42 research outputs found
SAGA: SystemC acceleration on GPU architectures
No full textSystemC is a widespread language for HW/SW system simulation and design exploration, and thus a key development platform in embedded system design. However, the growing complexity of SoC designs is having an impact on simulation performance, leading to limited SoC exploration potential, which in turns affects development and verification schedules and time-to-market for new designs. Previous efforts have attempted to parallelize SystemC simulation, targeting both multiprocessors and GPUs. However, for practical designs, those approaches fall far short of satisfactory performance. This paper proposes SAGA, a novel simulation approach that fully exploits the intrinsic parallelism of RTL SystemC descriptions, targeting GPU platforms. By limiting synchronization events with ad-hoc static scheduling and separate independent dataflows, we shows that we can simulate complex SystemC descriptions up to 16 times faster than traditional simulator
Possible knowledge: forms of literary and scientific thought in early modern England
No full textThis dissertation argues that the emergence of a new intellectual paradigm I call “possible knowledge”—encompassing projective, probable, counterfactual, hypothetical, conjectural, and prophetic ways of thinking—shaped literary and scientific writing in Renaissance England. The project uncovers a prehistory of scientific probability, still perceived as an Enlightenment-era phenomenon, by focusing on a constellation of speculative modes of knowing that drew on the imagination in the face of epistemic uncertainty. Possible knowledge emerges from elements crucial to our understanding of the literary, including mimesis, utopian discourse, and dramatic enactment, and it crosses generic boundaries. The disruption of prophetic certainty, for instance, informs the action in William Shakespeare’s _Macbeth_, while the unrepeatable epic events in John Milton’s _Paradise Lost_ reveal why contemporary experimental methods—which could produce only probable knowledge about the natural world—were insufficient to explicate prelapsarian states of being. I engage with the history and philosophy of science to show how the techniques of writing associated with possible knowledge are visible across modern disciplinary divides: the error and the endlessness that govern Edmund Spenser’s epic-romance, _The Faerie Queene_, are at the heart of the modern scientific epistemology laid out in Francis Bacon’s inductive method. And as Margaret Cavendish’s utopian experiment with cognitive realms in _The Blazing World_ underscores, possibility could allow authors intellectual freedom and creativity in their engagement with the material world. By focusing on hypothetical and suppositional modes of thinking, I map the contours of the humanities and the sciences as these began to assume their modern disciplinary forms.Ph. D.Includes bibliographical referencesby Debapriya Sarka
Novel custom designed toric piggyback intraocular lens for the correction of residual postoperative astigmatism
No full textWe report the outcomes of a custom-designed toric piggyback intraocular lens in a patient with high postoperative residual astigmatism. A 60-year-old male patient underwent customized toric piggyback IOL for postoperative residual astigmatism of 13 D, with follow-up examinations for IOL stability and refractive outcomes. The refractive error stabilized at two months and remained stable at one year, with a correction of nearly 9 D of astigmatism. The IOP remained within normal limits, and there were no postoperative complications. The IOL remained stable in the horizontal position. To our knowledge, this is the first case report of correction of unusually high astigmatism by a novel smart toric design of piggyback IOL
Statistical mechanical theory of equilibrium structure and miscibility of polymer nanocomposites: effects of polymer chemical heterogeneity and architecture, and nanoparticle surface corrugation and softness
No full textMotivated by the persistent interest in different nanoparticles added to various polymer matrices, the Polymer Reference Interaction Site Model (PRISM) theory is extended and applied to study the thermodynamics, statistical structure, and miscibility of diverse polymer nanocomposites (PNCs). Under chemistry-matched conditions and in the absence of interfacial attractions between a spherically smooth nanoparticle and the matrix fluid, the polymer-induced depletion attraction is dominant and induces entropic phase separation. The depletion attraction can be potentially reduced by modifying the nanoparticle surface topography as recently observed in experiments. Two types of surface-modified nanoparticles have been considered in this thesis – (1) spheres with ordered roughness on the surface and (2) soft polymeric nanoparticles with surface fluctuations and fuzziness. Monte Carlo integration and other computational techniques have been developed to compute the effective interactions between such particles. The morphologically diverse particles introduce additional length scales, making the physics non-monotonic, subtle, and rich. The common advantage with using either of the particles is reduced contact aggregation and enhanced miscibility. Optimal surface corrugation and/or particle softness allow monomer penetration resulting in favourable (entropic) mixing. However, high enough degree of corrugation/softness can also result in destabilization by excluding the polymer from its interior.
Another route of developing new nanocomposites is by tuning the polymer-particle interfacial chemistry. Prior work has established three states of spatial organization, namely depletion, steric stabilization and bridging, depending upon the effective interfacial attraction strengths. Introducing polymer chemical heterogeneity via the use of AB copolymers offers additional control over the equilibrium structure. Specifically, two types of copolymers are considered – (1) random copolymers (RCP) of disordered sequence and (2) ordered, alternating multiblock copolymers (MBCP). Quantum chemical calculations are combined with the polymer liquid state theory to predict structure and miscibility. The chain connectivity, monomer sequence, copolymer composition and differential wettability results in unique frustration in the system leading to novel states of organization of the polymer around the nanoparticles. In the context of strongly attractive nanoscopic fullerenes, this results in improved miscibility relative to the corresponding homopolymers. For some of the systems studied, maximum dispersion is predicted at an intermediate copolymer composition due to packing correlations and differential wetting effects with favourable comparison to experiments.Submission published under a 24 month embargo labeled 'U of I Access', the embargo will last until 2017-12-01The student, Debapriya Banerjee, accepted the attached license on 2015-07-29 at 10:23.The student, Debapriya Banerjee, submitted this Dissertation for approval on 2015-07-29 at 10:24.This Dissertation was approved for publication on 2015-07-31 at 15:42.DSpace SAF Submission Ingestion Package generated from Vireo submission #8651 on 2016-03-08 at 11:04:52Made available in DSpace on 2016-03-08T17:21:18Z (GMT). No. of bitstreams: 2
BANERJEE-DISSERTATION-2015.pdf: 12084334 bytes, checksum: 2e5ace4141f110955bfbb7a00b222bb8 (MD5)
LICENSE.txt: 4215 bytes, checksum: 32c70542a37bb0dee64ad93fa9116069 (MD5)
Previous issue date: 2015-07-31Embargo set by: Seth Robbins for item 91477
Lift date: 2018-03-08T17:22:13Z
Reason: Author requested U of Illinois access only (OA after 2yrs) in Vireo ETD systemU of I Only Restriction Lifted for Item 91477 on 2018-03-09T10:15:29Z
Harnessing Simulation Acceleration to Solve the Digital Design Verification Challenge.
No full textToday, design verification is by far the most resource and time-consuming activity of any new digital integrated circuit development. Within this area, the vast majority of the verification effort in industry relies on simulation platforms, which are implemented either in hardware or software. A "simulator" includes a model of each component of a design and has the capability of simulating its behavior under any input scenario provided by an engineer. Thus, simulators are deployed to evaluate the behavior of a design under as many input scenarios as possible and to identify and debug all incorrect functionality. Two features are critical in simulators for the validation effort to be effective: performance and checking/debugging capabilities. A wide range of simulator platforms are available today: on one end of the spectrum there are software-based simulators, providing a very rich software infrastructure for checking and debugging the design's functionality, but executing only at 1-10 simulation cycles per second (while actual chips operate at GHz speeds). At the other end of the spectrum, there are hardware-based platforms, such as accelerators, emulators and even prototype silicon chips, providing higher performances by 4 to 9 orders of magnitude, at the cost of very limited or non-existent checking/debugging capabilities. As a result, today, simulation-based validation is crippled: one can either have satisfactory performance on hardware-accelerated platforms or critical infrastructures for checking/debugging on software simulators, but not both.
This dissertation brings together these two ends of the spectrum by presenting solutions that offer high-performance simulation with effective checking and debugging capabilities. Specifically, it addresses the performance challenge of software simulators by leveraging inexpensive off-the-shelf graphics processors as massively parallel execution substrates, and then exposing the parallelism inherent in the design model to that architecture. For hardware-based platforms, the dissertation provides solutions that offer enhanced checking and debugging capabilities by abstracting the relevant data to be logged during simulation so to minimize the cost of collection, transfer and processing. Altogether, the contribution of this dissertation has the potential to solve the challenge of digital design verification by enabling effective high-performance simulation-based validation.PhDComputer Science and EngineeringUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttp://deepblue.lib.umich.edu/bitstream/2027.42/99781/1/dchatt_1.pd
Unilateral situs inversus of optic disc associated with reduced binocularity and stereoacuity resembling monofixation syndrome
No full textSitus inversus of the optic disc is a rare, usually bilateral, congenital embryological abnormality associated with high myopia, optic disc coloboma or tilted optic disc. It is characterized by emergence of the retinal vessels in an anomalous direction with dysversion of the optic disc. In this report we present a 13-year-old boy diagnosed with isolated, unilateral situs inversus of the optic disc associated with reduced binocularity and stereoacuity resembling a monofixation syndrome. The clinicians should be aware of this association and assess the binocularity in patients with unilateral optic disc or macular anomalies. Conversely, patients with reduced binocularity and stereoacuity should be carefully evaluated for macular or optic nerve anomalies, if not associated with strabismus, anisometropia and eccentric fixation. Typical fundus picture, optical coherence tomography and multifocal electro retinogram of the patient would be instructive to a clinician
