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Dissipative microwave photonic solitons in spontaneous frequency-hopping optoelectronic oscillators

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Photonics Research 2022年第5期10卷 1280-1289页

作者： tengfei hao hao DING WEI LI NINGHUA ZHU YITANG DAI MING LI State Key Laboratory on Integrated Optoelectronics Institute of SemiconductorsChinese Academy of SciencesBeijing 100083China School of Electronic Electrical and Communication EngineeringUniversity of Chinese Academy of SciencesBeijing 100049China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100190China State Key Laboratory of Information Photonics and Optical Communications Beijing University of Posts and TelecommunicationsBeijing 100876China Peng Cheng Laboratory Shenzhen 518052China

Dissipative solitons relying on the double balance between nonlinear and linear effects as well as cavity loss and gain have attracted increasing attention in recent years,since they give rise to novel operating states of various dissipative nonlinear *** optoelectronic oscillator(OEO)is a dissipative nonlinear microwave photonic system with a high quality factor that has been widely investigated for generating ultra-low noise single-frequency microwave ***,we report a novel operating state of an OEO related to dissipative solitons,i.e.,spontaneous frequency hopping related to the formation of dissipative microwave photonic *** this operating state,dissipative microwave photonic solitons occur due to the double balance between nonlinear gain saturation and linear filtering as well as cavity loss and gain in the OEO cavity,creating spontaneous frequencyhopping microwave *** generation of wideband tunable frequency-hopping microwave signals with a fast frequency-hopping speed up to tens of nanoseconds is observed in the experiment,together with the corresponding soliton *** work reveals a novel mechanism between the interaction of nonlinear and linear effects in an OEO cavity,extends the suitability and potential applications of solitons,and paves the way for a new class of soliton microwave photonic systems for the generation,processing,and control of microwave and RF signals.

关键词： microwave solitons dissipative

钢框架岩棉夹芯板超高防火隔墙耐火与稳定性能研究

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消防科学与技术 2024年第8期43卷 1105-1110页

作者：郝腾飞赵东拂李磊王长辉符演北京建筑大学土木与交通工程学院北京100044 中国建筑科学研究院有限公司北京100013 北京未来城市设计高精尖创新中心北京100044 北京建筑大学大型多功能振动台阵实验室北京100044 北京建筑大学北京节能减排与城乡可持续发展省部共建协同创新中心北京100044 工程结构与新材料北京市高等学校工程研究中心北京100044

为满足大型厂房对轻质超高防火隔墙的需求,提出了一种钢框架岩棉夹芯板超高防火隔墙,并对其耐火性与稳定性进行研究。采用ISO-834标准升温曲线的加热方法,对缩尺比例为1∶0.3岩棉夹芯板防火隔墙进行单面受火试验。并基于有限元软件ABAQU... 详细信息

为满足大型厂房对轻质超高防火隔墙的需求,提出了一种钢框架岩棉夹芯板超高防火隔墙,并对其耐火性与稳定性进行研究。采用ISO-834标准升温曲线的加热方法,对缩尺比例为1∶0.3岩棉夹芯板防火隔墙进行单面受火试验。并基于有限元软件ABAQUS建立缩尺模型与足尺模型,研究了防火隔墙防火优化前后两种方案下受火面与背火面的温度场变化规律。结果表明:缩尺试验模型与缩尺有限元模型的温度和形变基本吻合;足尺有限元模型的岩棉夹芯板超高防火隔墙在防火优化后,背火面最高温度降低,最大形变降低了75.5%,耐火性与稳定性得到大幅改善,并满足《建筑构件耐火试验方法》对于防火隔墙隔热性和完整性要求。在防火隔墙设计方面,容重为50 kg/m^(2)的钢框架岩棉夹芯板超高防火隔墙,跨度方向每8 m需设一根钢柱,高度方向每3.6 m需设一根钢梁。

关键词：轻质超高防火隔墙有限元分析温度场规律形心位移

Optoelectronic parametric oscillator

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Light(Science & Applications) 2020年第1期9卷 1028-1037页

作者： tengfei hao Qizhuang Cen Shanhong Guan Wei Li Yitang Dai Ninghua Zhu Ming Li State Key Laboratory on Integrated Optoelectronics Institute of SemiconductorsChinese Academy of SciencesBeijing 100083China School of Electronic Electrical and Communication EngineeringUniversity of Chinese Academy of SciencesBeijing 100049China State Key Laboratory of Information Photonics and Optical Communications Beijing University of Posts and TelecommunicationsBeijing 100876China

Oscillators are one of the key elements in various applications as a signal source to generate periodic *** them,an optical parametric oscillator(OPO)is a driven harmonic oscillator based on parametric frequency conversion in an optical cavity,which has been widely investigated as a coherent light source with an extremely wide wavelength tuning ***,steady oscillation in an OPO is confined by the cavity delay,which leads to difficulty in frequency tuning,and the frequency tuning is discrete with the minimum tuning step determined by the cavity ***,we propose and demonstrate a counterpart of an OPO in the optoelectronic domain,i.e.,an optoelectronic parametric oscillator(OEPO)based on parametric frequency conversion in an optoelectronic cavity to generate microwave *** to the unique energy-transition process in the optoelectronic cavity,the phase evolution in the OEPO is not linear,leading to steady single-mode oscillation or multimode oscillation that is not bounded by the cavity ***,the multimode oscillation in the OEPO is stable and easy to realize owing to the phase control of the parametric frequency-conversion process in the optoelectronic cavity,while stable multimode oscillation is difficult to achieve in conventional oscillators such as an optoelectronic oscillator(OEO)or an OPO due to the mode-hopping and mode-competition *** proposed OEPO has great potential in applications such as microwave signal generation,oscillator-based computation,and radio-frequency phase-stable transfer.

关键词： effect oscillator parametric

MiniLap辅助两穿刺孔腹腔镜全腹膜外腹股沟疝修补术10例分析

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中华疝和腹壁外科杂志（电子版） 2024年第1期18卷 97-101页

作者：吴恺明郝腾飞张庆元中山大学附属第七医院消化医学中心广东深圳518107

目的介绍使用MiniLap辅助两穿刺孔腹腔镜全腹膜外腹股沟疝修补术(MaDP TEP)的临床优势。方法回顾性分析2022年6—10月于中山大学附属第七医院消化医学中心疝与腹壁外科专业组行MaDP TEP 10例患者的临床资料。10 mm腹腔镜穿刺孔、5 mm操... 详细信息

目的介绍使用MiniLap辅助两穿刺孔腹腔镜全腹膜外腹股沟疝修补术(MaDP TEP)的临床优势。方法回顾性分析2022年6—10月于中山大学附属第七医院消化医学中心疝与腹壁外科专业组行MaDP TEP 10例患者的临床资料。10 mm腹腔镜穿刺孔、5 mm操作穿刺孔、MiniLap参考全腹膜外腹股沟疝修补术(TEP)三穿刺孔中侧法布局。使用MiniLap无需做线性切口,经1 mm皮肤开口即可穿刺置入术区。分析患者一般资料,记录术后第1天疼痛数字评定量表(NRS)评分、手术部位感染率、疝复发率、术后3周两穿刺孔和MiniLap处瘢痕SCAR评分、单侧疝分离操作时间(即除外放置补片的手术时间)。结果10例患者中,男性9例,女性1例;年龄45~70岁,平均52.3岁;包含Rutkow(改良Gilbert分型)Ⅰ、Ⅱ、Ⅲ、Ⅴ、Ⅵ型。10例患者均成功实施MaDP TEP,术中无血管损伤,无中转开放手术。术后第1天疼痛NRS评分(1.50±0.53)分。随访1~19周,无手术部位感染,无疝复发。术后3周10 mm穿刺孔、5 mm穿刺孔和MiniLap处瘢痕SCAR评分分别为(5.10±1.25)分、(3.75±0.79)分和(1.80±0.70)分,瘢痕评分比较差异有统计学意义(P<0.01)。10例手术单侧疝分离操作时间:第1~5例(47.8±12.0)min,第6~10例患者(30.8±5.3)min,差异有统计学意义(P=0.02)。结论MaDP TEP安全有效,疼痛轻、美容减创效果好,与三穿刺孔TEP技术接近,学习曲线短,便于临床推广。

关键词： MiniLap 疝,腹股沟完全腹膜外疝修补术腹腔镜

基于改进SSD神经网络和点云配准算法的变电站三维模型快速建立方法

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武汉大学学报（工学版） 2024年第3期57卷 356-362页

作者：薛江郭建龙冯伟夏郝腾飞王永纯陈海彪周青云广东电网有限责任公司培训与评价中心广东广州510520 广东电网有限责任公司汕尾供电局广东汕尾516600

为提高变电站三维建模的效率,提出了一种改进SSD(single shot detection)目标检测算法和ICP(iterative closest point)点云配准算法结合的变电站三维模型快速建立方法。该方法针对变电设备点云训练样本数量不足造成的设备识别准确率低... 详细信息

为提高变电站三维建模的效率,提出了一种改进SSD(single shot detection)目标检测算法和ICP(iterative closest point)点云配准算法结合的变电站三维模型快速建立方法。该方法针对变电设备点云训练样本数量不足造成的设备识别准确率低这一问题,将三维模型快速建模转换为设备类型、型号识别和点云导入。首先利用改进SSD目标检测算法对变电设备类型进行初步识别,然后运用ICP配准算法对变电设备进行型号识别,2种方法的结合实现了变电设备点云的准确识别,最后根据配准得到的设备在变电站点云场景中的实际位姿,将模型库中配准的标准模型导入变电站三维点云场景,极大地提高了变电站三维模型的建模效率。该方法已在某变电站三维建模中得到应用,结果表明,不同变电设备型号识别准确率较高,设备建模平均时间为32 s,效率远远高于人工建模。

关键词：变电站建模点云场景点云配准神经网络

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某火箭发射塔试验台承力架防火保护研究

建筑科学 2024年第5期40卷 21-29页

作者：王长辉赵东拂李磊詹子娜刘栋栋郝腾飞魏晓莉北京建筑大学土木与交通工程学院北京100044 中国建筑科学研究院有限公司北京100013 工程结构与新材料北京市高等学校工程研究中心北京100044 北京未来城市设计高精尖创新中心北京100044 北京建筑大学大型多功能振动台阵实验室北京100044 北京建筑大学北京节能减排与城乡可持续发展省部共建协同创新中心北京100044

某火箭发射塔试验台钢承力架除了承受上部火箭发射试验时施加的荷载外,还会受到火箭尾部火焰的高温烧蚀作用,对承力架的安全性和耐久性亟待探究。对涂有耐高温耐烧蚀防火涂料的Q345-D钢板进行斜向喷火缩尺试验,得到其烧蚀现象、烧蚀率... 详细信息

某火箭发射塔试验台钢承力架除了承受上部火箭发射试验时施加的荷载外,还会受到火箭尾部火焰的高温烧蚀作用,对承力架的安全性和耐久性亟待探究。对涂有耐高温耐烧蚀防火涂料的Q345-D钢板进行斜向喷火缩尺试验,得到其烧蚀现象、烧蚀率及温度数据;使用FLUENT软件对缩尺模型开展流-固-热耦合数值模拟,其温度及烧蚀率与试验数据符合良好,温度最大误差为8.9%,烧蚀率最大误差为7.14%;利用上述方法对三喷管火箭发射试验过程进行模拟,得到不同喷淋量、不同防火涂料喷涂厚度工况下承力架的表面温度和塔架空间温度及速度流场分布。结果表明:缩尺试验中耐高温耐烧蚀防火涂料具有良好的隔热性能和耐烧蚀性能;温度曲线呈现明显的4个阶段:迅速升温阶段、降温阶段、逐渐回升阶段、稳定阶段;当冷却喷淋量为1m3/s时,承力架表面该防火涂料厚度不应低于15mm,喷淋量在此基础上每增加0.5m3/s,该防火涂料最小厚度可减小5.2mm,当喷淋量高于2.5m3/s,承力架则无需喷涂防火涂料。

关键词：数值模拟发射塔承力架温度场流-固-热耦合烧蚀率

A coordinated operation method of wind-PV-hydrogenstorage multi-agent energy system

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Global Energy Interconnection 2024年第4期7卷 446-461页

作者： tengfei Ma Wei Pei Yanhong Yang hao Xiao Chenghong Tang Weiqi Hua Institute of Electrical Engineering of Chinese Academy of Sciences Beijing 100190P.R.China State Grid Electric Power Research Institute Nanjing 211103P.R.China Department of Electronic Electrical and Systems EngineeringUniversity of BirminghamBirmingham B152TTUK

Wind-photovoltaic(PV)-hydrogen-storage multi-agent energy systems are expected to play an important role in promoting renewable power utilization and *** this study,a coordinated operation method was proposed for a wind-PVhydrogen-storage multi-agent energy ***,a coordinated operation model was formulated for each agent considering peer-to-peer power ***,a coordinated operation interactive framework for a multi-agent energy system was proposed based on the theory of the alternating direction method of ***,a distributed interactive algorithm was proposed to protect the privacy of each agent and solve coordinated operation ***,the effectiveness of the proposed coordinated operation method was tested on multi-agent energy systems with different structures,and the operational revenues of the wind power,PV,hydrogen,and energy storage agents of the proposed coordinated operation model were improved by approximately 59.19%,233.28%,16.75%,and 145.56%,respectively,compared with the independent operation model.

关键词： Wind-PV-hydrogen-storage Multi-agent energy system Renewable power to hydrogen Coordinated operation Peer-to-peer power trading

Recent advances in optoelectronic oscillators

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Advanced Photonics 2020年第4期2卷 4-23页

作者： tengfei hao Yanzhong Liu Jian Tang Qizhuang Cen Wei Li Ninghua Zhu Yitang Dai JoséCapmany Jianping Yao Ming Li Chinese Academy of Sciences Institute of SemiconductorsState Key Laboratory on Integrated OptoelectronicsBeijingChina University of Chinese Academy of Sciences School of ElectronicElectricaland Communication EngineeringBeijingChina University of Chinese Academy of Sciences Center of Materials Science and Optoelectronics EngineeringBeijingChina Beijing University of Posts and Telecommunications State Key Laboratory of Information Photonics and Optical CommunicationsBeijingChina Universitat Politécnica de Valencia ITEAM Research InstitutePhotonics Research LabsValenciaSpain University of Ottawa Microwave Photonics Research LaboratoryOttawaOntarioCanada

An optoelectronic oscillator(OEO)is a microwave photonic system that produces microwave signals with ultralow phase noise using a high-quality-factor optical energy storage *** type of oscillator is desired in various practical applications,such as communication links,signal processing,radar,metrology,radio astronomy,and reference clock ***,new mode control and selection methods based on Fourier domain mode-locking and parity-time symmetry have been proposed and experimentally demonstrated in OEOs,which overcomes the long-existing mode building time and mode selection problems in a traditional *** to these mode control and selection methods,continuously chirped microwave waveforms can be generated directly from the OEO cavity and single-mode operation can be achieved without the need of ultranarrowband filters,which are not possible in a traditional *** OEOs with a compact size and low power consumption have also been demonstrated,which are key steps toward a new generation of compact and versatile OEOs for demanding *** review recent progress in the field of OEOs,with particular attention to new mode control and selection methods,as well as chip-scale integration of OEOs.

关键词： optoelectronic oscillator microwave photonics Fourier domain mode-locking parity-time symmetry photonics integrated circuits

Single-photon microwave photonics

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Science Bulletin 2022年第7期67卷 700-706页

作者： Ye Yang Yaqing Jin Xiao Xiang tengfei hao Wei Li Tao Liu Shougang Zhang Ninghua Zhu Ruifang Dong Ming Li State Key Laboratory on Integrated Optoelectronics Institute of SemiconductorsChinese Academy of SciencesBeijing 100083China Key Laboratory of Time and Frequency Primary Standards National Time Service CenterChinese Academy of SciencesXi’an 710600China School of Electronic Electrical and Communication EngineeringUniversity of Chinese Academy of SciencesBeijing 100049China School of Astronomy and Space Science University of Chinese Academy of SciencesBeijing 100049China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100190China

With the rapid development of microwave photonics technology, high-speed processing and ultra-weak signal detection capability have become the main bottlenecks in many applications. Thanks to the ultraweak signal detection capability and the extremely low timing jitter properties of single-photon detectors, the combination of single-photon detection and classical microwave photonics technology may provide a solution to break the above bottlenecks. In this paper, we first report a novel concept of singlephoton microwave photonics(SP-MWP), a SP-MWP signal processing system with phase shifting and frequency filtering functionalities is demonstrated based on a superconducting nanowire single photon detector(SNSPD) and a successive time-correlated single photon counting(TCSPC) *** results show that an ultrahigh optical sensitivity down to-100 d Bm has been achieved,and the signal processing bandwidth is only limited by the timing jitter of single-photon detectors. In the meantime, the proposed system demonstrates an ultrahigh anti-interference capability, only the signal which is phase locked by the trigger signal in TCSPC can be extracted from the detected signals combining with noise and strong interference. The proposed SP-MWP concept paves a way to a novel interdisciplinary field of microwave photonics and quantum mechanism, named by quantum microwave photonics.

关键词： Single photon Quantum microwave photonic High-speed signal processing Time-correlated single photon counting