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Review of Power Supply and Distribution Construction Technology for highway Electromechanical Engineering

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Journal of Electronic Research and Application 2024年第2期8卷 27-32页

作者： Li Liu China Merchants Chongqing Communications Technology Research&Design Institute Co. LTD.Chongqing 400067China

In recent years,China has made significant progress in the construction of highways,resulting in an improved highway network that has provided robust support for economic and social development.However,the rapid expansion of highway construction,power supply,and distribution has led to several challenges in mechanical and electrical engineering technology.Ensuring the safe,stable,and cost-effective operation of the power supply and distribution system to meet the diverse requirements of highway operations has become a pressing issue.This article takes an example of a highway electromechanical engineering power supply and distribution construction project to provide insight into the construction process of highway electromechanical engineering power supply and distribution technology.

关键词： highway Mechanical and electrical engineering Power supply and distribution construction technology Construction process

Analysis of the Application of Span-Bridge Technology for Building highway Tunnels that Go Over Solutional Caves

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Journal of World Architecture 2024年第1期8卷 103-107页

作者： Ruiquan Liu China Merchants Chongqing highway Engineering Testing Center CO. LTD.Chongqing 400067China

This article presents a real engineering project showcasing the application of span-bridge construction technology for building a highway that goes over a solutional cave.An overview of the project and the details of applying this technology in highway construction are provided.Besides,strategies for enhancing its construction quality are also proposed.The objective of this analysis is to improve the safety and quality of similar projects.

关键词： highway Span-bridge technology Cave penetration

Utilization of recycled solid waste as ecological reclamation materials based on plant growth experiments and soil quality analysis

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Journal of Mountain Science 2024年第3期21卷 820-834页

作者： QIN Xiaochun NI Anchen YANG Dongxiao XING Wenhu LIU Shiliang College of Civil Engineering Beijing Jiaotong UniversityBeijing 100044China Shanxi Road&Bridge Construction Group Co. LtdShanxi 030006China School of Environment Beijing Normal UniversityBeijing 111875China

During the highway construction,a large number of spoil areas will be generated while a large amount of waste slag and soil could not be rationally utilized.Besides,the vegetation recovery is slow in the spoil areas due to the soil depletion.Aiming at recycling the solid waste,the sieved engineering waste slag with local red clay and corn straw biochar was supplied to solve the problem of insufficient nutrients in engineering waste slag and soil.In addition,planting experiments of alfalfa(Medicago sativa L.)and Amorpha fruticosa L.combined with physical and chemical experiments were carried out to prove the feasibility of the novel improved substrate for the reclamation of spoil areas.The results show that the substrate's improvement effect is mainly affected by the soil to slag ratio and the biochar content.The improvement effect of soil matrix in highway spoil area decreases with the increase of the waste slag content,especially when the soil-slag ratio is less than 3,and the promotion of plants is limited.On the contrary,the improvement effect is proportional to the biochar content(3%-8%).But it is noted that the Cu and Pb in the soil will exceed the clean limit corresponding to the Nemero soil pollution index level when the biochar content is 8%.Therefore,it is recommended that the soil-slag ratio should be≥3,and the biochar content should reach 3%-5%.This research provides experimental basis and technical support for utilizing solid waste resources in the reclamation of highway spoil areas.

关键词： highway Spoil area Waste slag Modified soil Ecological reclamation

Predictive Control Model Based on the MPC Algorithm on Three Different Road Sections

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Journal of Electronic Research and Application 2024年第2期8卷 116-123页

作者： Xiaoxi Liu Xixi Zheng Shuming Zhang Zhidong Wang School of Civil Engineering and Transportation Northeast Forestry UniversityHarbin 150040Heilongjiang ProvinceChina

Predictive control is an advanced control algorithm,which is widely used in industrial process control.Among them,model predictive control(MPC)is an important branch of predictive control.Its basic principle is to use the system model to predict future behavior and determine the current control action by optimizing the objective function.This paper discusses the application of MPC in the prediction and control of the speed of vehicles to optimize traffic flow.It is a valuable reference for alleviating traffic congestion and improving travel efficiency and smoothness and provides scientific basis and technical support for future highway traffic management.

关键词： MPC algorithm Variable speed limit control highway

V2V Channel Modeling at 5.2 GHz for highway Environment

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China Communications 2022年第11期19卷 112-128页

作者： Suying Jiang Wei Wang Ibrahim Rashdan School of Information Engineering Chang’an UniversityXi’an 710064China Institute of Communications and Navigation German Aerospace Center(DLR)Oberpfaffenhofen 82234Germany

To design and evaluate vehicle-to-vehicle(V2V)communication systems in intelligent transportation system(ITS),it is important to understand the propagation mechanisms and channel models of V2V channels.This paper aims to analyze the channel models at 5.2 GHz for the highway environment in obstructed line-of-sight(OLoS)and line-of-sight(LoS)scenarios,particularly the vehicle connectivity probability derivation based on the propagation model obtained from measurement.First,the path loss(PL),shadow fading(SF),narrowband K-factor,and small-scale amplitude fading are analyzed.Results showed that the received signal magnitude follows Rice and Weibull distribution in LoS and OLoS scenarios,respectively.Second,we develop simple and low-complexity tapped delay line(TDL)models with a 10 MHz bandwidth for LoS and OLoS scenarios;in addition,we investigate the wideband K-factor,the root mean square delay spread(RMS-DS),and delay-Doppler spectrum.Third,we derive the closed form connectivity probability between any two vehicles in the presence of Weibull fading channel,and analyze the effects of Weibull fading channel and traffic parameters on connectivity.It is found that Weibull fading parameter,transmit power and vehicle density have positive impact on connectivity probability,PL exponent has negative impact on connectivity probability.

关键词： channel model connectivity highway tapped delay line model vehicle-to-vehicle

For Whom the Toll Sells

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China Weekly 2024年第1期 17-19页

作者： Chen Weishan 不详

For decades,China's extensive network of highways has largely remained toll-free However,local governments are pushing harder than ever before for tolls to heln cover costs and pull them out of debt.

关键词： highway network largely

Outlook of 2004 Chinese bus market

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中国汽车（英文版） 2004年第3期 11-13页

作者： By WANG Yunyao Secretary general of China highway Academy

highway Planning and Design in the Qinghai–Tibet Plateau of China: A Cost–Safety Balance Perspective

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Engineering 2019年第2期5卷 337-349页

作者： Chengqian Li Lieyun Ding Botao Zhong Department of Construction Management School of Civil Engineering and Mechanics Huazhong University of Science and Technology Wuhan 430074 China

Engineering designs for mountainous highways emphasize compliance checking to ensure safety. However, relying solely on compliance checking may lead designers to minimize costs at the expense of high risk indicators, since the overall risk level of the highway design is unknown to the designers. This paper describes a method for the simultaneous consideration of traffic safety risks and the associated cost burden related to the appropriate planning and design of a mountainous highway. The method can be carried out in four steps: First, the highway design is represented by a new parametric framework to extract the key design variables that affect not only the life-cycle cost but also the operational safety. Second, the relationship between the life-cycle cost and the operational safety risk factors is established in the cost-estimation functions. Third, a fault tree analysis (FTA) is introduced to identify the traffic risk factors from the design variables. The safety performance of the design solutions is also assessed by the generalized linear-regression model. Fourth, a theory of acceptable risk analysis is introduced to the traffic safety assessment, and a computing algorithm is proposed to solve for a cost-efficient optimal solution within the range of acceptable risk, in order to help decision-makers. This approach was applied and examined in the Sichuan–Tibet highway engineering project, which is located in a complex area with a large elevation gradient and a wide range of mountains. The experimental results show that the proposed approach significantly improved both the safety and cost performance of the project in the study area.

关键词： highway planning and design Cost-safety optimization Acceptable risk assessment Sichuan-Tibet highway

highway Cost Prediction Based on LSSVM Optimized by Intial Parameters

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Computer Systems Science & Engineering 2021年第1期36卷 259-269页

作者： Xueqing Wang Shuang Liu Lejun Zhang School of Mechanics and Civil Engineering China University of Mining and Technology-BeijingBeijing100083China School of Information Engineering Yangzhou UniversityYangzhou225127China

The cost of highway is affected by many factors.Its composition and calculation are complicated and have great ambiguity.Calculating the cost of highway according to the traditional highway engineering estimation method is a completely tedious task.Constructing a highway cost prediction model can forecast the value promptly and improve the accuracy of highway engineering cost.This work sorts out and collects 60 sets of measured data of highway engineering;establishes an expressway cost index system based on 10 factors,including main route mileage,roadbed width,roadbed earthwork,and number of bridges;and processes the data through principal component analysis(PCA)and hierarchical cluster analysis.Particle swarm optimization(PSO)is used to obtain the optimal parameter combination of the regularization parameter c and the kernel function width coefficientin least squares support vector machine(LSSVM).Results show that the average relative and mean square errors of the PCA-PSO-LSSVM model are 0.79%and 10.01%,respectively.Compared with BP neural networks and unoptimized LSSVM model,the PCA-PSO-LSSVM model has smaller relative errors,better generalization ability,and higher prediction accuracy,thereby providing a new method for highway cost prediction in complex environments.

关键词： highway least squares support vector machine(LSSVM) particle swarm optimization(PSO) principal component analysis(PCA) hierarchical cluster analysis