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Optimizing Raman quantum memory with dynamic phase

Science China(Information Sciences) 2023年第8期66卷 61-71页

作者： Sheng MING Jinxian GUO Yuan WU Guzhi BAO Shuhe WU Minwei SHI Liqing CHEN weiping ZHANG School of Physics and Astronomy and Tsung-Dao Lee Institute Shanghai Jiao Tong University Shanghai Research Center for Quantum Sciences state Key Laboratory of Precision Spectroscopy Quantum Institute of Atom and Light Department of PhysicsEast China Normal University Collaborative Innovation Center of Extreme Optics Shanxi University Shanghai Branch Hefei National Laboratory

Optical quantum memory is a key component of emerging quantum technologies and applications. One of the most promising protocols, far-off-resonant Raman memory, is still beset by its *** now, the only effective method for enhancing its efficiency in experiments has been the intensity modulation method on the control field, while the experimental demonstrations still fail to meet the theoretical expectation. In this study, we experimentally demonstrate how to optimize the Raman quantum memory process using a new method called phase modulation; 52.7% total memory efficiency is realized by applying a phase modulation on the control field with a near-square intensity waveform of the control field, thereby resulting in an increase in efficiency of 13.3% compared to the best case of no phase modulation. Additionally, a hybrid method, combining the phase and intensity modulations, is demonstrated with 87.3% memory efficiency. Such high-efficiency results in 99.0% unconditional fidelity even at near single photon level. The unconditional fidelity is always higher than that of the intensity method as the input photon number of the signal increases and can still beat the nonclone limit, even at 128.1 photons/pulse. Our phase modulation method has great potential applications in quantum information processing due to the advantages of low experimental requirements but an additional degree of freedom and high performance, especially for the high speed and high photon number state manipulation.

关键词： quantum information quantum optics quantum communication quantum memory Raman scattering

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FTransCNN:基于模糊融合的Transformer-CNN不确定性医学图像分割模型

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小型微型计算机系统 2024年第6期45卷 1426-1435页

作者：王海鹏丁卫平黄嘉爽鞠恒荣曹金鑫刘传升南通大学信息科学技术学院江苏南通226019

准确的医学图像分割对于疾病的诊断和治疗至关重要,将多个模型提取的分割特征进行联合使用时存在异质性、不确定性等问题,针对这一问题,本文提出了一种基于模糊融合策略的Transformer-CNN模型(FTransCNN).首先以CNN和Transformer作为骨... 详细信息

准确的医学图像分割对于疾病的诊断和治疗至关重要,将多个模型提取的分割特征进行联合使用时存在异质性、不确定性等问题,针对这一问题,本文提出了一种基于模糊融合策略的Transformer-CNN模型(FTransCNN).首先以CNN和Transformer作为骨干网络,并行提取图片的特征信息;其次使用通道注意力促进Transformer全局关键信息,使用空间注意力增强CNN特征局部细节;接着应用Hadamard乘积对来自两个分支特征之间的细粒度交互进行建模,用Choquet模糊积分抑制融合特征的异质性以及融合特征的不确定性;然后使用Fuzzy Attention Fusion Module(FAFM)分级上采样,有效地捕获低级空间特征和高级语义上下文;最后反卷积得到最终的分割结果.在Chest X-ray数据集、Kvasir-SEG数据集和DRIVE数据集上的实验效果表明,FTransCNN与其它深度分割模型相比,在分割任务上有更好的效果.

关键词： Choquet模糊积分模糊融合医学图像分割 Transformer CNN

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The effects of water depth on the growth and reproduction of Potamogeton crispus in an in situ experiment

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Journal of Plant Ecology 2017年第3期10卷 546-558页

作者： Nannan Zhou weiping Hu Jiancai Deng Jinge Zhu Weiwei Xu Xin Liu state Key Laboratory of Lake Science and Environment Nanjing Institute of Geography and LimnologyChinese Academy of Sciences73 East Beijing RoadNanjing 210008JiangsuChina College of Environmental Science and Engineering Anhui Normal University189 South Jiuhua RoadWuhu 241000AnhuiChina university of the Chinese Academy of Sciences 19 Yuquan RoadBeijing 100049China

Aims Water level is one of the most important determinants of the distri-bution and composition of submersed aquatic vegetation in shal-low *** changes in nutrient loading,large-scale declines in submerged macrophytes in shallow lakes are largely attributed to strong external or internal forces,including changes in water *** a winter-active submerged macrophyte,Potamogeton crispus has important functions in aquatic *** objec-tives of our study were to reveal the effects of water depths on the germination,growth,reproduction and morphological changes of *** under natural environmental conditions;identify the optimum water depth range for colonization of ***;and pre-dict the succession course for *** in Lake *** A long-term in situ experiment was performed to study the effects of water depth on the growth and morphology of *** across the entire life *** were grown in the improved cross type of rhizotrons for 30 weeks at three different water depths(60,120 and 200 cm)in Dongtaihu Bay of Lake *** measured the plant height,root length,the length and width of leaves and counted the numbers of leaves,ramets,turion spikes and roots of each plant on each observation day during the *** Findings Water depths ranging from 60 to 120 cm were favourable for above-ground vegetation growth,root tissue growth and the reproductive ability of *** water depth of 200 cm or beyond,the distri-bution of *** will be limited in the following year because of the lack of turion formation and the severe inhibition of ramet *** relationship between above-ground biomass and growth time at three different water depths fits a logistic growth curve well(P<0.001).The rapid growth and distribution with high density of *** at water depth near 60 cm during the reproductive stage is not favourable for growth of other submerged *** a continuous water depth of~60-120 cm is the op

关键词： influence strength morphology responses rhizotron shallow lakes submerged plant

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Variability of the Kuroshio extension system in 1992-2013 from satellite altimetry data

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Geodesy and Geodynamics 2017年第2期8卷 103-110页

作者： weiping Jiang Lifeng Peng Taoyong Jin Shengjun Zhang Research Center of GNSS Wuhan University Wuhan 430079 China School of Geodesy and Geomatics Wuhan University Wuhan 430079 China Key Laboratory of Geospace Environment and Geodesy Ministry of Education Wuhan 430079China

The Kuroshio Extension （KE） plays an important role in climate and environmental change in the North Pacific. In this paper, more than 20 years of merged absolute dynamic topography and merged sea level anomaly products from satellite altimetry are used to analyze the stability of the KE system. By analyzing the annually averaged sea surface topography, the variations of inter-annual path and annually averaged eddy kinetic energy at the KE region, the KE＇s two dynamic states are given as： the relatively stable state during 1993 1995, 2002-2005, and 2010-2012, and the unstable dynamic state among 1996-2001 and 2006-2009. During the stable state, the KE spindle had a shorter path length and smaller time-varying amplitude, as well as a trend to move northward. While during the unstable state, the KE spindle had a longer path length and an integral southward transport trend, and was observed to oscillate significantly over time. The analysis on the KE＇s upstream and downstream region gives the same variations, indi- cating that they are significantly affected by the El Nino events. The power spectrum of the mean latitudinal position variation of the KE＇s upstream and downstream shows significant quasi-decadal oscillation characteristics and strong annual signals. Furthermore, the correlation of the strength vari- ation between the southern RG and the KE＇s upstream is calculated to be 0.50 after low-pass filtering, and that of the mean latitudinal position variation between the southern RG and the KE＇s upstream/ downstream are 0.75/0.69 after low-pass filtering, respectively. The strong correlations demonstrated that the southern RG and the KE are closely linked.

关键词： Kuroshio extension Satellite altimetry Eddy kinetic energy Southern recirculation gyre Quasi-decadal oscillation

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Amorphous NiO_(n)coupled with trace PtO_(x)toward superior electrocatalytic overall water splitting in alkaline seawater media

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Nano Research 2023年第5期16卷 6517-6530页

作者： Wenli Yu Hongru Liu Ying Zhao Yunlei Fu weiping Xiao Bin Dong Zexing Wu Yongming Chai Lei Wang state Key Laboratory of Heavy Oil Processing College of ScienceChina University of Petroleum(East China)Qingdao 266580China Key Laboratory of Eco-chemical Engineering Ministry of EducationInternational Science and Technology Cooperation Base of Eco-chemical Engineering and Green ManufacturingCollege of Chemistry and Molecular EngineeringQingdao University of Science and TechnologyQingdao 266042China College of Science Nanjing Forestry UniversityNanjing 210037China

Developing corrosion resistance bifunctional electrocatalysts with high activity and stability toward both hydrogen evolution reaction(HER)and oxygen evolution reaction(OER),especially electrolysis in seawater,is of prime significance but still pressingly ***,in-situ introduced PtO_(x)on the derivative amorphous NiO_(n)is prepared via heat treatment of Ni ZIFL nanosheets on nickel foam under low temperature(PtO_(x)-NiO_(n)/NF).The synthesized PtO_(x)-NiO_(n)/NF possesses suprahydrophilic and aerophilic surface,then in favor of intimate contact between the electrode and electrolyte and release of the generated gas bubbles during the *** a result,the in-situ PtO_(x)-NiO_(n)/NF electrode presents outstanding bifunctional activity,which only requires extremely low overpotentials of 32 and 240 mV to reach a current density of 10 mA·cm^(-2)for HER and OER,respectively,which exceeds most of the electrocatalysts previously developed and even suppresses commercial Pt/C and RuO_(2)*** for two-electrode cell organized by PtO_(x)-NiO_(n)/NF,the voltages down to 1.57 and 1.58 V are necessary to drive 10 mA·cm^(-2)with remarkable durability in 1 M KOH and alkaline seawater,respectively,along with remarkable ***,a low cell voltage of 1.88 V is needed to achieve 1,000 mA·cm^(-2)toward water-splitting under industrial *** study provides a new idea for designing in-situ amorphous metal oxide bifunctional electrocatalyst with strong Pt–support interaction for overall water splitting.

关键词： hydrogen/oxygen evolution reaction alkaline seawater splitting amorphous structure ultralow Pt electrocatalyst

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计及风电的发电商报价多智能体模型

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计算机科学 2024年第S1期51卷 1183-1190页

作者：黄飞虎李沛东彭舰董石磊赵红磊宋卫平李强四川中电启明星信息技术有限公司成都610000 四川大学计算机学院成都610065 国网信息通信产业集团有限公司北京102211

新型电力系统背景下,新能源发电商的报价问题一直是电力现货市场中的研究热点。相比传统能源,风电出力受外界不确定性因素的影响较大,给风力发电商求解最优报价带来了挑战。为此,基于多智能体强化学习算法WoLF-PHC构建了计及风电的发电... 详细信息

新型电力系统背景下,新能源发电商的报价问题一直是电力现货市场中的研究热点。相比传统能源,风电出力受外界不确定性因素的影响较大,给风力发电商求解最优报价带来了挑战。为此,基于多智能体强化学习算法WoLF-PHC构建了计及风电的发电商报价策略模型。模型中,考虑了风电、火电和水电3种能源参与的现货市场,每一个发电商抽象为一个智能体,且基于随机约束规划算法建模风电智能体的收益函数;对于智能体的报价策略模型,将D3QN与WoLF-PHC算法结合,使模型能够满足报价时智能体状态空间复杂的情况;此外,对于交互环境的建模,提出利用DDPM扩散模型生成风电出力数据,优化风电出清场景的仿真。最后,基于3节点的电力仿真系统开展模拟实验,实验结果表明,提出的风电收益函数建模、WoLF-PHC改进、风电出力生成等技术是可行的,能有效解决风电参与竞价的现货市场报价问题,并且能够在较少的迭代次数后学习到较优的策略。

关键词： WoLF-PHC 多智能体强化学习电力现货市场竞价策略扩散模型

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Functionalised B-Cu@F-Ag@Au trimetallic nanomaterials with long term stability for rapid and highly sensitive in situ SERS detection of furfural in transformer oil

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High Voltage 2023年第2期8卷 293-304页

作者： Yu Lei Changding Wang weiping Kong Mingliang Wang Xinyuan Zhang Abdolmaleki Nima Caisheng Wang Weigen Chen Fu Wan School of Electrical Engineering Chongqing UniversityChongqingChina state Key Laboratory of Power Transmission Equipment and System Security and New Technology Chongqing UniversityChongqingChina Electrical and Computer Engineering Wayne State UniversityWayneNebraskaUSA

The surface-enhanced Raman scattering(SERS)substrates enable a highly sensitive detection of furfural in the transformer ***,detection substrates with long-term stability are still extremely *** this work,we anchored the thiol-containing coupling agents 2,5-dimercapto-1,3,4-thiadiazole(DMTD)and 1,4-benzenedithiol(BDT)on the surface of bubble copper(B-Cu)and flower-like silver nanoparticles(FAg),*** three-dimensional SERS detection substrates with long-term stability by using a combination of chemical reduction and self-assembly methods were *** substrate has a minimum detection limit of 10^(−9) M for rhodamine B in oil with an enhancement factor of up to 2.23×10^(7).Importantly,the three-crystal BCu@F-Ag_(1)@Au_(5) substrate was used for the detection of furfural in the transformer oil with a detection limit of 2 mg/L and a relative standard deviation value of 2.46%.After 60 days of a simulated operation,the detection signal of furfural in the transformer oil samples at 75℃ and still reached the initial value of 77.53%,indicating that the substrate has a good long-term *** triple frame structured SERS detection platform shows great potential in tracking furfural in the aging transformer oil mixing systems.

关键词： stability. stability SERS

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Catalytic transformation of cellulose and its derived carbohydrates into chemicals involving C–C bond cleavage

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Journal of Energy Chemistry 2015年第5期24卷 595-607页

作者： weiping Deng Qinghong Zhang Ye Wang state Key Laboratory of Physical Chemistry of Solid Surfaces Collaborative Innovation Center of Chemistry for Energy Materials National Engineering Laboratory for Green Chemical Productions of Alcohols Ethers and Esters College of Chemistry and Chemical Engineering Xiamen University

The catalytic transformation of cellulose, the major component of abundant and renewable lignocellulosic biomass, into building-block chemicals is a key to establishing sustainable chemical processes. Cellulose is a polymer of glucose and a lot research effort has been devoted to the conversion of cellulose to six-carbon platform compounds such as glucose and glucose derivatives through C-O bond activation. There also ex- ist considerable studies on the catalytic cleavage of C-C bonds in biomass for the production of high-value chemicals, in particular polyols and organic acids such as ethylene glycol and lactic acid. This review article highlights recent advances in the development of new catalytic systems and new strategies for the selective cleavage of C-C bonds in cellulose and its derived carbohydrates under inert, reductive and oxidative atmospheres to produce Q -Cs polyols and organic acids. The key factors that influence the catalytic performance will be clarified to provide insights for the design of more efficient catalysts for the transformation of cellulose with precise cleavage of C-C bonds to high-value chemicals. The reaction mechanisms will also be discussed to understand deeply how the selective cleavage of C-C bonds can be achieved in biomass.

关键词： Biomass Cellulose C-C bond activation Polyols Organic acids

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The modification toward excited-state dynamics and catalytic activity by isomeric Au_(44)clusters

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Nano Research 2023年第8期16卷 11383-11388页

作者： Tongxin Song Jie Kong Shisi Tang Xiao Cai Xu Liu Meng Zhou Wen Wu Xu weiping Ding Yan Zhu School of Chemistry and Chemical Engineering Nanjing UniversityNanjing 210093China Hefei National Research Center for Physical Sciences at the Microscale University of Science and Technology of ChinaHefei 230026China School of Physical Science and Technology Ningbo UniversityNingbo 315211China

The structure determination of metal nanoclusters protected by ligands is critical in understanding their physical and chemical properties,yet it remains elusive how the metal core and ligand of metal clusters cooperatively contribute to the observed ***,with the successful synthesis of Au_(44)TBPA_(22)Cl_(2)cluster(TBPA=4-tert-butylphenylacetylene),the structural isomer of previously reported Au_(44)L_(28)clusters(L denoted as ligand)is filled,thereby providing an opportunity to explore the property evolution rules imparted by different metal core structures or different surface ***-resolved transient absorption spectroscopy reveals that the difference in the core structure between Au_(44)TBPA_(22)Cl_(2)and Au_(44)L_(28)can bring nearly 360 times variation of excited-state lifetime,while only 3–24 times differences in excited-state lifetimes of the three Au_(44)L_(28)nanoclusters with identical metal core but different ligands are observed,which is due to much stronger impact of the metal core than the surface ligands in the electronic energy bands of the *** addition,the Au_(44)clusters protected by alkyne ligands are shown to be highly effective toward the electrochemical oxidation of ethanol,compared to the Au_(44)clusters capped by thiolates,which is ascribed to smaller charge transfer impedance of the former *** anticipate that the study will enhance the process in controlling the nanomaterial properties by precisely tailoring metal core or surface patterns.

关键词： cluster metal core surface ligand excited-state dynamics catalysis

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海洋大气环境下锈蚀钢构件疲劳性能研究进展

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工业建筑 2024年第1期54卷 11-19页

作者：余倩倩常安顾祥林张伟平姜超土木工程防灾减灾全国重点实验室上海200092 同济大学建筑工程系上海200092 工程结构性能演化与控制教育部重点实验室上海200092

疲劳破坏是引起金属结构破坏的最主要原因之一,若考虑锈蚀,问题更为复杂。国内外学者对锈蚀钢构件疲劳性能进行了系统全面的研究。文章以“锈蚀电化学过程—锈蚀表征方法—锈蚀钢构件疲劳性能”为主线,对相关研究成果进行回顾与分析。... 详细信息

疲劳破坏是引起金属结构破坏的最主要原因之一,若考虑锈蚀,问题更为复杂。国内外学者对锈蚀钢构件疲劳性能进行了系统全面的研究。文章以“锈蚀电化学过程—锈蚀表征方法—锈蚀钢构件疲劳性能”为主线,对相关研究成果进行回顾与分析。结果表明:对钢材锈蚀的电化学过程、锈蚀疲劳破坏一般规律、锈蚀特征的单一表征方法等方面已有了清晰的认识。但是,锈蚀钢结构疲劳性能时变演化规律的精准预测仍然面临重大挑战。未来需要进一步研究钢结构锈坑时空分布规律和形貌特征参数随机模型、自然环境和环境箱人工环境中钢结构锈蚀机理相似性、海洋大气环境下锈蚀钢结构疲劳性能随机演化机理,以及锈蚀钢结构疲劳性能控制与提升。

关键词：海洋大气钢构件锈蚀疲劳

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