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The purpose of this paper is to propose a quasi-three-dimensional (3D) thermohydrodynamic (THD) model for oil film bearings with non-Newtonian and temperature-viscosity effects. Its performance factors, including precision and time consumption, are investigated.

Two-dimensional (2D), 3D and quasi-3D numerical models are built. The thermal and mechanical behaviors of two types of oil film bearings are simulated. All the results are compared with solutions of commercial ANSYS CFX.

The 2D THD model fails to predict the temperature and pressure field. The results of the quasi-3D THD model coincide well with those of the 3D THD model and CFX at any condition. Compared with the 3D THD model, the quasi-3D THD model can greatly reduce the CPU time consumption, especially at a high rotational speed.

This quasi-3D THD model is proposed in this paper for the first time. Transient mechanical and thermal analyses of high-speed rotor-bearing system are widely conducted using the traditional 3D THD model; however, the process is very time-consuming. The quasi-3D THD model can be an excellent alternative with high precision and fast simulation speed.

In general, the existing compressor design methods require abundant knowledge and inspiration. The purpose of this study is to identify an intellectual design optimization method that enables a machine to learn how to design it.

The airfoil design process was solved using the reinforcement learning (RL) method. An intellectual method based on a modified deep deterministic policy gradient (DDPG) algorithm was implemented. The new method was applied to agents to learn the design policy under dynamic constraints. The agents explored the design space with the help of a surrogate model and airfoil parameterization.

The agents successfully learned to design the airfoils. The loss coefficients of a controlled diffusion airfoil improved by 1.25% and 3.23% in the two- and four-dimensional design spaces, respectively. The agents successfully learned to design under various constraints. Additionally, the modified DDPG method was compared with a genetic algorithm optimizer, verifying that the former was one to two orders of magnitude faster in policy searching. The NACA65 airfoil was redesigned to verify the generalization.

It is feasible to consider the compressor design as an RL problem. Trained agents can determine and record the design policy and adapt it to different initiations and dynamic constraints. More intelligence is demonstrated than when traditional optimization methods are used. This methodology represents a new, small step toward the intelligent design of compressors.

This paper aims to predict the 28-day compressive strength of recycled thermal insulation concrete more accurately.

The initial weights and thresholds of BP neural network are improved by genetic algorithm on MATLAB 2014 a platform.

Genetic algorithm–back propagation (GA-BP) neural network is more stable. The generalization performance of the complex is better.

The GA-BP neural network based on the training sample data can better realize the strength prediction of recycled aggregate thermal insulation concrete and reduce the complex orthogonal experimental process. GA-BP neural network is more stable. The generalization performance of the complex is better.

This study aimed to explore the spatial accessibility dynamics of urban parks and their driving forces from 1901 to 2010 in terms of the dynamic relationships between spatial morphology and road networks, taking Nanjing City as an example.

This study mapped and examined the spatiotemporal distribution of urban parks and road networks in four time points at Nanjing: the 1910s, 1930s, 1960s and 2010s, using the analysis methodology of spatial design network analysis, kernel density estimation and buffer analysis. Two approaches of spatial overlaying and data analysis were adopted to investigate the accessibility dynamics. The spatial overlaying compared the parks' layout and the road networks' core, subcore and noncore accessible areas; the data analysis clarified the average data on the city-wide and local scales of the road networks within the park buffer zone.

The analysis of the changing relationships between urban parks and the spatial morphology of road networks showed that the accessibility of urban parks has generally improved. This was influenced by six main factors: planning implementation, political policies, natural resources, historical heritage and cultural and economic levels.

The results provide a reference for achieving spatial equity, improving urban park accessibility and supporting sustainable urban park planning.

An increasing number of studies have explored the spatial accessibility of urban parks through the relationships between their spatial distribution and road networks. However, few studies have investigated the dynamic changes in accessibility over time. Discussing parks' accessibility over relatively long-time scales has practical, innovative and theoretical values; because it can reveal correlational laws and internal influences not apparent in short term and provide reference and implications for parks' spatial equity.

The purpose of this paper is to investigate the electrodeposition of copper coatings directly onto AZ31 magnesium alloy, considered as a substrate of electroplating nickel. The additive, pH, complexing agent, current density, time, and temperature of electrolytic bath were studied to understand electrodepositing copper coating on AZ31 magnesium alloy.

Electrodeposition of copper was carried out in an aqueous solution containing copper hydroxide, citrate, and fluorine ion, which avoids the replacement or corrosion of the magnesium alloy. The morphology, structure, and interface of the electrodeposited copper coating were investigated by a scanning electron microscope (SEM).

The copper coating was dense, and there was good adhesion of the copper coating on the AZ31 magnesium alloy. This suggests that successful deposition of copper using an electroplating process could decrease the cost of coating AZ31 magnesium alloy.

This paper will be helpful for the development of coating on magnesium alloy using electroplating processes.

Copper hydroxide and citrate were the main compositions of the electrolyte, combined with sodium poly dipropyl (SP) and polyethylene glycol (PEG) as brightening agents and can be used to electrodeposit copper directly onto AZ31 magnesium alloy.

Extant research on supply chain integration defines integration in different ways, and mainly discusses a limited number of integration elements. The purpose of this paper is to develop a conceptual integration model which consists of comprehensive elements that are important to academic research and industrial practices.

Key literature survey with drawing threads of existing practices together for developing a systematic referential model and then verify the model with a real case.

Developed a model consisting of integration elements residing at the strategic, managerial, operational, and fundamental levels (bottom line). Based on the benefit alignment, the total integration requires supply chain partners to integrate resource flows (material, information, knowledge, and finance), processes and organization, planning and control activities and strategy.

The research is based on secondary data and a case study illustration. Further empirical research is required.

The normative model can guide managers to integrate resources and activities in their efforts for an effective supply chain management. It supplements the Supply Chain Operations Reference Model developed by the Supply Chain Council with an interface description, which may guide the development of information systems for supply chain integration.

The comprehensive model provides a more inclusive and integrated perspective of supply chain integration. It is expected that the consensus of supply chain integration could be achievable based on this model. The conceptual framework will assist the researchers to determine integration variables of supply chain.

This study explores the influencing factors of smart supply chain innovation (SSCI) for going global companies and designs a theoretical framework.

This paper is a multi-case study that includes a combination of exploratory and explanatory case studies.

First, the authors find that SSCI is embodied in product development and supply chain empowerment, which represent exploitative innovation and explorative innovation, respectively. Meanwhile, supply chain empowerment has a positive impact on product development. Second, the going global policy affects the transformation of supply chain empowerment to SSCI practices. Third, in terms of exploitative innovation, personalized demand positively affects SSCI through product development. Finally, explorative innovation, including emerging technology application and supply chain ecologicalization, has a positive effect on supply chain empowerment and thereby affects SSCI.

Supply chain innovation in the context of a smart economy has gained great popularity. This study sheds light on the influencing factors and mechanisms of SSCI from the exploitative and explorative aspects of innovations.

Blockchain technology has been recognized as a potential solution to the challenges in managing healthcare information. Its adoption in the healthcare industry has garnered the attention of healthcare institutions and governments. Given the significant role of subsidies in promoting technology adoption, this study applies evolutionary game theory to examine the impact of government subsidies on the adoption of blockchain technology by healthcare institutions.

First, the authors analyze the interests of government administration departments and healthcare institutions separately in regards to blockchain adoption. Subsequently, the authors develop the payoff matrix of both participants and construct the evolutionary game model. And then, the authors calculate the replication dynamic equations and analyze the decision evolution of both participants through the replication dynamic equations and numerical experiments.

The numerical experiments demonstrate that government subsidies are effective in encouraging healthcare institutions to adopt blockchain technology. The study also reveals the necessary amount of subsidy required to guide healthcare institutions towards adoption. Additionally, the validity of the evolutionary game model in analyzing the interaction between governments and healthcare institutions is confirmed by the results.

Blockchain adoption in the healthcare industry differs from other emerging technologies, as there is the potential for it to reduce revenue for healthcare institutions. This study contributes to the analysis of theoretical models for promoting blockchain in the healthcare industry through subsidies. Additionally, it demonstrates the potential of evolutionary game theory in analyzing the adoption of blockchain technology, and the interaction between governments and healthcare institutions.

The purpose of the study is to examine the effects of “flipping the classroom” on student performance, evaluation, and attendance in managerial accounting principles.

The study uses a crossed within-participants research design (each student experiencing both traditional instruction and simplified flipped instruction) allowing for control of individual differences between students; repeated-measures regression analysis for overall effects; quantile regression for performance-segregated effects.

Flipping the classroom resulted in significant performance improvement, particularly for lower performing students. Course evaluations indicate a few instructor-related ratings were lower for the flipped approach. Attendance was lower under the flipped approach for initial class meetings where the instructional manipulation occurred.

The study design included a weak form of flipping. A stronger form of flipping with greater incentives for class preparation as well as lecture videos could have stronger results.

Flipping the classroom could be effective for application-oriented accounting courses, particularly for lower performing students.

This is one of very few studies on flipping providing evidence of effectiveness using a crossed within-participants research design.