DESIGN AND HYBRID CONTROL OF A NEW SELF-POWERED ELECTROMAGNETIC SUSPENSION ACTUATOR MATCHED WITH NON-PNEUMATIC TIRE

Yu Jiang,Ruochen Wang,Renkai Ding,Yazhou Zhou 한국자동차공학회 2023 International journal of automotive technology Vol.24 No.1

To improve the dynamic performance of non-pneumatic tire vehicle (NPTV) and recover the suspension vibration energy, a new self-powered electromagnetic suspension actuator matching non-pneumatic tire (NPT) with passive damping is proposed. Firstly, the mathematical model of the NPTV suspension system are established based on experiments. Secondly, the key performance parameters, passive damping and rated electromagnetic thrust, of the electromagnetic actuator are optimized, and its’ specific structure is designed. Then, a hybrid control strategy is proposed. Compared with the passive suspension, the body acceleration and suspension travel of NPTV are reduced by 9.09 % and 10.45 % respectively. Additionally, the proposed actuator can compensate the consumed power to realize self-power. Finally, a bench test is carried out, which verifies the effectiveness and superiority of the designed electromagnetic suspension actuator.

Simulation of non-Gaussian stochastic processes by amplitude modulation and phase reconstruction

Yu Jiang,Junyong Tao,Dezhi Wang 한국풍공학회 2014 Wind and Structures, An International Journal (WAS Vol.18 No.6

Stochastic processes are used to represent phenomena in many diverse fields. Numerical simulation method is widely applied for the solution to stochastic problems of complex structures when alternative analytical methods are not applicable. In some practical applications the stochastic processes show non-Gaussian properties. When the stochastic processes deviate significantly from Gaussian, techniques for their accurate simulation must be available. The various existing simulation methods of non-Gaussian stochastic processes generally can only simulate super-Gaussian stochastic processes with the high-peak characteristics. And these methodologies are usually complicated and time consuming, not sufficiently intuitive. By revealing the inherent coupling effect of the phase and amplitude part of discrete Fourier representation of random time series on the non-Gaussian features (such as skewness and kurtosis) through theoretical analysis and simulation experiments, this paper presents a novel approach for the simulation of non-Gaussian stochastic processes with the prescribed amplitude probability density function (PDF) and power spectral density (PSD) by amplitude modulation and phase reconstruction. As compared to previous spectral representation method using phase modulation to obtain a non-Gaussian amplitude distribution, this non-Gaussian phase reconstruction strategy is more straightforward and efficient, capable of simulating both super-Gaussian and sub-Gaussian stochastic processes. Another attractive feature of the method is that the whole process can be implemented efficiently using the Fast Fourier Transform. Cases studies demonstrate the efficiency and accuracy of the proposed algorithm.

Experimental Study of Seismic Damage with Park-Ang Model for Recycled Aggregate Concrete Columns

Yujiang Fan,Ziqiang Guo,Yachao Wang,Pengcheng Zhao,Binshan Yu 대한토목학회 2021 KSCE JOURNAL OF CIVIL ENGINEERING Vol.25 No.9

By means of the low cycle loading tests on six recycled aggregate concrete (RAC) columns with different proportions, in combination with the Park-Ang two-parameter damage model suitable for ordinary concrete columns and the damage degree Dc of actual structures, the calculated value of cyclic loading coefficient β of recycled aggregate concrete columns was determined. It would be achieved by analyzing the calculated β that the impact of the replacement ratio of recycled aggregate and the content of mixed fibers on β was significantly different. Considering the reinforcement ratio mentioned in paper. Matlab was further employed to fit multivariable linear equation regarding recycled aggregate replacement ratio, mixed fibers contents and reinforcement rate as the basis, so that the computation formula of the cyclic loading coefficient β suitable for recycled aggregate concrete columns was revealed.

Rapid and effective removal of sodium lignosulfonate from aqueous solutions by in-situ formed magnesium hydroxide

Tao Wu,Yujiang Li,Lanlan Ye,Feng Li 한국화학공학회 2016 Korean Journal of Chemical Engineering Vol.33 No.12

We investigated the efficiency of in-situ formed magnesium hydroxide (Mg(OH)2) for the removal of sodium lignosulfonate (SLSN) from aqueous solution. Adsorption experiments considered the effects of various conditions such as pH, MgCl2 concentration, contact time, and temperature on SLSN removal efficiency. It was found that approximately 93%-99% SLSN was removed by in-situ formed Mg(OH)2. The adsorption was rapid, and the contact time required to reach complete adsorption equilibrium was less than 2min. Moreover, that the Mg(OH)2 lost about 0.5-3.0% adsorption capacity for SLSN when NO3 −, HCO3 −, H2PO4 − and SO4 2− anions were simultaneously present with SLSN. The experimental data suggested that there was little competitive adsorption of SLSN with other coexisting anions on Mg(OH)2. The co-precipitation/adsorption process was exothermic and physical, involving weak interactions such as electrostatic attraction, hydrogen bonding, adhesive forces, and van der Waals forces between SLSN molecules and the binding sites on Mg(OH)2.

Preparation of nano-TiO2/purified diatomite coating and its photocatalytic properties of formaldehyde degradation

Lijian Wang,Junwei Zhao,Yujiang Wang,Shuilin Zheng 한양대학교 세라믹연구소 2020 Journal of Ceramic Processing Research Vol.21 No.6

The nano-TiO2/purified diatomite composite materials with core-shell structures were prepared by hydrolysis precipitationusing purified diatomite as carrier and titanium sulfate as precursor. The composite materials were characterized bytransmission electron microscope (TEM), X-ray diffraction (XRD), low temperature nitrogen adsorption and mercuryporosimetry. The photocatalytic composite coating based on the nano-TiO2/prified diatomite composite materials wasprepared and its properties of formaldehyde degradation were investigated. Meanwhile, the degradation mechanism offormaldehyde gas was discussed. The results showed that the nano-TiO2/prified diatomite composite materials were formedcore-shell structures, and the TiO2 nanoparticles were anatase with the average size of about 10 nm?The test results show thatthe formaldehyde purification performance of the coatings has met the technical requirements of Class I materials in theChinese national standard JC/T 1074-2008.

Tetrasodium iminodisuccinate assisted hydrothermal synthesis and upconversion luminescence of NaYF4: Yb3+, Er3+ hexagonal nanoplates

Haiyan Lin,Zikun Wang,Yujiang Wang,Junwei Zhao 한양대학교 세라믹연구소 2020 Journal of Ceramic Processing Research Vol.21 No.6

Yb3+/Er3+ co-doped NaYF4 (NaYF4: Yb3+, Er3+) hexagonal nanoplates were synthesized by a tetrasodium iminodisuccinateassisted hydrothermal synthesis method for the first time. The crystal structure and morphology was investigated by the Xraydiffraction and scanning electron microscope analysis. The upconversion luminescent property of the synthesized NaYF4:Yb3+, Er3+ hexagonal nanoplates was discussed as a function of Yb3+ and Er3+ concentration. Under 980 nm excitation, NaYF4:Yb3+, Er3+ hexagonal nanoplates exhibited strong red emissions near 660 nm and green upconversion emissions at 530 and 550nm corresponding to the intra 4f transitions of Er3+ (4F9/2, 2H11/2, 4S3/2) → Er3+ (4I15/2). The Yb3+ 5 mol% and Er3+ 0.5 mol%co-doped NaYF4 sample exhibited strongly shiny upconversion emission, which was considered to be the optimum dopingconcentration. A possible upconversion mechanism for NaYF4: Yb3+, Er3+ depending was discussed in detail.

Two-Sided Contact Mesh Stiffness and Transmission Error for a Type of Backlash-Compensated Conical Involute Gear Pair

Shuaidong Zou,Guangjian Wang,Yujiang Jiang 한국정밀공학회 2020 International Journal of Precision Engineering and Vol.21 No.7

Both the drive- and back-side contact mesh stiff nesses (two-sided contact mesh stiff ness) for a new type of conical involute gear (NTCIG) is developed analytically. Instead of the conventional spring preload anti-backlash method, an active control strategy to eliminate the time-varying backlash is presented by adjusting the axial displacement of the driven gear. The dynamic transmission error (DTE) of the gear pair is calculated under different load excitations to analyze the differences between the drive- and back-side meshes under a time-varying backlash with anti-backlash conditions based on the NTCIG model with an eccentricity error. Considering the additional rotational angle caused by the anti-backlash and the differences from the two-sided contact, the theory of no-load transmission error for the NTCIG is modified by agreeing considerably well with the low component of the DTE. Moreover, the DTE curve under varying load excitations showed that the dynamics of the NTCIG improved considerably after backlash compensation. The drive- and back-side tooth meshes were analyzed according to the DTE of NTCIG with backlash control under various external excitations at different speeds and variable initial phases, frequencies, and amplitudes of the sinusoidal load.

Controlled synthesis of SrCO3 dendrites by a simple hydrothermal method

Yonggang Wang,Linlin Yang,Xiaofeng Wang,Yujiang Wang,GAORONG HAN 한양대학교 세라믹연구소 2015 Journal of Ceramic Processing Research Vol.16 No.2

In this paper, we report the controlled synthesis of SrCO3 crystals by a simple hydrothermal method without any surfactants and templates. The as-prepared samples were characterized by X-ray powder diffraction (XRD) and transmission electron microscopy (TEM). The effect of pH value, temperature, and reaction time on the formation of SrCO3 crystals was investigated. This novel route is proved to be simple and environment-friendly, which can be extended to the shape-controlled synthesis of other metal oxide nanocrystals.

Controlled synthesis and characterization of BiVO4 dendrites via a hydrothermal method

Yonggang Wang,Linlin Yang,Xiaofeng Wang,Yujiang Wang,GAORONG HAN 한양대학교 세라믹연구소 2016 Journal of Ceramic Processing Research Vol.17 No.7

BiVO4 dendrites have been controllably synthesized by a hydrothermal method without any surfactants or templates. Thestructure and morphology of the obtained BiVO4 dendrites were characterized by X-ray powder diffraction, scanning electronmicroscope, transmission electron microscopy, and high-resolution transmission electron microscopy. The effect of the pHvalues, precursors, solution concentrations, reaction temperature, and reaction time on the morphology and structure of theBiVO4 dendrites was systematically studied for the first time. It is found that the morphologies of the obtained BiVO4crystallites can vary from cubic-like to dendritic shape. The BiVO4 dendrites can be successfully fabricated by thehydrothermal method at 150 oC and pH 7 when Bi2(CO3)3 and NH4VO3 were used as precursors The resultant dendriticstructure has four trunks which have ordered branches on the opposite sides of the trunks. A rational mechanism for theoriental growth of the BiVO4 dendrites is discussed. The preparation of BiVO4 dendrites with well-dened shapes may open newopportunities for wide applications of future nanodevices.

Enhanced adsorption capacity of dyes by surfactant-modified layered double hydroxides from aqueous solution

Bei Zhang,Zhihao Dong,Dejun Sun,Tao Wu,Yujiang Li 한국공업화학회 2017 Journal of Industrial and Engineering Chemistry Vol.49 No.-

The utilization of organo-modified layered double hydroxides with anionic surfactants (organo-LDHs) asadsorbents were successfully carried out to remove various synthetic dyes from aqueous solution. Intercalation of anionic surfactants changed the surface properties of MgAl-LDH from hydrophilic tohydrophobic, and a charge inversion occurred with increasing the length of surfactant chains. Suchchanges in the surface properties of the organo-LDHs were important. Experimental data shown that theSNS-modified MgAl-LDH could be used as a broad-spectrum adsorbent to effectively remove anionic,non-ionic, and cationic dyes from aqueous solution.