M.Sc. (Chemistry) / In this investigation a monostandard calibration technique was developed for multi-element X-ray fluorescence analysis. A reliable method is described for the calculation of slopes of calibration lines for thin-film and powder samples using monochromatic as well as polichromatic excitation. Theoretically calculated slopes for elements within one serles, e.g. the K-series, were normalised .using one or two known slopes for elements in the series. The mathematical equations used to -. interpolate slopes as a function of atomic number, were based on the fundamental relationship between fluorescent intensity and atomic number, fluorescent yield, detector efficiency, concentration and mass absorption coefficients. Kramer's formula was used to approximate the shape of the" primary radiation spectrum. The method was applied to the analysis of the K-series elements, with the use of thin-film and powder samples. The excitation was achieved by the use of a molybdenum-, gold-, tungsten- and chrome anodes. The method was also applied to the analysis of the L-series powder samples. The monochromatic excitation of the L-series elements, achieved with the use of a molybdenum anode, is also described. The polichromatic excitation of the L-series powder samples was obtained with a molybdenum-, gold-, tungsten- and chrome anode.

Seventeen square-edged orifice plates were calibrated to study the effect of varying throat length, both in the absence and in the presence of geometrical similarity, on the coefficient of discharge for pipe Reynolds numbers from 20 to1 10,000. The experiments involved the use of hydraulically smooth pipe in test lines of 1 - inch, 1.5 - inch and 2 - inch nominal I.D., corner pressure taps and Beta ratios (orifice diameter/pipe diameter) of 0.2, 0.4 and 0.6. Six of the plates were built using design criteria recommended by the A.S.M.E. in "Fluid Meters" (1), and with Beta ratios specified at 0.4. Each test line was used with two plates, which were identical except for a variation in throat length within the range of the given design recommendations. A comparison of discharge coefficients as a function of pipe Reynolds number indicated the following: (1) Reynolds numbers 30 - 3,000. Consistent differences of 2-6% were observed in the calibration curves due to the variation in throat length allowed by "Fluid Meters".(1). (2) Reynolds number 3,000 - 10,000. Geometry appeared to be much less important, as all calibration curves tended to coincide. Two further plates, for the 1.5 - inch pipe only, were built using the A.S.M.E. "Power Test Code" (2) as a design reference. They were designed to have respectively the minimum and maximum throat length allowable under the code. The results, when plotted, indicated that in a pipe Reynolds number range of 40 - 1,500, plates built identically except for small differences in throat length, still gave distinguishably different calibration curves. The remaining nine plates were divided into three groups of three plates each, encompassing the three pipe diameters and three Beta ratios. All plates within a group were geometrically similar. The results, for pipe Reynolds numbers from 20 to 2,000, indicated that a total specification of orifice shape gave consistent calibration curves with no apparent absolute size effects. Thus, both "Fluid Meters" *and the "Power Test Code" recommended design criteria for standard orifice plates which do not completely take into account the effect of geometry on the coefficient of discharge at low Reynolds numbers. In particular, the tolerances allowed on throat length are too large. / Applied Science, Faculty of / Chemical and Biological Engineering, Department of / Graduate

With general advancements in computer technology and development ofdirect geo-referencing technology, such as GPS, airborne laser scanningsystems came into widespread use especially after 2002. In spite of relativelyhigh cost of purchase, the systems proved to be cost effective, providing fastand in large volumes 3D geospatial data acquisition with unprecedentedaccuracy and relatively modest processing complexity. Country-widecollection of laser scanning data, mainly due to DTM derivation, is becomingan attractive possibility for mapping. Since 2009, Swedish Government hasapproved and financed the project of developing the New National ElevationModel (NNH) for the country of Sweden, with aspects of monitoring climatechanges and other environmental impacts. The National Land Survey ofSweden, which is commissioned to carry out the project, is offering this highlyaccurate scanned data less expensive to secondary users, such as companiesspecialized in forestry applications, etc. Beside the geospatial data (X, Y, Z),laser systems additionally record the received signal intensity for eachmeasurement. So far, intensity values were just an additional variable, notused extensively, but in recent years many efforts have been made tounderstand and interpret these values. The wider use of intensity data ismissing due to the lack of techniques to calibrate them, so that theyrepresent values proportional to the scattering characteristics of the target. Inthe scope of this thesis it was examined which properties influence intensityvalues and to what degree. Already proposed methods for calibration weresummarized and the most suitable one was implemented based on the datafrom the NNH project and instruments used for it. The results proved to begood both empirically and visually, with reduced intensity variations over thesame targets. The potentials of using this corrected data are presented, suchas surface classification, automatic object recognition, multi-temporalanalysis, and more.

The Objective of the Remote Measurements Calibration (RMC) method is to minimize systematic errors through an appropriate scaling procedure. A new method for RMC has been developed. This method solves the problems of observability, multiplicity of solutions, and ambiguity of reference points associated with the method proposed by Adibi et. al. [6-9]. The new algorithm uses the simulated annealing technique together with the matroid method to identify and minimize the number of RTUs (Remote Terminal Units) required to observe the system. After field calibration, these RTUs provide measurements that are used to estimate the whole state of the system. These estimates are then returned as a reference for remotely calibrating the remaining RTUs. The calibration coefficients are estimated by means of highly robust estimator, namely the Least Median of Squares (LMS) estimator. The calibration method is applicable to large systems by means of network tearing and dynamic programming. The number of field calibrations can be decreased further whenever multiple voltage measurements at the same buses are available. The procedure requires that the measurement biases are estimated from recorded metered values when buses, or lines, or transformers are disconnected. It also requires the application of a robust comparative voltage calibration method. To this end, a modified Friedman test has been developed and its robustness characteristics investigated. / Ph. D.

Neutrinos hold the promise of untangling many unresolved questions in particle physics. Their unique properties and behaviors offer a distinctive window into understanding the fundamentals of the universe, potentially providing answers to some of the most deep puzzles in modern physics. CEνNS, or Coherent Elastic Neutrino-Nucleus Scattering, is a process where a neutrino interacts with an atomic nucleus and scatters away, leaving the nucleus to recoil. CEνNS is an important area of study for understanding neutrino properties as well as their role in the universe. The COHERENT collaboration was the first to measure CEνNS, using neutrinos from the Spallation Neutron Source (SNS). The direct measurement of the SNS neutrino flux is vital for the precision of CEνNS measurements. This work introduces the latest addition to the COHERENT's armory –a D2O detector specifically designed to measure the SNS neutrino flux. In the present dissertation, the emphasis is made on the steps taken to operationalize COHERENT's D2O detector. This work unfolds the intensive simulation work directed to determine the detector's optimal design, ensuring it stands strong to the demands of neutrino physics experiments. Establishing the detector's calibration is essential to its operational phase. A dedicated calibration system, described in detail in this work, has been developed, utilizing encapsulated LED flashers controlled by a microcontroller unit to ensure the systematic and reliable calibration of the detector. A significant portion of the document is devoted to the calibration analysis, where we use Michel electrons to obtain an energy scale for the detector, thereby ensuring the reliability and accuracy of the future neutrino flux measurements. / Doctor of Philosophy / This dissertation delves into the fascinating world of neutrinos, subatomic particles that travel through space and matter, impacting the universe in many ways. Their elusive nature makes them a fascinating subject of study, as understanding them better can reveal more about the fundamentals of the cosmos. One process involving neutrinos is Coherent Elastic Neutrino-Nucleus Scattering (CEνNS), which is the main focus of the COHERENT experi- ment. CEνNS happens when a neutrino interacts with an atomic nucleus and scatters away. It is a vital field of study as it can provide insights into neutrino properties and behavi- ors, helping us explore many unanswered questions in physics. As part of COHERENT's experimental program, there is the need to measure the neutrino flux directly. This pre- cise measurement is crucial for ensuring the accuracy and reliability of the COHERENT's findings. To achieve this, COHERENT has introduced a new detector, filled with heavy water (D2O), designed to carefully capture and analyze neutrinos. This work outlines the extensive simulation undertaken to ensure the detector's effectiveness. Before the detector can successfully measure neutrino interactions, it must be carefully calibrated. This docu- ment also describes the construction of a unique calibration system, a critical step for the project's success. Finally, this dissertation highlights the development of a detailed calibra- tion analysis, an essential component for ensuring the detector's readings are accurate and trustworthy. This comprehensive preparation is fundamental for the next exciting phases of COHERENT's research into the mysterious world of neutrinos.

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The flavor oscillations of neutrinos due to the mixing of mass eigenstates have been thoroughly studied in several experiments. One missing piece of the puzzle is the mixing angle θ13, which is being searched for by the Daya Bay experiment. Currently, the experiment is still in construction mode. Part of the experiment involves building effective detectors for atmospheric muons, resulting in accurate detection of antineutrinos from the source. To ensure accurate detection, we must effectively calibrate the PMTs with the use of carefully chosen and calibrated LEDs. This thesis details the study of several LEDs measured in an attempt to determine the properties of the most likely source for our calibration efforts. I measured the spectra of the LEDs meant for use in calibration, along with several others for the purpose of comparison of spectrum width and to find the evidence of fluorescence in the LEDs. / Master of Science

Software Defined Radios (SDRs) are systems in which components such as filters, modulators, demodulators, etc., typically implemented in hardware are instead implemented in software. Thus, SDR systems shift signal processing from analog to digital domain. The signal processing is performed in reconfigurable devices like General Purpose Processors (GPP) or Field Programmable Gate Arrays (FPGA). The resulting flexibility of SDR systems brings in many advantages to wireless communications such as improved interoperability, adaptation capability and more future-proof hardware. Various prototype/laboratory friendly hardware are available such as Universal Software Radio Peripherals (USRPs), developed by Ettus Research, which in combination with software interfaces such as GNU Radio can be used to design and implement a Software Defined Radio(SDR) system. This has in turn enabled numerous research opportunities and advancements in field of wireless communication. However one major drawback of these simple USRP devices is that they are un-calibrated in terms of power or voltage and hence give the results in relative terms/counts. This poses a disadvantage in real world scenarios where parameters such as power measured in milliwatts or dBm, are used to design, implement, and test devices and systems and to collect and interpret experimental results. Lack of connectivity with these metrics leads to the USRP devices being confined to proof of concept implementation and demonstrations, and limits their utility for experimentation. In this thesis an attempt has been made to calibrate the USRPN210 (with WBX daughter board) devices and derive some calibration factors that would help relate the experimental results obtained from the USRP and GNU Radio combination to real world metrics. This also makes the result-set clearer and easily understandable. Several experiments were conducted to understand and characterize the performance of the USRP under different conditions. Experiments such as determination of 1-dB compression point, Third order intercept point helped understand the linearity range of the device under transmitter and receiver operations. The 3rd order input intercept point for USRPN210 device with WBX board with calibration was found to be around 0.25 dBm, which is closer to the expected value of 0 dBm at 400 MHz. Amplitude and frequency stability tests over the operational frequency range of the daughter board helped to note if change in frequency produced any variation in the received or transmitted power. Also variation with respect to gain helped derive a reference table for transmitted power, which could be used in for future experiments. Conducting these experiments over a sample of 10 USRPs helped in obtaining standardized values and benchmarking them. The factors obtained were also used in some experiments like path loss modeling, position location estimation in order to determine their effectiveness and impact on such applications. Although, these factors obtained may not be directly applicable to all USRP devices, as in any analog circuitry, and also since they are conducted relative to some specific applications such as the predefined spectrum analyzer utility of GNU Radio (UHD_FFT.grc), they do help to understand the basis of derivation of calibration metrics resulting from the various experiments and also provide a platform for future work in this area to obtain more uniform and globally acceptable results. All photos by the author unless cited, 2014. / Master of Science

Penetration of high velocity is of concern for both civilian and military research for decades, and computerized simulation is the scholar's focus in recent years. This study presents a study on the Discrete Element Method (DEM) simulation of plain concrete target's behavior under high-velocity penetration of rigid projectile. In this thesis, different types of research works including empirical, analytical and numerical methods in penetration by the previous scholars were carefully reviewed. A DEM-based concrete model was established by using software PFC3D. The major micro-variables of the simulation program were calibrated according to the required macro-mechanical parameters. Meanwhile, their correlations within the concrete range were studied, with the sensitivity analysis and the corresponding regression equations. With the established digital concrete model, penetration simulation tests were carried out. The results of penetration depth versus impact velocity were compared with the experimental and empirical calculated results from Forrestal's work in 1994. A good agreement was obtained. Some other simulation studies, like projectile mass, geometry, penetrating acceleration, concrete response stress, strain, and strain-rate were also conducted to study the constitutive properties in this thesis. / Master of Science

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