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In this paper, the authors prove that the Douglas space of second kind with a generalised form of special (α, β)-metric F, is conformally invariant.

For, the authors have used the notion of conformal transformation and Douglas space.

The authors found some results to show that the Douglas space of second kind with certain (α, β)-metrics such as Randers metric, first approximate Matsumoto metric along with some special (α, β)-metrics, is invariant under a conformal change.

The authors introduced Douglas space of second kind and established conditions under which it can be transformed to a Douglas space of second kind.

This study aims to map and analyze health-care pricing information research. This work highlights current gap in pricing information research in health care and proposes future research avenues to academia and industry professionals.

A bibliometric method was adopted to analyze extant literature on pricing information asymmetry. Semistructured interviews were conducted with key stakeholders in health care to triangulate the findings.

Pricing information is crucial for all stakeholders including health-care consumers, providers and regulators. The popular research areas were the rising health-care cost, cost-saving, outcome-based pricing, price based on service supply and demand, insurance and out-of-pocket spending. Cost–quality perceived linkages, cost–demand correlation in health-care service and cost–price interlinked drivers were the dominant themes in extant literature. The study highlighted that pricing information asymmetry pushed patients from weaker sections into a debt trap due to unplanned out-of-pocket health-care expenses. The study suggests areas of research to minimize this pricing information asymmetry.

The emerging themes in health pricing asymmetry will help key stakeholders to identify areas for improvement and take remedial actions in the health-care domain.

This study is a pioneering effort to summarize extant literature published in the health-care information pricing domain and analyze it from a bibliometric perspective. The study also triangulates the finding with primary data from key stakeholders and highlights emerging research areas.

Scaffolds are essentially required to have open porous structure for facilitating bone to grow. They are generally placed on those bone defective/fractured sites which are more prone to compressive loading. Open porous structure lacks in strength in comparison to solid. Selective laser sintering (SLS) process is prominently used for fabrication of polymer/composite scaffolds. So, this paper aims to study for fabrication of three-dimensional open porous scaffolds with enhanced strength, process parameters of SLS of a biocompatible material are required to be optimized.

Regular open porous structures with suitable pore size as per computer-aided design models were fabricated using SLS. Polyamide (PA-2200) was used to fabricate the specimen/scaffold. To optimize the strength of the designed structure, response surface methodology was used to design the experiments. Specimens as per ASTM D695 were fabricated using SLS and compressive testing was carried out. Analysis of variance was done for estimating contribution of individual process parameters. Optimized process parameters were obtained using a trust region algorithm and correlated with experimental results. Accuracy of the fabricated specimen/scaffold was also assessed in terms of IT grades. In vitro cell culture on the fabricated structures confirmed the biocompatibility of polyamide (PA-2200).

Optimized process parameters for open cell process structures were obtained and confirmed experimentally. Laser power, hatch spacing and layer thickness have contributed more in the porous part’s strength than scan speed. The accuracy of the order of IT16 has been found for all functional dimensions. Cell growth and proliferation confirmed biocompatibility of polyamide (PA-2200) for scaffold applications.

This paper demonstrates the biocompatibility of PA-2200 for scaffold applications. The optimized process parameters of SLS process for open cell structure having pore size 1.2 × 1.2 mm² with strut diameter of 1 mm have been obtained. The accuracy of the order of IT16 was obtained at the optimized process factors.

The purpose of this paper is to critically review the literature related to dimensional accuracy and surface roughness for fused deposition modeling and similar extrusion-based additive manufacturing or rapid prototyping processes.

A systematic review of the literature was carried out by focusing on the relationship between process and product design parameters and the dimensional and surface properties of finished parts. Methods for evaluating these performance parameters are also reviewed.

Fused deposition modeling® and related processes are the most widely used polymer rapid prototyping processes. For many applications, resolution, dimensional accuracy and surface roughness are among the most important properties in final parts. The influence of feedstock properties and system design on dimensional accuracy and resolution is reviewed. Thermal warping and shrinkage are often major sources of dimensional error in finished parts. This phenomenon is explored along with various approaches for evaluating dimensional accuracy. Product design parameters, in particular, slice height, strongly impact surface roughness. A geometric model for surface roughness is also reviewed.

This represents the first review of extrusion AM processes focusing on dimensional accuracy and surface roughness. Understanding and improving relationships between materials, design parameters and the ultimate properties of finished parts will be key to improving extrusion AM processes and expanding their applications.

This paper aims to present a survey concerning the accuracy of thermoplastic polymeric parts fabricated by additive manufacturing (AM). Based on the scientific literature, the aim is to provide an updated map of trends and gaps in this relevant research field. Several technologies and investigation methods are examined, thus giving an overview and analysis of the growing body of research.

Permutations of keywords, which concern materials, technologies and the accuracy of thermoplastic polymeric parts fabricated by AM, are used for a systematic search in peer-review databases. The selected articles are screened and ranked to identify those that are more relevant. A bibliometric analysis is performed based on investigated materials and applied technologies of published papers. Finally, each paper is categorised and discussed by considering the implemented research methods.

The interest in the accuracy of additively manufactured thermoplastics is increasing. The principal sources of inaccuracies are those shrinkages occurring during part solidification. The analysis of the research methods shows a predominance of empirical approaches. Due to the experimental context, those achievements have consequently limited applicability. Analytical and numerical models, which generally require huge computational costs when applied to complex products, are also numerous and are investigated in detail. Several articles deal with artificial intelligence tools and are gaining more and more attention.

The cross-technology survey on the accuracy issue highlights the common critical aspects of thermoplastics transformed by AM. An updated map of the recent research literature is achieved. The analysis shows the advantages and limitations of different research methods in this field, providing an overview of research trends and gaps.

The usage of additive manufacturing (AM) technology in industries has reached up to 50 per cent as prototype or end-product. However, for AM products to be directly used as final products, AM product should be produced through advanced quality control process, which has a capability to be able to prove and reach their desire repeatability, reproducibility, reliability and preciseness. Therefore, there is a need to review quality-related research in terms of AM technology and guide AM industry in the future direction of AM development.

This paper overviews research progress regarding the QC in AM technology. The focus of the study is on manufacturing quality issues and needs that are to be developed and optimized, and further suggests ideas and directions toward the quality improvement for future AM technology. This paper is organized as follows. Section 2 starts by conducting a comprehensive review of the literature studies on progress of quality control, issues and challenges regarding quality improvement in seven different AM techniques. Next, Section 3 provides classification of the research findings, and lastly, Section 4 discusses the challenges and future trends.

This paper presents a review on quality control in seven different techniques in AM technology and provides detailed discussions in each quality process stage. Most of the AM techniques have a trend using in-situ sensors and cameras to acquire process data for real-time monitoring and quality analysis. Procedures such as extrusion-based processes (EBP) have further advanced in data analytics and predictive algorithms-based research regarding mechanical properties and optimal printing parameters. Moreover, compared to others, the material jetting progresses technique has advanced in a system integrated with closed-feedback loop, machine vision and image processing to minimize quality issues during printing process.

This paper is limited to reviewing of only seven techniques of AM technology, which includes photopolymer vat processes, material jetting processes, binder jetting processes, extrusion-based processes, powder bed fusion processes, directed energy deposition processes and sheet lamination processes. This paper would impact on the improvement of quality control in AM industries such as industrial, automotive, medical, aerospace and military production.

Additive manufacturing technology, in terms of quality control has yet to be reviewed.

The purpose of this paper is to fabricate pre-existing geometries of the stents using solvent cast 3D printing (SC3P) and encapsulation of each stent with heparin drug by using aminolysis reaction.

The iron pentacarbonyl powder and poly-ɛ-caprolactone blend (PCIP) were used to print stent designs of Art18z, Palmaz-Schatz and Abbott Bvs1.1. The properties of antithrombosis, anticoagulation and blood compatibility were introduced in the stents by conjugation of heparin drug via the aminolysis process. The aminolysis process was confirmed by energy dispersive X-ray spectroscopy and Fourier transform infrared spectroscopy due to presence of amide group and nitrogen peak in the respective analysis. Biological studies were performed to depict the cell viability, hemocompatibility and antithrombotic properties. Besides, mechanical behaviors were analyzed to study the behavior of the stents under radial compression load and bending load.

The amount of heparin immobilized on the Art18z, Palmaz-Schatz and Abbott Bvs1.1 stents were 255 ± 27, 222 ± 30 and 212 ± 13 µg, respectively. The cell viability studies using L929 fibroblast cells confirmed the cytocompatibility of the stents. The heparinized SC3P printed stents displayed excellent thrombo-resistance, anticoagulation properties and hemocompatibility as confirmed by blood coagulation analysis, platelet adhesion test and hemolysis analysis. Besides, mechanical behavior was found in context of the real-life stents. All these assessments confirmed that the developed stents have the potential to be used in the real environment of coronary arteries.

Various customized shaped biodegradable stents were fabricated using 3D printing technique and encapsulated with heparin drug using aminolysis process.

The purpose of this study is to develop a model for business to business salesperson performance (SP) with a service ecosystems perspective.

To achieve the research aims, classical grounded theory was used. The data was gathered through in-depth interviews with 20 sales managers and main sales actors.

After coding and analyzing the data, salesperson institutional performance is introduced as a core category including three main dimensions of regulative, normative and cognitive-cultural performance. Multi-level factors determining SP are identified and performance results are introduced in a multi-level long term way. The sales actors, macro variables, actors’ orientations and sales method are introduced as circumstances, while salesperson stressors are presented as covariants deterring the fulfillment of salesperson’s activities.

This study focuses on the contributions of the salesperson in the alignment of institutional arrangements or the results of their being institutionalized, as well as determining the factors and variables affecting it.

The outbreak of Covid-19 increased the average time spent on social media (SM). This led to a transformation in how companies manage their digital marketing channels and created additional pressure for business-to-business (B2B) and family businesses, which tend to focus more on personal relationships with customers and stakeholders than on the implementation of digital marketing strategies on SM. The present research examines the case study of a Facebook advertising campaign created to promote the products and business values of an Italian family firm specialising in the production and commercialisation of biostimulants for agriculture.

The research aims to combine digital marketing avenues (i.e. a Facebook advertising campaign) with established psychological and behavioural theories, such as the dual process theories, by comparing the effects of two promotional videos (emotional vs functional).

The results suggest that emotional videos generate more passive behaviours, such as views, as well as active behaviours in the form of likes, comments and shares, while functional videos induce people to search for more information about the advertised products.

This is the first study to validate the role of Facebook advertising campaigns in developing an information-based approach to B2B family firms by testing the effectiveness of a targeted campaign comparing the impact of emotional and functional cues on increasing users' engagement while optimising the circulation of video content. The study helps to reduce the academic–practice gap by investigating the example of a fruitful integration between academic research and management practice.

Although the value of artificial intelligence (AI) has been acknowledged by companies, the literature shows challenges concerning AI-enabled business-to-business (B2B) marketing innovation, as well as the diversity of roles AI can play in this regard. Accordingly, this study investigates the approaches that AI can be used for enabling B2B marketing innovation.

Applying a bibliometric research method, this study systematically investigates the literature regarding AI-enabled B2B marketing. It synthesises state-of-the-art knowledge from 221 journal articles published between 1990 and 2021.

Apart from offering specific information regarding the most influential authors and most frequently cited articles, the study further categorises the use of AI for innovation in B2B marketing into five domains, identifying the main trends in the literature and suggesting directions for future research.

Through the five identified domains, practitioners can assess their current use of AI and identify their future needs in the relevant domains in order to make appropriate decisions on how to invest in AI. Thus, the research enables companies to realise their digital marketing innovation strategies through AI.

The research represents one of the first large-scale reviews of relevant literature on AI in B2B marketing by (1) obtaining and comparing the most influential works based on a series of analyses; (2) identifying five domains of research into how AI can be used for facilitating B2B marketing innovation and (3) classifying relevant articles into five different time periods in order to identify both past trends and future directions in this specific field.