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1 – 10 of 34Ebere Kalu, Chinwe Okoyeuzu, Angela Ukemenam and Augustine Ujunwa
We study the contemporaneous effects of US monetary policy normalization on African stock market using panel data from six African countries.
Abstract
Purpose
We study the contemporaneous effects of US monetary policy normalization on African stock market using panel data from six African countries.
Design/methodology/approach
Daily data from May 1, 2013 to December 31, 2018 were used in order to accommodate the announcement effects since the US monetary policy normalization announcement was made in May 2013, while the rate hike was in December 2015. The study used the FE, RE and PMG models.
Findings
The results revealed that US 10-year bond yield and Treasury bill rate shocks negatively affect stock prices in Africa. S$P500 shock positively affects African stock prices.The result revealed that the integration of African financial market to the global financial market is a major source of vulnerability. The finding that US Treasury bill rate is a major depressant of the African stock prices reveals the short-termism of foreign polio inflows into African economies.
Originality/value
We provide inexorably insight into the interplay of financial systems globally. It can be useful for the purposes of generalization in developing economies in the shape of African countries. More so, this study could be replicated in another economic bloc or region with the aim of further exposing the far-reaching spillover effects of the US monetary policy normalization.
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Jaeyoung Cha, Juyeol Yun and Ho-Yon Hwang
The purpose of this paper is to analyze and compare the performances of novel roadable personal air vehicle (PAV) concepts that meet established operational requirements with…
Abstract
Purpose
The purpose of this paper is to analyze and compare the performances of novel roadable personal air vehicle (PAV) concepts that meet established operational requirements with different types of engines.
Design/methodology/approach
The vehicle configuration was devised considering the dimensions and operational restrictions of the roads, runways and parking lots in South Korea. A folding wing design was adopted for road operations and parking. The propulsion designs considered herein use gasoline, diesel and hybrid architectures for longer-range missions. The sizing point of the roadable PAV that minimizes the wing area was selected, and the rate of climb, ground roll distance, cruise speed and service ceiling requirements were met. For various engine types and mission profiles, the performances of differently sized PAVs were compared with respect to the MTOW, wing area, wing span, thrust-to-weight ratio, wing loading, power-to-weight ratio, brake horsepower and fuel efficiency.
Findings
Unlike automobiles, the weight penalty of the hybrid system because of the additional electrical components reduced the fuel efficiency considerably. When the four engine types were compared, matching the total engine system weight, the internal combustion (IC) engine PAVs had better fuel efficiency rates than the hybrid powered PAVs. Finally, a gasoline-powered PAV configuration was selected as the final design because it had the lowest MTOW, despite its slightly worse fuel efficiency compared to that of the diesel-powered engine.
Research limitations/implications
Although an electric aircraft powered only by batteries most capitalizes on the operating cost, noise and emissions benefits of electric propulsion, it also is most hampered by range limitations. Air traffic integration or any safety, and noise issues were not accounted in this study.
Practical implications
Aircraft sizing is a critical aspect of a system-level study because it is a prerequisite for most design and analysis activities, including those related to the internal layout as well as cost and system effectiveness analyses. The results of this study can be implemented to design a PAV.
Social implications
This study can contribute to the establishment of innovative PAV concepts that can alleviate today’s transportation problems.
Originality/value
This study compared the sizing results of PAVs with hybrid engines with those having IC engines.
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The aim of the study is to provide a comprehensive understanding of interrelations of structural systems and main planning considerations in supertall buildings (≥300 m).
Abstract
Purpose
The aim of the study is to provide a comprehensive understanding of interrelations of structural systems and main planning considerations in supertall buildings (≥300 m).
Design/methodology/approach
Data were collected from 140 contemporary supertall towers using the case study method to analyze structural systems in the light of the key design considerations to contribute to the creation of more viable supertall building projects.
Findings
Central core typology, outriggered frame system, composite material and tapered prismatic and free forms were the most preferred features in supertall building design. Shear walled frame and tube systems occurred mostly in the 300–400 m height range, while outriggered frame systems were in the range of 300–600 m in height. Asia, the Middle East and North America mainly preferred outriggered frame systems, followed by tube systems. Considering the building function and form, the most preferred structural system in each of these groups was outriggered frame system, while mixed-use function stood out in all structural systems except in shear walled frame system.
Originality/value
To date, there has been no comprehensive study in the literature of the interrelations of structural systems and important planning considerations in the design of contemporary supertall towers through a large set of study samples. This critical issue was multidimensionally explored in this paper in light of 140 detailed case studies of supertall buildings around the world.
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Ehsan Sorooshnia, Maria Rashidi, Payam Rahnamayiezekavat, Fatemeh Rezaei and Bijan Samali
Optimisation of daylight admission through window is crucial for alleviating glare while maintaining useful daylight levels in order to enhance occupants' health, visual comfort…
Abstract
Purpose
Optimisation of daylight admission through window is crucial for alleviating glare while maintaining useful daylight levels in order to enhance occupants' health, visual comfort and moderating lighting energy consumption. Amongst various solutions, fixed external shade is an affordable solution for housing spaces that need to be sophisticatedly designed, especially during the period of increasing home spaces as working environments. In the humid subtropical region, daylight control plays an important role in indoor comfort, particularly with areas with a high window to wall ratio (WWR). Due to the insufficient amount of such study on non-office spaces in Australia, shading-related standards are not addressed in Australian building codes.
Design/methodology/approach
The chosen methodology for the research is a quantitative data collection and analysis through field measurement and simulation simultaneously. The first step is a multi-objective optimisation of shading elements through a non-dominated sorting genetic algorithm (NSGA-II) on parametric modelling via Rhino3D CAD and simulation engines (DIVA and ClimateStudio). In the second phase, the Pareto front solutions are validated by experimental measurements within a room with a single north-facing window (the most probable for the daytime glare in Sydney) for the seven most common local window configurations.
Findings
Through the simulation of ten genes, 1,560 values and 2.4 × 1,019 of search space, this study found an optimum shade for each local common window layout, resulted in +22% in (UDI) and −16% in views with discomfort glare on average. Moreover, an all-purpose polygonal shade showed an average of 4.6% increase in UDI and a 5.83% decrease in the percentage of views with discomfort glare.
Research limitations/implications
The findings are subject to the room dimensions, window dimensions and layouts, and orientation of windows for selected residential buildings in Sydney.
Originality/value
The study contributes to the development of highly accurate fixed external shading systems with rectangular and tapered-form external shapes. A real-time measurement by luminance-metre sensors and HQ cameras located at six eye levels is conducted to corroborate simulation results of the visual comfort.
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Zahra Salah Eldin, Mohamed Elsheemy and Raghda Ali Abdelrahman
Many countries around the world are facing great challenges from their ageing population with shrinking workforce, this will put more pressure on their financial system and will…
Abstract
Purpose
Many countries around the world are facing great challenges from their ageing population with shrinking workforce, this will put more pressure on their financial system and will increase the public spending on care costs provided to older people. Egypt is in the phase of establishing a new law for older people care's rights, a law that will organise how older people in need for care would benefit from access to government financial support and how will families support their older relatives financially and how the care costs will be shared between the older people, their families and the government.
Design/methodology/approach
The paper examines the suitability two cost-sharing methods and applying them to assess the effect on the individuals and families' income strain.
Findings
The preferred approach can be used for sharing costs as it applies a gradual funding withdrawal by the government and provide more fairness and flexibility for application in different regions. Besides, the parameters of this approach can be used by policy makers to control the levels of funding.
Originality/value
The paper will be the first to discuss the intergenerational fairness from a financial perspective in Egypt to avoid forcing older people into poverty or resorting to poverty trade-off.
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