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The purpose of this paper is to detail the development of a multimedia courseware that enhances the learning of rapid prototyping (RP) among professionals, senior year and graduate students.

The design and development of the multimedia courseware is based on a “visit a science museum” concept where each topic can be accessed depending on the interests or the needs of users. Factors that influence learning curve such as structure of information, application of visual and auditory components and human‐computer interface are addressed and discussed.

Instructions using multimedia significantly enhances the education process of RP technology. Methods to produce a good multimedia courseware have been introduced.

This paper describes the latest version of the multimedia courseware which is an accompaniment to the third edition of the book entitled Rapid Prototyping: Principles & Applications published in 2009.

Corruption was a serious problem in Singapore during the British colonial period and especially after the Japanese Occupation (February 1942–August 1945) mainly because of the lack of political will to curb it by the incumbent governments. In contrast, the People’s Action Party (PAP) government, which assumed office in June 1959 after winning the May 1959 general election, demonstrated its political will with the enactment of the Prevention of Corruption Act (POCA) in June 1960, which strengthened the capacity of the Corrupt Practices Investigation Bureau (CPIB) to combat corruption effectively. Indeed, Singapore’s success in curbing corruption is reflected in its consistently high scores on Transparency International’s Corruption Perceptions Index (CPI) from 1995 to 2012 as the least corrupt country in Asia. Singapore was ranked first with Denmark and New Zealand in the 2010 CPI with a score of 9.30. Similarly, Singapore has been ranked first in the Political and Economic Risk Consultancy (PERC) annual surveys on corruption from 1995 to 2013. Why has Singapore succeeded in minimizing the problem of corruption when many other Asian countries have failed to do so? What lessons can these countries learn from Singapore’s experience in combating corruption? This chapter addresses these two questions by first describing Singapore’s favorable policy context, followed by an identification of the major causes of corruption during the British colonial period and Japanese Occupation, and an evaluation of the PAP government’s anti-corruption strategy.

This study aims to investigate the production of scaffolds by selective laser sintering (SLS) using poly(vinyl alcohol) (PVA) polymer, for in vitro studies, a relatively new and growing area in which scaffolds could be used in the design of three-dimensional models for in vitro disease model or tissue equivalent for safety and effectiveness tests.

The influence of the SLS process parameters laser power, 26 W and 32 W, and number of laser scans, 1, 2, 4 and 6, on the surface microstructure of the samples and on the degree of crystallinity and chemical stability of PVA material, was investigated using powder with particle size of 20-320 µm. Laser sintered PVA samples were subjected to cell culture tests using osteoblastic cells derived from human osteosarcoma (SaOs-2).

The laser power has no significant influence on the microstructure of the laser-sintered samples, however the number of scans has a considerable influence on the sintering degree; the SLS process causes a decrease in the degree of crystallinity and changes the chemical structure of the as-received PVA, especially when using higher laser power and more number of scans. Preliminary in vitro cell culture tests show that the laser-sintered PVA material is biocompatible with SaOs-2 cells.

SLS offers good potential for the fabrication of scaffolds and thus, may be applied as an alternative to conventional scaffold fabrication processes to overcome their limitations.

The international wealth of sociological literature on family policy has grown significantly during the past ten years not only in terms of the number of studies published but, more importantly, in terms of the scope of topics and the depth of analysis. One of the reasons for this concern with family policy is the steadily increasing number of social policy areas (such as health, savings, housing, transport, food supply, recreation and welfare, among others) found to affect either the family as a group or individuals as family members.

This paper aims to estimate the required insertion force and to analyze the influence of damping in a compliantly supported chamfered peg-in-hole assembly under dynamic conditions.

A mathematical model of the insertion process, including damping coefficient and stiffness of the compliance, insertion speed, mass, inertia and friction coefficient, has been developed. Computer aided design (CAD) model of the peg-in-hole assembly environment with passive compliance is created. The dynamic insertion force of the modeled environment is analyzed using multibody dynamics numerical solver.

The damping property of the viscoelastic materials used in the passive compliances suppresses the vibration caused due to the impulses in the transition of the peg in hole. It also increases the insertion force required for the peg insertion at the initial stage.

As the search strategies are not considered in this work, it is assumed that the initial contact is ensured between the chamfer and the peg of the assembly. A constant insertion speed is maintained throughout the insertion. Otherwise, it could have been varied at different stages of the insertion for reducing the assembly time.

The developed assembly model can be used for predicting the insertion forces of a chamfered peg-in-hole assembly and for designing/selecting the compliance device for the required assembly environment.

The proposed insertion model has considered the damping and elastic property of the compliance material as a parallel arrangement of spring and dashpot. This approach aids in modeling an insertion process closer to real-time assembly process.

This paper aims to present an optimization algorithm combined with the impedance control strategy to optimize the robotic dual peg-in-hole assembly task, and to reduce the assembly time and smooth the contact forces during assembly process with a small number of experiments.

Support vector regression is used to predict the fitness of genes in evolutionary algorithm, which can reduce the number of real-world experiments. The control parameters of the impedance control strategy are defined as genes, and the assembly time is defined as the fitness of genes to evaluate the performance of the selected parameters.

The learning-based evolutionary algorithm is proposed to optimize the dual peg-in-hole assembly process only requiring little prior knowledge instead of modeling for the complex contact states. A virtual simulation and real-world experiments are implemented to demonstrate the effectiveness of the proposed algorithm.

The proposed algorithm is quite useful for the real-world industrial applications, especially the scenarios only allowing a small number of trials.

The paper provides a new solution for applying optimization techniques in real-world tasks. The learning component can solve the data efficiency of the model-free optimization algorithms.

This paper aims to develop a novel micro-ablation system to realise micrometric and well-defined hydrogel structures. To engineer a tissue it is necessary to evaluate several aspects, such as cell-cell and cell-substrate interactions, its micro-architecture and mechanical stimuli that act on it. For this reason, it is important to fabricate a substrate which presents a microtopology similar to natural tissue and has chemical and mechanical properties able to promote cell functions. In this paper, well-defined hydrogel structures embedding cells were microfabricated using a purposely developed technique, micro-laser ablation, based on a thulium laser. Its working parameters (laser power emission, stepper motor velocity) were optimised to produce shaded “serpentine” pattern on a hydrogel film.

In this study, initially, swelling/contraction tests on agarose and alginate hydrogel in different solutions of main components of cell culture medium were performed and were compared with the MECpH model. This comparison matched with good approximation experimental measurements. Once known how hydrogel changed its topology, microstructures with a well-defined topology were realised using a purposely developed micro-laser ablation system design. S5Y5 neuroblastoma cell lines were embedded in hydrogel matrix and the whole structure was ablated with a laser microfabrication system. The cells did not show damages due to mechanical stress present in the hydrogel matrix and to thermal increase induced by the laser beam.

The hydrogel structure is able to reproduce extracellular matrix. Initially, the hydrogel swelling/contraction in different solutions, containing the main components of the most common cell culture media, was analysed. This analysis is important to evaluate if cell culture environment could alter microtopology of realised structures. Then, the same topology was realised on hydrogel film embedding neuronal cells and the cells did not show damages due to mechanical stress present in the hydrogel matrix and to thermal increase induced by the laser beam. The interesting obtained results could be useful to realise well-defined microfabricated hydrogel structures embedding cells to guide tissue formation

The originality of this paper is the design and realisation of a 3D microfabrication system able to microfabricate hydrogel matrix embedding cells without inducing cell damage. The ease of use of this system and its potential modularity render this system a novel potential device for application in tissue engineering and regenerative medicine area.

The purpose of this research was an attempt to improve the applicability of the balance scorecard, in particular the customer perspective, in the hospitality industry. The objective of the study was to investigate a more structured customer-centric performance measurement framework customized for the hotel industry. Hence, this paper presents the “Customer Calculator” which had been developed based on the Customer Equity model proposed by Rust et al. (2000a). Qualitative examinations by interviewing hotel management were conducted to test the applicability of the customer-centric measurement framework. The customer scores facilitate hotel decision-makers who can pinpoint the important drivers of customer relations, which are in need of further action and improvement. The framework can also be employed by the stakeholders to assess hotel performance in general.

The purpose of this paper is to investigate theoretically the process of jamming in the peg‐hole type parts and to derive a mathematical model of jamming.

The mathematical model of the jamming of the peg‐hole type parts in assembly process was performed and its boundary conditions, which lead to jamming, defined.

The equation of the critical angles of declination for the peg, which leads to the peg‐hole jam, was derived. The boundary condition of the angles of declination and the depth of the peg insertion into the hole were defined.

A mathematical model is developed for rigid parts with a hole and for the peg clamped in the rigid assembly mechanisms. The research has not considered flexible deformations and stiffness of the assembly mechanisms, which result in the peg's declination in the assembly process.

The results are represented in the form of the peg's critical angles of declination and critical depth of insertion into the hole, which leads to jamming of the peg‐hole type parts to be assembled. On the basis of the obtained results, it is possible to formulate the tolerances of the declination angles for the assembly mechanisms, which clamp the peg‐type parts.

The proposed method calculating the critical angles of the peg's declination and critical depth of the peg's insertion into the hole for assembly of the peg‐hole type parts, enables one to increase the reliability of the assembly process in the manufacturing industry.