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The increasing wildfire activity and rapid population growth in the wildland–urban interface (WUI) have made more Americans exposed to wildfire risk. WUI mapping plays a significant role in wildfire management. This study used the Microsoft building footprint (MBF) and the Montana address/structure framework datasets to map the WUI in Montana. A systematic comparison of the following three types of WUI was performed: the WUI maps derived from the Montana address/structure framework dataset (WUI-P), the WUI maps derived from the MBF dataset (WUI-S), and the Radeloff WUI map derived from census data (WUI-Z). The results show that WUI-S and WUI-P are greater than WUI-Z in the WUI area. Moreover, WUI-S has more WUI area than WUI-P due to the inclusion of all structures rather than just address points. Spatial analysis revealed clusters of high percentage WUI area in western Montana and low percentage WUI area in eastern Montana, which is likely related to a combination of factors including topography and population density. A web GIS application was also developed to facilitate the dissemination of the resulting WUI maps and allow visual comparison between the three WUI types. This study demonstrated that the MBF can be a useful resource for mapping the WUI and could be used in place of a national address point dataset. 

The gas exchange between water bodies and air is difficult to measure, thus the approximations of air–water gas exchange coefficient based solely on wind speed has been widely used. However, such approaches may not work well in river environments. In rivers, water currents may govern gas exchange. Thus, a new approximation for calculating the gas exchange coefficient (k) based on the near‐surface velocity scale (u_s) is suggested and compared to wind‐based estimates. Our velocity scale estimates are based on field observations during summer 2016 on the Yenisei River using an Acoustic Doppler Current Profiler, high‐frequency temperature profilers and a vessel‐mounted meteorological sensors‐suite. The results demonstrate thatu_s‐derived gas exchange coefficients are higher than those based solely on wind speed. The results demonstrate that the wind approximation underestimates gas exchange coefficients during low‐wind conditions.

 

Bode integrals of sensitivity and sensitivity-like functions along with complementary sensitivity and complementary sensitivity-like functions are conventionally used for describing performance limitations of a feedback control system. In this paper, we show that in the case when the disturbance is a wide sense stationary process the (complementary) sensitivity Bode integral and the (complementary) sensitivity-like Bode integral are identical. A lower bound of the continuous-time complementary sensitivity-like Bode integral is also derived and examined with the linearized flight-path angle tracking control problem of an F-16 aircraft.