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Much research has been conducted on the use of sketch maps to search in spatial databases, nevertheless, they have faced challenges, such as modeling of the data abstraction level, aggregated features in sketches, modeling of semantic aspects of data, data redundancy, and evaluation of the results. Considering these challenges, in this article a new solution is presented for searching in databases based on data matching. The main difference between this solution and the other approaches lies in the parameters introduced to match data and how to solve the matching problem. Using geometrical, topological, and semantic parameters in the matching, as well as performing the matching process in the two phases of partial and global, has resulted in an of about 78%. The evaluation process is performed based on the matching parameters and the matching procedure; finally, the result is acceptable compared to previous implementations. 相似文献
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Life cycle analysis (LCA) methodology was used to perform a quantitative, comparative analysis and rating of the construction and operation of a wind energy plant. For this case study, the Glacier Hills Wind Park (90 1.8-MW turbines in south-central Wisconsin) was evaluated. Significant environmental and economic benefits are often advertised with the installation of new wind energy facilities, although independent and comprehensive LCA and sustainable energy science are typically not implemented. Hence, a quantitative demonstration with LCA methodology of the life cycle emissions and environmental impact, from construction through operations, can greatly assist in highlighting significant areas of energy consumption and emissions during manufacturing, transportation, and construction of a wind farm. Results portray the amount of greenhouse gas emissions and energy consumption/generation over the life cycle of the wind park. Transportation of large components from overseas led to the consumption of considerable quantities of fossil fuel, responsible for up to 22 % of the total greenhouse gas emissions due to transportation. The energy payback ratio (25.5), energy payback time (12.3 months) and the total grams of equivalent CO2(eq) per kWh of energy (16.9) produced were calculated over the life time of this onshore wind farm. 相似文献
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A cloud point extraction procedure is presented for the preconcentration and simultaneous determination of Ag+ and Pd2+ in various samples. After complexation with 2‐((2‐((1H‐benzo[d]imidazole‐2‐yl)methoxy)phenoxy)methyl)‐1H‐benzo[d]imidazol (BIMPI), which was used as a new chelating agent, analyte ions were quantitatively extracted to a phase rich in Triton X‐114 following centrifugation, and determination was carried out by flame atomic absorption spectrometry (FAAS). Under the optimum experimental conditions (i. e., pH = 7.0, 15.0·10–5 mol/L BIMPI and 0.036% (w/v) Triton X‐114), calibration graphs were linear in the range of 28.0–430.0 μg/L and 57.0–720.0 μg/L with detection limits of 10.0 and 25.0 μg/L for Ag+ and Pd2+, respectively. The enrichment factors were 35.0 and 28.0 for Ag+ and Pd2+, respectively. The method has been successfully applied to evaluate these metals in some real samples, including waste water, soil and hydrogenation catalyst samples. 相似文献
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