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| 1 | Contourlet HMT model with directional feature显示文摘According to Shanno's information theory,the directional feature of texture is defined as the value of directional variable when an image signal attains a singularity of random distribution.In terms of this definition,we calculate the texture's directional features using Tamura's method and study the directional probability distribution of Contourlet coefficients.Then we find that the directional features tend to be conveyed across parent and child subbands.Based on this conclusion,we establish a novel probability distribution model of hidden direction variables under the condition of hidden state variable's distribution,named Contourlet HMT model with directional feature.The structure and training method of the model are presented as well.Moreover,an unsupervised context-based image segmentation algorithm is proposed on the basis of the proposed model.Its effectiveness is verified via extensive experiments carried out on several synthesized images and remote sensing images. | WANG XiangHai CHEN MingYing SONG ChuanMing XU MengChun FANG LingLing | 2012 | Science China(Information Sciences)2012，55，7： | 6 |
| 2 | Resonance Suppression Strategy for Humanoid Robot Arm显示文摘To address the problem of resonance in the control of a robot arm,a resonance suppression strategy is proposed for a single-joint humanoid robot arm based on the proportionalresonant(PR)controller.First,an arm joint model of the humanoid robot is established.Then the influence of resonance frequency on the performance of the control system with the robot arm is analyzed.The voltage fluctuation of the drive motor caused by the changes in arm motion is recognized as the disturbance of the current loop.The PR controller has the characteristic of disturbance rejection at a specific frequency.The output fluctuation of the driving system caused by the change of arm motion state at the resonance frequency is suppressed.Therefore the output current of the inverter will not be affected by the vibration of the arm at the resonance frequency.Finally,the control system is verified by MATLAB/Simulink simulation.The simulation results demonstrate that the control strategy for the humanoid robot arm based on the PR controller can suppress the resonance of the arm effectively,improving the dynamic performance and system stability. | Weiling Zhang Qinjun Du Zhengyang Zhao Chuanming Song Wei Ding Yonggang Luo | 2020 | Journal of Beijing Institute of Technology2020，29，4： | 1 |
| 3 | SHRIMP zircon U–Pb age constraints on Neoproterozoic Quruqtagh diamictites in NW China显示文摘 | Bei Xu Shuhai Xiao Haibo Zou Yan Chen Zheng-Xiang Li Biao Song Dunyi Liu Chuanming Zhou Xunlai Yuan | 2008 | Precambrian Research2008，，3： | 1 |
| 4 | Microwave drying performance of single-particle coal slime and energy consumption analyses显示文摘 | Zhanlong Song Chuanming Jing Liansheng Yao | 2016 | Fuel Processing Technology2016，，143： | 1 |
| 5 | Anti-Windup Control Strategy of Drive System for Humanoid Robot Arm Joint显示文摘To address the problems of torque limit and controller saturation in the control of robot arm joint,an anti-windup control strategy is proposed for a humanoid robot arm,which is based on the integral state prediction under the direct torque control system of brushless DC motor. First,the arm joint of the humanoid robot is modelled. Then the speed controller model and the influence of the initial value of the integral element on the system are analyzed. On the basis of the traditional antiwindup controller,an integral state estimator is set up. Under the condition of different load torques and the given speed,the integral steady-state value is estimated. Therefore the accumulation of the speed error terminates when the integrator reaches saturation. Then the predicted integral steady-state value is used as the initial value of the regulator to enter the linear region to make the system achieve the purpose of anti-windup. The simulation results demonstrate that the control strategy for the humanoid robot arm joint based on integral state prediction can play the role of anti-windup and suppress the overshoot of the system effectively. The system has a good dynamic performance. | Xiaofei Zhang Qinjun Du Chuanming Song Yi Cheng | 2018 | Journal of Beijing Institute of Technology2018，27，2： | 0 |
| 6 | Prediction and cause investigation of ozone based on a double-stage attention mechanism recurrent neural network显示文摘Ozone is becoming a significant air pollutant in some regions,and VOCs are essential for ozone prediction as necessary ozone precursors.In this study,we proposed a recurrent neural network based on a double-stage attention mechanism model to predict ozone,selected an appropriate time series for prediction through the input attention and temporal attention mechanisms,and analyzed the cause of ozone generation according to the contribution of feature parameters.The experimental data show that our model had an RMSE of 7.71μg/m3 and a mean absolute error of 5.97μg/m3 for 1-h predictions.The DA-RNN model predicted ozone closer to observations than the other models.Based on the importance of the characteristics,we found that the ozone pollution in the Jinshan Industrial Zone mainly comes from the emissions of petrochemical enterprises,and the good generalization performance of the model is proved through testing multiple stations.Our experimental results demonstrate the validity and promising application of the DA-RNN model in predicting atmospheric pollutants and investigating their causes. | Yuanxin Zhang Fei Li Chaoqiong Ni Song Gao Shuwei Zhang Jin Xue Zhukai Ning Chuanming Wei Fang Fang Yongyou Nie Zheng Jiao | 2023 | Frontiers of Environmental Science & Engineering2023，17，2： | 0 |
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