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Journal of wuhan university of technology(Materials science) 2011年第4期26卷 600-605页

作者：史晓亮 school of Mechanical and Electronic Engineering Wuhan University of Technology State Key Laboratory of Advanced technology for Materials Synthesis & Processing Wuhan University of Technology

High purity anatase nano-TiO2 powders with high photocatalytic activity were prepared by a hydrothermal synthesis method. X-ray diffraction （XRD）, field emission transmission electron microscopy （FETEM）, ultraviolet-visible （UV-Vis） light absorption spectrum and photoluminescence （PL） spectrum were adopted to characterize the catalyst. Effects of temperature, time and sol concentration of hydrothermal synthesis on particle size and phases were investigated. Photocatalytic activities in the degradation of Rhodamine B Dye were studied. The experimental results indicated that photocatalytic activity of the nano-TiO2 powers was much higher than that of P25 （Degussa）.

关键词： TiO2 hydrothermal synthesis photocatalytic activity high purity anatase

Magnesia Modification of Alkali-Activated Slag Fly Ash Cement

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Journal of wuhan university of technology(Materials science) 2011年第1期26卷 121-125页

作者：沈卫国 Key Laboratory of Silicate Materials science and Engineering of Ministry of Education Wuhan University of Technology school of Materials science and Engineering Wuhan University of Technology

A new type of magnesia modification alkali-activated cement was prepared, the strength, setting time, shrinkage ratio and cracking behavior, as well as the composition and structure of the hydration product were investigated. The results indicate that the setting time of this cement is similar to that of the ordinary commercial cements; its strength reaches the standard of 42.5 degree cement, its cracking resistance has been remarkably improved because of the micro-aggregate effect of fly ash and shrinkage compensating of magnesia.

关键词： alkali-activated cement crack magnesia volume stability hydration

Intelligent Forecasting of Sintered Ore’s Chemical Components Based on SVM

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Journal of wuhan university of technology(Materials science) 2011年第3期26卷 583-587页

作者：钟珞王清波 school of Computer science and technology Wuhan University of Technology

Using object mathematical model of traditional control theory can not solve the forecasting problem of the chemical components of sintered *** order to control complicated chemical components in the manufacturing process of sintered ore,some key techniques for intelligent forecasting of the chemical components of sintered ore are studied in this paper.A new intelligent forecasting system based on SVM is proposed and *** results show that the accuracy of predictive value of every component is more than 90%.The application of our system in related companies is for more than one year and has shown satisfactory results.

关键词： sintered ore support vector machine intelligent forecasting nonlinear regression optimized control

A PRICE-SETTING NEWSVENDOR MODEL UNDER CVAR DECISION CRITERION WITH EMERGENCY PROCUREMENT

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Journal of Systems science and Systems Engineering 2010年第1期19卷 85-104页

作者： Minghui XU school of Economics and Management,wuhan university,wuhan 430072,china school of Economics and Management Wuhan University Wuhan China

In this paper, we consider a newsvendor model in which a risk-averse manager faces a stochastic price-dependent demand in either an additive or a multiplicative form. An emergency purchase option is allowed after the realization of demand to satisfy the units that are short. By adopting Conditional value-at-risk （CVaR） as the decision criterion, we aim to investigate the optimal pricing and ordering decisions, and the effects of parameter changes in such a setting. We provide sufficient conditions for the uniqueness of the optimal policy for both demand models. We perforl~, comparative statics analysis to show how the optimal pricing and ordering decision behaves when changing parameters. We also compare our results with those of the newsvendor with a general utility function and with CVaR criterion under lost sales assumption. Our key results include：（i） For both demand models, the optimal selling price is decreasing in risk aversion. Hence, the optimal price of a risk-averse newsvendor is not greater than the optimal price of a risk-neutral newsvendor. （it） In contrary to the lost sales case, for the multiplicative demand model, the optimal order quantity may not be monotonic in risk aversion. Consequently, the optimal risk-averse order quantity may be lower or higher than the optimal risk- neutral counterpart. （iii） For the additive model, the optimal order quantity is strictly increasing in the emergency purchase price, while for the multiplicative model the optimal order quantity has no such a monotonic property. Some numerical examples are conducted to verify our claims and gain more insights about the risk-averse decision-making behaviors.

关键词： Newsvendor model inventory pricing risk aversion conditional value-at-risk

Quasi-physical global optimization method for solving the equal circle packing problem

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science china(Information sciences) 2011年第7期54卷 1333-1339页

作者： HUANG WenQi & YE Tao school of Computer science and technology,Huazhong university of science and technology,wuhan 430074,china 1. school of Computer science and technology Huazhong University of Science and Technology Wuhan 430074 China

The equal circle packing problem is a well-known challenge in *** is also a natural,clear and fair test system for global *** paper presents a quasi-physical global optimization algorithm for solving the equal circle packing *** algorithm simulates two kinds of movements of N elastic disks: smooth movement driven by elastic pressures and violent movement driven by strong repulsive forces and attractive *** smooth movement makes the disks reach a locally optimal configuration,while the violent movement makes them jump out of the local optimum trap and reach a more promising *** algorithm is tested on the widely studied instances of N = 1,2,...,*** find better packings than the reported best-known ones on 37 instances and reproduce the best-known results on the remaining 113 instances.

关键词： equal circle packing global optimization quasi-physical method heuristic

The Development and Research on the Coordinate Control Strategy Between Turbine and Boiler in Fossil Power Plant

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武汉理工大学学报 2006年第S1期28卷 363-366页

作者： WEI Shuangying (Management school,wuhan university of technology,wuhan 430070,china) Management school Wuhan University of TechnologyWuhan 430070China

Based on the research on domestic and international automatic technical development in fossil power plant,the paper analyses the recent situation of the coordinate control system between turbine and boiler of domestic fossil Power Plant,provides the development thought of coordinate control system between turbine and boiler,and describes the application prospect in control system of fossil power plant combining with the application experience.

关键词： fossil power plant coordinate control system between turbine and boiler development and research

Mechanism and Optimal Application of Chemical Additives for Accelerating Early Strength of Lime-flyash Stabilized Soils

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Journal of wuhan university of technology(Materials science) 2005年第3期20卷 110-112页

作者：姜增国 school of Civil and Architecture Wuhan University of Technology

To accelerate the early strength of lime-flyush stabilized soil for extending its further uses in highway and shortening highway constraction time, five kinds of chemical odditives were chosen on the basis of mechanism analysis of accelerating early strength in highway as a semi-rigid base materhd, and a series of experiments about the effect of differeat kinds of additives and quantity on the early strength of the stabilized soll were tested. The results show that chemical additives can efftciently improve the early strength of lime-flyush stabilized soil both the 7 d and 28d, and the optimum quantity for above chemical additive is 1.5%-2.5% approximately. Some suggestions for the practical construction were also proposed.

关键词： lime-flyash stabilized soil chemical additives early strength

Weak martingale Hardy spaces and weak atomic decompositions

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science china Mathematics 2006年第7期49卷 912-921页

作者： HOU Youliang & REN Yanbo school of Mathematics and Statistics, wuhan university, wuhan 430072, china Department of Mathematics & Physics, Henan university of science and technology, Luoyang 471003, china 1. school of Mathematics and Statistics Wuhan University Wuhan 430072 China 2. Department of Mathematics & Physics Henan University of Science and Technology Luoyang 471003 China

In this paper we define some weak martingale Hardy spaces and three kinds of weak atoms. They are the counterparts of martingale Hardy spaces and atoms in the classical martingale Hp-theory. And then three atomic decomposition theorems for martingales in weak martingale Hardy spaces are proved. With the help of the weak atomic decompositions of martingale, a sufficient condition for a sublinear operator defined on the weak martingale Hardy spaces to be bounded is given. Using the sufficient condition, we obtain a series of martingale inequalities with respect to the weak Lp-norm, the inequalities of weak (p ,p)-type and some continuous imbedding relationships between various weak martingale Hardy spaces. These inequalities are the weak versions of the basic inequalities in the classical martingale Hp-theory.

关键词： martingale, weak Hardy space, weak atom, atomic decomposition.

Mechanical Properties of Layered Steel Fiber and Hybrid Fiber Reinforced Concrete

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Journal of wuhan university of technology(Materials science) 2008年第5期23卷 733-736页

作者：卢哲安 Hubei Key Laboratory of Roadway Bridge and Structure Engineering Wuhan University of Technology

To explore a new structure form of fiber reinforced concrete, namely, the layered steel fiber and layered hybrid fiber reinforced concrete （LSFRC and LHFRC）, the mechanical properties of LSFRC and LHFRC, such as compressive strength, tensile strength, flexural strength, fatigue and durability were focused on. The experimental results show that LSFRC and LHFRC can improve the flexural strength of concrete by 20%-50%. In the aspect of improving the flexural strength of concrete, adulterant rate has more obvious effect than length/diameter ratio. Double logarithmic fatigue equation considered liveability was founded. The impermeability of LHFRC is superior to LSFRC and plain concrete （C）. However, the porosity of LHFRC is lower than LSFRC and C. The shrinkage of LHFRC at every age is obviously lower than C. The antifreeze durability of LHFRC is also better than C.

关键词： layered steel fiber reinforced concrete mechanical properties layer hybrid fiber reinforced concrete

Multispectral image fusion method based on intensity-hue-saturation and nonsubsampled three-channels non-separable wavelets

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Chinese Optics Letters 2010年第4期8卷 384-387页

作者：刘斌刘维杰彭嘉雄 school of Mathematics and Computer science Hubei university Computer school Wuhan University Institute of Image Recognition and Artificial Intelligence Huazhong University of Science and Technology

A new multispectral image fusion method based on intensity-hue-saturation（IHS） transform and threechannel non-separable wavelets whose dilation matrix is[2,1;1,1]is *** multi-resolution decompositions of the intensity of multispectral image and panchromatic image are performed in nonsubsampled mode using the three-channel non-separable wavelet filter *** approximation images and the detail images of the multi-resolution pyramids are *** experimental results show that this method has good visual *** performance outperforms the IHS fusion *** discrete wavelet transform （DWT） fusion method,and the IHS-DWT fusion method in preserving spectral quality and high spatial resolution information.

关键词： Decomposition Discrete wavelet transforms Filter banks Visual communication