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The purpose of this paper is to use Delphi technique to assess the applicability of coupling various project delivery methods (PDMs) and contract strategies (CSs) for delivery of public building projects (PBP) in Ethiopia.

To achieve the objective of this research, an online Delphi study was designed, conducted and analyzed using various statistical procedures. Results were compared to CII’s project delivery and CS (PDCS) tool, a US-based PDM selection tool.

This study converged in the third round signifying a consensus on the importance of design–build and construction manager at risk as alternatives to design–bid–build. In addition, “controlling schedule growth” was deemed to be a major performance measure that needs to be considered for PBP in Ethiopia, a result consistent with the outcomes from CII’s PDCS tool.

Among existing studies, none to the best of the authors’ knowledge has focused on a holistic approach to identify the most appropriate pairings of PDMs and CSs for PBP which was critically needed due to the magnitude and high stakes of these projects. This research is a steppingstone toward gaining knowledge on how to approach these types of projects in fast-growing environments thirsty for new building projects such as in Ethiopia.

Building information modeling (BIM) is a process of creating an intelligent virtual model integrating project data from design to construction and operation. BIM models enhance the process of communicating the progress of construction to stakeholders and facilitate integrated project delivery, coordination and clash detection. However, barriers within the construction industry in Ethiopia has led to slow BIM adoption in the country. The aim of this paper is to identify perceived BIM barriers, provide a platform to quantify their importance and develop a regression model to link individual's personal/professional attributes to their perception of BIM barrier.

To address the objectives of this research, an online survey was developed to collect feedback from construction professionals in Ethiopia on 20 major adoption barriers extracted from a thorough review of literature. Relative importance index and strength of consensus metric were employed to identify the significance of barriers. This was then succeeded by performing exploratory factor analysis to determine the major constructs of BIM barriers which was then used to develop a multivariate regression model linking respondents' personal attributes to their perception of BIM barrier.

Results revealed the importance of project complexity and BIM maturity level in prioritizing barriers that are more relevant under various contexts. More specifically, results indicated the following study highlights: Project complexity led to higher perceived weights for lack of appropriate physical/cloud infrastructures, and a BIM standard. Higher levels of BIM maturity signified the importance of BIM internal issues such as liability, licensing and maintenance issues among other adoption barriers. Female participants tended not to consider intangibility of BIM benefits as a major barrier towards BIM adoption compared to male participants. Age of the participants turned out to be the least important factor in their prioritization of BIM perceived adoption barriers.

While many research studies have explored BIM adoption barriers in various countries around the world, none to the best of the authors' knowledge have attempted to develop a model to highlight the impact of individuals' personal/professional attributes on their perception of adoption barriers within their community which can help with prioritizing the barriers that are deemed to be more important given the characteristics of the community under study. Our result indicated the importance of BIM maturity level and project complexity in prioritizing barriers associated with BIM adoption within Ethiopia's construction industry.

This study aims to carry out numerical modeling to predict aerodynamic noise radiation from four different Savonius rotor blade profile.

Incompressible unsteady reynolds-averaged navier-stokes (URANS) approach using gamma–theta turbulence model is conducted to obtain the time accurate turbulent flow field. The Ffowcs Williams and Hawkings (FW-H) acoustic analogy formulation is used for noise predictions at optimal tip speed ratio (TSR).

The mean torque and power coefficients are compared with the experimental data and acceptable agreement is observed. The total and Mono+Dipole noise graphs are presented. A discrete tonal component at low frequencies in all graphs is attributed to the blade passing frequency at the given TSR. According to the noise prediction results, Bach type rotor has the lowest level of noise emission. The effect of TSR on the noise level from the Bach rotor is investigated. A direct relation between angular velocity and the noise emission is found.

The savonius rotor is a type of vertical axis wind turbines suited for mounting in the vicinity of residential areas. Also, wind turbines wherein operation are efficient sources of tonal and broadband noises and affect the inhabitable environment adversely. Therefore, the acoustic pollution assessment is essential for the installation of wind turbines in residential areas.

This study aims to investigate the radiated noise level of four common Savonius rotor blade profiles, namely, Bach type, Benesh type, semi-elliptic and conventional. As stated above, numbers of studies exploit the URANS method coupled with the FW-H analogy to predict the aeroacoustics behavior of wind turbines. Therefore, this approach is chosen in this research to deal with the aeroacoustics and aerodynamic calculation of the flow field around the aforementioned Savonius blade profiles. The effect of optimal TSR on the emitted noise and the contribution of thickness, loading and quadrupole sources are of interest in this study.

The construction sector has significantly evolved in recent decades, in parallel with a huge increase in the amount of data generated and exchanged in any construction project. These data need to be managed in order to complete a successful project in terms of quality, cost and schedule in the the context of a safe project environment while appropriately organising many construction documents.

However, the origin of these data is very diverse, mainly due to the sector’s characteristics. Moreover, these data are affected by uncertainty, complexity and diversity due to the imprecise nature of the many factors involved in construction projects. As a result, construction project data are associated with large, irregular and scattered datasets.

The objective of this chapter is to introduce an approach based on a fuzzy multi-dimensional model and on line analytical processing (OLAP) operations in order to manage construction data and support the decision-making process based on previous experiences. On one hand, the proposal allows for the integration of data in a common repository which is accessible to users along the whole project’s life cycle. On the other hand, it allows for the establishment of more flexible structures for representing the data of the main tasks in the construction project management domain. The incorporation of this fuzzy framework allows for the management of imprecision in construction data and provides easy and intuitive access to users so that they can make more reliable decisions.

Life experience in hot and arid areas of Iran has proved that in the transitional seasons (spring and autumn) in which the climate is not too hot, passive cooling systems such as windcatchers (baadgir) have functioned well. This paper intends to investigate the efficiency of a single-side windcatcher as a passive cooling strategy; the case study is the Bina House windcatcher, located in Khousf town, near Birjand city, Iran.

To achieve the aim, air temperature, relative humidity, wind data and mean radiant temperature were measured by the related tools over five days from September 23 to October 23. Then, the thermal performance of the windcatcher was examined by analyzing the effects of all these factors on human thermal comfort. Quantitative assessment of the indoor environment was estimated using DesignBuilder and its computational fluid dynamics (CFD) tool, a thermal comfort simulation method to compare the cooling potential of the windcatcher. Windcatcher performance was then compared with two other common cooling systems in the area: single-side window, and evaporative cooler.

The results showed that both windcatcher and evaporative cooler can provide thermal comfort for Khousf residents in the transitional seasons; but the difference is that an evaporative cooler needs to consume water and electricity power, while a windcatcher is a passive cooling system that uses clean energy of wind.

The present study, by quantitative study of single-side windcatchers in a desert region, measured the climatic factors of a historical house and compared it with thermal comfort criteria. Therefore, the results of field measurements were analyzed, and the efficiency of the windcatcher was compared with two other cooling systems, namely single-side ventilation and evaporative cooler, in the two seasons of summer and autumn (transition seasons).

The purpose of this study is to extend the theory of planned behavior (TPB) and understand consumers' purchase intention of energy-efficient appliances (EEA) from the perspective of pro-environmental behavior. This study focuses on knowledge of eco-labels (KEL) and altruism for the consumers' purchase intention of EEA.

This study employed a quantitative method. Data of the participants were collected through the purposive sampling technique. A total of 373 valid responses were received with a response rate of 82.88%. Partial least square (SEM) has been used for the analysis of data.

The findings of the study reveal that altruism and KEL in the extended model of TPB promote the purchase of EEA in Pakistan. Further, the results indicate that altruism was the key predictor that leads to the consumption of environmentally friendly appliances.

Eco-labels are important sources that provide specific products related information to consumers. Further, eco-labeling serves to guide consumers' regarding the processes of products' consumption and disposals. Secondly, the positive influence of altruism implies the fact that people have the willingness to contribute to the betterment of the environment and human well-being. Therefore, marketers and policymakers should initiate campaigns that primarily target altruistic consumers and emphasize the importance of the purchase of EEAs that can reduce environmental pollution.

This study would help to understand consumer purchase intention for EEA and contribute to the literature of environmental management. The results of this study would serve to provide guidelines to policymakers and marketers regarding the consumption of environmentally friendly products (EFP).

Accessing adequate healthcare to all people is one of the main goals of the health sector. The purpose of this paper is to investigate healthcare services access development of the provinces in Iran during 2007 and 2013.

This is a descriptive cross-sectional study. The study population included all the provinces in Iran. The data for 13 variables, including physical and human health resources, was collected from the Ministry of Health and Medical Education and the Statistics Center of Iran. Taxonomy technique was used to determine the degree of healthcare services access development in the provinces.

The findings show that Semnan was the province with the most developed healthcare services access with development score of 0.342 while Sistan Balocehstan province was the least developed with development score of one in 2007. In the year 2013, Chahar-Mahal Bakhtiari and Sistan Baluchestan were the least and most developed provinces with scores of 0.551 and 0.989, respectively. The mean and standard deviation of the development scores in access to healthcare services in 2007 and 2013 were 0.7463±0.1268 and 0.7766±0.1058, respectively.

Most previous studies that examined disparities in access to healthcare resources in Iran only considered one resource. This study applied a taxonomy technique to investigate the disparity and changes in access using 13 main healthcare resources. This approach helped the authors to investigate whether the decisions of the policy makers were intended to eliminate the disparities.

Aim of the present monograph is the economic analysis of the role of MNEs regarding globalisation and digital economy and in parallel there is a reference and examination of some legal aspects concerning MNEs, cyberspace and e‐commerce as the means of expression of the digital economy. The whole effort of the author is focused on the examination of various aspects of MNEs and their impact upon globalisation and vice versa and how and if we are moving towards a global digital economy.