Background: Separate radon and thoron measurements in soil are very important in assessment of internal exposure due to inhalation of such radioactive gases. Materials and Methods: In this study, a low cost, small size, passive diffusion chamber has been developed for simple measurement of Radon-222 and Radon-220(Thoron) gases separately in soil. The diffusion chamber consists of two films and ...

rameterized for a given porous medium by slope and intercept values obtained through field calibration (HigThe neutron thermalization method for soil water content measurenett and Evett, 2002). For probe designs common in the ment is well established as being accurate for deep soil profile measurements. However, the method has been criticized as inaccurate for 1960s, about 95% of the measured s...

There is growing global interest in the potential for soil reflectance spectroscopy to fill an urgent need more data on properties improved decision-making security at local scales. This driven by capability of estimate a wide range from rapid, inexpensive, and highly reproducible measurement using only light. However, several obstacles are preventing wider adoption spectroscopy. The biggest la...

This study presents a robust evolutionary computational technique, called multi-expression programming (MEP), to derive a highly nonlinear model for the prediction of compression index of fine-grained soils. The proposed model relates the soil compression index to its liquid limit, plastic limit and void ratio. The experimental database used for developing the models was established upon 108 co...

This paper presents an integrated assessment model aimed at evaluating land degradation by water erosion in dehesa rangelands in the Iberian Peninsula. The model is built following the system dynamics approach. The degradation risk is likened to the probability of losing a certain amount of soil within a number of years, as estimated over a great number of stochastic simulations. Complementary ...

Microwave remote sensing has shown proof of its effectiveness for frozen ground mapping due to the high difference of permittivity between frozen and unfrozen soil. However, the characterization of seasonal frozen ground still remains a problematic application. The Japan Aerospace Exploration Agency (JAXA) launched the Advanced Land Observing Satellite (ALOS) on the 24 of January 2006. This sat...

Using the probably approximately correct (PAC) learning hypothesis, we have conducted experiments using clustered computers, high-performance workstations and ad-hoc grids of personal computers, to develop an analytical model for, and demonstrate asymptotic convergence of simple parallel search in the parameter space of complex environmental models such as the Soil and Water Assessment Tool (SW...