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AN AFFINE SCALING DERIVATIVE-FREE TRUST REGION METHOD WITH INTERIOR BACKTRACKING TECHNIQUE FOR BOUNDED-CONSTRAINED NONLINEAR PROGRAMMING

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Journal of Systems Science & Complexity 2014年第3期27卷 537-564页

作者： GAO jing zhu Detong Department of Mathematics Shanghai Normal University

This paper proposes an arlene scaling derivative-free trust region method with interior backtracking technique for bounded-constrained nonlinear programming. This method is designed to get a stationary point for such a problem with polynomial interpolation models instead of the objective function in trust region subproblem. Combined with both trust region strategy and line search technique, at each iteration, the affine scaling derivative-free trust region subproblem generates a backtracking direction in order to obtain a new accepted interior feasible step. Global convergence and fast local convergence properties are established under some reasonable conditions. Some numerical results are also given to show the effectiveness of the proposed algorithm.

关键词： Affine scaling backtracking technique box constrains derivative-free optimization non-linear programming trust region method.

Improving the Seasonal Forecast of Summer Precipitation in China Using a Dynamical-Statistical Approach

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Atmospheric and Oceanic Science Letters 2010年第2期3卷 100-105页

作者： JIA Xiao-jing zhu Pei-jun Department of Earth Sciences Zhejiang University Hangzhou Zhejiang 310027 China

A dynamical-statistical post-processing approach is applied to seasonal precipitation forecasts in China during the *** data are ensemble-mean seasonal forecasts in summer (june August) from four atmospheric general circulation models (GCMs) in the second phase of the Canadian Historical Forecasting Project (HFP2) from 1969 to *** dynamical-statistical approach is designed based on the relationship between the 500 geopotential height (Z500) forecast and the observed sea surface temperature (SST) to calibrate the precipitation *** results show that the post-processing can improve summer precipitation forecasts for many areas in *** examination shows that this post-processing approach is very effective in reducing the model-dependent part of the errors,which are associated with *** possible mechanisms behind the forecast's improvements are investigated.

关键词： precipitation forecasts ensemble forecasts dynamical-statistical approach

Synergistically enhanced thermoelectric properties of Bi_(2)S_(3) bulk materials via Cu interstitial doping and BiCl_(3) alloying

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Rare Metals 2022年第3期41卷 931-941页

作者： jun Guo Zi-Yuan Wang Yu-Ke zhu Lin Chen jing Feng Zhen-Hua Ge Faculty of Materials Science and Engineering Kunming University of Science and TechnologyKunming 650093China

Bi_(2)S_(3)is composed of inexpensive and environ-mental friendliness elements,which has received extensive interests and been investigated as a promising mid-tempera-ture thermoelectric material for *** pure Bi_(2)S_(3)pos-sesses a high Seebeck coefficient and low thermal conductivity,its low electrical conductivity leads to a lowfigure of merit(ZT)*** this work,Bi_(2)S_(3)fabricated by solid-state melting combined with spark plasma sintering can significantly enhance the thermoelectric performance via introducing small amounts of Cu and BiCl_(3).Cu interstitial doping and Cl substitution on S site result in a large increase in electrical ***,the enhanced phonon scattering is derived from the point defects caused by element doping,the grain boundaries,and the small amount of sec-ondary phase,which leads to the low thermal ***,a high ZT value of 0.7 is obtained at 773 K and reaches a large average ZT of 0.36 in the temperature range from room temperature(RT)to 773 K for the Cu-interstitial-doped and BiCl_(3)-alloyed(Cu_(0.01)Bi_(2)S_(3)+0.175 mol%BiCl_(3))***,the mechanical properties of the Cu_(0.01)Bi_(2)S_(3)+0.175 mol%BiCl_(3)sample are lower than those of other Bi_(2)S_(3)samples,which stem from the weak chemical bonding strength.

关键词： Bismuth sulfide Cu–Cl co-doping Electrical conductivity Mechanical properties

High thermoelectric properties realized in earth abundant Bi_(2)S_(3) bulk materials via Se and Cl co-doping in solution synthesis process

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Journal of Materials Science & Technology 2022年第5期100卷 51-58页

作者： jun Guo Yu-Ke zhu Lin Chen Zi-Yuan Wang Zhen-Hua Ge jing Feng Faculty of Materials Science and Engineering Kunming University of Science and TechnologyKunming 650093China

Bi_(2)S_(3)-based alloys are considered promising thermoelectric materials due to their large Seebeck coefficient and low lattice thermal ***,low electrical conductivity usually leads to poor electrical transport properties,which seriously restricts their further application in thermoelectric refrigeration and/or power *** this work,Bi_(2)S_(3) with high electrical transport properties is synthesized hydrothermally via Se and Cl *** maximum electrical conductivity value of 483 S cm^(-1) was obtained for the Bi_(2)S_(2.4)Se_(0.4)Cl_(0.20) sample at room *** significant improvement of electrical conductivity gives rise to a high average power factor of 411μW m^(-1) K^(-2) during the measuring temperature range and a peak value of 456μW m^(-1) K^(-2) at 673 *** from the largely improved electrical transport properties,a superior ZT value of approximately 0.66 and *** 0.36 were obtained for Bi_(2)S_(2.4)Se_(0.4)Cl_(0.20),and the theoretically calculated conversion efficiency reached 5.7%.The results indicate that Bi_(2)S_(3) is a promising candidate for thermoelectric applications at medium temperatures.

关键词： Bismuth sulfide Electrical conductivity Doping Thermal conductivity

Increased Hydrogen-bonding of Poly(m-phenylene isophthalamide) (PMIA) with Sulfonate Moiety for High-performance Easily Dyeable Fiber

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Chinese Journal of Polymer Science 2020年第11期38卷 1230-1238,I0008页

作者： Na Li Xing-Ke Zhang jun-Rong Yu Yan Wang jing zhu Zu-Ming Hu State Key Laboratory for Modification of Chemical Fibers and Polymer Materials College of Materials Science and EngineeringDonghua UniversityShanghai 201620China

The demand for high thermal stability and high strength agents is growing steadily as a result of their increasing application in advanced materials.A series of sulfonated poly(m-phenyleneisophthalamide)(SPMIA)copolymers with superior thermal stability and good mechanical properties have been prepared via low temperature polycondensation *** the structures of 5PMA copolymers with different content quantities of 2,4-diaminobenzenesulfonic acid(2,4-DABSA)were confimed by Fourier transform infrared(FTiR).Besides,their superior thermal properties were systematically investigated by differential canning calorimetry DSC),thermalgravimetreic analysis(TGA),and dynamic mechanical analysis(DMA).SPMA fbers were obtained by wet spinning using the resultant SPMIAsolutions.n addition,the obtained SPMIA fibers were proved to combine enhanced mechanical properties and unprecedented ***,the SPMlA iber with great mechanical property,thermal stability,and dyeability shows great potential in easily dyeing high-performance protective fibers.

关键词： Sulfonated polyim-phenyleneisophthalamide) Copolymer Sulfonic acid group High-Performance fiber Eaily dyeable fiber

Influences of Technological Parameters on Smelting-separation Process for Metallized Pellets of Vanadium-bearing Titanomagnetite Concentrates

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Journal of Iron and Steel Research International 2016年第7期23卷 655-660页

作者： En-hui WU Rong zhu Shao-li YANG Lan MA jun LI jing HOU School of Metallurgical and Ecological Engineering University of Science and Technology Beijing Innovation and Technology Center of Panxi Panzhihua University

The smelting-separation process for metallized pellets of vanadium-bearing titanomagnetite concentrates was *** influences of smelting temperature,smelting time,and the basicity of the metallized pellet on vanadium and iron recovery were *** characteristics of titanium slag were analyzed using X-ray diffraction,energy dispersive spectroscopy,and mineralographic microscopic *** results demonstrate that appropriate increases in smelting temperature and smelting time can improve the vanadium and iron recovery from metallized pellets and are beneficial for the slag-iron *** increasing the basicity of the metallized pellet can considerably improve the vanadium and iron recovery,the TiO;grade of titanium slag was *** the optimal conditions,90.17% of vanadium and 92.98% of iron in the metallized pellet were recovered,and the TiO;grade of titanium slag was 55.01%.It was found that anosovite,augite,spinel,glassiness,and metallic iron were the main mineral phases of the titanium slag.

关键词： metallized pellet smelting separation titanium slag vanadium vanadium-bearing titanomagnetite concentrate

Synthesis and Characterization of Easily Colored Meta-aramid Copolymer Containing Ether Bonds

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Chinese Journal of Polymer Science 2019年第3期37卷 227-234页

This work described the preparation of easily colored meta-aramid(PMIA) copolymers from m-phenylenediamine(MPD),isophthaloyl dichloride(IPC), and 3,4′-oxydianiline(3,4′-ODA) via solution polycondensation in N,N-dimethylacetamide(DMAc). The novel co-PMIAs were obtained in relatively high inherent viscosities ranging from 1.32 dL/g to 2.53 dL/g, which could be easily cast into flexible films with high transparence or spun into fibers. All the newly synthesized copolymers possessed excellent thermal stabilities even better than that of commercial PMIA, with 5% weight loss temperatures higher than 430 °C in nitrogen measured by TGA and glass transition temperature of 267–277 °C measured by DSC. The cast films exhibited good mechanical properties with a tensile strength up to107 MPa and a tensile modulus up to 2.2 GPa. The resultant PMIAs also showed good solubility and better dye ability for cationic dyes.

关键词： Copolymerized meta-aramid Solution polycondensation Dyeability

Mechanical behavior of Ti-6Al-4V lattice-walled tubes under uniaxial compression

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Defence Technology（防务技术） 2022年第7期18卷 1124-1138页

作者： Gen-zhu Feng jing Wang Xin-yuan Li Li-jun Xiao Wei-dong Song State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing100081China Earthquake Engineering Research Center China Institute of Water Resources and Hydropower ResearchBeijing100048PR China Beijing Research Institute of Automation for Machinery Industry Co. LtdBeijing100120China

The compression behavior of the lattice-walled tubes under variable strain rates are investigated by numerical simulation,and the stress-strain relationship of the structure under quasi-static loading is theoretically *** finite element software LS-DYNA is used to simulate the structure established by the beam element,and the critical impact velocity is obtained when the structure collapses layer by *** to the plastic hinge theory and considering the combined action of the beam's bending moment and axial force in the structure,the stress-strain relationship of the structure under quasi-static loading is derived and compared with the experimental *** numerical simulation results reveal that the structure of the single-layer gradient tube(SGC)does not undergo shear deformation under quasi-static and low-speed *** critical speed of the gradient square tube(GS)is higher than that of a cylindrical *** theoretical model can correctly reflect the mechanical response of the structure under uniaxial compression.

关键词： Lattice-walled tubes Plastic hinge theory Numerical simulation Critical velocity

A hybrid model for dissolved oxygen prediction in aquaculture based on multi-scale features

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Information Processing in Agriculture 2018年第1期5卷 11-20页

作者： Chen Li Zhenbo Li jing Wu Ling zhu jun Yue College of Information and Electrical Engineering China Agricultural UniversityBeijing 100083China College of Information and Electrical Engineering Ludong UniversityYantaiShandong 264025China

To increase prediction accuracy of dissolved oxygen(DO)in aquaculture,a hybrid model based on multi-scale features using ensemble empirical mode decomposition(EEMD)is ***,original DO datasets are decomposed by EEMD and we get several ***,these components are used to reconstruct four terms including high frequency term,intermediate frequency term,low frequency term and trend ***,according to the characteristics of high and intermediate frequency terms,which fluctuate violently,the least squares support vector machine(LSSVR)is used to predict the two *** fluctuation of low frequency term is gentle and periodic,so it can be modeled by BP neural network with an optimal mind evolutionary computation(MEC-BP).Then,the trend term is predicted using grey model(GM)because it is nearly ***,the prediction values of DO datasets are calculated by the sum of the forecasting values of all *** experimental results demonstrate that our hybrid model outperforms EEMD-ELM(extreme learning machine based on EEMD),EEMD-BP and MEC-BP models based on the mean absolute error(MAE),mean absolute percentage error(MAPE),mean square error(MSE)and root mean square error(RMSE).Our hybrid model is proven to be an effective approach to predict aquaculture DO.

关键词： DO prediction Aquaculture Hybrid model