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This study aims to investigate the corrosion inhibition effect of extracted oil from Ziziphus lotus fruit on corrosion of C38 carbon steel in 5.5 M H₃PO₄ solution using potentiodynamic polarization and impedance techniques.

Oil composition was determined using gas chromatography, and the results showed that oleic and palmitic acids present approximately 84.0 per cent of its total chemical content. Electrochemical impedance spectroscopy (EIS) data were analyzed by adapting it to a well-developed electric circuit model. The inhibition efficiency of Z. lotus oil was calculated and compared using Tafel polarization and EIS.

Accordingly, the oil extract was found to act as an anodic type inhibitor. Furthermore, inhibition efficiency of Z. lotus oil extract increase with oil concentrations and achieve approximately 70.5 per cent at 3 g/L solution of Z. lotus oil.

The results obtained from different tested methods were in line, and the oil was able to reduce significantly the kinetics of the corrosion process of C38 carbon steel.

The purpose of this paper is to study the inhibition effect of (6-phenyl-3-oxopyridazin-2-yl) acetohydrazide (GP4) on the corrosion of mild steel in acidic medium by gravimetric measurements, potentiodynamic polarization, and electrochemical impedance spectroscopy (EIS).

Weight loss measurements, potentiodynamic tests and EIS were performed during this study.

(6-phenyl-3-oxopyridazin-2-yl) acetohydrazide (GP4) was found to be a very efficient inhibitor for mild steel in 1.0 M HCl solution, reaching about 85 per cent with inhibitor concentration 1.0 × 10-3 M at 303 K.

(6-phenyl-3-oxopyridazin-2-yl) acetohydrazide (GP4) was found to play an important role in the corrosion inhibition of mild steel in acidic solution.

This paper is intended to be added to the family of pyridazine derivatives which are highly efficient inhibitors and can be used in the area of corrosion prevention and control.

This study aims to conduct the aircraft electrical wiring interconnection system (EWIS) safety risk assessment process abundantly and hierarchically and establish the assessment index system considering the weights and interrelationships of different levels of indices.

Due to the failure of EWIS being multifactorial, hidden and diverse, this paper divides the factors influencing the failure of EWIS into 3 primary indices, 13 secondary indices and 38 tertiary indices. Taking open circuit failure (OCF) and short circuit failure (SCF) as examples, calculate the weights of assessment indices based on the triangular fuzzy number analytic hierarchy process (TFNAHP) and triangular fuzzy number decision-making trial and evaluation laboratory (TFNDEMATEL). The cloud model (CM) divides the risk levels and obtains the safety risk assessment results. The comparative analyses of different weight calculation methods, different failure modes and different aircraft EWIS zones verify the effectiveness and practicability of the proposed method.

The results show that the proposed method aligns more with the actual situation than other methods. Also, the results identify key focus objects in EWIS safety risk assessment, such as the surrounding environmental factors among the primary indices having the most significant influence on OCF and SCF, the risk level of SCF being higher than that of OCF, etc.

This paper proposes a safety risk assessment index system for aircraft EWIS based on the cable parameters, surrounding environmental factors, installation and protection methods. The weight assignment is added to the assessment index system, and the safety risk assessment model is constructed by combining TFNAHP, TFNDEMATEL and CM.

Claims and disputes are often unavoidable in the construction industry due to its unique and complex characteristics involving the massive investment of capital, lengthy project duration, and multiple project stakeholders. This chapter intends to identify the critical construction claims attributes, compare the perceptions of major stakeholders on different claim attributes, and investigate the contrast of the top five claim attributes between this study and previous ones. The literature review resulted in 48 claim attributes responsible for the construction project schedule delays. These attributes were then presented to Vietnam construction industry (VCI) practitioners in the form of a questionnaire survey. Data analysis was done based on the collected 113 qualified samples. Relative importance index (RII) was applied to determine the ranking of claim attributes. The results were that the top five causes of claims, that is, payment delays, mistakes by contractor during construction stage, delays in work progress by the contractor, financial failure of the contractor, and frequently changing requirements by the owner, lead to the schedule delays in VCI. These findings can assist the local industry practitioners and foreign companies seeking a share in the VCI market in understanding the causes of construction claims comprehensively and formulating the countermeasures to minimise their impacts and hence reduce the unnecessary losses and raise the likelihood of success as well as maintain sustainable relationships among stakeholders.

Total risk score (TRS) is considered one of the main indicators for risk evaluation. Several studies attempted to employ different types of risk indices for the evaluation of cost overrun causes. Hence, this study aims at performing a comparative analysis to evaluate the efficiency of three different approaches for TRS calculation.

Thirty-eight unique causes of cost overrun in urban-related construction projects were identified and a survey was conducted among construction professionals in Iran. The TRS for each cost overrun cause is calculated using single-attribute (SA), double-attribute (DA), and multiple-attribute (MA) approaches, and eventually, causes were ranked. Furthermore, principal component analysis (PCA), logistic regression analysis (LRA), and K-means clustering are utilized to compare the differences in the generated TRS using different approaches.

The results revealed that the TRS generated through the MA approach demonstrated the highest efficiency in terms of generating correlation between causes and their identified latent constructs, prediction capability, and classification of the influential causes in the same group.

The originality of this study primarily stems from the adoption of statistical approaches in the evaluation of the recently introduced TRS calculation approach in comparison to traditional ones. Additionally, this study proposed a modified application of the relative importance index (RII) for risk prioritization. The results from this study are expected to fulfill the gap in previous literature toward exploring the most efficient TRS calculation approach for those researchers and practitioners who seek to utilize them as a measure to identify the influential cost overrun causes.

The organic food market is one of the most promising in Europe, although national markets have developed at different rates. In Germany, organics' share of total food turnover is 2.7 per cent compared with 1 per cent in the UK. This study explores the reasons why the behaviour of consumers in the UK and Germany has been so divergent despite both groups of consumers holding similar attitudes about organic foods. This was done by investigating the underlying values driving food choice behaviour using means‐end theory and Laddermap 5.4 software. In both cases the dominant means‐end hierarchies were uncovered and the cognitive process mapped. Although similarities emerged with respect to values concerned with health, wellbeing and the enjoyment of life, product attributes sought in order to achieve these values were different between the groups. A major difference was found in the absence among the UK group of any connection between organic food and the environment.

This study aims to apply unit root test to investigate the behavior of Chinese firms toward their leverage policy. The study is based on two influential and competing theories of capital structure.

This study applies unit root test to investigate the behavior of Chinese firms toward their leverage policy. The study is based on two influential and competing theories of capital structure. Trade off theory advocates that firms have a target level of leverage ratio and that firms try to achieve that optimal leverage ratio, whereas pecking order theory argues that firms have no target level of leverage and that they follow a specific pattern of leverage. For this purpose, this study applies a Fisher type unit root test to 12,808 firm level observations. The data are unbalanced and cover a period from 1991 to 2014.

The results reveal the presence of a stationary behavior across short-term, long-term and total leverage policies. For short-term leverage policy, 21 per cent firms show stationary behavior, while for long-term, 20 per cent show a targeting behavior; for the total leverage policy 17 per cent of firms are found to follow a tradeoff model. To make the findings more interesting sample was further classified into profit and loss making firms. The study finds that loss making firms do not follow a target level of leverage in China. Furthermore, unit root is applied to all firms before and after crises-2008. It is revealed that stationary behavior is more prevalent before crises-2008.

This study is highly important from the point of view that it quantifies firms into distinct categories of following specific model of capital structure. To the best of the author’s knowledge, the findings of this study add to current research knowledge about Chinese firms with respect to adjustment behavior toward a target capital structure.

Over the last few years, the European Central Bank (ECB) has adopted unconventional monetary policies. These measures aim to boost economic growth and increase inflation through the bond market. The purpose of this paper is to study the impact of the ECB’s quantitative easing (QE) on the investor’s behavior in the stock market.

First, the authors theoretically identify the transmission channels of the QE shocks to the stock market. Then, the authors empirically assess the financial market’s responses to QE shocks in a data-rich environment using a factor augmented VAR (FAVAR).

The results show that the ECB’s unconventional monetary policy positively affects the stock market. A QE shock leads to an increase in stock prices and a drop in the realized volatility and the implied risk premium. The authors also suggest that the ECB’s QE is transmitted to the stock market through five main channels: the liquidity, the expectation, the portfolio reallocation, the interest rates and the risk premium channels.

The findings help to better understand the behavior of stock market assets in a data-rich economic context and guide investors and policymakers in the presence of unconventional monetary tools. For instance, decision-makers and investors should consider the short-term effect of the QE interventions and the changing behavior of the financial actors over time. In addition, high stock market returns can increase risk appetite. This can lead investors to underestimate the market risk. Decision-makers and market participants should take into consideration the impact of the large injection of money through the QE, which may raise the risk of a speculative bubble in the financial market.

To the best of the authors’ knowledge, this is the first study that incorporates a theoretical and empirical analysis to explore QE transmission to the stock market in the European context. Unlike previous studies, the authors use the shadow rate proposed by Wu and Xia (2017) to quantify the effect of the ECB’s QE in a data-rich environment. The authors also include two key risk indicators – the stock market risk premium and the realized volatility – to capture investors’ behavior in the stock market following QE shocks.

We develop a framework for measuring and monitoring business cycles in real time. Following a long tradition in macroeconometrics, inference is based on a variety of indicators of economic activity, treated as imperfect measures of an underlying index of business cycle conditions. We extend existing approaches by permitting for heterogenous lead–lag patterns of the various indicators along the business cycles. The framework is well suited for high-frequency monitoring of current economic conditions in real time – nowcasting – since inference can be conducted in the presence of mixed frequency data and irregular patterns of data availability. Our assessment of the underlying index of business cycle conditions is accurate and more timely than popular alternatives, including the Chicago Fed National Activity Index (CFNAI). A formal real-time forecasting evaluation shows that the framework produces well-calibrated probability nowcasts that resemble the consensus assessment of the Survey of Professional Forecasters.

Women’s empowerment is a multidimensional concept that encompasses different aspects such as access to education, freedom to make vital decisions, labor market access, wages, and political participation, among others. In this research, the authors construct a multidimensional index of women’s empowerment that takes into account individual resources and achievements and analyze its evolution across countries using data from the United Nations Development Programme and the United Nations for 17 gender indicators across 96 countries over the period 1995–2015. By means of exploratory and confirmatory factor analysis, the authors identify three dimensions of women’s empowerment: reproductive health, economic participation, and basic education. In addition, the authors use cluster techniques to classify countries into four groups with similar behavior patterns in the different domains of women’s empowerment: a group of countries with high levels in the domains of reproductive health and basic education but with low levels in economic participation; a group of countries with high levels in the domains of reproductive health and economic participation that should pay attention to education; a group of countries with medium levels across the three dimensions of women’s empowerment, especially in reproductive health and economic participation; and a group of countries with low levels in all the dimensions of women’s empowerment, especially in reproductive health and basic education. The comparison of these different patterns serves to highlight the aspects in which improvements have been made or, on the contrary, to highlight the obstacles that are hindering the improvement of gender equality. Finally, the results suggest that advancements in women’s empowerment improve the countries’ level of development.