A Deflectable Switched Reluctance Motor/Generator for Wave Energy Conversion and Underwater Propulsion Systems

Gao Shihao,Wang Qunjing,Li Guoli,Qian Zhe,Zhou Sili,Li Zheng 대한전기학회 2021 Journal of Electrical Engineering & Technology Vol.16 No.6

This paper proposes a defl ectable switched reluctance motor/generator, which can be used in wave energy conversion and underwater propulsion systems. When an underwater vehicle stops working, the ocean current drives the turbine blades connected to the motor to rotate, and the rotating turbine blades drive the defl ectable generator shaft to generate electricity. The defl ectable motor can complete multi-degree-of-freedom motion, so it can receive ocean current energy in multiple directions, thereby improving energy extraction effi ciency. When the underwater vehicle starts to work, the defl ectable motor can freely adjust the course of the vehicle, so that the vehicle can yaw freely under water. The fi nite element method is used to analyze the air gap fl ux density during rotation and defl ection. The relationship between the fl ux, torque and current of a single coil under diff erent rotor positions is obtained, and then the output current and voltage of the defl ectable generator are obtained. Finally, a prototype was made for experimental verifi cation.

Room-temperature 2 μm luminescence from Tm doped silicon light emitting diodes and SOI substrates

Zhou Shihao,Milosavljević M.,Xia Xiaohong,Gao Yun,Lourenço M.A.,Homewood K.P. 한국물리학회 2021 Current Applied Physics Vol.31 No.-

Room temperature electroluminescence in the eye safe region of the spectrum over the range 1.7–2.1 μm is demonstrated from a thulium doped silicon diode. The same room temperature photoluminescence can be attained on a silicon-on-insulator substrate. The emission lines are from the first excited to ground state of the Tm3+ ion, 3F4→3H6. A detailed study has been made to establish the optimum implant and processing conditions for efficient room temperature luminescence. The importance of the correct placement of the thulium ions with respect to the depletion region edge and dislocation loops formed upon boron implantation has been established. Tm3+ has been demonstrated to lase in other systems and is the basis of widely applied, commercial, optically pumped 2 μm lasers. The demonstration of electroluminescence in silicon and luminescence on an SOI platform are necessary prerequisites for the potential development of Tm injection lasers and optical amplifiers.

Evolutionary Neural Network based on Quantum Elephant Herding Algorithm for Modulation Recognition in Impulse Noise

( Hongyuan Gao ),( Shihao Wang ),( Yumeng Su ),( Helin Sun ),( Zhiwei Zhang ) 한국인터넷정보학회 2021 KSII Transactions on Internet and Information Syst Vol.15 No.7

In this paper, we proposed a novel modulation recognition method based on quantum elephant herding algorithm (QEHA) evolving neural network under impulse noise environment. We use the adaptive weight myriad filter to preprocess the received digital modulation signals which passing through the impulsive noise channel, and then the instantaneous characteristics and high order cumulant features of digital modulation signals are extracted as classification feature set, finally, the BP neural network (BPNN) model as a classifier for automatic digital modulation recognition. Besides, based on the elephant herding optimization (EHO) algorithm and quantum computing mechanism, we design a quantum elephant herding algorithm (QEHA) to optimize the initial thresholds and weights of the BPNN, which solves the problem that traditional BPNN is easy into local minimum values and poor robustness. The experimental results prove that the adaptive weight myriad filter we used can remove the impulsive noise effectively, and the proposed QEHA-BPNN classifier has better recognition performance than other conventional pattern recognition classifiers. Compared with other global optimization algorithms, the QEHA designed in this paper has a faster convergence speed and higher convergence accuracy. Furthermore, the effect of symbol shape has been considered, which can satisfy the need for engineering.

Synthesis and characterization of curcumin-loaded pH/reduction dual-responsive folic acid modified carboxymethyl cellulose-based microcapsules for targeted drug delivery

Qingye Meng,Shuangling Zhong,Shihao He,Yan Gao,Xuejun Cui 한국공업화학회 2022 Journal of Industrial and Engineering Chemistry Vol.105 No.-

In the present study, an eco-friendly, biodegradable, biocompatible, non-immunogenic, non-toxicpolysaccharide, carboxymethyl cellulose (CMC), derivatived from renewable biomass cellulose, was usedfor designing and fabrication a folic acid modified pH and reduction dual-responsive carboxymethylcellulose-based microcapsules (FA-PRCMCs). The curcumin (CUR)-loaded microcapsules (FAPRCMCs@CUR) were prepared via a quick, efficient and environment-friendly sonochemical method,and were employed for the targeted delivery and pH/reduction dual-stimuli-responsive release of CUR. The excess CUR and ethyl acetate phases could be recycled and reused after preparation of FAPRCMCs@CUR to avoid wasting resources and polluting the environment. The obtained FA-PRCMCsshowed good biocompatibility and targeting in anti-tumor evaluation and endocytosis evaluationin vitro. FA-PRCMCs could effectively reduce the unnecessary damage to normal cells by chemotherapydrugs, and improve the utilization of chemotherapy drugs to reduce therapy costs. FA-PRCMCs could beused as smart targeted delivery vectors and have great clinical application potential.

Underwater superoleophobic copper mesh coated with block nano protrusion hierarchical structure for efficient oil/water separation

Xinyu Qi,Zhuwei Gao,Chengxin Li,Shihao Wang,Xin Zou,Lan He,Zhongxin Liu 한국공업화학회 2023 Journal of Industrial and Engineering Chemistry Vol.119 No.-

Compared with monolayer nanosheet membranes, multilayer nanosheet membranes have low energyconsumption and can be mass-produced for industrial applications. Herein, a multi-layer nanostructuredmembrane, nickel-doped brochantite/Cu(OH)2 nano protrusion structure coated copper meshes(NBCPCMs), were successfully prepared. Firstly, the surface of the copper mesh was etched by chemicaloxidation to form a disordered copper hydroxide nanosheet layer. Secondly, the etched copper mesh surfacewas coated with nickel-controlled brochantite block-like protrusions by hydrothermal synthesismethod, and nickel-doped brochantite/Cu(OH)2 nanosheets were generated by high pressure. The resultsshowed that NBCPCM-4 had excellent hydrophilic/underwater superoleophobicity, the oil–water separationefficiency of immiscible cyclohexane/water mixture was the highest, about 98.54%, and still had avery high flux (>60 (kL/(hm2))) after multiple cycles of separation. In addition to ultra-high separationefficiency, NBCPCM-4 also had super durability. The copper mesh maintained good underwater superoleophobicityin different aqueous solutions. Therefore, NBCPCM-4 is a potential high-efficiency and sustainableoil–water separation membrane material. It is expected that the developed technology is usefulfor sea transportation and marine environment management, along with other industries.

Research Progress of Hydrostatic Bearing and Hydrostatic-Hydrodynamic Hybrid Bearing in High-End Computer Numerical Control Machine Equipment

Xiaodong Yu,Weicheng Gao,Yanan Feng,Guangqiang Shi,Shihao Li,Minmin Chen,Ruiming Zhang,Junfeng Wang,Wentao Jia,Jianhua Jiao,Ruichun Dai 한국정밀공학회 2023 International Journal of Precision Engineering and Vol.24 No.6

Hydrostatic bearing has the advantages of wide speed range, large bearing capacity, high precision and stability. Hydrostatic-hydrodynamic hybrid bearing can make up for the lack of stiffness of hydrostatic bearing and prevent tribological failure under the condition of high speed and heavy load. Therefore, hydrostatic bearing and hydrostatic-hydrodynamic hybrid bearing have become important bearing parts of high-end computer numerical control (CNC) machine equipment. The research on hydrostatic and hydrostatic-hydrodynamic open a new way for precision improvement of high-end CNC machine equipment. This paper reviews research progress of hydrostatic linear guideway, hydrostatic rest and ram, hydrostatic thrust bearing, hydrostatic-hydrodynamic thrust bearing and hydrostatic-hydrodynamic spindle of high-end CNC machine equipment, and discusses the influence of structure and working parameters on lubrication performance, accuracy and stability of bearing parts. Finally, the future research direction in hydrostatic bearing and hydrostatic-hydrodynamic hybrid bearing are suggested. This review provides a theoretical basis for design and development of high-end CNC machine equipment in the future.

Toward Understanding the Adsorption And Inhibition Mechanism of Cu‑MBTA Passivation Film on Copper Surface: A Combined Experimental and DFT Investigation

Mengrui Liu,Da Yin,Baimei Tan,Fan Yang,Xiaoqin Sun,Pengcheng Gao,Shihao Zhang,Yazhen Wang 대한금속·재료학회 2021 ELECTRONIC MATERIALS LETTERS Vol.17 No.1

The adsorption and passivation reactions of 5-methyl benzotriazole (MBTA) with different copper samples (as received, citricacid treated and citric acid and KIO4treated) were studied. The experiments were characterized by contact angle measurement,potentiodynamic polarization curve, electrochemical impedance spectroscopy and X-ray photoelectron spectroscopy. The results showed that the adsorption behavior of MBTA on different treated surfaces was different and MBTA was preferentiallyadsorbed on the surface of citric acid treated copper. Based on the density functional theory, quantum chemicaldescriptors such as the frontier molecular orbital energies EHOMO,ELUMOand the energy gap between them, molecularelectrostatic potential, and Fukui function had been calculated and discussed. The adsorption mechanism of MBTA andcopper surface was further revealed, which had positive significance for the corrosion inhibition of copper surface in copperinterconnection CMP.