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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.

Cushioning is a useful material property applicable for a range of applications from medical devices to personal protective equipment. The current ability to apply cushioning in a product context is limited by the appropriateness of available materials, with polyurethane foams being the current gold standard material. The purpose of this study is to investigate additively manufactured flexible printing of scaffold structures as an alternative.

In this study, this study investigates triply periodic minimal surface (TPMS) structures, including Gyroid, Diamond and Schwarz P formed in thermoplastic polyurethane (TPU), as a possible alternative. Each TPMS structure was fabricated using material extrusion additive manufacturing and evaluated to ASTM mechanical testing standard for polymers. This study focuses attention to TPMS structures fabricated for a fixed unit cell size of 10 mm and examine the compressive properties for changes in the scaffold porosity for samples fabricated in TPU with a shore hardness of 63A and 90A.

It was discovered that for increased porosity there was a measured reduction in the load required to deform the scaffold. Additionally, a complex relationship between the shore hardness and the stiffness of a structure. It was highlighted that through the adjustment of porosity, the compressive strength required to deform the scaffolds to a point of densification could be controlled and predicted with high repeatability.

The results indicate the ability to tailor the scaffold design parameters using both 63A and 90A TPU material, to mimic the loading properties of common polyurethane foams. The use of these structures indicates a next generation of tailored cushioning using additive manufacturing techniques by tailoring both geometry and porosity to loading and compressive strengths.

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.

Although literature abounds on lean sustainability (LS), its contributions to manufacturing industries’ triple bottom line performance (TBLP) through top management commitment (TMC) remain scanty. This research explores the mediating role of TMC in the nexus between LS and TBLP.

Given the study’s quantitative focus, the causal design was utilised. The structured questionnaire, a survey instrument, was used to gather primary data from 285 manufacturing organisations in Ghana, a developing country. Data analysis was done with structural equation modelling.

It was found that LS and TMC positively influence TBLP, whereas TMC partially mediates the connection between LS and TBLP of Ghanaian manufacturing organisations.

The study concentrates on Ghana’s manufacturing industry and embraces the stakeholder theory and quantitative methods.

This research underlines why top managers must prioritise investment in LS to promote sustainable development and attain their organisations’ TBLP targets. The study also provides key insights for top managers to consistently commit enormous resources towards developing lean practices, contributing favourably to TBLP. By establishing the interplay among LS, TMC and TBLP, manufacturing practitioners and researchers can further advance new strategies to address the growing sustainability concerns and achieve higher economic, social and environmental performance.

The study’s originality lies in analysing the mediation effect of TMC on the linkage between LS and TBLP in a developing economy where manufacturing organisations are continuously exposed to resource and waste management problems and lack adequate commitments from top managers towards sustainability initiatives. It is also the first to establish relationships between top management commitment and TBLP in the manufacturing industries of developing economies, concentrating on Ghana.

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.

To analyze the integration of the circular economy and Industry 4.0 in agtechs through lean integration and people.

Following in-depth interviews with key informants, data tabulation was performed via families of viewpoints supported by the primary elements mapped in the investigated context.

The integration of the circular economy with Industry 4.0, and integrated into lean production, aiming to eliminate waste and maximize customer value, and the valorization of people are fundamental in the context of recycling, reuse and reutilization of materials not only in the agricultural sector but also, since it is the object of study of this research. The use of I4.0 technologies and solutions, such as applications, sensors, artificial intelligence and digital platforms, allows for the collection and analysis of real-time data, facilitating decision-making and monitoring of agricultural operations.

The research limitations may include the limited sample of Agtechs analyzed, which might not cover all innovations and trends existing in the sector; data and information available up to the study date (April 2023), which might not reflect more recent developments in the field of Agtechs and the circular economy.

The circular economy seeks to minimize waste and maximize resource use, promoting recycling, reusing and repurposing of materials. In contrast, Industry 4.0 refers to the application of advanced technologies such as artificial intelligence, the internet of things and automation to optimize productive processes and make them more efficient. Lean integration, which aims to eliminate waste and maximize customer value, and the appreciation of people are fundamental in this context.

The use of technologies and solutions from Industry 4.0, like apps, sensors, artificial intelligence and digital platforms, allows real-time data collection and analysis, facilitating decision-making and monitoring of agricultural operations. In addition, the provision of online consulting and technical assistance services contributes to producer training and the maximization of results.

Significant benefits for the agricultural sector, such as greater efficiency, sustainability, product quality, traceability, cost reduction and productivity increase. The use of advanced technologies and the valorization of people are key elements to drive this integration and promote digital transformation in the field. The integration of the circular economy and Industry 4.0 in agtechs, integrating lean production and people.

Today’s businesses are looking for a circular bioeconomy (CBE) to develop a sustainable manufacturing process as industrial operations result in significant amounts of waste materials and the depletion of natural sources. The industry commonly applies techniques such as lean manufacturing (LM), digital innovations (DI) and green practices (GP) for operational and quality improvement. However, publications explaining how these technologies enable the CBE transition are scarce. This study examines CBE components, common practices of each technology facilitating the CBE transition, problems of solitary technology deployment as well as coupling technologies for the CBE transition.

A scoping review was conducted to analyse previous studies in this new field. The data collection is in a quantitative manner, but the data synthesis process follows a similar method of synthesising data in the grounded theory method, which includes familiarisation with the data, open-coding and finalisation of the themes.

Critical components of CBE were identified as biobased goods, industry symbiosis, material resource efficiency, renewable energy, product lifecycle and sharing economy. GP is the most prominent in moderating the CBE transition. We identify each technology has coupled relationships (Lean-4.0, Green-Lean and Green-4.0) technologies facilitated by the circularity concept, which form the core pillars of enablers and advance the CBE paradigm.

This study demonstrates that combining lean principles with green technology and digital technologies can effectively decrease waste and resource usage in biobased manufacturing processes, therefore endorsing the concept of resource efficiency in circular bioeconomy models.

The results allow entrepreneurs to strategically incorporate different existing technologies to meet CBE fundamental objectives by initiating it with dual technologies and facilitate industry professionals and regulators to support the improvement of environmental sustainability performance in the manufacturing industry. The management will be able to focus on the common practices across the technologies, which have a dual benefit for both operational and environmental performance.

The paper makes the first attempt to present the synergic impact of the three quality management technologies on a new concept of sustainability, CBE.

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.