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Multi-Agent Narrative Experience Management as Story Graph Pruning
Get PDFIn this thesis I describe a method where an experience manager chooses actions for non-player characters (NPCs) in intelligent interactive narratives through story graph representation and pruning. The space of all stories can be represented as a story graph where nodes are states and edges are actions. By shaping the domain as a story graph, experience manager decisions can be made by pruning edges. Starting with a full graph, I apply a set of pruning strategies that will allow the narrative to be finishable, NPCs to act believably, and the player to be responsible for how the story unfolds. By never pruning player actions, the experience manager can accommodate any player choice. This experience management technique was first implemented on a training simulation, where participants’ performance improved over repeated sessions. This technique was also employed on an adventure game where players generally found the NPCs’ behaviors to be more believable than the control
Working memory deficits are associated with altered regional brain volume and structural connectivity in children with chromosome 22q11.2 deletion syndrome.
Get PDFBackground: Children with chromosome 22q11.2 deletion syndrome (22q11.2DS) exhibit nonverbal learning disability that may manifest in part because of working memory (WM) deficits. 22q11.2DS is a complex developmental disorder with serious physical, learning, cognitive, and psychiatric symptoms including a risk of developing schizophrenia 30 times that of the general population. WM impairment likely contributes to and exacerbates learning difficulties, school problems, existing neuropsychological disorders such as attention deficit hyperactivity disorder (ADHD); and a poor WM may be a biological risk marker for future mental illness. WM impairment is established in this population, but less is known about its neurological origins.
Frontoparietal cortical development and function are key to WM processing. In the neurotypical developing brain, studies indicate activation associated with WM shifts from parietal to frontal regions with age. However, in children with 22q11.2DS, activation is restricted to the frontal cortex, and volumes are reduced in parietal regions where abnormal tractography abides. The overarching aim of this study was to determine the neural origins of WM impairment in people with 22q11.2DS.
Methods: We measured WM in children and adolescents with (n = 29) and without (n = 27) 22q11.2DS using the WISC-IV and a computer-based spatial working memory task (SWMT) task. Participants’ brains were scanned using high-resolution magnetic resonance imaging (MRI) and diffusion tensor imaging (DTI). Focusing on brain morphometry and structural connectivity within frontoparietal networks, we investigated neural underpinnings of WM processing in 22 children with 22q11.2DS and 19 typically developing (TD) controls ages 7 to 16 (M = 12.13 ± 2.41). A connectome mapping network involved in WM processing was constructed by superimposing cortical segmentations on white-matter tractography.
Results: Children with 22q11.2DS had impaired working memory performance. Individuals’ performance on our SWMT moderated the association between diagnosis and gray and white matter macro and microstructure. Children with 22q11.2DS with better working memory had larger lateral orbitofrontal volumes, greater axial diffusivity in the left superior frontal to superior parietal tract, and smaller volume in the right superior frontal to lateral orbitofrontal tract. Poorer performance in children with 22q11.2DS was associated with smaller right superior parietal and superior frontal cortical volumes.
Conclusions: Children with 22q11.2DS performed worse on measures of working memory. Their performance was related to regional cortical volume differences and white matter microstructure abnormalities in the frontal and parietal lobes. These are brain regions consistently implicated in WM processing
Evolution and stratigraphic architecture of tidal point bars with and without fluvial input: influence of variable flow regimes on sediment and facies distribution, and lateral accretion
Get PDFTide-influenced point bars represent a significant proportion of shallow-marine deposits, commonly developed along meandering channels in most backbarrier and estuarine systems. However, sedimentological studies to characterize this type of deposit are still emerging. They often present very heterogeneous internal architectures which development is controlled by the complex flow patterns operating in tidal environments. The study of the sedimentological and morphological characteristics of these features provides better understanding of the hydrodynamic processes that shape coastal systems and control their evolution as well as it contributes to better reservoir potential prediction and production strategy optimization, as tidal point bars may represent hydrocarbon reservoirs in subsurface and their heterogeneous characteristics directly impact reservoir quality. In this study, we investigated six modern tidal point bars located along distinct estuarine tidal channels in Georgia. Using core data, 2D shallow seismic data and current measurements and flow velocity profiles, we discussed the main hydrodynamic controls on sediment transport and distribution, and determined how they affect the morphology, the internal architecture and the sediment distribution within these bars. We confirmed that the influence of fluvial input in tidal channels plays an important role on the development of the morphology and the heterogeneous architecture of point bars as it adds more complexity to the system hydrodynamics, promoting more asymmetric variations in water level fluctuations and huge variations of current velocities. We proved that point bars developed in distinct tide-influenced channels and estuaries, although present very different sedimentary facies distribution, may have sedimentary facies in common, which organization is analogous to surface processes operating at each environment. We demonstrated that differences in tidal asymmetries between the ebb and flood channels produce sedimentological differences between the different parts of the bar. This study showed that tidal point bars present distinct heterogeneous sediment distributions, morphologies and internal architectures that do not conform to the existing theoretical models of fluvial point bars and highlighted that, despite the differences in local hydrodynamic conditions, similarities identified between the different bars permitted us to distinguish the sedimentological responses to regional allogenic events, which can be mistakenly interpreted as sedimentological responses to local autogenic events
Leisure and Labor in New Orleans\u27 Number One Factory : Work, Culture, and the Political Economy of Tourism
Get PDFAs the symbolic and functional heart of the New Orleans tourism industry, the French Quarter has been described as the city\u27s number one factory . Using this evocative image as a starting point, this paper explores workaday life within this factory. I argue that the political economy of tourism brings together the world of work and the world of leisure in such a way that neither can be meaningfully understood apart from each other. To get at this point, I examine the commodity which at the heart of the tourist economy, which, I contend, is the touristic experience. Drawing on data gleaned from interviews, participant observation, and analysis of tourist discourse, I show that the production of this commodity – immaterial as it may appear – is in fact quite labor intensive. Furthermore, as tourism has become the driving sector of the New Orleans economy, the social and economic arrangements that the industry entails have extended out from the factory, integrating a broader swath of the city\u27s geography into its structure than is generally supposed
Volatility Interruptions, idiosyncratic risk, and stock return
Get PDFThe objective of this paper is to examine the impact of implementing the static and dynamic volatility interruption rule on idiosyncratic volatility and stock returns in Nasdaq Stockholm. Using EGARCH and GARCH models to estimate the conditional idiosyncratic volatility, we find that the conditional idiosyncratic volatility and stock returns increase as stock prices hit the upper static or dynamic volatility interruption limits. Conversely, we find that the conditional idiosyncratic volatility and stock returns decrease as stock prices hit the lower static or dynamic volatility interruption limit. We also find that the conditional idiosyncratic volatility is higher when stock prices reach the upper dynamic limit than when they reach the upper static limit. Furthermore, we compare the conditional idiosyncratic volatility and stock returns on the limit hit days to the day before and after the limit hit events and find that the conditional idiosyncratic volatility and stock returns are more volatile on the limits hit days. To test the volatility spill-over hypothesis, we set a range of a two-day window after limit hit events and find no evidence for volatility spill-over one or two days after the limit hit event, indicating that the static and dynamic volatility interruption rule is effective in curbing the volatility. Finally, we sort stocks by their size and find that small market cap stocks gain higher returns than larger market cap stocks upon reaching the upper limits, both static and dynamic
A Space of Their Own Color: Black Greek Letter Organizations at the University of New Orleans
Get PDFEvery semester across the United States, countless students join Greek letter organizations. While some may recognize the Greek letters, many Americans do not know the racial divide within the Greek life system, and the difference of purpose those organizations hold. This study focuses on eight historically Black fraternities and sororities and more specifically, their chapters at the University of New Orleans, a university that throughout its history has had a predominantly White student body, and often fostered an environment overtly and subtly hostile to African-American students.
Using oral histories, university yearbooks, and university newspapers this study demonstrates how Black fraternities and sororities at UNO promoted and supported the academic success of African-American students by emphasizing community service work, communal bonds, and connections to campus activities. These organizations provided emotional and academic support for African-American students and actively resisted the racial divisiveness present on their university campus
Detection of Sand Boils from Images using Machine Learning Approaches
Get PDFLevees provide protection for vast amounts of commercial and residential properties. However, these structures degrade over time, due to the impact of severe weather, sand boils, subsidence of land, seepage, etc. In this research, we focus on detecting sand boils. Sand boils occur when water under pressure wells up to the surface through a bed of sand. These make levees especially vulnerable. Object detection is a good approach to confirm the presence of sand boils from satellite or drone imagery, which can be utilized to assist in the automated levee monitoring methodology. Since sand boils have distinct features, applying object detection algorithms to it can result in accurate detection. To the best of our knowledge, this research work is the first approach to detect sand boils from images. In this research, we compare some of the latest deep learning methods, Viola Jones algorithm, and other non-deep learning methods to determine the best performing one. We also train a Stacking-based machine learning method for the accurate prediction of sand boils. The accuracy of our robust model is 95.4%
Her People and Her History: How Camille Lucie Nickerson Inspired the Preservation of Creole Folk Music and Culture, 1888-1982
Get PDFOver the twentieth century, Camille Lucie Nickerson excelled in her multi-faceted career as an educator, musician, and interpreter for the advancement of musical education for generations of black students in New Orleans and at Howard University in Washington D.C. Nickerson devoted herself to furthering her musical education through private instruction with her father, Professor William J. Nickerson. She then graduated with a diploma from Southern University and with a B.A. and M.A. in music from Oberlin College. Nickerson’s leadership in musical associations on a local and national level enhanced her ability to reach audiences of all ages through her performances. She dedicated her life to musical education and the sharing Creole folk music, both personal attributes passed down from her father. While Nickerson was determined to preserve Creole folk music through her lecture-recitals, her wider purpose argued for a distinct recognition for Creole culture, thus, acknowledgment of her culture
Darwin or Frankenstein?
Get PDFThrough sculpture and drawing, I create my own versions of natural specimens primarily based upon the visual unity of disparate organisms. Invented specimens are composed using a variety of processes employing a mixture of atypical materials following the (20th, 21st century) Postmodern shift away from formalist and traditional uses of any singular medium. As well as a variety of art materials, the specimens are hybrids of organic and biomorphic elements, blurring boundaries between botanical, animal, fungal, metal, and mineral. Is my approach perhaps like Charles Darwin, observant and studious naturalist, or am I more like Dr. Frankenstein, science fiction maker of monstrosities
Scalable Community Detection using Distributed Louvain Algorithm
Get PDFCommunity detection (or clustering) in large-scale graph is an important problem in graph mining. Communities reveal interesting characteristics of a network. Louvain is an efficient sequential algorithm but fails to scale emerging large-scale data. Developing distributed-memory parallel algorithms is challenging because of inter-process communication and load-balancing issues. In this work, we design a shared memory-based algorithm using OpenMP, which shows a 4-fold speedup but is limited to available physical cores. Our second algorithm is an MPI-based parallel algorithm that scales to a moderate number of processors. We also implement a hybrid algorithm combining both. Finally, we incorporate dynamic load-balancing in our final algorithm DPLAL (Distributed Parallel Louvain Algorithm with Load-balancing). DPLAL overcomes the performance bottleneck of the previous algorithms, shows around 12-fold speedup scaling to a larger number of processors. Overall, we present the challenges, our solutions, and the empirical performance of our algorithms for several large real-world networks