Examining the awareness and usage of cyber physical systems for construction projects in Nigeria

Purpose In recent times, the construction industry is being influenced by technological innovations when delivering a better, more effective and efficient desired project, cyber-physical systems (CPSs) offer a coupling of the physical and engineered systems by monitoring, coordinating, controlling and integrating their operations. This study aims to examine the level of awareness of professionals and usage of CPSs for construction projects in Nigerian construction industry. Design/methodology/approach The target population for this study was the professionals in the construction industry consisting Architects, Quantity Surveyors, Engineers and Builders. Data collection was through the use of a structured questionnaire administered to the target population. The data was analyzed by using statistical tools. Findings This study concluded that the construction professionals in the Nigerian construction industry are mostly aware about the heating, ventilation and air conditioning (HVAC) systems, global positioning system, microphone, speakers and camera as the most widely used CPSs in construction industry. HVAC systems was also found to be the mostly adopted technologies in the construction industry. Originality/value This study recommended that platforms that increase the awareness and encourage the usage of CPSs in construction industry should be encouraged by stakeholders concerned with management of construction projects. Such include electronic construction and adoption of blockchain technology.

Finite-element modeling of partially prestressed concrete beams with unbonded tendon under monotonic loadings

Purpose The partially prestressed concrete beam with unbonded tendon is still an active field of research because of the difficulty in analyzing and understanding its behavior. The finite-element (FE) simulation of such beams using numerical software is very scarce in the literature and therefore this study is taken to demonstrate the modeling aspects of unbonded partially prestressed concrete (UPPSC) beams. This study aims to present the three-dimensional (3-D) nonlinear FE simulations of UPPSC beams subjected to monotonic static loadings using the numerical analysis package ANSYS. Design/methodology/approach The sensitivity study is carried out with three different mesh densities to obtain the optimum elements that reflect on the load–deflection behavior of numerical models, and the model with optimum element density is used further to model all the UPPSC beams in this study. Three half-symmetry FE model is constructed in ANSYS parametric design language domain with proper boundary conditions at the symmetry plane and support to achieve the same response as that of the full-scale experimental beam available in the literature. The linear and nonlinear material behavior of prestressing tendon and conventional steel reinforcements, concrete and anchorage and loading plates are modeled using link180, solid65 and solid185 elements, respectively. The Newton–Raphson iteration method is used to solve the nonlinear solution of the FE models. Findings The evolution of concrete cracking at critical loadings, yielding of nonprestressed steel reinforcements, stress increment in the prestressing tendon, stresses in concrete elements and the complete load–deflection behavior of the UPPSC beams are well predicted by the proposed FE model. The maximum discrepancy of ultimate moments and deflections of the validated FE models exhibit 13% and −5%, respectively, in comparison with the experimental results. Practical implications The FE analysis of UPPSC beams is done using ANSYS software, which is a versatile tool in contrast to the experimental testing to study the stress increments in the unbonded tendons and assess the complete nonlinear response of partially prestressed concrete beams. The validated numerical model and the techniques presented in this study can be readily used to explore the parametric analysis of UPPSC beams. Originality/value The developed model is capable of predicting the strength and nonlinear behavior of UPPSC beams with reasonable accuracy. The load–deflection plot captured by the FE model is corroborated with the experimental data existing in the literature and the FE results exhibit good agreement against the experimentally tested beams, which expresses the practicability of using FE analysis for the nonlinear response of UPPSC beams using ANSYS software.

Policy barriers to sustainable construction practice in the Nigerian construction industry: an exploratory factor analysis

Purpose Sustainable construction practice is structured on regulatory and non-regulatory policies in developed and most developing countries. With the gradual uptake of sustainability concerns in the construction industry, this paper aims to identify the strategic need for clear-cut policies to improve sustainable construction practice. Previous studies have harped on the need for regulatory and industrial/organisational policies on improving sustainable construction practice within the Nigerian construction industry. Design/methodology/approach A questionnaire survey was used to evaluate the perspectives of construction professionals on the policy barriers for sustainable construction practice in Nigeria, and 46 policy barriers were identified. A total of 249 questionnaires were returned and useable for analysis. Findings Factor analysis revealed four clusters in the policy barriers to sustainable construction practice in the following order of significance: implementation strategies for sustainable construction practice, owners/client inputs for sustainable construction practice, stakeholder’s policy barriers and governmental and regulatory policy barriers. Practical implications Mitigating the identified barriers through effective policies will require adequate inputs from all relevant policymaking stakeholders and ensure improved sustainable construction practice among stakeholders and policymakers in the industry. This will in turn set a high standard and promote the practice of sustainable construction. Originality/value This study goes a step further in identifying the policy issues needed to ensure a smooth implementation of sustainable construction practice. The research findings will serve as a guide for policymakers in developing countries that through mitigation of the identified barriers, sustainable construction practice will be promoted.

An investigation on the influence of sintering temperature on microstructural, physical and mechanical properties of Cu-SiC composites

Purpose The purpose of this study is to investigate the effect of the sintering temperature on the microstructural, mechanical and physical properties of Cu-SiC composites. Design/methodology/approach The powder metallurgy route was used to fabricate the samples. Cold compaction of powders was conducted at 250 MPa which was followed by sintering at 850°C–950°C at the interval of 50 °C in the open atmospheric furnace. SiC was used as a reinforcement and the volumetric fraction of the SiC was varied as 10%, 15% and 20%. The processed samples were metallurgically characterized by the scanning electron microscope (SEM). Mechanical characterization was done using tensile and Vickers’ micro-hardness testing to check the hardness and strength of the samples. Archimedes principle and Four-point collinear probe method were used to measure the density and electrical resistivity of the samples. Findings SEM micrograph reveals the uniform dispersion of the SiC particles in the Cu matrix element. The results revealed that the Hardness and tensile strength were improved due to the addition of SiC and were maximum for the samples sintered at 950 °C. The addition of SiC has also increased the electrical resistivity of the Cu-SiC composite and was lowest for Cu 100% while the relative density has shown the reverse trend. Further, it was found that the maximum hardness of 91.67 Hv and ultimate tensile strength of 312.93 MPa were found for Cu-20% SiC composite and the lowest electrical resistivity of 2.017 µ- Ω-cm was found for pure Cu sample sintered at 950 °C, and this temperature was concluded as the optimum sintering temperature. Research limitations/implications The powder metallurgy route for the fabrication of the composites is a challenging task as the trapping of oxygen cannot be controlled during the compaction process as well as during the sintering process. So, a more intensive study is required to overcome these kinds of limitations. Originality/value As of the author’s best knowledge, no work has been reported on the effect of sintering temperature on the properties of the Cu-SiC composites which has huge potential in the industries.

Secure energy aware routing protocol for IEEE 802.15.4 wireless sensor networks

Purpose The purpose of this paper is to investigate the latest research related to secure routing protocols in Wireless Sensor Network (WSN) and propose a new approach that can achieve a higher security level compared to the existing one. One of the main security issues in WSNs is the security of routing protocols. A typical WSN consists of a large number of small size, low-power, low-cost sensor devices. These devices are very resource-constrained and usually use cheap short-range radios to communicate with each other in an ad hoc fashion thus, achieving security in these networks is a big challenge, which is open for research. Design/methodology/approach The route updates and data messages of the protocol are authenticated using Edwards-curves Digital Signature Algorithm (EdDSA). Routing protocols play an essential role in WSNs, they ensure the delivery of the sensed data from the remote sensor nodes to back-end systems via a data sink. Routing protocols depend on route updates received from neighboring nodes to determine the best path to the sink. Manipulating these updates by inserting rouge nodes in the network that advertise false updates can lead to a catastrophic impact on the compromised WSN performance. Findings As a result, a new secure energy-aware routing protocol (SEARP) is proposed, which uses security enhanced clustering algorithm and EdDSA to authenticate route advertisements and messages. A secure clustering algorithm is also used as part of the proposed protocol to conserve energy, prolong network lifetime and counteract wormhole attacks. Originality/value In this paper, a SEARP is proposed to address network layer security attacks in WSNs. A secure clustering algorithm is also used as part of the proposed protocol to conserve energy, prolong network lifetime and counteract wormhole attacks. A simulation has been carried out using Sensoria Simulator and the performance evaluation has been discussed.

Radio frequency identification (RFID) stock control and geo-location data system from a moving vehicle

Purpose The purpose of the research has been the primary consideration and evaluation of a cost effective, reliable, robust and simple process of radio frequency identification (RFID)-based stock control, asset management and monitoring of concrete safety bollards used in the road environment. Likewise, the consideration of the use of the same system and technology to other items in and around the general road infrastructure. Design/methodology/approach The research approach undertaken has been an evaluation of the use of currently available RFID technology, with a key emphasis on low cost, ease of use, reliability and convenience. Practical field exercises completed in considering the relevant RFID tags and readers and associated software and apps and necessary software integration and development have been undertaken. At the same time, evaluating the specific limits created in the specific environment is being applied. Of particular interest has been the use of a moving scan in a vehicle drive-through or pass-bye, type reading system. This has been determined to be viable and completely practical, drastically reducing the key issue of time-taken. Practical application of the system from idea to real life application has been undertaken. The integration of the use of the RFID tag and reader system with necessary and related software to database upload and storage has been established. The creation of an online facility to allow the appropriate use of the data and to include the convenient output of an asset report has been undertaken. Findings The findings have provided the necessary insight confirming the use of RFID technology as a simple yet reliable, cost effective and adaptable stock control, asset management and geo-locating system in the road environment. The use of such systems in this particular environment is in its infancy, and is perhaps novel and original in the specific aspect of using the system to stock control, manage and monitor road safety concrete bollards and other roadside objects in the road environment. Originality/value To establish if in fact, stock control geo-locating can be reliably undertaken with the use of RFID tags and readers in the specific road and road construction environment, particularly with the use of moving RFID reading of passive tags. To establish the minimum requirements of a field usable RFID tag and reader, specifically applicable to the concrete safety bollards, however to other roadside furniture. To identify the minimum requirements of a function, simple app to minimise general requirements of the overall stock control and monitoring of the RFID-tagged objects. To establish the possibility of reading the tag data, global positioning system (GPS) location and video imaging footage as a single operation function. To determine the basic parameters or limits of the GPS geo-locating, on the proposed products selected and overall system. To determine the current best practice in respect of reasonable accuracy and detail in relation to price considerations to a fully function stock control and monitoring system. To identify the minimum requirements of an online database to receive, house and provide ongoing access to and report on the data. To identify the key differences and benefits between traditional stock control and monitoring systems, against that of proposed RFID tag, read and geo-locating system.

Role of cloud computing technology in the education sector

Purpose This paper aims to provide a literature review on the cloud-based platforms for the education sectors. The several aspects of cloud computing adoption in education, remote/distance learning and the application of cloud-based design and manufacturing (CBDM) have been studied and theorised. Design/methodology/approach A four-step methodology was adopted to analyse and categorise the papers obtained through various search engines. Out of 429 research articles, 72 papers were shortlisted for the detailed analysis. Findings Many factors that influence cloud computing technology adoption in the education sector have been identified in this paper. The research findings on several research items have been tabulated and discussed. Based on the theoretical research done on cloud computing for education, cloud computing for remote/distance learning and CBDM, cloud computing could enhance the educational systems in mainly developing countries and improve the scope for remote/distance learning. Research limitations/implications This study is limited to papers published only in the past decade from 2011 to 2020. Besides, this review was unable to include journal articles published in different languages. Nevertheless, for the effective teaching and learning process, this paper could help understand the importance and improve the process of adopting cloud computing concepts in educational universities and platforms. Originality/value This study is a novel one as a research review constituting cloud computing applications in education and extended for remote/distance learning and CBDM, which have not been studied in the existing knowledge base.

Evaluating the key risk factors in PPP-procured mass housing projects in Nigeria: a Delphi study of industry experts

Purpose The purpose of the study is to elicit risk factors that are peculiar to public-private partnership (PPP)-procured mass housing in Nigeria from the expert perspectives in ensuring the success of the scheme thereby reducing housing deficit in the country. Design/methodology/approach The risk inherent in construction projects had been established through literature in general. The risk in PPP projects is emerging because of the recent acceptance of the procurement option by governments all over the globe. The Nigerian Government has also adopted the procurement option in bridging the housing deficit in the country. This study, therefore, conducts a Delphi survey on the probability of risk occurrence peculiar to PPP mass housing projects (MHPs) in Nigeria. Pragmatic research approach through the mixed method of both quantitative and qualitative methods was adopted for this study. The quantitative method adopts the administration of questionnaires through the Delphi survey, whereas the qualitative method used interviews with the respondents. A two-stage Delphi questionnaire was administered to construction practitioners that cut across academics, the public and the private sectors by adopting convenient sampling techniques and following the Delphi principles and procedures. A total of 63 risk factors were submitted to the expert to rank on a Likert scale of 7 and any risk factors that the mean item score (MIS) falls below the grading scale of the five-point benchmark is deemed not necessary a risk factor associated with PPP MHPs and thereby expunged from the second round of the Delphi Survey. The interview was subsequently applied to the respondents to substantiate the risk factors that are peculiar to PPP-procured mass housing in the study area. Findings The findings show that risk factors such as maintenance frequent than expected, life of facility shorter than anticipated and maintenance cost higher than expected fall below 5.0 benchmark with MIS of 4.64 and 4.55 indicating that the risk factors are not peculiar to PPP mass housing in Nigeria. Research limitations/implications The implication for practise of this research is that these risk factors provide the PPP stakeholders with the comprehensive checklists that can aid in developing PPP risk assessment guidelines in the sector though both partners should be aware of the dynamic nature of risk because new ones might be emerging. Originality/value The authors hereby declare that the research findings are a product of a thorough research conducted in the study area and have not to be submitted or published by another person or publisher and due acknowledgement was made where necessary.

Fracture properties of GGBS-dolomite geopolymer concrete

Purpose This study aims to predict the fracture properties of geopolymer concrete, which is necessary for studying failure behaviour of concrete. Design/methodology/approach Geopolymers are new alternative binders for cement in which polymerization gives strength to concrete rather than through hydration. Geopolymer concrete was developed from industrial byproducts such as GGBS and dolomite. Present study estimates the fracture energy of GGBS geopolymer concrete using three point bending test (RILEM TC50-FMC) with different percentages of dolomite and compare with cement concrete having same strength. Findings The fracture properties such as peak load, critical stress intensity factor, fracture energy and characteristic length are found to be higher for GGBS-dolomite geopolymer concrete, when their proportion becomes 70:30. Originality/value To the best of the authors’ knowledge, this is an original experimental work.