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Description
In electric power systems, phasor measurement units (PMUs) are capable of providing synchronized voltage and current phasor measurements which are superior to conventional measurements collected by the supervisory control and data acquisition (SCADA) system in terms of resolution and accuracy. These measurements are known as synchrophasor measurements. Considerable research work

In electric power systems, phasor measurement units (PMUs) are capable of providing synchronized voltage and current phasor measurements which are superior to conventional measurements collected by the supervisory control and data acquisition (SCADA) system in terms of resolution and accuracy. These measurements are known as synchrophasor measurements. Considerable research work has been done on the applications of PMU measurements based on the as-sumption that a high level of accuracy is obtained in the field. The study in this dissertation is conducted to address the basic issue concerning the accuracy of actual PMU measurements in the field. Synchronization is one of the important features of PMU measurements. However, the study presented in this dissertation reveals that the problem of faulty synchronization between measurements with the same time stamps from different PMUs exists. A Kalman filter model is proposed to analyze and calcu-late the time skew error caused by faulty synchronization. In order to achieve a high level of accuracy of PMU measurements, inno-vative methods are proposed to detect and identify system state changes or bad data which are reflected by changes in the measurements. This procedure is ap-plied as a key step in adaptive Kalman filtering of PMU measurements to over-come the insensitivity of a conventional Kalman filter. Calibration of PMU measurements is implemented in specific PMU instal-lation scenarios using transmission line (TL) parameters from operation planning data. The voltage and current correction factors calculated from the calibration procedure indicate the possible errors in PMU measurements. Correction factors can be applied in on-line calibration of PMU measurements. A study is conducted to address an important issue when integrating PMU measurements into state estimation. The reporting rate of PMU measurements is much higher than that of the measurements collected by the SCADA. The ques-tion of how to buffer PMU measurements is raised. The impact of PMU meas-urement buffer length on state estimation is discussed. A method based on hy-pothesis testing is proposed to determine the optimal buffer length of PMU meas-urements considering the two conflicting features of PMU measurements, i. e. un-certainty and variability. Results are presented for actual PMU synchrophasor measurements.
ContributorsZhang, Qing (Author) / Heydt, Gerald (Thesis advisor) / Vittal, Vijay (Thesis advisor) / Ayyanar, Raja (Committee member) / Si, Jennie (Committee member) / Arizona State University (Publisher)
Created2012
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Description
A great deal of contemporary research argues that humans learn from experience. This research, however, rarely explicates what constitutes an experience for humans, let alone experiences that lead to deep learning for human flourishing. Experience is constituted of inner and out sensations processed in certain ways. Thus, a biologically realistic

A great deal of contemporary research argues that humans learn from experience. This research, however, rarely explicates what constitutes an experience for humans, let alone experiences that lead to deep learning for human flourishing. Experience is constituted of inner and out sensations processed in certain ways. Thus, a biologically realistic theory of learning must be based on a theory of sensation and how sense making derives from sensation. This dissertation seeks such a theory in the emerging literature on what kinds of creatures humans are and what this implies about how they learn and flourish. This literature ranges across several different disciplines, including neuroscience, evolutionary biology, and work on how affect guides cognition and action. Humans are as able to learn from experiences they have had in media as they are from experiences they have had in the real world. In either case, however, humans do not learn deeply from random experiences. They learn best from experiences that have been designed to recruit affect, help them manage their attention, and give them ways to assess the success of actions they take toward goals. Thus, teaching in the sense of experience design—a task for teachers in schools, as well as media designers and artists of all different sorts—is fundamental to human learning and flourishing. The dissertation defines flourishing in terms of the state of a human being’s allostatic load, a variable which can be measured. Since I am interested how experience designers design sensation to create sense making and sense making that can enhance human flourishing, I am interest in experience design in the arts, a domain that has traditionally been seen as an important source of insight built on sensation. I use examples from traditional and contemporary art in the dissertation. The last chapter is an extended study of the anime Attack on Titan I show how the design of Attack on Titan uses sensation to engender deep contemplation and discussion of complex political, historical, and philosophical issues. The way it achieves this goal has important implications for teaching and learning in and out of school.
ContributorsZhang, Qing (Author) / Gee, James P (Thesis advisor) / Gee, Elisabeth R (Thesis advisor) / Glenberg, Arthur M (Committee member) / Arizona State University (Publisher)
Created2022