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The purpose of this paper is to report a study about the rapid prototyping method of dental glass‐ceramic restoration.

Dental glass‐ceramic restoration materials have excellent physical and chemical, mechanical, aesthetic and biocompatibility characteristics. However, casting methods adopted at present have complicated procedures and high costs; the forming qualities are especially difficult to control. These problems greatly restrict their clinical application and promotion. Therefore, a new forming process based on selective laser sintering (SLS) technology is proposed. First, dental glass‐ceramic is processed into fine powder through a special heat treatment process. Then, the dental restoration parts are manufactured using SLS without any moulds. In this paper, the effects of processing parameters including laser power, scan speed, scan spacing and preheating temperature on the relative density and mechanical properties of the sintered parts are studied.

The experimental results have shown that for the composite powder of epoxy resin binder E‐12 and K₂O‐Al₂O₃‐SiO₂ series of dental glass‐ceramics, when preheating temperature, layer thickness, laser power, scan speed and scan spacing are, respectively, 30∼35°C, 0.08 mm, 21 W, 1,800 mm/s and 0.10 mm/s, the relative densities of dental glass‐ceramic parts are relatively high; the mechanical properties and forming effect are excellent. The relative density and bending strength of SLS parts under the optimized processing parameters are 37.40 per cent and 2.08 MPa, respectively.

This study only concerns the preparation and SLS of the dental glass‐ceramic powders. Further investigations are planned to be conducted on post processing, such as binder decomposition, isostatic press and high temperature sintering.

This study will provide a theoretical and technical basis for dental glass‐ceramic restorations of SLS.

The purpose of this paper is twofold. First and most importantly, the paper aims to explain how Pilkington is able to revolutionize the flat glass industry. The modified design envelope model is applied to demonstrate the technological competence and especially strategic thinking concerning to understanding of the markets and positioning the product. Second, the paper demonstrates the entrepreneurship within a large‐scale manufacturing firm.

The paper applies a longitudinal, historical, and contextual approach. The paper uses multiple case study method and multiple data sources. This is done because creation of an innovation does not take place in vacuum, it is context bound.

The float glass fulfills the requirements of two industries: the plate and sheet glasses. Within both industries, short‐sighted competitors concentrate on technologies applicable only in other industry. Pilkington positions the float glass first clearly in the plate glass industry and after further development introduces the technology to sheet glass industry as a total surprise. Based on the case, the paper argues that positioning should be part of the corporate strategy.

In addition to complex systematic technologies, the example shows that the design envelope model is applicable also for simple non‐assembled products like flat glass. The model is useful for companies to build scenarios for responses if new unexpected innovations will be introduced in its own or related industries.

This paper offers a novel insight to the old but still viable case of dominant design. In addition, the thorough case description allows reader to go deeply into a classic example of process innovation.

The purpose of this paper is to outline the potential usage of ceramic engines in combination with other technologies as a possible propulsion contender for future aerospace applications.

The possibility of enabling novel propulsion systems in aerospace engineering is examined through a multilateral review study concerning ceramic engines and a proposed design approach. In view of the benefits and challenges of employing ceramic engines as possible candidates for the sustainable solutions of the future, a fundamental design proposal is presented for a conceptual generic unmanned air vehicle (GUAV).

The findings of this article identify a number of useful scenarios for future ceramic engine applications and considerations.

It is imperative to emphasize that this conceptual article solely sheds light on a limited number of key ideas associated with ceramic engines and their possible applications. Thus, many new areas may emerge and impact the application of ceramic engines in light of more in‐depth conceptual studies.

Implications of ceramic engine utilization in aeronautical applications may result in enhanced performance characteristics and less operational costs. Further implications could possibly be extended to various naval/automotive applications and new configurations of transportation vehicles.

The paper aims to generate an interest amongst younger individuals and environmental aware enthusiasts to consider ceramic engines for transportation applications to a greater extent than before.

The implementation of this particular conceptual design results in a synergistic ceramic engine combination with a hybrid airship design in novel aeronautical applications.

The purpose of this paper is to describe the use of copper‐substituted nickel manganite thick film and bulk ceramic superstrate on Ag thick film microstrip straight resonator (MSR), to modify its response and measure complex permittivity as a function of copper.

The glass frit free (fritless) copper‐substituted nickel manganite thick films were formulated on alumina substrate by screen printing technique from the powder synthesized by oxalic precursor method. A comparison has been made between the X band response of Ag thick film MSR due to perturbation of bulk and thick film Ni_(1−x)Cu_xMn₂O₄ (0≤x≤1) ceramic. The shift has been used to measure the permittivity of the ceramic. The dielectric constants obtained by superstrate technique on Ag thick film microstrip component are comparable to those obtained from theoretical calculations.

The resonance frequency of MSR shifts towards lower frequency due to the presence of Ni_(1−x)Cu_xMn₂O₄ (0≤x≤1) ceramic as superstrate. The dielectric constant of bulk and thick film match well with the theoretical values. The dielectric constant increases with copper concentration and shows reduction of power gain of MSR. The peak output (power gain) of MSR due to thick film NiMn₂O₄ increases by 10.19 per cent with decrease in bandwidth and increase in the quality factor with copper concentration.

The superstrate on Ag thick film straight resonator is an efficient tool capable of detecting the composition‐dependent changes in microwave properties of ceramic thick films. These Ni_(1−x)Cu_xMn₂O₄ ceramic being thermistor materials apart from modifying the response can also be used as power sensors providing cost‐effective miniaturization.

The purpose of this paper is to present a new ceramic suspension to fabricate complex ceramic parts by stereolithography (SL).

The process consists of preparation of aqueous ceramic suspensions, building ceramic parts, drying, subsequent binder removal, and sintering. Highly concentrated aqueous ceramic suspensions with a suitable viscosity are prepared, then a wet green ceramic part fabricated in a SL machine according to a 3D model is dried in polyethylene glycol. After binder removal sintering in a high temperature‐sintering furnace, a complex ceramic part is obtained.

The dispersant, volume fraction of ceramic powder and powder diameter could influence the viscosity of suspension. The cured depth is inversely proportional to the scanning speed of laser spot when the laser power keeps a constant and proportional to the concentration of monomer. The penetration depth and critical exposure are 0.27 mm and 231.2 mJ/cm² from the experimental result of the windowpanes method. A new support structure could prevent the deformation of ceramic part from the suspension and improve the quality of ceramic parts. A complex impeller is fabricated at last.

The dimensional and surface accuracy of ceramic SL should be further investigated.

This paper describes a new aqueous ceramic suspension to produce complex‐shaped ceramic parts by SL.

The purpose of this paper is to present a novel and effective fabricating method of 3D ceramic photonic crystals with diamond structure.

The reverse diamond‐structure resin molds are fabricated by stereolithography (SL), then ceramic slurry is prepared and injected into the molds under vacuum condition. Subsequently, ceramic photonic crystals are obtained after vacuum freeze‐drying and sintering.

The combination of SL, gel‐casting and freeze‐drying could be used to fabricate the 3D ceramic photonic crystals with diamond structure which have intact structure and minimal shrinkage. The samples have been tested and the experimental results indicate that their band gap is in the range of 10.14‐12.20 GHz, consistent with the simulation results.

The influence of fabrication process on the photonic band gap needs further study.

This paper presents a novel fabricating method of 3D diamond‐structure ceramic photonic crystals based on SL, gel‐casting and freeze‐drying. The method fabricates complex ceramic photonic crystals with high accuracy and helps further research in this field.

The purpose of this paper is to review the advancements made in the area of contemporary maintenance management individualisation, to identify the difficulties in strategy design and to document the implementation of such a strategy in a maintenance intense organisation.

A contemporary nine‐step framework for designing and implementing an individualised maintenance strategy is proposed. Individualising your maintenance strategy offers tangible benefits compared to the commercially available generic models, although the research highlights complexities in its conception and integration.

The proposed nine‐step framework was successfully integrated in a maintenance intense organisation and it had an immediate effect on all agreed performance indicators, from failure rates to overall maintenance costs.

The work to date in this field falls short of a complete solution and while the current research illustrates the viability of such an approach, much more work is required in the area of optimisation within each of the iterative nine steps.

This research is of interest to maintenance managers and front‐line maintenance practitioners. This framework is predicated upon practical experiences gathered by the authors within varying maintenance intense organisations and fully referenced published work by other authors.

Thick film technology is increasingly used in hybrid microelectronic circuits throughout the world. It is entering areas of electronics hitherto dominated by other technologies. Materials are the most important parameter in any technological development. A single material can generate several technologies (e.g., silicon). The role of a Materials Scientist, particularly in the case of Thick Film Materials, has to be very comprehensive. A ‘Vertical Integration System’ is followed in the study and development of thick film materials. This has helped in understanding the complex reactions taking place and in rectifying the defects formed during thick film processing. It has been amply rewarded during the development of several conducting and resistive materials and while carrying out the basic studies of other materials as thick films. Some future trends in this area have been suggested for adapting this fascinating thick film technology.

The purpose of this paper is to investigate the thermal fatigue endurance of two lead‐free solders used in composite solder joints consisting of plastic core solder balls (PCSB) and different solder materials, in order to assess their feasibility in low‐temperature cofired ceramic (LTCC)/printed wiring board (PWB) assemblies.

The characteristic lifetime of these joints was determined in a thermal cycling test (TCT) over a temperature range of −40‐125°C. Their failure mechanisms were analyzed after the TCT using scanning acoustic and optical microscopy, scanning electronic microscope, and field emission scanning electronic microscope investigation.

The results showed that four different failure mechanisms existed in the test assemblies cracking in the mixed ceramic/metallization zone; or a mixed transgranular/intergranular failure occurred at the low temperature extreme; whereas an intergranular failure within the solder matrix; or separation of the intermetallic layer and the solder matrix occurred at the high temperature extreme. Sn3Ag0.5Cu0.5In0.05Ni was more resistant to mixed transgranular/intergranular failure, but had poor adhesion with the Ag3Sn layer. On the other hand, cracking in the mixed ceramic/metallization zone typically existed in the joints with Sn2.5Ag0.8Cu0.5Sb solder, whereas the joints with Sn3Ag0.5Cu0.5In0.05Ni were practically free of these cracks. The characteristic lifetimes of both test joint configurations were at the same level (800‐1,000) compared with joints consisted of Sn4Ag0.5Cu solder and PCSB studied earlier.

The study investigated in detail the failure mechanisms of the Sn3Ag0.5Cu0.5In0.05Ni and Sn2.5Ag0.8Cu0.5Sb solders under harsh accelerated test conditions. It was proved that these solders behaved similarly to the ternary SnAgCu solders in these conditions and no improvement can be achieved by utilizing these solders in the non‐collpasible solder joints of LTCC/PWB assemblies.