AGV Motion Balance and Motion Regulation Under Complex Conditions

Yanming Quan,Ma Lei,Weizhao Chen,Ronghui Wang 제어·로봇·시스템학회 2022 International Journal of Control, Automation, and Vol.20 No.2

AGV cargo robot is widely used in flexible production line of intelligent factory. Different conditions for cargo instability occurs in different production line scenarios, different loading conditions and different movement states, which greatly affect the security and reliability of AGV cargo transport. In order to realize the acceleration limits of the buckling critical instability state under different loading and motion states, a multi-sensor sensing system was built on the AGV platform. The inertial measurement unit, pressure sensor and odometer were used to realize the cargo state’s real-time perception and AGV motion state. The pressure sensor and inertial measurement unit were used to measure the cargo gravity center position that affects the carry stability and neural network algorithm training was used to get accurate judgment of different motion states. The kinematic mechanical equilibrium model was established to analyze the relative equilibrium state of AGV and cargo under different motion states and to determine the cargo critical instability acceleration constraint conditions under different transport conditions of different goods. The test results show that the platform can obtain the cargo gravity center position and perceive the AGV motion state in real-time, feedback the acceleration constraint under the current motion state in real-time and regulate the AGV to realize the safe and stable delivery of the cargo at any time under the multi-sensor perception.

Autogenous Shrinkage and Crack Resistance of Carbon Nanotubes Reinforced Cement‑Based Materials

Yanming Liu,Tao Shi,Yujing Zhao,Yuan Gu,Zhifang Zhao,Jiabin Chen,Bingmiao Zheng,Shichong Shi 한국콘크리트학회 2020 International Journal of Concrete Structures and M Vol.14 No.5

Cracking caused by shrinkage deformation of cement-based materials at early age is a major problem leading to material failure in restrained conditions. Carbon nanotubes (CNTs) are incorporated into cement-based materials, and the autogenous shrinkage and crack resistance of the new composite materials obtained by linear shrinkage and ring tests are studied to solve the destruction of the materials caused by the shrinkage of cement-based materials. The results showed that addition of CNTs significantly inhibited the autogenous shrinkage of cement-based materials with maximum reduction rate above 40%. CNTs also significantly improved the cracking resistance of cement-based materials. The optimal effect was noticed at CNTs content of 0.1 wt%. The incorporation of CNTs not only inhibits the autogenous shrinkage of cement-based materials, but also inhibits the drying shrinkage of cement-based materials to some extent. Therefore, carbon nanotubes have the potential to solve the destruction of materials caused by shrinkage of cement-based materials.

Cloning and Sequence Analysis of Wild Argali ISG15 cDNA

Sun, Yanming,Chen, Kaili,Shen, Wen,Cui, Rupeng,Lu, Haifu Asian Australasian Association of Animal Productio 2014 Animal Bioscience Vol.27 No.4

The complete coding sequence of Wild Argali ISG15 cDNA was generated by rapid amplification of cDNA ends. The ISG15 cDNA was 642 bp with an open reading frame of 474 bp, which encoded a 17.47 kDa protein composed of 157 amino acids. Its amino acid sequence shared 97.9%, 80.8%, 91.4%, 94.3%, 78.3% identity with those of ISG15cDNA from Ovis aries (accession no. NM001009735.1), Capra hircus (accession no. HQ329186.1), Bos taurus (accession no. BC102318.1), Bubalus bubalis (accession no. HM543269.1), and Sus scrofa (accession no. EU647216.1), respectively. The entire coding sequence was inserted into the pET-28a vector and expressed in E. coli. The recombinant protein corresponded to the expected molecular mass of 25 kDa as judged by SDS-PAGE, and it was detected in the bacterial inclusion bodies. The expressed protein could be purified by $Ni^{2+}$ chelate affinity chromatography and the results from the lymphocyte proliferation test showed that the product could stimulate lymphocyte proliferation very well (p<0.05), which further confirmed its biological activity.

Cerebellar Structural Abnormality in Autism Spectrum Disorder: A Magnetic Resonance Imaging Study

Lu Qifang,Chen Jin,Wang Yanming,Huang Li,Jiang Zhoufan,Nguchu Benedictor Alexander,Chen Shishuo,Qiu Bensheng,Wang Xiaoxiao 대한신경정신의학회 2023 PSYCHIATRY INVESTIGATION Vol.20 No.4

Objective This study uses structural magnetic resonance imaging to explore changes in the cerebellar lobules in patients with autism spectrum disorder (ASD) and further analyze the correlation between cerebellar structural changes and clinical symptoms of ASD.Methods A total of 75 patients with ASD and 97 typically developing (TD) subjects from Autism Brain Imaging Data Exchange dataset were recruited. We adopted an advanced automatic cerebellar lobule segmentation technique called CEREbellum Segmentation to segment each cerebellar hemisphere into 12 lobules. Normalized cortical thickness of each lobule was recorded, and group differences in the cortical measures were evaluated. Correlation analysis was also performed between the normalized cortical thickness and the score of Autism Diagnostic Interview-Revised.Results Results from analysis of variance showed that the normalized cortical thickness of the ASD group differed significantly from that of the TD group; specifically, the ASD group had lower normalized cortical thickness than the TD group. Post-hoc analysis revealed that the differences were more predominant in the left lobule VI, left lobule Crus I and left lobule X, and in the right lobule VI and right lobule Crus I. Lowered normalized cortical thickness in the left lobule Crus I in the ASD patients correlated positively with the abnormality of development evident at or before 36 months subscore.Conclusion These results suggest abnormal development of cerebellar lobule structures in ASD patients, and such abnormality might significantly influence the pathogenesis of ASD. These findings provide new insights into the neural mechanisms of ASD, which may be clinically relevant to ASD diagnosis.

Inter- and Intralayer Compression of Germanane

Ma, Yanmei,Chen, Yuanzheng,Ma, Yanming,Jiang, Shishi,Goldberger, Josh,Vogt, Thomas,Lee, Yongjae American Chemical Society 2014 JOURNAL OF PHYSICAL CHEMISTRY C - Vol.118 No.48

<P>The inter- and intralayer compression in germanane (GeH) were investigated at room temperature and pressures up to 10 GPa using a diamond-anvil cell (DAC) in combination with X-ray diffraction and micro-Raman spectroscopy. To examine the effect of the pressure-transmitting medium (PTM) on the interlayer compression leading to a possible insertion and exfoliation, two separate experiments were performed using water as PTM and no PTM. The results indicate that both the inter- and intralayer compression are dependent on the PMT, and the linear compressibility is 0.0274(1) and 0.0031(9) GPa<SUP>–1</SUP> along the <I>c</I>- and <I>a</I>-axis based on the shifts of the (002) and (100) reflections for water PTM, and 0.0190(6) and 0.0026(9) GPa<SUP>–1</SUP> along the <I>c</I>- and <I>a</I>-axis when pressurizing without PTM. High-pressure Raman spectra indicate that the intralayer Ge–Ge stretching mode is also dependent on the PMT. It exhibits a blue-shift of 3.01 and 2.66 cm<SUP>–1</SUP>/GPa when using water as PTM and without PTM, respectively. The equation of state determined from our experiments yields a bulk modulus of 9.6(2) GPa with <I>B</I>′<SUB>0</SUB> = 12 for GeH. Theoretical calculations were performed to understand the pressure dependence on the electronic band structure and the observed Raman spectrum.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/jpccck/2014/jpccck.2014.118.issue-48/jp507503j/production/images/medium/jp-2014-07503j_0008.gif'></P>

Cloning and sequence analysis of Wild Argali short palate, lung and nasal epithelium clone 1 cDNA

Wen Shen,Kaili Chen,Yanming Sun,Haiying Guo,Dongmei Chen,Yang Cao 아세아·태평양축산학회 2017 Animal Bioscience Vol.30 No.5

Objective: Experiments were conducted to clone the sequence of Wild Argali short palate, lung and nasal epithelium clone 1 (SPLUNC1) cDNA, and to lay the foundation for further study the biological function of Wild Argali SPLUNC1. Methods: The complete sequence of Wild Argali SPLUNC1 cDNA was generated by rapid amplification of cDNA ends. The entire coding sequence was inserted into the pPIC9K vector and expressed in Pichia pastoris (P. pastoris) GS115. The recombinant SPLUNC1 protein was detected by Western blot and purified by Ni2+ chelate affinity chromatography. The test of effect of the protein on Mycoplasma ovipneumoniae (MO) was performed with real-time polymerase chain reaction. Results: The Wild Argali SPLUNC1 cDNA was 1,076 bp with an open reading frame of 768 bp, which encoded a 26.49 kDa protein composed of 255 amino acids. Its amino acid sequence shared 98.4%, 96.9%, 94.5%, 90.2%, 80.8%, 78.4%, 78.3%, 72.5%, 72.3%, 68.8% identity with those of SPLUNC1 cDNA from Ovis aries (accession no. NP_001288334.1), Capra hircus (accession no. XP_005688516.1), Pantholops hodgsonii (accession no. XP_005979709.1), Bos taurus (accession no. NP_776851.1), Felis catus (accession no. XP_006929910.1), Homo sapiens (accession no. NP_001230122.1), Sus scrofa (accession no. NP_001005727.1), Chinchilla lanigera (accession no. NP_001269294.1), Mus musculus (accession no. NP_035256.2), and Rattus norvegicus (accession no. NP_742028.1), respectively. The recombinant protein corresponded to the expected molecular mass of 25.47 kDa as judged by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and it was detected in the supernatant of P. pastoris, and it could be purified. The results from the test of inhibition effect of argali recombinant SPLUNC1 protein on MO showed that the product could inhibit MO very well (p<0.01). Conclusion: The amino acid sequence of Wild Argali SPLUNC1 was different from other organisms. The recombinant SPLUNC1 protein has good biological activity.

Ghost Imaging with Different Speckle Sizes of Thermal Light

Jue Wang,Renlong Yu,Yu Xin,Yanming Shao,Yanru Chen,Qi Zhao 한국광학회 2016 Current Optics and Photonics Vol.20 No.1

In this paper, we theoretically and experimentally analyze the impact of speckle size of pseudo-thermallight source on ghost imaging. A larger size of speckle can bring improvements in SNR and visibility. At the same time, the edge blur of the retrieved image will become more serious. We also present a setupwhich can mitigate the edge blur of larger speckle while maintaining the advantages of higher SNR andvisibility by changing the speckle size of the object beam with a concave lens.

Adaptive active damping method of grid‑connected inverter based on model predictive control in weak grid

Ruinan Xue,Guojin Li,Hengzhou Tong,Yanming Chen 전력전자학회 2022 JOURNAL OF POWER ELECTRONICS Vol.22 No.7

The LCL-type grid-connected inverter based on finite control set model predictive control (FCS-MPC) is suitable for weak grids because of its good robustness and fast dynamic response. However, in an FCS-MPC-based system, the variable switching frequency causes the spread of the inverter-side current harmonic spectrum. Thus, the grid-side current may be distorted because the harmonics are amplified to the grid side due to the resonance peak of the LCL filter. To solve the above problem, this paper proposes an adaptive active damping (AD) method to eliminate the resonant effects. First, the system based on an MPC controller is regarded as a closed-loop system of the grid-side current, and the resonance peak is suppressed effectively by an AD, which consists of a virtual resistor and a virtual capacitor. Second, to balance the resonance suppression and dynamic performance of the system under weak grid conditions, the grid impedance is measured and the optimal AD values for different grid impedance are calculated online. Compared with the fixed-value AD, the proposed method has better resonance suppression and higher bandwidth. The effectiveness and feasibility of the proposed control strategy are verified by simulations and experiments.

Robust back‑stepping sliding mode control for LCL‑type grid‑connected inverters in weak grids

Xin Ding,Junyang Liang,Shangping Lu,Fannie Kong,Yanming Chen 전력전자학회 2023 JOURNAL OF POWER ELECTRONICS Vol.23 No.5

Gird impedance variations in a weak grid can easily lead to the instability of grid-connected inverters with an LCL filter. In this paper, a robust back-stepping sliding mode control strategy for the LCL-type grid-connected inverter is proposed to ensure local asymptotic stability. First, due to its nonlinear switching problem, the model is transformed into the Brunovsky canonical form of a linear system, using the exact feedback linearization theory. Then, to ensure global stability and rapid dynamic performance, a back-stepping sliding mode control strategy is recursively derived. Furthermore, under the premise of asymptotic stability, a robust scheme is developed to obtain appropriate parameters against grid impedance variations. Hence, the expected stability performance can be achieved and the dynamic performance can be improved in a weak grid. Finally, a 2 kW prototype is constructed, and experimental results demonstrate the effectiveness of the proposed controller when compared with the conventional back-stepping scheme.

Effect of Ion Source Current on the Microstructure and Properties of Cr-DLC Coatings Prepared by Ion Beam-Assisted Arc Ion Plating

Yao Cai,Huidong Liu,Ye Ma,Qiang Wan,Hao Cheng,Yan Liu,Yanming Chen,Qingsong Mei,Bing Yang 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2017 NANO Vol.12 No.5

Cr-containing diamond-like carbon (Cr-DLC) nanocomposite coatings were synthesized by ion beam-assisted arc ion plating with varying hollow cathode ion source (HCIS) currents. The morphologies, compositions and microstructures were characterized by scanning electronic microscopy (SEM), atomic force microscopy (AFM), X-Ray photoelectron spectrometer (XPS), Raman spectroscopy, grazing incidence X-ray diffraction (GIXRD) and high-resolution transmission electron microscopy (HRTEM). Hardness and friction coefficient were investigated by using nanoindentation and ball-on-disc tribometer, respectively. With no HCIS current, the coating exhibits the maximal growth rate and a rough surface, as well as lower hardness and elastic modulus. With the increasing HCIS current from 40 A to 80 A, the growth rate and the content of chromium carbide decrease obviously, the sp3/sp2 ratio increases initially to the maximum at the HCIS current of 60 A, the highest hardness and elastic modulus are obtained at the HCIS current of 50 A. It is also revealed that moderate HCIS current can reduce surface roughness obviously and promote tribological properties. The correlation of the HCIS current with the microstructure and performance of Cr-DLC coating has been established.