Multi-objectives topology optimization of frame in an electric mining dump truck based on fuzzy satisfaction variable weight coefficients method

Jinhua Liu,Liang Luo,Xuewen Xiao,Chen Zhang,Ling Zhang,Chengji Mi 대한기계학회 2022 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.36 No.6

In order to optimize the stiffness and strength and modal characteristics of frame in an electric mining dump truck determined by experiential design, the multi-objectives topology optimization is the most frequently used method. However, each single objective satisfaction degree has fuzziness when it comes to solve engineering problems. In this paper, a novel fuzzy multi-objective topology optimization method based on fuzzy satisfaction variable weight coefficients was presented. Based on the variable density method and SIMP interpolation model, the single objective topology optimization design under different conditions was performed. The fuzzy membership function was utilized to measure the sub-objective fuzzy satisfaction degree of frame. The weight factor of each single objective was dynamically assigned through variable weight approach. In consideration of fatigue stress constraint, the fuzzy multi-objectives topology optimization of frame was conducted through OptiStruct solver. The results showed that the stiffness of optimized frame under forward torsion and post torsion and full torsion conditions was improved by 4.7 %, 7.4 % and 5.4 %, respectively, while the stiffness of optimized frame under bending condition was worsened by 2.7 %. The first order natural frequency of optimized frame was improved by 5.6 %.

Optimization-based Image Watermarking Algorithm Using a Maximum-Likelihood Decoding Scheme in the Complex Wavelet Domain

( Jinhua Liu ),( Yunbo Rao ) 한국인터넷정보학회 2019 KSII Transactions on Internet and Information Syst Vol.13 No.1

Most existing wavelet-based multiplicative watermarking methods are affected by geometric attacks to a certain extent. A serious limitation of wavelet-based multiplicative watermarking is its sensitivity to rotation, scaling, and translation. In this study, we propose an image watermarking method by using dual-tree complex wavelet transform with a multi-objective optimization approach. We embed the watermark information into an image region with a high entropy value via a multiplicative strategy. The major contribution of this work is that the trade-off between imperceptibility and robustness is simply solved by using the multi-objective optimization approach, which applies the watermark error probability and an image quality metric to establish a multi-objective optimization function. In this manner, the optimal embedding factor obtained by solving the multi-objective function effectively controls watermark strength. For watermark decoding, we adopt a maximum likelihood decision criterion. Finally, we evaluate the performance of the proposed method by conducting simulations on benchmark test images. Experiment results demonstrate the imperceptibility of the proposed method and its robustness against various attacks, including additive white Gaussian noise, JPEG compression, scaling, rotation, and combined attacks.

A fractal model for predicting thermal contact conductance considering elasto-plastic deformation and base thermal resistances

JinHua Zhang,Yili Liu,Ke Yan,Bin Fang 대한기계학회 2019 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.33 No.1

A prediction model of thermal contact conductance is developed. Engineering rough surfaces are characterized by three-dimensional fractal Weierstrass-Mandelbrot fractal function. Three deformation modes, including fully plastic deformation, elasto-plastic deformation and elastic deformation, are considered to analyze the contact mechanism. Fractal surface and three deformation modes are incorporated into the calculation of thermal contact conductance. A comprehensive thermal contact conductance computation model considering both base thermal resistance and constricted thermal resistance is established. The results show that thermal contact conductance increases with the increase of normal contact pressure; the relative contribution of constricted resistance component to base resistance component tends to increase with the increase of normal contact pressure; fractal dimension and fractal roughness both have significant influences on thermal contact conductance.

Simultaneous Electrochemical Determination of Hydroquinone, Catechol and Resorcinol at Nitrogen Doped Porous Carbon Nanopolyhedrons-multiwall Carbon Nanotubes Hybrid Materials Modified Glassy Carbon Electrode

Liu, Wei,Wu, Liang,Zhang, Xiaohua,Chen, Jinhua Korean Chemical Society 2014 Bulletin of the Korean Chemical Society Vol.35 No.1

The nitrogen doped porous carbon nanopolyhedrons (N-PCNPs)-multi-walled carbon nanotubes (MWCNTs) hybrid materials were prepared for the first time. Combining the excellent catalytic activities, good electrical conductivities and high surface areas of N-PCNPs and MWCNTs, the simultaneous determination of hydroquinone (HQ), catechol (CC) and resorcinol (RE) with good analytical performance was achieved at the N-PCNPs-MWCNTs modified electrode. The linear response ranges for HQ, CC and RE are 0.2-455 ${\mu}M$, 0.7-440 ${\mu}M$ and 3.0-365 ${\mu}M$, respectively, and the detection limits (S/N = 3) are $0.03{\mu}M$, $0.11{\mu}M$ and $0.38{\mu}M$, respectively. These results are much better than that obtained on some graphene or CNTs-based materials modified electrodes. Furthermore, the developed sensor was successfully applied to simultaneously detect HQ, CC and RE in the local river water samples.

The Construction of the Heterostructural Bi2O3/g-C3N4 Composites with an Enhanced Photocatalytic Activity

Jinhua Zhang,Huiyue Qian,Wencheng Liu,Hao Chen,Yang Qu,Zhidong Lin 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2018 NANO Vol.13 No.6

A heterostructural composite composed of g-C3N4 and Bi2O3 was achieved by the one-pot and thermal-induced polycondensation method using melamine and Bi(NO3)3 as precursor at 550 ℃ under air atmosphere. The crystalline phase, components and morphologies of the as-prepared composites were investigated by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), X-ray photoelectron spectroscopy (XPS) and transmission electron microscopy (TEM). Besides, the photocatalytic activity of composites was evaluated by degrading RhB aqueous solution at room temperature under visible light irradiation. Compared with bulk g-C3N4, the photocatalytic efficiency of the 0.5% Bi2O3/g-C3N4 (Bi–CN) was increased by up to four times. The introduction of Bi2O3 enhances not only the light absorption ability, but also the separation of photogenerated electron–hole pairs.

Identification of Moment of Inertia for PMSM Using Improved Model-reference Adaptive System

Jinhua She,Lulu Wu,Chuan-Ke Zhang,Zhen-Tao Liu,Yonghua Xiong 제어·로봇·시스템학회 2022 International Journal of Control, Automation, and Vol.20 No.1

The moment of inertia (MOI) is one of the most important parameters of a permanent magnet synchronous motor. High-precision identification of the MOI is essential to ensure system performance. This paper explains an MOI identification method based on the frame of an improved model-reference adaptive system (IMRAS). It improved a model-reference adaptive system by incorporating a curvature model and a dynamic gain in the system. First, a curvature model is used to estimate a load torque to construct an accurate reference model. This strategy reduces the identification error caused by ignoring the load torque. Note that identification accuracy and convergence speed are closely related to a gain factor in the system. Then, the relationship between the gain factor and the convergence time of the identification error is modeled as a power function. Finally, the IMRAS uses the absolute value of the relative MOI error and the convergence time for a given gain factor as switching conditions to balance the convergence speed and identification accuracy. A comparison with a conventional fixed-gain MRAS shows the effectiveness and superiority of the developed method.

Simultaneous Electrochemical Determination of Hydroquinone, Catechol and Resorcinol at Nitrogen Doped Porous Carbon Nanopolyhedrons-multiwall Carbon Nanotubes Hybrid Materials Modified Glassy Carbon Electrode

Wei Liu,Liang Wu,Xiaohua Zhang,Jinhua Chen 대한화학회 2014 Bulletin of the Korean Chemical Society Vol.35 No.1

The nitrogen doped porous carbon nanopolyhedrons (N-PCNPs)-multi-walled carbon nanotubes (MWCNTs) hybrid materials were prepared for the first time. Combining the excellent catalytic activities, good electrical conductivities and high surface areas of N-PCNPs and MWCNTs, the simultaneous determination of hydroquinone (HQ), catechol (CC) and resorcinol (RE) with good analytical performance was achieved at the NPCNPs- MWCNTs modified electrode. The linear response ranges for HQ, CC and RE are 0.2-455 μM, 0.7- 440 μM and 3.0-365 μM, respectively, and the detection limits (S/N = 3) are 0.03 μM, 0.11 μM and 0.38 μM, respectively. These results are much better than that obtained on some graphene or CNTs-based materials modified electrodes. Furthermore, the developed sensor was successfully applied to simultaneously detect HQ, CC and RE in the local river water samples.

Genetic diversity analysis in Chinese miniature pigs using swine leukocyte antigen complex microsatellites

Wu, Jinhua,Liu, Ronghui,Li, Hua,Yu, Hui,Yang, Yalan Asian Australasian Association of Animal Productio 2021 Animal Bioscience Vol.34 No.11

Objective: The swine leukocyte antigen (SLA) gene group, which is closely linked and highly polymorphic, has important biomedical significance in the protection and utilization of germplasm resources. However, genetic polymorphism analyses of SLA microsatellite markers in Chinese miniature pigs are limited. Methods: Eighteen pairs of microsatellite primers were used to amplify the SLA regions of seven miniature pig breeds and three wild boar breeds (n = 346) from different regions of China. The indexes of genetic polymorphism, including expected heterozygosity (He), polymorphic information content (PIC), and haplotype, were analyzed. The genetic differentiation coefficient (Fst) and neighbor-joining methods were used for cluster analysis of the breeds. Results: In miniature pigs, the SLA I region had the highest numbers of polymorphisms, followed by the SLA II and SLA III regions; the region near the centromere had the lowest number of polymorphisms. Among the seven miniature pig breeds, Diannan small-ear pigs had the highest genetic diversity (PIC value = 0.6396), whereas the genetic diversity of the Hebao pig was the lowest (PIC value = 0.4330). The Fst values in the Mingguang small-ear, Diannan small-ear, and Yunnan wild boars were less than 0.05. According to phylogenetic cluster analysis, the South-China-type miniature pigs clustered into one group, among which Mingguang small-ear pigs clustered with Diannan small-ear pigs. Haplotype analysis revealed that the SLA I, II, and III regions could be constructed into 13, 7, and 11 common haplotypes, respectively. Conclusion: This study validates the high genetic diversity of the Chinese miniature pig. Mingguang small-ear pigs have close kinship with Diannan small-ear pigs, implying that they may have similar genetic backgrounds and originate from the same population. This study also provides a foundation for genetic breeding, genetic resource protection, and classification of Chinese miniature pigs.

Preparation and Properties of HUHPC with Low Shrinkage and High Impact Resistance

Qingjun Ding,Jinhua Gong,Gaozhan Zhang,Yang Liu,Jun Yang,Yongyuan Zhang,Peng Zhou 대한토목학회 2023 KSCE Journal of Civil Engineering Vol.27 No.8

At present, nuclear energy is widely used to reduce pollution and clean energy. However, the radiation-proof concrete currently used to prepare nuclear shields cannot meet the protection requirements of nuclear safety. Therefore, there is an urgent need to develop radiation-proof concrete materials with high impact resistance and ultra-high strength. In this paper, the low-shrinkage, high-impact Heavy Ultra-High-Performance Concrete (HUHPC) was designed by the following innovative methods: Porous high titanium heavy slag sand (HTHS) (industrial solid waste) with “slow-water release” effect and expansion agent were synergistically used to improve volume stability; Irregular HTHS with “embedded lock” effect and steel fibers were synergistically utilized to enhance impact resistance; Heavy ilmenite sand was used to lift volume weight. The workability, mechanical properties, volume stability, impact resistance, and microstructure were studied. The results show that the designed HUHPC volume weight is more than 2,800 kg/m3 which can enhance the radiation protection performance greatly. The 180 d shrinkage of HUHPC is less than 400 με, which volume stability is improved by more than 30%. The addition of lithium carbonate slightly decreased the 28 d strength of HUHPC, but the appropriate admixture amount (0.9%) could improve the impact resistance of HUHPC by 33%.

Application of molecular dynamics simulation in self-assembled cancer nanomedicine

Xueli Xu,Ao Liu,Shuangqing Liu,Yanling Ma,Xinyu Zhang,Meng Zhang,Jinhua Zhao,Shuo Sun,Xiao Sun 한국생체재료학회 2023 생체재료학회지 Vol.27 No.00

Self-assembled nanomedicine holds great potential in cancer theragnostic. The structures and dynamics of nanomedicine can be affected by a variety of non-covalent interactions, so it is essential to ensure the self-assembly process at atomic level. Molecular dynamics (MD) simulation is a key technology to link microcosm and macroscale. Along with the rapid development of computational power and simulation methods, scientists could simulate the specific process of intermolecular interactions. Thus, some experimental observations could be explained at microscopic level and the nanomedicine synthesis process would have traces to follow. This review not only outlines the concept, basic principle, and the parameter setting of MD simulation, but also highlights the recent progress in MD simulation for self-assembled cancer nanomedicine. In addition, the physicochemical parameters of self-assembly structure and interaction between various assembled molecules under MD simulation are also discussed. Therefore, this review will help advanced and novice researchers to quickly zoom in on fundamental information and gather some thoughtprovoking ideas to advance this subfield of self-assembled cancer nanomedicine.