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Mineral Coated Fertilizer Effect on Nitrogen-Use Efficiency and Yield of Wheat

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Pedosphere 2005年第4期15卷 526-531页

作者： LI Jian-Yun HUA Quan-Xian TAN jin-Fang Zhou Jian-Min hou Yan-Lin L Department of Soil Environmental science Research Center for Eco-Environmental Science Chinese Academy of Sciences Beijing 100085 （China）. State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil Science Chinese Academy of Sciences Nanjing 210008 （China） Graduate School of the chinese academy of sciences Beijing 100039 （China） College of Agriculture Henan Agricultural University Zhengzhou 450002 （China）

A field experiment with winter wheat （Triticum aestivurn L.） was conducted on a silt loam calcaric endorusti-ustic Cambosols derived from the Yellow River alluvial deposits in Henan, china, from 2.01 to 2.02.to evaluate N recovery and agronomic performance of different mineral coated fertilizers （MiCFs） compared to normal urea used in wheat cropping systems under field conditions. Five treatments, including CK （check, no N fertilizer）, urea and three different MiCFs at an equivalent N application rate were established in a randomized complete block design. N release from MiCFs in soil was more synchronous with the N requirement of wheat throug{2.t the growth stages than that from urea, with grain yield of the MiCF treatments significantly higher （P 〈 0.05） than that of the treatment urea. Correspondingly, the N recovery rate was greater for all MiCFs compared to urea, increasing from 32.8% up to 50.1%. Due to its high recovery and low cost, use of the mineral coated N fertilizers was recommended instead of the polymer coated N fertilizers.

关键词： mineral coated fertilizer N recovery urea winter wheat

Time-varying sliding mode control for a class of uncertain MIMO nonlinear system subject to control input constraint

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science china(Information {2.) 2010年第1期53卷 89-100页

作者： jin YongQiang1,2. LIU XiangDong1, QIU Wei2.& hou ChaoZhen1 1Department of Automatic Control, {2. Institute of Technology, {2. 100081,{2. 2.erospace System Engineering Shanghai, Shanghai 2.1108,{2. 1. Department of Automatic Control Beijing Institute of Technology Beijing 100081 China2. Aerospace System Engineering Shanghai Shanghai 201108 China

To solve the regulator problem of a class of uncertain MIMO nonlinear systems subject to control input constraint, three types of time-varying sliding mode control laws are proposed. The sliding surfaces pass the initial value of the system at the initial time, and are shifted/rotated towards the predetermined ones. The controller parameters are optimized by genetic algorithm (GA). Lyapunov method is adopted to prove the stability and robustness to the parameter uncertainties and external disturbance. By mean of time-varying sliding mode control law, the reaching phase in the conventional sliding mode control is eliminated, and the system is guaranteed to have robustness from the very beginning. Taking the control of two-link manipulator and attitude tracking of rigid spacecraft as two examples, we illustrate the features of the time-varying sliding mode control. The simulation results show the validity of the control law to a class of uncertain MIMO systems. Better robustness against the uncertainties and external disturbance could be achieved by time-varying sliding mode control wit{2.t violating the constraint on control input.

关键词： time-varying sliding surface sliding mode control MIMO nonlinear system uncertain control input constraints

Stepped-up development of accelerator mass spectrometry method for the detection of ^(60)Fe with the HI-13 tandem accelerator

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Nuclear science and Techniques 2024年第4期35卷 136-143页

作者： Yang Zhang Sheng-Quan Yan Ming He Qing-Zhang Zhao Wen-Hui Zhang Chao-Xin Kan Jian-Ming Zhou Kang-Ning Li Xiao-Fei Wang Jian-Cheng Liu Zhao-Hua Peng Zhuo Liang Ai-Ling Li Jian Zheng Qi-Wen Fan Yun-Ju Li You-Bao Wang zhi-Hong Li Yang-Ping Shen Ding Nan Wei Nan Yu-Qiang Zhang Jia-Ying-Hao Li Jun-Wen Tian Jiang-Lin hou Chang-Xin Guo zhi-Cheng Zhang Ming-Hao Zhu Yu-Wen Chen Yu-Chen Jiang Tao Tian jin-Long Ma Yi-Hui Liu jing-Yu Dong Run-Long Liu Mei-Yue-Nan Ma Yong-Shou Chen Wei-Ping Liu Bing Guo china Institute of Atomic Energy P.O.Box 275(10)Beijing 102413China College of science Southern University of Science and TechnologyShenzhen 518055China School of Physics Xi’an Jiaotong UniversityXi’an 710049China

The Moon provides a unique environment for investigating nearby astrophysical events such as *** samples retain valuable information from these events,via detectable long-lived“fingerprint”radionuclides such as^(60)*** this work,we stepped up the development of an accelerator mass spectrometry(AMS)method for detecting^(60)Fe using the HI-13tandem accelerator at the china Institute of Atomic Energy(CIAE).Since interferences could not be sufficiently removed solely with the existing magnetic systems of the tandem accelerator and the following Q3D magnetic spectrograph,a Wien filter with a maximum voltage of±60 kV and a maximum magnetic field of 0.3 T was installed after the accelerator magnetic systems to lower the detection background for the low abundance nuclide^(60)Fe.A 1μm thick Si_(3)N_(4) foil was installed in front of the Q3D as an energy *** particle detection,a multi-anode gas ionization chamber was mounted at the center of the focal plane of the ***,an^(60)Fe sample with an abundance of 1.12.×10^(-10)was used to test the new AMS *** results indicate that^(60)Fe can be clearly distinguished from the isobar^(60)*** sensitivity was assessed to be better than 4.3×10^(-14)based on blank sample measurements lasting 5.8 h,and the sensitivity could,in principle,be expected to be approximately 2.5×10^(-15)when the data were accumulated for 100 h,which is feasible for future lunar sample measurements because the main contaminants were sufficiently separated.

关键词： Accelerator mass spectrometry Wien filter Isobar separation Supernovae Chang'e-5 lunar samples

Numerical modeling of gravitational erosion in rill systems

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International Journal of Sediment Research 2011年第4期26卷 403-415页

作者： Peng HAN,jin-Ren NI,Ke-Bin hou,Chi-Yuan MIAO,and Tian-Hong LI 1 Assoc.Prof,2.Prof.,3 Master,4 Dr.,5 Assoc.Prof.,Department of Environmental Engineering,Peking University,{2. 100871,P.R.china,The Key Laboratory of Water and Sediment {2.,Ministry of Education,P.R.china, [a] Assoc. Prof. Department of Environmental Engineering Peking University Beijing 100871 P. R. China The Key Laboratory of Water and Sediment Sciences Ministry of Education P. R. China [b] Prof. Department of Environmental Engineering Peking University Beijing 100871 P. R. China The Key Laboratory of Water and Sediment Sciences Ministry of Education P. R. China [c] Master Department of Environmental Engineering Peking University Beijing 100871 P. R. China The Key Laboratory of Water and Sediment Sciences Ministry of Education P. R. China [d] Dr. Department of Environmental Engineering Peking University Beijing 100871 P. R. China The Key Laboratory of Water and Sediment Sciences Ministry of Education P. R. China [e] Assoc. Prof. Department of Environmental Engineering Peking University Beijing 100871 P. R. China The Key Laboratory of Water and Sediment Sciences Ministry of Education P. R. China

A self-organizing model was developed for simulating rill erosion process on slopes with particular attention to the role of gravitational *** a complete simulation circle,processes such as precipitation,infiltration,runoff,scouring,gravitational erosion and elevation variation were fully *** time(or runoff time) was regarded as iteration benchmark in the *** specify the contribution of gravitational erosion to the process of rill formation and development,a gravitational erosion module was inserted into the *** erosion in rill development was regarded as a Gaussian random process.A model was calibrated by our experimental data,and further validated satisfactorily with 2. runs of experimental results from different investigators. Systematic comparison was made between sediment yields with and without consideration of gravitational erosion *** was demonstrated that the model could reasonably simulate the rill erosion process under a variety of slope gradients,rainfall intensities and soil conditions upon the gravitational erosion being ***,the role of gravitational erosion on sediment yields in rill systems varies significantly under different conditions,although it is of the utmost importance in steeper *** process of gravitational erosion in rill development was studied by a newly-defined parameter a>,which is defined as the volume ratio of gravitational erosion over hydraulic-related *** gravitational contribution to the total erosion could be over 50%for the rill systems with higher rainfall intensity and steeper slopes.

关键词： Self-organizing model Rill erosion Gravitational erosion Gaussian noise

A Discrete-time Periodic Adaptive Control for systems in the Presence of Nonsector Nonlinearities

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A Discrete-time Periodic Adaptive Control for Systems in the...

A Discrete-Time Adaptive Iterative Learning from Different Reference Trajectory for Linear Time-Varying systems

第三十届中国控制会议

作者： CHI Ronghu~1,ZHANG Yongbo~1,jin Shangtai~2.hou Zhongsheng~2.1.School of Automation & Electronics Engineering,Qingdao University of {2. & Technology,Qingdao 2.6042.P.R.china 2.Advanced Control {2. Lab,School of Electronics & Information Engineering,beijing Jiaotong University,beijing 100044,P.R. china

A new periodic least-squares estimator with nonlinear data weighting is developed and used to design a periodic adaptive control for a simple discrete-time nonlinear system in the presence of time-varying parametric uncertainties.A global stability result is obtained through Lyapunov analysis without assuming any growth conditions on the nonlinearities. Simulation results further confirm the effectiveness of the presented methods.

关键词： Periodic Adaptive Control Periodic Least-squares Nonlinear Data Weighting Time-varying Nonlinear System

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A Discrete-Time Adaptive Iterative Learning from Different R...

A Discrete-time AILC for systems with Non-parametric Uncertainties

第三十一届中国控制会议

作者： CHI Ronghu~1 WANG Danwei~2.hou Zhongsheng~3 jin Shangtai~3 ZHANG Dexia~1 1.School of Automation & Electrical Engineering Qingdao University of {2. & Technology Qingdao 2.6042.2.EXQUISITUS Centre for E-City School of Electrical & Electronic Engineering Nanyang Technological University Singapore 639798 3.Advanced Control systems Lab School of Electronics & Information Engineering {2. Jiaotong University {2. 100044

＜正＞An adaptive ILC approach is presented for a linear MIMO discrete-time system to track different reference trajectory. The presented adaptive ILC is a data-driven approach in nature and the controller does not contain any modeling information of the *** unknown Markov parameter of the plant is iteratively estimated only using the I/O data of the *** rigorous analysis shows the asymptotic convergence of the presented method for iteration-varying reference trajectory.

关键词： Adaptive ILC Discrete-Time Linear time-varying systems Different reference trajectory Data-driven control

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A Discrete-time AILC for Systems with Non-parametric Uncerta...

Different Roles of a Boron Substitute for Carbon and Silicon in β-SiC

第二十九届中国控制会议

作者： CHI Ronghu1,hou Zhongsheng2.jin Shangtai2.1.School of Automation&Electrical Engineering,Qingdao University of {2.&Technology,Qingdao 2.6042.P.R.china2.Advanced Control {2. Lab,School of Electronics and Information Engineering,beijing Jiaotong University,beijing 100044,P.R.china

In this paper,a discrete adaptive ILC is presented for a time-varying nonlinear system with nonparametric uncertainties.A novel estimation of nonparametric uncertainties is constructed just using the past I/O data,and the uncertainties are completely compensated such that the output tracking error is only affected by external *** a main contribution of this paper,all the discussions are done with the random initial condition and the iteration-varying target *** the rigorous mathematical analysis and the simulation results illustrate the correctness and effectiveness of the proposed approach.

关键词： Adaptive Iterative learning control Non-parametric Uncertainties Random Initial Condition Iteration-varying Trajectories Discrete-time systems

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chinese Physics Letters 2012年第7期29卷 214-217页

作者： Zhou Yan WANG Kun FANG Xiao-Yong hou {2.-Ling jin Hai-Bo CAO Mao-Sheng School of science Yanshan UniversityQinghuangdao 066004 School of Materials science and Engineering Beijing Institute of TechnologyBeijing 100081

The first-principles numerical simulation is employed-to calculate the effect of replacement of carbon and silicon with boron on the electronic structure and optical properties of β-*** analysis shows that the B impurity bond lengths shrink in the case of Bsi,while they expand with reference to *** addition,Bsi contains C-C,Si-Si and B-Si *** calculated results show that the two systems of Bc and Bsi apply different *** is in accordance with the Lorentz dispersion theory while Bsi follows the Drude dispersion *** analysis and quantitative calculation are used for conductivity spectra in the infrared region.

关键词： dispersion analysis boron

面向复杂产品研制的MBSE体系架构及其发展趋势研究

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控制与决策 2022年第12期37卷 3073-3082页

作者：王文跃侯俊杰毛寅轩靳捷卢志昂中国航天系统科学与工程研究院系统工程研究所北京100037

基于模型的系统工程(model based systems engineering,MBSE)是一种将系统工程理论与数字化技术相结合的复杂产品研制技术,能够以系统工程思维有效驱动复杂产品研制流程,并以系统模型方式形式化地表达系统复杂交互作用.对此,首先以复杂... 详细信息

基于模型的系统工程(model based systems engineering,MBSE)是一种将系统工程理论与数字化技术相结合的复杂产品研制技术,能够以系统工程思维有效驱动复杂产品研制流程,并以系统模型方式形式化地表达系统复杂交互作用.对此,首先以复杂产品研制背景、MBSE国内外发展状况为理论基础,总结并介绍目前MBSE在复杂产品研制过程中存在的问题;其次,以MBSE模型域、技术域、功能域、跨域支撑要素和应用域为研究层面,结合人工智能、数字孪生、数字主线等数字化技术综合考虑MBSE工程实践所需的关键要素,提出一种面向复杂产品研制的MBSE体系架构并进行详细论述;最后,基于该体系架构研判目前MBSE发展形势,并以数据模型为核心生产要素的角度进一步探讨未来MBSE的发展趋势.

关键词：基于模型的系统工程(MBSE) 数字化技术复杂产品研制体系架构系统模型