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Design of Adaptive Robust Guaranteed Cost Controller for Wind Power Generator

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International Journal of Automation and computing 2013年第2期10卷 111-117页

作者： zhong-Qiang Wu jian-Ping Xie Key Laboratory of Industrial Computer Control Engineering Yanshan University

According to the increasing requirement of the wind energy utilization and the dynamic stability in the variable speed variable pitch wind power generation system, a linear parameter vary.ng （LPV） system model is established and a new adaptive robust guaranteed cost controller （AGCC） is proposed in this paper. First, the uncertain parameters of the system are estimated by using the adaptive method, then the estimated uncertain parameters and robust guaranteed cost control method are used to design a state feedback controller. The controller s feedback gain is obtained by solving a set of linear matrix inequality （LMI） constraints, such that the controller can meet a quadratic performance evaluation criterion. The simulation results show that we can realize the goal of maximum wind energy capture in low wind speed by the optimal torque control and constant power control in high wind speed by variable pitch control with good dynamic characteristics, robustness and the ability of suppressing disturbance.

关键词： Wind power generator linear parameters vary.ng (LPV) system adaptive control robust control guaranteed cost control

Two new Bisabolane Sesquiterpenes from Ligularia Thyrsoidea

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Chemical Research in Chinese Universities 1999年第1期15卷 69-71页

作者： LIAO jian-chun y.nG Li JIA zhong-jian Department of Chemistry National Laboratory of Applied ChemistryLanzhou UniversityLanzhou730000

ＩｎＣｈｉｎａ，ｍｏｒｅｔｈａｎ２０Ｌｉｇｕｌａｒｉａｓｐｅｃｉｅｓ（Ｃｏｍｐｏｓｉｔａｅ）ｈａｖｅｂｅｅｎｕｓｅｄｆｏｒｆｏｌｋｍｅｄｉｃｉｎｅｓｗｉｔｈａｎｔｉｂｉｏｔｉｃ，ａｎｔｉｐｈｌｏｇｉｓｔｉｃａｎｄａｎ... 详细信息

ＩｎＣｈｉｎａ，ｍｏｒｅｔｈａｎ２０Ｌｉｇｕｌａｒｉａｓｐｅｃｉｅｓ（Ｃｏｍｐｏｓｉｔａｅ）ｈａｖｅｂｅｅｎｕｓｅｄｆｏｒｆｏｌｋｍｅｄｉｃｉｎｅｓｗｉｔｈａｎｔｉｂｉｏｔｉｃ，ａｎｔｉｐｈｌｏｇｉｓｔｉｃａｎｄａｎｔｉｔｕｍｏｒａｃｔｉｖｉｔｉｅｓ...

关键词： Ligularia thyrsoidea Bisabolane Sesquiterpene 2D nMR

In situ Raman spectroscopy reveals the mechanism of titanium substitution in P2–na_(2/3)ni_(1/3)Mn_(2/3)O_(2): Cathode materials for sodium batteries

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Journal of Energy Chemistry 2021年第2期30卷 323-328,I0011页

作者： Xiao-Bin zhong Chao He Fan Gao zhong-Qun Tian jian-Feng Li School of Mechanical and Power Engineering North University of ChinaTaiyuan 030051ShanxiChina State Key Laboratory of Physical Chemistry of Solid Surfaces College of Chemistry and Chemical EngineeringXiamen UniversityXiamen 361005FujianChina

Layered P2–na_(2/3)ni_(1/3)Mn_(2/3)O_2 is a promising cathode material. It exhibits a high capacity and suitable operating voltage and undergoes a phase transition from P2 to O2 during charge/*** have used Ti substitution to improve the cathode, yet the chemical principles that underpin elemental substitution and functional improvement remain unclear. To clarify these principles, we used in situ Raman spectroscopy to monitor chemical changes in P2–na2/3 ni1/3 Mn1/3 Ti1/3 O2 and P2–na_(2/3)ni_(1/3)Mn_(2/3)O_2 during charge/discharge. Based on the change in the A_(1g) and E_g peaks during charge/discharge, we concluded that Ti substitution compressed the transition metal layer and expanded the planar oxygen layer in the unit cell. Titanium stabilized the P2 phase structure, which improved the cycling stability of P2–nanMT. Our results provide clear theoretical support for future research on modify.ng electrodes by elemental substitution.

关键词： In situ Raman spectroscopy P2–na_(2/3)ni_(1/3)Mn_(2/3)O_(2) Titanium substitution

Production scheduling problems of steelmaking-continuous casting process in dynamic production environment

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Journal of Iron and Steel Research International 2017年第6期24卷 586-594页

作者： zhong Zheng jian-yu Long Xiao-qiang Gao College of Materials Science and Engineering Chongqing University Chongqing 400045 China College of Economics and Business Administration Chongqing University Chongqing 400044 China

A concept of production scenario for the steelmaking continuous casting production process and the mathe- matical description of such concept were proposed. The production scenario was described with the varia- tion of the equipment status and the production material properties based on the executing production schedule. Then, the dynamic characteristics of the production process could be described with the evolu tion process of production scenario. Through analyzing the influence of the dynamic production scenario on production scheduling, three key points about the scheduling problems were identified： the problem for integrating the schedules of different batches that is non-neglected when making a schedule, the problem for matching the material flow with the schedule that should be solved when implementing a schedule, and the problem for eliminating the deviations between the initial schedule and implemented schedule that should be solved when rescheduling in a disturbed environment. Finally, a set of experiments were con- ducted, and the results demonstrated that making the production schedule and solving the rescheduling problem for steelmaking continuous casting process with addressing the above three problems improve the adaptability of the schedule in dynamic environment.

关键词： SchedulingReschedulingSteelmakingContinuous castingDisturbanceProduction scenario

Sensitivity Experiments on the Poleward Shift of Tropical Cyclones over the Western north Pacific under Warming Ocean Conditions

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Journal of Meteorological Research 2018年第4期32卷 560-570页

作者： yixuan SHEn yuan SUn zhong zhong Kefeng LIU jian SHI College of Meteorology and Oceanography National University of Defense Technology

Recent studies found that in the context of global warming, the observed tropical cyclones （TCs） exhibit signific-ant poleward migration trend in terms of the mean latitude where TCs reach their lifetime-maximum intensity in the western north Pacific （WnP）. This poleward migration of TC tracks can be attributed to not only anthropogenic for-cing （e.g., continuous increase of sea surface temperature （SST））, but also impacts of other factors （e.g., natural vari- ability）. In the present study, to eliminate the impacts of other factors and thus focus on the impact of unvaried SST on climatological WnP TC tracks, the mesoscale Weather Research and Forecasting （WRF） model is used to con- duct a suite of idealized sensitivity experiments with increased SST. Comparisons among the results of these experi- ments show the possible changes in climatological TC track, TC track density, and types of TC track in the context of SST increase. The results demonstrate that under the warmer SST conditions, the climatological mean TC track sys-tematically shifts poleward significantly in the WnP, which is consistent with the previous studies. Meanwhile, the ocean warming also leads to the decreased （increased） destructive potential of TCs in low （middle） latitudes, and thus northward migration of the region where TCs have the largest impact. Further results imply the possibility that under the ocean warming, the percentage of TCs with westward/northwestward tracks decreases/increases distinctly.

关键词： tropical cyclone ocean warming poleward shift numerical experiment

Pattern of polycyclic aromatic hydrocarbons (PAHs) pollution in communication air of Hangzhou, China

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Journal of Environmental Sciences 2002年第2期14卷 145-150页

作者： WAnG Jing ZHU Li-zhong LIU y.ng-jian Department of Environmental Science Zhejiang UniversityHangzhou 310028China.

nine PAHs were surveyed in communication air of Hangzhou. The results indicated that the PAHs pollution is very serious and the total sum of 9 PAHs, on the average are 3.39-13.82 μg/m 3. The PAHs signatures for all streets are similar to each other. Multivariate statistical techniques were used to investigate source apportionment for PAHs. A factor analysis/multiple regression model was successfully applied to the study. The most important three PAHs sources in communication air are diesel emission, gasoline engine emission, coal burning accounting for 61.1±6.4%, 19.9±8.3%, 10.8±10.8% of total PAHs, respectively. The relationship for three source tracers and total PAHs is: [PAHs] =1.471(±0.155)[Phen] + 2.538 (±2.522)[1-Mepy]+2.254 (±0.943)[Chry]+1.022 (±1.767).

关键词： PAHs air source apportionment city communication

Research on new software compensation method of static and quasi-static errors for precision motion controller

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第12期8卷 1938-1943页

作者： REn Kun FU jian-zhong CHEn Zi-chen Department of Mechanical Engineering Zhejiang University Hangzhou 310027 China

To reduce mechanical vibrations induced by big errors compensation, a new software compensation method based on an improved digital differential analyzer (DDA) interpolator for static and quasi-static errors of machine tools is proposed. Based on principle of traditional DDA interpolator, a DDA interpolator is divided into command generator and command analyzer. There are three types of errors, considering the difference of positions between compensation points and interpolation segments. According to the classification, errors are distributed evenly in data processing and compensated to certain interpolation segments in machining. On-line implementation results show that the proposed approach greatly improves positioning accuracy of computer numerical control (CnC) machine tools.

关键词： Static and quasi-static errors Positioning and machining accuracy Digital differential analyzer (DDA) interoolator

Selective reduction of carbon dioxide into amorphous carbon over activated natural magnetite

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International Journal of Minerals,Metallurgy and Materials 2021年第2期28卷 231-237页

作者： zhong-qing Liu jian Zheng yi Wang Xu Liu School of Chemical Engineering Sichuan UniversityChengdu 610065China

natural magnetite formed by the isomorphism substitutions of transition metals,including Fe,Ti,Co,etc.,was activated by mechanical grinding followed by H2 *** temperature-programmed reduction of hydrogen(H2-TPR)and temperature-programmed surface reaction of carbon dioxide(CO2-TPSR)were carried out to investigate the processes of oxygen loss and CO2 *** samples were characterized by X-ray diffraction(XRD),field emission scanning electron microscopy(FE-SEM),and energy-dispersive X-ray spectroscopy(EDS).The results showed that the stability of spinel phases and oxygen-deficient degree significantly increased after natural magnetite was mechanically milled and reduced in H2 ***,the activity and selectivity of CO2 reduction into carbon were *** deposited carbon on the activated natural magnetite was confirmed as *** amount of carbon after CO2 reduction at 300°C for 90 min over the activated natural magnetite was 2.87wt%higher than that over the natural magnetite.

关键词： carbon dioxide reduction natural magnetite isomorphism substitutions grind activation oxygen-deficient degree amorphous carbon

Size-effect on ni electrocatalyst:The case of electrochemical benzyl alcohol oxidation

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nano Research 2023年第1期16卷 202-208页

作者： jian zhong y.ngli Shen Pei Zhu Shuang yao Changhua An Tianjin Key Laboratory of Organic Solar Cells and Photochemical Conversion School of Chemistry and Chemical EngineeringTianjin University of TechnologyTianjin 300384China Tianjin Key Laboratory of Advanced Functional Porous Materials Institute for New Energy Materials&Low-Carbon TechnologiesSchool of Materials Science and EngineeringTianjin University of TechnologyTianjin 300384China

The nanoparticles(nPs)of ni with different sizes endows its distinctive physical and chemical properties,which represents a typical strategy for the development of high-performance ***,the size effect of metallic ni-nPs on electrocatalytic performance remains ***,the ni-nPs with different sizes supported on nitrogen doped carbon(nC)has been synthesized by controlling the pyrolysis temperature,leading to the synthesis of ni@nC-500(8.3 nm),ni@nC-280(1.9 nm)and ni@nC-200(1.0 nm).The electrooxidation of benzyl alcohol(BA)over these nanocatalysts shows the yield of benzoic acid was 99%,82%,55%on ni@nC-280,ni@nC-200 and ni@nC-500,*** experimental and theoretical simulation demonstrate that the difference in the adsorption strength of reactant molecules by.ni-nPs is responsible for their different performance,where the ni@nC-280 exhibits an optimal adsorption configuration between ni@nC-280 electrode and *** work provides a new angle for designing and synthesizing efficient electrocatalysts,which may be extended to the exploration of various promising electrocatalytic systems.

关键词： size effect electro-oxidation ni nanoparticles benzyl alcohol