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951.
Bart Pieters Charles-Frederik Hollemeersch Jan De Cock Peter Lambert Rik Van de Walle 《Signal Processing: Image Communication》2012,27(3):220-237
With the increasing number of processor cores available in modern computing architectures, task or data parallelism is required to maximally exploit the available hardware and achieve optimal processing speed. Current state-of-the-art data-parallel processing methods for decoding image and video bitstreams are limited in parallelism by dependencies introduced by the coding tools and the number of synchronization points introduced by these dependencies, only allowing task or coarse-grain data parallelism. In particular, entropy decoding and data prediction are bottleneck coding tools for parallel image and video decoding. We propose a new data-parallel processing scheme for block-based intra sample and coefficient prediction that allows fine-grain parallelism and is suitable for integration in current and future state-of-the-art image and video codecs. Our prediction scheme enables maximum concurrency, independent of slice or tile configuration, while minimizing synchronization points. This paper describes our data-parallel processing scheme for one- and two-dimensional prediction and investigates its application to block-based image and video codecs using JPEG XR and H.264/AVC Intra as a starting point. We show how our scheme enables faster decoding than the state-of-the-art wavefront method with speedup factors of up to 21.5 and 7.9 for JPEG XR and H.264/AVC Intra coding tools respectively. Using the H.264/AVC Intra coding tool, we discuss the requirements of the algorithm and the impact on decoded image quality when these requirements are not met. Finally, we discuss the impact on coding rate in order to allow for optimal parallel intra decoding. 相似文献
952.
Jerico Moeyersons Pieter‐Jan Maenhaut Filip Turck Bruno Volckaert 《International Journal of Network Management》2020,30(2)
Software‐defined networking (SDN) is a new network paradigm that is separating the data plane and the control plane of the network, making one or more centralized controllers to supervise the behaviour of the entire network. Different types of SDN controller software exist, and research dealing with the difficulties of consistently integrating these different controller types has mostly been declared future work. In this paper, the Domino framework is proposed, a pluggable SDN framework for managing heterogeneous SDN networks. In contrast to related work, the proposed framework allows research into SDN networks controlled by different types of SDN controllers attempting to standardize the northbound API of them. Domino implements a microservice plugin architecture where users can link different SDN networks to a processing algorithm. Such an algorithm allows for, eg, adapting the flows by building a pipeline using plugins that either invoke other SDN operations or generic data processing algorithms. The Domino framework is evaluated by implementing a proof‐of‐concept implementation, which is tested on the initial requirements. It achieves the modifiability and the interoperability with an average successful exchange ratio of 99.99%. The performance requirements are met for the frequently used commands with an average response time of 0.26 seconds, and the framework can handle at least 72 plugins simultaneously depending on the available amount of RAM. The proposed framework is evaluated by means of the implementation of a shortest path routing algorithm between heterogeneous SDN networks. 相似文献
953.
Jan Helsen Frederik VanhollebekeFilip De Coninck Dirk VandepitteWim Desmet 《Mechatronics》2011,21(4):737-752
Guaranteeing reliable and cost-effective wind turbine drive trains requires expert insights in dynamics during operation. A combination of advanced modeling techniques and detailed measurements are suggested to realize this goal. The flexible multibody modeling technique enables the simulation of dynamic loads on all drive train components. Moreover it facilitates estimation of structural component deformation caused by dynamic loading. This paper gives a detailed overview of the assumptions made in this modeling approach. Furthermore the influence of the different structural component flexibilities is investigated in detail. To gain confidence in the models created, model validation by means of a comparison with measurements is necessary. To overcome issues concerning test repeatability experienced in field testing, test-rig testing is suggested as a valid alternative. In order to be representative, dedicated dynamic load cases, which represent specific dynamic behavior of the gearbox in a wind turbine need to be realized on the test-rig. However a highly dynamic test-rig complying with the specifications was not commercially available. Therefore Hansen developed a high dynamic test-rig with a nominal power of 13.2 MW and a peak power capacity of 16.8 MW. A back-to-back gearbox configuration was used. The complexity of controlling dynamics of the test-rig was solved by identifying dedicated load cases which represent specific wind turbine behavior. This paper describes the development process of the project consisting of four phases. During two phases a scaled set-up was used, which enabled iterative optimization of the complex interaction between the mechanical dynamics and the electrical controller of the test-rig. In the final part of the paper the two previously discussed approaches are combined, as it discusses results from the validation of simulation models using measurements performed on the 13.2 MW test-rig. 相似文献
954.
Wouter A. Serdijn Albert C. Van Der Woerd Jan Davidse Arthur H. M. Van Roermund 《Analog Integrated Circuits and Signal Processing》1995,8(2):131-143
This paper discusses the design of low-voltage low-power fully-integratable automatic gain controls. Four different AGCs are presented, all consisting of three elementary building blocks: a controlled amplifier, a comparator and a voltage follower. Their design is treated separately. As an example, the final section describes an automatic gain control for hearing instruments, realized in a bipolar process. 相似文献
955.
Jan Oosterhaven 《Papers in Regional Science》1983,52(1):125-137
For land outside the sea-dikes of the northern part of the province of Friesland five alternative land-reclamation plans have been made. Agricultural organizations and the Province are in favour of the larger plans because of their expected economic benefits, which mainly accrue to arable farming — wholesale and processing. Environmental organizations are against these plans because of the expected damage to the valuable natural environment of the Dutch Shallows. The plans proposed primarily serve regional interests, have large indirect economic effects, and are finally decided upon by central government. It is argued that for an economic evaluation of such projects an integrated interregional cost-benefit and input-output analysis is most adequate. Under the present Dutch administrative and financial lack of decentralization, it appears to make a great difference whether the cost-benefit analyses are made from a regional point of veiw or made from the more usual national standpoint. 相似文献
956.
A bench-scale sequencing batch reactor was used to study factors affecting the endogenous decay of the ammonium oxidizing biomass (AOB) in different operating conditions. AOB decay was very sensitive to oxygen concentration, and increased up to 0.4 d−1 for oxygen concentration of 7 mg O2 L−1. The decay in anaerobic conditions was shown to be very low (0.03 d−1) when compared to literature data.The effect of nitrite and nitrate on AOB decay was also studied. The correlation was quite weak suggesting that both nitrate and nitrite absence had little impact on decay which is contrary to what is typically assumed in some of the existing process models. A simple expression for the decay of AOB was proposed, calibrated and validated using the results of batch kinetic tests and of the continuous sequencing batch reactor monitoring. 相似文献
957.
Identification and chemical characterization of specific organic indicators in the effluents from chemical production sites 总被引:1,自引:0,他引:1
The structural diversity of the wastewater composition was described by the use of detailed non-target screening analyses of industrial effluents from chemical production sites. Determination of the indicative organic compounds acting as potential molecular indicators for industrial emissions from chemical production industries has been possible due to (i) detailed characterisation of industrial contaminants and identification of compounds with high source specificity, (ii) quantitative determination of the organic constituents in the industrial effluents and (iii) the review of their industrial applications. The determination of potential site-specific markers and industrial molecular indicators corresponding to certain production processes (production of starting materials for manufacturing paper and printing inks, powder coatings as well as epichlorohydrin production) was performed in this work.The results of this study allowed significant contributions to the chemical characterisation of industrial contaminants and isolation of indicators that can act as representatives of industrial effluents in the aquatic environment. 相似文献
958.
G+玻璃主题园概念的诞生上海轻工玻璃有限公司计划在上海玻璃工厂的原址上打造一个全新的玻璃博物馆。老园区内分布着30栋不同年代、规模各异的建筑。logon(罗昂)为园区制定了20年的发展策略,并重新命名为G+玻璃主题园区(玻璃、艺术、研究和技术园区)。 相似文献
959.
An investigation into the training of project managers in Denmark is presented, from the early days of basic school education in the form of project work, through to university and postgraduate training and finally on to on-the-job specific training. Examples are given of typical training programmes encountered throughout a project manager's education and future developments are assessed. 相似文献
960.