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Four-dimensional direct detection receiver enabling Jones-space field recovery with phase and polarization diversity

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Photonics Research 2024年第3期12卷 399-410页

作者： QI WU YIXIAO ZHU XUEYANG LI HEXUN JIANG chen chenG MENGFAN FU YIKUN ZHANG QUNBI ZHUGE ZHAOHUI LI weisheng HU Peng cheng Laboratory Shenzhen 518055China State Key Laboratory of Advanced Communication Systems and Networks Department of Electronic EngineeringShanghai Jiao Tong UniversityShanghai 200240China School of Electronics and Information Technology and Guangdong Provincial Key Laboratory of Optoelectronic Information Processing Chips and Systems Sun Yat-sen UniversityGuangzhou 510006China

Data centers,the engines of the global Internet,rely on powerful high-speed optical interconnects.In optical fiber communication,classic direct detection captures only the intensity of the optical field,while the coherent detection counterpart utilizes both phase and polarization diversities at the expense of requiring a narrow-linewidth and high-stability local oscillator(LO).Herein,we propose and demonstrate a four-dimensional Jones-space optical field recovery(4-D JSFR)scheme without an LO.The polarization-diverse full-field receiver structure captures information encoded in the intensity and phase of both polarizations,which can be subsequently extracted digitally.To our knowledge,our proposed receiver achieves the highest electrical spectral efficiency among existing direct detection systems and potentially provides similar electrical spectral efficiency as standard intradyne coherent detection systems.The fully recovered optical field extends the transmission distance beyond the limitations imposed by fiber chromatic dispersion.Moreover,the LO-free advantage makes 4-D JSFR suitable for photonic integration,offering a spectrally efficient and cost-effective solution for massively parallel data center interconnects.Our results may contribute to the ongoing developments in the theory of optical field recovery and the potential design considerations for future high-speed optical transceivers.

关键词： polarization receiver phase

Digital twin modeling and controlling of optical power evolution enabling autonomous-driving optical networks:a Bayesian approach

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Advanced Photonics 2024年第2期6卷 69-80页

作者： Xiaomin Liu Yihao Zhang Yuli chen Yichen Liu Meng Cai Qizhi Qiu Mengfan Fu Lilin Yi weisheng Hu Qunbi Zhuge Shanghai Jiao Tong University State Key Laboratory of Advanced Optical Communication Systems and NetworksDepartment of Electronic EngineeringShanghaiChina

Optical networks are evolving toward ultrawide bandwidth and autonomous operation.In this scenario,it is crucial to accurately model and control optical power evolutions(OPEs)through optical amplifiers(OAs),as they directly affect the signal-to-noise ratio and fiber nonlinearities.However,a fundamental contradiction arises between the complex physical phenomena in optical transmission and the required precision in network control.Traditional theoretical methods underperform due to ideal assumptions,while data-driven approaches entail exorbitant costs associated with acquiring massive amounts of data to achieve the desired level of accuracy.In this work,we propose a Bayesian inference framework(BIF)to construct the digital twin of OAs and control OPE in a data-efficient manner.Only the informative data are collected to balance the exploration and exploitation of the data space,thus enabling efficient autonomous-driving optical networks(ADONs).Simulations and experiments demonstrate that the BIF can reduce the data size for modeling erbium-doped fiber amplifiers by 80%and Raman amplifiers by 60%.Within 30 iterations,the optimal controlling performance can be achieved to realize target signal/gain profiles in links with different types of OAs.The results show that the BIF paves the way to accurately model and control OPE for future ADONs.

关键词： optical fiber communications digital twin Bayesian inference optical amplifiers autonomous-driving optical networks

Output-feedback adaptive stochastic nonlinear stabilization using neural networks

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Journal of Systems Engineering and Electronics 2010年第1期21卷 81-87页

作者： weisheng chen Department of Applied Mathematics Xidian University Xi'an 710071 E R. China

For the first time, an adaptive backstepping neural network control approach is extended to a class of stochastic non- linear output-feedback systems. Different from the existing results, the nonlinear terms are assumed to be completely unknown and only a neural network is employed to compensate for all unknown nonlinear functions so that the controller design is more simplified. Based on stochastic LaSalle theorem, the resulted closed-loop system is proved to be globally asymptotically stable in probability. The simulation results further verify the effectiveness of the control scheme.

关键词： neural network output-feedback nonlinear stochastic systems backstepping.

ADAPTIVE TRACKING CONTROL FOR ACTUATOR FAILURE COMPENSATION BASED ON MT-FILTERS

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Journal of Systems Science & Complexity 2010年第4期23卷 759-768页

作者： Zhengqiang ZHANG weisheng chen School of Automation Nanjing University of Science and Technology Nanjing 210094 China Department of Electrical Engineering and Automation Qufu Normal University Rizhao 276826 China. Department of Applied Mathematics Xidian University Xian 710071 China

This paper considers the problem of actuator failure compensation for a class of nonlinearsystems in the form of output-feedback.MT-filters are exploited to estimate the unmeasured states.The backsteppping technique is used to construct the controller recursively.The proposed compensationscheme can grantee the boundedness of all the closed-loop signals and asymptotic output tracking.Thetheoretical results are illustrated by a simulation example.

关键词：自适应跟踪控制补偿器过滤器执行器失效非线性系统执行器故障输出反馈输出跟踪

Oscillation of Dzyaloshinskii–Moriya interaction driven by weak electric fields

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Chinese Physics B 2024年第2期33卷 487-491页

作者：陈润泽曹安妮王馨苒柳洋杨洪新赵巍胜 Fert Beijing Institute MIIT Key Laboratory of SpintronicsSchool of Integrated Circuit Science and EngineeringBeihang UniversityBeijing 100191China Hefei Innovation Research Institute Beihang UniversityHefei 230013China Beihang-Goertek Joint Microelectronics Institute Qingdao Research InstituteBeihang UniversityQingdao 266000China National Laboratory of Solid State Microstructures School of PhysicsCollaborative Innovation Center of Advanced MicrostructuresNanjing UniversityNanjing 210093China Beijing Microelectronics Technology Institute Beijing 100076China

Dzyaloshinskii–Moriya interaction(DMI) is under extensive investigation considering its crucial status in chiral magnetic orders, such as Néel-type domain wall(DW) and skyrmions. It has been reported that the interfacial DMI originating from Rashba spin–orbit coupling(SOC) can be linearly tuned with strong external electric fields. In this work, we experimentally demonstrate that the strength of DMI exhibits rapid fluctuations, ranging from 10% to 30% of its original value, as a function of applied electric fields in Pt/Co/MgO heterostructures within the small field regime(< 10-2V/nm). Brillouin light scattering(BLS) experiments have been performed to measure DMI, and first-principles calculations show agreement with this observation, which can be explained by the variation in orbital hybridization at the Co/MgO interface in response to the weak electric fields. Our results on voltage control of DMI(VCDMI) suggest that research related to the voltage control of magnetic anisotropy for spin–orbit torque or the motion control of skyrmions might also have to consider the role of the external electric field on DMI as small voltages are generally used for the magnetoresistance detection.

关键词： Dzyaloshinskii-Moriya interaction weak electric field control effect Rashba spin-orbit coupling interfacial orbital hybridization

三种流动控制方法对H型垂直轴风力机性能影响的对比分析

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太阳能学报 2024年第3期45卷 105-115页

作者：刘永飞陈微圣孙晓晶上海理工大学能源与动力工程学院上海200093 上海市动力工程多相流动与传热重点实验室上海200093

采用数值模拟的方法,分别以基于NACA0021和NACA0018翼型表面带吸气缝叶片的升力型垂直轴风力机为二维、三维研究对象,研究叶片表面施加吸气对提高升力型(H型)垂直轴风力机叶片做功性能的效果。通过开展二维模拟研究,探究多吸气缝在叶片... 详细信息

采用数值模拟的方法,分别以基于NACA0021和NACA0018翼型表面带吸气缝叶片的升力型垂直轴风力机为二维、三维研究对象,研究叶片表面施加吸气对提高升力型(H型)垂直轴风力机叶片做功性能的效果。通过开展二维模拟研究,探究多吸气缝在叶片吸力面上的位置对垂直轴风力机气动性能的影响,并对比研究吸气和吹气这两种常用的主动流动控制方法提升垂直轴风力机风能利用净效率的区别。在此基础上,对叶片表面采用吸气控制的垂直轴风力机进行三维数值模拟分析,并将其获能特性与采用波浪前缘叶片即被动流动控制后的垂直轴风力机的性能进行了比较。结果表明,当多吸气缝位置位于距离叶片前缘10%~15%弦长区域范围内时,能最好地抑制垂直轴风力机叶片表面的流动分离,改善叶片的气动性能。与吹气控制方法相比,叶片表面采用吸气控制后的风力机的风能利用净效率在全叶尖速比下的增幅更加明显;而与波浪前缘控制方法相比,采用吸气控制后风力机风能利用净效率在低尖速比下提升效果更为显著,最大提升幅度可达到140%。该文研究结果表明吸气方式可使垂直轴风力机的效率在较大的运行工况内都有明显提高,与吹气和波浪前缘的方法相比在提升风力机气动性能效果方面更为显著,因此也更具工程应用的潜力和优势。

关键词：数值模拟垂直轴风力机流动控制吸气气动性能

衡邵干旱走廊耕地种植结构水分供需评估及其优化

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资源科学 2024年第5期46卷 1032-1044页

作者：周浩胡凌陈藜藜夏卫生湖南师范大学地理科学学院长沙410081 中南林业科技大学商学院长沙410004

[目的]从种植结构视角,探究耕地利用下水分供需态势并实现其多目标优化调整,为“以水定地”及耕地资源可持续利用提供理论参考。[方法]以衡邵干旱走廊为研究区,在气象站点、土地利用、作物种植以及农业社会经济等多源数据支持下,基于耕... 详细信息

[目的]从种植结构视角,探究耕地利用下水分供需态势并实现其多目标优化调整,为“以水定地”及耕地资源可持续利用提供理论参考。[方法]以衡邵干旱走廊为研究区,在气象站点、土地利用、作物种植以及农业社会经济等多源数据支持下,基于耕地种植结构视角,微观精准揭示1980-2020年不同气候类型年份耕地种植结构下的水分供需态势及灌溉需求,并构建不同灌溉需水情景下的耕地种植结构多目标优化模型,同时设定“水-土-粮”多重约束,确定耕地种植结构优化策略。[结果](1)双季稻和油菜全生育期的水分自然供给优于单季稻及玉米,且水稻耗水量较高,尤其干旱年双季稻平均需水量高达608.29 mm;(2)水稻和玉米全生育期的有效降水空间与需水格局相异,导致研究区东南部的作物干旱情势加剧,而油菜整体水分供需态势良好;(3)双季稻和单季稻的水分亏缺程度较高,年均净灌溉需水量分别达到303.68 mm、257.00 mm,旱生作物的水分供需矛盾较小,种植管理过程无需过度依赖农业灌溉;(4)经种植结构优化,在设定节水目标并实现优化调控后能够显著提高耕地生产综合效益,尤其是权重情景3的湿润年水资源约束下预期粮食产量可提升5.12%;权重情景1和2的湿润年水资源约束下作物种植减税纯收益可提升22.34%。[结论]衡邵干旱走廊在干旱年的种植结构应基本保持稳定,平水年可适当增加单季稻面积、调减旱作物种植比例,湿润年可大幅增加粮食作物播种面积并调减油菜面积,以提升耕地种植的综合效益。

关键词：耕地种植结构水分供需灌溉需求优化利用衡邵干旱走廊

Exponentially weighted proportional fair scheduling algorithm for the OFDMA system

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Science China(Information Sciences) 2019年第4期62卷 177-186页

作者： Siyu LIANG weisheng chen Yake LI Xinpeng FANG School of Aerospace Science and Technology Xidian University

This study aims to propose an exponentially weighted proportional fair(EWPF) scheduling algorithm for orthogonal frequency division multiple access(OFDMA) system for long-term evolution downlink transmission. The proposed algorithm improves the system performance in the user-perceived throughput(UPT) by adding exponential weights to different types of services. The UPT employed to measure the system capability is novel and customer oriented; it reflects the experiences of users in an efficient manner and determines whether the user’s scheduling is reasonable. The EWPF algorithm is compared with two other schedulers, and our simulation results showed that the EWPF can increase the overall UPT and can maintain the fairness for prioritizing the transmission of some types of traffic.

关键词： exponentially weighted proportional fair user perceived throughput downlink scheduling algorithm scheduled IP throughput

N-acetylaspartylglutamate Inhibits Heroin Self-Administration and Heroin-Seeking Behaviors Induced by Cue or Priming in Rats

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Neuroscience Bulletin 2017年第4期33卷 396-404页

作者： Huaqiang Zhu Miaojun Lai weisheng chen Disen Mei Fuqiang Zhang Huifeng Liu Wenhua Zhou Laboratory of Behavioral Neuroscience Ningbo AddictionResearch and Treatment Center School of MedicineNingbo UniversityNingbo 315010China

Activation of presynaptic group II metabotropic glutamate receptors（mGluR2/3） inhibits drug reward and drug-seeking behavior, but the role of N-acetylaspartylglutamate（NAAG）, an agonist of endogenous mGluR2/3,in heroin reward and heroin-seeking behavior remained unclear. Here, we aimed to explore the effects of exogenous NAAG on heroin self-administration and heroinseeking behavior. First, rats were trained to self-administer heroin under a fixed ratio 1（FR1） schedule for 10 days,then received NAAG（50 or 100μg/10 μL in each nostril）in the absence or presence of LY341495（1 mg/kg, i.p.）, an antagonist of mGluR2/3, on day 11 and the effects of NAAG on heroin self-administration under FR1 were recorded for 3 consecutive days. Motivation was assessed in heroin self-administration under a progressive ratio schedule on day 11 in another 5 groups with the same doses of NAAG. Additional rats were withdrawn for 14 days after 14 days of heroin self-administration, then received the same pharmacological pretreatment and were tested for heroin-seeking behaviors induced by heroin priming or cues. The results showed that intranasal administration of NAAG significantly decreased intravenous heroin selfadministration on day 12, but not on day 11. Pretreatment with LY341495 prior to testing on day 12 prevented the inhibitory effect of NAAG on heroin reinforcement. The break-point for reward motivation was significantly reduced by NAAG. Moreover, NAAG also significantly inhibited the heroin-seeking behaviors induced by heroinpriming or cues and these were restored by pretreatment with LY341495. These results demonstrated that NAAG,via activation of presynaptic mGluR2/3, attenuated the heroin reinforcement, heroin motivational value, and heroin-seeking behavior, suggesting that it may be used as an adjunct treatment for heroin addiction.

关键词： Glutamate Opioid Metabotropic glutamate receptor Reward Addiction