Dissertations / Theses on the topic 'Differential measurements'
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Smith, Martin Dignan. "Fibre interferometry for differential measurements." Thesis, Heriot-Watt University, 2015. http://hdl.handle.net/10399/2913.
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This thesis investigates the use of interferometry as an interrogation technology for the measurement of differential length at two widely separate locations. Differential length measurements are essential and can have many applications in industrial processes, therefore accurate measurements can be a critical. Such differential length measurements can be applied to aspects of differential pressure. Using an all optical fibre approach, the research utilises the effects of light interference for both low coherent and high coherent light sources for the determination of a differential length between individual sensing cavities separated by up to 10’s of meters. The construction of the differential length interrogation system makes use of two Fabry-Perot cavities arranged in a tandem configuration, as a means of determining the differential length between them. Such an arrangement provides a common path through which an optical broadband light source at a central wavelength of 1550 nm can propagate. As a consequence of this configuration, differential lengths are made simply using one single measurement, removing the need to determine each individual length. An additional benefit of this common optical path prevents environmental factors such as temperature and air pressures from affecting the measurement length in question. Using a scanning reference Michelson interferometer to induce an optical path change, low coherence interference effects are present when the optical path length of the differential Fabry-Perot cavities is equal to the optical path length difference in the Michelson interferometer. Using a separate DFB laser light source to illuminate the reference interferometer high coherence interference fringes, present when the optical path length of one interferometer arm is changing due to a piezo fibre stretcher, can be analysed to provide an accurate length determination. Taking into consideration the noise within the system the interrogation technique has a length measurement resolution of 27.43 nm. Demonstrations show that a differential length of 82.539 μm could be measured with an uncertainty of 41.00 nm. Through the characterisation of a deformable silicon diaphragm, it would be possible to construct a sensing system capable of measuring a differential pressure of 1 Pa in 100 kPa. This however would require a 9.13 mm thick diaphragm, with a radius of 0.35 m. Such a diaphragm would be out of the question and so further investigation into reducing the length measurement resolution would need to be carried out.
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Justo, Hernandez Ruiz. "Low differential pressure and multiphase flow measurements by means of differential pressure devices." Diss., Texas A&M University, 2004. http://hdl.handle.net/1969.1/1077.
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The response of slotted plate, Venturi meter and standard orifice to the presence of two phase, three phase and low differential flows was investigated. Two mixtures (air-water and air-oil) were used in the two-phase analysis while a mixture of air, water and oil was employed in the three-phase case. Due to the high gas void fraction (α>0.9), the mixture was considered wet gas. A slotted plate was utilized in the low differential pressure analysis and the discharge coefficient behavior was analyzed. Assuming homogeneous flow, an equation with two unknowns was obtained for the multi-phase flow analysis. An empirical relation and the differential response of the meters were used to estimate the variables involved in the equation. Good performance in the gas mass flow rate estimation was exhibited by the slotted and standard plates for the air-water flow, while poor results were obtained for the air-oil and air-water oil flows. The performance of all the flow meter tested in the analysis improved for differential pressures greater than 24.9 kPa (100 in_H2O). Due to the tendency to a zero value for the liquid flow, the error of the estimation reached values of more than 500% at high qualities and low differential pressures. Air-oil and air-water-oil flows show that liquid viscosity influences the response of the differential pressure meters. The best results for high liquid viscosity were obtained in the Venturi meter using the recovery pressure for the gas flow estimation at differential pressures greater than 24.9 kPa (100 in_H2O). A constant coefficient Cd was used for the low differential pressure analysis and results did show that for differential pressure less than 1.24 kPa (5 inH2O) density changes are less than 1% making possible the incompressible flow assumption. The average of the computed coefficients is the value of Cd.
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Langmore, Ian. "Inverse transport with angularly averaged measurements /." Thesis, Connect to this title online; UW restricted, 2008. http://hdl.handle.net/1773/5771.
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Lau, Condon. "Differential light scattering spectroscopy measurements for detecting and imaging cancer." Thesis, Massachusetts Institute of Technology, 2006. http://hdl.handle.net/1721.1/35666.
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Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2006.Includes bibliographical references.
Optical spectroscopy show great promise for diagnosing the earliest stages of cancer. Light scattering spectroscopy (LSS), the study of single elastic backscattering as a function of wavelength and angle, can detect subcellular structural changes in early cancer. We have developed two novel differential light scattering spectroscopy techniques, space differential LSS (SD/LSS) and b-angle differential LSS (/LSS), for detecting the single backscattering signal from a reflectance spectrum dominated by multiple scattering and diffuse reflectance. SD/LSS exploits the penetration abilities of diffuse reflectance while /LSS exploits the angular asymmetry of single backscattering from large particles. O/LSS has the added advantage of being able to isolate single backscattering specifically from scatterers much larger than the wavelength. We implement /LSS to interrogate colon tissue and to develop diagnostic algorithms based on Mie theory. The results show great promise for diagnosing cancer. Instrumentation is being developed to implement SD/LSS and /LSS together in a wide area imaging system with the goal of studying and detecting cancer at its earliest stages in vivo and in real time. The system has been validated with controlled tissue phantoms and will soon be ready for clinical studies.
by Condon Lau.
S.M.
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Sinreich, Roman. "Multi-Axis differential optical absorption spectroscopy measurements in polluted environments." [S.l. : s.n.], 2007. http://nbn-resolving.de/urn:nbn:de:bsz:16-opus-80698.
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Brown, Paulette C. "An empirical study of the consistency of differential item functioning detection." Thesis, University of Ottawa (Canada), 1992. http://hdl.handle.net/10393/7928.
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Total test scores of examinees on any given standardized test are used to provide reliable and objective information regarding the overall performance of the test takers. When the probability of successfully responding to a test item is not the same for examinees at the same ability levels, but from different groups, the item functions differentially in favour of one group over the other group. This type of problem, defined as differential item functioning (DIF), creates a disadvantage for members of certain subgroups of test takers. Test items need to be accurate and valid measures for all groups because test results may be used to make significant decisions which may have an impact on the future opportunities available to test takers. Thus, DIF is an issue of concern in the field of educational measurement. The purpose of this study was to investigate how well the Mantel-Haenszel (MH) and logistic regression (LR) procedures perform in the identification of items that function differentially across gender groups and regional groups. Research questions to be answered by this study were concerned with three issues: (1) the detection rates for DIF items and items which did not exhibit DIF, (2) the agreement for the MH and LR methods in the detection of DIF items, and (3) the effectiveness of these indices across sample size and over replications. (Abstract shortened by UMI.)
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Lee, Yoonsun. "The impact of a multidimensional item on differential item functioning (DIF) /." Thesis, Connect to this title online; UW restricted, 2004. http://hdl.handle.net/1773/7920.
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Reiners, Ansgar. "Measurements of differential rotation in line profiles of solar-like stars." [S.l. : s.n.], 2002. http://deposit.ddb.de/cgi-bin/dokserv?idn=96651338X.
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Ceteroni, Ilaria. "High-pressure adsorption differential volumetric apparatus (HP-ADVA) for accurate equilibrium measurements." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2021. http://amslaurea.unibo.it/22274/.
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The volumetric system is a commonly used experimental method for gas adsorption measurements. Starting from the conventional volumetric system (single-branched), the development of differential (double-branched) apparatus has been proposed to overcome some criticalities connected to the original design. The following study is focused on the assessment of the high-pressure differential volumetric apparatus (HP-ADVA) built at the University of Edinburgh in order to discover and characterise system peculiarities at different experimental conditions, in terms of temperature and pressure. To do this, an integrated approach is proposed: an initial experimental campaign has been performed to take confidentiality with the apparatus, then, the experimental results were the starting point for the development of a sensitivity and error analysis aimed at describing the effect of each operating parameter into the final result. In this regard, a different analytical approach, compared to the ones commonly proposed in literature, has been proposed to closely reproduce the real system. Beyond having obtained promising results, some criticalities, matching what originally hypothesized from the experimental campaign, have been noted: valve volume effect and temperature control and measurements have been discovered being crucial aspects, and, supposedly, source of errors leading to explain the unexpected results obtained by the experimental campaign. Moreover, the importance of symmetry maintenance among the branches has been repeatedly confirmed in the analysis. Some recommendations aimed at improving the system set-up have been moved regarding the installation of a temperature control system and more accurate temperature measurement devices. Additionally, an accurate assessment and characterisation of pneumatically-actuated valves, as well as of the differential pressure transducer used for pressure measurement, before the installation, could be useful to reduce inaccuracies.
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Andee, Yogadissen. "Advanced techniques for noise figure and noise parameters measurements of differential amplifiers." Thesis, Lille 1, 2015. http://www.theses.fr/2015LIL10133/document.
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Les circuits différentiels présentent de nombreux avantages par rapport aux circuits 2-ports classiques en termes d’immunité contre les bruits de mode commun, de tensions de sortie doublées et de réduction de distorsion d’ordre pair. Leur usage répandu crée une demande pour le développement de nouvelles techniques de mesures du facteur de bruit différentiel. Le chapitre 1 démontre que le facteur de bruit est fonction de la corrélation des ondes de bruit en sortie du circuit différentiel. Il n’existe toutefois aucun appareil capable de mesurer directement cette corrélation. Le chapitre 2 présente une technique originale pour mesurer cette corrélation. Elle utilise un coupleur hybride connecté aux ports de sortie du circuit différentiel selon 2 configurations de connexion. Cette approche permet de mesurer rigoureusement le facteur de bruit de tous types d’amplificateurs différentiels. Le chapitre 3 propose une technique pour mesurer la corrélation sans utiliser de coupleurs. Une étude de la structure différentielle permet de trouver une expression de la corrélation en fonction des puissances de bruit en sortie et des paramètres S. Une technique rapide et fonctionnelle est ainsi développée sur un analyseur de réseau 4-port pour mesurer le facteur de bruit d’un amplificateur différentiel. Cette approche sans coupleur est étendue à la mesure des paramètres de bruit d’un amplificateur différentiel. L’extraction des 4 paramètres de bruit se fait grâce à la méthode des impédances multiples en utilisant un synthétiseur différentiel d’impédance. Ce travail présente pour la première fois une technique sans coupleur pour la mesure des paramètres de bruit différentielsDifferential circuits have major advantages over single-ended circuits regarding immunity to common-mode noise, double voltage swing and reduction of even-order distortion. Their wide proliferation creates a need for the development of functional techniques for differential noise figure measurement. Chapter 1 shows that the noise figure of a 4-port circuit depends on the correlation of the noise waves at the output ports. However, no standard equipment is capable of measuring directly this correlation. Chapter 2 proposes an original technique for measuring the correlation of output noise waves. It makes use of a hybrid coupler connected to the differential DUT. The correlation is determined by using two configurations of connection between the DUT and the coupler. A rigorous and general technique for the noise figure measurement of differential amplifiers is developed from this approach. Chapter 3 proposes an original approach where no extra coupler is required. A study of the structure of a differential amplifier is performed where an expression of the correlation is calculated in terms of output noise powers and of the 4-port S-parameters. A fast and functional measurement technique using this method is developed on a 4-port network analyzer. This coupler-free approach is extended to the measurement of the noise parameters of differential amplifiers. The noise parameters are determined from differential source-pull measurements using a differential impedance tuner. This is, to the best of our knowledge, the first coupler-free technique developed for measuring differential noise parameters
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Kyei-Blankson, Lydia S. "Predictive Validity, Differential Validity, and Differential Prediction of the Subtests of the Medical College Admission Test." Ohio University / OhioLINK, 2005. http://www.ohiolink.edu/etd/view.cgi?ohiou1125524238.
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Chen, Dong Qi Kayla. "Gender-related differential item functioning analysis on the GEPT-kids." Thesis, University of Macau, 2018. http://umaclib3.umac.mo/record=b3953512.
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Li, Li. "Differential infrared radiometer-based thermometric instrument for non-contact temperature and friction measurements." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2001. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/MQ58841.pdf.
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Hurley, Noel P. "Resource allocation and student achievement: A microlevel impact study of differential resource inputs on student achievement outcomes." Thesis, University of Ottawa (Canada), 1995. http://hdl.handle.net/10393/9724.
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This study examined the relationships between resource allocation and student achievement using a modified version of a conceptual model designed by Bulcock (1989) within a general model proposed by Guthrie (1988). Five research questions were developed from a review of literature to investigate the relationship between microlevel student input variables and student output variables--both cognitive and affective. The mediating effects of the student perceptions of the quality of school life on student achievement outcomes were also examined. Multiple regression analyses were utilized and data were analyzed at both the individual and school levels. Models were used to investigate the indirect effects of the quality of school life on student achievement outcomes. Substantively meaningful relationships were identified between linguistic resources, language usage and reading outcomes; socioeconomic level, gender, linguistic resources, language usage, and mathematics achievement; gender, student attitudes, and student well-being. All grade eight Newfoundland students (10,146) were the subjects of the study. Participants in the study completed the Canadian Test of Basic Skills (CTBS) and the Bulcock Attitudinal Inventory (BAI). Females scored higher than males on every test of the CTBS and also had more favourable attitudes towards school as measured using the BAI. Urban students outperformed rural students by the equivalent of nearly one year on the CTBS scores. A variable was constructed to test Bernstein's (1961) theory of language discontinuity. Bernstein contended that the further an individual's language code departed from the standard language code in use in that society, the greater the difficulty that person would have in learning. The language code variable was constructed using the language usage score from the CTBS to create a continuous variable. This language code variable proved to be highly explanatory in that it explained a large percentage of the variance in reading achievement outcomes and in mathematics achievement outcomes. The measure for students' perceptions toward their schooling experiences explained a large percentage of the variance of student well-being. Two other noteworthy findings in the present study arose from relationships identified between mathematics achievement and independent variables. A strong relationship was identified between mathematics achievement and socioeconomic level. In general, the higher one's socioeconomic level the greater were the outcome measures in mathematics achievement. Indirect effects analyses produced a significant relationship between gender and mathematics achievement that favoured girls. The construction of the educational production function in the present study proved to be an accurate model. The present study contributed to research in several ways. This is one of the first studies that has employed Quality of School Life indicators as developed in the BAI in an educational production function model. A second contribution was the inclusion of microlevel student linguistic resources as predictors of cognitive achievement outcomes. The third contribution of the present study was the high percentage of variance of cognitive achievement outcomes explained by the modified Bulcock model.
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Orispää, M. (Mikko). "On point sources and near field measurements in inverse acoustic obstacle scattering." Doctoral thesis, University of Oulu, 2002. http://urn.fi/urn:isbn:9514268725.
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Abstract
The dissertation considers an inverse acoustic obstacle scattering
problem in which the incident field is generated by a point source and the
measurements are made in the near field region.
Three methods to solve the problem of reconstructing the support of
an unknown sound-soft or sound-hard scatterer from the near field
measurements are presented. Methods are modifications of Kirsch
factorization and modified Kirsch factorization methods. Numerical
examples are given to show the practicality of one of the methods.
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Raiford-Ross, Terris. "The impact of multidimensionality on the detection of differential bundle functioning using SIBTEST." unrestricted, 2007. http://etd.gsu.edu/theses/available/etd-07312007-191825/.
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Thesis (Ph. D.)--Georgia State University, 2007.Title from file title page. Carolyn F. Furlow , committee chair; Phillip Gagne, T. Chris Oshima, Valerie A. Miller, committee members. Electronic text (113 p. : ill.) : digital, PDF file. Description based on contents viewed June 24, 2008. Includes bibliographical references (p. 93-100).
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Mâsse, Louise C. "A presentation and comparison of some new statistical techniques in the analysis of polytomous differential item functioning: A Monte Carlo investigation." Thesis, University of Ottawa (Canada), 1994. http://hdl.handle.net/10393/9904.
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There is a need to develop and investigate methods which can assess the Item Response Differences (IRD) found in all the options of an item. In this study, such an investigation was referred to as Polytomous Differential Item Functioning (PDIF). The purpose of this study was to present and investigate the performance of four new approaches in the assessment of PDIF. The four approaches are a MANOVA (MCO) and a MANCOVA (MCA) approach applied to categorical dependent variables, a Polytomous Logistic Regression (PLR) approach, and an ANOVA analysis based on the item responses quantified by Dual Scaling (DS). In this study the effectiveness of these approaches (MCA, MCO, PLR, and DS) as well as the Log-Linear (LOG) approach of Mellenbergh (1982) were assessed under various conditions of test length, sample size, item difficulty, and the amount and location of PDIF. A two-parameter polytomous logistic regression model was used to generate the data. In this study, only uniform PDIF was introduced in the alternatives of the item. The type of PDIF simulated (e.g. uniform) in this study did not allow for a direct comparison of the nonuniform test of hypothesis between the Logistic (LOG and PLR) approaches and the MAN(C)OVA (MCA and MCO) approaches because the Logistic approaches test for a difference in logits while the MAN(C)OVA approaches test for a difference in proportions. It was shown in this study that varying the probability of choosing the alternatives resulted in uniform logit differences which did not only translate into uniform differences in proportions but also translated into nonuniform differences in proportions. These differences affected the interpretation of the PDIF results because the test of nonuniform PDIF for the Logistic procedures corresponded to a valid test of the null hypothesis while the MAN(C)OVA results for nonuniform PDIF had to be adjusted in order to yield a test which approximated a true test of the null hypothesis. The results of this study lend some optimism to the employment of the MCA and PLR approaches. (Abstract shortened by UMI.)
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Webber, Luke. "Differential Interferometry and Multiple-Aperture Interferometry for Retrieving Three-Dimensional Measurements of Glacial Surface Velocity." Thesis, Stockholms universitet, Institutionen för naturgeografi, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-145384.
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The measurement and monitoring of glacial surface velocity is important for many aspects of glaciology, such as determining the mass balance, for characterising the stability or instability of glaciers, or the identification of potential hazards from surging glaciers or Jökulhlaups, a type of glacial outburst flood. Predominately measurements of glacial surface velocity have been produced using either differential interferometry (DInSAR) applied to radar data, or offset-tracking applied to either optical or radar data. Both of these methods have their own set of limitations, notably the one-dimensional nature of DInSAR measurements, and the relatively low accuracy of offset-tracking. Instead using DInSAR and multiple-aperture interferometry (MAI) applied to ERS-1/2 Tandem SAR data, measurements of glacial surface displacements were obtained in the line-of-sight (LOS) and along-track directions respectively. Then using a weighted-least squares adjustment, the method for producing the full three-dimensional surface velocity field is presented and applied to the Svartisen glacial system, Norway and the Petermann Glacier, Greenland. The advantages and disadvantages of applying such a method were explored, of which interferometric coherence is found to be the largest factor in retrieving accurate measurements using MAI. Low interferometric coherence due to temporal decorrelation resulted in the inability to extract the full three-dimensional surface velocity field over the Bagley Icefield, Alaska, and the Mýrdalsjökull & Eýjafjallajökull ice caps, Iceland. A feasibility analysis into the use of Sentinel-1 data, revealed that the current revisit period is too large to maintain interferometric coherence between acquisitions, preventing the application of either DInSAR or offset-tracking in order to measure the surface velocity of the Blåmannsisen Glacier, Norway. Despite the limitations encountered, in part due to the selection of source data, MAI in tandem with DInSAR has been shown to be capable of measuring the three-dimensional surface velocity to a higher accuracy than offset-tracking when coherence is high. The methods used within have been developed to work with pre-processed single look complex (SLC) SAR data rather than raw unfocused SAR data, in an effort to improve their adoption and enable more accurate estimates of glacial surface velocity.
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McDonald, Michael K. "Differential absorption measurements of total column ozone during polar night using modified stellar Brewer spectrometer." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/nq21305.pdf.
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Scott, Timothy Anthony 1963. "Determining the extent of specific adsorption at a solid metal electrode utilizing differential capacitance measurements." Thesis, The University of Arizona, 1989. http://hdl.handle.net/10150/277097.
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The Hurwitz-Parsons method of analysis is employed utilizing a spreadsheet application on an IBM-AT. It is designed to calculate the extent of specific adsorption of an inorganic anion or neutral organic molecule at a solid electrode without knowledge of the point of zero charge. Up to eight bulk adsorbate concentrations represented by differential capacitance versus potential curves may be input. The curves can contain up to 100 points. Output is in units of moles/cm2 and is provided at 10 potentials for each bulk adsorbate concentration. A detailed overview and a formula list of the application are provided. A brief overview of the theories associated with the electrochemical double layer and a related literature review are included.
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Gavin, Jared Martin. "Triple differential measurements of single and multiple ionization of argon by electron and positron impact." Diss., Rolla, Mo. : Missouri University of Science and Technology, 2009. http://scholarsmine.mst.edu/thesis/pdf/Gavin_09007dcc806583d0.pdf.
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Thesis (Ph. D.)--Missouri University of Science and Technology, 2009.Vita. The entire thesis text is included in file. Title from title screen of thesis/dissertation PDF file (viewed May 4, 2009) Includes bibliographical references (p. 78-82).
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Wilson, Ann Wells 1962. "Logistic regression and its use in detecting nonuniform differential item functioning in polytomous items." Diss., The University of Arizona, 1993. http://hdl.handle.net/10150/284324.
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A computer simulation study was conducted to determine the feasibility of using logistic regression procedures to detect nonuniform differential item functioning (DIF) in polytomous items. A simulated test of 25 items was generated, of which the 25th item contained nonuniform DIF. The degree of nonuniform DIF in the 25th item was varied in four ways. Item scores were generated using Muraki's generalized partial credit model and the data were artificially dichotomized in three different ways for the logistic regression procedure. The results indicate that logistic regression is a viable procedure in the detection of most forms of nonuniform DIF; however, it was not sensitive to DIF that is uniform within score categories and nonuniform across score categories. Logistic regression procedures were also quite awkward in the polytomous case, because several regressions must be run per polytomous item and it was difficult to determine an omnibus result in most cases. Some logistic regression procedures, however, may be useful in the post hoc analysis of DIF in polytomous items.
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Martin, Philip Nathaniel. "Measurements of atmospheric trace gases using open path differential UV absorption spectroscopy for urban pollution monitoring." Thesis, Imperial College London, 2003. http://hdl.handle.net/10044/1/11299.
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Lee, Shane-Woei. "On-the-fly carrier phase ambiguity resolution without using pseudorange measurements for satellite-based differential positioning." Ohio : Ohio University, 1994. http://www.ohiolink.edu/etd/view.cgi?ohiou1178131540.
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IMANI, BEHZAD. "ESTIMATION OF WATER CONTENT, TRANSPIRATION RATE, AND WATER POTENTIAL OF COTTON FROM STEM DIAMETER MEASUREMENTS USING A LINEAR VOLTAGE DIFFERENTIAL TRANSFORMER." Diss., The University of Arizona, 1987. http://hdl.handle.net/10150/184005.
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The Linear Voltage Differential Transformer (LVDT) is an accurate sensor for stem diameter measurements. Based on the results of this dissertation it was found that stem diameter [mm] was related to water content [grams] of the cotton crop by the following equation: W(D) = 0.114(D)³ˑ¹⁸² Also the ratio of stem diameter contraction rate to the rate of water loss in cotton was experimentally determined to be: (dW/dt)/(dD/dt) = (0.166 [g min⁻¹])/(0.535 [μm min⁻¹]) = (.0469% per minute)/(.0039% per minute). Similarly the cellular water potential was derived to be a non linear function of stem diameter in cotton: ψ(t) - ψₒ = 2 ε ln (D(t)/ Dₒ) + πₒDₒ² [(1/D²(t)) – (1/Dₒ²)]. Based on this work, the grower can estimate the water content, transpiration rate and water potential of the cotton crops via stem diameter measurements. Moreover, a computer system can be implemented to remotely keep track of the water status of the field, and control the irrigation system. A general model was proposed to quantify the nature of input-output relation of the cotton crop. A proposed simplified model based on stem diameter is also introduced. The stem diameter measurements can be used as an index for estimation of cotton's water content, transpiration rate, and water potential. These three parameters and the proposed simplified model established a plant based predictive irrigation scheduling technique. The electrical output of the LVDT was quite noisy. To remove the noise and demodulate the data, two cascade circuits were designed and implemented. First, the external output circuit removed the noise and isolated the LVDT. Second, the LVDT signal conditioner demodulated the phase information from the secondary windings which were produced by the movement of the rod. By the implementation of these circuits, 1 m of the rod displacement resulted in 1.14 mv of dc voltage changes in the output.
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Juve, John A. "Assessing differential item functioning and item parameter drift in the college basic academic subjects examination /." free to MU campus, to others for purchase, 2004. http://wwwlib.umi.com/cr/mo/fullcit?p3137717.
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Bunyaraksh, S. S. "Relation between dyeability of polyester yarn and its structure : Studied by density measurements and differential scanning calorimetry." Thesis, University of Leeds, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.379540.
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Tan, Jun. "Analysis and application of differential propagation phase shift in polarization-diversity radar measurements of precipitation at centimeter wavelengths." Thesis, University of Essex, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.303477.
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Watson, Ian. "Differential top pair production cross-section measurements at √(s) = 7 TeV with the ATLAS detector at the LHC." Thesis, The University of Sydney, 2014. http://hdl.handle.net/2123/11929.
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The top quark is the most massive fundamental particle of the Standard Model of particle physics, and as the only quark to decay before hadronising gives a unique opportunity for studying QCD, the theory of the strong interaction. In this thesis, we study the \ttbar production cross-section as a function of several variables related to the produced top quarks. This thesis presents variables defined after the hadronisation of the top quark, and so are mostly independent of its theoretical description, unlike previous results which are corrected to the partonic variables. Using the ATLAS detector at the LHC, the measurements are performed for √(s) = 7 TeV proton-proton collisions. The measurements are sensitive to various parameters entering the description of top quark production, including the Parton Distribution Functions, and so have good potential to be used in furthering our understanding of proton collision physics and for future tunings of the models used in describing the physics.
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Wang, Shengan. "A New Approach to the Optimal Filtering of Differential Phase Measurements of GPS Signal in the Precision Survey." PDXScholar, 1993. https://pdxscholar.library.pdx.edu/open_access_etds/4633.
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The Global Positioning System (GPS) has become popular research and application interests in surveying and many other areas. Nowadays, the accuracy of the Differential GPS can easily reach the order of a few meters. Yet, there are still many ways to exploit the GPS system signal carrier to improve the accuracy to less than meter level. In this thesis, a new approach to improve the accuracy to less than meter level is presented while the observer is in the dynamic situation. In order to reach the sub-meter accuracy, we measure on the carrier phase difference (The L1 carrier frequency is 1575.42 Mhz, 1=19 em) between a reference point A and a primary point B. This actually means we work on the accuracy of centimeter. In this proposed method of the precision survey, first the Differential GPS is used to fix the position in the accuracy of meter level, and then by measuring the signal carrier relative difference we can work on the accuracy in the accuracy level of the wavelength (19 cm). The measuring on the relative carrier phase will introduce the problem of initial modulo 2π phase (integer wavelength) ambiguity. To solve the initial integer ambiguity, A Multiple Model Estimation Algorithm (MMEA) which was developed by D.T. Magill in 1965 is applied. The MMEA is composed of a bank of parallel Kalman filters, all operating on the input measurement sequence simultaneously. Each filter in the bank of filters is modeled around a different hypothesis. The number of the required parallel filters is the number of hypothesis of integer ambiguity which is determined by the error range of the differential phase measurement. And the error range of the differential phase measurement is related to the accuracy of the Differential GPS. The precision positioning by MMEA method has some advantage compares with other methods now being used . . It does not require continuous observation of the satellites initially. . Kalman filter is recursive technique. So it has the potential of on-line . . Kalman filter is widely used in navigation and approved to be very efficient and versatile. Computer simulation results are given for a hypothetical GPS system. They demonstrate that the MMEA can effectively solve the integer wavelength ambiguity problem in dynamic situation. The simulation results presented are especially encouraging with regard to the flexibility and efficiency in precision survey. A further improvement of precision surveying by GPS is also discussed in the last Chapter. By using Markov Model and Verterbi Algorithm, a more flexible and reliable precision surveying method could be available.
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Scaini, Denis. "Electrical characterization of organic monolayers at the nanoscale: a differential scanning conductive tip AFM investigation." Doctoral thesis, Università degli studi di Trieste, 2008. http://hdl.handle.net/10077/2609.
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2006/2007CT-AFM (Conductive Tip AFM) is commonly used for electrical characterization of organic and inorganic surface systems. Understanding electron transfer at the molecular level may lead to the development of molecular assemblies with unique properties and is of great importance for the advancement of both organic, molecular and bio-electronics. In this work we follow an approach to the study of Metal-molecule-Metal surface junctions that uses a combination of different AFM-based techniques. We first use nanografting to build nanopatches of the molecules of interest into a hosting reference self assembled monolayer (SAM) typically made of alkane and aromatic thiols. After the tip is changed to a conductive one, CT-AFM is used to characterize electrically the whole system recording, at the same time, the system topography. Some of the advantages of this approach are the possibility to build and study a wide range of different monolayers side-by-side on the same sample and the in-situ control of the quality both of the hosting monolayer and that of the grafted patches. Results will be presented on saturated and unsaturated thiols self-assembled and nanografted on Au(111) surfaces. We will also show a clear correlation between the contrast in current images and the quality of molecular packing inside the nanopatches.
XX Ciclo
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Shim, Hi Shin. "An irt model to estimate differential latent change trajectories in a multi-stage, longitudinal assessment." Thesis, Atlanta, Ga. : Georgia Institute of Technology, 2009. http://hdl.handle.net/1853/28266.
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Zou, Weiyao. "OPTIMIZATION OF ZONAL WAVEFRONT ESTIMATION AND CURVATURE MEASUREMENTS." Doctoral diss., University of Central Florida, 2007. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/4134.
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Optical testing in adverse environments, ophthalmology and applications where characterization by curvature is leveraged all have a common goal: accurately estimate wavefront shape. This dissertation investigates wavefront sensing techniques as applied to optical testing based on gradient and curvature measurements. Wavefront sensing involves the ability to accurately estimate shape over any aperture geometry, which requires establishing a sampling grid and estimation scheme, quantifying estimation errors caused by measurement noise propagation, and designing an instrument with sufficient accuracy and sensitivity for the application. Starting with gradient-based wavefront sensing, a zonal least-squares wavefront estimation algorithm for any irregular pupil shape and size is presented, for which the normal matrix equation sets share a pre-defined matrix. A Gerchberg–Saxton iterative method is employed to reduce the deviation errors in the estimated wavefront caused by the pre-defined matrix across discontinuous boundary. The results show that the RMS deviation error of the estimated wavefront from the original wavefront can be less than λ/130~ λ/150 (for λ equals 632.8nm) after about twelve iterations and less than λ/100 after as few as four iterations. The presented approach to handling irregular pupil shapes applies equally well to wavefront estimation from curvature data. A defining characteristic for a wavefront estimation algorithm is its error propagation behavior. The error propagation coefficient can be formulated as a function of the eigenvalues of the wavefront estimation-related matrices, and such functions are established for each of the basic estimation geometries (i.e. Fried, Hudgin and Southwell) with a serial numbering scheme, where a square sampling grid array is sequentially indexed row by row. The results show that with the wavefront piston-value fixed, the odd-number grid sizes yield lower error propagation than the even-number grid sizes for all geometries. The Fried geometry either allows sub-sized wavefront estimations within the testing domain or yields a two-rank deficient estimation matrix over the full aperture; but the latter usually suffers from high error propagation and the waffle mode problem. Hudgin geometry offers an error propagator between those of the Southwell and the Fried geometries. For both wavefront gradient-based and wavefront difference-based estimations, the Southwell geometry is shown to offer the lowest error propagation with the minimum-norm least-squares solution. Noll's theoretical result, which was extensively used as a reference in the previous literature for error propagation estimate, corresponds to the Southwell geometry with an odd-number grid size. For curvature-based wavefront sensing, a concept for a differential Shack-Hartmann (DSH) curvature sensor is proposed. This curvature sensor is derived from the basic Shack-Hartmann sensor with the collimated beam split into three output channels, along each of which a lenslet array is located. Three Hartmann grid arrays are generated by three lenslet arrays. Two of the lenslets shear in two perpendicular directions relative to the third one. By quantitatively comparing the Shack-Hartmann grid coordinates of the three channels, the differentials of the wavefront slope at each Shack-Hartmann grid point can be obtained, so the Laplacian curvatures and twist terms will be available. The acquisition of the twist terms using a Hartmann-based sensor allows us to uniquely determine the principal curvatures and directions more accurately than prior methods. Measurement of local curvatures as opposed to slopes is unique because curvature is intrinsic to the wavefront under test, and it is an absolute as opposed to a relative measurement. A zonal least-squares-based wavefront estimation algorithm was developed to estimate the wavefront shape from the Laplacian curvature data, and validated. An implementation of the DSH curvature sensor is proposed and an experimental system for this implementation was initiated. The DSH curvature sensor shares the important features of both the Shack-Hartmann slope sensor and Roddier's curvature sensor. It is a two-dimensional parallel curvature sensor. Because it is a curvature sensor, it provides absolute measurements which are thus insensitive to vibrations, tip/tilts, and whole body movements. Because it is a two-dimensional sensor, it does not suffer from other sources of errors, such as scanning noise. Combined with sufficient sampling and a zonal wavefront estimation algorithm, both low and mid frequencies of the wavefront may be recovered. Notice that the DSH curvature sensor operates at the pupil of the system under test, therefore the difficulty associated with operation close to the caustic zone is avoided. Finally, the DSH-curvature-sensor-based wavefront estimation does not suffer from the 2-ambiguity problem, so potentially both small and large aberrations may be measured.Ph.D.
Optics and Photonics
Optics and Photonics
Optics PhD
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Aad, G., Richard Brenner, Claus P. Buszello, Tord Ekelöf, Mattias Ellert, Arnaud Ferrari, Charlie Isaksson, Daniel Pelikan, and L. Zwalinski. "Measurements of top quark pair relative differential cross-sections with ATLAS in pp collisions at root s=7 TeV." Uppsala universitet, Högenergifysik, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-201934.
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Measurements are presented of differential cross-sections for top quark pair production in pp collisions at root s = 7 TeV relative to the total inclusive top quark pair production cross-section. A data sample of 2.05 fb(-1) recorded by the ATLAS detector at the Large Hadron Collider is used. Relative differential cross-sections are derived as a function of the invariant mass, the transverse momentum and the rapidity of the top quark pair system. Events are selected in the lepton (electron or muon) + jets channel. The background-subtracted differential distributions are corrected for detector effects, normalized to the total inclusive top quark pair production cross-section and compared to theoretical predictions. The measurement uncertainties range typically between 10 % and 20 % and are generally dominated by systematic effects. No significant deviations from the Standard Model expectations are observed.ATLAS Collaboration, for complete list of authors see http://dx.doi.org/10.1140/epjc/s10052-012-2261-1
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Chembil, Palat Ramesh. "VT-STAR design and implementation of a test bed for differential space-time block coding and MIMO channel measurements." Thesis, Virginia Tech, 2002. http://hdl.handle.net/10919/35712.
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Next generation wireless communications require transmission of reliable high data rate services. Second generation wireless communications systems use single-input multiple-output (SIMO) channel in the reverse link, meaning one transmit antenna at the user terminal and multiple receive antennas at the base station. Recently, information theoretic research has shown an enormous potential growth in the capacity of wireless systems by using multiple antenna arrays at both ends of the link. Space-time coding exploits the spatial-temporal diversity provided by the multiple input multiple output (MIMO) channels, significantly increasing both system capacity and the reliability of the wireless link. The Virginia Tech Space-Time Advanced Radio (VT-STAR) system presents a test bed to demonstrate the capabilities of space-time coding techniques in real-time. Core algorithms are implemented on Texas Instruments TMS320C67 Evaluation Modules (EVM). The radio frequency subsystem is composed of multi-channel transmitter and receiver chains implemented in hardware for over the air transmission. The capabilities of the MIMO channel are demonstrated in a non-line of sight (NLOS) indoor environment. Also to characterize the capacity gains in an indoor environment this test bed was modified to take channel measurements. This thesis reports the system design of VT-STAR and the channel capacity gains observed in an indoor environment for MIMO channels.Master of Science
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Spannagel, Simon [Verfasser], and Erika [Akademischer Betreuer] Garutti. "Test Beam Measurements for the Upgrade of the CMS Pixel Detector and Measurement of the Top Quark Mass from Differential Cross Sections / Simon Spannagel. Betreuer: Erika Garutti." Hamburg : Staats- und Universitätsbibliothek Hamburg, 2016. http://d-nb.info/1103233351/34.
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Cuppini, Elena. "Determination of the top-quark mass using top-antitop cross section measurements at LHC." Bachelor's thesis, Alma Mater Studiorum - Università di Bologna, 2021. http://amslaurea.unibo.it/23715/.
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Lo studio della fisica del quark top rappresenta un campo in continuo sviluppo da partedella comunità teorica ed è di grande interesse all’interno del programma di fisica sperimentale ad ATLAS. In questa tesi, la massa del quark top è estratta mediante il confronto di calcoli di QCD della sezione d’urto totale e differenziale della produzione top-antitop in collisioni protone-protone ad energia del centro di massa di √s= 13 TeV, prodotti con il programma MATRIX al next-to-next-to-leading order, con dati sperimentali da collisioni pp a √s= 13 TeV raccolti nel 2015 e nel 2016 dal detector ATLAS al Large Hadron Collider (LHC) del CERN, corrispondenti a una luminosità integrata di 36.1 fb−1. Utilizzando la sezione d’urto totale top-antitop (t ̄t) misurata in eventi dileptonicieμe conducendo un’analisi basata su un approccio Bayesiano che utilizza Markov Chain Monte Carlo (MCMC), il valore ottenuto per la massa del quark top è m_t=(174.4+1.7−2.7) GeV. Dal confronto delle predizioni teoriche per la sezione d’urto differenziale assoluta in funzione della massa invariante (m_t ̄t) con dati misurati nel canale leptoni + jet a livello partonico, una seconda estrazione della massa del quark top ha portato al valore m_t= (171.9+3.0−2.9) GeV, ottenuto analizzando il χ2 tra i valori della predizione e quelli misurati.
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Rumburg, Brian Paul. "Differential optical absorption spectroscopy (DOAS) measurements of atmospheric ammonia in the mid-ultraviolet from a dairy concentrations, emissions, and modeling /." Online access for everyone, 2006. http://www.dissertations.wsu.edu/Dissertations/Spring2006/b%5Frumburg%5F031006.pdf.
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Levy, Mark. "Inclusive and differential measurements of spin correlation in top-antitop quark pairs at √s = 8 TeV using the ATLAS detector." Thesis, University of Birmingham, 2016. http://etheses.bham.ac.uk//id/eprint/6995/.
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A measurement of the spin correlation strength in top-antitop pairs is presented, using protonproton collision data collected at the ATLAS detector with a centre of mass energy of √s = 8 TeV and an integrated luminosity of 20.3 fb\(^{-1}\). An inclusive measurement is made, as well as a differential measurement as a function of the top-antitop invariant mass. Additionally, these measurements are made both at detector level and unfolded to a parton level distribution. Selected events are required to have exactly two oppositely charged leptons (either electrons or muons), a large missing transverse energy and at least two hadronic jets, at least one of which must be tagged as originating from a b-quark. The azimuthal separation between the two charged leptons, Δφ, is used to measure the degree of spin correlation. The measured distribution is compared to a Standard Model prediction and a model with no spin correlation. It is found that the results all favour the Standard Model prediction over the uncorrelated model, with the data found to be several standard deviations away from the uncorrelated scenario.
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Liu, Mingyang Liu. "Differential Item Functioning in Large-scale Mathematics Assessments: Comparing the Capabilities of the Rasch Trees Model to Traditional Approaches." University of Toledo / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1513266587329066.
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Bieniek, S. P. "Two b or not two b-jets : measurements of inclusive and dijet b-jet differential cross-sections with the ATLAS detector." Thesis, University College London (University of London), 2013. http://discovery.ucl.ac.uk/1410936/.
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This thesis discusses the measurement of the inclusive b-jet cross-section using the 2010 ATLAS dataset and the measurement of di-b-jet cross-sections using the 2011 dataset. The inclusive b-jet analysis measured the pT spectrum of b-jets in the range 20
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Glaysher, Paul Christopher Frederick. "Differential cross section measurements in H→ WW and prospects of observing H→ bb in future LHC runs at the ATLAS detector." Thesis, University of Edinburgh, 2016. http://hdl.handle.net/1842/22074.
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The highly celebrated discovery of a new particle with a mass of 125 GeV in proton-proton collisions by the ATLAS and CMS experiments at the CERN Large Hadron Collider in 2012 has been shown to be compatible with the Standard Model description of the Higgs boson. However, in order to fully verify the Standard Model nature of the Higgs boson, most of its properties still remain to be measured. Such measurements include differential cross section measurements, which are shown here for the H→WW decay channel and the coupling of the Higgs boson to bottom quarks, for which a study of future prospects is presented. Differential fiducial cross section measurements of the Higgs boson were performed in the H → WW*→lvlv channel at the ATLAS detector with 20 fb−1 of √s = 8 TeV collision data. For Higgs bosons produced by gluon-gluon fusion, the cross section is measured as a function of kinematic variables, including transverse momentum and rapidity of the Higgs boson, as well as the number of jets associated with the Higgs event. The obtained distributions are unfolded to a fiducial volume using a two-dimensional iterative Bayesian algorithm. The measured fiducial differential cross sections are compared to predictions from Monte Carlo generators. The total cross section measured in the fiducial volume defined by the charged lepton and neutrino kinematic properties is 36.0 ± 9.7 fb. Additionally the jet-veto efficiency in the fiducial volume is extracted from the differential cross sections. An analysis is presented of Higgs boson production and decay into bottom quarks in association with a vector boson at the ATLAS detector for the future high-luminosity LHC with proton-proton collisions at √s = 14 TeV. The vector bosons are reconstructed from Z→l+l− or W→lv final states, where l is an electron or muon. The analysis uses generator-level Monte Carlo samples to which efficiency and resolution smearing functions are applied. These reproduce the expected resolution of the upgraded ATLAS detector for the foreseen amount of pile-up due to multiple overlapping proton-proton collisions. The analysis of the ZH(→ l+l−b¯b) channel is presented and results are combined with the WH(→lvb¯b) channel from a corresponding study. For an integrated luminosity of 300 fb−1 using an average pile-up of 60, the expected significance is 3.9 σ with an expected error on the signal strength of 25%. Likewise, for 3000 fb−1 using an average pileup of 140 the expected significance is 8.8 σ , and the error on the signal strength is expected to be about 15%.
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Franchini, Matteo <1986>. "Measurements of ttbar Differential Cross Section at the ATLAS Experiment in pp Collisions at sqrt(s)=7TeV and sqrt(s)=8TeV." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2014. http://amsdottorato.unibo.it/6231/1/franchini_matteo_tesi.pdf.
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This PhD thesis presents two measurements of differential production cross section of top and anti-top pairs tt ̅ decaying in a lepton+jets final state. The normalize cross section is measured as a function of the top transverse momentum and the tt ̅ mass, transverse momentum and rapidity using the full 2011 proton-proton (pp) ATLAS data taking at a center of mass energy of √s=7 TeV and corresponding to an integrated luminosity of L=4.6 〖fb〗^(-1). The cross section is also measured at the particle level as a function of the hadronic top transverse momentum for highly energetic events using the full 2012 data taking at √s=8 TeV and with L=20 〖fb〗^(-1). The measured spectra are fully corrected for detector efficiency and resolution effects and are compared to several theoretical predictions showing a quite good agreement, depending on different spectra.
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Franchini, Matteo <1986>. "Measurements of ttbar Differential Cross Section at the ATLAS Experiment in pp Collisions at sqrt(s)=7TeV and sqrt(s)=8TeV." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2014. http://amsdottorato.unibo.it/6231/.
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This PhD thesis presents two measurements of differential production cross section of top and anti-top pairs tt ̅ decaying in a lepton+jets final state. The normalize cross section is measured as a function of the top transverse momentum and the tt ̅ mass, transverse momentum and rapidity using the full 2011 proton-proton (pp) ATLAS data taking at a center of mass energy of √s=7 TeV and corresponding to an integrated luminosity of L=4.6 〖fb〗^(-1). The cross section is also measured at the particle level as a function of the hadronic top transverse momentum for highly energetic events using the full 2012 data taking at √s=8 TeV and with L=20 〖fb〗^(-1). The measured spectra are fully corrected for detector efficiency and resolution effects and are compared to several theoretical predictions showing a quite good agreement, depending on different spectra.
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Chauhan, Kripa Nidhan. "Carrier Dynamics in InGaAs/GaAs Quantum Dots Excited by Femtosecond Laser Pulses." DigitalCommons@USU, 2013. https://digitalcommons.usu.edu/etd/1467.
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Ultrafast carrier dynamics studies have been carried out on samples with single layers of self-assembled In0.4Ga0.6As/GaAs quantum dots (QDs). Measurements were made using femtosecond degenerate pump-probe differential reflectivity with an 800-nm, 28-fs Ti-sapphire oscillator as the source. The QDs were grown via modified Stranski-Krastanov growth. This modified growth process consists of two steps: low-temperature growth and high-temperature annealing. Specifically, the InGaAs QD structures are fabricated on n-type GaAs(001) using molecular beam epitaxy. The InGaAs layer is deposited at 350-3700C followed by QD self assembly at 420-4900C. Finally, these QDs are capped with 10 nm or 100 nm of GaAs. The measured width and height of these QDs are typically 25 nm and 8 nm, respectively. Dots annealed at higher temperature have larger base area (width and length) and reduced height, as compared to those annealed at lower temperature. We have used a model consisting of a linear combination of an exponential decaying function to describe the carrier dynamics and fit the reflectivity data, revealing trends in the carrier capture and relaxation times associated with the InGaAs layer versus laser excitation level and QD morphology. Capture times are ~ 1 ps for the 100-nm capped samples, but slightly shorter for the 10-nm capped thin samples, indicating carrier transport plays a role in dynamics. The carrier dynamics in 10-nm capped samples are correlated with sample annealing temperature, indicating QD morphology affects carrier capture. Versus laser intensity, and thus carrier excitation level, the dynamics generally become slower, suggesting state filling is important in both the capture and relaxation of excited carriers in these samples.
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Zhang, Rui [Verfasser]. "Inclusive and differential cross-section measurements of tW single top-quark production at √s = 13 TeV with the ATLAS detector / Rui Zhang." Bonn : Universitäts- und Landesbibliothek Bonn, 2019. http://d-nb.info/1191832031/34.
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Lilley, Joseph Neil. "Z + γ differential cross section measurements and the digital timing calibration of the level-1 calorimeter trigger cluster processor system in ATLAS." Thesis, University of Birmingham, 2011. http://etheses.bham.ac.uk//id/eprint/1612/.
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This thesis investigates the reconstruction of Z(→ee)γ events with the ATLAS detector at the LHC. The capabilities of the detector are explored for the initial run scenario with a proton-proton centre of mass collision energy of √s = 7TeV, and an integrated luminosity of \(\char{cmsy10}{0x4C}\) = 1 fb⁻¹. Monte Carlo simulations are used to predict the expected precision of a differential cross-section measurement for initial state radiation Z + γ events, both with respect to the transverse momentum of the photon, p_T(γ), and the three body eeγ invariant mass. A bin-by-bin correction is used to account for the signal selection efficiency and purity, and to correct the measured (simulated) distribution back to the theoretical prediction. The main backgrounds are found to be from the final state radiation Z + γ process, and from jets faking photons in Z → ee events. The possible QCD multijet background is studied using a fake-rate method, and found to be negligible for the particle identification cuts used in the analysis. The main systematic uncertainties on the differential cross-section measurements are explored with Monte Carlo simulations, and found to be of a similar scale to the statistical errors for the chosen distribution binning. The three body eeγ invariant mass distribution was then used as the basis of an exclusion study on new particles decaying to the Z(ee)γ final state. Under the assumption that the measured data agrees with the Standard Model prediction, exclusion limits were placed at 95% confidence level on the cross-section times branching ratio for a new scalar (modelled by SM Higgs process), or vector (based on a low-scale technicolor process) particle hypothesis, for particles in the mass range 200 to 900GeV. Limits of the order \(\char{cmsy10}{0x4f}\)(0.01) - \(\char{cmsy10}{0x4f}\)(0.1) pb on the cross section times branching ratios are predicted, which would improve on the equivalent limits previously calculated by the DØ experiment at the Tevatron collider, albeit in a different √s region, where cross-sections will generally be higher for new massive particles. In addition to the Zγ measurements, a digital timing calibration procedure was developed for the Cluster Processor (CP) subsystem of the level-1 calorimeter trigger. This work was essential to providing a repeatable and robust mechanism for timing in the digital processing in the CP system, a necessary ingredient for a robust and reliable trigger system; a pre-requisite of any physics analysis. This calibration procedure is described here.
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Driana, Elin. "GENDER DIFFERENTIAL ITEM FUNCTIONING ON A NINTH-GRADE MATHEMATICS PROFICIENCY TEST IN APPALACHIAN OHIO." Ohio University / OhioLINK, 2007. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1181693190.
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Zhao, Jing. "Contextual Differential Item Functioning: Examining the Validity of Teaching Self-Efficacy Instruments Using Hierarchical Generalized Linear Modeling." The Ohio State University, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=osu1339551861.
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Johansson, Cecilia. "High-sensitivity Radioactive Xenon Monitoring and High-accuracy Neutron-proton Scattering Measurements." Doctoral thesis, Uppsala : Acta Universitatis Upsaliensis : Univ.-bibl. [distributör], 2004. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-4279.
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