystem, which performs the integration, as well as the serial optic-fibre link control logic was implemented using programmable logic array (PLA) technology. The digital data is transmitted across the fibre-optic link. This data is then converted back to an analog signal. Keywords: High voltage measurements, Transconductance topology.
AFRIKAANSE OPSOMMING: Onlangse navorsing het aangetoon dat standaard substasie kapasitiewe spanningstransformators en stroomtransformators gebruik kan word om wyeband hoogspanningsverskynsels te meet deur hierdie apparatuur in 'n transkonduktansie topologie aan te wend. Met hierdie topologie kan die spanningsgolfvorm verkry word deur die integrasie van die aardstrome in die aardverbindings van die kapasitiewe spanningstransformators en stroomtransformators. Hierdie tegniek stel egter unieke vereistes vir die versterkings- en integrasieinstrumentasie te wyte aan groot dinamiese bereik vereistes en die streng afset spesifikasies wat benodig word vir akkurate integrasie. Hierdie tesis beskryf 'n programmeerbare, wyeband seinkondisioneringstelsel vir hoogspanningsmetings deur van die transkonduktansie topologie gebruik te maak. 'n Geskikte stelseltopologie, wat geoptimiseer is om probleme, wat gewoonlik met aarding en elektromagnetiese interferensie in hoogspanningsomgewings geassosieer word, te verminder, is voorgestel. Die stelsel bestaan uit 'n analoog seinkondisioneringsubstelsel, 'n digitale seinkondisioneringsubstelsel en 'n hoëspoed seriële optiese vesel koppelvlak. Die analoog seinkondisioneringsubstelsel kondisioneer die seine vanaf 'n sensor na geskikte vlakke vir die versyferaar van die digitale seinkondisioneringsubstelsel. Die hoë bandwydte spesifikasie van die toepassing vereis die inagneming van beide diskrete en geïntegreerde implementerings van die analoog seinkondisioneringsubstelsel. Gebaseer op gesimuleerde en laboratorium toetsresultate van beide implementerings is die optimale ontwerp vir die ontwikkelde stelsel gekies. Die digitale seinkondisioneringsubstelsel wat die integrasie uitvoer, asook die seriële optiese vesel koppelvlak beheerlogika is geïmplementeer met behulp van programmeerbare logika skikking tegnologie. Die digitale data word gestuur oor die optiese vesel koppelvlak. Hierdie data word dan terug geskakel na 'n analoog sein. Sleutelwoorde: Hoogspanningsmetings, Transkonduktansie topologie.

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Huertas-Rosero, Alvaro Francisco. "Lexical measurements for information retrieval : a quantum approach". Thesis, University of Glasgow, 2011. http://theses.gla.ac.uk/2697/.

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The problem of determining whether a document is about a loosely defined topic is at the core of text Information Retrieval (IR). An automatic IR system should be able to determine if a document is likely to convey information on a topic. In most cases, it has to do it solely based on measure- ments of the use of terms in the document (lexical measurements). In this work a novel scheme for measuring and representing lexical information from text documents is proposed. This scheme is inspired by the concept of ideal measurement as is described by Quantum Theory (QT). We apply it to Information Retrieval through formal analogies between text processing and physical measurements. The main contribution of this work is the development of a complete mathematical scheme to describe lexical measurements. These measurements encompass current ways of repre- senting text, but also completely new representation schemes for it. For example, this quantum-like representation includes logical features such as non-Boolean behaviour that has been suggested to be a fundamental issue when extracting information from natural language text. This scheme also provides a formal unification of logical, probabilistic and geometric approaches to the IR problem. From the concepts and structures in this scheme of lexical measurement, and using the principle of uncertain conditional, an “Aboutness Witness” is defined as a transformation that can detect docu- ments that are relevant to a query. Mathematical properties of the Aboutness Witness are described in detail and related to other concepts from Information Retrieval. A practical application of this concept is also developed for ad hoc retrieval tasks, and is evaluated with standard collections. Even though the introduction of the model instantiated here does not lead to substantial perfor- mance improvements, it is shown how it can be extended and improved, as well as how it can generate a whole range of radically new models and methodologies. This work opens a number of research possibilities both theoretical and experimental, like new representations for documents in Hilbert spaces or other forms, methodologies for term weighting to be used either within the proposed framework or independently, ways to extend existing methodologies, and a new range of operator-based methods for several tasks in IR.

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Ibraheim, K. S. "Angular and polarisation correlation measurements on the 2'1P and 3'1P states of helium". Thesis, University of Stirling, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.375414.

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Björnham, Oscar, i Tobias Sundqvist. "Measuring and modelling of humidity penetration in an electronic control unit". Thesis, Umeå University, Department of Physics, 2000. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-35150.

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Real world modeling has become a very useful tool when new designs and applications are tested before they are introduced on the market. A field that recently has discovered the possible use of modeling is reliability prediction. The reliability and lifetime of a component has until recently been based on months and years of testing. In order to shorten the test time it is possible to simulate the environmental effect on the components. Another advantage of modeling is that changes of large systems where many different components work together can easily be studied. Without modeling the reliability has to be tested over and over again if the system is redesigned since it is impossible to know how the new change will affect the reliability.

Since electronic circuits are being made smaller and smaller with the increasing demand of faster technology the circuits are very vulnerable to corrosion. A trend in the automotive industry is also to move the electronic devices from the benign environment in the cab to the hash environment on the driveline or the chassi. The most common way to protect the electronics from the hash environment is to put it into a protective covering, also called Electronic Control Unit (ECU). Even though the ECU is sealed, water can still enter the ECU in several ways and cause serious damages by corrosion. The corrosion rate of a component is among others depending of the environmental humidity and temperature. Knowing the humidity and temperature are therefore very important to be able to eliminate corrosion problems. In order to achieve a better understanding of the physics behind the failure and to improve the reliability of the ECU a model of the temperature and humidity penetration is built in this thesis.

There are several components in the ECU which all responds differently to water vapour. By measuring the humidity penetration in the ECU while components were added one by one, the physical properties of the components could be determined. Some properties were also determined through additional solubility measurements. The humidity penetration of the ECU is then predicted by inserting these properties into mathematical models in Simulink^Ó.

The conclusion is that it is possible to model the humidity penetration and the temperature changes in the ECU. After the physical properties of the components were determined, the diffusion model agreed well with measurements. The numerical method used in this thesis has been found to be fast and stable. The length of the time-steps has been varied from a couple of minutes to more than an hour in the numerical model. A few physical properties has to be examined more in detailed and the model is then going to be a good foundation on which corrosion and other damaging processes can be modelled.

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Rajagopal, Seshadri. "Development and evaluation of a streamflow forecasting tool to improve reclamation operational water supply forecasts in the Carson River /". abstract and full text PDF (free order & download UNR users only), 2006. http://0-gateway.proquest.com.innopac.library.unr.edu/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:1440929.

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Thesis (M.S.)--University of Nevada, Reno, 2006.
"Fall, 2006." Includes bibliographical references (leaves 66-67). Online version available on the World Wide Web. Library also has microfilm. Ann Arbor, Mich. : ProQuest Information and Learning Company, [2006]. 1 microfilm reel ; 35 mm.

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Chen, Chang. "A voice controlled measurement procedure for the high energy physics laboratory". Virtual Press, 1990. http://liblink.bsu.edu/uhtbin/catkey/770952.

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A Zenith-386 workstation was outfitted with a DICRES-54.8 paralell port board to facilitate I/C between a large Summagrid x-y coordinate digital measurement pad that has a resolution of 10 microns. Film views of high energy particle collisions can be projected onto this pad for measurement. Voice prompts via a Votrax speech synthesis system are sent at critical points during the algorithm from the Z-386 through other ports of the DICRES board. Progress in measurement is fed into the Z-386's serial port from an Interstate voice recognition system at other points of the measurement algorithm. The whole measurement process is managed by an assembler language based modular computer program.
Department of Physics and Astronomy

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Mejergren, Henrik. "Multipoint Measurements of Magnetic Holes in the Pristine Solar Wind". Thesis, KTH, Skolan för elektroteknik och datavetenskap (EECS), 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-290371.

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Satellite data from the Cluster satellites have been used to find and evaluate structures in the pristine solar wind, referred to as magnetic holes. By using multipoint measurements, size and orientation-estimates are established. Other characteristics of interest are also examined, such as velocity, temperature, density, and pressure. The results show that the magnetic holes vary in both shape and size, but with a median difference between the minor and major axis by a factor of five. Most of the events also show increases in both density and ion temperature compared to background values. Comparisons have been made with studies of similar structures downstream of the bow shock referred to as plasmoids which show an even more flattened shape in the direction of the plasma velocity. This study did however not find any such correlations when looking at projections in the GSE-coordinate system. This could suggest that these structures are being compressed in the direction of the velocity as they travel past the bow shock, most likely due to the drastic decrease in velocity. Furthermore, no distinct correlation is found between the size of the MH and the drop of magnetic field strength.
Satellitdata från Cluster-satelliterna har använts för att hitta och utvärdera strukturer i den orörda solvinden, kallade magnetiska hål. Genom att använda flerpunktsmätningar fastställs storlek och orienteringsuppskattningar av dessa. Även andra egenskaper av intresse undersöks, såsom hastighet, temperatur, densitet, och tryck. Resultaten visar att de magnetiska hålen varierar både i storlek och form, med en storaxel som är cirka fem gånger större än lillaxeln om man tittar på medianvärdet. De flesta magnetiska hål visar ökningar i både densitet och jontemperatur jämfört med bakgrundsvärden. Jämförelser har gjorts med studier av liknande strukturer, nedströms bågchocken som kallas plasmoider. Dessa visar en ännu mer tillplattad form, i plasmahastighetens riktning. Denna studie hittade dock inga sådana korrelationer när man tittade på formen i GSE-koordinater. Detta kan tyda på att dessa strukturer komprimeras i hastighetens riktning när de färdas förbi bågchocken, troligtvis på grund av den drastiska minskningen av hastigheten. Studien visar inte heller någon tydlig korrelation mellan storleken på hålen och dess minskning av magnetfältstyrkan.

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Mazomenos, Evangelos. "A real-time target tracking system for wireless embedded nodes using ranging measurements". Thesis, University of Southampton, 2012. https://eprints.soton.ac.uk/336229/.

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The area of wireless embedded nodes has attracted significant research interest, primarily with respect to the utilisation of this technology in a number of applications domains. Under this context, the main topic of this thesis pertains to the design of a framework for real-time, range-only target tracking utilizing low power wireless embedded nodes. The proposed tracking system is designed to operate solely on range measurements which are obtained without the need for additional hardware incorporated on the embedded nodes. The core objective of this research was to present a target tracking system that can be applied to real-world applications, incorporating support for effectively tracking manoeuvring targets facilitated by the ability to obtain accurate range readings from low-power embedded nodes and finally the ability to achieve real-time system operation. The contribution of the work presented in this thesis is threefold. The tracking problem is theoretically formulated as a dynamical system with the objective being, the real-time estimation of the target’s kinematic variables based on range observations. To address the need for effective tracking of manoeuvring targets an adaptive multiple-model approach was developed. The resulting system is non-linear, due to the non-linearity between the range observations and the kinematic variables. To solve this system, a novel adaptive multiple-model Particle Filter tracking algorithm is proposed. Secondly, to achieve accurate enough ranging between embedded nodes a Time-of-Flight ranging scheme is adopted as part of the proposed tracking system. The final contribution of this work pertains to the real-time operation of the tracking system. The tracking algorithms were evaluated on a simulation environment under realistic experimental conditions. The ranging method was implemented on embedded nodes and tested in terms of accuracy in various environments. Ultimately, the entire system was implemented on hardware and tested in outdoor experiments. In the experiments carried out one mobile wireless node was used as the target and a set of anchor nodes attempted to infer the target’s kinematic variables. A total of 25 experiments are presented in this thesis. An average accuracy of approximately 2.6m for position and 1.9m/s for velocity was attained in a 15m x 15m square area. Such performance, which is confirmed from the simulation results reveal the potential of the proposed range-only system in application domains where real-time tracking of mobile targets is a demand.

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Pankow, Joel Walter. "Effects of dopant molecules on the electronic properties of organic thin films: Solid state conductivity measurements and surface electron spectroscopic techniques". Diss., The University of Arizona, 1991. http://hdl.handle.net/10150/185399.

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Organic molecular electronic materials are used in many applications such as chemical sensors, p-n junction devices, photovoltaics and xerography. Chlorogallium phthalocyanine (GaPc-Cl), shown by previous research in this group to have exceptional photoelectrochemical properties and sensitivity to chemical dopants such as oxygen and hydrogen, is suspected to be influenced by growth conditions and subsequent exposure to ambient conditions. GaPc-Cl films were grown on interdigitated array microcircuits in an ultra high vacuum chamber and several solid state parameters (in vacuum) were measured. This yielded information concerning: structural trap concentration; chemical impurity concentration and energetic levels; trap depths; ohmic or space charge limited current behavior; quantum efficiencies; and, photocurrent sensitivity to changes in illumination intensity. Films with higher chemical impurity concentrations had larger rise and decay times; high dark currents and low dark activation energies; larger photoactivation energies; a poor contrast of photo-to-dark current; extended ohmic regions in dark current-voltage curves; enhanced absorbed light quantum efficiencies; and low sensitivity of photocurrent to changes in light intensity. Chemical dopants (O₂, NH₃, NO₂ and TCNQ) were then chemisorbed on the films and uptake curves were obtained by monitoring dark and/or photocurrent responses. Solid state measurements were repeated for comparison and contrast to the native state. O₂ and NH₃ cause irreversible dark and photocurrent decreases followed by reversible dark and photocurrent increases. TCNQ and NO₂ caused immediate reversible photo and dark current increases. Solid state parameters varied depending on whether the dopant was surface-bound (TCNQ), or could intercalate into the bulk (O₂, NH₃ and NO₂). XPS and UPS experiments were conducted on native GaPc-Cl or TCNQ films and bilayers of these two compounds. UPS established HOMO levels for GaPc-Cl and TCNQ and substantiated feasibility of GaPc-Cl oxidation; however, no useful XPS/UPS information was obtained for reactions between GaPc-Cl and TCNQ primarily because of overlapping spectral regions. XPS quantitation of TCNQ peak areas established identities of carbon atoms responsible for them. TCNQ deposition on various work function metals demonstrated the identity of TCNQ carbons susceptible to reduction.

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Forsberg, Johan. "Mobile robot navigation and map generation using range measurements". Licentiate thesis, Luleå tekniska universitet, EISLAB, 1995. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-17818.

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This thesis is on mobile robot navigation using range sensors. The two sensors types used are time-of-flight lasers and sheet-of-light range cameras, both giving densely spaced range measurements. Map generation and navi gation are achieved in indoor environments, even when there are lots of disturbing objects giving cluttered range measurements. The walls are observed in the range scans using the Range Weighted Hough Transform, (RWHT) and the estimates of the map and the robot position are maintained during motion using Extended Kalman Filtering (EKF). The calibration of sensor parameters during operation uses the relative motion given by the incremental encoders on the wheels as the absolute calibration reference. Matching of observations to previous estimates are performed using a deci sion directed classifier. The algorithms can be used both to build a map, or during navigation using an existing map. The algorithms have been verified in several experiment with the range sensors onboard actual mobile robots. The size of a large room was estimated with a standard deviation of 1 cm. The robot navigates autonomously through an open door detected by the laser. The accuracy during passage was 1 cm at a speed of 0.5 m/s. The trajectory is perpendicular to the wall within 0.5 degrees. In one experiment the robot created a map of its environment while moving at speeds from 0.5 to 1 m/s. The standard deviation in the esti mated map dimensions for a series of tests were 1 to 2 cm and 1 degree. The navigation system has also been used for an autonomous plastering robot with automatic planning to include doors and windows. The navigation is very robust against both outliers in the measurements and disturbing objects. It is not seriously disturbed even when most of the walls are occluded and there are several persons moving around during operation.

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Putta, Sunil Kumar. "Nodal Resistance Measurement System". Thesis, University of North Texas, 2005. https://digital.library.unt.edu/ark:/67531/metadc5568/.

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The latest development in the measurement techniques has resulted in fast improvements in the instruments used for measurement of various electrical quantities. A common problem in such instruments is the automation of acquiring, retrieving and controlling the measurements by a computer or a laptop. In this study, nodal resistance measurement (NRM) system is developed to solve the above problem. The purpose of this study is to design and develop a compact electronic board, which measures electrical resistance, and a computer or a laptop controls the board. For the above purpose, surface nodal points are created on the surface of the sample electrically conductive material. The nodal points are connected to the compact electronic board and this board is connected to the computer. The user selects the nodal points, from the computer, between which the NRM system measures the electrical resistance and displays the measured quantity on the computer.

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Khan, Zulfiqar A. "EMI/EMC analysis of electronic systems subject to near zone illuminations". Columbus, Ohio : Ohio State University, 2007. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1196207323.

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Stevens, Pieter. "Exitability measurements through indoor 3D GIS". Thesis, Högskolan i Gävle, Samhällsbyggnad, GIS, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:hig:diva-27994.

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Population growth, city expansion and the limitation of space is shifting construction into a vertical direction. Residential or public constructions as well as office buildings are growing vertically, especially in big cities. Along with the verticality, evacuation problems popped up. The higher buildings are rising the longer it takes to get people safely to the nearest exit. The primary concern for emergency response and rescue is the time needed to evacuate. Evacuation processes are highly contingent to building structure as built and not necessarily as designed. Throughout construction minor modifications are made and in evacuation planning it is eminent that the most accurate and up to date information is used.In this dissertation the focus is laid on the evacuation capability of the Munin building of the Hogkolan I Gävle. This research uses network analysis and network routing in an indoor three dimensional (3D) geographic information system. Exitability is defined as the ease to get to the nearest exit. This is a crucial factor in evacuation modelling and planning. In order to calculate the exitability a three dimensional model of the building is created along with a network dataset. The building model is analyzed based on three different scenarios, for different paces on the five different floor levels resulting into a matrix of evacuation paths. The easiest way out from each room in the building to the nearest exit is calculated and listed. By representing the exitability, the evacuation plan of the building can be revised and if needed adjusted. The created model can be used as a tool in decision making considering the time needed to get to the nearest exit.The importance of the implementation of network routing in GIS to improve evacuation plans can be found in development phase as well as whilst emergencies. During emergencies the shortest path for search and rescue can be found considering blocked paths. Throughout development the placement of exits and the amount of exits can be tested using the system. By simulating emergencies, bottlenecks and hazardous situations can be reconciled and doing so improve the evacuation plans. The influence of different scenarios on the exitability can be reduced to influence the scenarios have on the covered distance to the nearest exit. The different scenarios show a translation of linearity. The different scenarios give an insight in the congestion of the exits, which can be used for emergency planning. Future-minded it is preferable this theoretical model is compared to real-time results.

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Miller, Jeff. "On the possibility of detecting low barrier hydrogen bonds with UV spectroscopy and kinetic measurements /". Electronic version (PDF), 2004. http://dl.uncw.edu/etd/2003/millerj/jeffmiller.pdf.

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Nyström, Stefan. "Evaluation of a New Method for Extraction of Drift-Stable Information from Electronic Tongue Measurements". Thesis, Linköping University, Department of Electrical Engineering, 2003. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-1615.

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This thesis is a part of a project where a new method, the base descriptor approach, is studied. The purpose of this method is to reduce drift and extract vital information from electronic tongue measurements. Reference solutions, called descriptors, are measured and the measurements are used to find base descriptors. A base descriptor is, in this thesis, a regression vector for prediction of the property that the descriptor represent. The property is in this case the concentration of a chemical substance in the descriptor solution. Measurements from test samples, in this case fruit juices, are projected onto the base descriptors to extract vital and drift-stable information from the test samples.

The base descriptors are used to determine the concentrations of the descriptors'chemical substances in the juices and thereby also to classify the different juices. It is assumed that the measurements of samples of juices and descriptors drift the same way. This assumption has to be true in order for the base descriptor approach to work. The base descriptors are calculated by multivariate regression methods like partial least squares regression (PLSR) and principal component regression (PCR).

Only two of the descriptors tested in this thesis worked as basis for base descriptors. The base descriptors'predictions of the concentrations of chemical substances in the juices are hard to evaluate since the true concentrations are unknown. Comparing the projections of juice measurements onto the base descriptors with a classification model on the juice measurements performed by principal component analysis (PCA), there is no significant difference in drift of the juice measurements in the results of the two methods. The base descriptors, however, separates the juices for classification somewhat better than the classification of juices performed by PCA.

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Nordin, Daniel. "Optical frequency modulated continuous wave (FMCW) range and velocity measurements". Doctoral thesis, Luleå, 2004. http://epubl.luth.se/1402-1544/2004/43.

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Kusekwa, Mashauri A. D. "Real-time state estimation of a distributed electrical power system under conditions of deregulation". Thesis, Cape Peninsula University of Technology, 2010. http://hdl.handle.net/20.500.11838/2186.

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Thesis (DTech (Electrical Engineering))--Cape Peninsula University of Technology, 2010.
Static state estimation is a mathematical procedure in which physical measurements from sub-stations and physical model are combined in an optimal way. That is, the measurements obtained from the sub-stations are used with the physical model and the states of the power system are selected or calculated such that the states match the measurements in some best way. The states of a power system are the bus voltage magnitude and voltage angle of each bus of the system. Static state estimation is an increasingly common part of electrical power utility energy management systems (EMS). It plays a critical part in a day-to-day operation of a power system utility. The system measurements obtained from static estimation are used for realtime operations like optimal power flow calculations and contingency analysis. Proper system operations with regards to avoidance of insecure conditions includes situational awareness, therefore, the static estimator plays an important role in power system security. A further motivation: in increasingly electrical power deregulation, more economic operations mean savings for customers and electrical power provider alike. Economic benefit might be realized if system operators have a more accurate situational awareness of the system through improved power system state estimator. The objective of the study was to develop method, algorithm and MATLAB program for solution of power system state estimation using parallel processing techniques. In achieving the objective, the study has concentrated on development of an approximate Tanzanian power system network model comprising of 30 buses and used as a case study; decomposing the bus admittance matrix of the model into 3 interconnected sub-systems; development of mathematical model for real and reactive power injections, real and reactive power flows in the transmission lines and tie-lines connecting the sub-systems; development of measurement data model for voltage magnitude, real and reactive power injections, real and reactive power flows; formulating of a constrained weighted least absolute value state estimation problem; development of decomposition-coordination method and algorithm; and formulating algorithm and MATLAB program for solving the constrained state estimation problem using parallel processing technique.

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Moberg, Caroline. "Development of measurement algorithm in an industrial PLC : An evaluation of DSOGI-PLL for real time measurements". Thesis, Uppsala universitet, Institutionen för teknikvetenskaper, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-388490.

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The aim of this project was to devise an algorithm for three phase AC power grid measurements that could be utilized in an excitation system for controlling generators. This application requires fast and accurate measurements even when the voltages in the power grid are characterized by unbalanced three-phase, frequency variations and harmonic distortions. Phase locked loop algorithms are used in grid synchronization techniques and are developed to withstand disturbances in the power grid. A DSOGI-PLL was implemented on a PLC and then evaluated. The DSOGI-PLL was tested with input voltages generated by a relay testing system. The result showed that the DSOGI-PLL could measure positive sequence component RMS and grid frequency of unbalanced three-phase voltages and voltages characterized by frequency variations and harmonic distortions. However, the measurements response time and accuracy did not meet the requirements for application in excitation systems.

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Willis, Sarah Potter. "The effects of high stakes testing on the teaching practices of National Board Certified Teachers /". Electronic version (PDF), 2007. http://dl.uncw.edu/etd/2007-1/williss/sarahwillis.pdf.

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