制动工况下车轮不圆对车辆动力学性能的影响
兰清群1,宋福2
1.安徽交通职业技术学院,安徽合肥230051;2.深圳地铁运营集团有限公司,广东深圳518000
摘要:为了研究制动工况下车轮不圆对车辆的垂向和纵向加速度特性的影响,在固定坐标系中建立多体动力学模型,输入制动转矩,计算制动状态下车辆的动力学响应。仿真计算时,主要考虑当前比较普遍的周期性车轮不圆8阶多边形缺陷以及常用和紧急情况下的制动工况。研究结果表明:车轮不圆的影响在车轮和转向架构架的加速度响应中占主导地位,且纵向加速度远大于垂向加速度;在制动工况下,无缺陷车轮和有不圆缺陷车轮的车体加速度在悬挂装置的阻尼下振幅逐渐衰减;车辆运行速度为35 km/h时,车轮对的固有纵向振动频率与车轮不圆产生的振动频率接近,产生了共振效应。
关键词:车轮不圆;常用制动;紧急制动;垂向加速度;纵向加速度
Effect of outofround wheel on vehicle dynamics performance underbraking condition
LAN Qingqun1,SONG Fu2
1.Anhui Transportation Vocational and Technical College, Hefei 230051, China;2. Shenzhen Metro Operation Group Co., Ltd., Shenzhen 518000, China
Abstract:In order to study the effect of the outof round wheel on the vertical and longitudinal acceleration characteristics of the vehicle under braking conditions, a multibody dynamics model is established in the fixed coordinate system. In the input of the brake torque, the dynamic response of the vehicle under braking is calculated. In the simulation calculation, the periodic wheel polygon defects are mainly considered, and the braking torque under normal and emergent conditions is also taken into consideration. The research results are shown as follows. The influence of the outof round wheel dominates in the acceleration response of the wheels and steering structures, and the vertical acceleration is much greater than the longitudinal acceleration. With or without braking, the body acceleration of the defectfree wheel and the outofround wheel gradually reduces at the damping amplitude of the suspension. In addition, at a vehicle operating speed of 35 km/h, the natural longitudinal vibration frequency of the wheelis close to the vibration frequency produced by the outof round wheel, resulting in a resonance effect.
Keywords:outofround wheel;service braking;emergency braking;vertical acceleration,longitudinal acceleration
重型商用车排放试验对比分析
刘刚1,2,王继磊1,2,李建东1,2,栾振1,2,王福龙1,2
1.内燃机可靠性国家重点实验室,山东潍坊261061;2.潍柴动力股份有限公司发动机研究院,山东潍坊261061
摘要:分析重型商用车转毂排放试验的影响因素,并与道路排放试验进行对比分析。试验研究表明:转毂排放试验法和道路排放试验法的试验方法和结果计算方法存在很大差异,转毂排放试验法受运行工况、行驶阻力、预热等因素影响较大,绝大多数车型转毂排放试验法NOx的排放高于道路排放试验法,尤其是客车车型排放最大相差约85%,因此,建议开发自卸车、客车等新车型时,道路排放试验应结合转毂排放试验的结果进一步分析验证。提出集成道路实际工况和转毂工况的复合路谱概念。
关键词:转毂排放试验法;道路排放试验法;NOx排放;影响因素
Comparative analysis of emission tests forheavyduty commercial vehicle
LIU Gang1,2, WANG Jilei1,2,LI Jiandong1,2, LUAN Zhen1,2, WANG Fulong1,2
1.State Key Laboratory of Engine Reliability, Weifang 261061 , China;2.R & D Center, Weichai Power Co., Ltd., Weifang 261061, China
Abstract:In this paper, the influencing factors of the rotary hub emission test of the heavy commercial vehicle are analyzed and compared with the onroad emission test. The experimental research shows that there are great differences among the test methods of the rotary hub emission, the onroad emission and the method of the results calculation. The rotary hub method is greatly affected by operating conditions, driving resistance, preheating and other factors. For most vehicle models, the amount of the NOx from the rotary hub emission test method is higher than that from the onroad emission test method, and especially for the passenger vehicles, with about 85% of a maximum difference. Therefore, it is suggested that when developing new models such as dump trucks and buses, the onroad emission tests should be further analyzed and verified in combination with the test results of the rotary hub emission. The concept of the composite road spectrum is proposed integrating the actual working conditions of the road with the working conditions of the rotary hub.
Keywords:rotary hub emission test method; onroad emission test method;NOx emission; influencing factor
基于改进人工蜂群BP神经网络的PM2.5浓度预测模型
胡俊,杨辉军,程晨
安徽国际商务职业学院信息工程学院,安徽合肥231131
摘要:为解决传统细颗粒物质(particulate matter,PM)浓度预测模型研究角度片面、非线性程度较高、预测精度不高的问题,建立基于改进人工蜂群反向传播(back propagation,BP)神经网络的PM2.5质量浓度预测模型,将搜索形式与跟随蜂选择概率设为改进角度,优化人工蜂群算法的寻优精度与收敛速率,在BP神经网络模型中引入改进人工蜂群算法,更新网络权重,避免使其陷入局部最小化;依据PM2.5浓度多种影响因素之间的关联性,采用灰色关联分析策略,识别所有因素间的发展趋势依赖程度,选取具有较大关联系数的污染气体,设定其质量浓度、温度及相对湿度为预测模型的变量因子,利用三倍标准差方法舍弃异常数据,根据三位二进制编码,标签化样本数据,通过创建的预测模型,获取PM2.5质量浓度预测结果。仿真分析表明:基于改进人工蜂群BP神经网络的PM2.5质量浓度预测模型的稳定性得到大幅提升,预测精准性具有明显优势。
关键词:人工蜂群;BP神经网络;PM2.5浓度;变量因子
PM2.5 concentration prediction model based onBP neural network of improved artificial bee colony
HU Jun, YANG Huijun, CHENG Chen
School of Information Engineering, Anhui Vocational College of International Business, Hefei 231131, China
Abstract:The research angle of the traditional particulate matter (PM2.5) concentration prediction model is too onesided, resulting in a high degree of nonlinearity, which affects the accuracy of prediction. A PM2.5 concentration prediction model is established based on the back propagation (BP) neural network of the improved artificial bee colony. The search form and the bee selection probability are set as an improved angle, the optimization accuracy and convergence rate of the artificial bee colony algorithm are optimized, an improved artificial bee colony algorithm is introduced in the BP neural network model, and the network weight is updated to avoid the local minimization. According to the correlation in various influencing factors of PM2.5 concentration, a gray correlation analysis strategy is used to identify the degree of dependence of the development trend among all factors. The polluted gas with a larger correlation coefficient is selected to set its concentration, temperature and relative humidity as the variable factors of the prediction model, the triple standard deviation method is used to discard the abnormal data, and then the result of the PM2.5 concentration prediction is obtained through the established prediction model according to the threebit binary coding and the labeling sample data. The simulation experiments show that the stability of the PM2.5 concentration prediction model based on the BP neural network of the improved artificial bee colony has also been greatly improved, and the prediction accuracy has obvious advantages.
Keywords:artificial bee colony; BP neural network; PM2.5 concentration; variable factor
基于高速自然驾驶数据的驾驶员跟车特性
孙宏图1,刘兴亮2,黄昆2
1.天津工业大学机械工程学院,天津300387;2.中国汽车技术研究中心有限公司,天津300300
摘要:为研究驾驶员在高速行车时的跟车特性,基于实车试验采集驾驶员高速公路上的自然驾驶跟车数据,通过Matlab/Simulink联合CANape软件对数据进行跟车判定与筛选,并对驾驶员在加减速以及稳速跟车阶段的跟车特性进行分析。研究结果表明:驾驶员在高速公路跟车过程中跟车间距随车速升高而增加;在稳速及加减速跟车时,跟车间距呈现螺旋状变化;自车加速度与跟车时距存在一定关联,而与自车车速、跟车间距没有明显相关性。研究结果可为自适应巡航系统及驾驶员跟车仿真研究提供参考依据。
关键词:高速公路;自然驾驶数据;跟车特性;跟车间距;跟车时距
Research on driver′s followup characteristics based onnatural highspeed driving data
SUN Hongtu1, LIU Xingliang2, HUANG Kun2
1. School of Mechanical Engineering, Tianjin Polytechnic University, Tianjin 300387, China;2. China Automotive Technology Research Center Co.,Ltd., Tianjin 300300, China
Abstract: In order to study the driver′s followup characteristics during the highspeed driving, the Matlab/Simulink and CANape software are used to judge and screen the natural driving data based on the realcar test to collect the followup data of the driver′s natural driving on the expressway. Then the followup characteristics are analyzed in the followup phase of the driver accelerating or decelerating and keeping the speed. The test results show that the followup distance increases with the increase of the driving speed during the followup process on the expressway; the followup distance shows a spiral change at the steady speed and acceleration or deceleration; there is a certain correlation between the acceleration of driver′s own car and followup distance, and there is no obvious correlation with the speed of driver′s own car and followup distance. The results can provide important reference for the adaptive followup system and the research of driver′s followup simulation.
Keywords:expressway;natural driving data;followup characteristics;followup distance;followup time
基于SEM-Logit整合模型的旅游铁路交通出行分担率预测
仇智勇1,岳鑫2,周建尧2*,段冉冉2
1.中国中铁二院工程集团有限责任公司交通与城市规划设计研究院,四川成都610031;2.西南交通大学交通运输与物流学院,四川成都611756
摘要:依托都江堰至四姑娘山山地轨道交通扶贫项目工程规划阶段的客流调查分析与预测,分析新建旅游铁路背景下的交通出行方式分担率预测方法。基于旅游铁路出行问卷调查数据,引入舒适性、观光性和便捷性等潜变量,构建结构方程模型(structural equation modeling,SEM)与离散选择(Logit)模型相结合的旅游铁路出行方式选择SEM-Logit模型,利用本地、外地两类游客的个人属性和旅游出行数据,结合2022年交通经济适应情况,预测得到2022年旅游铁路、旅游巴士和小汽车的分担率分别为43.52%、19.15%和37.33%。研究表明:提出的预测方法能够为提高旅游铁路客流预测的可靠性、推动旅游铁路规划的科学性提供支撑。
关键词:旅游铁路;交通方式;SEM-Logit;分担率
Share rate prediction of tourist railway transportation based on SEM-Logit integrated model
QIU Zhiyong1, YUE Xin2, ZHOU Jianyao2*, DUAN Ranran2
1. Institute of Transportation and Urban Planning & Design, China Railway Eryuan Engineering Group Co.,Ltd., Chengdu 610031, China;2. School of Transportation and Logistics, Southwest Jiaotong University, Chengdu 611756, China
Abstract:Based on the investigation, analysis and forecast of passenger flow in the planning stage of the poverty alleviation project of Dujiangyan to Four Girls Mountain Rail Transit, this paper analyzes the prediction method of share rate of transportation modes under the background of the newlybuilt tourist railway. Based on the survey data of the travel questionnaire of the tourist railway, the potential variables such as ease, sightseeing and convenience are introduced, and the SEM-Logit model, the selection of the travel mode of the tourist railway combining the structural equation model (SEM) with the discrete choice (Logit) model, is established. Using the individual characteristics and travel data of local and outside tourists, combined with the economic and applicable situation of transportation in 2022, it is predicted that the share rate of tourist railways, tourist buses and cars in 2022 is 43.52%, 19.15% and 37.33% respectively. The research shows that the proposed prediction method can provide support for improving the reliability of passenger flow prediction and promoting the scientific planning of tourist railways.
Keywords:tourist railway; transportation mode; SEM-Logit; share rate
基于KMeans聚类与灰色关联分析的城市交通状况分析
陈永胜
深圳高速工程顾问有限公司交通规划事业部, 广东深圳518000
摘要:为了分析交通拥堵的影响因素,将数据挖掘技术用于城市拥堵成因分析中,提出一种基于聚类与灰色系统理论的城市交通状况分析方法。构建包括交通拥堵状况、交通基础设施、城市国民经济与社会发展的城市交通状况分析指标体系,利用KMeans聚类法对全国36个重点城市的交通状况进行等级划分,并将划分结果进行灰色关联分析,研究交通状况与交通基础设施建设、国民经济与社会发展水平之间的内在关联。研究表明:城市每千人民用汽车拥有量与建设区道路密度是影响交通拥堵状况的主导因素,每万人公共汽车拥有量、从业人口密度以及常住人口密度为主要间接影响因素。
关键词:交通拥堵;KMeans聚类;灰色关联分析;影响因素
Analytical study of urban traffic conditions based onKMeans clustering and grey correlation analysis
CHEN Yongsheng
Department of Transportation Planning, Shenzhen Expressway Engineering Consultants Co., Ltd., Shenzhen 518000, China
Abstract:To analyze the factors affecting traffic congestion, the data mining technology is used in the analysis of the causes of urban congestion and a method of urban traffic condition analysis based on clustering and grey system theory is proposed. From the aspects of urban traffic congestion, traffic infrastructure, and the city′s national economy and social development, this paper establishes an analysis index system of urban traffic conditions. Then, the Kmeans clustering method is used to divide the traffic conditions of 36 key cities in China into levels. As a result, the clustering results are used in the grey correlation analysis to study the traffic congestion, infrastructure constructionand the internal relationship between the national economy and social development level. The research shows that the car ownership per thousand people and the road density in the construction area are the main factors affecting the traffic congestion, while the ownership of public vehicles per ten thousand people, the density of employed population and the density of permanent residents are the main indirect factors.
Keywords:traffic congestion; KMeans clustering; grey relation analysis; influence factor
地铁线网末班列车时刻表协同编制优化
杨艳
广西交通技师学院,广西南宁530001
摘要:以地铁线网为对象,为实现各线路末班列车换乘衔接最优,编制时刻表的优化方案,考虑实际运行的限制因素和必要条件,采用规划建模方法处理列车时刻表编制问题的组合优化;针对问题的复杂性和计算效率需求,采用粒子群算法求解新建模型。数值试验结果表明:该方法流程运算效率较高,原始时刻表的衔接指标在优化过程中改善幅度达66.7%。所建优化模型符合实际工程条件,算法准确有效,可为地铁线路运营领域提供理论依据和工程实践参考。
关键词:地铁线路;末班列车;时刻表;粒子群算法
Collaborative optimization for schedules of last trains in a subway network
YANG Yan
Guangxi Traffic Technician College, Nanning 530001, China
Abstract:The subway network taken as the object, the optimization scheme of timetables is compiled in order to realize the optimal connection of last trains on each line. Taking into account the constraints and necessary conditions of the actual operation, the method of programming models is used to deal with the combination optimization. In view of the complexity and the requirements of computational efficiency of the problem, the particle swarm optimization is used to solve the newly established model. The results of numerical experiments show that the process operation efficiency of this method is high, and the convergence index of the original timetable is improved by 66.7% in the optimization process. The optimized model applies to the actual engineering conditions, and the algorithm is accurate and effective, which can provide the basic theoretical basis and reference for the engineering practice in the operation field of subway lines.
Keywords:subway line; last train; time table; particle swarm optimization
山东-台湾拓展邮轮旅游的关键因素
戴友榆,冯小楠,石兴
山东交通学院国际商学院,山东威海264209
摘要:为分析海峡两岸邮轮旅游市场进展缓慢的问题,采用定性与定量相结合的方法,即宏观因素分析模型(politics economy society technology,PEST)嵌入态势分析法(strengths weaknesses opportunities threats,SWOT)与重要性-满意度分析法结合,探讨山东与台湾两省间拓展邮轮旅游的关键因素。从供给端而言,山东-台湾邮轮旅游市场的利基深厚,优势与机会明显;对消费者需求来说,重要的是积极拓展两省的邮轮旅游航线、丰富旅游体验。本研究可为推动山东与台湾两省邮轮旅游发展,完善邮轮产业服务链,培养邮轮专业人才,优化邮轮旅游产品,发挥邮轮行业协会作用,提供专业参考。
关键词:邮轮旅游;SWOT;PEST;重要性-满意度分析
Key factors of expanding cruise tourism between Shandong and Taiwan
DAI Youyu, FENG Xiaonan,SHI Xing
School of International Business, Shandong Jiaotong University, Weihai 264209, China
Abstract:In order to analyze the slow progress of the cruise tourism markets on both sides of the Taiwan Straits, a combination of qualitative and quantitative methods, namely, the combination of the embedded situation analysis(politics economy society technology, PEST) of the macro factor analysis model(strengths weaknesses opportunities threats, SWOT) and the importancesatisfaction analysis method, is used to discuss the key factors for expanding cruise tourism between Shandong and Taiwan provinces of China. From the supply side, ShandongTaiwan cruise tourism market has a deep niche with obvious advantages and opportunities. For the demand of customers, it is important to actively expand the cruise tourism routes of the two provinces to enrich travel experiences. This study can provide professional reference for promoting the development of cruise tourism in Shandong and Taiwan provinces, perfecting the service chain of the cruise industries, training cruise professionals, optimizing cruise tourism products and playing the role in cruise industry associations.
Keywords:cruise tourism;SWOT;PEST;importance satisfaction analysis
基于Seep 3D的透水性沥青路面结构组合设计
骆明金
昆山交通工程集团有限公司,江苏昆山215300
摘要:采用Seep 3D三维路面有限元建模,在非饱和渗流的理论基础上,以单层透水路面坡度与透水层厚度为变量,分析不同结构组合下透水性沥青路面产生路面径流时的临界降雨强度,模拟路表积水扩散与变化特征,提出适用于昆山市气候条件的单层透水性沥青路面结构的组合方案,为海绵城市水流通道和排水设施的布置提供参考。研究结果表明:路表产生积水时的临界降雨强度及积水位置与路面横坡和透水层厚度密切相关,昆山市单层透水性沥青路面最优结构组合为2.5%的横坡+4 cm透水层厚度结构,可最大限度地排出路表水,保证在大雨强度下不出现路表积水。
关键词:有限元;透水路面;路面横坡;临界降雨强度
Structure combination design of permeable asphalt pavement based on Seep 3D
LUO Mingjin
Kunshan Transportation Engineering Group Co.,Ltd., Kunshan 215300, China
Abstract:Based on the theory of unsaturated seepage, with the help of Seep 3D finite element model, taking the gradient and thickness of the single permeable pavement as variables, the critical rainfall intensity is analyzed when the permeable asphalt pavement produces the pavement runoff under different structure combinations, simulates the diffusion and changing characteristics of the surface ponding and puts forward the structure combination of the single permeable asphalt pavement which is suitable to the conditions of Kunshan′s climate, which provides reference for the layout of the water channel and drainage for the sponge cities. The research results show that the critical rainfall intensity and the wateraccumulating location are closely related to the cross slope and the thickness of the permeable layer of the pavement; the optimal structure combination of the single permeable asphalt pavement in Kunshan city is 2.5% of the cross slope and 4 cm of the thickness of the permeable layer, which can discharge the surface water to the greatest extent and ensure that the surface water will not appear under the intensity of heavy rain.
Keywords:finite element; permeable pavement; transverse slope; critical rainfall intensity
融合重力信息的似大地水准面精化模型
沈鑫,胡伍生*
东南大学交通学院,江苏南京211189
摘要:以二次多项式模型为基础,提出融合重力信息的多项式模型和融合重力信息的误差反向传播(error back propagation,BP)神经网络模型2种似大地水准面精化模型。通过试验验证,3种模型的检验点拟合中误差分别为±11.7 cm、±4.3 cm和±4.0 cm,重力信息可提高似大地水准面模型的拟合效果,BP神经网络模型的拟合精度最高,与二次多项式模型相比提高了65%。
关键词:似大地水准面精化;高程异常;EGM2008重力场模型;二阶多项式拟合法;BP神经网络
Quasigeoid refinement model fused with gravity information
SHEN Xin, HU Wusheng*
School of Transportation,Southeast University,Nanjing 211189,China
Abstract:Based on the quadratic polynomial model, two kinds of Quasigeoid refinement models are proposed: a polynomial model fused with gravity information, and a BP neural network methodfused with gravity information. Through the test verification, the checkpoint fitting error of the three models is ±117 cm, ±43 cm and ±40 cm respectively, the gravity information can improve the fitting effect of the Quasigeoid model, and the fitting accuracy of the BP neural network model is the highest, which is 65% higher than that of the quadratic polynomial model.
Keywords:quasigeoid refinement;height anomaly;EGM2008 gravity field model;quadratic polynomial fitting method;BP neural network
砂土地层不同开挖方法隧道围岩的竖向变形
闫茂旺
山东高速建设管理集团有限公司,山东济南250000
摘要:为研究地铁隧道穿越砂土地层区围岩竖向变形的问题,依托青岛地铁3号线河西-河东区间工程,采用FLAC 3D数值计算软件,选取预留核心土、上下台阶开挖、预注浆等6种工况,分别计算围岩稳定性及变形情况。计算结果表明:开挖前不注浆与注浆加固时,上下台阶预留核心土工况的最大竖向位移较上下台阶工况分别降低1815%、3924%;开挖上下台阶与开挖上下台阶预留核心土时,注浆工况的最大竖向位移较不注浆工况分别降低3356%、5069%。根据计算结果进行现场预注浆试验,优化选择预注浆、留核心土及上下台阶开挖方案,注浆压力为10~15 MPa。试验研究表明:注浆加固后围岩的强度指标提高了30%~50%,现场实测拱顶最大沉降为4290 mm,较好地控制了地铁隧道穿越砂土地层区产生的变形。
关键词:砂土地层;地铁隧道;数值模拟;核心土;围岩稳定性;预注浆试验
Vertical deformation of surrounding rock of tunnel under different excavation methods in sandy soil layer
YAN Maowang
Shandong Hispeed Construction Management Group Co., Ltd., Jinan 250000, China
Abstract:In order to study the vertical deformation of crossing the surrounding rock in the sandy layer area of the subway tunnel, relying on the project of the HexiHedong section of Qingdao Metro Line 3, the numerical calculation software FLAC 3D is used to select 6 working conditions, such as reserved core soil, excavation of the upper and lower steps, pregrouting and so on to calculate the stability and deformation of the surrounding rock respectively. The calculation results show as follows. When there are no grouting and grouting with reinforcement before excavation, the maximum vertical displacement can be reduced respectively by 18.15% and 39.24% under the condition of reserved core soil of upper and lower steps compared with that of upper and lower steps; When excavating the upper and lower steps and the reserved core soil of the upper and lower steps, the maximum vertical displacement under the grouting condition is 33.56% and 50.69% respectively lower than that under no grouting condition. According to the calculation results, the onsite pregrouting test is carried out, and the selection of the pregrouting, reserved core soil and excavation scheme of the upper and lower steps is optimized, and the grouting pressure is 1.0~1.5 MPa. The experimental results show that the strength index of the surrounding rock after the grouting reinforcement is increased by 30% to 50%, and the maximum settlement of the vault measured on site is 42.90 mm, which can control the deformation caused by crossing the sandy layer area of the subway tunnel.
Keywords:sandy layer; metro tunnel; numerical simulation; core soil; surrounding rock stability; pregrouting test
纳米材料至原子材料调控金属氧还原催化剂的研究进展
吴艳玲,李勉拓,孙翠翠
山东交通学院交通土建工程学院, 山东济南250357
摘要:综述Pt基和非贵金属氧还原催化剂材料的最新研究成果,基于单原子催化剂金属尺寸最小,配位结构独特,是金属利用率最高、活性最强的一类催化剂,发展迅速,是替代Pt基材料的潜在选择。总结近年来金属纳米材料到单原子催化剂材料在氧还原反应方面取得的进展,对单原子催化剂在氧还原反应中存在的挑战和未来发展方向进行展望。
关键词:单原子催化剂;氧还原反应;铂基催化剂;非贵金属催化剂
Progress in study of regulating metal oxygen reduction catalyst fromnanomaterial to atomic material
WU Yanling, LI Miantuo, SUN Cuicui
School of Transportation and Civil Engineering, Shandong Jiaotong University, Jinan 250357, China
Abstract:The latest research results of Ptbased and nonnoble metal oxygen reduction catalyst materials are summarized. The metal based on the singleatom catalyst is smallest in size and unique in mating structure, so such a catalyst is the one with the highest metal utilization rate and the most powerful activity, which is a potential alternative to the Ptbased material. It is summarized that the progress made in oxygen reduction reaction from nanomaterials to singleatom catalyst materials in recent years, and looking to the challenges and future developments of singleatom catalysts in the oxygen reduction reaction.
Keywords:singleatom catalyst; oxygen reduction reaction; platinumbased catalyst; nonnoble metalcatalyst