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1.
摘 要:核心网业务模型的建立是5G网络容量规划和网络建设的基础,通过现有方法得到的理论业务模型是静态不可变的且与实际网络存在偏离。为了克服现有5G核心网业务模型与现网模型适配性较差以及规划设备无法满足用户实际业务需求的问题,提出了一种长短期记忆(long short-term memory,LSTM)网络与卷积LSTM (convolution LSTM,ConvLSTM)网络双通道融合的 5G 核心网业务模型预测方法。该方法基于人工智能(artificial intelligence,AI)技术以实现高质量的核心网业务模型的智能预测,形成数据反馈闭环,实现网络自优化调整,助力网络智能化建设。  相似文献   
2.
ZnO rice like nonarchitects are grafted on the graphene carbon core via a rapid microwave synthesis route. The prepared grafted systems are characterized via XRD, SEM, RAMAN, and XPS to examined the structural and morphological parameters. Zinc oxide grafted graphene sheets (ZnO-G) are further doped in β-phase of polyvinylidene fluoride (PVDF) to prepare the polymer nanocomposites (PNCs) via mixed solvent approach (THF/DMF). β-phase confirmation of PVDF PNCs is done by FTIR studies. It is observed that ZnO-G filler enhances the β-phase content in the PNCs. Non-doped PVDF and PNCs are further studied for rheological behavior under the shear rate of 1–100 s−1. Doping of ZnO-G dopant to the PVDF matrix changes its discontinuous shear thickening (DST) behavior to continues shear thickening behavior (CST). Hydrocluster formation and their interaction with the dopant could be the reason for this striking DST to CST behavioral change. Strain amplitude sweep (10−3% -10%) oscillatory test reveals that the PNCs shows extended linear viscoelastic region with high elastic modulus and lower viscous modulus. Effective shear thickening behavior and strong elastic strength of these PNCs present their candidature for various fields including mechanical and soft body armor applications.  相似文献   
3.
In this work, a new type of FeSi/FeNi soft magnetic powder core (SMPC) was successfully fabricated by coating FeNi nanoparticles on the surface of FeSi micrometer powder. The effects of different contents of FeNi nanoparticles on the micromorphology, internal structures, and soft magnetic properties of SMPCs were studied. The results show that FeNi nanoparticles adhere to the surface of FeSi powder, which can effectively fill the air gap between FeSi powder and is beneficial to the compaction of the powder cores during the pressing process. Thus, the density of the SMPCs is increased. Compared to FeSi SMPCs, the comprehensive soft magnetic properties of FeSi/FeNi SMPCs have been greatly improved. When adding 15 wt% FeNi nanoparticles, the SMPCs exhibit excellent magnetic properties with high effective permeability (increased by 43.8 %) and low core loss (decreased by 22.1 %). The high performance FeSi/FeNi SMPCs prepared in this work are expected to be widely used in power choke coils, uninterruptible power supplies, and boosts and inverter inductors.  相似文献   
4.
《Ceramics International》2022,48(6):7593-7604
The ceramic core, produced by hot injection molding, is one of the critical components for manufacturing high-performance aircraft engine turbine blades. However, the injection molding process will cause defects such as burrs and flashes in the fine structure of the formed ceramic core. Manual trimming is necessary, but the trimming quality is poor, and the yield is low. In this paper, the online trimming method of ceramic cores is studied. Based on the orthogonal experiment method, the optimal laser parameters for processing the ceramic core's porous multi-scale particle structure material were obtained. Further, the problems of the match head and tail phenomenon and dimensional accuracy improvement in trimming ceramic cores have been studied. A path optimisation method is proposed to improve the quality and accuracy of the trimming profile effectively. Finally, the overall process flow of ceramic core trimming is elaborated, and experimental verification is given. The results show that the ceramic core online trimming method proposed in this paper has advantages of high precision and high yield compared with the manual method, which will have substantial potential application value in the aviation field.  相似文献   
5.
基于神经网络和遗传算法的锭子弹性管性能优化   总被引:1,自引:0,他引:1  
为得到减振弹性管对下锭胆的支承弹性和锭子高速运动下的稳定性等性能的最优匹配效率,依据减振弹性管的等效抗弯刚度及底部等效刚度系数公式,利用MatLab数值分析软件构建弹性管抗弯刚度和底部挠度数学模型。首先,结合Isight优化软件基于径向基神经网络构建其近似模型,且使精度达到可接受水平,并以模型的关键结构参数弹性模量、螺距、槽宽、壁厚为设计变量,结合遗传算法对弹性管抗弯刚度和底部挠度进行多目标优化设计,得到Pareto最优解集和Pareto前沿图,确定出减振弹性管结构工艺参数的优化方案。通过对优化数据进行分析发现,该方案在保证减振弹性管弹性的同时,其底部振幅明显减弱。  相似文献   
6.
Engineering novel Sn-based bimetallic materials could provide intriguing catalytic properties to boost the electrochemical CO2 reduction. Herein, the first synthesis of homogeneous Sn1−xBix alloy nanoparticles (x up to 0.20) with native Bi-doped amorphous SnOx shells for efficient CO2 reduction is reported. The Bi-SnOx nanoshells boost the production of formate with high Faradaic efficiencies (>90%) over a wide potential window (−0.67 to −0.92 V vs RHE) with low overpotentials, outperforming current tin oxide catalysts. The state-of-the-art Bi-SnOx nanoshells derived from Sn0.80Bi0.20 alloy nanoparticles exhibit a great partial current density of 74.6 mA cm−2 and high Faradaic efficiency of 95.8%. The detailed electrocatalytic analyses and corresponding density functional theory calculations simultaneously reveal that the incorporation of Bi atoms into Sn species facilitates formate production by suppressing the formation of H2 and CO.  相似文献   
7.
传统的堆芯功率PID控制器是基于单一功率水平处的堆芯局部模型设计的,难以准确描述整个堆芯功率水平范围的控制。因此,本文基于5个不同功率水平下的传递函数模型,通过三角隶属度函数加权,建立堆芯模糊多模型,并依据该模型设计堆芯功率模糊PID控制。以TMI型压水堆堆芯为对象,开展不同初始功率水平下的堆芯功率跟踪、堆芯进口温度扰动的控制仿真。结果表明,基于模糊多模型设计的堆芯功率模糊PID控制器可实现对堆芯功率的良好控制。  相似文献   
8.
通过对42CrMo4风机主轴结构尺寸、性能要求、材质特点等方面进行分析,对原有锻后热处理工艺进行优化,制定出既能达到锻后热处理效果又经济节能的工艺参数。  相似文献   
9.
Among various drug-delivery systems, core-shell nanoparticles have many advantages. Inspired by nature, biomimetic synthesis has emerged as a new strategy for making core-shell nanoparticles in recent years. Biomimetic mineralization is the process by which living organisms produce minerals based on biomolecule templating that leads to the formation of hierarchically structured organic–inorganic materials. In this minireview, we mainly focus on the synthesis of core-shell nanoparticle drug-delivery systems by biomimetic mineralization. We review various biomimetic mineralization methods for fabricating core-shell nanoparticles including silica-based, calcium-based and other nanoparticles, and their applications in drug delivery. We also summarize strategies for drug loading in the biomolecule-mineralized core-shell NPs. Current challenges and future directions are also discussed.  相似文献   
10.
分析了乐滩灌区工程北干渠溯河隧洞段长约1.06 km穿合山煤矿采空区的地质情况.借鉴高速公路煤矿采空区的成功处理经验,通过科学分析,对采空区变形和区域内覆岩的稳定性做了评价,论述了输水线路穿采空区段采取全充填压力注浆法的工程处理方法.  相似文献   
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