In recent years, such small body exploration missions as asteroids or comets have received remarkable attention in the world. In small body explorations, especially, detailed in-situ surface exploration by tiny rover is one of effective and fruitful means and is expected to make strong contributions towards scientific studies. JAXA/ISAS is promoting MUSES-C mission, which is the world’s first s...

We study the use of randomized value functions to guide deep exploration in reinforcement learning. This offers an elegant means for synthesizing statistically and computationally efficient exploration with common practical approaches to value function learning. We present several reinforcement learning algorithms that leverage randomized value functions and demonstrate their efficacy through c...

The surface regions of cometary nuclei are expected to be extensively modified by cosmic radiation and solar insolation. Induced state changes and associated sublimation and phase-change boundaries are expected to propagate deep into the interior. In the current exploration program a reconnaissance of the highly evolved upper meter of the cometary surface is comprehensively covered. However, th...

This technical note presents a new approach to carrying out the kind of exploration achieved by Thompson sampling, but without explicitly maintaining or sampling from posterior distributions. The approach is based on a bootstrap technique that uses a combination of observed and artificially generated data. The latter serves to induce a prior distribution which, as we will demonstrate, is critic...

magnetotellurics (mt) is an electromagnetic geophysical method of imaging the earth's subsurface by measuring natural variations of the electrical and magnetic fields at the earth's surface. investigation depth ranges from 300m below ground by recording higher frequencies down to 10,000m or deeper with long-period soundings. research applications include experimentation to further dev...

[1] We analyzed aftershocks and postseismic deformation recorded by the continuous GPS station AREQ following the Mw = 8.4, 23 June 2001 Peru earthquake. This station moved by 50 cm trenchward, in a N235 E direction during the coseismic phase, and continued to move in the same direction for an additional 15 cm over the next 2 years. We compare observations with the prediction of a simple one-di...

[1] Two of the most popular mechanisms for thickening the crust beneath the Tibetan Plateau are (1) pure shear with faulting and folding in the upper crust and horizontal shortening below and (2) flow of lower or middle crust without significant shortening of the upper crust. To help discriminate between the relative contributions of these two mechanisms, well-constrained estimates of upper cru...

One of the fundamental geophysical observations made of the Earth is the stratified nature of the continental crust, in which the lower crust comprises denser, more mafic material and the upper crust comprises less dense, more felsic material. This chemically differentiated layered structure is developed and maintained by partial melting at depth and the ascent of magma to shallower crustal lev...

Abstract Crustal fault zones provide interesting geological targets for high-temperature geothermal energy source in naturally deep-fractured basement areas. Field and laboratory studies have shown the ability of these systems to let fluid flow down brittle–ductile transition. However, several key questions about exploration still exist, particular fundamental effect tectonic regimes on fractur...