Archive

20 October 2021, Volume 40 Issue 10 Previous Issue   
---
Transportation Infrastructure Engineering
Transportation Equipment
Transportation+Big Data & Artificial Intelligence



For Selected:

Download Citations EndNote Ris BibTeX

Toggle Thumbnails

Transportation Infrastructure Engineering

Select

Some Thoughts on the High-Quality Development of Water Transport in Chengdu-Chongqing Area Twin City Economic Circle HUANG Zhendong 2021, 40(10): 1-6.  DOI: 10.3969/j.issn.1674-0696.2021.10.01 Abstract ( )   PDF (422KB) ( )   Aiming at several issues concerning the high-quality development of water transport in Chengdu-Chongqing area twin city economic circle, the historical opportunities for the high-quality development of Chongqing water transport and research foucuses were analyzed. The ecological environment problems of the construction of a new shipping channel in the Three Gorges of the Yangtze River were discussed. The research shows that Chongqing is the shipping center in the upper reaches of the Yangtze River and an important starting point for the high-quality development of water transportation; a moderately advanced viewpoint of comprehensive transportation system construction is put forward. The “Chongqing-New Europe” China EU train transportation and the construction of new land and sea channels should be vigorously developed,which will integrate into the domestic and international cycle. References | Related Articles | Metrics

Select

Ecological Sustainable Development Assessment of Golden Waterway in the Upper Yangtze River LI Wenjie1, TANG Boming1, YANG Shengfa1, WANG Hao2, DU Hongbo1, WAN Yu1 2021, 40(10): 7-13.  DOI: 10.3969/j.issn.1674-0696.2021.10.02 Abstract ( )   PDF (569KB) ( )   The capacity of the golden waterway in the upper Yangtze River is insufficient to meet the growth of shipping demand due to the low grade of waterways in the upper reaches of the Yangtze River and the congestion of Three Gorges ship lock. It is advisable to make decisions as soon as possible on the carrying capacity improvement construction project of the golden channel in the upper reaches of the Yangtze River and evaluate the ecological sustainability of the channel, so as to support the construction of the golden channel in the upper reaches of the Yangtze River under the priority of ecological protection. Based on the evaluation system with comprehensive consideration of waterway development, economic efficiency and ecological pressure, aiming at the golden channel in the upper reaches of the Yangtze River, the calculation method of relevant indicators was improved. The ecological sustainability of the secondary channel project from Yibin to Chongqing and the new channel project of Three Gorges water transportation was evaluated. Results indicate that after the implementation of the secondary channel construction project of Yibin-Chongqing section, the channel development rate has increased from 41% to 55%, which is still lower than the overall average development rate (67%) of the Yangtze River trunk channel; the economic benefit index increases significantly, and the ecological pressure index increases from 0.33 to 0.47, which doesn’t exceed the critical threshold of ecological sustainability. After the implementation of the new channel project of Three Gorges, the development rate only increases from 68% to 69%, the economic benefit index increases significantly, and the ecological pressure index increases slightly from 0.48 to 0.49. The construction of the secondary channel from Chongqing to Yibin and the construction of the new waterway of the Three Gorges meet the requirements of ecological sustainable development. The research results can provide theoretical support for the decision-making and construction of the golden channel related projects in the upper reaches of the Yangtze River. References | Related Articles | Metrics

Select

Path of Building a Strong Bridge Country Based on the Hong Kong-Zhuhai-Macao Bridge MENG Fanchao, LIU Minghu 2021, 40(10): 14-19.  DOI: 10.3969/j.issn.1674-0696.2021.10.03 Abstract ( )   PDF (4599KB) ( )   The construction background, objectives, bridge structure and landscape culture design scheme of the Hong Kong-Zhuhai-Macao Bridge were introduced, and the achievements and experience in the construction of the Hong Kong-Zhuhai-Macao Bridge were summarized. The innovative achievements of new materials, new structures, new technologies, new processes and new equipment in bridge engineering under the construction concept of “large-scale, factory, standardization and assembly” were summarized. The high-quality development concept, industrialization technology path, construction key points, system and mechanism innovation of Chinas bridge power construction were put forward under the background of building a transportation power. References | Related Articles | Metrics

Select

Research and Application of Bridge Internal Steel Structure Disease Detection ZHOU Jianting1,2，XIA Runchuan1,2，ZHANG Hong 1,2 2021, 40(10): 20-28.  DOI: 10.3969/j.issn.1674-0696.2021.10.04 Abstract ( )   PDF (6654KB) ( )   The internal steel structure diseases of bridges are highly hidden and difficult to detect, which will easily cause unpredictable structural damages. Therefore, how to realize the timely detection and accurate diagnosis of these diseases has become a major research problem to be solved. Based on the principle of self-magnetic flux leakage, the correlation between the magnetic field variation and the steel structure damage was revealed. Then the research on the non-destructive detection of bridge internal steel structure diseases was carried out by using this common feature. Focusing on three kinds of bridge internal diseases such as reinforcement corrosion, cable corrosion and broken wire and reinforcement stress failure, the research results obtained by the authors team in in detection methods, equipment development and application were summarized. Moreover, the technical characteristics of common detection methods were compared and analyzed, laying a research foundation for promoting the rapid development of bridge non-destructive testing technology. References | Related Articles | Metrics

Select

Discussion on the Development of Bridge Prefabricated Technology and Industrial Manufacturing ZHOU Zhixiang1,3, ZHONG Shixiang2, ZHANG Jiangtao1, ZOU Yang1, LIANG Huaping2, GUO Jincen1,3, JIANG Jinlong1 2021, 40(10): 29-40.  DOI: 10.3969/j.issn.1674-0696.2021.10.05 Abstract ( )   PDF (10433KB) ( )   Aiming at the construction of standard span bridges with large quantity and wide range, the development of the construction technology of common concrete bridges was briefly introduced. Based on decades of knowledge of bridge structure theory and application research, the advantages and problems of prefabricated bridge construction technology which had been used for decades and short-term prefabricated concrete bridge construction technology which was in the development period were discussed. The development trend of prefabricated bridge with comprehensive advantages was explored. Meanwhile, the common structural system of standard span steel-concrete composite bridge and the development of prefabricated construction technology were briefly introduced, and the prefabricated structure and construction technology of steel-concrete composite beam bridge without cast-in-situ slab joint concrete were explored. According to the unique geographical conditions and strategic positioning of Hainan province, the concept of fully assembled steel-concrete composite beam bridge with NHNR shear connection was proposed, and the industrialized manufacturing scheme of manufacturing bridge components in the factory, the conventional transportation to the bridge site and the mechanized assembly to form a steel-concrete composite beam bridge was discussed. References | Related Articles | Metrics

Select

Development and Prospect of Bridge Underground Diaphragm Wall Foundation LIU Minghu 2021, 40(10): 41-51.  DOI: 10.3969/j.issn.1674-0696.2021.10.06 Abstract ( )   PDF (2080KB) ( )   The construction goal of transportation power and the innovation-driven development strategy put forward the requirements for new structure and new technology of bridge engineering, and the new underground diaphragm wall foundation highly conforms to the requirements. The types of bridge underground diaphragm wall structure and its application, exploration and development in engineering were summarized. The key factors that restricted the development and application of the complete underground diaphragm wall foundation were analyzed. The key technical problems existing in the design and construction and the development solutions were expounded, and the development trend and application prospect of diaphragm wall foundation in bridge engineering construction were prospected. The analysis results show that all kinds of diaphragm wall foundations have been practiced and explored in different degrees in China.The slit-wall diaphragm wall foundation, shaft diaphragm wall foundation and the composite diaphragm wall foundation combined with both have unique advantages in the aspects of structure, construction, economy, safety and environmental protection, and have broad application prospects, but their development is restricted by many factors.In the short term, for general geological conditions, the partial diaphragm wall foundation of the gravity anchorage of suspension bridge will still be widely used in engineering practice as a comprehensive scheme with better selection.The application of shaft type diaphragm wall foundation or shaft type and strip wall composite diaphragm wall foundation in bridge tower and suspension bridge gravity anchorage in non-water area and shallow water area which can be cofferdam or island construction has strong practical demand and practical significance.It is of universal value to widely apply strip diaphragm wall foundation in conventional bridges, especially those with seismic requirements.It is the development path and focus of work to carry out extensive and in-depth research on the theory, test, design method and key construction technology of shaft type and compound diaphragm wall foundation, compile design guidelines and technical specifications and actively promote and apply them. References | Related Articles | Metrics

Select

Nonlinear Buckling Analysis of Concrete Encasement Process of Arch Bridge with CFST Stiff Skeleton GUO Zengwei, CHENG Hao, ZHOU Shuixing 2021, 40(10): 52-62.  DOI: 10.3969/j.issn.1674-0696.2021.10.07 Abstract ( )   PDF (4658KB) ( )   The accurate grasp of structural stability of concrete encasement stage of arch bridge with stiff skeleton has become the key to ensure its construction safety. In order to study the stability of long-span CFTS arch bridge with stiff skeleton in the concrete encasement process, a 600 m main span arch bridge with stiff skeleton was taken as an example, and the nonlinear buckling behavior of the stiff skeleton arch during the concrete encasement process was analyzed. Besides, the influence of geometric nonlinearity and material nonlinearity on the stability of main arch was also explored. The components that may suffer from local instability problem were discovered, and the causes of component instability were determined on the basis of the stability mechanism; moreover, the stability strengthening measures were put forward. The research results show that with the pouring of outer concrete, the double nonlinear performance of main arch becomes more and more obvious. Before the overall instability of the structure, some members may have been locally unstable. Both material nonlinearity and geometric nonlinearity must be taken into account in stability analysis of stiff skeleton arch bridge. Otherwise, the ultimate bearing capacity will be overestimated. However, it may not be easy to find the weak structure of potential local instability of the structure only by double nonlinear analysis. In order to more clearly recognize the instability mechanism of main arch structure during the loading process, it is necessary to analyze the evolution process of the structural stress behavior under the condition of material nonlinearity. In the concrete encasement process of main arch, the cross brace web near the arch foot may be locally unstable. Strengthening the lateral support of the transverse bracing web members can effectively enhance the stability of the transverse web members. References | Related Articles | Metrics

Select

Near-Fault Seismic Response of Large-Span CFST Tied Arch Bridge Considering Soil-Pile Interaction XU Lueqin1,2, ZHANG Ling1, GONG Hao1 2021, 40(10): 63-72.  DOI: 10.3969/j.issn.1674-0696.2021.10.08 Abstract ( )   PDF (3884KB) ( )   To investigate the effects of soil-pile interaction on the near-fault seismic response of long-span concrete-filled-steel-tubular (CFST) tied arch bridge, aiming at six kinds of widely-used pile-soil interaction simulation methods in bridge seismic analysis, the corresponding analytical models were studied and established. Nine groups of near-fault ground motion records were selected as excitation to carry out the numerical simulation analysis of the whole bridge. Based on the direct embedding method, the influence of pile-soil interaction on the seismic response of key components of arch bridge was compared and studied. The results show that the soil-pile interaction has a significant impact on the seismic response of tied arch bridge, which can increase the seismic response of key components of the bridge by more than 50%. The most adverse effect is found on the seismic internal force of arch ribs and wind braces, and the smallest impact is found on the seismic displacement of arch ribs. The influence rules of soil-pile interaction simulated by different methods on the seismic response of tied arch bridge are consistent, but the influence degree is different, which shows that these simulation methods can be used to judge the favorable or unfavorable effects of pile-soil interaction. Finally, within the scope of this study, the nonlinear effect of soil-pile interaction is limited, and using m method with less calculation to replace p-y curve method can also get ideal analysis results. References | Related Articles | Metrics

Select

Dynamic Response and Crashworthiness Optimization of Prefabricated Piers Connected by UHPC under Vehicle Impact WANG Yinhui1,2, FENG Zeniu1, LUO Zheng2 2021, 40(10): 73-81.  DOI: 10.3969/j.issn.1674-0696.2021.10.09 Abstract ( )   PDF (4658KB) ( )   Based on LS-DYNA software, the nonlinear finite element analysis of vehicle impact piers was carried out based on UHPC connected prefabricated viaduct piers. Firstly, the CSCM constitutive model was obtained through the UHPC block axial compression test and drop hammer test. Secondly, the similarities and differences of impact force, deformation development law and internal force response between precast assembled piers and cast-in-place piers under different impact velocities were analyzed. Finally, the crashworthiness of precast assembled piers was furtherly optimized by changing the key parameters such as the diameter of joint reinforcement, the friction coefficient at the joint and the UHPC height at the lower joint. The results show that the vibration period of the precast piers after impact is obviously shorter than that of cast-in-place piers. The crack of assembled column develops from the upper end of the cup mouth at the pier bottom to the back side, while the integral column develops from the bottom of the pier. The bottom of two piers is prone to shear failure, and the place of impact is prone to bending failure. Among them, bending failure may occur on the pier top of assembled column, and shear failure may occur on the pier top of the whole cast column. There is little difference between the crashworthiness of assembled column and integral column. In addition, when the height of UHPC is increased, the crashworthiness of the assembled column is improved most obviously, compared with the diameter of the joint steel bar and the friction coefficient at the joint. The damage and dynamic response of the pier are also obviously reduced, which can effectively improve the crashworthiness of the pier. References | Related Articles | Metrics

Select

Evolution Law of Pier Top Displacement of Existing Pier Considering the Construction Process of Adjacent Road WANG Duoyin, XING Lei, DUAN Lunliang 2021, 40(10): 82-90.  DOI: 10.3969/j.issn.1674-0696.2021.10.10 Abstract ( )   PDF (2930KB) ( )   In view of the problem that the adjacent road construction would affect the displacement characteristics of the pier top of the existing pier by changing the contact stress distribution of the pile-soil interface of the pile foundation of the existing pier, an in-service pier of Chongqing Rail Transit Line 3 was taken as the engineering background, and a three-dimensional numerical model describing the foundation-base-pier interaction in the process of critical road construction was established by using the large-scale general finite element software ABAQUS. Based on the proposed model, the influence of road excavation, paving and operation on the horizontal and vertical displacement of pier top were studied. The research results show that: after subgrade excavation, with the increase of excavation depth (H), the horizontal displacement of pier top will continue to increase and the vertical settlement of pier top will continue to decrease. With the increase of the distance (L) from the road to the pier edge, the horizontal displacement of pier top will continue to decrease; however, the vertical settlement of pier top will continue to increase. Compared with subgrade excavation, the horizontal displacement of pier top caused by road paving tends to decrease, but the vertical displacement tends to increase. In the later operation of newly-built road, the horizontal displacement of bridge pier top caused by traffic load is relatively small, while the vertical settlement is significantly larger than that caused by road construction. In the obtained curve of horizontal displacement of pier top changing with excavation depth, the turning point of pier top horizontal displacement from close to the road to far away from the road varies during road construction. In the subgrade excavation, when the excavation depth is about 1.8 m, the horizontal displacement direction of pier top changes. In road paving, when the excavation depth is about 2.6 m, the horizontal displacement direction of pier top changes. In the later operation, when the excavation depth is about 3.1 m, the horizontal displacement direction of pier top changes. References | Related Articles | Metrics

Select

Experimental Study on Optimization Algorithm for Acoustic Emission Location of Concrete Damage Location Based on Wave Velocity HE Zhaoyi1, YANG Kang2, LI Dongxue2, ZHOU Hanlin2 2021, 40(10): 91-96.  DOI: 10.3969/j.issn.1674-0696.2021.10.11 Abstract ( )   PDF (7290KB) ( )   In order to study the attenuation law of acoustic wave in concrete and improve the positioning accuracy of acoustic emission, the wave velocity attenuation test of concrete beam was carried out, and the variation of wave velocity changing with distance was calculated, and the attenuation formula of wave velocity with distance was given. An exhaustive algorithm for acoustic emission source location based on wave velocity attenuation was established. The damage and fracture test of cement concrete trabecula under three-point loading mode was carried out, and the acoustic emission acquisition instrument was used to collect the acoustic emission parameters. An exhaustive localization algorithm based on wave velocity attenuation was used to locate the damage points during loading, and compared with the original damage point location algorithm with constant wave velocity. The research results show that the wave velocity of standard acoustic emission signal in concrete is seriously attenuated with the increase of distance. The initial reference velocity is 4745m/s, which has decreased to 2124m/s when the propagation is 600mm. In the brittle failure stage, the number of locating points of acoustic emission optimization algorithm increases from 4 to 16, and the proportion increases from 17.4% to 70%, and its accuracy is significantly higher than that of time difference location method, which is of great significance to the location and detection of concrete damage. References | Related Articles | Metrics

Select

Research Progress of Bituminous Mixture Meso-structure Based on Image Technology ZHU Hongzhou1,2, TAN Qiqi1, FAN Shiping1, WAN Guoqi1 2021, 40(10): 97-110.  DOI: 10.3969/j.issn.1674-0696.2021.10.12 Abstract ( )   PDF (2320KB) ( )   Based on digital image processing technology, the meso-structure of asphalt mixtures was studied. Firstly, the research progress of static and dynamic recognition of asphalt mixture meso-structure was reviewed. Then, a flowchart of digital image processing technology was listed and the method of obtaining the internal structure image of asphalt mixture (X-ray CT technology) was introduced in detail. The research progress in describing the internal structure characteristics of mixture through image processing technology, that is, aggregate shape and distribution, contact characteristics and void distribution rule, was discussed. Finally, the three kinds of numerical simulation methods with finite element, discrete element and boundary element and the virtual test on the meso-structure characteristics of asphalt mixture were introduced. The research shows that X-ray CT non-destructive scanning technology can better identify the internal meso-structure characteristics of asphalt mixtures; the numerical simulation combined with finite element, discrete element or boundary element methods can establish an organic relationship between the internal meso-structure and macro performance of asphalt mixture; the application of virtual test can help to understand the macro test results. However, in the study of aggregate shape and distribution, a unified evaluation index has not yet been formed and different researchers use different evaluation indexes. The accuracy and application scope of X-ray CT technology need to be further improved. There is no effective method to distinguish aggregate, asphalt mortar and void. By summarizing the application of digital image processing technology to the meso-structure of asphalt mixture, it is expected to provide reference for the follow-up macro-meso-micro research of asphalt mixture. References | Related Articles | Metrics

Select

Sorption Characteristics of Fe3O4 Modified Biochar on Arsenic FAN Jianxin, QIN Liang, DUAN Ting, ZOU Lan, QI Zenglin 2021, 40(10): 111-118.  DOI: 10.3969/j.issn.1674-0696.2021.10.13 Abstract ( )   PDF (7496KB) ( )   In order to study the removal effect and adsorption mechanism of arsenic in water by Fe3O4 modified biochar, wheat straw was selected as raw material to prepare raw biochar (BC), and two modified biochar (MBC-1 and MBC-2) with different iron-to-carbon ratios （MFe3O4∶MBiochar=1∶4, 1∶2） was designed by co-precipitation method. SEM, BET, FT-IR, and XRD spectrogram were applied to determine the surface morphology, specific surface area, porous structures, and functional groups of BC, MBC-1 and MBC-2; and XPS and EDS were used to analyze physical and chemical properties of MBC-1. The influence of biochar dosage and solution pH value on the adsorption was investigated. The adsorption kinetics and isothermal adsorption experiments were carried out to study the adsorption characteristics of As on BC, MBC-1 and MBC-2, and the adsorption mechanism of As on Fe3O4 modified biochar was discussed. The results show that Fe3O4 is successfully loaded onto biochar, and the specific surface areas of MBC-1 and MBC-2 are 1.69 and 2.26 times as much as that of BC, respectively. The removal rate of As by BC, MBC-1 and MBC-2 increases with the increase of biochar dosage and decreases with the increase of solution pH value. The adsorption of As by BC, MBC-1 and MBC-2 accords with the pseudo-second-order kinetic model, and the adsorption isotherm curve accords with the Freundlich adsorption model. The maximum adsorption capacity of MBC-1 and MBC-2 for arsenic fitted by Langmuir model are 141 and 184 times higher than that of BC, respectively. The more Fe3O4 loaded, the better the adsorption effect. The adsorption of As by MBC-1 and MBC-2 includes electrostatic attraction, coordination reaction and ion exchange. Fe3O4 loaded in biochar participates in the redox reaction of As, changes the occurrence form of As and affects the adsorption and fixation of As. References | Related Articles | Metrics

Transportation Equipment

Select

Scientifical Promotion of the Development and Application of Automatic Driving Technology — Embrace New Technologies and Meet New Challenges PANG Song 2021, 40(10): 119-122.  DOI: 10.3969/j.issn.1674-0696.2021.10.14 Abstract ( )   PDF (403KB) ( )   Automatic driving realizes partial or complete automatic operation of road traffic through the organic integration of transportation tools, infrastructure and operation control, which is a profound change for the traditional transportation mode and travel mode. Firstly, the concept and significance of automatic driving was summarized. Then, three key technologies of autonomous driving vehicle, including environmental perception, autonomous decision-making and motion control, were described. And then, the problems of the development of automatic driving technology existing in four aspects were analyzed, such as laws and regulations and ethical problems to be solved, lack of testing and evaluation methods, improvement of standard system and attention to system safety. Finally, it is pointed out that in the future, automatic driving may develop in parallel along two routes: promote and apply the auxiliary driving function below L3 on open roads to improve driving safety and road traffic efficiency; promote the normal operation of unmanned technologies such as automatic driving in the park with less restrictions by laws and regulations and relatively closed environment, and build supporting intelligent infrastructure to improve production and operation efficiency. References | Related Articles | Metrics

Select

Fault Diagnosis Method of Motor-Gear Drive Coupling System of Urban Rail Train Based on Electromagnetic Torque XU Xiangyang, FAN Linfang 2021, 40(10): 123-129.  DOI: 10.3969/j.issn.1674-0696.2021.10.15 Abstract ( )   PDF (2948KB) ( )   Aiming at the problem that the electrical and mechanical parts of the motor gear transmission system of urban rail train were difficult to be coupled, resulting in their independent research, the nonlinear magnetic conductivity of the motor and the time-varying meshing stiffness of the gear were comprehensively considered, and the electromechanical coupling dynamic model of the traction transmission system of urban rail train based on permeance dynamic model (PNM) was established. Based on the proposed model, considering the short-circuit fault of stator turn winding and the fracture fault of squirrel cage rotor guide bar, the dynamic response of electromechanical coupling system under fault was obtained. The fault diagnosis was carried out on the basis of electromagnetic torque, and the diagnosis results were compared with those of vector control single motor model. The research results show that in the low frequency domain, the electromagnetic torque spectrum of PNM is larger at the fault frequency than that of vector control single motor model, and it is easier to identify the fault; in the high frequency domain, PNM electromagnetic torque diagnosis method can identify more obvious high-order harmonic components of power frequency, and has more advantages in fault diagnosis of electromechanical coupling system. The fault diagnosis method based on electromagnetic torque can effectively diagnose the faults of electromechanical coupling system of urban rail train, and provide theoretical support for fault detection technology without sensor. References | Related Articles | Metrics

Transportation+Big Data & Artificial Intelligence

Select

Optimization Study of Multi-center Joint Distribution and Pickup Network Alliance WANG Yong, LUO Siyu 2021, 40(10): 130-145.  DOI: 10.3969/j.issn.1674-0696.2021.10.16 Abstract ( )   PDF (5500KB) ( )   To overcome the deficiencies of the collaborative alliance construction and profit allocation mechanism design in the multi-center joint distribution and pickup network, an alliance optimization strategy of the multi-center joint distribution and pickup network was proposed. Firstly, a bi-objective optimal model was developed to minimize the total operating cost and the number of vehicles in the network. Secondly, a hybrid heuristic algorithm integrating the k-means clustering algorithm and the improved non-dominated sorting genetic algorithm-Ⅱ (Im-NSGA-Ⅱ) was then proposed to solve the model. Both the idea of the greedy algorithm and the elite retention strategy were introduced in the proposed hybrid heuristic algorithm to improve the global convergence performance and the local optimization capability to search for optimal solutions. In addition, compared with NSGA-Ⅱ and MOGA algorithms, the effectiveness of the proposed algorithm was verified. Thirdly, the minimum costs remaining savings method (MCRS) was exploited to study the profit allocation of the collaborative alliance in the multi-center joint distribution and pickup network, and then the optimal joining sequence selection and the stability of collaborative alliances were discussed. Finally, the proposed model and algorithm were verified by a case study. Results show that the proposed approach can realize the optimal resource distribution in a multi-center joint distribution and pickup network and reduce the total operating cost, which can provide reference and method reference for the optimization of multi-echelon joint distribution and pickup network, and provide decision support for sustainable urban logistics network planning and the construction of shared logistics cooperation alliance. References | Related Articles | Metrics

Select

Customer Satisfaction Evaluation Model of Logistics Distribution Service Based on the CCSI FU Zhiyan1,2, LIU Keliang1, HUANG Yong1, CHEN Jian1 2021, 40(10): 146-153.  DOI: 10.3969/j.issn.1674-0696.2021.10.17 Abstract ( )   PDF (1241KB) ( )   In order to solve the lack of quantitative description method for customer satisfaction in logistics distribution services, based on the Chinese customer satisfaction index model (CCSI), the impact of various factors on customer satisfaction and loyalty from the perspective of customer psychological perception was explored through the four influencing factors such as perceived service quality, expected service quality, brand image and perceived service cost. And a customer satisfaction evaluation model for logistics distribution service was constructed. The second-order structural equation model was used to simplify the variable concept, and then the impact of various influencing factors on customer satisfaction of logistics distribution services as well as the relationship between various influencing factors and satisfaction and loyalty was analyzed quantitatively. Finally, the proposed model was applied to the case analysis of Chongqing. The results show that the perceived service quality and perceived service cost have the most significant impact on the customer satisfaction of logistics distribution services, the impact of brand image cannot be ignored, and customer satisfaction significantly determines customer loyalty. References | Related Articles | Metrics

Select

Multi-Objective Optimization for Multi-Modal Transportation Routing in Uncertain Environment PENG Yong, XIAO Yunpeng, LUO Yijuan 2021, 40(10): 154-160.  DOI: 10.3969/j.issn.1674-0696.2021.10.18 Abstract ( )   PDF (1361KB) ( )   Aiming at the multi-modal transport network in uncertain environment, a bi-objective optimization model with minimum total transport cost and duration was constructed by considering the influencing factors such as transshipment cost, duration and transport mode timetable. Monte Carlo (MC) simulation approach was used to deal with the uncertainty of transport network and the multi-objective ant colony algorithm combined with non-dominated sorting was designed to solve the Pareto frontier solution. In order to solve the problem of low solution quality of basic ant colony algorithm caused by slow convergence speed and premature convergence, a direction heuristic factor was added into the state transition strategy, and a “max-min ant system” was introduced in the pheromone update strategy, so as to improve the quality of the solution. Finally, an example was given to verify the optimization efficiency of the improved ant colony algorithm, and five decision paths that fully met their requirements for different goals were provided for the decision-maker. References | Related Articles | Metrics

Select

Tourism Route Planning of Urban Suburb Based on Tourist Experience LU Baichuan1,2, YANG Jieyi1, WANG Xin1 2021, 40(10): 161-170.  DOI: 10.3969/j.issn.1674-0696.2021.10.19 Abstract ( )   PDF (5416KB) ( )   According to the characteristics of flexibility and individuality of self-driving tour in suburban areas, and comprehensively considering the influence of road traffic and tourist attractions on the travel experience of tourists, a method for planning tourism routes in suburban cities based on tourist experience was proposed. First of all, based on the comprehensive analysis of the influence of road traffic factors and tourist attractions attributes on the experience of self-driving tourists, an optimal path selection model between attractions based on the comprehensive road resistance was established, and Floyd algorithm was used to solve the model. Then, on the basis of the travel cost and the utility of scenic spots, the sequence planning model of scenic spots based on tourist experience was built, and the optimal tourist route was solved by genetic algorithm. Finally, an example was used to verify. It shows that compared with the traditional route planning method based on the shortest distance, the tourism route planning method of suburban areas based on the tourist experience is more in line with the actual travel situation of self-driving tourists, which effectively reduces the travel time of tourists and the waiting time of attractions. References | Related Articles | Metrics

Select

Commuting Characteristics of Public Transport Based on IC Card and GPS Data LI Shuqing, LIU Yaohong, QIU Haoji 2021, 40(10): 171-177.  DOI: 10.3969/j.issn.1674-0696.2021.10.20 Abstract ( )   PDF (782KB) ( )   The public transport commuter is an important part of public transport passenger flow. The characteristics of public transport commuting travel are the data basis for formulating public transport priority development strategy, public transport planning and optimization as well as operation management. Aiming at the traditional analysis method of fragmented bus commuter travel characteristics with “car” as the research object, the calculation method of four dimensional index parameters such as bus travel chain characteristics, section passenger flow imbalance coefficient, job-residence balance level and line viscosity coefficient was systematically analyzed and put forward, which was based on bus IC card and GPS data and from the perspective of bus passengers “people”. Taking the bus passengers of 47 representative lines in the main urban area of Chongqing for 5 consecutive working days as an example, the characteristics of commuting trips were analyzed. The results show that the commuting passenger flow in the main urban area of Chongqing has less transfer times, larger demand for long-distance bus passenger flow and higher level of job-residence balance; and about a quarter of commuters have strong stickiness to route selection. References | Related Articles | Metrics

Select

Low-Illumination Road Traffic Sign Recognition Based on Improved VGG Model ZHAO Shuen, LIU Wei 2021, 40(10): 178-184.  DOI: 10.3969/j.issn.1674-0696.2021.10.21 Abstract ( )   PDF (15514KB) ( )   Aiming at the problems of low brightness, high saturation, blurred image, and inaccurate recognition of road traffic sign images under low illumination conditions, a fast road traffic sign recognition method based on the dilated convolution-VGG (DC-VGG) model was proposed. Firstly, the contrast limited adaptive histogram equalization (CLAHE) algorithm was used to equalize the V channel in the image H (hue) S (saturation) V (color lightness) space, so as to achieve low illumination image brightness enhancement. Secondly, a threshold was set in the HSV space to segment the specified colors, and the traffic signs were located through contour detection. Then, based on the deep convolutional generative adversarial networks (DCGAN), the data samples of the real traffic sign images were enhanced, to improve the robustness of the classification model. Finally, the proposed DC-VGG lightweight model was used to realize the rapid recognition of traffic signs. It is verified that the recognition accuracy of the proposed method is 94.12%, and it can detect in real time under poor hardware conditions. References | Related Articles | Metrics