Research On Route Planning And Risk Assessment Technology Of Submarine Optical Cable Based On GIS

The submarine optical cable system carries more than 95%of the world’s international information transmission business.It is an important infrastructure and provides a strong support for promoting the development of global economy and information technology.It has broad application prospects and far-reaching strategic significance.Compared with the terrestrial optical cable system,the construction cost of the submarine optical cable system is high and the maintenance is difficult.Once a failure occurs,it will cause huge economic losses and serious social impact.Therefore,the risk assessment and routing planning and design of the submarine optical cable system are particularly important for improving the reliability of the submarine optical cable network.Traditional submarine optical cable routing planning is mainly based on expert experience.Risk assessment is difficult to quantify,and it is difficult to achieve accurate risk assessment and routing planning and design that comprehensively consider economy and reliability.Therefore,it is of great significance to establish a systematic and scientific quantitative risk assessment model for submarine optical cable routing and design a multi-objective routing planning algorithm to improve the reliability of submarine optical cable routing.Based on risk matrix and analytic hierarchy process(AHP),a quantitative risk assessment model of submarine optical cable routing is established in this paper to achieve a quantitative assessment of the reliability of submarine optical cable routing.At the same time,considering economy and reliability,a multi-objective routing model of submarine optical cable is established,and an improved ant colony algorithm based on Pareto optimal solution set is designed to realize the optimal design of submarine optical cable routing.Finally,the two models are simulated and verified based on geographic information system(GIS).The main work and research content of the thesis are as follows:1.This paper analyzes the historical damage statistics of submarine optical cable,and selects six factors including fishery activity,shipping activity,earthquake,volcano,submarine slope and submarine organism to carry out risk assessment of submarine optical cable routing,and builds a risk quantitative assessment model of submarine optical cable routing based on risk matrix and analytic hierarchy process.Based on the actual geographic information data,the risk rating of the new Trans-Pacific(NCP)International Submarine cable S3 segment route was evaluated by using geographic information system simulation.The simulation results show that the maximum risk grade score of the route is reduced from 4 to 1.9621 and the average risk grade score is reduced from 1.5336 to 1.1071,which is 27.8%lower than the original score.2.Aiming at the problem of route planning of submarine optical cable,a multi-objective route planning model with the minimum foundation construction cost and the lowest risk grade as the objectives is established,and an improved ant colony algorithm based on Pareto optimal solution set is proposed.Heuristic function,pheromone updating mechanism and state transition rules are redesigned,and Pareto optimal solution decision method is defined.The simulation results show that the quality of the algorithm is optimal when the number of ant colonies m=700,the maximum number of iterations Nc=100,pheromone factorα=1,heuristic function factor β=1 and pheromone volatile factorρ=0.4.At the same time,when the number of ant colony was 200,compared with the basic ant colony algorithm,the optimal foundation construction cost and safety grade score of the optimization algorithm were improved most significantly,which decreased by 20.37%and 38.73%,respectively.3.Modeling large-scale Marine topography based on grid method,using unit grid to store elevation value,slope,foundation construction cost and risk rating,laying a foundation for the application of submarine cable multi-objective routing planning model.Taking part of the Atlantic Ocean as an example,the grid map is generated based on GIS,and the improved ant colony algorithm is used to solve the model.Fourteen feasible routing schemes are obtained,among which the Pareto optimal routing solution set contains three routes,and the Pareto optimal solution judgment method is used to select the best route of the Pareto optimal routing solution set.Simulation results show that the optimal route selected in this paper significantly avoids the region with high foundation construction cost and risk rating,which provides reference for decision makers in planning.