Study on the Resilience Measurement of the New Energy Vehicle Industry Chain

: In the context of economic globalization, industry chain resilience helps to improve the ability of the new energy vehicle industry to cope with external risks. Therefore, based on the CSCE principle, this paper utilizes the entropy weight method to construct a comprehensive evaluation index system for the resilience of the new energy vehicle industry chain, aiming to quantify its level of resilience. It is found that resistance is the most important (33.53%), adaptive resilience is the second most important (28.66%), and renewal (or resumption) is the least important (13.97%) in this evaluation index system. Therefore, it assists enterprises and government departments in making decisions on replenishing and strengthening the chain, reducing the risk of the industry chain, and realizing the high-quality development of the industry chain.


Introduction
The new energy industry is not only an important basis for measuring the level of high-tech development of a country and a region [1,2], but it is also a frontier of international strategic competition.Developed countries and regions worldwide consider the development of new energy a trend in science and technology, promoting it as an important initiative for industrial restructuring [3].Currently, the global new energy vehicle industry is accelerating.Europe, the United States, and Japan regard new energy vehicles as the pioneering industry of a new round of scientific and technological revolution and the main carrier for garnering support [4].Against the backdrop of its commitment to achieving a carbon peak by 2030 and carbon neutrality by 2060 in response to global climate change [5], China has identified new energy vehicles as a breakthrough in the development of high-end industries and as a crucial measure to promote the realization of "Dual Carbon Goals" and the construction of a strong advanced manufacturing country.The new energy vehicles industry has become a significant tool in promoting the achievement of the national breakthrough in the development of high-end industries [6], and new energy vehicles have taken an important role in promoting the realization of the national "Dual Carbon Goals" and the advancement of manufacturing capabilities [7].However, regional disruptions in the industrial chain caused by the trade war between the United States and China, global supply and demand uncertainty, natural disasters, social unrest, terrorism, and financial crises have increased the uncertainty in the global political situation [8].Localized disruptions can be mitigated by support from neighboring regions, reducing the risk of industry chain breakage [9].Especially after the outbreak of the COVID-19 pandemic, regional governments have taken various measures to increase the resilience of healthcare systems.However, the physical isolation and blockades resulting from these measures have had a devastating impact on the logistics industry [10,11], According to Table 1, the Changzhou new energy vehicle industry chain has developed the following advantages: First, the core industry chain of the new energy vehicle industry is relatively complete [17].The core of the new energy vehicle industry is the whole vehicle and power battery, with leading enterprises such as BYD, BAIC BJEV, and Li Auto, as well as new car-making forces, establishing their production bases in Changzhou.Changzhou clusters power battery and ancillary enterprises covering upstream raw materials, functional materials, and manufacturing equipment; midstream battery cores, electric motors, and electric control systems; and downstream vehicle recycling, laddering, energy storage, testing, and evaluation.This expanded application covers 94% of the industry chain, with China's highest production capacity.
Second, the core parts and components are comprehensively supported, with leading effects in charging pile gas permeability enterprises [18].Changzhou has enterprises covering the body system field, including body, interior and exterior decoration, air conditioning systems, and car seats.Companies such as XINGYU, Deepland Technology, Bestar Holding, Kuangda Technology Group, and Star Charge are core enterprises in China's new energy vehicle industry chain [19,20].Notably, Star Charge is China's largest charging pile service provider and shares its platform with over 60 vehicle enterprises to provide charging pile services [20].These "anchor firms" [21] in the new energy vehicle industry chain continue to attract smaller innovative companies to gather in Changzhou, continuously improving and expanding the new energy vehicle industry chain.
Figure 1 presents a line chart illustrating the annual new energy vehicle production shares from 2017 to 2023.The horizontal axis (X-axis) represents years, while the vertical axis (Y-axis) indicates the annual new energy vehicle production shares.Line a1 represents the share of Changzhou's new energy vehicle production in Jiangsu Province's new energy vehicle production and line a2 represents the share of Changzhou's new energy vehicle production in China's new energy vehicle production.Each data point on each line corresponds to the new energy vehicle production shares for that particular year.Notably, there is a significant spike in 2019, which can be attributed to the implementation of Changzhou's "New Energy Capital" strategy.It is important to note that while the line chart provides a clear visual representation of the share trends, it does not account for external factors that may have influenced shares, such as global macroeconomic uncertainty and natural disasters.Overall, the chart supports the argument that Changzhou's new energy vehicle industry chain has experienced sustained growth over the analyzed period.
external factors that may have influenced shares, such as global macroeconomic uncertainty and natural disasters.Overall, the chart supports the argument that Changzhou s new energy vehicle industry chain has experienced sustained growth over the analyzed period.
New energy vehicles, spare parts, and power batteries have become the pillars of Changzhou s new energy economic development.During the COVID-19 epidemic, the new energy vehicle industry chain in Changzhou also faced a production chain crisis.Based on this, this study aims to assess the resilience and adaptive capacity of the new energy vehicle industry supply chain in the face of external risk shocks.New energy vehicles, spare parts, and power batteries have become the pillars of Changzhou's new energy economic development.During the COVID-19 epidemic, the new energy vehicle industry chain in Changzhou also faced a production chain crisis.Based on this, this study aims to assess the resilience and adaptive capacity of the new energy vehicle industry supply chain in the face of external risk shocks.

Literature Review 2.2.1. The Concept of Resilience
The concept of resilience has been widely explored and is defined and understood differently depending on the research context and field.Initially, the term resilience was used in physics to study the ability of a material to absorb energy during plastic deformation and rupture [22,23].Higher resilience means a lower probability of the material undergoing brittle fracture.In 1973, Holling introduced the concept of resilience into ecology, which measures the ability of natural systems to maintain their original state or recover quickly when faced with external shocks such as human or natural factors [24].Holling's study is regarded as the origin of modern resilience theory [25].The concept of resilience has been introduced into multiple disciplines to measure a system's ability to continuously adapt and recover in the face of diverse, multi-scale disturbances, maintaining a dynamic balance throughout the process.Reggiani et al. introduced resilience into the field of economic research, proposing that resilience can explain the key elements of different regions that perform differently under the influence of external shocks [26].This concept gained significant attention, especially after the international financial crisis in 2008, where different recovery performances of various economies highlighted the importance of resilience.Resilience refers to the ability to cope with unexpected disruptions caused by natural disasters or terrorist attacks and quickly return to normal operations [27,28].Martin proposed that resilience is categorized into four dimensions as follows: resistance, adaptive resilience, renewal, and re-orientations.This framework has been widely adopted by scholars and is extensively used in the economic field to study economic resilience [29,30].
Economic resilience refers to the ability of an economic entity to adjust its development path when facing and resisting external shocks or uncertain risks [31].When the research subject is an economic entity at the regional level, economic resilience evolves into regional economic resilience [32].This concept considers how the economic system resists and adapts to external disturbances and shocks within special geographical and socio-economic contexts [32][33][34][35].Regional economic resilience focuses particularly on the continuous adaptation and adjustment of the internal social, economic, and political structures of the region, as well as its ability to recover after suffering economic shocks or the capacity to depart from the existing growth model and choose a better path [29,32,36].Regional economic resilience represents the region's adaptability, innovation, and sustainability [35,37].
The concept of supply chain resilience was first proposed by Rice and Caniato [28], and its formal definition was first proposed by Christopher and Peck [38].Supply chain resilience is the adaptive capacity of a supply chain to prepare for unforeseen events, respond to disruptions, and recover from them by maintaining continuity of operations at the required level of connectivity and control over structure and function [27,39].Chain resilience is the adaptive capacity of the system to respond to disruptions in a better way and even gain an advantage from such events [40].Other scholars categorize industry chain resilience according to the natural disasters or human factors that lead to the disruption of the industry chain [41,42].
Industrial chain resilience is both an important component of economic resilience and a part of regional resilience [27].According to the hierarchical nature of the concept of resilience, industry chain resilience can also be divided into three levels as follows: the ability of enterprises in the industry chain to quickly recover and adapt to supply chain disruptions after facing disruptive shocks, the ability of resilient industrial supply chains to anticipate business disruptions in the industry chain and restore the supply chain to a good state of production and operation quickly, thus generating competitive advantages [43].In other words, resilient industrial supply chains manage the adaptive capacity of supply chain disruptions by bending, which is conducive to maintaining or increasing the competitive advantage of the industrial chain [44].
For firms in the chain, resilience is an important capability for mitigating traditional risks [45].Resilience entails addressing unexpected risks in a holistic manner and preventing localized risks from propagating through the system to other elements and components.Safeguarding the entire system, along with its behavior and function, is critically important.

The Concept of Vehicle Industry Chain Resilience
Vehicle industry chain resilience refers to the ability of enterprises in the vehicle industry supply chain to prevent the industry chain from breaking and to recover to its original state after facing internal and external sudden and destructive events.It also includes promoting the industry chain or the supply chain to extend to higher value-added activities and strengthening the ability of the industry supply chain to be autonomous and controllable [43,46].According to Martin's [30] application of resilience in economic and social fields, vehicle industry chain resilience consists of the following four forces: resistance, adaptive resilience, renewal, and re-orientations.Resistance is the primary focus and the foundation of the other three forces.When the industrial supply chain is disrupted by internal and external factors, it must cope, resist, and not be overwhelmed by the impact.This is the first layer of expression of the resilience of the new energy vehicle industrial chain.
Adaptive resilience is the key to supporting the other three forces.When the industrial chain faces interference or impact, it can still recover and adapt through self-regulation and recovery abilities to promote the adaptability and stability of the industrial supply chain.This is the second expression layer of the resilience of the new energy vehicle industry chain.Autonomous control and leading competitiveness are the support, which demonstrates the strength of the other two forces.When the industry chain faces interference or impact, enterprises in the industry chain can anticipate, prejudge, and prevent disruptions in advance.These four forces are an organic whole-interconnected, complementary, mutually reinforcing, and indispensable.For example, after the outbreak of the COVID-19 epidemic in 2019, regional governments adopted corresponding methods of treatment methods, and these management policies were introduced because of logistics factors, employee factors, or other factors that caused automotive suppliers to be unable to deliver auto parts on time and in quantity.As a result, automotive manufacturers had to reduce their production volumes or even suspend production.

Measurement of Vehicle Industry Chain Resilience
Vehicle industry chain resilience is a new and important dimension of system performance under uncertainty, consisting of resilience-enhancing features that improve the system's ability to absorb, adapt, and recover itself after a disruption [46][47][48].The resilience of the industry supply chain can be categorized into four distinct levels as follows: enhanced industry supply chain resilience, industry supply chain resilience capacity, supply chain vulnerability and recoverability, and overall industry supply chain resilience.The bottom layer is enhanced industry supply chain resilience, which consists of the manufacturing industry's residual inventory and standby inventory.Enhanced industry supply chain resilience features constitute the resilience of the industry supply chain, including absorption, adaptation, and recovery capacity.The vulnerability and recoverability of the industrial supply chain is a function of its recovery capacity, where a supply chain with higher recovery capacity needs less effort to return to a normal state, while a supply chain with less recovery capacity requires more effort to return to a normal state.The industrial chain resilience is located at the top level of the structure and is a function of the vulnerability and recoverability of the industrial chain.

Factors Influencing Vehicle Industry Chain Supply Chain Resilience
The factors that influence vehicle industry supply chain resilience are (1) information technology [49][50][51].In the vehicle industry, DSC technology is widely used to communicate effectively with the help of data among supply chain entities such as dealers, original equipment manufacturers, suppliers, and service providers.The role of digital supply chain technology in vehicle supply chain resilience is to improve the supply chain performance objectives of companies in the vehicle industry [48,52].A questionnaire survey of practitioners from vehicle supply chain entities such as automotive original equipment manufacturers (OEMs), Tier 1 component manufacturers, and leading logistics providers in the emerging markets of the Asia-Pacific region argues that digital technology moderates supply chain resilience in the vehicle industry through digital supply chain technological capabilities, which is conducive to the achievement of industry chain performance objectives.
(2) Localized supply sources.One of the best strategies in the vehicle industry to mitigate the risks associated with NCCP is to develop localized sources of supply [12,21,[49][50][51][53][54][55][56].If sourcing (and processing) is localized in the same region to meet local demand, it reduces supply chain integration.As a result, the risk of disruption can be contained within the region because risk events do not spread from one region to another [54,56,57].
(3) Relationships with multinational enterprises.TNCs have the potential to play a key role in situations of natural disasters [51].Foreign TNCs and local firms in host countries interact through input-output linkages.When natural disasters hit local firms hard, thereby increasing the cost of sourcing local intermediate inputs, most TNCs may leave the host country.However, they are likely to stay if they have close relationships with local suppliers and if the trade costs of importing foreign intermediates are low [49,54].

The Impact of the COVID-19 on Industry Chain Resilience
The most serious impact of the COVID-19 pandemic on the global industrial chain was the widespread supply chain disruption because of major upheavals in manufacturing, processing, transportation, and logistics [58][59][60], with food and healthcare supply chains receiving much attention [61].Academics have begun to focus on the sustainability and agility of the chain to support organizational recovery decisions [58,[62][63][64][65].The theoretical foundations of COVID-19 and industrial supply chain research include the theory of constraints [66], the theory of dynamic systems [62][63][64][65], and the theory of information control and communication [62].All scholars agree that the solution to increasing the resilience of supply chains and reducing the risk of GSCs is to increase their resilience across various industrial sectors [60].

Building a Comprehensive Evaluation Index System for the Resilience of the New Energy Vehicle Industry Chain
Industrial chain resilience encompasses the functions of planning and preparing for future crises, as well as adapting to changes and disruptions [67].Furthermore, the industrial chain is a complex system.To fully comprehend it, one must examine both the characteristics of its individual components and the outcomes of their interactions over time.The industry chain, at the meson level, is the emergent result of various interactive processes of micro enterprises and is a process-dependent system result.Based on this, there is a complexity assumption embedded in the resilience of the industrial chain, and complexity is not always clearly defined or developed [13,68].The core feature of the new energy vehicle industry chain is the concentration of R&D in OEMs and Tier 1 supply companies, driven by strong competition and exclusivity strategies.Based on this, this paper uses a comprehensive indicator system approach, based on the CSCE principle (Comprehensiveness, Systematicity, Credibility, Executability), from the industry perspective of the new energy vehicle industry supply chain.This constitutes the new energy vehicle industry chain resilience evaluation as a whole by multiple indicators in accordance with the sequential logical progression of the relationship.
Specifically, according to Martin [30], new energy vehicle industry supply chain resilience is decomposed into four first-level indicators as follows: resistance (A1), adaptive resilience (A2), renewal (A3), and re-orientations (A4).These are then further disassembled according to the key factors of the first-level indicators, ultimately resulting in the comprehensive evaluation index system for new energy vehicle industry chain supply chain resilience.
Resistance focuses on the industry chain's resistance to external perturbations, as well as the speed and degree of its recovery, returning to the equilibrium state or path before the shock.Resistance (A1) is measured by the industrial scale (B1) and industrial efficiency (B2), which define the industrial scale and efficiency of the new energy vehicle industry chain; the resilience of the new energy vehicle industry chain is calculated by comparing scale and efficiency.Among these, the larger the industrial scale of the industry chain, the stronger the ability to resist external changes and the greater the resilience of the industry chain [37].The general measures of the industrial scale include industrial value added, the industrial value-added growth rate, industrial coverage, and the industrial employment scale.The greater the profitability of the enterprises in the industry chain, the greater the sustainable competitive advantage and the greater the industry chain resilience [69].Industrial efficiency is generally measured by corporate profits [70] and corporate tax payments.
Adaptive resilience (A2) is the ability of a chain system to maintain its core performance in the face of external shocks by adapting its structure, function, and organization to accommodate changes in order to bounce forward.Adaptive resilience is characterized by tolerating the certainty in progress and developing a framework suitable for adapting to new conditions and goals [71].If the supply chain can adapt easily, it can return to its original or enhanced state after a disruption.Adaptive resilience is more influential than resistance because it is more sustainable and effective in the context of future uncertainty [72].
Adaptive resilience consists of the following three dimensions: market position, human capital, and industry contribution.Market position is associated with both the financial capability of firms in the supply chain [73] and an increase in market share [70].The stronger the market position, the more helpful it is in maintaining the relationship with the customer after an unforeseen event [45,74].Market position is measured using the number of enterprises above scale in the new energy vehicle industry chain, the total amount of assets in the industry chain, and the business revenue of enterprises in the industry chain.
Human capital is a key factor in enhancing supply chain resilience [42].Human capital encompasses two main aspects.First, it includes employees' abilities to analyze, monitor, and control key supply chain points through the assessment of large volumes of information [71,75].Second, it involves employees' existing learning capabilities and ongoing training, which foster flexibility, competence, and work-based emotional well-being.
Renewal (A3) is the degree of renewal or recovery of the regional growth path prior to the shock, emphasizing the magnitude of the perturbation that the system can withstand before it enters a new state or equilibrium (i.e., a change in form, function, or location).The primary factors influencing renewal are technological absorptive capacity and high-level productive services, both of which positively impact renewal.Technological absorptive capacity refers to the comprehensive ability of the industrial chain to engage in technological learning, collaboration, and transformation.The stronger the technology absorptive capacity, the more conducive it is to the advantages of technological spillovers and reinnovation, which helps improve the resilience of the industrial chain [76,77].High levels of services through near-neighborhood or short-distance intermediate products, as well as high-quality financial services, help improve industry chain resilience [77][78][79].
Re-orientation (A4) is real resilience.Firms in the chain are constantly innovating, creating new products and markets, and staying ahead of competitors, which is an important part of increasing the resilience of the chain [80].Technological innovation is the core element of modern economic growth and an important source of enhancing the resilience of the new energy vehicle industry chain [77,81].The inputs and outputs of technological innovation directly measure the leading competitiveness of the industry chain, and a strong innovation system is a major factor in the resilience of the industry chain [77].

Weight Measurement of the New Energy Vehicle Industry Chain Resilience Evaluation Index System
Considering the internal complexity of new energy vehicle industry chain resilience and the outside uncertainty, this study adopts the entropy method to determine the weights of the index system.In information theory, entropy is a measure of uncertainty [82].The larger the amount of information, the smaller the uncertainty and the smaller the entropy; the smaller the amount of information, the larger the uncertainty and the larger the entropy.According to the characteristics of entropy, we can calculate the entropy value to judge the randomness of an event and the degree of disorder.We can also use the entropy value to judge the degree of dispersion of a certain indicator; the greater the degree of dispersion of the indicator, the greater the impact of the indicator on the comprehensive evaluation (weight), and the smaller the value of its entropy.The entropy weight model is divided into four parts, i.e., initial matrix construction, data standardization processing, information entropy processing of each indicator, and determining the weights of each indicator.
The specific steps of measurement are as follows: Step 1: Construct the new energy vehicle industry chain resilience evaluation matrix X.According to the 2020-2022 Changzhou new energy vehicle industry chain data, there is an evaluation matrix X = (X 1 , X 2 , X 3 ) representing the value of the Kth indicator of the evaluation object in the ith year.Specifically, there are Step 2: Complete data normalization.The data are standardized using the extreme value operation algorithm.The setting Y ik represents the value after standardization of the Kth indicator of the evaluation object in the ith year.
Step 3: Solve the information entropy processing of each indicator.As can be seen in Table 2, the comprehensive evaluation index system for the resilience of the new energy vehicle industry chain is constructed by 29 index layers.According to the definition of information entropy in information theory, E k is set as information entropy, that is,  Step 4: Determine the weight of each indicator.According to the formula of information entropy, the information entropy of each indicator is calculated as E 1 , E 2 , . . ., E 29 .w k is set as the weight of each indicator, and the weight of each indicator is calculated by information entropy as Finally, the relevant data of Changzhou's new energy vehicle industry chain are organized from 2020 to 2022, and the entropy value method to is used measure the weight results, as shown in Table 3.

Changzhou New Energy Vehicle Industry Chain Supply Chain Resilience Evaluation
Based on the weights assigned to the indicators in each tier of the new energy vehicle industry chain resilience, and utilizing the data from the new energy vehicle industry chain in Changzhou from 2020 to 2022, we employ the weighted summation method to construct a resilience index for this industry chain.The weighted summation method is a quantitative technique that aggregates individual values into a composite measure, where each value is assigned a weight that reflects its relative importance.The specific steps are as follows: Step 1: Complete new energy vehicle industry chain resilience indicator data standardization.The extreme value method is used to map the indicator data values within the range [0, 100].g ik is set as the mapped value of the ith indicator in the kth year after mapping, resulting in a 3 × 29 mapping matrix G = |g ik |.
Step 2: Let Z hk be the final score for each level h indicator.This results in the following Eq: Table 4 shows the industry chain resilience score calculated by using the 2020-2022 Changzhou new energy vehicle industry chain supply chain data.Changzhou's new energy vehicle industry chain supply chain resilience soared during the study period, with an average annual growth rate of 53%.When divided into the weights and scores of the comprehensive resilience evaluation index system, the weights and scores of the first-level indexes of the comprehensive resilience evaluation show that the indexes that are closest to the ideal state are resistance and renewal (Figures 2-4).
Among the secondary indicators, the human capital indicator, whose actual score is approximately equal to the weighted score, is the best performer among all the secondary indicators.The indicators with large differences include economic scale, industrial contribution, and scientific and technological innovation output.
Among the third-level indicators, the indicators including the employment scale of the new energy vehicle industry (C4), total tax payment of EaDS in the new energy vehicle industry (C6), total assets of the new energy vehicle industry (C8), the loan balance of financial institutions at year-end (C21), market capitalization of listed enterprises in the industry (C22), and industrial patent grants (C26) are higher than the weighted scores, which indicates that they are close to the ideal state.However, the indicators including the growth rate of the value added of the new energy vehicle industry (C2), new energy vehicle industry coverage (C3), the total profit of EaDS in the new energy vehicle industry (C5), the number of EaDS in the new energy vehicle industry (C7), the contribution ratio of the total assets of EaDS (C12), profitability coverage of EaDS (C14), the number of industrial professionals and technicians (C23), the number of new projects approved in the industry (C24), the average growth rate of the output value of industrial high-tech enterprises (C27), energy consumption per unit GDP (C28), and sales of new industrial products (C29) need to be further improved and developed.Table 4 shows the industry chain resilience score calculated by using the 2020-2022 Changzhou new energy vehicle industry chain supply chain data.Changzhou s new energy vehicle industry chain supply chain resilience soared during the study period, with an average annual growth rate of 53%.68 When divided into the weights and scores of the comprehensive resilience evaluation index system, the weights and scores of the first-level indexes of the comprehensive resilience evaluation show that the indexes that are closest to the ideal state are resistance and renewal (Figures 2-4).Table 4 shows the industry chain resilience score calculated by using the 2020-2022 Changzhou new energy vehicle industry chain supply chain data.Changzhou s new energy vehicle industry chain supply chain resilience soared during the study period, with an average annual growth rate of 53%.68 When divided into the weights and scores of the comprehensive resilience evaluation index system, the weights and scores of the first-level indexes of the comprehensive resilience evaluation show that the indexes that are closest to the ideal state are resistance and renewal (Figures 2-4).Among the secondary indicators, the human capital indicator, whose actual score is approximately equal to the weighted score, is the best performer among all the secondary indicators.The indicators with large differences include economic scale, industrial contribution, and scientific and technological innovation output.
Among the third-level indicators, the indicators including the employment scale of the new energy vehicle industry (C4), total tax payment of EaDS in the new energy vehicle industry (C6), total assets of the new energy vehicle industry (C8), the loan balance of financial institutions at year-end (C21), market capitalization of listed enterprises in the industry (C22), and industrial patent grants (C26) are higher than the weighted scores, which indicates that they are close to the ideal state.However, the indicators including the growth rate of the value added of the new energy vehicle industry (C2), new energy vehicle industry coverage (C3), the total profit of EaDS in the new energy vehicle industry (C5), the number of EaDS in the new energy vehicle industry (C7), the contribution ratio of the total assets of EaDS (C12), profitability coverage of EaDS (C14), the number of industrial professionals and technicians (C23), the number of new projects approved in the industry (C24), the average growth rate of the output value of industrial high-tech enterprises (C27), energy consumption per unit GDP (C28), and sales of new industrial products (C29) need to be further improved and developed.

Discussion
According to the existing research related to the resilience of the industrial chain, most measurements of industrial chain resilience are based on theory or a single indicator [12,84,85].Therefore, we construct a comprehensive evaluation index system of new energy vehicle industry chain resilience to analyze the resilience of the new energy vehicle industry chain in Changzhou, based on Martin s [30] resilience-related research.
Our first achievement is the development of a comprehensive evaluation index system for assessing the resilience of the new energy vehicle industry chain.This system comprises four primary index components including resistance, adaptive resilience, renewal, and re-orientation.These components are structured in a sequentially progressive relationship.
The weight distribution of the new energy vehicle industry chain comprehensive resilience evaluation index shows that resistance has the largest weight (33.53%).Within the framework of resilience, resistance is the first line of defense and belongs to the basic and

Discussion
According to the existing research related to the resilience of the industrial chain, most measurements of industrial chain resilience are based on theory or a single indicator [12,83,84].Therefore, we construct a comprehensive evaluation index system of new energy vehicle industry chain resilience to analyze the resilience of the new energy vehicle industry chain in Changzhou, based on Martin's [30] resilience-related research.
Our first achievement is the development of a comprehensive evaluation index system for assessing the resilience of the new energy vehicle industry chain.This system comprises four primary index components including resistance, adaptive resilience, renewal, and re-orientation.These components are structured in a sequentially progressive relationship.
The weight distribution of the new energy vehicle industry chain comprehensive resilience evaluation index shows that resistance has the largest weight (33.53%).Within the framework of resilience, resistance is the first line of defense and belongs to the basic and important components [85].It helps the system to resist external impacts and reduces the possibility of damage.A system with high resistance can avoid or mitigate negative impacts more effectively.The second is adaptive resilience (28.66%), which focuses on improving the system's resistance to future disruptions through adaptive changes and is the first level of industry chain resilience [72].
According to the weights of the secondary indicators, the main influencing factors of the resilience of the industrial chain are the economic scale (22.35%), industrial contribution (15.07%), and scientific and technological innovation output (16.1%).A larger economic scale usually implies a more stable industrial chain involving more enterprises, products, and markets, which reduces industrial chain risks and is able to withstand market fluctuations and shocks [86].Industries with higher industry chain contributions tend to be the pillars of the regional economy, directly affecting the stability and growth potential of the regional economy.Enterprises in these industry chains have stronger financial strength and risk management ability, which can provide stable support for the industry chain in the face of market fluctuations and external shocks [86].Scientific and technological innovation output measures the level of scientific and technological innovation, which improves the security and stability of the industrial chain in two ways [87][88][89].
On the one hand, strengthening basic and applied research solves key technological problems, improves the independent innovation ability of key links in the industrial chain, and enhances the independent and controllable nature of the industrial chain [80].On the other hand, scientific and technological innovation identifies potential risks in the industrial chain in advance and reduces the impact of potential risks through technological improvement and new product development [77].
According to the weights of the third-level indicators, the main influencing factors of the resilience of the regional industrial chain are the value added of the new energy vehicle industry (8.66%), profitability coverage of EaDS (8.38%), the total profit of EaDS in the new energy vehicle industry (7.45%), the average growth rate of the output value of industrial high-tech enterprises (6.18%), and the growth rate of the value added of the new energy vehicle industry (6.14%).There are no existing studies on the impact of third-level indicators on chain resilience, but this study argues the following: The industrial value added and the industrial value-added growth rate are key indicators of regional economic activity and production efficiency.A chain with high value added and a high growth rate can provide a stronger economic base and financial support for its growth, which helps to maintain stability in the face of shocks and provides funds for recovery and reconstruction [69].
The profitability of regulated enterprises indicates that the enterprises in the industrial chain have strong market competitiveness and a good synergistic effect between the upstream and downstream of the industrial chain.This attracts upstream and downstream enterprises and service providers through strong market demand, forming industrial clusters and enhancing the agglomeration effect and synergistic effect of the industrial chain.
The high profits of the top enterprises can serve as a wind vane for the development of the entire industry chain, leading other enterprises to carry out technological innovation and market expansion.This can also disperse the risks of the entire industry chain by virtue of the scale and market influence of the top enterprises, increasing the resilience of the industry chain.
In addition to contributing to the extensive literature on the comprehensive indicator evaluation system, we extend the analysis of the behavior of the new energy vehicle industry chain and the enterprises within it.Researchers from the Jiangsu Institute of Strategic Studies and personnel from the Vehicle Industry Section of Changzhou Industry and Information Bureau affirmed the scientific validity and effectiveness of the index system, confirming that it can indeed quantify the resilience of the new energy vehicle industry chain.
Another important contribution this study makes to the existing research is the evaluation of the resilience of the new energy vehicle industry chain in Changzhou.Since implementing a closed-loop development approach-encompassing "development, storage, delivery and use"-Changzhou has been vigorously developing a new energy economy, with new energy vehicles being the main focus of the "use" sector [90,91].The 2019-2022 new energy vehicle industry chain resilience composite score is consistent with the trend in new energy vehicle production changes.According to the data released by Changzhou City Statistics Breau, the results of this study on the resilience of Changzhou's new energy vehicle industry chain align with the development of the industry in the city [90][91][92].
In 2019, new energy vehicles were included in the seven high-tech industries of Changzhou City.In January 2021, the Changzhou City Bureau of Statistics began including the new energy vehicle industry in the scope of government-published economic operation information [93].By August 2021, the contribution rate of the new energy vehicle industry to the growth of the total value of the industrial output above the scale was being published [94], and by November 2022, the new energy vehicle industry had become the leading new energy industry category in terms of the contribution rate [91,95].The annual measurement results of the resilience of the new energy vehicle industry chain are basically consistent with the development of the industry in Changzhou.
Secondly, to further increase the resilience of the new energy vehicle industry chain, Changzhou City has drafted and enacted a series of measures to develop the new energy vehicle industry since 2023.These include the Changzhou New Energy Industry Promotion Regulations (Draft) [96], the Changzhou New Energy Industry Development Plan [97], Changzhou Science and Technology Innovation Promotion Regulations [95], and the Changzhou Accelerating the Construction of New Energy Vehicle Parts and Components Industry Ecological Work Program [4].These measures propose developing the new energy vehicle industry, including the compilation and implementation of industry-specified plans for new energy vehicles and automotive core components [92].
The measures also advocate for new projects to prioritize the development of the new energy vehicle industry chain.Specifically, they stipulate that, in principle, all new and replacement official vehicles for government agencies and institutions should be new energy vehicles.This policy aims to expand the sales market through government procurement.Furthermore, they aim to coordinate the overall development of the new energy industry chain, promote leading enterprises to collaborate with advantageous parts and components supply chain enterprises, and foster collaboration among the industry chain and upstream and downstream supply chain enterprises.The measures also support the steady expansion of the new energy vehicle industry, continuous improvement of intelligent vehicle production capacity, and active building of the new energy vehicle industry.
Production capacity, actively building well-known new energy vehicle brands and ecologically dominant enterprises, and promoting the construction of new energy vehicle industry highland aim to guide continuous technological innovation in the new energy vehicle industry.This innovation seeks to make enterprises in the industry bigger and stronger, thereby increasing the industry value added, expanding industry coverage, and improving the resilience of the new energy vehicle industry supply chain.
In January 2024, the Jiangsu Provincial People's Government issued the "Opinions on Supporting the High-Quality Development of Changzhou's New Energy Industry" to support Changzhou's high-quality promotion of new energy vehicle industry chain innovation and upgrading development [4].This initiative aims to reduce the weak links in the resilience of the supply chain of the new energy vehicle industry in Changzhou.
Thirdly, there is a certain time interval from investment to production in the new energy vehicle industry.For example, the Li Auto Changzhou production base was established in 2015 and put into production in 2019, and the BYD Changzhou production base was established in 2019 and put into production in 2022 [16,17].The current resilience indicator of the lower science and technology innovation output score indicates that the innovation inputs before and during 2022 have not yet formed outputs.However, the data from January to November 2023 show a leap forward in the original value indicator.
In the context of public health events represented by COVID-19 and the development of global economic regionalization, society pays more attention to the regional industrial chain and the development of its resilience, all of which contribute to the research and development of the regional industrial chain spurt.From a broad perspective, the resilience of the new energy vehicle industry chain is affected by resistance, adaptive resilience, renewal, and re-orientations.From a deeper perspective, in terms of new energy vehicle industry chain development, resistance is the first step to increase industry chain resilience, followed by adaptive resilience and renewal.Ultimately, the industry chain achieves leading competitiveness.The stronger the resilience of the regional industry chain of new energy vehicles, the more conducive it is to the high-quality development of the regional economy.Therefore, under the premise of not violating national policies and regulations, countries around the world should actively improve the resilience of the industry chain in segmented industrial manufacturing.

Conclusions
This article focuses on the fundamental concept of resilience, integrating the complexity in the new energy vehicle industry chain to develop a comprehensive evaluation index system for the resilience of the supply chain in Changzhou.By utilizing relevant data from enterprises within Changzhou's new energy vehicle supply chain, this study quantifies the resilience of this supply chain.This comprehensive approach ensures a robust analysis of supply chain resilience within the context of the new energy vehicle industry in Changzhou.
The comprehensive evaluation index system of new energy vehicle industry chain resilience includes four first-level indicators, 10 second-level indicators, and 29 third-level indicators, encompassing resistance, adaptive resilience, renewal, and re-orientations.Using data related to the Changzhou new energy vehicle industry chain for evaluation, the results show that the resilience of the Changzhou new energy vehicle industry supply chain is being strengthened, but it still falls short of ideal resilience.It is necessary to combine its own development advantages, gather innovative kinetic energy, and use the new energy vehicle and power battery industry as important leverage points.Efforts should be made to address the weak links in the industry cluster and accelerate the construction of an independent and controllable industry system in order to build a domestic innovation highland in the field of new energy vehicles.
Meanwhile, regarding the importance of resistance, studies using the entropy power method to calculate the weight of the new energy automobile industry chain's toughness show that adaptive resilience, renewal and re-orientation, resistance, and adaptive resilience are the basis of industry chain resilience [72,85].However, re-orientation has a higher weight than renewal.The reasons may lie in the following: under the strong support of the Changzhou Municipal Government, the layout of the Changzhou new energy automobile industry chain is relatively complete, and the proportion of enterprises in the industry chain will be more than 40% in 2022.However, constrained by the influence of Changzhou's city capacity, it is not attractive enough to high-level talents and advanced technological resources, which are crucial for the establishment and development of enterprise R&D and innovation centers.
The novelty of this paper lies in its construction of a comprehensive index system to evaluate the resilience of the new energy vehicle industry chain.It evaluates and describes industry chain resilience from the four dimensions of resistance, adaptive resilience, renewal, and re-orientations in order of progression, making the scientific issue of new energy vehicle industry chain resilience more concrete and visible.Additionally, this paper measures new energy vehicle industry chain resilience in Changzhou City, Jiangsu Province, contributing to regional industry chain resilience research.This measurement is particularly helpful for understanding the supply chain resilience of the new energy vehicle industry chain in Changzhou.
In addition to the above conclusions, there are certain research deficiencies in this study.In the future, we can consider expanding and deepening the following aspects of this study.First, we can expand the research area to include all of Jiangsu Province and even all of China.Second, we can identify the resilience evaluation intervals of the new energy vehicle industry chain, categorize them into strong resilience, general resilience, and weak resilience, and thus put forward targeted industrial development proposals.

Figure 1 .Figure 1 .
Figure 1.Changzhou s share of new energy vehicle production in Jiangsu Province and China (%).Notes: a1 represents the proportion of Changzhou s new energy vehicle production in Jiangsu

Figure 2 .
Figure 2. Comparison of the weights and scores of the first-level indicators of the resilience of the new energy vehicle industry chain.

Figure 3 .
Figure 3.Comparison of the weights and scores of the second-level indicators of the resilience of the new energy vehicle industry chain.

Figure 2 .
Figure 2. Comparison of the weights and scores of the first-level indicators of the resilience of the new energy vehicle industry chain.

Figure 2 .
Figure 2. Comparison of the weights and scores of the first-level indicators of the resilience of the new energy vehicle industry chain.

Figure 3 .
Figure 3.Comparison of the weights and scores of the second-level indicators of the resilience of the new energy vehicle industry chain.

Figure 3 .
Figure 3.Comparison of the weights and scores of the second-level indicators of the resilience of the new energy vehicle industry chain.

Figure 4 .
Figure 4. Comparison of the weights and scores of the third-level indicators of the resilience of the new energy vehicle industry chain.

Figure 4 .
Figure 4. Comparison of the weights and scores of the third-level indicators of the resilience of the new energy vehicle industry chain.
Note: * Enterprises are Changzhou enterprises or production layouts in Changzhou.

Table 2 .
Comprehensive evaluation index system of new energy vehicle industry chain resilience.
Note: Enterprises above Designated Size (EaDS) refers to industrial enterprises with a main business income of RMB 20 million and above.

Table 3 .
Changzhou new energy vehicle industry chain resilience index weights.

Table 4 .
Resilience score of the Changzhou new energy vehicle industry chain (2020-2022).

Table 4 .
Resilience score of the Changzhou new energy vehicle industry chain (2020-2022).

Table 4 .
Resilience score of the Changzhou new energy vehicle industry chain (2020-2022).