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This paper aims to present a comprehensive review of the laser engineered net shaping (LENS) process in an attempt to provide the reader with a deep understanding of the controllable and fixed build parameters of metallic parts. The authors discuss the effect and interplay between process parameters, including: laser power, scan speed and powder feed rate. Further, the authors show the interplay between process parameters is pivotal in achieving the desired microstructure, macrostructure, geometrical accuracy and mechanical properties.

In this manuscript, the authors review current research examining the process inputs and their influences on the final product when manufacturing with the LENS process. The authors also discuss how these parameters relate to important build aspects such as melt-pool dimensions, the volume of porosity and geometry accuracy.

The authors conclude that studies have greatly enriched the understanding of the LENS build process, however, much studies remains to be done. Importantly, the authors reveal that to date there are a number of detailed theoretical models that predict the end properties of deposition, however, much more study is necessary to allow for reasonable prediction of the build process for standard industrial parts, based on the synchronistic behavior of the input parameters.

This paper intends to raise questions about the possible research areas that could potentially promote the effectiveness of this LENS technology.

The purpose of this paper is to compile a comprehensive status report on pipes/piping networks across different industrial sectors, along with specifications of materials and sizes, and showcase welding avenues. It further extends to highlight the promising friction stir welding as a single solid-state pipe welding procedure. This paper will enable all piping, welding and friction stir welding stakeholders to identify scope for their engagement in a single window.

The paper is a review paper, and it is mainly structured around sections on materials, sizes and standards for pipes in different sectors and the current welding practice for joining pipe and pipe connections; on the process and principle of friction stir welding (FSW) for pipes; identification of main welding process parameters for the FSW of pipes; effects of process parameters; and a well-carved-out concluding summary.

A well-carved-out concluding summary of extracts from thoroughly studied research is presented in a structured way in which the avenues for the engagement of FSW are identified.

The implications of the research are far-reaching. The FSW is currently expanding very fast in the welding of flat surfaces and has evolved into a vast number of variants because of its advantages and versatility. The application of FSW is coming up late but catching up fast, and as a late starter, the outcomes of such a review paper may support stake holders to expand the application of this process from pipe welding to pipe manufacturing, cladding and other high-end applications. Because the process is inherently inclined towards automation, its throughput rate is high and it does not need any consumables, the ultimate benefit can be passed on to the industry in terms of financial gains.

To the best of the authors’ knowledge, this is the only review exclusively for the friction stir welding of pipes with a well-organized piping specification detailed about industrial sectors. The current pipe welding practice in each sector has been presented, and the avenues for engaging FSW have been highlighted. The FSW pipe process parameters are characteristically distinguished from the conventional FSW, and the effects of the process parameters have been presented. The summary is concise yet comprehensive and organized in a structured manner.

This paper aims to present a new design in the area of basal osseointegrated implant (BOI) for oral and maxillofacial surgery using a patient-specific computer-aided design (CAD) and additive manufacturing (AM) approach. The BOI was designed and fabricated according to the patient’s specific requirement, of maxilla stabilisation and dental fixation, a capacity not currently available in conventional BOI. The combination of CAD and AM techniques provides a powerful approach for optimisation and realisation of the implant in a design which helps to minimise blood loss and surgery time, translating into better patient outcomes and reduced financial burdens on healthcare providers.

The current study integrates the capabilities of conventional medical imaging techniques, CAD and metal AM to realise the BOI. The patient’s anatomy was scanned using a 128-slice spiral computed tomography scanner into a standard Digital Imaging and Communication in Medicine (DICOM) data output. The DICOM data are processed using MIMICS software to construct a digital representative patient model to aid the design process, and the final customised implant was designed using Creo software. The final, surgically implanted BOI was fabricated using direct metal laser sintering in titanium (Ti-64).

The current approach assisted us to design BOI customised to the patient’s unique anatomy to improve patient outcomes. The design realises a nerve relieving option and placement of porous structure at the required area based up on the analysis of patient bone structural data.

The novelty in this work is that developed BOI comprises a patient-specific design that allows for custom fabrication around the patients' nerves, provides structural support to the compromised maxilla and comprises a dual abutment design, with the capacity of supporting fixation of up to four teeth. Conventional BOIs are only available for a signal abutment capable of holding one or two teeth only. Given the customised nature of the design, the concept could easily be extended to explore a greater number of fixation abutments, abutment length/location, adjusted dental fixation size or greater levels of maxilla support. The study highlights the significance of CAD packages to construct patient-specific solution directly from medical imaging data, and the efficiency of metal AM to translate designs into a functional implant.

Sustainability has become a priority for companies due to pressure from multiple stakeholders. In an overly competitive market, shareholders push for economic results, allowing lean manufacturing to establish itself as dominant paradigm in manufacturing. However, concerns grow regarding how lean implementation can allow companies to achieve sustainable development goals, or, if the resources required for a successful lean implementation can result in a detriment of environmental and social performance. This paper intends to help close the knowledge gap regarding the effects of lean manufacturing on sustainable performance from a triple bottom line perspective, and how operational, environmental and social outcomes interact between themselves.

Two models for the interaction between lean and sustainability were proposed. The first is called the “sand-cone” model, which poses that performance improvements derived from lean are cumulative on each one of the sustainability dimensions. The second is called the “trade-offs” approach. In this case, the resources required to improve one dimension of sustainability clash with those required by the others. Data were gathered from a sample of 133 Colombian metalworking companies and processed using structural equations models.

The results support the cumulative “sand-cone”, which follows a sequence of operational-environmental-social improvement in the presence of lean. For the “trade-offs” model, partial evidence suggests that they can occur in detriment of social performance.

The “sand-cone” and “trade-offs” are empirically tested for the first time in the context of sustainability, providing further knowledge into its interaction with lean manufacturing. The models’ results contribute to practitioners by providing a tested path for companies to improve their performance in a cumulative sequence that will provide better long-term results.

This paper aims to evaluate the risk factors and determines the overall risk level (ORL) of public-private-partnership (PPP) power projects in Ghana using fuzzy synthetic evaluation methodology (FSEM).

In this paper review of literature led to the development of a 67-factor risk list which was ranked by experts and industry practitioners through a questionnaire survey.

These factors were grouped into principal risk factors (PRFs) using component analysis and they served as the input variables for fuzzy analysis. The seven components were: Contract and Payment risks, Environmental risks, Financial and Cost risks, Legal and Guarantee risks, Operation risks, Socio-Political and Performance risks (SPR) and Tender and Negotiation risks. Study showed that the ORL of Ghanaian PPP power projects is high implying they are risky to both the public and private sectors. Fuzzy analysis also confirmed SPR as the most critical principal factor.

This study is significant and demonstrates that fuzzy methodology can be used as a useful risk evaluation tool and risk assessment framework for private investors, policy makers and public sector.

The scarcity of literature related to the PPP (public-private partnership) barriers in construction projects within war areas, and hence the dearth of information to deliver viable and effective strategies to those barriers, are the primary causes for the failures of PPP schemes in such areas, particularly in Palestine. Financial and non-financial investments are more problematic in war zones than non-war nations and may escalate barrier for projects' success. The investigation purposes to discover proper answers to the barriers of PPP infrastructure schemes and highlight the execution of barrier reactions.

Specialists were asked to deliver approaches to alleviate 21 barriers and recommend the period needed for applying them. Later, the relevance of alleviation events was examined through prioritization according to the results attained from three elements, i.e. the impact of every barrier and the strategy's viability and efficacy.

While the most unfavorable barrier was finalized to be the unfeasibility of delivering physical security, the most valid answer was associated with the lack of government cohesiveness and responsibility to perform its duties. The discovered barriers are typical within warring nations, but the paper concentrated on Palestine.

This study is an initial effort to examine PPP barriers in Palestinian infrastructure projects. The presented strategies can be applied as a novel set for barrier reaction improvement in occupied nations such as Palestine. Moreover, the results can develop the usage of PPP and enhance the barrier sharing in this scheme.

This paper aims to present a systematic literature review and bibliometric analysis of research papers published on chat generative pre-trained transformer (ChatGPT), an OpenAI-developed large-scale generative language model. The study’s objective is to provide a comprehensive assessment of the present status of research on ChatGPT and identify current trends and themes in the literature.

A total of 328 research article data was extracted from Scopus for bibliometric analysis, to investigate publishing trends, productive countries and keyword analysis around the topic and 34 relevant research publications were selected for an in-depth systematic literature review.

The findings indicate that ChatGPT research is still in its early stages, with the current emphasis on applications such as natural language processing and understanding, dialogue systems, speech processing and recognition, learning systems, chatbots and response generation. The USA is at the forefront of publishing on this topic and new keywords, e.g. “patient care”, “medical”, “higher education” and so on are emerging themes around the topic.

These findings underscore the importance of ongoing research and development to address these limitations and ensure that ChatGPT is used responsibly and ethically. While systematic review research on ChatGPT heralds exciting opportunities, it also demands a careful understanding of its nuances to harness its potential effectively.

Overall, this study provides a valuable resource for researchers and practitioners interested in ChatGPT at this early stage and helps to identify the grey areas around this topic.

The purpose of this study is to examine the research output on “library and information science” (LIS) research domain in South Africa. It also highlights the top LIS research organisations, authors, journals, collaboration types and commonly used keywords. This research will aid in the identification of emerging concepts, trends and advances in this subject.

The Web of Science (WoS), an indexing and abstracting database, served as a tool for bibliographical data. By applying advanced search features, the authors curated data from 1989 to 2021 through the WoS subject category WC = (Information Science & Library Science), limiting the scope to the region, CU = (South Africa), which resulted in 1,034 articles. Moreover, the research focuses on science mapping using the R package for reliable analysis.

The findings reveal that the publications have considerably grown over time, indicating significant attention among researchers in LIS. The findings indicate the critical operator’s performance, existing thematic choices and subsequent research opportunities. The primary topical fields of study that emerged from the bibliometric analysis are impact, information, science, model, management, technology, knowledge and education. Pouris and Fourie are the most productive citations, h-index and g-index. The influential institute was The University of Pretoria.

The use of the WoS database for data collecting limits this study. Because the WoS was the only citation and abstract database used in this study, bibliometric investigations using other citation and abstract databases like “Scopus”, “Google Scholar” and “Dimension” could be interesting. This study presented a bibliometric summary; nevertheless, a systematic and methodical examination of highly cited LIS research publications could throw more light on the subject.

This paper gives valuable information about recent scientific advancements in the LIS and emerging future academic subject prospects. Furthermore, this research work will serve as a reference for researchers in various areas to analyse the evolution of scholarly literature on a particular topic over time.

By identifying the standard channels of study in the LIS discipline, and the essential journals, publications, nations, institutions, authors, data sources and networks in this subject, this bibliometric mapping and visualisation provide new perspectives into academic performance. This paper also articulates future research directions in this realm of knowledge. This study is more rigorous and comprehensive in terms of the analytical procedures it uses.