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Assessments of urban green drainage infrastructure (UGDI) have always been a headache in contemporary times which is a roadblock to enticing investors. This study prioritized the underlying sustainability indicators of UGDI systems in Ghana. After an exhaustive literature review, some identified sustainability indicators were compounded into semi-structured questionnaires. Sixty-two built environment professionals were asked to rate the significance of each indicator. A parametric test was used to prioritize the indicators. The results indicated that the most significant underlying sustainability indicators were; 'Flood control', 'Compliance with sustainable development goals', 'multi-functionality', 'energy efficiency and GHG emissions' and 'Initial Construction Cost'. To understand how UGDI performs with regards to flood and pollution mitigation, specific geographical performance indicators are required. This is an under-explored area in the Ghanaian context. Hence, the indicators espoused in this study serve as a starting point for the development of appropriate frameworks to aid the implementation of UGDI. [ABSTRACT FROM AUTHOR]

Within some developing countries, wetlands have long been regarded as dumping grounds. However, there has been a gradual paradigm shift in societal attitudes towards recognising their importance as landscape features that provide benefits for humans and wildlife. Unfortunately, construction activities have continually plagued their existence. Therefore, this present research examines the risks factors associated with construction projects in wetlands ecosystem, using Ghana as a case study. A quantitative research strategy leaning towards the positivist paradigm was adopted. A structured survey was developed to collect data from key stakeholders. Purposive sampling was employed to recruit construction experts in the Kumasi Metropolis, with a total of 78 experts agreeing to participate. Relative Importance Index (RII), Mean Score Ranking and a One-Sample T-Test were used to analyse primary data collected. The findings revealed that the key driving forces spurring construction projects in wetlands were rapid urbanisation; high rate of migration; and scarcity of land for development. Critical risks factors associated with construction projects in wetlands were identified as cost overruns; exploitation of biological resources; and water pollution. Finally, the findings also showed that the most critical detrimental effects of construction projects in wetlands were the destruction of aquatic and terrestrial lives; loss of flood control capability; and deterioration of wetland water quality. The study recommends the protection and conservation of wetlands environments through systematized enactment and enforcement of environmental protection regulations by government and non-governmental institutions. This would ensure the preservation of important biodiversity and aid with pollution control and flood protection. [ABSTRACT FROM AUTHOR]

A theoretical and experimental study of a subwavelength lens that has one or two-dimensional layers of magnetic metamaterial elements is presented. Good subwavelength imaging can be achieved when a stop band in the vicinity of the resonant frequency appears in the dispersion characteristics and the imaging properties of the single and double lens are compared, indicating that the double lens has a superior performance.

The design and subsequent testing of two dimensional microstrip resonators fabricated from high-temperature superconducting TBCCO 2212 thin films deposited via radio frequency sputtering onto 50 mm diameter lanthanum-aluminum-oxide substrates are presented. The disk resonators, designed for operating in the persistent current switch and DCS1800 cellular bands, were shown to be superior to those manufactured from similar materials.