For simple random walk on a finite tree, the cover time is the time taken to visit every vertex. For the balanced b-ary tree of height m, the cover time is shown to be asymptotic to 2mb(log b)/(b− 1) as m→∞. On the uniform random labeled tree on n vertices, we give a convincing heuristic argument that the mean time to cover and return to the root is asymptotic to 6(2π)n, and prove a weak O(n) u...

Passband balanced-steady-state free precession (b-SSFP) fMRI is a recently developed method that utilizes the passband (flat portion) of the b-SSFP off-resonance response to measure MR signal changes elicited by changes in tissue oxygenation following increases in neuronal activity. Rapid refocusing and short readout durations of b-SSFP, combined with the relatively large flat portion of the b-...

Glottal stops that occur in vowel-consonant-vowel context are often not realized as stops at all, but rather show voicing that is continuous throughout the glottal constriction gesture. Glottal articulations that are realized in this way are apparently marked by reductions in amplitude and fundamental frequency. In the present study measurements from naturally produced utterances containing the...

A squashed full flat antichain (SFFA) in the Boolean lattice Bn is a family A∪B of subsets of [n] = {1, 2, . . . , n} such that, for some k ∈ [n] and 0 ≤ m ≤ ( n k ) , A is the family of the first m k-sets in squashed (reverse-lexicographic) order and B contains exactly those (k−1)-subsets of [n] that are not contained in some A ∈ A. If, in addition, every k-subset of [n] which is not in A cont...

Coral reefs are built of calcium carbonate (CaCO3) produced biogenically by a diversity of calcifying plants, animals, and microbes. As the ocean warms and acidifies, there is mounting concern that declining calcification rates could shift coral reef CaCO3 budgets from net accretion to net dissolution. We quantified net ecosystem calcification (NEC) and production (NEP) on Dongsha Atoll, northe...

The optimal path cover problem is to find a minimum number of vertex disjoint paths which together cover all the vertices of the graph. Finding an optimal path cover for an arbitrary graph is known to be NP-complete [3]. However, polynornial-time algorithms exist for trees [4], cacti [4] and for interval graphs [9]. The solution presented in [2] For circular-arc graphs is known to be wrong. In ...

Evaluating and improving snow models and outflow predictions for hydrological applications is hindered by the lack of continuous data on bulk volumetric liquid water content (θw) and storage capacity of the melting snowpack. The combination of upward looking ground-penetrating radar and conventional snow height sensors enable continuous, nondestructive determinations of θw in natural snow cover...

This study, in a broad sense, fills in the missing parts in previous efforts at pullback stripping mode design with a dipping coal seam. Three different spoiling procedures have been developed: the normal mode, where the coal seam is flat/nearly flat; the uphill mode, where the coal seam is dipping and the dragline spoils uphill; and the downhill mode, where the coal seam is again dipping but t...