806 research outputs found

    Integrating communication protocol selection with partitioning in hardware/software codesign

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    This paper presents a codesign approach which incorpo-rates communication protocol selection as a design param-eter within hardware/software partitioning. The presented approach takes into account data transfer rates depending on communication protocol types and configurations, and different operating frequencies of system components, i.e. CPUs, ASICs, and busses. It also takes into account the tim-ing and area influences of drivers and driver calls needed to perform the communication. The approach is illustrated by a number of design space exploration experiments which use models of the PCI and USB communication protocols. 1

    PACE: A dynamic programming algorithm for hardware/software partitioning

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    . This paper presents the PACE partitioning algorithm which is used in the LYCOS co-synthesis system for partitioning control/dataflow graphs into hardwareand software parts. The algorithm is a dynamic programming algorithm which solves both the problem of minimizing system execution time with a hardware area constraint and the problem of minimizing hardware area with a system execution time constraint. The target architecture consists of a single microprocessor and a single hardware chip (ASIC, FPGA, etc.) which are connected by a communication channel. The algorithm incorporates a realistic communication model and thus attempts to minimize communication overhead. The time-complexity of the algorithm is O(n 2 \Delta A) and the space-complexity is O(n \Delta A) where A is the total area of the hardware chip and n the number of code fragments which may be placed in either hardware or software. 1 Introduction The hardware/software partitioning of a system specification onto a target..

    Aspects of system modelling in Hardware/Software partitioning

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    This paper addresses fundamental aspects of system modelling and partitioning algorithms in the area of Hardware/Software Codesign. Three basic system models for partitioning are presented and the consequences of partitioning according to each of these are analyzed. The analysis shows the importance of making a clear distinction between the model used for partitioning and the model used for evaluation. It also illustrates the importance of having a realistic hardware model such that hardware sharing can be taken into account. Finally, the importance of integrating scheduling and allocation with partitioning is demonstrated. 1 Introduction Hardware/software partitioning is often viewed as the synthesis of an architecture consisting of a single CPU and a single dedicated hardware component (full custom, FPGA, etc.) from an initial system specification, e.g., [1]. The aim of this paper is to emphasize the importance of clearly defining and reporting the partitioning model assumed by a pa..

    Communication Estimation for Hardware/Software Codesign

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    This paper presents a general high level estimation model of communication throughput for the implementation of a given communication protocol. The model, which is part of a larger model that includes component price, software driver object code size and hardware driver area, is intended to be general enough to be able to capture the characteristics of a wide range of communication protocols and yet to be sufficiently detailed as to allow the designer or design tool to efficiently explore tradeoffs between throughput, bus widths, burst/non-burst transfers and data packing strategies. Thus it provides a basis for decision making with respect to communication protocols/components and communication driver design in the initial design space exploration phase of a co-synthesis process where a large number of possibilities must be examined and where fast estimators are therefore necessary. The full model allows for additional (money)cost, software code size and hardware area tradeoffs to be ..

    Graph based communication analysis for hardware/software codesign

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    In this paper we present a coarse grain CDFG (Control/Data Flow Graph) model suitable for hardware/software partitioning of single processes and demonstrate how it is necessary to perform various transformations on the graph structure before partitioning in order to achieve a structure that allows for accurate estimation of communication overhead between nodes mapped to different processors. In particular, we demonstrate how various transformations of control structures can lead to a more accurate communication analysis and more efficient implementations. The purpose of the transformations is to obtain a CDFG structure that is sufficiently fine grained as to support a correct communication analysis but not more fine grained than necessary as this will increase partitioning and analysis time. 1 Introduction In this paper we focus on communication analysis for hardware /software partitioning of control-intensive applications that are specified using hierarchy, functions, conditionals ..

    Foreword

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    Early Middle Cambrian bituminous coquinoid limestones from a tectonically isolated outcrop in southwestern Kyrgyzstan yield a remarkably diverse fauna, with stem-group cnidarians, trilobites, rhynchonelliformean brachiopods, and other shelly fossils. The fossil site is in the northern foothills of the Turkestan Range and thus forms part of the westernmost extension of the South Tien Shan. The fauna includes two fairly well known trilobite species, Glabrella ventrosa Lermontova, 1940 and Dorypyge richthofeniformis Lermontova, 1940, that provide confident support for an Amgan age of the rocks. New described taxa include the stem-group cnidarian Cambroctoconus kyrgyzstanicus Peel sp. nov., the trilobite Olenoides sagittatus Geyer sp. nov., and the helcionelloid Manasoconus bifrons Peel gen. et sp. nov. Additional fossils within the samples include the trilobites Olenoides sp. A, Kootenia sp., and Pseudoeteraspis? sp.; the rhynchonelliform brachiopods Narynella cf. ferganensis (Andreeva, 1962), Narynella? sp., Austrohedra? sp. nov., and two species of uncertain generic affinity; the tommotiid Tesella sp.; the hyolithelminth Hyolithellus sp.; and the palaeoscolecid Hadimopanella oezgueli Gedik, 1977. Of particular interest is Cambroctoconus kyrgyzstanicus with an octagonal corallum and a sparsely septate calyx

    Resonance fluorescence of a site-controlled quantum dot realized by the buried-stressor growth technique

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    This article may be downloaded for personal use only. Any other use requires prior permission of the author and AIP Publishing. This article appeared in Appl. Phys. Lett. 110, 111101 (2017) and may be found at https://doi.org/10.1063/1.4978428.Site-controlled growth of semiconductor quantum dots (QDs) represents a major advancement to achieve scalable quantum technology platforms. One immediate benefit is the deterministic integration of quantum emitters into optical microcavities. However, site-controlled growth of QDs is usually achieved at the cost of reduced optical quality. Here, we show that the buried-stressor growth technique enables the realization of high-quality site-controlled QDs with attractive optical and quantum optical properties. This is evidenced by performing excitation power dependent resonance fluorescence experiments at cryogenic temperatures showing QD emission linewidths down to 10 ΌeV. Resonant excitation leads to the observation of the Mollow triplet under CW excitation and enables coherent state preparation under pulsed excitation. Under resonant π-pulse excitation we observe clean single-photon emission associated with g(2)(0) = 0.12 limited by non-ideal laser suppression.EC/FP7/615613/EU/External Quantum Control of Photonic Semiconductor Nanostructures/EXQUISIT

    Hardware Resource Allocation for Hardware/Software Partitioning in the LYCOS System

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    This paper presents a novel hardware resource alloca-tion technique for hardware/software partitioning. It al-locates hardware resources to the hardware data-path us-ing information such as data-dependencies between op-erations in the application, and profiling information. The algorithm is useful as a designer’s/designtool’s aid to generate good hardware allocations for use in hard-ware/software partitioning. The algorithm has been imple-mented in a tool under the LYCOS system [9]. The results show that the allocations produced by the algorithm come close to the best allocations obtained by exhaustive search.

    Sexual Dimorphism in the Attachment Ability of Leptinotarsa decemlineata Say (Coleoptera, Chrysomelidae) on Rough Substrata

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    Leptinotarsa decemlineata lebt oligophag ausschließlich auf Vertretern der Solanaceae, insbesondere Solanum spp. (Radcliffe 1982). Die herbivore Spezies ist fĂ€hig, erfolgreich auf den unbehaarten, behaarten und glandulĂ€r behaarten BlattoberflĂ€chen der NachtschattengewĂ€chse zu haften, sich fortzubewegen und zu leben. Dazu verhelfen paarige Krallen und Hafthaarkissen an den Tarsen (Rivnay 1928). Das ausgesprochen gute Haftvermögen und die SubstratanpassungsfĂ€higkeit haariger Haftsysteme von Insekten sind fĂŒr verschiedene Vertreter der Diptera und Coleoptera experimentell belegt (siehe Review von Gorb 2001). Stork (1980 a, b) beobachtete insbesondere bei KĂ€fern der Familien Chrysomelidae und Coccinellidae einen ausgeprĂ€gten Sexualdimorphismus der tarsalen Hafthaare. Schanz (1953) beschreibt fĂŒr L. decemlineata drei verschiedene Hafthaartypen: (1) Haare mit sich asymmetrisch verjĂŒngenden Spitzen, (2) spatelförmige Gebilde und (3) Haare mit Haftsohlen, welche nur die MĂ€nnchen besitzen. Hinsichtlich der geschlechterspezifischen Unterschiede der Haftkraft auf verschieden rauen OberflĂ€chen existieren bislang wenige quantitative Nachweise. Pelletier & Smilowitz (1987) wiesen fĂŒr MĂ€nnchen von L. decemlineata in Inversionsexperimenten ein außerordentliches Haftvermögen auf Glas- und KunststoffoberflĂ€chen nach, wobei sie dessen GrĂŒnde in den maskulin-spezifischen Hafthaaren mit scheibenförmig verbreiterten Enden vermuteten. Die FĂ€higkeit der MĂ€nnchen, an glatten OberflĂ€chen besonders gut zu haften, wurde als eine Anpassung an die Haftung auf den glatten OberflĂ€chen der Weibchenelytren wĂ€hrend der Kopulation erklĂ€rt. Die meisten natĂŒrlichen OberflĂ€chen (insbesondere PflanzenoberflĂ€chen) sind jedoch rau. Somit besteht die Frage, ob beide Geschlechter auch eine unterschiedliche Spezialisierung der Haftsysteme fĂŒr die Haftung auf rauen Substraten besitzen. Um den Einfluss unterschiedlicher OberflĂ€chenrauhigkeiten auf die HaftsystemfunktionalitĂ€t der Weibchen und MĂ€nnchen von L. decemlineata zu prĂŒfen, wurden in der vorliegenden Studie Kraftmessungen mit einzelnen Individuen auf OberflĂ€chen mit exakt definierter Rauheit durchgefĂŒhrt.The remarkable attachment ability and the adaptability to different substrates of insects‘ hairy attachment systems have been experimentally demonstrated in representatives of Diptera and Coleoptera. Many representatives from the family Chrysomelidae exhibit a distinctive sexual dimorphism in the structure of adhesive tarsal hairs. Differences in attachment ability between sexes have been previously reported for smooth substrata. In L. decemlineata, a very strong attachment ability on smooth glass and plastic surfaces has been described in males, and explained by the action of specialised mushroom-like tarsal hairs. The present study demonstrates the influence of different surface roughnesses on the attachment forces of L. decemlineata males and females. The maximum attachment force of individual beetles was measured on epoxy resin surfaces (0-12 μm surface roughness) using a centrifugal force tester. On the smooth surface, no considerable differences between males and females were found, whereas, on rough surfaces, adherence of females was significantly stronger, up to twice that of males. The results indicate that the main functional trait of the adhesive system of females is its stronger specialization to rough plant surfaces
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