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Multifunctional mixed analog/digital signal processor based on integrated photonics

Opto-Electronic Science 2024年第8期3卷 1-12页

作者： Yichen Wu Qipeng Yang Bitao Shen Yuansheng Tao Xuguang Zhang Zihan Tao Luwen Xing zhangfeng Ge Tiantian Li Bowen Bai Haowen Shu Xingjun Wang State Key Laboratory of Advanced Optical Communication Systems and Networks School of ElectronicsPeking UniversityBeijing 100871China College of Engineering Peking UniversityBeijing 100871China Peking University Yangtze Delta Institute of Optoelectronics Nantong 226010China School of Electronic Engineering Xi’an University of Posts&TelecommunicationsXi’an 710121China Frontiers Science Center for Nano-optoelectronics Peking UniversityBeijing 100871China Peng Cheng Laboratory Shenzhen 518055China

Photonic signal processing offers a versatile and promising toolkit for contemporary scenarios ranging from digital optical communication to analog microwave *** to its electronic counterpart,it eliminates inherent bandwidth limitations and meanwhile exhibits the potential to provide unparalleled scalability and flexibility,particularly through integrated ***,by far the on-chip solutions for optical signal processing are often tailored to specific tasks,which lacks versatility across diverse ***,we propose a streamlined chip-level signal processing architecture that integrates different active and passive building blocks in silicon-on-insulator(SOI)platform with a compact and efficient *** and in-depth analyses for the architecture are conducted at levels of device,system,and *** by appropriate configuring schemes,the photonic circuitry supports loading and processing both analog and digital signals *** distinct tasks are facilitated with one single chip across several mainstream fields,spanning optical computing,microwave photonics,and optical ***,it has demonstrated competitive performance in functions like image processing,spectrum filtering,and electro-optical bandwidth *** high universality and a compact form factor,the proposed architecture is poised to be instrumental for next-generation functional fusion systems.

关键词： silicon photonics multifunctional signal process microwave photonics optical computing optical communica-tion equalization

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Reliable intracavity reflection for self-injection locking lasers and microcomb generation

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Photonics Research 2024年第5期12卷 I0001-I0010页

作者： BITAO SHEN XUGUANG ZHANG YIMENG WANG ZIHAN TAO HAOWEN SHU HUAJIN CHANG WENCAN LI YAN ZHOU zhangfeng Ge RUIXUAN CHEN BOWEN BAI LIN CHANG XINGJUN WANG State Key Laboratory of Advanced Optical Communications System and Networks School of ElectronicsPeking UniversityBeijing 100871China Peng Cheng Laboratory Shenzhen 518055China Peking University Yangtze Delta Institute of Optoelectronics Nantong 226010China Frontiers Science Center for Nano-optoelectronics Peking UniversityBeijing 100871China

Self-injection locking has emerged as a crucial technique for coherent optical sources,spanning from narrow linewidth lasers to the generation of localized *** technique involves key components,namely a laser diode and a high-quality cavity that induces narrow-band reflection back into the laser ***,in prior studies,the reflection mainly relied on the random intracavity Rayleigh backscattering,rendering it unpredictable and unsuitable for large-scale production and wide-band *** this work,we present a simple approach to achieve reliable intracavity reflection for self-injection locking to address this challenge by introducing a Sagnac loop into the *** method guarantees robust reflection for every resonance within a wide operational band without compromising the quality factor or adding complexity to the fabrication *** a proof of concept,we showcase the robust generation of narrow linewidth lasers and localized microcombs locked to different resonances within a normal-dispersion ***,the existence and generation of localized patterns in a normal-dispersion cavity with broadband forward–backward field coupling is first proved,as far as we know,both in simulation and in *** research offers a transformative approach to self-injection locking and holds great potential for large-scale production.

关键词： intracavity injection locking

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长时序Sentinel-1InSAR形变监测关键算法研究

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测绘学报 2024年第2期53卷 397-397页

作者：马张烽南洋理工大学新加坡地球观测中心新加坡639798

合成孔径雷达干涉测量(interferometric synthetic aperture radar,InSAR)作为一种新兴的空间大地测量技术,能够全天候、大面积、连续、高精度、高空间分辨率地获取地表形变信息,与传统大地测量相比有效地提高了观测精度,扩大了观测范围... 详细信息

合成孔径雷达干涉测量(interferometric synthetic aperture radar,InSAR)作为一种新兴的空间大地测量技术,能够全天候、大面积、连续、高精度、高空间分辨率地获取地表形变信息,与传统大地测量相比有效地提高了观测精度,扩大了观测范围,缩短了观测周期。该技术在探索地震、火山喷发、海陆升降的成因过程与机制中有着广阔的前景。论文以当前InSAR数据处理过程中需应对大量数据为背景,提出了基于Sentinel-1双星的长时序InSAR处理流程,主要研究内容如下。

关键词：合成孔径雷达干涉测量火山喷发大地测量空间大地测量技术地表形变高空间分辨率观测范围观测精度

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离散优化框架下的多基线InSAR相位解缠方法

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测绘学报 2024年第3期53卷 473-481页

作者：岳佳伟黄其欢刘辉马张烽河海大学地球科学与工程学院江苏南京211100 华北水利水电大学测绘与地理信息学院河南郑州450046 南洋理工大学新加坡地球观象站新加坡639798

多基线相位解缠技术通过扩展InSAR干涉相位的模糊度区间,突破了单基线解缠的相位连续性限制。然而,相位噪声始终困扰着多基线解缠,聚类分析算法能够在一定程度上抑制噪声,但聚类簇边界的相位连续性难以保障。针对该问题,本文提出了一种... 详细信息

多基线相位解缠技术通过扩展InSAR干涉相位的模糊度区间,突破了单基线解缠的相位连续性限制。然而,相位噪声始终困扰着多基线解缠,聚类分析算法能够在一定程度上抑制噪声,但聚类簇边界的相位连续性难以保障。针对该问题,本文提出了一种离散优化多基线InSAR抗噪相位解缠方法,该方法将经典的多基线解缠模型转化为离散优化问题,构建了多基线解缠解析框架。本文方法以双向遍历的形式求解相位模糊度,针对相位噪声引起的模糊度个数突变问题,采用分块聚类的策略予以校正,提高了算法的抗噪稳健性,解决了聚类簇边界跳变问题。本文基于模拟数据集及实测数据集验证了本文方法的有效性。结果表明,本文方法相对于传统聚类方法,均方根误差减少了约20%。

关键词：多基线 InSAR相位解缠离散优化聚类分析相位连续性假设

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矿用带式输送机控制系统设计优化

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机械管理开发 2024年第3期39卷 219-221页

作者：吴章锋山西阳城阳泰集团屯城煤业有限公司山西阳城048103

以某煤矿矿用带式输送机控制系统为研究对象,介绍了一种矿用带式输送机控制系统设计优化方案。该方案在原控制系统基础上,增加了现场监控元件和PID控制器。通过利用现场监控元件采集到的数据进行分析,自动判断带式输送机的运行状态,生... 详细信息

以某煤矿矿用带式输送机控制系统为研究对象,介绍了一种矿用带式输送机控制系统设计优化方案。该方案在原控制系统基础上,增加了现场监控元件和PID控制器。通过利用现场监控元件采集到的数据进行分析,自动判断带式输送机的运行状态,生成并发送相应的控制指令,以此调节带式输送机的运行状态,提升其运行效果。该优化方案为煤矿生产工作的开展打下了良好基础,并确认其具有一定的应用价值。

关键词：矿用带式输送机控制系统 PID控制器

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Instability analysis and drag coefficient prediction on a swept RAE2822 wing with constant lift coefficient

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Chinese Journal of Aeronautics 2017年第3期30卷 964-975页

作者： Zhenrong JING zhangfeng HUANG Department of Mechanics Tianjin University State Key Laboratory of Aerodynamics China Aerodynamics Research and Development Center

Swept wing is widely used in civil aircraft,whose airfoil is chosen,designed and optimized to increase the cruise speed and decrease the drag *** parameters of swept wing,such as sweep angle and angle of attack,are determined according to the cruise lift coefficient requirement,and the drag coefficient is expected to be predicted accurately,which involves the instability characteristics and transition position of the *** pressure coefficient of the RAE2822 wing with given constant lift coefficient is obtained by solving the three-dimensional Navier-Stokes equation numerically,and then the mean flow is calculated by solving the boundary layer（BL） equation with spectral *** cross-flow instability characteristic of boundary layer of swept wing in the windward and leeward is analyzed by linear stability theory（LST）,and the transition position is predicted by *** drag coefficient is numerically predicted by introducing a laminar/turbulent indicator.A simple approach to calculate the lift coefficient of swept wing is *** is found that there is a quantitative relationship between the angle of attack and sweep angle when the lift coefficient keeps constant;when the angle of attack is small,the flow on the leeward of the wing is *** the angle of attack is larger than 3°,the flow becomes unstable quickly;with the increase of sweep angle or angle of attack the disturbance on the windward becomes more unstable,leading to the moving forward of the transition position to the leading edge of the wing;the drag coefficient has two significant jumping growth due to the successive occurrence of transition in the windward and the leeward;the optimal range of sweep angle for civil aircraft is suggested.

关键词： Constant lift coefficient Cross-flow instability Drag coefficient Linear stability theory Swept RAE2822 wing

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Adopting an ecological view of metropolitan landscape: the case of “three circles" system for ecological construction and restoration in Beijing area

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Journal of Environmental Sciences 2004年第4期16卷 610-615页

作者： zhangfeng ZHANGXin-shi LaboratoryofQuantitativeVegetationEcology InstituteofBotanyChineseAcademyofSciencesBeijing100093China

Ecological construction and restoration for sustainable development are now a driving paradigm. It is increasingly recognized that ecological principles, especially landscape ecology theory, are not only necessary but also essential to maintain the long-term sustainability worldwide. Key landscape ecology principles—element, structure and process, dynamics, heterogeneity, hierarchies, connectivity, place and time were reviewed, and use Beijing area as a case study to illustrate how these principles might be applied to ecological construction and restoration, to eventually achieve sustainability. An example to more effectively incorporate the ecological principles in sustainable planning in China was presented.

关键词： landscape ecology ecological principles ecological benefits Beijing

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Pt/Co_(x)Al催化剂上乙酰丙酸甲酯加氢与甲醇水液相重整反应耦合制备γ-戊内酯

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燃料化学学报（中英文） 2024年第9期52卷 1266-1279页

作者：吕泽祥朱善辉董梅秦张峰樊卫斌王建国中国科学院山西煤炭化学研究所煤炭高效低碳利用全国重点实验室山西太原030001 中国科学院大学北京100049

生物质衍生物乙酰丙酸甲酯(ML)加氢制备高值化学品γ-戊内酯(GVL)通常需要在高压氢气中进行,存在成本高和危险性大等问题。本研究采用Pt/Co_(x)Al催化剂,将ML加氢反应与甲醇水液相重整(APRM)相耦合制备GVL,甲醇重整所获得的氢气原位用... 详细信息

生物质衍生物乙酰丙酸甲酯(ML)加氢制备高值化学品γ-戊内酯(GVL)通常需要在高压氢气中进行,存在成本高和危险性大等问题。本研究采用Pt/Co_(x)Al催化剂,将ML加氢反应与甲醇水液相重整(APRM)相耦合制备GVL,甲醇重整所获得的氢气原位用于ML的加氢反应,避免了外部氢源的使用,并考察了催化剂组成、反应溶液浓度和反应温度等条件对催化反应性能的影响。结果表明,Pt/Co_(x)Al催化剂在该耦合反应体系中具有优异的催化性能,GVL收率高达98.2%,六次循环后性能仍保持稳定。多种表征手段证明,Pt^(0)是ARPM和ML加氢反应的活性中心,Bronsted酸位点则促进ML水解和中间体的内酯化反应,两者之间的协同作用推动了GVL的生成。Pt与CoxAl载体之间存在强相互作用,Co含量适宜时,Pt/Co_(x)Al催化剂具有较高的Pt分散度和丰富的Br?nsted酸位点,因而表现出优异的催化性能。这些结果对探索新型高效的生物质衍生物制备燃料和化学品反应过程具有重要的参考价值。

关键词：甲醇液相重整乙酰丙酸甲酯 γ-戊内酯 Pt 加氢反应

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Conservation relation of generalized growth rate in boundary layers

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Applied Mathematics and Mechanics(English Edition) 2018年第12期39卷 1755-1768页

作者： Runjie SONG Lei ZHAO zhangfeng HUANG Department of Mechanics Tianjin University Hypervelocity Aerodynamics Institute China Aerodynamics Research and Development Center

The elementary task is to calculate the growth rates of disturbances when the e;method in transition prediction is performed. However, there is no unified knowledge to determine the growth rates of disturbances in three-dimensional（3 D） flows. In this paper, we study the relation among the wave parameters of the disturbance in boundary layers in which the imaginary parts of wave parameters are far smaller than the real *** generalized growth rate（GGR） in the direction of group velocity is introduced, and the conservation relation of GGR is strictly deduced in theory. This conservation relation manifests that the GGR only depends on the real parts of wave parameters instead of the imaginary parts. Numerical validations for GGR conservation are also provided in the cases of first/second modes and crossflow modes. The application of GGR to the eN method in 3 D flows is discussed, and the puzzle of determining growth rates in 3 D flows is clarified. A convenient method is also proposed to calculate growth rates of disturbances in 3 D flows. Good agreement between this convenient method and existing methods is found except the condition that the angle between the group velocity direction and the x-direction is close to 90?which can be easily avoided in practical application.

关键词： generalized growth rate(GGR) boundary layer stability e^N method

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水热预处理Zn/HZSM-5催化剂对其催化乙烯芳构化反应性能的影响

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燃料化学学报（中英文） 2024年第8期52卷 1079-1087页

作者：邵嘉蓓李柏超董梅樊卫斌秦张峰王建国中国科学院山西煤炭化学研究所、煤炭高效低碳利用国家重点实验室山西太原030001 中国科学院大学北京100049

针对用于低碳烯烃芳构化的Zn/HZSM-5催化剂存在易于结焦失活的问题,采用高温水热的方法对催化剂进行预处理,通过XRD、N2物理吸附-脱附、NH3-TPD、Py-FTIR、XPS和TG等技术对样品进行表征,并以乙烯芳构化为探针反应考察了高温水热预处理... 详细信息

针对用于低碳烯烃芳构化的Zn/HZSM-5催化剂存在易于结焦失活的问题,采用高温水热的方法对催化剂进行预处理,通过XRD、N2物理吸附-脱附、NH3-TPD、Py-FTIR、XPS和TG等技术对样品进行表征,并以乙烯芳构化为探针反应考察了高温水热预处理对催化剂反应性能和稳定性的影响。结果表明,Zn/HZSM-5催化剂经高温水热预处理48 h后表现出优异的催化性能,虽然乙烯转化率略微降低,但是催化剂寿命显著延长,由72 h延长至216 h,同时芳烃选择性保持在60%以上;水热处理促进了ZnO物种与B酸中心的相互作用及ZnOH+物种的生成,在抑制氢转移反应的同时显著促进了催化剂的脱氢性能,提高了氢气选择性;此外,水热处理后催化剂容碳量明显增加、积炭速率降低,表现出优异的抗结焦积炭特性。

关键词： Zn/HZSM-5 水热预处理乙烯芳构化 Zn物种

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