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An Approach for Adaptive limbless Locomotion Using a CPG-Based Reflex Mechanism

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Journal of Bionic Engineering 2014年第3期11卷 389-399页

作者： Guoyuan Li Houxiang Zhang Jianwei Zhang Hans Petter Hildre Faculty of Maritime Technology and Operations Aalesund University College Aalesund 6009 Norway Department of Computer Science University of Hamburg Hamburg 22527 Germany

Animals＇ free movement in natural environments has attracted many researchers to explore control methods for bio-inspired robots. This paper presents a novel reflex mechanism based on a Central Pattern Generator （CPG） for adaptive locomotion of limbless robots. First, inspired by the concept of reflex arc, the reflex mechanism is designed on a connectionist CPG model. Since the CPG model inspired by the spinal cord of lampreys is developed at the neuron level, it provides a possible natural solution for sensory reflex integration. Therefore, sensory neurons that bridge the external stimuli and the CPG model, together with the concept of reflex arc, are utilized for designing the sensory reflex mechanism. Then, a border reflex and a body reflex are further developed and applied on the ends and the middle part of a limbless robot, respectively. Finally, a ball hitting scenario and a corridor passing scenario are designed to verify the proposed method. Results of simulations and on-site experiments show the feasibility and effectiveness of the reflex mechanism in realizing fast response and adaptive limbless locomotion.

关键词： sensory reflex mechanism reflex arc central pattern generator limbless locomotion

Cloud Detection and Centroid Extraction of Laser Footprint Image of GF-7 Satellite Laser Altimetry

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Journal of Geodesy and Geoinformation Science 2021年第3期4卷 1-12页

作者： Jiaqi YAO Guoyuan Li Jiyi CHEN Genghua HUANG Xiongdan YANG Shuaitai ZHANG College of Geomatics Shandong University of Science and TechnologyQingdao 266590China Land Satellite Remote Sens-ing Application Center Ministry of Natural Resources of P.R.ChinaBeijing100048China Key Laboratory of Space Active Opto-electronics Technology Chinese Academy of SciencesShanghai200083China College of Mapping and Geomatics Lanzhou Jiaotong UniversityLanzhou 730070China

The laser altimeter loaded on the GaoFen-7(GF-7)satellite is designed to record the full waveform data and footprint image,which can obtain high-precision elevation control points for stereo image.The footprint camera equipped on the GF-7 laser altimetry system can capture the energy distribution at the time of laser emission and the image of the ground object where the laser falls,which can be used to judge whether the laser is affected by the cloud.At the same time,the centroid of laser spot on the footprint image can be extracted to monitor the change of laser pointing stability.In this manuscript,a data quality analysis scheme of laser altimetry based on footprint image is presented.Firstly,the cloud detection of footprint image is realized based on deep learning.The fusion result of the model is about 5%better than that of the traditional cloud detection algorithm,which can quickly and accurately determine whether the laser spot is affected by cloud.Secondly,according to the characteristics of footprint image,a threshold constrained ellipse fitting method for extracting the centroid of laser spot is proposed to monitor the pointing stability of long-period lasers.Based on the above method,the change of laser spot centroid since GF-7 satellite was put into operation is analyzed,and the conclusions obtained have certain reference significance for the quality control of satellite laser altimetry data and the analysis of pointing angle stability.

关键词： GF-7 quality control satellite laser altimetry laser footprint image cloud detection stability analysis of laser pointing angle

Bionic Flapping Pectoral Fin with Controllable Spatial Deformation

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Journal of Bionic Engineering 2019年第5期16卷 916-930页

作者： Yueri Cai lingkun Chen Shusheng Bi Guoyuan Li Houxiang Zhang Robotics Institute Beihang UniversityBeijing 100191China Department of Ocean Operations and Civil Engineering Norwegian University of Science and TechnologyAalesund 6025Norway

This paper presents the design of a bionic pectoral fin with fin rays driven by multi-joint mechanism.Inspired by the cownose ray,the bionic pectoral fin is modeled and simplified based on the key structure and movement parameters of the cownose ray's pectoral fin.A novel bionic propulsion fin ray composed of a synchronous belt mechanism and a slider-rocker mechanism is designed and optimized in order to minimize the movement errors between the designed fin rays and the spanwise curves observed from the cownose ray,and thereby reproducing an actively controllable flapping deformation.A bionic flapping pectoral fin prototype is developed accordingly.Observations verify that the bionic pectoral fin flaps consistently with the design rule extracted from the cownose ray.Experiments in a towing tank are set up to test its capability of generating the lift force and the propulsion force.The movement parameters within the usual propulsion capabilities of the bionic pectoral fm are utilized:The flapping frequency of 0.2 Hz-0.6 Hz,the flapping amplitude of 3°-18°,and the phase di^rence of 10°-60°.The results show that the bionic pectoral fin with actively controllable spatial deformation has expected propulsion performance,which supports that the natural features of the cownose ray play an important role in designing and developing a bionic prototype.

关键词： cownose ray bionic pectoral fin controllable deformation multiple fin rays propulsion perfonnance

Superoxide-like Cu/GO single-atom catalysts nanozyme with high specificity and activity for removing superoxide free radicals

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Nano Research 2022年第10期15卷 8804-8809页

作者： Mingju Lu Jialu Wang guoyuan Ren Fengjuan Qin Zhiqiang Zhao Kai li Wenxing Chen Yuqing lin Department of Chemistry Capital Normal UniversityBeijing 100048China Energy&Catalysis Center School of Materials Science and EngineeringBeijing Institute of TechnologyBeijing 100081China

Although nanozyme has become an emerging area of research attracting extensive attention recently,the activity and specificity of currently reported nanozymes are generally lower than those of natural enzymes.Developing highly active and specific nanozymes is therefore extremely necessary and also remains a great challenge.Superoxide dismutase(SOD)catalyzes the disproportionation of cytotoxic O_(2)·^(−)into hydrogen peroxide and oxygen,and plays an important role in reducing human oxidative stress.In this work,we prepare Cu single-atom catalysts(Cu/GO SACs,GO=graphene oxide)through a simple and low-cost strategy at room temperature using Cu foam and graphene oxide.Cu/GO SACs can maintain excellent catalytic activity under harsh environment.Compared with the natural enzyme,SOD-like Cu/GO SAC nanozyme has higher catalytic activity and meanwhile,it does not possess the common properties of other mimic enzymes often existing in nanomaterials.Based on the excellent SOD-like enzyme activity of Cu/GO SACs,it successfully eliminates the active oxygen in cigarette smoke.This work not only provides a new idea for the design and synthesis of nanozymes with excellent SOD mimetic properties,but also is promising in the treatment of lung injury and inflammatory diseases related to free radical production.

关键词： Cu/graphene oxide(GO)single-atom catalysts(SACs) superoxide dismutase(SOD)-like activity activity specificity superoxide free radicals

An Improved Protocol for Regioselective Ring-Opening of Sulfonyl Aziridines with Iodine Promoted by PPh3

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Chinese Journal of Chemistry 2013年第12期31卷 1508-1512页

作者： Jinfeng Zhang lingguo Meng Chuntao li guoyuan Xiao Department of Chemistry Huaibei Normal University Huaibei Anhui 235000 China

A new route to synthesize β-iodo amines from sulfonyl aziridines and iodine was developed in the presence of PPh3. This ring-opening reaction was an efficient and simple process to give fl-iodo amines in excellent yi... 详细信息

关键词： sulfonyl aziridines iodine ring-opening β-iodo amines PPh3

Safety Analysis of the Eco-Approach and Departure Application at a Signalized Corridor

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Tsinghua Science and Technology 2018年第2期23卷 157-171页

作者： Weixia li guoyuan Wu Yi Zhang Matthew J. Barth Department of Automation Tsinghua University Beijing 100084 China. Bourns College of Engineering-Center for Environmental Research and Technology (CE-CERT) University of California Riverside CA 92507 USA.

Various intelligent transportation systems and strategies for reducing vehicle fuel consumption and emissions have been developed. Energy and emissions could be reduced with the compromise of travel time in some environment-focused Connected Vehicle(CV) applications, which highlighted performance measures in terms of mobility and sustainability. Nevertheless, few studies have focused on safety assessment of such CV applications. In this study, a CV-based eco-driving application, namely, Eco-Approach and Departure(EAD), is selected as an example. A microscopic safety analysis tool, Surrogate Safety Assessment Model(SSAM), is utilized to assess the safety influence of EAD application in multiple scenarios. Further analysis is performed from two perspectives:(1) application users, i.e., EAD-equipped vehicles versus unequipped vehicles; and(2) traffic operators, i.e., overall traffic performance with and without the introduction of EAD. For each perspective, conflict statistics(e.g., frequency, time-to-collision distribution), overall and by type, are analyzed. Results indicate EAD is beneficial in improving the safety performance of equipped vehicles. The influence of EAD on overall traffic is scenario dependent, and a high penetration rate shows positive effects on network-wide safety benefits for most scenarios.

关键词： Eco-Approach and Departure(EAD) Surrogate Safety Assessment Model(SSAM) safety analysis conflict type Time-To-Collision(TTC)

高分七号卫星激光测高数据大型湖泊水位测量精度评估

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遥感学报 2022年第1期26卷 138-147页

作者：李国元唐新明自然资源部国土卫星遥感应用中心北京100048 江苏省地理信息资源开发与利用协同创新中心南京210023

卫星激光测高数据在湖泊水位测量方面具有重要的应用价值和独特优势,本文针对国产高分七号卫星上装备的线性体制全波形激光测高仪,开展在大型湖泊水位测量方面的应用探讨。介绍了高分七号卫星的基本参数,并与其他类卫星做了对比,分析了... 详细信息

卫星激光测高数据在湖泊水位测量方面具有重要的应用价值和独特优势,本文针对国产高分七号卫星上装备的线性体制全波形激光测高仪,开展在大型湖泊水位测量方面的应用探讨。介绍了高分七号卫星的基本参数,并与其他类卫星做了对比,分析了影响湖泊水位测量精度的卫星侧摆、大气散射、回波波形饱和等因素,研究了湖泊水面激光点的提取方法,结合ICESat、ICESat-2在青海湖和哈拉湖上的激光点开展了对比分析,并利用RTK-GPS测量方式对呼伦湖冰面激光点进行了实地精度验证。结果表明,高分七号卫星湖面激光点虽然稀疏,但内部一致性较好,其中青海湖面高分七号两波束激光高程标准偏差分别为0.056 m和0.080 m,与ICESat的0.079 m相当;相邻时间在哈拉湖同一湖面的高分七号两个波束与ICESat-2的高程均值相差分别为-5.2 cm和-8.0 cm;经实地测量评价两波束的湖面激光点绝对高程精度分别为:-0.030±0.109 m和-0.195±0.049 m。高分七号激光测高仪测量湖泊水位从精度上是可行的,但还存在激光重频率偏低、观测能力弱等问题。相关结论对于拓展高分七号卫星激光测高数据在大型湖泊水位测量的应用以及后续激光测高卫星的立项论证均具有参考价值。

关键词：高分七号卫星激光测高 ICESat-2 湖泊水位精度评估

Additively manufactured biodegradable porous magnesium implants for elimination of implant-related infections:An in vitro and in vivo study

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Bioactive Materials 2022年第2期7卷 140-152页

作者： Kai Xie Nanqing Wang Yu Guo Shuang Zhao Jia Tan Lei Wang Guoyuan Li Junxiang Wu Yangzi Yang Wenyu Xu Juan Chen Wenbo Jiang Penghuai Fu Yongqiang Hao Shanghai Key Laboratory of Orthopaedic Implants Department of Orthopaedic SurgeryShanghai Ninth People’s HospitalShanghai Jiao Tong University School of MedicineShanghai200011China National Engineering Research Center of light Alloy Net Forming&State Key Laboratory of Metal Matrix Composite Shanghai Jiao Tong UniversityShanghai200240China Musculoskeletal Tumor Center Peking University People’s Hospital100044BeijingChina Department of Orthopedics The First Affiliated Hospital of USTCDivision of Life Sciences and MedicineUniversity of Science and Technology of ChinaHefeiAnhui230001China Clinical and Translational Research Center for 3D Printing Technology Shanghai Ninth People’s HospitalShanghai Jiao Tong University School of MedicineShanghai200011China

Magnesium(Mg)alloys that have both antibacterial and osteogenic properties are suitable candidates for orthopedic implants.However,the fabrication of ideal Mg implants suitable for bone repair remains challenging because it requires implants with interconnected pore structures and personalized geometric shapes.In this study,we fabricated a porous 3D-printed Mg-Nd-Zn-Zr(denoted as JDBM)implant with suitable mechanical properties using selective laser melting technology.The 3D-printed JDBM implant exhibited cytocompatibility in MC3T3-E1 and RAW267.4 cells and excellent osteoinductivity in vitro.Furthermore,the implant demonstrated excellent antibacterial ratios of 90.0% and 92.1% for methicillin-resistant S.aureus(MRSA)and Escherichia coli,respectively.The 3D-printed JDBM implant prevented MRSA-induced implant-related infection in a rabbit model and showed good in vivo biocompatibility based on the results of histological evaluation,blood tests,and Mg2+deposition detection.In addition,enhanced inflammatory response and TNF-α secretion were observed at the bone-implant interface of the 3D-printed JDBM implants during the early implantation stage.The high Mg^(2+)environment produced by the degradation of 3D-printed JDBM implants could promote M1 phenotype of macrophages(Tnf,iNOS,Ccl3,Ccl4,Ccl5,Cxcl10,and Cxcl2),and enhance the phagocytic ability of macrophages.The enhanced immunoregulatory effect generated by relatively fast Mg^(2+)release and implant degradation during the early implantation stage is a potential antibacterial mechanism of Mg-based implant.Our findings indicate that 3D-printed porous JDBM implants,having both antibacterial property and osteoinductivity,hold potential for future orthopedic applications.

关键词： Magnesium implants 3D printing Implant-related infections Antibacterial activity

Bicontinuous porous membranes with micro-nano composite structure using a facile atomization-assisted nonsolvent induced phase separation method

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Frontiers of Chemical Science and Engineering 2022年第8期16卷 1268-1280页

作者： Jing Wang guoyuan Pan Yu li Yang Zhang Hongwei Shi Xuanbo liu Hao Yu Muhua Zhao Yiqun liu Changjiang Wu College of Materials Science and Engineering Beijing University of Chemical TechnologyBeijing 100029China SINOPEC Beijing Research Institute of Chemical Industry Beijing 100013China

The micro-nano composite structure can endow separation membranes with special surface properties,but it often has the problems of inefficient preparation process and poor structural stability.In this work,a novel atomization-assisted nonsolvent induced phase separation method,which is also highly efficient and very simple,has been developed.By using this method,a bicontinuous porous microfiltration membrane with robust micro-nano composite structure was obtained via commercially available polymers of polyacrylonitrile and polyvinylpyrrolidone.The formation mechanism of the micro-nano composite structure was proposed.The microphase separation of polyacrylonitrile and polyvinylpyrrolidone components during the atomization pretreatment process and the hydrogen bonding between polyacrylonitrile and polyvinylpyrrolidone molecules should have resulted in the nano-protrusions on the membrane skeleton.The membrane exhibits superhydrophilicity in air and superoleophobicity underwater.The membrane can separate both surfactant-free and surfactant-stabilized oil-in-water emulsions with high separation efficiency and permeation flux.With excellent antifouling property and robust microstructure,the membrane can easily be recycled for long-term separation.Furthermore,the scale-up verification from laboratory preparation to continuous production has been achieved.The simple,efficient,cost-effective preparation method and excellent membrane properties indicate the great potential of the developed membranes in practical applications.

关键词： atomization nonsolvent induced phase