Business implications of manufacturing innovation : the experience of increasing automation in smaller to medium sized companies.

Despite the considerable potential of advanced manufacturing technologies (AMT) for improving the economic performance of many firms, a growing body of literature highlights many instances where realising this potential has proven to be a more difficult task than initially envisaged. Focussing upon the implementation of new manufacturing technologies in several smaller to medium sized enterprises (SME), the research examines the proposition that many of these problems can be attributed in part to inadequate consideration of the integrated nature of such technologies, where the effects of their implementation are not localised, but are felt throughout a business. The criteria for the economic evaluation of such technologies are seen as needing to reflect this, and the research develops an innovative methodology employing micro-computer based spreadsheets, to demonstrate how a series of financial models can be used to quantify the effects of new investments upon overall company performance. Case studies include: the development of a prototype machine based absorption costing system to assist in the evaluation of CNC machine tool purchases in a press making company; the economics and strategy of introducing a flexible manufacturing system for the production of ballscrews; and analysing the progressive introduction of computer based printing presses in a packaging and general print company. Complementary insights are also provided from discussion with the management of several other companies which have experienced technological change. The research was conducted as a collaborative CASE project in the Interdisciplinary Higher Degrees Scheme and was jointly funded by the SERC and Gaydon Technology Limited and later assisted by PE-Inbucon. The findings of the research shows that the introduction of new manufacturing technologies usually requires a fundamental rethink of the existing practices of a business. In particular, its implementation is seen as ideally needing to take place as part of a longer term business and manufacturing strategy, but that short term commercial pressures and limited resources often mean that firms experience difficulty in realising this. The use of a spreadsheet based methodology is shown to be of considerable assistance in evaluating new investments, and is seen as being the limit of sophistication that a smaller business is willing to employ. Several points for effective modelling practice are also given, together with an outline of the context in which a modelling approach is most applicable.

Aspects of the design and control of manufacturing systems subject to demand uncertainty

The recent explosive growth in advanced manufacturing technology (AMT) and continued development of sophisticated information technologies (IT) is expected to have a profound effect on the way we design and operate manufacturing businesses. Furthermore, the escalating capital requirements associated with these developments have significantly increased the level of risk associated with initial design, ongoing development and operation. This dissertation has examined the integration of two key sub-elements of the Computer Integrated Manufacturing (CIM) system, namely the manufacturing facility and the production control system. This research has concentrated on the interactions between production control (MRP) and an AMT based production facility. The disappointing performance of such systems has been discussed in the context of a number of potential technological and performance incompatibilities between these two elements. It was argued that the design and selection of operating policies for both is the key to successful integration. Furthermore, policy decisions are shown to play an important role in matching the performance of the total system to the demands of the marketplace. It is demonstrated that a holistic approach to policy design must be adopted if successful integration is to be achieved. It is shown that the complexity of the issues resulting from such an approach required the formulation of a structured design methodology. Such a methodology was subsequently developed and discussed. This combined a first principles approach to the behaviour of system elements with the specification of a detailed holistic model for use in the policy design environment. The methodology aimed to make full use of the `low inertia' characteristics of AMT, whilst adopting a JIT configuration of MRP and re-coupling the total system to the market demands. This dissertation discussed the application of the methodology to an industrial case study and the subsequent design of operational policies. Consequently a novel approach to production control resulted. A central feature of which was a move toward reduced manual intervention in the MRP processing and scheduling logic with increased human involvement and motivation in the management of work-flow on the shopfloor. Experimental results indicated that significant performance advantages would result from the adoption of the recommended policy set.

Mixing performance evaluation of additive manufactured milli-scale reactors

The mixing performance of three passive milli-scale reactors with different geometries was investigated at different Reynolds numbers. The effects of design and operating characteristics such as mixing channel shape and volume flow rate were investigated. The main objective of this work was to demonstrate a process design method that uses on Computational Fluid Dynamics (CFD) for modeling and Additive Manufacturing (AM) technology for manufacture. The reactors were designed and simulated using SolidWorks and Fluent 15.0 software, respectively. Manufacturing of the devices was performed with an EOS M-series AM system. Step response experiments with distilled Millipore water and sodium hydroxide solution provided time-dependent concentration profiles. Villermaux-Dushman reaction experiments were also conducted for additional verification of CFD results and for mixing efficiency evaluation of the different geometries. Time-dependent concentration data and reaction evaluation showed that the performance of the AM-manufactured reactors matched the CFD results reasonably well. The proposed design method allows the implementation of new and innovative solutions, especially in the process design phase, for industrial scale reactor technologies. In addition, rapid implementation is another advantage due to the virtual flow design and due to the fast manufacturing which uses the same geometric file formats.

Technological talespinning : new media and higher education in the USA : an examination of technological determinism

This thesis examines the theory of technological determinism, which espouses the view that technological change drives social change, through an analysis of the impact of new media on higher education models in the United States of America. In so doing, it explores the impacts of new media technologies on higher education, in particular, and society in general. The thesis reviews the theoretical shape of the discourse surrounding new media technologies before narrowing in on utopian claims about the impact of new media technologies on education. It tests these claims through a specific case study of higher education in the USA. The study investigates whether 'new' media technologies (eg the Internet) are resulting in new forms of higher education in the USA and whether the blurring of information and entertainment technologies has caused a similar blurring in education and entertainment providers. It uses primary data gathered by the author in a series of interviews with key education, industry and media representatives in North America in 1997. Chapter 2 looks at the literature and history surrounding several topics central to the thesis - the discourses of technological determinism, the history of technology use and adoption in education, and impacts of new media technologies on education. Chapter 3 presents the findings of the American case study on the relationship between media and higher education and Chapter 4 concludes and synthesises the investigation.

Design for manufacturing : a review and case study

Design for Manufacturing (DFM) is a highly integral methodology in product development, starting from the concept development phase, with the aim of improving manufacturing productivity. It is used to reduce manufacturing costs in complex production environments, while maintaining product quality. While Design for Assembly (DFA) is focusing on elimination or combination of parts with other components, which in most cases relates to performing a function and manufacture operation in a simpler way, DFM is following a more holistic approach. Common consideration for DFM are standard components, manufacturing tool inventory and capability, materials compatibility with production process, part handling, logistics, tool wear and process optimization, quality control complexity or Poka-Yoke design. During DFM, the considerable background work required for the conceptual phase is compensated for by a shortening of later development phases. Current DFM projects normally apply an iterative step-by-step approach and eventually transfer to the developer team. The study is introducing a new, knowledge based approach to DFM, eliminating steps of DFM, and showing implications on the work process. Furthermore, a concurrent engineering process via transparent interface between the manufacturing engineering and product development systems is brought forward.

Dermal fibroblast infiltration of poly(ε-caprolactone) scaffolds fabricated by melt electrospinning in a direct writing mode

Melt electrospinning in a direct writing mode is a recent additive manufacturing approach to fabricate porous scaffolds for tissue engineering applications. In this study, we describe porous and cell-invasive poly (ε-caprolactone) scaffolds fabricated by combining melt electrospinning and a programmable x–y stage. Fibers were 7.5 ± 1.6 µm in diameter and separated by interfiber distances ranging from 8 to 133 µm, with an average of 46 ± 22 µm. Micro-computed tomography revealed that the resulting scaffolds had a highly porous (87%), three-dimensional structure. Due to the high porosity and interconnectivity of the scaffolds, a top-seeding method was adequate to achieve fibroblast penetration, with cells present throughout and underneath the scaffold. This was confirmed histologically, whereby a 3D fibroblast-scaffold construct with full cellular penetration was produced after 14 days in vitro. Immunohistochemistry was used to confirm the presence and even distribution of the key dermal extracellular matrix proteins, collagen type I and fibronectin. These results show that melt electrospinning in a direct writing mode can produce cell invasive scaffolds, using simple top-seeding approaches.

Fabrication and in vitro characterisation of bioactive glass composite scaffolds for bone regeneration

Here we fabricate and characterise bioactive composite scaffolds for bone tissue engineering applications. 45S5 Bioglass® (45S5) or strontium-substituted bioactive glass (SrBG) were incorporated into polycaprolactone (PCL) and fabricated into 3D bioactive composite scaffolds utilising additive manufacturing technology. We show that composite scaffolds (PCL/45S5 and PCL/SrBG) can be reproducibly manufactured with a scaffold morphology highly resembling that of PCL scaffolds. Additionally, micro-CT analysis reveals BG particles were homogeneously distributed throughout the scaffolds. Mechanical data suggested that PCL/45S5 and PCL/SrBG composite scaffolds have higher compressive Young’s modulus compared to PCL scaffolds at similar porosity (~75%). After 1 day in accelerated degradation conditions using 5M NaOH, PCL/SrBG, PCL/45S5 and PCL lost 48.6 ±3.8%, 12.1 ±1% and 1.6 ±1% of its original mass, respectively. In vitro studies were conducted using MC3T3 cells under normal and osteogenic conditions. All scaffolds were shown to be non-cytotoxic, and supported cell attachment and proliferation. Our results also indicate that the inclusion of bioactive glass (BG) promotes precipitation of calcium phosphate on the scaffold surfaces which leads to earlier cell differentiation and matrix mineralisation when compared to PCL scaffolds. However, as indicated by ALP activity, no significant difference in osteoblast differentiation was found between PCL/45S5 and PCL/SrBG scaffolds. These results suggest that PCL/45S5 and PCL/SrBG composite scaffold shows potential as a next generation bone scaffold.

Application of lean production to reducing operational waste in a tile manufacturing process

Roofing tile manufacturing is a mass production process with high operational and inventory wastes and costs. Due to huge operational costs, excessive inventory and wastes, and quality problems, roofing tile manufacturers are trying to implement lean manufacturing practice in their operations in order to remain competitive in an ncreasingly competitive global market. The aim of this research is to evaluate the possibility of reducing the operational and inventory costs of the tile manufacturing process through waste minimization. This paper analyses the current waste situation in a tile manufacturing process and develops current and future value stream mapping for such a process with a view to implementing lean principles in manufacturing. The focus of the approach is on cost reduction by eliminating non-value-added activities.

A methodology for effective implementation of lean strategies and its performance evaluation in manufacturing organizations

Purpose – The purpose of this paper is to develop an effective methodology for implementing lean manufacturing strategies and a leanness evaluation metric using continuous performance measurement (CPM). Design/methodology/approach – Based on five lean principles, a systematic lean implementation methodology for manufacturing organizations has been proposed. A simplified leanness evaluation metric consisting of both efficiency and effectiveness attributes of manufacturing performance has been developed for continuous evaluation of lean implementation. A case study to validate the proposed methodology has been conducted and proposed CPM metric has been used to assess the manufacturing leanness. Findings – Proposed methodology is able to systematically identify manufacturing wastes, select appropriate lean tools, identify relevant performance indicators, achieve significant performance improvement and establish lean culture in the organization. Continuous performance measurement matrices in terms of efficiency and effectiveness are proved to be appropriate methods for continuous evaluation of lean performance. Research limitations/implications – Effectiveness of the method developed has been demonstrated by applying it in a real life assembly process. However, more tests/applications will be necessary to generalize the findings. Practical implications – Results show that applying the methods developed, managers can successfully identify and remove manufacturing wastes from their production processes. By improving process efficiency, they can optimize their resource allocations. Manufacturers now have a validated step by step methodology for successfully implementing lean strategies. Originality/value – According to the authors’ best knowledge, this is the first known study that proposed a systematic lean implementation methodology based on lean principles and continuous improvement techniques. Evaluation of performance improvement by lean strategies is a critical issue. This study develops a simplified leanness evaluation metric considering both efficiency and effectiveness attributes and integrates it with the lean implementation methodology.

Optimization approaches for the design of additively manufactured scaffolds

Scaffolds play a pivotal role in tissue engineering, promoting the synthesis of neo extra-cellular matrix (ECM), and providing temporary mechanical support for the cells during tissue regeneration. Advances introduced by additive manufacturing techniques have significantly improved the ability to regulate scaffold architecture, enhancing the control over scaffold shape and porosity. Thus, considerable research efforts have been devoted to the fabrication of 3D porous scaffolds with optimized micro-architectural features. This chapter gives an overview of the methods for the design of additively manufactured scaffolds and their applicability in tissue engineering (TE). Along with a survey of the state of the art, the Authors will also present a recently developed method, called Load-Adaptive Scaffold Architecturing (LASA), which returns scaffold architectures optimized for given applied mechanical loads systems, once the specific stress distribution is evaluated through Finite Element Analysis (FEA).

Transformation in educational practices through STEM

The need for strong science, technology and innovation linkages between Higher Education Institutions (HEIs) and industries is a pivotal point for middle-income countries in their endeavor to enhance human capital in socioeconomic development. Currently, the University-Industry partnerships are at an infant stage in Sri Lankan higher education context. Technological maturity and effective communication skills are contributing factors for an efficient graduate profile. Also, expanding internship programs in particular for STEM disciplines provide work experience to students that would strengthen the relevance of higher education programs. This study reports historical overviews and current trends in STEM education in Sri Lanka. Emphasis will be drawn to recent technological and higher education curricular reforms. Data from the last 10 years were extracted from the higher education sector and Ministry of Higher Education Policy portfolios. Associations and trend analysis of the sector growth were compared with STEM existence, merger and predicted augmentations. Results were depicted and summarised based on STEM streams and disciplines. It was observed that the trend of STEM augmentation in the Sri Lankan Higher Education context is growing at a slow but steady pace. Further analysis with other sectors in particular, Industry information, would be useful and a worthwhile exercise.

Does usability engineering matters for STEM education?

Technological maturity and the exponential growth of digital applications are contributing to lifestyle changes worldwide. Consequently, learning and teaching is demanding more effective sociotechnical interactions involving emerging technologies, as opposed to traditional, conventional face-to-face learning and teaching approaches. In this context, usability engineering is making significant contributions for improving computer and distance-based learning, both for learners and instructors, which have often been ignored when designing online learning and teaching applications. Usability testing is a central part of the human centered learning approach for developing sustainable STEM education from the socio-technological perspective. Our experiences with usability engineering and the impact of teaching low-cost rapid usability testing methods on knowledge translation from undergraduate to graduate courses to real-world practice (i.e. getting the methods out there in real use) are diverse and multi-modal. Our sample space has been hundreds of trained students who have learned how to do effective usability engineering in real-world situations at higher levels of realism (i.e. fidelity) and at a much lower cost than using traditional fixed usability labs. Furthermore, this low-cost rapid approach to usability engineering has been adopted by many of our graduates who are now managers, CIOs etc and who are using the methods routinely in their organizations in real world applications and scenarios. This knowledge has been used to improve design and implementation of a wide range of applications, including applications designed for teaching and learning.

Characterisation of the micro-architecture of direct writing melt electrospun tissue engineering scaffolds using diffusion tensor and computed tomography microimaging

This article describes the first steps toward comprehensive characterization of molecular transport within scaffolds for tissue engineering. The scaffolds were fabricated using a novel melt electrospinning technique capable of constructing 3D lattices of layered polymer fibers with well - defined internal microarchitectures. The general morphology and structure order was then determined using T 2 - weighted magnetic resonance imaging and X - ray microcomputed tomography. Diffusion tensor microimaging was used to measure the time - dependent diffusivity and diffusion anisotropy within the scaffolds. The measured diffusion tensors were anisotropic and consistent with the cross - hatched geometry of the scaffolds: diffusion was least restricted in the direction perpendicular to the fiber layers. The results demonstrate that the cross - hatched scaffold structure preferentially promotes molecular transport vertically through the layers ( z - axis), with more restricted diffusion in the directions of the fiber layers ( x – y plane). Diffusivity in the x – y plane was observed to be invariant to the fiber thickness. The characteristic pore size of the fiber scaffolds can be probed by sampling the diffusion tensor at multiple diffusion times. Prospective application of diffusion tensor imaging for the real - time monitoring of tissue maturation and nutrient transport pathways within tissue engineering scaffolds is discussed.

Improved fabrication of melt electrospun tissue engineering scaffolds using direct writing and advanced electric field control

Direct writing melt electrospinning is an additive manufacturing technique capable of the layer-by-layer fabrication of highly ordered 3d tissue engineering scaffolds from micron-diameter fibres. The utility of these scaffolds, however, is limited by the maximum achievable height of controlled fibre deposition, beyond which the structure becomes increasingly disordered. A source of this disorder is charge build-up on the deposited polymer producing unwanted coulombic forces. In this study we introduce a novel melt electrospinning platform with dual voltage power supplies to reduce undesirable charge effects and improve fibre deposition control. We produced and characterised several 90° cross-hatched fibre scaffolds using a range of needle/collector plate voltages. Fibre thickness was found to be sensitive only to overall potential and invariant to specific tip/collector voltage. We also produced ordered scaffolds up to 200 layers thick (fibre spacing 1 mm, diameter 40 μm) and characterised structure in terms of three distinct zones; ordered, semi-ordered and disordered. Our in vitro analysis indicates successful cell attachment and distribution throughout the scaffolds, with little evidence of cell death after seven days. This study demonstrates the importance of electrostatic control for reducing destabilising polymer charge effects and enabling the fabrication of morphologically suitable scaffolds for tissue engineering.