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Chaos synchronization of semiconductor lasers over 1040-km fiber relay transmission with hybrid amplification

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Photonics Research 2023年第6期11卷 953-960页

作者： LONGSHENG WANG JUNLI WANG YUSHAN WU YUEHUI SUN SONGSUI LI LIANSHAN YAN YUNCAI WANG ANBANG WANG key laboratory of Advanced Transducers and intelligent Control system Ministry of EducationTaiyuan 030024China College of Physics and Optoelectronics Taiyuan University of TechnologyTaiyuan 030024China School of Information Engineering Guangdong University of TechnologyGuangzhou 510006China guangdong Provincial key laboratory of Photonics Information Technology Guangzhou 510006China Center for Information Photonics&Communications School of Information Science and TechnologySouthwest Jiaotong UniversityChengdu 610031China

Optical chaos communication and key distribution have been extensively demonstrated with high-speed advantage but only within the metropolitan-area network range of which the transmission distance is restricted to around 300 *** secure-transmission requirement of the backbone fiber link,the critical threshold is to realize long-reach chaos ***,we propose and demonstrate a scheme of long-reach chaos synchronization using fiber relay transmission with hybrid amplification of an erbium-doped fiber amplifier(EDFA)and a distributed fiber Raman amplifier(DFRA).Experiments and simulations show that the hybrid amplification extends the chaos-fidelity transmission distance thanks to that the low-noise DFRA suppresses the amplified spontaneous emission noise and self-phase *** of the hybrid-relay conditions are studied,including launching power,gain ratio of DFRA to EDFA,single-span fiber length,and number of fiber span.A 1040-km chaos synchronization with a synchronization coefficient beyond 0.90 is experimentally achieved,which underlies the backbone network-oriented optical chaos communication and key distribution.

关键词： synchronization fiber amplifier

Robust tensor decomposition via orientation invariant tubal nuclear norms

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Science China(Technological Sciences) 2022年第6期65卷 1300-1317页

作者： WANG AnDong ZHAO QiBin JIN Zhong LI Chao ZHOU GuoXu School of Automation Guangdong University of TechnologyGuangzhou 510006China School of Computer Science and Engineering Nanjing University of Science and TechnologyNanjing 210094China Tensor Learning Team RIKEN Center for Advanced Intelligence ProjectTokyo 103-0027Japan key laboratory of intelligent Perception and system for High-Dimensional Information Ministry of EducationNanjing 210094China key laboratory of intelligent Detection and the Internet of Things in Manufacturing Ministry of EducationGuangzhou 510006China

Aiming at recovering an unknown tensor(i.e.,multi-way array)corrupted by both sparse outliers and dense noises,robust tensor decomposition(RTD)serves as a powerful pre-processing tool for subsequent tasks like classification and target detection in many computer vision and machine learning ***,tubal nuclear norm(TNN)based optimization is proposed with superior performance as compared with other tensorial nuclear norms for tensor ***,one major limitation is its orientation sensitivity due to low-rankness strictly defined along tubal orientation and it cannot simultaneously model spectral low-rankness in multiple *** this end,we introduce two new tensor norms called OITNN-O and OITNN-L to exploit multi-orientational spectral low-rankness for an arbitrary K-way(K≥3)*** further formulate two RTD models via the proposed norms and develop two algorithms as the ***,we establish non-asymptotic error bounds which can predict the scaling behavior of the estimation *** on real-world datasets demonstrate the superiority and effectiveness of the proposed norms.

关键词： tensor recovery t-SVD estimation error tensor completion

DEM analysis of passive arching in a shallow trapdoor under eccentric loading

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颗粒学报:英文版 2023年第6期77卷 14-28页

作者： Ruixiao Zhang Dong Su Xingtao Lin Guoping Lei Xiangsheng Chen key laboratory for Resilient Infrastructures of Coastal Cities(MOE) Shenzhen UniversityShenzhen518060China College of Civil and transportation Engineering Shenzhen UniversityShenzhen518060China Shenzhen key laboratory of Green Efficient and Intelligent Construction of Underground Metro StationShenzhen UniversityShenzhen518060China School of transportation Civil Engineering&ArchitectureFoshan UniversityFoshan528225China

This study analyzed the passive arching effect under eccentric loading by developing a series of trapdoor discrete numerical *** numerical models were validated by comparison with laboratory test *** deformation pattern,soil arching ratio,force chain distribution,and coordination number under various surcharge magnitudes and deviation distances were *** numerical results showed that the deformation diagram of soil particles can be divided into three zones:principal displacement zone,transition zone,and static *** an increase in the surcharge magnitude,the range of the principal displacement zone decreased,but the range of the transition region *** curve of the soil arching ratio on the trapdoor can be divided into three phases,which can be well characterized by the tangent *** passive arching effect is degraded by a *** ulti-mate soil arching ratio could be approximated as a W-shaped distribution along the+*** an increase in the trapdoor displacement,the force chain on the trapdoor gradually expanded outward to form an inverted funnel *** most powerful force on the trapdoor was mainly distributed on its *** average coordination number decreased gradually as the trapdoor moved upward.

关键词： Passive arching Eccentric load Discrete element method Forcechaindistribution Trapdoorapparatus

General Kinetostatic Modeling and Deformation Analysis of a Two-Module Rod-Driven Continuum Robot with Friction Considered

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Chinese Journal of Mechanical Engineering 2023年第3期36卷 110-122页

作者： Peiyi Wang Xinhua Yang Xiangyang Wang Sheng Guo School of Mechanical Electronic and Control EngineeringBeijing Jiaotong UniversityBeijing 100044China guangdong Provincial key Lab of Robotics and intelligent system Shenzhen Institute of Advanced TechnologyChinese Academy of SciencesShenzhen 518005China

Continuum robots actuated by flexible rods have large potential applications,such as detection and operation tasks in confined environments,since the push and pull actuation of flexible rods withstand tension and compressive force,and increase the structure's *** this paper,a generalized kinetostatics model for multi-module and multi-segment continuum robots considering the effect of friction based on the Cosserat rod theory is ***,the model is applied to a two-module rod-driven continuum robot with winding ropes to analyze its deformation and load *** different in-plane configurations under the external load term as S1,S2,C1,and C2 are *** a bending plane as an example,the tip deformation along thex-axis of these shapes is simulated and compared,which shows that the load capacity of C1 and C2 is generally larger than that of S1 and ***,the deformation experiments and simulations show that the maximum error ratio without external loads relative to the total length is no more than 3%,and it is no more than 4.7%under the external *** established kinetostatics model is proven sufficient to accurately analyze the rod-driven continuum robot with the consideration of internal friction.

关键词： Rod-driven continuum robot Kinetostatic model Cosserat rod theory Deformation and stiffness analysis

Research on the Method of Heat Preservation and Heating for the Drilling system of Polar Offshore Drilling Platform

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Energy Engineering 2024年第5期121卷 1173-1193页

作者： Yingkai Dong Chaohe Chen Guangyan Jia Lidai Wang Jian Bai Oil and Gas Research and Development Center CIMC RAFFLESYantai264000China School of Civil Engineering and transportation South China University of TechnologyGuangzhou510641China Yantai Hangxiao Steel Structure Assembly Construction Co. Ltd.Yantai264000China

This study investigates the heat dissipation mechanism of the insulation layer and other plane insulation layers in the polar drilling rig *** the basic theory of heat transfer with the environmental requirements of polar drilling operations and the characteristics of polar drilling processes,we analyze the factors that affect the insulation effect of the drilling rig *** factors include the thermal conductivity of the insulation material,the thickness of the insulation layer,ambient temperature,and wind *** optimize the thermal insulation material of the polar drilling rig system using a steady-state method to measure solid thermal *** analyzing the distribution of temperature in space after heating,we optimize the distribution and air outlet angle of the heater using Fluent hydrodynamics *** results demonstrate that under polar conditions,polyisocyanurate with stable thermodynamic properties is selected as the thermal insulation *** selection of thermal insulation material and thickness significantly affects the thermal insulation effect of the system but has little effect on its heating ***,when the air outlet angle of the heater is set to 32.5°,the heating efficiency of the system can be effectively *** to heat transfer equations and heat balance theory,we determine that the heating power required for the system to reach 5°C is close to numerical simulation.

关键词： Polar drilling drilling system fluid dynamics heat preservation and heating numerical simulation

Type Synthesis of Self-Alignment Parallel Ankle Rehabilitation Robot with Suitable Passive Degrees of Freedom

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Chinese Journal of Mechanical Engineering 2024年第1期37卷 160-175页

作者： Ya Liu Wenjuan Lu Dabao Fan Weijian Tan Bo Hu Daxing Zeng School of Mechanical Engineering Yanshan UniversityQinhuangdao 066004China School of Mechanical Engineering Dongguan University of TechnologyDongguan 523808China Dongguan Engineering Technology Research Center for Parallel Robot Dongguan 523808China The DGUT Innovation Center of Robotics and intelligent Equipment Dongguan 523808China

The current parallel ankle rehabilitation robot(ARR)suffers from the problem of difficult real-time alignment of the human-robot joint center of rotation,which may lead to secondary injuries to the *** study investigates type synthesis of a parallel self-alignment ankle rehabilitation robot(PSAARR)based on the kinematic characteristics of ankle joint rotation center drift from the perspective of introducing"suitable passive degrees of freedom(DOF)"with a suitable number and ***,the self-alignment principle of parallel ARR was proposed by deriving conditions for transforming a human-robot closed chain(HRCC)formed by an ARR and human body into a kinematic suitable constrained system and introducing conditions of"decoupled"and"less limb".Second,the relationship between the self-alignment principle and actuation wrenches(twists)of PSAARR was analyzed with the velocity Jacobian matrix as a"bridge".Subsequently,the type synthesis conditions of PSAARR were ***,a PSAARR synthesis method was proposed based on the screw theory and type of PSAARR synthesis ***,an HRCC kinematic model was established to verify the self-alignment capability of the *** this study,93 types of PSAARR limb structures were synthesized and the self-alignment capability of a human-robot joint axis was verified through kinematic analysis,which provides a theoretical basis for the design of such an ARR.

关键词： Ankle rehabilitation robot Self-alignment Parallel mechanism Type synthesis Screw theory

Hierarchical Sponge-Hydrogel Hybrid Structures with Robust Interfaces

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Chinese Journal of Chemistry 2023年第20期41卷 2635-2640页

作者： Pei Zhang Guangda Chen Xingmei Chen Junfei Xing Yue Tao Ji Liu Department of Mechanical and Energy Engineering Southern University of Science and TechnologyShenzhenGuangdong518055 China Shenzhen key laboratory of Biomimetic Robotics and intelligent systems Department of Mechanical and Energy EngineeringSouthern University of Science and TechnologyShenzhenGuangdong518055 China guangdong Provincial key laboratory of Human-Augmentation and Rehabilitation Robotics in Universities Southern University of Science and TechnologyShenzhenGuangdong518055 China

Soft materials including elastomers and hydrogels are playing critical roles in a variety of fields,including bioelectrodes,batteries,supercapacitors,biomedical scaffolds,and solar vapor *** hydrophobic sponges(i.e.,mechanical robustness,elasticity and macroscopic porous structure)and hydrophilic hydrogels(i.e.,autonomous water absorption and transportation,biocompatibility)within one unit could readily combine the complementary characters from each component,making a number of future research directions and applications *** propose a simple yet effective strategy to construct sponge-hydrogel hybrid structures with robust hydrophobic-hydrophilic *** sponge scaffold imparts the sponges-hydrogel hybrids with desirable mechanical robustness,elasticity and macroscopic *** the other hand,the incorporated hydrogel component endows the hybrids with high water content(98 wt%hydrogel and 2 wt%sponge),superior compatibility,and nanoscale pores allowing for storage and transportation of various chemical and biological *** further demonstrate that the introduction of hydrophilic hydrogel components could effectively improve the liquid absorption capability,blood coagulation rate,hemostatic capacity and hemocompatibility,thus promising as hemostatic agents.

关键词： Sponge-hydrogel hybrid Interface Hierarchical Robustness Liquid absorption Gels Polymer Composites Materials Science

Passivation of degradation path enables high performance perovskite nanoplatelet lasers with high operational stability

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Photonics Research 2022年第6期10卷 1440-1452页

作者： GUOHUI LI HUIHUI PI YANFU WEI BOLIN ZHOU YA GAO RONG WEN YUYING HAO HAN ZHANG BENG S.ONG YANXIA CUI College of Physics and Optoelectronics Key Laboratory of Interface Science and Engineering in Advanced MaterialsKey Laboratory of Advanced Transducers and Intelligent Control System of Ministry of EducationTaiyuan University of TechnologyTaiyuan 030024China Collaborative Innovation Centre for Optoelectronic Science and Technology Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong ProvinceCollege of Physics and Optoelectronic EngineeringShenzhen Key Laboratory of Micro-Nano Photonic Information TechnologyGuangdong Laboratory of Artificial Intelligence and Digital Economy(SZ)Shenzhen UniversityShenzhen 518060China Department of Chemistry Research Centre of Excellence for Organic ElectronicsInstitute of Advanced MaterialsHong Kong Baptist UniversityKowloon TongHong KongChina

MAPbI_(3)perovskite has attracted widespread interests for developing low-cost near infrared semiconductor gain ***,it faces the instability issue under operation conditions,which remains a critical *** is found that the instability of the MAPbI_(3)nanoplatelet laser comes from the thermal-induced degradation progressing from the surface defects towards neighboring *** using PbI_(2) passivation,the defect-initiated degradation is significantly suppressed and the nanoplatelet degrades in a layer-by-layer way,enabling the MAPbI_(3)laser to sustain for 4500 s(2.7×10^(7) pulses),which is nearly three times longer than that of the nanoplatelet laser without ***,the PbI_(2) passivated MAPbI_(3)nanoplatelet laser with the nanoplatelet cavity displays a maximum quality factor up to∼7800,the highest reported for all MAPbI_(3)nanoplatelet ***,a high stability MAPbI_(3)nanoplatelet laser that can last for 8500 s(5.1×10^(7) pulses)is demonstrated based on a dual passivation strategy,by retarding the defect-initiated degradation and surface-initiated degradation *** work provides in-depth insights for understanding the operating degradation of perovskite lasers,and the dual passivation strategy paves the way for developing high stability near infrared semiconductor laser media.

关键词： stability initiated high

Sensor-guided gait-synchronization lower-extremity-exoskeleton for potential application on unilateral knee-injured people

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Frontiers of Information Technology & Electronic Engineering 2022年第6期23卷 920-936页

作者： Donghai WANG State key laboratory of Digital Manufacturing Equipmen and Technology Huazhong University of Seience and Technology Wuhan 430074China guangdong Sygole intelligent Technology Co. Ltd.Dongguan 523808China

This paper presents a sensor-guided gait-synchronization system to help potential unilateral knee-injured people walk normally with a weight-supported lower-extremity-exoskeleton(LEE).This relieves the body weight loading on the knee-injured leg and synchronizes its motion with that of the healthy leg during the swing phase of *** sensor-guided gait-synchronization system is integrated with a body sensor network designed to sense the motion/gait of the healthy *** by the measured joint-angle trajectories,the motorized hip joint lifts the links during walking and synchronizes the knee-injured gait with the healthy gait by a half-cycle *** effectiveness of the LEE is illustrated *** compare the measured joint-angle trajectories between the healthy and knee-injured legs,the simulated knee forces,and the human-exoskeleton interaction *** results indicate that the motorized hip-controlled LEE can synchronize the motion/gait of the combined body-weight-supported LEE and injured leg with that of the healthy leg.

关键词： Sensor-guided Lower-extremity-exoskeleton Body sensor network Gait synchronization Weight-support