Explaining the location decision of moving firms using their mobility profile and the accessibility of locations

This paper describes the research approach and first empirical results of the estimation of discrete choice models that describe the location decision of moving firms. The model is based on random utility theory and features systematic choice sets to account for the choice context at the highest level of spatial detail (address-level). Firms are analysed categorised to their mobility profile. These mobility profiles are homogenous groups of firms with similar mobility characteristics that are a priori assumed. The models are tested on an extensive revealed preference dataset with firm migration observations in South Holland. To avoid correlations between variables a variety of composed accessibility variables have been constructed that describe the distances to the physical infrastructure or that are an aggregated form of potential accessibility. The location attributes of alternatives have been completed with the business environment type and the rental level. The results are first of all valuable for the development of a simulation model for firm location but the empirical results also yields insight into the spatial behaviour and location preference of firms. Although further research is necessary, the presented addresses some challenges in modelling the spatial behaviours of firms in an urban environment. Therefore the presented approach holds seems valuable for the development of a simulation model for location decisions of moving firms and offers good possibilities for future research.

The Effects Of Triphenylphosphate and Recorcinolbis(Diphenylphosphate) on the Thermal Degradation Of Polycarbonate in Air

The thermal degradation of polycarbonate/triphenylphosphate (PC/TPP) and PC/resocinolbis(diphenylphosphate) (PC/RDP) in air has been studied using TGA/FTIR and GC/MS. In PC/phosphate blends, the phosphate stabilizes the carbonate group of polycarbonate from alcoholysis between the alcohol products of polycarbonate degradation and the carbonate linkage. Thus, the evolution of bisphenol A, which is mainly produced via hydrolysis/alcoholysis of the carbonate linkage, is significantly reduced, while, the evolution of various alkylphenols and diarylcarbonates increases. The bonds that are broken first in the thermal degradation of both the carbonate and isopropylidene linkages of polycarbonate are the weakest bonds in each, when a phosphate is present. Triphenylphosphate and resocinolbis(diphenyl-phosphate), even though they exhibit a significant difference in their volatilization temperature, appear to play a similar role in the degradation pathway of polycarbonate