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Ultracompact silicon on-chip polarization controller

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Photonics Research 2024年第2期12卷 183-193页

作者： WEIKE ZHAO YINGYING PENG MINGYU ZHU RUORAN LIU XIAOLONG HU YAOCHENG SHI DAOXIN DAI State Key Laboratory for Modern Optical Instrumentation Center for Optical&Electromagnetic ResearchCollege of Optical Science and EngineeringInternational Research Center for Advanced PhotonicsZhejiang UniversityZijingang CampusHangzhou 310058China school of Precision Instrument and Optoelectronic engineering Tianjin UniversityTianjin 300072China Key Laboratory of Optoelectronic Information Science and Technology Ministry of EducationTianjin 300072China Ningbo Research Institute Zhejiang UniversityNingbo 315100China

On-chip polarization controllers are extremely important for various optical systems.In this paper,a compact and robust silicon-based on-chip polarization controller is proposed and demonstrated by integrating a special polarization converter and phase shifters.The special polarization converter consists of a 1×1 Mach–Zehnder interferometer with two polarization-dependent mode converters at the input/output ends.When light with an arbitrary state of polarization(SOP)is launched into the chip,the TE_(0)and TM_(0)modes are simultaneously excited.The polarization extinction ratio(PER)and the phase difference for the TE_(0)∕TM_(0)modes are tuned by controlling the first phase shifter,the polarization converter,and the second phase shifter.As a result,one can reconstruct the light SOP at the output port.The fabricated polarization controller,as compact as~150μm×700μm,exhibits an excess loss of less than 1 dB and a record PER range of>54 dB for arbitrary input light beams in the wavelength range of 1530–1620 nm.

关键词： polarization SOP interferometer

Laser Powder Bed Fusion of Beta-Type Titanium Alloys for Biomedical Application:A Review

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Acta Metallurgica Sinica(English Letters) 2024年第1期37卷 17-28页

作者： Xuan Luo Chao Yang Dongdong Li Lai-Chang Zhang State Key Laboratory of Materials Processing and Die&Mould Technology Huazhong University of Science and TechnologyWuhan430074China National engineering Research Center of Near-Net-Shape Forming for Metallic Materials Guangdong Provincial Key Laboratory for Processing and Forming of Advanced Metallic MaterialsSouth China University of TechnologyGuangzhou510640China Centre for Advanced Materials and Manufacturing School of EngineeringEdith Cowan University270 Joondalup DriveJoondalupPerthWA6027Australia

Additive manufacturing ofβ-type titanium alloy is expected to replace Ti-6Al-4V alloy in the field of orthopedic implantation because of their low elastic modulus,excellent corrosion resistance,and biocompatibility.After briefly introducing the laser powder bed fusion(LPBF)process and physical phenomena,this paper reviews the recent progresses in LPBF-edβ-type Ti alloys.The strategies to strengthening and tougheningβ-type Ti alloys are critically reviewed.This is followed by the processing routes employed to achieve to low modulus for orthopedic applications,especially a new methodology for tailoring crystallographic orientation called multi-track coupled directional solidification.The effect of processing and compositions on performance metrics ofβ-type Ti alloys included corrosion behavior,and biocompatibility is reviewed.In the end,challenges in additive manufacturing ofβ-type Ti alloys in future are highlighted,with the aim to ensue clinical application of LPBF-edβ-type Ti alloys.

关键词： β-type Ti alloys Laser powder bed fusion Mechanical properties Elastic modulus Biocompatibility

Frequency-dependent Electrical Capacitance and Resistance of Ultra-high Performance Concrete and Their Responses to Compressive Strain

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Journal of Wuhan University of Technology(Materials Science) 2024年第4期39卷 968-978页

作者：吴瑜孙明清 ZHU Lutao SONG Qiulei CHEN Jianzhong Hubei Key Laboratory of Theory and Application of Advanced Materials Mechanics School of ScienceWuhan University of TechnologyWuhan 430070China school of Civil engineering and Architecture Hubei University of Arts and ScienceXiangyang 441053China Suzhou Concrete and Cement Products Research Institude Co. LtdSuzhou 215026China

The frequency-dependent electrical properties and strain self-sensing behaviour of ultra-high performance concrete(UHPC)as cement-based stress/strain self-sensing(CBSS)smart materials were investigated in the frequency range from 100 Hz to 300 kHz.By using the electrical parameters of the equivalent electric circuit model,the quantitative relations of capacitance and conductance of CBSS with the measurement frequency were derived.The capacitance and the conductance exhibit power-law type dependence on the measurement frequency.The calculated capacitance values at frequencies beyond 2 kHz and conductance values are consistent with the experimental results.The sweep-frequency test and the fixed-frequency test were performed to examine effects of the excitation frequencies on strain self-sensing properties of CBSS.The fractional change in capacitance(FCC)and resistance(FCR)of CBSS are frequency-dependent in the frequency range from 100 Hz to the f_(B),but frequency-independent in the frequency range from the f_(B)to 300 kHz.The f_(A)and the f_(B)are 1.7-4.0 kHz and 11-78 kHz depending on the fiber dosages,respectively.FCC and FCR reach their maximum at the f_(A)and 100 Hz,respectively.The responses of capacitance and resistance of CBSS to strain show good repeatability during cyclic loading.As the fiber dosage increases,capacitance-based sensitivity to strain increases initially and then decreases at the f_(A),and resistance-based sensitivity to strain of CBSS increases with increasing fiber contents.

关键词： UHPC strain self-sensing capacitance-based frequency-dependent

Analytical solutions of turbulent boundary layer beneath forward-leaning waves

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Applied Mathematics and Mechanics(English Edition) 2024年第4期45卷 695-710页

作者： Yiqin XIE Jifu ZHOU Xu WANG Jinlong DUAN Yongjun LU Shouqian LI Laboratory for Mechanics in Fluid Solid Coupling Systems Institute of MechanicsChinese Academy of SciencesBeijing 100190China State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin China Institute of Water Resources and Hydropower ResearchBeijing 100038China school of engineering Sciences University of Chinese Academy of SciencesBeijing 100049China State Key Laboratory of Hydrology-Water Resources and Hydraulic engineering Nanjing Hydraulic Research InstituteNanjing 210024China

As a typical nonlinear wave,forward-leaning waves can be frequently encountered in the near-shore areas,which can impact coastal sediment transport significantly.Hence,it is of significance to describe the characteristics of the boundary layer beneath forward-leaning waves accurately,especially for the turbulent boundary layer.In this work,the linearized turbulent boundary layer model with a linear turbulent viscosity coefficient is applied,and the novel expression of the near-bed orbital velocity that has been worked out by the authors for forward-leaning waves of arbitrary forward-leaning degrees is further used to specify the free stream boundary condition of the bottom boundary layer.Then,a variable transformation is found so as to make the equation of the turbulent boundary layer model be solved analytically through a modified Bessel function.Consequently,an explicit analytical solution of the turbulent boundary layer beneath forward-leaning waves is derived by means of variable separation and variable transformation.The analytical solutions of the velocity profile and bottom shear stress of the turbulent boundary layer beneath forward-leaning waves are verified by comparing the present analytical results with typical experimental data available in the previous literature.

关键词： forward-leaning wave turbulent boundary layer velocity profile bottom shear stress

Tube-based Model Reference Adaptive Control for Vibration Suppression of Active Suspension Systems

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IEEE/CAA Journal of Automatica Sinica 2022年第4期9卷 728-731页

作者： Yashar Mousavi Alireza Alfi Ibrahim Beklan Kucukdemiral Afef Fekih IEEE the Department of Applied Science School of ComputingEngineering and Built EnvironmentGlasgow Caledonian University the Faculty of Electrical engineering Shahrood University of Technology the Electrical and Computer engineering Department University of Louisiana at Lafayette

Dear editor,With the developments of industrial automation in recent years,vehicle suspension systems have received a great deal of attention in industry and academia due to their critical role in the chassis performance of vehicles[1].The suspension system is expected to guarantee the vehicle’s maneuverability and provide satisfactory ride comfort by absorbing the vibrations arising from the road surface excitations and ensuring road-holding capability and suspension safety.Motivated by the desirable performance of the model reference adaptive control(MRAC)approach,various literature studies have investigated its performance in diverse linear and nonlinear practical systems[2].

关键词： editor Active guarantee

仿DNase酶的双金属分级多孔MOFs:制备与抗细菌生物膜应用

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Science China Materials 2024年第1期67卷 343-354页

作者：夏凡李可杨健陈婧雯刘熙濛龚鸣顾金楼 Key Laboratory for Ultrafine Materials of Ministry of Education School of Materials Science and EngineeringEast China University of Science and TechnologyShanghai 200237China

本研究成功构建了具有切割DNA能力的双金属枝状大孔金属有机框架(MOFs;HMUiO-66(Zr/Ce)),并将其用于高效破坏生物膜并抑制细菌生长.通过改变Zr/Ce的投料比,可在0-69%的范围内精确调控Zr/Ce的引入量,并控制其粒径在1μm-150 nm之间.HMUiO... 详细信息

本研究成功构建了具有切割DNA能力的双金属枝状大孔金属有机框架(MOFs;HMUiO-66(Zr/Ce)),并将其用于高效破坏生物膜并抑制细菌生长.通过改变Zr/Ce的投料比,可在0-69%的范围内精确调控Zr/Ce的引入量,并控制其粒径在1μm-150 nm之间.HMUiO-66(Zr/Ce)具有独特的化学和热稳定性,开放的大孔结构和可接近的Lewis酸活性位点,表现出模拟DNA酶活性.双金属MOFs中丰富的Zr-OH位点能有效地捕获核酸,而相邻的Ce-OH基团对磷氧键形成亲核攻击,协同放大DNA的水解速率,使得开发的HMUiO-66(Zr/Ce)能够作为切割细胞外DNA和清除细菌生物膜的纳米药物.在此基础上,我们设计了一种仿生HMUiO-66(Zr/Ce)/PVDF膜,该生物膜可抑制细菌粘附和定植,在抗菌治疗和医疗器械中具有广阔的应用前景.

关键词：金属有机框架细菌生物膜双金属医疗器械水解速率细菌粘附 PVDF膜大孔结构

IR-YOLO: Real-Time Infrared Vehicle and Pedestrian Detection

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Computers, Materials & Continua 2024年第2期78卷 2667-2687页

作者： Xiao Luo Hao Zhu Zhenli Zhang Department of Electrical engineering and Automation Jiangxi University of Science and TechnologyGanzhou341000China Jiangxi Provincial Key Laboratory of Maglev Technology Ganzhou341000China Graduate school of Information Production and SystemsWaseda UniversityKitakyushu-shiFukuoka808-0135Japan

Road traffic safety can decrease when drivers drive in a low-visibility environment.The application of visual perception technology to detect vehicles and pedestrians in infrared images proves to be an effective means of reducing the risk of accidents.To tackle the challenges posed by the low recognition accuracy and the substan-tial computational burden associated with current infrared pedestrian-vehicle detection methods,an infrared pedestrian-vehicle detection method A proposal is presented,based on an enhanced version of You Only Look Once version 5(YOLOv5).First,A head specifically designed for detecting small targets has been integrated into the model to make full use of shallow feature information to enhance the accuracy in detecting small targets.Second,the Focal Generalized Intersection over Union(GIoU)is employed as an alternative to the original loss function to address issues related to target overlap and category imbalance.Third,the distribution shift convolution optimization feature extraction operator is used to alleviate the computational burden of the model without significantly compromising detection accuracy.The test results of the improved algorithm show that its average accuracy(mAP)reaches 90.1%.Specifically,the Giga Floating Point Operations Per second(GFLOPs)of the improved algorithm is only 9.1.In contrast,the improved algorithms outperformed the other algorithms on similar GFLOPs,such as YOLOv6n(11.9),YOLOv8n(8.7),YOLOv7t(13.2)and YOLOv5s(16.0).The mAPs that are 4.4%,3%,3.5%,and 1.7%greater than those of these algorithms show that the improved algorithm achieves higher accuracy in target detection tasks under similar computational resource overhead.On the other hand,compared with other algorithms such as YOLOv8l(91.1%),YOLOv6l(89.5%),YOLOv7(90.8%),and YOLOv3(90.1%),the improved algorithm needs only 5.5%,2.3%,8.6%,and 2.3%,respectively,of the GFLOPs.The improved algorithm has shown significant advancements in balancing accuracy and computational efficiency,making it promising for practica

关键词： Traffic safety infrared image pedestrians and vehicles focal GIoU distributed shift convolution

Hierarchical Spinning of Janus Textiles with Anisotropic Wettability for Wound Healing

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Research 2024年第1期2023卷 97-105页

作者： Han Zhang Lingyu Sun Jiahui Guo Yuanjin Zhao Department of Rheumatology and Immunology Nanjing Drum Tower HospitalSchool of Biological Science and Medical EngineeringSoutheast UniversityNanjingJiangsu 210096China Oujiang Laboratory(Zhejiang Lab for Regenerative Medicine Vision and Brain Health)Wenzhou InstituteUniversity of Chinese Academy of SciencesWenzhouZhejiang 325001China

Wound healing and tissue repair are recognized as basic human health problems worldwide.Attempts to accelerate the reparative process are focused on developing functional wound dressings.Herein,we present novel Janus textiles with anisotropic wettability from hierarchical microfluidic spinning for wound healing.The hydrophilic hydrogel microfibers from microfluidics are woven into textiles for freeze-drying treatment,followed by the deposition of electrostatic spinning nanofibers composed of hydrophobic polylactic acid(PLA)and silver nanoparticles.The electrospun nanofiber layer can be well coupled with the hydrogel microfiber layer to generate Janus textiles with anisotropic wettability due to the roughness of the hydrogel textile surface and the incomplete evaporation of PLA solution when reaching the surface.For wound treatment with the hydrophobic PLA side contacting the wound surface,the wound exudate can be pumped from the hydrophobic to the hydrophilic side based on the wettability differential derived drainage force.During this process,the hydrophobic side of the Janus textile can prevent excess fluid from infiltrating the wound again,preventing excessive moisture and preserving the breathability of the wound.In addition,the silver nanoparticles contained in the hydrophobic nanofibers could impart the textiles with good antibacterial effect,which further promote the wound healing efficiency.These features indicate that the described Janus fiber textile has great application potential in the field of wound treatment.

关键词： silver spinning healing

Effect of Modulus Heterogeneity on the Equilibrium Shape and Stress Field ofαPrecipitate in Ti-6Al-4V

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Computer Modeling in engineering & Sciences 2024年第7期140卷 1017-1028页

作者： Di Qiu Rongpei Shi Materials Genome Institute Shanghai UniversityShanghai200444China school of Materials Science and engineering Harbin Institute of TechnologyShenzhen518055China Shanghai Frontier Science Center of Mechanoinformatics Shanghai UniversityShanghai200444China Zhejiang Laboratory Hangzhou311100China

For media with inclusions(e.g.,precipitates,voids,reinforcements,and others),the difference in lattice parameter and the elastic modulus between the matrix and inclusions cause stress concentration at the interfaces.These stress fields depend on the inclusions’size,shape,and distribution and will respond instantly to the evolving microstructure.This study develops a phase-field model concerningmodulus heterogeneity.The effect of modulus heterogeneity on the growth process and equilibrium state of theαplate in Ti-6Al-4V during precipitation is evaluated.Theαprecipitate exhibits strong anisotropy in shape upon cooling due to the interplay of the elastic strain and interfacial energy.The calculated orientation of the habit plane using the homogeneous modulus ofαphase shows the smallest deviation fromthat of the habit plane observed in the experiment,compared to the case where the homogeneous modulus ofβphase is adopted.In addition,the equilibrium volume ofαphase within the systemusing homogeneousβmodulus exhibits the largest dependency on the applied stresses.The stress fields across theα/βinterface are further calculated under the assumption of modulus heterogeneity and compared to those using homogeneous modulus of eitherαorβphase.This study provides an essential theoretical basis for developing mechanics models concerning systems with heterogeneous structures.

关键词： Elastic heterogeneity habit plane stress field titanium phase-field simulation