Tongji University

About: Tongji University is a education organization based out in Shanghai, China. It is known for research contribution in the topics: Computer science & Population. The organization has 76116 authors who have published 81176 publications receiving 1248911 citations. The organization is also known as: Tongji & Tóngjì Dàxué.

The utilization of eco-friendly recycled powder from concrete and brick waste in new concrete: A critical review

Abstract: Recycled powder (RP) is the main by-product in the reclamation of construction and demolition (CD in addition, improvement methods and a benefit evaluation of RP concrete are further introduced. Based on statistical data that describe the activity index of RP and the compressive strength of RP concrete, the median diameter and replacement ratio of RP in concrete preparation should be below 30 μm and 30%, respectively. The use of RP improves the durability of concrete when the RP fineness is superior to the cement fineness. Increasing the RP fineness is an effective approach to improving the properties of RP concrete, and a CO2-curing treatment of RCP is an eco-friendly modification method. Furthermore, the use of RP in concrete has good economic and environmental benefits. Therefore, one expects that this review helps the further use of RP in concrete.

Substrate coupling suppresses size dependence of thermal conductivity in supported graphene

Abstract: Thermal conductivity κ of both suspended and supported graphene has been studied by using molecular dynamics simulations An obvious length dependence is observed in κ of suspended single-layer graphene (SLG), while κ of supported SLG is insensitive to the length The simulation result of room temperature κ of supported SLG is in good agreement with the experimental value In contrast to the decrease in κ induced by inter-layer interaction in suspended few-layer graphene (FLG), κ of supported FLG is found to increase rapidly with the layer thickness, reaching about 90% of that of bulk graphite at six layers, and eventually saturates at the thickness of 134 nm More interestingly, unlike the remarkable substrate dependent κ in SLG, the effect of substrate on thermal transport is much weaker in FLG The underlying physics is investigated and presented

Revisiting Perspective Information for Efficient Crowd Counting

Abstract: Crowd counting is the task of estimating people numbers in crowd images. Modern crowd counting methods employ deep neural networks to estimate crowd counts via crowd density regressions. A major challenge of this task lies in the perspective distortion, which results in drastic person scale change in an image. Density regression on the small person area is in general very hard. In this work, we propose a perspective-aware convolutional neural network (PACNN) for efficient crowd counting, which integrates the perspective information into density regression to provide additional knowledge of the person scale change in an image. Ground truth perspective maps are firstly generated for training; PACNN is then specifically designed to predict multi-scale perspective maps and encode them as perspective-aware weighting layers in the network to adaptively combine the outputs of multi-scale density maps. The weights are learned at every pixel of the maps such that the final density combination is robust to the perspective distortion. We conduct extensive experiments on the ShanghaiTech, WorldExpo’10, UCF_CC_50, and UCSD datasets, and demonstrate the effectiveness and efficiency of PACNN over the state-of-the-art.

Fabrication of drug‐loaded electrospun aligned fibrous threads for suture applications

Abstract: In this work, drug-loaded fibers and threads were successfully fabricated by combining electrospinning with aligned fibers collection Two different electrospinning processes, that is, blend and coaxial electrospinning, to incorporate a model drug tetracycline hydrochloride (TCH) into poly(L-lactic acid) (PLLA) fibers have been used and compared with each other The resulting composite ultrafine fibers and threads were characterized through scanning electron microscopy, transmission electron microscopy, Fourier transform infrared spectroscopy, X-ray diffraction, differential scanning calorimetry, and tensile testing It has been shown that average diameters of the fibers made from the same polymer concentration depended on the processing method The blend TCH/PLLA fibers showed the smallest fiber diameter, whereas neat PLLA fibers and core-shell TCH-PLLA fibers showed a larger proximal average diameter Higher rotating speed of a wheel collector is helpful for obtaining better-aligned fibers Both the polymer and the drug in the electrospun fibers have poor crystalline property In vitro release study indicated that threads made from the core-shell fibers could suppress the initial burst release and provide a sustained drug release useful for the release of growth factor or other therapeutic drugs On the other hand, the threads from the blend fibers produced a large initial burst release that may be used to prevent bacteria infection A combination of these results suggests that electrospinning technique provides a novel way to fabricate medical agents-loaded fibrous threads for tissue suturing and tissue regeneration applications