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  • Factitious Virtue

    Author:
    Mark Alfano
    Year of Dissertation:
    2011
    Program:
    Philosophy
    Advisor:
    Jesse Prinz
    Abstract:

    The primary aim of this project is to argue that empirical challenges to moral theories like virtue ethics should be co-opted rather than resisted. Virtue ethics has much to offer. Its vision of a flourishing life seems a better object of moral contemplation and evaluation than the sometimes dry rules of deontology and consequentialism; its focus on "thick" concepts like honesty and courage seems to bridge the is/ought gap; its weaving together of reasons and motivations obviates concerns about moral schizophrenia. Furthermore, the virtue ethical account of action paints a detailed picture of sensitivity to reasons, careful and correct construal of ambiguous information, and thoughtful deliberation. Recently, however, philosophers informed by the situationist tradition in social psychology have begun to question the empirical presuppositions of virtue ethics, and a cottage industry has grown up around attacking and defending their arguments. To move the debate forward, I develop a comprehensive list of the empirical presuppositions of virtue ethics, the most contentious items of which are consistency (if an agent possesses a virtue sensitive to reason r, then she responds to r whenever it is relevant), explanatory power (if an agent possesses a virtue, then reference to that virtue sometimes explains her behavior), predictive power (if an agent possesses a virtue, then reference to that virtue sometimes enables prediction of her behavior), and egalitarianism (almost anyone can be virtuous). The empirical challenge relates to the conjunction of these four claims. Nearly a century of studies in social psychology has shown that most people respond primarily not to the reasons there are for them to act on a given occasion but to situational factors like ambient sounds, ambient smells, moods and emotions, and presence of bystanders. These morally irrelevant but causally powerful factors can be unified under the heading of attentional focus: loud and annoying sounds, unpleasant smells, negative moods and emotions, and the presence of bystanders all lead to the focusing of attention on a small number of situational features, while their opposites lead to the dilation of attention. When their attention is focused, people exhibit inattentional blindness, which leads them to miss or misconstrue important moral features of their situations. Insensible to the reasons there are for them to act, they deliberate poorly (if at all) and act in violation of virtue. Situationist psychology does not just deny character traits. It also explains away the strongly felt intuition that there are character traits, invoking a virtual pantheon of gods of error and ignorance that includes the power of (mis)construal (misinterpreting ambiguous information as evidence for character traits), selection bias (using non-representative samples of behavior, thus overlook cases where people act in violation of traits), availability bias (assuming that first impressions are representative), and confirmation bias (seeking and using only evidence that confirms first impressions). These mechanisms guarantee that intuition would lead us to believe in traits even if traits did not exist. Since one does not know that p if one would believe p were it false, we cannot know on the basis of intuitions that character traits exist. Three primary responses to the situationist critique can be identified in the literature. The dodge: virtue is a rare ideal, so data showing that most people are not virtuous is moot. The counterattack: the data do not support the situationist critique. The retreat: although the situationist critique shows that global traits do not exist, a naturalistic theory of virtue can still be formulated in terms of actions or local traits. Unfortunately, most versions of these arguments are either unsound or give up the consistency, explanatory power, predictive power, or egalitarianism of virtue. The dodge, for instance, is an outright denial of egalitarianism. Most versions of the counterattack fail to individuate virtues by their characteristic reasons, and thus are morally inadequate; others appeal to unreliable intuitions. Two compatible tactics for dealing with the challenge, however, do emerge from this literature: an emphasis on what I call the portability of context and a shift from situation-consumerism to situation-producerism. By recognizing the power of situations and identifying the types of situations (not) conducive to behavior in accordance with virtue, one can strategically seek (avoid) situations likely to lead to (non-)virtuous actions. And by recognizing the causal dialectic between agents and situations, one can shift to thinking of agents as active producers rather than passive consumers of situations - a point of view that encourages the creation of situations conducive to action in accordance with virtue. Along these lines, I argue that virtue (though not vice) attributions of the right sort should be made regardless of their truth-value. Drawing on formal work in multi-agent epistemic logic and empirical studies in social psychology, consumer research, and behavioral economics, I show that the plausible, public attribution of virtuous traits induces both identification with those traits and belief that others expect one to act in trait-consonant ways, which in turn leads to trait-consonant behavior. The notions of placebo effects and self-fulfilling prophecies are instructive parallels to virtue-labeling. Thinking of virtue attributions merely as true or false is too limited. We must recognize in addition a third category: factitious attributions, which become true by being plausibly, publicly announced. In another example of the portability of context and situation-producerism, I present a novel theory of social distance in terms of potential for interaction, group identity, and information. This theory draws support from recent work by experimental psychologists and economists, as well as an experiment that I myself conducted. By manipulating heuristics that track social distance, agents can be led systematically to underestimate it, which in turn leads to elevated levels of behavior in accordance with virtue.

  • Does Discovery-Based Instruction Enhance Learning?

    Author:
    Louis Alfieri
    Year of Dissertation:
    2010
    Program:
    Psychology
    Advisor:
    Patricia Brooks
    Abstract:

    Since Bruner's (1961) call for research into discovery-based learning, controversy has surrounded the efficacy of such a constructivist approach to instruction (e.g., Tobias & Duffy, 2009). For decades, research has investigated to what extent discovery-based instruction enhances learning tasks or conversely, detracts from them. Research has included wide varieties of domains and discovery-based instructional approaches. Samples have included both children and adults and both novices and experts within their specific domains. It seems that what the field needs is a definition of discovery learning from a practical perspective because a review of the literature reveals that although there might be an implied sense of what discovery learning is, the methodologies employed vary greatly. Furthermore, the characteristics of effective discovery methodology(s) need to be examined with careful consideration of the domain involved, the age of the sample, the comparison condition, and the outcome assessments. Therefore, two meta-analyses were conducted using a sample of 164 studies: the first examined the effects of unassisted discovery learning versus explicit instruction and the second examined the effects of enhanced and/or assisted discovery versus other types of instruction (e.g., explicit, unassisted discovery, etc.). Random effects analyses of 580 comparisons revealed that outcomes were favorable for explicit instruction when compared to unassisted discovery under most conditions, d = -.38 (95% CI = -.44/-.31). In contrast, analyses of 360 comparisons revealed that outcomes were favorable for enhanced discovery when compared to other forms of instruction, d = .30 (95% CI = .23/.36). The findings suggest that unassisted discovery does not benefit learners, whereas feedback, worked examples, scaffolding, and elicited explanations do.

  • The Temporal Relationship between Daytime Napping and Memory Consolidation

    Author:
    Sara Alger
    Year of Dissertation:
    2011
    Program:
    Psychology
    Advisor:
    William Fishbein
    Abstract:

    An extensive body of literature exists substantiating the idea that sleep facilitates the strengthening, stabilization, and protection of newly formed memories, aiding in consolidation from short-term to long-term stores. However, research as to the temporal boundaries of the benefit of sleep to declarative memory is deficient. It has been established that sleep benefits memory compared to equal time spent awake, but when sleep needs to occur relative to the learning period, as well as how much and what type of sleep is necessary, has been little explored. Additionally, researchers have focused on how the brain works on previously encoded information during sleep, but very few have addressed whether sleep prepares the brain to take on new information when it occurs prior to learning. Using efficient daytime naps, the present series of studies addressed these shortcomings and the results provided support exclusively to an active role for sleep in memory processing. Study I unexpectedly demonstrated superior performance for recognition memory with increased delay before sleep onset, resulting in increased slow wave sleep (SWS) in the later nap groups. Study II determined that sleep must progress into SWS, rather than merely Stages 1 and 2, for better short-term retention, subsequent protection from stimulus-related interference, and long-term consolidation, although even a brief nap provides temporary retention benefits over remaining awake. Examining sleep prior to learning in Study III, it was found that a 60-minute nap prepared the brain to more efficiently consolidate information, despite the fact that nap and wake groups encoded material equally. Overall, the present research provides clarification, although perhaps task-dependent, to the existing questions regarding the temporal relationship between sleep and learning. Additionally, the results proffer support for active processing during sleep potentially through standard consolidation and/or homeostatic downscaling of synaptic potentials, the major mechanistic theories ascribing a role for SWS in declarative memory processing.

  • IN THESE BONES THE ECONOMY OF THE WORLD: A MULTI-LOGICAL, MULTI-REPRESENTATIONAL CULTURAL STUDY

    Author:
    Carolyne Ali-Khan
    Year of Dissertation:
    2011
    Program:
    Urban Education
    Advisor:
    Kenneth Tobin
    Abstract:

    In this work I offer critical interpretations of street skaters, images in schools, collaborative writing and discourses on Muslims in schools. Employing a phenomenological, hermeneutic approach, I have thought back on my experiences, made claims and supported them hermeneutically. As I have (in the tradition of critical pedagogy) told stories of being in the world, a critical perspective has anchored these stories to broader social, political and economic frameworks. Axiological concerns are at the forefront of this work, and the "so what?" question implicitly weaves through it. I do not seek to provide the answers, but rather to illuminate, through example, that asking questions of that which is taken for granted and connecting these questions to issues of power is a valid undertaking. In a world of truncated educational "accountability" this work joins those that seek to offer a counterpoints. This dissertation explores work that has been done over the past three years in a variety of pedagogical contexts. As a manuscript style dissertation, it sews together freestanding texts with the thread of critical pedagogy. Each chapter (including half of the first chapter) has been published, only the last chapter (which discusses future work) is new. In each of these research projects I set out to use interdisciplinary and multi-textual approaches to focus on "other" ways of being in the world, and to question privileging practices and discourses that have been normalized in everyday life. As a bricolage, this work brings together multiple disciplines and theoretical discourses. I draw from a range of critical pedagogies and visual and literary methods. Throughout, I employ autoethnography as an entry point, to render accessible the worlds and worldviews that I seek to shed light on.

  • Power Supply Considerations for Capacitive Deionization Water Purification Systems

    Author:
    Mohammad Alkuran
    Year of Dissertation:
    2009
    Program:
    Engineering
    Advisor:
    Professor Norman Scheinberg
    Abstract:

    This research is about the power supply considerations and energy recovery schemes in water purification systems utilizing the Capacitive De-Ionization (CDI) method. The first chapter is a general introduction about the ever rising need for water in the world. It also talks about the drive behind this research. The most common methods for water desalination are discussed in Chapter II. Then, the method of CDI is discussed in detail in Chapter III. The model, applications and design considerations for CDI are discussed. Energy recovery in desalination methods is talked about in Chapter IV, with emphasis on energy recovery in CDI. Then a novel method for energy recovery in CDI is presented, showing superior results to prior art. Simulation and experimental results confirmed the validity of the method, and are presented. Power supply considerations for the CDI method are presented in Chapter V. Then, a novel power supply scheme is suggested.

  • THE EFFECTS OF ENRICHMENT ON COGNITION IN RATS (RATTUS NORVEGICUS)

    Author:
    Amber Alliger
    Year of Dissertation:
    2009
    Program:
    Psychology
    Advisor:
    Peter Moller
    Abstract:

    Abstract THE EFFECTS OF ENRICHMENT ON COGNITION IN RATS RATTUS NORVEGICUS by Amber A. Alliger Adviser: Dr. Peter Moller Animal models play an integral role in pharmaceutical research when developing drugs for human use. It is therefore imperative that animal models accurately represent human systems. In an attempt to reduce variability of test results, animals are often kept in barren, non-natural conditions. There is, however, a growing awareness that environmental enrichment will increase the validity of test results. The aim of the present study was to allow animals to control their environment using operant conditioning procedures, and to assess the effect of control on cognitive tasks. Four predictions were tested: 1. Rats (Rattus norvegicus) will control three stimuli (light, sound and a running wheel). 2. Animals will exhibit preferences for particular stimulus strengths. 3. Animals that exert control over the environmental stimuli will show increased performance in cognitive tasks compared to animals that lack control.4. Animals that can control environmental stimuli will have lower corticosterone levels than animals that lack such control, where corticosterone levels are used as an assessment of stress. Experimental subjects in both experiments did show control over a light stimulus, and performed significantly better in a discrimination task as compared with subjects that could not control their environment. There was no difference in corticosterone levels between control and experimental subjects. These results will contribute to an understanding how enrichment and control of environmental stimuli, in particular, affect the welfare of animals in captive environments, and aid in designing experimental conditions that will produce animal models that will increase validity and reliability in research.

  • The Vocal Behaviors of Captive North American River Otters (Lontra canadensis) Individual differences and shared repertoires

    Author:
    Carla Almonte
    Year of Dissertation:
    2011
    Program:
    Biology
    Advisor:
    Richard Veit
    Abstract:

    The current information on the vocal repertoire of the North American River Otter is very limited. To date there have been no direct studies conducted on their repertories. In this study, I examined the vocal behavior of 12 captive river otters. The discriminant function analysis suggests that river otters have 4 distinct call types with 7 sub-call types and one call the whistle is unique to one group of pups. The results of the Kruskal-Wallis comparing acoustical structures shows strong evidence for the presence of individuality with some individuals showing greater differences in comparison to the others. I also examined the differences in sexes and age groups, and the results show that unique calls are present, and there are significant differences across groups when comparing acoustical structures. Finally, I examined the uses of vocalizations, and the results show a positive correlation between the duration, max frequency, and max power of the call and the arousal state of the individual producing the call. Specific call types also showed tendencies to be produced when the individual was in a particular interaction (asocial or social) and when in a particular arousal state.

  • ROUTING PROTOCOLS ENHANCEMENT FOR DELAY TOLERANT NETWORKS

    Author:
    Fuad Alnajjar
    Year of Dissertation:
    2010
    Program:
    Engineering
    Advisor:
    Tarek Saadawi
    Abstract:

    Routing in Delay/Disruption Tolerant Networks (DTN) is active area of research and acquires the attention of researchers as being the most adequate solution for the problem of intermittently connection in Mobile Ad hoc Networks (MANET). The challenge is to find a routing algorithm that can deal with dynamic environment causing networks to split and merge, considering nodes mobility. In this dissertation we enhance the performance of DTN routing protocols in Delay Tolerant Mobile Ad Hoc Networks by accomplishing the following goals to address the routing challenges: * Design a new probabilistic routing protocol based on history of encountered nodes. * Determination of strength and weakness of DTN routing protocols by comparison. * Enhancing DTN routing protocols by inclusion of study of the impact of link availability on performance of the DTN-based protocols * A Cross Layer Design (CLD) to enhance service quality of some common MANET-based routing protocols. v We have designed a DTN-based probabilistic routing algorithm using the concept of History of Encounters, HEPRA. Our routing protocol relies on the knowledge of the mobility of nodes and uses the history of encountered nodes to predict its future suitability to deliver messages to next node toward destination. The probabilistic routing approach is built on a store-carry-forward network to deliver messages to final destination in MANET environment. We evaluate the performance of HEPRA in various network environment behaviors. We present an evaluation and analysis of performances of some common DTN routing protocols including HEPRA in terms of different parameters in MANET environment. We illustrate the behaviors of the DTN routing protocols in terms of various parameters and variables. This evaluation presents the strengths and weakness of selected protocols. We study the impact of link availability as a parameter of the physical layer environment on the performance of DTN routing protocols. This study is the first research analysis of the impact of physical layer parameters on the performance of DTN routing protocols. We demonstrate through the simulation how those protocols act against changes in network environment. We propose a CLD to attain a reliable data transmission in MANET. We present a model that allows the network layer to adjust its routing protocol dynamically based on Signal Noise Ratio (SNR) and Received Power (RP) along the end-to-end routing path for each transmission link to improve the end-to-end routing performance in MANET environment. In this dissertation, we present the design basis for those contributions, illustrate and evaluate our design efforts, and discuss the advantages of our models.

  • Molecular Dynamics of Shock Wave Interaction with Nanoscale Structured Materials

    Author:
    Ahmad AL-QANANWAH
    Year of Dissertation:
    2012
    Program:
    Engineering
    Advisor:
    Yiannis Andreopoulos
    Abstract:

    Typical theoretical treatments of shock wave interactions are based on a continuum approach, which cannot resolve the spatial variations in solids with nano-scale porous structure. Nano-structured materials have the potential to attenuate the strength of traveling shock waves because of their high surface-to-volume ratio. To investigate such interactions we have developed a molecular dynamics simulation model, based on Short Range Attractive interactions. A piston, modeled as a uni-directional repulsive force field translating at a prescribed velocity, impinges on a region of gas which is compressed to form a shock, which in turn is driven against an atomistic solid wall. Periodic boundary conditions are used in the directions orthogonal to the piston motion, and we have considered solids based on either embedded atom potentials (target structure) or tethered potential (rigid piston, holding wall). Velocity, temperature and stress fields are computed locally in both gas and solid regions, and displacements within the solid are interpreted in terms of its elastic constants. In this work we present results of the elastic behavior of solid structures subjected to shock wave impact and analysis of energy transport and absorption in porous materials. The results indicated that the presence of nano-porous material layers in front of a target wall reduced the stress magnitude detected inside and the energy deposited there by about 30 percent while, at the same time, its loading rate was decreased substantially

  • Making Conversation: The Poetics of Voice in Modernist Fiction

    Author:
    Elizabeth Alsop
    Year of Dissertation:
    2012
    Program:
    Comparative Literature
    Advisor:
    John Brenkman
    Abstract:

    This dissertation examines the function of dialogue within modernist fiction, and argues that it can be seen to assume a substantially expanded and diversified role in early twentieth-century narrative texts. While existing accounts of fictional speech stress its capacity to develop character or advance plot, I contend that modernist authors began using speech differently than it had historically been used in the novel: less for characterizing and plot-advancing purposes, than for rhetorical and poetic ones. My primary case studies include a cross-section of British and American modernist texts - including Henry James's The Ambassadors, Ernest Hemingway's The Sun Also Rises, James Joyce's "The Dead," Virginia Woolf's The Waves, and William Faulkner's The Sound and the Fury and Absalom, Absalom! - as well as examples from post-War Italian narrative, which reflect the influence of Anglophone modernism. Through close, comparative analyses of how fictional voice is deployed in these texts, and by drawing on a range of literary and narrative theory (by Mikhail Bakhtin, Franco Moretti, and Sharon Cameron among others) I demonstrate that these writers frequently "make" conversation less to express character, than to communicate ideas or affects that exceed character. In particular, I disclose the tendency for discourse within these fictional environments to belong to more than one speaker - or conversely, to none. By challenging the attributive logic used to make sense of represented speech, these texts encourage us to refocus our critical attention away from discrete utterances, and toward the larger system of utterances that emerges in a given work. In this way, I argue, modernist fiction seems to demand (and reward) a new mode of reading and interpreting fictional dialogue: one which takes into account how characters say, as well as what they say, and which treats dialogue's form as at least as rich a source of meaning as its content.