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排序方式: 共有1497条查询结果,搜索用时 31 毫秒
81.
Roberta Ansuini Roberto Larghetti Alberto Giretti Massimo Lemma 《Energy and Buildings》2011,43(11):3019-3026
The control of indoor thermal comfort in buildings through thermal inertia during the summer season plays a fundamental role in the design of energy efficient buildings, especially in the Mediterranean climate. In fact, lightweight, highly insulated buildings cannot provide the necessary mass to buffer thermal gains. Phase change materials (PCM) have been used to provide lightweight building components with the required thermal inertia without increasing their overall mass. So far the integration of PCM into lightweight piped radiant floors for the control of thermal comfort during summer cooling regimes has not been investigated. This paper reports the development of a lightweight piped radiant floor prototype with an integrated PCM layer aimed at buffering internal gains at constant temperature during summer cooling regimes without affecting its winter warming capacity. Both the construction of the laboratory specimens and the development of the optimized finite element models are detailed and the assessment of the floor performance in a simulated room is discussed. 相似文献
82.
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84.
The Rovereto Emotion and Cooperation Corpus (RECC) is a new resource collected to investigate the relationship between cooperation
and emotions in an interactive setting. Previous attempts at collecting corpora to study emotions have shown that this data
are often quite difficult to classify and analyse, and coding schemes to analyse emotions are often found not to be reliable.
We collected a corpus of task-oriented (MapTask-style) dialogues in Italian, in which the segments of emotional interest are
identified using psycho-physiological indexes (Heart Rate and Galvanic Skin Conductance) which are highly reliable. We then
annotated these segments in accordance with novel multimodal annotation schemes for cooperation (in terms of effort) and facial
expressions (an indicator of emotional state). High agreement was obtained among coders on all the features. The RECC corpus
is to our knowledge the first resource with psycho-physiological data aligned with verbal and nonverbal behaviour data. 相似文献
85.
86.
Michele Dei Nicolò Nizza Massimo Piotto Paolo Bruschi 《Analog Integrated Circuits and Signal Processing》2009,58(1):43-47
A compact voltage controlled CMOS current divider is presented. Differently from previous implementations, exploiting the
MOSFET translinear characteristics in subthreshold region, the proposed circuit is based on devices operating from moderate
to strong inversion. An input current linearity range of nearly a decade is obtained by compensating for the deviations from
the ideal drain current square-law approximation through an original empirical approach. The circuit is suitable for use as
a building block in analog multipliers and for transconductor continuous tuning. The effectiveness of the proposed configuration
is demonstrated by means of electrical simulations, performed on a prototype designed with a commercial process. The robustness
of the linearization algorithm with respect to temperature variations is proven. 相似文献
87.
Since the beginning of the 20th century, in Italy as in many other countries, reinforced concrete (RC) became one of the most popular construction materials and it was used for buildings, monuments, infrastructures, etc. Several of these structures, although of recent formation, have now been included in the cultural heritage, because of their architectural or social relevance. As a consequence of the typical urban or rural exposure conditions of these buildings, they often suffer damage due to carbonation‐induced corrosion of reinforcement, such as concrete spalling or cracking or rust stains that may affect the serviceability of structures. Furthermore, chloride‐induced corrosion of reinforcement, may also concern buildings exposed to de‐icing salts or marine environments. Due to strict requirements related to the preservation of the original materials and texture, the repair of structures that belong to the cultural heritage cannot rely on the conventional repair technique, based on the replacement of carbonated concrete. Therefore, the conservation of RC buildings of the cultural heritage is a challenge, since it requires the development of specific strategies aimed at finding the best compromise between, on one hand, the restoration of structural safety and the prevention of future damage and, on the other hand, the preservation of the original materials and surfaces. This paper analyses the results of inspections carried out on several buildings, built in Italy throughout the 20th century in different micro‐ and macro‐climates, with the aim of showing their peculiarities with regard to steel corrosion and the selection of restorations strategies. 相似文献
88.
Stefano Mercati Massimo MilaniLuca Montorsi Fabrizio Paltrinieri 《International Journal of Hydrogen Energy》2013
The working cycle of a novel hydrogen and power generation system based on aluminum combustion with water is analyzed in order to evaluate the best performance in terms of energy conversion efficiency. The system exploits the exothermic reaction between aluminum and steam and produces thermal power for a super-heated steam cycle and hydrogen as a by-product of the reaction. 相似文献
89.
Massimo Merro 《Information and Computation》2009,207(2):194-208
We propose a process calculus to study the behavioural theory of Mobile Ad Hoc Networks. The operational semantics of our calculus is given both in terms of a Reduction Semantics and in terms of a Labelled Transition Semantics. We prove that the two semantics coincide. The labelled transition system is then used to derive the notions of (weak) simulation and bisimulation for ad hoc networks. The labelled bisimilarity completely characterises reduction barbed congruence, a standard branching-time and contextually-defined program equivalence. We then use our (bi)simulation proof method to formally prove a number of non-trivial properties of ad hoc networks. 相似文献
90.
Roberto Cigliutti Andrea Galtarossa Massimo Giltrelli Daniele Grosso Andrew W.R. Leitch Luca Palmieri Stefano Santoni Luca Schenato David Waswa 《Optical Fiber Technology》2009,15(3):242-250
Polarization Mode Dispersion (PMD) compensation has been a matter of investigation of several papers in literature. The proposed solutions belong basically to two large families: electronic compensators and optical compensators. Both PMD compensator schemes have advantages and disadvantages: electronic PMD compensators are usually simple to include in line-terminal, potentially low-cost, very fast, and FEC compatible but their development is strongly dependent on IC technology capability that at this time allows device developments up to the 10 Gbit/s bit rates area. Furthermore, they are strongly dependent on modulation formats, and they can operate only on a single channel. Conversely, optical compensators are independent of bit rate and modulation format and potentially they can compensate more channels simultaneously; their major drawbacks are the longer response time and the complexity in the feedback signal process within the control algorithm. In this paper we consider an optical Polarization Mode Dispersion Compensator (PMDC) that is simple to realize and easy to include at limited costs in each EDFA module (distributed compensation) as well as a single-stage front-end compensator. Numerical analysis of the PMDC and experimental results confirm the utility of the PMDC proposed and its capability in compensating DGD larger than 20 ps in NRZ and RZ 40 Gbit/s optical systems. 相似文献