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With the Smart Grid revolution and the increasing interest in renewable energy sources, the management of the electricity consumption and production of individual households and small residential communities is becoming an essential element of new power systems. The electric energy chain can greatly benefit from a flexible interaction with end-users based on the optimization of load profiles and the exploitation of local generation and energy storage. This paper proposes a framework for the development of a complete energy management system for individual residential units and small communities of domestic users, taking into account both the power system and the final users’ perspectives. All the main elements of the framework are considered, and contributions are provided on the users’ habits profiling, electricity generation forecast, energy load, and storage optimization. Specifically, we propose a linear regression model to predict the photovoltaic panels production, a stochastic method to forecast the home appliances usage, and two optimization models to optimize the electricity management of residential users with the goal of minimizing their bills. The study shows that it is possible to reduce the energy bill of residential users through the electricity optimization driven by dynamic energy prices. Moreover, remarkable improvements of the electric grid efficiency can be achieved with the cooperation among users, confirming that services for the coordination of the demand of groups of users allow huge benefits on the power system performance.  相似文献   
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《国际城市规划》(UPI)于2009年出版了一辑专刊,介绍了意大利城市规划的相关情况和背景.意大利是一个具有2 000多年文化创造传统的国度,城市在意大利的发展历程中始终发挥着重要作用.作为一个事实上的城邦国家,意大利的城市发展深受根植于当地的市民文化. 1城市新景象 最近几年,从佛罗里达(Florida)和兰德利(Landry)的著作开始,人们对“创意”这一城市竞争要素的反思和实验交织在一起,引发了对其理论与实践的进一步反省,其目的是为了给创意城市提供更宽阔的空间,付诸实际行动,提高实施效果,改善生活品质.  相似文献   
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Journal of Computer Virology and Hacking Techniques - When designing Wireless Sensor Networks it is important to analyze their security risks and provide adequate solutions for protecting them from...  相似文献   
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How do the new building façade components work under real climatic conditions? The question is especially related to the dynamic behaviour of new and complex components such as the ventilated walls, the Phase Change Material, or others that use nano-technologies and aerogels. One of the objectives of the undergoing research activity, named Abitare Mediterraneo, is the evaluation of their thermal behaviour through the use of an outdoor test cell, in order to reproduce under the real external conditions the performance of these components, and consequently define the main thermal parameters such as the attenuation factor and the thermal inertia, characterising the component; moreover, the results will be used to write new algorithms for dynamic simulation tools allowing an appropriate evaluation of the complex behaviour of the whole building at a real scale condition. The new test cell is realised in Florence, Italy. The design starts from the study of the experience of the existing PASSYS test cells, overtaking the main weakness of the building structure and of the heat-flux sensors.  相似文献   
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Glass-ceramics (GCs) are multiphase micro- or nano-crystalline materials produced by the controlled nucleation and crystallization of an amorphous glass through a proper heating or chemical process. Most optical applications require transparency, and this usually implies that the crystalline phase be made of nanocrystals. Transparent GCs are able to combine the advantages of all their components, glasses, and crystals. Incorporation of semiconducting, ferroelectrical, and nonlinear optical phases in glass matrices can produce very promising materials for different applications. A very important role is played by nanocrystals which are activated by luminescent species, as rare earth ions. The presence of the crystalline environment around a rare earth ion allows high absorption and emission across sections, and reduction in the nonradiative relaxations thanks to the lower phonon cut-off energy. Such materials may lead to real advances in optical amplifiers, up-conversion fibers, solid-state lasers, medical sensors, and several other devices, especially if combined with a guided-wave configuration, which allows high energy densities and efficient delivery of the transmitted optical beams. The present review article covers the properties and current state of transparent glass-ceramics for guided-wave devices, including the discussion of the preparation methods and of their spectral and luminescent properties.  相似文献   
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High‐Energy Ball Milling (HEBM) is proposed as a cost effective and environmental friendly technique to produce Co‐ and Mn‐ based oxides suitable for application as protective coating. Mixtures of manganese and cobalt oxides in different molar ratio (Co:Mn = 1:1 and Co:Mn = 2:1) were subjected to mechanochemical treatment up to 100 h and morpho‐structural evolution was evaluated. XRD analysis results show that the HEBM treatment promotes the solid‐state reaction of the starting compounds, with the formation of different crystalline phases when compared to high‐temperature solid‐state synthesis. SEM observations and N2 adsorption measurements suggest that all processed powders are composed by aggregates of nanometric particles. While long milling time is required to complete the reaction, 10 hours are enough to activate the powders to obtain the desired phases after a mild thermal treatment, as evidenced by in situ thermal XRD analysis. Electrical conductivity measures performed with the Van der Pauw method on sintered pellets evidence a significant difference between the two compositions, related to the dual‐phase nature of Co:Mn = 1:1 material at intermediate temperatures (i.e., T < 700°C), Co:Mn = 2:1 sample showing higher conductivity values in the whole tested range (500°C–800°C).  相似文献   
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[Correction Notice: An erratum for this article was reported in Vol 18(3) of Experimental and Clinical Psychopharmacology (see record 2010-11933-011). In the article the authors find it necessary to redefine the thresholding procedure used for data analyses, due to problems in the Brain Voyager software. This does not affect the main findings of the paper.] Reactivity to smoking-related cues may play a role in the maintenance of smoking behavior and may change depending on smoking status. Whether smoking cue-related functional MRI (fMRI) reactivity differs between active smoking and extended smoking abstinence states currently is unknown. We used fMRI to measure brain reactivity in response to smoking-related versus neutral images in 13 tobacco-dependent subjects before a smoking cessation attempt and again during extended smoking abstinence (52 ± 11 days) aided by nicotine replacement therapy. Prequit smoking cue induced fMRI activity patterns paralleled those reported in prior smoking cue reactivity fMRI studies. Greater fMRI activity was detected during extended smoking abstinence than during the prequit assessment subcortically in the caudate nucleus and cortically in prefrontal (BA 6, 9, 44, 46), primary somatosensory (BA 1, 2, 3), temporal (BA 22, 41, 42), parietal (BA 7, 40) anterior cingulate (BA 24, 32), and posterior cingulate (BA 31) cortex. These data suggest that during extended smoking abstinence, fMRI reactivity to smoking versus neutral stimuli persists in brain areas involved in attention, somatosensory processing, motor planning, and conditioned cue responding. In some brain regions, fMRI smoking cue reactivity is increased during extended smoking abstinence in comparison to the prequit state, which may contribute to persisting relapse vulnerability. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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