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Selective Ensemble Extreme Learning Machine Modeling of Effluent Quality in Wastewater Treatment Plants

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International Journal of Automation and computing 2012年第6期9卷 627-633页

作者： Li-Jie Zhao 1,2 Tian-You Chai 2 De-Cheng Yuan 1 1 College of Information engineering,shenyang university of Chemical technology,shenyang 110042,china 2 State Key Laboratory of Synthetical Automation for Process Industries,Northeastern university,shenyang 110189,china 1. College of Information engineering Shenyang University of Chemical Technology Shenyang 110042 China 2. State Key Laboratory of Synthetical Automation for Process Industries Northeastern University Shenyang 110189 China

Real-time and reliable measurements of the effluent quality are essential to improve operating efficiency and reduce energy consumption for the wastewater treatment *** to the low accuracy and unstable performance of the traditional effluent quality measurements,we propose a selective ensemble extreme learning machine modeling method to enhance the effluent quality *** learning machine algorithm is inserted into a selective ensemble frame as the component model since it runs much faster and provides better generalization performance than other popular learning *** extreme learning machine models overcome variations in different trials of simulations for single *** ensemble based on genetic algorithm is used to further exclude some bad components from all the available ensembles in order to reduce the computation complexity and improve the generalization *** proposed method is verified with the data from an industrial wastewater treatment plant,located in shenyang,*** results show that the proposed method has relatively stronger generalization and higher accuracy than partial least square,neural network partial least square,single extreme learning machine and ensemble extreme learning machine model.

关键词： Wastewater treatment process effluent quality prediction extreme learning machine selective ensemble model genetic algorithm.

Influence of Hot Rolling Conditions on the Mechanical Properties of Hot Rolled TRIP Steel

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Journal of Wuhan university of technology(Materials Science) 2008年第1期23卷 74-79页

作者：李壮 WU Di Department of Materials engineering Shenyang Institute of Aeronautical Engineering Shenyang 110034 China The State Key Laboratory of Rolling and Automation Northeastern University Shenyang 110004 China

Influence of hot rolling conditions on the mechanical properties of hot rolled TRIP steel was investigated. Thermomechanical control processing （TMCP） was conducted by using a laboratory hot rolling mill, in which three different kinds of finish rolling temperatures were applied. The results show that polygonal ferrite, granular bainite and larger amount of stabilized retained austenite can be obtained by controlled rolling processes. The finer ferrite grain size is produced through the deformation induced transformation during deformation rather than after deformation, which affects the mechanical properties of hot rolled TRIP steel. Mechanical properties increase with decreasing finish rolling temperature due to the stabilization of retained austenite. Ultimate tensile strength （UTS）, total elongation （TEL） and the product of ultimate tensile strength and total elongation （UTS×TEL） reaches optimal values （791 MPa, 36% and 28 476 MPa%, respectively） when the specimen was hot rolled for 50% reduction at finish rolling temperature of 700 ℃.

关键词： hot rolling conditions retained austenite hot rolled TRIP steels mechanical properties

Generating function approach to reliability analysis of structural systems

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Science china(Technological Sciences) 2009年第10期52卷 2849-2858页

作者： ZHOU JinYu1 & XIE LiYang2 1 Jiangsu Teacher’s university of technology, Changzhou 213001, china 2 Northeastern university, shenyang 110004, china 1. Jiangsu Teacher’s university of technology Changzhou 213001 China 2. Northeastern university Shenyang 110004 China

The generating function approach is an important tool for performance assessment in multi-state systems. Aiming at strength reliability analysis of structural systems, generating function approach is introduced and developed. Static reliability models of statically determinate, indeterminate systems and fatigue reliability models are built by constructing special generating functions, which are used to describe probability distributions of strength (resistance), stress (load) and fatigue life, by defining composite operators of generating functions and performance structure functions thereof. When composition operators are executed, computational costs can be reduced by a big margin by means of collecting like terms. The results of theoretical analysis and numerical simulation show that the generating function approach can be widely used for probability modeling of large complex systems with hierarchical structures due to the unified form, compact expression, computer program realizability and high universality. Because the new method considers twin loads giving rise to component failure dependency, it can provide a theoretical reference and act as a powerful tool for static, dynamic reliability analysis in civil engineering structures and mechanical equipment systems with multi-mode damage coupling.

关键词： structure reliability generating function static strength failure fatigue failure failure dependence

Effect of Preparation Methods on Mechanical Properties of PVA/HA Composite Hydrogel

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Journal of Bionic engineering 2010年第3期7卷 235-243页

作者： Dekun Zhang~1, Junjie Duan~1, Dagang Wang~2, Shirong Ge~2 1. school of Materials Science and engineering, china university of Mining and technology Xuzhou 221116, P. R. china 2. school of Mechanical and electrical engineering, china university of Mining and technology, Xuzhou 221116, P. R. china [a] school of Materials Science engineering China University of Mining technology Xuzhou 221116 P. R. China [b] School of Mechanical electrical engineering China University of Mining technology Xuzhou 221116 P. R. China

Poly(vinyl alcohol) (PVA)/hydroxyapatite (HA) composite hydrogel specimens were prepared with 15% PVA and 1%,2%, 3%, 4% and 5% HA by repeated freezing-thawing. The tests of static and dynamic mechanical properties were carried out todiscuss the influence of different contents of HA and freezing-thawing cycles on the mechanical properties of PVA/HA compositehydrogel. The results of static mechanical tests showed that the PVA/HA composite hydrogel with 3% HA and ninefreezing-thawing cycles had excellent stress relaxation properties, higher relaxation ratio, lower stress equilibrium value andpresented better properties of creep and recovery. The results of dynamic mechanical test showed that the PVA/HA compositehydrogel with nine freezing-thawing cycles had higher storage modulus and loss modulus, so was the PVA/HA compositehydrogel with 3% HA.

关键词： composite hydrogel HA contents freezing-thawing cycles static properties dynamic properties

Mechanical and Frost-resistance Properties of Rural Area Building Waste Hollow Bricks

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Journal of Wuhan university of technology(Materials Science) 2010年第6期25卷 1017-1021页

作者：刘军 school of Material Science and engineering Shenyang Jianzhu University

Serving as recycled coarse aggregate,the pretreated rural building waste was added into the concrete hollow bricks in the varying replacement of 0,20%,40%,60%,80% and 100%.By testing its compressive strength,flexural strength,mass and strength loss after freeze-thaw cycles,the impact of the different replacement on mechanical and frost-resistance properties of concrete hollow bricks was presented through SEM *** experimental results show that,with the increase in recycled coarse aggregate replacement rate,the mechanical and frost-resistance properties show a downward trend;when the replacement rate is 40%,28 d compressive strength and flexural strength of concrete hollow brick demonstrate the good peak value which meet the requirement of the national standard for ordinary small concrete hollow bricks;the interfacial structures of the pretreated recycled concrete is more complicated than those of concrete made of natural aggregate,but the former enjoys better interface bonding and tight structure.

关键词： replacement rate waste clay brick mechanical properties frost-resistance properties microstructure

Control allocation and management of redundant control effectors based on bases sequenced optimal method

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Science china(Technological Sciences) 2010年第2期53卷 577-583页

作者： YANG LingYu1, FAN YanMing2, SHAO Shan2, ZHONG YouWu1 & SHEN GongZhang1 1 Department of Automation Science and electrical engineering, Beihang university, Beijing 100191, china 2 shenyang Aircraft Design and Research Institute, shenyang 110035, china 1. Department of Automation Science and electrical engineering Beihang University Beijing 100191 China2. Shenyang Aircraft Design and Research Institute Shenyang 110035 China

For an advanced aircraft, the amount of its effectors is much more than that for a traditional one, the functions of effectors are more complex and the coupling between each other is more severe. Based on the current control allocation research, this paper puts forward the concept and framework of the control allocation and management system for aircrafts with redundancy con-trol effectors. A new optimal control allocation method, bases sequenced optimal (BSO) method, is then presented. By analyz-ing the physical meaning of the allocation process of BSO method, four types of management strategies are adopted by the system, which act on the control allocation process under different flight conditions, mission requirements and effectors work-ing conditions. Simulation results show that functions of the control allocation system are extended and the system adaptability to flight status, mission requirements and effector failure conditions is improved.

关键词： aircraft with multiple control effectors flight control management

Early Age Compressive Strength of Pastes by electrical Resistivity Method and Maturity Method

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Journal of Wuhan university of technology(Materials Science) 2011年第5期26卷 983-989页

作者：肖莲珍 school of Materials Science and engineering Wuhan Institute of Technology

The compressive strength development of Portland cement pastes was investigated by the electrical resistivity method and the maturity *** experiments were carried out on the cement pastes with different water-cement ratios at different curing *** results show that the application of the maturity method has limitation to obtain the *** is found that both of the compressive strength and the electrical resistivity follow hyperbolic trend for all the *** hyperbolic equation of each mix is obtained to estimate the ultimate resistivity value which can probably be *** relationship between electrical resistivity and compressive strength of the cement pastes is established based on the test results and interpreted by the empirical Archie equation and a strength-porosity *** relationship between the electrical resistivity after temperature correction and the compressive strength was linear and independent of curing temperature and water-cement ratio.

关键词： electrical resistivity cement hydration compressive strength maturity method

Effect of Nucleating Agent on the Crystallization of Tailings Glass Ceramics Prepared by One-time Sintering

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Journal of Wuhan university of technology(Materials Science) 2009年第4期24卷 658-662页

作者：刘军 school of Material Science and engineering Shenyang Jian Zhu University

Glass ceramics was made by the one-time sintering method using the main raw material of iron tailings. On the basis of quaternary system of CaO-MgO-Al2O3-SiO2, using DTA, XRD and SEM, the effects of different nucleating agents and mixing amounts as well as heat treatment on the crystallization of railings glass ceramics were studied. The experimental results show that, nucleating agent and heat treatment are two necessary conditions for one-time sintering preparation of tailings glass ceramics namely, only adding nucleating agent or experiencing heat treatment, the quaternary system can not crystallize. The composite nucleating agent consisting of Cr2O3 and TiO2 can further lead to the crystallization of the CaO-MgO-A1203-SiO2 quaternary system at the lower temperature, with the major phase of diopside. In the range of mass content, 0%-4%, crystal intensity and crystal content grow. But when mass content is more than 4%, the crystal size will become coarser and the crystal distribution will be less regular. Different heat treatment regimes do not change the composition of the crystalline major phase in the glass ceramics crystallization of CaO-MgO-Al2O3-SiO2 system. In the range of 30-60 minutes, with the extension of nucleation and crystallization, crystallization degree enhanced, but if the holding time surpasses 60 minutes, the crystallization is worse.

关键词： nucleating agent one-time sintering tailings glass ceramics crystallization

Experiment and Numerical Simulation on Axial Compressive Performance of Autoclaved Fly Ash Solid Brick Masonry Columns

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Transactions of Tianjin university 2011年第6期17卷 454-460页

作者：徐春一刘明周海鹰 Faculty of Infrastructure engineering Dalian University of Technology school of Civil engineering Shenyang Jianzhu University

To study the influence of slenderness on the axial compressive performance of autoclaved fly ash solid brick masonry columns, compression experiments were conducted on 12 samples of autoclaved fly ash solid brick masonry column and 4 samples of fired clay brick masonry column. The damage patterns and compressive performance were compared and analyzed. The experimental results indicate that the compressive bearing capacity decreases as slenderness increases from 3 to 18, and the compressive bearing capacity of the autoclaved fly ash solid brick masonry columns is lower than that of the fired clay brick masonry columns. The formulae for the axial compressive bearing capacity of autoclaved fly ash solid brick masonry columns were derived based on the experiments. The nonlinear FEA program ANSYS was adopted to simulate the behaviors of masonry columns. By comparing the simulation results and experimental results, it is shown that the simulation results agree well with the experimental ones. The rationality and applicability of the simulation results were verified.

关键词： masonry autoclaved fly ash solid brick compressive bearing capacity slenderness numerical simulation