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Unsupervised FIR adaptive filtering and its frequency domain analysis

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Journal of beijing institute of Technology 2012年第2期21卷 234-239页

作者：李振华陈家斌马韬 School of Automation Beijing Institute of Technology Military representative office at North China Optical Instrument Company Limited

An unsupervised minimum mean square error FIR adaptive filtering （UAF） algorithm is proposed to estimate the system＇ s input signal. The algorithm only uses the system＇ s output signal and noise variance without requiring knowledge of a reference signal. The frequency analysis shows that the UAF is a multi-spot bandpass filter with passing frequency determined by the system＇ s input signal. Namely, the UAF chooses the expected frequency and extremely restricts the unwanted fre- quency signal by using weight-updating scheme in time domain. However, the UAF presents the Gibbs phenomenon since the ideal filter is infinitely long which is unrealizable. The simulation and experimental results show that the UAF could effectively reduce the amplitude of the noise and im- prove the signal to noise ratio.

关键词： unsupervised adaptive filtering mean square error frequency analysis

Corrosion and electrochemical behavior of as-cast Mg-5Y-7Gd-1Nd-0.5Zr magnesium alloys in 5%NaCl aqueous solution

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Progress in Natural Science:Materials International 2011年第4期21卷 314-321页

作者： Xin ZHANG~(1,2,3),Kui ZHANG~1,Xing-gang LI~1,Cong WANG~4,Hong-wei LI~(2,3),Chang-shun WANG~(2,3),Xia DENG~1 1.State Key Laboratory for Fabrication and Processing of Nonferrous Metals, beijing General Research institute for Nonferrous Metals,beijing 100088,China 2.beijing Engineering Research Center for Advanced Manufacturing and Evaluation of Special Vehicle Parts,beijing 100072,China 3.institute of Technology,beijing North Vehicle Group Corporation,beijing 100072,China 4.Fengtai Military representative office,beijing Military representative office,PLA,beijing 100072,China [a] State Key Laboratory for Fabrication and Processing of Nonferrous Metals Beijing General Research Institute for Nonferrous Metals Beijing 100088 China [b] beijing Engineering Research Center for Advanced Manufacturing and Evaluation of Special Vehicle Parts Beijing 100072 China [c] institute of Technology Beijing North Vehicle Group Corporation Beijing 100072 China [d] Fengtai Military representative office Beijing Military Representative Office PLA Beijing 100072 China

The corrosion mechanism of the as-cast Mg-5Y-7Gd-1Nd-0.5Zr magnesium alloy immersed in 5%NaCl aqueous solution was investigated by electrochemical test and *** electrochemical results indicate that the corrosion resistance of Mg-5Y-7Gd-1Nd-0.5Zr alloy in 5%NaCl aqueous solution gradually deteriorates with immersion time increasing from 2 h,24 h,60 h,to 108 h,which is consistent with the SEM observation of corrosion *** Cl-anion leads to the initiation and development of the corrosion pits,and Mg-5Y-7Gd-1Nd-0.5Zr alloy exhibits filiform type of attack under significant anodic control of magnesium solution *** corrosion potential becomes noble with increasing immersion time.

关键词： magnesium alloys Mg-5Y-7Gd-1Nd-0.5Zr corrosion electrochemical behavior

Analysis Model on Penetration Depth of Concrete by Eroding Long-Rod Projectiles

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Journal of beijing institute of Technology 2010年第4期19卷 395-398页

作者：练兵蒋建伟门建兵王树有 State Key Laboratory of Explosion Science and Technology Beijing Institute of Technology Military representative office of Air Force in Xiangfan Area Xiangfan

Mass loss should be considered while calculating the penetration depth of concrete by eroding long-rod projectiles of high *** penetration process is divided into two phases：eroding phase and rigid *** eroding phase,a model to predict the penetration depth is established on the assumption that there is a chipping region in the bottom of *** rigid phase,Forrestal formula is adopted to calculate the penetration *** this model,the depth of concrete penetration by a tungsten alloy long-rod projectile is *** the critical eroding velocity is between 950 m/s and 1 000 m/s,the result is in good agreement with the experimental data.

关键词： eroding long-rod projectile penetration concrete

Anti-interference self-alignment algorithm by attitude optimization estimation for SINS on a rocking base

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Journal of Systems Engineering and Electronics 2023年第5期34卷 1333-1342页

作者： XUE Haijian WANG Tao CAI Xinghui WANG Jintao LIU Fei High-Tech institute of Xi’an Xi’an 710025China Military representative office of Rocket Army Equipment Department Qingdao 266071China

The performance of a strapdown inertial navigation system(SINS)largely depends on the accuracy and rapidness of the initial alignment.A novel anti-interference self-alignment algorithm by attitude optimization estimation for SINS on a rocking base is presented in this *** algorithm transforms the initial alignment into the initial attitude determination problem by using infinite vector observations to remove the angular motions,the SINS alignment is heuristically established as an optimiza-tion problem of finding the minimum *** order to further improve the alignment precision,an adaptive recursive weighted least squares(ARWLS)curve fitting algorithm is used to fit the translational motion interference-contaminated reference vectors according to their time domain *** studies and experimental results favorably demonstrate its rapidness,accuracy and robustness.

关键词： strapdown inertial navigation system(SINS) initial alignment anti-interference rocking base adaptive recursive weighted least squares(ARWLS)

Gas–liquid mass transfer and flow phenomena in the Peirce–Smith converter: a water model study

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International Journal of Minerals,Metallurgy and Materials 2018年第1期25卷 37-44页

作者： Xing Zhao Hong-liang Zhao Li-feng Zhang Li-qiang Yang institute of Process Engineering Chinese Academy of ScienceBeijing 100190China School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China beijing Key Laboratory of Green Recycling and Extraction of Metal Beijing 100083China Chambishi Copper Smelter Ltd. Beijing Representative OfficeBeijing 100029China

A water model with a geometric similarity ratio of 1：5 was developed to investigate the gas-liquid mass transfer and flow charac- teristics in a Peirce-Smith converter. A gas mixture of CO2 and Ar was injected into a NaOH solution bath. The flow field, volumetric mass transfer coefficient per unit volume （Ak/V; where A is the contact area between phases, V is the volume, and k is the mass transfer coeffi- cient）, and gas utilization ratio （t/） were then measured at different gas flow rates and blow angles. The results showed that the flow field could be divided into five regions, i.e., injection, strong loop, weak loop, splashing, and dead zone. Whereas the Ak/V of the bath increased and then decreased with increasing gas flow rate, and n steadily increased. When the converter was rotated clockwise, both Ak/F and t/increased. However, the flow condition deteriorated when the gas flow rate and blow angle were drastically increased. Therefore, these para- meters must be controlled to optimal conditions. In the proposed model, the optimal gas flow rate and blow angle were 7.5 m3.h-1 and 10°, respectively.

关键词： Peirce-Smith converter water model mass transfer flow phenomena volumetric mass transfer coefficient

Water model experiments of multiphase mixing in the top-blown smelting process of copper concentrate

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International Journal of Minerals,Metallurgy and Materials 2016年第12期23卷 1369-1376页

作者： Hong-liang Zhao Pan Yin Li-feng Zhang Sen Wang School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China beijing Key Laboratory of Green Recycling and Extraction of Metal Beijing 100083China Chambishi Copper Smelter Ltd. Beijing Representative OfficeBeijing 100029China

We constructed a 1：10 cold water experimental model by geometrically scaling down an Isa smelting furnace. The mixing processes at different liquid heights, lance diameters, lance submersion depths, and gas flow rates were subsequently measured using the conductivity method. A new criterion was proposed to determine the mixing time. On this basis, the quasi-equations of the mixing time as a function of different parameters were established. The parameters of the top-blown smelting process were optimized using high-speed photography. An excessively high gas flow rate or excessively low liquid height would enhance the fluctuation and splashing of liquid in the bath, which is unfavorable for material mixing. Simultaneously increasing the lance diameter and the lance submersion depth would promote the mixing in the bath, thereby improving the smelting efficiency.

关键词： copper smelting multiphase flow mixing water modeling

Gas–liquid mass transfer and flow phenomena in a peirce–smith converter: A numerical model study

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International Journal of Minerals,Metallurgy and Materials 2019年第9期26卷 1092-1104页

作者： Hong-liang Zhao Xing Zhao Liang-zhao Mu Li-feng Zhang Li-qiang Yang School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China beijing Key Laboratory of Green Recycling and Extraction of Metal Beijing 100083China beijing representative office of Chambishi Copper Smelter Ltd. Beijing 100029China

A numerical model was established to simulate the flow field in a Peirce–Smith converter bath, which is extensively adopted in copper making. The mean phase and velocity distribution, circular area, and mean wall shear stress were calculated to determine the optimal operation parameter of the converter. The results showed that the slag phase gathered substantially in the dead zone. The circular flow was promoted by increasing the gas flow rate, Q, and decreasing the nozzle height, h. However, these operations significantly aggravate the wall shear stress. Reducing the nozzle diameter, d, increases the injection velocity, which may accelerate the flow field. However, when the nozzle diameter has an interval design, the bubble behaviors cannot be combined, thus, weakening the injection efficiency. Considering the balance between the circular flow and wall shear stress in this model, the optimal operation parameters were Q = 30000–35000 m^3/h, h = 425–525 mm, and d = 40 & 50 mm.

关键词： phase distribution velocity distribution wall shear stress Peirce–Smith converter

Thermo-physical Properties of Continuous Carbon Fiber Reinforced Copper Matrix Composites

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材料工程 2007年第z1期35卷 61-65页

作者：曹金华黄俊波陈先有 Army Aviation representative office

Continuous carbon fiber reinforced copper matrix composites with 70%(volume fraction) of carbon fibers prepared by squeeze casting technique have been used for investigation of the coefficient of thermal expansion(CTE) and thermal ***-physical properties have been measured in both,longitudinal and transversal directions to the fiber *** results showed that Cf/Cu composites may be a suitable candidate for heat sinks because of its good thermo-physical properties *** low CTE(4.18×10-6/K) in longitudinal orientation and(14.98×10-6/K) in transversal orientation at the range of 20-50℃,a good thermal conductivity(87.2 W/m·K) in longitudinal orientation and(58.2 W/m·K) in transversal *** CTE and thermal conductivity values are compared with those predicted by several well-known *** model gave better results for prediction of the CTE and thermal conductivity of the unidirectional composites.

关键词： carbon fiber copper matrix composites thermal expansion thermal conductivity

Domain ontology driven composable simulation framework

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Journal of Harbin institute of Technology(New Series) 2012年第4期19卷 49-54页

作者：陈欣段枫张英潮 School of Computer Science and Technology Beijing University of Posts and Communications State Key Lab for Complex Systems Simulation Military representative office in beijing Area of PLA

The simulation composability is one of important development directions in simulation domain. The key issue is the semantic composability. Currently there is no feasible approach to realize the effective semantic representation and composition of simulation components. Based on domain knowledge and Web Ontology Language (OWL), this paper proposes a composable simulation framework, which includes conceptual model semantics, model components semantics, model framework semantics, and simulation scenario semantics. Additionally, all the semantics are utilized in the model components development process, the simulation system development process, and the simulation system execution process respectively. The consistency checking among those semantics is also proposed. The detailed mapping processes between different semantic models can help to build the domain ontology driven composable simulation system.

关键词： domain ontology composability simulation components conceptual model simulation scenario