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Leila Sharifi Llorenç Cerdà-Alabern Felix Freitag Luís Veiga 《Journal of Grid Computing》2016,14(2):299-325
The cost of power and its associated delivery are becoming significant factors in the total expenditure of large-scale data centers. Numerous techniques have been proposed to address the energy efficiency issue in cloud systems. Recently, some efforts have been made to decentralize the cloud via distributing data centers in diverse geographical positions, at different scales. In this paper, we elaborate on the energy effectiveness of service provisioning on different cloud architectures, from a mega-data center to a nano data center, which provides the extreme decentralization in terms of cloud architecture, as well as P2P-clouds or community network clouds. We study the energy consumption through an analytical and simulation framework for video streaming and MapReduce applications. 相似文献
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Irena Borovanska María L. Cerrada Peter Zipper 《Polymer-Plastics Technology and Engineering》2016,55(5):486-497
The purpose of this study is to investigate the effect of treated natural zeolite on the flow behavior, morphology, thermal, and mechanical properties in recycled polyolefin blends. A model polymer blend consisting of 95 wt% polyolefines and 5 wt% polystyrene was studied. Compositions from this recycled blend and dehydrated zeolite in a narrow concentration range (0–5 wt%) were treated with maleic anhydride-grafted polypropylene and initiator dicumyl peroxide. The compositions were characterized by capillary rheometry, wide-angle X-ray scattering, differential scanning calorimetry, scanning electron microscopy, and mechanical tests. The results show a compatibilizing effect of treated zeolite expressed by increase of shear viscosity and improvement of interfacial interactions and impact strength. The results can open wide possibilities for utilization of treated zeolite in recycling of unsorted polymer wastes. 相似文献
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Building sustainability assessment tools (BSATs) aim to promote and rank the sustainability of building stock. This paper makes a deep comparative analysis on how dwellings are evaluated by five BSAT and one performance-based design tool. The comparison is based on: (i) the purpose of assessment; (ii) sustainability dimensions considered; (iii) indicators addressed; (iv) life cycle phases considered by the indicators; (v) type of indicators; (vi) measurements; (vii) aggregation processes; and (vii) life cycle phases during which the assessment was carried out. The evaluation showed that the scope of BSAT varies significantly as well as the life cycle phases addressed in the assessment. Financial issues are often excluded from the assessment. None of the schemes is totally quantitative or qualitative in their measurement system; all have different types of indicators and different ways to assess them. This research provides researchers and stakeholders with important inside knowledge on the tools that allow the development and construction of more sustainable buildings. 相似文献
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A. Mendizabal J. B. González-Díaz M. San Sebastián A. Echeverría 《Journal of Materials Engineering and Performance》2016,25(7):2670-2678
This paper describes the implementation of a simple strategy adopted for the inherent shrinkage method (ISM) to predict welding-induced distortion. This strategy not only makes it possible for the ISM to reach accuracy levels similar to the detailed transient analysis method (considered the most reliable technique for calculating welding distortion) but also significantly reduces the time required for these types of calculations. This strategy is based on the sequential activation of welding blocks to account for welding direction and transient movement of the heat source. As a result, a significant improvement in distortion prediction is achieved. This is demonstrated by experimentally measuring and numerically analyzing distortions in two case studies: a vane segment subassembly of an aero-engine, represented with 3D-solid elements, and a car body component, represented with 3D-shell elements. The proposed strategy proves to be a good alternative for quickly estimating the correct behaviors of large welded components and may have important practical applications in the manufacturing industry. 相似文献
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Bacterial polysaccharides and polyhydroxyalkanoates present physical and chemical characteristics that impart them diverse functional properties, including the ability to produce structures from nano- to macroscale (e.g., spheres, capsules, beads). Such structures may be specially designed to fulfill the requirements of specific applications in different areas, either alone or conjugated with other polymers by means of ionic interactions, hydrogen bonding, or chemical reactions. The interest on using such biomaterials has been increasing due to their unique functional properties, nontoxicity, biodegradability, and biocompatibility. The fields of application of bacterial polymers-based structures include drug delivery, biomedicine, food products, environment, and agriculture, among others. 相似文献
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In this article we present Ethane, a parallel heterogeneous metaheuristic model specifically designed for its execution on heterogeneous hardware environments. With Ethane we propose a hybrid parallel search algorithm inspired in the structure of the chemical compound of the same name, implementing a heterogeneous island model based in the structure of the chemical bonds of the ethane compound. Here we also shape a schema for describing a complete family of parallel heterogeneous metaheuristics inspired by the structure of hydrocarbons in nature, HydroCM (HydroCarbon inspired Metaheuristics), establishing a resemblance between atoms and computers, and between chemical bonds and communication links. Our goal is to gracefully match computers of different computing power to algorithms of different behavior (genetic algorithm and simulated annealing in this study), all them collaborating to solve the same problem. In addition to the nice natural metaphor we will show that Ethane, though simple, can solve search problems in a faster and more robust way than well-known panmictic and distributed algorithms very popular in the literature, as well as can achieve a better exploration/exploitation balance during the search process. 相似文献