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Characteristics of water masses and bio-optical properties of the Bering Sea shelf during 2007–2009

Acta Oceanologica Sinica 2022年第10期41卷 140-153页

作者： yubin yao Tao Li Xingyuan Zhu Xiaoyu Wang College of Oceanic and Atmospheric Sciences Ocean University of ChinaQingdao266100China Pilot National Laboratory for Marine Science and Technology(Qingdao) Qingdao266237China Frontier Science Center for Deep Ocean Multispheres and Earth System(FDOMES)and Physical Oceanography Laboratory Ocean University of ChinaQingdao266100China

The hydrographic and bio-optical properties of the Bering Sea shelf were analyzed based on in-situ measurements obtained during four cruises from 2007 to *** to the temperature and salinity of the seawater,the spring water masses on the Bering Sea shelf were classified as the Alaskan Coast Water,Bering Sea Shelf Water,Anadyr Water,Spring Mixed Layer Water,Remnant Winter Water,and Winter Water,each of which had varying chlorophyll a *** them,the highest chlorophyll a concentration occurred in the nutrient-rich Anadyr Water((7.57±6.16)mg/m^(3) in spring).The spectrum-dependent diffuse attenuation coefficient(Kd(λ))of the water column for downwelling irradiance was also calculated,exhibiting a decrease at 412-555 nm and then an increase within the range of 0.17-0.48 m-1in ***,a strong correlation between the chlorophyll a concentration and the attenuation coefficient was found at visible wavelengths on the Bering Sea ***,the chlorophyll a concentration was higher on the northern shelf((5.18±3.78)mg/m^(3))than on the southern shelf((3.64±2.51)mg/m^(3)),which was consistent with the distribution of the attenuation ***,the consumption of nutrients by blooms resulted in minimum chlorophyll a concentration((0.78±0.51)mg/m^(3))and attenuation coefficient values in *** terms of the vertical structure,both the attenuation coefficient and the chlorophyll a concentration tended to reach maximum values at the same depth,and the depth of the maximum values increased as the surface temperature increased in ***,an empirical model was fitted with a power function based on the correlation between the chlorophyll a concentration and the attenuation coefficient at 412-555 *** addition,a spectral model was constructed according to the relationship between the attenuation coefficients at 490 nm and at other wavelengths,which provides a method for estimating the bio-optical properties of the Berin

关键词： diffuse attenuation coefficient water mass Bering Sea shelf chlorophyll a empirical model

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Miniature tunable Airy beam optical meta-device

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Opto-Electronic Advances 2024年第2期7卷 5-12页

作者： Jing Cheng Zhang Mu Ku Chen yubin Fan Qinmiao Chen Shufan Chen Jin yao Xiaoyuan Liu Shumin Xiao Din Ping Tsai Department of Electrical Engineering City University of Hong KongKowloonHong Kong SAR 999077China State Key Laboratory of Terahertz and Millimeter Waves City University of Hong KongKowloonHong Kong SAR 999077China Centre for Biosystems Neuroscienceand NanotechnologyCity University of Hong KongKowloonHong Kong SAR 999077China Ministry of Industry and Information Technology Key Lab of Micro-Nano Optoelectronic Information System Guangdong Provincial Key Laboratory of Semiconductor Optoelectronic Materials and Intelligent Photonic SystemsHarbin Institute of TechnologyShenzhen 518055China

Tunable Airy beams with controllable propagation trajectories have sparked interest in various fields,such as optical manipulation and laser *** research approaches encounter challenges related to insufficient compactness and integration feasibility,or they require enhanced tunability to enable real-time dynamic manipulation of the propagation *** this work,we present a novel method that utilizes a dual metasurface system to surpass these limitations,significantly enhancing the practical potential of the Airy *** approach involves encoding a cubic phase profile and two off-axis Fresnel lens phase profiles across the two *** validity of the proposed strategy has been confirmed through simulation and experimental *** proposed meta-device addresses the existing limitations and lays the foundation for broadening the applicability of Airy beams across diverse domains,encompassing light-sheet microscopy,laser fabrication,optical tweezers,etc.

关键词： metasurface miniature device tunable Airy beam tunable meta-device

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A Newton Power Flow for Study Purpose

A Newton Power Flow for Study Purpose

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2012 International Conference on Future Energy,Environment,and Materials

作者： yubin yao Benhua Gu Hong Zhao Zhengyu Xue Marine Engineering College Dalian Maritime University

The Newton power flow program which employing sparse matrix techniques needs less computer storage and running time, but makes it harder by modifying the program to adapt to further study such as power system security and continuation power flow. To meet study purpose a less complicated but fast Newton power flow algorithm is presented. A great deal of unnecessary computation is exempted in the algorithm simply by adding some selection actions in the procedure of the Jacobian matrix formation and that of Gauss elimination. The presented method needs a little more running time than the one using sparse matrix techniques, but it is much fast than the one without sparse matrix techniques and can satisfy the needs for study purpose. Experimental results validate the practicability of the presented method.

关键词： Newton power flow running time sparsity Jacobian matrix Gauss elimination

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A novel topology with controllable wideband baseband impedance for power amplifiers

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Frontiers of Information Technology & Electronic Engineering 2024年第2期25卷 308-315页

作者： yao yao Zhijiang DAI Mingyu LI School of Intelligent Technology and Engineering Chongqing University of Science and TechnologyChongqing400065China School of Microelectronics and Communication Engineering Chongqing UniversityChongqing400065China

This paper presents a novel topology to control the baseband impedance of a power amplifier(PA)to avoid performance deterioration in concurrent dual-band *** topology can avoid pure resonance of capacitors and inductors LC,which leads to a high impedance at some frequency ***,it can be applied to transmitters that are excited by broadband *** particular,by adjusting the circuit parameters and increasing stages,the impedance of the key frequency bands can be flexibly controlled.A PA is designed to support this design *** saturated output power is around 46.7 dBm,and the drain efficiency is>68.2%(1.8-2.3 GHz).Under concurrent two-tone excitation,the drain efficiency reaches around 40%even under 5.5 dB back-off power with the tone spacing from 10 MHz to 500 *** results demonstrate that the proposed topology is capable of controlling wideband baseband impedance.

关键词： Baseband impedance Concurrent dual-band Power amplifier

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考虑功频静特性的连续潮流法静态电压稳定分析

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电力系统自动化 1999年第15期23卷 37-39页

作者：姚玉斌朱发国陈学允哈尔滨工业大学电气工程系哈尔滨150001

在分析静态电压稳定的连续潮流法基础上，结合负荷的频率静态特性和发电机的频率调节特性，提出了考虑功频静特性的连续潮流法。分析与计算结果表明，由于在连续潮流法中考虑按功频静特性来分配发电机有功出力，符合电力系统的实际情况... 详细信息

在分析静态电压稳定的连续潮流法基础上，结合负荷的频率静态特性和发电机的频率调节特性，提出了考虑功频静特性的连续潮流法。分析与计算结果表明，由于在连续潮流法中考虑按功频静特性来分配发电机有功出力，符合电力系统的实际情况，因而求出的静态电压稳定的临界值具有合理性，且有实用价值。

关键词：连续潮流法静态电压稳定性电力系统频率静态

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Reinforcement learning based adaptive control for uncertain mechanical systems with asymptotic tracking

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Defence Technology（防务技术） 2024年第4期34卷 19-28页

作者： Xiang-long Liang Zhi-kai yao yao-wen Ge Jian-yong yao School of Mechanical Engineering Nanjing University of Science and TechnologyNanjing210094China College of Automation&College of Artificial Intelligence Nanjing University of Post and TelecommunicationNanjing210023China

This paper mainly focuses on the development of a learning-based controller for a class of uncertain mechanical systems modeled by the Euler-Lagrange *** considered system can depict the behavior of a large class of engineering systems,such as vehicular systems,robot manipulators and *** these systems are often characterized by highly nonlinear characteristics,heavy modeling uncertainties and unknown perturbations,therefore,accurate-model-based nonlinear control approaches become *** by the challenge,a reinforcement learning(RL)adaptive control methodology based on the actor-critic framework is investigated to compensate the uncertain mechanical *** approximation inaccuracies caused by RL and the exogenous unknown disturbances are circumvented via a continuous robust integral of the sign of the error(RISE)control *** from a classical RISE control law,a tanh(·)function is utilized instead of a sign(·)function to acquire a more smooth control *** developed controller requires very little prior knowledge of the dynamic model,is robust to unknown dynamics and exogenous disturbances,and can achieve asymptotic output ***,co-simulations through ADAMS and MATLAB/Simulink on a three degrees-of-freedom(3-DOF)manipulator and experiments on a real-time electromechanical servo system are performed to verify the performance of the proposed approach.

关键词： Adaptive control Reinforcement learning Uncertain mechanical systems Asymptotic tracking

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模糊控制有源电力滤波器在电力推进船舶中应用

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中国造船 2011年第1期52卷 193-200页

作者：赵红郭晨姚玉斌大连海事大学轮机工程学院大连116026 大连海事大学信息科学技术学院大连116026

电力推进船舶中,由于电力电子开关器件在推进电机变频调速装置中的广泛应用,使之在船舶电力系统中产生了大量的谐波,通常的解决方案是施加无源LC滤波器装置。近年来,克服了无源滤波器种种不足的有源电力滤波器(Active Power Filter,APF... 详细信息

电力推进船舶中,由于电力电子开关器件在推进电机变频调速装置中的广泛应用,使之在船舶电力系统中产生了大量的谐波,通常的解决方案是施加无源LC滤波器装置。近年来,克服了无源滤波器种种不足的有源电力滤波器(Active Power Filter,APF)得到了快速发展,该文将APF应用到电力推进船舶的电力系统中,并将模糊控制策略分别应用到并联型APF的电流跟踪环节和直流测电压控制环节。仿真结果表明,与常规的并联型APF相比,该文提出的基于模糊策略的APF具有更好的谐波抑制性能。

关键词：有源电力滤波器电力推进船舶模糊控制 MATLAB仿真

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可注射水凝胶微球治疗骨关节炎的实验研究

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中国修复重建外科杂志 2023年第8期37卷 918-928页

作者：姚裕斌魏刚丁婕崔文国温州医科大学附属第一医院骨科浙江温州325000 上海交通大学医学院附属瑞金医院、上海市伤骨科研究所、上海市中西医结合防治骨与关节病损重点实验室上海200025 南京航空航天大学医院南京210000

目的制备负载低聚倍半硅氧烷-双氯芬酸钠(polyhedral oligomeric silsesquioxane-diclofenac sodium,POSS-DS)纳米颗粒的甲基丙烯酰透明质酸(hyaluronic acid methacrylate,HAMA)水凝胶微球,对其进行表征并探究体内外生物学特性。方法以八巯基POSS(sulfhydryl POSS,POSS-SH)为纳米构筑平台,采用“点击化学”法将聚二乙醇和DS以化学键接枝其上,构建功能化纳米颗粒POSS-DS,并使用核磁共振波谱仪分析成分,透射电镜对形貌进行表征。为实现药物长期缓慢释放,将POSS-DS包载于HAMA中,通过微流控技术制备多功能水凝胶微球,即HAMA@POSS-DS;利用光镜及扫描电镜对其形态进行表征,观察体外降解及药物释放效率,采用细胞计数试剂盒8(cell counting kit 8,CCK-8)试剂盒及活/死染色法检测对软骨细胞增殖的影响;并构建软骨细胞炎症模型后用HAMA@POSS-DS进行处理,通过免疫荧光染色及实时荧光定量PCR检测相关炎症指标,即Ⅱ型胶原、聚集蛋白聚糖(aggrecan,AGG)、基质金属蛋白酶13(matrix metalloproteinase 13,MMP-13)、解聚蛋白样金属蛋白酶5(recombinant A disintegrin and metalloproteinase with thrombospondin 5,Adamts5)、速激肽1(recombinant tachykinin precursor 1,TAC1),以正常培养软骨细胞及未作处理的炎症模型分别作为对照组及空白组,进一步评估其抗炎性能。最后,通过构建大鼠膝关节骨关节炎模型,经X线片及Micro-CT检查,验证HAMA@POSS-DS对骨关节炎的治疗效果。结果POSS-DS纳米颗粒总体粒径均一,约100 nm。HAMA@POSSDS为不透明球体,粒径约100μm,呈多孔结构;体外降解周期为9周,期间缓释负载的POSS-DS。CCK-8试剂盒及活/死染色法检测显示HAMA@POSS-DS无明显细胞毒性,且其释放的POSS-DS对细胞增殖有促进作用(P<0.05)。软骨细胞抗炎实验中,HAMA@POSS-DS组Ⅱ型胶原mRNA相对表达量高于对照组和空白组、AGG mRNA相对表达量高于空白组、MMP-13、Adamts5以及TAC1 mRNA相对表达量低于空白组,上述差异均有统计学意义(P<0.05)。体内实验显示术后大鼠骨关节炎关节间隙宽度减小,但HAMA@POSS-DS可延缓关节间隙变窄进程,并改善关节周围骨赘增生情况(P<0.05)。结论HAMA@POSS-DS可有效改善局部炎症微环境,并显著促进软骨细胞增殖,有利于促进骨关节炎的软骨再生与修复。

关键词：低聚倍半硅氧烷水凝胶微球抗炎软骨再生骨关节炎

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Fresh-Keeping Decision and Coordination of Fresh Agricultural Product Supply Chain Considering Carbon Cap-and-Trade under Different Dominance

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Journal of Systems Science and Systems Engineering 2024年第1期33卷 30-51页

作者： Yang Yang Guanxin yao China Institute for Agricultural Equipment Industrial Development Jiangsu UniversityZhenjiang212013China Jiangsu Modern Logistics Research Base Yangzhou UniversityYangzhou225009China

In the context of low carbon,this paper discussed the impact of the carbon cap-and-trade policy on the fresh-keeping decision-making of two-echelon fresh agricultural product supply chains under different dominance,and designed cost-sharing contracts to coordinate the supply chain of fresh agricultural products dominated by suppliers and retailers *** results showed that:dominance has no effect on the fresh-keeping decision and total revenue of fresh agricultural product supply chain,but it affects the internal income distribution,and dominance does not always bring more benefits;the implementation of carbon cap-and-trade reduces the fresh-keeping decision-making of fresh agricultural products supply chain and reduces the free-rider income of followers;the role of higher carbon trading price is twofold,which not only brings about the speculation of leading enterprises,but also promotes the application of low-carbon technologies;consumers’high preference for freshness,low-cost and high-efficiency low-carbon technology are all conducive to improving the fresh-keeping efforts and benefits of the supply chain;cost-sharing contracts can coordinate the supply chain of fresh agricultural products.

关键词： Dominant power carbon cap-and-trade policy fresh agricultural product supply chain fresh-keeping decision-making

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Numerical investigation of non-uniform temperature fields for proppant and fluid phases in supercritical CO_(2)fracturing

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Particuology 2024年第7期90卷 149-163页

作者： Boyu Liu Jun yao Research Center of Multiphase Flow in Porous Media China University of Petroleum(East China)Qingdao 266000China

The non-uniform temperature distribution in supercritical CO_(2)(Sc-CO_(2))fracturing influences the density,viscosity,and volume expansion or shrinkage rate of Sc-CO_(2),impacting proppant *** study presents a coupled computational fluid dynamics-discrete element method and heat transfer model to examine the effects of proppant bed shape and the heat transfers of proppant-wall,proppant-fluid,and fluid-wall on the fluid and proppant temperature *** Sc-CO_(2)volume expansion is assessed under various temperature conditions by evaluating the volume-averaged Sc-CO_(2)*** factors,including proppant size,shape,thermal conductivity,concentration,temperature difference,and injection velocity,are carefully analyzed to elucidate their *** findings elucidate the existence of four distinct zones in the fluid temperature *** zone exhibits different magnitudes of temperature change under diverse conditions and undergoes dynamic transformations with the development of the proppant *** fluid-wall heat transfer and the fluid temperatures in Zones C and D are significantly subject to the fluid injection velocity(governing the heating duration),the temperature difference between fluid and formation(impacting the magnitude of heat flux),and the proppant bed shape(controlling the effective heating area).Additionally,the proppant-wall and proppant-fluid heat transfers determine the temperatures of both the proppant bed and the fluid within Zone B,showing a strong correlation with proppant thermal conductivity,proppant size,injection velocity,and temperature *** proposed coupled model provides valuable insights into the temperature distributions and flow behaviors of temperature-dependent fracturing fluids and proppants.

关键词： CFD-DEM Heat transfer Compressible fluid CO_(2)sequestration Proppant transport

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