The Afterlives of Frantz Fanon and the Reconstruction of Postcolonial Studies

This essay mobilizes Fanon as a point of entry into mapping the current state of postcolonial studies, and within that, reflects on what constitutes the postcolonial canon. Over a gradual course of the eighties and nineties, there has come about a transition from the field’s founding moments in which anti-imperialism, tricontinentalism, Third World nationalism and aesthetics of realism and resistance thrived, to the current trends that show a slant toward postmodernist fragmentation, multiculturalism, issues of diaspora, metropolitan narratives as well as a proclivity toward theorizing the field itself. There are many reasons for this: the specific dynamics of the post-Cold War American culture within which these works were received; the compromised relationship between academic and commercial publishing culture, which made a jump from narratives of decolonization and neocolonialism to metropolitan multiculturalism; and the sway of postmodernism over academia as a whole, which led to a disregard for Marxist theories and, more importantly, to a neglect of realism as a mode and aesthetic in postcolonial theory. These factors have worked together to shape how the genealogy of postcolonial studies and its theory have come to be accepted as “obvious.” This has, in turn, had strong repercussions for the kind of literature and theory that have come to be celebrated and canonized within the field. The essay draws on Anthony Alessandrini's Frantz Fanon and the Future of Cultural Politics: Finding Something Different (2014) and Neil Lazarus' The Postcolonial Unconscious (2011) to offer a reconstructed genealogy of the field of postcolonial studies.

The study of a model for via transition and the multi-layer via transition tool GUI design

One of the many challenges faced by engineers working with the present design scenario is to estimate the extent to which a signal, with significant high frequency content, is affected when it is routed on a printed circuit board. The printed circuit board routing will include the transition through the geometries like micro-strip or strip-line transmission lines, via transitions, and irregularities or asymmetries in the aforementioned geometries. One of these discontinuities, the via transition, results in the interaction of the signal on the via and the cavity (plane-pair) through which it passes. The via transition modeling will help characterize a block in the signal path. Section 1 explains the cavity model, and derives an expression for the impedance at a port in a rectangular cavity. The via to cavity connection, and the via capacitance calculation is explained. Then, five practical examples are used to show the model assembly in a circuit fashion, and the results are compared to the measurements. This modeling approach has been automated and integrated into the Multilayer Via Transition Tool, a tool that models all the common PCB geometries and provides the results as network parameters for the user defined ports. This tool is used for performance analysis and design optimization for the high speed PCBs. The tool includes a basic graphic user interface and an engine. Section 2 explains the design methodology for the provided graphic user interface. It explains interface design from the basic set of user inputs required by the engine to run. This section also talks about the difficulties in implementing the interface, and the required improvements for a professional tool --Abstract, page iii

Printed circuit board power distribution network modeling, analysis and design, and, statistical crosstalk analysis for high speed digital links

High-speed digital systems are moving to higher data rates and smaller supply voltages as the scale of integration goes smaller. With the smaller bit periods and the smaller operating voltages, the tolerable timing and noise margins are reducing. There are many sources of disturbances contributing to the tolerance margins. These margins have to account for inter symbol interference (ISI), reflections, jitter, noise from power distribution networks (PDN) and crosstalk. An important task during the design phase of the system is to find and mitigate the noise from such sources. This thesis proposes modeling and analysis methodology to resolve some of the problems while proposing relevant design methodologies to reduce the system design cycles. PDN design forms a critical part of a high-speed digital design to provide a low-noise power supply to the integrated circuits (ICs) within some peak voltage ripple for normal functioning. Switching of transistors in the IC leads to a high-frequency current draw and generates the simultaneous switching noise (SSN), which propagates along the PDN from the chip to the PCB and causes several EMI and SI problems. A physics-based modeling approach for PCB PDN is proposed which is used for analysis and design guideline development. A design methodology is developed which guides the designer to make better design decisions, knowing the impact on PDN performance without the use of full-wave tools. Crosstalk forms a critical part of the budget, and if ignored, can lead to design failures. A statistical method to find the distribution of crosstalk at the victim using the single bit response principle is proposed. The methodology is extended to multiple-aggressor system, and, can be used to identify worst case crosstalk and find dominant crosstalk contributors in a system. --Abstract, page iii

Towards a universal criteria for turbulence suppression in dilute turbidity currents with non-cohesive sediments

Turbidity currents exhibit fascinating physics as their sustained propagation depends on a tight interplay between the suspended sediments and turbulence. If resuspension dominates over deposition the intensity of the flow will increase, while if deposition dominates the flow turbulence can be completely damped inducing rapid settling of sediments and, eventually, flow extinction. This work explores the phenomenon whereby turbulence in a dilute turbidity current with non-cohesive sediments is abruptly extinguished owing to increasedsuspended sediment stratification.  Three parameters control the flow dynamics: Reynolds number (Re_t), Richardson number (Ri_t) and sediment settling velocity (V_z). The condition for complete turbulence suppression can be expressed as a critical value for Ri_t V_z. Based on simulations, limited experiments and limited field data, the critical value appears to have a logarithmic dependence on Re_t.Fil: Cantero, Mariano Ignacio. Comisión Nacional de Energía Atómica. Gerencia del Área de Energía Nuclear. Instituto Balseiro. Archivo Histórico del Centro Atómico Bariloche e Instituto Balseiro | Universidad Nacional de Cuyo. Instituto Balseiro. Archivo Histórico del Centro Atómico Bariloche e Instituto Balseiro; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte; ArgentinaFil: Shringarpure, Mrugesh. University of Florida; Estados UnidosFil: Balachandar, S.. University of Florida; Estados Unido

Direct N-body Kernels for Multicore Platforms

Abstract—We present an inter-architectural comparison of single- and double-precision direct n-body implementations on modern multicore platforms, including those based on the Intel Nehalem and AMD Barcelona systems, the Sony-Toshiba-IBM PowerXCell/8i processor, and NVIDIA Tesla C870 and C1060 GPU systems. We compare our implementations across platforms on a variety of proxy measures, including performance, coding complexity, and energy efficiency. I

Dynamics of complete turbulence suppression in turbidity currents driven by monodisperse suspensions of sediment

Turbidity currents derive their motion from the excess density imposed by suspended sediments. The settling tendency of sediments is countered by flow turbulence, which expends energy to keep them in suspension. This interaction leads to downward increasing concentration of suspended sediments (stable stratification) in the flow. Thus in a turbidity current sediments play the dual role of sustaining turbulence by driving the flow and damping turbulence due to stable stratification. By means of direct numerical simulations, it has been shown previously that stratification above a threshold can substantially reduce turbulence and possibly extinguish it. This study expands the simplified model by Cantero et al. (J. Geophys. Res., vol.114, 2009a, C03008), and puts forth a proposition that explains the mechanism of complete turbulence suppression due to suspended sediments. In our simulations it is observed that suspensions of larger sediments lead to stronger stratification and, above a threshold size, induce an abrupt transition in the flow to complete turbulence suppression. It has been widely accepted that hairpin and quasi-streamwise vortices are key to sustaining turbulence in wall-bounded flows, and that only vortices of sufficiently strong intensity can spawn the next generation of vortices. This auto-generation mechanism keeps the flow populated with hairpin and quasi-streamwise vortical structures and thus sustains turbulence. From statistical analysis of Reynolds stress events and visualization of flow structures, it is observed that settling sediments damp the Reynolds stress events (Q2 events), which means a reduction in both the strength and spatial distribution of vortical structures. Beyond the threshold sediment size, the existing vortical structures in the flow are damped to an extent where they lose their ability to regenerate the subsequent generation of turbulent vortical structures, which ultimately leads to complete turbulence suppression.Fil: Shringarpure, Mrugesh. University of Florida; Estados UnidosFil: Cantero, Mariano Ignacio. Comisión Nacional de Energía Atómica. Gerencia del Área de Energía Nuclear. Instituto Balseiro. Archivo Histórico del Centro Atómico Bariloche e Instituto Balseiro | Universidad Nacional de Cuyo. Instituto Balseiro. Archivo Histórico del Centro Atómico Bariloche e Instituto Balseiro; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte; ArgentinaFil: Balachandar, S.. University of Florida; Estados Unido

Prevalence of Vitamin D3 deficiency among pediatric patients with idiopathic nephrotic syndrome in remission - A cross-sectional observational study from Vadodara, Gujarat

Background: Vitamin D deficiency occurs in nephrotic syndrome (NS) through various mechanisms, resulting in loss of both, Vitamin D binding protein and 25-(OH) D, in the urine leading to the risk of bone disorders. Objectives: The objectives of the study were to detect the prevalence of Vitamin D deficiency in children with idiopathic NS during remission. Methods: This study was conducted from April to November 2016 at the pediatric nephrology clinic at a tertiary care hospital in Vadodara. A total of 34 children were enrolled with idiopathic NS in remission, of which 14 had first attack of NS and ten of Frequently Relapsing Nephrotic Syndrome (FRNS) and Infrequently Relapsing Nephrotic Syndrome each. Vitamin D levels were measured using serum levels of 25-(OH) D by chemiluminescence method. Results: Vitamin D deficiency was observed in 28 of 34 (82%) children; of which, 16 (47%) had severe deficiency and 12 (35.2%) had mild to moderate deficiency. Children with the first attack of NS had a median Vitamin D level of 8.17 ng/ml (interquartile range [IQR] 2.9–28), IFRNS had a median of 6.8 ng/ml (IQR 2.9–33), and FRNS had the lowest median of 5.3 ng/ml (IQR 2.9–16). Although there were differences among all the 3 groups, differences were not statistically significant (Kruskal–Wallis 4.89, p=0.08) which showed decreased levels of Vitamin D. Conclusion: High prevalence of Vitamin D deficiency was observed in all 3 groups of idiopathic NS; the lowest being in FRNS. There was no significant association with lower levels of Vitamin D and relapses in NS. More research is needed to assess Vitamin D deficiency and to ensure the effect of Vitamin D supplementation for children with NS

Entrainment in temporally evolving turbidity currents

Turbidity currents are sediment laden shear flows that run along a sloping bed, often sub- merged beneath a deep layer of quiescent fluid, driven by the excess hydrostatic pressure due to the suspended sediments. Turbidity currents are always turbulent since the suspended sediment particles that drive the flow cannot remain in suspension under laminar conditions. As the turbidity current travels downslope, the flow interacts with the bed at the bottom and with the ambient fluid layer at the top. Ambient fluid entrainment is a fascinating fluid mechanical phenomenon where quiescent ambient fluid is ingested into the current to an active shear flow. As the turbidity current flows downstream over the sloping bed, under a deep ambient of clear fluid, clear ambient fluid is continuously entrained into the turbidity current and the thickness of the current increases. In this work we study the entrainment mech- anism taking place between the ambient fluid layer and the turbidity current by means of fully resolved direct numerical simulations. Entrainment is a function of both the local Richardson number, Ri, and the non-dimensional settling velocity of the sediments. Here we consider a model turbidity current that is homogeneous in the streamwise direction. Thus, the effect of entrainment of clear fluid at the top of the turbidity current results in a temporal growth of the current height. With the assumption of streamwise homogeneity we investigate a non-stationary problem where the temporal growth of the height of the turbidity current is monitored in order to evaluate the role of entrainment of clear fluid.Publicado en: Mecánica Computacional vol. XXXV, no. 19Facultad de Ingenierí