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EQUATION OF AXISYMMETRICAL RING SHELLS WITH VARIABLE WALL THICKNESS IN COMPLEX QUANTITY AND ITS GENERAL solution

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Applied Mathematics and Mechanics(English Edition) 1989年第1期10卷 79-86页

作者：王慎行 China Tianjin Chemical Engineering corporation Tianjin

The purpose of this paper is to derive the equation of axisymmetrical ring shells with variable wall thickness in complex quantity and to give its general solution.

关键词： exp

Reliability-Based Load and Resistance Factors Design for Offshore Jacket Platforms in the Bohai Bay:Calibration on Target Reliability Index

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China Ocean Engineering 2009年第3期23卷 15-26页

作者：金伟良胡琦忠沈照伟时忠民 Institute of Structural Engineering Zhejiang University Research Centre of China National Offshore Oil corporation

The target reliability index has been effectively used as the best solution to deal with the relationship between the structural safety and the optimal economy in any structural design. However, the target reliability index for offshore jacket platforms based on different sea areas in China has never been calibrated. This paper presents an approach for its calibration, and suggests many kinds of associated load cases. The uncertainties of loads and structural resistance are mainly in- vestigated. The target reliability index for structural components, tubular joints and piles of offshore jacket plaffortns are discussed respectively in detail. Finally, through the calibrated results from the offshore jacket platforms of QK18-1, JZ20-2, SZ36-1 and BZ28-1 in the Bohai Bay, it is proposed to adopt 2.8 as the target reliability index of offshore jacket platforms in the Bohai Bay for a 25-year design period. The results provide significant reference for the design of offshore jacket platforms.

关键词： offshore jacket platform target reliability index calibration Bohai Bay

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Autotuning algorithm of particle swarm PID parameter based on D-Tent chaotic model

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Journal of Systems Engineering and Electronics 2013年第5期24卷 828-837页

作者： Min Zhu Chunling Yang Weiliang Li School of Electrical Engineering and Automation Harbin Institute of Technology China FAW Group corporation R&D Center

An improved particle swarm algorithm based on the D-Tent chaotic model is put forward aiming at the standard particle swarm algorithm. The convergence rate of the late of proposed algorithm is improved by revising the inertia weight of global optimal particles and the introduction of D-Tent chaotic sequence. Through the test of typical function and the autotuning test of proportionalintegral-derivative （PID） parameter, finally a simulation is made to the servo control system of a permanent magnet synchronous motor （PMSM） under double-loop control of rotating speed and current by utilizing the chaotic particle swarm algorithm. Studies show that the proposed algorithm can reduce the iterative times and improve the convergence rate under the condition that the global optimal solution can be got.

关键词： D-Tent particle swarm proportional-integral- derivative (PID) parameter optimization.

Synthesis and Characterization of Large Surface Area Yttrium Oxide by Precipitation Method

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Journal of Rare Earths 2004年第6期22卷 771-774页

作者：崔大立龙志奇张顺利崔梅生黄小卫 Grirem Advanced Materials corporation Limited General Research Institute for Non-Ferrous Metals Beijing 100088 China

The method for preparing yttrium oxide with large specific surface area was introduced. By means of BET, SEM, TG and DTA analysis, the effects of precipitant, stirring velocity, non-RE impurity in solution, calcination temperature, on the surface area were studied respectively. The Y_2O_3 sample with specific surface area of more than 60 m^2·g^(-1) and L.O.I less than 1% was prepared in the suitable precipitation condition and calcinations temperature when the ammonia used as precipitant. The SEM shows that the Y_2O_3 prepared with large surface area is the aggregation of about 50 nm particles.

关键词： surface area yttrium oxide morphology precipitation method rare earths

Poly(styrene-co-divinylbenzene)-PAMAM-IDA chelating resin: Synthesis, characterization and application for Ni(II) removal in aqueous

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Journal of Central South University 2014年第9期21卷 3479-3484页

作者：刘耀驰李学农王春志孔秀周荔子 College of Chemistry and Chemical Engineering Central South University Baling Company China Petroleum & Chemical Corporation

PS-PAMAM-IDA chelating resins were prepared by low-generations of polyamidoamine(PAMAM) and then chloroacetic acid functionalizing commercially available ammoniated polystyrene matrix, to preconcentrate Ni2+ from synthetic aqueous samples. Different generations of PAMAM were used to obtain different chelating resins, PS-IDA, PS-1.0G PAMAM-IDA and PS-2.0G PAMAM-IDA. The synthesized resins were characterized by FTIR and elemental analysis. The effect of solution pH, kinetic studies, resin loading capacity, matrix effects etc., on metal ion adsorption to adsorbent phase, were studied by batch method. The PS-1.0G PAMAM-IDA resin was the most excellent adsorbents, with a maximum adsorption capacity of(24.09±1.79) mg/g for Ni2+ ion at pH=7. The interpretation of the equilibrium data was given by Langmuir isotherms model, and the correlation coefficient values for PS-IDA, PS-1.0G PAMAM-IDA and PS-2.0G PAMAM-IDA resins were 0.992, 0.994 and 0.987, respectively.

关键词： chelating resin polyamidoamine iminodiacetic acid properties Ni(II)

Cascaded channel decoupling based solution for RIS regulation matrix

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Intelligent and Converged Networks 2024年第1期5卷 19-27页

作者： Yajun Zhao Beijing Institute of Technology Beijing 100081China ZTE corporation Beijing 100029China

This article presents a pioneering solution to address the challenges of reconfigurable intelligent surface(RIS),employing a cascaded channel decoupling *** novel method streamlines the RIS regulation matrix by dividing the process of electromagnetic wave modulation into two separate sub-processes:virtual receiving response and virtual regular transmission,resulting in the decoupling of the RIS cascaded ***,the paper explores the practical implementation of this channel decoupling method in two typical scenarios,including single-user and multi-user access,offering detailed insights into its *** numerical simulations,the article demonstrates the effectiveness and reduced complexity of the proposed scheme in enhancing the efficiency of the RIS regulation matrix.

关键词： reconfigurable intelligent surface channel decoupling receiving matrix transmitting matrix

Optimal Decomposition of Stochastic Dispatch Schedule for Renewable Energy Cluster

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Journal of Modern Power Systems and Clean Energy 2021年第4期9卷 711-719页

作者： Yue Yang Wenchuan Wu Bin Wang Mingjie Li Tao Zhu State Key Laboratory of Power Systems Department of Electrical EngineeringTsinghua UniversityBeijing 100084China National Electric Power Control Center of State Grid corporation of China BeijingChina Kunming Electric Power Supply Company of Yunnan Power Grid corporation KunmingChina

The correlated renewable energy farms are usually aggregated as a cluster in economic dispatch to relieve computational *** strategy can also achieve better performance since the precision of predicting the power generation of a cluster can be higher than those of individual *** paper proposes an optimal decomposition method to allocate dispatch schedules among renewable energy farms(REFs)in the cluster under existing stochastic optimization *** proposed model takes advantage of probabilistic characteristics of renewable generation to minimize the curtailment and ensure the feasibility of dispatch schedule of the *** tractable formulation and efficient solution method are the proposed to solve the proposed *** tests show that the proposed method achieves the optimal decomposition of dispatch schedule among REFs and facilitates the utilization of renewable generation.

关键词： Renewable energy stochastic optimization economic dispatch decomposition of dispatch schedule

Time-to-go weighted optimal trajectory shaping guidance law

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Journal of Beijing Institute of Technology 2011年第3期20卷 317-323页

作者：王辉林德福程振轩 School of Aerospace Engineering Beijing Institute of Technology China North Industries Group corporation

For maneuvering target, the optimal trajectory shaping guidance law which can simultaneously achieve the designed specifications on miss distance and final impact angle was deduced using optimal control theory based on the time-to-go weighted function. Based on the same cost function, the closed-form solutions of the guidance law were derived when the initial displacement of missile, final impact angle, heading error and target maneuver was introduced into the lag-free guidance system. To validate the closed-form solutions, the simulation of the lag-free system was done and the simulation results exactly matched the closed-form solutions and only when the exponent is greater than zero, the final acceleration approaches to zero.

关键词： trajectory shaping guidance optimal control time-to-go close-form solution

Characteristic analysis of liquid forced nonlinear sloshing under low-gravity

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Journal of Harbin Institute of Technology(New Series) 2007年第6期14卷 817-822页

作者：贺元军王萍萍马兴瑞王本利 Center of Satellite Technology Harbin Institute of Technology China Aerospace Science and Technology corporation

Under low gravity,the Lagrange equations in the form of volume integration of pressure of nonlinear liquid sloshing were built by variational principle. Based on this,the analytical solution of nonlinear liquid sloshing in pitching tank could be investigated. Then the velocity potential function was expanded in series by wave height function at the free surface so that the nonlinear equations with kinematics and dynamics free surface boundary conditions were derived. Finally,these nonlinear equations were investigated analytically by the multiple scales method. The result indicates that the system's amplitude-frequency response changes from ‘soft-spring’ to ‘hard-spring’ in the planar motion with the decreasing of the Bond number,while it changes from ‘hard-spring’ to ‘soft-spring’ in the rotary motion.

关键词： circle cylindrical tank nonlinear sloshing low-gravity soft-spring and hard-spring characteristic