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Study of trajectory optimization using terminal-node adaptive-altered spline algorithm

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Journal of Systems Engineering and Electronics 2009年第3期20卷 551-557页

作者： Xia Qunli guo tao Qi Zaikang School of Aerospace Science and Engineering Beijing Inst. of Technology Beijing 100081 P. R. China

The advantage of using a spline function to evaluate the trajectory parameters optimization is discussed. A new method that using adaptive varied terminal-node spline interpolation for solving trajectory optimization is proposed. And it is validated in optimizing the trajectory of guided bombs and extended range guided munitions （ERGM）. The solutions are approximate to the real optimization results. The advantage of this arithmetic is that it can be used to solve the trajectory optimization with complex models. Thus, it is helpful for solving the practical engineering optimization problem.

关键词： trajectory optimization optimization control parameter optimization spline interpolation

Particle filter based stochastic interference cancellation for frequency-selective MIMO channel equalization

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Journal of Systems Engineering and Electronics 2007年第3期18卷 476-483页

作者： Yang tao Hu Bo guo Xinyue Dept. of Electronics Engineering Fudan Univ. Shanghai 200433 P. R. China

To mitigate the effects of the previous symbol decision errors of a decision-feedback （DF） equalizer on the current decision, a particle filter （PF） based DF equalizer for frequency selective multiple-input-multiple-output （MIMO） channel is proposed. On the basis of the analyses of DF equalization for the MIMO wireless system, it is found that a stochastic interference cancellation （IC） scheme can be employed to prevent the error propagation in a severe space-time interference scenario. This is because the random rather than the deterministic scheme can reduce the probability of an error decision even if an error decision occurs. Besides, the signal-to-interference-plus-noise ratio （SINR） based IC order, which is obtained via pilot, can guarantee the optimality of the cancellation. The bit error rate （BER） performance of the proposed scheme is verified through simulation experiments under different multipath interference environment.

关键词： multiple-input-multiple-output particle filter pilot decision-feedback interference cancellation.

Effect of incubation temperature and wet-dry cycle on the availabilities of Cd,Pb and Zn in soil

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Journal of Environmental Sciences 2006年第6期18卷 1119-1123页

作者： SI Ji-tao TIAN Bao-guo WANG Hong-tao Department of Environmental Science and Engineering Tsinghua University Beijing 100084 China

The effect of incubation temperature and wet-dry cycle on the availabilities of Cd, Pb and Zn was studied. Three soils with pH ranging from 3.8 to 7.3, organic carbon （OC） from 0.7% to 2.4%, and clay from 12.3% to 35.6% were selected. Soils were spiked with reagent grade Cd（NO3）2, Pb（NO3）2, and Zn（NO3）2 at concentrations of 30 mg Cd/kg soil, 300 mg Zn/kg soil and 2000 mg Pb/kg soil. The soils were incubated at 35, 60, 105℃, respectively and went through four wet-dry cycles. Metal availability in soils was estimated by soil extraction with 0.1 mol/L Ca（NO3）2. According to this study, the effect of the spiking temperature on the metal availabilities was different among the metals, soils and wet-dry cycles. Mostly, 35 ~C was the first recommended spiking temperature for Cd and Pb while no spiking temperature was obviously better than others for Zn. Three wet-dry cycles was recommended regardless of the type of metals and incubation temperature.

关键词： availability wet-dry cycle cadmium (Cd) zinc (Zn) lead (Pb)

Creating future crops:a revolution for sustainable agriculture

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Journal of Genetics and Genomics 2021年第2期48卷 97-101页

作者： tao guo Hong-Xuan Lin National Key Laboratory of Plant Molecular Genetics CAS Centre for Excellence in Molecular Plant SciencesShanghai Institute of Plant Physiology and EcologyChinese Academy of SciencesShanghai 200032China University of the Chinese Academy of Sciences Beijing 100049China School of Life Science and Technology Shanghai Tech UniversityShanghai 201210China

Despite the remarkable increase in food supply over the past halfcentury,global food security is facing unprecedented challenges as a result of a blooming human population,a shortage of arable land,and the significant threat posed by climate change(Bailey-Serres et al.,2019;Tian et al.,2020).Current crop production strategies are insufficient to nourish the world *** ensure food security and the development of sustainable abuilding to explore emerging strategies and design novel crops with high productivity and efficiency,which are also more resilient to climate variability and natural disasters.

关键词： crops sustainable spite

All-Solid-State Near-Infrared and Blue Femtosecond Laser System

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Chinese Physics Letters 2002年第2期19卷 203-204页

作者： Bai Jin-tao, Chen guo-Fu Institute of Photonics & Photo-technology Northwest University Provincial Key Laboratory of Photoelectronic Technology Northwest University State Key Laboratory of Transient Optics and Technology Xi"an Institute of Optics and Precision Mechanics Chi

We investigate an all-solid-state continuous wave (cw) green (532 nm), femtosecond near-infrared (823.1 nm) and blue (402 nm) laser system which is pumped by a diode-laser-pumped intracavity frequency-doubled and all-self-structuring cw Nd:YVO4/KTP 532 nm green laser. The cavity parameters of the Nd:YVO4/KTP laser have been optimized and the maximum 5.6 W TEM00 green laser is obtained at a 22 W pump power with an optical-optical conversion efficiency of 25.5%. A Ti:Sapphire laser and nonlinear second-harmonic generation by a crystal BBO is used to obtain different wavelengths. A femtosecond laser with an average output power of 300 mW at 823.1 nm and 73 mW at 402 nm is obtained when the green pump power is 2.5 W. The spectral full width at half maximum are 32.3 nm and 5.1 nm, which can sustain the pulses of 22 fs and 33.3 fs, respectively

关键词： Femtosecond lasers

Pentavalent Symmetric Graphs of Order 16p

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Acta Mathematicae Applicatae Sinica 2017年第1期33卷 115-124页

作者： Song-tao guo Hai-long HOU Jiang-tao SHI School of Mathematics and Statistics Henan University of Science and Technology School of Mathematics and Information Science Yantai University

A graph is said to be symmetric if its automorphism group acts transitively on its arcs. In this paper, a complete classification of connected pentavalent symmetric graphs of order 16p is given for each prime p. It follows from this result that a connected pentavalent symmetric graph of order 16p exists if and only if p = 2 or 31, and that up to isomorphism, there are three such graphs.

关键词： symmetric graph s-transitive graph s-regular graph

Working fluids of a low-temperature geothermally-powered Rankine cycle for combined power and heat generation system

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Science China(Technological Sciences) 2010年第11期53卷 3072-3078页

作者： guo tao WANG HuaiXin ZHANG ShengJun Department of Thermal Energy and Refrigeration Engineering Tianjin UniversityTianjin 300072China

A novel combined power and heat generation system was investigated in this study. This system consists of a low-temperature geothermally-powered organic Rankine cycle (ORC) subsystem, an intermediate heat exchanger and a commercial R134a-based heat pump subsystem. The advantages of the novel combined power and heat generation system are free of using additional cooling water circling system for the power generation subsystem as well as maximizing the use of thermal energy in the low-temperature geothermal source. The main purpose is to identify suitable working fluids (wet, isentropic and dry flu-ids) which may yield high PPR (the ratio of power produced by the power generation subsystem to power consumed by the heat pump subsystem) value and QQR (the ratio of heat supplied to the user to heat produced by the geothermal source) value. Parameters under investigation were evaporating temperature, PPR value and QQR value. Results indicate that there exits an optimum evaporating temperature to maximize the PPR value and minimize the QQR value at the same time for individual fluid. And dry fluids show higher PPR values but lower QQR values. NH3 and R152a outstand among wet fluids. R134a out-stands among isentropic fluids. R236ea, R245ca, R245fa, R600 and R600a outstand among dry fluids. R236ea shows the highest PPR value among the recommended fluids.

关键词： organic Rankine cycle(ORC) low-temperature geothermal working fluids power generation heat production heat pump

Improving benzene catalytic oxidation on Ag/Co_(3)O_(4) by regulating the chemical states of Co and Ag

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Journal of Environmental Sciences 2024年第9期143卷 201-212页

作者： Hao guo tao guo Mengqi Zhao Yaxin Zhang Wenfeng Shangguan Yinnian Liao State Key Laboratory of Chemistry and Utilization of Carbon Based Energy Resources Xinjiang UniversityXinjiang 830017China Xinjiang Key Laboratory of Coal Clean Conversion&Chemical Engineering Process Xinjiang UniversityXinjiang 830017China School of Chemical Engineering and Technology Xinjiang UniversityXinjiang 830017China Research Center for Combustion and Environmental Technology Shanghai Jiao Tong UniversityShanghai 200240China School of Applied Chemistry and Materials Zhuhai College of Science and TechnologyGuangdong 519041China

Silver(9 wt.%)was loaded on Co_(3)O_(4)-nanofiber using reduction and impregnation methods,*** to the stronger electronegativity of silver,the ratios of surface Co^(3+)/Co^(2+) on Ag/Co_(3)O_(4) were higher than on Co_(3)O_(4),which further led to more adsorbed oxygen species as a result of the charge ***,the introducing of silver also obviously improved the reducibility of Co_(3)O_(4).Hence the Ag/Co_(3)O_(4) showed better catalytic performance than Co_(3)O_(4) in benzene *** with the Ag/Co_(3)O_(4) synthesized via impregnation method,the one prepared using reduction method(named as Ag Co-R)exhibited higher contents of surface Co^(3+) and adsorbed oxygen species,stronger reducibility,as well as more active surface lattice oxygen ***,Ag Co-R showed lowest T_(90) value of 183℃,admirable catalytic stability,largest normalized reaction rate of1.36×10^(-4)mol/(h·m^(2))(150℃),and lowest apparent activation energy(E_(a))of 63.2 kJ/*** analyzing of in-situ DRIFTS indicated benzene molecules were successively oxidized to phenol,o-benzoquinone,small molecular intermediates,and finally to CO_(2) and water on the surface of Ag *** last,potential reaction pathways including five detailed steps were proposed.

关键词： Reduction method Co_(3)O_(4)-supported Ag catalyst,VOCs Benzene oxidation Reaction mechanism

Pressure observer based adaptive robust trajectory tracking control of a parallel manipulator driven by pneumatic muscles

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第12期8卷 1928-1937页

作者： ZHU Xiao-cong tao guo-liang CAO Jian The State Key Laboratory of Fluid Power Transmission and Control Zhejiang University Hangzhou 310027 China

This paper presents a pressure observer based adaptive robust controller (POARC) for posture trajectory tracking of a parallel manipulator driven by three pneumatic muscles without pressure sensors. Due to model errors of the static forces and friction forces of pneumatic muscles, simplified average flow rate characteristics of valves, unknown disturbances of entire system, and unmeasured pressures, there exist rather severe parametric uncertainties, nonlinear uncertainties and dynamic uncertainties in modeling of the parallel manipulator. A nonlinear pressure observer is constructed to estimate unknown pressures on the basis of a single-input-single-output (SISO) decoupling model that is simplified from the actual multiple-input-multiple-output (MIMO) coupling model of the parallel manipulator. Then, an adaptive robust controller integrated with the pressure observer is developed to accomplish high precision posture trajectory tracking of the parallel manipulator. The experimental results indicate that the system with the proposed POARC not only achieves good control accuracy and smooth movement but also maintains robustness to disturbances.

关键词： Pneumatic muscle Parallel manipulator Pressure observer Adaptive robust control Trajectory tracking