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Infrastructure deficiency and supply disruption challenges are quite common among developing economies. While Sub-Saharan Africa is not unique to these challenges, it is the extent of levels of infrastructure deficiency and disruptions that affect the level of performance of small businesses. Literature on the performance of small businesses suggests both infrastructure availability and disruptions affect the performance of small businesses, but the effects on informal enterprises that operate from locations where the supply of infrastructure is weak are less documented. The paper, therefore, investigates the effects of four types of infrastructure supply in two dimensions of availability and disruption levels on the performance of informal enterprises in 12 Sub-Saharan African countries.

The study uses data from World Bank informal enterprises surveys based on a sample of 3 735 informal enterprises. The study uses the multiple analysis of variance method based on the World Bank's Informal Enterprise Surveys (IFS) country-level cross-sectional data collected between 2009 and 2019.

Results show infrastructure supply is quite low irrespective of the form of infrastructure. Infrastructure availability is associated with high supply disruptions. Infrastructure supply deficiency and disruption intensities are negatively associated with informal enterprises' performance. Finally, the effects of both infrastructure availability and supply disruptions are positively associated with informal enterprises' business activity levels.

Due to data limitations, only four types of infrastructure are captured in the analysis. A wider variety of types of infrastructure could improve the analysis.

Given the deficiency level of infrastructure and its implications on informal enterprise development, therefore, policy interventions aiming at addressing informal enterprises' challenges should focus on improving infrastructure supply deficiencies and disruption challenges. This paper provides the link between infrastructure levels, infrastructure supply disruptions and performance of the informal enterprises which is an essential starting point for policy intervention in informal enterprise development.

This study aims to evaluate the key risk factors inherent in public–private partnership (PPP) power projects in Ghana and further determine the critical risk factors affecting both the public and private sectors in PPP power projects.

Ranking-type Delphi survey in two rounds was conducted to establish a comprehensive list of critical risk factors of PPP. Purposive and snowball sampling techniques helped obtain experts for the Delphi survey. Mean score ranking, factor analysis, Cronbach α coefficient and Kendall’s concordance were used for analysis. The probability of occurrence and severity of each risk factor were computed to obtain the risk impact.

From the list of 67 risks, 37 risk factors were deemed to be critical. The five topmost risk factors were: delay payment on contract, private investor change, political risks, fluctuating demand of power generated and public opposition. Principal component analysis grouped the risk factors into seven major themes.

This study develops an authoritative risk factor list for PPP power projects, which reflects both sector and country conditions for prioritizing and mitigating risk factors. Delphi approach adopted in this study can be used by future studies in similar environments where PPP is novel and expert respondents scarce.

This study aims to provide a new method for precisely sizing photovoltaic (PV) arrays for standalone, direct pumping PV Water Pumping (PVWP) systems for irrigation purposes.

The method uses historical weather data and considers daily variability in regional temperatures and rainfall, crop evapotranspiration rates and seasonality effects, all within a nonparametric bootstrapping approach to synthetically generate daily rainfall and crop irrigation needs. These needs define the required daily supply of pumped water to achieve a user-specified level of reliability, which provides the input to an intuitive approach for PV array sizing. An economic comparison of the costs for the PVWP versus a comparably powered diesel generator system is provided.

Pumping 22.8646 m³/day of water would meet the pasture crop irrigation needs on a one-acre (4046.78 m²) tract of land in South Florida, with 99.9% reliability. Given the specified assumptions, an 8.4834 m² PV array, having a peak power of 1.1877 (kW), could provide the 1.2347 (kWh/day) of hydraulic energy needed to supply this volume over a total head of 20 meters. The PVWP system is the low-cost option when diesel prices are above $0.90/liter and total installed PV array costs are fixed at $2.00/Watt peak power or total installed PV array costs are below $1.50/Watt peak power and diesel prices are fixed at $0.65/liter.

Because the approach is not dependent on the shapes of the sampling distributions for regional climate factors and can be adapted to consider different types of crops, it is highly portable and applicable for precisely determining array sizes for standalone, direct pumping PVWP systems for irrigating diverse crop types in diverse regions.

This paper aims to introduce the quasi impedance source inverter (qZSI)-based static compensator (STATCOM), which is incorporated into the hybrid distributed power generation system for enhancement of power quality. The distributed power generation system includes the photovoltaic (PV), wind energy conversion system (WECS) and battery energy storage system.

The WECS is used by the self-excited induction generator (SEIG) and the flywheel energy storage system (FESS). To regulate its terminal voltage and frequency, the SEIG requires adjustable volt-ampere reactive (VAR). A combination of a STATCOM and a fixed condenser bank usually serves to satisfy the VAR demand. The maximum correntropy criterion-based adaptive filter technique (AFT) is proposed to control the qZSI-STATCOM and to guarantee that the voltage at the SEIG terminal is harmonic-free while providing non-linear three-phase and single-phase loads.

The coordinated operation of the suggested voltage control and flywheel control systems ensures that load voltage and frequency are retained in their respective values at very low harmonic distortions regardless of wind speed and load variation. The simulation and experimental studies are carried out under different load conditions to validate the efficiencies of the PV-assisted STATCOM.

To improve system stability and minimize total costs, extra load current sensors can also be avoided. This paper proposes to control the SEIG terminal voltage and harmonic elimination in the standalone WECS systems using maximum correntropy criterion-based AFT with a fuzzy logic controller.

Reference voltage or current generators are an important requirement for an analog or digital circuit design. Bandgap reference circuits (BGR) are most common way of generating the reference voltage. This paper aims to provide a detailed insight of design of a folded cascode operational amplifier (FC op amp) and a BGR circuit. The complete study flow from design to layout of the circuits on 180 nm semiconductor laboratory (SCL) process leading to bonding diagram for possible tape-out is discussed. This study work has been supported by MeitY, Govt. of India, through Special Manpower Development Project Chip to System Design.

This paper provides a detailed insight in design of a FC op amp and a BGR circuit. The complete study flow from design to layout of the two circuits on 180 nm SCL process leading to bonding diagram for possible tape-out is discussed. Section 2 shows the design of FC op amp, beta-multiplier circuit and their simulation results. Section 3 describes the comparison of design of conventional BGR and the proposed BGR with other state-of-art BGR circuits. Section 4 gives the comparison of their performance. The conclusion is given in Section 5.

The post-layout simulation of FC op amp show an open-loop gain of 64.5 dB, 3-dB frequency of 5.5 KHz, unity-gain bandwidth of 8.7 MHz, slew rate of 8.4 V/µs, CMRR of 111 dB and power of 25.5µW. Among the two BGR designs, the conventional BGR generated 693 mV of reference voltage with a temperature coefficient of 16 ppm/°C the other BGR, with curvature correction generated 1.3 V of reference voltage with a temperate coefficient of 6.3 ppm/°C , both results in temperature ranging from −40°C to 125°C. The chip layout of the circuits designed on 180 nm SCL process ensures design rule check (DRC), Antenna and layout versus schematic (LVS) clean with metal fill.

Slew rate, stability analysis, power are important parameters which should be taken care while designing an op amp for a BGR. Direct current gain should be kept higher to reduce offset errors. Input common mode range is decided by the operating temperature range. A higher power supply rejection ratio will reduce BGR sensitivity to supply voltage variations. Input offset should be kept low to reduce BGR error in reference voltage. However, this paper emphasis on the flow from schematic to layout using simulation tools. As part of the study, the bonding diagram for tape-out of BGR and FC design in the given SCL frame size with seal ring is also explored, for possible tape-out.

Reference voltage or current generators are an important requirement for an analog or digital circuit design. BGR are most common way of generating the reference voltage. This paper provides a detailed insight in design of a FC op amp and a BGR circuit. The complete study flow from design to layout of the circuits on 180 nm SCL process leading to bonding diagram for possible tape-out is discussed. The chip layout of the circuits was designed on 180 nm SCL process ensuring DRC, antenna and LVS clean with metal fill using Cadence virtuoso and Mentor Graphics Calibre simulation tools.

BGR are most common way of generating the reference voltage. This paper gives a detailed insight of a BGR design using a folded-cascode operational amplifier. The FC op amp is biased using a beta multiplier circuit and high-swing cascode current mirror circuit. The paper discuss FC circuit design flow from schematic to layout.

FC op amp is biased using a beta multiplier circuit and high-swing cascode current mirror. The paper discusses FC design flow from schematic to layout. The circuits were designed on 180 nm SCL technology with 1.8 V of power supply. The post-layout simulation show an open-loop gain of 64.5 dB, 3 dB frequency of 5.5 KHz, unity-gain bandwidth of 8.7 MHz, slew rate of 8.4 V/µs, CMRR of 111 dB and power of 25.5 µW. BGR were designed using FC op amp. The proposed BGR generated 1.3 V of reference voltage with a temperature coefficient of 6.3 ppm/°C in the range from −40°C to 125°C in schematic simulation.

These implementations not only generate excessive voltage levels to enhance the quality of power but also include a detailed investigating of the various modulation methods and control schemes for multilevel inverter (MLI) topologies. Reduced harmonic modulation technology is used to produce 11-level output voltage with the production of renewable energy applications. The simulation is done in the MATLAB/Simulink for 11-level symmetric MLI and is correlated with the conventional inverter design.

This paper is focused on investigating the different types of asymmetric, symmetric and hybrid topologies and control methods used for the modular multilevel inverter (MMI) operation. Classical MLI configurations are affected by performance issues such as poor power quality, uneconomic structure and low efficiency.

The variations in both carrier and reference signals and their performance are analyzed for the proposed inverter topologies. The simulation result compares unipolar and bipolar pulse-width modulation (PWM) techniques with total harmonic distortion (THD) results. The solar-fed 11-level MMI is controlled using various modulation strategies, which are connected to marine emergency lighting loads. Various modulation techniques are used to control the solar-fed 11-level MMI, which is connected to marine emergency lighting loads. The entire hardware system is controlled by using SPARTAN 3A field programmable gate array (FPGA) board and the least harmonics are obtained by improving the power quality.

The simulation result compares unipolar and bipolar PWM techniques with THD results. Various modulation techniques are used to control the solar-fed 11-level MMI, which is connected to marine emergency lighting loads. The entire hardware system is controlled by a SPARTAN 3A field programmable gate array (FPGA) board, and the power quality is improved to achieve the lowest harmonics possible.

The decision to select one amongst many choices of higher education institutions (HEIs) is a complex process. At a theory-building level, this study investigates the determinants of students' decisions as they consider investing in a long-term credence service higher education (HE) contract in pre- and in-pandemic and the implications for education managers. The second aspect is how disruptive global events influence such choice-making.

The study hypothesized that there would be significant differences in the driving factors and their weight in students' decisions seeking admission into B-schools (Business schools). Structural equation modeling (SEM) and t-test validate the determinants and test hypothesized differences.

Results reveal that core faculty quality, industry exposure, institutional brand name, placement offered, return on investment and specializations offered are the preferred choice criteria. The results reveal that choice criteria in the pre-and in-pandemic differ significantly.

The application of the SEM approach on a large primary database of students during the pre and in-pandemic periods to understand the changes in the choice of B-school for admission is the original aspect of the paper. Insights from the four hypotheses which got rejected provide value to stakeholders. As the pandemic is rearing its head once again across the globe, this study would be able to inform admissions managers on how to navigate for admissions success.

Tactile communication that relies on the human sense of touch replicated using vibration motors is increasingly being explored for seamless communication on construction jobsite. However, the technological efficacy cannot secure the users’ acceptability of the tactile communication devices. This study aims to assess the factors affecting the wearability of such a portable tactile device based on the responses from practicing professionals.

The investigation adapted a three-step phenomenological interviewing approach to seek feedback from construction personnel in Texas, the USA, regarding the viability of wearable tactile communication. The interviewees expressed various opinions about the on-body placement upon exposure to a portable tactile feedback prototype developed for this study, which was used to derive inferences regarding the factors affecting its on-field acceptability.

All the participants of the round-table study (11 out of 11) considered tactile feedback as a viable mode of communication on construction jobsite. Seven professionals supported the integration of a tactile device with the hard hat, whereas the rest preferred tactile eyeglasses. Weatherability, rechargeability, traceability, safety and social receptivity were identified as the major factors affecting the on-body placement of the wearable tactile communication device.

This paper presents a roadmap to gain construction industry opinion on the factors that can affect the on-body placement of a wearable tactile communication device. The five aforementioned factors impacting tactile communication acceptability were used to evaluate 10 potential on-body placements. The findings have implications for research and development of wearable tactile devices and the subsequent acceptability of such a device on the jobsite.

This article aims to explore the advantages of integrating a new generative artificial intelligence (AI) technology in education. It investigates the use of ChatGPT in personalized learning, assessment and content creation and examines ways to manage its limitations and some ethical considerations. The purpose is to stimulate discussion on the effective application of ChatGPT as a tool for learning and skill development while remaining mindful of the ethical issues involved.

The methodology in this article includes four steps: a literature search, screening and selection, analysis and synthesis. The literature was thoroughly screened and selected on the basis of its relevance to the research question, before selected material were carefully read and analyzed. The insights gained from this analysis were then synthesized to identify key considerations in integrating ChatGPT in education.

The study concludes that ChatGPT can be effectively integrated into education to automate routine tasks and enhance the learning experience for students, ultimately increasing productivity and efficiency and fostering adaptive learning. However, the limitations of ChatGPT, even when updated, must be borne in mind, including factual inconsistencies, potential bias promotion, lack of in-depth understanding and safety concerns. The study nevertheless highlights the benefits of responsibly integrating ChatGPT within the field of education.

This study has practical implications for educators and policymakers who are interested in the integration of AI technology in education. The study provides insights of using ChatGPT in education.

This article contributes to the existing literature by specifically examining the advantages of integrating ChatGPT in higher education and offering recommendations for its responsible use. Moreover, the article emphasizes ethical considerations in the context of ChatGPT integration.

This study aims to develop a taxonomy of requirements for mobile BIM technologies (MBT), clarify the relating terms and concepts, and identify the interactions between MBT features and the construction management functions on sites.

A positivist approach with elements of interpretivism is adopted to allow to capture what is perceived as “reality” in relation to individuals’ interpretation and experience in the use and implementation of MBT. This is achieved by using a mixed qualitative-quantitative approach that can capture the various understandings of MBT. The research methods included a longitudinal case study over 12 months, two project workshops, expert interviews and an industry survey that together helped to investigate MBT at project, enterprise and industry levels.

The MBT requirements taxonomy included requirements relating to both project and organisation. Project requirements addressed MBT functionalities for sites and information management, while organisation requirements focused on the integration of MBT solutions with the enterprise from information technology, legal and security perspectives. A detailed matrix showing the interactions between five key MBT features and seven construction management functions was also developed.

The two constructs developed by this study can help researchers to structure their investigation of key uses of MBT applications and their benefits. It can be used by researchers aiming to investigate integrated approaches to the digitalisation of construction sites, such as those enabled by Digital Twins. The interaction matrix can aid researchers in evaluating the intersections between the MBT functionalities and the site construction management functions (e.g. theoretical analysis of interactions from Lean Construction, benefit evaluation perspective). More broadly, the two constructs can support research and practice investigating the development of data-driven approaches on construction sites.

The developed MBT taxonomy can guide construction organisations in selecting suitable MBT for Field BIM for their projects. It can also act as a baseline against which varying MBT solutions can be compared.

Constructs such as taxonomies for MBTs; an understanding of MBT capabilities and use within the industry; and a lack of delineation between related terms, such as Mobile BIM, Field BIM, Site BIM, Cloud BIM and Mobile Apps, were lacking in the literature. This study contributed to addressing this gap.