Bearing Fault Diagnosis Based on Wavelet Packet Decomposition Energy Distribution and Gray Similar Correlation Degree

Zhang Zhigang,Qin Hongmao,Sun Ning 보안공학연구지원센터 2016 International Journal of u- and e- Service, Scienc Vol.9 No.2

For rolling bearing fault, there is a certain mapping relationship between failure state and its each frequency band energy and distribution, this paper proposes a bearing fault diagnosis method based on wavelet packet decompotion energy distribution and gray similar correlation degree. Introducing a concept of soft morphological filtering, combined the EMD method on the original vibration signal de-noising pretreatment. Decomposing bearing vibration acceleration signal after noise reduction into different frequency band signal by adopting the method of wavelet packet decomposition and calculating the energy distribution. Due to the gray similar correlation degree analysis for the classification of the small sample pattern recognition has a good effect, element structure characteristic vector by energy distribution, to judge the fault types by calculating the bearing vibration signal under different status similar correlation degree. Experimental results show that, the proposed can be effectively applied to bearing fault diagnosis.

SIMULATION AND MODELING OF DYNAMIC FRICTION COEFFICIENT OF WET CLUTCH DURING ENGAGEMENT

Zhigang Zhang,Ling Zou,Hang Liu,Yonglong Chen,Benzhu Zhang 한국자동차공학회 2022 International journal of automotive technology Vol.23 No.1

A dynamic friction coefficient model in engagement was established based on the friction transmission mechanism of a wet clutch. The effects of parameters, such as the material permeability, surface roughness, Young’s modulus, ATF viscosity, applied pressure, initial relative angular velocity, and pressure delay time, on the friction coefficient during engagement were investigated. The results indicated that material permeability has a greater influence on the time when the dynamic friction coefficient tends to be stable, choosing an appropriate permeability of friction material can effectively prevent excessive the level of jerk during the engagement and excessive engagement time. Surface roughness and applied pressure mainly affect the magnitude of the initial and midpoint friction coefficients. Appropriately increasing the surface roughness and applied pressure can increase the smoothness of the engagement of wet clutch. The ATF viscosity and initial relative angular velocity have a significant effect on the magnitude of the initial friction coefficients. Appropriately increasing the ATF viscosity and initial relative angular velocity will reduce the level of jerk at the end of the wet clutch engagement. Young’s modulus and the pressure delay time have a smaller effect on the dynamic friction coefficient than that of other parameters.

Synthesis of acetic acid-[(hydrazinylthioxomethyl)thio]-sodium and its application on the flotation separation of molybdenite from galena

Zhigang Yin,Wei Sun,Yuehua Hu,Runqing Liu,Wei Jiang,Chenhu Zhang,Qingjun Guan,Chenyang Zhang 한국공업화학회 2017 Journal of Industrial and Engineering Chemistry Vol.52 No.-

A novel organic compound acetic acid-[(hydrazinylthioxomethyl)thio]-sodium was synthesized andcharacterized. Theflotation performance and adsorption mechanism of AHS to galena were investigatedby micro, benchflotation tests, UV spectra, zeta potential, FTIR and XPS measurements. The resultsdemonstrated that AHS exhibited superior depressing power to galena and could be used as selectivedepressant forflotation separation of molybdenite from galena. The results of UV spectra, FTIR, zetapotential and XPS measurements demonstrated that AHS chemisorb on galena surface by formingfivememberedcheat ring with releasing of H ions. Therefore, the possible adsorption mode of AHS on galenasurface was recommended.

Single-Point Grinding of Alumina and Zirconia Ceramics Under Two-Dimensional Compressive Prestress

Gaofeng Zhang,Zhigang Wang,Wenxin Chen,Jingtao Li,Hao Sun,Kui Zhang 한국정밀공학회 2020 International Journal of Precision Engineering and Vol.21 No.1

In this study, single-point grinding experiments were performed on alumina and zirconia ceramics to investigate the grinding processes under two-dimensional compressive prestress (TCP). Grinding forces and grooves were measured under different values of TCP to evaluate the grinding defects. The material removal rate and actual grinding depth were exploited to investigate the grinding-induced damage and material

Protective effect of resveratrol on arsenic trioxide-induced nephrotoxicity in rats

Weiqian Zhang,Yan Liu,Ming Ge,Jiang Jing,Yan Chen,Huijie Jiang,Hongxiang Yu,Ning Li,Zhigang Zhang 한국영양학회 2014 Nutrition Research and Practice Vol.8 No.2

BACKGROUND/OBJECTIVES: Arsenic, which causes human carcinogenicity, is ubiquitous in the environment. This study was designed to evaluate modulation of arsenic induced cancer by resveratrol, a phytoalexin found in vegetal dietary sources that has antioxidant and chemopreventive properties, in arsenic trioxide (As₂O₃)-induced Male Wistar rats. MATERIALS/METHODS: Adult rats received 3 mg/kg As₂O3 (intravenous injection, iv.) on alternate days for 4 days. Resveratrol(8 mg/kg) was administered (iv.) 1 h before As₂O₃ treatment. The plasma and homogenization enzymes associated with oxidative stress of rat kidneys were measured, the kidneys were examined histologically and trace element contents were assessed. RESULTS: Rats treated with As₂O₃ had significantly higher oxidative stress and kidney arsenic accumulation; however, pretreatment with resveratrol reversed these changes. In addition, prior to treatment with resveratrol resulted in lower blood urea nitrogen, creatinine and insignificant renal tubular epithelial cell necrosis. Furthermore, the presence of resveratrol preserved the selenium content (0.805 ± 0.059 μg/g) of kidneys in rats treated with As₂O₃. However, resveratrol had no effect on zinc level in the kidney relative to As₂O₃-treated groups. CONCLUSIONS: Our data show that supplementation with resveratrol alleviated nephrotoxicity by improving antioxidant capacity and arsenic efflux. These findings suggest that resveratrol has the potential to protect against kidney damage in populations exposed to arsenic.

<i>OsASR5</i> enhances drought tolerance through a stomatal closure pathway associated with ABA and H ₂ O ₂ signalling in rice

Li, Jinjie,Li, Yang,Yin, Zhigang,Jiang, Jihong,Zhang, Minghui,Guo, Xiao,Ye, Zhujia,Zhao, Yan,Xiong, Haiyan,Zhang, Zhanying,Shao, Yujie,Jiang, Conghui,Zhang, Hongliang,An, Gynheung,Paek, Nam‐,Cho John Wiley and Sons Inc. 2017 Plant biotechnology journal Vol.15 No.2

<P><B>Summary</B></P><P>Drought is one of the major abiotic stresses that directly implicate plant growth and crop productivity. Although many genes in response to drought stress have been identified, genetic improvement to drought resistance especially in food crops is showing relatively slow progress worldwide. Here, we reported the isolation of <I>abscisic acid</I>,<I> stress</I> and <I>ripening</I> (<I>ASR</I>) genes from upland rice variety, IRAT109 (<I>Oryza sativa</I> L. ssp. <I>japonica</I>), and demonstrated that overexpression of <I>OsASR5</I> enhanced osmotic tolerance in <I>Escherichia coli</I> and drought tolerance in <I>Arabidopsis</I> and rice by regulating leaf water status under drought stress conditions. Moreover, overexpression of <I>OsASR5</I> in rice increased endogenous ABA level and showed hypersensitive to exogenous ABA treatment at both germination and postgermination stages. The production of H<SUB>2</SUB>O<SUB>2</SUB>, a second messenger for the induction of stomatal closure in response to ABA, was activated in overexpression plants under drought stress conditions, consequently, increased stomatal closure and decreased stomatal conductance. In contrast, the loss‐of‐function mutant, <I>osasr5</I>, showed sensitivity to drought stress with lower relative water content under drought stress conditions. Further studies demonstrated that OsASR5 functioned as chaperone‐like protein and interacted with stress‐related HSP40 and 2OG‐Fe (II) oxygenase domain containing proteins in yeast and plants. Taken together, we suggest that <I>OsASR5</I> plays multiple roles in response to drought stress by regulating ABA biosynthesis, promoting stomatal closure, as well as acting as chaperone‐like protein that possibly prevents drought stress‐related proteins from inactivation.</P>

Temporal and Spatial Traffic Analysis Based on Human Mobility for Energy Efficient Cellular Network

( Zhigang Li ),( Xin Wang ),( Junsong Zhang ),( Wei Huang ),( Ye Tian ) 한국인터넷정보학회 2021 KSII Transactions on Internet and Information Syst Vol.15 No.1

With the drastic growth of Information and Communication Technology (ICT) industry, global energy consumption is exponentially increased by mobile communications. The huge energy consumption and increased environmental awareness have triggered great interests on the research of dynamic distribution of cell user and traffic, and then designing the energy efficient cellular network. In this paper, we explore the temporal and spatial characteristics of human mobility and traffic distribution using real data set. The analysis results of cell traffic illustrate the tidal effect in temporal and spatial dimensions and obvious periodic characteristics which can be used to design Base Station (BS) dynamic with sleeping or shut-down strategy. At the same time, we designed a new Cell Zooming and BS cooperation mode. Through simulation experiments, we found that running in this mode can save about 35% of energy consumption and guarantee the required quality of service.

Predictive Current Control of Four-Quadrant Converters Based on Specific Sampling Method and Modified Z-Transform

Zhang, Gang,Qian, Jianglin,Liu, Zhigang,Tian, Zhongbei The Korean Institute of Power Electronics 2019 JOURNAL OF POWER ELECTRONICS Vol.19 No.1

Four-quadrant converters (4QCs) are widely used as AC-DC power conversion interfaces in many areas. A control delay commonly exists in the digital implementation process of 4QCs, especially for high power 4QCs with a low switching frequency. This usually results in alternating current distortion, increased current harmonic content and system instability. In this paper, the control delay is divided into a computation delay and a PWM delay. The impact of the control delay on the performance of a 4QC is briefly analyzed. To obtain a fundamental value of AC current that is as accurately as possible, a specific sampling method considering the PWM pattern is introduced. Then a current predictive control based on a modified z-transform is proposed, which is effective in reducing the control delay and easy in terms of digital implementation. In addition, it does not depend on object models and parameters. The feasibility and effectiveness of the proposed predictive current control method is verified by simulation and experimental results.

Mechanical and Engineering Behavior of MICP-Treated Coarse Siliceous Sands

Zhigang Shan,Peng Zhang,Hailei Kou 대한토목학회 2022 KSCE JOURNAL OF CIVIL ENGINEERING Vol.26 No.1

Microbial-induced calcium carbonate precipitation (MICP) technology has been widely used in geotechnical engineering. The undrained and unconsolidated (UU) triaxial tests were conducted in this study to investigate the effect of bio-cementation concentration and treatment times on the mechanical behavior of MICP treated siliceous sands. Test results indicated that the strength of treated specimen is significantly affected by the bio-cementation concentration. The normalized σ 'p/σ 'p_u increases exponentially with treatment times and produced calcium carbonate. For the same treatment times, the higher the bio-cementation concentration, the larger the produced calcium carbonate and smaller corresponding failure strain. The void ratio and permeability of treated specimens decrease lineally with treatment times increase. The higher the used bio-cementation concentration, the larger the reduction of void ratio and permeability. SEM analysis illustrates that when the bio-cementation concentration is 0.5 mol/L, the crystal form of calcium carbonate is mainly spherical, while the concentrations are 0.7 mol/L and 1.0 mol/L, the crystal form of calcium carbonate is mainly block. This can explain from the perspective that the treatment effect of 0.7 mol/L and 1.0 mol/L bio-cement cementation is better than that of 0.5 mol/L.

Expression of FKBP prolyl isomerase 5 gene in tissues of muscovy duck at different growth stages and its association with muscovy duck weight

Hu Zhigang,Ge Liyan,Zhang Huilin,Liu Xiaolin 아세아·태평양축산학회 2022 Animal Bioscience Vol.35 No.1

Objective: FKBP prolyl isomerase 5 (FKBP5) has been shown to play an important role in metabolically active tissues such as skeletal muscle. However, the expression of FKBP5 in Muscovy duck tissues and its association with body weight are still unclear. Methods: In this study, real-time quantitative polymerase chain reaction was used to detect the expression of FKBP5 in different tissues of Muscovy duck at different growth stages. Further, single nucleotide polymorphisms (SNPs) were detected in the exon region of FKBP5 and were combined analyzed with the body weight of 334 Muscovy ducks. Results: FKBP5 was highly expressed in various tissues of Muscovy duck at days 17, 19, 21, 24, and 27 of embryonic development. In addition, the expression of FKBP5 in the tissues of female adult Muscovy ducks was higher than that of male Muscovy ducks. Besides, an association analysis indicated that 3 SNPs were related to body weight trait. At the g.4819252 A>G, the body weight of AG genotype was significantly higher than that of the AA and the GG genotype. At the g.4821390 G>A, the genotype GA was extremely significantly related to body weight. At the g.4830622 T>G, the body weight of TT was significantly higher than GG and TG. Conclusion: These findings indicate the possible effects of expression levels in various tissues and the SNPs of FKBP5 on Muscovy duck body weight trait. FKBP5 could be used as molecular marker for muscle development trait using early marker-assisted selection of Muscovy ducks. Objective: FKBP prolyl isomerase 5 (FKBP5) has been shown to play an important role in metabolically active tissues such as skeletal muscle. However, the expression of FKBP5 in Muscovy duck tissues and its association with body weight are still unclear.Methods: In this study, real-time quantitative polymerase chain reaction was used to detect the expression of FKBP5 in different tissues of Muscovy duck at different growth stages. Further, single nucleotide polymorphisms (SNPs) were detected in the exon region of FKBP5 and were combined analyzed with the body weight of 334 Muscovy ducks.Results: FKBP5 was highly expressed in various tissues of Muscovy duck at days 17, 19, 21, 24, and 27 of embryonic development. In addition, the expression of FKBP5 in the tissues of female adult Muscovy ducks was higher than that of male Muscovy ducks. Besides, an association analysis indicated that 3 SNPs were related to body weight trait. At the g.4819252 A>G, the body weight of AG genotype was significantly higher than that of the AA and the GG genotype. At the g.4821390 G>A, the genotype GA was extremely significantly related to body weight. At the g.4830622 T>G, the body weight of TT was significantly higher than GG and TG.Conclusion: These findings indicate the possible effects of expression levels in various tissues and the SNPs of FKBP5 on Muscovy duck body weight trait. FKBP5 could be used as molecular marker for muscle development trait using early marker-assisted selection of Muscovy ducks.