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基于江苏资源特点的绿色农路建设研究

交通企业管理 2025年第1期40卷 69-71页

作者：顾腾飞苏交科集团股份有限公司

绿色农路建设是践行习近平生态文明思想、深化绿色发展理念、助力美丽中国建设的必然要求,也是支撑交通强国建设、实现行业转型升级的关键举措,需要高度重视农村公路生态保护与修复,不断提高农村公路发展与生态环境的友好程度。目前,绿... 详细信息

绿色农路建设是践行习近平生态文明思想、深化绿色发展理念、助力美丽中国建设的必然要求,也是支撑交通强国建设、实现行业转型升级的关键举措,需要高度重视农村公路生态保护与修复,不断提高农村公路发展与生态环境的友好程度。目前,绿色农路建设尚处于探索阶段,缺乏科学的建设标准规范.

关键词：农村公路绿色农路生态环保节能减排全寿命周期

Application of New Empirical Models Based on Mathematical Statistics in the Through-Flow Analysis

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Journal of Thermal Science 2021年第6期30卷 2087-2098页

作者： fei teng JI Lucheng School of Aerospace Engineering Beijing Institute of TechnologyBeijing 100081China

The through-flow analysis is an important part in the compressor design *** this part,lots of empirical models are used to predict the compressor aerodynamic *** models are all based on the early experimental results of low-load and low-speed compressors;so,they may not be suitable for modern compressor performance *** this study,several empirical models were reviewed,and two new models to estimate the minimum blade profile loss and minimum-loss deviation angle were established using mathematical ***,the original models with poor accuracy were replaced by these two models in through-flow ***,three compressors(Rotor 67,Stage 35,and a 4-stage repeating stage)were simulated using both the original and new *** final results show that the new models have better accuracy in estimating the performance parameters than the original *** indicates that it is feasible to use mathematical statistical methods to establish the empirical models,and this method provides an idea for the improvement of other empirical models in through-flow program.

关键词： through-flow analysis empirical models blade loss deviation regression analysis

Reduced-order proper orthogonal decomposition extrapolating finite volume element format for two-dimensional hyperbolic equations

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Applied Mathematics and Mechanics(English Edition) 2017年第2期38卷 289-310页

作者： Zhendong LUO fei teng School of Mathematics and Physics North China Electric Power University Beijing 102206 China School of Control and Computer Engineering North China Electric Power University Beijing 102206 China

This paper is concerned with establishing a reduced-order extrapolating fi- nite volume element （FVE） format based on proper orthogonal decomposition （POD） for two-dimensional （2D） hyperbolic equations. For this purpose, a semi discrete variational format relative time and a fully discrete FVE format for the 2D hyperbolic equations are built, and a set of snapshots from the very few FVE solutions are extracted on the first very short time interval. Then, the POD basis from the snapshots is formulated, and the reduced-order POD extrapolating FVE format containing very few degrees of freedom but holding sufficiently high accuracy is built. Next, the error estimates of the reduced-order solutions and the algorithm procedure for solving the reduced-order for- mat are furnished. Finally, a numerical example is shown to confirm the correctness of theoretical conclusions. This means that the format is efficient and feasible to solve the 2D hyperbolic equations.

关键词： reduced-order finite volume element (FVE) extrapolating format properorthogonal decomposition (POD) hyperbolic equation error estimate numerical simula-tion

The Defocusing Energy-supercritical NLS in Higher Dimensions

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Acta Mathematica Sinica,English Series 2017年第7期33卷 911-925页

作者： teng fei ZHAO The Graduate School of China Academy of Engineering Physics P.O.Box 2101Belting 100088P.R.China

Abstract We consider the defocusing nonlinear SchrSdinger equations iut ＋△u = lulPu with p being an even integer in dimensions d ≥ 5. We prove that an a priori bound of critical norm implies global well-posedness a... 详细信息

关键词： Nonlinear Schr?dinger equation priori bound scattering

Business cases for energy storage with multiple service provision

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Journal of Modern Power Systems and Clean Energy 2016年第4期4卷 615-625页

作者： fei teng Goran STRBAC Imperial College London South Kensington CampusLondonUK

Energy storage(ES)has been considered as the key source of flexibility to support the integration of renewable *** studies have demonstrated the substantial system cost savings by the deployment of ES,including both investment and operation of generation,transmission and distribution ***,this societal benefit may not be realized if industry actors do not have a viable business case to appropriately capture these multiple value *** this context,this paper investigates the value that ES may deliver to its owner over two specific business cases in a 2030 UK ***,the application of large-scale ES in the wholesale market is *** is demonstrated that the optimal allocation of ES to provide multiple services is the key element for ES to become competitive in the electricity *** the second business case,this paper analyses the value of kilowattscale ES combined with roof photovoltaic(PV)system in the household and community *** study shows that multiple service provision of ES through advanced pricing schemes,for example time-of-use(ToU)tariff and dynamic distribution use of system(DUoS),lead to higher value and the coordination in the community level could further justify the application of domestic ES.

关键词： Energy storage Wind generation Business case Electricity market Multiple service provision

A multi-model assessment of climate change damage in China and the world

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Advances in Climate Change Research 2022年第3期13卷 385-396页

作者： Tian-Peng WANG fei teng Institute of Energy Environment and EconomyTsinghua UniversityBeijing 100084China

Quantifying climate damage is essential to informing rational climate policies,but only a few studies have systematically compared the climate damage estimates made by different models,especially for *** this study,we used three widely applied integrated assessment models-FUND,RICE,and PAGE-to estimate the damage under coupled shared socioeconomic pathways and representative concentration pathways(RCPs).Results show that the costs of climate damage constitute approximately 1.5%and 0.7%of China's GDP and global GDP per 1℃ temperature rise on average,*** can reduce climate risk by lowering the average estimate and worst-case effects of climate *** with business-as-usual emissions(RCP8.5),the 2℃ target will reduce the average estimate of climate damage for China and the world by 93%and 87%,respectively,and by 80%and 84%,respectively,in the worst-case *** analysis of climate damage highlights the inconsistency of sector scope and significant parameter uncertainties in damage modules,requiring further improvement to integrate subfield research advances,particularly for damage related to rising sea levels and cooling energy demand.

关键词： Integrated assessment models Climate damage Shared socioeconomic pathways Representative concentration pathways China

Bounded Evaluation:Querying Big Data with Bounded Resources

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International Journal of Automation and computing 2020年第4期17卷 502-526页

作者： Yang Cao Wen-fei Fan teng-fei Yuan University of Edinburgh Edinburg EH89ABUKUniversity of EdinburghEdinburg EH89ABUK Shenzhen Institute of Computing Sciences Shenzhen UniversityShenzhen 518060China Beijing Advanced Innovation Center for Big Data and Brain Computing Beihang UniversityBeijing 100191China

This work aims to reduce queries on big data to computations on small data,and hence make querying big data possible under bounded resources.A query Q is boundedly evaluable when posed on any big dataset D,there exists a fraction DQ of D such that Q(D)=Q(DQ),and the cost of identifying DQ is independent of the size of *** has been shown that with an auxiliary structure known as access schema,many queries in relational algebra(RA)are boundedly evaluable under the set semantics of *** paper extends the theory of bounded evaluation to RAaggr,i.e.,RA extended with aggregation,under the bag semantics.(1)We extend access schema to bag access schema,to help us identify DQ for RAaggr queries Q.(2)While it is undecidable to determine whether an RAaggr query is boundedly evaluable under a bag access schema,we identify special cases that are decidable and practical.(3)In addition,we develop an effective syntax for bounded RAaggr queries,i.e.,a core subclass of boundedly evaluable RAaggr queries without sacrificing their expressive power.(4)Based on the effective syntax,we provide efficient algorithms to check the bounded evaluability of RAaggr queries and to generate query plans for bounded RAaggr queries.(5)As proof of concept,we extend PostgreSQL to support bounded *** experimentally verify that the extended system improves performance by orders of magnitude.

关键词： Bounded evaluation resource-bounded query processing effective syntax access schema boundedness

Some tests and improvements to the VFISV: Very Fast Inversion of the Stokes Vector for the Helioseismic and Magnetic Imager

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Research in Astronomy and Astrophysics 2014年第11期14卷 1469-1480页

作者： fei teng Yuan-Yong Deng Key Laboratory of Solar Activity National Astronomical ObservatoriesChinese Academy of Sciences

Some experimental tests and improvements to the Very Fast Inversion of the Stokes Vector program, which is designed for the inversion calculation used by the Helioseismic and Magnetic Imager instrument on the Solar Dynamics Observatory, are given. On one hand, the interpolation for calculating the Voigt function is not smooth, which may occasionally cause the iteration process to converge to different minima although they are very close to initial values. This problem can be solved by a smoother interpolation. On the other hand, in order to improve the performance of this program, we have tried to abandon the randomly-jump-out strategy and set the initial value properly to avoid non-global minima. The resulting method costs only 1//4 of the computational time, and will be very competitive when the users are only interested in the vectorial magnetic fields and the velocities along the line of sight.

关键词： Sun magnetic fields -- methods numerical -- techniques polarimetric

A fast Stokes inversion technique based on quadratic regression

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Research in Astronomy and Astrophysics 2016年第5期16卷 7-16页

作者： fei teng Yuan-Yong Deng Key Laboratory of Solar Activity National Astronomical Observatories Chinese Academy of Sciences

Stokes inversion calculation is a key process in resolving polarization information on radiation from the Sun and obtaining the associated vector magnetic fields. Even in the cases of simple local thermo- dynamic equilibrium （LTE） and where the Milne-Eddington approximation is valid, the inversion problem may not be easy to solve. The initial values for the iterations are important in handling the case with mul- tiple minima. In this paper, we develop a fast inversion technique without iterations. The time taken for computation is only 1/100 the time that the iterative algorithm takes. In addition, it can provide available initial values even in cases with lower spectral resolutions. This strategy is useful for a filter-type Stokes spectrograph, such as SDO/HMI and the developed two-dimensional real-time spectrograph （2DS）.

关键词： Sun: magnetic fields -- methods: statistical -- methods: data analysis -- techniques: polari-metric