The influence of the combined effect of draught and radiant thermal asymmetry on human performance

Currently, there are studies which show the separate effect of the local discomfort parameters such as the draught and radiant thermal asymmetry. However, no studies have been conducted to find out the combined effect of the before mentioned two discomfort parameters on human performance. In order to fill this gap, a 17 months experiment was performed at the Budapest University of Technology and Economics. Throughout the experiment twenty human subjects (ten women and ten men) performed different cognitive tests and responded to questionnaires. Two different draught rates and five different radiant thermal asymmetry values were imposed in the Macskásy climate chamber, where the experiment took place. The results show the consequence of the combined effect of draught and radiant thermal asymmetry on the human performance.

Axial dispersion and mixing of coolant gas within a separate-effect prismatic modular reactor

Multiphase Reactors Engineering and Applications Laboratory performed gas phase dispersion experiments in a separate-effect cold-flow experimental setup for coolant flow within heated channels of the prismatic modular reactor under accident scenario using gaseous tracer technique. The separate-effect experimental setup was designed on light of local velocity measurements obtained by using hot wire anemometry. The measurements consist of pulse-response of gas tracer that is flowing through the mimicked riser channel using air as a carrier. The dispersion of the gas phase within the separate-effect riser channel was described using one-dimensional axial dispersion model. The axial dispersion coefficient and Peclet number of the coolant gas phase and their residence time distribution within were measured. Effect of heating intensities in terms of heat fluxes on the coolant gas dispersion along riser channels were mimicked in the current study by a certain range of volumetric air flow rate ranging from 0.0015 to 0.0034 m3/s which corresponding to heating intensity range from 200 to 1400 W/m2. Results confirm a reduction in the response curve spreads is achieved by increasing the volumetric air velocity (representing heating intensity). Also, the results reveal a reduction in values of axial dispersion coefficient with increasing the air volumetric flow rate.

Decomposing diversification effect: evidence from the U.S. property-liability insurance industry

Prior literature suggests that diversified property-liability (P/L) insurers underperform their focused counterparts. While most studies focus on insurers’ overall performance, there is an absence of evidence regarding whether the underperformance is driven by underwriting or investment profitability. The authors develop and test hypotheses of diversification’s separate effect on underwriting and investing in the U.S. property-liability (P/L) insurance industry. It is found that diversified insurers outperform their focused counterparts in terms of investment return, but that they underperform in terms of underwriting profitability. The results are robust to corrections for endogeneity bias and a matched sample analysis.