A Dynamic Head Gesture Recognition Method for Real-time Intention Inference and Its Application to Visual Human-robot Interaction

Jialong Xie,Botao Zhang,Qiang Lu,Oleg Borisov 제어·로봇·시스템학회 2024 International Journal of Control, Automation, and Vol.22 No.1

Head gesture is a natural and non-verbal communication method for human-computer and human-robot interaction, conveying attitudes and intentions. However, the existing vision-based recognition methods cannot meet the precision and robustness of interaction requirements. Due to the limited computational resources, applying most high-accuracy methods to mobile and onboard devices is challenging. Moreover, the wearable device-based approach is inconvenient and expensive. To deal with these problems, an end-to-end two-stream fusion network named TSIR3D is proposed to identify head gestures from videos for analyzing human attitudes and intentions. Inspired by Inception and ResNet architecture, the width and depth of the network are increased to capture motion features sufficiently. Meanwhile, convolutional kernels are expanded from the spatial domain to the spatiotemporal domain for temporal feature extraction. The fusion position of the two-stream channel is explored under an accuracy/complexity trade-off to a certain extent. Furthermore, a dynamic head gesture dataset named DHG and a behavior tree are designed for human-robot interaction. Experimental results show that the proposed method has advantages in real-time performance on the remote server or the onboard computer. Furthermore, its accuracy on the DHG can surpass most state-of-the-art vision-based methods and is even better than most previous approaches based on head-mounted sensors. Finally, TSIR3D is applied on Pepper Robot equipped with Jetson TX2.

Design, Synthesis and Evaluation of Pentacyclic Triterpenoids Similar to Glycyrrhetinic Acid Via Combination of Chemical and Microbial Modification as Glycogen Phosphorylases Inhibitor

( Yuyao Zhu ),( Jian Zhang ),( Xiaode Huang ),( Bin Chen ),( Hua Qian ),( Botao Zhao ) 한국미생물생명공학회(구 한국산업미생물학회) 2018 Journal of microbiology and biotechnology Vol.28 No.11

A series of pentacyclic triterpenoids similar to glycyrrhetinic acid were designed and synthesized via the combination of chemical modification and microbial catalysis. All products were screened for the glycogen phosphorylases inhibitory activities in vitro. Within this series of derivatives, compound 5 displayed good inhibitory activities with IC₅₀ value of 27.7 μM, which is better than that of the other derivatives and glycyrrhetinic acid. Structure- activity relationship (SAR) analysis of these inhibitors was also discussed.

Manipulation Planning with Soft Constraints by Randomized Exploration of the Composite Configuration Space

Jiangping Wang,Shirong Liu,Botao Zhang,Changbin Yu 제어·로봇·시스템학회 2021 International Journal of Control, Automation, and Vol.19 No.3

In this paper, an efficient and probabilistic complete planning algorithm called Composite-space RRT is presented to address motion planning with soft constraints for spherical wrist manipulators. Firstly, we propose a novel configuration space termed Composite Configuration Space (“Composite Space” for short), which is composed of the joint space and the task space. Then, collision-free paths are generated in the composite space by the Rapidly-exploring Random Trees (RRT) algorithm. Finally, the planned paths in the composite space are mapped into the corresponding joint-space paths by a local planner. As the analytical inverse kinematics (IK) of the spherical wrist is used in the local planner, the proposed Composite-space RRT algorithm is characterized by high efficiency and no numerical iteration. Moreover, this approach can effectively improve the smoothness of the end-effector orientation path. The effectiveness of the proposed algorithm is demonstrated on the Willow Garage’s PR2 simulation platform with two typical orientation-constrained cases.

Active Disturbance Rejection Control-based Robust Model Predictive Current Control for Induction Motor

He Hucheng,Liu Botao,Wang Qin,Tan Fuchen,Gui Haoya,Zhang Chenyang 대한전기학회 2022 Journal of Electrical Engineering & Technology Vol.17 No.6

Induction motor (IM) is widely used in numerous industrial applications. However, achieving high-performance control of IM by using conventional control algorithms is diffi cult because of the mathematical model of high-order, strong coupling, and nonlinearity. Although fi nite control set model predictive current control (FCS-MPCC) has attracted considerable attention because of its simple structure, fast dynamic response, and excellent performance, its performance is degraded substantially if a mismatch exists between model parameters and actual machine parameters. To overcome these problems, active disturbance rejection controller based MPCC (ADRC-MPCC) was proposed for improving the dynamic property and robustness of IM in this paper. The model errors on the IM caused by the load torque and parameter changes were observed and compensated using the extended state observer and nonlinear state error feedback. Two outer loops, namely the ADRC speed loop controller and ADRC fl ux loop controller were designed to improve the rejection disturbance performance of IM speed control system. Furthermore, the calculation process of MPCC of the inner loop is also simplifi ed by ADRC-MPCC. The proposed control strategy was compared and verifi ed with PI control and FCS-MPCC by using MATLAB/Simulink. Simulation and experimental results confi rmed the robustness and dynamic performance of the proposed control strategy

Preparation of Co₃O₄/NF Anode for Lithium-ion Batteries

Tian, Shiyi,Li, Botao,Zhang, Bochao,Wang, Yang,Yang, Xu,Ye, Han,Xia, Zhijie,Zheng, Guoxu The Korean Electrochemical Society 2020 Journal of electrochemical science and technology Vol.11 No.4

Due to its characteristics of light weight, high energy density, good safety, long service life, no memory effect, and environmental friendliness, lithium-ion batteries (LIBs) are widely used in various portable electronic products. The capacity and performance of LIBs largely depend on the performance of electrode materials. Therefore, the development of better positive and negative materials is the focus of current research. The application of metal organic framework materials (MOFs) derivatives in energy storage has attracted much attention and research. Using MOFs as precursors, porous metal oxides and porous carbon materials with controllable structure can be obtained. In this paper, rod-shaped Co-MOF-74 was grown on Ni Foam (NF) by hydrothermal method, and then Co-MOF-74/NF precursor was heat-treated to obtain rodshaped Co₃O₄/NF. Ni Foam was skeleton structured, which effectively relieved. The change of internal stress changes and destroys the structural volume of the electrode material and reduces the capacity attenuation. Co₃O₄/NF composite material has a specific discharge capacity of up to 1858 mA h/g for the first time, and a reversible capacity of up to 902.4 mA h/g at a current density of 200 mA/g, and has excellent rate and impedance performance. The synthesis strategy reported in this article opens the way to design high-performance electrodes for energy storage and electrochemical catalysis.

Effects of Impeller Geometry on the 11α-Hydroxylation of Canrenone in Rushton Turbine-Stirred Tanks

( Shaofeng Rong ),( Xiaoqing Tang ),( Shimin Guan ),( Botao Zhang ),( Qianqian Li ),( Baoguo Cai ),( Juan Huang ) 한국미생물생명공학회(구 한국산업미생물학회) 2021 Journal of microbiology and biotechnology Vol.31 No.6

The 11α-hydroxylation of canrenone can be catalyzed by Aspergillus ochraceus in bioreactors, where the geometry of the impeller greatly influences the biotransformation. In this study, the effects of the blade number and impeller diameter of a Rushton turbine on the 11α-hydroxylation of canrenone were considered. The results of fermentation experiments using a 50 mm four-blade impeller showed that 3.40% and 11.43% increases in the conversion ratio were achieved by increasing the blade number and impeller diameter, respectively. However, with an impeller diameter of 60 mm, the conversion ratio with a six-blade impeller was 14.42% lower than that with a four-blade impeller. Data from cold model experiments with a large-diameter six-blade impeller indicated that the serious leakage of inclusions and a 22.08% enzyme activity retention led to a low conversion ratio. Numerical simulations suggested that there was good gas distribution and high fluid flow velocity when the fluid was stirred by large-diameter impellers, resulting in a high dissolved oxygen content and good bulk circulation, which positively affected hyphal growth and metabolism. However, a large-diameter six-blade impeller created overly high shear compared to a large-diameter four-blade impeller, thereby decreasing the conversion ratio. The average shear rates of the former and latter cases were 43.25 s^-1 and 35.31 s^-1, respectively. We therefore concluded that appropriate shear should be applied in the 11α-hydroxylation of canrenone. Overall, this study provides basic data for the scaled-up production of 11α-hydroxycanrenone.

A Dominant Mutation in ARL2 Causes Impaired Adventitious Root Development in Rice

Shiping Liu,Yanhong Xue,Xiaofei Wang,Botao Zhang,Yuting Bi,Min Qiu,Guangxi Wang,Ping Wu 한국식물학회 2011 Journal of Plant Biology Vol.54 No.4

Adventitious roots are vital for water and nutrient assimilation by cereal crops because they comprise the bulk of the fibrous root system. We isolated and analyzed a rice mutant, adventitious rootless 2 (arl2), which failed to initiate adventitious root primordia during early development. Its seminal root produced fewer lateral roots than from the wild type. This mutant also exhibited pleiotropic phenotypes of longer and thicker seminal roots, a different morphology for the first leaf, delayed heading, and a greater tiller angle. Physiological experiments showed that exogenous auxin and ethylene could rescue adventitious root growth, a response opposite that for two previously reported mutants, arl1 and gnom1. Activity in the auxin signal pathway and the polar auxin transport system was normal for arl2. Compared with the wild type, arl2 plants showed enhanced sensitivity to ethephon but decreased sensitivity to AgNO_3, an inhibitor of ethylene. Genetics analysis demonstrated that this mutant is controlled by a single dominant gene; ARL2 was mapped within a 100-kb interval on the short arm of chromosome 2.

Experimental Investigation on Aerodynamic Interference of Vehicles on Single-Level Rail-Cum-Road Bridge under Crosswinds

Jiajun He,Jin Zhu,Huoyue Xiang,Botao Zhang,Yongle Li,Bing Han 대한토목학회 2023 KSCE Journal of Civil Engineering Vol.27 No.8

Single-level rail-cum-road steel box girder is a relatively new form of bridge superstructure that accommodates railway and highway in the same level. The wind flow pattern over the bridge deck is quite complex and a new issue of aerodynamic interference between vehicles also rise up. This paper conducted an in-depth investigation on the aerodynamic characteristics of vehicles on a single-level rail-cum-road bridge as well as the aerodynamic interference among vehicles. The results reveal that the bridge deck makes the aerodynamic coefficients of vehicles on windward lanes vary a lot with respect to vehicle location and vehicle type, while it also well protects the train and leeward road vehicles from large wind load. Among all the vehicles, the van gets several of the largest aerodynamic coefficients and is considered as a critical vehicle. In terms of the vehicles’ interference, the upstream truck trailer brings significant aerodynamic variation for the overtaking vehicle, but its inadequate shelter effect yields fluctuation in the variation. An upstream truck trailer brings significant rise for the aerodynamic load of the train, larger distance between the train and the truck trailer will bring larger increase on the train’s aerodynamic load.

Performance study on the whole vibration process of a museum induced by metro

Weiguo Yang,Meng Wang,Jianquan Shi,Jiaqi Ge,Nan Zhang,Botao Ma 국제구조공학회 2015 Structural Engineering and Mechanics, An Int'l Jou Vol.55 No.2

The vibrations caused by metro operation propagate through surrounding soil, further induce secondary vibrations of the nearby underground structures and adjacent buildings. In order to investigate the effects of vibrations caused by metro on use performance of buildings, vibration experiment of Chengdu museum was carried out firstly. Then, the coupling tunnel-soil-structure finite element model was established with software ANSYS detailedly, providing a useful tool for investigating the vibration performances of structures. Furthermore, the dynamic responses and vibration predictions of museum building were obtained respectively by the whole process time-domain analysis and frequency-domain analysis, which were compared with the vibration reference values of museum. Quantitative analyses of the museum building performance were carried out, and the possible tendency and changing laws of vibration level with floors were proposed. Finally, the related vibration isolation measures were compared and discussed. The tests and analysis results show that: The vertical vibration responses almost increased with the increasing of building floors, while weak floors existed for the curve of horizontal vibration; The vertical vibrations were larger than the horizontal vibrations, indicating the vibration performances of building caused by metro were characterized with vertical vibrations; The frequencies of the museum corresponding to the peak vibration levels were around 6~17Hz; The damping effect of structure with 33m-span cantilever on vertical vibration was obvious, however, the damping effect of structure with foundation vibration isolators was not obvious.

Rapid removal of low concentrations of mercury from wastewater using coal gasification slag

Liangyan Duan,Xiude Hu,Deshuai Sun,Yongzhuo Liu,Qing-Jie Guo,Tongkai Zhang,Botao Zhang 한국화학공학회 2020 Korean Journal of Chemical Engineering Vol.37 No.7

Coal gasification slag (CGS) is a carbon-containing solid waste used as an adsorbent to remove low concentrations of mercury from wastewater in a series of batch tests to assess its adsorption properties and safe storage. The results showed that the adsorption of mercury on CGS was a very rapid and efficient process, and adsorption equilibrium was reached in only 10-40 min. A pseudo-second-order kinetics model provided a better fit to the equilibrium data. The adsorption capacity on CGS was just slightly below the value of active carbon. CGS showed the highest mercury removal efficiency at a solution pH of 4. Although the presence of other metal cations and anions affected the adsorption, CGS showed good selectivity for mercury ions. The adsorption of mercury was not affected by low concentrations of Cr3+ or Cu2+. The negative interference of anions on the removal efficiency followed the order: Cl>H2PO4 > CO3 2. The adsorption mechanism related to the functional groups included ion exchange, precipitation, coordination complexation, and surface complexation. Mercury adsorbed on CGS leached very slowly in weakly acidic or basic solution. All results of the study indicate that CGS is an economical and safe adsorbent for potential industrial applications.