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A shortcut to marking 3D target curves on curved surface via a galvanometric laser scanner

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Chinese Journal of Aeronautics 2019年第6期32卷 1555-1563页

作者： Junchao TU Mingang WANG liyan zhang College of Mechanical and Electrical Engineering Nanjing University of Aeronautics and Astronautics

Marking arbitrary three-dimensional(3D) target curves on given objects with curved surface is required in many industrial fields, such as fabric prepreg placement in composite material part fabrication, product assembly, surface painting for decoration, etc. A shortcut to the solution of this intractable problem is proposed by utilizing a galvanometric laser scanner(GLS) with the aid of a camera. Without using the existing tedious GLS calibration procedures,the proposed method directly establishes a mapping between the 3D coordinates of the laser spots on the object surface and the control voltages of the scanner. A single-hidden layer feedforward neural network(SLFN) is employed to model the mapping. By projecting a dense grid of laser spots on the object to be marked and simultaneously taking only one image, the SLFN model is trained in minutes via a linear solving mechanism. Experiments demonstrate that the trained SLFN model has a good generalization performance for marking 3D target curves. The 3D laser marking errors on experimental objects are less than 0.5 mm. The proposed method is especially suitable for on-site use and can be conveniently extended to multiple GLSs for marking large complex objects.

关键词： Calibration Fabric prepreg placement Laser materials processing Laser scanner Three-dimensional laser marking

Yb^(3+)-doped Fluorophosphate Glass with High Cross Section and Lifetime

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Journal of Materials Science & Technology 2010年第10期26卷 921-924页

作者： liyan zhang Yuxin Leng Junjie zhang Lili Hu Key Laboratory of Materials for High Power Laser Shanghai Institute of Optics and Fine Mechanics Chinese Academy of Sciences Shanghai 201800 China

Yb3＋ doped fluorophosphate （FP/Yb） glasses with emission cross section and fluorescence lifetime as high as 0.8388×10-20 cm 2 and 2.3 ms were developed,and AlF3 content is proved to decrease the lifetime *** scale glass casting procedure shows high Tx-Tg doesn t make better casting crystallization stability in *** Yb laser is difficult to be obtained in FP glass,a 230 mw laser was still achieved from 2 mm thick samples under 976 nm LD excitation because of the large gain parameter（σemiτf） of the FP/Yb *** test also proved the relationship between laser output and gain *** with its wide and flat effective gain property,this FP/Yb glass is a practical new potential material for low power ultra-short pulse application.

关键词： FP15/Yb glass Crystallization stability Gain parameter

Model predictive control with fractional-order delay compensation for fast sampling systems

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Science China(Information Sciences) 2021年第7期64卷 165-180页

作者： Ze ZHOU Zhitao LIU Hongye SU liyan zhang State Key Laboratory of Industrial Control Technology Institute of Cyber-Systems and ControlZhejiang University School of Automation Wuhan University of Technology

Model predictive control(MPC) is widely used in fast sampling systems owing to its fast regulating ability. However, the sampling delay is a key issue and tends to be a fractional multiple of the sampling period. If the fractional-order delay is not accurately offset, the controller output will exhibit errors, thus resulting in oscillations in controlled system. Moreover, the MPC delay compensation algorithm is limited to the computation time. To address the problems of fractional delay and computational burden in fast sampling systems, we propose a new method to compensate for the fractional-order sampling ***, we use a finite-impulse-response fractional delay filter based on a Lagrange interpolation polynomial to approximate the fractional portion. Moreover, we prove that high accuracy and simplicity can be ensured when the polynomial order is one. Then, we estimate the current state variable using the delayed sampling signal and control signals of past moments. Further, we obtain the current control signal according to the estimated state variable. By considering the simultaneous existence of computational and sampling delays,a full compensation strategy is proposed. Computational simulation results validate the proposed MPC algorithm with fractional-order delay compensation and demonstrate its advantages.

关键词： model predictive control fast sampling systems sampling delay fractional-order Lagrange interpolation polynomial

Multi-objective optimization for 10-kW rated power dynamic wireless charging systems of electric vehicles

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Science China(Information Sciences) 2022年第10期65卷 178-195页

作者： Ze ZHOU Zhitao LIU Hongye SU liyan zhang State Key Laboratory of Industrial Control Technology Institute of Cyber-Systems and Control Zhejiang University School of Automation Wuhan University of Technology

In this paper, we propose a method to optimize the output power, efficiency, and cost of the dynamic wireless charging(DWC) system of electric vehicles by using the transmitting coil spacing as the decision variable. In a set of transmitting equipment, we adopt a structure with two transmitting networks in parallel and derive loss models. The expressions of the output power and efficiency of the DWC system are obtained by data fitting. In addition, combined with the proposed cost function, we construct a multiobjective optimization problem on output power, efficiency, and cost. Due to the complexity of the objective function, it is difficult to solve the problem by the analytic method, and thus we propose a constrained adaptive particle swarm optimization(CAPSO) algorithm with high accuracy to solve the problem. Finally,the simulation results verify the feasibility of the proposed model. The advantages of the proposed CAPSO algorithm and the optimization results under different weight combinations are presented.

关键词： dynamic wireless charging electric vehicles multi-objective optimization constrained adaptive particle swarm optimization

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Levels and patterns of genetic variation in Pampus minor:Assessment of a mitochondrial DNA control region sequence

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Acta Oceanologica Sinica 2021年第4期40卷 74-83页

作者： Yuan Li liyan zhang ling zhang Cheng Liu Longshan Lin Third Institute of Oceanography Ministry of Natural ResourcesXiamen 361005China Fujian Institute of Oceanography Xiamen 361013China Fisheries College Jimei UniversityXiamen 361021China

Pampus minor is an important commercial *** to the similarity of external morphological characteristics among the genus Pampus species,*** has often been identified as the juvenile group of both *** and *** little genetic background on this species is known,this study was based on control region sequences and provided the first evaluation of the genetic signature of 264 individuals of *** from 11 populations along the coasts of China and *** results indicate high genetic haplotype diversity and low nucleotide diversity in this ***,two differentiated haplotype lineages were identified in the *** ***,phylogenetic structures corresponding to the geographical locations were unable to be *** of molecular variance identified a vast majority of the genetic variation occurring within populations.F-statistic test value(FST)of pairwise indicated that great differences existed between the Chinese and Malaysian *** *** the Chinese populations,the genetic differences were insignificant with the exception of the Xiamen population,which is a marginal *** the late Pleistocene,a population expansion of *** *** expanded populations originated from the glacial refugium in the South China Sea and then rapidly occupied and adapted to their new *** results of this study provide genetic information for ensuring the protection and management of *** resources.

关键词： phylogeography South China Sea Pampus minor genetic diversity genetic differentiation

Chiral Coordination Metallacycles/Metallacages for Enantioselec-tive Recognition and Separation

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Chinese Journal of Chemistry 2021年第8期39卷 2273-2286页

作者： liyan zhang Huiping Liu Guozan Yuan Ying-Feng Han School of Chemistry and Chemical Engineering Institute of Materials Science and EngineeringAnhui University of TechnologyMaanshanAnhui 243032China Key Laboratory of Synthetic and Natural Functional Molecule of the Ministry of Education College of Chemistry and Materials ScienceNorthwest UniversityXi'anShaanxi 710127China

In recent years,chiral discrete supramolecular coordination complexes have attracted increasing interest as simple enzyme mimetics owing to their aesthetic architectures and potential applications in chiral *** review summarizes the recent advances on chiral coordination metallacy-cles/metallacages with inherent cavities for enanti on selective recog nition and separation,including their design principles and synthesis,the in troduc-tion of chirality and functionality,structural adaptability,and host-guest bonding in enantioselective ***,the perspectives on the remain-ing challenges and future opportunities are presented.

关键词： Chirality Metallacycles Metallacages Molecular recognition Chiral resolution

A Highly Efficient Ni/Al_(2)O_(3)-LaO_(x) Catalyst for the Reductive Amination of Furfural to Furfurylamine:the Promoting Effect of La

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Chemical Research in Chinese Universities 2024年第1期40卷 36-46页

作者： YANG Yinze zhang liyan ZHOU Leilei CHENG Haiyang ZHAO Fengyu State Key Laboratory of Electroanalytical Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022P.R.China School of Applied Chemistry and Engineering University of Science Technology of ChinaHefei 230026P.R.China Jilin Province Key Laboratory of Green Chemistry and Process Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022P.R.China

The reductive amination of furfural to furfurylamine is an important and still challenging topic in the field of biomass conversion. In this work, we prepared a series of Ni/Al_(2)O_(3)-LaO_(x) catalysts by co-precipitation method, the role of La played in promoting the catalytic performances of reductive amination furfural was discussed based on the changes in the electronic state of Ni species, acidity, and Ni particle size. The catalytic activity and the selectivity of furfurylamine are highly dependent on the surface properties and the structure of the catalyst. The addition of La promoted the amount of strong acidic sites and the H2dissociation and spillover on the surface, thus inducing the improvement of the catalytic activity and furfurylamine selectivity. The Ni/Al_(2)O_(3)-0.5LaO_(x)catalyst with suitable acid sites gave a high yield of furfurylamine (94.9%) under mild reaction conditions. Moreover, the catalyst could be recycled five times without significant loss in activity. The Ni/Al_(2)O_(3)-LaO_(x) catalyst is of great promise in the production of amines via reductive amination reaction.

关键词： Reductive amination Furfural Nickel catalyst Furfurylamine Lanthanum

Catalytic reductive amination of furfural to furfurylamine on robust ultra-small Ni nanoparticles

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Nano Research 2023年第3期16卷 3719-3729页

作者： Yinze Yang Leilei Zhou Xinchao Wang liyan zhang Haiyang Cheng Fengyu Zhao State Key Laboratory of Electroanalytical Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China School of Applied Chemistry and Engineering University of Science and Technology of ChinaHefei 230026China Jilin Province Key Laboratory of Green Chemistry and Process Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China

The synthesis of primary amines via reductive amination in the presence of NH_(3)and H_(2),as a green and sustainable process,has attracted much *** this paper,we prepared series of Ni/SiO_(2)catalysts with deposition-precipitation and impregnation methods,and their catalytic performances on the reductive amination of a biomass derived compound of furfural to produce furfurylamine were *** catalytic activity and the yield were correlated to the structure and the surface properties of catalysts *** Ni/SiO_(2)is of high Lewis acidity and small Ni particle with numerous large Ni flat step surface showed high activity and selectivity,it afforded a reaction rate of 12.8 h^(−1)and a high yield to furfurylamine around 98%.These results are superior to the most non-noble metal catalysts reported so ***,the reaction route was examined with the unit control reactions of the *** produce furfurylamine selectively,the most suitable catalyst should have the moderate but not the highest activity in activation of hydrogen and hydrogenation in the reductive amination of *** work provides some useful information for the catalytic reductive amination of aldehydes both in the design of catalyst and the reaction route.

关键词： Ni nanoparticle reductive amination furfural furfurylamine

Fish diversity and molecular taxonomy in the Prydz Bay during the 29th CHINARE

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Acta Oceanologica Sinica 2018年第8期37卷 15-20页

作者： LI Yuan zhang liyan SONG Puqing zhang Ran WANG Liangming LIN Longshan Third Institute of Oceanography State Oceanic AdministrationXiamen 361005China Fujian Institute of Oceanography Xiamen 361013China

In 2013, the 29th Chinese National Antarctic Research Expedition（CHINARE） prospected the Prydz Bay on the Antarctic continental shelf, and the Chinese R/V Xuelong icebreaker sampled all of the examined locations. The nature of Antarctic fish diversity in the high-latitude Prydz Bay is virtually unknown, and the accuracy of relevant estimates has not been established. Thus, it is necessary to evaluate this diversity and propose protective measures. In total, ninety-nine specimens were collected from various locations. To overcome uncertainties associated with identifying species based on morphology, DNA barcoding（COI gene） was employed to reconstruct phylogenetic relationships with delimited references from NCBI. Twenty-two species representing six families were unambiguously identified from a neighbor-joining（NJ） tree and barcoding gaps. With the morphological identification, thirteen species were identified correctly, five species were identified correctly at the genus level, and four species were identified at the close sister species level. Notothenioid dominance was not evident in the Prydz Bay, in contrast to other published studies. The low species diversity and catch biomass during this CHINARE were severely constrained by limited fishing methods and localized sites, which led to biased underestimation. Our analyses indicate that DNA barcoding is an effective tool for the identification of fish species in the Prydz Bay. The identification and distribution of Antarctic fish should be an integral component of understanding Antarctic fish biodiversity and biogeography, and large-scale studies are necessary for the further taxonomic identification of Antarctic fish.

关键词： DNA barcoding Prydz Bay Antarctic fish phylogenetic relationship barcoding gap