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ADAPTIVE PRACTICAL OUTPUT MANEUVERING CONTROL FOR A CLASS OF NONLINEAR SYSTEMS

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Journal of Systems Science & Complexity 2007年第1期20卷 75-84页

作者： Chunling WEI Yuqiang wu Shumin FEI Instituteof Automation Southeast University Nanjing 210096 China Institute of Automation Qufu Normal University Qufu 273165 China Institute of Automation Southeast University Nanjing 210096 China.

This paper deals with the adaptive practical output maneuvering control problems for a class of nonlinear systems with uncontrollable unstable linearization. The objective is to design a smooth adaptive maneuvering controller to solve the geometric and dynamic tasks with an arbitrary small steady tracking error. The method of adding a power integrator and the robust recursive design technique are employed to force the system output to track a desired path and make the tracking speed to follow a desired speed along the path. An example is considered and simulation results are given. The proposed design procedure can be illustrated by the use of this example.

关键词： Adaptive output maneuvering control adding a power integrator method practical output tracking recursive design technique.

Horizontal crustal movement in China fitted by adaptive collocation with embedded Euler vector

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Science China Earth Sciences 2011年第12期54卷 1822-1829页

作者： YANG YuanXi ZENG AnMin wu FuMei Xi＇an Research Institute of Surveying and Mapping Xi＇an 710054 China Zhengzhou Institute of Surveying and Mapping Zhengzhou 450052 China

The crustal movements of the Chinese mainland include an average regional movement trend of the mainland and complex local deformations. Thus, both trends in the crustal movement of the mainland and local distortions should be simultaneously taken into consideration in crustal movement estimations. A combined collocation model based on Euler vector (taken as trend parameters) and local distortions (taken as signals) is proposed in this paper. We assume that prior covariance matrices between signals and observations should be consistent with their uncertainties. Otherwise, the station movement estimates provided by the collocation will be distorted. Thus, an adaptive collocation estimator based on simplified Helmert variance components is applied. This means that the contributions of signals and observations to estimates of crustal movements are balanced and reasonable, and consistent covariance matrices of the signals and observations are achieved through the adjustment of the adaptive factor. The calculation of actual horizontal movements of the Chinese crust shows that the estimates of horizontal crustal movement velocities are made more accurate by the adaptive collocation model.

关键词： adaptive collocation variance component estimation velocity field crustal deformation Euler vector

A New Synthetic Method of （Z）-4-Aryl-but-2-en-l-ols via Suzuki-Miyaura Cross-Coupling Reaction of 4-Substituted 1,2-Oxaborol-2（5H）-ols with Benzyl Bromides

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Chinese Journal of Chemistry 2012年第12期30卷 2798-2804页

作者： Yu Tao wu Xinyan Yang Jun Key Laboratory for Advanced Materials and Institute of Fine Chemicals East China University of Science and Technology 130 Meilong Road Shanghai 200237 China Shanghai Institute of Organic Chemistry Chinese Academy of Science 345 Lingling Road Shanghai 200032 China

Z and E configuration 4-aryl-but-2-en-1-ols were isolated from several terrestrial plants, and （Z）-4-aryl-but-2- en-l-ols were found to have choleretic activity. Strategies have been reported to synthesize （E）-4-aryl-but-2-en-l- ols with high selectivity. However, there is no method to obtain （Z）-4-aryl-but-2-en-1-ols with high selectivity now. We developed a Suzuki-Miyaura cross-coupling reaction of 1,2-oxaborol-2（5H）-ols with benzyl bromides to synthesize （Z）-4-aryl-but-2-en-1-ols, the products were obtained in up to 94% isolated yield.

关键词： Suzuki-Miyaura cross-coupling reaction palladium-catalyzed (Z)-but-2-en-l-ols benzyl bromides

Demixing microwave signals using system-on-chip photonic processor

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Light(Science & Applications) 2024年第3期13卷 399-401页

作者： Sheng Gao Chu wu Xing Lin Department of Electronic Engineering Tsinghua University100084 BeijingChina Beijing National Research Center for Information Science and Technology Tsinghua University100084 BeijingChina

The integrated photonic processor,co-packaged with electronic peripherals,is proposed for blind source separation of microwave signals,which separates signal-of-interest from dynamic interference with real-time adapta... 详细信息

关键词： processor microwave mixing

Evolution of misfit dislocation network and tensile properties in Ni-based superalloys:a molecular dynamics simulation

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Science China(Physics,Mechanics & Astronomy) 2012年第3期55卷 419-427页

作者： wu WenPing GUO YaFang WANG YueSheng Department of Engineering Mechanics Wuhan UniversityWuhan 430072China Department of Mechanical Engineering University of WuppertalWuppertal 42097Germany Institute of Engineering Mechanics Beijing Jiaotong UniversityBeijing 100044China

The structural evolution of dislocation network is closely related to y' rafting and tensile properties. In this work, the effects of strain rate and temperature on the structural evolution of interface dislocation network in Ni-based superalloys are studied by molecular dynamics simulations. The correlation between the evolution of dislocation network and tensile properties is also explored. The results indicate that the dislocation network shows different degrees of deformation and damage at various strain rates and temperatures. The ),' rafting depends on the damage structure of dislocation network at various strain rates and tem- peratures. Moreover, the tensile properties of interface in Ni-based superalloys are closely related to the evolution of disloca- tion network and dislocation motion mechanisms.

关键词： Ni-based superalloys tensile properties dislocation network rafting molecular dynamics simulation

Basical characteristics of fluid geologic process of interlayer oxidation zone sandstone-typeuranium deposit

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Science China Earth Sciences 2007年第z2期50卷 185-194页

作者： wu BoLin LIU ChiYang WANG JianQiang State Key Laboratory of Continental Dynamics(Northwest University) Xi'an 710069 China State Key Laboratory of Continental Dynamics(Northwest University) Xi'an 710069 China State Key Laboratory of Continental Dynamics(Northwest University) Xi'an 710069 China

This paper reveals the physicochemical properties such as component, formulation, genesis, tem- perature, pH, Eh, salinity and pressure of all main alteration fluid of interlayer oxidation zone sand- stone-type uranium deposits after studying the geologic process and geochemistry of internal typical sandstone-type uranium deposits such as Shihongtan deposit in the Turpan-Hami basin, 512 deposit in the Yili basin, Dongsheng deposit in the Ordos basin. The composition of fluid can be divided into two parts based on the analysis of inclusion: one can be affirmed as atmospheric water with ordinary temperature epigenesist according to the character of hydrogen and oxygen isotope of inclusion, the other is natural gas containing gaseous hydrocarbon like CH4, and CO2 as well as a little H2S, CO, H2, N2 and so on, it always contains a small quantity of hydrocarbon liquid in petroliferous basins. The fluid property of oxidation alteration zone is always oxidation alkaline, and neutrality or weak acid-weak alkaline and reducibility during the metallizing process, but at secondary reduction or deoxidization zone it becomes strong reduction alkaline. Oxygenic groundwater in the fluid is the activate and mig- ratory medium of uranium element, but the gaseous hydrocarbon like CH4 as well as H2, H2S, CO from natural gas is the important sedimentary reducer of uranium mineral; the transformation of pH,Eh in fluid environment is the main reason for the formation of uranium metallization.

关键词： fluid, interlayer oxidation zone, uranium deposit, inclusion, isotope

Coherent Phase-Coded Pulse Train with Doppler Cascade-Processing for Detection of Aircraft Target in a HF Radar

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Journal of Systems Engineering and Electronics 1999年第3期10卷 50-56页

作者： Shen, Yiying Liu, Yongtan wu, Aiguang Harbin Inst of Technology Harbin China

The effect of range-Doppler coupling caused by aircraft moving at very high speed makes trouble on selection of waveform parameters by using frequency-modulated interrupted continuous wave (FMICW) or frequency-coded pulse (FCP). It also limits the increasing of coherent integration time. In this paper, application of coherent phase-coded pulse train (CPCPT) solves range-Doppler coupling well. Relevant processing of CPCPT consists of three parts: Doppler preprocessing, pulse compression, and Doppler post-processing. The velocity information obtained by Doppler preprocessing is used for better pulse compression and range tracking. Doppler post-processing with range tracking could make longer coherent accumulation for better detection of target and higher velocity resolution. Finally, examples of data simulation are given to demonstrate the achievements mentioned above.

关键词： Computer simulation Doppler effect Frequency modulation Problem solving Waveform analysis

Syntheses, Structures and Luminescent Properties of Two Europium-based Metal-organic Frameworks

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Chinese Journal of Structural Chemistry 2015年第8期34卷 1265-1272页

作者： ZOU Shu-Zhi DU Shao-wu State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of Matter Chinese Academy of Sciences Graduate University of Chinese Academy of Sciences

Two new europium-based metal-organic-frameworks （MOFs）, namely [NMen][Eu（m- BDC）2] （1） and [Eu3（p-BDC）4（ClO4）（H2O）4] （2）, have been synthesized and structurally characte- rized. Single-crystal X-ray diffraction studies reveal that 1 crystallizes in the monoclinic system, space group P21/n with a 2D layer structure, while 2 crystallizes in the orthorhombic system, space group Pccn with a 3D net structure. Both 1 and 2 have strong characteristic Eu（Ⅲ） emissions at visible red region and the quantum yields can reach up to 78.1 and 46.0%, respectively. The high luminescent efficiency may be attributed to the efficient energy transition from the ligands to the Eu（Ⅲ） center.

关键词： synthesis, crystal structure, lanthanide-based MOFs, luminescence

Sulfated peptides and their receptors:Key regulators of plant development and stress adaptation

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Plant Communications 2024年第6期5卷 44-56页

作者： Liming He Liangfan wu Jia Li Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations School of Life SciencesLanzhou UniversityLanzhou 730000China Guangdong Provincial Key Laboratory of Plant Adaptation and Molecular Design School of Life SciencesGuangzhou UniversityGuangzhou 510006China

Four distinct types of sulfated peptides have been identiﬁed in Arabidopsis *** peptides play crucial roles in regulating plant development and stress *** studies have revealed that Xan-thomonas and Meloidogyne can secrete plant-like sulfated peptides,exploiting the plant sulfated peptide signaling pathway to suppress plant *** the past three decades,receptors for these four types of sulfated peptides have been identiﬁed,all of which belong to the leucine-rich repeat receptor-like protein kinase subfamily.A number of regulatory proteins have been demonstrated to play important roles in their corresponding signal transduction *** this review,we comprehensively summarize the discov-eries of sulfated peptides and their receptors,mainly in Arabidopsis *** also discuss their known biological functions in plant development and stress ***,we put forward a number of ques-tions for reference in future studies.

关键词： peptide hormone sulfated peptide receptor-like protein kinase plant development stress adaptation