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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
71

The Enchantment of Ethics: Empathy, Character, and the Art of Moral Living

Parzuchowski, Kimberley 23 February 2016 (has links)
My dissertation explores the role of narrative in the cultivation of empathy for ethical attitudes and behaviors. I begin by exploring an uncommon view of human nature, concluding that we are not autonomously individualistic rational deciders but ultrasocial moral intuitionists. Our intuitions are developed through our social engagements and the moral imagination. Intersubjective relations run deep in our psychology and provide the basis by which we shape the meaning of our lives as individuals in communities. It is because of this that we need to reconsider and redesign our moral cultivation programs both for the child-rearing years and throughout adult life. I look at empathy, the means of our mutual understanding, care, and help, as a key site for moral cultivation. I explicate the neurophysiological bases of empathy, both conscious and unconscious. Empathy is on the continuum with very primitive, automatic mirroring systems, which through varying levels of mimicry facilitate social cognition and moral insight and action. It is thus the ideal means of cultivating a skillful morality. Empathy enables us to enter the worlds and feelings of others in rich and full-bodied ways and so can reveal others in their full subjectivity. Such experiences can incite empathic regard and compassionate action, but empathy, like all of our psycho-social capacities, requires cultivation to develop its skillfulness in practice. Narrative is an obvious means of cultivating empathy because it is humanity’s primary meaning-making structure, utilizing the empathic imagination to seduce us into the inner worlds of others. Through narrative dramatizations of experience, we learn to see and feel from another’s point of view, sensitizing us to their inner states and outward behavior. Such sensitivity can facilitate improving our moral attitudes and action by dislodging preoccupation with self-concern and instigating higher regard for others. In narratives we can imaginatively practice various moral actions, witnessing possible results. Reflective engagement can then bring the moral insights of these imaginative experiences to life in our practical worlds by attuning us to what is morally salient. Narrative engagement is thus a natural and vital part of shaping empathic moral perception for compassionate action. By reading and feeling with others reflectively, we can expand empathy for the pluralistic communities in which we live, make meaning, and grow.
72

SYZ mirror symmetry for toric Calabi-Yau manifolds. / CUHK electronic theses & dissertations collection

January 2011 (has links)
It is conjectured that the SYZ map equals to the inverse mirror map. In dimension two this conjecture is proved, and in dimension three supporting evidences of the equality are studied in various examples. Since the SYZ map is expressed in terms of open Gromov-Witten invariants, this conjectural equality established an enumerative meaning of the inverse mirror map. / Moreover a computational method of open Gromov-Witten invariants for toric Calabi-Yau manifolds is invented. As an application, the Landau-Ginzburg mirrors of compact semi-Fano toric surfaces are computed explicitly. / This thesis gives a procedure to carry out SYZ construction of mirrors with quantum corrections by Fourier transform of open Gromov-Witten invariants. Applying to toric Calabi-Yau manifolds, one obtains the Hori-Iqbel-Vafa mirror together with a map from the Kahler moduli to the complex moduli of the mirror, called the SYZ map. / Lau, Siu Cheong. / Adviser: N.C. Leung. / Source: Dissertation Abstracts International, Volume: 73-06, Section: B, page: . / Thesis (Ph.D.)--Chinese University of Hong Kong, 2011. / Includes bibliographical references (leaves 143-148). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [201-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese.
73

Porous silicon multilayers for gigahertz bulk acoustic wave devices

Thomas, Leigh-Anne January 2011 (has links)
Acoustic filters for signal filtering are used in wireless technologies operating at gigahertz frequencies for communication systems such as next generation cell phones. Multilayered porous silicon structures have been fabricated from silicon wafers to create the Bragg mirror section of a bulk acoustic wave filter. These porous silicon multilayers have been designed for use from 500 MHz – 20 GHz with primary focus on frequencies at 1 GHz. The porous silicon multilayers consist of alternating layers of high and low acoustic impedance layers on a bulk silicon substrate. They are fabricated using electrochemical etching where the current density during the etch determines the porosity and hence acoustic impedance of each layer. Bragg mirrors, FabryPerot filters, microcavities and rugate filters can be produced in this way due to the control of the tuneable porosity profile throughout the structure. The porosity of the layer modifies the elastic constants of the layer such as the Young’s modulus and hence the velocity of the bulk acoustic waves travelling through it. The behaviour of bulk acoustic waves through silicon is known but in order to fabricate porous silicon acoustic filters, the dependence of the longitudinal wave velocity as a function of porosity must also be known. This has been studied using acoustic transmission measurements on single porous silicon layers and then extended to multilayered structures. Rugate filters are single frequency filters that have not previously been studied for acoustic applications. In this study the first acoustic rugate filters have been fabricated using porous silicon material that exhibit only one stopband near 1 GHz. Bragg mirrors have been made with acoustic transmission measurements showing the locations of the stopbands. Porous silicon microcavities have also been fabricated along with filters that have apodisation functions. This work could form the basis of future efforts to produce and incorporate allSi multilayers into acoustic filters that are easily fabricated at a high level of quality and reliability that will serve to be efficient and cost effective.
74

High voltage, high resolution, digital-to-analog converter for driving deformable mirrors

Kittredge, Jeffrey Prax 12 March 2016 (has links)
Digital-to-analog converters with a range over 50 volts are required for driving micro-electro mechanical system deformable mirrors used in adaptive optics. An existing tested and deployed DM driver has 1024 channels and resolution of 15mV per Least Significant Bit. DMs used in the search for exoplanets require 3mV per LSB resolution. A technique is presented to employ a secondary high resolution and low voltage DAC which has for it's ground the output of the high voltage DAC. The entire system then has the range of high voltage DAC yet the resolution of the low voltage DAC. A method for providing signal and power to the floating system is given. Rudimentary micro controller firmware and also PC software is presented to achieve complete functionality. The technique uses all off-the-shelf components. Resolution of 1.6mV per LSB, 60V range and 36mW of power per channel is achieved.
75

Theory and Poetry: John Ashbery's "Self-portrait in a Convex Mirror"

Timmons, Jeffrey Wayne 20 May 1994 (has links)
This thesis examines John Ashbery's poem "Self-Portrait in a Convex Mirror" and its revision of the traditional distinction between theory and poetry. Drawing a relationship between the poem's subject and the practices of postmodern theoretical discourse, the thesis posits the poem as an artifact of these changes. Creating a context for the poem, these developments not only inform the climate in which Ashbery's poem takes on significance, but, as well, explain the changing nature of literary study. Historical in its approach to the pressures and impulses within this climate of aesthetic production, the thesis traces the distinction between science and literature and how it has influenced the creation of the literary discipline. Demonstrating that the disciplinary study of literature has always been the subject of debate and discussion, it uses this understanding to place present disagreements about the need or usefulness of theory in the context of historical disagreements over the difference of literature from science or philosophy. Explaining that postmodern theory has largely worked to foreground the arbitrary nature of distinctions such as that between theory and poetry, the thesis elaborates on how poststructuralism undoes these distinctions to show how they are always the result of particular political and ideological views of representation. Using this critical insight, the thesis then reads closely the details of the poem's relationship to postmodern theory, how it works to undo the distinction between theory and poetry. Having undone this traditional distinction, however, leaves the poem in an ambivalent and unstable position. Since it passes between extant categorical definitions its own nature remains undecided and, thus, maintains an engagement with and resistance to tradition. It remains caught between the need for the aesthetic past and the need for a freedom from that past. Chapter four, therefore, explores this ambivalence, particularly as it relates to the inheritance of romanticism and modernism. Finally, in chapter five, the thesis revises the main critical perception of Ashbery as postmodern, making a case for his closer affiliation with a late version of modernism. Because of Ashbery's preoccupation with the aesthetic past, his use of the imagery, insights, and idealism of our aesthetic history, he appears to re-create a distinction between high and popular art that is more consonant with a version of modernism.
76

A convergent beam electron diffraction study of some rare-earth perovskite oxides

Jones, Daniel M. January 2008 (has links)
This work describes detailed convergent beam electron diffraction (CBED) studies of GdAlO3 and LaAlO3 perovskites. CBED patterns tilted away from major zone axes have been found to have high sensitivity to the presence of mirror or glide mirror symmetry. Such patterns confirm to high accuracy that the space group of GdAlO3 is orthorhombic, Pnma. Tilted patterns from this well characterised structure also serve as benchmarks against which similar patterns may be compared. In the case of LaAlO3, tilted patterns enable the space group to be confirmed as rhombohedral R3c, previously claimed to be cubic (Fm3c) by CBED. Furthermore, no evidence for the low symmetry (I2/a or F1) phases proposed for LaAlO3 has been observed. The LaAlO3 study also gives a careful assessment of the influence of tilted specimen surfaces on the CBED data. Within the qualitative scope of these experiments, no symmetry degrading effects could be observed. Some preliminary Quantitative CBED (QCBED) data from LaAlO3 is also presented. This shows it will be possible to make a detailed study of the bonding charge density (Δρ) in this material when combined with X-ray diffraction data. Also included is a brief CBED study of LaFeO3, a material that is isostructural with GdAlO3. Although this is restricted to exact zone axis patterns, it is noted that tilted patterns have significant potential to improve the quality of the symmetry determination.
77

From Motion to Movements : Revelations by the Infant EEG

Nyström, Pär January 2008 (has links)
The introduction of high density EEG (hd-EEG) nets for easy application on subjects of all ages has improved the possibilities to investigate the development of the infant neurophysiology. This dissertation consists of three studies (I – III) that investigate the visual motion system and mirror neuron system of the infant, and methodological sections that outline the bioelectrical background and the characteristics of the methods used. Study I covers the maturation of cortical areas involved in motion perception in adults and infants using an ERP paradigm. Over three age groups (2, 3 and 5 month olds) the cortical activation increased dramatically. All infant groups showed significant activation when moving displays was contrasted to static displays on a video screen. The study shows that 5-month-old infants and older can be expected to process motion in a similar fashion as adults. Study II covers the infant mirror neuron system (MNS). In adults the mu rhythm perturbations is considered a reliable measure of activation of the MNS. This study presented both a mu rhythm analysis and a ERP analysis to detect MNS activity in 6-month-olds and in adults. This study concludes that the infant MNS can be measured using ERPs and that the development of mu rhythm perturbations requires further study. Study III focused on exploring the mu rhythm suppressions. 8-month-olds observed a live actor that performed goal directed reaches and non-goal directed hand movements. The results show robust mu rhythm perturbations time-locked to the grasping moment. The study concluded that the MNS activity is possible to evaluate by analysis of mu rhythm perturbations and that the MNS show mature characteristics at the age of 8 months. In summary, Study 2 and 3 present new methods to investigate the infant mirror neuron system and shows that the infant MNS is active at 6 months of age. At 8 months of age the infant MNS show mature EEG responses to simple actions such as reaching. How the MNS development relates to the infants’ motor development, and how the MNS interacts with the development of social skills requires further studies that could benefit from the methods presented here.
78

A Study of Output Impedance Effects in Current-Steering Digital-to-Analog Converters

Sadda, AlajaKumari, Madavaneri, Niraja January 2013 (has links)
In this thesis, we have explained the different types of DAC (Digital-to-Analog) architectures and their advantages and disadvantages. We have mainly focused on current-steering digital-to-analog design for achieving high speed and high performance. The current-steering DAC is designed using binary weighted architecture. The benefits of this architecture is that it occupies less area, consumes less power and the number of control signals required are very less. The requirements for high speed and high performance DAC are discussed in detail. The circuit is implemented in a state-of-the-art 65 nm process, with a supply voltage of 1.2 V and at a sampling speed of 2 GHz. The resolution of the DAC is 8-bits. The design of 8-bit current-steering DAC converts 8 most significant bits (MSBs) into their binary weighted equivalent, which controls 256 unit current sources. The performance of the DAC is measured using the static and dynamic  parameters. In communication applications the static performance measures such as INL and DNL are not of utmost importance. In this work, we have mainly concentrated on the dynamic performance characteristics like SNR (Signal to Noise Ratio) and SFDR (Spurious Free Dynamic Range). For measuring the dynamic parameters, frequency domain analysis is a better choice. Also, we have discussed how the pole-zero analysis can be used to arrive at the dynamic performance metrics of a unit element of the DAC at higher frequencies. Different methods were discussed here to show the effects of poles and zeroes on the output impedance of a unit element at higher frequencies, for example, by hand calculation, using Mathematica and by using cadence. After extensive literature studies, we have implemented a technique in cadence, to increase the output impedance at higher frequencies. This technique is called as “complimentary current solution technique”. This technique will improve the output impedance and SFDR compared to the normal unit element design. Our technique contains mostly analog building blocks, like, current mirrors, biasing scheme and switching scheme and few digital blocks like D-ff (D-flip flop). The whole system is simulated and verified in MATLAB. Dynamic performances of the DAC such as SNR and SFDR are found with the help of MATLAB.
79

The Closed Circle of Empathy: Mirror Neuron System Activation and Anterior EEG Asymmetries in Response to Outgroup Members

Gutsell, Jennifer Nadine 14 July 2009 (has links)
Empathy varies with similarity and familiarity of the other. Since outgroups are seen as dissimilar to the self, empathy might be restricted to the ingroup. We looked at two neural correlates of empathy: mirror neuron system activation as indicated by electroencephalographic mu suppression and prefrontal alpha asymmetry. Non black participants watched videos of ingroup and outgroup members acting and expressing emotions, and then acted and experienced emotions themselves. Due to methodological problems, mirror neuron system activation was not obtained. However, anterior asymmetries indicated avoidance motivation during the experience of sadness and the mere observation of sad ingroup members while participants did not show anterior asymmetry when observing the black outgroup. These findings suggest that empathy is bounded to a closed circle of similar others.
80

The Closed Circle of Empathy: Mirror Neuron System Activation and Anterior EEG Asymmetries in Response to Outgroup Members

Gutsell, Jennifer Nadine 14 July 2009 (has links)
Empathy varies with similarity and familiarity of the other. Since outgroups are seen as dissimilar to the self, empathy might be restricted to the ingroup. We looked at two neural correlates of empathy: mirror neuron system activation as indicated by electroencephalographic mu suppression and prefrontal alpha asymmetry. Non black participants watched videos of ingroup and outgroup members acting and expressing emotions, and then acted and experienced emotions themselves. Due to methodological problems, mirror neuron system activation was not obtained. However, anterior asymmetries indicated avoidance motivation during the experience of sadness and the mere observation of sad ingroup members while participants did not show anterior asymmetry when observing the black outgroup. These findings suggest that empathy is bounded to a closed circle of similar others.

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