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The purpose of this paper is to study the electrochemical, mechanical and thermal characteristics of polyester – epoxy coating systems using electrochemical impedance spectroscopy (EIS), pull-off test and differential scanning calorimetry (DSC). These are very important properties to evaluate the performance of a coating system. Proper measurement and analysis techniques are needed for a proper evaluation of these properties to ensure the coating performance.

Different ratios of polyester and epoxy resins have been blended to formulate good anticorrosive, mechanically strong and thermally stable binder coating system. EIS, pull-off test and DSC were used to evaluate these properties.

The sample containing 90 wt.% polyester exhibited the best corrosion resistance from the beginning until the end of exposure time. The value of corrosion resistance (R_c) obtained on the 30th day of exposure was found to be 2.89 × 108 ohm cm⁻². The glass transition temperature (T_g) was found to be increasing with the incorporation of epoxy to the binder system. The result from pull-off test showed the best adhesion with the sample containing 90 wt.% polyester which also has the lowest T_g promoted better adhesion properties.

The curing time must be reduced for practical applications.

Hybrid coatings systems have been formulated. This paper discusses on the highest coating resistance obtained polymer-substrate mechanical properties and thermal characteristic of the polyester/epoxy binder resin using DSC.

This paper aims to analyse the coating behaviour in corrosion environment as well as to evaluate the best percentage amount of copper oxide and copper needed for organic coating in order to prevent the corrosion degradation. Electrochemical impedance spectroscopy (EIS) studies have been conducted in order to evaluate the corrosion performance of polyester-epoxy-copper oxide and polyester-epoxy-copper coating systems.

The availability of this modem instruments is used to obtain impedance data as well as computer programs to interpret the results that made the technique popular. In addition, EIS is well suited to the study of polymer-coated metals.

The results showed that samples containing 25 weight per cent of copper oxide and copper (90P25CuO and 90P25Cu) obtained the excellent corrosion properties from the first day up to 30 days of NaCl immersion. The highest corrosion resistance values obtained by 90P25CuO and 90P25Cu on the 30th day were 7.107 × 108 O and 5.701 × 108 O, respectively, with lower double layer capacitance of 1.407 × 10⁻⁹ Farad and 3.935 × 10⁻⁹ Farad, respectively. Moreover, the water uptake gained by these two coating samples was the lowest at the end of immersion, which was 0.0084 for 90P25CuO and 0.1592 for 90P25Cu, showing that the sample has good corrosion performance.

This paper discussed on the highest corrosion resistance, double layer capacitance and the water uptake of the copper (Cu) and copper oxide (CuO) coating system obtained from the EIS measurements.

The purpose of this study is to investigate the relationship between digital competence and the capability to innovate in the service sector and examine if this relationship is mediated by human capital in the context of COVID-19 pandemic.

Using a cross-sectional survey, data were collected from 188 service sector professionals in the United Arab Emirates. Data were analyzed using partial least square-based structural equation modeling.

The findings of partial least square based structural equation modeling analysis indicate that there is a significant positive relationship between digital competence and the capacity to innovate in the service sector, which is partially mediated by human capital.

This study contributes to knowledge by offering an understanding of the relationship between digital competence and innovation capability, especially in uncertain situations. This study also notes the importance of human capital as a strategic resource for innovation.

Purpose – This chapter provides an overview of issues related to analysing crash data characterised by excess zero responses and/or long tails and how to overcome these problems. Factors affecting excess zeros and/or long tails are discussed, as well as how they can bias the results when traditional distributions or models are used. Recently introduced multi-parameter distributions and models developed specifically for such datasets are described. The chapter is intended to guide readers on how to properly analyse crash datasets with excess zeros and long or heavy tails.

Methodology – Key references from the literature are summarised and discussed, and two examples detailing how multi-parameter distributions and models compare with the negative binomial distribution and model are presented.

Findings – In the event that the characteristics of the crash dataset cannot be changed or modified, recently introduced multi-parameter distributions and models can be used efficiently to analyse datasets characterised by excess zero responses and/or long tails. They offer a simpler way to interpret the relationship between crashes and explanatory variables, while providing better statistical performance in terms of goodness-of-fit and predictive capabilities.

Research implications – Multi-parameter models are expected to become the next series of traditional distributions and models. The research on these models is still ongoing.

Practical implications – With the advancement of computing power and Bayesian simulation methods, multi-parameter models can now be easily coded and applied to analyse crash datasets characterised by excess zero responses and/or long tails.

This paper aims to numerically investigate the impact of gas diffusion layer (GDL) anisotropic transport properties on the overall and local performance of polymer electrolyte fuel cells (PEFCs).

A three-dimensional numerical model of a polymer electrolyte fuel cell with a single straight channel has been developed to investigate the sensitivity of the fuel cell performance to the GDL anisotropic transport properties – gas permeability, diffusivity, thermal conductivity and electrical conductivity. Realistic experimentally estimated GDL transport properties were incorporated into the developed PEFC model, and a parametric study was performed to show the effect of these properties on fuel cell performance and the distribution of the key variables of current density and oxygen concentration within the cathode GDL.

The results showed that the anisotropy of the GDL must be captured to avoid overestimation/underestimation of the performance of the modelled fuel cell. The results also showed that the fuel cell performance and the distributions of current density and oxygen mass fraction within the cathode GDL are highly sensitive to the through-plane electrical conductivity of the GDL and, to a lesser extent, the through-plane diffusivity, and the thermal conductivity of the GDL. The fuel cell performance is almost insensitive to the gas permeability of the GDL.

This study improves the understanding of the importance of the GDL anisotropy in the modelling of fuel cells and provides useful insights on improving the efficiency of the fuel cells.

Realistic experimentally estimated GDL transport properties have been incorporated into the PEFC model for the first time, allowing for more accurate prediction of the PEFC performance.

Purpose – This chapter overviews surrogate measures of safety to help better understand the related challenges and opportunities. The chapter is meant to serve as a primer for practitioners looking for alternative methods of evaluating safety where crashes are lacking or are insufficient.

Approach – The historical perspective and the current state-of-the-art thinking are presented in an organised manner with a focus on fundamental concepts, traffic measurement techniques and estimation of the relationships between surrogate events and collisions.

Findings – An analysis of the published research and its findings indicates that traffic conflicts are the most promising surrogates. They enable evaluation of the safety implications of a wide range of road and traffic conditions. The required ecological consistency between conflicts and collisions can be ensured by sufficient nearness of conflicts to collisions. Several methods of estimating the relationship between conflicts and crashes are discussed. Behavioural measures of safety are also discussed. Although easier to measure than conflicts, behavioural measures should be used with caution. Research on surrogate measures of safety may provide a basis for improving microsimulation models as tools of safety evaluation.

Practical implications – Current changes in vehicle and road instrumentation affect safety at a rate that exceeds the efficiency of the traditional crash-based methods of safety analysis. Accurate and quick measurement of safety with surrogate measures offers a viable solution. They are also a necessary condition of gaining a better understanding of safety and finding more effective solutions for safety problems.

This study aims to examine the linear and nonlinear remittance–institutional quality link in developing countries.

This study investigates the nonlinear relationship between remittance and political institutional quality in a panel of 97 developing countries using annual data of over nine years from 2009 to 2017. The estimated model uses system generalized method of moments for three political institutions indicators, namely, democracy, political stability and civil liberties.

The results revealed that remittance has a significant inverted U-shape impact on political institution’s indicators. Therefore, before the turning point, remittance is associated with high level of democracy, more stable political system and more civil freedom. While moving after the turning point indicates low level of political institution in the country.

The authors certify that this is the original paper. It has not been previously published and is not currently under submission or in press elsewhere.

Firms’ strategic responses to environmental shifts under conditions of uncertainty in the wake of institutional changes are far from understood. We utilize data from over 1,200 firms in seven Central Eurasian transition economies to examine the extent to which institutional inefficiency is predictive of the response strategies employed by the firms in their environments. We also examine how firms maneuver in the environment through an innovative effort in developing new products, opening new plants or upgrading product lines and technologies. Our results seem indicative of both an adaptive and an innovative effort by firms in these countries. The results are discussed with respect to empirical limitations and future research avenues in these transition economies.

The purpose of this study is to explore the roles of public–private partnership (PPP) leaders and the vital skills and competencies that PPP leaders should possess to ensure the success of PPP projects in Malaysia.

This study adopted an exploratory qualitative research design using an in-depth interview technique. Ten informants who were involved in the PPP projects from the public and the private sectors participated in this study. Data gathered from the in-depth interview were analysed using the constant comparative method.

The findings of this study show that among the main roles of PPP leaders are building a collaborative culture, leading and influencing the partnership process by developing trust and encouraging commitment and fairness. Key competencies were sensitivity of the cross-cultural issues between the public and the private sector, communication and PPP technical skills.

This paper outlines key competencies for the training and selection of PPP leaders and team members.

This paper enriches the existing body of knowledge on Malaysia’s PPP with regard to PPP leadership roles and their competencies.

Social entrepreneurship has played a significant role in reducing unemployment and poverty, fixing other social issues and environmental concerns. Although there is an increasing concern on social entrepreneurship by the public sector, practitioner and scholars, there are still limited studies on predicting the intention to become a social entrepreneur. Thus, investigating social entrepreneurship intention using a systematic literature review (SLR) approach is crucial due to the lack of systematisation and categorisation in this field. Therefore, this study aims to conduct a SLR to identify the antecedents of social entrepreneurial intention (SEI) used by the previous research. In this sense, this chapter carries out a systematic review of the literature on social entrepreneurship intentions. The review is guided by the PRISMA Statement (Preferred Reporting Items for Systematic reviews and Meta-Analyses). After the identification and screening process, only 56 articles were qualified for further analysis. This SLR focused on articles that are using quantitative research and in the English language published in Scopus. Although there is no limitation in the timeline, the search string results found that the related articles were published between 2010 and 2020. From the thematic analysis, nine main themes were found. The themes are categorised based on the antecedents of SEI used by previous research. There are nine antecedents found: (1) perceived desirability and feasibility, (2) attitude, subjective norms and perceived behavioural control, (3) prior experience, (4) emotional factors, (5) self-efficacy, (6) personality, (7) support systems, (8) skills and competencies and (9) motivational factors. Further analysis of the themes has resulted in ten sub-themes. This chapter's contribution includes offering a clearer picture of the antecedents of social entrepreneurial intention that is still at its infancy stage. Additionally, this chapter managed to identify the research gaps and proposed future research agenda.