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991.
1986年,皮埃蒙特兰格区的布拉市(都灵以南50km)举行了一场在当今国际上影响深远的活动:记者卡尔洛·佩特里尼资助ArciGola协会抗议快餐在意大利的蔓延。3年之后,这一广为人知的运动发展成慢食运动。慢食协会兼顾美食与生态:基于其认识到美食与环境、文化、政治之间的根本联系(新美食学的概念),该组织从各领域推动饮食教育,维护食品供应的多样性,并且将可持续的生产者与他们所谓的"联合生产者"——那些了解食品来源和生产途径的受过教育的消费者——联系起来。慢食运动引入的美食学新视角旨在通过保护地区食品多样性以及农业传统来解决可持续性问题,如今,它可以依靠遍布世界150 相似文献
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993.
The aim of this study is to simulate the impact of non-programmable generation sources, in particular wind farms, on the reliability of an electric power system. A probabilistic model has been implemented, to evaluate the influence of wind generation on the amount of secondary/tertiary generating reserve, required in a hydro-thermoelectric system to maintain a certain level of reliability. 相似文献
994.
Carlo Morasso Miriam Colombo Silvia Ronchi Laura Polito Serena Mazzucchelli Diego Monti Marco Buscaglia Tommaso Bellini Davide Prosperi 《Advanced functional materials》2010,20(22):3932-3940
Highly fluorinated materials are being widely investigated due to a number of peculiar properties, which are potentially useful for various applications, including use as lubricants, anti‐adhesive films, and substitutes for biological fluids for biomedical utilization. However, at present such potential is still poorly exploited. One of the major drawbacks that hampers the rapid development of nanoscale fluoro‐hybrid devices is the remarkable inertness of perfluoropolymeric materials that lack reactive functionalities, as they do not offer any functional groups that can be employed to covalently anchor organic molecules on their surface. In this paper, a convenient method for the stable biofunctionalization of strongly unreactive perfluoropolymer nanoparticles (PnPs) is reported. PnPs are easily coated with newly synthesized asymmetric diacetylenic monomer compounds (ADMs), thanks to PnP’s high propensity to interact with hydrophobic moieties. Once monomerically adsorbed onto PnPs, such suitably designed ADMs enable the formation of a robust polymeric shell around the perfluoroelastomer core via a clean UV‐promoted localized photopolymerization. Given the peculiar optical characteristics of PnPs, the coating of the particles can be monitored step by step using light scattering, which also allows estimation of the fraction of reacted monomers by competitive adsorption with smaller particles. The potential of this method for the biofunctionalization of PnPs is demonstrated with representative proteins and carbohydrates. Among them, the extension to avidin–biotin technology may broaden the scope and applicability of this strategy to potentially a large number of molecules of biomedical interest. 相似文献
995.
Daniel Eberli Davide Scaramuzza Stephan Weiss Roland Siegwart 《Journal of Intelligent and Robotic Systems》2011,61(1-4):495-512
This paper presents a real-time vision based algorithm for 5 degrees-of-freedom pose estimation and set-point control for a Micro Aerial Vehicle (MAV). The camera is mounted on-board a quadrotor helicopter. Camera pose estimation is based on the appearance of two concentric circles which are used as landmark. We show that that by using a calibrated camera, conic sections, and the assumption that yaw is controlled independently, it is possible to determine the six degrees-of-freedom pose of the MAV. First we show how to detect the landmark in the image frame. Then we present a geometric approach for camera pose estimation from the elliptic appearance of a circle in perspective projection. Using this information we are able to determine the pose of the vehicle. Finally, given a set point in the image frame we are able to control the quadrotor such that the feature appears in the respective target position. The performance of the proposed method is presented through experimental results. 相似文献
996.
Paolo Rosso Santiago Correa Davide Buscaldi 《The Journal of Logic and Algebraic Programming》2011,80(3-5):139-153
Legal texts usually comprise many kinds of texts, such as contracts, patents and treaties. These texts usually include a huge quantity of unstructured information written in natural language. Thanks to automatic analysis and Information Retrieval (IR) techniques, it is possible to filter out information that is not relevant and, therefore, to reduce the amount of documents that users need to browse to find the information they are looking for. In this paper we adapted the JIRS passage retrieval system to work with three kinds of legal texts: treaties, patents and contracts, studying the issues related with the processing of this kind of information. In particular, we studied how a passage retrieval system might be linked up to automated analysis based on logic and algebraic programming for the detection of conflicts in contracts. In our set-up, a contract is translated into formal clauses, which are analysed by means of a model checking tool; then, the passage retrieval system is used to extract conflicting sentences from the original contract text. 相似文献
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999.
Mariarosa Raimondo Michele Dondi Davide Gardini Guia Guarini Francesca Mazzanti 《Construction and Building Materials》2009,23(7):2623-2630
The effect of product characteristics and processing conditions on the initial rate of water absorption of 15 clay bricks was investigated and the influence of porosimetric parameters (amount, size and tortuosity of pores) as well as of phase composition (amount of calcium-silicates and amorphous phase) was established. The suction behaviour of bricks, which may be brought back to the models of [Gummerson RJ, Hall C, Hoff WD. The suction rate and the sorptivity of bricks. Brit Ceram Trans J 1981;80:150–2.] and [Hoffmann D, Niesel K. Quantifying capillary rise in columns of porous material. Am Ceram Soc Bull 1988;67(8):1418.], was also evaluated on the basis of both the product microstructure and the liquid physical properties. According to the model of Beltran et al. (1988), which reveled to be sufficiently reliable, the values of the capillary coefficient Ks were calculated and their correlation with the experimental ones has been provided. For a given liquid and in the same experimental conditions, the results indicate that varying in a controlled way the product microstructure (i.e. decreasing the pore size, increasing the pore tortuosity and/or controlling the amorphous/new formed phases ratio) should allow to design materials having a most suitable behaviour. 相似文献
1000.