Characteristics of Trees Infested by the Invasive Primary Wood-Borer Aromia bungii (Coleoptera: Cerambycidae).

The expanding distribution and tree damage of the invasive, primary wood-borer Aromia bungii (Coleoptera: Cerambycidae), which kills trees of the Rosaceae family, is a problem in intruded areas. However, the tree characteristics associated with infestation by A. bungii, which are useful for early detection or prioritizing preventive measures, are not well examined. We investigated the presence or absence of tree damage (response variable) in pre- and post- surveys along with tree characteristics (four explanatory variables; bark roughness, size, species, and vigor) on monitoring trees in uninvaded sites (survey for the first trees to be damaged) and already invaded sites (survey for the next trees to be damaged). We evaluated the variables using generalized linear mixed models for each site (i.e., a first trees model and a next trees model). Three tree characteristics (bark roughness, size, and vigor) were included as explanatory variables in both best models, indicating that trees with rough surface bark, large in size, and weakened conditions were more susceptible to A. bungii infestation. The reasons for the difference between the two models (species was only chosen in the next trees model) will be considered in our future work.

Structure of high-performance evaporators for space application.

A new structure of cold plates, where an unheated auxiliary channel is installed to supply liquid directly to the bottom of coalesced flattened bubbles in a narrow heated channel, is tested to investigate the increase in critical heat flux. Assuming the application to the laser solar power system, a large heating surface with a length of 150 mm in the flow direction is employed, and a narrow channel structure is adopted to reduce the size of cold plates, where the gap sizes are selected as 5 mm and 2 mm. Experiments are performed for water as a test liquid at inlet subcooling of 15 K under near atmospheric pressure. Inlet liquid velocity is varied from 0.065 m/s to 0.6m/s for the upward flow on ground. A value of critical heat flux of 2.2 x 10(6) W/m2 is obtained for 5-mm gap size at the inlet velocity of 0.2 m/s. At low liquid flow rate, the structure realizes the CHF values larger by 2.5 times than those for the normal heated channel without additional liquid supply. A new method to evaluate the performance of cold plates is proposed to take account of the variation in the size of heating surface, inlet liquid velocity, and subcooling that influence the CHF values. The validity of the proposed structure of the cold plate for the increase in critical heat flux is confirmed.