184 research outputs found

    Compiling Geometric Algebra Computations into Reconfigurable Hardware Accelerators

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    Geometric Algebra (GA), a generalization of quaternions and complex numbers, is a very powerful framework for intuitively expressing and manipulating the complex geometric relationships common to engineering problems. However, actual processing of GA expressions is very compute intensive, and acceleration is generally required for practical use. GPUs and FPGAs offer such acceleration, while requiring only low-power per operation. In this paper, we present key components of a proof-of-concept compile flow combining symbolic and hardware optimization techniques to automatically generate hardware accelerators from the abstract GA descriptions that are suitable for high-performance embedded computing

    Rapid Prototyping and Exploration Environment for Generating C-to-Hardware-Compilers

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    There is today an ever-increasing demand for more computational power coupled with a desire to minimize energy requirements. Hardware accelerators currently appear to be the best solution to this problem. While general purpose computation with GPUs seem to be very successful in this area, they perform adequately only in those cases where the data access patterns and utilized algorithms fit the underlying architecture. ASICs on the other hand can yield even better results in terms of performance and energy consumption, but are very inflexible, as they are manufactured with an application specific circuitry. Field Programmable Gate Arrays (FPGAs) represent a combination of approaches: With their application specific hardware they provide high computational power while requiring, for many applications, less energy than a CPU or a GPU. On the other hand they are far more flexible than an ASIC due to their reconfigurability. The only remaining problem is the programming of the FPGAs, as they are far more difficult to program compared to regular software. To allow common software developers, who have at best very limited knowledge in hardware design, to make use of these devices, tools were developed that take a regular high level language and generate hardware from it. Among such tools, C-to-HDL compilers are a particularly wide-spread approach. These compilers attempt to translate common C code into a hardware description language from which a datapath is generated. Most of these compilers have many restrictions for the input and differ in their underlying generated micro architecture, their scheduling method, their applied optimizations, their execution model and even their target hardware. Thus, a comparison of a certain aspect alone, like their implemented scheduling method or their generated micro architecture, is almost impossible, as they differ in so many other aspects. This work provides a survey of the existing C-to-HDL compilers and presents a new approach to evaluating and exploring different micro architectures for dynamic scheduling used by such compilers. From a mathematically formulated rule set the Triad compiler generates a backend for the Scale compiler framework, which then implements a hardware generation backend with described dynamic scheduling. While more than a factor of four slower than hardware from highly optimized compilers, this environment allows easy comparison and exploration of different rule sets and the micro architecture for the dynamically scheduled datapaths generated from them. For demonstration purposes a rule set modeling the COCOMA token flow model from the COMRADE 2.0 compiler was implemented. Multiple variants of it were explored: Savings of up to 11% of the required hardware resources were possible

    HTML Violations and Where to Find Them: A Longitudinal Analysis of Specification Violations in HTML

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    With the increased interest in the web in the 90s, everyone wanted to have their own website. However, given the lack of knowledge, such pages contained numerous HTML specification violations. This was when browser vendors came up with a new feature – error tolerance. This feature, part of browsers ever since, makes the HTML parsers tolerate and instead fix violations temporarily. On the downside, it risks security issues like Mutation XSS and Dangling Markup. In this paper, we asked ourselves, do we still need to rely on this error tolerance, or can we abandon this security issue? To answer this question, we study the evolution of HTML violations over the past eight years. To this end, we identify security-relevant violations and leverage Common Crawl to check archived pages for these. Using this framework, we automatically analyze over 23K popular domains over time. This analysis reveals that while the number of violations has decreased over the years, more than 68% of all domains still contain at least one HTML violation today. While this number is obviously too high for browser vendors to tighten the parsing process immediately, we show that automatic approaches could quickly correct up to 46% of today’s violations. Based on our findings, we propose a roadmap for how we could tighten this process to improve the quality of HTML markup in the long run

    You Call This Archaeology? Evaluating Web Archives for Reproducible Web Security Measurements

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    Given the dynamic nature of the Web, security measurements on it suffer from reproducibility issues. In this paper we take a systematic look into the potential of using web archives for web security measurements. We first evaluate an extensive set of web archives as potential sources of archival data, showing the superiority of the Internet Archive with respect to its competitors. We then assess the appropriateness of the Internet Archive for historical web security measurements, detecting subtleties and possible pitfalls in its adoption. Finally, we investigate the feasibility of using the Internet Archive to simulate live security measurements, using recent archival data in place of live data. Our analysis shows that archive-based security measurements are a promising alternative to traditional live security measurements, yet reproducible by design. As an important contribution, we identify insights and best practices for future archive-based security measurements

    New HARPS and FEROS observations of GJ1046

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    In this paper we present new precise Doppler data of GJ1046 taken between November 2005 and July 2018 with the HARPS and the FEROS high-resolution spectographs. In addition, we provide a new stellar mass estimate of GJ1046 and we update the orbital parameters of the GJ1046 system. These new data and analysis could be used together with the GAIA epoch astrometry, when available, for braking the sini\sin i degeneracy and revealing the true mass of the GJ1046 system.Comment: 2 pages, 1 figure, 1 table with RV data (available only in the Astro-PH version of the paper), Accepted by RNAA

    Implementing chemical functionality into oriented films of metal–organic frameworks on self-assembled monolayers

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    The generation of thin films of oriented functionalized metal–organic frameworks (MOFs) on self-assembled monolayers was achieved via direct growth from solution. Specifically, the direct growth from solvothermally pretreated synthesis solutions of two different MOF structures with amino functionality was investigated: the flexible framework structure NH2–Fe–MIL-88B and the mesoporous MOF NH2–Fe–MIL-101 with its remarkably large unit cell. Both MOF structures can be grown in a highly oriented fashion on self-assembled monolayers of 16-mercaptohexadecanoic acid on gold. With the help of a quartz crystal microbalance we demonstrate that the introduction of amino groups into the framework strongly affects the host–guest interactions towards ethanol molecules: thin films of NH2–Fe–MIL-88B show a significantly higher uptake of ethanol than unfunctionalized Fe–MIL-88B films. In situ XRD experiments during sorption of ethanol showed that the amino group does have an impact on the cell parameters of the structure, but the flexibility ("breathing") during ad- and desorption of ethanol is similar for the functionalized and the unfunctionalized structures. It is anticipated that the implementation of chemical functionalities into oriented MOF films will lead to selective host–guest interactions that are of key importance for chemical sensing and other applications

    Mistral 7B

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    We introduce Mistral 7B v0.1, a 7-billion-parameter language model engineered for superior performance and efficiency. Mistral 7B outperforms Llama 2 13B across all evaluated benchmarks, and Llama 1 34B in reasoning, mathematics, and code generation. Our model leverages grouped-query attention (GQA) for faster inference, coupled with sliding window attention (SWA) to effectively handle sequences of arbitrary length with a reduced inference cost. We also provide a model fine-tuned to follow instructions, Mistral 7B -- Instruct, that surpasses the Llama 2 13B -- Chat model both on human and automated benchmarks. Our models are released under the Apache 2.0 license.Comment: Models and code are available at https://mistral.ai/news/announcing-mistral-7b

    The QCD confinement transition: hadron formation

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    We review the foundations and the applications of the statistical and the quark recombination model as hadronization models.Comment: 45 pages, 16 figures, accepted for publication in Landolt-Boernstein Volume 1-23
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