SKILLED ARTISANAL AVAILABILITY IN THE GHANAIAN CONSTRUCTION INDUSTRY

The issue of skilled artisanal scarcity is not a current one. It dates as far back as the two world wars. This paper premised on the observation of the unavailability of skillful artisans in the Ghanaian Construction Industry (GCI). The objective of the study was to identify the factors aggravating the skilled artisanal scarcity in Ghana. Using relative important indices as the main statistical analysis tool, the following factors have been identified as the most important factors causing the scarcity situation : Irregular and low remuneration, low motivation, the lack of interest by the youth to take up trades like masonship and carpentry as professions, varying working conditions and technological advancements. The study recommends that an Association of Ghanaian Construction Artisans (AGCA) as a regulatory body to promote the welfare of its members i n other to address the issues raised by this study

The impact of the COVID-19 pandemic on deaf adults, children and their families in Ghana

This paper investigates the impact of the COVID-19 pandemic on deaf adults, children, and their families in Ghana, focusing on issues of inclusion. We ask what it takes to ‘make cities and human settlements inclusive, safe, resilient and sustainable’ (United Nations Strategic Development Goal 11) for deaf people in the context of the global pandemic in a low-resource context. The exceptional challenge to inclusion posed by COVID-19 is examined in terms of issues for deaf children and their families, and from the point of view of deaf adults in advocacy and support organisations. The pivotal language and communication issues are shown through a bioecological analysis that illuminates the interdependent dynamics of development and context, and their influence on access to, and understanding of, crucial information. It is argued that the global crisis of COVID-19 exposes and deepens issues of societal exclusion for deaf adults, children, and their families, and provokes wider questions about what inclusion means, and how it can be realised, in different cultural contexts

CO₂ Flux Field Delineation for Construction on Reclaimed Mine Land

The objectives of this work were to develop a soil CO₂ flux survey protocol for assessing reclaimed mine land for construction purposes and an approach to delineate high CO₂ flux fields for making decisions on post-mining land uses. The research involved CO₂ chamber accumulation flux surveys; stable carbon isotope ratio analysis; statistical techniques hypothesis testing to examine correlation between CO₂ flux and soil temperature and moisture as well as spatial dependence; and geostatistics to map CO₂ and delineate high flux zones. Soil temperature was observed to have a positive, monotonic correlation with fluxes while soil moisture was observed to have a negative, monotonic correlation. Spatial dependence of CO₂ fluxes on reclaimed mine land was observed on one of the two study sites. The research suggests that macro-porosity and gas permeability may be important factors that explain CO₂ migration in mine spoil. A flux survey protocol has been developed, based on these results, for reclaimed mine lands. The work demonstrates the capability of geostatistical methods to delineate high flux fields. Further research will be required to determine suitable thresholds for such analysis

Validierung des Tierstimmentests (mFAST)

Hintergrund: Die Ermittlung der frequenzspezifischen Hörschwelle mit Sinustönen (PTA) ist goldener Standard in der Audiometrie. Dennoch ist dieses Verfahren nicht ohne Probleme. Um mögliche Effekte der Feinstruktur der Hörschwelle zu reduzieren und alltagsrelevante Reize anzubieten, wird der Einsatz spektral komplexerer, breitbandigerer Stimuli postuliert. Besonders bei der Testung von jüngeren Kindern verspricht man sich dadurch Vorteile.Beim Tierstimmentest (mFAST: multi-Frequency Animal Sound Test) werden vier Tierstimmen (Kuh, Hund, Katze und Vogel) mit unterschiedlicher spektraler Zusammensetzung und mittlerer Frequenz (500, 1 k, 2 k, 4 kHz) verwendet, um die audiometrischen Hörschwellen in einem adaptiven Verfahren einzuschätzen.Material und Methoden: In einer ersten Validierung wurden die mFAST-Schwellen mit denen für äquivalente Rauschbänder und Reintöne verglichen (normalhörende Erwachsene). Zudem wurden die mFAST-Schwellen bei normalhörenden Kindern (4-6 Jahre) mit dem Tonaudiogramm (PTA) verglichen.Bei 45 normalhörenden Erwachsenen (89 Ohren, Alter: 20-30 J.) wurden die Hörschwellen mit dem AuriCheck® Handheld Audiometer gemessen. Neben mFAST wurde das duoTone Verfahren (Reintöne und Rauschbänder) eingesetzt, dem dasselbe adaptive Verfahren wie bei mFAST zugrunde liegt. 33 Kinder einer Kindertagesstätte (58 Ohren; 4-6 J.) wurden mit mFAST getestet, davon 28 Ohren zusätzlich spielaudiometrisch mit PTA.Ergebnisse: Bei den Erwachsenen zeigten sich keine signifikanten Unterschiede zwischen mFAST und duoTone bei Rauschen und Reintönen (mit Ausnahme von 7dB Unterschied bei 4 kHz Reintönen).Alle Kinder konnten mit mFAST getestet werden, während bei 20% eine Testung mit PTA nicht gelang. Die Hörschwellen waren altersabhängig und lagen bei mFAST durchschnittlich 6 dB über der PTA-Schwelle.Die Testdauer konnte mit einer kürzeren mFAST Version erheblich reduziert werden.Diskussion: Die Ergebnisse zeigen, dass mFAST als eine (bessere) Alternative zur Reintonaudiometrie bei Hörscreening und -testung jüngerer Kinder eingesetzt werden kann.Erste Ergebnisse der Validierung bei Hörgeschädigten werden präsentiert

High Performing HMA Design Optimization

The use of quality materials (aggregates and asphalt binder) in optimal proportions is the key to producing optimally performing hot mix asphalt (HMA). The Superpave mix design standard in the US introduced specific volumetric and binder property requirements in HMA design. Different methods for HMA constituent proportioning have been proposed in various guidelines. The design process to determine the HMA blend is currently iterative and engineers rely almost exclusively on experience. This approach is time consuming and often does not result in cost-optimal HMA mixtures. This paper introduces a mixed integer linear programming (MILP) optimization model for hot-mix asphalt constituent proportioning. The MILP model minimizes the total mix cost while satisfying all the volumetric, binder and mix property specification requirements. The model has been successfully validated with real-life example. The aggregates and binder ratios from the model were in close agreement with those from the contractor. The Bailey ratios and the gradation constraints were also satisfied. The cost of the optimal mix was $0.804/Mg less than that of the contractors\u27. This marginal reduction might make all the difference in an industry that is highly competitive. The MILP model also demonstrated that adding RAP to the contractor\u27s design would reduce the cost of the blend by$5.74/Mg. The virgin binder content was reduced by 1% because of the recycled asphalt contained in the RAP. This work represents the first successful attempt in incorporating both aggregate and asphalt performance requirements into the optimization formulation. Applying these models will ensure the minimum cost mix that meets all constraints and will increase profit margins for plant operators. Copyright © 2012 by SME

Energy Efficiency in Cable Shovel Operations

This chapter seeks to establish the current knowledge on energy efficiency of cable shovel operations. Additionally, the chapter uses a review of the literature to make recommendations for industrial best practices and for future research to address identified gaps in the literature. The chapter first presents the fundamentals of cable shovel operations and the factors that affect the energy efficiency of shovel operations. Subsequently, the chapter presents an overview of the latest research on cable shovel energy efficiency, which is used as the basis for the recommendations. The chapter recommends that industry practitioners should use the right drive systems for their cable shovels, use data analytics to understand shovel energy efficiency, and carefully evaluate the costs and benefits of energy efficiency initiatives. The chapter also recommends that future research on shovel energy efficiency should: (i) establish theoretical benchmarks for cable shovel operations; (ii) account for human factors in the design of operator guidance systems to assist operators during shovel operations; and (iii) evaluate how effective operator training programs are in improving shovel energy efficiency