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Gain adaptive tuning method for fiber Raman amplifier based on two-stage neural networks and double weights updates
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作者 MU Kuanlin WU Yue 《Optoelectronics Letters》 2025年第5期284-289,共6页
We present a gain adaptive tuning method for fiber Raman amplifier(FRA) using two-stage neural networks(NNs) and double weights updates. After training the connection weights of two-stage NNs separately in training ph... We present a gain adaptive tuning method for fiber Raman amplifier(FRA) using two-stage neural networks(NNs) and double weights updates. After training the connection weights of two-stage NNs separately in training phase, the connection weights of the unified NN are updated again in verification phase according to error between the predicted and target gains to eliminate the inherent error of the NNs. The simulation results show that the mean of root mean square error(RMSE) and maximum error of gains are 0.131 d B and 0.281 d B, respectively. It shows that the method can realize adaptive adjustment function of FRA gain with high accuracy. 展开更多
关键词 gain adaptive tuning connection weights error predicted target gains training connection weights unified nn gain adaptive tuning method double weights updates fiber raman amplifier fra
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Highly sensitive laser spectroscopy sensing based on a novel four-prong quartz tuning fork 被引量:1
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作者 Runqiu Wang Shunda Qiao +1 位作者 Ying He Yufei Ma 《Opto-Electronic Advances》 2025年第4期6-16,共11页
In this paper,a novel four-prong quartz tuning fork(QTF)was designed with enlarged deformation area,large prong gap,and low resonant frequency to improve its performance in laser spectroscopy sensing.A theoretical sim... In this paper,a novel four-prong quartz tuning fork(QTF)was designed with enlarged deformation area,large prong gap,and low resonant frequency to improve its performance in laser spectroscopy sensing.A theoretical simulation model was established to optimize the design of the QTF structure.In the simulation of quartz-enhanced photoacoustic spectroscopy(QEPAS)technology,the maximum stress and the surface charge density of the four-prong QTF demonstrated increases of 11.1-fold and 15.9-fold,respectively,compared to that of the standard two-prong QTF.In the simulation of light-induced thermoelastic spectroscopy(LITES)technology,the surface temperature difference of the four-prong QTF was found to be 11.4 times greater than that of the standard QTF.Experimental results indicated that the C_(2)H_(2)-QEPAS system based on this innovative design improved the signal-to-noise-ratio(SNR)by 4.67 times compared with the standard QTF-based system,and the SNR could increase up to 147.72 times when the four-prong QTF was equipped with its optimal acoustic micro-resonator(AmR).When the average time of the system reached 370 s,the system achieved a MDL as low as 21 ppb.The four-prong QTF-based C_(2)H_(2)-LITES system exhibited a SNR improvement by a factor of 4.52,and a MDL of 96 ppb was obtained when the average time of the system reached 100 s.The theoretical and experimental results effectively demonstrated the superiority of the four-prong QTF in the field of laser spectroscopy sensing. 展开更多
关键词 four-prong quartz tuning fork C2H2 detection quartz-enhanced photoacoustic spectroscopy light-induced thermoelastic spectroscopy
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Correction to: Tuning dual three-dimensional porous copper/graphite composite to achieve diversified utilization of copper current collector for lithium storage
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作者 Xia Ma Zhi-Jia Zhang +7 位作者 Jia-Min Wang Shi-Hao Sun Shao-Fei Zhang Shen Yuan Zhi-Jun Qiao Zhen-Yang Yu Jian-Li Kang Wei-Jie Li 《Rare Metals》 2025年第2期1409-1409,共1页
In the original publication, incomplete Fig. 1 has been published. The correct version of Fig. 1 is provided in this correction.
关键词 GRAPHITE tuning COMPOSITE three dimensional current collector POROUS DUAL COPPER
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Organelle-tuning condition robustly fabricates energetic mitochondria for cartilage regeneration
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作者 Xuri Chen Yunting Zhou +13 位作者 Wenyu Yao Chenlu Gao Zhuomin Sha Junzhi Yi Jiasheng Wang Xindi Liu Chenjie Dai Yi Zhang Zhonglin Wu Xudong Yao Jing Zhou Hua Liu Yishan Chen Hongwei Ouyang 《Bone Research》 2025年第3期671-685,共15页
Mitochondria are vital organelles whose impairment leads to numerous metabolic disorders.Mitochondrial transplantation serves as a promising clinical therapy.However,its widespread application is hindered by the limit... Mitochondria are vital organelles whose impairment leads to numerous metabolic disorders.Mitochondrial transplantation serves as a promising clinical therapy.However,its widespread application is hindered by the limited availability of healthy mitochondria,with the dose required reaching up to 109 mitochondria per injection/patient.This necessitates sustainable and tractable approaches for producing high-quality human mitochondria.In this study,we demonstrated a highly efficient mitochondriaproducing strategy by manipulating mitobiogenesis and tuning organelle balance in human mesenchymal stem cells(MSCs).Utilizing an optimized culture medium(mito-condition)developed from our established formula,we achieved an 854-fold increase in mitochondria production compared to normal MSC culture within 15 days.These mitochondria were not only significantly expanded but also exhibited superior function both before and after isolation,with ATP production levels reaching 5.71 times that of normal mitochondria.Mechanistically,we revealed activation of the AMPK pathway and the establishment of a novel cellular state ideal for mitochondrial fabrication,characterized by enhanced proliferation and mitobiogenesis while suppressing other energy-consuming activities.Furthermore,the in vivo function of these mitochondria was validated in the mitotherapy in a mouse osteoarthritis model,resulting in significant cartilage regeneration over a 12-week period.Overall,this study presented a new strategy for the off-the-shelf fabrication of human mitochondria and provided insights into the molecular mechanisms governing organelle synthesis. 展开更多
关键词 organelle tuning metabolic disordersmitochondrial transplantation osteoarthritis model MITOCHONDRIA mitobiogenesis mitochondriaproducing strategy cartilage regeneration AMPK pathway
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Enhancing Fire Detection with YOLO Models:A Bayesian Hyperparameter Tuning Approach
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作者 Van-Ha Hoang Jong Weon Lee Chun-Su Park 《Computers, Materials & Continua》 2025年第6期4097-4116,共20页
Fire can cause significant damage to the environment,economy,and human lives.If fire can be detected early,the damage can be minimized.Advances in technology,particularly in computer vision powered by deep learning,ha... Fire can cause significant damage to the environment,economy,and human lives.If fire can be detected early,the damage can be minimized.Advances in technology,particularly in computer vision powered by deep learning,have enabled automated fire detection in images and videos.Several deep learning models have been developed for object detection,including applications in fire and smoke detection.This study focuses on optimizing the training hyperparameters of YOLOv8 andYOLOv10models usingBayesianTuning(BT).Experimental results on the large-scale D-Fire dataset demonstrate that this approach enhances detection performance.Specifically,the proposed approach improves the mean average precision at an Intersection over Union(IoU)threshold of 0.5(mAP50)of the YOLOv8s,YOLOv10s,YOLOv8l,and YOLOv10lmodels by 0.26,0.21,0.84,and 0.63,respectively,compared tomodels trainedwith the default hyperparameters.The performance gains are more pronounced in larger models,YOLOv8l and YOLOv10l,than in their smaller counterparts,YOLOv8s and YOLOv10s.Furthermore,YOLOv8 models consistently outperform YOLOv10,with mAP50 improvements of 0.26 for YOLOv8s over YOLOv10s and 0.65 for YOLOv8l over YOLOv10l when trained with BT.These results establish YOLOv8 as the preferred model for fire detection applications where detection performance is prioritized. 展开更多
关键词 Fire detection smoke detection deep learning YOLO Bayesian hyperparameter tuning hyperparameter optimization Optuna
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Photon upconversion tuning through energy migration in lanthanides sensitized nanoparticles
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作者 Xingwen Cheng Jiangshan Luo Federico Rosei 《Nano Materials Science》 2025年第1期134-144,共11页
Lanthanide-sensitized upconverting nanoparticles(UCNPs)are widely studied because of their unusual optical characteristics,such as large antenna-generated anti-Stokes shifts,high photostability,and narrow emission ban... Lanthanide-sensitized upconverting nanoparticles(UCNPs)are widely studied because of their unusual optical characteristics,such as large antenna-generated anti-Stokes shifts,high photostability,and narrow emission bandwidths,which can be harnessed for a variety of applications including bioimaging,sensing,information security and high-level anticounterfeiting.The diverse requirements of these applications typically require precise control over upconversion luminescence(UCL).Recently,the concept of energy migration upconversion has emerged as an effective approach to modulate UCL for various lanthanide ions.Moreover,it provides valuable insights into the fundamental comprehension of energy transfer mechanisms on the nanoscale,thereby contributing to the design of efficient lanthanide-sensitized UCNPs and their practical applications.Here we present a comprehensive overview of the latest developments in energy migration upconversion in lanthanide-sensitized nanoparticles for photon upconversion tuning,encompassing design strategies,mechanistic investigations and applications.Additionally,some future prospects in the field of energy migration upconversion are also discussed. 展开更多
关键词 LANTHANIDES Upconversion tuning Energy migration Core-shell structures NANOPARTICLES
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Entropy tuning and artificial CEI synergistically enhance the stability and kinetics of P2-type layered oxide cathode for high-voltage sodium-ion batteries
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作者 Yingxinjie Wang Ziying Zhang +6 位作者 Kejian Tang Yongchun Li Guohao Li Jie Wang Zhenjun Wu Nan Zhang Xiuqiang Xie 《Journal of Energy Chemistry》 2025年第8期241-251,共11页
P2-type layered oxide Na_(2/3)Ni_(1/3)Mn_(2/3)O_(2)(NM)is a promising cathode material for sodium-ion batteries(SIBs).However,the severe irreversible phase transition,sluggish Na+diffusion kinetics,and interfacial sid... P2-type layered oxide Na_(2/3)Ni_(1/3)Mn_(2/3)O_(2)(NM)is a promising cathode material for sodium-ion batteries(SIBs).However,the severe irreversible phase transition,sluggish Na+diffusion kinetics,and interfacial side reactions at high-voltage result in grievous capacity degradation and inferior electrochemical performance.Herein,a dual-function strategy of entropy tuning and artificial cathode electrolyte interface(CEI)layer construction is reported to generate a novel P2-type medium-entropy Na_(0.75)Li_(0.1)Mg_(0.05)Ni_(0.18)Mn_(0.66)Ta_(0.01)O_(2)with NaTaO_(3)surface modification(LMNMT)to address the aforementioned issues.In situ X-ray diffraction reveals that LMNMT exhibits a near zero-strain phase transition with a volume change of only 1.4%,which is significantly lower than that of NM(20.9%),indicating that entropy tuning effectively suppresses irreversible phase transitions and enhances ion diffusion.Kinetic analysis and post-cycling interfacial characterization further confirm that the artificial CEI layer promotes the formation of a stable,thin NaF-rich CEI and reduces interfacial side reactions,thereby further enhancing ion transport kinetics and surface/interface stability.Consequently,the LMNMT electrode exhibits outstanding rate capability(46 mA h g^(−1)at 20 C)and cycling stability(89.5%capacity retention after 200 cycles at 2 C)within the voltage range of 2–4.35 V.The LMNMT also exhibits superior all-climate performance and air stability.This study provides a novel path for the design of high-voltage cathode materials for SIBs. 展开更多
关键词 Layered oxide cathodes Entropy tuning Artificial CEl HIGH-VOLTAGE Sodium-ion batteries
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Atomic Tuning for Perfect Catalysts
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《Bulletin of the Chinese Academy of Sciences》 2025年第1期13-13,共1页
Hydrogenation catalysts frequently impose a compromise between activity and selectivity,where maximizing one property inevitably diminishes the other.Researchers from the Dalian Institute of Chemical Physics(DICP)of t... Hydrogenation catalysts frequently impose a compromise between activity and selectivity,where maximizing one property inevitably diminishes the other.Researchers from the Dalian Institute of Chemical Physics(DICP)of the Chinese Academy of Sciences,in collaboration with scholars from University of Science and Technology of China and the Karlsruhe Institute of Technology in Germany,cracked this dilemma by engineering bimetallic catalysts with atomic precision-a breakthrough that boosts hydrogenation efficiency by 35-fold while maintaining pinpoint accuracy,resolving the stubborn activity-selectivity paradox. 展开更多
关键词 bimetallic catalysts engineering bimetallic catalysts atomic tuning activity selectivity paradox hydrogenation efficiency
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Fine-tuning of Hofmann-type metal-organic frameworks for highly efficient separation of C_(4) olefins
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作者 Jun-Xian Chen Xian-Xian Xiao +3 位作者 Libo Li Jinping Li Rui-Biao Lin Xiao-Ming Chen 《Chinese Journal of Structural Chemistry》 2025年第12期32-38,共7页
Separation of ternary C_(4) olefins(n-butene,iso-butene and 1,3-butadiene)is very challenging but crucial in the petrol-chemical industry due to their similar molecular sizes and properties.Herein,to optimize the sepa... Separation of ternary C_(4) olefins(n-butene,iso-butene and 1,3-butadiene)is very challenging but crucial in the petrol-chemical industry due to their similar molecular sizes and properties.Herein,to optimize the separation efficiency for separation of C_(4) olefins,a new Hofmann-type MOF,[Ni(piz)Ni(CN)_(4)](piz=piperazine)-isostructural to the typical one[Ni(pyz)Ni(CN)_(4)](pyz=pyrazine),has been synthesized by a facile method from aqueous solution.The pore size reduction of[Ni(piz)Ni(CN)_(4)](3.62A,in contrast to 3.85A in[Ni(pyz)Ni(CN)_(4)])results in negligible iso-butene(i-C_(4)H_(8))uptake(from 2.92 to 0.04 mmol g^(-1))whereas retaining significant uptake for 1,3-butadiene(1,3-C_(4)H_(6),1.96 mmol g^(-1))and n-butene(n-C_(4)H_(8),1.47 mmol g^(-1)),showing much higher uptake ratios of 1,3-C_(4)H_(6)/i-C_(4)H_(8)(47)and n-C_(4)H_(8)/i-C_(4)H_(8)(35)that outperform most of the benchmark porous materials for separating C_(4) olefins.Breakthrough experiments demonstrate successful separation of high-purity(99.9999%)i-C_(4)H_(8) and 1,3-C_(4)H_(6) from equimolar 1,3-C_(4)H_(6)/i-C_(4)H_(8),n-C_(4)H_(8)/i-C_(4)H_(8) and 1,3-C_(4)H_(6)/n-C_(4)H_(8)/i-C_(4)H_(8) mixtures. 展开更多
关键词 Metal-organic frameworks ISOSTRUCTURAL Gas separation C_(4)olefins Pore tuning
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Revealing the difference of Stark tuning rate between interface and bulk by surface-enhanced infrared absorption spectroscopy
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作者 Manyu Zhu Fei Liang +4 位作者 Lie Wu Zihao Li Chen Wang Shule Liu Xiue Jiang 《Chinese Chemical Letters》 2025年第2期433-436,共4页
Revealing the factors that affect the vibrational frequency of Stark probe at interface is a pre-requirement for evaluating the absolute interfacial electric field.Here using surface-enhanced infrared absorption(SEIRA... Revealing the factors that affect the vibrational frequency of Stark probe at interface is a pre-requirement for evaluating the absolute interfacial electric field.Here using surface-enhanced infrared absorption(SEIRA)spectroscopy,attenuated total reflection(ATR)spectroscopy and molecular dynamics(MD),we reveal the assembled C≡N at gold nanofilm exhibits a reduced Stark tuning rate(STR)referring to the vibrational frequency shift in response to electric field comparing with the bulk which was regulated by the electron transfer between S and Au.These findings lead to a deeper understanding of the vibrational Stark effect at the interface and provide guidance for improving the interface electric field theory. 展开更多
关键词 Surface-enhanced infrared spectroscopy Attenuated total reflection spectroscopy Vibrational stark effect Stark tuning rate Cyano group
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One-step quartz-MEMS micro-fabrication strategy for a grooved tuning fork
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作者 Yide Dong Chunyan Yin +1 位作者 Guangbin Dou Litao Sun 《Nanotechnology and Precision Engineering》 2025年第3期117-130,共14页
Grooved tuning forks with hierarchical structures have become some of the most widely used piezoelectric quartz microelectromechanical system devices;however,fabricating these devices requires multi-step processes due... Grooved tuning forks with hierarchical structures have become some of the most widely used piezoelectric quartz microelectromechanical system devices;however,fabricating these devices requires multi-step processes due to the complexity of etching of quartz,particularly in specific orientations of the crystal lattice.This paper proposes a one-step fabrication strategy that can form a complete hierarchical structure with only a single etching process using novel lithography patterns.The core principle of this strategy is based on the effect of the size of the groove patterns on quartz etching,whereby trenches of varying depths can be created in a fixed etching time by adjusting the width of the hard mask.Specifically,the device outline and grooved structure can be completed using a seamlessly designed etching pattern and optimized time.Furthermore,the etching structure itself influences the etching results.It was found that dividing a wide trench by including a wall to separate it into two narrow trenches significantly reduces the etching rate,allowing for predictable tuning of the etching rate for wider grooves.This effectively increases the usability and flexibility of the one-step strategy.This was applied to the manufacture of an ultra-small quartz grooved tuning fork resonator with a frequency of 32.768 kHz in a single step,increasing production efficiency by almost 45%and reducing costs by almost 30%compared to current methods.This has great potential for improving the productivity of grooved tuning fork devices.It can also be extended to the fabrication of other quartz crystal devices requiring hierarchical structures. 展开更多
关键词 Quartz crystal Quartz MEMS MICROFABRICATION Grooved tuning fork
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Achieving 40% room-temperature ODMR contrast in molecular systems through chemical tuning
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作者 Fushan Geng Bingwen Hu 《Magnetic Resonance Letters》 2025年第3期97-99,共3页
Optically detected magnetic resonance(ODMR)has emerged as a powerful technique for quantum sensing,enabling high-sensitivity detection of physical quantities even at room temperature.Solid-state defects,such as nitrog... Optically detected magnetic resonance(ODMR)has emerged as a powerful technique for quantum sensing,enabling high-sensitivity detection of physical quantities even at room temperature.Solid-state defects,such as nitrogen-vacancy(NV)centers in diamond,have demonstrated remarkable capabilities in this domain[1–4].However,these systems are limited by their rigid lattice structures and lack tunability. 展开更多
关键词 room temperature ODMR chemical tuning quantum sensingenabling detection physical quantities optically detected magnetic resonance odmr nitrogen vacancy centers quantum sensing molecular systems
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Continuously Tunable Thin-Film Lithium Niobate Optical Delay Line with 293 ps Tuning Range
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作者 Lv-Bin Song Yong Zheng +8 位作者 Yuan Ren Bo-Yang Nan Rui-Xue Liu Hao-Zong Zhong Lin Li Min Wang Jin-Ming Chen Rong-Bo Wu Ya Cheng 《Chinese Physics Letters》 2025年第9期62-67,共6页
We present a compact optical delay line(ODL)with wide-range continuous tunability on thin-film lithium niobate platform.The proposed device integrates an unbalanced Mach-Zehnder interferometer(MZI)architecture with du... We present a compact optical delay line(ODL)with wide-range continuous tunability on thin-film lithium niobate platform.The proposed device integrates an unbalanced Mach-Zehnder interferometer(MZI)architecture with dual tunable couplers,where each coupler comprises two 2×2 multimode interferometers and a MZI phase-tuning section.Experimental results demonstrate continuous delay tuning from 0 to 293 ps through synchronized control of coupling coefficients,corresponding to a 4 cm path difference between interferometer arms.The measured delay range exhibits excellent agreement with theoretical predictions derived from ODL waveguide parameters.This result addresses critical challenges in integrated photonic systems that require precise temporal control,particularly for applications in optical communications and quantum information processing,where a wide tuning range is paramount. 展开更多
关键词 continuous tunable thin film lithium niobate optical delay line wide range continuous tunability delay tuning optical delay line odl unbalanced Mach Zehnder interferometer synchronized control coupling coefficientscorresponding dual tunable couplers cm path difference interfe
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Effect of Weak Noise on the Frequency Tuning of Mouse Inferior Collicular Neurons 被引量:8
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作者 唐佳 皮建辉 +2 位作者 王丹 吴飞健 陈其才 《Zoological Research》 CAS CSCD 北大核心 2004年第3期191-197,共7页
In order to study the effect of weak noise on the sound signal extraction of mouse (Mus musculus Km) inferior collicular (IC) neurons from environments,we examined the changes in frequency tuning curves (FTCs) of 32 n... In order to study the effect of weak noise on the sound signal extraction of mouse (Mus musculus Km) inferior collicular (IC) neurons from environments,we examined the changes in frequency tuning curves (FTCs) of 32 neurons induced by a weak noise relative to 5 dB below minimum threshold of tone (reMT-5 dB) under free field stimulation conditions.The results were as follows:① There were three types of variations in FTCs,sharpened (34.4%),broadened (18.8%),and unaffected (46.9%),nevertheless,only the alteration of sharpened FTCs was statistically different.② Sharpness of frequency tuning induced by a reMT-5 dB noise was very strong.Q 10 and Q 30 of FTCs were increased by (34.42±17.04)% (P=0.026,n=11) and (46.34±22.88)% (P=0.009,n=7).③ The changes of inverse-slopes (ISs,kHz/dB) between high (IS high) and low (IS low) limbs of FTCs were dissymmetry.The IS high of FTCs decreased markedly (P=0.046,n=7),however,there was little change (P=0.947,n=7) in IS low.Our data revealed for the first time that the weak noise could sharpen frequency tuning and increase the sensitivity on the high frequency of sound signal in IC neurons of mouse. 展开更多
关键词 Weak white noise Sharpening frequency tuning Inferior collicular neurons MOUSE
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Detuning effect corrections using octupoles in diffraction-limited storage ring
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作者 Xuan Shouzhi Tian Shunqiang +2 位作者 Liu Xinzhong Gong Yihao Mao Linglong 《强激光与粒子束》 北大核心 2025年第7期72-82,共11页
The next generation of synchrotron radiation light sources features extremely low emittance,enabling the generation of synchrotron radiation with significantly higher brilliance,which facilitates the exploration of ma... The next generation of synchrotron radiation light sources features extremely low emittance,enabling the generation of synchrotron radiation with significantly higher brilliance,which facilitates the exploration of matter at smaller scales.However,the extremely low emittance results in stronger sextupole magnet strengths,leading to high natural chromaticity.This necessitates the use of sextupole magnets to correct the natural chromaticity.For the Shanghai Synchrotron Radiation Facility Upgrade(SSRF-U),a lattice was designed for the storage ring that can achieve an ultra-low natural emittance of 72.2 pm·rad at the beam energy of 3.5 GeV.However,the significant detuning effects,driven by high second-order resonant driving terms due to strong sextupoles,will degrade the performance of the facility.To resolve this issue,installation of octupoles in the SSRF-U storage ring has been planned.This paper presents the study results on configuration selection and optimization method for the octupoles.An optimal solution for the SSRF-U storage ring was obtained to effectively mitigate the amplitude-dependent tune shift and the second-order chromaticity,consequently leading to an increased dynamic aperture(DA),momentum acceptance(MA),and reduced sensitivity to magnetic field errors. 展开更多
关键词 Shanghai Synchrotron Radiation Facility Upgrade OCTUPOLE amplitude-dependent tune shift dynamic aperture momentum aperture
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Finite Element Simulation of the Vibratory Characteristics for Quartz Tuning Fork Gyroscope 被引量:2
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作者 王莹 孙雨南 秦秉坤 《Journal of Beijing Institute of Technology》 EI CAS 2002年第2期155-158,共4页
The micro quartz crystal tuning fork gyroscope is a new type of vibratory gyroscope. The gyroscope should be analyzed and simulated early in the design stage in order to offer reliable basis for design and to shorten ... The micro quartz crystal tuning fork gyroscope is a new type of vibratory gyroscope. The gyroscope should be analyzed and simulated early in the design stage in order to offer reliable basis for design and to shorten the period of development. Thus the vibratory characteristics of the gyroscope is simulated with the finite element method of coupled field. The optimum exciting frequency and the factors which influence the gyroscope sensitivity are determined. The method for adjusting the frequency deviation between driving and detecting modes is also proposed. 展开更多
关键词 quartz gyroscope tuning fork finite element method
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A New Tuning Method for Two-Degree-of-Freedom Internal Model Control under Parametric Uncertainty 被引量:10
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作者 Juwari Purwo sutikno Badhrulhisham Abdul aziz +1 位作者 Chin Sim yee Rosbi Mamat 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2013年第9期1030-1037,共8页
Internal model control (IMC) yields very good performance for set point tracking, but gives sluggish response for disturbance rejection problem. A two-degree-of-freedom IMC (2DOF-IMC) has been developed to overcom... Internal model control (IMC) yields very good performance for set point tracking, but gives sluggish response for disturbance rejection problem. A two-degree-of-freedom IMC (2DOF-IMC) has been developed to overcome the weakness. However, the setting of parameter becomes a complicated matter if there is an uncertainty model. The present study proposes a new tuning method for the controller. The proposed tuning method consists of three steps. Firstly, the worst case of the model uncertainty is determined. Secondly, the parameter of set point con- troller using maximum peak (Mp) criteria is specified, and finally, the parameter of the disturbance rejection con- troller using gain margin (GM) criteria is obtained. The proposed method is denoted as Mp-GM tuning method. The effectiveness of Mp-GM tuning method has evaluated and compared with IMC-controller tuning program (IMCTUNE) as bench mark. The evaluation and comparison have been done through the simulation on a number of first order plus dead time (FOPDT) and higher order processes. The FOPDT process tested includes processes with controllability ratio in the range 0.7 to 2.5. The higher processes include second order with underdarnped and third order with nonminimum phase processes. Although the two of higher order processes are considered as difficult processes, the proposed Mp-GM tuning method are able to obtain the good controller parameter even under process uncertainties. 展开更多
关键词 tuning 2DOF-IMC model uncertainty dead time process Mp-GM tuning IMCTUNE
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A Real Time Self-Tuning Motion Controller for Mobile Robot Systems 被引量:6
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作者 Mohamed Boukens Abdelkrim Boukabou Mohammed Chadli 《IEEE/CAA Journal of Automatica Sinica》 EI CSCD 2019年第1期84-96,共13页
This paper proposes an intelligent controller for motion control of robotic systems to obtain high precision tracking without the need for a real-time trial and error method.In addition, a new self-tuning algorithm ha... This paper proposes an intelligent controller for motion control of robotic systems to obtain high precision tracking without the need for a real-time trial and error method.In addition, a new self-tuning algorithm has been developed based on both the ant colony algorithm and a fuzzy system for real-time tuning of controller parameters. Simulations and experiments using a real robot have been addressed to demonstrate the success of the proposed controller and validate the theoretical analysis. Obtained results confirm that the proposed controller ensures robust performance in the presence of disturbances and parametric uncertainties without the need for adjustment of control law parameters by a trial and error method. 展开更多
关键词 Learning and adaptive SYSTEMS motion CONTROL METAHEURISTIC robust CONTROL real-time tuning SELF-tuning WHEELED mobile robot
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Tuning of the textural features and acidic properties of sulfated mesoporous lanthana-zirconia solid acid catalysts for alkenylation of diverse aromatics to their corresponding α-arylstyrenes
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作者 赵忠奎 冉金凤 +2 位作者 郭永乐 苗博元 王桂茹 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2016年第8期1303-1313,共11页
The textural features and acidic properties of sulfated mesoporous lanthana‐zirconia solid acids (SO42?/meso‐La0.1Zr0.9Oδ) were efficiently tuned by modifying the conditions used to prepare the meso‐La0.1Zr0.9O... The textural features and acidic properties of sulfated mesoporous lanthana‐zirconia solid acids (SO42?/meso‐La0.1Zr0.9Oδ) were efficiently tuned by modifying the conditions used to prepare the meso‐La0.1Zr0.9Oδcomposites, such as the molar ratio of the template to La and Zr metal ions (Nt/m), molar ratio of ammonia to La and Zr metal ions (Na/m), hydrothermal temperature (Thydro), and hy‐drothermal time (thydro). The effect of the textural features and acidic properties on the catalytic performance of solid acid catalysts for alkenylation of p‐xylene with phenylacetylene was investi‐gated. Various characterization techniques such as N2 physisorption, X‐ray diffraction, NH3 temper‐ature‐programmed desorption, and thermogravimetric analysis were employed to reveal the rela‐tionship between the nature of catalyst and its catalytic performance. It was found that the catalytic performance significantly depended on the textural features and acidic properties, which were strongly affected by preparation conditions of the meso‐La0.1Zr0.9Oδcomposite. Appropriate acidic sites and high accessibility were required to obtain satisfactory catalytic reactions for this reaction. It was also found that the average crystallite size of t‐ZrO2 affected by the preparation conditions had significant influence on the ultrastrong acidic sites of the catalysts. The optimized SO42?/meso‐La0.1Zr0.9Oδcatalyst exhibited much superior catalytic activity and coke‐resistant stabil‐ity. Moreover, the developed SO42?/meso‐La0.1Zr0.9Oδcatalyst demonstrated excellent catalytic per‐formance for alkenylation of diverse aromatics with phenylacetylene to their correspondingα‐arylstyrenes. Combining the previously established complete regeneration of used catalysts by a facile calcination process with the improved catalytic properties, the developed SO42?/meso‐La0.1Zr0.9Oδ solid acid could be a potential catalyst for industrial production ofα‐arylstyrenes through clean and atom efficient solid‐acid‐mediated Friedel‐Crafts alkenylation of diverse aromatics with phenylacetylene. 展开更多
关键词 Mesoporous solid acid ALKENYLATION Clean synthesis Alkenyl aromatics Textural and acidic properties tuning
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A Design of a PID Self-Tuning Controller Using LabVIEW 被引量:1
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作者 Mohammad A. K. Alia Tariq M. Younes Shibel Al Subah 《Journal of Software Engineering and Applications》 2011年第3期161-171,共11页
In this paper a trial has been made to design a simple self-tuning LabVIEW-based PID controller. The controller uses an open-loop relay test, calculates the tuned parameters in an open loop mode of operation before it... In this paper a trial has been made to design a simple self-tuning LabVIEW-based PID controller. The controller uses an open-loop relay test, calculates the tuned parameters in an open loop mode of operation before it updates controller parameters and runs the process as a closed-loop system. The controller reacts on a persistent offset error value as a result of load disturbance or a set point change. Practical results show that such a controller may be recommended to control a variety of industrial processes. A GUI was developed to facilitate control-mode selection, the setting of controller parameters, and the display of control system variables. GUI makes it possible to put the controller in manual or self-tuning mode. 展开更多
关键词 PID Control MANUAL tuning SELF-tuning OPEN-LOOP RELAY Test Process Variable System OFFSET Error
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