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1.
《Ceramics International》2022,48(6):7748-7758
Micromechanics model, finite element (FE) simulation of microindentation and machine learning were deployed to predict the mechanical properties of Cu–Al2O3 nanocomposites. The micromechanical model was developed based on the rule of mixture and grain and grain boundary sizes evolution to predict the elastic modulus of the produced nanocomposites. Then, a FE model was developed to simulate the microindentation test. The input for the FE model was the elastic modulus that was computed using the micromechanics model and wide range of yield and tangent stresses values. Finally, the output load-displacement response from the FE model, the elastic modulus, the yield and tangent strengths used for the FE simulations, and the residual indentation depth were used to train the machine learning model (Random vector functional link network) for the prediction of the yield and tangent stresses of the produced nanocomposites. Cu–Al2O3 nanocomposites with different Al2O3 concentration were manufactured using insitu chemical method to validate the proposed model. After training the model, the microindentation experimental load-displacement curve for Cu–Al2O3 nanocomposites was fed to the machine learning model and the mechanical properties were obtained. The obtained mechanical properties were in very good agreement with the experimental ones achieving 0.99 coefficient of determination R2 for the yield strength. 相似文献
2.
基于网络零售平台与制造商的合作广告实践,运用Stackelberg博弈理论研究了平台交叉销售效应及合作广告引导作用对O2O供应链合作广告决策的影响,并通过数值算例对参与合作广告计划前后渠道成员的决策变量均衡结果和利润进行对比分析,研究发现平台交叉销售效应是影响网络零售平台合作广告计划制定和实施的关键因素,只有当其达到一定水平时,制造商才拥有参与网络零售平台合作广告计划的资格;在一定条件时,合作广告计划能够实现制造商和网络零售平台利润的提升;当平台交叉销售效应较大时,网络零售平台获得的利润大于制造商。 相似文献
3.
A new design method was proposed in this article to insert transmission zeros in the broadband filters. In this method, the coupling line was connected to a certain position on the resonator. And then the coupling strength was adjusted by the connecting position. The open end of the resonator was hung and then the cross‐coupling was introduced to realize transmission zeros. This coupling method could add an adjustable parameter to improve the freedom of design and convenient to insert the transmission zeros. To verify this method, a highly selective coupled‐line microstrip filter with two transmission zeros was designed, fabricated, and measured. The measured results were in good agreement with the simulated ones. The return and insertion losses of the broadband filter were better than 18 and 2 dB, respectively. The relative bandwidth of the filter (FBW) was more than 68%. The rectangular coefficient (30 dB:1 dB) was less than 1.21. 相似文献
4.
摘要:为明确影响活性焦烧结烟气脱硫的主要因素,通过模拟试验和生产数据统计分析探究脱硫塔自上至下脱硫率变化趋势和各运行参数对脱硫率的影响。模拟试验表明,循环使用后的活性焦孔隙结构更加发达,表面含氧官能团含量增加,进而其初期脱硫性能低于新鲜活性焦,后期优于新鲜活性焦。错流式脱硫塔自上至下脱硫率先后经历100%、快速降低、缓慢降低等过程。生产数据统计分析表明,脱硫率与SO2质量浓度、O2体积分数、H2O体积分数、NH3与NOx物质的量之比、解析温度呈正相关,与活性焦床温度、体积空速呈负相关。其中,SO2质量浓度、体积空速、活性焦床温度对脱硫率影响最大。运行参数之间存在多重共线性现象,烧结漏风率升高或空气补加量增加将引起诸多运行参数的变化,但总体上有利于脱硫率的提高。 相似文献
5.
The constrained groove pressing-cross route process was implemented on a commercially annealed AA5052 alloy at room temperature, with up to two passes (strain of ~4.64) along the rolling direction and transverse direction. The results showed the formation of an ultrafine-grained structure with an average sub-grain/cell size in the 300–500?nm range. The indentation hardness and tensile strength increased significantly, up to ~75 and 105%, respectively, and became more homogenous with a uniform and isotropic trend, as compared to the annealed alloy. According to the Hall–Petch and Taylor models used, grain refinement and increasing dislocation density were proposed as the main strengthening mechanisms. Fractographic studies revealed a ductile-fracture behaviour, with a dimpled structure proportional to the UFG structure. 相似文献
6.
Yaxin Chen Jiexiang Tong Jiahao Dong Jing Luo Xiaoya Liu 《Small (Weinheim an der Bergstrasse, Germany)》2019,15(13)
Fast and highly efficient enrichment and separation of glycoproteins is essential in many biological applications, but the lack of materials with high capture capacity, fast, and efficient enrichment/separation makes it a challenge. Here, a temperature‐responsive core cross‐linked star (CCS) polymer with boronate affinity is reported for fast and efficient enriching and separating of glycoproteins from biological samples. The temperature‐responsive CCS polymers containing boronic acid in its polymeric arms and poly(N‐isopropyl acrylamide) in its cross‐linked core are prepared using reversible addition‐fragmentation chain transfer polymerization via an “arm‐first” methodology. The soluble boronate polymeric arms of the CCS polymers provide a homogeneous reaction system and facilitate interactions between boronic acid and glycoproteins, which leads to a fast binding/desorption speed and high capture capacity. Maximum binding capacity of the prepared CCS polymer for horseradish peroxidase is determined to be 210 mg g?1, which can be achieved within 20 min. More interestingly, the temperature‐responsive CCS polymers exhibit rapid reversible thermal‐induced volume phase transition by increasing the temperature from 15 to 30 °C, resulting in a facile and convenient sample collection and recovery for the target glycoproteins. Finally, the temperature‐responsive CCS polymer is successfully applied to enrichment of low abundant glycoproteins. 相似文献
7.
Atsuki Yamaguchi Kazuki Fukui Yuki Fujiwara Shingo Tamaki Sachie Kusaka Fuminobu Sato 《Journal of Nuclear Science and Technology》2021,58(1):80-86
ABSTRACT It is important to perform neutron transport simulations with accurate nuclear data in the neutronics design of a fusion reactor. However, absolute values of large-angle scattering cross sections vary among nuclear data libraries even for well-examined nuclide of iron. Benchmark experiments focusing on large-angle scattering cross sections were thus performed to confirm the correctness of nuclear data libraries. The series benchmark experiments were performed at a DT neutron source facility, OKTAVIAN of Osaka University, Japan, by the unique experimental system established by the authors’ group, which can extract only the contribution of large-angle scattering reactions. This system consists of two shadow bars, target plate (iron), and neutron detector (niobium). Two types of shadow bars were used and four irradiations were conducted for one experiment, so that contribution of room-return neutrons was effectively removed and only large-angle scattering neutrons were extracted from the measured four Nb reaction rates. The obtained experimental results were compared with calculations for five nuclear data libraries including JENDL-4.0, JEFF.-3.3, FENDL-3.1, ENDF/B- VII, and recently released ENDF/B-VIII. It was found from the comparison that ENDF/B-VIII showed the best result, though ENDF/B-VII showed overestimation and others are in large underestimation at 14 MeV. 相似文献
8.
9.
重叠网络的社区发现是复杂网络研究中的重要问题。为了提高网络中重叠社区发现的时间效率,提出一种基于边图的线性流重叠社区发现算法LBSA。算法首先对于边图网络中的边进行随机的依次处理,完成节点的初步社区划分,再将其中重叠小社区合并到相似度最大的其他大社区中得到最终的社区。通过以上步骤,算法能够以接近线性的时间复杂度得到网络的重叠结构。从最终的实验结果来看,与其他算法相比,该算法能够在更短的时间有质量地发现网络中的重叠社区。 相似文献
10.
Stain density is an important parameter for optimising the quality of ultrastructural data obtained from several types of 3D electron microscopy techniques, including serial block-face electron microscopy (SBEM), and focused ion beam scanning electron microscopy (FIB-SEM). Here, we show how some straightforward measurements in the TEM can be used to determine the stain density based on a simple expression that we derive. Numbers of stain atoms per unit volume are determined from the measured ratio of the bright-field intensities from regions of the specimen that contain both pure embedding material and the embedded biological structures of interest. The determination only requires knowledge of the section thickness, which can either be estimated from the microtome setting, or from low-dose electron tomography, and the elastic scattering cross section for the heavy atoms used to stain the specimen. The method is tested on specimens of embedded blood platelets, brain tissue and liver tissue. 相似文献