1,721,348 research outputs found
A Data-Flow Soft-Core Processor for Accelerating Scientific Calculation on FPGAs
Full text linkWe present a new type of soft-core processor called the “Data-Flow Soft-Core” that can be implemented through FPGA technology with adequate interconnect resources. This processor provides data processing based on data-flow instructions rather than control flow instructions. As a result, during an execution on the accelerator of the Data-Flow Soft-Core, both partial data and instructions are eliminated as traffic for load and store activities. Data-flow instructions serve to describe a program and to dynamically change the context of a data-flow program graph inside the accelerator, on-the-fly. Our proposed design aims at combining the performance of a fine-grained data-flow architecture with the flexibility of reconfiguration, without requiring a partial reconfiguration or new bit-stream for reprogramming it. The potential of the data-flow implementation of a function or functional program can be exploited simply by relying on its description through the data-flow instructions that reprogram the Data-Flow Soft-Core. Moreover, the data streaming process will mirror those present in other FPGA applications. Finally, we show the advantages of this approach by presenting two test cases and providing the quantitative and numerical results of our evaluations
Teleology and World from Different Perspectives: Philosophy of Mind and Transcendental Phenomenology. Introduction
No full textThis is not really an article but only an introduction to an issue devoted to consider the possibility of rehabilitating a teleological explanation of the world from the points of view of the anti-reductionist philosophy of mind and from that of transcendental phenomenology
A scalable thread scheduling co-processor based on data-flow principles
No full textLarge synchronization and communication overhead will become a major concern in future extreme-scale machines (e.g., HPC systems, supercomputers). These systems will push upwards performance limits by adopting chips equipped with one order of magnitude more cores than today. Alternative execution models can be explored in order to exploit the high parallelism offered by future massive many-core chips. This paper proposes the integration of standard cores with dedicated co-processing units that enable the system to support a fine-grain data-flow execution model developed within the TERAFLUX project. An instruction set architecture extension for supporting fine-grain thread scheduling and execution is proposed. This instruction set extension is supported by the co-processor that provides hardware units for accelerating thread scheduling and distribution among the available cores. Two fundamental aspects are at the base of the proposed system: the programmers can adopt their preferred programming model, and the compilation tools can produce a large set of threads mainly communicating in a producer-consumer fashion, hence enabling data-flow execution. Experimental results demonstrate the feasibility of the proposed approach and its capability of scaling with the increasing number of cores
WebRISC-V: A 32/64-bit RISC-V pipeline simulation tool
Full text linkWebRISC-V is a web-based education-oriented tool, which permits the investigation of the pipelined execution of assembly programs according to the RV32IM and RV64IM specifications (32-bit or 64-bit RISC-V processor). The tool permits to evaluate and understand slow-downs in the execution due to pipeline stalls and further investigate the internal state of the pipeline architectural blocks (e.g., registers, memory, multiplexers, ALU). The pipeline concept is illustrated in the vast majority of university courses in Computer Architecture, since it is the well established standard for implementing high-performance processors. However, the impact of pipelined execution is often underestimated or even unknown, whilst it represents a very important source for the speed-up of programs. Several similar tools exist and are publicly available, but WebRISC-V is currently the first one that can be executed directly in a web-browser while displaying the cycle-by-cycle detailed pipeline execution for a RISC-V processor. This paper describes WebRISC-V, compares it against other similar available tools and presents its features. An example of usage for investigating the pipeline with the support of an automatically generated pipeline diagram is provided
Exploring future many-core architectures: the TERAFLUX evaluation framework
No full textAbstract The design of new computer systems always requires a strong simulation effort in order to evaluate different design options. This is especially true if the system is to be produced at a date far in the future, such as in the case of TERAFLUX, a system aimed at containing something like 1012 (1 TERA) transistors in a single package or a (multilayer) chip by 2020. At the basis of a \TERAFLUX\ system, a dataflow execution model supports the execution of threads. In order to explore the design space, \TERAFLUX\ provides an appropriate evaluation framework, at the scale of at least 1000 general purpose cores on a single chip. Predicting the performance of such a next-generation platform is not a trivial task. Today, no software-based tool exists that can provide cycle-level full-system simulation and faithfully predict the behavior of 1000 general-purpose cores, in an acceptable amount of time and with reasonable accuracy, while providing the flexibility of changing the execution model at the architectural level. A solid evaluation framework represents an important base for exploring future many cores. In this chapter, different options for simulating a 1000 general-purpose-core system are explored. Finally, we show the setup that successfully allowed us to evaluate our 1000 core target while running a full-system Linux operating system
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
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