Tianhao Liu

Tianhao Liu


Research Focus & Metrics

Academic Career Length

6Years (2021-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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8 June 2023 in IEEE Transactions on Neural Networks and Learning Systems
Verified
Journal Article
Closed access
TLTianhao Liu
Tianhao Liu
CYChao Yang
Chao Yang
Can ZhouCan Zhou
Can Zhou
YLYonggang Li
Yonggang Li
BSBei Sun
Bei Sun
The electrowinning process is a critical operation in nonferrous hydrometallurgy and consumes large quantities of power consumption. Current efficiency is an important process index related to power consumption, and it is vital to operate the electrolyte temperature close to the optimum point to ensure high current efficiency. However, the optimal control of electrolyte temperature faces the following challenges. First, the temporal causal relationship between process variables and current efficiency makes it difficult to estimate the current efficiency accurately and set the optimal electrolyte temperature. Second, the substantial fluctuation of influencing variables of electrolyte temperature leads to difficulty in maintaining the electrolyte temperature close to the optimum point. Third, due to the complex mechanism, building a dynamic electrowinning process model is intractable. Hence, it is a problem of index optimal control in the multivariable fluctuation scenario without process modeling. To get around this issue, an integrated optimal control method based on temporal causal network and reinforcement learning (RL) is proposed. First, the working conditions are divided and the temporal causal network is used to estimate current efficiency accurately to solve the optimal electrolyte temperature under multiple working conditions. Then, an RL controller is established under each working condition, and the optimal electrolyte temperature is placed into the controller’s reward function to assist in control strategy learning. An experiment case study of the zinc electrowinning process is provided to verify the effectiveness of the proposed method and to show that it can stabilize the electrolyte temperature within the optimal range without modeling.

1 December 2021 in Industrial & Engineering Chemistry Research
Verified
Journal Article
Closed access
CZCan Zhou
Can Zhou
TLTianhao Liu
Tianhao Liu
HZHongqiu Zhu
Hongqiu Zhu
YLYonggang Li
Yonggang Li
FLFanbiao Li
Fanbiao Li

4 January 2024 in Measurement Science and Technology
Verified
Journal Article
Open access
PDF file
Can ZhouCan Zhou
Can Zhou
CZCanzong Zhou
Canzong Zhou
HZHongqiu Zhu
Hongqiu Zhu
TLTianhao Liu
Tianhao Liu
Barrel distortions often exist in images captured by wide-angle lenses, and the presence of barrel distortions reduces the label-making accuracy of algorithms and the precision rate of final target detection and semantic recognition. To reduce the interference of barrel distortions on imaging, we have proposed a lightweight image rectification network automatic image rectification CNN (AIR-CNN) for barrel distortion. The network is based on a parameter sharing (PS) convolutional neural network structure, which is trained on the distorted image dataset to predict the pixel displacement field between the distorted image and the rectified image, and finally restores the rectified image based on the predicted pixel displacement field. The experimental results show that the AIR-CNN can greatly reduce the number of network parameters through the PS mechanism and implicitly learns the texture features by asymmetric convolution kernels to obtain higher rectification accuracy at a lower computational cost, and automatically obtain the distortion parameters of the camera without special calibration methods. The AIR-CNN outperforms previous image rectification methods in both intuitive and quantitative comparisons (EPE, PSNR, NRMSE, SSIM).

26 January 2022 in IEEE Transactions on Instrumentation and Measurement
Verified
Journal Article
Closed access
Can ZhouCan Zhou
Can Zhou
TLTianhao Liu
Tianhao Liu
HZHongqiu Zhu
Hongqiu Zhu
FLFanbiao Li
Fanbiao Li
KHKeke Huang
Keke Huang
YTYancho Todorov
Yancho Todorov
Turbidity has been used as a significant indicator of water quality, so turbidity measurement is widely applied in sewage treatment and other fields. In the traditional measurement method of turbidity, a dark, closed measuring environment is required to reduce the interference of ambient light, which limits the application of turbidity measurement. To improve the adaptability of turbidity measurement to different light scenes, a multiple light scenes suited turbidity analysis method based on image recognition and information fusion is proposed. First, a turbidity image acquisition system is designed. After image preprocessing, prediction network groups for multiple light scenes are established, and two optimal prediction networks are adaptively selected according to different ambient light scenes, improving adaptability to multiple measuring environments. Second, to improve prediction accuracy, Dempster–Shafer (D–S) evidence theory is adopted to realize the information fusion of network prediction results. Three different light scenes of 0, 50, and 100 lx are built through experiments, and the results show that the accuracy of the proposed method in the three light scenes is above 95%, which demonstrates the adaptability to multiple light scenes and provides a new way of industrial online measurement.

30 April 2025 in IEEE Transactions on Systems, Man, and Cybernetics: Systems
Verified
Journal Article
Closed access
TLTianhao Liu
Tianhao Liu
CYChao Yang
Chao Yang
Can ZhouCan Zhou
Can Zhou
YLYonggang Li
Yonggang Li
BSBei Sun
Bei Sun
The process industry is a key manufacturing process that consumes a vast amount of energy consumption. On the premise of ensuring process stability, controlling process variables to operate the process close to the optimal working condition plays a critical role in reducing energy consumption. Reinforcement learning (RL), using trial and error to learn control strategies, has received much attention. However, the substantial fluctuations of process variables and the switching delay gap of the process industry result in a high-dimension state-action space, making it difficult to learn control strategies efficiently, and there is no guarantee of control stability. To get around these issues, first, a generic knowledge-extracted method for process industry RL control is proposed. It does not require laborious expert knowledge acquisition processes. Second, to improve learning efficiency, the implicit knowledge is extracted using decision trees from operation trajectory data and embedded into agent controllers. Third, an explicit knowledge-oriented reward constructing method is designed to guarantee control stability. A case of the zinc electrowinning process is provided to validate its superiority. The result shows that it can reduce power consumption while stabilizing process variables within the spec limits, without a laborious expert knowledge acquisition process.

11 March 2024 in Measurement
Verified
Journal Article
Closed access
CZCan Zhou
Can Zhou
JWJiali Wu
Jiali Wu
TLTianhao Liu
Tianhao Liu
HZHongqiu Zhu
Hongqiu Zhu
HLHongmin Liu
Hongmin Liu
BSBei Sun
Bei Sun