The nature of modern mathematics: inaugural lecture delivered at Rhodes University

Inaugural lecture delivered at Rhodes UniversityRhodes University Libraries (Digitisation) iiidc:provenanc

J.R.R. Tolkien, Fanfiction, and The Freedom of the Reader

Student paper award, Mythcon 2013. Abrahamson makes a particularly convincing case for the validity of fanfiction by applying Tolkien’s own statements about the “dominion of the author,” the “Cauldron of Story,” and subcreation to the issue. Discusses Tolkien’s experiences with early fanwork and his own use of sources as an author

Medieval romance, fanfiction, and the erotics of shame

My dissertation uses fan studies theories of fanfiction to reframe later medieval romances as works that were not only reread and rewritten, but transformed through affective reading and rewriting strategies, especially through desire and shame. I explore the erotics of shame through fanfiction tropes seen in a variety of canonical and non-canonical medieval romances, both Arthurian and otherwise, from the twelfth century to the fifteenth. I use elements that function as major motifs in fanfiction, in spite or even because of their embarrassing nature, including fanfiction's predominantly female authorship and its catering to queer desires, the prevalence of male/male romantic storylines (slash), the focus on rendering male bodies vulnerable through hurt and comfort, and fanfiction's embrace of a variety of erotic kinks which may remain fantasy desires only. By locating fanfiction desires and shames in medieval romance, I reveal modes of resistance to structures of hegemony through the tactic of finding personal pleasure in the culturally shameful. The ways in which fanfiction challenges heteronormative ideologies of gender and sexuality highlights ways in which medieval romances press on these boundaries, too

Situating multimodal learning analytics

The digital age has introduced a host of new challenges and opportunities for the learning sciences community. These challenges and opportunities are particularly abundant in multimodal learning analytics (MMLA), a research methodology that aims to extend work from Educational Data Mining (EDM) and Learning Analytics (LA) to multimodal learning environments by treating multimodal data. Recognizing the short-term opportunities and longterm challenges will help develop proof cases and identify grand challenges that will help propel the field forward. To support the field's growth, we use this paper to describe several ways that MMLA can potentially advance learning sciences research and touch upon key challenges that researchers who utilize MMLA have encountered over the past few years

The Computational Complexity of the Game of Set and its Theoretical Applications

The game of SET is a popular card game in which the objective is to form Sets using cards from a special deck. In this paper we study single- and multi-round variations of this game from the computational complexity point of view and establish interesting connections with other classical computational problems. Specifically, we first show that a natural generalization of the problem of finding a single Set, parameterized by the size of the sought Set is W-hard; our reduction applies also to a natural parameterization of Perfect Multi-Dimensional Matching, a result which may be of independent interest. Second, we observe that a version of the game where one seeks to find the largest possible number of disjoint Sets from a given set of cards is a special case of 3-Set Packing; we establish that this restriction remains NP-complete. Similarly, the version where one seeks to find the smallest number of disjoint Sets that overlap all possible Sets is shown to be NP-complete, through a close connection to the Independent Edge Dominating Set problem. Finally, we study a 2-player version of the game, for which we show a close connection to Arc Kayles, as well as fixed-parameter tractability when parameterized by the number of rounds played

Telesat-G/Delta post launch report

The Canadiari Telesat-G (ANIK-D1) commercial communications satellite was launched successfully from the Eastern space and Missile Center (ESMC) at 7:10 p.m., EDT, on August 25, 1982, by a Delta 3920 Vehicle, Mission Number 164. Performance of the two stage Delta launch vehicle was nominal and placed the payload in a low circular orbit as planned. The Payload Assist Module (PAM-D), which is part of the payload, also performed nominally. The synchronous transfer orbital elements achieved by Delta/PAM, compared with the nominal expected, are provided. The satellite performed satisfactorily during the transfer orbit, and the ABM was fired successfully at 5:29 p.m., EDT, on August 29, 1982. The satellite was maneuvered to a position 104 degrees West Longitude above the equator. Satellite status is satisfactory and it has entered service

A methodology for the estimation of kappa (κ) for large datasets. Example application to rock sites in the NGA-East database

This report reviews four of the main approaches (two band-limited and two broadband) currently used for estimating the site κ0: the acceleration slope (AS) above the corner frequency, the displacement slope (DS) below the corner frequency, the broadband (BB) fit of the spectrum, and the response spectral shape (RESP) template. Using these four methods, estimates of κ0 for rock sites in Central Eastern North America (CENA) in the shallow crustal dataset from NGAEast are computed for distances less than 100 km. Using all of the data within 100 km, the mean κ0 values are 8 msec for the AS approach and 27 msec for the DS approach. These mean values include negative κ estimates for some sites. If the negative κ values are removed, then the mean values are 25 msec and 42 msec, respectively. Stacking all spectra together led to mean κ0 values of 7 and 29 msec, respectively. Overall, the DS approach yields 2–3 times higher values than the AS, which agrees with previous observations, but the uncertainty of the estimates in each case is large. The AS approach seems consistent for magnitudes down to M3 but not below. There is large within-station variability of κ that may be related to differences in distance, Q, complexity along the path, or particular source characteristics, such as higher or lower stress drop. The station-to-station differences may be due to site-related factors. Because most sites have been assigned Vs30 = 2000 m/sec, it is not possible to correlate variations in κ0 with rock stiffness. Based on the available profile, the individual spectra are corrected for crustal amplification and only affect results below 15 Hz. Since the AS and DS approaches are applied over different frequency ranges, we find that only the DS results are sensitive to the amplification correction. More detailed knowledge of individual near-surface profiles may have effects on AS results, too. Although κ is considered to be caused solely by damping in the shallow crust, measurement techniques often cannot separate the effects of damping and amplification, and yield the net effect of both phenomena. The two broadband approaches, BB and RESP, yield similar results. The mean κ0_BB is 5±0.5 msec across all NEHRP class A sites. The κ0_RESP for the two events examined is 5 and 6 msec. From literature, the average value of κ0 in CENA is 6 ± 2 msec. This typical value is similar to the broadband estimates of this study and to the mean κAS when all available recordings are used along with all flags. When only recordings with down-going FAS slope are selected from the dataset, the mean value of κAS increases by a factor of 2–3. To evaluate the scaling of high-frequency ground motion with κ, we analyze residuals from ground motion prediction equations (GMPEs) versus κ estimates. Using the κ values from the AS approach, the average trend of the ln(PSA) residuals for hard-rock data do not show the expected strong dependence on κ, but when using κ values from the DS approach, there is a stronger correlation of the residuals, i.e., a κ that is more consistent with the commonly used analytically based scaling. The κDS estimates may better reflect the damping in the shallow crust, while the κAS estimates may reflect a net effect of damping and amplification that has not been decoupled. The κDS estimates are higher than the κAS estimates, so the expected effect on the high-frequency ground motion is smaller than that expected for the κAS estimates. An empirical hard-rock site factor model is developed that represents the combined Vs-κ0 site factor relative to a 760 m/sec reference-site condition. At low frequencies ( 10 Hz), the residuals do not show the strong increase in the site factors as seen in the analytical model results. A second hard-rock dataset from British Columbia, Canada, is also used. This BC hard-rock residuals show an increase in the 15–50 Hz range that is consistent with the analytical κ0 scaling for a hard-rock κ0 of about 0.015 sec. The variability of the PSA residuals is also used to evaluate the κ0 scaling for hard-rock sites from analytical modeling. The scatter in existing κ0 values found in literature is disproportionately large compared to the observed variability in high-frequency ground motions. We compared the predicted ground-motion variability based on analytical modeling to the observed variability in our residuals. While the hard-rock sites are more variable at high frequencies due to the additional κ0 variability, this additional variability is much less than the variability predicted by the analytical modeling using the variability from κ0-Vs30 correlations. This is consistent with weaker κ0 scaling compared to that predicted by the analytical modelling seen in the mean residuals

Squeezing Kappa (κ) out of the transportable array: A strategy for using bandlimited data in regions of sparse seismicity

The κ parameter (Anderson and Hough, 1984), and namely its site-specific component (κ0), is important for predicting and simulating high-frequency ground motion. We develop a framework for estimating κ0 and addressing uncertainties under the challenging conditions often imposed in practice: 1. Low seismicity (limited, poor-quality, distant records); 2. Limited-bandwidth data from the Transportable Array (maximum usable frequency 16 Hz); 3. Low magnitudes (ML1.2-3.4) and large uncertainty in stress drop (corner frequency). We cannot resolve stress drop within the bandwidth, so we propose an approach that only requires upper and lower bounds on its regional values to estimate κ0. To address uncertainties, we combine three measurement approaches (acceleration spectrum slope, AS; displacement spectrum slope, DS; broadband spectral fit, BB). We also examine the effect of crustal amplification, and find that neglecting it can affect κ0 by up to 35%. DS estimates greatly exceed AS estimates. We propose a reason behind this bias, related to the residual effect of the corner frequency on κAS and κDS. For our region, we estimate a frequency-independent mean S-wave Q of 900±300 at 9-16 Hz, and an ensemble mean κ0 over all sites of 0.033±0.014 s. This value is similar to the native κ0 of the NGA-West2 ground motion prediction equations, indicating that these do not need to be adjusted for κ0 for use in Southern Arizona. We find that stress drop values in this region may be higher compared to estimates of previous studies, possibly due to trade-offs between stress drop and κ0. For this dataset, the within-approach uncertainty is much larger than the between-approach uncertainty, and it cannot be reduced if the data quality is not improved. The challenges discussed here will be relevant in studies of κ for other regions with band-limited data, e.g., any region where data come primarily from the TA

Dispelling the myths of online education: learning via the information superhighway

There continues to be a perception that online education is inferior to traditional education. In the U.S. online learning is more developed than in the U.K. This paper provides insights into a U.S. provision and takes a close look at what are perceived as weaknesses of on line learning and argues that these are not necessarily inherent weaknesses of this form of educational delivery. Then, results of two major studies, undertaken in the U.S. are provided comparing the effectiveness of online education to traditional education as perceived by current MBA students and past graduates. Results of these studies suggest that students of MBA modules and MBA graduates perceive the quality and effectiveness of online education to be similar to, if not higher than, the quality and effectiveness of traditional modules and programmes

Habitat Evaluation Procedures (HEP) Report : Grand Coulee Dam Mitigation, 1996-1999 Technical Report.

The purpose of this Habitat Evaluation Procedures (HEP) study was to determine baseline habitat units and to estimate future habitat units for Bonneville Power Administration (BPA) mitigation projects on the Spokane Indian Reservation. The mitigation between BPA and the Spokane Tribe of Indians (STOI) is for wildlife habitat losses on account of the construction of Grand Coulee Dam. Analysis of the HEP survey data will assist in mitigation crediting and appropriate management of the mitigation lands