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Ceramics powder of BaCe 0.95 Yb 0.05 O 2.975 was successfully prepared by sol-gel method. Thermogravimetric analysis showed that the decomposition of the dried powder was completed at 1,000°C. Three strongly exothermic peaks observed in differential thermogravimetric signal indicated three major stages of weight loss in the sample. The high crystallinity of sample with orthorhombic structure was confirmed by X-ray diffraction. The loose particles size obtained from scanning electron microscope was in the range of 65-100 nm, which is almost in the same range as that observed in particle size distribution. The sample showed a dc conductivity of~1.3×10 −4 S cm −1 at 650°C and the activation energy, E a , was found to be 1.4 eV. Result of chemical stability test showed that the compound was unstable in atmosphere containing pure carbon dioxide.

A sol-gel route was used to prepare Yb-doped BaCeO 3 at the relatively low temperature of 1,100°C. At this calcination temperature, the carbonate residues were completely decomposed and the high crystallinity of Ybdoped BaCeO 3 powders with orthorhombic structure was obtained. The loose particles in nanosized range was observed from scanning electron micrographs but agglomerates with size ranging from 200 to 500 nm seem to dominate the bulk powder. Density of the pellet sintered at 1,400°C for 24 h was about 95% of the theoretical density. Morphology of the fractured pellet revealed that the diameter of grains was between 1 and 3 μm. AC electrical conductivity of the sample in wet air was carried out using impedance spectroscopy in the range of 1 Hz to 10 MHz. At 300°C, it was found that at high frequencies the imaginary values of the impedance were positive. The effect was attributed to the presence of an inductive element in the experimental setup.

Abstract. Modular coordination (MC) is recognized as a tool towards rationalization and industrialization. The implementation of MC concept in the design stage may improve the constructability and construction time. However, the implementation of MC in Industrialized Building System (IBS) implementation is still low compare to other developed countries such as the United Kingdom, Sweden and Japan. This paper examined the interrelationship between motivational factors of stakeholders in adopting MC concept using Interpretative Structural Modeling (ISM). Questionnaire survey was engaged in this study to identify significant motivational factors. Then, semi-structure interviews were used to collect qualitative data. ISM was adopted to build relationship between factors and develop an initial model to promote the adoption of MC in IBS construction. Seven (7) significant motivational factors were identified in this research namely 1) 'stakeholder's commitment', 2) 'reduce site disruption', 3) 'increase productivity', 4) 'high skilled workers', 5) 'site sustainability (environment, economy and social benefits)' 6) 'standardization' and 7) 'enabling 'open building' concept'. The result using Matrice d'Impacts Croises Multiplication Applique an Clasment (MICMAC) shows that there are three factors can be categorized as Independent / Driving Factors namely 'stakeholder's commitment', 'standardization' and 'enabling "open building" concept'. These factors should be explored in details to enhance the adoption of IBS in Malaysia. The findings provide a very good platform for a further research in formulating an efficient solution to promote MC concept adoption among the stakeholders. This scenario will improve the deliverables of IBS construction and eliminate negative perception in its implementation.