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This paper presents assessment results on the level of perceived knowledge in climate change and the extent to which participatory awareness in adaptation initiatives by management and the public in key selected areas identified to be highly impacted by climate change has fared.

Exploratory research design, using snowball, purposive and simple random sampling methods, was employed to assess respondents' level of knowledge in climate change and participatory adaptation awareness activities. Focus group discussion was finally used to appraise returned responses that compared indigenous knowledge with scientific data to examine variables influencing key determinants.

Age, gender, the level of education and work experience were all significant in determining outcome of responses by respondents on perceived level of knowledge in climate change and awareness in adaptation engagement efforts by the public. The study also confirmed existence of perceived knowledge and awareness gap with a marginal difference of 28% between management and stakeholder respondents.

Anthropogenic activities leading to climate change impacts are rarely linked to individual actions, lifestyles and community's sociocultural practices and choices.

There is a disconnect between what climate change managers know and are doing in terms of adaptation and mitigation efforts and what stakeholders should know and are expected to do toward achieving functional participatory engagements in Ghana. It calls for needs assessment on a governance system that will chart a new order to transform individual and household attitudes through curriculum development, awareness training, coping strategies to capacity building for members of the communities and households.

Environmental issues caused by the production of Portland cement have led to it being replaced by waste materials such as fly ash, which is more economical and safer for the environment. Also, fly ash is a material with sustainable properties. Therefore, this paper aims to focus on the development of sustainable construction materials using 100% high-calcium fly ash and potassium hydroxide (KOH)-based alkaline solution and study the engineering properties of the resulting fly ash-based geopolymer concrete. Laboratory tests were conducted to determine the mechanical properties of the geopolymer concrete such as compressive strength, flexural strength, curing time and slump. In phase I of the study, carbon nanotubes (CNTs) were added to determine their effect on the strength of the geopolymer mortar. The results derived from the experiments indicate that mortar and concrete made with 100% fly ash C require an alkaline solution to produce similar (comparable) strength characteristics as Portland cement concrete. However, it was determined that increasing the amount of KOH generates a considerable amount of heat causing the concrete to cure too quickly; therefore, it is notable to forming a proper bond was unable to form a stronger bond. This study also determined that the addition of CNTs to the mix makes the geopolymer concrete tougher than the traditional concrete without CNT.

Tests were conducted to determine properties of the geopolymer concrete such as compressive strength, flexural strength, curing time and slump. In Phase I of the study, CNTs were studied to determine their effect on the strength of the geopolymer mortar.

The results derived from the experiments indicate that mortar and concrete made with 100% fly ash C require an alkaline solution to produce the same strength characteristics as Portland cement concrete. However, it was determined that increasing the amount of KOH generates too much heat causing the concrete to cure too quickly; therefore, it is notable to forming a proper bond. This study also determined that the addition of CNTs to the mix makes the concrete tougher than concrete without CNT.

This study was conducted at the construction engineering and management concrete laboratory at North Dakota State University in Fargo, North Dakota. All the experiments were conducted and analyzed by the authors.

Challenges associated with ensuring the accuracy and reliability of cost estimation of highway construction bid items are of significant interest to state highway transportation agencies. Even with the existing research undertaken on the subject, the problem of inaccurate estimation of highway bid items still exists. This paper aims to assess the accuracy of the cost estimation methods employed in the selected studies to provide insights into how well they perform empirically. Additionally, this research seeks to identify, synthesize and assess the impact of the factors affecting highway unit prices because they affect the total cost of highway construction costs.

This paper systematically searched, selected and reviewed 105 papers from Scopus, Google Scholar, American Society of Civil Engineers (ASCE), Transportation Research Board (TRB) and Science Direct (SD) on conceptual cost estimation of highway bid items. This study used content and nonparametric statistical analyses to determine research trends, identify, categorize the factors influencing highway unit prices and assess the combined performance of conceptual cost prediction models.

Findings from the trend analysis showed that between 1983 and 2019 North America, Asia, Europe and the Middle East contributed the most to improving highway cost estimation research. Aggregating the quantitative results and weighting the findings using each study's sample size revealed that the average error between the actual and the estimated project costs of Monte-Carlo simulation models (5.49%) performed better compared to the Bayesian model (5.95%), support vector machines (6.03%), case-based reasoning (11.69%), artificial neural networks (12.62%) and regression models (13.96%). This paper identified 41 factors and was grouped into three categories, namely: (1) factors relating to project characteristics; (2) organizational factors and (3) estimate factors based on the common classification used in the selected papers. The mean ranking analysis showed that most of the selected papers used project-specific factors more when estimating highway construction bid items than the other factors.

This paper contributes to the body of knowledge by analyzing and comparing the performance of highway cost estimation models, identifying and categorizing a comprehensive list of cost drivers to stimulate future studies in improving highway construction cost estimates.

This paper aims to discuss the evaluation of the compressive and splitting tensile strength of concrete mixes containing different proportions of up to 20 per cent glass aggregate. Portions of sand in concretes with and without admixtures were replaced with measurements of glass aggregates.

“Glascrete” is a term used for concrete in which crushed glass is used as a substitute for all or part of the aggregates. Glass can be recycled many times without changing its properties, making it an ideal material in concrete. Overall, 144 cubes and 144 cylinders of glascretes were prepared with different admixtures and subjected to compressive and splitting tensile strength test.

A comparison with a 21-day control mix indicated that glass aggregates are replacing sand in concrete ranging from 5 to 20 per cent by volume, resulting in 3.8-10.6 per cent and 3.9-16.4 per cent fall in compressive and tensile strength, respectively. However, the use of mineral admixture improved the properties of the mixes at 3, 7, 14 and 21 days.

Cities worldwide are congested, and even those with the best waste-management system would have issues with waste disposal after the year 2030. Consequently, waste management is a current issue for cities all over the world.

This study aims to evaluate the physical properties of mortar mixes that contain different volumes of waste glass as substitutes for fine aggregate with or without additives. Mineral additives are used to improve the mechanical properties of glascrete mixes in addition to its chemical resistance by absorbing the OH⁻ ions responsible for the possible alkali-silica reaction (ASR). It also reduces the adverse effects of mix-dimensional stability. Water-reducing admixtures are used to reduce the impact of the ASR by minimizing the amount of moisture in concrete, in effect decreasing the possible expansion of any produced gel. In this research, compressive and splitting tensile strength of concrete mortar containing waste glass of limited substitutions is evaluated.

Background: Geostatistics focuses on spatial or spatiotemporal datasets. Geostatistics was initially developed to generate probability distribution predictions of ore grade in the mining industry; however, it has been successfully applied in diverse scientific disciplines. This technique includes univariate, multivariate, and simulations. Kriging geostatistical methods, simple, ordinary, and universal Kriging, are not multivariate models in the usual statistical function. Notwithstanding, simple, ordinary, and universal kriging techniques utilize random function models that include unlimited random variables while modeling one attribute. The coKriging technique is a multivariate estimation method that simultaneously models two or more attributes defined with the same domains as coregionalization.

Objective: This study investigates the impact of populations on traffic volumes as a variable. The additional variable determines the strength or accuracy obtained when data integration is adopted. In addition, this is to help improve the estimation of annual average daily traffic (AADT).

Methods procedures, process: The investigation adopts the coKriging technique with AADT data from 2009 to 2016 from Montana, Minnesota, and Washington as primary attributes and population as a controlling factor (second variable). CK is implemented for this study after reviewing the literature and work completed by comparing it with other geostatistical methods.

Results, observations, and conclusions: The Investigation employed two variables. The data integration methods employed in CK yield more reliable models because their strength is drawn from multiple variables. The cross-validation results of the model types explored with the CK technique successfully evaluate the interpolation technique's performance and help select optimal models for each state. The results from Montana and Minnesota models accurately represent the states' traffic and population density. The Washington model had a few exceptions. However, the secondary attribute helped yield an accurate interpretation. Consequently, the impact of tourism, shopping, recreation centers, and possible transiting patterns throughout the state is worth exploring.

The study seeks to examine women’s participation in Ghana’s extractive growth-driven economy and the quality of this participation in terms of employment status and earnings relative to their male counterparts and establish whether these differences constitute discrimination for policy attention.

The study adopts both quantitative and qualitative methodological approaches to assess the extent of gender inequality in employment and earnings in the Ghanaian extractive sector and the sources of these differences. It computes three segregation indices to ascertain the degree of unequal gender distribution of employment based on nationally representative labour force and living standards surveys followed by quantitative analysis of gender earnings differences using Oaxaca–Blinder decomposition technique. This is complemented by the results of Focus Group Discussion to go behind the numbers and examine the sources of the employment and earnings differences between men and women in extractive activities.

The authors observe lower participation of women in the extractive sector, with a considerable degree of gender segregation and existence of gender earnings gap in favour of men due to differences in observable characteristics such as age, education and occupational skills. There is also evidence of existence of discrimination against women and indication of barriers that impede women’s involvement in high-earning extractive activities in Ghana. The study suggests measures to remove these barriers and improve women’s education particularly in science, technology, engineering and mathematics to address the gender imbalance in extractive activities in Ghana.

Women’s low involvement in the strong extractive growth-driven process has implication for undermining the effort of empowering women economically.

The study draws argument from the literature and adopts a combination of quantitative and qualitative techniques to establish gender in terms of employment distribution and earnings in favour of males in the Ghanaian extractive sector. This has the effect of undermining women’s economic empowerment and exacerbating gender inequality in the country.

Background: The annual average daily traffic (AADT) data from road segments are critical for roadway projects, especially with the decision-making processes about operations, travel demand, safety-performance evaluation, and maintenance. Regular updates help to determine traffic patterns for decision-making. Unfortunately, the luxury of having permanent recorders on all road segments, especially low-volume roads, is virtually impossible. Consequently, insufficient AADT information is acquired for planning and new developments. A growing number of statistical, mathematical, and machine-learning algorithms have helped estimate AADT data values accurately, to some extent, at both sampled and unsampled locations on low-volume roadways. In some cases, roads with no representative AADT data are resolved with information from roadways with similar traffic patterns.

Methods: This study adopted an integrative approach with a combined systematic literature review (SLR) and meta-analysis (MA) to identify and to evaluate the performance, the sources of error, and possible advantages and disadvantages of the techniques utilized most for estimating AADT data. As a result, an SLR of various peer-reviewed articles and reports was completed to answer four research questions.

Results: The study showed that the most frequent techniques utilized to estimate AADT data on low-volume roadways were regression, artificial neural-network techniques, travel-demand models, the traditional factor approach, and spatial interpolation techniques. These AADT data-estimating methods' performance was subjected to meta-analysis. Three studies were completed: R squared, root means square error, and mean absolute percentage error. The meta-analysis results indicated a mixed summary effect: 1. all studies were equal; 2. all studies were not comparable. However, the integrated qualitative and quantitative approach indicated that spatial-interpolation (Kriging) methods outperformed the others.

Conclusions: Spatial-interpolation methods may be selected over others to generate accurate AADT data by practitioners at all levels for decision making. Besides, the resulting cross-validation statistics give statistics like the other methods' performance measures.

Concrete is a building material widely used for the infrastructural development. Cement is the binding material used for the development of concrete. It is the primary cause of CO₂ emission globally. The purpose of this study is to develop sustainable concrete material to satisfy the present need of construction sector. Geopolymer concrete (GPC) is a sustainable concrete developed without the use of cement. Therefore, investigations are being conducted to replace the cement by 100% with high calcium fly ash (FA) as binding material.

High calcium FA is used as cementitious binder, sodium hydroxide (NaOH) and sodium silicates (Na₂SiO₃) are used as alkaline liquids for developing the GPC. Mix proportions with different NaOH molarities of 4, 6, 8 and 10 M are considered to attain the appropriate mix. The method of curing adopted is ambient and oven curing. Workability, compressive strength and microstructure characteristics of GPC are analysed and presented.

An increase of NaOH in the mix decreases the workability. Compressive strength of 29 MPa is obtained for Mix-I with 8 M under ambient curing. A polynomial relationship is obtained to predict the compressive strength of GPC. Scanning electron microscope analysis is used to confirm the geo-polymerisation process in the microstructure of concrete.

This research work focuses on finding some alternative cementitious material for concrete that can replace ordinary portland cement (OPC) to overcome the CO₂ emission owing to the utilisation of cement in the construction industry. An attempt has been made to use the waste material (high calcium FA) from thermal power plant for the production of GPC. GPC concrete is the novel building material and alternative to conventional concrete. It is the ecofriendly product contributing towards the improvement of the circular economy in the construction industry. There are several factors that affect the property of GPC such as type of binder material, molarity of activator solution and curing condition. The novelty of this work lies in the approach of using locally available high calcium FA along with manufactured sand for the development of GPC. As this approach is rarely investigated, to prove the attainment of compressive strength of GPC with high calcium FA, an attempt has been made during the present investigation. Other influencing parameter which affects the strength gain has also been analysed in this paper.

The advances in green city growth are widely discussed in extant literature. The benefits of green cities to urban development in recent discussions of sustainability and sustainable development are well documented and cannot be overemphasised. Although a growing study on green building development in developing countries has been advanced in literature, there is a paucity of studies that explore green cities in developing countries. Moreover, evidence of studies that have focussed on green cities development in Ghana is lacking. Because of this identified knowledge gap, the purpose of this study is to establish the indicators/attributes for measuring the level of greenness of cities in developing countries.

A comprehensive literature review was conducted to identify the indicators/attributes for measuring the level of greenness of cities in developing countries. This study has adopted the pragmatism as its undergirding research philosophy and the deductive research approach. In terms of methodological choice, quantitative research strategy was used to collect data from experts in sustainable urban development. The primary data retrieved from this study was analysed using descriptive statistics, relative importance index and one-sample t-test. The reliability and validity of this study were measured with the Cronbach’s alpha test.

This study established eight indicators for measuring green city development: air quality, water, sanitation, land use, health and safety, transportation, energy and building and construction. It was discovered that the development of green cities should enhance air quality, improve water production and supply, improve management in sanitation, promote mixed and integrative land use, maintain the health and safety of city dwellers, reduce the demand for transportation and formalise public transport, adopt renewable and efficient energy technologies and promote sustainable construction and green buildings. These indicators are key to policymaking and implementation of green cities development.

This study focusses primarily on Ghana; however, the findings of this study do not limit the generalisability, as it can be used as an example for other developing countries.

Theoretically, this study adopted quantitative indicators that are reproducible in another geographical context. This study contributively adds to the discourse on sustainability, especially in Ghana, and can be a source of reference to motivate others to conduct further research in related areas. The outcomes of this study will help the local government, policymakers, city stakeholders and industry expertise to gain insights of the overall indicators that underpin green city development.

This paper attempts to posit in literature the foremost appraisal of green city indicators adaptive in Ghana, which could motivate other developing countries to develop their own green cities.