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Asian Agricultural Research 2018年第10期10卷 27-29页

作者： Huimin MA Chengfeng YU Wuhan Technology and Business University Wuhan 430000China

In the era of " Internet + ",the " Internet + tourism" comes into being,bringing unlimited development space and more possibilities to the traditional travel agency industry. Under the dual influence of development and impact,travel agencies start to take the road of transformation. Taking Hubei Comfort International Travel Service Co.,ltd. as an example,this paper analyzed and evaluated the current situations of Internet based transformation and upgrade,and came up with some pertinent recommendations.

关键词：旅游业旅行社经济发展发展现状

A Novel Model for Describing Rail Weld Irregularities and Predicting Wheel-Rail Forces Using a Machine Learning Approach

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Computer Modeling in Engineering & Sciences 2025年第1期142卷 555-577页

作者： Linlin Sun Zihui Wang Shukun Cui Ziquan Yan Weiping Hu Qingchun Meng State Key Laboratory of High-Speed Railway Track System China Academy of Railway Sciences Corporation LimitedBeijing100081China Railway Engineering Research Institute China Academy of Railway Sciences Corporation LimitedBeijing100081China School of Aeronautic Science and Engineering Beihang UniversityBeijing100191China

Rail weld irregularities are one of the primary excitation sources for vehicle-track interaction dynamics in modern high-speed *** can cause significant wheel-rail dynamic interactions,leading to wheel-rail noise,component damage,and *** researchers have employed the vehicle-track interaction dynamic model to study the dynamic interactions between wheel and rail induced by rail weld geometry ***,the cosine wave model used to simulate rail weld irregularities mainly focuses on the maximum value and neglects the geometric *** this study,novel theoretical models were developed for three categories of rail weld irregularities,based on measurements of the high-speed railway from Beijing to *** vertical dynamic forces in the time and frequency domains were compared under different running *** forces generated by the rail weld irregularities that were measured and modeled,respectively,were compared to validate the accuracy of the proposed ***,based on the numerical study,the impact force due to rail weld irrregularity is modeled using an Artificial Neural Network(ANN),and the optimum combination of parameters for this model is *** results showed that the proposed model provided a more accurate wheel/rail dynamic evaluation caused by rail weld irregularities than that established in the *** ANN model used in this paper can effectively predict the impact force due to rail weld irrregularity while reducing the computation time.

关键词： Rail weld irregularity high-speed railway vehicle-track coupled dynamics wheel/rail dynamic vertical force artificial neural networks

SensFL:Privacy-Preserving Vertical Federated Learning with Sensitive Regularization

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Computer Modeling in Engineering & Sciences 2025年第1期142卷 385-404页

作者： Chongzhen Zhang Zhichen Liu Xiangrui Xu Fuqiang Hu Jiao Dai Baigen Cai Wei Wang School of Automation and Intelligence Beijing Jiaotong UniversityBeijing100044China Shuohuang Railway Development Co. Ltd.National Energy GroupCangzhou062350China Beijing Key Laboratory of Security and Privacy in Intelligent Transportation School of Computer Science and TechnologyBeijing Jiaotong UniversityBeijing100044China

In the realm of Intelligent Railway Transportation Systems,effective multi-party collaboration is crucial due to concerns over privacy and data *** Federated Learning(VFL)has emerged as a promising approach to facilitate such collaboration,allowing diverse entities to collectively enhance machine learning models without the need to share sensitive training ***,existing works have highlighted VFL’s susceptibility to privacy inference attacks,where an honest but curious server could potentially reconstruct a client’s raw data from embeddings uploaded by the *** vulnerability poses a significant threat to VFL-based intelligent railway transportation *** this paper,we introduce SensFL,a novel privacy-enhancing method to against privacy inference attacks in ***,SensFL integrates regularization of the sensitivity of embeddings to the original data into the model training process,effectively limiting the information contained in shared *** reducing the sensitivity of embeddings to the original data,SensFL can effectively resist reverse privacy attacks and prevent the reconstruction of the original data from the *** experiments were conducted on four distinct datasets and three different models to demonstrate the efficacy of *** results show that SensFL can effectively mitigate privacy inference attacks while maintaining the accuracy of the primary learning *** results underscore SensFL’s potential to advance privacy protection technologies within VFL-based intelligent railway systems,addressing critical security concerns in collaborative learning environments.

关键词： Vertical federated learning privacy defenses

New Insights into the Shikimate and Aromatic Amino Acids Biosynthesis Pathways in Plants

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Molecular Plant 2010年第6期3卷 956-972页

作者： Vered Tzin Gad Galili Department of Plant Sciences The Weizmann Institute of Science Rehovot 76100 Israel

The aromatic amino acids phenylalanine, tyrosine, and tryptophan in plants are not only essential components of protein synthesis, but also serve as precursors for a wide range of secondary metabolites that are important for plant growth as well as for human nutrition and health. The aromatic amino acids are synthesized via the shikimate pathway followed by the branched aromatic amino acids biosynthesis pathway, with chorismate serving as a major intermediate branch point metabolite. Yet, the regulation and coordination of synthesis of these amino acids are still far from being understood. Recent studies on these pathways identified a number of alternative cross-regulated biosynthesis routes with unique evolutionary origins. Although the major route of Phe and Tyr biosynthesis in plants occurs via the intermediate metabolite arogenate, recent studies suggest that plants can also synthesize phenylalanine via the intermediate metabolite phenylpyruvate （PPY）, similarly to many microorganisms. Recent studies also identified a number of transcription factors regulating the expression of genes encoding enzymes of the shikimate and aromatic amino acids pathways as well as of multiple secondary metabolites derived from them in Arabidopsis and in other plant species. .

关键词： Carbon metabolism metabolomics metabolic regulation primary metabolism secondary metabolism-- phenylpropanoids and phenolics volatiles

Silicon Purification by a New Type of Solar Furnace

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Chinese Physics Letters 2009年第7期26卷 359-361页

作者：陈应天林晨星阿祚庥林文汉王亦楠 Department of Astronomy and Applied Physics University of Science and Technology of China Hefei 230026 Institute of Theoretical Physics Chinese Academy of Sciences Beijing 100190 Institute of Electrical Engineering Chinese Academy of Sciences Beijing 100190

We propose a new method to reveal a direct transformation from solar energy to solar electricity. Instead of using electricity in the process, we use concentrated solar rays with a crucibleless process to upgrade meta... 详细信息

关键词： Electronics and devices Optics quantum optics and lasers Environmental and Earth science

Heuristic algorithm based on the principle of minimum total potential energy(HAPE):a new algorithm for nesting problems

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2011年第11期12卷 860-872页

作者： Xiao LIU Jia-wei YE School of Civil and Transportation Engineering South China University of Technology Guangzhou 510640 China

We present a new algorithm for nesting *** equally spaced points are set on a sheet,and a piece is moved to one of the points and rotated by an *** the point and the rotation angle constitute the packing attitude of the *** propose a new algorithm named HAPE(Heuristic Algorithm based on the principle of minimum total Potential Energy) to find the optimal packing attitude at which the piece has the lowest center of *** addition,a new technique for polygon overlap testing is proposed which avoids the time-consuming calculation of no-fit-polygon(NFP).The detailed implementation of HAPE is presented and two computational experiments are *** first experiment is based on a real industrial problem and the second on 11 published benchmark *** a hill-climbing(HC) search method,the proposed algorithm performs well in comparison with other published solutions.

关键词： Packing Cutting Nesting Irregular Heuristic algorithm Minimum total potential energy

Aero-Thermal Performances of Leakage Flows Injection from the Endwall Slot in Linear Cascade of High-Pressure Turbine

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Journal of Thermal Science 2015年第1期24卷 49-57页

作者： Wan Aizon W Ghopa Zambri Harun Ken-ichi Funazaki Takemitsu Miura Department of Mechanical and Materials Engineering Universiti Kebangsaan Malaysia Department of Mechanical Engineering Iwate University

The existence of a gap between combustor and turbine endwall in the real gas turbine induces to the leakages phenomenon. However, the leakages could be used as a coolant to protect the endwaU surfaces from the hot gas since it could not be completely prevented. Thus, present study investigated the potential of leakage flows as a function of film cooling. In present study, the flow field at the downstream of high-pressure turbine blade has been investigated by 5-holes pitot tube. This is to reveal the aerodynamic performances under the influenced of leakage flows while the temperature measurement was conducted by thermoehromic liquid crystal （TLC）. Expe- rimental has significantly captured theaerodynamics effect of leakage flows near the blade downstream. Further- more, TLC measurement illustrated that the film cooling effectiveness contours were strongly influenced by the secondary flows behavior on the endwall region. Aero-thermal results were validated by the numerical simulation adopted by commercial sottware, ANSYS CFX 13. Both experimental and numerical simulation indicated almost similar trendinaero and also thermal behavior as the amount of leakage flows increases.

关键词： endwall fllmcooling leakage flows secondary flows aerodynamic loss film cooling effectiveness

Fire and retention island remnants have similar deadwood carbon stock a decade after disturbances in boreal forests of Alberta

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Forest Ecosystems 2024年第5期11卷 677-684页

作者： Richard Osei Lance P.Moore Rosanise A.Odell Marcel Schneider Tanvir Ahmed Shovon Charles A.Nock Department of Renewable Resources University of AlbertaEdmontonCanada Institut des Sciences de La Foret Temperee Universite Du Quebec en Outaouais58 Rue PrincipaleRiponJ0V 1V0QCCanada

In an attempt to reconcile wood extraction and forest biodiversity in managed boreal forests,ecosystem-based forest management(EBM)has become the de facto management *** forestry represents one prominent way that EBM is implemented in many parts of the *** patches commonly left after harvesting serve as analogues of fire island remnants,which are patches of unburned forests in the burned forest *** the persistence of retention patches has been questioned,few studies have attempted to quantitatively compare forest attributes in both burned and harvested *** part of a larger program examining multiple aspects of ecosystem function in fire and harvest island remnants,we investigated the impact of disturbance type(fire/harvest)and forest edges on C stock in snags and coarse woody debris(CWD)found in island remnants in mixedwood boreal forests of Alberta,*** C stock(in snags and CWD)was similar between the two disturbance types and edge plots had similar total deadwood C stocks to *** edges of island remnants had about two-fold more snag C stock than their interiors in both disturbance types,but C stock in CWD was unaffected by edge effects and disturbance *** results suggest that deadwood C dynamics in island remnants in fire and harvest disturbed boreal forests were similar,thus lending support for the continued implementation of retention forestry in Alberta.

关键词： Retention forestry Deadwood Ecosystem-based management Wildfires Boreal forest

Experimental seismic behavior of squat shear walls with precast concrete hollow moulds

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Earthquake Engineering and Engineering Vibration 2019年第4期18卷 871-886页

作者： Han Wenlong Zhao Zuozhou Qian Jiaru Zhang Yingbao Ma Tao Key Laboratory of Civil Engineering Safety and Durability of China Education Ministry Tsinghua University Beijing 100084 China China Institute of Building Standard Design & Research Beijing 100048 China Beijing Everest Green Building Technology ltd. Beijing 102209 China Beijing Institute of Architectural Design Beijing 100045 China

This study proposes an innovative precast shear wall system, called an EVE precast hollow shear wall structure (EVE-PHSW). Precast panels in EVE-PHSW are simultaneously precast with vertical and horizontal holes. Noncontact lap splices of rebars are used in vertical joints connecting adjacent precast panels for automated prefabrication and easy in situ erection. The seismic behavior of EVE walls was examined through a series of tests on six wall specimens with aspect ratios of 1.0~1.3. Test results showed that EVE wall specimens with inside cast-in situ concrete achieved the desired “strong bending and weak shear” and failed in shear mode. Common main diagonal cracks and brittle shear failure in squat cast-in situ walls were prevented. Inside cast-in situ concrete could signifi cantly improve the shear strength and stiff ness of EVE walls. The details of boundary elements (cast-in situ or prefabricated) and vertical joints (contiguous or spaced) had little eff ect on the global behavior of EVE walls. Noncontact lap splices in vertical joints could enable EVE walls to exhibit stable load-carrying capacity through extensive deformations. Evaluation on design codes revealed that both JGJ 3-2010 and ACI 318-14 provide conservative estimation of shear strength of EVE walls, and EVE walls achieved shear strength reserves comparative to cast-in situ walls. The recommended eff ective stiff ness for cast-in situ walls in ASCE 41-17 appeared to be appropriate for EVE walls.

关键词： precast concrete hollow mould low-aspect-ratio noncontact lap splice prefabricated boundary element vertical and horizontal joints seismic behavior