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The Compulsory Education Course Standards for Mathematics 2022 have highlighted the educational objectives of junior secondary mathematics by emphasizing the development of mathematical competence and practical learning. Model consciousness, as one of the fundamental mathematical competencies to be developed at the junior secondary level, can facilitate students' comprehension of the universal application of mathematics. Teachers of mathematics in junior high school should construct effective classroom activities based on the cognitive qualities of their students in order to enhance their mathematical model consciousness and comprehension of the substance of mathematics knowledge. This paper is a lesson study of the education of Congruent Triangles, and its purpose is to investigate strategies for fostering mathematical model consciousness among junior high school pupils.

The Verhulst model can be used to forecast the sequence, which is characterized as non-monotone and fluctuant sequence or saturated S-form sequence. According to the situation of national enrollment scale of college, this paper forecasts the quantity of students taking entrance examination to college with a Verhulst model with remedy based on data mining theories, and by the above model, some countermeasures are developed to the higher education of Henan province in China. (Contains 3 tables and 2 figures.) [This paper was partly supported by Financial Program for Core Teacher of Henan's University.]

For regions lack of strong ground motion records, a method is developed to predict strong ground motion by small earthquake records from local broadband digital earthquake networks. Sichuan and Yunnan regions, located in southwestern China, are se- lected as the targets. Five regional source and crustal medium parameters are inversed by micro-Genetic Algorithm. These parameters are adopted to predict strong ground motion for moment magnitude (Mw) 5.0, 6.0 and 7.0. Strong ground motion data are compared with the results, most of the result pass through ideally the data point plexus, except the case of Mw 7.0 in Sichuan region, which shows an obvious slow attenuation. For further application, this result is adopted in probability seismic hazard assessment (PSHA) and near-field strong ground motion synthesis of the Wenchuan Earthquake. [ABSTRACT FROM AUTHOR]

Traditional mathematical methods built around exactitude have limitations when applied to the processing of educational information, due to their uncertainty and imperfection. Alternative mathematical methods, such as grey system theory, have been widely applied in processing incomplete information systems and have proven effective in a number of fields. In this study, an assessment indicator system is developed, based on the MBA programme of Guangdong University of Foreign Studies (GDUFS), through statistics building on the initial indicators of the Association of MBA's assessment system for MBA programmes. The proposed system assesses the accredited indicators of the GDUFS' MBA programme using grey comprehensive evaluation methodology. The results accord with the actual situation, supporting the accuracy of the assessment model, research theory and methodology. In addition, this paper analyses and sorts degrees of satisfaction for programme indicators, with the adoption of the grey correlation analysis method, to provide a basis for decision-making.

Current debates about successful mathematics pedagogy suggest that mathematical learning and problem solving can be enhanced by using metaphors as they provide students with a tool for thinking. But assisting pre-service teachers to understand the importance of careful and accurate explanations for mathematical concepts remains an issue. This paper investigates how a mathematics teacher made use of models and metaphors to construct mathematical meanings within a transformational shift between less- and more-mathematical language. The Peircian model of semiosis was employed to identify the conceptual relationships in the metaphors and to analyse possible discrepancies between the literal meaning of metaphors, the teacher's intended meaning and the targeted mathematical concepts. The findings indicate that the syntactic, semantic, and pragmatic features of the language used in mathematics teaching play a significant role in student learning. Teachers' knowledge of students' prior understanding of mathematical meaning of related concepts and their knowledge of examples, models, and language that are pedagogically preferable jointly affect the quality of teaching.

Distribution process is the core of logistics enterprise system. Efficient distribution process is the key for enterprises to improve logistics service level, gain competitive advantage, and win customers. In order to reduce the design error of the system and ensure the effective operation of the system, this paper establishes the system model and analyzes the properties of the model through the evaluation and analysis of various resources of the distribution system. The future development of intelligent logistics system is not only the key for logistics enterprises to win competition, but also a new measure to promote China's economic development. This is not only a typical NP hard problem, but also a major challenge for the rational and scientific development of the intelligent logistics industry. Based on the previous theoretical research results, this paper intends to explore the intelligent logistics distribution route selection scheme by using mathematical modeling methods such as particle swarm optimization, so as to provide new technologies and methods for logistics distribution operation and management decision-making. The results show that compared with the traditional genetic algorithm, the accuracy of the improved particle swarm optimization algorithm is improved by 10.36%. This method effectively improves the operation cycle and link efficiency and achieves the purpose of optimization. The improved particle swarm optimization algorithm proposed in this paper is not only more suitable and effective for enterprise decision makers to deal with subjective judgments in an imprecise environment. It is also based on the evaluation sequence of each indicator of the alternative obtained from the evaluation and the comprehensive evaluation of all indicators. By weighting and considering the results, the best solution for enterprise logistics and distribution is selected. [ABSTRACT FROM AUTHOR]

Teaching quality is the lifeline of the higher education. Many universities have made some effective achievement about evaluating the teaching quality. In this paper, we establish the Students' evaluation of teaching (SET) discriminant analysis model and algorithm based on principal component clustering analysis. Additionally, we classify the SET by clustering the result of extracting the indexes through the principal component analysis (PCA), then we also test the rationality of the rating using Fisher's discriminant function. Finally, the model and algorithm are proved to be effective and objective according to the empirical analysis.

The degree of informatization of coal mine safety management is becoming higher and higher, and a large amount of information is generated in this process. How to convert the existing information into useful data for risk control has become a challenge. To solve this challenge, this paper studies the mathematical model of coal mine risk early warning in China based on data mining. Firstly, the coal mine risk data was comprehensively analyzed to provide basic data for the risk prediction model of data mining. Then, the adaptive neuro-fuzzy inference system (ANFIS) was optimized twice to build the coal mine risk prediction model. By optimizing the calculation method of the control chart, the coal mine risk early warning system was proposed. Finally, based on the coal mine risk early warning model, the software platform was developed and applied to coal mines in China to control the risks at all levels. The results show that the error of the optimized ANFIS was reduced by 66%, and the early warning error was reduced by 57%. This study aimed to provide implementation methods and tools for coal mine risk management and control, and data collected has reference significance for other enterprises. [ABSTRACT FROM AUTHOR]

Building a new development pattern based on the "double-cycle" is a major strategic plan of China. Under the background of the new development pattern of the "double-cycle" and the context of environmental constraints, this paper tries to explore the impact of marine economic development on marine cultural industry and marine innovation development, the extent of the impact of marine cultural industry on marine economic growth, and the internal relationship between them under the new development pattern of double circulation. In this paper, Fujian Province is taken as the research object to construct an indicator system of the marine culture development to reflect the living standard, employment level, and spiritual and cultural levels of people in the marine area, and the external influence of the marine economy and marine culture industry is taken as the indicator variable to measure the integrated development. The internal changes are regarded as the index to assess the integration level of the two, and the evaluation theoretical model of the dynamic evolution level of the marine economy and marine cultural industry is constructed. The vector autoregression model and impulse response function are used to study the interactive correlation between the growth of the marine economy and the development of the cultural industry. The results show the following: In the long run, there is a cointegration relationship between the marine culture industry and the gross ocean product (GOP), which is a long-term balanced and stable relationship. The development level of the marine economy and the development of marine culture industry are mutually influencing and promoting. [ABSTRACT FROM AUTHOR]

Preferential access to scarce resources can bring competitive advantages and better performance to enterprises. However, the existing literature has a relatively single research path on the influencing factors of enterprise resource access, which has lack of sufficient research from the perspective of multidimensional environment. In particular, as an important factor affecting enterprises' access to external resources, few studies have given empirical results on the impact of political factors such as government structure on enterprise resource access. Preferential access to scarce resources can bring competitive advantages and better performance to enterprises. However, the existing literature has a relatively single research path on the influencing factors of enterprise resource access, which lacks sufficient research from the perspective of multidimensional environment. In particular, as an important factor affecting enterprises' access to external resources, few studies have given empirical results on the impact of political factors such as government structure on enterprise resource access. Through the discussion of multidimensional environmental factors, this paper can provide theoretical reference for the reform of government institutions and the establishment of good political relations between enterprises and the government. Focusing on the multidimensional environment of government structure, political relations, and enterprise resource acquisition, this paper takes 129 enterprises in Central China as samples and uses the structural equation model to empirically verify the relationship between the formalization of government structure, liaison mechanism, decentralization, and enterprise resource acquisition, especially the easing effect of political relations. The results show that the formalization of government structure is promoting enterprises to obtain policy resources and financial resources; the liaison mechanism helps enterprises to obtain financial resources and market resources; decentralization has a significant positive impact on enterprises' access to policy resources and market resources; and political connection magnifies the positive effect of government structure on enterprise resource acquisition, but there are differences in different dimensions. [ABSTRACT FROM AUTHOR]

The article presents a study which derives the atmospheric boundary layer height and entrainment zone thickness in Lanzhou Shi and Yuzhong, China through the wavelet technology method and lidar measurements. The study accounts the derivation of the atmospheric boundary layer height and entrainment zone thickness to convective situations. It also applies microwave observations of both data sets with the help of a profiling radiometer and the parcel method.

Insulated plastic greenhouses (IPG) were a new type of facility emerging in production in China. The mechanism of construct parameters on the indoor solar radiation deserves further study. A mathematical model that can well describe the spatial and temporal distribution of solar radiation in the greenhouse was established. Based on this model, the effects of multiple construct parameters, such as insulation blanket shading, height–span ratio, greenhouse azimuth, and geographical latitude, on the indoor solar radiation of IPG were quantitatively specified. The results showed that the spatial and temporal distribution of inside solar radiation was highly variable along the span direction of IPG. And by analyzing the simulation data, it was found that for different heights of greenhouses, the corresponding optimal span is different. Therefore, in the construction of greenhouses, the appropriate height–span ratio should be selected according to the planting demand. And by simulating the inside solar radiation under different greenhouse azimuth angles, it was found that accumulated daily solar radiation in the greenhouse reaches the optimum value when the greenhouse azimuth angle is in the range of 0–20°. This paper can provide theoretical guidance for the design and optimization of structure parameters of IPG in China. [ABSTRACT FROM AUTHOR]

This paper uses Python programming to improve the existing price index method and calculate the integration level of the forest products market in China. Based on the model, the influencing factors of domestic forest product market integration were examined empirically. The results show that the integration degree of the forest product market in recent years lags behind the average level in China. In this paper, the improvement of the existing price index method can calculate the level of market integration more quickly and accurately, and this improvement has obvious advantages in the case of a large amount of data. In terms of development, the overall pattern shows an increasing trend, and the eastern, central, and western provinces are gradually converging, although the differences between provinces continue to expand. In terms of influencing factors, the coefficient of the local government's emphasis on forestry, the prosperity of international trade in forest products, and highway density were significantly positive factors, while the number of foreign investors and the railway density had no significant effects. In this paper, the optimization of the measurement method of market integration makes it easier for scholars to obtain the data on the level of market integration and promote in-depth research in the field of market integration. [ABSTRACT FROM AUTHOR]

The Summer Camp of Mathematical Modeling in China is a recently created experience designed to further Chinese students' academic pursuits in mathematical modeling. Students are given more than three months to research on a mathematical modeling project. Researchers and teams with outstanding projects are invited to the Summer Camp to present their findings and techniques. These projects are based on real-world problems and train students to apply their mathematical knowledge into practice. Students communicate their research ideas with experts, peers, and practitioners of relevant fields during the weeklong Camp. This paper will illustrate the Summer Camp of Mathematical Modeling's origin and motivation, organizational structure, development, sponsorships, and activities and modeling tasks.

The Sanjiang Plain located in Northeastern China is one of the major rice producing regions in the country. However, differing from the majority rice regions in Southern China, the Sanjinag Plain possesses a much cooler weather. Could the rice paddies in this domain be an important source of global methane? To answer this question, we calculated methane (CH4) emissions from the region by integrating remote sensing mapping with a process-based biogeochemistry model, Denitrification and Decomposition or DNDC. To quantify regional CH4 emissions from the plain, we first tested the model against a two-year dataset of CH4 fluxes measured at a typical rice field within the domian. A sensitivity test was conducted to find out the most sensitive factors affecting CH4 emissions in the region. Based on the understanding gained from the validation and sensitivity tests, a geographic information system (GIS) database was constructed to hold the spatially differentiated input information to drive DNDC for its regional simulations. The GIS database included a rice map derived from the Landsat TM images, which provided crucial information about the spatial distribution of the rice fields within the domain of 10.93 million hectares. The modeled results showed that the total 1.44 million ha of rice paddies in the plain emitted 0.43-0.58 Tg CH4 -C per year with spatially differentiated annual emission rates ranging between 100-800 kg CH4-C/ha, which are comparable with that observed in Southern China. The modeled data indicated that the high SOC contents, long crop season and high rice biomass enhanced CH4 production in the cool paddies. The modeled results proved that the northern wetland agroecosystems could make important contributions to global green-house gas inventory. [ABSTRACT FROM AUTHOR]

Background: According to the Chinese guidelines for lipid management (2023), evolocumab in combination with statins was recommended as secondary prevention of cardiovascular disease. However, because of the variation in the price of evolocumab and its different methods of confirming clinical efficacy, it was necessary to explore its economics and the impact of different methods of confirming efficacy on its economic studies. Objective: The purpose of this paper was to assess the cost-effectiveness of evolocumab with statins versus statins alone for patients with acute myocardial infarction(AMI) in China and to investigate the impact of different clinical effectiveness modeling approaches on economic outcomes. Methods: A Markov cohort state-transition model was used to estimate the incremental cost-effectiveness ratio (ICER) based on Chinese observational data on cardiovascular event rates, efficacy from the Asian subgroup of the FOURIER trial, cost and utility from the Chinese Yearbook of Health Statistics, health insurance data, and published studies conducted in China. This study conducted subgroup analyses for different populations and dosing regimens; sensitivity analyses for parameters such as cost, utility, and cardiovascular event rates; and scenario analyses on hospital hierarchy, time horizon, starting age, and price for statins. Results: ICERs ranged from 27423 to 214777 Chinese yuan(CNY) per QALY gained, all below the willingness-to-pay threshold of CNY 257094. Only when the time horizon became small, the ICERs were greater than the willingness-to-pay. The probabilities that adding evolocumab to statins was cost-effective ranged from 76 to 98%. When the time horizon became small, i.e. evolocumab was discontinued before the age of 75 (after conversion), the corresponding ICERs were almost always greater than the willingness-to-pay. ICERs for modelling approaches based on clinical endpoints were 1.34 to 1.95 times higher than ICERs for modelling approaches based on reduced LDL-C levels. Conclusions: From the Chinese healthcare and private payer perspectives, adding evolocumab to statin therapy in AMI patients is more likely to be a cost-effective treatment option at the current list price of CNY 283.8. However, evolocumab may not be cost-effective if used for shorter periods of time. The results based on different clinical effectiveness modeling approaches were significantly different. [ABSTRACT FROM AUTHOR]

In order to solve the problem of resource ecological compensation, this paper proposed a model of resource ecological compensation mechanism based on a rural leisure sports environment. The model is carried out in many places in China. The survey data involves 31 provinces, 10 years, and 43 indicators, with a total of 43 × 10 × 31 = 13,330 data. The preliminary basis of mechanism construction is summarized from four aspects. Finally, make full use of modern information technology to improve the network platform of the compensation mechanism, promote the efficient allocation and comprehensive utilization of ecotourism resources, and lay a solid foundation for establishing a reasonable and perfect resource ecological compensation mechanism and ensuring the long-term and stable operation of the mechanism. Through the experiment, it is found that the timely and effective publication of information can eliminate the inner estrangement between the two sides, so as to make the behavior of both sides more rational. A special information feedback department is established to deal with the opinions put forward by all compensation parties in tourism development, extract effective information, summarize and publish reasonable guidance information, and guide the compensation of both sides to an ideal balance through the feedback of this information. The effectiveness of the experiment is verified. [ABSTRACT FROM AUTHOR]

Bamboo has great economic values and is used extensively in many industries, and their natural distribution range was divided into 12 zones in China according to the temperature of their geographical distribution in previous works. Different bamboo species had significantly different abilities in low-temperature tolerance, which need to be considered carefully during ex-situ introduction. In this paper, we observed and evaluated the low-temperature damage of 19 bamboo species in winter, and measured the physiological changes of bamboo leaves. A total of 3060 leaf samples were obtained from 102 core collections in 34 bamboo species from the 5 regions of Chinese mainland for anatomical comparison, in order to screen out the key anatomical indicators related to their low-temperature tolerance and to establish a mathematical prediction model for bamboo introduction. The results showed that the low-temperature resistance of clustered bamboos was generally lower than that of the scattered bamboos. The decreased temperature led to the constant decrease of net photosynthetic rate and transpiration rate, but the increase of soluble sugar content in all bamboo species. There was no dormancy for all bamboo species in winter. The temperate bamboos showed lower photosynthesis as compared to tropical bamboos in winter. The leaf shape of bamboos was closely related to their distribution. A total of 13 leaf indicators were screened and more suitable to estimate the low-temperature tolerant abilities of bamboos and to predict their distribution. The MNLR (multiple nonlinear regression) mathematical model showed the highest fitting degree and the optimal prediction ability in the potential northernmost introduction range of bamboos. This study lay a foundation for bamboo introduction, and could also reduce the economic losses caused by the wrong introduction. [ABSTRACT FROM AUTHOR]

This paper investigates the interrelationships among local government debt, fiscal decentralization, and public health. The investigation begins by constructing a theoretical model to analyze the inherent connections between these variables. Subsequently, an empirical analysis is conducted using data from China between 2015 and 2021. The findings demonstrate a bidirectional relationship between fiscal decentralization, local government debt, and public health. Specifically, it is observed that an increase in local government debt has adverse effects on both fiscal decentralization and public health, while fiscal decentralization has a positive impact on public health. These insights are consistently validated through rigorous regression methodologies, affirming the robustness and significance of these relationships. [ABSTRACT FROM AUTHOR]

This study aims to provide useful insights for the Chinese government in dealing with healthcare fraud by creating an evolutionary game model that involves hospitals, third-party entities, and the government based on the government reward and punishment mechanism. This paper analyzes the evolutionary stability of each participant's strategy choice, discusses the influence of each element on the tripartite strategy choice, and further analyzes the stability of the equilibrium point in the tripartite game system. The results show that (1) the government increasing fines on hospitals is conducive to compliant hospital operations, and the incentive mechanism has little effect on such operations; (2) the lack of an incentive mechanism for third parties results in false investigations by third parties; and (3) rewards from higher levels of government promote strict supervision by local governments, but that the high cost of supervision and rewards for hospitals inhibits the probability of strict supervision. Finally, Matlab 2020a is used for simulation analysis to provide a reference for the government to improve the supervision of healthcare fraud. [ABSTRACT FROM AUTHOR]

Online medical consultation (OMC) is generating considerable interest among researchers and practitioners due to the mandatory quarantine measures implemented during the COVID-19 pandemic in China. However, the acceptance rate of OMC has declined over time. This paper aims to empirically investigate OMC acceptance using a proposed research model by integrating the technology acceptance model (TAM) with trust and its antecedent variables. A quantitative self-administered cross-sectional survey was conducted to collect data from 260 healthcare consumers. A partial least squares structural equation modeling method was used to examine the data. Results revealed that healthcare consumers' behavioral intention was influenced by attitudes, while perceived usefulness and trust significantly influenced behavioral intention through attitude as a mediator. In addition, perceived risk, perceived privacy protection, network externalities, cognitive reputation, and interactivity directly influenced trust. Overall, the research model explained 50% of the variance in attitude and 71% of the variance in behavioral intention. The study's findings should provide useful insights into making effective design, development, and implementation decisions for OMC services. [ABSTRACT FROM AUTHOR]

Objective To give an overview of the recent history of publications on mathematical modelling of infectious diseases in the Chinese literature, and a more detailed review of the models on severe acute respiratory syndrome (SARS). Method Literature review through the Chinese CAJ full-text database. Results The number of Chinese publications on mathematical modelling has at least quadrupled since the SARS epidemic in 2003. This increase not only included papers on SARS, but also on various other infectious diseases, indicating a substantial expansion of modelling experience in China. Typical problems of most studies were poor availability of data and lack of involvement of disease experts and decision-makers rendering the studies less useful for policies on control. Conclusions We expect that the recent experience on modelling and current better access to and exchange of epidemiological data have paved the way for a more substantial role of this discipline during possible future outbreaks of infectious diseases. By making Chinese modelling initiatives more visible to non-Chinese readers, we hope to attract more international collaborators. [ABSTRACT FROM AUTHOR]

Few studies have considered the information in the frequency domain to detect the structural breaks in financial markets. This paper provides a mixed model that integrates BEMD, AFD and Chow test to study the fluctuation characteristics of the soybean futures price. Due to the application of AFD, the mixed model can detect the structural breaks of the price fluctuation through obtaining the high-resolution information in the frequency domain. According to our results, in general, the soybean futures price in China is mainly determined by IMF11, followed by IMF9, IMF8 and IMF7, and there exist many structural breaks of different IMFs. Interestingly, national macro-controls have opposite effects at IMF8 and IMF11. The results show the effectiveness of the proposed mixed model for detecting structural breaks of financial markets in frequency-domain by revealing the impact of external events on the soybean futures price at multi-scales. [ABSTRACT FROM AUTHOR]

The sustainable development of smart community is the key to China's grassroots governance and also the general trend of China's urban modernization. In the supervision of the smart community, the optimization of the behavior of the regulatory subject cannot be separated. Previous studies have focused more on how subjects participate in supervision and less on the behavior of stakeholders in the game. This paper analyzes the game behavior of regulatory participants in the process of sustainable development of smart community and studies the optimization strategy of regulatory behavior according to the game behavior logic among participants. The results show the following. (i) Government behavior plays a leading role in supervision. (ii) When the government invests resources in the screening of third-party evaluation agencies and service purchase and mainly adopts policy punishment methods for stakeholders with rent-seeking behavior, the probability of regulatory participation stakeholders' positive behavior is the greatest. (iii) The improvements should be made from the aspects of information network construction, the refinement of reward and punishment measures, and the improvement of evaluation party access rules. This not only helps to enhance the good supervision situation of the supervision enthusiasm of the participants but also can realize the self-discipline operation of the smart community and enhance the responsibility consciousness of the evaluation institutions. [ABSTRACT FROM AUTHOR]

Artificial intelligence is widely used in mathematical modeling. The technical means in mathematical modeling are more and more diversified, especially the application of artificial intelligence algorithm greatly promotes the development of mathematical modeling. In recent years, because of its great influence on the fuel consumption, output power and exhaust performance of automobiles, the control strategy has become a research hotspot and focus in automobile R&D industry. Therefore, based on the relevant research results in recent years, after studying and analyzing the typical control strategies of hybrid vehicles, this paper finally puts forward the energy management strategy of hybrid vehicles based on model predictive control (MPC), and strives to contribute to the academic research of energy management strategies of hybrid vehicles. [ABSTRACT FROM AUTHOR]

Printed circuit board (PCB) orthogonal packing problems derive from the massive circuit board production process in the electronic industry. In the early stage, it mainly relied on human experiences to make decisions on how to make the most of each sheet while meeting customers' orders. Up till now, researchers in enterprises and academic circles are still trying to explore effective mathematical models and feasible optimization methods. In most cases, what PCB companies generally face is the orthogonal layout decision, which considers positioning each rectangle PCB piece (PCB-P) on a rectangle sheet board (panel) in an ideal way so that each panel has the minimal remains with the most PCB-Ps. In this paper, multi-round gradual packing methods (MGPMs) are proposed based on the idea of combinatorial optimization and dynamic programming. MGPMs include the depth priority-based method (MGPM-DP) and breadth priority-based branch-and-prune method (MGPM-BC). The former has the advantage of finding better solutions, while the latter has the advantage of consuming short computational time. Through extensive computational tests on real data from a PCB production enterprise in China, both MGPM-DP and MGPM-BC have achieved noticeable and satisfactory results compared with the simplex method, dynamic programming method, and a widely used industrial software (Yuanbo) in China. [ABSTRACT FROM AUTHOR]

In view of the uncertainty and intermittency of wind power, this paper proposes an optimal economical dispatch (ED) model and develops a method to estimate risk and manage hybrid power systems (traditional + wind~power~systems) for the short-term (24 h) operations. The model and the method have taken into account the large wind power penetration and the wind variability. The particle swarm optimization (PSO) refid="ref1"/ algorithm with constraints is applied to solve the ED problem. Value at risk (VaR) refid="ref2"/ and integrated risk management (IRM) refid="ref3"/ are used separately to assess the risk, so that an optimal tradeoff between the profit and risk is made for the system operations. The model and the method are tested on the standard IEEE 30-bus power system and network in Shanghai. The validity of the model and the method has been approved. [ABSTRACT FROM PUBLISHER]

Global warming has brought about enormous damage, therefore, some scholars have begun to conduct in-depth research on peak carbon dioxide emissions and carbon neutrality. In this paper, based on the background of China's upgrading industrial structure and energy structure, we establish a delayed two-dimensional differential equation model associated with China's adjustment of industrial structure. Firstly, we analyze the existence of the equilibrium for the model. We also analyze the characteristic roots of the characteristic equation at each equilibrium point for the model, then, we analyze the stability of the equilibrium point for the model according to the characteristic root, and discuss the existence of Hopf bifurcation of the system by using bifurcation theory. Secondly, we derive the normal form of Hopf bifurcation by using the multiple time scales method. Then, through the official real data, we present the range of some parameters in the model, and determine a set of parameters by reasonable analysis. The validity of the theoretical results is verified by numerical simulations. Finally, we use the real data to forecast the time of peak carbon dioxide emissions and carbon neutralization. Eventually, we put forward some suggestions based on the current situation of carbon emission and absorption in China, such as planting trees to increase the growth rate of carbon absorption, deepening industrial reform and optimizing energy structure to reduce carbon emissions. [ABSTRACT FROM AUTHOR]

The cold and high altitude Tibetan area (hereinafter referred to as Tibetan area) is a special geographical area in western China. Whether the local economic development and EE (ecological environment) are coordinated or not directly affects the sustained and healthy economic and social development of the whole Tibetan area. Firstly, this paper discusses the relationship between economic growth and EE on the basis of existing related theoretical research. Then, 15 indicators of economic system and environmental system were selected, and the coupling degree model and coupling coordination degree model were constructed to quantitatively analyze the dynamic model of regional economic and EE coupling and coordinated development in Tibetan areas from 2010 to 2020. The research found that in the past 11 years, the comprehensive index of EE of four regions in Tibetan areas has changed from 0.5 to 0.6, and the comprehensive index of the economy of four regions in Tibetan areas has changed from 0.51 to 0.74. On the whole, the coordination degree and coordinated development degree of green development in Tibetan areas have changed at the same time compared with the years, and since 2016, both of them have had the same trend and both of them are beginning to develop in a good direction. Since 2017, the economic development has been relatively advanced, while the EE has lagged behind, showing a fluctuating state, while the level of coordinated development has been continuously improved. This study has certain reference value for promoting ecological protection and green development in Tibetan areas. [ABSTRACT FROM AUTHOR]

In response to the high unemployment rates of university graduates, Asian governments are encouraging their universities to develop a more practice-oriented curriculum. The aim is to provide better-qualified graduates, who will meet the needs of industry. The Duale Hochschule Baden-Wuerttemberg (DHBW) supports this development, through internationalizing cooperative education programs at Asian universities, based on its successful study model. This paper focuses on comparing the DHBW with two Asian universities: Walailak University in Thailand and Southeast University in China. Descriptive case studies for the two universities, using a multiple case design, were mapped to the key success factors of the DHBW, in particular achieving practical experience and the role of industry. The data for the case studies originated from semi-structured interviews in a focus group setting with 36 academics, government officials, cooperative education bodies and industry representatives. The aim was to assess the opportunities and limitations for implementing the DHBW model. [ABSTRACT FROM AUTHOR]

Zhijin county is one of the areas with fragile geological environment and frequent natural disasters in China. In recent years, with the intensification of human activities, the geological environment has been continuously damaged, causing geological disasters of different scales and serious life threats and property losses to people. Therefore, the purpose of introducing this mathematical model is to make the data more intelligent and professional by combining the data of geological disasters in mathematics. Based on the geological disaster monitoring, warning and decision support system of Guizhou province, this paper takes Zhijin county as the research object and uses Oracle database to manage the data by building and designing data structure and data model. The results show that geological hazard assessment can not only provide reliable data for analysis and research, but also provide reference value for similar database construction: (1) to construct spatial data model to realize effective correlation between spatial data and business data. (2) spatial entity objects have the characteristics of multi-dimension and polysemy, and "relational-object" mathematical modelling is adopted. [ABSTRACT FROM AUTHOR]

Leaf area of dried Flue-cured tobacco is a reflection of climate and stage of growth of fresh tobacco in field; it also serves as the foundation for calculating a number of significant physical properties of tobacco. So the purpose of this paper was to establish a model to estimate the leaf area of dried Flue-cured tobacco in China from linear dimensions. Three Hundred eight tobacco leaves from different growing area and stalk position were sampled randomly and separated for model selection among linear, proportional and power model type and external evaluation individually. Results showed that there was a significant and strong correlation between leaf area and length×width, The equation LA = 0.495(L×W), where LA is the leaf area and L×W is the product of leaf length and width, was optimum and adequate for the estimation of leaf area of dried tobacco in China examined by Fisher’s test, Akaike delta information criterion (AIC) and Bayesian information criterion (BIC). Growing area and stalk position had minor effect on the parameter before (L×W). The equation can sufficiently predict the area of leaf for external evaluation. [ABSTRACT FROM AUTHOR]

"Mathematics Curriculum Standard for Ordinary Senior High School" points out that mathematical modelling literacy is the literacy of abstracting real problems mathematically, expressing problems with mathematical language, and building models with mathematical methods to solve problems. It assesses the amount to which students who are about to finish compulsory schooling have the knowledge and aptitude to deal with future life issues, based on the notion of lifelong learning. The usage of a local integrated development environment requires a number of complex processes, including installation and setup, as well as the procurement of necessary hardware. In reality, in order to nurture students, the core literacy of mathematics is to completely execute quality education, further identify the training and development direction of talents, and infiltrate the core literacy material into junior high school mathematics classroom instruction. For such a large-scale international education measurement project, the research and development of test questions is very important. Therefore, detailed technical consideration has been carried out and test volumes have been designed that are relatively suitable for different countries. The test questions are closely related to life, while there are few questions related to real situational problems in the test, which are mathematically processed first. Due to the international background of evaluation, it is a great challenge for researchers to realize the localization of evaluation on the basis of adapting to the domestic situation. At the same time, there is no scientific and perfect mathematical modelling literacy evaluation system in China's basic education research. How can middle school front-line teachers better evaluate students' mathematical modelling literacy? As a result, it is critical to develop a scientific and quantitative mathematical literacy measurement model that will aid in the teaching and research of mathematical modelling by middle school front-line teachers, as well as contributing theoretically to the evaluation and research of mathematical modelling literacy in China. Therefore, based on mathematics literacy evaluation, this paper studies the hierarchy of the IoT and the measurement and evaluation model of mathematics literacy based on the IoT, as well as its enlightenment to the compilation of mathematics academic test questions in China. [ABSTRACT FROM AUTHOR]

This paper is the second in a two-part series on the concavity-convexity of the distribution system security region (DSSR). In Part I, the concave-convex characteristics and mechanism of DSSR are revealed by observing many case grids. In Part II (this paper), the concave-convex principle of DSSR is revealed through mathematical deduction. Firstly, the relevant concepts of sub-regions are proposed, and a DSSR model based on the union of sub-regions is developed. Secondly, the concave-convex principle of DSSR is proposed. The proposed criteria show that the security region of a distribution system with a single load transfer path for each feeder is convex, while that with multiple load transfer paths for some feeders can be concave or convex. Thirdly, the proposed criteria are deduced mathematically. Fourthly, based on the criteria, a method is proposed to judge whether a DSSR is concave or convex. Fifthly, the proposed criteria and method are verified through several cases, and the DSSR concavity-convexity of real distribution systems in China is also analyzed. Finally, the applications of DSSR concavity-convexity are illustrated. This work lays a mathematical foundation for the research of the topological properties of DSSR and is also useful for the application of DSSR. • The DSSR mathematical model based on the union of sub-regions is developed. • Three criteria are proposed and proved, revealing the concave-convex principle of DSSR. • A judgment method for DSSR concavity-convexity is proposed based on these criteria. • The DSSR concavity-convexity of real distribution systems in China is analyzed. • The application values of DSSR concavity-convexity are demonstrated. [ABSTRACT FROM AUTHOR]

Purpose: The paper is going to analyze that there are dynamic quantitative relationships between Chinese urbanization and service industry. Design/methodology/approach: According to the index number of value-added of service industry and town population/ total population ratio during the year of 1978 to 2012 in China, the paper is designed with models which are analyzed by ADF test, co-integration test, error correction model and Granger causality test, finally get the conclusion. Findings: The paper achieves the two conclusions, one is that urbanization is the important power of service industry's growth; the other is that the level of urbanization improves the level of service industry recently. Originality/value: Chinese urbanization and service industry have close relationship, and they also have dynamic changes. The paper studies their dynamic changes through collecting a lot of data from the year 1978 to 2010 and developing models to make quantitative analysis, for example, tables and quotations in the paper are the best proof. At last, the paper also puts forward some suggestions after get the conclusion that Chinese urbanization is the motive power to the growth of service industry. [ABSTRACT FROM AUTHOR]

Background: This paper reports on a research study that aims to identify and explain barriers to knowledge sharing (KS) in the provision of healthcare referral services in Chinese healthcare organisations. Design: An inductive case study approach was employed, in which 24 healthcare professionals and workers from four healthcare organisations in the province of Hubei, Central China, were interviewed using semi-structured scripts. Results: Through data analysis, 14 KS barriers emerged in four main themes: interpersonal trust barriers, communication barriers, management and leadership barriers, and inter-institutional barriers. A cause-consequence analysis of the identified barriers revealed that three of them are at the core of the majority of problems, namely, the absence of national and local policies for inter-hospital KS, lack of a specific hospital KS requirement, and lack of mutual acquaintance. Conclusions: To resolve KS problems, it is of great importance that healthcare governance agencies, both at the national and regional levels, take leadership in the process of KS implementation by establishing specific and strong policies for inter-institutional KS in the referral process. This paper raises important issues that exceed academic interests and are important to healthcare professionals, hospital managers, and Information communication technology (ICT) managers in hospitals, as well as healthcare politicians and policy makers. [ABSTRACT FROM AUTHOR]

Purpose: As one of the most important overhead capital of urban economics and social development, the sustainable development of urban infrastructure is becoming a key issue of prosperous society growing. The purpose of this paper is to establish a basic model to analysis certain infrastructure project's sustainable construction and operation. Design/methodology/approach: System dynamics is an effective stimulation method and tool to deal with such complex, dynamics, nonlinear systems, which could be used in analyzing and evaluating all aspects of infrastructure sustainability internally and externally. In this paper, the system is divided into four subsystems and 12 main impact indicators. Through setting the boundary and other basic hypothesis, this paper designs the basic causal loop diagrams and stock & flow diagrams to describe the relationship between variables and establish a quantifiable structure for the system. Findings: Adopting a sewerage treatment in China as a case to test our model, we could conclude that the model of internal sustainable subsystem is reasonable. However, this model is a basic model, and it need to be specific designed for the certain project due to the diversity of infrastructure types and the unique conditions of each projects. Originality/value: System Dynamics (SD) is widely used in the study of sustainable development and has plentiful research achievements from macro perspective but few studies in the microcosmic project systems. This paper focuses on the unique characteristics of urban infrastructure in China and selects infrastructure project which is based on micro-system discussion. The model we designed has certain practical significance in policy setting, operation monitoring and adjustment of the urban projects with high rationality and accuracy. [ABSTRACT FROM AUTHOR]

Porter hypothesis states that environmental regulation may lead to win-win opportunities, that is, improve the productivity and reduce the undesirable output simultaneously. Based on directional distance function, this paper proposes a novel dynamic activity analysis model to forecast the possibilities of win-win development in Chinese industry between 2011 and 2050. The consistent bootstrap estimation procedures are also developed for statistical inference of the point forecasts. The evidence reveals that the appropriate energy-saving and emission-abating regulation will significantly result in both the net growth of potential output and the increasing growth of total factor productivity for most industrial sectors in a statistical sense. This favors Porter hypothesis. [ABSTRACT FROM AUTHOR]

This paper develops a new grey prediction model with quadratic polynomial term. Analytical expressions of the time response function and the restored values of the new model are derived by using grey model technique and mathematical tools. With observations of the confirmed cases, the death cases and the recovered cases from COVID-19 in China at the early stage, the proposed forecasting model is developed. The computational results demonstrate that the new model has higher precision than the other existing prediction models, which show the grey model has high accuracy in the forecasting of COVID-19. [ABSTRACT FROM AUTHOR]

The demand for healthy old-age care is growing rapidly in China. The traditional old-age care model can no longer meet elderly patients' demands for medical care and old-age care. To promote the development of medical care-integrated old-age care, a solution covering multiple aspects is necessary. In the context of the global development of healthy aging, China recently issued many policies to integrate old-age care with medical care, establishing protection for a large number of disabled elderly people. The Integrated Care of Older People (ICOPE) project is an international program developed by the World Health Organization. This paper reviews China's medical and old-age care integration model and the opportunities and challenges in implementing the ICOPE in the context of healthy aging in China. [ABSTRACT FROM AUTHOR]

Synchrophasors, widely used in the monitoring and analysis of power systems, evolved from the phasor method presented by Charles Proteus Steinmetz in 1893. The phasor method is a mathematical method for solving linear sinusoidal steady-state circuits and time-varying electromagnetic fields. This paper traces the history and diffusion of the phasor method in the discipline of electrical engineering in China. In 1914, Sidney Roby Sheldon, an American teacher at the Government Institute of Technology of the Communications Ministry, Shanghai, China, introduced the phasor method to his students in his Alternating Currents course. The textbook used was Elements of Electrical Engineering (Volume II) by William Suddards Franklin and William Esty. In 1920, The Electrical Magazine published a paper “Complex number and its application” by Sijiu Shi (editor of the electrical engineering section of this periodical). This is the earliest example found of Chinese literature introducing the phasor method. In the 1930s, Principles of Alternating Currents, an American electrical engineering textbook that includes the phasor method, was translated by Chinese scholars; this Chinese version promoted the use of the phasor method in China's electrical engineering field. Alternating Current Circuits, authored by the Chinese university professor Pen Tung Sah and published in 1948, may be the earliest example of the phasor method being included in a Chinese electrical engineering textbook; it played an important role in popularizing the phasor method in China. [ABSTRACT FROM AUTHOR]

Scarlet fever is an acute respiratory infectious disease and the incidence rate is increasing from 2011 throughout the world. In this paper, the mathematical models are proposed, which incorporate both direct transmissions and indirect transmissions of scarlet fever. The threshold conditions for disease invasion are obtained in terms of the basic reproduction number. The peak value, final size and epidemic time in a seasonal prevalence are investigated numerically. Furthermore, the effects of seasonal fluctuations on disease outbreak are also studied on the basis of real data in China. [ABSTRACT FROM AUTHOR]

Standard scheduled flight block time (SBT) setting is of great concern for Civil Aviation Administration of China (CAAC) and airlines in China. However, the standard scheduled flight block times are set in the form of on-site meetings in practice and current literature has not provided any efficient mathematical models to calculate the flight block times fairly among the airlines. The objective of this paper is to develop and solve a mathematical model for standard SBT setting with consideration of both fairness and reliability. We use whale optimization algorithm (WOA) and an improved version of the whale optimization algorithm (IWOA) to solve the SBT setting problem. A novel nonlinear update equation of convergence factor for random iterations is used in place of the original linear one in the proposed IWOA algorithm. Experimental results show that the suggested approach is effective, and IWOA performs better than WOA in the concerned problem, whose solutions are better compared to the flight block times released by CAAC. In particular, it is interesting to find that MSE, RMSE, MAE, MAPE and Theil of the reliability in 60%–70% range are always the smallest and the average fairness of airlines is better than that of 60%–75% range. The model and solving approach presented in this article have great potential to be applied by CAAC to determine the standard SBTs strategically. [ABSTRACT FROM AUTHOR]

Purpose The purpose of this paper is to contribute to the literature in three ways: first, the authors investigate the impact of the sampling errors on optimal portfolio weights and on financial investment decision. Second, the authors advance a comparative analysis between various domestic and international diversification strategies to define a stochastic optimal choice. Third, the authors propose a new methodology combining the re-sampling method, stochastic optimization algorithm, and nonparametric stochastic dominance (SD) approach to analyze a stochastic optimal portfolio choice for risk-averse American investors who care about benefits of domestic diversification relative to international diversification. The authors propose a new portfolio optimization model involving SD constraints on the portfolio return rate. The authors define a portfolio with return dominating the benchmark portfolio return in the second-order stochastic dominance (SSD) and having maximum expected return. The authors combine re-sampling procedure and stochastic optimization to establish more flexibility in the investment decision rule.Design/methodology/approach The authors apply the re-sampling procedure to consider the sampling error in the optimization process. The authors try to resolve the problem of the stochastic optimal investment strategy choice using the nonparametric SD test by Linton et al. (2005) based on sub-sampling simulated p values. The authors apply the stochastic portfolio optimization algorithm with SSD constraints to define optimal diversified portfolios beating benchmark indices.Findings First, the authors find that reducing sampling error increases the dominance relationships between different portfolios, which, in turn, alters portfolio investment decisions. Though international diversification is preferred in some cases, the study’s results show that for risk-averse US investors, in general, there is no difference between the diversification strategies; this implies that there is no increase in the expected utility of international diversification for the period before and after the 2007-2008 financial crisis. Nevertheless, the authors find that stochastic diversification in domestic, global, and Europe, Australasia, and Far East markets delivers better risk returns for the US risk averters during the crisis period.Originality/value The originality of the idea in this paper is to introduce a new methodology combining the concept of portfolio re-sampling, stochastic portfolio optimization with SSD constraints, and the nonparametric SD test by Linton et al. (2005) based on subsampling simulated p values to analyze the impact of sampling errors on optimal portfolio returns and to investigate the problem of stochastic optimal choice between international and domestic diversification strategies. The authors try to prove more coherence in the portfolio choice with the stochastically and the uncertainty characters of the paper. [ABSTRACT FROM AUTHOR]

Purpose: There are several routes between some OD pairs in the urban rail transit network. In order to carry out the fare allocating, operators use some models to estimate which route the passengers choose, but there are some errors between estimation results and actual choices results. The aim of this study is analyzing the passenger route choice behavior in detail based on passenger classification and improving the models to make the results more in line with the actual situations. Design/methodology/approach: In this paper, the passengers were divided into familiar type and strange type. Firstly passenger integrated travel impedance functions of two types were established respectively, after that a multi-route distribution model was used to get the initial route assignment results, then a ratio correction method was used to correct the results taking into account the transfer times, crowd and demand for seats. Finally, a case study for the Beijing local rail transit network is shown. Findings: The numerical example showed that it is logical to take passenger classification and the model and algorithm is effective, the final route choice results are more comprehensive and realistic. Originality/value: The paper offers an improved model and algorithm based on passenger classification for passenger route choice in the urban rail transit network. [ABSTRACT FROM AUTHOR]

The real estate industry is one of the fast growing industries in many developing countries such as China and India. The Chinese real estate industry has gone through many reforms from offering housing as part of its social welfare system, to the current capitalist model based on demand and supply. Due to these reforms and the shortage of lands for development in China's urban cities, many Chinese property firms have resorted to land banking in order to secure land property for future developments. However, in China, land speculation is considered illegal, while failure to purchase the suitable land for future developments will hinder the real estate developers’ future business and growth. The purpose of this paper is to develop a decision making model for property developments in their land banking decisions and strategies. The paper employed mathematical modeling and Monte Carlo simulation to examine our decision model, and further validated our results by conducting the simulation by using China Vanke Co. Ltd as a case study. This study is one of the first few studies that develop a decision model for land banking in China. It also helps real estate enterprises to make rational and dynamic decision in the current dynamic property market. [ABSTRACT FROM PUBLISHER]

Background The rising incidence of thyroid cancer (TC) has generated growing concern globally; yet there are no studies examining whether this incidence was followed by a rise in related mortality. We aimed to comprehensively quantify current trends and future projections of TC incidence and mortality, and to explore the association between the TC burden and socioeconomic inequality in different income strata. Methods We obtained incidence and mortality data on TC and population from the 2019 Global Burden of Disease (GBD) study and the United Nations' World Population Prospects 2022. We applied an age-period-cohort (APC) model to estimate the overall annual percentage change (net drift) and age, period, and cohort effects from 1990 to 2019, and also constructed a Bayesian APC model to predict the TC burden through 2030. Results Over a third of global TC cases belonged to the high-income group. From 1990 to 2019, net drifts of TC incidence were >0 in all income groups, while a modest reduction (net drift <0) in mortality was observed in most income groups, except for the lower-middle-income group. Unfavourable age, period, and cohort effects were most notable in Vietnam, China, and Korea. The age-standardised incidence rate (ASIR) is predicted to increase whereas the age-standardized mortality rate (ASMR) is expected to decrease globally between 2020 and 2030, with geographic heterogeneity being detected across income groups. We observed a positive correlation between ASIR and universal health coverage index and health worker density, but a negative one between ASMR and the two indicators, primarily in upper-middle-income and high-income countries. Conclusions Opposite patterns in incidence and mortality of TC raise concerns about overdiagnosis, particularly in upper-middle-income and high-income countries. Discrepancies in the distribution of health service accessibility, including diagnostic techniques and therapeutic care, should be addressed by narrowing health inequalities in the TC burden across countries. [ABSTRACT FROM AUTHOR]