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Dynamic plugging regulating strategy of pipeline robot based on reinforcement learning

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Petroleum Science 2024年第1期21卷 597-608页

作者： Xing-Yuan Miao Hong Zhao college of Mechanical and transportation Engineering China University of PetroleumBeijing102249China

Pipeline isolation plugging robot (PIPR) is an important tool in pipeline maintenance operation. During the plugging process, the violent vibration will occur by the flow field, which can cause serious damage to the pipeline and PIPR. In this paper, we propose a dynamic regulating strategy to reduce the plugging-induced vibration by regulating the spoiler angle and plugging velocity. Firstly, the dynamic plugging simulation and experiment are performed to study the flow field changes during dynamic plugging. And the pressure difference is proposed to evaluate the degree of flow field vibration. Secondly, the mathematical models of pressure difference with plugging states and spoiler angles are established based on the extreme learning machine (ELM) optimized by improved sparrow search algorithm (ISSA). Finally, a modified Q-learning algorithm based on simulated annealing is applied to determine the optimal strategy for the spoiler angle and plugging velocity in real time. The results show that the proposed method can reduce the plugging-induced vibration by 19.9% and 32.7% on average, compared with single-regulating methods. This study can effectively ensure the stability of the plugging process.

关键词： Pipeline isolation plugging robot Plugging-induced vibration Dynamic regulating strategy Extreme learning machine Improved sparrow search algorithm Modified Q-learning algorithm

Fatigue Resistance of RCA Modified Asphalt Based on Dielectric Properties

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Journal of Wuhan University of Technology(Materials Science) 2024年第1期39卷 91-101页

作者：陆佳宝王国忠 HU Jiangsan LIU Zhongning college of Energy and transportation Engineering Inner Mongolia Agricultural UniversityHohhot 010018China

In order to study the anti-fatigue performance of RCA modified asphalt (RMA),the performance of RMA and 90#matrix asphalt with different modifier content were measured by asphalt penetration,ductility,softening point,Brookfield viscosity,rheological index,infrared spectrum and dielectric constant test.This paper discusses the changes of asphalt basic indexes,fatigue properties and asphalt components based on dielectric properties under different modifier contents,and analyzes the grey correlation degree between components and asphalt pavement performance indexes.The results show that the optimum content of RCA modifier is 16.7%of the asphalt quality according to the penetration,ductility,softening point,Brockfield viscosity,viscosity temperature curve and fatigue life.In the phase angle-strain curve,there is disorder in the latter part of the curve.According to the strain (ε_(d)) corresponding to the disorder point,a new fatigue failure criterion is proposed and proved.Based on the new asphalt fatigue failure criterion,the fatigue prediction model of asphalt mixture is improved,and the fatigue life predicted by the improved fatigue model is compared with the fatigue life obtained by four-point bending fatigue test.The results show that the proposed new asphalt fatigue failure criterion is reasonable,and the fatigue life predicted by the improved asphalt mixture fatigue prediction model is accurate.The research method of classifying asphalt components based on dielectric properties is simple and effective,and the components have a high correlation with the road performance of base asphalt and modified asphalt.

关键词： dielectric properties anti-fatigue performance fatigue failure criterion RCA modified asphalt

Optimal electric bus scheduling with multiple vehicle types considering coordinated recharging strategy

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Coupled Numerical Simulation of Electromagnetic and Flow Fields in a Magnetohydrodynamic Induction Pump

Jilin Daxue Xuebao (Gongxueban)/Journal of Jilin University (Engineering and Technology Edition) 2024年第5期54卷 1293-1301页

作者： Zhang, Ming-Ye Yang, Min Li, Yu Huang, Shi-Yu Li, Qing-Yun college of transportation Southeast University Nanjing 211189 China

To solve the problem of supply-demand mismatch caused by the imbalance of time-space passenger flow，this paper proposes an electric bus scheduling method with multiple vehicle types based on the characteristics of passenger flow variety. In view of the operating characteristics difference of multiple vehicle types，considering the time-of-use electricity price and coordinated charging strategy，an electric bus scheduling model is established to jointly optimize the vehicle driving plan，charging scheme and fleet configuration. A genetic algorithm model is designed to solve the problem，and a network in Nanjing are taken as examples to verify the effect of the model. compared with the small and large type scheduling scheme，the total system cost of the scheduling scheme with multiple vehicle types is reduced by 8.26% and 11.25%，respectively. The results show that the proposed method can not only improve the public transport service level，but also effectively reduce the operation cost of the public transport system. © 2024 Editorial Board of Jilin University. All rights reserved.

关键词： Electric buses

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Fluid Dynamics & Materials Processing 2024年第4期20卷 889-899页

作者： He Wang Ying He college of transportation Ludong UniversityYantai264025China college of Intelligent Manufacturing City College of HuizhouHuizhou516025China

Magnetohydrodynamic(MHD)induction pumps are contactless pumps able to withstand harsh environments.The rate of fluid flow through the pump directly affects the efficiency and stability of the device.To explore the influence of induction pump settings on the related delivery speed,in this study,a numerical model for coupled electromagnetic and flow field effects is introduced and used to simulate liquid metal lithium flow in the induction pump.The effects of current intensity,frequency,coil turns and coil winding size on the velocity of the working fluid are analyzed.It is shown that the first three parameters have a significant impact,while changes in the coil turns have a negligible influence.The maximum increase in working fluid velocity within the pump for the parameter combination investigated in this paper is approximately 618%.As the frequency is increased from 20 to 60 Hz,the maximum increase in the mean flow rate of the working fluid is approximately 241%.These research findings are intended to support the design and optimization of these devices.

关键词： Magnetic fluid multi-physical field coupling induction pump numerical simulation liquid metal conveying

Quantitative characterization of fusion state of virgin and aged asphalt using nano-ferrous ferric oxide tracer

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Journal of Traffic and transportation Engineering(English Edition) 2024年第3期11卷 467-480页

作者： Qiang Li Song Liu Huameng Wen Zhou Zhou college of Civil Engineering Nanjing Forestry University School of transportation Southeast University

The exact evaluation of the fusion rate of virgin and aged asphalt is essential to optimize the performance of the recycled asphalt mixture. The fusion rate index was developed by tracing the distribution of tracer asphalt, which contains nano-ferrous ferric oxide（nano-Fe3O4） tracer. Laboratory fusion simulation tests were performed on three types of asphalt to obtain different fusion states, and fatigue tests were performed to evaluate the influence of the fusion rate on the fatigue life of the recycled asphalt. It was found that the tracer asphalt containing 4% nano-Fe3O4shows the optimal trace effect, and the developed fusion rate index can quantitatively characterize the influence of different factors on the fusion state of the recycled asphalt. The fusion state is closely related to the fatigue performance of recycled asphalt, and the fusion rate index can fairly evaluate its fatigue performance.The relationship between the fusion rate and the fatigue life of recycled asphalt depends on the factors that cause the fusion rate variation. Under the influence of the amount of rejuvenator, the fatigue life of recycled asphalt grows exponentially with increasing fusion rate due to enhancement of molecular motion as well as a supplement of lightweight components. Under the influence of heat preservation treatment, fatigue life increases linearly with increasing fusion rate. The proposed fusion rate index can be utilized to quantitatively characterize the fusion state of virgin and aged asphalt, thus providing a simple way to guide the practical application of recycled asphalt.

关键词： Recycled asphalt Rejuvenator Tracing technique Fusion rate Fatigue

Simulation of Underground Reservoir Stability of Pumped Storage Power Station Based on Fluid-Structure Coupling

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Computer Modeling in Engineering & Sciences 2024年第5期139卷 1381-1399页

作者： Peng Qiao Shuangshuang Lan Hongbiao Gu Zhengtan Mao Faculty of Architecture Civil and Transportation EngineeringBeijing University of TechnologyBeijing100020China college of transportation Engineering Nanjing Tech UniversityNanjing210000China

Based on global initiatives such as the clean energy transition and the development of renewable energy,the pumped storage power station has become a new and significant way of energy storage and regulation,and its construction environment is more complex than that of a traditional reservoir.In particular,the stability of the rock strata in the underground reservoirs is affected by the seepage pressure and rock stress,which presents some challenges in achieving engineering safety and stability.Using the advantages of the numerical simulation method in dealing deal with nonlinear problems in engineering stability,in this study,the stability of the underground reservoir of the Shidangshan(SDS)pumped storage power station was numerically calculated and quantitatively analyzed based on fluid-structure coupling theory,providing an important reference for the safe operation and management of the underground reservoir.First,using the COMSOL software,a suitablemechanicalmodel was created in accordance with the geological structure and project characteristics of the underground reservoir.Next,the characteristics of the stress field,displacement field,and seepage field after excavation of the underground reservoir were simulated in light of the seepage effect of groundwater on the nearby rock of the underground reservoir.Finally,based on the construction specifications and Molar-Coulomb criterion,a thorough evaluation of the stability of the underground reservoir was performed through simulation of the filling and discharge conditions and anti-seepage strengthening measures.The findings demonstrate that the numerical simulation results have a certain level of reliability and are in accordance with the stress measured in the project area.The underground reservoir excavation resulted in a maximum displacement value of the rock mass around the caverns of 3.56 mm in a typical section,and the safety coefficient of the parts,as determined using the Molar-Coulomb criterion,was higher than 1,indicating that the project as a whole

关键词： Underground reservoir fluid-structure coupling numerical simulation pumped storage power station filling and discharge

Evaluation and Influencing Factors on Particle Agglomeration in RAP

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Journal of Wuhan University of Technology(Materials Science) 2024年第1期39卷 60-68页

作者：唐伟李宁 ZHUANG Yuan ZHAN He YU Xin WU Wenxiu DING Gongying college of Civil and transportation Engineering Hohai UniversityNanjing 210098China Jiangsu Expressway Engineering Maintenance Technology Center Nanjing 211106China Jinhua Highway and transportation Management Center Jinhua 321000China

Asphalt extraction test and scanning electron microscopy(SEM) were used for analysis of agglomerations of reclaimed asphalt pavement(RAP) particles. In order to quantify the agglomeration degree of RAP, the fineness modulus ratio(FMR) and the percentage loss index(PLI) were proposed. In addition, grey correlation analysis was conducted to discuss the relationship between particle agglomerations and RAP size,asphalt content(AC), and surface area. Two indexes indicate that the agglomeration degree increases in general as the RAP size reduces. This can be attributed to that particles are prone to agglomeration in the case of higher AC. Based on the SEM images and the material composition of RAP, the particle agglomeration in RAP can be classified into weak agglomeration and strong agglomeration. Grey correlation analysis shows that AC is the crucial factor affecting the agglomeration degree and RAP variability. In order to produce consistent and stable reclaimed mixtures, disposal measures of RAP are suggested to lower the AC of RAP.

关键词： RAP particle agglomeration grey correlation analysis asphalt content

Evidence-based practices in sustainable travel behavior intervention: A knowledge graph-based systematic review

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Journal of Traffic and transportation Engineering(English Edition) 2024年第2期11卷 293-311页

作者： Jian Li Chenjie Xu Key Laboratory of Road and Traffic Engineering of the Ministry of Education College of Transportation EngineeringTongji UniversityShanghai 201804China

Sustainable travel behavior intervention is an essential strategy to promote the development of urban transportation.The interventions offer personalized strategies based on certain scenario and participants to promote its effectiveness over hard travel restrictions.However,personalized strategies may also bring about difficulties to identify the actual effect of the measures.Furthermore,based on current practice,to make full use of travel behavior interventions,it is necessary to construct a unified methodological evidencebased framework to assess the reliability and effectiveness of travel behavior intervention studies.In response to these issues,we applied evidence-based knowledge graph to the field of sustainable travel behavior interventions to help decision supporters design sustainable travel behavior interventions wisely and in turn avoid excessive use of hard travel restrictions.We introduced concept of evidence-based practice to conduct a systematic analysis concerning reliability and validity of current full volume empirical studies by dimensions of scenarios,types of interventions and targets.In addition,we took advantage of high extensivity and integrability of knowledge graph to organize evidence-based related elements.Result of the systematic analysis shows that in terms of reliability of evidence,school intervention is the best scenario,knowledge incentive is the best intervention type and promoting public transit and walking proportion are the best targets.Oppositely,the reliability of interventions in workplace,belonging to reward and threat along with aiming at changing travel patterns generally and lowering travel carbon emission need to be enhanced.From the study,various research prospects are raised to promote evidence quality in the field of travel behavior intervention implementation.As a pioneer study,our research contributes to the field of urban transportation in introducing concepts of evidence-based practice and enabling optimization and extension of our achievement via the usage of k

关键词： Evidence-based decision-making Evidence assessment Knowledge graph Travel behavior intervention Sustainable travel

Creep damage evolution process of asphalt binder based on viscoelastic characteristics

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Journal of Traffic and transportation Engineering(English Edition) 2024年第3期11卷 497-506页

作者： Xiaofei Qi Shuang Tian Liyan Shan Shuang Liu Yajie Wang School of transportation Science and Engineering Harbin Institute of Technology college of Water Conservancy & Architectural Engineering Shihezi University

The creep damage evolution of asphalt binder plays a significant role in investigating the formation mechanism of rutting. The rutting is the common distress at high temperatures for asphalt pavements. However, the reliability of existing creep damage parameters is under questioned, and these parameters cannot accurately illustrate the change of intrinsic microstructure for asphalt binder. In this paper, a new test protocol was given access to study the evolution of viscoelastic parameters during creep damage. It was completed by inserting the frequency sweep during creep test. The frequency sweep curve clusters were fitted by the generalized Kelvin-Voigt model for obtaining the change law of model parameters. Based on the change law and sensitivity analysis of model parameters,（E2+ E3）/2 was proposed as the creep damage variable. According to the curve of（E2+ E3）/2 versus loading time, two stages during the creep test could be identified: an approximate constant value in phase I and a linear decrease in phase II. Intrinsic differences about creep property of binders could be determined by this new proposed parameter. Above results not only ensure better understanding of the creep damage mechanism of binders, but also lay the theoretical foundation on predicting the anti-rutting performance of binders.

关键词： Asphalt binder Multi-stage creep test Damage variable Evolution law