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The Journal of Supercomputing - Dockless bike-sharing is more and more popular all over the world, which enables passengers to choose destinations more flexibly, so that the transfer radius between... 相似文献
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单传感器捕获的彩色-近红外(RGB-NIR)图像存在光谱干扰,从而导致重建出的标准彩色图像(RGB)图像与近红外(NIR)图像存在色彩失真以及细节信息模糊。针对这个问题提出一种基于深度学习的去马赛克方法,通过引入跳远连接与稠密连接解决了梯度消失和梯度弥散问题,使得网络更容易训练,并且提升了网络的拟合能力。首先,用浅层特征提取层提取了马赛克图像的像素相关性以及通道相关性等低级特征;然后,将得到的浅层特征图输入到连续多个的残差稠密块以提取专门针对去马赛克的高级语义特征;其次,为充分利用低级特征与高级特征,将多个残差稠密块提取到的特征进行组合;最后,通过全局跳远连接恢复最终的RGB-NIR图像。在深度学习框架Tensorflow上使用公共的图像与视觉表示组(IVRG)数据集、有植被的户外多光谱图像(OMSIV)数据集和森林(Forest)三个公开数据集进行实验。实验结果表明,所提方法优于基于多级自适应残差插值、基于卷积卷积和神经神经网络以及基于深度残差U型网络的主流的RGB-NIR图像去马赛克方法。 相似文献
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A biphenyl type liquid crystal epoxy (LCE) monomer 4,4′-di(2,3-epoxyhexyloxy)biphenyl (LCBP4) containing flexible chain was synthesized and the curing behavior was investigated using 4,4′-diaminodiphenylmethane (DDM) as the curing agent. The effect of curing condition on the formation of the liquid crystalline phase was examined. The cured samples show good mechanical properties and thermal stabilities. Moreover, the relationship between thermal conductivity and structure of liquid crystalline domain was also discussed. The samples show high thermal conductivity up to 0.28–0.31 W/(m*K), which is 1.5 times as high as that of conventional epoxy systems. In addition, thermal conductive filler, Al2O3, was introduced into LCBP4/DDM to obtain higher thermal conductive composites. When the content of Al2O3 was 80 wt%, the thermal conductivity of the composite reached to 1.86 W/(m*K), while that of diglycidyl ether of bisphenol A (Bis-A) epoxy resin/DDM/Al2O3 was 1.15 W/(m*K). Compared with Bis-A epoxy resin, the formation of liquid crystal domains in the cured LCE resin enhanced the thermal conductivity synergistically with the presence of Al2O3. Furthermore, the introduction of Al2O3 also slightly increased the thermal stabilities of the cured LCE. 相似文献
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Ke Gan Yanjiao Gai Yali Wang Jie Cui Yuju Lu Xiaoyan Zhang Jingjing Liu Jie Xu Jinlong Yang 《International Journal of Applied Ceramic Technology》2020,17(1):274-284
A direct coagulation casting method for silicon carbide ceramic suspension using dispersant crosslink reaction is reported. Polymer electrolyte (polyethyleneimine, PEI) was used as dispersant to prepare silicon carbide suspension. Common food additives (carboxymethyl cellulose, CMC) were used to coagulate the electrosteric stabilized silicon carbide suspension. There was a well disperse silicon carbide suspension with 0.2 wt% PEI at pH = 5-6. Influence of coagulant on viscosity and zeta potential of the silicon carbide suspension was investigated. It indicates that the high solid loading silicon carbide suspension can be destabilized and coagulated at elevated temperature. It can be attribute to the gradual decrease of electrosteric force due to the crosslink reaction between PEI and CMC. Silicon carbide wet green body with compressive strength of 1.99 MPa could be demolded at 70°C which is higher than that prepared by traditional DCC and dispersant reaction method for nonoxide ceramics. Dense silicon carbide ceramics with relative density above 98.8% and 99.3% had been prepared by liquid phase pressureless and hot pressed sintering, respectively. 相似文献
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Multicellular tumor spheroid models (MCTS) are often coined as 3D in vitro models that can mimic the microenvironment of tissues. MCTS have gained increasing interest in the nano‐biotechnology field as they can provide easily accessible information on the performance of nanoparticles without using animal models. Considering that many countries have put restrictions on animals testing, which will only tighten in the future as seen by the recent developments in the Netherlands, 3D models will become an even more valuable tool. Here, an overview on MCTS is provided, focusing on their use in cancer research as most nanoparticles are tested in MCTS for treatment of primary tumors. Thereafter, various types of nanoparticles—from self‐assembled block copolymers to inorganic nanoparticles, are discussed. A range of physicochemical parameters including the size, shape, surface chemistry, ligands attachment, stability, and stiffness are found to influence nanoparticles in MCTS. Some of these studies are complemented by animal studies confirming that lessons from MCTS can in part predict the behaviour in vivo. In summary, MCTS are suitable models to gain additional information on nanoparticles. While not being able to replace in vivo studies, they can bridge the gap between traditional 2D in vitro studies and in vivo models. 相似文献