Although the construction industry is a major player in the global economy, it is dealing with problems such as declining productivity, workplace safety, and work disputes. The human element—construction project managers in particular—is key to solving many of these persisting problems. A thorough understanding of construction project managers’ performance is important to identifying training needs, and enables executives to better match competent construction project managers with the appropriate projects. This paper examined competencies required for construction project managers and competency identification tools and techniques. Potentially relevant references were searched using appropriate search terms, topics, and publication dates in the ASCE Library. The process resulted in 2,102 references. Titles, abstracts, and contents of the references were examined further to select the most relevant references from the list; 31 of the initial 2,102 references were selected for content analysis. A systematic review and detailed content analysis of the 31 selected references from the ASCE Library published over the last 3 decades was conducted. Results of content analysis revealed that to identify competencies, two information gathering techniques predominantly were used in the selected sources, whereas three techniques seldom were used. A total of 39 competency categories required for construction project managers were identified. The most frequently identified competency categories were technical, leadership, communication, managing, organizing, and planning, teaming/teamwork, and determination. Findings of this study can assist the construction industry in directing its efforts toward key competency development areas and catering training and professional development to the real needs of the workforce.

Circular economy (CE) has attracted considerable attention from governments, policymakers, and societies due to its potential to promote sustainable development goals while shifting away from linear economy models. Despite a growing body of research conducted in the CE, the barriers to its successful implementation for solid waste management (SWM) remain less explored especially in context of municipal solid wastes, and commercial and industrial wastes. The purpose of this current study is to identify the critical barriers to circular economy implementation in SWM. The scientometric analysis of literature is the research methodology in this study. A total of 1709 journal articles were searched and retrieved from Scopus database for the data analysis. The results show that circular economy has not gained much root in solid waste management in the global south. Countries such as China, United States, Australia, Italy, and United Kingdom (UK) are the topmost countries to fund research in this research area. The commonly used keywords in scholarly literature on this topic include sustainability, reuse, waste management and recycle. Further, the major findings of the study were grouped into clusters relating to challenges on macroeconomic policies, recycling and reuse of waste, stakeholder management, operation, and legal regulations, generated solid wastewater treatment, and construction and demolition waste. The contributions of this research are twofold: a comprehensive list of relevant gaps for further studies are provided for the scientific community to delve into this matter and proffer solutions. The findings could serve as a guide to understand and develop best practice framework on circular economy and its implementation in the SWM.

Purpose: The application of circular economy (CE) has received wide coverage in the built environment, including public-private partnership (PPP) infrastructure projects, in recent times. However, current studies and practical implementation of CE are largely associated with construction demolition, waste and recycling management. Few studies exist on circular models and success factors of public infrastructures developed within the PPP contracts. Thus, the main objective of this article is to identify the models and key success factors associated with CE implementation in PPP infrastructure projects.Design/methodology/approach: A systematic review of the literature was undertaken in this study using forty-two (42) peer-reviewed journal articles from Scopus, Web of Science, Google Scholar and PubMed.Findings: The results show that environmental factors, sustainable economic growth, effective stakeholder management, sufficient funding, utilization of low-carbon materials, effective supply chain and procurement strategies facilitate the implementation of CE in PPP infrastructure projects. Key CE business models are centered around the extension of project life cycle value, circular inputs and recycling and reuse of projects.Research limitations/implications: Although the study presents relevant findings and gaps for further investigations, it has a limited sample size of 42 papers, which is expected to increase as CE gain more prominence in PPP infrastructure management in future.Practical implications: The findings are relevant for decision-making by PPP practitioners to attain the social, economic and environmental benefits of transitioning to circular infrastructure management.Originality/value: This study contributes to articulating the key models and measures toward sustainable CE in public infrastructure development.

Under emergencies such as floods and fires or during indoor navigation where cues from local landmarks and a Global Positioning System (GPS) are no longer available, the acquisition of comprehensive environmental representation becomes particularly important. Several studies demonstrated that individual differences in cognitive style might play an important role in creating a complete environmental representation and spatial navigation. However, this relationship between cognitive style and spatial navigation is not well researched. This study hypothesized that a specific type of map orientation (north-up vs. forward-up) might be more efficient for individuals with different cognitive styles. Forty participants were recruited to perform spatial tasks in a virtual maze environment to understand how cognitive style may relate to spatial navigation abilities, particularly the acquisition of survey and route knowledge. To measure survey knowledge, pointing direction tests and sketch map tests were employed, whereas, for route knowledge, the landmark sequencing test and route retracing test were employed. The results showed that both field-dependent and field-independent participants showed more accurate canonical organization in their sketch map task with a north-up map than with a forward-up map, with field-independent participants outperforming field-dependent participants in canonical organization scores. The map orientation did not influence the performance of Field-Independent participants on the pointing direct test, with field-dependent participants showing higher angular error with north-up maps. Regarding route knowledge, field-independent participants had more accurate responses in the landmark sequencing tests with a north-up map than with a forward-up map. On the other hand, field-dependent participants had higher accuracy in landmark sequencing tests in the forward-up map condition than in the north-up map condition. In the route retracing test, however, the map orientation had no statistically significant effect on different cognitive style groups. The results indicate that cognitive style may affect the relationship between map orientation and spatial knowledge acquisition.