What Comes to the Surface: Storms, Bodies and Community in Jesmyn Ward’s Salvage the Bones

What comes to the surface: storms, bodies and community in Jesmyn Ward's 'Salvage the Bones

Decentralized Robust Control of Robot Manipulators with Harmonic Drive Transmission and Application to Modular and Reconfigurable Serial Arms

In this paper, we propose a decentralized robust control algorithm for modular and reconfigurable robots (MRRs) based on Lyapunov’s stability analysis and backstepping techniques. In using decentralized control schemes with robot manipulators, each joint is considered as an independent subsystem, and the dynamical effects from the other links and joints are treated as disturbance. However, there exist many uncertainties due to unmodeled dynamics, varying payloads, harmonic drive (HD) compliance, HD complex gear meshing mechanisms, etc. Also, while the reconfigurability of MRRs is advantageous, modifying the configuration will result in changes to the robot dynamics parameters, thereby making it challenging to tune the control system. All the above mentioned disturbances in addition to reconfigurability present a challenge in controlling MRRs. The proposed controller is well-suited for MRR applications because of its simple structure that does not require the exact knowledge of the dynamic parameters of the configurations. Desired tracking performance can be achieved via tuning a limited set of parameters of the robust controller. If the numbers of degrees of freedom are held constant, these parameters are shown to be relatively independent of the configuration, and can be held constant between changes in configuration. This strategy is novel compared to existing MRR control methods. In order to validate the controller performance, experimental setup and results are also presented

Queer transcultural memory: contemporary US culture and the global context

This thesis expands the definition of queerness through exploring its oppositionality to norms of heteronormativity tied to race, class, gender, sexuality, and disability. Reading an interdisciplinary range of cultural texts, I consider the extent to which they can be deployed to provide a counternarrative to concepts of transcultural memory, nationalism, and citizenry following recent historical events, stemming from September 11, 2001. I begin by examining the impact of domestic responses to 9/11 through “vernacular” photography, demonstrating how nationalistic responses marginalize queer identities. Expanding out to explore the transnational effects of the “War on Terror”, my second chapter reads contemporary Iraq War fiction, revealing the queer rendering of bodies that finds a foothold through military occupations abroad. Third, I look to the extra-national sites of Guantánamo Bay and Abu Ghraib to show the insidious extension of national borders, and norms, creating sites that are simultaneously intra- and extra-national. I argue that these sites operate as palimpsests of memory, crossing frontiers of the transnational, transcultural, and transhistorical. Finally, I look at the movement of queer bodies into the United States through migration narratives, returning to the ubiquitous sites of normativity within the country’s borders. My conclusion ties these strands together to understand how memorialization and cultural representations of historical events impact queer bodies and the cultural conditions of the US. I establish how these bodies affect, and are affected by, literal, figurative, and imaginative movements, and the implications for state discourse. Ultimately, I demonstrate the “Americanization” of globalization dictates how such bodies are conceptualized and is subsequently treated in other nations

Whale Voices from the Deep: Temporal Patterns and Signal Structures as Adaptations for Living in an Acoustic Medium

Abstract: Whales produce long, rhythmic patterns of sounds and their low-frequency sounds (< 100 Hz) can travel many hundreds of miles underwater. Each species' signals are distinguishable acoustically by temporal features but there has been a history of infatuation with melodic qualities as the primary features of measurement. Temporal rates and time-bandwidth products are generally related to bathymetry and transmission properties, suggesting that signal features are adapted for communication and navigation. Pelagic species such as blue and fm whales rely on signals in the IO-30 Hz band, presumably to take advantage of the excellent lowfrequency propagation properties of the deep ocean, with lo-200 s patterns of sound delivery. The cadence of signal delivery for blue and fin whales is such that an individual retains the rhythm of the delivery after minutes of silence. Shallow water species produce mid-frequency signals (50-1000 Hz) with temporal patterns on the order of seconds. These species with faster rhythms have greater signal variability covering a greater range of frequencies. Animal acoustic production and perception systems are determined and constrained in ways that are quite different than those in an engineered system. Although certain components of the engineering -biological communication analogy have value (e.g. the basic complement of sender, channel, and receiver) the evolutionary constraints imposed by natural and sexual selection and the central role of variability in the selection process result in biological communication systems that are poorly modeled using traditional engineering perspectives. Likewise, it is tempting to interpret features of a biological system (e.g., signal complexity) as though they were optimizing an engineering parameter when in fact they are most probably evolved under the highly non-linear forces of selection. In some cases, can one expect to find bioacoustic features well mapped by the constraints of physical acoustics. Thus, for example, alarm calls in birds are selected to have features than render them difficult to locate but easy to detect (i.e., loud and audible, but with very little bandwidth; Marler 1955), or long range calls in blue whales have features that make them detectable over extremely long ranges (i.e. very loud, infrasonic, narrowband and redundant). One acoustic dimension often overlooked in quantitative analysis of animal acoustic signaling behavior is rhythmicity, especially when frequency or amplitude modulations are dominant salient features of the signal. For the two species of whales that are known to produce very loud, long patterns of infrasonic signals, this is not the case since variability in signal structure is low and rhythm is the most salient acoustic feature. Thesc blue and fin whale sounds are well matched to the acoustic environment, especially the deep sound channel, leading to speculation that communication could occur over extremely loud distances on the order of hundreds of miles (Payne and Webb, 197 1). Recent advances in acoustic propagation modeling and empirical measurements raise the possibility that these animals could use their infrasonic signals to detect gross bathymetric features such as seamounts, continental shelves and mid-ocean ridges in a form of low-frequency navigation. In this case temporal stability could be more important than FM variability. These fairly simple levels of acoustic variability for pelagic species are in dramatic contrast to species, such as bowhead, humpback or right whales that inhabit coastal areas during breeding, calving or migration. For these species, temporal stability is diminished while frequency bandwidth and variability are increased (se

Reimagining the American Landscape: Queer Topographics in Nina Berman's Homeland

This article argues that Nina Berman’s Homeland (2008) is a rearticulation of the US domestic landscape following 9/11. The book excavates and shapes cultural memory through image and text by examining how parts of the country responded to the 2001 events. Considering how Homeland captures what I call queer topographics of US culture, I suggest that the spaces of the everyday are mediated by Berman’s framing and use of “narrative” essays, disrupting the heteronormativity of a populist rhetoric that seeks to exclude difference. Homeland ultimately offers viewers the opportunity to further redefine the US landscape through queerness