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This study aims to clarify the relationship between the coefficient of friction (COF) and temperature of aluminum-based brake discs.

Three friction blocks with different COFs are examined by a TM-I-type reduced-scale inertial braking dynamometer. On this basis, the thermo-mechanically coupled model of friction pairs is established to study the evolution of brake disc temperature under different COFs using ADINA software.

Results indicate that the calculated disc temperature field matches the experimental well. The effect of COF on the peak temperature is magnified by the braking speed. With the COF increasing, the rise rate of instantaneous peak temperature is accelerated, and the dynamic equilibrium period and cooling-down period are observed in advance. The increase in COF promotes the area ratio of the high-temperature zone and the maximum radial temperature difference. When the COF is increased from 0.245 to 0.359 and 0.434 at 140 km/h, the area ratio of high-temperature zone increases from 12% to 44% and 49% and the maximum radial temperature difference increases from 56°C to 75°C and 83°C. The sensitiveness of the axial temperature difference to the COF is related to the braking time. The maximum axial temperature difference increases with COF in the early stages of braking, while it is hardly sensitive to the COF in the later stages of braking.

The effect of COF on the aluminum-based brake disc temperature is revealed, providing a theoretical reference for the popularization of aluminum-based brake discs and the selection of matching brake pads.

This paper aims to study the use of electrochemical noise (EN) technology in the corrosion continuous monitoring of stainless steel (SS) in an atmospheric environment.

An EN electrode was designed and fabricated to acquire the EN of 304 SS in the atmospheric environment. The statistical analysis and shot noise analysis were used to analyze the EN, and the surface morphology analysis of 304 SS was used to verify the EN analysis results.

The activation state, passive film formation and pitting corrosion of 304 SS can be clearly distinguished by the amplitude and frequency change of EN. The metastable pitting corrosion and steady-state pitting corrosion can be identified with the shot noise parameters q and fn. Under the existence of chloride ion, the stability of 304 SS passive film decreases and the steady-state corrosion pits of 304 SS are more likely to form with the reduction of thin electronic layer (TEL) pH. The critical TEL pH of 304 SS corrosion is a pH between 3 and 4.

In an atmospheric environment, the EN technology was used in the corrosion continuous monitoring of SS.

Organic coatings are widely used for protecting metal equipment and structures from corrosion. Accurate detection and evaluation of the protective performance and service life of coatings are of great importance. This paper aims to review the research progress on performance evaluation and lifetime prediction of organic coatings.

First, the failure forms and aging testing methods of organic coatings are briefly introduced. Then, the technical status and the progress in the detection and evaluation of coating protective performance and the prediction of service life are mainly reviewed.

There are some key challenges and difficulties in this field, which are described in the end.

The progress is summarized from a variety of technical perspectives. Performance evaluation and lifetime prediction include both single-parameter and multi-parameter methods.

Global value chains (GVCs) have been challenged by several emerging macro-trends during the last years. Among them, sustainability of production and consumption patterns is becoming a central theme given the necessity to mitigate the degradation of the environment and the over-exploitation of scarce natural resources. In this respect, scholars and practitioners increasingly propose the circular economy (CE) approach as a systemic solution to overcome the conventional linear “take–make–use–dispose” model underlying the structure of contemporary global economy. However, the international business (IB) community has introduced the topic of CE only marginally in its debate. The aim of the present study is to fill this research gap identifying the opportunities for integrating IB and CE principles. Thus, the main objective is to investigate whether and how the adoption of the CE paradigm by multinational enterprises (MNEs) may affect activities, geographical configuration, and governance of their relevant GVCs.

The authors address the issue from a conceptual point of view, identifying direct and indirect impacts of CE adoption on GVC, relative enablers, and possible broader implications. Lastly, the authors propose some reflections for future investigations.

The purpose of this paper is to present a novel numerical algorithm, which can be used to simulate the stationary electric corona discharge in oxygen including some number of ionic species and ionic reactions.

Differential equations governing distribution of the electric field and space charge density for all ionic species have been solved using different numerical techniques: finite element method, method of characteristics (MoC) and donor‐cell method (DCM). Triangular discretization with linear interpolation of solution has been used.

Thickness of the ionisation layer in oxygen under normal conditions is in the order of a few hundred micrometers. Most electrons are attached to the neutral oxygen molecules forming negative ions in the drift zone. The current density on the ground plate basically follows the Warburg curve, but the DCM predicts a smooth current density distribution, while in the MoC the current density abruptly drops to zero at some radial distance.

This is the first attempt to solve this problem in the 2D point‐plane configuration. The results can lead to better understanding of all processes occurring in the corona discharge and provide information about density and distribution of different ionic species and current densities.

In this chapter, the epidemic diseases, their impact on the future of cities, and the causes of these problems for cities are examined. Additionally, efforts will be made to address these challenges and problems, a response that can make future cities livable and sustainable, despite population growth, increasing environmental problems, increasing urban management challenges, epidemic diseases and pandemics such as COVID-19 and other challenges and problems. This chapter will also discuss the steps taken in the field of smart transformation and smart cities and the necessity for cities to move toward smart transformation.

Artificial intelligence (AI) has quickly become a technology that serves public, commercial, and research purposes. By all expectations, AI will increasingly have a significant impact on the operations of international business. On December 13, 2019, the World Intellectual Property Organization (WIPO) invited member states and other multilateral institutions to contribute to the generation of guidelines that seek to regulate the application of AI within the intellectual property system. In this chapter, the authors discuss the possible effects of the upcoming WIPO regulation on international business.

Diabetes is a chronic metabolic disease that accounted for 6 per cent of total Indonesian deaths in 2016. The purpose of this study is to evaluate the ability of milk fermented using intestinal origin Lactobacillus casei strains to alleviate hyperglycemia in rats.

L. casei strains AP and AG were previously isolated and identified from feces of breastfed Indonesian infants (<1 month-old) and confirmed to be probiotics in vitro. These strains were used as bacterial starters to ferment milk, and the fermented product was fed to 25 diabetic rats for 15 days; metformin was used as a positive control. Blood glucose concentration, lipid profiles and total lactic acid bacteria counts were analyzed before and after treatment.

The results showed that feeding rats with milk fermented using L. casei strain AP decreased blood glucose concentration from 172.4 ± 2.1 to 147.2 ± 6.0 mg/dL (p < 0.05), whereas metformin reduced blood glucose concentration from 173.5 ± 6.5 to 124.2 ± 16.9 mg/dL (p < 0.05). Feeding milk fermented either L. casei AP or AG decreased low density lipoprotein but increased high density lipoprotein levels (p < 0.05).

This research finding is expected to increase the development of fermented dairy products as functional food, solutions for the prevention of hyperglycemia diseases which have a higher risk to occur on humans.

Further study is needed to examine the effect of L. casei AP-fermented milk on humans with hyperglycemia.

This research finding is expected to increase the development of fermented dairy products as functional food.

Oral administration of L. casei AP-fermented milk reduced hyperglycemia in rats similar to metformin. Further study is needed to examine the effect of L. casei AP-fermented milk on humans with hyperglycemia.

Informal associations are typical features of farm and non-farm ventures especially within rural communities. Owing to the informality of these associations, members of the groups usually evolve strategies to cope with different kinds of economic and social shocks such as the COVID-19 pandemic or unexpected economic recessions. Accordingly, entrepreneurship and non-farm business development in rural areas require massive finance input, which this group largely lacks owing to agrarian activities which is the main source of revenue. Therefore, to inform rural development policies, this chapter draws on the interrelationships that exist between finance options (including formal, informal and social networks) and small business development. Using the World Bank Living Standards Measurement Survey – Integrated Surveys on Agriculture (LSMS-ISA), the analytics identifies informal financing and social networks as leading alternatives to formal financing option in rural businesses. Therefore, we suggest that the government institutions recognise and formalise informal finance systems. This will not only aid access to government interventions and programmes, but foster collaborations with existing formal institutions and investors for sustainable rural business financing.

This chapter reports on a project undertaken during the author's two-term tenure as President of The World Council of Comparative Education Societies (WCCES) to document the history of this organization. The WCCES was founded at the First World Congress of Comparative Education, held in Ottawa, Canada in 1970. The author attended that First World Congress as a young academic and has subsequently attended five of the eleven World Congresses held to date. The two-volume Proceedings of the First World Congress of Comparative Education Societies was helpful in commencing this project.