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Characteristics of Vibration and Sound Radiation of Metro resilient Wheel

Chinese Journal of Mechanical Engineering 2019年第4期32卷 195-206页

作者： Xin Zhou Jian Han Yue Zhao Bing Wu Gong Cheng Shenghui Xu Xuesong Jin State Key Laboratory of Traction Power Southwest Jiaotong University Chengdu 610031 China School of Urban Rail Transportation Shanghai University of Engineering Science Shanghai 201620China College of Aviation Transportation ManageMent Civil Aviation Flight University of China Chengdu 618307China School of Rail Transportation Soochow University Suzhou 215131 China

resilient wheels are extensively used in urban rail transit, especially for tramway systems, owing to its advantages in noise reduction. A new type of resilient wheel for a metro is designed, and its characteristics of vibration and sound radiation, including the rolling noise of a resilient single wheel coupled with a track, are studied in this paper. A two-step research is presented. Firstly, laboratory experiments were conducted to obtain the vibration response of the designed resilient wheel under the radial excitation on its tread. Secondly, the rolling noise model of the resilient wheel coupled with a slab track used in a metro line is developed. The wheel model is based on the 3 D finite elementand boundary element methods and verified by using the experimental results obtained from the laboratory. The track vibration model is based on the wavenumber finite element method, and the track sound radiation is calculatedby using an e cient frequency-domain Rayleigh method. The interaction of the resilient wheel and the slab track is analyzed considering the measured wheel/rail roughness of the metro. The contribution of the resilient wheel to the reduction of wheel/rail system noise is analyzed. The results show that the resilient wheel can e ectively reduce the wheel/rail rolling noise by approximately 2 dB(A) to 3 dB(A), mainly because the radiated noise by the rail is reduced. In addition, the elastic modulus of the rubber has an important influence on the noise reduction of resilient wheels.

关键词： resilient wheel Wheel/rail rolling noise Noise reduction Laboratory experiment Finite element and boundary element methods

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Predicting resilient modulus of recycled concrete and clay masonry blends for pavement applications using soft computing techniques

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Frontiers of Structural and Civil Engineering 2019年第6期13卷 1379-1392页

作者： Mosbeh R.KALOOP Alaa R.GABR Sherif M.EL-BADAWY Ali ARISHA Sayed SHWALLY Jong Wan HU Department of Civil and Environmental Engineering Incheon National UniversityIncheon 22012South Korea Incheon Disaster Prevention Research Center Incheon National UniversityIncheon 22012South Korea Department of Public Works and Civil Engineering Mansoura UniversityMansoura 35516Egypt

To date,very few researchers employed the Least Square Support Vector Machine(LSSVM)in predicting the resilient modulus(Mr)of Unbound Granular Materials(UGMs).This paper focused on the development of a LSSVM model to predict the MT of recycled materials for pavement applications and comparison with other different models such as Regression,and Artificial Neural Network(ANN).Blends of Recycled Concrete Aggregate(RCA)with Recycled Clay Masonry(RCM)with proportions of 100/0,90/10,80/20,70/30,55/45,40/60,20/80,and 0/100 by the total aggregate mass were evaluated for use as ***/RCM materials were collected from dumps on the sides of roads around Mansoura city,*** investigated blends were evaluated experimentally by routine and advanced tests and the Mr values were detennined by Repeated Load Triaxial Test(RLTT).Regression,ANN,and LSSVM models were utilized and compared in predicting the Mr of the investigated blends optimizing the best design *** showed that the Mx values of the investigated RCA/RCM blends were generally increased with the decrease in RCM *** analyses were utilized for evaluating the performance of the developed models and the inputs sensitivity ***,the results approved that the LSSVM model can be used as a novel tool to estimate the Mx of the investigated RCA/RCM blends.

关键词： Least Square Support Vector Machine Artificial Neural Network resilient modulus Recycled Concrete Aggregate Recycled Clay Masonry

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Cloud-based parallel power flow calculation using resilient distributed datasets and directed acyclic graph

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Journal of Modern Power Systems and Clean Energy 2019年第1期7卷 65-77页

作者： Dewen WANG Fangfang ZHOU Jiangman LI School of Control and Computer Engineering North China Electric Power University

With the integration of distributed generation and the construction of cross-regional long-distance power grids, power systems become larger and more *** require faster computing speed and better scalability for power flow calculations to support unit *** on the analysis of a variety of parallelization methods, this paper deploys the large-scale power flow calculation task on a cloud computing platform using resilient distributed datasets(RDDs).It optimizes a directed acyclic graph that is stored in the RDDs to solve the low performance problem of the MapReduce *** paper constructs and simulates a power flow calculation on a large-scale power system based on standard IEEE test *** are conducted on Spark cluster which is deployed as a cloud computing *** show that the advantages of this method are not obvious at small scale, but the performance is superior to the stand-alone model and the MapReduce model for large-scale *** addition, running time will be reduced when adding cluster *** not tested under practical conditions, this paper provides a new way of thinking about parallel power flow calculations in large-scale power systems.

关键词： Power flow calculation Parallel programming model Distributed memory-shared model resilient distributed datasets(RDDs) Directed acyclic graph(DAG)

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A Construction of 1-resilient Boolean Functions with Good Cryptographic Properties

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Journal of Systems Science & Complexity 2018年第4期31卷 1042-1064页

作者： SHAN Jinyong HU Lei ZENG Xiangyong LI Chunlei SKLOIS Institute of Information Engineering Chinese Academy of Sciences Beijing 100093 China DCS Chinese Academy of Sciences Beijing 100093 China School of Cyber Security University of Chinese Academy of Sciences Beijing 100049 China Faculty of Mathematics and Statistics Hubei Key Laboratory of Applied Mathematics Hubei University Wuhan 430062 China SKLOIS Institute of Information Engineering Chinese Academy of Sciences Beijing 100093China Department of Informatics University of Bergen N-5020 Bergen Norway

This paper proposes a general method to construct 1-resilient Boolean functions by modifying the Tu-Deng and Tang-Carlet-Tang functions. Cryptographic properties such as algebraic degree, nonlinearity and algebraic immunity are also considered. A sufficient condition of the modified func- tions with optimal algebraic degree in terms of the Siegenthaler bound is proposed. The authors obtain a lower bound on the nonlinearity of the Tang-Carlet-Tang functions, which is slightly better than the known result. If the authors do not break the ＂continuity＂ of the support and zero sets, the functions constructed in this paper have suboptimal algebraic immunity. Finally, four specific classes of 1-resilient Boolean functions constructed from this construction and with the mentioned good cryptographic properties are proposed. Experimental results show that there are many 1-resilient Boolean functions have higher nonlinearities than known l-resilient functions modified by Tu-Deng and Tang- Carlet-Tang functions.

关键词： Algebraic immunity Boolean functions correlation immunity nonlinearity resilient

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High-Speed Trains Automatic Operation with Protection Constraints: A resilient Nonlinear Gain-based Feedback Control Approach

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IEEE/CAA Journal of Automatica Sinica 2019年第4期6卷 992-999页

作者： Shigen Gao Yuhan Hou Hairong Dong Sebastian Stichel Bin Ning IEEE the State Key Laboratory of Rail Traffic Control and Safety Beijing Jiaotong UniversityBeijing 100044China the Division of Rail Vehicles KTH Royal Inititute of Technology

This paper addresses the control design for automatic train operation of high-speed trains with protection constraints.A new resilient nonlinear gain-based feedback control approach is proposed,which is capable of guaranteeing,under some proper non-restrictive initial conditions,the protection constraints control raised by the distance-to-go(moving authority)curve and automatic train protection in practice.A new hyperbolic tangent function-based model is presented to mimic the whole operation process of high-speed *** proposed feedback control methods are easily implementable and computationally inexpensive because the presence of only two feedback gains guarantee satisfactory tracking performance and closed-loop stability,no adaptations of unknown parameters,function approximation of unknown nonlinearities,and attenuation of external disturbances in the proposed control ***,rigorous proofs and comparative simulation results are given to demonstrate the effectiveness of the proposed approaches.

关键词： Automatic train operation high-speed train nonlinear gain feedback protection constraint resilient control

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Households’ Willingness to Pay for Disaster resilient Safe Drinking Water Sources in Southwestern Coastal Bangladesh

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International Journal of Disaster Risk Science 2019年第4期10卷 544-556页

作者： Md.Sariful Islam Sonia Afrin Md.Nasif Ahsan Mohammed Ziaul Haider Tasnim Murad Mamun Debasish Kumar Das Economics Discipline Khulna UniversityKhulna 9208Bangladesh

Nonfunctionality of engineered water sources after two catastrophic cyclones—Sidr in November 2007 and Aila in May 2009—created acute scarcity of safe drinking water in coastal *** objective of this study was to estimate households’willingness to pay(WTP)for disaster resilient water sources in Dacope upazila of Khulna District in southwestern coastal *** applying the double bounded dichotomous contingent valuation method to a dataset of 250 randomly selected households,we found that the mean WTP is BDT 263 and that inaccessibility to functional safe drinking water sources is the most significant determining factor of households’*** mean WTP for a disaster resilient water source project in the study area,we measured a present value of aggregate WTP over project’s life span worth about BDT 624(USD 7.37)million,which is about14.30 times the present value of project’s aggregate establishment and maintenance ***,charging the local inhabitants a water tariff at mean WTP would lead to the exclusion of around 50%of the people from getting access to the improved water services or create a free riding *** simulation exercises this study determined that the socially optimal water tariff is BDT 50 per *** tariff would not only generate revenue of more than five times the project cost but would also create access to disaster resilient improved drinking water sources for almost 99%of the people.

关键词： Bangladesh Disaster resilient safe drinking water Double bounded contingent valuation Household willingness to pay

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DSC modelling for predicting resilient modulus of crushed rock base as a road base material for Western Australia roads

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交通运输工程学报 2013年第2期13卷 10-16页

作者： KHOBKLANG Pakdee VIMONSATIT Vanissorn JITSANGIAM Peerapong NIKRAZ Hamid Department of Civil Engineering Curtin UniversityGPO Box U1987 Perth 6845Western AustraliaAustralia

In order to increase the applied efficiency of crushed rock base(CRB) in pavement structure design for Western Australia roads,the material modelling based on the experimental results was investigated,and the disturbed state concept(DSC) was used to predict the resilient modulus of CRB because of its simplicity and strong ability in capturing the elastic and inelastic responses of materials to *** actual deformation of DSC,at any loading state,was determined from its assumed relative intact(RI) *** DSC equation of CRB was constructed by using a set of experimental results of resilient modulus tests,and an idealized material model,namely the linear elastic model,of relative intact(RI) part was *** results reveal that the resilient modulus-applied stress relationships back-predicted by using the DSC modelling are consistent with the experimental results,so,the DSC equation is suited for predicting the resilient modulus of CRB ***,the model and the equation coming from the test results are conducted in accordance with the Austroads standard,so further investigation and validation with respect to the field behaviours of pavement structure should be performed.

关键词： pavement engineering CRB resilient modulus DSC RI triaxial test

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resilient Modulus of Compacted Lateritic Soils from Senegal at OPM Conditions

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Geomaterials 2013年第4期3卷 165-171页

作者： Fatou Samb Meissa Fall Yves Berthaud Makhaly Ba Laboratoire d’ Alembert—Université Pierre et Marie Curie Paris France Laboratoire de Mécanique et Modélisation—UFR Sciences de l’ Ingénieur Université de Thiès Thiès Sénégal

Repeated load triaxial tests were performed on five compacted gravel lateritic soils collected from different locations in Senegal: Sébikotane, Dougar, Pa Lo, Mont-Rolland and Ngoundiane. The study revealed that resilient modulus decreases with the increase of the bulk and deviatoric stress in constant confining pressure. In addition, resilient modulus increases with the percentage of cement for appreciably equal contents of moisture. This effect tends to stop for higher stress. Besides, correlations were made with some models of resilient modulus such as the Uzan-Witczack model (Witczack and Uzan, 1988 [1]) and the National Highway Research Program (NCHRP) model (2004 [2]). The study confirms that both models give very good results with the best correlations being obtained with the Uzan-Witczack model.

关键词： Gravel Lateritic Soils resilient Modulus Mechanical Behaviour Pavement Cyclic Triaxial Test Mechanistic Design

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resilient PNT Concept Frame

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Journal of Geodesy and Geoinformation Science 2019年第3期2卷 1-7页

作者： Yuanxi YANG State Key Laboratory of Geo-information Engineering Xi’an Research Institute of Surveying and Mapping Xi’an 710054 China

The concept of resilient positioning, navigation and timing (PNT) is described. The definition of resilient PNT is given, the relationship between integrated (or comprehensive) PNT and resilient PNT is analyzed, and it is pointed out that the integrated PNT is the foundation of resilient PNT. resilient PNT should be divided into resilient sensor integration, resilient functional model and resilient stochastic model. The strategy and principles of resilient integration of sensors are discussed. The resilient integration of sensors should be designed following the optimal, available, compatible and interoperable principles. The concepts of resilient functional model and possible modification strategies of the different functional models are also described. Several possible optimal routes for resilient stochastic model improvements are also set forth. It is pointed out that the optimal improvements of stochastic models for multi PNT sources should follow the same variance scale. At last, the resilient PNT data fusion for state parameters are given based on the resilient functional and stochastic models.

关键词： resilient positioning, navigation and timing (PNT) integrated PNT micro PNT resilient functional model resilient stochastic model

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resilient Modulus of Unbound Aggregate Base Courses from Senegal (West Africa)

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Open Journal of Civil Engineering 2011年第1期1卷 1-6页

作者： Makhaly Ba Meissa Fall Fatou Samb Déthié Sarr Mapathé Ndiaye 不详

This paper presents the results of research conducted to investigate the resilient Modulus (Mr) of unbound aggregates used as pavement layer in Senegal (West Africa) as well as the effect of water content and density on the resilient Modulus of the materials tested. Four different aggregates was collected from different sites within Senegal and then subjected to repeated load triaxial tests. Test results showed that the Bandia limestone is around 44% stiffer than the basalt, and 71% to 104% stiffer that the Black and the Red quartzites (GNB and GRB). The basalt is 21% to 43% stiffer than the GNB and the GRB. Basalt specimens compacted at Wopt– 2% were 30% stiffer than basalt specimens compacted at Wopt and 40% stiffer than those com- pacted at Wopt+ 2%. The Summary resilient Modulus (SRM) at Wopt– 2% is 22% higher than SRM at Wopt and 35% higher than SRM at Wopt+ 2% for the GRB and the GNB. The SRM at Wopt– 2% is 30% higher than SRM at Wopt and 40% higher than SRM at Wopt+ 2%, for the Basalt. For the Bandia limestone, the SRM at Wopt– 2% is 81% higher than SRM at Wopt and 126% higher than SRM at Wopt+ 2%. Results show also that the resilient Modulus increases around 25% when relative density increases from 77% to 119% and the variation is more significant at high stress states than at low stress state. Results of statistical analysis and coefficients of determination (R2) showed that the Uzan and NCHRP models are more suitable to predict the resilient Modulus of the aggregates tested.

关键词： resilient Modulus Summary resilient Modulus Quartzite Basalt Bandia Limestone Un-bound Aggregates

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