Rate effects are examined in the steady pore pressure distribution induced as a result of penetration of standard and ball penetrometers. The incompressible flow field, which develops around the penetrometer is used to define the approximate soil velocity field local to the penetrometer tip. This prescribes the Lagrangian framework for the migration of the fluid saturated porous medium, definin...

A cone penetrometer is widely used in tillage and off-road mobility research as an indicator of soil strength and density characteristics. Light-weight, manually operated units are especially useful in recording cone index determination at remote field locations. An electronically hand-pushed soil penetrometer with a microcontroller-based data logging system was designed and fabricated to provi...

Abstract. Cone penetration tests have long been used to characterize snowpack stratigraphy. With the development of sophisticated digital penetrometers such as SnowMicroPen, vertical profiles snow hardness can now be measured at a spatial resolution few micrometers. By using small penetrometer tips this high resolution, further details process are resolved, leading many more stochastic signals....

Abstract Replacement of bare fallow in rotations by cover crops is a promising tool to reduce crusting, although the interactions with soil moisture and effect crop species are still not well understood. The objective this work was determine how modify surface response penetration their relation water content. Two winter crops, barley (Hordeum vulgare L.) vetch (Vicia sp. L.), were compared tre...

We developed the Temperature 2 Pressure probe (T2P) to measure in-situ pore pressure and temperature in sediments at the base of the borehole. Tool development began in 2003, it was land-tested in 2004, and it was deployed on the IODP’s Joides Resolution drillship in June 2005 on IODP Expedition 308. During Expedition 308, we measured temperature and pressure in mudstones up to 300 meters below...

Inventories of the necromass of coarse woody debris typically involve measurements of density (e.g., kilograms per cubic metre) on a sample of logs, with densities of other logs estimated based on assignment to decay classes. Here, we compare two new devices for assessing density of woody debris, a spring penetrometer and a dynamic penetrometer, with the traditional decay classification and kni...

A solution is developed for the buildup, steady, and postarrest dissipative pore fluid pressure fields that develop around a conical penetrometer that self-embeds from free-fall into the seabed. Arrest from free-fall considers deceleration under undrained conditions in a purely cohesive soil, with constant shear strength with depth. The resulting decelerating velocity field is controlled by soi...

Background: During the coronavirus disease 2019 (COVID-19) pandemic face masks grew in importance as their use by general population was recommended health officials order to minimize risk of infection and prevent further spread virus. To ensure protection medical personal other system relevant staff, it is considerable interest quickly test if a certain lot filterin...

Advance in GNC, particularly from miniaturized control electronics, reaction-wheels and attitude determination sensors make it possible to design surface probes and small robots to perform surface exploration and science on lowgravity environments. These robots would use their reaction wheels to roll, hop and tumble over rugged surfaces. These robots could provide “Google Streetview” quality im...