Research On The Robustness Of Eco-Industrial Symbiosis Network

Eco-Industrial Park(EIP),as carriers of eco-industry clusters,have played an active role in solving resource shortages and environmental pollution.It is widely recognized by countries around the world.The construction of EIPs abroad started earlier than in China,and accumulated a great deal of construction practice and management experience,which is of great significance for the construction of EIPs in China.Although there are many successful cases in China,some problems have been gradually exposed during developing.The most obvious problem,the instability phenomenon,is mainly manifested in the fragile of eco-industrial chains easy to break,and lack of anti-interference ability.In industrial ecology,the Eco-Industrial Symbiosis Network(EISN)is the main organizational form of enterprise ecological cooperation in EIPs,and it is the core content of the EIP construction process.Whether symbiosis networks can maintain normal operation is related to the success or failure of EIP construction.EISN is a complex system.The relationship among the internal members of the system is complex.When the system is affected by external or internal uncertainties,how to ensure the smooth flow of information,materials,and energy in the system becomes the key for stable operation of the network system.Therefore,studying the robustness of the EISN system has important theoretical and practical significance for the local government or related departments to guide the construction of EIPs.Based on the complexity,openness,nonlinearity,and other complex network characteristics of the Eco-Industrial Symbiosis Network(EISN),using topological theory,percolation theory,and structural entropy model,a complex network theory from the perspective of quantitative methods,EISN Robustness Analysis and Optimization Methodology System,has been built.This system takes the structural robustness index and performance robustness index as the analysis model,constructs the EISN system robust optimization index and optimization method based on the percolation theory.It quantitatively analyzes the improvement of the robustness of the EISN network before and after optimization.The structural entropy model was used to verify the robust optimization results of the EISN system.According to the empirical research on two typical cases of Kalonburg EISN and Guigang EISN,the natural connectivity of Kalinburg EISN in the initial state is 1.7487,and the network efficiency is 0.5614.The natural connectivity of EISN in Guangxi Guigang is 1.4959,and the network efficiency is 0.3482.From the comprehensive consideration of structural robustness and performance robustness,the robustness of Kalundborg is better than the robustness of Guangxi Guigang.In addition,although there are certain differences in the robustness of different EISNs,there are the same or similar robust expressions under different attacks.That is to say,it has good resistance to random failure,but it has greater vulnerability to intentional destruction.lt is concluded that as long as the key enterprise does not fail,the EISN system has a strong self-regulation capability.The percolation theory is used to optimize the robustness of Guangxi Guigang EISN.Enterprises with small degree of network nodes are properly supplemented to form a "backup core" enterprise.It can not only effectively reduce the dependence of other enterprises on key enterprises,but also further improve the robustness of the EISN system.In order to further verify the reliability of the optimization results,the structural entropy model was used to quantitatively analyze the EISN before and after optimization.It is shown that after optimization,the structural entropy R of Guigang EISN decreases from 0.2600 to 0.2529,which is a decrease of 0.0071,indicating that the orderliness and robustness of the system have been improved.Therefore,this kind of EISN optimization design method for the "back-up core" company to supplement the chain has a very good promotion value and practical significance for the actual construction and operation of EIPs in China.