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Shape memory polymer (SMP) is capable of recovering its original shape from a high degree of deformation by applying an external stimulus such as thermal energy. This research presents an integration of two commercial SMP materials (DiAPLEX and Tecoflex) and a material extrusion (ME) printer to fabricate SMP parts and specimens. The material properties such as Young’s modulus of the specimens was examined as a process output. Furthermore, stress-strain curve, strain recovery, instant shape-fixity ratio, long-term shape-fixity ratio and recovery ratio of SMP specimens during a thermo-mechanical cycle were investigated.

The ME fabrication settings for the SMP specimens were defined by implementing a design of experiments with temperature, velocity and layer height as process variables.

It was found, according to main effect and iteration plots, that fabrication parameters have an impact on Young’s modulus and exist minimum iteration among variables. In addition, Young’s modulus variation of DiAPLEX and Tecoflex specimens was mostly caused by velocity and layer height parameters, respectively. Moreover, results showed that SMP specimens were able to recover high levels of deformation.

This paper is a reference for process control and for rheological properties of SMP parts produced by ME fabrication process.

Shape memory polymers (SMPs) are classified as smart materials owing to their inherent stimulus-induced response. SMPs are capable of recovering partially or totally to its original shape after a high degree of deformation by external stimulus. The most used stimuli are thermal, light, magnetic field and electricity. This research aims to characterize the toughness property of thermo-responsive SMP specimens fabricated by the material extrusion (ME) process and to investigate the impact of ME parameters on specimen maximum load and load-displacement curves. Moreover, to investigate the recovery efficiency based on the initial and post toughness generated by the compact tension test.

A design of experiments with three parameters (temperature, velocity and layer height) defined the ME settings to fabricate the specimens. The ME raster orientation factor was also evaluated separately. In addition, one more specimen group assisted by a clamp during the recovery process was compared with a specimen control group. After fabrication, specimens were submitted to a thermo-mechanical cycle that encompasses a compact tension test and a thermo-recovery process. Comparison studies of load-displacement, toughness and recovery efficiency of the specimens were carried out to determine the optimized fabrication parameters.

It was found that ME parameters and raster orientation impacted the test results. Samples with the clamp support during recovery returned a higher toughness than samples without support. Finally, results showed that the shape memory effect can contribute with up to 43 per cent recovery efficiency in a first recovery and up to 23 per cent in a second recovery of damaged specimens.

This paper is a reference for toughness and recovery properties of SMP parts produced by the ME fabrication process.

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 study is to evaluate different 3D structures for humidity sensing that will enable the fabrication of complex geometries with high moisture sensitivity.

Humidity sensors based on alumina ceramics were fabricated using direct ink write (DIW) technique. Different engineered surface area, polymer binder ratio and post-processing treatment were considered to increase moisture sensitivity.

It was found that the binder ratio plays an important role in controlling the rheology of the paste during printing and determining the pore size after post-processing treatment. The sensibility of the fabricated humidity sensor was investigated by measuring its capacitance response toward relative humidity (RH) varying from 40% to 90% RH at 25°C. It is shown that using 3D lattice design, printed alumina humidity sensor could improve sensitivity up to 31.6 pF/RH%, over an order of magnitude higher than solid alumina.

Most of the alumina humidity sensors available are films in nature because of manufacturing difficulties, which limited its potential of higher sensitivity, and thus broader applications. In this paper, a novel 3D alumina humidity sensor was fabricated using DIW 3D printing technology.

Maintenance and its management has moved from being considered a “necessary evil” to being of strategic importance for most competitive organisations around the world. In terms of the identification and use of organisational-wide maintenance management models the picture is not clears from both a literature and practical perspective. The purpose of this paper is to shed light on the various models and their use in real-world applications, and in doing so, explores the gap between academic research and practice.

For this paper two comprehensive reviews of the literature were undertaken, first, to identify and categorise the various maintenance management models, and second, to determine the depth of empirical evidence for the popular models in real-world applications. Descriptive analysis of both the practical examples and empirical evidence rates (EER) for maintenance related journals is provided.

Within the literature 37 maintenance management models were identified and categorised. From these, three models were found to be popular: total productive maintenance (TPM), condition based maintenance, and reliability centred maintenance. While several thousand papers discussed these three models, only 82 articles were found to provide empirical evidence.

While providing a sound foundation for future research the outcomes are based solely on academic literature. Analysis of EER outside the field of maintenance is needed to make comparisons.

The paper offers practitioners a detailed contemporary overview of maintenance management models along with tabulated results of practical examples to present day organisations. Such practical-focused papers are very limited within academic literature.

With EER as low as 1.5 per cent for some journals this paper acts as a reminder to researchers that they have an obligation to society to spend taxpayer funded research on addressing social needs and real-world problems.

This paper makes a concerted attempt to link academic research with management and operational practitioners. While the paper is critical of the current academic imbalance between theory and practice, a number of suggestions to improve EER are offered in the conclusions.

New car dealerships play an integral role in the initial and on‐going relationship between the purchaser and vehicle manufacturer. Evidence, mostly anecdotal, suggests that the buying and servicing experience of the paying public in regards to new car dealerships is far from ideal. With continuous improvement systems such as total quality management (TQM) firmly embedded into the manufacturing and supply side of the car industry, questions still exist surrounding the level of quality being adopted by automotive dealerships. The purpose of this paper is to empirically investigate if a quality culture is being developed within the dealership network in South Australia by testing a number of key principles of TQM such as: the support and commitment from top management, customer focus and satisfaction, process management, and employee involvement.

A questionnaire survey was designed and all 105 new car dealerships in the greater Adelaide region were targeted. The service manager from each dealership was advised of the pending posted questionnaire and an excellent response rate of 66 percent was achieved.

Results indicated a reasonably high level of commitment to quality within dealerships, including the important success factors of TQM. Questions still remain about quality endorsement, the type of quality systems being used and the depth of penetration of quality at the ground level.

The limiting features of this study surround the descriptive nature of the data analysis and the fact that the study was only conducted in one major city in Australia.

The findings of this paper can give some implications for senior managers to consider when developing firm's policies.

Empirical studies on quality in automotive dealerships are very scarce in the literature. Therefore, this paper provides an insight into the quality culture of new car dealerships and examines if key TQM principles such as top management support, customer focus, process management, and employee involvement are in fact practised.

Despite increasing attentions to sustainable service supply chain management (SSSCM), a framework for performance evaluation of sustainable service only supply chain management (SSOSCM) is still missing. This paper tries to fill this gap and provides a novel conceptual framework.

The articles related to SSSCM are fetched from the databases of SCOPUS and Web of Science. Analysis of 174 articles identified by the systematic literature review is further carried out.

This research identifies the sustainable practices for service only supply chain (SOSC) as environmental management, social management, economic management, customer management, health, safety and risk management, technical sustainability, institutional sustainability, information and technology management as well as two performance measurement criteria as operational performance and organizational performance. This paper provides a novel conceptual framework for the performance evaluation of SSOSCM. The results call for future exploration in the following three broad directions-(1) customer's perception, involvement and their behaviour towards sustainability in SOSC context; (2) trade-off, incentive mechanism and multilevel evaluation for achieving sustainability in SOSC and (3) sustainability in SOSC from various point of views.

The managers can use the framework to assess the performance of the organization while researchers can explore the discussed research gaps.

This is the first paper that provides a novel conceptual framework for the performance evaluation of SSOSCM as well as potential future research directions.

This paper aims to examine the changing backdrop of the consumer market in relation to three-dimensional (3D) printing, especially in the context of Web infrastructure that connects consumers and producers with unprecedented diversity and scale and Web 2.0 user-created content in the material domain.

The paper presents a conceptual architecture and software platform that facilitates do-it-yourself reconfiguration of existing products incorporating 3D printing, mobile 3D sensor, augmented reality (AR) and Web technologies.

This work shows that prosumer reconfiguration of consumer products is the major paradigm in the era of democratized production. The results suggest that this approach may be used in the consumer market to meet consumer preferences for adopting innovations without redundant consumption.

Verification of the proposed conceptual approach is limited to the use of household consumer products. A critical mass of participants and product information are both necessary to achieve a sustainable ecosystem from the proposed platform. Intellectual property issues rely on the fair use of end-user production in this paper.

The proposed approach allows users to swap out consumer product parts or upgrade individual modules as innovations emerge, extending the lifecycles of consumer products and potentially reducing consumer waste.

There is a lack of work on facilitating the proliferation of practical 3D printing through prosumption in relation to existing consumer products. This paper’s scientific contribution involves how 3D printing affords social manufacturing and consumer-oriented presumption in conjunction with mobile 3D sensor, AR, and Web technologies.

The purpose of this paper is to present the results on a model for manufacturing under the constraints and conditions of mass customization environment.

The proposed model is based on manufacturing features and entails the concept of modular design. That is, manufacturing features are identified and analyzed in a way that enables the generation of what is called “manufacturing core”. Manufacturing cores are semi‐finished products that have certain manufacturing features. The core can be used to manufacture a range of products after conducting certain manufacturing processes. Manufacturing cores are generated through two phases of optimization. The first phase is known as product's manufacturing features analysis which includes starting features identification. The second phase is known as manufacturing cores formation that ends with generation of manufacturing cores.

The methodology is implemented on real products (flanges) as a case study. The proposed model for mass customization is compared at make‐to‐stock and make‐to‐order policies in terms of a burden which includes the time and the cost that are required to fulfil a production order. Applying the proposed model of mass customization entails the minimum total burden required.

When the number of generic and variant features increases, an automated feature‐recognition module or sub‐system is required to facilitate the extraction of manufacturing features.

The proposed methodology is used for design of customized product through the application of integrated design for modularity and mass customization approach for production.

The proposed methodology entails development of semi‐finished products based on manufacturing features that can be used for design and manufacturing of a range of products.

The purpose of this paper is to create a framework to provide a scalable maintenance program for unmanned aircraft systems (UAS) in order to choose the most suitable and feasible maintenance strategy in terms of reliability.

The paper opted for a reliability-centered maintenance-based approach to develop the framework using a UAS as the starting point of the research. A linear and user-friendly design of the methodology based on a Boolean flowchart was chosen in order to lead the analyst through the process avoiding as much as possible subjectivity decision-making issues. Finally, the framework was, on the component level, performed by a UAS company gathering feedback on its applicability.

An agile and structured decision-making framework for developing scalable maintenance program of UAS is provided. The proposed solution gives the opportunity to tailor the maintenance strategy to the technical characteristics, considering not only the single component but also situations and conditions in which the machine will operate.

Because of the chosen research approach, the framework is potentially applicable to every UAS. A first trial of the method was run on a multirotor vehicle equipped with eight electric brushless motors. Further studies focused on different UAS will be mandatory in order to obtain comparable and robust findings and a reliable approach.

This study offers a different scheme to elaborate a specific maintenance solution related to the characteristics of the system. It strives to remedy the drawbacks of the traditional approach for a manned aircraft not completely suitable for systems with such different functions, features and tasks. The authors believe that the method presented in this paper will provide a new selection tool for choosing maintenance actions based on the features of the UAS.

This paper provides a new and usable solution to include the maintenance actions in the management of pioneering products. In spite of the maintenance program representing an essential aspect to provide reliable assets, frameworks to create programs and to help manufacturers and users are still difficult to find or to apply to different UAS. This gap enhances the misunderstanding that the maintenance is not required or essential for the unmanned aircrafts management.