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1.
Silicon - In the present paper, investigation on wettability and contact angle measurement of twenty-one SAW fluxes for CaO-SiO2-TiO2 & Al2O3-CaO-SiO2 welding flux system at a temperature... 相似文献
2.
Wireless Personal Communications - During the development of wireless sensor networks for smart cities, deployment of nodes in three-dimensional space is important factor as data loss in such cases... 相似文献
3.
Koji Nishiguchi Rahul Bale Shigenobu Okazawa Makoto Tsubokura 《International journal for numerical methods in engineering》2019,117(2):221-248
We propose a full Eulerian incompressible solid-fluid interaction scheme capable of achieving high parallel efficiency and easily generating meshes for complex solid geometries. While good scalability of a full Eulerian solid-fluid interaction formulation has been reported by Sugiyama et al, their analysis was carried out using uniform Cartesian mesh and an artificial compressibility method. Typically, it is more challenging to achieve good scalability for hierarchical Cartesian meshes and a fully incompressible formulation. In addition, the conventional full Eulerian methods require a large computational cost to resolve complex solid geometries due to the usage of uniform Cartesian meshes. In an attempt to overcome the aforementioned issues, we employ the building-cube method, where the computational domain is divided into cubic regions called cubes. Each cube is divided at equal intervals, the same number of cubes is assigned to each core, and the spatial loop processing is executed for each cube. The numerical method is verified by computing five numerical examples. In the weak scaling test, the parallel efficiency at 32768 cores with 32 cores as a reference is 93.6%. In the strong scaling test, the parallel efficiency at 32768 cores with 128 cores as a reference is 70.2%. 相似文献
4.
通过有限元方法分析不同加工路线和条件对Al-4.5Cu-2Mg合金微观形变行为的影响。合金采用4种不同的加工技术和条件制备,分别为有或无细化剂的常规重力铸造、流变铸造和SIMA工艺。以合金的光学显微结构作为代表性体积元(RVEs),采用两种不同的边界条件模拟合金在单轴载荷作用下的变形行为,最后将模拟的应力-应变行为与实验结果进行比较。结果表明,微观结构形态对应力和应变分布及承载能力具有显著影响,共晶相比α(Al)相能承受更高的载荷,具有较薄且均匀分布的共晶网络结构的球状α(Al)相能提供更好的应力和应变分布。因此,SIMA加工合金比其他技术加工合金拥有更好的应力和应变分布。最后,将该合金的模拟屈服强度与实验进行验证,结果具有较好的一致性。 相似文献
5.
Rahul Sasidharan Pillai Matteo Frasnelli Vincenzo M. Sglavo 《Ceramics International》2018,44(2):1328-1333
The present work focuses on the fabrication of βTCP (β-tricalcium phosphate) and HA/βTCP (hydroxyapatite/β-tricalcium phosphate) composite coatings by plasma spraying. The starting powders were produced via solid-state method using 2 wt% MgO to stabilize βTCP phase. The synthesized powders were preliminarily granulated to be used by the plasma spray process. Coatings obtained on titanium substrates are uniform and well adherent but due to the high temperature and cooling rate typical for plasma spraying process, βTCP phase is almost totally transformed into the α allotrope. Thermal treatment at 800 °C allows the reconversion of the phase αTCP→ βTCP. It is therefore possible to produce coatings with tuneable dissolution properties by selecting the proper initial powder mixture and the specific thermal treatment. 相似文献
6.
Sandeep Kumar Singh Venkatesh Teja Banala Girish K. Gupta Ashwni Verma Rahul Shukla Vivek K. Pawar 《Drug development and industrial pharmacy》2015,41(11):1759-1768
The aim of this study was to fabricate docetaxel loaded nanocapsules (DTX-NCs) with a high payload using Layer-by-Layer (LbL) technique by successive coating with alternate layers of oppositely charged polyelectrolytes. Developed nanocapsules (NCs) were characterized in terms of morphology, particle size distribution, zeta potential (ζ-potential), entrapment efficiency and in vitro release. The morphological characteristics of the NCs were assessed using transmission electron microscopy (TEM) that revealed coating of polyelectrolytes around the surface of particles. The developed NCs successfully attained a submicron particle size while the ζ-potential of optimized NCs alternated between (+) 34.64?±?1.5 mV to (?) 33.25?±?2.1 mV with each coating step. The non-hemolytic potential of the NCs indicated the suitability of the developed formulation for intravenous administration. A comparative study indicated that the cytotoxicity of positively charged NCs (F4) was significant higher (p?0.05) rather than negative charged NCs (F3), plain drug (DTX) and marketed preparation (Taxotere®) when evaluated in vitro on MCF-7 cells. Furthermore, cell uptake studies evidenced a higher uptake of positive NCs (≥1.2 fold) in comparison to negative NCs. In conclusion, formulated NCs are an ideal vehicle for passive targeting of drugs to tumor cells that may result in improved efficacy and reduced toxicity of encapsulated drug moiety. 相似文献
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8.
Gupta Saurabh Tolani Varun Davidson James Levine Sergey Sukthankar Rahul Malik Jitendra 《International Journal of Computer Vision》2020,128(5):1311-1330
International Journal of Computer Vision - We introduce a neural architecture for navigation in novel environments. Our proposed architecture learns to map from first-person views and plans a... 相似文献
9.
Janardhan Rahul Kallada Shakil Saani Hassinen Marko Lu Wei Puttonen Jari Hostikka Simo 《Fire Technology》2022,58(4):2405-2440
Fire Technology - The feasibility of coupled computational fluid dynamics (CFD) and finite element (FE) simulations to aid the planning of fire intervention tactics and the effectiveness of... 相似文献
10.
Debojyoti Das Vaneet Bhatia Jayarethanam Pillai Aviral Kumar Tiwari 《Energy Sources, Part B: Economics, Planning, and Policy》2018,13(1):37-45
The authors revisit the relationship between US economic growth and crude oil prices considering Industrial Production Index and West Texas Intermediate crude oil spot prices as respective proxies for a period spanning over January 1986 to June 2017. To capture the asymmetric and time-varying relationship, the authors employ maximum overlap discrete wavelet transform (MODWT)-based quantile regression (QR) analysis. Interestingly, MODWT-based QR analysis provides evidence of supply-driven link between crude oil prices and economic growth in the short run. However, in the medium to long run a demand-driven link is dominant. In addition, the QR results without MODWT also advocate a demand-driven link. Overall, the result of this study adds a new dimension to the literature on the relationship between crude oil prices and economic growth by focusing upon the time-frequency varying business cycle fluctuations. 相似文献