Developing a leadership framework for improving construction business organisation performance in South Africa

The South African construction industry is experiencing challenging times, like its counterparts globally, which has led to the failure of known large contractors. While some studies have suggested different reasons for this, a stream of scholars argued that company leadership contributes significantly to the organisation's performance. Studies on leadership in construction have mainly been undertaken at project level, considering that construction organisations are project-based. This study examined the leadership of construction organisations and whether the traits, skills, role, style and strategic decisions of company leaders impacted on the long-term performance and sustainability of contracting firms in South Africa. The main question investigated in this study is: what combination of leadership traits, skills, style, role, and strategic decisions results in superior and sustainable construction organisation performance, when moderated by strategic decisions of CEO/company leadership? The study draws from theoretical perspectives, namely the ‘upper echelons' theory, strategic leadership theory, and the Full Range Leadership Model (FRLM), to develop a conceptual framework. A convergent mixed-method research design was used to advance the investigation. Fifteen semi-structured interviews were conducted with purposively selected construction company leaders of large contracting firms in the Western Cape, in positions of Group Chairman, Chief Executive Officer (CEO) or Managing Director in major building construction, civil engineering, or geo-technical companies of good repute. The survey instrument was pretested by construction company leaders before distribution to respondents and the Crobach Alpha test was used in testing the reliability of the study responses. The cidb provided the database of the construction leaders and a survey of contractors listed in Grades 7-9 of the cidb Register of Contractors was conducted. The responses of the samples on the survey question raised on their position also attests to this. At the end of the survey period between April and September 2020, 257 responses were received, representing 56.86% response rate. The data collected were analysed using descriptive and inferential statistics, including Structural Equation Modeling (SEM), to validate the hypothesis developed that construction company leaders positively impact organisational performance through their strategic decisions on project management, change, and innovation and investment. In addition, the study also tested the hypothesis that strategic decisions mediate the relationship between construction companies' leadership components, characteristics, and construction organisation performance. The findings of this study reveal that decisions on change and innovation have the most impact to prevent business failure, and for construction organisation performance. Whilst there are other internal and external factors that may contribute to a firm's business outcomes, the findings of the study explain that the attributes of construction business leaders and their strategic decisions play a significant role in construction company leadership and construction organisation's outcomes. The leadership of construction companies is expected to be exhibit transformational qualities, cast visions, channel new opportunities, and reposition their companies according to the current and future economic situations. The gap between expectations and performance must thus be filled by leadership through their strategic decisions that are premeditated and calculated towards the expectations and visions of the construction companies. The study thus contributes to knowledge in leadership and construction research by demonstrating how the multi-dimensions of company leadership impact construction business organisation performance. The integration of leadership personality traits, skills, style, role, and strategic decisions provides a better measure of how leadership impacts organisational performance. The leadership framework developed from the study's findings made explicit the leadership traits, skills, style and strategic roles that would assist construction company leaders to operate their organisations sustainably and devise effective succession plans. The components of the leadership framework include the strategic leadership roles that construction organisational leaders must play, using catalytic leadership skills, transformational and transactional leadership approaches and inherent leadership traits, which could be developed through education, career experiences, mentoring and training. The study is limited to South Africa, which has implications for the generalisability of results

Performance evaluation of in-building DAS for high data rate wireless transmission

In wireless systems, providing high data rate services is a major challenge, particularly for mobile terminals (MTs) in multi-floor buildings. The system performance is impaired by path loss, and co-channel interference due to the need to reuse the limited available spectrum. One way to achieve high data rates and better signal quality in this environment is by getting the transmitter and the receiver closer to each other through the use of distributed antenna systems (DASs). DAS reduces the overall transmit power (and hence co-channel interference) and achieves better link reliability by exploiting spatial diversity of multiple antennas. Currently, DASs are designed primarily to provide good coverage in outdoor environments. However, high quality indoor reception and high data rates may not be guaranteed if the system is not deployed within the building. Indoor environments can be very complex, and an insight into the design, and a thorough understanding of the performance of DASs inside the building is required. In this thesis, the performance of an in-building DAS employing frequency reuse is examined, where remote antenna units (RAUs) are deployed on each floor throughout the building and connected to a central unit (CU) where received signals are processea. The impact of co-channel interference on system performance is investigated by using a propagation channel model derived from multi-floor in-building path loss values retrieved from measurement results. System performance is investigated in terms of location-specific spectral efficiency and bit error rate (BER) which are analysed for a range of potential MT locations and various in-building propagation characteristics. The potential benefits of location based antenna selection and deployment options are also investigated. Co-channel interference cancellation where CUs cooperate through joint signal pro- cessing in order to reduce the impact of co-channel interference is considered. Results obtained suggest that the proposed scheme can facilitate better use of the available radio spectrum, and provide high data rates for indoor MTs

Performance Analysis of Small Cell and Distributed Antenna Systems for Indoor Mobile Communications

Fifth generation (5G) mobile communication systems aim to provide high data rate wireless transmissions and ubiquitous coverage to users but achieving this objective remains a challenge particularly in regions with high user density, such as urban/metropolitan areas and within buildings. To support users in indoor environments, indoor wireless communication systems are required, but frequency spectrum allocations are limited and requires reuse of the limited spectrum. Frequency reuse causes co-channel interference, which is detrimental to the performance and capacity of indoor systems. In order to design efficient and reliable indoor systems, a thorough understanding of co-channel interference within buildings is vital. This paper presents a comparative study of the performance of indoor deployed small cell base station (SBS) and indoor distributed antenna systems (DAS) in an isolated multi-storey building. Each floor of the building is equipped with either an indoor SBS or an indoor DAS where geographically distributed remote radio heads (RRHs) are connected to a central unit (CU), and frequency reuse is employed among floors. Signal propagation characteristics within multi-storey buildings and the impact of inter floor interference on system performance is analysed and compared for both systems. The effect of different reuse distances, pathloss exponents, penetration loss and co-channel interference on achievable rate is analysed over a wide range of potential mobile equipment (ME) locations

Optimizing the performance of the advanced encryption standard techniques for secured data transmission

Information security has emerged as a critical concern in data communications. The use of cryptographic methods is one approach for ensuring data security. A cryptography implementation often consists of complex algorithms that are used to secure the data. Several security techniques, including the Data Encryption Standard (DES), Triple Data Encryption Standard (3DES), Twofish, Rivest-Shamir-Adleman (RSA), Elliptic curve cryptography, and many others, have been created and are used in the data encryption process. However, the Advanced Encryption Standard (Rijndael) has received a lot of attention recently due to its effectiveness and level of security. To increase the scope of AES's numerous uses, it is crucial to develop high-performance AES. To enhance the processing time of AES methods, the research provided solution performance of the AES algorithm. This includes additional layers of encoding, decoding, shrinking and expansion techniques of the analysis that was performed. Data findings are produced for further actions based on the outcome

Fraud mitigation in attendance monitoring systems using dynamic QR code, geofencing and IMEI technologies

Attendance monitoring is a vital activity in several organizations. Due to its importance, many attendance monitoring systems have been developed to automate this process. Despite several advancements in automated attendance management solutions, attendance fraud remains an issue as some end users can manipulate known vulnerabilities, such as proxy attendance, buddy-punching, early departure, and so on. In this paper, a fraud-resistant attendance management solution is developed by harnessing technologies such as geofencing, dynamic QR code and IMEI Checking. The proposed solution is comprised of a single-page web application where QR code can be enabled for attendance registration, and a mobile application, where endusers can scan generated QR code to register their attendance. Attendance cheating via QR code sharing is prevented by encoding the polygonal coordinates of the event venue in the QR code to determine if the user is within the venue. The proposed system solves the problem of proxy attendance by registering and verifying the end user’s device IMEI number. Results obtained from testing indicate that attempts at committing a variety of attendance frauds are effectively mitigated

Heuristic antenna selection and precoding for a massive MIMO system

Sixth Generation (6G) transceivers are envisioned to feature massively large antenna arrays compared to its predecessor. This will result in even higher spectral efficiency (SE) and multiplexing gains. However, immense concerns remain about the energy efficiency (EE) of such transceivers. This work focuses on partially connected hybrid architectures, with the primary aim of enhancing the EE of the system. To achieve this objective, the study proposes a combined approach of joint antenna selection and precoding, which holds the potential to further optimize the system’s EE while maintaining a satisfactory SE performance levels. The proposed approach incorporates antenna selection based on a meta-heuristic cyclic binary particle swarm optimization algorithm along with successive interference cancellation-based precoding. The results indicate that the proposed solution, in terms of SE and EE, performs very close to the optimal exhaustive search algorithm. This study also investigates the trade-off between SE and EE in a low and high signal-to-noise ratio (SNR) regimes. The robustness of the proposed scheme is also demonstrated when the channel state information is imperfect. In conclusion, this work presents a lower complexity approach to enhance EE in 6G transceivers while maintaining SE performance and along with a reduction in power consumption

Isolation and Screening of Laccase-producing Fungi from Sawdust-contaminated Sites in Ado-Odo Ota, Ogun State, Nigeria

The environmental imbalance exerted by the continuous release of phenolic substances necessitates a return of polluted sites to natural and safe status. In this study, fungal isolates obtained from sawdust-contaminated soils were screened for laccase production capacities, using tannic acid, as an index to the bio-stimulatory potentials of the sawdust. Soil and sawdust samples collected from wood-processing plants in Morogbo-Agbara (M), Iju (I), and Oja (O) of Ado-Odo/Ota, Ogun State, Nigeria were subjected to physicochemical analysis. The phenolic content estimated using gallic acid calibration curve, showed 0.90%, 0.79% and 0.33% for the soil samples labeled MSL, ISL, OSL, respectively. Phenol content was observed to be 0.63%, 0.91%, and 0.53% for sawdust samples labeled MSD, ISD, OSD, respectively. In the same labeling order, the percentage nitrogen content was 0.77%, 0.38%, and 0.21% for soil; and 0.0025%, 0.0035% and 0.0028% for sawdust; while the percentage carbon was 0.25%, 0.62% and 0.49% for soil samples; and 88.11%, 85.56%, and 88.69% for the sawdust samples. Fungal species of Aspergillus, Penicillium, Candida and Saccharomyces among the ten isolates presented a positive reaction for laccase production by showing a brownish-black coloration. The ability of the fungal isolates to produce laccase makes them useful laccase sources for industrial and environmental application

Performance evaluation of in-building DAS for high data rate wireless transmission

In wireless systems, providing high data rate services is a major challenge, particularly for mobile terminals (MTs) in multi-floor buildings. The system performance is impaired by path loss, and co-channel interference due to the need to reuse the limited available spectrum. One way to achieve high data rates and better signal quality in this environment is by getting the transmitter and the receiver closer to each other through the use of distributed antenna systems (DASs). DAS reduces the overall transmit power (and hence co-channel interference) and achieves better link reliability by exploiting spatial diversity of multiple antennas. Currently, DASs are designed primarily to provide good coverage in outdoor environments. However, high quality indoor reception and high data rates may not be guaranteed if the system is not deployed within the building. Indoor environments can be very complex, and an insight into the design, and a thorough understanding of the performance of DASs inside the building is required. In this thesis, the performance of an in-building DAS employing frequency reuse is examined, where remote antenna units (RAUs) are deployed on each floor throughout the building and connected to a central unit (CU) where received signals are processea. The impact of co-channel interference on system performance is investigated by using a propagation channel model derived from multi-floor in-building path loss values retrieved from measurement results. System performance is investigated in terms of location-specific spectral efficiency and bit error rate (BER) which are analysed for a range of potential MT locations and various in-building propagation characteristics. The potential benefits of location based antenna selection and deployment options are also investigated. Co-channel interference cancellation where CUs cooperate through joint signal pro- cessing in order to reduce the impact of co-channel interference is considered. Results obtained suggest that the proposed scheme can facilitate better use of the available radio spectrum, and provide high data rates for indoor MTs.EThOS - Electronic Theses Online ServiceGBUnited Kingdo

Performance comparison of small cell and distributed antenna systems for in-building mobile communications

To bring fifth generation (5G) mobile communication capabilities to indoor users, small cells and distributed antenna systems are two promising technologies being considered. This paper investigates and compares the performance of indoor deployed small cell base station (SBS) and indoor distributed antenna systems (DAS) in an isolated multi-storey building. Each floor of the building is equipped with either an indoor SBS or an indoor DAS where geographically distributed remote radio heads (RRHs) are connected to a central unit (CU), and frequency reuse is employed among floors. Signal propagation characteristics within multi-storey buildings and the impact of inter floor interference on performance is analysed and compared for both systems. The effect of different reuse distances, pathloss exponents, penetration loss and co-channel interference on achievable rate is analysed over a wide range of potential mobile equipment (ME) locations

The impact of antenna selection and location on the performance of DAS in a multi-storey building

It is well known that providing high data rate wireless mobile services is a major challenge in indoor environments, particularly in multi-storey buildings. One way to achieve high data rate wireless transmissions is to reduce the radio transmission distance between the transmitter and the receiver by using distributed antenna systems (DASs) employing frequency reuse. However, due to the reuse of the limited available frequency spectrum, co-channel interference can severely degrade system performance. In this paper, the uplink performance of an in-building DAS with frequency reuse is studied, where remote antenna units (RAUs) deployed on each floor throughout the building are connected to a central unit (CU) where received signals are processed. The impact of RAU selection and location strategies on the performance of the interference-limited system is analysed by using a propagation channel model derived from multi-floor, in-building measurement results. The proposed scheme exploits the penetration loss of the signal through the floors, resulting in frequency reuse in spatially separated floors, which increases system spectral efficiency and also reduces co-channel interference. RAU location is shown to be a dominant factor influencing the levels of co-channel interference, and consequently, have a major implications on system performance