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      • KCI등재

        Amino ionic liquids-modified magnetic core/shell nanocomposite as an efficient adsorbent for dye removal

        Jingjing Cheng,Lijuan Shi,Jianjun Lu 한국공업화학회 2016 Journal of Industrial and Engineering Chemistry Vol.36 No.-

        Amino ionic liquids modified superparamagnetic mesoporous core/shell nanocomposite (Fe3O4@n-SiO2@mSiO2@DHIM-NH2) was synthesized to remove orange II and amaranth from water. Due to themultiple active sites of the introduced ionic liquids, the adsorbent presents superior adsorptionperformance and instantaneous adsorption capacity. The maximum adsorption capacities are reached atpH 2 due to the protonation of amino groups, which are 153.06 and 84.40 mg g 1 for orange II andamaranth, respectively. The good stability, rapid adsorption kinetics, large adsorption capacity, and highseparation efficiency make Fe3O4@nSiO2@mSiO2@DHIM-NH2 an efficient adsorbent for removinganionic contaminant from water.

      • SCIESCOPUS

        Refined numerical simulation in wind resource assessment

        Cheng, Xue-Ling,Li, Jun,Hu, Fei,Xu, Jingjing,Zhu, Rong Techno-Press 2015 Wind and Structures, An International Journal (WAS Vol.20 No.1

        A coupled model system for Wind Resource Assessment (WRA) was studied. Using a mesoscale meteorological model, the Weather Research and Forecasting (WRF) model, global-scale data were downscaled to the inner nested grid scale (typically a few kilometers), and then through the coupling Computational Fluid Dynamics (CFD) mode, FLUENT. High-resolution results (50 m in the horizontal direction; 10 m in the vertical direction below 150 m) of the wind speed distribution data and ultimately refined wind farm information, were obtained. The refined WRF/FLUENT system was then applied to assess the wind resource over complex terrain in the northern Poyang Lake region. The results showed that the approach is viable for the assessment of wind energy.

      • KCI등재

        A Path Optimization Technique with Obstacle Avoidance for an 8-DOF Robot in Bolt Looseness Detection Task

        Jingjing Xu,Zhifeng Liu,Yongsheng Zhao,Yanhu Pei,Qiang Cheng 한국정밀공학회 2019 International Journal of Precision Engineering and Vol.20 No.5

        In the bolt looseness detection task of the locomotive system, the robot could be used to highly improve the working efficiency and reliability, but faces the complex static obstacles while planning the path for the robotic motion. In this paper, a path optimization technique is proposed to obtain an optimal path with obstacle avoidance for a redundant robot in the static complicated environment. There are three main contributions in this technique. The first is the solving of the inverse kinematics problem for a redundant robot based on the screw theory and the geometric description, which is general to all robots with rotational joints. The second is the modeling of the spatial constraint, where the pseudo distance is defined based on the plane description of the obstacles and calculated using the spatial analytic geometry knowledge. The third is the presentation of the whole path-planning framework based on the above two contributions, which could largely improve the generality of the presented technique. In this framework, the minimum-time path could be obtained while guaranteeing both the motion stability and obstacle avoidance. Moreover, a real setting that includes an obstacle environment and an 8-DOF robot, is taken as an example to better present the technique. Finally, the simulation experiment was performed in Isight software to verify the effectiveness of the path optimization technique.

      • THE RESEARCH OF THE INFLUENCE OF ENVIRONMENTAL VALUES ON THE GREEN CONSUMER BEHAVIOR

        Qiaolian Cheng,Kexin Liu,,Ruijin Zhang,Guofeng Li,Jingjing Wang 글로벌지식마케팅경영학회 2016 Global Marketing Conference Vol.2016 No.7

        There may be not direct path from the psychological selection by the customers to the green behavior owing to the complexity of the green consumption. The specific mode of action still needs being further researched. This paper will research the specific path and mechanism of customer’s green consumption based on VBN theory. Based on a survey of Chinese respondents, environment values bring indirect influence to green customer behavior through individual belief or subjective norm intermediately. However, there are different paths from value to behavior. One path is that egoistic value-subjective norm-green customer behavior while another path is that altruistic value-environment beliefs-subjective norm-green customer behavior which really fits into previous research of VBN theory.

      • KCI등재

        Trajectory Planning with Minimum Synthesis Error for Industrial Robots Using Screw Theory

        Zhifeng Liu,Jingjing Xu,Qiang Cheng,Yongsheng Zhao,Yanhu Pei,Congbin Yang 한국정밀공학회 2018 International Journal of Precision Engineering and Vol.19 No.2

        This work aims to propose a trajectory planning technique to minimize the end-effector synthesis error for industrial robots, while obtaining a stable movement. With ER3A-C60 robot as a research subject, the kinematic and dynamic models are established by using screw theory and Kane equations, and based on that, the end-effector synthesis error is modeled by considering the effects of interpolation algorithm and flexibilities of all joints. The septic polynomial is used to interpolate the via points in each joint space to obtain a stable movement. Finally, the PSO algorithm with suitable parameters is applied to find the minimum synthesis error under kinematic and dynamic constraints. The results show that the optimal synthesis error decreases by 88.94% compared with the initial one, the angular parameters are all far less than the limitations of joints and the optimal movement has a high stability, and this optimal trajectory has better overall performance than that based on the previous technique (with the minimum total motion time). The main contribution is that the proposed trajectory planning technique can significantly improve the tracking precision of the end effector while controlling the motion time within a given span under the requirements of continuous path control.

      • KCI등재

        Contact Stiffness Determination of High-Speed Double- Locking Toolholder-Spindle Joint based on a Macro- Micro Scale Hybrid Method

        Yongsheng Zhao,Jingjing Xu,Ligang Cai,Weimin Shi,Zhifeng Liu,Qiang Cheng 한국정밀공학회 2016 International Journal of Precision Engineering and Vol.17 No.6

        The stiffness of toolholder-spindle joint at high speeds plays an important role in the cutting efficiency and the machining accuracy. A double-locking toolholder (BTF type) is designed to improve the stiffness of joint. This paper presents a macro-micro scale hybrid method to determine the stiffness of double-locking toolholder-spindle joint at high speeds. In this method the finite element method and the three-dimensional fractal method are combined. It is assumed flat in macro-scale for the contact surfaces of joint. The finite element method is introduced to obtain the pressure distribution with the influence of centrifugal force at high speeds. In micro-scale, the contact surfaces are fractal featured and the three-dimensional fractal method is used to compute the stiffness based on the pressure. Experiments with BTF40-type toolholder are conducted to verify the efficiency of the proposed model in zero-speed case. The relationship between the stiffness and the technological parameters of the system can be derived based on the presented model. The upper limit of speed, the optimized range of each technological parameter are determined for obtaining the higher stiffness of joint. The results can provide theoretical basis for improving the cutting efficiency and the machining accuracy of high-speed machine tool.

      • KCI등재

        Refined numerical simulation in wind resource assessment

        Xue-Ling Cheng,Jun Li,Fei Hu,Jingjing Xu,Rong Zhu 한국풍공학회 2015 Wind and Structures, An International Journal (WAS Vol.20 No.1

        A coupled model system for Wind Resource Assessment (WRA) was studied. Using a mesoscale meteorological model, the Weather Research and Forecasting (WRF) model, global-scale data were downscaled to the inner nested grid scale (typically a few kilometers), and then through the coupling Computational Fluid Dynamics (CFD) mode, FLUENT. High-resolution results (50 m in the horizontal direction; 10 m in the vertical direction below 150 m) of the wind speed distribution data and ultimately refined wind farm information, were obtained. The refined WRF/FLUENT system was then applied to assess the wind resource over complex terrain in the northern Poyang Lake region. The results showed that the approach is viable for the assessment of wind energy.

      • KCI등재

        Joint module angle error analysis and modelling of self-driven articulated arm coordinate measuring machine

        Mei Shen,Hongtao Yang,Jingjing Cheng,Mengyao Zhang,Tingting Hu,Yi Hu 대한기계학회 2022 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.36 No.12

        The self-driven articulated arm coordinate measuring machine (self-driven AACMM) is a new type of flexible coordinate measuring equipment. The integrated joint module is introduced to the AACMM joint for self-driven control and automatic measurement, resulting in the joint angle error of self-driven AACMM. In this study, an ideal measurement model of the self-driven AACMM have been established. The sources of angle error of joint module is analysed, and single and comprehensive models of the joint module‘s angle error are established. Numerical simulation of the angle error model of the single joint module is conducted by MATLAB. An angle error calibration experiment of the joint module is carried out with the photoelectric autocollimator and the metal 36-sided prism. Results show that each joint module produces different torsional deformation due to load. The angle error of joint module 1, 6 are most and least affected by the load torque, the actual average errors of the two are 37.64 arcsec and -0.9632 arcsec, respectively. The simulated and calibrated single-joint module angle error trends are cyclical, and the calibrated angle error range is [-100.4 arcsec, 205.2 arcsec]. The harmonic error component in the harmonic reducer and the magnetic encoder is an important factor of the angle error of joint module. The eatablished angle error model of single joint module can be effiectively applied to comprehensive error compensation for high measurement accuracy of self-driven AACMM.

      • KCI등재

        Outcomes of epidural steroids following percutaneous transforaminal endoscopic discectomy: a meta-analysis and systematic review

        Yinghao Song,Changxi Li,Jingjing Guan,Cheng Li,Haisheng Wu,Xinzhi Cheng,Bingyu Ling,Jinglang Zhang 대한통증학회 2022 The Korean Journal of Pain Vol.35 No.1

        Background: Percutaneous transforaminal endoscopic discectomy (PTED) has been widely used in the treatment of lumbar degenerative diseases. Epidural injection of steroids can reduce the incidence and duration of postoperative pain in a short period of time. Although steroids are widely believed to reduce the effect of surgical trauma, the observation indicators are not uniform, especially the long-term effects, so the problem remains controversial. Therefore, the purpose of this paper was to evaluate the efficacy of epidural steroids following PTED. Methods: We searched PubMed, Embase, and the Cochrane Database from 1980 to June 2021 to identify randomized and non-randomized controlled trials comparing epidural steroids and saline alone following PTED. The primary outcomes included postoperative pain at least 6 months as assessed using a visual analogue scale (VAS) and the Oswestry Disability Index (ODI). The secondary outcomes included length of hospital stay and the time of return to work. Results: A total of 451 patients were included in three randomized and two nonrandomized controlled trials. The primary outcomes, including VAS and ODI scores, did not differ significantly between epidural steroids following PTED and saline alone. There were no significant intergroup differences in length of hospital stay. Epidural steroids were shown to be superior in terms of the time to return to work (P < 0.001). Conclusions: Intraoperative epidural steroids did not provide significant benefits, leg pain control, improvement in ODI scores, and length of stay in the hospital, but it can enable the patient to return to work faster.

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