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Thermodynamic Performance Analysis of E/F/H-Class Gas Turbine Combined Cycle with Exhaust Gas Recirculation and Inlet/Variable Guide Vane Adjustment under Part-Load Conditions

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Journal of Thermal Science 2024年第1期33卷 348-367页

作者： LI Keying CHI jinling WANG Bo ZHANG Shijie Key Lab of Advanced Energy and Power Institute of Engineering ThermophysicsChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China School of Mechanical Electronic&Information Engineering China University of Mining&Technology-BeijingBeijing 100083China

Exhaust gas recirculation control(EGRC),an inlet air heating technology,can be utilized in combination with inlet/variable guide vane control(IGV/VGVC) and fuel flow control(FFC) to regulate the load,thereby effectively improving the part-load(i.e.,off-design) performance of the gas turbine combined cycle(GTCC).In this study,the E-,F-,and H-Class EGR-GTCC design and off-design system models were established and validated to perform a comparative analysis of the part-load performance under the EGR-IGV-FFC and conventional IGV-FFC strategies in the E/F/H-Class *** show that EGR-IGV-FFC has considerable potential for the part-load performance enhancement and can show a higher combined cycle efficiency than IGV-FFC in the E-,F-,and H-Class ***,the part-load performance improvement in the corresponding GTCC was weakened for the higher class of the gas turbine because of the narrower load range of EGR action and the deterioration of the gas turbine ***,EGR-IGV-FFC was inferior to IGV-FFC in improving the performance at loads below 50% for the H-Class *** results obtained in this paper could help guide the application of EGR-IGV-FFC to enhance the part-load performance of various classes of GTCC systems.

关键词： E/F/H-Class gas turbine combined cycle performance improvement part-load conditions exhaust gas recirculation inlet/variable guide vane

A Subdivision-Based Combined Shape and Topology Optimization in Acoustics

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Computer Modeling in Engineering & Sciences 2024年第4期139卷 847-872页

作者： Chuang Lu Leilei Chen jinling Luo Haibo Chen CAS Key Laboratory of Mechanical Behavior and Design of Materials Department of Modern MechanicsUniversity of Science and Technology of ChinaHefei230027China College of Intelligent Construction Wuchang University of TechnologyWuhan430223China Henan International Joint Laboratory of Structural Mechanics and Computational Simulation School of Architecture and EngineeringHuanghuai UniversityZhumadian463000China Beijing Aerospace technology institute Beijing100074China

We propose a combined shape and topology optimization approach in this research for 3D acoustics by using the isogeometric boundary element method with subdivision *** existing structural optimization methods mainly contain shape and topology schemes,with the former changing the surface geometric profile of the structure and the latter changing thematerial distribution topology or hole topology of the *** the present acoustic performance optimization,the coordinates of the control points in the subdivision surfaces fine mesh are selected as the shape design parameters of the structure,the artificial density of the sound absorbing material covered on the structure surface is set as the topology design parameter,and the combined topology and shape optimization approach is established through the sound field analysis of the subdivision surfaces boundary element method as a *** topology and shape sensitivities of the approach are calculated using the adjoint variable method,which ensures the efficiency of the *** geometric jaggedness and material distribution discontinuities that appear in the optimization process are overcome to a certain degree by the multiresolution method and solid isotropic material with *** examples are given to validate the effectiveness of the presented optimization approach.

关键词： Subdivision surfaces boundary element method topology optimization shape optimization combined optimization

广东深圳长圳公共租赁住房新型建造技术集成项目

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建筑实践 2024年第3期 104-111页

作者： china Construction Science technology Group Co., Ltd. Shenzhen general institute of Architectural Design and Research Co., Ltd. 中建科技集团有限公司深圳市建筑设计研究总院有限公司

长圳公共住房及其附属工程项目（以下简称长圳项目）位于深圳市光明区,是深圳市规模最大的装配式公共住房项目和深圳市建设管理模式改革创新的试点项目。项目总投资58亿元,地上建筑24栋,总建筑面积约115万m2,其中:住宅建筑面积81万m2,...

长圳公共住房及其附属工程项目（以下简称长圳项目）位于深圳市光明区,是深圳市规模最大的装配式公共住房项目和深圳市建设管理模式改革创新的试点项目。项目总投资58亿元,地上建筑24栋,总建筑面积约115万m2,其中:住宅建筑面积81万m2,商业建筑6.5万m2,公共配套设施3.2万m2,多层建筑高度10—24m,高层建筑高度100—150m,提供近万套人才安居住房。

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A new sequential learning algorithm for RBF neural networks

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Science china(Technological Sciences) 2004年第4期47卷 447-460页

作者： YANG Ge1, LV Jianhong1 & LIU Zhiyuan2 1. department of Power Engineering, Southeast University, nanjing 210096, china 2. department of Power Engineering, nanjing institute of technology, nanjing 210013, china department of Power Engineering Southeast University Nanjing China department of Power Engineering Nanjing Institute of Technology Nanjing China

Due to their inherent imperfections, it is hard to use the static neural networks for nonlinear time-varying process modeling and prediction, and the minimal resource allocation network (MRAN) is difficult to be realized for its too many regulation parameters. A new sequential learning algorithm for radial basis function (RBF) neural networks based on local projection named Local Projection Network (LPN) is proposed in this paper. The results of validation for several benchmark problems with the new algorithm show that the presented LPN not only has the same level as M-RAN in network size and precision of the outputs, but also has fewer regulation parameters and is more predictable.

关键词： radial basis functions, local projection network, minimal resource allocation network, learning algorithm.

One-step estimation for varying coefficient models

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Science china Mathematics 2005年第2期48卷 198-213页

作者： TANG Qingguo & WANG Jinde department of Mathematics, nanjing University, nanjing 210093, china institute of Sciences, PLA University of Science and technology, nanjing 210007, china department of Mathematics Nanjing University Nanjing China institute of Sciences PLA University of Science and Technology Nanjing China

A one-step method is proposed to estimate the unknown functions in the varying coefficient models, in which the unknown functions admit different degrees of smoothness. In this method polynomials of different orders are used to approximate unknown functions with different degrees of smoothness. As only one minimization operation is employed, the required computation burden is much less than that required by the existing two-step estimation method. It is shown that the one-step estimators also achieve the optimal convergence rate. Moreover this property is obtained under conditions milder than that imposed in the two-step estimation method. More importantly, as only one minimization operation is employed, the full asymptotic properties, not only the asymptotic bias and variance, but also the asymptotic distributions of the estimators can be derived. The asymptotic distribution results will play a key role for making statistical inference.

关键词： varying coefficient model, one-step estimation, asymptotic distribution, optimal convergence rate.

Global dimension and left derived functors of Hom

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Science china Mathematics 2007年第6期50卷 887-898页

作者： Li-xin MAO & Nan-qing DING institute of Mathematics, nanjing institute of technology, nanjing 211167, china department of Mathematics, nanjing University, nanjing 210093, china institute of Mathematics Nanjing Institute of Technology Nanjing China department of Mathematics Nanjing University Nanjing China

It is well known that the right global dimension of a ring R is usually computed by the right derived functors of Hom and the left projective resolutions of right R-modules. In this paper, for a left coherent and right perfect ring R, we characterize the right global dimension of R, from another point of view, using the left derived functors of Hom and the right projective resolutions of right R-modules. It is shown that rD(R) ? n (n ? 2) if and only if the gl right Proj-dim M R ? n?2 if and only if Ext n?1(N,M) = 0 for all right R-modules N and M if and only if every (n?2)th Projcosyzygy of a right R-module has a projective envelope with the unique mapping property. It is also proved that rD(R) ? n (n ? 1) if and only if every (n?1)th Proj-cosyzygy of a right R-module has an epic projective envelope if and only if every nth Proj-cosyzygy of a right R-module is projective. As corollaries, the right hereditary rings and the rings R with rD(R) ? 2 are characterized.

关键词： global dimension projective resolution envelope 16E10 16E30 16E05

Highly dispersive tetrahedral vanadium species on pure silica ZSM-12 zeolite boosting the selective oxidation of cyclohexane into cyclohexanone

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Science china Chemistry 2024年第7期67卷 2206-2214页

作者： Menglin Xie Ting Li Chao Wu Xiaoling Liu jinling Ni Siqin Yao Yu Zhou Shibo Xi Jun Wang State Key Laboratory of Materials-Oriented Chemical Engineering College of Chemical EngineeringNanjing Tech UniversityNanjing 211816China institute of Sustainability for Chemicals Energy and Environment(ISCE2)Agency for ScienceTechnology and Research(A*STAR)Singapore 627833Republic of Singapore College of Materials Science and Engineering Sichuan UniversityChengdu 610065China

The selective oxidation of cyclohexane is a promising green route for the production of KA oil(cyclohexanol and cyclohexanone),but remains a huge challenge to design high-performing heterogeneous catalysts under mild ***,a pure silica ZSM-12(MTW topology)zeolite was applied as the support to immobilize highly dispersive tetrahedrally coordinated vanadium(V)species and the constructed catalyst 1%V/SZ-12 exhibited high efficiency in the fast and selective oxidation of cyclohexane into cyclohexanone with H_(2)O_(2).The reaction completed within 30 s,affording the selectivity of 99%towards cyclohexanone and the extremely high turnover frequency(TOF)of 5,891 h^(-1).1%V/SZ-12 was facilely reused with stable activity and feasibly extended to the oxidation of various cyclohexane *** one-dimensional 12-membered ring microchannels contributed to the formation and accessibility of tetrahedrally coordinated high valent V5+species as the robust active centers,which activated H_(2)O_(2) to generate V–O–O·,the active oxygen species for the electrophilic attack on cyclohexane to produce cyclohexanone as the sole product.

关键词： zeolite metal doping cyclohexane oxidation heterogeneous catalysis

Reducing component estimation for varying coefficient models with longitudinal data

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Science china Mathematics 2008年第2期51卷 250-272页

作者： TANG QingGuo~(1,2+) WANG JinDe~2 1 institute of Sciences,People’s Liberation Army University of Science and technology,nanjing 210007,china 2 department of Mathematics,nanjing University,nanjing 210093,china institute of Sciences People’s Liberation Army University of Science and Technology Nanjing China department of Mathematics Nanjing University Nanjing China

Varying-coefficient models with longitudinal observations are very useful in epidemiology and some other practical *** this paper,a reducing component procedure is proposed for es- timating the unknown functions and their derivatives in very general models,in which the unknown coefficient functions admit different or the same degrees of smoothness and the covariates can be time- *** asymptotic properties of the estimators,such as consistency,rate of convergence and asymptotic distribution,are *** asymptotic results show that the asymptotic variance of the reducing component estimators is smaller than that of the existing estimators when the coefficient functions admit different degrees of *** sample properties of our procedures are studied through Monte Carlo simulations.

关键词： varying coefficient model longitudinal data nonparametric estimation reducing component estimators asymptotic normality 62G07

Quantitative Evaluation for Drawability of Sheet Metal

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Journal of Materials Science & technology 2005年第5期21卷 763-766页

作者： Zhiqing XIONG and Xuemei YANGdepartment of Mechanical Engineering, nanjing institute of technology, nanjing 210013, china department of Mechanical Engineering Nanjing Institute of Technology Nanjing 210013 China

The theoretical evaluating method is given for the drawability of the sheet with normal anisotropy. The general solution on the cracking load of deep-drawing is deduced, which is based on three kinds of hardening curve of materials most in use. The distributions of stress and strain in the deformed region and the drawing force are obtained by the numerical method. The limiting drawing ratio is calculated through computer-aided simulating test. The experiments of deep-drawing to four kinds of sheet metals express that the relative errors between the predictive and the experimental results about the cracking load and the limiting drawing ratio are within 5%. The drawability of common sheet metals can be quantitatively evaluated in precise terms by means of the theory and the method advanced in this paper.

关键词： Sheet forming Deep-drawing Formability Drawability