Penetration Depth of a Soil Moisture Profile Probe Working in Time-Domain Transmission Mode

Soil moisture is one of the most important soil parameters. Knowledge of volumetric water content (VWC) of the root zone as well as the VWC dynamics in the soil profile is especially important for agriculture. Monitoring VWC at several depths in the soil profile can be performed using several soil moisture sensors placed at various depths. However, the use of a profile probe is more convenient, because the installation of a single probe is less disturbing to the soil, as well as less laborious and more cost-effective. The objective of the paper is to present the design and performance of a novel profile probe working in the time-domain transmission mode (P-TDT probe) with emphasis put on the penetration depth and sensitivity zone. The performance of the probe was assessed with the use of finite element method (FEM) simulations in the frequency domain, transient simulations in the time domain and laboratory experiments with the use of a vector network analyzer (VNA) working in the 10 MHz–10 GHz frequency range. It was concluded that the effective soil volume measured by the profile probe of a given geometry is equivalent to a soil thickness of about 20 mm around the tested probe. The internal part of the probe body had a negligible effect on the measurement results, as it does not change with soil moisture. Moreover, the transmitted signal amplitude was related to the soil electrical conductivity

A FDR Sensor for Measuring Complex Soil Dielectric Permittivity in the 10–500 MHz Frequency Range

Mechanical details as well as electrical models of FDR (frequency domain reflectometry) sensors for the measurement of the complex dielectric permittivity of porous materials are presented. The sensors are formed from two stainless steel parallel waveguides of various lengths. Using the data from VNA (vector network analyzer) with the connected FDR sensor and selected models of the applied sensor it was possible obtain the frequency spectrum of dielectric permittivity from 10 to 500 MHz of reference liquids and soil samples of various moisture and salinity. The performance of the analyzed sensors were compared with TDR (time domain reflectometry) ones of similar mechanical construction

Data on the quality of life after cytoreductive surgery and hyperthermic intraperitoneal chemotherapy for peritoneal malignancies: does it concern patients with gastric cancer?

AbstractIntroduction.So far there are no reports devoted exclusively to the quality of life after cytoreductive surgery and hyperthermic intraperitoneal chemotherapy in metastatic gastric cancer. Current literature concerning this issue was, thus, reviewed in order to: 1) search for such data concerning metastatic gastric cancer; 2) assess if the latest reviews evenly pertain to all peritoneal surface malignancies; and 3) conclude if they are a reliable source of data for patients with metastatic gastric cancer.Materials and Methods.The electronic PubMed/MEDLINE and EMBASE databases were retrieved for studies concerning the influence of cytoreductive surgery and hyperthermic intraperitoneal chemotherapy on quality of life in patients with metastatic gastric cancer and regardless of initial diagnosis. The data on the number of patients with particular tumours were analysed and the results were presented in the form of a table.Results.Approximately half of all patients encompassed by the reviews had a form of primary peritoneal surface malignancies. Within peritoneal metastases, the most numerous were colorectal (21-24%) and ovarian cancers (5-15%). Gastric cancers and sarcomas were the smallest defined subgroups (4% each).Conclusions.The promising outcomes in quality of life after cytoreductive surgery and hyperthermic intraperitoneal chemotherapy in primary peritoneal surface malignancies might differ from rarely reported ones in metastatic gastric cancer. The problem needs further, gastric cancer-devoted investigations

Soft-computing techniques in soil hydrological parameters modelling

1 copia .pdf (15 Pags., with Figs. y Tabls.) de la presentación orginal de los autores en el Congreso Internacional.The idea of the soft-computing Soft-computing models: * based on the data learning, * does not provide analytical solution of the problem,solutions are by by de nition inexact and approximate, * allow for modelling of the properties or behaviour of the complex systems without deep insight, * gives speci c solution for currently modelled phenomenon. Classical models: * based on full physical-mathematical modelling, * described by some class of exact mathematical equations, * often expensive in the sense resources utilised for solving the problem (computing time), * universal for the given phenomenon described.Peer reviewe

TDR Technique for Estimating the Intensity of Evapotranspiration of Turfgrasses

The paper presents a method for precise estimation of evapotranspiration of selected turfgrass species. The evapotranspiration functions, whose domains are only two relatively easy to measure parameters, were developed separately for each of the grass species. Those parameters are the temperature and the volumetric moisture of soil at the depth of 2.5 cm. Evapotranspiration has the character of a modified logistic function with empirical parameters. It assumes the form ETRθ2.5 cm,T2.5 cm=A/1+B·e-C·θ2.5 cm·T2.5 cm, where: ETRθ2.5 cm,T2.5 cm is evapotranspiration [mm·h−1], θ2.5 cm is volumetric moisture of soil at the depth of 2.5 cm [m3·m−3], T2.5 cm is soil temperature at the depth of 2.5 cm [°C], and A, B, and C are empirical coefficients calculated individually for each of the grass species [mm·h1], and [—], [(m3·m−3·°C)−1]. The values of evapotranspiration calculated on the basis of the presented function can be used as input data for the design of systems for the automatic control of irrigation systems ensuring optimum moisture conditions in the active layer of lawn swards

Using SVM for soil water retention modelling

1 copia .pdf (a-3) del póster original presentado (2 Figs., 2 Tabls.)This work presents point pedotransfer function models of the soil water retention curve. Developed models allow for estimation of the soil water content based on following soil characteristics: soil granulometric composition, total porosity and bulk density. Soil water content is evaluated for the specified soil water potentials: -0.98 kPa, -3.10 kPa, -9.81 kPa, - 31.02 kPa, -491.66 kPa and -1554.78 kPa. Support Vector Machines (SVM) methodology was used for model development. Alternative to previous attempts ν-SVM method was used for models development and results compared with C-SVM based models. In the work two different types of the SVM kernel function was used and results compared: radial basis kernel function with the linear one. Soil properties used as input variables for the PTF models are: sand fraction, clay fraction, total porosity and bulk density. Models approximate value of the soil water content for seven fixed values of the soil water potential.Peer reviewe