Understanding asymmetries in macroeconomic aggregates : the case of Singapore

For robust policymaking and econometric modelling, it is essential to know whether macroeconomic aggregates contain asymmetric behaviour. The aim of this note is to investigate asymmetries in Singapore's macroeconomic aggregates using the Randles et al. (1980) Triples test. We examine both deepness and steepness asymmetries, and find that for Consumer Price Index (CPI) and unemployment rate there is evidence for deepness asymmetry. On the basis of this finding, we caution policymakers.

Thermal degradation kinetics and morphology of natural rubber/silica nanocomposites

A novel natural rubber/silica (NR/SiO₂) nanocomposite with a SiO₂ loading of 4 wt% is developed by incorporating latex compounding with self-assembly techniques. The SiO₂ nanoparticles are homogenouslydistributed throughout the NR matrix as spherical nano-clusters with an average size of 75 nm. In comparison with the host NR, the thermal resistance of the nanocomposite is significantly improved. The degradation temperatures (T), reaction activation energy(E), and reaction order (n) of the nanocomposite are markedly higher than those of the pure NR, due to significant retardant effect of the SiO₂ nanoparticles.

Self-assembled natural rubber/silica nanocomposites : its preparation and characterization

A novel natural rubber/silica (NR/SiO2) nanocomposite is developed by combining self-assembly and latex-compounding techniques. The results show that the SiO2 nanoparticles are homogenously distributed throughout NR matrix as nano-clusters with an average size ranged from 60 to 150 nm when the SiO2 loading is less than 6.5 wt%. At low SiO2 contents (less-than-or-equals, slant4.0 wt%), the NR latex (NRL) and SiO2 particles are assembled as a core-shell structure by employing poly (diallyldimethylammonium chloride) (PDDA) as an inter-medium, and only primary aggregations of SiO2 are observed. When more SiO2 is loaded, secondary aggregations of SiO2 nanoparticles are gradually generated, and the size of SiO2 cluster dramatically increases. The thermal/thermooxidative resistance and mechanical properties of NR/SiO2 nanocomposites are compared to the NR host. The nanocomposites, particularly when the SiO2 nanoparticles are uniformly dispersed, possess significantly enhanced thermal resistance and mechanical properties, which are strongly depended on the morphology of nanocomposites. The NR/SiO2 has great potential to manufacture medical protective products with high performances.

The future of distance education : reformed, scrapped or recycled

A mass of under-educated people, an expanding population, major global crises and an expanding knowledge economy all combine to sustain a massive demand for basic, further, higher, continuing and lifelong education.This demand cannot be met solely in the world’s classrooms; even if there were enough classrooms, many people will be unwilling or unable to attend them to learn. In this sense, distance education is essential for the future, but the fluidity around educational terms and practices means that it is also quite possible that ‘distance education’—the term and its history—will be towed to the scrap yard for many of its useful parts to be recycled. This chapter considers three key elements of distance education—technology, students and educational institutions—and the educational possibilities that surround them by reflection on past and present changes. The future of distance education is intimately connected to broader social, economic and cultural changes. These changes are strongly influenced by the ‘disruptive’ technologies, demographic transformations in the nature of distance learners and the pressures of global techno-capitalism on educational institutions.