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This paper aims to design an active shock absorber scheme for use in conjunction with a passive shock absorber to suppress the horizontal vibration of elevator cars in a smaller range and shorter time. The developed active shock absorber will also improve the safety and comfort of passengers driving in ultra-high-speed elevators.

A six-degree of freedom dynamic model is established according to the position and condition of the car. Then the active shock absorber and disturbance compensation-based adaptive control scheme are designed and simulated in MATLAB/Simulink. The results are analysed and compared with the traditional shock absorber.

The results show that, compared with traditional spring-based passive damping systems, the designed active shock absorber can reduce vibration displacement by 60%, peak acceleration by 50% and oscillation time by 2/3 and is more robust to different spring stiffness, damping coefficient and load.

The developed active shock absorber and its control algorithm can significantly reduce vibration amplitude and converged time. It can also adjust the damping strength according to the actual load of the elevator car, which is more suitable for high-speed elevators.

Motivated by the negative effect of external shocks on the domestic economy, this study explores the role of financial sector development in absorbing the effect of external shocks on macroeconomic volatility in Nigeria.

Autoregressive distributed lag and fully modify ordinary least square are used to examine the moderating effect of financial development in the link between external shocks and macroeconomic volatilities in Nigeria between 1986Q1 and 2019Q4. External shock is proxy using oil price shock, and financial development is proxy by domestic credit to the private sector and market capitalisation. At the same time, macroeconomic volatility is proxy by output and inflation volatilities. Macroeconomic volatilities are generated using generalised autoregressive conditional heteroskedasticity (GARCH 1,1).

The results indicate that domestic credit to the private sector significantly reduces output and inflation volatilities in Nigeria in the short and long run. However, market capitalisation promotes macroeconomic volatility. More specifically, financial development indicators play different roles in curtaining macroeconomic volatilities. The results also reveal that external shocks stimulate macroeconomic volatility in Nigeria in the short and long run. Nevertheless, the effects of external shocks on macroeconomic volatilities are reduced when the role of financial development is incorporated.

This study, therefore, concludes that strong financial sector development serves as a significant shock absorber in reducing the adverse effect of external shock on the domestic economy.

This study contributes to the extant studies by introducing a country-specific analysis into the empirical examination of how financial development can moderate the influence of external shock on macroeconomic volatilities.

The purpose of this paper is to explore and analyse the dynamic relationship between remittances inflows of Egyptians working abroad and asymmetric oil price shocks.

This study uses a vector autoregressive (VAR) model to explain the impulse response functions (IRFs) and the forecast error variance decomposition (FEVD). The rationale behind using these tools is its ability to examine the dynamic effects of our variables of interest.

The impulse response functions confirmed that remittance inflows have various responses to asymmetric oil price shocks. For instance, inflowing remittances increase in response to positive oil price shocks, while it decreases in response to negative oil price shocks. Also, the results indicate that the responses are significant in the short and medium-run and insignificant in the long run. The magnitude of these responses reaches its peak or trough in the third year. Further, the variance decomposition reveals that oil price decreases are more influential than oil price increases.

This means that remittances inflows in Egypt are pro-cyclical with oil price shocks. That explained by the fact that more than one-half of those remittances sent from GCC countries where real economic growth is very pro-cyclical with the oil prices. This empirical assessment will help policymakers to determine the behaviour of remittances and highlights the impact of different kinds of oil prices shocks on remittances. Unlike the little existing literature, this study is the first study applied the VAR model using a novel dataset spanning 1960-2016.

The Group of 20 (G20) is tasked with responding to economic shocks in the global financial system, with COVID-19 having proved to be the most significant shock since the G20's inception. COVID-19 also represents the first economic crisis accompanied by a concerted attempt to “build back better”, principally through a climate-compatible recovery. In 2021, there is little clarity as to the G20's response to this challenge, primarily due to considerable divergence in the green stimulus practices of its member states. The paper aims to investigate whether the G20, climate change and COVID-19 are critical juncture or critical wound.

Historical institutionalism (HI) suggests that one can explain an institution's future response by reference to its developmental pathway to date. This contribution adopts its concept of “critical junctures” to shed light on the G20's possible institutional response to COVID-19. The contribution undertakes a comparative analysis of the global financial crisis (GFC) and COVID-19 as possible critical junctures for the G20.

In doing so, the work demonstrates that the G20 “building back better” from COVID-19 requires a shift away from its institutional orthodoxy to a much larger degree than its response to the GFC. Accordingly, whilst both the GFC and COVID-19 may be considered critical junctures for the G20, only COVID-19 has the potential to be a “critical wound” that leads to institutional redundancy.

Through interrogating this further, this exposition prospectively outlines two possible futures the G20 faces as a consequence of COVID-19: reform or redundancy. In this way, it offers an ex ante perspective on policy-reform options for the G20's ongoing response to COVID-19.

Whichever choice the G20 makes in its response to COVID-19 has profound consequences for global governance in an increasingly unpredictable world.

Herein lies the importance of an exploratory assessment of COVID-19 as a critical juncture or a critical wound for the G20.