An Optimization Method For Highway Network Planning Based On Theory Of Transportation And Tourism Integration

With the increasing demand for tourism,the tourism service capabilities of the highway network have become critically important.However,the conventional methods of highway network planning lack systematic consideration of tourism resources,resulting in insufficient integration between transportation and tourism development.This thesis proposes an optimization method for the highway network planning based on the theory of integrating transportation and tourism development to address this issue.This thesis first analyzes the concept and connotation of integrating transportation and tourism development based on the characteristics of transportation and tourism.It proposes the use of using the adaptability of integrating transportation and tourism development as a measure of the degree of integration between them.To address the issue that existing research on the integration of transportation and tourism development is overly focused on macro development scales,this thesis considers the influencing factors from the perspective of the integration between tourism attractions and the end of the highway network.Three aspects,namely the connectivity of tourism attractions,the accessibility of tourism attractions,and the ability of the highway network to resist external disturbances,are selected as the influencing factors of the adaptability of integrating transportation and tourism development to provide optimization direction and theoretical basis for future research.Based on the concept and characteristics of scenic spot clusters,this thesis uses geographic spatial division as the method for dividing scenic spot clusters.The buffer analysis function in Trans CAD software is used to achieve the division of scenic spot clusters.Five indicators,namely the number of tourists visiting the scenic spot,the rating of the scenic spot,the number of ratings,the popularity of the scenic spot,and the level of the scenic spot,are selected to construct a comprehensive competitiveness index evaluation model for scenic spots.Based on the division results of the scenic spot cluster,the comprehensive competitiveness index of the scenic spot is used as the characteristic quantity.The centroid method is used to construct a potential tourism hub node location selection model,and a solution algorithm is given.By adding new tourism hub nodes to the existing highway network,the topological structure of the highway network can be enriched to provide a basic support for the highway network optimization model in subsequent research.Based on the influence factors of the adaptability of the integrated development of transportation and tourism,and combined with the characteristics of them,a Bi-level multiobjective nonlinear integer programming model was constructed to optimize the highway network.The upper-level model considers the minimum total construction funds of the highway network,the optimal weighted accessibility of highway network scenic spots based on the perspective of overall tourism,the minimum vulnerability of the road connecting scenic spots under the impact of large passenger flow,the constraint of the saturation mileageweighted sum of road segments in the regional highway network,the constraints on the number and quality of end connections of tourist attractions.The lower-level model is based on the traffic assignment problem under user equilibrium theory.A hybrid algorithm combining NSGA-II algorithm with Frank-Wolfe algorithm was introduced to solve the optimization model.The algorithm was designed and tested through algorithmic design and experiments.Finally,the optimization model was applied to the highway network in Dali City,Yunnan Province as a case study,and the optimization results of the highway network were obtained.The analysis of the optimization results showed that both two target functions(function 2:the optimal weighted accessibility of highway network scenic spots based on the perspective of overall tourism,function 3: the minimum vulnerability of the road connecting scenic spots under the impact of large passenger flow)reflecting the adaptability of the integration of road transportation and tourism development were significantly improved after optimization,with the optimization ratio on target function 2 maintained at around 90% and the optimization ratio on target function 3 maintained at above 99%.Among the three Pareto optimal solutions obtained,each has its own advantages and disadvantages.Solution 1 has the lowest construction cost but the worst optimization effect on target function 2,and the optimization effect on target function 3 is between Solution 2 and Solution 3.Solution 2 has the best optimization effect on target function 2,with a higher construction cost than Solution 1 but lower than Solution 3,but the optimization effect on target function 3 is the worst.Solution 3 has a moderate optimization effect on target function 2,the best optimization effect on target function 3,but the highest construction cost.Based on existing studies,this thesis proposes an highway network optimization method that incorporates relevant factors related to the integration of tourist attractions and the end-toend connection of the highway network in the planning objectives,which reflects the integration of transportation and tourism development more deeply.Before determining the highway network to be optimized,new tourism hub nodes were added,which maximized the enrichment of the network topology.The NSGA-II algorithm was used to solve the upperlevel multi-objective optimization model,avoiding the problem of setting weights when converting multiple objectives into a single objective,and enabling the optimization process to simultaneously consider multiple objectives.Case analysis shows that this optimization method is scientifically and practically feasible,and has certain guiding significance for highway network planning under the context of considering the integration of transportation and tourism development.