22 research outputs found

    Challenges in Partially-Automated Roadway Feature Mapping Using Mobile Laser Scanning and Vehicle Trajectory Data

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    Connected vehicle and driver's assistance applications are greatly facilitated by Enhanced Digital Maps (EDMs) that represent roadway features (e.g., lane edges or centerlines, stop bars). Due to the large number of signalized intersections and miles of roadway, manual development of EDMs on a global basis is not feasible. Mobile Terrestrial Laser Scanning (MTLS) is the preferred data acquisition method to provide data for automated EDM development. Such systems provide an MTLS trajectory and a point cloud for the roadway environment. The challenge is to automatically convert these data into an EDM. This article presents a new processing and feature extraction method, experimental demonstration providing SAE-J2735 map messages for eleven example intersections, and a discussion of the results that points out remaining challenges and suggests directions for future research.Comment: 6 pages, 5 figure

    Effect of Calcination Temperature on Catalytic Activity of Synthesis SrO/S-ZrO2 by Solvent-free Method in Esterification of Oleic Acid

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    Currently, the major concern in production of biodiesel fuel is to exploit new catalysts with the optimal conditions. In this study, the effect of calcination temperature on the synthesis of 20 mol % SrO/S-ZrO2 was examined by solvent-free method. Moreover, the ability of the catalyst for esterification reaction of oleic acid with methanol was also assessed. To obtain this objective, X-ray diffraction and infra-red spectroscopy method was employed to characterize the structure of the catalysts. The results of this study reveal that the calcined strontium oxide promoted sulfated zirconia at 500 °C has the highest percentage of tetragonal phases of zirconia. It has also been demonstrated that owing to the high percentage of the tetragonal phases of zirconia and the acidity of the catalyst, conversion of oleic acid to fatty acids methyl esters (i.e., FAME) could be enhanced from 88.36 % to 91.13 %. Moreover, it has also been shown that 20 mol % SrO/S-ZrO2 exhibits higher activity in comparison with S-ZrO2 at 500 °C in esterification reaction due to the presence more sulfate ions and higher activity of strontium ions

    Preparation of Nano-Size Al-Promoted Sulfated Zirconia and the Impact of Calcination Temperature on Its Catalytic Activity

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    Solvent-free technique was employed in this work in order to assess the influence of the calcination temperature on the activity of Al-promoted sulfated zirconia. The catalyst was analyzed by XRD and IR-spectrum method, and catalytic activity was examined by esterification reaction of oleic acid. XRD analysis revealed that a decline in the percentage of tetragonal phases of zirconia was observed by increasing the calcination temperature from 500 to 900 °C. In addition, a reduction of sulfate groups as SO42– on zirconia surface was observed. As a consequence, a decline in Brønsted sites with calcinationtemperature enhancement also prevailed. Therefore, the size of Al-promoted sulfated zirconia particles was increased accordingly. On the other hand, with the aluminum sulfate loading, the amount of sulfate ions on Al-promoted sulfated zirconia surface was enhanced and a reduction in particle size of Al2O3/S-ZrO2 was also observed, as compared to non-promoted. The result of this study revealed that an increase of sulfate and alumina groups causes a raise in the acidity of catalyst. Furthermore, the calcined Al-promoted and non-promoted sulfated zirconia would convert 96.10 % and 89.36 % of oleic acid to biodiesel, respectively. Therefore, Al2O3/S-ZrO2 as a catalyst exhibits a higher activity than S-ZrO2

    Preparation of Supported Nanosized Sulfated Zirconia by Strontia and Assessment of Its Activities in the Esterification of Oleic Acid

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    The aim of this study was to examine a new nanocatalyst of SrO/S-ZrO2 in esterification reaction and the optimum value of strontia loading over the sulfated zirconia. The sulfated zirconia was supported with different molar ratios of strontia in the range of 0.0–0.30, using the solvent-free method. The samples were characterized using XRD, FT-IR, BET and TEM analysis and their activity were investigated in esterification reaction of oleic acid. The findings of this study revealed that 25 mol % SrO/S-ZrO2 had the highest yield in the esterification reaction. It was also concluded that strontia-supported sulfated zirconia could improve the low reusability of the catalyst. Furthermore, 95 % conversion was also obtained at optimized conditions (i.e., 100 °C, 2 wt. % of catalyst, 6:1 molar ratio of methanol/oleic acid and for a period of 30 minutes)

    Dewatering of Yoghurt Using Permeable Membrane and Acrylic Superabsorbent Hydrogel

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    Conventional processes of food dewatering, such as thermal, have undesirable and destruction effects on vitamins, aromatic compounds and pigments. In addition, they are accompanied with some technological complications and energy consumption. Thus, food concentration processes are directed to non-thermal techniques or methods with reduced heat effects. Superabsorbents are highly hydrophilic polymer networks which can absorb water and aqueous solutions some hundred times of their weights and retain them. These materials are subgroups of hydrogel family that are transformed into gels after absorbing water. In the present research, the possibilities of yoghurt dewatering using superabsorbents have been investigated for the first time in Iran and some remarkable results are obtained for this vital product. In the experiments carried out to investigate the effect of these absorbents on normal method of yoghurt concentration (use of permeable membrane), type of bed (wide and vertical) and time are also studied. The percentage of total soluble solids and dry solids of dewatered samples were measured in different time intervals up to 180 min. The results showed that superabsorbent on a wide bed would reduce the concentration time to one third. In other words, in a certain time interval, more than 70% increase in yoghurt dry solids was observed compared to normal method. These results show that acrylic superabsorbent hydrogel can be applied as highly hydrophilic material in non-thermal food dewatering methods
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