Work Stealing Scheduler for Automatic Parallelization in Faust

International audienceFaust 0.9.10 introduces an alternative to OpenMP based parallel code generation using a Work Steal- ing Scheduler and explicit management of worker threads. This paper explains the new option and presents some benchmarks

Temporal semantics for a live coding language

Sonic Pi is a music live coding language that has been designed for educational use as a first programming language. However, it is not straightforward to achieve the necessary simplicity of a first language in a music live coding setting, for reasons largely related to the manipulation of time. The original version of Sonic Pi used a `sleep' function for managing time, blocking computation for a specified time period. However, while this approach was conceptually simple, it resulted in badly timed music, especially when multiple musical threads were executing concurrently. This paper describes an alternative programming approach for timing (implemented in Sonic Pi v2.0) which maintains syntactic compatibility with v1.0, yet provides accurate timing via interaction between real time and a "virtual time''. We provide a formal specification of the temporal behaviour of Sonic Pi, motivated in relation to other recent approaches to the semantics of time in live coding and general computation. We then define a monadic model of the Sonic Pi temporal semantics which is sound with respect to this specification, using Haskell as a metalanguage

Excellentia Eminentia Effectio

"In these pages you will learn about the fascinating research endeavors that each of our faculty members is undertaking. We have divided their research into the broad categories of health, sustainability, information, and systems. While we recognize the imperfect nature of categorizing research that, by its very nature may be interdisciplinary or transdisciplinary, we nonetheless believe it will be helpful as a way to see the depth and breadth of our research endeavors within each grouping. As you read the profiles on these pages, I know you will begin to appreciate that, taken as a whole, the research spectrum at Columbia Engineering is exceptional and that, as our professors go about their work, they are at the cusp of making breakthroughs that will have a major impact on the way we live our lives today and tomorrow.

A Mixed-Method Study of One-To-One Mobile Technology Implementation in Math in a Rural Middle School

The purpose of this mixed-methods study was to examine the extent of one-to-one mobile technology implementation on student math achievement as measured by standardized test scores. A second focus was on the extent one-to-one mobile technology implementation has influenced teacher practices in math instruction. A final focus was on the extent that teacher lesson plans support or fail to support technology implementation. The setting for the study was a small rural middle school in the Upstate of South Carolina. The participants consisted of males and females from several ethnicities and socioeconomic classes. A parallel/simultaneous method was used for the study. The results revealed statistically significant differences in student achievement growth between grade levels. The areas of gender, ethnicity, and socioeconomic status did not result in any statistically significant differences. Teacher perceptions of technology and implementation varied. The teachers with greater technology proficiency had lower student growth. Teacher lesson plans included technology implementation to a great extent

Sculptured computational objects with smart and active computing materials

Thesis (Ph. D.)--Massachusetts Institute of Technology, School of Architecture and Planning, Program in Media Arts and Sciences, 2001.Includes bibliographical references (leaves 325-328).This thesis presents the creative, technological, and philosophical means and methodology, by which technology artists and researchers can materially and sculpturally transform physical computing technology from hard, remotely-designed, plastic shells, into intimately created, sensual computing objects and artifacts. It asserts that the rigid, square, and prefabricated physical materials of computing technology are a fundamental technological and artistic limitation to anyone who wishes to sensually transform physical computing technology, or develop a rich artistic vocabulary for it. Smart and active sculptural computing materials are presented as a solution to this problem. Practically, smart computing materials reduce the number of separate, rigid, and square prefabricated parts required to create physical computing objects. Artistically, active sculptural computing materials give artists and designers the ability to directly manipulate, shape, experiment with, and therefore aesthetically understand the real, physical materials of computing technology. Such active design materials will also enable creative people to develop a meaningful artistic relationship between physical form and computation. The total contributions of this thesis include a proposal for a future three-dimensional design/technology practice, a portfolio of sensually transformed expressive computational objects (including new physical interfaces, electronic fashions, and embroidered musical instruments), and the smart and active sculptural computing materials and processes (in this case smart textiles), which make that transformation possible. Projects from the design portfolio include: The Triangles, and its applications; Electronic Fashions, including the Firefly Dress and Necklace, New Year's Eve Ball Gown, and Serial Suit; The Musical Jacket; Electronic Tablecloths; and a series of Embroidered Musical Instruments with embroidered pressure sensors. Contributions from the supporting technical area include: the first fabric keypad (a row and column switch matrix), a new conductive yarn capable of tying and electrical/mechanical knot, an advanced process for machine embroidering highly conductive, flexible and visually diverse electrodes, an empirical model of complex impedance sensing, and a definition of and test for the machine sewability and flexibility of yarns. These contributions are presented in three sections: 1) the supporting arguments, and philosophy of materiality and computation behind this work, 2) the design portfolio, and 3) the supporting technical story.by Margaret A. Orth.Ph.D

SCALABLE INTEGRATED CIRCUIT SIMULATION ALGORITHMS FOR ENERGY-EFFICIENT TERAFLOP HETEROGENEOUS PARALLEL COMPUTING PLATFORMS

Integrated circuit technology has gone through several decades of aggressive scaling.It is increasingly challenging to analyze growing design complexity. Post-layout SPICE simulation can be computationally prohibitive due to the huge amount of parasitic elements, which can easily boost the computation and memory cost. As the decrease in device size, the circuits become more vulnerable to process variations. Designers need to statistically simulate the probability that a circuit does not meet the performance metric, which requires millions times of simulations to capture rare failure events. Recent, multiprocessors with heterogeneous architecture have emerged as mainstream computing platforms. The heterogeneous computing platform can achieve highthroughput energy efficient computing. However, the application of such platform is not trivial and needs to reinvent existing algorithms to fully utilize the computing resources. This dissertation presents several new algorithms to address those aforementioned two significant and challenging issues on the heterogeneous platform. Harmonic Balance (HB) analysis is essential for efficient verification of large postlayout RF and microwave integrated circuits (ICs). However, existing methods either suffer from excessively long simulation time and prohibitively large memory consumption or exhibit poor stability. This dissertation introduces a novel transient-simulation guided graph sparsification technique, as well as an efficient runtime performance modeling approach tailored for heterogeneous manycore CPU-GPU computing system to build nearly-optimal subgraph preconditioners that can lead to minimum HB simulation runtime. Additionally, we propose a novel heterogeneous parallel sparse block matrix algorithm by taking advantages of the structure of HB Jacobian matrices as well as GPU’s streaming multiprocessors to achieve optimal workload balancing during the preconditioning phase of HB analysis. We also show how the proposed preconditioned iterative algorithm can efficiently adapt to heterogeneous computing systems with different CPU and GPU computing capabilities. Extensive experimental results show that our HB solver can achieve up to 20X speedups and 5X memory reduction when compared with the state-of-the-art direct solver highly optimized for twelve-core CPUs. In nowadays variation-aware IC designs, cell characterizations and SRAM memory yield analysis require many thousands or even millions of repeated SPICE simulations for relatively small nonlinear circuits. In this dissertation, for the first time, we present a massively parallel SPICE simulator on GPU, TinySPICE, for efficiently analyzing small nonlinear circuits. TinySPICE integrates a highly-optimized shared-memory based matrix solver and fast parametric three-dimensional (3D) LUTs based device evaluation method. A novel circuit clustering method is also proposed to improve the stability and efficiency of the matrix solver. Compared with CPU-based SPICE simulator, TinySPICE achieves up to 264X speedups for parametric SRAM yield analysis without loss of accuracy

Content rendering and interaction technologies for digital heritage systems

Existing digital heritage systems accommodate a huge amount of digital repository information; however their content rendering and interaction components generally lack the more interesting functionality that allows better interaction with heritage contents. Many digital heritage libraries are simply collections of 2D images with associated metadata and textual content, i.e. little more than museum catalogues presented online. However, over the last few years, largely as a result of EU framework projects, some 3D representation of digital heritage objects are beginning to appear in a digital library context. In the cultural heritage domain, where researchers and museum visitors like to observe cultural objects as closely as possible and to feel their existence and use in the past, giving the user only 2D images along with textual descriptions significantly limits interaction and hence understanding of their heritage. The availability of powerful content rendering technologies, such as 3D authoring tools to create 3D objects and heritage scenes, grid tools for rendering complex 3D scenes, gaming engines to display 3D interactively, and recent advances in motion capture technologies for embodied immersion, allow the development of unique solutions for enhancing user experience and interaction with digital heritage resources and objects giving a higher level of understanding and greater benefit to the community. This thesis describes DISPLAYS (Digital Library Services for Playing with Shared Heritage Resources), which is a novel conceptual framework where five unique services are proposed for digital content: creation, archival, exposition, presentation and interaction services. These services or tools are designed to allow the heritage community to create, interpret, use and explore digital heritage resources organised as an online exhibition (or virtual museum). This thesis presents innovative solutions for two of these services or tools: content creation where a cost effective render grid is proposed; and an interaction service, where a heritage scenario is presented online using a real-time motion capture and digital puppeteer solution for the user to explore through embodied immersive interaction their digital heritage