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A discussion on technologies for improving the operational speed of high-speed railway networks

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Transportation Safety and Environment 2019年第1期1卷 22-36页

作者： Chun-fang lu China Railway society 100844 BeijingChina

China’s high-speed railway network has already achieved speeds of 350 km/h;however,this could be further increased to 400 km/*** considering the development status and technical level of the high-speed railway system in China,this study indicates that there are four key technologies involved in improving its operational speed:the track,the electrical moving unit,the control system and the traction power *** an experimental analysis,an evaluation index for the high-speed railway is then constructed based on four aspects:safety,comfort,intelligence and environmental *** this system,the rationality of the high-speed railway speed-improvement plan can be scientifically *** results are of practical significance to the Chinese railway administration,as they can be used to formulate specific plans to increase rail speeds,and therefore promote the rapid development of the high-speed railway network in China.

关键词： railway technology high-speed railway railway speed improvement

Development and application of a GIS-based artificial neural network system for water quality prediction: a case study at the Lake Champlain area

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Journal of Oceanology and Limnology 2020年第6期38卷 1835-1845页

作者： lu fang ZHANG Haoqing LIU Wenquan Shandong Provincial Key Laboratory of Marine Environment and Geological Engineering Ocean University of ChinaQingdao 266100China Laboratory for Marine Geology Qingdao National Laboratory for Marine Science and TechnologyQingdao 266000China Key Laboratory of Marine Environment and Ecology Ministry of EducationQingdao 266100China Key Laboratory of Marine Sedimentology and Environmental Geology First Institute of OceanographyMinistry of Natural Resources(MNR)Qingdao 266061China

Artificial Neural Network(ANN)models have been extensively applied in the prediction of water resource variables,and Geographical Information System(GIS)includes powerful functions to visualize spatial *** order to provide an efficient tool for environmental assessment and management that combines the advantages of these two modules,a GIS-based ANN water quality prediction system was developed in the present *** ANN module and ArcGIS Engine module,along with a dynamic database,were imbedded in the system,which integrates water quality prediction via the ANN model and spatial presentation of the model *** structure of the ANN model could be modified through the graphical user interface to optimize the model *** developed system was applied to a real case study for the prediction of the total phosphorus concentration in the Lake Champlain *** prediction results were verified with the monitoring data,and the performance of the developed model was further evaluated through graphical techniques and quantitative statistical ***,the developed system provided satisfactory prediction results,and spatial distribution maps of the predicted results were obtained,which coincided with the monitored *** developed GIS-based ANN water quality prediction system could serve as an efficient tool for engineers and decision makers.

关键词： water quality prediction Geographical Information System(GIS) artificial neural network integration system development

Perception and Recognition of Vocalization in Anuran Mate Choice

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Asian Herpetological Research 2020年第4期11卷 394-400页

作者： fang lu Yezhong TANG Qin CHEN Department of Ophthalmology West China HospitalSichuan UniversityChengdu 610041SichuanChina Chengdu Institute of Biology Chinese Academy of SciencesChengdu 610041SichuanChina

Vocal communications in frogs and toads have been highly diversified and become a hot topic in the fields of herpetology,ecology,and behavioral *** present short review summarized several interesting phenomena of vocal communication found mainly in anurans that might contribute to the individual identification of mates or rivals,including call matching,aggressive signaling,acoustic complexity,signal exaggeration,the first note effect and left hemisphere *** on the perception and recognition of vocal communications will facilitate our comprehension of the adaptive mechanisms and evolutionary paths of anuran signaling *** proposed here that comparative studies on acoustic signal structures,codes of sender status,and auditory neural responses based on phylogenetic relationships across species can highlight further the evolutionary trajectory in anurans.

关键词： anuran adaptive mechanism evolution phonotaxis vocal communication

A multichannel optical computing architecture for advanced machine vision

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Light(Science & Applications) 2022年第9期11卷 2235-2247页

作者： ZHIHAO XU XIAOYUN YUAN TIANKUANG ZHOU lu fang Sigma Laboratory Department of Electronic EngineeringTsinghua UniversityBeijingChina Beijing National Research Center for Information Science and Technology(BNRist) BeijingChina Tsinghua Shenzhen International Graduate School ShenzhenChina Institute for Brain and Cognitive Science Tsinqhua University(THUIBCS)BeijingChina

Endowed with the superior computing speed and energy efficiency,optical neural networks(ONNs)have attracted ever-growing attention in recent *** optical computing architectures are mainly single-channel due to the lack of advanced optical connection and interaction operators,solving simple tasks such as hand-written digit classification,saliency detection,*** limited computing capacity and scalability of single-channel ONNs restrict the optical implementation of advanced machine ***,we develop Monet:a multichannel optical neural network architecture for a universal multiple-input multiple-channel optical computing based on a novel projection-interference-prediction framework where the inter-and intra-channel connections are mapped to optical interference and *** our Monet,optical interference patterns are generated by projecting and interfering the multichannel inputs in a shared *** patterns encoding the correspondences together with feature embeddings are iteratively produced through the projection-interference process to predict the final output *** the first time,Monet validates that multichannel processing properties can be optically implemented with high-efficiency,enabling real-world intelligent multichannel-processing tasks solved via optical computing,including 3D/motion *** experiments on different scenarios demonstrate the effectiveness of Monet in handling advanced machine vision tasks with comparative accuracy as the electronic counterparts yet achieving a ten-fold improvement in computing *** intelligent computing,the trends of dealing with real-world advanced tasks are *** the capacity and scalability limitations of single-channel ONN and further exploring the multichannel processing potential of wave optics,we anticipate that the proposed technique will accelerate the development of more powerful optical Al as critical support for modern advanced mach

关键词： computing multichannel projection

Local Walsh-average-based estimation and variable selection for single-index models

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Science China Mathematics 2019年第10期62卷 1977-1996页

作者： Jing Yang fang lu Hu Yang Key Laboratory of High Performance Computing and StochasticInformation Processing(Ministry of Education of China) College of Mathematics and Computer ScienceHunan Normal UniversityChangsha410081China College of Mathematics and Statistics Chongqing UniversityChongqing401331China

We propose a robust estimation procedure based on local Walsh-average regression(LWR) for single-index models. Our novel method provides a root-n consistent estimate of the single-index parameter under some mild regularity conditions;the estimate of the unknown link function converges at the usual rate for the nonparametric estimation of a univariate covariate. We theoretically demonstrate that the new estimators show significant efficiency gain across a wide spectrum of non-normal error distributions and have almost no loss of efficiency for the normal error. Even in the worst case, the asymptotic relative efficiency(ARE) has a lower bound compared with the least squares(LS) estimates;the lower bounds of the AREs are 0.864 and 0.8896 for the single-index parameter and nonparametric function, respectively. Moreover, the ARE of the proposed LWR-based approach versus the ARE of the LS-based method has an expression that is closely related to the ARE of the signed-rank Wilcoxon test as compared with the t-test. In addition, to obtain a sparse estimate of the single-index parameter, we develop a variable selection procedure by combining the estimation method with smoothly clipped absolute deviation penalty;this procedure is shown to possess the oracle property. We also propose a Bayes information criterion(BIC)-type criterion for selecting the tuning parameter and further prove its ability to consistently identify the true model. We conduct some Monte Carlo simulations and a real data analysis to illustrate the finite sample performance of the proposed methods.

关键词： single-index models local Walsh-average regression asymptotic relative efficiency variable selection oracle property

Generalized braided Hopf algebras

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Applied Mathematics(A Journal of Chinese Universities) 2009年第1期24卷 105-113页

作者： lu Zhong-jian fang Xiao-li Department of Mathematics Shaoxing College of Arts and Sciences Shaoxing 312000 China

The concept of （f, σ）-pair （B, H）is introduced, where B and H are Hopf algebras. A braided tensor category which is a tensor subcategory of the category ^HM of left H-comodules through an （f, σ）-pair is constructed. In particularly, a Yang-Baxter equation is got. A Hopf algebra is constructed as well in the Yetter-Drinfel＇d category H^HYD by twisting the multiplication of B.

关键词： (f, σ )-pair Yetter-Drinfel’d modules category braided Hopf algebra

Boundedness of Some Marcinkiewicz Integral Operators Related to Higher Order Commutators on Hardy Spaces

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Acta Mathematica Sinica,English Series 2006年第1期22卷 105-114页

作者： Shan Zhen lu Li fang XU Department of Mathematics Beijing Normal University Beijing 100875 P. R. China

In this paper, the authors study the boundedness properties of μΩ↑m,b generated by the function b ∈Lipβ（R^n）（0 〈β≤ 1/m） and the Marcinkiewicz integrals operator μΩ. The boundednesses are established on t... 详细信息

关键词： Marcinkiewicz integral Higher order commutator Lipshcitz space Hardy type space Herz space

Some Results on Distance Two Labelling of Outerplanar Graphs

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Acta Mathematicae Applicatae Sinica 2009年第1期25卷 21-32页

作者： Wei- fan Wang Xiao-fang lu Department of Mathematics Zhejiang Normal University Jinhua 321004 China Yiwu Industrial and Commercial College Zhejiang Yiwu 322000 China

Let G be an outerplanar graph with maximum degree △. Let χ（G^2） and A（G） denote the chromatic number of the square and the L（2, 1）-labelling number of G, respectively. In this paper we prove the following results：（1） χ（G^2） = 7 if △= 6; （2） λ（G） ≤ △ ＋5 if △ ≥ 4, and ）,（G）≤ 7 if △ = 3; and （3） there is an outerplanar graph G with △ = 4 such that ）λ（G） = 7. These improve some known results on the distance two labelling of outerplanar graphs.

关键词： L(2, 1)-labelling chromatic number outerplanar graph

Planning an adaptive reuse development of underutilized urban underground infrastructures:A case study of Qingdao,China

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Underground Space 2024年第1期14卷 18-33页

作者： Yong-Kang Qiao fang-Le Peng Yun-Hao Dong Chun-fang lu Research Center for Underground Space&Department of Geotechnical Engineering Tongji UniversityShanghai 200092China

Urban underground infrastructures(UUIs)are a vital component of built capital for urban ***,many cities are now home to a multitude of disused or underutilized UUIs,not least aged purpose-built underground facilities,causing a waste of valuable underground space resource *** the process of urban renewal,adaptive reuse can be an attractive solution to breathe new life into underutilized UUIs,while addressing some of the modern problems of the built environment by an economically feasible ***,there is a prevalent absence in the current literature of the overarching planning and decision-making approaches for an adaptive reuse development of underutilized *** the intention of addressing this shortfall,this paper first lays out development strategies,then sets the generic patterns for adaptive reuse of disused or underutilized *** the city of Qingdao,China as a case study,detailed planning and decision-making approaches with the aid of multi-source data and spatial analysis tools are *** is anticipated that the findings of this research will assist the adaptive reuse development of UUIs in providing theoretical guidance and empirical evidence,thereby enhancing the role of urban underground space use in contributing to urban revitalization and urban sustainability.

关键词： Urban underground infrastructures Underutilized Adaptive reuse Planning Urban renewal