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Fabricating functionally graded scaffolds to mimic the complex spatial distributions of the composition, micro-structure and functionality of native tissues will be one of the key objectives for future tissue engineering research. This study aims to create a scaffold to mimic functionally-graded tissue using a hybrid process, which incorporated electrospun polycaprolactone (PCL) and electrosprayed hydroxyapatite (HA) in a simple pathway.

The PCL and HA were dispensed simultaneously from different positions to form a layer on a rotational mandrel, and a gradient construct was achieved by adjusting dispensing rates of both materials.

The morphology of scaffolds changed gradually from one layer to another layer with the change of the dispensing conditions of the two materials. The elemental distribution analysis revealed that C/Ca ratio linearly increased with certain dispensing rate ratio of PCL:HA. In addition, the thickness, mechanical properties (i.e. ultimate tensile stress and Young’s modulus), surface roughness and water contact angle of each layer changed accordingly with the variation of dispensing rate of PCL and HA, and the diameter distributions of PCL fibres and HA particles did not vary significantly.

This study showed the hybrid process has the potential to be used in fabrication of scaffold with functionally graded structure for tissue engineering applications, especially for mimicking the nature of the native 3D tendon–bone interface.

Fused deposition modelling (FDM) is one of the most popular additive manufacturing processes, and is widely used for prototyping and fabricating low-cost customized parts. Current FDM machines have limited techniques to monitor process conditions to minimize process errors, such as nozzle clogging. Nozzle clogging is one of the most significant process errors in current FDM machines, and may cause serious consequences such as print failure. This paper aims to present a physics-based dynamic model suitable for monitoring nozzle clogging in FDM machines.

Liquefier mount of an FDM extruder is analysed as a beam excited by a uniform loading distributed over a partial length. Boundary conditions and applied loads for a direct-type FDM extruder are identified and discussed. Simulation of nozzle clogging was performed by using nozzles of different diameters from 0.5 to 0.2 mm, in step change of 0.1 mm. Sets of experiments were carried out by measuring vibrations of the liquefier block mount during FDM extrusion.

The mount of a liquefier block in an FDM extruder can be used to place a vibration sensor to monitor process errors such as nozzle clogging. Liquefier block mount’s transverse vibration amplitudes increase non-linearly when nozzle starts to block.

The proposed model can be effectively used for monitoring nozzle clogging in FDM machines, as it is based on the physics relating the FDM process parameters and the nozzle blockage.

The novelty of this paper is the unique method of modelling the FDM process dynamics that can be used for monitoring nozzle clogging.

Product configuration is considered as one of the most successful applications of knowledge‐based approaches in the past decade. Knowledge‐based configurations can be classified into three different approaches, namely, rule‐based, model‐based and case‐based approaches. Past research has mainly focused on the development of reasoning techniques for mapping requirements to configurations. Despite the success of certain conventional approaches, the acquisition of configuration knowledge is usually done manually. This paper aims to explore fundamental issues in product configuration system, and propose a novel approach based on data mining techniques to automatically discover configuration knowledge in constraint‐based configurations.

Given a set of product data comprising product requirements specification and configuration information, the paper adopted an association rule mining algorithm to discover useful patterns between requirement specification and product components, as well as the correlation among product components. A configuration was developed which takes XML‐based requirement specification as input and bases on a constraint knowledge base to produce product configuration as output consisting of a list of selected components and the structure and topology of the product. Three modules are developed, namely product data modelling, configuration knowledge generation and product configuration generation module. The proposed approach is implemented in the configuration knowledge generation module. The configuration generation module realizes a resolution of constraint satisfaction problem to generate the output configuration.

The significance and effectiveness of the proposed approach is demonstrated by its incorporation in our configuration system prototype. A case study was conducted and experimental results show that the approach is promising in finding constraints with given sufficient data.

Novel knowledge generation approach is proposed to assist constraint generation for Constraint‐based product configuration system.

In today's globalized economy, distributed collaboration in engineering is important. Participants of engineering teams, with their specific knowledge situated in different locations, must be able to work together as efficiently and as comfortably as possible to provide an optimum contribution to product development. This paper aims to improve the effectiveness of internet based communication.

Analysis of the current situation was carried out from different perspectives. First, an in‐depth state‐of‐the‐art study of existing hardware and software concepts was done. Second, these tools were evaluated by collaboration experiments. Finally, a concept for improved internet collaboration was elaborated and implemented.

The main technical method used in this concept is a data overlay which allows different interactive information levels to be mapped on top of a video stream. In addition, eye‐to‐eye video conferencing hardware and a perceptive user interactions system are combined in an integrated system.

An application framework was developed, which integrates the different technologies. Using this framework, three application scenarios were implemented and tested. One focusing on brainstorming using the metaplan‐technique, second is used to build function‐structures and the third allows engineers to plan a plant on 2D, while it is shown in 3D.

Participants can now interact with digital information objects, yet being able to directly face their colleague and discuss simultaneously with the use of gestures such as pointing on objects. Users are free to adjust dynamically their focus between digital information and video by choosing transparency levels.

The purpose of this article is to introduce an innovative methodology to support manufacturing changes in the foundation of flexibility measurements and evaluations and to integrate this in the companies' internal as well as companies' cross‐organisational processes of change management.

The approach consists of two phases: first, a consistent systematics for the production systems flexibility evaluation is presented; second, the change processes are analysed and quantified flexibility indicators are integrated to support the decision – making process.

The application of the methodology in manufacturing environments has demonstrated that consideration of flexibility in the production and its integration into the manufacturing change processes has a great potential.

The originality of this work is in the integrated approach to consider flexibility as support for the change management. In particular the integration of quantified flexibility measurements into the change processes comes out to be the real innovation of the project.

The purpose of this paper is to present an information model (ontology) for design‐for‐manufacturing (DFM) problems, where parts are to be manufactured using an additive manufacturing process. DFM problem formulation is often challenging since the formulation step requires both design and manufacturing process knowledge. The ontology also captures some relationships that model how that manufacturing knowledge applies to part designs. The ontology is implemented and serves as a repository of DFM problems that are available for reuse.

The ontology is encoded using a description logic (DL) known as ALE. Using this ontology, a designer can retrieve archived DFM problems that are similar to a problem being formulated. DLs are a subset of first‐order logic that have been used for information modeling in several application areas, including engineering information management. They are used typically to construct classification hierarchies that can be efficiently searched.

The paper demonstrates that the DL model is correct by showing that the classification hierarchies that are computed match our DFM ontology. Retrieval of DFM problems is demonstrated using a prototype implementation of our ontology. Examples are taken from the area of design for manufacture using the stereolithography process.

The domain of the ontology is limited to additive manufacturing processes. Only DFM problems related to the determination of design parameters (e.g. dimensions) were within the scope of this work.

No ontology for DFM problems has been presented previously. Implementation of the ontology using DL is also original.

This paper aims to present a novel rapid prototyping (RP) fabrication methods and preliminary characterization for chitosan scaffolds.

A desktop rapid prototyping robot dispensing (RPBOD) system has been developed to fabricate scaffolds for tissue engineering (TE) applications. The system is a computer‐controlled four‐axis machine with a multiple‐dispenser head. Neutralization of the acetic acid by the sodium hydroxide results in a precipitate to form a gel‐like chitosan strand. The scaffold properties were characterized by scanning electron microscopy, porosity calculation and compression test. An example of fabrication of a freeform hydrogel scaffold is demonstrated. The required geometric data for the freeform scaffold were obtained from CT‐scan images and the dispensing path control data were converted form its volume model. The applications of the scaffolds are discussed based on its potential for TE.

It is shown that the RPBOD system can be interfaced with imaging techniques and computational modeling to produce scaffolds which can be customized in overall size and shape allowing tissue‐engineered grafts to be tailored to specific applications or even for individual patients.

Important challenges for further research are the incorporation of growth factors, as well as cell seeding into the 3D dispensing plotting materials. Improvements regarding the mechanical properties of the scaffolds are also necessary.

One of the important aspects of TE is the design scaffolds. For customized TE, it is essential to be able to fabricate 3D scaffolds of various geometric shapes, in order to repair tissue defects. RP or solid free‐form fabrication techniques hold great promise for designing 3D customized scaffolds; yet traditional cell‐seeding techniques may not provide enough cell mass for larger constructs. This paper presents a novel attempt to fabricate 3D scaffolds, using hydrogels which in the future can be combined with cells.

The purpose of this paper is to propose a “Fit” manufacturing paradigm for industry so that manufacturing companies can become economically sustainable and can operate effectively in a global competitive market. The proposed Fit paradigm is aimed at providing a new manufacturing management perspective to both academics and industrialists.

The Fit paradigm is developed and proposed as a new manufacturing management strategy towards creating economically sustainable manufacturing organisations. Fit is a theoretical development using the principles of existing manufacturing paradigms along with new and innovative management concepts to create a sustainable approach to manufacturing.

Manufacturing strategies such as lean and agility allow companies to deliver bottom‐line savings in production terms although their effectiveness depends upon the volume and demand profile of their products. The trend towards mass customisation requires companies to provide personalised products and services at mass production prices. This now places a further burden on companies and therefore a holistic manufacturing framework must be developed in order to ensure that the factory of the future is able to meet this new demand. This paper proposes a fit manufacturing paradigm which integrates the manufacturing efficiencies achieved through lean and agility with the need to break into new markets through effective marketing and product innovation strategies to achieve long term economic sustainability. The small scale application of the approach in a case company shows that the initial results to be positive when measured against a fit index which is developed within this paper.

The development of a fit paradigm aimed at tackling directly the issues of economic sustainability is proposed and is considered by the authors as one of a kind. Fit will also provide a framework for the implementation of sustainable manufacturing operations within organisations.

In recent years, business companies are challenged with various difficulties in connection to human resources (HR), for example, adapting to one’s sentiments, managing debates, developing collaboration, affecting leadership, addressing motives, interpersonal susceptibility, dealing with capabilities and also individual emotional intelligence (EI) or inward characteristics (e.g. moral qualities). Expanding on and reaching out earlier and ongoing work, the scope of this research is to experimentally look at the connection between the components of EI and ethics in contemporary organizations and their resulting impact on employees’ motives and performance. A quantitative method was utilized, and an entirety of 386 questionnaires was collected from three diverse high-tech new businesses based in Greece and analyzed with SPSS programing. For triangulation reasons, auxiliary information from the organizations’ sites were gathered and a meeting with each organization’s executive of the HR division was held. The outcomes propose that ethical values add to motives and thus employee motives add to employee performance. Helpful administrative ramifications resulted from this research.