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The purpose of this paper is to introduce an effective method for two-dimensional inverse heat conduction problems.

The variational iteration method (VIM) is used to solve two-dimensional inverse heat conduction problems and restore boundary conditions in heat conduction.

Numerical results compared with other methods show that the present method is remarkably effective for solving two-dimensional inverse heat conduction problems. This method is a very promoting method, which will be certainly found wide applications.

The VIM is applied to two-dimensional inverse heat conduction problems for the first time.

The purpose of this paper is twofold: first, to explore how China uses a social credit system as part of its “data-driven authoritarianism” policy; and second, to investigate how datafication, which is a method to legitimize data collection, and dataveillance, which is continuous surveillance through the use of data, offer the Chinese state a legitimate method of monitoring, surveilling and controlling citizens, businesses and society. Taken together, China’s social credit system is analyzed as an integrated tool for datafication, dataveillance and data-driven authoritarianism.

This study combines the personal narratives of 22 Chinese citizens with policy analyses, online discussions and media reports. The stories were collected using a scenario-based story completion method to understand the participants’ perceptions of the recently introduced social credit system in China.

China’s new social credit system, which turns both online and offline behaviors into a credit score through smartphone apps, creates a “new normal” way of life for Chinese citizens. This data-driven authoritarianism uses data and technology to enhance citizen surveillance. Interactions between individuals, technologies and information emerge from understanding the system as one that provides social goods, using technologies, and raising concerns of privacy, security and collectivity. An integrated critical perspective that incorporates the concepts of datafication and dataveillance enhances a general understanding of how data-driven authoritarianism develops through the social credit system.

This study builds upon an ongoing debate and an emerging body of literature on datafication, dataveillance and digital sociology while filling empirical gaps in the study of the global South. The Chinese social credit system has growing recognition and importance as both a governing tool and a part of everyday datafication and dataveillance processes. Thus, these phenomena necessitate discussion of its consequences for, and applications by, the Chinese state and businesses, as well as affected individuals’ efforts to adapt to the system.

This paper aims to study the anodization of aluminum in a mixture solution of 1,3-propanediol solutions and 0.4 mol l⁻¹ H₃PO₄ at a low temperature.

The morphology and composition of the resulting anodic aluminum oxide (AAO) template was characterized by means of a scanning electron microscope in combination with an energy dispersive spectrometer.

Pore density and pore diameter both were found to be dependent on the temperature of anodization.

The resulting AAO templates exhibited uniform and regular pores with diameters that were significantly smaller than those found in AAO templates anodized at room temperature.

This study aims to simultaneously enhance the load-carrying capacity and control the leakage rate of mechanical seals by optimizing the texture shape.

A multi-objective optimization approach is implemented to determine the optimal “free-form” textures and optimal circular dimples. Experiments are conducted to validate the simulation results.

The experimental coefficient of friction (COF) and leakage rate are in good agreement with the calculated results. In addition, the optimal “free-form” texture shows a lower COF and a lower leakage in most cases.

This work provides a method to optimize the surface texture for a better combination performance of mechanical seals.

The purpose of this paper is to examine how subnational institutions within a country explain the performance consequences of open innovation (OI) in emerging market enterprises (EMEs).

The paper conducts a regression analysis by using a novel panel data set comprising of 438 innovative Chinese firms over the period of 2008-2011.

The authors show that although on average openness to external actors improves innovation performance this effect is pronounced for EMEs that operate in subnational regions with a higher level of intellectual property rights (IPR) enforcement and of factor market development. The findings point to the context-dependent nature of OI strategy and the complementary effect of institutional parameters in emerging markets and help to reconcile the contrasting findings regarding the effect of OI in the prior literature.

This paper extends the literature on OI by suggesting that the analysis of the performance consequences of OI strategy should go beyond the nexus between OI and firm performance, and instead, focus on subnational-specific institutions, such as region-specific IPR enforcement, factor market development and intermediation market development, that may facilitate or constrain the effect of OI model.

The reform and opening-up of capital market is valued for promoting sustainable development, while its impact presented as the form of deregulation of short-selling on the green innovation of enterprises in developing countries remains unclear. The purpose of this study is to outline the significance of gradual reform of financial markets in developing countries for low-carbon transformation and provide implications for achieving carbon peaking and carbon neutrality goals.

Based on the green subdivided patent data and financial data of China’s A-share listed companies, this paper takes the implementation of securities margin trading program as a quasi-natural experiment and applies the difference-in-differences (DID) model to examine the impact of deregulation of short-selling constraints on the enterprises’ green transformation.

The findings reveal that the initiating securities margin trading program significantly enhances the green innovation performance of enterprises. These findings are valid after performing a series of robustness tests such as the parallel trend test, the placebo test and the methods to exclude other policy interference. Mechanism analyses demonstrate a two-faceted effect of the securities margin trading program on the green innovation of enterprises, in which short-selling policy increases the pressure on capital market deregulation and meanwhile induces the environmental protection investment. The heterogeneity results demonstrate that the impulsive effect imposed by securities margin trading program is more significant in experimental group samples with characteristics of lower financing constraints, belonging to heavy polluting industries and possessing better environmental supervision capability.

First, previous studies have focused on the impact of financial policies implemented by banking institutions on the green innovation of enterprises, but few literatures have explored the validity of relaxing short-selling restrictions or opening the capital market in the field of enterprise’s green transformation in developing country. From the view of securities market reform, this paper broadens the incentive and supervision effects of the relaxation of short-selling control on enterprise’s green innovation performance after the implementation of securities financing and securities lending policy in China’s capital market. Second, previous studies have explored the impact of command-and-control environmental regulations, as well as market-incentivized environmental regulations such as green finance, low-carbon pilots and environmental tax reform, on the green transition of enterprises. Recently the role of the securities market in the green development of enterprises has received more attention in academia. The pilot of margin financing and securities lending is essentially a market-incentivized regulatory tool, but there is few in-depth research on how it affects the green innovation of enterprises. This paper enriches the research on whether the market incentive financial regulation policy can contribute to the green transformation of enterprises under the Porter hypothesis. Third, some previous studies used the ordinary panel regression model to explore the impact of financial policy on enterprise’s innovation performance. However, due to the potential endogenous problems of the estimated model, it might get biased conclusions. Therefore, based on the method of quasi-natural experiment, this paper selects the margin trading pilot policy as an exogenous shock to solve the endogenous or reverse causality problem in traditional measurement model and applies the DID model to study the relationship between core indicator variables.

This study aims to obtain a design scheme of the surface texture on mechanical seal with lower friction and leakage by comparing two common texture types: dimples and grooves.

An optimal free-form shape and an optimal circular shape were chosen by multi-objective optimization, and two types of grooves with different directions were chosen by a series of experiments. Then, the optimal free-form dimple, the optimal circular dimple, the groove perpendicular to the direction of movement (hereafter called groove-1) and the groove angled at 60° to the direction of movement (hereafter called groove-2) were compared by experiments under different loads.

The optimal free-form dimple shows a better performance in terms of a lower coefficient of friction (COF) and a lower leakage than the other shapes, especially for the high speed and low load conditions. The reduction rate of COF is up to 37.5%, and the leakage rate is reduced by about 12.5%. The dimples have a lower leakage than the grooves. The groove angled at 60° to the direction of movement is easier to pump the oil into the interface of the sealing face, leading to a lower friction but a higher leakage.

This study provides a feasible surface texture design scheme for improving the combination performance of mechanical seals.

Disruptions at ports may destroy the planned ship schedules profoundly, which is an imperative operation problem that shipping companies need to overcome. This paper attempts to help shipping companies cope with port disruptions through recovery scheduling.

This paper studies the ship coping strategies for the port disruptions caused by severe weather. A novel mixed-integer nonlinear programming model is proposed to solve the ship schedule recovery problem (SSRP). A distributionally robust mean conditional value-at-risk (CVaR) optimization model was constructed to handle the SSRP with port disruption uncertainties, for which we derive tractable counterparts under the polyhedral ambiguity sets.

The results show that the size of ambiguity set, confidence level and risk-aversion parameter can significantly affect the optimal values, decision-makers should choose a reasonable parameter combination. Besides, sailing speed adjustment and handling rate adjustment are effective strategies in SSRP but may not be sufficient to recover the schedule; therefore, port skipping and swapping are necessary when multiple or longer disruptions occur at ports.

Since the port disruption is difficult to forecast, we attempt to take the uncertainties into account to achieve more meaningful results. To the best of our knowledge, there is barely a research study focusing on the uncertain port disruptions in the SSRP. Moreover, this is the first paper that applies distributionally robust optimization (DRO) to deal with uncertain port disruptions through the equivalent counterpart of DRO with polyhedral ambiguity set, in which a robust mean-CVaR optimization formulation is adopted as the objective function for a trade-off between the expected total costs and the risk.

The purpose of this paper is to simplify the computation of parameter estimation in the grey linear regression model and solve the problem that the development coefficient could not be computed in some sequence data, such as short‐term traffic flow.

Starting from the limitation that can be identified in the equation and analyzing the range using the method to estimate parameters, this paper researches the modelling mechanism and the other forms which are equivalent with the original form. At the same time, this paper gives an estimation method and gets the relationship in various forms and the relationship between the model and GM(1,1) model.

For the grey linear regression model, there exists a new method of parameter identification and three other forms as follows: the original form, the Whitenization equation and the connotation form.

The method of parameter identification exposed in the paper expanded the scope of the application of the grey linear regression model, and it can be used to model and forecast the urban road short‐time traffic flow.

This paper has solved some complicated problems such as the parameter estimation computation in the grey linear regression model. In addition, three kinds of representation forms of the model and its relationship between the model and GM(1,1) have also been presented. Finally, its application of the model in a short‐term traffic flow prediction has shown its superiority.

Abundance of cultural resources is a typical feature of traditional villages. It is particularly important to explore the development path of traditional villages from the perspective of cultural resources.

Based on symbiosis theory, establish a symbiotic development mechanism of traditional village characteristic cultural elements and use grey relation analysis (GRA) to evaluate the resource advantages of different cultural attributes. This paper proposes the traditional village development model of different symbiotic units in the county. An empirical study is conducted in conjunction with the national historical and cultural city of Xunxian County, Henan, China.

The results show that (1) according to the different attributes of humanistic cultural resources, artificial cultural resources and natural cultural resources in traditional villages, different symbiotic units can be divided, and advantageous resources can be shared through the symbiotic interface; (2) using GRA to calculate the grey relational degree between cultural resources sequence of different attributes and the sum of cultural resources sequence in the county and define as the active degree of humanistic culture, the inheritance degree of artificial culture and the integrity of natural cultural resources are shown to reflect the status of the inheritance of humanistic cultural resources, the existence of artificial cultural resources, and the protection of natural cultural resources; and (3) a comparative analysis of the active degree, inheritance, and integrity of each symbiotic unit leads to the proposal of three symbiotic models of folklore vitality, characteristic space, and natural ecology, all of which are beneficial to promote the formation of a symbiotic environment.

The main innovation of this paper is to put forward the research scale of symbiosis theory in the field of urban and rural planning at the county level, delimit the symbiosis units of traditional villages at the county level, complete the quantitatively evaluate cultural resources in different symbiotic units with GRA, revealing the symbiotic development mechanism of cultural resources characteristic elements in traditional villages.