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The purpose of this paper is to model the convective flows in a room equipped by a glass door and a heated floor of length l = 0.8 × H and submitted to a sinusoidal temperature profile and mono alternative temperature profile.

The paper opts for a numerical study of convective flows in a large scale cavity using the Lattice Boltzmann Method (LBM) by considering a two dimensions (2D) square cavity of side H and filled by air (Pr = 0.71). All the vertical walls, the ceiling and the rest of the floor are thermally insulated, the hot portion of length l = 0.8×H is heated with two imposed temperature profiles of amplitude values 0.2 ≤  a  ≤ 0.6 and for two different periods ζ = ζ0 and ζ = 0.4×ζ0. One of the vertical walls has a cold portion θ_c = 0 that represents the glass door.

A systematic study of the flow structure and heat transfer is carried out considering principal control parameters: amplitude “a” and period ζ for Rayleigh number Ra = 10⁸. Effects of these parameters on results are presented in terms of isotherms, streamlines, profiles of velocities, temperature in the cavity, global and local Nusselt number. It has been found that an increase in amplitude or period increases the amplitude of the temperature in the core of cavity. The Nusselt number increases when the amplitude “a” of the imposed temperature increases, but this later is not affected by variation of the period.

The authors used LBM to simulate the convective flows in a cavity at high Ra, heated from below by tow imposed temperature profiles. Indeed, they simulate a local equipped by a solar water heater (SWH). The floor is subjected to a periodic heating: Sinusoidal heating (Case 1) for which the temperature varies sinusoidally (SWH without a supplement), and mono alternation heating (Case 2), the temperature evolves like a redressed signal (SWH with a supplement). The considered method has been successfully validated and compared with the previous work. The study has been conducted using several control parameters such as the signal amplitude and period in the case of turbulent convection. This allowed us to obtain a considerable set of results that can be used for engineering.

This study attempts to examine the factors that influence user intention to adopt e-procurement in the Nigerian public sector.

A well-structured questionnaire was used to collect primary data from 278 procurement and information technology (IT) departments’ officials of key federal government ministries and agencies. The technology acceptance model (TAM) model was adopted and extended with security-related factors, namely perceived trust and perceived security. A partial least squares-structural equation modelling (PLS-SEM) approach was used to test and validate the model.

The results indicated that perceived usefulness is the best predictor of users’ intention to adopt e-procurement, followed by perceived security and perceived trust. In contrast, however, perceived ease of use was found to have a significant negative effect on the intention to adopt e-procurement.

This study is among the first in the Nigerian public sector context to evaluate users’ perceptions on e-procurement adoption with the use of a distinctive research model (TAM). The study's findings contribute to a better understanding of the factors influencing the adoption of e-procurement in the Nigerian public sector.

The fundamentals of Lean are applicable and can be used in any industry, even non-profit and government organizations, however, there might be certain limitations due to the nature and the specifics of the industry. This study aims to explore what barriers of Lean implementation textile manufacturers might encounter. The authors consider the problem is worth to be explored for the potential to improve the effectiveness of Lean implementation in textile sector companies.

This research was conducted by using qualitative content analysis with open coding of the selected literature followed by empirical research in a Latvian textile manufacturing company.

The presented literature review shows Lean implementation barriers and critical success factors in various industries. The findings from the case study can be divided into two groups. The first confirmed the barriers already identified in the previous research. The second identified industry specific implementation barriers that were not recognized in the related literature.

The original research was limited in scope to one Latvian textile manufacturer, therefore future studies on the subject to confirm the outcome of the research are required.

There is a limited number of studies on the application of Lean in the textile and apparel industry. The literature on Lean implementation in the Latvian manufacturing sector is also limited. The results of this research may have a practical application for textile manufactures considering implementing Lean in their processes.

The aim of this study was to measure the apparent viscosity, flow behavior and density of melon juice as a function of temperature and juice concentration and to obtain simple equations to correlate experimental data.

Melon juice was concentrated in a rotary evaporator to 40±1, 52.5±1 and 65±1°Brix at 50°C, 80 rpm and stored at 4°C until analysis. Density of melon juice was determined with 25 ml pycnometer at 15, 25 and 35°C and was expressed as kg/m3. All experiments were conducted in triplicate. Experimental data were fitted to different models (linear, quadratic, exponential, quadratic exponential and polynomial) using Minitab 16. Significant differences in the mean values were reported at p<0.05. The flow behavior of melon juice was determined using a concentric cylinder rotational viscometer at shear rate range of 13.2-330 s−1 and temperatures of 15, 25 and 35°C. The experimental data were analyzed Slide Write V7.01 Trial Size (p<0.05) and the rheograms was plotted by Microsoft Excel 2007.

Results showed that the four-term polynomial model is the best model for computing density values from temperature and concentration (R2=0.999). The measured shear stress was within 1.69-780 Pa, corresponding to viscosity range of 0.016-0.237 Pa · s. Within the tested conditions, the concentrate exhibited a pseudo plastic behavior. Temperature had an inverse effect on shear stress and apparent viscosity.

No research had been done on production of melon juice concentrate.

This paper aims to explore the intellectual structure shaping the circular economy (CE) discourse within the built environment in Africa.

The study adopted a bibliometric analysis approach to explore the intellectual structure of CE in the built environment in Africa. The authors collected 31 papers published between 2005 and 2021 from the Scopus database and used VOSviewer for data analysis.

The findings show that there are six clusters shaping the intellectual structure: demolition, material recovery and reuse; waste as a resource; cellulose and agro-based materials; resilience and low-carbon footprint; recycling materials; and the fourth industrial revolution. The two most cited scholars had three publications each, while the top journal was Resources, Conservation and Recycling. The dominant concepts included CE, sustainability, alternative materials, waste management, lifecycle, demolition and climate change. The study concludes that there is low CE research output in Africa, which implies that the concept is either novel or facing resistance.

The data were drawn from one database, Scopus; hence, adoption of alternative databases such as Web of Science, Google Scholar and Dimensions could potentially have yielded a higher number of articles for analysis which potentially would result in different conclusions on the subject understudy.

This study made a significant contribution by articulating the CE intellectual structure in the built environment, identified prominent scholars and academic platforms responsible for promoting circularity in Africa.

COVID-19 pandemic interrupted global supply chains (SCs) affecting both developed and developing countries. In context of the COVID-19 pandemic, numerous studies were conducted on sustainable supply chain (SSC) in emerging markets (EMs). However, the contributions of these studies require to be systematically reviewed to provide a platform of knowledge. The purpose of this review is to systematically explore the relevant literature on SSC management during the COVID-19 pandemic in EMs.

The authors applied Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) framework to perform a systematic literature review. Scopus database was used to extract the relevant literature, and 51 journal articles along with 5 conference proceedings were included in the study.

This study identified the major contents along with four different themes, which are the impacts of COVID-19 on the SC, recovery strategies to alleviate the adverse impacts of COVID-19, sustainable practices to improve SC performance and resilience activities to assure firms' survivability. Furthermore, the research reveals that interview/survey/case study–based research and review articles focusing on various industries have dominated the field of SSC management in the context of EMs.

This research enriches the literature by providing an overall scenario of SSC during the COVID-19 pandemic in the context of emerging economies.