Deterministic Computations Whose History Is Independent of the Order of Asynchronous Updating

Consider a network of processors (sites) in which each site x has a finite set N(x) of neighbors. There is a transition function f that for each site x computes the next state ξ(x) from the states in N(x). But these transitions (updates) are applied in arbitrary order, one or many at a time. If the state of site x at time t is η(x; t) then let us define the sequence ζ(x; 0); ζ(x; 1), ... by taking the sequence η(x; 0),η(x; 1), ... , and deleting each repetition, i.e. each element equal to the preceding one. The function f is said to have invariant histories if the sequence ζ(x; i), (while it lasts, in case it is finite) depends only on the initial configuration, not on the order of updates. This paper shows that though the invariant history property is typically undecidable, there is a useful simple sufficient condition, called commutativity: For any configuration, for any pair x; y of neighbors, if the updating would change both ξ(x) and ξ(y) then the result of updating first x and then y is the same as the result of doing this in the reverse order. This fact is derivable from known results on the confluence of term-rewriting systems but the self-contained proof given here may be justifiable.

A Short History of Computational Complexity

National Science Foundation (CCR-998310); Army Research Office (DAAD19-02-1-0058)

Speaker Normalization Using Cortical Strip Maps: A Neural Model for Steady State Vowel Identification

Auditory signals of speech are speaker-dependent, but representations of language meaning are speaker-independent. Such a transformation enables speech to be understood from different speakers. A neural model is presented that performs speaker normalization to generate a pitchindependent representation of speech sounds, while also preserving information about speaker identity. This speaker-invariant representation is categorized into unitized speech items, which input to sequential working memories whose distributed patterns can be categorized, or chunked, into syllable and word representations. The proposed model fits into an emerging model of auditory streaming and speech categorization. The auditory streaming and speaker normalization parts of the model both use multiple strip representations and asymmetric competitive circuits, thereby suggesting that these two circuits arose from similar neural designs. The normalized speech items are rapidly categorized and stably remembered by Adaptive Resonance Theory circuits. Simulations use synthesized steady-state vowels from the Peterson and Barney [J. Acoust. Soc. Am. 24, 175-184 (1952)] vowel database and achieve accuracy rates similar to those achieved by human listeners. These results are compared to behavioral data and other speaker normalization models.

Vector Associative Maps: Unsupervised Real-time Error-based Learning and Control of Movement Trajectories

This article describes neural network models for adaptive control of arm movement trajectories during visually guided reaching and, more generally, a framework for unsupervised real-time error-based learning. The models clarify how a child, or untrained robot, can learn to reach for objects that it sees. Piaget has provided basic insights with his concept of a circular reaction: As an infant makes internally generated movements of its hand, the eyes automatically follow this motion. A transformation is learned between the visual representation of hand position and the motor representation of hand position. Learning of this transformation eventually enables the child to accurately reach for visually detected targets. Grossberg and Kuperstein have shown how the eye movement system can use visual error signals to correct movement parameters via cerebellar learning. Here it is shown how endogenously generated arm movements lead to adaptive tuning of arm control parameters. These movements also activate the target position representations that are used to learn the visuo-motor transformation that controls visually guided reaching. The AVITE model presented here is an adaptive neural circuit based on the Vector Integration to Endpoint (VITE) model for arm and speech trajectory generation of Bullock and Grossberg. In the VITE model, a Target Position Command (TPC) represents the location of the desired target. The Present Position Command (PPC) encodes the present hand-arm configuration. The Difference Vector (DV) population continuously.computes the difference between the PPC and the TPC. A speed-controlling GO signal multiplies DV output. The PPC integrates the (DV)·(GO) product and generates an outflow command to the arm. Integration at the PPC continues at a rate dependent on GO signal size until the DV reaches zero, at which time the PPC equals the TPC. The AVITE model explains how self-consistent TPC and PPC coordinates are autonomously generated and learned. Learning of AVITE parameters is regulated by activation of a self-regulating Endogenous Random Generator (ERG) of training vectors. Each vector is integrated at the PPC, giving rise to a movement command. The generation of each vector induces a complementary postural phase during which ERG output stops and learning occurs. Then a new vector is generated and the cycle is repeated. This cyclic, biphasic behavior is controlled by a specialized gated dipole circuit. ERG output autonomously stops in such a way that, across trials, a broad sample of workspace target positions is generated. When the ERG shuts off, a modulator gate opens, copying the PPC into the TPC. Learning of a transformation from TPC to PPC occurs using the DV as an error signal that is zeroed due to learning. This learning scheme is called a Vector Associative Map, or VAM. The VAM model is a general-purpose device for autonomous real-time error-based learning and performance of associative maps. The DV stage serves the dual function of reading out new TPCs during performance and reading in new adaptive weights during learning, without a disruption of real-time operation. YAMs thus provide an on-line unsupervised alternative to the off-line properties of supervised error-correction learning algorithms. YAMs and VAM cascades for learning motor-to-motor and spatial-to-motor maps are described. YAM models and Adaptive Resonance Theory (ART) models exhibit complementary matching, learning, and performance properties that together provide a foundation for designing a total sensory-cognitive and cognitive-motor autonomous system.

Fuzzy ARTMAP: A Neural Network Architecture for Incremental Supervised Learning of Analog Multidimensional Maps

A new neural network architecture is introduced for incremental supervised learning of recognition categories and multidimensional maps in response to arbitrary sequences of analog or binary input vectors. The architecture, called Fuzzy ARTMAP, achieves a synthesis of fuzzy logic and Adaptive Resonance Theory (ART) neural networks by exploiting a close formal similarity between the computations of fuzzy subsethood and ART category choice, resonance, and learning. Fuzzy ARTMAP also realizes a new Minimax Learning Rule that conjointly minimizes predictive error and maximizes code compression, or generalization. This is achieved by a match tracking process that increases the ART vigilance parameter by the minimum amount needed to correct a predictive error. As a result, the system automatically learns a minimal number of recognition categories, or "hidden units", to met accuracy criteria. Category proliferation is prevented by normalizing input vectors at a preprocessing stage. A normalization procedure called complement coding leads to a symmetric theory in which the MIN operator (Λ) and the MAX operator (v) of fuzzy logic play complementary roles. Complement coding uses on-cells and off-cells to represent the input pattern, and preserves individual feature amplitudes while normalizing the total on-cell/off-cell vector. Learning is stable because all adaptive weights can only decrease in time. Decreasing weights correspond to increasing sizes of category "boxes". Smaller vigilance values lead to larger category boxes. Improved prediction is achieved by training the system several times using different orderings of the input set. This voting strategy can also be used to assign probability estimates to competing predictions given small, noisy, or incomplete training sets. Four classes of simulations illustrate Fuzzy ARTMAP performance as compared to benchmark back propagation and genetic algorithm systems. These simulations include (i) finding points inside vs. outside a circle; (ii) learning to tell two spirals apart; (iii) incremental approximation of a piecewise continuous function; and (iv) a letter recognition database. The Fuzzy ARTMAP system is also compared to Salzberg's NGE system and to Simpson's FMMC system.

The Queen's College, Cork: its origins and early history, 1803-1858

This work examines the origins and early history of the Queen's College, Cork. Designedly there is as much stress on the origins as on the early history, for it is the contention of the work that the College was something more than a legislative mushroom. It was very much in the tradition of the civic universities which added an exciting new dimension to academic life in these islands in the nineteenth century. The first chapter surveys university practice and thinking at the opening of the century, relying exclusively on published sources. The second chapter is devoted specifically to the state of learning in Cork during the period, and makes extensive use of hitherto unpublished manuscript material in relation to the Royal Cork Institution. The third chapter deals with the highly significant evidence on education embodied in the Report of the Select Committee on Irish Education of 1838. This material has not previously been published. In chapter four an extended study is made of relevant letters in the manuscript correspondence of Sir Robert Peel - even the most recent authoritative biography has ignored this material. The remaining three chapters are devoted more specifically to the College, both in the formulation or policy and in its practical working. In chapter six there is an extended survey of early College life based exclusively on hitherto unpublished manuscript material in the College Archives. All of these sources, together with incidental published material, are set out at the end of each chapter.

The life history and ecology of black scabbardfish (Aphanopus carbo Lowe 1839) in the north-east Atlantic

The black scabbardfish is a deep water species that supports commercial fisheries across a large area of the NE Atlantic shelf. The life history of black scabbardfish is poorly understood and a major unresolved issue is population structure. In this study it was used a combination of methodologies to get further knowledge in the life history and population structure of A. carbo over its wide distribution range in the Northeast Atlantic. The new knowledge acquired during this study, will increase our ability to better manage this species in the NE Atlantic. It has been postulated that fish caught to the west of the British Isles are pre-adults that migrate further south (to Madeira) for spawning, implying a single panmictic population. In this study, specimens of Aphanopus carbo were sampled between September 2008 and May 2010 from two different areas: NW Scotland (French trawlers and deep water surveys) and Madeira Islands (longliners commercial landings). Geographical differences in reproductive state of scabbardfish were evident, supportive of a north-south migration theory. In the northern area, all specimens found were immature, while in Madeira all maturity stages were observed. In Madeira, spawning occurred during the fourth quarter, with peak maturity in October (males) and in November (females). The age of this species has proven difficult and has led to different and contradictory age and growth estimates. For this study, we used two reading interpretations to determine age and estimate the growth parameters. To the west of the British Isles, specimens reached a lower maximum age and had a higher growth rate than those caught off Madeira. These differences are consistent with the theory of a single population of black scabbardfish in the NE Atlantic, highly segregate, with smaller, immature and younger fish caught to the west of the British Isles and bigger and mature caught in Madeira Islands. The feeding ecology showed strong evidence that the diet of black scabbardfish is associated with the spawning migration of blue whiting, which may support a northerly feeding migration theory for black scabbardfish. The stable isotope analyses in the muscle of black scabbardfish identified that black scabbardfish feeds on species with epipelagic and benthopelagic affinities. Comparison with stable isotope analysis in Madeira samples indicated that black scabbardfish feed at a similar trophic level and has the same trophic niche width in both areas, assuming similar baseline isotope compositions. Otolith stable isotopes (oxygen - δ18O and nitrogen - δ15N) analyses were used as a tool to clarify migratory behaviour. Otolith isotope ratios can provide insight into whether adults caught around Madeira fed in an isotopically depleted northerly ecosystem (NW Scotland) during their pre-adult period and then migrate towards south to spawn. Overall, the results support a south-north migration of pre adult fish from spawning areas around Madeira and a north-south migration from the west of Scotland to the spawning areas. Given its life cycle there is an urgent need that the management process recognizes the existence of a continuous widely distributed stock of black scabbardfish between the west of the British Isles and Madeira. The results highlight large scale dispersal in this species which needs to be treated as a highly migratory species and be managed as a single population.

History, revolution and the British popular novel: historical fiction in the romantic age

“History, Revolution and the British Popular Novel” takes as its focus the significant role which historical fiction played within the French Revolution debate and its aftermath. Examining the complex intersection of the genre with the political and historical dialogue generated by the French Revolution crisis, the thesis contends that contemporary fascination with the historical episode of the Revolution, and the fundamental importance of history to the disputes which raged about questions of tradition and change, and the meaning of the British national past, led to the emergence of increasingly complex forms of fictional historical narrative during the “war of ideas.” Considering the varying ways in which novelists such as Charlotte Smith, William Godwin, Mary Robinson, Helen Craik, Clara Reeve, John Moore, Edward Sayer, Mary Charlton, Ann Thomas, George Walker and Jane West engaged with the historical contexts of the Revolution debate, my discussion juxtaposes the manner in which English Jacobin novelists inserted the radical critique of the Jacobin novel into the wider arena of history with anti-Jacobin deployments of the historical to combat the revolutionary threat and internal moves for socio-political restructuring. I argue that the use of imaginative historical narrative to contribute to the ongoing dialogue surrounding the Revolution, and offer political and historical guidance to readers, represented a significant element within the literature of the Revolution crisis. The thesis also identifies the diverse body of historical fiction which materialised amidst the Revolution controversy as a key context within which to understand the emergence of Scott’s national historical novel in 1814, and the broader field of historical fiction in the era of Waterloo. Tracing the continued engagement with revolutionary and political concerns evident in the early Waverley novels, Frances Burney’s The Wanderer (1814), William Godwin’s Mandeville (1816), and Mary Shelley’s Valperga (1823), my discussion concludes by arguing that Godwin’s and Shelley’s extension of the mode of historical fiction initially envisioned by Godwin in the revolutionary decade, and their shared endeavour to retrieve the possibility enshrined within the republican past, appeared as a significant counter to the model of history and fiction developed by Walter Scott in the post-revolutionary epoch.

A social history of sport in Cork, Tipperary and Waterford, c. 1880-1930

This thesis seeks to explore the development of sport in Munster in the late nineteenth and early twentieth centuries by comparing developments in three counties: Cork, Tipperary and Waterford. In particular this thesis considers the development of rugby and soccer in comparative perspective across these three counties, asking what local factors impacted on their uneven development in the region and considering the extent to which the traditional model of diffusion applies to the reception of these sports in the three counties. By giving consideration to these two particular non-indigenous sports, the thesis will, through answering that question, explore ideas of cultural reception, national identity and class as expressed at local level. These themes will be explored by placing the comparative analysis of these two sports into a wider context of sporting development regionally and nationally in the period, in particular the emerging commercialisation of sport, and also the diverse sporting culture of which these two sports were a part. Utilising a wide range of archival sources from local, national and sporting newspapers, to club records, official publications and ephemera this thesis builds a picture of sport in Munster that is deeply rooted in the community, and that forms an important facet of the social world of Cork, Tipperary and Waterford from 1880-1930.

Exploring the Zionist evolution of Robert Briscoe: History and memory

Robert Briscoe was the Dublin born son of Lithuanian and German-Jewish immigrants. As a young man he joined Sinn Féin and was an important figure in the War of Independence due to a role as one of the IRA’s main gun-procuring agents. He took the anti-Treaty side during an internecine Civil War, mainly due to the influence of Eamon de Valera and retained a filial devotion towards him for the rest of his life. In 1926 he was a founding member of Fianna Fáil, de Valera’s breakaway republican party, which would dominate twentieth-century Irish politics. He was first elected as a Fianna Fáil T.D. (Teachta Dála, Deputy to the Dáil) in 1927, and successfully defended his seat eleven times becoming the first Jewish Lord Mayor of Dublin in 1956, an honour that was repeated in 1961. On this basis alone, it can be argued that Briscoe was a significant presence in an embryonic Irish political culture; however, when his role in the 1930s Jewish immigration endeavor is acknowledged, it is clear that he played a unique part in one of the most contentious political and social discourses of the pre-war years. This was reinforced when Briscoe embraced Zionism in a belated realisation that the survival of his European co-religionists could only be guaranteed if an independent Jewish state existed. This information is to a certain degree public knowledge; however, the full extent of his involvement as an immigration advocate for potential Jewish refugees, and the seniority he achieved in the New Zionist Organisation (Revisionists) has not been fully recognised. This is partly explicable because researchers have based their assessment of Briscoe on an incomplete political archive in the National Library of Ireland (NLI). The vast majority of documentation pertaining to his involvement in the immigration endeavor has not been available to scholars and remains the private property of Robert Briscoe’s son, Ben Briscoe. The lack of immigration files in the NLI was reinforced by the fact that information about Briscoe’s Revisionist engagement was donated to the Jabotinsky Institute in Tel Aviv and can only be accessed physically by visiting Israel. Therefore, even though these twin endeavors have been commented on by a number of academics, their assessments have tended to be based on an incomplete archive, which was supplemented by Briscoe’s autobiographical memoir published in 1958. This study will attempt to fill in the missing gaps in Briscoe’s complex political narrative by incorporating the rarely used private papers of Robert Briscoe, and the difficult to access Briscoe files in Tel Aviv. This undertaking was only possible when Mr.Ben Briscoe graciously granted me full and unrestricted access to his father’s papers, and after a month-long research trip to the Jabotinsky Institute in Tel Aviv. Access to this rarely used documentation facilitated a holistic examination of Briscoe’s complex and multifaceted political reality. It revealed the full extent of Briscoe’s political and social evolution as the Nazi instigated Jewish emigration crisis reached catastrophic proportions. He was by turn Fianna Fáil nationalist, Jewish immigration advocate and senior Revisionist actor on a global stage. The study will examine the contrasting political and social forces that initiated each stage of Briscoe’s Zionist awakening, and in the process will fill a major gap in Irish-Jewish historiography by revealing the full extent of his Revisionist engagement.

A history of the Irish Red Cross Society, 1939-1971

This research is concerned with assessing from a national perspective the role, work and historical impact of the Irish Red Cross Society (IRCS) between 1939 and 1971. During this period the IRCS discharged three primary functions: it provided first aid services both in war-time and peace-time; it pioneered public health and social care services; and acted as the State’s main agency for international humanitarian relief measures. Although primarily a national organisational history of the Society, it is not a history in isolation. A broader perspective demonstrates that the work undertaken by the IRCS has relevance to the medical, social, religious, cultural, political and diplomatic history of twentieth century Ireland. This study assesses the impact of a number of significant public health and social care initiatives which the IRCS implemented and developed since its inception and how most of these were subsequently developed independently by the State. During the early 1940s, the Society’s formation of a national blood transfusion service ultimately laid the foundations for the establishment of a national blood transfusion service. The Society’s steering of a national anti-tuberculosis campaign in the 1940s brought the issue of the eradication of TB to the fore and helped to change public attitudes towards the disease. The concept of caring for the needs of the elderly in Ireland was largely unknown until the IRCS began addressing the issue in the 1950s and, for more than two decades, was effectively the only organisation in the State that campaigned and introduced innovative services for the aged. The IRCS made a significant impact in terms of its commitment to the needs of refugees and the provision of international humanitarian relief from Ireland. The Society’s donation in 1945 of a fully equipped hospital to the population of Saint-Lo in France, its war-time overseas relief efforts and its post-war work for child refugees earned Ireland significant international recognition and prestige and, more importantly, justified Ireland’s war-time policy of neutrality. With Ireland’s admission to the UN, the government became more dependent on the IRCS to consolidate that position.

Design history: exploring corporate communities

A design history is a narrative involving a multitude of social groups, interpretive flexibility, and eventual stabilization of shared understanding. Design history surfaces the practices that help shape and define engagements and can increase not only our theoretical understanding of what design is, but also our capacity to realize this understanding in practice. We use a design history perspective to examine how corporate technology initiatives establish and support open source communities and the crafting of relevant design practices that enable their advancement. We foster an evolving expression of design research that treats artifacts not as stable objects to be singularly evaluated, but as evolving systems contingent on historical trajectories.

Reading Lydgate's Troy Book: patronage, politics, and history in Lancastrian England

This thesis, Reading Lydgate's Troy Book: Patronage, Politics and History in Lancastrian England, discusses the relationship between John Lydgate as a court poet to his patron Henry V. I contend that the Troy Book is explored as a vehicle to propagate the idea that the House of Lancaster is the legitimate successor to King Richard II in order to smooth over the usurpation of 1399. Paul Strohm's England's Empty Throne was a key influence to the approach of this thesis' topic. I examine that although Chaucer had a definitive impact on Lydgate's writing, Lydgate is able to manipulate this influence for his own ambitions. In order to enhance his own fame, Lydgate works to promote Chaucer's canon so that as Chaucer's successor, he will inherit more prestige. The Trojan war is seen in context with the Hundred Years War, and can be applied contextually to political events. Lydgate presents characters that are vulnerable to human failings, and their assorted, complicated relationships. Lydgate modernises the Troy Book to reflect and enhance his Lancastrian society, and the thesis gives a contextual view of Lydgate's writing of the Troy Book. Lydgate writes for a more varied target audience than his thirteenth-century source, Guido delle Colonne, and there is a deliberation on the female characters of the Troy Book which promulgates the theory that Lydgate takes a proactive and empathetic interest in women's roles in society. Furthermore Lydgate has never really been accepted as a humanist, and I look at Lydgate's work from a different angle; he is a self-germinating humanist. Lydgate revives antiquity to educate his fifteenth-century audience, and his ambition is to create a memorial for his patron in the vernacular, and enhance his own fame as a poet separate from Chaucer's shadow.

Cross-cultural dimensions of meaning in the evaluation of events in world history? Perceptions of historical calamities and progress in cross-cultural data from 30 societies

The universality versus culture specificity of quantitative evaluations (negative-positive) of 40 events in world history was addressed using World History Survey data collected from 5,800 university students in 30 countries/societies. Multidimensional scaling using generalized procrustean analysis indicated poor fit of data from the 30 countries to an overall mean configuration, indicating lack of universal agreement as to the associational meaning of events in world history. Hierarchical cluster analysis identified one Western and two non-Western country clusters for which adequate multidimensional fit was obtained after item deletions. A two-dimensional solution for the three country clusters was identified, where the primary dimension was historical calamities versus progress and a weak second dimension was modernity versus resistance to modernity. Factor analysis further reduced the item inventory to identify a single concept with structural equivalence across cultures, Historical Calamities, which included man-made and natural, intentional and unintentional, predominantly violent but also nonviolent calamities. Less robust factors were tentatively named as Historical Progress and Historical Resistance to Oppression. Historical Calamities and Historical Progress were at the individual level both significant and independent predictors of willingness to fight for one’s country in a hierarchical linear model that also identified significant country-level variation in these relationships. Consensus around calamity but disagreement as to what constitutes historical progress is discussed in relation to the political culture of nations and lay perceptions of history as catastrophe.

Structure maps for hcp metals from first-principles calculations

The ability to predict the existence and crystal type of ordered structures of materials from their components is a major challenge of current materials research. Empirical methods use experimental data to construct structure maps and make predictions based on clustering of simple physical parameters. Their usefulness depends on the availability of reliable data over the entire parameter space. Recent development of high-throughput methods opens the possibility to enhance these empirical structure maps by ab initio calculations in regions of the parameter space where the experimental evidence is lacking or not well characterized. In this paper we construct enhanced maps for the binary alloys of hcp metals, where the experimental data leaves large regions of poorly characterized systems believed to be phase separating. In these enhanced maps, the clusters of noncompound-forming systems are much smaller than indicated by the empirical results alone. © 2010 The American Physical Society.