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This paper is supposed to provide a critical review of current research progress on thermal management in grinding of superalloys, and future directions and challenges. By understanding the current progress and identifying the developing directions, thermal management can be achieved in the grinding of superalloys to significantly improve the grinding quality and efficiency.

The relevant literature is collected from Web of Science, Scopus, CNKI, Google scholar, etc. A total of 185 literature is analyzed, and the findings in the literature are systematically summarized. In this case, the current development and future trends of thermal management in grinding of superalloys can be concluded.

The recent developments in grinding superalloys, demands, challenges and solutions are analyzed. The theoretical basis of thermal management in grinding, the grinding heat partition analysis, is also summarized. The novel methods and technologies for thermal management are developed and reviewed, i.e. new grinding technologies and parameter optimization, super abrasive grinding wheel technologies, improved lubrication, highly efficient coolant delivery and enhanced heat transfer by passive thermal devices. Finally, the future trends and challenges are identified.

Superalloys have excellent physical and mechanical properties, e.g. high thermal stability, and good high-temperature strength. The superalloys have been broadly applied in the aerospace, energy and automobile industries. Grinding is one of the most important precision machining technologies for superalloy parts. Owing to the mechanical and physical properties of superalloys, during grinding processes, forces are large and a massive heat is generated. Consequently, the improvement of grinding quality and efficiency is limited. It is important to conduct thermal management in the grinding of superalloys to decrease grinding forces and heat generation. The grinding heat is also dissipated in time by enhanced heat transfer methods. Therefore, it is necessary and valuable to holistically review the current situation of thermal management in grinding of superalloys and also provide the development trends and challenges.

This study aims to investigate the relationship between inventory flexibility, digital transformation, supply chain concentration, and productivity in the context of Chinese manufacturing enterprises.

Empirical analysis was conducted using data from listed Chinese manufacturing firms spanning from 2013 to 2022. The study employs a moderated model to examine how digital transformation influences the connection between inventory flexibility and productivity. Additionally, a moderated moderation model is utilized to explore the role of supply chain concentration in moderating the relationship among inventory flexibility, digital transformation, and productivity.

The study reveals a significant positive correlation between inventory flexibility and productivity, underlining the importance of flexible inventory management. Digital transformation moderates this relationship, with digital transformation enhancing the impact of inventory flexibility on productivity. Supplier and customer concentration also positively moderate this connection, suggesting a complementary relationship with digital transformation.

These findings offer valuable insights for managers and policymakers, emphasizing the need for a flexible approach to inventory management that considers the evolving digital landscape and supply chain dynamics.

This study contributes to the literature by providing empirical evidence of the nuanced relationship between inventory flexibility, digital transformation, supply chain concentration, and productivity in Chinese manufacturing enterprises. It underscores the importance of integrating digital transformation and supply chain concentration initiatives with flexible inventory management to optimize productivity in the business landscape.

There is growing empirical evidence that firm heterogeneity is technologically non-neutral. This chapter extends the Gandhi, Navarro, and Rivers (2020) proxy variable framework for structurally identifying production functions to a more general case when latent firm productivity is multi-dimensional, with both factor-neutral and (biased) factor-augmenting components. Unlike alternative methodologies, the proposed model can be identified under weaker data requirements, notably, without relying on the typically unavailable cross-sectional variation in input prices for instrumentation. When markets are perfectly competitive, point identification is achieved by leveraging the information contained in static optimality conditions, effectively adopting a system-of-equations approach. It is also shown how one can partially identify the non-neutral production technology in the traditional proxy variable framework when firms have market power.

The purposes of this paper are to investigate the biotribological behaviour of Vitamin E-blended highly cross-linked ultra-high molecular weight polyethylene (HXL-UHMWPE) under multi-directional motion by using a CUMT II artificial joint hip simulator and compare it with HXL-UHMWPE and conventional UHMWPE.

The biotribological behaviour of conventional, highly cross-linked and Vitamin E-blended highly cross-linked UHMWPE acetabular cups counterfaced with CoCrMo alloy femoral head under multi-directional motion were investigated by using CUMT-II artificial hip joint simulator for one-million walking cycles. The test environment was at 36.5 ± 0.5°C and 25 per cent bovine serum was used as lubricant. A Paul cycle load with a peak of 784 N was applied; the motion and loading were synchronized at 1 Hz.

The wear resistance of Vitamin E-blended highly cross-linked UHMWPE was significantly higher than that of highly cross-linked and conventional UHMWPE. The wear marks observed from the worn surface of UHMWPE were multi-directional, with no dominant wear direction. Only abrasion occurred on the surface of Vitamin E-blended highly cross-linked UHMWPE, while yielding and accumulated plastic flow processes occurred on the surface of conventional UHMWPE and flaking-like facture and abrasion occurred on the surface of highly cross-linked UHMWPE.

Besides the prevention of oxidative degradation, blending with Vitamin E can also reduce the incidence of fatigue crack occurred in the surface layer of HXL-UHMWPE samples. Therefore, the wear resistance of HXL-UHMWPE under multi-directional motion can be further enhanced by blending with Vitamin E.

The purpose of this paper is to examine the impacts of future climate change and the corresponding adaptation activities on grain production and its regional distribution in China.

This paper applied the Chinese Agricultural Policy Analysis model, in combination with the findings from agronomic literature with highly detailed agricultural census data, to conduct equilibrium analysis under alternative impact (seasonal drought and climate warming) scenarios and adaptation scenarios (promoting water-saving irrigation, introducing new varieties, and the integrated) associated with climate change.

Simulation results indicate that climate change-induced seasonal drought and the resulting yield reduction will incur substantial losses to China’s grain production (by ~8 percent at a national scale). The application of water saving techniques can be an effective solution to seasonal drought. Introducing new varieties will increase the combination of promoting water-saving irrigation and new variety adoption will increase combination of promoting water-saving irrigation and new variety adoption constitute an effective approach to offsetting the negative effects of climate change on grain production.

Simulation results indicate that climate change-induced seasonal drought and the resulting sown area reduction will incur substantial losses to China’s grain production by approximately 8 percent, despite farmers’ adaptation activities of switching from water use-intensive crops to drought-tolerant crops to mitigate this negative effect. The application of water saving techniques is an effective solution to seasonal drought; it can lead to a nationwide increase in the sown area by 3.48 percent and in the grain production by 4.15 percent. Introducing new varieties will increase grain outputs and change the spatial distribution of crop production across the country. The combination of promoting water-saving irrigation and new variety adoption will increase the national grain production by 19.6 percent, and thus constitute an effective approach to offsetting the negative effects of climate change on grain production.

Results from this study provide practical implications formulate strategies in response to climate change. Central government should reinforce the policies such as new varieties promotion and improve the subsidy method to guide the introduction of new varieties.

To discover the key elements of the use of the mechanism of public–private partnership for sustainable development, which are studied using the game approach.

Employed methods were as follows: trends method, regression analysis method, and game situation analysis method.

We discovered the key elements of the use of the mechanism of public–private partnership for sustainable development and determined the trends of the dependence of the sustainable development level on the mechanism of a public–private partnership at the level of countries that are leaders in this form of interaction (Denmark, Netherlands, Singapore, China, Switzerland and Finland). We reveal a positive dependence of the influence with China in 2017–2018 and with Finland in 2020–2021. The characteristics and strategies of implementing public–private partnerships are determined, and the spheres of influence of this form of interaction within the indicator of sustainable development are distinguished. We evaluate the perspectives of sustainable development under the influence of the public–private partnership mechanism. Based on the analysis results, it has been revealed that achievement of direct relation between the improved indicator of implementing the public–private partnership mechanisms and sustainable development could be realised within the orientation towards the effective strategic management of the interaction.

The scientific novelty of this research consists in the development of the theoretical and practical specifics of the use of the public–private partnership mechanism for sustainable development which determined using the game approach.

In this paper, the authors propose two construction methods to estimate confidence intervals of the time-based optimal software rejuvenation policy and its associated maximum system availability via a parametric bootstrap method. Through simulation experiments the authors investigate their asymptotic behaviors and statistical properties.

The present paper is the first challenge to derive the confidence intervals of the optimal software rejuvenation schedule, which maximizes the system availability in the sense of long run. In other words, the authors concern the statistical software fault management by employing an idea of process control in quality engineering and a parametric bootstrap.

As a remarkably different point from the existing work, the authors carefully take account of a special case where the two-sided confidence interval of the optimal software rejuvenation time does not exist due to that fact that the estimator distribution of the optimal software rejuvenation time is defective. Here the authors propose two useful construction methods of the two-sided confidence interval: conditional confidence interval and heuristic confidence interval.

Although the authors applied a simulation-based bootstrap confidence method in this paper, another re-sampling-based approach can be also applied to the same problem. In addition, the authors just focused on a parametric bootstrap, but a non-parametric bootstrap method can be also applied to the confidence interval estimation of the optimal software rejuvenation time interval, when the complete knowledge on the distribution form is not available.

The statistical software fault management techniques proposed in this paper are useful to control the system availability of operational software systems, by means of the control chart.

Through the online monitoring in operational software systems, it would be possible to estimate the optimal software rejuvenation time and its associated system availability, without applying any approximation. By implementing this function on application programming interface (API), it is possible to realize the low-cost fault-tolerance for software systems with aging.

In the past literature, almost all authors employed parametric and non-parametric inference techniques to estimate the optimal software rejuvenation time but just focused on the point estimation. This may often lead to the miss-judgment based on over-estimation or under-estimation under uncertainty. The authors overcome the problem by introducing the two-sided confidence interval approach.

Quality-Oriented Education (su zhi jiao yu) is a national education reform initiative that presents ongoing opportunities and challenges to schools, local bureaus of education, and the overall educational system in China today. This chapter seeks to gain insight into if and how Quality-Oriented Education, 10 years into its enactment, has taken root in practice. We posit that a reform agenda is best manifested through well-aligned and operable standards for school effectiveness. We introduce the policy-driven definition for school effectiveness and an evaluation framework depicting the intended focus of Quality-Oriented Education. Using an iterative and inductive process for content analysis, we compare the policy-driven framework with the coding results of a 2009 national inventory of actual school evaluation schemes in 91 Chinese school districts. Our review points out that the new mission of Quality-Oriented Education advocates educational equity, curriculum reform, and systemic support for school-based management. However, at the operational level, there are great variations in terms of content domain, focus, and function among school evaluation schemes with notable regional differences. Furthermore, schools are still caught between the existing system that measures school performance by achievement and the intended accountability scheme that calls for enhanced student ability. This chapter adds to the empirical foundation for the development of a new framework that not only captures the spirit of the national educational reform but also is informed of the developmental needs of schools in drastically different geo-economical and social conditions.

This research aims to improve the performance of rail fastener defect inspection method for multi railways, to effectively ensure the safety of railway operation.

Firstly, a fastener region location method based on online learning strategy was proposed, which can locate fastener regions according to the prior knowledge of track image and template matching method. Online learning strategy is used to update the template library dynamically, so that the method not only can locate fastener regions in the track images of multi railways, but also can automatically collect and annotate fastener samples. Secondly, a fastener defect recognition method based on deep convolutional neural network was proposed. The structure of recognition network was designed according to the smaller size and the relatively single content of the fastener region. The data augmentation method based on the sample random sorting strategy is adopted to reduce the impact of the imbalance of sample size on recognition performance.

Test verification of the proposed method is conducted based on the rail fastener datasets of multi railways. Specifically, fastener location module has achieved an average detection rate of 99.36%, and fastener defect recognition module has achieved an average precision of 96.82%.

The proposed method can accurately locate fastener regions and identify fastener defect in the track images of different railways, which has high reliability and strong adaptability to multi railways.

Today’s business environment has the nature that challenges the decision-making processes of businesses with its many different factors including technological developments and changing consumer structures. Previous research focused on specific contexts of the business environment regarding marketing and innovation issues, however, an integrative approach can be helpful for understanding and taking actions. This study aims to present a comprehensive framework which employs sensemaking from management literature as an approach to evaluate the market environment. Following a conceptual approach for the methodology, a framework consisting of three stages: discovery, sensemaking, and prediction is included in the study. Proposed framework identifies the stages for the sensemaking of consumers and can guide marketing decision-makers for competitiveness in the digital world.