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Simulation of multi-axis grinding considering runout based on envelope theory

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Chinese Journal of Aeronautics 2020年第12期33卷 3526-3534页

作者： yan jiang Qiang GUO School of Mechanical&Power Engineering Henan Polytechnic UniversityJiaozuo 454150China

As one of the most important methods for machining process with high accuracy,ultra-precision grinding is widely used in fields such as aerospace,automotive and mold,***,it is common that wheel and spindle axis do not coincide with each other due to wheel settings,machining errors and so *** could result in the generation of wheel runout,which may reduce the machining surface's *** this paper,combining this phenomenon,an analytic algorithm method for the multi-axis grinding process is introduced according to the envelope *** that,the accuracy of this method is *** experiments are carried out on a 5-axis machining *** artificial runout is set up and calculated utilizing the least square ***,using the presented method,two examples with and without runout are introduced to illustrate the validation of the proposed *** error due to the runout effect is also analyzed.

关键词： Analytic algorithm Complex surface Envelope theory Multi-axis grinding Wheel runout

Soluble Two-dimensional Supramolecular Organic Frameworks(SOFs):An Emerging Class of 2D Supramolecular Polymers with Internal Longrange Orders

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Chinese Journal of Polymer Science 2019年第1期37卷 1-10页

作者： Shu-yan jiang Xin Zhao CAS Key Laboratory of Synthetic and Self-assembly Chemistry for Organic Functional Molecules Center for Excellence in Molecular Synthesis Shanghai Institute of Organic Chemistry Chinese Academy of Sciences

Two-dimensional(2D) materials have been demonstrated to exhibit unique properties originating from its 2D nature. In recent years, the construction of 2D materials has become a topic of great interest. This article summarizes the recent advance of 2D supramolecular organic frameworks(SOFs) which are homogeneously constructed in solution phase through self-assembly of rationally designed building blocks. These 2D SOFs are soluble and still maintain stable network structures in solutions, which exhibit uniqueness not only in structures but also in properties. In this concise review, the SOFs-related background is briefly introduced firstly, followed by outlining the research progress of soluble 2D SOFs from the perspective of monomer design, assembly, and structural *** article ends with a personal outlook on the future development of this new class of supramolecular polymers.

关键词： Supramolecular organic frameworks(SOFs) Self-assembly Two-dimensional Supramolecular polymers

Mean-Square Output Consensus of Heterogeneous Multi-Agent Systems with Multiplicative Noises in Dynamics and Measurements

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Journal of Systems Science & Complexity 2023年第6期36卷 2364-2381页

作者： LIN Bo LUO Shixian jiang yan Guangxi Key Laboratory of Disaster Prevention and Engineering Safety Guangxi UniversityNanning530004China School of Electrical Engineering Guangxi UniversityNanning530004China

This paper studies the output consensus problem of heterogeneous linear stochastic multiagent systems with multiplicative noises in system parameters and measurements,where the system noise in each agent is allowed to be *** employing stochastic output regulation theory and the stochastic Lyapunov function approach,a composite controller embedded with stochastic output regulator equations(SOREs)and a stochastic dynamic compensator is designed to achieve the meansquare output consensus of the multi-agent *** implement the consensus algorithm,a sufficient condition for feasible solutions of the SOREs is first established in terms of Lyapunov and Selvester *** the time-varying SOREs are approximated by the Euler-Maruyama method combined with an a-posteriori partial estimation of the increments of the Brownian motion.A numerical example illustrates the theoretical results.

关键词： Heterogeneous multi-agent systems multiplicative noise output consensus stochastic output regulation

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基于预测误差法的无人机安全控制器设计

电光与控制 2025年第1期32卷 90-94页

作者：姜燕王道波柏婷婷张莹南京航空航天大学自动化学院南京210000

具备安全性的无人机控制器是保障无人机作战完整性的重要因素之一,该控制器能够在安全的界限范围内控制无人机的飞行性能。针对无人机的安全控制器的设计问题,首先,对无人机的闭环控制系统进行分析,并采用非参数预测误差估计的方法对闭... 详细信息

具备安全性的无人机控制器是保障无人机作战完整性的重要因素之一,该控制器能够在安全的界限范围内控制无人机的飞行性能。针对无人机的安全控制器的设计问题,首先,对无人机的闭环控制系统进行分析,并采用非参数预测误差估计的方法对闭环控制系统中的执行机构模块进行辨识,以证明辨识得到的模型与实际模型无偏;其次,阐明了无人机安全性的含义,并在闭环控制系统的辨识模型的基础上,对无人机的安全控制器进行了设计;最后,以无人机飞行姿态角中的俯仰通道为例,对安全控制器性能进行了仿真验证。实验结果证明了无人机安全控制器的有效性,能够将无人机的飞行性能控制在安全范围内,为飞行安全提供保障。

关键词：无人机闭环控制系统安全性控制器预测误差估计

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Determining the moment of inertia of triaxial Mars with updated global gravity models

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Earth and Planetary Physics 2023年第6期7卷 615-619页

作者： ChangYi Xu yan jiang Institute of Geology and Geophysics Chinese Academy of SciencesBeijing 100029China

The principal moments of inertia(PMIs)with the principal axes are usually taken as the dynamic figure parameters of Mars;they can be deduced from satellite-observed degree-two gravitational potentials in recent global gravity models and from the dynamic ellipticities resulting from precession *** PMIs are natural and significant for the geodetic,geophysical,and geodynamic problems of Mars,which are functions of internal density *** this study,a closed and concise formula for determining the PMIs of the entire planet and its core was developed based on the second invariants of gravity and a multipole *** deduced the polar oblateness J^(2)and the equatorial ellipticity J_(22)of Mars to be 1.9566×10^(−3)and 6.3106×10^(−5),*** preferred principal moments of inertia of Mars are A=2.66589×1036 kg·m^(2),B=2.66775×10^(36)kg·m^(2),and C=2.68125×10^(36)kg·m^(2).These values indicate that Mar is slightly *** equatorial principal moment of inertia of the Martian core is 1.46008×10^(35)kg·m^(2),accounting for~5.47%of the planet’s PMI;this result is critical for investigating the density and size of the core of Mars,and the planet’s free core nutation.

关键词： Mars principal moment of inertia dynamic ellipticity Chandler wobble core density and size

Nonlinear balance constraints in 3DVAR data assimilation

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Science China Earth Sciences 2006年第3期49卷 331-336页

作者： ZHU jiang yan Changxiang International Center for Climate and Environment Sciences Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China International Center for Climate and Environment Sciences Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China

In many applications of 3DVAR, the balance constraints can be considered via two main approaches: weak constraint method which adds penalty terms to the cost function; and proper defi- nition of the background error covariance matrix with non-zero cross-correlation sub-matrices. The weak constraint approach requires determining the weighting matrices of the penalty terms. The background error covariance approach does not require determining those additional weighting ma- trices. However, it is only applicable to those linear or linearized balance constraints. A novel ap- proach is proposed based on the background error covariance approach by generalizing the so-called Derber-Bouttier formulation. An assimilation experiment of estimating temperature and salinity from the sea surface dynamic height observation is given to illustrate the proposed treatments of nonlinear balance constraints.

关键词： 3DVAR, linear balance constraint, nonlinear balance constraint, background error covariance matrix, sea surface dynamic height.

Novel method for separation and screening of lubricant-degrading microorganisms and bacterial biodegradation

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Chinese Journal of Chemical Engineering 2016年第3期24卷 353-359页

作者： yan jiang Hui Qi Xianming Zhang Engineering Research Centre for Waste Oil Recovery Technology and Equipment Ministry EducationChongqing Technology and Business University College of Foreign Languages Chongqing Technology and Business University

With the rapid increase of lubricant consumption, oil contamination becomes more serious. Biotreatment is an important method to remove oil contamination with some advantages. In this study, acclimatized oil- contaminated soil and used lubricating oil were sampled to isolate lubricant-degrading strains by several methods. 51 isolates were obtained and 24-well plates were employed to assess bacterial potential in high- throughput screening. The method was noted for the prominence of oil-water two-phase system with saving chemicals, shortening cycles and lessening workloads. In order to decrease inaccuracy, subculture and resting cells were inoculated into mineral salt medium with 200 μ1 oil in well plates for the cultivation at 37 ℃ for 5 and 7 days, and the biodegradation potential was characterized by the changes of oil film and cell density. With appropriate evaluation by shaking flask tests, 5 isolates were retained for their potentials with the maxi- mum biodegradation from 1500 to 2200 mg· L-1 and identified as Acidovorax dtrulli, Pseudomonos balearica, Adnetobacterjohnsonii （two isolates with different biodegradation potentials） and Addovorax avenae using 16S rRNA sequencing analysis. Also, lipase activity was determined using indicator titration and p-nitrophenyl palmitate （p-NPP） methods. The results indicated that only p-NPP was successful to test lipase activity with the range of 1.93-6.29 mg· L-1 Although these five strains could degrade 1000 mg· L-1 lubricating oil in 158-168 h, there existed distinct difference in enzyme activity, which demonstrates that lipase activity could not be used as the criterion to evaluate microbial biodegradation potential for petroleum hydrocarbons.

关键词： Lubricant Degradation Separation 24-well plate Enzyme

Mechanism for the multi-stage precipitation of Fe-Ni based alloy

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Journal of Materials Science & Technology 2019年第11期35卷 2582-2590页

作者： yan jiang Qiang Zuo Feng Liu State Key Laboratory of Solidification Processing Northwestern Polytechnical University

This work lays great emphasis on the distribution evolution of sigma(σ)phase in Fe-Ni based N08028 alloy during aging process,the result of which could provide new insights into phase change and precipitation *** is found that theσphase,in any case,tends to separate out with a granular shape at grain boundaries(GBs)primarily,and with the increment of time,it is obliged to precipitate in grain interiors(GIs)with a lamellar *** mechanisms for the evolving volume fraction and morphology ofσphase are discussed,and a model appropriate for the multi-stage behavior transforming from intergranular to intragranular precipitation is derived,as well as revealing the thermodynamics and transformation kinetics corresponding to this *** results reveal that the occurrence of multi-stage precipitation is correlated with the redistribution of solute atoms and with the difference in coupling effect of thermodynamic driving force and kinetic activation energy between the intergranular and intragranular precipitation.

关键词： Precipitation Intergranular precipitation Intragranular precipitation Thermodynamics Transformation kinetics

MODEL ANALYSIS AND PARAMETER EXTRACTION FOR MOS CAPACITOR INCLUDING QUANTUM MECHANICAL EFFECTS

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Journal of Computational Mathematics 2006年第3期24卷 401-411页

作者： Hai-yan jiang Ping-wen Zhang LMAM CCSE and School of Mathematical Sciences.Peking University Beijing 100871 China

The high frequency CV curves of MOS capacitor have been studied. It is shown that semiclassical model is a good approximation to quantum model and approaches to classical model when the oxide layer is thick. This conclusion provides us an efficient （semiclassical） model including quantum mechanical effects to do parameter extraction for ultrathin oxide device. Here the effective extracting strategy is designed and numerical experiments demonstrate the validity of the strategy.

关键词： Poisson Equation SchrSdinger Equation MOS Capacitor Quantum Effect,Sensitivity Parameter Extraction.