Target recovery of the economic system based on the target reinforcement path method.

An effective and stable operation of an economic system leads to a prosperous society and sustainable world development. Unfortunately, the system faces inevitable perturbations of extreme events and is frequently damaged. To maintain the system's stability, recovering its damaged functionality is essential and is complementary to strengthening its resilience and forecasting extreme events. This paper proposes a target recovery method based on network and economic equilibrium theories to defend the economic system against perturbations characterized as localized attacks. This novel method stimulates a set of economic sectors that mutually reinforce damaged economic sectors and is intuitively named the target reinforcement path (TRP) method. Developing a nonlinear dynamic model that simulates the economic system's operation after being perturbed by a localized attack and recovering based on a target recovery method, we compute the relaxation time for this process to quantify the method's efficiency. Furthermore, we adopt a rank aggregation method to comprehensively measure the method's efficiency by studying the target recovery of three country-level economic systems (China, India, and Japan) for 73 different regional attack scenarios. Through a comparative analysis of the TRP method and three other classic methods, the TRP method is shown to be more effective and less costly. Applicatively, the proposed method exhibits the potential to recover other vital complex systems with spontaneous recovery ability, such as immune, neurological, and ecological systems.

Structural analysis of indirect carbon emissions embodied in intermediate input between Chinese sectors: a complex network approach.

The indirect carbon emission embodied in the intermediate input is also an important indicator of assessing a producer's carbon emissions. Structural analysis of indirect carbon emissions is helpful to understand the responsibilities between producers and pay efforts to key areas. The aim of this study is to analyze indirect carbon emissions embodied in intermediate input between sectors and explore the distribution structure of indirect carbon emissions flow network (namely, ICEFN). Based on the modified input-output model and complex network theory, this study constructed four directed and weighted ICEFNs with 28 sectors from 1997 to 2012. The results show that indirect carbon emissions between sectors are significantly higher than direct carbon emissions, accounting for nearly 70% of the total carbon emissions of China. Second, we analyzed the embodied carbon emission intensity (namely, ECI) of each sector. Although the ECI has been decreasing over time, the decrease has increasingly diminished, which indicates that the additional carbon emission reductions are more difficult. Third, we identified the key sectors which play different roles in the ICEFNs. Meanwhile, we studied the key paths which show more closed relationships between some sectors in ICEFNs. Finally, based on the above analysis, we made policy recommendations.