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Rainfall is one of the factors affecting soil erosion, and rainfall kinetic energy or momentum is used to represent the capability of the precipitation to erode soil, named rainfall erosivity. Accurate measurements of rainfall erosivity are useful for a reliable prediction of soil loss. Rainfall momentum and kinetic energy, both calculated per unit time and area, can be obtained using terminal raindrop velocity and the drop size distribution (DSD) measured by disdrometers, which are instruments expensive and not suitable for large scale use. An innovative patented method to measure the rainfall energy is based on the estimation of DSD by simultaneous detection, in a given time interval, of the rainfall intensity I and the number N of raindrops that hit a specific piezoelectric surface. In this paper, advances of this method are presented. In particular, two new theoretical procedures to estimate the parameters μ and Λ of Ulbrich's distribution, that allow for the calculation of the rainfall kinetic energy and momentum, are proposed. Both procedures (Scenario 1 and 2) are based on the frequency distribution of the momentum M(D) of raindrops detected in a sampling time interval. Specifically, in the Scenario 1, μ and Λ are estimated by using I, N and the standard deviation, s(D), of the drop diameters obtained from the measured momentum distribution. In the Scenario 2 the parameters are estimated using I, N and the mean value, m(D), of the drop diameters deriving from the momentum distribution. The reliability of the proposed procedures was tested using DSD measurements recorded in three different experimental sites. The developed analysis demonstrated that Scenario 2 is the best method to estimate μ and Λ, and to reproduce the DSD, accordingly. The proposed method, associated with a patented device, not yet build, will allow the direct measurement of the rainfall energy characteristics, which are usually roughly estimated from rainfall intensity. The possibility to easily measure these energy variables can support the development of research in the field of soil erosion and, in general, of hydrogeological instability. In particular, the proposed measurement method and the construction of the device could stimulate the scientific community to deepen the study of the effect of the rainfall energy on soil erosion for improving the predictive capability of water erosion models. [ABSTRACT FROM AUTHOR]

Este artículo identifica, caracteriza y describe las etapas del proceso productivo, logístico y regulatorio de medicamentos y las relaciones entre las mismas desde un enfoque de valor. Para la caracterización se adaptan el concepto de cadena de valor y la metodología de análisis de funciones básicas para los procesos de medicamentos innovadores. El concepto de valor mostró ser un paradigma de caracterización importante para este proceso particular. El trabajo descriptivo pretende servir de base para futuras investigaciones aplicadas a la cadena industrial de medicamentos y el sector académico.The stages of the manufacture, logistics and regulatory process of medicines are identified and described in this paper and their relations are analysed from a value approach. Concepts on value chain and development of a functional basis for design are adapted in order to characterize the processes for innovation of medicines. The value concept showed to be an important paradigm for characterization of this particular process. This descriptive work may be used as base of future studies in both the pharmaceutical industry sector and the academic sector.

In this paper, experimental data collected in a straight flume having a bed covered by grasslike vegetation have been used to analyze flow resistance for flexible submerged elements, At first, the measurements are used to test the applicability of Kouwen's method. Then, a calibration of two coefficients appearing in the semilogarithmic flow resistance equation is carried out. Finally, applying the II-theorem and the incomplete self-similarity condition, a flow resistance equation linking the friction factor with the shear Reynolds number, the depth-vegetation height ratio and the inflection degree is deduced. GE Database subject headings: Open channel flow: Flow resistance: Vegetation: Dimensional analysis.

Soil erosion research has established that sources of sediment are not necessarily areas involved in intense soil erosion because of the capacity of different parts of a basin to transport [...]

The stages of the manufacture, logistics and regulatory process of medicines are identified and described in this paper and their relations are analysed from a value approach. Concepts on value chain and development of a functional basis for design are adapted in order to characterize the processes for innovation of medicines. The value concept showed to be an important paradigm for characterization of this particular process. This descriptive work may be used as base of future studies in both the pharmaceutical industry sector and the academic sector.

Understanding of the hydraulics of flow over vegetation is very important to support the management of fluvial processes. In this paper the flow over flexible bottom vegetation is experimentally studied. A two-dimensional-acoustic doppler velocimeter is used to measure the local flow velocities for different vegetation concentrations, discharges, and flume slopes. The influence of vegetation concentration and the depth/vegetation height ratio on the measured velocity profiles is analyzed. All measured velocity distributions are S-shaped and exhibit a three-zone profile. The relationship between the velocity distribution and the turbulence intensity distribution is also analyzed. The characteristics (inflection point, maximum value, asymptotes) of the measured velocity distributions and the results of the previous investigators are used to select an analytical expression for the shape of the velocity profile. A theoretical velocity profile is deduced using the classical Prandtl's mixing length approach with a new expression for the mixing length. The deduced four-coefficient profile allows description of the flow both inside and above the vegetation. The physical and geometrical meaning of the four coefficients are also shown. DOI: 10.1061/(ASCE)0733-9429(2002)128:7(664) CE Database keywords: Velocity profile; Vegetation; Channel flow.