Articles in press have been peer-reviewed and accepted, which are not yet assigned to volumes /issues, but are citable by Digital Object Identifier (DOI).
Display Method:
Display Method:
cover
2019, 33(4).  
Abstract(0) PDF 2607KB(0)
Abstract:
contnets
2019, 33(4).  
Abstract(0) FullText HTML(0) PDF 467KB(1)
Abstract:
Planar Motor Driven by Cross Structured anUltrasonic Transducer
Min-jie LE, Hong-lin HE, Yu-fan LONG, Zhe-yi WANG
2019, 33(4): 1-6, 109.   doi: 10.3969/j.issn.1001-4926.2019.04.001
Abstract(0) FullText HTML(0) PDF 1146KB(0)
Abstract:
Due to the output amplitude of the planar motor driven by an X-shaped piezoelectric vibrator was fairly smaller, a planar motor resonantly driven by a cross-structure stator was proposed. It selected all the in-plane bending vibration mode of the transverse bar, the in-plane bending mode of longitudinal bar, and the out-of-plane bending mode of the stator as working modes. By coupling out-of-plane bending mode with transverse bar’s in-plane bending mode and the longitudinal bar’s in-plane bending mode, the elliptical trajectories along the yoz and xoz planes respectively were generated in the driving feet, so that the slider could be pushed to move along x, y directions. The working principle of the motor is explained. According to the requirement of working modal frequency consistency, the size of stator is optimized to be 25.5 mm × 5 mm × 5.9 mm.A FEM model for the stator was established, with which the optimal driving frequency was calculated to be 24 650 Hz, Transient analysis was also carried out which exhibited that the driving feet vibration amplitude along x, y, and z directions could reach 3.1, 6.2 and 4.3 μm when 250 V voltage was applied. It was shown that the stator hadproduced greater power and speed.
FBG Vibration Sensing System Based on F-P Cavity Tunable Filter
Zao-biao SONG, Qi XIONG, Sheng-peng WAN, Peng JIA
2019, 33(4): 7-11, 17.   doi: 10.3969/j.issn.1001-4926.2019.04.002
Abstract(0) FullText HTML(0) PDF 871KB(0)
Abstract:
In this paper, the narrow line width light source is generated by F-P cavity tunable filter and broadband light source. By adjusting F-P cavity filter, narrow line width light source works at the edge of the reflection spectrum of Fiber Bragg Grating (FBG), thus realizing the vibration sensing system based on FBG. The driving voltage of F-P cavity tunable filter is generated by STM32, the output signal of Photo detector (PD) is collected by DAQ, and the time-domain waveform and spectrum of vibration signal are displayed by PC software based on LabVIEW. By studying the dynamic drift characteristics of F-P cavity tunable filter, it is found that pre-voltage can weaken the influence of dynamic drift on system performance. Finally, by comparing the test results of the commercial electrical vibration detection system with the experimental system proposed in this paper, the results show relative error of the experimental system proposed in this paper is less than 3% when the vibration frequency is less than 100 Hz.
First-principles Study on Structural and Thermodynamics Properties of Li3Si2 Alloy
Bo XU, Jing SHI, Bao-zhen SUN
2019, 33(4): 12-17.   doi: 10.3969/j.issn.1001-4926.2019.04.003
Abstract(0) FullText HTML(0) PDF 943KB(0)
Abstract:
Using the First-principles method based on density functional theory, we have studied the electronic structure and the phonon dispersion of Li-Si alloy (Li3Si2). The results show that Li3Si2 presents the metallic electronic structure. The thermodynamic properties were studies by using the quasi-harmonic Debye model. We found that the thermal expansion coefficient increases almost exponentially for the temperature from 0 K up to 300 K. However, above 300 K, this trend begins to slow down. This indicates that the thermal expansion coefficient of the crystal is less affected at high temperature. Therefore, Li3Si2 has a good structural stability at high temperature. Our results provide a theoretical reference for the design of stable Si-based anode materials.
Correlation Analysis between Double-plateau Ground Motion Intensity Index and Frame Structure Response Displacement
Zhuo QIU, Ju-fang ZHONG, Hua-cong LI
2019, 33(4): 18-25, 38.   doi: 10.3969/j.issn.1001-4926.2019.04.004
Abstract(0) FullText HTML(0) PDF 968KB(0)
Abstract:
The seismic damage caused by the double-plateau ground motion of the large earthquake with multi-fault rupture is much more serious than that of the single-plateau ground motion. At present, it is not clear what kind of intensity index is used to better describe the characteristics of the double-plateau ground motion. Based on the record of the 5.12 Wenchuan earth quake with obvious double-plateau characteristics, the correlation between the recorded intensity index and the maximum seismic response displacement of the frame structure is analyzed. According to the significance of the linear regression equation between various intensity indexes and the maximum seismic response displacement of frame structure, a intensity index that can reasonably describe the characteristic of the double-plateau ground motion is selected. The results show that among the three types of intensity indexes, the correlation between the velocity intensity index and the maximum seismic response displacement of the frame structure is the strongest, the correlation of the displacement intensity index the weakest, and the correlation of acceleration intensity index between the velocity intensity index and the displacement intensity index. Among the speed intensity indexes, the peak velocity has the strongest correlation with the maximum seismic response displacement of the frame structure. There regression results between the peak velocity and the maximum response displacement of the frame structure is the most significant. It is recommended to use the peak velocity as the intensity index for seismic analysis of engineering structures under the double-stationary ground motion.
Existence of Solutions to a Class of Nonlinear Degenerate Elliptic Equation with Lower Order Terms
Xin-xin LI, Wei-lin ZOU
2019, 33(4): 26-30.   doi: 10.3969/j.issn.1001-4926.2019.04.005
Abstract(0) FullText HTML(0) PDF 470KB(0)
Abstract:
In this paper, we mainly study a class of degenerate elliptic equations with lower order terms which growth like sub-p-order growth with respect to the modulus of the gradient of u. Furthermore, the main differential operator may not be coercive on the same space as u becomes large. In order to overcome this difficulty stated above, by using a prior estimation method and approximation theory, we proved the existence and regularity of solutions to such problems.
Preliminary Study on the Universal Model of Layered Structure With Universality
Meng-ying LI, Ming-jun LI
2019, 33(4): 31-38.   doi: 10.3969/j.issn.1001-4926.2019.04.006
Abstract(0) FullText HTML(0) PDF 1680KB(0)
Abstract:
This paper enumerated ubiquitous natural layered materials and artificially layered materials from different fields, such as geography, biology, environment, materials, chemistry and physics, illustrating the extensive existence of layered structures. It has been found that in the high-tech frontier areas, more and more new materials adopt layered structure (such as grapheme, organic solar cells, aviation composites and biomimetic materials)in order to achieve multi-function integration; at the same time, it has been also found that although there are a variety of layered structures, they all objectively have the characteristics of continuity of specific parameters (such as displacement, sound pressure and stress, etc.) on the interlayer interface and recursive influence of each layer in turn. Therefore, for any multi-layered structure in any field, it is an important and fundamental problem to build a universal mathematical model that can reflect these features so as to study its internal correlation and comprehensive overall performance. In this paper, a preliminary discussion has been made on this and the basic framework of the universal model has been established.
Application of Fractional Damping in Fault Diagnosis of Rolling Bearings
Yun-long LI, Zhi-nong LI
2019, 33(4): 39-44, 100.   doi: 10.3969/j.issn.1001-4926.2019.04.007
Abstract(0) FullText HTML(0) PDF 942KB(0)
Abstract:
Fractional calculus has the advantage of high computational precision and fast speed. Therefore, the theory of fractional calculus is applied to the fault diagnosis of rolling bearings. A dynamic model of rolling bearingswith a fault in the inner ring based on fractional damping is established. And the dynamic response characteristic of rolling bearings at optimal order, which isdetermined by the fourth-order center distance of the fractional Fourier transformation, is analyzed. The simulationresults show that the axis motiontrajectory of the inner ring gradually changes from chaotic to stable periodic motionwith the increase of fractional order. And the simulation frequency spectrogram at optimal order is more in line with that of the experiment. The fractional damping model can better reflect the vibration characteristics of rolling bearingswith a fault than the integer damping model and can achieve better results than the traditional integer damping.
Research Progress and Analysis on the Working Properties of Rigid Pile Composite Foundation
Yong-qiang ZOU, Jin-bo LEI, Yan-song YANG, Zhang-fu CHEN, Zhuang-zhuang LI
2019, 33(4): 45-51.   doi: 10.3969/j.issn.1001-4926.2019.04.008
Abstract(0) FullText HTML(0) PDF 523KB(0)
Abstract:
Rigid pile as a kind of bond strength enhancement, has unique advantages in the foundation treatment technology, hence the rigid pile composite foundation been widely used in projects, it’s still many problems haven’t researched yet. This paper briefly introduces the main progress and achievements of domestic experts and scholars in the field of rigid pile composite foundation in recent years, about working characters and influencing factors of the rigid piles composite foundation are analyzed, and on this basis, points out several problems concerning the working properties of the rigid piles composite foundation, then gives some suggestions for peer reference.
Synthesis and Optoelctronic Properties of the Red Phosphorescent Host Material Containing Dibenzothiophene-S,S-dioxide
Gang WAN, Hui-ping XIAO, Jia-qing CAO, Jian-ping ZHOU, Yun-ying Wang, Wei ZHONG, Wen-sheng WENG
2019, 33(4): 52-57, 100.   doi: 10.3969/j.issn.1001-4926.2019.04.009
Abstract(0) FullText HTML(0) PDF 753KB(0)
Abstract:
The alternating copolymer pCzFSO was prepared by using carbazole and dibenzothiophene-S,S-dioxide as the monomers. The UV-vis, photoluminescence, thermal and electrochemical properties of the polymer pCzFSO and its application as a red phosphorescent host material in an electroluminescent device were probed. The results show that the polymer pCzFSO has the thermal decomposition temperature at 426 ℃, it has the band gap at 2.77 eV and the HOMO/LUMO energy levels at −5.65 eV/−2.88 eV. The light-emitting device whose device structure is ITO/PEDOT:PSS/PVK/pCzFSO/Ba/Al comprising the polymer pCzFSO as the light-emitting layer has a maximal luminous efficiency of 0.80 cd/A and a brightness of 635 cd/m2; the phosphorescent photoelectroluminescent device with the device structure ITO/PEDOT:PSS/PVK/pCzFSO:Ir(Piq)3/Ba/Al comprising the polymer pCzFSO as the host material has a maximal luminous efficiency of 1.62 cd/A and a luminance of 1 990 cd/m2. The polymer pCzFSO is a potential red phosphorescent host material.
Synthesis and Characterization of Long Branch-tailed Mesogen Jacketed Polymer Containing Amide Bond
Yi FAN, Li-ying WAN, Xiang RAO, Ming-hui GAO, Kuai-xuan LEI
2019, 33(4): 58-62, 79.   doi: 10.3969/j.issn.1001-4926.2019.04.010
Abstract(0) FullText HTML(0) PDF 957KB(0)
Abstract:
Different from the conventional vinyl terephthalate diester mesogen jacketed liquid crystal polymer, the ester bond of the central bridge was replaced with an amide bond, and an isooctyloxy group was introduced at both ends of the pendant liquid crystal unit. A novel jacketed polymer containing an amide bond and a long-chain alkyloxy tail chain was designed. The structure was determined by fourier transform infrared spectroscopy and nuclear magnetic resonance spectroscopy. The structure and molecular weight were determined by infrared spectroscopy, nuclear magnetic resonance spectroscopy and gel permeation chromatography. The thermal properties of the polymer were investigated by thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). TGA show a decomposition temperature of 378.7 ℃. In the DSC curves, the glass transition temperature is not obvious, and the birefringence of the liquid crystal is not found in POM. This may be due to the introduction of isooctyloxy group, which leads to a decrease in the jacketed effect and makes the polymer non-oriented.
Synthesis and Kinetics of Alicyclic Non-Isocyanate Polyurethane
Cheng-jie JIAO, Ying-feng FENG, Rong ZONG
2019, 33(4): 63-68.   doi: 10.3969/j.issn.1001-4926.2019.04.011
Abstract(0) FullText HTML(0) PDF 812KB(0)
Abstract:
The non-isocyanate polyurethane IPDC was synthesized by rigid alicyclic amine isophorone diamine (IPDA) and propylene carbonate (PC). The structure was characterized by FTIR and 1HNMR. The synthesis kinetics of isophorone diamine and propylene carbonate has been studied. The results showed that the reaction order of IPDA/PC system was 2.201, the apparent activation energy was 35.90 kJ/mol, and the pre-exponential factor was 5.790 min−1. When the reaction temperature was 100 °C, the conversion rate of the system could reach 86.2%.
Influence of Forging Temperature on Ultrasonic Properties of GH4738 Alloy Microstructure based on Ultrasonic C-scanning
Di-qiang GUO, Shi-jing ZHANG, Kai-ge CUI, Wei-ping YUAN, Hong-bo GAO, Guan-hua WU
2019, 33(4): 69-73, 100.   doi: 10.3969/j.issn.1001-4926.2019.04.012
Abstract(0) FullText HTML(0) PDF 999KB(0)
Abstract:
Rapid measurement of ultrasonic characteristic parameters related to microstructure is the key for studying the influence of hot forging process on the microstructure of super alloy and its ultrasonic nondestructive evaluation. In this paper, the ultrasonic longitudinal wave velocity and attenuation coefficient of 4738 superalloy with different forging temperature were measured automatically by using water immersion ultrasonic testing system and high-efficiency ultrasonic C-scan method, and the influence of forging temperature on the ultrasonic properties of alloy microstructure was analyzed. The results show that the good linear correlation can be observed between forging temperature and velocity and attenuation coefficient, which can objectively reflect the effect of forging temperature on the ultrasonic properties of microstructure. The C-scan images based on different ultrasonic characteristic parameters are helpful to show the difference of material structure in different regions, and provide auxiliary means for the screening of heat treatment microstructure and the establishment of hot forging process for a large number of GH4738 raw materials.
Error Analysis of Measuring Metal Mechanical Properties in High-temperature by Moiré interferometer
Chen-yu ZHANG, Bei YANG, Qiong WU, Ai-min DONG
2019, 33(4): 74-79.   doi: 10.3969/j.issn.1001-4926.2019.04.013
Abstract(0) FullText HTML(0) PDF 675KB(0)
Abstract:
The Metal Mechanical Properties have been successfully tested by Moiré interferometer in high-temperature. The grating frequency of metal zero thickness determines the measurement accuracy in this experiment. This paper have discussed the influence of temperature and load to the grating line frequency, and calculated the measurement error. The error caused by thermal deformation is 0.84%, while caused by load is 0.17% for the aluminum alloy on 300 ℃. The error caused by thermal deformation is 1.52%, while caused by load is 0.34% for Ni-Cr alloy on 1 000 ℃. We can conclude that the thermal deformation of temperature is the main factor for the measurement error, and a modified calculation method is also proposed in this paper.
Improvement of An Aluminum Alloy Template Based on ANSYS
Ke-song LUO, Shao-qin ZHANG, Sheng LUO, Mu-gen YAO, Ri-liang ZENG, Jin-zi CHEN, Zi-qi NIE
2019, 33(4): 80-87.   doi: 10.3969/j.issn.1001-4926.2019.04.014
Abstract(0) FullText HTML(0) PDF 1256KB(0)
Abstract:
The theoretical analysis results of the aluminum ribbed cross-ribbed formwork are in good agreement with the finite element analysis results. The simulation results have certain reliability. Then the ANSYS finite element software was used to simulate the three-dimensional finite element simulation of the aluminum alloy formwork pull-tab system and several modified wall molds under the load of construction. The calculation results show that the large values of lateral deformation and bending stress appear in the middle and lower part of the wall mold. Adjusting the size and spacing of the longitudinal and transverse ribs can effectively change the force deformation characteristics of the wall mold during construction and better ensure the pouring wall. The three improved schemes reduce the maximum lateral deformation of the wall mold to varying degrees under the premise of a small increase in the material (not more than 10%). The maximum lateral deformation value of the improved scheme 3 is reduced by 65.25% compared with the existing wall mold, which is the best improvement scheme.
Seismic Behavior of Joints in Additional Angle Steel Prestressed Assembly Frames Based on ABAQUS
Yan FU, Ling HUANG
2019, 33(4): 88-93, 104.   doi: 10.3969/j.issn.1001-4926.2019.04.015
Abstract(0) FullText HTML(0) PDF 1514KB(0)
Abstract:
Based on the experimental study on seismic behavior of joints in additional angle steel prestressed assembly frames, this paper uses ABAQUS software to numerically simulate and analyze the influence of different factors on the skeleton curve and ultimate load. The results show that the finite element analysis results are in good agreement with the experimental results, which proves that the finite element analysis method used in this paper is reliable; increasing the axial compression ratio, effective prestress, and concrete strength grade can enhance the bearing capacity of the node within a certain range. Capacity and the increase of the normal longitudinal reinforcement ratio of the beam have little effect on the bearing capacity of the joint. This study can provide a reference for seismic design of prestressed fabricated frame structures with additional angle steel.
Characteristics of Acoustic Emission Signals for TB6 Titanium Alloy Fatigue Test Process
Zi-hang WEI, Xin-min LI, Xian-hui ZHANG, Zi-rong YU
2019, 33(4): 94-100.   doi: 10.3969/j.issn.1001-4926.2019.04.016
Abstract(0) FullText HTML(0) PDF 1191KB(0)
Abstract:
With the wide use of helicopters, it becomes more and more significant to detect the fatigue crack in critical component during the period of its high strength running, and conventional non-destructive testing technology cannot monitor the generation and changes of cracks in real time. TB6 titanium alloy, a common component material of helicopter, was fatigue fracture tested. The acoustic emission (AE) signals during the test were collected by AE detection technology. Wavelet energy coefficient historical variety analysis method, combined with characteristic parameter historical variety analysis and wavelet analysis, was adopted to study the characteristic variation of signal. The results show that the fatigue fracture process of the material has experienced four stages, and the AE characteristics of each stage have obvious turning points. At the beginning of crack initiation, characteristic parameter and wavelet energy coefficient have obvious jump, and the center frequency of the AE signal tends to move toward the high frequency with time. These characteristic laws provide a reference for the AE dynamic monitoring and health evaluation of TB6 titanium alloy components.
Estimating UAV Altitude Based on Kalman Filter
Wei-jun TU, Qi-hui SHENG, Xiao-mei WANG
2019, 33(4): 101-104.   doi: 10.3969/j.issn.1001-4926.2019.04.017
Abstract(0) FullText HTML(0) PDF 689KB(0)
Abstract:
The quality of UAV(Unmanned Aerial Vehicle) altitude signals directly influences the precision of altitude control. The altitude, vertical velocity and vertical acceleration of UAV provided by the barometric altitude sensor, GPS, and INS, respectively in this paper are used to establish state equation and calibration equation. Subsequently the altitude information fusion obtained from sensors is realized by Kaman filter, and used to estimate the practical altitude. The mathematical simulation results in more precise altitude signal when compared to the single sensor. This study could provide a reference for UAV control technology design.
Application of Simulation Technology in Microcomputer Principle Course Teaching and Practice
Wen WAN, Yan-feng GAO, Li-zhen CUI, Kang-kang LI
2019, 33(4): 105-109.   doi: 10.3969/j.issn.1001-4926.2019.04.018
Abstract(0) FullText HTML(0) PDF 783KB(0)
Abstract:
Proteus simulation technology is introduced into classroom teaching and practice to enrich teaching content through case simulation demonstration, deepen students' understanding of theoretical knowledge and improve the teaching quality of the course in a more intuitive and visual way of teaching. The "theory, simulation, practice" three-level progressive teaching model runs through the whole teaching process, focusing on the combination of knowledge and practice application ability, so that students can get engineering training in the process of solving problems, so that students can get all-round training in all aspects of teaching, and improve their interest in learning and innovation ability.
Improving EFL Learners’ Temporal Variables of Oral Fluency Based on WeChat: An Empirical Study
Hui-qi WU
2019, 33(4): 110-115.   doi: 10.3969/j.issn.1001-4926.2019.04.019
Abstract(0) FullText HTML(0) PDF 509KB(0)
Abstract:
Intelligent-terminal-based English speaking and listening has been gaining more and more concerns. In view of the existing problems in the traditional English class teaching, the model of classroom teaching +voice-based WeChat is proposed in this research for oral English teaching. Compared with the model of classroom teaching +face-to-face communication, the comparative research found that the gain scores on the measure of participants in the former model were significantly higher on the temporal variables of oral fluency, and the application of the former model could improve the students' learning participation and relieve their anxiety, finally providing instructive advice for the improvement of oral fluency based on internet-mediated communication.
Key Factors of Improving the Comprehensive Quality of University Teachers Based on Gt-AHP Under the Background of “Double First-Class” Initiative
Guang-quan ZHOU, Qin ZHOU
2019, 33(4): 116-122.   doi: 10.3969/j.issn.1001-4926.2019.04.020
Abstract(0) FullText HTML(0) PDF 646KB(0)
Abstract:
Under the background of "double first-class" construction, the comprehensive quality of teachers has become an important aspect to promote the development of colleges and universities. However, the research on the comprehensive quality of domestic college teachers has serious problems in terms of ideological and moral, teaching ability and scientific research. Firstly, it analyzed 11 domestic related literatures on teachers' comprehensive quality. Through comparative analysis, rooted theory, and the establishment of a hierarchy analysis model of teachers' comprehensive quality, it extracted 16 kinds of influencing factors on teachers' comprehensive quality, and found out five key factors provide theoretical support for improving the quality of domestic college teachers.
Computation of the Stress Intensity Factor Based on the Interaction Integral Method
GONG Jing-quan, ZHANG Shao-qin, LI He, ZHANG Chen-yu
2015, 29(1): 42-48.   doi: 10.3969/j.issn.1001-4926.2015.01.007
Abstract(77) PDF 833KB(204)
Researches and Designs on Smart Vehicles Parking System Based on NB-IoT
DONG Yu-rong, NIE Yun-feng
2017, 31(3): 95-99.   doi: 10.3969/j.issn.1001-4926.2017.03.016
Abstract(370) PDF 724KB(13)
Status and Development of Dacromet Coating
ZHOU Ci-xin, ZHOU Ya
2014, 28(2): 43-49.   doi: 10.3969/j.issn.1001-4926.2014.02.008
Abstract(54) PDF 877KB(117)
The Numerical Simulation Analysis for Excess Pore Water Pressure of Pipe-pile with Hole
YI Fei, LEI Jin-bo, HE Li-jun, LE Teng-sheng, ZHOU Xing
2015, 29(1): 72-76.   doi: 10.3969/j.issn.1001-4926.2015.01.012
Abstract(47) PDF 791KB(77)
Experimental about Monitoring the Crack of the Q345 Steel after Tensile and Bending by Acoustic Emission
MO Ya-jing, LI Qiu-feng, HE Cai-hou, LI Shuai-hui, CHEN Ji-le
2015, 29(1): 55-60.   doi: 10.3969/j.issn.1001-4926.2015.01.009
Abstract(53) PDF 840KB(80)
Exploration on Integration of Mathematics Thought and Methods with Teaching of Linear Algebra
LI Xi
2014, 28(3): 105-108.   doi: 10.3969/j.issn.1001-4926.2014.03.018
Abstract(64) PDF 740KB(100)
Simulation Status Analysis of Near-field Strong Ground Motion
ZHONG Ju-fang
2014, 28(2): 1-8.   doi: 10.3969/j.issn.1001-4926.2014.02.001
Abstract(53) PDF 779KB(103)
Research on Calculation Method of Ground Settlement Induced by Subway Shield Tunelling Construction
JIANG An-long
2014, 28(1): 101-108.   doi: 10.3969/j.issn.1001-4926.2014.01.019
Abstract(75) PDF 885KB(101)
Dynamics Modeling and Simulation on Rolling Bearing Element with Single Outer Race Defect
REN Shuai, XU Ke-jun, QIN Hai-qin, LI Zhi-nong
2014, 28(1): 85-90.   doi: 10.3969/j.issn.1001-4926.2014.01.016
Abstract(80) PDF 803KB(87)
Development and Experiment of Two-dimensional Magnetic Memory Testing Instrument
REN Ji-lin, DENG Yin, LIU Hai-chao, HU Zhi, ZHANG Lu-geng
2014, 28(4): 43-49.   doi: 10.3969/j.issn.1001-4926.2014.04.009
Abstract(66) PDF 1100KB(117)

Start publication: 1987

Frequency: Quarterly

Competent unit: Journal of NanChang HangKong University

Host unit: Journal of NanChang HangKong University

Editor: Shenglian Luo

ISSN: 1001-4926

CN: 36-1303/N

Price: CNY 15.00