A Study on the Ethnic Identity Machanisms of Scattered and Mixed Ethnic Groups

Mingxin Liu,Yonggang Li 인하대학교 다문화융합연구소 2020 다문화와 교육 Vol.5 No.1

Beicheng community of Qingzhou city is the only Manchu ghetto of Shandong province. On the basis of describing community’s historical change, this paper will analysis factors of the ethnic identity mechanism of Manchu in this scattered area, and show its difference from others.

Research on Injection Rate Allocation Fault Diagnosis in Integrated Separate Layer Water Injection Technology

Deli Jia,Xiaohan Pei,He Liu,Fuchao Sun,Mingxin Zhao 보안공학연구지원센터 2014 International Journal of Control and Automation Vol.7 No.12

Integrated separate layer water injection technology is an effective approach to reduce the workload of injection oilfield. The primary equipment which consists of flowmeter, motor and control value is placed underground for a long time. Injection rate allocation fault diagnosis is a problem with character of multiformity. The fault symptoms and reasons are random, and it is hard to differentiate them. Weighted fuzzy C-means clustering algorithm combining symptoms signals and fuzzy mathematics approach is used on the technology. The algorithm is based on fuzzy C-means clustering algorithm, and increase weight to each fault sample to reduce the impact of samples on fault classifications. Simulation and analysis illustrates that the algorithm is able to reflect the real structure of the sample data. And it improves the accuracy of fault classification.

Design and Implementation of the Phase-locked Amplifier

Mingxin Song,Fangfang Liu 보안공학연구지원센터 2015 International Journal of Signal Processing, Image Vol.8 No.5

The phase-locked amplifier with output stability can filter out the noise effectively and the weak signal will be extracted from the noise and be amplified. The signal processing is relatively simple, so it is an effective way to detect the weak signal. It uses the phase sensitive detector (Phase Sensitive Detection, PSD) technique to identify the test signal, which has same frequency with the reference signal, and eliminate the interference noise signal of different frequency, so as to accurately measure the size of the measured signal. In this paper, switching correlator is taken as a core part of lock-in amplifier with large dynamic range, strong anti-overload and no non-linear problems. Moreover, lock-in amplifier output signal amplitude has no impact from the amplitude of the reference .

Observation and Mechanism of Photo-isomerisation Induced Rapid Photo-degradation of Optical Nonlinearity in Guest-host Type Poled Polymer

Mingxin Ye,Lei Xu,Jieyun Yan,Liying Liu,Liyong Ji,Wencheng Wang 한국물리학회 2004 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.44 No.32

Photo-degradation of electric eld poled alpha0-cyano-40-nitro-4-N,N-dimethylaminostilbene (CNDS) doped polymer was investigated by second-harmonic generation (SHG), UV-Vis absorption and FTIR. We found that the addition of a cyano group makes CNDS much more easily photoisomerized, and thus destroys the molecular ordering in poled chromophore doped polymers. A comparison experiment revealed that the photo-isomerization of CNDS is even easier than that of a modal system of azobenzene, which shows that CNDS has potential applications, such as in optical switches.

Polyamide composite nanofiltration membrane modified by nanoporous TiO2 interlayer for enhanced water permeability

Mingzhu Chi,Pingyun Zheng,Mingxin Wei,Aimei Zhu,Lubin Zhong,Qiugen Zhang,Qinglin Liu 한국공업화학회 2022 Journal of Industrial and Engineering Chemistry Vol.115 No.-

The traditional polyamide composite nanofiltration membrane has high selectivity. However, low waterpermeability is an important problem to be solved. Herein, the conventional polyamide compositenanofiltration (TFC) membrane was modified with nanoporous TiO2 (nTiO2) interlayer throughvacuum-assisted strategy for enhanced water permeability. By tuning the nTiO2 nanoparticles loading,the nTiO2 modified TFC membrane with crumpled structure was fabricated. Besides, the thickness ofpolyamide layer was reduced due to the hydrophilicity and porosity of nTiO2. Because of the larger effectivefiltration area and thinner polyamide layer, the modified membrane had a permeability of12.8 L m2 h1 bar1 (increased by 20.8% than that of TFC membrane) and a rejection of 98.2% when filteringNa2SO4 aqueous solution. This work provided a solution for enhanced water permeability andextended the application of TiO2 in the modification of polyamide composite nanofiltration membrane.

Adaptive robust control of active magnetic bearings rigid rotor systems

Yuhao Xu,Xiaoyuan Wang,Mingxin Liu,Na Li,Tian Yu 전력전자학회 2023 JOURNAL OF POWER ELECTRONICS Vol.23 No.6

Aiming at the problems of diffi cult decoupling, complex controller models, and poor disturbance rejection capability caused by the inherent nonlinear and strong coupling characteristics of the active magnetic bearing (AMB), an adaptive H-infinity robust control (AHRC) method is proposed in the AMBs-rigid rotor system. The proposed method combines the active disturbance rejection control (ADRC) with the robust control to achieve stable operation of the AMBs-rigid rotor system under high-speed conditions. First, a four-degree-of-freedom (4-DOF) AMBs-rigid rotor model was established and transformed into a one-degree-of-freedom (1-DOF) model for the design of the robust controller, which weakens the coupling effect between each of the degrees of freedom (DOF). Then the multi-objective non-dominated sorting genetic algorithm II (NSGA-II) was used to fi nd the relative optimal weighting function value of the H-infinite robust control (HRC), which solved the difficulties in the design of the robust controller for known controlled system models. In addition, by combining the optimized H-infi nity robust controller with the original error feedback control rate in the ADRC, the proposed AHRC retains the strong robustness of the HRC and the decoupling capability of the ADRC, which improves the tracking performance and anti-disturbance performance of the controlled system. Simulation and experimental results verify the effectiveness of the proposed method.

Design and Development of a Single-photon Laser and Infrared Common Aperture Optical System

Wu Hongbo,Zhang Xin,Tan Shuanglong,Liu Mingxin,Wang Lingjie,Yan Lei,Liu Yang,Shi Guangwei 한국광학회 2022 Current Optics and Photonics Vol.6 No.2

A single-photon laser and mid-wave infrared (MWIR) common aperture optical system was designed and developed to detect and range a long-distance civil aviation aircraft. The secondary mirror of the Ritchey-Chretien (R-C) optical system was chosen as a dichroic lens to realize the design of a common aperture system for the laser and MWIR. Point spread function (PSF) ellipticity was introduced to evaluate the coupling efficiency of the laser receiving system. A small aperture stop and narrow filter were set in the secondary image plane and an afocal light path of the laser system, respectively, and the stray light suppression ability of the small aperture stop was verified by modeling and simulation. With high-precision manufacturing technology by single point diamond turning (SPDT) and a high-efficiency dichroic coating, the laser/MWIR common aperture optical system with a φ300 mm aluminum alloy mirror obtained images of buildings at a distance of 5 km with great quality. A civil aviation aircraft detection experiment was conducted. The results show that the common aperture system could detect and track long-distance civil aviation aircraft effectively, and the coverage was more than 450 km (signal-tonoise ratio = 6.3). It satisfied the application requirements for earlier warning and ranging of long-range targets in the area of aviation, aerospace and ground detection systems.

Quadratic‑type high step‑up DC–DC converter with continuous input current integrating coupled inductor and voltage multiplier for renewable energy applications

Fuwei Li,Jie He,Peng Luo,Haoyu Jiang,Mingxin Liu 전력전자학회 2023 JOURNAL OF POWER ELECTRONICS Vol.23 No.4

This paper presents a quadratic-type high step-up DC–DC converter for renewable energy applications with a continuousinput current. To reduce the number of components while increasing the gain, a quadratic boost converter and two multiplier cells are applied as the primary and secondary circuit with one coupled inductor connected. In addition, the clamp circuit shares its components with both the second boost stage and the voltage multiplier, which increases the power density. As a result, the leakage energy is recycled and the voltage stress can be suppressed. The operation principles and steady-state analyses including loss analysis of the proposed converter are addressed in detail. Compared with relevant existing topologies of quadratic converter, the proposed converter performs a higher voltage gain and a lower power switch stress. To validate the performance, a 200 W experimental prototype is constructed and tested with 20 V of input voltage and 400 V of output voltage, where the highest efficiency is 95.2% and the full-load efficiency is 93.7%. The performance under dynamic conditions is also verified. In the end, an improved topology based on the proposed converter is supplemented.

Facile preparation and characterization of tough poly(vinyl alcohol) organohydrogels with low friction and self-cleaning properties

Jia Yang,Jiajia Hao,Chen Tang,Yaxin Guo,Mingxin Guo,Zhipeng Li,Shuzheng Liu,Hui Yu,Gang Qin,Qiang Chen 한국공업화학회 2022 Journal of Industrial and Engineering Chemistry Vol.116 No.-

Although many hydrogels have been applied to wearable sensors, it is still challenging to simultaneouslyrealize hydrogels with optical transparency, superior mechanical properties, excellent sensing performance,and anti-freezing by using inexpensive raw materials and an easy preparation process. Herein,using ethylene glycol/H2O (EG/ H2O) as a solvent, poly(vinyl alcohol)/EG organohydrogel (PVA/EGOHG) was prepared by a simple heating and frozen-thawing method. Owing to the multifunctionalityof EG (i.e., physical cross-linker, anti-freezer and co-solvent), PVA/EG OHG demonstrated excellent integratedproperties, including high strength, high toughness, and anti-freezing performances. Besides, PVA/EG OHG also showed low friction, self-cleaning, and frost resistance properties. After the introduction ofLiCl, ionically conductive PVA/EG @LiCl organohydrogel was served as a self-cleaning strain sensor, whichcould be long-term stable to detect the motions of human under room and low temperatures. The studyprovides to further understanding of the organohydrogel, which will help us design next-generationhigh-performance organohydrogels.