Atomic insights into regulation of graphene sheets vertically attached to the FeF3·0.33H2O (002) surface by cation doping

Yanjun Pan,Yang Li,Jinda Luo,Xianyou Wang,Zhenhua Yang 한국물리학회 2019 Current Applied Physics Vol.19 No.10

Tightly and vertically attached graphene nanosheets (GNS) on the surface of FeF3·0.33H2O is extremely desirable to substantially accelerate electron transport, promoting rate capability of FeF3·0.33H2O. Based on present experiment and calculated surface energies, firstly, it has confirmed that F-terminated FeF3·0.33H2O (002) surface (FeF3·0.33H2O (002)-F) is more stable than FeF-terminated FeF3·0.33H2O (002) surface (FeF3·0.33H2O (002)- FeF) when μF varies from −1.92 eV to −0.30 eV. Then, by analysis of the interfacial structure and adsorption energies, it was proposed that GNS is incline to stand vertically on the FeF3·0.33H2O (002) surface via C–F bond. However, structural stability of FeF3·0.33H2O/GNS heterostructure is gradually weakened with increasing the number of GNS layers. Therefore, we further reported the important role of optimal doping element (Hf) in strengthening the vertical adsorption behavior of GNS on FeF3·0.33H2O (002) surface via thorough doping element search. And it turns out interfacial structure with hexa-coordinate polyhedron consists of Hf, F and O atoms is formed by strong hybridization of atomic orbits, which induces the interaction between FeF3·0.33H2O (002) surface and GNS to be profoundly strengthened.

Engineering geological zonation using interaction matrix of geological factors: An example from one section of Sichuan-Tibet Highway

Yanjun Shang,Hyeong-Dong Park,Zhifa Yang 한국지질과학협의회 2005 Geosciences Journal Vol.9 No.4

Synergistic Effect Between Cavitation Erosion and Corrosion for Friction Stir Processed NiAl Bronze in Artificial Seawater

Yang Li,Ying Lian,Yanjun Sun 대한금속·재료학회 2021 METALS AND MATERIALS International Vol.27 No.12

Herein, the friction stir processing (FSP) method was adopted to modify the microstructure of as-cast nickel aluminumbronze (NAB). The microhardness, cavitation erosion-corrosion mass loss, morphological damage and electrochemical testswere extensively examined. The results show that FSP can refine and uniform the microstructure of as-cast NAB alloy. FSPNAB alloy displays enhanced cavitation erosion resistance in distilled water and artificial seawater, as well as heightenedsensitive to corrosive media in artificial seawater. Quantitative analysis of the synergistic effect between cavitation erosionand corrosion shows that pure cavitation erosion components contributions largest for as-cast NAB. In contrast, FSP NABis greatly influenced by the synergistic effect component. The damaged surface shows that cavitation erosion mechanismsof as-cast NAB in distilled water and artificial seawater are similar, which is not the case for FSP NAB due to the synergisticeffect between cavitation erosion and corrosion.

Multi‑objective parameter optimization of multi‑shaft ring‑plate magnetic gear

Yanjun Ge,Dongning Liu,Junyue Yang,Daming Wang 전력전자학회 2023 JOURNAL OF POWER ELECTRONICS Vol.23 No.3

Parameter setting and optimization are key steps to improving the transmission performance of eccentric permanent magnetgear. Studying this step makes it possible to analyze the transmission relationship between the design parameters, and improve both the operation stability and the carrying capacity of eccentric permanent magnet gear. Taking multi-shaft ring-plate magnet gear (MRMG) as the research object, this paper analyzes the influence of actual structural parameters on torque performance through the comprehensive sensitivity method, and selects the parameters with the greatest influence as the main optimization parameters. Then using the BSO algorithm and the BP neural network, a prediction model of MRMG electromagnetic torque and torque density is established, the relationship between each of the parameters is analyzed, and the optimization parameter points are determined. By comparison with finite element simulations and experiments, the built model and its measured results and FEM analysis are shown to have good accuracy (error < 6%). Moreover, the model can quickly and accurately obtain optimization parameters, and greatly improve the transmission performance of the structure (the maximum torque increases by 15%, and the torque density increases by 36%).

Utilization of Completely Recycled Fine Aggregate for Preparation of Lightweight Concrete Partition Panels

Yibo Yang,Baixi Chen,Weizhen Zeng,Yanjun Li,Qiaohui Chen,Wenying Guo,Hengchang Wang,Yingqin Chen 한국콘크리트학회 2021 International Journal of Concrete Structures and M Vol.15 No.5

To reduce the cost of lightweight concrete (LWC) partition panels and to address recycling concrete waste, this work utilized completely recycled fine aggregate (CRFA) to replace the natural fine aggregate and ceramsite in the preparation of LWC and LWC partition panels. To this end, an autoclave-free curing process and an air-entraining agent were used to prepare the CRFA-LWC. The workability, compressive strength, drying shrinkage, and pore structure of the CRFA-LWC and the performance of the CRFA-LWC partition panels were then investigated. The results show that the optimal ratio of the CRFA to the cement is 2.2 for the lightweight concrete, and the optimal panel cross section is a rounded rectangular one. All the pores in the CRFA-LWC have a diameter of smaller than 0.17 mm, and the diameter of 89% of them is less than 0.05 mm. In order to satisfy the drying shrinkage requirements stipulated by Chinese code JC/T 169-2016, the CRFA-LWC should be cured for at least 10 days. The economic analysis concludes that the material cost of CRFA-LWC is 40% lower than that of the autoclaved ceramsite concrete. In addition, utilizing CRFA in lightweight concrete can ease the shortage of natural aggregate.

Transmission performance of planetary permanent magnet gear with few pole difference

Junyue Yang,Yanjun Ge 대한기계학회 2022 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.36 No.12

To study the transmission characteristics of a planetary permanent magnet gear with few pole difference, a two-dimensional analytical model based on air gap magnetic field is established, the solutions of Laplace and Poisson equations are obtained by separating variables, and the analytical expression of air gap magnetic induction intensity is developed through coordinate transformation and superposition principle. The electromagnetic torque formula is derived further. On the basis of theoretical analysis, a single-chip experimental prototype with a rated torque of 45 Nm is designed and manufactured. The correctness of the analytical model of air gap magnetic field is verified by air gap magnetic field detection experiment. The critical static torque and magnetic torque angle characteristics are determined by static torque loading experiment. The correctness of the transmission principle and magnetic field analysis is verified by dynamic loading experiment, and the dynamic torque fluctuation is analyzed.

The design of large packaging production line system based on Embedded Technology

Huan Yang,Qianqian Zhang,Chenghao Yuan,Hancheng zhao,Yanjun Xiao 보안공학연구지원센터 2016 International Journal of Multimedia and Ubiquitous Vol.11 No.8

Robot Manipulator Visual Servoing via Kalman Filter- Optimized Extreme Learning Machine and Fuzzy Logic

Zhiyu Zhou,Yanjun Hu,Jiangfei Ji,Yaming Wang,Zefei Zhu,Donghe Yang,Ji Chen 한국인터넷정보학회 2022 KSII Transactions on Internet and Information Syst Vol.16 No.8

Visual servoing (VS) based on the Kalman filter (KF) algorithm, as in the case of KF-based image-based visual servoing (IBVS) systems, suffers from three problems in uncalibrated environments: the perturbation noises of the robot system, error of noise statistics, and slow convergence. To solve these three problems, we use an IBVS based on KF, African vultures optimization algorithm enhanced extreme learning machine (AVOA-ELM), and fuzzy logic (FL) in this paper. Firstly, KF online estimation of the Jacobian matrix. We propose an AVOA-ELM error compensation model to compensate for the sub-optimal estimation of the KF to solve the problems of disturbance noises and noise statistics error. Next, an FL controller is designed for gain adaptation. This approach addresses the problem of the slow convergence of the IBVS system with the KF. Then, we propose a visual servoing scheme combining FL and KF-AVOA-ELM (FL-KF-AVOA-ELM). Finally, we verify the algorithm on the 6-DOF robotic manipulator PUMA 560. Compared with the existing methods, our algorithm can solve the three problems mentioned above without camera parameters, robot kinematics model, and target depth information. We also compared the proposed method with other KF-based IBVS methods under different disturbance noise environments. And the proposed method achieves the best results under the three evaluation metrics.

Rocaglamide-A Potentiates Osteoblast Differentiation by Inhibiting NF-κB Signaling

Li, Aiguo,Yang, Libin,Geng, Xiaolin,Peng, Xingmei,Lu, Tan,Deng, Yanjun,Dong, Yuzheng Korean Society for Molecular and Cellular Biology 2015 Molecules and cells Vol.38 No.11

Rheumatoid arthritis is a chronic inflammatory disease that leads to bone and cartilage erosion. The inhibition of osteoblast differentiation by the inflammatory factor TNF-${\alpha}$ is critical for the pathogenesis of rheumatoid arthritis. To modulate TNF-${\alpha}$ mediated inhibition of osteoblast differentiation is required to improve therapeutic efficacy of rheumatoid arthritis. Here, we explored the potential role of rocaglamide-A, a component of Aglaia plant, in osteoblast differentiation. Rocaglamide-A prevented TNF-${\alpha}$ mediated inhibition of osteoblast differentiation, and promoted osteoblast differentiation directly, in both C2C12 and primary mesenchymal stromal cells. Mechanistically, Rocaglamide-A inhibited the phosphorylation of NF-${\kappa}B$ component p65 protein and the accumulation of p65 in nucleus, which resulted in the diminished NF-${\kappa}B$ responsible transcriptional activity. Oppositely, overexpression of p65 reversed rocaglamide-A's protective effects on osteoblast differentiation. Collectively, rocaglamide-A protected and stimulated osteoblast differentiation via blocking NF-${\kappa}B$ pathway. It suggests that rocaglamide-A may be a good candidate to develop as therapeutic drug for rheumatoid arthritis associated bone loss diseases.

Characteristics and Causes of Extreme Rainfall Induced by Binary Tropical Cyclones over China

Mingyang Wang,Fumin Ren,Yanjun Xie,Guoping Li,Ming-Jen Yang,Tian Feng 한국기상학회 2021 Asia-Pacific Journal of Atmospheric Sciences Vol.57 No.2

Binary tropical cyclones (BTC) often bring disastrous rainfall to China. From the viewpoint of the extreme of the BTC maximum daily rainfall, the characteristics of BTC extreme rainfall (BTCER) during 1960–2018 are analyzed, using daily rainfall data; and some representative large-scale mean flows, in which the associated BTCs are embedded, are analyzed. Results show that the frequency of BTCER shows a decreasing trend [−0.49 (10 yr)−1] and is mainly distributed within the BTC heavy rainstorm interval (100 mm≤ BTCER <250 mm). BTCER occurs mostly from July to September with a peak in August. Three BTCER typical regions— Minbei, the Pearl River Delta (PRD), and Taiwan—are identified according to the clustering of stations with high BTCER frequency and large BTCER. A further analysis of the 850-hPa BTC composite horizontal wind and water vapor flux over the PRD region shows the existence of two water vapor transport channels, which transport water vapor to the western tropical cyclone. In the first of these channels, the transport takes place via the southwest monsoon, which accounts for 58% of the total moisture, and an easterly flow associated with eastern tropical cyclone accounts for the remaining 42%. Binary tropical cyclones (BTC) often bring disastrous rainfall to China. From the viewpoint of the extreme of the BTC maximum daily rainfall, the characteristics of BTC extreme rainfall (BTCER) during 1960–2018 are analyzed, using daily rainfall data; and some representative large-scale mean flows, in which the associated BTCs are embedded, are analyzed. Results show that the frequency of BTCER shows a decreasing trend [−0.49 (10 yr) −1 ] and is mainly distributed within the BTC heavy rainstorm interval (100 mm ≤ BTCER <250 mm). BTCER occurs mostly from July to September with a peak in August. Three BTCER typical regions— Minbei, the Pearl River Delta (PRD), and Taiwan—are identified according to the clustering of stations with high BTCER frequency and large BTCER. A further analysis of the 850-hPa BTC composite horizontal wind and water vapor flux over the PRD region shows the existence of two water vapor transport channels, which transport water vapor to the western tropical cyclone. In the first of these channels, the transport takes place via the southwest monsoon, which accounts for 58% of the total moisture, and an easterly flow associated with eastern tropical cyclone accounts for the remaining 42%.