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Many public-sector building projects in developing countries are prone to variations owing to the changes made to their original project scopes, and economic depressions and stagnations. Cost and time-overruns are consequences of such variations. Thus, variation management in these projects is important. Hence, this paper aims to analyse the methods of managing variations in public-sector building projects in Sri Lanka.

The study adopted a mixed research approach. Seventeen expert interviews and a questionnaire survey were conducted to identify the causes and consequences of the variations, and the strategies that will help manage those variations. Manual content analysis and mean weighted rankings (MWR) were used to analyse the collected quantitative and qualitative data, respectively.

The employer, consultant, contractor and several other factors are mostly responsible for the variations in public-sector building projects in Sri Lanka. Cost and time-overruns, rework and demolition and disputes are the major consequences of such variations. The study findings reveal that a detailed employer’s brief, clearly defined project objectives, a comprehensive design and set of specifications, and preliminary investigations are the strategies that will mostly minimise the variations in public-sector building projects in Sri Lanka.

The study proposes strategies to avoid or minimise the adverse impact of variations, which the industry practitioners can adopt for variation management in public-sector building projects. The study theoretically contributes to knowledge by revealing how variations in public-sector building projects in Sri Lanka can be managed by identifying their causes and consequences.

In construction projects, underpayments can be recognised as one of the significant drawbacks that impact the success of a project. Research into underpayments is considered ambiguous and provides a limited reflection of the issue, which makes it complicated to trace how it originates in the first place. This study aims to examine the causes that lead to underpayments and develop a holistic synthesis of underpayments for subcontractors in the lifecycle of a construction project.

An open-ended and closed-ended questionnaire was used to collect the data using purposeful sampling with 28 construction stakeholders who ranged from main contractors, subcontractors and others (Small medium enterprises SMEs, Consultancies, Clients etc.). Data collected was analysed to trace drivers and the impact of underpayment and suggested mitigation strategies to be identified whilst viewing the perspectives of a main contractor and subcontractor.

The findings show that the most prominent driver for underpayments is variation disputes followed by cash flow. The research also suggests mitigation strategies such as collaborative working, more robust budget control and early identification of risks as potential remedies to overcome the underpayment issue. The research concludes with a framework that elicits the complexity underlying underpayments for subcontractors in construction projects.

The research evolves the understanding that underpayment is a complex phenomenon, relying heavily on the data/information exchange mechanism between the main contractor and subcontractors. This research provokes the need to understand underpayment further so it can be mitigated.

Project complexity (PC) governs project success, but the project management literature primarily focuses on performance measures and rarely examines the complexity factors, especially for megaprojects. This paper aims to determine the most significant complexity factors for the railway megaprojects in India.

A mixed approach using the Delphi and best–worst method (BWM) helped to identify, validate and determine the most critical factors that require intervention to diminish variance from project performance.

The BWM resulted in stakeholder management, followed by organizational and technological complexity as significant complexity factors, and the varied interests of the stakeholder as the most important among the 40 subfactors.

The finding indicates the necessity for strategic, tactical and operational-level interventions to effectively manage the complexity affecting project efficiency because of the varied stakeholders. This paper will guide the project and general managers to prioritize their resources to handle complexity for effective project performance measured in terms of time, cost and quality and help them make strategic decisions. The research findings of this study are expected to help researchers and practitioners in better planning and smoother execution of projects. In addition, this study would help the researchers formulate policies and strategies for better handling of the projects.

This study adds significant value to the body of knowledge related to PC in megaprojects in developing countries. The result of the investigation underlined that nine complexity factors and seven unique subfactors, namely, the sustainable environment, timely availability of information, communication in both directions, interdepartmental dependency and coordination, design, statutory norms, site challenges, socioeconomic conditions, the tendency of staff to accept new technology and the frequent changes in the requirements of stakeholders are significant in railway megaprojects. The BWM is applied to rank the complexity factors and subfactors in the case area.

The Afghan construction industry faces resource shortages and heavily relies on foreign aid to fund public projects on the path to recovery and reconstruction. While the resource constraints demand cost-efficient delivery of construction projects, many Afghan public projects experience delays and cost overruns. This study aims to evaluate various attributes and factors influencing cost performance in public construction projects in Afghanistan.

The literature review and Delphi method identified 30 cost performance attributes relevant to the context of Afghanistan. Next, a questionnaire survey was conducted with construction management professionals working in the public sector in the Afghan construction industry to evaluate these attributes.

This study found that the lack of resources, poor project management skills and corruption in procurement are the leading causes behind cost overruns in Afghan public projects. This study also identified five latent factors influencing cost performance in public projects in Afghanistan: competency of the project team, socioeconomic and political support, governance and public procurement, planning and risk management and project characteristics.

The exploratory factor analysis did not reveal the relative significance of different cost performance success factors. Moreover, the ranking of cost performance attributes is based on the responses from the public sector construction professionals only.

The construction industry in Afghanistan significantly contributes to the country’s social and economic growth and employment. This study’s findings will help researchers, project sponsors, government departments and industry practitioners interested in improving the cost performance in Afghan public projects.

Given the scarcity of research in war-affected and conflict-sensitive regions, this study fills a research gap on project cost performance by providing insights into the cost performance success factors in public projects in Afghanistan.

The purpose of this paper is to improve the conductivity and processability of polyaniline (PANI).

The study opted for synthesis of the conductive PANI/polyvinyl alcohol (PVA) composite film, co-doped with 5-sulphosalicylic acid and sulphuric acid. Using an electrochemical method, a small amount of silver (Ag) was electrodeposited on the film. The PVA/PANI and PVA/PANI/Ag composite films were characterised by scanning electron microscope, X-ray diffraction and infrared. The composite deposition mechanism of the composite film was investigated by cyclic voltammetry for the first time.

The conductivity of the optimum PVA/PANI composite film reached 21.2 S · cm⁻¹.Then, a small amount of Ag was deposited on the PVA/PANI film, and the conductivity significantly increased by 1250 S · cm⁻¹. Through appropriate degree of stretching, the conductivity of the films was enhanced. The results indicate that uniform PVA/PANI fibres and dendritic Ag can combine to form complete three-dimensional conductive networks that exhibit better conductivity and mechanical properties. The cyclic voltammetry curves reveal that the dedoping potential of PANI was more negative than the reduction potential of Ag. Therefore, the procedure for the deposition of Ag on the PANI/PVA composite film cannot decrease the conductivity.

This paper for the first time described and revealed the effective and practical synthesis approach and composite mechanism to prepare multi-types metal-conductive polymer composites and improve the conductivity of a conductive polymer with a less expense and one-step electrochemical method.

This paper first explored galvanostatic oxidation to synthesise a PANI composite film to resolve the processability and conductivity of PANI by co-doped with mixed acids and deposited Ag on film. Furthermore, for the first time, the composite mechanism of metal and conductive polymer was studied.

The aim of the present research was to study and model drying of loquat fruit under vacuum conditions at three temperatures to select the best mathematical model for predicting drying rate of loquat during times which is used in designing of vacuum dryer. The dried product may be used in the preparation of soups, jam, premixed foods, snacks, etc.

Loquat samples were dried by vacuum oven (52 cm Hg) at three temperatures, 60, 70 and 80°C. First, moisture content was plotted against time for each treatment and after that moisture ratio curves were plotted. These curves were fitted with nine well-known models to select the best model.

Regression analysis of different models and values of RMSE and χ2 showed that page model had the best fitness due to highest R2 and lowest RMSE and χ2. Moisture diffusivity of loquat samples at 60, 70 and 80°C was calculated to be 6.87×10−10, 9.17×10−10 and 1.29×10−9 m2/s, respectively, which increased with temperature.

This paper is believed to be the only one which investigates and models drying loquat under vacuum conditions to select the best mathematical model for predicting drying rate of loquat.

A new coupled model is developed to simulate the interaction between fluid droplet collisions on discrete particles (DPs) by using mathematic function.

In this model, the smoothed particle hydrodynamics (SPH) is used based on the kernel function and the time step which takes into consideration to the fluid domain in accordance with the discrete element method (DEM) with resistance function. The interaction between fluid and DPs consists of three parts, which are repulsive force, viscous shear force and attractive force caused by the capillary action. The numerical simulation of droplet collision on DPs presents the whole process of droplet motion. Otherwise, an experimental data were conducted to record the realistic process for verification.

The comparison result indicated that the numerical simulation is capable of capturing the entire process for droplet collision on DPs.

However, based on the difference of experimental environment, type of the DP and setups, the maximum spreading dimeters of could not fit the experimental data exactly.

In sum, the coupled SPH-DEM method simulation shows that the coupled model of SPH-DEM developed an entire effectiveness process for fluid–solid interaction problem.

The purpose of this study is to examine the state of research into adoption of machine learning systems within the health sector, to identify themes that have been studied and observe the important gaps in the literature that can inform a research agenda going forward.

A systematic literature strategy was utilized to identify and analyze scientific papers between 2012 and 2022. A total of 28 articles were identified and reviewed.

The outcomes reveal that while advances in machine learning have the potential to improve service access and delivery, there have been sporadic growth of literature in this area which is perhaps surprising given the immense potential of machine learning within the health sector. The findings further reveal that themes such as recordkeeping, drugs development and streamlining of treatment have primarily been focused on by the majority of authors in this area.

The search was limited to journal articles published in English, resulting in the exclusion of studies disseminated through alternative channels, such as conferences, and those published in languages other than English. Considering that scholars in developing nations may encounter less difficulty in disseminating their work through alternative channels and that numerous emerging nations employ languages other than English, it is plausible that certain research has been overlooked in the present investigation.

This review provides insights into future research avenues for theory, content and context on adoption of machine learning within the health sector.

The purpose of this paper is to understand the similarities and differences between the Twitter users who tweeted on journal articles in psychology and political science disciplines.

The data were collected from Web of Science, Altmetric.com, and Twitter. A total of 91,826 tweets with 22,541 distinct Twitter user profiles for psychology discipline and 29,958 tweets with 10,478 distinct Twitter user profiles for political science discipline were used for analysis. The demographics analysis includes gender, geographic location, individual or organization user, academic or non-academic background, and psychology/political science domain knowledge background. A machine learning approach using support vector machine (SVM) was used for user classification based on the Twitter user profile information. Latent Dirichlet allocation (LDA) topic modeling was used to discover the topics that the users discussed from the tweets.

Results showed that the demographics of Twitter users who tweeted on psychology and political science are significantly different. Tweets on journal articles in psychology reflected more the impact of scientific research finding on the general public and attracted more attention from the general public than the ones in political science. Disciplinary difference in term of user demographics exists, and thus it is important to take the discipline into consideration for future altmetrics studies.

From this study, researchers or research organizations may have a better idea on who their audiences are, and hence more effective strategies can be taken by researchers or organizations to reach a wider audience and enhance their influence.

The purpose of this paper is to study assembling parameters in dye-sensitised solar cells (DSSCs) performance. For this end, 3a,7a-dihydroxy-5ß-cholanic acid (cheno) are selected as anti-aggregation agent and two solutions, namely, tetrabutyl ammonium iodide and (PMII)IL used as electrolyte.

A series of organic dyes were selected using N-substituents carbazole as electron donor group and acrylic acid and cyanoacrylic acid as electron acceptor groups. Absorption properties of purified dyes were studied in solution and on photoelectrode substrate. DSSCs were prepared in the presence of anti-aggregation agent and different electrolyte to determine the photovoltaic performance of each dyes.

The results showed that all organic dyes form J-aggregation on the photoanode substrate in the absence of anti-aggregation agent and the amounts of aggregation were reduced in the presence of anti-aggregation agent. DSSCs were fabricated in the presence of anti-aggregation agent. The photovoltaic properties were improved using tetrabutyl ammonium iodide as electrolyte. The maximum power conversion efficiency was achieved for D12 in the presence of cheno and tetrabutyl ammonium iodide as anti-aggregation agent and electrolyte, respectively.

Organic dye attracts more and more attention due to low cost, facile route synthesis and less hazardous.

The effect of anti-aggregation agent and electrolyte on DSSCs performance was investigated for the first time.