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Abstract We present cosmological analysis of 12 nearby (z< 0.06) Type IIP supernovae (SNe IIP) observed with the ROTSE-IIIb telescope. To achieve precise photometry, we present a new image-differencing technique that is implemented for the first time on the ROTSE SN photometry pipeline. With this method, we find up to a 20% increase in the detection efficiency and significant reduction in residual rms scatter of the SN lightcurves when compared to the previous pipeline performance. We use the published optical spectra and broadband photometry of well-studied SNe IIP to establish temporal models for ejecta velocity and photospheric temperature evolution for our SNe IIP population. This study yields measurements that are competitive with other methods even when the data are limited to a single epoch during the photospheric phase of SNe IIP. Using the fully reduced ROTSE photometry and optical spectra, we apply these models to the respective photometric epochs for each SN in the ROTSE IIP sample. This facilitates the use of the Expanding Photosphere Method (EPM) to obtain distance estimates to their respective host galaxies. We then perform cosmological parameter fitting using these EPM distances, from which we measure the Hubble constant to be ${72.9}_{-4.3}^{+5.7}\mathrm{km}{\mathrm{s}}^{-1}{\mathrm{Mpc}}^{-1}$, which is consistent with the standard ΛCDM model values derived using other independent techniques. 

The need for scientific ice drilling in glaciers and ice sheets has been driven by many fields of science, including drilling ice cores for evidence of past environment and paleoclimate information, and drilling access holes through the ice to gather data relevant to glacial dynamics, history of glacier extent, sediment sampling, and discovery of ecosystems within and beneath the ice. Many nations have contributed to drilling technologies relevant to each of these fields, and developments in any one nation often build on prior designs from other nations. A description of the very early polar ice coring endeavors in Greenland and Antarctica is provided in Langway (2008). Ice drilling and coring technologies that were developed before 2008 are well described in Bentley et al (2009), including a wide array of ice coring drills, drills designed to create holes in ice only, and autonomous instruments that melt their way through ice. The text by [Talalay 2016] provides a review of mechanical ice drilling technology that includes design, parameters and performance of an assortment of tools and drills for making holes in snow, firn and ice. Described in detail are direct-push drilling, hand- and power-driven portable drills, percussion drills, conventional machine-driven rotary drill rigs, flexible drill-stem drill rigs, cable-suspended electromechanical auger drills, cable-suspended electromechanical drills with bottom-hole circulation, and drilling challenges and perspective for future development. In this chapter our goal is to describe new ice drilling and coring technologies that have been designed, built, and used in the field in the most recent decade. Some of these technologies are improvements on prior drills, while other technologies such as a replicate ice coring drill, geologic drilling underneath many meters of glacial ice, and the rapid access isotope drill are the first of their kind. There are many additional ice drilling and sampling designs currently in the design or development stage that are not included in this chapter; rather our goal in this chapter is to describe proven ice drilling technologies that have been developed since 2009.