2,254 research outputs found
Generalized Arrow Update Logic
No full textBarteld Kooi and Bryan Renne (2011). Generalized Arrow Update Logic. In K.R. Apt (editor). Theoretical Aspects of Rationality and Knowledge, Proceedings of the Thirteenth Conference (TARK 2011), pp. 205-211.
Generalized Arrow Update Logic
No full textBarteld Kooi and Bryan Renne (2011). Generalized Arrow Update Logic. In K.R. Apt (editor). Theoretical Aspects of Rationality and Knowledge, Proceedings of the Thirteenth Conference (TARK 2011), pp. 205-211
Video observations of rip currents on an embayed beach
No full textRip currents and their interaction with waves and underwater morphology are still poorly understood. This study presents a conceptual model demonstrating how rip channels respond to changes in wave conditions, focusing on wave energy and wave event duration. Past attempts to relate rip channels to wave conditions have not resulted in good relationships between rip characteristics (e.g. rip spacing) and waves. In order to address this problem, a 3.3 year rip channel data set was obtained using an improved computer-based technique to locate rips from video imagery. In this study we show how the scale of rip channels (i.e. cross-shore extent ), previous wave conditions and the duration of high wave events determine how rip channels will evolve. Observations of six events when rip channels changed their spatial configuration are used to create a conceptual model for how rip channels respond to changes in the wave conditions. When rip channels are small in relation to the wave energy, these rips are more likely than larger rips (extending less than ~70m cross-shore) to evolve. Conversely when rip channels are large in relation to the wave energy, these rips are less likely to evolve than smaller rips (extending more than ~80 m cross-shore)
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COVID-19 Interview with Bryan Caplan
No full textA discussion on the COVID-19 pandemic with Bryan Caplan, an economist from George Mason University as well as the author of "The Case Against Education" and "Open Borders."Salem Cente
A numerical model to simulate the formation and subsequent evolution of tidal channel networks
No full textWe present a numerical model that simulates morphological change as a result of the interactions between hydrodynamics, sediment transport and bed elevation change. Numerical simulations indicate that these morphodynamic interactions can lead to the initiation of tidal channels and potentially give rise to large-scale channel networks. We perform a sensitivity analysis to show how model outcome is sensitive to the numerical scheme adopted, hydrodynamic and morphological time-steps, and initial bathymetry. Furthermore, the formation of tidal channels and intertidal areas affects both the large-scale flow patterns, as well as the asymmetry between flood- and ebb-tidal currents<br/
Sharon Bryan 03-15-1990
No full textReading List
"Breaking and Entering" from "Objects of Affection" (0:35)
"Viewing the Body" "from Salt Air" (16:08)
"Theory" from "Flying Blind: Poems" (38:27)
"Trimmings" from "Flying Blind: Poems" (39:47)
Abstract
Sharon Bryan Reads "Breaking and Entering" from "Objects of Affection" (0:35). Stan Saville Rubin interviews Sharon Bryan. Bryan was born in Salt Lake City, Utah and educated at the University of Utah where she studied philosophy, Cornell University where she received an MA in anthropology, and The University of Iowa Writers Workshop where she earned her MFA. She's the author of two collections of poetry, "Salt Air" published in 1983, and "Objects of Affection" published in 1987 by Wesleyan University Press. She has received awards including The Academy of American Poets Prize, the Discovery the Nation Award, and the Governor's Award from the State of Washington, and has held NEA fellowships. At the time of filming Bryan is a Professor of English at the Memphis State University and editor of the literary magazine River City. Stan opens the conversation with an invitation to discuss the origin and nature of the opening poem. Bryan outlines the story and the influences that aided her creation of the poem. Expanding further into the content of "Objects of Affection", they discuss the heavy handed artistic and literary influences that are found in a number of the collected poems. Bryan talks about why the unaddressed epitaph is at the beginning of "Objects of Affection" and what informed her decision to put it there. Stan asks her about the careful organization of the collection but Bryan reveals that the organization wasn't as deeply considered as it appears. They talk about the style of her poems and how she tends not to use prose. Stan moves the conversation to "Salt Air" which was written 6 years after leaving Iowa. Bryan talks about how so much of her life was leaving behind Salt Lake. Bryan reads "Viewing the Body" "from Salt Air" (16:08). Bryan speaks on when she first knew she wanted to write and how she meandered through her education because, as far as she was aware, creative writing as an occupation wasn't available until she had arrived at Cornell and then why she chose to go to the Iowa Writers Workshop. Stan asks Bryan to speak at length about her role as Editor of the River City literary magazine and how she looks at poetry through that editor's lens. They discuss the social significance of poetry and address critiques about poetry's place for speaking on difficult issues of the time. Bryan talks about the major influences on her writing and her push to publish her poetry for public consumption and how she found out her first collection was going to be printed. Bryan reads "Theory" from her upcoming collection of poems "Flying Blind: Poems" (38:27) and "Trimmings" also from "Flying Blind: Poems" (39:47).Archived web conten
Modelling the effects of tidal range and initial bathymetry on the morphological evolution of tidal embayments
No full textTidal embayments are characterized by a wide variety of landscape features, often including either complex tidal channel networks or extensive flood-tidal deltas. The origin of these features and the influence of hydrodynamic drivers and initial geological setting on their long-term characteristics are essentially unexplored. A model was applied to simulate the long-term morphological evolution of tidal embayments, with the purpose of providing insight into the environmental conditions that lead to the differences in tidal embayment morphology. Numerical simulations indicated that the interaction between hydrodynamics, sediment transport, and the evolving topography gives rise to the formation of channel networks. The tidal range and the depth of the initially unchannelized tidal basin controlled the way in which the morphology evolved and determined the timescale over which channels and intertidal areas developed. Channel network formation occurred more rapidly when the tidal range increased and/or when the initial basin depth decreased. Tidal basins with a large initial depth showed the development of a flood-tidal delta and for these deep basins channel incision could remain absent over long timescales. Both tidal range and initial bathymetry affected final basin hypsometry and channel network characteristics, including the channel density and the fraction of the basin occupied by the channels. All the simulated morphologies, with different combinations of the tidal range and depth of the basin, evolved towards a state of less morphodynamic activity for which the relative intertidal area was proportional to the ratio of tidal amplitude to basin depth<br/
JCCC Hosts \u27Public Enemies\u27 Author, Bryan Burrough
No full textBest-selling author Bryan Burrough will present \u27Public Enemies: The True Story\u27 at 11 a.m. Monday, November 2, in Craig Community Auditorium
Observations of rip channels, sandbar-shoreline coupling and beach rotation at Tairua beach, New Zealand
No full textInterannual wave climate variations along the north east coast of New Zealand have caused significant changes to the erosional state of many of the popular tourist beaches. These changes threaten property, ruin expensive and labour-intensive dune plantings and destabilise walkways. The alongshore spatial and temporal variation of erosion can, however, not always be directly dependant on the variability in the wave climate. The response appears to be dependant on the alongshore extent of the beach and the existence of headlands. This work takes a 3.4 year data-base of rip channel location, sandbar position and shoreline position to quantify the patterns that occur on a headland-controlled embayed beach. Findings show that when wave events had a strong alongshore component, the alongshore bar and shoreline rotated and three dominant, persistent, rip channels developed on the end of the beach at which both the shoreline and barline were more seaward. This pattern where the beach rotated in one direction occurred on three occasions: at the beginning of the dataset (early 1999), during the persistent small storms during the winter of 2000, and in the other direction during the large storm in mid 2001. The rotation events were clearly related to the dominance of northward versus southward alongshore flux events over 3500 J/m2. These results show that on embayed beaches, the alongshore wave energy flux is pivotal in controlling shoreline erosion and the severity and location of rip channels
Modeling the morphodynamic response of tidal embayments to sea-level rise
No full textSea-level rise has a strong influence on tidal systems, and a major focus of climate change effect studies is to predict the future state of these environmental systems. Here, we used a model to simulate the morphological evolution of tidal embayments and to explore their response to a rising sea level. The model was first used to reproduce the formation of channels and intertidal flats under a stable mean water level in an idealised and initially unchannelled tidal basin. A gradual rise in sea level was imposed once a well-developed channel network had formed. Simulations were conducted with different sea-level rise rates and tidal ranges. Sea-level rise forced headward erosion of the tidal channels, driving a landward expansion of the channel network and channel development in the previously non-inundated part of the basin. Simultaneously, an increase in channel drainage width in the lower part of the basin occurred and a decrease in the overall fraction of the basin occupied by channels could be observed. Sea-level rise thus altered important characteristics of the tidal channel network. Some intertidal areas were maintained despite a rising sea level. However, the size, shape, and location of the intertidal areas changed. In addition, sea-level rise affected the exchange of sediment between the different morphological elements. A shift from exporting to importing sediment as well as a reinforcement of the existing sediment export was observed for the simulations performed here. Sediment erosion in the inlet and the offshore transport of sediment was enhanced, resulting in the expansion of the ebb-tidal delta. Our model results further emphasise that tidal embayments can exhibit contrasting responses to sea-level rise.<br/
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