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Impacts of seed power on amplification performance in pulsed double-clad fiber amplifier

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Chinese Optics Letters 2008年第1期6卷 19-21页

作者：张芳沛楼祺洪周军赵宏明杜松涛董景星魏运荣何兵李进延朱健强王之江 Shanghai Institute of Optics and fine Mechanics Chinese Academy of Sciences Fiberhome Telecommunication Tech co.ltd.

A pulsed master-oscillator fiber power amplifier system with near diffraction-limited output by use of China-made large-mode-area fiber and a （2 ＋ 1） × 1 multimode combiner is reported. The effect of the seed power on the amplification performance is found. For the seed power, there exists a range within which the pulsed fiber amplifier can operate safely and reliably at a certain pump power. With the seed average power of 70 mW, the amplification performances of the fiber amplifier are investigated.

关键词： Power amplifiers

Damped Oscillation of Liquid column in Vertical U-Tube for Newtonian and non-Newtonian Liquids

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Journal of Thermal Science 2007年第4期16卷 289-300页

作者： Akira Ogawa Suguru Tokiwa Masatoshi Mutou Kazutaka Mogi Tonau Sugawara Masahide Watanabe Kouhei Satou Toshikazu Kikawada Keitarou Shishido Naoya Matumoto T110-0011.Minowa 2-14-7 Taitou-KuTokyoJapan Asnohorie co.ltd. Japan Yamada manufacturing co.ltd. Japar Polymatech co.ltd. japan Fujikura Rubber com. Japan Furukawa Electric co.ltd. Japan GMA co.ltd. Japan Top corporation co.ltd. Japan Hitachi Unisia co.ltd. Japan Research Student Japan

Damped oscillation of Newtonian liquid in a vertical U-tube is one of the well known phenomena and the solution of this liquid motion for the laminar flow regime in the circular pipe was solved, however, generally speaking, even if the period of the oscillational motion by this solution is nearly coincided with that of the experimental result, the estimation of the damped oscillational process with lapse of time by the solved equation is not in agreement with that of the experimental result. Therefore basing upon the experimental results of the velocity distributions of the oscillational motion in the circular U-tube for the Newtonian and non-Newtonian liquids, the velocity distribution of the Bingham plastic flow is assumed. The solutions of the damped oscillation and also of the vertical falling and rising velocities of the free surface in the vertical U-tube of the diameters D= 10mm, 20mm and 40mm are compared with water and water-glycerine solution for the Newtonian liquids and the acrylic co-polymer solutions for the non-Newtorlian liquid. The comparisons of these solved equations by the new flow model are shown in good agreement with the experimental results. The above stated results are described in detail.

关键词： Damped oscillation Bingham plastic flow Hagen-Poiseuille law Newtonian liquid non-Newtonian liquid.

Experimental Study for Effect of Multi-Site Spark Ignition on Dedicated Hybrid Engine Performance under High Dilution condition

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Journal of Thermal Science 2025年第1期34卷 254-267页

作者： YAN Bowen WATERS Benjamin HAINES Andrew MCGHEE Mike HU Tiegang DENG Wei PU Yongxian MA Tianyu Powertrain Engineering R&D Center Chongqing Changan Automobile Co.Ltd. Changan UK R&D Centre Limited

In this study,a triple spark ignition scheme was first designed on a three-cylinder 1.5-L dedicated hybrid engine（DHE）.On this basis,the effect of different ignition modes on engine combustion and emission characteristics was studied,especially under high dilution *** results tested at 2000 r/min and 0.8 MPa BMEP（brake mean effective pressure） show that with highly increased in-cylinder flow intensity,using only passive prechamber（PPC） has a lower lean limit than that with single central spark plug（CSP）,thereby leading to slightly higher minimum fuel consumption and nitrogen oxides（NOx） *** side spark plugs（SSP）based on PPC can result in improved capability of lean limit extension and engine performance than ***,the improvement level is lower than that with triple spark plugs（TSP）.As the excess air ratio λincreases,the advantage of PPC and PPC with SSP in improving the combustion phasing compared with CSP gradually ***,the increasing tendency of their ignition delay and combustion duration is more *** added SSP based on PPC can effectively shorten the ignition delay of leaner mixture,but the combustion duration can be only slightly *** a result,under extremely lean condition,the advantage of PPC and PPC with SSP in terms of combustion characteristics over CSP becomes much *** contrast,the TSP ignition can achieve much shorter ignition delay and combustion duration simultaneously under this *** to the highest available dilution level,the TSP ignition achieves the lowest raw ***,it can also reduce the raw carbon monoxide（co） and hydrocarbons（HC） emissions compared to CSP due to a more thorough combustion of the end gas *** on the excellent performance of TSP,the highest engine brake thermal efficiency（BTE） was further *** results show that with normal RON 92 fuel,the engine finally achieved 43.69% and 45.02% BTE under stochiometric mode with exhaust

关键词： dedicated hybrid engine high dilution condition NOx emissions passive prechamber thermal efficiency triple spark plug scheme

Staged dendrite suppression for high safe and stable lithium-sulfur batteries

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Journal of Energy chemistry 2025年第1期100卷 674-683页

作者： Jun Jiang Zhenjie Lu Yanwen Ding Shujun Liu Zhijie Qi Tian Tang Yunfan Zhang Zhiyuan Ma Jingwen Sun Liang Xue Wenyao Zhang Pan Xiong Xin Wang Junwu Zhu Yongsheng Fu Key Laboratory for Soft chemistry and Functional Materials of Ministry of Education Nanjing University of Science and Technology Jiangsu Pylon Battery co.ltd

The unavoidable dendrite growth and shuttle effect have long been stranglehold challenges limiting the safety and practicality of lithium-sulfur ***,we propose a dual-action strategy to address the lithium dendrite issue in stages by constructing a multifunctional surface-negatively-charged nanodiamond layer with high ductility and robust puncture resistance on polypropylene （PP） *** uniformly loaded compact negative layer can not only significantly enhance electron transmission efficiency and promote uniform lithium deposition,but also reduce the formation of dendrite during early deposition *** importantly,under the strong puncture stress encountered during the deterioration of lithium dendrite growth under limiting current,the high ductility and robust puncture resistance（145.88 MPa） of as-obtained nanodiamond layer can effectively prevent short circuits caused by unavoidable lithium *** Li||Li symmetrical cells assembled with nanodiamond layer modified PP demonstrated a stable cycle of over 1000 h at 2 mA cm-2with a polarization voltage of only 29.3 ***,the negative charged layer serves as a physical barrier blocking lithium polysulfide ions,effectively mitigating capacity *** improved cells achieved a capacity decay of only 0.042%per cycle after 700 cycles at 3 C,demonstrating effective suppression of dendrite growth and capacity attenuation,showing promising prospect.

关键词： Ductility

Multi-Stage Voltage control Optimization Strategy for Distribution Networks considering Active-Reactive co-Regulation of Electric Vehicles

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Energy Engineering 2025年第1期122卷 221-242页

作者： Shukang Lyu Fei Zeng Huachun Han HuiyuMiao Yi Pan Xiaodong Yuan Electric Power Research Institute State Grid Jiangsu Electric Power Co.Ltd.Nanjing211103China

The high proportion of uncertain distributed power sources and the access to large-scale random electric vehicle(EV)charging resources further aggravate the voltage fluctuation of the distribution network,and the existing research has not deeply explored the EV active-reactive synergistic regulating characteristics,and failed to realize themulti-timescale synergistic control with other regulatingmeans,For this reason,this paper proposes amultilevel linkage coordinated optimization strategy to reduce the voltage deviation of the distribution ***,a capacitor bank reactive power compensation voltage control model and a distributed photovoltaic(PV)activereactive power regulationmodel are ***,an external characteristicmodel of EVactive-reactive power regulation is developed considering the four-quadrant operational characteristics of the *** optimization model of the distribution network is then constructed considering the time-series coupling constraints of multiple types of voltage regulators.A multi-timescale control strategy is proposed by considering the impact of voltage regulators on active-reactive EV energy consumption and PV energy ***,a four-stage voltage control optimization strategy is proposed for various types of voltage regulators with multiple time ***-objective optimization is solved with the improvedDrosophila algorithmto realize the power fluctuation control of the distribution network and themulti-stage voltage control *** results validate that the proposed voltage control optimization strategy achieves the coordinated control of decentralized voltage control resources in the distribution *** effectively reduces the voltage deviation of the distribution network while ensuring the energy demand of EV users and enhancing the stability and economic efficiency of the distribution network.

关键词： Electric vehicle(EV) distribution network multi-stage optimization active-reactive power regulation voltage control

LiDAR-Visual SLAM with Integrated Semantic and Texture Information for Enhanced Ecological Monitoring Vehicle Localization

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computers, Materials & continua 2025年第1期82卷 1401-1416页

作者： Yiqing Lu Liutao Zhao Qiankun Zhao Foreign Environmental cooperation Center Ministry of Ecology and Environment of PRCBeijing100035China Beijing computing Center co. Ltd.Beijing Academy of Science and TechnologyBeijing100083China Beijing Guyu Interactive Artificial Intelligence Application co. Ltd.Beijing100024China

Ecological monitoring vehicles are equipped with a range of sensors and monitoring devices designed to gather data on ecological and environmental *** vehicles are crucial in various fields,including environmental science research,ecological and environmental monitoring projects,disaster response,and emergency management.A key method employed in these vehicles for achieving high-precision positioning is LiDAR(lightlaser detection and ranging)-Visual Simultaneous Localization and Mapping(SLAM).However,maintaining highprecision localization in complex scenarios,such as degraded environments or when dynamic objects are present,remains a significant *** address this issue,we integrate both semantic and texture information from LiDAR and cameras to enhance the robustness and efficiency of data ***,semantic information simplifies the modeling of scene elements,reducing the reliance on dense point clouds,which can be less ***,visual texture information complements LiDAR-Visual localization by providing additional contextual *** incorporating semantic and texture details frompaired images and point clouds,we significantly improve the quality of data association,thereby increasing the success rate of *** approach not only enhances the operational capabilities of ecological monitoring vehicles in complex environments but also contributes to improving the overall efficiency and effectiveness of ecological monitoring and environmental protection efforts.

关键词： LiDAR-Visual simultaneous localization and mapping integrated semantic texture information

Design of a constant-voltage and constant-current controller with dual-loop and adaptive switching frequency control

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Journal of Semiconductors 2015年第5期36卷 104-110页

作者：陈映平李志谦 Sigma Micro co.ltd.

A 5.0-V 2.0-A flyback power supply controller providing constant-voltage （CV） and constant-current （CC） output regulation without the use of an optical coupler is presented. Dual-close-loop control is proposed here due to its better regulation performance of tolerance over process and temperature compared with open loop control used in common. At the same time, the two modes, CC and CV, could switch to each other automatically and smoothly according to the output voltage level not sacrificing the regulation accuracy at the switching phase, which overcomes the drawback of the digital control scheme depending on a hysteresis comparator to change the mode. On-chip compensation using active capacitor multiplier technique is applied to stabilize the voltage loop, eliminate an additional package pin, and save on the die area. The system consumes as little as 100 mW at no-load condition without degrading the transient response performance by utilizing the adaptive switching frequency control mode. The proposed controller has been implemented in a commercial 0.35μm 40-V BCD process, and the active chip area is 1.5×1.0 mm^2. The total error of the output voltage due to line and load variations is less than 4-1.7%.

关键词： constant voltage constant current dual-loop adaptive switching frequency

Effect of strontium nitride on the properties of Sr_2Si_5N_8:Eu^(2+) red phosphor

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Journal of Semiconductors 2011年第1期32卷 6-8页

作者：滕晓明梁超何锦华 Jiangsu Bree Optronics co.ltd.

The nitride phosphor Sr2Si5N8：Eu2＋ was synthesized by the high temperature solid-state method. The properties of Sr2Si8NsEu2＋ were discussed by X-ray diffraction （XRD） scanning electron microscope （SEM） and spectra analysis. The XRD pattern shows that the single phase produces when strontium nitride is a bit excessive. The SEM photo implies that the excessive strontium nitride works as a flux in the reaction system. The position of emission peak is also located at about 612 nm as strontium nitride is excessive. The luminescent intensity of the phosphor adding excessive strontium nitride is higher than that of the phosphor introducing stoichiometric strontium nitride. The optimized content of nitride strontium was 2.05 mol/mol for the obtained phosphor with excellent properties.

关键词： luminescence strontium nitride alkaline earth white LEDs rare earth

Anomaly Detection of controllable Electric Vehicles through Node Equation against Aggregation Attack

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computers, Materials & continua 2025年第1期82卷 427-442页

作者： Jing Guo Ziying Wang Yajuan Guo Haitao Jiang State Grid Jiangsu Electric Power co. Ltd.Research InstituteState Grid Corporation of ChinaNanjing211100China

The rapid proliferation of electric vehicle(EV)charging infrastructure introduces critical cybersecurity vulnerabilities to power grids *** study presents an innovative anomaly detection framework for EV charging stations,addressing the unique challenges posed by third-party aggregation *** approach integrates node equations-based on the parameter identification with a novel deep learning model,xDeepCIN,to detect abnormal data reporting indicative of aggregation *** employ a graph-theoretic approach to model EV charging networks and utilize Markov Chain Monte Carlo techniques for accurate parameter *** xDeepCIN model,incorporating a compressed Interaction Network,has the ability to capture complex feature interactions in sparse,high-dimensional charging *** results on both proprietary and public datasets demonstrate significant improvements in anomaly detection performance,with F1-scores increasing by up to 32.3%for specific anomaly types compared to traditional methods,such as wide&deep and DeepFM(Factorization-Machine).Our framework exhibits robust scalability,effectively handling networks ranging from 8 to 85 charging ***,we achieve real-time monitoring capabilities,with parameter identification completing within seconds for networks up to 1000 *** research contributes to enhancing the security and reliability of renewable energy systems against evolving cyber threats,offering a comprehensive solution for safeguarding the rapidly expanding EV charging infrastructure.

关键词： Anomaly detection electric vehicle aggregation attack deep cross-network