Episodic memory is a critical component of human cognition. Episodic memory involves recollection of the contextual details surrounding an event, the capacity for mental time travel of past and future events, and is characterized by the subjective awareness that an event has been personally experienced. It is fundamental to our understanding of this complex memory system to examine how episodic memory emerges during the course of development. The present investigation explored the developmental improvement in episodic memory processing assessing recollection of factual information and the source of this information (i.e., source memory) between early to middle childhood. The electrophysiological (EEG) correlates of fact and source memory processing and measures of executive function were also examined as potential sources of variation in episodic memory. The focus of Study 1 was to examine source memory development in early childhood in a sample of 4- and 6-year-olds. Results revealed that older children were better able to recall both fact and source information. Source memory measures were correlated to early executive ability, namely measures of working memory, inhibitory control and set-shifting. Frontal EEG accounted for unique variation in fact recall but not source recall, whereas temporal EEG did not predict fact or source recall performance. The focus of Study 2 was to examine source memory development in middle childhood in a sample of 6- and 8-year-olds. Older children were better on fact recall, but both ages were comparable on source recall. Frontal EEG uniquely predicted fact recall performance beyond the contribution of age and language. Both frontal and parietal EEG and executive function predicted variation in source recall performance. In contrast, temporal EEG did not uniquely predict fact or source recall performance. Lastly, Study 3 was a longitudinal investigation of source memory between early and middle childhood. Although age-related increases in performance were evident, Time 1 and Time 2 source memory measures were not correlated. This investigation contributes to our understanding of the developmental changes in source memory processing between early and middle childhood, and identifies that patterns of frontal and parietal brain activity and executive function skills contribute to early episodic memory formation. / Ph. D.

In all past research, iconic memory shows a significant benefit over visual working memory for storage capacity of visual items. However, this effect has only been studied on simple items such as colors and letters. The goal of this thesis was to determine whether an iconic benefit also exists for visual stimuli with higher visual complexity, such as shapes and faces. Five experiments tested iconic and working memory capacity for complex face stimuli, intermediate-complexity shape stimuli, and simple color stimuli, as well as examining feature binding of objects in iconic memory. Results from these five experiments indicated that increased visual complexity of stimuli negatively impacts the iconic capacity benefit. High- and intermediate-complexity items had little to no iconic benefit, unlike all previously tested simple stimuli. Iconic memory may only be able to represent simple features, or may not be able to transfer complex information into visual working memory as quickly as simple information. Additionally, results showed that feature representations in iconic memory were sometimes bound into complex objects. The results of these five experiments challenge the traditional characterization of visual sensory memory as a precise snapshot; this early memory store may be more complex than a simple visual icon.

Since the dawn of computing, all practical computing systems, from small laptops and cellphones to large mainframes and supercomputers, have been based on the Von Neumann architecture. In this architectural model, computing units and storage units are physically separated, requiring the computing system to spend most of its time and energy on moving data around. As many recently developed applications are driven by large volumes of digital data, the Von Neumann architecture does not scale well with today’s computational demands. In-memory computing using emerging non-volatile device technologies is a promising orthogonal approach as it mitigates the adverse effects of the physical separation, also known as the Von Neumann bottleneck, by merging storage and memory units. The first part of this thesis is focused on synthesis, verification, and fault-tolerance techniques for flow-based in-memory computing. In synthesis, computations are mapped onto nanoscale crossbars of non-volatile memory devices with the objective of minimizing energy, latency, and/or area for flow-based computations. The objective of verification is to show equivalence or non-equivalence between the computational model and a specification, as logical errors can be introduced during the complex stages of synthesis. Finally, fault-tolerance techniques are explored to ensure correctness of the computations at runtime while handling device errors and to elongate the computing system's lifetime. Lastly, path-based computing is introduced, a novel in-memory computing paradigm. In contrast with flow-based computing, which is a WRITE-based computing paradigm, path-based computing is READ-based. This entails that reprogramming of the non-volatile memory devices is not required during computation. As WRITE operations have higher energy cost than READ operations, path-based computing is more energy-efficient than WRITE-based digital computing paradigms. In summary, this thesis presents a wide variety of synthesis, verification, and fault-tolerance techniques (design automation tools) for in-memory computing, paving way for a new era of energy-efficient data-intensive computing.

Digitized by Kansas Correctional Industries

Digitized by Kansas Correctional Industries

Typescript. / Digitized by Kansas Correctional Industries

Thesis (M.A.)--University of South Africa, 1992.

No description available.

No description available.

This thesis is an examination of the extent to which the work of Christa Wolf post-unification can be interpreted as Wolf's response to the attacks on her in the 'deutsch-deutscher Literaturstreit' of 1990 and to the negative publicity generated by her Stasi revelations in January 1993. This thesis will also consider Wolf's post-unification work in the context of her characteristic aesthetic of 'subjektive Authentizität'. Chapter One examines the nature of the accusations levelled against Wolf in both the 'Literaturstreit' and the media furore following her Stasi revelations, notably the allegations of complicity with the SED regime and prolonged allegiance to socialist ideals. The chapter also discusses criticism, expressed in these controversies, of Wolf’s writing as 'littérature engagée'. Chapter Two analyses the collection 'Auf dem Weg nach Tabou' (1994) which, with its emphasis on Wolf's own sense of changing status as a writer in post-unification Germany and her concern with 'Vergangenheitsbewältigung', can be read as Wolf's explicit response to issues raised in the controversies. Chapter Three considers the collection 'Hierzulande Andernorts' (1999), where Wolf's concern with 'Vergangenheitsbewältigung', in the sense of both personal and collective experience of the GDR, continues but where her responses to issues in the controversies are conveyed more subtly, whilst additionally providing insight into Wolf's reflections on 'littérature engagée' and its relevance to her own distinct narrative concept of 'subjektive Authentizität'. Chapter Four analyses the novel 'Medea. Stimmen' (1996) which, with its focus on the 'rehabilitation' of a mythical figure and the theme of victimisation, continues Wolf's preoccupation with the broader theme of going back to the past in order to confront unresolved issues in the present. Chapter Five examines the narrative 'Leibhaftig' (2002) which, with the reworking of Wolf's memories of the GDR as well as the Third Reich and the treatment of the theme of guilt for the failure of the utopian socialist project in the GDR, constitutes not only Wolf's continued concern with 'Vergangenheitsbewältigung' at a personal level but also a reassertion of Wolf's concept of 'subjektive Authentizität'. The conclusion will propose a detailed study of Wolf's final novel 'Stadt der Engel oder The Overcoat of Dr. Freud' (2010) as the natural progression for future research, and in the context of a contribution to the nascent field of memory studies.