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1

An adaptive estimation of ground vehicle state with unknown measurement noise

Wang Yan, Sun Xuan, Cui Dong, Wang Xianfang, Jia Zhijuan, Zhang Zhiguo

Metrology and Measurement Systems

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2024

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Vol. 31, nr 2

383--399

EN

Accurate information about the vehicle state such as sideslip angle is critical for both advanced assisted driving systems and driverless driving. These vehicle states are used for active safety control and motion planning of the vehicle. Since these state parameters cannot be directly measured by onboard sensors, this paper proposes an adaptive estimation scheme in case of unknown measurement noise. Firstly, an estimation method based on the bicycle model is established using a square-root cubature Kalman filter (SQCKF), and secondly, the expectation maximization (EM) approach is used to dynamically update the statistic parameters of measurement noise and integrate it into SQCKF to form a new expectation maximization square-root cubature Kalman filter (EMSQCKF) algorithm. Simulations and experiments show that EMSQCKF has higher estimation accuracy under different driving conditions compared to the unscented Kalman filter.

2

Application and Parametric Design of Line Visual Illusion Graphics in Clothing

Zou Yixin, Wang Yan, Luh Ding-Bang

Fibres & Textiles in Eastern Europe

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2023

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Vol. 31, no. 2

65--74

EN

This research adopted literature analysis methods to explain the principles and types of line illusion and, secondly, using Grasshopper software generated some fashion design samples with visual illusion element application. Then semantic analysis was applied to investigate audiences’ cognition, with the aim to improve the design. Lastly, Grasshopper software was used to generate new design patterns by changing the set of generated points through algorithm operation and dotted line interference to change the presented linear illusion forms and patterns. The results of this research show that with the support of parametric technology, the opportunities and space for creating line elements in clothing will be further expanded, enabling that real-time pattern or apparel design changes, and adjustments can be realized by parameter variable controlling. The research comprised a new attempt at combining linear visual illusion, fashion design and parametric design, showing the content and design case studies for relevant research in this area.

3

SSD-based carton packaging quality defect detection system for the logistics supply chain

Song Bing, Wang Yan, Lou Li-Ping

Ecological Chemistry and Engineering. S

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2023

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Vol. 30, nr 1

117--123

EN

With the deepening of green and sustainable development and the rapid development of the social economy, the modern logistics industry has also developed to an unprecedented level. In the logistics supply chain, due to the high value of the items inside the arrival carton, appearance inspection must be carried out before warehousing. However, manual inspection is slow and ineffective, resulting in the waste of manpower and packaging carton resources, which is not conducive to sustainable development. To address the above problems, this paper designs a logistics supply chain carton packaging quality defect detection system based on improved Single Shot MultiBox Detector (SSD) in the context of green sustainable development. The Implicit Feature Pyramid Network (IFPN) is introduced into SSD to improve the feature extraction ability of the model; the multiscale attention mechanism is introduced to collect more feature information. The experiment shows that the mAP and FPS of the system on the self-built data set reach 0.9662 and 36 respectively, which can realise the detection of the appearance defects of logistics cartons and help promote green sustainable development.

4

Seismic behavior of interior polyvinyl chloride-carbon fiber-reinforced polymer-confined concrete column-ring beam joints

Yu Feng, Wang Shisi, Fang Yuan, Zhang Nannan, Wang Yan, Nuermaimaiti Maimaiti

Archives of Civil and Mechanical Engineering

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2023

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Vol. 23, no. 1

art. no. e49, 2023

EN

Eleven interior polyvinyl chloride (PVC)-carbon fiber-reinforced polymer (CFRP)-confined concrete (PCCC) column-ring beam joints are fabricated and experimentally investigated. The impacts of axial compression ratio, frame beam reinforcement ratio, CFRP strips spacing, ring beam width and ring beam reinforcement ratio, on seismic behaviors are analyzed. All specimens show obvious failure signs, and the frame beam reinforcement ratio exerts a degree of effect on failure positions, exhibiting different failure modes, such as shear failure in the joint zone, shear-bending failure at the junction and bending failure at the frame beam. The experimental results show that the hysteresis curves are relatively full, which have roughly experienced four stages as elastic, elastic-plastic, stable and decline stages, reflecting that the interior joints have considerable seismic behavior. The increment of ring beam reinforcement ratio or ring beam width enhances the load capacity, mitigates degradation of strength and stiffness. The peak load increases by 38.63% as the ring beam reinforcement ratio increases from 0.88 to 1.5%. When the ring beam width increases from 75 to 125 mm, the peak load increases by 37.24%. Appropriately increasing axial compression ratio can raise the load capacity, alleviate strength degradation, and enhance the initial stiffness. As the axial compression ratio increases from 0.2 to 0.4, the peak load increases by19.41%. The joints with larger frame beam reinforcement ratio show higher load capacity, while the frame beam reinforcement ratio exerts marginal impacts on strength and initial stiffness degradation. The existing classical shear models and specification design formulae are used to evaluate the shear capacity of the interior joints, and the reasons for the deviations of prediction results are expounded, which provides the theoretical basis and useful reference for the subsequent establishment of a new shear capacity formula of the joints.

5

Shear behavior and design of an innovative embedded connector with flange for steel–concrete composite girder

Zhang Zhe, Zhang Sheng-Nan, Deng En-Feng, Yu Chen-Yang, Tang Yi, Wang Yan, Sun Dong-Sheng

Archives of Civil and Mechanical Engineering

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2022

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Vol. 22, no. 4

art. no. e195, 2022

EN

Connectors are crucial for steel–concrete composite girder to insure cooperative work of the two different materials. Flanges in connectors can be used as supports and templates to accelerate construction progress. Embedded connector is a type of connector formed by embedded web with opening holes for arranging reinforcements. However, traditional embedded connector does not include flanges. In this paper, an embedded connector with flanges was proposed. Three full-scale specimens were fabricated and push-out tests were conducted to investigate the shear behavior of the innovative connector. The failure mode and shear performance of the traditional embedded shear connector without flanges and the innovative connector with flanges were compared. Three-dimensional finite-element model (FEM) was developed and validated based on the test results. Furthermore, parametric analysis was conducted to further study the effects of the strength of the concrete, diameter of the hole, diameter of the perforating rebar, embedding depth, and height of the corrugated web on the shear performance of the innovative connector. The results of the parametric study were analyzed to evaluate the shear capacity for the embedded connector with flanges. Finally, an analytical model was proposed to predict the shear strength of the innovative embedded connector, which will provide important guidance for engineering application.

6

Feasible brittleness evaluation method and suggestion for brittleness reduction of cementitious materials based on stress–strain curve

Fu Qiang, Wang Zhenhua, Zhou Zhiming, Niu Ditao, Wang Yan

Archives of Civil and Mechanical Engineering

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2022

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Vol. 22, no. 4

art. no. e209, 2022

EN

In this study, a brittleness evaluation index B5 and brittleness–plasticity classification standard for cementitious materials were established, and a suggestion for brittleness reduction was proposed. The results showed that B5 established based on the principle of energy conversion can effectively characterize the variation in the brittleness of cementitious materials with the confining pressure, and the brittleness order of different cementitious materials. Based on the established brittleness–plasticity classification standard, the ranges of B5 corresponding to the weak, high and ideal brittleness are [0.3, 0.6), [0.6, 1) and 1, respectively; and those corresponding to the weak, high and ideal plasticity are [0.1, 0.3), (0, 0.1) and 0, respectively. Finally, a suggestion for brittleness reduction using prismatic aggregates and hybrid nanofibers, flexible and rigid fibers of different sizes was proposed, and the corresponding design process of cementitious materials with weak brittleness was given. The research results in this study provide a basis for the brittleness evaluation of cementitious materials and the design of cementitious materials with weak brittleness.

7

Strengthening the rough selection effect of n-ethyl o-isopropyl thionocarbamate (Dow: Z-200) on chalcopyrite by ultrasonic pretreatment

Wang Yan, Wang Yubin, Yu Bo, Wang Xin, Ma Xiaoxiao

Physicochemical Problems of Mineral Processing

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2021

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Vol. 57, iss. 1

64--74

EN

In this study, the properties of (CH3)2CHOC(S)NHC2H5(Dow: Z-200) after the ultrasonic pretreatment was characterized by employing surface tension, viscosity, and Fourier transform infrared (FTIR) spectroscopy, and its influence on chalcopyrite rough selecting was investigated. The results indicate that the pretreated Z-200 can improve the index of chalcopyrite roughing. And, under the same reagent system, the recovery of copper reached 82.84% which was an increase of 24.44% compared with the untreated when Z-200 after ultrasonic pretreatment was applied to the rough separation of chalcopyrite. The reason why ultrasonic can strengthen the flotation effect of Z-200 on chalcopyrite is that ultrasonic pretreatment can decrease the surface tension and viscosity of Z-200 and enhance its foaming performance. Meanwhile, the ultrasonic cavitation destroys the molecular structure of Z-200, so that the relative proportion of methyl absorption peak and amine absorption peak in Z-200 increases. This also further improves the collection performance and foaming performance of Z-200 and strengthens its separation effect on chalcopyrite. The research provides a new idea for Z-200 to act on chalcopyrite and improve its flotation efficiency, reduce the amount of flotation reagent, and its pollution to the environment. It also provides a theoretical basis for expanding the application of ultrasonic technology in the field of flotation.

8

CFD simulation on wind turbine blades with leading edge erosion

Wang Yan, Wang Liang, Duan Chenglin, Zheng Jian, Liu Zhe, Ma Gaosheng

Journal of Theoretical and Applied Mechanics

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2021

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Vol. 59 nr 4

579--593

EN

Deep understanding on the impacts of leading edge erosion on the performance and flow characteristics of wind turbines is significant for the blade design and wind farms manage- ment. Pitting erosion and three levels of delamination are considered in the present study. The results show that the degrees of leading edge erosion have great influence on the flow separation, tangential force coefficient, normal force coefficient as well as the power output of the wind turbine. Leading edge erosion has the greatest impact on aerodynamics of the wind turbine at 15m/s, where the maximum loss in the power output can reach up to 73.26%.

9

Effect of Temperature on the Structure and Filtration Performance of Polypropylene Melt-Blown Nonwovens

Cheng Si, Muhaiminul Alam S. M., Yue Zhonghua, Wang Yan, Xiao Yuanxiang, Militky Jiri, Prasad Mohanapriya, Zhu Guocheng

Autex Research Journal

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2021

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Vol. 21, no. 2

207--217

EN

By applying the simultaneous corona-temperature treatment, the effect of electret temperature on the structure and filtration properties of melt-blown nonwovens was investigated. Fiber diameter, pore size, thickness, areal weight, porosity, crystallinity, filtration efficiency, and pressure drop were evaluated. The results demonstrated that some changes occurred in the structure of electret fabrics after treatment under different temperatures. In the range of 20°C~105°C, the filtration efficiency of melt-blown nonwovens has a relationship with the change in crystallinity, and the pressure drop increased because of the change in areal weight and porosity. This work may provide a reference for further improving filtration efficiency of melt-blown nonwovens.

10

Evaluation of integrated UFCW-MFC reactor for azo dye wastewater treatment and simultaneous bioelectricity generation

Zou Haiming, Chu Lin, Wang Yan

Environment Protection Engineering

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2020

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Vol. 46, nr 1

63--72

EN

An up-flow constructed wetland (UFCW) incorporating a novel membrane-less air-cathode single-chamber microbial fuel cell (MFC) was designed to treat dye wastewater and simultaneously generate bioelectricity. The performance of UFCW-MFC was evaluated via Methyl Orange (MO) and chemical oxygen demand (COD) removal rates and the output voltage. For comparison, the performance of a single UFCW was also assessed. A repeatable and stable voltage output of about 0.44±0.2 V was obtained in UFCW-MFC. The MO and COD removal rates in UFCW-MFC were 93.5 and 57.2%, respectively, significantly higher than those in single UFCW (75.4 and 42.6%, respectively), suggesting the obvious enhancement of electrodes on MO and COD removal. The anode zone of UFCW-MFC made the most contribution to MO and COD removal compared with other layers. The oxidation-reduction potential (ORP) and dissolved oxygen (DO) profiles showed that the anaerobic environment was well developed in the lower part of UFCW-MFC (0–24 cm) and the upper part (41–42 cm) had a good aerobic environment, thus greatly contributing to the MO anaerobic reduction and aerobic degradation of breakdown products. These results obtained here suggest that the UFCW-MFC may provide an effective alternative for the treatment of dye wastewater and simultaneous bioelectricity generation.

11

Study on the Relationship Between Structure Parameters and Filtration Performance of Polypropylene Meltblown Nonwovens

Xiao Yuanxiang, Sakib Nazmus, Yue Zhonghua, Wang Yan, Cheng Si, You Jianmin, Militky Jiri, Venkataraman Mohanapriya, Zhu Guocheng

Autex Research Journal

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2020

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Vol. 20, no. 4

366--371

EN

In this study, polypropylene meltblown nonwoven fabrics with different structure parameters such as fiber diameter, pore size, and areal density were prepared by the industrial production line. The morphology of meltblown nonwoven fibers was evaluated by using scanning electron microscope, and the diameter of fibers was analyzed by using image-pro plus software from at least 200 measurements. The pore size of nonwoven fabric was characterized by a CFP-1500AE type pore size analyzer. The filtration efficiency and pressure drop were evaluated by TSI8130 automatic filter. The results showed that the pressure drop of nonwoven fabrics decreased with the increase in pore size; the filtration efficiency and the pressure drop had a positive correlation with the areal density. However, when the areal density is in the range of 27–29 g/m2, both filtration efficiency and pressure drop decreased with the increase of areal density; when the areal density was kept constant, the filtration efficiency decreased as the pore size decreased; when the pore size of the meltblown nonwoven fabric is less than 17 μm, the filtration efficiency increased as the pore diameter decreased; when the pore diameter of the nonwoven fabric is larger than 17 μm. In a wide range, the pressure drop decreased as the fiber diameter decreased.

12

Performance of Electrospun Polyvinylidene Fluoride Nanofibrous Membrane in Air Filtration

Xiao Yuanxiang, Wen Enlong, Sakib Nazmus, Yue Zhonghua, Wang Yan, Cheng Si, Militky Jiri, Venkataraman Mohanapriya, Zhu Guocheng

Autex Research Journal

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2020

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Vol. 20, no. 4

552--559

EN

Polyvinylidene fluoride (PVDF) fibrous membranes with fiber diameter from nanoscale to microscale were prepared by electrospinning. The structural parameters of PVDF fibrous membrane in terms of fiber diameter, pore size and its distribution, porosity or packing density, thickness, and areal weight were tested. The relationship between solution concentration and structural parameters of fibrous membrane was analyzed. The filtration performance of PVDF fibrous membrane in terms of air permeability and filtration efficiency was evaluated. The results demonstrated that the higher solution concentration led to a larger fiber diameter and higher areal weight of fibrous membrane. However, no regular change was found in thickness, porosity, or pore size of fibrous membrane under different solution concentrations. The air permeability and filtration efficiency of fibrous membrane had positive correlations with pore size. The experimental results of filtration efficiency were compared with the predicted values from current theoretical models based on single fiber filtration efficiency. However, the predicted values did not have a good agreement with experimental results since the fiber diameter was in nanoscale and the ratio of particle size to fiber diameter was much larger than the value that the theoretical model requires.

13

Thermal shock effects on the mechanical behavior of granite exposed to dynamic loading

Li Xiang, Li Baijin, Li Xibing, Yin Tubing, Wang Yan, Dang Wengang

Archives of Civil and Mechanical Engineering

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2020

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Vol. 20, no. 3

30--40

EN

Under certain extreme conditions in rock engineering works, fast change in temperature in the load-bearing rocks can happen. Known as thermal shock (TS), such process involves rapid temperature rise or drop, which causes fracturing in the rock material and thus can pose as a threat to the stability of the rock structures. To investigate the influence of thermal shock caused by fast cooling on the mechanical property of rock, laboratory tests are performed on heated granite which are cooled with different methods, with the highest cooling rate reaching 167.4 °C/min. The dynamic loading tests are performed on the heated granite specimens utilizing the split Hopkinson pressure bar (SHPB) system. The test results show that the dynamic compressive strength drops with the increase in heating level or cooling rate. This pattern is explained by the nuclear magnetic resonance (NMR) test data that the pores inside the heated granite increase both in size and quantity as heating level or cooling rate rises. Damage patterns of the tested granite specimen fragments are analyzed based on the observation with scanning electron microscope (SEM), and the mechanisms of thermal shock in granite are also discussed.

14

Utility optimization-based bandwidth allocation for elastic and inelastic services in peer-to-peer networks

Li Shiyong, Zhang Yue, Wang Yan, Sun Wei

International Journal of Applied Mathematics and Computer Science

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2019

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Vol. 29, no. 1

111--123

EN

This paper considers reasonable bandwidth allocation for multiclass services in peer-to-peer (P2P) networks, measures the satisfaction of each peer as a customer by a utility function when acquiring one service, and develops an optimization model for bandwidth allocation with the objective of utility maximization. Elastic services with concave utilities are first considered and the exact expression of optimal bandwidth allocation for each peer is deduced. In order to obtain an optimum in distributed P2P networks, we develop a gradient-based bandwidth allocation scheme and illustrate the performance with numerical examples. Then we investigate bandwidth allocation for inelastic services with sigmoidal utilities, which is a nonconvex optimization problem. In order to solve it, we analyze provider capacity provisioning for bandwidth allocation of inelastic services and modify the update rule for prices that service customers should pay. Numerical examples are finally given to illustrate that the improved scheme can also efficiently converge to the global optimum.