1,721,067 research outputs found
Parallel Algorithm Scalability Issues in PetaFLOPS Architectures
No full textThe projected design space of petaFLOPS architectures entails exploitationof very large degrees of concurrency, locality of data access, and toleranceto latency. This puts considerable pressure on the design of parallelalgorithms capable of effectively utilizing increasing amounts of processingresources in a memory and bandwidth constrained environment. This aspect ofalgorithm design, also referred to as scalability analysis, is a keycomponent for guiding algorithm designers as well as hardware architects.By identifying bottlenecks to scalability and machine parameters thatinfluence these bottlenecks, scalability analysis provides insights toalleviating the bottlenecks in the context of the specific algorithm.In this paper, we motivate the need for, and benefits of scalabilityanalysis in the context of petaFLOPS systems. We overview variousscalability metrics and study their suitability to petaFLOPS system.We also present sample analysis of selected computational kernels fromdense linear algebra, fast fourier transforms, and data intensive applications(association rule mining). The objective of this analysis is to demonstratethe analysis framework and its use in identifying desirable architecturalfeatures as well the ability of these selected kernels to scale to petaFLOPSsystems.Garma, Ananth; Gupta, Anshul; Han, Euihong; Kumar, Vipin. (2001). Parallel Algorithm Scalability Issues in PetaFLOPS Architectures. Retrieved from the University Digital Conservancy, https://hdl.handle.net/11299/215488
Characterization and modeling of hot carrier degradation in N-channel gate-all-around nanowire FETs
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Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe 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
Get PDF“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
Get PDFWe 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
Application of HPC for power system operation and electricity market tools for power networks of the future
No full textDevelopment and application of SmartGrids or Intelligrids, including roll-out of smart meters and electrical vehicles, is of a great importance if the UK and other countries are to achieve significant carbon emission reductions and realize sustainable energy systems. These new grids will offer the opportunity to increase the level of renewable energy integrated into the system. They will also allow customers, including small households, to actively participate and adjust their demand depending on energy availability and price. This will further lead towards improved energy efficiency, as well as offer possibilities to reduce overall consumption and reduce or postpone investments into new large generation and infrastructure facilities. To achieve these goals, a number of technical, economical and policy issues need to be addressed and resolved. The development of new generations of extremely fast software tools that can solve power system problems with large number of nodes will also be important to help resolve these issues. For example, distribution system and network operators, as well as trading entities such as aggregators, will get a better coordination of system operation though the possibility to engage with even smaller generators, and especially smaller customers. This control at lower voltage levels will allow for the aggregation of responses which will then propagate to higher voltage levels. Currently, the discussion regarding the operation of future power systems is looking into two different options. One is to develop methodologies that will allow decentralization of network operation with the reduced level of coordination at the high level of system operation. However, the new software developed to exploit the benefits of the HPC architecture may open a possibility for businesses and policy makers to investigate and compare operation of centralized vs. decentralized operation over areas with large number of participants.. These new HPC power system analysis tools will enable more frequent price signal calculations and bring the possibility to define policies which will ensure engagement with customers to reduce their energy consumption or shift it towards offpeak periods, as well as allow for the coordination of charging of electric vehicles and their use as storage devices. Such tools will be useful for both decentralized and centralized operation, however they will be crucial for the latter. This chapter will first give an overview of the changes in future power system operation and then outline power system analysis tools such as power flow, optimal power flow, generation scheduling and the security assessment. It will then discuss current status of the parallel techniques and HPC applications for the power system operation tools. It will also discuss the formulation requirements, achievements and possible obstacles in the application of techniques suitable for HPC and for power system operation problems such as power flow, optimal power flow (OPF), security constrained OPF. Finally, it will look how new developments in the HPC/Numerical Analysis area, and even more powerful Extreme Computing together with new algorithms developed for this next-step class of machines may help improve power system operation and electricity markets tools
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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