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981.
982.
Fan Yin Edith Arámbula-Mercado David Newcomb 《International Journal of Pavement Engineering》2017,18(4):358-366
In the United States, mechanical foaming is the most popular method for producing warm mix asphalt, which is the latest technology implemented to reduce the production temperature and/or enhance the compactability of asphalt mixtures. Three commonly used commercially available laboratory foamers to produce asphalt foams include the Wirtgen WLB 10S (Wirtgen foamer), the InstroTek Accufoamer (InstroTek foamer) and the Pavement Technology Inc. Foamer (PTI foamer). Though these foamers have been widely used in research studies and construction practice, it is still unknown whether they produce asphalt foams with the same quality and quantity. In this study, asphalt foaming characteristics produced by these three laboratory foamers were measured using a non-contact test set-up consisting of a laser device and a digital camera, and compared in terms of instantaneous volume expansion, foam stability and surface area evolution of foam bubbles. Additionally, the workability, coatability and mechanical performance of foamed mixtures prepared using these same laboratory foamers were compared against the conventional hot mix asphalt (HMA). Test results indicated that foamed asphalts produced by the Wirtgen foamer had the largest volume expansion and greatest foam stability, followed by those produced by the InstroTek foamer and the PTI foamer. The optimum foaming water content (Wopt) was determined for each laboratory foamer based on the workability and coatability results of the corresponding foamed mixtures. In addition, the performance evaluation of the foamed mixtures produced at Wopt values indicated equivalent mixture stiffness but greater moisture susceptibility as compared to the conventional HMA. 相似文献
983.
984.
985.
Heather MacDonald Jacqueline Nelson George Galster Yin Paradies Kevin Dunn Rae Dufty-Jones 《Urban Policy and Research》2016,34(4):373-385
Investigating differential treatment in rental housing markets is important to ensure that renters are not discriminated against based on their personal characteristics. However, little Australian research has focused systematically on this question. This paper reports the results of a study that used paired tests to estimate the extent of differential treatment of Anglo, Indian, and Muslim Middle Eastern renters in the Sydney metropolitan housing market. We find statistically significant differences in treatment on several measures, including the likelihood an agent will offer an individual appointment, will provide additional information about other housing, will provide additional information about completing the application form, and will contact a prospective renter after an inspection. 相似文献
986.
Multimedia Tools and Applications - Dimensionality reduction techniques based on sparse representation have drawn great attentions recently and they are successfully applied to biometric... 相似文献
987.
Xu Y. J. Wang Z. J. Wu G. D. Yin J. P. Dong F. D. Jin Y. X. 《Strength of Materials》2019,51(4):616-623
Strength of Materials - The aftereffect damage efficiency of shaped charge jets formed with the conventional metal liner against light armor is quite low. The validity of the PTFE-copper powder... 相似文献
988.
Bao Zhuolan Li Wenwen Yin Pengzhen Chau Michael 《Information Systems and E-Business Management》2021,19(2):517-539
Information Systems and e-Business Management - Since online reviews have become an increasingly important information source for consumers to evaluate products during online shopping, many... 相似文献
989.
Yin Bao Lie Tang Matthew W. Breitzman Maria G. Salas Fernandez Patrick S. Schnable 《野外机器人技术杂志》2019,36(2):397-415
Sorghum (Sorghum bicolor) is known as a major feedstock for biofuel production. To improve its biomass yield through genetic research, manually measuring yield component traits (e.g. plant height, stem diameter, leaf angle, leaf area, leaf number, and panicle size) in the field is the current best practice. However, such laborious and time‐consuming tasks have become a bottleneck limiting experiment scale and data acquisition frequency. This paper presents a high‐throughput field‐based robotic phenotyping system which performed side‐view stereo imaging for dense sorghum plants with a wide range of plant heights throughout the growing season. Our study demonstrated the suitability of stereo vision for field‐based three‐dimensional plant phenotyping when recent advances in stereo matching algorithms were incorporated. A robust data processing pipeline was developed to quantify the variations or morphological traits in plant architecture, which included plot‐based plant height, plot‐based plant width, convex hull volume, plant surface area, and stem diameter (semiautomated). These image‐derived measurements were highly repeatable and showed high correlations with the in‐field manual measurements. Meanwhile, manually collecting the same traits required a large amount of manpower and time compared to the robotic system. The results demonstrated that the proposed system could be a promising tool for large‐scale field‐based high‐throughput plant phenotyping of bioenergy crops. 相似文献
990.