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81.
One of the common transportation systems in Korea is calling taxis through online applications, which is more convenient for passengers and drivers in the modern area. However, the driver's passenger taxi request can be rejected based on the driver's location and distance. Therefore, there is a need to specify driver's acceptance and rejection of the received request. The security of this system is another main core to save the transaction information and safety of passengers and drivers. In this study, the origin and destination of the Jeju island South Korea were captured from T-map and processed based on machine learning decision tree and XGBoost techniques. The blockchain framework is implemented in the Hyperledger Fabric platform. The experimental results represent the features of socio-economic. The cross-validation was accomplished. Distance is another factor for the taxi trip, which in total trip in midnight is quite shorter. This process presents the successful matching of ride-hailing taxi services with the specialty of distance, the trip request, and safety based on the total city measurement. 相似文献
82.
Babasafari Zeinab Pan Alexey V. Pahlevani Farshid Kong Charlie Du Toit Madeleine Dippenaar Rian 《Metallurgical and Materials Transactions A》2021,52(11):5107-5122
Metallurgical and Materials Transactions A - Industrially produced high-carbon steel has been heat treated in order to obtain various microstructures of the single phase of martensite, bainite,... 相似文献
83.
The key challenge of extracting oil from oil sand reservoirs is the viscosity of the oil which is typically between 100 000 and several million cP. To reduce the viscosity of the oil, high pressure, high temperature steam, typically between about 185 and 250 °C, is injected into the reservoir by using recovery processes such as the steam‐assisted gravity drainage (SAGD) process. In this process, steam heats the bitumen and as a consequence, its viscosity drops to about 5 cP and it readily flows under gravity within the reservoir. One key issue that has not gained much attention with respect to SAGD process evolution are steam–rock reactions, water geochemistry, and how the produced water composition varies as the process evolves. Here, we examine how the produced water composition varies in SAGD operations. For the first time, we show that the produced water composition can be used to detect shale barriers and contact of the steam chamber with the overburden. As yet, the produced water composition is not used to understand in situ process development but as we show here, this could be a rich data source for understanding process dynamics. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
84.
Molecular Recognition of Two 2,4‐syn‐Functionalized (S)‐Glutamate Analogues by the Kainate Receptor GluK3 Ligand Binding Domain
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Dr. Raminta Venskutonytė Anja P. Larsen Dr. Karla Frydenvang Prof. Michael Gajhede Dr. Emmanuelle Sagot Dr. Zeinab Assaf Dr. Thierry Gefflaut Dr. Darryl S. Pickering Dr. Lennart Bunch Prof. Jette S. Kastrup 《ChemMedChem》2014,9(10):2254-2259
The kainate receptors are the least studied subfamily of ionotropic glutamate receptors. These receptors are thought to have a neuromodulatory role and have been associated with a variety of disorders in the central nervous system. This makes kainate receptors interesting potential drug targets. Today, structures of the ligand binding domain (LBD) of the kainate receptor GluK3 are only known in complex with the endogenous agonist glutamate, the natural product kainate, and two synthetic agonists. Herein we report structures of GluK3 LBD in complex with two 2,4‐syn‐functionalized (S)‐glutamate analogues to investigate their structural potential as chemical scaffolds. Similar binding affinities at GluK3 were determined for the 2‐(methylcarbamoyl)ethyl analogue (Ki=4.0 μM ) and the 2‐(methoxycarbonyl)ethyl analogue (Ki=1.7 μM ), in agreement with the similar positioning of the compounds within the binding pocket. As the binding affinity is similar to that of glutamate, this type of Cγ substituent could be used as a scaffold for introduction of even larger substituents reaching into unexplored binding site regions to achieve subtype selectivity. 相似文献
85.
A clean, simple and efficient method for the synthesis of 3,3′-(arylmethylene)bis(2-hydroxynaphthalene-1,4-dione) derivatives has been developed which uses the reaction of 2-hydroxynaphthalene-1,4-dione and aromatic aldehydes in the presence of a catalytic amount of LiCl in aqueous media. To the best of our knowledge, this is the first report on such a synthesis of 3,3′-(arylmethylene)bis(2-hydroxynaphthalene-1,4-dione). 相似文献
86.
M. Bavand-Vandchali H. Sarpoolaky F. Golestani-Fard H.R. Rezaie 《Ceramics International》2009,35(2):861-868
The effects of carbon, air and reducing atmospheres on microstructure and phase evolution of in situ MgAl2O4 spinel (S) formation in the matrix of MgO–C refractories were investigated by X-ray diffraction powder analysis (XRD) and scanning electron microscopy (SEM)/energy-dispersive spectroscopy (EDS) techniques. The formation of spinel started under 1000 °C in both air and reducing atmospheres. The morphology of in situ spinel and its formation mechanism were however different and dependent upon the atmosphere. The solid-state reaction was clarified to be the dominant mechanism of spinel formation in oxide atmosphere, while the gas–solid reaction was found to play a vital role in reducing atmosphere. Reaction of MgO and C in reducing atmosphere led to the formation of Mg(g) which was found to be partially controlling the in situ spinel formation in the carbon containing samples fired in reducing environment. The results which were necessary are explained with emphasis on MgO–C refractories applications. 相似文献
87.
H.R. Rezaie R. Naghizadeh N. Farrokhnia S. Arabi M. sobhani 《Ceramics International》2009,35(2):679-684
Aluminium titanate (Al2TiO5) exhibits interesting properties, such as low thermal expansion, high thermal shock resistance, high refractoriness, and good corrosion resistance. In this research, effect of hematite (Fe2O3) addition on the formation temperature of Al2TiO5 was studied starting from very fine (micronsized) rutile (TiO2) and aluminum hydrate (Al(OH)3) powders. Samples with (0, 2.5, 5, 7.5, and 10) wt.% hematite were prepared for comparison. Identification of phases was accomplished using X-ray diffraction. The samples were characterized by simultaneous thermal analysis and microstructural analysis using scanning electron microscopy. The addition of Fe2O3 changes the mechanism of tialite formation. The main results are reduction in tialite formation temperature down to 1150 °C, tialite grains growth, and decrease of porosity. 相似文献
88.
Three-dimensional profilometric object reconstruction is a challenging topic; among the various methods available, we implement the line projection technique, which has superiorities over other methods. In order to increase the accuracy of measurement, a wavelet transform analysis is used in two stages of denoising and phase extraction. Because of the denoising capability and multiresolution characteristics of wavelet transforms, we employ an undecimated wavelet transform for noise reduction and a continuous wavelet transform in the phase extraction stage. The aim is to add a preprocessing stage of denoising based on the undecimated wavelet transform to enhance the accuracy of measurement in noisy patterns. The experimental results on the human face as a complex object demonstrate that the combination of undecimated and continuous wavelet transforms could increase measurement accuracy in noise-contaminated patterns. 相似文献
89.
Zeinab Mosayebi Mehran Rezaei Narges Hadian Fazlollah Zareie Kordshuli Fereshteh Meshkani 《Materials Research Bulletin》2012,47(9):2154-2160
A surfactant assisted co-precipitation method was employed for the low temperature synthesis of magnesium aluminate spinel with nanocrystalline size and high specific surface area. Pluronic P123 triblock copolymer and ammonia solution were used as surfactant and precipitation agent, respectively. The prepared samples were characterized by thermal gravimetric and differential thermal gravimetric analyses (TG/DTG), X-ray diffraction (XRD), N2 adsorption (BET) and transmission electron microscopy (TEM) techniques. The effects of several process parameters such as refluxing temperature, refluxing time, pH, P123 to metals mole ratio (P123/metals) and calcination temperature on the structural properties of the samples were investigated. The obtained results showed that, among the process parameters pH and refluxing temperature have a significant effect on the structural properties of samples. The results revealed that increase in pH from 9.5 to 11 and refluxing temperature from 40 °C to 80 °C increased the specific surface area of prepared samples in the range of 157–188 m2 g?1 and 162–184 m2 g?1, respectively. The XRD analysis showed the single-phase MgAl2O4 was formed at 700 °C. 相似文献
90.