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101.
Multicarrier energy systems: Optimization model based on real data and application to a case study
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Multicarrier energy systems are increasingly used for a number of applications, among which the supply of electricity, heating, and cooling in buildings. The possibility of switching between different energy sources is a crucial advantage for the optimal fulfillment of the energy demand. The flexibility of these systems can benefit from the integration with smart grids, which have strong variations in time during their operation. The energy price is the parameter that is usually considered, but also the primary energy factor and the greenhouse gases emissions need to be accounted. This paper presents an application of an operational optimization method for a multicarrier energy system, based on real data–driven model and applied to different countries. The generation plant of a hospital is considered as case study, coping with multiple energy needs by relying on different conversion technologies. The optimal operation of the system shows a wide range of variability, depending on the chosen objective function, the hour of the day, the season, and the country. The results are affected mostly by the energy mix of the electricity supplied from the power grid, which has a direct influence on the primary energy consumption and the greenhouse gases emissions and an indirect influence on the electricity prices. 相似文献
102.
Kholdeeva Oxana A. Ivanchikova Irina D. Maksimchuk Nataliya V. Melgunov Maxim S. Chang Jong-San Guidotti Matteo Shutilov Alexei A. Zaikovskii Vladimir I. 《Topics in Catalysis》2014,57(17):1377-1384
Catalytic properties of Ti-containing porous solids were compared in the oxidation of 2,3,6-trimethylphenol (TMP) with H2O2 to produce 2,3,5-trimethyl-1,4-benzoquinone (TMBQ, vitamin E key intermediate). Mesoporous titanium–silicates with di(oligo)nuclear Ti centers, metal–organic framework MIL-125 and amorphous TiO2 demonstrated 100 % selectivity toward TMBQ. Titanium–silicates prepared by evaporation-induced self-assembly revealed superior performance in terms of product yield and catalyst reusability.
相似文献103.
Simone Ceriani Giulio Fontana Alessandro Giusti Daniele Marzorati Matteo Matteucci Davide Migliore Davide Rizzi Domenico G. Sorrenti Pierluigi Taddei 《Autonomous Robots》2009,27(4):353-371
A trustable and accurate ground truth is a key requirement for benchmarking self-localization and mapping algorithms; on the
other hand, collection of ground truth is a complex and daunting task, and its validation is a challenging issue. In this
paper we propose two techniques for indoor ground truth collection, developed in the framework of the European project Rawseeds, which are mutually independent and also independent on the sensors onboard the robot. These techniques are based, respectively,
on a network of fixed cameras, and on a network of fixed laser scanners. We show how these systems are implemented and deployed,
and, most importantly, we evaluate their performance; moreover, we investigate the possible fusion of their outputs. 相似文献
104.
Kaulich B Wilhein T Di FE Romanato F Altissimo M Cabrini S Fayard B Susini J 《Journal of the Optical Society of America. A, Optics, image science, and vision》2002,19(4):797-806
X-ray imaging in differential interference contrast (DIC) with submicrometer optical resolution was performed by using a twin zone plate (TZP) setup generating focal spots closely spaced within the TZP spatial resolution of 160 nm. Optical path differences introduced by the sample are recorded by a CCD camera in a standard full-field imaging and by an aperture photodiode in a standard scanning transmission x-ray microscope. Applying this x-ray DIC technique, we demonstrate for both the full-field imaging and scanning x-ray microscope methods a drastic increase in image contrast (approximately 20x) for a low-absorbing specimen, similar to the Nomarski DIC method for visible-light microscopy. 相似文献
105.
Formal methods have been proved successful in analyzing different kinds of security protocols. They typically formalize and study the security guarantees provided by cryptographic protocols, when executed by a (possibly unbounded) number of different participants. A key problem in applying formal methods to cryptographic protocols, is the study of multi-protocol systems, where different protocols are concurrently executed. This scenario is particularly interesting in a global computing setting, where several different security services coexist and are possibly combined together. In this paper, we discuss how the tagging mechanism presented in [M. Bugliesi, R. Focardi, and M. Maffei. Compositional analysis of authentication protocols. In Proceedings of European Symposium on Programming (ESOP 2004), volume 2986 of Lecture Notes in Computer Science, pages 140–154. Springer-Verlag, 2004, M. Bugliesi, R.Focardi, and M.Maffei. A theory of types and effects for authentication. In ACM Proceedings of Formal Methods for Security Engineering: from Theory to Practice (FMSE 2004), pages 1–12. ACM Press, October 2004] addresses this issue. 相似文献
106.
Legnani P Leoni E Rapuano S Turin D Valenti C 《International journal of food microbiology》1999,53(2-3):153-158
A 5-year study was carried out on the growth curve of two strains of P. aeruginosa inoculated at a density of 10(2) cfu/ml into samples of natural mineral water with different levels of dissolved solids (TDS at 180 degrees C: 72.5 and 382 mg/l) and low organic content (TOC: 0.17 and 0.35 mg/l). The resulting growth curves were similar for both strains, with only slight differences depending on the different amounts of dissolved solids in the water. After 4-5 days counts were increased by 3 log units. This level was maintained until 70-100 days from inoculation, after which a slow decrease began, culminating in the death of one of the strains after 5 years. No difference in recovery was observed between the method using direct inoculation on Cetrimide Agar and the resuscitation technique (preincubation in Tryptone Soya Agar followed by inoculation on Cetrimide Agar) in the exponential phase of the growth curve. During the stationary and death phases, however, the enrichment technique gave statistically slightly higher counts than the selective technique, indicating the presence of damaged P. aeruginosa cells. The use of a resuscitation step when using Cetrimide Agar to assess bottled water quality is recommended. 相似文献
107.
108.
Polymerization processes are probably the most relevant example of a chemical reaction activated by catalysts or radical initiators. Among polymers, polyethylene is by far the most common and largely produced. Here we present a high-pressure synthesis of high-density crystalline polyethylene by using only physical tools such as pressure and light. Low-density polyethylene is obtained by compressing ethylene at room temperature above 3 GPa in the ordered crystal phase, and a highly crystalline polymer is produced in the fluid phase at pressures lower than 1 GPa by using continuous-wave laser lines (lambda < or = 460 nm) as an optical catalyst. The photo-activation is based on a two-photon absorption process to pi* antibonding states, where the change in molecular geometry favours the polymeric chain formation. The high yield and crystallinity of the polymer recovered by the photoinduced reaction and the simplicity of the synthesis make this process appealing for large-scale applications. 相似文献
109.
In information retrieval systems storage occupancy is in general disregarded to take advantage in running time; in an environment
in which retrieval time is not a primary requirement (this is the case of Data Base Machines), transposed files become a very
interesting structure; in fact they allow a considerable space saving with respect to fast access structures, such as inverted
files. But transposed files, in most cases, are not practicable, as theyare to be searched by a sequential scanning.
In this paper a structure is defined to implement transposed files, called 2-B tree, which is a sort of two-dimensionalB-tree, and avoid sequential scanning; search in a trasposed file stored as a 2-B tree in π memory pages is 0 (π1/2), while insertion and deletion are 0 (logπ). Moreover, 2-B tree organization can achieve an improvement in storage requirements up to 42% with respect to inverted file organization.
相似文献
110.
Characterization of microstructured optical fibers for wideband dispersion compensation 总被引:4,自引:0,他引:4
Poli F Cucinotta A Fuochi M Selleri S Vincetti L 《Journal of the Optical Society of America. A, Optics, image science, and vision》2003,20(10):1958-1962
Microstructured optical fibers (MOFs) with small hole-to-hole spacing and large airholes are designed to compensate the anomalous dispersion and the dispersion slope of single-mode fibers. The geometrical parameters that characterize triangular MOFs are chosen to optimize the fiber length and the compensation over a wide wavelength range. A proper design of the photonic crystal fiber geometry allows us to achieve dispersion values of approximately -1700 ps nm(-1) km(-1) at 1550 nm and to compensate the dispersion of standard fibers within +/- 0.5 ps nm(-1) km(-1) over a 100-nm range. The MOF dispersion properties have been studied by means of a numerical simulator for modal analysis based on the finite-element method. 相似文献