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The Time-Dependent Von Kármán Shell Equation as a Limit of Three-Dimensional Nonlinear Elasticity

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Journal of Systems Science & Complexity 2021年第2期34卷 465-482页

作者： QIN Yizhao yao peng-Fei Department of Mathematical Science Tsinghua UniversityBeijing 100084China Key Laboratory of Systems and Control Institute of Systems ScienceAcademy of Mathematics and Systems ScienceChinese Academy of SciencesBeijing 100190China School of Mathematical Sciences University of Chinese Academy of SciencesBeijing 100049China

The asymptotic behaviour of solutions of three-dimensional nonlinear elastodynamics in a thin shell is considered,as the thickness h of the shell tends to *** the appropriate scalings of the applied force and of the initial data in terms of h,it’s verified that three-dimesional solutions of the nonlinear elastodynamic equations converge to solutions of the time-dependent von Kármán equations or dynamic linear equations for shell of arbitrary geometry.

关键词： Nonlinear elasticity thin shell time-dependent von Kármán equations

Cooperative Sampling Path Planning of Underwater Glider Fleet with Simultaneous Launch and Recovery

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Journal of Ocean University of China 2023年第4期22卷 975-982页

作者： ZANG Wenchuan SONG Dalei yao peng College of Information Science and Engineering Ocean University of ChinaQingdao 266000China Department of Electronics Information and BioengineeringPolitecnico di MilanoMilan 20133Italy College of Engineering Ocean University of ChinaQingdao 266000China

As low-cost and highly autonomous ocean observation platforms,underwater gliders encounter risks during their launch and recovery,especially when coordinating multi-glider *** work focuses on cooperative path planning of an underwater glider fleet with simultaneous launch and recovery to enhance the autonomy of sampling and reduce deployment ***,the gliders collaborate to achieve sampling considering the specified routines of *** overall paths to be planned are divided into four rectangular parts with the same starting point,and each glider is assigned a local sampling route.A clipped-oriented line-of-sight algorithm is proposed to ensure the coverage of the desired *** pitch angle of the glider is selected as the optimizing parameter to coordinate the overall progress considering the susceptibility of gliders to currents and the randomness of paths produced by complex navigational ***,a multi-actuation deep-Q network algorithm is proposed to ensure simultaneous launch and *** results demonstrate the acceptable effectiveness of the proposed method.

关键词： underwater glider fleet cooperative sampling path planning simultaneous launch and recovery clipped-oriented line-ofsight multi-actuation deep-Q network

Profile error compensation in precision grinding of ellipsoid optical surface

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Chinese Journal of Aeronautics 2021年第4期34卷 115-123页

作者： Shimeng YU Jiahao ZHU peng yao Chuanzhen HUANG Center for Advanced Jet Engineering Technologies(CaJET) School of Mechanical EngineeringShandong UniversityJinan 250061China Key Laboratory of High Efficiency and Clean Mechanical Manufacture Shandong UniversityMinistry of EducationJinan 250061China

Optical glass elements with the ellipsoidal surface are used in many critical aerospace instruments,such as satellites,telescope and *** optical performance is mainly affected by profile accuracy and surface *** this paper,a rectangular ellipsoid surface is precisely ground on a BK7 optical glass blank by grating scanning grinding path with a three-axis CNC precision surface grinder.A profile error compensation procedure for ellipsoidal grinding is proposed based on the error analysis about the primary error sources in the XY and YZ projection planes during the grinding *** mathematical prediction models of the wheel arc profile error,the measurement and wear error of the grinding wheel radiuses are *** applying the proposed error compensation procedure,the profile accuracy of the ellipsoidal surface was improved from 4 lm to 2 lm in the XY plane,and improved from 15 lm to 5 lm in the YZ plane.

关键词： Aspheric lens Ellipsoid surface Error compensation Grinding wheel truing Precision grinding

Pigment signatures of some diatoms isolated from China seas

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Acta Oceanologica Sinica 2006年第1期25卷 108-118页

作者： yao peng YU Zhigang DENG Chunmei College of Chemistry and Chemical Engineering Ocean University of China Qingdao 266003 China

The photosynthetic pigments of 12 species （14 strains） of cultured diatoms from six genera under specific conditions were examined by the HPLC. The diatom genera were Skeletonema, Thalassiosira, Chaetoceros, Nitzschla, Phaeodactylum and Meuniera. All strains were isolated from China seas and most of them were from the Jiaozhou Bay, China. Fifteen pigments were identified and eight of them were various chlorophyll a derivatives. Chlorophyll a, c2 and c1 and the carotenoids fucoxanthin, diadinoxanthin, diatoxanthin and β, β-carotene existed in all species. The ratios of each pigment to chlorophyll a were compared with the results in literatures. The pigment ratios of this study generally fall within the ranges reported by the literatures although the maximum ratio of fucoxanthin to chlorophyll a was higher and the ratios of chlorophyll c and diatoxanthin to chlorophyll a were low. The pigment ratios are useful to understanding the pigment signatures of diatoms in the Jiaozhou Bay, China, and to setting up the chemotaxonomic method of phytoplankton in these sea areas.

关键词： diatoms pigment HPLC ratio Jiaozhou Bay

CURING PROCESS OF PHOTOPOLYMER RESIN BOND DIAMOND TOOLS

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Chinese Journal of Mechanical Engineering 2007年第3期20卷 6-8页

作者： GAO Tao peng Wei yao Chunyan Ministry of Education Key Laboratory of Mechanical ManufactureZhejiang University of Technology Hangzhou 310014 China

Analytical simulation and corresponding proof-test are adopted to study the principle of the curing process of photopolymer resin diamond tools. The influence of the diamond as abrasives in photopolymer resin owing to the absorptivity of the diamond for the UV light on the photopolymer resin curing process is discussed. Based on the above, a kind of diamond tool—dicing blade is selected to analyze the curing process of photopolymer bond diamond tools. An analytical model of curing process is developed and a correlation curve between the depth of polymerization of the photopolymer resin diamond tools and the exposure time to represent the curing process of photopolymer bond dicing blade. A test is done to proof-test the validity of the analytical model and the correlation curve. The simulated data fit the experimental results, which demonstrates the analytical models and numerical algorithm are of high reliability. The analytical simulation method could possibly be used to optimize the curing cycle and improve the quality of the photopolymers resin bond diamond tools.

关键词： Photopolymer Curing process Simulation Diamond tools

Synthesis of reusable NH_(2)-MIL-125(Ti)@polymer monolith as efficient adsorbents for dyes wastewater remediation

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Green Chemical Engineering 2023年第4期4卷 439-447页

作者： peng yao Yang Liu Xue Tang Shuxiang Lu Zhen Li Yue yao College of Chemical Engineering and Materials Science Tianjin University of Science and TechnologyTianjin300457China

NH_(2)-MIL-125(Ti)is a Ti-MOFs(MOFs:metal-organic frameworks)with high adsorption properties and is therefore widely used for wastewater ***,the powdered MOF material suffers from the disadvantages of being difficult to separate and being potentially wasted due to easy agglomeration,which limits its application in practical ***,a mesoporous Ti-MOF/polymer(PEG,PVA,and PAM)monolithic material was prepared by freeze casting in liquid nitrogen(-196℃)as an adsorbent for wastewater *** composites could be easily picked up with tweezers and used for recovery *** results such as XRD,BET,FT-IR,and SEM proved the successful synthesis of Ti-MOF/*** tests using 100 mg/L methylene blue(MB)simulated wastewater showed that the Ti-MOF/PEG monolithic material had the best adsorption *** order of adsorption was Ti-MOF@PEG10(747.4 mg/g)>Ti-MOF@PVA10(687.4 mg/g)>Ti-MOF@PAM10(633.7 mg/g)>NH_(2)-MIL-125(Ti)(571.4 mg/g).The effects of polymer dosage,different pollutants(methylene blue,methyl orange,indigo,actual textile wastewater),pH,anions,and cations on the adsorption effect of Ti-MOF/polymer were also *** was demonstrated that all the above pollutants were well adsorbed by this Ti-MOF/polymer in the pH range *** adsorption isotherms and kinetic data are fully consistent with the Langmuir and pseudo-secondary *** suggests that the adsorption between the pollutant and the adsorbent is a chemical *** studies indicate that the adsorption process is exothermic and *** work provides the potential methods to fabricate Ti-MOF/polymer monolith to avoid the pollution from powdery adsorbents that could be practical applications.

关键词： Adsorption NH_(2)-MIL-125(Ti) Freeze-casting method Methylene blue Polymers Liquid nitrogen

Structure-based Screening for the Non-zinc-chelating Selective MMP-13 Inhibitors of Natural Products

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Chinese Journal of Structural Chemistry 2020年第11期39卷 1990-2000页

作者： ZOU Qing GAO Qiu-Shuang yao peng yao Qi-Zheng ZHANG Ji Department of Physical Chemistry China Pharmaceutical UniversityNanjing 210009China State Key Laboratory of Natural Medicines China Pharmaceutical UniversityNanjing 210009China School of Pharmacy China Pharmaceutical UniversityNanjing 210009China

Matrix metalloproteinase-13(MMP-13) has been considered as a promising therapeutic target for osteoarthritis. In this work, the experimental crystal structures of five MMP-13-ligand complexes are used to build the multiple structure-based pharmacophore model of MMP-13 inhibitors. The reliability of pharmacophore model is validated using a decoy set. The pharmacophore model contains four chemical features: two hydrogen bond acceptor(HBA), one hydrophobic(HY) feature, and one ring aromatic(RA) feature. Particularly, the HY feature is found to orient the MMP-13 inhibitors deep into the S1’ pocket of MMP-13 to produce selective inhibition. By carrying out the screening of pharmacophore model and subsequent molecular docking, the four non-zinc-chelating selective MMP-13 inhibitors of natural products(NP-015973, NP-000814, STOCK1 N-24933, and STOCK1 N-69443) are identified. It is found that the binding modes of MMP-13 with our screened four natural products are very similar to the reported experimental binding mode of MMP-13 with the most active inhibitor(GG12003, IC50: 0.67 n M), and each of them involves the interactions of a ligand with the three amino acid residues Thr226, Lys119, and His201 of MMP-13 receptor. This shows that our modeling results are in good agreement with the relevant experimental results, which strongly supports our screened MMP-13 inhibitors of natural products. These screened natural products may be used as the lead compounds of MMP-13 inhibitors in the future studies of structural modifications.

关键词： matrix metalloproteinase-13 non-zinc-chelating inhibitor of MMP-13 pharmacophore model molecular docking screening

Three-dimensional path planning for unmanned aerial vehicle based on interfered fluid dynamical system

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Chinese Journal of Aeronautics 2015年第1期28卷 229-239页

作者： Wang Honglun Lyu Wentao yao peng Liang Xiao Liu Chang Science and Technology on Aircraft Control Laboratory Beihang University School of Automation Science and Electrical Engineering Beihang University The 28th Research Institute of China Electronics Technology Group Corporation School of Automation Shengyang Aerospace University

This paper proposes a method for planning the three-dimensional path for low-flying unmanned aerial vehicle（UAV） in complex terrain based on interfered fluid dynamical system（IFDS） and the theory of obstacle avoidance by the flowing stream. With no requirement of solutions to fluid equations under complex boundary conditions, the proposed method is suitable for situations with complex terrain and different shapes of obstacles. Firstly, by transforming the mountains, radar and anti-aircraft fire in complex terrain into cylindrical, conical, spherical, parallelepiped obstacles and their combinations, the 3D low-flying path planning problem is turned into solving streamlines for obstacle avoidance by fluid flow. Secondly, on the basis of a unified mathematical expression of typical obstacle shapes including sphere, cylinder, cone and parallelepiped, the modulation matrix for interfered fluid dynamical system is constructed and 3D streamlines around a single obstacle are obtained. Solutions to streamlines with multiple obstacles are then derived using weighted average of the velocity field. Thirdly, extra control force method and virtual obstacle method are proposed to deal with the stagnation point and the case of obstacles＇ overlapping respectively. Finally, taking path length and flight height as sub-goals, genetic algorithm（GA） is used to obtain optimal 3D path under the maneuverability constraints of the UAV. Simulation results show that the environmental modeling is simple and the path is smooth and suitable for UAV. Theoretical proof is also presented to show that the proposed method has no effect on the characteristics of fluid avoiding obstacles.

关键词： obstacles terrain dynamical avoidance unmanned constraints overlapping unified flying spherical

Self-healing Hydrogelsand Underlying Reversible Intermolecular Interactions

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Chinese Journal of Polymer Science 2021年第10期39卷 1246-1261,I0005页

作者： Meng Wu Qiong-yao peng Lin-Bo Han Hong-Bo Zeng Department of Chemical&Materials Engineering University of AlbertaEdmontonAlberta T6G 1H9Canada College of Health Science and Environmental Engineering Shenzhen Technology UniversityShenzhen 518118China

Self-healing hydrogels have attracted growing attention over the past decade due to their biomimetic structure,biocompatibility,as well as enhanced lifespan and reliability,thereby have been widely used in various biomedical,electrical and environmental engineering *** feature article has reviewed our recent progress in self-healing hydrogels derived from mussel-inspired interactions,multiple hydrogen-bonding functional groups such as 2-ureido-4[1H]-pyrimidinohe(UPy),dynamic covalent bonds(eg,Schiff base reactions and boronic ester bonds).The underlying molecular basics of these interactions,hydrogel preparation principles,and corresponding performances and applications are *** underlying reversible intermolecular interaction mechanisms in these hydrogels were investigated using nanomechanical techniques such as surface forces apparatus(SFA)and atomic force microscopy(AFM),providing fundamental insights into the self-healing mechanisms of the *** remaining challenging issues and perspectives in this rapidly developing research area are also discussed.

关键词： Self-healing hydrogels Mussel-inspired Interaction Multiple hydrogen-bonding Dynamic covalent bonds Intermolecular forces