Research on Tacit Knowledge Dissemination of Automobile Consumers’ Low-Carbon Purchase Intention

Abstract

At present, domestic consumers hold a wait-and-see attitude toward new energy vehicles. Although sales are increasing year-by-year, there is still a big gap compared with traditional fuel cars. In view of this problem, this paper starts to consider the problem from the subjective internal cause. Based on the classic SIR model, the conversion rate of low-carbon purchase inclination of consumers of new energy vehicles is introduced to build a tacit knowledge dissemination model of the interaction of low-carbon and conservative purchase inclination. The system ensures that low-carbon purchase inclination is a positively advocated consumption value, and provides decision-making reference for the government’s publicity and enterprises’ technological innovation measures. For the first time, differential dynamics are combined with the purchase inclination of consumers of new energy vehicles. This article collected 1098 questionnaires, and the statistical results show that the most effective way for people to accept new energy vehicles is word of mouth from relatives and friends. This illustrates the necessity of studying tacit knowledge dissemination among consumer groups of new energy vehicles. The questionnaire also indicates what aspects of the performance of new energy vehicles consumers are concerned about, providing empirical evidence for the realization of consumption behavior. The improved SIR model dynamically depicts the evolution process of consumers’ purchasing inclination of new energy vehicles based on differential dynamics. The stable equilibrium point of the system was solved, and the main factors affecting the tacit knowledge transmission of purchase inclination included initial market parameters, conversion rate, and low-carbon and conservative transmission rates, etc. The practicality and effectiveness of the model was verified by numerical simulation. It can provide the government and enterprises with theoretical support and development suggestions in promoting the consumption and development of new energy vehicles.

1. Introduction

As a non-renewable resource, oil is a non-renewable resource, and China has a high degree of dependence on oil. The rise of new energy vehicles can alleviate China’s large demand for oil to a certain extent. The large amount of automobile exhaust fumes is an important source of environmental pollution. Energy conservation and emission reduction is therefore also a protection of the environment. Developed countries are developing new energy vehicles, and China should not lag behind. China should take advantage of the development trend of new energy to overtake other countries, in order to become a powerful automobile country. With the rapid development of the new energy vehicle industry, China has become the largest new energy vehicle production and marketing country in the world. In November 2020, the general office of the State Council issued the development plan for the new energy vehicle industry (2021–2035), which requires the in-depth implementation of the national strategy for the development of new energy vehicles, promote the high-quality and sustainable development of China’s new energy vehicle industry, and accelerate the construction of an automobile power.

From the point of view of energy security and environmental protection, growth of the new energy vehicle sector is a complex system evolution process; it is composed of interrelated subsystems. Therefore, the development of new energy vehicles not only requires the renewal of ideas and innovation of technology, but also requires the coordinated development of many social factors, such as market mechanisms, infrastructure, consumption habits, policies, culture, and so on [1]. Since 2015, China’s production and sales of new energy vehicles have ranked first in the world for three consecutive years. In 2017, the sales volume of new energy vehicles has reached 770,000, and the holding volume has exceeded 1.6 million, accounting for 50% of the total global holding volume of new energy vehicles [2]. By 2020, China’s annual sales of new energy vehicles reached 1.37 million, and the market penetration rate increased to 5.4%. The driving range of mainstream new energy vehicles has reached 500–600 km, close to the level of gasoline vehicles [3]. Domestic scholars have evaluated the sustainable development level of the new energy automobile industry from the perspectives of the technological innovation environment, industrial development foundation, social support conditions, ecological environment, economic development and social culture, and innovation ecology [4]. Other scholars evaluated the competition situation of the global new energy automobile industry from the perspectives of market size, industrial chain integrity, public infrastructure guarantee, market development degree, technological innovation and brand recognition, and policy effectiveness [5]. Although people have studied the development of new energy vehicles from various angles, the factor that can directly affect purchase intensity is ignored, that is, consumers’ low-carbon purchase intention. Low-carbon purchase intention emphasizes mobilizing people’s subjective initiative and improving their environmental awareness. Consumers’ subjective recognition and acceptance of low-carbon travel can enable new energy vehicles to occupy an advantaged position in the competition with fuel vehicles. Of course, it is inevitable to improve the performance of new energy vehicles, because they can enhance people’s recognition of them. To this end, this article carried out a relevant questionnaire and collected data for statistics, to provide a basis for enterprises to tackle technical problems and for government policy guidance.

The development of new energy vehicles in China mainly depends on policy. The country has been promoting the development of new energy vehicles more actively and systematically. Although some achievements have been made, the sustainable and stable development of new energy vehicles cannot completely rely on government support. Researchers should consider whether consumers truly recognize and accept new energy vehicles, and they should increase people’s green and low-carbon purchase inclination, which is the fundamental way to ensure the circular development of new energy vehicles. After publicity and education in recent years, more and more people have realized the importance of low-carbon environmental protection and are making their own contributions to the ecological environment with their own actions. If people want to have a green earth, it is vital to raise people’s awareness of low-carbon environmental protection.

From the perspective of consumers, this paper considers the impact of green and low-carbon environmental awareness on the sales of new energy vehicles. Low-carbon buying consciousness is a kind of tacit knowledge, which was put forward by Michael Polanyi in Philosophy in 1958. “There are two kinds of human knowledge,” he argued. “What is usually described as knowledge” expressed in written words, charts and mathematical formulas, is only one type of knowledge. And unexpressed knowledge, like the knowledge that people have when they are doing something, is a different kind of knowledge. He called the former explicit knowledge and the latter tacit knowledge. Scholars have made great achievements in the study of tacit knowledge. Consumers are a group, and the classic model to study the trend of the crowd is the Susceptible Infected Recovered Model (SIR). At first, the model divided infectious patients into three groups: uninfected, infected, and cured, and studied the rule of the number change of these three groups. This is close to the change of consumer groups to be studied in this paper, so it is selected as the basic research model. This paper improves the model according to the characteristics of the consumer group’s structure. Considering the internal factors, such as the holding rate of low-carbon purchase intention in the population, as well as the degree of mutual influence of various groups, the change rule of the number of consumers’ low-carbon purchase intention is studied. This study analyzes the dissemination and development process of tacit knowledge of green and low-carbon purchase inclination among consumers, based on the improved SIR model, and explores how to effectively disseminate green and low-carbon purchase inclination, in order to take effective measures to increase the sales of new energy vehicles. It has important guiding significance for relevant departments to address green and low-carbon purchase inclination and promote the high-quality development of the new energy vehicle industry.

2. Literature Review

2.1. Research on the Development of New Energy Vehicles

China’s National Bureau of Statistics (NBSC) reported that the number of cars was 260 million in 2019, an increase of 8.83%, which causes serious air pollution and is not conducive to the green and sustainable development of the environment. Although the government has issued some corresponding measures, such as restricting car travel, most of the measures have not significantly improved air pollution [6]. New energy vehicles are powered by energy storage batteries, which can greatly reduce carbon emissions. Therefore, they have been adopted and promoted by governments around the world in recent years to improve global warming and environmental pollution [7]. The Chinese government has introduced a series of incentive policies, which have led to the exponential growth of the new energy vehicle industry, which has become the world’s largest market [8]. By November 2021, sales of new energy vehicles in China exceeded 7 million units, ranking first in the world, and the market share of newly registered vehicles reached 10 percent. The Chinese government plans to increase the market share of new energy vehicles to 20 percent by the end of 2025. It is expected to maintain a rapid growth trend in the future [9]. New energy vehicles are still in their infancy in China, and inevitably there are some hidden dangers, such as a heavy financial expenditure burden and insufficient charging infrastructure, and core technology has not yet broken through, and so on [10]. Some scholars also believe that carbon emission constraint is an important factor affecting the development of new energy vehicles [11]. These constraints are the result of considering the problem from an objective perspective. In fact, the change of people’s subjective consciousness and the enhancement of low-carbon purchase inclination can fundamentally promote the development of new energy vehicles. The improvement of objective factors assists consumers to establish and enhance low-carbon purchase inclination. Therefore, the two should be carried out at the same time to achieve the ideal effect.

2.2. Research on the Tacit Knowledge Dissemination Model

Nonaka proposed the classic SECI knowledge creation model, pointing out that explicit knowledge and tacit knowledge can be transformed and transmitted through socialization, externalization, integration, and internalization [12]. The classical SECI model shows some limitations and does not study the transmission process of tacit knowledge in the unrevealed tacit state. The infectious disease model is a typical model to solve tacit knowledge dissemination. The SIR (Susceptible Infective Removal) model, jointly developed by Kermask and McKendrick, is the most classic and basic model of the infectious disease model, which makes a fundamental contribution to the dynamics of knowledge transmission in the tacit state. Many scholars apply the SIR model to the field of knowledge dissemination [13]. Bai studied SIR model with time delay [14]. C.N. Agnstmann et al. proposed a fractional SIR model related to age structure [15]. Zhao studied the stochastic SIR model and analyzed the threshold of its diffusion with the non-negative semi-saddle convergence theorem [16]. Li Jingjing used the improved SIR model to analyze the learning network and established the SIRL model by introducing the role of the leader factor, which enriched the knowledge transmission dynamics theory of the complex network [17]. Cowan proposed a knowledge diffusion model and a knowledge growth model on complex networks [18], studied the relationship between network structure and knowledge diffusion, network structure and knowledge growth, and better simulated the dynamic characteristics of knowledge diffusion in economic networks. The reality of complex network simulation is also verified in rumors, information diffusion [19], and the spread of infectious diseases [20]. Moronc and Taylor put forward a general model of knowledge diffusion rules based on the face-to-face network, and put forward some dominant mechanisms of knowledge diffusion called “social learning” [21]. Wang proposed an improved SIRaRu model based on the Sir Model to study the propagation characteristics of information in isomorphic networks and heterogeneous networks [22]. In order to compare the merits and demerits of different forgetting functions, Ncmbhard and Osothsilp used survey data to estimate and verify model parameters [23]. Zhao is one of the few scholars who noticed the defects of numerical simulation. He considered the role of the forgetting mechanism in the rumor propagation model, derived the mean field equation, and carried out some empirical work [24]. Enatsu Y et al. proposed that the stimulation of exogenous variables could easily lead to the re-transformation of some immune nodes into susceptible nodes, and established an SIRS propagation model [25].

2.3. Research on Consumers’ Low-Carbon Inclination

In recent years, environmental protection has become the most concerning issue. People’s low-carbon awareness is the subjective motivitation for the improvement of environmental greenness. Many scholars have studied consumers’ low-carbon purchase inclination [26]. Some consumers tend to pay higher prices to purchase low-carbon products [27]. Businesses have noticed the change in the consumption concept of consumers’, and they have begun to pay attention to the use of low-carbon labels. Some household appliances and other electrical products are labeled with energy saving labels [28]. There are two kinds of government subsidies: subsidies for manufacturers which produce green products and subsidies for consumers who buy green products. A supply chain includes two kinds of power structures: the manufacturing leader and the retail leader [29]. Xu et al. constructed the differential pricing model of green products and non-green products with government subsidies from the perspective of reducing the cost of green products, and obtained the optimal pricing strategy [30]. In regard to carbon-concerned demand, Du et al. studied how low-carbon supply policies affect supply chain performance [31]. Yu et al. analyzed the green policy effect of optimal production with consumer environmental awareness [32]. Based on the analysis of the pricing and emission reduction optimization strategy, a contract mechanism for supply chain coordination and optimization was designed by using the Robinson bar buying model [33]. Meng et al. considered two competitive firms, one of which adopted low-carbon technology and the other did not, and studied the product selection problem with carbon tax [34]. Song and Gao designed a revenue-sharing contract in order to improve the greening level of the products of a supply chain [35]. Su et al. concluded that when the government subsidizes consumers, the carbon emission level and retail price are directly proportional to the subsidy coefficient under the two power structures [36]. The safety, maximum speed, battery capacity, comfort, and price of new energy vehicles have a significant impact on purchase inclination [37]. The capacity of the power battery directly affects the range of the car, which is also one of the most concerning factors for consumers [38]. The Chinese government has adopted some policies conducive to the development of the new energy vehicle industry, such as tax exemptions and direct subsidies, which have played a positive role in promoting consumers’ low-carbon purchase inclination [39].

2.4. Study on the Process of Knowledge Transmission in Groups

The spread of tacit knowledge among groups is influenced by personal experience, preference, and interest. Nonaka and Konno et al. believe that customer tacit knowledge is reflected in customers’ evaluation, feedback, thoughts, feelings, and expectations related to products and services, as well as perceived customer habits, preferences, and interests [40]. From the network perspective, Haas et al. believe that knowledge sharing is constructed based on the binary network relationship of “provider–seeker” and is a process in which knowledge providers share knowledge with emotionally connected seekers [41]. From the perspective of interaction, the essence of knowledge sharing is the communication and interaction between subjects, and it is a behavioral process [42]. From the perspective of exchange, knowledge sharing is an activity of exchanging knowledge between at least two subjects [43,44]. It is a process in which individuals exchange explicit and implicit knowledge and jointly create new knowledge [45]. As far as learning is concerned, knowledge sharing is the process of learning between subjects and forms a learning atmosphere between them. The sharing subject transfers its expertise (experience and skills) to the other subject and makes it master as much as possible [46].

From the above literature review, it is not difficult to see that there are few relevant studies combining consumers’ low-carbon purchase inclination with the tacit knowledge dissemination SIR model. Most of the above researchers add some influential factors to the SIR model, or change the forgetting mechanism, to study the restrictive factors of the quantitative change of a certain group of people in the model. Few researchers divide the three basic groups in the model and study their mutual influence and changing behavior. Considering the influence of low-carbon purchase inclination among consumers of new energy vehicles, this paper divides communicators into two categories: purchasing new energy vehicles and purchasing fuel vehicles. This paper studies how to enhance consumers’ low-carbon purchase inclination and strengthen the purchasing power of new energy vehicles, so as to enhance the green environment and obtain the stable growth of the new energy vehicle industry.

3. Basic Assumptions and Model Construction

3.1. Differential Dynamical System

The improved SIR model reflects the rule of quantity change of consumer groups. Differential dynamical systems are mainly studied in terms of the global properties of dynamical systems evolving with time and their changes in perturbations. If you want to analyze the specific influencing factors of this law and investigate the relationship between the evolution curve and each factor, you need to combine the differential dynamical system for analysis and research. This is also the reason why the differential dynamical system is used to analyze the low-carbon purchase intention of consumers of new energy vehicles.

This paper, for the first time, combines the differential dynamical system with the purchase intention of consumers of new energy vehicles, so it is necessary to introduce the important method of differential dynamics. The differential dynamical system is a branch of the dynamical system. The research object of the dynamical system is the state space R composed of all possible states of the system and the evolution law composed of transformations in R, as shown in Formula (1).

$${\phi }_t:R\to R(-\infty <t<+\infty )$$

(1)

This means that a certain state x ∈ R of the system evolves into state φ_t(x) at time t in accordance with this law. Generally, the evolution law should meet the following three conditions:

1. ${\varphi }_0(x)=x$

2. ${\varphi }_s({\varphi }_t(x))={\varphi }_{s+t}(x)$

3. φ_t(x) is a continuous function of t and x.

In order to satisfy the continuity of initial value x in the condition, the state space R should have a topological structure. Such a system is called a dynamical system.

If R is an N-dimensional Euclidean space En, or more generally, an open subset G of it, and φ_t(x) is a constant differentiable to t: d_φt(x)/d_t = s(φ₁(x)), then the dynamical system is said to be produced by ordinary differential equations d_x/d_t = s(x) or a constant microsystem S. The main characteristic of the differential dynamical system is the whole disturbance problem, especially in the structural stability.

Suppose there is a constant microsystem S of C¹ on Mn. If the perturbation of C¹ does not change the topological structure of the phase diagram, that is, if S has a neighborhood γ in X(Mⁿ), then S is considered structurally stable, as long as X ∈ γ has the topological transformation Mⁿ→Mⁿ mapping the orbital of S to the orbital of X.

The densification theorem proved by Pesciotto states that there are dense subsets of X(M²) composed of structurally stable systems. The characteristic theorem he proved shows that systems in X(M²) are structurally stable if and only if their non-stray set consists of only a finite number of hyperbolic singularities and hyperbolic periodic orbits, and there is no saddle point connection, that is, orbits without hyper-constant points approach saddle points in both positive and negative directions.

The actual problem studied in this paper is how consumers’ purchasing inclination changes from traditional fuel vehicles to new energy vehicles. There are many factors influencing people’s purchasing inclination, such as brand, price, trust, and so on. These indicators are often subjective and reflect the situation over time. Time changes often need to be re-investigated to obtain the latest data that reflect the impact of the current indicators. The change of one index makes the whole system change significantly, so the solution to dynamic problems is very complicated. This paper studies the transition process from negative to positive purchase inclination of new energy vehicles, for which the deterministic differential dynamical system is most suitable to solve the tacit knowledge transmission problem.

Based on the differential dynamical system, this paper selects the flow quantity of consumers with purchase demand as the main variable. New energy vehicles are a new thing in recent years; people have expectations and hold a skeptical attitude at the same time. People always hope that they can live a comfortable and happy life, but at present, the advantages and shortcomings of new energy vehicles still need to be verified. Therefore, car buyers can be roughly divided into two groups: those with low-carbon purchase inclinations and those with conservative purchase inclinations. The crowd is a mobile collective, in the process of mutual communication, and when the purchase inclination changes, there a tacit knowledge dissemination process takes place. This is a process of continuous reciprocating movement. In the end, people influence each other and feel that the advantages of new energy vehicles are higher than the disadvantages, and the crowd flow tends to be more environmentally friendly and low-carbon, and eventually achieves a stable pattern.

3.2. Basic Assumptions

At present, compared with fuel vehicles, new energy vehicles have many advantages, such as low-carbon, environmental protection, acceleration, and stability, but they also have their disadvantages, such as short mileage, low temperature effects on the power battery, battery service life, frequent charging, and changing cycles, etc. Consumers comprehensively consider these factors when purchasing new energy vehicles. To strengthen the purchasing power of new energy vehicles, consumers’ low-carbon purchase inclination needs to be strengthened and stably spread among consumer groups, to ensure the sustainable and effective development of new energy vehicles. The low-carbon purchase inclination studied in this paper is regarded as a single tacit knowledge, which is spread among automobile consumers, and the SIR model is improved. The assumptions of this paper are as follows: It is assumed that the number of people with the ability to buy cars is N and is fixed, that is, the change and extinction of the consumption ability of these kind of people are not considered. They are divided into four categories: The first category is the people who have the need to buy cars, but are not sure whether to buy traditional fuel vehicles or new energy vehicles, who are called “demanders”, and their proportion in the total number is A(t). These people do not have a low-carbon purchasing behavior of new energy vehicles, so they do not have the ability to spread tacit knowledge of low-carbon purchase inclination. The second group refers to those who have purchased new energy vehicles and have the ability to spread it to other demanders through their own purchase behavior and low-carbon purchase inclination, who are called “low-carbon communicators”, and their proportion in the total number is I(t). The third group maintains a wait-and-see attitude in favor of traditional fuel vehicles and doubts new energy vehicles. People with this inherent way of thinking also kave a certain communication ability and they are called “wait-and-see communicators”, and their proportion in the total number is G(t). The fourth category is that of consumers who no longer need to use vehicles; they give up using existing vehicles and no longer buy them. They are called “deserters”, and their proportion in the total number is R(t). Then the proportional relationship as shown in Formula (2).

$$A(t)N+I\left(t\right)N+G\left(t\right)N+R\left(t\right)N=N$$

(2)

Based on this, it is assumed that among the people with the ability to buy cars, the proportion of people who need to use cars is δ. These people are called demanders because they have not purchased any type of vehicle and do not have the ability to spread tacit knowledge to surrounding people.

People with communication ability can be divided into two categories. One is the people who buy new energy vehicles. They have strong low-carbon purchase inclination, which affects the surrounding people to gradually accept and buy new energy vehicles. These people are regarded as “low-carbon purchase inclination communicators”. The other is people who buy fuel vehicles. They are skeptical about some disadvantages of new energy vehicles, which drives the surrounding people to buy fuel vehicles or keep a wait-and-see state. They are regarded as “transmitters of conservative purchase inclination”.

It is assumed that the contact between the two types of communicators and the demanders must have a certain infectivity, and the total effect rate of car purchase is assumed to be α. When the consumers who have not bought a vehicle come into contact with the consumers who have bought a vehicle, they become the buyers with the infection rate α. It is assumed that the low-carbon purchase inclination group that buys new energy vehicles infects the demanders at the α₁ transmission rate, and the fuel vehicle group affects the demanders at the α₂ transmission rate.

The implementation of national policy support and financial subsidies and other measures, as well as the publicity of low-carbon environmental awareness, have a positive role in promoting the production and sales of new energy vehicles and a positive guiding role for automobile consumer groups. These policies play an important and positive role in the transmission of low-carbon purchase inclination. Therefore, low-carbon transmission for the wait-and-see state has bought traditional fuel car groups, who have a certain impact transformation effect. It is assumed that the communicator of conservative purchase inclination abandons the fuel car and becomes a low-carbon communicator with the conversion rate φ. Consumers who have bought new energy vehicles themselves have a high willingness to buy low-carbon vehicles, and the possibility of this group turning into wait-and-see is quite small, so this paper does not consider them.

When consumers no longer need to use vehicles due to lifestyle or other reasons, the low-carbon communicators are transformed into quitters with θ₁ probability, and the conservative communicators are transformed into quitters with θ₂ probability.

If low-carbon purchase inclination spreads actively and effectively in the whole social group, a universal code of conduct is formed, which is then difficult to be forgotten by the group. Therefore, this paper does not consider the forgetting of low-carbon purchase inclination.

3.3. Model Specification

Based on the above assumptions, the tacit knowledge dissemination model of low-carbon purchasing inclination of consumers of new energy vehicles is shown as Figure 1.

The mathematical model can be expressed as Formula (3).

$$\{\begin{array}{l}N\frac{d_{A(t)}}{d_t}=\delta N-{\alpha }_{1}A(t)N-{\alpha }_{2}A(t)N\\ N\frac{d_{I(t)}}{d_t}={\alpha }_{1}A(t)N+\phi G(t)N-{\theta }_{1}I(t)N\\ N\frac{d_{G(t)}}{d_t}={\alpha }_{2}A(t)N-\phi G(t)N-{\theta }_{2}G(t)N\\ N\frac{d_{R(t)}}{d_t}={\theta }_{1}I(t)N+{\theta }_{2}G(t)N\\ A(t)N+I(t)N+G(t)N+R(t)N=N\\ A_0=A(0),G_0=G(0),I_0=I(0),R_0=R(0)\end{array}$$

(3)

Divide both sides of Formula (3) by constant n at the same time to obtain the differential dynamical model of tacit knowledge transmission in power battery reverse supply chain, as shown in Formula (4).

$$\{\begin{array}{l}\frac{d_{A(t)}}{d_t}=\delta -{\alpha }_{1}A(t)-{\alpha }_{2}A(t)\\ \frac{d_{I(t)}}{d_t}={\alpha }_{1}A(t)+\phi G(t)-{\theta }_{1}I(t)\\ \frac{d_{G(t)}}{d_t}={\alpha }_{2}A(t)-\phi G(t)-{\theta }_{2}G(t)\\ \frac{d_{R(t)}}{d_t}={\theta }_{1}I(t)+{\theta }_{2}G(t)\\ A(t)+I(t)+G(t)+R(t)=1\\ A_0=A(0),G_0=G(0),I_0=I(0),R_0=R(0)\end{array}$$

(4)

This is the initial value problem of the Bernouli equation. The analytical solutions of the above differential equations can be obtained as shown in Formulas (5)–(8).

$$A(t)=\frac{\delta }{{\alpha }_1+{\alpha }_2}+c{e}^{-({\alpha }_1+{\alpha }_2)t}$$

(5)

The formula shows that people with purchasing power and demand for cars do not have some tacit knowledge temporarily when they are not exposed to low-carbon purchase inclination communicators and conservative purchase inclination communicators, and the changing trends of these people is clear over time.

$$\begin{array}{ll}I(t)& =\frac{({\alpha }_1+{\alpha }_2)\delta \phi +{\alpha }_1\delta {\theta }_2}{(\phi +{\theta }_2)({\alpha }_1+{\alpha }_2){\theta }_1}+c{e}^{-{\theta }_{1}t}\\ & +\frac{c{\alpha }_1(\phi +{\theta }_2-{\alpha }_1-{\alpha }_2)+c\phi {\alpha }_2}{(\phi +{\theta }_2-{\alpha }_1-{\alpha }_2)({\theta }_1-{\alpha }_1-{\alpha }_2)}{e}^{-({\alpha }_1+{\alpha }_2)t}\\ & +\frac{c\phi }{{\theta }_1-\phi -{\theta }_2}{e}^{-(\phi +{\theta }_2)t}\end{array}$$

(6)

This formula indicates that consumers who have purchased new energy vehicles have low-carbon purchase inclination and may spread this awareness to demanders through some contact, affecting their purchase inclination, and the proportion of low-carbon purchase inclination disseminators changes over time in the total number of people.

$$G(t)=c{e}^{-(\phi +{\theta }_2)t}+\frac{c{\alpha }_2}{\phi +{\theta }_2-{\alpha }_1-{\alpha }_2}{e}^{-({\alpha }_1+{\alpha }_2)t}+\frac{{\alpha }_2\delta }{(\phi +{\theta }_2)({\alpha }_1+{\alpha }_2)}$$

(7)

This formula indicates that consumers who have purchased traditional fuel cars have conservative purchase inclination and may spread this consciousness to demanders through some ways, affecting their purchase inclination, and the proportion of conservative purchase inclination communicators changes over time in the total number of people.

$$\begin{array}{l}R(t)=\frac{(({\alpha }_1+{\alpha }_2)\delta \phi +{\alpha }_1\delta {\theta }_2+{\alpha }_2\delta {\theta }_2)t}{(\phi +{\theta }_2)({\alpha }_1+{\alpha }_2)}-\frac{c{\theta }_2{e}^{-(\phi +{\theta }_2)t}}{\phi +{\theta }_2}-\frac{c{\alpha }_2{\theta }_2{e}^{-({\alpha }_1+{\alpha }_2)t}}{(\phi +{\theta }_2-{\alpha }_1-{\alpha }_2)({\alpha }_1+{\alpha }_2)}\\ -c{\theta }_1{}^2{e}^{-{\theta }_{1}t}-\frac{(c{\alpha }_1{\theta }_1(\phi +{\theta }_2-{\alpha }_1-{\alpha }_2)+c\phi {\alpha }_2{\theta }_1)e^{-({\alpha }_1+{\alpha }_2)t}}{(\phi +{\theta }_2-{\alpha }_1-{\alpha }_2)({\theta }_1-{\alpha }_1-{\alpha }_2)({\alpha }_1+{\alpha }_2)}-\frac{c\phi {\theta }_1{e}^{-(\phi +{\theta }_2)t}}{({\theta }_1-\phi -{\theta }_2)(\phi +{\theta }_2)}\end{array}$$

(8)

This formula represents the change rule of abandoned people over time. According to the hypothesis in this paper, the people who no longer use cars are all classified as quitters, so the proportion of quitters increases over time.

4. Analysis on the Stability of Tacit Knowledge Dissemination

4.1. Uniformly Stable Equilibrium Point

In this model, the change of immune R(t) was related to the population loss of I(t) and G(t), but the change of A(t), I(t), and G(t) was not related to R(t). Therefore, considering that the differential dynamical model is composed of the first three, without considering the changes of the immune, the system expression is shown as Formula (8).

$$\{\begin{array}{l}\delta -{\alpha }_{1}A(t)-{\alpha }_{2}A(t)=0\\ {\alpha }_{1}A(t)+\phi G(t)-{\theta }_{1}I(t)=0\\ {\alpha }_{2}A(t)-\phi G(t)-{\theta }_{2}G(t)=0\end{array}$$

(9)

When time t tends to infinity, the changes of the three types of personnel with time are expressed as Formulas (10)–(12).

$$\underset{t\to \infty }{\lim }A(t)=\frac{\delta }{{\alpha }_1+{\alpha }_2}$$

(10)

Formula (10) shows that on the premise that the number n of people with purchasing power is fixed, the proportion of demand people with learning ability eventually reaches a stable equilibrium point over time, that is the steady-state value $A(\infty )=\frac{\delta }{{\alpha }_1+{\alpha }_2}$. The value of the stable point is influenced by the proportion of purchasers joining δ, the propagation rate of low-carbon purchase inclination α₁, and the propagation rate of conservative purchase inclination α₂.

$$\underset{t\to \infty }{\lim }I(t)=\frac{({\alpha }_1+{\alpha }_2)\delta \phi +{\alpha }_1\delta {\theta }_2}{(\phi +{\theta }_2)({\alpha }_1+{\alpha }_2){\theta }_1}$$

(11)

Formula (11) indicates that on the premise that the number of people with purchasing ability N is fixed, the proportion of disseminators with tacit knowledge of low-carbon purchasing inclination eventually reaches a stable equilibrium point over time, namely the steady-state value $I(\infty )=\frac{({\alpha }_1+{\alpha }_2)\delta \phi +{\alpha }_1\delta {\theta }_2}{(\phi +{\theta }_2)({\alpha }_1+{\alpha }_2){\theta }_1}$. The value of the stable point is affected by the proportion of users δ, the transmission rate of low-carbon purchase inclination α1, the transmission rate of conservative purchase inclination α₂, the conversion rate of conservative purchase inclination communicator φ, the abandonment rate of low-carbon communicator θ₁, and the abandonment rate of conservative communicator θ₂.

$$\underset{t\to \infty }{\lim }G(t)=\frac{{\alpha }_2\delta }{(\phi +{\theta }_2)({\alpha }_1+{\alpha }_2)}$$

(12)

Formula (12) shows that on the premise that the number n of people with purchasing power is fixed, the proportion of abandoned people who give up the tacit knowledge for some reason eventually reaches a stable equilibrium point with time, that is the steady-state value $G(\infty )=\frac{{\alpha }_2\delta }{(\phi +{\theta }_2)({\alpha }_1+{\alpha }_2)}$. The value of the stable point is affected by the proportion of consumers joining δ, the transmission rate of low -carbon purchase inclination α₁, the transmission rate of conservative purchase inclination α₂, the conversion rate of conservative purchase inclination spreaders φ, and the abandonment rate of conservative spreaders θ₂.

4.2. Analysis of Parameter Controls of Tacit Knowledge Dissemination of Low-Carbon Purchase Inclination

Proposition 1.

The proportion of communicators of low-carbon purchase inclination I(∞) is a monotonously increasing function of the proportion of demanders joining δ.

It is proved that through the expression $\frac{\partial I(\infty )}{\partial \delta }=\frac{({\alpha }_1+{\alpha }_2)\phi +{\alpha }_1{\theta }_2}{(\phi +{\theta }_2)({\alpha }_1+{\alpha }_2){\theta }_1}>0$, I(∞) is the monotonically increasing function of the proportion of demander to δ. When other parameters are fixed, the proportion of communicators of low-carbon purchase inclination is related to the participation rate of demanders, and with the increase in the participation rate of demanders, the proportion of communicators of low-carbon purchase inclination increases, that is to say, the two are positively correlated.

The increase in the number of car buyers strengthens the possibility of car purchase, adds to the probability of consumers choosing to buy new energy vehicles, and increases the possibility of consumers turning into disseminators of low-carbon purchase inclination. When other factors are constant and each parameter meets $\delta >{\theta }_1+{\theta }_2+{\alpha }_2-{\alpha }_1-\phi$, the tacit knowledge of low-carbon purchase inclination can be guaranteed to spread. At the same time, it can resist the negative factors that prevent the transmission, including the transmission of conservative purchase inclination, the scrapping of an automobile when its life has ended, and the transmission and abandonment of low-carbon purchase inclination by consumers who do not need to use automobiles.

Proposition 2.

The proportion of low-carbon purchase inclination communicators I(∞) is a monotonically increasing function of the change rate φ of conservative purchase inclination communicators.

It is proved that through the expression $\frac{\partial I(\infty )}{\partial \phi }=\frac{\delta }{(\phi +{\theta }_2){\theta }_1}>0$, I(∞) is a monotonically increasing function of the transition rate φ of the conservative purchase inclination communicator. When other parameters are fixed, the proportion of low-carbon purchase inclination communicators is related to the conversion rate of conservative purchase inclination communicators, and with the increase in the conversion rate of conservative purchase inclination communicators, the proportion of low-carbon purchase inclination communicators increases, and the two are positively correlated.

Consumers who buy fuel cars are affected by factors such as poor acceleration, rising oil prices, and constant contact with consumers who buy new energy vehicles, coupled with the government’s low-carbon environmental awareness publicity and the implementation of a series of preferential policies for the purchase of new energy vehicles, etc. The promotion of the spread of low-carbon purchase inclination changes the attitude of buyers with conservative purchase inclination. Therefore, some of them hold a wait-and-see attitude. However, for the original conservative people with strong purchase inclination to accept new carbon emissions, they will give up existing fuel cars and choose to buy new energy cars again at a certain conversion rate. The expression $\phi >{\theta }_1+{\theta }_2-\delta$ can be used to describe when other factors are considered as constant, and when the conversion rate of the communicator of conservative purchase inclination is greater than the difference between the abandonment rate and the joining rate of the demander. At this point, the stable propagation of low-carbon purchase inclination can be guaranteed in the system. Here, the abandonment rate refers to the sum of the abandonment rate of the communicators of low-carbon purchase inclination and that of the communicators of conservative purchase inclination.

Proposition 3.

The proportion of low-carbon purchase inclination communicators I(∞) is a monotonicity-decreasing function of the abandonment rate θ₁.

It is proved that through the expression $\frac{\partial I(\infty )}{\partial {\theta }_1}=\frac{-(({\alpha }_1+{\alpha }_2)\delta \phi +{\alpha }_1\delta {\theta }_2)}{(\phi +{\theta }_2)({\alpha }_1+{\alpha }_2){\theta }_1{}^2}<0$, I(∞) is a monotone decreasing function of the abandonment rate θ₁ of communicators with low-carbon purchase inclination. When other parameters are fixed, the proportion of low-carbon purchase inclination communicators is related to the abandonment rate of low-carbon purchase inclination communicators, and with the increase in the abandonment rate of low-carbon purchase inclination communicators, the proportion of low-carbon purchase inclination communicators gradually decreases, that is to say, the two are negatively correlated.

When new energy vehicles reach their service life, buyers give up using new energy vehicles due to changes in their work or way of life, thus becoming abandoners of low-carbon purchase inclination. In order to ensure the proportion of communicators of low-carbon purchase inclination and ensure the stable development of the communication of low-carbon purchase inclination, the abandonment rate of low-carbon purchase inclination should be controlled within a certain range. If ${\theta }_1>{\alpha }_1+\phi$, the number of transmissions of low-carbon purchase inclination decreases with the increase in the proportion of abandoners at a certain point, which eventually leads to the failure of transmission of low-carbon purchase inclination. In order to avoid the occurrence of this situation, it is suggested that government departments increase the publicity of green and low-carbon purchase inclination, appropriately increase consumer subsidies for new energy vehicles, and encourage related enterprises, including new energy vehicle enterprises, power battery production, and recycling enterprises, to strengthen technological innovation. During the process of technological innovation, the enterprises should try their best to overcome the existing shortcomings of new energy vehicles, such as range and charging pile construction. By doing this, they can achieve the goal of making consumers prefer new energy vehicles when making choices, and low-carbon purchase inclination is promoted.

Proposition 4.

The proportion I(∞) of communicators with low-carbon purchase inclination is a monotonicity decreasing function of forgetting rate θ₂ of communicators with conservative purchase inclination.

It is proved that I(∞) is a monotonously decreasing function of forgetting rate θ₂ of communicators with conservative purchase inclination, through the expression $\frac{\partial I(\infty )}{\partial {\theta }_2}=\frac{-{\alpha }_2\delta \phi }{(\phi +{\theta }_2){({\alpha }_1+{\alpha }_2)}^2}<0$. When other parameters are fixed, the proportion of low-carbon purchase inclination communicators is related to the abandonment rate of conservative purchase inclination communicators, and with the increase in the abandonment rate of conservative purchase inclination communicators, the proportion of low-carbon purchase inclination communicators gradually decreases, that is to say, the two are negatively correlated.

Although the communication of low-carbon purchase inclination to buy new energy vehicles is not directly affected by the abandonment rate of conservative communicators, it is indirectly affected. This is because the increase in the abandonment rate of conservative purchase inclination communicators reduces the base for them to become low-carbon communicators, so that the proportion of low-carbon purchase inclination communicators decreases, which is not conducive to the dissemination of low-carbon purchase inclination. If ${\theta }_2>{\alpha }_1+{\alpha }_2-{\theta }_1$, the transmission of low-carbon purchase inclination is not able to proceed at some point. To strengthen the awareness of green and low-carbon environmental protection is conducive to global climate improvement. From the perspective of long-term sustainable development, countries and individuals should take active measures. Therefore, in the process of spreading consumers’ low-carbon purchase inclination of new energy vehicles, negative factors that hinder the stable development of transmissions must be avoided as far as possible. It is suggested that the government and new energy vehicle sellers use a variety of publicity means, and improve the performance of new energy vehicles, in essence, beyond the traditional fuel vehicles, in order to attract consumers. In this way, when communicators with conservative purchase inclinations have fuel cars whose service life expires, but they still need vehicles, the probability of consumers with conservative purchase inclinations turning into consumers with low-carbon purchase inclinations can be greatly improved.

Proposition 5.

The proportion of low carbon purchase inclination communicators I(∞) is a monotonically increasing function of low-carbon purchase inclination propagation rate α₁.

It is proved that I(∞) is a monotonically increasing function of the propagation rate α₁ of low carbon purchase inclination through the expression $\frac{\partial I(\infty )}{\partial {\alpha }_1}=\frac{{\alpha }_2\delta {\theta }_2}{(\phi +{\theta }_2){\theta }_1{({\alpha }_1+{\alpha }_2)}^2}>0$. When other parameters are fixed, the proportion of low-carbon purchase inclination communicators is related to the communication rate of low-carbon purchase inclination communicators, and with the increase in the communication rate of low-carbon purchase inclination communicators, the proportion of low-carbon purchase inclination communicators increases, that is to say, the two are positively correlated.

This paper assumes that there is a certain probability of transmission when low-carbon communicators come into contact with demanders, but it is not 100% certain that demanders have low-carbon purchase inclination after talking with them. They make a choice between fuel vehicles and new energy vehicles, or wait and see for a period of time before making a decision. When the proportion of consumers owning new energy vehicles reaches a certain scale, demanders are guided to become disseminators of low-carbon purchase inclination from the aspect of consumption behavior, and consumers have “herd psychology”, which enhances the transmission rate of low-carbon purchase inclination. If ${\alpha }_1>{\theta }_1-\phi$, the system can ensure that more demanders are converted into communicators of low-carbon purchase inclination and the tacit knowledge can be spread stably. Therefore, in order to effectively spread low-carbon purchase inclination, it is necessary to increase the contact rate between buyers of new energy vehicles and demanders, improve the understanding of the advantages of new energy vehicles, and advocate the idea of green environmental protection and sustainable development.

Proposition 6.

The proportion of low-carbon purchase inclination communicators I(∞) is a monotonously decreasing function of low-carbon purchase inclination transmission rate α₂.

It is proved that I(∞) is a monotonically decreasing function of the traditional propagation rate α₂ through the expression $\frac{\partial I(\infty )}{\partial {\alpha }_2}=\frac{-{\alpha }_1\delta {\theta }_2}{(\phi +{\theta }_2){\theta }_1{({\alpha }_1+{\alpha }_2)}^2}<0$. When other parameters are fixed, the proportion of low-carbon purchase inclination communicators is related to the communication rate of conservative purchase inclination communicators, and with the increase in the communication rate of conservative purchase inclination communicators, the proportion of low-carbon purchase inclination communicators gradually decreases, that is to say, the two are negatively correlated.

In the current automobile sales field, on the one hand, traditional fuel vehicles make up a considerable proportion; on the other hand, new energy vehicles have shown an explosive growth trend in recent years. Therefore, in this paper, the influence of fuel vehicle consumers cannot be ignored in the process of how to promote the transmission of low-carbon purchase inclination of new energy vehicle consumers. At present, the market share of fuel vehicles is still as high as 94%. For vehicle demanders, there will be more chances to contact with buyers of traditional fuel vehicles and be affected by conservative purchase inclinations. The higher the propagation rate of conservative purchase inclinations, the bigger the possibility of buying traditional fuel vehicles. In the process of communication between conservative purchase inclination communicators and low-carbon purchase inclination communicators, some conservative purchase inclination communicators will change into low-carbon purchase inclination communicators. However, if the propagation rate of conservative purchase inclination is too large, the proportion of conservative purchase inclination communicators is higher than that of low-carbon purchase inclination communicators, which is not conducive to the stable propagation of low-carbon purchase inclination in the system. Therefore, it is necessary to control the transmission rate of conservative purchase inclination. It is suggested that the government implement a carbon sink policy for automobile consumers, so that energy saving and emissions reduction are directly related to consumers’ economic benefits, thus attracting consumers’ attention and promoting the purchase of new energy vehicles.

5. Numerical Simulation Analysis

In this paper, specific examples are given and a parameter control method is used to more intuitively illustrate the evolution trajectory of the possible four groups of people in the transmission of low-carbon purchase inclination of new energy vehicle consumers over time under the action of different parameter values. The laptop used in the experiment was 64-bit Windows10 operating system with 8G memory, CPU Model: Intel(R) Core(TM) I7-4600M CPU @ 2.90 GHz 2.89 GHz. On the basis of this hardware, MatlabR2018b software was installed to draw graphs and perform numerical analysis.

5.1. Analysis of the Evolution of Four States of Low-Carbon Purchase Inclination

The parameters of the proposed are set as the following: φ = 0.2, c = 0.5, θ₁ = 0.22, θ₂ = 0.4, δ = 0.015, α₁ = 0.3, α₂ = 0.1. The evolution of the proportions of the four groups in the system over time is shown as Figure 2.

As shown in Figure 2, the proportion of demanders decreases gradually over time and is relatively low when it is stable, which indicates that tacit knowledge can be spread through the interaction between people with low-carbon purchasing inclination or conservative purchasing inclination and demanders. Demanders have changed into communicators of low-carbon purchase inclination or conservative purchase inclination. The number of people with conservative purchase inclination shows a decreasing trend, which indicates that the propagators of conservative purchase inclination are influenced by the people with low-carbon purchase inclination. Moreover, with the vigorous advocacy of government departments and the improvement of their own awareness of environmental protection, this group is transformed into the people with low-carbon purchase inclination. As time goes by, the number of abandoned people is on the rise as a whole, which is due to the fixed limit of the service life of the car and factors such as the users’ subjectively giving up using the car, so the number of abandoned people is bound to increase gradually. The proportion of people with low-carbon purchase inclination increases rapidly in the initial stage. In the calculation example, the transmission rate of low-carbon purchase inclination α₁ = 0.3 is higher than that of conservative purchase inclination α₂ = 0.1. The promotion of the transmission rate of low-carbon purchase inclination depends on the enhancement of people’s awareness of environmental protection in recent years and their recognition of the superiority of new energy vehicles. In addition, consumers who have bought fuel cars change their purchase inclination to buy and use new energy vehicles. These factors inevitably lead to a rapid increase in the number of people willing to buy low-carbon goods in the initial stage. When the proportion reaches a certain level, some people become abandoners, but eventually the system reaches stability in a certain state.

The setting of the initial parameter value of the system affects the purchase inclination of automobile consumers. Those who are more inclined to spread consumers’ low-carbon purchase inclination in the initial state accelerate the transmission speed and intensity of low-carbon purchase inclination. If there are more communicators of conservative purchase inclination in the initial state, the transmission of low-carbon purchase inclination is weakened, which is not conducive to the sustainable development of new energy vehicles. Therefore, if the government and relevant enterprises can adopt education and learning, vigorous publicity, active guidance, and other means to increase the probability of car buyers choosing new energy vehicles, it can reduce the situation that conservative purchase inclination continues to occupy the market, and achieve the purpose of positively guiding the purchase behavior of the car market.

5.2. Analysis of the Evolution of the Proportion of Purchasing Inclination Communicators

The parameters of the proposed are set as the following: φ = 0.2, c = 0.5, θ₁ = 0.22, θ₂ = 0.4, δ = 0.015, and other parameter changes are shown as

Table 1. Description of Transmission Rate Changes (1) (φ = 0.2, c = 0.5, θ₁ = 0.22, θ₂ = 0.4, δ = 0.015).

Experiment	Low-Carbon Transmission Rate α1	Conservative Transmission Rate α2	Description
Original Parameters	0.3	0.1	Initial Parameter Setting
Comparison1	0.65	0.1	Increase low-carbon transmission rates
Comparison2	0.3	0.15	Increase conservative transmission rate
Comparison3	0.65	0.15	Low-carbon and conservative transmission rates increase simultaneously

.

The evolution of the two purchase inclinations in the system over time is examined from three perspectives: increasing the propagation rate of low-carbon purchase inclinations, increasing the propagation rate of conservative purchase inclinations, and increasing both at the same time. The simulation results are shown as Figure 3.

As can be seen in Figure 3, when the propagation rate of low-carbon purchase inclination only is considered to increase, the proportion of low-carbon purchase inclination communicators rapidly increases, leading to the left deviation of the peak value. When the value of α₁ increases from 0.3 to 0.65, the peak time changes from t = 5 to t = 2.5. It indicates that the number of people with low-carbon purchase inclination increases rapidly at this time, while the proportion of conservative purchase inclination decreases significantly at the beginning. It shows that the communicators of conservative inclination are sensitive to the value of α₁ transmission rate. The whole system is dominated by the transmission of low-carbon purchase inclination, and the influence of conservative purchase inclination is relatively weak. When only the increase in the propagation rate of conservative purchase inclination is considered, there is no significant change in the trend that the proportion of communicators with low-carbon purchase inclination reaches the peak and the trend that they are in a stable state. However, the location of the peak value is obviously downward-offset, indicating that the increase in the propagation rate of conservative purchase inclination attracts the purchase inclination of demanders, thus greatly reducing the possibility of choosing to buy new energy vehicles. In the experiment, the initial state value of communicators with conservative purchase inclination increased and reached α₂ = 0.15. As the number of people with low-carbon purchase inclination increases, and those with conservative purchase inclination are influenced by the low-carbon consciousness of the government and surrounding people, they change their purchase inclination. Some of them give up their conservative purchase inclination and become abandoners, and some directly join the ranks of disseminators of low-carbon purchase inclination. As a result, the population with conservative buying inclination eventually stabilizes at a low level.

Increasing the transmission rate of low-carbon purchase inclination increases the proportion of groups with low-carbon purchase inclination, while reducing the proportion of groups with conservative purchase inclination. On the contrary, increasing the propagation rate of conservative purchase inclination increases the proportion of the group with conservative purchase inclination and reduces the proportion of the group with low-carbon purchase inclination. The two transmission rates lead to the polarized development of purchase inclination of the system, and the social action force is the most fundamental problem that makes the positive low-carbon behavior sustainable. At present, people have some understanding of low-carbon awareness, which has spread to a certain extent, but more social subjects need to take action, so as to truly, comprehensivelys and reliably realize the transformation from low-carbon awareness to low-carbon purchasing behavior. At present, people have some understanding of low-carbon awareness, which has spread to some degree, but there are still more measures to be taken, so as to truly, comprehensively, and reliably realize the transformation from low-carbon awareness to low-carbon purchasing behavior.

When both the low-carbon transmission rate and conservative transmission rate increase, the influence of the two kinds of purchase inclination in the system increases, and it has a certain neutralization effect on the stability of the system. Although it accelerates the speed at which low-carbon purchase inclination reaches the highest proportion, it decreases the value of its peak. As the initial parameter setting makes the influence of low-carbon purchase inclination greater than that of conservative inclination, the system as a whole still maintains the dominant position of low-carbon purchase inclination.

The parameters of the proposed are set as the following: c = 0.5, θ₁ = 0.22, θ₂ = 0.4, δ = 0.015, α₁ = 0.3, α₂ = 0.1, and other parameter changes are shown as

Table 2. Description of transformation rate change (2) (c = 0.5, θ₁ = 0.22, θ₂ = 0.4, δ = 0.015, α₁ = 0.3, α₂ = 0.1).

Experiment	Conversion Rate φ	Description
Original parameters	0.4	Initial Parameter Setting
Comparison1	0.9	Increased conversion rate
Comparison2	0.1	Reduced conversion rate

.

By increasing or decreasing the conversion rate of people with conservative purchase inclination to people with low-carbon purchase inclination, the evolution trend of the proportion of people with two kinds of purchase inclination is investigated. The simulation results are shown as Figure 4.

As can be seen in Figure 4, with the increase in the conversion rate, the proportion of people with low-carbon purchase inclination increases and the peak value shifts slightly to the left. This indicates that the peak speed is accelerated, but the proportion decreases slightly when it reaches the stable state in the later period. The possible reasons are the service life of the vehicle and the abandonment caused by a few subjective factors. The proportion of people with conservative purchase inclination decreases with the increase in the conversion rate, and the decrease speed is obviously accelerated, indicating that conversion rate has a reverse inhibition effect on people with conservative purchase inclination. At present, fuel cars account for a large proportion of car users. In order to improve consumers’ willingness to buy low-carbon cars, it is a very key and effective means to guide and infect the low-carbon awareness of people who now own fuel cars.

The increase in the conversion rate of conservative purchase inclination to low-carbon purchase inclination is conducive to increasing the proportion of low-carbon purchase inclination, effectively reducing the number of people with conservative purchase inclination and enhancing the trend of low-carbon purchase inclination spreading to a positive trend, which is the target direction of green and low-carbon behavior development. Comprehensive social forces, including the government, the masses, news, media, and enterprises, etc., should build an ecological environment suitable for the transmission of low-carbon purchase inclination tacit knowledge. This is conducive to the formation of green, low-carbon, and environmental values in society as a whole, to the positive and stable dissemination of consumers’ low-carbon purchase inclination, and to the sustainable development of new energy vehicles.

The parameters of the proposed are set as the following: φ = 0.4, c = 0.5, α₁ = 0.3, α₂ = 0.1, δ = 0.015. The parameters of thr abandonment rate of low-carbon purchase inclination and conservative purchase inclination are shown in

Table 3. Description of Abandonment Rate Change (φ = 0.4, c = 0.5, α₁ = 0.3, α₂ = 0.1, δ = 0.015).

Experiment	Low-Carbon Abandonment Rate θ1	Conservative Abandonment Rate θ2	Description
Original Parameters	0.22	0.4	Initial Parameter Setting
Comparison1	0.25	0.4	Increase the low-carbon abandonment rate
Comparison2	0.22	0.7	Increase conservative abandonment rate
Comparison3	0.25	0.7	Low-carbon and conservative abandonment rate increase simultaneously

.

The evolution of the two purchase inclinations in the system over time is examined from three perspectives: increasing the abandonment rate of low-carbon purchase inclinations, increasing the abandonment rate of conservative purchase inclinations, and increasing both at the same time. The simulation results are shown as Figure 5.

As can be seen in Figure 5, the increase in the abandonment rate of low-carbon purchase inclination significantly reduces the proportion of the group with low-carbon purchase inclination when it reaches a stable state, while it has no significant impact on the proportion of the group with conservative purchase inclination. When the abandonment rate of conservative purchase inclination is increased, the evolution curve of the group proportion of conservative purchase inclination deviates obviously to the left. This indicates that the number of conservative purchasing inclination groups decreases faster, but it has no significant impact on the proportion of low-carbon purchasing inclination groups. When the two groups increase at the same time, the number of both groups decreases obviously. If low-carbon purchase inclination can be sustained, effective, and stable, it is necessary to control the abandonment rate not to be too high. A high abandonment rate of low-carbon purchase inclination leads to a decrease in the number of people buying new energy vehicles, which is not conducive to the spread of tacit knowledge. The high abandonment rate of conservative purchase inclination directly affects the number of people with conservative purchase inclination, and also reduces the number of people who convert conservative purchase inclination to low-carbon purchase inclination, thus indirectly reducing the proportion of people with low-carbon purchase inclination. As for the service life of automobiles, which is the factor leading to abandonment, enterprises can extend the service life of automobiles through technological innovation, thus reducing the abandonment rate. In the case of subjective abandonment, it is suggested that the government strengthen positive guidance and eventually form a consensus environmental awareness of the whole social group, which is conducive to the sustainable and stable development of new energy vehicles and has far-reaching significance for the improvement of the ecological environment.

The differential dynamical system constructed in this paper is a deterministic system without random data and results. Therefore, each set of parameter values produces a deterministic and consistent result. Each evolution curve is examined for dozens of combinations of different parameters. The simulation results of each parameter combination show that the curve trend is roughly the same. In this paper, the simulation results use the most intuitive and clear group of many experiments.

6. Empirical Research

On the basis of the above theoretical research, the team members developed the questionnaire based on the WeChat mini program after nearly one year, in view of the current consumer groups on the purchase inclination of new energy vehicles for data collection and relevant empirical research.

6.1. The Questionnaire

Through the application of the WeChat platform interface, the questionnaire was designed based on the WeChat mini program, and the questionnaire data provided by participants were stored in the cloud database. The EChart tool was used to realize data visualization and analysis according to different query conditions.

According to the statistics, a total of 1465 people participated in the questionnaire survey, and 1254 people completed the questionnaire (the content of the questionnaire is long, 85% is normal). Excluding random questionnaires, the number of valid questionnaires was 1098. The following mainly analyzes the self-reported preferences of consumers of new energy vehicles based on questionnaire survey results.

6.2. Analysis of Survey Results

6.2.1. Demographic Characteristics of Respondents

The age distribution of respondents was divided into four categories: under 25 years old, 25–45 years old, 45–60 years old, and over 60 years old. Among them, males account for 46 percent, so the gender ratio is basically balanced. The proportion of people with a bachelor’s degree or above is 62%, and the educational structure is in line with the reality, as shown in Figure 6.

Only 10 percent of respondents have already bought new energy vehicles, 6 percent intend to, and 83 percent said they have not yet done so, as shown in Figure 7. This shows that the development of new energy vehicles in China is in its infancy. Although most people do not make purchases, they can objectively express to us what kind of new energy vehicles they need as consumers. This set of data also shows that consumers are gradually paying attention to the development of new energy vehicles and increasing their recognition of them, which indicates that people’s willingness to buy low-carbon vehicles is gradually increasing.

According to the statistics, 60% of respondents have different degrees of understanding of new energy vehicles. Seventy-one percent of respondents are very optimistic about the development prospects of new energy vehicles.

6.2.2. The Channel Statistics on the Interviewees’ Understanding of New Energy Vehicles

It takes a period of time for people to learn more about new energy vehicles from unknown conditions and transmit it by all kinds of means. The data obtained from the questionnaire show that most consumers know about this emerging technology either through contact with relatives and friends or through the Internet or media publicity, as shown in Figure 8.

In recent years, the government attaches importance to environmental protection and the construction and development of green ecology, and it increases efforts to promote new energy vehicles. By doing this, the government hopes to achieve energy conservation and emission reduction and improve air quality. For this reason, the government has done a lot of publicity work through media, the Internet, and other ways, and achieved very remarkable results. However, the process of publicity lacks the subjective experience of consumers, so most people are willing to believe the recommendation of relatives and friends, which transmits tacit knowledge widely. The higher the recognition of new energy vehicles, the more people are willing to buy low-carbon vehicles. In this way, tacit knowledge may spread positively and effectively in the direction of development. When it reaches a certain scale, it motivates the purchase behavior at the social level to achieve the purpose of environmental protection, energy conservation, and emission reduction.

Compared with the Internet, respondents are more likely to trust recommendations from friends and relatives. This may be because people think that information pushed by the Internet is more commercial, while recommendations from friends and relatives contain more emotions and subjective experience, which are more easily accepted by people. The communication and contact between people affect their purchase inclination, and even put the purchase behavior into action, which is the function of tacit knowledge dissemination. This set of data provides a strong basis for research on the necessity of tacit knowledge dissemination of consumers’ low-carbon purchasing inclination of new energy vehicles.

6.2.3. Price Preference

The data obtained through questionnaire survey can be presented to everyone in the form of a statistical graph, which can explain the problem more directly and clearly.

It can be clearly seen in Figure 9 that the price demand of consumers under the age of 25 is mainly less than 300,000 RMB, and more consumers can accept the new energy vehicles from 50,000 to 200,000 RMB. It is a reminder that manufacturers can focus on performance and vehicle configuration when targeting people under 25, and that even a slightly higher price can be accepted by them.

It can be clearly seen from Figure 10 that the proportion of respondents aged 25–45 who choose more than 200,000 RMB new energy vehicles is very small, which is different from the situation of the previous age group. At this stage, the cost of the car may be more important than the configuration.

It can be seen in Figure 11 that respondents aged 45–60 have a clearer choice of price, and prices above 200,000 RMB are not acceptable to this age group. However, the price below 200,000 RMB is evenly distributed, and the number of people in each price segment is almost the same. The most acceptable price is 50,000–100,000 RMB.

It can be clearly seen from Figure 12 that the results of the survey change for those over 60, with most respondents preferring cars costing less than 50,000 RMB. For those over 60, perhaps a cheap new energy car is a good choice. There are still some interviewees who can accept high-priced new energy vehicles. This shows that with the improvement of living standards, a small number of people over the age of 60 pursue a high-quality and high-comfort driving experience.

The statistics show that there is a big gap in price preference among respondents of different ages. Surprisingly, the respondents who chose high-priced NEVs were under 25 and over 60. The under-25s may simply be looking for premium prices, brand names, and comfort. Maybe it is a hope or a goal for them. People over 60 years old already have a certain economic strength and can choose high-quality new energy vehicles. Respondents aged 25 to 60 are more economical and practical. People in this age group are on the rise in their careers, as well as raising children and caring for the elderly, which may explain their focus on practicality.

6.2.4. Performance Preferences

Performance requirements of consumers for new energy vehicles directly affect their low-carbon purchase inclination, so it is necessary to conduct statistics on this, as shown in Figure 13.

The statistical results show that 69% of respondents are concerned about the range, which may be the disadvantage of new energy vehicles compared with traditional fuel cars. This is also the main reason why consumers hold a wait-and-see attitude towards new energy vehicles. At present, the power battery energy storage technology has been greatly improved; in addition, the popularity of charging piles and the development of fast-charging technology are gradually improving the range problem. This increases the rate at which people are willing to buy low-carbon vehicles. Another major concern you can see in Figure 13 is security. This is mainly reflected in battery short circuiting, kinetic energy recovery, temperature control, water problems, and many other aspects. It is suggested that power battery manufacturers and new energy vehicle manufacturers should not blindly pursue high endurance, but also improve safety performance, so that consumers’ low-carbon purchase inclination can be improved.

Through the questionnaire survey, it is also found that whether people choose to hold low-carbon purchase inclination and further purchase new energy vehicles is closely related to two factors. One is range and the other is safety. This is also a major reason for car buyers to hold a wait-and-see attitude. If new energy vehicle enterprises and power battery manufacturers can improve the key technologies in these two aspects, it will surely drive the holding rate of consumers’ low-carbon purchase inclination. Thus, it is recommended to reduce carbon emissions, to protect the environment and to achieve the purpose of green sustainable development.

7. Conclusions

This paper combines theory with practice and obtains people’s concerns about new energy vehicles through a practical questionnaire survey. The necessity of carrying out research on tacit knowledge dissemination of low-carbon purchase intention is illustrated with actual data. In this paper, through theoretical analysis of the new energy vehicle consumer groups of low-carbon purchase intention, spreads internal reasons. This study confirms that subjective factors that mobilize consumers’ low-carbon purchase intention can greatly improve people’s recognition of new energy vehicles, thus breaking the original wait-and-see attitude. This study puts forward reasonable suggestions for new energy vehicle enterprises and government policy orientation. Compared with other literatures in related fields, this paper contains both theoretical and empirical studies, while some of the literature is limited to a single empirical or theoretical study. By focusing on empirical research, the paper mainly explains the objective factors that affect consumers’ low-carbon purchase intention. Although the articles focusing on theoretical research have sufficient theoretical basis, they lack the support of actual data. The combination of the two is more persuasive and practical.

At present, facing global climate change and an energy crisis, all countries advocate low-carbon and green travel. In this context, the purchase and use of new energy vehicles shows an explosive growth trend. In this paper, buyers are divided into a low-carbon buying inclination group and a conservative buying inclination group. Under the influence of the government’s propaganda and positive guidance, the improved SIR model was constructed by taking into account the population flow of the transition from conservative purchase inclination to low-carbon purchase inclination. For the first time, differential dynamics and purchase inclination are combined. The problem is discussed in detail through differential dynamical analysis and numerical simulation. It is suggested that enterprises improve the driving range of new energy vehicles, the safety performance of power batteries, and the penetration rate of charging equipment from the technical level. This is an objective guarantee for the holding rate of consumers’ low-carbon purchase intention. It is suggested that the government strengthen the publicity of environmental protection awareness, enhance the subsidies to consumers of new energy vehicles and other means to promote consumers to subjectively recognize and accept new energy vehicles. Thus, the proportion of people willing to buy low-carbon increases, which lays a foundation for the active development of the tacit knowledge dissemination. The analysis of the theoretical model and data simulation can help new energy vehicle enterprises and governments make industry development plans in reality. The appeal analysis confirms that reasonable policy orientation can promote consumers’ low-carbon purchase inclination, enhance people’s awareness of environmental protection, and accept new energy vehicles from the perspective of subjective will. In order to understand and grasp what aspects of new energy vehicles people are interested in, the team members spent nearly one year developing a questionnaire based on the WeChat mini program and distributed it to 1098 respondents. The proportion of men and women in this survey is balanced, and the proportion of educational background is reasonable. The transformation from low-carbon purchase inclination to purchase behavior needs a transitional stage, and also needs some objective situational factors to assist and support. The evolution of purchase behavior will continue to be discussed in subsequent studies.